Abstract: A clutch arrangement for a multi-spindle machine includes a starting clutch 12 and a machine brake clutch 14 positioned on a starting clutch drive shaft 16. A high speed clutch 18 and a snubbing clutch 22 are positioned on a long worm drive shaft 20. All clutches are pneumatically operated by solenoid valves 40, 42, 44 and 46 and electrically actuated by electrical circuit 60. When the multi-spindle machine shifts from a high speed to a low speed, the present invention activates the machine brake clutch 14 and snubbing clutch 22 for a predetermined time period to cause the drive train gears to slow down allowing synchronous meshing with the low speed drive train of the multi-spindle machine to enable a reduction in machine cycle time.

Abstract: A power take-off unit includes a hydraulically actuated brake assembly which is automatically engaged when a hydraulically actuated clutch assembly is disengaged, and further which is automatically disengaged when the clutch assembly is engaged. The power take-off unit includes a housing which contains an input gear and an output shaft. The input gear is adapted to be connected to an engine or transmission of a vehicle or other source of rotational power so as to be rotatably driven in a conventional manner. The output shaft is adapted to be connected to rotatably driven accessory, such as a hydraulic pump. The power take-off unit includes a clutch assembly for selectively providing a driving connection between the input gear and the output shaft and a brake assembly for selectively exerting a braking force to retard rotation of the output shaft.

Abstract: A power-take-off of a utility vehicle such as an agricultural tractor has a clutch (3) and a brake (18) to retain the output shaft against rotation when the clutch is disengaged. The invention provides a means of automatically disengaging the brake to permit rotation of the output shaft for the purpose of coupling an implement thereto. In one embodiment, the clutch and brake are engaged by fluid under pressure, and are disengaged by stopping the vehicle engine and thus allowing engine generated fluid pressure to decay.

Abstract: A mechanical press having a wet or oil shear clutch/brake drive unit is provided including elimination of undamped clearances. Lubrication oil utilized in the press flywheel bearing is ported and communicated into the clutch brake unit for use therein, eliminating the use of two separate lubrication or oil transport systems. A hydrostatic oil bearing on the brake/clutch actuator member (actuation plate) eliminates the use or need of an anti-friction bearing between the actuator member and the brake and clutch members.

Abstract: A hydraulic system for a power-take-off in a utility vehicle is described, having a pump (8) supplying hydraulic fluid to the clutch (1), the brake (2) and a lubricating circuit, a control valve for engaging and releasing the clutch and a device containing a pressure-limiting valve (12) which makes a high system pressure available when the clutch is engaged and a lower system pressure when the clutch is released.In order to keep loss of power in the pump as low as possible and reduce the number of components required in a hydraulic system of this type, the system pressures are controlled by the pressure applied to the engaged clutch. Consequently, the system pressures can be adjusted regardless of the design of control valve used. This means that less expensive 3/2-way valves or 3/2-control valves can be used. This also has an advantage in that different system pressures can be produced using a single pressure-limiting valve.

Abstract: A pressure control valve having an electric first stage pilot with a single pilot outlet port and providing a variable pressurized hydraulic fluid to the pilot outlet port and at a pressure that is proportional to an electric input signal variable between first and second values. A second stage hydraulic valve is provided which has a valve body with a spool reciprocally movable in a bore. A first end of the bore is coupled to the aforesaid pilot outlet port. A spring abutment is provided in the bore at a second end remote from the first end, and a spring is oriented between and abuts the spring abutment and one end of the spool remote from the pilot outlet port for urging the spool to oppose the pressurized hydraulic fluid at the pilot outlet port.

Abstract: An arrangement of foot operated elements for a motor vehicle includes a first element with a power booster for operating a brake and a second element with a second power booster for operating a clutch of the motor vehicle. The second power booster for actuating the clutch release is arranged adjacent the power booster for actuating the brake device. The power booster for the clutch has a linear guide which guides the second element, which is an actuating push rod by which the second power booster for the clutch can be operated directly. The second power booster for the clutch further has a servo device which further reduces the actuating forces and/or the operating paths for actuating the clutch.

