JP2000313050A - Gasket and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight gasket including a synthetic resin subjected to bending processing as a core material and a method for easily producing the same. SOLUTION: A gasket 1 consists of a core material 11 made of a synthetic resin, and the main body 19 made of a synthetic resin covering the core material 11. A core material molding process is performed by using a flat resin tape 10 having a flat plate-shaped cross section as a material of the core material 11, and applying bending processing to the flat resin tape 10 to mold the core material. An extrusion process is done for coating at least a part of the periphery of the molded core material with a synthetic resin material for the main body part 9 to integrally mold the core material 11 and the main body part 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a joint gasket and a method of manufacturing the same.

[0002]

2. Description of the Related Art For example, joints between exterior wall panels for houses,
The joint between the window glass and the body of the car is fitted with a gasket to close it. For example,
As shown in FIG. 28, the gasket 9 for housing is disposed at the joint 80 between the two outer wall panels 8 to prevent rainwater from entering the joint 80.

As shown in FIG. 27, this conventional gasket 9 includes a metal core 91 having a substantially U-shaped cross section,
It comprises a rubber main body 92 covering the core material 91. Further, a lip portion 921 is provided on the main body portion 92, so that the easiness of mounting is secured and the sealing property is improved.

[0004]

[Problems to be solved] By the way, the gasket 9
Usually, it is often used after being cut to an optimum length by site adjustment. However, it is not always easy to cut the gasket 9 because the core material 91 is made of metal. Further, the gasket 9 has a problem that the core material 91 is made of metal, so that the weight is heavy and the handling is not easy.

The core 91 is made of metal, while the main body 92 is made of rubber, and both have greatly different thermal expansion characteristics. Therefore, when the gasket 9 is used in an environment having a large temperature change, there is a problem that the difference in the amount of expansion and contraction between the core material 91 and the main body portion 92 reduces the adhesion between the two and affects the durability. May occur.

On the other hand, there are cases where it is desired to improve the strength characteristics of the gasket 9. In this case, for example, FIG.
As shown in FIG. 9A, a method of increasing the thickness of the metal core material 91, a method of locally increasing the thickness of the main body 92 as shown in FIG. . Although these measures are effective for improving strength,
This may cause a further increase in weight and an excessive increase in strength of unnecessary parts.

In order to solve these problems, the core material 9
There is an idea that a lightweight synthetic resin is used as the material 1 (for example, JP-A-61-225036). However, conventionally, it is not always easy to manufacture a lightweight gasket using a synthetic resin as a core material that is bent into a shape such as a substantially U-shaped cross section, and a processing method is not necessarily established.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide a lightweight gasket having a bent synthetic resin as a core material and a manufacturing method capable of easily manufacturing the gasket. Things.

[0009]

A first aspect of the present invention is a method of manufacturing a gasket including a synthetic resin core and a synthetic resin body covering the core. A core material forming step of forming a core material by applying a bending process to the flat resin tape using a tape as a material of the core material, and forming the main body portion on at least a part of the periphery of the formed core material; And an extruding step of integrally molding the core and the main body by coating the core with the synthetic resin material.

As the flat resin tape, for example, a thermoplastic resin can be used. Specifically, for example,
Various materials such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyamide, polyester, polycarbonate, polyacetal, and cellulose acetate can be used.

As the above-mentioned flat resin tape, phenol resin, vinyl ester resin, unsaturated polyester resin, epoxy resin, polyurethane resin and the like other than thermoplastic resin can be used.

As the flat resin tape, a tape having a flat cross section is used. The thickness and width dimensions can be appropriately selected according to the size of the gasket to be obtained. In addition, it is also possible to divert a generally used resin tape for packing to the flat resin tape.

In the core material forming step, a bending process is performed on the flat resin tape. As a method of performing bending, for example, there is a method of forming a roller using a pair of forming rollers, a method of using an insert nozzle described later, and the like.

The extruding step is performed by a conventionally known extruding method of covering the core with a synthetic resin material for the main body and integrally molding the core with the main body. be able to. In this case, it is not necessary to cover the entire circumference of the core material. This is because there is no need to consider corrosion of the core material.

As the synthetic resin material for the main body, a thermoplastic resin or a thermosetting resin can be used. Examples of the thermoplastic resin in this case include polyethylene, polypropylene, polyvinyl chloride, polystyrene, and polyester. Examples of the thermosetting resin include rubber materials such as silicone rubber, EPDM, styrene / butadiene rubber, and chloroprene; phenol resins; and unsaturated polyester resins.

Next, the operation of the present invention will be described. In the present invention, the flat resin tape is used as the core material. And for this flat resin tape,
A core material is formed by performing bending. for that reason,
The obtained gasket can be lighter in weight than a conventional gasket using metal as a core material. In addition, since the core material of the above gasket is a synthetic resin,
It can be easily cut at any position. Further, the difference in the coefficient of thermal expansion between the core material and the main body can be significantly reduced as compared with the related art. The resulting gasket is therefore very easy to handle.

As described above, according to the present invention, it is possible to provide a lightweight gasket using a bent synthetic resin as a core material and a manufacturing method capable of easily manufacturing the gasket.

