JPH02303550A - Shredder - Google Patents

Abstract

PURPOSE:To obviate the stop, etc., of the device by an erroneous detection and to improve reliability by making judgment that a container is full of paper leaves when the detection of the paper leaves by reflection type optical sensors continues for a specified period of time or longer by a full detecting means. CONSTITUTION:The paper leaves charged to the device are shredded and the shredded paper leaves are deposited and stored in the container 11. The reflection type optical sensors 5, 6 are installed toward this container 1. The full detecting means judges that the container 11 is full of the paper leaves when the detection of the paper leaves by the reflection type optical sensors 5, 6 continues for the specified period of time or longer. As a result, the paper leaves under falling (shredding dust) and the deposited paper leaves (shredding dust) are surely identified and the stop, etc., of the device by the erroneous detection are obviated and the reliability is improved.

Description

[Detailed Description of the Invention] +al Industrial Field of Application This invention provides a method for shredding discarded documents,
In particular, it relates to improvements in the fullness detection method for shredded waste.

BACKGROUND ART A conventional technology shredder is a device that shreds documents to be discarded 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. 4(A)) that mesh with each other. The shredded paper sheets (shredded waste) are accumulated and stored in a waste container housed at the bottom of the device. When the waste container is full of shredded waste, no further operation is possible, so the device stops operating or lights up a warning lamp to prompt the user to dispose of the shredded waste.

For this reason, a waste sensor is provided inside the shredder to detect the accumulation of shredded waste in the waste container. Recently, reflective optical sensors have been used as debris sensors.

(C) Problems to be Solved by the Invention The reflective optical sensor is installed from above the waste container toward the inside of the container so as to be able to detect the upper end of the accumulated shredded waste. That is, the waste sensor detects the distance between the sensor and the shredded waste. When this distance becomes less than a certain value,
The control unit assumes that the container is full of shredded waste and prompts for disposal.

However, the reflective optical sensor installed in this way detects not only the accumulated shreds but also the shreds that have been shredded by the force lid and are falling into the container, so false detections occur constantly. This has the disadvantage that the waste container is judged to be full even though there is sufficient capacity, resulting in unnecessary effort for the user.

An object of the present invention is to provide a shredder that solves the above problems by taking detection duration into consideration.

(d+ Means for Solving the Problems) This invention provides a shredder that shreds input paper sheets and accumulates and stores the shredded paper sheets in a container, in which a reflective optical sensor is directed toward the container. The present invention is characterized in that it is provided with a fullness detection means that determines that the container is full of paper sheets when the detection of paper sheets by the reflective optical sensor continues for a certain period of time or more.

(Ill) Effect of the Invention The shredder of the present invention has a waste sensor made of a reflective optical sensor directed toward a container in which shredded waste is deposited and stored.

This debris sensor detects not only the accumulated debris but also the falling debris, but it is determined that the accumulated debris has been detected only when the detection continues for a certain period of time (approximately 20m5). I did it like that. That is, since the fine pieces of falling shredded waste are fine, each period of time is about several ferrets, and if the detection of several tens of ferrets continues, it can be assumed that accumulated shredded debris has been detected. This makes it possible to distinguish between falling shredded debris and accumulated shredded debris, making it possible to accurately detect fullness.

(f) Embodiment FIG. 2 is a perspective view of the upper part of a shredder that is an embodiment of the present invention, FIG. 3 is a schematic diagram showing the internal structure of the shredder, and FIGS. 4 (A) and (B) are the same. It is a figure showing the structure of a cutter roller and a spiral cutter used for a shredder. An input port 2 for inputting paper sheets to be shredded 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 is a reflection type optical sensor, and both a light projecting part and a light receiving part are installed 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. Incoming paper 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 (
SW) and a plurality of LEDs 4 are provided. The pushbutton switch 3 functions as a stop/reverse switch as described below, and the LED 4 includes a power indicator, an in-operation indicator, a door indicator, a waste container full indicator, and the like. Two cutter rollers 8a and 13b are provided inside the input port 2 so as to mesh with each other, and the rear end portion of the input port 2 is arranged to directly oppose the meshing portion. Cutter roller 8
As shown in FIG. 4(A), a and 8b have disc-shaped cutter blades 82 attached to a rotating shaft 81a at equal intervals. Further, a lateral cutter device 9 is provided directly below the meshing portion of these cutter rollers 8a and 8b. This lateral force lid device 9 has a horizontal cylindrical shape with slit-like openings on the upper and lower sides, and a spiral cutter 9a is connected to a motor 7 (M) via a gear system 10 shown by a broken line. Driven by rotation. The motor 7 has an output of about several hundred watts.

