Quality detection device and detection system for built-in piezoresistor of DC brush motor

Abstract

The invention provides a quality detection device and detection system for a built-in piezoresistor of a DC brush motor, and relates to the technical field of detection. The quality detection device for the built-in piezoresistor of the DC brush motor comprises a power supply module and a detection module, the two power supply ends of the power supply module and the two detection ends of the detection module are used for being connected with the two power supply ends of the DC brush motor. The power supply module is used for outputting pulse signals to the direct-current brush motor when the direct-current brush motor is in a rotating state, and the pulse signals comprise pulse current signals or high-voltage pulse signals; and the detection module is used for detecting the actual pulse voltage between the two power supply ends of the DC brush motor while the power supply module outputs the pulse signal, and determining the quality of the built-in piezoresistor of the DC brush motor according to the actual pulse voltage. According to the scheme provided by the invention, the quality of the built-in piezoresistor of the finished DC brush motor can be detected, and the direct detection of the quality of the piezoresistor is realized.

Description

Technical Field

[0001] The present application relates to the field of detection technology, and in particular to a quality detection device and a detection system for a built-in varistor of a DC brushed motor. Background Art

[0002] When a brushed DC motor rotates at high speed, the brushes bounce as they slide across the motor's commutator. This can cause the motor's current circuit to frequently switch on and off, leading to a high self-inductance potential in the motor's rotor windings. This in turn generates strong sparks and produces significant electromagnetic interference to external electronic equipment. To suppress this electromagnetic interference, a varistor can be installed on the commutator inside the brushed DC motor to clamp the motor's winding self-inductance potential below a specified voltage. Therefore, it is particularly important to inspect the quality of the varistor built into brushed DC motors.

[0003] In related art, the quality of the varistors installed in the commutator of the armature (i.e., rotor) of a brushed DC motor is tested before the motor is assembled. The armature is a component of the motor, not the finished motor. The quality of the varistors changes during the assembly of motor components into the finished motor. Therefore, there is an urgent need to test the quality of the varistors built into the finished brushed DC motor. Given this, how to test the quality of the varistors built into the finished brushed DC motor is a technical problem that currently needs to be solved. Summary of the Invention

[0004] The present application provides a quality detection device and detection system for a built-in varistor of a DC brush motor to solve the problem of how to detect the quality of the built-in varistor of a finished DC brush motor, thereby realizing direct detection of the quality of the varistor.

[0005] In a first aspect, the present application provides a quality detection device for a built-in varistor of a brushed DC motor, wherein the varistor is arranged between two adjacent commutator segments of a commutator of the brushed DC motor; the quality detection device for a built-in varistor of a brushed DC motor comprises a power module and a detection module;

[0006] The first power supply terminal of the power supply module and the first detection terminal of the detection module are both used to connect to the first power supply terminal of the DC brush motor, and the second power supply terminal of the power supply module and the second detection terminal of the detection module are both used to connect to the second power supply terminal of the DC brush motor;

[0007] The power supply module is used to output a pulse signal to the DC brush motor when the DC brush motor is in a rotating state; the pulse signal includes a pulse current signal or a high-voltage pulse signal;

[0008] The detection module is used to detect the actual pulse voltage between the first power supply end and the second power supply end of the DC brush motor while the power supply module outputs the pulse signal, and determine the quality of the varistor built into the DC brush motor based on the actual pulse voltage.

[0009] In an optional embodiment, the power supply module is specifically configured to output a DC voltage to the DC brush motor to rotate the DC brush motor, and output the pulse signal to the DC brush motor when the DC brush motor is in a rotating state.

[0010] In an optional embodiment, the power supply module is a single power supply that can output both a DC voltage and a pulse signal;

[0011] Alternatively, the power supply module is a combined power supply including a DC voltage source and a pulse power source; wherein the pulse power source includes a pulse current source and / or a high-voltage pulse source.

[0012] In an optional embodiment, the power supply module is a combined power supply including a DC voltage source and a pulse power source, and the power supply module further includes a pulse blocker and a DC blocker;

[0013] The output end of the DC voltage source is connected in series with the pulse blocker and then connected in parallel between the first power supply end and the second power supply end;

[0014] The output end of the pulse power source is connected in series with the DC blocker and then connected in parallel between the first power end and the second power end;

[0015] The pulse blocker is used to block the pulse signal output by the pulse power supply;

[0016] The DC blocker is used to block the DC voltage output by the DC voltage source.

[0017] In an optional embodiment, the power supply module is specifically configured to simultaneously output the DC voltage and the pulse signal to the DC brush motor, wherein the DC voltage is used to control the rotation of the DC brush motor;

[0018] Alternatively, the power supply module is specifically used to output the DC voltage to the DC brush motor so that the DC brush motor starts to rotate, and then continues to output the DC voltage or stops outputting the DC voltage, and outputs the pulse signal to the DC brush motor when the DC brush motor is in a rotating state based on the continuously output DC voltage or is in a rotating state based on rotational inertia.

[0019] In an optional embodiment, the quality detection device for a built-in varistor of a brushed DC motor further includes a drag module; the drag module is configured to be mechanically connected to the brushed DC motor;

[0020] The drag module is used to drag the DC brushed motor to rotate.

[0021] In an optional embodiment, a synchronization signal line is connected between the power supply module and the detection module;

[0022] The power supply module is further configured to output a first synchronization signal to the detection module through the synchronization signal line while outputting the pulse signal, so as to notify the detection module to detect the actual pulse voltage between the first power supply end and the second power supply end of the brushed DC motor;

[0023] Alternatively, the power supply module is specifically configured to output the pulse signal to the brushed DC motor upon receiving the second synchronization signal output by the detection module through the synchronization signal line.

