JPH0749273B2 - Magnetic contact type vibration control sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetically-adhesive type vibration damping sheet applied for vibration damping (including vibration damping) of a vertical surface portion of a vehicle vibration portion.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a magnetically attached damping sheet 22 is used on the vertical surface portion of, for example, a quarter panel 11 of an automobile. The vibration damping sheet 22 contains asphalt as a main component, inorganic fibers, and a filler,
Iron powder having a high residual magnetism (usually ferrite is used) is kneaded to form a sheet having a predetermined thickness, and the iron powder is magnetized to obtain magnetic powder 4A. The damping sheet 22 is arranged on the steel plate of the quarter panel 11 and heat-sealed. In this case, until the asphalt portion of the vibration damping sheet 22 oozes out and adhesive force is generated, the quarter panel 1
A large amount of magnetic powder 4A is mixed in order to hold the vertical surface portion of No. 1 by magnetic attraction.

[0003]

As described above, the conventional magnetically-adhesive type vibration damping sheet contains a large amount of magnetic powder, so that the vibration damping sheet itself has a large specific gravity. Also,
Since the ferrite used as the iron powder is an expensive material, the magnetic-type vibration damping sheet has the drawback of being expensive.

Therefore, an object of the present invention is to solve the above drawbacks, and it is an object of the present invention to provide a magnetic and vibration damping sheet which is lightweight and inexpensive.

[0005]

In order to solve the above-mentioned problems, the present invention is a vibration-damping sheet for magnetically holding and heat-sealing the magnetic powder on the vertical surface of a vehicle vibration part, and a magnetic powder of 40-80 is used. %
It is characterized in that the compounded thin hot melt layer is adhered to one surface on the heat fusion side of the vibration damping sheet layer.

The magnetic powder is a magnetized iron powder such as ferrite. The hot melt layer is composed of a thin layer of, for example, 400 μm in which magnetic powder is mixed with hot melt (component). A hot melt having a softening point lower than that of the vibration damping sheet layer is selected and used. For example, EV
A thermoplastic synthetic resin such as A (ethylene vinyl acetate copolymer), polyethylene or polypropylene, or a rubber elastomer may be used alone or in combination. If necessary, a tackifier such as petroleum resin may be added to the hot melt.

The damping sheet layer is mainly composed of bituminous material,
If necessary, an inorganic filler such as talc, clay, calcium carbonate, etc., and / or a fiber material such as asbestos, glass wool, etc. may be mixed therein, and for example, 2.0
mm layers. The damping sheet layer has a softening point according to the temperature condition of the heat fusion furnace.

The magnetically-adhesive damping sheet of the present invention can be widely applied to prevent vibration of the vertical surface of a vehicle vibration part such as a quarter panel, a dash panel or a wheel house of a vehicle.

[0009]

The damping sheet is magnetically held on the vertical surface by the magnetic powder in the hot melt layer. In heating at the time of heat fusion, first, the hot melt layer is melted, and then the vibration damping sheet layer is softened. The vibration damping sheet layer after heating is fused and fixed to the vertical surface via the hot melt layer.

[0010]

EXAMPLES First, test examples for obtaining the present invention will be described. A bituminous damping sheet layer and hot melt were prepared to form each test piece. The vibration-damping sheet layer is a commercially available vibration-damping sheet, Sexo Damper DAS (manufactured by Nippon Sexo Industrial Co., Ltd., thickness 1.6 mm, specific gravity 1.6,
A softening point of 140 ° C was used. This damping sheet does not contain iron powder.

The hot melt contains a rubber-based elastomer as a main component, and a softening point (R
& B method) Melt viscosity at 124.0 ° C. and 180 ° C. (measured value by Brookfield viscometer with thermocell) 260
The one of 0 cps was used.

[0012] Then, after the iron melt was blended with the hot melt in the respective required amounts of magnetic powder, 20 x
A 20-cm damping sheet layer was roll-coated on one side to a thickness of 400 μm to form a thin hot melt layer. Next, the damping sheet layer provided with the hot melt layer is magnetized to iron powder in the hot melt layer into a magnetic powder by applying a magnetizing device to obtain a magnetic sticking type damping sheet test piece (test piece 1 in FIG. 3). In addition, in the test piece 1 of FIG. 3, 2 is a damping sheet layer, 3 is a hot melt layer, and 4 is magnetic powder.

The hot melt layer contains magnetic powders having a particle diameter of 2 to 4 microns in the amounts of 30, 40, 60, 80, and 85% by weight, and test pieces I, II, III, IV, and V are formed. did. When the hot melt layer was magnetically adhered to the vertical surface of the steel plate of each of the test pieces I to V, the test piece did not drop and the magnetic sticking property was good (see test piece 1 in FIG. 4. See FIG. 4). 5 indicates a steel plate).

Next, each of the test pieces I to V magnetically adhered to the vertical surface of the steel plate was placed in a heat fusion furnace and heat-fused at 180 ° C. for 30 minutes, and the deviation of each test piece I to V after the heat fusion was performed. The length and the presence or absence of sagging were examined. The results are shown in Table 1.

