Oil-injected multistage compressor device including a low-pressure compressor element (2) with a gas inlet (4a) for gas to be compressed and a gas outlet (5a) for low-pressure compressed gas and a high-pressure stage compressor element (3) with a gas inlet (4b) for low-pressure compressed gas and a gas outlet (5b) for high-pressure compressed gas. The gas outlet (5a) of element (2) is connected to inlet (4b) of element (3) via a conduit (6). The conduit (6) has a regulatable intercooler (9) configured to regulate the temperature at the gas inlet (4b) of the high-pressure stage compressor element (3) so that it is above the dew point. The intercooler (9) includes a regulatable air cooler and/or a regulatable water cooler, and is configured to adjust the temperature of the air or water by using a bypass conduit (16) and/or by screening off part of the intercooler (9).

In a compressor compressing a refrigerant including hydrocarbon fluoride prone to disproportionate, provided, on a contact portion of the drive shaft and the bearing portion, is an elastic bearing portion as a heat generation suppression portion suppressing excessive heat generation due to line contact of an end edge portion of the bearing portion with the drive shaft during rotation of the drive shaft.

A compressor body includes a compression mechanism including a screw rotor that compresses gas, a casing that accommodates the compression mechanism and defines a compression working chambers therein, a suction side bearing that rotatably supports the screw rotor, a bearing chamber that accommodates the suction side bearing, and a liquid supply port that communicates with the compression working chambers and supplies liquid supplied from the outside of the casing into the compression working chambers. The casing has an internal liquid supply flow path that extends from a discharge side of the compression working chambers as an upstream side to a suction side of the compression working chambers as a downstream side and that supplies the liquid to the liquid supply port. The internal liquid supply flow path has a downstream portion reaching the bearing chamber and supplies the liquid to the suction side bearing.

A compressor includes a drive mechanism and a compression mechanism having a discharge passage and a plurality of members disposed to overlap. The discharge passage includes a muffling chamber, an inflow passage connected to an inflow end of the muffling chamber, and an outflow passage connected to an outflow end of the muffling chamber. The muffling chamber is formed across two or more of the plurality of members. The compression mechanism includes first and second cylinders, and a second closing member that covers an opening surface a of the first cylinder and an opening surface of the second cylinder. The muffling chamber includes an expansion chamber having a passage sectional area larger than the inflow and outflow passages. The expansion chamber is formed across the second closing member, and the first and second cylinders.

Machine provided with a machine element (2) and an oil pump (4) and a motor (3) to drive the machine element (2) and the oil pump (4), whereby the oil pump (4) is provided with a shaft (13) with a rotor (12), whereby the oil pump (4) is provided to pump oil from an oil reservoir (5) via an inlet channel (8) to nozzles that lead into the motor (3) and/or machine element (2) to lubricate and/or cool one or more bearings or other machine components, characterized in that in the inlet channel (8), near the oil pump (4) a dam (16) is provided that is higher than the height (A) of the central axis (18) of the shaft (13) of the oil pump (4) minus the smallest diameter (B) of the rotor (12) of the oil pump (4) divided by two.

Machine provided with a machine element (2) and an oil pump (4) and a motor (3) to drive the machine element (2) and the oil pump (4), whereby the oil pump (4) is provided with a shaft (13) with a rotor (12), whereby the oil pump (4) is provided to pump oil from an oil reservoir (5) via an inlet channel (8) to nozzles that lead into the motor (3) and/or machine element (2) to lubricate and/or cool one or more bearings or other machine components, characterized in that in the inlet channel (8), near the oil pump (4) a dam (16) is provided that is higher than the height (A) of the central axis (18) of the shaft (13) of the oil pump (4) minus the smallest diameter (B) of the rotor (12) of the oil pump (4) divided by two.

A scroll compressor includes a hermetic container, a fixed scroll, a swing scroll, a frame, an electric motor, and a shaft. A first groove and a second groove are provided outside a fixed wrap in a radial direction at an end plate surface of the fixed scroll. An oil supply hole for guiding lubricant oil from a through-hole opens at an end plate surface of the swing scroll. A single opening of the oil supply hole alternately communicates with the first groove and the second groove along with swing of the swing scroll.

A portable vacuum pump with a lubricating oil system having a quick oil change system. The oil change system includes at least two containers of oil and a switch mechanism operable to initially place the first container in fluid communication with the vacuum pump to serve as the primary oil reservoir while isolating the second container from such fluid communication. Then in a snap action, the switch mechanism can be flipped to place the second container with clean oil in fluid communication with the vacuum pump to serve as the primary oil reservoir and isolate the first container from fluid communication when its oil becomes dirty, all while the vacuum pump is still operating to evacuate an AC/R system. The first container can then be removed, refilled with clean oil, and returned in place and the switch mechanism flipped back to it when the second container of oil becomes dirty.

A portable vacuum pump with a lubricating oil system having a quick oil change system. The oil change system includes at least two containers of oil and a switch mechanism operable to initially place the first container in fluid communication with the vacuum pump to serve as the primary oil reservoir while isolating the second container from such fluid communication. Then in a snap action, the switch mechanism can be flipped to place the second container with clean oil in fluid communication with the vacuum pump to serve as the primary oil reservoir and isolate the first container from fluid communication when its oil becomes dirty, all while the vacuum pump is still operating to evacuate an AC/R system. The first container can then be removed, refilled with clean oil, and returned in place and the switch mechanism flipped back to it when the second container of oil becomes dirty.

Rotary positive displacement pump having a one-piece drive housing provided with an opening with a closing cover and with bearing seats engaging at least one bearing, wherein a primary drive shaft and a secondary drive shaft are each rotationally engaged to the bearings of the opposite bearing seats of their own axis, each drive shaft being provided with at least one gear which is interposed between the opposite bearing seats, and wherein each drive shaft engages a positive displacement screw rotor placed within a stator body, the positive displacement screw rotors being intended to enable the generation of a product flow between a product inlet duct and a product outlet duct with which the product section is provided, and wherein the gears are monolithic and at least one of the gears is keyed to the drive shaft by a keying device for hollow shafts.