A hermetic compressor according to the present disclosure may include an oil guide disposed on a rotating shaft between a driving motor and a main frame, the oil guide may include an oil block surrounding a main bearing surface between the main frame and the rotating shaft, and one end of the oil block may radially overlap a shaft support protrusion of the main frame. This can suppress oil returned after lubricating a compression unit from being scattered, thereby reducing a leakage of the oil to outside of a casing through a refrigerant discharge pipe.

A refrigerant compressor unit, including a compressor housing and at least one compressor element that is arranged in the compressor housing, is movable by bearing and drive parts, and operates in at least one compressor chamber, at least one lubricant supply point arranged in the compressor housing for at least one of the bearing and drive parts and/or compressor element, and a lubricant supply line to the at least one lubricant supply point, wherein the lubricant supply line has a lubricant storage chamber through which lubricant flows and in which a lubricant presence sensor is arranged for detecting the presence of lubricant in the lubricant storage chamber.

A twin-shaft pump comprising: a pumping chamber; two rotatable shafts each mounted on bearings is disclosed. Each of the two rotatable shafts comprises at least one rotor element, the rotor elements being within the pumping chamber and the two rotatable shafts extending beyond the pumping chamber to a support member. The support member comprises mounting means for mounting the bearings at a predetermined distance from each other, the predetermined distance defining a distance between the two shafts. A thermal break between the pumping chamber and the support member is provided for impeding thermal conductivity between the pumping chamber and the support member, such that the pumping chamber and support member can be maintained at different temperatures. The support member and the rotor elements are formed of different materials, a coefficient of thermal expansion of a material forming the support member being higher than a coefficient of thermal expansion of a material forming the rotor elements.

A twin-shaft pump comprising: a pumping chamber; two rotatable shafts each mounted on bearings is disclosed. Each of the two rotatable shafts comprises at least one rotor element, the rotor elements being within the pumping chamber and the two rotatable shafts extending beyond the pumping chamber to a support member. The support member comprises mounting means for mounting the bearings at a predetermined distance from each other, the predetermined distance defining a distance between the two shafts. A thermal break between the pumping chamber and the support member is provided for impeding thermal conductivity between the pumping chamber and the support member, such that the pumping chamber and support member can be maintained at different temperatures. The support member and the rotor elements are formed of different materials, a coefficient of thermal expansion of a material forming the support member being higher than a coefficient of thermal expansion of a material forming the rotor elements.

A compressor includes: a shell forming an outer portion thereof and having lower part in which an oil pan is formed to store oil; a motor provided in the shell; a compression unit provided in the shell to compress a working gas when being driven by the motor; a frame fixed to the shell and supporting the compression unit; a shaft supported by the frame, connecting the motor and the compression unit, provided to transmit a turning force of the motor to the compression unit, and including an oil passage; and an oil pump provided at lower part of the shaft to draw oil from the pan and supply the oil into the oil passage. The pump includes a bypass valve that is opened, when a pressure of oil flowing in the oil passage is higher than a threshold pressure, to return part of the oil to the pan.

The refrigerant compressor includes a compressor casing (2); an oil sump (13) arranged in the compressor casing (2); and an oil level sensor arrangement (14) configured to detect an oil level in the oil sump (13), the oil level sensor arrangement (14) including a tubular element (16) secured to the compressor casing (2) and a floating element (17) surrounding the tubular element (16) and being movably mounted with respect to the tubular element (16). The compressor casing (2) includes a passage opening (24) and dimensions of the tubular element (16), the floating element (17) and the passage opening (24) are defined to allow an insertion and a removal of the tubular element (16) and the floating element (17) into and out of the compressor casing (2) through the passage opening (24).

The refrigerant compressor includes a compressor casing (2); an oil sump (13) arranged in the compressor casing (2); and an oil level sensor arrangement (14) configured to detect an oil level in the oil sump (13), the oil level sensor arrangement (14) including a tubular element (16) secured to the compressor casing (2) and a floating element (17) surrounding the tubular element (16) and being movably mounted with respect to the tubular element (16). The compressor casing (2) includes a passage opening (24) and dimensions of the tubular element (16), the floating element (17) and the passage opening (24) are defined to allow an insertion and a removal of the tubular element (16) and the floating element (17) into and out of the compressor casing (2) through the passage opening (24).

Provided are a scroll compressor, a refrigeration device, and a vehicle. In the scroll compressor, an oil discharging hole of an oil separation structure and an oil storage tank are connected to each other by an oil outlet channel disposed in a housing, and an oil outlet of the oil outlet channel is located above an oil inlet. The oil outlet channel can guide a refrigeration oil discharged from the oil discharging hole to flow into the oil storage tank. After passing through the oil outlet channel, a flow rate and a pressure of the refrigeration oil decrease, and thus an impact of the refrigeration oil on the remaining refrigeration oil in the oil storage tank is reduced when discharged from the oil outlet. Therefore, the refrigeration oil within the oil storage tank remains stable and can always immerse an oil return hole of the oil storage tank.

A lubricating oil supply apparatus having a structure in which a valve is forced in a direction for opening a bypass hole by a centrifugal force, and a spring presses the valve in a direction in which the valve closes the bypass hole. When the above-described structure is applied to an oil pump in which an oil (lubricating oil) supply amount increases in proportion to an operation speed, it is possible to secure a sufficient oil (lubricating oil) supply amount in a low speed operation mode, and prevent oil from being supplied more than necessary in a high speed operation mode.

A screw compressor of the present invention comprises: a housing having a compression chamber; male and female rotors provided in the compression chamber; a driving shaft for rotating the male and female rotors; and a seal cover across which the driving shaft is provided, and further includes: an oil chamber provided at the seal cover, and returning, to the compression chamber, oil having leaked into the driving shaft; and a breather for injecting external air into the oil chamber. Therefore, the breather is provided at the upper part of the oil chamber and an oil recovery line is provided at the lower part thereof so as to cause a pressure difference between the upper and lower parts of the oil chamber, such that the flow of the oil having leaked into the driving shaft is smoothly recovered in the oil recovery line.