JPH0722930B2 - Hollow wheel and its manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a hollow wheel and a manufacturing method thereof.

Conventional technology Conventionally, the paddy wheel disclosed in Japanese Utility Model Publication No. 54-50067 is
The tire was simply burnt on the entire circumference of the rim to form a solid solid type wheel. However, recently, this conventional paddy wheel has a drawback that it often vibrates when traveling on the road, and recently, pneumatic paddy wheels have come to be used. The pneumatic wheel had a structure in which the tire 4 was attached to the annular rim of the wheel, as disclosed in Japanese Utility Model Publication No. 59-9922. However, in such a configuration, when the air in the tire is reduced, it cannot be used, and from the joint between the tire and the rim,
There was a drawback that muddy soil entered. Therefore, the development of paddy wheels that confine air in a solid tire that molds the tire around the rim is required, and a paddy wheel of the form disclosed in No. 55-144104 was devised. It was difficult to put it into practical use due to the difficulty of the manufacturing method.

Problems to be Solved by the Invention The present invention makes it possible to manufacture a hollow wheel that has not been practically available in the related art.

Means and Method for Solving Problems In order to solve the above problems, the present invention provides a semi-cracked tire 1a in which a recess into which the wheel rim 7 is fitted and a recess to be a cavity are formed on the joint surface side. , 1b face each other so that they are joined to each other on the joining surface side, and the rim 7 of the wheel is placed in the recessed portions of both, and the hollow portion is vulcanized by applying internal pressure to the hollow portion while heating with the mold. A cracked tire 1a, 1b is fusion-bonded to a rim 7 of a wheel to form a hollow wheel in which a hollow portion (c) is formed at a portion continuous or isolated from the rim fusion portion. The semi-cracked tires 1a and 1b, which are not vulcanized or slightly vulcanized, in which a concave portion into which 7 is fitted and a concave portion which becomes a hollow portion are formed on the joint surface side are molded by a molding die, and then the half cracks are formed. -Shaped tires 1a and 1b are opposed to each other so that the joint surfaces are joined to each other, and the wheel rim 7 is inserted into the recesses of the two. In the state of being arranged, while heating with a molding die, internal pressure is applied to the cavity to vulcanize, and the semi-cracked tires 1a and 1b are fusion-bonded to the rim 7 of the wheel. This is a method for manufacturing a hollow wheel in which a hollow portion (c) is formed in a continuous or separated portion.

EFFECTS OF THE INVENTION Since the present invention has the above-described hollow wheel and a method for manufacturing the hollow wheel, it has become possible to manufacture a hollow wheel that could not be practically used in the past. In the manufactured hollow wheel, since the hollow portion (C) is formed during vulcanization, the material is saved and vibrations are not absorbed by the unevenness of the road surface during traveling, and the inner hollow portion (C) is not formed. It can be used with the same feeling as a conventional solid tire without inflating the air pressure by putting compressed air into it, and it becomes a wheel that does not need to support the airframe weight of the airframe like a conventional pneumatic tire. When it is attached, even if nails or the like stand in the tire portion during traveling, the vehicle can travel without significantly deteriorating the traveling performance, the work can be continued, and the work efficiency is extremely improved.

Examples 1a and 1b are tires in an unvulcanized state or a semi-vulcanized state. Two tires, a right side tire and a left side tire, are prepared. In this embodiment, a left and right substantially symmetrical shape is prepared, but it does not matter whether or not this is symmetrical. However, the surfaces to be joined facing each other are symmetrical. The manufacture of this tire 1 is
The first mold 2 shown in FIGS. 4 to 11, the core 4 shown in FIGS. 9 and 10 and the second mold 3 shown in FIGS.
When combining as shown in Fig. 12 and Fig. 12, put an unvulcanized rubber piece (a) in the hollow part, pressurize it and heat the mold to about 120 ° C to 170 ° C for about 1 to 3 minutes. Then, the molded tires 1a and 1b inside are taken out and manufactured in a state where they are hardly vulcanized. The inner peripheral surfaces of the first and second molds 2 and 3 determine the lug shape, and in the illustrated example, the lug forming concavo-convex portion surfaces 2a and 3 are formed so that substantially symmetrical lugs are formed on the left and right.
a is provided. The core 4 is set in the space between the first mold 2 and the third mold 3 as described above,
The first convex surface 4a, 4b forming the air reservoir in a left-right symmetrical manner and the second convex portion 4 forming a hollow portion for fitting a wheel rim described later.
b, 4b are formed, and the surface of the core 4 is subjected to a surface treatment such as a fluorine resin so that the core 4 can be easily taken out.

In this way, when the tires 1a and 1b are formed, next,
When the first mold 2 and the second mold 3 are separated from each other, the core 4 is easily detached and taken out due to the above-mentioned surface treatment, and the unvulcanized molded tire is placed on the first or second mold side. Attach and leave.

