Relay driving circuit and relay device

Abstract

The utility model provides a relay driving circuit and a relay device. The relay driving circuit comprises a switching tube, a first resistor and a first capacitor. Wherein the first resistor and the first capacitor are connected in parallel to form an RC circuit, the RC circuit is connected in series in a coil loop circuit of the relay, a first end of the coil loop circuit is electrically connected with a power supply, a second end of the coil loop circuit is electrically connected with a first end of the switching tube, a second end of the switching tube is used for receiving a driving control signal, and a third end of the switching tube is grounded. When the driving control signal is a conduction signal, the switching tube conducts the electrical connection between the coil loop circuit and the ground, so that the conduction signal is not limited by a power supply, the universality of the relay driving circuit is improved, and when the coil is attracted, the voltage applied to the coil is equal to the power supply through the first capacitor, so that the coil can be attracted stably, and the service life of the relay driving circuit is prolonged. And after the relay coil is attracted, the coil is subjected to voltage division through the first resistor, so that the heating value and the loss of the coil are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of control devices, and in particular to a relay drive circuit and a relay device. Background Art

[0002] See also Figure 1 In actual application, the conduction signal A output by the controller is limited by the power supply received by the relay U1 coil (such as Figure 1 12V power supply in the device), and when the power supply drives the relay U1 to work, the coil of the relay U1 heats up, which increases the coil loss of the relay U1, which is not conducive to the thermal design and universality of the device. Utility Model Content

[0003] In view of the above, the present application provides a relay drive circuit and a relay device. The relay drive circuit has good universality and can reduce the loss of the relay coil.

[0004] A first aspect of the present application provides a relay drive circuit, comprising a switch, a first resistor, and a first capacitor. The first resistor and the first capacitor are connected in parallel to form an RC (Resistor-Capacitance) circuit, which is connected in series in a coil loop circuit of the relay. A first end of the coil loop circuit is electrically connected to a power supply, a second end of the coil loop circuit is electrically connected to a first end of the switch, the second end of the switch is configured to receive a drive control signal, and a third end of the switch is grounded.

[0005] When the driving control signal is a conduction signal, the switch tube can conduct the electrical connection between the coil loop circuit and the ground.

[0006] As an optional implementation manner, the first end, the second end and the third end of the switch tube are respectively the collector, the base and the emitter of the transistor.

[0007] As an optional implementation, the first end of the RC circuit is electrically connected to the power supply, the second end of the RC circuit is electrically connected to the first end of the coil of the relay, and the second end of the coil is electrically connected to the collector of the switching tube.

[0008] As an optional implementation, the first end of the RC circuit is electrically connected to the second end of the coil of the relay, the second end of the RC circuit is electrically connected to the collector of the switch tube, and the first end of the coil is electrically connected to the power supply.

[0009] As an optional implementation, the relay driving circuit further includes an absorption circuit connected in parallel with the coil of the relay.

[0010] As an optional implementation, the absorption circuit includes a first diode and a second diode. The cathode of the first diode is electrically connected to the cathode of the second diode, the anode of the first diode is electrically connected to the first end of the coil, and the anode of the second diode is electrically connected to the second end of the coil.

[0011] As an optional implementation, the first capacitor is an electrolytic capacitor, a positive electrode of the electrolytic capacitor is electrically connected to the power supply, and a negative electrode of the electrolytic capacitor is electrically connected to the coil of the relay.

[0012] As an optional implementation, the first resistor is an adjustable resistor.

[0013] As an optional implementation, the relay drive circuit further includes a second resistor, a third resistor, and a second capacitor. The first end of the second resistor is configured to receive a drive control signal, the second end of the second resistor is electrically connected to the second end of the switch tube, the third resistor is connected in parallel with the second capacitor, the first end of the third resistor and the first end of the second capacitor are electrically connected to a connection point between the second end of the second resistor and the second end of the switch tube, and the second end of the third resistor and the second end of the second capacitor are grounded.

