Abstract: A torque transmitting power train for use in a motor vehicle employs a transmission with two adjustable pulleys and an endless flexible element trained over the pulleys. The pulleys are adjustable by a torque sensor and primary hydraulic adjusting units in dependency upon the magnitude of transmitted torque, as well as by an adjustable selecting valve and secondary hydraulic adjusting units in dependency upon the desired or required transmission ratio. The primary and secondary adjusting units can receive a pressurized hydraulic fluid from a common source.

Abstract: An electronically controlled hydraulic apparatus for a belt drive type continuously variable transmission comprises a belt wound around a primary pulley and a secondary pulley, a line pressure control valve for controlling a line pressure of a secondary cylinder, a shift control valve for controlling a primary pressure of a primary cylinder. The shift control valve includes a pilot valve for generating a pilot pressure according to a solenoid current, a spool with a step and a valve body. The pilot pressure is applied to one end of the spool and the primary pressure feedbacked and a spring force are applied to the other end so as to control the primary pressure on the balance of the spool in the valve body. The step ratio of the spool is designed so as to be 1.11 to 1.5 and further the shift control valve is constituted such that the pilot pressure becomes near zero when the primary pressure is zero.

Abstract: In order to optimize the speed change control of a continuously variable transmission, a necessary minimum primary pressure (Ppmin) for achieving a target speed change ratio is computed, and also a necessary minimum line pressure (Plmin) for the non occurrence of slippage between a secondary pulley 5 and a belt 6 is computed, and a required speed change ratio line pressure (Plratio) which can realize a target speed change ratio without slippage on the primary pulley 4 side is computed. The highest of these is then selected. The selected line pressure (Pl base) is then corrected by a transition line pressure (Pl add) determined from engine torque (TQ.sub.ENG) and speed change speed (SV), to obtain a final output line pressure (Plprs) which is then used to control a secondary pulley actuator 5a. In this way, speed change control can be optimized, for example by controlling slipping of the belt 6 at the time of rapid speed change.

Abstract: A hydromechanical torque sensor having several plenum chambers can be utilized to transmit torque between the driving and driven parts in the power train of a motor vehicle as well as to make necessary adjustments in a hydraulically adjustable transmission. To this end, the plenum chambers of the torque sensor can be connected to or sealed from each other. The torque sensor and the transmission can receive fluid from discrete sources or from a single source by way of suitable valves.

Abstract: The invention relates to a method for influencing the tension in a drive belt in a continuously variable transmission. According to the invention, the tensions in the drive belt are determined as a function of the speed of the drive belt. For part, parts or the entire range of the possible input speeds of the transmission, the input speed of the transmission is then increased and/or reduced to a desired speed range for the drive belt with an essentially relatively lower tension in the drive belt. The power density, the efficiency and the control range of the transmission can be improved by application of this method.

Abstract: Pulley, in particular for a continuously variable transmission. The pulley is provided with two discs on a pulley shaft, at least one disc being axially movable relative to the other disc by means of control means. The movable disc is connected to the pulley shaft by means of a key/groove connection. A radially inward profile of the key/groove connection is connected to the disc, and a radially outward profile of the key/groove connection is connected to the shaft.

Abstract: A valve body assembly for an automatic transmission formed by superimposing and clamping a torque converter casing, a first separation plate, a main valve body, a second separation plate, a second valve body, a third separation plate and a servo body. Pairs of first separation plates and pairs of second separation plates are provided, one pair for 7-position types of automatic transmissions and another pair for 6-position types of automatic transmissions and are, respectively, selected, used and assembled between the converter casing and main valve body and the main valve body and second valve body depending upon whether a 7-position type of transmission or a 6-position type of transmission is being assembled. Thus, general purpose properties are provided to the valve body assemblies used in hydraulic pressure control systems for 7-position type and 6-position type automatic transmissions for vehicles and the like.

