JP2000340423A - Power supply equipment for sorting conveyer provided with electromagnetic coil type switching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the responsibility while preventing the burning or insulation deterioration of an electromagnetic coil by driving a MOSFET through a driving circuit by an excitation signal produced by a control circuit and a PWM circuit, and controlling the on/off and the exciting voltage of the electromagnetic coil. SOLUTION: When the input L1 (27) or L2 (28) is turned on, a pulse signal is sent to a PWM circuit 24, where a wide width pulse is produced for a specified period of time. Then, the pulse-modulated voltage is applied to the gate of a MOSFET 14 through a control circuit 23 and a driving circuit 19. The pulse-modulated voltage is then applied to an electromagnetic coil 17 or 18 for a specified period of time. Overrated excessive exciting current which is caused to flow in the direction from a middle point LA to a middle point LB or from a middle point LC to the middle point LB and commutated current which is caused to flow from the electromagnetic coil 17 or 18 through a diode and a MOSFET 11 or 15 generate large magnetomotive force to suppress the generation of heat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for a sorting conveyor provided with an electromagnetic coil type switching device for sorting moving shoes of a slide shoe type sorting conveyor using an electromagnetic coil.

[0002]

2. Description of the Related Art A conventional sorting apparatus is required to be quiet, have a high processing capacity, and have a long machine life. As a method for solving this, a method using an electromagnetic coil is disclosed in Japanese Unexamined Patent Publication No. 6-227649 and Japanese Utility Model Laid-Open No.
3, disclosed in Japanese Utility Model Laid-Open No. 6-033836. In this method, the power supply is generally sorted by applying a voltage higher than the rated voltage of the electromagnetic coil in order to increase the response of the electromagnetic coil. However, there is a problem that heat generation causes burnout and insulation deterioration, and a method of dispersing heat generation using two electromagnetic coils is disclosed in Japanese Utility Model Laid-Open No. 7-008326.

[0003]

In the case of sorting with a single power supply, a constant high voltage is applied to the electromagnetic coil until the sorting switch is turned on and the slide shoe is completely moved by the electromagnetic coil. The heat generated by the electromagnetic coil may cause burning or insulation deterioration. Therefore, although a method of dispersing heat generation by alternately energizing two switches by using two electromagnetic coils for one switch is disclosed in Japanese Utility Model Application Laid-Open No. 7-008326, the size of the electromagnetic coil is increased. Further, if the variation of the electromagnetic coil occurs, the stability of the sorting operation becomes poor, and the control becomes complicated, which leads to an increase in cost.

In the case of sorting with a single power supply, a counter electromotive voltage is generated from the electromagnetic coil after the sorting switch is turned off. As this processing, there is a method in which a commutation diode is inserted into both ends of the electromagnetic coil for processing. However, the commutation current is consumed by the electromagnetic coil, and the demagnetization time of the residual magnetism of the electromagnetic coil is extended. If the speed of the sorting conveyor increases in this state, the next slide shoe may be sucked by the influence of the residual magnetism and an erroneous sorting operation may occur even though the power to the electromagnetic coil is turned off. In addition, when the varistor is placed at both ends of the coil and the speed of the sorting conveyer is increased, the varistor may generate heat or burn out when the number of on / off operations of the sorting switch increases. With the above method, increasing the sorting speed is almost at its limit. The present invention has been made to eliminate these disadvantages.

[0005]

A first branch line 8 is provided between a positive power supply line 6 and a negative power supply line 7 and its middle point is set at LA.
The OSFET 11 is connected, and the diode 12 is connected between the minus power supply line 7 and the midpoint LA.

A second branch line 9 is provided in parallel with the second branch line 9, and the midpoint of the second branch line 9 is LB. A diode 13 is connected between the positive power supply line 6 and the midpoint LB.
The MOSFET 14 is connected between B.

Further, a third branch line 10 is provided in parallel, the middle point of which is set to LC, a MOSFET 15 is connected between the plus power supply line 6 and the middle point LC, and a diode 16 is connected between the minus power supply line 7 and the middle point LC. .

An electromagnetic coil 17 is connected between the middle points LA and LB, and an electromagnetic coil 18 is connected between the middle points LB and LC.

