JP2003322277A - Joint for pipe connection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint for pipe connection for enhancing the working efficiency. <P>SOLUTION: This joint D for pipe connection to connect an upper pipe disposed above a through hole 1a in a wall body 1 to a lower pipe 2 disposed below the through hole 1a or advancing into the through hole from a lower part thereof comprises a cylindrical upper connection part 5 which is disposed on a tip of the upper pipe and has a lower end part 4 with a male screw part 3 formed on an outer circumferential surface thereof, a lower connection part 7 which is disposed on a tip of the lower pipe 2 and has a small diameter part 6 with an upper end part thereof inserted in the lower end part 4 of the upper connection part 5, and a cap nut 9 which is moved along the small diameter part 6 in the axial direction thereof, and has a female screw part 8 screwed to the male screw part 3. A drop preventive means 12 to prevent the cap nut 9 from being dropped downward is provided on a lower side of the small diameter part 6. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pipe connecting joint.

[0002]

2. Description of the Related Art As shown in FIG. 4, an upper pipe (not shown) arranged above a through hole 1a penetrating a wall body 1,
It is provided at the tip of the upper pipe as a conventional pipe connecting joint for connecting the lower pipe 2 that is arranged below the through hole 1a or that enters the through hole 1a from below. , And is cylindrical and has an external thread 3 on its outer peripheral surface.
An upper connecting portion 5 having a lower end portion 4 provided with a lower diameter portion 6 and a small diameter portion 6 provided at the tip of the lower pipe and the upper end portion of which is inserted into the lower end portion 4 of the upper connecting portion 5. Some include a side connection portion 7'and a cap nut 9 having an internal thread portion 8 that moves along the small diameter portion 6 in the axial direction thereof and is screwed to the external thread portion 3.

In the above pipe connecting joint, the small diameter portion 6 of the lower connecting portion 7'is provided inside the lower end portion 4 of the upper connecting portion 5.
The upper pipe and the lower pipe 2 can be connected by screwing the cap nut 9 and the male screw portion 3 of the upper connecting portion 5 in the inserted state.

[0004]

However, the above-described conventional pipe connecting joint has the following problems. That is, when performing the above-mentioned connecting work, first, before inserting the small diameter portion 6 of the lower connecting portion 7 ′ into the through hole 1 a, the cap nut 9 is fixed in advance near the upper end portion of the small diameter portion 6 with gum tape or the like. Then, in this state, the lower connecting portion 7 is inserted into the through hole 1a and projected above the through hole 1a.
Subsequently, the small diameter portion 6 is inserted into the lower end portion 4 of the upper connecting portion 5, and finally, the gum tape is removed, and then the through hole 1
The cap nut 9 exposed above a is rotated and screwed to the male screw portion 3.

If the cap nut 9 falls along the small diameter portion 6 in the through hole 1a or below the through hole 1a during the above connecting work, particularly when the gum tape is removed, It is necessary to push (or pull up) the cap nut 9 again above the through hole 1a using a tool or the like, and when there is no space around the through hole 1a, push up as described above ( Since the work of pulling up was not possible, the connection work had to be redone from the beginning (before inserting the lower connection portion 7 into the through hole 1a), and in any case, the work efficiency was remarkably reduced. There was a problem.

The present invention has been made in consideration of the above-mentioned problems, and an object thereof is to provide a pipe connecting joint capable of increasing work efficiency.

[0007]

In order to achieve the above object, a pipe connecting joint according to the present invention includes an upper pipe arranged above a through hole penetrating a wall body and a lower pipe arranged below the through hole. Or a pipe connecting joint for connecting a lower pipe entering from the lower side into the through hole, which is provided at the tip of the upper pipe and is cylindrical and has an external thread on its outer peripheral surface. An upper connection portion having a lower end portion formed with a portion, a lower connection portion having a small diameter portion provided at the tip of the lower pipe, and the upper end portion of which is inserted into the lower end portion of the upper connection portion, A cap nut having an internal thread portion that moves in the axial direction along the small diameter portion and that is screwed to the male screw portion, and prevents the cap nut from falling below the small diameter portion. A fall prevention means is provided for this purpose (claim 1).

According to the present invention having the above-mentioned structure, it is possible to provide a pipe connecting joint which can increase working efficiency. That is, in the above-mentioned conventional pipe connection joint, before inserting the lower connection portion into the through hole, it is necessary to fix the cap nut with gum tape or the like, and even if it is fixed with gum tape in this way. , There is a possibility that the cap nut will fall when it is removed, whereas in the present invention having the above-mentioned configuration, before inserting the lower connection portion into the through hole, The work of fixing with gum tape etc. is unnecessary, and by installing the above-mentioned fall prevention means at an appropriate position, it is possible to automatically insert the lower connection part into the through hole and project it above it. In addition, the cap nut can be configured to be exposed above the through hole.

