Alternator pulley

Abstract

An alternator pulley includes a driving member driven and rotated via a belt from an output shaft of an engine. A driving member is disposed on an inner surface of the driving member and a one-way clutch is interposed between the driving and driven member. The one-way clutch includes rollers capable of rolling in a locked side direction along which a rotating power of the driving member is transmitted to the driven member or a free side direction along which the rotating powder is interrupted. Depending on a relative speed difference between the driving member and the driven member, the rollers are biased for pressing in the locked side direction and a torque value of the pressing is set preferably to less than 4 Nm.

1. An alternator pulley comprising:
 an annular driving member having an inner side and an outer side, said annular driving member having a first center of rotation, said driving member having a first rotation speed and a second rotation speed, said first rotation speed being substantially greater than said second rotation speed; 
 a belt disposed on said outer side of said driving member; 
 a driven member disposed on said inner side of said driving member, said driven member having an inner surface and an outer surface, said driven member having a second center of rotation, said first center of rotation being substantially coincident with said second center of rotation; and 
 a one-way clutch being disposed between said inner side of said driving member and said outer surface of said driven member, said one-way clutch including:
 an inner race being disposed on an outer surface of said driven member, said inner race having an inner side and an outer side, said inner side of said inner race contacting said outer surface of said driven member, said outer side of said inner race including a plurality of cam surfaces; 
 
 a retainer disposed between said outer surface of said inner race and said inner side of said driving member, said retainer including a plurality of pockets, each pocket including a first wedge-shaped side and a second wedge-shaped side, each first wedge-shaped side being substantially wider than each second wedge-shaped side, each wedge-shaped side defining a wedge element, each wedge element having a first surface disposed within a respective pocket and a second annular surface adjacent to said inner side of said driving member;
 a plurality of pressing members, each pocket including a pressing member, each pressing member disposed adjacent to a respective first wedge-shaped side of a pocket; and 
 a plurality of rollers, each pocket including a roller biased by a respective pressing member, said rollers being in one of a locked state and a free flowing state, said locked state occurring when a respective pressing member biases a respective roller against a respective second wedge-shaped side of a pocket, said free flowing state occurring when a respective pressing member biases a respective roller against a respective first wedge-shaped side of a pocket, 
 
 whereby during said first rotation speed, each roller is in said locked state, and during said second rotation speed, each roller is in said free flowing state and said driven member continues rotation due to inertia and said rollers which in turn substantially increases power generation efficiency during said second rotation speed. 
 
     
     
       2. The alternator pulley of  claim 1 , wherein each pressing member has a torque value, each torque value is less than 4 N·m. 
     
     
       3. The alternator pulley of  claim 1 , each pressing member has a torque value, each torque value is a value obtained by multiplying a radius taken from an axis of said inner race to each of said pressing members by a pressing force of said pressing member. 
     
     
       4. The alternator pulley of  claim 3 , wherein said pressing members are resilient members which are received in recesses continuous with said pockets, respectively, and which press said rollers toward said locked side direction, respectively. 
     
     
       5. The alternator pulley of  claim 4 , wherein said resilient members are disposed in positions where they press inner sides of said rollers toward said locked side direction. 
     
     
       6. The alternator pulley of  claim 5 , further comprising receiving members each of which is engaged with one end of each of said resilient members and bears against each of peripheral surfaces of said rollers. 
     
     
       7. The alternator pulley of  claim 1 , further comprising rolling bearings mounted on axially opposite sides of said one-way clutch between said driving member and said driven member. 
     
     
       8. The alternator pulley of claim 1, wherein an outer side of a respective pressing member contacts a middle portion of a corresponding roller such that the pressing members bear against axial centers of the rollers.