JPS6339428B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a sandwich type soundproofing and vibrationproofing structure for a vehicle and a method for manufacturing the same.

(Prior art) Engine vibrations, exhaust system noise, etc. mainly act on the floor of a vehicle from below, and these vibrations are transmitted into the passenger compartment, or low-frequency noise enters the passenger compartment as so-called muffled noise. This tends to cause discomfort to the driver and passengers.

Therefore, vibration damping performance and sound insulation performance of the vehicle body floor are required, and such demands have become particularly important in recent years.

In order to meet the above requirements, methods have recently begun to be adopted in which the vehicle body floor is constructed in the form of a so-called sandwich panel.

As shown in FIGS. 1 and 2, the conventional sanderch panel has a structure in which a vehicle side panel, for example, a floor panel 1, is made of a polymeric viscoelastic material with a high specific gravity and a bituminous damping material ( A so-called Melsheet 2 as a soundproofing and vibration-proofing material mainly made of (for example, thermoplastic rubber, etc.) is arranged, and a floor upper panel 3, for example, as a holding panel for the Melsheet 2 is placed on top of it. The Melsheet 2 is integrated with the floor panel 3 by heating and fusing the Melsheet 2 by passing it through a heating booth in an intermediate painting process.

The sandwich panel S cooperates with the felt 4 and the carpet 5, which have high sound-absorbing performance and are disposed thereon, to dramatically improve the vibration-damping performance and the sound-insulating performance.

However, during heat curing work, the Melsheet 2 first expands by a predetermined amount by heating, and then shrinks due to fusion, so that after shrinking, there is a gap between the floor panel 1 and Melsheet 2 or the Melsheet 2 and the floor upper panel 3. In some cases, voids were formed, making it impossible for the above-mentioned sandwich panel S to exhibit its intended performance.

That is, in the conventional sand bench panel S, it is relatively easy to ensure a good welding rate in areas where the surface changes are small, such as the needle lower panel, but it is relatively easy to ensure a good welding rate in areas where the surface changes little, such as the needle lower panel. For areas with many unevenness, use Melsheet 2 above.
There was a problem in that it was difficult to secure the desired welding rate if only the welding method was used alone.

In the sandwich panel structure, if there is a gap (air layer) between the vehicle side panel and the holding panel, the presence of the gap will reduce the performance, especially from the standpoint of vibration damping performance, so it is also important from the quality point of view. Improving the fusion rate remained an issue to be solved.

(Objective of the Invention) An object of the present invention is to solve the above-mentioned conventional problems, improve the degree of adhesion and fusion of a sandwich structure for a vehicle, and enhance the soundproofing and vibrationproofing effects.

(Structure of the Invention) In order to achieve the above object, the sandwich-type soundproofing and vibration-proofing structure for a vehicle according to the present invention includes a heat-welding type sheet layer and a heat-foaming type sheet layer between the vehicle side panel and the holding panel. It is characterized by the formation of

In addition, in order to achieve the above object, the method for manufacturing a soundproof and vibration-proof structure for a sandwich type structure for a vehicle according to the present invention includes disposing a heat-welding type sheet and a heat-foaming type sheet on a vehicle side panel, The method is characterized in that both sheets are pressed and fixed with a presser panel and then heated to form the thermally foamable type sheet.

(Effects of the Invention) In the present invention having the above configuration, in addition to the heat-welding type sheet that has been commonly used as a soundproofing and vibration-proofing material for sanderch panels,
By combining heat foam type sheets,
The heat foaming type sheet foams when heated, and the foaming pressure of the heat welding type sheet and the heat foaming type sheet creates gaps between the vehicle side panel and the holding panel at irregularities such as beads and embossments where gaps are likely to occur. In addition, due to the foaming pressure during foaming and the reaction force from the heat-welding type sheet, the adhesion to the vehicle side panel and the presser panel is further increased, and the restraining force between the vehicle side panel and the presser panel is increased. As a result, the adhesion and degree of welding as a sanderch type structure are significantly improved compared to conventional examples, making it possible to dramatically improve soundproofing and vibrationproofing performance.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 3 is a sectional view of essential parts showing an embodiment of a sanderch panel S as a sanderch-type soundproofing and vibration-proofing structure for a vehicle according to the present invention, in which 1 is a floor panel as a vehicle side panel; 3 is a sheet layer made of a heat-welding type sheet, 3 is a floor upper panel as a presser panel, and 6A is a sheet layer made of a heat-foamed type sheet.

