JP2022108104A - Sound insulating structure of vehicle - Google Patents

Abstract

To provide a sound insulating structure of vehicle which improves quietness within a passenger compartment without appreciably hindering closure operability of a door.SOLUTION: A sound insulating structure of a vehicle 1 is the structure for sealing a space between a rear door 6 and a peripheral part 40 of a door opening part 4 of a car body 2 by means of a weather strip 10. The rear door 6 has a door main body 7 and is provided with the weather strip 10 on a portion of a peripheral part of the door main body 7. The peripheral part 40 of the door opening part 4 includes a first opening wall part 42a which is elongated in a car width direction and a second opening wall part 42b which is elongated in a vehicle longitudinal direction from an end part of the car outer side of the first opening wall part 42a. The sound insulating structure satisfies relations of 10 mm≤L1≤40 mm and L1>L2×1.07 when an abutting length along a car width direction as an abutting length of the weather strip 10 and the first opening wall part 42a is L1, and an abutting length along the longitudinal direction as the abutting length of the weather strip 10 and the second opening wall part 42b is L2.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a vehicle sound insulation structure in which sound insulation is achieved by sealing a space between a vehicle door and a peripheral edge of a door opening with a weatherstrip.

2. Description of the Related Art An elongated sealing member called a weatherstrip is provided on the outer edge of a vehicle door for the purpose of preventing water and sound from entering from outside the vehicle. When the door is closed, the weatherstrip is sandwiched between the outer edge of the door and the peripheral edge of the door opening of the vehicle body to seal between the door and the vehicle body in a watertight and airtight manner. This prevents water and sound from entering the passenger compartment. For example, Patent Literature 1 discloses an example of a vehicle provided with a weatherstrip. Specifically, it discloses a vehicle provided with a weatherstrip that is excellent in sealing performance during high-pressure water washing.

JP-A-11-11157

In recent years, from the viewpoint of improving the quietness of the vehicle interior, the components that make up the vehicle are regarded as panels that have an internal space, and by controlling the behavior of the air in that internal space, the transmitted sound from the outside to the inside of the vehicle is reduced. Research is underway to For example, a vehicle door can be said to be a double-walled panel composed of an outer panel and an inner panel. Therefore, it is thought that controlling the behavior of the air in the interior space of the door improves the quietness of the vehicle interior.

The inventors of the present application focused on the weatherstrip as an element that controls the behavior of the air in the interior space of the vehicle door, and found that increasing the support rigidity of the door with the weatherstrip is effective in reducing transmitted sound. I got some insight. However, simply increasing the rigidity of the weatherstrip by hardening it makes it difficult to close the door, which is likely to cause a so-called ajar door.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique capable of improving the quietness in the passenger compartment without significantly impairing the operability when the door is closed. and

The inventors of the present application have found that increasing the support rigidity of the weatherstrip (the rigidity of the weatherstrip that supports the door) is effective in reducing transmitted sound. In a structure in which a weatherstrip seals between a door provided with a strip and the periphery of the door opening of the vehicle body, as will be described later in detail, the contact state of the weatherstrip against the periphery when the door is closed is It has been found that the supporting rigidity is affected, and that the supporting rigidity is remarkably increased in a specific contact state.

The present invention is made based on this finding. That is, a sound insulation structure for a vehicle according to one aspect of the present invention includes a door provided with a weatherstrip, and a vehicle body having a door opening. A sound insulation structure for a vehicle in which a space is sealed by the weatherstrip, wherein the door has a door body including at least two plate members, inner and outer, with a space formed between the plate members, the door body The weather strip is provided on at least a part of the peripheral edge of the door opening, and the peripheral edge of the door opening includes a first surface portion extending along a first direction that is the width direction or the front-rear direction of the vehicle, and the first surface portion and a second surface portion extending in a second direction along the vehicle outer side surface from the vehicle outer end in the first direction of the contact length between the weatherstrip and the first surface portion in the door closed state Let L1 be the length of contact along the first direction, and L2 be the length of contact between the weatherstrip and the second surface along the second direction, It is characterized by satisfying the relationship of 10 mm≦L1≦40 mm and L1>L2×1.07.

According to this sound insulation structure, since 10 mm≦L1≦40 mm and the relationship of L1>L2×1.07 is satisfied, the support rigidity of the weatherstrip is ensured, and the quietness in the passenger compartment can be improved. becomes possible. In other words, L1 and L2 are elements that affect the support rigidity of the weatherstrip when the door is closed. up to. Moreover, since the supporting rigidity of the weatherstrip can be ensured without hardening the weatherstrip, the operability of closing the door is less likely to be hindered. The reaction force that the door receives from the weatherstrip when the door is closed is a factor that affects the closing operability of the door, and the reaction force increases as L2 becomes relatively larger. However, in this sound insulation structure, it is only necessary to satisfy the above relationship, and the degree of freedom of L2 is relatively high. Therefore, by setting L2 within a range that does not hinder the operability when the door is closed, it is possible to improve the quietness in the passenger compartment without significantly impairing the operability when the door is closed.

This sound insulation structure WHEREIN: It is suitable for the said 1st surface part to have extended in the direction parallel to the said 1st direction.

According to this structure, the frictional force generated between the weatherstrip and the first surface during the door closing operation is reduced compared to the case where the first surface portion is not parallel to the first direction. Therefore, it becomes difficult for the frictional force to hinder the operability when the door is closed.

In the above sound insulation structure, the two plate members are joined to each other at the outer edge of the door body. In the closed state, it is preferable that the second surface portion is located on the inner side of the door body.

