Abstract: A variable capacity rotary compressor includes a housing having a cylindrical compressing chamber defined therein, a rotating shaft having an eccentric body part which rotates in the compressing chamber, a ring piston fitted over the eccentric body part of the rotating shaft so as to have the ring piston rotate while being in contact with an inner surface of the compressing chamber, a vane mounted in the housing so as to have the vane advance or retract in a radial direction of the compressing chamber in accordance with a rotation of the ring piston, and a control unit which is connected to the vane and moves in opposite directions in response to pressures of a refrigerant inlet and a refrigerant outlet of the compressor, so as to control a moving range of the vane. Accordingly, a simpler construction of the compressor is achieved and a refrigerant compressing capacity is easily controlled.

Abstract: A compressor comprising a hermetic casing, a cylinder assembly disposed in the casing, a Z-plate disposed in the cylinder assembly for dividing an inner space of the cylinder assembly into a plurality of compression spaces, and sucking, compressing and discharging a fluid while being rotated by a driving unit, and vanes being contacted with both sides of the Z-plate to make a reciprocal movement, wherein the cylinder assembly includes a vane slot for inserting the vane, said vane slot having an opened portion opened towards an outer circumference of the cylinder assembly, thereby facilitating a processing of the vane slot, enhancing productivity of the cylinder assembly and reducing a production cost.

Abstract: An object of the present invention is to provide a multi-cylinder rotary compressor which can enhance the reliability by improving the compression efficiency/mechanical efficiency. The bearings are fixed on the inner wall of the closed container, the cylinders are fixed to the bearings, and a gap is formed between the respective cylinders and the inner wall of the closed container. The design with the relatively large internal volume of the closed container is possible, and the reliability can be enhanced. Further, improvement in the compression efficiency and the mechanical efficiency can be achieved with the compact multi-cylinder rotary compression element.

Abstract: A hermetic compressor assembly including a compressor housing, a compression mechanism disposed in the housing, a motor disposed in the housing; and a crankshaft operatively coupling the compression mechanism and the motor and having an axis of rotation. The crankshaft includes a cylindrical eccentric and a counter eccentric lobe. The cylindrical eccentric has a central axis, defines a circular axial profile, and is located on one radial side of the axis of rotation. The counter eccentric lobe is integrally formed with the crankshaft on the opposite side of the crankshaft from the eccentric, is axially adjacent the eccentric, and is located within the circular axial profile.

Abstract: The present invention provides a hermetic or open compressor for hydrocarbon refrigerant having high reliability. According to the present invention, in the compressor using hydrocarbon as refrigerant, synthetic oil such as polyalkylene glycol oil, ester oil or ether oil is used as freezer oil. Sliding member of the compressor includes both a portion made of aluminum material and a portion made of iron material. Therefore, it is possible to realize a compressor having excellent wear resistance and high reliability.

Abstract: A compressor includes a particularly shaped discharge valve which extends into the discharge port. The shaped valve includes a convex portion on the seat side of the valve which extends downwardly into the discharge port. The shaped valve furthermore includes a concave portion on the seat side of the valve that begins where the convex portion ends. The beginning of the concave portion on the seat side of the valve is located so as to prevent flow separation of the refrigerant when flowing along the convex portion of the valve as it leaves the compression chamber of the compressor.

Abstract: There is provided a highly reliable rotary compressor which uses polyalkylene glycol as a lubricant or polyalfa olefin as base oil in a compressor utilizing as a refrigerant carbon dioxide which is a natural refrigerant, and prevents abnormal abrasion of a roller and a vane.

Abstract: A compressor includes a particularly shaped discharge valve which extends into the discharge port. The shaped valve includes a convex portion on the seat side of the valve which extends downwardly into the discharge port. The shaped valve furthermore includes a concave portion on the seat side of the valve that begins where the convex portion ends. The beginning of the concave portion on the seat side of the valve is located so as to prevent flow separation of the refrigerant when flowing along the convex portion of the valve as it leaves the compression chamber of the compressor.

Abstract: A discharge valve is provided for implementation between a discharge pressure zone and a discharge chamber. The discharge valve is operable between an open position for enabling fluid flow between the discharge pressure zone and the discharge chamber and a closed position for prohibiting fluid flow between the discharge pressure zone and the discharge chamber. The discharge valve includes a housing defining a cavity and having a flow aperture therethrough. A valve disc is slidably disposed within the housing and is operable for defining the open and closed positions of the discharge valve. The valve disc includes a contoured body for reducing stresses experienced within the valve disc and improving fluid flow therearound.

