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US3979249A Expired / Lapsed US ⏱️ 0.0 years remaining

Tire building apparatus

Assignee: Dunlop Ltd
•
Filing: 1974-08-20
•
Granted: 1976-09-07
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Expires: 1994-08-20
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Abstract

Abstract An inflatable shaping bag or diaphragm for a tire building or shaping former. The bag is based on an elastomeric sheet radially expansible but has high lateral bending stiffness in part of its width owing to the presence of at least one pair of reinforcements of inextensible reinforcing elements, each element lying in a plane containing the axis of the bag. The reinforcement can consist, for example, of two layers of parallel steel cords, spaced apart by a layer of rubber.

Inventors

  • 👤 Ernest George Nicholls
  • 👤 Bernard Charles Allitt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:32
CPC Classifications
B; B29; B29D; B29D30/00; B29D30/06; B29D30/08; B29D30/20; B29D30/24; B29D30/26; B29C; B29C33/00; B29C33/38; B29C33/40; B29C33/405; B29C33/44; B29C33/48; B29C33/50; B29C43/00; B29C43/32; B29C43/36; B29C43/3642; B29K; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/10; B29K2105/101; B29L; B29L2022/00; B29L2022/02; B29L2022/025; B29L2030/00

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 152 words
An inflatable shaping bag or diaphragm for a tire building or shaping former which is expansible in a radial direction to effectively increase the diameter of at least a portion thereof to a substantially toroidal configuration comprising a flexible elastomeric sheet material and, in at least one circumferentially extending region, a means for reinforcing said region to have a high lateral bending stiffness while remaining radially expansible, said means comprising at least one pair of layers of substantially inextensible reinforcing elements lying in planes including the axis of the bag or diaphragm said elements providing a high stiffness in said planes, the layers of each pair being radially spaced apart and separated from one another by a layer of elastomeric material thereby creating a beam-like structure having a high lateral bending stiffness resulting in the outside shape of the bag or diaphragm in said planes being substantially flat in said reinforced regions.
Claim 2
Dependent Claim 152 words
An inflatable shaping bag or diaphragm for a tire building or shaping former which is expansible in a radial direction to effectively increase the diameter of at least a portion thereof to a substantially toroidal configuration comprising a flexible elastomeric sheet material and, in at least one circumferentially extending region, a means for reinforcing said region to have a high lateral bending stiffness while remaining radially expansible, said means comprising at least one pair of layers of substantially inextensible reinforcing elements lying in planes including the axis of the bag or diaphragm said elements providing a high stiffness in said planes, the layers of each pair being radially spaced apart and separated from one another by a layer of elastomeric material thereby creating a beam-like structure having a high lateral bending stiffness resulting in the outside shape of the bag or diaphragm in said planes being substantially flat in said reinforced regions.
Claim 3
Dependent Claim 80 words
A bag or diaphragm according to claim 1 in which the reinforcement is strips of rigid material of greater depth than width disposed side by side as a layer in a region forming a band round the diaphragm, the depth of the strips giving the strips a high stiffness in the plane containing the axis of the bag or diaphragm while the lower width of the strips and thickness of rubber between the strips allows the layer to be expanded.
Claim 4
Dependent Claim 15 words
A bag or diaphragm according to claim 1 in which the reinforcing elements are tubes.
Claim 5
Dependent Claim 20 words
A bag or diaphragm according to claim 3 in which the tubes are located about cords extending across the diaphragm.
Claim 6
Dependent Claim 22 words
A bag or diaphragm according to claim 1 in which the reinforcement comprises steel cords or wires extending laterally of the diaphragm.
Claim 7
Dependent Claim 26 words
A bag or diaphragm according to claim 1 in which the region containing the reinforcement is the center or crown region of the bag or diaphragm.
Claim 8
Dependent Claim 33 words
A bag or diaphragm according to claim 6 wherein the axial width of the reinforcement is no greater than the axial width of a breaker layer of a tire to be shaped thereon.
Claim 9
Dependent Claim 23 words
A bag or diaphragm according to claim 6 in which one or both of the laterally outer regions thereof also contain the reinforcement.
Claim 10
Dependent Claim 37 words
A bag or diaphragm according to claim 1 in which the reinforcement comprises a plurality of pairs of layers separated by laterally flexible regions to achieve a desired cross-sectional shape when the bag or diaphragm is inflated.
Claim 11
Dependent Claim 17 words
A bag or diaphragm according to claim 9 in which lateral flexible regions consist of unreinforced elastomer.
Claim 12
Dependent Claim 25 words
A bag or diaphragm according to claim 9 in which the laterally flexible regions contain layers of flexible reinforcing elements which are not spaced apart.
Claim 13
Dependent Claim 21 words
A bag or diaphragm according to claim 1 which included at least one ply of additional reinforcing elements which are flexible.

References Cited (Backward Citations)

US2084009A Cited
US2814331A Cited
US3018213A Cited
GB1000262A Cited
US3138510A Cited
US3265549A Cited
US3547734A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-09-07 1980-03-08 1980-09-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-09-07 1984-03-08 1984-09-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-09-07 1988-03-08 1988-09-07 $7700.00 Window Closed / Lapsed

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