JPH0229378B2 - BUNSHOSAIDANKI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a document shredding machine for shredding documents and the like.

Conventional configurations and their problems Conventionally, there are various configurations in which the cutter is started by inserting the paper to be shredded into the input slot. The type that detects this has the disadvantage that if the cutter is overloaded, it becomes locked, and when the cutter is turned over, the shredded material flows backwards and gets caught in the actuator, causing a malfunction.

Purpose of the Invention The present invention solves these conventional drawbacks by arranging a light-emitting element and a light-receiving element to face each other, and starting a motor when documents to be shredded are placed between them. It is an object of the present invention to prevent malfunctions caused by external light, to keep the motor rotating for a certain period of time even after the document passes through the detection section, and to prevent documents from remaining in the cutting section.

Structure of the Invention The document shredding machine of the present invention drives a light emitting element, which is disposed opposite to a light receiving element across a document input slot, with pulses of a constant period, and detects the pulse of light by the light receiving element. The capacitor that makes up the timer is charged with the output, so even if the light receiving element is affected by external light, the output of the detected pulse does not change, so the capacitor that makes up the timer is reliably charged. . Furthermore, when a document is inserted, the light pulse output from the light receiving element disappears, so the capacitor is not charged and its potential drops.

The potential across the capacitor is detected and the motor is energized when the potential falls below a certain level.

Description of examples Examples thereof will be described below with reference to the drawings.

In the figure, 1 is a waste box, and 2 is a document shredding machine body that is detachably installed in the upper opening of the waste box 1. Inside is a cutter 3 and a motor that drives this cutter 3 via a speed reducer. 4 is provided. A light-emitting element 6 is disposed on one wall of the shredded material inlet 5 provided above the cutter 3, and a light-receiving element 7 is disposed in correspondence with the light-emitting element 6 on the other wall of the inlet 5. ing.

The output of a pulse generation circuit 8 is connected to a light emitting element 6 made of a light emitting diode or the like, and the output of a light receiving element 7 made of a phototransistor or the like is connected to a detection circuit 9 for detecting pulses. The detection circuit 9 detects only the AC output of the light receiving element 7 and charges the capacitor 10. The voltage of the capacitor 10 is determined by a voltage comparator 12 with a reference voltage 11 connected to one end.
is connected to the input terminal of this voltage comparator 1.
The output of No. 2 is connected to a motor drive circuit 13 made of a relay or the like.

14 is a discharge resistance of the capacitor 10.

In the above configuration, when no document or the like is inserted into the input slot 5, the light pulse emitted from the light emitting element 6 reaches the light receiving element 7, and the light receiving element 7 outputs a pulse output. The pulse output is detected by a detection circuit 9 and a capacitor 10 is charged.

When the potential of the capacitor 10 is higher than the reference voltage 11, the voltage comparator 12 does not output, the motor drive circuit 13 does not operate, and the motor 3 does not rotate.

Next, when paper is inserted into the input port 5, the optical pulse is blocked and the light receiving element 7 does not output a pulse. Therefore, the detection circuit 9 does not output an output, and the charge in the capacitor 10 is discharged through the discharge resistor 14. When the potential of the capacitor 10 becomes lower than the reference voltage 1, the voltage comparator 12 outputs an output, and the motor drive circuit 13 operates to rotate the motor 3.

Then, the paper is shredded, and when the end of the paper passes the detection section, a light pulse reaches the light receiving element 7, and the output of the detection circuit 9 charges the capacitor 10. Then, the potential of the capacitor 10 increases and when it reaches a predetermined value, the motor 3 stops. At this time, the potential of the capacitor 10 gradually increases due to the output impedance of the detection circuit 9, so even if the end of the paper has passed, the motor 3 does not stop immediately, but after a certain period of time has elapsed.

Effects of the Invention As is clear from the above embodiments, the present invention provides a light emitting element and a light receiving element between the drip inlet, drives the light emitting element with a pulse, and detects the light pulse emitted at this time. This prevents malfunctions caused by external light. Furthermore, by charging the capacitor with the output of the detection circuit, the motor can continue to rotate for a suitable period of time even when the end of the paper passes through the detection section, and no paper remains.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of a document shredding machine employing an embodiment of the present invention, FIG. 2 is a sectional view, FIG. 3 is a sectional view of essential parts, and FIG. 4 is a circuit diagram. 4... Motor, 5... Inlet, 6... Light emitting element, 7... Light receiving element, 9... Detection circuit, 10...
Capacitor, 12... Voltage comparator, 13... Drive circuit.

Claims (1)

[Claims] 1. A light-emitting element and a light-receiving element that are driven by pulses of a constant period are installed across the document input slot, the output of this light-receiving element is connected to a detection circuit to detect the pulse, and the output of the detection circuit is connected to a capacitor. connection,
This document shredding machine is configured to compare the potential of the capacitor with a reference voltage using a voltage comparator, connect the output of this voltage comparator to a motor drive circuit, and control the motor.