JPH033559A - Position adjustment mechanism for picture reader - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides photoelectric conversion of an original image by relatively moving an original image projected by an imaging lens and a photoelectric conversion element for reading the original image in the sub-scanning direction. The present invention relates to a position adjustment mechanism for an image reading device that reads images.

[Prior Art] In recent years, optical reading devices for document images have been widely used in office equipment such as copying machines and facsimile machines. The size of documents to be read in general is limited to a maximum of A3 size,
In certain fields such as industrial drawings, the target manuscript size is 8411a (JISAO size) to 3.
61/(941mo+) (ANSI E size)
There are some that have been made larger. For such large documents, one photoelectric conversion element (hereinafter referred to as CCD) is required.
That's what it means. ), it is impossible to reduce and project an image and read it, and conventional reading devices for general office use cannot read with sufficient image density.

Therefore, an apparatus has been proposed in which a large document image is dividedly projected onto a plurality of CCDs using a plurality of imaging lenses, and the image is read in correspondence with each projected image.

[Problem to be solved by the invention] However, in such a split-type reader, for example, vX
Not only do the main scanning directions of each CCD perfectly match in both image width directions, but also the positioning and arrangement is performed so that each COD is perpendicular to the optical axis in the sub-scanning direction.
Unless the original image and the photoelectric conversion element are moved relative to each other, it is impossible to photoelectrically read the original image.

In particular, for high-density CCD linear sensors used when high-density reading is required, highly accurate position adjustment must be performed in relation to the projection magnification or reading overlap amount for each COD, as well as temperature changes. .

On the other hand, the lens barrels that make up the imaging lens are also processed and assembled with high precision.
When moving the imaging lens in the optical axis direction, it must be adjusted so that the optical axis will not be tilted or decentered, and consideration must be given to avoid positional deviation when fixing after movement.

Conventionally, in Japanese Patent Application Laid-Open No. 51-51217, etc.,
Although various supporting structures for the CCD and the imaging lens have been proposed, all of them suffer from positional deviation when aligning the focusing lens or fixing the imaging lens after positioning. It is no longer possible to make them perform well.

The present invention enables accurate and easy adjustment of the main scanning direction, sub-scanning direction, and lens optical axis direction of the imaging lens by eliminating positional deviation when positioning the imaging lens. An object of the present invention is to provide a position adjustment mechanism for an image reading device that allows for the adjustment of the position of an image reading device.

[Means for Solving the Problems] In order to achieve the above object, the invention described in claim 1 projects a document image onto a photoelectric conversion element using an imaging lens, and combines the document image and the photoelectric conversion element. In the position adjustment mechanism of the image reading device, the lens barrel support holder accommodates the lens barrel of the imaging lens, and the lens barrel support holder accommodates the lens barrel of the imaging lens, and An adjustment shaft held in the lens barrel support holder so as to be movable in an axial direction perpendicular to the axis of the lens barrel and rotatable around the axis, and a connection based on rotational movement of the adjustment shaft around the axis. It has each component of an eccentric cam mechanism that moves the lens barrel of the image lens in the optical axis direction, and a pressing means that presses the adjustment shaft in the axial direction toward the imaging lens side and in the direction orthogonal to the axis. A focus adjustment device is provided.

Further, the invention described in claim 2 projects a document image onto a photoelectric conversion element using an imaging lens, and
In the position adjustment mechanism of an image reading device that photoelectrically reads the original image by relatively moving the original image and the photoelectric conversion element in the sub-scanning direction, a lens barrel support holder that accommodates the lens barrel of the imaging lens is provided. an adjustment shaft held by the lens barrel support holder so as to be movable in an axial direction perpendicular to the axis of the lens barrel of the imaging lens and rotatable around the axis; and an axis of the adjustment shaft. an eccentric cam mechanism that moves the lens barrel of the imaging lens in the optical axis direction based on rotational movement; and a pressing means that presses the adjustment shaft in the axial direction toward the imaging lens and in the direction orthogonal to the axis. , a rotation locking means for pressing the barrel of the imaging lens in the direction of the optical axis and regulating the barrel of the imaging lens in the direction around the optical axis; It is being

Furthermore, the invention set forth in claim 3 provides a position C adjustment mechanism for an image reading device set forth in claims 1 and 2, in the axial direction toward the imaging lens side and in the direction orthogonal to the axis. The pressing means for pressing the adjustment shaft is provided with means for decomposing the pressing force in one direction into component forces in the axial direction toward the imaging lens and in the direction orthogonal to the axis.

[Function] In a means having such a configuration, the lens barrel of the imaging lens is moved and adjusted in the optical axis direction via the eccentric cam mechanism by the rotational movement of the adjustment shaft around the axis, and the pressing means or rotation The locking means maintains the adjustment shaft and the imaging lens in a constant position.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

As shown in FIG. 1, the original 12 is illuminated by a long illumination lamp 11, so that the image on the original 12 is formed in the exposure line 13 by the three imaging lenses 4'.
, 5.6, one-dimensional photoelectric conversion element (hereinafter CC
(abbreviated as D)) is projected onto a pixel column of 1.2°3.

Each light beam 7°8.9 in the imaging lenses 4, 5.6 is directed to a predetermined area 12.2-Q□ in the exposure line 13.
, are overlapped, and the CCDI, 2, 3
When the read signal is output to a writing device (not shown), control is performed to prevent omissions, duplications, shifts, etc. from occurring at predetermined positions in each overlap area.

The document 12 is conveyed by a conveying means (not shown) along an exposure line 13 on a transparent flat glass plate from its leading edge to its trailing edge in the direction of the arrow shown in the figure at a speed corresponding to a predetermined reading speed. This allows all images of the document to be read.

Further, as shown in FIG. 2, the area Q2 on the exposure line 13 of the original 12 is
The image is reduced by 102 times and imaged on the pixel row of the CCD 2. CCD2 has 7μm x 7μm pixels 5
It consists of a linear sensor having 000 pixels (picxel), and the length of the pixel row is set to 35 +++ m. Therefore, the length of the area a2 is 317.5n
+n+. Here, the width of the original 12 on the exposure line 13, that is, the maximum reading @Q is 914.4nn.
Then, the amount of overlap on the exposure line 13 is 0□2
-Q23 is 6.35 mm, and pixel row 2 of CCD2
On a, it is 0.711111 (100 pixels).

In this way, the image of the original 12 is captured by a plurality of CCDs 1.

In order to read the image separately according to 2.3, each CGDI, the reading magnification and position of the read image in 2.3,
The range etc. needs to be positioned with a predetermined accuracy. Therefore, in this embodiment, as shown in FIG.
The position of 2 is movable for parallel fine adjustment in each direction: the X-axis direction which is the main scanning direction, the Y-axis direction which is the sub-scanning direction, and the Z-axis direction which is the optical axis direction of the imaging lens 5. , can be rotated and finely adjusted around each of the X-axis direction, Y-axis direction, and Z-axis direction.

As shown in FIGS. 3, 4, and 5, the reading unit 15 has an imaging lens 5 with respect to the base 200.
A base plate 100 having a U-shaped cross section is mounted for parallel fine adjustment movement in the optical axis direction (Z-axis direction), and the optical center of the imaging lens 5 is perpendicular to the optical axis with respect to this base plate 100. , and a rotary base plate 80 mounted for fine rotational adjustment around a conical shaft 94 having an axis in the sub-scanning direction; a shading correction plate 97 movably screwed to the
The optical center of the imaging lens 5 is screwed to approximately the center of the front side wall 80c of the rotating base plate 8o so as to be able to finely adjust the rotation around a conical shaft 94 having an axis perpendicular to the optical axis and in the sub-scanning direction. A support shaft 64 is hooked between the lens unit 300, which is attached to the rotating base plate 8o, and a right boss 81 and a left boss 82, which are screwed to the lower part of the right side Q 80a and the left side wall 80b of the rotating base plate 8o. and a CCD base plate unit 30 mounted on the support shaft 64 so as to be finely adjustable in rotation and finely adjustable in the axial direction.