[0014] A second aspect of the present application may also provide a relay device, comprising a controller, a relay, and a relay drive circuit as described in any one of the first aspects. The controller is electrically connected to the relay drive circuit, the controller is configured to output a drive control signal to the relay drive circuit, and the relay drive circuit is electrically connected to the relay. When the drive control signal is an on signal, the relay drive circuit controls the coil in the relay to engage; when the drive control signal is an off signal, the relay drive circuit controls the coil in the relay to disconnect.

[0015] The relay drive circuit and relay device of the present application can reduce relay coil losses and improve the universality of the relay. The relay drive circuit of the present application includes a switching transistor, a first resistor, and a first capacitor. The first resistor and the first capacitor are connected in parallel to form an RC circuit, which is connected in series in the coil loop circuit of the relay. The first end of the coil loop circuit is electrically connected to the power supply, the second end of the coil loop circuit is electrically connected to the first end of the switching transistor, the second end of the switching transistor is used to receive a drive control signal, and the third end of the coil loop circuit of the switching transistor is grounded. In actual application, when the drive control signal is an on signal, the switching transistor is used to conduct the electrical connection between the coil loop circuit and ground, so that the on signal is not limited by the power supply size, thereby improving the universality of the relay drive circuit. By connecting the RC circuit in series in the coil loop of the relay, when the coil is closed, the voltage applied to the coil can be equal to the power supply through the first capacitor in the RC circuit, and the current input to the coil can be limited by the first resistor, thereby ensuring that the coil can be stably closed. After the relay coil is stably closed, the first resistor divides the voltage of the coil to reduce the heat generation and loss of the relay coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a circuit diagram of a relay drive circuit in the prior art.

[0017] Figure 2 This is a first circuit diagram of a relay drive circuit provided in an embodiment of the present application.

[0018] Figure 3 This is a second circuit diagram of a relay drive circuit provided in an embodiment of the present application.

[0019] Figure 4 This is a third circuit diagram of a relay drive circuit provided in an embodiment of the present application.

[0020] Figure 5 This is a fourth circuit diagram of a relay drive circuit provided in an embodiment of the present application.

[0021] Figure 6 This is the fifth circuit diagram of a relay drive circuit provided in an embodiment of the present application.

[0022] Figure 7 This is a circuit diagram of a relay device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The technical solution of the present application is further described in detail below through the accompanying drawings and examples.

[0024] In the embodiments of this application, terms such as "first" and "second" are used solely to distinguish between different objects and should not be construed as indicating or implying relative importance or order. For example, terms such as "first application" and "second application" are used to distinguish between different applications, not to describe a specific order of applications. Features defined as "first" or "second" may explicitly or implicitly include one or more of these features.

[0025] An embodiment of the present application provides a relay drive circuit 10. Figure 2 , is a first circuit diagram provided in an embodiment of the present application, including a switch tube Q1, a first resistor R1 and a first capacitor EC1.

[0026] Among them, the first resistor R1 and the first capacitor EC1 are connected in parallel to form an RC circuit 01, and the RC circuit 01 is connected in series in the coil loop circuit of the relay K1. The first end of the coil loop circuit is electrically connected to the power supply U1, and the second end of the coil loop circuit is electrically connected to the first end of the switch tube Q1. The second end of the switch tube Q1 is used to receive the drive control signal V_PWM, and the third end of the switch tube Q1 is grounded.

[0027] In practical applications, such as Figure 2 As shown, the switch tube Q1 can be an NPN transistor, and the first end of the switch tube Q1 corresponds to the collector of the transistor, the second end of the switch tube Q1 corresponds to the base of the transistor, and the third end of the switch tube Q1 corresponds to the emitter of the transistor; optionally, refer to Figure 2 The first capacitor EC1 can be an electrolytic capacitor, wherein the positive electrode of the electrolytic capacitor is electrically connected to the power supply U1, and the negative electrode of the electrolytic capacitor is electrically connected to the coil of the relay K1. The capacitance of the electrolytic capacitor is not specifically limited here and depends on its actual application environment, which is within the protection scope of this application.

