JP2922786B2 - Vulcanization molding equipment for rubber products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vulcanizing and molding apparatus for rubber products, in which air is evacuated from a cavity when a mold comprising an upper mold and a lower mold is closed.

[0002]

2. Description of the Related Art A vulcanization molding apparatus for rubber products which is designed to release air from a cavity when a mold is closed is disclosed in Japanese Patent Publication No. 57-44458. In this device, an upper mold is provided with an upper mold and a cylindrical upper enclosing frame surrounding the upper mold, and a lower mold and a cylindrical lower enclosing frame surrounding the lower mold are arranged on the lower substrate. A heat-resistant seal packing is protruded inward from the open end of the upper enclosing frame so that it can be slidably pressed against the outer surface of the lower enclosing frame. Before depressurizing, the inside of the upper and lower surrounding frames is decompressed.

[0003]

However, in the above device, the outer surface of the lower enclosing frame is fitted airtightly and slidably on the inner surface of the heat-resistant seal packing provided at the open end of the upper enclosing frame. Therefore, it is necessary to precisely align the upper and lower enclosing frames in addition to the upper die and the lower die. Therefore, when the size of the mold is increased to a diameter or a side length of 1500 mm or more, it is extremely difficult to align the molds, and the pressure in the cavity is incompletely reduced. As a result, a recess may be formed on the surface of the product.

According to the present invention, an upper mold and a lower mold are surrounded by a frame,
In the one in which the air in the frame is evacuated before the upper mold and the lower mold are approached, it is easy to align the center of the frame to keep the inside of the frame airtight. For example, the side length is 2000 mm like a diaphragm of a filter press. An object of the present invention is to provide an apparatus for molding and vulcanizing a rubber product which can be used for the molding and vulcanization of a large-sized rubber product exceeding the above.

[0005]

According to the present invention, an upper die is provided with an upper die and a cylindrical upper enclosing frame surrounding the upper die, and a lower die is provided with a lower die and a lower enclosing frame surrounding the lower die. The upper and lower dies are moved up and down with respect to one of the upper and lower bases to open and close the upper and lower dies and the upper and lower enclosing frames, respectively.The upper and lower dies are closed before the upper and lower dies are closed. in vulcanization molding apparatus of a rubber product so as to discharge air from the interior space of the upper dam and lower dam closed, made of a rubber-like elastic body under end face of the upper dam, compressible vertically heat a seal packing is fixed to the hanging shape, a vulcanization molding apparatus rubber products forming the seat of the heat seal packing to the end surface on the lower dam.

The above-mentioned heat-resistant seal packing seals against a receiving seat before the upper mold and the lower mold are closed, and is compressed while maintaining the seal until the upper mold and the lower mold are closed.
Ri, a C-shaped convex cross section outwardly, downwardly in a curved portion of the convex bottom, and the thickness is formed so as gradually smaller toward the bottom from the top, which is the upper surrounding frame It is fixed to the lower end surface in a hanging manner . Then, the receiving seat formed on the upper end face of the lower dam, stopper is set <br/> Ke to limit the sliding of the lower end portion of the heat seal packing along its inner edge.

[0007]

The upper mold and the lower mold are opened up and down, a molding material made of unvulcanized rubber-like elastic material is placed on the lower mold, and then the upper base is lowered or the lower base is raised. Before the mold and the lower mold approach, the free end of the heat-resistant seal packing starts to contact the receiving seat before closing, and the inner space of the upper and lower enclosures including the upper mold and the lower mold is sealed. Next, the space between the upper mold and the lower mold is reduced, and air is removed from the inner space while the heat-resistant seal packing is compressed in the vertical direction, and after the inner space is almost evacuated, the upper mold and the lower mold are closed. Can be Therefore, by heating the upper mold and the lower mold, vulcanization molding is performed in a state where the molding material is in close contact with the cavity surfaces of the upper mold and the lower mold. And
After heating for a predetermined time, gradually introduce outside air and raise the upper base or lower the lower base, and the upper and lower molds will be opened, and the heat-resistant seal packing will have its elastic and original shape. Returning, a gap is formed in the contact portion between the heat-resistant seal packing and the receiving seat, and outside air enters the inner space of the upper and lower dies to cool the vulcanized molded product.

