Abstract: A fan fluid coupling for use with an automotive engine. The coupling comprises a sealed housing, a partition plate that partitions the inside of the housing into an oil reservoir chamber and a torque transmission chamber, a resilient tonguelike valve member, and a rod member. The partition plate is provided with an outflow-adjusting hole located close to the outer end of the partition plate. The hole is a slot extending circumferentially of the partition plate. One end of the valve member is fixed to the partition plate. The valve member is curved upward. The front end of the valve member is in resilient contact with the rod chamber against which a bimetallic strip is pressed.

Abstract: A fan drive clutch is provided which includes a fluid coupling for coupling a drive shaft and a clutch housing on which a fan for blowing air to a radiator is disposed. This clutch has a pump plate for defining a fluid reservoir chamber and a working chamber. The pump plate includes a valve opening through which working fluid passes from the reservoir chamber into the working chamber. The fan drive clutch further includes a valve arm which has a valve plate for opening and closing the valve opening. The valve arm includes an elastically transformable section at a connecting portion between it and the valve plate. This section is operable to absorb movement of the valve arm which may be caused due to a clearance between the shaft for supporting the valve arm and the bearing hole for rotatably supporting the shaft.

Abstract: In an automatic transmission, a hydraulic pressure control valve produces hydraulic pressure according to a pilot pressure fed thereto. A duty solenoid valve controls the pilot pressure. An oil temperature sensor detects the temperature of the hydraulic oil and a driving period changing circuit changes the driving period of the duty solenoid valve according to the temperature of the hydraulic oil so that the driving period is long when the temperature of the hydraulic oil is low and short when the temperature of the hydraulic oil is high.

Abstract: A fluid coupling includes a casing supported by a drive shaft, a cover fixed to the casing to form a chamber, a partition plate fixed to the cover to partition the chamber into a reservoir and an operation chamber, a rotor disposed in the operation chamber, a valve plate operated to open or close a passage provided in the partition plate, a stud supported by the cover and fixed to the valve plate and a bimetal spring fixed to the stud on an inner end and to the cover on an outer end thereof. A damper is disposed between the cover and the bimetal spring and includes a rubber block and a bracket fixed to a part of the cover. The damper prevents the vibration and breakage of the bimetal spring.

Abstract: A viscous fluid fan clutch assembly for a vehicle includes an internally-mounted pump plate for separating a working chamber from a reservoir. A plurality of pressure-sensitive fluid check valves are provided in the pump plate to permit only one-way fluid flow from a pumping chamber to the reservoir. Each check valve includes an interior chamber having a pair of angled side walls which terminate at a normally-closed outlet. When a predetermined fluid pressure is achieved in the pumping chamber, the side walls are forced apart to open the outlet. The closing of the outlet is not dependent upon fluid pressure in the reservoir.

Abstract: A fluid shear coupling comprises a driving member having a disc-shaped portion and a driven member defining a working chamber in which the driving member is received, the two members being mounted for relative rotation about a common axis, the driven member defining an annular groove facing the side of the driving member and further defining a circumferential cavity facing the outer perimeter of the driving member, and a one-piece, L-shaped dam having a radially extending portion received within the annular groove and an axially extending portion received within the circumferential cavity, each of the radially and axially extending portions including a first ramp surface facing in one direction and a second ramp surface facing in the other direction.

Abstract: Normally, fluid friction clutch having cup disks, in order to permit the circulating of clutch fluid in the relatively small cylindrical ring gap between the housing and the cup disk, must be provided with thread-type conveying grooves. According to the invention, these expenditures are avoided in that the cup disk, on its closed side, is provided with a surrounding edge which projects beyond the cylindrical circumferential surface radially toward the outside and which is flush with the front face of the cup disk. Radial grooves preferably lead into this edge and are provided at the front face. The cup disk preferably be combined with axially extending notches in the cylindrical ring surface of the housing and with conical openings by means of which an intense circulation of the coupling fluid is ensured. The clutch is to be used for the drive of fans for vehicle engines.

Abstract: A fluid coupling device is disclosed of the type including a valve plate (31) separating the fluid chamber into an operating chamber (33) and a reservoir chamber (35). The valve plate defines first and second fill openings (43a,43b), flow through which is controlled by a valve member (41) which rotates in the plane of the valve plate in response to variations in temperature. The first (43a) and second (43b) fill openings are disposed in generally the same region of the valve plate (31). The valve member (41) includes first (41a) and second (41b) port covering portions, disposed to cover the fill openings, when the valve member is in a disengaged condition, and to uncover the openings as the valve member moves toward an engaged condition. Having the fill openings in the same region of the valve plate substantially reduces the negative effects of errors in the concentricities of the valve arm, valve plate and the various parts of the device.