A drive circuit 19 is connected to the gates of the MOSFETs 11, 14, and 15, and
The drive circuit 19 of T14 is connected to the control circuit 23 and the pulse width modulation circuit 24 via a line 21.

The drive circuit 19 for the MOSFET 11
Is connected to the on / off control means of the control circuit 23 through a line 20.

A drive circuit 19 for the MOSFET 15
Is connected to the on / off control means of the control circuit 23 through a line 22.

An input L1 (27) and an input L2 (28) are input to the control circuit 23 as inputs of the on / off control means.
Is provided.

A current detector 5 for detecting a current flowing between the positive power supply line 6 and the negative power supply line 7 is provided, and receives the detected data and the ON / OFF timing data from the control circuit 23 to receive the data of the electromagnetic coils 17 and 18. A disconnection determination circuit 25 having a function of determining disconnection is provided.

A voltage detector 4 for detecting the voltage between the positive power supply line 6 and the negative power supply line 7 is provided. The detected data is compared with a fundamental wave pulse width data table to calculate and excite the electromagnetic coils 17 and 18. A pulse width modulation circuit having a function of stabilizing a voltage is provided.

A current detector 5 for detecting a current flowing between the positive power supply line 6 and the negative power supply line 7 is provided, and a function of comparing the detected data with reference value data to prevent disconnection and insulation deterioration due to heat generation of the coil. And a protection circuit 26 having protection against overcurrent when the electromagnetic coil or element is short-circuited. The present invention is a power supply device for a sorting conveyor provided with an electromagnetic coil type switching device having the above-described configuration.

[0016]

Embodiments of the present invention will be described below. In FIG. 1, a bridge type rectifier 2 is connected to a commercial power supply voltage 1. The capacitor 3 is connected between a positive power line 6 and a negative power line 7 from the bridge rectifier 2.

The positive power supply line 6 is connected to one of the voltage detector 4, the current detector 5, the drains of the MOSFETs 11 and 15, and the cathode of the diode 13.

The negative power supply line 7 includes a voltage detector 4
On the other hand, the anode side of the diodes 12 and 16 and the MO
The source side of the SFET 14 is connected.

The sources of the MOSFETs 11 and 15 are connected to the cathodes of the diodes 12 and 16, respectively. The anode side of the diode 13 is connected to the drain side of the MOSFET 14.

The electromagnetic coil 17 is connected to a middle point LA where the source side of the MOSFET 11 and the cathode side of the diode 12 are connected, and the other one is a middle point LB where the anode side of the diode 13 and the drain side of the MOSFET 14 are connected. It is connected to the.

The electromagnetic coil 18 is connected to a midpoint LC where the source side of the MOSFET 15 and the cathode side of the diode 16 are connected, and the other one is a midpoint LB where the anode side of the diode 13 and the drain side of the MOSFET 14 are connected. It is connected to the.

The gates of the MOSFETs 11 and 15 are connected to on / off control means of a control circuit 23 by a drive circuit 19 and lines 20 and 22. MOSFE
The gate of T14 is connected to a control circuit 23 and a pulse width modulation circuit 24 via a drive circuit 19 and a line 21.

The pulse width modulation circuit 24 is connected to the output of the voltage detector 4 and the control circuit 23.

In the above configuration, the MOSFETs 11, 1
When the input L1 (27) is turned on while the terminals 4 and 15 are off, on / off control means is executed by the control circuit 23, an on voltage is applied to the gate of the MOSFET 11 via the drive circuit 19, and the MOSFET 11 is turned on. Become.

When the input L1 (27) is turned on, a pulse generation signal is sent to the pulse width modulation circuit 24, and this signal is used as a trigger to generate a pulse P1 having a wide width for a predetermined time in the pulse width modulation circuit 24. And a pulse modulation voltage is applied to the gate of the MOSFET 14 via the drive circuit 19.

The above-described pulse-modulated voltage is applied to the electromagnetic coil 17 for a certain period of time, and an over-excitation current exceeding the rating flowing in the direction from the midpoint LA to the midpoint LB; A large magnetomotive force is generated by the flowing current, and the suction time is shortened.

