JP2022097073A - Seal member - Google Patents

Abstract

To provide a seal member which can be manufactured without using a molding die, has good followability and deformability along a curved shape of a wheel arch set as an attachment object, and can achieve high sealability.SOLUTION: A seal member 1 includes: a seal base part 2 which is bonded to an attachment surface 106 of a wheel arch of a motor vehicle through a double-sided tape 107; and a seal lip part 3 extending from one end part 2a of the seal base part 2. The seal base part 2 and the seal lip part 3 are integrally extruded along a longitudinal direction of the seal member 1 to be formed. The seal lip part 3, a main base part 4 forming a part of the seal base part 2 connected to the seal lip part 3, and a sub base part 5 which is the remaining part of the seal base part 2 separated from the seal lip part 3, are respectively formed of different materials.SELECTED DRAWING: Figure 5

Description

The present invention relates to a sealing member. More specifically, the present invention relates to a sealing member for a wheel arch, which is installed along a wheel arch of an automobile and has a sealing function capable of preventing water or the like from entering the inside of the vehicle.

Conventionally, a wheel arch 103 in which a part of the vehicle body 102 is cut out in a curved shape is generally provided according to the shape of the tire 101 of the automobile 100 (see FIG. 6). By providing such a wheel arch 103 on the vehicle body 102, a space 104 is formed between the tire 101 and the vehicle body 102, and the tire 101 can be easily replaced and the chain (not shown) can be easily attached and detached. be able to. Further, when the tire 101 is a steering wheel, even if the steering angle of the tire 101 changes according to the steering wheel operation, the tire 101 and the vehicle body 102 do not come into contact with each other.

However, when the space 104 is formed between the tire 101 and the vehicle body 102, rainwater, mud, or the like may easily enter the vehicle from the outside of the vehicle. Therefore, as shown in FIG. 6, a seal member 105 (wheel arch seal) for a wheel arch, which is mainly formed of a hard rubber material, is formed along the curved wheel arch 103 on the back side portion of the vehicle body 102 of the wheel arch 103. It is installed in this way.

As a general configuration, the seal member 105 has a seal base portion (not shown) that comes into contact with the mounting surface of the wheel arch 103 of the vehicle body 102, and projects from the seal base portion in a predetermined direction, and a part of the vehicle body 102 and the tip thereof are in contact with each other. It is provided with a contactable seal lip portion (not shown). This makes it possible to prevent rainwater and the like from entering the inside of the vehicle.

However, in the case of the conventional sealing member, there is a possibility that the following problems may occur. That is, in the case of a general seal member for a wheel arch, a rubber material such as ethylene-propylene-diene rubber (EPDM) that has been preheated to a predetermined temperature and is in a molten state is engraved based on the appearance shape of the seal member. It was mainly manufactured by pouring it into the cavity of the manufactured molding die and cooling and solidifying the rubber material in the molding die. That is, it was manufactured by a mold forming process using a molding die.

Therefore, it is necessary to prepare a plurality of molding dies in advance in order to manufacture a sealing member suitable for each of the vehicle type, the shape or size of the wheel arch to be installed, and the like. There is a problem that the initial cost (initial cost) until the start of manufacturing of the sealing member including the manufacturing cost of the molding die becomes high.

In addition, it goes through each process such as a step for pouring the molten rubber material into the molding die, a step for cooling and solidifying the rubber material, and a step for taking out the solidified sealing member from the molding die. It was necessary, and the work time required for each process could be increased.

Therefore, it may not be possible to manufacture a large number of sealing members in a short time, which may cause problems in terms of work efficiency and production efficiency, and may cause various problems such as complicated work process. .. In addition, there is a high possibility that so-called "burrs" are generally generated in the molded products manufactured by the molding die, and a burr removing step for removing the burrs may be required.

In the case of mold forming with a molding die, the sealed member to be manufactured is basically composed of one kind of material, for example, hard EPDM or the like. That is, the above-mentioned seal base portion and seal lip portion were integrally formed of the same material. However, it exhibits the characteristics required for the seal base portion, for example, the improvement of the strength of the entire seal member, the good mountability and adhesion to the mounting surface of the wheel arch, and the water blocking effect of the seal lip portion. In some cases, materials that conflict with each other are used.