Here, paper sheets inputted from the input port 2 are shredded into linear pieces with a width of about 4fi by counterrollers 3a and 8b. The linearly shredded paper sheets are guided inside the horizontal canter 9,
It is cut even shorter. Cutting length is spiral cutter 9
It is determined by the rotation speed of a, and is about 3 fl to 9 fl. Paper leaves cut into small pieces like this (shredded waste)
falls into the waste container 1) provided at the bottom of the device. A waste sensor 6 (Sd) is provided diagonally above the waste container 1) 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 Schlefda. The operation of this shredder is controlled by a controller consisting of a microcomputer.

The controller includes the paper input sensor 5. A waste sensor 6 and a push button switch 3 are connected, and a motor driver 21 that drives the motor 7 and an LED 4 are connected.
An LED driver 22 for lighting is connected. The controller 20 controls driving (forward rotation/reverse rotation)/stopping of the motor based on the detected state of the sensors and switches, and lights up an LED indicating the operating state.

FIG. 6 is a block diagram showing the circuit configuration of the reflective optical sensor. These reflective optical sensors include a paper entry sensor 5 and a waste sensor 6.
used for. 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 LE
It is lit by the D lighting circuit 36. LED lighting circuit 3
An oscillator 35 is connected to 6, 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 the oscillator 3
This is a circuit that takes out an output synchronized with the oscillation frequency of 5.
This makes it possible to prevent erroneous detection due to ambient light. The output of the synchronization detection circuit 33 is input to the demodulation circuit 34,
It is demodulated and output as a continuous on/off signal.

This output is output from the controller 20 in this shredder.
is input. In the above circuit, the circuit other than the infrared LED 37 (including the photodiode 30) can also be configured with one IC.

When this reflective optical sensor is used as the debris 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 or not the debris container 1) is full may be made by the comparator 32 or the controller 20. It's okay.

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: The layer detection flag is a flag that is set when the waste sensor 6 (Sd) detects shredded waste.Fpz The paper entry detection flag is set when the paper entry sensor 5 (Sp) detects paper sheets. This is the flag to be used.

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, 1" is set. If the push button switch is turned off after that, the paper sheet is not detected (jam is detected). The push button switch 3 (SW) functions as a motor stop switch when the status of this flag is ``O'' or ``'l'', and the status is ``2'' until the status is ``2''. Functions as a motor reversal switch when

Cd: Layer detection time counter is a counter that measures the time during which the waste sensor 6 continuously detects shredded waste. When this counter counts 2 (1+a), it is determined that the waste container 1 is full of shredded waste. That is, since the waste sensor 6 detects not only the shredded waste accumulated in the waste container 1) but also the fallen shredded waste, it is necessary to remove the short-term detection pulse caused by the falling shredded waste. The Cp two-person paper detection time counter, which has a waiting time of , is a counter that measures the time during which the paper entry sensor 5 continuously detects paper sheets. When this counter counts 20 minutes, it is assumed that there is a paper jam or an erroneous detection, and the apparatus is forcibly stopped. In other words, the motor 7 is prevented from being overheated and damaged due to malfunctions due to paper jams or erroneous detections, which are drawbacks of the auto-start method in which the motor 7 is automatically started when the paper sensor 5 detects paper sheets.

