JP2000131330A - Small-sized rotation detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized rotation detector which detects the number of revolutions of such a rotating body that can be maintained and adjusted easily at a low installation cost by utilizing the electric power generated from the rotary generator of the detector and outputs an alarm when the number of revolutions reaches a prescribed value. SOLUTION: A small-sized rotation detector is provided with an input shaft 21 connected to a rotating body 11, a rotary generator 20 attached to the shaft 21, and a power source section 40 which converts the electric power generated from the generator 20 into a direct current by rectifying the electric power. The detector is also provided with a control section 50 which is operated by the electric power supplied from the power source section 40, detects the number of revolutions of the shaft 21 from the output of the generator 20, and issues an output signal when the detected number of revolutions reaches a prescribed value and a casing 20 which integrally houses the shaft 21, generator 20, and sections 40 and 50 in a hermetically sealing state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the number of rotations of a rotating body including a driving drum such as a belt conveyor and the like, and the number of rotations of a rotating body such as a touch roller for detecting the speed of a belt. The present invention relates to a small-sized rotation detecting device that outputs an output signal when the number reaches a number.

[0002]

2. Description of the Related Art Conventionally, a rotation detecting device that outputs an alarm signal when the rotation speed of a rotating body reaches a reference rotation speed is provided with an AC generator that generates electric power in accordance with the rotation of the rotating body. The output power of the machine is converted to a DC output by a power supply unit comprising a rectifier circuit, the rotation speed of the rotating body is calculated according to the voltage level of the DC output, and the calculated value is set to a predetermined rotation speed set by a reference value setting unit. Is provided, and an output signal is output from the control unit when the rotation speed of the rotating body reaches a predetermined rotation speed. In this case, the operating power supply of the control unit composed of an electronic circuit using electronic components is a general-purpose 100V or 2V.
The voltage of the AC power supply such as 00V is lowered by a transformer and rectified by a rectifier circuit, and is made a constant voltage of about 5V by a constant voltage control unit.

[0003]

By the way, in the above-mentioned conventional example, a general-purpose AC power supply is used as an operating power supply for an electronic circuit using electronic components, and wiring is carried out from the AC power supply to a control unit of the rotation detecting device by a cable or the like. When detecting the rotation of the rotating body of a machine installed far from the general-purpose power supply,
As the wiring becomes longer, a transformer and a rectifier circuit must be prepared, which requires a lot of equipment costs. It is conceivable to use a storage battery arranged near the rotation detecting device as an operation power supply of the control unit, but there is a problem that maintenance work is required for exhaustion of the storage battery. The present invention has been made in view of such circumstances, using the power generated by the rotating generator of the rotation detecting device, to detect the number of rotations of the rotating body that maintenance and adjustment work is easy at a low equipment cost, It is an object of the present invention to provide a small-sized rotation detecting device that outputs an alarm when a rotating body reaches a predetermined number of rotations.

[0004]

