Automatic Two-Way Expansion Valve

Abstract

An automatic two-way expansion valve that resolves the issue where the precision in flow control of existing expansion valves is low. This automatic two-way expansion valve comprises a valve body and the first and second valve cores inside the valve body. There is a small bore concatenate with a big bore inside second valve core. One end of first valve core passes through the big bore and plug into the small bore. There is a flow clearance between the end of first valve core and the sidewall of the small bore. There is a sealing cone on first valve core, which can press against the chamfer rim between the small bore and the big bore. It effectively improves the precision in flow control, by modifying the shape of the end of first valve core and adding the first and the second gaskets.

What is claimed is: 
     
         1 . An automatic two-way expansion valve comprising:
 a valve body ( 1 );   a first valve core ( 3 ) inside the valve body ( 1 );   a second valve core ( 4 ) inside the valve body ( 1 ); and   a small bore ( 4   a ) concatenate with a big bore ( 4   b ) inside second valve core ( 4 ), one end of first valve core ( 3 ) passes through the big bore ( 4   b ) and plugs into the small bore ( 4   a );   wherein there is a flow clearance between the end of first valve core ( 3 ) and the sidewall of the small bore ( 4   a );   wherein there is a sealing cone ( 3   a ) on first valve core ( 3 ), which is capable of pressing against a chamfer rim between the small bore ( 4   a ) and the big bore ( 4   b ).   
     
     
         2 . The automatic two-way expansion valve as claimed in  claim 1 , wherein the chamfer rim between the small bore ( 4   a ) and the big bore ( 4   b ) is an arc chamfer ( 4   c ). 
     
     
         3 . The automatic two-way expansion valve as claimed in  claim 1  wherein on one end of first valve core ( 3 ), from the sealing cone ( 3   a ) to the end face of the end, there is a big cylinder ( 3   c ) followed by a small cylinder ( 3   d ). 
     
     
         4 . The automatic two-way expansion valve as claimed in  claim 1  wherein on one end of first valve core ( 3 ), from the sealing cone ( 3   a ) to the end face of the end, there is a big cylinder ( 3   c ), which is followed by a flow transition section ( 3   e ), which is followed by a small cylinder ( 3   d ). 
     
     
         5 . The automatic two-way expansion valve as claimed in  claim 1  wherein the first valve core ( 3 ) is clasped by a guide valve seat ( 6 ), which is fastened to the valve body ( 1 );
 wherein there is the first vent ( 3   f ) on the other end face of first valve core ( 3 ), and there are several second vents ( 3   g ) on the sidewall of first valve core ( 3 ), connecting to the first vent; and 
 wherein the small bore ( 4   a ) passes throughout second valve core ( 4 ). 
 
     
     
         6 . The automatic two-way expansion valve as claimed in  claim 5  wherein the first gasket ( 10 ) is installed between one end face of the guide valve seat ( 6 ) and the end face of second valve core ( 4 ). 
     
     
         7 . The automatic two-way expansion valve as claimed in  claim 6  wherein the first valve core ( 3 ) comprises a seal abutment surface ( 3   b ); and
 wherein between the other end face of the guide valve seat ( 6 ) and the seal abutment surface ( 3   b ) of first valve core ( 3 ), the second gasket ( 11 ) is installed. 
 
     
     
         8 . The automatic two-way expansion valve as claimed in  claim 5  wherein bumping posts ( 5 ) are fixed to both ends of the valve body ( 1 ); and
 wherein there are slots ( 5   a ) on the side wall of the post, and there are auxiliary slots ( 5   b ) throughout in radial directions on the inner end faces of the bumping post ( 5 ). 
 
     
     
         9 . The automatic two-way expansion as claimed in  claim 1  wherein a protective sleeve ( 14 ) encases the valve body ( 1 ); and
 wherein both ends of the valve body ( 1 ) are tube fittings, located outside of the protective sleeve ( 14 ), and both ends of the protective sleeve ( 14 ) are fixed to the valve body ( 1 ) by welding. 
 
