A new commutator and brush assembly for noise-reducing micromotor

Abstract

The present invention discloses a novel commutator and brush assembly of a noise-reducing micromotor, including a commutator connected to a micromotor rotor and a brush assembly in sliding contact with the surface of the commutator; the commutator includes an insulating sleeve and a plurality of commutator segments, and the brush assembly includes a brush holder, two brushes respectively partially in contact with the surface of the commutator, and two damping strips capable of reducing the vibration of the brushes. The brush assembly of the present invention has a small elastic force, and compared with a carbon brush, generates less noise, can abut the commutator with a small contact area, has good contact, reduces the noise generated between the commutator and the brush during operation, and can also quickly dissipate the heat generated during the operation of the micromotor, thereby increasing the service life of the micromotor; the brush assembly can contact with a copper-based wear-resistant sheet, avoiding the brush from contacting with burrs on the commutator segments to generate noise and sparks; the positioning block can improve the installation stability of the commutator segments, prevent the commutator segments from loosening during operation, and effectively reduce vibration and noise.

Description

Technical Field

[0001] The invention relates to the field of micromotors, and in particular to a novel commutator and a brush assembly of a noise-reducing micromotors. Background Art

[0002] Micromotors, whose full name is "microelectric motors", are often used in control systems or transmission mechanical loads to realize functions such as detection, analytical calculation, amplification, execution or conversion of electromechanical signals or energy.

[0003] The commutator, also known as the rectifier, is an important component of the DC motor. It is the component that allows the motor to continue to rotate. The function of the commutator is to convert the DC current passing through the brush into an alternating current in the winding or to convert the alternating electromotive force in the winding into a DC electromotive force at the brush end.

[0004] A brush, also known as a carbon brush, is a device that transfers energy or signals between the fixed part and the rotating part of an electric motor, generator or other rotating machinery. The brush is generally square in shape and is stuck on a metal bracket. There is a spring inside that presses it tightly against the shaft. When the motor rotates, the electrical energy can be transmitted to the coil through the commutator.

[0005] In the prior art, during the operation of this type of motor, the commutator needs to withstand the effects of centrifugal force and thermal stress, and cannot loosen or deform, which places high demands on the smoothness of the working surface and structural stability of the commutator segments. During the processing of the commutator segments on the market, it is easy to have flange burrs, which will cause the brushes to produce large noise and sparks during the sliding contact with the commutator segments, seriously affecting the service life and reliability of the commutator; at the same time, most of the brushes on the market are square carbon brush structures. During the sliding contact with the commutator surface, the larger the contact area between the brush and the commutator, the greater the noise and vibration generated between the commutator and the brush. The direct consequence of these problems is that the contacts of the micromotor are easily burned out, which in turn causes damage to the micromotor, seriously affecting the service life of the micromotor. Due to the large diameter of the commutator of this design and the fast relative linear speed, the noise is large, which brings high noise during operation. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a novel commutator and brush assembly of a noise-reducing micromotor which can effectively reduce the noise generated during operation, is simple to install, has high assembly efficiency and runs stably.

[0007] The technical solution of the present invention is as follows: a novel commutator and brush assembly of a noise-reducing micromotor, comprising a commutator connected to a rotor of the micromotor, and a brush assembly in sliding contact with a surface of the commutator;

[0008] The commutator comprises an axially penetrating insulating sleeve, a plurality of commutator segments, and a plurality of positioning blocks for fixing the commutator segments. A fixed disc is provided in the middle of the insulating sleeve, and the positioning blocks are arranged at intervals along the circumferential direction of the fixed disc.

[0009] A protrusion extending outward is provided at the bottom of one end of the positioning block away from the fixed disc, and bayonet holes are respectively provided in the positioning blocks on both sides of the protrusion;

[0010] The commutator segment is disposed around the outer wall of the insulating sleeve, and one end of the commutator segment is located between the bayonet holes of two adjacent positioning blocks, and radial grooves are respectively provided between the two adjacent commutator segments, and the protrusions are arranged in the radial grooves;

[0011] The brush assembly comprises a brush holder connected to the micromotor housing, two brushes respectively partially attached to the commutator surface, and two damping strips for reducing the vibration of the brushes, mounting holes are respectively provided on both sides of the brush holder, one end of the brush is connected to the mounting hole, and the other end of the brush is in contact with the commutator surface;

[0012] The electric brush is provided with a plurality of strip-shaped brush pieces which are parallel to each other, and the contacting parts of the strip-shaped brush pieces with the commutator are inlaid with silver-palladium-thorium alloy pieces.