More specifically, when trying to increase the strength of the seal member, it becomes difficult to deform the seal base portion along the curved shape of the wheel arch. In other words, the followability of the seal member to the curved shape of the wheel arch is reduced, a gap is created between the wheel arch and the seal member, sufficient adhesion cannot be maintained, and high sealability is obtained. There was a risk that it could not be done. On the other hand, if the deformability and followability of the seal member are used satisfactorily, the strength of the entire seal member may decrease. As a result, it was necessary to select a material such as a rubber material constituting the sealing member in consideration of the balance between strength and deformability.

Further, one end of the seal lip portion of the seal member is installed so as to be in contact with the vehicle body of the automobile. Therefore, when the seal lip portion is made of a hard rubber material, the vehicle body and the seal lip portion may come into point contact with each other, causing damage to the vehicle body due to vibration during traveling or the like. In addition, in the case of a hard rubber material, the specific gravity tends to be higher than that of other resin molded products, which may affect the weight increase of the entire vehicle of the automobile.

Therefore, in view of the above circumstances, the present invention can be manufactured without using a molding die, and has good followability and deformability along the curved shape of the wheel arch to be installed. However, it is an object of the present invention to provide a sealing member capable of exhibiting high sealing property (water-stopping property).

As a result of intensive research to solve the above problems, the present inventor has excellent followability and strength, and exhibits high sealing performance by manufacturing a sealing member using extrusion molding technology. We have found what is possible and have completed the present invention shown below.

[1] A seal member installed along the curved shape of a wheel arch of an automobile, the seal base portion abutting on the mounting surface of the wheel arch, and a seal extending from one end of the seal base portion. A lip portion is provided, and the seal base portion and the seal lip portion are formed by being integrally extruded along the longitudinal direction of the seal member, and are connected to the seal lip portion and the seal lip portion. A part of the seal base portion and the rest of the seal base portion separated from the seal lip portion are seal members made of different materials.

[2] The seal member according to the above [1], wherein a part of the seal lip portion and the seal base portion is made of a soft sponge material, and the rest of the seal base portion is made of a hard rubber material.

[3] The soft sponge material is a sponge-like ethylene-propylene-diene rubber made from ethylene-propylene-diene rubber, and the hard rubber material is a hard rubber made from the ethylene-propylene-diene rubber. 2] The seal member according to.

[4] The soft sponge material has a specific gravity in the range of 0.20 to 0.90 and a hardness in the range of 30 ° to 40 °, and the hard rubber material has a specific gravity in the range of 1.10 to 1.10. The specific gravity and the hardness value of the soft sponge material are both set smaller than those of the hard rubber material in the range of 1.60 and the hardness is in the range of 40 ° to 90 °. The sealing member according to [2] or [3].

[5] The seal member according to any one of the above [1] to [4], wherein the seal base portion further includes a plurality of notches formed at predetermined intervals along the longitudinal direction.

The seal member of the present invention is formed by integrally extruding materials having different properties by using extrusion molding technology, and has the properties of a part of the seal base portion, the rest of the seal base portion, and the seal lip portion. It is possible to exhibit high sealing performance while maintaining good followability along the curved shape of the wheel arch. In particular, it is possible to suppress the manufacturing cost required for manufacturing the molding die and reduce the initial cost in manufacturing the sealing member.

It is a reference perspective view which shows the schematic structure of the seal member of one Embodiment of this invention. It is a front view which shows the schematic structure of a seal member. It is a top view which shows the schematic structure of a seal member. It is a bottom view which shows the schematic structure of a seal member. FIG. 2 is an enlarged cross-sectional view taken along the line AA'in FIG. It is explanatory drawing which shows an example of the installation of the seal member with respect to a wheel arch.

Hereinafter, embodiments of the sealing member of the present invention will be described. The sealing member of the present invention is not limited to the following embodiments, and can be changed, modified, improved, or the like without departing from the gist of the present invention.

1. 1. Seal member As shown in FIGS. 1 to 5, the seal member 1 according to the embodiment of the present invention has a longitudinal shape, and a part of the vehicle body 102 is cut out in a curved shape according to the shape of the tire 101 of the automobile 100. It can be installed while being elastically deformed along the wheel arch 103 formed in the above. The configuration of the wheel arch 103 to be installed is substantially the same as that of FIG. 6 already described, and the same reference numerals are given, and detailed description thereof will be omitted here. Further, FIG. 5 also shows a configuration relating to the mounting surface 106 of the wheel arch 103 to be mounted and the double-sided tape 107 for attaching the sealing member 1 to the mounting surface 106.

