JPH033554A - Image reading device position adjustment mechanism - 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 a document to be read in general is limited to a maximum of A3 size, but 1
．． In certain fields such as industrial drawings, the target manuscript size is 841ngn (JIS AO size) to 3671ngn (941no) (ANSI E
Some of them are larger, such as size). For such large documents, it is impossible to reduce and project the image onto a single photoelectric conversion element (hereinafter referred to as CCD) and read the image, so conventional general office reading devices cannot provide sufficient images. It is not possible to read by 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 reading device, for example, the CCD is positioned and arranged so that the main scanning direction of each COD perfectly matches the width direction of the original image. It is impossible to photoelectrically read the original image unless the original image and the photoelectric conversion element are moved relative to each other in the sub-scanning direction. In particular, high-density CCD linear sensors used when high-density reading is required are highly accurate due to the relationship with the projection magnification for each COD, the amount of reading overlap, and even temperature changes. Adjustments must be made.

Conventionally, JP-A-62-48940, JP-A-51
-51217 publication or Utility Model Application Publication No. 61-171353
Although it has been proposed to install the CCD and the printed circuit board separately in order to facilitate the support and replacement of the CCD in the above publications, this does not fully meet the above-mentioned requirements.

SUMMARY OF THE INVENTION An object of the present invention is to provide a position adjustment mechanism for an image reading device that allows a COD and a printed circuit board to be installed separately in good condition.

[Means for Solving the Problems] In order to achieve the above object, the present invention projects an original image onto a photoelectric conversion element using an imaging lens, and also moves the original image and the photoelectric conversion element relative to each other in the sub-scanning direction. In the position adjustment mechanism of an image reading device that photoelectrically reads a document image by causing the photoelectric conversion element to hold a first printer 1-substrate having a function of amplifying and outputting a read signal by the photoelectric conversion element, A configuration is provided in which a second printed circuit board having a circuit for electrically controlling a photoelectric conversion element and the first printed circuit board are connected by a flexible cable.

[Function] In the means having such a configuration, the read signal from the photoelectric conversion element is amplified and outputted by the first printed circuit board, and then the second printed circuit board having a circuit for electrically controlling the photoelectric conversion element is outputted. It is designed to be emitted via a flexible cable.

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

As shown in FIG. 1, a document 12 is illuminated by a long illumination lamp 11, and an image on the document 12 is thereby formed in an exposure line 13 by three imaging lenses 4,
5.6, one-dimensional photoelectric conversion device (hereinafter referred to as CCD)
(abbreviated as )) is projected onto a pixel column of L, 2°3.

Each of the light beams 7°8.9 in the imaging lenses 4, 5.6 is distributed over a predetermined area Q z 12 in the exposure line 13.
za are overlapped, and the CCDI, 2,
When the read signal according to No. 3 is output to a writing device (not shown), control is performed so that dropouts, duplications, shifts, etc. do not occur 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.

'Also, as shown in FIG. 2, the area Q2 on the exposure line 13 of the document 12 is
, 1102 times, and is imaged on the pixel row of the CCD 2. The CCD 2 is a linear sensor having 5000 pixels of 7 μm×7 μm, and the length of one pixel row is set to 35 nwn. Therefore, the length of the region Q2 is 317.5
It will be done in nn. Here, if the width of the original 12 on the exposure line 13, that is, the maximum reading width Ω, is 914.4 am, then the overlap amount Ω on the exposure line 13 is 2-
Q2. is G, 35++o, and pixel row 2 of CCD 2
On a, 0.7nan (100 pixels) tonal.

In this way, the image of the original 12 is transferred to multiple CCDIs.

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 so as to be able to move finely in parallel in the optical axis direction (Z-axis direction), and this base plate 100
A rotating base plate 8o is mounted on the optical center of the N-image lens 5 for fine rotational adjustment around a conical shaft 94 that is perpendicular to the optical axis and has an axis in the sub-scanning direction; A shading correction plate 97 is screwed to the upper wall 80d of the rotating white plate 80 so as to be movable in a direction perpendicular to the optical axis, and an optical sensor of the imaging lens 5 is installed approximately in the center of the front side wall 80c of the rotating base plate 80. A lens unit 300 is screwed at the center for fine rotational adjustment around a conical shaft 94 that is perpendicular to the optical axis and has an axis in the sub-scanning direction, and a right side wall 80 a of the rotary base plate 80 . A support shaft 64 is hung between a right boss 81 and a left boss 82 that are screwed to the lower part of the left u80b, and a support shaft 64 that can be rotated and finely adjusted and slid in the axial direction. It consists of a CCD base plate unit 30 which is mounted for fine adjustment.

The CCD unit 20 is held on the upper Mi2 CCD base plate unit 30, and a sealing member 310 having light-shielding properties, dust-proofing properties, and air permeability is installed between the CCD unit 20 and the lens unit 300. There is.

