JPH0787903B2 - Document shredding device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a document shredding device for shredding a document into indecipherable pieces, and particularly to drive control of a shredding cutter or the like.

<Prior Art> In general, a shredding mechanism for shredding a document is composed of a pair of cutter rollers that rotate with each other, or a rotating cutter (such as disclosed in Japanese Utility Model Publication No. 51-45585). There is a combination of a spiral blade) and a fixed cutter.

The shredding device equipped with the shredding mechanism as described above has both the continuous use time (rated time) and the maximum number of simultaneous shredding (maximum shredding torque) in the ability of the shredding motor (driving motor) for driving the cutter, etc. Entrusted. Therefore, the user is using according to the specifications within the range of the ability.

In addition, the conventional document shredding device is equipped with shredding motor protection devices such as protection switches to prevent burnout due to overheating of the shredding motor when shredding beyond the capacity of the shredding motor for a long time. Has been. Therefore, the protection switch is actuated to cut off the power supply to the shredded motor and prevent the shredded motor from overheating.

In addition, as disclosed in Japanese Utility Model Publication No. 54-4143, the alarm thermostat is activated by the overheating of the shredding motor, and the alarm indicator light is turned on to alert the user of the text shredding machine. There are also things.

<Problems to be solved by the invention> Conventionally, since the capacity of the shredding motor is fixed to a constant value, the shredding motor will overheat and the protective device will operate if it is used in a state where the usage conditions by the user do not match. The shredder becomes unusable.

The shredding motor protection device operates at a high temperature, and once it operates, the shredding motor does not start until the temperature drops, and it takes a considerably long time before shredding is possible again, and the shredding work efficiency is improved. There was a problem that it dropped significantly.

Also, in Japanese Utility Model Publication No. 54-4143, the temperature of the shredding motor rises and the echo display device operates only.Since the shredding judgment is left to the user, the user ignores the alarm display device. Alternatively, there is a risk that the number of simultaneous shreds will not be sufficiently reduced and shredding will continue. Then, the shredding motor protection device still operates and the problem that the efficiency of shredding work is significantly reduced cannot be solved.

Moreover, Japanese Patent Publication No. 53-4891 and the like may automatically drive the cutter in the reverse direction when the load exceeds the overload detection level. In this case, even if it is effective in terms of protection, the work will be interrupted midway.

In any case, since the shredding motor has a fixed shredding capability, the usage conditions are determined and the operation is limited to a narrow range, and the efficiency of shredding cannot be improved.

An object of the present invention is to make variable the shredding ability of a shredding motor, widen the conditions of use, and improve the efficiency of shredding work.

<Means for Solving Problems> In the document shredding device of the present invention, a switching circuit for switching the capacity of the capacitor is provided in the drive circuit of the shredding motor for driving the shredding cutter. It is characterized in that the capacity of the capacitor is automatically switched according to the means for detecting the temperature of the cutting motor, and at the same time, the display of the shredding ability is also switched in response to the switching.

<Operation> According to the document shredding device of the present invention, the capacity of the capacitor connected to the shredding motor is switched according to the temperature rise of the shredding motor, so that the output torque of the shredding motor is switched. In particular, if the temperature of the shredding motor becomes high, the power supply is cut off in order to protect the shredding device, especially the motor. The switching is performed by the switching means before the power supply is cut off. Therefore, when the temperature of the shredding motor rises, the output torque is reduced so that the shredding ability is reduced.
This reduces the number of sheets to be shredded,
The temperature rise can be suppressed and the shredding device can be used for a long time. In this way, the shredding operation is not stopped for protection in the middle.

Moreover, since the display is switched in accordance with the shredding capability automatically according to the automatic switching of the shredding capability, it can be understood that the user only needs to insert the amount of paper that can be shredded into the shredded portion. Therefore, it is possible to prevent the state in which the shredding cannot be performed or the motor or the like is damaged by locking the shredding motor by inserting the paper having the capacity or more.

<Embodiment> FIG. 1 is a circuit diagram for driving and controlling a shredding motor for rotating a shredding cutter according to the present invention. The shredding motor 1 is a general AC capacitor motor, and in order to switch shredding capacity, three capacitors 3 _-1 , 3 _-2 , 3 _-3 having different capacities are connected to the winding. Switching means 4 for
Is provided.

