NO142228B - DRILLING EQUIPMENT AND PROCEDURE FOR AA PULL UP THE FITTING CUTTING ORGANIZATIONS - Google Patents

Description

The present invention relates to a drilling device for drilling deep holes for the extraction of petroleum or groundwater or for examining the ground by collecting geological samples.

Such drilling devices are known where a crown cutting edge

on which diamond crystals are attached, or a serrated crown cutter with super-hard teeth is directly connected to a hydraulic motor, e.g. a turbine, and formed as a whole at the end of a drill pipe to thereby be driven directly by the hydraulic motor for digging and cutting into the ground without the drill pipe rotating. There is also known a drilling device where a drill core container which has the form of an inner tube or sleeve, and which is to contain a geological sample, is introduced through a drill pipe from the base surface side of the drill pipe and can be locked at the base surface side of the drill pipe, is connected to an extraction tool which is led through the drill pipe from the surface side, and can be pulled up to the ground surface through the drill pipe, as it leaves the drill pipe in the ground surface by being detached from it.

For cutting a columnar geological sample out of the ground

the base mass must be cut into a tube to assume a columnar shape using a cylindrical crown cutter. In order to be able to take such a drill core (geological sample) out of the soil, it was common to pull the entire used drill pipe up to the ground surface. However, with increasing depths of the boreholes, longer time will be required to extract and re-insert the drill pipe. A drilling device has therefore been developed where a sleeve for collecting a drill core is inserted into the tip of a drill pipe and a drill core is formed to be inserted into the sleeve.

The sleeve for collecting the drill core can be connected to a cable that can be passed through the drill pipe, and can be pulled up to the surface as it leaves the drill pipe which is located in the ground surface, or the sleeve for collecting the drill core is fed forward using water that is fed under pressure into the drill pipe located in the ground, and can be locked at the tip of the drill pipe. One. such an arrangement is described in JP-PS 642/1969.

If the crown bit is attached directly to the end of the drill pipe,

when replacing the drill bit, when it begins to wear, it would be inappropriate for the entire drill pipe to be brought up to the surface. A drilling device has therefore also been developed where a crown bit which is attached to a bit bit is arranged to fit into the drill pipe and extends from the end of the drill pipe to drill the ground.

To lock the parts adapted to the end of the drill pipe, a pin is passed through the upper end of the sleeve to collect the drill core or to the drill bit attachment rod, and two detents rotate at one end in the form of a scissor around the pin to to extend upwards towards the surface side, projecting at their other ends under the action of a spring through an opening formed in an axial-parallel direction on an outer cylinder which is arranged to move only within certain limits in relation to and in the axial direction of the tie rod on the outer surface thereof, while being fitted in a vertical groove formed in the inner surface of the drill pipe, so that the detents can be prevented from projecting further due to the upper side surfaces of the vertical groove . To keep the latches securely locked, a rectangular pin is arranged on the diametrical surface of the outer cylinder, so that this can be moved up and down parallel to the pin which is assigned in an opening taken out in the axial direction and on the outer cylinder, so that when setting of the pin between the two detents, the detents will be interlocked and prevented from coming out of the vertical slot.

In order to detach the drill pipe and detent from each other and to pull them up to the ground surface, a hook or hook is attached to a cable, lowered through the drill pipe and connected to a spear head formed in the top part of the outer cylinder. As the wire is pulled up, the outer cylinder will be displaced and the pin held by the outer cylinder will move upwards between the two detents, and as the outer cylinder is further displaced, the detents will be drawn within the walls of the outer cylinder at the lower edge of the opening and will be detached from the vertical track.

In a conventional locking mechanism, the pin that prevents the latches from closing and the pin that holds the latches will be located on the diametrical surface of the outer cylinder, and thus only a right and a left latch can be arranged there. In the case of transmission of a torque and a thrust force from the drill pipe through the detents of a crown cutter adapted to the lower end of the tie rod, the force transmitting surfaces cannot therefore be made larger to transmit greater forces.

With the above-mentioned device, moreover, the crown cutting will not be able to byfctésout without the entire drill pipe being brought up to the surface.

With this known device, it is also often observed that the reamer cutters are closed during digging, and that the number of reamer cutters is limited to a small number based on the strength of the support structure for the reamer cutters.

In the event that one is dealing with a deep borehole, considerable time will be spent if the entire drill pipe is pulled out and re-inserted into the ground to take a geological sample of the ground. A system is therefore also practiced where a device (internal sleeve for the collection line of a drill core) which can grasp a geological sample, is introduced into a drill pipe from the bore side of the drill pipe. The device is inserted into the drill pipe and locked to it at the end of the drill so that a geological sample can enter the device - A hook or hook (overshot) connected to a cable is inserted into the drill pipe from the surface side, and the inner sleeve device for collecting the drill core is connected to the wire through the hook so that the wire can be pulled up to bring the geological sample to the surface out of the drill pipe. (See above JP-PS 642/1969.)

The present invention also relates to a drilling device where crown bits and reamer bits can be fed into a drill pipe, can be locked at the drill end of the drill pipe and can also be pulled out of the drill pipe to thereby be replaced or repaired.

If a drilling operation is to be carried out using such a drilling device, pressurized water is supplied to the parts that make up the crown bits and the reamer bits through the drill pipe, and the water is brought back to the surface along the outside of the drill pipe. The water serves to cool the frictional heat produced when the crown cutters and o<p>reamer cutters cut through the soil, and to bring to the surface the soil or sand that has been cut out by the crown cutters and reamer cutters.

When the water that is fed into the borehole from the ground surface is absorbed by the soil and the supply of water into the pipe is stopped, the drill pipe will in some cases be practically empty of water. In such a case, when the drilling is directed downwards and if the cutting member carrying the crown cutters and reamer cutters is fed into an empty drill pipe, the member will fall down through the drill pipe under the influence of gravity and collide with the locking parts arranged on the inside of the drill pipe drill end, so powerful that these will break into pieces. The organ is therefore connected to and hangs from a wire.

On the other hand, in the event that there is water in the drill pipe, this water will present such a great resistance to the cutting member that it will not fall at a desired speed through the drill pipe only under the influence of gravity and will therefore not be securely locked by the drill end of the drill pipe. The cutting device is therefore guided to the drilling end of the drill pipe by providing a sufficient speed, or by using pressurized water which counteracts the force of gravity in the case of upward drilling. When the drill pipe is filled with water inside and outside, and in the event that the cutting member has to be drawn up to the surface through the drill pipe, the water aom joins around the outside of the drill pipe, when the drill member is pulled up very quickly, will not be able to follow the lower end of the cutting member, and a vacuum will thereby be created under the cutting member. Under the influence of this vacuum, the borehole walls will be sucked in and this could lead to the accident that the borehole walls collapse. The thus produced vacuum will also expose the winding to a large counter force, and furthermore the entire weight of the water column located above the cutting member will be applied to the winding device. Consequently, a large force will be required to reel in the wire.

The speed with which the cutting device can be pulled up to the surface, i.e. the recovery speed, has therefore been very limited, and even with drilling devices that use a cable system where no replacement of the drill pipe is carried out, it has not been possible to carry out the pulling up of the cutting device with a desired high speed.

The main purpose of the present invention is therefore to provide a drilling device where the above-mentioned shortcomings are eliminated.

More particularly, the present invention seeks to provide a locking device for a drilling device where a greater number of detents capable of transmitting large working forces can be provided, where water can be assigned to flow towards the center, where the strength of the lock can be increased, and where failed settings of the ratchet can be avoided.

A further purpose of the invention is to provide a drilling device whose crown bit can be held to the drill pipe without slack, and whose drilling direction can be accurately regulated.