Abstract: A viscous fluid fan clutch assembly for a vehicle includes an internally-mounted pump plate for separating a working chamber from a reservoir. At least one fluid gate is provided in the pump plate to permit fluid flow from the reservoir to the working chamber. Only one discharge orifice is provided in the pump plate for permitting the return of fluid from the working chamber to the reservoir. Air vents are provided inbound of the discharge orifice to permit the passage of air between the reservoir and the working chamber. A check valve is mounted at the vent means to provide selective control of air through the air vents.

Abstract: A soft start, self-powered coupling for connecting a motor to a load, the coupling including a magnetic particle clutch, a generator having a rotor carried by the clutch and a stator, and an electronic control circuit assembly carried by the generator rotor, the magnetic particle clutch being connector to the motor and to the load, the generator powering the electronic control circuit assembly and the clutch to provide linear timed acceleration of the load.

Abstract: A locking synchronizer for transmission shifts, has a sliding sleeve carrier and a gear revolving at a different speeds of rotation coupled together upon attaining synchronism by means of an axially slidable, annular sliding sleeve. A coupling tooth array of the sliding sleeve (11) engages a corresponding spur gearing (11) of the sliding sleeve carrier (21) as well as a coupling tooth array (21) of the gear, with engagement pins positioned between the sliding sleeve carrier and sliding sleeve 3. Portions of the gear form with portions of the synchronizing ring a coupling capable of transmitting force and with locking teeth on the synchronizing ring for the temporary prevention of the axial movement of the sliding sleeve, whereby the preventive action is cancelled even during existing defference in speed of rotation as a function of the warming on the synchronizing ring or a defined unlocking force which acts transversely to the motion of the sliding sleeve on the locking teeth of the synchronizing ring.

Abstract: A fluid friction clutch is disclosed for vehicle cooling fans and the like, which clutch is controlled by a bimetallic element controlling a clutch fluid valve opening.Since the bimetallic element must have degrees of freedom, the fastening of the bimetallic elements at the cover of fluid friction clutch results in difficulties, particularly if the clutch is subjected to high stress. In order to avoid that the bimetallic element can move away from its position in the case of high stress, it is suggested to provide a bimetallic element which is clamped in only at one side and the free end of which has the required freedom of motion, but which can be fastened securely in its position. The new clutch is used for cooling fans of motor vehicle engines which are to be switched as a function of the temperature.

Abstract: A preload control arm for controlling fluid flow through a viscous fluid clutch includes a rotatable control shaft mounted in the clutch. The control arm is secured to the control shaft so that flexible end portions of the control arm cover pump plate orifices in the clutch. A spring secured to the control shaft provides a force adajcent the end portions opposite the pump plate orifices to maintain the seal when the control arm is in the closed position.

Abstract: A rotational speed differential type torque transmitting assembly includes a rotor rotatably disposed in a drive housing. During rotational speed differential between the rotor and drive housing, hydraulic fluid is discharged out of variable volume chamber on discharge stroke of the associated piston. Orifices are provided to restrict flow of hydraulic fluid discharged, inducing a pressure rise and adiabatic compression of the hydraulic fluid, causing heat build-up in the rotor. In order to prevent excessive rise in temperature of the assembly, a temperature responsive type spool valve is provided to close the orifice means in response to temperature rise of the hydraulic fluid in the rotor.

Abstract: A fluid-friction clutch with a temperature control is disclosed for the drive of a fan for the radiator of a motor vehicle engine. It is provided to arrange a shoe made of teflon in the contact area between the bimetallic strip and the ribs provided for the fastening, the bimetallic strip placing itself against this shoe. A durable securing of the position of the bimetallic strip can take place at this shoe.

Abstract: A rotary fluid coupling device is provided of the type including a first rotatable coupling assembly (13) comprising a housing member (15) and a die cast cover member (17). An input coupling member (11) is disposed in a fluid operating chamber (33) and cooperates with an adjacent surface of the cover member (17) to define a viscous shear space therebetween. When the shear space is filled with viscous fluid, torque can be transmitted from the input coupling to the output coupling, such torque transmission resulting in the generation of a substantial amount of heat adjacent the front surface of the cover member. The cover member (17) includes a generally annular portion (36) defining therein a reservoir chamber (35). Disposed within a recessed area defined by the annular portion (36) is a bimetal coil (45) which defines a coil circle C.