Abstract: A multi-speed transmission is provided which employs inflatable diaphragms to alter drive ratio. Particularly applicable to bicycles, the transmission is composed of a diaphragm mounted at the pedal axis and another mounted at the drive wheel axis, with a nylon drive belt connecting the two. These diaphragms are each inflated and deflated by way of pressurized cylinders mounted on the bicycle. Pedaling of the bicycle turns the pedal axis diaphragm which, in turn, drives the rear wheel diaphragm via a nylon drive belt. Pressure tubes carry the pressurized fluids from each of the cylinders to their respective diaphragm. Standard shifter mechanisms are used each of which, when moved, moves a piston within one of the cylinders, changing the pressure in that cylinder and the inflation of its respective diaphragm.

Abstract: A power train for use in motor vehicles has an infinitely variable transmission with two adjustable sheaves, an endless flexible torque transmitting element trained over the sheaves, and at least one hydraulic adjusting unit for each of the sheaves. The adjusting units receive pressurized fluid from a pump and the pressure of such fluid, and hence the extent of frictional clamping engagement between the sheaves and the flexible element, is regulated by a torque sensor including a plenum chamber with an outlet having an effective cross-sectional area which is variable in dependency upon variations of torque being applied to the torque sensor by the engine of the vehicle. The energy of fluid leaving the plenum chamber is used to operate a jet pump which draws fluid from a source for lubrication and/or cooling of the transmission and/or one or more clutches forming part of the power train.

Abstract: A pulley thrust pressure control apparatus for a belt-type continuously variable transmission comprises a pulley thrust pressure valve unit 40 for setting a low pulley thrust control pressure and a high pulley thrust control pressure greater than the low pulley thrust control pressure; a shift valve 53 for supplying the low and high pulley thrust control pressures selectively into drive and driven cylinders 14 and 19 of drive and driven pulleys in correspondence with the position of a spool thereof; a drive pressure feedback passage 39c for causing the pressure inside the drive cylinder 14 to act on the spool as a positional control force; and a driven pressure feedback passage 39d for causing the pressure inside the driven cylinder 19 to act as a positional control force on the spool in the direction opposite of that cause by the pressure from the drive pressure feedback passage.

Abstract: A device is proposed to determine the rotational speed of a transfer element (3) arranged in variable-diameter pulleys (1, 2) of a continuously variable transmission system, the said device Consisting of a sliding stock (4, 15), with a sensor (10, 16) which is supported on the transfer element (3) on the inner sides of the variable-diameter pulleys, which sliding stock is connected to the transmission case (8) by a spring (6) loaded rocker arm (5) mounted in a swivelling joint (7).With the knowledge of the peripheral speed of the transfer element (3), the rotary speeds (N1, N2) of the set of variable-diameter pulleys (1, 2) and the effective transmission radii (r1, r2), the slippage can be determined between the transfer element (3) and the sets of variable-diameter pulleys (1, 2).

Abstract: A pulley device for a continuously variable transmission includes a shaft having first and second ends, the second end being formed with two axially separated ring grooves. A C-shaped ring is engaged with one of the two ring grooves disposed near to a movable conical plate. A ring-shaped retainer is arranged to restrain radial movement of the C-shaped ring. A snap ring is engaged with the other of the two ring grooves to restrain an axial position of the retainer.

Abstract: A continuously variable transmission of an automotive vehicle has a start assist device, a forward-reverse changeover device, and a V-belt type transmission. The changeover device has an input shaft for receiving power from the start assist device. The V-belt type transmission has a drive shaft connected to a drive pulley. The input shaft and the drive shaft are aligned along a common longitudinal central axis. A fluid passage arrangement for the transmission includes a hydraulic fluid passage for a chamber of the drive pulley, which passage includes mutually communicating axial holes formed in the input shaft and the drive shaft. One of the axial holes communicates with a hydraulic fluid supply, while the other axial hole communicates with the chamber. The fluid passage arrangement further has lubricating fluid passages for the transmission and the changeover device.

Abstract: A process to adjust the pretensioning force for the transmission element of a continuously variable transmission, complete with two disc assemblies comprising two discs each, will be described. For optimized specification of the pretensioning force, the following process steps will be provided:a) determining transmission element length,b) specifying a start value for the pretensioning force,c) reducing the pretensioning force and determining transmission element virtual length,d) determining transmission element slip status by comparing actual length and virtual length of the transmission element,e) changing pretensioning force in relation to slip status, whereby, if actual length and virtual length of the transmission element correspond, the pretensioning force will be decreased, and, if actual length and virtual length of the transmission element differ, the pretensioning force will be increased.

