Abstract:
A deflector for reducing the ingestion of snow and/or other debris in one of the sprocket wheel and the idler wheel area of a vehicle equipped with endless tracks is provided. The deflector generally comprises a rigid plate associated with the vehicle and positioned near the sprocket wheel or the idler wheel thereof, and a resilient pad having an upper portion coupled with the rigid plate and a lower portion freely extending from the upper portion and extending toward the inner surface of the track to limit the ingestion of snow and/or other debris in the sprocket wheel or idler wheel area of the vehicle during its operation. The lower portion of the resilient pad is generally provided with reinforcing elements which allow the resilient pad to be essentially rigid in the direction of ingestion yet pivotable in the opposite direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present patent application is a continuation-in-part of commonly assigned U.S. patent application Ser. No. 11/142,414 Jun. 2, 2005, now abandoned and claims the benefits of priority thereof. The disclosure of U.S. patent application Ser. No. 11/142,414 is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to tracked vehicles, such as, but not limited to, construction vehicles, agricultural vehicles and military vehicles. More specifically, the present invention relates to devices and systems that deflect and generally prevent the ingestion of snow and/or other debris (e.g. ice, mud, soil, gravel, rock and the like) in the sprocket wheel or idler wheel area of such tracked vehicles during operation thereof. 
     BACKGROUND OF THE INVENTION 
     Conventionally, a tracked military vehicle comprises a set of five or six wheels on each side of the vehicle over which an endless track runs. The suspension of the wheels is independent. The system also comprises a sprocket wheel and an idler wheel, respectively disposed at each end of the vehicle and generally above the ground. The way the track engages the sprocket wheel and/or the idler wheel makes it prone for the ingestion of snow, soft soil, mud, gravel, ice or other debris. The small angle formed by the track will cause such debris to fall in, follow the track and then be ingested by the sprocket wheel or the idler wheel, especially when making small radius turn manoeuvres. For example, a conventional front drive vehicle will ingest debris in the sprocket when turning in backward motion, and ingest debris in the idler when turning in forward motion. 
     This ingestion will typically create over-tension in the track system and eventually create failures especially when an elastomeric track is used. It can also make the track touch the sponson and squeeze and/or damage certain components, or even force the track to fall off the wheels. 
     Devices and systems devised to solve this problem have been proposed in prior art patents. 
     U.S. Pat. No. 1,992,702 issued to Koop on Feb. 26, 1935, disclosed a dirt guard which is adapted to be installed in parallel to the longitudinal direction of the track. The dirt guard includes a rubber strap in contact with the inner surface of the lower run portion of the track, preferably near the lateral edge thereof. Normally, a dirt guard is installed on each side of the track. While the dirt guard generally prevents debris from falling onto the inner surface of the track, it remains that it does not prevent those debris from being ingested into the sprocket wheel or idler wheel of the vehicle if they do fall onto the inner surface of the track. 
     U.S. Pat. No. 4,763,961 issued to Parrot on Aug. 16, 1988, disclosed a debris removal apparatus which includes a hydraulically-operated pusher plate to push debris out of a track system and therefore prevent the accumulation and packing of such debris. Still, while the apparatus is suitable for the particular purpose which it addresses, it remains that the apparatus is very complex and also inefficient when not activated. Indeed, unless the pusher plate is actuated, debris can and will accumulate in the track system. 
     As seen from the foregoing, there is a need for a snow and debris deflector for a track system which is simple yet efficient. 
     OBJECTS OF THE INVENTION 
     Accordingly, an object of the present invention is to provide a snow and debris deflector for a track system that obviates or at least mitigates the above-mentioned disadvantages. 
     Another object of the present invention is to provide a snow and debris deflector for a track system which reduces the ingestion of snow and/or debris in the sprocket wheel or idler wheel area of a vehicle equipped with endless tracks. 
     Still another object of the present invention is to provide a snow and debris deflector for a track system which is simple in design and yet effective in operation. 
     A further object of the present invention is to provide a snow and debris deflector that will deflect snow and/or other debris while not causing any damage to the track. 
     Still a further object of the present invention is to provide a snow and debris deflector which can be easily repaired or replaced. 
     One more object of the present invention is to provide a snow and debris deflector for a track system which allows continuity of cleaning action. 
     Other and further objects and advantages of the present invention will be obvious upon an understanding of the illustrative embodiments about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice. 
     SUMMARY OF THE INVENTION 
     To attain these and other objects which will become more apparent as the description proceeds according to one aspect of the present invention, a snow and debris deflector for a track system is provided. 
