JPS61110128A - Exposure optical device - Google Patents

Abstract

PURPOSE:To drive an optical unit without any slip by folding back intermediate parts of toothed belts in the opposite directions and winding them a couple of toothed pulleys provided to the 2nd unit. CONSTITUTION:The 1st optical unit 54 consists of an exposure lamp 4 which irradiates an original platen surface with light, a mirror 5 which reflects reflected light from the original platen surface in a specific direction, and the 1st carriage50, and the 2nd optical unit 55 consists of mirrors 6 and 7 which reflect a light image reflected by; the 1st optical unit 54 to a lens side and the 2nd carriage 51. Toothed driving pulleys 62 are provided at one-terminal sides of the optical units 54 and 55 in the moving direction and driven toothed pulleys 63 are provided at the other-terminal sides; and the couple of pulleys 66 and 67 are provided to the 2nd optical unit. The toothed belts 68 are wound around pulleys 62 and 63, and 66 and 67 so that the intermediate parts of the toothed belts 68 are folded back in the opposite directions, and the 2nd optical unit 55 is moved a half as fast as the 1st optical unit 54.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention is applied to, for example, an electronic copying machine, and includes an exposure light source that irradiates light onto a document placement surface and a light source that reflects reflected light from the document placement surface in a predetermined direction. A first optical unit having a reflecting member is moved along the IIKI scanning surface at a speed of ■, and a second optical unit having a reflecting member that reflects the optical image reflected by the first optical unit toward the lens side. By reciprocating the optical unit in the same direction as the first optical unit at a speed of 1/2 of the speed V, the document placed on the document placement surface is scanned and an image is formed on the exposed area. The present invention relates to an exposure optical device configured as described above.

[Technical background of the invention and its problems] Usually, in an exposure optical device for a copying surface with a fixed original type, there is an exposure light source that irradiates light onto a document placement surface and a light source that reflects reflected light from the document placement surface in a predetermined direction. Optical unit operation for moving a first optical unit having a reflecting member and a second optical unit having a reflecting member that reflects an optical image reflected by the first optical unit toward a lens (not shown). The means has the following structure.

In other words, the wire has both ends fixed around a pair of booms provided in the second optical unit, and the wire is wound around the middle part of the wire so as to be folded in opposite directions, and the drive boom is driven by a motor. By winding and unwinding the wire as it rotates, the first optical unit is moved back and forth in the same direction at a speed of V, and the second optical unit is moved at a speed of one-half of the speed (■). .

However, in the past, since the driving force of the motor was transmitted using wires, slips were likely to occur.

When this slip occurs, since the optical system is driven at two or more points, the optical system is tilted and the copied image is tilted. In addition, since the wire is wound around the pulley multiple times to prevent slippage, assembly is very troublesome.

[Object of the Invention] This invention has been made in view of the above circumstances, and its objects are to enable easy assembly, to drive the optical unit without slipping, and to drive the optical unit smoothly without generating vibrations. An object of the present invention is to provide an exposure optical device that can maintain a stable driving state and provide good and stable exposure scanning.

[Summary of the Invention] The present invention provides a method for winding a toothed belt in the middle of a pair of toothed bools provided in a second unit so as to fold it back in opposite directions, and also winding the toothed belt in the opposite direction. 1
By connecting the optical units, as the drive pulley around which the toothed belt is wound rotates, the first optical unit is moved at a predetermined speed, and the second optical unit is moved at a speed that is twice the moving speed of the first optical unit. It is designed to move in the same direction at one-times the speed.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 schematically shows the interior of a copying machine as an image forming apparatus. In other words, 1 is the copying machine main body,
A document table (transparent glass plate) 2 for supporting a document is provided on the top surface of the main body 1.

On the lower surface side of the document table 2, there is an exposure optical system 10 consisting of an exposure lamp 4 that reciprocates in the direction of the arrow in the figure, a mirror 5, 6, 7, a lens block 8 that is movable in the optical axis direction, and a fixed mirror 9. By optically scanning the surface of the document using the optical system 10, an image of the document is formed on the surface (slit exposure). The photosensitive drum 11 rotates in the direction of the arrow shown in the figure, and the surface is first charged by the charging device 12, and then the image is exposed to slit light to form an electrostatic latent image on the surface. This electrostatic latent image is turned into a visible image by applying toner by a developing device 13, and is then neutralized by a pre-transfer static elimination lamp 14.

