Abstract: A clutch unit especially adapted for accurately controlling the transmission of high rotary forces with minimum residual drag. A servo control valve supplied with hydraulic fluid by a pump controls a first stage fluid amplifier supplied by a separate pump, this amplifier in turn controlling a second stage amplifier supplied by a third pump. The second stage amplifier supplies main and auxiliary inlet ports of the clutch unit. The oil shear type clutch has a plurality of interleaved plates and discs. Separate piston and cylinder means are provided for actuating the plates for each clutch disc by means of the main fluid supply, the pressure of which is varied in accordance with input signals to the servo control valve. The auxiliary supply to the clutch acts both to retract the piston and cylinder means, thus separating the plates and discs with a minimum of residual drag, and as a cooling medium.

Abstract: A clutch-brake unit having aligned input and output shafts, clutch plates carried by the input shaft, brake plates fixed to the housing, two series of friction discs secured to the output shaft and engageable alternately with the clutch or brake plates by means of a piston which actuates clutch and brake actuating members, and oil cooling means for the assembly including a pump, the output of which is proportional to the speed differential between the shafts. The pump is illustrated as being a Gerotor type of pump mounted between the shafts with its external element connected to the input shaft and its internal element to the output shaft.

Abstract: A clutch unit for selectively drivingly connecting driving and driven shafts, the unit comprising, a first plurality of discs connected with one of the shafts and a second plurality of discs connected with the other of the shafts, the first and second plurality of discs being interleaved and being movable toward and away from one another to drivingly connect the driving and driven shafts, selective of the discs being fabricated of circumferentially arranged disc segments whereby the diameter of the discs (and hence the capacity of the clutch unit), may be increased significantly as compared to existing and prior known clutch units of the same general type.

Abstract: A clutch assembly is located in the bore of a flywheel for drivingly connecting a coaxially located shaft. The assembly is comprised of a first series of discs mounted for rotation with the shaft, and a second series of interleaved plates supported for rotation with the flywheel. The flywheel is connected to the drive shaft in response to displacement of an actuating means which compressively engages the discs and plates. A separate brake assembly is provided which can be located at either axial end of the shaft, and in one form of the invention, hydraulic fluid is circulated through each of the clutch and brake assemblies from a common source.