JPH075479Y2 - Exposure device in image forming apparatus - Google Patents

Description

The present invention relates to an exposure device in an image forming apparatus such as a copying machine, and more particularly to a reflecting mirror support structure.

(Prior Art) As is well known, in a copying machine, which is one of image forming apparatuses, there are cases in which the size of a document image is changed and a so-called enlarged or reduced image is copied. The position of a reflecting mirror (hereinafter referred to as a mirror), which is an optical member used in the exposure scanning system, or a lens is changed.

That is, FIG. 13 shows the overall structure of a copying machine provided with the above-described exposure scanning system. In this copying machine 1, a belt-shaped photosensitive member 2 which is movable in the direction of the arrow in the drawing is arranged. ing.

Around the photoconductor 2, a charging device 3, an exposure device 4, a developing device 5, and a transfer / separation device 6 for executing a copying process are arranged along the moving direction, and transfer in the moving direction is performed. A cleaning device 7 is provided behind the separating device 6, a fixing device 8 and a paper discharging device 9 are provided in the vicinity of the transferring / separating device 6, and in front of a confluence position with the transferring / separating device 6, The sheet feeding devices 10 are arranged respectively.

The above-described exposure device 4 includes a light source lamp 4A and a reflecting mirror which are located in the vicinity of the original placing table 1A provided on the upper portion of the copying machine body.
4B, a first mirror 4C for introducing reflected light from the document table 1A into the photoconductor 1, a lens 4D, and a second mirror 4E.

In this exposure apparatus 4, the amount of movement (ΔL) of the optical member required at the time of zooming is represented by ΔL≈ (1-1 / m) f ... where f: lens focal length and m: magnification FIG. 14 shows a graph of this movement amount.

FIG. 14 shows the amount of vertical movement within the main body of the copying machine with the vertical axis as the reference (the position indicated by “0” in the figure) at the same size, and the horizontal axis shows the magnification. There is.

In FIG. 14, the amount shown by the chain double-dashed line A is the result obtained from the above-mentioned formula, and from this result, at the time of reduction / magnification,
A large change in movement amount is required.

Therefore, in view of such an actual situation, the movement of the optical member is
If it is performed only for the first mirror 4c, it will be located further below the position of the first mirror 4c at the time of reduction shown by the chain double-dashed line in FIG. 13, and will approach the photoconductor 2. There are restrictions on the locations of the charging device 3 and the cleaning device 7. Therefore, in order to eliminate such a problem, the original placing table 1A
It is necessary to raise the position of the above position to move away from the photoconductor 2, and as a result, the height of the main body of the copying machine becomes high, which causes a problem in operability when setting a document.

Further, instead of such movement of the first mirror 4C, a lens
When trying to set the optical path length for zooming by moving only 4D, it is necessary to move further to the left side of the lens position at the time of reduction shown by the chain double-dashed line in FIG. 13, and as a result, By approaching the second mirror 4E, there is a possibility that part of the projected image will not fit inside the second mirror 4E and may be chipped. Therefore, in order to eliminate such a problem, the position of the second mirror 4E in the main body of the copying machine is
It is necessary to secure a space for moving the projection image to a position where the projected image does not drop in accordance with the movement of the lens, which increases the horizontal size of the copying machine main body and causes the copying machine to increase in size. A new problem will arise.

Therefore, for the purpose of solving such a problem, a structure has been proposed in which the first mirror and the second mirror are made to cooperate with each other so as to obtain a stroke smaller than a movement stroke in the case where the two move independently. There is.

(Problems to be solved by the invention) By the way, in the structure of the optical system as described above, the position first mirror 4C and the second mirror 4E are fixed to a movable supporting unit in the optical path, so-called In many cases, the mirror was integrated with the unit during the assembly process so that the mirror could not be removed after once fixed. Therefore, there is a possibility that a new problem may occur that the mirror cannot be replaced or removed for cleaning.

Further, in such a structure, when the mirror is loaded in the supporting unit, when the supporting unit has, for example, a box shape capable of exposing the reflecting surface excluding the reflecting surface of the mirror, When the mirror is inserted and loaded in the box-shaped unit, the mirror edge portion and the inner surface of the peripheral edge of the unit are rubbed against each other, which makes it difficult to smoothly load the unit, and as a result, the mountability of the mirror is deteriorated and a predetermined mount occurs. There was also a risk that it would not be possible to set the mirror in this position.

