Robert Boschgmbh

Stuttgart

Paul Bosch

Hans-Jurgen Fricke

Emil Knodel

Gerhard Nonnemacher

Wilhelm Dworak

Gerhard Nonnenmacher

Karl-Heinz Muller

Siegfried Mayer

Walter Robeller

Claus Jons

Wolfgang Talmon

Jan Vlemmings

Ivan Sauer

Martin Fader

Egon Tittmann

Jurgen Zorn

Eugen Hartmann

Gunter Ital

An internal-gear fluid-displacement machine, such as a fluid-displacing pump or a fluid-displaced motor includes an internal gear and a spur gear which meshes with the internal gear at a meshing region. A separating body fills a separating region between the gears which narrows toward the meshing region and separates the same from the remainder of the interspace between the gears. An actuating lever is mounted on the housing for pivoting and extends through the interspace, and a piston subjected to the pressure prevailing at the meshing region abuts against a free end of the actuating lever, pressing the same into abutment with that end of the separating body which faces into the remainder of the interspace. A strap connects the separating body to the actuating lever. The axial sides of the separating body have depressions therein which are bounded by narrow sealing projections which converge toward the meshing region.

Internal-gear fluid-displacement machine with movable separating body

An arrangement for pumping fluids includes at least one variable-output pump and a drive therefor. An auxiliary pump is also driven by the drive and discharges control fluid at a discharge rate which corresponds to the speed of rotation of the drive. A throttle valve is located in a discharge conduit of the auxiliary pump, and the pressure of the control fluid upstream of the throttle valve controls the displacement of a slide valve between two positions thereof in one of which the control slide controls the variable-output pump toward increasing the output thereof, while in the other of such positions the pump is controlled toward a reduced output thereof. In addition to the pressurized fluid, which acts on the control slide with a first force, a spring is provided which acts on the control slide with a second force opposing the first force. One of these forces is varied in response to variations in the output rate of the variable-output pump so that the ratio of the first force to the second force increases with the diminishing output rate of the variable-output pump. Advantageously, the position of an adjusting element of the variable-output pump is used as an indication of the output rate of the pump. The signal derived from the position of the adjusting element is used either for tensioning or relaxing the spring, or for increasing or decreasing the flow-through cross-sectional area of the throttle valve.

Control device for a pumping arrangement

A radial piston machine in which a rotor with radial bores is rotatable on a trunnion integral with the machine housing. Pistons, preferably in the form of hollows balls, are respectively located in the bores of the rotor and moved during rotation of the latter along suction and compression strokes by engagement with a displacement ring eccentrically arranged with respect to the rotor axis. Channels in part formed in the trunnion serve for feeding pressure fluid in and out of the machine.

Radial piston machine

A control arrangement for preventing overloading of a prime mover which drives a pump comprises a pair of hydraulically operating adjusting units operative for adjusting the volume of fluid discharged by the pump. The arrangement further comprises a negative-feedback stabilizing circuit connected to the adjusting units and to a multi-setting regulating valve. The stabilizing circuit is operative for causing the valve to regulate the operation of the pump by controlling the operation of the adjusting units in dependence upon the output pressure of the pump. In order to protect the prime mover when the loading thereof has reached a predetermined value, an overload signal is generated which actuates an over-ride device. The override device is operative in response to the overload signal to cause the valve to assume a setting such that the adjusting units decrease the quantity of fluid discharged by the pump so as to unload the prime mover.

Control arrangement for preventing system overload

An arrangement for pumping fluids includes at least one variable-output pump and a drive therefor. An auxiliary pump is also driven by the drive and discharges control fluid at a rate corresponding to the speed of rotation of the drive into a discharge conduit in which a variable flow-through cross-sectional area throttle valve is located. The pressure in the discharge conduit upstream of the throttle valve controls the displacement of a control slide between the two end positions thereof in one of which the control slide controls the variable-output pump so as to increase the output thereof, while in the other of such positions of the control slide the pump is controlled so as to reduce the output thereof. The throttle valve is responsive to the pressure in the discharge conduit, but can be arrested in any position thereof when the drive is overloaded so that the flow-through cross-sectional area thereof is fixed, which results in a decrease of output of the variable-output pump when the drive is overloaded. Advantageously, the throttle valve is arrested when the power input to the drive exceeds a predetermined value. The arresting of the throttle valve may be effected by using an actuating electromagnet which is energized in response to overloading conditions of the drive by a switch interposed in the electric circuit of the electromagnet and controlled by the drive.

Pumping arrangement control device

An external gear type hydraulic pump or motor wherein the trunnions of gears in the chamber of the housing are surrounded by annular bearing members. The peripheral surface of each bearing member defines with the adjacent internal surface of the housing an arcuate gap whose width increases in a direction toward the respective end face of the corresponding gear. To this end, portions of or the entire peripheral surfaces of bearing members and/or portions of or the entire internal surfaces of the housing have a conical or spherical shape. The gaps are located in the low-pressure zone and reduce the likelihood of wear upon those end faces of bearing members which are adjacent to the end faces of the gears because the bearing members can tilt in response to increasing load without localized rubbing against the gears. Additional gaps can be provided between the end faces of the gears and the adjacent end faces of the bearing members to further reduce the likelihood of uneven wear upon the bearing members.

External gear type fluid displacing machine with bearing gap

A hydraulic control device for protecting a drive from excess loading conditions includes at least one pump having adjustable members for controlling the quantity of fluid transported by the pump. A pressure-responsive control slide is mounted for movement relative to a housing and is moved towards respective positions, each of which corresponds to a normally loaded condition of the drive by a control pump which generates a pressure force which is indicative of the rpm of the drive at normally loaded conditions. The device further includes an arrangement for securing the control slide when the drive is subjected to loads in excess of the respective normally loaded conditions so that a valve member is permitted to move in response to excess loads relative to the control slide after the latter has been secured in said respective positions by the securing arrangement between switching positions in which the adjustable members are operative to adjust the quantity of fluid being transported by the pump.

