Patent ID: 9410382
Filing Date: 2016-08-09
CPC Classification: E21B

Claim Text:
1. A drilling carriage adapted to move along a drilling mast extending in a longitudinal direction, the drilling carriage comprising: a body structure having a first side and a second side, the first and second sides parallel to the longitudinal direction and parallel to each other, separated in a first direction perpendicular to the longitudinal direction; a first permanent magnet electric motor coupled to the body structure, and a first pinion operatively coupled to the first permanent magnet electric motor positioned to mesh with a first rack coupled to the drilling mast and extending in the longitudinal direction; a second permanent magnet electric motor coupled to the body structure, and a second pinion operatively coupled to the second permanent magnet electric motor positioned to mesh with a second rack coupled to the drilling mast and extending in the longitudinal direction; a third permanent magnet electric motor coupled to the body structure, and a third pinion operatively coupled to the third permanent magnet electric motor positioned to mesh with a third rack coupled to the drilling mast and extending in the longitudinal direction; a fourth permanent magnet electric motor coupled to the body structure, and a fourth pinion operatively coupled to the fourth permanent magnet electric motor positioned to mesh with a fourth rack coupled to the drilling mast and extending in the longitudinal direction; the first, second, third, and fourth permanent magnet electric motors arranged such that