JPH05118484A - Slip joint for duct - Google Patents

Abstract

PURPOSE:To enable two duct joints with continuous irregularities on an inner wall to be easily connected, using a member of simple constitution. CONSTITUTION:Both ends of a cylindrical body are used as insertion sections 20a for coupling to a duct, and coupling projections 22 having a larger outer diameter than other sections are formed at the predetermined positions of the insertion sections 20a. In addition, the sections 22 and the vicinity thereof are so formed as to have elasticity for flexing inward due to external pressure. The coupling projections 22 are engaged with an irregular section inside the duct, upon coupling the insertion sections 20a and, therefore, good coupling state can be maintained between a slip joint and a duct only via a coupling work. Furthermore, a seal material is fitted to both ends of the center large diameter section of the slip joint and, therefore, high sealing quality can be kept between the joint and the duct, thereby ensuring the high sealing quality of a joint section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duct insertion joint for jointing two ducts, and more particularly to a duct insertion joint for jointing ducts whose inner side walls are formed in a concavo-convex shape continuous in the longitudinal direction. Is.

[0002]

2. Description of the Related Art A flexible duct made of a metal such as stainless steel or aluminum so as to be deformable is generally widely used as a pipe for passing water or the like.

In such a flexible duct,
It may be necessary to join the ends of the two flexible ducts, such as for length adjustment.

FIGS. 3 (A) and 3 (B) are explanatory views showing a general example of the work for connecting the above flexible ducts. As shown in FIG. 3 (A), first, in the extension direction. The ends of the two flexible ducts 10 and 12 having continuous outer walls with concavities and convexities are made to face each other, and both ends of the cylindrical insertion joint 14 are inserted into the respective end openings. The cylindrical insertion joint 14 is formed in a cylindrical shape, and left and right end portions thereof are formed as insertion portions 14a. Then, a central large-diameter portion 14b having a larger diameter than the other portions is provided substantially at the central portion. Then, the insertion portions 14a at both ends are inserted into the openings of the flexible ducts 10 and 12, respectively.

FIG. 1B shows a state after the above-mentioned inserting operation is performed, and the flexible ducts 10 and 12 are shown.
The end portion of the insertion portion 14a up to the central large diameter portion 14b.
Is being inserted.

Next, the outer periphery of the flexible ducts 10 and 12 in the inserted portion of the insertion portion 14a is clamped and fixed by the clamps 16a and 16b. That is, the flexible ducts 10 and 12 are tightened between the outer peripheral surface of the insertion portion 14a of the cylindrical insertion joint 14 and the tightening fittings 16a and 16b, thereby jointing.

Further, Japanese Utility Model Laid-Open No. 58-177686 discloses a structure for making a complete seal connection of a bellows type duct in an inboard fan device or the like. In this structure, packing and a plurality of patch locks are provided at the joints of the ducts to be jointed, and the ducts are jointed in a sealed state.

[0008]

However, in the above-mentioned conventional joint structure, the fastening metal fitting 16 is provided on the duct portion where the insertion portion 14a of the cylindrical insertion joint 14 is inserted, that is, on the outer periphery of both the flexible ducts 10 and 12.
It was necessary to attach a and 16b. Further, in this mounting work, in order to make the coupled state between the ducts more stable, it was necessary to tighten the flexible ducts 10 and 12 to such an extent that the shapes of the flexible ducts 10 and 12 were deformed to some extent. In this way, the fastening metal fittings 16 are attached at two places, and the flexible duct 10 is provided with a stronger fastening force.
Since it was necessary to deform 12 and 12, the work was complicated.

Further, in the technique disclosed in Japanese Utility Model Laid-Open No. 58-177686, it is necessary to attach a packing for a shield and further install a patch lock or a hook, which is used in a general building or the like. It was not suitable for flexible duct joints. That is, the technology disclosed above considers the sealing of a duct used in a ship, and requires a large number of members as described above. It could not be used in joints.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a duct insertion joint capable of stably performing joints between ducts with a simple structure and a simple operation. It is in.

