Oil Separator

Abstract

Provided is an oil separator which can separate refrigerant and refrigeration machine oil with high efficiency, which can effectively prevent the outflow of separated oil towards the refrigerant discharge path side, which can reduce pressure loss in the flow of refrigerant, and which can be made compact especially in the radial direction. The oil separator is provided with: a tubular outer pipe which is disposed on the compressor outlet side; an inlet pipe for introducing refrigerant containing refrigeration machine oil into the tubular outer pipe in such a manner as to produce a downward helical flow of refrigerant containing refrigeration machine oil along the inner surface of the tubular outer pipe; a refrigerant outlet pipe which has an external outflow port for the outflow of refrigerant to outside the tubular outer pipe, has a section extending in the axial direction of the tubular outer pipe at the central position of the tubular outer pipe, and allows the inflow, from the lower end of the above-mentioned section, of refrigerant separated from the refrigerant containing refrigeration machine oil having flowed down in the helical flow, and wherein the flow direction has been inverted in relation to the vertical direction at a first refrigerant inversion part; a refrigerant return pipe which extends in the axial direction of the tubular outer pipe at the central position of the tubular outer pipe, below the refrigerant outlet pipe, and which allows the inflow, from the lower end thereof, of refrigerant separated from the refrigerant containing refrigeration machine oil having flowed down in the helical flow, and wherein the flow direction has been inverted in relation to the vertical direction at a second refrigerant inversion part; and an oil storage part which is formed at the bottom of the tubular outer pipe. Furthermore, a part exhibiting a reflector function for preventing refrigeration machine oil stored in the oil storage part from flowing out into the refrigerant outlet pipe is provided between the refrigerant return pipe and the inner surface of the tubular outer pipe.

1 . An oil separator comprising:
 a tubular outer pipe which is disposed on a compressor outlet side so as to extend in a vertical direction;   an inlet pipe provided at an upper part of said tubular outer pipe for introducing refrigerant containing refrigeration machine oil, discharged from a compressor, into said tubular outer pipe in such a manner as to produce a downward helical flow of refrigerant containing refrigeration machine oil along an inner surface of said tubular outer pipe;   a refrigerant outlet pipe which has an external outflow port at an upper end for flowing out refrigerant to outside said tubular outer pipe, has a section extending in an axial direction of said tubular outer pipe at a central position of said tubular outer pipe, and has a first refrigerant inflow port at a lower end of said section for flowing in refrigerant therein, which has been separated from refrigerant containing refrigeration machine oil having flowed down in said helical flow and the flow direction of which has been inverted in relation to vertical direction at a first refrigerant inversion part;   a refrigerant return pipe which extends in an axial direction of said tubular outer pipe at a central position of said tubular outer pipe, below said refrigerant outlet pipe, has a refrigerant communication port at an upper end for being confronted with or connected to a lower end of said refrigerant outlet pipe, and has a second refrigerant inflow port at a lower end for flowing in refrigerant therein, which has been separated from refrigerant containing refrigeration machine oil having flowed down in said helical flow and the flow direction of which has been inverted in relation to vertical direction at a second refrigerant inversion part; and   an oil storage part, which is formed at a bottom of said tubular outer pipe, capable of temporarily storing refrigeration machine oil separated from refrigerant,   wherein a part exhibiting a reflector function for preventing refrigeration machine oil stored in said oil storage part from flowing out into said refrigerant outlet pipe is provided between said refrigerant return pipe and said inner surface of said tubular outer pipe.   
     
     
         2 . The oil separator according to  claim 1 , wherein said refrigerant return pipe comprises a tubular pipe having a constant diameter which extends upwardly from said second refrigerant inversion part, and said part exhibiting a reflector function comprises a bevel part which extends from an upper end of said tubular pipe toward an obliquely downward direction and which is enlarged in diameter as located at a lower position. 
     
     
         3 . The oil separator according to  claim 1 , wherein said refrigerant return pipe comprises a bell mouth type pipe which extends upwardly from said second refrigerant inversion part and which is enlarged in diameter as located at an upper position, and said part exhibiting a reflector function is formed from said bell mouth type pipe. 
     
     
         4 . The oil separator according to  claim 1 , wherein said refrigerant return pipe comprises a tubular pipe part having a constant diameter which extends upwardly from said second refrigerant inversion part and a bell mouth type pipe part which extends upwardly from an upper end of said tubular pipe part and which is enlarged in diameter as located at an upper position, and said part exhibiting a reflector function is formed from said bell mouth type pipe part. 
     
     
         5 . The oil separator according to  claim 1 , wherein said refrigerant outlet pipe and said refrigerant return pipe are formed as an integrated tubular pipe having a connection part therebetween, an opening as said first refrigerant inflow port is formed on a pipe wall of said refrigerant outlet pipe positioned above said connection part, and said part exhibiting a reflector function comprises a bevel part which extends from said connection part or the vicinity thereof toward an obliquely downward direction and which is enlarged in diameter as located at a lower position. 
     
     
         6 . The oil separator according to  claim 1 , wherein said refrigerant return pipe comprises a first bell mouth type pipe part which extends upwardly from said second refrigerant inversion part and which is enlarged in diameter as located at an upper position, and a second bell mouth type pipe part which is connected to an upper end of said first bell mouth type pipe part and which is contracted in diameter as located at an upper position, a lower end of said refrigerant outlet pipe is connected to an upper end of said refrigerant return pipe at a connection part to form an integrated pipe structure, an opening as said first refrigerant inflow port is formed on a pipe wall of said refrigerant outlet pipe positioned above said connection part, and said part exhibiting a reflector function is formed from said first bell mouth type pipe part. 
     
     
         7 . The oil separator according to  claim 1 , wherein said refrigerant return pipe comprises a tubular pipe part having a constant diameter which extends upwardly from said second refrigerant inversion part, a first bell mouth type pipe part which extends upwardly from an upper end of said tubular pipe part and which is enlarged in diameter as located at an upper position, and a second bell mouth type pipe part which is connected to an upper end of said first bell mouth type pipe part and which is contracted in diameter as located at an upper position, a lower end of said refrigerant outlet pipe is connected to an upper end of said refrigerant return pipe at a connection part to form an integrated pipe structure, an opening as said first refrigerant inflow port is formed on a pipe wall of said refrigerant outlet pipe positioned above said connection part, and said part exhibiting a reflector function is formed from said first bell mouth type pipe part. 
     
     
         8 . The oil separator according to  claim 1 , wherein at least said refrigerant return pipe is supported relative to said inner surface of said tubular outer pipe via a bracket at a condition where a path for refrigerant containing refrigeration machine oil is ensured. 
     
     
         9 . The oil separator according to  claim 1 , wherein an oil return tube for returning refrigeration machine oil stored in said oil storage part to a compressor is connected to said oil separator. 
     
     
         10 . The oil separator according to  claim 1 , wherein said oil separator is disposed between a compressor and a condenser in a refrigeration circuit having said compressor, said condenser, an expansion mechanism and an evaporator in this order. 
     
     
         11 . The oil separator according to  claim 10 , wherein said oil separator is built in a header pipe of said condenser, and said external outflow port of said refrigerant outlet pipe is opened toward inside of said header pipe. 
     
     
         12 . The oil separator according to  claim 11 , wherein said header pipe and said tubular outer pipe are formed integrally by extrusion molding. 
     
     
         13 . The oil separator according to  claim 1 , wherein said oil separator is provided in a refrigeration circuit of an air conditioning system for a vehicle.