Weather strip

Abstract

To provide a weather strip which is excellent in transmitted sound reduction effect.SOLUTION: In a weather strip 200 which comprises a fitting base part 10 which is attached to opening / closing body 1 circumference or body 2 opening circumference of a vehicle and a hollow seal part 20 made of sponge rubber which is integrally formed to the fitting base part 10 and elastically contacts to the opening circumference of body 2 side or opening circumference of the opening / closing body 1 side when closing the opening / closing body 1 and on which a paint 50 is applied on surface, hardness of the paint 50 of the hollow seal part 20 is 40.0 Mpa or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a weather strip which is attached to the periphery of an opening / closing body such as an automobile side door, back door, trunk lid, or hood, or to the periphery of an opening in the body, and which elastically contacts the body side or the opening / closing body when the opening / closing body is closed, forming a seal between the opening / closing body and the body. [Background technology]

[0002] Conventionally, as shown in FIG. 7, a weather strip (door weather strip) 100 has been known which includes a mounting base 10 that is attached to the periphery of an opening / closing body 1 such as a vehicle door, and a hollow seal portion 20 made of sponge rubber that is integrally molded with the mounting base 10 and elastically contacts the periphery of the opening on the body 2 side when the opening / closing body 1 is closed (see, for example, Patent Document 1).

[0003] In such weather strip 100, if the sponge rubber material can be made to have a lower density, that is, a lower specific gravity, the amount of raw material required for the product can be reduced, which leads to resource conservation and is environmentally friendly. However, it is also known that when the specific gravity of the sponge rubber material is reduced, there is a tendency for the amount of sound transmitted through the hollow seal portion 20 from the exterior side to the interior side of the vehicle (hereinafter referred to as transmitted sound) to increase according to the mass law.

[0004] For example, it is known that the specific gravity of extrusion-molded sponge rubber used in door weather strips is generally in the range of 0.45 to 0.70. However, if a sponge rubber material with a specific gravity of 0.40 is used in order to further reduce weight, as shown in FIG. 8, the transmitted sound reduction performance drops significantly in the frequency range of 2000 to 4000 Hz, which is the frequency that has a large effect on the human ear, compared to sponge rubber with a specific gravity of 0.53 or 0.45.

[0005] In such a case, for example, by increasing the thickness of the hollow seal portion 20, the effect of reducing the transmitted sound can be obtained, but this is not preferable because it increases the compressive load of the weather strip and deteriorates the door closing ability. Another method for reducing transmitted sound is known, in which the hollow seal is made of a high-density sponge rubber material or solid rubber material (see, for example, Patent Document 2). Compared to a hollow seal made entirely of sponge rubber material, this method also has concerns about poor door closing due to increased compression load, and there is room for further improvement due to the increased cost caused by the use of multiple materials and the complex nozzle structure used for extrusion molding. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6470827 [Patent Document 2] Japanese Patent Application Publication No. 10-236163 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a weather strip that is excellent in the effect of reducing transmitted sound. [Means for solving the problem]

[0008] In order to achieve the above object, the weather strip of the present invention is a weather strip (200) including an attachment base (10) attached to the periphery of an opening / closing body (1) of a vehicle or the periphery of an opening of a body (2), and a seal part (20) made of sponge rubber and having a surface coated with paint (50) that is integrally formed with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, The hardness of the seal portion (20) is 40.0 MPa or more.

[0009] The present invention also provides a weather strip (200) including an attachment base (10) attached to the periphery of an opening / closing body (1) of a vehicle or the periphery of an opening of a body (2), and a seal part (20) made of sponge rubber and having a surface coated with paint (50) that is integrally molded with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, The sponge rubber has a specific gravity in the range of 0.30 to 0.55, The hardness of the seal portion (20) is 40.0 MPa or more.

[0010] The present invention also provides a weather strip (200) including an attachment base (10) attached to the periphery of an opening / closing body (1) of a vehicle or the periphery of an opening of a body (2), and a seal part (20) made of sponge rubber and having a surface coated with paint (50) that is integrally molded with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, The sponge rubber has a specific gravity in the range of 0.40 to 0.55, The hardness of the seal portion (20) is 40.0 MPa or more.

[0011] The present invention also provides a weather strip (200) including an attachment base (10) attached to the periphery of an opening / closing body (1) of a vehicle or the periphery of an opening of a body (2), and a seal part (20) made of sponge rubber and having a surface coated with paint (50) that is integrally molded with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, The hardness of the seal portion (20) is obtained from a relational expression between the hardness of the seal portion (20) and the transmitted sound, and is characterized in that the hardness is such that the transmitted sound is reduced by 1 dB or more.