The above CCDCD base plate unit 30 has a CCD unit 1-2.
0 is held, and a seal member 310 having light shielding properties, dustproof properties, and air permeability is installed between this CCD unit 20 and the lens unit 300.

Further, as shown in FIGS. 14, 15, and 16, the base 200 is connected to the exposure line 13 of the original image.
The left support frame 230 is provided as an immovable member.
It is rotatably supported on the right support frame 231 via a left main shaft 215 and a right main shaft 217. The rotation plane is set to a plane that includes the optical center of the imaging lens 5 and is orthogonal to the optical axis of the imaging lens 5, and the left main axis 215 and the right main axis 217 are in the main scanning direction of the CCD, that is, the exposure direction. It has an axis in a direction parallel to the line 13. Furthermore, two stop shafts 214 are provided on both sides of the upper left shaft 215 in the direction perpendicular to the axis, and when these stop shafts 214 are tightened or loosened by set screws 222 and 223, the base 200 is rotated. The movement can be fine-tuned.

The CCD 2 of the CCD unit 20 is fitted into a substantially rectangular positioning hole 21g provided in the metal plate 21, as shown in FIGS. 7 and 8. At the edge of the positioning hole 21g, three supporting pieces are formed so as to protrude inwardly, and a main scanning direction base: 1JI21 is formed at the tip of each of these supporting pieces.
The end faces of the ceramic case of the CCD 2 in the main scanning direction and the end face in the sub-scanning direction are held in contact with a and sub-scanning direction references 921b and 21c, respectively. Furthermore, the main scanning direction base edge 21a and the sub-scanning direction reference edges 21b and 21c are accurately positioned with respect to the two mounting holes 21e provided in the metal plate 21, so that the pixel column 2a of C0D2 is positioned with a predetermined accuracy. At this time, the cover glass 2b of the CCD 2 and the upper surface of the metal plate 21 are placed on the same plane. Furthermore, a two-component epoxy resin is injected and hardened into the gap between the ceramic case of the CCD 2 and the positioning hole 21g, so that the CCD 2 remains immovable.

Further, a CCD control board PCl3-122 including an amplification circuit for amplifying the image reading signal from the CCD 2 is held by being soldered to the 22 connection pins 2c of the CCD 2. There are two connectors 2 on the COD control board PCB-122.
3 are soldered to each other, and flat cables 24 each consisting of a plurality of lead wires are detachably attached. C
Mounting hole 22 provided on CD control board PCB-122
A thermistor 25 for detecting the temperature of the CCD 2 is attached to the a, and is held in contact with the ceramic case of the CCD 2 by adhesion with epoxy resin.

Furthermore, the CCD control board PCB-122 has a connector 23.
is soldered, and one end of a flat cable 24 is inserted into this connector 23. The other end of the flat cable 24 is connected to a CCD control board PC.
It is inserted and connected to a connector 401 soldered to the B-2400 (see FIGS. 3 and 5). The CCD control board PCB-2400 constitutes the sleep control circuit of the CCD 2, and is larger than the CCD control board PCB-122 and is equipped with more control electronic components, so it generates heat. It's also big. Therefore, it is desirable that the COD control board PCB-2400 is installed as far away from the CCD 2 as possible, and in this embodiment, the COD control board PCB-2400 is installed with respect to the right support leg 100d and the left support leg 100e extending downward from the base plate 100. Screw 40
By being locked by 4, the COD control board PCB-
The heat generated by 122 is prevented from affecting the CCD 2.

COD control boards PCB- spaced apart from each other in this way
122 and the COD control board PCB-2400 using the flat cable 24, it is possible that electrical noise will be picked up through the flat cable 24 and it will not be possible to output an accurate signal corresponding to the ffX draft image. However, in this example, as mentioned above, C
A CCD control board PCB-122 directly connected to the CD 2 is provided with a read signal amplification function, thereby minimizing the influence of electrical noise. As a result, the flat cable 24 can be lengthened to a certain extent, which alleviates the positional restrictions on the COD control board PCB-2400, and at the same time, even if the position of the CCD 2 is adjusted over a relatively large range, unreasonable force is not applied to the CCD 2. This makes it possible to eliminate poor connection between the flat cable 24 and the connectors 23, 401 without imposing any load.

9 and 10 show other mounting structures for C0D2. In other words, at the edge of the positioning hole 21g,
Main scanning direction reference @21a and sub-scanning direction reference 1i21
In addition to b and 21c, the optical axis direction! 1a21f are provided at three locations, and C is
The cover glass 2b of the CD 2 is brought into contact and positioned. A two-component epoxy resin is injected and hardened into the gap 21d between the ceramic case of the CCD 2 and the positioning hole 21g, so that the CCD 2 remains immovable. In this way, positioning of the CCD 2 in the optical axis direction with respect to the metal plate 21 can be facilitated.

Further, FIG. 11 shows another mounting structure for the COD control board PCB-122. That is, CCD control board P
A socket 26 is connected to the CB-122 via a connecting pin 26a, and a connecting pin 2c of the CCD 2 is inserted into the socket 26. In this way, the CCD 2 can be replaced by inserting the connecting pin 2c of the CCD 2 into the sockets 1 to 26, or the
Replacing the OD control board PC[l-122] can be done easily and inexpensively.

Next, the lens unit 300 will be explained with reference to FIGS. 13, 5, and 3. The lens holder 301 is formed from an aluminum casting with a cross-sectional shape, and the rear part 301b of the lens holder 301 has three protrusions 301.
a is formed, and an attachment hole 303 to the rotating base plate 80 is also formed. The protruding tip plane part of the convex part 301e and the holder lower surface part 301d are cut so as to have a perpendicular relationship, and furthermore, with these both surfaces 301e and 301d as a reference, a fitting part for housing the imaging lens 5 is formed. A hole 304 is formed through the optical axis direction. That is, the axis of the fitting hole 304 is positioned accurately in parallel with the right-angled bottom of the holder lower surface 301d of the lens holder 301 and the flat surface of the protruding end of the convex portion 301e. The imaging lens 5 is fitted into the fitting hole 304 so as to be slid back and forth in the direction of its optical axis.

Further, a fitting hole 302 is formed in the rear part 301b of the lens holder 301, into which the outer circumference of the cylindrical female thread 95 is fitted. The cylindrical female screw 95 is used to lock the conical shaft 94 to the front wall 80c of the rotating base plate 8o. At this time, the formation position of the fitting hole 302 is precisely set on the optical center of the imaging lens 5 in a direction perpendicular to the optical axis of the lens and perpendicular to the flat surface of the protruding end of the convex portion 301e. There is. On the other hand, the movable base plate 5o holding the CCD base plate unit 30 is rotatably and slidably supported on the support shaft 64, and the lens unit 300 can be rotated and adjusted around the fitting hole 302. , holder bottom part 3
After 01d is set parallel to the support shaft 64, it is secured to the rotating base plate 8o with three screws 3o9. As a result, the optical axis of the imaging lens 5 and the support axis 6
4, the required perpendicularity accuracy is guaranteed.

Further, the tip of the plate spring 325 screwed to the front part 301a of the lens holder 301 is connected to the imaging lens 5.
The imaging lens 5 is pressed against the upper edge of the lens 5, so that the imaging lens 5 is pressed downward in the optical axis direction.

A fitting hole 305 is formed in the front part 301a of the lens holder 301 in a direction perpendicular to the lens optical axis.
A focus adjustment shaft 306 is rotatably fitted into the fitting hole 305 for finely adjusting and moving the imaging lens 5 in the optical axis direction for focusing and locking. Further, a screw hole 301f is formed in the front part 301a of the lens holder 301 so as to be perpendicular to the axis of the fitting hole 305, and a pressure rod 307 loosely fitted into the screw hole 301f is screwed into the screw hole 301f. 308, the focus adjustment shaft 306 is pressed in a direction perpendicular to the axis, thereby locking the focus adjustment shaft 306 at a predetermined position as described later. The pressure rod 307 is made of a flexible hard resin.

