CN210297418U

CN210297418U - Micro motor

Info

Publication number: CN210297418U
Application number: CN201921729461.7U
Authority: CN
Inventors: 梁小华; 陈建能; 亢汉宁; 高蓓; 郭鹏; 王世年; 余勋灿; 林李健; 邓坤; 王治勇
Original assignee: Shenzhen Longde Technology Co ltd
Current assignee: Huizhou Longde Technology Co ltd
Priority date: 2019-10-15
Filing date: 2019-10-15
Publication date: 2020-04-10
Anticipated expiration: 2029-10-15

Abstract

The utility model discloses a micro motor, which comprises a rotor, a middle plate component and a shell, wherein the middle plate component is provided with a carbon brush hole and a fixed groove, a brush box and a carbon brush are arranged in the carbon brush hole, the carbon brush slides in the brush box in one way, the middle plate component is also provided with a torsion spring, one end of the torsion spring is clamped into the fixed groove, and the other end of the torsion spring is contacted with the carbon brush and pushes the carbon brush to be pressed towards the rotor; the position of the shell where the carbon brush is installed is provided with a heat dissipation hole; the rotor comprises an iron core, a commutator and a rotating shaft, wherein the iron core and the commutator are both arranged on the rotating shaft, and the radius of the center of any iron core opening and the radius of the center of the notch of any commutator form an included angle larger than 0 degree.

Description

Micro motor

Technical Field

The utility model relates to the field of motors, especially, relate to a micromotor.

Background

The traditional brush direct current motor generally adopts a spring arm structure to install the electric brush, the pressure and the reversing angle of the brush with the spring arm structure can change along with the abrasion of the carbon brush, and the pressure and the reversing angle are limited by the service time of carbon crystals, so that the motor has the defects of short service life, unstable performance during the use, low motor efficiency, poor overall performance and the like.

The gap of the traditional brush direct current motor commutator segment is just opposite to the notch of the iron core in the radial angle, the matching mode is not beneficial to optimizing the commutation effect, sparks are easy to generate, and the reliability and the service life of the motor are reduced.

The traditional brush direct current motor has no carbon brush heat dissipation holes on the shell, which easily causes the problems of carbon brush overheating, medium plate component softening and deformation and the like.

SUMMERY OF THE UTILITY MODEL

In order to solve the defects in the prior art, the utility model provides a micromotor which can keep the reversing angle of a motor constant and prolong the service life of the motor.

The technical scheme of the utility model is that, a micro motor is provided, which comprises a rotor, a middle plate component and a shell, wherein the middle plate component is provided with a carbon brush hole and a fixed groove, a brush box and a carbon brush are arranged in the carbon brush hole, the carbon brush slides in the brush box in one way, the middle plate component is also provided with a torsion spring, one end of the torsion spring is clamped into the fixed groove, and the other end of the torsion spring contacts the carbon brush and pushes the carbon brush to compress in the direction of the rotor; the position of the shell where the carbon brush is installed is provided with a heat dissipation hole; the rotor comprises an iron core, a commutator and a rotating shaft, wherein the iron core and the commutator are both arranged on the rotating shaft, and the radius of the center of any iron core opening and the radius of the center of the notch of any commutator form an included angle larger than 0 degree. The center of the core opening and the center of the commutator slot are not on the same diameter. The brush box is fixed by the middle plate assembly, the carbon brush can only slide along one direction of the brush box in the brush box, the constancy of the reversing angle of the motor is guaranteed, the torsion spring pushes the carbon brush to compress the rotor of the motor with relatively constant force, the pressure of the carbon brush is guaranteed to be stable in the service life of the motor, the heat dissipation holes are formed in the position of the carbon brush of the shell, and the reliability of the motor is improved. The center of the iron core opening and the center of the commutator groove form an included angle, and the included angle is kept unchanged when the rotor rotates.

Furthermore, a rear cover matched with the machine shell is further arranged, and the middle plate component is fixed on the rear cover. By adopting the structure, the carbon brush on the middle plate component is fixed at the axial position of the motor.