By fixing the heat-resistant seal packing to the lower end surface of the upper surrounding frame in a hanging manner, the heat-resistant seal packing is easily returned to the original shape when the upper mold and the lower mold are opened. Also, by molding the heat-resistant seal packing into a shape having a C-shaped cross section outwardly convex, having a downwardly convex curved portion at the lower end, and having a thickness gradually decreasing from the upper end to the lower end, The compression distance in the sealed state can be increased, and the durability is improved. Also, in this case, if a stopper is provided along the inner edge of the receiving seat provided on the lower surrounding frame to limit the sliding of the lower end of the heat-resistant seal packing, the lower end of the heat-resistant seal packing slides on the receiving seat. It is possible to prevent the air from leaking from the inner edge of the receiving seat.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 10 denotes an upper heating plate fixed to a frame (not shown). An upper base 11 is fixed to the lower surface of the upper heating plate 10, and an upper mold (convex mold) 12 for molding a filter press diaphragm is fixed to the lower center of the upper base 11 by an upper mold mounting seat 13. A plurality of guide holes 12a and valve holes 12b are formed along the outer periphery of the upper
A pusher 14 is slidably attached to the valve hole 12b vertically, with each being vertically pierced with appropriate a. The tip (lower end) of the pushing tool 14 projects from the surface of the upper mold 12 when compressed air is supplied from the outside to the valve hole 12b, pushes out the diaphragm Sb (see FIG. 2) of the product, and stops the supply of the compressed air. Then, it is retracted into the valve hole 12b by the action of the compression coil spring to form a part of the surface of the upper die 12.

An upper frame 15 is fixed to the upper base 11 by an upper frame mounting seat 16 so as to surround the upper mold 12.
A heat-resistant seal packing 17 made of heat-resistant rubber is fixed to the lower end surface of the upper surrounding frame 15 in a hanging manner. The heat-resistant seal packing 17 is formed in a C-shaped cross section, has a T-shaped mounting base 17a at the upper end, and has a C-shaped main body portion having an outwardly projecting intermediate curved portion 17b and a downwardly projecting continuous portion. Are formed so that the thickness gradually decreases from the upper end to the lower end,
The mounting base 17 a is embedded in a recess formed in the lower end surface of the upper surrounding frame 15, and is fixed by a presser 18. An air hole 15a is formed in a part (the right end in FIG. 1) of the upper enclosing frame 15 so as to extend horizontally through the upper enclosing frame 15, and a vacuum pump (shown in FIG. Is not connected.

The upper base 11 has an upper surrounding frame 15.
Spring suspension bolts 20 are planted with their heads facing down at the four outer corners surrounding the head.
The compression coil spring 21 is mounted between the compression coil spring 21 and the front surface. The height of the heat-resistant seal packing 17 with respect to the surface of the upper base 11 is formed larger than the height of the upper die 12.

On the other hand, a lower heating plate 30 is provided below the upper base 11.
Are provided so as to be able to move up and down, and are moved up and down by driving a hydraulic cylinder (not shown). A lower substrate 31 is fixed on the lower heating plate 30, and a lower die (concave) 32 corresponding to the upper die 12 is provided on the lower substrate 31 with a lower die mounting seat 33.
Fixed by A plurality of guide pins 34 are implanted along the outer periphery of the lower die 32 in an upright manner corresponding to the guide holes 12a of the upper die 12.

A lower frame 35 having a lower height than the lower die 32 is fixed to the lower base 31 by a lower frame mounting seat 36 so as to surround the lower die 32. A smooth receiving seat 35a with which the lower end of the heat-resistant seal packing 17 contacts is formed, and a stopper 35b is protruded along the inner edge of the receiving seat 35a. A cylindrical spring receiver 3 having holes 37a at the four corners of the lower surrounding frame 35 into which the heads of the spring suspension bolts 20 can be inserted.
7 are integrally formed, and the lower ends thereof are inserted into cutouts provided at the four corners of the lower base 31, and are supported on the lower heating plate 30.