Abstract: The present invention provides a radial drive connection between a movable flange and the shaft of an adjustable pulley. Specifically the movable flange is driven through the use of supports fixed to the shaft which radially fix the movable flange while allowing for axial movement. The supports are provided through a rigid disc splined to the shaft. The disc has an annular extension extending therefrom. Attached at one end to the disc and at the opposite end to the extension is at least one guide. Each guide includes a bolt or pin and an annular sleeve. The movable flange is configured to have a foot which has an annular wall to it. Through this wall the movable flange slidably engages the guide and provides a radial drive connection. Because the wall and guide slide, however, the movable flange is permitted to move in the axial direction.

Abstract: A supercharging device including an actuator for controlling return force of a resilient member in a continuously variable transmission (CVT) with a flyweight and a resilient member is provided. The actuator is employed so that a movable flange slides along the axis thereof away from a fixed flange in a drive pulley of the CVT when under a light load for which auxiliary machinery such as a supercharger driven by the CVT requires little driving force. The actuator is installed inside an input pulley through which the driving force of the engine is transmitted to the drive pulley.

Abstract: A control system for a continuously variable sheave drive having a driving sheave assembly (124) and a driven sheave assembly (126) connected drivably by a torque transfer belt or chain (144), each sheave assembly being comprised of a pair of friction drive sheave portions (128/130 and 178/180) that are axially adjustable, one with respect to the other, to establish varying pitch radii, each sheave assembly having a fluid pressure operated servo with a pressure chamber (164/212) supplied with control pressure from a pressure source, distribution of control pressure to one servo assembly effecting a pitch radius adjustment thereby changing the overall drive ratio, control pressure distribution to the other sheave assembly resulting in a clamping force, and valve means for limiting the rate of delivery of pressurized fluid to the ratio controlling sheave assembly (124) so that control pressure will not fall below a desired value.

Abstract: A pulley device includes a moveable conical pulley component which is moveable to a stationary conical pulley component by a servo motor. The servo motor includes a cylinder fixedly held with respect to a shaft portion of the stationary conical pulley component, and a piston fixed to the moveable conical pulley component and slidably engaging the cylinder. The servo motor also includes an auxiliary cylinder reduced in diameter than the cylinder and fixed with respect to the shaft portion, and an auxiliary piston fixed to the moveable conical pulley component. The auxiliary piston is received in the auxiliary cylinder.

Abstract: An electronically controlled continuously variable transmission system is provided with a driving belt trained over a primary and secondary pulley. The primary pulley is provided on a primary shaft and the secondary pulley is provided on a secondary shaft. Each pulley has corresponding spaced, conical pulley halves and at least one of the corresponding pulley halves is axially movable by respective primary and secondary moving devices. The transmission further includes a primary electronic control system for controlling the transmission ratio and a secondary electronic control system for controlling the belt tension. The primary electronic control system permits the operator to select from fuel economy, sporting, and maximum comfort performance modes. The primary electronic control means controls the transmission ratio in accordance with the performance mode selected. The moving devices include standby operating valves to permit continued operation of the transmission in case of power failure.

Abstract: A belt-type continuously variable transmission has a drive pulley coupled to an input shaft, a driven pulley coupled to an output shaft, a V-belt trained around the drive and driven pulleys, a drive-pulley cylinder for varying the pulley width of the drive pulley, and a driven-pulley cylinder for varying the pulley width of the driven pulley.

Abstract: In a pulley unit of belt-type continuously variable transmission, wherein a movable sheave on a pulley shaft is moved toward and away from a stationary sheave by means of a hydraulic servo device, and a movable cylinder secured to the movable sheave defines a hydraulic chamber between itself and a stationary plunger on the pulley shaft. The movable cylinder is of a ring-shape having an enlarged-diameter cylindrical portion, a reduced-diameter cylindrical portion, and a back wall portion integrally joining the two cylindrical portions radially. The reduced-diameter cylindrical portion is fitted on a hub of the movable sheave. A detachable cover member is provided around the cylinder and the plunger to define a hydraulic balance chamber. The movable sheave can be used commonly for different sizes of the movable cylinder, and the interior of the servo device can be exposed for maintenance by removing the cover member.

