JPS60221775A - Illuminating device of color copying machine - Google Patents

Abstract

PURPOSE:To make an output of each light source small, to reduce power consumption, to make a titled device light in weight, and to secure its scanning speed by reciprocating independently plural light sources of monochromatic light once, respectively to execute an exposure and moving back the light sources collectively after all the exposures have been ended. CONSTITUTION:Three fluorescent lamps 1, 2 and 3 having monochromatic light sources of red, green and blue are installed to the respective independent lamp carriages 4, and connected to a servo-motor 13 through clutches 10-12. In this state, the lamps 1, 2 and 3 are driven successively, reciprocated once independently, respectively, and an exposing scan of monochromatic light is executed. When all exposing cycles are completed, the carriages 4, 21 and 22 are moved back collectively to the home position. Therefore, an output of each light source is made small and power consumption can be reduced as compared with that which resolves light of one white fluorescent lamp by a filter. Also, the weight of the device can be made light, therefore, a sufficient scanning speed can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an illumination device for a color copying machine comprising a slit optical system fixed to a document table, and particularly to an illumination device with low power consumption.

(Prior art) Conventionally, so-called xerography has been used to separate red, green, and blue colors using color separation filters, and to repeat the process of charging, exposing, developing, and transferring an electrophotographic photoreceptor for each color resolution. A color copying machine based on this method is known.

Compared to black and white copying machines using the same system, color copying machines tend to lack illuminance because they can only use the light output of the exposure lamp. Ta.

Also, if the power consumption of a single-color red, green, or blue fluorescent lamp is 100 when viewed from the input side, it is 300 to 400 when a white fluorescent lamp is used, and 400 when a halogen lamp is used.
It requires 3 to 5 times the power of monochromatic light, for example 500 to 500, and the power required to lower the potential of the sensitive material varies depending on the light source used.

Therefore, if a color copying machine were designed to have the same copy speed as a black and white copying machine, it would consume more power and require special electrical work to install the machine. Furthermore, if the power consumption is reduced and the copy speed is slowed down, color copying machines repeatedly perform three transfers, so they only have the productivity of T of black and white copying machines, which reduces copy productivity and limits the practical range. It will come off.

(Objective of the Invention) An object of the present invention is to provide an illumination device that can obtain a sufficient cohering speed with low power consumption in a color copying machine having a fixed slit optical system with an original bucket stand.

(Structure of the Invention) That is, the above object of the present invention is to provide an illumination device for a color copying machine that repeatedly exposes a photoreceptor to light using a moving light source to form a slit image, which includes a plurality of light sources each emitting different monochromatic light; It has a driving means for independently driving a plurality of light sources, and an imaging optical system that reciprocates independently of the plurality of light sources, and the imaging optical system is configured to act on each light source for each light source that sequentially moves back and forth. This is achieved by an illumination device for a color copying machine characterized in that the light source moves back and forth once each time, and after the exposure is completed, the light source is moved back all at once.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings. In this embodiment, a case will be described in which a color image is obtained by repeating the copying process three times using exposure sources of three colors: red, green, and blue.

FIG. 1 is a schematic diagram showing an illumination device for a color copying machine according to the present invention. On the back side of the platen 26 on which a document (not shown) is placed, there are three fluorescent lamps (with red, green, and blue monochromatic light sources that can be moved along the platen 26 to illuminate the surface of the document). (hereinafter simply referred to as a lamp in this specification) 1y213 is provided. Each lamp 1, 2.
3 are installed on independently movable lamp carriers 4, and each carriage is aligned on the same plane and scanned in the order of exposure in the color process.

Further, each lamp kitriage 4 is provided with a flapper 5 for condensing light onto the surface of the document.

According to FIG. 2, each lamp 1, 2 . :l') [An imaging optical system that moves independently of the rotor stage and lamp drive system will be described. Each lamp carriage 4 is held by a cable 7, 8, 9 stretched between a cab tongue pulley 5, an eye pulley 6, and a pulley 6 disposed respectively. 26 (left-right direction in the figure; hereinafter, in this specification, movement from left to right will be referred to as forward movement, and movement from right to left will be referred to as backward movement). That is, each carburetor tongue pulley 5 is connected to each clutch 10 to which rotational force is transmitted independently.
, 11, 12, and a drive shaft 14 directly connected to one servo motor 13 through a gear 15.