[0028] The working process of the above-mentioned relay driving circuit 10 is as follows: when the driving control signal V_PWM is a conduction signal, the switch tube Q1 conducts the electrical connection between the coil loop circuit and the ground. At this time, the voltage across the first capacitor EC1 will not change suddenly, and the first capacitor EC1 can be regarded as a short-circuit state, so that the voltage applied to the two ends of the relay coil is equal to the power supply U1, and the current input to the relay coil is limited by the first resistor R1 to drive the relay coil to stably attract; after the relay coil is attracted, the power supply U1 charges the first capacitor EC1. After the first capacitor EC1 is charged, the two ends of the first capacitor EC1 can be regarded as an open circuit, and the first resistor R1 divides the power supply U1 to reduce the voltage across the relay coil and make the voltage across the coil within a preset driving voltage range; when the driving control signal V_PWM is an off signal, the switch tube Q1 disconnects the electrical connection between the coil loop circuit and the ground to control the relay coil to be disconnected.

[0029] In actual applications, the voltage value of the conduction signal received by the second end of the switch tube Q1 needs to be greater than the voltage value of the third end of the switch tube Q1. In this application, the third end of the switch tube Q1 is grounded to reduce the limitation of the conduction signal, thereby improving the universality of the relay drive circuit 10. In actual applications, the voltage value of the conduction signal is greater than 0.7V to drive the switch tube Q1 to turn on. There is no specific limitation on the voltage value of the conduction signal here, which can be determined according to the actual application environment and is within the protection scope of this application.

[0030] The relay drive circuit 10 provided in this embodiment includes a switch Q1, a first resistor R1, and a first capacitor EC1. The first resistor R1 and the first capacitor EC1 are connected in parallel to form an RC circuit O1. The RC circuit O1 is connected in series to a coil loop circuit of the relay K1. A first end of the coil loop circuit is electrically connected to a power source U1, a second end of the coil loop circuit is electrically connected to a first end of the switch Q1, a second end of the switch Q1 is configured to receive a drive control signal V_PWM, and a third end of the coil loop circuit of the switch Q1 is grounded. In actual applications, when the drive control signal V_PWM is a conduction signal, the switch tube Q1 is used to conduct the electrical connection between the coil loop circuit and the ground, so that the conduction signal is not limited by the size of the power supply U1, thereby improving the universality of the relay drive circuit 10. In addition, by connecting the RC circuit 01 in series in the coil loop, when the coil is attracted, the voltage applied to the coil can be equal to the power supply U1 through the first capacitor EC1 in the RC circuit 01, and the current input to the coil is limited by the first resistor R1, so that the coil can be stably attracted. After the relay coil is stably attracted, the coil is divided by the first resistor R1 to reduce the heat generation and loss of the relay coil.

[0031] On the basis of the above embodiment, the relay drive circuit 10 provided in this application can be as follows Figure 2 As shown, a first end of the RC circuit 01 is electrically connected to the power supply U1 , a second end of the RC circuit 01 is electrically connected to a first end of the coil of the relay K1 , and a second end of the coil is electrically connected to the collector of the switch tube Q1 .

[0032] Optional, Figure 3 This is the second circuit diagram of the relay drive circuit 10 provided in the present application, wherein the first end of the RC circuit 01 is electrically connected to the second end of the coil of the relay K1, the second end of the RC circuit 01 is electrically connected to the collector of the switch tube Q1, and the first end of the coil is electrically connected to the power supply U1.

[0033] In practical applications, the first resistor R1 can optionally be an adjustable resistor. The resistance of the first resistor R1 can be determined based on the pull-in voltage of the coil of the relay K1 to ensure stable pull-in of the coil of the relay K1 and reduce coil heat generation and losses. Therefore, the resistance value of the first resistor R1 is not specifically limited here and can be determined based on the actual application environment and is within the scope of protection of this application.

[0034] The relay drive circuit 10 provided in this embodiment connects an RC circuit 01 in series in the coil loop of the relay K1. When the coil is energized, the voltage applied to the coil is equal to the power supply U1 through the first capacitor EC1 in the RC circuit 01, thereby enabling the coil to be stably energized. After the relay coil is stably energized, the coil voltage is divided by the first resistor R1 to reduce heat generation and loss in the relay coil.