The changeover means 4 is a changeover switch arranged in the operation portion as shown in FIG. 3, and the capacitor 3 is provided at each contact of the switch.
_{-1,3 -2} are connected. The capacitor 3 _-3 is connected to the winding 2 of the motor 1. The changeover switch of the changeover means 4 is connected to one of the AC power sources 5 via a forward / reverse switch 8 for controlling the forward or reverse rotation of the motor 1. The winding 3 of the motor 1 is connected to another terminal of the AC power source 5 via an electric contact (protection contact) 6 of the thermal protector and a power-on switch 7. The electric contact 6 is for preventing overheating of the motor 1, for example,
When the motor 1 reaches a predetermined temperature T or higher, the contact is opened.

The terminal A of the switching means 4 is connected to the capacitor 3 _-1 , the terminal B is connected to the capacitor 3 _-2 , and the terminal C is an open terminal. Therefore, if the switching means 4 is switched to the terminal A, the combined capacitance of the capacitors 3 _-1 and 3 _-3 is connected to the winding 2, and if switched to the terminal B, the capacitors 3 _-2 , 3 are connected.
_-3 is connected to the winding, and if it is switched to the terminal C, only the capacitor 3 _-3 is connected to the winding 2. The capacities of the capacitors 3 _-1 , 3 _-2 have a relationship of 3 _-1 > 3 _-2 , and the capacities of the capacitors for the terminals A, B, C are A>B> C.

In this circuit configuration, when the power supply switch 7 is turned on, the shredding motor 1 is shredded according to the amount of the capacitors 3 _-1 , 3 _-2 , 3 _-3 selected by the switching means 4. Driven by. For example, when the terminal A is selected by the switching means 4,
A current i determined by the impedance of the capacitors 3 _-1 , 3 _-3 flows in the circuit. In this case, the current i determines the output torque of the shredding motor 1 and also determines the temperature rise rate. Therefore, each terminal A of the switching means 4,
B and C are in the relationship of A>B> C, and the current for this is i _A
<I _B <i _C (i _A : current from terminal A, i _B : current from terminal B,
i _C : current from terminal C).

The shredding motor 1 shown in FIG. 1 is arranged to drive a shredding cutter as shown in the schematic perspective view and sectional view of the shredding device of FIGS. 2 and 3.

In the document shredding device 10, a shredder portion is constituted by a vertical cutting cutter means 20 and a horizontal cutting cutter means 30. At the bottom of the input port 11 for inputting documents, the vertical cutting means 20
However, a transverse-cutting cutter means 30 is further arranged below it. The document input from the input port 11 is first shredded into a long shape by the action of the vertical cutting cutter means 20, and then cut into a chip shape by the action of the horizontal cutting cutter means 30.
The chips after the shredding are discharged and collected in the shredded waste container 12 arranged at the bottom of the document shredding device 10.

The vertical cutting cutter means 20 is a metal circular blade 2 having a thickness of 1 to 3 mm.
1 and a pair of cutter members in which resin-molded spacers 22 are alternately provided are arranged to face each other. Circular blade 21
The spacers 22 are provided at intervals of about 3 to 8 mm and the circular blades 21 facing each other are brought into contact with each other to rotate, thereby cutting the document into long pieces. In particular, each cutter member is arranged so that the circular blades 21 and the spacers 22 are alternately inserted into the rotationally driven shaft 23 so that the circular blades 21 facing each other come into contact with each other. The circular blade 21 is attached so as to rotate with the rotation of the shaft 23.

The cross-cutting cutter means 30 is composed of a rotary cutter 31 having a spiral blade and a fixed cutter 37 shown in FIGS. In particular, the fixed cutter 37 is rotatably supported by the integrally formed shaft portion 33, and its blade edge is pressed toward the rotary cutter 31 by an urging means (not shown) such as a spring. The configuration is The rotary shaft 23 and the rotary cutter 31 of the circular blade 21 are rotatably provided between the frames 15 and 16 into which the bearings 13 and 14 are press-fitted.

The shredding motor 1 is fixedly arranged on a bottom plate or the like that is a connecting member with the frames 15 and 16, and is a helical gear 41 that is directly connected to the rotating shaft 41 of the motor (integrally formed with the rotating shaft 41).
However, the rotation is transmitted to the helical gear 42. The helical gear 42 is coaxially provided with a normal gear 43, and the rotation is transmitted to the gear 44 via the gear 43. A gear 45 is provided coaxially with the gear 44.
The rotation is transmitted to 46. Furthermore, a gear 47 coaxial with the gear 46
Transmits the rotation to a gear 48 for rotationally driving the circular blade 21. A gear 50 fixed to one end of the shaft 23 of the cutter member on the left side in FIG. 2 meshes with a gear 49 coaxial with the gear 48. The fixed gear 51 meshes.

