JP3475269B2 - Manufacturing method of sealing material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a sealing material for the purpose of molding a large amount of thermoplastic resin sealing material at high speed.

[0002]

2. Description of the Related Art Conventionally, when a sealing material is formed of a thermoplastic resin, an upper mold and a lower mold having a cavity formed in the shape of the sealing material are used, and if an insert material is required, it is melted together with the insert material. The resulting thermoplastic resin material is put into the cavity to form a mold, which is then cooled and taken out from the cavity to obtain a sealing material having a desired shape,
In the molding method that uses the upper and lower molds for such molding, it is easy to form a large amount in a continuous manner by requiring troublesome procedures such as opening and closing the upper and lower molds and heating and cooling. It is a structure that cannot be changed.

For this reason, recently, referring to the drawings, as shown in FIG. 10, a large number of lower molds (1) are formed.
Of the thermoplastic resin (2) are fed into the heated lower mold (1) in a fixed amount, and the supplied thermoplastic resin (2) is supplied to the lower mold (1). And a lower mold (1) and an upper mold (3) opposed to the lower mold (1) are molded, and a continuous manufacturing method in which the mold is cooled from the upper mold (3) and demolded is invented. (Japanese Patent Publication No. 03-050690) In this manufacturing method, the sealing material (S) is continuously manufactured to improve the production efficiency, and the heating device for the lower mold (1) does not repeat operation and stop, so It has the advantage of being economically superior.

[0004]

However, the continuous molding method in which the sealing material (S) is molded through each step while the upper and lower molds (1, 2) are conveyed is as follows. Except for the conventional molding method, there is no big difference, and the drawbacks of the conventional method are the manufacturing of precise upper and lower molds (1 and 2) and heating of the upper and lower molds (1, 2).・ Cooling, and opening and closing of the upper and lower molds (1, 2) and transportation, etc., show various difficulties. That is, the upper and lower molds (1,
In 2), not only the molding cost is high, but also the maintenance and inspection cost is not negligible, and the upper and lower molds (1, 2)
Naturally, the heat storage capacity also became large, and much time and expense were required for heating and cooling. The upper and lower molds (1, 2) are opened and closed by an insert material (not shown).
This is an indispensable process such as the injection of the mold or the removal of the sealing material (S), which is a molded product, and the shortening of the molding time cannot be expected in the process of opening and closing the upper and lower molds. The present invention has been made in view of such drawbacks, and an object of the present invention is to provide a method for producing a sealing material which is excellent in thermal efficiency and can be continuously and molded in a short time.

[0005]

The present invention will be described with reference to the drawings. As shown in FIG. 1, a round plate (4) having a shape having a rising portion (4a) on the outer periphery is punched and formed from a metal plate material. Then, an adhesive is applied thereto, and as shown in FIG. 2, a predetermined amount of the molten thermoplastic resin (2) is filled into the inside of the round plate (4) that has been preheated by high-frequency heating or the like. As shown in FIG. 3, a molding die (5) at a low temperature (normal temperature) is pressed into the inside of the round plate (4) to apply a pressure to form a thermoplastic resin layer (2a) with an appropriate thickness therein, and the thermoplastic resin The resin (2) overflows to the outer peripheral portion of the rising portion (4a) to form a lip (2b). After that, the mold is removed and the middle part of the round plate (4) is punched out in a circular shape as shown in FIG. 4 together with the thermoplastic resin layer (2a) to form a sealing material (S1).

Further, when the round plate (4) having the rising portion (4a) on the outer periphery is formed by punching from the metal plate material, as shown in FIG. 6, an annular uneven portion is formed in the middle part of the round plate (4). (4b) is simultaneously press-formed, a thermoplastic resin layer (2a) is formed on it by the same method as described above, and then the middle part of the circular dish (4) is formed into a circular shape together with the thermoplastic resin layer (2a). It is characterized by punching.

Further, when the round plate (4) is formed by punching, as shown in FIG. 7, the rising portion (4) formed on the outer periphery is formed.
It is characterized in that a radial flange portion (4c) is formed on the peripheral edge of a). Further, when the center portion of the round plate (4) is formed by punching, as shown in FIG. 8, the extending lip (2c) that is formed by overflowing to the outer peripheral portion is simultaneously punched to a desired size.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has been developed by implementing a simple method for producing a sealing material (S1) as described above, in which one metal plate is used as a dish-shaped rising portion (4a). The thermoplastic resin layer (2a) is formed on the shaped round plate (4) by punching so as to be formed. At this time, the shape of the cover to be pressed from above the molding die (5) and its pressing shape. A lip (2b) made of thermoplastic synthetic resin is formed so as to overflow to the outer peripheral portion of the rising portion (4a) by the pressure. In the shape of this lip, the flange portion (4
The extending lip (2c) protruding from c) is punched into a desired shape to form a sealing material (S1). When the sealing material (S1) formed as described above is attached to the bearing (8) as shown in FIG. 5 and the like where the lip (2b) is press-fitted with the lip (2b), it is sufficiently elastically operated. It exhibits high sealing performance and adhesion with excellent adhesion.

[0009]

EXAMPLES The present invention will be described with reference to Examples. An adhesive is applied to a round plate (4) formed as shown in FIG.
This is heated while being sequentially conveyed to one by one, and a fixed amount of the thermoplastic resin (2) is supplied to the heated round plate (4) as shown in FIG. As shown in FIG.
The thermoplastic resin (2) is molded to the outer peripheral portion of (a) so that the lip (2b) protrudes. Further, in forming the extending lip (2c) when the flange portion (4c) is formed on the rising portion (4a), a forming die (5) whose surface is expanded in the radial direction is prepared as shown in FIG. Then, an extending lip (2c) which is pressed by the molding die (5) from above the thermoplastic resin (2) supplied to a fixed amount so that the thermoplastic resin (2) overflows, and which radially projects between the lower transfer member and the receiving tray. To form. Next, the mold (5) is released from the mold, and the middle part of the round plate (4) thus formed is punched into a circular shape having a desired size as shown in FIG. 4 or 8 to form a sealing material (S1). To do.