According to the present invention, there is provided a small-sized rotation detecting device according to the present invention, comprising: an input shaft connected to a rotating body; a rotary generator mounted on the input shaft; A power supply unit that rectifies the generated power and converts it to DC, operates by a power supply supplied from the power supply unit, detects the number of rotations of the input shaft from the output of the rotary generator, and detects the detected number of rotations. It has a control unit that outputs an output signal when the number of rotations reaches a predetermined value, and a casing that integrally stores them in a sealed structure. With such a configuration, the operating power of the control unit that detects the number of rotations of the rotating body and outputs an output signal when the detected number of rotations reaches the predetermined number of rotations is obtained by rectifying the power generated by the rotary generator and converting the DC power to DC power. Since it is obtained from a power supply unit that converts the data into a power supply, there is no need to perform wiring from an external general-purpose power supply with a cable, and there is no need for labor such as maintenance work of the storage battery. Here, the control unit calculates the number of revolutions of the rotating body from the output signal corresponding to the electric power, and issues an alarm signal when the number of revolutions reaches the predetermined number of revolutions in comparison with the predetermined number of revolutions. A detection value processing circuit that outputs a signal, an alarm output unit that outputs a relay operation signal in response to an alarm signal output from the detection value processing circuit, and a constant voltage control unit that controls power output by the power supply unit to a predetermined voltage. And a charging unit for a processing circuit and a charging unit for an alarm that respectively supply the output of the constant voltage control unit to the detection value processing circuit and the alarm output unit as operating power. In this case, a charging unit for a processing circuit and a charging unit for an alarm that separately supply operating power to a detection value processing circuit that outputs an output signal as an alarm signal and an alarm output unit that outputs a relay operation signal are provided. Therefore, even if the output of the alarm output unit fluctuates significantly, the influence on the detection value processing circuit that requires operating power with small voltage ripple is reduced, and the detection accuracy can be maintained high. The control unit may be mounted on a printed circuit board, and the printed circuit board may be mounted on an end of the rotary generator on the side opposite to the input shaft. In this case, since the printed circuit board on which the control unit is mounted is provided at the end on the side opposite to the input shaft of the rotary generator, the distance between the rotary generator and the control unit can be reduced, and adjustment and maintenance of the control unit are performed. Work becomes easy.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is a side sectional view of a small-sized rotation detecting device according to an embodiment of the present invention, FIG. 2 is a front view of a bracket of the small-sized rotation detecting device, and FIG. 3 is a block diagram of the small-sized rotation detecting device. is there.

As shown in FIGS. 1, 2 and 3, in a small-sized rotation detecting device 10 according to an embodiment of the present invention, an input shaft 21 of a rotary generator 20 is connected to a rotating body 11, and The generator 20 is provided with an input shaft side bracket 202 inside a cup-shaped housing 201 having an input side opened, and an input is made by a bearing 203 provided on the input shaft side bracket 202 and a bearing 204 provided on a side opposite to the input shaft of the housing 201. The shaft 21 is supported. A field magnet 22 is provided on the input shaft 21, and inside the input shaft side bracket 202,
An armature 23 that opposes the field magnet 22 via the gap G is provided, and an electromagnetic action between the field magnet 22 and the armature 23 causes
Electric power corresponding to the rotation speed of the rotating body 11 is generated. A printed circuit board 30 is mounted on an end of the rotary generator 20 on the side opposite to the input shaft via a bracket 24, and a casing 25 for integrally storing the printed circuit board 30 in a sealed structure.
have. The printed circuit board 30 includes a rotating generator 20.
A power supply unit 40 connected to the armature 23 via a lead wire 26 and provided with a rectification circuit 41 for rectifying the electric power generated by the rotary generator 20 and converting the electric power to DC. And a control unit 50 that detects the number of revolutions of the input shaft 21 from the output of the rotary generator 20 and issues an output signal when the detected number of revolutions reaches a predetermined number of revolutions. As shown in FIG. 3, the control unit 50 includes a detection value processing circuit 51 including an electronic circuit that outputs an alarm signal from an output signal corresponding to the power generated by the rotary generator 20, and an output from the detection value processing circuit 51. And an alarm output unit 52 having a relay terminal 521 connected to a latch relay that outputs a relay operation signal in response to the alarm signal. The control unit 50 further includes a constant voltage control unit 53 that controls the power output from the power supply unit 40 to a predetermined voltage of about 5 V using, for example, a Zener diode, and a detection value processing circuit 51 that outputs the output of the constant voltage control unit 53 to the detection value processing circuit 51. And a processing circuit charging unit 54 and an alarm charging unit 55 that supply the operating power to the alarm output unit 52, respectively. The processing circuit charging section 54 and the alarm charging section 55 have a large-capacity capacitor (for example, 1000 μF), constitute a smoothing circuit, remove rectified voltage ripple of pulsating current, and Absorption of voltage fluctuations due to rotational variations is supplied to the detected value processing circuit 51 and the alarm output unit 52 with stable power. The alarm output unit 52 is ON
Since only the / OFF signal is output, the alarm charging unit 55 does not need to reduce the voltage ripple as compared with the processing circuit charging unit 54. The detection value processing circuit 51
A rotation speed calculation unit 511 for calculating the rotation speed of the rotating body 11 from an output signal corresponding to the power output from the power supply unit 40, and a reference value setting unit 5 for setting a predetermined rotation speed by a digital switch
12, a hysteresis setting unit 513 for preventing chattering of the alarm output unit 52, and an output signal of the reference value setting unit 512 and an output signal of the rotation speed calculation unit 511. Central control unit 5 that outputs signals
14 and a reset unit 515 for deleting the alarm signal stored in the central control unit 514.

