Abstract: A method and apparatus for controlling the transmission ratio of a two-pulley type of infinitely variable V-belt transmission wherein the diameter of the driving pulley is adjusted in partial response to the fluid pressure in a hydraulic cylinder which controls the diameter of the driven pulley.

Abstract: In apparatus for controlling the transmission ratio of an infinitely variable V-belt transmission having variable pitch input and output pulleys operable by hydraulic cylinders, each pulley being formed of a pair of conical discs, at least one of which is axially movable relative to the other disc of that pair and the input pulley being driven by a power source: a hydraulic control valve for operating the cylinders, the valve having an internal axially movable spool; a device responsive to the speed of the input pulley for urging the spool in one direction; a compression spring urging the spool in an opposite direction, the spring being loaded through an intermediate connecting assembly by an external loading device; and a regulating device connected to the intermediate connecting assembly, the regulating device being responsive to an operating variable of the transmission.

Abstract: A composite driving belt in the form of an endless flexible carrier on which is mounted a plurality of plate-like elements disposed transverse to the carrier. The carrier is formed by a plurality of endless metal bands arranged in overlying concentric relationship, at least one side of at least one of the bands having surface roughness produced, for example, by two series of fine grooves which cross each other.

Abstract: Apparatus for controlling a clutch operable by fluid pressure in an operation space includes a fluid supply conduit, a rotatable control valve with a valve member displaceable by centrifugal force against the force of a biasing spring for connecting the fluid supply conduit to the operation space, and a fluid connection between the operation space and the valve member for supplying fluid pressure from the operation space to the valve member in a direction against the centrifugal force.

Abstract: A driving belt of substantially trapezium-shaped cross section for use with V-shaped pulleys, of the kind including an endless carrier and a plurality of plate-like elements disposed transverse to and slidably mounted on the carrier, each of said elements having an inner tapered end for engaging a V-shaped pulley groove, an outer end and opposite faces which abut the faces of the two adjacent elements, one of the faces at the inner end portion of each element being bevelled in a direction away from the adjacent element for enabling each element to tilt about a tilting line toward and away from said adjacent element whereby said belt can bend during use, one face of the outer end portion of each element having at least one projection which is releasably engaged in a corresponding recess in the face of the abutting element when the respective belt portion is straight, the improvement wherein said projections and recesses lie at a distance from the tilting line such that during bending of the belt and consequent

Abstract: In a driving belt for use with V-shaped pulleys, including an endless flexible carrier and a plurality of transverse elements abutting against each other in face-to-face contact and assembled on the carrier, said transverse elements being provided with coupling means comprising at least one projection at one face and at least one substantially corresponding coupling recess at the other face, the improvement wherein the thickness of the transverse elements at the location of the coupling means is smaller than the distance between the abutting faces of successive transverse elements.

Abstract: A transmission includes a hydrodynamic transmission, such as a torque convertor or a fluid coupling, connectable to a drive source and driving an infinitely variable V-belt transmission having primary and secondary pulleys each constructed of two conical pulley discs. The drive ratio of the V-belt transmission is controlled by a pressure cylinder which adjusts the axial position of one of the pulley discs, and the hydrodynamic transmission is lockable in a direct drive mode in response to the pressure in the pressure cylinder.

Abstract: A method of manufacturing an endless metallic belt of high strength for use as a drive belt or a part of a drive belt. A stress gradient is introduced in the belt in the radial direction thereof by bending the belt at such a radius as to produce plastic deformation of the metal. The belt is first subjected to tensile stress, which stress is maintained during the bending process.

Abstract: The invention concerns the control of an infinitely variable transmission, provided with an endless transmission member running over a primary and a secondary V-shaped pulley, one conical disc of each pulley being affixed to a shaft, respectively the primary and the secondary shaft, and the other conical disc being controlled in axial direction by a hydraulic cylinder-piston unit, respectively the primary and the secondary cylinder-piston unit, the tension in the endless transmission member being controlled by means of a first control valve and that the transmission ratio is controlled by regulating fluid supply and discharge from and to the other cylinder by means of a second control valve.

Abstract: The invention concerns a stepless variable belt transmission with pulleys which comprise two axially movable conical halves. The displacement of the pulley halves is effected by hydraulic piston-cylinder units rotating along with the pulleys. At least one hydraulic piston-cylinder unit is provided with a compensation chamber wherein a pressure is built up as a function of the speed. According to the invention the compensation chamber communicates with a closable opening with the cylinder chamber by means of which the pulley halves are relatively moved.

Abstract: Method and apparatus for driving an apparatus by means of a drive motor and an infinitely variable transmission comprising an endless transmission member running on at least two V-shaped pulleys having conical sheaves spaced apart a distance controlled hydraulically by means of a pump, which provides the necessary fluid pressure for control of the transmission ratio. According to the invention means are provided for ensuring that the transmission member is tensioned before, and so long as, the transmission is mechanically loaded, using one and the same drive motor. This is achieved by driving the pump by the drive motor and providing a clutch between the drive motor and the transmission, which is hydraulically operated by means of fluid provided by the pump, so that the clutch does not connect the drive and the transmission unless there is sufficient fluid pressure for the transmission to function.

Abstract: The fluid conduit of an hydraulic stepless variable transmission has a radial extension at its distal end terminating in a stationary chamber through which fluid is supplied to and discharged from a rotary piston-and-cylinder unit controlling the transmission.The radial extension rotates within the chamber along with the piston-and-cylinder unit, and thereby acts to compensate for pressure build-up within the cylinder chamber resulting from the effect of centrifugal forces.