Abstract: A muffler arrangement includes a muffler with an essentially cylindrical housing having a face end with a central entrance opening and at least one exit opening arranged other than centrally on the face end. Baffles are disposed within the housing, the baffles being concentrically arranged pipe cylinders which extend alternatingly into one another and are closed at one end, for effecting a multiple deflection of gases traveling from the central entrance opening to the at least one exit opening. A coupling structure is secured to the muffler housing, for carrying the muffler in an operating position. The coupling structure has a central passage for connecting the muffler to an exhaust outlet of a machine, and has an other than central channel, surrounding the central passage, for connection to an exhaust gas output conduit for outputting exhaust gases from the muffler arrangement.

Abstract: The invention relates to a dry-running vacuum pump (1) with at least one vertically disposed shaft (2, 3) which is mounted in an upper bearing plate (14) by means of a lubricated rolling bearing (27) situated in an open-topped pot-like component (51); in order to reduce the number of gaps in the area of this bearing (27) it is proposed that with the open-topped pot-like component (51) there be associated an open-bottomed pot-like component (54) fastened to the housing, the wall (55) of which reaches into the pot-like component (51) on the shaft, the rolling bearing's ring (62) that is fixed to the housing being supported on the inside of the said wall.

Abstract: The invention refers to a multiple connection of rotation vacuum pumps having a common housing and drive motor. The vacuum pumps arranged in two rows. Each one of the vacuum pumps has a pump gear, and these gears, together with a drive gear, are arranged such that they form a single row with their teeth drivingly intermeshed. Preferably only inner parts of the pump are located in the housing.

Abstract: A method and apparatus for delivering oil into a pump chamber of a high-vacuum stage of a multi-stage pump. The method includes the steps of sensing a first pressure at an intake region of the high-vacuum stage of the pump, and sensing a second pressure at a discharge region of the high-vacuum stage of the pump. Oil is delivered to the high-vacuum stage of the pump in response to a pressure difference between the first and second pressures. Increased quantities of oil are delivered to the high-vacuum stage of the pump when the pressure difference exceeds a predetermined value. A gas ballast may also be delivered to the high-vacuum stage of the pump when the pressure difference exceeds this predetermined value. The apparatus may include a diaphragm valve including a diaphragm mounted between subchambers that are respectively in fluid communication with the intake and discharge regions of the high-vacuum stage of the pump.

Abstract: The invention is directed to a method for the operation of a twin shaft vacuum pump (1) having two rotors (4, 5; 6, 7; 8, 9) that rotate synchronously and in non-contacting fashion in a pump chamber, each being provided with a respective projection (38) and a recess (39), the one of said rotors controlling an admission opening (32, 35) and the other controlling a discharge opening (33, 37, 42); the invention is also directed to a twin shaft vacuum pump suitable for the implementation of the method; in order to be able to admit flushing gas into a twin shaft vacuum of this species during operation as well, it is proposed that flushing gas be admitted into the respectively diminishing pump volume via an orifice (45) that is controlled such by the rotor at the discharge side that the respective pump volume is closed both toward the admission opening (35) as well as toward the discharge opening (42) at the moment the flushing gas is supplied.

Abstract: A twin-shaft vacuum pump including a rotor pair mounted for rotation in a pump chamber. The rotor pair together with the chamber wall define a suction side and delivery side of the pump chamber. In order to prevent solid particles suspended in pump fluid from settling in the chamber, the invention provides a flushing gas outlet orifice disposed on the delivery side of the pump chamber and adapted to be connected to a source of flushing gas. The solid particles can thus be held in suspension and conveyed from the pump with the assistance of flushing gas supplied through the orifice.

Abstract: The invention refers to a multiple connection of rotation vacuum pumps having a common housing and drive motor. The vacuum pumps arranged in two rows. Each one of the vacuum pumps has a pump gear, and these gears, together with a drive gear, are arranged such that they form a single row with their teeth drivingly intermeshed. Preferably only inner parts of the pump are located in the housing.

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.