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 an upper left 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. Further, two stop shafts 214 are provided on both sides of the left main 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.

As shown in FIGS. 7 and 8, the CCD-L knit 20 (7) CCD 2 is fitted into a substantially rectangular positioning hole 21g provided in the metal plate 21. . At the edge of the positioning hole 21g, three supporting pieces are formed so as to protrude inwardly, and a main scanning direction reference edge 2 is formed at the tip of each of these supporting pieces.
1a and the sub-scanning direction reference edges 21b and 21c,
The end face in the main scanning direction and the end face in the sub-scanning direction of the ceramic case of the CCD 2 are held in contact with each other.

Further, the main scanning direction reference 821a 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 row 2a of the CCD 2 is aligned with the predetermined position. Positioning is possible with an accuracy of 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, the CCD control board PCB-122, which includes an amplifying circuit for amplifying the image reading signal from the CCD 2, is connected to the CCD 2.
It is held by soldering to two connecting pins 2c.

There are two connectors 23 on the COD control board PCB-122.
are soldered, and flat cables 24 made up of a plurality of lead wires are each removably attached. C.C.
Mounting hole 22a provided on D control board PCB-122
A thermistor 25 for detecting the temperature of the CCD 2 is attached to the holder, and is held in contact with the ceramic case of the CCD 2 by adhesion with an epoxy resin.

Roughly, the CCD control board PCB-122 has 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 a drive control circuit for the CCD 2, and is larger than the CCD control board PCB-122 and is equipped with more control electronic components, so it also generates less heat. Therefore, it is desirable to install this CCD control board PCB-2400 as far away from C0D2 as possible. In this embodiment, the right support leg 100d and left support leg 100e extending downward from the base plate 100 are Against screw 404
By being locked by the COD control board PCB-1
The heat generated by the CCD 22 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 conceivable that electrical noise will be picked up through the flood cable 24, making it impossible to output an accurate signal corresponding to the original image. However, in this embodiment, as mentioned above, the CCD
The CCD control board PCB-122 directly connected to the CCD control board PCB-122 is provided with a read signal increase #i 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 also causes unnecessary force on the CCD2 even if the position of the C0D2 is adjusted over a relatively large range. 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 base 41 edge 21a and sub scanning direction reference edge 2
In addition to the reference edges 1b and 21c, three reference edges 21f in the optical axis direction are provided, and the cover glass 2b of the CCD 2 is positioned relative to these reference edges a21f in the optical axis direction. 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 CCD 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 socket 26, or the CC
The D control board PCB-122 can be replaced easily and inexpensively.

Next, the lens unit 300 will be explained with reference to FIGS. 13, 5, and 3. The lens holder 301 is made of aluminum casting in the shape of a broken circuit, and the rear part 301b of the lens holder 301 has three protrusions 301.
e 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. In other words, the axis of the hχ meeting hole 04 is precisely positioned 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 front 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 above-mentioned cylindrical female thread 95 is.

The circular female shaft 94 is locked to the front wall 80c of the rotating base plate 80. 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, a movable base plate 50 that holds the CCD base plate 221 and the movable base plate 50 is rotatably and slidably supported on the support shaft 64. Adjust the rotation so that the lower surface part 301d of the holder supports the support i1'1l164.
After the three screws 309 are set parallel to
It is adapted to be latched to the rotating base plate 80 at . This ensures the required perpendicular precision between the optical axis of the imaging lens 5 and the support shaft 64.

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 to have a diameter of 8 mm, and has a main shaft 3 of the focus adjustment shaft 306.
It is eccentric by 1.5+am with respect to the axis of 06C, and the length in the axial direction is set to be longer than the depth of the groove 322. The main focus adjustment axis 306 N 306 c has a diameter of 12
It is formed into a cylindrical shape, and has a conical portion 306d with an apex angle of 90° formed on the opposite side of the eccentric cam 306C, and this conical portion 306d is integrally connected to the auxiliary shaft 306f via a small diameter shaft 306e. is connected to. Auxiliary shaft 3
06f is formed to have the same diameter as the main shaft 306c, and a slotted portion 306g into which a driver can be fitted is formed on the end face of the auxiliary shaft 306f. 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. Component force P of the pressing force of the pressing rod 307 at the pressure contact point between these two
□ and P2 are directed in the axial direction and the direction orthogonal to the axis of the focus adjustment shaft 306, respectively, and the axial component force P
Due to the machining, the tip surface 306b of the eccentric cam 306a is formed into the groove 32.
As a result, the lens barrel 321 is pressed against the wall surface of the fitting hole 304 and maintained without play. In addition, the main shaft 30Ga and the auxiliary shaft 30G of the focus adjustment shaft 306 are pressed against the wall surface of the fitting hole 305 by the axis-perpendicular component force P2 and are maintained in a state without play, and the rotation of the focus adjustment shaft 306 is braked by the frictional force. It has become so. At this time, the groove bottom surface 32 formed by the end surface 306b of the eccentric cam 306a
2a, that is, the lens barrel 321 (7%,
The frictional force with the 9-hole 304 is based on the suppressing force from the set screw 308 against the pressure rod 307, but at least when the imaging lens 5 focuses the projected image on the CCD 2, the lens barrel 321 The pressing force from the set screw 308 against the pressurizing force 307 is adjusted to such an extent that the frictional force between the lens barrel 321 and the fitting hole 304 does not become greater than the pressing force exerted by the leaf spring 325 on the lens barrel 321.

