JPH01210661A - Manufacture of diaphragm - Google Patents

Abstract

PURPOSE:To facilitate application operation and improve quality and yield by forming an elastomer layer forming material with a metal mold for transfer molding and setting a fiber reinforcing layer on a cavity surface in a lower die to close the metal mold and pressing the elastomer forming material with a plunger. CONSTITUTION:An elastomer material 37 is prepared in a pot 21 of a forming metal mold 13 maintained at a predetermined temperature. Next, said metal mold 13 is opened so that an elastomer layer forming material 35 accompanies an upper mold 17 to set a fiber reinforcing layer 31 on a cavity surface 27 of a lower mold 19. Then, said metal mold 13 is closed to press said material 35 with a plunger 15 and apply it to said layer 31 for producing a diaphragm forming material and providing a product with hot press. Thus, the application operation is facilitated and quality and yield are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a diaphragm having a structure in which a fiber reinforced layer and one or more elastomer layers are laminated. This diaphragm is suitable as a component used in a waste gas control device of a vehicle, a component used in a fuel supply device, a component of a switch, or the like.

In addition, in this specification, elastomer refers to synthetic rubber and T
Refers to elastic polymer materials such as PE (thermoplastic elastomer).

<Prior Art> Conventionally, the above-mentioned diaphragm has been manufactured as follows.

This manufacturing method includes (I) manufacturing a diaphragm forming material by laminating a fiber reinforced layer and an elastomer layer forming material in a flat plate shape, and (n) hot pressing the diaphragm forming material to form a diaphragm in a predetermined shape. It is broadly divided into the process of obtaining.

In the former step (I), for example, as shown in FIG. This was done by pasting the . Alternatively, using a calendar roll, sheeting and topping were performed.

In the latter step (!), as shown in FIG. 16, a predetermined shape (!
It consists of a process of cutting out a preparation material 9 (in the form of a disc (in Japanese), and a process of setting this preparation material 9 in a hot press mold and vulcanizing it while shaping unevenness etc. to obtain a diaphragm 10. .

The diaphragm 16 thus obtained is composed of the fiber reinforcing layer 3 and the elastomer layer 11, as shown in FIG.

<Problems to be Solved by the Invention> In the above manufacturing method, in order to make the quality of the diaphragm 10 uniform, there is a problem in the work of pasting the elastomer layer forming material 1 and the fiber reinforced layer 3 in step (1). It had become. This is because, depending on how this operation is performed, there is a risk that the elastomer layer forming material 1 may scorch or air bubbles may be mixed into the elastomer layer forming material 1.

Furthermore, due to the recent demand for higher performance of diaphragms, it is desired that the fiber reinforcing layer 3 be made of knit. In this case, if the elastomer layer forming material 1 and the fiber reinforcing layer 3 are attached by the method described above, the threads of the fiber reinforcing layer 3 are likely to become disordered (if the threads are disordered, it is not desirable as a product).

In order to avoid this, it becomes even more difficult to control the sticking roll 5 and the like.

Further, some diaphragms have a thick portion (bead 12) at the peripheral edge in order to ensure sealing performance in terms of product functionality. The diaphragm 10a with beads 12 is formed by forming the elastomer layer forming material 1 thick in advance, and then forming the elastomer layer forming material 1 during press vulcanization.
It is formed by moving the meat from the center to the periphery. Even through such press vulcanization, fiber-reinforced FI3
There is a risk that the threads may become disordered. This makes it difficult to control press vulcanization.

In other words, the conventional manufacturing method requires skill to manufacture the diaphragm 10.

On the other hand, this means that the yield is low. Furthermore, since the diaphragm forming material 7 is formed in a sheet shape, a scrap portion 8 remains after cutting out the preparatory material 9 of a predetermined shape.

This also causes a decrease in yield.

Therefore, in manufacturing the diaphragm, the present inventors
We have been conducting extensive research with the aim of (1) simplifying manufacturing and (2) improving yield. As a result, it was discovered that the fiber reinforcing layer was set in advance as an insert and the elastomer layer forming material was transfer molded. Then, the manufacturing method of the following study example was performed.

Consideration Example (See Figures 9 to 14) First, we will explain the transfer molding die (hereinafter abbreviated as "molding die") 13. This forming die 13 has a plunger 15, an upper die 1f and It comprises a lower mold 19.