Abstract: Fluid friction clutches tend to operate discontinuously when the performance requirement is low and therefore the filling ratio in the working chamber is also low. This so-called "surging" is to be avoided. According to the invention, a forced guiding is provided for the clutch fluid from a front part of the working chamber into the rear part of the working chamber, and only then is the return flow provided to the storage chamber which is achieved by a sealing-off of the working chamber into these two areas by means of the clutch disk and by means of the arrangement of a fluid deflector with damming bodies at a part of the circumference. The resulting forced distribution of clutch fluid on both sides of the clutch disk permits a smooth operation of the clutch and, when pumping elements are arranged, also a reduction of the hysteresis. Fluid friction clutches of this type are particularly suitable for fan drives for cooling devices of motor vehicles.

Abstract: A fluid coupling for an engine cooling system includes a driving member rotationably coupled to a driven member by a viscous fluid coupling. The viscous fluid coupling is controlled to vary the torque transfer from the driving member to the driven member as a function of a sensed engine liquid coolant temperature.

Abstract: Dispersion of eutectic material (56) in a thermal disconnect coupling following thermal actuation is avoided by disposing the body (56) of eutectic material in a first axially opening cavity (40) in a driven shaft (24) having teeth (32) normally meshed with teeth (22) on a driving shaft (16). The first cavity (40) is closed by a wall (50) forming part of an output shaft (26) and the interface of the cavity (40) and the wall (50) is provided with seals (92, 94). The first cavity (40) is separated from a second cavity (42) in the driven shaft (24) by a perforated web (44, 46) and together with an element (60) supported by the output shaft (26) defines second chamber into which the body (56) may flow upon thermal actuation. The interface of the element (60) and the second cavity (42) is provided with seals (92, 94) to prevent the escape of eutectic material from the second chamber.

Abstract: A temperature-operated fluid friction coupling is actuated by a flow of viscous fluid flowing into or out of shearing surface gaps disposed therein. The coupling of the invention includes an additional valve opening penetrating a partition and an additional valve lever mounted on the partition. The additional valve lever is made of a bimetallic element or bidirectional shape memory alloys such that it curves at a considerably low temperature near the standard ambient temperature, allowing the second valve opening to open and close. Thus, the fan idling speed during OFF condition of the coupling can be set considerably low in comparison with conventional designs.

Abstract: A thermosensitive hydraulic fan coupler for an automobile engine, which allows a suitable amount of air to be supplied to the engine in accordance with the travelling condition of the automobile through the rotation of a fan is provided. The fan coupling according to the present invention is provided with an idle oil chamber and a specific dam within the former adjacent the oil circulation passage between the oil chamber and the torque transmission chamber with the dam serving as an opening and closing mechanism so that in addition to the effects of preventing the generation of abnormal fan noises and promoting an warming-up operation of the engine, it can more effectively prevent the phenomenon of "attendant rotation" of the driven side of the coupling immediately after restarting the engine.

Abstract: A fan clutch assembly for a vehicle includes a clutch plate rotatably driven by an input shaft. The clutch plate includes a plurality of concentric, annular lands and grooves which are mated with complementary lands and grooves of a clutch body to form a shear zone. A plurality of passages are provided in the clutch plate lands and grooves for directing fluid from a reservoir to the shear zone. A plurality of radial channels are provided in the clutch plate lands and grooves to expel fluid from the shear zone to a receiving chamber of the clutch plate assembly. Each channel is aligned with and leads radially outwardly from a respective passage. Preferably, each groove includes an aligned notch provided on the circumference of the clutch plate. The notch includes a mouth on the surface of the clutch plate adjacent the lands and grooves and an exit on the surface of the clutch plate adjacent a receiving chamber.

Abstract: A fan clutch assembly for a vehicle includes a pump plate for separating a collecting chamber and a receiving chamber from a reservoir. The pump plate includes a plurality of orifices for permitting the passage of fluid from the receiving chamber to the reservoir. A dual face wiper having scoop surfaces on each lateral side is mounted on the pump plate adjacent respective orifices to permit either clockwise or counterclockwise rotation of the fan asssembly.

