JPS6086564A - Electronic copying machine - Google Patents

Abstract

PURPOSE:To prevent an excessive rise of a temperature of a member in the vicinity of an exposing lamp by adjusting a light putting-out time of the exposing lamp at the time of a continuous copying in accordance with a variation of an electric power supplied to the exposing lamp and the number of copy sheets. CONSTITUTION:In accordance with a variation of an electric power supplied to an exposing lamp 5a by an electric power setting switch 18, and a counting value of the number of copy sheets based on a copying paper detecting output through a phototransistor 15b opposed to a light emitting element, a microcomputer 22 determines a light putting-out time of the lamp 5a. By a control signal corresponding to this light putting-put time, a light putting-out time at the time of a continuous copying of the lamp 5a is adjusted through a transistor 24, a photocoupler 25, a triode AC switch 26, etc. As a result, an excessive rise of a temperature of a member of a contact glass, etc. in the vicinity of the exposing lamp caused at the time of a continuous copying can be prevented.

Description

[Detailed description of the invention] Technical field The present invention relates to an electronic copying machine.

2. Description of the Related Art As a prior art electronic copying machine, one is known in which the power supplied to an exposure lamp of an exposure device can be adjusted in multiple stages.

However, this electronic copying machine has a drawback in that when a large amount of power is supplied to the exposure lamp of the exposure device, the temperature of members such as contact glass near the exposure lamp increases too much during continuous copying.

Purpose An object of the present invention is to adjust the extinguishing time of the exposure lamp during continuous copying in response to changes in the power supplied to the exposure lamp and the number of copies, so that members such as contact glass near the exposure lamp can be An object of the present invention is to provide an electronic copying machine that can prevent the temperature from rising too much.

Configuration Next, the configuration of the present invention will be explained based on illustrated embodiments.

The present invention makes the lighting time of the exposure lamp constant, or
In an electronic copying machine that can set a predetermined time according to the copying magnification and also change the exposure lamp turn-off time during continuous copying, □As shown in Figure 1, the power supplied to the exposure lamp is a supply power determination means B for determining the magnitude of the supply power set by the supply power setting means AK; and a copy number counter C for counting the number of copies during continuous copying; The number of copies determined by the number of copies determined by the number of copies counted by the number of copies counter C, and the turn-off time of the exposure lamp during continuous copying based on the determination results of the power supply determination means B and the number of copies determined. A specific example of the present invention will be described with reference to FIGS. 2 to 6, which includes a light-off time determining means E for determining the light-off time.

FIG. 2 schematically shows an example of an electronic copying machine according to the present invention.

In FIG. 2, reference numeral 1 indicates a contact glass. A document 2 is placed on the contact glass 1 . An original pressing plate 4 for pressing the original 2 onto the contact glass IlIc is provided on the exterior plate 3 near the contact glass l so as to be openable and closable.

An exposure device 5 is arranged below the contact lath 1. A drum-shaped photoreceptor 6 is arranged below the exposure device 5 . The photoreceptor 6 is rotated at a predetermined circumferential speed in the direction of arrow a during copying.

Around the photoconductor 6, there is a charging device 7, a developing device 8, a transfer device 9, a transfer paper supply device 1o, a fixing device 11, a transfer paper conveyance device 12, a cleaning device 13, and a static eliminator 1.
4 etc. are arranged at predetermined positions.

The exposure device 5 includes an exposure lamp 5a that illuminates the original 2;
Riff L/kuta 5b, first mirror 5c, second mirror 5d,
Zoom lens 5e, third mirror 5-5f, and fourth mirror 5
It consists of g. By moving the exposure lamp 5a, reflector 5b and first mirror 5c in the direction of the arrow, and moving the second mirror 5d in the same direction as these at a speed ratio of 2:1, Q, (jfj, Slit-shaped image light from @2 is irradiated onto the photoreceptor 6. The exposure lamp 5a
, the speed of the reflector 5b and the first mirror 5c in the direction indicated by the arrow is determined at a predetermined ratio to the peripheral speed of the photoreceptor 6 according to the copying magnification, and the peripheral speed of the photoreceptor 6 is constant. The lighting time of the exposure lamp 5a is set to a predetermined time depending on the copying magnification.

After the photoreceptor 6 is irradiated with image light from the entire surface of the document 2, the exposure lamp 5a stops in an extinguished state, moves in the direction opposite to the direction indicated by the arrow, and returns to the standby position tc.

