The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 22, 1987
Filed:
May. 22, 1986
FlowMole Corporation, Kent, WA (US);
Abstract
A technique for providing a continuous underground tunnel is disclosed herein. This technique utilizes an elongated boring device including a forward facing, off-axis high pressure fluid jet which is rotated about the elongated axis of the device while the latter is urged forward through the soil, whereby to cause the device to bore a tunnel through the soil as it moves forward. In accordance with one feature of this technique, the boring device is steered by modulating the speed and/or the direction of rotation of its off-axis fluid jet in a way which depends upon the desired direction to be taken by the boring device within the soil. In accordance with another feature of the overall technique, the pitch angle of the boring device, as defined by its elongation axis, is monitored relative to a horizontal ground plane, independent of the roll position of the device. In accordance with still another feature of the technique, the roll angle of the boring device and the position of its off-axis jet are simultaneously monitored whereby to monitor the precise rotational position of the jet relative to its roll position.