Abstract: A fan clutch assembly for a vehicle includes a pump plate assembly for separating a receiving chamber from a reservoir, wherein the receiving chamber receives fluid from a shear zone. The pump plate assembly includes an orifice for permitting the passage of fluid from the receiving chamber to the reservoir. A check valve is provided at the orifice to control the flow of fluid and permit only one-way flow from the receiving chamber into the reservoir. The check valve eliminates the migration of fluid through the orifice from the reservoir into the receiving chamber.

Abstract: The invention relates to a viscous fluid variable drive to a rotary cooling fan for an engine, the drive being automatically controlled in response to sensed parameters such as temperature. In one example the drive unit includes an inner drive member 14 within a casing 10, 11 which includes a pump 24 continuously delivering fluid from the gap to a central valve port 25 when the fluid returns to a reservoir 20 and then spills through an aperture 26 back into the clearance gap. The valve port 25 in the supply passage from the pump is automatically controlled by a valve 30 actuated by compressed air in a line 36 from a remote thermal sensing unit. In another embodiment the valve 30 is controlled by a bi-metal strip 46 sensitive to ambient air. The pressure from the pump may also be used to actuate a servo valve 61 controlling tbe return flow of fluid from the reservoir 20 to the clearance gap. The valve may be in two separate units controlled spearately by valve elements 101 and 30'".

Abstract: A fluidized fan coupling device is provided to substantially eliminate accompanying rotation followed engine start up. The device includes a sealed housing with a partition plate dividing the interior of the housing into a torque transfer chamber and an oil reservoir. The housing is rotatably mounted to a shaft which extends into the torque transfer chamber. A driving disk is mounted to the shaft and is disposed in the torque transfer chamber. An oil outflow regulating hole extends through the partition plate and is provided with a valve that responds to changes in temperature. The partition plate also has an oil circulating aperture to permit flow of oil from the torque transfer chamber to the oil reservoir only when the engine is stopped. An idle oil groove in the outer periphery of the torque transfer chamber communicates with an oil circulation passage which extends from the idle oil groove to the oil reservoir. A dam is provided in the idle oil groove to urge the oil through the oil circulation passage.

Abstract: An automotive type internal combustion engine driven accessory is connected to the engine crankshaft by a thermal and centrifugally responsive clutch mechanism that includes a centrifugally responsive ring responsive to higher engine speeds to provide slippage between the clutch parts to maintain the accessory drive at a predetermined maximum RPM, that speed level being increased in response to an excessive generation of heat due to the slippage to effect a greater engagement of the clutch and less slippage and therefore a reduction in the amount of heat generated.

Abstract: A fluid shear coupling apparatus including a driving member comprising a rotor mounted to a shaft. A driven member including a bearing housing is mounted to the shaft. A complementary surface between the driven member and the driving member is provided between which a shear fluid provides variable coupling according to the proportion of fluid in the reservoir vis-a-vis the fluid shear chamber defined by the complementary surface. A temperature responsive valve is provided to modulate the shear fluid level. The valve may modulate an overlapping inlet having a constant area. An overlap inlet may be define by an arcuate slot or by a fixed size valve aperture. The valve may be pivotable on a valve axis which is eccentric to, and radially outward of, the common axis of the driving and driven members. Temperature responsive rotation of the valve member may be provided by coupling links or by gearing mechanism.

Abstract: A fluid coupling apparatus has a three stage control for torque transmission. The apparatus has two slots, of which one slot is opened when the temperature reaches a first set temperature. The other slot is opened at a second set temperature. The latter slot has a shape which increases the opening gradually in accordance with the movement of a valve member so that the torque transmission is gradually increased from the second torque transmission state to the third torque transmission state.

Abstract: A viscous fluid clutch for driving a cooling fan 18 from the crankshaft of an internal combustion engine includes an outer rotary casing 11, 12 connected to the fan and an inner rotary member 10 connected to the crankshaft coupling 9. The clearance gap between these two members is normally occupied by a viscous fluid and the drive is automatically adjusted by varying the quantity of fluid in the gap. A scoop pump 22 continuously pumps fluid from the gap inwards along passage 24 to a reservoir 20 via control valve 50, and the fluid returns to the clearance gap from the reservoir via a port 26. The valve 50 includes a piston 61, which is subject on one side of the pressure of the fluid supplied by the scoop pump 22, and hence to the relative speed of rotation between the crankshaft and the fan. In the other direction the piston 61 is subject to the fluid servo pressure in a conduit 48 derived from the sensed temperature of the engine coolant in duct 40.