According to this structure, the component that vibrates the door body from the portion corresponding to L2 of the weatherstrip is mainly transmitted to the interior plate of the two interior and exterior plates that form the space, and is transmitted to the interior of the vehicle. It is possible to suppress radiation sound. Therefore, it is possible to improve the quietness in the passenger compartment to a higher degree.

In the above sound insulation structure, the weatherstrip includes a hollow seal portion that abuts from the first surface portion to the second surface portion by being compressed and deformed when the door is closed. The length is such that the seal portion abuts on the first surface portion and the second surface portion.

According to this structure, the weatherstrip can be brought into close contact with the first surface portion and the second surface portion, which contributes to an increase in supporting rigidity of the weatherstrip.

In this case, it is preferable that the seal portion has a constricted portion recessed toward the inside of the seal portion at a position closer to the vehicle interior side in the first direction than the center of the cross section of the seal portion.

According to this structure, it is possible to compress and deform the position weather strip (seal portion) inside the vehicle more smoothly and with good reproducibility as the door is closed. This makes it possible to stably secure the contact area of the weatherstrip with respect to the first surface portion, that is, to stably secure L1.

Moreover, it is preferable that the seal portion has a constricted portion recessed toward the inside of the seal portion at a position on the vehicle outer side in the first direction from the cross-sectional center of the seal portion.

According to this structure, it is possible to compress and deform the weatherstrip (seal) at a position on the outside of the vehicle more smoothly and with good reproducibility as the door is closed. As a result, it is possible to stably secure the contact area of the weatherstrip with respect to the second surface portion, that is, to stably secure L2.

In addition, in the above sound insulation structure, it is preferable that the doors are doors for getting on and off that are provided on both left and right sides of the vehicle.

According to this structure, it is possible to effectively suppress the incidence of sound from both the left and right sides of a vehicle such as an automobile, thereby contributing to an improvement in the quietness of the interior of the vehicle.

In this case, if the door body is provided with an impact bar between the two plate members, the longitudinal end of the impact bar is adjacent to the weatherstripping in the vicinity of the peripheral edge of the door body. It is preferably provided in position.

According to this structure, by arranging the impact bar near the area where the weatherstrip exists, the rigidity of the door in the vicinity is increased, and it is possible to further suppress the radiated sound of the door.

As described above, according to the vehicle sound insulation structure of the present invention, the quietness in the vehicle interior can be improved without significantly impairing the operability when the door is closed.

FIG. 1 is a left side view of a vehicle according to an embodiment of the invention (vehicle to which the sound insulation structure of the invention is applied). FIG. 2 is a vehicle cross-sectional view (cross-sectional view taken along the line II-II in FIG. 1) near the rear end portion of the vehicle with the rear door closed. FIG. 3 is a cross-sectional view of the vehicle near the rear end of the rear door (the same location as in FIG. 1) immediately before the rear door is closed. FIG. 4 is a diagram showing a model of a rear door supported by a vehicle body. FIG. 5 is a diagram showing the state of motion of the panel of the model. (a) shows the state of motion when spring constant Kw>spring constant Ks, and (b) the state of motion when spring constant Kw<spring constant Ks. indicates FIG. 6 is a schematic front view of a test apparatus used in a weatherstrip support stiffness measurement test. FIG. 7 is a bottom view of the plate of the test apparatus; 8A and 8B are schematic diagrams showing the essential parts of the test apparatus, in which FIG. 8A shows the initial state, and FIG. 8B shows the test apparatus after the support has been moved from the initial state. FIG. 9 is a graph showing the relationship between the contact ratio and the support stiffness of the weatherstrip. FIG. 10 is a graph showing the relationship between contact ratio and sound insulation characteristics. FIG. 11 is a cross-sectional view of the vehicle near the rear end of the rear door (corresponding to FIG. 2), showing a phenomenon that occurs when L1 is 40 mm or more. FIG. 12 is a cross-sectional view of the vehicle in the vicinity of the rear end portion of the rear door (the portion corresponding to FIG. 2) of the vehicle according to the comparative example.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a left side view of a vehicle 1 (vehicle to which the sound insulation structure of the invention is applied) according to an embodiment of the invention. A vehicle 1 is an automobile, and includes a vehicle body 2, and a front door 5 and a rear door 6 mounted on both left and right sides thereof. The front door 5 and the rear door 6 correspond to the "door" of the present invention. The front door 5 and the rear door 6 are rotatably attached to the vehicle body 2 via hinges (not shown). As a result, the front door opening 3 (passenger entrance) formed on the side surface of the vehicle body 2 is opened and closed by the front door 5 , and the rear door opening 4 is opened and closed by the rear door 6 .

Door weatherstripping 10 (hereinafter abbreviated as weatherstripping 10) is attached to each of the outer edge portions of the front door 5 and the rear door 6 on the inside surface of the vehicle. When the door is closed, the weather strip 10 is sandwiched between the front door 5 and the peripheral edge of the door opening 3 on the front side to seal the gap between the front door 5 and the vehicle body 2. - 特許庁Similarly, a weatherstrip 10 is sandwiched between the rear door 6 and the periphery of the door opening 4 to seal the gap between the rear door 6 and the vehicle body 2 . As a result, water and sound are prevented from entering the passenger compartment.

