Device for measuring rotating speed and current of direct-current brushless motor

Abstract

The utility model belongs to the technical field of motor measurement, and particularly relates to a direct current brushless motor rotating speed current measuring device. The utility model provides a DC brushless motor rotating speed current measuring device, comprising a motor body and a measuring mechanism, the measuring mechanism is composed of a sheet metal housing, the measuring mechanism is provided with a plurality of display panels and detection interfaces, and the measuring mechanism is internally provided with a measuring module; a fixing groove is formed in one side of the measuring mechanism, guide rails are symmetrically arranged at the bottom of the fixing groove, a placement plate is slidably connected to the guide rails, a positioning frame is arranged on the placement plate, the motor body is inserted into the positioning frame, an output shaft is arranged on the motor body, and the motor body is connected with the positioning frame. Two ends of the motor body are respectively provided with a playground-shaped positioning block at the output shaft, and one side of the tail part of the motor body is provided with a wiring port.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor measurement, and particularly relates to a device for measuring the rotational speed and current of a brushless DC motor. Background Art

[0002] A brushless DC motor consists of a motor body and a driver, and is a typical mechatronic product. Since the brushless DC motor operates in an automatic control mode, it does not require an additional starting winding on the rotor like a synchronous motor under variable-frequency speed regulation during heavy-load starting, nor does it generate oscillations and loss of synchronization during sudden load changes. The brushless DC motor is the most ideal speed-regulating motor today and has been widely applied in many industries such as military, aerospace, and medical.

[0003] When measuring the rotational speed of an existing brushless DC motor, a tachometer is used for measurement. Marks are drawn or magnets are installed on the output shaft of the motor under test, and the tachometer is operated to identify signals through the reflection of light or magnetic induction, thereby measuring the rotational speed of the brushless DC motor. This rotational speed measurement method has relatively cumbersome operation procedures and requires high testing skills for testers, resulting in low measurement efficiency. Summary of the Utility Model

[0004] The technical problem to be solved by the utility model is that most existing brushless DC motors use the method of drawing marks or installing magnets on the output shaft of the motor under test, and identifying signals through the reflection of light or magnetic induction to measure the rotational speed of the brushless DC motor. This rotational speed measurement method has relatively cumbersome operation procedures and requires high testing skills for testers, resulting in low measurement efficiency.

[0005] To solve the above technical problems, the technical solution provided by the utility model is a device for measuring the rotational speed and current of a brushless DC motor, including a motor body and a measurement mechanism. The measurement mechanism is composed of a sheet metal housing, and a plurality of display panels and detection interfaces are arranged on the measurement mechanism. A measurement module is arranged inside the measurement mechanism; a fixing groove is arranged on one side of the measurement mechanism, guide rails are symmetrically arranged at the bottom of the fixing groove, a placement plate is slidably connected to the guide rails, a positioning frame is arranged on the placement plate, the motor body is inserted into the positioning frame, an output shaft is arranged on the motor body, "playground"-shaped positioning blocks are arranged at both ends of the motor body where the output shaft exits, and a wiring port is arranged on one side of the tail of the motor body.

[0006] Preferably, the measurement module is composed of an MCU control module, a comparison and amplification circuit, and a power supply. The MCU control module is electrically connected to a plurality of display panels, detection interfaces, and the comparison and amplification circuit respectively. The power supply is connected to the detection interface and is also connected to the comparison and amplification circuit simultaneously.

[0007] Preferably, the multiple display panels are LED digital display boards, and the number of the multiple display panels is two, which are respectively used for displaying current and rotational speed.

[0008] Preferably, both the detection interface and the wiring port are of a pluggable structure, and the detection interface and the wiring port are plugged through corresponding connecting wires, and both the detection interface and the wiring port are located on the same side of the measuring mechanism.

[0009] Preferably, a spring head and a knife switch fixing plate are respectively arranged on both sides of the placing plate inside the fixing groove. The knife switch fixing plate is located on the side of the placing plate close to the wiring port, and the spring head is located on the opposite side of the knife switch fixing plate. One end of the placing plate is shock-absorbed by the spring head, and the other end of the placing plate is limited by the knife switch fixing plate.

[0010] Preferably, one end of the knife switch fixing plate is rotatably connected to a fixing frame, and the other end is inserted into a U-shaped limiting knife rest, and the knife switch fixing plate has the same height as the placing plate.

[0011] Preferably, the positioning frame is composed of two directional plates arranged at both ends and multiple brackets in the middle. A U-shaped card slot matching the shape of the positioning block is arranged on the directional plate. The multiple brackets are equidistantly arranged in the middle between the two directional plates at both ends, and the upper end surfaces of the multiple brackets abut against the bottom of the motor body.