     The main purpose of this invention is to limit the ingestion of snow and/or other debris such as, but not limited to ice, mud, gravel, soil, rock and the like (hereinafter “debris”), in the sprocket wheel or idler wheel area of the track system of a tracked vehicle. By reducing or limiting the ingestion of snow and/or debris, the deflector of the present invention significantly reduces the build up of snow and/or debris between the sprocket wheel and the track or between the idler wheel and the track. Additionally, by reducing the ingestion of snow and/or debris in the in the sprocket wheel or idler wheel areas of the track system, the deflector considerably diminishes the amount of tension created in the track and also generally prevents the track from touching the sponson of the vehicle. In turn, this generally prevents the track from falling off the wheels of the vehicle; an event generally referred to as de-tracking. 
     According to the present invention, the deflector generally comprises a generally rigid plate and a generally resilient pad mounted thereto. More particularly, the rigid plate of the deflector is generally mounted to the vehicle and positioned in a relatively close proximity to the sprocket wheel or idler wheel of the track system. The rigid plate, which generally defines a lower edge, also defines a generally inner wheel-facing side and an outer side. For its part, the resilient pad comprises an upper portion, adapted to be mounted on the outer side of the rigid plate, and a lower portion, extending freely and downwardly from the upper portion, beyond the lower edge of the rigid plate and toward the inner surface of the track. 
     In accordance with the present invention, the lower portion of the resilient pad is generally provided with one or more rigid and generally vertically extending reinforcing elements which are preferably embedded therein. The reinforcing elements generally extend in the lower portion of the pad and thus, above and under the lower edge of the rigid plate. The reinforcing elements are preferably laterally spaced apart within the resilient pad. In addition, the reinforcing elements may have different lengths; the present invention is not so limited. 
     In operation, the disposition of the reinforcing elements in the resilient pad and the mounting of the resilient pad with respect to the rigid plate will define a hinge-like portion which will allow the resilient pad to be substantially rigid in the direction of ingestion, but generally flexible or pivotable in the other direction. Hence, by being rigid in the direction of ingestion but pivotable otherwise, the deflector of the present invention will effectively deflect snow and/or debris without hindering or damaging the track or its inner surface. 
     Preferably, at least part of the rigid plate is shaped as an arc in order to follow the curvature of the outer periphery of the sprocket wheel or of the idler wheel. Preferably, the rigid plate is designed and positioned to avoid interferences with the outer periphery of the sprocket wheel or idler wheel and with the inner surface of the track. Accordingly, the rigid plate is preferably spaced from the outer periphery of the sprocket wheel or idler wheel by a distance ranging between 0.5 inch and 1.5 inch. Additionally, the lower edge of the rigid plate generally has a shape which is preferably complementary to the shape of the inner surface of the track; the present invention is however not so limited. 
     Preferably, the resilient pad is made from molded composite and/or elastomeric material such as, but not limited to, rubber. Other material exhibiting similar properties could also be used. Additionally, the lower portion of the resilient pad is preferably shaped to be generally complementary with the shape of the inner surface of the track. 
     Preferably, the deflector is mounted to the vehicle substantially transversely with respect to the longitudinal direction of the endless track. 
     The invention accordingly comprises the further constructions, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the nature and object of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which: 
         FIG. 1  is a fragmentary isometric side view of a snow and debris deflector according to the present invention, installed about a sprocket wheel; 
         FIG. 2  is an enlarged fragmentary isometric side view of the snow and debris deflector of  FIG. 1 ; 
         FIG. 3  is an isometric front view of a snow and debris deflector according to the present invention, uninstalled; 
         FIG. 4  is an isometric rear view of a snow and debris deflector according to the present invention, uninstalled; 
         FIG. 5  is a cross-sectional view of the resilient pad along line  5 - 5  of  FIG. 3 ; 
         FIG. 6  is a side view of a snow and debris deflector according to the present invention, the resilient pad being shown in three different positions; 
         FIG. 7  is a side view of a tracked vehicle equipped with two deflectors in accordance with the present invention, the vehicle being stopped; 
         FIG. 8  is a fragmentary and enlarged side view of the front snow and debris deflector shown in  FIG. 7  when the vehicle is stopped; 
         FIG. 9  is a side view of the vehicle of  FIG. 7 , the vehicle moving in direction F. 
         FIG. 10  is a fragmentary and enlarged side view of the front snow and debris deflector shown in  FIG. 9  when the vehicle is moving in direction F; 
         FIG. 11  is a side view of the vehicle of  FIG. 7 , the vehicle moving in direction R. 
         FIG. 12  is a fragmentary and enlarged side view of the front snow and debris deflector shown in  FIG. 11  when the vehicle is moving in direction R; 
         FIG. 13  is a side view of the track system of  FIG. 7 , the suspension of the road wheels being in compressed position; 
         FIG. 14  is a fragmentary and enlarged side view of the front snow and debris deflector shown in  FIG. 13  when the suspension system of the road wheels is in compressed position, 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A novel snow and debris deflector will be described hereinafter. Although the invention is described in terms of specific illustrative embodiments, it is to be understood that the embodiments described herein are by way of example only and that the scope of the invention is not intended to be limited thereby. 
