JPH0515470Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a copying machine such as a copying machine or a printer using electrophotographic technology, and particularly relates to a paper detection system for detecting out of paper or a paper feeding error in a paper feeding section. Regarding equipment.

[Prior art and drawbacks]

FIG. 1 is a diagram showing the configuration around a paper detection device in a paper feed section of a conventional copying machine.

In the figure, a paper detection switch 2 that directly detects the paper is provided to detect the presence or absence of paper in the cassette 1, and the paper in the cassette 1 is moved to the paper feed roller 3, standby switch 4, and registration roller according to the copying operation. 5 to the transfer unit 6, and are consumed one by one. When the last sheet has been carried out, the paper detection switch 2 detects that there is no paper and sends a signal to a control circuit (not shown). The control circuit displays a paper out indication on the operation unit to notify the need for paper replenishment. The operator takes out the empty cassette from the main body and replenishes the cassette with paper. When the operator inserts the paper into the main body, the paper detection switch 2 detects that there is paper and sends a signal to the controller to turn off the paper replenishment display and make copy possible. Make it.

However, this device requires a paper detection switch 2 on the cassette, which requires installation space in copying machines that have become smaller in recent years, and also requires a dedicated switch as the paper detection switch 2, resulting in high costs. have.

Further, FIG. 2 is a configuration diagram of the vicinity of a paper detecting device in another conventional paper feeding section.

In the figure, when a copy switch (not shown) is pressed, the paper feed roller 3 rotates and paper is fed out from the cassette 1. At the same time, a timer is started so as to time out after enough time has elapsed for the paper to reach the standby switch 4.

When paper is carried in and reaches the standby switch 4 before the timer times up, it is determined that paper feeding is normal. On the other hand, there is 1 sheet of paper in cassette 1.
If there are no sheets left, the standby switch 4 is not turned on within a predetermined time even if the paper feed roller 3 rotates, so the controller determines that there is no paper in the cassette or that a paper jam has occurred, and operates the display accordingly. This is a device that displays the information on the screen.

When the operator takes out the empty cassette from the main body, the cassette detector 7, which had previously detected the presence of a cassette using the magnet 8,
Since the magnet 8 attached to the cassette 1 is removed from the cassette, the cassette detector 7 is turned off. At this time, the out-of-paper state is reset at the same time, or the out-of-paper state is reset when the cassette 1 is replenished with paper and the operator attaches it to the main body. This device also turns off the paper out display and notifies the operator.

However, this device also requires the above-mentioned cassette detector 7, and has the same drawbacks as the conventional example.Furthermore, even when the cassette 1 is attached to the main body, there is some wobbling due to the provision of some margin. This backlash also has the disadvantage of causing malfunction in the cassette detector 7.

[Purpose of invention]

In view of the above-mentioned drawbacks of the conventional technology, the present invention is a low-cost copying machine that uses a conventional standby switch to detect and reset paper out or paper feeding errors in the paper feed section without requiring much space. The purpose is to provide equipment.

[Key points of the idea]

In order to achieve the above object, the present invention does not include a detection means for detecting the presence or absence of paper in the cassette. A copying apparatus that stops a copying operation and displays an indication that there is no paper, comprising: a maintenance means for stopping the copying operation and maintaining the display thereof; and a clocking means for counting the time elapsed from the stoppage of the copying operation; The present invention is characterized in that when the elapsed time reaches a predetermined time, the maintaining means stops the copying operation and cancels the display.

[Example of idea]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 3 is a configuration diagram of a paper detecting device in a paper feeding section of a copying apparatus according to the present invention.

In the figure, a paper feed roller 10 is provided on a cassette 9 for carrying paper into the machine.
A standby switch 12 is provided above the conveyance path between the paper sheet 0 and the registration roller 11 to detect the passage of paper. Further, the paper carried into the machine passes through a conveyance path and is carried between the photosensitive drum 13 and the transfer device 14 by the registration rollers 11.

FIG. 4 also shows when the above-mentioned standby switch 12 is turned on and
FIG. 7 is a circuit diagram for detecting out of paper or paper feeding error based on the off state.

In FIG. 4, the standby switch 12 is a reflective type photo switch with an LED (light emitting diode) 12a and a photo transistor 1.
2b, the LED 12a and the phototransistor 12b are connected in parallel via resistors 15 and 16, respectively, and one end of the parallel circuit is connected to the power supply and the other end is grounded.