[0024] In an optional embodiment, the quality detection device for the DC brushed motor varistor further includes a scheduling module, and a scheduling signal line is electrically connected between the scheduling module, the power module, and the detection module.

[0025] The scheduling module is used to output a scheduling signal to the power module and the detection module through the scheduling signal line to notify the power module to output the pulse signal and simultaneously notify the detection module to detect the actual pulse voltage.

[0026] In an optional embodiment, the detection module is specifically used to detect the actual pulse voltage between the first power supply end and the second power supply end of the DC brush motor. When the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to a preset voltage difference threshold, it is determined that the quality of the varistor built into the DC brush motor is qualified; otherwise, it is determined that the quality of the varistor built into the DC brush motor is unqualified.

[0027] In a second aspect, the present application provides a detection system, including a DC brush motor with a built-in varistor and a quality detection device for a DC brush motor with a built-in varistor as described in any one of the first aspects above;

[0028] Wherein, the varistor is arranged between two adjacent commutator segments of the commutator of the brushed DC motor.

[0029] The quality detection device and detection system for the built-in varistor of the DC brush motor provided in the present application applies a pulse current signal or a high-voltage pulse signal to the two power supply ends of the DC brush motor during the rotation of the DC brush motor, and determines whether the quality of the varistor is qualified by detecting the actual pulse voltage at the two power supply ends of the DC brush motor. It can detect the quality of the built-in varistor of the finished DC brush motor and realize direct detection of the quality of the varistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of a volt-ampere characteristic curve of a varistor in related art;

[0031] Figure 2 This is a schematic diagram of the structure of a quality detection device for a built-in varistor of a brushed DC motor provided in an embodiment of the present application;

[0032] Figure 3 Schematic diagram of the physical equivalent model of a brushed DC motor with a built-in varistor in an embodiment of the present application;

[0033] Figure 4 One of the waveform diagrams of the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor in the embodiment of the present application changing with time;

[0034] Figure 5 This is a second waveform diagram of the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor according to the embodiment of the present application, which changes with time;

[0035] Figure 6 The third waveform diagram of the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor in the embodiment of the present application changes with time;

[0036] Figure 7 A schematic diagram of the structure of a power module provided in an embodiment of the present application;

[0037] Figure 8 This is a second structural diagram of a quality detection device for a built-in varistor of a brushed DC motor provided in an embodiment of the present application;

[0038] Figure 9 The third structural diagram of the quality detection device for a built-in varistor of a brushed DC motor provided in an embodiment of the present application;

[0039] Figure 10 This is the fourth structural schematic diagram of the quality detection device for the built-in varistor of the DC brushed motor provided in the embodiment of the present application. DETAILED DESCRIPTION

[0040] In this application, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a alone, b alone, or c alone can mean: a alone, b alone, c alone, a and b in combination, a and c in combination, b and c in combination, or a, b, and c in combination. Among them, a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

[0041] The terms "connected" and "connected," unless otherwise specified, should be understood broadly. For example, "connected" or "connected" in a circuit structure can refer not only to a physical connection, but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate component, as long as the circuit is interconnected. It can also refer to internal connectivity between two components. Signal connection can refer not only to signal connection through an electrical circuit but also to signal connection through a media medium, such as radio waves. Those skilled in the art will understand the specific meanings of the above terms in this application on a case-by-case basis.

[0042] When a brushed DC motor rotates at high speed, if the brush bounces while sliding at high speed on the surface of the motor's commutator, the motor's current circuit will frequently switch on and off, causing the motor's rotor winding inductance to generate a high self-inductance potential, which in turn generates strong electric sparks. The electric sparks will interfere with electronic equipment near the motor through electromagnetic radiation. At the same time, the high-frequency self-inductance potential will be transmitted along the motor power supply line to other electronic equipment that shares the DC power supply with the motor, thereby interfering with other electronic equipment. To suppress this electromagnetic interference, a varistor can be installed on the commutator inside the brushed DC motor. When a varistor is electrically connected in parallel between adjacent commutator segments of the brushed DC motor, the self-inductance potential (or self-inductance voltage) of the inductor coil is clamped by the varistor, clamping it below the specified voltage. It is not enough to break through the air and form electric sparks, so it will not radiate or conduct interference to other electronic equipment.

[0043] Specifically, Figure 1 The volt-ampere characteristic curve of the varistor is shown in the schematic diagram. Figure 1 As shown, V 1mAIt is the nominal varistor voltage value, that is, the voltage across the varistor when the current flowing through the varistor is 1mA. If the voltage across the varistor is less than V 1mA , the resistance value of the varistor is very large, then the varistor is equivalent to an electrical circuit, which does not affect the voltage across it. When the voltage applied across the varistor exceeds V 1mA If the voltage applied across the varistor exceeds the clamping voltage V C When the voltage of the varistor decreases sharply and the current flowing through the varistor increases sharply, the voltage across the varistor is clamped at V C Near the value.

[0044] The rotor of a brushed DC motor with a built-in varistor can be composed of an iron core, a shaft, a commutator, a varistor, and an enameled wire winding. The varistor is installed between adjacent commutator segments of the commutator. When assembling the rotor, the conductor copper on both sides of the varistor is welded to the commutator segments (generally conductor copper) on the commutator, that is, the two ends of each varistor are electrically connected to the adjacent commutator segments. In this way, multiple varistors can be distributed on the commutator of the rotor along the circumferential direction. For the commutator inside the brushed DC motor, there are multiple commutator segments, so there can also be multiple varistors. Based on this, the varistor can be a ring varistor. The number of varistors on the ring varistor body is equal to the number of commutator segments of the commutator, that is, there are as many varistors as there are commutator segments. For example, if the brushed DC motor has 3 commutator segments, then there are also 3 varistors.

