摘要:
A green tyre disposed on a toroidal support is introduced into a vulcanisation mould. The mould is closed through axial approaching of a pair of half shells acting against the sidewalls and the tread band of the tyre. Circumferential sectors set to operate against the tyre tread band are maintained spaced apart from the tread band itself during admission of a working fluid designed to press the tyre against the toroidal support. Subsequently the sectors are centripetally approached to cause penetration of forming ridges movable in through slits into the tread band, concurrently with a step of full moulding and vulcanisation of the tyre carried out through admission of steam under pressure into the tyre itself.
摘要:
An object of the present invention is to provide a bladder which is unlikely to have a shapal variation along the inner wall surface of the tire and can satisfactorily extend along the inner wall surface of the tire. An inventive bladder is used to press the inner wall surface of the tire by a pressurized heating medium during the vulcanization of a green tire and is comprised of a fabric layer (purl stitched fabric layer 12) and rubber layers (silicone rubber layers 11, 13) placed one over another. Elongation rates of the fabric layer in warp direction and in weft direction both exceed 15% and satisfy: 0.4≦elongation rate in weft direction/elongation rate in warp direction ≦6.0. Since the fabric layer has good extensibility, it can elongate with the rubber layers.
摘要:
A device for the moulding and vulcanization, in predetermined conditions of temperature and pressure, of an at least partially green tyre having a defined volume, said device comprising an outer shell and a collapsible inner support, in which said device also comprises a movable crown interposed between said inner support and said outer shell, said movable crown forming, with said outer shell, a cavity of controlled volume for the moulding and vulcanization of said tyre, the volume of said cavity adapting to the volume of the tyre it contains, so that said moulding pressure is maintained within a predetermined range of values. The invention also relates to a method of moulding and vulcanization at controlled volume.
摘要:
A method for manufacturing animal chew toy includes providing layers of rubber material, such as tire rubber, which are cut into a general shape of an animal chew toy. A floss material comprised of a synthetic fiber mesh fabric, is also cut into the general shape of the animal chew toy and placed between the first and second layers of rubber material. These layers are molded under pressure and heat into the animal chew toy which is durable and serves to floss the teeth and gums of the animal when chewed. Ropes, animal treats, or buoyant inserts can be associated with the animal chew toy as desired.
摘要:
An object of the present invention is to provide a bladder which is unlikely to have a shapal variation along the inner wall surface of the tire and can satisfactorily extend along the inner wall surface of the tire. An inventive bladder is used to press the inner wall surface of the tire by a pressurized heating medium during the vulcanization of a green tire and is comprised of a fabric layer (purl stitched fabric layer 12) and rubber layers (silicone rubber layers 11, 13) placed one over another. Elongation rates of the fabric layer in warp direction and in weft direction both exceed 15% and satisfy: 0.4nullelongation rate in weft direction/elongation rate in warp directionnull6.0. Since the fabric layer has good extensibility, it can elongate with the rubber layers.
摘要:
In a process for manufacturing, moulding and curing tires for vehicle wheels without a vulcanization bladder, many drawbacks can result from a direct contact between the green tire and the fluid under pressure admitted in order to create the necessary pressing of the elastomer material against the vulcanization mould walls. In accordance with the present invention, said drawbacks are avoided by including in the tire manufacturing process a step of treating the inner surface of the green tire in order to prevent the permeation of the fluid under pressure into the inside of the tire structure. Said treatment can be carried out by associating at least one layer of prevulcanized elastomer material with the inner surface of the green tire.
摘要:
A system for curing a green tire made from elastomeric material includes a tire mold with a surface defining a cavity for shaping the tire. A plurality of vent passages communicate the cavity with the exterior of the tire mold. An inflatable bladder presses the tire against the surface defining the cavity for a predetermined time in response to fluid pressurization. A fluid pressure source pressurizes the bladder. A conduit communicates the fluid pressure source with the bladder. A restrictor member is located in the conduit for restricting the rate of increase of fluid pressure in the bladder to a predetermined rate of increase during the first one-third of the predetermined time. During the first one-third of the predetermined cure time, portions of the tire adjacent the plurality of vent passages cure and restrict the flow of other uncured portions of elastomeric material into the vent passages.
摘要:
The heat-sink capacity of a well-insulated dome curing press lends itself to saving external steam (flowed over the exterior of a mold in the press) when curing an article. Despite shutting off the external steam at about the half-way point in the normal heating cycle, or sooner, the temperature swing at a point 2 inches within the mold is less than 10.degree. F. This small swings allows the point of least cure (PLC) to receive the required number of cure equivalents long after the external steam supply is shut off, that is, while the press is "coasting". In the mean while, the internal heating and cooling cycle of the press may also be shortened for maximum energy savings, or left unchanged. Though the external steam is shut off before the PLC has received the required or specified number of cure equivalents at the PLC, the press-open to press-close cycle remains the same, and the quality of the cure is not measurably affected.
摘要:
The heat-sink capacity of a thick-walled article being cured with a hot liquid supplying heat to one side of the wall, allows the point of least cure (PLC) to receive a higher rate of cure equivalents even after the hot liquid is replaced with a cold liquid. In the mean while, on the other side of the wall continues to be heated. Because such a change-over is effected before the PLC has received the minimum number of cure equivalents required to effect a cure at the PLC (a "pre-cure change-over"), a valving arrangement is provided which allows the changeover to be effected without permitting a pressure drop in the bladder sufficient to permit the tire to "blow" because it is as yet uncured when the change-over is effected. Such a pre-cure change-over cannot be made when steam is replaced with water at ambient temperature.
摘要:
An open-end bladder for vulcanizing a pneumatic tire. The bladder has an annular form and a pair of opening extending through the bladder in the axial direction of the bladder. A pressure fluid is introduced into the bladder to bring it into pressure contact with the still unvulcanized tire to preshape it and to support the tire on the inside surface of the tire at the same time of the vulcanization. The bladder comprises corners extending outward from both metal-clamped end portions having the openings, first oblique portions curved and extending outward from the corners, second oblique portions extending outward from the first oblique portions, and a convex portion curved and extending outward from the second oblique portions to the maximum-diameter cross section of the bladder to couple the upper and lower halves of the bladder to each other. The thickness of the bladder is gradually decreased from the portions of the bladder, which correspond to the beads of the still unvulcanized tire, to the portion of the bladder, which corresponds to the tread of the still unvulcanized tire.