Abstract: The present invention provides a hydraulic motion control or pilot valve and lever assembly for controlling the transmission and steering of a work vehicle such as a crawler tractor, articulated wheel loader or like construction vehicle. The motion control valve and lever assembly is a compact assembly that employs a single lever mounted directly to a valve in order to control the forward and reverse motion of the vehicle, the steering of the vehicle in a left, right or straight direction, and the speed or gear selection of the vehicle. The valve assembly is provided with eight hydraulic signal ports, at least one reservoir port, and at least one pressure supply port. The assembly further has four control spools positioned in respective control spool chambers spaced approximately ninety degrees apart and a fifth control spool positioned in a fifth, central spool chamber.

Abstract: A power take off (PTO) clutch control system for an agricultural tractor is disclosed herein. The PTO clutch is a hydraulic clutch which is operated by a proportional valve capable of pressurizing the clutch with hydraulic fluid at a pressure related to the pulse width of a pulse width modulated (PWM) control signal applied to the valve. The PWM signal is produced by a controller which monitors the input shaft speed and the output shaft speed. A first control signal is applied to the valve when both the input and output shaft speeds are greater than zero. A second control signal is applied to the valve when the input shaft speed has decreased by a predetermined amount and the output shaft speed is substantially zero.

Abstract: A hydraulic emergency circuit for a hydraulically-operated friction clutch disposed as a part as an electro-hydraulic clutch control between an internal combustion engine and a transmission has a hydraulic pump provided for supplying at least one working line and connected with a power take-off shaft of the internal combustion engine, a throttle valve disposed in the working line, two control lines branching off upstream and downstream of the throttle valve, and a switch valve connected with the control lines and provided for controlling and operating a supply of pressure for the friction clutch, the control line upstream of the throttle valve being connected to a first control input of the switch valve, the control line disposed downstream of the throttle valve being in hydraulic connection with a second control input of the switch valve which is located approximately opposite to the first control input, and a restoring string disposed on a control piston side adjoining the second control input.

Abstract: Disclosed is a modulating hydraulic circuit for controlling a clutch such as the clutch on a power takeoff (PTO) shaft. The circuit includes a throttling valve having (a) an inlet port for receiving hydraulic fluid from a source, and (b) a discharge port connected to the clutch. The discharge port is also connected to an accumulator which is at an accumulator pressure. The discharge port and the clutch are at a pressure generally proportional to the accumulator pressure. As accumlator pressure rises at a controlled rate, the clutch is progressively engaged. Optionally, the circuit includes a brake control valve for "softly" disengaging a PTO shaft brake as the accumulator pressure rises. A method for controlling the clutch includes flowing hydraulic fluid through hydraulic lines to a throttling valve connected to an accumulator and to the clutch, increasing pressure in the lines and progressively engaging the clutch.

Abstract: A press includes a drive system which includes a brake and a clutch operated by fluid pressure. The brake and clutch control the movement of a crankshaft in relation to a flywheel. A unique control system supplies the pressurized fluid for operation of the brake and clutch. The unique control system includes a pressure relief valve for defining a maximum fluid pressure and a plurality of valve modules which each define a specific fluid pressure. Each valve module is selectively movable between a relief condition and a blocked condition. Thus, by selectively operating the valve modules, it is possible to select the fluid pressure being supplied to the brake and clutch.

Abstract: A drive unit for driving a press is disclosed. The drive unit uses a hydraulically actuated oil shear brake unit located on one side of a flywheel and a hydraulically actuated oil shear clutch unit located on the opposite side if the flywheel. The brake is normally biased into its applied condition and the clutch is normally biased into its disengaged position. The engagement of the clutch and the release of the brake occur from the same hydraulic pressure source. The amount of overlap between the two units is accurately controlled by varying the biasing loads of the assemblies and accurately setting the stroke of the actuation member for each assembly.

