JP2007105749A - Connecting pipe for fluid passages, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting pipe for fluid passage and manufacturing method thereof with which a leaking spots is little and a manufacturing cost is drastically reduced and this pipe can be provided at a low cost. <P>SOLUTION: This connecting pipe is arranged with a truncated cone-shaped head part 13 at the one end of the pipe body 12 and a guide projecting part 14 for positioning, projected on the top surface of the head part 13. The connecting pipe 11 arranging a communicating hole 16 for communicating a through-hole 15 of the pipe body 12 with the head part 13 and the guide projecting part 14, is heading and integrally shaped by using a metal material. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a connection pipe for a fluid passage which is attached to a main body case of a compressor used for, for example, a refrigerator, an air conditioner and the like, and is used for passing a refrigerant gas, and a manufacturing method thereof.

  Conventionally, this type of fluid passage connection pipe has a structure as shown in FIG. 4 in order to be fixed to an iron body case by resistance welding. That is, the gas passage connection pipe 1 includes a copper pipe body 2 having a predetermined diameter and length, a truncated cone-shaped head part 5 at one end of a cylindrical part 4 closely fitted to the pipe body 2, and A positioning guide projection 6 protruding from the top surface of the head 5 is connected to the head 5 and the guide projection 6 is provided with a communication hole 7 communicating with the pipe body 2. In order to prevent gas from leaking from the fitting connection location between the pipe body 2 and the connection body 3, the base end portion of the cylindrical portion 4 (the portion adjacent to the head portion 5) is formed. The solder ring 8 is fitted, the open end 2a of the pipe body 2 is soldered to the seating surface of the head 5 to ensure an airtight state, and the pipe body 2 and the connection body 3 are joined.

  The connection pipe 1 having the above structure is positioned by fitting the guide protrusion 6 of the connection body 3 to the attachment port 10 of the main body case 9, and resistance welding with the head 5 in contact with the periphery of the attachment port 10. It is fixed to the main body case 9 and used as a gas passage.

However, the above-described conventional connection pipe 1 is composed of two parts, a copper pipe body 2 and an iron connection body 3, and it is difficult to automate the soldering of both parts. There was a problem. In addition, since the pipe body 2 is made of copper whose price is soaring, the material cost tends to increase.
JP-A-11-319995

  The present invention has been made for the purpose of solving the above-mentioned conventional problems, and by integrally forming the pipe body and the connection body with a metal material, the number of leak points is reduced and the manufacturing cost is greatly increased. A connection pipe for a fluid passage that can be provided at a reduced cost and a method for manufacturing the same.

  In order to achieve the above object, a connecting pipe for a fluid passage according to the present invention has a truncated cone-shaped head at one end of a pipe body having a predetermined diameter and length, and a top surface of the head. And a guide pipe for positioning, and a connecting pipe in which the head and the guide protrusion are provided with a communication hole communicating with the through hole of the pipe body is integrally formed by forging a metal material. It is characterized by.

  The metal material is preferably soft iron with a low material cost, and the manufactured connection pipe is annealed and then subjected to copper plating, zinc plating, tin plating, nickel plating, and other surface treatments. .

  In addition, the method of manufacturing the connection pipe for fluid passage according to the present invention includes a preparation step of cutting a metal wire to form a cylindrical material having a predetermined diameter and length, and a truncated cone part at one end of the cylindrical material. A pre-forming step of processing a short guide protrusion protruding from the top surface of the frustoconical part, and extruding the columnar material portion including the frustoconical part and the guide protrusion to increase the diameter. A frustoconical head, a head forging step for forming a guide projection for positioning having a diameter smaller than the diameter of the cylindrical material, and forming a preliminary hole in the guide projection, and the frustoconical head Extruding the columnar material continuous to the part to forge-mold a pipe body having a through hole; punching the frustoconical head through the preliminary hole part; The pipe body on the guide and the projecting protrusion Including a finishing step of connecting pipe provided with a communication hole communicating with the through-hole is completed, the.

  Subsequent to the finishing step, the connection pipe may be annealed and then include copper plating, zinc plating, tin plating, nickel plating, and other surface treatment steps.