Abstract: A control apparatus for a hydraulically operated vehicular transmission has a plurality of hydraulic engaging elements including a first hydraulic engaging element which is kept engaged in a plurality of transmission trains. The control apparatus has an accumulator which is connected, via a branched oil passage, to a working oil passage which is communicated with the first hydraulic engaging element. It also has a control valve which is disposed in the branched oil passage and which can be moved between a first position in which an upstream portion of the branched oil passage on a side of the first hydraulic engaging element and a downstream portion of the branched oil passage on a side of the accumulator are brought into communication with each other and a second position in which the communication is shut off. It further has an oil discharge passage which is connected to a second hydraulic engaging element when the second hydraulic engaging element is disengaged.

Abstract: The present invention provides a radial drive connection between a movable flange and the shaft of an adjustable pulley. Specifically the movable flange is driven through the use of supports fixed to the shaft which radially fix the movable flange while allowing for axial movement. The supports are provided through a rigid disc splined to the shaft. The disc has an annular extension extending therefrom. Attached at one end to the disc and at the opposite end to the extension is at least one guide. Each guide is made from a bolt or pin and an annular sleeve. The movable flange is designed to have a foot which has an annular wall to it. Through this wall the movable flange slidably engages the guide and provides a radial drive connection. Because the wall and guide slide, however, the movable flange is permitted to move in the axial direction.

Abstract: The variable speed transmission is for transmitting a torque produced by an engine to a belt. The transmission comprises a shaft connected to the engine, a fixed flange and a movable flange slidably connected to the shaft and substantially rotatable thereon. The flanges define therebetween a groove for receiving the belt. A pressure device is rigidly connected to the movable flange. The pressure device has a pair of pressure units diametrically opposed for pressurizing fluids. Each pressure unit comprises a first fluid chamber, a second fluid chamber, a radially movable partition separating the first fluid chamber from the second fluid chamber, resilient means for applying a return force toward the shaft counterbalancing the centrifugal force, and a fixed partition rigidly connected to the shaft. The fixed partition also separates the first fluid chamber from the second fluid chamber.

Abstract: A continuously variable transmission control system having adjustable driving and driven sheave assemblies (124,126) connected drivably by a torque transfer belt or chain (144), each sheave assembly having a fluid pressure operated servo with a pressure chamber, distribution of control pressure to one servo (150,158,162) effecting a transmission ratio adjustment, control of pressure distribution to the other servo (202,210) resulting in a clamping force, a ratio control valve (246) for controlling distribution of pressure to the ratio controlling servo to effect upshifts and downshifts, provision being made for stabilizing the ratio control valve by providing for flow entry to the ratio control valve that is unrestricted, flow distribution to the ratio controlling servo having a controlled restriction whereby stability of the ratio control valve is achieved, fluid displaced from the ratio controlling servo being adapted to circulate through the ratio control valve to the inlet side (372) of the control system

Abstract: A cone disc transmission is presented which is infinitely adjustable and includes the production of axial pressure forces of the cone discs on pulling member rotating between these cone discs via hydraulic tensioning member. The tensioning member, which are arranged on the transmission shafts, each axially influence one of the cone discs which are displaceably arranged on the respective transmission shaft. By way of a control valve, the tensioning member and the pressure medium conduits connected thereto are charged by a pressure medium which is supplied by a pump. A torque disposed on the drive shaft of the transmission in the reflux of the control valve throttles the reflux of the pressure medium as a result of the torque-dependent movement of two valve members relative to one another and as a function of the load and thus determines the basic pressure of the system.

Abstract: In a continuously variable transmission which is provided with a primary pulley and a secondary pulley, between which a driving belt is mounted, primary and secondary control systems, which are coupled to the respective pressure chambers of the axially translatable pulley discs, are employed to precipitate current pressure values, in dependence upon desired pressure values. To this end, the control system employs a regulator to which only the difference between the desired and the measured pressure-value is supplied, whereby the regulator nevertheless only has to regulate the relatively rapidly changing variation in a rest value supplied separately by a rest state device. This greatly improves the dynamic behaviour of the controller, so that rapid variations in the desired value of the entrant pressure can be effectively followed by the control system.

