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US 4,238,978 AGranted
Torque wrench
AssigneeLowell Corporation
InventorRichard P. Leone
Life of this patent
Estimating the term…
Abstract
Torque wrench having an output shaft driven through a torque-limiting clutch including a clutch cam and a clutch ball held in driving relationship by a spring.
Claims7
A torque wrench comprising;
- (a) a housing,
- (b) an output shaft within the housing mounted for rotation about its central longitudinal axis,
- (c) a clutch cam located within the housing and operatively connected to the output shaft for rotation therewith, said clutch cam having a frusto-conical outer surface, the central longitudinal axis of the output shaft, said clutch cam also having a recessed flat surface that is parallel to said axis,
- (d) a clutch ball mounted within the housing for movement toward and away from said flat surface along a line which is substantially transverse to said longitudinal axis,
- (e) a spring for resiliently biasing the clutch ball into said recess for driving engagment with the clutch cam, whereby rotation of the housing about said longitudinal axis will cause rotation of the output shaft, said clutch ball being movable out of said recess onto said outer surface against the biasing means for disengagement of the clutch ball cam for a predetermined maximum torque of the output shaft, and
- (f) adjusting means for adjustably positioning the clutch cam along its central longitudinal axis and thereby varying the position of the clutch ball along the length of the recess for selectively varying the amount of torque required to move the ball from the recess to said conical surface.
3 more elements
Dependencies are inferred from the claim text.