Direct-current buck circuit, brake mechanism, and electric motor

Abstract

The present application belongs to the technical field of brake mechanisms. Provided are a direct-current buck circuit, a brake mechanism, and an electric motor. The direct-current buck circuit comprises an input circuit, an energy storage inductor and an output circuit, wherein the input circuit, the energy storage inductor and the output circuit are electrically connected in sequence; the input circuit is used for connecting to a power source; the energy storage inductor is used for performing opening and closing control over a brake-shoe brake by means of a magnetic field; and the output circuit is used for connecting to a load. By using the solution, an energy storage inductor in a direct-current buck circuit can replace a brake coil which is connected to a load end of a direct-current buck circuit in the prior art, that is, it is not necessary to provide a brake coil in a brake mechanism, which is conducive to reducing the cost of the brake mechanism and improving the working stability.

Description

DC step-down circuit, brake mechanism and motor

[0001] This application claims priority to Chinese patent application No. 202310802785.3, filed on June 30, 2023, entitled “DC step-down circuit, brake mechanism and motor”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of brake mechanisms, and in particular to a DC step-down circuit, a brake mechanism, and a motor. Background Art

[0003] The holding brake acts as a brake for the servo motor. It's also called a holding brake. When the holding brake is engaged, it locks the motor in place while it's stationary and de-energized, preventing it from moving due to external forces. When the holding brake is released, it allows the motor to operate normally while it's energized.

[0004] The brake mechanism typically consists of a DC step-down circuit with adjustable voltage and a brake shoe. The load terminal of the DC step-down circuit is connected to a brake coil, which typically consists of a brake wheel and brake shoe. When the brake coil is energized, it generates a magnetic field that separates the brake wheel and brake shoe, placing the brake mechanism in the released state. When the brake coil is deenergized, no magnetic field is generated around it, holding the brake wheel and brake shoe together. The brake mechanism is in the engaged state.

[0005] However, in the related art, the number of electronic components in the brake mechanism is large, which makes the brake mechanism costly.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a DC step-down circuit, a brake mechanism, and a motor, which can solve the problem in related technologies of high brake mechanism costs due to the large number of electronic components in the brake mechanism. The technical solution is as follows:

[0008] In a first aspect, the present application provides a DC step-down circuit, comprising an input circuit, an energy storage inductor, and an output circuit, wherein the input circuit, the energy storage inductor, and the output circuit are electrically connected in sequence;

[0009] The input circuit is used to access the power supply;

[0010] The energy storage inductor is used to control the opening and closing of the brake shoe brake through the magnetic field;

[0011] The output circuit is used for connecting to a load.

[0012] In a possible implementation, the energy storage inductor and the brake shoe brake belong to the same brake mechanism.

[0013] In a possible implementation, the input circuit and the output circuit are located on the same circuit board, the circuit board is spatially isolated from the brake mechanism, and two ends of the energy storage inductor are electrically connected to the input circuit and the output circuit respectively through wires.

[0014] In a possible implementation, the input circuit includes a first switching circuit and a freewheeling circuit;

[0015] The first connection end of the first switch circuit is electrically connected to the power supply;

[0016] The second connection end of the first switching circuit, the first connection end of the energy storage inductor and the output end of the freewheeling circuit are electrically connected;

[0017] The input end of the freewheeling circuit is electrically connected to the power supply and the output circuit respectively.

[0018] In a possible implementation, the output circuit includes a filter capacitor;

[0019] The first connection end of the filter capacitor is electrically connected to the second connection end of the energy storage inductor and the load respectively, and the second connection end of the filter capacitor is electrically connected to the input circuit and the load respectively.

[0020] In a possible implementation, the output circuit further includes a second switching circuit;

[0021] The first connection end of the second switch circuit is electrically connected to the first connection end of the filter capacitor, and the second connection end of the second switch circuit is electrically connected to the second connection end of the filter capacitor.

[0022] In a possible implementation, the load includes an auxiliary power supply.

[0023] In a possible implementation, the DC step-down circuit further includes a third switch circuit and a unidirectional current cutoff circuit;

[0024] The first connection end of the third switch circuit is electrically connected to the power supply;

[0025] The input end of the unidirectional cutoff circuit is electrically connected to the first output end of the output circuit;

[0026] The second connection end of the third switch circuit, the output end of the unidirectional cutoff circuit and the first end of the auxiliary power supply are electrically connected;

[0027] The second end of the auxiliary power supply is electrically connected to the second output end of the output circuit.

