Abstract: The rotary output of the power source of an impact device is converted to reciprocation of a body, preferably having a resilient coupler, which drives a ram into impacting in an improved rotary-to-reciprocative motion converter including a crankshaft operatively interconnected to reciprocate the body. The converter includes a crankpin bearing, a flat bearing surface secured normal to the reciprocation on a connecting rod or directly on the body, and a constraint spring to hold the flat bearing surface in contact with the bearing during operation. The improved converter provides reciprocation free of angular motion of connecting rods and irregular motion within clearances between moving elements to significantly reduce extraneous harmonic vibrations and energy losses therefrom.

Abstract: An impact device incorporating an improved air spring coupler in the form of a novel cylinder-piston is disclosed, in which the air spring is linear, i.e., the air spring stiffness is substantially constant over the operating range of the air spring displacement. Selected relations between piston area, ram mass, cylinder volume and equivalent length, crank radius, frequency of impacts and power available in the impact device are disclosed for which the improvement of such linear air spring stiffness is obtained for preferred embodiments.

Abstract: An electric branch-line combiner is disclosed by which double power at double voltage is obtainable from two branch-line outlets of a typical existing branch-line circuit interconnected to a typical three-wire electric power source and by which electrical grounding means are readily, conveniently and safely obtained directly from two such existing branch outlets, each having only two contactors.

Abstract: An impact device, incorporating power drive means having a resilient drive element for generating successive ram impacts against a tool by reaction of the resilient drive element against the device frame, incorporates resilient bias means, interposed between the frame and the tool, to continuously transmit bias force from frame to tool acting to hold the tool firmly against a workpiece during operation, while resiliently suspending the frame for free dynamic motion clear of motion limiting stops, thereby eliminating spurious tool and frame motions and directing the impact energy of the ram to more efficiently and effectively accomplish impact work.

Abstract: An impact device incorporating an improved air spring coupler in the form of a novel cylinder-piston is disclosed, in which the air spring is linear, i.e., the air spring stiffness is substantially constant over the operating range of the air spring displacement. Selected relations between piston area, ram mass, cylinder volume and equivalent length, crank radius, frequency of impacts and power available in the impact device are disclosed for which the improvement of such linear air spring stiffness is obtained form preferred embodiments.

Abstract: Rotary-powered exciter-reciprocative means are disclosed by which improvements in efficiency and effectiveness of impact devices, effected by important reductions of wasteful extraneous harmonic vibrations through the use of long double connecting rods, are obtainable in selected embodiments incorporating gearing, by which a smaller lighter weight rotary motor of different rotational frequency from that of the impacting can be utilized.

Abstract: A power driven crankshaft is mounted on a frame and is connected by a pair of connecting rods to a coupler body, having guide means thereon to limit movement of the body to straight line reciprocation. Selected positioning and arrangement of crankshaft, bearings, connecting rods, journals, wrist pins, power drive means, reciprocating body guide means and selected crankarm result in high impact force being delivered to an impact tool with significantly reduced energy loss caused by oscillatory structural deflections spurious vibrations, and rotations. An improved coupler incorporates an air spring with selected central vent means resulting in nearly constant spring stiffness.

Abstract: Electric power, transmitted to a typical building by lead-in wires and distributed throughout the building by branch lines from which only a fraction of such power is available at each existing branch outlet, is re-combined in an electric branch-line combiner which incorporates two or more electric input plugs, that fit into and receive power from two or more selected branch outlets, and contactor-selector means which relate voltage polarities and phases of the interconnected branch outlets and input plugs and channel the combined power transmitted through such two or more plugs into a single combiner outlet.