On the other hand, a gear 52 is further meshed with the gear 46, and the rotation is transmitted to the rotary cutter 31 via a shaft 53 to which the gear 52 is fixed. The shaft 53 is rotatably supported between the frames 15 and 16. Therefore, the gear 52 fixed to one end of the shaft 53 and the transmission gear 54 on the other end of the shaft 53 on the opposite side.
Is stuck. The transmission gear 54 is a rotary cutter.
The shaft 31 is engaged with a drive gear 55 fixed to one end of the cylindrical portion of the rotary cutter 31. Therefore, the rotary cutter
31 rotates in a clockwise direction in the figure with rotation of the shredding motor 1 (rotation in a counterclockwise direction), and the shaft 23 that rotates the circular blade 21 of the vertical cutting cutter mechanism is in the direction of shredding documents. Rotate each.

As described above, the rotational force of the shredding motor 1 is transmitted to both the rotary cutter 31 and both shafts 23 of the vertical cutting cutter member via the rotation transmission means including a large number of gears.

In the document shredding device configured as described above, when the power supply switch 7 arranged on the operation section surface is operated and its contact is turned on, the A and C power supplies 5 are supplied to the shredding motor 1. It As a result, the rotation of the gear 41 formed on the rotary shaft 40 of the shredding motor 1 causes the circular blade 21 and the rotary cutter 31 to rotate via various gears (transmission means).

In this state, when a document is thrown in through the throwing port 11, it is shredded by each of the rotating cutter means, and shredded scraps are stored in the storage portion 12. At this time, the number of shredded sheets that can be shredded by the shredder 10 at the same time is determined by the output torque of the shredding motor 1. The output torque of the shredding motor 1 is determined by the current i flowing through the shredding motor 1. Also, shredder
The time that can be continuously shredded at 10 is determined by the temperature rise of the shredding motor 1. Then, the temperature rise of the shredding motor 1 is also determined by the current i flowing through the shredding motor 1. When the current i increases, the output torque of the shredding motor 1 increases, and the number of sheets that can be shredded by the shredding device 10 at the same time increases.
On the other hand, however, the temperature rise of the shredding motor 1 increases and the time during which the shredding device 10 can continuously shred becomes short. On the contrary, when the current i flowing through the shredding motor 1 becomes smaller, the output torque of the shredding motor 1 decreases and the number of sheets that can be shredded simultaneously by the shredding device 10 decreases. On the other hand, however, the temperature rise of the shredding motor 1 becomes low, and the time that the shredding device 10 can continuously shred becomes long.
The number of sheets that can be shredded at the same time by the shredding device 1 and the time that can be continuously shredded have a relative relationship with respect to the current i in terms of shredding ability.

Therefore, the switching terminal A, which is the switching means 4, according to the usage conditions,
Switch to select either B or C. That is, the switching terminals may be selected so as to meet the usage conditions as shown in Table 1 below.

As described above, if there are few documents to be shredded, the switching terminal C may be selected so that the maximum number of shredded sheets can be increased, and the processing time can be greatly shortened. If a large number of shredded documents are present, the switching terminal A may be selected for continuous use. In this case, the contact 6 of the protection switch does not operate and open due to overheating of the motor 1, and continuous use can be performed.

Since the user of the document shredding device can switch the switching means 4 according to the method of use and the situation of use, the document shredding device can be used under optimum shredding conditions, so that the shredding efficiency can be improved.
Further, the provider of the document shredding device can easily design the shredding device that meets the demands of the user of the shredding device, and it is not necessary to prepare various models, which is advantageous in cost.

When the rotation (normal rotation) of the motor 1 is stopped due to overload or the like, it is necessary to reverse the motor 1 to remove the document. Therefore, by switching the forward / reverse selector switch 6 to the lower contact, the connection position of the capacitor is reversed and the motor 1 is rotated in reverse. This allows the document to be removed.

In the above embodiments, the changeover means 4 is provided by manually providing the changeover switch. However, the changeover means 4 may be changed over according to the temperature rise of the shredding motor 1. FIG. 4 shows an example of a drive circuit showing an example thereof.