On the other hand, apart from the tires 1a and 1b, as shown in FIG.
An iron wheel bone 8 having a spoke 6 protruding in a radial direction from a boss 5 which is fixed by being inserted into an axle of a working machine and a rim 7 having a circular cross section fixed to a tip thereof is configured. Then, as shown in FIG. 15, the rim 7 of the wheel bone 8 is the second portion of the core 4.
Recesses (b) of the tires 1a, 1b molded with the protrusions 4b, 4b,
The mold 2 and the mold 3 are assembled again as shown in FIG. 15 so that they are fitted in (b).

In this state, the mold is heated to about 150 ° C to 200 ° C for a while to vulcanize the unvulcanized rubber inside, and during this vulcanization, pressurized air or Pressurized steam is blown by the air blowing tube 9 and the tubular needle 10 so that both tires are welded and vulcanized.
The air pressure of the pressurized air is suitably 8 to 10 kg / cm ² .

When the vulcanization is completed in this way, the blowing of the pressurized air is stopped, the internal pressure in the cavity (c) is released from the air blowing pipe 9 and returned to almost normal pressure, and then the tubular needle 10 is removed, The molds 2 and 3 are opened, and the axle A having the tire fused around the rim 7 is taken out and manufactured.

As a wheel manufactured by this manufacturing method, a wheel having a structure shown in FIG. 19 or 20 can be considered. This former one
The wheel of FIG. 19 has a structure in which the apex of the wheel rim 7 is brought close to the hollow portion (c), and the latter wheel of FIG. 20 has a structure in which the rim 7 is positively exposed in the hollow portion (c). belongs to.

In the above example, it is not always necessary to blow pressurized air or pressurized steam, and it is only necessary to apply an internal pressure to the hollow portion. Therefore, the hollow portion (c) is vulcanized before the vulcanization molding process. If an agent (foaming agent) that generates gas is added, the air blowing pipe 9 and the tubular needle 10 can be omitted.

Further, in the above example, two left and right unvulcanized tires 1a and 1b were simultaneously molded using the core 4, but left and right unvulcanized tires
Of course, 1a and 1b may be manufactured. In this case, a wheel with blades provided with a wide range of propulsion lugs can be easily molded, and injection molding of unvulcanized rubber is possible as shown in Fig. 18. Is.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIGS. 1, 5, and 9 are side views showing a part of a mold, and FIGS.
FIG. 4 is a sectional view taken along the lines AA, BB, and CC of FIG. 1, and FIG.
Figures 8 to 8 are sectional views of DD, EE, and FF in FIG. 5, respectively.
FIG. 10 is a sectional view taken along the line GG in FIG. 9, and FIGS. 11 and 12 are sectional views showing the main part of the step of molding a tire piece, FIG. 13 (a), and FIG.
13 (b) is a cross-sectional view of the processed unvulcanized rubber tire piece,
FIG. 14 is a side view of a wheel bone, FIG. 15 is a cross-sectional view of a main part at the time of wheel molding, and FIG. 16 is a side view showing a part of a completed wheel,
FIG. 17 is a perspective view showing a part of a wheel, FIG. 18 is a cross-sectional view of a main part when an unvulcanized tire piece of another example is manufactured, and FIGS. 19 and 20 are manufacturing processes of the present invention. The principal part sectional drawing of the wheel of another example manufactured by the method is shown. Reference numerals 1a and 1b in the figure are tires, 2, 3 and 4 are molds, 7 is a rim, 8 is a wheel bone,
A is a wheel, (a) is an unvulcanized rubber piece, and (c) is a cavity.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location B29L 30:00 (72) Inventor Riji Shimamoto 1 Yakura, Tobe, Iyo-gun, Ehime Prefecture Examiner in the Engineering Department Shimako Kato (56) References JP 62-95978 (JP, A)

Claims (2)

[Claims] 1. A semi-cracked tire 1a, 1b in which a recess into which a wheel rim 7 is fitted and a recess serving as a cavity are formed on the joint surface side.
Are made to face each other so that the joint surface sides are joined to each other and the wheel rim 7 is placed in the concave portions of both, and the hollow portion is vulcanized by applying internal pressure to the hollow portion while heating with a molding die. A hollow wheel in which tires 1a, 1b are fusion-bonded to a rim 7 of a wheel, and a cavity (c) is formed in a portion continuous or isolated from the rim fusion-bonded portion. 2. Unvulcanized or slightly vulcanized semi-cracked tires 1a, 1b in which a concave portion into which a wheel rim 7 is fitted and a concave portion to be a hollow portion are formed on a joint surface side are formed by a molding die. After molding, the semi-cracked tires 1a, 1b are made to face each other so that the joint surfaces are joined to each other, the rim 7 of the wheel is placed in the recesses of both, and the hollow portion is heated by the molding die. A hollow wheel in which internal pressure is vulcanized to vulcanize it and the semi-cracked tires 1a and 1b are fusion-bonded to the rim 7 of the wheel, and a cavity (c) is formed at a portion continuous or isolated from the rim fusion portion Manufacturing method.