The present invention relates generally to tire chains, also known as snow chains and, more particularly, to a tire chain assembly for use with dual-wheeled vehicles and a method of installing same.
Tire chains are applied to the drive wheels of a vehicle to provide greater traction on roads covered with snow or ice. Most tire chains comprise two circular outer chains, one on each side of the tire, connected by a plurality of evenly spaced cross chains that extend across the tire tread.
The tire chains are normally installed by laying the chains on the ground in front or behind of the vehicle's drive wheels and then driving the vehicle onto the chains. The chains are then wrapped around the tires and the side chains are fastened together by a suitable connector. Some types of chains for large commercial vehicles also include a plurality of cam-like tensioners in the side chains which are used to tighten the side chains and thereby cause the cross chains to tightly grip the tire tread.
Conventional tire chains suffer from a number of disadvantages. If the side chain connectors and/or tensioners are not properly tightened or if they loosen as the vehicle is driven, the chains may become detached from the wheel or the wheel may spin within the chain and cause the vehicle to lose traction. Installation of the tire chains is also time-consuming because the installer must first exit the vehicle to position the chains on the ground, then reenter the vehicle and drive it onto the chains, and then exit the vehicle again to complete the installation by wrapping the chains around the wheels, attaching the side chain connectors, and maneuvering the tensioners to tighten the side chains. In situations where a vehicle is stuck in snow, it can be difficult or impossible to apply these types of conventional tire chains because the vehicle cannot be driven onto the chains. Installation of the tire chains also normally requires that the installer lay on the ground, which is normally covered in snow or slush, to reach the back side of the wheel to fasten the inner side chain connector and maneuver the tensioners. Because the tire chains must often be applied while the vehicle is parked on the shoulder of the road, the vehicle and the installer are exposed to other traffic traveling along the road. Removal of these types of tire chains is also time-consuming because the individual must first disconnect the chains, return to the vehicle to drive it off of the chains, and then leave the vehicle to pick up the chains from the ground.
These installation and removal difficulties and hazards are further magnified when the vehicle is a commercial vehicle that has double or dual drive wheels, each of which may need to be chained. Such vehicles may frequently encounter primary roads which have been cleared of snow or ice and secondary roads which are remain covered in snow or ice. Similarly, vehicles traveling through mountainous areas may frequently encounter stretches of road covered in snow or ice and other stretches of road that are dry. Because the tires and chains can be subject to excessive wear when the vehicle is driven on dry roads, the driver may need to frequently stop to remove or reapply the tire chains as different road conditions are encountered. Because of these difficulties and hazards in installing and removing conventional tire chains, many drivers of commercial vehicles prefer to simply park the vehicle and wait for better road conditions or, worse, drive their vehicles without installing the tire chains.
A need has thus developed for tire chains that can be used with vehicles having dual wheels and which overcome the above-described disadvantages of conventional tire chains.
In one aspect, the present invention is directed to a tire chain assembly for use on a vehicle having dual wheels which mount tires having tread surfaces. The tire chain assembly includes a generally planar circular disk. The disk includes a first series of concentrically arrayed holes through which a set of wheel lugs may extend to permit mounting of the disk between an inner and an outer wheel in the pair of dual wheels. The disk further includes a second series of holes arrayed about an outer periphery of said disk. In one embodiment, the second series of holes each comprises a key slot having an enlarged portion and a narrower portion that extends radially outward from said enlarged portion. The tire chain assembly further includes a tire chain which has an outer ring element, a number of cross chains each connected at one end to the outer ring element, and a disk connector at an opposite end of each of said cross chains for interconnecting with one of the second series of holes to releaseably attach the cross chain to said disk. When the disk connectors are attached to the disk, the cross chains extend across the tread surfaces of the tires. A tensioner is positioned in the outer ring element to tighten the cross chains against the tread surfaces of said tires when the disk connectors are interconnected with the second series of holes in said disk. In one embodiment, the outer ring element is a length of chain.
The disk connectors each have a body portion, a pin protruding from the body portion and having a neck portion and an enlarged head positioned at an end of the neck portion, and a locking element carried by the body portion. The neck portion of said pin is sized to move along the narrower portion of the key slot and the enlarged head is sized to insert through the enlarged portion of the key slot and not pass through the narrower portion of the key slot to prevent detachment of the pin from the key slot when the neck portion is positioned in the narrower portion of the key slot. The locking element is moveable between a locked position preventing removal of the pin from said key slot and a released position allowing removal of the pin from the key slot.