The sealing structure of the front door 5 and the rear door 6 by such a weather strip 10 corresponds to the "sound insulation structure" of the present invention. Hereinafter, the sound insulation structure of the vehicle 1 will be described in detail, taking the rear door 6 on the left side of the vehicle shown in FIG. 1 as an example. In the following description, front/rear, left/right, and up/down directions are based on the vehicle 1 unless otherwise specified. For example, front and rear are synonymous with front and rear of the vehicle 1 , and left and right are synonymous with left and right of the vehicle 1 . Note that the left-right direction may be referred to as the vehicle width direction.

[Details of sound insulation structure]
The rear door 6 has a door body 7 forming a substantially lower half portion and a window frame 8 forming a substantially upper half portion. A front end portion of the door body 7 is attached to the vehicle body 2 via the hinge. The rear door 6 is provided with a window glass 9 that can be moved up and down, and the door body 7 accommodates a window regulator and rails (not shown) for driving the window glass 9 up and down.

The weather strip 10 is provided along the outer edge of the door body 7 . A weatherstrip 10 is provided along the outer edge of the door body 7 . The specific location and range where the weatherstrip 10 is provided differs depending on the specific structures of the door body 7 and the vehicle body 2 . In this example, a weatherstrip 10 is provided over the lower edge (lower side) and the rear edge (rear side) of the outer edge of the door body 7 . Incidentally, in the case of the front door 5, the weather strip 10 is provided only on the lower edge portion (lower side portion) of the outer edge portion of the door body.

FIG. 2 is a cross-sectional view of the vicinity of the rear end of the rear door of the vehicle 1 with the rear door 6 closed (cross-sectional view taken along the line II-II in FIG. 1), and FIG. 3 is the vehicle just before the rear door 6 is closed. 1 is a cross-sectional view of the vicinity of the rear end of the rear door (the same location as in FIG. 2). The white arrow in FIG. 3 indicates the closing operation direction of the rear door 6, and when the door is closed, the state shown in FIG. 3 changes to the state shown in FIG. 2 in chronological order.

The door body 7 of the rear door 6 includes an outer panel 32 made of a press-molded product forming the outside of the vehicle (the outside of the vehicle), an inner panel 34 made of the press-forming product forming the inside of the vehicle (the inside of the vehicle), and both panels 32 . , 34 and extending in the fore-and-aft direction. The outer panel 32 and the inner panel 34 correspond to "two plates" of the present invention, and are made of, for example, steel plates. The impact bar 36 is a steel rod-shaped reinforcing member assembled to the door body 7 to ensure crush resistance against side impact.

The outer panel 32 and the inner panel 34 are joined to each other by adhesion and hemming at the outer edge of the door body 7 (reference numeral 33 indicates the joint between the panels 32 and 34). Specifically, as shown in FIGS. 2 and 3, at the outer edge of the door body 7 (rear edge in FIGS. 2 and 3), the outer edge of the outer panel 32 and the outer edge of the inner panel 34 (overlapping portion described later) 35a) are overlapped and fixed to each other with an adhesive such as acrylic resin. Further, the outer edge portion of the outer panel 32 is folded back approximately 180 degrees so as to include a part of the outer edge portion (overlapping portion 35a) of the inner panel 34, so that the outer edge portion of the inner panel 34 is sandwiched by the outer panel 32 in the thickness direction. ing. As a result, the outer panel 32 and the inner panel 34 are joined together at their outer edge portions.

The outer panel 32 extends substantially linearly in the longitudinal direction of the vehicle 1 . The outer edge of the door body 7 of the inner panel 34 is joined to the outer panel 32 as described above, and most of the rest is formed so as to be separated from the outer panel 32 toward the vehicle interior. That is, it can be said that the door body 7 has a double wall structure in which a gap (internal space Sp) is formed between the outer panel 32 and the inner panel 34 .

The inner panel 34 includes an overlapping portion 35a superimposed on the outer edge portion of the outer panel 32, and a first wall portion 35b extending from the end (the front end in FIG. 2) of the overlapping portion 35a toward the vehicle interior so as to separate from the outer panel 32. , a second wall portion 35c extending from the end portion (the right end in FIG. 2) of the first wall portion 35b on the inside of the vehicle along the inner panel 34 toward the inner side of the door body (the front side in FIG. 2), and the second wall portion 35c. a third wall portion 35d extending toward the vehicle interior side from the end portion on the inside side of the door body; and a fourth wall portion 35e. It should be noted that the "door main body inner side" additionally means the side of the central portion of the door main body 7 in a side view (FIG. 1).

As described above, the overlapped portion 35a is adhered to the outer panel 32, and its end portion is sandwiched by the outer panel 32 in the thickness direction by the hemming process.

The impact bar 36 is fixed along the vehicle-interior side surface of the outer panel 32 in the interior space Sp of the door body 7 . As described above, the impact bar 36 extends in the front-rear direction, and the end of the impact bar 36 is provided at a position adjacent to the weatherstripping 10 (to be described later) with the inner panel 34 interposed therebetween, as shown in FIG. there is

On the other hand, as shown in FIGS. 2 and 3, a peripheral edge portion 40 of the door opening portion 4 of the vehicle body 2 is provided with a vehicle width opening facing the third wall portion 35d of the door body 7 with the rear door 6 closed. A first opening wall portion 42a in a direction (corresponding to the "first direction" of the present invention), and an outward direction along the outer surface of the vehicle body 2 from the outer end of the first opening wall portion 42a, that is, front and rear. A second opening wall portion 42b is provided that extends outward (rearward in FIG. 2) from the opening portion 4 in a direction (corresponding to the "second direction" of the present invention).

