Tire chain and method of modifying a tire chain

Abstract

A tire chain includes a side member. An attachment bracket is secured at a first end region to the side member. The attachment bracket is formed at a second end region with a slot and with a channel. A crosslink member has an endless link at one end. The endless link defines an opening and is located in the slot so that the opening intersects the channel. A rod extends through the channel and the opening of the endless link and is secured against removal from the channel, whereby the crosslink member is secured to the attachment bracket.

Claims

1. A method of modifying a tire chain that comprises a side member and an attachment bracket for releasably securing to the side member a cable crosslink member, the cable crosslink member including a length of flexible stranded cable and a lug secured to the length of flexible cable at one end thereof, wherein the attachment bracket has a first end region at which it is secured to the side member and also has an opposite second end region, and wherein at the second end region the attachment bracket is in the form of a C-shaped channel defined by a bend in a metal plate member and oriented parallel with the side member, and wherein the second end region defines a slot intersecting the channel, adapted to receive the end of the cable crosslink member with the lug of the cable crosslink member in the channel and with the length of flexible cable extending through the slot, to secure the cable crosslink member detachably to the attachment bracket, the method comprising: removing the cable crosslink member from the attachment bracket; providing a second crosslink member having an endless link at one end thereof, the endless link defining an opening, inserting a part of the endless link of the second crosslink member into the slot so that a part of the opening is within the channel, and a part of the second crosslink member extends through the slot and away from the attachment bracket and the side member, inserting a rod into, along, and through the channel, parallel with the side member, and through the opening of the endless link, and securing the rod against removal from the channel, whereby the second crosslink member is secured to the second end region of the attachment bracket.

2. A method according to claim 1, wherein the rod is a bolt and the step of securing the rod against removal comprises applying a nut to the bolt.

3. A method of modifying a tire chain that comprises a side member and an attachment bracket for releasably securing to the side member a cable crosslink member, the cable crosslink member including a length of flexible stranded cable and a lug secured to the length of flexible cable at one end thereof, wherein the attachment bracket has a first end region at which it is secured to the side member and also has an opposite second end region, and wherein at the second end region the attachment bracket is in the form of a channel defined by a bend in a metal plate member and oriented parallel with the side member, and wherein the second end region defines a slot intersecting the channel, adapted to receive the end of the cable crosslink member with the lug of the cable crosslink member in the channel and with the length of flexible cable extending through the slot, to secure the cable crosslink member detachably to the attachment bracket, the method comprising: removing the cable crosslink member from the attachment bracket; providing a second crosslink member having an endless link at one end thereof, the endless link defining an opening, inserting a part of the endless link of the second crosslink member into the slot so that a part of the opening is within the channel, and a part of the second crosslink member extends through the slot and away from the attachment bracket and the side member, inserting a rod into, along, and through the channel, parallel with the side member, and through the opening of the endless link, securing the rod against removal from the channel, whereby the second crosslink member is secured to the second end region of the attachment bracket, and wherein the step of securing the rod against removal includes providing an end part of the attachment bracket that is bent toward a part of the attachment bracket between the first end region and the opposite second end region thereof and thereby restricting movement of the rod from within the channel toward the first end region of the attachment bracket.

4. A method of modifying a tire chain that comprises a side member and an attachment bracket for securing to the side member a cable crosslink member, the cable crosslink member including a length of flexible stranded cable, the attachment bracket having a first end region at which it is secured to the side member and also having an opposite second end region, and wherein at the second end region the attachment bracket is in the form of a channel oriented parallel with the side member and having an open side oriented toward the first end portion, and wherein the second end portion defines a slot intersecting the channel, the slot being adapted to receive an end of the cable crosslink member with the length of flexible cable extending through the slot to secure the cable crosslink member to the attachment bracket, the method comprising: providing a replacement crosslink member having an endless link at one end thereof, the endless link defining an opening, inserting a part of the endless link of the replacement crosslink member into the slot so that a part of the opening is within the channel, inserting a rod into, along, and through the channel, parallel with the side member, and through the opening of the endless link, and providing in the second end region of the attachment bracket a part that extends from a side of the channel toward an intermediate part of the attachment bracket, between the first end region and the opposite second end region, thereby at least partially closing the channel and securing the rod against removal from the channel, thereby securing the replacement crosslink member to the second end region of the attachment bracket.

Description

BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS

(1) For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

(2) FIG. 1 is a partial plan view of a conventional tire chain,

(3) FIG. 2 is an enlarged perspective view of an attachment bracket that forms part of the conventional tire chain.

(4) FIG. 3 is an enlarged perspective view of a part of a tire chain embodying the subject matter of this patent application.

(5) FIG. 4 is a similar view of a first modification of the tire chain shown in FIG. 3.

