Crankshaft for rotatory compressor, rotatory compressor and refrigerating cycle device

Abstract

A crankshaft for a rotary compressor includes: a body ( 1 ) and an eccentric portion ( 2 ), the eccentric portion ( 2 ) being fitted over the body ( 1 ), wherein at least one of a flexible structure ( 21 ) and an oil pressure surface ( 22 ) is arranged on the eccentric portion ( 2 ). The flexible structure ( 21 ) is configured to deform inwards when subject to an external force in an inward direction. The oil pressure surface ( 22 ) is configured in such a way that in a direction opposite to a rotating direction of a rotating central axis of a crankshaft ( 300 ), a distance between a front end ( 221 ) of the oil pressure surface ( 22 ) and the central axis of the eccentric portion ( 2 ) is smaller than a distance between a tail end ( 222 ) of the oil pressure surface ( 22 ) and the central axis of the eccentric portion ( 2 ). Also disclosed are a rotary compressor and a refrigerating cycle device. The crankshaft can effectively solve the problem that a rotary compressor gets stuck due to abnormal contact between a piston and an air cylinder, and a high-pressure oil wedge can be formed at a tail portion of an oil cavity, thereby increasing an inlet oil pressure, and improving the environment of lubrication between an eccentric portion and a piston.

1 . A crankshaft for a rotary compressor, comprising:
 a body; and   an eccentric portion fitted over the body and provided with at least one of a flexible structure and an oil pressure surface, wherein the flexible structure is configured to deform inwards when subject to an external force in an inward direction, and the oil pressure surface is configured in such a way that in a direction opposite to a rotating direction of a rotating central axis of the crankshaft, a distance between a front end of the oil pressure surface and the central axis of the eccentric portion is smaller than a distance between a tail end of the oil pressure surface and the central axis of the eccentric portion.   
     
     
         2 . The crankshaft for a rotary compressor according to  claim 1 , wherein the eccentric portion is provided with the flexible structure;
 the flexible structure has a first end and a second end, the first end of the flexible structure being connected to a first side wall of the eccentric portion and the second end of the flexible structure being spaced apart from the first side wall of the eccentric portion.   
     
     
         3 . The crankshaft for a rotary compressor according to  claim 2 , wherein the oil pressure surface is formed on a second side wall, opposite to the second end of the flexible structure, of the eccentric portion. 
     
     
         4 . The crankshaft for a rotary compressor according to  claim 3 , wherein the oil pressure surface is formed to be a smooth curved surface or a combination of a curved surface and a flat surface. 
     
     
         5 . The crankshaft for a rotary compressor according to  claim 2 , wherein the flexible structure and the central axis of the eccentric portion are located at a same side of a central axis of the body. 
     
     
         6 . The crankshaft for a rotary compressor according to  claim 5 , wherein the first end and the second end of the flexible structure are located at two sides of a reference plane respectively, and the reference plane is a plane formed by the central axis of the eccentric portion and the central axis of the body. 
     
     
         7 . The crankshaft for a rotary compressor according to  claim 6 , wherein a distance d 2  between the farthest point from the central axis of the eccentric portion, among intersection points of the flexible structure and the reference plane, and the central axis of the eccentric portion satisfies: d 2 ≧R 0 , wherein R 0  is an outer radius of the eccentric portion. 
     
     
         8 . The crankshaft for a rotary compressor according to  claim 1 , wherein the eccentric portion is provided with the flexible structure;
 the flexible structure has a first end and a second end, both the first end and the second end of the flexible structure being connected to a side wall of the eccentric portion and other portions of the flexible structure except the first end and the second end being spaced apart from the side wall of the eccentric portion.   
     
     
         9 . The crankshaft for a rotary compressor according to  claim 1 , wherein the eccentric portion is provided with the oil pressure surface, and 
       two ends of the oil pressure surface in an axial direction of the eccentric portion are adjacent to two end faces of the eccentric portion respectively. 
     
     
         10 . The crankshaft for a rotary compressor according to  claim 9 , wherein the two ends of the oil pressure surface adjoin the respective end faces of the eccentric portion directly. 
     
     
         11 . The crankshaft for a rotary compressor according to  claim 1 , wherein the eccentric portion is provided with the oil pressure surface, and a communicating oil hole communicated with a central oil hole of the body is formed in the oil pressure surface. 
     
     
         12 . A rotary compressor, comprising:
 a casing;   a compressing mechanism disposed in the casing and having a working chamber; and   a crankshaft for a rotary compressor,   the crankshaft for the rotary compressor comprises:
 a body; and
 an eccentric portion fitted over the body and provided with at least one of a flexible structure and an oil pressure surface, wherein the flexible structure is configured to deform inwards when subject to an external force in an inward direction, and the oil pressure surface is configured in such a way that in a direction opposite to a rotating direction of a rotating central axis of the crankshaft, a distance between a front end of the oil pressure surface and the central axis of the eccentric portion is smaller than a distance between a tail end of the oil pressure surface and the central axis of the eccentric portion, 
 
   wherein an end of the crankshaft goes through the compressing mechanism, and the eccentric portion of the crankshaft is located in the working chamber.   
     
     
         13 . A refrigerating cycle device, comprising a rotary compressor, the rotary compressor comprises:
 a casing;   a compressing mechanism disposed in the casing and having a working chamber; and   a crankshaft for a rotary compressor, the crankshaft for the rotary compressor comprises:
 a body; and
 an eccentric portion fitted over the body and provided with at least one of a flexible structure and an oil pressure surface, wherein the flexible structure is configured to deform inwards when subject to an external force in an inward direction, and the oil pressure surface is configured in such a way that in a direction opposite to a rotating direction of a rotating central axis of the crankshaft, a distance between a front end of the oil pressure surface and the central axis of the eccentric portion is smaller than a distance between a tail end of the oil pressure surface and the central axis of the eccentric portion, 
 
   wherein an end of the crankshaft goes through the compressing mechanism, and the eccentric portion of the crankshaft is located in the working chamber.   
     
     
         14 . The crankshaft for a rotary compressor according to  claim 5 , wherein the oil pressure surface is formed on a second side wall, opposite to the second end of the flexible structure, of the eccentric portion. 
     
     
         15 . The crankshaft for a rotary compressor according to  claim 14 , wherein the oil pressure surface is formed to be a smooth curved surface or a combination of a curved surface and a flat surface. 
     
     
         16 . The crankshaft for a rotary compressor according to  claim 14 , wherein the oil pressure surface is formed on a second side wall, opposite to the second end of the flexible structure, of the eccentric portion. 
     
     
         17 . The crankshaft for a rotary compressor according to  claim 15 , wherein the oil pressure surface is formed to be a smooth curved surface or a combination of a curved surface and a flat surface. 
     
     
         18 . The crankshaft for a rotary compressor according to  claim 7 , wherein the oil pressure surface is formed on a second side wall, opposite to the second end of the flexible structure, of the eccentric portion. 
     
     
         19 . The crankshaft for a rotary compressor according to  claim 18 , wherein the oil pressure surface is formed to be a smooth curved surface or a combination of a curved surface and a flat surface. 
     
     
         20 . The crankshaft for a rotary compressor according to  claim 11 , wherein the eccentric portion is provided with the flexible structure;
 the flexible structure has a first end and a second end, the first end of the flexible structure being connected to a first side wall of the eccentric portion and the second end of the flexible structure being spaced apart from the first side wall of the eccentric portion.