[0012] Preferably, the wiring port is perpendicular to the direction of the placing plate, which is convenient for wiring it from the side of the positioning frame.

[0013] The advantages of the present utility model compared with the prior art are as follows:

[0014] By taking advantage of the fact that there is torque fluctuation during the commutation process of the DC brushless motor, resulting in current fluctuation of the DC brushless motor, this DC brushless motor speed and current measurement device collects the current fluctuation signal of the DC brushless motor, and calculates the rotational speed after filtering the signal by a computer. This measurement method only requires the tester to fix the motor body and then wire it. The whole process is efficient and convenient, and can effectively reduce the requirements for the skills of the tester. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is the structure of a DC brushless motor speed and current measurement device of the present utility model Figure 1 .

[0016] Figure 2 is the structure of a DC brushless motor speed and current measurement device of the present utility model Figure 2 .

[0017] Figure 3This is a structural diagram of the placement rack of a rotational speed and current measurement device for a DC brushless motor of the present utility model.

[0018] Figure 4 This is a sectional three-dimensional structural diagram of the placement rack of a rotational speed and current measurement device for a DC brushless motor of the present utility model.

[0019] Figure 5 This is a circuit diagram of a rotational speed and current measurement device for a DC brushless motor of the present utility model.

[0020] As shown in the figure:

[0021] 1. Motor body; 2. Measuring mechanism; 3. Multiple display panels; 4. Detection interface; 5. Measurement module; 6. Fixed slot; 7. Guide rail; 8. Placement board; 9. Positioning frame; 10. Output shaft; 11. Positioning block; 12. Wiring port; 13. Spring head; 14. Knife switch fixing plate; 15. Fixing frame; 16. Limit knife rest; 17. Directional plate; 18. Multiple brackets; 19. Card slot. Detailed implementation manners

[0022] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0023] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, terms such as "installation", "provided with", "connection", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0024] Embodiment 1:

[0025] As shown in the appended Figures 1-4 description, a rotational speed and current measurement device for a DC brushless motor is characterized in that it includes a motor body 1 and a measuring mechanism 2. The measuring mechanism 2 is composed of a sheet metal housing, and multiple display panels 3 and a detection interface 4 are provided on the measuring mechanism 2. The multiple display panels 3 are LED digital display boards, and the number of the multiple display panels 3 is two, which are respectively used to display current and rotational speed. A measurement module 5 is arranged inside the measuring mechanism 2;

[0026] In the present utility model, a fixing groove 6 is provided on one side of the measuring mechanism 2. Guide rails 7 are symmetrically arranged at the bottom of the fixing groove 6. A placing plate 8 is slidably connected to the guide rails 7. Inside the fixing groove 6, a spring head 13 and a knife switch fixing plate 14 are respectively arranged on both sides of the placing plate 8. The knife switch fixing plate 14 is located on the side of the placing plate 8 close to the wiring port 12, and the spring head 13 is located on the opposite side of the knife switch fixing plate 14. One end of the placing plate 8 is shock-absorbed by the spring head 13, and the other end of the placing plate 8 is limited by the knife switch fixing plate 14. One end of the knife switch fixing plate 14 is rotatably connected to a fixing frame 15, and the other end is inserted into a U-shaped limiting knife rest 16. Moreover, the knife switch fixing plate 14 has the same height as the placing plate 8. A positioning frame 9 is arranged on the placing plate 8. The motor body 1 is inserted into the positioning frame 9. The positioning frame 9 is composed of two end directional plates 17 and multiple brackets 18 in the middle. A U-shaped card slot 19 matching the shape of the positioning block 11 is arranged on the directional plate 17. The multiple brackets 18 are equidistantly arranged in the middle between the two end directional plates 17, and the upper end surfaces of the multiple brackets 18 abut against the bottom of the motor body 1.

[0027] In the present utility model, an output shaft 10 is provided on the motor body 1. "Playground"-shaped positioning blocks 11 are arranged at both ends of the motor body 1 where the output shaft 10 exits. On one side of the tail of the motor body 1, a wiring port 12 is provided. Both the detection interface 4 and the wiring port 12 are plug-and-play structures, and the detection interface 4 and the wiring port 12 are plugged together through corresponding connecting wires. Both the detection interface 4 and the wiring port 12 are located on the same side of the measuring mechanism 2. The wiring port 12 is perpendicular to the direction of the placing plate 8, facilitating wiring to it from the side of the positioning frame 9.

[0028] As shown in the Figure 5 specification appendix, the measurement module 5 is composed of an MCU control module, a comparison and amplification circuit, and a power supply. Its MCU control module is electrically connected to multiple display panels 3, the detection interface 4, and the comparison and amplification circuit respectively. The power supply is connected to the detection interface 4 and is also connected to the comparison and amplification circuit at the same time.