One of the causes of such a phenomenon is that, for example, the inner peripheral surface of the unit is formed as a convex portion by a stringing process which is one of sheet metal working, and the convex surface is used to prevent the generation of flare light. In some cases, the installation state including the inclination of the mirror may not be constant due to the unevenness of the coated surface. Therefore, if the installation state of such a mirror is not constant, correction and adjustment at the stage of inspection of the finished product after completion of the assembly process will be time-consuming, and not only will the processing cost rise, but also the exposure projection light This may cause a shift in the reflection position and image blur.

Therefore, an object of the present invention is to provide a structure in which a reflecting mirror forming a part of the exposure apparatus can be constantly set and can be easily exchanged and removed in view of the problem in the exposure apparatus forming the exposure scanning system. To obtain an exposure apparatus equipped with.

(Means for Solving the Problem) In order to achieve this object, the present invention provides an exposure for projecting reflected light from a document surface onto an arbitrary surface through a plurality of reflecting mirrors and lenses located between the reflecting mirrors. In the device, a reflecting mirror support member displaceably provided at a position for holding the plurality of reflecting mirrors at a predetermined position and a take-out position enabling the taking out of the reflecting mirrors, and the reflecting mirror support member. An elastic body that is arranged at each vertex position of the virtual triangle on the reflecting mirror mounting surface and has a habit of abutting against the back surface of the reflecting mirror to lift the reflecting mirror from the above-mentioned mounting surface, and the above-mentioned reflecting mirror. The present invention proposes to provide a reflecting surface regulating member which is provided on a member facing the elastic body and which can be brought into contact with the reflecting surface of the reflecting mirror and which sets an inclination angle of the reflecting mirror due to lifting.

(Effect) According to the present invention, the reflecting mirror that floats from the reflecting mirror mounting surface of the supporting member is always at a constant position by the biasing of the elastic bodies that sandwich the reflecting mirror mounted on the reflecting mirror supporting member. By abutting on the reflecting surface regulating member at, the set state in the supporting member is made constant.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 12.

In describing the details of the present embodiment, first, an exposure apparatus that is a premise of the present embodiment will be described, and in the description,
It is preliminarily explained that this embodiment will be described.

FIG. 1 is a perspective view showing an exposure apparatus which is a premise of the embodiment of the present invention. This exposure apparatus is shown as a detail of the exposure apparatus 4 shown in FIG. The same structural parts are designated by the same reference numerals.

That is, the first reflecting mirror (hereinafter referred to as the first mirror) 4C
Is tilted at an angle that can set a predetermined reflection optical path,
It is held by the mirror support unit 11. The first mirror support unit 11 is composed of a housing having a holding portion 11A for the first mirror 4C and a holding portion 11B for the lens 4D described later, and the first mirror holding portion 11A is provided on the inclined bottom plate 11A1. One mirror 4C is placed and fixed.

The details of the first mirror 4C are shown in FIG.
First mirror holding cassette that functions as a mirror support member
After being loaded into 400, it is set on the inclined bottom plate 11A1.

That is, the first mirror holding cassette 400 includes the first mirror 4
Around the C, a box shape is formed so that the upper edge portion and the reflecting surface are exposed so that the first mirror 4C can be lifted up at a plurality of locations on the bottom plate.
1 is fixed.

The first mirror 4C, which is biased to float by the leaf spring 401, is stopped so as not to jump out of the cassette 400 by a locking portion (not shown) provided on the first mirror support unit 11 side. Has been done.

Then, among the rising pieces in the box shape, the piece portions 400a corresponding to both widthwise end edges of the first mirror 4C have a channel-shaped cross section, and the top surface thereof has, for example, a light-shielding member made of foam resin. The member 402 has been spread. A flange 400a1 having a shaft hole is formed on the upper edge side of the first mirror 4C in the rising piece 400a.
By inserting a support shaft (not shown) on the first mirror support unit 11 side into the shaft hole of 00a1, the first mirror support cassette
The 400 is swingably supported.

