Man Nutzfahrzeuge Gmbh

Maschinenfabrik Augsburg-nurnberg Aktiengesellschaft

M.a.n. Maschinenfabrik Augsburg-nurnberg A.g.

Man Nutzfahrzeuge Ag

Man Nutzfahreuge Gmbh

Faust Hagin

Hans J Drewitz

Stefan Martini

Hans-Jurgen Drewitz

Hans Hagen

Manfred Stiglmaier

Manfred Krenner

Gerd Ruhmann

Robert Zelinka

Helmut Flenker

Erich Knirsch

Paul Merker

Franz Seethaler

A stepless hydrostatic mechanical transmission between a prime mover and a power output train in which an epicyclic differential is incorporated in the transmission and includes at least four shafts, a large and a small sun wheel, two planet wheels in mesh with the sun wheels, a web supporting the planet wheels and an annulus. Two main shafts constituting input and output shafts are connected with respectively different shafts of the epicyclic differential. Two hydrostatic machines are connected to the epicyclic differential such that in at least one working range of the power transmission the hydrostatic machines are adapted to be connected to the epicyclic differential and operated as pumps and motors. The operation of at least one of the hydrostatic machines is changed over by a clutch, when the other hydrostatic machine is stationary and during transition from one working range to another, from connection with the output shaft to the small sun wheel and, during traction operation, from the motor function to the pump function. In the epicyclic differential, the large sun wheel is driven by the input shaft and is located between the small sun wheel and the prime mover.

Stepless hydrostatic-mechanical transmission

In the case of hydromechanical power splitting transmission for vehicles the aim of the invention is to make possible the use of the same type of hydrostatic machine is hitherto and of an identical or similar four-shaft planetary differential transmission while at the same time expanding the effective range of conversion to cover substantially at least twice the range. This is achieved in that the hydromechanical power splitting transmission is designed for an extremely wide overdrive operation with a speed of rotation ratio (noutput: ninput of the two main shafts) of up to a maximum of 2. This is achieved by the addition of simple gear trains and the additional provision of clutches. Control devices are provided to so act on these additional clutches so that on transition from the second to at least one further operational range leading to the overdrive range, disengagement of one clutch disconnects the first hydrostatic machine (which has heretofore been connected with the annulus of the planetary differential transmission) and by engaging a further clutch at sync speed it is connected with one of the two main shafts of the power splitting differential transmission.

Vehicle drive device with a hydrostatic-mechanical power splitting

In order to avoid the necessity of a conventional electric starter motor a hydrostatic starting system for the engine of a motor vehicle is proposed for the engine whose output shaft is connected with a hydromechanical power transmission, composed of a mechanical part and at least two hydrostatic machines. The starter system comprises its own hydraulic accumulator which as regards its filling capacity and power output is designed for starting the engine at least once and a controller which responds to certain halt and operational states of the vehicle. The charging of the hydraulic accumulator takes place during braking of the vehicle via the hydrostatic machines of the power transmission or, if there is insufficient brake power, of an auxiliary device.

Starter system for automatically turning off and restarting a motor

In a system for varying the output flow from a constant rate feed pump with low losses by chopping the said output flow into one flow fraction supplied to the load as a power flow and into another flow fraction returned as a pressureless flow, the loads are aperiodically supplied with proportionated amounts of fluid by chopping, the respective amounts of fluid and the chop frequency being inherently controlled in way dependent on the instantaneous requirement of the load in the system. The system for performing the method has a housing with a number of pressure spaces arranged to be acted upon by different flows and with one or more pressureless spaces, a piston with a piston rod arranged in a piston space, a compression spring preferably arranged in a hole in said piston rod and adapted to act against the sum of the hydraulic forces acting on the piston and spool. The method is applicable to complex hydraulic systems and more especially to hydrostatic drives.

Low-loss cyclically-operating pressure-responsive bypass valve for fixed

A device for automatically resetting the play between a brake lining and a rotating brake member which is to be braked. The device is able to take into account an increase in the play due to wear as well as a decrease in the play due to overadjustment due to internal elasticity and heating, during each braking operation by suitably dimensioned positive and negative resetting. The device employs a setting member which is rotatable in a housing and with which a coupling can be engaged to drive a setting shaft and thereby take up play during braking. As the braking force increases, the coupling is locked against rotation and as the setting shaft undergoes further displacement, the play is slightly increased.

Brake play resetting device

A hydromechanical power splitting transmission for use between the prime mover and the axle power train of a vehicle having a planetary differential drive with at least two series of planetary wheels, two sun wheels, a web and annulus, a drive input shaft and a drive output shaft, connected with different shafts of the planetary differential drive. There are furthermore at least first and second hydrostatic machines, which in at least one operational range are connected with one shaft of the planetary differential drive and at least the first of the hydrostatic machines is able to be switched over from its own shaft to another on changing the operational range by clutches, while the second hydrostatic machine is at least substantially stationary. In the operational state of the vehicle in which the ratio of n.sub.output to n.sub.input &gt;approximately 50%, the first hydrostatic machine is connected to the transmission output shaft via one of two speed change devices of different size, selectively operated by a two way clutch. The larger of the two change speed devices is used for forward travel at creep speed and predominantly for reverse of the vehicle and is switched over into this drive ratio when the transmission is stationary.