On the other hand, a groove 322 of a predetermined depth is formed in an annular shape on the outer periphery of the lens barrel 321 of the imaging lens 5.
A cylindrical eccentric cam 306a is formed at the rear end of the focus adjustment shaft 306, and this eccentric cam 306a is engaged in the groove 322. The eccentric cam 306a is formed with a diameter of 8, and the main shaft 3 of the focus adjustment shaft 306
It is eccentric by 1.5 pixels with respect to the axis of 06C, and
The length in the axial direction is set longer than the depth of the groove 322. The main shaft 306c of the focus adjustment shaft 306 is formed into a cylindrical shape with a diameter of 12 discs, and a conical portion 306d with an apex angle of 90° is formed on the opposite side of the eccentric cam 306c, and this conical portion 306d serves as a small diameter shaft. It is integrally connected to the auxiliary shaft 306f via 306e. Auxiliary shaft 3C) 6f
is formed to have the same diameter as the main shaft 306c, and the auxiliary shaft 306
A slotted portion 306g into which a driver can be fitted is formed on the end face of f. A conical portion 307a formed at the tip of the pressure rod 307 described above is pressed into contact with the conical inclined side surface of the conical portion 306d. Components P1 and P2 of the pressing force of the pressure rod 307 at these pressure contact points are directed in the axial direction and the direction orthogonal to the axis of the focus adjustment shaft 306, respectively, and the axial component P is applied to the eccentric cam 306a. The distal end surface 306b is pressed against the groove bottom surface 322a of the groove 322, so that the lens barrel 321
is pressed against the wall surface of the fitting hole 304 and maintained without any play. In addition, the main axis 30Go of the focus adjustment shaft 306 and the auxiliary axis 3
0f3 is pressed against the wall surface of the fitting hole 305 and maintained without any play, and rotation of the focus adjustment shaft 306 is braked by frictional force. At this time, the groove bottom surface 322a formed by the end surface 306b of the eccentric cam 306a
The pressing force, that is, the frictional force between the lens barrel 321 and the fitting hole 304 is based on the pressing force from the set screw 308 against the pressing rod 307, but at least the imaging lens 5
When the projected image is focused on the CCD 2 by
The pressing force from the set screw 308 against the pressure rod 307 is adjusted to such an extent that it does not become larger than the pressing force from the leaf spring 325 against the pressure rod 307 .

To adjust the focus of the imaging lens 5, first, the focus adjustment shaft 306 is rotated by engaging the slotted portion 306g of the driver. As a result, the eccentric cam 306a is eccentrically rotated, and the imaging lens 5 is moved in the optical axis direction, so that the CCD 2
The focus of the projected image is adjusted. At this time, the imaging lens 5 is prevented from rotating around the optical axis by the pressing force of the leaf spring 325, and the groove 3
The groove side surface 322b of No. 22 is maintained in pressure contact with the cam surface of the eccentric cam 306a.

As a result, the imaging lens 5 is always movable for fine focusing adjustment in the most desirable direction for reading the original image, that is, in the direction to eliminate single-focal blur in the main scanning direction, and at this time, in the optical axis direction. It is intended to be maintained in a state of no play.

After the focus adjustment is completed, the set screw 308 is further screwed in to increase the above-mentioned axial component force Pi and axis orthogonal component force P2, thereby ensuring that the imaging lens 5 is not misaligned with respect to the lens holder 301. At the same time, the rotation of the focus adjustment shaft 306 is stopped.

Next, regarding the CCD2 position adjustment mechanism, see Figures 3 and 4.
The explanation will be given based on FIG. 5, FIG. 12, FIG. 18, and FIG. 19.

First, the inclination in the X-axis direction, which is the main scanning direction of the CCD 2, that is, the rotational fine adjustment mechanism around the Y-axis α, and the rotational fine-tuning mechanism ′Mv& mechanism around the Z-axis, which is the optical axis direction of the imaging lens 5, are as described above. CCD units 1 to 20 each having a metal plate 21 that holds the CCD 2 at a fixed reference position are attached with countersunk screws to two circular pedestals 31d formed on the upper surface of the channel 31 corresponding to the two reference mounting holes 21e. pin 32
It is fixed by screwing it on. As a result, the CCD 2 can be easily replaced within a positional deviation range of 200 to 300 Pm.

The aforementioned CCD 1iJ control board PCB-122 has a rectangular mounting hole 31a formed in the channel 31.
It is positioned so that it protrudes downward from the top.

A substantially cylindrical horizontal shaft 33 is attached to the lower surface side of the right end portion of the channel 31 in the X-axis direction in FIG. 12 so as to extend in the Y-axis direction. This horizontal axis 33 is
Both end portions are cut out into a substantially semi-cylindrical shape, and the plane portions of the semi-cylindrical cutout portions 33C are brought into contact with the lower surface side of the channel 31 and fixed by countersunk screws 34.

Further, two conical portions 33a are formed at the center of the horizontal shaft 33 so as to face each other, and both of these conical portions 33a are inserted into a rectangular notch 31c formed in the channel 31. is housed in. On the other hand, on the upper surface side of the right end portion of the movable base plate 50 in the X-axis direction in FIG. The cylindrical part 35
The lower outer peripheral edge of a is formed on the horizontal axis 33.
It is in contact with the conical inclined side surface of the conical portion 33a at several locations. This allows channel 3 containing COD unit 20 to
1 is adapted to be able to rotate around a horizontal axis 33 and a vertical axis 35.

A square bar 38 is fastened to the left end portion of the channel 31 in the X-axis direction in FIG. They are screwed together. This adjustment screw 39 is
It protrudes downward through a large diameter hole (not shown) formed in the channel 31, and its spherical tip portion 3
9a is the upper surface 50i of the movable base plate 50 having a U-shaped cross section.
is in contact with.

On the other hand, stepped pins 36a and 36b are provided on the front wall 31e and rear wall 31f of the channel 31 in the Y-axis direction.
are screwed into the vicinity of the square rod 38, respectively, and the upper ends of tension springs 37a and 37b are hooked nine times around these stepped pins 36a and 36b, respectively. The lower ends of the tension springs 37a and 37b are hung on stepped pins 54a and 54b screwed onto the front wall 50g and rear wall 5011 of the movable base plate 50, respectively. These tension springs 37a and 37
b extends obliquely at an angle of about 45° with respect to the two axes (optical axis), and its tensile force causes the square bar 3 to
A component force is generated that presses the channel 31 downward and to the right in FIG. 12 at the white area near 8. Then, due to the rightward pressing force by the tension springs 37a and 37b, the lower outer peripheral edge 35a of the cylindrical portion of the vertical shaft 35 is moved into the conical shape of the two conical portions 33a formed on the horizontal shaft 33. In addition to being pressed against the inclined side surface, the lower surface of the cylindrical portion 33b on both end sides of the horizontal shaft 33 is pressed against the upper surface 50a of the movable base plate 50 due to the downward pressing force of the tension springs 37a and 37b. ing. As a result, the entire channel 31 including the CCD Unison 1-20 is held in a three-point supported state via the horizontal shaft 33, the vertical shaft 35, and the movable base plate 5o.

Further, the spherical tip portion 39a of the adjusting screw 39 screwed onto the square rod 38 is brought into pressure contact with the upper surface 50i of the movable base plate 50 by the downward pressing force of the tension springs 37a and 37b. There is. Therefore, by rotating the adjustment screw 39, the channel 31 is rotated and positioned about the horizontal axis 33 around the Y axis, that is, in the α direction.

At this time, the stepped pins 36a and 36b.

