Snowmobile ski and method

Abstract

A runner for a snowmobile ski is fabricated from flat metal plate stock and incorporates mounting features for securing the runner to the ski and a wear strip of a relatively harder material provided on and projecting from a lower surface of the runner body. A quick release mounting system is provided for attaching the runner to the ski, including quick installation and release wedge mounting systems. The thin runner blade and wear strip are of the same thickness and are joined by a brazed joint. The invention contemplates a method of fabricating the runner and a method of mounting the runner.

1 - 29 . (canceled) 
   
   
       30 . A method of fabricating a runner for mounting on a ski of a snowmobile, comprising:
 providing a flat stock plate of metal fabricated of a first metal material;   cutting a runner body in one piece from the flat plate stock;   forming mounting features as one piece with the runner body operative for mounting the runner on the ski; and   joining a wear strip to a bottom surface of the runner body formable of a second material that is relatively harder than that of the first material.   
   
   
       31 . The method of  claim 30 , including selecting a carbide material for the second material. 
   
   
       32 . The method of  claim 31  wherein the wear strip is joined to the runner body by brazing. 
   
   
       33 . The method of  claim 32  wherein the brazing process comprises the steps of inverting the runner body so that the lower surface faces upward;
 applying a fluxing agent to the lower surface;   placing a strip of brazing material over the fluxing agent, placing wear strip material on the strip of brazing material, supporting the wear strip and runner body in guide to support the wear strip and runner body in position, and then indirectly heating the wear strip, brazing material, fluxing agent and runner body to form a braze joint at the interface of the wear strip and runner body.   
   
   
       34 . The method of  claim 33  including selecting an aluminum-based material for the first metal material. 
   
   
       35 . The method set forth in  claim 30  wherein the step of cutting a runner body comprises concurrently stamping the entire runner body in said piece of flat plate stock. 
   
   
       36 . The method set forth in  claim 35  wherein said step of forming mounting features comprises stamp cutting at least one laterally extending hole in the runner body to provide wedging surfaces. 
   
   
       37 . The method set forth in  claim 36  wherein said step of stamp cutting is accomplished by concurrently stamp cutting at least two longitudinally spaced holes in said runner body. 
   
   
       38 . The method set forth in  claim 30  wherein said step of forming mounting features comprises stamp cutting mounting means in said flat stock plate of metal integral with an upper surface of said runner body concurrent with said step of cutting said runner body. 
   
   
       39 . The method set forth in  claim 38  wherein said stamp cutting step includes stamp cutting at least two mounting members in said flat stock plate integral with but projecting upwardly away from said upper surface of said runner body. 
   
   
       40 . The method set forth in  claim 35  wherein said cutting step includes cutting an elongate runner body lying in a predetermined plane and including upper and lower edges spanned by parallel side surfaces, said lower edge including said bottom surface; said step of joining including the step of brazing said wear strip to said lower edge. 
   
   
       41 . The method set forth in  claim 40  wherein said wear strip comprises a carbide rail having a lateral width substantially equal to the thickness of said runner body. 
   
   
       42 . The method set forth in  claim 40  wherein said step of cutting includes the step of concurrently forming an elongate notch in said bottom surface; and including the step of disposing said wear strip in said elongate notch prior to said joining step. 
   
   
       43 . The method set forth in  claim 42  wherein said step of forming said elongate notch includes cutting a notch having a lateral width substantially equal to the lateral width of said runner body. 
   
   
       44 . The method set forth in  claim 35  wherein said step of cutting a runner body comprises stamp cutting a blank having a pair of laterally opposed planar wings each having a truncated triangular shape with a laterally outer edge of a predetermined length, a laterally inner edge of a lesser predetermined length and longitudinally opposite end edges which laterally inwardly converge between said laterally outer and inner edges, and a central base section integral with said laterally inner edges. 
   
   
       45 . The method set forth in  claim 44  wherein said step of cutting further includes the step of forming a longitudinally extending slot in the under surface of said central base section. 
   
   
       46 . The method set forth in  claim 44  wherein said step of forming is accomplished by concurrently stamping said slot in the underside of said central base section concurrent with said cutting step. 
   
