Abstract: A vehicle, in particular an agricultural one, for instance a combine harvester, has two axles (1, 2) drivable from two hydraulic motors (3, 4) switched in parallel, of which the one, non-steerable axle (1) is constantly drivable and the drive of the second steerable axle (2) may be connected or disconnected by means of clutch (11). In order to achieve a compact, stable and vibration-free auxiliary drive of the second steerable axle (2), the clutch (11), a planetary transmission (12) and a bevel drive pinion of an angle transmission (13) are arranged coaxially one behind the other between the associated hydraulic motor (4) and the axle (2). Due to this arrangement the hydraulic motor (4) of the second steerable axle (2) may be approximately half the size of the hydraulic motor (3) of the constantly driven axle (1). The clutch (11) and the planetary transmission (12) are combined to form a compact constructional unit (26) which is flange-connected to the axle housing ( 27) of the second, steerable axle (2).

Abstract: The invention provides a hydrostatic drive for vehicles, especially for the drive wheels of automotive heavy processing machines that have a drive for main drive wheels via a multispeed gear transmission and a drive for auxiliary drive wheels, wherein the drives for both the auxiliary drive wheels and the main drive wheels are hydrostatic. These hydrostatic drives each comprise an adjustable pump and an adjustable motor. A multispeed gear transmission is provided between the main drive motor and the main drive wheels and a clutch is provided between the adjustable motor and the auxiliary drive wheels. To obtain a higher travel speed, it is possible to disconnect the auxiliary drive and to switch, via a changeover valve, the delivery of the adjustable pump from the auxiliary drive to the main drive. Thereby is obtained the advantage that through the same control of both main and auxiliary drive wheels there is ensured a functional interplay of the drives.

Abstract: A hydrostatic-mechanical multiple-wheel drive for heavy vehicles with a multi-gear transmission for driving main driving wheels and hydrostatically operated additional driving wheels to be connected, as required, by themselves or when in one of the lower gears, including a variable displacement pump, driven directly proportionally to the speed of the main drive motor, for acting upon the additional driving wheels and an auxiliary pump acting as a filling and control pump, wherein, in order to control the speed with which the additional driving wheels are driven to that of the vehicle wheels, in particular to achieve synchronous running of these wheels, provision is made for orifices and/or throttles in the oil circuit of the auxiliary pump for varying the control pressure for the adjusting cylinder of the variable displacement pump so as to adjust these against the restoring force of the pump and of springs in the adjusting cylinder to the control pressure corresponding to the desired speed.