Abstract: A multistage vacuum pump with a case with at least two pump chambers in the case, and with at least one passage connecting the pump chambers together. To detect fouling in the especially sensitive connecting passages in a simple manner, it is proposed to configure the passages as part of bores leading to the outside, which can be closed with a plug.

Abstract: A twin-shaft vacuum pump having a pair of shafts, at least one pump chamber, a pair of rotors disposed in the or in each pump chamber and mounted on the shafts, and housing members defining the pump chamber or chambers, a synchronization mechanism composed of two gears disposed in a side chamber, a drive motor, and a transmission mechanism connecting the drive motor to one of the shafts. In order to simplify installation and servicing of the pump, the shafts are mounted vertically. The side chamber, synchronization mechanism, and transmission mechanism are disposed below the lower rotor pair.

Abstract: A filter cartridge for cleaning oil of an oil sealed vacuum pump which comprises a cartridge housing, the cartridge housing being releasably mounted to the vacuum pump; filter materials including at least two types of filters having different characteristics, the filter materials including the filters being disposed in the cartridge housing.

Abstract: Disclosed is a system for separating impurities from a hydrogen-free fluorinated lubricant. The lubricant is passed through a filter apparatus containing an adsorbing material. The lubricant is then passed into a degasser unit to remove volatile impurities from the lubricant. The degassing unit has an area of closed suction. A pressure measuring device measures the pressure in the closed area and, based on this measurement, a control apparatus controls the degassing unit. A monitoring unit monitors the quality of the filtered lubricant.

Abstract: A vacuum pump and trap combination in which the trap is configured in the manner of a siphon and comprises a tube immersed in trap liquid but having an opening lying above the trap liquid level. The tube has a wall section lying below the trap liquid level and having perforations therein to admit different amounts of trap liquid in relation to the rate of discharge gas flow, thereby preventing frothing of the trap liquid.

Abstract: An oil-sealed vacuum pump has an oil circuit which has an externally located oil filter that may be operatively connected to or disconnected from the oil circuit by a coupler. The coupler has a rotatably supported valve disc having a first face oriented towards oil circuit ports in the pump and a second face oriented towards the filter. The valve disc further has spaced first and second apertures passing therethrough and a groove provided in the first face and oriented approximately perpendicularly to an imaginary line connecting the first and second apertures with one another.

Abstract: A rotor for a rotary slide-vane vacuum pump and a method of producing same comprises providing two rotor sections, each having a shaft stub, a rotor portion and a plane or contact surface produced by lathing, forming axial slot portions for accommodate one or more slide vanes through the contact surfaces, assembling the two rotor sections by the use of an assembling jig and fixedly joining the sections together and finishing the external surfaces of the assembled rotor with respect to at least one of length and diameter while the rotor is held in one and the same fixture.

Abstract: An oil-sealed vacuum pump comprises an oil circuit for supplying a pump chamber and bearings of the vacuum pump with oil. The oil circuit includes first and second branch conduits leading to the bearings and the pump chamber, respectively. The vacuum pump further has an oil pump coupled to the oil circuit for driving oil therethrough, a valve assembly coupled to the oil circuit for shutting off oil supply to the pump chamber during standstill of the vacuum pump, and a pressure reducer coupled to the oil circuit for reducing the oil pressure to environmental pressure. The first branch conduit leading to the bearings is situated upstream of, and the second branch conduit leading to the pump chamber and the valve assembly are situated downstream of the pressure reducer as viewed in the direction of oil flow in the oil circuit.

Abstract: A vacuum pump comprises a suction nipple valve including a cylinder, a piston slidably received therein and a movable valve closing member operatively connected to the piston. The vacuum pump further has a pressure medium conduit having a first end communicating with the cylinder; an inlet opening at a second end of the conduit for pressure medium to flow through the inlet opening to the piston; a control arrangement for closing and opening the inlet opening dependent upon run or standstill of the vacuum pump. In the closed state of the inlet opening an oil quantity is maintained above the inlet opening.