JPH0460804B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a tire curing mold.

(Prior art) As a mold for vulcanization of automobile tires, JP-A-57
Those described in JP-A-182415 and JP-A-60-171113 are known. As shown in FIGS. 3 and 4, these vulcanization molds include an upper mold 1 and a lower mold 2 for molding the carcass portion of the tire, and the above-mentioned mold for molding the tread portion of the tire. It consists of a plurality of circumferential segments 3 arranged in a ring shape between an upper mold 1 and a lower mold 2,
This circumferential segment 3 is vertically slidably attached to the inner surface of a taper rig 1a extending downward and extending along the outer periphery of the upper mold, and the upper mold 1 is opened from above in order to close the upper mold 1 in an open state. When descending, the hook 4 protruding from the lower surface of the circumferential segment 3 is inserted into the slot 2a provided in the receiving seat at the periphery of the lower mold 2, and as the upper mold 1 descends, the hook 4 is inserted into the lower mold. When the upper mold 1 is moved toward the center of the mold 2 and the upper mold 1 is closed, the tip of the hook 4 is hooked onto a claw 2b at the end of the slot 2a. In the mold disclosed in Japanese Patent Application Laid-Open No. 57-182415, the circumferential segment 3 comes into contact with the inclined cam 5 (see FIG. 4) standing between the slots 2a and 2a when descending, thereby lowering the circumferential segment 3. In a mold that does not have the above-mentioned inclined cam, the circumferential segment 3 comes into contact with the receiving seat on the periphery of the lower mold 2 and then slides horizontally toward the center. There is.

(Problem to be Solved by the Invention) Conventionally, in order to facilitate the formation of the slot 2a on the periphery of the lower mold 2, the outer side from the slot 2a is lowered in the periphery during molding of the lower mold 2. Form a step like this,
The lower surface of the claws 2b protruding at predetermined angular intervals is finished by lathe processing, and a ring shape separate from the lower mold 2 is formed in advance on the peripheral step of the lower mold 2, and its inner surface The receiving seat 6, which is provided with a recess corresponding to the slot 2a, was fixed by welding, but the contact surface between the lower die 2 and the receiving seat 6 is wide, and it is impossible to weld the entire surface. Since the welding points will be partial, this mold will be used to vulcanize and mold an automobile tire, and the lower mold 2 will be repeatedly heated, cooled, and pressurized, which will cause cracks to occur at the welded points. Therefore, there was a problem that the precision of the mold deteriorated and the quality of the product tire deteriorated.

The present invention provides a tire vulcanization mold that does not generate the above-mentioned cracks and does not cause deterioration in mold accuracy.

(Means for solving the problem) A receiving seat for supporting the circumferential segment and the lower surface of the tapered ring is integrally molded around the lower mold, and the receiving seat supports the lower surface of the tapered ring. A slot for allowing the radial movement of the hook protruding from the hook is bored vertically through the slot, and a claw on which the tip of the hook hangs is fixed to the radially inner end of the slot.

(Function) When the upper die in the upper position is lowered, the circumferential segment descends together with the upper die, the hook at the lower end of the circumferential segment enters the slot around the lower die, and the circumferential segment moves into the lower die. As the hook moves toward the center, the hook moves within the slot, and as the upper mold closes, the hook is housed within the slot.

(Example) A tire curing mold was formed using the upper mold 1 shown in FIG. 3, the circumferential segment 3, and the lower mold 10 shown in FIGS. 1 and 2. In the lower mold 10 shown in FIGS. 1 and 2, 10a is a carcass molding part;
0b is a peripheral receiving seat, and the lower mold 10, including the receiving seat 10b, is integrally molded by casting steel. However, the receiving seat 10b has a plurality of slot holes 1 corresponding to the circumferential segments 3.
0c are formed through the upper and lower portions at regular angular intervals during the above-mentioned casting process. A step 10d is recessed in the upper edge of the slot 10c on the center side of the lower mold, and a claw 11 for hooking the hook 4 is fixed to this step by welding. Incidentally, a slope cam 12 described in the above-mentioned Japanese Patent Application Laid-Open No. 182415/1983 is fixed in an upwardly protruding manner between the adjacent slots 10c.

In the above structure, when a green tire is attached to the lower die 10 and the upper die 1 is lowered, the green tire is compressed after the upper die 1 engages with the upper beat portion of the green tire. On the other hand, the circumferential segment 3 is suspended from the upper die 1 and descends, but after the inclined groove cut on the outer periphery of the circumferential segment 3 fits into the inclined cam 12, The circumferential segment 3 is guided to descend radially inward in an inclined manner, and the tapered ring 1a
At the same time as contacting the receiving seat 10b of the lower die 10, the circumferential segment 3 reaches the innermost end of its stroke and stops. Then, the hook 4 fixed to the circumferential segment 3 enters the slot 10c as the circumferential segment 3 descends, moves further inward in the radial direction, and engages under the claw 11.

In the above embodiment, the inclined cam 12 is omitted, and the lower surface of the circumferential segment 3 comes into contact with the receiving seat 6 of the lower mold 2 as the upper mold 1 descends, and then slides horizontally inward in the radial direction. Good too. However, when the circumferential segment 3 is lowered radially inward in an inclined manner as in the embodiment, the inner protrusion of the circumferential segment that contacts the tread surface of the green tire has a speed that is approximately the same as the compression speed of the green tire. Since the green tire digs in while descending, the uniformity of the product tire improves. Further, although the above embodiment is an example in which cast steel is used for casting, the lower mold 10 described above can be manufactured by cutting a steel plate. In this case, the groove hole 10c is cut by cutting and machining. formed by

(Effects of the Invention) In this invention, the lower mold is integrally formed with the receiving seat around it, and a slot for receiving the hook at the lower end of the circumferential segment is bored through the receiving seat. , there are no welded parts on the receiving seat, making it easy to manufacture, reducing the number of days required for manufacturing, making it cheaper to manufacture, and improving durability.
Cracks that previously occurred at welded areas are eliminated, improving the quality of manufactured tires. Since the claw is manufactured separately from the lower mold and the receiving seat and is fixed around the groove in the receiving seat, a recess into which the tip of the hook can fit can be formed on the underside of the claw, and the claw and the receiving seat can be made in a recessed area. The contact part of the seat is located on the top surface of the catch seat, and the contact area is small, so the entire contact part can be easily welded. Therefore, it has a strength comparable to or higher than that of a one-piece molding, and is superior to that of a conventional catch seat. It does not crack like a welded part.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of the main part of an embodiment of the present invention.
FIG. 2 is a plan view of the lower die shown in FIG. 1, FIG. 3 is a vertical sectional view of a conventional mold, and FIG. 4 is a plan view of the conventional lower die. 1: Upper mold, 3: Circumferential segment, 4: Hook, 10: Lower mold, 10a: Carcass molding part, 10
b: Receiving seat, 10c: Slot, 10d: Step, 1
1: Nails.

Claims (1)

[Claims] 1 An upper mold and a lower mold arranged above and below to mold the carcass part of the tire, and a plurality of rings arranged between the upper mold and the lower mold to mold the tread part of the tire. This circumferential segment is vertically slidably attached to the inner surface of a tapered ring that protrudes downward along the outer periphery of the upper mold. In a tire curing mold in which the circumferential segments move from the outside of the lower mold toward the center, a receiving seat is provided around the lower mold to support the circumferential segments and the lower surface of the taper ring. The receiving seat is formed integrally with the mold, and a slot is bored vertically through the receiving seat to allow the radial movement of the hook protruding from the lower surface of the tapered ring. A tire vulcanizing mold characterized by a fixed hook at the tip of the hook.