Here, the operation of the small rotation detecting device 10 will be described. The rotation speed N1 of the rotating body 11 is, for example, 1000
In the case where an alarm is output when the rotation speed becomes higher than the RPM, the reference value setting unit 512 sets the predetermined rotation speed to 1000.
The central control unit 5 sets the reference voltage level corresponding to the RPM.
Set to 14. In this state, the rotating body 11 is, for example, 96
When rotating at 0 RPM, the rotating generator 20
Generates power corresponding to 960 RPM, and inputs DC power of, for example, 8 V to the constant voltage control unit 53 via the power supply unit 40. The constant voltage control unit 53 outputs an output voltage of, for example, 5 V, which is the operating voltage of the electronic circuit. Is generated and input to the processing circuit charging unit 54 and the alarm charging unit 55. The processing circuit charging section 54 and the alarm charging section 55 include a detection value processing circuit 51 and an alarm output section 52.
Is input as operating power with small voltage ripple. Further, when the power generated by the rotary generator 20 is rectified by the power supply unit 40 and input to the rotation speed calculation unit 511, the output voltage level and the reference voltage level corresponding to 960 RPM calculated by the rotation speed calculation unit 511 are changed. The comparison is performed by the central control unit 514. When the rotation speed of the rotating body 11 increases from 960 RPM, the output voltage level gradually increases. Output voltage level is 1
When the reference voltage level corresponding to 000 RPM is reached, the central control unit 514 outputs an alarm signal to the alarm output unit 52,
For example, a relay operation signal for decelerating the rotating body 11 is output via the relay terminal 521. As a result, the rotating body 11 decelerates, and a fluctuation allowable value set by the hysteresis setting unit 513 to prevent chattering, for example, 1000 RPM
5% down to 950 RPM, the central control unit 5
At 14, an alarm signal is output to the alarm output unit 52 by comparing the output voltage level with the reference voltage level, and a relay operation signal for increasing the speed of the rotating body 11 is output via the relay terminal 521.

With such a configuration, the operating power of the control unit 50, which is an electronic circuit that generates an output signal when the rotation speed of the rotating body 11 reaches a predetermined rotation speed, rectifies the power generated by the rotary generator 20. Power supply 4 to convert to DC
Since it is obtained from 0, there is no need to wire with a cable from an external general-purpose power supply, and there is no need for maintenance work for the storage battery. Also, a processing circuit charging unit 54 that supplies operating power to a detection value processing circuit 51 that outputs an output signal as an alarm signal and an alarm charging unit 55 that supplies operating power to an alarm output unit 52 are separately provided. Therefore, even if the output of the alarm output unit 52 largely fluctuates, the influence on the detection value processing circuit 51 that requires operating power having a smaller voltage ripple than the alarm output unit 52 is reduced, and the detection accuracy is increased. Can be maintained. Also,
The printed circuit board 30 on which the control unit 50 is mounted is connected to the rotary generator 2
0 at the end on the side opposite to the input shaft.
The distance between the control unit 50 and the control unit 50 can be reduced, and adjustment and maintenance work of the control unit 50 become easy.

