Double-coil contactor

Abstract

The utility model discloses a double-coil contactor, and the contactor comprises a power module which is used for accessing an external power supply voltage to generate a DC voltage, so as to enable a coil loop to be electrically conducted, and carrying out the voltage reduction of the DC voltage, and obtaining a power supply voltage; the external power supply is an AC power supply or a DC power supply; the sampling comparison module is used for sampling the direct-current voltage and generating a working voltage according to the power supply voltage when the sampling voltage is greater than a preset voltage threshold value; the driving module is used for controlling the pull-in coil loop to be electrically conducted based on the direct current voltage in response to the power supply voltage and the working voltage, and controlling the pull-in coil loop to be electrically disconnected in response to the trigger signal; the time delay module is used for generating a trigger signal when the duration of electrical conduction of the pull-in coil loop reaches a preset duration. According to the double-coil contactor, the AC voltage of the AC power supply can be converted into the DC voltage for control through the power supply module, and the application range of the double-coil contactor is greatly expanded.

Description

Technical Field

[0001] The present application relates to the field of industrial control technology, and in particular to a dual-coil contactor. Background Art

[0002] There are generally two implementation schemes for dual-coil contactors at present. One of them is a mechanical implementation scheme, which is usually implemented by two sets of coils in combination with micro switches. One set of coils carries a large current and the other set carries a small current. That is, the attraction coil that carries a large current performs the attraction action, and the holding coil that carries a small current performs the holding action. After the attraction action is completed, the micro switch is switched to cut off the attraction coil to reduce the power consumption of the whole machine; the other is an electronic implementation scheme, which is usually implemented by two sets of coils in combination with a circuit board. One set of coils carries a large current and the other set carries a small current. When the product is powered on, a pulse signal with a duration of T will be triggered through the differential circuit. The pulse signal can make the attraction coil act for T time and then disconnect.

[0003] However, when using a mechanical implementation, the switching of the micro switch will generate an arc, which will seriously affect the life of the micro switch and reduce the life cycle of the entire machine. Since the electronic implementation solution requires the use of a circuit board, it can only be controlled using DC voltage, which has certain limitations. Utility Model Content

[0004] In view of the above problems, the present application provides a dual-coil contactor to solve the above technical problems.

[0005] In a first aspect, the present application provides a dual-coil contactor, which includes a pull-in coil circuit, a holding coil circuit, a power supply module, a sampling and comparison module, a drive module, and a delay module, wherein:

[0006] A power module is connected to the external power supply, the pull-in coil circuit, and the holding coil circuit, and is used to generate a DC voltage from the external power supply voltage to electrically conduct the holding coil circuit, and to step down the DC voltage to obtain a power supply voltage; wherein the external power supply is an AC power supply or a DC power supply;

[0007] The sampling and comparison module is connected to the power module and is used to sample the DC voltage. When the sampled voltage is greater than a preset voltage threshold, the operating voltage is generated according to the power supply voltage.

[0008] A driving module connected to the power module, the sampling and comparison module, and the pull-in coil circuit, for controlling the pull-in coil circuit to be electrically conductive based on the DC voltage in response to the power supply voltage and the operating voltage, and controlling the pull-in coil circuit to be electrically disconnected in response to the trigger signal;

[0009] The delay module is connected to the pull-in coil circuit and the driving module, and is used to generate a trigger signal when the duration of the electrical conduction of the pull-in coil circuit reaches a preset duration.

[0010] In a possible implementation of the present application, the sampling and comparison module includes a voltage sampling unit, a comparison unit, and a switch unit;

[0011] A voltage sampling unit is used to sample the DC voltage to obtain a sampled voltage;

[0012] A comparison unit, configured to generate a driving voltage and output it to the switch unit when the sampling voltage is greater than a preset voltage threshold;

[0013] The switch unit is configured to be turned on in response to the driving voltage to generate an operating voltage according to the power supply voltage.

[0014] In a possible implementation of the present application, the voltage sampling unit includes a first resistance circuit and a second resistance circuit, and the comparison unit includes a voltage regulator;

[0015] The first end of the first resistance circuit is connected to the power supply module to receive the DC voltage, the second end of the first resistance circuit is connected to the first end of the second resistance circuit and the comparison terminal of the voltage regulator to output the sampling voltage, and the second end of the second resistance circuit is connected to the ground terminal;

[0016] A first terminal of the voltage stabilizer is connected to the switch unit to output a driving voltage, and a second terminal of the voltage stabilizer is connected to the ground terminal.

[0017] In a possible implementation of the present application, the switching unit includes a first switching tube, the control end of the first switching tube is connected to the comparison unit to access the driving voltage, the first end of the first switching tube is connected to the power supply module to access the power supply voltage, and the second end of the first switching tube is connected to the driving module to output the operating voltage.