Further, the torsion spring includes a coil portion and two extension portions connected to the coil, the two extension portions being respectively located at an upper side and a lower side of the torsion spring. The two extending sections of the torsion spring form an included angle, the included angle is reduced after the torsion spring is installed in the middle plate assembly, the included angle changes along with the abrasion of the carbon brush in the running process of the motor, and the pressure of the carbon brush is always kept within an allowable range.

Furthermore, beryllium copper material is adopted for the torsion spring.

Furthermore, one section of the extension section of the torsion spring is provided with a hook-shaped structure, and the other section of the extension section of the torsion spring is a linear structure.

Further, the brush box is fixed on the middle plate component.

Further, the carbon brush is tightly attached to the surface of the commutator.

The principle and the using method of the micro motor are that the axial position of the carbon brush is fixed and the radial angle is not changed when the motor runs, the carbon brush is tightly attached to the surface of the commutator under the action of the torsion spring, the carbon brush and the commutator generate friction along with the use of the motor, the length of the carbon brush is shortened, but the commutation angle and the pressure of the carbon brush are kept relatively constant. After the motor is electrified, sparks can be generated between the carbon brush and the commutator due to change of the reversing current, and an included angle is formed between the commutator and the iron core, so that the generation of the reversing sparks can be reduced, reliable reversing is realized, and the service life of the carbon brush is prolonged. Radiating holes are formed in the position, close to the carbon brush, of the machine shell, so that radiating is facilitated.

The wire diameter and the middle diameter of the torsion spring are fixed with the number of turns, and the included angle between the two extension sections is matched with the positioning groove structure on the middle plate component, so that the hook-shaped structure end of the torsion spring has a certain deformation and initial pressure when contacting the bottom end of the carbon brush. The carbon brush is ground short in the use process of the motor, and the hook-shaped structure end of the torsion spring is always in contact with the carbon brush and keeps pressure.

Compared with the prior art, the utility model has the advantages that the utility model adopts the fixed brush box structure, thereby ensuring the constant reversing angle of the motor; and the torsion spring is adopted to apply pressure to the electric brush, so that the stability of the pressure of the carbon brush in the service life of the motor is ensured. The geometric central line of commutator segment and rotor core notch is usually aligned to original scheme, and there is certain deflection in this scheme commutator compartment groove and iron core open-ended circumferencial direction to realize reducing the switching-over spark, the effect of raising the efficiency. This scheme just increases heat dissipation breach at the part of casing to the carbon brush, improves the reliability of motor.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 is a schematic structural diagram of the micro-motor of the present invention.

Fig. 2 is an exploded view of the micro-motor of the present invention.

Fig. 3 is a cross-sectional view of the micro-motor of the present invention.

Figure 4 is a schematic diagram of the construction of the midplane assembly.

Fig. 5 is a schematic view of the structure of the rotor.

Fig. 6 is a schematic view of another angle of the rotor.

Fig. 7 is a schematic structural view of the torsion spring.

In the figure, 1 is a middle plate assembly, 2 is a brush box, 3 is a carbon brush, 4 is a torsion spring, 5 is a rear cover, 6 is a machine shell, 7 is an iron core, 8 is a commutator, and 9 is a rotating shaft.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the accompanying drawings and embodiments. It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. The terms "upper", "lower", "left", "right", "inner", "outer" and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Examples