Abstract: A rotating type machine including a first moving member having a first surface and a second member having a second surface slidably interfacing with the first surface. The first and second surfaces have relative movement therebetween, and one of the first and second members is supported by the other member through the interface of their respective first and second surfaces. At least one of the first and second surfaces is provided with at least one recess therein. A liquid lubricant is provided between the first and second surfaces, and the lubricant is received in the recess. Relative to the surface in which the recess is provided, the recess has a maximum depth which ranges between about 0.00125 and 0.0060 inches, and a surface area which ranges between about 1.767×10−4 and 1.

Abstract: A discharge valve is provided for implementation between a discharge pressure zone and a discharge chamber. The discharge valve is operable between an open position for enabling fluid flow between the discharge pressure zone and the discharge chamber and a closed position for prohibiting fluid flow between the discharge pressure zone and the discharge chamber. The discharge valve includes a housing defining a cavity and having a flow aperture therethrough. A valve disc is slidably disposed within the housing and is operable for defining the open and closed positions of the discharge valve. The valve disc includes a contoured body for reducing stresses experienced within the valve disc and improving fluid flow therearound.

Abstract: An object of the present invention is to provide a multi-cylinder rotary compressor which can enhance the reliability by improving the compression efficiency/mechanical efficiency. The bearings are fixed on the inner wall of the closed container, the cylinders are fixed to the bearings, and a gap is formed between the respective cylinders and the inner wall of the closed container. The design with the relatively large internal volume of the closed container is possible, and the reliability can be enhanced. Further, improvement in the compression efficiency and the mechanical efficiency can be achieved with the compact multi-cylinder rotary compression element.

Abstract: The invention discloses a rotary piston pump, which comprise a cylinder block, a front end cover and a rear end cover secured to the front and the rear end surfaces of the cylinder block respectively; a cam rotor being fitted in the chamber of the cylinder block, the portion of the rotor having the maximum radius comes into sliding contact with the inner wall of the cylinder block so as to form an axially extending sealing region; a shaft, the rotor is mounted on the shaft and rotatable therewith; a separating means for separating the axially extending sealed chamber, which is formed between the outer surface of rotor and the inner wall of the cylinder block, into an induction chamber and an exhaustion chamber; an inlet and an outlet respectively provided at the two sides of the separating means and communicated with the induction chamber and the exhaustion chamber, the separating means comprises: an axially extending circular arc-shaped recess formed in the inner wall of the cylinder block with its axis bein

Abstract: There is provided a highly reliable rotary compressor which uses polyalkylene glycol as a lubricant or polyalfa olefin as base oil in a compressor utilizing as a refrigerant carbon dioxide which is a natural refrigerant, and prevents abnormal abrasion of a roller and a vane.

Abstract: The present invention provides a hermetic or open compressor for hydrocarbon refrigerant having high reliability. According to the present invention, in the compressor using hydrocarbon as refrigerant, synthetic oil such as polyalkylene glycol oil, ester oil or ether oil is used as freezer oil. Sliding member of the compressor includes both a portion made of aluminum material and a portion made of iron material. Therefore, it is possible to realize a compressor having excellent wear resistance and high reliability.

Abstract: A rotary compressor of the present invention includes a compression mechanism, motor and hermetically sealed housing. The compression mechanism includes compression elements, a rotary shaft and bearing. The compression elements includes a cylinder block, piston, and vane. The cylinder block has a cylinder hole and vane groove. The compression mechanism and the motor are housed in the hermetically sealed housing. The cylinder block is made up of sintered metal. The compression mechanism is welded to the hermetically sealed housing in a region other than the cylinder block. Preferably, the cylinder block includes a first cylinder block and a second cylinder block, and the first cylinder block and the second cylinder block are formed by machining sinter-molded blanks identical in shape. With this configuration, it is possible to reduce the machining processes and to make the blank parts usable in common, thereby realizing a low-cost compressor.

Abstract: A rotary compressor uses a freon without containing chlorine ions and uses polyol ester as a lubricant or plyvinyl ether as a base oil for providing a highly reliable rotary compressor, and for preventing abnormal abrasion. The rotary compressor has a roller and a vane sliding contact with an outer cirumference of the roller. A sliding contact portion between the vane and the roller is formed with a radius of curvature Rv, and satisfies T<Rv<Rr, wherein T is the thickness of the vane and Rr is the radius of curvature of the outer circumference of the roller.

