Limited torque coupling

Claim 2

A torque coupling comprising a hollow cylinder and an inner cylinder having a rotary coupling part extending into the hollow outer cylinder with one cylinder adapted to be an input axis and the other cylinder adapted to be an output axis, a plurality of radially extending slots opening inwardly from the inner periphery of the outer cylinder, a U-shaped spring in each slot with the ends projecting inwardly, a plate link connected to the inner projection of each U-shaped spring and linked together to a similar plate link connected to the inner projection of an aDjacent U-shaped spring to extend outwardly from a straight line position and inwardly from a straight line position between the adjacent legs of the adjacent U-shaped springs, the total length of said plate links being greater than the distance between the inner projections of adjacent legs of the U-shaped springs, the rotary coupling part having concave and convex surfaces to cooperate with the plate links to cause the outer and inner cylinders to rotate together when the plate links extend into the concave portions of the rotary coupling part, the U-shaped springs being biased to separate their legs to cause the intermediate portion of the plates between adjacent U-sahaped springs to extend in a nonstraight-line position toward the rotary coupling part to produce a driving action between the inner and outer cylinders and to extend outwardly in nondriving relation when the torque between the inner and outer cylinders exceeds a predetermined value and/or a predetermined speed, and means to urge the link plates intermediate the adjacent U-shaped springs toward the rotary coupling part to produce a driving action between the cylinders.

Claim 3

A torque coupling comprising a hollow cylinder and an inner cylinder having a rotary coupling part extending into the hollow outer cylinder with one cylinder adapted to be an input axis and the other cylinder adapted to be an output axis, a plurality of radially extending slots opening inwardly from the inner periphery of the outer cylinder, a U-shaped spring in each slot with the ends projecting inwardly, a plate link connected to the inner projection of each U-shaped spring and linked together to a similar plate link connected to the inner projection of an adjacent U-shaped spring to extend outwardly from a straight line position and inwardly from a straight line position between the adjacent legs of the adjacent U-shaped springs, the total length of said plate links being greater than the distance between the inner projections of adjacent legs of the U-shaped springs, the rotary coupling part having concave and convex surfaces to cooperate with the plate links to cause the outer and inner cylinders to rotate together when the plate links extend into the concave portions of the rotary coupling part, the U-shaped springs being biased to separate their legs to cause the intermediate portion of the plates between adjacent U-shaped springs to extend in a nonstraight-line position toward the rotary coupling part to produce a driving action between the inner and outer cylinders and to extend outwardly in nondriving relation when the torque between the inner and outer cylinders exceeds a predetermined value and/or a predetermined speed, and means to urge the plate links intermediate the adjacent U-shaped springs toward the rotary coupling part to produce a driving action between the cylinders, radial holes opening inwardly being provided on the inner periphery of the outer cylinder between the slots, a weight and a coil spring being provided in each radial hole and positioned to move the intermediate linked-together plate links inwardly at slow speeds to produce a driving action, the weights being adapted to overcome the coil spring pressure when the coupling rotates at a speed in excess of a predetermined value, thereby providing the speed control between the hollow cylinder and the inner cylinder.

Claim 4

A torque coupling comprising a hollow cylinder and an inner cylinder having a rotary coupling part extending into the hollow outer cylinder with one cylinder adapted to be an input axis and the other cylinder adapted to be an output axis, a plurality of radially extending slots opening inwardly from the inner periphery of the outer cylinder, a U-shaped spring in each slot with the ends projecting inwardly, a plate link connected to the inner projection of each U-shaped spring and linked together to a similar plate link connected to the inner projection of an adjacent U-shaped spring to extend outwardly from a straight line position and inwardly from a straight line position between the adjacent legs of the adjacent U-shaped springs, the total length of said plate links being greater than the distance between the inner projections of adjacent legs of the U-shaped springs, the rotary coupling part having concave and convex surfaces to cooperate with the plate links to cause the outer and inner cylinders to rotate together when the plate links extend into the concave portions of the rotary coupling part, the U-shaped springs being biased to separate their legs to cause the intermediate portion of the plates between adjacent U-shaped springs to extend in a nonstraight-line position toward the rotary coupling part to produce a driving action between the inner and outer cylinders and to extend outwardly in nondriving relation when the torque between the inner and outer cylinders exceeds a predetermined value and/or a predetermined speed, and means to urge the plate links intermediate the adjacent U-shaped springs toward the rotary coupling part to produce a driving action between the cylinders, radial holes opening inwardly being provided on the inner periphery of the outer cylinder between the slots, a weight and a coil spring being provided in each radial hole and positioned to move the intermediate linked-together plate links inwardly at slow speeds to produce a driving action, the weights being adapted to overcome the coil spring pressure when the coupling rotates at a speed in excess of a predetermined value, thereby providing the speed control between the hollow cylinder and the inner cylinder.

Claim 5

The invention according to claim 1 in which the concave or convex surfaces of the rotary coupling part has curvature about an axis transverse to the input and output axes whereby an angular difference between the input and output axes can be accommodated without stress.

Claim 6

The invention according to claim 1 in which the slot cavities open inwardly from one end of the hollow cylinder and such one end is closed with a lid which confines the rotary coupling part in position to operate with the plate links.

Claim 7

The invention according to claim 4 in which the U-shaped springs are held in position by bolts passing througH the slots and between the legs of the U-shaped springs and through the lid to maintain the parts in assembled relation.

Claim 8

The invention according to claim 1 in which all springs react between the hollow cylinder and the plate links to urge the plate links into driving relation with the concave and convex surfaces of the coupling part.