Expansion Valve

Abstract

An expansion valve relating to the field of air conditioning technology. The present expansion valve comprises a housing, a cylindrical valve body with an inner cavity fixed inside the housing. In the inner cavity, there is a matched set of the first valve core and the second valve core sliding along it. A retaining ring is fixed in the inner cavity between the two valve cores. At both ends of the inner cavity there are spring assemblies driving the valve cores towards the retaining ring. A damping structure is also installed between the first valve core and the second valve core. In this manner, a cushioning effect is provided when the first valve core approaches the second valve core, which lightens the impacts to valve cores and thereby extend the service life of the expansion valve.

What is claimed is: 
     
         1 . An expansion valve comprising:
 a housing ( 10 ) with an inlet end ( 101 ) and an outlet end ( 102 );   a cylindrical valve body ( 1 ) with an inner cavity fixed inside the housing ( 10 );   an inlet ( 11 ) and an outlet ( 12 ) provided on a side wall of the valve body ( 1 ), connecting the inner cavity and the housing ( 10 );   a spacer sleeve ( 8 ) between the housing ( 10 ) and valve body ( 1 ) that separates the inlet ( 11 ) and outlet ( 12 );   a matched pair of a first valve core ( 2 ) and a second valve core ( 3 ) capable of sliding along an interior of inner cavity;   a retaining ring ( 7 ) fixed to a mid-section of the inner cavity between the first valve core ( 2 ) and the second valve core ( 3 );   spring assemblies at both ends of the inner cavity, pressing the first valve core ( 2 ) and the second valve core ( 3 ) towards the retaining ring ( 7 ); and   a damping structure provided between the first valve core ( 2 ) and the second valve core ( 3 ), which provides a cushioning effect.   
     
     
         2 . The expansion valve as claimed in  claim 1 , further comprising:
 a guide bore ( 73 );   an annular cavity ( 74 );   a diversion hole ( 71 ) connecting the annular cavity ( 74 ) and the inlet ( 11 ); and   a limiter groove ( 72 ) capable of securing a press fit to the valve body ( 1 ).   
     
     
         3 . The expansion valve as claimed in  claim 1 , wherein:
 the front cylinder ( 21 ), the front throttle cone ( 22 ), the rear cylinder ( 23 ), the rear throttle cone ( 24 ), and the guide cylinder ( 25 ) are structures on the head of the first valve core ( 2 ) and positioned in sequential order; and   the front cylinder bore ( 36 ), the front throttle cone bore ( 35 ), the relief groove ( 33 ), the rear cylinder bore ( 32 ), and the rear throttle cone bore ( 31 ) on the second valve core ( 3 ) are positioned in reverse sequential order and match the corresponding structures on the head of the first valve core ( 2 );   wherein a diversion port ( 37 ) connects the front cylinder bore ( 36 ) and the outlet ( 12 ) on the second valve core ( 3 ).   
     
     
         4 . The expansion valve as claimed in  claim 2 , wherein:
 the front cylinder ( 21 ), the front throttle cone ( 22 ), the rear cylinder ( 23 ), the rear throttle cone ( 24 ), and the guide cylinder ( 25 ) are structures on the head of the first valve core ( 2 ) and positioned in sequential order; and   the front cylinder bore ( 36 ), the front throttle cone bore ( 35 ), the relief groove ( 33 ), the rear cylinder bore ( 32 ), and the rear throttle cone bore ( 31 ) on the second valve core ( 3 ) are positioned in reverse sequential order and match the corresponding structures on the head of the first valve core ( 2 );   wherein a diversion port ( 37 ) connects the front cylinder bore ( 36 ) and the outlet ( 12 ) on the second valve core ( 3 ).   
     
     
         5 . The expansion valve as claimed in  claim 3 , further comprising:
 a vent ( 34 ) connecting the outside of the valve body ( 1 ) and the relief groove ( 33 ) on the second valve core ( 3 ).   
     
     
         6 . The expansion valve as claimed in  claim 4 , further comprising:
 a vent ( 34 ) connecting the outside of the valve body ( 1 ) and the relief groove ( 33 ) on the second valve core ( 3 ).   
     