Thus, the invention relates to a drilling device comprising a drill pipe and a cutting device equipped with a motor device which can be inserted into a borehole through the drill pipe, and which exhibits a central drilling tool and swiveling in and out reamer bits which can be guided unobstructed through the drill pipe, as well as a locking mechanism cooperating with the drill pipe consisting of an inner cylinder which is enclosed by an outer cylinder which can be displaced axially in relation to the inner cylinder, locking hooks which, by relative displacement between the cylinders, can be swung out and in for locking in, respectively release from recesses in the inner wall of the end of the drill pipe facing the bottom of the borehole, and a spear head arranged at the upper cylindrical end for connecting an excess shooter to a pulling device which, by pulling the spear head, causes the detents to swing in and brings the cutting member to the surface.

The present invention is thus based on the drilling device known from AT-PS 242 644. With this drilling device, the locking hooks simultaneously serve as a tool carrier and the impact wedge is fixed on the outer cylinder of the working part. The device according to AT-PS 242 644 is only suitable for relatively shallow drilling, where the drill pipe is rotated and the operation of the tool is transferred via the drill pipe. The fixing of the spear head involves few connection possibilities when inserting and removing the working part, and the known device is otherwise burdened with the disadvantages indicated above for other known constructions.

The drilling device according to the invention is characterized by the fact that the detents are stored at their lower ends, above the reamers, on the inner cylinder by means of pins and can be swung out through windows in the outer cylinder, and that the spearhead is arranged to be displaceable in relation to the cutting member's two cylinders for forming additional locking devices and/or channel and valve devices for drilling fluid.

As the detents are arranged separately from the tool, local operation of the tool is made possible when the drill pipe is stationary and thereby also the drilling of deep boreholes. In addition, the invention enables a ratchet number that exceeds the number of upriggers, and a tighter interlocking with the drill pipe in terms of torque. For the coordinated control of the ratchets, independent of the pivotable tools, it serves additional mobility of the sewing head in relation to the two cylinders, at the same time that additional coupling functions can also be achieved for the input and output of the working part according to the invention.

The invention will be described in more detail below with reference to the drawing. Figs. 1-6 show different sections of a side view, partly in section, of an embodiment of the present invention, where a cutting part is fixed on the drill side of a drill pipe and water under pressure is fed into the carrier pipe during drilling, the part B - B in fig. 2 joins the part A - A in fig. 1, the part D - D on fig.3 joins the part C - C on fig. 2, the part F - F in fig. 4 joins the part E - E in fig. 3, "the part H - H in fig. 5 joins the part G - G in fig. 4 and the part J - J in fig. 6 joins the part I - I in fig. 5. Fig. 7 is a section of Fig. 3 and shows the operation of a diverter valve. Fig. 8 is the same view as in Fig. 1 and shows the position a closing mechanism part for water flow takes when the cutting part is pulled up. Fig. 9 is the same view as in Fig. 1 , and shows the position the water flow closure mechanism part assumes when the cutting part is fed to the drill side through the drill pipe. Fig. 10 is the same view as in Fig. 2, and shows a locking mechanism when the water flow closure mechanism part is in the position shown in Fig. 9 Fig. 11 is a vertical view, partially in section, of an embodiment of the locking mechanism.

Fig. 12 is a section along the line XII - XII in fig. 11.

Fig. 13a and b are drawings showing the relationship between a locking hook

and outer cylinder.

Fig. 14 is a vertical view, partially in section, showing a spear head part of a drilling device according to the present invention.

Fig. 15 is a perspective view of an overshot.

Fig. 16 is a side view, partly in section, of the overshooter shown

on fig. 15.

Fig. 17 is a section along the line XVII - XVII in fig. 16.

Fig. 18 is a diagram showing the pull-up method by. a drilling device according to the present invention. Figs 19 and 20 are drawings, partly in section, showing the connection between the overshooter and the south head. Figs. 21 and 22 show sections of a vertical section of a drilling device according to another embodiment of the present invention, and the part K - K in fig. 21 joins the part L - L in fig. 22. Fig. 23 is a perspective view of the riser anchor and pin shown in fig. 22.

Fig. 24 is a section along the line XXIV - XXIV in fig. 22.

Fig. 25 is a similar section as shown in fig. 24.

Fig. 26 is a section showing a design of an adaptation part for a reamer bit in a drilling device according to the invention. Fig. 27 is an exploded perspective view showing a reamer cutter with a pin, wedge and screws.

Fig. 28 is a section along the line XXVIII - XXVIII in fig. 26.

In fig. 1-10 denotes 1 a drill pipe, 2 crown bit, 3 reamer bit, 4 a hydraulic motor, 5 a locking mechanism part, 88. a mechanical means for opening and closing water flow and 6

a cutting device which is fixed to the drill end of the drill pipe 1, and which includes parts 2 - 5 and 88.

The locking mechanism part 5 largely consists of an outer cylinder 7, an inner cylinder 8 and locking hooks 9 as shown in fig. 2. The outer cylinder: 7 is arranged to be displaced axially in relation to and on the mantle surface of the inner cylinder 8 and has an external diameter which enables insertion into the drill pipe 1. The outer cylinder 7 is made with an opening 10 which extends axially, and a convex piece 11 arranged on the inner cylinder 8 projects from the outer cylinder 7 through the opening 10. Inside the opening 10, the convex piece 11 can perform an axial movement necessary to open and close the latches 9 as will be described below.

An annular stepped part 12 is formed on the inner surface of the drill pipe 1 near its end part of the drill end, so that when the convex piece 11 abuts the stepped part 12, the inner cylinder 8 can be prevented from further displacement towards the drill end inside the drill pipe 1 .

The plate-shaped locking hooks 9 are fitted into a recess 13

in the inner cylinder 8, the recess being located closer to the drill end than the convex piece 11 on the cylinder 8. Each of the latches 9 is retained at its lower end by a pin 14 at the end of the recess 13 which faces the drill end, and is designed to swing outwards at its other end 15 about the pin 14 by means of a spring 16

which is inserted between the bottom of the socket and the catch 9.

In the outer cylinder 7 there are openings 17, and the location of these corresponds to the location of the latches 9. When the outer cylinder 7 moves axially towards the surface side in relation to the inner cylinder 8, the latches 9 can by means of the lower edge 18 of the associated opening 17 be pressed down into the recess 13, or when the outer cylinder 7 moves towards the bore side in relation to the inner cylinder 8, the detents 9 can be pushed out through the respective openings 17 with the help of the springs 16. An annular groove 19 in which the detents 9 in the inner cylinder 8 can be fitted when the convex piece 11 on the inner cylinder 8 rests against the stepped part 12 on the drill pipe 1, is assigned to the inner surface of the drill pipe 1, so that when the latches 9 protrude through the openings 17 and fits into the groove 19, the inner cylinder 8 can be locked using the other end 15 of the locking hooks 9, so that it cannot move towards the surface side in relation to the drill pipe.

The inner cylinder 8 will therefore be locked by means of the convex piece 11, the stepped part 12, the latches 9 and the groove 19 so as not to be able to move either towards the drill side or the surface side in relation to the drill pipe 1.

Ribs 20 which extend in the axial direction are arranged in the groove 19. and when the latches 9 with their side surfaces rest against them, the inner cylinder 8 and the drill pipe 1 will not be able to rotate in relation to each other. (This will be described later.)

At the end 15 of each locking hook 9, a notch 22 is taken out into which the upper edge 21 of the opening 17 fits when the locking hook 9 fits into the groove 19, the notch 22 being directly opposite the upper edge 21 of the opening 17. When the edge 21 is fitted into the notch 22, the latch 9 will be prevented from being pushed out of the groove 19 and pressed down into the recess 13 in the inner cylinder 8.

The external diameter of the part of the external cylinder 7 which is made with the opening 10 is smaller than the external diameter of the adjacent part which is closer to the surface, and in the transition part there is assigned an external stepped part 23, so that when the upper edge 21 of the window 17 fits into the notch 22 in the latch 9, the annular, stepped portion 23 will abut against the annular, stepped portion 12 which is formed on the inner surface of the drill pipe 1, and the movement of the outer cylinder 7 towards the drilling side, will thereby be prevented.