[0011]

That is, the invention according to claim 1 is to connect the ducts having continuous unevenness formed in the inner wall and in the extending direction thereof to each other, so that the open ends of the two ducts are connected. In a tubular duct insertion joint to be inserted into a tubular body, a central large-diameter portion having an outer diameter larger than that of the other portion is formed substantially at the central portion in the longitudinal direction, and the tubular body is inserted from both ends of the central large-diameter portion. The part up to both ends is the insertion part to be inserted, and a locking projection having an outer diameter larger than that of the other part is provided at an intermediate position of the insertion part. It is formed with a predetermined elasticity so that it is bent inward by a pressure from one side, and when the insertion of the insertion portion into the duct is completed, the locking projection is locked to the uneven portion of the inner wall of the duct. It is characterized by

On the other hand, the invention according to claim 2 is premised on the invention according to claim 1, and at both ends of the central large-diameter portion, a sealing material for ensuring a hermeticity between the ends of the duct. Is provided.

Further, in each of the above inventions, since the cylindrical insertion joint is used in a flexible duct or the like, it is preferable to use a metal having excellent corrosion resistance such as stainless steel or zinc iron plate. Further, regarding the elasticity of the locking protrusion and the vicinity thereof, when the insertion portion is inserted into the duct opening end, it can be bent to such an extent that the insertion work is not difficult and when the insertion work is completed, The locking projection is locked to the uneven portion of the duct and is set to have an appropriate elasticity so that it cannot be easily disengaged by the pulling operation.

[0014]

According to the first aspect of the present invention, when the insertion portion of the duct insertion joint is inserted from the duct opening end side, the locking projection formed at an intermediate position of the insertion portion is continuously formed on the inner wall of the duct. It is pushed inward while colliding with the uneven portion that is being formed. That is, the head of the locking projection collides with the continuous projections and depressions of the duct, and the locking projection bends inwardly and moves in the insertion direction. Then, when the insertion of the predetermined insertion length is completed, the head portion of the locking projection is housed and engaged in the recess of the corresponding duct.

As a result, the insertion portion of the insertion joint and the duct are brought into engagement with each other by the locking projection of the insertion joint. Therefore, since the engaging operation with the duct is performed on both ends of the duct insertion joint, the two ducts are jointed via the duct insertion joint.

As described above, a good duct connection state can be obtained only by inserting the insertion portion without using various fixing members such as the conventional fastening members.

Further, according to the second aspect of the present invention, since the tip end portion of the duct inserted into the insertion portion is sealed by the seal material at both end portions of the central large diameter portion, the duct and the duct insertion joint are connected. It is possible to more reliably ensure the airtightness between them, and thereby it is possible to effectively prevent leakage of the flower such as water at the joint portion of the duct.

[0018]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an explanatory view showing the overall construction of the duct insertion joint according to the embodiment.
Has the same overall cylindrical shape as the conventional insertion joint 14 used in the joint structure shown in FIG.
Similarly, the central large-diameter portion 20b is formed substantially at the center in the longitudinal direction.

The locking projection 22, which is a characteristic component of the present invention, is formed at an intermediate position between the left and right insertion portions 20a, and has a chevron shape having a larger diameter than the other portions around the outer periphery of the insertion portion 20a. Is formed by forming a protrusion. The locking projection 22 is configured to bend inward of the tubular body due to pressure from the outside.
In this embodiment, the entire tubular body is made of stainless steel having a predetermined thickness, so that the elasticity of the locking projection 22 is ensured so as to be appropriately bent during the insertion operation into the duct.

Further, in the present embodiment, the central large diameter portion 20b.
The sealing material 24 is installed at both ends, that is, at the boundary between the insertion portion 20a and the central large diameter portion 20b. The sealing material 24 is formed of, for example, an elastic member such as rubber and has a diameter slightly larger than the outer diameter of the insertion portion 20a.

Next, the joint operation between the ducts using the duct insertion joint 20 according to the above embodiment will be described.