Abstract: A control system for a press having a clutch and a brake includes a clutch control valve and a brake control valve. The clutch control valve operates the clutch by supplying pressurized air to the clutch. The brake control valve operates the brake by supplying pressurized hydraulic fluid to the brake. The brake control valve is activated by pressurized fluid from the clutch control valve in order to insure simultaneous release of the brake with engagement of the clutch as well as simultaneous application of the brake with disengagement of the clutch.

Abstract: The invention provides an overspeed protection system for a vehicle such as a mine skip travelling along a vertical set of rails 60. In use an idler wheel 62 in contact with a rail 60 rotates a shaft 12 forming part of a clutch 10 at speeds which are directly proportional to the linear travelling speed of the vehicle. When the rotational speed of the shaft 12 exceeds a predetermined limit the clutch 10 frictionally transfers torque from the shaft 12 to a shaft 14, which in turn drives an hydraulic pump 64. The pump 64 pressurises hydraulic fluid in a supply line 67 until it opens a valve 68, which admits a pressurised fluid from a reservoir 74 into a braking means 80, which performs a clamping action on an associated rail 60 to restrain the motion of the vehicle.

Abstract: A power take off (PTO) clutch control system is disclosed herein. The PTO clutch is a hydraulic clutch which is operated by a proportional valve capable of pressurizing the clutch with hydraulic fluid at a pressure related to the pulse width of a pulse width modulated (PWM) signal applied to the valve. The PWM signal is produced by a controller which monitors the input and output shaft speeds to determine the pulse width of the PWM signal. The clutch control also includes a brake which inhibits rotation of the clutch output shaft when the clutch is disengaged. The brake is operated by an on/off valve which is also controlled by the controller.

Abstract: A power take off (PTO) clutch control system is disclosed herein. The PTO clutch is a hydraulic clutch which is operated by a proportional valve capable of pressurizing the clutch with hydraulic fluid at a pressure related to the pulse width of a pulse width modulated (PWM) signal applied to the valve. The PWM signal is produced by a controller which monitors the output shaft speed and movement to determine the time at which the shaft begins movement. Prior to shaft movement, the PWM signals control the proportional valve to engage the clutch slowly and smoothly to avoid producing unacceptably high torques in the PTO shaft connected to the clutch during clutch engagement.

Abstract: A base unit for driving a press is disclosed. The unit uses two hydraulic actuated oil shear brake/clutch units which are in coaxial nested relationship. The basic unit provides a core assembly which can easily be modified or adapted to be mated with any type of press drive. The unit provides the normal start-stop function of a press drive using the two brake/clutch units as well as a flywheel braking function utilizing the same two brake/clutch units.

Abstract: A steering control system provides a pilot pressure capable of ensuring excellent responsiveness and light operation force and constant shifting strokes of the control lever even in case of wear of the brake and the clutch. The control lever (1) for use in rightward and leftward steering is directly coupled to the pilot pressure control valve (2) and the pilot pressure control valve (2) is coupled to the clutch piston (4) for ON/OFF operation of the clutch (3) and to the brake cylinder (6) for ON/OFF operation of the brake (5) with piping (10,17). When the control lever (1) is shifted to the right or the left, the pilot pressure control valve (2) at the operation side is actuated to set the associated clutch to OFF and then the associated brake to ON.

Abstract: A pair of selectively operable torque transmitting devices, such as a clutch and brake, are provided to control the torque and speed ratio in a planetary gear set. One device, a clutch, is spring engaged, to provide direct drive in the planetary set, and fluid released by a selectively operable piston assembly. The other device, a brake, is pressure engaged by a selectively operable piston assembly to establish a drive ratio in the planetary set. A torque responsive mechanism is incorporated in the piston assembly to control the overlap between the clutch/brake exchange during a ratio interchange.