Details of the mechanism which prevents relative displacement between the described drill pipe 1 and the inner cylinder 8 are shown in fig. 11 and 12. As will be understood from these figures, the latches 9 are arranged at a distance from the central axis of the inner cylinder 8, and there is thus room for a water channel 35 which extends along the central axis of the inner cylinder 8. As the detents 9 are arranged diametrically offset in the inner cylinder 8, the torque forces produced in the drill pipe 1 can be distributed, and furthermore, no misalignment will occur when the detents 9 engage with the inner surface of the ribs 20.

In the embodiment shown in fig. 2, each locking hook 9 is made with a notch, but the locking hook can also be made with a groove that extends from the end surface and along the side surface as shown in fig. 13a and 13b. In this case, a notch-shaped groove 17' is made in the openings 17 in the upper edge 21, which groove has a width smaller than the width of the opening 17, so that the upper edge 21 of the opening 17 in the outer cylinder 7 can fit into

ten

the groove 22. As described above, any number of locking hooks can also be arranged on the drilling device, in order to thereby achieve a sufficient force to transmit torque and thrust force. By increasing the number of checkmarks, a greater probability of a locked state will also be achieved.

As shown in fig. 3, the stator (non-rotating part) 24 of the hydraulic motor 4 (shown as a hydraulic turbine in the drawing) is arranged to be connected to the inner cylinder at the drill end,

and a rotor 25 (the rotating part) is arranged concentrically inside the stator. The middle part of the rotor 25 is hollow, and in this a circuit 26 is formed from the inner cylinder to the crown cutters 2. 27 be-

denotes a stator blade on the stator side and 28 denotes a rotor blade. A cylindrical changeover valve 29 is arranged axially displaceable in the rotor 25 at its surface side. A flange portion 30 is formed on the end of the changeover valve 29 where this faces the inner cylinder 8. The outer diameter of the flange portion 30 is larger than the outer diameter of the end portion of the rotor 25. A spring 33 is inserted between

a fixing part 32 for the rotor blade 28 and the flange part 30, for thereby

to push the changeover valve 29 against an annular valve seat 34 formed in the inner surface of the inner cylinder 8. A valve opening 36 leading to the bypass 26 from the hollow part 35 of the inner cylinder 8 is arranged inside the end part 31 of the rotor 25. When the crown cutters 2

and the reamer cutters are turned by the hydraulic motor 4 to cut into the soil, the changeover valve 29 will feed water under pressure from the end of the drill pipe 1 facing the surface to the crown cutters 2 through the inner cylinder 8. The pressure to which this water is exposed ,

is significantly greater than the pressure that the water flowing out at the crown cutters 2 through the inner cylinder 8 has when the cutting member 6 is to be pulled up towards the surface side. The change-over valve 29 therefore works in the same way as a general safety valve, as the spring 33 is compressed by the water on the high-pressure side that is supplied for drilling, thereby separating the change-over valve 29 from the valve seat 34, and the hollow part 35 in the inner cylinder 8 will be inserted into connection with a water channel 37 to produce a torque between the stator blade 27 and the rotor blade 28, and the changeover valve 29 will be pressed against the valve opening 36 to close it, so that water is prevented from flowing to the bypass 26 from the hollow part 35 in the inner cylinder 8.

The pressure on the water that flows out at the crown cutters 2 through the inner cylinder 8 when the cutting member 6 is to be pulled up towards the surface side can be significantly less than the pressure on the water that is supplied during the drilling operation. When the cutting member 6 is to be pulled up, the flange part 30 of the changeover valve 29 will therefore be pressed against the valve seat 34 to prevent water from flowing to the water channel 37 from the hollow part 35, so that the rotor 25 cannot turn. The changeover valve 29 will open the valve opening 36 to thereby allow water to flow to the crown cutters 2 through the bypass 26 from the hollow part 35.

As shown in fig. 4 and 5 extend an extension 38 of the stator 24

in the hydraulic motor 4 against the drill side end of the drill pipe 1. An extension 39 of the rotor 25 extends into the extension 38 and the stator 24. The rotor 25 is supported concentrically in relation to the stator 24 by means of bearings 40 and 41 which are arranged between the ends of the extension

39 on the rotor 25 and the extension 38 on the stator 24. In the bearing 40 which carries the extension 39, there is a continuous opening on the rotor side which leads water from the water channel 37 into the extension 39 in order to

produce a torque.

Track 43 which extends axially is arranged at a distance in the outer casing surface of the extension 38 where this faces the drill side. A rectangular pressing piece 44 is inserted in the groove 43, the pressing piece 44

is made with a semi-circular rib 45 which extends in a direction perpendicular to the center line of the cutting member and is fitted into a shallow, arc-shaped, \concave recess 46 formed in the bottom of the groove 43 so as to be able to be turned with the sliding surfaces on both as a base, at the same time the rib 45 is prevented from coming out of the groove 43 by annular springs 48 which are fitted into a concave recess 47 which is arranged in the rib 45 in the surface opposite the sliding surface of the rib, the springs surrounding the extension 38. Moreover, there is a place closer to the surface side than is the case for the annular spring 48, another annular spring 49 of the same type as the spring 48 is arranged to press the side of the rib 45 of the press piece 44 which is closer to the surface side, against the bottom of the groove 43. On the surface side between the bottom of the groove 43 and the press piece 44, a wedge 50 is pressed into the groove 43 in the axial direction. A sliding piece 52 is movably inserted into a groove 51 which extends direction and is taken out in the outer surface of the extension 39. A spring 53 is inserted between the bore side of the sliding piece 52 and the end walls of the groove 51 to thereby push the sliding piece 52 towards the surface side. On the surface side of the sliding piece 52 there is arranged a piston 54 which is in contact with the bottom of the groove 51 and the inner surface of the extension 38. An opening 55 which connects the inner and outer is taken out in the bottom of the groove 43 where this faces the surface side . The wedge 50 and the sliding piece 52 are connected to each other by a screw 56 which

extends through the opening 55. A small hole 57 leading to the inner side of the extension 39 is formed diagonally to the surface side from the surface side end of the groove 51.

The high-pressure water (with a pressure of, for example, approx. 20 kg/cm 2 ) which drives around the hydraulic motor when drilling is taking place, will flow from the hole 42 into the extension 39 on the drilling side, and part of this water will return, the small hole 57 flows into a chamber formed by the groove 51, and the inner surface of the extension 38, will push the piston 54 towards the bore side and push the slide piece 52 towards the bore side and towards the spring 53. Then the wedge 50 which is connected to the slide piece 52 , being pushed in between the press piece 44 and the groove 51, will displace the press piece 44 on the surface side outwards towards the annular spring 49, and will press this against the inner surface of the drill pipe 1.

When the press piece 44 is thus pressed against the inner surface of the drill pipe 1, the extension 38 will be held concentrically with respect to the drill pipe 1 inside it to thereby keep the drilling direction of the crown cutters 2 along the center line.

The pressure with which the water is fed through the circuit 26, when the cutting member 6 is pulled up towards the surface side through the drill pipe 1, is so significantly less than what occurs during drilling, that the spring 53 will push the piston 54 backwards towards the surface side and against this water pressure, the wedge 50 will move towards the surface side, and the annular spring 49 will separate the press piece 44 from the inner surface of the drill pipe 1 and will draw in the outer surface of the press piece 44, so that this lies flush with the open surface of the groove 43. 58 denotes a gap which connects the inner surface of the extension 39 with the groove 51. The gap 58 is arranged closer to the drill side than the small hole 57 and closer to the surface side than the piston 54 when this is in the position closest to the drill side.

In the embodiment described above, a longitudinal groove can be formed in the external mantle surface of the extension 39, and a rod can be used instead of the sliding piece 52. Furthermore, the pressing piece 44 can be formed in the form of a hinge on the extension 38,

as it is articulated by means of a pin arranged on the side surface in the groove 43. Instead of using the wedge 50, a cam groove can also be arranged in both side surfaces of the press piece 44, and a pin which is arranged on the above-mentioned rod can be shot into the cam groove to thereby open and close the press piece 44. Furthermore, it is possible to operate the press piece 44 by connecting the above-mentioned rod with the outer cylinder 7 in fig. 2 instead of using the piston 54 and the spring 53.

