Patent ID: 7416216
Filing Date: 2008-08-26
Classification: B62D,F16C,F16D,Y10T

Abstract:
1. A telescopic shaft for vehicle steering which is installed in a steering shaft of a vehicle and in which a male shaft and a female shaft are fitted to each other for relative telescopic movement and for torque transmission therebetween, characterized in that: rolling elements, which rotate in response to relative telescopic movement between the male and female shafts, are disposed between at least one first pair of axially extending grooves, the first pair of grooves being formed respectively on an outer peripheral surface of said male shaft and on an inner peripheral surface of said female shaft; a pair of raceway surface elements is interposed between said rolling elements and said male shaft or said female shaft in the corresponding first pair of grooves, said pair of raceway surface elements being disposed side by side in a circumferential direction of said telescopic shaft and each being in contact with said rolling elements and an elastic member for preloading said rolling elements against one of said male and female shafts through said pair of raceway surface elements; and at least one columnar member, which slides in response to relative telescopic movement between the male and female shafts, is received, with a small gap, in grooves of at least one second pair of axially extending grooves formed respectively on the outer peripheral surface of said male shaft and on the inner peripheral surface of said female shaft.