[0012] The present invention also provides a weather strip (200) including an attachment base (10) attached to the periphery of an opening / closing body (1) of a vehicle or the periphery of an opening of a body (2), and a seal part (20) made of sponge rubber and having a surface coated with paint (50) that is integrally molded with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening / closing body (1) when the opening / closing body (1) is closed, The hardness of the sealing portion (20) is obtained from a relational equation between the hardness of the sealing portion (20) measured by a nanoindentation method and the transmitted sound, and is characterized in that the hardness reduces the transmitted sound by 1 dB or more.

[0013] The present invention also provides a paint (50) for an attachment base (10) attached to the periphery of an opening / closing body (1) or the periphery of an opening of a body (2) of a vehicle, and a weather strip (200) made of sponge rubber that is integrally molded with the attachment base (10) and elastically contacts the periphery of the opening of the body (2) or the periphery of the opening of the opening / closing body (1) when the opening / closing body (1) is closed, The paint (50) is characterized in that the hardness after drying is 40.0 MPa or more.

[0014] Note that symbols in parentheses indicate corresponding elements or matters described in the drawings and in the detailed description of the invention described below. Effect of the Invention

[0015] According to the present invention, in a weather strip comprising a mounting base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle, and a seal portion made of sponge rubber with a painted surface that is integrally molded with the mounting base and comes into elastic contact with the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, the hardness of the seal portion is set to 40.0 MPa or more, so that the transmitted sound through the seal portion can be reliably reduced by 1 dB or more.

[0016] That is, while surface treatments that simply apply paint to the surface of the sealing part of a weatherstrip have existed in the past, there has been no technology that focuses on the relationship between the hardness of the sealing part of an automotive weatherstrip and the transmitted sound through the sealing part. There has never been any idea that derives the relationship between the hardness and transmitted sound of the sealing part from a relational equation such as that shown in Figure 3, and sets the hardness of the sealing part, i.e., the hardness of the coating, to 40.0 MPa or more with clear awareness of reliably reducing the transmitted sound through the sealing part by 1 dB or more, and this is an extremely unique item.

[0017] In this case, the specific gravity of the sponge rubber constituting the sealing portion is in the range of 0.30 to 0.55, and more preferably, the specific gravity is in the range of 0.40 to 0.55. By making the specific gravity 0.40 or less, the weight of the weather strip can be reduced, the amount of raw material required for the product can be reduced, resource conservation can be achieved, and the product is environmentally friendly.

[0018] Furthermore, according to the present invention, the hardness of the sealing portion is obtained from the relational equation between the hardness of the sealing portion and transmitted sound, and is set to a hardness that reduces the transmitted sound by 1 dB or more, thereby enabling effective reduction in transmitted sound. Furthermore, the hardness of the seal portion can be accurately measured by the nano-indentation method. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a cross-sectional view showing a weather strip 200 according to an embodiment of the present invention. [Diagram 2] 2 is a cross-sectional view showing a state in which the weather strip 200 shown in FIG. 1 is bent. [Diagram 3] 1 is a graph showing the relationship between the hardness (MPa) of the seal portion and the transmitted sound OA value of 2000 to 4000 (dB). [Figure 4] This is a graph comparing the hardness of the seal portion measured using the nanoindentation method with a maximum indentation load of 100 μN, with the specific gravity of the sponge rubber that makes up the seal portion being changed. [Diagram 5] This is a graph comparing the hardness of the seal portion measured using the nanoindentation method with a maximum indentation load of 20 μN, with the specific gravity of the sponge rubber that makes up the seal portion being changed. [Figure 6] 1 is a graph showing the relationship between frequency and transmitted sound when the sponge rubber with a specific gravity of 0.40 that constitutes the seal portion is not coated with paint and when it is coated with the paint according to the present embodiment. [Figure 7] FIG. 11 is a cross-sectional view showing a bent state of a weather strip 100 according to a conventional example. [Figure 8]1 is a graph showing the relationship between wave number and transmitted sound when the specific gravity of the sponge rubber constituting the sealing portion is changed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] A weather strip 200 according to an embodiment of the present invention will be described with reference to FIGS. This weatherstrip 200, like the weatherstrip 100 (Figure 7) shown in the conventional example, comprises a mounting base 10 which is attached to the opening / closing body 1 of the vehicle, in this case the side door 1, and a hollow sealing portion 20 which is made of sponge rubber and has a surface coated with paint 50, and which is integrally molded with the mounting base 10 and comes into elastic contact with the periphery of the opening of the body 2 when the side door 1 is closed. The same components as those in the conventional example (FIG. 7) are given the same reference numerals. Also, the thickness of the paint 50 on the drawing is an image for ease of understanding, and the actual thickness of the paint is in μm (microns), while the thickness of the hollow seal portion 20 is in mm (millimeters), so the thickness of the paint is approximately 1 / 1000 of the thickness of the hollow seal portion 20.