[0028] In a second aspect, a brake mechanism is provided, comprising a DC step-down circuit and a brake shoe brake as described in any one of the first aspect and possible implementations thereof.

[0029] In a possible implementation, the armature of the brake mechanism is located within a magnetic field range generated by an energy storage inductor of the DC step-down circuit.

[0030] In a possible implementation, the brake mechanism further includes an iron core, and the energy storage inductor is wound around the iron core.

[0031] In a third aspect, a motor is provided, comprising a brake mechanism as described in any one of the second aspect and possible implementations thereof.

[0032] The beneficial effects of the technical solution provided by the embodiments of the present application are:

[0033] In the solution provided in the embodiment of the present application, the DC step-down circuit includes an energy storage inductor, which controls the opening and closing of the brake shoe brake through a magnetic field, thereby realizing the switching of the brake mechanism between the released state and the brake state. Using this solution, the energy storage inductor in the DC step-down circuit can replace the brake coil connected to the load end of the DC step-down circuit in the related art. That is, there is no need to set up a brake coil in the brake mechanism. Moreover, the energy storage inductor directly acts on the brake shoe brake. Due to the characteristics of the energy storage inductor itself, there is no need to set up an additional sampling circuit in the DC step-down circuit. Therefore, compared with the brake mechanism in the related art, the brake mechanism using this DC step-down circuit can save at least one brake coil, which is beneficial to reducing the cost of the brake mechanism and improving working stability.

[0034] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] 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 ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0036] FIG1 is a schematic structural diagram of a brake mechanism provided in an embodiment of the present application;

[0037] FIG2 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0038] FIG3 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0039] FIG4 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0040] FIG5 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0041] FIG6 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0042] FIG7 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application;

[0043] FIG8 is a schematic structural diagram of a DC step-down circuit provided in an embodiment of the present application.

[0044] Legend: 1. Input circuit; 2. Energy storage inductor; 3. Output circuit; 4. Third switching circuit; 5. One-way current cutoff circuit; 11. First switching circuit; 12. Freewheeling circuit; 31. Filter capacitor; 32. Second switching circuit; 01. DC step-down circuit; 02. Shoe brake; 2a. First connection terminal of energy storage inductor; 2b. Second connection terminal of energy storage inductor; 11a. First connection terminal of first switching circuit; 11b. Second connection terminal of first switching circuit; 12a. Input terminal of freewheeling circuit; 12b. Output terminal of freewheeling circuit; 3a. First output terminal of output circuit; 3b. Second output terminal of output circuit; 31a. First connection terminal of filter capacitor; 31b. Second connection terminal of filter capacitor; 32a. First connection terminal of second switching circuit; 32b. Second connection terminal of second switching circuit; 4a. First connection terminal of third switching circuit; 4b. Second connection terminal of third switching circuit; 5a. Input end of the one-way cutoff circuit; 5b. Output end of the one-way cutoff circuit. DETAILED DESCRIPTION

[0045] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by persons of ordinary skill in the field to which this application belongs. The terms "first", "second", "third" and similar words used in the patent application specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Terms such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0046] The holding brake acts as a brake for the servo motor. It's also called a holding brake. When the holding brake is engaged, it locks the motor in place while it's stationary and de-energized, preventing it from moving due to external forces. When the holding brake is released, it allows the motor to operate normally while it's energized.

[0047] In related art, a brake mechanism typically comprises a voltage-adjustable DC step-down circuit, an electromagnetic controller, and a brake shoe. The DC step-down circuit typically employs a buck circuit, the electromagnetic controller typically includes a brake coil, an iron core, and an armature, and the brake shoe typically comprises a brake wheel and brake shoe. The mechanical structure of the brake mechanism is known from the prior art and will not be detailed here. In other structural divisions of related art, the DC step-down circuit is not part of the brake mechanism; that is, the brake mechanism includes the electromagnetic controller and brake shoe. In this case, the DC step-down circuit is spatially isolated from the brake mechanism.

