JP2001153443A - Air-conditioning duct - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning duct in which a flange of a metallic sheet duct is reinforced. SOLUTION: A flange 2 is formed by outwardly bending a common plate protruding from the end of each side 1a of a duct 1, with respect to an axis of the duct 1 and afterward bending it back to the position of an outer side surface of the duct 1. Thus, the flange 2 has a double structure of the common plate, which can reinforce the intensity of the flange 2 which is weak in an air-conditioning duct produced by a flange processing method. The outer periphery of the edge of the duct 1 is provided with steps 3 for stopping the ends of the bent back common plates, respectively, thereby fixing the ends of the readily bent back common plates to the end of the outer periphery of the duct 1. Portions along the outer periphery of the duct 1, which are provided to the end of the bent back common plates, are subjected to spot welding to reinforce the end portion of the duct 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an air conditioning duct made of sheet metal.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 5 and 6, a flange portion b formed of a common plate projecting from each side of a duct a is formed at an end of a duct a made of sheet metal and having a polygonal cross section. Air-conditioning ducts (by the common plate flange method) are known. In FIG. 5, c indicates a clip for connecting the ducts a with the flange portions b and b held therebetween.

[0003]

The air-conditioning duct according to this method has an advantage that the seal between the duct and the flange can be simplified since there is no joint between the duct and the flange. However, in consideration of workability, workability (lightness) at the time of work, etc., a relatively thin metal plate (sheet thickness 0.5 mm to 1.6 mm)
However, the strength of the flange portion a where the stress is concentrated is insufficient, although the strength is high enough to withstand the pressure of the fluid (air conditioning air or ventilation air) flowing inside due to the use of a galvanized iron plate of a certain degree. There is a possibility that the flange part a may be inconvenient, such as sagging, and it is recognized that even when a zinc iron plate having a thickness of 0.8 mm is used, only a duct having an internal pressure of about 500 Pa and a length of about 1500 mm is formed. It is not currently being done. The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an air-conditioning duct in which the strength of a flange portion of the air-conditioning duct by a common plate flange method is increased.

[0004]

According to the first aspect of the present invention, a flange made of a common plate protruding from each side of the duct is provided at an end of a duct made of sheet metal and having a polygonal cross section. In the air-conditioning duct provided, by folding the common plate protruding from the end of each side of the duct to the outside of the duct and then back to the outer surface position of the duct to form the flange portion, Since it is composed of a heavy co-plate, the strength of the fragile flange portion in the air-conditioning duct by the flange method can be increased.

According to a second aspect of the present invention, in the first aspect of the present invention, a step is provided on the outer periphery of the end of the duct to lock the leading end of the folded back plate, thereby simplifying the operation. The front end of the common plate folded back to can be fixed to the outer periphery of the end of the duct.

According to a third aspect of the present invention, in the first aspect of the present invention, a portion is provided along the outer periphery of the duct at the end of the folded back plate, and the portion is spot-welded to the duct. Thus, the end of the duct can be reinforced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. Reference numeral 1 denotes a duct made of sheet metal and having a polygonal cross section. The duct 1 has, at both ends thereof, a flange portion 2 formed of a common plate projecting from each side.

The duct 1 shown in the figure is formed by bending a rectangular metal plate into a rectangular cross section and bending both side edges into a rectangular cross section. The flange 2 is formed by bending a common plate protruding from an edge of each side of the duct 1 outwardly of the duct 1 and then back to the outer surface position of the duct 1.

This will be described with reference to the drawings. The common plate is projected from most of the edges except both sides of each side 1a, and the common plate is bent outward of the duct 1. To form a first bent portion 2a, bend the distal end side of the first bent portion 2a in the length direction of the duct 1 and then turn it back to form an edge 2b, and further form a first rising portion at the distal end side. 2a to return to the outside of the duct 1 and return to the second bent portion 2c.
The flange 2 has a width by the edge 2b, and the projection 2b-1 formed at the end of the edge 2b functions as a clip retaining portion to be described later.

