JP6429000B2 - Manufacturing method of hose connector - Google Patents

Description

  The present invention relates to a copper tube for hose connection in which a nipple portion having a concavo-convex shape is formed at a tip portion of a copper tube, and a hose connector in which a hose is connected to the copper tube for hose connection using a socket.

  As a metal tube for hose connection, which is not limited to a copper tube, for example, one described in Patent Document 1 is known. A nipple portion (insert portion) having an uneven shape is integrally formed at the distal end portion of the metal tube in order to firmly attach the hose to the outer peripheral surface thereof. Then, with the hose connected to the nipple portion of the metal pipe, the connecting portion is caulked and fixed with a socket (sleeve) to form a hose connector (pipe joint) in which the metal pipe, hose and socket are integrated. ing.

JP 2012-117558 A

  By the way, when the use of the hose connector is a water supply pipe, a hot water supply pipe, or the like, a copper pipe that is relatively resistant to corrosion among metal pipes is used. However, since copper is generally softer than iron, aluminum, etc., even if the nipple part as in Patent Document 1 is formed integrally with a copper pipe, sufficient strength cannot be obtained, and as a water supply pipe or hot water supply pipe May not be able to withstand the use of Therefore, conventionally, for example, a method of separately preparing a nipple member made of brass harder than copper, and connecting a hose using a copper tube on one side of the nipple member and a socket on the other side has been taken. .

  However, from the viewpoint of cost reduction, it is desirable to eliminate the nipple member and form the nipple part integrally with the copper pipe. In order to realize this, it is important to sufficiently ensure the strength of the nipple portion in the copper pipe. However, although Patent Document 1 describes using copper as a material for the metal tube as an example, it does not mention how to secure the strength of the nipple portion of the copper tube in that case.

  This invention is made | formed in view of the said situation, Comprising: The objective is to ensure the intensity | strength of a nipple part enough in the copper pipe for hose in which the nipple part which has an uneven | corrugated shape was formed.

  The present invention is a copper tube for connecting a hose in which a nipple portion having a concavo-convex shape is formed at a tip portion of a copper tube, wherein the nipple portion is formed by a rolling process, and the nipple portion is formed by the rolling process. The region including is reduced in diameter as a whole.

  According to the present invention, by forming the nipple portion by rolling, the nipple portion is subjected to plastic deformation, and the strength of the nipple portion can be increased. Further, unlike the cutting process, the rolling process is advantageous in that it does not involve a reduction in wall thickness. Furthermore, in the present invention, not only the nipple portion is formed by rolling processing, but also the entire area of the nipple portion is further reduced by reducing the diameter of the entire region including the nipple portion by rolling processing. be able to. As described above, according to the copper tube for hose connection according to the present invention, it is possible to sufficiently ensure the strength of the nipple portion.

It is a partial cross section figure of the copper pipe for hose connection concerning this invention, and a hose connector.

  Hereinafter, embodiments of a copper tube for hose connection and a hose connector according to the present invention will be described with reference to the drawings. The copper pipe for hose connection and the hose connection body according to the present invention are resistant to corrosion by using a copper pipe, and can be suitably used as a water supply pipe or a hot water supply pipe. Of course, it can also be used for applications.

  Fig. 1a is a diagram showing the hose connection copper tube 1 as a single unit, Fig. 1b is a diagram showing a state where the socket 30 is attached to the hose connection copper tube 1, and Fig. 1c is a hose connection copper tube. 1 is a view showing a hose connector 100 in which a hose 40 is caulked and fixed to a socket 30 by a socket 30. FIG. In any of the drawings, the upper half shows a cross section along the axial direction of the copper tube 1 for hose connection, and the lower half shows the appearance.

  The copper pipe 1 for hose connection is processed into the shape shown in FIG. A by rolling the copper pipe 10. Specifically, by using a rolling die (not shown), the nipple portion 11 having a concavo-convex shape is formed at the tip of the copper tube 10 by performing the rolling process on the rolling processing range R of the copper tube 10. At the same time, an annular engagement groove 15 is formed on the outer peripheral surface on the opposite end side (left side in FIG. 1) from the nipple portion 11.

