Stepping motor control circuit and lifting device

Abstract

The invention discloses a stepping motor control circuit and a lifting device, and relates to the technical field of motor control, the stepping motor control circuit comprises a first power supply, a first switch, a stepping driver, a stepping motor and a delay switch, the stepping motor comprises a brake, a motor shaft and a motor coil; under the condition that the first switch is closed, the first power supply supplies power to the motor coil through the stepping driver, and the motor shaft is locked under the condition that the motor coil is electrified; and after the first switch is closed for a preset duration, the delay switch is closed, the first power source supplies power to the brake, and under the condition that the brake is powered on, the brake unlocks the motor shaft. The problem that the running reliability of the motor is insufficient is solved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of motor control technology, and in particular to a stepper motor control circuit and a lifting device. Background Art

[0002] During semiconductor chip testing, motors are typically used to lift and lower the probes mounted on the motors, allowing them to contact the chip surface for testing. However, due to insufficient motor reliability, the motor's load (probe) is prone to sudden drops during chip testing, potentially damaging the chip. For example, the load may drop immediately after the motor is powered on. Consequently, insufficient motor reliability currently exists.

[0003] The above content is only used to assist in understanding the technical solutions of the embodiments of the present application and does not constitute an admission that the above content is prior art. Summary of the Invention

[0004] The main purpose of the embodiments of the present application is to provide a stepper motor control circuit and a lifting device, aiming to solve the technical problem of insufficient motor operation reliability.

[0005] To achieve the above objectives, an embodiment of the present application provides a stepper motor control circuit, the stepper motor control circuit comprising a first power supply, a first switch, a stepper driver, a stepper motor, and a delay switch, the stepper motor comprising a brake, a motor shaft, and a motor coil surrounding the motor shaft;

[0006] A first end of the first switch is connected to the mains, a second end of the first switch is connected to the input end of a first power supply, an output end of the first power supply is connected to the input end of the stepper driver, an output end of the stepper driver is connected to the motor coil, a first end of the delay switch is connected to the output end of the first power supply, and a second end of the delay switch is connected to the brake;

[0007] When the first switch is closed, the first power supply supplies power to the motor coil via the stepper driver, and the motor coil locks the motor shaft when energized;

[0008] After the first switch is closed for a preset time, the delay switch is closed, and the first power supply supplies power to the brake. When the brake is powered on, the brake unlocks the motor shaft.

[0009] In one embodiment, the stepper motor control circuit further includes a second power supply, a second switch, an AC contactor and a time relay, the AC contactor includes an AC contactor coil and a first AC contact, and the time relay includes a time relay coil and a relay contact;

[0010] The input end of the second power supply is connected to the mains, the output end of the second power supply is connected to the first end of the second switch, and the second end of the second switch is connected to the AC contactor coil and the time relay coil;

[0011] The first switch is the first AC contact, and the delay switch is the relay contact;

[0012] When the second switch is closed, the AC contactor coil and the time relay coil are energized;

[0013] When the AC contactor coil is energized, the first switch is closed; after the time relay is energized for a preset time, the delay switch is closed.

[0014] In one embodiment, when the second switch includes an emergency stop switch and a second AC contact of the AC contactor;

[0015] The first end of the emergency stop switch is connected to the second power supply output end, and the second end of the emergency stop switch is connected to the first end of the AC contactor coil;

[0016] The first end of the second AC contact is connected to the output end of the second power supply, the second end of the second AC contact is connected to the first end of the time relay coil, and the second end of the time relay coil and the second end of the AC contactor coil are connected to the output end of the second power supply.

[0017] In one embodiment, when the emergency stop switch is closed, the AC contactor coil is energized;

[0018] When the AC contactor coil is energized, the second AC contact is closed and the time relay coil is energized.

[0019] In one embodiment, when the second switch is an emergency stop switch, a first end of the emergency stop switch is connected to an output end of the second power supply;

[0020] The second end of the emergency stop switch is connected to the first end of the AC contactor coil and the first end of the time relay coil;

[0021] The second end of the AC contactor coil and the second end of the time relay coil are connected to the output end of the second power supply.