When this middle portion is formed by punching, the punching is performed while elastically deforming the thermoplastic resin layer (2a) by adjusting the drawing pressure and the holding pressure of the holding plate (7) and the cut punch (6). It is possible to form a lip shape in which the peripheral edge of the cut surface of the thermoplastic resin layer (2a) is slightly projected from the peripheral edge of the cut surface of the round dish (4). In addition,
An extending lip (2) formed in the edge direction of the flange portion (4c).
In the punching molding of c), as shown in FIG. 8, the middle part of the circular plate (4) is punched at the same time by the same method, and the sealing material having the extending lip (2c) protruding in the radial direction ( S1) is formed.

The sealing material (S
When 1) is attached to the bearing (8) or the like as shown in FIG. 5 where the lip (2b) is press-fitted and fitted, the elastic action provides sufficient adhesion and high sealing performance. Indicates the force of attachment. Further, in the sealing material (S1) in which the extending lip (2c) is formed at the edge of the flange portion (4c), the extending lip (2) protruding in the radial direction as shown in FIG.
If c) is mounted so as to wrap around the flange portion (4c), a strong sealing action is caused and the risk of falling off is eliminated, so that a preferable mounting structure is obtained.

The sealing material (S
When 1) is mounted on the bearing (8), as shown in FIGS. 5 and 9, between the rising portion (4a) having a rigid cylindrical shape or the flange portion (4c) and the bearing (here, the outer ring 8a). The elastic lips (2b, 2c) are interposed and compression fitted, so that the mounting portion is completely sealed and fixed.

Further, in forming the round plate (4), a simple plate shape as shown in FIG. 1 is changed to an uneven portion (4b) which is raised or depressed at the center of the round plate (4) as shown in FIG. It is also possible to form a shape to form, and further to form a flange portion (4c) on the periphery of the rising portion (4a) as shown in FIGS. 7 and 8. In such a concavo-convex shape, mounting workability for the bearing (8) is improved. There are many advantages in the mounting space, and the working disadvantage due to this molding is not insignificant.

Next, the thermoplastic resin (2) is selected from polystyrene type, polydiolefin type, chlorine type and engineering plastic type. This thermoplastic resin (2) can be easily made into a fluid state by appropriate heating, does not require a vulcanization step, and is filled in the round dish (4) and the thermoplastic resin layer in the molding die (5). There are no factors of concern in modeling (2a). Further, the thermoplastic resin (2) has strength characteristics similar to or higher than that of the reinforced vulcanized rubber without adding a reinforcing agent, and is suitable for a bearing seal that slides and seals. Has become. Round plate (4)
In the residual heat of the above, in order to enhance the adhesiveness with the thermoplastic resin (2) to be melt-filled, it is applied to soften the adhesive applied and formed on the inner surface thereof, and the thermoplastic resin (2) is introduced. It is made to be compatible with each other and firmly adhere.

[0015]

With the above-described structure, the following excellent effects can be obtained. The present invention can be omitted by replacing the lower mold, which is indispensable for mold molding, with the round plate (4), which makes the moldability extremely efficient, and shows a great advantage in heating efficiency. In this way, it is possible to fill and mold easily and perform punching processing, which enables a molding cycle in an extremely short time, and because remolding is easy and excellent in recyclability, manufacturing energy and manufacturing cost can be suppressed and it is cheap and large quantity. Can be provided to.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first step of the present invention.

FIG. 2 is a cross-sectional view showing a material filling step of the present invention.

FIG. 3 is a cross-sectional view showing a mold forming process of the present invention.

FIG. 4 is a sectional view showing a cutting step of the present invention.

FIG. 5 is a cross-sectional view showing a state in which the present invention is mounted.

FIG. 6 is a sectional view showing another embodiment of the present invention.

FIG. 7 is a sectional view showing another molding example of the present invention.

FIG. 8 is a cross-sectional view showing another cut example of the present invention.

FIG. 9 is a sectional view showing another mounting example of the present invention.

FIG. 10 is a cross-sectional view showing a conventional example not using the present invention.

[Explanation of symbols]

S sealant S1 sealing material 1 Lower mold 2 Thermoplastic resin 2a thermoplastic resin layer 2b lip 2c extended lip 3 Upper mold 4 round plate 4a Rising part 4b uneven part 4c Flange part 5 Mold 6 cut punch 7 Presser plate 8 bearings 8a outer ring

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B29D 31/00 B29C 43/18

Claims (4)

(57) [Claims] 1. A round plate having a rising portion on its outer periphery is punched out of a metal plate material, and an appropriate amount of thermoplastic resin is filled in a molten state into the round plate which has been heated by applying an adhesive, and then the round plate. A molding die is pushed into the inside to form a resin layer with an appropriate thickness, and the thermoplastic resin overflows to the outer periphery of the rising portion to form a lip. A method for producing a sealing material, which comprises punching a middle portion of a plate into a circular shape. 2. The sealing material according to claim 1, wherein when a round plate having a rising portion on the outer periphery is punched from the metal plate material, an annular uneven portion is provided at the same time in the middle part of the round plate. Manufacturing method. 3. The method for manufacturing a sealing material according to claim 1, wherein a flange portion is formed on a peripheral edge of a rising portion formed on the outer periphery when the round plate is punched and formed. 4. When punching and forming the middle part of the round plate,
4. The method for producing a sealing material according to claim 1, wherein a lip formed by overflowing is formed on the outer peripheral portion by punching.