[0009]

According to the small rotation detecting device according to the first to third aspects, when the rotation speed of the rotating body reaches a predetermined rotation speed, the operating power of the control unit for generating an output signal is generated by the rotary generator. Is obtained from the power supply that rectifies and converts it to direct current.Therefore, there is no need to wire with a cable from an external general-purpose power supply, making it possible to reduce equipment costs and save time for storage battery maintenance and adjustment work. Also, maintenance costs can be reduced. In particular, claim 2
In the small-sized rotation detecting device described above, a charging unit for a processing circuit and a warning unit for separately supplying operating power to a detection value processing circuit that outputs an output signal as an alarm signal and an alarm output unit that outputs a relay operation signal. Since the charging unit is provided, even if the output of the alarm output unit fluctuates greatly, the influence on the detection value processing circuit that requires the operation power with small voltage ripple is reduced, and the detection accuracy can be maintained high. Thus, a high-quality small-sized rotation detecting device can be provided. In the small-sized rotation detecting device according to the third aspect, since the printed circuit board on which the control unit is mounted is provided at the end on the side opposite to the input shaft of the rotary generator, the distance between the rotary generator and the control unit is short, Therefore, it is possible to reduce the length of the wiring to the control unit and the entire length of the rotation detection device, and to facilitate the adjustment and maintenance work of the control unit, thereby providing a compact and inexpensive small rotation detection device.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a small-sized rotation detecting device according to an embodiment of the present invention.

FIG. 2 is a front view of a bracket of the small-sized rotation detecting device according to the embodiment of the present invention.

FIG. 3 is a block diagram of a small rotation detecting device according to one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Small rotation detection apparatus 11 Rotating body 20 Rotary generator 21 Input shaft 22 Field magnet 23 Armature 24 Bracket 25 Casing 26 Lead wire 30 Printed circuit board 40 Power supply unit 41 Rectifier circuit 50 Control unit 51 Detected value processing circuit 52 Alarm output unit 53 Constant voltage control unit 54 Charging unit for processing circuit 55 Charging unit for alarm 201 Housing 202 Input shaft side bracket 203 Bearing 204 Bearing 511 Rotation speed calculation unit 512 Reference value setting unit 513 Hysteresis setting unit 514 Central control unit 515 Reset unit 521 relay terminal

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[Procedure amendment]

[Submission date] September 29, 1999 (1999.9.2)
9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] Small rotation detection device

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the number of rotations of a rotating body including a driving drum such as a belt conveyor and the like, and the number of rotations of a rotating body such as a touch roller for detecting the speed of a belt. The present invention relates to a small-sized rotation detecting device that outputs an output signal when the number reaches a number.

[0002]

2. Description of the Related Art Conventionally, a rotation detecting device that outputs an alarm signal when the rotation speed of a rotating body reaches a reference rotation speed is provided with an AC generator that generates electric power in accordance with the rotation of the rotating body. The output power of the machine is converted to a DC output by a power supply unit comprising a rectifier circuit, the rotation speed of the rotating body is calculated according to the voltage level of the DC output, and the calculated value is set to a predetermined rotation speed set by a reference value setting unit. Is provided, and an output signal is output from the control unit when the rotation speed of the rotating body reaches a predetermined rotation speed. In this case, the operating power supply of the control unit composed of an electronic circuit using electronic components is a general-purpose 100V or 2V.
The voltage of the AC power supply such as 00V is lowered by a transformer and rectified by a rectifier circuit, and is made a constant voltage of about 5V by a constant voltage control unit.

[0003]

By the way, in the above-mentioned conventional example, a general-purpose AC power supply is used as an operating power supply for an electronic circuit using electronic components, and wiring is carried out from the AC power supply to a control unit of the rotation detecting device by a cable or the like. When detecting the rotation of the rotating body of a machine installed far from the general-purpose power supply,
As the wiring becomes longer, a transformer and a rectifier circuit must be prepared, which requires a lot of equipment costs. It is conceivable to use a storage battery arranged near the rotation detecting device as an operation power supply of the control unit, but there is a problem that maintenance work is required for exhaustion of the storage battery. The present invention has been made in view of such circumstances, using the power generated by the rotating generator of the rotation detecting device, to detect the number of rotations of the rotating body that maintenance and adjustment work is easy at a low equipment cost, It is an object of the present invention to provide a small-sized rotation detecting device that outputs an alarm when a rotating body reaches a predetermined number of rotations.