Next, as in the second aspect of the present invention, a thin portion having a locally small thickness is previously provided on the flat resin tape, and the thin portion is formed by bending the thin portion in the core material forming step. Preferably, it is at a bending point. The thin portion of the flat resin tape can be formed by providing a concave recess on one or both surfaces of the flat resin tape. Further, the shape of the concave depression can be various shapes such as a semicircle, a triangle, and the like.

Since the thin portion has a locally reduced thickness, it has lower bending rigidity than its surroundings. for that reason,
The flat resin tape can be very easily bent using the thin portion as a bending point. In addition, by accurately setting the formation position of the thin portion, the bending position can be stabilized. Therefore, by using the flat resin tape having the thin portion, the core material can be easily and accurately formed into a bent shape such as a U-shaped cross section in the core material forming step.

Next, as in the third aspect of the invention, before the core material forming step, a thin part forming step of locally forming a thin part in the flat resin tape is performed, and
In the core material forming step, it is preferable to perform bending on the flat resin tape with the thin portion as a bending point.

The most remarkable point is that the thin portion is provided on the flat resin tape, and the bending is performed using the thin portion as a bending point.

In the thin part forming step, a thin part having a small thickness is locally formed on the flat resin tape. This thin portion can be formed by providing a concave depression on one or both surfaces of the flat resin tape in the same manner as described above. Further, the shape of the concave depression can be various shapes such as a semicircle, a triangle, and the like.

As a method of forming the thin portion, various methods such as a method of crushing using a pair of rollers after heating and a method of cutting can be employed as described later. Further, the thin portion can be provided at two or three or more positions in accordance with the cross-sectional shape of the core material to be obtained. It can also be provided symmetrically or asymmetrically.

It is preferable that the thin part forming step is continuously performed by incorporating the core material forming step and the extruding step into the above-described apparatus. In this case, the manufacturing process can be rationalized. On the other hand, it is of course possible to perform the thin-walled portion forming step discontinuously by a device separate from the device for performing the core material forming step and the extrusion step. After the thin portion forming step is performed in advance, the core material forming step and the extruding step can be performed using a flat resin tape having the thin portion.

Next, the function and effect of performing the above-described thin portion forming step will be described. In this case, the thin portion is provided in advance in the thin portion forming step on the flat resin tape at a portion where the bending process is performed. Since the thin portion has a locally reduced thickness, it has lower bending stiffness than its surroundings.

Therefore, the flat resin tape can be very easily bent using the thin portion as a bending point. In addition, by accurately setting the formation position of the thin portion, the bending position can be stabilized.
Therefore, in the core material forming step, the core material can be easily and accurately formed into a bent shape such as a U-shaped cross section. Therefore, a lightweight gasket using a bent synthetic resin as a core material can be easily manufactured.

Next, a thermoplastic resin is used as the flat resin tape, and in the thin portion forming step, at least a part of the flat resin tape is heated, It is preferable that the heating portion of the flat resin tape is pressed from both sides using a crushing roller, and at least one surface of the flat resin tape is crushed to form the thin portion. That is, it is preferable that the flattened resin tape is softened by the above-described heating, and then the flattened resin tape is nipped and pressed by the crushing roller. Thereby, the thin portion can be easily formed.

According to a fifth aspect of the present invention, the extruding step includes a molding die and an insert nozzle disposed upstream of the die, and the core material is inserted from inside the insert nozzle. The synthetic resin material is supplied to the die from the periphery of the insert nozzle, and the synthetic resin material is extruded from the die using an extruder. It is preferable to perform the process by passing the flat resin tape through a passage provided inside the nozzle so as to gradually change from a flat shape to a desired shape.

In this case, the core material forming step can be easily performed without providing a large-scale core material processing device as in the case where the conventional core material is made of metal. Further, by simply modifying the passage of the insert nozzle, the conventional extruder can be used as it is, and the equipment cost can be reduced.

A sixth aspect of the present invention is a gasket comprising a synthetic resin core, a synthetic resin body covering the core, and partially improving the rigidity of the core. Using a flat resin tape provided with a reinforcing portion in advance at a position corresponding to a part for improving the rigidity of the core material as a material of the core material, and bending the flat resin tape. A core material forming step of forming the core material, and covering at least a part of the periphery of the formed core material with the synthetic resin material for the main body portion, and integrally forming the core material and the main body portion. And an extruding step of molding.

The most remarkable point of the present invention is that a flat resin tape having a flat cross section is used as a material of the core material, and the reinforcing portion is provided in advance on the flat resin tape. . Various types of reinforcements can be used for the reinforcing part of the flat resin tape, such as a flat resin tape with a flat cross section and a locally narrow resin tape joined together, or a locally thick part integrally provided. There are things.

In the core material forming step, the core material having a bent shape such as a substantially U-shaped cross section is formed by applying a bending process to the flat resin tape. The bending in this case can be easily performed by, for example, previously heating and softening a portion of the flat resin tape to be bent. Further, as described later, the core material forming step can be performed after forming the thin portion.

Next, the operation of the present invention will be described. In the present invention, a flat resin tape having the reinforcing portion is used as a material of the core material. Therefore, by bending this flat resin tape, the reinforcing portion can be easily positioned at a place where the core material should be reinforced. Therefore, a reinforced core material can be easily obtained.