To adjust the focus of the imaging lens 5, first, a driver is engaged with the slotted portion 306g and the focus adjustment shaft 306 is rotated. As a result, the eccentric cam 306a is eccentrically rotated, and the imaging lens 5 is moved in the optical axis direction.
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 temporary 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.

Focus! I! After l is completed, the set screw 308 is further screwed in to increase the above-mentioned axial component force P1 and axis-perpendicular component force P2, thereby ensuring that the imaging lens 5 is securely locked to the lens holder 301 without any displacement. At the same time, rotation of the focus adjustment shaft 306 is stopped.

Next, the position adjustment mechanism of the CG-D2 will be explained based on FIGS. 3, 4, 5, 12, 18, and 19.

First, in the tilt adjustment mechanism 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-adjustment mechanism around the Z-axis γ, which is the optical axis direction of the imaging lens 5.
As described above, the CCD unit 20 having the metal plate 21 that holds C0D2 at a constant reference position is mounted on two circular pedestals 31d formed on the upper surface of the channel 31 corresponding to the two reference mounting holes 21e. It is fixed by screwing in a screw pin 32. This allows CCD
2 can be easily replaced within a positional deviation range of 200 to 300 μm.

The COD control board PCB-122 is positioned so as to protrude downward from a rectangular mounting hole 31a formed in the channel 31.

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 in FIG. 12 in the X-axis direction of the movable base plate 50, a vertical shaft 35 is erected in the Z-axis direction (optical axis direction).
A cylindrical portion 35a formed at the upper end portion of this vertical shaft 35
The lower outer circumferential edge of is in contact with the conical inclined side surfaces of two conical portions 33a formed on the horizontal shaft 33. This results in channel 31 containing COD unit 2o.
The entire body is rotatable about 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 passes through a large diameter hole (not shown) formed in the channel 31 and projects downward, and its spherical tip portion 39a faces the upper surface of the movable base plate 50 having a U-shaped cross section. 50
It is in contact with i.

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 respectively screwed in the vicinity of the square rod 38, and the upper ends of tension springs 37a and 37/b are hung on these stepped pins 36a and 36b, respectively. The lower ends of the tension springs 37a and 37b are
They are hung on stepped pins 54a and 54b screwed onto the front wall 50g and rear wall 50h of the movable base plate 50, respectively. These tension springs 37a and 3
7b extends diagonally at an angle of about 45 degrees with respect to the Z axis (optical axis), and its tensile force causes 1) the channel 31 to be moved downward in FIG. And a rightward pressing force is generated.The rightward pressing force by the tension springs 37a and 37b causes the lower outer circumference 35a of the cylindrical portion of the vertical shaft 35 to be pushed against the horizontal axis. 2 formed in 33
The cylindrical portions 33 on both 1J side of the horizontal shaft 33 are pressed against the conical inclined side surfaces of the conical portions 33a at several locations, and are subjected to downward suppressing force by the tension springs 37a and 37b.
The lower surface of b is pressed against the upper surface 50d of the movable base plate 50. As a result, the entire channel 31 including the COD unit 20 is connected to the vertical axis 35 via the horizontal axis 33.
It is held in a three-point supported state by the movable base plate 50 and the movable base plate 50. Further, due to the downward suppressing force by the tension springs 37a and 37b, the spherical tip portion 39a of the adjustment screw 39 screwed onto the square rod 38 is pushed onto the movable base plate 5.
0 and is pressed against the upper surface 50i of 0. Therefore, by rotating the adjustment screw 39, the channel 3
1 is rotated and positioned around the Y axis, that is, in the α direction, about the horizontal axis 33.

At this time, the stepped pins 36a and 36b are connected to the horizontal axis 3.
3 and the adjustment screw 39, and the adjustment screw 39
, the lower surfaces of the cylindrical portions 33b at both ends of the horizontal shaft 33 are urged to be more strongly pressed against the upper surface 50a of the movable base plate 50, and the two are separated from each other. It is designed to be closely attached without any problems. Further, the urging force of the stepped pins 3Ga and 36b is set to such an extent that the channel 31 is not prevented from rotating around the vertical axis 35.

Furthermore, a twelfth channel in the X-axis direction of the channel 31
A spring hook portion 38g is formed protruding from the left end portion in the figure, and one end portion of the tension spring 40 is hung in a hole 31h provided in the spring hook portion 38g. On the other hand, a square bar 51 is screwed and fixed to the side surface of the movable base plate 50, and a stepped pin 52 is erected on the square bar 51.
The other end of the tension spring 40 is hung against the tension spring 40.

