Patent GB-735749-A (GB)
Title: Excavating apparatus
IPC: E21B7/06
Filed: 1953-08-07
Abstract: 735,749. Earth-boring apparatus. SMAELE, A. DE. Aug. 7, 1953 [Aug. 14, 1952 ; June 3, 1953], No. 21884/53. Class 85. Excavating apparatus comprises at least one motor-driven excavating tool, means for continuously removing the excavated material, members serving to displace and alter the direction of movement of the apparatus which is connected by a flexible bundle of lines and conduits to a remote control position, means for generating signals in response to variations in working conditions of the tool, and a hollow deformable fitting disposed around one of the constituent parts of the excavating apparatus and adapted upon expansion by the introduction of fluid therein to engage the internal surface of the bore hole to stop passage of liquid or gas. In the arrangement shown in Fig. 1 an excavating tool 4 is driven by a motor in a casing 3 connected to a tube 2 which is slidably mounted in a tube 1. The excavated materials are removed through a tube 8 by compressed air supplied through a conduit 9 to holes 4c in the tool head, material passing through openings 4b to the tube 8. The tube 1 carries tyres 1a, 1b and is slotted for connection of the inner tube 2 to tyres 2a, 2b. The tyres may be filled with air or liquid to form an air-tight seal with the surface of the excavated chamber. The apparatus is given a reptile-like movement by means shown in Fig. 3, comprising a portion 6a connected to the tube 2 and a cylinder 7 connected to the tube 1. Air under pressure is supplied alternately to both sides of the piston and at the same time the two sets of tyres associated respectively with tubes 1, 2 alternately are inflated and deflated. The tyres may each be made in sections, and by varying the amount of air supplied to each section the pressure of the tyres against the surrounding wall can be varied and so cause change of direction of the cutting head. Change of direction may also be effected as shown in Figs. 5 and 6. The casing 3 has pivots 13, 13<SP>1</SP> mounted in arms 14 on the tube 2 and is provided with a toothed segment 15. A casing 16 at one end has arms 16<SP>1</SP> mounted on the pivots 13, 13<SP>1</SP>, and at the other end pivotally supports a screw nut 19b engaging a screw 19c. The casing 16 is provided with a jointed framework 17a, 17b, 17c, the rod 17a having a tooth 15a which is brought into contact with a tooth on the segment 15 by electromagnetic means. The screw 19c is adapted to be driven by a motor whereby the relative position in height of the tooth 15a and the segment 15 can be adjusted. The pivot pins 13, 13<SP>1</SP> may be journalled in the body 2 in chambers to either of which fluid under pressure can be supplied so that the casing 3 can be deviated to one side or the other. The cutting head may be provided with forwardly projecting fixed cutters and with laterally-disposed cutters which are mounted on the outer ends of arms 21, Fig. 9, the inner ends being articulated to a head 31. The head is connected by a rod 32 to a screw nut 33 co-operating with a screw 34 on a shaft 35 driven by a motor. Longitudinal movement of the screw 34 is prevented but the screw nut 33 has limited sliding movement in a rotor 22 between elements 37, 38. The arrangement is such that on commencement of rotation of the motor in one direction the arms 21 spread outwards before rotating, and when the direction of the motor is reversed the arms are withdrawn, facilitating removal of the apparatus. Scoops may be provided behind the arms for collecting the excavated soil and delivering it to a hopper leading to the tube through which the soil is removed. Bellows sleeves may be provided at each end of the apparatus to assist in making it air-tight. The apparatus contains members which transmit information to apparatus at remote control positions outside the bore hole.