Abstract: An overload prevention clutch assembly features input and output members connected by a coupling member, which is resiliently deformable under the control of threaded fasteners to vary the torque which may be transmitted between the input and output members across the coupling member. The fasteners serve to mount the coupling member on the output member, whereupon the coupling and output members cooperate to mount the input member in assembled relationship therewith.

Abstract: A lever operated tool, such as a chain hoist, is provided with a free wheel mechanism allowing a lift wheel to be selectively disconnected relative to a driving gear in response to rotations of a manual control knob. The knob controls sliding movement of a driven gear mounted for rotation with the lift wheel between first and second positions in which it is engaged with and removed from engagement with the driving gear.

Abstract: A programmed action hypodermic syringe includes a syringe barrel having at least one pin protruding into the bore of the barrel. A plunger is adapted to travel through the bore and has, on its exterior surface, at least one longitudinal tracking groove defining relative motion of the pin. The tracking groove has a continuous cam side allowing unlimited travel of the pin along a complete fill or drain stroke. Opposite the continuous cam side is a discontinuous cam side defining traps for the pin should the user reverse directions before completing the fill or drain stroke. Two tracking grooves are preferably provided to define a complete allowed path along a fill tracking groove and a drain tracking groove. These two grooves converge near an end of the plunger adjacent a fluid content chamber of the syringe barrel.

Abstract: An improved push button switch has a highly desirable tactile feel. The switch includes a face plate having a front surface, a rear surface and an opening extending from the front to the rear surface, the opening having a geometric center as viewed from a position in front of the face plate. A push button is located in the opening. A pair of leaf springs are provided for coupling the push button to the face plate with at least a portion of the push button being biased against the rear surface of the face plate. A normally open electro-mechanical switch having a stationary contact and a movable contact is provided. The movable contact is biased against a portion of the rear surface of the push button at a location corresponding to the geometric center of the opening in the face plate.