       FIGS. 1 to 4  show a snow and debris deflector  100  for a track system that reduces the ingestion of snow and/or debris in a sprocket wheel  20  or idler wheel  30  (see  FIG. 7 ) area of a vehicle  10  equipped with tracks  50 . 
     The deflector  100  generally comprises a rigid plate  120  and a resilient pad  130 . 
     The rigid plate  120 , which can generally be shaped as an iron angle, is secured to the vehicle  10  and is positioned in a relatively close proximity to the sprocket wheel  20  or idler wheel  30  (see  FIG. 7 ). As seen in  FIGS. 3 and 4 , the rigid plate  120  defines an inner wheel-facing side  121  and an outer side  123  facing away from the wheel when the deflector is properly installed. 
     The resilient pad  130  generally comprises an upper portion  132  which is fixedly attached to the plate  120 , on the outer side  123  thereof, and a lower portion  134 , freely extending downwardly from the upper portion  132 , beyond the lower edge  122  of the rigid plate  120  and toward the inner surface  52  of the track  50 . 
     The rigid plate  120  is preferably made from steel or other similar rigid material. Also, as best shown in  FIGS. 3 ,  4  and  6 , at least a portion of the rigid plate  120  is shaped as an arc. This arcuate shape preferably follows the curvature of the outer periphery of the sprocket wheel  20  or idler wheel  30 . Preferably, the rigid plate  120  is designed to avoid any interference with the outer periphery of the sprocket wheel  20  or idler wheel  30  and also with the inner surface  52  of the track  50 . Accordingly, the rigid plate  120  is generally spaced from the sprocket wheel  20  or idler wheel  30  outer periphery by a distance ranging between around 0.5 inch (12.5 mm) and 1.5 inch (37.5 mm). Understandably, the exact distance can vary according to different wheel configurations. Additionally, the lower edge  122  of the rigid plate  120  is spaced from the inner surface  52  of the track  50  and preferably has a shape which is generally substantially complementary to the profile of the inner surface  52  of the track  50 . 
     For its part, the resilient pad  130  is preferably made from flexible elastomeric composite material such as, but not limited to, rubber. Understandably, other materials exhibiting similar properties could also be used; the present invention is not so limited. 
     Referring now to  FIGS. 3 to 6 , in accordance with the present invention, the resilient pad  130 , and more particularly the lower portion  134  thereof, is provided with at least one but preferably a plurality of vertical reinforcing elements  140  which are preferably embedded into the lower portion  134  of the resilient pad  130 . As is well understood, these reinforcing elements  140  may assume different configurations (e.g. rods, bars, members, etc.) and a variety of forms and cross-sectional profiles. Also, these reinforcing elements  140  may be made from any suitable material well known in the art; for example, steel, reinforced carbon fibers and reinforced fibreglass. Importantly, the reinforcing elements  140  vertically extend in the lower portion  134  of the resilient pad  130  in such a way that they extend both above and under the lower edge  122  of the rigid plate  120  when the resilient pad  130  is mounted thereto (best shown in  FIG. 6 ). Depending on the exact shape of the resilient pad  130 , the length of each reinforcing element  140  can vary and all the reinforcing elements  140  need not to be equal in length. Preferably, but not exclusively, these reinforcing elements  140  are laterally spaced-apart, according, or not, to a predetermined interval. 
     Referring to  FIGS. 1 to 4 , the lower portion  134  of the resilient pad  130  generally has a shape which is generally substantially complementary to the profile of the inner surface  52  of the track  50 . Understandably, the shape of the lower portion  134  of the resilient pad  130  will vary according to the exact configuration of the inner surface  52  of the track  50 . 
     As shown in  FIGS. 3 and 4  and particularly  FIG. 6 , the resilient pad  130  is mounted to the rigid plate  120  is such a way as to define a hinge portion  135  generally at the junction of the upper portion  132  and the lower portion  134 . In accordance with the present invention, the configuration of the hinge portion  135 , of the reinforcing elements  140  and of the rigid plate  120  allows the resilient pad  130  to be substantially rigid in the direction of ingestion (position II which corresponds to  FIGS. 11 and 12 ) due to the combined effects of the lower portion  134  of the resilient pad  130  which abuts on the lower edge  122  of the rigid plate  120  and of the reinforcing elements  140  which rigidify the lower portion  134  and prevent the latter from bending around the lower edge  122 , but also to be pivotable in the other direction (position III which corresponds to  FIGS. 9 and 10 ) due to the hinge portion  135  and due to the absence of physical constraints (e.g. reinforcing elements  140  and rigid plate  120 ). Hence, as depicted in  FIG. 6  and as explained below, the resilient pad  130 , and more particularly its lower portion  134 , takes the rigid position, namely position II, only when snow and/or other debris are pushed thereon in the direction of ingestion with respect to the sprocket wheel  20  or idler wheel  30 . In the opposite direction, the resilient pad  130 , and more particularly its lower portion  134 , will be free to pivot about the hinge portion  135 . 
