Power transmission having power take-off shaft and fluid control means therefor

A tractor power transmission having a non-rotatable housing, a change speed gear mechanism mounted in said housing for propelling the tractor at different speeds, a power input shaft for said mechanism, said mechanism including a duplex clutch assembly mounted on said input shaft, said assembly including a pair of selectively engageable clutches each having a gear for transmitting power through said mechanism;

• a power take-off shaft journalled adjacent said input shaft and in coaxial alignment therewith, said power take-off shaft having means for connection to an implement or the like to be driven by said power take-off shaft;
• a duplex clutch for (1) selectively detachably connecting said shafts together or (2) disconnecting said shafts and locking said power take-off shaft to the transmission housing, said duplex clutch including a hydraulically actuated friction plate clutch having a second output part splined to said power take-off shaft for rotation therewith, and interleaved clutch plates between said parts, a hydraulically actuated piston slideably mounted on said second part and defining therewith an expansible fluid chamber for clamping up said plates and thereby forming a driving connection between said shafts, said duplex clutch also having a brake including interleaved friction plates between said housing and said second part of said clutch, said piston and said second part defining a second chamber for actuating said brake, spring means acting between said second part and said piston, and lubricating fluid passage means in said second part and communicating with said second chamber for conducting lubricating fluid to said second chamber to assist said spring means in biasing said brake to an engaged position by clamping up said plates of said brake for locking said power take-off shaft to said housing when the plates of said clutch are unclamped and said clutch is disconnected.

In a tractor power transmission having a change speed gear mechanism mounted in a non-rotatable housing and for propelling the tractor over the ground at different speeds, a power input shaft for said mechanism, said mechanism including a duplex clutch assembly mounted on said input shaft, said assembly including a pair of selectively engagable clutches each having a gear for transmitting power through said mechanism;

• said power input shaft having a rear end, a power take-off shaft having one end journalled adjacent said rear end and in coaxial alignment therewith, another end of said power take-off shaft having means for connection to an implement or the like to be driven by said power take-off shaft;
• a duplex clutch for (1) selectively detachably connecting said shafts together or (2) disconnecting said shafts and locking said power take-off shaft to the transmission housing, said duplex clutch including a hydraulically actuated friction plate clutch having a first input part connected to said power shaft and having a second output part splined to said power take-off shaft for rotation therewith, said interleaved clutch plates between said parts, a hydraulically actuated piston slideably mounted on said second part for clamping up said plates and thereby forming a driving connection between said shafts, said duplex clutch also having a brake including interleaved friction plates between said housing and said second part of said clutch, said piston and said second part defining a second chamber for actuating said brake, spring means acting between said second part and said piston, and lubricating fluid passage means in said second part and communicating with said second chamber for conducting lubricating fluid to said second chamber, to assist said spring means in biasing said brake to an engaged position by clamping up said plates of said brake for locking said power take-off shaft to said housing when the plates of said clutch are unclamped and said clutch is disconnected, and operator control valve means for operating said piston to cause said clamp-up of the plates of said clutch.