[0015]

[Table 1]

A conventional magnetically-adhesive damping sheet (thickness 2.0 mm, specific gravity 2.0) in which 60% of iron powder having a particle diameter of 2 to 4 μm was directly mixed with bituminous asphalt was used as a test piece T ( The vibration damping sheet 22 shown in FIG. 5) has a magnetic coercive force of 150 gauss m and a weight of 160 g. As shown in Table 1, when the blending ratio of the iron powder was less than 40%, the magnetic adhesion force was weak and dripping occurred. If the blending amount of iron powder exceeds 80%, roll coating of hot melt mixed with iron powder cannot be performed.

Thus, the test pieces II to IV containing 40 to 80% of iron powder could be well heat-sealed to the steel sheet without any deviation or sagging. That is, according to this test example, it is recognized that the case where 40 to 80% of the iron powder in the hot melt layer is blended is preferable. The thickness of the hot-melt layer is 200 to 200 mm, while the thickness of the damping sheet layer is 1.5 to 3.0 mm.
It is a thin layer of about 400 microns.

In this test example, a bitumen-based damping sheet was used, but according to other test examples, the same results as in the above-described test example were obtained also in the case of a rubber-based or resin-based damping sheet. . The present invention utilizes the results of these test examples.

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a magnetic damping type vibration damping sheet 12 applied to a quarter panel 11 of a vehicle. The vibration damping sheet 12 has substantially the same size as the quarter panel 11 so as to cover the entire side surface of the passenger compartment of the quarter panel 11. The vibration damping sheet 12 is the test piece in the test example described above.
It has the same structure as III. That is, this damping sheet 12
Is a bituminous damping sheet layer 2 having a thickness of 1.6 mm, and a hot-melt layer 3 having a thickness of 400 μm is applied to the entire one surface by roll coating. Hot melt layer 3
60% of magnetized magnetic powder 4A is blended therein.

Then, on the vehicle compartment side surface of the quarter panel 11, the vibration damping sheet 12 with the hot melt layer 3 facing the vehicle compartment side surface is placed. The laminated damping sheets 12 are magnetically held by the magnetic force of the magnetic powder 4A of the hot melt layer 3 (see the damping sheet 12 shown by the phantom line in FIG. 1). After that, the vehicle is transferred to the thermal fusion furnace on the transfer conveyor and
By being heated at 30 ° C. for 30 minutes, the vibration damping sheet 12 is heat-sealed to the quarter panel 11, as shown in FIG.

In the heat-sealing step, the hot-melt layer 3 is melted prior to the softening of the vibration-damping sheet layer 2, and the magnetic powder 4A serves to prevent the vibration-damping sheet layer 2 from slipping and falling. It In the process of heat fusion, the damping sheet 12 can be well fused to the surface of the quarter panel 11 without any deviation.

The damping sheet 12 of this example has a weight of 3200 g per 1 m ² (the magnetic powder 4A in this is 4).
It is 120 gauss at 80 g). On the other hand, the conventional magnetic-adhesion type vibration damping sheet (thickness 2.0 mm, see FIG. 5 vibration damping sheet 22) in which the hot melt layer 3 is not provided and the magnetic powder of 2 to 4 microns is mixed in the vibration damping sheet layer. ) Is 4000 g per 1 m ² (the magnetic powder in this is 2400
It is 150 gauss in g). Thus, the damping sheet 12 of this example is about 20% lighter than the conventional damping sheet 22.

[0023]

INDUSTRIAL APPLICABILITY According to the present invention, the hot-melt layer containing 40 to 80% of magnetic powder is applied to one side of the vibration-damping sheet layer, so that the magnetic powder is kneaded into the vibration-damping sheet. The magnetic powder can be magnetized in a smaller amount as compared with the magnetic adhesion type vibration damping sheet. When the heat-sealing of the vibration-damping sheet of the present invention, the hot-melt layer is melted prior to the vibration-damping sheet layer, so that the vibration-damping sheet can be fused well. Therefore, the damping sheet of the present invention can have a lighter specific gravity and can be made lighter. Since the magnetic powder is an expensive material, the vibration damping sheet of the present invention can be inexpensive.

[Brief description of drawings]

FIG. 1 is a sectional view showing a vibration damping sheet and a quarter panel according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a vibration damping sheet heat-sealed to a quarter panel.

FIG. 3 is a cross-sectional view of a vibration damping sheet test piece.

FIG. 4 is a view showing a fused state of a vibration damping sheet test piece.

FIG. 5 is a cross-sectional view showing a conventional magnetically-adhesive damping sheet and a damping sheet fused to a quarter panel.

[Explanation of symbols]

 2 damping sheet layer 3 hot melt layer 4A magnetic powder 12 damping sheet

Claims (1)

[Claims] 1. A vibration-damping sheet for magnetically holding and heat-sealing a longitudinal surface of a vehicle vibration part, wherein a thin hot-melt layer containing 40 to 80% of magnetic powder is a heat-damping sheet layer. A magnetically-adhesive damping sheet, characterized in that it is adhered to one surface on the fusion side.