On the other hand, in the rising piece 400b located on the free end side of the first mirror support cassette 400 described above, at a suitable position, in the embodiment, a uniform position in the width direction, a height corresponding to the thickness of 4C of the first mirror is provided. The protruding piece 400b1 is formed, and the bead 400b10 protruding toward the edge of the first mirror 4C is formed on the protruding piece 400b1. The bead 400b10 is set such that its longitudinal direction is parallel to the thickness direction of the first mirror 4C so that the mounted first mirror 4C can be mounted with less resistance.

A flat surface portion 400c is formed on the free end side of the first mirror support cassette 400, and an appropriate position in the width direction of the first mirror 4C, an equal position in the drawing, is formed on the flat surface portion 400c. Fixing screws 404 that are prevented from coming off via an E-shaped ring 403 are provided at the two obtained locations, and the fixing screws 404 are screwed into screws (not shown) on the first mirror support unit 11 side to make 1 mirror support unit 11
The first mirror support cassette 400 is fixed to the. Therefore, when adjusting the first mirror, by removing the fixing screw 402, the die 1 mirror supporting cassette 400 can be swung to expose the first mirror.

The above-mentioned lens holding portion 11B is composed of a housing continuous with a part of the first mirror holding portion 11A, and is provided on a part of the inclined bottom plate 11A1 of the first mirror holding portion 11A and a wall portion of the holding portion 11A. One end is inserted into the fitting part, and the first mirror
It has a pair of guide shafts 11B1 and 11B2 parallel to the reflected optical axis of 4C.

The guide shafts 11B1 and 11B2 slidably support a lens holding member 12 whose axial ends are the positions of these guide shafts, and the center position between the guide shafts in the lens holding member 12 is set. Has a lens 4D attached.

The lens holding member 12 described above is provided with a support shaft 12A projecting along the width direction at one end in the width direction.
A rotatable cam follower 12B is attached to the tip of the. The cam follower 12B is fitted in the cam groove 13A formed in the cam plate 13 provided in the immovable portion of the copying machine main body, and is displaced according to the shape of the cam groove 13A during movement. The lens holding member 12 is configured to perform

The above-described cam groove 13A has a shape including a stroke based on the criteria described in FIG. 14 and next.

That is, in the present embodiment, regarding the movement of the lens 4C, the movement amount (ΔL ') of the first mirror supporting unit 11 from the position at the same magnification is set to ΔL' = g (m), and based on the function of magnification. The actual amount of movement obtained from this function is as shown by the solid line B in FIG. The lens side is also moved according to the amount of movement of the first mirror 4C, and the amount of movement is within the range indicated by hatching in FIG.

In other words, such a setting is intended to eliminate the adverse effect in the case of only the movement of the first mirror or the movement of only the lens by performing the movement of the first mirror 4C and the movement of the lens in correspondence with each other. The actual movement amount of each optical member is, for example,
The movement amount of the mirror 4C is set to 40 to 60% of the conventional movement amount shown in FIG. 14 (the movement amount shown by the chain double-dashed line A in the figure), and the amount of movement substantially equivalent to this movement amount The movement amount of the conventional movement amount shown in Fig. 14 is set when expanding.
It is set to 100-120%.

Therefore, if the shape of the cam groove 13A is set according to such a reference, it is possible to reduce the movement amount of the first mirror 4C and the movement amount of the lens, and thus, the copying machine. This will eliminate the incentive for the larger size of.

Such movement of the first mirror support unit 11 is performed by a mechanism whose details are shown in FIG.

That is, a boss portion 110 is formed on the side wall of the first mirror support unit 11, and a stationary shaft 14 extending vertically in the copying machine body is fitted in the boss portion 110. , The first mirror support unit 11 via this immovable shaft 14
Are supported so that they can move in the vertical direction.

And, as shown in FIG.
A locking tooth 110A facing the position of 110 is fixed, and the tooth of the cog belt 15 meshes with the locking tooth 110A. Therefore, the cog belt 15 can use the boss portion 110 as a backup member, so that the engagement with the locking teeth 110A can be maintained in a firm state.

On the other hand, the above-described cog belt 15 is hung on a pair of belt pulleys 16 and 17, as shown in the thirteenth illustration, and is movable in accordance with the rotation direction of the pulleys.

Therefore, one of the belt pulleys 16 is supported coaxially with the worm wheel 18, and the worm wheel 18 has
A worm gear 20 fixed to an output shaft 19A of a drive motor 19 composed of a pulse motor capable of normal and reverse rotation is meshed.