The seal member 1 of the present embodiment has a seal base portion 2 that can come into contact with the mounting surface 106 (see FIG. 5) of the wheel arch 103, and a seal lip portion that extends from one end portion 2a of the seal base portion 2. It is mainly composed of 3 and the like. More specifically, the seal base portion 2 includes a main base portion 4 attached via the mounting surface 106 and the double-sided tape 107, and a sub-base portion 5 connected to the main base portion 4. .. That is, the seal base portion 2 is integrally configured by combining the two members of the main base portion 4 and the sub base portion 5.

Here, the main base portion 4 is a member exhibiting a substantially flat plate shape, while the sub base portion 5 is predetermined from the base body 6 of the sub base portion 5 so as to be able to come into contact with the mounting surface 106 by point contact. A pair of contact legs 7a and 7b projecting in a direction (corresponding to the downward direction on the paper surface in FIG. 5) and a direction opposite to the projecting direction of the contact legs 7a and 7b (in the upward direction on the paper surface in FIG. 5). It has a pair of convex portions 8a and 8b protruding from the corresponding). The heights of the contact legs 7a and 7b are set to be substantially the same as the tape thickness of the double-sided tape 107 to be attached and worn.

On the other hand, the seal lip portion 3 has a main lip portion 9 extending in a predetermined direction (corresponding to a substantially vertical upward direction in FIG. 5) from one end portion 2a of the seal base portion 2 (corresponding to one end of the main base portion 4). The first sub-lip portion 10 bent diagonally from the tip of the main lip portion 9 toward the sub-base portion 5, and the first sub-lip portion 10 obliquely toward the side further away from the sub-base portion 5 from the tip of the first sub-lip portion 10. It is provided with a second auxiliary lip portion 11 that is bent in a straight line. That is, the seal lip portion 3 has a cross-sectional shape that is bent in different directions at two locations. Further, as another configuration, the seal lip portion 3 includes a branched lip portion 12 that branches diagonally downward from the middle of the main lip portion 9 (see FIG. 5).

As shown in FIGS. 1 to 4, the seal member 1 of the present embodiment has a longitudinal shape, and the configuration related to the sub-base portion 5 of the seal base portion 2 described above is formed over the entire length in the longitudinal direction. It is not provided, but is provided on approximately half of the total length of the seal member 1 (right portion of the paper in FIG. 2). Only the main base portion 4 and the seal lip portion 3 of the seal base portion 2 described above are formed in the remaining portion of the seal member 1 (the left portion of the paper surface in FIG. 2). Further, a part of the main base portion 4 is provided with fixing holes 13 for fixing to the mounting surface 106 of the wheel arch 103 at two places.

Further, the seal base portion 2 is further provided with a plurality of notches 14 which are notched at predetermined intervals along the longitudinal direction of the sub-base portion 5 and are not provided with the sub-base portion 5. By having such a notch portion 14, the deformability of the sub-base portion 5 of the seal base portion becomes good.

As shown in FIG. 5, the seal member 1 of the present embodiment has a main base portion 4 corresponding to a part of the seal lip portion 3 and a seal base portion 2 connected to the seal lip portion 3, and a seal lip portion 3. The sub-base part 5 corresponding to the rest of the seal base part 2 understood from the above is made of different materials.

Specifically, in the seal member 1 of the present embodiment, the seal lip portion 3 and the main base portion 4 of the seal base portion 2 are made of ethylene-propylene-diene rubber as a raw material, have a plurality of voids inside, and have stress. It is formed of spongy ethylene-propylene-diene rubber (hereinafter referred to as "sponge EPDM") having the property of elastically deformable sponge. On the other hand, the sub-base portion 5 of the seal base portion 2 is made of a hard rubber made of ethylene-propylene-diene rubber (hereinafter, referred to as “hard rubber EPDM”) having the property of elastically deformable rubber with respect to stress. It is formed. The sponge EPDM corresponds to the soft sponge material in the present invention, and the hard rubber EPDM corresponds to the hard rubber material.