[0018] In a possible implementation of the present application, the driving module includes a power-on trigger unit, a switch trigger unit, and a maintenance trigger unit;

[0019] a power-on trigger unit, configured to generate a first high-level signal in response to a power supply voltage at power-on and output it to the switch trigger unit;

[0020] a switch trigger unit, configured to generate a first low-level signal in response to the first high-level signal or the second high-level signal from the sustain trigger unit, and generate a control signal according to the operating voltage in response to the first low-level signal, output to the pull-in coil circuit, so as to control the electrical conduction of the pull-in coil circuit;

[0021] The sustain trigger unit is configured to generate a second high level signal in response to the power supply voltage.

[0022] In a possible implementation of the present application, the power-on trigger unit includes a first capacitor and a first resistor, the first end of the first capacitor is connected to the power supply module to access the power supply voltage, the second end of the first capacitor is connected to the first end of the first resistor, and the second end of the first resistor is connected to the switch trigger unit to output a first high-level signal.

[0023] In one possible implementation of the present application, the switch trigger unit includes a second switch tube and a third switch tube, a control end of the second switch tube is connected to the power-on trigger unit and the sustain trigger unit to receive the first high-level signal or the second high-level signal, a second end of the second switch tube is connected to the ground end, and a first end of the second switch tube is connected to the control end of the third switch tube to output the first low-level signal;

[0024] The first end of the third switch tube is connected to the sampling and comparing module to access the working voltage, and the second end of the third switch tube is connected to the pull-in coil loop to output the control signal.

[0025] In a possible implementation of the present application, the maintenance trigger unit includes a fourth switch tube, the control end of the fourth switch tube is connected to the power supply module through the second resistor to access the power supply voltage, and is connected to the first end of the second switch tube through the third resistor, the first end of the fourth switch tube is connected to the power supply module to access the power supply voltage, the second end of the fourth switch tube is connected to the ground end through the fourth resistor and the fifth resistor connected in series, and the connection node of the fourth resistor and the fifth resistor is connected to the control end of the second switch tube to output a second high-level signal.

[0026] In a possible implementation of the present application, the pull-in coil circuit includes a pull-in coil, a fifth switch tube and a current sampling resistor, and the delay module includes a current conducting resistor, a charging capacitor and a sixth switch tube;

[0027] The first end of the pull-in coil is connected to the power supply module to access the DC voltage, the second end of the pull-in coil is connected to the first end of the fifth switch tube, the control end of the fifth switch tube is connected to the second end of the third switch tube, the second end of the fifth switch tube is connected to the first end of the current-conducting resistor and the grounded current sampling resistor, the second end of the current-conducting resistor is connected to the control end of the sixth switch tube and the grounded charging capacitor, the first end of the sixth switch tube is connected to the control end of the second switch tube, and the second end of the sixth switch tube is connected to the ground end.

[0028] In a possible implementation of the present application, the power module includes a rectifier unit and a step-down unit;

[0029] The rectifier unit is used to rectify the external power supply voltage to obtain a DC voltage;

[0030] The step-down unit is used to step down the DC voltage to obtain the power supply voltage.

[0031] From the above content, it can be concluded that this application has the following beneficial effects:

[0032] The dual-coil contactor provided by the present application converts the external power supply voltage from the external power supply into a DC voltage through a power supply module. The external power supply can be an AC power supply or a DC power supply, and the DC voltage is stepped down to obtain the power supply voltage. The DC voltage is sampled by a sampling and comparison module, and when the sampled voltage is greater than a preset voltage threshold, the sampling and comparison module generates an operating voltage according to the power supply voltage, so that the driving module can control the electrical conduction of the attraction coil circuit based on the DC voltage in response to the power supply voltage and the operating voltage, and when the duration of the electrical conduction of the attraction coil circuit reaches a preset duration, a trigger signal is generated by the delay module to control the electrical disconnection of the attraction coil circuit, so that the coil circuit is maintained in a conductive state, thereby ensuring low power consumption. Compared with the electronic implementation scheme in the related art that can only use DC voltage for control, even if the external power supply is an AC power supply, the dual-coil contactor provided by the present application can also convert the AC voltage of the AC power supply into a DC voltage for control through the power supply module, which greatly expands the application range of the dual-coil contactor, ensures the reliability of the dual-coil contactor, and extends its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 This is a structural diagram of a double-coil contactor provided in an embodiment of the present application;

[0035] Figure 2 This is a schematic diagram of the structure of the sampling and comparison module provided in the embodiment of the present application;

[0036] Figure 3 This is a schematic diagram of a circuit principle of the sampling and comparison module provided in an embodiment of the present application;

[0037] Figure 4 This is a schematic structural diagram of a driving module provided in an embodiment of the present application;

[0038] Figure 5 This is a schematic diagram of a circuit principle of a driving module provided in an embodiment of the present application;

[0039] Figure 6 This is a schematic diagram of the structure of the power module provided in an embodiment of the present application;

[0040] Figure 7 This is a schematic diagram of a circuit principle of a power supply module provided in an embodiment of the present application;

[0041] Figure 8 This is another structural diagram of the power module provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The embodiments of the present application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0043] In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0044] In the embodiments of the present application, it should be noted that, in this document, relational terms such as first and second, etc., are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0045] Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that an article or device comprising a list of elements includes not only those elements but also other elements not explicitly listed or inherent to such article or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the article or device comprising the element.

