PHASE 4

2.2.4 DYNAMIC LOCKING PRINCIPAL

1. Unlike other types of Lockers the LOKKA has a locking and unlocking principal that is dynamic. The more power that is applied the harder it locks so it doesn't need large bias forces constantly operating on it to keep it locked, the bias spring forces are minuscule and can be easily compressed with two fingers. This results in a locker that is able to lock and unlock extremely easily even when driving on some of the most slippery of surfaces. The locking mechanism is so sensitive that a wheel can be disengaged with one finger when a wheel is jacked up off the ground.

2. LOKKA's engineering principal is based on two sets of opposing forces but simplified . . . there are two forces acting on the internal gear sets

A. - one acting to unlock the cam and axle gears by the gear tooth design and effects of the ground driven forces acting on a wheel when cornering,

B. - the other to lock the cam and axle gears due to the camming action of the cross shaft and axle gear due to a 4 dimensional spiral cut cam groove with bearing surfaces under the effects of engine power.

3. Depending on the situation the locker can either uncouple or couple the driving gears. i.e. if the differential forces acting on a wheel to turn it faster than the wheel is being driven by the diff and engine, then that side can freely disengage and hence unlock and provide differential action. (J.Makhoul, Stable and efficient Methods for Linear traction variation, Tran. On Advanced torque bias, Vol. ASSP: 25, Oct 2002. )

2.2.5 THE MOST AFFORDABLE LOCKER

LOKKA is by far the lowest cost and value for money diff lock available in the world. The cost reductions are achieved by the economy of low part numbers, reduction in materials, assembly labor, machining and an overall weight reduction in freight. In addition the unit can be fitted DIY and results in substantial savings. It is not just cheaper at the cost of performance - it out performs and has better road handling characteristics than opposition products and is more durable, reliable and stronger than other lockers.

i. VERY LOW BACKLASH

LOKKA has approximately half the backlash of some other automatic lockers and achieves this through its different design principal. In particular it does not suffer from a large amount of backlash in the driving teeth. LOKKA uses specialized low profile gear sets (small, wide teeth) which have no backlash (almost zero) when engaged means that operation is smoother - the backlash in the unit is restricted principally to the ramping and camming action that occurs between the cross shaft acting in the groove cut in the cam gear. Because the camming action is smooth and progressive rather than sharp and abrupt it results in well mannered driving characteristics.

ii. LOAD TRANSFER AND STRENGTH

LOKKA design uses a large number of very low profile teeth which collectively do all the ramping and the driving.

Engine power is transferred through the flats of all 20 teeth at the same time rather than the original standard diff which has only 2 or 4 teeth driving at a time with all the force being transmitted between two points on the curved surfaces of the pinion and side gear teeth. LOKKA has a total linear length of approx. 12 cm and surface area of around 3cm2 and hence has 2-5 times greater surface area over which to transfer the engine power. This means that LOKKA can handle substantially more power than the original differential gears and can do so without wearing out, because when driving and locked there is no longer any of the slipping and sliding that occurs when the traditional spider and side gear turn and mesh.

iii. ELIMINATION OF EXCESSIVE TYRE WEAR

If a wheel can differentiate easily and the locking and unlocking characteristics are smooth rather than harsh, then the 4WD owner will eliminate excessive tyre wear and drive train damage common when differential action is hampered or the locker does not allow easy unlocking.