Some machine innovations enjoy instant success and bring great financial rewards for their inventors. Others are ahead of their time and rapidly fade from the scene through lack of promotion or the unwillingness of customers to change traditional habits. The limelight never shone on this machine, and it was never exactly a household word. Yet it has survived for almost half a century, little chang
ed from its original design, and is still hitting hard in its niche market of scoring, cutting, breaking and tamping. The Arrow Manufacturing Co. was founded in 1943, in Denver, and produced a variety of equipment for the construction industry. In 1955, the Arrow mobile hydraulic drop hammer was introduced. This versatile self-propelled vehicle carried a hydraulically driven hammer mounted in a moveable frame. The frame could be angled or moved from side to side across the width of the machine for working close to walls or other obstructions. The operator could set the machine for manual or automatic operation. In automatic mode, he could select the height of hammer drop and speed of travel to deliver blows of uniform impact at a uniform rate. The patented hydraulically powered “creeper gear” provided working speeds up to 32 feet per minute. With the hammer frame folded down, the machine could be driven from job to job at speeds up to 30 mph.
