JPH067935B2 - Document shredder - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document shredding machine having a function of automatically starting shredding when an object to be shredded and automatically stopping when shredding ends. It is about.

2. Description of the Related Art A conventional document shredder of this type will be described with reference to FIGS.

In FIG. 4 and FIG. 5, a motor 4 and a motor 4 are provided in the main body 3 formed by the upper body 1 and the lower body 2.
Cutter 6 which rotates by receiving power from gear 5
The light emitting element 8 and the light receiving element 9 are provided opposite to each other on the inner wall of the insertion port 7 that is built in and is opened on the upper surface of the main body 3. As shown in FIG. 6, the automatic forward rotation switch 10 is turned on.
Then, the direct current rectified and stepped down by the resistor 12 and the diode 13 is smoothed by the capacitor 14, the direct current power stabilized by the transistor 15 and the Zener diode 16 is supplied to the light emitting element 8, and the signal received by the light receiving element 9 is supplied to the transistor 17 When the next stage transistor 18 is turned on, the relay coil 19-
1 is energized, the relay contact 19-2 is turned on, and the motor 4
Turns forward. Here, using the time constants of the capacitor 20 and the resistor 21, the relay contact 19-2 is turned on for some time even when the transistor 17 is turned on, that is, after the light receiving element 17 no longer detects the shredded object. It is held and stopped after the object to be shredded is completely shredded. In addition, the switch 11 releases the automatic forward rotation switch 10,
After that, the motor 4 is rotated in the reverse direction.

Problems to be Solved by the Invention In such a conventional document shredding machine, when shredding is stopped during automatic shredding and immediate reversal is performed, for example, an important document is shredded by mistake. , When the sudden return is attempted, by turning on the reverse rotation switch 11, the automatic forward rotation switch 10 is turned off, but at this time, the relay contact 19-2 is delayed because the DC power source is gradually lowered by the capacitor 14. It does not turn off immediately because the circuit operates. When the reverse switch 11 is turned on in this state, a voltage is applied to the circuit portion via the motor 4 and the relay contact 19-2. Since the voltage applied at this time is a voltage higher than the power supply voltage in many cases because the motor 4 acts as a transformer, there is a problem that the circuit part is broken down and the life is shortened.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a highly useful document shredder which guarantees stable operation of a circuit portion and prevents a failure life from decreasing.

Means for Solving the Problems In order to solve the above problems, the present invention is to drive a motor to shred the shredded object, and shredded object detection means for detecting the input of the shredded object. And an automatic forward switch for controlling the motor to normally rotate the shredding blade to the shredding side in accordance with the output from the detection means, and to control the motor to reverse the shredding blade to the closing side. A reverse switch and a delay circuit for turning off the automatic forward switch with a delay of a certain time after the completion of throwing in the shredded object is detected by the shredded object detecting means, and the shredding blade is positive. When the reverse rotation switch is operated during rotation, the reverse rotation switch is provided with a contact for releasing the power supply to the delay circuit before starting the control of the motor.

Effect of the Invention With the above-described configuration, when the shredding is stopped and the reverse rotation switch is turned on immediately while shredding by the automatic forward rotation, the delay circuit is released before the reverse rotation terminal of the motor is connected to the power source, and The forward rotation terminal, the power supply and the control circuit are each opened, and when the reverse rotation switch is connected, it is possible to prevent the power supply voltage from being applied to the control circuit through the forward rotation terminal of the motor.

Example Hereinafter, an example will be described with reference to the drawings.

In FIGS. 1, 2 and 3, a main body 103 formed by an upper body 101 and a lower body 102 is provided with a motor 104 and a cutter 106 for decelerating and transmitting the rotational force of the motor 104 via a gear 105. It is built in.
On the inner wall of the charging port 107 opened on the upper surface of the main body 103,
The light emitting element 108 and the light receiving element 109 are provided opposite to each other. When the automatic forward rotation switch 110 is turned on, the resistance 112
The DC power rectified and stepped down by the diode 113 is smoothed by the capacitor 114, the DC power stabilized by the transistor 115 and the Zener diode 116 is supplied to the light emitting element 108, and the signal received by the light receiving element 109 is turned on by the transistor 17-. It is converted to an OFF signal and input to the transistor 118 in the next stage. Transistor 11
A relay coil 119-1 is connected to the collector of No. 8, and this relay contact 119-2 connects the power source and the normal rotation terminal of the motor 104 via the automatic forward conversion switch 110. The contact point 122 is the charge of the capacitor 120 of the delay circuit including the capacitor 120 and the resistor 121 for providing the delay time until the relay contact 119-2 is released after the light receiving element 109 no longer detects the shredded object. This is for discharging and releasing the delay circuit, and is linked with the reverse switch 111, and the reverse switch 111 is turned on.
It is turned on before N. The resistor 123 and the capacitor 124 convert the current of the light receiving element 109 into a voltage and input it to the transistor 117 through the diode 125.

As described above, the operation according to the above configuration is performed by the light receiving element
When the object to be shredded is detected, the potential of the resistor 123 decreases, the transistor 117 turns off, and the capacitor 120 turns the resistor 1
While being charged via 26, the transistor 118 is turned on, the relay coil 119-1 is energized, the relay contact 119-2 is turned on, and the motor 104 is rotating normally.
At this time, when the reverse rotation switch 111 turns off the automatic forward rotation switch 110, the capacitor 114 supports the DC power supply of the control circuit and the capacitor 12
The relay contact 119-2 is in the ON state while the delay circuit due to the discharge of 0 is operating, but the reverse switch 11
1 is turned on, the contact 112 is turned on to instantaneously discharge the electric charge of the capacitor 120 of the delay circuit, and the power source transformed through the motor 104 through the reverse switch 111 via the relay contact 119-2 is a control circuit. Can be prevented from being applied to. Capacitor 120 here
A discharge resistor may be appropriately inserted in the discharge path.

EFFECTS OF THE INVENTION As described above, according to the present invention, after the automatic forward rotation switch is released, before the contact for reverse rotation is closed, there is a contact for releasing the circuit that delays the stop of automatic forward rotation. By configuring the reverse switch, the shredding is stopped during automatic shredding, and even if the reverse switch is operated immediately, abnormal voltage is prevented from being applied to the control circuit, ensuring stable operation of the circuit part. And then a failure. It is possible to provide a highly useful document shredder which prevents the life of the document from being shortened.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a document shredder according to an embodiment of the present invention,
2 is a perspective view of the same, FIG. 3 is a sectional view of the same, and FIG.
FIG. 5 is an external perspective view of a conventional document shredder, FIG. 5 is a sectional view of the same, and FIG. 6 is a circuit diagram thereof. 104 ... Motor, 110 ... Automatic forward switch, 11
1 …… Reverse rotation switch.

Claims (1)

[Claims] 1. A shredding blade driven by a motor to shred an object to be shredded, shredded object detection means for detecting an input of the shredded material, and the shredded material according to an output from the detection means. An automatic forward switch for controlling the motor so as to rotate the blade forward to the shredding side, a reverse switch for controlling the motor so as to reverse the shredding blade to the closing side, and a shredded object detected by the shredded object detecting means. It is composed of a delay circuit that turns off the automatic forward rotation switch with a delay of a certain time after the completion of throwing the scraps off, and controls the motor when the reverse rotation switch is operated while the shredding blade is rotating forward. A document shredding machine having a reversing switch provided with a contact for releasing power supply to the delay circuit before starting.