Abstract: A dual piston hydraulic cylinder for actuating a clutch and an upshift brake in a heavy-duty vehicle is provided which achieves consistent, selectable, sequential, and controllable operation utilizing a single control pedal. A preloaded spring located between two pistons sequences the pressure accumulation and fluid flow to actuate the clutch and the upshift brake in such a manner so as to preclude brake actuation unless the clutch is disengaged. A fluid reservoir in selective fluid communication with the hydraulic cylinder automatically adjusts the separate fluid links between the clutch and the upshift brake to compensate for changes in their corresponding engaged positions due to wear. The apparatus disclosed accommodates the use of disparately designed clutches and upshift brakes.

Abstract: A friction clutch mounted in a transmission case (25) or the like and connected between a drive shaft (14) for receiving engine power and a driven shaft (15) for receiving power from the drive shaft and transmitting the power to a power takeoff shaft (11). The friction clutch includes a first sleeve (17) connected to the drive shaft, a second sleeve (16) connected to the driven shaft, friction disks (18, 19) disposed between the first sleeve and the second sleeve, the friction disks being switchable between a clutch engaging state to enable power transmission between the first sleeve and the second sleeve, and a clutch disengaging state to disable the power transmission, and a clutch piston (20) movable between a first position to place the friction disks in the clutch engaging state, and a second position to place the friction disks in the clutch disengaging state.

Abstract: A clutch mechanism having a drive shaft operatively connected to a drive section of a working vehicle, and a driven shaft connected to a working implement such as a mower unit. The clutch mechanism includes a clutch mounted on the drive shaft to be operable between an ON state to transmit drive from the drive shaft to the driven shaft, and an OFF state to break drive transmission; a transmission shaft connected to the clutch; and a shift device connected to the clutch to be shiftable between a first position corresponding to the ON state of the clutch and a second position corresponding to the OFF state of the clutch. The shift device has a clutch control device shiftable to control the clutch, and a first helical gear axially movably mounted on the transmission shaft. The clutch mechanism further includes a second helical gear rotatable with the driven shaft and meshed with the first helical gear, and a brake for applying a braking force to the shift device when the shift device is in the second position.

Abstract: A device for controlling hydraulic steering clutches and brakes in a crawler vehicle such as a bulldozer has a simple structure so as to be manipulated by a monolever. The device comprises a single steering lever (5), four proportional pressure control valves (1), (2), (3), (4), left and right steering clutch pistons (7), (7a) and left and right brake cylinders (8), (8a). The four valves are composed of two sets of valves, one set of two valves for steering clutches, in which the timing of the rise of hydraulic pressure is earlier, and one set of two valves for brakes, in which the timing of the rise of hydraulic pressure is later than the former.

Abstract: An improved coupling assembly includes a combined clutch and brake assembly. Springs are provided to urge the brake assembly to an engaged condition. A first pressure chamber holds fluid pressure to assist the springs in urging the brake assembly toward the engaged condition. A second chamber holds fluid pressure to urge the clutch assembly toward the engaged condition and to urge the brake assembly away from the engaged condition. Fluid is supplied at a relatively low pressure through the first chamber to provide for a controlled actuation of the brake assembly to the engaged condition under the combined influence of the springs and the pressure in the first chamber and to provide for the transmission of a controlled amount of braking torque when the brake assembly is engaged. Fluid is supplied to the second chamber at a higher pressure to overcome the influence of the springs and operate the clutch assembly to the engaged condition.

Abstract: Two solenoid-actuated shuttle valves selectively direct hydraulic fluid from a line pressure source to a clutch and brake servo or direct fluid from the clutch and servo to a low pressure drain, in accordance with the combined states of the solenoids. The system includes several orifices, which in combination control the rate of flow between the pressure source and the friction elements. The orifices control also the flow rate in the system between the friction elements and drain ports. Accumulators are located in the system between the shuttle valves and the friction elements. An arrangement of check valves and orifices located between the shuttle valves and the accumulators establish the rate of flow between each of the accumulators and the associated friction element.

