Internal transport truck working in guide - has articulated frame lifting roller clear of guide when desired for sideways movement

摘要

At their hinging ends (16), the arms (18,20) can be lifted and lowered, so as to raise the rollers (26) clear of the travel surface or engage them with a guide. Lifting can be by a mechanism between the first arm (18) and an actuating arm rigidly fixed to the second arm and which thrusts them apart, and typically formed by a ram, the latter pumped up by a pedal also actuating the caster wheel brakes. In one pedal position, the brakes are released and the rollers engaged. In second and third ones the brakes are on and the rollers engaged, and the brakes released and rollers lifted respectively. ADVANTAGE - Safe guidance without collisions in narrow passages and round corners, while allowing sideways movement when desired.