[0046] In the description of the embodiments of this application, words such as "example" or "for example" are used to indicate an example, illustration, or description. Any embodiment or design described as "for example" or "for example" in the embodiments of this application is not to be construed as being preferred or having more advantages than another embodiment or design. The use of words such as "example" or "for example" is intended to clearly present relative concepts.

[0047] In addition, in the embodiments of the present application, "plurality" refers to two or more. In view of this, in the embodiments of the present application, "plurality" can also be understood as "at least two". "At least one" can be understood as one or more, for example, one, two, or more. For example, "including at least one" means including one, two, or more, and does not limit which ones are included. For example, "including at least one of A, B, and C" means including A, B, C, A and B, A and C, B and C, or A, B, and C.

[0048] It should be noted that in the embodiments of the present application, "connection" can be understood as electrical connection, and the connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be either a direct connection between A and B or an indirect connection between A and B through one or more other electrical components.

[0049] The first electrode / first end of each transistor used in the embodiments of the present application is one of the source and the drain, and the second electrode / second end of each transistor is the other of the source and the drain. Since the source and drain of the transistor can be symmetrical in structure, the source and drain can be structurally indistinguishable, that is, the first electrode / first end and the second electrode / second end of the transistor in the embodiments of the present application can be structurally indistinguishable. For example, in the case where the transistor is a P-type transistor, the first electrode / first end of the transistor is the source, and the second electrode / second end is the drain; for example, in the case where the transistor is an N-type transistor, the first electrode / first end of the transistor is the drain, and the second electrode / second end is the source.

[0050] In the circuit structure provided in the embodiments of the present application, the first node, the second node and other nodes do not represent actual components, but represent the junction points of related couplings in the circuit diagram. That is, these nodes are nodes formed by the equivalent junction points of related couplings in the circuit diagram.

[0051] The embodiment of the present application provides a dual-coil contactor, which is described in detail below.

[0052] See also Figure 1 , Figure 1 1 is a structural diagram of a dual-coil contactor provided in an embodiment of the present application. The dual-coil contactor 100 may include an attraction coil circuit 110, a holding coil circuit 120, a power supply module 130, a sampling and comparison module 140, a drive module 150 and a delay module 160.

[0053] Among them, the power supply module 130 can be connected to the external power supply 200, the attraction coil circuit 110 and the holding coil circuit 120 respectively, and is used to connect the external power supply voltage to generate a DC voltage to make the holding coil circuit 120 electrically conductive, and to step down the DC voltage to obtain the power supply voltage; wherein, the external power supply 200 is an AC power supply or a DC power supply.

[0054] The sampling and comparison module 140 can be connected to the power supply module 130 to sample the DC voltage and generate an operating voltage according to the power supply voltage when the sampled voltage is greater than a preset voltage threshold.

[0055] The driving module 150 can be connected to the power supply module 130, the sampling and comparison module 140 and the attraction coil circuit 110, and is used to control the attraction coil circuit 110 to be electrically conductive based on the DC voltage in response to the power supply voltage and the operating voltage, and to control the attraction coil circuit 110 to be electrically disconnected in response to the trigger signal.

[0056] The delay module 160 may be connected to the pull-in coil circuit 110 and the driving module 150 , and configured to generate a trigger signal when the duration of electrical conduction of the pull-in coil circuit 110 reaches a preset duration.

[0057] The external power supply 200 can be either an AC power supply or a DC power supply. For example, the external power supply 200 can be 220V AC mains power, or it can be DC power obtained by rectifying, filtering, and reducing the voltage of the 220V AC mains power. The type of the external power supply 200, i.e., the external power supply voltage connected to the power module 130, can be determined based on the actual application scenario and is not limited here.

[0058] In the embodiment of the present application, the power module 130 can rectify the external power supply voltage to generate a DC voltage, which can be output to the sampling and comparison module 140, the pull-in coil circuit 110, and the holding coil circuit 120. At this time, the holding coil circuit 120 can be directly electrically conductive based on the DC voltage. Since the holding coil is a low-current coil, the motor has not yet started.

[0059] At the same time, the power module 130 can also perform voltage reduction processing on the DC voltage to generate a power voltage which is output to the sampling and comparison module 140 and the driving module 150 respectively.

[0060] The sampling and comparison module 140 can sample the DC voltage to obtain a sampled voltage, and then compare the sampled voltage with a preset voltage threshold. When the sampled voltage is greater than the preset voltage threshold, an operating voltage is generated based on the power supply voltage and output to the driving module 150.