Plunger 15 is hydraulically controlled.

The upper die 17 is attached to a frame (not shown) via a floating plate. A bot 21 that is a sliding fit with the plunger 15 is formed on the top surface. This bot 2
1, a plurality of gates 25 are vertically bored through the cavity surface 23 to communicate with the cavity surface 23.

Reference numeral 27 in the figure is the cavity surface of the lower mold 19. Then, this surface 2F is subjected to mold release treatment (flattening the surface 27 and using fluorine resin) so that when the molding die 13 is opened, the elastomer layer forming material 35 adheres to the upper mold 17. processing, etc.). The grooves 28 and 29 (which become annular when the mold is closed) formed between the opposing surfaces of the upper mold 17 and the lower mold 19 are connected to the retaining ring 3 of the fiber reinforced layer 31.
This is for setting 3.

The molding die 13 having such a configuration is kept at a temperature (for example, 80° C.) at which the aerostomer material does not scorch by a pair of hot plates (not shown).

Next, we will start by explaining the manufacturing method for this study example.
As shown in Fig. 9, in the mold open state, the cavity surface 2 of the lower mold 19
A fiber reinforcing layer 31 is set on top of 7. This fiber reinforcing layer 31 is made of knit and has a circular shape. The peripheral edge thereof is supported by a retaining ring 33. This results in
Even when the fiber reinforcing layer 31 is set on the cavity surface 27, wrinkles will not form. Note that the reference numeral 37 in the figure is a rubber material.

Next, as shown in FIG. 10, the mold is closed and the elastomer material 37 is injected into the cavity using the plunger 15.

Thereafter, the mold is opened as shown in FIG. 11, and the diaphragm forming material 39 is released from the mold (FIG. 12).
As shown in Figure 4, this is hot pressed to obtain a diaphragm.

According to studies by the present inventors, if the diaphragm forming material 39 is formed in this manner, the elastomer layer forming material 35 will hardly have any problems with scorch or air bubbles. However, in the fiber-reinforced layer 31, the threads of the portion directly below the gate 25 of the upper mold 17 expand. This is because the elastomer material injected into the cavity pushes and spreads the threads of the fiber-reinforced layer 31. This is thought to be due to the following. Incidentally, this phenomenon of expanding the threads similarly occurred when the fiber reinforcing layer 31 was made of woven fabric.

In this case, it is inevitable that the quality of the product diaphragm will deteriorate.

Means for Solving the Problems> The present invention is a diaphragm manufacturing method aimed at solving the above problems, in which a diaphragm is manufactured by laminating a fiber reinforcing layer and a nidistomer layer forming material in a flat plate shape close to the product shape. The following steps (1) to (3) consist of a step of manufacturing a forming material and a step of hot pressing the diaphragm forming material to obtain a diaphragm of a predetermined shape, and the steps of manufacturing the diaphragm forming material are performed sequentially. It is characterized by including.

■The process of forming an elastomer layer forming material using a pot-type molding mold that is equipped with a plunger, an upper mold, and a lower mold, and the upper mold has multi-point gates.

■The process of opening the mold so that the elastomer layer forming material follows the upper mold, and setting the fiber reinforcement layer on the cavity surface of the lower mold.

■A process of closing the molding die and applying pressure to the elastomer layer forming material with a plunger to adhere the elastomer layer forming material and the fiber reinforced layer (Example) This invention will be described below based on the Examples. This will be explained in more detail. Note that the same members as those explained in the study example are given the same reference numerals, and the explanation thereof will be partially omitted.

The manufacturing method of the embodiment includes (I) a step of manufacturing a diaphragm forming material 49 by laminating the iM fiber reinforced layer 31 and the elastomer layer forming material 35 in a flat plate shape close to the product shape; and (II)
The process is roughly divided into a process of hot-pressing the diaphragm forming material 49 to obtain a diaphragm of a predetermined shape, and the former process (I) is distinctive.

