Robert Boschgmbh

Siegfried Mayer

Wilhelm Dworak

Karl-Heinz Muller

Wolfgang Talmon

Claus Jons

Kurt Grabow

Ivan Sauer

Jurgen Zorn

Martin Fader

Heinrich Kochendorfer

Dieter Bertsch

Jan Vlemmings

Willy Mahl

Eugen Hartmann

Jorg Anhenn

Guenter Wolff

Paul Bosch

Arno Altpeter

Dieter Weigle

Gunter Wolff

Klaus Griese

Dietrich Schuldt

Manfred Rasper

A pump comprising a housing and two end covers receiving a drive shaft with an eccentric thereon and with a plurality of radial pistons displaceable in radial bores provided in the housing and biased by springs. An inlet passage and an outlet passage are provided in each bore receiving the radial piston. A sealing disc is inserted between the housing and one of the end covers. Sealed through openings for high pressure medium are provided in the sealing disc. The maximal feeding flow of the pressure medium is limited by throttled passages provided in the sealing disc. A pressure control valve is provided, which is connected to an inner chamber of the housing, accommodating the eccentric.

Radial piston pump having sealing disc

A hydraulic gear machine which is particularly suited for use as a reversible hydraulic gear motor includes a pair of gear elements having externally meshing outer peripheral gear portions and stub shafts which are supported in an internal chamber of a housing on respective sleeve-shaped bearings. Two such bearings are arranged at each axial side of the gear elements, one for the stub shaft of each of the gear elements which extends to this axial side. The housing includes a circumferential wall and two end walls. Sealing elements having the configuration of the numeral three are arranged at the interfaces between the bearings and the end walls. The sealing elements are oppositely oriented with respect to a common plane including the axes of rotation of the gear elements at the respective axial sides. Depending on the direction of flow of pressurized hydraulic medium through the machine, a dominating pressure zone builds up at one or the other of the interfaces, the effect of the pressure of the pressurized medium on this pressure zone being to press the bearings in a sealing manner against the gear elements to eliminate gaps therebetween through which the pressurized hydraulic medium could otherwise escape without transferring its energy to the gear elements as useful mechanical energy.

Gear machine with oppositely aligned sealing elements

An arrangement for centering an end wall of a housing of a hydraulic gear machine, such as a pump or a motor, with respect to the open end of an internal chamber provided in a housing body forming the circumferential wall of the housing includes a plurality of pins which are received in a press-fitting manner in bores of the end wall and protrude beyond an end face of the end wall which faces and closes the open end of the chamber in the mounting position. The pins may have contact surfaces which are turned to the same diameter as the corresponding inner surface of the housing body which bounds the open end of the chamber, or they may exactly fit into the open end, or overlap slightly with the inner surface in which event some material displacement or deformation takes place during the assembly of the end wall with the housing body. The bores in the end wall may be equiangularly distributed along a circle centered on an axis coinciding with that of an opening for a drive shaft in the end wall and, in the mounting position, with that of a circular section of the inner surface at the open end. A cylindrical projection may be provided at the other end face of the end wall for clamping the end wall in a clamping arrangement of a material-removing machine during the material-removing operation for producing the contact surfaces of the pins.

Gear machine centering arrangement

A gear machine, such as a gear pump or gear motor, has a housing in a chamber of which there are journalled two gears which mesh with one another. One of the gears is mounted on a drive shaft the end of which is extended outwardly from the housing. The housing is closed at one side thereof with a cover having a stepped bore for receiving the end portion of the drive shaft. The cover is formed with a circumferential projection concentric with the drive shaft and adapted for centering the cover relative to an external element to be coupled with the gear machine. The stepped bore provided in the cover forms a chamber in which a centering ring with a certain radial play is positioned, which centering ring surrounds the drive shaft. A sealing ring is also positioned in the chamber formed in the stepped bore, which sealing ring sealingly closes the housing. The centering ring provides for reliable aligning of the gear machine to the external element adapted to be coupled with the machine.

Fluid-operated gear machine

A gear positive displacement machine has a housing, two gear members, and two bearing members supporting the latter. A gap is formed between an inner wall of the housing and a respective one of the bearing member, the gap increasing in two opposite axial directions. It may start from a central transverse plane of the bearing member. The gap may be formed by a convex peripheral surface of the bearing member or by a convex inner wall of the housing.

Gear positive displacement machine with gaps between bearing members and

An arrangement for producing a connection between two structural parts for preventing any relative movement thereof, consists of a blind bore in the one part and a through bore in the other part, a pin being inserted in fitting manner into the blind bore and projecting into the through-hole. Since the diameter of the through-hole is larger than the diameter of the blind bore an annular space is obtained within the through-hole which is filled out by a sleeve which is deformable through application of ultrasonic waves.

Arrangement for connecting two structural parts

A gear positive displacement machine has two meshing gear members each having two axially opposite shafts, two pairs of bearing members each of which pairs bears one shaft of both gear members, at least one sealing member at one axial end of the gear members, and a supporting element reinforcing this sealing member. The supporting element has a U-shaped cross-section with two arms and a bead at a free end of each arm. The sealing member is inserted by its base side in the supporting member, and the beads of the arms of the latter engage in two grooves formed in the supporting member.

Gear positive displacement machine with U-shaped supporting element for

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 gear-type fluid displacing machine includes a housing having a chamber and two side sections overlying opposite ends of the chamber, a pair of mating gears in the chamber for generating a high pressure area therein as the gears rotate, and annular bearing members surrounding trunnions associated with the gears at opposite ends of the chamber each of the bearing members having an end which faces one of the side sections of the housing and being formed with a groove. The sealing arrangement includes a generally U-shaped resilient sealing element in each of the grooves and having an open side in communication with the high pressure area. The sealing element has at least one wedge-shaped leg which is pressed into sealing contact with an associated side section by its own resilience and by the force exerted by the pressure fluid entering the open side of the element from the high pressure area.

Sealing arrangement for gear-type fluid displacing machines

An external gear pump wherein the gears are installed in an eight-shaped compartment of a central housing section which is flanked by two covers. The outlet port of the housing communicates with two arcuate recesses for metallic inserts which are biased against the adjacent gears by fluid pressure in the outlet port whereby the inserts urge the gears against those portions of the internal surface of the central housing section which are located opposite the recesses. Such portions of the internal surface are formed with narrow first cutouts which communicate with the outlet port. The internal surface is further formed with relatively wide additional cutouts which are located between the first cutouts and the recesses and communicate with the inlet port. The force which is produced by fluid in the cutouts opposes the force which urges the gears against the internal surface of the central housing section to thus reduce the force with which the stubs of the gear shafts are urged against the housing.

Growing community of inventors

Vaihingen, Germany

Siegfried Mayer