[0061] When powered on, the driver module 150 can trigger the electrical conduction of the pull-in coil circuit 110 in response to the received power supply voltage and operating voltage. Since the pull-in coil circuit 110 is connected to the DC voltage from the power module 130, current flows through the pull-in coil, generating electromagnetic force, driving the contacts to close, thereby engaging the pull-in coil circuit 110.

[0062] When the pull-in coil circuit 110 is electrically conductive, the delay module 160 operates. When the duration of the electrical conduction of the pull-in coil circuit 110 reaches a preset duration, the delay module 160 generates a trigger signal and outputs it to the driver module 150, so that the driver module 150 can control the pull-in coil circuit 110 to be electrically disconnected in response to the trigger signal. At this time, since a certain current, i.e., a certain electromagnetic force, is maintained on the coil, the power of the entire machine can be reduced and the contacts can remain in a closed state, ensuring stable operation of the entire machine.

[0063] The preset duration can be any value such as 20ms, 50ms, etc., and can be set according to the parameters of the pull-in coil, the DC voltage, and the parameters of other electronic components involved in the actual application scenario, and is not limited here.

[0064] The dual-coil contactor 100 provided in the embodiment of the present application converts the external power supply voltage from the external power supply 200 into a DC voltage through the power supply module 130. The external power supply 200 can be an AC power supply or a DC power supply, and the DC voltage is stepped down to obtain the power supply voltage. The DC voltage is sampled by the sampling and comparison module 140, and when the sampled voltage is greater than a preset voltage threshold, the sampling and comparison module 140 generates an operating voltage according to the power supply voltage, so that the driving module 150 can control the pull-in coil circuit 110 to be electrically conductive based on the DC voltage in response to the power supply voltage and the operating voltage, and the pull-in coil circuit 110 is electrically conductive based on the DC voltage. When the duration of electrical conduction reaches a preset duration, a trigger signal is generated by the delay module 160 to control the electrical disconnection of the attraction coil circuit 110, so that the holding coil circuit 120 is maintained in a conductive state, thereby ensuring low power consumption. Compared with the electronic implementation scheme in the related art that can only use DC voltage for control, even if the external power supply is an AC power supply, the dual-coil contactor 100 provided in this application can also convert the AC voltage of the AC power supply into a DC voltage for control through the power supply module 130, which greatly expands the application range of the dual-coil contactor 100, ensures the reliability of the dual-coil contactor 100, and extends its service life.

[0065] Next, continue to Figure 1 The modules shown and the specific implementation methods that may be used in practical applications are described in detail.

[0066] like Figure 2As shown, in some embodiments of the present application, the sampling and comparison module 140 may include a voltage sampling unit 1401, a comparison unit 1402 and a switch unit 1403; wherein, the voltage sampling unit 1401 can be used to sample the DC voltage to obtain a sampling voltage; the comparison unit 1402 can be used to generate a driving voltage to output to the switch unit 1403 when the sampling voltage is greater than a preset voltage threshold; the switch unit 1403 can be used to turn on in response to the driving voltage to generate an operating voltage according to the power supply voltage.

[0067] In the embodiment of the present application, the preset voltage threshold can be determined according to the actual application scenario; the voltage sampling unit 1401 can adopt any existing voltage sampling circuit, including but not limited to a resistor voltage divider circuit; the comparison unit 1402 can adopt any existing comparator, comparison circuit, voltage regulator, etc.; the switching unit 1403 can adopt a switching control circuit of any existing controllable switching device, wherein the controllable switching device includes but is not limited to transistors such as triodes and metal-oxide-semiconductor field-effect transistors (MOSFETs).

[0068] As an example, the voltage sampling unit 1401 may include a first resistance circuit and a second resistance circuit connected in series, wherein the first resistance circuit can be connected to the power supply module 130 to access the DC voltage, and the connection node between the first resistance circuit and the second resistance circuit can be connected to the comparison unit 1402 to output the sampled voltage.

[0069] It can be understood that the first resistance circuit and the second resistance circuit can respectively include at least one series resistor, and the number of series resistors in the first resistance circuit and the second resistance circuit can be selected according to the actual application scenario and is not limited here.

[0070] The switching unit 1403 may include a first switching tube, the control end of the first switching tube is connected to the comparison unit 1402 to access the driving voltage, the first end of the first switching tube is connected to the power supply module 130 to access the power supply voltage, and the second end of the first switching tube is connected to the driving module 150 to output the operating voltage.

[0071] It is understandable that the first switch tube can be a switching transistor such as a triode, a MOS tube, or a thyristor.