[0045] Since multiple varistors are distributed along the circumferential direction on the commutator of the rotor, in order to detect the quality of each varistor, it is necessary to perform detection during the rotation of the DC brush motor.

[0046] In the related art, methods for detecting the quality of built-in varistors in DC brush motors during their rotation can include methods based on spark electromagnetic radiation monitoring and methods based on acoustic monitoring. For the spark electromagnetic radiation monitoring method, since DC brush motors with built-in varistors are generally small, miniature, high-speed motors, the position and direction of the electromagnetic radiation sensor (probe) pointing to the motor, the distance between the sensor and the motor, and the position of the motor when it is clamped to the fixture each time, all vary greatly, resulting in low repeatability. Furthermore, some motor housings have good electromagnetic shielding, and the signal picked up by the electromagnetic radiation sensor is relatively weak, greatly affecting the accuracy of the detection results. The acoustic monitoring method also suffers from the same problems as the spark electromagnetic radiation monitoring method, and is significantly affected by environmental background noise. Furthermore, the spark frequency generated by DC brush motors during high-speed rotation is high, reaching several megahertz (MHz) or more, while the frequency response range of existing microphones is limited to the audio range audible to the human ear, with a maximum of only 20 kHz. The upper frequency limit is only a few thousandths or even tens of thousandsths of the spark frequency limit, resulting in poor detection results. It can be seen that both methods indirectly detect the quality of the varistor, have low detection accuracy and are not very applicable.

[0047] In related technologies for directly testing varistors built into motors, the quality of the varistors on the motor rotor (or armature) is tested before the motor is assembled. However, the rotor is a motor component, not a finished motor. Therefore, the quality of the varistors built into a finished brushed DC motor cannot be tested, and the quality of the built-in varistors cannot be tested while the brushed DC motor is rotating. The quality of the varistors may change during the process of assembling motor components into a finished motor. Therefore, it is particularly important to test the quality of the varistors built into the finished motor after the motor components are assembled into the finished motor.

[0048] Based on this, an embodiment of the present application provides a quality detection device for a built-in varistor in a brushed DC motor. The varistor is arranged between two adjacent commutator segments of the brushed DC motor's commutator. The device can apply a pulse current signal or a high-voltage pulse signal to the two power supply terminals of the brushed DC motor while the brushed DC motor is rotating. The device determines the quality of the varistor by detecting whether the actual pulse voltage between the two power supply terminals of the brushed DC motor is clamped near the specified clamping voltage of the brushed DC motor. This allows direct detection of the built-in varistor in the brushed DC motor.

[0049] Among them, the specified clamping voltage refers to the actual pulse voltage between the two power supply terminals of the DC brush motor when a pulse current signal or a high-voltage pulse signal is applied when the quality of the built-in varistors of the DC brush motor are all qualified.

[0050] Figure 2 FIG1 shows one of the structural diagrams of the quality detection device for a built-in varistor of a DC brushed motor provided in an embodiment of the present application, with reference to FIG1 . Figure 2 As shown, the quality detection device for a built-in varistor of a brushed DC motor may include a power module 210 and a detection module 220. The first power supply terminal A1 of the power module 210 and the first detection terminal B1 of the detection module 220 are both used to connect to the first power supply terminal S1 of the brushed DC motor, and the second power supply terminal A2 of the power module 210 and the second detection terminal B2 of the detection module 220 are both used to connect to the second power supply terminal S2 of the brushed DC motor.

[0051] The power supply module 210 is used to output a pulse signal to the brushed DC motor when the brushed DC motor is in a rotating state. The pulse signal may include a pulse current signal or a high-voltage pulse signal.

[0052] The detection module 220 is used to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor while the power module 210 outputs a pulse signal, and determine the quality of the varistor built into the DC brush motor based on the actual pulse voltage.

[0053] For example, the first power terminal A1 of the power module 210 may be a positive power terminal of the power supply, and the second power terminal A2 may be a negative power terminal of the power supply.

[0054] Specifically, the power module 210 can output a DC voltage to the brushed DC motor to rotate it. Alternatively, a drive module mechanically connected to the brushed DC motor can drive the brushed DC motor to rotate. The drive module can include other motors that utilize the principle of mechanical torque to drive the brushed DC motor. For example, the motor in the drive module drives a transmission component to drive the brushed DC motor to rotate. When the brushed DC motor is rotating, the power module 210 outputs a pulse signal to the brushed DC motor.

[0055] For example, the power module 210 can be specifically configured to simultaneously output a DC voltage and a pulse signal to a brushed DC motor, thereby controlling the rotation of the brushed DC motor via the DC voltage. Alternatively, the power module 210 can be specifically configured to output a DC voltage to the brushed DC motor to initiate rotation of the brushed DC motor, then continue to output the DC voltage or stop outputting the DC voltage, and output a pulse signal to the brushed DC motor while the brushed DC motor is rotating due to the continuously output DC voltage or due to rotational inertia when the DC voltage is stopped.

[0056] For a brushed DC motor, when a DC power supply is connected to the first power supply terminal S1 and the second power supply terminal S2 of the motor, the current will flow from the positive end of the DC power supply through the first power supply terminal S1 of the motor, one of the brushes in the brush pair, a commutator segment, the enameled wire winding in the iron core, another commutator segment, the other brush of the brush pair, the second power supply terminal S2 of the motor, and then return to the negative end of the DC power supply. The motor rotates under the drive of the DC voltage.

[0057] The multiple varistors built into the DC brush motor are distributed and installed on the circumference of the commutator. Figure 3 A schematic diagram showing a physical equivalent model of a DC brushed motor with a built-in varistor is shown. Figure 3 As shown, RV is a varistor, L is the coil inductance of the rotor of the DC brush motor, and when the DC brush motor is in a rotating state, the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 can be detected.