[0035] On the basis of the above embodiment, another embodiment of the present application further provides a relay driving circuit 10, see Figure 4 (exist Figure 2 ) is a third circuit diagram provided in an embodiment of the present application, wherein the relay drive circuit 10 further includes an absorption circuit 02. The absorption circuit 02 is connected in parallel with the coil of the relay K1.

[0036] Optional, see Figure 5 In the fourth circuit diagram provided in the embodiment of the present application, the absorption circuit 02 includes a first diode D1 and a second diode ZD1. The cathode of the first diode D1 is electrically connected to the cathode of the second diode ZD1, the anode of the first diode D1 is electrically connected to the first end of the coil, and the anode of the second diode ZD1 is electrically connected to the second end of the coil.

[0037] In practical applications, the first diode D1 is used to absorb spike voltages in the coil circuit to prevent them from affecting the coil's engagement and disconnection. In practical applications, a voltage regulator diode can be used as the second diode ZD1 to stabilize the voltage across the coil to prevent voltage fluctuations from affecting the coil's engagement. Practical applications are not limited to these and will vary depending on the specific application environment, all of which are within the scope of protection of this application.

[0038] The absorption circuit 02 in the relay drive circuit 10 provided in this embodiment adopts the first diode D1 to absorb the peak voltage in the coil loop to prevent the peak voltage from affecting the attraction and disconnection of the coil, thereby improving the reliability of the relay K1. The second diode ZD1 is used to stabilize the voltage across the coil to prevent voltage fluctuations from affecting the attraction of the coil, thereby further improving the reliability of the relay K1.

[0039] On the basis of the above embodiment, another embodiment of the present application further provides a relay driving circuit 10, see Figure 6 (exist Figure 5 ) is a fifth circuit diagram provided in an embodiment of the present application, wherein the relay drive circuit 10 further includes a second resistor R3, a third resistor R2 and a second capacitor C1.

[0040] Among them, the first end of the second resistor R3 is used to receive the drive control signal V_PWM, the second end of the second resistor R3 is electrically connected to the second end of the switch tube Q1, the third resistor R2 is connected in parallel with the second capacitor C1, the first end of the third resistor R2 and the first end of the second capacitor C1 are electrically connected to the connection point between the second end of the second resistor R3 and the second end of the switch tube Q1, and the second end of the third resistor R2 and the second end of the second capacitor C1 are grounded.

[0041] In practical applications, the second resistor R3 is used to limit the current input to the second terminal of the switch Q1. The third resistor R2 is used to pull down the second terminal of the switch Q1 when the drive control signal V_PWM is the off signal, preventing the switch Q1 from floating and falsely triggering. The second capacitor C1 can be a ceramic capacitor to stabilize the voltage of the on-signal. Practical applications are not limited to these and can be determined based on the specific application environment, all of which are within the scope of protection of this application.

[0042] The relay drive circuit 10 provided in this embodiment uses a second resistor R3 to limit the current input to the second terminal of the switch Q1 to prevent excessive current from the on-state signal from damaging the switch Q1, thereby improving the reliability of the relay drive circuit 10. Furthermore, a second capacitor C1 is used to stabilize the voltage of the drive control signal V_PWM to prevent voltage fluctuations of the on-state signal from affecting the turn-off of the switch Q1. Furthermore, a third resistor R2 is used to pull down the second terminal of the switch Q1 to prevent false triggering of the switch Q1 due to floating, further improving the reliability of the relay drive circuit 10.

[0043] Based on the above examples, please refer to Figure 7 Another embodiment of the present application further provides a relay device, including a controller 20, a relay K1, and the relay drive circuit 10 as described in any of the above embodiments.

[0044] The controller 20 is electrically connected to the relay drive circuit 10 . The controller 20 is used to output a drive control signal V_PWM to the relay drive circuit 10 . The relay drive circuit 10 is used to electrically connect to the relay K1 .

[0045] Specifically, when the drive control signal V_PWM is an on signal, the relay drive circuit can control the coil in the relay K1 to be attracted, and when the drive control signal V_PWM is an off signal, the relay drive circuit can control the coil in the relay K1 to be disconnected.

