Patent GB-833768-A (GB)
Title: Improvements in or relating to resilient torque transmitting coupling arrangements
Inventor: CRUM JAMES CAMPBELL
IPC: F16D3/66
Filed: 1956-10-25
Abstract: 833,768. Resilient couplings. ROLLSROYCE Ltd. Oct. 22, 1957 [Oct. 25, 1956], No. 32628/56. Class 80 (2). A resilient coupling transmitting torque to the supercharger of an internal combustion engine comprises driving and driven members interconnected by one or more torque transmitting elements offset from the axis of rotation of the driving and driven members and extending between them in a direction skewed to the axis of rotation to transmit axial and tangential loads, the torque transmitting element or elements permitting relative rotational movement of the driving and driven members on change of the torque transmitted by the coupling against the bias of resilient means resisting this relative rotational movement, a damping device reducing the relative rotational movement on occurrence of fluctuations of torque. In one form, a driving-plate 16, Fig. 1, is fast with a gear 10 and a shaft 12, and is formed with recesses in one face co-operating with similar recesses in the adjacent face of a gear 11 rotatably mounted upon the shaft 12. The recesses contain springs 24, Fig. 2, skewed with respect to the axis of the shaft 12. As shown, the ends of the recesses are of a hemi-spherical shape and receive similarly shaped nose members 25 at the ends of the springs 24. Alternatively, the springs 24 may engage directly, with the ends of the recesses. To obtain a compact arrangement, the springs 24 are also offset from the parallel to the axis of the shaft 12, as shown in Fig. 1. The springs 24 bias the gear 11 rightwards to engage a friction damping-plate 19 carried by a flange 18 fast upon the shaft 12. When fluctuations of torque occur, the gear 11 turns relatively to the driving plate 16, so that the springs 24 flex. Change of compression of the springs 24 changes the force with which the gear 11 is pushed against the frictional damping plate 19, so that the damping effect is correspondingly increased and decreased. The lost motion which can take place between the driving-plate 16 and the driven gear 11 is limited by axial projections 26 on the gear 11 engaging with play in circumferential slots 27 around the periphery of the driving- plate 16. Lubricant is supplied to the coupling through passages 31, 28 . . . 30. In another form, a driving-shaft 40, Figs. 4, 5, has axial splines 42 engaging with lost-motion internal grooves 46 in two torque-transmitting rings 43, 44 having external splines 48 engaging with lost motion internal grooves 49 within a driven gear 41. Springs 52, skewed relatively to the axis of rotation of the shaft 40, bias the driving rings 43, 44 to turn in opposite directions and take up the lost motion between the sets of splines and grooves 42, 46: 48, 49. Simultaneously, the axial component of the bias of the spring 52 tends to separate the two driving-rings 43, 44 and force them into engagement with flange rings 54 fast with the driven gear 41, to obtain friction damping. On relative rotation occurring between the driving-shaft 40 and the driven gear 41 with changes of torque, the springs 52 are compressed, the driving rings 43, 44 turn relatively to each other up to a limit determined by the lost motion in the spline and groove connections 42, 46; 48, 49, and relative rotation between the parts is damped by the driving-rings spring-biased to frictionally engage the flanged rings 54. In yet another form, a driving-shaft 60, Fig. 7, and a flange 60a carry rotatably a driven gear 61. A driving ring 65 has splines 66 engaging similar splines within the gear 61, and is in driving connection with the flange 60a by means of pivoted struts 68, skewed relatively to the axis of the shaft 60, engaging recesses in the flange 60a and the driving-ring. A spring 67 biases the driving- ring 65 rightwards, and simultaneously biases the driven gear 61 leftwards to engage frictionally with a ring 64 fast upon the shaft 60. When fluctuations of torque occur, the driven gear 61 turns relatively to the shaft 60, so that the skewed struts 68 pivot and move the driving- ring 65 leftwards, thus increasing the bias of the spring 67, and the driven gear 61 frictionally engaging the ring 64 dampens the relative rotation between the parts.