Abstract: Compression of water vapour as R718 is disclosed with and without addition of additives as an aqueous solution in rotational displacement machines, i.e. refrigeration, air-conditioning and heat pump technology. To largely avoid over or under-compression, it is proposed for the easiest possible adaptation of the currently effective internal volume ratio as so-called iV value in the displacer that the compressor housing starting from the outlet side with rotor profile length LR over a length LiV comprises planar, i.e. flat iV disks (3j) with the index j for 1?j?n; n is the number of disks; n?1 with a width bj per iV disk having planar surfaces PF preferably perpendicular to the neutral axis AN. The iV disks are displaced in a targeted manner individually by movement control devices (5j) per iV disk in each case by a distance si where 0<si?sj.

Abstract: Compression of water vapour as R718 is disclosed with and without addition of additives as an aqueous solution in rotational displacement machines, i.e. refrigeration, air-conditioning and heat pump technology. To largely avoid over or under-compression, it is proposed for the easiest possible adaptation of the currently effective internal volume ratio as so-called iV value in the displacer that the compressor housing starting from the outlet side with rotor profile length LR over a length LiV comprises planar, i.e. flat iV disks (3j) with the index j for 1?j?n; n is the number of disks; n?1 with a width bj per iV disk having planar surfaces PF preferably perpendicular to the neutral axis AN. The iV disks are displaced in a targeted manner individually by movement control devices (5j) per iV disk in each case by a distance si where 0<si?sj.

Abstract: The invention relates to a spindle compressor designed as a twin-shaft rotary displacement machine for delivering and compressing flow media, particularly steam. It comprises a pair of spindle rotors in a compressor housing (1) comprising an inlet collecting space (11) and an outlet collecting space (12). The centre distance of the pair of spindle rotors is at least 10% longer on the inlet-side end than on the outlet-side end. Each of the two spindle rotors (2, 3) is driven by an electric motor (18, 19), and an electronic synchronisation controls the electric motors (18, 19) such that the spindle rotors (2, 3) rotate in a contact-free manner.

Abstract: A displacement compressor system for the refrigerant R718 includes a compressor machine, an evaporator, and a condenser. The open compressor machine is designed as a spindle compressor in the form of a double-shaft rotation displacement compressor for displacing and compressing gaseous conveying media. The displacement compressor has a spindle rotor pair which is arranged in a compressor housing and is designed with an electronic motor pair spindle rotor synchronization function. The compressor machine is arranged between the evaporator and the condenser.

Abstract: The invention relates to a spindle compressor without operating fluid in the working space with a 2-tooth spindle rotor and a 3-tooth spindle rotor in a surrounding compressor housing-and preferably non-parallel rotation axes of the two spindle rotors, in particular for use in compression refrigeration machines.

Abstract: The invention relates to a spindle compressor without operating fluid in the working space with a 2-tooth spindle rotor and a 3-tooth spindle rotor in a surrounding compressor housing-and preferably non-parallel rotation axes of the two spindle rotors, in particular for use in compression refrigeration machines.

Abstract: A spindle rotor pair of a spindle compressor has a two-toothed spindle rotor and a three-toothed spindle rotor meshing the other without contact. The wrap angle related to the two-toothed spindle rotor is at least 800 angular degrees. A range of at least 30 m/sec is achieved as the mean circumferential speed of the rotor head. In the transverse section, both spindle rotors have arc sectors and cycloid profile contour flanks. In the case of the two-toothed spindle rotor, they are primarily above its gear-tooth pitch circle and of convex design, however, in the case of the three-toothed spindle rotor, they are below its ear-tooth pitch circle and of concave, i.e., hollow, design. Preferably, the transverse sections of each spindle rotor are symmetrical in a way that in each transverse section, the centre of gravity of the profile surfaces comes to lie on the respective rotor pivot point.

Abstract: The invention relates to a dry-compressing dual-shaft rotary displacement screw spindle pump machine for delivering and compressing gases. The spindle rotor pair therein includes multiple stages, having a primary delivery thread, a secondary delivery thread and a gas outlet collector chamber therebetween. The primary delivery thread head circle diameter decreases in the gas outlet direction, while the foot circle diameter thereof increases correspondingly for an application-specific matching inner “integral” compression ratio. The secondary delivery thread nominal delivery direction is opposite to the primary delivery thread nominal delivery direction. The secondary delivery thread is implemented such that the actual gas flow direction is opposite to the nominal delivery direction thereof, and is always directed away from the gas outlet plenum, having a gas permeation under ambient pressure just as the space in the gearbox.

Abstract: The invention relates to a dry-compressing dual-shaft rotary displacement screw spindle pump machine for delivering and compressing gases. The spindle rotor pair therein includes multiple stages, having a primary delivery thread, a secondary delivery thread and a gas outlet collector chamber therebetween. The primary delivery thread head circle diameter decreases in the gas outlet direction, while the foot circle diameter thereof increases correspondingly for an application-specific matching inner “integral” compression ratio. The secondary delivery thread nominal delivery direction is opposite to the primary delivery thread nominal delivery direction. The secondary delivery thread is implemented such that the actual gas flow direction is opposite to the nominal delivery direction thereof, and is always directed away from the gas outlet plenum, having a gas permeation under ambient pressure just as the space in the gearbox.