In the sealing member of the present invention, the soft sponge material is not limited to the above-mentioned ethylene-propylene-diene rubber, and the soft sponge material includes, for example, an olefin-based thermoplastic elastomer, a styrene-based thermoplastic elastomer, or other rubber. Materials, or other elastic materials with rubber-like elasticity can be mentioned. At that time, it may be partially or wholly composed of a solid material. On the other hand, examples of the hard rubber material include olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers, other rubber materials, and other elastic materials having rubber-like elasticity. At that time, it may be partially or wholly composed of a sponge-like material.

As described above, the seal member 1 of the present embodiment is formed by using two kinds of materials having different properties such as sponge EPDM and hard rubber EPDM. The sponge EPDM and the hard rubber EPDM are well-known materials used in the manufacture of resin molded parts for automobiles, and the details thereof will be omitted here.

In the seal member 1 of the present embodiment, the sponge EPDM, which is a soft sponge material, is adjusted so that its specific gravity is in the range of 0.20 to 0.90, preferably in the range of 0.45 to 0.75. Will be done. In addition, the hardness of the sponge EPDM is adjusted to be in the range of 30 ° to 40 °.

On the other hand, the hard rubber EPDM, which is a hard rubber material, is adjusted so that its specific gravity is in the range of 1.00 to 1.60, preferably in the range of 1.15 to 1.45. In addition, the hardness of the hard rubber EPDM is adjusted to be in the range of 40 ° to 90 °, preferably in the range of 65 ° to 75 °.

That is, the values of the specific gravity and the hardness of the sponge EPDM are set to be smaller than those of the hard rubber EPDM. As a result, the sub-base portion 5 of the seal base portion 2 that comes into contact with the wheel arch 103 via the contact legs 7a and 7b has a high specific gravity and hardness, and has sufficient strength required for the seal member 1. be able to.

As a result, the mounting state with respect to the wheel arch 103 is stabilized. In addition, as described above, the sub-base portion 5 is provided with a plurality of cutout portions 14 at predetermined intervals. Therefore, it is possible to sufficiently secure the deformability with respect to stress. As a result, when the seal member 1 is brought into contact with the seal member 1 while being elastically deformed along the curved wheel arch 103, the followability to the wheel arch 103 becomes good, and the mounting surface 106 of the wheel arch 103 and the seal member 1 (seal base portion). Good adhesion to 2).

As a result, it is possible to prevent rainwater or the like from entering the inside of the vehicle from between the wheel arch 103 and the seal member 1. That is, the effect of the sealing property (water stopping property) by the sealing member 1 can be enhanced.

On the other hand, for the main base portion 4 of the seal lip portion 3 and the seal base portion 2, sponge EPDM having a lower specific gravity and hardness than the hard rubber EPDM is used. As a result, the deformability that flexibly deforms with respect to stress is better than that of the sub-base portion 5 using the hard rubber EPDM. Therefore, it does not hinder the deformability of the curved wheel arch 103.

Further, the lip end portion 3a at the tip of the seal lip portion 3 may come into contact with a part of the vehicle body 102 and be elastically deformed in a state of being attached to the wheel arch 103. When it is formed only of a hard rubber material such as hard rubber EPDM as in the conventional sealing member 105 (see FIG. 5), when it comes into contact with the vehicle body 102, elastic deformation due to stress is slight due to the properties of the hard rubber. Therefore, it is in point contact with the vehicle body 102.

However, since the seal lip portion 3 of the seal member 1 of the present embodiment is made of a soft sponge material, the degree of deformation with respect to stress is larger than that of hard rubber, and the seal member 1 is greatly crushed and deformed by contact with the vehicle body 102. do. That is, it comes into surface contact with the vehicle body 102. As a result, it has the effect of reducing damage to the vehicle body 102 due to vibration or the like generated during traveling or the like. Further, by forming a part of the seal member 1 with sponge EPDM having a small specific gravity, the weight of the seal member 1 as a whole can be reduced.

As described above, the wheel arch 103 is formed by forming the seal lip portion 3, a part of the seal base portion 2, and the rest of the seal base portion 2 with two kinds of materials having different properties according to their respective characteristics. The followability to the curved shape is good, and the strength of the seal member 1 itself can be made sufficient. As a result, the sealing member 1 having a high sealing property to prevent the intrusion of rainwater and the like is formed. In addition, since "burrs" do not occur as compared with the case of using a conventional molding die, it is possible to omit the step of removing such burrs. That is, it is possible to reduce the man-hours in manufacturing the seal member.