[0048] The brake coil of the electromagnetic controller is electrically connected to the load end of the buck step-down circuit (i.e., the DC step-down circuit). When the brake coil is energized, a magnetic field is generated. Under the action of the magnetic field, the iron core is magnetized and the armature is attracted, thereby separating the brake wheel and brake shoe that were originally engaged together. At this time, the brake mechanism is in the released state; when the brake coil is not energized, no magnetic field is generated around the brake coil, the iron core is not magnetized, and the armature is not attracted, thereby engaging the brake wheel and brake shoe. At this time, the brake mechanism is in the engaged state.

[0049] The brake release process typically includes two phases: initiating release and maintaining release. During the initiating release phase, the brake coil typically draws a high current, while maintaining release requires no high current. Related technologies typically adjust the output voltage of a buck-type step-down (Buck) circuit—that is, the voltage across the brake coil—by adjusting the switching transistor in the circuit. This, in turn, regulates the current in the brake coil. To ensure the stability of the buck-type step-down circuit's output voltage, a sampling circuit or feedback circuit is typically included.

[0050] In related art, the number of electronic components in a brake mechanism is large, resulting in high cost. Furthermore, the greater the number of electronic components, the worse the circuit stability. Therefore, the present application provides a DC step-down circuit that addresses the high cost of brake mechanisms caused by the large number of electronic components in the related art. To further clarify the objectives, technical solutions, and advantages of this application, the following detailed description of the embodiments of this application is provided in conjunction with the accompanying drawings.

[0051] Figure 1 is a schematic diagram of the structure of a brake mechanism provided in an embodiment of the present application. As an example, as shown in Figure 1 , the brake mechanism includes a DC step-down circuit 01 and a brake shoe 02. Brake shoe 02 is conventional and is not described here. In some examples, as shown in Figure 1 , DC step-down circuit 01 includes an input circuit 1, an energy storage inductor 2, and an output circuit 3. Input circuit 1, energy storage inductor 2, and output circuit 3 are electrically connected in sequence.

[0052] Input circuit 1 connects to a power source; energy storage inductor 2 controls the opening and closing of the brake shoe brake through a magnetic field; and output circuit 3 connects to a load. For example, when power is supplied to energy storage inductor 2 via input circuit 1, i.e., current flows through it, it generates a magnetic field that separates the brake wheel and brake shoe of the brake shoe brake, thereby releasing the brake mechanism. When power is not supplied to inductor 2, it generates no magnetic field, causing the brake wheel and brake shoe of the brake shoe brake to engage, thereby engaging the brake mechanism. Output circuit 3 and the load maintain the current in inductor 2.

[0053] As an example, the brake mechanism also includes an armature, which is located within the magnetic field generated by the energy storage inductor 2. There is a certain mechanical connection between the armature and the brake shoe brake 02. The connection structure between the armature and the brake shoe brake 02 will not be described here.

[0054] As an example, the DC step-down circuit 01 may further include a control chip, which is electrically connected to at least the input circuit 1. The control chip is used to control the on / off state of the input circuit 1, thereby controlling the power supply to transmit voltage to the energy storage inductor 2. The connection method between the control chip and the input circuit 1 can adopt the connection method between the control chip and the switching circuit or switching tube in the buck circuit of the related art, so the control chip is not further described here. It should be noted that the control chip can be part of the DC step-down circuit 01, or it can be a part independent of the DC step-down circuit 01, or it can be a control program carried by other control chips. The structural form of the control chip is not limited here.

[0055] In the solution provided in the embodiment of the present application, the DC step-down circuit includes an energy storage inductor 2, which controls the opening and closing of the brake shoe brake through a magnetic field, thereby realizing the switching of the brake mechanism between the release state and the brake state. Using this solution, the energy storage inductor 2 in the DC step-down circuit can replace the brake coil connected to the load end of the DC step-down circuit in the related art. That is, there is no need to set up a brake coil in the brake mechanism. Moreover, the energy storage inductor 2 directly acts on the brake shoe brake. Due to the characteristics of the energy storage inductor 2 itself, there is no need to set up an additional sampling circuit in the DC step-down circuit. Therefore, compared with the brake mechanism in the related art, the brake mechanism using this DC step-down circuit can save at least one brake coil, which is beneficial to reducing the cost of the brake mechanism and improving working stability.

[0056] In some examples, the overall structure of the component can be divided as follows: the energy storage inductor 2 and the brake shoe brake in the DC step-down circuit belong to the same brake mechanism, while the input circuit 1 and the output circuit 3 in the DC step-down circuit do not belong to the brake mechanism. In other words, the energy storage inductor 2 in the DC step-down circuit replaces the brake coil of the electromagnetic controller in the related technology.

