JP2017007517A - Sound insulating structure of cabin floor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase sound insulation from a floor panel without mischievously increasing the mass and density of a floor carpet.SOLUTION: A floor carpet 20 is laid on a floor panel 1 constituting a cabin floor surface. The floor carpet 20 has a surface skin layer 20A having sealability, and a sound absorption layer 20B arranged on a lower surface side of the surface skin 20A, and forming a circulation layer of air. A space (space part where the sound absorption layer 20B is positioned) between the surface skin 20A and the floor panel 1 is a sealed structure by a seal member 30 arranged so as to surround the sound absorption layer 20B. The seal member 30 can be pressed (adhered) to the floor panel 1 by a pressing member 40 fixed to a vehicle body side by fixtures 50.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a sound insulation structure for a passenger compartment floor.

  In an automobile as a vehicle, it is important how to reduce noise transmitted to the passenger compartment through a floor panel, particularly road noise. For this reason, a floor carpet is laid on the floor panel.

  Patent Document 1 discloses a floor carpet having a multilayer structure in order to sufficiently perform sound insulation. Further, Patent Document 2 discloses a sound insulation mechanism of a floor carpet that is described using a mass and a spring system.

JP 2008-285026 A JP 2003-104135 A

  In order to enhance the sound insulation from the floor panel, it is common to increase the mass and density of the floor carpet, as used in luxury cars. However, in this case, the weight of the floor carpet is greatly increased and the cost is greatly increased.

  The present invention has been made in view of the above circumstances, and its purpose is to improve the sound insulation from the floor panel without unnecessarily increasing the mass and density of the floor carpet. The object is to provide a sound insulation structure for the room floor.

In order to achieve the above object, in the present invention, basically, the cushion material located on the subepidermal surface side of the floor carpet becomes an air circulation layer, and this air circulation layer is reduced in noise. The sound insulation effect is enhanced by effectively using it as a space for resonance. Specifically, as described in claim 1, a sound insulation structure for a passenger compartment floor in which a floor carpet is laid on a floor panel constituting the passenger compartment floor surface,
The floor carpet has an airtight skin layer, and a sound absorbing layer made of a cushioning material disposed on the lower surface side of the skin layer to form an air circulation layer,
The space between the skin layer and the floor panel is sealed by a sealing member, and the portion where the sound absorbing layer is located between the skin layer and the floor panel has a sealed structure.
It is like that.

  According to the above-described solution technique, the space of the portion where the sound absorbing layer is located can be a sealed structure, and a sound insulation effect by resonance can be sufficiently obtained. The sound insulation effect by this resonance, the sound insulation effect by the sound absorption in the sound absorption layer, and the sound insulation effect by the skin layer having a sealing property can sufficiently enhance the sound insulation effect while making the floor carpet as light and thin as possible. .

A preferred mode based on the above solution is as described in claim 2 and the following claims. That is,
The floor panel is formed so as to have a plurality of substantially flat floor pan portions divided into front, rear, left and right,
The seal member is provided for each of the plurality of floor pan portions so as to surround a peripheral portion of each floor pan portion.
(Corresponding to claim 2). In this case, it is preferable to enhance the sound insulation effect by adopting a mutually independent sealing structure for each of the floor pan portions that are substantially flat where noise transmission is a problem. Further, it is preferable for simplifying the seal structure while ensuring reliable sealing performance by the seal member. In addition, after laying the floor carpet, when performing maintenance on various wirings arranged between the floor carpet and the floor panel, it is only necessary to release the seal by the seal member only in a portion requiring maintenance. Therefore, it is preferable in terms of improving maintainability.

  The sealing member is pressed against the floor panel by a pressing member that is detachably fixed by a fixture to the floor panel or a vehicle body strength member in the vicinity thereof (corresponding to claim 3). . In this case, the floor carpet is fixed to the floor panel using the pressing member, and sufficient sealing performance is secured, which is preferable for sufficiently exhibiting the effect corresponding to the first aspect. . Also, when performing maintenance, release the fixing with the fixture, and partially peel off the floor carpet from the floor panel to ensure the maintainability of various wirings arranged on the floor panel, etc. This is also preferable.

  The seal member is previously integrated with the lower surface of the floor carpet (corresponding to claim 4). In this case, when the floor carpet is laid on the floor panel, the seal member is automatically positioned at a predetermined position, and the assembly can be facilitated.

  Each of the sealing member and the pressing member is previously integrated with the lower surface of the floor carpet (corresponding to claim 5). In this case, when the floor carpet is laid on the floor panel, the sealing member and the pressing member are automatically positioned at predetermined positions, so that assembly can be facilitated.

