JP3037951U - Ultrasonic motor rotor pressure spring - Google Patents

Abstract

(57) [Abstract] [Object] The present invention relates to an apparatus in which a rotor of an ultrasonic motor is integrally formed with a spring having a special shape. [Structure] A disk-shaped spring 5 is integrally formed on the rotor 2,
A boss 6 is provided at the center of the spring 5 and the shaft 11 is press-fitted therein.

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention relates to improvement of an ultrasonic motor.

[0002]

[Prior art]

 Conventionally, coil springs, disc springs, etc. were used as a means to pressurize the rotor of the ultrasonic motor stator, but a large space is required due to its structure, and rattling is likely to occur in preventing rotation of the rotor and shaft. It was On the other hand, the rotor pressure spring applied by the present applicant (actual application No. 4-474777) has a large spring constant, so that the pressing force is likely to fluctuate even with a slight dimensional change.

[0003]

[Problems to be solved by the device]

 Except for its drawbacks, the present proposal aims to develop an ultrasonic motor that is housed in a minimum space and has stable pressing force and a rotor and a shaft that are firmly fixed.

[0004]

[Means for Solving the Problems]

 Now, the solution means will be described with reference to the drawings. (A) The spring 5 described in the claims is formed integrally with the rotor 2, and the boss 6 is provided at the center of the spring 5. (B) The shaft 11 is press-fitted into the boss 6, or the shaft is knurled and press-fitted. If the rotor 2, spring 5, and boss 6 are made of the same material, they can be made by cutting or pressing. If they are different materials, each member is made by welding, bonding, pressure welding, press fitting, etc. You can do it.

[0005]

[Action]

 Since the present invention has the structure as described above, when the rotor 2 is pressed against the stator 1, when the boss 6 is pressed through the bearing 9, the spring 5 is elastically deformed as shown in FIG. 2 (b). Transforms into.

[0006]

【Example】

 (1) As shown in FIGS. 2A and 2B, in the spring 5, the outer peripheral portion 5A from the outer peripheral point P1 to the intermediate point P2 has a parallel plate thickness, and the intermediate point P2 to the inner peripheral point P3 (boss). By making the shape such that the plate thickness increases toward the outer circumference), the amount of deflection S can be increased by minimizing the stress acting on the member. (2) As shown in FIG. 3, when the outer peripheral point P1 has a plate thickness t1, the intermediate point P2 has a plate thickness t2, and the inner peripheral point P3 has a thickness t3, t2 <t1 <t3. If formed so that the stress acting on the member can be made substantially uniform, and as a result, the amount of deflection can be increased. (3) As shown in FIG. 4, the spring 5 can obtain a larger amount of deflection by forming the concentric circular cross section into a plurality of corrugations. (4) As shown in FIG. 5, the spring 5 has a large amount of deflection by forming a plurality of concentric grooves.

[0007]

[Effect of the invention]

 Therefore, it is a compact, low-cost, and highly reliable ultrasonic motor.

[Brief description of the drawings]

FIG. 1 is a sectional view of an ultrasonic motor according to the present invention.

FIG. 2 (a) is a cross-sectional view in which a spring 5, a rotor 2 and a boss 6 of the present invention are integrally formed.

FIG.

FIG.

FIG. 5 is a cross-sectional view in which a spring 5, a rotor 2 and a boss 6 are integrally formed according to another embodiment of the present invention.

[Explanation of symbols]

 1 Stator 2 Rotor 3 Elastic Body 4 Piezoelectric Body 5 Spring 6 Boss

[Procedure amendment]

[Submission date] December 11, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims for utility model registration

[Correction method] Change

[Correction contents]

[Utility model registration claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2 (a) Spring 5, rotor 2 and boss 6 of the present invention
Sectional drawing which was integrally formed. (B) A sectional view of the spring 5 of the present invention when it is under pressure.

Claims (4)

[Utility model registration claims] 1. An ultrasonic motor comprising: a stator 1 in which a plurality of piezoelectric elements 4 are fixedly arranged on an elastic body 3; and a rotor 2 in pressure contact with the elastic body surface of the stator 1. Reference numeral 5 is a disc-shaped rotor of an ultrasonic motor in which the outer peripheral portion 5A has a parallel plate thickness and the inner peripheral portion 5B has a plate thickness increasing toward the circumference. Pressure spring. 2. The spring 5 has a disc shape, and the thickness of the outer peripheral portion 5A decreases from the outer periphery toward the inner periphery, and the thickness of the inner peripheral portion 5B increases toward the inner periphery. The rotor pressure spring of the ultrasonic motor that is operating. 3. The rotor pressure spring for an ultrasonic motor according to claim 1, wherein the spring 5 is formed in a plurality of concentric circular waveforms. 4. A rotor pressure spring for an ultrasonic motor according to claim 1, wherein the spring 5 has a plurality of concentric circular grooves.