Control circuit for quick closing of relay and implementation method of control circuit

Abstract

The invention discloses a control circuit for quick closing of a relay and an implementation method thereof, and relates to the technical field of relay control circuits, the control circuit comprises a relay S1, a diode D1, voltage stabilizing diodes D2 and D3, triodes Q1 and Q2, an energy storage capacitor C1, and resistors R1, R2, R3, R4 and R5, a point 3 and a point 4 of the S1 are connected to two ends of a load; a point 1 of the S1 is simultaneously connected with a negative electrode of the D1 and a positive electrode of the C1, the positive electrode of the D1 is connected with a 12V power supply, a negative electrode of the C1 is grounded through the R1 and is simultaneously connected with a collector electrode of the Q1, and a base electrode of the Q1 and an emitter electrode are jointly connected with the 12V power supply through the R2 and the R3 which are connected in series; a point 2 of the S1 is grounded through D3 and is connected with a collector electrode of Q2, a base electrode of the Q2 is connected with a trigger signal through R4, and an emitter electrode of the Q2 is grounded; the collector electrode of Q2 is also connected with the cathode of D2, and the anode of D2 is connected with a 12V power supply through R5 and R3 which are connected in series. By changing the trigger signal, the working voltage of the coil can be increased at the moment that the relay is connected, and the coil recovers to the normal working voltage after the contact is closed.

Description

Technical Field

[0001] The invention relates to the technical field of relay control circuits, in particular to a relay fast closing control circuit and an implementation method thereof. Background Art

[0002] In conventional relay control circuits, a transistor is generally used to control whether the relay coil is energized, and then to control whether the relay contacts are connected, thereby achieving control of the load power supply circuit. Generally, the rated operating voltage of the relay is given in the data sheet, and the relay will be at this rated voltage, but in some industrial applications, the relay contacts need to be able to close quickly. To shorten the working time of the relay, the conventional method is to increase the working voltage of the relay coil, but this method will increase the power consumption of the coil, and the increased power consumption will cause the coil to heat up, affecting the service life of the relay. Summary of the invention

[0003] Aiming at the problem of high power consumption and short service life in conventional methods of accelerating relay conduction, the present invention provides a control circuit for rapid relay closure and an implementation method thereof, so as to increase the coil working voltage at the moment when the relay is turned on, and restore the coil to the normal working voltage after the contacts are closed.

[0004] In the first aspect, the present invention provides a control circuit for fast closing of a relay, and the technical solution adopted to solve the above technical problems is as follows:

[0005] A control circuit for fast closing of a relay comprises a relay S1, a diode D1, voltage-stabilizing diodes D2 and D3, transistors Q1 and Q2, an energy storage capacitor C1, resistors R1, R2, R3, R4 and R5, wherein:

[0006] The common point 3 and the normally closed contact 4 of the relay S1 are connected to both ends of the load RL;

[0007] The normally closed contact 1 of the relay S1 is connected to the cathode of the diode D1 and the anode of the energy storage capacitor C1 at the same time. The anode of the diode D1 is connected to the 12V power supply. The cathode of the energy storage capacitor C1 is grounded through the resistor R1 and connected to the collector 3 of the transistor Q1. The base 1 of the transistor Q1 is connected to the 12V power supply together with the emitter 2 through the series-connected resistors R2 and R3.

[0008] The normally open contact 2 of the relay S1 is grounded through the voltage-stabilizing diode D3, and is connected to the collector 3 of the transistor Q2. The base 1 of the transistor Q2 is connected to the trigger signal through the resistor R4, and the emitter 2 of the transistor Q2 is grounded; the collector 3 of the transistor Q2 is also connected to the cathode of the voltage-stabilizing diode D2, and the anode of the voltage-stabilizing diode D2 is connected to the 12V power supply through the series-connected resistors R5 and R3.