[0022] In one embodiment, the first AC contact includes a first AC sub-contact and a second AC sub-contact, and the relay contact includes a first relay contact and a second relay contact;

[0023] The first end of the first AC sub-contact and the first end of the second AC sub-contact are connected to the mains, and the input end of the first power supply is connected to the second end of the first AC sub-contact and the second end of the second AC sub-contact;

[0024] The first end of the first relay contact and the first end of the second relay contact are both connected to the output end of the first power supply, and the second end of the first relay contact and the second end of the second relay are both connected to the brake in the stepper motor.

[0025] In one embodiment, when the emergency stop switch is disconnected, the AC contactor coil and the time relay coil lose power;

[0026] When the AC contactor coil loses power, the first AC contact is disconnected, the stepper driver loses power, and the motor coil loses power;

[0027] When the time relay coil loses power, the relay contacts are disconnected and the brake loses power.

[0028] In one embodiment, when the brake loses power, the brake locks the motor shaft of the stepper motor.

[0029] In one embodiment, the brake comprises a brake pad and a spring, a friction pad is provided on the motor shaft, and the brake pad is connected to the spring;

[0030] When the brake is energized, the spring is compressed and the brake pad moves away from the friction pad;

[0031] When the brake loses power, the spring is released and the brake pad is pressed against the friction pad to lock the motor shaft.

[0032] In addition, to achieve the above-mentioned purpose, an embodiment of the present application further provides a lifting device, including the stepping motor control circuit as described above.

[0033] One or more technical solutions proposed in the embodiments of the present application have at least the following technical effects: the stepper motor control circuit of the present application includes a first power supply, a first switch, a stepper driver, a stepper motor and a delay switch, and the stepper motor includes a brake, a motor shaft and a motor coil; the first end of the first switch is connected to the AC power, the second end of the first switch is connected to the input end of the first power supply, the output end of the first power supply is connected to the input end of the stepper driver, the output end of the stepper driver is connected to the motor coil, the first end of the delay switch is connected to the first power supply, and the second end of the delay switch is connected to the brake.

[0034] Therefore, when the first switch is closed, the first power supply can be connected to the mains power, and then the first power supply can power the motor coil through the stepper driver, and the motor coil can lock the motor shaft when powered on; and after the first switch is closed for a preset time, the delay switch will be closed, so that the brake is powered on after the preset time, and when the brake is powered on, the brake can unlock the lock on the motor shaft.

[0035] Because the motor coil is already energized before the brake is energized, and the motor coil can lock the motor shaft when energized, even if the brake releases the lock on the motor shaft after the motor coil is energized, the load corresponding to the stepper motor will not fall, thereby improving the reliability of the stepper motor operation. Therefore, by controlling the energization time of the brake to lag behind the energization time of the motor coil, the motor shaft of the stepper motor is always in a controlled state, thereby improving the reliability of the motor operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the embodiments of the present application, and together with the specification are used to explain the principles of the embodiments of the present application.

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 This is a module diagram of an embodiment of a stepper motor control circuit according to an embodiment of the present application;

[0039] Figure 2 This is a module diagram of another embodiment of the stepper motor control circuit of the present application;

[0040] Figure 3 This is a circuit connection diagram when the second switch in the stepping motor control circuit of an embodiment of the present application includes the second AC contact of the emergency stop switch;

[0041] Figure 4 This is a circuit connection diagram when the second switch in the stepping motor control circuit of the embodiment of the present application is an emergency stop switch;

[0042] Figure 5 This is a module diagram of another embodiment of the stepper motor control circuit in the embodiment of the present application.

[0043] Figure Number:

[0044] 100, stepper motor; 110, motor coil; 120, motor shaft; 130, brake; 200, stepper driver; 300, first power supply; KM, first switch; KT, delay switch; 400, AC power; 500, second power supply; KS, second switch; 610, AC contactor coil; 710, time relay coil 710; 600, AC contactor; 700, time contactor; KM1, first AC sub-contact; KM2, second AC sub-contact; KM3, second AC contact; KT1, first relay contact; KT2, second relay contact; S1, emergency stop switch; 131, spring; 132, brake pad; 121, friction plate.

