JPS6021043B2 - tire molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a tire molding machine, particularly a tire molding machine that inflates a tire molding member in a hollow part of a mold, presses it, and then vulcanizes it to mold a tire. This relates to a tire molding machine that prevents air from entering the vent holes.

In general, tires for ground vehicles have a tread section with deep, large irregularities on the surface to prevent slippage and provide traction to wear-resistant members, and at the same time to improve heat dissipation. It is made up of a carcass part that supports and is configured to withstand bending and stretching, and a bead part that serves to withstand tube pressure, impact, or centrifugal force and fix the tire to the rim. FIG. 1 is a half-sectional view of a mold portion of a conventional tire molding machine, and 1 in the figure is a mold having a ring-shaped recess IA, and a heating plate (not shown) is integrally provided therein.

2 is a vent hole penetrating outward from the recess IA of the mold 1;
Reference numeral 3 indicates a protrusion provided on the inner surface of the recess IA to create the unevenness of the tread portion.

Reference numeral 4 denotes a tire, which is composed of a tread portion 4A having a groove formed by the projections 3 to provide anti-slip and traction force, a carcass portion 4B, and a bead portion 4C.

Reference numeral 5 indicates an airbag formed of a thick heat-resistant tube, and 6 indicates a high-temperature pressurized water area, which indicates an injection port into which a pressurizing material such as compressed air is press-fitted.

To mold a tire, as shown in FIG. 1, the air bag 5 with the tire molding material wrapped around it is inserted into the recess IA of the mold 1 integrated with the heating plate, and the air bag 5 is covered with the upper mold 1. to form a tire molding hollow part, and pressurizing material is injected into the airbag 5 from the pressurizing port 6 at a pressure of about 20k9/cm.

As a result, the tire bag 5 is inflated and the tire molding member is pressed onto the hollow inner surface of the mold 1, and the grooves of the tread portion 4A are molded by the protrusions 3 of the mold 1. Here, the heating plate is heated to heat the tire molding material and the tire is molded.
At this time, when the tire is attached and vulcanized, the gas and air generated from the tire molding member and the air remaining in the hollow part of the mold 1 are removed to produce a high-quality tire. The mold 1 is evacuated from a vent hole 2 provided in the mold 1 to the outside by a suction machine (not shown).

Conventionally, the air vent holes 2 have a diameter of about 1 to 1.5 holes in a box mold 1 of 1,000 to 150 holes. However, the diameter of the above pores is small, so machining is difficult.
Furthermore, when pressurizing the tire for molding, the tire molding part enters into the vent hole 2 and is molded. As a result, when the upper mold 1 is opened and the tire 4 is taken out after the tire is molded, many small protrusions of the tire molding member are formed on the surface of the tire.
I need to capture this. Although these small protrusions can be easily scraped off and shaped, the tire molding member that has entered the air vent hole 2 is generally left inside the air vent hole 2. For this reason, cleaning the many thin air vent holes 2 is extremely troublesome. In order to solve this problem, it has been proposed to employ a configuration in which a pin is slidably supported within the air vent hole 2. However, as mentioned above, the conventional air vent hole is generally a small hole of about 1 to 1.5 sides, and it is extremely difficult to arrange the pin in the hole so that it can be slid into the hole. The present invention aims to solve the above-mentioned problems, and is configured to have a comparatively large-diameter air vent hole, and to house a cylinder unit in which a punch is attached inside the hole. A gap is provided between the inner diameter of the air vent cylinder constituting the cylinder and the outer diameter of the punch, and the tire molding member is prevented from entering, and the pusher is made slidable so that even if it does enter, it can be easily removed. The purpose is to make it possible.

The invention will now be explained with reference to FIGS. 2a, b and 3 a, b, c. FIGS. 2a and 2b are side cross-sectional sections explaining the structure and function of the air vent in the embodiment of the present invention;
FIG. 3a shows a sectional view of a conventional air vent, FIG. 3b shows a sectional view of an embodiment of the air vent of the present invention, and FIG. 3c shows a sectional view of another embodiment of the air vent.

In the figure, the same symbols as in FIG. 1 represent the same parts, 7 is the air vent cylinder, 7A is the cylinder bottom hole, 7B is the sliding hole, 7c
8 is a shoulder portion, 8 is a spring, 9 is a pressing punch having a coin portion 10, 9A is a pressing head, and 11 is another example of a pressing punch having a protruding strip or a protruding piece 12, respectively. Note that the above components 7, 8, 9, 10, or components 7, 8, 10, 1 1
, 12 constitute the shilling unit referred to in the present application. In the embodiment of the present invention, a vent hole 2 is provided which is larger than the vent hole 2 of the tire molding machine shown in FIG. A cylinder unit with a punch 9 is inserted into the iron.