Abstract: A supporting structure for control elements of an automatic transmission including a multiple-disc clutch having a piston operated by hydraulic pressure from a control valve unit and a cylinder slidably supporting the piston, and a one-way clutch having outer and inner races and a series of sprags placed between both of the races so as to mechanically jam depending on the rotational direction of the outer race, comprises a support member comprised of the cylinder and the inner race which are integrally formed with each other, and a transmission case for fixing the support member on the inner surface thereof from the inside of the transmission case by means of bolts.

Abstract: The invention relates to an electrohydraulic control for an automatic transmission of a motor vehicle. In order to be able to utilize, in the coasting operation of the motor vehicle in the driving position D of the automatic transmission, also the first gear, a one-way clutch, which transmits only driving torques but is required for the shifting operation, when the first gear is engaged, is bridged by a brake so that the transmission can transmit not only driving but also coasting torques and can therefore transmit the engine braking torque.

Abstract: A basic unit for driving a press is disclosed. The unit uses two hydraulic actuated oil shear brake/clutch units which are in coaxial nested relationship. The basic unit provides a core assembly which can easily be modified or adapted to be mated with any type of press drive. Once the unit has been mated to a press a continuous supply of filtered and cooled oil is provided. This supply of oil provides little or no wear on clutch plates as well as low heat generation.

Abstract: A coupling assembly includes a clutch assembly and a brake assembly. The brake assembly includes an annular piston which is formed as one piece with a base member. An annular cylinder chamber is formed as one piece with a second member and telescopically receives the annular piston. Force transmitting surfaces on the two members engage opposite sides of a friction disk. The annular piston and cylinder extend around the outside of the friction disk to at least partially block a flow of contaminants in a radially inward direction toward the friction disk. Passages are formed in a lower portion of the annular piston to accommodate a flow of cooling fluid and to enable any contaminants which enter the brake assembly to flow out of the brake assembly. The brake assembly is advantageously urged to an engaged condition by spring assemblies which include posts and spring elements which extend into a space between the clutch assembly and a flange portion of a flywheel.

Abstract: An improved braking mechanism (100) is provided for use in conjunction with a change gear transmission (50) that is selectively engagable with a vehicle engine (4) by a clutch (3). Mechanism (100) has a piston (22) slidably received in a primary fluid chamber (34) that is operative to cause mechanism (100) to act as an inertia brake upon establishment of a first set of predetermined operating conditions. Piston (22) is also slidably received in a secondary fluid chamber (36) that is operative to cause mechanism (100) to act as a hill holding brake upon establishment of a second predetermined set of operating conditions.

Abstract: The stem of an inching valve for a power-shift transmission, particularly for lift trucks, is controlled by a hydraulically-operated piston whose axis is distinct from and parallel to the axis of the stem and which is connected to the stem by means of a mechanical transmission. The risk of contamination of the fluid used for operating the piston (which is the fluid of the vehicle's braking circuit) by the oil used in the power-shift transmission is thus avoided.

Abstract: A hydraulic modulation valve for use in conjuction with a tractor power-takeoff shaft to prevent an instantaneous loading of the hydraulic clutch controlling the operation of the power-takeoff shaft is disclosed wherein the supply line leading from the valve spool to the hydraulic clutch is in flow communication with a modulation chamber. A yieldable spring-loaded piston is moved within the modulation chamber from an initial position to an operating position to allow the hydraulic pressure to increase from zero pressure to a working pressure for the hydraulic clutch. A bypass line bleeds hydraulic fluid from the inlet end of the modulation chamber to slow the rate at which hydraulic pressure is increased within the modulation chamber.