[0045] The purpose, features and advantages of the embodiments of the present application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the embodiments of the present application and are not intended to limit the embodiments of the present application.

[0047] In order to better understand the technical solutions of the embodiments of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0048] During semiconductor chip testing, multiple probes are required to test the corresponding dies of the chip. The probes are uniformly fixed in a needle holder supported by a motor and raised and lowered by the motor. During testing and debugging, the probes need to be frequently fine-tuned to ensure the stability of the test results. At this time, the motor needs to be urgently stopped and the shaft locked to ensure it is fixed in a safe position. However, during the test, it was found that the load (needle holder) is prone to sudden drops, which in turn affects the safety and reliability of the test. Currently, there is a problem of insufficient motor operation reliability.

[0049] Based on this, the embodiment of the present application provides a stepper motor 100 control circuit, referring to Figure 1 , Figure 1 This is a schematic diagram of the module connections of the stepper motor 100 control circuit according to an embodiment of the present application. The stepper motor 100 control circuit includes a first power supply 300, a first switch KM, a stepper driver 200, a stepper motor 100, and a delay switch KT. The stepper motor 100 includes a brake 130, a motor shaft 120, and a motor coil 110 surrounding the motor shaft 120.

[0050] A first end of the first switch KM is connected to the mains 400, a second end of the first switch KM is connected to the input end of the first power supply 300, an output end of the first power supply 300 is connected to the input end of the stepper driver 200, an output end of the stepper driver 200 is connected to the motor coil 110, a first end of the delay switch KT is connected to the output end of the first power supply 300, and a second end of the delay switch KT is connected to the brake 130;

[0051] When the first switch KM is closed, the first power supply 300 supplies power to the motor coil 110 through the stepping driver 200, and the motor coil 110 locks the motor shaft 120 when energized;

[0052] After the first switch KM is closed for a preset time, the delay switch KT is closed, and the first power supply 300 supplies power to the brake 130 . When the brake 130 is powered, the brake 130 unlocks the motor shaft 120 .

[0053] It should be noted that the motor coil 110 included in the stepper motor 100 is wrapped around the motor shaft 120, and in this embodiment, a brake 130 is set in the stepper motor 100 so that the motor shaft 120 can be locked in time to prevent the stepper motor 100 from suddenly falling due to the corresponding load. The stepper driver 200 can power the motor coil 110 so that the motor coil 110 can lock the motor shaft 120 when energized. When the motor coil 110 loses power, the motor coil 110 cannot control the motor shaft 120 and cannot lock the motor shaft 120. The stepper motor 100 also includes a rotor, which is coaxially connected to the motor shaft 120, and the motor coil 110 is arranged around the rotor.

[0054] When the brake 130 is not energized, it locks the motor shaft 120. When the brake 130 is energized, it releases the lock on the motor shaft 120. In this embodiment, during the power-on process of the stepper motor 100, the energization time of the brake 130 always lags behind the energization time of the motor coil 110, thereby ensuring that the brake 130 is always in a controlled state, thereby preventing abnormal rotation of the motor shaft 120 and preventing the load corresponding to the stepper motor 100 from suddenly dropping.

[0055] The delay switch KT is closed after the first switch KM is turned on for a preset time, so that the energization time of the brake 130 always lags behind the motor coil 110. The preset time can be set based on actual conditions and is not specifically limited in this embodiment.

[0056] The first power supply 300 is connected to a first switch KM, which in turn is connected to the mains 400. When the first switch KM is disconnected, the first power supply 300 is de-energized, and thus the first power supply 300 does not power the stepper driver 200. The stepper motor 100 is also de-energized, and the brake 130 in the stepper motor 100 locks the motor shaft 120. When the first switch KM is closed, the first power supply 300 is energized, and thus the first power supply 300 can power the stepper driver 200.