As shown in FIG. 2, the first opening wall portion 42a is inclined with respect to a straight line Lw extending in the vehicle width direction. Specifically, it is inclined so as to approach the door main body 7 as it goes from the outside to the inside of the vehicle. The second opening wall portion 42b extends slightly obliquely outward from the end portion of the first opening wall portion 42a. In this example, the first opening wall portion 42a corresponds to the "first surface portion" of the present invention, and the second opening wall portion 42b corresponds to the "second surface portion" of the present invention.

The end (rear end in FIG. 2) of the second opening wall portion 42b is constantly connected to the outer wall portion 44 forming the left outer surface of the vehicle body 2, and the state in which the rear door 6 is closed (hereinafter simply referred to as the door closed state or When the door is closed), the outer surface of the outer wall portion 44 and the outer surface of the outer panel 32 of the door body 7 jointly form the left side surface of the vehicle 1 .

In the vehicle 1 described above, when the door is closed, as shown in FIG. 2, an end portion P1 on the inner side of the door body (the front side in FIG. 2) at the joint portion 33 between the outer panel 32 and the inner panel 34 of the door body 7 is located on the inner side of the door body with respect to the end portion P2 of the second opening wall portion 42b on the inner side of the door body. That is, the end portion P1 of the joint portion 33 on the inner side of the door body is located on the inner side of the door body with respect to the second opening wall portion 42b.

The weatherstrip 10 is attached to the outer surface (rear surface in FIG. 2) of the third wall portion 35d of the inner panel 34 of the rear door 6 (door body 7). The weatherstrip 10 is an elongated rubber member formed by extrusion.

As shown in FIG. 3, the weatherstrip 10 includes a mounting base portion 14 which is a portion fixed to the door body 7, and is integrally formed with the mounting base portion 14 so as to abut against a peripheral edge portion 40 of the door opening 4. A hollow seal portion 12 (corresponding to the “seal portion” of the present invention) having a loop-shaped cross section is provided along the longitudinal direction.

The mounting base portion 14 is made of, for example, an ethylene propylene diene rubber (EPDM) solid material, and the hollow seal portion 12 is made of, for example, an EPDM sponge material. Note that the material forming the weatherstrip 10 is not limited to EPDM, and rubber materials other than EPDM, thermoplastic resins, and the like can also be used as long as the supporting rigidity described later can be ensured.

The mounting base portion 14 includes a bottom wall base portion 14a along the third wall portion 35d and a vehicle-exterior side wall base portion 14b extending from the vehicle-exterior end portion of the bottom wall base portion 14a to the side opposite to the third wall portion 35d (rear side in FIG. 3). and a vehicle-interior side wall base portion 14c extending from the vehicle-interior end portion of the bottom wall base portion 14a toward the side opposite to the third wall portion 35d. Each distal end of the vehicle-exterior side wall base portion 14 b and the vehicle-inside side wall base portion 14 c is connected to the hollow seal portion 12 . Thus, a space surrounded by the bottom wall base portion 14a, the vehicle-exterior side wall base portion 14b, and the vehicle-inside side wall base portion 14c is formed between the mounting base portion 14 and the hollow seal portion 12. As shown in FIG.

A plurality of through holes are provided in the bottom wall base portion 14a at predetermined intervals in the longitudinal direction thereof. Clips 16 are inserted through these through holes. The clip 16 is inserted and locked into a locking hole formed in the third wall portion 35d of the inner panel 34. As shown in FIG. Thereby, the weatherstrip 10 is fixed to the door body 7 . More specifically, as shown in FIG. 3, in a state in which the vehicle-exterior end of the bottom wall base portion 14a is in contact with the second wall portion 35c of the inner panel 34, the vehicle-exterior end of the third wall portion 35d of the inner panel 34 is pressed. A weatherstrip 10 is fixed at a position near the part. A lip portion 14d projecting outward is formed on the vehicle-exterior side wall base portion 14b of the mounting base portion 14, and the lip portion 14d abuts on the second wall portion 35c of the inner panel 34. As shown in FIG.

As shown in FIG. 3, the hollow seal portion 12 has a door-side seal portion 12a located on the inner panel 34 side and a vehicle body-side seal portion 12b on the opposite side, and is generally an oval elongated in the vehicle width direction. It has a shaped cross section. The hollow seal portion 12 is connected to the mounting base portion 14 via the door side seal portion 12a, and the vehicle body side seal portion 12b abuts against the peripheral edge portion 40 of the door opening portion 4 of the vehicle body 2 when the door is closed. The hollow seal portion 12 has the same shape and thickness along the longitudinal direction of the weatherstrip 10 . In addition, at the top of the hollow seal portion 12, that is, at the end portion on the outer side of the vehicle and the end portion on the inner side of the vehicle with respect to the cross-sectional center of the hollow seal portion 12, there are recessed toward the inside of the hollow seal portion 12 and extending in the longitudinal direction. Represented constrictions 13a, 13b are provided. As a result, when the door is closed, the hollow seal portion 12 is compressed and deformed starting from the constricted portions 13a and 13b.

When the rear door 6 is closed from the door open state shown in FIG. 3, the hollow seal portion 12 of the weatherstrip 10 is pressed against the peripheral edge portion 40 of the door opening 4 of the vehicle body 2 as shown in FIG. The hollow seal portion 12 abuts on the peripheral portion 40 from the first opening wall portion 42a to the second opening wall portion 42b. As a result, the space between the rear door 6 and the peripheral portion 40 is sealed in a watertight and airtight manner, thereby suppressing water and sound from entering the passenger compartment.

