JP2003146208A - Floor plate for vehicle and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floor plate for high-speed vehicle and its manufacture which restrains transmission of car body vibration from below the floor and noise outside the vehicle, while suppressing increase of weight and reduces radiated noise in the vehicle. SOLUTION: Between at least one of face plates of the floor plate holding a honeycomb structure 4 between an upper face plate 2 and a lower face plate 3 and the honeycomb structure 4, a vibration shut-down layer 5 comprising rubber-state elastic bodies 7a and 7b with a rubber-state elastic body or fiber layer 6 interposed between them is interposed. In order to manufacture, (1) the vibration shut-down layer 5 made of the rubber-state elastic body is formed in advance, the vibration shut-down layer 5 is stacked on at least one of the upper face plate 2 and the lower face plate 3, the vibration shut-down layer 5 is opposed to the honeycomb structure, and the upper plate 2 and the lower plate 3 are bonded to the honeycomb structure. (2) After unvulcanized rubber-state elastic body is stacked on the upper and the lower faces of the fiber layer 6 in advance, the stacked body is vulcanized to have the vibration shut-down layer 5, the vibration shut-down layer 5 is stacked on at least one of the upper face plate 2 and the lower face plate 3 through a thermosetting adhesive, the vibration shut-down layer 5 is opposed to the honeycomb structure 4, and the upper face plate 2 and the lower face plate 3 are integrated to the honeycomb structure 4 through the thermosetting adhesive and then, pressurized and heated for a predetermined time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle floorboard and a method for manufacturing the same, and more particularly to a vehicle floorboard which suppresses propagation of exterior noise and vehicle body vibration on a floorboard for high-speed vehicles such as Shinkansen and a method for manufacturing the same. It is a thing.

[0002]

2. Description of the Related Art In a floorboard for a high-speed vehicle such as a Shinkansen, so-called body vibration such as vehicle vibration during driving or noise from a drive unit and outside noise of the vehicle cannot be avoided from being propagated from under the floor, and this becomes a radiated sound inside the vehicle. It was one of the factors that make passengers uncomfortable.

Since vehicles in the future are required to be even faster and lighter in weight, there is a strong demand for a next-generation floor material that suppresses propagation of exterior noise and vehicle vibration while suppressing an increase in total weight as much as possible. It became so.

The existing high-speed vehicle floor plate is required to be as light as possible while maintaining sufficient compressive strength. As a result, as shown in FIG. 6, the floor plate 1 is composed of an upper plate 2 and a lower plate 3. The honeycomb structure 4 is made of a light metal such as aluminum and is sandwiched between the honeycomb structures 4.

However, in the structure of the floor plate 1 as described above, the honeycomb structure 4 serves as a vibration transmission path from the viewpoint of acoustic characteristics, and the vibration of the vehicle body and the noise outside the vehicle which are transmitted to the lower surface plate 3 and vibrated are the same as the honeycomb structure 4. Is propagated to the upper surface plate 2 while being vibrated vertically, and this is vibrated to become a radiated sound in the vehicle.

As a method for suppressing the propagation of the vehicle body vibration and the noise outside the vehicle, for example, (a) a method of increasing the upper and lower face plates to increase the mass of the structure, and (b) a method of increasing the thickness of the honeycomb structure Measures such as a method of increasing the overall thickness of the floorboard by increasing the thickness have been studied, but all of them have not been adopted because they increase the weight and hinder high-speed operation.

Instead of this, attempts have been made to treat the face plate with a damping material or to use a damping steel plate (aluminum sandwich plate) for the face plate in order to improve the sound transmission loss.

[0008]

However, since the countermeasures based on the above-mentioned attempts cannot exhibit the function of attenuating the longitudinal wave and transverse wave components of the honeycomb structure, the improvement for suppressing the transmission of the vehicle body vibration and the noise outside the vehicle from under the floor. Is not connected to.

An object of the present invention is to suppress the propagation of vehicle body vibrations and vehicle exterior noise from under the floor while suppressing the increase in weight,
It is an object of the present invention to provide a floor plate for a high-speed vehicle that reduces radiated noise in the vehicle and a method for manufacturing the same.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a method for reducing vehicle body vibrations and vehicle exterior noise from below the floor between a honeycomb structure and at least one face plate of a top plate and a bottom plate. The purpose of the present invention is to interpose a vibration blocking layer for suppressing propagation, and it is roughly divided into two inventions depending on the structure of the vibration blocking layer and the way of applying the vibration blocking layer.