On the other hand, the paper (image-forming object) P is taken out one by one from the selected upper paper feed cassette 15 or lower paper feed cassette 16 by the feed-out row 517 or 18, passes through the paper guide path 1 or 20, and registers. is guided to the roller 21, and the transfer portion 22 is guided by this registration roller 21.
You will be guided to. Here, the paper feed cassettes 15 and 16 are detachably provided at the lower right end of the main body 1, and one of them can be selected using an operation section (not shown). However, the transfer section 2
2, the paper P sent to the transfer charger 23 comes into close contact with the surface of the photoreceptor drum 11, and the toner image on the photoreceptor drum 11 is transferred by the action of the charger 23. . The transferred paper P is electrostatically peeled off from the photoreceptor drum 11 by the action of the peeling charger 24 and conveyed through the paper conveyance path 25, and a heat roller 26 serving as a fixing device is provided at the end of the sheet conveyance path 25. The transferred image is fixed by passing through this area. And the paper P after the appetizer is
The sheet is discharged from the main body 1 through the discharge port 29 by the discharge roller 27 and guided to the tray 28 . Further, the photosensitive drum 11 after the transfer is returned to its initial state by removing residual toner on the surface by a cleaner 29 and erasing afterimages by a static elimination lamp 30. The tray 28 is provided so as to be freely attachable.

FIG. 2 shows an example of the drive source configuration of each drive unit of the copying tray configured as described above, and is composed of the following motors. That is, 31 is a lens motor, which is a motor for moving the position of the lens block 8 for performing magnification change.

A mirror motor 32 is a motor for changing the distance (optical path length) between the mirror 5 and the mirror 6.7 for changing the magnification. A scanning motor 33 is a motor for moving the exposure lamp 4, the mirror 5, and the mirror 6.7 for scanning the original. A shutter motor 34 is a motor for moving a shutter (not shown) for adjusting the charging width of the photosensitive drum 11 by the charger 12 during zooming. A developing motor 35 is a motor for driving the developing roller of the developing device 13 and the like. A drum motor 36 is a motor for driving the photosensitive drum 11. 37 is a fixing motor, which connects the paper conveyance path 25 and the fixing roller pair 2.
6 and the paper discharge roller 27. A paper feeding motor 38 is a motor for driving the delivery rollers 17 and 18. A paper feeding motor 39 is a motor for driving the pair of registration rollers 21. A fan motor 40 is a motor for driving a cooling fan (not shown).

FIG. 3 shows a drive mechanism for driving the optical system 10 back and forth. That is, the exposure lamp 4 and the mirror 5 are supported by the first carriage 5o, and the mirror 6 is supported by the first carriage 5o.
．． 7 is supported by a second carriage 51, and these first and second carriages 50.51 are connected to guide rails 52.53.
It is guided by and can freely move in parallel in the direction of arrow a.

Here, a first optical unit 54 is constituted by the exposure lamp 4, mirror 5, and first carriage 50.
.

ing. Also, the mirror 6.7 and the second carriage 51
A second optical unit 55 is configured.

The first optical unit 54 and the second optical unit 55 are mounted and supported as shown in FIG. It has a configuration that allows it to move at a speed of 1/2 of V.

That is, the upper horizontal piece portion 5 is provided on the mutually opposing surfaces of the rear frame 56 and the front frame 57 which are arranged in parallel at a distance.
A guide frame 58.58 is attached parallel to the guide frames 6a and 57a, and sliders 59 attached to the lower surfaces of both ends of the guide frames 58.58 are in sliding contact with the first optical unit 54, and a second optical unit 55 is installed.' In this way, the first optical unit 54 and the second optical unit 55, which are provided movably on the guide frame 58, 58, are moved in a predetermined direction at a predetermined speed by the optical unit actuating means 60. It has become.

