US 4,770,281 A · Overload apparatus

Abstract

An overload apparatus is shown as an overload single position clutch having a drive ring which is reciprocated by springs and by a cylinder slideable on a piston by fluid pressure. The drive ring includes a multiplicity of ball receiving cavities. A sheave mount is further provided including an integral interface disc having a multiplicity of ball carrying cavities. Balls are captured within the ball carrying cavities by a ball cage secured to the mount. The ball cavities have diameters less than the balls and a shape and size such that the balls do not touch the closed ends or sidewalls of the cavities but rather the open ends form seats for the balls. The ball carrying cavities have diameters greater than the diameters of the ball receiving cavities to predispose the balls to cam out of the ball receiving cavities in the event of reaching a torque overload level. In another embodiment the balls are captured in the ball carrying cavities by constant diameter apertures formed in a carrier ring and a retaining plate, with the aperture diameters of the carrier ring being generally equal to that of the balls and with the aperture diameters of the retaining ring being less than that of the balls.

Claims19

Dependent claims

Overload apparatus comprising, in combination:

a first disc having an inner face;
a second disc having an inner face, with the inner face of the second disc being substantially adjacent and parallel to the inner face of the first disc;
at least one ball having a diameter;
a ball carrying cavity for each ball formed in the first disc extending axially of the inner face of the first disc, with the ball carrying cavity having a diameter, with the diameter of the ball being greater than the diameter of the ball carrying cavity;
means for capturing the ball within the ball carrying cavity;
and a ball receiving cavity for each ball formed in the second disc extending axially of the inner face of the second disc, with the ball receiving cavity having a diameter less than the diameter of the ball and less than the diameter of the ball carrying cavity whereby the ball cams out of the ball receiving cavity rather than from the ball carrying cavity in the event of reaching a torque overload level.

3 more elements

Overload apparatus comprising, in combination:

a first disc having an inner face;
a second disc having an inner face, with the inner face of the second disc being substantially adjacent and parallel to the inner face of the first disc;
at least one ball having a diameter;
a ball carrying cavity for each ball formed in the first disc extending axially of the inner face of the first disc, with the ball carrying cavity having a diameter, with the diameter of the ball being greater than the diameter of the ball carrying cavity;
a ball receiving cavity for each ball formed in the second disc extending axially of the inner face of the second disc;
a carrier ring;
a retaining plate;
and means for securing the carrier ring and the retaining plate to the first disc with the carrier ring sandwiched between the retaining plate and the first disc, with the carrier ring including an aperture for each of the balls having a constant diameter for receipt of the diameter of the ball, with the retaining plate including an aperture for each of the balls having a constant diameter less than the diameter of the ball, with the ball captured within the ball carrying cavity and the apertures of the carrier ring and retaining plate extending through and beyond the aperture of the retaining plate.

5 more elements

Dependencies are inferred from the claim text.

Overload apparatus

Life of this patent

Overload apparatus

Life of this patent

Abstract

Claims19