Abstract: A shifting device (1) for pinion gear change transmissions which actuates the positive fit couplings by selector forks (3, 21) that slide on a stationary longitudinal guide (2). Shifting forces are transmitted from the shifting finger (9) to the selector forks (3, 21) by profiled metal plates (4, 5, 6) suspended in the selector fork (3, 21), the other end of the plates is guided in a switching comb (7) and the automatic locking device for blocking non-shifted gates and gears and gear selection is actuated via the locking plates (11) and sliders (16). The configuration of the inventive shifting device (1) makes it possible to provide a reliable, simple, low-costing shifting device suitable for various types of shifting mechanism such as lever shifts, turning-shaft shifts, cable and hydrostatic shifting mechanisms and automation modules.

Abstract: For testing the operation of the braking system of vehicles, in particular heavy trucks having an automatic multi-ratio mechanical transmission, an estimate for the total weight of the vehicle is formed on the basis of the vehicle's own parameters and driving parameters. If account is taken for the braking force or the acceleration in this calculation, in case of considerable deviations of the calculated vehicle weight from a threshold value, it can be concluded that a defect exists in the braking system of the vehicle. In this case, an alarm signal is given to the driver of the vehicle and/or directly geared to the operation of the mechanical transmission.

Abstract: A synchronizing device (2) is proposed for torque-transmitting connection of two rotary parts of a shift transmission, in particular for connecting a transmission shaft (4) with gearwheel (6, 8) rotatably supported on the transmission shaft (4). A synchronizer sleeve (30) has an outer disc carrier (36) connected with a gearshift device (64) and an inner disc carrier (34). A set of discs (40) is provided between the disc carriers (34, 36). The adjacent discs of the set of discs (40) are alternatively connected either with the inner disc carrier (34) or with the outer disc carrier (36). When the speed of rotation of the outer disc carrier (36) differs from that of the inner disc carrier (34), the discs allow a synchronization moment. For that purpose the outer disc carrier (36) has a device (62) for form-fittingly connecting the outer disc carrier (36) with a device (60, 76) on the gearwheel (6, 8).

Abstract: A control system for the automatic shifting of variable change speed transmission by an electronic control unit through which drive ratio change is determined in accordance with vehicle speed, instantaneous load demand and acceleration calculated from the speed of the driven shaft of the transmission. Drive ratio change command programs based on the behavior of a very good driver manually controlling a comparable transmission, are stored in the control unit to assign varying numbers of the available gear ratios to different combinations of sensed conditions under which automatic drive ratio change is effected.

Abstract: A drive arrangement for a commercial motor vehicle has a variable-speed transmission in which a brake is provided. The brake is formed as a radial-piston pump in which the piston under the control of the control pressure can be selectively coupled with a lifting element driven by a small gear meshing with a large gear on a driven shaft of the transmission.

Abstract: A start and shift clutch arrangement for motor vehicles with a disk clutch which during the sliding or friction generating phase is supplied with lubricating and cooling oil, and which runs dry when fully engaged or disengaged. The disk clutch is flooded in the area of the outer disks, whereby the maximum filling is limited by a first standpipe, and rapid emptying takes place via a second standpipe in conjunction with a control valve. Particularly advantageous is a self-contained lubricating system, which fills the clutch space during the sliding phase via an oil reservoir and an accumulator by a timed solenoid valve, utilizing compressed air. The accumulator equipped with a piston effects thereby alternately its own filling, and that of the clutch space.

Abstract: Control system for a pressure medium operated clutch (1) and reduction gear unit (4) to qualitatively improve torque reversal gear shifts by measurement of rotational speeds of the gear unit input shaft (41) and the turbine shaft (320) of a torque converter (3) through sensors (51, 52) and determination of differential speed conditions by an electronic unit (5) to which the sensors are connected. Upon displacement of the gear shift lever from neutral to gear drive position, the electronic unit issues a corrective fuel controlling command through line (22) for a length of time sufficient to obtain equality between the turbine speed (Nt) and the gear input speed (Ni) plus a correction factor (AN). The corrective command is applied to a control lever (71) of the engine fuel injection pump (7) through an automatic operating arrangement (90) superimposed on the fuel control linkage (8) connected to the control lever.