[0058] Combine Figure 1 The varistor's volt-ampere characteristic curve shown in the figure shows that when the voltage across the varistor exceeds its nominal varistor voltage, the varistor's resistance decreases dramatically, thereby clamping the voltage across it near the clamping voltage. The varistor built into a brushed DC motor is electrically connected to the motor's power supply terminals. Therefore, the actual voltage at the motor's power supply terminals is clamped by the varistor. Thus, when the motor is rotating, the quality of the varistor built into the motor can be determined by applying a high-voltage pulse signal or a pulsed current signal to the motor's power supply terminals, simultaneously detecting the actual pulse voltage at both terminals, and comparing this actual pulse voltage with the specified clamping voltage.

[0059] Among them, there are two ways to apply high-voltage pulses to the power supply end of the DC brush motor: one is to directly output a high-voltage pulse signal to the power supply end of the DC brush motor; the other is to output a pulse current signal to the power supply end of the DC brush motor, so that the inductance of the DC brush motor passively generates a high-voltage self-inductance potential to obtain a high-voltage pulse.

[0060] Specifically, according to circuit theory, the self-inductance potential (or self-inductance voltage) E across the inductor can be expressed as the following formula (1):

[0061]

[0062] in, is the rate of change of current flowing through the inductor L, L m is the inductance of the inductor L.

[0063] Combine Figure 3 When a pulse current signal with a high rate of change is applied to inductor L, and there is no varistor connected in parallel across the inductor, a very high voltage pulse will be generated across inductor L due to the self-inductance potential. Obviously, the clamping voltage when a good varistor RV is connected in parallel across inductor L will be different from the clamping voltage when a defective varistor RV is connected in parallel across inductor L. Consequently, the actual pulse voltages at the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor electrically connected to inductor L will also be different. Therefore, by directly applying a pulse current signal between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor, the quality of the varistor built into the brushed DC motor can also be accurately tested.

[0064] It is understood that the minimum rate of change of the pulse current signal can be determined based on the clamping voltage of the varistor and the inductance of the brushed DC motor. This refers to the rate of change that occurs when the self-inductance potential E across the inductor equals the clamping voltage. In actual applications, the rate of change of the pulse current signal input to the brushed DC motor is greater than this minimum rate of change.

[0065] based on Figure 1 According to the curve principle, the detection module 220 can be specifically used to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. When the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it is determined that the quality of the built-in varistor of the DC brush motor is qualified; otherwise, it is determined that the quality of the built-in varistor of the DC brush motor is unqualified.

[0066] For example, the preset voltage difference threshold may be 0 or a voltage difference close to 0, and may be determined based on experience or through experimentation. When the voltage difference between the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it indicates that the voltage between the two power supply terminals of the brushed DC motor is clamped near the specified clamping voltage, indicating that the varistor is functioning as intended, and the quality of the varistor can be determined to be acceptable.

[0067] For example, Figure 4One of the waveforms of the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor is shown as a function of time. This waveform is a waveform when the quality of the varistor is qualified, that is, when the nominal varistor voltage of the built-in varistor of the DC brush motor is correct, the varistor is well installed, and the performance of the varistor is good. Figure 4 As shown, U DC Indicates the DC voltage that drives the DC brush motor to rotate, U Z It represents the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. The actual pulse voltage is clamped near the specified clamping voltage, that is, U Z ≈U C , where U C Indicates the specified clamping voltage.

[0068] For example, the detection module 220 can be specifically used to determine that the quality of the varistor built into the DC brush motor is unqualified when the voltage difference between the actual pulse voltage and the specified clamping voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor is greater than the preset voltage difference threshold, and the actual pulse voltage is greater than the specified clamping voltage. The types of unqualified conditions may include at least one of the nominal varistor voltage being too high (the varistor is installed with the wrong model), poor performance, poor soldering between the varistor and the commutator, the varistor not being installed, and the varistor being broken.

[0069] For example, Figure 5 The second waveform diagram shows the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor changing with time, referring to Figure 5 As shown, U DC Indicates the DC voltage that drives the DC brush motor to rotate, U H Indicates the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. The actual pulse voltage is greater than the specified clamping voltage, that is, U H >U C , and the voltage difference between the clamping voltage and the specified voltage is greater than the preset voltage difference threshold. In this case, it can be determined that the built-in varistor of the brushed DC motor is unqualified. The varistor may have a higher nominal varistor voltage (the wrong varistor model is installed, the nominal varistor voltage is too high), poor performance, a poor solder joint between the varistor and the commutator, the varistor is not installed, or the varistor is broken.

[0070] For example, the detection module 220 can also be specifically used to determine that the quality of the varistor built into the DC brush motor is unqualified when the voltage difference between the actual pulse voltage and the specified clamping voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor is greater than the preset voltage difference threshold, and the actual pulse voltage is less than the specified clamping voltage. The types of unqualified include the nominal varistor voltage being too low (the wrong model of varistor is installed).

[0071] For example, Figure 6 The third waveform diagram shows the actual voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor changing with time, referring to Figure 6 As shown, U DC Indicates the DC voltage that drives the DC brush motor to rotate, U L It represents the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. The actual pulse voltage is less than the specified clamping voltage, that is, U L <U C , and the voltage difference between the actual pulse voltage and the specified clamping voltage is greater than the preset voltage difference threshold. In this case, it can be determined that the varistor built into the brushed DC motor is unqualified. It may be that the nominal varistor voltage of the varistor is too low, that is, the wrong type of varistor is installed.

[0072] In this way, by comparing the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor with the specified clamping voltage, the quality of the built-in varistor of the DC brush motor can be determined based on the comparison result.