[0057] In other embodiments, the first switch KM can also be disposed between the stepper driver 200 and the first power supply 300. For example, the first end of the first switch KM can be connected to the first power supply 300, and the second end of the first switch KM can be connected to the delay switch KT and the stepper driver 200. Thus, when the first switch KM is closed, the stepper driver 200 can also be powered, and the delay switch KT is also closed after the first switch KM is closed for a preset time period. In other words, in this case, the first power supply 300 is always powered. However, if the first switch KM is disposed between the first power supply 300 and the mains 400, circuit safety can be ensured because when the first switch KM is open, the first power supply 300 is also de-energized, thereby ensuring safety.

[0058] The stepper motor 100 control circuit of the embodiment of the present application includes a first power supply 300, a first switch KM, a stepper driver 200, a stepper motor 100 and a delay switch KT. The stepper motor 100 includes a brake 130, a motor shaft 120 and a motor coil 110; the first end of the first switch KM is connected to the AC power 400, the second end of the first switch KM is connected to the input end of the first power supply 300, the output end of the first power supply 300 is connected to the input end of the stepper driver 200, the output end of the stepper driver 200 is connected to the motor coil 110, the first end of the delay switch KT is connected to the first power supply 300, and the second end of the delay switch KT is connected to the brake 130.

[0059] Therefore, when the first switch KM is closed, the first power supply 300 can be connected to the AC power 400, and then the first power supply 300 can power the motor coil 110 through the stepper driver 200, and the motor coil 110 can lock the motor shaft 120 when powered on; and after the first switch KM is closed for a preset time, the delay switch KT will be closed, so that the brake 130 is powered on after the preset time, and when the brake 130 is powered on, the brake 130 can unlock the lock on the motor shaft 120.

[0060] Because the motor coil 110 is already energized before the brake 130 is energized, and the motor coil 110 can lock the motor shaft 120 when energized, even if the brake 130 releases the lock on the motor shaft 120 after the motor coil 110 is energized, the load corresponding to the stepper motor 100 will not fall, thereby improving the reliability of the operation of the stepper motor 100. Therefore, the embodiment of the present application controls the energization time of the brake 130 to lag behind the energization time of the motor coil 110, so that the motor shaft 120 of the stepper motor 100 is always in a controlled state, thereby improving the reliability of the motor operation.

[0061] In a possible embodiment, please refer to Figure 2 and Figure 3 The stepping motor 100 control circuit further includes a second power supply 500, a second switch KS, an AC contactor 600 and a time relay 700, wherein the AC contactor 600 includes an AC contactor coil 610 and a first AC contact, and the time relay 700 includes a time relay coil 710 and a relay contact;

[0062] The input end of the second power supply 500 is connected to the mains 400, the output end of the second power supply 500 is connected to the first end of the second switch KS, and the second end of the second switch KS is connected to the AC contactor coil 610 and the time relay coil 710;

[0063] The first switch KM is the first AC contact, and the delay switch KT is the relay contact;

[0064] When the second switch KS is closed, the AC contactor coil 610 and the time relay coil 710 are energized;

[0065] When the AC contactor coil 610 is energized, the first switch KM is closed; after the time relay 700 is energized for a preset time period, the delay switch KT is closed.

[0066] It should be noted that the control circuit of the stepper motor 100 includes a second power supply 500, a second switch KS, an AC contactor 600, and a time relay 700. The first switch KM is the first AC contact, the delay switch KT is the relay contact, and the time relay 700 is a switching device that can implement delay control. When the time relay coil 710 is energized, the relay contacts do not close immediately, but instead connect the circuit after a preset delay. For example, when the time relay coil 710 is energized, the relay contacts will close after a preset delay. The preset delay can be set based on actual conditions and is not specifically limited in this embodiment. In this embodiment, when the time relay coil 710 loses power, the relay contacts can be set to close immediately.

[0067] For example, refer to Figure 3 The AC contactor 600 may include multiple contacts. For example, the AC contact may include a first AC contact and a second AC contact KM3. The first switch KM is the first AC contact. Therefore, KM may refer to both the first switch KM and the first AC contact.