A vehicle floorboard according to a first aspect of the present invention is a vehicle floorboard in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, and at least one of the upper surface plate and the lower surface plate and the honeycomb structure. The gist of the invention is to interpose a vibration isolation layer made of a rubber-like elastic body between them, and chloroprene rubber or epoxy resin is preferably used as the rubber-like elastic body.

According to a first aspect of the present invention, there is provided a method of manufacturing a vehicle floorboard in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate of the vehicle floorboard. It is molded, and the vibration isolation layer is laminated on at least one of the upper surface plate and the lower surface plate, the vibration isolation layer side is opposed to the honeycomb structure, and the upper surface plate and the lower surface plate are formed of the honeycomb. The main point is to adhere to the structure.

As a result, the flexible vibration isolation layer exerts a vibration insulation effect and reduces the radiated sound inside the vehicle. In particular, it is effective in reducing the in-vehicle sound in a low frequency band of 500 Hz or less, which is said to be caused by vehicle body vibration.

On the other hand, the vehicle floor board according to the second aspect of the present invention is a vehicle floor board in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, and at least one face plate of the upper surface plate and the lower surface plate and the honeycomb structure. It is preferable that the rubbery elastic body is made of chloroprene rubber, since a vibration isolation layer made of a rubbery elastic body having a fibrous layer interposed between the body and the body is provided.

A method for manufacturing a vehicle floorboard according to a second aspect of the present invention is a method for manufacturing a vehicle floorboard in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, wherein the upper and lower surfaces of the fiber layer are not yet vulcanized. After laminating the rubber-like elastic body to form a laminate, the laminate is vulcanized to form a vibration isolation layer, and the vibration isolation layer is bonded to the upper plate and the lower plate via a thermosetting adhesive. Laminated on at least one face plate, with the vibration isolation layer side facing the honeycomb structure, the upper face plate and the lower face plate are combined with the honeycomb structure via a thermosetting adhesive, and thereafter, The point is to heat under pressure for a predetermined time.

Thus, the fiber layer prevents the rubber-like elastic body on the face plate side of the vibration isolation layer from entering the honeycomb structure side due to the pressure and heating during manufacturing, so that the rubber on the face plate side of the vibration isolation layer is suppressed. A floorboard having a set sound transmission loss can be obtained without changing the thickness of the elastic body.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. In each figure, the same components are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 1 is a partial cross-sectional view showing the cross-sectional structure of the floor plate in the first embodiment of the present invention. In the floor plate 1, a honeycomb structure 4 is sandwiched between an upper plate 2 and a lower plate 3. A vibration isolating layer 5 made of a rubber-like elastic material is interposed between the upper surface plate 2 and the honeycomb structure 4.

The rubber-like elastic body constituting the vibration isolation layer 5 is not particularly limited as long as it is a rubber or a flexible resin material, but since both rubber materials and resin materials are required to have flame retardancy, they are chloroprene. An epoxy resin containing rubber or flame retardant is preferable, and an epoxy resin containing more flexibility is more preferable.

Here, the vibration isolation layer 5 interposed between the upper surface plate 2 and the honeycomb structure 4 absorbs the vibration propagating from the lower surface plate 3 to the honeycomb structure 4 and exerts an insulating function. It serves to damp the vibration that propagates to the.

As a result, the radiated sound inside the vehicle is reduced, and in particular, the effect of reducing the vehicle interior noise in the low frequency band of 500 Hz or less, which is said to be caused by the vehicle body vibration, is great.

The thickness of the vibration isolation layer 5 varies depending on the scale of the floor plate 1, but is 1 to 2 m from the viewpoint of suppressing the increase in the weight of the floor plate 1.
It is preferably about m.

FIG. 2 is a partial cross-sectional view showing a cross-sectional structure of a floor plate for explaining another embodiment of the first invention, which is made of a rubber-like elastic material between the lower plate 3 and the honeycomb structure 4. The case where the vibration isolation layer 5 is interposed is shown.

Here, the vibration isolation layer 5 interposed between the lower surface plate 3 and the honeycomb structure 4 exerts an insulating function of the vehicle body vibration transmitted to the lower surface plate 3 and vibrated, and propagates to the honeycomb structure 4. Play a role in damping the vibration. This allows
Reduces radiated sound inside the vehicle.

FIG. 3 is a partial cross-sectional view showing a cross-sectional structure of a floor plate for explaining another embodiment of the first invention, in which a space between the top plate 2 and the honeycomb structure 4 and a bottom plate 3 and the honeycomb are shown. The figure shows a case where a vibration isolation layer 5 made of a rubber-like elastic material is interposed between the structures 4.

