US Patent:
20150197961, Jul 16, 2015
Inventors:
Thomas I. Burenga - Litchfield IL, US
Tim Burenga - Litchfield IL, US
International Classification:
E04H 17/26
F16F 3/06
Abstract:
A post driver having a reverse twisted spring is disclosed which comprises a carriage, a driving ram which is movable relative to the carriage, a hydraulic cylinder assembly having a threaded hydraulic cylinder rod extending out of a first end of the hydraulic cylinder assembly, the threaded hydraulic cylinder rod capable of movement out of the hydraulic cylinder assembly and retracted back into the hydraulic cylinder assembly, the threaded hydraulic cylinder rod being connected to the driving ram, the hydraulic cylinder assembly having a second end being connected to the carriage, and a spring assembly comprising an outer spring and a reverse twisted spring within the outer spring, a first end having a screw-in plug, a threaded rod extending out of the screw-in plug in the first end with the threaded rod being connected to the driving ram, and a second end connected to the hydraulic cylinder assembly.