In the figure, reference numeral 40 denotes a switching contact forming a switching means, which opens and closes in response to temperature detection by a temperature detection element arranged in the near-field of the shredding motor 1. The switching contact 40 is opened and closed by a temperature detecting means which responds to a signal from a temperature detecting element set to a temperature T ₁ lower than the operating temperature T of the protection contact 6 for preventing overheating, whereby the switching means is operated. I am configuring. For example, at the beginning of the shredding device 10, the shredding motor 1
Is low, and is below the above temperature T ₁ , and in that state,
The contact is closed, and when the temperature rises to T ₁ or higher, the contact opens.

The capacitors 30 _-1 and 30 _-2 are connected in parallel via the switching contact 40, and the capacitors connected in parallel are connected to the winding 2 in parallel. This capacitor 30 _-1 , 3,
The capacities of 0 _-2 may be the same or different.

In the circuit diagram of FIG. 4, when the power supply switch 5 is turned on, the switching contact 40 is closed, and the capacitance of the capacitor becomes a combined capacitance of 30 _-1 and 30 _-2 , and the impedance is reduced. For example, the device 10 operates with the capability of 4c shown in Table 1. Operates in this state, shredding motor 1
When the temperature detecting means detects the temperature T ₁ before the protective contact 6 is activated (opened), the switching contact 40 is opened. As a result, only the capacity of the capacitor 30 _-1 increases, the impedance increases, the output torque of the shredding motor 1 decreases, and the maximum number of shreds also decreases. This state is designed to operate with the ability of 4A shown in Table 1. Therefore, the temperature rise is suppressed and the continuous use time can be extended.

As described above, in the initial state, since the maximum number of shredded sheets is large, a large time reduction can be expected when cutting a small amount of documents, and when cutting a large number of documents, the continuous device 10 is used. Switching is performed in the middle so that the protective contact 6 can be used.
The shredding process can be efficiently performed without operating the above.

Here, the switching means for controlling the opening / closing of the switching contact 40 by detecting the temperature may be formed of, for example, a bimetal or a shape memory alloy whose shape is changed according to the temperature. That is, the contact 40 may be opened and closed by utilizing the change in shape.

Further, in the example of FIG. 4, the capacitance of the capacitor connected to the winding wire 2 of the shredding motor 1 is selected as two types, but a plurality of capacitor capacities can be selectively switched according to a plurality of different temperature detections. Of course, it may be configured. Also,
When the shredding ability of the shredding motor 1 is switched, it is more effective if conditions such as the maximum number of shreds are displayed to the user in response to the switching operation in order to show the ability. That is, when the switching is performed due to the temperature rise, the number of shredded pieces and the like are simultaneously variably switched and displayed. This allows the user to know that the documents corresponding to the number of sheets should be input. However, if the above-mentioned display is not made, the user must insert the same number of sheets as before, and the shredder motor cannot be shredded due to the rotation lock of the shredding motor, and is overheated to activate the protective device. Therefore, the shredding device cannot be used, the use efficiency of the shredding device is reduced, and the shredding work time becomes longer.

<Effect> According to the document shredding device of the present invention, it is possible to use the document shredding device according to the usage situation, and the shredding work can be efficiently performed. In particular, the output torque of the motor is switched so that the protection device does not operate according to the temperature rise, and it is possible to prevent the shredding device from stopping in the middle and falling into an unusable state. Moreover, since the shredding ability is displayed at the same time as the switching, the user can understand that the shredded paper cannot be inserted any more, and thus the work efficiency can be further improved without stopping the shredding device.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an example of drive control of a shredding motor of a shredding device according to the present invention, and FIGS. 2 and 3 are perspective views and sectional views showing an outline of an example of a document shredding device according to the present invention. FIG. 4 is a circuit configuration diagram showing another specific example of the shredding motor according to the present invention. 1: Shredding motor, 2: Winding, 3 _-1 , 3, _-2 , 3 _-3 : Capacitor,
4: Switching means, 40: Switching contact, 30 _-1 , 30 _-2 : Capacitor, 21:
Round blade, 31: rotary cutter.

Claims (1)

[Claims] 1. A document shredding apparatus in which a capacitor is connected to a coil of a motor for driving a shredding mechanism for shredding paper, and the output torque is changed by changing the capacity of the capacitor. Switching means configured to detect the temperature of the shredding motor and change the output torque to change the output torque, and switching to the shredding capacity of the paper corresponding to the output torque according to the switching of the switching means. A document shredding device comprising: display means for displaying.