Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: What follows is the description of an improved hydraulic apparatus for the automatic adjustment of the inclination of the headlights of a motor vehicle, the adjustment being a dependent function of the axle load. The apparatus has a level sensor at each axle and each level sensor contains one metering piston and two positioning pistons. The rear axle level sensor is connected via two separate hydraulic lines to the front axle sensor, and the front axle sensor is in turn connected via two separate hydraulic lines to the positioning elements of the headlight housings. The internal construction of the two level sensors is substantially identical and is chosen such that the system is also suitable for manual adjustment.