In another aspect, the present invention is directed to a method of installing a tire chain to a generally planar circular disk mounted between the inner and outer wheels in a pair of dual wheels. The method comprises the steps of attaching a series of cross chains to the disk by releaseably attaching a disk connector at one end of each of the cross chains to the disk. The cross chains are connected at an opposite end to an outer ring element, such as a chain. After attachment of the disk connectors to the disk, the cross chains extend across the tread surface of the tires at spaced apart intervals.
In the accompanying drawings which form part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:
Turning now to the drawings in greater detail and initially to
Turning additionally to
Each disk 32 has a center opening 36 sized for mounting on the wheel hub 14 and a first series of holes 38 sized and concentrically arrayed for allowing the lug bolts 22 to be inserted through the holes 38. In order to accommodate different patterns of lug bolts 22, more holes 38 may be provided than are actually used with some of the holes 38 arranged for one pattern of lug bolts 22 and other holes 38 arranged for another patent of lug bolts 22. A second series of holes 40 is positioned near an outer periphery of the disk 32 for attachment of the chain assembly 30 in a manner to be subsequently described. In the illustrated embodiment, the holes 40 are each fashioned as a key slot 42 having an enlarged portion 44 and a narrower portion 46 that extends radially outward from the enlarged portion 44. The number of holes 40 used in the disk 32 can vary from the number illustrated in the drawings.
Each disk 32 also includes a third series of concentrically arrayed holes 48 that allow the valve stem 50 from the tire 26 on the inner wheel 18 to extend through the disk 32 for more convenient access. A plurality of the holes 48 are normally used to ensure that the disk 32 can be mounted so that the valve stem 50 is aligned with at least one of the holes 48. It is to be understood, however, that the number of holes 48 can be varied from that illustrated in the drawings and, in some instances, a single hole 48 may be used.
The disks 32 are formed from a suitably rigid material, including steel and other metals and their alloys. The steel or other metal may be treated to reduce corrosion, including by applying a coating to the metal by powder coating, electroplating, or other techniques.
The disk 32 is initially mounted with the dual wheels 16 by removing the lug bolts 22 and the outer wheel 20, inserting the disk 32 onto the lug bolts 22, and then reinstalling the outer wheel 20 so that the disk 32 is tightly sandwiched between the inner and outer wheels 18 and 20. The disk 32 can then remain permanently mounted or it can be removed at the end of each winter season.
The tire chain 34 that releaseably attaches to the disk 32 comprises an outer ring element 52 and a plurality of cross chains 54 that are connected at one end to the outer ring element 52 and at an opposite end to a disk connector 56. The outer ring element 52 is normally a length of chain, but it could be in other forms such as a metal cable or a series of interconnected metal cables.
The outer ring element 52 includes a tensioner 58 that interconnects opposite ends of the outer ring element 52 and can be maneuvered to tighten the outer ring element 52. In the illustrated embodiment, the tensioner 58 is a lever arm that is connected to an end link at one end of the chain and is inserted through a link at or near the opposite end of the chain. The lever arm is then pivoted to draw the end links closer together and is secured in place by an extra link 60 carried on the chain. Any resulting loose links at the end of the chain are secured to the tensioned chain by a carabiner 62 or other connection device.
One end of each cross chain 54 is secured to the outer ring element 52 by a suitable coupler 64 and the opposite end of each cross chain 54 is connected to the disk connector 56 by another coupler 64. The couplers 64 are preferably link-type couplers that allow relative movement between the cross chain 54 and the couplers 64.
The number of cross chains 54 is normally selected based on local regulations governing the use of tire chains and/or local road conditions. In one embodiment, five cross chains 54 are used for each drive wheel. In another embodiment, nine cross chains 54 are used for each drive wheel. More or fewer cross chains 54 can be used in other embodiments. It is to be understood that the number of cross chains 54 need not be the same for each drive wheel. For example, the tire chains 32 on the inner wheels 18 may have a fewer number of cross chains 54 than the tire chains 32 on the outer wheels 20. As but one example, five cross chains 54 may be used for the inner wheels 18 and nine cross chains may be used for the outer wheels 20. The cross chains 54 are normally uniformly spaced apart.