Abstract: A viscous fluid coupling device especially is used for driving the cooling fan of engines and for controlling the rotation speed of the fan smoothly according to the temperature. The smooth change of torque transmission by the coupling device is performed by employing a specially shaped slot for fluid passageway. The increase rate of the opening area of the slot is smaller in a low temperature region than in a high temperature region.

Abstract: A fan fluid coupling for controlling the rotational speed of a fan that cools an automobile engine. The coupling comprises an enclosed housing, a partition plate that divides the inside of the housing into an oil reservoir chamber and a torque transmission chamber, a driving disk, a dam, a passage extending from the torque transmission chamber to the oil reservoir chamber, a bimetallic strip, a valve member, an idle oil reservoir chamber, and a circular hole formed in the driving disk for placing the idle oil reservoir chamber in communication with the torque transmission chamber only when the associated engine is at rest. At least one small hole is formed in the wall defining the idle oil reservoir chamber, and this hole is in communication with the torque transmission chamber.

Abstract: A temperature-sensing fan fluid coupling for use with an automobile engine. The coupling comprises a sealed enclosure, a partition plate having an outflow control hole, a thermostat mounted upon the front surface of the enclosure, a rodlike link member in contact with the thermostat at its one end, an interlocking member against which the link member bears, and a resilient tonguelike valve member. One end of the valve member is fixed, while the other end is in resilient contact with the front end of the interlocking member. The thermostat is connected to the valve member via the link member and the interlocking member. As the ambient temperature changes, the thermostat deforms to cause the valve member to more or less open the hole.

Abstract: An original, replacement, or aftermarket mechanism which responds to predetermined maximum torque levels to decouple a radiator fan from the rotation of a driving element, usually a water pump. The mechanism includes variable mounting adaptations which can accommodate water pumps and fans of different lengths, diameters and required physical location so that a large number of vehicular applications can be satisfied with a few different size fan clutch mechanisms. The mechanism includes a rotor case connected to the fan and a rotor connected to the water pump. The rotor is positioned in a cavity in the case and is immersed in nonlinear fluid such as silicon fluid.

Abstract: To incorporate a viscous coupling type power transmission apparatus for a four-wheel driven automotive vehicle with an antiskid braking system, viscous torque transmission from a first rotary transmission shaft (coupled to the front wheel shaft) to a second rotary transmission shaft (coupled to the rear wheel shaft) is intermitted by a clutch mechanism provided for the power transmission apparatus whenever a foot brake is applied. That is, when a foot brake pressure is applied to the brake member of the power transmission apparatus, the clutch mechanism is disengaged via a cam ring to decouple the first rotary transmission shaft from the second rotary transmission shaft.

Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or driving a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fluid flowing therethrough.

Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or drivig a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fliud flowing therethrough.

Abstract: An electromagnetic clutch according to the invention includes a first rotatable member having an axial end plate of magnetic material and a second rotatable member. The second rotatable member includes a drive shaft, and a hub mounted on an end of the shaft. An annular armature plate is disposed on an outer peripheral portion of the hub facing the axial end plate of the first rotatable member with an axial air gap therebetween. An electromagnetic device is disposed within the first rotatable member for attracting the armature plate to the axial end surface of the first rotatable member. The armature plate is elastically connected with the hub by a plurality of leaf springs and is made of materials with a low Curie point. Meltable elements are disposed on the armature plate to define the axial air gap between the first rotatable member and the armature plate.

Abstract: A fan clutch assembly for a vehicle includes an electromagnetic control assembly for actuating a rotatable valve plate. A rotatable shaft is connected to the valve plate. A ferromagnetic element is slidably mounted on the shaft. When an electromagnetic coil is energized, the resulting flux attracts the ferromagnetic element. As the ferromagnetic element slides, it is rotated to cause rotation of the shaft, thereby opening the valve plate.

Abstract: A viscous fluid coupling for use with a fan that cools as automobile engine includes a rotor driven by the engine. The rotor is housed in a housing formed by a case and a cover. A rear plate is mounted on the inner surface of the case and has an orifice. A front plate is mounted on the inner surface of the cover and has a hole through which viscous fluid can flow. A first reservoir is formed by the cover and the front plate. A second reservoir is formed by the rear plate and the case. Teeth are formed on the outer surface of the rotor. A protrusion is formed on the outer periphery of the rotor near the orifice.

