Hydraulic hammer
US4172411A · kind A · utility
17Cited by
6References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1977 |
| Grant date | Oct 30, 1979 |
| Priority date | — |
| Expiry date | Jun 6, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B6/00
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A hydraulic hammer wherein the reciprocal motion of a drill-striking piston is operated by means of a spool valve for switching hydraulic pressure to a double-acting cylinder depending upon the position of the piston. The hydraulic hammer further includes a self starter means which assures activation of the hammer whenever hydraulic pressure is applied to the hydraulic hammer and a means for compensating for variations in boring conditions such that energy is efficiently delivered by the drill striking piston.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.