Further, the fall prevention means may be formed by a large-diameter portion connected to the small-diameter portion (claim 2). In the case of the pipe connecting joint having such a configuration, when the lower connecting portion is formed by cutting one columnar member, the small diameter portion should be a part and the rest should be a large diameter portion. As a result, the amount of cutting is reduced, which in turn makes it possible to save the time and cost required for forming by cutting.

Further, it may be used for connecting the pipes constituting the analyzer (claim 3), and a diluting section for diluting the exhaust gas from the engine and leading the diluted exhaust gas to the downstream side thereof, and this diluting section. In an engine exhaust gas analyzer provided on the upstream side of the heating unit for heating the exhaust gas introduced from the engine to the dilution unit, and the analysis unit for analyzing the diluted exhaust gas, the connection of the pipes constituting the heating unit It may be used for (Claim 4).

For example, in an analyzer such as an engine exhaust gas analyzer, not only when using the finished product,
There are many cases in which one or more pipes are placed in the housing and the pipes are connected from the outside to the pipes inside the housing at the prototype stage or at the time of testing. In the case where the external pipe is connected from the bottom side of the housing, there is a problem that the work efficiency for connecting the pipe is significantly reduced due to the reason described above. By using the pipe connecting joint, since the above problems can be solved, the use of the pipe connecting joint of the present invention for connecting the pipes constituting the analyzer such as the engine exhaust gas analyzer means that the pipes are connected. It is extremely effective in that it can improve the work efficiency of, and by extension, it enables efficient trial manufacture and testing of the above-mentioned analyzer, and can reduce the time and burden required for development. That.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view schematically showing the structure of a pipe connecting joint D according to the first embodiment of the present invention. The pipe connection joint D is used, for example, for connecting pipes that constitute an analyzer for performing various analyses, and more specifically, a casing (FIG. 1) having a single or a plurality of pipes (not shown) inside thereof. (Not shown) and another pipe (not shown) arranged outside the casing, the pipe arranged in the casing is provided with another pipe from the outside of the casing. Used to connect tubing.

In the present embodiment, the pipe connecting joint D comprises a diluting portion (not shown) for diluting exhaust gas from an engine (not shown) and leading the diluted exhaust gas to the downstream side thereof. A heating unit (not shown) provided on the upstream side of the dilution unit for heating the exhaust gas introduced from the engine to the dilution unit, and an analysis unit (not shown) for analyzing the diluted exhaust gas.
It is used to connect the pipes that form an engine exhaust gas analyzer (not shown) provided with, and more specifically, one pipe (not shown) arranged in the housing of the engine exhaust gas analyzer. It is used for connection with another pipe arranged outside the housing, and either one or both of the one pipe and the other pipe constitute the heating unit.

The pipe connecting joint D includes, for example, an upper pipe (not shown) arranged above a through hole 1a penetrating a wall body 1 such as a bottom wall of an analyzer housing, and It is provided below the through hole 1a or for connecting to the lower pipe 2 which enters the through hole 1a from below, and is provided at the tip of the upper pipe and has a cylindrical shape. Lower end 4 with external thread 3 formed on its outer peripheral surface
An upper connecting portion 5 having a lower diameter, and a lower connecting portion 7 having a small diameter portion 6 provided at the tip of the lower pipe 2 and having an upper end inserted into the lower end 4 of the upper connecting portion 5.
A cap nut 9 having an internal thread portion 8 that moves in the axial direction along the small diameter portion 6 and is screwed to the external thread portion 3 is provided.

The lower end portion 4 of the upper connecting portion 5 has a tapered surface portion 10 inside the lower end, which becomes wider toward the lower side.

The lower connecting portion 7 has a nut portion 7a on the lower end side thereof, and a large diameter portion 11 is continuously provided below the small diameter portion 6, and the large diameter portion 11 is provided. The upper end of the is a fall prevention means 12 for preventing the cap nut 9 from falling downward. The nut portion 7a
Is formed between the small diameter portion 6 and the nut portion 7a.

Further, a ferrule 13 is provided on the upper portion of the small diameter portion 6. The ferrule 13 is formed in a substantially ring shape, and the outer peripheral surface thereof has a tapered surface whose diameter increases toward the lower side.

The cap nut 9 has a narrowed portion 9a which is continuously provided below the female screw portion 8 and which is in a state substantially along the outer surface of the small diameter portion 6.

In the pipe connecting joint D having the above structure, the cap nut 9 is previously attached to the small diameter portion 6 of the lower connecting portion 7.
After that, the ferrule 13 is fitted into the small diameter portion 6, and then the female screw portion 8 of the cap nut 9 is screwed onto the male screw portion 3 of the upper connecting portion 5 to fix the ferrule 13 to the small diameter portion 6. . That is, the ferrule 13 is sandwiched between the narrowed portion 9a of the cap nut 9 and the tapered surface portion 10 of the lower end portion 4 by screwing the male screw portion 3 and the female screw portion 8, and the ferrule 13 is caulked and fixed to the small diameter portion 6. You can do it.

