Safety protection circuit for dual power failure and power supply system

Abstract

The utility model provides a safety protection circuit and a power supply system for dual power outage, the circuit comprises a switching power supply, a safety relay, an emergency stop switch, an interlocking device, a reset switch and at least two contactors, and main contacts of the two contactors are connected in series between an input power supply and a load; the input power supply outputs power signals to the switching power supply, the switching power supply converts the power signals and then outputs the power signals to a power supply loop and an output loop of the safety relay, the safety relay comprises at least two output loops, and the input end of each output loop is connected with the positive electrode of the switching power supply. The output end is connected in series with a control coil of a contactor and then connected with the cathode of the switching power supply; the safety relay further comprises a reset loop and an input loop, the emergency stop switch and the interlocking device are connected in series in the input loop, and the reset switch and the normally closed auxiliary contacts of the two contactors are connected in series in the reset loop. According to the invention, dual power-off control can be realized, and reliable power-off of equipment is ensured.

Description

Technical Field

[0001] This application relates to the technical field of equipment power supply, and particularly to a safety protection circuit and a power supply system for dual power-off. Background Art

[0002] Due to the extremely high cost and huge production stoppage losses of semiconductor equipment, when a semiconductor equipment fails, it is usually necessary for the operator to cut off the power of the equipment as soon as possible after discovering the failure and then power on again after troubleshooting to avoid further expansion of the losses caused by too long power-off time. However, the existing power supply systems usually adopt a single contactor circuit for control. When the single contactor fails, there will be certain dangers in the power-off operation, and in severe cases, it may even endanger the personal safety of the operator. Therefore, safety protection measures for dual power-off should be taken for the power supply systems of some key positions and important equipment to prevent further expansion of losses and even occurrence of personal safety accidents in case of emergencies. Summary of the Utility Model

[0003] In view of this, the main purpose of this application is to provide a safety protection circuit and a power supply system for dual power-off, which realize dual power-off control by setting at least two contactors and a safety relay in the main power supply circuit, avoid equipment damage caused by single contact failure, and ensure reliable power-off of the equipment.

[0004] In the first aspect, this application provides a safety protection circuit for dual power-off, which is arranged between an input power supply and a load. The circuit includes a switching power supply, a safety relay, an emergency stop switch, an interlock device, a reset switch and at least two contactors. The main contacts of the two contactors are connected in series between the input power supply and the load;

[0005] The input power supply outputs a power signal to the switching power supply. The switching power supply converts the power signal and then outputs it to the power supply circuit and the output circuit of the safety relay respectively. The safety relay includes at least two output circuits. The input end of each output circuit is connected to the positive pole of the switching power supply, and the output end is connected to the negative pole of the switching power supply after being connected in series with the control coil of a contactor;

[0006] The safety relay further includes a reset circuit and an input circuit. The emergency stop switch and the interlock device are connected in series in the input circuit. The reset switch and the normally closed auxiliary contacts of the two contactors are connected in series in the reset circuit.

[0007] Optionally, when the emergency stop switch and the interlock device are closed, by pressing the reset switch, the two output circuits of the safety relay respectively output enable signals to control the two contactors to close, so that the input power supply supplies power to the load;

[0008] When the emergency stop switch or the interlock device is disconnected, the two output circuits of the safety relay stop outputting enabling signals, the two contactors are disconnected, and the input power supply stops supplying power to the load.

[0009] As described above, in the present application, a safety relay and at least two contactors are provided between the input power supply and the load, and the emergency stop switch and the interlock device are connected in series to the reset circuit of the safety relay. When the emergency stop switch and the interlock device are both closed, the reset switch can be pressed to enable the safety relay to output an enabling signal to the control coils of the two contactors through its output circuit, controlling the two contactors to close, so that the input power supply supplies power to the load. When a fault occurs, any one of the emergency stop switch and the interlock device can be disconnected to disconnect the input circuit of the safety relay. The output circuit of the safety relay stops outputting the enabling signal. At this time, the two contactors are disconnected, and the input power supply stops supplying power to the load. In the present application, double power-off is achieved by using a safety relay and two contactors, avoiding equipment damage caused by the failure of a single contact and ensuring reliable power-off of the equipment.

