JP2001130237A - Duct for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a duct for vehicle capable of realizing a low cost and a light weight while applying a bedewing prevention countermeasure and a noise countermeasure. SOLUTION: A cylindrical duct is formed by a foamed substance and a duct end portion is bent and superposed onto a duct body 1 side. The bent portion 3 is fixed to the duct body 2 by an engagement means 5 to form an engagement portion J with a connection port 71 of a connection partner side 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duct for a vehicle used in an air conditioning system of a vehicle, and more particularly to a duct for a vehicle suitable for an air conditioning system path from an air conditioner unit to a passenger compartment.

[0002]

2. Description of the Related Art Cylindrical air ducts are often used in the air conditioning system path (from the air conditioner unit to the passenger compartment) of an automobile, and a blow molded product mainly using a polypropylene resin material or the like is used.

[0003]

However, since a polypropylene resin or the like is used for the material of the air duct, dew condensation tends to occur. Therefore, as a countermeasure against dew condensation, conventionally, it has been necessary to attach a urethane foam sheet 91 which is a dew condensation preventing material to one or both sides of the air duct 8 as shown in FIG. In addition to the sealing material 92 on the connecting portion 81, the material must be adhered to the dew condensation preventing material 91, and the material cost and the adhering work cost are increased. In addition, there has been a demand for a reduction in the weight of recent automobiles, and it has been difficult to meet this demand. Furthermore, there was a problem that the noise of the air conditioner blower propagated through the duct and was heard in the passenger compartment.

[0004] The present invention solves the above problems,
An object of the present invention is to provide a vehicle duct that achieves low cost and light weight while taking measures to prevent dew condensation and noise.

[0005]

In order to achieve the above object,
The gist of the invention described in claim 1 is that a tubular duct is formed of a foam, the duct end is folded back so as to overlap the duct main body side, and the folded portion is fixed to the duct main body by locking means. And forming a fitting portion with the connection port on the connection partner side. According to a second aspect of the present invention, in the vehicle duct according to the first aspect, a groove is formed in a boundary region between the folded portion and the duct main body on a front surface or a back surface of the duct.

According to the first aspect of the present invention, when the vehicle duct is formed of the foam itself, it is possible to reduce the weight and effectively deal with sound insulation and heat insulation. When the end of the duct is folded back on the duct body side and the folded part is fixed to the duct body with a locking means, the fitting with the connection port on the connection partner side, which is a drawback caused by forming only the foam, is provided. Part rigidity can be obtained. According to the second aspect of the present invention, when a groove is formed in the boundary region between the folded portion and the duct main body, the concave portion of the groove allows the folded portion to be smoothly inverted to the duct main body and to be superposed on the duct main body smoothly.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a vehicle duct according to the present invention will be described in detail. 1 to 6 show an embodiment of the vehicle duct of the present invention. FIG. 1 is a partially enlarged perspective view of (a) a duct in an expanded state, and (b) is a portion of a regular vehicle duct after assembly. FIG. 2 is an enlarged perspective view of FIG.
FIG. 3 is a view taken along the line A in FIG. 1, and FIG.
FIG. 6 is a view showing another aspect of the vehicle duct.

The vehicle duct is obtained by processing a tubular duct formed of a foam. The cylindrical duct is manufactured as follows, for example. A plate-shaped foam sheet made of a foamed polypropylene resin or the like is prepared, and this is formed into a half-split cylinder 1 by vacuum forming (or pressure forming). The half-split cylinder 1 has a substantially equal cross-sectional shape in the longitudinal direction, and is provided with a half-split portion 11 and a flange portion 12 extending horizontally outward from a side edge of the half-split portion. In the vacuum forming process, the two halved cylinders 1 are opposed to each other so as to provide the cylinder of the duct flow path O, and the flanges 12 and 12 are fusion-bonded to each other, and the flange 12 protruding outward in the radial direction is formed. The duct is fixed as shown in FIG. The completed duct also has a substantially equal cross-sectional shape in the longitudinal direction. Symbol m is a fusion bonding portion. In the present embodiment, a pair of half cylinders 1 constituting a duct for a vehicle are simultaneously molded,
Further, the flange portion 12 is joined and fixed by fusing using sheet heating. Alternatively, a method may be adopted in which a pair of half-split cylinders 1 are separately formed, and a flange portion 12 is fused in a later step to form a tubular vehicle duct.