[0072] like Figure 3 As shown, in a specific implementation, the first resistance circuit includes a fifteenth resistor R15, the second resistance circuit includes a sixteenth resistor R16, the comparison unit 1402 includes a comparator U1, and the switch unit 1403 includes a first PNP-type transistor Q1. The specific circuit connection structure is as follows:

[0073] A first end of the fifteenth resistor R15 is connected to the power module 130 to receive the DC voltage V_P. A second end of the fifteenth resistor R15 is respectively connected to pin 2 of the comparator U1 and the first end of the sixteenth resistor R16. A second end of the sixteenth resistor R16 is connected to the ground terminal GND. Pin 3 of the comparator U1 is also connected to the ground terminal GND. A fifth capacitor C5 is connected in parallel between pins 2 and 3 of the comparator U1. Pin 1 of the comparator U1 is connected to the emitter of the first transistor Q1 via a thirteenth resistor R13 and to the base of the first transistor Q1 via a fourteenth resistor R14. The collector of the first transistor Q1 is connected to a grounded fourth capacitor C4. The emitter of the first transistor Q1 is also connected to the power module 130 to receive the power supply voltage VCC, and the collector is also connected to the driver module 150 to output the operating voltage VDD.

[0074] Assuming that the preset voltage threshold is 2.5V, the fifteenth resistor R15 and the sixteenth resistor R16 are connected in series to divide the DC voltage V_P, and the sampling voltage V_Sam = V_P*R16 / (R15+R16). When V_Sam is greater than 2.5V, the driving voltage Vb generated by the first pin of the comparator U1 is 2V. At this time, the first transistor Q1 is turned on in response to the driving voltage Vb. Without considering the transistor voltage drop, the operating voltage VDD output by the collector is equal to the power supply voltage VCC connected to the emitter.

[0075] On the contrary, when V_Sam is less than 2.5V, the driving voltage Vb generated by the first pin of the comparator U1 is 12V. At this time, the first transistor Q1 is cut off in response to the driving voltage Vb, that is, the first transistor Q1 is not conducting. At this time, the circuit does not work and no operating voltage VDD is generated.

[0076] like Figure 4 As shown, in some embodiments of the present application, the driving module 150 may include a power-on trigger unit 1501, a switch trigger unit 1502 and a maintenance trigger unit 1503; wherein, the power-on trigger unit 1501 can be used to generate a first high-level signal in response to the power supply voltage at power-on and output it to the switch trigger unit 1502; the switch trigger unit 1502 can be used to respond to the first high-level signal or the second high-level signal from the maintenance trigger unit 1503, generate a first low-level signal, and in response to the first low-level signal, generate a control signal according to the operating voltage and output it to the attraction coil circuit 110 to control the electrical conduction of the attraction coil circuit 110; the maintenance trigger unit 1503 can be used to generate a second high-level signal in response to the power supply voltage.

[0077] In an embodiment of the present application, the power-on trigger unit 1501 can be used to generate a first high-level signal and output it to the switch trigger unit 1502 at the moment when the power supply voltage is powered on, so that the switch trigger unit 1502 can respond to the first high-level signal to turn on and then generate a first low-level signal, and then respond to the first low-level signal to generate a control signal according to the working voltage and output it to the attraction coil circuit 110, so that the attraction coil circuit 110 can be electrically conductive; at the same time, the maintenance trigger unit 1503 can generate a second high-level signal and output it to the switch trigger unit 1502 according to the stable power supply voltage after power-on, so that the switch trigger unit 1502 can still respond to the second high-level signal to turn on and then generate a first low-level signal in the absence of the first high-level signal, and then respond to the first low-level signal to generate a control signal according to the working voltage and output it to the attraction coil circuit 110, so that the attraction coil circuit 110 maintains an electrically conductive state.

[0078] In some embodiments of the present application, the power-on trigger unit 1501 may include a first capacitor and a first resistor, the first end of the first capacitor is connected to the power supply module 130 to access the power supply voltage, the second end of the first capacitor is connected to the first end of the first resistor, and the second end of the first resistor is connected to the switch trigger unit 1502 to output a first high-level signal.

[0079] Switch trigger unit 1502 may include a second switch and a third switch. The control terminal of the second switch is connected to power-on trigger unit 1501 and sustain trigger unit 1503 to receive the first high-level signal or the second high-level signal. The second terminal of the second switch is connected to ground. The first terminal of the second switch is connected to the control terminal of the third switch to output a first low-level signal. The first terminal of the third switch is connected to sampling and comparison module 140 to receive the operating voltage, and the second terminal of the third switch is connected to the pull-in coil loop 110 to output the control signal.

[0080] The maintenance trigger unit 1503 may include a fourth switch tube, the control end of the fourth switch tube is connected to the power supply module 130 through the second resistor to access the power supply voltage, and is connected to the first end of the second switch tube through the third resistor, the first end of the fourth switch tube is connected to the power supply module 130 to access the power supply voltage, the second end of the fourth switch tube is connected to the ground end through the fourth resistor and the fifth resistor connected in series, and the connection node of the fourth resistor and the fifth resistor is connected to the control end of the second switch tube to output a second high-level signal.

[0081] In the embodiment of the present application, the second switch tube, the third switch tube and the fourth switch tube can be selected from switching transistors such as triodes, MOS tubes, thyristors, etc., and can be selected according to the actual application scenario and are not limited here.