Since it is located between the horizontal shaft 33 and the yA adjustment screw 39 and near the adjustment screw 39, the lower surface of the cylindrical portion 33b at both ends of the horizontal shaft 33 is the upper surface 50a of the movable base plate 50.
The two are urged to be pressed more strongly against each other, and the two are brought into close contact with each other without being separated. Further, the biasing force of stepped pins 36a and 36b is
1 is set to such an extent that rotation about the vertical axis 35 is not prevented.

Furthermore, a spring hook portion 38g is formed protruding from the left end portion of the channel 31 in the X-axis direction in FIG. It is hung. On the other hand, a square bar 51 is screwed and fixed to the side surface of the movable base plate 50, and the other end of the tension spring 40 is hung on a stepped pin 52 provided upright on the square bar 51. ing.

Due to the biasing force of the tension spring 40, the channel 31
The whole can be rotated toward the front about a vertical axis 35. Also, the screw hole 5 provided in the square bar 51
An adjustment screw 53 is screwed into 1a, and a spherical tip portion 53a of this adjustment screw 53 is in contact with the front side wall surface 31e of the channel 31 in the Y-axis direction. Therefore, by rotating the adjustment screw 53, the channel 31
is rotated about the vertical axis 35 around the Z axis, that is, in a downward direction, and is positioned.

The fine:A transmission mechanism having such a groove configuration allows for fine adjustment of the inclination in the X-axis direction, which is the main scanning direction, that is, rotational fine adjustment in the α direction around the Y-axis, and in the downward direction around the Z-axis, which is the optical axis direction of the imaging lens 5. Fine rotation adjustment is performed accurately. That is, by first rotating the adjustment screw 39, the tension spring 37
The channel 31 is rotated about the horizontal axis 33 in opposition to the a and 37b, thereby positioning the CCD 2 in the α inclination direction. At this time, since the rotation center position and the adjustment action position are separated,
Fine adjustments can be made without using complicated mechanisms such as differential screws. Note that when adjusting the inclination using the adjustment screw 39, the spherical tip portion 53a of the adjustment screw 53 is slid while being in contact with the front side wall surface 31e of the channel 31 in the Y-axis direction.
Since the perpendicularity of the front side wall surface 31e to the horizontal axis 33 is maintained at the required precision, the channel 31 is hardly rotated around the vertical axis 35 due to sliding movement, and there is no problem in adjustment. There isn't. Further, since the horizontal axis 33 is provided at a position sufficiently apart from the CCD 2,
When adjusting D2 in the α inclination direction, the CCD 2 is hardly displaced in the X-axis direction, which is the main scanning direction.

- By rotating the force adjustment screw 53, the channel 31 is rotated downward around the Z-axis about the vertical axis 35 against the tension spring 40 to perform positioning, and the exposure shown in FIG. The parallelism of the pixel row of the CCD 2 with respect to the line 13 is adjusted. Even in this case, since the rotation center position and the adjustment position are spaced apart, fine adjustment can be made without using a complicated mechanism such as a differential screw. Note that when adjusting the rotation with this adjustment screw 53, the upper surface 50 of the movable base plate 5o
i. The spherical tip portion 53a of the 3A set screw 39 is slid while being in contact with it, and the cylindrical portion 33b of the horizontal shaft 33 is being activated while being in contact with the upper surface 50a of the movable base plate 50. However, since the perpendicularity of the upper surfaces 50i and 50a of the movable base plate 50 to the vertical axis 35 is maintained at the required precision, the above active movement causes channel 3] to become horizontal axis 33.
It is rarely rotated around.

There are no problems with adjustment. Further, since the vertical axis 35 is provided at a position sufficiently spaced from the CCD 2, the CCD 2
During gu in the γ direction around the Z axis, the CCD 2 is hardly displaced in the X axis direction, which is the main scanning direction.

Next, position adjustment of the CCD 2 in the Y-axis direction, which is the sub-scanning direction, and the X-axis direction, which is the main scanning direction, will be explained.

Square bars 55 and 57 are attached to the rear wall 50h of the movable base plate 50 in the Y-axis direction, and these square bars 5
5. Adjustment screws 56° and 58 are screwed to 57. The tip portions of the adjustment screws 56 and 58 are formed into a spherical shape, and the spherical tip portions are connected to the front wall 80 of the rotating base plate 80.
It is abutted on c.

On the other hand, the right side u50d of the movable base plate 50 in the X-axis direction
Fitting holes 50f are formed through the left side wall 50a, and each of these fitting holes 50f is connected to a support shaft 64 extending between a right boss 81 and a left boss 82, which will be described later. It is fitted so that it can slide and rotate freely. Further, as particularly shown in FIG. 4, L-shaped plates S9 and 60 are screwed to the upper sides of the right side wall 50d and left side wall 50e, respectively. One ends of tension springs 61a and 61b are attached to holes 59a and 60a formed at the tips of these L-shaped plates S9 and 60. Further, as shown in FIGS. 3 and 4, the support shaft 64 includes a right lever 62 and a left lever 6.
Fitting holes 62a and 63a are formed in the right lever 62 and left lever 63, to which the lever 3 is rotatably mounted.
The right lever G2 and the left lever 63, which are to be attached to the movable base plate 5°, are arranged on the outside of the right ω'J wall 50d and the left side wall 50e, respectively, of the movable base plate 5°, and their L arm portions 62d and the elongated hole 6 formed in 63d
By engaging locking screws 68 and 69 in 2e and 63s, rotation of right lever 62 and left lever 63 with respect to support shaft G4 is respectively restrained. The locking screws 68 and 69 are screwed into the right side wall 80a and the left side wall 80b of the rotating base plate 8o, respectively, so as to penetrate in the X-axis direction.

Further, holes 62C and 63c are formed in the middle block portion 62b and G3b extending in a direction perpendicular to the upper arm portions 62d and 63d, that is, toward the front wall 80c of the rotating base plate 80. , these holes 62c and 63
One ends of the tension springs 61a and 61b described above are hung on c.

In the state shown in FIG. 4, the tension spring 61a
and 61b are energized.

The movable base plate 50 tries to be rotated around the fourth power by the urging force of the tension springs 61a and 61b, but:A
The spherical tip portions 56a, 58a of the setting screws 56, 58 are pressed against the front wall 80c of the rotating base plate 80, so that they are stopped. The tension spring 61a is extended so that its biasing force generates component forces in the tangential direction and the normal direction around the support shaft 64, whereby the movable base plate 50 is urged against the support shaft 64. , will be held in a fixed position.

Further, as shown in FIG. 6, a lower arm portion 62f is formed below the right lever 62, and a bent portion provided on this lower arm portion 62f forms a right side wall 50d of the movable base plate 5o.
is in contact with the lower edge of the

When the CCD unit 2o is rotated toward the front to the state shown in FIG. 6 for maintenance or replacement, the tension spring 61a, which is in a predetermined deenergized state, is held so as not to fall off. It has become so. Further, around the fitting holes 62a and 63a formed in the right lever 62 and the left lever 63, circular arc holes 62g, 62h and 63g, 63h are provided so as to face each other. 62g and 63
An adjustment screw 83 is passed through G in a non-contact manner, and locking screws 73 are loosely fitted into the other arcuate holes 62h and G3h.

The fine adjustment mechanism having such a configuration allows precise position movement fine adjustment in the Y-axis direction, which is the sub-scanning direction. That is, by rotating the adjustment screws 5G and 58, the movable base plate 5o is rotated about the support shaft 64 against the tension springs 61a and 61b, thereby positioning the CCD 2 in the Y-axis direction. It has become. At this time, since the rotation center position and the adjustment action position are spaced apart from each other compared to the distance between the rotation center position and the CCD 2, fine adjustments can be made without using a complicated mechanism such as a differential screw. be able to. Note that this adjustment screw 56.
The movement adjustment operation in the sub-scanning direction by 58 is performed by a rotational movement around the support shaft 64, but the CCD 2 is spaced apart from the support shaft 64 and the amount of movement for position adjustment is 1. Since ~2III11,
There is no problem because the deviation in the inclination β direction of the CCD 2 in the sub-scanning direction is extremely small. Also, as in this example, the pixel size is extremely small (7 μm x 7 μrn).
When a linear sensor is used, the slight inclination β of the pixel row in the sub-scanning direction does not pose any problem in reading the projected image. Rather, it is preferable to slightly tilt the CCD 2 in the sub-scanning direction with respect to the optical axis, since this prevents the reflected image of the projected image by the cover glass 2b of the CCD 2 from being re-projected onto the pixel row.

