Scroll Compressor

Abstract

In a scroll compressor, it is hard to zone a high pressure chamber and a back pressure chamber which are formed in a back face of an orbiting scroll by a sealing means, increase a feeding amount to the high pressure chamber and the back pressure chamber at a low speed and adjust it at a high speed. A sealing means sealing a high pressure chamber in a center portion of a back face of an orbiting scroll and a back pressure chamber formed by an outer peripheral portion is provided, and a spiral shaped throttle passage is provided between a boss portion in the back face of the orbiting scroll and an outer peripheral surface of an orbiting bearing, thereby constructing an oil feeding route for feeding a lubricating oil to the back pressure chamber from the high pressure chamber.

1 . A scroll compressor comprising:
 a compression chamber formed by engaging a fixed scroll and an orbiting scroll with each other, each of which has an end plate and a spiral lap provided in a rising manner in said end plate;   a crank shaft making said orbiting scroll carry out a turning motion;   an orbiting bearing portion engaging said orbiting scroll and an eccentric pin portion of said crank shaft so as to be movable in a direction of a rotating axis and be rotatable and provided in a back face of the orbiting scroll;   a main bearing portion arranging a support portion which rotatably engages said crank shaft in a center portion of a frame member;   a back pressure chamber zoned by a seal member which is arranged between the back face of said orbiting scroll and the frame member;   a high pressure chamber zoned in an inner side of said seal member being maintained at a pressure which is approximately equal to a discharge pressure; and   the back pressure chamber zoned in an outer side of said seal member being maintained at a pressure which is lower than the discharge pressure,   wherein a spiral shaped groove passage is formed in an outer peripheral surface of the orbiting bearing, and a throttle passage communicating with the back pressure chamber is arranged so as to be provided with such the throttle passage as to be capable of continuously feeding a lubricating oil to the back pressure chamber from the high pressure chamber.   
     
     
         2 . A scroll compressor as claimed in  claim 1 , wherein the spiral shaped groove passage is formed in an inner peripheral surface of a boss portion in the back face of the orbiting scroll, and the throttle passage communicating with the back pressure chamber is arranged so as to be provided with such the throttle passage as to be capable of continuously feeding the lubricating oil to the back pressure chamber from the high pressure chamber. 
     
     
         3 . A scroll compressor as claimed in  claim 1 , wherein the spiral shaped groove passage is formed in an outer peripheral surface of said orbiting bearing, and the throttle passage communicating with an end surface of a turning boss portion is arranged so as to be provided with such the throttle passage as to be capable of intermittently feeding the lubricating oil to the back pressure chamber from the high pressure chamber. 
     
     
         4 . A scroll compressor as claimed in  claim 2 , wherein the spiral shaped groove passage is formed in an inner peripheral surface of a boss portion in a back face of said orbiting scroll, and the throttle passage communicating with an end surface of a turning boss portion is arranged so as to be provided with such the throttle passage as to be capable of intermittently feeding the lubricating oil to the back pressure chamber from the high pressure chamber. 
     
     
         5 . A scroll compressor as claimed in  claim 1 , wherein said orbiting bearing employs a winding bush which is formed as a cylindrical shape by rolling a flat plate, and a groove which is diagonal in a state of the flat plate or a rectangular groove is applied in accordance with a press molding or an etching process. 
     
     
         6 . A scroll compressor as claimed in  claim 2 , wherein said orbiting bearing employs a winding bush which is formed as a cylindrical shape by rolling a flat plate, and a groove which is diagonal in a state of the flat plate or a rectangular groove is applied in accordance with a press molding or an etching process. 
     
     
         7 . A scroll compressor as claimed in  claim 3 , wherein said orbiting bearing employs a winding bush which is formed as a cylindrical shape by rolling a flat plate, and a groove which is diagonal in a state of the flat plate or a rectangular groove is applied in accordance with a press molding or an etching process. 
     
     
         8 . A scroll compressor as claimed in  claim 4 , wherein said orbiting bearing employs a winding bush which is formed as a cylindrical shape by rolling a flat plate, and a groove which is diagonal in a state of the flat plate or a rectangular groove is applied in accordance with a press molding or an etching process. 
     
     
         9 . A scroll compressor comprising:
 a crank shaft having an eccentric pin portion;   an orbiting scroll having an orbiting bearing to which said eccentric pin portion is inserted;   a fixed scroll forming a compression chamber by being engaged with said orbiting scroll; and   a volumetric capacity of said compression chamber being changed by pressing said orbiting scroll to said fixed scroll on the basis of a pressure of a back pressure chamber and turning said orbiting scroll on the basis of a rotation of said crank shaft so as to compress a refrigerant,   wherein a high pressure chamber is formed between an end surface of said eccentric pin portion and a back face of said orbiting scroll,   wherein a throttle passage is provided between said eccentric pin portion and said orbiting bearing, and   wherein said orbiting scroll is provided with a discharge passage which introduces an oil to said back pressure chamber from said high pressure chamber via said throttle passage.   
     
     
         10 . A scroll compressor as claimed in  claim 9 , wherein said throttle passage is formed as a spiral shape.