GB846844A - Improvements in pile hammer operable with either diesel or drop hammer effect - Google Patents

Abstract

846,844. Pile drivers. McKIERNANTERRY CORPORATION. Feb. 24, 1959, No. 6369/59. Class 68(2). A diesel pile driver is provided with means operated by a single hoist line for either lifting the piston within the cylinder or alternatively lifting the piston and cylinder together for use as a drop-hammer. The machine comprises a cylinder which has an upper guide part 15 and a lower working part 16, a piston 18 and a supporting framework 17. The lower end of the cylinder is closed by a concave block 19 which forms a compression ignition chamber for diesel operation. To start the diesel action the piston is raised by a hoisting block 22, running in a guide 23, by means of a catch 25 pivoted to the block and which engages under a shoulder 28 at the top of the piston. The catch is moved into and out of engagement with the ram by a trigger 33 which engages with abutments on the cylinder. The lower abutment 34 raises the trigger 33 and through the toggle links 31 and 30 swings the catch-25 under the shoulder 28. At the top of the guide cylinder the trigger engages the abutment 35 and withdraws the catch from under the shoulder 28 to release the piston. The movement of the toggle links is limited by the pins 36 and 37. If the block is hoisted beyond the position at which the piston is released it engages a stop 40 on the frame and the piston and cylinder are then raised together for use as a drophammer. In a modification a spring-loaded detent (not shown see Figs. 12 and 13) is provided to locate the toggle links in their extreme positions. In a further modification the hoisting block 22 can be locked to the guide 23 by a pin, for convenience in transport.