The optical unit operating means 60 has the following configuration. That is, a drive shaft 61 is horizontally mounted corresponding to one end side in the moving direction of the optical unit 54.55, and toothed drive pulleys 62.62 are provided at both ends thereof, that is, on the outside of both frames 56.57. installed.

Further, a toothed driven pulley 63 is rotatably provided on the outside of the frame 56.57 via a support shaft 64 corresponding to the other end of the optical unit 54.55 in the moving direction.

Both ends of the first carriage 5o of the first optical unit 54 protrude outside the frame 56.57, and both ends of the second carriage 51 of the second optical unit 55 protrude outside the frame 56.57. The boob attachment part 65a, 65b is vertically folded back along the side surface, and a pair of pulleys 66, 67 acting like movable pulleys are respectively attached thereto.

Further, a midway portion of a toothed belt (timing belt) 68 is wrapped around each pulley 62, 63, 66, 67 in a predetermined state. That is, the belt 68 with one end fixed to the fixture 69 is attached to the driven bobbly 63g! After being pulled out to the M1 pulley 66 of the second optical unit 55 and turned back, it is wound around the drive pulley 62 and turned back to the driven pulley 63 side.

Next, the belt 68 is wound around the driven pulley 63 and around the 27th belt 67 of the second optical unit 55 and folded back, and then the other end is fixed to the fixture 70.

Further, both ends of the first carriage 50 are connected to belts 68.
is fixed directly to the

On the other hand, the drive shaft 61 is configured to move via the motor 33 and a timing belt 71.
The drive pulleys 62, 62 around which the number 8 is wound are driven in the forward direction or in the reverse direction. The first optical unit 54, which is directly fixed to the belt 68, moves at a speed of 2 to the second optical unit, which is attached with a pulley 66, 67, which functions as a movable pulley and is wrapped around the belt 68. 55 is configured to move at a speed that is one-half of the speed (2).

As mentioned above, since the optical unit drive means is made up of a toothed belt and a toothed boot, the driving force from the motor can be transmitted to the optical unit without slipping, unlike conventional methods. Compared to the case where the wire is wrapped around the boob several times, it only needs to be wrapped once, making it easier to assemble.Furthermore, since the belt is more rigid than wire, it can prevent the negative effects of vibrations caused by resonance, etc. .

[Effects of the Invention] As detailed above, according to the present invention, assembly is easy and the optical unit can be driven without slipping.
It is possible to provide an exposure optical device in which the optical unit can be maintained in a smooth driving state without generation of vibration, and good and stable exposure scanning can be obtained.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a sectional view schematically showing the configuration of an image forming unit device that employs the exposure optical device of the present invention, and FIG. 2 is a configuration example of each drive source. FIG. 3 is a perspective view showing operating means of the first and second optical units of the exposure optical apparatus. 2... Original table, 4... Exposure lamp, 5.6.7.9
... Lamp, 8... Lens block, 10... Optical system, 11... Photosensitive drum, P... Paper (image forming object), 33... (Scanning) motor, 50 ...First carriage, 51...Second carriage, 54...
First optical unit, 55...Second optical unit, 60
...Optical unit actuating means, 61... Drive shaft, 62
...(Toothed) driving pulley, 63...(Toothed) Driven pulley, 66.67...(Toothed) pulley, 68.
...(toothed) belt, 69.70...fixing device.

Claims (1)

[Claims] In an exposure optical device that scans a document placed on a document placement surface and forms an image on an exposed area, an exposure light source that irradiates light onto the document placement surface and reflected light from the document placement surface. a first optical unit that has a reflective member that reflects light in a predetermined direction and is movable back and forth along a document placement surface;
The first optical unit is provided so as to be movable back and forth in the circumferential direction.
a second optical unit having a reflecting member that reflects the optical image reflected by the optical unit toward the lens side;
The toothed belt is wound around a pair of toothed pulleys provided in the unit so that the middle part of the toothed belt is folded back in opposite directions, and the first optical unit is connected to the toothed belt. The first optical unit is moved in the same direction at a predetermined speed and the second optical unit is moved in the same direction at a speed that is half the moving speed of the first optical unit as the drive pulley around which the belt is wound rotates. 1. An exposure optical device comprising an optical unit operating means.