Here, the above-mentioned heat-welding type sheet is made of a polymeric viscoelastic material and is mainly made of a bituminous thread damping material,
Above the specified temperature (approximately 110℃ or above in the case of this example)
A thin sheet of material that can be softened and welded to an adjacent member (in this example, floor panel 1 or floor upper panel 3) when heated by heat, such as Melsheet, etc. It is something like that.

In addition, the above-mentioned heat-foamed sheet is a foamed material containing a viscoelastic substance, and is made by using a heat-welding adhesive.
It is a sheet compressed to a thickness of about 1/10 to 1/10, and the adhesive melts at a predetermined temperature (the melting temperature of the adhesive, at least the temperature at which the heat-welding type sheet can be softened and welded). This is a type of sheet that releases the binding force of the compressed foam material, and then expands and recovers to its pre-compression thickness by continuously foaming due to heat.

As the heat-foamable sheet, there is, for example, a material (trade name: Telomagic) made by mixing soft polyurethane with a viscoelastic resin, a foaming agent, and the like.

Next, a method for manufacturing the sanderch panel S according to this embodiment will be explained with reference to FIGS. 4 to 8.

First, as shown in FIG. 4, in the painting intermediate process during the vehicle assembly and manufacturing process, for example, the inner panel 7 and the sill outer panel 8 as sill members are
A heat-welding type sheet 2 and a heat-foaming type sheet 6 are placed on top of each other at the same time on the floor panel 1 which is fixed to the floor panel 1, and then, as shown in FIG. The floor upper panel 3 is placed, and the end portion of the floor upper panel 3 is pressed and fixed with a suitable fixing member such as a retainer 9, as shown in FIG.

At this stage, for example, the embossed portions 10 formed on the floor panel 1 and the floor upper panel 3
In addition, in areas such as beads 11 formed continuously or intermittently at the end of the floor upper panel 3, both the sheets 2 and 6 and the floor panel 1
A considerable gap 12 exists between the upper floor panel 3 and the floor upper panel 3.

However, in this embodiment, after setting on the vehicle,
For example, heat of 110° C. or higher is applied for about 20 to 30 minutes using a coating oven (not shown) or the like. Then, the adhesive that restrained the heat-foamable sheet 6 into a compressed shape first melts, releasing the restraining force of the foam, and then continuously foaming due to heat, forming the sheet 6.
Heat welding type sheet 2 which expands to its uncompressed state and becomes soft and weldable by heat.
Apply foaming pressure to Due to this pressure, the heat-welding type sheet 2 is welded without any gaps to the floor panel 1 having a complicatedly shaped surface such as the embossed portion 10 as shown in FIG.

Further, an embossed portion 10 is formed on the floor upper panel 3 due to the foaming pressure of the heat-foamable sheet 6 itself and the reaction force against the pressure applied to the heat-welded type sheet 2.
Also in the bead 11, the void 12 is eliminated,
The expanded thermal foam type sheet 6 is densely packed, and the adhesion is significantly improved compared to the conventional example.

In addition, with respect to the clearance between the floor panel 1 and the floor upper panel 3 before heating, the thickness of the sandwich panel S after heat treatment is set to be larger than the clearance dimension, so that the heat welding type sheet 2 is welded. Adhesion shall be ensured even after shrinkage.

After the heat treatment, finishing materials such as felt 4 and carpet 5 may be placed on the sandwich panel S as shown in FIG.

In this example, due to the synergistic effect of the heat foam type sheet 6 and the heat weld type sheet 2 as described above, the degree of adhesion and welding of the sandwich panel S is dramatically improved compared to the conventional example, and the generation of voids is ensured. Therefore, both soundproofing performance and vibrationproofing performance are improved, and in particular, it is characterized by a marked improvement in vibrationproofing performance.

In this embodiment, an example was shown in which the heat-foamable sheet 6 was disposed on the upper surface of the heat-welding type sheet 2, but the configuration may be reversed.

Next, FIGS. 9A to 9D are drawings showing another manufacturing method of the Sanderch-type soundproofing and vibration-proofing structure for vehicles according to the present invention. Floor panel 1 as shown in
Only the heat-welding type sheet 2 is placed on top and heated to a predetermined temperature or higher using a heating device or a painting oven to weld it to the floor panel 1 in advance, and then the heat-foaming type sheet 2 is placed on the floor panel 1 as shown in Figure 9. The sheet 6 is placed on the heat-welding type sheet 2, and then the floor upper panel 3 as a holding panel is placed as shown in FIG. As in Example 1, the heat-foamable sheet 6 is heated in a coating oven at 110°C or higher for about 20 to 30 minutes to foam the air gap between the floor upper panel 3 and the heat-welded sheet 2. The sandwich panel S is formed by densely filling the parts.

