JP3735958B2 - Pipe fitting cap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pipe joint cap made of resin, for example, which is attached to an opening end of a joint part of a refrigerant pipe when the refrigerant pipe of a vehicle air conditioner is assembled.
[0002]
[Prior art]
In general, in a vehicle air conditioner, a space in which a case containing an evaporator or the like is arranged is separated from an engine room in which a traveling engine is arranged by a body. Therefore, the evaporator and other equipment are connected by passing the joint of the refrigerant pipe connected to the evaporator through the through-hole formed in the body and connecting to the joint of the refrigerant pipe connected to other equipment. Is done.
[0003]
By the way, the joint part of the refrigerant pipe connected to the evaporator should not be contaminated with foreign matter such as moisture, dust or dirt before it is connected to the joint part of the refrigerant pipe connected to other equipment. It is covered with a pipe joint cap made of resin or the like.
As such a cap for a pipe joint, one having a structure as shown in Japanese Utility Model Laid-Open No. 6-76109 is known. In the above publication, a plurality of ribs formed inside are press-contacted to the outer peripheral surface of the joint portion of the pipe so that the outer periphery of the cap body that sandwiches the pipe has a tapered shape, thereby smoothly inserting into the grommet. Is possible.
[0004]
[Problems to be solved by the invention]
Incidentally, it is generally known that a molded article made of a resin has a property of shrinking at a low temperature. Therefore, when the outside air temperature is low, such as in winter, the cap for a pipe joint shown in the above publication contracts in the inner circumferential direction. Therefore, as in the above publication, a pipe joint cap that clamps the joint portion of the refrigerant pipe by pressing the rib formed inside the cap body against the joint portion of the refrigerant pipe is generated at a low temperature. Since the contraction force of the cap acts locally, the force for tightening the joint portion of the refrigerant pipe by each rib is increased. As a result, when the temperature is low, the force required to remove the cap from the joint portion of the refrigerant pipe is increased, which makes it difficult to remove the cap.
[0005]
Accordingly, the present invention has been made in view of the above points, and an object thereof is to provide a cap for a pipe joint having a structure for preventing an increase in the force required to remove the pipe from the pipe at a low temperature. It is.
[0006]
[Means for Solving the Problems]
In general, a molded article made of a resin has a property of shrinking at a low temperature, and it is known that the degree of shrinkage increases as the wall thickness increases. Therefore, in order to solve the above-mentioned problem, according to the invention of claim 1, the fixing portion (5) for fixing the joint portion (103) of the pipe (100) is made thin so that the fixing portion at a low temperature is obtained. The shrinkage force can be suppressed. In addition, the fixed portion has a cylindrical shape, and the cylindrical inner surface presses the substantially entire circumference of the outer peripheral surface of the joint portion to fix the joint portion. Therefore, the shrinkage force of the cap (1) at a low temperature is It acts over almost the entire circumference of the outer peripheral surface and is dispersed. Therefore, when the cap contracts at a low temperature or the like, it is possible to prevent an increase in the force required to remove the cap from the pipe. Furthermore, since the rib is provided between the outer peripheral portion and the fixed portion, deformation of the cap body can be prevented when penetrating the grommet.
[0007]
By the way, since the outer diameter of the pipe portion provided with the hexagonal portion (104) and the insulator (105) is larger than the outer diameter of the joining portion, a step is formed between the joining portion and the hexagonal portion. However, according to the invention of claim 1, since the cap body (2) has a double structure having the outer peripheral portion (4) and a fixed portion formed on the joint portion side of the outer peripheral portion. The fixed portion and the outer peripheral portion can be formed in different shapes. That is, even if the fixing portion is thin, the outer peripheral portion is not a shape along the outer periphery of the pipe, that is, a shape in which a step is formed between the outer peripheral surface of the cap body and the skirt portion (3). It can be made into the shape where the outer periphery spreads gradually toward the skirt part side. As a result, it is possible to obtain a shape that allows the pipe to which the cap is attached to smoothly penetrate the grommet, the through hole, or the like while making the fixing portion thin.
[0008]
Furthermore, according to the invention of claim 2, by making the outer peripheral portion (4) into a substantially dome shape, the cap (1) can be formed into a shape that allows the cap (1) to pass through the grommet, the through hole, etc. more smoothly. it can.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
Although not shown, the case in which an evaporator or the like is housed is arranged in a space separated from an engine room in which a traveling engine is arranged by a body. The pipe 100 connected to the evaporator passes through a through hole formed in the body and a grommet made of rubber or the like engaged with the periphery of the through hole, and is drawn out to the engine room side. By connecting the piping 100 drawn to the engine room side to piping connected to other equipment (for example, a compressor), the evaporator and the other equipment are connected.