Further, the gasket is provided by changing the position of the reinforcing portion in the flat resin tape.
The reinforcing portion of the core material can be easily changed. Further, the core is made of a synthetic resin including the reinforcing portion. Therefore, the obtained gasket can also have the effects of being lightweight, easy to cut, having a small difference in thermal expansion with the main body, and being easy to handle, even after being reinforced.

As described above, by using the manufacturing method of the present invention, it is possible to easily manufacture a gasket in which an arbitrary portion is appropriately strengthened in accordance with the use of the gasket.

Next, a seventh aspect of the present invention comprises a synthetic resin core material, a synthetic resin body covering the core material, and partially improving the rigidity of the core material. A method of manufacturing a gasket, wherein a flat resin tape having a flat cross section is used as a material of the core material, and a reinforcing tape is attached to a reinforcing portion of the flat resin tape corresponding to a portion for improving the rigidity of the core material. Performing a tape reinforcing step, and then bending the flat resin tape to form the core material; and forming a synthetic resin for the main body on at least a part of the periphery of the formed core material. An extruding step of covering the material and integrally molding the core material and the main body with each other.

The most remarkable point of the present invention is to use a flat resin tape having a flat cross section as a material of the core material, and a tape reinforcing step of attaching the reinforcing tape to a reinforcing portion of the flat resin tape. It is to do.

In the tape reinforcing step, the reinforcing tape is attached to a reinforcing portion of the flat resin tape. In this case, for example, a tape obtained by cutting the flat resin tape into a narrow width can be used as the reinforcing tape as it is. Further, the thickness, width, material and the like of the reinforcing tape can be changed according to the degree of reinforcement.

In the tape reinforcing step, a method of attaching a reinforcing tape to the flat resin tape is as follows.
Various methods can be adopted. For example, there is a method using an adhesive, or a method using a characteristic of a thermoplastic resin and attaching after heating, as described later.

In the core material forming step, the core material having a bent shape such as a substantially U-shaped cross section is formed by bending the flat resin tape. The bending in this case can be easily performed by, for example, previously heating and softening a portion of the flat resin tape to be bent. Further, as described later, the core material forming step can be performed after forming the thin portion.

Next, the operation of the present invention will be described. In the present invention, the above-mentioned flat resin tape is used as a material of the above-mentioned core material, and the above-mentioned tape reinforcing step is performed on this. Thus, the core material obtained by bending the flat resin tape has a portion reinforced by the reinforcing tape. Therefore, the obtained gasket has a desired portion reinforced by the above-mentioned reinforcing tape.

In the gasket, the reinforcing portion can be easily changed by changing the attachment position of the reinforcing tape. Further, the degree of reinforcement can be adjusted by changing the thickness or rigidity of the reinforcing tape. Further, the core is made of a synthetic resin including the reinforcing portion. Therefore, the obtained gasket can also have the effects of being lightweight, easy to cut, having a small difference in thermal expansion with the main body, and being easy to handle, even after being reinforced.

As described above, by using the manufacturing method of the present invention, it is possible to easily manufacture a gasket in which an arbitrary portion is appropriately strengthened in accordance with the use of the gasket.

Next, a thin portion having a locally small thickness is previously provided on the flat resin tape, and the thin portion is formed by bending the thin portion in the core material forming step. Preferably, it is at a bending point. In this case, as described above, bending can be performed very easily. In addition, by accurately setting the formation position of the thin portion, the bending position can be stabilized.

According to a ninth aspect of the present invention, a thermoplastic resin is used as the flat resin tape and the reinforcing tape, and in the tape reinforcing step, at least one of the flat resin tape and the reinforcing tape is used. Is heated and softened, and then it is preferable to paste the two by overlapping and pressing. In this case, the flat resin tape and the reinforcing tape can be attached without using other materials such as an adhesive, and the tape reinforcing step can be performed very easily.

Further, prior to the core material forming step, a thin part forming step of locally forming a thin part in the flat resin tape is performed before the core material forming step. The core material forming step is preferably performed by bending the flat resin tape around the thin portion. In this case, as described above, the core material can be easily and accurately formed into a bent shape.

An eleventh aspect of the present invention is a gasket comprising a synthetic resin core material and a synthetic resin body covering the core material, wherein the core material is a flat plate having a flat cross section. A gasket is provided by bending a resin tape and forming a thin portion locally at a bending point of the bending process.

The most remarkable point in the present invention is that the thin portion is provided at the bending point of the bending of the core material. In this case, in the process of manufacturing the gasket, the work of bending the flat resin tape can be performed very easily and accurately. Therefore, the gasket is inexpensive and has excellent dimensional accuracy. In addition, as described above, since the core material is a synthetic resin, it is possible to obtain the effects of being lightweight, easy to cut, having a small difference in thermal expansion with the main body, and being easy to handle.

Next, a twelfth aspect of the present invention comprises a synthetic resin core material, a synthetic resin body covering the core material, and partially improving the rigidity of the core material. A gasket, characterized in that a reinforcing tape is attached to a reinforcing portion for improving the rigidity of the core material.

The most remarkable point of the present invention is that the reinforcing tape is attached to a reinforcing portion for improving the rigidity of the core material.

