Motor overcurrent protection circuit and massage device
By introducing a protection delay unit into the motor overcurrent protection circuit, the motor control unit is controlled to disconnect within a preset delay time, which solves the problem of frequent switching of the switching transistor in the traditional motor overcurrent protection circuit and improves the effect of motor overcurrent protection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN BREO TECH CO LTD
- Filing Date
- 2025-06-11
- Publication Date
- 2026-06-19
AI Technical Summary
Traditional motor overcurrent protection circuits suffer from poor overcurrent protection because the transistors turn on and off instantaneously during overcurrent, resulting in frequent switching of the switching transistors and the motor overcurrent protection effect being ineffective.
A protection delay unit is used to control the motor control unit to disconnect within a preset delay time, avoiding frequent switching of the switching transistor. Through the design of the protection delay unit, when the motor drive unit experiences overcurrent, the motor control unit is controlled to remain in the disconnected state within the preset delay time.
It improves the overcurrent protection effect of the motor, avoids damage caused by frequent switching of the switching transistor, and extends the service life of the motor.
Smart Images
Figure CN224385066U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of overcurrent protection technology, and in particular to an overcurrent protection circuit for a motor and a massage device. Background Technology
[0002] As motors are used more and more widely in various fields, users are also putting forward higher requirements for motor overcurrent protection.
[0003] Traditional motor overcurrent protection circuits achieve overcurrent protection by directly turning on a transistor during an overcurrent event, grounding the control terminal of the switching transistor (in the motor control unit) that controls the motor's operation (at which point the control terminal of the switching transistor is grounded, and the motor shuts off). However, this type of overcurrent protection circuit has a significant drawback: because the transistor only turns on momentarily during an overcurrent event to shut down the motor (and then immediately turns off again, leaving the control terminal of the switching transistor ungrounded and allowing the motor to continue operating), the switching transistor frequently turns on and off. This frequent switching (which can damage the switching transistor) ultimately results in ineffective overcurrent protection.
[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Utility Model Content
[0005] The main purpose of this application is to provide a motor overcurrent protection circuit and a massage device, which aims to solve the technical problem of poor motor overcurrent protection performance.
[0006] To achieve the above objectives, this application provides a motor overcurrent protection circuit, the motor overcurrent protection circuit comprising:
[0007] A motor drive unit, wherein the first end of the motor drive unit is connected to a power supply;
[0008] A motor control unit, wherein a first terminal of the motor control unit is connected to an external controller, and a second terminal of the motor control unit is connected to a second terminal of the motor drive unit;
[0009] A protection delay unit is provided, wherein a first end of the protection delay unit is connected to a second end of the motor control unit and a second end of the motor drive unit, a second end of the protection delay unit is connected to a first end of the motor control unit, and a third end of the protection delay unit is connected to a third end of the motor control unit. When the motor drive unit experiences an overcurrent, the protection delay unit controls the motor control unit to be in a disconnected state for a preset delay time to achieve overcurrent protection.
[0010] In one embodiment, the motor control unit includes:
[0011] A switching transistor, wherein the first end of the switching transistor serves as the second end of the motor control unit and is connected to the second end of the motor drive unit; the second end of the switching transistor serves as the third end of the motor control unit and is connected to the third end of the protection delay unit; and the third end of the switching transistor serves as the first end of the motor control unit and is connected to the external controller and the second end of the protection delay unit.
[0012] In one embodiment, the switching transistor includes one of a MOS transistor and an ICBT transistor, wherein the third terminal of the switching transistor is the gate of the switching transistor, the first terminal of the switching transistor is the drain of the switching transistor, and the second terminal of the switching transistor is the source of the switching transistor.
[0013] In one embodiment, the protection delay unit includes:
[0014] A capacitor subunit, wherein the first end of the capacitor subunit serves as the first end of the protection delay unit and is connected to the first end of the switching transistor in the motor control unit and the second end of the motor drive unit;
[0015] The first diode has its anode serving as the third terminal of the protection delay unit and connected to the second terminal of the switching transistor, while its cathode is connected to the second terminal of the capacitor subunit.
