VIBRATION ACTUATOR

• US 20140035397A1
• Filed: 07/30/2013
• Published: 02/06/2014
• Est. Priority Date: 07/31/2012
• Status: Active Grant

• Current Assignee: Nidec Copal Corporation (Nidec Corporation)
• Original Assignee: Nidec Copal Corporation (Nidec Corporation)
• Inventors: ENDO, Masaya, TONOGAI, Yoshihide
• Granted Patent: US 9,692,286 B2
• Time in Patent Office: Days
• US Class Current: 310/30
• CPC Class Codes: H02K 33/16 with polarised armatures moving in alternate directions by reversal or energisation of a single coil system
• CPC Class Codes: H02K 33/18 with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets

Abstract

A first weight portion of a vibration actuator includes an inner-side enlarged portion that protrudes from an end portion of a solid head in a direction of a vibration axis and that is inserted into an opening portion extending within a first compression coil spring along the direction of the vibration axis. An outer peripheral surface of the inner-side enlarged portion becomes continuously smaller in diameter from a base end towards a free end, with the vibration axis being the center of the diameter. That is, the inner-side enlarged portion has the shape of a truncated cone. The inner-side enlarged portion is inserted into the opening portion of the first compression coil spring and the opening portion is utilized to change the length of the inner-side enlarged portion in the direction of the vibration axis, thereby changing the mass of the first weight portion.

Claims

1. A vibration actuator in which a magnet vibrates linearly in a housing along a vibration axis as a result of cooperation of a coil and the magnet, the vibration actuator comprising:

the housing;

the coil that is disposed in the housing;

the magnet that is surrounded by the coil; and

a weight that vibrates together with the magnet along the vibration axis, the weight including a weight body portion and an inner-side enlarged portion, the weight body portion being urged by a compression coil spring disposed along the vibration axis, the inner-side enlarged portion having an outer peripheral surface, protruding from the weight body portion in a direction of the vibration axis, and being inserted into an opening portion extending within the compression coil spring along the direction of the vibration axis,

wherein the outer peripheral surface of the inner-side enlarged portion becomes smaller in diameter from a base end towards a free end, the vibration axis being a center of the diameter.

2. The vibration actuator according to claim 1, wherein the weight further includes an outer-side enlarged portion that protrudes from the weight body portion at an outer side of the compression coil spring in the direction of the vibration axis.

3. The vibration actuator according to claim 2, wherein the outer-side enlarged portion has an inner peripheral surface that becomes larger in diameter from a base end towards a free end, the vibration axis being a center of the diameter, the inner peripheral surface facing the compression coil spring.

4. A vibration actuator in which a magnet vibrates linearly in a housing along a vibration axis as a result of cooperation of a coil and the magnet, the vibration actuator comprising:

the housing;

the coil that is disposed in the housing;

the magnet that is surrounded by the coil; and

a weight that vibrates together with the magnet along the vibration axis, the weight including a weight body portion and an inner-side enlarged portion, the weight body portion being urged by a compression coil spring disposed along the vibration axis, the inner-side enlarged portion having an outer peripheral surface, protruding from the weight body portion in a direction of the vibration axis, and being inserted into an opening portion extending within the compression coil spring along the direction of the vibration axis,

wherein the outer peripheral surface of the inner-side enlarged portion is smaller in diameter at a free end side than at a base end side, the vibration axis being a center of the diameter.