Here, the vibration isolation layer 5 interposed between the lower surface plate 3 and the honeycomb structure 4 exerts an insulating function of the vehicle body vibration transmitted to the lower surface plate 3 and vibrated, and propagates to the honeycomb structure 4. The vibration isolation layer 5 plays a role of attenuating the vibration, and in addition, the vibration isolation layer 5 interposed between the upper surface plate 2 and the honeycomb structure 4 is
It plays a role of absorbing the vibration propagating to the honeycomb structure 4 and exerting an insulating function to damp the vibration propagating to the upper surface plate 2.

In the floorboard 1 according to the first invention shown in FIGS. 1 to 3 described above, a vibration isolation layer 5 made of a rubber-like elastic material is formed in advance, and the vibration isolation layer 5 is used as the upper surface plate 2 and the lower surface plate. 3 is bonded to at least one of the face plates, the vibration blocking layer 5 side is made to face the honeycomb structure 4, and the upper face plate 2 and the lower face plate 3 are bonded to the honeycomb structure 4.

The above-mentioned adhesion is a usual adhesion at room temperature,
As the adhesive, an epoxy resin or elastic epoxy resin adhesive is preferably used.

The floorboard 1 according to the second invention differs from the floorboard 1 according to the first invention in the structure of the vibration isolation layer 5. The vibration isolation layer 5 includes a fiber layer 6 as shown in FIG. The floor plate 1 is made up of the rubber-like elastic bodies 7a and 7b.
As illustrated in FIG. 3, the rubber-like elastic body 7b on the lower surface side of the vibration isolation layer 5 is adhered onto the lower surface plate 3, and the rubber-like elastic body 7a on the upper surface side is arranged to face the honeycomb structure 4 side.

The fiber layer 6 is not particularly limited, but is preferably a woven or non-woven fabric made of organic fibers such as nylon, polyester, polyethylene and polyvinyl alcohol, or inorganic fibers such as carbon and glass.
It is preferable that the rubber-like elastic bodies 7a, 7b, 7 are chloroprene rubber sheets excellent in flame retardancy.

In the production of the floor plate 1 according to the second invention, as will be described later, between the upper plate 2 and / or the lower plate 3 and the vibration isolation layer 5, between the vibration isolation layer 5 and the honeycomb structure 4, And between the upper surface plate 2 or the lower surface plate 3 and the honeycomb structure 4,
In the case where the vibration isolation layer 5 is composed of a single rubber-like elastic body in order to be bonded using a thermosetting adhesive,
In the process of pressurizing and heating to cure the adhesive, the rubber-like elastic body forming the vibration isolation layer 5 enters the honeycomb structure 4 side,
The vibration isolation layer 5 originally set for the vibration isolation layer 5 of the floorboard 1
It has been found that the thickness cannot be maintained, and the vibration damping effect is reduced as the thickness is reduced.

The fiber layer 6 plays a role of preventing the rubber-like elastic body constituting the vibration isolation layer 5 from invading into the honeycomb structure 4 side indefinitely. As shown in FIG.
As shown in a part of the cross-sectional structure, the rubber-like elastic body 7a is prevented from entering the honeycomb structure 4 side in a state where a part of the rubber-like elastic body 7a enters the honeycomb structure 4 side.

With this, since the thickness of the vibration isolation layer can be controlled, it is possible to obtain the floor plate having the sound transmission loss as originally assumed.

That is, in the method for manufacturing the floorboard 1 according to the second aspect of the present invention, the unvulcanized rubber-like elastic material is laminated on the upper and lower surfaces of the fiber layer 6 in advance to form a laminated body, and then the laminated body is vulcanized. To form the vibration blocking layer 5, and the vibration blocking layer 5 is laminated on at least one of the upper surface plate 2 and the lower surface plate 3 via a thermosetting adhesive, and the vibration blocking layer 5 side is a honeycomb. The upper surface plate 2 and the lower surface plate 3 are united with the honeycomb structure 4 via a thermosetting adhesive so as to face the structure 4, and thereafter, they are pressurized and heated for a predetermined time.

The above-mentioned pressurizing and heating depends on the kind of the thermosetting adhesive, but it is usually about 150 when pressed with a press.
Perform at 30 ° C for about 30 minutes. [Example 1] Two aluminum plates having a size of 1 m x 2 m and a thickness of 1 mm were prepared, and a thickness of 2 mm was provided on one side of each aluminum plate.
The chloroprene rubber sheets having different hardnesses (Shore hardness: 40 degrees and 60 degrees) were bonded at room temperature as the vibration blocking layer 5 to manufacture two types of upper plate 2 with the vibration blocking layer.