Here, as shown in FIG. 2, the length of contact between the weatherstrip 10 (hollow seal portion 12) and the first opening wall portion 42a of the peripheral edge portion 40 in the door closed state is the length along the vehicle width direction. Let L1 be the length, and L2 be the contact length between the weatherstrip 10 (hollow seal portion 12) and the second opening wall portion 42b along the longitudinal direction.
L1>L2×1.07 (1)
10 mm ≤ L1 ≤ 40 mm (2)
satisfy the relationship By adopting such a structure, in the vehicle 1, quietness in the vehicle interior is improved without significantly impairing operability when the door is closed. The reason why such a structure is adopted will be described in detail below.

As described above, the rear door 6 (door body 7) can be said to be a panel with a double-wall structure having a gap (internal space Sp) between the outer panel 32 and the inner panel . By controlling the behavior of the air in the internal space Sp, the double-structured panel can reduce transmitted sound that is transmitted from the outside of the vehicle to the inside of the vehicle. Based on this point of view, the inventors of the present application focused on the weatherstrip 10 as an element for controlling the behavior of the air in the interior space Sp of the rear door 6 . In other words, the inventors focused on the point that transmitted sound can be reduced by increasing the support rigidity of the weatherstrip 10 . Here, this principle will be described with reference to FIG.

FIG. 4 is a diagram showing a model of the rear door 6 supported by the vehicle body 2. As shown in FIG. In this model, the outer panel 32 and the inner panel 34 are joined via a spring B1 (spring constant Kw), and the rear door 6 is supported by the vehicle body 2 via a spring B2 (spring constant Ks). The spring B<b>1 corresponds to a joining element that joins the outer panel 32 and the inner panel 34 , such as an adhesive or a hem portion that joins the outer panel 32 and the inner panel 34 . The spring B2 corresponds to a support element such as the weatherstrip 10 or the hinge, which supports the rear door 6 to the vehicle body 2 when the door is closed.

A double-walled panel having an internal space provides a high sound insulation effect by independently moving the two panels with respect to incident sound energy (exciting force). This is because the independent movement of the two panels produces the effect of sound energy being reflected by each panel (obtaining a two-time reflection effect). Therefore, even in the case of a double-walled panel having an internal space, if the panels move together, the panel as a whole can only achieve a single reflection effect, and a high sound insulation effect cannot be expected.

Here, in the model of FIG. 4, when Kw>>Ks, the spring B2 expands and contracts more easily than the spring B1 against the incident sound (exciting force) from the outside of the vehicle. Therefore, as shown in FIG. 5(a), the outer panel 32 and the inner panel 34 move together, that is, the entire rear door 6 moves together. In this case, as shown in the figure, the rear door 6 as a whole can achieve only one reflection effect, and the sound insulation effect is not so high.

On the other hand, when Kw<<Ks, the spring B1 expands and contracts more easily than the spring B2 with respect to the incident sound. Therefore, as shown in FIG. 5(b), the outer panel 32 is displaced more greatly with respect to the inner panel 34, and the outer panel 32 and the inner panel 34 move independently of each other. In this case, as shown in the figure, since a reflection effect is obtained for each panel, a higher sound insulation effect can be obtained than in the case of Kw>>Ks.

In view of the above, the inventors of the present application have considered increasing the rigidity of the weatherstrip 10 to reduce transmitted sound. As a result of intensive studies, it was found that the contact state of the weatherstrip 10 against the peripheral edge 40 of the door opening 4 of the vehicle body 2 affects the support rigidity. Based on the fact that the ratio (L1/L2) affects the support stiffness of the weatherstrip 10, and based on the weatherstrip support stiffness measurement test described below, the ratio between L1 and L2 (hereinafter referred to as the abutment ratio) is predetermined. It was found that when the value is greater than or equal to the predetermined value, the supporting rigidity of the weatherstrip 10 is remarkably increased compared to when the value is less than the predetermined value.

FIG. 6 schematically shows a test apparatus for a weatherstrip support stiffness measurement test. Reference numeral 50 in FIG. 6 denotes a plate 50 imitating a door, which is supported by a mechanism (not shown) so as to be movable in the vertical direction (Z direction). The plate 50 is a rectangular metal plate elongated in the X direction. Two acceleration sensors 52a and 52b (a first acceleration sensor 52a and a second acceleration sensor 52b) are fixed to the lower surface 50a of the plate 50. As shown in FIG. As shown in FIG. 7, the acceleration sensors 52a and 52b are arranged at symmetrical positions equidistant from the center O of the plate 50 in the Y direction.

Rubber tubes corresponding to weather strips are arranged at both ends of the plate 50 in the X direction. Specifically, a large-diameter tube 55a for supporting the plate 50 from the outside in the X direction (side surface 50b side) and a small-diameter tube 55b for supporting the plate 50 from below (lower surface 50a side) are arranged. there is Each tube 55a, 55b extends in the Y direction along the side of the plate 50. As shown in FIG. A pair of large and small tubes 55a and 55b arranged on one side of the plate 50 respectively correspond to the weatherstripping 10 described above. That is, the large-diameter tube 55a corresponds to the portion of the weatherstrip 10 that contacts the first opening wall portion 42a, and the small-diameter tube 55b corresponds to the portion that contacts the second opening wall portion 42b. A pair of tubes 55a and 55b are supported by a common support base 60 via brackets, and are integrally movable in the horizontal direction by a moving mechanism (not shown).

