JPS638018B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying apparatus having a plurality of paper feed systems, and more specifically, a copying apparatus having a plurality of paper feed systems and a copying apparatus provided for each paper feed in order to feed out the transfer paper in the paper feed part. and a second paper feed roller that conveys the transfer paper sent out from the feeding unit and waiting at a predetermined stop position to the next stage by the first paper feed roller. The present invention relates to a copying apparatus in which the lengths of transfer paper transport paths formed between the paper feed section and the second paper feed roller are different.

The basic structure of a copying apparatus having a plurality of paper feeding systems and using an original table moving type is shown in FIG.
In FIG. 1, reference numeral 1 denotes a document placement table; 2, a document placement surface made of transparent glass provided above the document placement table 1 and below a flannel cover (not shown); and 3, It is a manuscript. The document mounting table 1 is capable of reciprocating movement (in the direction of the arrow in the figure), and its moving distance can be changed depending on the size of transfer paper to be used. The movement distance regulation signal is obtained by a plurality of microswitches (not shown) installed in the main body of the apparatus in association with the paper feed cassette 12, which will be described later. Reference numeral 4 denotes an exposure lamp consisting of a fluorescent lamp provided below the document table 1. The exposure lamp 4 is integrated with the reflector plate 5 by a lamp holding member (not shown). Further, the inner surface of the reflecting plate 5 is shaped so that the light emitted from the exposure lamp 4 can be focused onto the document placement surface 2. A slit 51 is bored in a protruding portion of the reflecting plate 5 at the center between the exposure lamps 4. A first mirror 6 is located directly below the slit 51 and is set at a predetermined inclination with respect to the optical axis. 7 is a lens, and 8 is a second mirror. The optical system described above guides the reflected light from the document 3 caused by the light emission of the exposure lamp 4 onto the photosensitive drum 9. 9 is a photosensitive drum constructed by depositing a photoconductive insulating layer made of selenium on the surface of a hollow aluminum cylinder, and is directly connected to a main motor (not shown) and rotates in the direction of the arrow when operated. ing. 10 is a charging device powered by a DC power source, and 11 is a magnetic brush developing device. The charging device 10 has a function of uniformly charging the surface of the photosensitive drum 9, and the electrical charge on the photosensitive drum 9 is appropriately eliminated or reduced by the reflected light from the original 3 caused by the light emission of the exposure lamp 4. Then, the charge pattern is sequentially converted into a charge pattern corresponding to the original document 3, and the charge pattern is converted into a visible image (toner image) by the magnetic brush developing device 11. 12 is a paper feed cassette forming a paper feed section;
13 is a sheet receiving plate, 14 is a pressure bonding plate, 15 is a transfer paper, and 16 is a first paper feeding roller. The transfer paper 15 is placed on the sheet receiving plate 13 and transferred to the paper feed cassette 12.
It is stored in. When the paper feed cassette 12 is installed in the main body of the apparatus, the sheet receiving plate 13 is pushed up by the pressure bonding plate 14, and the transfer paper 15 on the uppermost surface is placed in the first position.
It is designed to come into contact with the paper feed roller 16. 1
7 is a guide member, and 18 is a second paper feed roller.
The leading edge of the transfer paper 15 sent out by the first paper feed roller 16 comes into contact with the second paper feed roller 18, which is still in a stopped state at the time of feeding, and is stopped. Reference numeral 19 indicates a transfer device having a function of transferring the toner image carried on the photosensitive drum onto a transfer paper, and reference numeral 20 indicates a transfer device for peeling off the transfer paper, which moves while being electrostatically attracted to the photosensitive drum 9, from the photosensitive drum 9 after transfer. This is a static eliminator for separation that is connected to an AC power source. Reference numeral 21 denotes a conveyance device consisting of a suction box, a belt, etc., which sucks the transfer paper after passing through the transfer process onto the belt and conveys it to the next stage. 22 is a roller type fixing device, 23
is a tray. The fixing device 22 heats the transfer paper carrying the toner image by the urging of the transfer device 19, and melts and fixes the toner onto the transfer paper. A cleaning device 25 removes toner remaining on the photosensitive drum after transfer.

