JPH0118407B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slit exposure apparatus.

The scope of application of the present invention includes a slit exposure type copying machine and its application equipment.

First, regarding the slit exposure method that is closely related to the present invention, we will introduce the technology already proposed by the present inventor, and then describe the present invention.

In FIG. 1, reference numeral 1 is a contact glass that extends in the direction penetrating the plane of the paper, reference numeral 2 is a belt-shaped photoreceptor placed parallel to and opposite to the contact glass 1, and reference numeral 3 is a contact glass placed on the contact glass 1. Reference numeral 4 indicates an optical system having a function of forming an image of the original 3 on the photoreceptor 2 with a predetermined slit width.

In such a configuration, there are two methods for slit exposure of the original image onto the photoreceptor.

One method is to expose an optical system in a stationary state while synchronizing the contact glass 1 and photoreceptor 2 while moving in a constant scanning direction, for example, in the direction of arrow A. This is a method in which only the optical system 4 is moved in a constant scanning direction, for example, in the direction of arrow B, to expose the contact glass and the photoreceptor 2 which are placed in a stationary state.

Comparing the above two methods, we find that in the former method, it is technically difficult to synchronize the moving speed of the contact glass 1 and the moving speed of the photoreceptor 2, so it is difficult to obtain high-quality images. I can't.

On the other hand, in the latter method, the contact glass 1 and the photoreceptor 2 remain stationary, and only the optical system moves, so there is no problem of image quality deterioration due to synchronization difference between the contact glass 1 and the photoreceptor 2. .

For this reason, several slit exposure methods employing the latter method have been proposed.

As one of them, the configuration shown in FIG. 2 is an embodiment of the slit exposure apparatus previously proposed by the present inventor. A roller serving as a first insulator, which is a part of a movable table 7, is configured by attaching an imaging optical system 4 to an endless belt-like (or belt-like) photoreceptor 2 that is tensionably supported by a roller. 8, and while the photoreceptor 2 at this pressure contact portion is pressed down (or pushed up) and supported by the first pressure contact compared to the non-pressure contact state, the movable stage 7 is moved against the photoreceptor 2 in a stationary state. is moved along a guide member (not shown) in a constant scanning direction indicated by arrow C, and the contact glass 1, which is fixedly set along the constant scanning direction, is pressed against the photoreceptor by the roller 8. The document is scanned while controlling the distance between the image forming optical system 4 and the contact glass 1, and the distance between the image forming optical system 4 and the contact glass 1, and from the image forming optical system 4 to the pressure contact portion with desired precision within a predetermined scanning range. This is called a slit exposure device. In the figure, reference numeral 9 indicates an exposure lamp that irradiates the surface of the document, and is provided integrally with the movable table 7. Further, a compressible spring indicated by reference numeral 10 is stretched between the roller 6 and the immovable member, and constantly applies an appropriate tension to the photoreceptor 2.

By the way, in the slit exposure apparatus having the configuration shown in FIG. 2, after the imaging optical system scans the document surface,
When returning to the home position, the scanning speed is often set to be less than the return speed in order to increase the copying speed. However, in this case, there is a particular problem in that the contact between the first pressure contact and the photoreceptor during return causes the photoreceptor to generate heat, wear out due to rubbing, and accelerate the degree of deterioration.

SUMMARY OF THE INVENTION An object of the present invention is to provide a slit exposure apparatus that can solve the above problems.

In order to achieve the above object, the present invention is provided in a moving body configured by mounting an imaging optical system on a belt-shaped or endless belt-shaped photoreceptor that is tensionably supported between at least two positions. A control means is provided for selectively controlling the first pressure contact to be brought into pressure contact or to a non-pressure contact state, and the control means causes the photoreceptor in the pressure contact portion to be pushed up by the first pressure contact compared to the non-pressure contact state. When scanning a document, the movable body is moved forward along the document table in the push-up state or in the push-down state, and when the document is not scanned, the movable body is moved forward along the document mounting table. Separating the pressure contact from the photoreceptor,
During the forward movement, the imaging optical system and the first insulator are placed on a straight line, and the photoreceptor and the document mounting table are set in a relationship perpendicular to the straight line. It is something.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that in the following explanatory diagrams, in order to avoid complexity, the same reference numerals as in FIGS. 1 and 2 are used for parts that are unlikely to be confused.

