Pipe joint made of resin

Abstract

The present invention relates to a pipe joint made of resin used for laying pipes in which a high-purity liquid, ultra pure water or the like flow. According to the pipe joint of the present invention, a sealing surface pressure is generated in both axial and radial directions, providing thereby an excellent sealing property for a long period, and facilitate controlling a torque for fastening a pushing ring. The pipe joint made of resin according to the present invention comprises a joint body having a receiving port, a cylindrical portion, an annular groove portion and a stepped surface. An inner ring forcedly inserted by the pushing ring is provided with an outer projection, an inner projection and an annular recessed portion. On at least one portion among axially opposed portions of each surface, an axial sealing portion is disposed. On at least one portion among radially opposed portions of each surface, an radial sealing portion is disposed. The joint body, the inner ring and the pushing ring are individually made of an optional synthetic resin selected among PFA, PTFE, ETFE, CTFE, and ECTFE.

1. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
 said joint body has a cylindrical receiving port disposed on an end portion thereof;  
 said joint body further has a cylindrical portion protruding from an end portion thereof and inside of the said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;  
 said inner ring is sleeve-shaped and has a connecting portion and a protruding portion, said inner ring being insertable in the said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;  
 said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection; and  
 said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pressing portion having an integral, axially outwardly extending cylindrical protruding piece made of resin for receiving and engaging, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port.  
 
     
     
       2. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port;   
 A pipe joint made of resin according to  claim 1 , further wherein:  said joint body further has an annular stepped surface which protrudes from a base of said cylindrical portion in an inwardly radial direction;  
 said cylindrical portion has an end surface;  
 said annular inner projection has an end surface;  
 said annular recessed portion has a bottom surface; and  
 said annular groove has a grooved bottom surface such that when said pressing force is applied to said inner ring by the pressing portion of said pushing ring, (i) said annular stepped surface is axially opposed to said end surface of said annular inner projection, (ii) said end surface of said cylindrical portion is axially opposed to said bottom surface of said annular recessed portion, and (iii) said grooved bottom surface of said annular groove is axially opposed to said end surface of said annular outer projection, with the result that three axially opposed portions are disposed, and the opposed surfaces are overlapped with each other on at least a portion among the axially opposed portions thereby forming an axial sealing portion.  
 
     
     
       3. A pipe joint made of resin according to  claim 2 , wherein the stepped surface is overlapped with an end surface of the inner projection, thereby forming the axial sealing portion with the result that the stepped surface and the end surface of the inner projection are formed as a flat surface. 
     
     
       4. A pipe joint made of resin according to  claim 2 , wherein the stepped surface is overlapped with an end surface of the inner projection, thereby forming the axial sealing portion with the result that the stepped surface and the end surface of the inner projection are formed in a stepped state. 
     
     
       5. A pipe joint made of resin according to  claim 2 , wherein the stepped surface is overlapped with an end surface of the inner projection, thereby forming the axial sealing portion with the result that the stepped surface and the end surface of the inner projection are formed in a tapered state. 
     
     
       6. A pipe joint made of resin according to  claim 2 , wherein the stepped surface is overlapped with an end surface of the inner projection, thereby forming the axial sealing portion with the result that the stepped surface and the end surface of the inner projection are formed in a radially wavelike state. 
     
     
       7. A pipe joint made of resin according to  claim 2 , wherein the cylindrical portion is supported by the inner projection, from a radially inward direction. 
     
     
       8. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port;   
 A pipe joint made of resin according to  claim 1 , further wherein: 
 said cylindrical portion has an inner peripheral surface;  
 said annular recessed portion has an inside surface;  
 said annular groove portion has an inside surface and an outside surface; and  
 said annular outer projection has an inner peripheral surface and an outer surface, such that when said pressing force is applied to said inner ring by the pressing portion of said pushing ring, (i) said inner peripheral surface of said cylindrical portion is radially opposed to said inside surface of said annular recessed portion, (ii) said inside surface of said annular groove portion is radially opposed to said inner peripheral surface of said annular outer projection, and (iii) said outside surface of said annular groove portion is radially opposed to said outer surface of said annular outer projection, with the result that three radially opposed portions are disposed, and the opposed surfaces are overlapped with each other on at least a portion among the radially opposed portions, thereby forming a radial sealing portion.  
 
     
     
       9. A pipe joint made of resin according to  claim 8 , wherein the cylindrical portion is supported by the inner projection, from a radially inward direction. 
     
     
       10. A pipe joint made of resin according to  claim 8 , further wherein: said connecting portion includes a bulged portion annularly disposed on an outer surface thereof; and the outside surface of said annular groove portion is overlapped with said bulged portion to form the radial sealing portion. 
     
     
       11. A pipe joint made of resin according to  claim 10 , further wherein: a plurality of bulged portions are axially arranged in line on the outer surface of said connecting portion. 
     