[0016] A first resistor, the first end of which is connected to the cathode of the first diode and the second end of the capacitor subunit;
[0017] The transistor has its first terminal connected to the second terminal of the first resistor, and its second terminal serves as the second terminal of the protection delay unit. It is also connected to the third terminal of the switching transistor, and the third terminal of the transistor is grounded.
[0018] In one embodiment, the first terminal of the transistor is the base of the transistor, the second terminal of the transistor is the collector of the transistor, and the third terminal of the transistor is the emitter of the transistor.
[0019] In one embodiment, the protection delay unit further includes:
[0020] The second capacitor has its first terminal connected to the anode of the first diode and the second terminal of the switching transistor, and its second terminal connected to the first terminal of the transistor and the second terminal of the first resistor.
[0021] In one embodiment, the motor overcurrent protection circuit further includes:
[0022] The second resistor has its first end connected to the external controller and its second end connected to the second end of the transistor and the third end of the switching transistor.
[0023] The third resistor has its first end connected to the anode of the first diode and the second end of the switching transistor, and its second end grounded.
[0024] In one embodiment, the capacitor subunit includes:
[0025] Multiple first capacitors with different capacitance values are connected together at their first terminals to form the first terminal of the capacitor subunit.
[0026] The selection device has one input terminal connected to the second terminal of the first capacitor, the output terminal of the selection device serving as the second terminal of the capacitor subunit, and the control terminal of the selection device connected to an external input device.
[0027] In one embodiment, the motor drive unit includes:
[0028] The second diode has its anode serving as the second terminal of the motor drive unit and connected to the first terminal of the switching transistor in the motor control unit and the first terminal of the first capacitor in the protection delay unit. The cathode of the second diode serves as the first terminal of the motor drive unit and is connected to the power supply.
[0029] The motor has a first end that is connected to the cathode of the second diode and serves as the first end of the motor drive unit, and a second end that is connected to the anode of the second diode and serves as the second end of the motor drive unit.
[0030] In addition, to achieve the above objectives, a massage device is also provided, wherein the massage device has the above-mentioned motor overcurrent protection circuit.
[0031] This application provides a motor overcurrent protection circuit, including a motor drive unit, a first terminal of which is connected to a power supply; a motor control unit, a first terminal of which is connected to an external controller, and a second terminal of which is connected to a second terminal of the motor drive unit; and a protection delay unit, a first terminal of which is connected to both the second terminal of the motor control unit and the second terminal of the motor drive unit, a second terminal of which is connected to both the first terminal of the motor control unit and the first terminal of the motor drive unit, and a third terminal of which is connected to both the third terminal of the motor control unit. When the motor drive unit experiences an overcurrent, the protection delay unit controls the motor control unit to remain in an open state for a preset delay time to achieve overcurrent protection. This motor overcurrent protection circuit achieves this by connecting the first terminal of the protection delay unit to both the second terminal of the motor control unit and the second terminal of the motor drive unit, and the second terminal of the protection delay unit to... The first terminal of the motor control unit is connected, and the third terminal of the protection delay unit is connected to the third terminal of the motor control unit. When the motor drive unit experiences overcurrent (mainly overcurrent in the motor itself), the motor control unit is controlled to remain in a disconnected state for a preset delay time (the disconnected state means the motor is not powered), thus achieving overcurrent protection. This avoids the frequent switching of the switching transistor in the motor control unit, which occurs because the transistor only turns on momentarily during overcurrent to shut down the motor (and then immediately turns off again, causing the control terminal of the switching transistor to be ungrounded and the motor to continue running). This motor overcurrent protection circuit, when the motor in the motor drive unit experiences overcurrent, controls the motor control unit to remain in a disconnected state for a preset delay time through the protection delay unit, thereby avoiding the impact of frequent switching of the switching transistor in the motor control unit and improving the effectiveness of motor overcurrent protection. Attached Figure Description
[0032] Figure 1 This is a schematic diagram of the framework of the first embodiment of the motor overcurrent protection circuit of this application;
[0033] Figure 2 This is a connection diagram of an existing motor overcurrent protection circuit.