[0013] By adopting the above technical solution, in the novel commutator of the noise-reducing micromotor and its brush assembly, the commutator segments are inlaid with silver-nickel-copper alloy sheets that are in sliding contact with the brushes.

[0014] By adopting the above-mentioned technical solutions, in the novel commutator of the noise-reducing micromotor and its brush assembly, the commutator further comprises a fixing ring, which is sleeved on the commutator segment and abuts against the side wall of the positioning block.

[0015] By adopting the above-mentioned technical solutions, in the novel commutator and brush assembly of the noise-reducing micromotor, a terminal portion is provided at one end of the commutator segment close to the positioning block, the commutator segments on both sides of the terminal portion are located within the bayonet of two adjacent positioning blocks, and the two sides of the terminal portion are respectively abutted against the side walls of the positioning block.

[0016] By adopting the above-mentioned technical solutions, in the novel commutator and brush assembly of the noise-reducing micromotor, the terminal part is in a T-shaped structure, and the terminal part includes a convex tooth section and a straight section. The bottom of the straight section is connected to the commutator segment, and the top of the straight section is connected to the convex tooth section. Arc structures are respectively provided on both sides of the convex tooth section, and arc notches are respectively provided on both sides of the straight section.

[0017] By adopting the above-mentioned technical solutions, in the novel commutator of the noise-reducing micromotor and its brush assembly, the insulating sleeve, the fixed disc and the plurality of positioning blocks are an integrally formed structure.

[0018] By adopting the above-mentioned technical solutions, in the novel commutator and brush assembly of the noise-reducing micromotor, the brush assembly also includes two conductive terminals connected to the power line, a step is provided at the bottom of the mounting hole, a cone block is provided in the middle of the conductive terminal and is engaged with the step, the top of the conductive terminal is connected to the brush, a slot is provided at one end of the mounting hole close to the commutator for facilitating the insertion of the brush, and a wiring port is provided at the bottom of the conductive terminal for facilitating the connection with the power line.

[0019] By adopting the above-mentioned technical solutions, in the novel commutator and brush assembly of the noise-reducing micromotor, the damping strip is arranged on the brush on the side facing away from the commutator.

[0020] By adopting the above-mentioned technical solutions, in the novel commutator of the noise-reducing micromotor and its brush assembly, the brush is made of silver-palladium alloy.

[0021] By adopting the above-mentioned technical solutions, in the novel commutator of the noise-reducing micromotor and its brush assembly, a rear cover connected to the micromotor housing is provided in the middle of the brush holder, and an oil-containing bearing is installed in the middle of the rear cover.

[0022] By adopting the above-mentioned technical schemes, the present invention arranges parallel strip brush pieces on the brush, and the brush can abut against the commutator with a smaller contact area, and has good contact, which effectively reduces the noise generated between the commutator and the brush during operation. At the same time, the parallel strip brush pieces can dissipate the heat generated in the friction process, thereby improving the heat dissipation rate of the micromotor during operation; the silver-copper-nickel alloy sheet embedded in the commutator segment can make the brush slide and abut against the silver-copper-nickel alloy sheet, thereby avoiding the noise and sparks generated by the contact between the brush and the burrs on the commutator segment, and effectively improving the service life of the commutator; a plurality of commutator segments are installed on the insulating sleeve through positioning blocks and fixing rings, which is convenient for installation and improves the production efficiency of assembly; the bayonet and protrusion arranged on the positioning block can improve the installation stability of the commutator segment, prevent the commutator segment from loosening during operation, and effectively reduce vibration and noise; the small diameter of the commutator leads to a slow linear speed during operation, thereby reducing noise and effectively improving the service life of the micromotor; the overall assembly process is simple, the production efficiency is high, the operation is low-noise, the heat dissipation is efficient, and the energy saving is good, and it can be promoted for use. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the commutator structure of the present invention;

[0025] Figure 3 It is a schematic diagram of the positioning block structure of the present invention;

[0026] Figure 4 It is a schematic diagram of the commutator segment structure of the present invention;

[0027] Figure 5 Schematic diagram of the brush structure of the present invention

[0028] Figure 6 It is a schematic diagram of the structure of the brush holder of the present invention;

[0029] Figure 7 for Figure 6 A partial enlarged view of area A. DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0031] like Figure 1 As shown, a novel commutator and brush assembly of a noise-reducing micromotor comprises a commutator 1 connected to the micromotor rotor and a brush assembly 2 in sliding contact with the surface of the commutator 1. In this embodiment, the commutator 1 can play a role in current commutation for the armature winding of the micromotor, and one end of the brush assembly 2 is connected to an external power source and the other end is in sliding contact with the surface of the commutator 1, which can play a conductive role to convert the alternating potential in the armature winding of the micromotor into a direct current output.