The cross chains 54 are normally formed from twisted links that allow better contact between the cross chains 54 and the tread surface 28 of the tire. Alternatively, other types of links may be used. The cross chains 54 are preferably formed of case hardened metal, but other types of suitably strong and durable materials may be used.
Turning more specifically to
To prevent inadvertent detachment of the disk connector 56 from the disk 32, a locking element 74 is carried by the disk connector 56. The locking element 74 comprises a cylindrical or other shaped lug 76 that extends through a hole 78 in the body element 66. The lug 76 is spaced from the pin 68 by a distance slightly greater than the distance from the radially outer end of the key slot 42 to the peripheral edge of the disk 32. The lug 76 is biased by a leaf spring 80 toward a locking position with the lug 76 extending beyond the surface of the body element 66. The leaf spring is secured to the body element 66 by a rivet 82 or other fastener. The lug 76 can be manually depressed into the hole 78 and moved toward a released position in which the lug 76 is recessed within the 78, as shown in
A slight bend may be formed in the body element 66 of the disk connector 56 to facilitate positioning of the disk connector 56 between the tires 26 during the process of attaching the disk connector 56 to the disk 32 or removing it therefrom. The disk connector 56 is formed from steel or other metals or metal alloys and may be coated, such as by cadmium or zinc electroplating, to resist corrosion.
One of the tire chains 32 is mounted to either the inner wheel 18 or the outer wheel 20 in each pair of dual wheels 16, as shown in
During installation of the tire chain 34 on one of the wheels 18 or 20, the centrally positioned cross chain 54 is normally attached on the back side of the disk 32 by inserting the pin 68 on the associated disk connector 56 into the key slot 42 at generally the 12 o'clock position on the disk 32. The disk connector 56 is then moved in a radially outward direction along the surface of the disk 32 until the locking element 74 snaps into place as a result of the biasing action of the leaf spring 80. The outer ring element 52 is then positioned on the side of the wheel 18 or 20 opposite from the disk 32. The remaining cross chains 54 are then sequentially attached to the disk 32 in a similar manner at equally spaced intervals about the periphery of the disk 32. The order of attachment of the cross chains 54 can be varied depending on the preferences of the installer. Once all of the cross chains 54 have been attached, the tensioner 58 which is generally located at the 6 o'clock position is then maneuvered to place the outer ring element 52 in tension, thereby causing the cross chains 54 to tighten across the tread surface 28 of the tire 26. The tensioner 58 is then locked in place by the extra link 60 and the loose links at the end of the chain are secured to the tensioned chain by the carabiner 62.
If tire chains 34 are to be installed on both wheels 18 and 20 in the pair of dual wheels 16, as shown in
Removal of the tire chains 34 can be readily accomplished by simply releasing the tensioner 58 to create slack in the cross chains 54 and then removing the disk connectors 54 from the disk 32 by depressing the locking elements 74 and moving the disk connectors 54 in a radially inward direction to release the pin 68 from the associated key slot 42, as illustrated in
Because the disk 32 is driven with the dual wheels 16, it can be seen that attachment of the tire chains 34 to the disk 32 prevents the wheels 16 from slipping within the tire chains 34, a problem which can occur with conventional tire chains. The tire chains 34 can be installed or removed while the vehicle 10 is stationary, thus the tire chains 34 can be applied even when the vehicle has already become stuck in the snow. Importantly, the tire chains 34 can be quickly and easily installed and removed, thereby increasing the likelihood that a driver will actually use the tire chains 34 rather than simply parking the vehicle 10 or driving in an unsafe manner without the tire chains 34.
From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objectives hereinabove set forth together with other advantages which are inherent to the structure.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and within the scope of the invention.
Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.
Priority benefits under 35 U.S.C. §119(e) are claimed in this application from provisional application Ser. No. 60/979,977, filed on Oct. 15, 2007, the entirety of the disclosure of which is hereby specifically incorporated herein by this reference thereto.
Number | Date | Country | |
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60979977 | Oct 2007 | US |