[0034] Figure 3 This is a connection diagram of the motor control unit in the motor overcurrent protection circuit of this application;
[0035] Figure 4 This is a connection diagram of the protection delay unit in the motor overcurrent protection circuit of this application;
[0036] Figure 5 This is a connection diagram of the motor overcurrent protection circuit of this application;
[0037] Figure 6 This is another connection diagram of the motor overcurrent protection circuit of this application.
[0038] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.
[0039] Explanation of icon numbers:
[0040] 200, External controller; 10, Motor drive unit; 20, Motor control unit; 30, Protection delay unit; VDD, Power supply; R1, First resistor; R2, Second resistor; R3, Third resistor; Q1, Transistor; G1, Switching transistor; 11, Motor; D1, First diode; D2, Second diode; 31, Capacitor subunit; 3A, Selector device; 300, External input device; C1, First capacitor; C2, Second capacitor. Detailed Implementation
[0041] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.
[0042] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.
[0043] In any scenario involving the use of motors, the phenomenon of motor overcurrent will occur. Taking massage devices as an example, most massagers contain motors. Under abnormal force, the motor may stall, causing it to overheat and even damaging the power components driving the motor. (See also...) Figure 2 , Figure 2 This is a schematic diagram of a current motor overcurrent protection circuit. During normal operation, the GPIO (General Purpose Input / Output) in the external controller 200 is high, the switching transistor G1 is turned on, and the motor 11 starts working. When the motor 11 stalls, the current through the third resistor R3 increases sharply, the transistor Q1 turns on, the gate (G) of the switching transistor G1 goes low, the switching transistor G1 turns off, and the motor 11 stops working. However, the GPIO remains high, and the gate voltage of the switching transistor G1 gradually rises until Vgs reaches its turn-on voltage. The switching transistor G1 first enters the linear operating region and then the saturation region. The stalled state of the motor 11 is not resolved in time, the current through the third resistor R3 increases, the transistor Q1 turns on, and the above cycle repeats. Consequently, the switching transistor G1 frequently enters the linear operating region, causing it to overheat and eventually be damaged. This results in poor overcurrent protection for the motor.
[0044] Therefore, based on the shortcomings of the above-mentioned motor overcurrent protection methods, the motor overcurrent protection circuit of this application is proposed: the first terminal of the protection delay unit 30 is connected to the second terminal of the motor control unit 20 and the second terminal of the motor drive unit 10, the second terminal of the protection delay unit 30 is connected to the first terminal of the motor control unit 20, and the third terminal of the protection delay unit 30 is connected to the third terminal of the motor control unit 20. Thus, when the motor drive unit 10 experiences an overcurrent (mainly when the motor 11 in the motor drive unit 10 experiences an overcurrent), the motor control unit 20 is controlled to be in an off state for a preset delay time (the off state means that the motor 11 is not powered). This overcurrent protection circuit avoids the frequent switching of the switching transistor G1 in the motor control unit 20, which occurs because transistor Q1 only turns on momentarily during an overcurrent event to shut down motor 11 (and then immediately turns off again, causing the control terminal of the switching transistor G1 to be ungrounded and continue to turn on motor 11). When motor 11 in the motor drive unit 10 experiences an overcurrent, the protection delay unit 30 controls the motor control unit 20 to remain in an open state for a preset delay time, thus avoiding the impact of frequent switching of the switching transistor G1 in the motor control unit 20 and improving the effectiveness of motor overcurrent protection.
[0045] Based on this, the embodiments of this application provide a motor overcurrent protection circuit, referring to... Figure 1 , Figure 1 This is a schematic diagram of the framework of the first embodiment of the motor overcurrent protection circuit of this application.
[0046] Reference Figure 1 This application provides a motor overcurrent protection circuit, which includes:
[0047] Motor drive unit 10, the first end of motor drive unit 10 is connected to power supply VDD;
[0048] The motor control unit 20 has a first end connected to the external controller 200 and a second end connected to the second end of the motor drive unit 10.
[0049] The protection delay unit 30 has its first end connected to the second end of the motor control unit 20 and the second end of the motor drive unit 10, its second end connected to the first end of the motor control unit 20, and its third end connected to the third end of the motor control unit 20. When the motor drive unit 10 experiences an overcurrent, the protection delay unit 30 controls the motor control unit 20 to be in an open state for a preset delay time to achieve overcurrent protection.