Thereafter, the pulse P2 is generated by the pulse width modulation circuit 24 until the input L1 (27) is turned off, and the MOSFE is transmitted from the control circuit 23 through the drive circuit 19.
A pulse modulation voltage is applied to the gate of T14.

The above-described pulse-modulated voltage is applied to the electromagnetic coil 17, and the rated exciting current flowing in the direction from the middle point LA to the middle point LB, and the commutation current flowing from the electromagnetic coil 17 through the diode 13 and the MOSFET 11. , A magnetomotive force sufficient to maintain the holding force is generated. This reduces heat generation.

FIG. 3 shows the waveforms of the pulses P1 and P2 output from the pulse width modulation circuit.

The current flowing through the electromagnetic coil is MOSFET
14 is determined by the ratio of the exciting current flowing in the direction from the midpoint LA to the midpoint LB according to the on-pulse width of 14 and the commutation current flowing from the electromagnetic coil 17 through the diode 13 and the MOSFET 11 generated by the off-pulse width of the MOSFET 14. Thus, the magnetomotive force can be determined by adjusting the duty ratio of the pulse.

According to this circuit configuration, when the input L1 (27) is turned off, on / off control means is executed by the control circuit 23, and the MOSFET 1 is turned on via the drive circuit 19.
The gate voltage of No. 1 is cut off and the MOSFET 11 is turned off. At the same time, the pulse modulation voltage from the control circuit 23 to the gate of the MOSFET 14 via the drive circuit 19 is cut off.

As a result, the exciting current to the electromagnetic coil 17 is completely cut off, and the back electromotive voltage from the electromagnetic coil 17 becomes
It is rapidly absorbed by the capacitor 3 connected between the positive power line 6 and the negative power line 7 through the diodes 13 and 12. Therefore, the demagnetizing time of the residual magnetism of the electromagnetic coil 17 is shortened, and the opening time is shortened.

The operation timing of both ends LA-LB from the input L1 (27) to the electromagnetic coil 17 is as shown in FIG.

In the above configuration, the MOSFETs 11, 1
When the input L2 (28) is turned on while the terminals 4 and 15 are off, on / off control means is executed by the control circuit 23, and an on voltage is applied to the gate of the MOSFET 15 via the drive circuit 19, and the MOSFET 15 is turned on. Become.

When the input L2 (28) is turned on, a pulse generation signal is sent to the pulse width modulation circuit 24, and this signal is used as a trigger to generate a pulse P1 having a wide width for a predetermined time in the pulse width modulation circuit 24. And a pulse modulation voltage is applied to the gate of the MOSFET 14 via the drive circuit 19.

The above-mentioned pulse-modulated voltage is applied to the electromagnetic coil 18 for a certain period of time, and an over-excitation current exceeding the rating flowing in the direction from the midpoint LC to the midpoint LB and a current flowing from the electromagnetic coil 18 through the diode 13 and MOSFET 15 A large magnetomotive force is generated by the flowing current, and the suction time is shortened.

Thereafter, the pulse P2 is generated by the pulse width modulation circuit 24 until the input L2 (28) is turned off, and the MOSFE is transmitted from the control circuit 23 through the drive circuit 19.
A pulse modulation voltage is applied to the gate of T15.

The above-mentioned pulse-modulated voltage is applied to the electromagnetic coil 18, and the rated exciting current flowing in the direction from the midpoint LC to the midpoint LB, and the commutation current flowing from the electromagnetic coil 18 through the diode 13 and the MOSFET 15. , A magnetomotive force sufficient to maintain the holding force is generated. This reduces heat generation.

FIG. 3 shows the waveforms of the pulses P1 and P2 output from the pulse width modulation circuit.

The current flowing through the electromagnetic coil is MOSFET
The pulse width modulation circuit 24 and the pulse width modulation circuit 24 determine the ratio of the exciting current flowing in the direction from the midpoint LC to the midpoint LB according to the on pulse width of 14 and the commutation current flowing from the electromagnetic coil 18 through the diode 13 and the MOSFET 15 generated by the off pulse width of the MOSFET 14. Thus, the magnetomotive force can be easily determined by adjusting the duty ratio of the pulse.

