Abstract: A method for protecting a variator in a continuously variable belt-type transmission of a motor vehicle, simultaneously with a calculation based on an engine signal containing the magnitude of the engine torque and subsequent conversion of a contact-pressure theoretical value, providing the added safety on the variator, that the contact pressure on the variator is measured by a pressure sensor and the maximum transmissible transmission input torque is calculated with reference to this value. The maximum transmissible transmission input torque is then compared with the engine torque to the transmission and in case the maximum transmissible transmission input torque is less than the engine torque, an engine interruption is effected.

Abstract: Within the scope of the method for compensating angular misalignments for the variator of a continuously variable belt-drive transmission having cone pulleys disposed in pairs and one pushing linked band as torque transmitting belt-drive element, the fixed cone pulley of a variator side is designed with a curved outline, a pushing link displacement path being calculated with reference to a crowned pushing link flank outline and then the pushing link displacement path to the other side of the variator is calculated so that the displacement path is free of angular misalignment.

Abstract: A method is described for control of a CVT automatic transmission (1) in which a sensed main pressure (p_hd_act) and a sensed contact pressure (p_s2_act) of a secondary pulley (7) are entered as signals in an electronic transmission control (8). For diagnosis of an error in the sensing of the main pressure (p_hd_act) and/or of the contact pressure (p_s2_act) of the secondary pulley (7) their actual values or comparison variable (|p_hd_act-p_hd_nom|, |p_s2_act-p_s2_nom|) formed therefrom are compared with applicable threshold values (p_hd_min, pd_phd_regdiff, p_s2_min, pd_ps2_regdiff) associated with a range of plausible pressure values.

Abstract: The invention is based on a radial piston pump (1) with a pump body (2), in which pump body (2) are placed pistons (4), and cylinders (5) arrayed radial to a cam (14) and the pistons (4) upon an inward thrust suck in fluid by means of suction side intakes (17) and upon an outward thrust, the pistons (4) impel fluid through pressure openings (7) in the outer end walls (6) of the cylinder (5) into a plenum (10). It is proposed, that in the base of the cylinders (4) respectively a connection boring (32) is made to the cam (14), which connection boring (32) is controlled by a relief valve (18). Upon the exceeding of its opening pressure the relief valve (18) opens and pressure peaks in the cylinder (5) can be diminished by means of said connection boring. At the same time, a pressure buffer between the base of the piston (4) and the bearing shell (16) is formed.

Abstract: The automatic transmission for a motor vehicle having one starting element, one input shaft, one output shaft and gear sets for determining the reduction ratio and having one planetary reversing gear for reversal of direction of rotation of the input shaft. In the planetary reversing gear is situated one ring gear consisting of one ring (1) with inner teeth and with a smooth outer wall and of one disc carrier (2) segmentally welded on the ring.

Abstract: The invention is based on a radial piston pump (1) with a pump body (2), in which pump body (2) are placed pistons (4), and cylinders (5) arrayed radial to a cam (14) and the pistons (4) upon an inward thrust suck in fluid by means of suction side intakes (17) and upon an outward thrust, the pistons (4) impel fluid through pressure openings (7) in the outer end walls (6) of the cylinder (5) into a plenum (10) whereby the check valves (22) are formed from an annular coil spring valve (9) which cover the pressure ports (7) and the thereto connected stress relieving corrugations (8), and upon the exceeding of a specified threshold transport pressure, the respective pressure opening (7) opens to the plenum (10). The proposal is made, that a stress relieving zone (27) of a piston-cylinder unit (4, 5) be connected to the pressure zone (5, 7, 26) of a neighboring piston-cylinder unit (4, 5).

Abstract: An automatic transmission having at the input a starting element (4), a reversing set (46), a first electronic control unit (65) and a cone pulley (29) fixedly supported on one primary shaft (18) and axially thereto a hydraulically adjustable cone pulley (30), both pulleys forming a primary variator part (19). In addition there is a cone pulley (31) fixedly supported on a secondary shaft (21) and axially thereto a hydraulically adjustable cone pulley (32) together forming a secondary variator part (20) wherein a belt-type organ (37) between the cone pulleys (29, 30, 31,32) drivingly connects the primary variator part (19) with the secondary variator part (20).

Abstract: In an assembly of an electronic element (4) and a hydraulic element (3) of a control device (2) for the automatic transmission of a motor vehicle with a partially oil filled transmission housing wherein the control device (2) is arranged in the transmission housing wherein said control device (2) is arranged in the transmission housing and is at least partially surrounded by oil, the hydraulic element (3) has a valve housing (5) on which hydraulic valves (6), speed sensors (7, 8, 9) and pressure sensors (10, 11) are provided and is designed with a first housing part (5A) and a second housing part (5B). The first housing part (5A) has an at least approximately cuboid shape and is substantially arranged below a set of conical disks (1A) of a variator (1).

Abstract: Engine torque control system based on the dynamic behavior of a driven automatic transmission consists in that the engine dynamics is limited as function of a sporting mode.