[0050] In this embodiment, the first terminal of the motor drive unit 10 is connected to the power supply VDD, and the first terminal of the motor control unit 20 is connected to the external controller 200. The second terminal of the motor control unit 20 is connected to the second terminal of the motor drive unit 10. When the motor 11 is working normally, the external controller 200 outputs a high level (assuming that the high level controls the motor 11 in the motor drive unit 10 to start working). The external controller 200 can be a single controller, such as a microcontroller, directly outputting high and low levels; or it can be a combination of a power supply and a switch. When the motor 11 needs to work, the first terminal of the motor control unit 20 is connected to the power supply, thereby outputting a high level to the motor control unit 20, so that the motor 11 forms a power supply circuit, thereby driving the motor 11 in the motor drive unit 10 to work normally. Conversely, the connection to the power supply is disconnected, so that the power supply circuit of the motor 11 is broken, thereby stopping the motor 11 in the motor drive unit 10 from working. It is worth noting that forming a power supply circuit for the motor 11 means that the power supply VDD - motor 11 - motor control unit 20 - ground form a loop, that is, the third terminal of the motor control unit 20 is grounded. When an overcurrent occurs due to a stall in the motor 11 of the motor drive unit 10, the protection delay unit 30 is used to provide overcurrent protection for the entire control circuit of the motor 11. Specifically, when an overcurrent occurs in the motor drive unit 10 (manifested as a significant change in the current flowing through the motor control unit 20 compared to normal conditions, such as a change from the range AB to a value above B), the motor control unit 20 is kept in a disconnected state for a preset delay time. This prevents the motor control unit 20 from intermittently switching on and off the power supply circuit to the motor 11, which could damage the motor control unit 20. The protection delay unit 30 controls the motor control unit 20 to remain disconnected for the preset delay time, avoiding the effects of frequent switching of the switching transistor G1 in the motor control unit 20, thus improving the effectiveness of the motor overcurrent protection.
[0051] In one embodiment, the protection delay unit 30 can be directly designed as a controller. The controller works by detecting an overcurrent in the motor drive unit 10 and then controlling the external controller 200 to output a high level after a certain period of time. This delays the disconnection of the switching transistor G1 in the motor control unit 20, thereby improving the overcurrent protection effect of the motor by protecting the switching transistor G1 in the motor control unit 20. It is worth noting that the protection delay unit 30 can also be a circuit. This circuit works by detecting an overcurrent in the motor drive unit 10 and then continuously controlling the motor control unit 20 to be in an off state for a certain period of time to ensure protection of the motor control unit 20. Other design methods are also possible and are not limited here.
[0052] In this embodiment, a motor overcurrent protection circuit is provided, including a motor drive unit 10, the first terminal of which is connected to a power supply VDD; a motor control unit 20, the first terminal of which is connected to an external controller 200, and the second terminal of which is connected to the second terminal of the motor drive unit 10; and a protection delay unit 30, the first terminal of which is connected to both the second terminal of the motor control unit 20 and the second terminal of the motor drive unit 10, the second terminal of which is connected to both the first terminal of the motor control unit 20 and the first terminal of the motor drive unit 10, and the third terminal of which is connected to both the third terminal of the motor control unit 20. When the motor drive unit 10 experiences an overcurrent, the protection delay unit 30 controls the motor control unit 20 to be in an open state for a preset delay time to achieve overcurrent protection. This motor overcurrent protection circuit achieves overcurrent protection by connecting the first terminal of the protection delay unit 30 to the second terminal of the motor control unit 20 and the second terminal of the motor drive unit 10. The second terminal of the protection delay unit 30 is connected to the first terminal of the motor control unit 20, and the third terminal of the protection delay unit 30 is connected to the third terminal of the motor control unit 20. Therefore, when the motor drive unit 10 experiences overcurrent (mainly when the motor 11 in the motor drive unit 10 experiences overcurrent), the motor control unit 20 is controlled to be in a disconnected state for a preset delay time (the disconnected state means that the motor 11 is not powered), thus achieving overcurrent protection. This avoids the phenomenon of the switching transistor G1 in the motor control unit 20 frequently turning on and off because the transistor Q1 only turns on momentarily during overcurrent to shut down the motor 11 (and then immediately turns off again, causing the control terminal of the switching transistor G1 to be ungrounded and continue to turn on the motor 11). This motor overcurrent protection circuit, when the motor 11 in the motor drive unit 10 experiences overcurrent, controls the motor control unit 20 to be in a disconnected state for a preset delay time through the protection delay unit 30, thereby avoiding the impact of the frequent turning on and off of the switching transistor G1 in the motor control unit 20 and improving the effectiveness of motor overcurrent protection.