Abstract: A screw-type vacuum pump (1) includes a pump housing (2, 6) with rotors (3, 4). A liquid cooling system cools the rotors and a drive motor (9). In order to improve the cooling of said pump, an external air-flow impelled cooling system is also provided for the pump housing (2, 6).

Abstract: A screw-type vacuum pump (1) includes a pump housing (2, 6) with rotors (3, 4). A liquid cooling system cools the rotors and a drive motor (9). In order to improve the cooling of said pump, an external air-flow impelled cooling system is also provided for the pump housing (2, 6).

Abstract: The invention relates to the production of screw pump rotors comprising a pitch and/or depth of teeth which can be modified along the axis of the rotor. By means of a simple profiled machine tool (7), a first part of the profiled flank contour is clearly defined along the rotor axis (8) by means of its specific tool guide mechanism, and is then produced in a definitive manner. The remaining second part of the profiled flank contour is then determined according to the rolling movement of the pair of rotors according to the first part of the profiled flank contour carried out by the tool, by means of an approximation which is as precise as possible. It is thus possible to obtain transversally different profiled contours according to the pitch and/or depth of teeth which can be modified along the axis of the rotor. A disk milling cutter is selected to be used as a profiled machine tool.

Abstract: The invention concerns a screw pump (10) that is configured as a dual-shaft positive displacement motor and that comprises two positive displacement spindle rotors (1 and 2) rotating in opposite directions and having external toothing. In order to provide a quiet and simple drive mechanism for said rotors (1 and 2) while ensuring synchronization and increased rotational speed, contrate gear-like gearwheels (3 and 4) are mounted on both rotors (1 and 2) rotating in opposite directions or the rotor spindles in a corresponding plane, in which a larger contrate gear-like driving toothed wheel (5) engages in such a way that both spindle rotors (1 and 2) are driven in opposite directions at an increased rotational speed, wherein said contrate gear similarity also includes a crown gear with internal and external toothing working in connection with front toothed wheels or bevel gears and the possibility that only the driving toothed wheel (5) or only the driven gearwheels (3 and 4) are contrate gear-like.

Abstract: A dry-compressing screw pump in the form of a two-shaft positive displacement pump. A first and a second rotor spindle are disposed parallel to each other. The rotor spindles are hollow. A cooling medium is fed at a first front face of the rotor spindles and evacuated at a second front face of the rotor spindles. A cooling medium feeding and evacuation means is connected to an external cooling medium circuit. The inner diameter of the rotor spindles monotonously increases from the first front face toward the second front face so that the cooling medium is conveyed from the first front face to the second front face substantially under the influence of centrifugal force acting on the cooling medium due to the rotation of the rotor spindle.

Abstract: The invention provides a two-rotors screw compressor having active cooling means on the pressure side of the motive rotor.

Abstract: A vacuum pump contains two rotary displacement rotor (8) that engage each other, in particular in a convoluted manner, inside in expansion chamber through which flows a stream in the axial direction. The rotors are mounted in cantilever at the delivery side and are linked each to a driving motor (35, 36). Each rotor (8) forms together with its shaft (20), a stationary bearing body (7) and a bearing (21, 22) delimited by the shaft (20) and the bearing body (7) a module that may be removed as a single unit from the housing (3). The rotor (35) of the driving motor is preferably also part of said module.

Abstract: In a displacement machine for compressible media having at least two rotors (14a-c) which are configured as profiled bodies and whose profiles engage with one another in the manner of gearwheels during rotation, the individual rotors are respectively driven by their own electric motors (9a-c) and are kept synchronous in rotational speed and angular position by electronic closed-loop and/or open-loop control units (1; 25a-c) in accordance with the transmission ratio of the displacer unit stage. The electronics can be employed for monitoring further operating data of the pump and also for matching the pump output by changing rotational speed. It can also be used as an overload protection. The rotational speeds and rotational attitudes of the rotors are controlled individually and independently of one another, the required attitude values being specified to the individual control units (25a-c) by means of a main control unit (1).

Abstract: A dual rotor Roots type vacuum pump has an improved rotor profile contour resulting in high area efficiency, high volumetric efficiency, reduced backstreaming and simplified economical manufacturing which yields a compact, cost effective pump.

Abstract: A double-shaft vacuum pump with pistons (3,4) rotating without contact in the pump chamber (8) and with synchronization gears (16, 17) located in a side chamber (15). In order to dispense with an oil supply in the side chamber the teeth of the synchronization gears (16, 17) are shaped in such a way that contact between the tooth flanks (26) is limited to the immediate vicinity of the pitch circle (29). If any lubrication is needed, it can be supplied by bearing grease suitable for vacuum applications. The side chamber cover (27) is preferably shaped as a "figure-8" to conform to the peripheries of the synchronization gears (16, 17), and a cooling system for the gears may be provided.

Abstract: A twin-shaft vacuum pump includes a pump chamber, a pair of rotary pistons disposed in the pump chamber, and plates which laterally delimit the pump chamber, and a housing ring which peripherally delimits the pump chamber. In order to increase the ability of the pump to withstand thermal stresses, the housing ring and the rotary pistons are made of different materials, with the coefficient of expansion of the piston material being lower than the coefficient of expansion of the housing material. Other improvements include cooling of the lateral end plates, cooling of the rotors, and the provision of sleeves which serve to fix the position of the rotors on the shafts and which are composed of a material whose coefficient of expansion is lower than that of the rotor material.