Patent US4105482A successfully refreshed from Google Patents.
US4105482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of vulcanizing a prevulcanized tread
Assignee: TRAPPE LIESELOTTE
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Filing: 1975-04-28
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Granted: 1978-08-08
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Expires: 1995-04-28
Abstract
Abstract A method for retreading a tire carcass having an arcuate crown with a transversely flat, prevulcanized profiled tread comprising applying the tread to the crown of the carcass with an intermediate layer of unvulcanized bonding rubber therebetween thereby deforming the tread to conform to the crown while preventing the occlusion of air between the tread and carcass, securing an elastic, pressure-permeable fabric or elastomeric stressing belt annularly around the assembled tread and carcass and vulcanizing the intermediate layer of bonding rubber by applying heat and pressure while preventing deformation of the carcass, slippage or raised edges of the tread and uneven distribution of the bonding rubber layer. Also disclosed are a stressing belt and an autoclave structure and method of autoclave operation for use in the above-described method.
Inventors
- 👤 Friedrich-Wilhelm Wapelhorst
- 👤 Heinz-Dieter Kalkoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:01
CPC Classifications
B; B29; B29D; B29D30/00; B29D30/06; B29D30/52; B29D30/54; B29D30/542; B29C; B29C35/00; B29C35/02; B29C35/0227; B29C35/0233; B29D30/56; B29D2030/545; B29D30/58; B29D2030/582; B29L; B29L2030/00; Y; Y10; Y10S; Y10S156/00; Y10S156/909
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
342 words
A method for retreading a tire carcass having an arcuate tread engaging crown with a prevulcanized annular tread having a pattern of ribs and grooves on its exterior road enaging surface and a substantially flat interior cross sectional configuration when in the unstressed state; said method comprising: (a) applying the tread to the crown of the carcass with an unvulcanized bonding rubber intermediate layer therebetween, the tread being elastically deformed to conform to the carcass crown, the application of the tread to the carcass being effected in such a manner that the occlusion of air between the tread and the carcass is avoided; (b) securing a stressing belt annularly around the assembled tread and carcass, said stressing belt being an elongated endless band extending annularly around the road engaging surface of the assembled tread with its longitudinal direction running in the same direction as the tread and its width corresponding at least to that of the tread, the belt having openings to allow a surrounding fluid to pass therethrough to at least some of the road engaging surface of the tread so that the pressure of the fluid is transmitted to all of the ribs and grooves of the tread, said belt further being elastic, secured annularly around the tire and pressed thereagainst by shrinkage in its longitudinal direction under the influence of heat and moisture thereby providing around the longitudinal direction of the tread a uniform, radially inwardly directed stress to hold the elastically deformed tread on the carcass, said belt further being capable of withstanding elevated temperatures and pressures sufficient to vulcanize said bonding rubber intermediate layer; (c) vulcanizing the intermediate layer of bonding rubber by subjecting the tread and carcass assembly with the fluid-permeable, shrinkable and elastic stressing belt therearound to the action of heat and pressure in an enclosed chamber whereby as the adhesive power of the intermediate layer of bonding rubber decreases during heating prior to vulcanization, the tread is held securely in position and distortion of the carcass or of the bonding rubber layer is avoided.