Abstract: A supercharging device for an internal combustion engine includes a runner for compressing air, a driven pulley for rotating the runner, and a drive pulley for rotating the driven pulley. The drive pulley has a fixed sheave and a movable sheave movable in an axial direction with respect to the fixed sheave. A belt is wound around the driven pulley and the drive pulley. A control device is for moving the movable sheave in an axial direction so that the movable sheave is moved away from the fixed sheave under a low load condition and that said movable sheave is moved towards the fixed sheave under a high load condition.

Abstract: A hydrostatic continuously variable transmission includes a closed hydraulic circuit comprising a hydraulic pump, a hydraulic motor, and an oil supply passage connected between the hydraulic pump and the hydraulic motor. The hydraulic pump selectively generates a first oil pressure lower than a first predetermined pressure level, a second slowly-changing oil pressure higher than the first predetermined pressure level when the transmission is in normal operation, and a third rapidly-changing oil pressure higher than a second predetermined pressure level higher than the first predetermined pressure level when the transmission starts to operate.

Abstract: A control system for an automatic transmission of an automotive vehicle is provided. This control system includes a forward speed holding valve which is arranged in a hydraulic line communicating between a manual selector valve and a reverse frictional element such as a low and reverse brake, and has a first valve position which establishes fluid communication between the manual selector valve and the reverse frictional element to supply the hydraulic pressure from the manual selector valve to the reverse frictional element and a second valve position which blocks the fluid communication therebetween. When a selector lever is shifted to a reverse position while a vehicle is parked, the forward speed holding valve is controlled to assume the first valve position to engage the reverse frictional element.

Abstract: Transmission unit consisting of a continuously variable transmission (1); a hydraulic cylinder/piston unit (3) to set the transmission ratio of the continuously variable transmission (2); a pressure compensation chamber (4) working in conjunction with the cylinder/piston unit (3); and a passage organ (5) having at least one passage way (6) connecting the pressure compensation chamber (4) with the piston chamber (7) of said cylinder/piston unit (3), characterized in that the passage way (6) stretches at least partially along the outer surface of the passage organ (5).

Abstract: Pulley, in particular suitable for application in a continuously variable transmission, in which an endless belt can be fitted between the discs of the pulleys, the path of which endless belt can be influenced by a cylinder/piston device. The cylinder/piston device is provided with at least one pressure chamber provided with walls, one of the walls being provided with a resilient hinge, as a result of which elastic expansion of the wall around the hinge is achieved at relatively high pressures in the pressure chamber. Therefore, the shaft, along which at least one of the discs is axially displaceable, is not clamped and deformed to a lesser extent under heavy load, so that the action of the transmission is not impeded.

Abstract: A control system for a belt-type continuously variable transmission of a motor vehicle, having a primary and a secondary control valve for varying the transmission ratio. The primary control valve receives an electric signal from a control unit to vary a primary hydraulic pressure. The primary control valve produces a primary pressure which causes the transmission to take an intermediate transmission ratio when the electric signal is not transmitted due to a failure such as breakage of a cable. Thus, dangerous situations of the vehicle are prevented, and the vehicle can reliably start in a relatively low speed range of the transmission.

Abstract: Transmission unit for motor vehicles, consisting of a continuously variable transmission (2); at least one hydraulic cylinder/piston unit (13) with a pressure cheer (15) co-operating with the continuously variable transmission (2); a pressure compensation chamber (22) co-operating with the above-mentioned pressure cheer (15); and a passage connection (26) connecting the pressure compensation chamber (22) with the pressure chamber (15) , wherein a pressure-sensitive passage control member (28) is provided in the above-mentioned passage connection (26).

Abstract: A drive system for a conveyor belt drive assembly including a motor rotatably connected to the input shaft of a fluid coupling with the output shaft of the fluid coupling being rotatably connectable to the drive assembly. A motor speed controller controls the speed of the motor, so as to cause the drive shaft to maintain a desired torque.