In order to avoid the drawbacks of the prior art, it is sufficient to break the contact between the first pressure contact and the photoreceptor and to separate them at the time of return. Hereinafter, some embodiments of this separation means will be introduced.

(1) First embodiment (see Figures 3 to 6).

Referring to Figure 3, when scanning the original for exposure,
The imaging optical system 4 and the roller 8 as a first pressure contact move together with a moving table (not shown) in the scanning direction indicated by the arrow C to scan the document. When one part of the movable table presses the return switch 11 provided at the end of the scanning range to turn on, only the roller 8 part is turned on by the control means (mechanism to be described later) along with a return command as shown in FIG. is moved downward, and the photoreceptor 2 and the roller 8 are separated from each other during the return movement in the return direction indicated by the arrow D. Then, when the home position is reached and a part of the movable table presses the home position switch 12, the roller 8 moves in the direction to come into pressure contact with the photoreceptor 2 again, returning to the state at the time of the initial document scanning.

Therefore, the photoreceptor 2 and the roller 8 do not come into contact during the return, and the object of the present invention can therefore be achieved.

Next, an example of a control means for moving the roller 8 away from the photoreceptor or returning it to contact with the photoreceptor will be described with reference to FIG.

In FIG. 5, one end portions of arms 13 and 14 are pivotally supported on both sides of the arch-shaped movable table 7, respectively. Below is the peripheral part of arm 13 and arm 14
Since the peripheral portions of the arms 13 and 13 have the same configuration, the description of the configuration around the arm 14 will be omitted, and the peripheral portion of the arm 13 will be described.

Now, as described above, one end of the arm 13 is pivotally supported on the movable table 7 by the screw 15. A stay 16 is connected between the other end of the arm 13 and the arm 14.
The arms 13 and 14 are stretched across and fixed.
The interval is kept constant.

Next, directly below the imaging optical system 4 fixed to the movable table 7, a roller 8 as a first pressure contact is mounted on the arm 1.
It is pivoted so that it spans between 3 and 14.
A pin 17 is installed on the arm 13 between the pivot portion of the roller 8 and the screw 15, and a pin 17 is installed on the side surface of the moving table above the pin 17.
8 is implanted, and a tension spring 19 is applied between each of the pins 17 and 18, so that the arm 13 is constantly subjected to a force in a counterclockwise direction with the screw 15 as a fulcrum. There is. The rotation due to this force is caused by the stopper 2 installed in the movable table 7.
Blocked by 0.

A pin 21 is implanted on the arm 13 between the pin 17 and the screw 15, and this pin 21 is attached to the arm 23 whose one end is connected to the plunger 22 of the solenoid SOL fixed to the side wall of the moving table 7. The other end is pivotally supported.

Now, as shown in FIG. 5, when the arm 13 is in contact with the stopper 20, the photoreceptor 2 is in pressure contact with the roller 8, and the relationship between the roller 8 and the photoreceptor 2 is It is assumed that the configuration is as shown in FIG. The document is scanned in this state, and when a portion of the moving table 7 eventually presses the return switch 11, the solenoid SOL is energized by the signal and the plunger 22 is pulled, resisting the force of the spring 19. arm 13
rotates clockwise around the screw 15, and along with this rotation, the roller 8 is lowered. Then, the photoreceptor 2 and roller 8 are separated. In this separated state, the moving table 7 enters the return operation, and when a part of the moving table 7 presses the home position switch 12, the return operation stops, and at the same time the solenoid
The excitation of SOL is released and the arm 13 is moved to the stopper 2.
The roller 8 rotates until it hits 0, and the arm 13
At the same time, it is moved upward and returns to the original scanning position. Thus, the control means in this example is the arm 1
3, 14 and solenoid SOL as the main members.

