阅读说明：本技术 一种基于表面织构的超声电机用增摩结构 (Ultrasonic motor friction increasing structure based on surface texture ) 是由 赵盖 雷浩 宋敬伏 余元豪 丁庆军 裘进浩 孙志峻 于 2019-12-05 设计创作，主要内容包括：本发明公开了一种基于表面织构的超声电机用增摩结构,包括摩擦材料基底,所述摩擦材料基底的材质为聚合物基复合材料,设置在超声电机的转子外端面,摩擦材料基底的表面设置有表面织构,表面织构的结构为微凸体或微凹坑的一种或两种,微凸体包括正六边形微凸体、方形微凸体、圆形微凸体,微凹坑包括正六边形微凹坑、方形微凹坑、圆形微凹坑。本发明在超声电机的摩擦材料进行表面织构,在干摩擦的条件下,表面织构的存在会增大摩擦系数,从而增大超声电机的输出力矩；表面织构形成的空隙能有效的捕获并容纳磨屑,减少了磨粒磨损和犁沟,提高了超声电机的使用寿命。(The invention discloses a friction increasing structure for an ultrasonic motor based on a surface texture, which comprises a friction material substrate, wherein the friction material substrate is made of a polymer matrix composite material and is arranged on the outer end face of a rotor of the ultrasonic motor, the surface texture is arranged on the surface of the friction material substrate, the structure of the surface texture is one or two of a micro-convex body and a micro-concave pit, the micro-convex body comprises a regular hexagon micro-convex body, a square micro-convex body and a round micro-convex body, and the micro-concave pit comprises a regular hexagon micro-concave pit, a square micro-concave pit and a round micro-concave pit. According to the invention, the friction material of the ultrasonic motor is subjected to surface texture, and the friction coefficient can be increased due to the surface texture under the condition of dry friction, so that the output torque of the ultrasonic motor is increased; the gaps formed by the surface texture can effectively capture and contain abrasive dust, abrasive wear and furrowing are reduced, and the service life of the ultrasonic motor is prolonged.)

1. The utility model provides an ultrasonic motor is with increasing structure of rubbing based on surface texture which characterized in that: the friction material substrate is made of a polymer matrix composite material and is arranged on the outer end face of a rotor of an ultrasonic motor, the surface of the friction material substrate is provided with a surface texture, the structure of the surface texture is one or two of a micro-convex body and a micro-concave pit, the micro-convex body comprises a regular hexagon micro-convex body, a square micro-convex body and a round micro-convex body, and the micro-concave pit comprises a regular hexagon micro-concave pit, a square micro-concave pit and a round micro-concave pit.

2. The surface texture based ultrasonic motor friction increasing structure according to claim 1, characterized in that: the friction material substrate is made of polytetrafluoroethylene base, polyimide base, polyether ether ketone base, polyphenylene sulfide base or phenolic resin base composite material.

3. The surface texture based ultrasonic motor friction increasing structure according to claim 2, characterized in that: the friction material substrate is made of a graphene modified polyimide composite material.

4. The surface texture based ultrasonic motor friction increasing structure according to claim 1, characterized in that: the radius of the circular micro-convex bodies and the circular micro-concave pits is 100-200 mu m.

5. The surface texture based ultrasonic motor friction increasing structure according to claim 1, characterized in that: the side length of the square micro-convex body and the square micro-concave pit is 100-200 mu m.

6. The surface texture based ultrasonic motor friction increasing structure according to claim 1, characterized in that: the side length of the regular hexagonal micro-convex body and the regular hexagonal micro-concave pit is 100-200 mu m.

7. The surface texture based ultrasonic motor friction increasing structure according to claim 1, characterized in that: the area density of the surface texture is 20-50%.

Technical Field

The invention relates to the technical field of ultrasonic motors, in particular to a friction increasing structure for an ultrasonic motor, which can improve the output torque of the ultrasonic motor and prolong the service life of the ultrasonic motor.

Background

The ultrasonic motor is a novel micro special motor which is rapidly developed in the 80 th of the 20 th century and has special application, and the working principle of the ultrasonic motor is that the inverse piezoelectric effect of a piezoelectric material is utilized to excite the micro amplitude vibration of an elastic body (a stator) in an ultrasonic frequency band, and the friction action between the stator and a rotor is utilized to drive the rotor to move. Since the ultrasonic motor transmits power through a friction interface, the friction characteristics between the stator and the rotor determine the output performance of the motor. The output torque of the ultrasonic motor can be increased along with the increase of the friction coefficient within a certain range according to the operation characteristics of the ultrasonic motor. At present, the friction material between the stator and the rotor is generally polytetrafluoroethylene-based composite material or polyimide-based composite material, and the friction coefficient is low, so that the output torque of the ultrasonic motor is insufficient. The abrasion of the ultrasonic motor friction pair mainly comprises abrasive wear and fatigue wear, the abrasion can finally cause the damage of a friction interface, and the service life of the motor is shortened and even the motor fails. How to reduce the abrasion and improve the service life of the ultrasonic motor is also an urgent problem to be solved.