According to the structure described above, the crown cutters and reamer cutters can be attached to the drill pipe 1 without producing any oscillation in the locked position, and the drilling direction can be controlled in any desired direction.

A holder is connected to the drill side end of the extension 39

59 for the crown bit, as this extends towards the drilling side from the end of the drill pipe 1. The holder 59 has the shape of a cylinder which is open at both ends and is arranged with a roller-type crown bit 2 on the drilling side. A cutting part 60 of the crown cutter 2 is in the form of a plug screwed into the end part of the holder 59 and is made with central nozzles 61 so that water can be sprayed out from the holder 59 towards the crown cutters 2.

The crown cutter holder 59 is, on the side facing the surface side and away from the crown cutters 2, equipped with three or four openings 62 which are spaced apart.

The openings 62 are designed in such a way that the roll-type reamer cutter 3 and cutter parts 63 which carry these fit exactly into them. The cutter parts 63 which carry the reamer cutter 3 are placed at the end part on the drill side of the holder 59 and are mounted on the end part at one end in the opening 62 by means of a pin 64 in order to be able to swing out of and into the opening 62 with the ends that carry the reamer cutters 3. 65 is a groove in the side surface of the cutter part 63. A stop 66 arranged on the side surface of the opening 62 fits into the groove 65 to thereby regulate the degree of expansion of the reamer cutters 3. 67 denotes a spring which is fitted in a annular groove in the inner surface on the bore side of the opening 62 near the pin 64 and serves to push on the end face of the cutter part 63 to swing the reamer cutters 3 into the opening 62.

An operating tube 68 which causes expansion and collapsing of the reamer cutters 3 is axially displaceable arranged in contact with the inner surface of the cutter holder 59. The operating tube 68 opens at the drill end towards the inner surface of the cutter part 60 and opens at the surface side towards the hollow part of the extension 39. An annular piston 69 is fixed to the surface end of the operating tube 68, so that it is in contact with the inner surface of the cutter holder 59. A convex portion 72 with an inclined surface 71 that slopes downwards towards the drill side is formed on that end of the operating tube 68 which faces the opening 62, so that when the piston 69 is driven towards the drilling side by means of pressurized water during digging and the operating pipe 68 is guided towards the drilling side as shown in fig. 6, the inner surfaces of the cutting parts 63 will be pushed towards the convex part 72, and the reamer cutters 3 will flare out from the outer casing surface of the drill pipe 1 through the openings 62. When the reamer cutter-3 is moved towards the drilling side, in this embodiment the reaction pressure will act on the reamer cutters 3 to expand them further. It is therefore desirable to use such an embodiment which can very well withstand the reaction pressure and will not flare out the reamer blades more than necessary. A spring 70 which serves to push the piston 69 towards the surface side is inserted between the piston 69 and a stepped part 73 which is formed in the inner surface of the cutter holder 59 and is arranged on the outer casing surface of the end of the operating tube 68 which faces the surface . The spring 70 allows the piston 69 to move towards the drill side due to the water pressure which affects the cutter holder 59 during the drilling operation, but pushes the piston 69 back towards the surface side despite the above, reduced water pressure which is due to the water supplied to the crown cutter 2 through the cutter holder 59 when the cutting member 6 is pulled up towards the surface side. At reduced water pressure, the spring 70 moves the operating pipe 68 towards the drilling side, allowing the convex part 72 to move to a groove 74 in the inner surface of the cutting part 63 and allowing the reamer cuttings 3

to pat into the openings62. Slots 75 are formed in the part of the operating pipe 68 that faces the reamer cutters 3, so that water can be fed to the reamer cutters 3 through the openings 62 from the inside of the operating pipe 68.

The water channel is as described above/formed inside the cutting member 6. A closing mechanism part 88 for the water flow which serves to interrupt the introduction of water into this water channel is formed as follows.

The part of the outer cylinder 7 facing the surface side extends towards the surface side longer than the upper end 76 of the inner cylinder 8, and an inwardly facing shoulder portion 77 is formed at the end of the outer cylinder 7. A cylindrical spear head 78 (shown in detail in Fig. 14 and described later) is held axially movably inside the extension of the outer cylinder 7 and partially protrudes from the outer cylinder 7 towards the surface side. The lower end 79 of the spear head 78, which is located inside the cylinder 7, is connected to the upper end 76 of the inner cylinder 8.

The degree of protrusion of the spear head 78 from the outer cylinder 7 is regulated by means of an annular, convex part 81 which is located within the shoulder part 77 of the outer cylinder 7. A cavity 82

is formed between the outer cylinder 7 and the spearhead 78 and between a ring 80 attached to the outer surface of the lower end 79 and the annular convex portion 81. An annular valve 83 which is in sliding contact with the outer surface of the spearhead 78 , is formed integrally with the outer cylinder 7 inside the cavity 82 on the inner surface of the outer cylinder 7. The spear head 78 is made hollow from the upper end 84

which protrudes from the outer cylinder 7, and this cavity extends to the annular convex portion 81. A channel 85 leads to the cavity 82 from the interior of the annular convex portion 81. Moreover, the spear head 78 is made hollow at the lower end 79 to thereby be in connection with the hollow part 35 in the inner cylinder 8. A valve opening 86 which is in connection with the cavity 82 is formed somewhat at a distance from the channel 85. The part between the channel 85 and the valve opening 86 in the spearhead 78 is made compact. As shown in Fig.1, the annular valve 83 on the outer cylinder 7 is arranged so that it is located closer to the bore side than the valve opening 86 in the spear head 78 when the lower end 79

of the spear head 78 is in contact with the upper end 76 of the inner cylinder 8 as shown in fig. 1, and the upper edge 21 of the opening 17 in the outer cylinder 7 fits into the notch 22 on the catch 9 as shown in fig. 2.

Therefore, when the cutting member 6 is locked at the drill pipe 1, the pressurized water that is forced into the drill pipe 1 from the surface side end of the drill pipe 1, will flow into the spear head 78 from the upper end 84 of the spear head 78, will again flow into the spear head 78 through the cavity 82 and the valve opening 86 via the channel 85, and will flow into the inner cylinder 8. The pressurized water will be led from the inner cylinder 8 to the hydraulic motor 4 through the locking mechanism part 5, will push the changeover valve 29 down to close the valve opening 36, will be led through the water channel 37 to produce a torque on the hydraulic motor 4, and will thus turn the rotor 25 in the hydraulic motor 4 to turn the reamer cutters 3 and the crown cutters 2. Part of the pressurized water coming from the hydraulic motor 4 will press down the piston 54 for to spread out the reamer cutters 3, and the other larger part of the pressurized water will flow through the cutter holder 59 to be sprayed on the reamer cutters 3 through the slits or nozzles 75 and on crowns the cutters 2 through the nozzles 61. The water which is fed to the crown cutters 2 and the reamer cutters 3, and which carries the drilling material cut out of the cutters, will flow out on the surface along the outside of the drill pipe 1. The soil can be drilled by simply passing the drill pipe 1 down into the ground without turning it.

When the cutting member 6 is to be pulled up to the surface through the drill pipe 1 by releasing the cutting member 6 from the drill pipe while the drill pipe 1 remains in the ground, the procedure will be as follows.

Before the pull-up procedure is explained, first the spearhead 78 in fig. 14 is described in detail.