The former step (I) includes: (1) manufacturing the elastomer layer forming material 35 in a predetermined molding die 13; and (2) changing the molding die 13 so that the elastomer layer forming material 35 is attached to the upper mold 17. Step 2 of opening the mold and setting the fiber reinforcing layer 31 on the cavity surface 27 of the lower mold 19; (1) Closing the molding die 13 and pressurizing the elastomer layer forming material 35 with the plunger 15 to form the elastomer layer. It consists of a step of pasting the forming material 35 and the fiber reinforcing layer 31.

(2) A step of manufacturing the elastomer layer forming material 35 using the molding die 13 (FIG. 1.2).

Elastomer material 37 to pot 21 of molding die 13
(FIG. 1), this molding die 13 has a gate 25 with a diameter of 0.5 mm when the thickness of the cavity (the distance between the cavity surface 23 and the cavity surface 27) is 0.5 mm.
The injection pressure by the plunger 15 was set at 98 g/cm'.

Elastomer materials include silicone rubber, fluororubber,
Examples include synthetic rubbers such as nitrile rubber (NBR) and TPEs such as polyolefins. In addition, the molding die 13 is
It goes without saying that the rubber material is kept at a temperature at which it will not scorch, and the TPE material at a temperature at which it will not become fluid.

The elastomer layer forming material obtained in this step (2) can also be of two colors. This elastomer layer forming material 35a is
It is manufactured using a molding die 43 shown in FIG. The reference numeral 45 in the figure is a partition wall, and the reference numeral 47 is an insert ring.

Of course, the elastomer layer forming material can be molded in three or more colors.

■The step of opening the mold 13 so that the elastomer layer forming material 35 is attached to the upper mold 17, and setting the fiber reinforcing layer 31 on the cavity surface 27 of the lower mold 19 (Fig. 3)
.

As mentioned above, the cavity surface 27 of the lower mold 19 has been subjected to mold release treatment, so when the mold is opened, the elastomer layer forming material 35 adheres to the upper mold 17 and is accompanied by the lower mold. It will be separated from 19. Then, while maintaining the mold open state, the fiber reinforcing layer 31 is inserted into the cavity surface 27 of the lower mold 19.
set on top. At this time, since the retaining ring 33 is present, almost no wrinkles occur in the fiber reinforcing layer 31. In addition,
This retaining ring 33 may be omitted. However, it is preferable that the fiber reinforcing layer 31 is wider than the elastomer layer forming material 35. This is because when the molding die 13 is closed, the fiber reinforcing layer 31 is sandwiched between the mating surfaces, and the thickness of the cavity increases by the amount of the fiber reinforcing layer 31.

The material of the reinforcing fibers forming the fiber reinforcing layer 31 is not particularly limited, and examples thereof include polyamide and polyester. Further, the fiber reinforcing layer 31 may be a woven fabric or a woven fabric. It is preferable to apply an adhesive to this fiber reinforcing layer 31 from the viewpoint of improving adhesiveness with the elastomer layer forming material 35.

■While closing the molding die 13, the plunger 1
Step 5 of applying pressure to the elastomer layer forming material 35 to adhere the elastomer layer forming material 35 and the fiber reinforced layer 31 (FIG. 5.6).

The pressing force by the plunger 15 may be 98 g/cm'') as in step (2), and the pressing time is 30 to 60 seconds. Set as appropriate depending on the roughness.

The thus obtained diaphragm forming material 49 was released from the molding die, and the present inventors visually observed the state of the fiber reinforcing layer 31 adhered to the elastomer layer forming material 35.

When the elastomer layer forming material 35 and the fiber reinforcing layer 31 are attached in this manner, the flesh of the elastomer layer forming material 35 is evenly inserted between each thread of the fiber reinforcing layer 31. That is, the threads of the fiber reinforcing layer 31 are hardly disordered.

Note that the elastomer layer forming material 3 is applied to both sides of the fiber reinforcing layer 31.
5, as shown in FIG.
The lower mold 17 in step 1 is converted into one (lower mold 53) having the cavity recess 51, and the steps ① to ③ are repeated again.

Diaphragm 10a with bead 12 shown in FIG.
When forming a bead 12, the cavity shape is adjusted (a recessed portion for forming the bead 12 is provided) and the process is performed in the same manner as described above.

Next, the process of hot pressing the diaphragm forming material 39 to obtain a diaphragm will be explained.

