Overload clutch permitting torque transmission during overload

Claim 1

An overload clutch comprising a first clutch member of circular cross-section having an outer running circumference, a second clutch member of ring-shaped form having an inner running circumference in running engagement with the outer circumference of said first clutch member, a plurality of generally radially extending bores defined at angularly spaced locations in one of said first and second clutch members with the bores terminating at one end at the running circumference of the one of said first and second clutch members in which they are located, the other one of said first and second clutch members having a number of angularly spaced ball receiving recesses formed in its running circumference with the number of said recesses being less than the number of said bores and with each recess arranged to be positioned opposite a corresponding said bore, a ball carried in each of said bores, spring means located within each said bore and biasing said ball located therein radially in a direction to cause it to move into an associated said ball receiving recess to define a form-closed driving connection between said first and second clutch members, and a circumferentially extending annular safety groove formed on the running circumference of the one of said first and second clutch members containing said ball receiving recesses and having a transverse cross section smaller than the cross section of said ball receiving recesses, and said safety grooves intersecting said ball receiving recesses for providing a path for the displacement of said balls from said ball receiving recesses to said safety groove upon application of an overload torque for permitting relative rotation of said first and second clutch members, and said balls not engageable within said ball receiving recesses being positioned within said safety groove for preventing axial displacement between said first and second clutch members.