[0029] When the present utility model is specifically implemented, the motor body 1 is inserted into the positioning frame 9 on the placing plate 8 according to the position of the wiring port 12 and the direction of the positioning block 11, thereby initially fixing and placing the motor body 1. Then, by pushing the placing plate 8, the placing plate 8 and the motor body 1 are pushed into the fixing groove 6 along the guide rails 7, so that one end of the placing plate 8 abuts against the spring head 13, and the other end is inserted into the limiting knife rest 16 on the other side through the rotation of the knife switch fixing plate 14 to fix the position of the placing plate 8 and prevent accidental contact with the motor body 1 during the test process;

[0030] Connect the wiring port 12 on one side of the motor body 1 to the detection interface 4 on the measuring mechanism 2 through a connecting wire, and supply power through a power source, so that the measuring mechanism 2 drives the motor body 1. Obtain its current signal through the current fluctuation during the driving process. The current signal is amplified by a comparison and amplification circuit and sent to the MCU control module for calculation. According to the acquisition frequency, measure the operating frequency of the motor based on the current signal fluctuation signal. Then, through the numerical averaging filtering algorithm, calculate that the motor speed (RPM) = frequency (HZ) * 60 (seconds). At the same time, the collected current value is averaged through an averaging algorithm and filtered by a software low-pass filter to obtain the current consumption value of the motor body 1. Through the display value, then display the speed and current through multiple display panels 3.

[0031] The above describes the present invention and its implementation manners. Such a description is not restrictive. What is shown in the specific implementation manners is only one of the implementation manners of the present invention, and the actual structure is not limited thereto. All in all, if those of ordinary skill in the art are inspired by it and design similar structural manners and embodiments to this technical solution without creative work without departing from the creative purpose of the present invention, they shall fall within the protection scope of the present invention.

Claims

1. A DC brushless motor speed and current measuring device, characterized in that: It includes a motor body and a measuring mechanism, wherein the measuring mechanism is composed of a sheet metal shell, and a plurality of display panels and detection interfaces are arranged on the measuring mechanism, and a measuring module is arranged inside the measuring mechanism; A fixing groove is provided on one side of the measuring mechanism, a guide rail is symmetrically provided at the bottom of the fixing groove, a placement plate is slidably connected to the guide rail, a positioning frame is provided on the placement plate, the motor body is plugged into the positioning frame, an output shaft is provided on the motor body, "playground" type positioning blocks are provided at both ends of the motor body at the output shaft, and a wiring port is provided on one side of the tail of the motor body.

2. A brushless DC motor speed and current measuring device according to claim 1, characterized in that: The measuring module is composed of an MCU control module, a comparison amplifier circuit and a power supply, wherein the MCU control module is electrically connected to a plurality of display panels, a detection interface and a comparison amplifier circuit respectively, and the power supply is connected to the detection interface and to the comparison amplifier circuit at the same time.

3. A DC brushless motor speed and current measuring device according to claim 1, characterized in that: The multiple display panels are LED digital display panels, and the number of the multiple display panels is two.

4. A DC brushless motor speed and current measuring device according to claim 1, characterized in that: The detection interface and the wiring port are both plug-in structures, and the detection interface and the wiring port are plugged in through corresponding connecting wires. The detection interface and the wiring port are both located on the same side of the measuring mechanism.

5. A DC brushless motor speed and current measuring device according to claim 1, characterized in that: The interior of the fixing groove is located on both sides of the placement plate and a spring head and a knife gate fixing plate are respectively provided. The knife gate fixing plate is located on the side of the placement plate close to the wiring port, and the spring head is located on the side opposite to the knife gate fixing plate. The spring head is used to dampen shock at one end of the placement plate, and the knife gate fixing plate is used to limit the other end of the placement plate.

6. A DC brushless motor speed current measuring device according to claim 5, characterized in that: One end of the knife switch fixing plate is rotatably connected to a fixing frame, and the other end is plugged into a limiting knife frame of a U-shaped structure, and the knife switch fixing plate has the same height as the placement plate.

7. A brushless DC motor speed and current measuring device according to claim 1, characterized in that: The positioning frame is composed of directional plates arranged at both ends and multiple brackets in the middle. The directional plate is provided with a U-shaped slot matching the shape of the positioning block. The multiple brackets are equidistantly arranged in the middle of the directional plates at both ends, and the upper end surfaces of the multiple brackets are against the bottom of the motor body.

8. A brushless DC motor speed and current measuring device according to claim 1, characterized in that: The wiring port is perpendicular to the direction in which the plate is placed.

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