[0046] In practical applications, a low-voltage chip such as an MCU (Micro Controller Unit) or a DSP (Digital Signal Processor) can be used as the controller 20 to output the corresponding drive control signal V_PWM to the relay drive circuit 10, thereby controlling the relay K1 through the relay drive circuit 10. Furthermore, the relay device provided in this embodiment can be applied to hardware circuit designs that require a relay device to implement an isolating switch function. For example, in a vehicle body that requires a relay device to implement an isolating switch function, the actual application is not limited to this and depends on the specific application environment, all of which are within the scope of protection of this application.

[0047] The relay device provided in this embodiment adopts the relay drive circuit 10 as described in any of the above embodiments, so that the conduction signal output by the controller 20 is not limited by the size of the power supply U1 received by the relay coil, thereby improving the universality of the relay drive circuit 10, realizing the low power consumption design of the relay K1, reducing the heat generation and loss of the relay coil, and reducing the manufacturing cost of the relay drive circuit 10.

[0048] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments and that the present application can be implemented in other specific forms without departing from the spirit or essential features of the present application. Therefore, as long as they are within the scope of the essence of the present application, appropriate changes and modifications made to the above embodiments should fall within the scope of protection claimed in the present application.

Claims

1. A relay drive circuit, characterized in that: include: A switch tube, a first resistor and a first capacitor; wherein, The first resistor and the first capacitor are connected in parallel to form an RC circuit, and the RC circuit is connected in series in a coil loop circuit of the relay. A first end of the coil loop circuit is electrically connected to a power supply, a second end of the coil loop circuit is electrically connected to a first end of the switch tube, a second end of the switch tube is used to receive a drive control signal, and a third end of the switch tube is grounded. When the driving control signal is a conduction signal, the switch tube can conduct the electrical connection between the coil loop circuit and the ground.

2. The relay drive circuit according to claim 1, wherein: The first end, the second end and the third end of the switch tube are respectively the collector, the base and the emitter of the triode.

3. The relay drive circuit according to claim 2, wherein: A first end of the RC circuit is electrically connected to the power supply, a second end of the RC circuit is electrically connected to a first end of the coil of the relay, and a second end of the coil is electrically connected to the collector of the switching tube.

4. The relay drive circuit according to claim 2, wherein: The first end of the RC circuit is electrically connected to the second end of the coil of the relay, the second end of the RC circuit is electrically connected to the collector of the switching tube, and the first end of the coil is electrically connected to the power supply.

5. The relay driving circuit according to claim 1, wherein: The relay drive circuit further includes: an absorption circuit; The absorption circuit is connected in parallel with the coil of the relay.

6. The relay driving circuit according to claim 5, characterized in that: The absorption circuit includes: a first diode and a second diode; The cathode of the first diode is electrically connected to the cathode of the second diode, the anode of the first diode is electrically connected to the first end of the coil, and the anode of the second diode is electrically connected to the second end of the coil.

7. The relay driving circuit according to claim 1, wherein: The first capacitor is an electrolytic capacitor; The positive electrode of the electrolytic capacitor is electrically connected to the power supply, and the negative electrode of the electrolytic capacitor is electrically connected to the coil of the relay.

8. The relay driving circuit according to claim 1, wherein: The first resistor is an adjustable resistor.

9. The relay drive circuit according to any one of claims 1 to 8, characterized in that: The relay drive circuit further includes: a second resistor, a third resistor and a second capacitor; The first end of the second resistor is used to receive the drive control signal, the second end of the second resistor is electrically connected to the second end of the switch tube, the third resistor is connected in parallel with the second capacitor, the first end of the third resistor and the first end of the second capacitor are electrically connected to the connection point between the second end of the second resistor and the second end of the switch tube, and the second end of the third resistor and the second end of the second capacitor are grounded.

10. A relay device, characterized in that: The relay includes a controller, a relay, and a relay driving circuit according to any one of claims 1 to 9; wherein, The controller is electrically connected to the relay drive circuit, the controller is used to output a drive control signal to the relay drive circuit, and the relay drive circuit is electrically connected to the relay; When the driving control signal is an on signal, the relay driving circuit can control the coil in the relay to be attracted; When the driving control signal is an off signal, the relay driving circuit can control the coil in the relay to be disconnected.

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