Most of the process operations in a copying machine with such a configuration are performed by a microcomputer (not shown).
It has come to be controlled by That is, signals such as setting the number of copies, copy commands, clearing, etc. are obtained from the operation board consisting of a numeric keypad etc. on the main body of the apparatus, one of several time charts is selected, and the first Paper feed roller 16, second
The paper feed roller 18, photosensitive drum 9, etc. are driven.

By the way, as mentioned above, in the case of a copying apparatus having multiple paper feed systems, the distance from the paper feed cassette 12 to the position where the transfer paper is temporarily stopped (i.e., the distance from the paper feed cassette 12 to the second paper feed roller 18) Distance to the position where the leading edge of the transfer paper comes into contact.In this specification,
The length of the transport path of the transfer paper (referred to as the length of the transport path of the transfer paper) is selected so that it is approximately the same in all paper feeding systems.

On the other hand, recent copying devices are required to be designed to satisfy improvements in functionality and space factor, and it has become difficult to equalize the length of transfer paper transport paths in each paper feeding system. . However, the demand for shortening the feeding operation time in multiple paper feeding systems has become quite strong.

The present invention was made in response to this demand, and its main purpose is to provide a copying apparatus that does not waste time during feeding operations in multiple paper feeding systems and does not apply impact to transfer paper. It is in. The basic structure of the present invention to achieve this objective is to change the feeding speed of the transfer paper depending on the length of the transfer path of the transfer paper, and to change the feeding speed according to the change in the feeding speed.
The present invention is characterized in that the distance between the transfer paper and the second paper feed roller at the end of the feeding operation is changed.

The present invention will be explained in detail below using the drawings.

The copying apparatus according to the present invention is mainly different from the apparatus shown in FIG. 1 in its paper feeding system. ). FIG. 2 is a configuration explanatory diagram showing an embodiment of a paper feeding system of a copying apparatus according to the present invention. In FIG. 2, the paper feed system includes a paper feed cassette 12A and a first paper feed roller 16.
A, a paper feeding system (hereinafter referred to as paper feeding system A) consisting of guide members 17A and 17', and a paper feeding cassette 12.
B, a paper feeding system consisting of the first paper feeding roller 16B, guide members 17B and 17' (hereinafter referred to as paper feeding system B)
, paper feed cassette 12C, first paper feed roller 16
C, and a paper feeding system (hereinafter referred to as paper feeding system C) consisting of guide members 17C and 17'.
The transport trajectory of paper feed systems A, B, and C is the member 1.
7A, 17B, and 17C merge at the ends, and the area from this merging point X to the second paper feed roller 18 forms a common trajectory by the guide member 17'. The configuration of each paper feed cassette 12A, 12B, 12C is as follows:
As in the figure, transfer papers 15A, 15B, and 15C of different sizes or paper qualities are stored. The lengths of the transport trajectories of each paper feeding system A, B, and C are la, lb, and lc, and their magnitudes are such that la>lb>lc. Further, 24 is a light emitting element 24a and a light receiving element 2.
4b, the starting point of the common trajectory, i.e.
This is for detecting the transfer paper passing through the position where all the transfer paper sent out from each paper feed cassette passes. Of course, this sensor 24 may be constructed from a micro switch or the like.

The first paper feed rollers 16A, 16B, or 16C forming each of the above-mentioned paper feed systems A, B, and C are selected by a cassette selection switch provided on the operation board of the main body of the apparatus, and are started by a copy command signal. It is now controlled by a time chart.