[0010] Optionally, the safety relay includes two input circuits, the emergency stop switch and the interlock device respectively adopt double contacts, and the double contacts of the emergency stop switch and the interlock device are respectively connected in series to the two input circuits.

[0011] As described above, the emergency stop switch and the interlock device adopt a double-contact design. When the emergency stop switch or the interlock device is pressed, the two independent contacts can be opened simultaneously, ensuring that the circuit is reliably cut off, effectively avoiding potential safety hazards caused by the failure of a single contact, and ensuring the reliability and stability of the emergency stop switch and the interlock device.

[0012] Optionally, the output circuit of the safety relay includes at least one relay switch.

[0013] As described above, the safety relay forms an output circuit through relay switches. One end of the relay switch is connected to the positive pole of the switching power supply, and the other end is connected to the negative pole of the switching power supply after being connected in series with the control coil of the contactor, thereby forming an output circuit that provides an enabling signal for the contactor.

[0014] Optionally, it further includes a leakage circuit breaker provided at the output end of the input power supply.

[0015] As described above, the input power supply outputs a wide-voltage AC power signal. When there is a leakage, there are relatively large potential safety hazards. By providing a leakage circuit breaker at the output end, it has overload and short-circuit protection functions and can protect personal safety and equipment safety in case of a leakage fault.

[0016] Optionally, it further includes a first circuit breaker provided at the input end of the switching power supply.

[0017] Optionally, it further includes a second circuit breaker disposed at the positive pole of the switching power supply.

[0018] As described above, by providing circuit breakers at the input end and the positive pole of the switching power supply, short - circuit or overload protection can be achieved when a short - circuit or severe overload occurs in the circuit, preventing damage to the safety relay at the back end.

[0019] Optionally, the power signal output by the input power supply is an AC power signal of 200V - 500V, and the switching power supply converts the AC power signal into a DC voltage signal of 24V.

[0020] As described above, the switching power supply converts the wide - voltage AC power signal output by the input power supply to provide a 24V DC voltage signal for devices such as the safety relay and contactor at the back end.

[0021] In a second aspect, the present application provides a power supply system including the above - mentioned safety protection circuit for double power - off.

[0022] As described above, by providing the safety protection circuit for double power - off of the present application in the power supply system, double power - off control of the power supply system can be achieved, preventing equipment damage caused by single - contact failure and ensuring reliable power - off of the equipment.

[0023] These and other aspects of the present application will become more understandable in the following description of the (multiple) embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a circuit diagram of a safety protection circuit for double power - off provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings.

[0026] The embodiment of the present application provides a safety protection circuit for double power - off and a power supply system. Double power - off control is achieved by providing at least two contactors and a safety relay in the main power supply circuit, preventing equipment damage caused by single - contact failure and ensuring reliable power - off of the equipment.

[0027] Such as Figure 1The figure shows a circuit diagram of a safety protection circuit for dual power-off provided by an embodiment of the present application. This safety protection circuit can be specifically used in the power supply system of semiconductor equipment. The safety protection circuit can be arranged between the input power supply and the load of the power supply system. The safety protection circuit includes a switching power supply PS, a safety relay SFC, an emergency stop switch EMO, an interlock device INTERLOCK, a reset switch RESET, and two contactors KM1 and KM2. The main contacts 1-2, 3-4, and 5-6 of the two contactors KM1 and KM2 are connected in series between the input power supply and the load. When the two contactors KM1 and KM2 are closed simultaneously, the input power supply supplies power to the load. When at least one of the two contactors KM1 and KM2 is disconnected, the input power supply stops supplying power to the load.

