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 Self-Blocked Differential

A cam differential is one of differentials of the raised friction . Such differentials by transfer torque to drive wheels increase it on a lagging behind wheel in comparison with running (skidding).

Next diagram illustrates the principle of work  of the cam differential (pict. 1). There you can see two racks (2, 3) with the rounded cams, the carrier of the differential (1) in which apertures settle down blocks (5). The drive link is a carrier. It's force is transferred to blocks (5). The blocks leaning  with undercuts on rack cams (2, 3), push them in a direction of moving of the carrier. At identical speeds of racks all elements move with such speed, and blocks in the carrier apertures are not moved. Let’s consider a case when the speed of the one rack (for example 2) becomes higher. In this case it's cam, with block leaned on, “runs away” forward. Upper rack pushes the block downwards by cam. The speed  of this rack will be less than the speed of the carrier. But for moving the block, needs to overcome the friction in pairs – “carrier aperture-block” and “block-cam of the upper rack”. So, the force, transferring from the carrier to lagging rack, will be higher than the force, transferring to rack moving with higher speed.

That from considered circuit to get a real construction, it is enough to “curtail” in a ring both racks and carrier. Such construction is on the second picture. Numbered details are the same as on the previous scheme. The carrier (1) is combined with the body of differential and differential ring gear. The internal star (2) with blocks transfers a moment to the left axle through the slit connection. The external star (3) – to the right board of the automobile. Submitted construction provides the increasing of the moment in 4-5 times on the lagging wheel in comparison with skidding. And so, the passableness of 4WD car is increasing in a rank, without  changes, in 4WD car control.


     Price for self-blocked differential is 800 USD without delivering. We have a special price for Club members .

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