In the duct thus formed, a groove 4 having a U-shaped cross section (may be V-shaped, etc.) divides the duct into a folded portion 3 and a duct main body 2 on the duct surface side. In other words, a groove 4 is formed in a boundary region between the folded portion 3 and the duct main body 2. The grooves 4 may be formed together during the molding process or may be formed by post-processing. The groove 4 may be formed on the back surface of the duct or on both sides, but it is preferable to provide the groove 4 in the entire area in the circumferential direction of the duct. The reason is that the turning point is determined by the groove 4, and the turning portion 3 can be easily overlapped on the duct main body 2. The appearance of the folded end portion is also improved.

The folded portion 3 is folded at the cylindrical end portion of a predetermined length L from the end of the duct so as to be superimposed on the duct main body side, and as shown in FIG. Of the vehicle duct) is formed. Since the duct is formed of foam as described above and has a good cushioning property and elasticity, it is possible to relatively easily fold the end of the duct toward the duct body 2 (toward the duct main body 20) by making use of this characteristic. It is possible (open arrow in FIG. 1). The length L of the folded portion 3 is appropriately determined depending on the specifications, the shape of the connection port 71 of the connection partner 7, and the like. The folded portion 3 and the flange portion 12 in the duct body portion 21 on which the folded portion 3 is overlapped are trimmed and cut as necessary.

When the folded portion 3 is overlaid on the duct main body 2 side, the duct main body portion 21 inside the duct main body 2 is tightened, and the folded portion 3 also fits tightly on the duct main body 2. (FIG. 2). The duct has almost the same cross-sectional shape in the longitudinal direction (except for the groove 4).
This is because their diameters are almost the same. In a duct formed of a foam that is relatively easily deformed on the folded portion 3 on the duct main body 2 side, only the folded portion 3 is hardened due to bubble compression by tightening, and rigidity is increased. Folded portion 3 and duct body portion 2 on which it is overlapped
In No. 1, as shown in FIG. 2, the thickness thereof is reduced by the compression amount ε due to the tightening.

The foam sheet as a raw material used in the vehicle duct of the present invention is the above-mentioned foamed polypropylene sheet or foamed polyethylene sheet, and has a foaming ratio of 1
It is about 5 to 30 times. Here, a 25-fold expanded product is used as the expansion ratio of a foamed polypropylene sheet. Also,
The thickness of the foam sheet is 5 mm, while the thickness of the conventional blow-molded product made of polypropylene (FIG. 7) is about 1.5 mm.
Use the one with the same thickness (again, use the one with this thickness).

Further, in the present invention, the folded portion 3 is fixed to the duct main body 2 by the locking means 5 to form a fitting portion J with the connection port 71 of the connection partner 7. Thus, the folded portion 3 is fixed by the locking means 5 so that the folded portion 3 does not shift or become unstable.
The configuration is such that the function as the fitting portion J, which is literally a duct connection portion, can be exhibited while maintaining a predetermined fitting strength and sealing property.

In this embodiment, the locking means 5 is stapled at a predetermined pitch as shown in FIG. FIG.
As shown in (b), at the place where the stapler needle 5a is present, the folded portion 3 made of foam and the duct body 2 are tightened and dented and become hard. However, when it is used as the fitting portion J, the folded portion 3 and the duct body 2 at a position slightly away from the stapler needle 5a have predetermined elasticity, cushioning property, etc., and there is no problem in securing the sealing property. Become.

FIGS. 3 and 4 show another embodiment of a vehicle duct in which a fixing portion 5b is formed as a locking means 5 by fusion. After the folded portion 3 is folded on the duct body 2 so as to be superimposed on the duct body 2, the fusion terminals 6 are pressed against the folded portion 3 at a predetermined pitch in the circumferential direction of the folded portion 3 to fuse and join the folded portion 3 and the duct body 2. The fixing part 5b to be formed is formed. The fusion method is based on vibration, ultrasonic waves, high frequency, hot plate, or the like.

FIGS. 5 and 6 show another embodiment of a vehicle duct in which a fitting type locking means 5 is employed. First, holes 23 are opened at a predetermined pitch in the circumferential direction of the duct of the folded portion 3, and the folded portion 3 is folded back on the duct main body 2 so as to be overlapped. Next, a part of the duct main body 2 is made to protrude from the hole 23 by inserting the jig in the direction of the white arrow in FIG. Thereafter, the fusion terminal 6 or the like is applied to the protruding portion to form a stopper 5c for integrating the folded portion 3 and the duct main body 2.