Abstract: A rotary compressor comprises a cylinder having an inner space and a groove, a roller sliding along the inside of the inner space of the cylinder, a vane penetrating through the groove, and refrigerant. The groove penetrates through the outside and inner space of the cylinder. The vane slides on the roller, and the vane also slides in and out of the groove. The vane includes stainless steel formed by sintering of powder material, a nitrogen diffusion layer disposed on the surface of the stainless steel, and a compound layer of iron and nitrogen disposed on the surface of the nitrogen diffusion layer. The stainless steel has a plurality of fine pores formed by sintering of powder material. The plurality of fine pores have a porosity of 15% or less.

Abstract: A rotating type machine including a first moving member having a first surface and a second member having a second surface slidably interfacing with the first surface. The first and second surfaces have relative movement therebetween, and one of the first and second members is supported by the other member through the interface of their respective first and second surfaces. At least one of the first and second surfaces is provided with at least one recess therein. A liquid lubricant is provided between the first and second surfaces, and the lubricant is received in the recess. Relative to the surface in which the recess is provided, the recess has a maximum depth which ranges between about 0.00125 and 0.0060 inches, and a surface area which ranges between about 1.767×10−4 and 1.

Abstract: A rotary compressor of the low operational noise type is disclosed. This compressor consists of a casing, a rotating shaft set within the casing, a roller eccentrically fixed to the rotating shaft and eccentrically, rotatably set within a cylinder so as to form a variable suction chamber and a variable compression chamber within the cylinder. The compressor also has a bypass passage, which is formed on the internal surface of the cylinder at a position around the refrigerant exhaust stroke initiating point, thus allowing the compression and exhaust chambers to communicate with each other through the bypass passage and allowing highly compressed refrigerant to be fed from the compression chamber back into the suction chamber at the initial stage of each exhaust stroke.

Abstract: An object of the present invention is to provide a multi-cylinder rotary compressor which can enhance the reliability by improving the compression efficiency/mechanical efficiency. The bearings are fixed on the inner wall of the closed container, the cylinders are fixed to the bearings, and a gap is formed between the respective cylinders and the inner wall of the closed container. The design with the relatively large internal volume of the closed container is possible, and the reliability can be enhanced. Further, improvement in the compression efficiency and the mechanical efficiency can be achieved with the compact multi-cylinder rotary compression element.

Abstract: A rotary compressor uses a freon without containing chlorine ions and uses polyol ester as a lubricant or plyvinyl ether as a base oil for providing a highly reliable rotary compressor, and for preventing abnormal abrasion. The rotary compressor has a roller and a vane sliding contact with an outer circumference of the roller. A sliding contact portion between the vane and the roller is formed with a curvature Rv, and satisfies T<Rv<Rr, wherein T is the thickness of the vane and Rr is the curvature of the outer circumference of the roller.

Abstract: The present invention provides a hermetic or open compressor for hydrocarbon refrigerant having high reliability. According to the present invention, in the compressor using hydrocarbon as refrigerant, synthetic oil such as polyalkylene glycol oil, ester oil or ether oil is used as freezer oil. Sliding member of the compressor includes both a portion made of aluminum material and a portion made of iron material. Therefore, it is possible to realize a compressor having excellent wear resistance and high reliability.

Abstract: A member is disclosed which includes a hard carbon film provided through an interlayer or directly on a main body such as a vane. A mixed layer is formed within the main body or interlayer adjacent to an outer surface of the main body or interlayer. The mixed layer contains carbon and a constituent element of either the main body or the interlayer. The mixed layer has a carbon content gradient in its thickness direction so that a carbon content in a thickness portion thereof closer to an outer surface of the mixed layer is higher than in a thickness portion thereof remoter from the outer surface of the mixed layer.

Abstract: When sliding elements, slide bushings, vanes and Oldham rings employed in various types of refrigeration compressors and other applications meet the following conditions, they resist sticking to aluminum-base components, resist depletion of the oil film on slide faces, and exhibit excellent wear resistance. Firstly, the elements must comprise an iron-base sinter having closed cells on at least the slide face. Secondly, in order for the oil film to be maintained on the slide face by the closed cells and to enhance lubricating properties, the proportion of closed cells having circular-equivalent diameter of 10 &mgr;m or less, i.e. the number of ≦10 &mgr;m cells/total number of cells, must equal 85% or more, and the opening area of the closed cells on the slide face must equal 5% or less. Finally, the sliding element density must be 7.3 g/cm3 or higher.