[0053] Furthermore, based on the first embodiment of this application described above, a second embodiment of the motor overcurrent protection circuit of this application is proposed, referring to... Figure 3 , Figure 3 This is a connection diagram of the motor control unit in the motor overcurrent protection circuit of this application. The motor control unit 20 includes:
[0054] The first end of the switching transistor G1 serves as the second end of the motor control unit 20 and is connected to the second end of the motor drive unit 10. The second end of the switching transistor G1 serves as the third end of the motor control unit 20 and is connected to the third end of the protection delay unit 30. The third end of the switching transistor G1 serves as the first end of the motor control unit 20 and is connected to the second end of the external controller 200 and the protection delay unit 30.
[0055] Furthermore, the switching transistor G1 includes either a MOS (Metal-Oxide-Semiconductor) transistor or an ICBT (Insulated Gate Bipolar Transistor) transistor, wherein the third terminal of the switching transistor G1 is the gate of the switching transistor G1, the first terminal of the switching transistor G1 is the drain of the switching transistor G1, and the second terminal of the switching transistor G1 is the source of the switching transistor G1.
[0056] In this embodiment, the motor control unit 20 includes a switching transistor G1, which controls the switching on and off of the motor 11 to achieve operation and overcurrent protection. The control of the switching transistor G1 is primarily based on the output level of the external controller 200, using the output of the external controller 200 to control the conduction and cutoff of the switching transistor G1, thereby enabling the switching on and off of the power supply circuit for the motor 11. The switching transistor G1 can be either a MOSFET or an ICP-T transistor, as described in [reference needed]. Figure 3 The switching transistor G1 can be an N-type switching transistor. In this case, the third terminal of the switching transistor G1 is the gate of the switching transistor G1, the first terminal of the switching transistor G1 is the drain of the switching transistor G1, and the second terminal of the switching transistor G1 is the source of the switching transistor G1. Of course, a P-type switching transistor or other switching devices can also be used according to other logic, which is not limited here.
[0057] In one embodiment, reference is made to Figure 4 , Figure 4 This is a connection diagram of a protection delay unit in the motor overcurrent protection circuit of this application. The protection delay unit 30 includes:
[0058] Capacitor subunit 31, the first end of capacitor subunit 31 serves as the first end of protection delay unit 30, and is connected to the first end of switch transistor G1 in motor control unit 20 and the second end of motor drive unit 10.
[0059] The anode of the first diode D1 serves as the third terminal of the protection delay unit 30 and is connected to the second terminal of the switching transistor G1. The cathode of the first diode D1 is connected to the second terminal of the capacitor subunit 31.
[0060] The first resistor R1 has its first end connected to the cathode of the first diode D1 and the second end of the capacitor subunit 31.
[0061] Transistor Q1 has its first terminal connected to the second terminal of the first resistor R1. The second terminal of transistor Q1 serves as the second terminal of the protection delay unit 30 and is connected to the third terminal of the switching transistor G1. The third terminal of transistor Q1 is grounded.
[0062] Furthermore, the first terminal of transistor Q1 is the base of transistor Q1, the second terminal of transistor Q1 is the collector of transistor Q1, and the third terminal of transistor Q1 is the emitter of transistor Q1.
[0063] Furthermore, the capacitor subunit 31 includes:
[0064] Multiple first capacitors C1 with different capacitance values are connected together at their first ends to form the first end of capacitor subunit 31.