In FIG. 3, reference numeral 21 denotes a spreading member of the cog belt 15. The spreading member 21 supports a support plate 21a that rotatably supports the shaft of the other side 17 of the belt pulley, and the support plate 21a. A tension spring hung between the upper end and one of the pins 22, 22 'that is planted in the immovable part in the copying machine.
23 and a fixing screw 241 for fixing the support plate 21a after vertically adjusting the position thereof, and by the biasing force of the tension spring 23, the other side of the Balth pulley via the support plate 21a in the figure. By pulling 17 downward, loosening of the cog belt 15 is prevented.

On the other hand, in the first mirror support unit 11, one end portion in the direction parallel to the width direction of the lens holding member 12 described above has a boss portion.
It is supported like a cantilever by 110, and the other end is
Eccentric sleeve fitted with the tip of a spindle attached to the side wall
The 111 is fitted in a longitudinal elongated hole 24 formed in the immovable portion 24 in the main body of the copying machine so that the 111 can slide in the vertical direction. In the first mirror support unit 11, by rotating the eccentric sleeve 111 in the elongated hole 24, the position of the other end in the width direction can be displaced to adjust the shift of the optical axis with respect to the lens 4D.

Further, in the structure shown in FIG. 1, since the first mirror support unit 11 having such a support structure is in a state where the other end in the width direction is not locked at all, careless sliding is prevented. The structure is provided.

That is, in FIG. 1 and FIG. 3, the bosses 110 and pulleys 25, 26 are disposed at the respective ends in the width direction of the first mirror support unit 11 at positions opposite to the bosses 110, respectively. , 26 are wired with a wire 27 without interfering with the optical path to the lens 4D. And
This wire 27, as shown in FIGS. 3 and 4,
One end of the pulley 28 is fixed to a pin 28 that is locked to an immovable portion in the main body of the copying machine, and the other end bypasses the upper peripheral surface of one of the pulleys 25 and the lower peripheral surface of the other pulley 26. Then, it is fixed to the immovable part 24 of the copying machine.

Therefore, the first mirror support unit 11 is installed at the other end in the width direction, that is, the boss portion by the construction of the wire 27.
The end without the 110 is suspended from and supported by the immovable portion of the copying machine body. And, as shown in FIG. 4, the pin 28 fixing one end of the wire 27 has a thread formed on its shaft, and the tip projection amount of the pin 28 through this screw can be adjusted. Thus, the play and the flexure generated in the first mirror support unit 11 are corrected so as not to obstruct the movement of the first mirror support unit 11 in the vertical direction. The reference numerals 29 and 30 in FIG. 3 indicate pins.
The nut for fixing 28 is shown.

Further, the lens holding portion 11B of the above-mentioned first mirror support unit 11 has a structure for preventing the incidence of ambient light on the lens 4D. Specifically, as shown in FIG. The light shielding plate 120 is attached to the lower surface of the member 12, and the inner surface of the housing forming the lens holding portion 11B has, for example, a surface substantially perpendicular to the incident direction of the projection light and an opposite surface continuous to this surface. Sawtooth-shaped uneven part 121 with an inclined surface
Is formed. By such uneven portions 121, the disturbance light that has entered the lens holding portion 11B is prevented from traveling and is less likely to leak to the rear in the traveling direction. Note that, in order to more reliably prevent such intrusion of ambient light, a low-reflection coating may be applied to the surface of the light shielding plate 120 facing the concave and convex portion 121. The shape of the concave-convex portion 121 may be a tooth having a rectangular shape or a triangular shape as long as the convex portion has a small apex and the concave portion has a deep depth.

On the other hand, a feeler 112 is attached to the boss portion 110 of the first mirror support unit 11 described above, as shown in FIGS. 1 and 6 (A), and the copy machine main body corresponding to the feeler 112 does not move. A home sensor 31 including a photoelectric element is arranged in the section 24.

The home sensor 31 is for detecting the position of the first mirror unit 11 at the same magnification, and is the feeler 112.
When the light is blocked, it is detected as the enlargement time including the same magnification, the output signal is output as (HIGH), and conversely, the time when it does not correspond to the feeler 112 is detected as the reduction time and the output is output. Output the signal as (LOW).