[0009] Optionally, the trigger signal involved is a high level signal or a low level signal;

[0010] When the trigger signal is at a low level, the relay S1 does not act, and the 12V power supply charges the energy storage capacitor C1 through the diode D1, or the normally open contact 2 of the relay S1 changes from a closed state to an open state;

[0011] When the trigger signal is at a high level, the energy storage capacitor C1 discharges and the normally open contact 2 of the relay S1 closes quickly.

[0012] Further optionally, when the trigger signal involved is at a low level, the transistor Q2 is not conducting, the transistor Q1 is not conducting, the voltage across the coil of the relay S1 is 0, the relay S1 does not operate, and the 12V power supply charges the energy storage capacitor C1 through the diode D1;

[0013] When the energy storage capacitor C1 is fully charged to 12V, the trigger signal becomes high level. At this time, transistor Q2 is turned on, transistor Q1 is turned on, and the negative electrode of the energy storage capacitor C1 is quickly raised to 12V, which makes the voltage of the positive electrode of the energy storage capacitor C1 relative to the reference ground reach 24V. The normally open contact 2 of the relay S1 is closed, and the energy storage capacitor C1 begins to discharge through R1 and the relay coil, and the 24V voltage gradually decreases;

[0014] When the voltage of the energy storage capacitor C1 drops to the rated conduction voltage of 12V, the trigger signal becomes low again, the transistor Q2 is not turned on, and the reverse electromotive force generated by the coil of relay S1 continues to flow through the coil, the voltage-stabilizing diode D2, the resistor R5, the resistor R3 and the 12V power supply circuit. The voltage across the coil of relay S1 drops to 0V, the normally open contact 2 of relay S1 opens, and the load RL is de-energized.

[0015] Preferably, R1 is a current limiting resistor, R2 and R4 are base resistors, R3 is a pull-up resistor, and R5 is a pull-down resistor.

[0016] Preferably, the load RL involved is a hypothetical load, and when the normally open contact 2 of the relay S1 is closed, the load RL works normally, and when the normally open contact 2 of the relay S1 is opened, the load RL is de-energized.

[0017] In a second aspect, the present invention provides a method for implementing a control circuit for rapid closure of a relay, and the technical solution adopted to solve the above technical problem is as follows:

[0018] A control circuit implementation method for fast closing of a relay, the control circuit comprising a relay S1, a diode D1, voltage-stabilizing diodes D2 and D3, transistors Q1 and Q2, an energy storage capacitor C1, resistors R1, R2, R3, R4 and R5, wherein: a common point 3 and a normally closed contact 4 of the relay S1 are connected to two ends of a load RL; the normally closed contact 1 of the relay S1 is simultaneously connected to the cathode of the diode D1 and the anode of the energy storage capacitor C1, the anode of the diode D1 is connected to a 12V power supply, the cathode of the energy storage capacitor C1 is grounded through the resistor R1, and the anode of the diode D1 is connected to a 12V power supply. The collector 3 of the transistor Q1 is connected, and the base 1 of the transistor Q1 is connected to the 12V power supply together with the emitter 2 through the series resistors R2 and R3; the normally open contact 2 of the relay S1 is grounded through the voltage-stabilizing diode D3, and the collector 3 of the transistor Q2 is connected at the same time, the base 1 of the transistor Q2 is connected to the trigger signal through the resistor R4, and the emitter 2 of the transistor Q2 is grounded; the collector 3 of the transistor Q2 is also connected to the cathode of the voltage-stabilizing diode D2, and the anode of the voltage-stabilizing diode D2 is connected to the 12V power supply through the series resistors R5 and R3;

[0019] The control circuit is implemented as follows: when the trigger signal adopts a low level, the relay S1 does not work, and the 12V power supply charges the energy storage capacitor C1 through the diode D1; when the trigger signal adopts a high level, the energy storage capacitor C1 discharges, thereby realizing the rapid closing of the normally open contact 2 of the relay S1.

