GB650166A - Automatic axial pressure device applicable to friction drives - Google Patents

Abstract

650,166. Variable-speed friction gearing. SOC. DES FABRICATIONS UNICUM. Jan. 27, 1948, No. 2464. Convention date, Feb. 8, 1947. [Classes 80(i) and 80(ii)] A series of continuous cam shaped grooves 22 having medial lines arranged on a circle of radius R centered on the axis of rotation, an arcuate shape in radial section corresponding to the radius r<SP>1</SP> of balls 7<SP>1</SP>, and an arcuate shape corresponding to a larger radius r in section on the said circle characterizes an arrangement for automatically varying the axial pressure between coaxially rotating members in frictional torque transmitting devices, such as variable speed friction drives. In such a drive, Fig. 2, rollers 4 drive a disc 5 at variable speed, depending upon their radial position in relation to the disc 5 and driving discs (not shown), and the drive is conveyed through parts 17, annuli 7, 8 connected by the balls 7<SP>1</SP> sealed in the grooves 22, parts 9 and a member 16 keyed (not shown), to a driven shaft 10. All the torque conveying parts are axially slidable under the influence of a compression spring 15 which provides the basic pressure on the discs and rollers, additional pressure, related to the torque transmitted, being provided by the balls 7<SP>1</SP> partially riding up the grooves 22 on slight angular displacement of the annuli 7, 8. To damp torque fluctuations of short duration a stop pin 14 having hemispherical ends is engaged between the member 16 and a screw 13 having a coarse pitch thread, the axial position of which is controlled by a torsion spring 12 secured to an adjustable screw plug 11.