JPH059140B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a shredder for shredding discarded documents, etc., and particularly relates to an improvement of an operation control switch.

(b) Prior Art A shredder is a device that shreds documents to be disposed of in order to maintain the confidentiality of the documents. A typical shredder shreds paper sheets into lines several millimeters wide by passing the paper sheets between two rotating blades (see FIG. 4A) that mesh with each other.
The rotary blade is driven by a motor. In order to save the user the trouble of inserting paper sheets and starting the motor separately, a paper entry sensor is installed at the paper entry slot, and when this paper entry sensor detects the insertion of paper sheets, Shredders that start the motor (auto start) have been put into practical use.

(c) Problems to be Solved by the Invention However, in such a device, the operation always starts when the paper entry sensor detects an object. There was a problem in that the cutter device was driven even when the cutter device was detected. Since it is extremely dangerous to have no means to stop the operation in such a case, it is necessary to provide the device with an emergency stop switch. Furthermore, it is desirable to also provide a so-called reversing switch, since it may be necessary to reverse drive the cutter device in order to pull out the entangled object (necktie, etc.).

However, installing such switches on the panel of the device not only clutters the panel, but also makes it impossible to immediately determine which switch to turn on in case of an emergency, resulting in a delay in response. There is a point.

This invention focuses on the fact that an emergency stop switch and a reversing switch are never operated at the same time, and aims to provide a shredder that solves the above problem by using one specific switch for both functions. .

(d) Means for Solving the Problems The present invention has a cutter device that shreds input paper sheets while conveying them, and automatically drives the cutter device by detecting the input of paper sheets. The shredder is provided with one push button switch, a reversing means for operating the cutter device in the opposite direction when the push button switch is turned on while the cutter device is stopped, and while the cutter device is being driven, An emergency stop means for stopping the drive of the cutter device when the push button switch is turned on.

(e) Effect of the Invention The shredder of the present invention has a reversing means for reversing the cutter device when the push button switch is turned on while the cutter device is stopped, and a reversing means that reverses the cutter device when the push button switch is turned on while the cutter device is being driven. An emergency stop means for stopping the cutter device is provided. This allows one push button switch to be used as a reverse switch/emergency stop switch.
All you have to do is turn on this push button switch and you will be able to respond to emergencies.

(f) Embodiment Figure 2 is a perspective view of the upper part of a shredder that is an embodiment of the present invention, Figure 3 is a schematic diagram showing the internal structure of the shredder, and Figures 4A and B are used in the shredder. It is a figure showing the structure of a cutter roller and a spiral cutter. An input port 2 for inputting paper sheets to be discarded is diagonally provided on the upper surface of the shredder main body 1, and a paper entry sensor 5 (Sp) is provided on the upper side wall inside the input port 2. This paper entry sensor 5 is a reflective optical sensor, and has a light projecting part and a light receiving part both facing the opposite side wall 2a. When paper sheets are not inserted, the light receiving section receives reflected light from the opposite side wall 2a, but when paper sheets are inserted, it receives reflected light from the paper sheets, and the amount of light received fluctuates. The paper input is detected by doing this. Note that the side wall 2a is painted black to reduce reflectance. In addition, an operation panel is provided on the right side of the input port 2 on the top surface of the device, and a push button switch 3 is located on this operation panel.
(SW) and a plurality of LEDs 4 are provided.
The push button switch 3 functions as an emergency stop switch/reverse switch, as will be described later. This push button switch 3 corresponds to a specific switch of the present invention. Further, the LED 4 includes a power indicator, an operating indicator, a door indicator, a waste container full indicator, and the like. There are two cutter rollers 8 inside the input port 2.
a and 8b are provided so as to mesh with each other, and the rear end portion of the input port 2 is exactly opposite to the meshing portion. The cutter rollers 8a and 8b are shown in Fig. 4A.
As shown in the figure, disc-shaped cutter blades 82 are attached to a rotating shaft 81 at equal intervals. Further, a lateral cutter device 9 is provided directly below the meshing portion of these cutter rollers 8a, 8b. This horizontal cutter device 9 has a spiral cutter 9a having a spiral blade and a flat cutter (not shown) inside a cover 9b having a horizontal cylindrical shape with slit-like openings on the upper and lower sides. The spiral cutter 9a has a shaft 91 and a spiral cutter blade 92. The cutter rollers 8a, 8b and the spiral cutter 9a are connected to a motor 7 (M) via a gear system 10 shown in broken lines, and are driven by the rotation of the motor 7. The motor 7 has an output of about several hundred watts.

Here, when paper sheets are inputted from the input port 2, the paper input sensor 5 detects this and the motor 7 is automatically started. This causes the cutter rollers 8a, 8b and the spiral cutter 9a to rotate. The input paper sheets are shredded into linear pieces with a width of about 4 mm by cutter rollers 8a and 8b. The linearly shredded paper sheets are guided into the horizontal cutter 9 and cut into even shorter lengths. The cutting length is determined by the number of rotations of the spiral cutter 9a, and is about 3 mm to 9 mm. The paper sheets (shredded waste) that have been finely cut in this way fall into a waste container 11 provided at the bottom of the apparatus. A waste sensor 6 is disposed diagonally above the waste container 11.
(Sd) is provided to detect the accumulation of shredded waste. This waste sensor 6 is also a reflective optical sensor similar to the paper entry sensor 5. However, the light emission intensity of the light emitting section and the light receiving sensitivity of the light receiving section are each adjusted according to the function.