Abstract: A hermetic rotary compressor comprising a housing, a cylinder block and a bearing assembly in the housing and defining a cylindrical cavity therein. A roller piston, drivingly coupled to a motor, is disposed in the cylindrical cavity. The cylinder block includes a reciprocating vane within a vane slot defined therein. The vane slot extends axially through said cylinder block, radially from an outside perimeter surface of the cylinder block to the cylindrical cavity. At least a portion of the vane slot is defined by a pair of substantially parallel sidewalls with the vane disposed in the vane slot and urged against the roller piston. The vane is guided by the substantially parallel sidewalls and a clearance exists between the vane and the substantially parallel sidewalls.

Abstract: Rotary compressor including a main bearing having a discharge passage for discharging compressed gas and a boss for inserting a motor shaft, the main bearing forming a component of a compression chamber, and a muffler having a boss hole for passing the boss of the main bearing and a discharge opening for discharging the compressed gas, the muffler mounted on the main bearing, wherein the discharge opening in the muffler is formed at least one in number inside of the discharge passage in the main bearing, whereby attenuating a noise generated in operation of the rotary compressor, effectively.

Abstract: An object of the present invention is to provide a multi-cylinder rotary compressor which can eliminate a number of balancers for preventing vibrations. Assuming that the mass eccentricity in a cylinder is m1×r1; the mass eccentricity in another cylinder is m2×r2; the mass eccentricity of a balancer attached to the lower side of a rotator is m3×r3; the mass eccentricity of another balancer attached to the upper side of the rotator is m4×r4; respective distances from the cylinder to another cylinder, the lower balancer and another balancer are L2, L3 and L4, when the balancing is attained with the expressions m1×r1+m4×r4=m2×r2+m3×r3, m4×r4×L4=m2×r2×L2+m3×r3×L3, and m1×r1=m2×r2, the lower balancer is eliminated and the mass eccentricity of the balancer is set to be not less than 20% and not more than 80% of m4×r4.

Abstract: A rotary compressor is provided with a cylinder which defines a cylinder chamber and a piston disposed in the cylinder chamber. The piston includes a roller which performs a revolving motion within the cylinder chamber and a vane which partitions the interior of the cylinder chamber into a suction chamber and a compression chamber. A small space is provided so as to communicate with the compression chamber in only a predetermined section without communicating with the suction chamber so as to suppress noise generated by a pressure fluctuation in the interior of a compression chamber and, at the same time, can prevent the occurrence of a loss induced by re-expansion of a refrigerant remaining in a small space and a loss induced by return of the refrigerant to a suction chamber.

Abstract: In an H/A range in which the ratio H/A≧0.07, where H is the thickness of the bottom wall of a recess (8) provided with a discharge port (4) and a valve seat (9) and formed in the flange (5) of a bearing member (3,3′) and A is the width of the recess (8), the smaller the ratio H/A, the greater is the coefficient of performance (COP). In an H/A range in which H/A<0.07, the COP decreases due to the leakage of the refrigerant resulting from the deflection of the bottom wall of the recess (8) and, eventually, the bearing members (3,3′) are broken. The discharge port (4), the recess (8) and the valve seat (9) are formed so that the ratio H/A≧0.07 and the ratio T/B≦0.3, where T is the thickness of the valve seat (9) and B is the diameter of the discharge port (4). The valve seat (9) can be formed in the thickness T smaller than that of the valve seat of an equivalent conventional compressor, suppressing the deflection of the bottom wall of the recess (8).

Abstract: A rotary compressor includes a cylinder having a slot, an eccentric shaft disposed in the cylinder, a roller formed around the shaft, a vane inserted into the slot and having grooves on its surface, and a sealing material inserted into the grooves. The sealing material prevents leakage and influx of gas through a gap between the cylinder and the vane, improving the efficiency of a rotary compressor.

Abstract: A hermetic rotary compressor comprising a housing, a cylinder block and a bearing assembly in the housing and defining a cylindrical cavity therein. A roller piston, drivingly coupled to a motor, is disposed in the cylindrical cavity. The cylinder block includes a reciprocating vane within a vane slot defined therein. The vane slot extends axially through said cylinder block, radially from an outside perimeter surface of the cylinder block to the cylindrical cavity. At least a portion of the vane slot is defined by a pair of substantially parallel sidewalls with the vane disposed in the vane slot and urged against the roller piston. The vane is guided by the substantially parallel sidewalls and a clearance exists between the vane and the substantially parallel sidewalls.