Claim 2
Independent Claim
342 words
A method for retreading a tire carcass having an arcuate tread engaging crown with a prevulcanized annular tread having a pattern of ribs and grooves on its exterior road enaging surface and a substantially flat interior cross sectional configuration when in the unstressed state; said method comprising: (a) applying the tread to the crown of the carcass with an unvulcanized bonding rubber intermediate layer therebetween, the tread being elastically deformed to conform to the carcass crown, the application of the tread to the carcass being effected in such a manner that the occlusion of air between the tread and the carcass is avoided; (b) securing a stressing belt annularly around the assembled tread and carcass, said stressing belt being an elongated endless band extending annularly around the road engaging surface of the assembled tread with its longitudinal direction running in the same direction as the tread and its width corresponding at least to that of the tread, the belt having openings to allow a surrounding fluid to pass therethrough to at least some of the road engaging surface of the tread so that the pressure of the fluid is transmitted to all of the ribs and grooves of the tread, said belt further being elastic, secured annularly around the tire and pressed thereagainst by shrinkage in its longitudinal direction under the influence of heat and moisture thereby providing around the longitudinal direction of the tread a uniform, radially inwardly directed stress to hold the elastically deformed tread on the carcass, said belt further being capable of withstanding elevated temperatures and pressures sufficient to vulcanize said bonding rubber intermediate layer; (c) vulcanizing the intermediate layer of bonding rubber by subjecting the tread and carcass assembly with the fluid-permeable, shrinkable and elastic stressing belt therearound to the action of heat and pressure in an enclosed chamber whereby as the adhesive power of the intermediate layer of bonding rubber decreases during heating prior to vulcanization, the tread is held securely in position and distortion of the carcass or of the bonding rubber layer is avoided.
Claim 3
Dependent Claim
201 words
A stressing belt for use in retreading a tire carcass having an arcuate tread engaging crown wherein a prevulcanized annular tread having a pattern of ribs and grooves on its exterior road engaging surface and a substantially flat interior cross sectional configuration is assembled on the crown with an intermediate layer of unvulcanized bonding rubber therebetween, said belt being an elongated, endless band extending annularly around the road engaging surface of the assembled tread with its longitudinal direction running in the same direction as the tread and its width corresponding at least to that of the tread, the belt having openings to allow a surrounding fluid to pass therethrough to at least some of the road engaging surface of the tread so that the pressure of the fluid will be transmitted to all of the ribs and grooves of the tread, said belt further being elastic, secured annularly around the tire and pressed thereagainst by shrinkage in its longitudinal direction under the influence of heat and moisture thereby providing around the longitudinal direction of the tread a uniform, radially inwardly directed stress, said belt further being capable of withstanding elevated temperatures and pressures sufficient to vulcanize said bonding rubber intermediate layer.
Claim 4
Dependent Claim
201 words
A stressing belt for use in retreading a tire carcass having an arcuate tread engaging crown wherein a prevulcanized annular tread having a pattern of ribs and grooves on its exterior road engaging surface and a substantially flat interior cross sectional configuration is assembled on the crown with an intermediate layer of unvulcanized bonding rubber therebetween, said belt being an elongated, endless band extending annularly around the road engaging surface of the assembled tread with its longitudinal direction running in the same direction as the tread and its width corresponding at least to that of the tread, the belt having openings to allow a surrounding fluid to pass therethrough to at least some of the road engaging surface of the tread so that the pressure of the fluid will be transmitted to all of the ribs and grooves of the tread, said belt further being elastic, secured annularly around the tire and pressed thereagainst by shrinkage in its longitudinal direction under the influence of heat and moisture thereby providing around the longitudinal direction of the tread a uniform, radially inwardly directed stress, said belt further being capable of withstanding elevated temperatures and pressures sufficient to vulcanize said bonding rubber intermediate layer.
Claim 5
Dependent Claim
36 words
A method as recited in claim 1 wherein the contact pressure between the tread and the stressing belt is increased by inflating the tire carcass to a pressure greater than the pressure in the pressure chamber.
Claim 6
Dependent Claim
19 words
A method as recited in claim 3 wherein the pressure is produced by internal pressure heating within the carcass.
Claim 7
Dependent Claim
64 words
A method as recited in claim 1 wherein the tread is initially formed as a flat strip which is cut to length, the ends of the cut strip are joined to form an annular tread and a band is placed over the tread joint and firmly connected to the tread on either side of the joint by means of clips inserted into the tread.
Claim 8
Dependent Claim
24 words
A method as recited in claim 1 wherein additional bonding rubber strips are placed on the carcass in the area below the tread edges.