[0073] The quality detection device for a built-in varistor in a brushed DC motor provided in an embodiment of the present application applies a pulse current signal or a high-voltage pulse signal to the two power supply terminals of the brushed DC motor during the motor's rotation. The device then determines whether the varistor's quality is acceptable by detecting whether the actual pulse voltage between the two power supply terminals of the brushed DC motor is clamped near the motor's specified clamping voltage. This device can detect the quality of the built-in varistor in a finished brushed DC motor and directly detect the quality of the varistor. Compared to indirect detection methods in related technologies, this device improves the accuracy and reliability of quality detection of built-in varistors in brushed DC motors.

[0074] based on Figure 2 In one embodiment of the quality detection device for a built-in varistor in a brushed DC motor, the power module 210 may be a single power supply capable of outputting both a DC voltage and a pulse signal. Alternatively, the power module 210 may be a combined power supply including a DC voltage source and a pulse power source.

[0075] Taking the example of a power supply module 210 comprising a combined DC voltage source and a pulse power source, the power supply module 210 can output a DC voltage to a brushed DC motor via the DC voltage source to rotate the brushed DC motor, and can output a pulse signal to the brushed DC motor via the pulse power source. The pulse power source can include a pulse current source and / or a high-voltage pulse source. The pulse current source can output a pulse current signal, and the high-voltage pulse source can output a high-voltage pulse signal.

[0076] For example, taking the power supply module 210 as a combined power supply including a DC voltage source and a pulse power source, Figure 7 A schematic diagram of the structure of a power supply module provided in an embodiment of the present application is shown. Figure 7 As shown, the power supply module 210 includes a DC voltage source 211, a pulse power supply 212, a pulse blocker 213, and a DC blocker 214. The output end of the DC voltage source 211 is connected in series with the pulse blocker 213 and then connected in parallel between the first power supply terminal S1 and the second power supply terminal S2. The output end of the pulse power supply 212 is connected in series with the DC blocker 214 and then connected in parallel between the first power supply terminal S1 and the second power supply terminal S2.

[0077] For example, in Figure 7 In the figure, the positive output terminal of the DC voltage source 211 is connected to the first power supply terminal S1 of the DC brush motor through the pulse blocker 213, the positive output terminal of the pulse power supply 212 is connected to the first power supply terminal S1 of the DC brush motor through the DC blocker 214, and the negative output terminal of the DC voltage source 211 and the negative output terminal of the pulse power supply 212 are both connected to the second power supply terminal S2 of the DC brush motor.

[0078] The pulse blocker 213 is used to block the pulse signal output by the pulse power supply 212 ; and the DC blocker 214 is used to block the DC voltage output by the DC voltage source 211 .

[0079] For example, the pulse blocker 213 may be an inductor or an electrical switch, and the DC blocker 214 may be a capacitor, a diode, or an electrical switch.

[0080] In this way, by connecting a pulse blocker in series at the output end of the DC voltage source, the pulse signal output by the pulse power supply can be prevented from being electrically short-circuited by the DC voltage source. By connecting a DC blocker in series at the output end of the pulse power supply, the DC voltage source can be prevented from being electrically short-circuited by the pulse power supply.

[0081] based on Figure 2 In one embodiment, the quality detection device for the built-in varistor of the DC brushed motor of the corresponding embodiment includes: Figure 8 The second structural diagram of the quality detection device for the built-in varistor of the DC brush motor provided by the embodiment of the present application is shown. Figure 8As shown, a synchronization signal line SYNC is further connected between the power module 210 and the detection module 220. Accordingly, the power module 210 is further configured to output a first synchronization signal to the detection module 220 via the synchronization signal line SYNC while outputting the pulse signal, thereby notifying the detection module 220 to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0082] according to Figure 8 The quality detection device for a built-in varistor of a brushed DC motor shown in the figure can detect the quality of the built-in varistor of the brushed DC motor through the following steps 101 to 104.

[0083] Step 101: The power module 210 outputs a DC voltage to the DC brush motor, causing the DC brush motor to rotate.

[0084] Step 102: The power module 210 continues to output the DC voltage or stops outputting the DC voltage.

[0085] At this time, the DC brushed motor can continue to rotate based on the received DC voltage, or continue to rotate attenuatedly based on rotational inertia after the power module 210 stops outputting the DC voltage.

[0086] Step 103: The power module 210 outputs a pulse signal and, at the same time, outputs a first synchronization signal to the detection module 220 through the synchronization signal line SYNC to notify the detection module 220 to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0087] The pulse signal includes a high-voltage pulse signal or a pulse current signal.

[0088] Step 104: The detection module 220 compares the detected actual pulse voltage with the specified clamping voltage, and determines the quality of the varistor according to the comparison result.

[0089] Specifically, when the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it means that the voltage at the power supply end of the DC brushed motor is clamped near the specified clamping voltage, indicating that the varistor has played its due function, and it can be determined that the quality of the varistor is qualified; otherwise, it can be determined that the quality of the varistor is unqualified.

[0090] It is understood that in this embodiment, the power supply module 210 can be a single power supply that can output both a DC voltage and a pulse signal, or it can be a combined power supply including a DC voltage source and a pulse power source. If the power supply module 210 is a single power supply that can output both a DC voltage and a pulse signal, it can synthesize the output DC voltage and the pulse signal and apply them directly between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. If the power supply module 210 is a combined power supply including a DC voltage source and a pulse power source, the DC voltage source outputs the DC voltage, and the pulse power source outputs the pulse signal. The DC voltage can be non-zero or zero. When the DC voltage is non-zero, the DC brush motor rotates under the action of the DC voltage; when the DC voltage is zero, the DC brush motor rotates attenuated by inertia. This allows the quality of the built-in varistor of the DC brush motor to be detected while the DC brush motor is rotating.

