Pulley device with embedded unidirectional clutch

Patent metadata

Field	Value
Publication number	US-2016169302-A1
Application number	US-201414907347-A
Country	US
Kind code	A1
Filing date	Jun 25, 2014
Priority date	Jul 25, 2013
Publication date	Jun 16, 2016
Grant date	—

Abstract

The present invention addresses the problem of implementing a pulley device with an embedded unidirectional clutch, with which the influence of auxiliary automobile machinery on a rotary shaft due to fluctuations in the rotation of the engine can be sufficiently reduced. A sleeve ( 1 b ) is configured from an inner-diameter-side sleeve ( 24 ) and an outer-diameter-side sleeve ( 25 ), a unidirectional clutch ( 3 ) is provided between the outer-diameter-side sleeve ( 25 ) and a pulley ( 2 ), and a coiled torsion spring ( 18 a ) capable of transmitting torque between the inner-diameter-side sleeve ( 24 ) and the outer-diameter-side sleeve ( 25 ) is provided between these members ( 24, 25 ). When the rotational speed of the pulley ( 2 ) becomes slower than the rotational speed of the outer-diameter-side sleeve ( 25 ), the inner-diameter-side sleeve ( 24 ) and the outer-diameter-side sleeve ( 25 ) rotate relative to one another due to the elastic force of the coiled torsion spring ( 18 a ), until the elastic force of the coiled torsion spring ( 18 a ) is released, after which the unidirectional clutch ( 3 ) becomes incapable of transmitting torque between the pulley ( 2 ) and the outer-diameter-side sleeve ( 25 ).

First claim

1 . A pulley device with embedded unidirectional clutch, comprising:
a sleeve capable of being fastened to a rotating shaft; a pulley arranged around the sleeve and being concentric with the sleeve; a unidirectional clutch provided between the outer-circumferential surface of the sleeve and the inner-circumferential surface of the pulley, and transmitting torque between the pulley and the sleeve only when the pulley rotates in a specified direction relative to the sleeve; and a pair of support bearings provided between the outer-circumferential surface of the sleeve and the inner-circumferential surface of the pulley, and making possible relative rotation between the sleeve and the pulley; wherein
the sleeve comprises an inner-diameter-side sleeve fastened around the rotating shaft, and an outer-diameter-side sleeve arranged around the inner-diameter-side sleeve so as to be concentric with and rotate relative to the inner-diameter-side sleeve; and
when the pulley is in a state of rotating relative to the outer-diameter-side sleeve in a direction opposite the specified direction, the rotational torque that is required for the inner-diameter-side sleeve to rotate relative to the outer-diameter-side sleeve is less than the engagement release torque that is required for engagement of the unidirectional clutch to be released.

2 . A pulley device with embedded unidirectional clutch, comprising:
a sleeve capable of being fastened to a rotating shaft; a pulley arranged around the sleeve and being concentric with the sleeve; a unidirectional clutch provided between the outer-circumferential surface of the sleeve and the inner-circumferential surface of the pulley, and transmitting torque between the pulley and the sleeve only when the pulley rotates in a specified direction relative to the sleeve; and a pair of support bearings provided between the outer-circumferential surface of the sleeve and the inner-circumferential surface of the pulley, and making possible relative rotation between the sleeve and the pulley; wherein
the sleeve comprises an inner-diameter-side sleeve fastened around the rotating shaft, and an outer-diameter-side sleeve arranged around the inner-diameter-side sleeve so as to be concentric with and rotate relative to the inner-diameter-side sleeve;
the unidirectional clutch is provided between the outer-circumferential surface of the outer-diameter-side sleeve and the inner-circumferential surface of the pulley;
the pair of support bearings are respectively arranged between the outer-circumferential surface of the inner-diameter-side sleeve and the inner-circumferential surface of the pulley, and between the outer-circumferential surface of the outer-diameter-side sleeve and the inner-circumferential surface of the pulley;
an elastic member is further provided between the inner-diameter-side sleeve and the outer-diameter-side sleeve, and when elastically deformed due to the relative rotation of these members, torque can be transmitted between these members; and
when the pulley is in a state of rotating relative to the outer-diameter-side sleeve in a direction opposite the specified direction, the inner-diameter-side sleeve and the outer-diameter-side sleeve rotate relative to each other due to the elastic force of the elastic member until the elastic force of the elastic member is released.

3 . The pulley device with embedded unidirectional clutch according to claim 2 , wherein a bearing is provided between the inner-circumferential surface of the outer-diameter-side sleeve and the outer-circumferential surface of the inner-diameter-side sleeve.

4 . The pulley device with embedded unidirectional clutch according to claim 2 , wherein
the elastic member is a coiled torsion spring; and an outer-diameter-side engagement section that is capable of engaging with one end of the coiled torsion spring is provided in the outer-diameter-side sleeve, and an inner-diameter-side engagement section that is capable of engaging with the other end of the coiled torsion spring is provided in the inner-diameter-side sleeve.

5 . The pulley device with embedded unidirectional clutch according to claim 1 , wherein
the unidirectional clutch comprises:
a cylindrical surface that is the inner-circumferential surface of the pulley, or is provided on the inner-circumferential surface of a clutch outer ring that is fitted in the pulley with an interference fit;
a cam surface that is formed on the outer-circumferential surface of the outer-diameter-side sleeve, or formed on the outer-circumferential surface of a clutch inner ring that is fitted around the outer-circumferential surface of the outer-diameter-side sleeve with an interference fit; and
plural locking members that are provided between the cam surface and the cylindrical surface.

6 . The pulley device with embedded unidirectional clutch according to claim 2 , wherein
the unidirectional clutch comprises:
a cylindrical surface that is the inner-circumferential surface of the pulley, or is provided on the inner-circumferential surface of a clutch outer ring that is fitted in the pulley with an interference fit;
a cam surface that is formed on the outer-circumferential surface of the outer-diameter-side sleeve, or formed on the outer-circumferential surface of a clutch inner ring that is fitted around the outer-circumferential surface of the outer-diameter-side sleeve with an interference fit; and
plural locking members that are provided between the cam surface and the cylindrical surface.

Assignees

• Nsk Ltd

Inventors

• Mori Hirofumi

Classifications

• F16D2041/0605

  Spring details · CPC title

• F16H7/0827

  for disconnecting the drive · CPC title

• F16H55/36 Primary

  Pulleys (with features essential for adjustment F16H55/52) · CPC title

• F16D47/04 Primary

  of which at least one is a freewheel (F16D47/02, F16D47/06 take precedence; freewheels combined with a clutch to lock the driving and driven members of the freewheel F16D41/04, F16D41/26) · CPC title

• F16D41/064

  the intermediate members wedging by rolling and having a circular cross-section, e.g. balls (F16D41/061 takes precedence) · CPC title