   
       47 . The method set forth in  claim 44  further including the step of laterally inwardly folding said wings relative to said central base section to generally parallel positions. 
   
   
       48 . The method set forth in  claim 47  wherein said joining step includes the step of placing said wear strip in said slot and cutting opposite ends of said wear strip so that the opposite surfaces of said wear strip converge and are flush with said longitudinally opposite end edges. 
   
   
       49 - 53 . (canceled) 
   
   
       54 . A method of manufacturing a wear bar for mounting on the underside of a ski including the steps of:
 selecting a flat plate of metal lying in a plane and having a predetermined uniform thickness;   severing the plate of metal to provide a one piece wear bar runner of uniform width including the steps of concurrently stamp cutting   an elongate thin wear bar runner having opposite ends and upper and lower edges spanning said ends and lying in said plane, and   a plurality of longitudinally spaced apart runner mounting members integrally extending from said upper edge and lying in the plane of said wear bar runner;   said step of stamp cutting including the step of concurrently cutting an elongate slot in said lower edge of said runner; and mounting an elongate carbide wear rail, having a thickness substantially equal to said uniform thickness, in said slot.   
   
   
       55 . The method set forth in  claim 54  wherein said mounting step includes the step of brazing said carbide wear rail to said runner. 
   
   
       56 - 61 . (canceled) 
   
   
       62 . A method of manufacturing a traction increasing wear bar for mounting on the underside of a ski of an ice-going vehicle, comprising:
 stamping an elongated flat runner body from a single piece of metal plate stock of generally uniform thickness having longitudinally opposite ends, an upper surface and a lower surface, and including at least a pair of mounting members projecting from said upper surface and stamped as one piece with the runner body of the same metal plate stock and being of generally the same uniform thickness as that of the runner body; and   securing a carbide wear strip to the lower surface of the runner body.   
   
   
       63 . The method of  claim 62  wherein the carbide wear strip is selected to have the same general thickness as that of the runner body. 
   
   
       64 . The method of  claim 62  wherein the runner body and carbide strip are heated to an elevated temperature and the carbide strip is secured by brazing to the runner body. 
   
   
       65 . The method of  claim 64  wherein following brazing, the assembled runner body and wear strip are quenched to harden the runner body. 
   
   
       66 . The assembly of  claim 65  wherein the quenching takes place in a bath of quenching oil. 
   
   
       67 - 71 . (canceled) 
   
   
       72 . A method of mounting a traction increasing wear bar to a ski of a snowmobile having an elongated runner body with longitudinally spaced ends, an upper edge and a lower edge and including mounting features operative to couple the wear bar to the ski, said method comprising:
 moving the wear bar into engagement with the ski, and   without tools securing the wear bar releasably to the ski.   
   
   
       73 . The method of  claim 72  wherein the securement of the wear bar includes moving the wear bar longitudinally relative to at least a portion of the ski once the wear bar is brought into engagement with the ski to lock the wear bar releasably on the ski. 
   
   
       74 . The method of  claim 73  including providing cooperative camming surfaces between the wear bar and said portion of the ski which interact to bind the wear bar frictionally to the ski in response to the relative longitudinal sliding movement. 
   
   
       75 . A method of mounting a traction increasing wear bar to a ski of a snowmobile having an elongated runner body with longitudinally spaced ends, an upper edge and a lower edge said method comprising:
 positioning the wear bar adjacent the underside of the ski,   forming mounting features, including a transverse aperture, as one piece with the runner body operative for mounting the runner on the ski; and   coupling said blade to the snowmobile ski by passing a transverse pin transverse through said aperture and a portion of the ski to concurrently wedge said blade into snug engagement with said ski.   
   
   
       76 . The method set forth in  claim 75  wherein said passing step is accomplished by sequentially transversely piloting a stepped cam bolt, having a head at one end and a thread at the opposite end of a predetermined diameter and an intermediate camming section between said ends increasing in diameter in a direction from said one end to said opposite end, thru said aperture in a direction from said one end toward said opposite end to incrementally index said upper edge toward said ski. 
   
   
       77 - 85 . (canceled)