Further, this illumination device has a one-dimensional imaging optical system that is driven independently of the above-mentioned lamp drive system and whose drive is controlled by the lamp drive system.

This imaging optical system includes a moving full rate mirror 16, a pair of half rate mirrors 17, and a fixed lens 1.
8 and a fourth mirror 19, each lamp 1
, 2.3, the projected light from the document surface is conveyed through each of the above-mentioned optical systems to form an electrostatic latent image on the rotating photosensitive drum 20 surface.

The full rate mirror 16 is a full rate carry 21
Furthermore, the half-rate mirrors 17 are attached to the half-rate carriages 22, respectively, and both the carriages 2
1.22 is held at a distance from each other by a cable 23 stretched between a capsulator pulley 5 and an eye pulley 6 provided in the same manner as the lamp driving means described above, and is reciprocated via a clutch 24. possible. In other words, the full rate carry 21 is attached so as to grip the cable 23, and the half rate carry 22 has the cable 23 wound around it.
It is supported by a half-rate pulley 25 that rolls as a result of the movement of. Further, the half-rate pulley 25 is supported by a stretched cable 27, and is provided so that its transfer can be carried out suitably. Further, in the driving means of each lamp 1, 2.3 and the imaging optical system, sensors 28, 29 for detecting the home position in proximity to the moving lamp carriage 4 and full rate carriage 21 are installed at respective predetermined positions. It is provided.

Next, the present invention will be explained according to the exposure process with reference to the sequence chart of FIG.

When the first lamp 3 to be scanned is lit and the clutch 12 is connected, the rotation of the servo motor 13, which rotates in the forward direction, is transmitted to the carburetor tongue pulley 5 via the gear 15, which moves the cable 9 to move the predetermined lamp. Move Carriage 4 forward. When the lamp carriage 4 begins to move forward and passes a predetermined sensor 28, the imaging optical system begins to be driven by a signal from the sensor 28. That is, the senna 2
A clutch 24 that moves the imaging optical system is actuated by the detection signal from the lamp carriage 8, and the full rate mirror 21 and the half rate mirror 22 are moved forward in synchronization with the lamp carriage 4. At this time, the lamp 3 is turned on to perform image exposure,
The other lamps 1 and 2 are placed in the off state at the home position. When a predetermined period of time has elapsed and the lamp 3 completes scanning the image and reaches the end in the forward direction, the lamp 3 turns off, the clutch 12 disengages, and the lamp carriage 4
to stop. On the other hand, the clutch 24 of the imaging optical system remains connected, and the servo motor 13 reverses to move the full rate carriage 21 and the half rate carriage 22 back. When the full rate carry 21 and the half rate carry 22 return to their home positions, the full rate carry 21 comes over the sensor 29, causing the servo motor 13 to rotate forward again. Next, when the clutch 11 of the lamp 2 scanned second is activated, the lamp 2
repeats the above cycle while being lit. Finally the third
When the second lamp 1 repeats the same cycle and completes image scanning, lamp 1 turns off, but all the lamp drive system clutches 10, 11, 12 and the imaging optical system clutch 24 are connected, and at the same time The servo motor 13 is reversed to return all lamp carriages 4, full rate carriage 21 and half rate carriage 22 to their home positions to complete the entire exposure cycle.

When copying multiple sheets, this can be achieved by repeating the above cycle. Furthermore, when it is desired to make a copy by exposing only one color, it is also possible to configure the apparatus so that only a predetermined lamp scans.

Note that the relative positional deviation that occurs between the lamps and the imaging optical system after each of the lamps 1, 2, and 3 passes through the sensor 28 until the imaging optical system starts scanning is controlled by the use of the servo motor 13. It is very small. Moreover, this relative positional shift does not become a factor that causes insufficient illuminance.

As shown in FIG. 4, if each lamp is 31°32.3
3 are fixed to the same carriage 30, and configured so that only the relative position with respect to the mirror 34 is shifted, the carriage 30
0 Weight becomes heavy, and vibrations generated when reciprocating at high speed cannot be ignored, causing color shift. However, in the illumination system according to the present invention, the weight of the carriage being scanned at each point in time is the same as that of a conventional black and white copying machine, and only the weight increases during the return movement when the third exposure cycle is performed.

However, the vibration to the copying machine that occurs at this time can be solved by slowing down the return speed of the carriage, or by delaying the start of the next copy until the vibration (b') subsides.Usually , it is possible to provide such a period of time before the next copy starts.

Next, a modification of the present invention is illustrated in FIG.