Disclosure of Invention

The invention aims to provide a friction increasing structure for an ultrasonic motor based on surface texture, and aims to solve the problems that the ultrasonic motor in the prior art is insufficient in output torque and short in service life.

In order to achieve the purpose, the invention adopts the technical scheme that:

the friction increasing structure for the ultrasonic motor based on the surface texture comprises a friction material substrate, wherein the friction material substrate is made of a polymer matrix composite material and is arranged on the outer end face of a rotor of the ultrasonic motor, the surface texture is arranged on the surface of the friction material substrate, the structure of the surface texture is one or two of a micro-convex body and a micro-concave pit, the micro-convex body comprises a regular hexagon micro-convex body, a square micro-convex body and a round micro-convex body, and the micro-concave pit comprises a regular hexagon micro-concave pit, a square micro-concave pit and a round micro-concave pit.

The friction material substrate is made of polytetrafluoroethylene base, polyimide base, polyether ether ketone base, polyphenylene sulfide base or phenolic resin base composite material. Preferably, the friction material substrate is made of a graphene modified polyimide composite material.

Preferably, the radius of the circular micro-convex body and the circular micro-concave pit is 100-200 μm.

Preferably, the side length of the square microprotrusions and the square micropits is 100-200 μm.

Preferably, the side length of the regular hexagonal micro-convex body and the regular hexagonal micro-concave pit is 100-200 mu m.

Preferably, the area density of the surface texture is 20-50%.

Has the advantages that: compared with the prior art, the invention has the following advantages:

(1) according to the invention, the friction material of the ultrasonic motor is subjected to surface texture, and the friction coefficient can be increased due to the surface texture under the condition of dry friction, so that the output torque of the ultrasonic motor is increased;

(2) the gaps formed by the surface texture can effectively capture and contain abrasive dust, abrasive wear and furrowing are reduced, and the service life of the ultrasonic motor is prolonged.

Drawings

FIG. 1 is a schematic illustration of a prior art ultrasonic motor friction material without surface texturing;

fig. 2 is a schematic diagram of a friction-increasing structure for an ultrasonic motor based on a surface texture, wherein the surface texture is in the shape of a circular convex body;

FIG. 3 is an enlarged view of a portion A of FIG. 2;

FIG. 4 is a pictorial view of a rotor equipped with a friction enhancing structure for a surface texture based ultrasonic motor of the present invention;

in the figure, 1-friction material substrate, 2-surface texture, 3-rotor.

Detailed Description

The invention is further explained below with reference to the drawings.

As shown in fig. 1, the surface of the friction material used in the ultrasonic motor of the related art is smooth.

Based on the friction driving mechanism of the ultrasonic motor, a friction increasing interface is required to maintain larger output torque, so that the invention provides a friction increasing structure for the ultrasonic motor based on surface texture, the surface of a friction material is prepared into a series of surface textures with different forms by methods of laser melting, ultrasonic fine processing and the like, and the surface textures are textured friction surfaces with friction increasing effect to improve the friction coefficient between friction pairs, thereby being capable of improving the output torque of the ultrasonic motor. Due to the fact that the gaps in the surface texture can well capture and contain abrasive dust and abrasive grains generated by abrasion, the abrasion rate can be reduced while the friction coefficient is improved, and the service life of the ultrasonic motor is prolonged.

As shown in fig. 2, the friction increasing structure for the ultrasonic motor based on the surface texture comprises a friction material substrate 1, wherein the friction material substrate 1 is made of a polymer matrix composite material and is arranged on the outer end face of a rotor of the ultrasonic motor, the surface texture 2 is arranged on the surface of the friction material substrate 1, the surface texture structure is one or two of a micro-convex body and a micro-concave pit, the micro-convex body comprises a regular hexagonal micro-convex body, a square micro-convex body and a round micro-convex body, and the micro-concave pit comprises a regular hexagonal micro-concave pit, a square micro-concave pit and a round micro-concave pit.

The friction material substrate 1 is made of polytetrafluoroethylene, polyimide, polyether ether ketone, polyphenylene sulfide or phenolic resin based composite materials. In the invention, the material of the friction material substrate is preferably a graphene modified polyimide composite material, which is disclosed in the Chinese patent with the publication number of CN105820567A, which was previously applied by the applicant of the invention.

Wherein the radius of the round micro-convex body and the round micro-concave pit is 100-200 μm, the side length of the square micro-convex body and the square micro-concave pit is 100-200 μm, and the side length of the regular hexagon micro-convex body and the regular hexagon micro-concave pit is 100-200 μm.

Wherein the area density of the surface texture is 20-50%, namely the area of the surface texture accounts for 20-50% of the surface area of the friction material substrate.

The present invention is further illustrated by the following specific examples.