With this circuit configuration, when the input L 2 (28) is turned off, the control circuit 23 executes on / off control means, and the MOSFET 1 via the drive circuit 19.
5 is cut off, and the MOSFET 15 is turned off. At the same time, the pulse modulation voltage from the control circuit 23 to the gate of the MOSFET 14 via the drive circuit 19 is cut off.

As a result, the exciting current to the electromagnetic coil 18 is completely cut off, and the back electromotive voltage from the electromagnetic coil 18 becomes
It is rapidly absorbed by the capacitor 3 connected between the positive power supply line 6 and the negative power supply line 7 through the diodes 13 and 16. Therefore, the demagnetization time of the residual magnetism of the electromagnetic coil 18 is shortened, and the open time is shortened.

The operation timing from the input L2 (28) to both ends LA-LB of the electromagnetic coil 18 is as shown in FIG.

The disconnection determination circuit 25 is connected to the positive power supply line 6 through the current detector 5 and a protection circuit 26
To the control circuit 23.

The input L1 (27) of the control circuit 23,
Alternatively, when an ON signal is input to input L2 (28), MOSFE
T14 and the MOSFET 11 or 15 operate, and a current flows between the positive power supply line 6 and the negative power supply line 7 via the electromagnetic coil 17 or 18. This current is compared with the ON signal. If the current does not flow even when the ON signal is input, it is determined that the electromagnetic coils 17 and 18 are disconnected or not connected, and the protection circuit 26 performs an appropriate process.

The contents of the processing are returned as an alarm signal to an external control device for controlling the sorting conveyor power supply through the control circuit 23, and a spare sorting conveyor power supply different from the sorting conveyor power supply is operated instead. To start. By this processing, the sorting operation can be continued without stopping the entire sorting conveyor system.

The pulse width modulation circuit 24 is connected between the positive power line 6 and the negative power line 7 through the voltage detector 4. The voltage between the positive power supply line 6 and the negative power supply line 7 is constantly monitored by the voltage detector 4.

The detected signal is compared with reference value data in the pulse width modulation circuit 24 to generate a pulse modulation voltage signal. When the MOSFET 14 is driven by this signal, it is possible to apply a constant voltage to the electromagnetic coils 17 and 18 which is not affected by the voltage fluctuation between the positive power line 6 and the negative power line 7 due to the fluctuation of the commercial power supply voltage 1. Therefore, when it is considered that the amount of change in the resistance value of the electromagnetic coils 17 and 18 is small, a constant over-excitation current and a rated excitation current which are not affected by the fluctuation of the commercial power supply voltage 1 can flow, and a stable magnetomotive force can be obtained. I can do it.

In the above-mentioned stable state, when the temperature of the electromagnetic coils 17, 18 rises due to energization and the resistance value of the coils increases, the current decreases. This current is detected by the current detector 5 and compared with the data in the protection circuit 26, whereby the temperature rise value is equivalently known to prevent disconnection due to heat generation and insulation deterioration.

The protection circuit 26 is connected to the positive power supply line 6 through the current detector 5. Further, it is connected to the control circuit 23.

The current flowing constantly is monitored by the current detector 5, and the current flowing when the electromagnetic coils 17 and 18 are short-circuited or the element is damaged is compared with the data in the protection circuit 26, and it is determined that the current is overcurrent. In this case, a signal is sent to the control circuit 23, and a signal to the drive circuit 19 is cut off.
The SFETs 11, 14, and 15 are turned off to protect the power supply from damage due to overcurrent.

The contents of the processing are returned as an alarm signal to an external control device for controlling the sorting conveyor power supply through the control circuit 23, and a spare sorting conveyor power supply different from the sorting conveyor power supply is operated instead. To start. By this processing, the sorting operation can be continued without stopping the entire sorting conveyor system.

