A compressor includes a shell, a compression mechanism and a fitting. The shell includes an opening and defines a chamber. The compression mechanism is disposed within the chamber of the shell. The fitting is attached to the shell at the opening. Working fluid flowing through the fitting flows to the compression mechanism. The opening is partially defined by a first edge and a second edge. The first edge includes a first planar surface and the second edge includes a second planar surface that faces the first planar surface. A first portion of the fitting extends at least partially into the opening and a second portion of the fitting abuts against the first and second edges.

A scroll compressor, includes: a pressure container; a frame including a hollow cylindrical portion and a bottom surface portion formed integrally with each other, the hollow cylindrical portion having an outer peripheral surface fixed to an inner peripheral surface of the pressure container; an orbiting scroll including a first base plate and a first spiral tooth formed on one surface of the first base plate, the orbiting scroll being rotatable in a hollow portion of the hollow cylindrical portion; a fixed scroll including a second base plate with a second spiral tooth, the second spiral tooth being meshed with the first spiral tooth; and a second suction pipe communicating with the hollow portion of the hollow cylindrical portion.

The present invention relates to rotary screw positive displacement machines used as a vacuum pump wherein additional intake air is provided allowing cooling to the invention which permits extended operation at extreme vacuum pressure. The rotary screw nature of the vacuum pump allows operation without additional lubrication with the additional intake air ensuring that thermal expansion will not disrupt the tight tolerances of the invention. The invention allows simultaneous operation as a vacuum pump and air compressor.

A scroll device has a fixed scroll, and orbiting scroll, and at least one cooling chamber configured to receive coolant to cool the fixed scroll or the orbiting scroll. A flexible conduit that curves around an orbital axis of the orbiting scroll may transfer coolant into or out of the at least one cooling chamber. The scroll device may have a motor with a motor jacket configured to receive coolant for cooling the motor. One or more involutes of the scroll device may comprise a wall coated or plated with a solid abrasion-resistant lubricant.

A check valve includes a valve seat portion and a reed valve element and is received in a receiving hole of an intermediate pressure refrigerant supply passage that is placed adjacent to a flow inlet of an injection port, through which a refrigerant of an intermediate pressure is injected into a compression chamber. A center of the flow inlet of the injection port is offset from a central axis of a valve seat passage formed in the valve seat portion.

An Oldham coupling structure for a scroll compressor decreases Oldham coupling pressure loading without increasing compressor diameter or significantly increasing orbiting scroll or Oldham coupling inertia. The Oldham coupling key height and area are increased by recessing the key face into the ring portion of the Oldham coupling, increasing the key height and adding pads to the involute side of the orbiting scroll base plate to extend the key slot, potentially resulting in reduced compressor diameter and/or reduced orbiting scroll and Oldham coupling inertia.

Method for treating outlet air in a pneumatic waste conveying system, in which the outlet air is at least partly the conveying air to be used in waste conveying. In the method in a first phase additional air is brought into the body of conveying air in the partial-vacuum generator of the pneumatic waste conveying system before the output aperture of the partial-vacuum generator, and that in the method in a second phase additional air is brought into the body of outlet air as a consequence of the suction effect brought about by the outlet air in such a way that the outlet air and the additional air mix with each other at least partly. The invention also relates to an apparatus.

A method is provided for controlling a temperature of a vacuum pump of a dry vacuum pump type subjected to variable pumping loads, the pump including a stator, a pumping stage, two shafts extending into the stage and respectively bearing a rotor to rotate synchronously in opposite directions in the stator and to drive a gas from a suction inlet to a delivery outlet, a cooling element coupled to the stator, a temperature sensor to measure a stator temperature, and a controller to control the stator temperature by the cooling element and the temperature sensor; and the method including controlling the pump temperature by the cooling element based on a temperature setpoint and a measurement of the stator temperature, and monitoring whether a value of a pumping load parameter is below a load threshold and, if so, increasing the setpoint. A vacuum pump and a system are also provided.

A pumping system is provided, including a rough-vacuum pump; a Roots vacuum pump including a pumping stage having a stator inside which two Roots rotors are configured to rotate synchronously in opposite directions to drive a gas to be pumped between an inlet orifice and an outlet orifice; and a pipeline connecting the outlet orifice to an intake of the rough-vacuum pump, a shortest distance between an edge of the outlet orifice and each of the Roots rotors in the pumping stage being less than 3 cm, and the outlet orifice being situated at the end of an upstream tube of the pipeline that passes into the pumping stage.

A liquid ring pump manifold comprising an integrated non-return valve, the integrated non-return valve being configured to permit flow of fluid through the liquid ring pump manifold in a first direction and to prevent or oppose flow of fluid through the liquid ring pump manifold in a second direction, the second direction being opposite to the first direction.