In the above structure, as shown in FIG.
The lower base 31 is lowered to open the upper mold 12 and the lower mold 32 up and down, and a sheet-like material Sa made of unvulcanized heat-resistant rubber is placed on the lower mold 32. Next, when the lower base 31 is raised, first, the lower end curved portion 17 of the heat-resistant seal packing 17 is first raised.
c, the receiving seat 35a of the lower enclosing frame 35 comes into contact, the heat-resistant seal packing 17 is gradually compressed as the lower base 31 rises, and the lower end curved portion 17c slides inward while the mounting base portion thereof is mounted. The vicinity of the lower end of 17a and the intermediate curved portion 17b are mainly bent and flattened. When the lower end of the heat-resistant seal packing 17 comes into contact with the stopper 35b of the receiving seat 35a, the sliding is stopped, and the bending is continued in this stopped state. Further, the guide pins 34 on the lower die 32 are fitted into the guide holes 12a of the upper die 12 with the rise of the lower base 31, thereby preventing the displacement of the upper die 12 and the lower die 32.

After the inner space of the upper and lower surrounding frames 15 and 35 is hermetically sealed by the contact between the heat-resistant seal packing 17 and the receiving seat 35a, when the vacuum pump connected to the air pipe 19 is driven, The air in the inner space is discharged to the outside. Then, after the inner space is almost evacuated, as shown in FIG. 2, the upper mold 12 and the lower mold 32 are closed, and the above-mentioned sheet-like cloth Sa is moved to the product diaphragm Sb.
The molded product is heated by heat transmitted from the upper and lower hot plates 10 and 30 by being left in this closed state for a predetermined period of time, and its vulcanization molding proceeds to obtain a product diaphragm Sb. Can be

Then, outside air is introduced into the upper and lower surrounding frames 15 and 35 through the air pipe 19 and the air hole 15a, and the lower heating plate 30 is lowered.
Begins to open. At this time, the lower hot platen 30 is pushed down by the elasticity of the compression coil spring 21 which has been compressed between the upper base 11 and the spring receiver 37 on the lower base 31 when the lower hot platen 30 rises, so that the lower hot platen 30 can be easily lowered. Become. In addition, by sending compressed air to the valve hole 12b of the upper die 12, the extruding tool 14 in the valve hole 12b protrudes and peels the product diaphragm Sb from the die surface of the upper die 12. Then, as the lower base 31 descends, the heat-resistant seal packing 17 returns to its original shape by elasticity, and its lower end and the lower enclosing frame 3 are removed.
When a gap is formed between the upper mold 12 and the lower mold 32, cool air enters the periphery of the upper mold 12 and the lower mold 32, and the product diaphragm Sb is cooled.

The embodiment shown in FIGS. 3 and 4 facilitates the attachment and detachment of the sheet-like material Sa and the product diaphragm Sb. In FIG. 3 and FIG.
In the same manner as described above, the upper mold 12 and the upper enclosing frame 15 are fixed via the upper base 11, a heat-resistant seal packing 17 is fixed to the lower end surface of the upper enclosing frame 15, and a part of the upper enclosing frame 15 is vented. An air hole 15a is opened. A lower hot platen 30 is provided below the upper base 11 so as to be able to move up and down, and a large number of guide wheels 41 are arranged in two rows on the left and right (on the paper surface in FIG. The front and rear sides of the guide wheels 41 are arranged on the front and rear sides, and the access board 42 is mounted on the front and rear two rows of guide wheels 41. The lower mold 32 and the lower surrounding frame 35 are mounted on the access board 42 via the lower base 31. Similarly fixed.

As shown in FIG. 4, the access board 42 is
The lower hot plate 30 is made to have a size straddling the width direction, and both right and left ends thereof are mounted on the guide wheels 41 described above. A rack 43 is fixed to the left and right sides of the lower surface of the entry / exit board 42, and a pinion 44 meshing with the rack 43 is attached to a lower frame (not shown), and one of the pinions 44 is driven by a motor 45 via a gear train 46. When driven, the forward / reverse rotation causes the entrance / exit board 42 to move back and forth between the upper portion of the lower hot platen 30 at the lowered position and the standby position at the rear thereof.

