Patent ID: 6120185
Filing Date: 2000-09-19
Classification: B65G,F16C,Y10T

Abstract:
A ball-type anti-friction mechanism comprising:(a) a housing having a chamber and a top opening to the chamber, said housing having a horizontal bottom wall which has a vertical aperture;(b) a ball cage mounted within said chamber for movement between a lower position and an upper position, said ball cage having an upper opening and defining a compression chamber between said bottom wall and said ball cage;(c) a ball mounted for universal rotation within said ball cage so that a minor portion of said ball extends above said upper opening, said ball being below said top opening when said ball cage is in said lower position and a minor portion of said ball being above said top opening when said ball cage is in said upper position; and(d) a fluid actuator for selectively positioning said ball cage in one of said upper and lower positions, said fluid actuator comprising:(1) a piston which is slidably mounted in the aperture of said bottom wall, said piston having a lower end and an upper end, said upper end being fixed to said ball cage;(2) a fluid fixture operatively connected to said compression chamber for moving said ball cage to said upper position; and(3) a return actuator for moving said ball cage to said lower position.