[0020] Optionally, when the trigger signal is at a low level, transistor Q2 is not conducting, transistor Q1 is not conducting, the voltage across the coil of relay S1 is 0, relay S1 does not operate, and the 12V power supply charges the energy storage capacitor C1 through diode D1;

[0021] When the energy storage capacitor C1 is fully charged to 12V, the trigger signal becomes high level. At this time, transistor Q2 is turned on, transistor Q1 is turned on, and the negative electrode of the energy storage capacitor C1 is quickly raised to 12V, which makes the voltage of the positive electrode of the energy storage capacitor C1 relative to the reference ground reach 24V. The normally open contact 2 of the relay S1 is closed, and the energy storage capacitor C1 begins to discharge through R1 and the relay coil, and the 24V voltage gradually decreases;

[0022] When the voltage of the energy storage capacitor C1 drops to the rated conduction voltage of 12V, the trigger signal becomes low again, the transistor Q2 is not turned on, and the reverse electromotive force generated by the coil of relay S1 continues to flow through the coil, the voltage-stabilizing diode D2, the resistor R5, the resistor R3 and the 12V power supply circuit. The voltage across the coil of relay S1 drops to 0V, the normally open contact 2 of relay S1 opens, and the load RL is de-energized.

[0023] Preferably, R1 is a current limiting resistor, R2 and R4 are base resistors, R3 is a pull-up resistor, and R5 is a pull-down resistor.

[0024] Preferably, the load RL involved is a hypothetical load, and when the normally open contact 2 of the relay S1 is closed, the load RL works normally, and when the normally open contact 2 of the relay S1 is opened, the load RL is de-energized.

[0025] A control circuit for rapid closing of a relay and an implementation method thereof of the present invention have the following beneficial effects compared with the prior art:

[0026] The present invention can increase the coil working voltage at the moment the relay is turned on, and the coil returns to the normal working voltage after the contacts are closed, which has the advantages of shortening the action time of the relay and ensuring the service life of the relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Attached Figure 1 It is a control circuit diagram of embodiment 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the technical solution, the technical problem solved and the technical effect of the present invention more clearly understood, the technical solution of the present invention is clearly and completely described below in conjunction with specific embodiments.

[0029] Embodiment 1:

[0030] Combined with Figure 1 This embodiment provides a control circuit for fast closing of a relay, which includes a relay S1, a diode D1, voltage-stabilizing diodes D2 and D3, transistors Q1 and Q2, an energy storage capacitor C1, resistors R1, R2, R3, R4 and R5, wherein:

[0031] The common point 3 and the normally closed contact 4 of the relay S1 are connected to both ends of the load RL;

[0032] The normally closed contact 1 of the relay S1 is connected to the cathode of the diode D1 and the anode of the energy storage capacitor C1 at the same time. The anode of the diode D1 is connected to the 12V power supply. The cathode of the energy storage capacitor C1 is grounded through the resistor R1 and connected to the collector 3 of the transistor Q1. The base 1 of the transistor Q1 is connected to the 12V power supply together with the emitter 2 through the series-connected resistors R2 and R3.

[0033] The normally open contact 2 of the relay S1 is grounded through the voltage-stabilizing diode D3, and is connected to the collector 3 of the transistor Q2. The base 1 of the transistor Q2 is connected to the trigger signal through the resistor R4, and the emitter 2 of the transistor Q2 is grounded; the collector 3 of the transistor Q2 is also connected to the cathode of the voltage-stabilizing diode D2, and the anode of the voltage-stabilizing diode D2 is connected to the 12V power supply through the series-connected resistors R5 and R3.

