Pulley structure

Patent metadata

Field	Value
Publication number	US-11668386-B2
Application number	US-201816603304-A
Country	US
Kind code	B2
Filing date	Apr 17, 2018
Priority date	Apr 19, 2017
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

A pulley structure may be equipped with an outer rotating body, an inner rotating body, and a coil spring provided between the outer rotating body and the inner rotating body. The coil spring is configured so as to undergo torsional deformation in a diameter-expanding or a diameter-contracting direction, thereby engaging the outer rotating body and the inner rotating body and transmitting torque, and to undergo torsional deformation in the direction opposite the direction in which torque is transmitted, thereby entering a disengaged state in which the coil spring slides with the outer rotating body or the inner rotating body, thus interrupting the transmission of torque. The number of windings of the coil spring is in a range between [M-0.125] and M (both inclusive), where M is a natural number.

First claim

The invention claimed is:

1. A pulley structure comprising:
a cylindrical outer rotating body around which a belt is to be wound;
an inner rotating body provided on a radial inside of the outer rotating body and relatively rotatable with respect to the outer rotating body around a common rotation axis with the outer rotating body; and
a coil spring provided between the outer rotating body and the inner rotating body and compressed in an axial direction along the common rotation axis,
wherein the coil spring is configured to be engaged with the outer rotating body and the inner rotating body due to torsional deformation in a diameter expansion or diameter reduction direction to transmit torque between the outer rotating body and the inner rotating body, and is configured to come into a disengaged state in which the coil spring slides with respect to the outer rotating body or the inner rotating body due to torsional deformation in a direction opposite to the direction when the torque is transmitted, so as to block the transmission of torque between the outer rotating body and the inner rotating body, and
wherein the coil spring has a number of windings within a range of M-0.669 or more and less than M, where M is a natural number.

2. The pulley structure according to claim 1 , wherein the coil spring has a torsional torque, which is set to be 1 N·m or more and 10 N·m or less when the coil spring is in the disengaged state.

3. The pulley structure according to claim 1 , wherein the coil spring has a torsional torque, which is set to be 1 N·m or more and 10 N·m or less when the coil spring is in the disengaged state.

Assignees

• Mitsuboshi Belting Ltd

Inventors

• Shimamura Hayato
• Imai Katsuya
• Dan Ryosuke
• Morimoto Takashi

Classifications

• F16F2238/024

  torsional · CPC title

• F16F15/1216 Primary

  Torsional springs, e.g. torsion bar or torsionally-loaded coil springs · CPC title

• F16D41/206

  having axially adjacent coils, e.g. helical wrap-springs · CPC title

• F16F2228/001

  Specific functional characteristics in numerical form or in the form of equations · CPC title

• F16H2055/366

  with means providing resilience or vibration damping · CPC title