On the vehicle body side, a flat portion having a flat upper surface is formed at a position where the seal member is in close contact,
The seal member is in close contact with the flat portion;
(Corresponding to claim 6). In this case, it is preferable to sufficiently secure the adhesion of the sealing member to the floor panel, that is, the sealing property and sufficiently enhance the sound insulation effect.

  The flat portion is formed by partially forming a shoulder portion with respect to the strength member located at the floor panel or a peripheral portion thereof (corresponding to claim 7). In this case, the flat portion can be formed by a simple method of forming the shoulder portion.

  The sealing member is formed of a foam rubber-based sealing material (corresponding to claim 8). In this case, what is preferable as a sealing member for ensuring sufficient adhesion (sealing performance) by receiving a pressing force while ensuring sealing performance for a long period of time is provided.

  According to the present invention, the sound insulation from the floor panel can be improved without unnecessarily increasing the mass and density of the floor carpet.

The top view which shows the floor panel part of the vehicle with which this invention is applied. The top view which shows an example of the floor carpet in the state which abbreviate | omitted the press member. The bottom view which looked at the floor carpet shown in FIG. 2 from the lower surface side. FIG. 4 is a cross-sectional view corresponding to line X4-X4 in FIG. 3. The cross-sectional perspective view which shows a part of floor panel before floor carpet laying. Sectional perspective view corresponding to FIG. 5 in the state which laid the floor carpet shown in FIGS. 2-4 on the floor panel. Side surface sectional drawing which shows the attachment state of the floor carpet in the cross member vicinity. The cross-sectional perspective view which shows the attachment state in the front-end part vicinity of a floor carpet. Side surface sectional drawing which shows the attachment state in the front-end part vicinity of a floor carpet. Sectional drawing which shows another example of attachment of a floor carpet. Sectional drawing which shows another example of attachment of a floor carpet. The figure which shows the effect of this invention illustratively.

  In FIG. 1, reference numeral 1 denotes a floor panel that constitutes a passenger compartment floor, which is for a vehicle having two rows of front and rear seats. A rear floor panel 3 is connected to a rear portion of the floor panel 1 via a kick-up portion 2. At the center of the floor panel 1 in the vehicle width direction, a tunnel portion 4 is formed that is a strength portion that bulges upward and extends in the front-rear direction. And the vehicle width direction edge part of the floor panel 1 is joined to the side sill 5 as a strength member extended in the front-back direction. In the figure, 6 is a pair of left and right front frames, and 7 is a dash panel that partitions the engine room and the vehicle compartment.

  On the floor panel 1, three sets of cross members 11 to 13 extending in the vehicle width direction are joined. The front cross member 11 is located in the vicinity of the boundary between the floor panel 1 and the dash panel 7 (near the foot of the driver seated in the driver's seat), and connects the tunnel portion 4 and the side sill 5. The cross member 12 is configured such that a front seat is attached, and connects the tunnel portion 4 and the side sill 5. The rear cross member 13 is adapted to be attached with a rear seat, and connects the tunnel portion 4 and the side sill 5.

  The side sill 5 serves as a strength member, and a closed cross-sectional space is formed therein. Similarly, the cross members 11 to 13 serving as strength members cooperate with the floor panel 1 to form a closed sectional space.

  The floor panel 1 is divided into a total of six substantially flat floor pan portions 1A to 1F in front, rear, left and right by the tunnel portion 4 and the cross members 11 to 13 described above. The floor pan portions 1A to 1C are positioned on the left side of the tunnel portion 4, while the floor pan portions 1D to 1F are formed on the right side of the tunnel portion 4. Although each floor pan part 1A-1F is slightly uneven, it is substantially flat and becomes a part where road noise from the road surface is easily transmitted to the vehicle interior.

  As shown in FIGS. 2 to 4, the floor carpet 20 is a single sheet in the embodiment, and is laid so as to cover almost the entire area of the floor panel 1 from above. For this reason, it is set as the bulging part 20a bulged so that it may protrude upwards in the position corresponding to the tunnel part 4 and the cross members 11-13. 2 to 4, a pressing member to be described later is not shown.

  The floor carpet 20 has an airtight skin layer 20A and a sound absorbing layer 20B made of a sound absorbing material integrated on the lower surface of the skin layer 20A. The sound absorbing layer 20B has a skin layer in a form separated into a plurality (six in the embodiment) so as to be positioned at positions corresponding to the plurality of (six in the embodiment) floor pan portions 1A to 1F described above. It is fixed to the lower surface of 20A. The shape of each sound absorption layer 20B is formed in a square shape corresponding to the shape in which the floor pan portions 1A to 1F are square.