The home sensor 31 is supported by a bracket 32 whose top portion is bent at a right angle, and the bracket 32 is fitted in a long hole 32a having a long axis parallel to the moving direction of the first mirror support unit 11. 6th with guide pin 32A
As shown in FIG. 3B, the guide pin 32A is pressed against the immovable portion 24 via the disc spring washer 32b penetrating therethrough. An adjusting screw 33 having an axial direction parallel to the moving direction of the first mirror supporting unit 11 is penetrated through the top of the bracket 32, and the adjusting screw 33 is rotated to adjust the protrusion amount. Thus, the corresponding position between the bracket 32 and the home sensor 31 can be adjusted, and after the adjustment is completed, the fixing screw 32B located on the same side as the guide pin 32A can be tightened for accurate position adjustment.

In such a position adjustment structure of the bracket 32 with respect to the home sensor 31, while the position adjustment is performed, since the bracket 32 is kept pressed by the immovable portion 24 by the disc spring washer 32b, when the fixing screw 32B is loosened. Moreover, the bracket 32 does not float from the immovable portion 24. Therefore, when the fixing screw 32B is fastened again, there is no problem that the position shifts due to the rotational moment that occurs when fastening the bracket 32, which tends to occur when the bracket 32 floats.
It is possible to maintain the state where the position of 31 is accurately aligned with the position of the feeler 112.

The drive for moving the first mirror support unit 11 described above is performed by the drive motor shown in FIG.
The drive control is performed by means of 19 and is shown in FIGS. 6 and 7.

That is, in the present embodiment, the movement start position of the first mirror support unit 11, that is, the initial position is set to the position at the same magnification detected by the home sensor 31 shown in FIG. 6, and is moved from an arbitrary position. Also in the case of performing, after returning to the initial position once, the movement to the position according to the magnification is started.

That is, FIG. 7 shows the position of the first mirror support unit 11 at the same magnification, the position at the time of enlargement, the position at the time of contraction, and the position at the time of overrun by the symbols ,, respectively. The first mirror support unit 11 in the position is
In order to cancel the backlash of the gear or the hysteresis of the home sensor 31 in the mechanism for driving the moving body of this kind, in other words, in order to make the return condition to the initial position constant, it is operated from one direction and stopped. I am doing it.

By the way, in the above-mentioned return operation to the initial position,
In the case of the position shown by ,, even though the initial position is once reached, it is further moved to the overrun position and then moved toward the initial position. This is because the feeler 11 in the first mirror support unit 11 depends on the moving direction of the first mirror support unit 11.
This is to prevent an error from occurring in the corresponding position between 2 and the home sensor 31.

That is, in FIG. 7, for example, the moving direction of the first mirror support unit 11 is opposite between the case of moving from the enlarged position to the initial position and the case of moving from the contracted position to the initial position. When moving in the direction of gravity, the home sensor 31 at the time when it corresponds to the home sensor 31 may be caused by the difference in the vibration generated during the movement.
The operating speed of may differ. Therefore, the acceleration changes as a cause of the speed fluctuation, and as a result, the tension applied to the cog belt 15 also changes, the extension amount of the cog belt 15 also changes, and the position after stopping shifts. There is a fear that accurate movement detection to the initial position cannot be performed. Therefore, in the present embodiment, by performing the movement operation to the initial position by the above-described method, the movement condition for the home sensor 31 in all cases to move to the initial position from a position of equal size or other than this. Is made constant.

By doing this, for example, by operating at a low speed or increasing the overrun amount, the double action as described above, that is, once the initial position is reached, the double action is performed to move the initial position again. It is also possible not to carry out the operation of moving to the position. However, in this case, there is a drawback that the operation time becomes long, but in the present embodiment, it is possible to perform a reliable initial operation without causing such a drawback. The position can be detected. Further, even when a metal wire or the like is used, it is effective when applied when there is a risk that the wire will be stretched.

Then, such movement control is executed based on the flowchart shown in FIG.

