Patent GB-684053-A (GB)
Title: Improvements in continuously regulable gears
IPC: F16H9/12
Filed: 1950-09-22
Abstract: 684,053. Expanding-wheel gear. PATENTVERWERTUNG W. REIMERS GES. Sept. 22, 1950 [Oct. 6, 1949], No. 23312/50. Class 80 (ii). In a continuously-regulable gear comprising friction bodies 2, 4 adjustably supported on a shaft 1, and pressed against transmission means 6 with the aid of cam surfaces 11 on a sleeve 10, supported on the shaft and bearing against an axial abutment 13, the sleeve 10 is axially slidable, and is acted on by a spring 12 which presses it against the friction bodies 2, 4 and there is provided between the sleeves 10 and the abutment 13 a braking device to movement of the sleeve towards the abutment. In the construction shown in Fig. 1, the braking device is constituted by interacting rings of the spring 12. The friction body 2 comprises a conical disc having a sleeve 3 rotatably mounted on the driving shaft 1. The sleeve of a second conical disc which forms the body 4 bears through balls 5 on an abutment of the shaft 1. The two sleeves are keyed together so that the discs 2 and 4 are rotationally fixed but the disc 2 can move axially relative to the disc 4. A transmission chain 6 is disposed between the discs 2, 4 and the output speed of revolution of the gear is varied by axial displacement of the disc 2 by means of a regulating device (not shown) applied via a ball bearing 7. The sleeve 10 is keyed to the shaft 1, but has freedom for axial movement thereto. Rolling bodies 9 are mounted between cam surfaces 8, 11 formed on respective opposed flanges on the disc 2 and the sleeve 10. The ring spring 12 acts between the sleeve 10 and an abutment 13 rigid with the shaft 1. In the position shown, in which no torque is being transmitted, the bodies 9 take up a position between the surfaces 8, 11 which permits expansion of the spring 12. In the torque-transmitting position, Fig. 2 (not shown), relative rotation between the disc 2 and sleeve 10, from their positions shown in Fig. 1, has occurred, so that the bodies 9 lie adjacent the highest points of the profiles of the cam surfaces 8, 11. The bodies 9 and cam surfaces 8, 11 thus transmit torque between the discs 2, 4 and the shaft 1, and effect loading of the spring 12. The deflection of the spring 12 is limited by positive engagement between the sleeve 10 and the abutment 13. Rebound of the spring 12 when torque transmission ceases, is damped by the inherent friction of the spring. In the construction shown in Figs. 3 and 5, the sleeve 10 is both rotatable and slidable relative to the shaft 1 and its periphery is of hexagonal form. Respective rollers 17 are disposed between each face of the sleeve 10 and the internal periphery of a cylindrical housing 16 which is rigid with the shaft 1. Compression springs 20 act between the end face of the housing 20 and the sleeve 10. A spring ring 18 is recessed into the periphery of the sleeve 10 and acts on the rollers 17. Torque is transmitted from the sleeve 10 to the housing 16 by wedging action of the rollers 17. This action also causes friction damping of relative axial movement of these parts under rebound of the springs 20 when torque transmission ceases.