Claim 9
Dependent Claim
28 words
A method as recited in claim 1 wherein the portions of the tire carcass adjacent the tread edge area are trimmed and replaced by an unvulcanized rubber wedge.
Claim 10
Dependent Claim
16 words
A stressing belt as recited in claim 2 wherein said belt comprises a polyester fiber fabric.
Claim 11
Dependent Claim
16 words
A stressing belt as recited in claim 2 wherein said belt comprises a polyamide fiber fabric.
Claim 12
Dependent Claim
38 words
A stressing belt as recited in claim 2 wherein said belt comprises woven elastic fabric, said fabric being woven in such a manner that it effects stress compensation by distributing local stress peaks around the entire belt periphery.
Claim 13
Dependent Claim
17 words
A stressing belt as recited in claim 2 wherein said belt is reinforced with diagonal fabric layers.
Claim 14
Dependent Claim
36 words
A stressing belt as recited in claim 2 wherein the angle between interwoven fabric threads at the center of said belt is different from the angle between interwoven fabric threads at the edges of the belt.
Claim 15
Dependent Claim
34 words
A stressing belt as recited in claim 10 wherein the elasticity of said belt is varied across the width of the belt by varying the density of the fiber arrangement in the belt fabric.
Claim 16
Dependent Claim
16 words
A stressing belt as recited in claim 2 wherein said belt comprises a perforated elastomeric web.
Claim 17
Dependent Claim
33 words
A stressing belt as recited in claim 14 wherein the elasticity of said belt is varied across the width of the belt by varying the density of the perforations in said elastomeric web.
Claim 18
Dependent Claim
33 words
A stressing belt as recited in claim 2 wherein said belt is wider than the width of the contact surface of the tread to enable the belt to receive a side ring profile.
Claim 19
Dependent Claim
36 words
A stressing belt as recited in claim 2 wherein said belt comprises a woven fabric of substantially inelastic fibers, and the elasticity of the belt is due to the manner in which the fibers are woven.
Claim 20
Dependent Claim
35 words
A stressing belt as recited in claim 2 wherein the tensile force exerted by the belt increases from the center to the edges of the belt in the transverse direction of the belt and tread.
Claim 21
Dependent Claim
52 words
A stressing belt as recited in claim 2 wherein said belt comprises an elongated strip provided with metal buttons at one end and a plurality of sets of buttonholes spaced different distances from the other end of said strip whereby the ends can be joined to provide annular belts of varying size.
Claim 22
Dependent Claim
35 words
A stressing belt as recited in claim 2 wherein said belt is manufactured in one piece with reinforcements on the sides whereby the width of the belt is adapted to the width of the tread.
Claim 23
Dependent Claim
17 words
A stressing belt as recited in claim 2 wherein said belt compises a plurality juxtaposed belt portions.
Claim 24
Dependent Claim
35 words
A stressing belt as recited in claim 21 wherein said belt comprises two separate complimentary belt portions which overlap one another in the center of the tread when placed around a carcass and tread assembly.
Claim 25
Dependent Claim
30 words
A stressing belt as recited in claim 22 wherein the overlapping portions of said belt portions are provided with interengaging, longitudinally oriented grooves on the top and bottom surfaces thereof.
Claim 26
Dependent Claim
87 words
A stressing belt as recited in claim 2 wherein said belt comprises a band adapted to be placed over a tread joint; said band being provided on one side thereof with a plurality of clips adapted to be inserted into the tread on either side of the joint; said band being further provided on the other side thereof, with a plurality of buttons whereby said band is secured to the remainder of said belt by engaging the buttons through buttonholes formed in the remainder of the belt.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-07 | 1982-02-06 | 1982-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-07 | 1986-02-06 | 1986-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-07 | 1990-02-06 | 1990-08-08 | $7700.00 | Window Closed / Lapsed |