[0065] Select device 3A, one input terminal of select device 3A is connected to the second terminal of a first capacitor C1, the output terminal of select device 3A is used as the second terminal of capacitor subunit 31, and the control terminal of select device 3A is connected to external input device 300.
[0066] In this embodiment, the protection delay unit 30 can be composed of a capacitor subunit 31, a first diode D1, a first resistor R1, and a first diode D1. The capacitor subunit 31 includes multiple first capacitors C1 with different capacitance values, and a selection device 3A. The selection device 3A can be controlled by an external input device 300 to select which first capacitor C1 to use in the circuit. Taking the presence of two first capacitors C1 as an example, the selection device 3A can include a 2-to-1 selector. The external input device 300 can be a level input device that can input a high or low level to the 2-to-1 selector. When the 2-to-1 selector receives a high level, it selects the first first capacitor C1 to use in the circuit; conversely, when it receives a low level, it selects the second first capacitor C1 to use in the circuit. This control enables the selection of different first capacitors C1. Meanwhile, transistor Q1 is designed as a P-type transistor. The first terminal of transistor Q1 is the base of transistor Q1, the second terminal of transistor Q1 is the collector of transistor Q1, and the third terminal of transistor Q1 is the emitter of transistor Q1. Of course, P-type switching transistors or other switching devices can also be used according to other logic, which is not limited here.
[0067] In one embodiment, it is assumed that the user has already selected the first capacitor C1 to be used, such as Figure 4As shown, when the GPIO in the external controller 200 is high, the switching transistor G1 is turned on, and the motor 11 starts working. When the motor 11 stalls, the current through the third resistor R3 increases sharply, the transistor Q1 turns on, the switching transistor G1 turns off, and the motor 11 stops working. Because the voltage across the first capacitor C1 cannot change abruptly, the base and emitter terminals of the transistor Q1 are charged through the first resistor R1, thus keeping the transistor Q1 on and keeping the switching transistor G1 off (i.e., the switching transistor G1 will remain off for a period of time, and the motor 11 will not work). When the first capacitor C1 is fully charged, the first capacitor C1 is equivalent to an open circuit. At this time, the transistor Q1 turns off, the switching transistor G1 turns on again, and the motor works normally. That is, different first capacitors C1 can be selected to achieve different delay times, thereby ensuring that the stall time of the motor 11 is staggered. Simultaneously, the first capacitor C1 discharges through the drain and source terminals of the switching transistor G1 and the first diode D1, awaiting the next overcurrent protection event. This delays the turn-off of the switching transistor G1 by using the first capacitor C1. At this time, the first diode D1 ensures that the first capacitor C1 can only be charged through the first resistor R1 and the base-emitter junction of the transistor Q1, while also providing a discharge path for the first capacitor C1 (preventing reverse current flow). Positive feedback can be introduced through the first capacitor C1, extending the turn-off time of the transistor Q1, preventing the switching transistor G1 from frequently entering the linear operating region, reducing its switching losses, and thus protecting the switching transistor G1. This improves the effectiveness of motor overcurrent protection through the protection device.
[0068] In one embodiment, the protection delay unit 30 further includes:
[0069] The second capacitor C2 has its first terminal connected to the anode of the first diode D1 and the second terminal of the switching transistor G1, and its second terminal connected to the first terminal of the transistor Q1 and the second terminal of the first resistor R1.
[0070] In this embodiment, the protection delay unit 30 further includes a second capacitor C2. The first end of the second capacitor C2 is connected to the anode of the first diode D1 and the second end of the switching transistor G1, and the second end of the second capacitor C2 is connected to the first end of the transistor Q1 and the second end of the first resistor R1. That is, when the motor 11 stalls, the current will rise rapidly. The function of the second capacitor C2 is to enable the switching transistor Q1 to quickly sense the change in the output current of the switching transistor G1 (i.e., through the third resistor R3), which can accelerate the conduction of the transistor Q1. In this way, the overcurrent protection control efficiency can be ensured by quickly responding to the overcurrent state of the motor 11.
[0071] Furthermore, based on the first and / or second embodiments of this application described above, a third embodiment of the motor overcurrent protection circuit of this application is proposed, referring to... Figure 5 , Figure 5 This is a connection diagram of the motor overcurrent protection circuit of this application. The motor overcurrent protection circuit also includes:
[0072] The second resistor R2 has its first end connected to the external controller 200, and its second end connected to the second end of transistor Q1 and the third end of switching transistor G1.