Each lamp carry (50, 51, 52) carrying red, green, and blue lamps 63, 64, and 65 is provided so as to be able to reciprocate on a common guide rod (53). A bushing 54 with a part of the imaging optics engages with the lamp carriage 50, 51, 52, and
0, 51, and 5'2 can be scanned sequentially one by one. That is, the bushing 54 has claws 56 and 57 at both ends, which are projected by the tension spring 55 and are sunk in by the action of the solenoids A and B.
51.52 is locked and scanned with one claw 56. lamp·
When all the carriages 50, 51, 52 are scanned, the other claw 57 scans all the lamp carriages 50, 51, 52.
It has a configuration that pulls back to the home position all at once. With this device, the drive system is simplified and there is no misalignment between the lamp and the imaging optical system. Below, red, green, and blue lamps 63
, 64.

65 is sequentially scanned to obtain one color copy, the process will be explained with reference to the sequence chart of FIG. The button 54, which is stopped on the sensor 61, starts scanning at the same time as the red lamp 63 lights up and the motor 62 rotates forward. When the solenoid B passes the sensor 59 in a conductive state, the current is cut off and the claw 56 protrudes, and the lamp carriage 5 (1') of the red lamp is scanned.The button 54 moves back after the reference clock tl, and at the same time the red lamp 63 is turned on. Turn off the light and go green/Turn on the Pro 4 and prepare for the next cycle. Butsusha 5
After the motor 4 returns to the home position, it passes the sensor 60 through the same process, and the motor 62 starts rotating normally again, causing the green lamp 64 to scan. Finally, when the bushing 54 passes the sensor 61 and finishes scanning the blue lamp 65, it activates the solenoid A to protrude the claw 57, and simultaneously returns each lamp carriage 50, 51, 52 to its home position to complete the exposure cycle. complete. In addition, red
It goes without saying that the scanning order of the green and blue lamps can be arbitrarily set depending on the design.

(Effects of the Invention) As described above, the illumination device of the present invention uses three monochromatic light sources of red, green, and blue to vaguely scan the document and expose the image. Compared to the case where three colors are separated using a filter, the output of each light source is small, and the configuration can be configured to save power. Further, since an expensive dichroic filter for color separation is not required, it is advantageous in manufacturing. In addition, each light source is used independently for scanning, and the view of the driving body equipped with each light source can be made lighter, and the occurrence of vibrations in the main body of the machine, which can cause color misregistration, can be suppressed. Further, since it is light in weight, it has the advantage of being able to perform high-speed scanning.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an illumination device according to an embodiment of the present invention, FIG. 2 is a diagram explaining the lamp driving means and imaging optical system of FIG. 1, and FIG. 3 is a diagram illustrating the lamp driving means and imaging optical system shown in FIG. FIG. 4 is a diagram explaining a conventional example; FIG. 5 is a diagram showing a modification of the present invention; FIG. 6 is a control sequence chart of a modification of FIG. 5. Symbols in the figure 1.2.3...Lamp, 4,50,51.52...
Lamp carryage, 5...cab's tongue pulley,
6...Guide 8 U-Boo 9,? , 8, 9.23...
Cable, 10, 11, 12.24...Clutch, 1
3゜62... Servo motor, 14... Drive shaft, 15
...Gear, 16...Full rate mirror, 17...
Half rate mirror, 18... Lens, 19... Fourth mirror, 20... Photosensitive drum 9, 21... Full rate mirror, 22... Half rate pulley, 2
5...Half rate pulley, 28,2'l, 59,6
0,61...Sensor, 53...Guide rod, 54
...butsusha, 55... tension spring, 56, 57.
...Claw, 63...Red/Pu, 64...Green lamp, 6
5... Blue lamp agent Patent attorney (8107) Kiyotaka Sasaki (and 3 others) Figure 1 Figure 6 Figure 2 Figure 3 Clara now 1゜

Claims (1)

[Claims] An illumination device for a color copying machine that repeatedly exposes a photoreceptor to a moving light source to form a slit image, comprising: a plurality of light sources each emitting a different monochromatic light; a driving means for independently driving each of the plurality of light sources; It has a plurality of light sources and an imaging optical system that moves back and forth independently, and the imaging optical system moves back and forth once each time accompanying each light source for each light source that moves back and forth in sequence, and after the completion of exposure, An illumination device for a color copying machine, characterized in that the light source moves back and forth all at once.