Abstract: A clutch cooling system for cooling a clutch used in combination with a continuously variable transmission including a pressure controlled spool valve having a housing defining a chamber, a spool movably mounted by a spring within the chamber, and a notch defined by the housing such that as the leading edge of the spool aligns with the notch a variable orifice is formed; a pressure controller means for adjusting the pressure applied to the remote end of the spool such that as the pressure applied to the remote end is reduced the spring decompresses causing the spool to traverse the housing and further causing the leading edge of the spool to pass along the notch thereby increasing the size of the variable orifice; a slot located within the spool that allows for minimum cooling flow when the spool valve variable orifice is closed; a cooling fluid feed line and a clutch cooling line extending from the chamber such that cooling fluid can flow from the cooling fluid feed line, into the chamber, through the orific

Abstract: The invention relates to a rotary pump for use in particular in a continuously variable transmission. The rotary pump comprises a drive shaft with a rotor, in radial grooves of which movable displacement elements are disposed and slide along the radial inner side of a surrounding cam ring, forming variable pump chambers. The rotor is bounded at both long sides by end faces, an end plate being provided with some play between at least one end face and the rotor. One or more seals are provided between the end face and the end plate, to seal the supply and/or discharge apertures of the pump in order to prevent leakages between the end plate and the end face.

Abstract: A cone pulley transmission is disclosed which includes an infinitely actuatable and adjustable transmission wherein an axially displaceable cone pulley disc is adjustable by application of hydraulic tensioning so as to generate the pressure forces acting on a transmission belt rotating between the cone pulley discs, with the tensioning being controlled by a pressure medium through a sliding control valve. The tensioning is provided by different sized pressure chargeable surfaces and is throttled to different degrees with respect to the associated outlet of the sliding control valve. In this connection, it is provided that at least one outlet can be changed as a function of certain parameters.

Abstract: An infinitely variable cone disc transmission is disclosed in which the contact pressure forces are generated fully hydraulically and in which the contact pressure level is set either solely by way of a torque sensor that is disposed on the drive shaft and constitutes a pressure medium throttle that is adjustable as a function of the load, or in which a pressurizing valve preceding this torque sensor and controlled as a function of the transmission ratio is employed to additionally effect throttling as a function of the transmission ratio.

Abstract: An infinitely variable cone disc transmission is disclosed in which the contact pressure forces are generated fully hydraulically and in which the contact pressure level is set either by way of a torque sensor that is disposed on the driven shaft and constitutes a pressure medium throttle that is adjustable as a function of the load and the transmission ratio, or by way of a pressurizing valve that is connected in series with this torque sensor and controlled as a function of the load.

Abstract: A high pressure circuit is connected between a secondary pressure control valve and a lockup clutch control valve for actuating a lockup clutch of a torque converter. A low pressure circuit is connected between the lockup clutch control valve and a continuously variable transmission. A high relief valve is provided in the high pressure circuit for controlling the lockup clutch with high pressure. A low relief valve is provided in the low pressure circuit for lubricating a transmission belt so as to improve cooling efficiency.

Abstract: A system and several strategies for controlling a continuously variable transmission with an improved secondary servo arrangement in order to efficiently provide sufficient clamping forces under high torque conditions. The valving means allowing for the relative movement of the second variable pulley's movable sheave includes a valving arrangement operative to regulate the secondary apply pressure at or below the hydraulic source pressure and distinct from the primary line pressure. Control signals are developed to prevent belt slip and to efficiently launch a vehicle, maintain the necessary primary to secondary clamping force ratio in overdrive conditions, and avoid overpressurization of the secondary servo for many vehicle operating conditions.

Abstract: A method for regulating an automatic transmission unit having a plurality of coupling devices includes supplying a hydraulic medium to a control element; and supplying at least a portion of the hydraulic medium to a hydraulic regulating valve. The control element determines the portion of the hydraulic medium supplied to the hydraulic regulating valve and supplies that portion to the hydraulic regulating valve. The hydraulic regulating valve regulates an operational function of one of the coupling devices. When the central element fails, a safety device regulates the operational function of one of the coupling devices as a function of the revolution speed of a shaft of an engine.

