Fluid expandable tire building drum

• US 4,148,682 A
• Filed: 07/05/1977
• Issued: 04/10/1979
• Est. Priority Date: 07/05/1977
• Status: Expired due to Term

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Collins, Marcus H., Patel, Kiritkumar R.
• Primary Examiner(s): Kittle, John E.
• Application Number:
  US05/813,153
• Time in Patent Office: 644 Days
• Field of Search: 156/123, 156/126, 156/127, 156/128, 156/129, 156/133, 156/394, 156/414-420, 92/92, 92/98 R, 92/99, 92/100, 92/103 F, 92/103 SD, 152/350, 152/169, 152/172, 152/179, 152/182, 152/208, 152/216, 152/223, 152/228
• US Class Current: 156/416
• CPC Class Codes: B29D 30/242 for manufacturing substantially cylindrical tyre components without cores or beads, e.g. treads or belts

Abstract

A fluid expandable drum for building portions of tires in a tire building machine includes an annular supporting drum and an expandable annular tube element having an inner peripheral surface supported on the annular drum. The tube element includes an outer peripheral surface upon which building means is secured for movement therewith. The building means define an annular building surface thereon which is movable in a radial direction toward and away from the annular support drum upon contraction and expansion, respectively, of the tube element. The tube element is expanded to expand the diameter of the building surface to enable a tire portion to be built thereon and retracted to decrease the diameter of the building surface to enable a built tire portion to be removed therefrom. The tube element includes a radial ply extending around the cross-sectional circumference of the tube elements and a radial ply band extending around the outer peripheral surface of the tube element adjacent the building means to increase the strength and resiliency of the outer peripheral surface to enable the building means to decrease the diameter of the building surface upon contraction of the tube element without the need for auxiliary springs.

Claims

1. A fluid expandable drum for building a tread and a radial tread ply band in a tire building machine comprising an annular support drum having an annular outer surface thereon, an expandable annular tube element having an inner peripheral surface supported on said annular outer surface of said support drum and an outer annular peripheral surface, building means movable with said outer annular peripheral surface of the tube element and defining an annular building surface thereon which is movable in a radial direction toward and away from said annular support drum upon contraction and expansion, respectively, of said tube element, said tube element being expanded to expand the diameter of said building surface to enable a tread and a radial tread ply band to be built thereon and contracted to decrease the diameter of said building surface to enable a built tread and radial tread ply band to be removed therefrom, said tube element including a radial ply extending around the cross-sectional circumference of the tube element and a radial ply band extending around said outer peripheral surface of said tube element to increase the strength and resiliency of the outer peripheral surface to enable said building surface defined by said building means to decrease in diameter upon contraction of said tube element, said tube element further including an inner interior surface, an outer interior surface, and an annular filler block disposed on said inner interior surface for decreasing the volume of said tube element to decrease the volume of the fluid needed to expand the tube element to a predetermined diameter, said filler block further acting to add rigidity to said inner peripheral surface and said inner interior surface to prevent sagging in a radially outwardly direction of said outer peripheral and outer interior surfaces upon contraction of said tube element.

2. A fluid expandable drum for building a tread and a radial tread ply band in a tire building machine as defined in claim 1 wherein said annular filler block is spaced a predetermined distance from said outer interior surface of said tube element and is positioned to engage said outer interior surface of said tube element when said tube element is contracted.

3. A fluid expandable drum for building a tread and a radial tread ply band in a tire building machine as defined in claim 1 where said annular tube element includes a rubber exterior cover which defines said inner and outer peripheral surfaces and a rubber inner layer which defines said inner and outer interior surfaces, said radial ply being disposed between said rubber exterior cover and said rubber inner layer.

4. A fluid expandable drum for building a tread and a radial tread ply band in a tire building machine as defined in claim 2 wherein said annular tube element includes a rubber exterior cover which defines said inner and outer peripheral surfaces and a rubber inner layer which defines said inner and outer interior surfaces, said radial ply being disposed between said rubber exterior cover and said rubber inner layer.

5. A fluid expandable drum for building a tread and a radial tread ply band in a tire building machine as defined in claim 4 wherein said radial ply band is disposed between said rubber exterior cover defined by said outer peripheral surface and said radial ply, said radial ply band being disposed adjacent said building means to increase the strength and resiliency of the portion of the tube element adjacent said building means without similarly increasing the strength and resiliency of the remaining portion of the tube element.

6. An annular fluid expandable tube element for use with an annular drum for building portions of tires in a tire building machine comprising a lower wall portion having an inner surface and an outer surface adapted to be supported on the drum, an upper wall portion having an inner surface and an outer surface, said upper wall portion being movable radially outwardly from said lower wall portion upon expansion of the tube element and being movable radially toward said lower wall portion upon contraction of said tube element, support means movable with said outer surface of said upper wall portion and defining an annular building surface thereon which is movable in a radial direction away from the drum upon expansion of the tube element to expand the diameter of the building surface to enable a portion of a tire to be built thereon and movable in a radial direction toward the drum upon contraction of the tube element to decrease the diameter of the building surface to enable a built tire portion to be removed therefrom, a radial ply extending around the transverse cross-sectional circumference of the tube element, a radial ply band extending around the circumference of the tube element in the upper wall portion to increase the strength and resiliency of the outer surface of the upper wall portion to enable said support means to decrease the diameter of the building surface upon contraction of the tube element without the need for auxiliary spring means which provide retraction of the support means upon retraction of the tube element and an annular filler block disposed on said inner surface of said lower wall portion for decreasing the volume of said tube element to decrease the volume of the fluid needed to expand the tube element to a predetermined diameter, said filler block further acting to add rigidity to said lower wall portion to prevent sagging in a radially outwardly direction of said upper wall portion upon contraction of said tube element.

7. An annular fluid expandable tube element for use with an annular drum for building portions of tires in a tire building machine as defined in claim 6 wherein said annular filler block is spaced a predetermined distance from said inner surface of said upper wall portion and is positioned to engage said inner surface of said upper wall portion upon contraction of said tube element.

8. An annular fluid expandable tube element for use with an annular drum for building portions of tires in a tire building machine as defined in claim 7 wherein said outer surface of said upper and lower wall portions includes a rubber cover layer and said inner surfaces of said upper and lower wall portions include a further rubber cover layer, said radial ply being disposed between said rubber cover layer and said further rubber cover layer, and said radial ply band being disposed in said upper wall portion adjacent said support means between said rubber cover layer and said radial ply.