Hydromechanical power splitting transmission for vehicles

The hydromechanical transmission is all in all designed as a power splitting transmission having at least two hydraulic machines adapted to selectively act as pumps and motors, a control or connecting block, epicyclic gearing and various clutches, the hydraulic machines adapted to selectively act as pumps and motors forming a preassembled unit or subassembly with the control or connecting block. The subassembly, the epicyclic gearing, the clutches and any intermediate shaft required are arranged in a unitary manner in a common housing, in which the various elements are surrounded with a small clearance. the hydraulic machines adapted to selectively act as pumps and motors are arranged within the overall length of the epicyclic gearing and are axially parallel thereto.

Hydromechanical transmission for motor vehicles

The chassis of a motor vehicle is fitted with spaced bearer bars running parallel to the lateral longitudinal members of the chassis, with which the bars are connected at their ends by junction plates. Each bearer bar has a horizontally extending center part with downwardly extending arms at its ends. The center part bears on a wheel spring. There are further junction plates connecting the center part of the bar with the respective longitudinal beam.

Structural element for supporting the chassis or superstructure of a

A drive axle with a gear ring meshing with a drive pinion is designed with silent running properties, in that an intermediate member is secured to the differential carrier and is connected to the gear ring by an elastic coupling. Between the contacting faces of the gear ring and the intermediate member there are annular grooves and a cylindrical space is formed between an inner face of the gear ring and an outer cylindrical face of the intermediate member. The cylindrical space and the annular rings are filled with a viscous substance.

Differential whose a ring gear is mounted in sound damping manner on its

The invention is concerned with improvements in utility vehicles having hydraulically driven items of equipment and designed for frequently stopping and starting, such as a garbage collection vehicle, a forklift truck, an excavator or the like. In order to facilitate operation of the equipment the vehicle has its engine connected with a hydromechanical four-shaft power branching transmission as previously proposed for use in city omnibuses operating city services. The branching transmission is adapted for operation in at least two working ranges and has at least two hydroconverters. The one hydroconverter is connected with a power output shaft at least in the starting up state of the vehicle. A second hydroconverter is connected with a shaft different to the transmission input shaft and the transmission output shaft. The pumps of the hydraulic power circuitry for operation of the equipment of the vehicle are able to be connected via clutch with the shaft of a hydroconverter, more especially of the second hydroconverter. This avoids the necessity of having a special auxiliary output transmission driven by the engine.

Utility vehicle designed for frequent starting and stopping

A vehicle, more especially in the form of an articulated omnibus, has a hybrid drive system comprising an IC engine and an electric motor, whose power is transmitted not only to an axle driven by the IC engine but in addition to a further drive axle in order to extend the working life of the transmission axles.

Articulated vehicle selectively driven at two axles from two power

An energy storage device comprising a high pressure liquid accumulator, a low pressure liquid accumulator and at least one pump and motor unit, i.e. a device able to be used as a pump and a motor which is connected to a means, such as the drive train of a vehicle, supplying or absorbing energy as the case may demand and during charging of the high pressure liquid accumulator from the low pressure accumulator functions as a pump and on discharge thereof functions as a motor, at least that pressure line connecting the high pressure accumulator and the pump and motor unit having a shut off valve therein. A piston delimiting the storage space of the low pressure liquid accumulator is connected to a telescoping cylinder bearing against the end plate of the accumulator and the cylinder is connected via an operating pressure line with the high pressure accumulator for pressurization. On charging of the high pressure accumulator with an accompanying discharge of the low pressure accumulator it is thus possible to avoid a fall in the pressure in the latter to an overly low level; in fact the pressure fluctuates about an average value between a relatively high minimum value and a maximum value. The latter feature is due to the changing size of the active pressure faces as the telescoping pressure cylinder is extended one part after another.

Energy storage device

In a system with an energy storing and releasing device the latter comprises a high pressure accumulator and switching over device for the charging and discharging of the latter from and to a low pressure accumulator using a hydraulic transducer which is connected with a device able to provide and take up power. The switching over device consists of four 2/1 way shut off valves of which two respective ones are placed in parallel and connected with a respective accumulator. The 2/1 way shut off valves are so connected with the hydraulic transducer that by paired switching of a respective one of the two 2/1 way shut off valves associated with one accumulator either the one or the other accumulator may be connected with the power input of the hydraulic transducer and switching over may take place from the power output of the latter to the other accumulator. By the use of simple 2/1 shut off valves the switching over device is generally simplified to a substantial extent.

Device for storing and releasing energy

In a hydrostatic drive one hydrostatic machine (2 and 4) is adapted for absorbing the sustained braking power or energy. The transmission is furthermore provided with a cooler (9) whose two sides are respectively connected via a threshold pressure valve (7 and 8) with one of two branch ducts (3 and 5) which connect the said hydrostatic machine with a second such machine adapted to act as a drive. The pressure threshold valve is made up of a pressure limiting and check valve.

Hydrostatic drive

The invention relates to a fluid tight pipe connection having an intermediate ring between the two pipe ends. By making the two surfaces of the ring complementary to the pipe end faces the ring may be displaced in relation to one pipe end and may be moved pivotally in relation to the other pipe end to enable the connection to allow for angular misalignment and parallel offset of the pipe axes while still maintaining a sealing joint.

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Munich, Germany

Faust Hagin