  Further, when the rolling process is performed, the rolling process range R of the copper tube 10 is pressed toward the center in the radial direction by the rolling die, so that the rolling process range R is reduced in diameter as a whole, and the copper tube The outer diameter is smaller than that of the 10 tube portion (the portion on the opposite end side from the rolling processing range R). In other words, the axial direction region (rolling processing range R) of the copper pipe 10 including the nipple portion 11 and the engagement groove 15 is reduced in diameter as a whole by rolling processing.

  The nipple portion 11 has a concavo-convex shape having a total of six annular grooves 12 and 13 and an annular convex portion 14 formed therebetween. Of these, the five annular grooves 12 are grooves for preventing the hose 40 from being pulled out by causing the hose 40 to bite in during caulking and fixing described later. On the other hand, the annular groove 13 located second from the tip side is a groove for mounting the O-ring 20 (see FIG. B). However, the specific configuration of the nipple portion 11 is not limited to this, and the numbers and dimensions of the annular grooves 12 and 13 and the annular convex portion 14 may be changed. In FIGS. 1b and 1c, the reference numerals of the annular protrusions 14 are omitted in order to avoid complication of the drawing.

  As shown in FIG. B, the engaging groove 15 formed on the opposite end side from the nipple portion 11 is a groove for fitting and positioning the end portion of the socket 30 used for caulking and fixing. The socket 30 has a cylindrical shape, and one end thereof is a donut-shaped engagement portion 31 having an opening in the center when viewed from the axial direction. By inserting the hose connecting copper tube 1 into the socket 30 from the opening of the engaging portion 31 and fitting the inner peripheral edge of the engaging portion 31 into the engaging groove 15, the socket 30 is connected to the hose connecting copper tube 1. Is positioned.

  While the engaging portion 31 of the socket 30 is fitted in the engaging groove 15, the hose 40 (see FIG. C) is fitted on the nipple portion 11 with the O-ring 20 attached to the annular groove 13. Subsequently, by using a caulking jig (not shown) to press the hose 40 against the nipple portion 11, the socket 30 is formed with three caulking portions 32 in the axial direction so that the hose 40 is a copper tube for hose connection. 1 is fixed by caulking. In order to prevent the hose connection copper tube 1 from being greatly deformed during caulking, the socket 30 is caulked with a core (not shown) such as iron inserted into the hose connection copper tube 1. It is done.

  In this way, as shown in FIG. C, a hose connector 100 in which the hose 40 is caulked and fixed to the copper tube 1 for hose connection by the socket 30 is produced. In the present embodiment, the three caulking portions 32 in the axial direction are positions facing the nipple portion 11. By doing so, each caulking portion 32 is preferable because the hose 40 is strongly pushed into the annular groove 12 of the nipple portion 11 and the hose 40 is difficult to come off. Note that it is possible to freely set the number of places where the socket 30 is caulked and the position where the socket 30 is caulked. However, from the viewpoint of preventing the hose 40 from coming off, it is preferable that at least one caulking portion 32 is formed at a position facing the nipple portion 11.

  Here, when producing the hose connector 100, as described above, the socket 30 is caulked with the unillustrated core inserted into the hose connection copper tube 1. At this time, since the center core is slightly smaller than the inner diameter of the hose connection copper tube 1, there is a slight gap between the inner peripheral surface of the hose connection copper tube 1 and the outer periphery surface of the center core. Therefore, even if the socket 30 is caulked with the center core inserted, the nipple portion 11 is slightly deformed by caulking pressure.

  Specifically, when caulking is performed at three caulking portions 32 in the axial direction as in this embodiment, the vicinity of the central portion 16 facing the central caulking portion 32 where the caulking pressure is most likely to act is radially inward. The nipple portion 11 is deformed so as to be recessed. On the other hand, at the front end portion 17 of the nipple portion 11, the applied caulking pressure is smaller than that at the central portion 16 and is a free end, so that not only radial deformation but also axial deformation is possible. Yes. For this reason, the radial deformation at the distal end portion 17 becomes smaller as the distance from the central portion 16 increases. As a result, the outer diameter of the distal end portion 17 increases toward the distal end side. However, the outer diameter of the tip portion 17 is equal to or smaller than the outer diameter of the rolled (reduced diameter) straight portion 18 outside the socket 30. The tip portion 17 may have a constant inclination or a curved shape. Hereinafter, the distal end portion 17 is referred to as a “prevention portion 17”.

