GOING OUT OF DATE?

NZ Truth, Issue 1184, 9 August 1928, Page 15

GOING OUT OF DATE?

The Diff. As We Know It

| HAS the day of the" differential as we know it, passed? Certainly it | | ' has very serious limitations, one being that a car with one wheel i | on slippery ground, and another on good solid surface, is helpless, be- I I cause one wheel spins. . § c.■'■ ■ . '■ 5

ANOTHER thing is that on rough •** roads a bouncing wheel gathers speed during the period it is off the ground and, on coming to earth again, spins around until it slows up to its proper rate, thus wearing out the tyre and adding to. the danger of skidding. An' absolutely new • type of differential gear has just been patented by the great French inventor, DeLavaud, who is regarded as • pi'Obably the world's • foremost authority on car transmission. The new differential relies for its action oh two roller clutches, which operate automatically, are entirely fool-proof, and practically indestructible. The action takes place m this fashion: Connected to the crown, wheel, which is driven m the ordinary way, is a large circular driven member which contains the rollers, which operate on recessed driven members connected to the axles. As the power is transmitted from the crown wheel, the rollers are drawn forward against the recessed members, and the axles are rotated. When the car turns corners, so that the outer wheel has to traverse a longer path, the drive is taken by the inside wheel, and the outer wheel overruns, the rollers automatically freeing themselves from the recesses.

When one wheel\is lifted from the ground it' does not gain speed at the expense of the other wheel, as the driving member, actuating two. sets of rollers continues, to transmit full ; power to the wheel which is running at the slower rate. ..... - This type of differential is to be exploited by a very powerful British manufacturer, so that shortly we shall see a car with it incorporated as standard. There certainly seems to, be a great future before it. Apparently' the;design was inspired by the Hurriphrey-Sand-berg free-wheel device, which operates on a very similar principle.