As shown in fig. 14, a number of conical holes 91 are assigned there which provide a connection between the interior and exterior of the spear head. The holes 91 extend radially and are spaced from each other on the periphery of the end portion 90 outside the outer tube of the spear head 78. The side of the cone hole 91 which has the smallest diameter is on the hollow side and a steel ball 92 which has such diameter that it can protrude somewhat from the hole with the smallest diameter, is fitted into the hole. The thickness of the outer walls of this end portion 90 is made smaller than the diameter of the steel ball 92,

so that in case the steel ball 92 protrudes from the conical hole 91 on the hollow side, the steel ball 92 will not protrude from the outer surface of the end portion 90. A sleeve 93 having a conical outer surface is fixed in the form of a flange on the outer surface of the end portion 90 to be able

be axially movable. A spring 96 is fitted between a stepped portion 94 assigned to the outer surface of the spear head 78 and a stepped portion 95 assigned to the internal surface of the sleeve 93, so that the sleeve 93 can be pushed outwards towards the end portion 90. The internal surface 97 of the sleeve 93 located on the surface side end of the end portion 90, is designed with such a large diameter that the steel balls 92 can retract toward the outer surface side to at least flush with the inner surface of the end portion 90 and can protrude from the outer surface of the end portion 90. Furthermore, the inner surface of the sleeve 93 between the inner surface 97 and the stepped portion 95 is shaped

with such an internal diameter that it can press the steel balls 92 so that these project into the hollow part of the end part 90 as shown in the drawing.

98 is a stop ring attached to the outer surface of the end portion 90 and

serves to prevent the part between the inner surface 97 of the sleeve 93 and the stepped part 95 from projecting due to the spring 96 beyond the position corresponding to the conical holes 91.

A pull-up wire 100 for pulling the cutting member 6 which is fixed to the drill pipe 1, up to the surface, consists of a flexible pipe which is made by arranging a rubber hose 102 within a layer 101

of cylindrical, twisted wires, or by designing a piece of metal spirally cylindrical. A connecting pipe 104 is connected at one end to the wire 100 by means of a cap nut.

As shown in fig. 16, there is a unit formed at the other end 105 of the connecting pipe 104 which has such a diameter and length that it can be introduced into the stepped part 99 which is formed inside the end part 90 of the spear head 78 in fig. 14. An annular groove 106 into which the steel balls 92 can fit is formed in an outer surface of the connecting pipe 104, this groove corresponding to the conical holes 91 on the end portion 90, when the other end 105 is brought into the tapered portion 91 inside the end part 90 of the spear head 78.

The outer diameter of the middle part 107 of the connecting pipe 104 is larger than the remaining part. Guide members 108 in the form of tubes are divided axially into two parts and face each other on the outer surface of the middle part 107. The outer diameter of the members 108 is slightly smaller than the inner diameter of the drill pipe 1. The connecting pipe 104 is held concentrically in relation to the drill pipe 1 and can be moved inside the drill pipe 1. A plurality of grooves 109 are arranged axially and at a distance in the outer surface of the members' 108, so that when the members 108 are introduced into the drill pipe, water can flow through these grooves 109.

Rod-shaped hooks 111, each of which has the shape of an L-shaped hook

at one end 110, inserted between the members 108 with the L-

shaped parts standing against each other. A semi-circular convex portion 112 is formed on the other side of each hook 111 and is fitted into a shallow arcuate concave portion 113 formed in the outer surface of its largest diameter portion 107 facing the capsule nut 103 Two guide members 108 which are arranged opposite each other are connected to each other by pins 114 which are inserted from the side surface of the track 109 into the members 10R in the centers of the semi-circles in the convex parts 112, and the hooks 111 are designed so that they can be moved at one end 10 with the pin 114 as a pivot point to separate from the connecting pipe 104. The hook 111 extends at one end 110 out over the other end 105 from the connecting pipe 104, so that when the connecting pipe 104 is introduced at the other end 105 to the stepped part 99 in the spearhead 78, the hook 111 can

at the end 110 is hooked onto the sleeve 93 at its end facing the crown cutter 2. A spring 116 is inserted between the other end 115 of the hook 111 and the connecting tube 104 to push the hooks 111 against each other at the ends 110. The hook 111 and the members 108 are connected to each other by the pin 114. The convex portion 112 of the hook 111

fits into the concave part T13 of the connecting pipe 104, and the hook 111 will therefore not move axially in relation to the connecting pipe.

As shown in fig. 18, the wire 100 is wound up on a spool 117

and is connected to a pump 118 at the central axis of the coil 117. The wire 1Q0 is equipped with an overshooter 119 which consists of the above-mentioned connecting pipe 104 and hooks 111, and which is fed into the drill pipe 1 from the surface side. Pressurized water is introduced into the drill pipe 1 to guide the overshooter 119 towards the cutting member 6.

As shown in fig. 19, the overshooter 119, when it has reached the cutting member 6, will push the sleeve 93 on. the spear head 78 with one end 110 of each kroJ-111 against the spring 96, so that the steel balls 92 will protrude from the conical hu.

91 against the inner surface 97 of the sleeve 93. When the hook 111 is moved forward towards the crown cutter 2, as the end 110 slides on

surface of the sleeve 93 during pushing of the sleeve 93, the connecting pipe 104 at the other end 105 will enter the end part 90 of the spear head 78, and when the end 105 comes to the stepped part 99, the end 110 of the hook 111 will protrude somewhat from that end of the surface of the sleeve 93 facing the crown cutter 2, and the spring 96 will therefore push the sleeve 93 back against the frictional force that exists between the end surface of the end 110 and the sleeve 93, the sleeve 93 will fit the steel balls 92 into the groove 106 in the connecting tube

104 and one end of the hook 111 will enclose the surface of the sleeve 93 which faces the crown cutting, so that the connecting tube 104 can be connected inseparably to the spear head 78.

The wire 100 is then wound up using winding devices. 120

and 121 where two sets of conveyor belts are arranged next to each other as shown in fig. 18, and is wound on a bobbin 117.

When the cutting member 6 is pulled upwards by means of the wire 100,

the same wire that was used when the cutting member 6 was led down into the drill pipe 1, the spear head 78 will be pulled towards the surface side and will therefore pull the outer cylinder 7 towards the surface side as the conditions are. The outer cylinder 7 will then move towards the surface side in relation to the inner cylinder 8, and the upper edge 21 of the opening 17

in the outer cylinder 7 will therefore separate from the notch 22 in the detent 9 and will rise further up, and furthermore by movement of the outer cylinder 7 towards the surface side, the lower edge 18 of the opening 17 will push the detent 9 along its edge surface to separate it from the groove 19 in the drill pipe 1 and push it into the recess 13 in the inner cylinder

8 and thus release the cutting member 6 from the drill pipe 1. The cutting member

6 can therefore be pulled up towards the surface side from the lower end of the drill pipe 1. At this point, the relative position between the outer cylinder and the spear head 78 will be the same as shown in fig. 1, and the outer cylinder 7 will have moved towards the surface side in relation to the inner cylinder 8 as shown in fig. 8.

In certain cases, during the drilling operation, it is necessary to add 1,500 liters of water per my. to the drill pipe. However, this amount depends on the size of the device. If approx. 200 liters of water per my. is supplied to the inner cylinder 8 through the hollow cable when the cutting member 6 is pulled up, the water pressure applied to the changeover valve 29 and the pistons 54 and 69 will be so considerably lower than h<y>a which is the case during drilling that the changeover valve 29 will be pressed against the valve seat 34

by the spring 33 to thereby allow water from the hollow part 35 in the inner cylinder 8 to flow to the shear holder 59 through the bypass 26,

and thereby the rotor 25 in the hydraulic motor can be kept stopped. Also, the piston 54 will be pushed towards the surface side by the spring

53 to separate the press piece 44 from the inner surface of the drill pipe 1, the piston 69 will be pushed towards the surface side by the spring 70 and the reamer cutters 3 will be closed inside the openings 62 by the spring 67

in order to be able to pass the drill pipe 1. As the cutting member can thus be pulled up while water is emptied out through the nozzles 61 in the cutting part 60, there will

vacuum is not provided around the crown cutters 2 inside the drill pipe 1 and in the drilled hole in the ground. Therefore, the walls in the borehole will not clap together, and it will be possible to reduce the necessary pull-up force.

As will be understood from the above explanation, the speed used to pull the cutting member 6 from the drill side end of the drill pipe 1 can, with the present invention, be increased to a considerable extent compared to before, and the force required to wind up the wire,

can be reduced.

