Zahnradfabrik Friedrichshafen, Ag.

Other

Michael Meyerle

Friedrich J Ehrlinger

Anton Ott

Egon Mann

August Winter

Gisbert Lechner

Otto Anton

Ehrlinger Friedrich

A hydrostatic/mechanical branch power split transmission for power vehicles is disclosed. The transmission includes an infinitely variable hydrostatic converter having a first hydrostatic unit of adjustable volume and a second hydrostatic unit. The transmission also includes a power distribution system whereby the driving power is split into a hydraulic and a mechanical branch and is summed again before the transmission output. The transmission permits various driving strategies or driving programs which can be conveniently adjusted and accessed. There is also a hydrostatic connection which can be switched at several gear racial points. The breaking capacity of the engine and the maximum breaking effect through continuous hydrostatic converter can be utilized and easily controlled. A further variant also enables breaking energy to be recuperated with the hydrostatic converter. The continuous converter can be precisely adjusted to optimize gear shift range selection.

Continuous hydrostatic-mechanical branch power split transmission

A hydrostatic/mechanical branch power split transmission for power vehicles is disclosed. The transmission includes an infinitely variable hydrostatic converter having a first hydrostatic unit of adjustable volume and a second hydrostatic unit. The transmission also includes a power distribution system whereby the driving power is split into a hydraulic and a mechanical branch and is summed again before the transmission output. The transmission permits various driving strategies or driving programs which can be conveniently adjusted and accessed. There is also a hydrostatic connection which can be switched at several gear ratio points. The braking capacity of the engine and maximum braking effect through the continuous hydrostatic converter can be utilized and easily controlled. A further variant also enables braking energy to be recuperated with the hydrostatic converter. The continuous converter can be precisely adjusted to optimize gear shift range selection.

Stepless hydromechanical mechanism with multiple power-transmission paths, more particularly for motor vehicles, having at least two switching ranges in which the stepless control of the mechanism is effected by a hydrostatic transmission, in which the specific requirements on the hydrostatic unit are reduced to a minimum. The hydrostatic power content is reduced. The parameters determining noise, efficiency and service life, i.e., hydrostatic pressure, hydrostatic speed, as well as the values of these components and their arrangement are brought into acceptable and technically feasible bounds. To this end, two summation planetary gearing mechanisms are provided in which the input shaft of the transmission is drivingly connected to a first hydrostatic unit and to a first inlet shaft of the first summation planetary gearing mechanisms, and a second hydrostatic unit is connected to a second inlet shaft of the first summation planetary gearing mechanism and to a first inlet shaft of the second summation planetary gearing mechanism.

Stepless hydromechanical mechanism with multiple power-transmission

A hydromechanically infinitely variable transmission with power splitting for motor vehicles with at least five gearshift ranges. The transmission can be infinitely varied by means of a hydrostatic transmission. A hydrostat transmission, a multi-shaft summation planetary transmission and at least two downstream planetary transmission units constitute basic components which can be mutually coupled in transmission combinations of various configurations. The power summarized in the summarization planetary transmission is transmitted alternately through an intermediate shaft or coupling shaft and clutches to a planetary transmission unit. In at least one gearshift range, a shaft of the summarization planetary transmission is connected directly via a clutch to the output shaft. Depending on the embodiment, one to three reverse gear ranges can be incorporated in the transmission.

Hydromechanically infinitely variable transmission, with power

Branched infinitely-variable hydromechanical transmission for motor

A clutch mechanism, particularly for automatically operated automotive transmissions, for engaging shift ranges of continuously variable transmissions or step-by-step variable transmissions, and having at least two independently axially movable clutch rings with clutch profiles which cooperate with respective corresponding mating clutch rings clutch profiles, a clutch carrier mounted on a transmission element for rotation therewith in a fixed axial position, and having fluid actuated pressure pistons for shifting the movable clutch rings toward the mating rings. The clutch system can be disengaged under load and requires a small construction space. It can be produced at low cost and is almost free from drag losses. Clutch times and clutch travels are short. The shift pressures are very low. In addition, several clutches can be combined into a compact and relatively small clutch assembly.

