Claims
- 1. A process for manufacturing a heavy duty low-section pneumatic radial tire, which comprises the steps of:
- forming a first green case in which a ply for a carcass is placed on an outer circumference of a first drum and said ply is turned around each of a bead core and a stiffener at each side of the ply so as to sandwich a stiffener above each bead core between the ply and a ply turnup portion thereof, applying a sidewall rubber layer thereto; forming a second green case in which one or plural steel cords are spirally wound directly on a second drum with an outer profile substantially corresponding to the carcass form when the tire to be manufactured is mounted on a rim and inflated at a given internal pressure and being capable of contracting the outer profile to form a second belt layer for belt; said second belt layer having a bearing ratio on resistance to tensile load per unit width larger than that of a first nonspiral form belt layer, and stacking said first belt layer and a tread rubber layer successively on said second belt layer;
- forming a green tire casing assembly in which the first green case removed from the first drum is inserted into the inside of the second green case removed from the second drum, said first and second green cases being in alignment with each other to comprise a green tire casing assembly and, the resulting green tire casing assembly brought to a toroidal form; and
- placing the green tire casing assembly of green tire casings in a vulcanizer to conduct the curing thereof.
- 2. The process according to claim 1, wherein said sidewall rubber layer is combinationally extruded together with a cushion rubber to be located at its one end.
- 3. The process of claim 1 wherein the step of applying a sidewall rubber layer comprises the steps of laminating a pair of rubber layers to portions of said carcass ply and said turnup portions thereof.
- 4. The process of claim 3 further comprising the step of placing a wire chafer over said turned up portions prior to laminating said sidewall rubber layers.
- 5. The method of claim 1 wherein the cords wound on said second drum comprise bias cords turned around said second drum and having ends overlapped with each other.
- 6. The method of claim 1 wherein said first belt layer comprises two cord plies having cords crossed with each other.
Priority Claims (1)
Number |
Date |
Country |
Kind |
57-230059 |
Dec 1982 |
JPX |
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Parent Case Info
This is a continuation of Ser. No. 834,123, filed on Feb. 26, 1986, now U.S. Pat. No. 4,702,293, which is a continuation of Ser. No. 564,046, filed on Dec. 21, 1983, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0598767 |
Mar 1978 |
SUX |
Continuations (2)
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Number |
Date |
Country |
Parent |
834123 |
Feb 1986 |
|
Parent |
564046 |
Dec 1983 |
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