(6) FIGS. 5 and 6 are enlarged perspective views of a second modification of the tire chain shown in FIG. 3, in different respective orientations.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(7) FIG. 3 illustrates a modification of the tire chain shown in FIGS. 1 and 2 of the drawings. The modified tire chain that is shown partially in FIG. 3 comprises an inner side member 2, a tensioning device including an outer side member 22, inner and outer attachment brackets 18 secured to the inner side member and the outer side member respectively, and multiple crosslinks 48 each having one end secured to an inner attachment bracket and an opposite end secured to an outer attachment bracket. The attachment brackets 18 are essentially the same as the attachment brackets shown in FIGS. 1 and 2. The crosslinks 48 are composed of lengths of link chain and therefore are simpler in structure than the crosslinks shown in FIGS. 1 and 2.

(8) The links 52 of the link chain are small enough that an end of a link can fit loosely in the slot portion 44 of the keyhole opening in an attachment bracket 18 and the opening 56 defined by the link then intersects the channel defined by the bracket, in the sense that there are points within the opening that are also within the channel.

(9) In order to secure two crosslinks to an attachment bracket 18 of the tire chain shown in FIG. 3, to form part of a zigzag crosslink pattern, one end link of each of the two crosslinks is inserted into the slot portions 44 of respective openings of the attachment bracket, so that the openings defined by the end links respectively intersect the channel defined by the bracket. A bolt 60 is inserted through the channel and the openings of the two end links respectively and a nut 64 is applied to the bolt. Washers 68 prevent the nut and the head of the bolt entering the channel. In this manner, the bolt is retained in position relative to the bracket and the ends of the crosslinks are captive relative to the bracket, yet with an appropriate tool, the nut can be readily removed from the bolt, allowing removal of the bolt from the channel and detachment of the crosslinks from the attachment bracket. It is preferred that the nut be a nylon lock nut, since vibration may otherwise result in the nut inadvertently becoming detached from the bolt in use.

(10) As shown in FIG. 2, in the case of the conventional attachment bracket the free end of the curved part that is formed with the keyhole opening is generally parallel with the flat part 36 of the attachment bracket. Thus, were it not for the links of the crosslinks, a bolt placed in the channel would not be positively retained in the channel. However, it will be appreciated that in the case of the tire chain shown in FIG. 3, interference between the crosslinks and the attachment bracket serves to retain the bolt in the channel.

(11) Use of link chain crosslinks instead of cable crosslinks may be advantageous because the link chain crosslinks may be more durable than the cable crosslinks, thereby requiring less frequent repair, and the link chain crosslinks may be lighter in weight than the cable crosslinks so that any necessary repair work is easier. Further, link chain crosslinks are generally considered to provide better traction than many conventional cable crosslinks.

(12) It will be appreciated that a tire chain may be initially assembled using link chain crosslinks instead of cable crosslinks by securing the crosslinks to the attachment brackets in the manner described above prior to first mounting of the tire chain to a tire. Alternatively, an existing tire chain including cable crosslinks may be retrofitted with link chain crosslinks by detaching the cable crosslinks from the attachment brackets and securing link chain crosslinks to the attachment brackets in their place.

(13) As mentioned above, the attachment bracket 18 shown in FIG. 3 is essentially the same as those shown in FIGS. 1 and 2 since they are designed to receive cable crosslinks. In a further development, shown partially in FIG. 4-6, the attachment brackets 72 are especially designed to receive link chain crosslinks 48. As shown in FIG. 4, the openings 76 in the attachment bracket 72 are uniform width slots, instead of being keyhole openings, and are inclined to the longitudinal dimension of the channel. The openings 76 may be cut before the end of the metal plate from which the bracket is formed is bent to form the channel, in which case the slots would be arcuate as seen in the plate prior to bending, or they may be cut after the end of the plate has been bent. The inclination of the slots to the longitudinal dimension of the channel ensures that the end link 80 is substantially aligned with the other links of the crosslink when the tire chain is mounted and thereby reduces or eliminates bending stress that would otherwise be applied to the end link. In addition, as shown in FIGS. 5 and 6, the curved end of the attachment bracket that is bent to define the channel that receives the bolt 60 is not parallel to the flat part of the bracket but is bent towards the flat part of the bracket in order to restrict movement of the bolt relative to the bracket.

(14) It will be appreciated that the invention is not restricted to the particular embodiment that has been described, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims, as interpreted in accordance with principles of prevailing law, including the doctrine of equivalents or any other principle that enlarges the enforceable scope of a claim beyond its literal scope. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or more than one instance, requires at least the stated number of instances of the element but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated. The word “comprise” or a derivative thereof, when used in a claim, is used in a nonexclusive sense that is not intended to exclude the presence of other elements or steps in a claimed structure or method.

(15) The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.