  By forming the retaining portion 17 at the distal end portion of the nipple portion 11, the hose 40 becomes difficult to move in the disconnecting direction, and the effect of preventing the hose 40 from being disconnected can be further improved. Such a retaining portion 17 is formed because copper is a material that is relatively soft and easily deformed. In other words, if the nipple portion 11 is too hard, deformation such that the central portion 16 is recessed is less likely to occur in the first place, and the retaining portion 17 whose diameter increases toward the distal end side cannot be obtained appropriately. However, if the nipple portion 11 is too soft, the strength becomes insufficient, and the function as a water supply pipe or a hot water supply pipe may not be achieved. Therefore, in this embodiment, the necessary strength is ensured together with other measures by setting the thickness of the copper tube 10 to about 0.6 to 1.0 mm, more preferably about 0.7 to 0.8 mm. In addition, the retaining portion 17 can be easily formed using the softness of copper.

(performance test)
In order to verify whether the hose connector 100 configured as described above has sufficient performance as a water supply hose, various performance tests were performed. As a comparative example, a conventional hose connector is provided in which a brass nipple member is prepared as a separate member, and a hose is connected to one end of the nipple member using a copper tube and a socket on the other end. The copper pipe, hose and socket used in the comparative example are the same as those used in the examples of the present invention.

Table 1 shows main specifications of Examples and Comparative Examples of the present invention. As for the hardness, as is apparent from the comparison between the hardness of the unprocessed portion of the example and the hardness of the comparative example, copper is inherently much harder than brass. However, by rolling the copper tube, the hardness is significantly increased, although it still does not reach brass, and the nipple part formed by the rolling process has sufficient strength. It is guessed. Further, the hardness of the annular protrusion 14 (see FIG. 1a) is slightly (about 10 HV) smaller than the hardness of the annular groove 12 of the embodiment which is greatly plastically deformed during the rolling process. . Due to this difference in hardness, a slight difference also occurs in deformation during caulking and the retaining portion 17 can be formed more easily and smoothly. In addition, as for the dimension of the copper tube 10 in a present Example, an outer diameter is 9.52 mm and thickness is 0.7 mm.

Table 2 shows test conditions, target performance, and test results of each performance test.

  In the water pressure test, normal temperature water is poured into the hose connector, and a test is performed to determine whether or not there is water leakage in a state where a pressure of 1.72 MPa is applied for 5 minutes. When the test was performed three times in the examples, no water leakage was observed in any of the tests, and it was shown that the performance was equivalent to that of the comparative example.

  In the burst test, normal temperature water is injected into the hose connector, and a test is performed to determine whether or not there is water leakage in a state where a pressure of 2.94 MPa is applied for 5 minutes. When the test was performed three times in the examples, no water leakage was observed in any of the tests, and it was shown that the performance was equivalent to that of the comparative example. Furthermore, when the pressure at which the hose connector was ruptured was measured, it was shown that the example has a burst strength equivalent to that of the comparative example in any of the three tests.

  In the tensile test, the state in which the hose connector is pulled with 981 N is continued for 5 minutes, and then the above-described water pressure test is performed to check whether there is any water leakage. Also in this test, no abnormality was found in the examples, and it was shown that the performance was equivalent to that of the comparative example.

  The durability test is a test for examining whether or not the normal temperature water is poured into the hose connector and the pressure can be withstood 100,000 times between 0 MPa and 1.72 MPa. In the Examples, it was shown that even if the pressurization was repeated up to 500,000 times, which greatly exceeded 100,000 times, water leakage did not occur, and the performance was equivalent to that of the Comparative Example.

  From the above test results, it was shown that according to the hose connector 100 of the present embodiment, performance equivalent to that of the comparative example using the brass nipple member harder than copper can be secured. That is, it has been shown that by using the hose connection copper tube 1 integrally formed with the nipple portion 11, it is possible to provide the hose connector 100 that is not inferior to the conventional product while realizing the reduction in the number of parts and the cost.

