Adjustable and disengagable earth raise borer stem
US4011019A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1976 |
| Grant date | Mar 8, 1977 |
| Priority date | — |
| Expiry date | Jan 16, 1996 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/28
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The arrangement comprises an earth raise borer stem which is formed with a tapered surface, near one terminal end thereof, for slidably engaging and forming an interference fit with a similarly tapered collar within the center of a cutterhead. The stem further has, at the lowermost end thereof, according to one embodiment, a bolted-on flange plate which has a series of rectangular cutouts formed therein. The cutouts receive lugs which are also bolted onto a lowermost surface of the cutterhead. The cooperating tapered surfaces of the collar and the stem cooperate to react thrust and torque which is impressed through the stem to the cutterhead and the cutout flange plate impresses rotary torque onto the cutterhead by means of the lugs. The arrangement provides a simple and facile arrangement for replaceably coupling a stem and cutterhead. Coupling bolts are employed to insure and retain the interference fit, and also (by means not shown) can further be employed, as jacking bolts, to facilitate disassembly of the stem from the cutterhead. The cooperating tapered surfaces include an annular channel which has a conduit opening thereonto for the supply of hydraulic fluid under pressure t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.