Therefore, when the access board 42 is at the standby position, the sheet-like material Sa is placed on the lower mold 32 thereon, and then the access board 42 is advanced onto the lower hot platen 30,
Thereafter, when the lower hot platen 30 is raised, the upper and lower surrounding frames 15 and 35 are closed as described above, and then the upper mold 12 and the lower mold 32 are closed to perform vulcanization molding. After the vulcanization molding is completed, the lower hot platen 30 is lowered, and the upper mold 1
2 and the lower mold 32 are opened, the upper and lower surrounding frames 15 and 35 are opened, and after the lower hot platen 30 reaches the lower end of the downward stroke, the input / output platen 42 is retracted to the standby position. It can be easily taken out.

[0020]

According to the first aspect of the present invention, a heat-resistant seal packing which is made of a rubber-like elastic material and is compressible in the vertical direction is fixed to one end face of the upper and lower enclosing frames, and the other end face is fixed to the other end face. Before the upper and lower molds are closed, the space surrounding the upper and lower molds is depressurized and the air in the cavity is suctioned and removed, so that the vulcanization molding becomes a product because the seat for the heat-resistant seal packing is formed. The surface of the product can be finished to a smooth surface without dents due to air bubbles, and the heat-resistant seal packing and the receiving seat are vertically opposed to each other, and the heat-resistant seal packing is compressed in the vertical direction. In comparison with the case where the lower enclosing frame is fitted and the packing is interposed in the fitting portion, the centering is remarkably easy, and it can be used for vulcanization molding of a large product.

Further , the heat-resistant seal packing is fixed to the lower end surface of the upper enclosing frame in a hanging manner, and has a C-shaped cross-sectional shape which is outwardly convex, and has a downwardly convex curved portion at the lower end. , And the thickness is gradually reduced from the upper end to the lower end, and the receiving seat is formed smoothly on the upper end surface of the lower enclosing frame. The packing can be easily returned to its original shape, and the compression distance in the sealed state can be increased.
The durability is improved.

Since a stopper for restricting sliding of the lower end of the heat-resistant seal packing is provided along the inner edge of the seat formed on the upper end surface of the lower enclosing frame , the lower end of the heat-resistant seal packing is provided at the lower end. To disengage from the inner edge of the receiving seat to prevent air leakage.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a mold is opened.

FIG. 2 is a sectional view showing a state in which a mold is closed.

FIG. 3 is a cross-sectional view of another embodiment before a lower mold is carried in.

FIG. 4 is a cross-sectional view after the lower mold of FIG. 4 is carried in.

[Explanation of symbols]

 10: Upper heating plate 11: Upper substrate 12: Upper die 15: Upper enclosure 17: Heat-resistant seal packing 17a: Mounting base 17b: Middle curved portion 17c: Lower curved portion 30: Lower heating plate 31: Lower substrate 32: Lower die 35: Lower surrounding frame 35a: Receiving seat 35b: Stopper 41: Guide wheel 42: Doorway 43: Rack 44: Pinion

Continued on the front page (58) Fields investigated (Int.Cl. ⁶ , DB name) B29C 35/02 B29C 33/02 B29C 33/10 B29C 33/76 B29C 43/36 B29C 39/26 B29C 45/26

Claims (1)

(57) [Claims] 1. An upper base and an upper die and a cylindrical upper enclosing frame surrounding the upper die, and a lower die and a lower enclosing frame surrounding the lower die are provided on one of the upper base and the lower base. The upper and lower dies and the upper and lower enclosing frames are opened and closed respectively, and the upper and lower enclosing frames are closed before the upper and lower dies are closed. in vulcanization molding apparatus rubber products from the inner space of the frame so as to discharge the air, made of a rubber-like elastic body under end face of the upper dam, the compressible heat seal packing fixed to suspended form in the vertical direction , it forms a seat for the heat seal packing to the end surface on the lower enclosure frame, the
C-shaped cross section of heat-resistant seal packing is outwardly convex
Having a downwardly convex curved portion at the lower end, and having a thickness
Is formed so that it gradually decreases from the top to the bottom
And the heat-resistant seal packing along the inner edge of the receiving seat.
A vulcanization molding apparatus for rubber products, characterized in that a stopper for restricting sliding of a lower end of the ring is provided .