[0034] In this embodiment, ① the role of the diode D1 is to prevent the 12V power supply from being discharged when the positive electrode voltage of the energy storage capacitor C1 is higher than 12V; ② the role of the voltage stabilizing diode D2 is to protect the transistor Q1. When the relay S1 is disconnected, a very high reverse electromotive force will be generated at both ends of its coil. This electromotive force may far exceed the maximum voltage limit that the transistor Q1 can withstand, resulting in device damage. In order to prevent this from happening, the voltage stabilizing diode D2 is added. When the reverse electromotive force is generated, the voltage stabilizing diode D2 starts to work in its reverse breakdown region, thereby limiting the voltage increase and protecting the transistor Q1 from high-voltage shock; ③ the role of the voltage stabilizing diode D3 is to protect the transistor Q2 and prevent the reverse electromotive force from breaking through the collector 3 of the transistor Q2; ④ the transistors Q1 and Q2 act as switches and charge the energy storage capacitor C1 when they are turned on at the same time; ⑤ the energy storage capacitor C1 acts as an energy storage boost to change the voltage of the positive electrode of the coil; ⑥ the relay S1, i.e. the controlled object, will generate magnetism when a certain DC voltage is given to its coil, causing the contacts to close, and the contacts will not close when there is no magnetism.

[0035] In this embodiment, point 1 of relay S1 is a normally closed contact. When the relay is not powered on, contact 1 and contact 4 are in a closed state, and current can pass through. This is usually used to maintain the circuit in the default working state when the relay is not energized. Point 2 of relay S1 is a normally open contact. After the relay is powered on and energized, contact 2 and contact 3 will be closed, thereby allowing current to pass through. This is usually used to start or connect a circuit after the relay is energized. Point 3 of relay S1 is called a common point or control terminal. This point is connected to the coil of relay S1. When the coil is energized, it will drive relay S1. The switching action causes the normally closed contact to open and the normally open contact to close; point 4 of relay S1 is also a normally closed contact, paired with point 1. When the relay is not energized, contact 1 and contact 4 are closed and used to connect the circuit; in summary, point 1 and point 4 are contacts that are closed when relay S1 is not energized, and are usually used to maintain the default state of the circuit; point 2 and point 3 are contacts that are closed after relay S1 is energized, and are used to change the circuit state after the relay is activated; point 3, as the control end, is connected to the coil of relay S1 and is the key part of controlling the action of relay S1.

[0036] In this embodiment, R1 is a current limiting resistor, R2 and R4 are base resistors, R3 is a pull-up resistor, and R5 is a pull-down resistor; the load RL is an assumed load, when the normally open contact 2 of the relay S1 is closed, the load RL works normally, and when the normally open contact 2 of the relay S1 is opened, the load RL is de-energized.

[0037] Based on the control circuit of this embodiment, the rapid closing of the relay is achieved by changing the trigger signal: when the trigger signal adopts a low level, the relay S1 does not work, and the 12V power supply charges the energy storage capacitor C1 through the diode D1; when the trigger signal adopts a high level, the energy storage capacitor C1 discharges, thereby achieving the rapid closing of the normally open contact 2 of the relay S1.

[0038] Specifically, when the trigger signal is at a low level, transistor Q2 is not conducting, transistor Q1 is not conducting, the voltage across the coil of relay S1 is 0, relay S1 does not operate, and the 12V power supply charges the energy storage capacitor C1 through diode D1;

[0039] When the energy storage capacitor C1 is fully charged to 12V, the trigger signal becomes high level. At this time, transistor Q2 is turned on, transistor Q1 is turned on, and the negative electrode of the energy storage capacitor C1 is quickly raised to 12V, which makes the voltage of the positive electrode of the energy storage capacitor C1 relative to the reference ground reach 24V. The normally open contact 2 of the relay S1 is closed, and the energy storage capacitor C1 begins to discharge through R1 and the relay coil, and the 24V voltage gradually decreases;

[0040] When the voltage of the energy storage capacitor C1 drops to the rated conduction voltage of 12V, the trigger signal becomes low again, the transistor Q2 is not turned on, and the reverse electromotive force generated by the coil of relay S1 continues to flow through the coil, the voltage-stabilizing diode D2, the resistor R5, the resistor R3 and the 12V power supply circuit. The voltage across the coil of relay S1 drops to 0V, the normally open contact 2 of relay S1 opens, and the load RL is de-energized.

