An engine comprises a housing and a combustion assembly carried by the housing. The combustion assembly comprises an annular bore defined by the housing, at least one combustion piston disposed within the annular bore, and a sealing mechanism configured to selectively seal the at least one combustion piston relative to at least one corresponding wall of the annular bore. The engine comprises at least one rotary valve configured to move between a first position within the annular bore to allow the at least one combustion piston to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one rotary valve and a second position within the annular bore to define a combustion chamber relative to the at least one combustion piston at the second location.

A rotary compressor is disclosed. The rotary compressor includes a sidewall path formed in an inner wall of a cylinder facing a vane slot and configured to form a space facing a side surface of a vane, and the vane is provided with a communication part configured to selectively communicate between the outside of the vane slot and the sidewall path according to a position of the vane.

A rotary compressor is disclosed. The rotary compressor includes a sidewall path formed in an inner wall of a cylinder facing a vane slot and configured to form a space facing a side surface of a vane, and the vane is provided with a communication part configured to selectively communicate between the outside of the vane slot and the sidewall path according to a position of the vane.

A rotary compressor may include a rotary shaft; a plurality of plates that supports the rotary shaft; a cylinder provided between the plurality of plates to define a compression space, and provided with a vane slot; a roller slidably coupled to the rotary shaft inside of the cylinder, and having a hinge groove on an outer circumferential surface thereof; and a vane, a first end of which is slidably coupled to the vane slot of the cylinder, and a second end of which is rotatably coupled to the hinge groove of the roller. At least one of first and second axial end surfaces of the roller facing the plurality of plates is provided with a dimple portion having a predetermined depth. With this structure, contact surfaces between the roller and the plate may be prevented from being in close contact with each other.

A rotary compressor may include a rotary shaft; a plurality of plates that supports the rotary shaft; a cylinder provided between the plurality of plates to define a compression space, and provided with a vane slot; a roller slidably coupled to the rotary shaft inside of the cylinder, and having a hinge groove on an outer circumferential surface thereof; and a vane, a first end of which is slidably coupled to the vane slot of the cylinder, and a second end of which is rotatably coupled to the hinge groove of the roller. At least one of first and second axial end surfaces of the roller facing the plurality of plates is provided with a dimple portion having a predetermined depth. With this structure, contact surfaces between the roller and the plate may be prevented from being in close contact with each other.

A pump body assembly, a compressor and an air conditioner are provided. The pump body assembly has a crankshaft, a main bearing, and a cylinder body. The crankshaft has a main shaft part and an eccentric part connected with the main shaft part. The main bearing has a hub part. The main shaft part extends through a through hole in the hub part. A first oil guide groove is formed in the hole wall of the through hole. A sliding vane slot and a center hole are formed in the cylinder body. The crankshaft extends through the center hole. The main bearing is located at the one side of the cylinder body. The crankshaft and the main bearing are in uniform contact with oil films at all positions. The abnormal wear of the main shaft part of the crankshaft can be reduced, and the service life of the compressor can be prolonged.

A pump body assembly, a compressor and an air conditioner are provided. The pump body assembly has a crankshaft, a main bearing, and a cylinder body. The crankshaft has a main shaft part and an eccentric part connected with the main shaft part. The main bearing has a hub part. The main shaft part extends through a through hole in the hub part. A first oil guide groove is formed in the hole wall of the through hole. A sliding vane slot and a center hole are formed in the cylinder body. The crankshaft extends through the center hole. The main bearing is located at the one side of the cylinder body. The crankshaft and the main bearing are in uniform contact with oil films at all positions. The abnormal wear of the main shaft part of the crankshaft can be reduced, and the service life of the compressor can be prolonged.

A lower end plate includes: bolt holes through which bolts penetrate; a lower discharge valve; a lower discharge-valve accommodating recessed portion into which the lower discharge valve is accommodated; and a lower discharge-chamber recessed portion. A lower end plate cover is provided with a bulging portion. A lower end-plate cover chamber is formed by the lower discharge-valve accommodating recessed portion, the lower discharge-chamber recessed portion, and the bulging portion. Refrigerant passage holes include main refrigerant passage holes provided on the lower discharge-chamber recessed portion, and sub-refrigerant passage holes provided between the bolt hole and the lower discharge-valve accommodating recessed portion away from the lower discharge-valve accommodating recessed portion. The bulging portion is, in a cross section orthogonal to a rotating shaft, formed so as to overlap with at least a part of each of the main refrigerant passage holes and the sub-refrigerant passage holes.

A pump body assembly, a compressor and an air conditioner are provided. The pump body assembly has a crankshaft, a main bearing, and a cylinder body. The crankshaft has a main shaft part and an eccentric part connected with the main shaft part. The main bearing has a hub part. The main shaft part extends through a through hole in the hub part. A first oil guide groove is formed in the hole wall of the through hole. A sliding vane slot and a center hole are formed in the cylinder body. The crankshaft extends through the center hole. The main bearing is located at the one side of the cylinder body. The crankshaft and the main bearing are in uniform contact with oil films at all positions. The abnormal wear of the main shaft part of the crankshaft can be reduced, and the service life of the compressor can be prolonged.

A rotary compressor includes at least one cylinder in which a discharge guide groove is disposed at one side of a vane slot; a roller orbitably provided in the cylinder, and disposed with a hinge groove on an outer circumferential surface thereof; a vane in which one end portion thereof is rotatably inserted into the hinge groove of the roller, and the other end portion thereof is slidably inserted into the vane slot of the cylinder; and a plurality of bearing plates that seals both side surfaces of the cylinder, and at least one side of which is disposed with a discharge port to communicate with the discharge guide groove. The discharge port communicates with a refrigerant residual space defined between the vane slot and the discharge guide groove. Refrigerant in the refrigerant residual space may be discharged even after the roller passes through the discharge guide groove.