FIG. 5 is a block diagram of the control section of the shredder. The operation of this shredder is controlled by a controller consisting of a microcomputer.
The paper input sensor 5, waste sensor 6, and push button switch 3 are connected to the controller, and also includes a motor driver 21 that drives the motor 7 and an LED driver 2 that lights the LED 4.
2 are connected. The controller 20 controls driving (forward rotation/reverse rotation)/stopping of the motor based on the detected status of the sensor or switch, and lights up an LED indicating the operating status.

FIG. 6 is a block diagram showing the circuit configuration of the reflective optical sensor. This reflective optical sensor is used as a paper entry sensor 5 and a waste sensor 6. An infrared LED 37 that irradiates light onto an object and a photodiode 30 that receives this reflected light are installed in parallel facing the same direction. Infrared LED 37 is LED lighting circuit 36
It is lit by. An oscillator 35 is connected to the LED lighting circuit 36, and is modulated by the LED drive current and the high frequency oscillated by the oscillator 35.
Further, the photodiode 30 is connected to an amplifier 31. The amount detected by the photodiode 30 is amplified by an amplifier 31, and compared by a comparator 32 to determine whether the detected amount exceeds a threshold value. This comparison result is input to the synchronization detection circuit 33. The synchronization detection circuit 33 is a circuit that extracts an output synchronized with the oscillation frequency of the oscillator 35, thereby making it possible to prevent erroneous detection due to ambient light. The output of the synchronization detection circuit 33 is input to a demodulation circuit 34, where it is demodulated and output as a continuous on/off signal. This output is input to the controller 20 in this shredder. In the above circuit, the circuits excluding the infrared LED 37 (including the photodiode 30) can also be configured with one IC.

When using this reflective optical sensor as the dust sensor 6, the detection sensitivity is set high because there is a distance to the detection target and there is little specularly reflected light. Here, the amount detected by the photodiode 30 is proportional to the height of the accumulated shredded debris, but the determination as to whether the debris container 11 is full may be made by the comparator 32 or by the controller 20. Good too.

Further, when this reflective optical sensor is used as the paper entry sensor 5, the detection sensitivity may be kept low because the opposite side wall 2a is close and paper sheets also pass nearby.

FIG. 7 is a diagram showing a storage area provided in the memory of the controller 20.

Fd: Debris detection flag is a flag that is set when the debris sensor 6 (Sd) detects shredded debris.

Fp: Paper entry detection flag is a flag that is set when the paper entry sensor 5 (Sp) detects paper sheets.

Fe: The emergency stop flag is a 3-state flag that is set based on whether the push button switch 3 (SW) is turned on or off while the motor 7 (M) is operating. Normally, it is set to "0", and when the push button switch is turned on while the motor is operating, it is set to "1". If the push button switch is then turned off, "2" is set until no paper sheets are detected (until the jam is cleared). push button switch 3
(SW), the status of this flag is “0”,
When set to “1”, it functions as an emergency stop switch,
When the status is "2", it functions as a reverse switch.

Cd: Debris detection time counter is a counter that measures the time during which the debris sensor 6 continuously detects shredded debris. When this counter counts 20 ms, it is determined that the waste container 11 is full of shredded waste. That is, since the waste sensor 6 detects falling pieces as well as the pieces accumulated in the waste container 11, a 20ms wait is required to eliminate the short detection pulse caused by the falling pieces. I set a time.

Cp: Paper entry detection time counter is a counter that measures the time during which the paper entry sensor 5 continuously detects paper sheets. When this counter counts 20 minutes, the device is forcibly stopped due to a paper jam or false detection. In other words, the motor 7 is prevented from being overheated and damaged due to malfunctions due to paper jams or erroneous detection, which is a drawback of the auto-start method in which the motor 7 is automatically started when the paper sensor 5 detects paper sheets. There is.

Cw: Waiting time counter is a timer counter for continuing to drive the motor 7 for a certain period of time (approximately 3 seconds) after the paper input sensor 5 no longer detects paper sheets. After the paper input sensor 5 stops detecting paper sheets, that is, after the trailing edge of the paper sheet passes the paper input sensor 5, it takes 3 seconds to complete shredding of the input paper sheets. This is because it takes a considerable amount of time, and also because the motor 7 is to be operated smoothly and continuously without repeating driving/stopping when paper sheets are continuously inputted.