In this case, the core material can be easily reinforced by the presence of the reinforcing tape. Further, the degree of reinforcement can be easily adjusted by changing the thickness, rigidity, and the like of the reinforcing tape. Further, since the reinforcement is performed by the reinforcing tape, the production is very easy. In addition, the core member and its reinforcing portion can be made of a synthetic resin. In this case, it is possible to obtain the effects of light weight, easy cutting, small difference in thermal expansion with the main body, and easy handling. .

Next, as in the thirteenth aspect, in any one of the first, sixth and seventh aspects, before the core material forming step, the core material is formed along the longitudinal direction of the flat resin tape. A plurality of through-holes are continuously formed at predetermined intervals to maintain a predetermined interval, and in the core material forming step,
The bending process may be performed by using a line connecting the through holes as a bending point. In this case, since the bending can be performed with the bending point being on the line connecting the plurality of through holes provided in the drilling step, the bending in the core material forming step can be easily performed, and the bending can be easily performed. The processing position can be set accurately. Furthermore, by providing the through-hole, the synthetic resin material of the main body can be disposed in a state of being penetrated through the through-hole by performing a subsequent extrusion step, and the core material and the main body can be disposed. Can be strengthened.

According to a fourteenth aspect of the present invention, there is provided a gasket comprising a synthetic resin core and a synthetic resin body covering the core, wherein the core is a flat resin having a flat cross section. The gasket is characterized in that the tape is formed by bending and a plurality of through-holes are continuously provided at predetermined bending points at bending points.

In the gasket of the present invention, since a plurality of through holes are provided in the flat resin tape, the bending accuracy is high, the cost is low, and the dimensional accuracy is excellent. Since the synthetic resin of the main body enters the through hole, the connection between the main body and the core material is very strong. In addition, as described above, since the core material is a synthetic resin, it is possible to obtain the effects of being lightweight, easy to cut, having a small difference in thermal expansion with the main body, and being easy to handle.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A gasket according to an embodiment of the present invention and a method of manufacturing the gasket will be described with reference to FIGS. The gasket 1 of this embodiment is a gasket for a house, and includes a synthetic resin core 11 having a substantially U-shaped cross section and a rubber main body 19 covering the core 11. The core material 11 is formed by bending a flat-plate resin tape made of a thermoplastic resin into a substantially U-shaped cross-sectional shape, and has a locally thick portion at a bending point 12 of the bending process. Thin part 15
Is formed in advance.

The gasket 1 was manufactured as follows. That is, as shown in FIG. 2A, a flat resin tape 10 made of a thermoplastic resin and having a flat cross section is attached to the core material 11.
Was used as a material. Then, as shown in FIGS. 2B and 2C, a thin-walled portion forming step of locally forming a thin-walled portion 15 on the flat-plated resin tape 10, A core material forming step of forming the core material 11 having a substantially U-shaped cross-section by applying a bending process with a bending point as a bending point, and coating the rubber material for the main body part 19 around the formed core material 11. An extruding step of integrally molding the core 11 and the main body 19 was performed.

In executing this manufacturing method, a manufacturing apparatus 5 as shown in FIG. 3 was used. As shown in the figure, the manufacturing device 5 includes an uncoiler 51, a thin-wall portion forming device 5,
2. Extruder 53, vulcanization tank 54, cooling tank 55, take-off machine 5
6, a cutting machine 57 is provided.

As shown in FIGS. 4 to 6, the thin portion forming device 52 has two pairs of heating devices 521 and two pairs of crushing devices 525. As shown in FIGS. 4 and 5, the heating device 521 is configured by combining four hot jet devices 523 that blow hot air from a flat nozzle 522. The hot jet devices 523 are arranged on the upper and lower surfaces of two places of the flat resin tape 10, and hot air is blown from these hot jet devices 523 to locally heat the flat resin tape 10.

The crushing device 525 includes a pair of upper and lower crushing rollers 526 as shown in FIGS. Each of the crushing rollers 526 has a smooth circular arc shape on an end face. Further, two sets of crushing rollers 526 are arranged on the left and right in the width direction.
21 corresponds to the portion to be heated.

As shown in FIGS. 3 and 7, the extruder 53 has an extruder main body 531 and a head 53 provided at the end thereof.
It consists of two. The head section 532 has an insert nozzle 533 disposed therein and a base 535 disposed at the tip. The base 535 is fixed by a base presser 536.

The extruder 53 of this embodiment has the same basic configuration as the conventional one as described above, but the insert nozzle 533
Has undergone a special remodeling. That is, as shown in FIG. 8 and FIG.
The passage 534 is provided so as to gradually change from a flat plate shape to a desired U-shape. Other vulcanization tank 54, cooling tank 5
5, the take-off machine 56 and the cutting machine 57 are the same as the conventional manufacturing apparatus.

Then, the flat resin tape 10 wound in a coil shape is rewound from the uncoiler 51 and inserted into the thin portion forming device 52 by using the manufacturing apparatus 5. In the thin portion forming device 52, two portions of the flat resin tape 10 are heated by the heating device 521 and then crushed by the crushing device 5.
25, the heating portion of the flat resin tape 10 is pressed from both sides. Thus, a thin portion forming step of crushing both surfaces of the flat resin tape 10 to form the thin portion 15 is performed.