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 S3a 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 iA setting screw 53, the channel 3
1 is rotated about the vertical axis 35 around the Z axis, that is, downward, and is positioned.

The fine adjustment mechanism having such a configuration allows fine adjustment of the tilt 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 downward rotation around the Z-axis, which is the optical axis direction of the imaging lens 5. 1y1m is performed accurately. That is, first, by rotating the adjustment screw 39, the tension spring 3
The channel 31 is rotated about the horizontal axis 33 in opposition to the CCDs 7a and 37b, thereby positioning the CCD 2 in the α inclination direction. At this time, the center of rotation is U! F1'! Since the ii action position is separated from the ii action position, fine i adjustment can be performed without using a complicated mechanism such as a differential screw. 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 side wall surface 31s to the horizontal axis 33 is maintained at the required precision, the channel 31 is hardly rotated around the vertical axis 35 due to the above-mentioned sliding movement, and there is no problem in adjustment. do not have. Also, the horizontal axis 33
Since C0D2 is provided at a position sufficiently separated from CCD2, C0D2 is hardly displaced in the X-axis direction, which is the main scanning direction, when adjusting the CCD2 in the α tilt 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 C0D2 pixel column 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 5 of the movable base plate 50
The spherical tip portion 53a of the adjustment screw 39 is slid while being in contact with the top surface 50a of the movable base plate 5o, and the cylindrical portion 33b of the horizontal shaft 33 is being slid while being in contact with the upper surface 50a of the movable base plate 5o. However, since the surface angles of the upper surfaces 50i and 50a of the movable base plate 5o with respect to the vertical axis 35 are maintained at the required precision, the channel 31 is rotated around the horizontal axis 33 by the above sliding movement. There are almost no! Il! 1ff
There is no problem with i. In addition, since the vertical axis 35 is provided at a position sufficiently spaced from the CCD 2, the CCD 2 may be displaced in the X-axis direction, which is the main scanning direction, when adjusting the C0D2 in the γ direction around the Z-axis. rare.

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
Adjustment screw 5G for 5.57.

58 is sardine: young. The tip portions of the adjustment screws 56 and 58 are formed into a spherical shape, and the spherical tip portions are brought into contact with the front wall 80c of the rotating base plate 80.

On the other hand, the right side wall 50d of the movable base plate 5o in the X-axis direction
Fitting holes 50f are formed through the left side wall 50e, 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. Moreover, as especially shown in FIG. 4, the above-mentioned right side v! , 50d and the left side wall 50e are screwed to L-shaped plates 59 and 6o, respectively. Holes 59a and 60 formed at the tips of these L-shaped plates 59 and 60
One ends of tension springs 61a and 61b are attached to a. Further, as shown in FIGS. 3 and 4, a right lever 62 and a left lever 63 are rotatably mounted on the support shaft 64. Above right lever 62
Fitting holes 62a and 63a are formed in the left lever 63, and the supporting shaft 64 is fitted into these fitting holes 62a and 63a. The right lever 62 and the left lever 63 are on the right side of the movable base plate 5°.
d and the left side (1150e), and locking screws 68 and 6 are located in the elongated holes 62a and 63e formed in the upper arm parts 62d and 63d, respectively.
9 is engaged, the rotation of the right lever 62 and the left lever 63 with respect to the support shaft 64 is restrained. The locking screws 68 and 69 are threaded through the right side wall 80a and left side wall 80b of the rotating table plate 80 in the X-axis direction, respectively.

In addition, holes 62c and 63c are formed in the middle arm parts 62b and 63b extending in a direction perpendicular to the upper arm parts 62d and 63d, that is, toward the front wall 80c of the rotating base plate 8o. One ends of the aforementioned tension springs 61a and 61b are hung on 62c and 63c.

In the state shown in FIG. 4, the tension spring 61
a and 61b are placed in an energized state. The movable base plate 50 attempts to rotate in the fourth clockwise direction due to the biasing force of the tension springs 61a and 61b, but the spherical tip portions 5Ga and 58a of the adjustment screws 56.58 are pressed against the front wall 80c of the rotary base plate 80 It is designed to be stopped by being pressed against it. The tension spring 61a extends so that its biasing force generates component forces in the tangential and normal directions about the support shaft 64.

As a result, the movable base plate 5o is urged against the support shaft 64,
It 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 the lower arm portion 62f forms the right side wall 50d of the movable base plate 50.
is in contact with the lower edge of the

When the CCD unit 20 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, G2h and 63g, 63h are provided so as to face each other, and one of the circular arc holes 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 63h.

