JP2511914Y2 - Shuretsuda - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of Industrial Use The present invention relates to control of an electric motor in a shredder for shredding documents and the like.

(2) Conventional Technology In shredding operation using a shredder, if the number of unnecessary documents is large, the output of the electric motor is exceeded and the electric motor is restrained and stopped, and the shredded paper pieces are pinched.

Therefore, it is necessary to return the pinched paper piece by reversing operation.

The operation when the paper is jammed, that is, the motor restraint stop-reverse rotation-stop is performed manually and automatically.

In the automatic case, as a method for detecting a paper jam, the electric motor is conventionally controlled by utilizing the increasing component of the load current of the electric motor. However, the control current value varies depending on each rated output, and it must be adjusted for each product unit so as to be within a predetermined control range due to variations in individual motors and cutters.

On the other hand, although CT is used for current detection, it is difficult to say that the one formed by the laminated core is large in size from the viewpoint of performance and it is not suitable from the viewpoint of cost, so a small and low cost ferrite core type is Although used, this type has a particularly poor frequency characteristic in the high-power section, and as a result, the frequency affects the efficiency of shredding of a paper piece. That is, since the number of shreds is generally proportional to the load current, the characteristic of 60Hz reaches a predetermined secondary output voltage with a load current less than 50Hz as shown in the table in Fig. 4 (a). Is less. As a countermeasure against this, a low output section with a small output difference is used, and this output must be amplified and used by an amplifier.

Also, if a device adjusted by the specified power supply capacity is used in a place with a small power supply capacity, the restraint current of the motor goes below the control current and the normal automatic reverse rotation described above does not occur, the restraint state continues, and the motor burns out. This resulted in the protective device working.

However, if the control current is set to be sufficiently low, the shredding ability of the paper, that is, the number of shredded sheets, is reduced, and shredding efficiency is lowered.

The above-mentioned deficiencies are recognized in the known current adjusting system of the shredder.

(3) Purpose of the Invention In view of the above-mentioned conventional problems, the present invention provides a control device that does not require adjustment work, performs a stable operation, and is not affected by power supply capacity.

(4) Configuration of the Invention The shredder of the present invention is provided with a control unit that operates due to a signal from an overcurrent detection unit provided in the starting circuit of the electric motor, so that an alarm or a warning is issued when the electric motor is stopped (including the time of restraint). The feature is that a corresponding operation such as automatic reverse rotation is performed.

(5) Description of Embodiment One embodiment of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a circuit function block diagram showing the overall control device for controlling a conventional shredder. First, a stable power supply (1) that supplies a stable power supply to various places, a detection unit (2) that detects circuit abnormalities, a rectification circuit (3) that rectifies the detected components, opening and closing of the cutter motor, forward / reverse rotation, and paper waste. Opening / closing part (28) that starts and stops the vibration motor that averages mountains and relay vibration circuit (4), autocut input circuit (5) that detects the autocut of the cutter motor, and output from the pulse drive circuit (6) are waste sensors The waste sensor circuit (9) that sends to the light emitting element of (7), the light receiving element detects the reflected light from the waste, and sends this signal to the waveform shaping circuit (8) to notify the fullness of the waste, paper feed (10), a door (11) and a fixed position (12), each sensor circuit (16) which outputs a signal such as an alarm and a display through an input protection filter circuit (13) after receiving signals from the respective sensors.

In the above circuit configuration, when the paper feed sensor (10) detects the paper feed, the cutter motor is started, operates for a fixed time, and then automatically stops. Here, when the number of sheets of paper inserted is large and the motor is restrained, the detection unit (2) detects the overcurrent,
The cutter motor stops and the pinch paper is ejected and stopped after a certain period of reverse rotation. In addition, when the door is opened during operation, when the waste is full, when the auto-cut works, etc., an alarm or display is used to notify. If the motor does not stop automatically by mistake, the motor will stop due to the auto power off function after a certain period of time. All of these auto timing and fail safe functions are based on the circuit configuration incorporated in the program of the CPU (14). Also, by using the shift register in the serial IO in the CPU as an oscillator in the pulse drive circuit for the waste sensor, a low-capacity CPU
Is covered by.

FIG. 2 is a conventional detailed view and FIG. 3 is a partial detailed view of the present invention. In the figure, (15) is a control section including a CPU, (16) is a sensor section, (17) is a main circuit opening / closing section, (18) is an output adjusting section of the signal, (19) is a motor forward / reverse circuit, ( 20) is a cutter motor, and (21), (22), (23), and (24) are an autocut, a main coil, a starting coil, and a centrifugal switch in the motor, respectively. (25) is an alarm, an operation panel including a display,
(26) is a main circuit, (27) is an auxiliary circuit, and (28) is an opening / closing section including a main circuit opening / closing section and a forward / reverse inverting circuit.