Abstract: This viscous fluid fan drive clutch has a chamber divider and flow control ring at the face of the clutch plate which prevents fluid bypass of the shear zone and features flow blocker arms depending from the ring which fit within fluid fill passages in the clutch plate to tailor the response time of the clutch.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within a truck or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (106) defined by complimentary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving element (196) within the clutch to control the torque transmission there through and thus the speed of the output shaft and fan (34) thereof. Fan speed is regulated by variable current signal applied to a coil (174) within assembly (30) to selectively variably frictionally engage valve element assembly (196) with a grounded thrust surface or reaction member (190) to effect limited displacement of a valve element (198) in response thereto.

Abstract: A temperature activated fan assembly preferably for an electric motor. The assembly includes a fan, a torque transfer means engagable with the fan for transferring torque to the fan and a first member which expands in response to a temperature increase. The expansion of the first member causes the torque transfer means to engage the fan. The first member is situated within the motor such that the first member causes the fan to operate when a critical temperature in the motor is reached. The first member can be fabricated as a rod or coil from a material having a suitably high coefficient of thermal expansion. The first member can also be fabricated from a memory material.

Abstract: A temperature-sensitive fan-coupling apparatus is provided with a driving side and a driven side. The driving side comprises a tightly sealed housing. The driven side comprises a rotary member from which fan blades extend. The rotary member includes a following disc disposed in the housing with a torque transmission gap existing between the following disc and the housing. A partition plate is mounted to the rotary member to define an oil reservoir therebetween. An aperture extends through the partition plate to provide communication between the oil reservoir and the torque transmission gap. A temperature-sensitive member is mounted external to the driven end of the apparatus and to one end of a connecting rod which extends through the rotary member and into the oil reservoir.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within a truck or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (106) defined by complimentary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving element (196) within the clutch to control the torque transmission there through and thus the speed of the output shaft and fan (34) thereof. Fan speed is regulated by variable current signal applied to a coil (174) within assembly (30) to selectively variably frictionally engage valve element assembly (196) with a grounded thrust surface or reaction member (190) to effect limited displacement of a valve element (198) in response thereto.

Abstract: A valve member of a temperature sensitive fluid fan coupling for an engine cooling fan is formed from a plate material having a weight provided at its free end. The modulus of section of the longitudinally central portion of the plate material is reduced to impart flexibility thereto so that it is flexible in the direction of rotation. Accordingly, it is possible to enhance the effect of the action of the weight which causes the valve member to be displaced so as to cancel the pivotal displacement of the valve member caused by the displacement of a bimetal. Thus, it is possible to eliminate the discontinuity in the temperature sensitivity of the speed of rotation of the fan and hence lower the noise level, reduce the fuel consumption and minimize the change in temperature of cooling water.

Abstract: A differential apparatus comprises first and second rotary devices rotatable with respect to each other, a viscous clutch having a chamber filled with a viscous fluid and restricting a differential operation generated between the first and second rotary devices by the resistance of the viscous fluid, a friction clutch separated from the viscous clutch and restricting the differential operation, and a device for preventing the seal of the chamber from being reduced by an increase in pressure within the chamber and actuating the friction clutch in accordance with an input torque.

Abstract: A joint device according to the present invention is attached to each of a plurality of arm units which constitute an arm of an industrial robot, and is used to connect a first arm unit and a second arm unit adjacent thereto, and to rock the arm units. The joint device comprises a coupling mechanism which connects the first and second arm units for rotation around specified axes. A first gear train, which includes a plurality of gears, is provided in the first arm unit, and has a rotatory-force transmission path through which the gears thereof successively transmit a rotatory force. A first rotatory-force source is used to transmit the rotatory force to the first gear train. The second arm unit is constructed in the same manner as the first arm unit. A clutch mechanism serves to permit and interrupt the transmission of the rotatory force through the rotatory-force transmission path of the first gear train.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within in a truck or or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (100) defined by complementary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving member (158) within the clutch to control the torque transmission therethrough and thus the speed of the output shaft (and fan 34) thereof. Fan speed is regulated as a function of a sensed temperature of the host engine by a control circuit (176) which senses fan speed and coolant fluid temperature and generates a speed error signal as a function of temperature.

Abstract: A fluid friction clutch is provided having a disk and a housing concentrically surrounding the disk, with a working gap formed between the housing and the disk. The housing has a collecting channel for return of clutch fluid from the working gap to a storage chamber. Clutch fluid flows to the collecting channel due to the arrangement of grooves located in axially adjacent groove sections. The collecting channel is axially interposed between the groove sections, and the grooves are sloped so that the clutch fluid flows towards the collecting channel.