[0032] like Figure 2 As shown, the commutator 1 comprises an axially penetrating insulating sleeve 11, a plurality of commutator segments 12, and a plurality of positioning blocks 13 for fixing the commutator segments 12. A fixed disc 14 is provided in the middle of the insulating sleeve 11, and the positioning blocks 13 are arranged at intervals along the circumferential direction of the fixed disc 14. In this embodiment, the insulating sleeve 11 can be connected to the rotating shaft of the rotor, a fixed disc 14 is provided in the middle of the insulating sleeve 11, and the positioning blocks 13 are arranged at intervals along the circumferential direction of the fixed disc 14. The positioning blocks 13 can firmly fix the commutator segments 12 to prevent the commutator segments 12 from loosening during operation.

[0033] like Figure 3 As shown, further, the insulating sleeve 11, the fixed disc 14 and the plurality of positioning blocks 13 are an integrally formed structure. Such a configuration can improve the overall structural strength of the commutator 1 and prevent the positioning blocks 13 from deforming during operation, thereby affecting the service life of the commutator 1.

[0034] like Figure 3 As shown, a protrusion 131 extending outward is provided at the bottom of one end of the positioning block 13 away from the fixed disc 14 , and bayonet holes 130 are respectively provided in the positioning block 13 on both sides of the protrusion 131 .

[0035] like Figure 1 and Figure 2As shown, the commutator segment 12 is arranged around the outer wall of the insulating sleeve 11, and one end of the commutator segment 12 is located between the bayonet 130 of two adjacent positioning blocks 13, and radial grooves 100 are respectively provided between the two adjacent commutator segments 12, and the protrusion 131 is provided in the radial groove 100.

[0036] like Figure 1 As shown, further, the commutator 1 also includes a fixing ring 16 , which is sleeved on the commutator segment 12 and abuts against the side wall of the positioning block 13 .

[0037] like Figures 1 to 3 As shown, in this embodiment, one end of the commutator segment 12 is engaged in the bayonet 130 between the two positioning blocks 13, and the commutator segment 12 is compacted and fixed by the fixing ring 16. Such a setting improves the installation stability of the commutator segment 12 while also facilitating the user's disassembly and maintenance. When the damaged commutator segment 12 needs to be replaced, it is only necessary to slide the fixing ring 16 from the insulating sleeve 11, and then slide the commutator segment 12 out from the inner side of the bayonet 130 between the two positioning blocks 13. It is simple and convenient, and effectively improves the convenience of disassembly and installation of the circumferential device 1. In addition, the protrusion 131 of the positioning block 13 is arranged in the radial groove 100, which can effectively prevent the commutator segment 12 from being laterally displaced during operation, effectively reduce the vibration caused by the loose structure of the commutator 1 during operation, and achieve the effect of reducing noise.

[0038] like Figure 1 As shown, the brush assembly 2 includes a brush holder 21 connected to the micromotor housing, two brushes 22 respectively partially attached to the surface of the commutator 1, and two damping strips 23 for reducing the vibration of the brushes 22. The brush holder 21 is provided with mounting holes 210 on both sides, one end of the brush 22 is connected to the mounting hole 210, and the other end of the brush 22 is in contact with the surface of the commutator 1. In this embodiment, one end of the brush 22 is connected to the external power line, and the other end of the brush 22 is in sliding contact with the surface of the commutator 1. When the commutator 1 is rotating, the brush 22 can always be in contact with the surface of the commutator segment 12 to achieve current conduction.

[0039] like Figure 5As shown, the brush 22 is provided with a plurality of parallel strip brush pieces 220, and the contact portion between the strip brush piece 220 and the commutator 1 is inlaid with a silver-palladium-thorium alloy piece 24. In this embodiment, the silver-palladium-thorium alloy piece 24 can contact the surface of the commutator 1 to achieve the current conduction effect. The provision of the strip brush piece 220 can not only reduce the contact area between the brush 22 and the commutator 1, reduce the noise generated between the commutator 1 and the brush 22 during the rotation process, but also improve the heat dissipation rate of the micromotor. The silver-palladium-thorium alloy piece 24 will generate a certain amount of heat during the contact process with the surface of the commutator 1. This heat can be dissipated from the gap between the strip brush pieces 220 to prevent heat from accumulating on the brush 22 and generating sparks, thereby affecting the service life of the brush assembly 2.