[0004]

According to the present invention, there is provided a small-sized rotation detecting apparatus according to the present invention, comprising: an input shaft connected to a rotating body; a rotary generator mounted on the input shaft; A power supply unit that rectifies and converts the generated power into a direct current, and operates by a power supply supplied from the power supply unit, and detects the rotation speed of the input shaft from the output of the rotary generator, and detects the detected rotation speed. Has a control unit for outputting an output signal when the number of rotations reaches a predetermined number, and a casing for accommodating them integrally in a sealed structure, and the control unit is mounted on a printed circuit board, and the printed circuit board is rotated. It is arranged at the end on the side opposite to the input shaft of the generator. With such a configuration, the operating power of the control unit that detects the number of rotations of the rotating body and outputs an output signal when the detected number of rotations reaches the predetermined number of rotations is obtained by rectifying the power generated by the rotary generator and converting the DC power to DC power. Since it is obtained from a power supply unit that converts the data into a power supply, there is no need to perform wiring from an external general-purpose power supply with a cable, and there is no need for labor such as maintenance work of the storage battery. Since the printed circuit board on which the control unit is mounted is provided at the end of the rotary generator on the side opposite to the input shaft, the distance between the rotary generator and the control unit can be reduced, and adjustment and maintenance work of the control unit is performed. Becomes easier. Here, the control unit calculates the number of revolutions of the rotating body from the output signal corresponding to the electric power, and issues an alarm signal when the number of revolutions reaches the predetermined number of revolutions in comparison with the predetermined number of revolutions. A detection value processing circuit that outputs a signal, an alarm output unit that outputs a relay operation signal in response to an alarm signal output from the detection value processing circuit, and a constant voltage control unit that controls power output by the power supply unit to a predetermined voltage. And a charging unit for a processing circuit and a charging unit for an alarm that respectively supply the output of the constant voltage control unit to the detection value processing circuit and the alarm output unit as operating power. In this case, a charging unit for a processing circuit and a charging unit for an alarm that separately supply operating power to a detection value processing circuit that outputs an output signal as an alarm signal and an alarm output unit that outputs a relay operation signal are provided. Therefore, even if the output of the alarm output unit fluctuates significantly, the influence on the detection value processing circuit that requires operating power with small voltage ripple is reduced, and the detection accuracy can be maintained high.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is a side sectional view of a small-sized rotation detecting device according to an embodiment of the present invention, FIG. 2 is a front view of a bracket of the small-sized rotation detecting device, and FIG. 3 is a block diagram of the small-sized rotation detecting device. is there.

