GB510890A - Improvements in mechanically propelled hammers - Google Patents

Abstract

510,890. Power hammers. HYDRAULIK GES. Feb. 9, 1938, No. 4101. Convention date, Feb. 10, 1937. [Class 83 (iv)] A hammer with oppositely moving heads hydraulically operated comprises a hammer unit A, water displacing apparatus B controlling means C, an accumulator D, pump E and tank F. The liquid medium employed is at a high pressure for example 100 to 200 atmospheres in lieu of the pressures for example of 10 atmospheres under which counterstroke pneumatic or steam hammers operate. This enables much smaller rams to be employed. One head G1 of the hammer is connected to a piston 5 in a cylinder 6 and by a cable 1 to a crosshead 2 on a retracting piston 3. The other head G2 is connected by cables 7 to a pair of pistons 8 in cylinders 9. Cylinders 10, 11 are respectively connected to the cylinders 9, 6 and have corresponding pistons 12, 13 connected to a piston 15 in a cylinder 16, connected by a pipe 22 to the control unit C. Valves 19, 20 are operated by a rod 18, which in the position indicated at a maintain the valve 19 open and the valve 20 closed. In this position the water from the accumulator enters the cylinder 16 by pipes 21 and 22, forces the piston 15 upwardly and water is forced into the cylinder 9 to raise the head G2 and into the cylinder 6 to force the head G1 downwardly. If the rod is moved to the position b the valve 19 closes and the valve 20 opens, the two hammer heads being returned. In Fig. 3 is shown a hammer, in which one head is connected to a piston 1 in a cylinder 5, and by linkage 6, 7 to a crosshead 3 attached to a piston 2 in the same cylinder. Linkages 9 are pivotally anchored at 10. The crosshead 3 is connected by a cable 4 with a head G2. Modifications of this construction may be used. In a further modification, the two heads are coupled by linkage and are operated by a single piston and cylinder.