Abstract: A fluid control circuit for controlling the disengagement of first and second drive mechanisms and the engagement of first and second brake mechanisms for a track-type vehicle has a fluid pump and first and second foot operated fluid control valves in fluid communication with the pump. Shifting of either control valve individually disengages the associated drive mechanism and engages the associated brake mechanism. Shifting of both control valves concurrently, engages both first and second brake mechanisms while the first and second drive mechanisms remain engaged. Conventional track-type vehicles use two pedals to sequentially control the disengagement of first and second drive mechanisms and the engagement of associated brake mechanisms. A third pedal controls engagement of both brake mechanisms without disengaging the drive mechanisms. The three pedals complicate the control system and create a crowded operator's station.

Abstract: Clutch and brake apparatus that is operable by a compressible fluid, particularly pneumatically, includes input and output shafts mounted in a common housing that has a clutch chamber. A clutch plate and a clutch flange are mounted in the clutch chamber with the flange being fixed to the input shaft and the clutch plate dividing the clutch chamber into two operating chambers that are adapted to be at different fluid pressures. A friction lining is fixed to at least one of the clutch plate and clutch flange for engaging the other. A clutch plate is mounted to be axially displacable relative to the output shaft in every load condition while at least one torque plate is fixed to rotate with the output shaft and a peripheral portion of the clutch plate. The torque plate is subjected to the same fluid pressure on both sides. The apparatus is able to operated with a large pressure differences across the clutch plate without danger of damaging the clutch plate.

Abstract: A power take-off control lever arrangement in which a single control lever 32 controls an engine speed power take-off clutch C2, a ground speed power take-off clutch C2 and a power take-off brake B. The control lever 32 is movable between positions C1' and B' in which switches 28 and 29 are operated to initiate engagement of the engine speed clutch C1 and brake B respectively which are both hydraulically operated. Lever 32 is also movable against the action of spring loading 49, to a position G in which it engages a fork 43 of a mechanical actuating system 43, 41, 31 for the ground speed clutch C2. Movement of lever 32 from position G to position C2' moves the mechanical actuating system to engage clutch C2. Lever 32 is only movable from position C2' to positions C1' and B' via position G to ensure disengagement of the ground speed clutch C2 before initiation of the engagement of the engine speed clutch c1 or the brake B.

Abstract: An inertial brake unit for an air clutch includes a concentric inertial brake chamber in a rotary joint for the air clutch, a disc brake, a piston and a pressure chamber. The brake unit also includes a pneumatic pressure control mechanism so that the piston can brake the disc when pressurized air is supplied to said pressure chamber at the time of disengaging the clutch.

Abstract: A clutch and brake assembly for alternately coupling a machine input shaft to a clutch disc or a brake disc for applying a driving torque or a braking torque to the input shaft. An axially movable cylinder is connected to a brake plate and a clutch plate. An annular piston is carried by a hub fixed to the input shaft and is connected to a rotor spaced at an axially fixed distance from the piston. The brake disc is positioned between the brake plate and the rotor while the clutch disc is positioned between the clutch plate and the rotor. A spring force normally urges the brake disc into engagement with the rotor. A pressure chamber is formed between the piston and cylinder and a passage is provided for admitting pressurized fluid to the chamber, thereby overcoming the spring force to urge the clutch disc into engagement with the rotor.

Abstract: A two speed axle assembly for automotive vehicles, providing positive shift engagement in shifting between direct and overdrive modes. Input and output shafts carry respective input and output sun gears meshed with compound planetary gears within a rotatable planet carrier. A pair of clutch packs selectively lock the planet carrier either to the input sun gear for rotation therewith as a unit for one mode of operation, or to the axle carrier case so that rotation of the planet carrier is prevented and the planet gears rotate about their axes to provide the other mode of operation. Compression springs are utilized to normally load the one clutch pack and lock the planet carrier to the input sun gear for the direct drive mode. A hydraulic bladder assembly is provided for shifting from the direct to the overdrive mode. Upon hydraulic inflation of the bladder, a bladder piston simultaneously unloads the one clutch pack and loads the other, locking the planet carrier to the axle carrier case.