[0010]
An open end 101 of the pipe 100 connected to the evaporator is a joint portion 102 connected to a pipe connected to another device. An end portion of the joint portion 102 is a joint portion 103, and a male screw is formed on the outer peripheral surface thereof. The portion of the joint 102 that is closer to the evaporator than the joint 103, that is, the position farther from the opening end 101 than the joint 103 is formed in a hexagonal nut shape having an outer diameter larger than the outer diameter of the joint 103. It is a hexagonal portion 104 that fixes the jig when connecting the joint portion 103 to another pipe 100.
[0011]
Furthermore, an insulator 105 made of foamed rubber (for example, ethylene propylene rubber) is attached to the evaporator side of the hexagonal portion 104, that is, the portion of the pipe 100 that is located farther from the opening end 101 than the hexagonal portion 104, The space between the case and the grommet and the pipe 100 is sealed to prevent leakage of air from the case and entry of foreign matters such as water from the engine room into the case. The outer diameter of the insulator 105 is approximately equal to the outer diameter of the hexagonal portion 104.
[0012]
By the way, the open end 101 of the pipe 100 having such a structure is flexible before it is connected to a pipe connected to other equipment so that foreign substances such as water and dust do not enter the evaporator. It is in a state of being covered with a pipe joint cap (hereinafter referred to as a cap) 1 made of a resin (for example, polyethylene). Hereinafter, the structure of the cap 1 will be described.
[0013]
The cap 1 has a substantially cylindrical shape with one end closed and the other end opened, and is attached to the pipe 100 so that the open end 101 of the pipe 100 is closed by the closed end. The closed end side of the cap 1 is a cap body 2 that covers the joint portion 103 provided at the open end 101 of the pipe 100, and the open end 101 side is a hexagonal portion so that the insulator 105 does not turn over when passing through the grommet. The skirt portion 3 covers the 104 and the insulator 105.
[0014]
The cap body 2 includes an outer peripheral portion 4 that is in sliding contact with the grommet when passing through the grommet attached to the body in order to connect the pipe 100 to another pipe, and the joint portion 103 side, that is, the inner side. And a fixing portion 5 for fixing the joint portion 103, and has a double structure.
The outer peripheral portion 4 gradually expands from the front end portion (the end portion on the opening end 101 side when the cap 1 is attached to the pipe 100, the closed end of the cap body 2) 6 toward the skirt portion 3. And has a substantially dome shape. Therefore, it is formed from the front end portion 6 to the skirt portion 3 so as to be a smooth curved surface having no step. A shaft 7 extending in the axial direction of the cap main body 2 is provided at the center of the tip end portion 6 of the cap main body 2, and a substantially hemispherical handle 8 that is gripped when attaching to and detaching from the pipe 100 is provided at the front end. Is provided.
[0015]
Inside the cap body 2, a substantially cylindrical surface having an inner diameter slightly smaller than the outer diameter of the joint portion 103 of the pipe 100 and having the same axial direction as the cap body 2 is formed as the fixing portion 5. .
Between the fixed portion 5 and the outer peripheral portion 4, a plurality of ribs 9 extending in a direction substantially perpendicular to the outer peripheral surface of the fixed portion 5 and the inner peripheral surface of the outer peripheral portion 4 are formed. Further, a step 10 is formed on the inner wall surface of the cap body 2 at a position closer to the tip 6 than the fixed portion 5. When the cap 1 is attached to the pipe 100, the step 10 The piping 100 is positioned by the contact of the opening end 101 of the joint portion 103.
[0016]
In addition, the thickness of the fixing | fixed part 5, the outer peripheral part 4, and the skirt part 3 is 0.5-0.7 mm, and is thin. The fixed portion 5, the outer peripheral portion 4, and the skirt portion 3 are formed by integral molding.
Next, the operation of this embodiment will be described.
The cap 1 is pushed in such a direction that the joint portion 103 is covered by the cap body 2 and is attached to the pipe 100 until the opening end 101 of the joint portion 103 comes into contact with the step 10 formed inside the cap body 2. . Since the inner diameter of the fixing portion 5 is slightly smaller than the outer diameter of the joint portion 103 of the pipe 100, the joint portion 103 is inserted into the cap body 2 while being elastically deformed so as to expand the fixing portion 5. Therefore, the joint portion 103 is clamped and fixed by the force with which the fixing portion 5 tries to return to the original shape. At this time, since the fixing portion 5 has a cylindrical surface shape, the fixing portion 5 is press-contacted over almost the entire outer peripheral surface of the bonding portion 103 to fix the bonding portion 103.