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 56 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 position are spaced apart from each other compared to the distance between the rotation center position and the CCD 2, minute y
Am can be performed. Note that this adjustment screw 56
, 58 is performed by rotational movement around the support shaft 64, but it is important to note that C0D2 is spaced apart from the support shaft 64 and that the position i
! Since the amount of movement for one adjustment is 1 to 2 m, C
The deviation in the inclination β direction of the CD2 in the sub-scanning direction is extremely small, so there is no problem. Also, when using a linear sensor with extremely small pixel dimensions (7 μm x 7 μm) as in this example, the pixel row The slight inclination β 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 other end portion of the side compression spring 65 is pressed and locked via a washer 66 to a pin 67 that is fixed so as to pass through the support shaft 64. I'm here.

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, an adjustment screw 83 is screwed into the right boss 81 so as to pass therethrough, and a spherical tip portion 83 of this adjustment screw 83 is fitted.
a is in contact with the right side wall 50d of the movable base plate 50.

The right side wall 50d of the movable base plate 50 is brought into pressure contact with the spherical tip portion 83a of the adjustment screw 83 by the force of movement of the movable base plate 50 by the compression spring 65. Therefore, by rotating the adjusting screw 83, the movable base plate 5
0 will be moved in the main scanning direction. The thread pitch of the adjustment screw 83 is set to 0.5+nm, and C
In order to satisfy the position iA alignment accuracy of 63.5 μm for the pixel row 2a of OD 2, it is only necessary to rotate the adjustment screw 83 with an accuracy of about 45°, making the adjustment operation extremely easy. ing. C due to this adjustment screw 83
In the main scanning direction (X-axis direction) adjustment operation of CD2,
There is no deviation in the position of the CCD 2 in the sub-scanning direction (Y-axis direction), the main-scanning tilt direction (α direction), the direction around the optical axis (γ direction), or the Z-axis direction. This means that the right angle between the support shaft 64 and the optical axis of the imaging lens 5 is ±1'.
In addition, the parallelism of the support shaft 64 to the exposure line 13 of the original image is also ±1'.
The movable base plate 50 is pressed in the radial direction of the support shaft 64 by the biasing forces of the tension springs 61a and 61b, and at the same time, the rotation of the rotary base plate 80 is maintained through the adjusting screws 56 and 58. This is because the position of the movable base plate 5o is maintained by the front surface u80c.

Further, as in this embodiment, the dimensions of the pixel row 2a of the CCD 2 (
35m), the support shaft 64 has sufficient spacing (180am)
Because they are arranged at a distance of Position of CCD2 in main scanning direction X! I! I! ! !
! The positional deviation in the sub-scanning direction (Y-axis direction) with respect to the quantity 2 is about 2 μm, and there is no problem in adjustment.

Next, the perpendicularity of the optical axis of the imaging lens 5 to the original exposure surface shown in FIG. 1, that is, the plane for reading the original 12 with the exposure line 13! :Explain the i mechanism.

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 rotating base plate 80 is arranged so as to face the front surface RIOOa of the base plate 100, which is formed in a U-shape in cross section.
The large diameter side of the conical shaft 94 passes through the circular arc hole portion 120a of the engagement hole 120 (see FIG. 5(b)) provided in the front wall 100a of the base plate 100, and It projects inside the plate 100. At this time, the circular arc hole portion 120a of the engagement hole 120 is formed to be smaller than the maximum diameter of the conical portion of the one conical shaft 94 and larger than the minimum diameter, so that the conical inclined surface 94a of the conical shaft 94 engages. It is engaged with the circular arc hole portion 120a of the mating hole 120. As a result, the rotating base plate 8
0 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 adjustment 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 base plate 80. 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 91 are erected on the left side wall 80b of the rotating base plate 80, and tension springs 92 are installed between the stepped pins 93 and the stepped pins 91. is spread across the board. As a result, the base plate 10
The rotary base plate 80 is urged to rotate counterclockwise around the conical shaft 94 with respect to the front surface u l OOa of 0, and is welded to the right side wall 80a of the rotary base plate 8o. The upper surface 90a of the square rod 90 is pressed against the spherical tip portion 102a of the adjusting screw 102, so that the rotating base plate 80 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 gxooa of 00, three circular pedestals 100f are formed on the circumference centered on the conical axis 94 at an even pitch of approximately 120°, and these circular pedestals 100
The outer surface of the front wall 80'C of the rotating base plate 80 is brought into contact with the upper surface f, and the rotating base plate 8o is supported at three points, so that the rotating base plate 80 can be rotated stably. It has become. 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 one conical axis 94. Long hole 84
, 85, 86 are screwed into the front wall 100a of the base plate 100 to fix the rotating base plate.

Therefore, if the adjusting screw 102 is rotated with the set screws 86, 87, and 88 loosened, the rotating base plate 8o is rotated about the conical shaft 94, and the surface angle of the optical axis of the imaging lens 5 is rotated. will be adjusted.