Furthermore, fitting holes 81a and 82a are formed through the center portions of the right boss 81 and the left boss 82, which are screwed to the right side walls 80a and 80b of the rotating base plate 80, respectively. Both end portions of the support shaft 64 are fitted into the holes 81a and 82a, and are locked by set screws 81b and 82b.

Further, a compression spring 65 is fitted to the outside of the support shaft 64 . One end portion of this compression spring 65 is attached to the movable base plate 50.
The compression spring 65 is supported on the inner surface of the right side wall 50d, and the other end portion of the compression spring 65 is pressed into contact with a pin 67 fixed through a support shaft 64 via a washer 66 and locked. As a result, the movable base plate 50 is urged toward the right in FIG. 3, that is, toward the right boss 81. On the other hand, the right boss 81 has an adjustment screw 8.
3 are screwed together so that they pass through, and this adjustment screw 83
A spherical tip portion 83a of the movable base plate 5o is in contact with the right side wall 50d of the movable base plate 5o. Movable base plate 5 by the compression spring 65
With a moving force of 0, the right side wall 50d of the movable base plate 5o becomes: J
It is adapted to be pressed into contact with the spherical tip portion 83a of the 3m screw 83. Therefore, by rotating the adjustment screw 83, the movable base plate 5o is moved in the main scanning direction. The thread pitch of the adjustment screw 83 is 0.5 [l
In order to satisfy the position adjustment accuracy of 63.5 μmti for the pixel row 2a of the CCD 2, it is only necessary to rotate the adjustment screw 83 with an accuracy of about 45 degrees, making the adjustment operation extremely easy. is now being carried out. The main scanning direction (X
During the adjustment operation (in the axial direction), the position of the CCD 2 must not shift in the sub-scanning direction (Y-axis direction), main-scanning tilt direction (α direction), direction around the optical axis (γ direction), or Z-axis direction. do not have. This is configured such that the base of the right angle between the support shaft 64 and the optical axis of the imaging lens 5 can be adjusted with an accuracy of ±1', and the exposure line 13 of the original image on the support shaft 64 is adjustable.
Similarly, the parallelism with respect to the
b is pressed in the radial direction of the support shaft 64, and at the same time the front wall 8 of the rotating base plate 8Q is
This is because the position of the movable base plate 5o is maintained by 0c.

Also, as in this embodiment, the dimensions of the pixel row 2a of C0D2 (
35 nm), the support shafts 64 are spaced sufficiently apart (180 mm
), the positional accuracy of the right boss 81 and left boss 82 supporting the support shaft 64 in the sub-scanning direction (Y-axis direction) is within the normal machining accuracy (for example ±O, ln
a), the position adjustment amount of CCD2 in the main scanning direction X is 2m.
The positional deviation in the sub-scanning direction (Y-axis direction) with respect to n+ is 2μ
It is about n1 and there is no problem in adjustment.

Next, the original 1i! shown in FIG. A mechanism for adjusting the perpendicularity of the optical axis of the imaging lens 5 with respect to the li exposure surface, that is, the plane for reading the original 12 with the exposure line 13 will be described.

As shown in FIG. 3, FIG. 4, and FIG. A hole 96 is formed perpendicular to the axis, and this hole 96
A conical shaft 94 is fitted into the front wall 80c, and the conical shaft 94 is tightened by a cylindrical female screw 95 and fixed at right angles to the front wall 80c. Further, the rotary base plate 80 is arranged so as to face the front wall 100a of the base plate 100, which is formed in a U-shape in cross section. The large diameter side of the conical shaft 94 penetrates through the circular arc hole portion 120a of the mating hole 120 (see FIG. 5(b)) and protrudes inside the white board 100. At this time, the engagement hole 1
The twenty circular arc hole portions 120a are formed to be smaller than the maximum diameter of the conical portion of the one conical shaft 94 and larger than the minimum diameter, and the conical inclined surface 94a of the conical shaft 94 is formed in the engagement hole 1.
20 is engaged with the circular arc hole portion 120a. As a result, the rotating base plate 80 is
is rotatable about a conical shaft 94.

On the other hand, a pedestal 101 is welded to the front wall 100a of the base plate 100 on the right side in FIG.
An adjustment screw 102 is screwed into the screw hole formed in 1 so as to penetrate therethrough.

The spherical tip portion 102a of the adjusting screw 102 is in contact with the upper surface 90a of the square rod 90 that is welded to the right side wall 80a of the rotating table plate 8o. Further, a stepped pin 9 is provided on the left side portion of the front wall 100a of the base plate 100 in FIG.
3 are erected, and stepped pins 1 are erected on the left side wall 80b of the rotating base plate 80, and a tension spring is inserted between these stepped pins 93 and 91. 92 is being passed around. As a result, the base plate 10
The rotating base plate 8o is connected to the conical shaft 94 with respect to the front wall 100a of
The third member is rotated counterclockwise around , and
The upper surface 90a of the square rod 90 welded to the right side wall 8°a of the rotating base plate 80 is connected to the spherical tip portion 1 of the adjusting screw 102.
02a, and the rotating base plate 8o is stopped.

At this time, the conical shaft 94 is pressed downward perpendicularly to the conical shaft 94, but as described above, the conical inclined surface 94a of the conical shaft 94 By engaging with the conical shaft 94, the conical shaft 94 receives a component force directed to the left in FIG. 5, and this component force presses the rotating base plate 80 toward the base plate 100. Also, the base plate 1
On the front face Ml 100a of 00, three circular pedestals 100f are formed on the circumference centered on the conical axis 94 at an equal pitch of approximately 12o°, and on these circular pedestals 100f there are rotatable pedestals 100f. The outer surface of the front wall 80G of the base plate 8o is brought into contact with the rotary base plate 80 to support it at three points, thereby allowing the rotary base plate 80 to rotate stably.

In addition, three elongated holes 84, 85, 86 are formed in the front wall 80c of the rotating base plate 80 at an equal pitch of approximately 120° on the circumference centered on the conical shaft 94. Set screws 86, 87° 88 passing through elongated holes 84, 85, 86 are screwed onto the front wall 100a of the base plate 1oO to fix the rotating base plate.

Therefore, if the adjusting screw 102 is rotated with the setscrews 86, 87, and 88 loosened, the rotary base plate 80 will be rotated about the conical shaft 94, and the perpendicularity of the optical axis of the imaging lens 5 will be will be adjusted.

In the optical axis perpendicularity adjustment operation using the adjustment screw 102, the position of C0D2 is the main scanning direction (X-axis direction), the sub-scanning direction (Y-axis direction), the main scanning tilt direction (α direction), and the direction around the optical axis. No deviation occurs in either the γ direction or the Z axis direction. Further, the three-point support structure of the rotating base plate 80 prevents the rotating base plate 8o from deforming.