     
     
         10 . The automatic two-way expansion as claimed in  claim 1  wherein there are at least two seal grooves on the outer surfaces of first valve core ( 3 ) and second valve core ( 4 ); and
 wherein the second ring seal ( 7 ), pressing against the inner wall of the valve body ( 1 ), is embedded into each groove. 
 
     
     
         11 . The automatic two-way expansion valve as claimed in  claim 2  wherein the first valve core ( 3 ) is clasped by a guide valve seat ( 6 ), which is fastened to the valve body ( 1 );
 wherein there is the first vent ( 3   f ) on the other end face of first valve core ( 3 ), and there are several second vents ( 3   g ) on the sidewall of first valve core ( 3 ), connecting to the first vent; and 
 wherein the small bore ( 4   a ) passes throughout second valve core ( 4 ). 
 
     
     
         12 . The automatic two-way expansion as claimed in  claim 2  wherein a protective sleeve ( 14 ) encases the valve body ( 1 ); and
 wherein both ends of the valve body ( 1 ) are tube fittings, located outside of the protective sleeve ( 14 ), and both ends of the protective sleeve ( 14 ) are fixed to the valve body ( 1 ) by welding. 
 
     
     
         13 . The automatic two-way expansion as claimed in  claim 2  wherein there are at least two seal grooves on the outer surfaces of first valve core ( 3 ) and second valve core ( 4 ); and
 wherein the second ring seal ( 7 ), pressing against the inner wall of the valve body ( 1 ), is embedded into each groove. 
 
     
     
         14 . The automatic two-way expansion valve as claimed in  claim 3  wherein the first valve core ( 3 ) is clasped by a guide valve seat ( 6 ), which is fastened to the valve body ( 1 );
 wherein there is the first vent ( 3   f ) on the other end face of first valve core ( 3 ), and there are several second vents ( 3   g ) on the sidewall of first valve core ( 3 ), connecting to the first vent; and 
 wherein the small bore ( 4   a ) passes throughout second valve core ( 4 ). 
 
     
     
         15 . The automatic two-way expansion as claimed in  claim 3  wherein a protective sleeve ( 14 ) encases the valve body ( 1 ); and
 wherein both ends of the valve body ( 1 ) are tube fittings, located outside of the protective sleeve ( 14 ), and both ends of the protective sleeve ( 14 ) are fixed to the valve body ( 1 ) by welding. 
 
     
     
         16 . The automatic two-way expansion as claimed in  claim 3  wherein there are at least two seal grooves on the outer surfaces of first valve core ( 3 ) and second valve core ( 4 ); and
 wherein the second ring seal ( 7 ), pressing against the inner wall of the valve body ( 1 ), is embedded into each groove. 
 
     
     
         17 . The automatic two-way expansion valve as claimed in  claim 4  wherein the first valve core ( 3 ) is clasped by a guide valve seat ( 6 ), which is fastened to the valve body ( 1 );
 wherein there is the first vent ( 3   f ) on the other end face of first valve core ( 3 ), and there are several second vents ( 3   g ) on the sidewall of first valve core ( 3 ), connecting to the first vent; and 
 wherein the small bore ( 4   a ) passes throughout second valve core ( 4 ). 
 
     
     
         18 . The automatic two-way expansion as claimed in  claim 4  wherein a protective sleeve ( 14 ) encases the valve body ( 1 ); and
 wherein both ends of the valve body ( 1 ) are tube fittings, located outside of the protective sleeve ( 14 ), and both ends of the protective sleeve ( 14 ) are fixed to the valve body ( 1 ) by welding. 
 
     
     
         19 . The automatic two-way expansion as claimed in  claim 4  wherein there are at least two seal grooves on the outer surfaces of first valve core ( 3 ) and second valve core ( 4 ); and
 wherein the second ring seal ( 7 ), pressing against the inner wall of the valve body ( 1 ), is embedded into each groove.