In the perpendicularity adjustment operation of the optical axis using the adjustment screw 102, the position of the CCD 2 is adjusted in 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. Moreover, the three-point support structure of the rotating base plate 80 prevents the rotating base plate 80 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 216 so that the right main shaft 215 and the upper right shaft 217 are 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 upper left 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 upper left 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 portion of the left support plate 218, and the bottom surface 2 of this recess 218a
A bearing portion 218b having an arcuate cross section is recessed in the center portion of 18f. The left main shaft 2 is attached to this bearing portion 218b.
15 are fitted.

In addition, the right main shaft 21 is located on the bottom surface 218f of the recess 218a.
A square bar 219 for positioning 5 is fixed by two setscrews 220. -Groove 21 in the force destination 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 immovable in the left and right main axis direction, that is, in the main scanning direction (X-axis direction). Location is now restricted.

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

Further, the shaft 214 is accommodated in the upper end portion and the lower end portion of the left support plate 218 in a loosely fitted state.
18 c and 218 d are recessed, and the shaft 21
Adjustment screws 222 and 223 are screwed into the upper and lower end portions of the left support plate 218, respectively, so as to press the left support plate 218. By rotating the adjusting screws 222 and 223, the left support plate 218 is rotated about the biaxial shaft.

Further, a bearing portion 225a having an arcuate cross section is recessed in the center portion of the right support plate 225.
The upper right shaft 217 is fitted into the upper right shaft 217 . Also, the right support plate 22
5 has a square rod 22 for positioning the upper right 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 image forming 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 adjustment screws 222 and 223 are rotated.

The optical axis of the imaging lens 5 is rotated integrally with the base 200,
The inclination in the sub-scanning direction (Y-axis direction) will be finely adjusted. As a result, the perpendicular liquid between the optical axis of the imaging lens 5 and the yX document exposure surface in the sub-scanning direction is finely adjusted. In such an adjustment operation, the imaging lens 5
No deviation occurs 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 pressure screw 2
21 and 228 and adjustment screws 222 and 223, the base 200 is fixed in position, and therefore the position of the imaging lens 5 is fixed.

Next, the lens unit 300 and the COD unit 20
Adjustment of movement in the optical axis direction of the lens! I will talk about one mechanism.

Next, the lens unit 300 and the CCD unit 20
The mechanism for adjusting the movement of the lens in the optical axis direction will be described below.

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.
Upper left axis 215 and upper right axis 2 parallel to and coaxial with 3
This base 20 is rotatably supported by a base 17.
Fitting holes 201 and 202 are formed in the upper side u200b and lower side wall 200c of 0, respectively, so as to face each other. These fitting holes 201 and 202 have an upper left shaft 23.
1 and the upper right axis 217 at right angles to both axes.
13 is inserted. On the other hand, the upper wall 1 of the base plate 100
00b and the lower wall 100c have the above-mentioned fitting holes 201.
, 202 are formed with elongated holes 111 and 112 extending in the sub-scanning direction, 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 100 of the support shaft 113
Retaining rings 114 are respectively locked on the upper and lower sides of the upper wall 100b and the lower wall 1OOC, so that the support shaft 113 along with the base plate 100 is
It is supported so that it can slide in the optical axis direction. At this time, the base plate 100 is movable in the sub-scanning direction (Y-axis direction) and remains stationary in the main-scanning direction (X-axis direction), so that it moves f.

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 the upper right 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, in the front wall 100a of the base plate 100, there are three vertically long elongated holes 103 at positions corresponding to the three circular pedestals 203.
The screws 104 pass through each of these elongated holes 103. A compression spring 106 is attached to the outside of the screw 104, and this compression spring 10G
A tube 105 is attached to the outside of the tube. compression spring 106
One end portion is pressed against the screw head of the screw 104 through a washer 107, and the other end portion of the compression spring 106 is pressed against the base plate 100 through a washer 108. As a result, the white plate 100 is pressed toward the circular pedestal 203, and the base plate 100 is pressed against the circular pedestal 203 by the urging force of the three compression springs 106, and the lens is moved along the support shaft 113. It is made slidable in the direction of the optical axis. At this time, the base plate 100 remains stationary in the sub-scanning direction.

Further, a square rod 109 is screwed to the right end of the upper wall 100b of the base plate 100 near the support shaft 113, and an adjustment screw 110 is screwed to pass through the square rod 109. Spherical tip portion 11 of the adjustment screw 110
0a passes through a large diameter hole (not shown) formed in the base plate 10 and abuts on the upper wall 200b of the base 200.

In this embodiment, a base plate 100, a rotating base plate 80 attached thereto, and a lens unit 300 attached to the rotating base plate 80.

Due to the weight of the CCD unit 1-20, CCD base plate 22 1-30, support shaft 64, etc., the stand t) 2100 is moved to the support shaft 11.
3 is configured such that the SWX low drag and low mountain force between the front wall 100a of the base plate 100 and the front surface 203a of the circular base 203 is increased by the compression of the three compression springs 106. Therefore, no spring is used to press and bias the base plate 100 downward. However, if necessary, for example, the lower side q 100 c of the base plate 100 and the base 2
A compression spring may be inserted between the support shaft 113 and the lower wall 200c of the support shaft 113.