FIG. 6 shows an example in which the first pressure contact is composed of a rectangular sliding plate 50 instead of the roller 8. In this case, the exposure area can be widened, but the contact area with the photoreceptor is also large, so The effects of the present invention are significant.

(2) Second embodiment (see Figures 7 and 8).

A roller 6 at the end of the scanning stroke that supports the photoreceptor 2
is pivotally supported on the arm 24, while the arm 24
The center portion of the arm 24 is pivotally supported to a stationary member by a pin 25, and the end portion of the arm 24 is pivotally connected to a plunger 26 of a solenoid SOL. A compressible spring 27 is hung between the pin 25 and the pivot portion of the roller 6 on the arm 24.
A force is applied to rotate the pin 25 in a counterclockwise direction around the pin 25. The rotation of the arm 24 due to this force is caused by a pin 24 implanted in the immovable member.
This is prevented by the side part of the arm 24 abutting against the side part of the arm 24. This is the state shown in FIG. 7 during document scanning. Note that a roller indicated by the reference numeral 29 is provided together with a spring 30 in order to constantly apply an appropriate tension to the photoreceptor 2.

Now, when exposing and scanning a document, the imaging optical system 4 and the roller 8 as the first pressure contact move together with a moving table (not shown) in the scanning direction shown by arrow C to scan the document. However, at the end of this scanning, when a part of the moving platform presses and turns on the return switch 11 provided at the end of the scanning range, the eighth switch is turned on.
As shown in the figure, the solenoid SOL is energized, the plunger 26 is pulled, the arm 24 is rotated clockwise about the pin 25, and the roller 6 is lifted upward, so that the photoreceptor 2 is also It moves upward, and the photoreceptor 2 and roller 8 are separated. In this way, the return operation is started, the moving table reaches the home position position, and when the home position switch 12 is pressed, the excitation to the solenoid SOL is released, the roller 6 is lowered by the tension force of the spring 27, and the photoreceptor 2 is also moved to the roller 8 position. 7, and returns to the document scanning state shown in FIG. Thus, the control means in this example is constructed using the arm 24 and the solenoid SOL as main members.

(3) Third embodiment (see Figures 9 to 12).

Referring to FIG. 9, when scanning the original for exposure,
The imaging optical system 4 and the roller 8 as a first pressure contact move together with a moving table (not shown) in the scanning direction indicated by the arrow C to scan the document. When a part of the movable table presses the return switch 11 provided at the end of the scanning range to turn on, as shown in FIG. 10 along with a return command, the movable table and the imaging optical The entire unit, including the system, first pressure contact, etc., is moved downward. As a result, the photoreceptor 2 and roller 8 are separated from each other at the time of return. Then, when the home position is reached and a part of the movable table presses the home position switch 12, the roller 8 moves in the direction to come into pressure contact with the photoreceptor 2 again, returning to the state at the time of the initial document scanning.

Next, an example of a control means for moving the roller 8 away from the photoreceptor or returning it to contact with the photoreceptor will be described with reference to FIGS. 11 and 12.

In FIG. 11, one end of a movable table 31 having a substantially T-shaped side surface is slidably penetrated by a guide bar 32 provided along the scanning direction. On the other hand, a roller 33 is pivotally supported at the other end of the movable table 31, and this roller 33 is placed so as to roll on another guide bar 34 provided parallel to the guide bar 32. Further, an imaging optical system 4 is attached to the moving table 31, and a roller 8 pivotally supported by an arm 35 provided on the moving table 31 is located directly below the imaging optical system 4. are doing. A stay 36 is hung over the ends of the guide bars 32 and 34 to stop them, and the other end of each guide bar 32 and 34 is connected to the first end.
As shown in FIG. 2, a conical recess 37 is formed, and a conical fulcrum member 3 is inserted into this recess 37.
The tip of 8 is pressed against it. It is assumed that the tip angle of the fulcrum member 38 is machined to be smaller than the conical angle of the recess 37, and the fulcrum member 38 is fixed to a stationary member. Therefore, stay 3
If you move 6 upward or downward, guide bar 3
2 can be rotated using the tip of the fulcrum member 38 as a fulcrum, and the unit consisting of the moving table 31, the imaging optical system 4, the roller 8, etc. can also be moved upward or downward.