FIGS. 1 to 3 show an example in which a recess slightly wider than the width of a common plate is provided at an end of a duct 1 at a position corresponding to the common plate, and a step 3 formed at the end of the hollow is provided. Then, the tip of the second bent portion 2c is locked. In the duct 1 thus obtained, the tip of the second bent portion 2c is locked and fixed to the step portion 3, and the work such as spot welding for fixing the tip of the second bent portion 2c to the duct 1 can be omitted. , The production becomes simpler, and the inner diameter 50 which was not recognized by
A duct having a duct length of 0 Pa or more and a duct length of 1500 mm or more can be obtained.

In each of the corners of the duct 1, there is a portion without the flange 2 formed by the above-described structure. Therefore, a corner fitting 2d was attached to this portion. The corner fitting 2d includes a rectangular cover 2d-1 that covers a space formed between the adjacent flanges 2 and 2, and the cover 2d.
legs 2d-2, 2d protruding from two adjacent sides of d-1
2d-2, 2d-2.
Is inserted between the first bent portion 2a and the second bent portion 2c of the flange portion 2 and fixed.

In FIGS. 1 to 3, the second bent portion 2c is fixed by locking the tip of the second bent portion 2c to the step portion 3. As shown in FIG. Bending part 2c
A portion 2e may be provided at the front end of the duct 1 and attached to the outside of the duct 1, and the portion 2e may be fixed to the duct 1 by spot welding.
There is an advantage that both ends can be reinforced. The connection between the air-conditioning ducts is performed by attaching a packing between the flange portions 2 and 2 as in the conventional example and using the same clip as in the conventional example.

The above-described one is a duct 1 having a rectangular cross section.
However, the present invention is not limited to this, and may be a pentagon or other polygons. Further, when a rectangular duct is formed, the above-described one is formed by bending a single metal plate to have a rectangular cross section. However, this may be formed by assembling a metal plate forming one side of the duct 1 with a metal plate bent into a U-shaped cross section in which three sides of the duct 1 are connected, and further, two adjacent sides of the duct are connected. It may be formed by combining two metal plates bent into an L-shaped cross section, or may be formed by combining four metal plates constituting each side of the duct.

[0014]

According to the invention as set forth in claim 1 of the present application, the common plate protruding from the end of each side of the duct is bent outward of the duct, and then folded back to the position of the outer surface of the duct. By configuring the flange portion, it is possible to increase the strength of the fragile flange portion 2 in the air conditioning duct by the co-plate flange method, and to withstand a sufficiently high pressure even with the same metal plate as before for air conditioning. A duct can be obtained.

According to the second aspect of the present invention, a stepped portion is provided on the outer periphery of the end of the duct to lock the tip of the folded back plate, so that the folded back plate is easily folded. Can be fixed to the outer periphery of the end of the duct, thereby simplifying the production operation.

According to a third aspect of the present invention, a portion along the outer periphery of the duct is provided at the end of the folded back plate, and the portion is spot-welded to the duct, so that not only the flange portion but also the duct can be formed. The ends can also be reinforced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a main part of FIG. 1 before a corner fitting is assembled.

FIG. 3 is a sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a cutaway side view showing another embodiment.

FIG. 5 is a perspective view showing a conventional example.

FIG. 6 is an enlarged sectional view taken along the line VI-VI in FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Air-conditioning duct 2 Flange part 3
Step

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[Procedure amendment]

[Submission date] December 14, 1999 (1999.12.
14)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

[0004]

According to the first aspect of the present invention, a flange made of a common plate protruding from each side of the duct is provided at an end of a duct made of sheet metal and having a polygonal cross section. In the air-conditioning duct provided, by folding the common plate protruding from the end of each side of the duct to the outside of the duct and then back to the outer surface position of the duct to form the flange portion, because it is composed of heavy co plate, in the air conditioning duct by co plate off <br/> flange method, it is possible to increase the strength of the flange portion is vulnerable.

Claims (3)

[Claims] 1. An air-conditioning duct having a flange formed of a common plate protruding from each side of a duct at an end of a duct made of a sheet metal and having a polygonal cross section, and protruding from an end of each side of the duct. An air conditioning duct, wherein the flange is formed by folding the common plate to the outside of the duct and then back to the outside surface position of the duct. 2. The air-conditioning duct according to claim 1, wherein a step is provided on an outer periphery of an end portion of the duct to lock a leading end of the folded back plate. 3. The air-conditioning duct according to claim 1, wherein a portion is provided along the outer periphery of the duct at the end of the folded back plate, and the portion is spot-welded to the outer periphery of the duct.