In the perpendicularity adjustment mechanism in the sub-scanning direction between the optical axis of the imaging lens 5 and the original image exposure surface, as shown in FIGS. 14, 15 and 16, the base plate 100
is screwed onto the front wall 200a of the base 200, and three circular pedestals 203 are welded to the front wall 200a, and a left side plate is welded to the left and right ends of the pedestals 203, respectively. 213 and the right side plate 21G, a left main shaft 215 and a right main shaft 217 are attached to be coaxially arranged. Two shafts 214 are provided at positions symmetrical to the left main shaft 215 on the left side plate 213 so that they are parallel to the left main shaft 215 and their axes are arranged on the same plane. Further, the left support frame 230 and the right support frame 231, which are provided as immovable members with respect to the original exposure line 13, have a left support frame 230 and a right support frame 231, which support the base 200 rotatably around the left main shaft 215 and the right main shaft 217. Support plate 218 and right support plate 225 are each welded.

A recess 218a is formed in the center of the left support plate 218, and a bottom surface 21 of the recess 218a
A bearing portion 218b having an arcuate cross section is recessed in the center portion of 8f. The left main shaft 21 is attached to this bearing portion 218b.
5 is fitted.

Further, the left main shaft 21 is located at the bottom surface 218f of the recess 218a.
A square bar 219 for positioning 5 is fixed by two setscrews 220. - Groove 21 on the power wood main shaft 215
5a is formed in an annular shape, and when the square rod 219 is brought into contact with the groove bottom 215b of this annular groove 215a, the upper left shaft 215 is positioned in an immovable state in the left and right main axis direction, that is, the main scanning direction (X-axis direction). It is becoming regulated.

Also, a set screw 22 is screwed onto the square rod 219.
1 is pressed against the groove bottom 215b of the groove 215a.

Furthermore, grooves 318c and 218d are formed in the upper and lower end portions of the left support plate 218 to accommodate the shaft 214 in a loosely fitted state.

Adjustment screws 222 and 223 to press the shaft 214.
are screwed onto the upper and lower end portions of the left support plate 218, respectively. And the above yA setting screws 222, 223
By rotating the left support plate 218, the left support plate 218 is rotated about the biaxial axis.

Further, a bearing portion 225a having an arcuate cross section is recessed in the center portion of the right support plate 225.
A right main shaft 217 is fitted into the main shaft 217 . Also, the right support plate 22
5 has a square rod 22 for positioning the right main shaft 217.
6 is fixed by two set screws 226 , and the tip of the set screw 228 screwed onto the square bar 226 is pressed against the surface of the right main shaft 217 .

In FIG. 15, the optical axis of the imaging lens 5 is the axis 214.
The imaging lens 5 is set parallel to the straight line connecting the axis of the left main axis 215 and the left main axis 215, and extends in the sub-scanning direction through the left main axis 215 and the right main axis 217.
The optical center of the imaging lens 5 is arranged, and the optical axis position of the imaging lens 5 is arranged near the left and right axes. In such a configuration, if the adjusting screws 222 and 223 are rotated, the optical axis of the imaging lens 5 is rotated integrally with the base 200, and the inclination in the sub-scanning direction (Y-axis direction) is adjusted. It will be fine-tuned. As a result, the perpendicularity between the optical axis of the imaging lens 5 and the i-document exposure surface in the sub-scanning direction is adjusted by a slight angle of A.

In such an adjustment operation, the imaging lens 5 does not shift in the main scanning direction (X-axis direction) or in the inclination direction (α direction) of the main scanning direction. Further, after adjusting the inclination of the optical axis of the imaging lens 5 in the sub-scanning direction, the ratio 221.
228 and adjusting screws 222, 223
0 is fixed in position, and therefore the position of the imaging lens 5 is fixed.

Next, lens unit 300 and COD unit 2o
The mechanism for adjusting the movement of the lens in the optical axis direction will be described below.

Next, lens unit l-300 and CC'D Uniso h
The movement adjustment mechanism in the optical axis direction of lens No. 20 will be described.

In FIGS. 1, 2, 3, 4, and 14, the left support frame 230 and the right support frame 230 are provided as immovable members with respect to the exposure line 13 of the original image, as described above. With respect to the frame 231, the base 200 is aligned with the exposure line 1.
A left main shaft 215 and a right main shaft 2 which are parallel to and coaxial with 3.
This base 20
Fitting holes 201 and 202 are respectively formed in the upper side Q200b and lower side u200c of 0 so as to face each other. These fitting holes 201 and 202 are provided with the upper left shaft 2.
31 and the upper right shaft 217, the support shaft 113 is fitted and inserted so as to be perpendicular to both the axes. On the other hand, the upper wall 100b and the lower wall 100c of the base plate 100 are provided with both fitting holes 20.
Elongated holes 111 and 112 extending in the sub-scanning direction are formed at positions corresponding to 1 and 202, respectively, and both upper and lower end portions of the support shaft 113 are fitted into these elongated holes 111 and 112. . Also, the upper plate 10 of the support shaft 113
Retaining rings 114 are respectively locked on the upper and lower sides of the upper wall 100b and lower wall 100C of 0, and this allows the support shaft 113 to slide along with the base plate 100 in the optical axis direction of the imaging lens 5. It will be supported as possible.

At this time, the base plate 100 is movable in the sub-scanning direction (Y-axis direction).

In addition, it remains stationary in the main scanning direction (X-axis direction).

Furthermore, among the three circular pedestals 203 welded to the front wall 200a of the base 200, two circular pedestals 203 are placed apart from each other by a predetermined distance on a line parallel to the axis of the support shaft 113. Along with the remaining one circular pedestal 20
3 is arranged on a line parallel to the axes of the left main shaft 215 and right main shaft 217. The surface portions of these three circular pedestals 203 are formed so as to be arranged in the same plane, and are each formed with a female thread portion 203b into which a screw 104, which will be described later, is screwed. On the other hand, on the front wall 100a of the base plate 100.

Three vertically elongated holes 103 are formed at positions corresponding to the three circular pedestals 203, and each of these elongated holes 10
The screw 104 passes through the inside of 3. A compression spring 10G is attached to the outside of the screw 104, and a tube 105 is attached to the outside of this compression spring 106.

One end of the compression spring 106 is connected to the screw 1 through the washer 107.
04, and the other end of the compression spring 106 is connected to the base plate 10 via a washer 108.
It is pressed to 0. As a result, the base plate 100 is pressed toward the circular base 203.

The base plate 100 is slidable along the support shaft 113 in the direction of the lens optical axis while being pressed against the circular base 203 by the biasing forces of three compression springs 10G. At this time, the base plate 100 remains stationary in the sub-scanning direction.

Further, a square bar 109 is screwed to the right end of the upper wall 100b of the base plate 100 near the support shaft 113, and an am screw 11oh is screwed into this square bar 109 so as to pass through the square bar 109. . The spherical tip portion 110a of the 'A setting screw 110 passes through a large diameter hole (not shown) formed in the base plate 10 and connects to the upper wall 200 of the base 200.
b.

In this embodiment, a base plate 100, a rotating base plate 80 attached to the base plate 100, a lens unit 300, a CCD unit 20, and a CCD unit 20 attached to the rotating base plate 80 are used.
Due to the weight of the CD base plate unit 30, support shaft 64, etc.
The force that presses and slides the base plate 100 downward along the support shaft 113 becomes greater than the frictional resistance force between the front wall 100a of the base plate 100 and the front surface 203a of the circular pedestal 203 due to the pressure of the three compression springs 106. Therefore, no spring is used to press and bias the base plate 100 downward. However, if necessary, 5, for example, the lower wall 1 of the base plate 100,
00c and the lower wall 200c of the base 200,
It is also possible to arrange the compression spring so that it is inserted into the support shaft 113.

In such a configuration, by rotating the adjustment screw 110, the base plate 100 is finely adjusted and moved along the support shaft 113 while in contact with the circular base 203. Therefore, by moving the adjusting screw 110 back and forth, the lens unit 300 and the CCD unit 20 can be finely adjusted in the direction of the lens optical axis without causing any mutual positional deviation. And with this, exposure line 1
Fine adjustment of the distance between CCD 3 and CCD 2, that is, the conjugate length (L in FIG. 2) at a predetermined projection magnification, can be easily and accurately performed. Furthermore, during such adjustment, the imaging lens 5 and C0D2 are adjusted in the main scanning direction (X-axis direction), sub-scanning direction (Y-axis direction), rotation direction around the lens optical axis (γ direction), and main scanning direction (X-axis direction), sub-scanning direction (Y-axis direction), No deviation occurs in the direction of inclination in the scanning direction (α direction) or in the direction of inclination in the sub-scanning direction (β direction).

