Abstract: A speed limiting accessory drive for use with an engine in a vehicle. A speed limiting drive pulley (16) is affixed to a crankshaft (14) via a hub (42) and includes a pulley member (24) which drives the accessory belt (18). A Clutch assembly (36) is operatively located between the hub and pulley member, with a piston (54) or bellows biased against and engaging the clutch assembly. Oil located throughout the clutch assembly is acted on by centrifugal force when the drive pulley is rotating and acts to push against the biases of the piston. This allows the clutch to slip at high engine speeds, thus limiting the speed of the pulley member. A heat compensating mechanism acts to counter the pushing force of the oil if the temperature of the oil rises too high due to the clutch slippage, thereby reducing clutch slip.

Abstract: A speed limiting accessory drive and crankshaft damper for use with an engine in a vehicle. A speed limiting drive pulley (16) is affixed to a crankshaft (14) via a hub (42) and includes a pulley member (24) which drives the accessory belt (18). A damper mass (40) is elastically attached to the hub via damper springs (44). A Clutch assembly (36) is operatively located between the damper mass and pulley member, with a piston (54) or bellows biased against and engaging the clutch assembly. Oil located throughout the clutch assembly is acted on by centrifugal force when the drive pulley is rotating and acts to push against the biases of the piston. This allows the clutch to slip at high engine speeds, thus limiting the speed of the pulley member. A heat compensating mechanism acts to counter the pushing force of the oil if the temperature of the oil rises too high due to the clutch slippage, thereby reducing clutch slip.

Abstract: A regulator valve (14) includes a valve spool (30) biased in a valve chamber (32) by control pressure whose magnitude is determined by operation of a variable force solenoid (42), first and second control areas (28, 26) exposed to friction element pressure. A shift valve (16) includes a spool having multiple control lands (66, 68), the position of spool determined by the state of an on/off solenoid (70). The shift valve produces high and low hydraulic pressure operative to open and close line pressure or a vent to a hydraulically-activated clutch.

Abstract: A viscous fluid coupling device is comprised of (1) an input member, (2) a rotor secured to the input member, (3) an output member having therein an inner space and mounted rotatably on the input member, (4) a partition plate, for dividing the inner space into an operating chamber and a reservoir chamber for storing therein an amount of viscous fluid, secured to the output member and having a passage for establishing a fluid communication therebetween, (5) a thermal response valve, for opening and closing the passage, provided on the output member, (6) a labyrinth, for transmitting the rotation torque from the input member to the output member via the viscous fluid, provided therebetween so as to be positioned in the operating chamber, (7) a pump device, for returning the viscous fluid to the reservoir chamber, formed between an outer periphery of the rotor and an inner surface of the output member, and (8) a bypass device, for the direct supply of the viscous fluid supplied from the reservoir chamber to the

Abstract: A fluid power transmission adapted for combination with an engine to drive auxiliary equipment thereto including a rotor arrangement for direct driving connection to the engine crankshaft and a housing assembly rotatably supported on the rotor arrangement and forming therewith a fluid drive circuit to be in driven relation therewith. A centrifugally-actuated valve is radially disposed in the fluid circuit in the housing assembly to remain closed at rotational speeds of the housing assembly less than a predetermined optimum speed and to yield in response to centrifugal forces created upon rotation of the housing assembly at greater speeds for fluid flow in the fluid circuit to create slippage of the housing assembly about the rotor arrangement to limit increases in the rotational speed of the housing assembly over the optimum speed. The housing assembly includes a pulley wheel by which the auxiliary units are driven generally constantly at the optimum speed for maximum efficiency.

Abstract: Speed and temperature responsive drive apparatus includes a friction clutch which may be interposed between a vehicle engine and its associated cooling system fan. The clutch is biased toward engagement by a conventional spring and also by a thermal spring. A bladder develops a centrifugal pressure upon rotation of the apparatus, which pressure relieves the biasing forces of both springs.

Abstract: A four wheel drive torque transfer mechanism with a hydraulic control system is switchable between two wheel drive and four wheel drive during running of a vehicle having an automatic transmission.When a two wheel drive mode of operation is selected, the hydraulic control system automatically actuates the torque transfer mechanism to provide a four wheel drive operation if a governor output responsive to vehicle speed, falls below a predetermined level, and to provide a two wheel drive operation if a governor output exceeds the predetermined level.

Abstract: An engine cooling fan driven through a viscous clutch and having a mechanically shearable drive element into the powered input of the viscous clutch which shears at a predetermined low torque level to prevent fan damage due to viscous clutch lockup and limits fan speeds to a relatively low torque level.

Abstract: In a transmission having input and output shafts drivingly connected by fluid pressure operated ratio establishing devices an improved centrifugally actuated valve is provided to disestablish the driving connection maximum angular velocity of the input shaft. The valve includes a sphere disposed in a stepped bore which sphere is spring biased to a closed position for normal operation and which shifts in response to centrifugal force to an open position in a fluid flow path thereby exhausting the drive establishing device and also being flushed of any contaminants.