Next, the first paper feed rollers 16A, 16B and 16
The control system of C will be explained with reference to the block diagram of FIG. In FIG. 3, 26 is a cassette selection switch, and 27 is a copy command button, both of which are provided on the operation board of the main body of the apparatus.
The cassette selection switch 26 is connected to the feeding roller 16A,
This is a switch for selecting paper feed cassettes 16B and 16C, that is, a switch for selecting paper feed cassettes 12A, 12B, or 12C. When the paper feed cassette 12A is selected by this switch 26, the signal Sa is turned on, when the paper feed cassette 12B is selected, the signal Sb is turned on, and when the paper feed cassette 12C is selected, the signal Sc is turned on. The copy command button 27 generates a signal _S1 which starts the sequence operation of the apparatus. When the signal _S1 from the copy button 27 is turned on, the main motor 31 that drives the photosensitive drum 9 is activated. The sensor 24
As explained in the figure, the transfer paper is at the starting point of the common trajectory
The time when the transfer paper is transferred to
Has the function of generating _S3 . 28 is a control circuit. The control circuit 28 has three timers and counters inside, and a clutch 29 for driving the first paper feed roller.
It has the function of outputting signal _S4 to control. Three timers are provided corresponding to paper feed systems A, B, and C, and the time-up time of each timer is Ta,
Tb and Tc are set. The gate of the start terminal of each timer is controlled by signals Sa, Sb, and Sc. That is, the gates of the timer for time-up time Ta are opened by the signal Sa, the timer for time-up time Tb is opened by the signal Sb, and the timer for time-up time Tc is opened by the signal Sc, and the start signal _S3 from the sensor 24 is opened. It is configured to receive On the other hand, a counter is a rotation angle detection sensor 3 to be described later that detects the rotation angle of the photosensitive drum 9.
It has a function of generating _a count-up signal when the accumulated value after receiving the copy command signal _S1 reaches a predetermined value (count-up). In the sequence operation, consideration is given so that the count-up signal is always issued prior to any time-up signal.

With each function of these counters and timers,
The signal _S4 output from the control circuit 28 is a clutch signal that rises in response to a count-up signal (thereby actuating the clutch 29) and falls in response to a time-up signal (thereby stopping the operation of the clutch 29). It serves as a control signal. 30
is a gearbox. The gearbox 30 has gear trains and clutches corresponding to paper feed systems A, B, and C. The clutch is configured to allow easy selection of each gear train. In addition, the gear train can be switched using a signal.
Sa, Sb, Sc, specifically, the signal
Connect the clutch of paper feed system A by Sa and
The paper feed roller 16A is connected to the paper feed system B by the signal Sb.
connect the clutch of the first paper feed roller 16B,
The clutch of the paper feed system B is connected by the signal Sc to drive the first paper feed rollers 16C, respectively. Reference numeral 32 denotes a rotation angle detection sensor, which has a configuration in which a disk with a slit formed on its peripheral edge is directly connected to the photosensitive drum 9, a photocoupler is installed in the slit, and a pulse signal _S2 is obtained from the photocoupler.

Next, we will discuss the operation of the copying apparatus according to the present invention in the fourth section.
This will be explained with reference to the time chart shown in the figure. Here, the gear ratio of the gear train of the gear box 30 is the first gear ratio.
Feeding speed of paper feed rollers 16A, 16B, 16C
Let's take as an example a case where Va, Vb, and Vc are determined so that the following equation (1) holds true.

la/Va=lb/Vb=lc/Vc (1) First, select the paper cassette 12 you need using the cassette selection switch 26. Assume that the paper feed cassette 12A is thereby selected. Therefore, this selection turns on the output of the signal Sa, and the timer (time-up time) in the control circuit 28 turns on.
The gate of the starting terminal of Ta) is opened, and the clutch of the gear train of paper feed system A is connected (t ₀ ).