In the support stiffness measurement test of the weatherstrip, first, the test apparatus was set in the initial state. In the initial state, as shown in FIG. 8A, the plate 50 (side surface 50b) contacts only the small-diameter tube 55b, and the small-diameter tube 55b contacts the plate 50 (side surface 50b) along the X direction. The small-diameter tube 55b is crushed so that the length L2' becomes a predetermined length. In this initial state, the vibration frequency of the plate 50 is changed while vibrating the plate 50, and the vibration acceleration of the plate 50 is measured by the acceleration sensors 52a and 52b. It was detected as a resonance frequency at positions 52a and 52b. For convenience, the position of the first acceleration sensor 52a is referred to as the first detection position, and the position of the second acceleration sensor 52b is referred to as the second detection position.

Next, as shown in FIG. 8B, while maintaining the contact state (contact length L2') between the small-diameter tube 55b and the plate 50, the large-diameter tube 55a is moved against the plate 50 (side surface 50b). The support bases 60 are moved toward each other so that the contact length L' along the Z direction becomes a predetermined length. asked for

Thereafter, each support base 60 was moved while the contact state between the small-diameter tube 55b and the plate 50 was maintained, that is, while L2' was kept constant, and the resonance frequency of the plate 50 was detected in the same manner as described above. . In this way, each support base 60 is moved to change the ratio of L1′ and L2′ (contact ratio=L1′/L2′), and six contact state samples with different contact ratios (second 1st to 6th samples), the resonance frequencies were detected at the first and second detection positions. At this time, the resonance frequency was detected three times for each sample.

Then, based on the resonance frequency of each sample detected as described above, the support stiffness of the tubes 55a and 55b that simulate the weatherstrip was obtained based on the following relational expression that defines the relationship between the resonance frequency and stiffness.

f=[1/(2π)]×(2k/m) ^0.5
where "f" is the resonant frequency, "k" is the stiffness (spring constant), and "m" is the mass of the plate 50.

FIG. 9 is a graph showing the results of the support stiffness measurement test, that is, a graph showing the relationship between the contact ratio (L1'/L2') and the support stiffness. References S1 to S6 indicating plot groups in the graph correspond to the six samples already described. That is, the group of plots denoted by symbol S1 shows the relationship between the contact ratio and the support stiffness of the first sample (initial state), and the group of plots denoted by symbols S2 to S6 represent the contact ratios of the second to sixth samples. The relationship between the ratio and the support stiffness is shown respectively. A plot of "black circles" indicates the support stiffness based on the measurement results at the first detection position, and a plot of "white squares" indicates the support stiffness based on the measurement results at the second detection position. Note that when the same value is detected multiple times in one sample, any overlapping plots are omitted from the illustration. In addition, the values of the abutment ratio plotted for each sample show variations, but this is due to errors in deformation of the tubes 55a and 55b.

As shown in FIG. 9, the support stiffness of each of the first to sixth samples is generally the same up to the vicinity of the contact ratio of 0.0 to 1.0, and there is no significant difference. However, when the abutment ratio is around 1.0 or more, more precisely 1.07 or more, the support rigidity is significantly higher than when it is less than that. As described above, the large-diameter tube 55a corresponds to the portion of the weatherstrip 10 that contacts the first opening wall portion 42a, and the small-diameter tube 55b corresponds to the portion of the weatherstrip 10 that contacts the second opening wall portion 42b. Equivalent to. That is, the contact length L1' between the large-diameter tube 55a and the plate 50 (lower surface 50a) corresponds to the contact length L1 between the hollow seal portion 12 of the weatherstrip 10 and the first opening wall portion 42a. The contact length L2' between the tube 55b and the plate 50 (side surface 50b) corresponds to the contact length L2 between the hollow seal portion 12 of the weatherstrip 10 and the second opening wall portion 42b.

Therefore, by setting the contact ratio to 1.07 or more for the actual weatherstrip 10, the support rigidity of the weatherstrip 10 can be increased. It is considered that the reflection effect of the sound becomes easier to obtain. FIG. 10 is a graph showing the verification results, that is, a graph showing the relationship between the contact ratio and the sound insulation characteristics.

In the verification, although not shown in the figure, a double-walled panel resembling a door was fixed through a weatherstrip between the sound source part and the sound receiving part, and the sound emitted from the speaker (sound source) of the sound source part. was performed by receiving the sound with the microphone of the sound receiving part.

The verification results shown in FIG. 10 substantially correspond to the support stiffness results shown in FIG. In other words, there is generally no big difference in the vicinity of the contact ratio between 0.0 and 1.0, but when the contact ratio is 1.07 or more, the sound insulation characteristics are significantly improved compared to when the contact ratio is less than 1.07. there is This is because when the abutment ratio is 1.07 or more, the supporting rigidity of the weatherstrip is increased compared to when it is less than that, so the sound produced by each panel constituting the door as shown in FIG. It can be considered that the reflection effect is remarkable. Therefore, it can be said that setting the contact ratio of the weatherstrip 10 to 1.07 or more is effective in enhancing the sound insulation characteristics and, in turn, in enhancing the quietness of the interior of the vehicle 1 . Based on the above findings, the vehicle 1 employs the structure defined by the above formula (1).

