GB368957A - Improvements in or relating to rotary earth boring tools - Google Patents

Abstract

368,957. Hydraulic turbines. LEMBCKE, H., 7, Hedwigstrasse, and SCHMIDT, P., 10, Arcostrasse, both in Munich, Germany. Feb. 23, 1931, No. 5648. Convention date, Feb. 24, 1930. [Class 110 (iii).] An earth boring drill is driven directly by a slow - running hydraulic turbine in which the driving fluid moves at high speed compared with the circumferential speed of the turbine blades and passes through a number of guide and rotor wheels. In Fig. 1, the turbine 2 is slidably connected to the fluid supply pipe 1 by a pipe 4 and comprises a rotor with a number of rings of external blades 7 supported on upper and lower bearings 13, 17, which are continuously flushed by the driving fluid ; the fluid leaving the turbine passes through ports 11, 12 to the drill to remove sludge. The fluid acts on an apertured wall 18 in the rotor to apply pressure to the drill ; the aperture may be conical, and a spring-pressed valve 27, Fig. 4, controlled by a centrifugal member 33 to adjust the pressure on the drill. Means may be provided to byepass the driving fluid through the rotor so as to direct it in a jet on the bottom of the hole to release a stuck drill. In Fig. 2, within the rotor are reverse blades 19, cooperating with guides 21 on a stationary rod 23 ; a valve 25, operated by rods 26, directs the fluid either outside or inside the rotor whereby the drive is reversible. Alternatively, separate main and reverse turbines may be provided one above the other. The Specification as open to inspection under Sect. 91 (3) (a) states also that lifting of the liquid supply or discharge pipe may act through cams &c. to cut off the supply to the turbine ; this subject-matter does not appear in the Specification as accepted.