Next, the light shielding and dustproof seal structure of the CCD 2 will be explained.

3 and 5, a sealing body 31 is attached to the lower part 301d of the lens holder 301 of the lens unit 3o○.
0 is fitted with an upper plate 311 that is adhesively fixed.

The upper plate 311 is formed with a bent portion 311a for positioning in the main scanning direction and the sub-scanning direction. On the other hand, the lower side of the seal body 310 is bonded to a lower plate 312, and this lower plate 312 is formed with a notch 312a that engages with two countersunk screw pins 32 that screw the CCD unit 20 into the channel 31. has been done. The seal body 31
0 is attached and positioned so as to shield the peripheral area outside the imaging optical path of the imaging lens 5 between the lens holder 301 and the metal plate 21 that adhesively holds the CCD 2.

The seal body 310 is made of a soft foamed resin having fine mesh and light-shielding properties and air permeability formed into a rectangular tube shape, and its elastic force allows the lens holder 301 and the metal plate 2 to be attached to each other.
1 through an upper plate 311 and a lower plate 312.

No gaps are formed between the upper plate 311 and the lens holder 301 and between the lower plate 312 and the metal plate 21. With such a seal body 310, C0D2
External light that would degrade the image reading signal is blocked, and the adhesion of dirt, dust, etc. to the CCD 2 is prevented.

Further, the sealing body 310 is made of a material and having a shape and dimensions that do not impair air permeability, so that interference and deterioration of the image reading function of the CCD 2 can be sufficiently prevented. Furthermore, the hardness and size of the seal body 310 are such that the lens holder 301 or the metal plate 21 will not be deformed or misaligned with each other due to the elastic force of the seal body 310, and the lens holder 301 and the metal plate It is set to the extent that it can be explained from between 21 and 21. Therefore, the sealing body 310 in which the upper plate 311 and the lower plate 312 are vertically bonded can be easily attached and detached between the lens holder 301 and the metal plate 21, and the upper plate 31
1 and the lower plate 312, and when adjusting the position of the metal plate 21 with respect to the lens holder 301, the mounting position does not shift, and the flexibility of the seal body 301 prevents the lens from shifting. This prevents excessive force from being applied to the holder 301 and the metal plate 21.

In the cooling system shown in FIG. 5(a), the air that is forced to be blown by a blower 206 is filtered by a dust filter 208 attached to a duct 207, and then filtered to the base. flowed into the stand 200,
From the square hole 205 of the base 200 to the square hole 100g of the base plate 100
It passes through the square hole 80e of the rotating base plate 80 and is sprayed directly onto the sealing body 310, the lower part of the CCD 2 (7), and the PCl 3-122. This blower 2
The air blowing action of 06 is controlled based on a temperature detection signal of the CCD 2 emitted from a thermistor 25 that is in contact with and bonded to the back surface of the CCD 2.

With such a cooling device of the COD unit 2o, C
This prevents expansion and deformation of the CCD 2 due to heat generated from the 0D2 itself or the PCB-122 soldered to the CCD 2. This prevents image reading errors from occurring, and also prevents the electronic components on the PCB-122 from expanding or deforming. Malfunctions due to heat generation are also prevented.

Although the CCD 2 installed in the document reading device is designed to prevent dust such as dust from adhering to the surface of the cover glass 2b, it may interfere with normal reading during long-term use. Since dirt and dust may adhere to the surface, it is desirable to clean it as necessary. Furthermore, it is desirable that the CCD 2 be constructed so that it can be easily replaced if it breaks down or its performance deteriorates for some reason.

Therefore, in this embodiment, the mounting member of the CCD 2 is rotatable in the sub-scanning direction, and a CCD unit 20 is formed in which the CCD 2 is integrally formed with a metal plate 21 which is a holding member thereof. A configuration is adopted in which it is retracted to the outside, which facilitates attachment and detachment to the member. Further, when simply cleaning the C0D 2 without replacing it, the CCD unit 20 is configured to expose the CCD unit 20 at an angle to the front, so that the cleaning operation can be performed extremely easily. Furthermore, even when cleaning the CCD unit 20 or replacing the CCD unit 20, the position of the mounting member for the CCD 2 is configured to be accurately returned to its original position by the biasing force of an adjustment screw and a spring, and the dimensions of the CCD unit 20 are The structure is such that fine adjustments due to the above variations can be made extremely easily.

That is, as shown in FIGS. 3, 4, and 6, the tip of the screw 68 screwed into the right side wall 80a of the one-turn base plate 80 is connected to the upper arm 52d of the right lever 62. Although the right lever 62 is retracted to the position where it is removed from the provided elongated hole 62e, the right lever 62 is rotated around the sixth tip around the support shaft 64 by the biasing force of the tension spring 61a, so that the right lever 62 The bent portion of the lower arm portion 62f of the movable base plate 5o is brought into contact with the lower edge of the right side wall 50d of the movable base plate 5o.

As a result, the movable base plate 5o and the support shaft 6 of the right lever 62
The relative position around 4 is made stable. Similarly, when the screw 69 screwed into the left side wall 80b is removed from the elongated hole 63e of the upper arm 63d of the left lever 63, the bent portion of the lower arm 63f of the left lever 63 is attached to the movable base plate 50.
will come into contact with the lower edge of the left side W 50 e,
The relative positions of the movable base plate 50 and the left lever 63 around the support shaft 64 are made stable.

In this state, as shown in FIG.
The movable base plate 50 on which the D units 1 to 2o are attached can rotate integrally with the right lever 62 and the left lever 63 to the outside of the projection optical path of the imaging lens 5, but its rotation range is limited to the above-mentioned range. The circular hole 6 of the right lever 62 is connected to the screws 73 and 74 that are screwed into the right boss 81 and the left boss 82, respectively.
2h and one end of the arcuate hole 63h of the left lever 63 are brought into contact with each other to be regulated. In this state, the CCD unit I-20 is exposed at the front of the apparatus, and cleaning of the C0D2 and replacement and attachment/detachment of the COD unit 20 are extremely easy. Furthermore, in this state, the movable base plate 50 on which the CCD unit 20 is attached is
The circular arc hole 62g of the right lever 62
The position and size of the circular arc hole 62g are set so that the adjustment screw 83 is not brought into contact with the adjustment screw 83, thereby preventing the device from shifting or deforming due to excessive force being applied to the adjustment screw 83. It has become. At this time, the holding member (channel 31 in FIG. 3) of the CCD unit 20, which is held so as to be adjustable in position with respect to the movable base plate 50, is maintained in a completely unchanged state with respect to the movable base plate 50.

After completing the necessary work such as cleaning and replacing the CCD 2 and CCD unit 20, the movable base plate 50 is rotated back to its original position. That is, if the right lever 62 and the left lever 63 are locked in predetermined positions by screws 68 and 69, respectively, the tension springs 61a and 6
The movable base plate 50 is rotated around the support shaft 64 by the biasing force of the movable base plate 1b. The plate 50 is returned to its original position accurately. Also at this time, the movable base plate 5o
The right side wall 50cl is also brought into contact with the adjustment screw 83 at its original position, so that its position in the main scanning direction can also be accurately returned to its original position.

In the image reading apparatus according to the embodiment of the present invention, the position adjustment of the COD with respect to the imaging lens, the imaging lens 5. A position adjustment mechanism is used to adjust the position of C0D2, etc., using the steps of the screw. That is, in this embodiment, a means for pressing the male thread and the female thread in the radial direction is used in order to prevent problems in fine adjustment due to play in the axial and radial directions of the screw.

