One-way clutch apparatus

Abstract

A one-way clutch apparatus comprising a driving member having a plurality of recesses, a corresponding plurality of biasing members disposed in the recess, a corresponding number of keys or struts disposed over the biasing members in the recesses, and a driven member having a plurality of key-engaging notches formed circumferentially about an inside surface. Each of the keys includes a pair of laterally protruding arm portions and each of the arm portions has a ramp formed thereon which acts as a relief to allow the inside surface of the driven member to be placed to close proximate relationship with the inside surface of a driving member and to overlay portions of the recess. The overlaying enables the driven member to damp or otherwise limit the movement of a back end portion of each key when the driving member is moved in either a free-wheeling direction or driving direction, while the ramp portions allow a front end portion of the key to be urged outwardly without any portion of the arm portion interfering with the inside surface of the driven member overlaying portions of each recess. The one-way clutch apparatus is not as dependent upon a copious and continuous supply of lubricant to damp unwanted movement of the key as prior art developed one-way clutch systems.

Description

TECHNICAL FIELDThis invention relates to clutches, and more particularly to a one-way clutch apparatus.DISCUSSIONClutches are used in a wide variety of applications to selectively couple power from an input member, such as a driving disk or plate, to a second independently rotatable member such as a driven plate or disk. In some applications, it is further desirable to incorporate a clutch which allows for rotational movement of the driving member in a second rotational direction in which no clutch engagement occurs, and therefore in which no rotation of the driven member occurs. Such clutches are commonly referred to as "one-way" clutches. With a one-way clutch, when a driving member is rotated in a first direction, the clutch causes engagement of the driving member with an external driven member. When the driving member is rotated in a second rotational direction opposite to that of the first rotational direction, the clutch releases the driven member from engagement with the driv...

AI Technical Summary

Benefits of technology

When the driving member is rotated in a first rotational direction, at some point during rotational movement thereof the key engaging portion moves directly over the key in the carrier plate. A first end portion of the key is urged into engagement with the key engaging portion in the driving member by the force of the biasing means, which in the preferred embodiment is in the form of a coil spring operably associated with the key. Engagement of the first end portion of the key in the key engaging portion of the driving member causes the carrier plate to begin moving rotationally with the driving member in the first rotational direction. As the key (and carrier plate) is moved rotationally to a position over the key engaging portion of the driven member the biasing force of the spring causes further rotational movement of the key itself such that a second end portion of the key engages or "drops into" engagement with the key engaging portion in the driven member. The driving member, carrier plate and driven member then all rotate in the first rotational direction with the key positively coupling the driving action of the driving member to the driven member.

The alternative embodiment just described above thus allows two concentrically disposed ring members such as annular gears to be driven together when one or the other is driven in one direction, and to be drivingly uncoupled when one or the other is rotated in the opposite rotational direction.

To allow the above-described close placement of portions of the surface of the driven member relative to the arms of the key, the arms of the key are formed with ramp portions thereon to provide a degree of relief to the arm portions. This degree of relief enables a front end portion of the key to be urged outwardly by a biasing member, such as a spring, and to engage a recess in the driven member when the driving member is rotated in a driving direction (i.e., a direction wherein the key will engage the driven member and drive the driven member rotatably therewith). The ramp portions formed on the arms of the key provide the needed clearance between the arm portions and the portions of the surface of the driven member which would otherwise interfere with the movement of the key or enough for the ramp portions. The ramp portions formed on the arms of the key thus allow the key to be rotated a sufficient degree to engage a driven member without interfering with one or more surface portions of the driven member disposed closely adjacent the driving member, which limits the movement of the back end portion of the key. In this manner, the key is "damped" by the closely positioned surface portions of the driven member. This enables the key to operate in a clutch being driven at a very high rpm, such as 5000 rpm or above. This arrangement further provides a means by which undesirable movement of the key can be "damped" without completely flooding the areas adjacent the key with a lubricating fluid. Thus, the clutch apparatus is even less dependent upon a copious and continuous supply of lubrication to the key and the surface areas which it engages during driving operation.

Problems solved by technology

This lubrication requirement becomes more difficult to satisfy as the transmission or other apparatus within which the one-way clutch is disposed is oriented in different angles, such as when a vehicle or aircraft associated with the transmission incorporating the one-way clutch changes its attitude relative to the earth's surface.

In such instances there may be momentary lapses of lubrication to the notches wherein the struts are housed.

These lapses, in some extreme instances, could adversely impact the wear of the one-way clutch.

Since the key is not physically pivotally secured to the member upon which it rests, the entire key is free to "lift", sometimes to a relatively large degree, which in turn might cause undesirable wear in the driven member positioned closely adjacent the key.

Such wear might occur if, for example, the back end of the key (i.e., the end opposite to that which engages the driven member) lifts significantly to contact a surface of the driven member when the driven member is being rotated in a free-wheeling direction.

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