Patent · US Expired

Pile driver

US4187917A · kind A · utility

17Cited by
15References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 30, 1977
Grant dateFeb 12, 1980
Priority date
Expiry dateNov 30, 1997

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE02D7/26
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

The driving power and driving rate of a pile driver hammer is increased without increasing the overall weight of the hammer through the use of a hydraulic spring transformer which is disposed between the ram and the pile in the housing of the hammer and presents a Q at the frequency where the mass of the ram and the stiffness of the hydraulic spring are in resonance which is less than about one.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.