That is, although not shown, this control is performed for the driver of the drive motor 19, and the home sensor 31
Output is "HIGH", that is, when the output for detecting that the first mirror support unit 11 is in the normal position or the enlarged position is output, the output of the home sensor 31 is inverted, that is, the output is The drive motor 19 is reversely rotated until it becomes (LOW), and the first mirror support unit 11 is lowered. Further, when the output of the home sensor 31 is (LOW), that is, when the so-called first mirror support unit 11 is in the contracted position, the home sensor 31
Drive motor 19 is rotated in the forward direction until the output of is high, and the first mirror support unit 11 is raised.
When the output of 31 becomes (HAIGH), it is stopped for an arbitrary time, that is, the time corresponding to the access time for processing in the driver (about 10 to 50 ms), and then the home sensor 31
Rotate in reverse until the output of turns to (LOW). In this way, when moving from each position, the drive motor 19 is reversely rotated and stopped within an arbitrary time after the output of the home sensor 31 becomes (LOW). The overrun amount at this time is 0.5 to 5 mm, and is 2 mm in this embodiment.
In order to suppress an operation error due to mechanical vibration, the drive motor 19 is normally rotated and stopped until the output of the home sensor 31 becomes (HIGH) after the stop for an arbitrary time described above.

Further, on the side where the boss portion 110 is arranged in the first mirror support unit 11 described above, as shown in the first illustration, there is provided a roller 40 which is attached to a spindle provided on a side wall and is rotatable. The roller 40 is a cam surface of a drive cam 42 which serves as a drive member for displacing the second mirror support unit shown in FIG.
It is in contact with 42A.

That is, the drive cam 42 is composed of a swinging member whose base end is pivotally attached to the shaft 24b which is planted in the immovable portion 24 in the copying machine, and the helical spring 43 which is hung between the drive cam 42 and the immovable portion. 9 has a habit of rotating counterclockwise in FIG. 9 and comes into contact with the roller 40. The cam surface 42A of the drive cam 42 that contacts the roller 40 is set to have a shape that allows the second mirror 4E to be positioned at a predetermined position according to the amount of movement of the first mirror support unit 11. Has been done. The position change of the second mirror 4E due to the cam surface 42A is, for example, in FIG. 9 when the first mirror support unit 11 changes from the position shown by the solid line to the position shown by the chain double-dashed line in FIG. It moves backward in the direction perpendicular to the reflecting surface of the second mirror 4E toward the position of the chain double-dashed line indicated by reference numeral 1.

A long hole 42B having a long axis extending in the radial direction is formed on the swing end side of the drive cam 42.
2B includes a cam follower 44 of the second mirror support unit 41.
Is supported.

That is, it is installed in the copying machine and the above-mentioned second
The second mirror support bracket 45 equipped with the mirror support unit 41 supports both ends in the axial direction, and the second mirror 4E
Is provided with a guide shaft 46 extending in a direction perpendicular to the reflection surface thereof, and one end of the second mirror support unit 41 in the width direction is slidably supported by the guide shaft 46 as shown in FIG. ing. A support shaft 41A having a rotatable roller 41B at the tip thereof is attached to the other widthwise end of the second mirror support unit 41, and this roller 41B is formed on the wall on the bracket side and serves as a guide shaft 46. Long hole 45A with long axis in parallel direction
It is designed to roll inside.

In the second mirror support unit 41 described above, a cam follower 44 is provided slidably in the axial direction of the guide shaft 46 on the side wall located at one end in the width direction on the side corresponding to the guide shaft 46.

That is, the cam follower 44 includes a sliding plate 44A whose longitudinal direction is set parallel to the axial direction of the guide shaft 46, and a long shaft parallel to the sliding direction formed at a plurality of points on the sliding plate 44A. With the guide pin 44B penetrating through the long hole having the and the disc spring washer 44B1 located between the guide pin 44B and the sliding plate 44A, and the fixing screw 44C penetrating the long hole similarly to the guide pin 44B. A roller 44D that is supported and is fitted into the elongated hole 42A of the drive cam 42 described above is attached to one end in the longitudinal direction thereof.

This cam follower 44 is a member that can prevent the displacement of the sliding plate 44A that occurs when the fixing screw 44C is tightened, like the positioning structure shown in FIG. 5 for the guide pin 44B, the disc spring washer 44B1 and the fixing screw 44C. As
Adjusting the position of the roller 44D with the long hole 42A of the drive cam 42, the adjustment screw 44E provided on the other end of the sliding plate 44A in the longitudinal direction is used.
It can be obtained by rotating the.

On the other hand, in FIG. 10, the second mirror support unit 41 has
A structure for supporting the second mirror 4E is provided.