As shown in FIGS. 1, 2 and 3, in a small-sized rotation detecting device 10 according to an embodiment of the present invention, an input shaft 21 of a rotary generator 20 is connected to a rotating body 11, and The generator 20 is provided with an input shaft side bracket 202 inside a cup-shaped housing 201 having an input side opened, and an input is made by a bearing 203 provided on the input shaft side bracket 202 and a bearing 204 provided on a side opposite to the input shaft of the housing 201. The shaft 21 is supported. A field magnet 22 is provided on the input shaft 21, and inside the input shaft side bracket 202,
An armature 23 that opposes the field magnet 22 via the gap G is provided, and an electromagnetic action between the field magnet 22 and the armature 23 causes
Electric power corresponding to the rotation speed of the rotating body 11 is generated. A printed circuit board 30 is mounted on an end of the rotary generator 20 on the side opposite to the input shaft via a bracket 24, and a casing 25 for integrally storing the printed circuit board 30 in a sealed structure.
have. The printed circuit board 30 includes a rotating generator 20.
A power supply unit 40 connected to the armature 23 via a lead wire 26 and provided with a rectification circuit 41 for rectifying the electric power generated by the rotary generator 20 and converting the electric power to DC. And a control unit 50 that detects the number of revolutions of the input shaft 21 from the output of the rotary generator 20 and issues an output signal when the detected number of revolutions reaches a predetermined number of revolutions. As shown in FIG. 3, the control unit 50 includes a detection value processing circuit 51 including an electronic circuit that outputs an alarm signal from an output signal corresponding to the power generated by the rotary generator 20, and an output from the detection value processing circuit 51. And an alarm output unit 52 having a relay terminal 521 connected to a latch relay that outputs a relay operation signal in response to the alarm signal. The control unit 50 further includes a constant voltage control unit 53 that controls the power output from the power supply unit 40 to a predetermined voltage of about 5 V using, for example, a Zener diode, and a detection value processing circuit 51 that outputs the output of the constant voltage control unit 53 to the detection value processing circuit 51. And a processing circuit charging unit 54 and an alarm charging unit 55 that supply the operating power to the alarm output unit 52, respectively. The processing circuit charging section 54 and the alarm charging section 55 have a large-capacity capacitor (for example, 1000 μF), constitute a smoothing circuit, remove rectified voltage ripple of pulsating current, and Absorption of voltage fluctuations due to rotational variations is supplied to the detected value processing circuit 51 and the alarm output unit 52 with stable power. The alarm output unit 52 is ON
Since only the / OFF signal is output, the alarm charging unit 55 does not need to reduce the voltage ripple as compared with the processing circuit charging unit 54. The detection value processing circuit 51
A rotation speed calculation unit 511 for calculating the rotation speed of the rotating body 11 from an output signal corresponding to the power output from the power supply unit 40, and a reference value setting unit 5 for setting a predetermined rotation speed by a digital switch
12, a hysteresis setting unit 513 for preventing chattering of the alarm output unit 52, and an output signal of the reference value setting unit 512 and an output signal of the rotation speed calculation unit 511. Central control unit 5 that outputs signals
14 and a reset unit 515 for deleting the alarm signal stored in the central control unit 514.

Here, the operation of the small rotation detecting device 10 will be described. The rotation speed N1 of the rotating body 11 is, for example, 1000
In the case where an alarm is output when the rotation speed becomes higher than the RPM, the reference value setting unit 512 sets the predetermined rotation speed to 1000.
The central control unit 5 sets the reference voltage level corresponding to the RPM.
Set to 14. In this state, the rotating body 11 is, for example, 96
When rotating at 0 RPM, the rotating generator 20
Generates electric power corresponding to 960 RPM, and inputs DC power of, for example, 8 V to the constant voltage control unit 53 via the power supply unit 40. Is generated and input to the processing circuit charging unit 54 and the alarm charging unit 55. The processing circuit charging section 54 and the alarm charging section 55 include a detection value processing circuit 51 and an alarm output section 52.
Is input as operating power with small voltage ripple. Further, when the power generated by the rotary generator 20 is rectified by the power supply unit 40 and input to the rotation speed calculation unit 511, the output voltage level and the reference voltage level corresponding to 960 RPM calculated by the rotation speed calculation unit 511 are changed. The comparison is performed by the central control unit 514. When the rotation speed of the rotating body 11 increases from 960 RPM, the output voltage level gradually increases. Output voltage level is 1
When the reference voltage level corresponding to 000 RPM is reached, the central control unit 514 outputs an alarm signal to the alarm output unit 52,
For example, a relay operation signal for decelerating the rotating body 11 is output via the relay terminal 521. As a result, the rotating body 11 decelerates, and a fluctuation allowable value set by the hysteresis setting unit 513 to prevent chattering, for example, 1000 RPM
5% down to 950 RPM, the central control unit 5
At 14, an alarm signal is output to the alarm output unit 52 by comparing the output voltage level with the reference voltage level, and a relay operation signal for increasing the speed of the rotating body 11 is output via the relay terminal 521.