In other words, the cylinder unit consists of cylinder 7, spring 8, and punch 9.
A cylinder 7 with an outer diameter of 5 to 7 ribs is inserted and fixed in the front part of an air vent hole of the same size, and the cylinder 7 has a sliding plate with a diameter of about 2 sides. A hole 78 is formed, and a press punch 9 that slides in the slide hole 7B is fitted with an iron. is pressed forward, the collar 10 is stopped by the shoulder 7C of the cylinder 7, and the head 9A of the Oshimura 9 is made to slightly protrude into the recess IA of the mold 1. In the same manner as described for the tire molding machine shown in FIG. 6
The tire molding member is pressed into the inner surface of the hollow part of the molds 1, 1 by press-fitting the pressurizing material at a pressure of about 20 kg/1, and the groove of the tread part is molded by the protrusion 3 of the mold 1, and the heating plate ( (not shown) is heated to perform vulcanization.

At this time, as shown in FIG. 2b, the head 9A of the punch 9 protruding into the recess IA of the mold 1 is pressed by the tire molding member and pushed into the cylinder 7 against the spring 8. Pushed in. Then, the gas generated in the tire molding member and the air remaining in the gap between the inner surface of the hollow part of the molds 1 and 1 and the tire molding member are removed from the suction device (
(not shown), etc., to the outside. When vulcanization is completed and the tire 4 is molded, the upper mold 1 is removed and the tire 4 is taken out.

For this reason, in the embodiment of the present invention, the tire molding member, which was conventionally press-fitted into the air vent hole 2 and molded, is hardly press-fitted into the sliding hole 78 and slides slightly. Even if there is a tire molding part that has entered the hole 7B, when the tire 4 is taken out, the force of the spring 8 will cause the punch 9 to protrude into the state shown in FIG. is extruded to the hollow side of the molds 1,1. Therefore, there is almost no need to clean the mold 1, especially the vent hole 2, and the small protrusions that form on the tire 4 can be easily removed by simply grinding them, making it easy to finish the surface of the tire 4. Become. Figures 3a to 3c are cross-sectional views of the air vent hole 2 formed in the mold 1, where a is a secondary air vent hole with a diameter of about 1 rib to 1.5 skins, and b is an embodiment of the present invention. De Oshimura 9
indicates a configuration with a circular cross section, and c indicates an Oshimura 1 on the outer periphery of the Oshimura 11.
1 is located at the center of the sliding hole 7B.
This shows a configuration with 2.

In the embodiment shown in FIGS. 3b and 3c used in the present invention, the area of the gap between the punch 9 or 11 and the sliding hole 7B is set to such an extent that the tire molding member does not enter therein, and that gas can be sufficiently extracted. Set it so that

As a result, according to the present invention, under the same air vent area, the air vent hole 2
The diameter of the vent hole 2 can be increased, making it easy to process the vent hole 2. Although the above-mentioned protrusion or protrusion piece 12 is shown as having four protrusions, it may have three protrusions, six protrusions, etc., as long as the ridge 11 is in the center of the sliding hole 7B.
As detailed above, the present invention is a tire molding method in which a tire molding member is placed in a hollow space formed by two molds, the material is inflated and pressure-bonded to the molds, and a tire is molded by heating and vulcanizing. In the machine, the cylinder unit, which is pre-assembled as a unit, is housed in the air vent hole, so it is easy to attach the press punch to the air vent hole, and the press punch does not intrude into the air vent hole of the tire molding member. Even if they do get in, they will be pushed out by the punch, making it easy to clean the mold. Additionally, the vent holes are much larger in diameter than conventional ones, making machining easier.

[Brief explanation of drawings]

Figure 1 is a side sectional view of the main parts of a conventional tire molding machine, Figure 2a
, b are side sectional views explaining the structure and function of the air vent in the embodiment of the present invention, FIG. 3 a is a sectional view of a conventional air vent, and FIG. Cross section, 3rd
Figure c shows a cross-sectional view of a vent hole in another embodiment of the present invention. In the figure, 1 is the mold, 2 is the vent hole, 3 is the protrusion, 4 is the tire, and 5
air bag, 6 is the pressure inlet, 7 is the cylinder, 8 is the spring,
9 and 11 represent the pusher, 10 represents the collar, and 12 represents the protrusion, respectively. Na Shiryo Z Shiryo 3 legs

Claims (1)

[Claims] 1. A mold having a recess, a plurality of vent holes passing through the recess of the mold and the outside, a tube-shaped air bag to be fitted into a ring-shaped hollow formed by combining the molds, and an outer periphery of the air bag. In a tire molding machine equipped with a heater for heating a produced tire molding member, the cylinder unit is configured to be housed in the air vent hole,
The cylinder unit includes a vent cylinder having an outer diameter that substantially matches the inner diameter of the vent hole, a spring accommodated in a bottom hole of the vent cylinder, and a spring that slides within a sliding hole of the vent cylinder. The spring has one end supported by the lower end of the bottom hole and the other end engaged with the lower end flange of the push rod, and the spring has at least one end supported by the lower end of the bottom hole. The cylinder unit is configured to have a press rod head which is pressed by the spring in the bottom hole and slides in the sliding hole, and the cylinder unit is housed as a unit in the air vent hole. . A tire molding machine, characterized in that a ring-shaped gap is formed between the inner diameter of the air vent cylinder and the outer diameter of the push rod head.