A pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), has a drive motor (40) and a rotary piston pump (2) having two rotor units (10, 20) on rotatably mounted rotor shafts (11, 21), connected to rotor gear wheels (12, 22). A drive pinion (32) of a drive shaft (31) coupled to one of the rotor gear wheels (12) and is received in a recess (81) of the motor shaft (41).

A scroll compressor includes: a shell forming an outer case, a fixed scroll and an orbiting scroll stored in the shell, a frame holding the orbiting scroll, a thrust plate between the orbiting scroll and the frame, and a thrust oil return pipe fixed to the frame. The shell forms an oil reservoir in which lubricating oil is reserved. The orbiting scroll and fixed scroll form a compression chamber. Lubricating oil flows through the thrust oil return pipe to return to the oil reservoir. A hole portion on the thrust plate passes from a first surface portion that slidably contacts the orbiting scroll to a second surface portion facing the frame. The thrust oil return pipe is inserted into the hole portion and fits in the thrust plate. An upper end portion of the thrust oil return pipe does not protrude from the first surface portion of the thrust plate

The invention provides an engine for obtaining kinetic rotational energy from the explosive decomposition of individual cartridges of an energetic material. The cartridges are individually ignited as needed, producing a bolus of hot, expanding gas, the energy of which is captured by a piston moving in a circular track. Each cartridge ignition produces a single circuit of the piston around the track. A gearing mechanism transfers the angular momentum of the piston to a flywheel. The engine may be coupled to an electrical generator to form a portable, on-demand electric generator system.

A multi-stage dry Roots vacuum pump, including a pump body, multi-stage Roots working units and a plurality of drive components. The pump body is provided with a plurality of independent working chambers, and airflow channels communicating the various working chambers; the airflow channels are communicated with outside; the Roots working units of each stage include driving Roots rotors and driven Roots rotors; the driving Roots rotors and driven Roots rotors are positioned in the working chambers; and the various drive components are respectively used for driving the driving Roots rotors and driven Roots rotors positioned in the various working chambers to rotate towards opposite directions at the same rotating speed. The Roots working units of various stages may be randomly distributed at various positions of the pump body on premise of ensuring that the airflow channels can communicate the working chambers of each stage.

A screw compressor for a utility vehicle has at least one housing with at least one housing cover and with at least one rotor housing, at least one baffle plate and at least one seal. In the assembled state, an oil sump is present in the housing, wherein, with regard to the assembled state, the seal is arranged between housing cover and rotor housing and projects out of the oil sump. The seal at least partially separates the interior of the housing cover from the interior of the rotor housing. With regard to the assembled state, in the case of a substantially horizontal orientation of the screw-type compressor and in the case of a substantially horizontal orientation of the oil sump, the baffle plate is oriented substantially parallel to the upper level of the oil sump.

A multistage compression system uses refrigerant and oil. The multistage compression system includes a low-stage compressor that compresses the refrigerant, a high-stage compressor that further compresses the refrigerant compressed by the low-stage compressor, refrigerant pipes that-introduce the refrigerant compressed and discharged by the low-stage compressor into a suction part of the high-stage compressor, a pressure reducing element disposed between the refrigerant pipes, an accumulator disposed between the refrigerant pipes at a downstream side of the pressure reducing element and at an upstream side of the high-stage compressor, and an oil discharge pipe. The oil discharge pipe discharges the oil in the low-stage compressor. The oil discharge pipe connects the low-stage compressor and a portion of the refrigerant pipes. The portion of the refrigerant pipes is on a downstream side of the pressure reducing element and an upstream side of the accumulator.

A package-type fluid machine includes a compressor unit including a compression portion that compresses a fluid, a motor that drives the compression portion, and a cooling fan that is driven by the motor; a machine chamber in which the compressor unit is disposed; an inverter chamber which is adjacent to the machine chamber and in which an inverter is disposed; a partition wall that partitions off the machine chamber from the inverter chamber and has an opening; and an inverter intake port that is disposed in the inverter chamber to take in a cooling gas. The cooling fan is disposed on a side of the machine chamber, the opening being located on the side. The cooling fan is driven to cause the cooling gas to flow from the inverter intake port to the opening to cool the inverter.

A scroll compressor that includes a housing and scroll compressor bodies disposed in the housing. A motor is disposed within the housing and operably connected to a drive shaft for driving one of the scroll compressor bodies. The drive shaft is rotationally supported at one end by a crankcase which includes a bearing housing and a bearing. The crankcase includes a plurality of openings or gas passages passing through the crankcase, as well as a plurality of generally cylindrical sections positioned respectively between adjacent openings. The cylindrical sections define contact regions which can engage an inner periphery of the housing when the crankcase is mounted therein.

A screw compressor 2 includes a compressor main body 4, a motor 8, and a gearbox 10. The compressor main body 4 includes screw rotors 5c, 5d, 6c, and 6d, rotor casings 5e and 6e accommodating therein the screw rotors 5c, 5d, 6c, and 6d, and main body casings 5a and 6a accommodating therein the rotor casings 5e and 6e, the main body casings being provided with first flanges 5b and 6b on respective ends thereof. The motor 8 drives the screw rotors 5c, 5d, 6c, and 6d via gears 10f and 10g. The gearbox 10 has an attachment surface Son which the first flange 6b to the main body casings 5a and 6a is attached, accommodates therein the gears 10f and 10g, and has a substantially rectangular shape. In a state where the compressor main body 4 is attached to the gearbox 10, a part of the first flange 6b extends to an outside of the attachment surface S, and projection regions of the rotor casings 5e and 6e onto the attachment surface S exist within the attachment surface S. In this way, vibrations of the screw compressor 2 can be reduced.

An apparatus for applying a vacuum during a surgical procedure can include a vacuum pump assembly having a port, a first housing, a second housing, a first silencer or tubular magnet and a second silencer. The first housing can define a first cavity receiving the vacuum pump assembly therein. A portion of the first housing can be formed by a portion of the port. The second housing can define a second cavity receiving the first housing therein. A portion of the second housing can be formed by a second portion of the port. The first silencer or tubular magnet can be coupled to the first housing and can have a longitudinal extent along a longitudinal axis. The first silencer or tubular magnet can extend from the first housing within the second cavity. The second silencer can be coupled to the second housing and can have a longitudinal extent along a longitudinal axis. The second silencer can extend from the second housing within second cavity.