Then, with respect to the upper connecting portion 5 provided in the upper pipe, the lower connecting portion 7 provided in the lower pipe 2
In order to connect, the lower connecting portion 7 is inserted into the through hole 1a from below and the through hole 1a is inserted, and the small diameter portion 6 is placed inside the lower end portion 4 of the upper connecting portion 5. insert. At this time, the ferrule 13 is in contact with the tapered surface portion 10 of the lower end portion 4.

After the above operation, the cap nut 9 held by the drop preventing means 12 and exposed above the through hole 1a is lifted, and its female screw portion 8 is screwed to the male screw portion 3 of the lower end portion 4. Simply, the upper connecting part 5 and the lower connecting part 7
Connection with the upper pipe and the lower pipe 2
The connection with will also be completed.

In the pipe connecting joint D having the above structure, the cap nut 9 is held by the drop preventing means 12 so that the lower connecting portion 7 is projected above the through hole 1a. Then, the cap nut 9 is automatically exposed above the through hole 1a, and even if the worker releases the cap nut 9 once grasped by a mistake such as sliding his hand. Since it does not fall inside or below the through hole 1a, the working efficiency can be increased.

As shown in FIG. 2 (C), the lower connecting portion 7'used in the conventional pipe connecting joint has the small diameter portion 6 except for the nut portion 7a. On the other hand, the lower connecting portion 7 of the present invention has the large diameter portion 11 between the small diameter portion 6 and the nut portion 7a, as shown in FIG. 7,7 '
When the hexagonal prism-shaped member 14 as shown in FIG. 2 (A) is formed by cutting, the lower connecting portion 7 has a lower hexagonal prism shape than the lower connecting portion 7 '. The amount of cutting 14 is reduced, which in turn makes it possible to save the time and cost required for forming by cutting.

In the above embodiment, the large diameter portion 11
Is formed from the small diameter portion 6 to the nut portion 7a, but the present invention is not limited to such a configuration. For example, only the upper portion of the large diameter portion 11 is left and the other portion is the small diameter portion 6. You may comprise so that it may become the same diameter.

FIG. 3 is an explanatory view schematically showing the construction of the pipe connecting joint D ₂ according to the second embodiment of the present invention. The members having the same structure as those shown in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. The pipe connecting joint D ₂ of the second embodiment is different from the pipe connecting joint D of the first embodiment in that the large diameter portion 11 of the lower connecting portion 7 is not provided and the large diameter portion 11 is provided. Is different in that a spring member 15 is provided as an alternative to.

In the pipe connecting joint D _{2 having the} above structure, the spring member 15 serves as the fall prevention means 12 in the first embodiment, and in this respect, it is the same as the first embodiment. The effect can be obtained. Further, it becomes possible to use the lower connecting portion 7'used in the conventional pipe connecting joint as it is.

[0027]

According to the present invention having the above-mentioned structure, it is possible to provide a pipe connecting joint capable of increasing working efficiency.

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing a configuration of a pipe connecting joint according to a first embodiment of the present invention.

2 (A) and 2 (B) are perspective views schematically showing the structure of the lower connecting portion before and after processing in the above embodiment, and FIG. 2 (C) is used for a conventional pipe connecting joint. It is a perspective view which shows roughly the structure of the lower side connection part which was carried out.

FIG. 3 is an explanatory view schematically showing a configuration of a pipe connecting joint according to a second embodiment of the present invention.

FIG. 4 is an explanatory view schematically showing a configuration of a conventional pipe connecting joint.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wall body, 1a ... Through hole, 2 ... Lower piping, 3 ... Male screw part, 4 ... Lower end part, 5 ... Upper connection part, 6 ... Small diameter part, 7 ...
Lower connection part, 8 ... Female screw part, 9 ... Cap nut, 12 ... Fall prevention means, D ... Pipe connection joint.

Claims (4)

[Claims] 1. An upper pipe arranged above a through hole penetrating a wall body and a lower pipe arranged below the through hole or entering into the through hole from below. A pipe connection joint for, which is provided at the tip of the upper pipe, has an upper connecting portion having a lower end portion which is cylindrical and has an external thread formed on its outer peripheral surface, and at the tip of the lower pipe. A lower connecting portion which is provided and has a small diameter portion into which the upper end portion is inserted in the lower end portion of the upper connecting portion, and which moves in the axial direction along the small diameter portion and is screwed onto the male screw portion. A pipe connecting joint, comprising: a cap nut having a female screw portion, and a fall prevention means for preventing the cap nut from falling downwardly provided on the lower side of the small diameter portion. 2. The pipe connecting joint according to claim 1, wherein the drop prevention means is formed by a large-diameter portion continuous with the small-diameter portion. 3. The pipe connecting joint according to claim 1, which is used for connecting pipes constituting an analyzer. 4. A dilution section for diluting exhaust gas from an engine and leading the diluted exhaust gas to a downstream side thereof, and heating for heating the exhaust gas introduced from the engine to the dilution section, which is provided on the upstream side of the dilution section. A pipe connecting joint according to claim 1 or 2, which is used for connecting pipes forming the heating unit in an engine exhaust gas analyzer including a section and an analysis unit for analyzing the diluted exhaust gas.