The present invention includes: an electric component; a compression component driven by the electric component; and a sealed container accommodating the electric component and the compression component. The compression component includes: a shaft part rotated by the electric component; and a bearing part slidingly contacting the shaft part. A film having hardness equal to or more than hardness of a sliding surface of the bearing part is provided on a sliding surface of the shaft part. The sliding surface of the bearing part includes a curved-surface portion having an inner diameter that continuously increases, or the sliding surface of the shaft part includes a curved-surface portion having an outer diameter that continuously decreases.

The purpose of the present invention is to provide a reciprocating compressor which is a compact, light-weight, portable air compressor such that deterioration of performance due to problems such as wear on the surface finish of the cylinder when the compressor is used for a long period of time outside the operating temperature range thereof is prevented. To achieve this, the cylinder temperature is detected, and control is carried out so that the compressor is restarted at a lower restart pressure when the temperature is lower than a prescribed value and stopped (and also restarted, preferably) at a low pressure when the temperature is higher than a prescribed value.

A compressor that includes a casing, a compression mechanism provided inside the casing to compress a refrigerant, a rotary shaft transmitting a rotational force to the compression mechanism from a drive source provided outside the casing, a clutch connecting the drive source and the rotary shaft by a magnetic force generated when electric power is applied to the clutch and disconnecting the drive source and the rotary shaft by losing the magnetic force when the electric power applied thereto is cut off, and a rotation measurement means for receiving the magnetic force from the clutch to measure a change in magnetic flux according to the rotation of the rotary shaft and measure a rotational speed of the rotary shaft. Thus, it is possible to measure the rotational speed of the rotary shaft without including a permanent magnet.

A refrigeration apparatus includes a compressor connected to a refrigerant circuit, and a bearing monitor. The compressor includes a compression mechanism, an electric motor, a drive shaft, and a plain bearing that supports a journal portion of the drive shaft. The bearing monitor performs an abnormal-state operation to cope with poor lubrication on the plain bearing if an abnormal state condition is satisfied. The abnormal state condition is a condition indicating that a rate of change of current exceeds a first reference value. The rate of change of current is an amount of change in a driving current usable to drive the compressor per unit time. The journal portion of the drive shaft has a surface roughness of at least 0.05 μm.

A method of mounting a bearing to an air compressor including a shaft element having a first end defining a central cylindrical recess and a second is disclosed, which includes the steps of: fixing the second end of the shaft element to a center of a gear; inserting the first end of the shaft element through a central hole of a bearing to have an annular step of the shaft element abutted an inner ring of the bearing; and hitting the first end of the shaft element by a striking tool with a central pin to form an outwardly extending rim on the first end of the shaft element. With the method, the bearing can be firmly fixed between the outwardly extending rim and the annular step of the shaft element.

A compressor for a compressed-air feed of a compressed-air supply installation, for operating a pneumatic installation, includes: a first compression space; a second compression space; an air feed port; a compressed-air outlet; and a piston having a first face side, which is subjectable to pressure and which is directed toward the first compression space, and a second face side, situated opposite the first face side, which is subjectable to pressure and which is directed toward the second compression space, the first compression space being delimited by the first face side and the second compression space being delimited by the second face side. The first face side includes a full side and the second face side includes a step side. The piston is attached via a connecting rod to a drive. The first compression space and the second compression space are connected to one another via a connecting line.

A compressor includes a casing and a metallic coating. The casing includes a low-pressure casing part covering a low-pressure space and a high-pressure casing part covering a high-pressure space. The metallic coating is formed at least on a part of an outer surface of the casing. The metallic coating includes a low-pressure part coating formed in the low-pressure casing part, a high-pressure part coating formed in the high-pressure casing part, and a welded part coating formed in a welded part. At least either the average thickness of the low-pressure part coating or the average thickness of the welded part coating is greater than the average thickness of the high-pressure part coating.

A method of mounting a bearing to an air compressor including a shaft element having a first end and a second is disclosed, which includes the steps of: fixing the second end of the shaft element to a center of a gear; inserting the first end of the shaft element through a central hole of a bearing to have an annular step of the shaft element abutted an inner ring of the bearing; and hitting the first end of the shaft element by a striking tool to form an expanded or flared edge on a top face of the first end of the shaft element. With the method, the bearing can be firmly fixed between the expanded or flared edge and the annular step of the shaft element.

A hermetic compressor may include a crankshaft having an input shaft rotatably supported on the cast-iron block along the crankshaft axis and connected to the electric motor rotary output, and an eccentric crankpin orbitally rotating about the axis as the crankshaft is rotated. A pair of opposed pistons may lie on the common plane. Each piston may be pivotably connected to one of the connecting rod piston ends to drive the pistons in an oscillatory manner within the cylinders as the crankshaft rotates. The piston and cylinder pairs may cause fluid to be pumped from the inlet port to the outlet port as the piston oscillates varying the volume of the enclosed space bound by the piston and the cylinder pairs.

An air thermal conditioning system, for at least one of heating air and cooling air, which includes a cross-flow heat exchanger array. The cross-flow heat exchanger array includes a plurality of planar membrane heat exchangers disposed in parallel with a space separating adjacent planar membrane heat exchangers. Each of the planar membrane heat exchangers include a first sheet; a second sheet coupled to the first sheet; and at least one fluid chamber defined by the first and second sheets, with the at least one fluid chamber extending between first and second ends of the planar membrane heat exchangers and opening to a first and second port at the first and second ends respectively.