[0091] The embodiment of the present application provides a quality detection device for a built-in varistor of a DC brush motor. In the process of controlling the rotation of the DC brush motor by DC voltage, a pulse signal is input between the first power supply terminal and the second power supply terminal of the DC brush motor through a power module to apply a pulse signal to the built-in varistor of the DC brush motor. At the same time as the power module outputs the pulse signal, the detection module can be notified through a synchronization signal line connected between the power module and the detection module to detect the actual pulse voltage between the first power supply terminal and the second power supply terminal of the DC brush motor, thereby achieving synchronization between the output of the pulse signal and the detection of the actual pulse voltage. Furthermore, by detecting whether the actual pulse voltage between the two power supply terminals of the DC brush motor is clamped near the specified clamping voltage, it is determined whether the quality of the varistor is qualified. The quality of the built-in varistor of the finished DC brush motor can be detected, and direct detection of the quality of the varistor is achieved. Compared with the indirect detection method in the related art, the accuracy and reliability of the quality detection of the built-in varistor of the DC brush motor are improved.

[0092] based on Figure 2 The quality detection device of the built-in varistor of the DC brush motor of the corresponding embodiment, in one embodiment, refers to Figure 8 As shown, a synchronization signal line SYNC is further connected between the power module 210 and the detection module 220. Accordingly, the power module 210 can be specifically configured to output a pulse signal to the brushed DC motor when the brushed DC motor is rotating and receives a second synchronization signal output by the detection module 220 via the synchronization signal line. This allows synchronization between the output of the pulse signal and the detection of the actual pulse voltage.

[0093] according to Figure 8The quality detection device for a built-in varistor of a brushed DC motor shown in the figure can detect the quality of the built-in varistor of the brushed DC motor through the following steps 201 to 204.

[0094] Step 201: The detection module 220 outputs first instruction information to the power module 210 through the synchronization signal line SYNC to notify the power module 210 to output a DC voltage to the DC brush motor to make the DC brush motor rotate.

[0095] Step 202: The detection module 220 outputs second instruction information to the power module 210 through the synchronization signal line SYNC to notify the power module 210 to continue outputting the DC voltage to the brushed DC motor or to stop outputting the DC voltage.

[0096] At this time, the DC brushed motor can continue to rotate based on the received DC voltage, or continue to rotate attenuatedly based on rotational inertia after the power module 210 stops outputting the DC voltage.

[0097] Step 203: The detection module 220 outputs a second synchronization signal to the power module 210 through the synchronization signal line SYNC to notify the power module 210 to output a pulse signal. At the same time, the detection module 220 detects the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor.

[0098] The pulse signal includes a high-voltage pulse signal or a pulse current signal.

[0099] Step 204: The detection module 220 compares the detected actual pulse voltage with the specified clamping voltage, and determines the quality of the varistor based on the comparison result.

[0100] Specifically, when the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it means that the voltage between the two power supply ends of the DC brushed motor is clamped near the specified clamping voltage, indicating that the varistor has played its due function, and it can be determined that the quality of the varistor is qualified; otherwise, it can be determined that the quality of the varistor is unqualified.

[0101] It is understood that in this embodiment, the power supply module 210 can be a single power supply that can output both a DC voltage and a pulse signal, or it can be a combined power supply including a DC voltage source and a pulse power source. If the power supply module 210 is a single power supply that can output both a DC voltage and a pulse signal, it can synthesize the output DC voltage and the pulse signal and apply them directly between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor. If the power supply module 210 is a combined power supply including a DC voltage source and a pulse power source, the DC voltage source outputs the DC voltage, and the pulse power source outputs the pulse signal. The DC voltage can be non-zero or zero. When the DC voltage is non-zero, the DC brush motor rotates under the action of the DC voltage; when the DC voltage is zero, the DC brush motor rotates attenuated by inertia. This allows the quality of the built-in varistor of the DC brush motor to be detected while the DC brush motor is rotating.

[0102] The present invention provides a quality detection device for a built-in varistor in a brushed DC motor. The detection module, via a synchronization signal line connected between the power module and the detection module, can notify the power module via the synchronization signal line to output a DC voltage to the brushed DC motor to control the motor's rotation. During the motor's rotation, the detection module, via the synchronization signal line, notifies the power module to input a pulse signal between the first and second power supply terminals of the brushed DC motor to apply a high-voltage pulse signal to the built-in varistor in the brushed DC motor. While the power module is outputting the pulse signal, the detection module detects the actual pulse voltage between the first and second power supply terminals of the brushed DC motor, achieving synchronization between outputting the pulse signal and detecting the actual pulse voltage. Furthermore, the detection module determines the quality of the varistor by detecting whether the actual pulse voltage between the two power supply terminals of the brushed DC motor is clamped near a specified clamping voltage. This device can detect the quality of the built-in varistor in a finished brushed DC motor and directly detect the quality of the varistor. Compared to indirect detection methods in related arts, this device improves the accuracy and reliability of quality detection of built-in varistors in brushed DC motors.

[0103] based on Figure 2 In one embodiment, the quality detection device for the built-in varistor of the DC brushed motor of the corresponding embodiment includes: Figure 9 The third structural diagram of the quality detection device for the built-in varistor of the DC brush motor provided by the embodiment of the present application is shown. Figure 9 As shown, the quality detection device for a built-in varistor of a brushed DC motor may further include a scheduling module 230 , which is electrically connected to the power module 210 and the detection module 220 via a scheduling signal line C.

[0104] Among them, the scheduling module 230 is used to simultaneously output a scheduling signal to the power supply module 210 and the detection module 220 through the scheduling signal line C to notify the power supply module 210 to output a pulse signal, and to notify the detection module 220 to simultaneously detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brushed motor.

[0105] For example, the scheduling module 230 may be a separate controller, processor, etc.