[0073] The third resistor R3 has its first end connected to the anode of the first diode D1 and the second end of the switching transistor G1, and its second end grounded.
[0074] In one embodiment, refer to Figure 6 , Figure 6 This is another connection diagram of the motor overcurrent protection circuit of this application. The motor drive unit 10 includes:
[0075] The anode of the second diode D2 serves as the second terminal of the motor drive unit 10 and is connected to the first terminal of the switching transistor G1 in the motor control unit 20 and the first terminal of the first capacitor C1 in the protection delay unit 30. The cathode of the second diode D2 serves as the first terminal of the motor drive unit 10 and is connected to the power supply VDD.
[0076] Motor 11, the first end of motor 11 is connected to the cathode of the second diode D2 and serves as the first end of motor drive unit 10, and the second end of motor 11 is connected to the anode of the second diode D2 and serves as the second end of motor drive unit 10.
[0077] In this embodiment, the motor overcurrent protection circuit further includes: a second resistor R2, the first end of which is connected to the external controller 200, and the second end of which is connected to the second end of the transistor Q1 and the third end of the switching transistor G1; and a third resistor R3, the first end of which is connected to the anode of the first diode D1 and the second end of the switching transistor G1, and the second end of which is grounded. That is, a resistor is used to isolate the grounding and the control point to ensure the safety of the entire circuit. Meanwhile, the motor drive unit 10 includes a motor 11 and a second diode D2. The second diode D2 can be used to prevent current backflow or for other purposes. The motor 11 may include a DC motor. When the motor 11 stalls, an overcurrent phenomenon will occur, that is, the current through the third resistor R3 will increase, which will cause the base voltage of the transistor Q1 to increase to reach the conduction voltage of the transistor Q1, thereby controlling the transistor Q1 to conduct, so that the gate of the switching transistor G1 is grounded, causing the switching transistor G1 to turn off. Then, based on the protection delay unit in the above embodiment, the transistor Q1 will remain in the conducting state for a period of time, while the gate of the switching transistor G1 will be grounded, forming the state of the switching transistor G1 being off. This can prevent the switching transistor G1 from repeatedly cycling between on and off, and protect the switching transistor G1 based on the continuous off of the switching transistor G1 for a period of time, thereby ensuring the effect of motor overcurrent protection.
[0078] Based on the first, second, and / or third embodiments of the motor overcurrent protection circuit, this application also provides a massage device, which includes the above-described motor overcurrent protection circuit.
[0079] It is worth noting that, according to the massage device of this utility model embodiment, the massage device connects the first end of the protection delay unit to the second end of the motor control unit and the second end of the motor drive unit, the second end of the protection delay unit to the first end of the motor control unit, and the third end of the protection delay unit to the third end of the motor control unit. Thus, when the motor drive unit experiences overcurrent (mainly when the motor itself is overcurrent), the motor control unit is controlled to be in a disconnected state for a preset delay time (the disconnected state means the motor is not powered), thereby achieving overcurrent protection. This avoids the phenomenon of frequent switching of the switching transistor in the motor control unit due to the transistor only turning on at the moment of overcurrent to shut down the motor (and then immediately turning off again, causing the control terminal of the switching transistor to be ungrounded and the motor to continue running). This motor overcurrent protection circuit, when the motor in the motor drive unit experiences overcurrent, controls the motor control unit to be in a disconnected state for a preset delay time through the protection delay unit, thus avoiding the impact of frequent switching of the switching transistor in the motor control unit and improving the effectiveness of motor overcurrent protection.
[0080] The massage device (or other device) provided in this application offers a novel motor overcurrent protection circuit to ensure effective motor overcurrent protection. Compared to the prior art, the beneficial effects of the device provided in this application are the same as those of the motor overcurrent protection circuit provided in the above embodiments, and will not be elaborated upon here.
[0081] The above are only some embodiments of this application and do not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the content of this application specification and drawings, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.