[0053]

According to the present invention, by applying an appropriate voltage to the electromagnetic coil at an appropriate time, the response can be improved while avoiding the electromagnetic coil from burning or insulation deterioration. In addition, since the residual magnetism at the time of off can be quickly eliminated, the sorting speed can be increased and the operating efficiency of the conveyor system can be increased. According to the present invention, any sort of failure occurs in the sorting conveyor power supply device, and an alarm signal is fed back to an external control device that collectively manages the sorting conveyor power supply, so that another standby device connected to the external control device is used. Since the sorting conveyor power supply device can start operation instead, the entire sorting conveyor system does not stop. Therefore, the sorting operation with high operation efficiency can be continued. According to the configuration of the present invention, conventionally, two MOSFETs and two diodes are required to operate one electromagnetic coil, and when operating two electromagnetic coils as in this case, four MOSFETs are required. Although a MOSFET and four diodes are required, as shown in FIG. 1, by using the MOSFET 14 and the diode 13 from the respective electromagnetic coils, the voltage of the two electromagnetic coils is determined by the three MOSFETs and the three diodes. Control can be performed, and the size and cost of the device can be reduced. With the configuration of the present invention,
A constant voltage that is not affected by fluctuations in the commercial power supply voltage can be applied to the electromagnetic coil. In this state, the temperature rise value can be known equivalently by measuring the current flowing through the electromagnetic coil. This eliminates the need to incorporate a sensor or the like for detecting the temperature inside the electromagnetic coil, thereby reducing the size and cost of the coil.

[Brief description of the drawings]

FIG. 1 is an electronic circuit diagram showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation from an input signal to an end of an electromagnetic coil according to the present invention.

FIG. 3 is a waveform diagram of pulses P1 and P2 output from the pulse width modulation circuit of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Commercial power supply voltage 2 Bridge type rectifier 3 Capacitor 4 Voltage detector 5 Current detector 6 Positive power supply line 7 Negative power supply line 8 First branch line 9 Second branch line 10 Third branch line 11 MOSFET 12 Diode 13 Diode 14 MOSFET 15 MOSFET 16 Diode 17 Electromagnetic coil 18 Electromagnetic coil 19 Drive circuit 20 line 21 line 22 line 23 control circuit 24 pulse width modulation circuit 25 disconnection determination circuit 26 protection circuit 27 input L1 28 input L2

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H730 AA15 AA20 BB11 BB57 CC01 DD04 FD11 FD41 FG05 XX01 XX03 XX11 XX15 XX19 XX22 XX35 XX41 XX42

Claims (4)

[Claims] 1. An input signal to an input L1 (27) and an input L2 (28) causes an excitation signal generated by a control circuit 23 and a pulse width modulation circuit 24 to drive MOSFETs 11, 14, 15 via a drive circuit 19. By controlling the on / off and the excitation voltage of the predetermined electromagnetic coils 17 and 18 to drive them, the magnetomotive force of the electromagnetic coils 17 and 18 is adjusted to improve the responsiveness, and the heat generation of the electromagnetic coils 17 and 18 is suppressed. A power supply device for a sorting conveyor, comprising a switching device of an electromagnetic coil type. 2. A current detector 5 for detecting a current flowing through a positive power line 6 and a negative power line 7 is provided. The current detector 5 receives the detected data and on / off timing data from the control circuit 23, and 1
8 is provided with a disconnection determination circuit 25 having a function of determining disconnection of the electromagnetic coil 17 and 18 to prevent a defective sorting of the conveyor due to the disconnection of the electromagnetic coils 17 and 18. Power supply. 3. A pulse detector having a voltage detector 4 for detecting a voltage between the positive power supply line 6 and the negative power supply line 7, and having a function of comparing the detected data with a fundamental wave pulse width data table. A width modulation circuit 24 is provided;
A power supply device for a sorting conveyor, comprising: a switching device of an electromagnetic coil type, which stabilizes an excitation voltage with respect to an input voltage fluctuation. 4. A function for monitoring a temperature rise state of the electromagnetic coils 17, 18 based on the detected data, wherein the current detector 5 for detecting a current flowing through the positive power supply line 6 and the negative power supply line 7 is provided. A protection circuit 26 having a protection function for the electromagnetic coils 17 and 1 is provided.
3. A power supply device for a sorting conveyor comprising a switching device of the electromagnetic coil type according to claim 2, wherein the power supply device has a function of preventing disconnection due to heat generation of 8 and insulation deterioration.