  The skin layer 20A is, for example, a surface layer set on the upper surface of a base sheet layer having a rubber-based hermeticity (airtightness). Generally, the skin layer 20A has a sealing property. What is necessary is just to have a thin sealing sheet layer in the side etc. The skin layer 20A is a layer located on the upper surface side of the sound absorbing layer 20B, and may be a single layer or a plurality of layers. In addition, the sound absorbing layer 20B can be made of any suitable material such as a fiber material that is entangled and integrated, but in the embodiment, the sound absorbing layer 20B is configured using recycled fibers of a PET bottle. The thickness of the sound absorbing layer 20B is about 15 mm to 20 mm, and the thickness and weight of the floor carpet 20 including the skin layer 20A are the same as conventional inexpensive floor carpets (floor carpets for popular cars and intermediate cars). It is about the same as.

  A seal member 30 is further integrated on the lower surface of the skin layer 20A so as to surround each sound absorbing layer 20B (for example, integration using a double-sided tape). Each sealing member 30 is formed as a rectangular ring so as to surround the entire periphery of the corresponding sound absorbing layer 20B. The sealing member 30 has elasticity and adhesion, and is formed of, for example, a foam rubber-based sealing material.

  As shown in FIGS. 6 to 9, the floor carpet 20 is detachably fixed to the floor panel 1 using a rigid pressing member 40 made of metal or hard synthetic resin. Note that only a part of the skin layer 1A is shown in FIG. 6, and is omitted in FIG. At the time of fixing, the seal member 30 is pressed (contacted) against the floor panel 1 via the pressing member 40. That is, when the floor carpet 20 is fixed, the space between the skin layer 20A and the floor panel 1 (the floor pan portions 1A to 1F) (that is, the space portion where the sound absorbing layer 20B is located) is formed by the seal member 30. It is a sealed structure. The pressing member 40 is integrated with the floor carpet 20 in advance as will be described later. In addition, according to experiment, the sealing degree which can obtain the effect of the present invention can be obtained by applying a pressure of 10 kPa or more to the lower surface of the seal member 30 in the floor vertical direction.

  Next, an example of fixing the floor carpet 20 using the pressing member 40 will be described. First, as the pressing member 40 integrated with the floor carpet 20, as shown in FIGS. 6 and 8, there is one that is integrated with respect to the left and right edges extending in the front-rear direction of the sealing member 30. . That is, one end portion of the pressing member 40 is extended into the seal member 30 and integrated with the floor carpet 20 via the seal member 30. The other end of the pressing member 40 extends further outward from the outer peripheral edge of the floor carpet 20 (skin layer 20 </ b> A) and is fixed by the fixture 50. The fixing position of the fixing device 50 is the tunnel portion 4 at the inner side portion in the vehicle width direction and the side sill 5 at the outer side portion in the vehicle width direction.

  In addition, as shown in FIG. 7, the pressing member 40 integrated in advance with the floor carpet 20 may be fixed to the cross member 12 or 13. That is, the pressing member 40 is disposed so as to straddle the cross member 12 (the same applies to 13), and the front end portion and the rear end portion thereof are respectively extended and integrated in the seal member 30, while the front-rear direction The intermediate portion is fixed to the cross member 12 by the fixing tool 50.

  Furthermore, as the pressing member 40 integrated with the floor carpet 20 in advance, for example, there are cases as shown in FIGS. That is, the rear end portion of the pressing member 40 is extended and integrated in the seal member 30 provided at the front end portion of the floor carpet 20, and the front end portion is fixed to the cross member 11 by the fixing tool 50. ing.

  As shown in FIG. 9, at the front end of the floor carpet 20, the skin layer 20A extends long forward. That is, from the front end portion of the floor panel 1 to the lower end portion of the dash panel 7, a pedal such as an accelerator pedal, a brake pedal, or a clutch pedal is disposed. A cushioning material 45 is provided to ensure cushioning and the like of the person's feet. The cushion material 45 is made of, for example, a plate-like foamed polystyrene, and is integrated with the floor carpet 20 in advance (see, for example, FIG. 3). The skin layer 20 </ b> A of the floor carpet 20 is disposed so as to cover the cushion material 45. In FIG. 9, reference numeral 51 denotes a fixture for fixing the skin layer 20 </ b> A including the cushion material 45 to the floor panel 1 side.