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 entry sensor 5 no longer detects paper sheets. After the paper input sensor 5 no longer detects paper sheets, that is, after the trailing edge of the paper sheet passes the paper input sensor 5, it takes about 3 seconds to complete shredding of the input paper sheets. This is because it takes 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, initial operations such as clearing each register are performed (nl). Next, determine whether the push button switch (SW) is on or off (n2)
. When the SW is turned on while the motor (M) is stopped (n2 is executed only while M is stopped), M is reversed (n3). Here, 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, and the controller 20 outputs a forward rotation signal every time it executes the operation n27 described later, 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, it is determined whether the paper entry sensor (Sp) is on or off using nlo. If Sp is on, first the waiting time counter (
After setting the count value corresponding to 3 seconds in (CW),
nil), determines whether to set/reset the paper entry detection flag (Fp) (n12), and if Fp has been reset, cent Fp (n13) and proceed to n22;
If p is set, the paper entry detection time counter (C
p) is counted up n14), and as a result Cp is 2
When the time reaches 0 minutes (n15), the operation of the device is stopped to prevent the motor from overheating (n41). If Cp has not counted 20 minutes, proceed to n15→n22.

On the other hand, if n10 detects that Sp is off,
Since no paper sheets are detected in the input slot 2, Fp is reset and cp is cleared (n16), and then ON/OFF of the SW is determined (n17). If the SW is off, the emergency stop flag (Fe) is set (reset) to O (n18) and the process proceeds to n19. On the other hand, when the SW is on, changing the SW function (motor stop function/motor reversing function) is dangerous for the user, so the Fe status is not changed (skipping n18) and the process proceeds to n19. At n19, Cw is determined. n1 in case of CW-〇
Proceed to 9→n21. In n21, Fe is determined, and if Fe=1, the process returns to n4, and if Fe≠1 (Fe=0.2), the process returns to n2. That is, when Fe=1, SW functions as a motor stop switch, so n2. Skip n3. Also CW〉
If it is 0, count down Cw (n20)n2
Proceed to step 2.

In steps n22 to n24, the on/off status of the SW and the 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. When Fe≠2 and SW=on, it is assumed that the motor stop switch is on, and Fe
Add 1 cent to (n23-+n25) and return to n4.

Further, when SW=off and Fe=1, 2 is added to Fe and the process returns to n2 (n24→n26). As a result, paper sheets are no longer detected (the paper jam is cleared), and the switch is turned off until the operation of n18 (Fe reset) is executed.
functions as a motor reverse switch. When SW=off and Fe=o, proceed from n22 to n24 → n27 and motor M
A normal rotation signal is output to the motor driver 21. After this, a shredded waste detection operation is executed.

In the shredded debris detection operation, first, it is determined whether the debris sensor (Sd) is on or off (n30). If Sd is not on, it is assumed that the waste container 1) is not full and the layer detection flag (Fd) is set.
After resetting and clearing the layer detection time counter (Cd) (n31), the process returns to nlO. If Sd is on, it is determined whether Fd is napht/reset (n32).

If Fd is not set, set Fd (n
33) Return to nlO. Also, if Fd is set, Cd is counted up (n34), and as a result, Cd
When the distance reaches 20 m (n35), it is assumed that the waste container 1) is full and the operation of the device is stopped (n42). Cd is 20m
If not counted, return to n35→nlO.

Since the detection pulse width of the falling shredded debris is 20as, it is possible to distinguish between the accumulated shredded debris and the falling shredded debris through this operation. When the operation is stopped 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 1) and turn on the power again to return to operation from nl n34. n35 corresponds to the fullness detection means of the present invention.

(g1 Effect of the Invention As described above, according to the shredder of the present invention, by taking the detection duration into consideration, it is possible to detect falling paper sheets (shredded waste) and accumulated paper sheets (shredded waste). ) can now be reliably identified, eliminating equipment stoppages due to false detections and improving reliability.

[Brief explanation of the drawing]

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, and Fig. 3 is a schematic diagram showing the internal structure of the shredder. A) and (B) are diagrams showing the structure of a cutter roller and a spiral cutter used in the same shredder. Figure 5 is a block diagram of the control unit of the shredder, Figure 6 is a diagram of the reflective optical sensor used as the paper entry sensor, etc. of the shredder, and Figure 7 is a part of the memory of the control unit. FIG. 6-waste sensor, 1)-waste container.

Claims (1)

[Claims] (1) In a shredder that shreds input paper sheets and accumulates and stores the shredded paper sheets in a container, a reflective optical sensor is installed facing the container, and the A shredder comprising a fullness detection means that determines that a container is full of paper sheets when the detection of leaves continues for a certain period of time or more.