In this embodiment, since the heat-welding type sheet 2 is tightly welded to the floor panel 1 as the vehicle side panel in advance, the heat-welding type sheet 2 is heated to a temperature higher than enough to foam the heat-foaming type sheet 6 during the second heating. Only heating is required, and in the second heating, it is only necessary to foam the heat-foamable sheet 6 to fill the voids, so the foaming pressure etc. can be set lower than in the first embodiment. It can produce unique effects such as:

Next, FIG. 10 shows another embodiment of the sandwich panel S as a sandwich-type soundproof and vibration-proof structure for vehicles according to the present invention. It has a three-layer sheet structure in which a welding type sheet layer 2A is formed.

Therefore, both of the above-mentioned two manufacturing methods can be applied to the manufacturing method of the sandwich panel S of this embodiment.

In this embodiment, the upper and lower heat-welding type sheets 2 can be tightly welded to the floor panel 1 and the floor upper panel 3 due to the foaming pressure of the heat-foaming type sheet 6, so that the floor upper panel 3 as a presser panel is particularly advantageous. The adhesion between the sheet layer and the sheet layer can be further improved.

In each of the above-mentioned embodiments, an example was shown in which a heat-foamable sheet 6 which had been compression-molded in advance was used, but depending on the design conditions, a normal foamable resin material could be used instead of the sheet 6 to foam when heated. Needless to say, it is also possible to fill the voids by letting the particles dry.

Further, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the gist of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part of a car body floor using a Sanderuch-type soundproofing and vibration-proofing structure; FIG. 2 is a cross-sectional view of a main part showing an example of how the Sanderuch-type soundproofing and vibration-proofing structure is assembled; FIG. 3 is a sectional view of a main part showing a first embodiment of a soundproofing and vibrationproofing structure according to the present invention, and FIGS. 4 to 8 each show an example of a method for manufacturing the soundproofing and vibrationproofing structure. The explanatory diagrams shown in Fig. 9 A to D are the soundproofing,
FIG. 10 is an explanatory diagram showing a second embodiment of the method for manufacturing a vibration-proof structure, and FIG. 10 is a cross-sectional view of a main part showing an example other than the sound-proofing and vibration-proofing structure according to the present invention. S...Sand German beach panel (Sand German beach type soundproofing and vibration damping structure), 1... Floor panel (vehicle side panel), 2... Heat welding type sheet, 3... Floor upper panel (pressing panel), 6... Heat foam type sheet.

Claims (1)

[Scope of Claims] 1. A sandwich-type soundproofing and vibration-proofing structure for a vehicle, characterized in that a heat-welding type sheet layer and a heat-foaming type sheet layer are formed between a vehicle side panel and a holding panel. 2. The heat-welding type sheet layer is a sheet layer made of a polymeric viscoelastic material and mainly made of a bituminous vibration damping material, and is a sheet layer that is welded to the vehicle side panel or the presser panel at a predetermined temperature or higher. Sanderch-type soundproofing and vibration-proofing structure for vehicles as described in . 3 The heat-foamable sheet layer is a foam containing a viscoelastic substance, and is compression-molded to a thickness of 1/5 to 1/10 using a heat-welding adhesive. The sandwich-type soundproofing and vibrationproofing structure for a vehicle according to claim 1, wherein the sheet layer is melted and expanded by foaming to the thickness before compression. 4. A heat-welding type sheet and a heat-foaming type sheet are arranged on the vehicle side panel, and after pressing and fixing both sheets with a presser panel, heating is performed to foam the heat-foaming type sheet. A method for manufacturing a sandwich-type soundproof and vibration-proof structure for vehicles. 5. In the intermediate painting process, the heat-welding type sheet and the heat-foaming type sheet are superimposed and arranged on the vehicle side panel, and after being pressed and fixed with the presser panel, heat of 110°C or higher is applied for 20 to 30 minutes. 5. The method for manufacturing a sanderch type soundproofing and vibrationproofing structure for a vehicle according to claim 4, wherein the heating is carried out for a minute. 6. After the heat-welding type sheet is fused onto the vehicle panel in a painting oven in the intermediate painting process, the heat-foaming type sheet is placed on the heat-welding type sheet and pressed with the presser panel; 5. The method of manufacturing a sanderch type soundproofing and vibrationproofing structure for a vehicle according to claim 4, which comprises applying heat at 110° C. or higher for 20 to 30 minutes after fixing.