[0057] For example, when the energy storage inductor 2 and the brake shoe brake belong to the same brake mechanism, the input circuit 1 and output circuit 3 of the DC step-down circuit are typically located on the same circuit board. This circuit board is spatially isolated from the brake mechanism, that is, there is a certain distance between the circuit board and the brake mechanism or the energy storage inductor 2. The two ends of the energy storage inductor 2 are electrically connected to the circuit board via wires, thereby achieving electrical connection with the input circuit 1 and output circuit 3.

[0058] As an example, a circuit board is provided with a first terminal and a second terminal. The first terminal is electrically connected to input circuit 1, and the second terminal is electrically connected to output circuit 3. The two ends of energy storage inductor 2 are electrically connected to the first terminal and the second terminal, respectively, via wires, thereby achieving circuit connectivity. This solution allows for flexible positioning of the brake mechanism and the circuit board when the brake mechanism is applied to different products. Even if they are remotely located, the circuit board and energy storage inductor 2 can still be electrically connected via wires to form a complete circuit, thus improving overall design flexibility.

[0059] Figure 2 is a structural diagram of a DC step-down circuit provided in an embodiment of the present application. In some examples, as shown in Figure 2, in the DC step-down circuit, the input circuit 1 includes a first switching circuit 11 and a freewheeling circuit 12. The first connection terminal 11a of the first switching circuit 11 is electrically connected to the power supply; the second connection terminal 11b of the first switching circuit 11, the first connection terminal 2a of the energy storage inductor 2 and the output terminal 12b of the freewheeling circuit 12 are electrically connected; the input terminal 12a of the freewheeling circuit 12 is electrically connected to the power supply and the output circuit 3, respectively, wherein the first switching circuit 11 is generally composed of at least one switching tube. The first switching circuit 11 also has a control terminal (not shown in Figure 2), which is electrically connected to the control chip of the above-mentioned DC step-down circuit. The control chip can control the on-off state of the first switching circuit 11, thereby realizing power supply or no power supply to the energy storage inductor.

[0060] FIG3 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application. As an example, as shown in FIG3 , the first switching circuit 11 includes a switching tube, and the number of the switching tube is one. One connection end of the switching tube serves as the first connection end 11a of the first switching circuit 11 and is electrically connected to the power supply. The other connection end of the switching tube serves as the second connection end 11b of the first switching circuit 11 and is electrically connected to the freewheeling circuit 12 and the energy storage inductor 2. The control end of the switching tube is electrically connected to the control chip, and the control chip can control the current flowing through the energy storage inductor 2 by adjusting the duty cycle of the switching tube. Adopting this solution, using one switching tube as the first switching circuit 11 is conducive to simplifying the circuit structure, reducing the number of electronic components in the circuit, and thus helping to save production costs. In addition, the switching tube is simple to control, which is conducive to improving the working efficiency of the circuit.

[0061] The freewheeling circuit 12 may include a switch or a diode. FIG3 illustrates the connection method for the freewheeling circuit 12 using a diode, which will not be described in detail here. When a switch is used, one connection end of the switch serves as the input end 12a of the freewheeling circuit 12, and the other connection end of the switch serves as the output end 12b of the freewheeling circuit 12. The control end of the switch may be electrically connected to a control chip. In this case, the control chip may control the first switch circuit 11 and the freewheeling circuit 12, thereby ensuring the normal operation of the entire DC step-down circuit.

[0062] The structural composition of the first switch circuit 11 and the freewheeling circuit 12 is merely described here for illustrative purposes only and does not impose any limitation thereto.

[0063] FIG4 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application. In some examples, as shown in FIG4 , in the DC step-down circuit, the output circuit 3 includes a filter capacitor 31. The filter capacitor 31 not only plays a filtering role, but also plays a voltage stabilizing role, which is beneficial to improving the stability of the DC step-down circuit. Generally, when selecting the filter capacitor 31, it is necessary to consider the duration required for the above-mentioned start-up and release phases in the brake mechanism. For example, if the start-up and release phases are 200 milliseconds, when selecting the filter capacitor 31, it is necessary to select a capacitor that takes 200 milliseconds to be fully charged, and so on.