Next, the flat resin tape 10 provided with the thin portion 15 is sent into the insert nozzle 533 of the extruder 53. As described above, the insert nozzle 533 has a passage 534 provided so as to gradually change from a flat plate shape to a desired U-shape. Therefore, the flat resin tape 10 is bent through the passage 534 with the thin portion 15 as a bending point. The flat resin tape 10 gradually changes from the flat plate shape to a desired U-shape, and the core material 11 having a substantially U-shaped cross section is formed.
Becomes

Next, the core material 11 sent out from the insert nozzle 533 joins with the rubber material 190 for the main body in front of the base 535 and is coated thereon. Then, the core material 11 and the rubber material 190 are integrally formed in the base 535 to form the gasket 1 having a desired shape. Thereafter, the gasket 1 is cut into a desired length by a cutting machine 57 through a rubber vulcanizing process in a vulcanizing bath 54 and a cooling process in a cooling bath 55. The progress of these series of steps is advanced by the tension generated by the take-off machine 56.

As described above, in the present embodiment, the flat resin tape 10 is used as the material of the core material 11. Then, the thin-walled portion 15 is provided in advance in a portion of the flat resin tape 10 where bending is performed. Since the thin portion 15 has a locally reduced thickness, it has a lower bending rigidity than its surroundings.

Therefore, the flat resin tape 10 can be very easily bent using the thin portion 15 as a bending point. In addition, by accurately setting the formation position of the thin portion 15, the bending position can be stabilized. Therefore, in the core material forming step, the core material can be easily and accurately formed into a U-shaped cross section.

In this embodiment, the core material forming step is performed using the insert nozzle 533. Therefore, the core material 11 can be easily formed simply by modifying the passage of the conventional insert nozzle 533 without separately providing a special device for performing the core material forming step. This can also reduce equipment costs.

The gasket 1 of this embodiment has a synthetic resin core 11 formed by molding a flat resin tape 10. Therefore, the gasket 1 can be lighter in weight than a conventional gasket using metal as a core material. In addition, the gasket 1 can be easily cut at an arbitrary position because the core material 11 is a synthetic resin. Furthermore, the difference in the coefficient of thermal expansion between the core 11 and the main body 19 can be significantly reduced as compared with the related art. Therefore, the gasket 1 is very easy to handle.

Second Embodiment As shown in FIGS. 10 to 12, this embodiment is an example in which the position of the thin portion 15 formed by the thin portion forming device 52 in the first embodiment is changed. That is, as shown in FIGS. 10 and 11, the hot jet device 52 in the heating device 521 is used.
3 and crushing roller 5 of crushing device 525
The arrangement of 26 is left-right asymmetric. Thereby, as shown in FIG. 12, the shape of the obtained core material 11 was also left-right asymmetric. Then, by changing the extrusion shape in the subsequent extrusion process, a gasket that is asymmetrical left and right can be easily obtained.

Third Embodiment As shown in FIGS. 13 to 15, this embodiment is an example in which the formation of the thin portion 15 by the thin portion forming device 52 in the first embodiment is changed to three places. That is, as shown in FIGS. 13 and 14, the hot jet device 523 in the heating device 521 and the crushing roller 52 of the crushing device 525 are used.
6 were provided in three sets. And flat resin tape 1
The thin portions 15 were provided at three places in the width direction of 0. This gives
As shown in FIG. 15, a U-shaped core 11 close to a V was obtained. Then, by changing the extruded shape in the subsequent extruding step, a gasket having a U-shaped core material 11 whose cross-sectional shape is close to a V-shaped can be easily obtained.

Fourth Embodiment As shown in FIG. 16, this embodiment is an example in which the shape of the core material 11 in the first embodiment is made asymmetrical by changing the left and right bending angles. That is, in the present embodiment, the shape of the passage of the insert nozzle 533 is such that there is a difference in the bending angle between the left and right. As a result, the obtained core material 11 has an asymmetrical bending angle as shown in FIG. Then, by changing the extruded shape in the subsequent extruding step, a gasket having the core material 11 in which the bending angle of the cross-sectional shape is left-right asymmetric can be easily obtained.

Embodiment 5 As shown in FIG. 17, a gasket 2 of this embodiment is for a house and is made of a synthetic resin core material 21 having a substantially U-shaped cross section.
And a rubber body 29 covering the core 21, and the rigidity of the core 21 is partially improved.
The core 21 is made of a thermoplastic resin and has a substantially U-shaped cross-section, and a reinforcing portion 26 for improving the rigidity of the core is made of a thermoplastic resin and is provided with a reinforcing tape 26. It is stuck.

The manufacture of this gasket 2 was performed as follows. That is, a flat resin tape 20 having a flat cross section made of a thermoplastic resin was used as the material of the core 21. And a tape reinforcing step of attaching a reinforcing tape 26 made of thermoplastic resin and having a width smaller than that of the flat resin tape 20 to a reinforcing portion of the flat resin tape 20 corresponding to a portion for improving the rigidity of the core material 11. Was done. Thereafter, a core material forming step of bending the flat resin tape 20 to form a core material 21 having a substantially U-shaped cross section,
An extruding step was performed in which the core material 21 and the main body 29 were integrally formed by coating a rubber material 290 for the main body around the periphery of the body 1.