As shown in FIGS. 17 and 18, the square bar 3
8 and the movable base plate 5o are urged toward each other by a tension spring or gravity, and an adjustment screw 39 is screwed into a female thread 38a formed in the square bar 38. The hemispherical tip portion 39a of this adjustment screw 39 is in contact with the upper surface 50i of the movable base plate 50.

The mutual positions of the square rod 38 and the movable base plate 50 are determined by the cooperation of tension springs or gravity. Also, a female thread 38 formed on the square bar 38
A female thread 73 is formed in a direction perpendicular to the screw axis of a, and has a diameter equal to or slightly smaller than the root diameter of this female screw 73, and a length approximately equal to the root diameter of the female screw 73. A cylindrical brake 71 made of a nylon ring is fitted into the female thread 73. A set screw 72 is screwed into the female thread 73 from behind the brake element 71, and a planar tip 72a of the set screw 72 presses the brake element 71.

The planar tip 72a of the set screw 72 is connected to the brake member 71.
When the set screw 72 is screwed in even more firmly from the state where it is in contact with the nylon ring brake 71.

The tip portion of the brake 71 is pressed against the adjustment screw 39 while undergoing compression deformation, and the tip portion 71a of the brake 71 bites into the threads and valleys of the adjustment screw 39.
The peripheral surface 71b in contact with the female thread 73 also undergoes plastic deformation so as to bite into the threads and valleys of the female thread 73. In this state, the male thread of the adjusting screw 39 presses the female thread 38a in the radial direction, and the axial center of the adjusting screw 39 is maintained slightly deviated from the axial center of the female thread 38a. The shaft center position can be rotated without shifting due to rotation. Therefore, the adjusting screw 39
The tip 39a of the screw is not moved in the radial direction of the screw. When rotating the G3 adjusting screw 39, which has a male thread that engages with the female screw 38a, the relative position between the square bar 38 and the movable base plate 5o is adjusted by yA depending on the steps of the adjusting screw 39. The contact position of the tip end 39a of the adjusting screw 39 with respect to the upper surface 50i of the movable base plate 50 does not shift due to play in the engagement between the yA adjusting screw 39 and the female screw 38a.

Furthermore, when the nylon ring brake 71 is plastically deformed as described above, elastic stress is generated within itself, so the brake 71
1 and the setscrew 72 are prevented from unintentionally loosening. Further, the braking force applied to the adjusting screw 39 by the pressing force of the brake element 71 does not change regardless of whether the adjusting screw advances or retreats, and can be further adjusted as necessary.

In such a construction, the set screw 72 is further screwed in after the relative position between the movable base plate 50 and the square bar 38 is adjusted by advancing and retracting the g adjustment screw 39, and thereby the brake 71 is further screwed in. The adjustment screw 39 is pressed and deformed into a female thread 3
8a. In this case, the set screw 72
The adjustment screw 39 will not be displaced from the female thread 38a by screwing in. Therefore: A set screw 39
No other fastening means are required to lock the to the female thread 38a.

If the adjusting screw 39 has been rotated for some reason and it becomes necessary to readjust the mutual positions of the movable base plate 50 and the square bar 38, loosen the set screw 72 slightly and adjust the position of the brake 71 relative to the adjusting screw 39. Reduce the pressing force. By doing this, the adjusting screw 39 is rotated with its axial center position maintained at a predetermined position by the required pressing force, and the threaded portion of the adjusting screw 39 is not damaged at all. Therefore, the smooth rotation of the adjusting screw 39 is not hindered in any way.

The position adjusting device constituted by the yA setting screw 39, the square bar 38, the upper surface 501 of the movable base plate 5o, the brake 71 and the set screw 72 is similar to other position adjusting devices, that is, the adjusting screws 53, 56, 58. The same method is adopted in a position adjustment device using ゜102.110.83.

[Effects of the Invention] As described above, according to the present invention, when positioning an imaging lens, adjustment can be performed without moving the imaging lens and the adjustment shaft for positioning the imaging lens in the radial direction. This allows fine focusing adjustment of the imaging lens to be performed easily and with high precision.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view showing the main parts of the optical system of an apparatus in an embodiment of the present invention, and Fig. 2 shows a set of imaging lenses and C
Fig. 3 is an explanatory front view of a set of CCDCCD reading unit 1, and Fig. 4 and Fig. 5 (a) are shown in Fig. 3. FIG. 5(b) is a front explanatory view showing the shape of the hole provided in the base plate; FIG. The figure is a side partial cross-sectional view showing the CCD reading unit in an open state, Figure 7 is a plan view showing the CCD positioning and fixing structure, and Figure 8 is A-A'g in Figure 7.
9 is an explanatory plan view showing another embodiment of the COD positioning and fixing structure, FIG. 10 is an explanatory cross-sectional view taken along line BB' in FIG. 9, and FIG. is COD
FIG. 12 is an exploded perspective view showing a CCD fine adjustment structure, and FIG. 13 is an imaging lens focus adjustment mounting structure. FIG. 14 is a front explanatory view showing the reading unit shown in FIG. 3 removed from the base, and FIG. 15 is taken along the line AA' in FIG. FIG. 16 is a cross-sectional view taken along line BB' in FIG. 14, and FIGS. 17 and 18 are cross-sectional views showing the locking structure of the adjustment screw. 1.2.3...CCD, 4,5.6...Imaging lens, 12...Original, 13...Exposure line, 15...
Reading unit, 20... COD unit, 300...
・Lens unit, 301...Lens holder 30
6... Adjustment shaft, 306a... Eccentric cam, 321...
・Lens barrel, (1 other person) Shape q Figure 2 β Tei 40 mouths bl I circle? Ulσ shape 4D scale Je figure 47 Figure 1 4

Claims (1)

[Claims] 1. A document image is projected onto a photoelectric conversion element by an imaging lens, and the document image is read photoelectrically by relatively moving the document image and the photoelectric conversion element in a sub-scanning direction. In the position adjustment mechanism of the image reading device, the lens barrel support holder accommodates the lens barrel of the imaging lens, and the lens barrel support holder is movable in an axial direction perpendicular to the axis of the imaging lens barrel and rotates about the axis. an adjustment shaft that is freely held in the lens barrel support holder; an eccentric cam mechanism that moves the lens barrel of the imaging lens in the optical axis direction based on rotational movement of the adjustment shaft around the axis; and the adjustment shaft. An image reading device comprising: a pressing means for pressing a shaft in an axial direction toward the imaging lens side and in a direction orthogonal to the shaft; and a focusing adjustment device comprising each of the following components. position adjustment mechanism. 2. An image reading device that projects an original image onto a photoelectric conversion element using an imaging lens, and moves the original image and the photoelectric conversion element relative to each other in the sub-scanning direction to photoelectrically read both images of the original. The position adjustment mechanism includes: a lens barrel support holder that accommodates the lens barrel of the imaging lens; an adjustment shaft held by the lens barrel support holder; an eccentric cam mechanism that moves the lens barrel of the imaging lens in the optical axis direction based on rotational movement around the axis of the adjustment shaft; a pressing means for pressing in an axial direction toward the lens side and a direction perpendicular to the axis; and a rotating member for pressing the barrel of the imaging lens in the direction of the optical axis and regulating the barrel of the imaging lens in a direction around the optical axis. 1. A position adjustment mechanism for an image reading device, comprising: a stop means; and a focus adjustment device comprising each of the following components. 3. In the position adjustment mechanism for an image reading device described in claims 1 and 2, the pressing means for pressing the adjustment shaft in the axial direction toward the imaging lens side and in the direction orthogonal to the axis is configured to press the adjustment shaft in one direction. 1. A position adjustment mechanism for an image reading device, comprising means for decomposing a pressing force directed toward an imaging lens into an axial component force toward an imaging lens and a component force in a direction orthogonal to the axis.