[0064] As an example, as shown in FIG4 , the first connection terminal 31 a of the filter capacitor 31 is electrically connected to the second connection terminal 2 b of the energy storage inductor 2 and the load, and the second connection terminal 31 b of the filter capacitor 31 is electrically connected to the input circuit 1 and the load.

[0065] Optionally, the filter capacitor 31 may be a plurality of capacitors connected in series, and the charging time of the plurality of capacitors connected in series needs to meet the time required for the above-mentioned starting and releasing stage.

[0066] FIG5 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application, and FIG6 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application. In other examples, as shown in FIG5 and FIG6, the output circuit 3 may further include a second switch circuit 32, and the second switch circuit 32 is connected in parallel with the above-mentioned filter capacitor 31, wherein the second switch circuit 32 generally includes a switch tube. Specifically, the first connection terminal 32a of the second switch circuit 32 is electrically connected to the first connection terminal 31a of the filter capacitor 31, and the second connection terminal 32b of the second switch circuit 32 is electrically connected to the second connection terminal 31b of the filter capacitor 31. During the above-mentioned startup release phase, the second switch circuit 32 is in a connected state, at which time the filter capacitor 31 is short-circuited, and a large current can continue to flow through the energy storage inductor 2; during the above-mentioned maintenance release phase, the second switch circuit 32 is in a disconnected state, at which time the filter capacitor 31 is in a charging state, and the filter capacitor 31 can play a role in filtering and voltage stabilization.

[0067] As an example, as shown in FIG6 , the second switch circuit 32 is a switch tube, one connection end of which serves as the first connection end 32a of the second switch circuit 32, and the other connection end of which serves as the second connection end 32b of the second switch circuit 32. The control end of the switch tube can be electrically connected to the control chip. When the brake mechanism is in the aforementioned start-up release phase, the control chip can control the switch tube to be in a connected state. At this time, the filter capacitor 31 is short-circuited, allowing a large current to continue to flow through the energy storage inductor 2. When the brake mechanism transitions from the start-up release phase to the maintenance release phase, the control chip can control the switch tube to be in a disconnected state. At this time, the filter capacitor 31 is in an operating state, that is, the filter capacitor 31 is in a charging state. This solution, using a single switch tube as the second switch circuit 32, helps simplify the circuit structure and reduce the number of electronic components in the circuit, thereby saving production costs. Furthermore, the switch tube is simple to control, which helps improve the circuit's operating efficiency.

[0068] With this solution, a second switching circuit 32 is provided in the DC step-down circuit. When the brake mechanism is in the starting release stage, the second switching circuit 32 is connected to allow a larger current to flow through the energy storage inductor 2, thereby generating a stronger magnetic field and causing the brake mechanism to enter the release state. Moreover, the second switching circuit 32 has smaller energy loss, which is beneficial to reducing energy consumption.

[0069] The structural composition of the output circuit 3 and the second switch circuit 32 is merely described here for illustrative purposes only and does not impose any limitation thereto.

[0070] FIG7 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application, and FIG8 is a schematic diagram of the structure of a DC step-down circuit provided in an embodiment of the present application. In some examples, as shown in FIG7 and FIG8 , the load in the DC step-down circuit includes an auxiliary power supply. Typically, an auxiliary power supply is provided in a brake mechanism or a product using a brake mechanism. The auxiliary power supply is used to drive components such as chips in the brake mechanism or the product using the brake mechanism. Typically, the auxiliary power supply needs to be electrically connected to a DC power supply to store electrical energy. With this solution, the load includes an auxiliary power supply. When the DC step-down circuit is used, the auxiliary power supply can be directly charged, which can both simplify the circuit structure and reduce energy consumption.

[0071] As an example, as shown in FIG7 , when the load includes an auxiliary power supply, the DC step-down circuit further includes a third switch circuit 4 and a unidirectional current cutoff circuit 5. A first connection terminal 4a of the third switch circuit 4 is electrically connected to the power supply; an input terminal 5a of the unidirectional current cutoff circuit 5 is electrically connected to a first output terminal 3a of the output circuit 3; a second connection terminal 4b of the third switch circuit 4, an output terminal 5b of the unidirectional current cutoff circuit 5, and a first terminal of the auxiliary power supply are electrically connected; and a second terminal of the auxiliary power supply is electrically connected to a second output terminal 3b of the output circuit 3. The third switch circuit 4 may typically include a switching transistor.

