The present invention relates to method and apparatus for tread de-molding and, more particularly, to a method and apparatus for removing a tread element such as e.g., a tread belt from a mold.
Retreaded tires are commercially available and provide an economical option to obtaining additional use of a tire after the tread has worn. The conventional process of retreading generally includes application of a length of tire tread, referred to herein as a tread band, to a tire casing from which the original tread band or a retread band has been removed. Prior to such application, the new tread band is manufactured by a process that includes providing tread features or tread sculpture to the tread band by means of a tread press operation.
Conventionally, the tread press is loaded by using a machine to drag the uncured tread element, e.g., a tread band, across the longitudinal length of the tread press until the tread is located in the proper position. The tread press generally includes an upper mold portion and a lower mold portion with features for creating the tread being located on the lower portion. Once the tread is properly located, the press is closed by forcing the upper and lower mold portions together to mold the tread i.e., create tread features into the tread band.
After molding, the tread band must be removed from the mold. Depending upon the intended tire size the tread band can be heavy and somewhat cumbersome. For some tread patterns, forces must be applied to pull the tread band out of the mold in addition to lifting and moving the tread band. Accordingly, removal of the tread band from a position between the mold elements is manually intensive. Additional challenges are presented when the press is equipped with multiple levels along the vertical direction whereby several treads may be molded at the same time.
Accordingly, an apparatus and method that assists in the removal of a tread element from a mold would be useful. An apparatus and method that can be readily placed between upper and lower mold portions for removal and/or transport of a tread element would also be useful. Such a device or method that can be, in certain embodiments, adjusted for different mold heights and/or introduced from either longitudinal end of the mold would also be useful.
Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one exemplary embodiment of the present invention, an apparatus for removing tread from a mold element is provided. The apparatus includes a conveyor for receipt of the tread. The conveyor defines a longitudinal direction and is movable along the longitudinal direction. The conveyor is connected to a fixed pathway and is configured for sliding in the longitudinal direction along the fixed pathway. A de-molding head is attached to one end of the conveyor and moves with the conveyor. The de-molding head includes at least on drive roller is configured for capturing the tread and advancing the tread over the conveyor.
Variations of this embodiment provide still other exemplary embodiments of the present invention. For example, the fixed pathway may be constructed from a first pair of rails located along the sides of the mold element whereby the conveyor can be suspended over the mold element. The fixed pathway may include a second pair of rails aligned longitudinally with the first pair of rails whereby the conveyor can be positioned adjacent to the mold element. The fixed pathway may also include a third set of rails attached to the second set of rails and foldable with respect to the second set of rails. As such, the third set of rails is configured for connecting the first and the second sets of rails. A movable platform can be provided for supporting the second pair of rails. The platform may be height adjustable relative to the mold element whereby the height of the second pair of rails may be selectively determined.
The conveyor can be constructed as a plurality of rollers that are positioned in adjacent fashion along the longitudinal direction of the conveyor. A plurality of casters can be mounted to the conveyor and positioned between the conveyor and the fixed pathway to facilitate the sliding of the conveyor relative to the fixed pathway.
The de-molding head may include a pair of drive rollers attached to one end of the conveyor and movable with the conveyor. The drive rollers may be selectively movable towards each other whereby the tread may be captured between the two rollers and advanced over the conveyor. A power source may be provided that is connected to at least one of the drive rollers by a drive shaft whereby the power source may be used to rotate the drive rollers to pull the tread onto the conveyor. A pivot arm may be attached to at least one of the drive rollers. At least one actuator can be attached to the pivot arm whereby the pivot arm can be selectively positioned so as to move at least one drive roller towards or away from the other drive roller.
In another exemplary aspect of the present invention, a method for removing tread from a mold element is provided. The method includes the steps of positioning a conveyor proximate to the mold element, pressing a portion of the tread element at a location adjacent to the conveyor, pulling the tread onto the conveyor while simultaneously sliding the conveyor along the longitudinal direction of the conveyor. The tread may be moved onto the conveyor along its longitudinal direction. The positioning step may include positioning the conveyor at a location over the tread and the mold element. The sliding step may include removing the conveyor from its position over the tread and the mold element during the pulling step. This exemplary method may also include adjusting the height of the conveyor relative to the tread.
In certain applications, this exemplary method may include a step of folding the tread over itself during the pulling and sliding steps. Alternatively, or in addition thereto, this method may include turning the tread over during the sliding step. This method may also include positioning the tread between two drive rollers that are moved towards each other. As such, the drive rollers may be rotated to move the tread onto the conveyor during the pulling step.