The light emitting element 15 of the paper detection means 15 is arranged so as to sandwich the feeding path of the transfer paper fed by the transfer paper supply device 110.
a and a phototransistor 15b are arranged. An operation panel 16 is provided on the upper surface of the exterior plate 3. As shown in FIG. 3, this operation panel 16 includes a magnification setting switch 17 for setting the copy magnification, a power setting switch 18 for setting the power supplied to the exposure lamp 5a, and a number of copies. A number-of-copies setting switch 19, a start switch 20, a stop switch 21, etc. are provided for this purpose.

As shown in FIGS. 3 and 4, the magnification setting switch 17 includes, for example, four key switches. Information indicating which of the magnification setting switches 17 is turned on is input to the microcomputer 220 (yJj-)K. The power setting switch 18 includes, for example, eight key switches. Information on which of these power setting switches 18 is turned on is given to the input port of the microcomputer 22. The number-of-copies setting switch 19 consists of a 1o key switch. Information about which one of these copy number setting switches 19 is turned on or in what order a plurality of copy number setting switches 19 are turned on is provided to the input port of the microcomputer 22. It will be done.

Further, information indicating that the start switch 2o and stop switch 21 are turned on is provided to the input port of the microcomputer 220.

The collector of the phototransistor 15b of the paper detection means 15 and the terminal 2 to which a predetermined voltage is applied by the DC power supply.
A resistor r1 is connected between 3 and 3. The connection point between the collector of the phototransistor 15b and the resistor r1 is connected to the input port of the microphone computer 22.

When the transfer paper passes between the light emitting element 15a of the paper detection means 150 and the phototransistor 15b, the phototransistor 15b detects this, and this detection signal is sent to the copy number counter of the microcomputer 22 via the input port. The copy number counter counts the number of transfer sheets fed by the transfer paper supply device 10, that is, the number of copies.

The output port of the upper E microcomputer 22 is resistor r2.
Transistor 240 is connected to the base via.

A light emitting diode 25a of a 7-opto coupler 25 is connected to the collector of this transistor 24. The III source lamp 5a and the triac 26 are connected in series to an AC power source 27.

A DC power supply 28 is connected between the power supply terminal of the trybook 26 and the emitter of the phototransistor 25b of the photocoupler 25. The phototransistor 25b
The collector of is connected to the gate terminal of the triac 26 via a resistor r3. The above triac 26 has
When the phototransistor 25b is in the ON state, the DC power supply 2
A gate current flows from the phototransistor 8 through the phototransistor 25b.

During the lighting time of the exposure lamp 5a, a pulsed output signal consisting of an ON signal and an OFF signal is applied from the output port of the microcomputer 22 to the pace of the transistor 24. When an ON signal is applied from the output port of the microcomputer 22 to the base of the transistor 24, the transistor 24 is turned on, current flows through the light emitting diode 258 of the photocoupler 25, the light emitting diode 25a emits light, and the phototransistor 25b is activated. When turned on, a gate current flows from the DC power supply 28 to the triac 26, and the triac 26 is turned on. Therefore, current is supplied from the AC power supply 27 to the exposure lamp 5a, and the exposure lamp 5a lights up.◎ The above power setting switch 1B The microcomputer 22 turns on the exposure lamp 5 in response to an ON signal from each different one.
By changing the phase of the output signal from the output boat during the lighting time of a, the energization ratio of the try book 260 is changed, and the magnitude of the power supplied to the exposure lamp 5a is changed in multiple stages.

Note that the input section of the supply power setting means A may be the peak of a circuit having a power setting switch 18, or as shown in FIG.
A variable resistor r4 and a resistor rs, whose resistance value can be changed by operating the knob 30 with your fingers, are connected in series between the terminal 29 to which a predetermined voltage is applied by the DC power supply and the ground. The voltage at the connection point between the resistor r4 and the resistor rs is transmitted to the microcomputer 2 via the A/D conversion circuit 31.
Knob 3 that is given to 2 and changes the resistance value of variable resistor r4
0 may be configured to provide the microcomputer 22 with information for setting the power supplied to the exposure lamp 5a. Explain an example.

The start switch 20 is turned on, one of the magnification setting switches 17 is turned on, one of the power setting switches 1B is turned on, and one or more of the number-of-copies setting switches 19 are turned on. Then, the operation of the electronic copying machine is started according to the procedure of the program stored in the ROM of the microcomputer 22 and shown in 70-K in FIG.

First, as shown in FIG. 6, in a step, the lighting time of the exposure lamp 5a is set to a predetermined time based on information from the magnification setting switch 17. When changing the copying magnification by turning on one of the magnification setting switches 17 in the step, an output signal is given from the output port of the microcomputer 22 to the optical member driving means (not shown), and the exposure device 5 The position and focal length of the zoom lens 5e and the position of the third mirror 5f are changed.