[0040] like Figure 4 As shown, further, the commutator segment 12 is inlaid with a silver-nickel-copper alloy sheet 15 that is in sliding contact with the brush 22. Burrs are inevitably generated on the surface of the commutator segment 12 during the processing process. When the brush 22 of the micromotor contacts the commutator segment 12 for commutation, it will scrape on the burrs of the commutator segment 12, thereby generating large noise and sparks. In this embodiment, the silver-nickel-copper alloy sheet 15 inlaid on the commutator segment 12 allows the brush 22 of the micromotor to directly contact the silver-nickel-copper alloy sheet 15. Since the surface of the silver-nickel-copper alloy sheet 15 is relatively smooth, the noise and sparks generated by the commutator 1 during operation can be effectively reduced. In addition, the silver-nickel-copper alloy sheet 15 has good wear resistance, which can effectively increase the service life of the commutator 1.

[0041] like Figures 2 to 4 As shown, further, a terminal portion 17 is provided at one end of the commutator segment 12 close to the positioning block 13, and the commutator segments 12 on both sides of the terminal portion 17 are located within the bayonet 130 of the two adjacent positioning blocks 13, and the two sides of the terminal portion 17 are respectively in contact with the side walls of the positioning blocks 13. In this embodiment, the terminal portion 17 can be connected to the armature winding in the micromotor to connect the corresponding part of the armature winding with each commutator segment 12. The commutator segments 12 on both sides of the terminal portion 17 are engaged with the bayonet 130 of the two adjacent positioning blocks 13, which can improve the installation stability of the commutator segments 12; the two sides of the terminal portion 17 are respectively in contact with the side walls of the positioning blocks 13, which can prevent the terminal portion 17 from causing the commutator segments 12 to shift during operation.

[0042] like Figure 4As shown, further, the terminal portion 17 is a T-shaped structure, and the terminal portion 17 includes a convex tooth section 171 and a straight section 172. The bottom of the straight section 172 is connected to the commutator segment 12, and the top of the straight section 172 is connected to the convex tooth section 171. The two sides of the convex tooth section 171 are respectively provided with arc structures 1710, and the two sides of the straight section 172 are respectively provided with arc notches 1720. In this embodiment, the straight section 172 can facilitate the winding of the coil of the armature winding, and the convex tooth section 171 can provide a limiting and fixing function for the coil of the armature winding. The setting of the arc structure 1710 and the arc notch 1720 can facilitate the introduction of the coil of the armature winding.

[0043] like Figure 1 and Figure 5 As shown, further, the damping strip 23 is arranged on the brush 22 on the side facing away from the commutator 1. In this embodiment, the damping strip 23 can provide a pressure to the brush 22, so that the end surface of the brush 22 close to the commutator 1 can slide and press on the surface of the copper-based wear-resistant sheet 15, so as to reduce the vibration generated by the brush 22 during the sliding process on the surface of the commutator 1, and improve the service life of the brush assembly 2.

[0044] Furthermore, the brush 22 is made of silver-palladium alloy. In this embodiment, the silver-palladium alloy not only has good wear resistance, preventing the brush 22 from wearing during the contact process with the commutator 1, but also can increase the arc starting voltage of the contact material, making it difficult to generate sparks, preventing the surface of the commutator 1 from being burned, and avoiding electromagnetic interference.

[0045] like Figures 5 to 7 As shown, further, the brush assembly 2 also includes two conductive terminals 25 connected to the power line, the bottom of the mounting hole 210 is provided with a step 2101, the middle of the conductive terminal 25 is provided with a cone block 251 that is mutually engaged with the step 2101, the top of the conductive terminal 25 is connected to the brush 22, the end of the mounting hole 210 close to the commutator 12 is provided with a slot 2102 for convenient insertion of the brush 22, and the bottom of the conductive terminal 25 is provided with a wiring port 250 that is convenient for connection with the power line. In this embodiment, the conductive terminal 25 can realize the current conduction connection between the external power line and the brush 22, and the step 2101 set at the bottom of the mounting hole 210 can be quickly engaged with the cone block 251 in the middle of the conductive terminal 25, so as to facilitate the disassembly and assembly of the conductive terminal 25 and improve the convenience of damage and maintenance of the brush assembly 2.