[0082] See also Figure 5In a specific implementation, the second switch tube is an NPN type second transistor Q2, the third switch tube is a PNP type third transistor Q3, and the fourth switch tube is a PNP type fourth transistor Q4. The specific circuit connection structure is as follows:

[0083] The first capacitor C1 is connected to the power supply voltage VCC and is connected in series with the first resistor R1 to the base of the second transistor Q2. The emitter of the second transistor Q2 is connected to the ground terminal GND and its base is connected via a fifth resistor R5. The collector of the second transistor Q2 is connected to the base of the third transistor Q3 via a seventh diode D7 and a seventh resistor R7. The emitter of the third transistor Q3 is connected to the sampling and comparison module 140 to receive the operating voltage VDD. The collector of the third transistor Q3 is connected to the pull-in coil loop 110 via a sixth resistor R6. Simultaneously, the second resistor R2 and the third resistor R3 are connected in series to divide the power supply voltage VCC. The third resistor R3 is also connected to the collector of the second transistor Q2. The junction point between the second resistor R2 and the third resistor R3 is connected to the base of the fourth transistor Q4. The emitter of the fourth transistor Q4 is also connected to the power supply module 130 to receive the power supply voltage VCC. The collector of the fourth transistor Q4 is connected to the fifth resistor R5 via the fourth resistor R4.

[0084] When the power supply voltage VCC is powered on, a step signal is generated. At this time, the first capacitor C1 is instantaneously turned on in response to the step signal, and current flows through the first resistor R1, causing the voltage at the VB node to increase, thereby generating a first high-level signal. This increases the base voltage of the second transistor Q2, turning on the second transistor Q2. Since the emitter of the second transistor Q2 is connected to the ground terminal GND, the voltage at the VC node is pulled down to ground, thereby generating a first low-level signal that is output to the base of the third transistor Q3. As a result, the third transistor Q3 is turned on in response to the first low-level signal. The power supply voltage VDD generates a control signal via the sixth resistor R6, which is output to the pull-in coil circuit 110, driving the pull-in coil circuit 110 to be attracted.

[0085] At the same time, after power-on, the second resistor R2 and the third resistor R3 divide the voltage so that the fourth transistor Q4 is turned on. The fourth resistor R4 and the fifth resistor R5 divide the power supply voltage VCC so that the VB node is maintained at a high level state and the VC node is maintained at a low level state, so that the second transistor Q2 and the fourth transistor Q4 reach a balance. The fluctuation of the power supply voltage VCC will not affect this balance state, and the third transistor Q3 can be maintained turned on, ensuring that the attraction coil loop 110 is electrically conductive.

[0086] Please continue reading Figure 5In some embodiments of the present application, the pull-in coil circuit 110 may include a pull-in coil TC1, a fifth switch tube and a current sampling resistor R12, and the delay module 160 may include a current conducting resistor R11, a charging capacitor C3 and a sixth switch tube; the first end of the pull-in coil TC1 is connected to the power supply module 130 to access the DC voltage V_P, the second end of the pull-in coil TC1 is connected to the first end of the fifth switch tube, the control end of the fifth switch tube is connected to the second end of the third switch tube, the second end of the fifth switch tube is connected to the first end of the current conducting resistor R11 and the grounded current sampling resistor R12, the second end of the current conducting resistor R11 is connected to the control end of the sixth switch tube and the grounded charging capacitor C3, the first end of the sixth switch tube is connected to the control end of the second switch tube, and the second end of the sixth switch tube is connected to the ground terminal GND.

[0087] In the embodiment of the present application, the fifth switching transistor is an N-type MOS transistor Q5, and the sixth switching transistor is an NPN-type sixth transistor Q6. Specifically, one end of the pull-in coil TC1 is connected to the power module 130 to receive the DC voltage V_P, and the other end is connected to the drain of the MOS transistor Q5. The gate of the MOS transistor Q5 is connected to the collector of the third transistor Q3 to receive the control signal. The source of the MOS transistor Q5 is connected to the ground terminal GND through the current sampling resistor R12. At the same time, the source of the MOS transistor Q5 is also connected to the base of the sixth transistor Q6 through the current conducting resistor R11. The emitter of the sixth transistor Q6 is connected to the ground terminal GND. The charging capacitor C3 is connected in parallel to the base and emitter of the sixth transistor Q6. The collector of the sixth transistor Q6 is connected to the base of the second transistor Q2.

[0088] When the pull-in coil circuit 110 is electrically conductive, the DC voltage V_P increases the current on the MOS transistor Q5 through the pull-in coil TC1, thereby increasing the current flowing through the current sampling resistor R12. The high-level voltage VI of the current sampling resistor R12 is raised, and the high-level voltage VI charges the charging capacitor C3 through the conducting resistor R11. Assuming that the current I=10A, the high-level voltage VI=I*R12=1.5V, and the charging capacitor C3 is 22uf, the charging capacitor C3 is charged to 0.7V in about 125ms, that is, the sixth third After 125 ms, the base voltage of transistor Q6 reaches 0.7 V, and the sixth transistor Q6 is turned on. Since the emitter of the sixth transistor Q6 is connected to the ground terminal GND, the voltage at the VB node is pulled down to ground. The second transistor Q2 is turned off, and the voltage at the VC node is raised. The third transistor Q3 is turned off, and stops outputting the control signal to the MOS transistor Q5. As a result, the MOS transistor Q5 is turned off, and the pull-in coil loop 110 is electrically disconnected. The holding coil HC1 remains turned on based on the DC voltage VP, thereby achieving the purpose of low power consumption.