Clutch, particularly for automatic transmission for automotive vehicles

An infinitely variable driving and steering gear for track-laying vehicles has a hydrostatic/mechanical overlaying steering gear. The mechanism includes a hydrostatic unit and a summation gear train for summing hydrostatic and mechanical input power. The summation gear train has one or more summed power outlet shafts. The drive mechanism also includes a first multiple shaft steering summation transmission that is operably coupled to the summed power outlet shafts and which has left and right steering output shafts. The drive mechanism also includes a second multiple shaft steering summation transmission having respective output shafts that are operably connected to first steering summation transmission. The shafts of the summation gear train of the driving transmission and the shafts of the first steering summation transmission are all coaxially arranged for rotation about a common axis.

Infinitely variable driving and steering transmission mechanism for

Continuous speed-change branched gear, in particular for motor vehicles

A hydromechanical transmission has an engine-driven power shaft connected to a variable-volume pump forming the input side of a hydrostatic unit whose output side comprises a constant-volume motor connected to this pump. A summing planetary-gear train has a first ring gear connected directly to the power shaft, a second ring gear connected to the hydraulic motor and a planet carrier with two interengaging sets of planet gears, one set meshing with the first ring gear and the other set meshing with the second ring gear as well as with a sun gear. An output shaft of the transmission can be connected via a high-range clutch to the sun gear of the summing train or via a low-range clutch to the planet carrier thereof to provide a speed ratio which is steplessly variable in two ranges.

Hydromechanical drive

In order to control an infinitely-variable transmission of a vehicle engine, a memory stores an optimum fuel consumption curve by which signal transmission is modified through the throttle valve control line or an adjustment regulating valve line for a servomotor connected between the accelerator pedal and the transmission whose ratio is controlled by the servomotor.

Motor vehicle control for an infinitely variable transmission

A drive system for a track-laying vehicle has a main drive shaft connectable to an engine and to primary inputs of right and left summing transmission having secondary inputs and having outputs connected to the secondary inputs of the summing transmissions so that when the compensating shaft is rotated in one direction the one input is rotated one way and the other the opposite way and vice versa. A planetary-gear transmission has a pair of separate inputs and an output connected to the compensating shaft. A variable speed hydrostatic transmission has its input connected to the main drive shaft and its output connected to one of the inputs of the planetary-gear transmission. A first clutch has one side connected to the output of the hydrostatic transmission and to one input of the planetary-gear transmission and another side connected to the compensating shaft. A second clutch has one side connected to the other input of the planetary-gear transmission and another side operatively connected to the main drive shaft. This first clutch is closed and the second clutch is open for low-range steering, and vice versa for high-range steering for a sharp turn.

Drive system for track-laying vehicle

This invention is for a hydrostatic-mechanical transmission system of the power-branching type having a 'neutral' operating mode. An assembly of a hydrostatic transmission including a variable displacement pump and a hydraulic motor is connected to the input shaft of a mechanical transmission. The mechanical transmission has a speed-range selector defining a first low-speed range for the gearing and a second high-speed range for the gearing. Two planetary gear sets in succession are coupled to the transmission such that the transmission ratios of the hydrostatic transmission and the mechanical transmission establish a neutral mode in each speed range a zero output contribution by the mechanical transmission.

Hydromechanical transmission with power branching

A hydrostatic-mechanical gear unit wherein input power is divided into an hydraulic power branch and a mechanical power branch. The hydraulic branch includes two hydrostatic units in tandem. Through gearing the hydraulic branch is directed to a first internal gear for transmitting the rotational hydraulic power. The mechanical branch through gearing leads to a second internal gear for transmitting rotational mechanical power. The internal gears together with pinions form part of a planetary wheel set for integrating the mechanical power and the hydraulic power. An intermediate shaft connected to the pinion carrier conveys power to an output shaft through a coupling in a first forward driving stage and in the reverse driving stage, and a coaxial shaft connected with a sun wheel conveys power to the output shaft through a coupling in a second forward driving stage.

Hydrostatic-mechanical gear unit

A hydrostatic transmission coupled with a gear transmission for operating a motor vehicle driven by an internal combustion engine has its accelerator pedal connected to the throttle valve of the engine and to the servovalve of the stepless hydrostatic transmission via an engine characteristic storage which modulates the accelerator travel signal applied to the servovalve to optimize the fuel consumption. The servovalve also receives input from an electric signal comparator which compares the engine speed with an output signal from the output unit of the hydrostatic transmission or the output shaft of the gear transmission.

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Meckenbeuren, Germany

Michael Meyerle