  As described above, according to the present invention, the connection pipe having the truncated cone-shaped head and the positioning guide protrusion is integrally formed at one end of the pipe body with the metal material. Compared to the manufactured conventional products, the number of leak points is reduced, which is advantageous for handling. Moreover, not only can manufacturing costs and material costs be greatly reduced, but also mass production is possible and can be provided at low cost.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 show a gas pipe connection pipe 11 according to the present invention, which is manufactured by forging a ferrous metal material, for example, a soft iron wire, and has a pipe body 12 having a predetermined diameter and length. At one end, a truncated cone-shaped head 13 and a positioning guide protrusion 14 projecting from the top surface of the head 13 are integrally formed, and the pipe body 12 is connected to the head 13 and the guide protrusion 14. In this structure, a communication hole 16 communicating with the through hole 15 is provided. The connection pipe 11 is entirely plated with copper.

  FIG. 3 shows a manufacturing process of the method of the present invention for manufacturing the connection pipe 11 having the above-described integrated structure.

  As shown in FIG. 3A, the manufacturing process includes a preparatory process of cutting a soft iron wire rod to form a conical material 20 having a predetermined diameter (8 mm) and length (25 mm), and FIG. As shown in FIG. 3B, a preforming step for machining a truncated cone-shaped portion 21 at one end of the columnar material 20 and a short guide protruding portion 22 protruding from the top surface of the truncated cone-shaped portion 21; ), A columnar material 20 portion including the truncated cone part 21 and the guide protrusion 22 is extruded to have a large truncated cone-shaped head part 23 bulging in the radial direction, and the columnar material 20. And a head forging step of forming a preliminary recess 25 in the guide protrusion 24 and a truncated cone-shaped head 23 as shown in FIG. 3 (d). A pipe body having a through-hole 15 by extruding a cylindrical material 20 continuous with As shown in FIG. 3 (e), the truncated cone-shaped head portion 23 is punched from the guide protrusion 24 through the preliminary hole portion 25, and the truncated cone-shaped head portion 23 is formed. (13) and the guide protrusion 24 (14) are provided with a communication hole 16 communicating with the through hole 15 of the pipe body 12 to complete the connection pipe 11, and the connection pipe 11 is completely completed following the finishing process. It consists of a surface treatment process for copper plating after annealing. In the surface treatment step, not only copper plating but also zinc plating, tin plating, nickel plating, and other surface treatments may be performed.

  In the above-described embodiment, soft iron is used as the columnar material 20, but it is possible to employ an aluminum alloy, carbon steel, or other metal material in addition to soft iron.

It is a partial longitudinal front view of the connection pipe for fluid passages by the present invention. It is a top view same as the above. The manufacturing process by this invention method is shown, (a) is a preparation process, (b) is a preforming process, (c) is a head forging process, (d) is a pipe forging process, and (e) is a finishing process. is there. It is a vertical front view which shows the structure and usage example of the conventional connection pipe for gas passages.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Connection pipe for fluid passages 12 Pipe main body 13 (23) Frustum-shaped head 14 (24) Positioning guide protrusion 15 Through hole 16 Communication hole 20 Columnar material 21 Frustum head 22 Short guide protrusion 25 Preliminary Hole

Claims (4)

  One end of a pipe body having a predetermined diameter and length is provided with a truncated cone-shaped head, and a positioning guide protrusion protruding from the top surface of the head, the head and the guide protrusion. A connection pipe for a fluid passage, wherein a connection pipe provided with a communication hole communicating with the through hole of the pipe body is integrally formed by forging a metal material.   The connection pipe for fluid passage according to claim 1, wherein the connection pipe is integrally formed by forging soft iron and surface-treated. A preparation step of cutting a metal wire to form a cylindrical material having a predetermined diameter and length;
A preforming step of processing a truncated cone part at one end of the columnar material and a short guide protrusion protruding from the top surface of the truncated cone part;
The columnar material portion including the frustoconical portion and the guide protrusion is extruded to form a large truncated cone head and a guide protrusion for positioning having a diameter smaller than the diameter of the columnar material. And head forging step of forming a preliminary hole in the guide protrusion,
A pipe forging process for extruding the cylindrical material continuous to the truncated cone-shaped head and forging a pipe body having a through hole; and
A finishing step in which the truncated cone-shaped head is punched through the preliminary hole, and a connection hole is formed in the head and the guide protrusion to communicate with the through hole of the pipe body, thereby completing a connection pipe; ,
A method for manufacturing a connection pipe for a fluid passage including   The manufacturing method of the connection pipe for fluid passages of Claim 3 including a surface treatment process after annealing the said connection pipe following the said finishing process.

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