The hollow wire 100 can be connected at one end directly to the cutting member 6, so that the water needed during drilling can be supplied through the wire 100. However, as mentioned above, a large quantity of water must be supplied to the crown cutters during drilling, and the cross-sectional area of the wire is much smaller than the drill pipe. To add the same amount of water per unit of time through the wire, and to overcome the higher flow resistance compared to supplying water through the drill pipe, a higher pressure pump is required, which consequently results in higher operating costs. When the wire is hung on the drill pipe during the actual drilling, not only will the wire be fatigued by the weight it is exposed to and thereby have a reduced service life,

but it will also be necessary to reel out wire in accordance with the speed used when inserting the drill pipe into the ground, and in the event that drilling is carried out by turning the drill pipe, there will be

friction between the inner surface of the drill pipe and the wire, and means are therefore necessary to avoid this, which means that the operation will be complicated. However, when the wire is removable from the cutting member to be used only for pulling up the cutting member, there will be advantages in that the operation can be simple and that operating costs and expenses for equipment can be reduced.

The cutting member 6 is guided towards the drill side from the surface side of the drill pipe 1 and is locked at the drill side end as follows.

As shown in fig. 8, the outer cylinder 7 is pulled towards the surface side in relation to the inner cylinder 8 and is fed into the drill pipe 1 while the latches 9 are closed. Then, e.g. 750 liters of water per my. into the drill pipe 1 from the surface side end, and the cutting member 6 is guided towards the drill side through the drill pipe 1 with the help of this water. Since around the outer surface of the outer cylinder 7 there is arranged a rubber ring 89 which has such a diameter that it touches the inner surface of the drill pipe 1, as shown in fig. 2, the pressure in the water fed into the drill pipe will first affect the rubber ring 89 and the shoulder part 77 of the outer cylinder 7 to displace the outer cylinder 7 towards the drilling side in relation to the inner cylinder 8. Thereby, the lower edge 18 of the opening 17 which pressed the detent 9 inwards, moves towards the drilling side and the detent 9 will protrude through the opening 17 to a half-open position as shown in fig. 10, as it will touch the inner surface of the drill pipe 1 and will move as it is dragged along the inner surface of the drill pipe 1. Furthermore, the outer cylinder 7 will move towards the drill side, but as the catch 9 is half way out, the upper the edge 21 of the opening 17 will not be able to fit into the notch 22 of the detent 9, and the outer cylinder 7 will be prevented from moving towards the bore side relative to the inner cylinder 8. On the other hand,

as the part between the channel 85 and the valve opening 86 is compact, the water pressure will also affect this part to bring the spearhead 78 into contact with it. inner cylinder 8 as shown in fig. 9. But since the outer cylinder 7 is located on the surface side in relation to the inner cylinder 8 due to the depth of the notch 22 in the detent 9, the annular valve 83 located on the inside of the outer cylinder 7 will close the valve opening 86 in spear head 78, as shown in fig. 9.

When the cutting member 6 is to be guided towards the drilling side by means of it

water fed into the drill pipe 1, the water flow closure mechanism part 83 will therefore act to prevent the water from passing through the cutting member 6. The cutting member 6 will therefore be able to be efficiently fed into the drill pipe 1, while a torque will not be provided by the hydraulic motor 4 to spread out the reamers 3 due to the centrifugal force, and the inner surface of the drill pipe 1 will be prevented from being destroyed.

In the above-described embodiment, the water flow closure mechanism portion 88 is formed generally of the spear head 78 and the outer cylinder 7. However, it may be formed of the outer cylinder 7 and the inner cylinder 8 and may function by coincidence or non-coincidence of holes which are designed in both parts. Moreover, the changeover valve 29 can also be designed so that it can function together with the outer cylinder without the use of the spring 33. The opening and closing mechanism for the reamer cutters 3 can also be modified. Any known reamer cutters can also be used. The hydraulic motor 4 can be of the turbine type, screw pump type or any other type. The rotor can be arranged externally and the stator can be located internally. The crown cutters 2 used can be cutters for boring out drill cores.

(

According to the embodiment of the inventive device described above, the hydraulic motor is directly connected to the drilling rig, and the cuttings can be guided to the lower end of the drill pipe and can be pulled up through the drill pipe while the hydraulic motor is at a standstill. The flow of water into the cutting device can be adjusted to the correct value, and the drilling work can be carried out efficiently.

In the following, the embodiment of fig. 21 and 22 be described in detail.

In contrast to the embodiment in fig. 1 - 10, the drilling force in this embodiment is transferred to the drill pipe from the surface, as in the conventional example, and there are also other differences from the structure of the above-mentioned embodiment, but the basic idea is the same as for the described embodiment, and it should be over - it is easy to say that the features of this embodiment can be transferred to the embodiment in fig. 1 - 10.

In fig. 21 and 22 are the same parts that appear on the embodiment of fig. 1 - 10, denoted by the same reference numerals. 1 denotes a drill pipe, the same as used in a conventional drilling device, and depending on the depth of the borehole to be drilled, a number of drill pipes 1 are used there which are connected in turn. As will be explained in more detail in the following, the drill pipe 1 will mostly exert a torque and a thrust force downwards into the ground to the crown cutters 5 which are locked to the drilling end of the drill pipe.

The crown cutting 5 is designed so that it can be fixed to the lower end 122 of the inner cylinder 8. The outer cylinder 7 is assigned to the outer mantle surface of the inner cylinder 8 in order to be displaced axially in relation to the inner cylinder 8. The outer cylinder 7 and crown cutter 5 have such diameters that they can be fed into the drill pipe 1.

Concave grooves 123 which extend in the axial direction are formed in the outer surface near the lower end 122 of the inner cylinder 8. A reamer blade 3' of such width and length that it can fit into the concave grooves 123 is pivotally supported about a pin 64' which is located in the groove 123 near the lower end 122 of the cylinder 8, in order to be able to swing in and out of the groove 123 around the pin 64'. This reamer blade 3' is provided with diamond crystals that protrude in the same way as the blades 5 on the outer surface in order to be able to cut soil and sand when they are out of the groove 123.

The locking hook 9 can swing around the pin 14 at one end. The locking hook extends in the axial direction towards the upper end 76 of

the inner cylinder 8 and can protrude at its other end through the opening 17 which is taken out in the outer cylinder 7, the protrusion being effected by means of the spring 16 which is arranged between the other end and the inner cylinder 8.

A convex part 11 is fixed to the inner cylinder 8 and projects

out through the opening 10 which is formed in the outer cylinder 7. The opening 10 has such an axial length that the convex part 11 can shift in the axial direction inside the opening, so that the necessary, relative, axial movement between the inner cylinder 8 and the outer cylinder 7 can be performed.

The outer cylinder 7 extends at its lower end 124 to the concave groove 123 in the inner cylinder 8. A recess 125 is formed in the axial direction, and the reamer cutter 3' can be fitted into it.

A pin 126 extending towards the inner surface is provided

near the end part of the inner surface, just opposite the recess 125

and is adapted in a groove 127 which is formed in each side surface of the reamer cutter 3'. The groove 127 extends in the form of an S in the longitudinal direction in the side surfaces of the reamer bit 3', so that when the outer cylinder 7 is moved axially in relation to the inner cylinder 8, the reamer bit 3' can be turned with the pin 64' as the axis of rotation, as it either can be accommodated in the concave groove 123 or can protrude from the drill pipe 1 from the groove 123.

An annular part 128 is arranged on the inner surface of the drill pipe 1, so that the convex part 11 of the inner cylinder 8 can come into contact with it. When the part 11 collides with the annular part 128, the reamer cutters 3' and the crown cutters 5 can protrude from the lower end 129 of the drill pipe 1, while the other parts can be held back inside the drill pipe 1.

The groove 19 is formed in the inner surface of the drill pipe 1,

so that it lies just opposite the detent 9. When the outer cylinder 7 is displaced in relation to the inner cylinder 8 so that the reamers 3' can protrude from the drill pipe 1, the detent 9 will protrude through the opening 17 and fit into the groove 19 in drill pipe 1.