Abstract: An inching drive unit for a brake unit, clutch/brake unit, or the like is disclosed for which an inching motor is able to drive an accessory attached to the main motor through the main motor shaft. The inching drive unit includes a clutch unit for selectively engaging the main motor shaft with a gear mechanism attached to the inching motor drive shaft. A brake is further provided which selectively restricts the rotation of the inching motor drive shaft, and brakes the main motor shaft when the clutch is engaged.

Abstract: A clutch and brake apparatus for being mounted in a housing comprises first clutch having an annular shape and second clutch functioning as a brake adjacent the first clutch, the second clutch having an annular shape and being concentrically disposed with the first clutch. A pressure plate is mounted for non-rotating movement toward and away from the first and second clutches for selectively engaging at least one of the first and second clutches and for holding the pressure plate in a rotationally stationary position with respect to the housing and second clutch. Structure is provided for urging the pressure plate toward both the first and second clutches and is operable to engage the first clutch. Roller bearings are interposed between the first clutch and the pressure plate to permit relative movement between the pressure plate and the first clutch.

Abstract: A steering control system for applying brakes to engine powered vehicles having power-shifting hydraulic fluid transmissions. An interface value is provided to sense a pressure signal of hydraulic fluid that is proportional to ground speed movement of a vehicle. A control value transforms the signal generated by fluid pressure into associative structure for applying vehicle brakes in a manner proportional to vehicle ground speed, either in a forward or reverse direction. Dual pressure regulating valves are provided wherein one value is set at a higher pressure than the other values for eliminating a need for two sources of pressure and/or a pressure accumulator.

Abstract: An inching drive unit for a brake unit, clutch/brake unit, or the like, the unit having a housing and a main rotatable member operably associated with a first portion of the housing, the inching drive unit comprising an inching motor having a drive shaft, a second portion of the housing secured to the inching motor into which the inching motor drive shaft extends, a first gear mechanism disposed at least in part within the inching drive portion of the housing and operably associated with the inching motor drive shaft, a second rotatable member mechanism operably associated with the main rotatable member, and a mechanism for selectively engaging the first gear mechanism with the second rotatable member mechanism wherein engagement of the first gear mechanism with the second rotatable member mechanism permits the inching motor to drive the input shaft of the clutch/brake unit.

Abstract: A method of making a tensioner for a power transmission belt that is adapted to be operated in an endless path is provided and comprises the steps of providing a support unit for being fixed relative to the belt, providing a belt engaging unit to be carried by the support unit and be movable relative thereto, operatively associating a mechanical spring unit with the support unit and the belt engaging unit for urging the belt engaging unit relative to the support unit and against the belt with a force to tension the belt, operatively associating a fluid dampening unit with the support unit and the belt engaging unit to dampen the movement of the belt engaging unit relative to the support unit in at least one direction thereof, forming the mechanical spring unit to comprise a pair of springs disposed in substantially parallel spaced relation, disposing at least a part of the fluid dampening unit between the springs and in substantially parallel relation therewith, and forming the fluid dampening unit to compris

Abstract: A transmission shaft (62) mounting thereon fluid-operated clutch means (68) which discontinues selectively the input of power to such shaft is enclosed at one end portion thereof by a hollow cylinder (86) projected inwardly from an inner wall surface of transmission case (28) for power transmission. An annular groove (89) formed to said one end portion of shaft (62) at the outer peripheral surface thereof and communicated to the clutch means (68) via fluid path (85) in the shaft (62) is sealed by the hollow cylinder (86) so as to form an annular fluid chamber (90) which constitutes a rotary joint portion of fluid conduit line for the clutch means (68). Braking mechanism of a brake (69) associated with the clutch means (69) for braking the shaft (62) in the non-operated state of clutch is arranged within the hollow cylinder (86) by employing such cylinder as brake case.