However, even if the contact ratio is set to 1.07 or more, if L1 is less than 10.0 mm, the weatherstrip 10 (hollow seal portion 12) with respect to the first opening wall portion 42a is absolutely The insufficient contact area tends to impair the basic sealing performance of the weatherstrip 10 . On the other hand, when L1 exceeds 40.0 mm, the frictional force between the hollow seal portion 12 (vehicle side seal portion 12b) and the first opening wall portion 42a increases when the rear door 6 is closed. As shown, wrinkles are likely to occur in the vehicle body side seal portion 12b. In such a state where wrinkles are generated in the vehicle body side seal portion 12b, it becomes difficult to achieve not only high support rigidity but also basic sealing performance. For the above reasons, the vehicle 1 employs the structure defined by the above formula (2) in addition to the structure defined by the above formula (1).

In the sound insulation structure of the vehicle 1, the weather strip 10 contacts the opening 4 (peripheral edge 40) of the vehicle body 2 as defined by the above equations (1) and (2). The supporting rigidity of the strip 10 is increased. Therefore, the weatherstrip 10 itself does not need to be rigidly provided, so that the quietness of the vehicle 1 can be improved without significantly impairing the closing operability of the rear door 6 .

[Effect]
As described above, the sound insulation structure of the vehicle 1 is a structure in which the weatherstrip 10 seals the space between the double-walled rear door 6 and the peripheral edge portion 40 of the door opening 4 of the vehicle body 2 . The peripheral edge portion 40 is provided with a first opening wall portion 42 a extending along the vehicle width direction and a second opening wall portion 42 b extending along the longitudinal direction of the vehicle 1 . In the closed state of the rear door 6, the contact length between the weatherstrip 10 (hollow seal portion 12) and the second opening wall portion 42b is L1, and the weatherstrip 10 (hollow seal portion 12) and the second opening wall portion 42b are L1. When the length of contact with L2 is L2, the relationship 10 mm≦L1≦40 mm and L1>L2×1.07 is satisfied.

According to such a sound insulation structure, as described above, it is possible to effectively increase the support rigidity of the weatherstrip 10, thereby improving the sound insulation characteristics of the rear door 6 and, in turn, improving the quietness of the vehicle interior. can be planned. Moreover, since the weatherstripping 10 is not rigidly provided, the supporting rigidity of the weatherstripping 10 can be increased, so that the operability of closing the door is less likely to be hindered. Therefore, it is possible to improve the quietness in the passenger compartment without significantly impairing the operability when the door is closed.

The reaction force received by the rear door 6 from the weatherstrip 10 when the rear door 6 is closed is a factor that affects the closing operability of the rear door 6, and the reaction force increases as L2 becomes relatively larger. However, in the sound insulation structure described above, since the above relationship should be satisfied in order to ensure the support rigidity of the weatherstrip 10, the degree of freedom for L2 is relatively high, and is within a range that does not hinder the operability when the door is closed. It is easy to set L2 to . Therefore, according to this sound insulation structure, it can be said that, in this respect as well, the quietness in the passenger compartment can be improved without significantly impairing the operability when the door is closed.

In the sound insulation structure of the vehicle 1, as shown in FIG. 2, when the door is closed, the inner side of the door body (front side in FIG. The end portion P1 is located on the inner side of the door body with respect to the second opening wall portion 42b. Therefore, the quietness in the passenger compartment can be further improved.

For example, as shown in FIG. 12, an end P1 of the joint portion 33 on the inner side of the door body is positioned closer to the door body than an end P2 of the second opening wall portion 42b on the inner side of the door body (front side in FIG. 2). A structure located on the outer side (rear side in FIG. 2) is also conceivable. However, in the case of this structure, as shown in the figure, the weatherstrip 10 (hollow seal portion 12) abuts only on the inner panel 34 at a position closer to the inside of the door body than the end portion P1. This state is likely to occur, and the component that vibrates the door body 7 at the portion L2 is likely to be transmitted mainly to the inner panel 34 and become radiated sound into the passenger compartment. On the other hand, according to the structure shown in FIG. 2, the weatherstrip 10 is likely to come into contact with the joint portion 33 of the inner panel 34, as shown in the same figure. In this case, the vibration component of the portion L2 that excites the door body 7 is more likely to be transmitted to the outer panel 32, thereby suppressing the radiated sound into the passenger compartment as described above. Therefore, it is possible to further improve the quietness in the passenger compartment.

In particular, in the sound insulation structure of the vehicle 1, the longitudinal end of the impact bar 36 is provided in the vicinity of the peripheral edge of the door body 7 and adjacent to the weatherstrip 10 with the inner panel 34 interposed therebetween. According to this structure, by arranging the impact bar 36 near the area where the weatherstrip 10 exists, the rigidity of the door body 7 in the vicinity is increased. Therefore, the radiation sound of the rear door 6 as described above can be effectively suppressed.

In the sound insulation structure of the vehicle 1, in the hollow seal portion 12 of the weatherstrip 10, a constriction extending in the longitudinal direction toward the inside of the hollow seal portion 12 is provided at a position closer to the inside of the vehicle than the central portion thereof. A portion 13a is formed. Further, in the hollow seal portion 12, a constricted portion 13b extending in the longitudinal direction by recessing toward the inside of the hollow seal portion 12 is formed at a position on the outer side of the vehicle relative to the central portion thereof.

According to this structure, when the rear door 6 is closed, the hollow seal portion 12 is sandwiched between the first opening wall portion 42a and the second opening wall portion 42b and the door body 7, and the predetermined opening as shown in FIG. It is possible to smoothly compress and deform the shape with good reproducibility. Therefore, it is possible to stably secure the contact area of the hollow seal portion 12 with respect to the first opening wall portion 42a and the second opening wall portion 42b, that is, to stably secure L1 and L2.