FIG. 1 is a flowchart showing the operation of the control section. When the device is powered on, it first performs initial operations such as clearing each register (n1). Next, turn on/off the push button switch (SW).
Judging off (n2). While motor (M) is stopped (n2 is executed only when M is stopped.)
When SW is turned on, M is reversed (n3). Here, the drive control of the motor M is performed by dynamic control. That is, the controller 20 outputs a reverse rotation signal every time n3 is executed. The motor driver 21 continues to rotate the motor 7 in reverse while this reverse rotation signal is input at regular intervals. The same applies to forward rotation; each time the controller 20 executes operation n27, which will be described later, a forward rotation signal is output, and while this forward rotation signal is input at regular intervals, the motor driver 21 rotates the motor 7 in the forward rotation. let

Next, n10 determines whether the paper entry sensor (Sp) is on or off. If Sp is on, first set the wait time counter (Cw) to a count value equivalent to 3 seconds (n11), then set the paper entry detection flag (Fp).
Determine whether to set/reset (n12). If Fp has been reset, set Fp (n13)
Proceed to n22. Also, if Fp is set, the paper entry detection time counter (Cp) is counted up (n14), and if Cp reaches 20 minutes (n15),
Stop the operation of the device to prevent the motor from overheating (n41). n15 if Cp does not count 20 minutes
→Proceed to n22.

On the other hand, if n10 detects that Sp is off, it means that no paper sheets are detected in the input slot 2, so reset Fp and clear Cp (n16), then determine whether SW is on or off. (n17). SW
is off, the emergency stop flag (Fe)
Set (reset) 0 to (n18) and proceed to n19. On the other hand, when the SW is on, changing the SW function (emergency stop function/reverse function) would be dangerous to the user, so proceed to n19 without changing the Fe status (skipping n18). In n19, determine Cw. If Cw=0, proceed from n19 to n21.
In n21, judge Fe and if Fe=1, return to n4,
If Fe≠1 (Fe=0,2), it returns to n2. In other words, when Fe=1, the SW functions as an emergency stop switch, so the motor should not be reversed.
Skip n2 and n3. Also, if Cw > 0,
Count down Cw and proceed to (n20) n22.

In n22 to n24, ON/OFF of SW and status of Fe are determined. When Fe=2, it is assumed that an emergency stop is in progress and the process returns to n22→n2. Fe≠2 and SW=
When it is on, it is assumed that the motor stop switch is on, and Fe is set to 1 (n23→n25), and the process returns to n4. Also, when SW = OFF and Fe = 1, 2 is applied to Fe.
Set (n24→n26) and return to n2. As a result, no paper sheets are detected thereafter (the paper jam is cleared), and the SW functions as a motor reverse switch until the operation of n18 (resetting Fe) is executed. When SW=off and Fe=0, n22 to n24
→Proceed to n27 and output a normal rotation signal of the motor M to the motor driver 21. After this, a shredded waste detection operation is executed.

In the shredded waste detection operation, first, it is determined whether the waste sensor (Sd) is on or off (n30). If Sd is not on, it is assumed that the waste container 11 is not full, the waste detection flag (Fd) is reset, the waste detection time counter (Cd) is cleared, and the process returns to n10 (n31).
If Sd is on, determine whether to set/reset Fd (n32). If Fd is not set, set Fd (n33) and return to n10. If Fd is set, Cd is counted up (n34), and when Cd reaches 20 ms (n35), it is assumed that the waste container 11 is full and the operation of the device is stopped (n42). If Cd does not count 20ms, it returns from n35 to n10. Since the detection pulse width of falling shredded debris is less than 20ms,
This operation makes it possible to distinguish between the accumulated shreds and the falling shreds. When the operation stops at n42, the waste container full indicator on the operation panel lights up at the same time to prompt the user to dispose of the waste. After turning off the power, empty the waste container 11 and turn on the power again to return to the operation from n1.

n2 and n3 correspond to the reversing means of the present invention, and n23 corresponds to the emergency stop means of the present invention.

(g) Effects of the Invention As described above, according to the shredder of the present invention, the function of one push button switch is changed to a reversing switch/emergency stop switch while the cutter device is stopped/operating. The number of switches that are turned on at one time can be reduced to one, and the operation panel can be simplified. In addition, in any case, it is possible to respond to emergencies simply by turning on this switch, so it is possible to ensure the safety of users.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the operation of the control section of a shredder according to an embodiment of the present invention, FIG. 2 is a perspective view of the upper part of the shredder, FIG. 3 is a schematic diagram showing the internal structure of the shredder, and FIG. 4 A and B are diagrams showing the structures of a cutter roller and a spiral cutter used in the same shredder. Fig. 5 is a block diagram of the control unit of the shredder, Fig. 6 is a block diagram of a reflective optical sensor used as the paper input sensor of the shredder, and Fig. 7 is a partial configuration diagram of the memory of the control unit. be. 3 (SW)...Push button switch, 7...Motor.

Claims (1)

[Scope of Claims] 1. A shredder that has a cutter device that shreds input paper sheets while conveying them, and that detects the input of paper sheets and automatically drives the cutter device; a button switch; reversing means for operating the cutter device in the opposite direction when the push button switch is turned on while the cutter device is stopped; A shredder comprising: an emergency stop means for stopping the drive of the cutter device when the cutter device is turned off.