[0046] like Figure 1 As shown, further, a rear cover 26 connected to the micromotor housing is provided in the middle of the brush holder 21, and an oil-containing bearing 27 is installed in the middle of the rear cover 26. In this embodiment, the oil-containing bearing 27 provided in the middle of the rear cover 26 can be connected and installed with the shaft of the micromotor to reduce the friction generated by the shaft during rotation and reduce friction noise.

[0047] By adopting the above-mentioned technical schemes, the present invention arranges parallel strip brush pieces on the brush, and the brush can abut against the commutator with a smaller contact area, and has good contact, which effectively reduces the noise generated between the commutator and the brush during operation. At the same time, the parallel strip brush pieces can dissipate the heat generated in the friction process, thereby improving the heat dissipation rate of the micromotor during operation; the silver-copper-nickel alloy sheet embedded in the commutator segment can make the brush slide and abut against the silver-copper-nickel alloy sheet, thereby avoiding the noise and sparks generated by the contact between the brush and the burrs on the commutator segment, and effectively improving the service life of the commutator; a plurality of commutator segments are installed on the insulating sleeve through positioning blocks and fixing rings, which is convenient for installation and improves the production efficiency of assembly; the bayonet and protrusion arranged on the positioning block can improve the installation stability of the commutator segment, prevent the commutator segment from loosening during operation, and effectively reduce vibration and noise; the small diameter of the commutator leads to a slow linear speed during operation, thereby reducing noise and effectively improving the service life of the micromotor; the overall assembly process is simple, the production efficiency is high, the operation is low-noise, the heat dissipation is efficient, and the energy saving is good, and it can be promoted for use.

[0048] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel commutator and brush assembly for a noise-reducing micromotor, characterized in that: It includes a commutator connected to the micromotor rotor, and a brush assembly in sliding contact with the surface of the commutator; The commutator comprises an axially penetrating insulating sleeve, a plurality of commutator segments, and a plurality of positioning blocks for fixing the commutator segments. A fixed disc is provided in the middle of the insulating sleeve, and the positioning blocks are arranged at intervals along the circumferential direction of the fixed disc. A protrusion extending outward is provided at the bottom of one end of the positioning block away from the fixed disc, and bayonet holes are respectively provided in the positioning blocks on both sides of the protrusion; The commutator segment is disposed around the outer wall of the insulating sleeve, and one end of the commutator segment is located between the bayonet holes of two adjacent positioning blocks, and radial grooves are respectively provided between the two adjacent commutator segments, and the protrusions are arranged in the radial grooves; The brush assembly comprises a brush holder connected to the micromotor housing, two brushes respectively partially attached to the commutator surface, and two damping strips for reducing the vibration of the brushes, mounting holes are respectively provided on both sides of the brush holder, one end of the brush is connected to the mounting hole, and the other end of the brush is in contact with the commutator surface; The electric brush is provided with a plurality of strip-shaped brush pieces which are parallel to each other, and the contacting parts of the strip-shaped brush pieces with the commutator are inlaid with silver-palladium-thorium alloy pieces.

2. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The commutator segments are inlaid with silver-nickel-copper alloy sheets that are in sliding contact with the brushes.

3. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The commutator also includes a fixing ring, which is sleeved on the commutator segment and abuts against the side wall of the positioning block.

4. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The commutator segment is provided with a terminal portion at one end close to the positioning block, the commutator segments on both sides of the terminal portion are located within the slots of two adjacent positioning blocks, and both sides of the terminal portion are respectively in contact with the side walls of the positioning block.

5. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 4 is characterized in that: The terminal part has a T-shaped structure, and includes a convex tooth section and a straight section. The bottom of the straight section is connected to the commutator segment, and the top of the straight section is connected to the convex tooth section. Arc structures are respectively provided on both sides of the convex tooth section, and arc notches are respectively provided on both sides of the straight section.

6. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The insulating sleeve, the fixed disc and the plurality of positioning blocks are an integrally formed structure.

7. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The brush assembly also includes two conductive terminals connected to the power cord, a step is provided at the bottom of the mounting hole, a cone block is provided in the middle of the conductive terminal and is engaged with the step, the top of the conductive terminal is connected to the brush, a slot is provided at one end of the mounting hole close to the commutator for easy insertion of the brush, and a wiring port is provided at the bottom of the conductive terminal for easy connection to the power cord.

8. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The damping strip is arranged on the brush on the side facing away from the commutator.

9. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: The brush is made of silver-palladium alloy.

10. The novel commutator and brush assembly of the noise-reducing micromotor according to claim 1 is characterized in that: A rear cover connected to the micromotor housing is arranged in the middle of the brush holder, and an oil-containing bearing is arranged in the middle of the rear cover.

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