Although the structures of the rear door 6 and the door opening 4 have been described in the above embodiment, the structures of the front door 5 and the door opening 3 are basically the same as those of the rear door 6 and the door opening 4 described above. be. Therefore, the front door 5 and the door opening 3 can also enjoy the same effects as those described above.
[Modifications, etc.]
The sound insulation structure of the vehicle 1 described above is an example of a preferred embodiment of the sound insulation structure of the vehicle according to the present invention, and the specific structure can be changed as appropriate without departing from the gist of the present invention. For example, the following structure is also applicable.

(1) In the embodiment, the hollow seal portion 12 of the weatherstrip 10 has an elongated elliptical cross section in the vehicle width direction. However, the cross-sectional shape of the hollow seal portion 12 is not limited to an elliptical shape. With the rear door 6 closed, the cross-sectional shape allows the hollow seal portion 12 to appropriately contact the peripheral edge portion 40 of the door opening 4 from the first opening wall portion 42a to the second opening wall portion 42b. If it is Also, the portions forming L1 and L2 do not necessarily have to be hollow portions like the hollow seal portion 12 .

(2) In the embodiment, as shown in FIG. 2, the first opening wall portion 42a of the peripheral edge portion 40 is inclined forward by an angle θ with respect to the straight line Lw extending in the vehicle width direction. However, the first opening wall portion 42a may be parallel to the straight line Lw. In this case, the frictional force generated between the weatherstrip 10 (hollow seal portion 12) and the first opening wall portion 42a during the door closing operation is reduced compared to when the first opening wall portion 42a is inclined. Therefore, it can be said to be advantageous from the viewpoint of ensuring better closing operability of the rear door 6 . In addition, it can be said to be advantageous in suppressing the formation of wrinkles in the hollow seal portion 12 as shown in FIG. 11 .

(3) In the embodiment, the rear door 6 is provided with the weatherstripping 10 only on the portion extending over the lower edge (lower side) and the rear edge (rear side) of the door body 7, and the front door 5 is provided with the door body. A weatherstrip 10 is provided only on the lower edge (lower side) of the. However, the weatherstripping 10 may be provided over a wider area of the periphery of the door body 7 . The same applies to the front door 5 as well.

(4) In the embodiment, an example in which the present invention is applied to the front door 5 and the rear door 6 of the vehicle 1 has been described. It is also possible to apply the invention.

REFERENCE SIGNS LIST 1 vehicle 2 vehicle body 4 door opening 6 rear door 7 door body 10 door weather strip (weather strip)
REFERENCE SIGNS LIST 12 hollow seal portion 12a door side seal portion 12b vehicle body side seal portion 13a, 13b constricted portion 14 mounting base portion 32 outer panel (plate material)
33 joint part 34 inner panel (plate material)
36 impact bar 40 peripheral portion 42a first opening wall portion (first surface portion)
42b second opening wall (second surface)

Claims (8)

A sound insulation structure for a vehicle including a door provided with a weatherstrip and a vehicle body having a door opening formed thereon, wherein the weatherstrip seals between the door and at least a part of a peripheral edge of the door opening. There is
The door has a door body including at least two plate members and a space formed between the two plate members, and the weather strip is provided on at least a part of the peripheral edge of the door body,
The peripheral portion of the door opening includes a first surface portion extending along a first direction, which is the width direction or the front-rear direction of the vehicle, and an end portion of the first surface portion on the outside of the vehicle in the first direction. a second surface portion extending in a second direction along the side surface;
L1 is the length of contact between the weatherstrip and the first surface in the first direction when the door is closed, and the length of contact between the weatherstrip and the second surface is L1. and when the contact length along the second direction is L2,
10 mm≦L1≦40 mm and L1>L2×1.07
A sound insulation structure for a vehicle characterized by satisfying the relationship of In the vehicle sound insulation structure according to claim 1,
The sound insulation structure for a vehicle, wherein the first surface portion extends in a direction parallel to the first direction. In the vehicle sound insulation structure according to claim 1 or 2,
The two plate members are joined to each other at the outer edge of the door body,
In the joint portion between the plate members, an end portion on the inner side of the door body in the second direction is positioned further inward than the second surface portion on the inner side of the door body when the door is closed. Vehicle sound insulation structure. In the vehicle sound insulation structure according to any one of claims 1 to 3,
The weatherstrip is provided with a hollow seal portion that abuts from the first surface portion to the second surface portion by being compressed and deformed when the door is closed,
The sound insulation structure for a vehicle, wherein the lengths L1 and L2 are lengths at which the seal portion abuts on the first surface portion and the second surface portion. In the vehicle sound insulation structure according to claim 4,
The sound insulation structure for a vehicle, wherein the seal portion is provided with a constricted portion recessed inwardly of the seal portion at a position on the inner side of the vehicle in the first direction with respect to the cross-sectional center of the seal portion. In the vehicle sound insulation structure according to claim 4 or 5,
The sound insulation structure for a vehicle, wherein the seal portion includes a constricted portion recessed inwardly of the seal portion at a position on the outer side of the vehicle in the first direction with respect to the cross-sectional center of the seal portion. In the vehicle sound insulation structure according to any one of claims 1 to 6,
A sound insulation structure for a vehicle, wherein the doors are doors for getting in and out which are provided on both left and right sides of the vehicle. In the vehicle sound insulation structure according to claim 7,
The door body includes an impact bar between the two plate members,
A sound insulation structure for a vehicle, wherein a longitudinal end portion of the impact bar is provided at a position adjacent to the weatherstripping in the vicinity of the peripheral portion of the door body.

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