[0106] according to Figure 9 The quality detection device for a built-in varistor of a brushed DC motor shown in FIG. 1 can detect the quality of the built-in varistor of the brushed DC motor through the following steps 301 to 304 .

[0107] Step 301: The scheduling module 230 notifies the power module 210 to output a DC voltage to the brushed DC motor through the scheduling signal line C, so that the brushed DC motor rotates.

[0108] Step 302: The scheduling module 230 notifies the power module 210 via the scheduling signal line C to continue outputting the DC voltage or to stop outputting the DC voltage.

[0109] At this time, the DC brushed motor can continue to rotate based on the received DC voltage, or continue to rotate attenuatedly based on rotational inertia after the power module 210 stops outputting the DC voltage.

[0110] Step 303: The scheduling module 230 notifies the power module 210 to output a pulse signal through the scheduling signal line C, and simultaneously notifies the detection module 220 to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0111] The pulse signal includes a high-voltage pulse signal or a pulse current signal.

[0112] Step 304: The detection module 220 compares the detected actual pulse voltage with the specified clamping voltage, and determines the quality of the varistor according to the comparison result.

[0113] Specifically, when the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it means that the voltage between the two power supply ends of the DC brushed motor is clamped near the specified clamping voltage, indicating that the varistor has played its due function, and it can be determined that the quality of the varistor is qualified; otherwise, it can be determined that the quality of the varistor is unqualified.

[0114] The quality detection device for a built-in varistor of a DC brush motor provided in an embodiment of the present application can, during the rotation of the DC brush motor, notify the power module to output a pulse signal through a scheduling module electrically connected to the power module and the detection module respectively, and simultaneously notify the detection module to detect the actual pulse voltage between the first power supply terminal and the second power supply terminal S2 of the DC brush motor, thereby achieving synchronization between the output pulse signal and the detection of the actual pulse voltage. Furthermore, by detecting whether the actual pulse voltage between the two power supply terminals of the DC brush motor is clamped near the specified clamping voltage, it is determined whether the quality of the varistor is qualified. The quality of the built-in varistor of the finished DC brush motor can be detected, and direct detection of the quality of the varistor is achieved. Compared with the indirect detection method in the related art, the accuracy and reliability of the quality detection of the built-in varistor of the DC brush motor are improved.

[0115] based on Figure 2 In one embodiment, the quality detection device for the built-in varistor of the DC brushed motor of the corresponding embodiment includes: Figure 10 The fourth structural diagram of the quality detection device of the built-in varistor of the DC brush motor provided by the embodiment of the present application is shown. Figure 10 As shown, the quality detection device for a built-in varistor of a brushed DC motor may further include a drag module 240 , which is used for mechanical connection with the brushed DC motor.

[0116] The driving module 240 is used to drive the DC brush motor to rotate. The power supply module 210 can only be used to output a pulse signal to the DC brush motor, and the pulse signal includes a high-voltage pulse signal or a pulse current signal.

[0117] For example, the drive module 240 may include other motors that utilize the principle of mechanical torque to drive the brushed DC motor to rotate. For example, the drive module 240 may use its own motor to drive a transmission component to drive the brushed DC motor to rotate. When the brushed DC motor is rotating, the power module 210 outputs a pulse signal to the brushed DC motor.

[0118] according to Figure 10 The quality detection device for a built-in varistor of a brushed DC motor shown in FIG. 4 can detect the quality of the built-in varistor of the brushed DC motor through the following steps 401 to 403 .

[0119] Step 401: The drag module 240 drags the DC brush motor to rotate.

[0120] Step 402: The power module 210 outputs a pulse signal to the brushed DC motor, and the detection module 220 simultaneously detects an actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0121] The pulse signal includes a high-voltage pulse signal or a pulse current signal.

[0122] In an optional embodiment, combined with Figure 8 As shown, a synchronization signal line SYNC is further connected between the power module 210 and the detection module 220. While outputting a pulse signal to the brushed DC motor, the power module 210 can also output a first synchronization signal to the detection module 220 via the synchronization signal line SYNC to notify the detection module 220 to detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0123] Alternatively, the detection module 220 can output a second synchronization signal to the power module 210 through the synchronization signal line SYNC to notify the power module 210 to output a pulse signal. At the same time, the detection module 220 detects the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the DC brush motor.

[0124] In another optional embodiment, combined with Figure 9 As shown, the power module 210 and the detection module 220 can be electrically connected to the scheduling module 230 via a scheduling signal line C. The scheduling module 230 can simultaneously output a scheduling signal to the power module 210 and the detection module 220 to notify the power module 210 to output a pulse signal and to notify the detection module 220 to simultaneously detect the actual pulse voltage between the first power supply terminal S1 and the second power supply terminal S2 of the brushed DC motor.

[0125] Step 403: The detection module 220 compares the detected actual pulse voltage with the specified clamping voltage, and determines the quality of the varistor according to the comparison result.

[0126] Specifically, when the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to the preset voltage difference threshold, it means that the voltage between the two power supply ends of the DC brushed motor is clamped near the specified clamping voltage, indicating that the varistor has played its due function, and it can be determined that the quality of the varistor is qualified; otherwise, it can be determined that the quality of the varistor is unqualified.

[0127] The quality detection device for a built-in varistor in a brushed DC motor provided in an embodiment of the present application can use a drag module mechanically connected to the brushed DC motor to drive the brushed DC motor to rotate. During the rotation of the brushed DC motor, a pulse current signal or a high-voltage pulse signal is applied to the two power supply terminals of the brushed DC motor, and the quality of the varistor is determined by detecting the actual pulse voltage between the two power supply terminals of the brushed DC motor. This device can detect the quality of the built-in varistor of the finished brushed DC motor and directly detect the quality of the varistor. Compared with the indirect detection method in the related art, the accuracy and reliability of the quality detection of the built-in varistor of the brushed DC motor are improved.

