Fluid operated ram
US4371042A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 31, 1979 |
| Grant date | Feb 1, 1983 |
| Priority date | — |
| Expiry date | Dec 31, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D7/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A fluid operated ram comprises a striker body guided in an upright housing between an active stroke and a return stroke and striking at the end of its active stroke an impact transmitter resting on a member to be driven into the ground by the ram. The striker body is connected by a piston rod to a working piston reciprocatedly arranged in a cylinder coaxially mounted on the upper end of the housing, so that the striker body is driven during reciprocation of the working piston. The working piston is a differential piston and divides the cylinder into a first chamber above the upper larger face of the working piston and a second chamber below the smaller annular face of the differential piston. The second chamber permanently communicates with a source of pressure fluid, while control elements, including an axially movable valve slide and a valve rod cooperating therewith, serve to alternately connect the first chamber to the source of pressure fluid or a tank in dependence on the position of the striker body in the housing. The length of the valve rod is dimensioned so that the lower end thereof engages a contact face on the working piston during the downward movement of the latter t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.