In still another exemplary embodiment, the present invention provides an apparatus for extracting tread from a mold element. This embodiment includes a fixed pathway for delivering the apparatus into a predetermined position relative to the mold element. A de-molding head is configured for movement along the fixed pathway. The de-molding head includes at least one drive roller that is configured for capturing the tread and pulling the tread towards the de-molding head while the de-molding head moves along the fixed pathway.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
The present invention relates to method and apparatus for tread de-molding and, more particularly, to a method and apparatus for removing a tread element such as e.g., a tread belt from a mold. For purposes of describing the invention, reference now will be made in detail to embodiments and methods of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Apparatus 100 includes a conveyor 105 that is constructed from a plurality of rollers 110 placed adjacent to one another along the longitudinal direction L of conveyor 105. Rollers 110 are freely rotatable and allow tread belt 10 to move readily along conveyor 105 as described below. Although rollers 110 are shown as cylinders in
Conveyor 105 is mounted upon a table or platform 130. For this exemplary embodiment, platform 130 includes wheels 135 that allow an operator to position platform 130 as desired relative to mold press 20 for removal of tread belt 10. Once tread belt 10 has been withdrawn from lower mold portion 15, platform 130 can be used to transport tread belt 10 to the next step in the manufacturing process. Although not shown, platform 130 can be constructed with height adjustment features such that the height of conveyor 105 may be adjusted relative to mold press 20. Alternatively, the height of the mold press 20 or the mold portion 15 could be adjusted to the appropriate height of platform 130 so that conveyor 105 can slide therebetween. Such features would be particularly useful when used with a mold press having multiple molding layers or e.g., multiple molds that are vertically stacked.
As part of the fixed pathway, another pair of rails 140 is positioned along the sides of lower mold portion 15 and are attached to mold press 20. Rails 140 extend the length of lower mold portion 15 and are provided to support conveyor 105 in a position above lower mold portion 15 as shown in
Once conveyor 105 has been positioned over lower mold portion 15 as shown in
Turning now to
Once tread belt 10 has been clamped between drive rollers 155 and 160, tread belt 10 can be advanced onto conveyor 105 by causing drive rollers 155 and 160 to rotate. A power source (not shown) is connected to de-molding head 150 by a drive shaft 190. Rotation of drive shaft 190 causes drive gear 195 to rotate in the direction of arrow W, which in turn rotates drive shaft 160 in direction of arrow X. Chain 200 connects drive gear 195 to idler gear 205, which is mechanical communication with drive roller 155 by way of chain 210 (
For convenience, the power source connected to drive shaft 190 may be a portable power tool such as e.g., an electric drill. In addition, shaft 190 may be configured for connection to an electric drill on one end and releasably attached to apparatus 100 on the other. For example, shaft 190 may terminate in a pair of pins that are received into apertures of another shaft or gear on apparatus 100. In such case, an operator could power apparatus 100 by inserting the two pins into connection and then powering the drill. In this way, if the connection is broken, the operation of apparatus 100 is terminated.
Accordingly, in operation, the apparatus 100 including conveyor 105 is placed into position proximate to mold press 20 as shown in
Referring to
Rotating drive shaft 190 in the direction of arrow W (
For the exemplary embodiment described above, the fixed pathway has been described as a rail assembly that includes rails 125, 140, and 145. However, using the teachings disclosed herein, one of ordinary skill in the art will understand that other constructions may be used to provide the fixed pathway. By way of example, grooves with an upper restraining device could be used in place of the rails to provide a path for movement of the conveyor.
Using the teachings disclosed herein, it will be understood that other methods and embodiments may be used within the scope of the present invention and claims that follow. For example, apparatus 100 can also be used to remove tread belt 10 from the lower mold portion 15 without first positioning conveyor 105 over tread belt 10. More particularly, referring back to
Apparatus 100 can be used to remove tread from an upper mold portion as well. In such case, the starting position for apparatus 100 could be directly under the upper mold portion containing tread belt 10, followed by a process in which tread belt 10 is folded back onto the conveyor. Alternatively, in a manner similar to that of the previous paragraph, the starting position for apparatus 100 could be at a location that is adjacent to—but not below—the upper mold portion, followed by a process in which tread belt 10 is pulled onto conveyor 105.
For certain applications, the use of conveyor 105 may be unnecessary. For example, it may be desirable to use an embodiment of the present invention to pull the tread from the mold without delivering the tread onto a conveyor. In such case, the present invention includes exemplary embodiments where apparatus 100 is equipped without conveyor 105 but with a de-molding head 150 that can be used to extract the tread from the mold.
While the present subject matter has been described in detail with respect to specific exemplary embodiments and methods thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art using the teachings disclosed herein.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2009/055493 | 8/31/2009 | WO | 00 | 2/9/2012 |