JPH0453410B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Field> The present invention relates to an improvement in a copying apparatus that performs copying by reciprocating a document table to perform scanning.

<Prior art and its disadvantages> In a copying machine that performs copying by reciprocating the original table and scanning, it is difficult to move the original table from the home position and replace the developing device or change the developing device. There is a device that replenishes developer.
In addition, the upper surface of the optical transmission body is also moved to clean the front and back surfaces of the document table. After performing such an operation, if the original table is left without being returned to its original position, the next person making a copy will not be able to use it immediately. Also, if you decide to store the document tray or cover it after turning off the power, the document tray is not in its initial position, so the operator must move the document tray and return it to its initial position. It was necessary to perform an operation.

<Object of the Invention> The object of the invention is to provide a copying position in which when the original placing table is not at the initial position, the position is automatically returned to the initial position by turning off the power. It is in.

<Structure and Effects of the Invention> In summary, the present invention includes a position detection means for detecting the position of a document placing table, a means for detecting an instruction to turn off the power, and a means for detecting the position when the instruction to turn off the power is detected. The apparatus is characterized by comprising means for detecting the position of the document placing table in the means, and controlling the document placing table to return to the initial position if the document placing table is not at the initial position, and then turning off the power. shall be.

According to this invention, after moving the original table to replace the developing device, replenish developer, or clean the photoelectric transmitter and the original table, the original table is not returned to its original position. Even if you turn off the power immediately, the document tray will be returned to its initial position and then the power will be turned off, eliminating the hassle of returning the document tray to its initial position and allowing you to use it immediately next time. Can be done. In addition, when storing or covering the document table, the document table has already returned to its initial position, so careless handling may cause excessive external force to be applied to the document table and its driving parts. There will be no more danger.

<Embodiment> FIG. 1 is a front sectional view showing the schematic structure of a copying apparatus which is an embodiment of the present invention.

A photosensitive drum 4 is located approximately in the center of the copying apparatus main body 1.
and a charger 5, a developing device 6, a transfer charger 7, a cleaner 8, and a static eliminator 9 on its outer periphery.
are arranged to constitute a copying process section.
On the upper surface of the copying apparatus main body 1, a document table 2 is constructed of a hard transparent material such as a glass plate. A light source 18 scans the document placed on the document table 2, and the reflected light passes through the light converging body 3 and passes through the photoreceptor drum 4.
The light is distributed on the surface as shown by the dashed line in the figure.
The photosensitive drum 4 rotates in the direction of arrow C in synchronization with the scanning of the document table, and its surface is covered with a charging charger 5.
Unipolar charges are uniformly charged. Photosensitive drum 4 that has passed the position of the charging charger 5
A light beam from the document exposure light source 18 is distributed on the surface of the document to form an electrostatic latent image. Next, a developer charged with a polarity opposite to that of the charger is supplied to the surface of the photoreceptor by the developing device 6, and the electrostatic latent image is visualized. The image visualized by this developer is transferred onto the surface of the paper fed from the paper cassette 11 or 12 at the position of the transfer charger 7.
The paper is guided to a fixing device 15 via a paper conveyance path 14, and after the transferred paper is heated and pressurized to be fixed, it is discharged to a paper discharge tray 16. The surface of the photoreceptor drum 4 that has passed the transfer charger 7 has residual developer removed by a cleaner 8, and is then neutralized by a charge eliminator 9 to be rendered charge-free.

By moving the document table 2 to the position indicated by the broken line in the figure, an opening 10 is formed on the top surface of the copying apparatus main body.
appears. This opening is provided when the developing device 6 is replaced or for replenishing developer by fitting into the developer replenishing port 6a of the developing device.

FIG. 2 shows the relationship between the main body and the document table.

The document table 2 is configured so that a copy document is placed on the top thereof. This document table 2 is at the initial position shown in (1) when it is on standby at the copying position. When the print switch to start copying is operated in this state, it is moved in the A direction and the micro switch indicating the exposure start position (original scanning start position) is pressed.
MSW2 operates at the rear part 20b of the detection plate 20,
The document table 2 stops at that position. The stopping position is as shown in (2). A detection plate 20 for operating the microswitch NSW2 is provided on one side of the moving document table 2, and the detection plate 20 is placed at a position indicating the start of exposure during the moving path.

Here, when the exposure start is executed, the document table 2 is moved to B
direction, the original is scanned, and exposure of the photosensitive drum is started. While the document table 2 is moving, a microswitch MSW1 is activated to synchronize the paper with the rotation of the photosensitive drum and start transporting the paper. The microswitch MSW1 is operated at the front end 20a of the detection plate 20. Further, the microswitch MSW1 is arranged at a position for starting conveyance of the paper along the movement path of the detection plate 20. After the operation of the micro switch MSW1, the document table 2 is further moved in the direction B, and the second detection plate 20c that detects the overrun state restarts the micro switch NSW1, thereby stopping the movement of the document table 2. . This state is shown in (3).

Thereafter, the document table 2 is moved to the initial position (1) and stopped at that position.

As described above, the detection plate 20c is a detection member for preventing overrun, and is also used to detect whether or not the document table 2 is at the initial position (hereinafter also referred to as the home position).

