Molded polypropylene foam tire cores

• US 5,073,444 A
• Filed: 01/11/1990
• Issued: 12/17/1991
• Est. Priority Date: 01/11/1990
• Status: Expired due to Fees

• Current Assignee: Dennis A. Shanelec
• Original Assignee: Dennis A. Shanelec
• Inventors: Shanelec, Dennis A.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US07/463,458
• Time in Patent Office: 705 Days
• Field of Search: 521/56, 521/60, 152/310, 428/413-415
• US Class Current: 428/313.5
• CPC Class Codes: B29C 44/3426 Heating by introducing steam in the mould
• CPC Class Codes: B29C 44/445 in the form of expandable granules, particles or beads
• CPC Class Codes: B29D 30/02 Solid tyres ; Moulds therefor
• CPC Class Codes: B60C 7/1015 using foam material
• CPC Class Codes: C08J 9/232 by sintering expandable particles
• CPC Class Codes: Y10T 152/10378 Casing enclosed core
• CPC Class Codes: Y10T 152/10432 Sectional transversely
• CPC Class Codes: Y10T 428/249972 Resin or rubber element

Abstract

A molded polypropylene foam tire core suitable for all types of wheels. The core may be inserted, in one or more sections, into a pneumatic-type tire casing and mounted on a wheel rim to provide puncture-proof and rupture-proof internal support for said tire casing.

Claims

1. A tire core for use in a vehicle tire casing, said tire core consisting of:

at least (one) two arcuate segments, formed prior to insertion into said casing, of molded polypropylene foam beads fused together by steam and shrunk so that, when said segments are inserted in said casing, said segments will expand and be held in compression by said casing.

2. The tire core of claim 1 wherein:

said polypropylene foam beads are formed of polymers selected from the group consisting of;

polypropylene homopolymer,

ethylene-polypropylene random copolymer,

ethylene-polypropylene-butene-1 random copolymer,

polypropylene-ethylene block copolymer,

silane-modified polypropylene, and

crosslinked products of these polymers.

3. The tire core of claim 1 wherein:

said steam was pressurized steam.

4. The tire core of claim 1 wherein:

the fused polypropylene foam beads are composed of a polymer blend of the polymers set forth in claim 2.