The micro-motor comprises a rotor, a middle plate assembly 1 and a shell 6, wherein the middle plate assembly is provided with a carbon brush hole and a fixing groove, a brush box 2 and a carbon brush 3 are arranged in the carbon brush hole, the brush box is fixed on the middle plate assembly, the carbon brush slides in the brush box in a single direction, a torsion spring 4 is further arranged on the middle plate assembly, one end of the torsion spring is clamped into the fixing groove, the other end of the torsion spring is in contact with the carbon brush and pushes the carbon brush to be tightly pressed towards the direction of the rotor, heat dissipation holes are formed in the position of the carbon brush for installing the shell, as shown in figures 5-6, the rotor comprises an iron core 7, a commutator 8 and a rotating shaft 9, the carbon brush is tightly attached to the surface of the commutator, the iron core and the commutator are both installed on the rotating shaft, the radius of the center of any iron core opening and the radius of the heat dissipation holes of any commutator form an included angle larger than 0 degree, the center of the iron core opening and the center of the commutator groove are not on the same diameter, the center of the iron core opening and the center of the commutator groove form an included angle α, wherein the brush assembly is fixed in the brush box, the carbon brush box, the brush box only can slide along one direction of the brush box in one direction of the brush box, the center of the brush box is ensured, the center of the.

The micromotor is also provided with a rear cover 5 matched with the shell, and the middle plate component is fixed on the rear cover. By adopting the structure, the carbon brush on the middle plate component is fixed at the axial position of the motor.

As shown in FIG. 7, the torsion spring comprises a coil part and two extension parts connected with the coil, wherein the two extension parts are respectively positioned at the upper side and the lower side of the torsion spring, the included angle β is formed by the two extension parts of the torsion spring, the included angle β becomes smaller after the torsion spring is installed in the middle plate assembly, the included angle β is changed along with the abrasion of carbon brushes during the operation process of the motor, the pressure of the carbon brushes is always kept within an allowable range, the torsion spring adopts beryllium copper material, and for the convenience of installation, a hook-shaped structure is arranged on one extension part of the torsion spring, and the other extension part of the torsion spring is in a linear structure.

The line diameter D and the middle diameter D of the torsion spring are fixed with the number of turns, the included angle between the two extension sections is β, and the hook-shaped structure end of the torsion spring has certain deformation and initial pressure when contacting the bottom end of the carbon brush by matching with the positioning groove structure on the middle plate assembly.

It should be noted that the preferred embodiments of the present invention are described in the specification and the drawings, but the present invention can be realized in many different forms, and is not limited to the embodiments described in the specification, and these embodiments are not provided as additional limitations to the present invention, and are provided for the purpose of making the understanding of the disclosure of the present invention more thorough and complete. Moreover, the above technical features are combined with each other to form various embodiments which are not listed above, and all the embodiments are regarded as the scope of the present invention; further, modifications and variations will occur to those skilled in the art in light of the foregoing description, and it is intended to cover all such modifications and variations as fall within the true spirit and scope of the invention as defined by the appended claims.

Claims

1. A micro motor is characterized by comprising a rotor, a middle plate assembly and a shell, wherein a carbon brush hole and a fixing groove are formed in the middle plate assembly, a brush box and a carbon brush are arranged in the carbon brush hole, the carbon brush slides in the brush box in a single direction, a torsion spring is further arranged on the middle plate assembly, one end of the torsion spring is clamped in the fixing groove, and the other end of the torsion spring is in contact with the carbon brush and pushes the carbon brush to be compressed towards the rotor; the position of the shell where the carbon brush is installed is provided with a heat dissipation hole; the rotor comprises an iron core, a commutator and a rotating shaft, wherein the iron core and the commutator are both arranged on the rotating shaft, and the radius of the center of any iron core opening and the radius of the center of the notch of any commutator form an included angle larger than 0 degree.

2. The micro-machine of claim 1, further comprising a back cover coupled to the housing, wherein the middle plate assembly is secured to the back cover.

3. The micro-machine of claim 1, wherein the torsion spring comprises a coil portion and two extensions connected to the coil, the extensions being located on an upper side and a lower side of the torsion spring, respectively.

4. The micro-machine of claim 1, wherein said torsion spring is comprised of beryllium copper.

5. The micro-machine of claim 3, wherein one of the extension sections of the torsion spring is provided with a hook-shaped structure, and the other extension section is a linear structure.

6. The micro-machine of claim 1, wherein said brush box is secured to a midplane assembly.

7. The micro-machine of claim 1, wherein the carbon brushes are positioned against the commutator surface.