[0028] Among them, the output terminal of the input power supply is connected to the input terminal of the switching power supply PS through a circuit breaker CB1, which is used to provide a wide-voltage AC power signal to the switching power supply PS. The circuit breaker CB1 can perform open circuit or short circuit protection when a short circuit or serious overload occurs in the circuit, to prevent the subsequent switching power supply PS from being damaged. After converting the AC power signal into a DC power signal, the switching power supply PS outputs it to the power supply circuit A1-A2 and the output circuit of the safety relay SFC respectively. The safety relay SFC includes at least two output circuits, and the two output circuits are respectively realized through relay switches. The relay switch of the first output circuit has an input terminal 13 and an output terminal 14, and the relay switch of the second output circuit has an input terminal 23 and an output terminal 24. The two input terminals 13 and 23 of the two output circuits are connected to the positive pole of the switching power supply PS through a circuit breaker CB2. The two output terminals 14 and 24 of the two output circuits are respectively connected in series with the control coils of a contactor KM1 and KM2 and then connected to the negative pole of the switching power supply PS, which is used to output an enable signal to the control coil to control the contactors KM1 and KM2 to attract.

[0029] The safety relay SFC also includes a reset circuit S12-S34 and two input circuits S11-S12, S21-S22. The emergency stop switch EMO and the interlock device INTERLOCK both adopt a double-contact design and are connected in series in the two input circuits S11-S12, S21-S22. The reset switch RESET and the normally closed auxiliary contacts KM1-1b, KM2-1b of the two contactors KM1 and KM2 are connected in series in the reset circuit.

[0030] In some embodiments, since the input power supply can output an AC power signal in the range of 200V - 500V, the switching power supply PS needs to convert this AC power signal into a DC voltage signal of 24V to supply it to the safety relay SFC at the back end. When there is a leakage at the output end of the input power supply, it is likely to bring greater safety hazards. Based on this, a leakage circuit breaker ELB can be set at the output end of the input power supply. This leakage circuit breaker ELB has overload and short - circuit protection functions and can protect personal safety and equipment safety when a leakage fault occurs.

[0031] Based on the following Figure 1 shown, the working principle of the safety protection circuit for double power - off provided by the embodiments of the present application will be described.

[0032] When the power supply system needs to supply power to the load, close the leakage circuit breaker ELB, the miniature circuit breakers CB1 and CB2. The indicator light of the switching power supply PS and the power indicator light of the safety relay SFC will light up. If the emergency stop switch EMO and the interlock device INTERLOCK are closed simultaneously, by pressing the reset switch RESET, the two output circuits of the safety relay SFC can respectively output enable signals to the control coils of the two contactors KM1 and KM2, controlling the two contactors KM1 and KM2 to close, so that the input power supply supplies power to the load;

[0033] When a fault occurs in the power supply system, by disconnecting any one of the emergency stop switch EMO and the interlock device INTERLOCK, the input circuit of the safety relay SFC can be cut off. The output circuit of the safety relay SFC stops outputting enable signals to the control coils of the contactors KM1 and KM2. At this time, the two contactors KM1 and KM2 are disconnected, and the input power supply can stop supplying power to the load;

[0034] If the fault is eliminated and power supply needs to be restored, by resetting the emergency stop switch EMO and the interlock device INTERLOCK to make the emergency stop switch EMO and the interlock device INTERLOCK closed simultaneously, and then pressing the reset switch RESET again, the two output circuits of the safety relay SFC can re - output enable signals to the control coils of the two contactors KM1 and KM2, controlling the two contactors KM1 and KM2 to close, so that the input power supply supplies power to the load again.