In executing this manufacturing method, a manufacturing apparatus 6 as shown in FIG. 18 was used. The manufacturing device 6
As shown in the drawing, in the manufacturing apparatus 5 in the first embodiment, a second uncoiler 61 for supplying the reinforcing tape 26 and a tape reinforcing apparatus 62 for performing the tape reinforcing step are added to form a thin portion. A core material forming machine 63 is provided instead of the device 52, and an insert nozzle 533 in the extruder 53 is changed to a conventional shape.

Two second uncoilers 61 are disposed on the left and right below the path of the flat resin tape 20. From each of the second uncoilers 61, a reinforcing tape 26 having a width smaller than that of the flat resin tape 20 is supplied.

As shown in FIG. 19, the tape reinforcing device 62 includes a heating device 62 for heating the reinforcing tape 26.
1 and a pressing device 625 that presses the reinforcing tape 26 and the flat resin tape 20 in an overlapping manner. The heating device 621 includes two left and right hot jet devices 623, each of which is disposed with the nozzle 622 facing the reinforcing tape 26. The nozzle 622 is provided in a flat shape so that the entire width of the reinforcing tape 26 can be heated.

The pressing device 625 has a pair of upper and lower pressure rollers 626. This pressure roller 626
Have a cylindrical shape, and are disposed on both the upper surface side and the lower surface side of the flat resin tape 20. Then, the pressure roller 62
Numeral 6 is provided so as to press the reinforcing tape 26 heated by the heating device 621 in a state where the reinforcing tape 26 is superimposed on the lower surface of the flat resin tape 20.

The core forming machine 63 has a heating device 631 and a forming device 635 as shown in FIG.
As shown in FIGS. 20 and 21, the heating device 631 heats the bent position of the reinforced flat resin tape 20. In the present example, the nozzle 632 is constituted by two hot jet devices 633 provided to be respectively directed to two left and right bending positions.

As shown in FIGS. 20 and 22, the molding device 6
35 has a pair of upper and lower forming rollers 636, 637. The upper forming roller 636 is a male forming roller having a protrusion at the center, and the lower forming roller 637 is a female forming roller having a recess at the center. By holding the flat resin tape 20 between these forming rollers 636 and 637, a desired U-shape can be formed.

In the extruder 53, the insert nozzle 533 in the head 532 has been returned to the conventional structure.
That is, the internal passage 534 of the insert nozzle 533 is kept in a U-shaped cross section from the beginning to the end (not shown).
Other vulcanizing tanks 54, cooling tanks 55, take-off machines 56, and cutting machines 57 are the same as those of the conventional manufacturing apparatus.

Next, the gasket 2 is
In the manufacture of the resin, first, the flat resin tape 20 wound in a coil shape is rewound from the uncoiler 51 and inserted into the tape reinforcing device 62. At the same time, two reinforcing tapes 26 are inserted into the tape reinforcing device 62 from the two second uncoilers 61.

In the tape reinforcing device 62, as shown in FIGS. 23 (a) and 23 (b), the reinforcing tape 26 is heated and softened by the heating device 621 and then superposed on the flat resin tape 20. The application is performed by pressing with the pressure roller 625. As a result, the flat resin tape 20 is in a state in which a reinforcing portion corresponding to a portion for improving the rigidity of the core material 21 is reinforced by the reinforcing tape 26.

Next, the reinforced flat resin tape 20 is
It is sent to the core forming machine 63. Here, the above-mentioned heating device 631 heats and softens the two portions that become the bent portions of the bending process. Next, as shown in FIG.
The flat resin tape 20 is formed by the above-mentioned forming rollers
The core material 21 has a substantially U-shaped cross section.

Next, the core material 21 is inserted into the insert nozzle 533 of the extruder 53. Then, similarly to the first embodiment, an extrusion step of covering the core material 21 with the rubber material 290 for the main body and integrally molding the core material 21 and the main body 29 is performed. As a result, a gasket 2 as shown in FIG. 17 is obtained.
After the rubber is vulcanized in step 4 and cooled in the cooling tank 55, the rubber is cut to a desired length by a cutting machine 57. The progress of these series of steps is advanced by the tension generated by the take-off machine 56.

As described above, in this example, the core material 2
A flat resin tape 20 is used as a raw material, and the tape reinforcing step is performed on the flat resin tape 20. Thus, the core material 21 obtained by bending the flat resin tape 20 has a portion reinforced by the reinforcing tape 26.
Therefore, the obtained gasket 2 has a desired portion reinforced by the reinforcing tape 26.

Further, the core 21 is made of a synthetic resin including the reinforcing portion. Therefore, even after the gasket 2 is reinforced, it is possible to obtain the effects of light weight, easy cutting, small difference in thermal expansion with the main body, and easy handling.

Note that, after the tape reinforcing step in this example, a thin part forming step similar to that of the first embodiment can be performed. That is, the bending process can be performed after the thin portion is provided at the bending point of the bending process of the core material 21. Heating immediately before bending can be omitted. In this case, even when the core material 21 is locally reinforced, bending into a substantially U-shaped cross section can be performed very easily as in the first embodiment.

