An improved screw-spindle pump, particularly for cooling systems, includes a first screw, a second screw and a pump housing, inside which the first screw and the second screw are rotatably housed between the first screw, the second screw and the pump housing, being defined pumping chambers adapted to move, as a consequence of the rotation of the first screw and the second screw, a fluid from a suction area to a delivery area of the pump.

The pump housing housing the first screw and the second screw is made in one piece.

A scroll compressor (1) including an enclosure (2); a compression section (6) arranged within the enclosure (2), the compression section (6) has a fixed scroll element (7) having a first baseplate (11) and a first wrap portion (12) extending from the first baseplate (11), and an orbiting scroll element (8) having a second baseplate (13) and a second wrap portion (14) extending from the second baseplate (13), the fixed and orbiting scroll elements (7, 8) being intermeshed to form compression chambers (15); and a driving section (16) coupled with the orbiting scroll element (8) for moving the orbiting scroll element (8) in an orbiting motion during operation of the scroll compressor (1). At least one of the fixed and orbiting scroll elements (7, 8) is made of solid solution strengthened ferritic ductile iron.

An example apparatus includes an outer rotor having a first axial face and a second axial face opposite the first axial face, wherein the first axial face comprises a circumferential contour defining a plurality of lobe faces, and wherein the second axial face comprises a transformed circumferential contour defining a corresponding plurality of lobe faces, where the transformed circumferential contour comprises at least one of a scale transformation of the circumferential contour or a rotational transformation of the circumferential contour; and an inner rotor configured to rotate eccentrically within the outer rotor, thereby forming a gerotor element for a fluid pump.

The present invention provides a vertical, axial flow oil pump (10). The oil pump includes: a casing (11), the casing having a cylindrical shape as a whole and being able to rotate around its own central axis (O); a suction port (12), located at a lower end of the casing in an axial direction, and configured to suck oil into the oil pump; a discharge port (13), located at an upper end of the casing in the axial direction, and configured to discharge the oil from the oil pump to outside; and an impeller (14), provided in and formed integrally with the casing. The impeller rotates together with the casing when the casing rotates, so that the oil is flowed from the suction port to the discharge port. The present invention also provides a scroll compressor having the oil pump.

A vibration suppressing piping member suppresses vibration caused by a pulsating discharged gaseous fluid. The piping member includes a tubular portion and flange portions at both ends of the tubular portion. A bent portion is formed between the two flange portions. The two flange portions are directly connected to each other.

A screw compressor includes a male rotor and a female rotor enclosed in a casing inside which they counter-rotate, to drive the male rotor from a motor, a gas passes through an intake duct created between the two rotors, and the rotation closes this intake duct and the compressed gas is pushed towards a delivery. Each rotor includes a rotation shaft which rotates in the case due to special bearings which is surrounded by helical propellers which engage each other, the propellers being made to reduce progressively the space between rotors and casing, so that the gas sucked in by the suction duct compresses in the direction of the delivery. The helical propellers are made of a polymeric material.

A cast for producing end plates for a pump assembly, the cast comprising a base portion and a pair of projections, the pair of projections providing material to machine bearing assembly housings for accommodating drive and idler shafts in the pump assembly. Also provided is an inner plate bushing for an end plate in a pump assembly, the inner plate bushing comprising a collar extending from a flange, the collar to be inserted into a mounting recess in the end plate with the flange seating flush with a surface of the end plate, the surface area of an end of the collar being larger than an inner surface of the flange.

Disclosed are a movable scroll device for a scroll compressor and a method for manufacturing same. The method includes: manufacturing the movable scroll device by means of casting steps, so that the movable scroll device includes a movable scroll end plate, with a movable scroll blade provided on a first side face of the movable scroll end plate; and a hub vertically extending outwards from the middle of a second side face of the movable scroll end plate; and fabricating at least one centroid adjustment recess on the hub. By the method, the centroid of the movable scroll device can be adjusted in a more flexible, precise, active and targeted manner.

An oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of the screw rotors; a shaft seal device including an oil seal portion and an air seal portion; an atmosphere open hole formed in the shaft seal device; at least one communication hole formed in the rotary shaft; and an annular space communicating the atmosphere open hole with the at least one communication hole communicate with each other. The annular space includes an inner peripheral annular space formed on an inner peripheral side of the casing. Assuming an open cross-sectional area of the inner peripheral annular space as S1, a total open cross-sectional area of the communication holes as S2, an open cross-sectional area of the i-th communication hole out of the communication holes as S2i, and the number of communication holes as n (n being a natural number of 1 or more), a following relationship is satisfied.

[00001]$S.Math..Math.1\geqq S.Math..Math.2=\underset{i=1}{\overset{n}{.Math.}}.Math..Math.S.Math..Math.2.Math.i$

A vacuum booster assembly includes, but is not limited to, a booster housing defining a booster chamber and including a gas inlet and a gas outlet; a first rotor positioned within the booster chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the booster chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10.sup.−6 in/in*K) to about 13 (10.sup.−6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the booster chamber includes a coating.