[0021] The sponge rubber constituting the hollow seal portion 20 of the weather strip 200 according to the embodiment of the present invention has a specific gravity of 0.40. The hollow seal portion 20 is made of a rubber material mainly made of EPDM (ethylene propylene diene rubber), but is not limited to EPDM, and may be made of rubber materials mainly made of other synthetic rubbers or various thermoplastic elastomers.

[0022] A coating material 50 was used that would give the hollow seal portion 20 a hardness of 40.0 MPa or more. The reason why the paint 50 used here gives the hollow seal portion 20 a hardness of 40.0 MPa or more is that the transmitted sound through the hollow seal portion 20 is reduced by 1 dB or more.

[0023] This is obtained from the relational expression between the hardness of the hollow seal portion 20 made of sponge rubber with a specific gravity of 0.40 and the OA value (2000 to 4000 Hz) of the transmitted sound, as shown in FIG. Figure 3 shows five paints (samples A, B, C, D, and E) as shown in Table 1 were applied to the surface of the hollow seal portion 20, and then the hardness of the hollow seal portion 20 after the paint had dried was measured using the nanoindentation method.The OA (overall acoustic) values ​​of the transmitted sound through the hollow seal portion 20 corresponding to each hardness were then plotted, and a straight line approximating the plotted positions was determined using Microsoft Excel (hereinafter referred to as Excel). The transmitted sound was measured by clamping the weatherstrip 200 between two jigs not shown (for example, fixing the weatherstrip 200 to the lower jig and pressing the upper jig against the hollow seal portion 20 of the weatherstrip 200), and then introducing sound from one side of the hollow seal portion 20 (one side of the gap between the upper and lower jigs that sandwich the weatherstrip 200) and collecting the sound with a microphone on the other side (the other side of the gap between the upper and lower jigs that sandwich the weatherstrip 200).

[0024] The equation for the approximate straight line is Excel's approximate equation: y = -0.025x + 68.603 Coefficient of determination: R 2 =09169, and a high correlation was observed between the transmitted sound and the hardness of the hollow seal portion 20.

[0025] [Table 1]

[0026] The nanoindentation method is a method for evaluating hardness solely by calculation from physical quantities (load and indentation depth) measured by the device, and involves determining contact stiffness and contact depth, and then calculating hardness and Young's modulus. An indentation load (magnetic force) is generated by controlling the amount of current flowing through the electromagnetic coil, and the indenter is pressed into the paint sample from above to measure how much the sample is displaced (how easily the indenter can be pressed in).

[0027] In this embodiment, the tester (nanoindentation tester) was Anton Paar's "UNHT3" and the indenter was a Berkovich indenter. The maximum indentation load of the indenter was set to 20 μN, and the loading / unloading rate was set to 600 μN / min, and the test was performed in accordance with ISO14577. The hollow seal portion 20 was cut into a square of 10 mm in length and 10 mm in width, which was used as the measurement specimen. The thickness of the measurement specimen was about 1.8 mm. If the maximum indenter load was set to 100 μN, as shown in Figure 4, when the same paint was used, the values ​​changed significantly for specific gravities of 0.40, 0.44, and 0.55 due to the influence of the specific gravity of the sponge rubber that constitutes the hollow seal portion 20. However, as shown in Figure 5, when the maximum indenter load was set to 20 μN, the influence of specific gravity was extremely small, and the hardness could be measured with high accuracy.

[0028] According to the relational expression (y = -0.025x + 68.603) shown in FIG. 3, the hardness that reduces the transmitted sound by 1 dB or more is 1 (= 68.603 - 67.603) = 0.025x, so x = 40.0 MPa. In other words, when using paint 50 with a hardness of 40.0 MPa or more, the transmitted sound of the hollow seal portion 20 can be reduced by 1 dB or more.

