This invention relates to a removable traction device for vehicle tires, the device having traction pads for improving traction between the tires and slippery or wet surfaces.
Certain tires are usually not suitable for use in snowy road situations and it has been the practice to put chains on tires for use on snow covered surfaces. The fitting of chains is cumbersome and time consuming. An alternative is to provide specially designed snow tires which can be fitted to a vehicle for use during adverse weather conditions, but these tires need to be removed and replaced with normal tires, at least on a seasonal basis.
Other types of traction devices are also known, such as in U.S. Pat. No. 3,335,776 which describes an expandable traction device comprising a band of flexible material fitted around the tire and bonded to the tire by means of a pressure adhesive. Also a variety of plastic or fabric “sock” like covering for tires have been designed such as disclosed in U.S. Pat. No. 5,624,509 and 7,013,548. Various techniques have also attempted to attach traction devices around wheels including U.S. Pat. No. 6,308,757.
Many issues must be addressed when adding traction devices to vehicle tires, particularly, truck and automobile tires which may be driven at speeds between 30-60 miles an hour, even in adverse weather conditions. When driven at speeds approaching at least 30 miles an hour, traction products may cause undesirable sound and harsh vibration. In addition, some devices may track badly and become misaligned on vehicle tires after relatively short distances. Other products have very limited durability and provide only a short useful life. Durability issues are aggravated by harsh conditions including abrasion, friction and heat, and simply the stress of being used on a vehicle weighing between about one and three tons, or even more for commercial vehicles.
While fabric coverings or “socks” for vehicle tires have achieved some of the desired benefits, previous sock-like products have failed to offer sufficiently increased traction, particularly on icy surfaces. Accordingly, a need exists for an improved traction enhancing device for vehicle tires that can be easily installed, provides good performance and durability characteristics, and provides greater traction enhancing benefits that have heretofore been available.
To address these and other concerns, a device has been designed comprised of a fabric tire covering with an outer circumference or belt to which traction pads are attached. Traction pads may be advantageously made of flexible urethane plastic or rubber. The flexible traction pads provide for greater durability and traction than wheel sock devices made exclusively of fabric. Metal ice studs or similar devices to increase traction on ice may also be incorporated into the traction pads. The belt portion of the device can be made of fabric with traction pads bonded, stitched or otherwise attached to it, or the belt may be comprised entirely of urethane or rubber with traction pads attached or molded into the belt. The circumferential belt is advantageously provided with an inner side skirt and an outer side skirt, both of which are made of a durable fabric or fabric like material. The outer side skirt may cover the outer face of the vehicle tire completely or may leave the center of the wheel and tire assembly uncovered. The primary purpose of the inner and outer skirts is to support the outer circumferential belt and to hold it in the proper position so that the traction pads remain positioned around the circumference of the tire. The entire wheel covering itself may be split radially on its circumference for ease of installation, or it may be circumferentially continuous and installed over the tire in a sock like fashion.
In one embodiment of the invention the traction pads have traction enhancing displacement chambers as described in U.S. Pat. No. 6,308,757, however, other traction patterns such as chevrons or traction ridges may be suitably used in alternative embodiments. In a further enhancement of the device, metal spikes or snow studs formed of any ice traction enhancing hardened material may be incorporated into the flexible traction pads on the outer circumference of the device.
The present invention will be understood from the detailed description below taken in reference with the accompanying drawings that are provided by way of illustration only and thus are not limiting of the present invention and wherein:
Turning then to
The skirts 16, 18 may be manufactured from a variety of material such as 600 denier polyester or nylon fabric, neoprene or PVC coated tarp material, or other substantial woven, nonwoven and impregnated fabrics. The belt 12 may similarly be made of a variety of materials including urethane or rubber, but more preferably thick rubber coated cloth or other impregnated woven or nonwoven fabrics, 1000 denier nylon fabric or other substantial fabric-like material. The illustrated cover 10 is split radially with overlapping segment 23 so that hook fastener pad 24 at leading edge can be placed on the tire and then covered by trailing edge with hook fastener pad 25 so that hook and loop fasteners on respective pads 24, 25 secure the cover 10 on the tire. Further, securing means such as elastic straps may be affixed to eyelets 17 to pull the cover 10 against the vehicle tire. The difference in the inner diameter 20 and outer diameter 21 of the skirts 16, 18 is typically on the order of 6 to 12 inches. Thus, an exemplary size for a wheel cover according to the invention designed for use on a 265/70-16 passenger car tire might be inner diameter of 22 inches, an outer diameter of 31 inches and a width of a 8.5 inches. The overlapping section 23 is typically on the order of 3-12 inches in length depending on the exact fastening configuration.
Fastening traction pads 14 to belt 12 presents structural issues due to stresses placed upon pads 14, as well as the heat, friction and abrasion that wheel covers 10 are subjected to when driven at reasonable speeds. Accordingly, it is desirable to utilize rubber traction pads that have been abraded on their mounting surface with a cushion adhesive to affix those pads to a cured rubber coated cloth belt 12. This bonding of the pads may be further enhanced by stitching with heavy duty thread on the flanges or in the recessed portions of the pads 14.
The details of an alternative preferred traction pad 414 are illustrated in
Although the only illustrated embodiments of the wheel cover 10 are shown split radially for ease of fastening about the vehicle tire, it is also possible to manufacture wheel covers in a continuous fashion without hook and loop or other fastening devices. In such cases, it is desirable to place an elastic band or other tensioning device in the wheel cover 10, such as in inner skirt pocket 19 illustrated in
All publications, patent, and patent documents mentioned herein are incorporated by reference herein as though individually incorporated by reference. Although preferred embodiments of the present invention have been disclosed in detail herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims.
The present application claims priority to the Oct. 1, 2007 filing date of provisional patent application, U.S. Ser. No. 60/976,664 which is incorporated herein by reference.
Number | Date | Country | |
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60976664 | Oct 2007 | US |