Abstract: Within the scope of the method for ratio control of a continuously variable automatic transmission of a motor vehicle by means of a control loop structure which contains a non-linear compensation member for the variator and controllers for the pressures of both hydraulic routes of the variator pulleys and the variator routes, the control loop structure contains an interference variable observer which generates an interference force FL that reproduces the pattern precision wherein the interference force together with the set value for the adjustment gradient which is limited as result of external standards, forms the compensation member.

Abstract: The radial piston pump has a number of cylinder bores in a pump housing to accommodate pistons which slide into them; the cylinder bores are plugged by pressed-in stoppers (3) in which pressure channels are incorporated, all stoppers being sealed by a flat spring (6) which serves as return valve. To enlarge the outflow cross section through the pressure channels, each stopper 3 has at least one side discharge channel (8, 9).

Abstract: The device to control a continuously variable automatic transmission (CVT) having a first bevel pulley pair, upon an input shift and a second bevel pulley pair upon an output shaft and a belt drive organ extending between the bevel pulley pairs, wherein the movable parts of the bevel pulley pairs are displaced in an axial direction by electromagnetic actuators and hydraulic pressure regulating valves, as well as adjusting cylinders, comprises a closed hydraulic circuit regulated at a constant pressure so that leakage flows of the adjusting cylinders for the bevel pulley pairs and leakage flows of the pressure-regulating valves are delivered directly to a hydraulic constant pressure circuit such as the circuit provided for supplying the torque converter and to the secondary circuit serving for lubrication.

Abstract: A continuously variable transmission for motor vehicles having a first cone pulley pair and a second cone pulley pair over which runs a belt drive organ. Between the primary pulley (11) and a cover (2) in the transmission housing (1), there is provided for the fluid required to adjust the primary pulley (11), a primary pressure line extending substantially radially toward the center of the rotating primary shaft (12) and from which branches off a lubrication pressure line (8) for the rotating primary shaft (12). The fluid is conveyed between an inner cover (6) and the cover (2).

Abstract: A hydraulic system for pressure control of a variator (7) of an automatic transmission having an electronic transmission control is connected with a lubricant circuit (10) in which at least one lubrication valve (14) and one radiator (13) are situated. Oil is fed to the hydraulic system with the lubricant circuit (10), from an oil source (4). At the same time, a hydraulic emergency device is provided which has at least one emergency valve (29) to provide a constant pressure ratio between a primary pulley set (19) and a secondary pulley set (20) of the variator (7). In addition, the system has for reducing the thermal load in the emergency operation at least one device (35, 37, 43, 45, 46, 51) by means of which in emergency operation the oil flow through the radiator (13) is increased and the pressure on one output side of the radiator (13) is reduced.

Abstract: The invention relates to a method for manual control of the ratio of a continuously variable transmission (CVT) for a vehicle. The CVT has one control device, one shifting or selector device, one starting element and one variator for ratio adjustment and is driven by an internal combustion engine. The control device processes input signals derived from a driver-vehicle system within the scope of an operating strategy under the control of the reduction ratio, the rotational speed of the prime mover, or an input rotational speed of the variator. The operation strategy automatically selects in an automatic operating mode the transmission ratio. In a manual operating mode, the driver can engage directly in the selection of the transmission ratio via the shift or selector device. It is proposed that in the operating mode there is manually preset a signal proportional to the vehicle speed which is further processed as a theoretical guidance for the operating point of the engine-transmission unit.

Abstract: A method for ratio control for a continuously variable belt drive transmission with electrohydraulic control by means of a control loop with a linear PID controller with the theoretical ratio of the variator iv_theor.

Abstract: A system for control of a CVT driven by a drive unit has an electromagnetically controlled pressure-control valve which actuates both a main pressure valve and a secondary valve for the secondary pulley wherein geometry and spring tension of a main pressure valve and the secondary valve provide different characteristic lines.

Abstract: The invention concerns an automatic controlled transmission having a hydrodynamic converter (1) and a lock-up clutch (10) between an input shaft (7) and an output shaft (8) of the converter (1) wherein the lock-up clutch (10) is actuated by the differential pressure between an intake (14) and return flow (15) of the converter (1) and traversed by a coolant current. It is proposed that the coolant flow be controlled depending on the temperature of the oil. Thereby the transmitting capacity of the lock-up clutch (10) when engaged state is not impaired even when for cooling a larger coolant flow rate through the converter (1) is provided.

Abstract: The device for the control of an automatic transmission, especially a CVT, which is connected with an oscillatingly suspended drive mechanism, preferably an internal combustion engine for a motor vehicle with front-transverse drive mechanism, wherein the transmission has an electronic control, is provided with a sensor in the form of a piezoceramic transmitter on a torque support for the drive mechanism for producing high dynamic, to provide engine-torque equivalent signals which are fed to the electronic transmission control.

Abstract: The method for monitoring a continuously variable transmission (CVT) with a variator for adjustment of the speed ratio, which has its primary and secondary adjustment devices respectively controlled by a pressure-regulating valve, consists of a travel monitoring and/or pressure monitoring of the pressure-regulating valves wherein in case of detection of an incorrect operation the power-flow transmitting clutch is opened.