Abstract: A continuously variable belt-drive transmission has a primary pulley operatively connected to an engine and a secondary pulley operatively connected to wheels of a motor vehicle, a primary cylinder and a secondary cylinder, and a hydraulic circuit having an oil pump. Primary pressure for the primary cylinder is generated by reducing secondary pressure. Steady flow rate in the primary system in a steady state is calculated, and transient flow rate in the primary system in a transient state is calculated. A primary pressure changing rate is determined to the value that the sum of secondary flow rate, the steady flow rate, and the transient flow rate becomes smaller than a discharge flow rate of the pump. In response to the primary pressure changing rate, a primary pressure control valve is operated so as to maintain balance of flow rate between the primary system and the secondary system.

Abstract: The invention concerns a drive device (7) with variable transmission ratio for driving an auxiliary aggregate of a motor vehicle. A belt pulley (11) of the drive device (7) has a chamber (38) connected to a reservoir (30) of a hydraulic medium. The centrifugal action of the hydraulic medium contained in the chamber (38) is used to change the speed of the driven shaft (13). By applying a supporting pressure to the chamber (38), it is possible additionally to vary the output speed of the drive device (7).

Abstract: A continuously variable transmission includes an improved secondary servo arrangement in order to provide the necessary clamping forces for high torque conditions. The secondary servo includes a plurality of fluid chambers in order to allow an increase in the area for application of fluid pressure. Fluid conduits between the chambers permit communication of the fluid to the chambers to regulate the clamping force of the movable sheaves of the secondary variable pulleys.

Abstract: A ratio control for a continuously variable transmission is disclosed. In this control, a speed sensor detects a wheel speed of a driving road wheel drivingly coupled with the continuously variable transmission, and the sensor output, namely a speed indicative signal indicative of the wheel speed detected, is used in conjunction with an engine load indicative signal in deriving a target value in a predetermined reduction ratio dependent variable, such as a turbine speed. Then, an actuator effects a shift in reduction ratio in such a direction as to bring an actual value in the predetermined reduction ratio dependent variable into agreement with the target value. During braking condition, the speed indicative signal may drop to zero or a small value owing to a wheel slip, resulting in a change in target value which causes a shift toward the maximum reduction ratio.

Abstract: A control valve in an automatic transmission is operated by a solenoid-operated relief valve. A flow rate of the oil through the control valve is calculated. A correcting value is calculated from the calculated flow rate so as to control pressure override of the relief valve to a predetermined value. A solenoid current applied to a solenoid of the relief valve is corrected with the calculated correcting value.

Abstract: Device for the regulation of a continuously variable transmission in motor vehicles, characterized in that it mainly consists of means for the supply of a hydraulic medium under pressure; control means for the regulation of a pressure; and a controller (13) formed of on the one hand a main valve (14) for the supply and discharge of the hydraulic medium to the regulating cylinder (8) of the continuously variable transmission (1), and on the other hand a control valve (15), whereby the valve bodies (16, 17) of the main valve (14) and the control valve (15) cooperate by means of elastic means, whereby the valve body (16) of the main valve (14) is loaded by a pressure regulated by the control valve (15) and whereby the valve body (17) of the control valve (15) is loaded by a pressure set by means of the above-mentioned control valves.

Abstract: In a continuously variable belt transmission wherein each of primary and secondary pulley devices consists of a stationary pulley and a movable pulley, and wherein the movable pulley is furnished with a hydraulic servo system having a cylinder which is connected at one end with the movable pulley, and a plunger which slides liquid-tightly within the cylinder; a pulley assembly for a continuously variable belt transmission (1) comprising the fact that the end (19b) of the cylinder (19) to be connected with the movable pulley (10b) of the secondary pulley device is formed with a clinch portion (19f) whose inside diameter is made larger than the outside diameter of the sliding part (16b, 18) of the plunger (16). In connecting the cylinder (19) to the movable pulley (10b) while covering the plunger (16) which is attached to the secondary shaft (5) of the transmission (1), the oil seal ring (18) of the plunger (16) is not nibbled.