Embodiment 6 As shown in FIG. 24, this embodiment is a modification of the fifth embodiment.
This is an example in which the reinforcing portion is changed by changing the position where the reinforcing tape 26 is attached. That is, in the example shown in FIG. 24A, the reinforcing tape 2 is provided inside the left and right bent pieces, respectively.
This is an example in which No. 6 is pasted. The example shown in FIG.
This is an example in which four reinforcing tapes 26 are used, and these are affixed to the inside and outside of the bending point of the flat resin tape 20 at the bending point. The example shown in FIG. 3C is an example in which the reinforcing tape 26 is attached only to the outer surface of the portion that becomes the bending point. The example shown in FIG. 3D is an example in which a reinforcing tape 26 is attached to the inner surface of the center of the core 21.

Each of these examples shows different effects in the degree of reinforcement. Further, the position at which the reinforcing tape 26 is attached can be changed to various positions other than the above three examples. Otherwise, the same operation and effect as those of the fifth embodiment can be obtained.

Embodiment 7 In this embodiment, a hole making step is performed in place of the thin portion forming step in Embodiment 1. More specifically, as shown in FIG. 25, prior to the core material forming step, a drilling step of continuously providing a plurality of through holes 3 at predetermined intervals along the longitudinal direction of the flat resin tape 10 was performed. Therefore, the decoiler 51 of the manufacturing apparatus 5 and the extruder 5
3, a drilling device (not shown) was installed in place of the thin-walled portion forming device 52.

The punching device has a die and a punch in which a large number of through holes 3 are continuously provided.
And a roller for applying a bend as a bending point on the line connecting. Then, in this drilling device, as shown in FIGS. 25 and 26, the upper end 101 and the lower end 102 are bent in opposite directions. Others are the same as the first embodiment.

FIG. 26 shows a sectional structure of the obtained gasket 2.
Shown in Also in the gasket 2 of this embodiment, the effect of using the flat resin tape 10 as the core material can be sufficiently obtained as in the above-described embodiments. Further, in this example, by providing a plurality of through holes 3 in the above-described drilling step, it is possible to perform bending with a line connecting these as a bending point as described above. Therefore, in the core material forming step, the bending can be easily performed, and the bending position can be accurately set.

Further, by providing the through-holes 3, the subsequent extrusion process allows the synthetic resin material of the main body 19 to be disposed in a state where the synthetic resin material is passed through the through-holes 3. The connection between the material 11 and the main body 19 can be strengthened.

[0094]

As described above, according to the present invention, it is possible to provide a lightweight gasket using a bent synthetic resin as a core material and a manufacturing method capable of easily manufacturing the gasket.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a gasket according to a first embodiment.

FIG. 2 is an explanatory view showing a core material forming step in the first embodiment.

FIG. 3 is an explanatory diagram illustrating a configuration of a gasket manufacturing apparatus according to the first embodiment.

FIG. 4 is an explanatory diagram illustrating a configuration of a thin-walled portion forming apparatus according to the first embodiment.

FIG. 5 is a front view of a heating device in the thin portion forming apparatus according to the first embodiment.

FIG. 6 is a front view of a crushing device in the thin portion forming device according to the first embodiment.

FIG. 7 is an explanatory view showing a structure of a head portion of the extruder in the first embodiment.

FIG. 8 is an explanatory view showing an insert nozzle according to the first embodiment.

FIG. 9 shows (a) A- in the insert nozzle of FIG. 8;
A line, (b) BB line, (c) CC line, (d) DD
Explanatory drawing which shows the internal passage shape of the position of a line.

FIG. 10 is a front view of a heating device in a thin portion forming apparatus according to a second embodiment.

FIG. 11 is a front view of a crushing device in a thin portion forming device according to a second embodiment.

FIG. 12 is an explanatory diagram showing a core material forming process in the second embodiment.

FIG. 13 is a front view of a heating device in the thin portion forming apparatus according to the second embodiment.

FIG. 14 is a front view of a crushing device in a thin-walled portion forming device according to a third embodiment.

FIG. 15 is an explanatory view showing a core material forming process in the third embodiment.

FIG. 16 is an explanatory view showing a forming process of a core material in a fourth embodiment.

FIG. 17 is a sectional view of a gasket according to the fifth embodiment.

FIG. 18 is an explanatory diagram showing a configuration of a gasket manufacturing apparatus according to a fifth embodiment.

FIG. 19 is an explanatory diagram showing a configuration of a tape reinforcing device according to a fifth embodiment.

FIG. 20 is an explanatory view showing a configuration of a core material forming machine in a fifth embodiment.

FIG. 21 is a front view of a heating device in a core material forming machine according to a fifth embodiment.

FIG. 22 is an explanatory view showing a cross-sectional shape of a forming roller in a core material forming machine in a fifth embodiment.

FIG. 23 is an explanatory view showing a core material forming process in the fifth embodiment.

FIG. 24 is an explanatory diagram showing another four examples of gaskets in the sixth embodiment.

FIG. 25 is an explanatory view showing a forming process of a core material according to the seventh embodiment.

FIG. 26 is a sectional view of a gasket according to the seventh embodiment.

FIG. 27 is a cross-sectional view of a gasket in a conventional example.

FIG. 28 is an explanatory view showing a usage state of a gasket in a conventional example.

FIG. 29 is a cross-sectional view of two reinforced gaskets in a conventional example.