On the other hand, a paper feed clutch 18 for driving the paper feed roller 10 is connected to the output O ₁ of the microcomputer 17 via a logic NOT circuit 19 . Further, an oscillator 20 such as a multivibrator and a timer circuit 21 are connected to the output O ₂ of the microcomputer 17. The other end of the oscillator 20 is connected to a paper supply/feed error indicator lamp 22. The other end of the timer circuit 21 is connected to the microcomputer 17.
is connected to the input terminal i ₁ of the phototransistor 12.
The connection point between b and resistor 16 is microcomputer 1.
It is connected to input terminal _i2 of 7. On the other hand, a diode 2 is installed in the paper feed clutch 18 to prevent instantaneous reverse current.
3 are connected in parallel.

The operation of detecting no paper or misfeeding paper and canceling the detection in the paper detecting device having the above configuration will be described below with reference to the flowchart of FIG.

First, the microcomputer 17 is put into start mode. Next, determine whether the copy switch is turned on (ST1). If the answer is YES, that is, the copy switch is turned on, a command is issued to turn on the paper feed clutch 18 (ST2). At the same time as this command (ST2), a timer circuit 21 is set so that the timer circuit 22 sets the timer to a time slightly longer than the time the paper is fed from the cassette 9 and reaches the standby switch 12.
(ST3).

Next, it is determined whether the standby switch is turned on depending on the fed paper (ST4). If YES, the copy operation (ST10) begins.

If the judgment in (ST4) is NO, it is checked whether the timer circuit 21 started in (ST3) has timed up (ST5). If it is before time-up, return to (ST4). If the time has elapsed, it is determined that there is no paper or there is a paper feed error, so the paper feed clutch 18 is turned off (ST6). At the same time, the microcomputer 17 outputs to the output O ₂ (ST7) and drives the oscillator 20 and timer circuit 21. The output of the oscillator 20 causes the paper replenishment/feed error indicator lamp 22 to blink.

Next, the timer circuit 21 times up and inputs i ₁
Check if there is an input (ST8). If no, return to (ST7). If YES, that is, there is an input to _i1 , the output _O2 is turned off (ST9), and the oscillator 20 and timer circuit 21 are turned off. Timer circuit 21
By resetting, the display lamp 22 is also turned off.

Therefore, according to the present invention, the indicator lamp that indicates out of paper or paper feeding error is blinked, and the indicator lamp is turned off after a certain time-up period set in the timer circuit 21 has elapsed by resetting the timer circuit 21. I can do it.

The embodiment of the present invention is not limited to the above, and the oscillator 20 and timer circuit 21 used in this embodiment may be built in the microcomputer 17.

[Effect of idea]

As described in detail above, according to the present invention, a standby switch is used instead of a switch that directly detects the presence or absence of paper in the cassette, thereby eliminating the need for a detector for detecting the absence of paper and for resetting. For this reason, the cost of the device is low, and the device is compact without taking up much space. Furthermore, it is possible to display the fact that there is no paper for a certain period of time and then automatically reset the no-paper state.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the area around the paper detection device in the paper feed section of a conventional copying device, FIG. 2 is a block diagram of the area around the paper detection device in another conventional paper feed section, and FIG. 3 is a block diagram of the area around the paper detection device in the paper feed section of a conventional copying device. FIG. 4 is a circuit diagram of the paper detecting device of the copying machine according to the present invention, and FIG. 5 is a flowchart for explaining the operation of the paper detecting device of the copying machine according to the present invention. . 9...Cassette, 10...Paper feed roller, 11...
Registration roller, 12...Standby switch, 12a
...LED, 12b...Phototransistor, 1
3...Photosensitive drum, 14...Transfer device, 15,1
6...Resistor, 17...Microcomputer, 1
8...Paper feed clutch, 19...Logic negation circuit, 2
0...Oscillator, 21...Timer circuit, 22...
Indicator lamp, 23...diode.

Claims (1)

[Scope of utility model registration request] If there is no detection means for detecting the presence or absence of paper in the cassette, and the paper detection means provided on the paper transport path does not operate within a set time from the start of paper feeding operation,
The copying apparatus that stops the copying operation and indicates that there is no paper, comprising: a maintaining means for stopping the copying operation and maintaining the display; and a clocking means for counting the time elapsed from the stoppage of the copying operation, A copying apparatus characterized in that when the elapsed time reaches a predetermined time, the maintaining means stops the copying operation and cancels the display.