Abstract: Two slide valves are located in the discharge end bearing case of a multi-rotor screw machine and independently coact with the sun rotor of the multi-rotor screw machine for controlling capacity and Vi. Movement of the slide valves is in a plane perpendicular to the axis of the sun rotor.

Abstract: In a screw compressor, guide bushings are mounted within bores for the bearings which support rotor shafts for the compressor. First bushings are provided at an inlet casing of the compressor and provide guidance for a slide stop and second bushings are provided in an outlet casing of the compressor to provide guidance for a slide valve. The bushings are also mounted to the inlet and outlet casings to provide centering for two sections of the compressor rotor housing. In one embodiment the first and second bushings provide guidance for a slide valve.

Abstract: In an oil-mist separator included by a compressor, an inlet passage directs a flow axis of a mixture gas including a mist of lubrication oil and a gas to be taken out of the compressor with a pressurized condition when the mixture gas reaches a chamber, and a discharge port for discharging the gas from the chamber opens in the chamber.

Abstract: A feed pipe 26 for a sealing water is connected to a housing of the pump to communicate with an enclosed chamber which is defined between a position in which a helical seal line of screw rotors 17 isolates the enclosed chamber from a suction port 15 of the pump and another position in which the enclosed chamber begins to open to a discharge port 24. Alternatively, a feed pipe for the sealing water is connected to the suction port 15 of the vacuum pump, and the feed pipe 26 is provided with a valve V which opens when the suction pressure of the sealing water becomes lower than −380 mmHg.

Abstract: The invention concerns a cooling device wherein the chamber (2) represents cooling channels arranged in the thickness of the pump cylinder walls. The steam flux (7) generated by the heat to be evacuated reaches the upper end of the condenser (1) and comes out in the form of water in the return branch (6) into the chamber (2). An air flow (5) driven by the fan (3) activates condensation. The sensor (17) acts as a control and safety element.

Abstract: In order to improve a screw compressor for compressing a working medium, comprising an outer housing, two screw rotors which are arranged in the outer housing in rotor bores provided for them and a drive for the screw rotors, in such a manner that the sealing gap is subject to as little variation as possible it is suggested that a compressor screw housing, in which the rotor bores for the screw rotors are arranged, be provided within the outer housing and that a space be arranged between a substantial part of the compressor screw housing and the outer housing.

Abstract: A screw compressor having an unloader valve with a movable valve member, the unloader valve being capable of indicating when the valve member is installed incorrectly. The valve member is manufactured such that if it is installed incorrectly it provides a leakage path sufficiently large to be detected during full load testing of the compressor. When the screw compressor fails the load test, the compressor is partially disassembled, and the valve is reinstalled in the proper orientation and the compressor is re-tested. The valve member leakage path is provided while maintaining low costs for production and assembly of the compressor.

Abstract: A screw rotor compressor is provided that includes two mutually coacting helical screw rotors and a rotor housing (1). The housing (1) includes a first end wall (2) and a second end wall (3) and a barrel wall (7, 11) that interconnects the end walls. The housing (1) has internally the shape of two mutually intersecting cylinders and the first end wall (2) includes an inlet opening (19). The barrel wall (7, 11) includes an outlet opening (6) adjacent the second end wall (3), and also includes a further opening (9) which extends from the outlet opening (6) towards the first end wall (2) and widens over the two mutually intersecting cylinders of the internal shape of the housing.

Abstract: A Lysholm compressor is provided with a rotor 5 in which a spiral tooth groove 5a is formed in order to form a tooth groove space 7, the rotor 5 taking-in and compressing a fluid in the tooth groove space 7, a discharge port 9 which discharges fluid which is compressed by the rotor 5, a bypass path 11 which communicates the discharge port 9 and the tooth groove space 7, and an outlet portion 13 of the bypass path which faces the discharge port 9. The outlet portion 13 has a pipe shape which projects out into the discharge port 9. An outer peripheral portion of an end portion of the pipe-shaped bypass path outlet portion is tapered so as to become narrow toward a distal end.

Abstract: An improved capacity regulating apparatus for compressors is disclosed. The design comprises a chamber, a sliding member coupled to the chamber and a pair of rotors abutting to and below the sliding member. A piston disposed in the cylinder and the sliding member are coupled to a rod, enabling the sliding member to move axially along a portion of the rod. Two opposite guide slots are provided in opposite sides of the sliding member. A lateral slot is provided inside the sliding member to allow the guide slots in communication with each other; also, an axial slot, extending through a bottom wall of the sliding member, is provided inside the sliding member.

Abstract: In order to improve a screw compressor comprising a housing with a rotor chamber, two screw rotors arranged in the rotor chamber, a slide for controlling the capacity adjoining the rotor chamber, an adjusting device comprising a cylinder and an associated control device with which an inflow and a return flow of the medium provided for actuating the cylinder is controllable in a continuous control mode, such that the control device operates reliably, it is proposed that the cylinder chamber comprise a return flow opening and an intermediate return flow opening, and that the control device activate the return flow opening in the control mode for continuous control in a partial control range between an intermediate position and a minimum position, and activate the corresponding intermediate return flow opening defining the intermediate position for continuous control of piston positions outside of the partial control range.

Abstract: A screw compressor having an adjustment slide equipment for adjusting discharge pressure and capacity, respectively, is designed in an advantageous manner in that there is used a “large slide” (24), which is longer than the compressor screws (4, 6) and thereby, via a pointed end portion (14) and in connection with an axial displacement, is operable to effect pressure adjustment at the discharge port (10) without affecting the conditions at the intake end; at the latter, a capacity adjustment can be effected by means of an auxiliary slide (26) which, seen in cross section, forms part of the large slide, and which is separately axially displaceable in a groove (30) therein, such that it is possible to open this groove to a variable degree towards the meeting area of the screw rotors. This basic design in connection with an unusually large diameter of the main slide (24) provides for several advantageous possibilities discussed in greater detail.

Abstract: A rotary device has a first rotor having a recess and a second rotor counter-rotatable to the first rotor and having a radial lobe. A housing in which the rotors are enclosed has a first arcuate recess, an edge of the recess of the first rotor forming a sliding seal with the first arcuate recess during a portion of the rotation of the first rotor. The housing has a second arcuate recess, the lobe of the second rotor forming a sliding seal with the second arcuate recess during a portion of the rotation of the first rotor. Thus, for a portion of the rotation of the rotors, there is defined between the first and second rotors and the arcuate recesses of the housing a transient chamber of volume which progressively decreases on rotation of the rotors. The maximum volume of the transient chamber can be varied.