Electric drill
Drill is the machinery industry, construction industry and decoration industry commonly used drilling, screwdriver, screwdriver tool. Nineteenth Century Austrian Arthur James Arnot and William Blanch Brain put the motor and drill together, invented the earliest electric drill. 1889 Australian Melbourne, Wilhelm Fein invented portable electric drill. In 1917, the German Black \u0026 amp; Decker invented a drill with a pistol and a trigger. This kind of electric drill with trigger, continued to this day. Today's electric drill, most with rechargeable battery to lithium-ion battery master. Drill generally have torque control ring, the largest torque in 400 pounds or so. There are high and low speed file, when the drill with the use of high-speed gear, when the electric screwdriver screw, with low gear. The reverse gear on the drill can be used to pick up the screws. Some electric drill with LED front lights, according to the trigger, the lighting lit, lighting in front of the work point, very convenient. In addition there is a light type of straight electric drill, with 4 batteries on the 3rd. But the speed is low, the torque is small, only suitable for light live. ...