(effect)
As described above, according to this embodiment, by forming the nipple portion 11 of the copper tube 1 for hose connection by rolling, the nipple portion 11 is subjected to plastic deformation, and the strength of the nipple portion 11 is increased. Can be improved. Further, unlike the cutting process, the rolling process is advantageous in that it does not involve a reduction in wall thickness. Furthermore, in the copper tube 1 for hose connection, not only the nipple portion 11 is formed by rolling, but also the axial region including the nipple portion 11 is entirely reduced in diameter by rolling, so that the nipple portion 11 Further improvement in strength can be realized throughout. As described above, according to the copper tube 1 for hose connection of the present embodiment, it is possible to sufficiently ensure the strength of the nipple portion 11. Further, since the diameter of the copper tube 10 is reduced simultaneously with the rolling process when forming the nipple portion 11, it is also preferable in that the strength can be improved without increasing the number of processing steps.

  Moreover, in the copper tube 1 for hose connection of this embodiment, the axial direction area | region including the engaging groove 15 in addition to the nipple part 11 is diameter-reduced entirely by the rolling process. For this reason, the strength in the vicinity of the engagement groove 15 can also be improved, and deformation of the hose connection copper tube 1 can be suppressed when the socket 30 is attached.

  Further, in the hose connector 100 of the present embodiment, a retaining portion 17 whose outer diameter increases toward the distal end side is formed at the distal end portion of the nipple portion 11. For this reason, it can suppress effectively that the hose 40 crimped and fixed to the copper tube 1 for hose connection comes off from the nipple part 11. FIG.

  Further, in the hose connector 100 of the present embodiment, an O-ring 20 (annular seal member) is provided on the outer peripheral surface of the retaining portion 17. Thus, the O-ring 20 is more compressed between the nipple part 11 and the hose 40 by providing the O-ring 20 in the retaining part 17 whose outer diameter is larger than the central part 16 of the nipple part 11. Thus, the sealing effect can be improved. Further, by providing the O-ring 20 in the retaining portion 17 formed at the tip of the nipple portion 11, it is possible to prevent fluid from entering between the hose connecting copper tube 1 and the hose 40 and penetrating deeply. .

  Moreover, in the conventional product which provided the nipple member separately, since the copper pipe was connected to the one end side of a nipple member and a hose was connected to the other end side, it was necessary to provide a sealing member in each connection part. However, according to the copper tube 1 for hose connection of the present embodiment, it is only necessary to provide a seal member at the connection portion between the nipple portion 11 and the hose 40, so that the number of seal members can be reduced. .

  In addition, this invention is not limited to the said embodiment, Unless it deviates from the meaning, it is possible to combine the element of the said embodiment suitably, or to add a various change.

1: Copper tube for hose connection 10: Copper tube 11: Nipple portion 13: Annular groove 15: Engaging groove 17: Stopping portion (tip portion)
20: O-ring (seal member)
30: Socket 31: Engagement part (end part)
40: Hose 100: Hose connector

Claims (3)

By rolling , a nipple portion having a concavo-convex shape is formed at the tip of a copper tube having a thickness of 0.6 to 1.0 mm, and the entire region including the nipple portion of the copper tube is reduced in diameter. The rolling process,
A hose connection step of fitting the end of the socket into an engagement groove formed on the outer peripheral surface of the copper tube on the opposite end side of the nipple portion, and externally fitting a hose to the nipple portion;
A caulking step for caulking and fixing the hose to the copper pipe by forming a caulking portion on the socket so as to press the hose fitted on the nipple portion against the nipple portion;
With
The caulking step forms a retaining portion having the concavo-convex shape, the outer diameter of which increases toward the distal end side at the distal end portion of the nipple portion.
A method for manufacturing a hose connector , characterized in that : Oite before Symbol rolling process, the production method of the hose connection of claim 1, wherein causing the nipple portion added overall diameter region which also includes the engaging groove. In the hose connection step, an outer peripheral surface of the portion where the retaining portion is formed by the caulking step, the annular groove forming the uneven shape formed by the rolling step, and the hose on the nipple portion The method for manufacturing a hose connector according to claim 1 or 2 , wherein an annular seal member is attached before external fitting .