[0068] The input end of the second power supply 500 is also connected to the mains 400, which includes a neutral line, a live line, and a ground line. Figure 3 , Figure 3 In the figure, L is the live wire, N is the neutral wire, and E is the ground wire. The output end of the second power supply 500 is connected to the second switch KS. When the second switch KS is closed, the AC contactor coil 610 and the time relay coil 710 are energized. When the AC contactor coil 610 is energized, the first AC contact is also closed (that is, the first switch KM is closed), and the second AC contact KM3 is also closed. After the time relay coil 710 is energized for a preset period of time, the relay contact is closed (that is, the delay switch KT is closed).

[0069] In this embodiment, the stepper driver 200 can be powered by closing the second switch KS, thereby energizing the motor coil 110 .

[0070] This embodiment incorporates an AC contactor 600 and a time relay 700 in the circuit, thereby allowing the energization time of the brake 130 to lag behind the energization time of the motor coil 110 without relying on the host computer program. This reduces the probability of errors and improves circuit reliability. Furthermore, when circuit problems occur, they are easily troubleshooted, thereby improving circuit stability and ensuring the stability of the semiconductor test chip.

[0071] Furthermore, because this embodiment utilizes the stepper motor 100, the reliability of lifting is ensured. Compared to using the servo motor's BK signal to achieve stable control of lifting motion, this embodiment can reduce application costs. The stepper motor 100 brake 130 shaft locking process does not rely on the host computer program, resulting in a lower probability of error and easier troubleshooting when problems arise, thereby improving the overall operational reliability of the system.

[0072] In addition, Figure 3In the figure, the positive input terminal V+ of the stepper driver 200 is connected to the positive electrode of the first power supply 300, the negative input terminal V- of the stepper driver 200 is connected to the negative electrode of the first power supply 300, and the output terminal of the stepper driver 200 includes multiple output interfaces, for example, the output interfaces are A+, A-, B+ and B-, and each output interface is connected to the motor coil 110 in the stepper motor 100. For example, the coil of the stepper motor 100 includes a first motor coil 110 and a second motor coil 110, A+ and A- are respectively connected to the two ends of the first motor coil 110, and B+ and B- are respectively connected to the two ends of the second motor coil 110.

[0073] In one possible embodiment, please refer to Figure 3 , Figure 3 The circuit connection diagram of the second switch KS including the emergency stop switch S1 and the second AC contact KM3 is shown. Figure 3 M in the figure refers to the stepper motor 100. Figure 3 The motor shaft 120 , the motor coil 110 , and the brake 130 in the stepper motor 100 are not shown.

[0074] In the case where the second switch KS includes the emergency stop switch S1 and the second AC contact KM3 of the AC contactor 600;

[0075] The first end of the emergency stop switch S1 is connected to the output end of the second power supply 500, and the second end of the emergency stop switch S1 is connected to the first end of the AC contactor coil 610;

[0076] The first end of the second AC contact KM3 is connected to the output end of the second power supply 500, the second end of the second AC contact KM3 is connected to the first end of the time relay coil 710, and the second end of the time relay coil 710 and the second end of the AC contactor coil 610 are connected to the output end of the second power supply 500.

[0077] Furthermore, when the emergency stop switch S1 is closed, the AC contactor coil 610 is energized;

[0078] When the AC contactor coil 610 is energized, the second AC contact KM3 is closed, and the time relay coil 710 is energized.

[0079] It should be noted that the conduction and closing of the emergency stop switch S1 can be manually controlled, and the second AC contact KM3 can be set between the time relay coil 710 and the second power supply 500, so that when the emergency stop switch S1 is turned on, the AC contactor coil 610 is energized, and when the AC contactor coil 610 is energized, the second AC contact KM3 is closed, and when the second AC contact KM3 is closed, the time relay coil 710 is energized.

[0080] When the emergency stop switch S1 is disconnected, the AC contactor coil 610 loses power, and then the second AC contact KM3 also loses power, and then the time relay coil 710 also loses power.

[0081] Reference Figure 3 The output terminal of the second power supply 500 includes a positive electrode and a negative electrode. The first end of the emergency stop switch S1 can be connected to the positive electrode of the second power supply 500, and the negative electrode of the second power supply 500 can be connected to the second end of the AC contactor coil 610 and the second end of the time relay coil 710. The first end of the second AC contact KM3 can be connected to the second power supply 500, and the second end of the second AC contact KM3 can be connected to the second end of the time relay coil 710. The input terminal of the second power supply 500 also includes a live wire terminal and a neutral wire terminal. For example, L2 is the live wire terminal of the second power supply 500, and N2 is the neutral wire terminal of the second power supply 500.