Abstract: A fluid operated clutch and brake assembly is adapted to be connected to a motor driven flywheel and a rotatable drive shaft for a press or the like. A fluid operated piston mounted on the flywheel simultaneously engages the clutch and disengages the brake. The brake is spring biased to automatically stop rotation of the shaft when the clutch is disengaged. A first portion of the assembly mounted for rotation with the flywheel includes a fluid cylinder, a piston and a pair of spring biased clutch plates which are axially displaceable by the piston. A second portion mounted for rotation on the drive shaft includes two spline plates and a brake plate and a double splined hub, the spline plates being axially slidable on the splines of the hub. The brake plate is normally biased into frictional engagement with a stationarily mounted brake. Actuation of the piston engages the clutch plates with the spline plates and disengages the brake plate.

Abstract: An inching control apparatus comprising a hydraulic pressure source, a plurality of clutches and, in a hydraulic circuit connecting the clutches to the hydraulic pressure source, a pressure regulating valve, an inching valve which receives output pressure from the pressure regulating valve for delivering inching control pressure, and a selector valve which receives control pressure from the inching valve for selecting engaging and disengaging the frictional engaging means. The inching valve delivers the output pressure from the pressure regulating valve directly when an inching pedal is not depressed by the driver's foot, and delivers a control pressure, which diminishes as the amount of pedal depression increases, when said amount of depression exceeds a predetermined amount.

Abstract: A propeller brake for an engine having a propeller shaft includes a housing (10) and a brake shaft (18) rotatably mounted in the housing (10). The brake shaft (18) is coupled to the propeller shaft to rotate therewith. Also included is a brake (64,74) and a lock device (38). The brake (64,74) is mounted in the housing (10) and has a spaced plurality of frictional plates (64) for frictionally resisting rotation of the brake shaft (18). This brake (64,74) is reciprocatable between an operative and an inoperative position. The lock device (38) is mounted in the housing (10) and can reciprocate between an unlocked and locked position. This lock device (38) can, in its locked position, inhibit rotation of the brake shaft (18). The forgoing equipment can stop a propeller shaft by first frictionally coupling the brake (64,74) to the propeller shaft, allowing the coupled portion of the brake (64,74) to rotate therewith. The brake (64,74) may then be actuated to transmit a resisting torque to stop the propeller shaft.

Abstract: A hydraulic circuit is disclosed for activating a clutch as well as a throttle valve which is used in the circuit. The hydraulic circuit includes a hydraulic actuator which is connected to a source of pressurized fluid to alternatively activate the clutch. Connected between the source of pressurized fluid in the actuator is a control valve and a pressure-responsive throttle valve. The control valve is basically an on/off valve which controls the flow of fluid to the clutch actuator or from the clutch actuator to a reservoir. The throttle valve, on the other hand, is arranged in series with the control valve and is responsive to fluid pressure on its downstream side to cause increased throttling of the fluid as the fluid pressure to the actuator increases. Such a circuit is beneficial in preventing the clutch from snatching as it is being engaged.

Abstract: A hydraulic circuit is disclosed for activating a clutch as well as a throttle valve which is used in the circuit. The hydraulic circuit includes a hydraulic actuator which is connected to a source of pressurized fluid to alternatively activate the clutch. Connected between the source of pressurized fluid in the actuator is a control valve and a pressure-responsive throttle valve. The control valve is basically an on/off valve which controls the flow of fluid to the clutch actuator or from the clutch actuator to a reservoir. The throttle valve, on the other hand, is arranged in series with the control valve and is responsive to fluid pressure on its downstream side to cause increased throttling of the fluid as the fluid pressure to the actuator increases. Such a circuit is beneficial in preventing the clutch from snatching as it is being engaged.