[0035] In summary, in the embodiment of the present application, a safety relay and at least two contactors are arranged between the input power supply and the load, and the emergency stop switch and the interlock device are connected in series in the reset circuit of the safety relay. When the emergency stop switch and the interlock device are both closed, the safety relay can output an enabling signal to the control coils of the two contactors through its output circuit by pressing the reset switch, controlling the two contactors to close, so that the input power supply supplies power to the load. When a fault occurs, any one of the emergency stop switch and the interlock device can be disconnected to disconnect the input circuit of the safety relay, and the output circuit of the safety relay stops outputting the enabling signal. At this time, the two contactors are disconnected, and the input power supply stops supplying power to the load. The present application realizes double power-off by using a safety relay and two contactors, avoids equipment damage caused by the failure of a single contact, and ensures reliable power-off of the equipment.

[0036] It should be noted that the embodiments described in the present application are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and illustrated in the drawings can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application.

[0037] The term "comprising" used in the description and claims should not be construed as limited to the content listed thereafter; it does not exclude other elements or steps. Therefore, it should be construed as specifying the presence of the mentioned features, wholes, steps or components, but does not exclude the presence or addition of one or more other features, wholes, steps or components and their groups. Therefore, the expression "equipment including device A and B" should not be limited to the equipment consisting only of components A and B.

[0038] The term "an embodiment" or "embodiment" mentioned in this specification means that the specific features, structures or characteristics described in combination with the embodiment are included in at least one embodiment of the present application. Therefore, the phrases "in an embodiment" or "in an embodiment" that appear throughout this specification do not necessarily all refer to the same embodiment, but may refer to the same embodiment. In addition, in the various embodiments of the present application, if there is no special explanation and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referred to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0039] Note that the above is only a preferred embodiment of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments only. Without departing from the concept of the present application, more other equivalent embodiments can be included, all of which fall within the protection scope of the present application.

Claims

1. A safety protection circuit for double power failure, arranged between the input power supply and the load, characterized in that: The circuit comprises a switching power supply, a safety relay, an emergency stop switch, an interlocking device, a reset switch and at least two contactors, the main contacts of the two contactors being connected in series between the input power supply and the load; The input power supply outputs a power signal to the switching power supply, and the switching power supply converts the power signal and outputs it to the power supply circuit and output circuit of the safety relay respectively. The safety relay includes at least two output circuits, and the input end of each output circuit is connected to the positive electrode of the switching power supply, and the output end is connected in series with a control coil of a contactor and then connected to the negative electrode of the switching power supply; The safety relay further comprises a reset circuit and an input circuit, the emergency stop switch and the interlocking device are connected in series in the input circuit, and the reset switch and the normally closed auxiliary contacts of the two contactors are connected in series in the reset circuit.

2. The circuit according to claim 1, characterized in that When the emergency stop switch and the interlocking device are closed, by pressing the reset switch, the two output circuits of the safety relay respectively output enable signals, and the two contactors are controlled to close, so that the input power supply supplies power to the load; When the emergency stop switch or the interlocking device is disconnected, the two output circuits of the safety relay stop outputting the enable signal, the two contactors are disconnected, and the input power supply stops supplying power to the load.

3. The circuit according to claim 1, characterized in that The safety relay comprises two input circuits, and the emergency stop switch and the interlocking device respectively adopt double contacts, and the double contacts of the emergency stop switch and the interlocking device are respectively connected in series in the two input circuits.

4. The circuit according to claim 1, characterized in that The output circuit of the safety relay includes at least one relay switch.

5. The circuit according to claim 1, characterized in that It also includes a leakage circuit breaker arranged at the output end of the input power supply.

6. The circuit according to claim 1, characterized in that It also includes a first circuit breaker arranged at the input end of the switching power supply.

7. The circuit according to claim 1, characterized in that It also includes a second circuit breaker arranged at the positive pole of the switching power supply.

8. The circuit according to claim 1, characterized in that The power signal output by the input power supply is an AC power signal of 200V-500V, and the switching power supply converts the AC power signal into a 24V DC voltage signal.

9. A power supply system, characterized in that: A safety protection circuit for double power off comprising the one described in any one of claims 1 to 8.

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