[0082] The first end of the second switch KS can be the first end of the emergency stop switch S1 or the first end of the second AC contactor 600 , and the second end of the second switch KS can be the second end of the emergency stop switch S1 or the second end of the second AC contactor 600 .

[0083] This embodiment sets a second AC contact KM3 between the second power supply 500 and the time relay coil 710, thereby preventing the first end of the time relay coil 710 from being connected to the second end of the emergency stop switch S1 when the emergency stop switch S1 is closed and the time relay coil 710 and the AC contactor coil 610 are both energized. This can avoid unreliable circuits due to poor contact and reduce process complexity. Because when the second end of the emergency stop switch S1 is simultaneously connected to the first end of the time relay coil 710 and the first end of the AC contactor coil 610, a more complex process is required to ensure that the second end of the emergency stop switch S1 is reliably connected to the first end of the time relay coil 710 and the first end of the AC contactor coil 610.

[0084] Further, in another feasible embodiment, please refer to Figure 4 , Figure 4 The figure shows a circuit connection diagram of the stepping motor 100 control circuit when the second switch KS is the emergency stop switch S1;

[0085] When the second switch KS is an emergency stop switch S1, a first end of the emergency stop switch S1 is connected to an output end of the second power supply 500;

[0086] The second end of the emergency stop switch S1 is connected to the first end of the AC contactor coil 610 and the first end of the time relay coil 710;

[0087] A second end of the AC contactor coil 610 and a second end of the time relay coil 710 are connected to an output end of the second power supply 500 .

[0088] It should be noted that the second switch KS can also be the emergency stop switch S1, that is, the second AC contact KM3 can be omitted, and the time relay coil 710 and the AC contactor coil 610 can be energized when the emergency stop switch S1 is turned on, thereby reducing the complexity of the circuit.

[0089] When the second switch KS is the emergency stop switch S1, when the emergency stop switch S1 is closed, the time relay coil 710 and the AC contactor coil 610 are energized at the same time; when the emergency stop switch S1 is closed, the time relay coil 710 and the AC contactor coil 610 are de-energized at the same time.

[0090] In one possible embodiment, referring to Figure 3 , the first AC contact includes a first AC sub-contact KM1 and a second AC sub-contact KM2, and the relay contact includes a first relay contact KT1 and a second relay contact KT2;

[0091] The first end of the first AC sub-contact KM1 and the first end of the second AC sub-contact KM2 are connected to the mains 400, and the input end of the first power supply 300 is connected to the second end of the first AC sub-contact KM1 and the second end of the second AC sub-contact KM2;

[0092] The first end of the first relay contact KT1 and the first end of the second relay contact KT2 are both connected to the output end of the first power supply 300 , and the second end of the first relay contact KT1 and the second end of the second relay are both connected to the brake 130 in the stepping motor 100 .

[0093] It should be noted that the first end of the first AC sub-contact KM1 is connected to the live wire, the first end of the second AC sub-contact KM2 is connected to the neutral wire, the input terminals of the first power supply 300 include the live wire terminal L1 and the neutral wire terminal N1, the second end of the first AC sub-contact KM1 is connected to the live wire terminal, and the second end of the second AC sub-contact KM2 is connected to the neutral wire terminal. The first power supply 300 includes a positive electrode and a negative electrode. The first end of the first relay contact KT1 is connected to the positive electrode of the first power supply 300, and the first end of the second relay contact KT2 is connected to the negative electrode of the first power supply 300. The second end of the first relay contact KT1 and the second end of the second relay contact KT2 are connected to the brake 130.

[0094] The first AC contact includes a first AC sub-contact KM1 and a second AC sub-contact KM2. Since the first switch KM is the first AC contact, the first switch KM also includes a first AC sub-contact KM1 and a second AC sub-contact KM2.