[Explanation of symbols]

 1,2. . . Gasket, 10, 20. . . Flat resin tape, 11, 21. . . Core material, 12. . . Inflection point, 15. . . Thin part, 19, 29. . . Main body, 26. . . 2. reinforcing tape, . . Through holes, 5,6. . . manufacturing device,

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) B29L 31:10 (72) Inventor Akihiro Mitsuru 4-1-1 Naganecho, Obu City, Aichi Prefecture Tokai Kogyo Co., Ltd. F term (reference) 3J040 EA15 EA17 EA43 EA48 FA06 HA01 HA02 4F207 AA04 AA11 AA13 AA15 AD05 AD08 AG03 AG26 AG28 AH13 AH23 AH46 KA01 KA17 KA20 KB18 KJ05 4F209 AA04 AA11 AA13 AA15 NH05 A08 AG03 A03 AG03

Claims (14)

[Claims] 1. A method of manufacturing a gasket comprising a synthetic resin core material and a synthetic resin body covering the core material, wherein a flat resin tape having a flat cross section is used as the material of the core material. A core material forming step of forming a core material by applying a bending process to the flat-plate resin tape, and covering at least a part of the periphery of the formed core material with the synthetic resin material for the body. A method of manufacturing a gasket, comprising performing an extrusion step of integrally molding the core material and the main body. 2. The flat resin tape according to claim 1, wherein a thin portion having a locally small thickness is provided in advance on the flat resin tape, and in the core material forming step, the thin portion is set as a bending point of a bending process. A method for producing a gasket, characterized in that: 3. The core material forming step according to claim 1, wherein, prior to the core material forming step, a thin part forming step of locally forming a thin part in the flat resin tape is performed. In the method, a gasket manufacturing method is characterized in that a bending process is performed on the flat resin tape with the thin portion as a bending point. 4. The flat resin tape according to claim 3, wherein a thermoplastic resin is used as the flat resin tape, and in the thin portion forming step, at least a part of the flat resin tape is heated, and then a pair of crushing rollers is used. A method of manufacturing a gasket, comprising: pressing a heating portion of the flat resin tape from both sides using the method and crushing at least one surface of the flat resin tape to form the thin portion. 5. The method according to claim 1, wherein:
The extrusion step includes a molding die and an insert nozzle disposed upstream of the die. The core material is inserted from inside the insert nozzle, and the synthetic resin material is inserted into the die from around the insert nozzle. The core material forming step is performed by gradually changing from a flat plate shape to a desired shape inside the insert nozzle. A method for producing a gasket, characterized in that the method is carried out by passing the flat resin tape through a passage provided in the gasket. 6. A method for producing a gasket comprising a synthetic resin core material and a synthetic resin body covering the core material, wherein the rigidity of the core material is partially improved. A flat resin tape provided with a reinforcing portion in advance at a position corresponding to a portion for improving the rigidity of the core material is used as a material of the core material, and the flat resin tape is bent to form the core material. A core material forming step and an extrusion step of covering at least a part of the periphery of the formed core material with the synthetic resin material for the main body and integrally forming the core material and the main body are performed. A method for producing a gasket, comprising: 7. A method of manufacturing a gasket comprising a synthetic resin core material, a synthetic resin body covering the core material, and partially improving the rigidity of the core material. A tape reinforcing step of attaching a reinforcing tape to a reinforcing portion of the flat resin tape corresponding to a portion for improving the rigidity of the core material by using a flat resin tape having a flat cross section as a material of the core material; A core material forming step of bending the flat resin tape to form the core material, and coating the synthetic resin material for the main body on at least a part of the periphery of the formed core material; A method for manufacturing a gasket, comprising: performing an extrusion step of integrally molding the gasket and the main body. 8. The flat resin tape according to claim 6, wherein a thin portion having a locally small thickness is provided in advance on the flat resin tape, and in the core material forming step, the thin portion is formed at a bending point of a bending process. A method of manufacturing a gasket. 9. The method according to claim 7, wherein a thermoplastic resin is used for the flat resin tape and the reinforcing tape, and in the tape reinforcing step, at least one of the flat resin tape or the reinforcing tape is heated. A method for manufacturing a gasket, comprising: after softening, bonding by overlapping and pressing. 10. The thin-walled portion forming device according to claim 6, wherein a thin-walled portion locally having a small thickness is formed on the flat resin tape before the core material forming step. A method of manufacturing a gasket, comprising: performing a core material forming step by performing a bending process on the flat resin tape with the thin portion as a center. 11. A gasket comprising a synthetic resin core material and a synthetic resin body covering the core material, wherein the core material is provided by bending a flat resin tape having a flat cross section. A gasket characterized in that a thin portion having a locally small thickness is formed at a bending point of the bending process. 12. A gasket comprising a synthetic resin core and a synthetic resin body covering the core, wherein the rigidity of the core is partially improved. A gasket characterized in that a reinforcing tape is attached to the reinforcing part to improve the rigidity of the gasket. 13. The method according to claim 1, wherein before the core material forming step, a plurality of through-holes are continuously formed at predetermined intervals along a longitudinal direction of the flat resin tape. A method for producing a gasket, comprising: performing a hole forming step of forming a hole; and, in the core material forming step, performing the bending with a bending point on a line connecting the through holes. 14. A gasket comprising a synthetic resin core and a synthetic resin body covering the core, wherein the core is provided by bending a flat resin tape having a flat cross section. A gasket, characterized in that a plurality of through holes are continuously provided at predetermined bending points at bending points of the bending process.