The Toodle is the most advanced, innovative speed increaser ever.
Except for the Toodle, all other speed increasers include the following modules: housing, bearings, shaft and tool clamping system. The design concept of a conventional speed increaser is in principle the same as any conventional spindle. The speed increasers rotate at relative high speeds, which dramatically reduce bearing performances with time. The Toodle rotates at high speeds as well, but the bearings are replaced with new with each replacement of the cutting tool. Therefore, the Toodle provides for low dynamic run-out and high surface quality always.
Normally, the speed increaser dynamic system is made of the housing internal diameter, the bearings, the shaft, the collet and the cutting tool.
Each of these elements has its own static run-out, and when accumulated the system leads to relative high dynamic run-out of the tool cutting edge. The Toodle has no shaft, no shaft cone and no collet. With the Toodle, the bearings are assembled onto the tool shank, which decrees dramatically the run-out and vibrations. Better run-out and vibration values extend the tool life and improve surface quality.
With conventional speed increasers the tapper cone, which connects the shaft and tool via the collet, loses the original geometry and concentricity due to wear, and therefore there is a reduction in spindle performance. With the Toodle, the cutting tool and bearings are the only rotating elements, and as both are constantly replaced, there is no reduction in spindle performance.
The bearings in high speed rotation applications must be lubricated with oil, not grease. In turbine driven speed increasers, the air or emulsion normally penetrate the bearings section and reduce the lubrication efficiency, thus damaging spindle performance. In the Toodle, the lubrication is the emulsion or oil mist. The emulsion increases the cooling efficiency and serves as the lubrication. The oil spray has fewer cooling abilities but same lubrication abilities.
In conventional speed increases there is no ability to implement oil spray system and they normally use grease. The grease lubrication has no cooling capabilities thus provide lower lubrication benefits.
The bearing system is very sensitive to thermal changes, pollutions and external loads.
Therefore, the bearings in high speed increasers suffer from thermal expansion and external load due to unsuitable lubrication method. The Toodle bearings are constantly replaced with new, so the performance is always perfect.
Speed increasers which include turbines operated by high pressure emulsion face the problem of residual emulsion inside the bearings. When the spindle isn’t in use, the emulsion dries and become powder between the bearings races. This powder will cause major friction between the balls and races in the bearings during the next operation. The left over emulsion inside the bearings also decrease bearings life and performances.
In the Toodle, the machine operator may use the cutting tool, remove it from the housing and place a new unit in place of the current one. The used tool, including the turbine and bearings may be used again in a later time. In case of the Toodle, the user has a direct interface to the bearings, he may clean them, wash them and lubricated them. In case that the machine operator did not treat the bearings, the emulsion will dry and become powder like in conventional speed increasers. The damage to the bearing will be similar in both cases. But, in the Toodle the damage cost to the system in negligible.
The speed increasers include the shaft, made from stainless steel. The shaft must be balanced in special balancing machine dedicated to high speed spindles. But, the balancing is never perfect. There is always residual unbalanced forces due to balancing abilities and high rotation speeds. Statistically, bigger shaft will produce higher unbalanced forces. The collet will never be perfectly concentrated to the rotating axis, which also increase the unbalanced quality of the speed increaser. The Toodle has no shaft. The only rotating parts are the cutting tool and the bearings internal races. The rotating mass in the Toodle case is the lowest when compared to any other spindle or speed increaser. Therefore, the balancing quality of the Toodle is the best. The balancing quality has direct impact upon the surface quality and spindle life time.
During cutting operations, the end mill delivers radial and axial cyclical forces. In all speed increasers, due to high rotation speeds, the bearings are relative small in order to withstand the tangential speeds. In small bearings, the radial and axial static and cyclic loads dramatically reduce their life time. During the set-up process of the metal cutting procedure, the speed increaser may experience a crash which delivers extremely high radial and axial loads to the bearing system. The bearings might overcome the crash and still rotate, but will never again provide the same performance.
With the Toodle the bearings are replaced with new each time the tool is replaced. So if a crush occurs, the operator will replace the tool and bearings with new, and experience performance of a new spindle.
The Toodle is very simple; housing + bearings + tool. Simple is low cost, simple is accurate, simple is smart, simple is beautiful.
SFI-Toodle tech team.