First, as shown in FIG. 2A, a flexible duct to which the insertion portion 20a of the duct insertion joint 20 is to be joined, that is, a wall portion of which has a wavy uneven shape in the longitudinal direction. Flexible duct 1
The operation (arrow 100) of inserting into the opening end 10a of 0 is performed.

At this time, as shown in FIG. 3B, the locking projection 22 of the insertion portion 20a has the protruding tip 2 which is the head thereof.
2a collides with the protrusion on the inner side of the flexible duct 10 and bends inward. That is, as described above, the portion in the vicinity of the locking projection 22 is formed to have a predetermined elasticity, and the protruding tip 22 which is the head thereof.
It is pushed inward by the collision of a.

The state in which the insertion portion 20a is inserted in this way and the insertion operation is completed is shown in FIG. As shown, the locking projections 22 engage the flexible duct 10
It is in a state of being engaged with the inner side of the protruding portion protruding outward from the wavy uneven portion. As described above, at the position where the locking projection 22 is formed, the flexible duct 10 has the central large-diameter portion 20.
It is set so as to be located at the portion of the convex portion projecting outward of the flexible duct 10 when pushed to the portion b. Further, also on the flexible duct 10 side, the cutting position of the opening end is appropriately set so that the locking projection 22 is not displaced.

When the insertion portion 20a is completely inserted, the opening end of the flexible duct 10 has the sealing material 2
It is in a state of being in close contact with No. 4. As a result, the inside and outside of the flexible duct 10 can be completely sealed, and a good joined state can be obtained.

The same operation is also performed with the other flexible duct for the insertion portion 20a on the left side of the drawing of the duct insertion joint 20.

As described above, according to the above-described embodiment, the coupling with the flexible duct can be performed only by the operation of inserting the insertion portion 20a into the opening end of the flexible duct, and the coupling state is locked. The protrusion 22 is stabilized by the engaged state, and the sealing material 24 also ensures hermeticity. In this way, it is possible to obtain a good connection between the duct insertion joint 20 and each flexible duct, and as a result, the joint of the two flexible ducts can be performed more easily and reliably.

The present invention is not limited to the above embodiments, but various modifications can be made within the scope of the invention. For example, the length of the insertion portion 20a in the extension direction can be variously set, set longer than that of the embodiment, and the locking projection 22 is not limited to one as in the above embodiment. Instead, a plurality of flexible ducts can be formed according to the uneven positions.

[0030]

As described above, according to the duct insertion joint of the first aspect, the insertion joint and the duct can be jointed with a simple structure and a simple operation, and another fixing member is used. It is possible to obtain a good coupling state between the ducts via the insertion joint without.

Further, according to the duct insertion joint of the second aspect, the airtightness between the insertion joint and the duct can be made more reliable, and the occurrence of the gap in the joint portion can be effectively prevented. it can.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an overall configuration of an embodiment.

2A, 2B, and 2C are explanatory views showing a joint operation of a duct by the duct insertion joint according to the embodiment.

3A and 3B are explanatory views showing an example of a duct joint structure using a conventional duct insertion joint.

[Explanation of symbols]

 20 Duct Insert Joint 20a Insertion Part 20b Central Large Diameter Part 22 Locking Protrusion 24 Sealing Material

Claims (2)

[Claims] 1. A tubular duct insertion joint to be inserted into the open ends of two ducts for connecting ducts having continuous irregularities formed on the inner wall and in the extending direction thereof to each other. A central large-diameter portion having an outer diameter larger than that of the other portion is formed substantially at the central portion in the direction, and a portion from both ends of the central large-diameter portion to both ends of the tubular body is the insertion portion to be inserted, A locking protrusion having an outer diameter larger than that of the other part is provided at an intermediate position of the insertion portion, and the locking protrusion and a portion in the vicinity thereof have a predetermined elasticity so as to be bent inward by a pressure from the outside. The insertion joint for a duct, characterized in that the locking projection is locked to the uneven portion of the inner wall of the duct when the insertion of the insertion section into the duct is completed. 2. The duct insertion joint according to claim 1, wherein both ends of the central large-diameter portion are provided with sealing materials for ensuring hermeticity with the ends of the duct. An insertion joint for ducts.