That is, the second mirror supporting portion is a fixing portion for fixing the mirror supporting portion 41C formed on the frame having a surface perpendicular to the guide shaft 46 and the second mirror supporting cassette 50 loaded in the mirror supporting portion 41C. It is composed of 41D and.

The above-mentioned second mirror flat surface supporting portion 41C includes the upper and lower portions of the second mirror supporting cassette 50 on the reflection surface side of the second mirror 4E and the second mirror in the second mirror supporting cassette 50.
A reflection surface upper partition surface 41C1, a reflection surface lower partition surface 41C2, and a rear partition surface 41C3, which respectively stop the approximately central portion in the height direction of 4E, are formed, and both side positions in the width direction of the reflection surface upper partition surface 41C1. An adjustable screw 41C4 that can be moved back and forth is provided on the above, so that the tilt angle of the reflection surface of the second mirror 4E fixed to the second mirror support cassette 50 can be adjusted. Further, pins 41C5 projecting toward the reflection surface of the second mirror 4E are fixed to both sides in the width direction of the reflection surface lower partition surface 41C2, and when adjusting the tilt angle of the second mirror 4E described above. The reflection surface is positioned as a reference point of the.

The second mirror support cassette 50 loaded in the second mirror support portion of the second mirror support unit 41 in the second mirror support unit 41 having such a structure has the structure shown in FIGS. 11 and 12. ing.

That is, the second mirror support cassette 50 functions as a second mirror support member, and is formed in a box shape removed so that the upper edge portion and the reflection surface can be exposed around the second mirror 4E, The second of the rising pieces in the box shape
The piece 50a, 50b corresponding to one side edge and the lower edge of the mirror 4E is provided with a folding piece 50a for locking the reflecting surface of the second mirror 4E which is lifted by the bias of the leaf spring 51 attached to the bottom plate.
1, 50b1 are provided.

Then, of the rising pieces described above, at the position corresponding to the other side edge and the position corresponding to the upper edge of the second mirror 4E,
Protruding pieces 50c and 50d are formed by extending the bottom plate. The protruding pieces 50c and 50d are provided with screw holes 41D (tenth portion) provided in the fixing portion 41C1 of the second mirror supporting unit 41.
A fixing screw 52 that can be screwed into (see the drawing) is held via an E-shaped ring 53.

In addition, the folding piece 50 corresponding to one of the side edges of the first mirror 4E.
A pin 54 is fixed to the outer surface of the rising piece 50a having a1. The pin 54 is used for the second mirror support unit.
The loading position of the second mirror 4E can be determined by engaging with a positioning groove 41E (see FIG. 10) formed in 41.

On the other hand, the second mirror loaded in the second mirror support cassette 50
The lower edge of the mirror 4E is clamped and fixed by an upper open channel type clamp member 55 mounted between the lower folding piece 50b1 on the second mirror supporting cassette 50 side and the bottom plate. Therefore, the clamp member 55 is
A bead-shaped locking protrusion 55a that fits into the locking hole formed in the folded piece 51b1 is formed, and the second mirror 4E is fixed by fitting the locking protrusion 55a into the locking hole of the clamp member. You can do it. In such a locking structure, the clamp member 55 is made of a material having elasticity to some extent, such as spring steel, so as to facilitate fitting into and disengaging from the locking hole. The clamp member 55 is used by previously being attached to the lower edge of the second mirror or previously attached between the folding piece 50b1 and the bottom plate.

Since the present embodiment has the above-described structure, the first mirror holding cassette in the first mirror support unit 11 has the first mirror holding cassette.
When the mirror is loaded, the first mirror abuts on the contact portion by the bias of the leaf spring, so that the first mirror is set at a predetermined position, and this state is always obtained constantly.

Further, when moving such a first mirror holding cassette to the exposed position of the first mirror, it becomes easy by removing the fixing screw. Further, when the first mirror is loaded into the first mirror holding cassette, the peripheral edge of the first mirror, especially the lower edge, slides on the bead, so that the sliding resistance is not so large. Is loaded.

On the other hand, also in the second mirror support unit, the second mirror is similarly loaded and exposed.

