Liquid chemical grouting apparatus and valve switching arrangement in conduit system for supplying liquid chemicals to the apparatus
US4859119A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 2, 1988 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Mar 2, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D3/126
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A grouting rod is formed with a first channel, a second channel (or channels) surrounding the first channel and a third channel which is normally in communication with the first channel. A piston valve is vertically movably received in an upper portion of the third channel. When the piston valve is raised, upper lateral communication holes and upper discharge holes which are formed in the upper peripheral wall of the third channel are closed by the piston valve and concurrently the second channels are permitted to communicate with a lower portion of the third channel through lower lateral communication holes also formed in the upper peripheral wall of the third channel. When the piston valve is lowered, the upper lateral communication holes and upper discharge holes are opened and concurrently the second channel(or channels) is prevented from communicating with the lower portion of the third channel through the lower lateral communication holes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.