[0072] When the auxiliary power supply needs to be charged or in the above-mentioned starting release stage, the third switch circuit 4 is in a connected state, and the power supply supplies power to the auxiliary power supply through the third switch circuit 4; in the above-mentioned maintaining release stage, the third switch circuit 4 is in a disconnected state, and the unidirectional cut-off circuit 5 is in a connected state, and the power supply supplies power to the auxiliary power supply through the input circuit 1, the energy storage inductor 2, the output circuit 3 and the unidirectional cut-off circuit 5.

[0073] As an example, as shown in Figure 8, the third switching circuit 4 includes a switching transistor, and the unidirectional current-cutoff circuit 5 includes a diode. One connection terminal of the switching transistor serves as the first connection terminal 4a of the third switching circuit 4, and the other connection terminal of the switching transistor serves as the second connection terminal 4b of the third switching circuit 4. The control terminal of the switching transistor can be electrically connected to the aforementioned control chip. When the brake mechanism is in the aforementioned start-up and release phase, the control chip can control the switching transistor to be in a connected state, at which point the power supply charges the auxiliary power supply through the switching transistor. When the brake mechanism transitions from the start-up and release phase to the maintain-release phase, the control chip can control the switching transistor to be in a disconnected state, at which point the unidirectional current-cutoff circuit 5 is in a connected state, thereby supplying power to the auxiliary power supply.

[0074] Optionally, the unidirectional current-cutoff circuit 5 may also include a switching tube, in which case one connection end of the switching tube serves as the input end 5a of the unidirectional current-cutoff circuit 5, and the other connection end of the switching tube serves as the output end 5b of the unidirectional current-cutoff circuit 5. The control end of the switching tube can be electrically connected to the above-mentioned control chip, and the control chip controls the current direction of the switching tube to supply power to the auxiliary power supply.

[0075] In this solution, when a switch tube is used as the third switch circuit 4 and the unidirectional current cutoff circuit 5 respectively, it is beneficial to simplify the circuit structure and reduce the number of electronic components in the circuit, thereby saving production costs. In addition, the switch tube is simple to control, which is beneficial to improving the working efficiency of the circuit.

[0076] Optionally, the load may include only a resistor, or an auxiliary power supply and a resistor connected in parallel, etc. The specific composition of the load, the structural composition of the third switch circuit 4, and the structural composition of the unidirectional current cutoff circuit 5 are merely illustrative and do not limit them in any way.

[0077] Based on the same technical concept, the embodiments of the present application also provide a brake mechanism. As an example, as shown in Figure 1, the brake mechanism includes any of the DC step-down circuits 01 and brake shoe brake 02 provided in the embodiments of the present application. Using this solution, the energy storage inductor 2 in the DC step-down circuit can replace the brake coil connected to the load end of the DC step-down circuit in the related art. That is, there is no need to provide a brake coil in the brake mechanism. Moreover, the energy storage inductor 2 directly acts on the brake shoe brake. Due to the characteristics of the energy storage inductor 2 itself, there is no need to provide an additional sampling circuit in the DC step-down circuit. Therefore, compared to the brake mechanism in the related art, the brake mechanism using this DC step-down circuit can save at least one brake coil, thereby reducing the cost of the brake mechanism and improving its operating stability.

[0078] In some examples, the armature of the brake mechanism is located within the magnetic field generated by the energy storage inductor 2 of the DC step-down circuit 01. When current flows through the energy storage inductor 2, a magnetic field is generated, which attracts the armature of the brake mechanism, thereby separating the brake wheel and brake shoe in the engaged state and releasing the brake.

[0079] In some examples, the brake mechanism also includes an iron core wound around an energy storage inductor 2. When energized, the energy storage inductor 2 generates a magnetic field. Under the influence of this magnetic field, the iron core magnetizes and attracts the armature, thereby separating the previously engaged brake wheel and brake shoe. In this state, the brake mechanism is in the released state. When the energy storage inductor 2 is de-energized, no magnetic field is generated around it, and the iron core remains unmagnetized, preventing the armature from being attracted. As a result, the brake wheel and brake shoe are engaged, and the brake mechanism is in the engaged state. This solution magnetizes the iron core in response to the magnetic field generated by the energy storage inductor 2, enhancing the attraction of the armature. This, in turn, reduces the time required to initiate brake release, thereby improving operating efficiency.

