GB290314A - Improvements in rotary deep well drilling apparatus - Google Patents

Abstract

290,314. Reed, C. E. Dec. 1, 1926. Borehole apparatus.-A rotary well drill comprises a drill head 1 with recesses 2 in which rotary cutters 29 are mounted on parallel axes offset relatively to the radius of the head, further rotary cutters 6, similarly offset, being mounted on the exterior of the head. Each cutter 29 is supported on a bushing 27 mounted on a bearing member 23, the parts 29, 27, 23 being assembled and inserted into the recess 2 from below, the ends of the bearing member 23 engaging slots 25, 26 in the walls of the recess; the, bushing 27 has a projection engaging the sides of the slot 26 to prevent rotation of the bushing. Each cutter 6, together with a washer 11 with a projection 12 to engage below the drill head, is mounted on a bushing 7 which is then placed on a, boss 5 projecting from the drill head, the bushing 7 being then rotated to bring projections 8 thereon behind projections 5b on the boss: a member 14, Fig. 5, is then positioned so that segments 14a thereon fill the spaces between the projections 8 and 5<b >to hold the bushing 7 locked to the boss 5. A pin 21 is then pressed through the boss 5 and the bearing member 23 of the segment cutter 29 and is locked by a cotter 16 which also holds the member 14 in position. Openings 33 are provided to facilitate removal of the members 14. Each recess 2 has a curved upper wall, is open at its forward end fin the direction of rotation), and has a depending wall at 2<c> at tis rearward end. Passages 32 are provided for flushing liquid.