Abstract: The present invention relates to a hermetic rotary compressor. More particularly, since the conventional rotary compressor has problems that the effect of a surge recess for reducing noises due to pressure pulsation is insufficient, and it is impossible to obtain the maximum compression efficiency, the present invention is constructed such that noises due to pressure pulsation can be reduced to the maximum and at the same time the compressive driving force required for compressing gaseous refrigerant is decreased to thereby improve the compression efficiency.

Abstract: A scroll fluid machine having a lubrication pump provided between sliding contact surfaces of an orbiting scroll member and a thrust bearing in a casing. The pump has an orbiting member accommodating recess provided in the sliding contact surface of the thrust bearing. An orbiting member projects from the sliding contact surface of the orbiting scroll member into the recess. A slide plate defines a suction chamber and a discharge chamber in the recess. As the orbiting scroll member orbits, the orbiting member orbits in the recess, causing a lubricant contained in the casing to be sucked from a suction passage and delivered to the inside of a boss portion accommodating an orbiting bearing.

Abstract: A hermetic rotary compressor assembly having a housing, a cylinder block and a bearing assembly within the housing. The cylinder block and the bearing assembly define a cylindrical cavity which has a roller piston disposed therein. The rotary compressor assembly includes a motor drivingly coupled to the roller piston and the cylinder block has a vane slot extending completely axially through and extending radially from an outside perimeter surface of the cylinder block to the cylindrical cavity. At least a portion of the vane slot is defined by a pair of substantially parallel sidewalls and a vane is disposed in and guided by the vane slot and is urged against said roller piston. The cylinder block is fixed in a state of circumferentially oriented stress.

Abstract: The invention concerns an oil-sealed vane-type rotary vacuum pump (1) with a rotor (3) and an oil pump (45, 46) whose suction chamber is fitted with feeds (64, 65) for gas and oil. In order to simplify the supply of a gas/oil mixture to the vacuum pump, the invention proposes that the gas and oil feeds (64, 65) are disposed in such a way that initially only oil and subsequently both oil and air are aspirated into the volume swept by the oil pump (45, 46) as it rotates.

Abstract: A vane of a compressor is made of solid phase sintering material of which a sintering density is not less than 7.2g/cm.sup.3 and a hollow rate is not more than 10%, and to which CrN phase is adhered through a PVD process. A roller of the compressor is made of hardened and tempered material having a hardness equal to cast iron FC300 (specified by JIS). The roller may be made of hardened and tempered material including at least one of Ni, Cr and Mo, and having a hardness equal to cast iron FC300. The vane and roller are combined, so that a sliding section having excellent abrasion-resistance can be constructed. As a result, a rotary compressor, which employs R134a or R22 coolant as well as HFC system or HC system coolant both of which are R22 substitutes, having extremely high reliability can be realized.

Abstract: The present invention is to provide a refrigerant compressor comprising a compressing element driven by a rotary shaft, for compressing and discharging a sucked HFC type refrigerant or refrigerant mainly comprising the HFC type refrigerant by the compressing element, where a rotary shaft applied with the plasma sulphonitriding treatment on the surface is used as the rotary shaft. Or a vane applied with the plasma sulphonitriding treatment on the surface of a vane made of a steel equivalent to a high speed tool steel vane or a steel equivalent to a stainless steel is used. Accordingly, a refrigerant compressor comprising a rotary shaft or a vane having a low friction coefficient in a sliding portion on the surface of the rotary shaft or the vane and a high wear resistance can be provided even in the case an ester type refrigerator oil or an ether type refrigerator oil is used as the refrigerator oil and an HFC type refrigerant is used.

Abstract: A compressor includes a normally open discharge valve assembly for controlling compressed refrigerant flow from the discharge chamber through the compression members. This controlling of flow results in an increased performance for the compressor by reducing recompression volume and the elimination of reverse rotation at shut down. The discharge valve assembly includes a valve seat, a valve plate and a valve stop secured within a recess formed within the compressor. The valve stop and the valve seat include a contoured surface which is engaged by the valve plate when it opens and closes. The contoured surface control the movement of the valve plate.

Abstract: A compressor comprises a cylinder assembly forming a compression space. A compressing member is movable disposed in the compression space for compressing fluid therein. A discharge port communicates with the compression space for discharging compressed fluid. A valve is mounted on the cylinder assembly for sliding movement across the discharge port between a first position blocking the discharge port, and a second position unblocking the discharge port. A valve mover in the form of a plate spring is connected to the valve and communicates with pressure in the compression space. In response to a pressure build-up in the compression space, the plate spring is elastically deformed to slide the valve from the first position to the second position for unblocking the discharge port.