2. 2. Method for Manufacturing Seal Member As described above, the seal member 1 of the present embodiment is manufactured by using two kinds of materials having different properties, such as sponge EPDM and hard rubber EPDM. At this time, in the production of the seal member 1, a technique of "coextrusion molding" in which two kinds of materials are simultaneously extruded from a molding base can be used. Such co-extrusion molding (or two-color extrusion molding) is well known in resin processing, rubber processing, etc., and simultaneously extrudes a hard material and a soft material, or simultaneously extrudes a transparent material and a coloring material. It is possible to change the properties of a specific part of the product.

More specifically, first, a molding base having a cross-sectional shape as shown in FIG. 5 is set in an extruder capable of coextrusion molding. On the other hand, sponge EPDM and hard rubber EPDM, which are heated and adjusted to an extrudable viscosity and are in a flowable state, are prepared in the two raw material supply units provided in the extruder. In this state, the sponge EPDM and the hard rubber EPDM are pressed from the two raw material supply units by a predetermined extrusion pressure, and the molding is simultaneously extruded from the molding base. At this time, by adjusting the extrusion pressures of the sponge EPDM and the hard rubber EPDM, the sponge EPDM and the hard rubber EPDM can be extruded into a predetermined position of the molding base. Thereby, the arrangement and ratio of the sponge EPDM and the hard rubber EPDM in the cross section of the seal member 1 can be made uniform.

The sponge EPDM and the hard rubber EPDM extruded from the molding base are cooled by coming into contact with the surrounding outside air and lose their fluidity. Then, it is cut after being extruded to a predetermined length (for example, about 500 mm). As a result, a long-shaped workpiece composed of two types of materials is formed. By performing Thomson punching on such a long-shaped workpiece, the above-mentioned fixing holes 13 and cutouts 14 and the like can be formed. As a result, the production of the seal member 1 of the present embodiment is completed. The Thomson punching process is a well-known processing method in which a processing material is pressed and punched using a Thomson mold in which a blade is embedded in a base plywood, and detailed description thereof will be omitted here.

The sealing member of the present invention can be applied to a wheel arch provided in a vehicle such as an automobile.

1,105: Seal member 2: Seal base part, 2a: One end part 3: Seal lip part, 3a: Lip end part 4: Main base part (part of seal base part), 5: Sub base part ( (Remaining part of the seal base part), 6: Base body, 7a, 7b: Contact leg part, 8a, 8b: Convex part, 9: Main lip part, 10: First sub lip part, 11: Second sub lip part, 12: Branch lip part, 13: Fixing hole, 14: Notch part, 100: Automobile, 101: Tire, 102: Body, 103: Wheel arch, 104: Space, 106: Installation surface, 107: Double-sided tape.

Claims (5)

It is a sealing member installed along the curved shape of the wheel arch of an automobile.
The seal base portion that comes into contact with the mounting surface of the wheel arch,
A seal lip portion extending from one end of the seal substrate portion is provided.
The seal base portion and the seal lip portion
Formed by being integrally extruded along the longitudinal direction of the sealing member,
The seal lip portion, a part of the seal base portion connected to the seal lip portion, and the rest of the seal base portion separated from the seal lip portion are
A sealing member made of different materials. A part of the seal lip portion and the seal base portion
Formed of soft sponge material,
The rest of the seal substrate is
The sealing member according to claim 1, which is made of a hard rubber material. The soft sponge material is
A sponge-like ethylene-propylene-diene rubber made from ethylene-propylene-diene rubber.
The hard rubber material is
The sealing member according to claim 2, which is a hard rubber made from the ethylene-propylene-diene rubber as a raw material. The soft sponge material is
The specific gravity is in the range of 0.20 to 0.90, and the hardness is in the range of 30 ° to 40 °.
The hard rubber material is
The specific gravity is in the range of 1.10 to 1.60, and the hardness is in the range of 40 ° to 90 °.
The sealing member according to claim 2 or 3, wherein both the specific gravity and the hardness value of the soft sponge material are set smaller than those of the hard rubber material. The sealing member according to any one of claims 1 to 4, further comprising a plurality of notches formed at predetermined intervals along the longitudinal direction of the wheel arch.

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