Hydraulic control device

In a hydraulic axial piston machine, which may be a pump or hydraulic motor, whose cylinders are located on a larger circle than the cylinder ports and the stationary high pressure and low pressure ports of a stationary body, a tilting moment is exerted on the cylinder block which is compensated by radial pressure exerted on the cylinder block by positioning cylinder and piston members operated either directly by high pressure fluid from the high pressure conduit of the stationary body, or indirectly under the control of a valve operated by leakage fluid obtained from a recess in the control face of the stationary body.

Cylinder block positioning arrangement for a hydraulic axial piston

A gear pump having a drive gear provided with trunions mounted for rotation in the housing of the pump and a driven gear meshing with the drive gear and guided in the housing only on side faces and a portion of the inner peripheral surface of the housing and pressed by fluid pressure against the driven gear. A first sealing member at the outlet of the housing presses the driven gear against a sealing zone of the housing adjacent the inlet thereof and a second sealing member subjected to fluid pressure presses the driven gear against the drive gear. A low pressure zone is arranged at the inner peripheral surface of the housing between the two sealing members, whereas a high pressure zone is arranged between the second sealing member and the sealing zone.

Gear pump

Two adjustable-stroke pumps are driven off a common drive shaft and supply fluid to respective consumers via respective control valves settable by the user of the system. Each pump is provided with its own pressure regulator operative for regulating the output pressure of the respective pump by automatically adjusting the setting of the stroke-adjustment member of the pump. Transducers generate first signals indicative of the settings of the stroke adjustment members and second signals indicative of the settings of the control valves. A control arrangement maintains the settings of the volume-adjustment members in correspondence with the settings of the control valves by automatically altering the operation of the pressure regulators in response to discrepancies between the settings indicated by the first and second signals. An anti-overload arrangement responds to overloading of the common drive machine for the pumps by altering the operation of the regulators in a way decreasing the stroke of one or both pumps. However, even during the anti-overload stroke decrease, the relative settings of the plurality of stroke-adjustment members are maintained in correspondence with the relative settings of the plurality of control valves.

Regulating arrangement for hydraulic pumps

The multiple-unit pump of this invention has two coaxial pumps each including a rotatable body. One of the bodies is mounted for rotation on a stationary shaft; a second shaft extends through the stationary shaft and carries intermediate the two rotatable bodies a coupling member which rotates with the second shaft and which is provided with recesses into which projections on the two bodies extend, so that the bodies are caused to rotate when the second shaft is rotated.

Multiple-unit pump

A first pump and a second pump have respective mechanical inputs and are operative when the mechanical inputs are driven at constant speed for pumping fluid at an adjustable volumetric flow rate and at a constant non-adjustable volumetric flow rate, respectively, the maximum volumetric flow rate of the first pump being at least as great as that of the second pump. Connecting conduits connect the first pump in hydraulic circuit with an hydraulic consumer. An adjusting mechanism is provided for adjusting the volumetric flow rate of the first pump. A control arrangement is provided for bringing the second pump into and out of hydraulic circuit with the consumer in dependence upon the operation of the adjusting mechanism.

Hydraulic transmission

An external gear type fluid power motor wherein a rotor receives two groups of gears each including a sun gear and one or more planet pinions. The sun gears are coaxial with each other; one thereof is fixed and the other drives an output shaft. Each planet pinion of one group is integral with a planet pinion of the other group or is nonrotatably coupled to it by an oldham coupling. Pressurized fluid is admitted by way of passages machined into a supporting member which is rigid with the housing and rotatably supports one end of the rotor. Such fluid flows through passages in the rotor and rotates the planet pinion or pinions of one or both groups whereby the planet pinion or pinions of one group roll along the fixed sun gear to drive the rotor and to cause the planet pinion or pinions of the other group to roll about the other sun gear which thereby rotates the output shaft. The stubs of the gears can be mounted in discrete bearing members or in covers which form part of the rotor.

Planetary gear motor having fixed and rotating sun gears

A pressure regulator for an adjustable pump has an adjustable member for regulating the amount of fluid delivered by the pump. The position of the adjustable member is adjusted by two pistons of different diameters acting from opposite sides of the adjustable member and in which pressure of the fluid delivered by the pump is directed through a passage controlled by a control valve to one of the cylinder bores in which one of the pistons is closely guided. The control valve is movable by the fluid pressure between a neutral position in which fluid from the pump is prevented from flowing into the cylinder bore of the one piston, and two working positions, in one of which fluid from the pump will flow to the cylinder bore of the one piston while part of the fluid will flow over a throttle to a space at atmospheric pressure, and in the other of which fluid will flow unthrottled from the cylinder bore of the one piston to the aforementioned space.

Pressure regulator for an adjustable pump

The rotary piston pump of a hydrostatic transmission for automotive vehicles has a slide block which is shiftable by a plunger in the cylinder of a follow-up control. The plunger is biased against the slide block by pressurized fluid in a chamber of the cylinder and can be shifted under or against the fluid pressure in the chamber by a control valve wherein a reciprocable spool controls the flow of fluid to the chamber from the pressure outlet of the pump. The spool is shifted in response to changes in fluid pressure at the opposite sides of a flow restrictor installed in a conduit which is connected to the outlet of the pump whereby the spool seals the cylinder of the follow-up control from the tank and from the pressure outlet of the pump before the chamber of the cylinder receives pressurized fluid to thereby change the position of the plunger and slide block.

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Ludwigsburg, Germany

Paul Bosch