First, in FIG. 2, the sensor section (16) or the operation panel (25)
In response to this signal, the control section (15) controls the forward / reverse inverting circuit (19) and the main circuit opening / closing section (17) to perform normal rotation, stop, reverse rotation, etc. of the motor (20). Normally, the shredder ends in normal rotation and stops when the amount of paper that is less than the proper amount is input, but when the amount of paper that exceeds the motor output (the amount that exceeds the number of shreds guaranteed by the manufacturer) is input, the motor rotation will It stops and enters the restraint state, and the restraint current begins to flow in the main circuit and the starting current begins to flow in the starting circuit.
In the conventional system, the detection current of the main circuit is detected by the detector, and it is sent to the output amplifier through the rectifier circuit. When the input exceeds the set value, it is sent to the controller, and the main circuit switch (17) is connected. The forward / reverse inverting circuit (19) is activated to energize, stop, reverse, and restart the cutter motor.

On the other hand, in the present invention, the current of the starting circuit (27) flowing when restrained is used as a signal, and this signal is sent to the control unit (15) through the rectifier circuit (3) so that the main circuit opening / closing unit (17) and the forward / reverse reversal are performed. The circuit (19) is activated to control the cutter motor as described above. Therefore, the present invention, unlike the conventional method that detects the magnitude of the current, amplifies the output, and sends it to the control unit, is a method that detects the presence or absence of the current, that is, only the energization and de-energization. Amplification means that is complicated and amplifies a small output, means for adjusting the sensitivity width generated by a combination of parts,
The conventional configuration and means such as a voltage determination means for an input of a predetermined value or more are unnecessary.

A CT method, a resistance method, a Hall sensor method, or the like can be used as the detection method of the detection unit (2) in the present invention. It goes without saying that the present invention can be easily used not only in the capacitor-starting type motor described above, but also in the capacitor-starting capacitor-running type by providing a sensitivity that is not detected by the current value during capacitor-running. .

(6) Effects of the Invention Comparing the conventional method shown in FIGS. 2 and 3 with the configuration of the present invention, the conventional method uses the load current of the electric motor as an amount, and therefore, the means and parts for amplifying the minute output are Adjustment means for adjusting the output width due to variations within a predetermined width, voltage determination means for determining that the load current has exceeded a predetermined value, etc. were required. By controlling whether the starting circuit current that comes from the motor configuration itself during operation or current is used as a signal, it can be connected directly to the control unit for control, so the number of components can be deleted easily on the circuit and it is inexpensive. It is possible to provide a miniaturized controller.

[Brief description of drawings]

FIG. 1 is a circuit function block diagram showing an overall control circuit for controlling a conventional type shredder, FIG. 2 is a partial detailed view of a conventional type, FIG. 3 is a circuit diagram showing an embodiment of the present invention, and FIG. (A) is a general frequency characteristic table of ferrite core type CT,
(B) shows the circuit. (1) …… Stabilized power supply, (2) …… Detector, (3) ……
Rectifier circuit, (4) …… Relay drive circuit, (5) …… Autocut input circuit, (6) …… Pulse drive circuit, (7)
…… Scrap sensor, (8) …… Waveform rectification circuit, (9) …… Scrap sensor circuit, (10) …… Paper feed sensor, (11) …… Door sensor, (12) …… Fixed position sensor, ( 13) …… Input protection filter circuit, (14) …… CPU, (15) …… Control section including CPU, (16) …… Sensor section, (17) …… Main circuit opening / closing section,
(18) …… Output adjuster, (19) …… Forward / reverse inverting circuit, (2
0) …… Cutter motor, (21) …… Auto cut, (2
2) …… Main coil, (23) …… Starting coil, (24) ……
Centrifugal switch, (25) …… Operation panel, (26) …… Main circuit, (27) …… Auxiliary circuit, (28) …… Opening / closing section, A …… Load current, H …… High output section, L… … Low output, V …… Secondary output.

Claims (1)

(57) [Scope of utility model registration request] 1. A shredder having a control device for automatically stopping and reversing a circuit when an electric motor is restrained and stopped due to an overload, and provided in a starting circuit of the electric motor when the electric motor is decelerated or stopped due to an overload. A shredder that is provided with a control unit that operates based on the signal of the detection unit, and that causes the circuit to shut off and automatically reverse.