[0017]
The pipe 100 thus attached with the cap 1 passes through the grommet and is drawn out to the engine room side. At this time, the outer peripheral portion 4 of the cap main body 2 slidably contacting the grommet is connected to the skirt portion 3 side from the tip portion 6. Since the outer periphery of the pipe 100 has a substantially dome shape and is formed to have a smooth curved surface without a step from the tip 6 to the skirt 3, the piping 100 can be connected to the grommet without being caught by the grommet. Can be penetrated.
[0018]
By the way, the resin generally has a property of shrinking when the temperature is lowered. Furthermore, it is known that a resin molded product having a substantially cylindrical shape as shown in the present embodiment contracts in the direction of the central axis, and the extent of the contraction increases as the thickness of the resin molded product increases.
In the present embodiment, the thickness of the fixing portion 5 of the cap body 2 is 0.5 to 0.7 mm, which is thinner than the thickness (1 to 3 mm) of the conventional cap. Therefore, the shrinkage | contraction of the cap 1 at the time of low temperature, such as winter, can be suppressed.
[0019]
The cap body 2 has a double structure in which the outer peripheral portion 4 that is in sliding contact with the grommet when the pipe 100 to which the cap 1 is attached is passed through the grommet and the fixing portion 5 that fixes the joint portion 103 are separately formed. Therefore, even if the fixing portion 5 is thin, the shape of the outer peripheral portion 4 can be the above-described shape, and when the pipe 100 is passed through the grommet, it is difficult to be caught by the grommet. it can.
[0020]
In addition, since the fixing portion 5 is formed so as to be in pressure contact over substantially the entire circumference of the outer peripheral surface of the joint portion 103, the contraction force of the cap 1 at a low temperature acts on substantially the entire circumference of the outer peripheral surface of the joint portion 103. , Distributed.
Therefore, when the cap 1 contracts at a low temperature, it is possible to prevent an increase in force required to remove the cap 1 from the pipe 100.
[0021]
Moreover, since the rib 9 is provided between the outer peripheral part 4 and the fixing | fixed part 5, when making the piping 100 which attached the cap 1 penetrate the grommet, it can prevent that the cap 1 deform | transforms. it can.
Moreover, in this Embodiment, not only the fixing | fixed part 5, but the outer peripheral part 4 and the skirt part 3 are formed so that it may become thin, and the cap 1 whole is formed so that it may become thin. Therefore, the expansion and contraction of the cap 1 due to the temperature change of the outside air can be suppressed.
[0022]
In the embodiment described above, the shape of the cap body is a substantially dome shape. However, the shape may be any shape as long as the outer periphery gradually widens from the tip to the skirt. It is not limited.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of a pipe joint cap according to the present invention.
FIG. 2 is a view of the pipe joint cap according to the present invention as viewed from the opening end of the pipe joint cap.
FIG. 3 is a partial cross-sectional view showing a state in which a pipe joint cap according to the present invention is attached to a pipe.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe joint cap 2 Cap main body 3 Skirt part 4 Outer peripheral part 5 Fixing part 6 The front-end | tip part 100 which is the edge part which becomes the opening end side of piping of a cap main body 101 Pipe 101 Open end 102 Joint part 103 Joint part 104 Hexagon part 105 Insulator

Claims (3)

A cap main body that covers the joint portion of the joint portion provided at the opening end of the pipe, and is provided at a portion of the joint portion that is located farther from the opening end than the joint portion, and has a larger outer shape than the joint portion. A pipe joint cap having a hexagonal part and a skirt part covering an insulator provided on the outer periphery of the pipe part located farther from the opening end than the hexagonal part,
The cap body is made of resin,
An outer peripheral portion formed so that an outer periphery thereof gradually expands from an end which is the opening end side of the pipe to the skirt portion side when attached to the pipe, and a cylindrical shape, the cylinder An inner surface is press-contacted over substantially the entire circumference of the outer peripheral surface of the joint portion, and includes a thin-walled fixing portion that fixes the joint portion, and the fixing portion is formed to be closer to the joint portion than the outer peripheral portion. A pipe joint cap , wherein a rib is provided between the fixed portion and the outer peripheral portion .   2. The pipe joint cap according to claim 1, wherein the outer peripheral portion has a substantially dome formation.   The said rib is provided with two or more, and is extended in the direction substantially perpendicular | vertical with respect to the outer peripheral surface of a fixing | fixed part, and the inner peripheral surface of an outer peripheral part, The pipe joint cap of Claim 1 or Claim 2 characterized by the above-mentioned.

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