Next, when the copy command button 27 is pressed, the signal S ₁
is issued, the main motor 31 is activated, and the photosensitive drum 9 is rotated (t ₁ ). The rotation of the photosensitive drum 9 is detected by the rotation angle detection sensor 32, and a pulse signal _S2 corresponding to the rotation angle is input to the counter of the control circuit 28. An ON signal _S4 is output from the control circuit 28 in response to a count-up signal that is generated when the pulse integrated value reaches a set value (three pulses in the figure). The clutch 29 is actuated by this signal _S4 , drives the first paper feed roller 16A via the gear train of the paper feed system A, and the transfer paper is sent out at the feed speed Va ( _t2 ). The sensor 24 is the starting point X of the common trajectory
Detects the transfer paper passing through and outputs signal _S3 .
The signal _S3 becomes an input to the control circuit 28, and starts the timer (time-up time Ta) of the paper feed system A ( _t3 ). After the time Ta has elapsed, the timer issues a time-up signal, and this signal turns off the output signal _S4 of the control circuit 28, deenergizing the clutch 29.
The drive of the first paper feed roller 16A is stopped (t ₄ ).
Since the transfer paper has inertia in the first paper feed roller 16A, gear train, etc., the transfer paper is fed out for a short time even when the signal _S4 is turned OFF (end of feeding operation), and does not hit the second paper feed roller 18. Stop after touching (between t ₃ and t ₅ ).
This contact is made almost without impact. What is the timer time-up time Ta?
The speed gradient of the transfer paper after the motor 29 is deenergized is determined by the feeding speed Va and the inertial force of the first paper feeding roller 16A (these are unique to the paper feeding system A). In view of this, the speed of the transfer paper is determined by the time determined in relation to the transfer paper passage detection position (in this embodiment, the starting point X of the common trajectory) and the post-detection transfer distances Va and Ta, This is because it is selected so that it becomes sufficiently small just before 18. After the transfer paper comes into contact with the second paper feed roller 18 and stops, the original table 1 starts to move in response to a signal from the microcomputer, and after moving a certain distance, the document table 1 starts moving. The second paper feed roller is driven, and the transfer paper is conveyed toward the photosensitive drum 9 (t ₄ ).

The above operations are similarly performed when the paper feed cassette 12B or 12C is selected by the cassette selection switch 26. That is, it operates similarly for the signal SbSc.

Here, the relationship among the time-up times Ta, Tb, and Tc will be explained. As already explained, the paper feeding speeds Va, Vb, and Vc are set so that Va>Vb>Vc due to the difference in the length of each paper feeding path, but due to the difference in speed, the clutch 29 The time and distance from when the transfer paper stops until the transfer paper stops also differs. For this reason, it is necessary to ensure that the paper that reaches the second paper feed roller 18 and stops is in the same state regardless of the difference in paper feed path. For this purpose, the control circuit 28 sets the time-up time so that Ta<Tb<Tc.
Set the timer within.

FIG. 5 is a configuration explanatory diagram showing another embodiment of the present invention. In this embodiment, sensors 33A, 33B, 3 each consisting of a micro switch are provided on each path of the transfer paper.
3C, and from the sensor 33A to the second paper feed roller 1
8, the length from the sensor 33B to the second paper feed roller 18, and the length from the sensor 33C to the second paper feed roller 18. By doing this, the time-up time Ta,
There is no need to make Tb and Tc different as described above.

In this way, according to the copying apparatus having the above configuration, the longest transfer trajectory la can be achieved without giving any impact to the transfer paper.
Transfer trajectory that minimizes the feeding operation time of the transfer paper through the LC
The operation time for feeding the transfer paper through the can be shortened.

In the above embodiment, the end position of the transfer sheet feeding and urging operation was determined using the output signal of the sensor 24, etc., but it is also possible to prevent the shock of the transfer sheet by predetermining the driving time of the clutch 29. It can be relaxed. However, as in the above embodiment, the sensor 2
Needless to say, the use of the 4th grade, etc. allows for more accurate position control, and therefore a greater effect can be obtained. Further, the location where the transfer paper is detected by this sensor 24 is not limited to X in the above embodiment. Furthermore, although the explanation has been given by taking as an example the case where formula (1) holds true, it may be configured to increase the feeding speed only for paper feeding systems with particularly large transport trajectories. Further, although the description has been given by taking a copying apparatus of a moving document table type as an example, it is clear that the present invention can also be applied to a copying apparatus of a fixed type.