With such a configuration, the operating power of the control unit 50, which is an electronic circuit that generates an output signal when the rotation speed of the rotating body 11 reaches a predetermined rotation speed, rectifies the power generated by the rotary generator 20. Power supply 4 to convert to DC
Since it is obtained from 0, there is no need to wire with a cable from an external general-purpose power supply, and there is no need for maintenance work for the storage battery. Also, a processing circuit charging unit 54 that supplies operating power to a detection value processing circuit 51 that outputs an output signal as an alarm signal and an alarm charging unit 55 that supplies operating power to an alarm output unit 52 are separately provided. Therefore, even if the output of the alarm output unit 52 largely fluctuates, the influence on the detection value processing circuit 51 that requires operating power having a smaller voltage ripple than the alarm output unit 52 is reduced, and the detection accuracy is increased. Can be maintained. Also,
The printed circuit board 30 on which the control unit 50 is mounted is connected to the rotary generator 2
0 at the end on the side opposite to the input shaft.
The distance between the control unit 50 and the control unit 50 can be reduced, and adjustment and maintenance work of the control unit 50 become easy.

[0009]

According to the first and second aspects of the present invention, when the rotation speed of the rotating body reaches a predetermined rotation speed, the rotating generator generates the operating power of the control unit for generating an output signal. Is obtained from the power supply that rectifies and converts it to direct current.Therefore, there is no need to wire with a cable from an external general-purpose power supply, making it possible to reduce equipment costs and save time for storage battery maintenance and adjustment work. Also, maintenance costs can be reduced. Also, since the printed circuit board on which the control unit is mounted is provided at the end on the side opposite to the input shaft of the rotary generator, the distance between the rotary generator and the control unit is short. The whole length can be shortened, and adjustment and maintenance work of the control unit become easy, so that a compact and inexpensive small-sized rotation detecting device can be provided. In particular, in the small rotation detecting device according to the second aspect, a charge for a processing circuit that separately supplies operating power to a detection value processing circuit that outputs an output signal as an alarm signal and an alarm output unit that outputs a relay operation signal. Since the charging unit and the charging unit for alarm are provided, even if the output of the alarm output unit fluctuates greatly, the influence on the detection value processing circuit which requires the operating power with small voltage ripple is reduced, and the detection accuracy is improved. It can be maintained at a high level, and a high-quality compact rotation detecting device can be provided.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a small-sized rotation detecting device according to an embodiment of the present invention.

FIG. 2 is a front view of a bracket of the small-sized rotation detecting device according to the embodiment of the present invention.

FIG. 3 is a block diagram of a small rotation detecting device according to one embodiment of the present invention.

[Description of References] 10: small rotation detection device, 11: rotating body, 20: rotating generator, 21: input shaft, 22: field magnet, 23: armature,
24: bracket, 25: casing, 26: lead wire, 30: printed circuit board, 40: power supply unit, 41: rectifying circuit, 50: control unit, 51: detection value processing circuit, 52: alarm output unit, 53: constant voltage Control unit, 54: charging unit for processing circuit, 55: charging unit for alarm, 201: housing, 202: input shaft side bracket, 203: bearing,
204: bearing, 511: rotation speed calculation unit, 512: reference value setting unit, 513: hysteresis setting unit, 514: central control unit, 515: reset unit, 521: relay terminal

Claims (3)

[Claims] 1. An input shaft connected to a rotating body, a rotary generator mounted on the input shaft, a power supply unit for rectifying electric power generated by the rotary generator and converting it to DC, A control unit that is operated by a power supplied from the unit, detects a rotation speed of the input shaft from an output of the rotary generator, and outputs an output signal when the detected rotation speed reaches a predetermined rotation speed; And a casing accommodating the rotation in a closed structure. 2. The small rotation detection device according to claim 1, wherein the control unit calculates a rotation speed of the rotator from an output signal corresponding to the electric power, and compares the rotation speed with the predetermined rotation speed. A detection value processing circuit that outputs an alarm signal when the predetermined rotation speed is reached, an alarm output unit that outputs a relay operation signal in response to an alarm signal output from the detection value processing circuit, and the power supply unit. A constant voltage control unit for controlling the output power to a predetermined voltage; a processing circuit charging unit and an alarm charge for supplying the output of the constant voltage control unit to the detection value processing circuit and the alarm output unit as operating power, respectively. A small rotation detection device, comprising: 3. The small-sized rotation detecting device according to claim 1, wherein the control unit is mounted on a printed circuit board, and the printed circuit board is mounted on an end of the rotary generator on the side opposite to the input shaft. A small rotation detector.