A pump housing structure of a three-axis multi-stage Roots pump is provided, comprising a first-stage pump housing, a second-stage pump housing and a third-stage pump housing, wherein the first-stage pump housing is provided with a first center axial hole, a first left axial hole and a first right axial hole; a fixed bearing end cover is mounted on the side of the first-stage pump housing, three fixed bearing chambers are provided on the surface of the fixed bearing end cover; the second-stage pump housing is provided with a second center axial hole, a second left axial hole and a second right axial hole, the third-stage pump housing is provided with a third center axial hole, a third left axial hole and a third right axial hole, and the end surface at the outer side of the third-stage pump housing is fixedly mounted with a non-driving end bearing end cover. The present invention can accommodate and fix three axes through three fixed bearing chambers, respectively. Moreover, since the sum of the axial lengths of the second-stage pump housing and the third-stage pump housing is equal to the axial length of the first-stage pump housing, it not only can strengthen the center stiffness of the three axes of the Roots pump, but also can ensure that the total axial expansion is evenly divided, reducing the cumulated amount of thermal expansion at the end of the axis.

A driving structure of a three-axis multi-stage Roots pump comprises a pump body, wherein a gear end cover is mounted at one side of the pump body, an air outlet end moving bearing air sealing unit is mounted on the other side of the pump body, and the bearing end cover is mounted on the pump at the side of the pump body; a driving axis, a first driven axis and a second driven axis are further provided inside the pump body, and the driving axis is connected with the first driven axis and the second driven axis through the gear, respectively; and both ends of the driving axis, the first driven axis and the second driven axis are movably connected to an air inlet end gear mechanical seal driving unit and an air outlet end moving bearing air sealing unit, respectively. The present invention overcomes the deficiencies of the prior art, a fixed bearing limiting unit not only plays a radial supporting role, strengthens the rigidity of an independent axis, but also reduces the diameter of the axis, and at the same time, evenly distributes to the two axial ends in the axial deformation process, avoiding deformation in a single direction, reducing the amount of displacement by nearly half, and also improving the sealing efficiency of the system.

A vacuum pump includes a pump rotor comprising a rotor body, a housing arrangement, a slidable pump vane, and a backing support cone structure. The rotor body comprises a vane slit, a conical ring, a coupling-sided end portion, and a vane-sided end portion. The housing arrangement comprises a static conical ring corresponding to the conical ring. The slidable pump vane is supported in the vane slit. The backing support cone structure is arranged at a front end of the vane-sided end portion and is defined by the conical ring of the rotor body and the static conical ring of the housing arrangement. A coupling structure and a single radial bearing are each arranged at the coupling-sided end portion of the rotor body and a radial bearing is not arranged at the vane-sided end portion of the rotor body so that the rotor body is radially supported cantilevered.

A screw compressor system for a utility vehicle has at least one screw compressor, at least one screw compressor drive and at least one control and/or regulation unit. The control and/or regulation unit is connected to the screw compressor drive and is designed and configured such that it monitors, when the screw compressor is in operation, the ratio of idle time and switched on time of the screw compressor drive and this ratio controls and regulates to a predetermined range.

A screw compressor system for a utility vehicle has at least one screw compressor, at least one screw compressor drive and at least one control and/or regulation unit. The control and/or regulation unit is connected to the screw compressor drive and is designed and configured such that it monitors, when the screw compressor is in operation, the ratio of idle time and switched on time of the screw compressor drive and this ratio controls and regulates to a predetermined range.

A screw compressor for a utility vehicle includes at least one housing and at least one air-oil separator holder arranged at the housing. The air-oil separator holder is manufactured from a non-corrosive material. A relief valve is provided, which is arranged in the air-oil separator holder and by which the interior of the screw compressor can be relieved of pressure.

A method produces a housing of a rotary screw compressor, the housing having at least one housing body and at least one housing cover. The method includes the following steps: bearing seats for at least one screw rotor of the rotary screw compressor are provided in the housing body and in the housing cover; at least one screw borehole for the at least one screw rotor of the rotary screw compressor is provided in the housing body; the housing body and the housing cover are temporarily assembled using at least one alignment tool for ensuring the alignment of the screw rotor central axis with the central axes of the bearing seats and the screw borehole; and at least one bolt insertion opening is provided in both the housing body and the housing cover by at least one common production process.

A screw compressor for a utility vehicle has an air filter with an intake port and an air supply channel for supplying air to the screws of the screw compressor. The intake port is arranged between the air filter and the air supply channel and includes a pocket groove which can maintain the oil.

A compressor includes two rotors opposed to each other in an axial direction, and a vane contacting the rotors. While the vane is moved in the axial direction with rotation of the rotors, the vane is restricted from rotating by a vane groove. The compressor includes compression chambers in which suction and compression of fluid are performed with rotation of the rotors, and a communication mechanism switched between a communicating state in which the compression chambers communicate with each other, and a non-communicating state in which the compression chambers do not communicate with each other.

A compressor includes two rotors opposed to each other in an axial direction, and a vane contacting the rotors. While the vane is moved in the axial direction with rotation of the rotors, the vane is restricted from rotating by a vane groove. The compressor includes compression chambers in which suction and compression of fluid are performed with rotation of the rotors, and a communication mechanism switched between a communicating state in which the compression chambers communicate with each other, and a non-communicating state in which the compression chambers do not communicate with each other.