[0089] It can be understood that the preset time length can be adjusted by adjusting the current size of the attraction coil circuit 110, the size of the high voltage VI, the parameters of the charging capacitor C3, etc. The preset time length should not be too long. If it is too long, it may cause serious heating of the attraction coil and affect the product life. The preset time length should not be too short. If it is too short, it may cause unreliable contact attraction. Therefore, the preset time length can be determined according to the actual application scenario and is not limited here.

[0090] like Figure 6 As shown, in some embodiments of the present application, the power module 130 may include a rectifier unit 1301 and a step-down unit 1302; the rectifier unit 1301 can be used to rectify the external power supply voltage to obtain a DC voltage; the step-down unit 1302 can be used to step-down the DC voltage to obtain a power supply voltage.

[0091] In the embodiment of the present application, the rectifier unit 1301 can adopt any existing rectifier circuit, including but not limited to a rectifier bridge circuit, a full-wave rectifier, etc., and the buck unit 1302 can adopt any existing buck circuit, including but not limited to a linear buck circuit, a switching power supply BUCK buck circuit, etc.

[0092] Please participate Figure 7 In a specific implementation, the rectifier unit 1301 includes a rectifier bridge consisting of a first diode Q1, a second diode D2, a third diode D3, and a fourth diode D4. The step-down unit 1302 includes a voltage-stabilizing diode ZD1 and a seventh transistor Q7. Specifically, the external power supply 200 is connected through the first socket P1. A varistor RV1 is connected to the front end of the rectifier bridge to provide overvoltage protection for the circuit. A large electrolytic capacitor CE1 is connected to the rear end of the rectifier bridge to ensure a stable output DC voltage V_P.

[0093] The collector of the seventh transistor Q7 is connected to the positive electrode of the large electrolytic capacitor CE1 through the eighth resistor R8, the base of the seventh transistor Q7 is connected to the ninth resistor R9 and the cathode of the Zener diode ZD12, the anode of the Zener diode ZD1 is connected to the ground terminal GND and is connected to the ninth resistor R9 and the eighth resistor R8 through the second capacitor C2, and the emitter of the seventh transistor Q7 is connected to the sixth capacitor C6 and outputs the power supply voltage VCC.

[0094] In the embodiment of the present application, the characteristics of transistors are utilized to achieve voltage reduction. By adjusting the control current of the seventh transistor Q7, the off-state voltage (Vbe) of the seventh transistor Q7 is proportional to the output voltage (power supply voltage VCC). Thus, when the input voltage (DC voltage V_P) increases, the control current of the seventh transistor Q7 also increases, thereby reducing the off-state voltage of the seventh transistor Q7 and the output voltage, thereby achieving the purpose of voltage reduction.

[0095] Understandably, Figure 8 As shown, in some embodiments of the present application, the power supply module 130 may further include an electromagnetic compatibility module 1303, which may be connected between the external power supply 200 and the rectifier unit 1301 to reduce the impact of external electromagnetic interference on the operation of the entire machine, and may also reduce the interference of the entire machine with other external devices during operation.

[0096] In the embodiment of the present application, the electromagnetic compatibility module 1303 may include any existing electromagnetic interference (EMI) circuit and electromagnetic susceptibility (EMS) circuit, which is not limited here.

[0097] It can be understood that the EMI circuit can reduce the interference caused by the whole machine to other devices in the environment due to the emission / discharge of electromagnetic waves, and the EMS circuit can improve the tolerance / immunity of the whole machine to external electromagnetic wave interference, thereby improving the reliability of the power module 130 and further improving the reliability of the whole machine.

[0098] The above is only a preferred embodiment of the present application and does not constitute any form of limitation to the present application. Although the present application has been disclosed as above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to equivalent embodiments using the technical contents disclosed above without departing from the scope of the technical solution of the present application. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A double-coil contactor, characterized in that: include: Pull-in coil circuit; Maintain coil loop; a power module connected to an external power supply, the pull-in coil circuit, and the holding coil circuit, for receiving an external power supply voltage to generate a DC voltage to electrically conduct the holding coil circuit, and for stepping down the DC voltage to obtain a power supply voltage; wherein the external power supply is an AC power supply or a DC power supply; a sampling and comparison module, connected to the power module, for sampling the DC voltage and generating an operating voltage according to the power supply voltage when the sampled voltage is greater than a preset voltage threshold; a driving module connected to the power supply module, the sampling and comparing module, and the pull-in coil circuit, configured to control the pull-in coil circuit to be electrically conductive based on the DC voltage in response to the power supply voltage and the operating voltage, and to control the pull-in coil circuit to be electrically disconnected in response to a trigger signal; The delay module is connected to the pull-in coil circuit and the driving module, and is used to generate the trigger signal when the duration of the electrical conduction of the pull-in coil circuit reaches a preset duration.