[0128] The device embodiments described above are merely illustrative, wherein the modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. Those skilled in the art can understand and implement the present invention without inventive effort.

[0129] An embodiment of the present application further provides a detection system, comprising a brushed DC motor with a built-in varistor and a quality detection device for the built-in varistor of the brushed DC motor. The varistor is disposed between two adjacent commutator segments of the brushed DC motor. The quality detection device for the built-in varistor of the brushed DC motor can be the quality detection device for the built-in varistor of the brushed DC motor provided in any of the aforementioned embodiments of the present application. The two power supply terminals of the power supply module and the two detection terminals of the detection module of the built-in varistor of the brushed DC motor are respectively connected in parallel to the two power supply terminals of the brushed DC motor.

[0130] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the contents disclosed herein. This application is intended to cover any variations, uses, or adaptations herein that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered merely exemplary, and the true scope and spirit of this application are indicated by the claims.

Claims

1. A quality detection device for a built-in varistor of a brushed DC motor, characterized in that: The varistor is arranged between two adjacent commutator segments of the commutator of the DC brush motor; the quality detection device of the built-in varistor of the DC brush motor includes a power module and a detection module; The first power supply terminal of the power supply module and the first detection terminal of the detection module are both used to connect to the first power supply terminal of the DC brush motor, and the second power supply terminal of the power supply module and the second detection terminal of the detection module are both used to connect to the second power supply terminal of the DC brush motor; The power supply module is used to output a pulse signal to the DC brush motor when the DC brush motor is in a rotating state; the pulse signal includes a pulse current signal or a high-voltage pulse signal; The detection module is used to detect the actual pulse voltage between the first power supply end and the second power supply end of the DC brush motor while the power supply module outputs the pulse signal, and determine the quality of the varistor built into the DC brush motor based on the actual pulse voltage.

2. The quality detection device for a built-in varistor of a brushed DC motor according to claim 1, characterized in that: The power supply module is specifically configured to output a DC voltage to the DC brush motor to rotate the DC brush motor, and output the pulse signal to the DC brush motor when the DC brush motor is in a rotating state.

3. The quality detection device for a built-in varistor of a brushed DC motor according to claim 2, characterized in that: The power supply module is a single power supply that can output both DC voltage and pulse signal; Alternatively, the power supply module is a combined power supply including a DC voltage source and a pulse power source; wherein the pulse power source includes a pulse current source and / or a high-voltage pulse source.

4. The quality detection device for a built-in varistor of a brushed DC motor according to claim 3, characterized in that: The power supply module is a combined power supply including a DC voltage source and a pulse power source, and the power supply module also includes a pulse blocker and a DC blocker; The output end of the DC voltage source is connected in series with the pulse blocker and then connected in parallel between the first power supply end and the second power supply end; The output end of the pulse power supply is connected in series with the DC blocker and then connected in parallel between the first power supply end and the second power supply end; The pulse blocker is used to block the pulse signal output by the pulse power supply; The DC blocker is used to block the DC voltage output by the DC voltage source.

5. The quality detection device for a built-in varistor of a brushed DC motor according to claim 2, characterized in that: The power supply module is specifically configured to simultaneously output the DC voltage and the pulse signal to the DC brush motor, wherein the DC voltage is used to control the rotation of the DC brush motor; Alternatively, the power supply module is specifically used to output the DC voltage to the DC brush motor so that the DC brush motor starts to rotate, and then continues to output the DC voltage or stops outputting the DC voltage, and outputs the pulse signal to the DC brush motor when the DC brush motor is in a rotating state based on the continuously output DC voltage or is in a rotating state based on rotational inertia.

6. The quality detection device for a built-in varistor of a brushed DC motor according to claim 1, characterized in that: The quality detection device for the built-in varistor of the DC brush motor further includes a drag module; the drag module is used to be mechanically connected to the DC brush motor; The drag module is used to drag the DC brushed motor to rotate.

7. The quality detection device for a built-in varistor of a brushed DC motor according to any one of claims 1 to 6, characterized in that: A synchronization signal line is connected between the power supply module and the detection module; The power supply module is further configured to output a first synchronization signal to the detection module through the synchronization signal line while outputting the pulse signal, so as to notify the detection module to detect the actual pulse voltage between the first power supply end and the second power supply end of the brushed DC motor; Alternatively, the power supply module is specifically configured to output the pulse signal to the brushed DC motor upon receiving the second synchronization signal output by the detection module through the synchronization signal line.

8. The quality detection device for a built-in varistor of a brushed DC motor according to any one of claims 1 to 6, characterized in that: The quality detection device for a built-in varistor of a brushed DC motor further includes a scheduling module, wherein a scheduling signal line is electrically connected between the scheduling module, the power module, and the detection module; The scheduling module is used to output a scheduling signal to the power module and the detection module through the scheduling signal line to notify the power module to output the pulse signal and simultaneously notify the detection module to detect the actual pulse voltage.

9. The quality detection device for a built-in varistor of a brushed DC motor according to any one of claims 1 to 6, characterized in that: The detection module is specifically used to detect the actual pulse voltage between the first power supply end and the second power supply end of the DC brush motor. When the voltage difference between the actual pulse voltage and the specified clamping voltage is less than or equal to a preset voltage difference threshold, it is determined that the quality of the varistor built into the DC brush motor is qualified; otherwise, it is determined that the quality of the varistor built into the DC brush motor is unqualified.

10. A detection system, characterized in that: A DC brush motor comprising a built-in varistor and a quality detection device for a DC brush motor having a built-in varistor according to any one of claims 1 to 9; Wherein, the varistor is arranged between two adjacent commutator segments of the commutator of the brushed DC motor.

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