Provided is a gear pump or a motor provided with: a casing internally provided with a gear housing compartment in which a pair of gears are housed; a side plate interposed between the casing and the gears; and a gasket which is disposed on a non-slide surface, and which divides a space between the non-slide surface and the casing into a high pressure side and a low pressure side. The gear pump or the motor is configured such that, in order to discover early the mounting of the side plate in a wrong attitude, such as the upper and lower sides thereof being reversed or the high pressure portion side and the low pressure portion side being reversed, flow rate efficiency is decreased when the side plate is in an attitude other than a predetermined attitude, compared to when the side plate is in the predetermined attitude.

A method for fixing rotary pistons in a rotary piston pump and a method for dismantling rotary pistons of a rotary piston pump, where the rotary piston pump has two counter-rotating rotary arranged in a pump space on drive shafts. The rotary pistons each include a seating for the drive shafts. The respective drive shaft is arranged and fixed with an end region in the seating of the respective rotary piston. A diameter of the drive shafts in the end region can be widened elastically. In an operational state, in which the rotary pistons are arranged on the respective drive shafts, a frictional connection is formed between the respective seating of the rotary piston and the end region of the respective drive shaft.

The invention relates to a rotary piston engine comprising a housing which forms an interior space, two rotary pistons which are arranged in the interior space, an inlet opening for introducing a fluid into the interior space, and an outlet opening for the fluid, which is located in the interior space on a side opposite the inlet opening. Each rotary piston comprises at least two sealing strips and at least two recesses on the outer circumference thereof, wherein the shapes of the recesses and the sealing strips are selected to engage the sealing strips of a respective rotary pistons in the recesses of the respective other rotary piston. In addition, the sealing strips are dimensioned in the radial direction to sealingly contact an inner wall of the housing. The invention also relates to a corresponding method for operating a rotary piston engine.

A rotary pump is provided for fluid transfer. The pump includes a planar housing, an elongated rotor, a pair of double-concave blades, fore and aft cover plates, and a gear box. The housing has a circular center cavity, and a pair of circular lateral cavities overlapping the center cavity and disposed along a longitudinal axis. The rotor is disposed on a rotor shaft along a rotation axis perpendicular to the longitudinal axis within the center cavity. The blades flank the rotor and are disposed within their corresponding lateral cavity and turn on corresponding blade shafts parallel to the rotor shaft. The fore and aft cover plates flank the housing along the rotation axis to cover the center and lateral cavities. The blades turn opposite from the rotor.

The application relates to a device for conveying a medium having a working machine (2) and multiple carrier shafts (25, 35) with transport elements (22, 32) for the medium to be conveyed arranged on them, along with a drive (3) that sets the carrier shafts (25, 35) in rotation, wherein the drive (3) has multiple driven shafts (20, 30), each of which is coupled with not less than one carrier shaft (25, 35).

In order to prevent deterioration in performance of an oil-free screw compressor and scuffing caused by rust, surfaces of both male and female rotors are coated with heat-resistance coatings containing a solid lubricant. A coating contains Polyimide resin to which Molybdenum disulfide, as a solid lubricant, and Aluminum oxide and Titanium oxide, as additives, are added. Accordingly, it is possible to realize a coating that is higher in heat resistance and longer in lifetime than a conventional one.

In order to prevent deterioration in performance of an oil-free screw compressor and scuffing caused by rust, surfaces of both male and female rotors are coated with heat-resistance coatings containing a solid lubricant. A coating contains Polyimide resin to which Molybdenum disulfide, as a solid lubricant, and Aluminum oxide and Titanium oxide, as additives, are added. Accordingly, it is possible to realize a coating that is higher in heat resistance and longer in lifetime than a conventional one.

The present invention relates to an energy transforming unit adapted to convert reciprocating forces into rotating axle movements on at least one force transmitting axle and/or into electrical power. The unit comprises at least one restriction device which is directly connected to the force and which is arranged to forward the incoming reciprocating forces into a movement over at least one conversion module. The energy transforming unit is characterized in that the at least one restriction device is delimiting one, by the energy transforming unit enclosed reciprocating volume which entirely or partly passes through the at least one conversion module. The reciprocating volume can comprise a non-compressible fluid arranged to forward the incoming forces into a reciprocating fluid movement over the at least one conversion module and/or the reciprocating volume can comprise at least one mechanical force transmitting arrangement adapted to the at least one conversion module. The unit further comprises a compact central unit which at least partly encloses the at least one conversion module.

The present invention relates to an energy transforming unit adapted to convert reciprocating forces into rotating axle movements on at least one force transmitting axle and/or into electrical power. The unit comprises at least one restriction device which is directly connected to the force and which is arranged to forward the incoming reciprocating forces into a movement over at least one conversion module. The energy transforming unit is characterized in that the at least one restriction device is delimiting one, by the energy transforming unit enclosed reciprocating volume which entirely or partly passes through the at least one conversion module. The reciprocating volume can comprise a non-compressible fluid arranged to forward the incoming forces into a reciprocating fluid movement over the at least one conversion module and/or the reciprocating volume can comprise at least one mechanical force transmitting arrangement adapted to the at least one conversion module. The unit further comprises a compact central unit which at least partly encloses the at least one conversion module.

A motor includes a shaft rotatable about an axis, an engaged component engaged by the shaft, a sleeve fixed to the shaft to rotate therewith, and a seal at least partly circumscribing the shaft. The shaft includes an engagement region presenting a substantially variable outer shaft surface that at least in part engages the engaged component. The sleeve includes a first section that at least partly circumscribes and engages the engagement region of the shaft. The first section of the sleeve presents an outer seal-engaging surface and an outer bearing-engaging surface. The seal and the bearing each at least partly circumscribe the engagement region of the shaft and the first section of the sleeve to engage the seal-engaging surface and the bearing-engaging surfaces, respectively, of the sleeve.