In such a configuration, by rotating the thirteen adjustment screws 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. As a result, the distance urJ between the exposure line 13 and C0D2, that is, the conjugate length (L in FIG. 2) at a predetermined projection magnification, can be easily and accurately fine-tuned. Moreover, during such adjustment, the imaging lens 5 and CCD 2 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, we will explain the four types of light shielding and dustproof seals of C0D2.

3 and 5, a seal body 31 is attached to the lower part 301d of the lens holder 301 of the lens unit 300.
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 2o 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 C0D 2.

The sealing body 310 is formed into a rectangular tube shape of a soft foamed resin having light-shielding and breathable properties with a fine opening, and its elastic force allows the lens holder 301 and the metal plate 2
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, the CCD 2
External light that would degrade the image reading capacity of the CCD 2 is blocked, and the adhesion of dirt, dust, etc. to the CCD 2 is also prevented.

Further, the seal body 310 is formed of a material and shape that does not impair air permeability, and is designed to sufficiently prevent interference and deterioration of the image reading function of the C0D2. 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 such an extent that it is possible to separate 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 forced by the blower 206 is filtered to remove dirt, dust, and other dust by the dust filter 208 attached to the duct 1-207. , flows into the base 200 from the square hole 205 of the base 200 to the square hole 100 of the base plate 100.
g and the square hole 80e of the rotating base plate 80, the seal body 310, the lower part of the CCD2 (7) and the PCl3-122
It is designed so that it can be sprayed towards. The blowing action of the blower 206 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 CCD unit 1-20,
Expansion and deformation of the CCD2 due to heat generation from the C0D2 itself or the PCB-122 soldered to the CcD2 should be prevented. This will prevent image reading abnormalities from occurring, and the electrons on the r'cI3-122. Malfunctions due to heat generated by parts are also prevented.

Although the CCD 2 installed in the document reading device is designed to prevent dirt and dust from adhering to the surface of the cover glass 2b, normal reading may be hindered during long-term use. J! ! Since dust may adhere to it, 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. In addition, when simply cleaning the CCD 2 without replacing it, the CCD unit 20 is configured to expose the CCD unit 20 at an angle to the front, thereby making the cleaning operation extremely easy. In addition, the position of the CCD 2 mounting member is set to 4S so that it can be accurately returned to its original position by the adjustment screw and spring bias even when the CCD unit 20 is replaced, as well as during cleaning. The structure is such that fine adjustments due to dimensional variations in the angle 2o 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 rotating base plate 80 is connected to the upper arm 62d of the right lever 62. When the right lever 62 is retracted to the position where it is removed from the elongated hole 62e, the right lever 62 is rotated around the support shaft 64 in the sixth figure by the biasing force of the tension spring 61a. The bent portion of the lower arm portion 62f of the right lever 62 is brought into contact with the lower edge portion of the movable base plate 50 on the right side <1150 d. As a result, the relative positions of the movable base plate 5o and the right lever 62 around the support shaft 64 are stabilized. Similarly, the screw 69 screwed into the left side wall 80b is connected to the left lever 6.
3, the bent portion of the lower arm 63f of the left lever 63 comes into contact with the lower edge of the left side 'l 50 Q of the movable base plate 5o. 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 with the D unit 20 attached has a right lever,
62, can be rotated integrally with the left lever 63 to the outside of the projection optical path of the imaging lens 5, but the range of rotation is limited to the screws 73 screwed into the right boss 81 and the left boss 82, respectively. and 74, the circular arc hole 6 of the right lever 62
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 20 is exposed at the front of the apparatus, and cleaning of the CCD 2, replacement, and attachment/detachment of the CCD unit 20 are extremely easy. In addition, in this state, the arcuate hole 62g of the right lever 62 does not come into contact with the adjustment screw 83 that cooperates with the compression spring 65 to position the movable base plate 50 on which the CCD unit 20 is attached in the main scanning direction. The position and size of the arcuate hole 62g are set so as to prevent the adjustment screw 83 from being displaced or deformed due to excessive force being applied to it. . At this time, the movable base plate 5
The holding member (channel 31 in FIG. 3) of the CCD unit 2o, 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 the CCD unit 2o, 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 50d 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. The position adjustment allowance on the left is also used to adjust the position of the CCD2, using the steps of the screw. That is, in this embodiment, means for suppressing the male thread and the female thread in the radial direction is used 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 38 and the movable base plate 50 are biased 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 the adjusting 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. Further, a female thread 73 is formed in a direction perpendicular to the screw axis of the female thread 38a formed at the corner 4//138, and has a diameter equal to or slightly smaller than the root diameter of this female thread 73, and A cylindrical brake 71 made of nylon and having a length approximately equal to the root diameter of the female thread 73 is fitted into the female thread 73. Also, the above female thread 73
A set screw 72 is screwed inside from behind the brake element 71, and a planar tip 72a of the set screw 72 suppresses the brake element 71t.

