CATERPILLAR AROUND SKI

The idea is to make motonarty, so that they could ride on soft snow, took possession of me for a long time, fifteen years ago. But to get to work in no hurry, carefully pondered, what I would like to see your snowmobile. So gradually the mind has developed a structural diagram of a propulsion device in the form of two blocks of the ski, light surrounded the track.

What prompted me to this design? Of course, years of practice skiing. Skiing in our area — indeed a necessity, without them it is difficult. Remember how in the childhood we did them ourselves, and the quality of modern factory hardly better.

 

The kinematic diagram of a snowmobile:

1 — driven crawler sprocket Z = 14,2—bearing skis carriage 3 to the leading lug sprocket Z = 10. 4, 5 — motorcycle sprocket, Z — 19, 6 — output sprocket of the engine 7 — engine “IZH-Planeta”,8 — frame, 9 — carriage.

 

So, while skiing, I noticed two things. First of all, if the ski is accidentally ingested an object — pole, smooth twig branches etc., the slide is improved. And another thing: when climbing the “ladder” even loose fresh snow keeps skiers well, not sliding down. These two observations suggested to set the skis inside the “infinite” ladder-track. This design, in my opinion, was to provide small specific pressure and good permeability even when driving on a fairly steep hill slopes.

 

The frame of the snowmobile to the structural elements of propulsion and transmission:

1 — frame (the area 35X35 mm), 2, 3 — transverse arc, 4 — longitudinal roggerone, 5 — the case intermediate shaft bearing transmission, 6 — under-motor-spar (area 35X35 mm), 7 — transverse beam for fixing the steering mechanism (channel 20 mm), 8 — area under the rocker arm to the steering mechanism 9 — Klondike solitaire mounting swivel axis, 10 — clamp rotary axis, 11 — axis turning, 12 — bracket, intermediate shaft to the transmission, 13 — holes for mounting the drive shaft caterpillar tracks 14 — Bush axis carriage 15 — skin-white bracket, 16 — support plate of the steering column, 17, 20, the corners of attachment of the engine with longitudinal slots for chain adjustment, 18 — area 19 — clip 21 is a platform 22, 23 — movable and fixed parts of the tensioner crawler belt 24 and the clamp axis carriage 25 bolts M10 26 housing bearing driven shaft of caterpillar tracks, a 27 — longitudinal beam of the carriage, 28 — reference of the ski carriage, 29, 32 — transverse beam of the carriage, 30 — the arc of the cradle 31 — axis carriage area 33 of fastening the skis to the cross beam 34 corner mount swivel skiing to the a-pillar, 35 to swivel ski.

 

And more than ten years operation of snowmobile confirmed my assumptions. Practice has shown that the concerns to reduce the use of such a scheme the overall efficiency and increase the wear due to friction was in vain. The fact that between the ski and the straps trucks Caterpillar always gets snow, and it’s a wonderful lubricant! Even better mover operates at a temperature of -10°…-20° C, then the trucks formed a thin ice crust, which glide iron-bound skis. At zero temperature the resistance is markedly increased, but this disadvantage, inherent in the serial “the blizzards” to an even greater extent.

 

 

Now about the design of the snowmobile. The frame is made of angle cross-section 35X35 mm; the front part is bent after heating in the furnace (however, dilatato not required). Mostly its elements are welded, but the individual parts are bolted М1С. Cross beam for beam steering devices, as not perceiving the main load, can be made from the hire of smaller cross-section.

 

The drive shaft of the crawler Digitales Assembly:

1 — cover, 2 – podelniki No. 205, 3 — bearing housing, 4 — shaft, 5 — sprocket Z – 10, b — motorcycle sprocket Z – 19, 7 — washer.

 

Engine power 13.5 HP with forced of okhlazhdeniem taken from a motorcycle “IZH-Planeta” of the first issue.Reversing the car is, but prizhelanii it can be done by installing an additional gear box instead of the intermediate shaft.

 

Transmission chain, motorcycle assembled from parts. The first stage from the output sprocket of the engine on the intermediate shaft, the second intermediate shaft to the drive shaft of the propeller. The gear ratio of the second stage — 1; it is required by the layout. The length of both chains is the same — for 22 link (44); the asterisk is also equal to Z = 19.

 

 

Intermediate shaft Assembly:

1 — the bearing housings. 2 — motorcycle sprocket Z = 19, 3 — shaft, 4 — puck, 5 — cover 6 — bearing No. 205.

 

The propulsion unit includes a crawler belt, two shafts with sprockets and a clip with two blocks of the ski. On the drive shaft has two sprocket Z = 10 under the chain pitch of 38 mm deducted from the combine harvester. On the main shaft sprocket is somewhat larger diameter, Z = 14. Both the shaft(as, indeed, and the third intermediate) are mounted in the bearings No. 205. Bearing housings, the drive shaft of the propeller is bolted fixedly on the frame of the M10 casing is the driven shaft on the longitudinal beam of the carriage. The chain tension is regulated by moving the axis of the carriage with a special device. The bottom bracket axle is thick-walled pipe d 25 mm (of the same kind made to the steering column). Arc carriage — welded, box-section, the ends are connected by joints with two cross beams — corners section of 30X30 mm. is fixed To the joists at the five skis. The width of each is 100 mm; the intervals between Central 24 mm between the extreme — 84 mm (for the passage of circuit track).

 

Ski carriage is homemade, made from a birch trunk Nieuwegein form. The latter is necessary since the ski is made according to conventional technology, after a few rides, wet snow can almost fully straighten. Runners ski constrained by thin steel sheet or plate. Nails is not recommended; it is better in cutting work of the sheet to provide the required number of petals. And we should not forget that romance, except the Central, should have a metal edging along the entire length .from the edge, where the circuit tracks.

 

Truck tracks:

1 — plastic level 2 — boss of ogranichili, 3 — link chain (step 38 mm), 4 — mounting chain, 5, 6, 7, 8 — skis (on the top view is not shown).

 

Track consists of two chains with a pitch of 38 mm, which through the link on the special parts of the MB bolts attached to the trucks — plastic strips section mm. 50X16 Original straps were made of wood; I drove on them for at least 10 thousand km. But it turned out that wdeploy weather and when driving on grooved roads, they behave unsatisfactory, greatly increasing the resistance. Then I made a steel mould and cast molten plastic new tracks (and can even provide a kind of picture “soles”), Since not complaining: the same mass, a new caterpillar surpasses the predecessor in every way.

 

Truckee (through one) with the outer sides of the chains have a steel boss-constraints. They are necessary for the alignment of the tracks: their rounded side slip on edged with metal side outside of the ski.

 

In General, the cart mover should be calculated so that when riding on the uneven surface of the caterpillar in any case at the top did not touch the frame of the snowmobile.