A pin 39 is implanted in approximately the center of the stay 36, and the other end of a connecting rod 41, one end of which is pivotally supported by a plunger 40 of the solenoid SOL, is pivotally supported on this pin 39. Also, pin 39
One end of a tight spring 42 is hung on the
The stay 36 is constantly pulled upward by this spring 42. And the guide bar 3 by the spring 42
The rotation of 2 is caused by the stopper 4 implanted in the immovable member.
This is prevented by the guide bar 32 abutting against the guide bar 3.

Now, as shown in FIG. 11, when the guide bar 32 is in contact with the stopper 43, the photoreceptor 2 is in pressure contact with the roller 8, and the relationship between the roller 8 and the photoreceptor 2 is It is assumed that the configuration is as shown in FIG.

The document is scanned in this state, and when a portion of the moving table 31 presses the return switch 11, the solenoid SOL is energized by the signal and the plunger 40 is pulled, resisting the force of the spring 42. The guide bar 32 (the same applies to the guide bar 34) rotates clockwise around the tip of the fulcrum member 38, and along with this rotation, the movable table 31, the imaging optical system 4, the roller 8, etc. The entire unit is lowered. Then, the photoreceptor 2 and roller 8
and are separated.

In this separated state, the moving table 31 enters the return operation, and when a part of the moving table 31 presses the home position switch 12, the return operation stops, and at the same time, the solenoid SOL is de-energized and the guide bar 32 is moved to the stopper 43. The roller 8 rotates until it reaches the end, and the roller 8 also returns to the original scanning position. Thus, the control means in this example is composed of the guide bars 32, 34, the stay 36, the support member 38, and the solenoid SOL as main members.

As described above, according to the present invention, the contact time of the first pressure contact with the photoreceptor is greatly reduced, which is advantageous in that the life of the photoreceptor can be extended.

[Brief explanation of drawings]

Fig. 1 is a general explanatory diagram of the slit exposure method, Fig. 2 is a front view of the vicinity of the imaging optical system illustrating the slit exposure method as a prior art related to the present invention, and Fig. 3
4 is a principle diagram explaining the first embodiment of the present invention, and FIG. 5 is a principle diagram explaining the first embodiment of the present invention.
FIG. 6 is a perspective view of the first insulator composed of a sliding plate, and FIGS. 7 and 8 are views of the area around the imaging optical system for explaining the second embodiment of the present invention. A front view, FIGS. 9 and 10 are principle diagrams explaining the third embodiment of the present invention, FIG. 11 is a perspective view of the vicinity of the imaging optical system explaining the third embodiment of the present invention, and FIG. 12 is a front view of the end of the guide bar. 1...Contact glass, 2...Photoreceptor, 4...
...Imaging optical system, 7, 31... Moving table, 8... Roller (as a first pressure contact), 11... Return switch, 50... Sliding plate (as a first pressure contact), 13, 14, 24... Arm, 32, 34...
...Guide bar, 36...Stay, 38...Support member, SOL...Solenoid.

Claims (1)

[Claims] 1. Pressing a first insulator provided on a moving body equipped with an imaging optical system against a belt-shaped or endless belt-shaped photoreceptor that is tensionably supported between at least two positions; Alternatively, the control means selectively controls the non-pressure contact state, and the control means pushes the photoreceptor of the pressure contact part up by the first pressure contact compared to the non-pressure contact state, or separates the photoreceptor into the non-pressure contact state. When scanning a document, the movable body is moved forward along the document table in the push-up state or the push-down state, and during backward movement when the document is not scanned, the first pressure contact is moved against the photoreceptor. A slit exposure device that is separated from the
During the forward movement, the imaging optical system and the first pressure contact are on a straight line, and the photoreceptor and the document mounting table are each set to be orthogonal to the straight line. Slit exposure equipment.