As described above, according to the present invention, in the exposure device for projecting the original image on the photoconductor through the plurality of reflecting mirrors and the lenses positioned between these reflecting mirrors, in the supporting structure of the reflecting mirrors, The reflecting mirror is attached so as to be lifted from the mounting surface, and the reflecting mirror in the lifted state can be locked at a predetermined position, so that it is possible to always set in a constant state. Therefore, it is possible to simplify or omit post-processing after completion of the assembly process. Further, even when the reflecting mirror is loaded, the sliding resistance can be reduced, and the loading operation can be facilitated and the positional deviation after loading can be suppressed. Further, even in the exposing operation for removing, replacing, etc. of the reflecting mirror, it suffices to simply remove the screw fixing the supporting member of the reflecting mirror, whereby a novel structure capable of satisfying the above-mentioned requirements. Is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a supporting structure of a first reflecting mirror in an essential part of an exposure apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view showing details of a first reflecting mirror mounting portion in the structure shown in FIG. 3 and FIG. 3 are perspective views showing the drive mechanism of the main part shown in FIG. 1, FIG. 4 is a view in the direction of the arrow IV in FIG. 1, and FIG. A sectional view taken along the arrow V-V,
FIG. 6 (A) is a perspective view showing details of a portion indicated by reference numeral VI in FIG. 2, and FIG. 6 (B) is a reference numeral BB in FIG. 6 (A).
FIG. 7 is a diagram for explaining the operation of the drive mechanism shown in FIG. 3, and FIG. 8 is a flowchart for explaining the operation of the drive mechanism shown in FIG. FIG. 9 is a side view showing an essential part of a variable power exposure apparatus according to an embodiment of the present invention, FIG. 10 is a perspective view showing the structure of a second reflecting mirror supporting part in the essential part shown in FIG. 9, and FIG. Is the second shown in FIG.
FIG. 12 is a perspective view showing a part of the mounting structure of the second reflecting mirror in the reflecting mirror supporting portion, FIG. 12 is a view in the direction of the arrow XII in FIG. 11, and FIG. 13 is an image using a variable power exposure apparatus. FIG. 14 is a model diagram for explaining an example of the forming apparatus, and FIG. 14 is a diagram for explaining a moving state of the optical member in the exposure apparatus during zooming. 1 ... Copier, 2 ... Photoconductor, 4 ... Exposure device, 4C ...
1st mirror, 4D ... Lens, 11 ... 1st mirror support unit, 11A ... 1st mirror holding part, 11B ... Lens holding part, 11B1, 11B2 ... Guide shaft, 12 ... Lens holding member,
12B …… Cam follower, 13 …… Fixed part, 13A …… Cam groove,
15 …… Cog belt, 16, 17 …… Belt pulley, 18 ……
Worm wheel, drive motor, 20 ... Worm gear,
25, 26 ...... Pulley, 27 ...... Wire, 28 ...... Wire extension tension adjusting pin, 40 ...... Roller, 41 ...... Second mirror support unit, 42 ...... Driving cam, 42B ...... Elongated hole, 44 ... … Cam follower, 44D… Roller that fits into slot 42B, 46 …… Guide shaft, 50 …… Second mirror support cassette, 50b1 …… Folding piece, 51 …… Flat spring, 52 …… Fixing screw, 55… … Clamping member, 55a …… Bead, 400 …… First mirror holding cassette,
400b …… Folding piece, 400b1 …… Bead, 401 …… Leaf spring, 404 …… Fixing screw.

Claims (1)

[Scope of utility model registration request] 1. An exposure apparatus for projecting light reflected from a document surface onto an arbitrary surface through a plurality of reflecting mirrors and lenses positioned between the reflecting mirrors, wherein the plurality of reflecting mirrors are held at predetermined positions. A reflecting mirror support member that is displaceable between a posture and a taking-out posture that allows the reflecting mirror to be taken out, and is arranged at each vertex position of a virtual triangle on the reflecting mirror mounting surface of the reflecting mirror supporting member. And the elastic body having the habit of coming into contact with the back surface of the reflecting mirror to lift the reflecting mirror from the above-mentioned mounting surface, and the member facing the elastic body with the reflecting mirror interposed therebetween. An exposure apparatus in an image forming apparatus, comprising: a reflection surface regulating member that can be brought into contact with a reflection surface of a mirror and sets an inclination angle of the reflection mirror due to lifting.