[0095] The relay contacts include a first relay contact KT1 and a second relay contact KT2 , and the relay contacts are the delay switch KT, so the delay switch KT also includes a first relay contact KT1 and a second relay contact KT2 .

[0096] Furthermore, in a feasible embodiment, when the emergency stop switch S1 is disconnected, the AC contactor coil 610 and the time relay coil 710 lose power; when the AC contactor coil 610 loses power, the first AC contact is disconnected, the stepper driver 200 loses power, and the motor coil 110 loses power;

[0097] When the time relay coil 710 loses power, the relay contacts are disconnected and the brake 130 loses power.

[0098] Furthermore, when the brake 130 loses power, the brake 130 locks the motor shaft 120 of the stepper motor 100 .

[0099] It should be noted that when the emergency stop switch S1 is disconnected, the AC contactor coil 610 and the time relay coil 710 will lose power;

[0100] When the AC contactor 600 loses power, the first AC contact will also be disconnected, and then the stepper driver 200 will also lose power. The stepper driver 200 loses power, causing the motor coil 110 to also lose power. When the motor coil 110 loses power, the motor coil 110 cannot lock the current position of the motor shaft 120.

[0101] When the time relay coil 710 loses power, the relay contacts are disconnected and the brake 130 loses power. When the brake 130 loses power, the brake 130 can lock the current position of the motor shaft 120, thereby preventing the stepper motor 100 from suddenly dropping in response to the load.

[0102] When the first AC contact is disconnected and the stepper driver 200 loses power, the motor coil 110 no longer receives the current input by the stepper driver 200, but at this time there is still residual current in the motor coil 110, which can temporarily lock the motor shaft 120. At the same time, the time relay coil 710 also loses power, the relay contact will be immediately disconnected, and the brake 130 can immediately lock the motor shaft 120. When the power is cut off, it can also ensure that the load corresponding to the stepper motor 100 will not suddenly fall, thereby ensuring the safety of semiconductor testing.

[0103] In one possible embodiment, please refer to Figure 5 , Figure 5A schematic diagram of a module between a brake pad 132, a spring 131, a friction plate 121, and a motor shaft 120 is shown. The brake 130 includes a brake pad 132 and a spring 131. The friction plate 121 is provided on the motor shaft 120. The brake pad 132 is connected to the spring 131.

[0104] When the brake 130 is energized, the spring 131 is compressed, and the brake pad 132 moves away from the friction pad 121 ;

[0105] When the brake 130 loses power, the spring 131 is released, and the brake pad 132 is pressed against the friction pad 121 to lock the motor shaft 120 .

[0106] It should be noted that the brake 130 includes a brake pad 132 and a spring 131. When the brake 130 is energized, the spring 131 can be compressed, so that the brake pad 132 is away from the friction plate 121 on the motor shaft 120, and thus the brake 130 does not lock the motor shaft 120 when energized.

[0107] When brake 130 loses power, spring 131 is released. After being released, spring 131 presses brake pad 132 against friction pad 121, allowing brake 130 to lock the current position of motor shaft 120. Friction pad 121 increases the friction between brake pad 132 and motor shaft 120, thereby improving the reliability of brake 130 locking friction pad 121.

[0108] The lifting device provided in the embodiments of this application utilizes the stepper motor 100 control circuit of the aforementioned embodiments, aiming to address the technical issue of insufficient motor reliability. Compared to the prior art, the lifting device provided in the embodiments of this application achieves the same beneficial effects as the stepper motor 100 control circuit provided in the aforementioned embodiments. Other technical features of the lifting device are the same as those disclosed in the aforementioned embodiments and are not further elaborated here.

[0109] The lifting device can be any device for performing lifting and lowering movements. For example, it can be a probe station used in the semiconductor testing process. A stepper motor control circuit can be provided in the probe station. For example, in the probe station, a needle holder can be loaded on the stepper motor, and there can be multiple probes in the needle holder. By driving the stepper motor, the needle holder can be driven to perform lifting and lowering movements, thereby facilitating the testing of semiconductor chips.

[0110] The above are only preferred embodiments of the embodiments of the present application, and do not limit the patent scope of the embodiments of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of the embodiments of the present application, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the embodiments of the present application.

