Compressor

Abstract

A compressor includes two rotors opposed to each other in an axial direction, and a vane contacting the rotors. While the vane is moved in the axial direction with rotation of the rotors, the vane is restricted from rotating by a vane groove. The compressor includes compression chambers in which suction and compression of fluid are performed with rotation of the rotors, and a communication mechanism switched between a communicating state in which the compression chambers communicate with each other, and a non-communicating state in which the compression chambers do not communicate with each other.

1 . A compressor comprising:
 a rotary shaft;   a first rotor including a ring-shaped first rotor surface, and rotated with rotation of the rotary shaft;   a second rotor opposed to the first rotor in an axial direction of the rotary shaft, rotated with the rotation of the rotary shaft, and including a ring-shaped second rotor surface;   a first cylindrical portion including a first inner circumferential surface opposed to an outer circumferential surface of the first rotor in a radial direction of the rotary shaft, and housing the first rotor;   a second cylindrical portion including a second inner circumferential surface opposed to an outer circumferential surface of the second rotor in the radial direction, and housing the second rotor;   a wall portion arranged between the rotors, and including a first wall surface opposed to the first rotor surface in the axial direction, and a second wall surface opposed to the second rotor surface in the axial direction;   a vane contacting the rotor surfaces in a state where the vane is inserted into a vane groove formed in the wall portion, and moving in the axial direction with rotation of the rotors;   a first compression chamber formed by the first rotor surface, the first wall surface, and the first inner circumferential surface, a volume change of the first compression chamber being caused by the vane with rotation of the first rotor, such that suction and compression of fluid are performed;   a second compression chamber formed by the second rotor surface, the second wall surface, and the second inner circumferential surface, a volume change of the second compression chamber being caused by the vane with rotation of the second rotor, such that suction and compression of the fluid are performed; and   a communication mechanism switched between a communicating state in which the first compression chamber and the second compression chamber communicate with each other, and a non-communicating state in which the first compression chamber and the second compression chamber do not communicate with each other.   
     
     
         2 . The compressor according to  claim 1 , wherein
 a wall through-hole extending in the axial direction is formed in the wall portion,   a size in a radial direction of the wall through-hole is larger than a size in a radial direction of the rotary shaft, and   the communication mechanism includes
 a communication passage for communicating between the first compression chamber and the second compression chamber via a gap between the rotary shaft and an inner circumferential surface of the wall through-hole, and 
 a valve that moves between an open position for opening the communication passage and a closed position for closing the communication passage in accordance with angular positions of the rotors. 
   
     
     
         3 . The compressor according to  claim 2 , wherein
 the communication passage includes
 a communication groove recessed outward in the radial direction of the rotary shaft from the inner circumferential surface of the wall through-hole, 
 a first opening formed in the wall portion, and opened toward the first compression chamber and the wall through-hole, 
 a second opening formed at a position different from the first opening in the wall portion in a circumferential direction, and opened toward the second compression chamber and the wall through-hole, 
   the valve has a sectoral shape, and is arranged in the wall through-hole,   the valve includes a valve outer circumferential surface contacting the inner circumferential surface of the wall through-hole,   the communication groove communicates with one opening of the openings, and is separated from the other opening,   when the valve is arranged at the closed position, since the valve is arranged radially inside of the opening part opened to the wall through-hole of the other opening, the valve outer circumferential surface closes the opening part, and   when the valve is arranged at the open position, since the valve is arranged at a position shifted in the circumferential direction with respect to the opening part, movement of fluid is permitted from the first compression chamber to the second compression chamber via an open space that is formed in the wall through-hole and communicates with the communication groove.   
     
     
         4 . The compressor according to  claim 3 , wherein
 the communication mechanism includes
 a cylindrical first boss portion projecting toward the second rotor from a radially inner end of the first rotor surface, and 
 a second cylindrical boss portion projecting toward the first rotor from a radially inner end of the second rotor surface, 
   the valve is configured by
 a first engagement portion projecting toward the second rotor from a tip surface of the first boss portion, and 
 a second engagement portion projecting toward the first rotor from a tip surface of the second boss portion, and engaging with the first engagement portion in the circumferential direction, and 
   the valve outer circumferential surface is configured by outer circumferential surfaces of the engagement portions.   
     
     
         5 . The compressor according to  claim 1 , wherein
 the vane includes a first vane end and a second vane end as opposite ends in the axial direction,   the first rotor surface that the first vane end contacts includes a first curving surface displaced in the axial direction in accordance with angular positions of the rotors,   the second rotor surface that the second vane end contacts includes a second curving surface displaced in the axial direction in accordance with the angular positions of the rotors, and   the first curving surface and the second curving surface are opposed to each other in the axial direction, and are curved in the axial direction such that a separation distance is constant irrespective of the angular positions of the rotors.   
     
     
         6 . The compressor according to  claim 5 , wherein
 the first rotor surface includes a first flat surface provided at a position separated in the axial direction with respect to the first wall surface and perpendicular to the axial direction, and a second flat surface provided at a position separated in the circumferential direction with respect to the first flat surface, perpendicular to the axial direction, and contacting the first wall surface, and   the first curving surface connects the first flat surface with the second flat surface, and is curved to be gradually close to the first wall surface from the first flat surface to the second flat surface.