[0029] For example, as shown in FIG. 6, when samples B, D, and E (Table 1) are applied to a hollow seal portion 20 made of sponge rubber with a specific gravity of 0.40, the transmitted sound reduction performance is significantly improved in the range of 2000 to 4000 Hz compared to a case with a specific gravity of 0.40 and no paint applied.

[0030] According to the weather strip 200 configured in this manner, the hollow seal portion 20, which is lightweight due to the use of sponge rubber with a specific gravity of 0.40, has a hardness of 40.0 MPa or more, so that the sound transmitted through the hollow seal portion 20 can be reliably reduced by 1 dB or more.

[0031] That is, while surface treatments in which paint is simply applied to the surface of the hollow seal portion 20 of a weatherstrip 200 have existed in the past, there has been no technology that focuses on the relationship between the hardness of the hollow seal portion 20 of an automotive weatherstrip 200 and the sound transmitted through the hollow seal portion 20. There has been no idea whatsoever of deriving the relationship between hardness and transmitted sound from a relational equation such as that shown in FIG. 3, and setting the hardness of the hollow seal portion 20 to 40.0 MPa or more with a clear awareness of ensuring a reduction in the sound transmitted through the hollow seal portion 20 by 1 dB or more, and this is an extremely unique point.

[0032] In this embodiment, an example has been shown in which paint 50 is applied to the surface of weatherstrip 200, in which hollow seal portion 20 is formed from sponge rubber material with a specific gravity of 0.40 in order to reduce weight, but the sound transmitted through hollow seal portion 20 can also be reliably reduced by 1 dB or more by applying paint 50 to the surface of weatherstrip 200 made of sponge rubber material with a specific gravity in the range of 0.30 to 0.55, more preferably, with a specific gravity in the range of 0.40 to 0.55.

[0033] In addition, the hardness of the hollow seal portion 20 measured by the nanoindentation method was used to obtain the relational expression between the hardness of the hollow seal portion 20 and the transmitted sound, but other hardness measurement methods may be used. In addition, the relational expression between the hardness of the hollow seal portion 20 and the transmitted sound was calculated from an approximation formula in Excel, but other methods may be used.

[0034] In this embodiment, the door weatherstrip 200 is attached along the periphery of the side door 1 and elastically contacts the periphery of the opening of the body 2, but the door weatherstrip may be attached along the periphery of the opening of the body 2 and elastically contacts the periphery of the side door 1 when the door is closed. The hollow seal portion 20 may be solid, such as a lip. The present invention is also applicable to any weatherstrip, such as a weatherstrip attached to an opening / closing body such as a back door, trunk lid, or hood of an automobile. [Explanation of symbols]

[0035] 1 Opening and closing body (side door) 2. Body 10 Mounting base 20 Hollow seal part 50 paint 100 Weatherstrip 200 Weather strip

Claims

1. A weather strip comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a seal part that is made of sponge rubber and has a painted surface and is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, A weather strip characterized in that the hardness of the seal portion is 40.0 MPa or more.

2. A weather strip comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a seal part that is made of sponge rubber and has a painted surface and is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, The sponge rubber has a specific gravity in the range of 0.30 to 0.55, A weather strip characterized in that the hardness of the seal portion is 40.0 MPa or more.

3. A weather strip comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a seal part that is made of sponge rubber and has a painted surface and is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, The sponge rubber has a specific gravity in the range of 0.40 to 0.55, A weather strip characterized in that the hardness of the seal portion is 40.0 MPa or more.

4. A weather strip comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a seal part that is made of sponge rubber and has a painted surface and is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, A weather strip characterized in that the hardness of the seal portion is obtained from a relational expression between the hardness of the seal portion and transmitted sound, and is a hardness that reduces transmitted sound by 1 dB or more.

5. A weather strip comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a seal part that is made of sponge rubber and has a painted surface and is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, The hardness of the sealing portion is obtained from a relational equation between the hardness of the sealing portion measured by a nanoindentation method and the transmitted sound, and is a hardness that reduces the transmitted sound by 1 dB or more.

6. A paint for a weather strip, comprising: an attachment base that is attached to the periphery of an opening / closing body or the periphery of a body opening of a vehicle; and a sponge rubber weather strip that is integrally formed with the attachment base and elastically contacts the periphery of the body opening or the periphery of the opening / closing body when the opening / closing body is closed, A paint for weather strips, characterized in that the paint has a hardness of 40.0 MPa or more after drying.

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