Air venting valve of vulcanising mould
AssigneeWd Racing Oy
InventorPekka Penkkimäki
Life of this patent
Estimating the term…
Abstract
An air venting valve and method for removing air from a vulcanizing mold of a vehicle tire by the aid of an air venting valve having a body functioning as an air channel and an inner part movable in a longitudinal direction. The body includes a stem and a valve disc disposed at an inner end of the stem on the side of a mold surface, the diameter of the valve disc is larger than the inner diameter of the body. A spring member is arranged in the air venting valve for forcing the inner part in a predetermined position for opening the valve when a blank is removed from the vulcanizing mold. The lower part of the inner part of the body includes an outer thread and in the lower part of the body a respective inner thread for screwing the valve stem in the body.
Claims7
A method for removing air from a vulcanizing mould of a vehicle tire during the vulcanization of the tire, which comprises:
- positioning a tire blank in the vulcanizing mould,
- causing the tire blank to expand and press against a mould surface,
- removing air between the tire blank and the mould surface by an air venting valve which is detachable from the mould, said air venting valve functioning as an air venting channel and comprising a valve stem detachably mounted within a valve body and movable within the valve body between an open and closed position and a spring member is arranged in the air venting valve for forcing the valve stem in a predetermined position relative to the valve body for opening the valve when the blank is removed from the vulcanizing mould,
- wherein the valve stem is longer than the valve body, whereby in said detachable mounting, the valve stem is provided at its end portion with an outer thread which is adapted to engage an inner thread of the valve body, so that the valve stem is installed by screwing the outer thread of the valve stem past the inner thread of the valve body, thereby limiting the opening movement of the valve stem relative to the valve body, and whereby during the moulding, the tire blank presses the valve stem to a position where the air venting channel is closed by the valve stem and when the tire blank is removed from the mould, the spring member urges the valve stem to a position where the air venting channel is open.
Dependencies are inferred from the claim text.