Screw drive groove type
Drive slot as cross slot with traditional cone (Phillips) to loosen or tighten the screws, tighten the tool often slip. According to the stress analysis, part of the energy is applied to the screw will make a screwdriver or screwdriver head from the screw slot sliding. The operator must be applied in order to prevent the pressure face additional slide effect.
Driver such as Hex groove with vertical sidewalls (six corners), Torx (plum type) and TorxPlus (plum enhanced), the elimination of this slide out basic differences between the effects of.Torx and TorxPlus is the former driver drive slot with an angle of 15 degrees, which is almost 0 degrees, which can ensure the best torque to the screw. Although it has a vertical side wall Torx drive slot can prevent the slide effect, but the 15 degree angle drive prevents fully engaged screwdriver head and a screw groove, and produce a little, can shorten the life of the screwdriver head radial stress.
Since the Hex drive trough not only produces stress concentration at the contact point, but also inevitably causes damage to the head of the screw, the torque is relatively low relative to the applied force
Tighten or loosen the screws in the dangerous high stress concentration. High stress mainly occurred in hex and the head of the screw screwdriver and screw stress. Based on elliptic geometry and no corner of Torx driving groove can reduce the stress concentration, can protect the screwdriver and screws and prolong its life. The ellipse based on the geometry brought little tolerance between the screwdriver head and screw and improved the force closure.
The TorxPlus drive trough further improves force closure by allowing almost 0 degrees of work angle and greater core diameter, allowing higher torque transmission and preventing damage to screws and screwdrivers
Carbide blade manufacturers often use Torx or TorxPlus to tighten the blade. Because it can effectively transfer the torque, so the use of TorxPlus is the development trend. The TorxPlus drive slot, almost do not need to exert face load can ensure the screwdriver engaged with the screw groove, reduce manual assembly operator muscle stress and fatigue. In general, the hard alloy blade manufacturers prefer manual locking mode instead of automatic locking system.