[0041] In summary, by using a control circuit for rapid closure of a relay and an implementation method thereof of the present invention, the operating voltage of the coil can be increased at the moment the relay is turned on, and the coil returns to the normal operating voltage after the contacts are closed, which has the advantages of shortening the action time of the relay while ensuring the service life of the relay.

[0042] The above specific examples are used to explain the principles and implementation methods of the present invention in detail. These examples are only used to help understand the core technical content of the present invention. Based on the above specific embodiments of the present invention, any improvements and modifications made by technicians in this technical field without departing from the principles of the present invention should fall within the scope of patent protection of the present invention.

Claims

1. A control circuit for fast closing of a relay, characterized in that: It includes relay S1, diode D1, voltage zener diodes D2 and D3, transistors Q1 and Q2, energy storage capacitor C1, resistors R1, R2, R3, R4 and R5, where: The common point 3 and the normally closed contact 4 of the relay S1 are connected to both ends of the load RL; The normally closed contact 1 of the relay S1 is connected to the cathode of the diode D1 and the anode of the energy storage capacitor C1 at the same time. The anode of the diode D1 is connected to the 12V power supply. The cathode of the energy storage capacitor C1 is grounded through the resistor R1 and connected to the collector 3 of the transistor Q1. The base 1 of the transistor Q1 is connected to the 12V power supply together with the emitter 2 through the series-connected resistors R2 and R3. The normally open contact 2 of the relay S1 is grounded through the voltage-stabilizing diode D3, and is connected to the collector 3 of the transistor Q2. The base 1 of the transistor Q2 is connected to the trigger signal through the resistor R4, and the emitter 2 of the transistor Q2 is grounded; the collector 3 of the transistor Q2 is also connected to the cathode of the voltage-stabilizing diode D2, and the anode of the voltage-stabilizing diode D2 is connected to the 12V power supply through the series-connected resistors R5 and R3.

2. A relay fast closing control circuit according to claim 1, characterized in that: The trigger signal is a high level signal or a low level signal; When the trigger signal is at a low level, the relay S1 does not act, and the 12V power supply charges the energy storage capacitor C1 through the diode D1, or the normally open contact 2 of the relay S1 changes from a closed state to an open state; When the trigger signal is at a high level, the energy storage capacitor C1 discharges and the normally open contact 2 of the relay S1 closes quickly.

3. A relay fast closing control circuit according to claim 2, characterized in that: When the trigger signal is at a low level, transistor Q2 is not conducting, transistor Q1 is not conducting, the voltage across the coil of relay S1 is 0, relay S1 does not operate, and the 12V power supply charges the energy storage capacitor C1 through diode D1; When the energy storage capacitor C1 is fully charged to 12V, the trigger signal becomes high level. At this time, transistor Q2 is turned on, transistor Q1 is turned on, and the negative electrode of the energy storage capacitor C1 is quickly raised to 12V, which makes the voltage of the positive electrode of the energy storage capacitor C1 relative to the reference ground reach 24V. The normally open contact 2 of the relay S1 is closed, and the energy storage capacitor C1 begins to discharge through R1 and the relay coil, and the 24V voltage gradually decreases; When the voltage of the energy storage capacitor C1 drops to the rated conduction voltage of 12V, the trigger signal becomes low again, the transistor Q2 is not turned on, and the reverse electromotive force generated by the coil of relay S1 continues to flow through the coil, the voltage-stabilizing diode D2, the resistor R5, the resistor R3 and the 12V power supply circuit. The voltage across the coil of relay S1 drops to 0V, the normally open contact 2 of relay S1 opens, and the load RL is de-energized.