     
       12. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port;   
 A pipe joint made of resin according to  claim 1 , further wherein: 
 said joint body further has an annular stepped surface which protrudes from a base of said cylindrical portion in an inwardly radial direction;  
 said cylindrical portion has an inner peripheral surface and an end surface;  
 said annular inner projection has an end surface;  
 said annular outer projection has an inner peripheral surface and an outer surface;  
 said annular recessed portion has a bottom surface and an inside surface;  
 said annular groove has a grooved bottom surface; and  
 said annular groove portion has an inside surface and an outside surface, such that when said pressing force is applied to said inner ring by the pressing portion of said pushing ring, (i) said an annular stepped surface is axially opposed to said end surface of said annular inner projection, (ii) said end surface of said cylindrical portion is axially opposed to said bottom surface of said annular recessed portion, and (iii) said grooved bottom surface of said annular groove portion is axially opposed to said end surface of said annular outer projection, with the result that three axially opposed portions are disposed, and the opposed surfaces are overlapped with each other on at least a portion among the axially opposed portions thereby forming an axial sealing portion, and (i′) said inner peripheral surface of said cylindrical portion is radially opposed to said inside surface of said annular recessed portion, (ii′) said inside surface of said annular groove portion is radially opposed to said inner peripheral surface of said annular outer projection, and (iii′) said outside surface of said annular groove portion is radially opposed to said outer surface of said annular outer projection, with the result that three radially opposed portions are disposed, and the opposed surfaces are overlapped with each other on at least a portion among the radially opposed portions, thereby forming a radial sealing portion.  
 
     
     
       13. A pipe joint made of resin according to  claim 12 , wherein the cylindrical portion is supported by the inner projection, from a radially inward direction. 
     
     
       14. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port;   
 A pipe joint made of resin according to  claim 1 , further wherein: 
 said pushing ring has a pressing portion;  
 a diameter of the pipe material in which said connecting portion is forcedly inserted, is increased by said connecting portion; as a result of which the outer surface of the pipe material is provided with a swelling portion in the shape of a chevron, including a tapered abutting surface whose diameter decreases as it proceeds to a tip of the pipe material, and a tapered receiving surface whose diameter increase as it proceeds to a tip of the pipe material;  
 a tip of said cylindrical receiving port is provided with a tapered receiving surface forcedly abutting against said tapered abutting surface, toward a tip of said cylindrical receiving port; and  
 a radially smaller end portion of said tapered receiving surface on a side of the pipe material, whose diameter is smaller than the other end portion thereof, is subjected to said pressing force pressing it in a pressing direction by said pressing portion of said pushing ring.  
 
     
     
       15. A pipe joint made of resin according to  claim 14 , wherein a cylindrical overlapping piece overlapped with the receiving surface is continuously formed on the pressing portion of the pushing ring, by mounting the overlapping piece on the receiving surface on a side of the pipe material to increase the diameter in a state of widening a tip thereof. 
     
     
       16. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port; and   
 A pipe joint made of resin according to  claim 1 ,  wherein the cylindrical portion is supported by the inner projection, from a radially inward direction.  
 
     
     
       17. A pipe joint made of resin, including a joint body defining an inside area, an inner ring, and a pushing ring, an end portion of a pipe being adapted for insertion in said inside area of said joint body, the end portion of the pipe being pressed by said pushing ring against said joint body in said inside area of said joint body, thereby connecting the pipe to said joint body, wherein:
   said joint body has a cylindrical receiving port disposed on an end portion thereof;    
   said joint body further has a cylindrical portion protruding from an end portion thereof and inside of said cylindrical receiving port concentrically therewith, said cylindrical receiving port and said cylindrical portion defining an annular groove between them;    
   said inner ring is sleeve - shaped and has a connecting portion and a protruding portion, said inner ring being insertable in said receiving port, such that said connecting portion is forcedly inserted in the end portion of the pipe so as to be connected to the pipe, said protruding portion protruding from the end portion of the pipe and in said receiving port when said connecting portion is connected to the end of the pipe;    
   said protruding portion has an annular outer projection and an annular inner projection both axially protruding therefrom, said annular outer projection being inserted in said annular groove on the outside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular inner projection being inserted on the inside of said cylindrical portion by inserting said protruding portion of said inner ring in said receiving port, said annular outer projection and said annular inner projection defining an annular recessed portion disposed between said annular outer projection and said annular inner projection;    
   said pushing ring has a pressing portion disposed thereon and is threadedly connected to said cylindrical receiving port, said pushing ring applying a pressing force with said pressing portion for pressing against said inner ring when said inner ring is connected to the end portion of the pipe and said cylindrical protruding portion is inserted in said receiving port, and when said pushing ring is threadedly connected to said receiving port; and    
 A pipe joint made of resin according to  claim 1 ,  wherein the inner ring and the pushing ring are individually made of an optional synthetic resin selected among PFA, PTFE, ETFE, CTFE, and ECTFE.