JPS60232540A - Lighting device of electronic copying machine - Google Patents

Abstract

PURPOSE:To reduce the load on a driving method and scan scanning bodies at high speeds, and to prevent the copying machine frame from vibrating by scanning a lighting means and an image formation optical system separately and indenpendtly. CONSTITUTION:The lighting means is provided with a lamp carriage 11 which is guided to a guide rail 14 extending along a platen 13 and moves forth and back on the guide rail 14 through a driven cable 15 connected to its front and rear ends, and the cable 15 is driven by the 1st servo-motor 16. Projection light from the surface of an original 12 irradiated with light from a lamp 10 forms an image on a photosensitive drum 20 through the image formaton optical system. The image formation optical system consists of a full-rate mirror 21 and a half-rate mirror 22 which move synchronously with the lamp carriage 11, a fixed lens 23, and the 4th mirror 24. The full-rate carriage 25 and half-rate carriage 26 to which the mirrors 21 and 22 are fitted are driven by the 2nd servo- motor 29 through a cable 28 to scan.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lighting device for a slit exposure type electronic copying machine.
In particular, the present invention relates to an illumination device in which an illumination means and an imaging optical system are scanned separately and independently.

(Prior art) Conventional slit exposure a! ! As shown in FIG. 1, the illumination device of the #L child copying machine exposes the document (vA not shown) on the platen 6 to a slit using a lamp 1 that moves along the platen 6 (in the horizontal direction in this figure). ,? An electrostatic latent image is formed on the surface of the photosensitive drum 4 through an imaging optical system consisting of a combination of M number of mirrors 2 and lenses 3. This illumination device has a configuration in which the lamp 1 and parts 2m and 2b of the imaging optical system are integrally scanned by a single drive system 5, but as a result, the load placed on the drive system 5 is large. It was difficult to perform high-speed scanning of the lamp 1 and the optical system.

Further, when the scanning body formed as described above is scanned at high speed by a drive system having a large output, vibration is generated in the main body of the copying machine, and this vibration appears as image blurring during image formation, which is undesirable. In particular, in a color copying machine, for example, in which a plurality of lamps having different light qualities are arranged, the above-mentioned drawbacks become even more pronounced because the weight of the scanning body increases. On the other hand, since color copying machines repeat the side lighting process for each wi number of lamps, their productivity is lower than that of black and white copying machines, and therefore high-speed scanning is required.

(Object of the invention) The object of the present invention was made in view of the above-mentioned drawbacks,
In particular, an object of the present invention is to provide an illumination device that enables high-speed scanning of a scanning object and does not cause vibrations in the copying machine body by reducing the load on driving means for the illumination system and imaging optical system in a color copying machine. .

(Structure of the Invention) That is, the above object of the present invention is to provide an illumination device for an electronic copying machine that uses a moving light source and an imaging optical system to illuminate an electrophotographic photoreceptor to form a slit image. an imaging optical system comprising a plurality of mirrors and lenses; and a driving means for driving the illumination means and the imaging optical system, the illumination means and the imaging optical system being separated and independent. This is achieved by being scanned.

(Example) Hereinafter, an example of the present invention will be described in detail using the drawings. FIG. 2 illustrates an illumination system for a color copying machine comprising a plurality of lamps 10 of varying light quality.

The lamp 10 having a plurality of monochromatic lights is a red lamp 10a.
, a blue lamp 10b, and a green lamp 10C are provided on one lamp carriage 11, and constitute illumination means movable along the platen 16 on the back side of the platen 13 on which the original 12 is placed. That is, the illumination means includes a lamp carriage 11 guided by a guide rail 14 along the platen 13, and a cable 15 connected to the front and rear ends.
It is provided so that it can reciprocate on the guide rail 14 by driving. The cable 15 is stretched over a capstan pulley 17 and an idler pulley 18 driven by a first servo motor 16, and both ends thereof are connected to the lamp carriage 11. Also, lamp carry 1
1 is provided with a reflector 19 for each lamp as in the conventional case.

Projected light from the surface of the document 12 irradiated by the lamp 10 forms an image on the photosensitive drum 20 via an imaging optical system, which will be described later.

The imaging optical system includes a full rate mirror 21 and a half rate mirror 22 that move in synchronization with the lamp carriage 11.
It is composed of a fixed lens 23 and a fourth mirror 24. The full rate mirror 21 is attached to a full rate carriage 25, and the half rate mirror 22 is attached to an 8-7 rate carriage 26. Furthermore, the half rate mirror 26 is attached to a rotatably provided bar 7 rate pulley 27. supported. The full rate F carriage 2511 and the half rate carriage 26 are scanned by being driven by a second servo motor 29 via a cable 28 provided in the same manner as driving the illumination means. That is, the table 28 is stretched around the capstan pulley 30 and the idler pulley 61, both ends of which are connected to the front and rear ends of the full rate carriage 25, and the table 28 is wound around the -7 rate pulley 27. The half-rate pulley 27 is provided to be relocatable by moving the cable 28.

Further, the half-rate pulley 27 is supported on a cable 62 separately stretched along the platen 16 to support the load of the bar 7-rate carriage 26. Note that the full rate F carryage 25 and the half rate carryage 26 relatively move at a speed ratio of i:%.

Additionally, three position sensors 33 are disposed at predetermined positions along the travel path of the full rate carriage 25, respectively.