The thus constructed duct for a vehicle has a thickness of about 5 mm, which is about 1.5 mm thick than the conventional blow-molded product made of PP, but is formed of a foam alone, so that it is lightweight. Can be achieved. The weight can be reduced by about 80% as compared with the conventional product shown in FIG. In addition, the duct for this vehicle is made of the foam itself, which is excellent in heat insulation and sound insulation.
It is effective for noise control. Actually, the blowing noise inside the duct was reduced, and the noise caused by interference with the counterpart outside the duct was reduced. The vehicle duct formed solely of the foam is provided with the dew condensation preventing material 91 and the sealing material 9
2 can be manufactured at a lower cost than a conventional product that had to be attached. When manufacturing from a foam sheet, it is relatively easy to manufacture, and it is possible to manufacture a thick vehicle duct with excellent heat insulation and sound insulation at low cost.

On the other hand, in a vehicle duct made of a foam body alone, there is a possibility that the foam may be deformed due to weakness of the waist of the foam body or the like. For example, deformation can be suppressed. In addition, although there is a problem that a desired rigidity cannot be obtained at the connection port 71 of the connection partner 7 with a cylindrical duct made of a mere foam, the present invention provides the folded portion 3 and the locking means 5.
Then, the folded portion 3 is fixed to the duct main body 2 to form a fitting portion J to solve the problem. In the fitting portion J, the air bubbles of the foam can be contracted by tightening the duct main body portion 21 in which the folded portion 3 is disposed below, and the rigidity can be increased. Since the fitting portion J is originally made of a foam, the sealing member 92 is separately provided.
Need not be prepared, and thus the connectable fitting portion J that can satisfy the required mechanical strength and sealability of the connection port 71 of the connection partner 7 can be completed. The fitting part J
The folded portion 3 is fixed to the duct body portion 2 by the locking means 5.
Since it is fixed to 1, it does not lose its shape. There is no need for separate parts for increasing rigidity (resin molded products, wires, pressed products, etc.). Further, when a groove 4 is formed in the boundary area between the folded portion 3 and the duct body 2, the folded point of the folded portion 3 is determined by the groove 4, and the recess of the groove 4 causes the folded portion 3 to be placed on the duct body portion 21. Stacking becomes easy.

It should be noted that the present invention is not limited to the embodiment described above, but can be variously modified within the scope of the present invention depending on the purpose and application. The shape, size, thickness, material, number and the like of the duct body 2, the folded portion 3, the groove 4, the locking means 5, and the like can be appropriately selected according to the application. In the embodiment, the tubular duct is formed from the foam sheet. However, the duct may be a vehicle duct in which the tubular duct is formed at once and the end thereof is folded to form the fitting portion J.

[0020]

As described above, the vehicle duct of the present invention has the following features.
It can be manufactured at low cost while improving heat insulation and sound insulation, and exhibits excellent effects such as light weight.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial enlarged perspective view of an embodiment of a duct for a vehicle according to the present invention, wherein (a) is a partially enlarged perspective view of a duct in an expanded state, and (b) is a partially enlarged perspective view of a regular duct for a vehicle after assembly. .

2A is a view taken along line AA of FIG. 1, and FIG.
FIG. 3 is a view taken along line BB of FIG.

FIG. 3 is a partially enlarged perspective view of a vehicle duct different from that of FIG. 1;

FIG. 4 is an explanatory cross-sectional view showing a pattern forming a fixing portion of FIG. 3;

FIG. 5 is a partially enlarged perspective view of a vehicle duct different from those of FIGS. 1 and 3;

FIG. 6 is an explanatory sectional view showing a pattern for forming the stopper of FIG. 5;

FIG. 7 is an explanatory perspective view of a conventional technique.

[Explanation of symbols]

 2 Duct body 3 Folded part 4 Groove 5 Locking means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroshi Suzuki 3-36 Imaikecho, Anjo-shi, Aichi F-term (reference) 3L011 BL02 in Inoac Corporation Anjo Office

Claims (2)

[Claims] 1. A tubular duct is formed from a foam, and the duct end is folded back so as to overlap the duct body side, and
A duct for a vehicle, wherein the folded portion is fixed to a duct main body by locking means to form a fitting portion with a connection port on a connection partner side. 2. The vehicle duct according to claim 1, wherein a groove is formed in a boundary area between the folded portion and the duct body on a front surface or a back surface of the duct.