Claims

1. A stepper motor control circuit, characterized in that: The stepper motor control circuit includes a first power supply, a first switch, a stepper driver, a stepper motor, and a delay switch. The stepper motor includes a brake, a motor shaft, and a motor coil surrounding the motor shaft. A first end of the first switch is connected to the mains, a second end of the first switch is connected to the input end of a first power supply, an output end of the first power supply is connected to the input end of the stepper driver, an output end of the stepper driver is connected to the motor coil, a first end of the delay switch is connected to the output end of the first power supply, and a second end of the delay switch is connected to the brake; When the first switch is closed, the first power supply supplies power to the motor coil via the stepper driver, and the motor coil locks the motor shaft when energized; After the first switch is closed for a preset time, the delay switch is closed, and the first power supply supplies power to the brake. When the brake is powered on, the brake unlocks the motor shaft.

2. The stepping motor control circuit according to claim 1, wherein: The stepper motor control circuit further includes a second power supply, a second switch, an AC contactor and a time relay, wherein the AC contactor includes an AC contactor coil and a first AC contact, and the time relay includes a time relay coil and a relay contact; The input end of the second power supply is connected to the mains, the output end of the second power supply is connected to the first end of the second switch, and the second end of the second switch is connected to the AC contactor coil and the time relay coil; The first switch is the first AC contact, and the delay switch is the relay contact; When the second switch is closed, the AC contactor coil and the time relay coil are energized; When the AC contactor coil is energized, the first switch is closed; after the time relay is energized for a preset time, the delay switch is closed.

3. The stepping motor control circuit according to claim 2, wherein: In the case where the second switch includes an emergency stop switch and a second AC contact of the AC contactor; The first end of the emergency stop switch is connected to the second power supply output end, and the second end of the emergency stop switch is connected to the first end of the AC contactor coil; The first end of the second AC contact is connected to the output end of the second power supply, the second end of the second AC contact is connected to the first end of the time relay coil, and the second end of the time relay coil and the second end of the AC contactor coil are connected to the output end of the second power supply.

4. The stepping motor control circuit according to claim 3, wherein: When the emergency stop switch is closed, the AC contactor coil is energized; When the AC contactor coil is energized, the second AC contact is closed and the time relay coil is energized.

5. The stepping motor control circuit according to claim 2, wherein: When the second switch is an emergency stop switch, the first end of the emergency stop switch is connected to the output end of the second power supply; The second end of the emergency stop switch is connected to the first end of the AC contactor coil and the first end of the time relay coil; The second end of the AC contactor coil and the second end of the time relay coil are connected to the output end of the second power supply.

6. The stepping motor control circuit according to claim 2, wherein: The first AC contact includes a first AC sub-contact and a second AC sub-contact, and the relay contact includes a first relay contact and a second relay contact; The first end of the first AC sub-contact and the first end of the second AC sub-contact are connected to the mains, and the input end of the first power supply is connected to the second end of the first AC sub-contact and the second end of the second AC sub-contact; The first end of the first relay contact and the first end of the second relay contact are both connected to the output end of the first power supply, and the second end of the first relay contact and the second end of the second relay are both connected to the brake in the stepper motor.

7. The stepping motor control circuit according to any one of claims 2 to 6, wherein: When the emergency stop switch is disconnected, the AC contactor coil and time relay coil lose power; When the AC contactor coil loses power, the first AC contact is disconnected, the stepper driver loses power, and the motor coil loses power; When the time relay coil loses power, the relay contacts are disconnected and the brake loses power.

8. The stepping motor control circuit according to claim 7, wherein: In the event that the brake loses power, the brake locks the motor shaft of the stepper motor.

9. The stepping motor control circuit according to claim 8, wherein: The brake comprises a brake pad and a spring, a friction pad is provided on the motor shaft, and the brake pad is connected to the spring; When the brake is energized, the spring is compressed and the brake pad moves away from the friction pad; When the brake loses power, the spring is released and the brake pad is pressed against the friction pad to lock the motor shaft.

10. A lifting device, characterized in that: The lifting device includes the stepping motor control circuit according to any one of claims 1 to 9.

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