Abstract: A pump for moving a fluid has a housing with a cylindrical internal chamber accommodating a cylindrical piston. The piston is eccentrically secured to a shaft rotatably mounted on the housing. A baffle located in a recess in the housing controls the flow of fluid through the housing from a fluid inlet passage to a fluid outlet passage. A pair of cams eccentrically mounted on the shaft linearly move cam followers connected to the baffle to maintain an end of the baffle in close relation to the piston as the piston turns in the chamber.

Abstract: A slit, spanning a distance across the top of the vane slot in a cylinder for a rolling piston compressor, safely distributes the stress which occurs in the vane slot. The slit opens onto the bore, in the cylinder, which is provided for a rotary shaft and rotary piston, and onto the vane slot.

Abstract: A member is disclosed which includes a hard carbon film provided through an interlayer or directly on a main body such as a vane. A mixed layer is formed within the main body or interlayer adjacent to an outer surface of the main body or interlayer. The mixed layer contains carbon and a constituent element of either the main body or the interlayer. The mixed layer has a carbon content gradient in its thickness direction so that a carbon content in a thickness portion thereof closer to an outer surface of the mixed layer is higher than in a thickness portion thereof remoter from the outer surface of the mixed layer.

Abstract: Vane for use in a rotary vane compressor or other rotary expansible chamber device and process for making the vane in which the vane comprises a vane body having a first tip, a second tip, and a vane body interconnecting the tips. At least one of the first and second tips comprises a metal alloy and a lubricating agent provided in admixture with the metal alloy. The vane body comprises a metal alloy and a plurality of inorganic particles provided in admixture with the metal alloy. The inorganic particles have a coefficient of thermal expansion which is less than the coefficient of thermal expansion of the metal alloy.

Abstract: A notch is provided in the motor end bearing of a rotary compressor in the region of the discharge port. The notch enhances the flow by smoothing the flow path and guiding the flow so as to impinge upon the discharge valve in a glancing manner and reduces the noise from the valve and valve stop and from the turbulent flow through the discharge port. The notch is located along the axis of the discharge valve and on the side of the valve port on which the valve is pivoted.

Abstract: An oil groove is formed in the shaft journal facing the upper bearing land of a high side rotary compressor and is located relative to the eccentric such that the groove is not located in a high loading region of the shaft journal.

Abstract: A tip of a vane slid with a rolling piston is mechanically finish-ground in the direction of the sliding movement between the vane and the rolling piston, and provided with a protective coating film being proof against abrasion which is composed of non-ferrous metal formed by a physical vapor deposition method, or composed of a chromium nitride compound formed by an ion plating method. Hydrofluorocarbon is employed as a refrigerant, and ester oil being compatible with the refrigerant is used as a lubricating oil.

Abstract: Lubrication deficiencies related to the use of lubricants in HFC refrigeration compressors can be mitigated by providing a diamond-like-carbon coating on a member subject to wear due to lubrication deficiencies. Specifically, the tip of the vane of a rotary compressor is coated with a diamond-like-carbon coating made up of alternating layers of tungsten carbide and a lubricious material 0.5 to 5.0 microns thick.

Abstract: A closed-type transmission compressor comprises an upper shell having a compressing unit and a lower shell having a transmission unit. The transmission unit includes a stator which generates magnetic power, a rotor rotated by the magnetic power of the stator, and a crankshaft rotated by rotation of the rotor. The compressing unit includes a slider changing rotatory movement of the crankshaft into linear movement, a piston attached to the slider and reciprocating in a cylinder, a head cover covering the cylinder, an inlet valve between a head and a head cover which permits intake of a refrigerant gas, an outlet valve between the head and the head cover which permits exhaust of the refrigerant gas, a propeller conveying oil in the lower shell into the crankshaft, and a screw-shaped oil path groove formed in the inside of crankshaft along which the oil is flowed.

Abstract: In a hermetic type compressor, a sliding part (11) between a main shaft (4) and a lower end plate (8) is large in wear, and it is not allowed to operate stably for a long period. By communicating between the sliding part (11) and an oil feed pump (9) through an oil feed port (12), refrigerating machine oil (2) is supplied by force into the sliding part (11), and hence the lubrication is improved and the reliability is enhanced. In particular, it is preferably applied to the hermetic type compressor using HFC derivative refrigerants.