  Here, as shown in FIG. 5, a portion of the floor panel 1 to which the seal member 30 is in close contact is partially a flat portion (flat surface), and this flat portion is denoted by reference numeral 1a. By forming the flat portion 1a, the adhesion between the seal member 30 and the floor panel 1 is more sufficiently secured.

  10 and 11 each show a modification of the present invention. In the case of FIG. 10, when the vehicle body side part to which the seal member 30 is in close contact is configured as a flat part, the shoulder part is formed on the member at the peripheral part. That is, the flat portion 4a is formed by forming the shoulder portion in the tunnel portion 4, while the flat portion 5a is formed by forming the shoulder portion on the side sill 5 at the same height position as the flat portion 4a. . In addition, although illustration is abbreviate | omitted, also in the cross members 11-13, the flat part by such shoulder formation can also be formed. In the figure, reference numeral 55 denotes a trim material.

  In the example of FIG. 11, in the floor pan portions 1 </ b> A to 1 </ b> F of the floor panel 1, a bulging portion is formed so that a peripheral portion thereof is partially convex upward, whereby the sealing member 30 is in close contact 1b is formed.

  FIG. 12 illustrates the effect of the present invention. The horizontal axis represents the vibration frequency, and the vertical axis represents the vibration transmission loss (the greater the transmission loss, the higher the quietness in the passenger compartment). In FIG. 12, the alternate long and short dash line indicates the state when a conventional general floor carpet is used, and the solid line indicates the case of the present invention. As is apparent from FIG. 12, in the present invention, the transmission loss can be sufficiently increased, and the transmission loss can be extremely increased particularly in the region of 500 Hz or higher.

  Although the embodiments have been described above, the present invention is not limited to the embodiments, and appropriate modifications can be made within the scope of the claims. For example, the floor carpet 20 may be divided into two left and right sections with the tunnel portion 4 as a boundary, or may be configured to be divided for each floor pan portion 1A to 1F. Can be appropriately selected. After the floor carpet 20 is laid on the floor panel 1, the pressing member 40 may be fixed to the vehicle body side so as to press the sealing member 30 later. The sealing member 30 may be an adhesive. In this case, a sealed structure can be secured without using the pressing member 40 separately.

  The present invention is preferable in enhancing the sound insulation effect by effectively using the floor carpet.

1: Floor panel 1A-1F: Floor pan part 1a: Flat part (FIG. 5)
1b: Flat part (FIG. 11)
4: Tunnel part 4a: Flat part (FIG. 10)
5: Side sill 5a: Flat part (FIG. 10)
7: Dash panels 11-13: Cross member 20: Floor carpet 20A: Skin layer 20B: Sound absorbing layer 30: Seal member 40: Pressing member 45: Cushion material 50: Fixing tool (for fixing pressing member)

Claims (8)

A sound insulation structure of a passenger compartment floor in which a floor carpet is laid on a floor panel constituting the passenger compartment floor surface,
The floor carpet has an airtight skin layer, and a sound absorbing layer made of a cushioning material disposed on the lower surface side of the skin layer to form an air circulation layer,
The space between the skin layer and the floor panel is sealed by a sealing member, and the portion where the sound absorbing layer is located between the skin layer and the floor panel has a sealed structure.
A sound insulation structure for the passenger compartment floor. In claim 1,
The floor panel is formed so as to have a plurality of substantially flat floor pan portions divided into front, rear, left and right,
The seal member is provided for each of the plurality of floor pan portions so as to surround a peripheral portion of each floor pan portion.
A sound insulation structure for the passenger compartment floor. In claim 1 or claim 2,
The sound insulation of the passenger compartment floor, wherein the seal member is pressed against the floor panel by a pressing member that is detachably fixed to the floor panel or a vehicle body strength member in the vicinity thereof by a fixture. Construction. In any one of Claims 1 thru | or 3,
The sound insulation structure for a passenger compartment floor, wherein the seal member is integrated with a lower surface of the floor carpet in advance. In claim 3,
The sound insulation structure for a passenger compartment floor, wherein the seal member and the pressing member are respectively integrated with a lower surface of the floor carpet in advance. In claim 4 or claim 5,
On the vehicle body side, a flat portion having a flat upper surface is formed at a position where the seal member is in close contact,
The seal member is in close contact with the flat portion;
A sound insulation structure for the passenger compartment floor. In claim 6,
The sound insulation structure for a passenger compartment floor, wherein the flat portion is formed by partially forming a shoulder portion with respect to the strength member located at the floor panel or a peripheral portion thereof. In any one of Claim 3, Claim 5 thru | or 6,
The sound insulation structure for a passenger compartment floor, wherein the seal member is formed of a foam rubber-based seal material.

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