An aluminum honeycomb core having a thickness of 20 mm is adhered to the vibration blocking layer 5 (rubber sheet) side of the top plate 2 with each vibration blocking layer 5, and the size is 1 m × 2 m and the thickness is 0.5.
2 mm floor plate having the structure shown in FIG. 1 by bonding an aluminum plate of mm to the lower surface plate 3 on the opposite side of the aluminum honeycomb core.
(Invention product A (Shore hardness of the vibration blocking layer 5 is 40 degrees) and Invention product B (Shore hardness of the vibration blocking layer 5 is 60 degrees)) were manufactured.

This is JISA 1416 (2000)
The sound transmission loss (dB) by the reverberation room method was measured according to "Measuring method of air sound insulation performance of building members in the laboratory", and the result is compared with the conventional product in which the vibration insulation layer 5 is not interposed. 7 shows.

From the results shown in FIG. 7, it was found that the invention products A and B having the vibration isolation layer 5 interposed therebetween had a large sound transmission loss over a wide frequency band compared to the conventional product, and suppressed the sound transmission as a floor plate. did.

As shown in FIG. 7, the sound transmission loss value varies depending on the hardness of the rubber sheet interposed as the vibration isolation layer 5, and a rubber sheet having a low hardness is interposed in a relatively low frequency band. It has been confirmed that it is more advantageous, and it tends to be advantageous to interpose a rubber sheet having a slightly high hardness as the frequency increases to some extent. [Example 2] An aluminum plate having a size of 1 m x 2 m and a thickness of 1 mm was prepared, and a vibration isolation layer 5 was formed on one surface of the aluminum plate.
Polyamine 20 in 80 parts by weight of urethane modified epoxy resin
By weight, 20 parts by weight of the liquid phosphoric acid flame retardant and 70 parts by weight of the bromine flame retardant were mixed, coated to a thickness of 1 mm, and cured for 24 hours.

A thickness of 20 is provided on the vibration isolation layer 5 side of the top plate 2.
mm aluminum honeycomb core is bonded by using the flexible epoxy resin having the above composition as an adhesive, and the size is 1 m × 2.
An aluminum plate having a thickness of 0.5 mm and a thickness of 0.5 mm was adhered to the opposite side of the aluminum honeycomb core as a lower surface plate 3 and cured and cured at room temperature for 24 hours to produce a floor plate 1 (invention product) having the structure shown in FIG.

This is subjected to JISA in the same manner as in [Example 1] above.
1416 (2000) “Transmission loss (dB) of sound by the reverberation chamber method” was measured according to “Measurement method of air sound insulation performance of building members in the laboratory”, and the result was compared with the conventional product without the vibration insulation layer 5. The loss level display is shown in FIG.

From the results shown in FIG. 8, it was found that the transmission loss was improved by suppressing the vibration by the flexible epoxy resin in a wide low frequency band. [Example 3] A woven fabric prepared by weaving nylon cords having a size of 1 m x 2 m in a mesh structure was prepared, and an unvulcanized chloroprene rubber sheet having a thickness of 1 mm was attached to the upper surface and a thickness of 2 mm was attached to the lower surface. And vulcanized to obtain a vibration isolation layer 5.

An aluminum plate having a size of 1 m × 2 m and a thickness of 0.5 mm is used as a lower plate 3, and a vibration isolation layer 5 having a thickness of 2 mm is formed on the upper surface of the aluminum plate through an epoxy resin film adhesive. Is placed so that it is the bottom surface, and the thickness of 20
mm aluminum honeycomb core is placed on the upper surface of the aluminum honeycomb core with an epoxy resin film adhesive, and the size is 1 m × 2 m.
An aluminum plate having a thickness of 1 mm was placed as the upper plate 2, and the whole was pressed and heated at 150 ° C. for 30 minutes by a press to manufacture a floor plate 1 (invention product) having a structure shown in FIG.

As in the above-mentioned [Embodiment 1], this is compliant with JISA.
1416 (2000), "Transmission loss (dB) of sound by the reverberation chamber method" was measured according to "Method of measuring air sound insulation performance of building members in a laboratory", and the result was measured separately for a thickness of 2 mm without interposing the fiber layer 6. FIG. 9 shows the relative loss level display of the comparative product to which the vibration isolation layer 5 made of rubber is applied.

From the results shown in FIG. 9, it was found that the transmission loss was improved in a wide frequency band.