The lighting device provided as described above is powered by a second servo motor 29.
When the optical system begins to rotate and the optical system begins to move, the driving system of the illumination means turns on a predetermined lamp 1o, and the first servo motor 16 is driven to start moving and scanning along with the optical system. That is, as the full rate carry 25 moves, the normal rate carry 25 moves to the predetermined position sensor 33a.
When passing the corresponding lamp 1o, for example, red lamp 1
As soon as ゜a lights up, it starts moving in sync with the optical system,
The original 12 is subjected to slit exposure. When the exposure of the original w412 surface by the red lamp 1°a is completed, the lamp 1°a is turned off. At the same time as the lamp goes out, two sir'%-416,2
9 starts reversal and moves the lamp system and optical system back.

When the lamp carriage 11 returns to the second position sensor 33b, two ? -f motors 16 and 29 turn to normal rotation again,
The blue lamp 10'b is turned on and the same exposure process as the red lamp 1oa is repeated. The exposure process for the green lamp 100 is performed in the same manner, and the entire exposure process is completed.

As described above, in this embodiment, the illumination means and optical system are separated and independent,
In addition, each of them is driven by a separate servo motor Is, 29.

FIG. 3 shows another embodiment of the invention.

The illumination device shown in FIG. 2 includes six movable lamps 40 on the back side of the platen 16, as in the first embodiment. Each lamp 40 is installed on a separate lamp carriage 41, and each lamp carriage is arranged on the same plane and scanned independently in the order of the exposure process. Each lamp carriage 41 has a capstan pulley 4
2 and a cable 44 stretched across the idler pulley 46
The capstan pulley 42 is driven to reciprocate along the platen 13. Each capstan pulley 4
2 is connected to a gear 46 via a clutch 45.

The gear 46 is driven by a shaft 48 directly connected to one servo motor 47.

Further, this illumination device includes a set of imaging optical systems that are driven separately from the above-mentioned lamp system and that move under the control of the driving of the lamps. This imaging optical system has the same structure as the first embodiment, so the same reference numerals will be used and the explanation will be omitted. This imaging optical system is driven via a clutch 49 by the same servo motor 47 as the illumination means. Further, position sensors 50 and 51 are similarly arranged to detect the respective predetermined positions of the illumination means and the optical system.

Next, describing the exposure process of this illumination device, a predetermined lamp 40, for example, a red lamp 40a, is turned on,
When the clutch 45& of the drive system is connected, the lamp carriage 41a starts scanning. Also, lamp carry 4
Simultaneously with the scanning of 1&, the clutch 49 of the optical system is connected and the imaging optical system starts moving along with the red lamp 40&.

When the red lamp 40& finishes scanning the image by moving in one direction, the lamp 40& is turned off, and at the same time the clutch 45
A is cut out and running is stopped. On the other hand, the servo motor 47
At that point, reverse rotation starts, and only the image forming optical system is moved back by the clutch 49 of the image forming optical system that is subsequently connected. When the imaging optical system moves to the position sensor 51, the servo motor 47 turns forward again and the blue lamp 40b is turned on.
Turn on and repeat the same scan. Finally green lamp 40
When c is turned on and image scanning is completed, the clutches 45 of all the lamps 40 and the clutch 49 of the imaging optical system are turned on.
are connected and moved back together to complete the exposure process.

In the illumination device configured in this way, the weight of the lamp carriage 41 that is scanned in each exposure cycle is the same as that of a conventional black-and-white copying machine, and the weight increases only during the backward movement when the last exposure cycle is performed, resulting in a large load. Become. However, the vibrations that occur in the copying machine at this time can be prevented by reducing the rotation of the servo motor 47 to suppress the backward movement speed, or by configuring the copying machine so that the next copy is started after a predetermined period of time has elapsed. Generally, it is possible to set the above-mentioned time before the start of the next copy.

FIG. 4 illustrates an application example of the present invention.

In the illumination device, which is installed almost in the same way as the embodiment shown in FIG. It is installed in a position that does not allow transport. Also, the first lamp 5
A delay time is provided between when 3& is lit and the drive system is scanned.

With the illumination device installed in this way, the photosensitive material will not be unnecessarily deteriorated by outside light, and the platen 1
Since the original on 3 is irradiated with light from the back side, if you want to obtain an enlarged copy of a part of the original, that part is placed on a predetermined stage as shown in Figure 5.
You can check whether it is true or not.

(Effects of the Invention) As described above, in the illumination device of the present invention, since the illumination means and the imaging optical system scan separately and independently, the load on the drive system is reduced and high-speed scanning is possible.

Furthermore, since high-speed scanning can be performed without increasing the output of the drive system, a suitable image can be formed without causing vibration in the copying machine body.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating the illumination device of a conventional slit exposure MS child copying machine, FIG. 2 is a configuration diagram of an illumination device according to an embodiment of the present invention, and FIG. 3 is a configuration diagram of an illumination device according to another embodiment. 4 is a configuration diagram showing an application example of the present invention, and FIG. 5 is a top view of the platen of FIG. 4. Symbols in the figure 10.40.53 - lamp 11.41 - lamp carriage 12... original 13... platen 14 - guide rail 15.28.44 - cable 16.29.47 - servo motor 17.30 .42-Capstan Pulley 18.31.4
3. , idler pulley 20-photosensitive drum 21...full rate mirror 22...8-7 rate mirror 26...lens 24...4th mirror 25...full rate mirror 26...half rate carryge 27...8- 7 rate pulley 30.50.51...Position sensor 45.49-.Clutch 46..Gear 47..Paper size

Claims (1)

[Claims] An illumination device for an electronic copying machine that side-lights an electrophotographic photoreceptor using a moving light source and an imaging optical system to form a slit image, comprising an illumination means having the light source, and a plurality of mirrors and lenses. An electronic compound comprising an optical system and a driving means for driving the illumination means and the imaging optical system, wherein the illumination means and the imaging optical system are scanned separately and independently.