2. The double-coil contactor according to claim 1, characterized in that: The sampling and comparison module includes a voltage sampling unit, a comparison unit and a switch unit; The voltage sampling unit is used to sample the DC voltage to obtain the sampled voltage; The comparison unit is configured to generate a driving voltage and output it to the switch unit when the sampling voltage is greater than the preset voltage threshold; The switch unit is configured to be turned on in response to the driving voltage to generate the operating voltage according to the power supply voltage.

3. The double-coil contactor according to claim 2, characterized in that: The voltage sampling unit includes a first resistance circuit and a second resistance circuit, and the comparison unit includes a voltage stabilizer; The first end of the first resistance circuit is connected to the power supply module to receive the DC voltage, the second end of the first resistance circuit is connected to the first end of the second resistance circuit and the comparison terminal of the voltage regulator to output the sampled voltage, and the second end of the second resistance circuit is connected to the ground terminal; A first terminal of the voltage regulator is connected to the switch unit to output the driving voltage, and a second terminal of the voltage regulator is connected to the ground terminal.

4. The double-coil contactor according to claim 2, characterized in that: The switching unit includes a first switching tube, a control end of the first switching tube is connected to the comparison unit to access the driving voltage, a first end of the first switching tube is connected to the power supply module to access the power supply voltage, and a second end of the first switching tube is connected to the driving module to output the operating voltage.

5. The double-coil contactor according to claim 1, characterized in that: The driving module includes a power-on trigger unit, a switch trigger unit and a maintenance trigger unit; The power-on trigger unit is configured to generate a first high-level signal in response to the power supply voltage during power-on and output it to the switch trigger unit; The switch trigger unit is configured to generate a first low-level signal in response to the first high-level signal or the second high-level signal from the sustain trigger unit, and generate a control signal according to the operating voltage in response to the first low-level signal and output it to the pull-in coil circuit to control the electrical conduction of the pull-in coil circuit; The sustain trigger unit is configured to generate the second high level signal in response to the power supply voltage.

6. The double-coil contactor according to claim 5, characterized in that: The power-on trigger unit includes a first capacitor and a first resistor, the first end of the first capacitor is connected to the power supply module to access the power supply voltage, the second end of the first capacitor is connected to the first end of the first resistor, and the second end of the first resistor is connected to the switch trigger unit to output the first high-level signal.

7. The double-coil contactor according to claim 5, characterized in that: The switch trigger unit includes a second switch tube and a third switch tube, wherein the control end of the second switch tube is connected to the power-on trigger unit and the sustain trigger unit to receive the first high-level signal or the second high-level signal, the second end of the second switch tube is connected to the ground end, and the first end of the second switch tube is connected to the control end of the third switch tube to output the first low-level signal; The first end of the third switch tube is connected to the sampling and comparing module to access the working voltage, and the second end of the third switch tube is connected to the pull-in coil loop to output the control signal.

8. The double-coil contactor according to claim 7, characterized in that: The maintenance trigger unit includes a fourth switch tube, the control end of the fourth switch tube is connected to the power supply module through a second resistor to access the power supply voltage, and is connected to the first end of the second switch tube through a third resistor. The first end of the fourth switch tube is connected to the power supply module to access the power supply voltage, and the second end of the fourth switch tube is connected to the ground end through a fourth resistor and a fifth resistor connected in series, and the connection node of the fourth resistor and the fifth resistor is connected to the control end of the second switch tube to output the second high-level signal.

9. The double-coil contactor according to claim 7, characterized in that: The pull-in coil circuit includes a pull-in coil, a fifth switch tube and a current sampling resistor, and the delay module includes a current conducting resistor, a charging capacitor and a sixth switch tube; The first end of the pull-in coil is connected to the power module to receive the DC voltage, the second end of the pull-in coil is connected to the first end of the fifth switch tube, the control end of the fifth switch tube is connected to the second end of the third switch tube, the second end of the fifth switch tube is connected to the first end of the current-conducting resistor and the grounded current sampling resistor, the second end of the current-conducting resistor is connected to the control end of the sixth switch tube and the grounded charging capacitor, the first end of the sixth switch tube is connected to the control end of the second switch tube, and the second end of the sixth switch tube is connected to the ground end.

10. The double-coil contactor according to any one of claims 1 to 9, characterized in that: The power module includes a rectifier unit and a step-down unit; The rectifier unit is used to rectify the external power supply voltage to obtain the DC voltage; The step-down unit is used to step down the DC voltage to obtain the power supply voltage.

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