Bi-directional friction clutch

Abstract

A clutch includes an input, an output, first and second control disks, and a control. The output and the input may be releasably coupled. The first control disk may be positioned between the input and the output. The first control disk and second control disk may be coupled and the output may be moveable between the control disks. The control may apply a torque to the second control disk, establishing a relative rotation between the output and the first control disk and decoupling the output and input.

What is claimed is: 
     
         1 . A clutch comprising:
 an input comprising a first friction surface,   an output comprising a second friction surface, the input and the output being releasably coupled by contact between the first friction surface and second friction surface,   a first control disk between the input and the output,   a second control disk, the first control disk and the second control disk being coupled, the output being moveable between the first control disk and the second control disk, and   a control that applies a torque to the second control disk to establish relative rotation between the output and the first control disk and that decouples the output and input.   
     
     
         2 . The clutch of  claim 1 , comprising:
 a groove in the output,   a groove in the first control disk, the groove in the output and the groove in the first control disk defining a pocket having a radius of curvature, and   a roller in the pocket, the roller having a radius of curvature smaller than the radius of curvature of the pocket.   
     
     
         3 . The clutch of  claim 1 , wherein the first control disk and the second control disk are coupled to rotate at the same angular speed. 
     
     
         4 . The clutch of  claim 3 , wherein the output comprises an opening and the clutch comprises a protrusion that extends through the opening and couples the first and second control disks. 
     
     
         5 . The clutch of  claim 4 , wherein the protrusion and the opening define a gap that limits relative rotation between the output and the first control disk. 
     
     
         6 . The clutch of  claim 5 , wherein the gap limits relative rotation between the output and the first control disk to not more than 0.8 degrees. 
     
     
         7 . The clutch of  claim 5 , wherein the output has a center and wherein the gap has a width of 0.027 inches for every inch that the gap is spaced from the center of the output. 
     
     
         8 . The clutch of  claim 4  comprising multiple protrusions that extend through multiple openings in the output and that couple the first and second control disks. 
     
     
         9 . The clutch of  claim 8 , wherein the output has a center and wherein the openings are equally spaced from the center of the output. 
     
     
         10 . The clutch of  claim 4  comprising a spring between the output and the second control disk that centers the protrusion in the opening. 
     
     
         11 . The clutch of  claim 4  comprising a spring that biases the output and the input toward each other and centers the protrusion in the opening. 
     
     
         12 . A method comprising:
 providing an input with a first friction surface and an output with a second friction surface, the input and the output being releasably coupled by contact between the first friction surface and second friction surface,   providing a first control disk and a second control disk, the first control disk and the second control disk being coupled, the first control disk being located between the input and the output, the output being moveable between the first control disk and the second control disk,   applying a torque to the second control disk to establish relative rotation between the output and the first control disk and decouple the output and input.   
     
     
         13 . The method of  claim 12 , comprising
 providing a groove in the output,   providing a groove in the first control disk, the groove in the output and the groove in the first control disk defining a pocket having a radius of curvature, and   providing a roller in the pocket, the roller having a radius of curvature smaller than the radius of curvature of the pocket.   
     
     
         14 . The method of  claim 12 , wherein the first control disk and the second control disk are coupled to rotate at the same angular speed. 
     
     
         15 . The method of  claim 14 , wherein the output comprises an opening and the clutch comprises a protrusion and the method comprises extending the protrusion through the opening and coupling the first and second control disks. 
     
     
         16 . The method of  claim 15 , wherein the protrusion and the opening define a gap that limits a relative rotation of the output and the first control disk. 
     
     
         17 . The method of  claim 15 , comprising providing a spring that biases the output and the input toward each other and centers the protrusion in the opening. 
     
     
         18 . A clutch comprising:
 an input,   an output, the input and the output being releasably coupled,   a first control disk between the input and the output,   a second control disk, the first control disk and the second control disk being coupled to rotate at the same angular speed, the output being moveable between the first control disk and the second control disk, and   a control that applies a torque to the second control disk to establish relative rotation between the output and the first control disk and that decouples the output and input.   
     
     
         19 . The clutch of  claim 18 , comprising:
 a groove in the output,   a groove in the first control disk, the groove in the output and the groove in the first control disk defining a pocket having a radius of curvature, and   a roller in the pocket, the roller having a radius of curvature smaller than the radius of curvature of the pocket.   
     
     
         20 . The clutch of  claim 18 , wherein the input comprises a first friction surface, wherein the output comprises a second friction surface, and wherein the input and the output are releasably coupled by contact between the first friction surface and second friction surface. 
     
     
         21 . The clutch of  claim 18 , wherein the output comprises an opening and the clutch comprises a protrusion that extends through the opening and couples the first and second control disks. 
     
     
         22 . The clutch of  claim 21 , wherein the protrusion and the opening define a gap that limits relative rotation between the output and the first control disk. 
     
     
         23 . The clutch of  claim 22 , wherein the gap limits relative rotation between the output and the first control disk to not more than 0.8 degrees. 
     
     
         24 . The clutch of  claim 22 , wherein the output has a center and wherein the gap has a width of 0.027 inches for every inch that the gap is spaced from the center of the output. 
     
     
         25 . The clutch of  claim 21  comprising multiple protrusions that extend through multiple openings in the output and that couple the first and second control disks. 
     
     
         26 . The clutch of  claim 25 , wherein the output has a center and wherein the openings are equally spaced from the center of the output. 
     
     
         27 . The clutch of  claim 21  comprising a spring between the output and the second control disk that centers the protrusion in the opening. 
     
     
         28 . The clutch of  claim 21  comprising a spring that biases the output and the input toward each other and centers the protrusion in the opening. 
     
     
         29 . A method comprising:
 providing an input and an output, the input and the output being releasably coupled,   providing a first control disk and a second control disk, the first control disk and the second control disk being coupled to rotate at the same angular speed, the first control disk being located between the input and the output, the output being moveable between the first control disk and the second control disk,   applying a torque to the second control disk to establish relative rotation between the output and the first control disk and decouple the output and input.   
     
     
         30 . The method of  claim 29 , comprising
 providing a groove in the output,   providing a groove in the first control disk, the groove in the output and the groove in the first control disk defining a pocket having a radius of curvature, and   providing a roller in the pocket, the roller having a radius of curvature smaller than the radius of curvature of the pocket.   
     
     
         31 . The method of  claim 29 , wherein the input comprises a first friction surface and the output comprises a second friction surface, the input and the output being releasably coupled by contact between the first friction surface and second friction surface. 
     
     
         32 . The method of  claim 29 , wherein the output comprises an opening and the clutch comprises a protrusion and the method comprises extending the protrusion through the opening and coupling the first and second control disks. 
     
     
         33 . The method of  claim 32 , wherein the protrusion and the opening define a gap that limits a relative rotation of the output and the first control disk. 
     
     
         34 . The method of  claim 32 , comprising providing a spring that biases the output and the input toward each other and centers the protrusion in the opening.