     
         7 . The expansion valve as claimed in  claim 3 , further comprising:
 a diversion slot ( 27 ) connecting the relief groove ( 33 ) and the front cylinder bore ( 36 ) on the first valve core ( 2 ).   
     
     
         8 . The expansion valve as claimed in  claim 4 , further comprising:
 a diversion slot ( 27 ) connecting the relief groove ( 33 ) and the front cylinder bore ( 36 ) on the first valve core ( 2 ).   
     
     
         9 . The expansion valve as claimed in  claim 3 , further comprising:
 a vent ( 38 ) connecting the relief groove ( 33 ) and the diversion port ( 37 ) on the second valve core.   
     
     
         10 . The expansion valve as claimed in  claim 4 , further comprising:
 a vent ( 38 ) connecting the relief groove ( 33 ) and the diversion port ( 37 ) on the second valve core.   
     
     
         11 . The expansion valve as claimed in  claim 3 , further comprising:
 a vent ( 39 ) connecting the rear throttle cone bore ( 31 ) and the front cylinder bore ( 36 ) on the first valve core ( 2 ).   
     
     
         12 . The expansion valve as claimed in  claim 4 , further comprising:
 a vent ( 39 ) connecting the rear throttle cone bore ( 31 ) and the front cylinder bore ( 36 ) on the first valve core ( 2 ).   
     
     
         13 . The expansion valve as claimed in  claim 3 , further comprising:
 a vent ( 34 ) axially passing throughout the first valve core ( 2 ).   
     
     
         14 . The expansion valve as claimed in  claim 4 , further comprising:
 a vent ( 34 ) axially passing throughout the first valve core ( 2 ).   
     
     
         15 . The expansion valve as claimed in  claim 5 , further comprising:
 a spring assembly having a first spring seat ( 43 ), a first spring ( 41 ), a second spring seat ( 44 ) and a second spring ( 42 ), with one end of the first spring ( 41 ) abutting the first valve core ( 2 ) and the other end abutting the first spring seat ( 43 ), with one end of the second spring ( 42 ) abutting the second valve core ( 3 ) and the other end abutting the second spring seat ( 44 ), and with the first spring seat ( 43 ) and the second spring seat ( 44 ) respectively affixed to each end of the valve body ( 1 );   a small hole ( 52 ) each at the end of the first spring seat ( 43 ) and the end of the second spring seat ( 44 ), venting to the housing ( 10 );   a cylinder ( 103 ) and a damping ring groove ( 26 ) each at the rear end of the first valve core ( 2 ) and the rear end of the second valve core ( 3 ); and   a damping ring ( 6 ) installed in each of the damping ring grooves ( 26 ).   
     
     
         16 . The expansion valve as claimed in  claim 6 , further comprising:
 a spring assembly having a first spring seat ( 43 ), a first spring ( 41 ), a second spring seat ( 44 ) and a second spring ( 42 ), with one end of the first spring ( 41 ) abutting the first valve core ( 2 ) and the other end abutting the first spring seat ( 43 ), with one end of the second spring ( 42 ) abutting the second valve core ( 3 ) and the other end abutting the second spring seat ( 44 ), and with the first spring seat ( 43 ) and the second spring seat ( 44 ) respectively affixed to each end of the valve body ( 1 );   a small hole ( 52 ) each at the end of the first spring seat ( 43 ) and the end of the second spring seat ( 44 ), venting to the housing ( 10 );   a cylinder ( 103 ) and a damping ring groove ( 26 ) each at the rear end of the first valve core ( 2 ) and the rear end of the second valve core ( 3 ); and   a damping ring ( 6 ) installed in each of the damping ring grooves ( 26 ).   
     
     
         17 . The expansion valve as claimed in  claim 15 , further comprising:
 a filter assembly ( 9 ) installed at the inlet end ( 101 ) and the outlet end ( 102 ) of the housing ( 10 ), the filter assembly ( 9 ) having a filter screen and a mounting racket fixed to the housing ( 10 ).   
     
     
         18 . The expansion valve as claimed in  claim 16 , further comprising:
 a filter assembly ( 9 ) installed at the inlet end ( 101 ) and the outlet end ( 102 ) of the housing ( 10 ), the filter assembly ( 9 ) having a filter screen and a mounting racket fixed to the housing ( 10 ).