As described above, according to the copying apparatus according to the present invention, it is possible to shorten the feeding operation time in the paper feeding system without applying an impact to the transfer paper.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the basic configuration of a copying apparatus having a plurality of paper feeding systems, FIG. Fig. 2 is a block diagram of the control system in the apparatus, Fig. 4 is an operation explanatory diagram (time chart) of the apparatus in Fig. 2, and Fig. 5 is a configuration showing another embodiment of the paper feeding system of the copying apparatus according to the present invention. It is an explanatory diagram. 1...Document placement table, 2...Document placement surface, 3...
Original, 4...Exposure lamp, 5...Reflector, 6,8
...Mirror, 7...Lens, 9...Photosensitive drum,
10...Charging device, 11...Developing device, 12,1
2A, 12B, 12C...Paper feed cassette (paper feed section), 13...Sheet receiving plate, 14...Crimping plate,
15...Transfer paper, 16, 16A, 16B, 16C
...First paper feed roller, 17...Guide member, 1
7'...Guide member (common track), 18...Second paper feed roller, 19...Transfer device, 20...Separation static eliminator, 21...Transport device, 22...Fixing device,
23...Tray, 24, 33A, 33B, 33C
...Sensor, 26...Cassette selection switch, 2
7... Copy command button, 28... Control circuit, 29...
...Motor, 31...Main motor, 30...Gearbox, 32...Rotation angle detection sensor.

Claims (1)

[Scope of Claims] 1. A plurality of paper feed units, a first paper feed roller provided for each paper feed unit and selectively used to feed transfer paper from the paper feed units, and the first paper feed roller. a second paper feed roller provided to stop the transfer paper sent out by the roller for a predetermined period of time and convey it to the next stage in conjunction with a copying operation, and the paper feed section;
In a copying apparatus having transfer paper transport tracks of different lengths between the second paper feed roller and the second paper feed roller, the first transfer paper transport track disposed on the longer side of the transfer paper transport track
The drive system is configured so that the feeding speed of the paper feeding roller is faster than the feeding speed of the other first paper feeding roller disposed on the shorter side, and the transfer paper is detected within the range of the transfer trajectory. further, when the first paper feed roller with the longer transfer paper transport path is selected, the other first paper feed roller with the shorter transfer paper feed roller is activated by the transfer paper detection signal of the sensor. 1. A copying apparatus comprising a delay control means for stopping its operation earlier than when the copying apparatus is selected. 2 The number of the sensor for detecting the transfer paper is one, and the sensor is disposed near the starting point of a common track that forms a part of the transfer track.
Copying device as described in section. 3 A plurality of paper feed units, a selectively used first paper feed roller provided for each paper feed unit to feed transfer paper from the paper feed unit, and transfer paper fed out by the first paper feed roller. a second paper feed roller provided to stop the paper for a predetermined period of time and transport the paper to the next stage in conjunction with a copying operation, and the paper feed section;
In a copying apparatus having transfer paper transport tracks of different lengths between the second paper feed roller and the second paper feed roller, the first transfer paper transport track disposed on the longer side of the transfer paper transport track
The drive system is configured so that the paper feeding speed of the paper feeding roller is faster than the feeding speed of the other first paper feeding roller disposed on the shorter side, and the driving system is configured such that the paper feeding speed of the paper feeding roller is faster than the feeding speed of the other first paper feeding roller disposed on the shorter side, and within the specific path range of the transfer paper. Therefore, the longer the transfer trajectory, the more
A dedicated sensor is provided at a position away from the paper feed roller, and further includes a control means that is activated in accordance with a transfer paper detection signal from each of the sensors and stops the operation of the corresponding first paper feed roller after a predetermined time. A copying device characterized by: