Micromotor piezoresistor structure capable of preventing short circuit

Abstract

The utility model discloses a micromotor piezoresistor structure capable of preventing short circuit. The micromotor piezoresistor structure comprises a rotating shaft, a rotor winding, a commutator and a piezoresistor, the commutator is provided with six welding pins at equal intervals along the circumferential direction; the piezoresistor comprises an annular base body and three electrode layers; a non-welding area is formed between every two adjacent electrode layers, and the non-welding areas are the annular base body which is partially exposed; the non-welding area is of a splayed structure which is narrow outside and wide inside. The three welding pins in the commutator can be respectively welded with the electrode layer, and the other three welding pins are not contacted with the non-welding area, so that the short circuit caused by the contact between the welding pins which do not need to be welded and the edge of the non-welding area can be prevented under the condition that the current impedance of the electrode layer is not influenced, and the service life of the commutator is prolonged. And deviation of a welding point is effectively avoided, so that the current can flow according to an expected path, and the operation reliability of the micromotor is improved.

Description

Technical Field

[0001] The utility model relates to the field of micro motors, in particular to a micro motor varistor structure for preventing short circuit. Background Art

[0002] The armature is an important part of the motor, specifically the rotor part of the DC motor. It is made of a conductive coil and is usually fixed on the shaft. The armature plays a key role in generating the electromagnetic field and interacting with the magnetic field in the motor. When the current passes through the armature, a corresponding magnetic field is generated according to the direction of the current and the position of the armature. This magnetic field interacts with the stator magnetic field in the motor, thereby generating a torque to drive the motor to rotate. By constantly changing the direction of the current in the armature, the normal operation and commutation operation of the motor can be achieved.

[0003] During the operation of the motor, there may be sudden changes in power supply voltage, grid failure, and voltage fluctuations in the motor itself. These voltage changes may have adverse effects on the motor. For example, overvoltage may cause insulation breakdown or damage to the motor. Therefore, varistors are generally configured in the armature to improve the overvoltage and overcurrent protection performance of the motor.

[0004] In the prior art, since the varistor configured in the micromotor is small in size and the electrode area is even smaller, welding point deviation often occurs during the welding process of the varistor, causing the micromotor to easily have an internal short circuit during operation.

[0005] Therefore, the prior art has defects and needs to be improved. Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide a micro-motor varistor structure which has a stable structure and can avoid welding deviation and prevent short circuit.

[0007] To achieve this purpose, the utility model adopts the following technical solutions: a micro-motor varistor structure for preventing short circuit, including a rotating shaft, a rotor winding, a commutator and a varistor;

[0008] The commutator and the rotor winding are respectively arranged at the upper and lower ends of the rotating shaft, and the varistor is arranged between the commutator and the rotor winding;

[0009] The commutator is provided with six welding pins equidistantly along the circumferential direction;

[0010] The varistor comprises an annular substrate and three electrode layers;

[0011] The three electrode layers are arranged equidistantly along the circumferential direction of the surface of the annular substrate, and a non-welding area is formed between two adjacent electrode layers, and the non-welding area is a portion of the annular substrate exposed;

[0012] The non-welding area is in an eight-shaped structure that is narrow outside and wide inside;

[0013] Three of the welding pins of the commutator are respectively connected to the electrode layer by welding, and the other three welding pins of the commutator are not in contact with the non-welding area.

[0014] By adopting the above technical solution, in the short-circuit-proof micromotor varistor structure, the electrode layer is a silver-plated electrode layer.

[0015] By adopting the above-mentioned technical solutions, in the micro-motor varistor structure for preventing short circuit, the thickness of the electrode layer is 10-120 μm.

[0016] By adopting the above-mentioned technical solutions, in the micro-motor varistor structure for preventing short circuit, the inner diameter of the annular base is larger than the outer diameter of the commutator.

[0017] By adopting the above-mentioned technical solutions, in the short-circuit-proof micro-motor varistor structure, the annular base is made of ceramic material.

[0018] By adopting the above-mentioned technical solutions, in the short-circuit-proof micro-motor varistor structure, the width of the electrode layer is equal to the width of the annular substrate.

[0019] By adopting the above-mentioned technical solutions, in the micro-motor varistor structure for preventing short circuit, the commutator is provided with six commutator segments at equal intervals along the circumferential direction;

[0020] An insulating gap is provided between two adjacent commutator segments.

[0021] By adopting the above-mentioned technical solutions, in the micro-motor varistor structure for preventing short circuit, the welding pin is connected to the bottom of the commutator segment.

[0022] By adopting the above-mentioned technical solutions, in the short-circuit-proof micro-motor varistor structure, the side length of the non-welding area close to the welding pin is greater than the width of the welding pin.

[0023] By adopting the above-mentioned technical solutions, in the micro-motor varistor structure for preventing short circuit, the thickness of the annular base is 1-4 mm, and the width of the annular base is 2-6 mm.

[0024] Compared with the prior art, the utility model has the following beneficial effects:

[0025] The varistor of the utility model comprises an annular substrate and three electrode layers, and a non-welding area is formed between two adjacent electrode layers. The non-welding area is a partially exposed annular substrate, and the non-welding area is an eight-shaped structure that is narrow outside and wide inside. Three welding pins in the commutator can be welded to the electrode layers respectively, and the other three welding pins do not contact the non-welding area. Such an arrangement can prevent the welding pins that do not need to be welded from contacting the edge of the non-welding area to cause a short circuit without affecting the current impedance of the electrode layer, and effectively avoid deviation of the welding point, thereby ensuring that the current can flow along the expected path and improving the operating reliability of the micromotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0027] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0028] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0029] Figure 2 This is a schematic diagram of the structure of the varistor of the utility model;

[0030] Figure 3 It is a schematic diagram of the top structure of the utility model. DETAILED DESCRIPTION

[0031] In order to make the utility model's purpose, features, and advantages more obvious and easy to understand, the following will be combined with the drawings in the utility model embodiments to clearly and completely describe the technical solutions in the utility model embodiments. Obviously, the embodiments described below are only part of the utility model embodiments, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0032] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0033] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0034] like Figures 1 to 3 As shown, the embodiment of the utility model provides a micro-motor varistor structure for preventing short circuit, including a rotating shaft 10, a rotor winding 20, a commutator 30 and a varistor 40;

[0035] The commutator 30 and the rotor winding 20 are respectively arranged at the upper and lower ends of the rotating shaft 10, and the varistor 40 is arranged between the commutator 30 and the rotor winding 20; the function of the rotating shaft 10 is to support and connect the rotor winding 20, the commutator 30 and other components. The rotating shaft 10 enables the rotor winding 20 to rotate and transmits the movement of the rotor winding 20 to other components, thereby realizing the operation of the micromotor; the rotor winding 20 is a coil winding installed on the rotating shaft 10, which can generate a magnetic field and a current. When the current passes through the rotor winding 20, according to the direction of the current The interaction with the magnetic field will generate a torque, causing the rotor winding 20 to rotate; the commutator 30 can change the direction of the current to ensure the normal operation of the rotor winding 20. Through the operation of the commutator 30, the current can flow through different parts of the rotor winding 20 in the correct order, thereby generating a continuous rotational torque; the varistor 40 can detect current changes and provide appropriate resistance to limit current and voltage. When the current or voltage exceeds the set threshold, the varistor 40 will automatically adjust its resistance value to protect the micromotor from damage caused by overcurrent and overvoltage.

[0036] The commutator 30 is provided with six welding pins 301 equidistantly along the circumferential direction, and the six welding pins 301 are all folded upwards. The varistor 40 includes an annular substrate 401 and three electrode layers 402. The three electrode layers 402 are equidistantly arranged along the circumferential direction of the surface of the annular substrate 401. A non-welding area 403 is formed between two adjacent electrode layers 402. The non-welding area 403 is a partially exposed annular substrate 401. The non-welding area 403 is an eight-shaped structure with a narrow outside and a wide inside. Three of the welding pins 301 of the commutator 30 are respectively connected to the electrode layer 402 by welding, and the other three welding pins 301 of the commutator 30 do not contact the non-welding area 403. Such a configuration can prevent the welding pins 301 that do not need to be welded from contacting the edge of the non-welding area 403 and causing a short circuit without affecting the current impedance of the electrode layer 402, and effectively avoid deviation of the welding points, thereby ensuring that the current can flow along the expected path and improving the operating reliability of the micromotor.

[0037] Furthermore, the electrode layer 402 is a silver-plated electrode layer 402. Silver is an excellent conductive material with high electrical conductivity. By plating the electrode layer 402 with silver, it can be ensured that the current can be smoothly conducted in the electrode layer 402, reducing resistance loss and improving the efficiency of the micromotor; and silver also has good welding performance and can be reliably welded to other metal materials to ensure the reliability and stability of the welding point.

[0038] Furthermore, the thickness of the electrode layer 402 is 10-120 μm;

[0039] In this embodiment, the thickness of the electrode layer 402 is 50 μm.

[0040] Furthermore, the inner diameter of the annular base 401 is larger than the outer diameter of the commutator 30. By designing the inner diameter of the annular base 401 to be slightly larger than the outer diameter of the commutator 30, the commutator 30 can be conveniently inserted into the annular base 401, thereby simplifying the assembly process and reducing the difficulty and time of assembling the micromotor.

[0041] Furthermore, the annular base 401 is made of ceramic material. Ceramic material has a high resistance value, so that the ceramic varistor can achieve a large resistance change range. In addition, the temperature coefficient of the ceramic material is low, that is, the resistance value is not sensitive to temperature changes, so that the ceramic varistor 40 can provide stable resistance characteristics in a wide temperature range.

[0042] like Figure 2As shown, further, the width of the electrode layer 402 is equal to the width of the annular substrate 401. Such a setting can minimize the resistance loss of the electrode layer 402; if the width of the electrode layer 402 is narrow, the current will pass through a longer electrode path when passing through, which increases the resistance; by making the width of the electrode layer 402 equal to the width of the annular substrate 401, the resistance can be minimized and the efficiency of the circuit can be improved.

[0043] like Figure 1 and Figure 3 As shown, further, the commutator 30 is provided with six commutator segments 302 at equal intervals along the circumferential direction, and an insulating gap 303 is provided between two adjacent commutator segments 302. The provision of the insulating gap 303 can effectively isolate adjacent commutator segments 302 to prevent the current from short-circuiting on the commutator 30. When the current passes through the commutator 30, the air or insulating material in the insulating gap 303 can provide electrical isolation to prevent the current from flowing directly between the commutator segments 302, thereby maintaining normal circuit function.

[0044] like Figure 1 As shown, further, the welding pin 301 is connected to the bottom of the commutator segment 302; in the process of current being input from the welding pin 301 to the commutator segment 302, the current can be distributed and transmitted through the commutator segment 302, ensuring that the current can be effectively transmitted from the pin to the commutator segment 302, thereby ensuring the normal operation of the commutator 30.

[0045] like Figure 3 As shown, further, the side length of the non-welding area 403 close to the welding pin 301 is greater than the width of the welding pin 301. Such a setting can provide sufficient spacing and isolation for the welding pin 301, avoid electrical short circuit between the welding pin 301 and the varistor 40, ensure the correct transmission of current between the welding pins 301, and prevent unnecessary interference or loss.

[0046] Further, the thickness of the annular base 401 is 1-4 mm, and the width of the annular base 401 is 2-6 mm. In this embodiment, the thickness of the annular base 401 is 2 mm, and the width of the annular base 401 is 4 mm.

[0047] The varistor 40 of the utility model includes an annular substrate 401 and three electrode layers 402, and a non-welding area 403 is formed between two adjacent electrode layers 402. The non-welding area 403 is a partially exposed annular substrate 401, and the non-welding area 403 is an eight-shaped structure with a narrow outside and a wide inside. The three welding pins 301 in the commutator 30 can be welded to the electrode layer 402 respectively, and the other three welding pins 301 do not contact the non-welding area 403. Such an arrangement can prevent the welding pins 301 that do not need to be welded from contacting the edge of the non-welding area 403 to cause a short circuit without affecting the current impedance of the electrode layer 402, and effectively avoid the deviation of the welding point, thereby ensuring that the current can flow along the expected path, and improving the operating reliability of the micromotor.

[0048] As described above, the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A micro-motor varistor structure for preventing short circuit, characterized in that: It includes a rotating shaft, a rotor winding, a commutator and a varistor; The commutator and the rotor winding are respectively arranged at the upper and lower ends of the rotating shaft, and the varistor is arranged between the commutator and the rotor winding; The commutator is provided with six welding pins equidistantly along the circumferential direction; The varistor comprises an annular substrate and three electrode layers; The three electrode layers are arranged equidistantly along the circumferential direction of the surface of the annular substrate, and a non-welding area is formed between two adjacent electrode layers, and the non-welding area is a portion of the annular substrate exposed; The non-welding area is in an eight-shaped structure that is narrow outside and wide inside; Three of the welding pins of the commutator are respectively connected to the electrode layer by welding, and the other three welding pins of the commutator are not in contact with the non-welding area.

2. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The electrode layer is a silver-plated electrode layer.

3. The micro-motor varistor structure for preventing short circuit according to claim 2, characterized in that: The thickness of the electrode layer is 10-120 μm.

4. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The inner diameter of the annular base is greater than the outer diameter of the commutator.

5. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The annular base is made of ceramic material.

6. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The width of the electrode layer is equal to the width of the annular base.

7. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The commutator is provided with six commutator segments at equal intervals along the circumferential direction; An insulating gap is provided between two adjacent commutator segments.

8. The micro-motor varistor structure for preventing short circuit according to claim 7, characterized in that: The welding pin is connected to the bottom of the commutator segment.

9. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The side length of the non-welding area close to the welding pin is greater than the width of the welding pin.

10. The micro-motor varistor structure for preventing short circuit according to claim 1, characterized in that: The thickness of the annular base is 1-4 mm, and the width of the annular base is 2-6 mm.

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