Claims
1. A motor overcurrent protection circuit, characterized in that, The motor overcurrent protection circuit includes: A motor drive unit, wherein the first end of the motor drive unit is connected to a power supply; A motor control unit, wherein a first terminal of the motor control unit is connected to an external controller, and a second terminal of the motor control unit is connected to a second terminal of the motor drive unit; A protection delay unit is provided, wherein a first end of the protection delay unit is connected to a second end of the motor control unit and a second end of the motor drive unit, a second end of the protection delay unit is connected to a first end of the motor control unit, and a third end of the protection delay unit is connected to a third end of the motor control unit. When the motor drive unit experiences an overcurrent, the protection delay unit controls the motor control unit to be in a disconnected state for a preset delay time to achieve overcurrent protection.
2. The motor overcurrent protection circuit as described in claim 1, characterized in that, The motor control unit includes: A switching transistor, wherein the first end of the switching transistor serves as the second end of the motor control unit and is connected to the second end of the motor drive unit; the second end of the switching transistor serves as the third end of the motor control unit and is connected to the third end of the protection delay unit; and the third end of the switching transistor serves as the first end of the motor control unit and is connected to the external controller and the second end of the protection delay unit.
3. The motor overcurrent protection circuit as described in claim 2, characterized in that, The switching transistor includes one of a MOS transistor and an ICBT transistor, wherein the third terminal of the switching transistor is the gate of the switching transistor, the first terminal of the switching transistor is the drain of the switching transistor, and the second terminal of the switching transistor is the source of the switching transistor.
4. The motor overcurrent protection circuit as described in claim 1, characterized in that, The protection delay unit includes: A capacitor subunit, wherein the first end of the capacitor subunit serves as the first end of the protection delay unit and is connected to the first end of the switching transistor in the motor control unit and the second end of the motor drive unit; The first diode has its anode serving as the third terminal of the protection delay unit and connected to the second terminal of the switching transistor, while its cathode is connected to the second terminal of the capacitor subunit. A first resistor, the first end of which is connected to the cathode of the first diode and the second end of the capacitor subunit; The transistor has its first terminal connected to the second terminal of the first resistor, and its second terminal serves as the second terminal of the protection delay unit. It is also connected to the third terminal of the switching transistor, and the third terminal of the transistor is grounded.
5. The motor overcurrent protection circuit as described in claim 4, characterized in that, The first terminal of the transistor is the base of the transistor, the second terminal of the transistor is the collector of the transistor, and the third terminal of the transistor is the emitter of the transistor.
6. The motor overcurrent protection circuit as described in claim 4, characterized in that, The protection delay unit further includes: The second capacitor has its first terminal connected to the anode of the first diode and the second terminal of the switching transistor, and its second terminal connected to the first terminal of the transistor and the second terminal of the first resistor.
7. The motor overcurrent protection circuit as described in claim 4, characterized in that, The motor overcurrent protection circuit also includes: The second resistor has its first end connected to the external controller and its second end connected to the second end of the transistor and the third end of the switching transistor. The third resistor has its first end connected to the anode of the first diode and the second end of the switching transistor, and its second end grounded.
8. The motor overcurrent protection circuit as described in claim 4, characterized in that, The capacitor subunit includes: Multiple first capacitors with different capacitance values are connected together at their first terminals to form the first terminal of the capacitor subunit. The selection device has one input terminal connected to the second terminal of the first capacitor, the output terminal of the selection device serving as the second terminal of the capacitor subunit, and the control terminal of the selection device connected to an external input device.
9. The motor overcurrent protection circuit as described in claim 1, characterized in that, The motor drive unit includes: The second diode has its anode serving as the second terminal of the motor drive unit and connected to the first terminal of the switching transistor in the motor control unit and the first terminal of the first capacitor in the protection delay unit. The cathode of the second diode serves as the first terminal of the motor drive unit and is connected to the power supply. The motor has a first end that is connected to the cathode of the second diode and serves as the first end of the motor drive unit, and a second end that is connected to the anode of the second diode and serves as the second end of the motor drive unit.
10. A massage device, characterized in that, The massage device includes a motor overcurrent protection circuit as described in any one of claims 1 to 9.