The inner cylinder 8 can therefore be locked so that it cannot move towards the drill side or the surface side by means of the groove 19, the annular part 128 on the drill pipe 1 and the reamer cutters 3' and the part 11 on the inner cylinder 8, while the reamer cutters 3' and the crown shears

5 protrudes from the lower end 129 of the drill pipe 1. The reaction force acting on the drill pipe 1 from the surface towards the drill side by this mechanism will be transferred to the crown bit 5 and the reamer bit 3'.

The rib 20 which extends in the axial direction is arranged in the groove 19 in the drill pipe 1 so that when the side surfaces of the detent 9 touch the wall 22, the torque applied to the drill pipe 1 will be transferred to the inner cylinder 8 and the crown cutters 5 and reamer cutters 3' can be turned together with the drill pipe 1 (as described above).

In the same way as described in connection with the above-mentioned embodiment, the catch 9 is made with a notch 22.

To transfer the rotation of the drill pipe 1 to the inner cylinder

8, any other part, e.g. the convex part 11 is used. Swinging out and in of the reamer cutters 3' at the lower end 124 of the outer cylinder 7 can also be carried out by the surfaces of the reamer cutters 3' facing the inner cylinder 8 coming into engagement with the lower end 124 of the outer cylinder 7.

When the outer cylinder 7 is moved towards the upper end 76 relative to the inner cylinder 8, the reamer bits 3' will be folded in and will be within the inner surface of the drill pipe 1 and will be able to pass through the drill pipe 1, but the outer cylinder 7 is moved upwards in relation to the inner cylinder 8 to swing in the reamer cutters 3', the upper edge 21 of the opening 17 will simultaneously separate from the notch 22 in the latch 9 and the outer cylinder 7 will be able to be pulled up. When the reamer cutters 3' are folded together and are within the inner surface of the drill pipe 1 and when the outer cylinder rises further, the lower edge 18 of the opening 17 will push the detent 9 on its outer edge surface to turn it inwards, and the detent 9 will separate from the groove 19 in the drill pipe 1, so that the inner cylinder

8 can be moved towards the surface side in relation to the drill pipe 1.

If a large cutting resistance acts on the cutters of the reamer cutters 3f during drilling, and this resistance acts in the direction inward of the reamer cutters, the resistance will cause a force that pushes the outer cylinder 7 up towards the surface side, and the force will push the outer cylinder 7 towards surface side in relation to the inner cylinder 8. When the outer cylinder 7 rises in this way, the catch 9 will separate from the groove 19 in the drill pipe 1 as described above, and the inner cylinder 8 will enter the drill pipe 1 in its entirety, so that no further drilling is carried out. The mechanism for preventing this will be explained below.

A recess 130 is formed in the upper end 76 of the inner cylinder 8. An inner locking hook 131 can at its one end swing around a pin 132 into the recess 130 and can at its other end 133 project out of the recess 130 by means of a spring 134. A sliding tube 135 is arranged between the inner cylinder 8 and the outer cylinder 7 and can be displaced axially on the surface. The locking hook 131 can protrude at its other end 133 through an opening 136 which is taken out in the sliding tube 135. The outer cylinder 7 has a groove 137 that fits the end 133 of the locking hook 131 as shown in the drawing, when the outer cylinder 7 plays up ream the flanges 3' from the drill pipe 1, so that the ratchet 9 can fit into the groove 19 in the drill pipe 1. When the ratchet end 133 protrudes through the opening 136 and fits into the groove 137, the outer cylinder 7 will be prevented from being able to rise in relation to the inner cylinder - from the position where the reamer cutters 3' and the locking hook 9 play out.

In this embodiment, the outer cylinder 7 extends further into the shoulder portion 77' than the upper end 76 of the inner cylinder 8, while being closed. A pull-up spear head 78' is axially movably fitted inside and outside the outer cylinder 7, and a sliding tube 135 is connected to a part 138 which is held integrally with the pull-up spear head 78' inside the outer cylinder 7 The length that the spear head 78' extends out of or into the outer cylinder 7 is regulated by a flange part 139 arranged within the shoulder part 77" of the outer cylinder 7 and the part 138 which is arranged inside the cylinder 7. A spring

140, which pulls the spear head 78' towards the side facing the inner cylinder 8, is arranged between the inside of the shoulder part 77' and the flange part 139 inside the outer cylinder 7 of the spear head 78'.

When the spring 140 is compressed to pull the spearhead 78' out of the outer cylinder 7, the slide tube 135 will be pushed against the shoulder portion 77' of the outer cylinder 7 between the inner cylinder 8 and the outer cylinder 7, so that the catch 131 at its end 133 is released from the groove 137 in the outer cylinder 7 by means of the lower side edge 141 of the opening 136 in the slide tube 135 and can be pushed into the recess 130

in the inner cylinder 8.

As will be understood from the preceding description, the drawing shows the inner cylinder 8 secured to the drill side end of the drill pipe 1, when this is ready for drilling. When the drill pipe 1 is rotated on the surface and pressurized water is supplied to the drilling side, a hole will be drilled with the help of the crown cutters 5 and the reamer cutters 3' will expand the hole drilled with the crown cutters, so that the drill pipe 1 can be guided downwards. During the drilling operation, water under pressure will be supplied from the surface side into the drill pipe 1 and into the hollow part 35 of the inner cylinder 8, through hole 14 2 which is formed in the shoulder part 77' of the outer cylinder 7, and this water is sprayed out through nozzles 143 in the crown cutters 5 to cool these and then cool the reamer cutters 3', and the excavated mass resulting from this drilling operation is emptied onto the surface via the outside of the drill pipe 1. The crown cutter 5 can be a cutter for drilling out cylindrical drill cores for use as geological samples, and a sleeve to accommodate the drill core may be arranged inside the inner cylinder 8.

The crown cutters 5 will wear during the drilling process. When the drilling speed for the drill pipe 1 has been reduced so much that it is necessary to replace the crown cutters 5, or when the drilling depth corresponding to the length of the drill core that can be accommodated in the sleeve has been cut out, a pull-up tool can therefore be attached to a cable is fed down into the drill pipe 1 from the surface side and connected to the spearhead 78'.

When the wire is tightened on the surface to pull up the spear head 78' towards the surface, the sliding tube 135 connected to the spear head 78' will move towards the side of the outer cylinder 7 which faces the shoulder part 77 and the lower side edge 141 of the opening 135 will release the catch 131 by its end 133 from the groove 137 in the outer cylinder 7. When the outer cylinder 7 is then pulled towards the surface to rise in relation to the inner cylinder 8, the reamer cutters 3' will snap together to lie within the inner surface of the drill pipe 1, and the catch 9 will be released from the groove 19 in the drill pipe 1 at the lower edge 18. Therefore, when the wire is pulled further up towards the surface, the inner cylinder 8 which carries the crown cutters 5 and the reamer cutters 3', will be able to be pulled up to the surface, as the drill pipe 1 left in the soil.

When the crown cutters 5 have been replaced and the geological sample (drill core) that has been cut out of the soil has been taken out of the sleeve that houses the drill core, the cutting device consisting of the inner cylinder 8, the outer cylinder 7 etc. is led down towards the drilling side as follows.

In the unaffected state, the spear head 78' is placed near the side of the inner cylinder that faces the upper end 76, and the locking hook 131 can protrude at its other end 133 through the opening 136 in the sliding tube 135. If the reamer cutters 3<*> and the catch 9 on the surface protrudes from the outer cylinder 7 as shown in the drawing, the catch 131 will also fit into the groove 137 in the outer cylinder 7. When the spear head 78'' is pulled towards the side where it comes out of the outer cylinder, therefore the detent 131 is released from the slot 137, the crown cutters 5 are retained and the inner cylinder 8 is pulled towards the crown cutters 5 from the outer cylinder 7. The reamer cutters 3' and the detents 9 will swing in so that the cutting member can be pushed through the drill pipe 1. If the spearhead 78' is released, it will partially return into the outer cylinder 7 due to the spring 140, and as the inner cylinder 8 is moved to the side of the outer cylinder 7

which faces the lower end 124 in relation to the outer cylinder 7, the catch 131 will protrude through the opening 136 in the sliding tube 135 to make contact with the inner surface of the groove 137 in the outer cylinder 7 on the side facing the lower end 124.