4. A relay fast closing control circuit according to claim 1, characterized in that: The R1 is a current limiting resistor, the R2 and R4 are base resistors, the R3 is a pull-up resistor, and the R5 is a pull-down resistor.

5. A relay fast closing control circuit according to claim 1, characterized in that: The load RL is an assumed load. When the normally open contact 2 of the relay S1 is closed, the load RL works normally. When the normally open contact 2 of the relay S1 is opened, the load RL is de-energized.

6. A method for realizing a control circuit for rapid closing of a relay, characterized in that: The control circuit comprises a relay S1, a diode D1, voltage-stabilizing diodes D2 and D3, transistors Q1 and Q2, an energy storage capacitor C1, resistors R1, R2, R3, R4 and R5, wherein: a common point 3 and a normally closed contact 4 of the relay S1 are connected to both ends of a load RL; the normally closed contact 1 of the relay S1 is simultaneously connected to the cathode of the diode D1 and the anode of the energy storage capacitor C1, the anode of the diode D1 is connected to a 12V power supply, the cathode of the energy storage capacitor C1 is grounded through the resistor R1, and is simultaneously connected to the cathode of the transistor Q1. The collector 3, the base 1 of the transistor Q1 and the emitter 2 are connected to the 12V power supply through the series resistors R2 and R3; the normally open contact 2 of the relay S1 is grounded through the voltage-stabilizing diode D3, and is connected to the collector 3 of the transistor Q2 at the same time. The base 1 of the transistor Q2 is connected to the trigger signal through the resistor R4, and the emitter 2 of the transistor Q2 is grounded; the collector 3 of the transistor Q2 is also connected to the cathode of the voltage-stabilizing diode D2, and the anode of the voltage-stabilizing diode D2 is connected to the 12V power supply through the series resistors R5 and R3; The control circuit is implemented as follows: when the trigger signal adopts a low level, the relay S1 does not work, and the 12V power supply charges the energy storage capacitor C1 through the diode D1; when the trigger signal adopts a high level, the energy storage capacitor C1 discharges, thereby realizing the rapid closing of the normally open contact 2 of the relay S1.

7. A method for realizing a control circuit for rapid closing of a relay according to claim 6, characterized in that: When the trigger signal is at a low level, transistor Q2 is not conducting, transistor Q1 is not conducting, the voltage across the coil of relay S1 is 0, relay S1 does not operate, and the 12V power supply charges the energy storage capacitor C1 through diode D1; When the energy storage capacitor C1 is fully charged to 12V, the trigger signal becomes high level. At this time, transistor Q2 is turned on, transistor Q1 is turned on, and the negative electrode of the energy storage capacitor C1 is quickly raised to 12V, which makes the voltage of the positive electrode of the energy storage capacitor C1 relative to the reference ground reach 24V. The normally open contact 2 of the relay S1 is closed, and the energy storage capacitor C1 begins to discharge through R1 and the relay coil, and the 24V voltage gradually decreases; When the voltage of the energy storage capacitor C1 drops to the rated conduction voltage of 12V, the trigger signal becomes low again, the transistor Q2 is not turned on, and the reverse electromotive force generated by the coil of relay S1 continues to flow through the coil, the voltage-stabilizing diode D2, the resistor R5, the resistor R3 and the 12V power supply circuit. The voltage across the coil of relay S1 drops to 0V, the normally open contact 2 of relay S1 opens, and the load RL is de-energized.

8. The method for realizing a control circuit for rapid closing of a relay according to claim 6, characterized in that: The R1 is a current limiting resistor, the R2 and R4 are base resistors, the R3 is a pull-up resistor, and the R5 is a pull-down resistor.

9. The method for realizing a control circuit for rapid closing of a relay according to claim 6, characterized in that: The load RL is an assumed load. When the normally open contact 2 of the relay S1 is closed, the load RL works normally. When the normally open contact 2 of the relay S1 is opened, the load RL is de-energized.

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