Patent ID: 6131714
Filing Date: 2000-10-17
Classification: A01B,B60K

Abstract:
An auxiliary drive for a vehicle comprising:an input shaft;an output shaft;a clutch selectively engageable to couple said input shaft and said output shaft;a clutch actuating member fixed for rotation with said output shaft and movable in a first direction to engage said clutch and in a second direction to disengage said clutch; anda brake selectively engageable with said output shaft, whereby said clutch and said brake can be alternately engaged to respectively drive and brake said output shaft, wherein said brake is constituted by movement of said clutch actuating member in the second direction to engage a brake member, and said brake member includes a control apparatus selectively operable to place said brake member in an active or an inactive condition whereby said brake is rendered effective or ineffective, wherein said control apparatus includes a fluid pressure operated brake piston, said brake piston is retained against rotation with said output shaft, and said brake piston is guided on a plurality of guide bushes evenly distributed about the circumference of a circle and secured onto a housing of the auxiliary drive, an external diameter of said guide bushes having three steps, whereby: (a) said steps having the smallest diameter are adjacent to the auxiliary drive housing and form a guide for said brake piston; (b) said steps having the medium diameter form a stop limiting the travel path of said brake piston in the direction of said clutch and accommodate return springs for said brake piston, and (c) said steps having the largest diameter form a stop for said return springs.