The planar tip 72a of the set screw 72 is connected to the brake member 71.
When the set screw 72 is screwed in more strongly from the state in which it is in contact with the nylon brake element 71, the tip part of the nylon brake 71 is pressed against the adjustment screw 39 while being compressed and deformed, and the tip part 71a of the brake element 71 is pressed against the adjustment screw 39. 39, and the peripheral surface 71b of this brake 71 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 yAffi screw 39 presses the female thread 38a in the radial direction, and the axial center of the adjustment screw 39 is maintained at a slight angle from the axial center of the female thread 38,1.
The adjustment screw 39 is rotated without shifting its axial center position due to the rotation of the inner body. Therefore, the tip 3 of the adjusting screw 39
9a is not moved in the radial direction of the screw. When rotating the adjusting screw 39 having a male thread that engages with the female thread 38a, the relative position between the square bar 38 and the movable base plate 50 is adjusted by the steps of the adjusting screw 39. The abutment position of the tip end 39a of the adjusting screw 39 against the upper surface 50i of the movable base plate 50 is prevented from shifting due to play in the engagement between the adjusting screw 39 and the female screw 38a.

Furthermore, when the nylon brake 71 is plastically deformed as described above, elastic stress is generated in 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 configuration, after the relative position between the movable base plate 50 and the square bar 38 is adjusted by moving the adjusting screw 39 back and forth, the set screw 72 is further screwed in, thereby further suppressing and deforming the brake element 71. Adjustment screw 39 is female thread 38
It is immovably locked with respect to a. In this case, the adjustment screw 39 will not be displaced from the female thread 38a by screwing in the set screw 72. Therefore, no other fastening means is required for locking the adjustment screw 39 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 power of oppression. By doing this, the 1m screw 39 is rotated with its axial center position maintained at a predetermined position by the required pressing force, and there is no damage to the threaded portion of the adjustment screw 39. Also, no indentation is caused, and therefore the smooth rotation of the adjusting screw 39 is not hindered in any way.

The position adjustment device constituted by the adjustment screw 39, the square bar 38, the upper surface 50i of the movable base plate 50, the brake 71, and the set screw 72 is similar to other position adjustment devices, that is, the adjustment screws 53, 56, and 58°. The same method is adopted in a position adjustment device using 102.110.83.

[Effects of the Invention] As described above, the present invention can reduce the influence of electrical noise picked up by the flat cable, and allows the photoelectric conversion element and the printed circuit board to be installed separately in good condition. can do.

[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, Fig. 2 is an external perspective view showing the positional relationship between the 1ffi imaging lens and the CCD, and Fig. 3 is a front explanatory view showing one set of CCD reading units;
Figure 5 (Q) shows the CCD shown in Figure 1.
5(b) is a front explanatory view showing the shape of the hole provided in the base plate; FIG. 7 is a plan view showing the positioning and fixing structure of the CCD, and FIG. 8 is taken along line A-A' in FIG. 7.
9 is a plan view showing another embodiment of the CCD positioning and fixing structure, and FIG.
A cross-sectional explanatory diagram along the B-B' gland in the figure, Figure 11 is CC
An explanatory cross-sectional view equivalent to FIG. 10 showing another example of the contact structure of D, FIG. 12 is an exploded perspective view showing the fine adjustment structure of COD, and FIG. 13 is a focus adjustment of the imaging lens. 14 is a front view showing the reading unit shown in FIG. 3 removed from the base, and FIG. 15 is taken along line AA' in FIG. 14. A cross-sectional explanatory diagram along the line, Fig. 16 is B-B in Fig. 14.
FIGS. 17 and 18 are cross-sectional explanatory views taken along line 1 and 2, respectively, and are cross-sectional explanatory views showing the locking structure of the adjustment screw. 1.2.3...CCD, 4,5. G...Imaging lens, 12...Document, 13...Exposure line, 15...Reading unit h, 20...CCD unit, 21...Metal plate, 22...First printed circuit board , 24... flat cable, 400... first printed circuit board. (1 idiot) Eroq figure low β? Ff) 40 mouths Jl? Iσ shape 40 circles Je diagram

Claims (1)

[Claims] An image in which a document image is projected onto a photoelectric conversion element by an imaging lens, and the document image is read photoelectrically by moving the document image and the photoelectric conversion element relative to each other in the sub-scanning direction. In the position adjustment mechanism of the reading device, the photoelectric conversion element holds a first printed circuit board having a function of amplifying and outputting a read signal by the photoelectric conversion element, and a second printed circuit board having a circuit for electrically controlling the photoelectric conversion element. A position adjustment mechanism for an image reading device, characterized in that a printed circuit board and the first printed circuit board are connected by a flexible cable.