[0080] Based on the same technical concept, an embodiment of the present application also provides a motor, which includes any one of the brake mechanisms provided in the embodiments of the present application. The motor can be used in, but is not limited to, scenarios such as elevators, access control, and AGVs (Automated Guided Vehicles). Using this solution, the energy storage inductor 2 in the DC step-down circuit can replace the brake coil connected to the load end of the DC step-down circuit in the related art. That is, there is no need to set up a brake coil in the brake mechanism. Moreover, the energy storage inductor 2 directly acts on the brake shoe. Due to the characteristics of the energy storage inductor 2 itself, there is no need to set up an additional sampling circuit in the DC step-down circuit. Therefore, the brake mechanism using this DC step-down circuit can save at least one brake coil compared to the brake mechanism in the related art, which is beneficial to reducing the cost of the brake mechanism and the motor, and is beneficial to improving working stability.

[0081] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A DC step-down circuit, characterized in that: The DC step-down circuit comprises an input circuit (1), an energy storage inductor (2) and an output circuit (3), wherein the input circuit (1), the energy storage inductor (2) and the output circuit (3) are electrically connected in sequence; The input circuit (1) is used to connect to a power source; The energy storage inductor (2) is used to control the opening and closing of the brake shoe brake through a magnetic field; The output circuit (3) is used for connecting to a load.

2. The DC step-down circuit according to claim 1, characterized in that: The energy storage inductor (2) and the brake shoe brake belong to the same brake mechanism.

3. The DC step-down circuit according to claim 2, characterized in that: The input circuit (1) and the output circuit (3) are located on the same circuit board, the circuit board is spatially isolated from the brake mechanism, and the two ends of the energy storage inductor (2) are electrically connected to the input circuit (1) and the output circuit (3) respectively through wires.

4. The DC step-down circuit according to any one of claims 1 to 3, characterized in that: The input circuit (1) comprises a first switch circuit (11) and a freewheeling circuit (12); The first connection end (11a) of the first switch circuit (11) is electrically connected to the power supply; The second connection end (11b) of the first switch circuit (11), the first connection end (2a) of the energy storage inductor (2), and the output end (12b) of the freewheeling circuit (12) are electrically connected; The input end (12a) of the freewheeling circuit (12) is electrically connected to the power supply and the output circuit (3) respectively.

5. The DC step-down circuit according to any one of claims 1 to 3, characterized in that: The output circuit (3) comprises a filter capacitor (31); The first connection end (31a) of the filter capacitor (31) is electrically connected to the second connection end (2b) of the energy storage inductor (2) and the load, respectively, and the second connection end (31b) of the filter capacitor (31) is electrically connected to the input circuit (1) and the load, respectively.

6. The DC step-down circuit according to claim 5, characterized in that: The output circuit (3) further includes a second switch circuit (32); The first connection end (32a) of the second switch circuit (32) is electrically connected to the first connection end (31a) of the filter capacitor (31), and the second connection end (32b) of the second switch circuit (32) is electrically connected to the second connection end (31b) of the filter capacitor (31).

7. The DC step-down circuit according to any one of claims 1 to 3, characterized in that: The load includes an auxiliary power supply.

8. The DC step-down circuit according to claim 7, characterized in that: The DC step-down circuit also includes a third switch circuit (4) and a unidirectional current cutoff circuit (5); The first connection end (4a) of the third switch circuit (4) is electrically connected to the power supply; The input end (5a) of the unidirectional current cutoff circuit (5) is electrically connected to the first output end (3a) of the output circuit (3); The second connection end (4b) of the third switch circuit (4), the output end (5b) of the unidirectional current cutoff circuit (5) and the first end of the auxiliary power supply are electrically connected; The second end of the auxiliary power supply is electrically connected to the second output end (3b) of the output circuit (3).

9. A brake mechanism, characterized in that: The holding brake mechanism comprises a DC step-down circuit (01) and a brake shoe brake (02) as claimed in any one of claims 1 to 8.

10. The brake mechanism according to claim 9, characterized in that: The armature of the brake mechanism is located within the magnetic field range generated by the energy storage inductor (2) of the DC step-down circuit (01).

11. The brake mechanism according to claim 9 or 10, characterized in that: The holding brake mechanism also includes an iron core, and the iron core is wound around the energy storage inductor (2).

12. A motor, characterized in that: The motor comprises a brake mechanism as described in any one of claims 9 to 11.

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