Abstract: Pressure-medium actuated shifting arrangement for a gear transmission, primarily for a multispeed transmission, in which the speed selection lever performs a movement in accordance with a double H shifting configuration. Within the reach of the driver, in a shift console another transmission shaft is mounted, which is displaced by the speed selection lever for path selection and twisted for gear shifting. The transmission shaft has also cams and valves cooperating with a pressure-medium source over the selection cylinder and shift cylinder mounted to the gear box which actuate a gear-shift-lever shaft, whereby not only the desired shift couplings are put into effect, but also feedback information about the shifting situation in the transmission perceptible by the driver is conveyed.

Abstract: In a mechanical gear selector for a synchronized gear change, there is disposed an automatic force amplifier--primarily a hydrostatically operating automatic amplifier--that amplifies or amplifies the force introduced depending on the magnitude thereof, no separate energy such as a fluid pump being needed therefor, and the amplification also taking place only when needed, primarily for the synchronization of gears. Between a force input shaft and a casing disposed concentrically thereto, which casing also transmits the amplified force, there is situated in connection with an annular and a pressure space the force amplifier proper and a spring element for the defined amplification threshold. On the design depends from what input force amplification starts. From a defined amplified pressure, the amplifying action is terminated by a pressure-reducing valve so that the transmission of force is continued practically with this pressure that has been reached or a pressure therebelow.

Abstract: A hydraulic retarder, especially for an automotive vehicle, comprising a control valve which regulates the pressure of the hydraulic fluid supplied to the decelerator which can be connected to a heat exchanger for dissipating the thermal energy generated by the retardation of the vehicle. According to the invention a regulating valve is additionally provided for controlling the maximum pressure in dependence upon temperature and in response to a temperature sensor. The device thus limits the maximum retarder effect in accordance with the temperature of the hydraulic medium and hence the utility of the heat exchanger to dissipating the braking energy.

Abstract: A gear-change mechanism for a conventional two-range speed-selection transmission comprises a gear-shift lever which is coupled to a shaft in a housing, this shaft carrying a pair of strikers which engage elements connected to the shifting rod. According to the invention, the striker forms a packet with a plurality of check plates disposed between and in front of and behind the striker plates and held on the shaft for axial displacement therewith. The check plates are guided in the housing so that they cannot rotate with the shaft.

Abstract: A hydraulic torque converter with a toroidal space bounded by a pump member, a turbine member and a free-wheeling stator has an inlet channel for fresh transmission fluid (oil) which opens into the pump torus at a location spaced from the pump member, preferably via the stator, whereby the relatively cool volume of newly admitted fluid mingles with the fluid already present instead of being immediately centrifugated toward the peripheries of the pump and turbine members from which it would quickly return to the sump. The inlet channel may include one or more radial passages in a spacer ring separating the stationary races of the journal bearings by which the pump member and the stator are supported on a trunnion rigid with the converter housing.

Abstract: A disk clutch inserted between a torque converter and a synchromesh gear train of an automotive transmission comprises a driving friction-plate carrier coupled with the turbine of the converter and a driven friction-plate carrier coupled with an input shaft of the gear train, the driving carrier forming two fluidically separated concentric cylinder spaces between itself and an operating piston embraced thereby. The inner cylinder is of smaller effective area and is pressurized in normal operation by hydraulic fluid (oil) but can be temporarily depressurized, during gear shifting, by a valve controlled by the shifting mechanism; this space communicates via an internal flow channel of the driving carrier with a radial bore in that carrier occupied by a centrifugally and/or resiliently loaded body of a quick-venting valve normally blocking an exit port leading from the outer cylinder space to the interior of a surrounding housing.

Abstract: A transmission shiftable to change transmission ratios by the operation of a member whose effectiveness depends upon a pressure fluid, e.g. through a valve communicating the fluid to actuators of the gear-change system, has a clutch connecting the output shaft of a prime mover as an internal-combustion engine with the input shaft of the transmission. According to the invention, the clutch-operating cylinder is connected by an entraining device with a valve controlling the pressure fluid. A lost motion may be provided between the operating member of the cylinder and the valve seats to ensure full opening of the clutch before operation of the transmission is enabled.