     Referring now to  FIGS. 7 ,  9  and  11 , a tracked vehicle  10  is shown with a first deflector  100  mounted in relation with the sprocket wheel  20  and a second deflector  100 ′ mounted in relation with the idler wheel  30 . 
     In  FIGS. 7 and 8 , the vehicle  10  is stopped. In this case, since the resilient pad  130  and more particularly its lower portion  134  is not subjected to any force, except gravity, the resilient pad  130  will freely hang from the rigid plate  120  and will remain in a stable neutral position, namely position I depicted in  FIG. 6 . Notably, when the vehicle  10  is stopped, a space exists between the lower portion  134  of the resilient pad  130  and the inner surface  52  of the track  50 . Thus, the lower portion  134  of the resilient pad  130  is not contact with the inner surface  52  of the track  50  when the vehicle is stopped. 
     Referring now to  FIGS. 9 and 10 , when the vehicle  10  moves in a direction F, the track  50  moves in the opposite direction, thus from the sprocket wheel  20 , located at the fore of the vehicle  10 , toward the idler wheel  30 , located at the aft of the vehicle  10 . In this situation, with respect to the sprocket wheel  20 , the snow and/or the debris located on the inner surface  52  of the track  50  move away from the sprocket wheel  20 . In that case, as shown in  FIG. 9  and more particularly in  FIG. 10 , the lower portion  134  of the resilient pad  130  pivots about the hinge portion  135  and moves away from the rigid plate  120  as shown by the position III of  FIG. 6 , thereby allowing the snow and/or the debris (not shown) located in the sprocket wheel  20  area to move out. 
     However, referring now to  FIGS. 11 and 12 , when the vehicle  10  moves in a direction R, the track  50  moves in the opposite direction, thus from the idler wheel  30 , located at the aft of the vehicle  10 , toward the sprocket wheel  20 , located at the fore of the vehicle  10 . In this situation, with respect to the sprocket wheel  20 , the snow and/or the debris located on the inner surface  52  of the track  50  move toward the sprocket wheel  20 , thus in the direction of ingestion. In that case, as shown in  FIG. 11  and more particularly in  FIG. 12 , as snow and/or debris (not shown) come into contact with the lower portion  134  of the resilient pad  130 , the lower portion  134  is pushed on the rigid plate  120  and becomes rigid as explained above and as shown by position II in  FIG. 6 . Once in its rigid position II, the lower portion  134  of the resilient pad  130  effectively blocks and deflects at least a portion of the snow and/or of the debris which are carried on the inner surface  52  of the track  50  and generally prevents or reduces their ingestion by the sprocket wheel  20 . 
     As the skilled addressee would understand, during normal operation of the vehicle  10 , due to the general symmetry between the sprocket wheel  20  and the idler wheel  30 , when the deflector  100  is in position III as in  FIG. 9 , the deflector  100 ′ will generally be in position II, whereas when the deflector  100  is in position II as in  FIG. 11 , the deflector  100 ′ will generally be in position III. 
     Referring now to  FIGS. 13 and 14 , tracked vehicles such as vehicle  10  are often provided with road wheels  40 , each of them provided with a suspension system  45 . Accordingly, when the vehicle  10  runs over uneven terrain, the track  50  may move upwardly or downwardly as a result of the upward or downward movements of the road wheels  40 . When the track  50  moves upwardly, it can come in contact with the resilient pad  130  and more particularly with its lower portion  134 . Since the resilient pad  130  is free to bend or pivot away from the rigid plate  120  due to the hinge portion  135 , when the track  50  moves upwardly and contacts the lower portion  134  of the resilient pad  130 , the resilient pad  130  and more particularly it lower portion  134  will pivot away from the rigid plate  120 , as shown in  FIG. 13  and more particularly in  FIG. 14 , in order to temporarily accommodate the track  50  without damaging it. 
     Understandably, the rigid plate  120  must be mounted to the vehicle such that its lower edge  122  never comes in direct contact with the inner surface  52  of the track  50  whether the suspension system  45  of the road wheels  40  is extended or compressed to its maximum. 
     Notably, for the deflector  100  of the present invention to work properly, the latter must generally be installed transversely with respect to the longitudinal direction of the track  50  as best shown in  FIG. 1 . 
     Using the snow and debris deflector  100  for a track system according to the present invention allows an effective track system protection without any complex and expensive mechanisms. 
     Although the present snow and debris deflector  100  for a track system has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that the present invention is not limited to the features of the embodiments described and illustrated herein, but includes all variations and modifications within the scope and spirit of the invention as hereinafter claimed.