In this state, the cutting member is brought in towards the lower end of the drill pipe 1 by means of pressurized water, or the like. When it reaches the drilling side or the drilling end of the drill pipe 1, the convex part 11 of the inner cylinder 8 will touch the annular convex part 128 on the inner surface of the drill pipe 1, and the crown cutters 5 and the reamer cutters 3' will protrude past the end part 129 of the drill pipe 1. The water that is fed under pressure into the drill pipe 1 from the surface will push the outer cylinder 7 down like a piston, it will first spread out the reamer cutters 3', will then fit the catch 9 into the groove 19 in the drill pipe 1, will fit the locking hook 131 into the groove 137 in the outer cylinder 7 and will lock the cutting member to the lower end part of the drill pipe 1 to thereby enable drilling in the soil.

A rubber ring 144 arranged in the form of a piston ring on the outer mantle surface of the outer cylinder 7 serves to guide the cutting member towards the drill side end of the drill pipe 1 under the influence of pressurized water and to prevent pressurized water from flowing out of the drill pipe 1 between the outer cylinder 7 and the drill pipe<:>1.

In the above-mentioned embodiment, the locking hook 131 can be designed as a block and can be accommodated in the groove 130 in the inner cylinder 8 to thereby be able to enter and exit the groove 130 in the same way as the reamer cutters 3' by means of the axial edge of the opening 136

in the sliding tube 135.

According to the present invention, a drilling device can be obtained where the crown bits and reamer bits can be held securely at the drill end of the drill pipe 1 by being guided through the drill pipe 1 and can be pulled up to the surface while the drill pipe 1 is buried in the ground.

In the embodiment described above, the reamer cutters 3'

the same as in fig. 22.

Fig. 23 and 24 show the case where four reamer cutters 3' are arranged in each recess 123 in the outer mantle surface of the inner cylinder 8. Even reamer cutters 3' of such a shape are not a particular disadvantage of the drilling device according to the present invention. However, since the reamer cutters 3" are of the same type as reamers in cutting tools for machine tools, it is desired to increase the number ay of reamer cutters retained on the outer surface of the inner cylinder 8, in order to increase the cutting capacity.

If six reamer blades 3' are secured to the inner cylinder 8, as shown in fig. 25, by means of such pins 64<*> as are shown in Figs, 23 and 24, which is evident by comparing Figs. 24 and 25, the material 145 in the outer surface portion of the portions carrying the pins 46' will become so thin that it will cause strength problems. With this construction, therefore, the number of reamer cutters will not be able to be increased as much as in fig. 25.

As shown in fig. 26 - 28 there is therefore arranged a semicircular groove 146 which faces the outside of the groove 123 and extends in a direction perpendicular to the center line of the inner cylinder 8

at one end of the reamer blade 3<1>, and a pin 64'' with a columnar-shaped surface 147 is secured to the inner cylinder 8 with screws 148 outside both ends of the slot 146, so that the columnar-shaped surface 147 can fit into the semicircular groove 146. Of course, the surface of the reamer bit 3' which touches the bottom 149 in the groove 123 will have a curved surface 150, so that the reamer bit 3' can rotate freely at the other end with the pin 64<11> as pivot axis.

Thus, with this embodiment, more reamers 3' can be mounted to the surface of the inner cylinder 8 than was the case with the reamers 3" with the pins 64' in Fig. 23 <p>g 24. The embodiment in Fig. 27 will also provide sufficient mechanical strength.

However, the reamer cutters 3' will only be held in the inner cylinder 8 on one surface by the pins 64''. In the case of expansion of the borehole during cutting in the borehole walls with the reamer cutters 3', the force resisting twisting of the reamer cutters 3' will therefore be reduced. In order to strengthen it, an axial wedge groove 151 is made in the surface of the reamer cutter 3' which lies on the opposite side of the groove 146 and in the bottom 149 of the recess 12 3 just opposite said surface, and a common wedge 152 is inserted into the wedge groove 151 , so that a greater resistance to twisting of the unrolling cutters 3' can be provided. A rib and a groove extending in the axial direction in the inner cylinder 8 can be formed between the reamer blade 3' and the groove 123 and can by adaptation

to each other is used instead of the wedge.

In the embodiment described above, the present invention is applied to a cutting support member which, during use, is secured to the drill side end of the drill pipe by means of a locking member. so that the reamer cutters can be spread out and folded together in cooperation with a mechanism in the locking device which causes the locking hooks to swing out and in. The present invention can also be used in such constructions where the unfolding and folding of the reamer blade is carried out with the aid of hydraulic pressure as in fig. 1 - 10. The invention can also be used in cases where the borehole is to be expanded without a crown cutter or in the case where the crown cutters are used to collect drill cores (geological samples).

Claims (5)

1. Drilling device comprising a drill pipe and a cutting device (6) equipped with a motor device which can be inserted into a borehole through the drill pipe, and which exhibits a central drilling tool and swiveling in and out reamer bits (3) which can be passed unhindered through the drill pipe, as well as a locking mechanism cooperating with the drill pipe consisting of an inner cylinder (8) which is enclosed by an outer cylinder (7) which can be displaced axially in relation to the inner cylinder (8), locking hooks (9) which by relative displacement between the cylinders (7, 8 ) can be swung out and in for locking in, respectively releasing from recesses in the inner wall of the end of the drill pipe that faces the bottom of the borehole, and a spear head (78) arranged at the upper cylindrical end for connecting an overshooter (119) at a pulling device which, by pulling the spear head, causes the detents (9) to swing in and brings the cutting device (6) to the surface, characterized in that the detents (9) are stored at their lower ends, above the opening the jaws (3), on the inner cylinder (8) by means of pins (14) and can be swung out through windows (17) in the outer cylinder (7), and that the spear head (78) is arranged displaceable in relation to the cutting member's ( 6) two cylinders (7, 8) for forming further locking devices (131, 137) and/or channel and valve devices (83, 86) for drilling fluid. 2. Drilling device as stated in claim 1, where the cutting device (6) comprises a hydraulic motor device (24 - 28) consisting of a turbine or similar formed by a rotor (25) as the crown cutters (2) and the reamer cutters (3) in the cutting device (6) is connected to, and a stator which is attached to the inner cylinder (8) and comprising a water channel between the rotor connected to the inner cylinder and the blades and the stator, characterized in that the spearhead (78) together with the outer cylinder ( 7) forms an annular valve (83, 86) whose opening (86) in an extension (79) of the spear head (78) opens into a hollow part (35) in the inner cylinder (8) for supplying water to the water channel in the hydraulic motor device (24 - 28), and which can be closed by an annular valve (83) on the outer cylinder (7) when the spearhead (78') is retracted in the insertion position (fig.1, 8, 9). 3. Drilling device as stated in claim 1, characterized in that inner locking hooks (131) which are separate from said locking hooks (9) are arranged at the upper end (76) of the inner cylinder (8), that a sliding tube (135) which has openings (136), and which cooperates with the spearhead (78'), is inserted axially movable between the inner cylinder and the outer cylinder, so that the inner locking hooks (131) can be brought out through the opening (136) in the sliding tube (135) by means of springs (134) and fit into a groove (137) formed in the inner surface of the outer cylinder (7), when the other end of the detent and the upper edge of the opening in the outer cylinder are engaged with each other, and are pulled into the opening (136) in the slide tube (135) when the spear head (78') is pulled up (fig. 21). 4. Drilling device as specified in claim 1, characterized in that each detent hook (9) which at one end is pivotally supported on the inner cylinder by means of a pin (14), is designed with a notch at its other end (15) (22) and is arranged in a direction that deviates from the radial direction of the inner cylinder (8) (fig. 11, 12) 5. Drilling device as specified in claim 1, characterized in that the other end (15) of the locking hook (9) is designed with a narrower part that fits into a notch (17') in the upper edge (21) of the opening (17) ) in the outer cylinder (7) (fig. 13a, 13b).