The diaphragm forming material 49 shown in FIG. 6, including the retaining ring 33, is set into a press mold 61 and hot pressed. The hot pressing conditions are: 160°C x 6 minutes, compression force 5t, when the elastomer material 37 is NBR.

As a result, the elastomer layer forming material 35 is vulcanized to become the elastomer layer 11 (see FIG. 17), and is vulcanized and bonded to the fiber reinforcing layer 31. At the same time, the elastomer layer 11 is shaped into a square according to the unevenness of the press surface of the press die 61. And elastomer layer 11
When cutting the peripheral edge of , including the fiber reinforcing layer 11,
A predetermined diaphragm 10 will be obtained.

Of course, the threads of the fiber reinforcing layer 31 are not disturbed in this hot pressing step.

<Effects of the Invention> As explained above, the method for manufacturing a diaphragm according to the present invention includes the steps of manufacturing a diaphragm forming material by laminating a fiber reinforcing layer and an elastomer layer forming material in a flat plate shape close to the product shape; and hot pressing the diaphragm forming material to obtain a diaphragm of a predetermined shape, and the step of manufacturing the diaphragm forming material is characterized in that it includes the following steps (1) to (3) which are performed sequentially.

■The process of forming an elastomer layer forming material using a pot-type molding mold consisting of a plunger, an upper mold, and a lower mold, with multi-point gates formed in the upper mold.

■The process of opening the mold so that the elastomer layer forming material follows the upper mold, and setting the fiber reinforcement layer on the cavity surface of the lower mold.

■The process of closing the mold and applying pressure to the elastomer layer forming material with a plunger to adhere the elastomer layer forming material and the fiber reinforced layer.The diaphragm manufactured by this process is of the beaded type. However, the fiber-reinforced layer is of high quality with almost no disturbance in the threads.And according to the above manufacturing method, the work of pasting the elastomer layer forming material and the fiber-reinforced layer is done using a molding die. Since the process was carried out using the same method, the work was made as easy as simply setting the fiber reinforcing layer as an insert.

Further, according to the manufacturing method of the present invention, the curved portion 8 shown in the conventional example (FIG. 16) is not formed, so there is an effect that the yield can be improved.

[Brief explanation of the drawing]

1 to 6 are cross-sectional views showing the manufacturing step (I) of the diaphragm forming material 49 in the manufacturing method of the embodiment of the present invention, FIG. 1.2 shows the first step, and FIG. 4.5.6 shows step ①. FIG. 7.8 is a sectional view showing a modified form of the transfer molding die. 9 to 12 are cross-sectional views showing the manufacturing process (I) of the diaphragm forming material 39 in the manufacturing method of the examined example, and
3.14 is a cross-sectional view showing the hot press process (■) of the example and the study example. FIG. 15 is a cross-sectional view showing the pasting work of the elastomer layer forming material 1 and the fiber reinforced layer 3 in the conventional example. , FIG. 16 is a plan view showing the preparation material 9, FIG. 17 is a sectional view of the diaphragm 10, and FIG. 18 is a sectional view showing the diaphragm 12a of the type having beads 12. 1.35... Elastomer layer Forming material, 3.31...
Fiber reinforcement layer? , 39.49... diaphragm forming material, 10...
Diaphragm, 11... Elastomer layer, 13... Transfer mold, 15... Plunger, 17... Upper die, 19... Lower die, 23.27... Cavity forming surface, 61 ...Press mold. Patent application Toyoda Gosei Co., Ltd. No. 11! I Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12

Claims (1)

[Scope of Claims] A method for manufacturing a diaphragm having a laminated structure of a fiber reinforced layer and one or more elastomer layers, the method comprising forming the fiber reinforced layer and the elastomer layer forming material into a flat plate shape close to the product shape. and a step of hot pressing the diaphragm forming material to obtain a diaphragm with a predetermined shape. 1
) to (3), (1) for pot-type transfer molding, comprising a plunger, an upper die, and a lower die, the upper die having a multi-point gate; (2) opening the transfer molding mold so that the elastomer layer forming material follows the upper mold; setting the fiber reinforcing layer on the cavity surface of the mold; (3) closing the transfer mold and pressurizing the elastomer layer forming material with the plunger to separate the elastomer layer forming material and the fibers; The process of pasting the reinforcing layer.