Next, in step (2), the magnitude of the power to be supplied to the exposure lamp 5a is set based on the information from the power setting switch 18, and the set power value P is stored in the RAM.

Next, in step (2), it is determined based on the information from the copy number setting switch 19 whether or not the set copy number N is 2 or more, that is, whether N≧2.

If it is determined in step ■ that N≧2, step ■
It is determined whether or not M≦M1 by comparing the number M of the Kohi one number counter of the micro combinator 22 with the reference number M1 stored in the ROM.

If it is determined in step ■ that M≦Ml is not true, then in step ■ the count value M and the reference sheet value M2 stored in the ROMK are determined.
It is determined whether M≦M2 by comparing (M2>Ml).

If it is determined in step (2) that M≦M1, then in step (2) it is determined whether or not P≦P1 by comparing the set power value P with the reference power value PI stored in the ROM.

If it is determined in step ■ that P≦P1 is not satisfied, then in step ■ the set power value P is compared with a reference power value P2 (P2>Pl) stored in the ROMK to determine whether P≦P2. Ru.

When it is determined in step (2) that M≦M2, it is determined in step (2) whether or not P≦P1.

If it is determined in step (2) that P≦P1 is not satisfied, then in step (2) it is determined whether or not P≦P2.

When it is determined in step (2) that M≦M2 is not satisfied, it is determined in step [phase] whether P≦P1.

When it is determined in step [phase] that P≦Pl is not satisfied, it is determined in step @ whether P≦P2.

If it is determined in step (2) that P≦P1, then in step @, it is determined that 1==il, where the extinguishing time of the exposure lamp 5a during continuous copying is defined as 萱.

If it is determined that P≦P2 in step ■, and that P≦P1 in step ■, step 0
It is determined that t=tz(tz)tx).

If it is determined that P≦P2 is not established in step ≦P≦P2 in step ■, and that P≦Pi is determined in step [stock], then t:ta is determined in step 0.
(ta)t2) is determined.

If it is determined in step ■ that P≦P2 is not true, and if it is determined that P≦P2 in step @, it is determined that t=t4 (t4) ta) in step [phase].

If it is determined in step @ that P≦P2 is not satisfied, then t=t5(ta)t4) is determined in step [phase].

Next, in step O, the image of the document 2 is copied. Next, in step [phase], it is determined whether or not copying is complete. If it is determined in step [phase] that copying has not been completed, steps 1 to 0 are executed again. When it is determined in step [phase] that copying is complete, the copying operation is stopped.

In addition, the above-mentioned count value M is compared with a reference sheet value of 3 or more to determine the size, and the set power value P is compared with a reference power value of 3 or more to determine the size, and based on these determination results. The extinguishing time of the exposure lamp 5a during continuous copying may be determined in multiple stages.

Furthermore, the present invention can be applied to an electronic copying machine that does not have a means for changing the copying magnification, that is, an electronic copying machine whose exposure lamp lighting time is constant.

Effects The electronic copying machine of the present invention adjusts the extinguishing time of the exposure lamp during continuous copying in response to changes in the power supplied to the exposure lamp and the number of copies to be made, thereby reducing damage to contact glass, etc. near the exposure lamp. It is possible to prevent the temperature of the member from rising too much.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a partially cutaway front view showing an outline of the configuration of an electronic copying machine as an embodiment of the present invention, and FIG. 3 is an operation panel of the same electronic copying machine. FIG. 4 is an electric circuit diagram showing an electric circuit according to an embodiment of the present invention, FIG. 5 is an electric circuit diagram showing main parts of another embodiment of the same electric circuit, and FIG. is a flowchart showing an example of a program for operating the electronic copying machine of the present invention. 5...Eleven device, 5a...Exposure lamp, 6...
Photoreceptor, 18...Power setting switch, 15...Paper detection means, 15a...Light emitting element, 15b...Phototransistor, 22...Microcomputer

Claims (1)

[Claims] j! In an electronic copier, the lighting time of the original lamp can be fixed or set to a predetermined time depending on the copying magnification, and the exposure lamp turn-off time can be changed during continuous copying. a supply power setting means for setting supply power; a supply power determination means for determining the magnitude of the supply power set by the supply power setting means; a copy number counter for counting the number of copies during continuous copying; Copy number determining means for determining the magnitude of the count value of the copy number counter; and light-off time determination for determining the extinguishing time of the exposure lamp during continuous copying based on the determination results of the power supply determining means and the copy number determining means. An electronic copying machine characterized by comprising means.