Ultra-low stiction torque transfer device

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement, wherein one of the pair of relatively rotatable members is rotatable and includes a plurality of cooling holes-aligned perpendicular to an axis of rotation of the rotatable member;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state, the O-ring having inner and outer aspects defined to respective sides of a plane bisecting the O-ring in a direction perpendicular to the web in the unextended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove with an inclined wall, the O-ring being received in the groove with the inner aspect contacting the inclined wall whereby to form a seal therebetween, the body member having a lip extending toward the web and over the groove so as to contact the O-ring along only the outer aspect thereof in the unextended state of the web, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having an annular generally-planar extensible web with an inner peripheral edge and an outer peripheral edge, an inner O-ring integrally formed along the inner peripheral edge, and an outer O-ring integrally formed along the outer peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state, the inner O-ring having an inner aspect and an outer aspect defined to respective sides of a first plane bisecting the inner O-ring in a direction perpendicular to the web in the unextended state, and the outer O-ring having an inner aspect and an outer aspect defined to respective sides of a second plane bisecting the outer O-ring in a direction perpendicular to the web in the unextended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having an inner groove with a first inclined wall and an outer groove with a second inclined wall, said inner and outer grooves have a spaced relationship, the inner O-ring being received in the inner groove with the inner aspect contacting the first inclined wall whereby to form a seal therebetween, the outer O-ring being received in the outer groove with the inner aspect contacting the second inclined wall whereby to form a seal therebetween, the body member having an inner lip extending toward the web and over the inner groove so as to contact the inner O-ring along only the outer aspect thereof in the unextended state of the web, the inner lip holding the inner O-ring in the inner groove while allowing the inner O-ring to rotate therein, and the body member having an outer lip extending toward the web and over the outer groove so as to contact the outer O-ring along only the outer aspect thereof in the unextended state of the web, the outer O-ring holding in the outer groove while allowing the outer O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove extending generally transverse to the web for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, the lip being configured to retain the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge such that a top surface of the web and an outer surface of the O-ring join along a curvilinear surface, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove extending generally transverse to the diaphragm web for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring consisting essentially entirely of elastomeric material being integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip integral with the body as a single piece therewith and extending toward the web and radially over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge arid an O-ring consisting essentially entirely of elastomeric material being integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, the lip being configured to retain the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring consisting essentially entirely of an elastomeric material integrally formed along the peripheral edge such that a top surface of the web and an outer surface of the O-ring join along a curvilinear surface, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the-peripheral edge and being substantially co-planar with the web, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip integral with the body as a single piece therewith and extending toward the web and radially over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge, the O-ring being substantially co-planar with the web, and the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, the lip being configured to retain the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring substantially co-planar with the web, the O-ring being integrally formed along the peripheral edge such that a top surface of the web and an outer surface of the O-ring join along a curvilinear surface, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, whereby to hold the O-ring in the groove while allowing the O-ring to sealingly move therein.

A torque transfer device comprising:

• a pair of relatively rotatable members adapted to transfer torque therebetween when urged into frictional engagement;
• a piston movable towards the rotatable members to selectively urge the rotatable members into frictional engagement;
• a diaphragm having a generally planar extensible web with a peripheral edge and an O-ring integrally formed along the peripheral edge, the web being extensible by fluid pressure from an unextended state to an extended state;
• and
• a body member supporting the diaphragm and being positioned relative to the piston such that the piston moves towards the rotatable members in the extended state of the web, the body member having a groove for receiving therein the O-ring of the diaphragm and a lip extending toward the web and over the groove so as to contact a portion of the O-ring, the lip being inclined at an acute angle relative to the groove for retaining the O-ring in the groove while allowing the O-ring to sealingly move therein.