[0046]

As described above, the floor plate 1 of the present invention is
A vibration isolation layer 5 made of rubber-like elastic bodies 7a and 7b in which a rubber-like elastic body or a fibrous layer 6 is interposed between at least one of the upper surface plate 2 and the lower surface plate 3 and the honeycomb structure 4 is interposed. Since it is configured so that the weight increase of the floorboard 1 is suppressed, the vibration isolation layer 5 having flexibility exerts the vibration insulation effect, absorbs the propagation of the vehicle body vibration sound or the vehicle exterior sound, and reduces the radiated sound inside the vehicle. Made it possible. In particular, it is effective in reducing the in-vehicle sound in the low frequency band of 500 Hz or less, which is said to be caused by vehicle body vibration.

Further, in the case of the second invention in which a thermosetting adhesive is used in the production of the floorboard 1, the rubber-like elastic bodies 7a and 7b having the fiber layer 6 interposed as the vibration isolation layer 5 are used. The floor plate having the sound transmission loss as set can be obtained without irregularly changing the thickness of the vibration isolation layer 5 due to heating during manufacturing.

Further, since the floorboard 1 according to the present invention is relatively similar in structure to the existing floorboard in any form, it is necessary to introduce special mechanical equipment or to significantly change the manufacturing process. The floorboard 1 can be manufactured without doing so.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a sectional structure of a floorboard according to an embodiment of the first invention.

FIG. 2 is a partial sectional view showing a sectional structure of a floorboard according to another embodiment of the first invention.

FIG. 3 is a partial sectional view showing a sectional structure of a floorboard according to another embodiment of the first invention.

FIG. 4 is a partial cross-sectional view showing a cross-sectional structure of a vibration isolation layer in the floorboard of the second invention.

FIG. 5 is a partial sectional view showing a sectional structure of a floorboard according to an embodiment of the second invention.

FIG. 6 is a partial sectional view showing a sectional structure of a conventional floorboard.

FIG. 7 is a graph showing a sound transmission loss situation of a floorboard when chloroprene rubber is used as a material of the vibration isolation layer of FIG.

8 is a graph showing a sound transmission loss situation of a floorboard when an epoxy resin is used as a material of the vibration isolation layer of FIG.

9 is a graph showing a sound transmission loss situation of a floorboard when a chloroprene rubber sheet having a fiber layer interposed is used as the vibration isolation layer of FIG.

[Explanation of symbols]

1 Floor board 2 Top board 3 Bottom plate 4 Honeycomb structure 5 Vibration isolation layer 6 Fiber layer 7a, 7b Rubber-like elastic body

Continued front page    (72) Inventor Hideo Kikuchi             2-1, Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd.             Ceremony Company Hiratsuka Factory F term (reference) 5D061 AA04 AA06 BB13 BB37 DD02

Claims (7)

[Claims] 1. A vehicle floor plate having a honeycomb structure interposed between an upper plate and a lower plate, wherein a rubber-like elastic body is provided between at least one of the upper plate and the lower plate and the honeycomb structure. A floor plate for a vehicle configured by interposing a vibration isolation layer. 2. The floor plate for a vehicle according to claim 1, wherein the rubber-like elastic body is made of chloroprene rubber. 3. The vehicle floorboard according to claim 1, wherein the rubber-like elastic body is made of an epoxy resin. 4. A manufacturing method for manufacturing a vehicle floorboard in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, wherein a vibration isolation layer made of a rubber-like elastic material is formed in advance,
The vibration isolation layer is laminated on at least one of the upper surface plate and the lower surface plate, the vibration isolation layer side is opposed to the honeycomb structure, and the upper surface plate and the lower surface plate are bonded to the honeycomb structure. A method of manufacturing a floor plate for a vehicle, comprising: 5. A floor plate for a vehicle in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, wherein a fiber layer is interposed between at least one of the upper surface plate and the lower surface plate and the honeycomb structure. A floorboard for a vehicle constituted by interposing a vibration isolation layer made of a rubber-like elastic body. 6. The vehicle floorboard according to claim 5, wherein the rubber-like elastic body is made of chloroprene rubber. 7. A manufacturing method for manufacturing a vehicle floorboard in which a honeycomb structure is interposed between an upper surface plate and a lower surface plate, wherein an unvulcanized rubber-like elastic material is previously laminated on upper and lower surfaces of a fiber layer to form a laminate. After molding, the laminated body is vulcanized to form a vibration isolation layer, and the vibration isolation layer is laminated on at least one of the upper plate and the lower plate via a thermosetting adhesive, and the vibration is applied. The blocking layer side is opposed to the honeycomb structure, the upper surface plate and the lower surface plate are combined with the honeycomb structure via a thermosetting adhesive, and then pressure heating is performed for a predetermined time. Vehicle floorboard manufacturing method.