Abstract: A fluid pressure operated clutch which transmits torque from an engine output shaft to a transmission input shaft, including a rotatable flywheel connected to the output shaft, an adapter connected to the flywheel for rotation with the flywheel, the adapter having a first annular plate with a fluid passage near the inner periphery of the plate, and a centrifugal piston which defines with the adapter a fluid chamber supporting a rotatable torus of hydraulic fluid. The piston has a second annular plate, slideable with respect to the first plate, and a second fluid passage near the outer periphery of the second plate. The first and second plates, at their inner peripheries, provide a controlled clearance to vary the rate of hydraulic fluid into the first fluid chamber as the second plate slides.

Abstract: Apparatus for preventing overspeeding of an engine is provided. In preferred embodiments, an hydraulically actuable clutch is controlled by a piston-cylinder arrangement connected to a driver operable clutch pedal. The rear side of the piston in this arrangement is selectively communicated with a high pressure air source and an exhaust space by means of a solenoid valve. The solenoid valve is controlled by a tachometer switch so that the same communicates the high pressure medium to automatically actuate the disengagement of the clutch whenever a predetermined set engine speed is exceeded. The pressure medium space at the side of the piston is also communicated with a further piston-cylinder arrangement for automatically forcing an engine accelerator pedal toward a no-load engine running condition at the same time the clutch is automatically disengaged. An emergency switch is provided for overriding the clutch disengaging apparatus so as to accommodate intentional usage of the engine as a brake.

Abstract: A two-stage, four-way valve has fluid input and output connections, and passes a fluid under controlled pressure to an actuator to operate any component. Such operation is sensed and, after comparison with a reference signal, a control signal regulates the duty cycle of a pulse-width modulation (PWM) circuit. The output square-wave signal from the PWM circuit regulates a solenoid incorporated in the valve, to modify its operation and regulate the pressure of the controlled fluid. The valve has a spool which effectively integrates the PWM signal and provides a type 1 servo system when connected in a closed loop system.

Abstract: An improvement in a drive transmission for coupling an engine to a driven load at any selected one of a plurality of drive ratios which comprises a gear section having an input shaft, an output shaft, a plurality of gears and shift devices for interconnecting said gears in any of a plurality of predetermined relationships, a fluid pressure operated input clutch for coupling said gear section input shaft to said engine having an engaged position and a disengaged position, a fluid perssure operated output clutch for coupling said driven load and said gear section output shaft having an engaged position and a disengaged position and an automatic operating control for selectively applying fluid pressure to said output clutch.

Abstract: A control valve for a fluid operated clutch or the like, including a valve body, a first valve mounted for reciprocation in the valve body, a second valve mounted for reciprocation in the valve body and for relative movement with respect to the first valve, one of the valves being concentric with the other, ports in the valves including a throttling port at the interface of the valves, a manual actuator for reciprocally shifting one of the valves, and a rotatable flyweight assembly for reciprocally shifting the other of the valves. Throttled fluid flow from the valve may be directed to a fluid operated clutch to control its capacity and regulate the output speed thereof.

Abstract: A multiratio powershift transmission having fluid operated drive devices including a forward clutch with an apply chamber supplied with fluid apply pressure to engage the clutch for forward drives and exhausted to disengage the clutch for reverse drive. The apply chamber is in a housing rotating at input speed during forward and reverse drive. In forward drive, a dump valve mounted on the rotating housing is biased closed by a spring, static fluid apply pressure, and centrifugal pressure head, in the rated input speed range. At a higher speed, centrifugal force on the dump valve element opens the dump valve to exhaust the apply chamber and disengage forward drive. In reverse drive, the dump valve is biased closed only by the spring which at idle speed closes the dump valve, and at a low speed used in reverse drive, centrifugal force opens the dump valve to flush the dump valve during reverse drive.

Abstract: In an automatic transmission apparatus for a vehicle of the type having a high speed clutch of oil pressure operated type interposed in a high speed power transmission system and a low speed clutch of oil pressure operated type interposed in a low speed power transmission system, the clutches being selectively connected through a shift valve to an oil pressure source, a safety apparatus comprising an automatic control valve coupled to the said low speed clutch to operate when the low speed clutch rotates above a predetermined speed to bring the low speed clutch into inoperative condition.

Abstract: A torque responsive coupling includes an intermediate coupling member with helical splines thereon selectively engageable with first and second axially spaced helically splined coupling discs connected respectively to an engine power shaft and to a gear reduction input shaft to a propeller.

Abstract: A constant speed drive system which is automatically controlled according to the load of the pump, fan, etc. driven by the system. Control of the system is achieved by means of a pump or compressor and a diaphragm-actuated spool valve, wherein a reference point or pressure in a spool valve is matched with a pressure, proportional to the speed of the load or output shaft, acting on a diaphragm in the spool valve. The spool valve, in turn, modulates the pressure to a clutch actuator for a clutch located between a constant speed motor and a shaft driving the requisite load.

Abstract: A machine comprising a rotary drive shaft and a pneumatically operated clutch: a plurality of pressure chambers to which air is supplied for controlling said clutch; means for varying the air pressure in one of said chambers corresponding to the speed of rotation of said shaft and comprising centrifugally controlled valve means mounted on said shaft for rotation therewith and connected to said one of said chambers to cause a build up of pressure in said one of said chambers corresponding to the rotational speed of said drive shaft.