FIG. 3 shows a block diagram of the control section of the copying machine. Overall control is microprocessor
It is controlled by MPU. SW is the various detection switches MSW1, MSW2, MSW3 mentioned above.
and a switch for instructing power on/off, and the MPU performs processing according to the state by determining the state of these various switches.
The DSC is a display control circuit, and drives the display device DIS by writing the content to be displayed from the MPU. I/O is an input/output control circuit,
A signal from the MPU activates the driver DRI of the power relay PR or the driver DR2 of the main mora relay MR. This I/O also drives other drive circuits and inputs other sensors. ROM is a memory that stores the MPU processing program in advance, and RAM is a memory that is used as a working area when executing the program.

FIG. 4 is a circuit diagram relating to various switches and a power supply circuit. AC is a commercial power source of 100 V AC, and a DC power source is obtained by a power transformer and a DC power circuit, and the microprocessor MPU is operated by this DC power source. Microprocessor MPU
are the micro switches MSW1, MSW2,
The MSW 3 is connected to a switch ONSW for instructing power on and a switch OFFSW for instructing power off. PRa is the coil of the power relay, and PRb is the relay contact of the power relay. When the microprocessor MPU drives this power relay, PRb is turned on. Also
MRa is the coil of the main motor relay, MRb is the relay contact of the main motor relay, and when the microprocessor MPU drives MRa,
MRb turns on. If both PRb and MRb are on, the main motor M is driven by the commercial power supply AC. Note that LD1 is another addition that operates together with the main motor, and LD2 is another load that operates when the power relay is in the on state.

With the configuration as described above, the microprocessor performs control according to a control program stored in advance in the ROM. FIG. 5 shows the flowchart.

The microprocessor is normally in a HALT state,
If there is an interrupt such as a key input, the interrupt processing determines the switch that caused the interrupt and performs processing accordingly. Figure (A) shows the procedure. If the operated switch is an off switch (OFFSW), interrupt input is first inhibited at step n10 (hereinafter step ni will simply be referred to as ni), as shown in FIG. This is to prevent interrupts from occurring during the subsequent processing. Micro switch on n11
The MSW3 is determined, but if the document glass is not in the home position, that is, in the position (3) in Figure 2, the MSW3 is off, and if it is off, the document glass is moved to the home position at n12. drive in the direction of the direction. The state of the micro switch MSW3 is determined at n13, and the document glass is driven until it is turned on. When the document glass is at the home position, MSW3 is turned on and the document glass is driven at n14. Stop. In this way, the document table is returned to the home position. If the document glass is already in the home position when the off switch is operated, MSW3 is in the on state, so n11 to n15
Proceed to.

At n15, the coil PRa of the power relay is turned off to cut off the operation of the circuit operated by commercial power as shown in FIG. 4, and at n16, the display state is turned off. In other words, it displays that the power is off, or does not display anything at all. after that
At n17, interrupt prohibition is canceled to enable interrupts and enter the HALT state. By operating the turn-off switch as described above, if the document table is not at the home position at that time, the document table is returned to the home position, and the power is then turned off.

The above example was an example of an off switch operation, but conversely, when an on switch (ONSW) is operated, interrupts are first disabled at n22, and then a micro switch is disabled at n21, as shown in (C) of the same figure. M.S.W.
Determine the state of 3. The processing from n21 to n24 is the same as the processing from steps n11 to n14 described above, and if it is detected that the document glass is not at the home position, the document glass is driven and returned to the home position, and then
Perform the process to stop it. Thereafter, at n25, the coil PRa of the power relay is driven to turn on the power relay. As a result, the circuit powered by the commercial power supply AC starts operating as shown in FIG. At n26, a display is made to indicate that the power is on, and at n27, the interrupt inhibited state is canceled to enable interrupts, and at n28, the fixing device and others are warmed up. When the warming-up is completed, a READY display is displayed at n29 indicating that copying operation is possible. By enabling an interrupt before the start of warming-up, key input can be accepted even during warming-up.

As described above, when the document table is not at the home position, by turning on or off the power switch, the document table is first returned to the home position, and then the power is turned on or off.

In the embodiment, power is always applied to the control unit consisting of a microprocessor, etc., but the power is turned on at the same time as the AC power is turned on and off, except for the circuit that detects switch input when the power is off.・
It can also be configured to turn off.

[Brief explanation of drawings]

FIG. 1 is a front cross-sectional view showing the schematic structure of a copying apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing the positional relationship between the document table and the main body, and FIG. FIG. 4 is a circuit diagram relating to the microprocessor, various switches and power supply circuits, and FIG. 5 is a flowchart showing the processing procedure of the microprocessor.

Claims (1)

[Claims] 1. A document placing table, a scanning means for reciprocating the document placing table, a position detecting means for detecting the position of the document placing table, a means for detecting an instruction to turn off the power, and a means for detecting the instruction to turn off the power. At this time, the position of the document placing table is detected by the position detecting means, and if the document placing table is not at the initial position, the scanning means is operated to return the document placing table to the initial position, and then the power is turned off. 1. A copying apparatus comprising means for turning off.