NZ516007A

NZ516007A - Device for drilling a conical zone in a hole

Info

Publication number: NZ516007A
Application number: NZ516007A
Authority: NZ
Inventors: Per Age Faanes
Original assignee: Quick Anchor As
Priority date: 1999-05-26
Filing date: 2000-05-26
Publication date: 2002-07-26
Also published as: NO992514D0; JP2003500226A; HUP0201889A2; MXPA01012101A; WO2000073005A1; AU4957700A; EP1187693A1; CZ20014238A3; PL352298A1; CN1361722A; CA2375240A1

Abstract

A device for drilling a conical area in the innermost part of a previous drilled cylindrical hole is disclosed. This produces a safe and durable fastening for screws and bolts in concrete, rocks and other solid materials.

Description

1 PCT/NOOO/OOl 77 Device for drilling a conical zone in a hole The invention regards a device for drilling a conical zone at the bottom of a prednlled cylindrical hole. The device is especially intended for drilling m concrete, rock, stone 5 and other solid materials The device of the invention makes it possible to provide secure anchorage for a taper bolt at the bottom of the drilled hole.

It is previously known that a certain amount of conisity may be formed at the bottom of a drilled hole, and that this may be done by use of various types of devices and drills A 10 great drawback to these solutions is the fact that they are complicated and often do not give satisfactory results, in addition to the fact that no compressed air or dnil fluid is fed to the hole dunng drilling This results in the dolled materials remaining at the innermost end of the hole and having to be removed by means of e.g compressed air after the conical area has been dolled Unlike these known solutions, the device of the 15 invention ensures that compressed air is introduced, so as to remove the dolled matenals while the drilling takes place.

The basis of the invention is the fact that it is often difficult to create solid and firm anchorage points in rock, stone, concrete and similar hard mateoals It turns out that :o only cylindocal holes are normally dolled for fixing bolts and screws in these materials. In other words, the bolts are only held by the fnctional forces between the bolt and the cylindocal. straight wall.

Use of the device of the invention to doll a conical area at the bottom of a cylindocal 25 hole will provide a much stronger and firmer anchor at the innermost end of the dolled hole.

Various ways of dolling conical holes have previously been descobed EP 704 226 is especially aimed at a device for dolling holes m face tiles. DE 2 415 240 describes a 30 method and device for dolling conical holes. US 5 829 925 descobes a doll with a cutting device at the end, which device may be forced out by means of pressunsed doll fluid US 4 978 258 is aimed at a drilling tool with a swing-out head for dolling cavities i PCT/NOOO/OOl 77 The present invention regards a device for drilling a conical zone at the end of a predrilled cylindrical hole in rock, stone, concrete, bricks or other dnllable material for fixing screws, safety bolts, the device being characterised in that it comprises a replaceable drill head coupled to a swing-out cone joint with a resilient O-nng, where the ball joint is attached to the drill head by use of a through bolt, and where the dnll head, the bolt, the ball head with the cone joint have through holes for introduction of compressed air or dnll fluid for removal of dnlled matenals By both the dnll head and the cone joint having through holes for introduction of compressed air or drill fluid, even at all angles of the cone joint, the dnlled hole will at all times be free of drilled matenals. cuttings and other loose matenals When dnlling large holes m rock and coning the lower part of the hole, great forces must be applied to the actual drill head in the form of powerful blows and rotation The device of the invention is formed with a ball joint m which the actual ball is to withstand the percussion forces applied and a sturdy through bolt is to withstand the rotational forces.

The invention will now be explained m greater detail by means of the figures, in which Fig 1 shows a cross section of the entire dnll head with a ball-attached joint and a swing-out cone joint, Fig. 2 shows a cross section of the cone joint, seen from the side.

Fig. 3 shows a top view of the drill head, Fig 4 shows a conventional rock drill at the bottom of a drilled hole. Fig. 5 shows the cone joint of the invention while drilling a conical bottom. Fig. 6 shows an example of a taper bolt that has been hammered down and secured Figures 1. 2 and 3 show the dnll head 1 with a threaded portion 3 that is screwed onto a dnll rod The cone joint 2 that can be forced outwards to dnll a conical hole is attached by use of a through bolt 4 The bolt 4 has a hollowed out area 14 in the middle, so as to allow compressed air to pass through in all positions of the cone joint 2 Carbide segments 5 have been mounted on the side of the cone joint 2 facing the drilled hole These will ensure quicker, improved drilling of the conical area and make the dnll more durable A central passage 11 and 13 for introduction of compressed air goes through the dnll and the cone joint 2 A hollowed out area 12 exists in the region between the cone joint 2 and the dnll head, the function of which area is to ensure the free passage of compressed air even when the cone joint 2 is in its extreme position. In figure 1, the broken line 9 illustrates the bottom of the drilled hole, and the broken line 8 shows the ready dnlled conical zone A rubber O-nng 15 is fitted to the upper part of the cone joint 2. the effect of which is to force the cone joint back to its onginal position after dnlhng The lower edge of the cone joint 2 is rounded with a bevel 6. When the cone joint 2 reaches the ready drilled position, the cone joint will come to a stop against the lower stop edge 10 of the dnll head. Thus this edge ensures the maximum deflection of the cone joint.

Figure 3 shows the drill head 1 with the cone joint 2 seen from above, with carbide segments 5 The through bolt 4 is indicated by broken lines, and provides swivelling attachment of the cone joint 2 to the drill head.

Figure 4 shows a conventional rock drill 16 dnlling a cylindncal hole in rock 17 The drilling is earned out until the hole has reached the desired depth 9 Figure 5 shows the hole dnlled in Figure 4, but with the cone joint 2 mounted on a dnll head and a conical hole 8 dnlled at the bottom of the hole Due to the lower bevel 6 of the cone joint, the joint will, as a result of rotation and hammenng on the dnll head, be forced outwards and will drill a conical hole 8 The swivel radius of the cone part is limited as it hits the lower stop edge 10. When the conical hole is ready drilled, the rotation and hammering on the drill head is stopped At this point the rubber O-nng 15 will force the cone joint back to its onginal position, to allow the whole thing to be withdrawn from the hole Dnlled matenals will already have been earned out of the hole by compressed air Figure 6 shows an example of a taper bolt 18 that has been inserted into the hole A pipe 19 is then placed around the outside of the taper bolt 18 and knocked down towards the 4 bottom of the hole As a result of the force applied during the hammering, the pipe 19 is forced out by the conical part of the bolt 18 and fills the surrounding space. This provides a very safe fixing and anchoring system The diameter, length and angle of the cone joint may be adapted to the desired dimensions.

The entire dnll head and the cone joint are preferably provided with standard special threads These are matched to the thread used on dnll rods for drilhng in rock, stone, concrete and similar, for securing and anchonng conventional rock safety bolts and other fastening devices. By using special standard thread, drill heads and cone joints may be replaced quickly

Claims

Claims 1.

A device for drilling a conical zone at the end of a dnlled cylindncal hole in rock, stone, concrete or other drillable matenal, for fixing screws, safety bolts or similar, characterised in that the device compnses a drill head (1) coupled to a swing-out cone joint (2) with a flexible and resilient O-nng (15). and the dnll head and the cone joint have a through passage (11, 13) for introduction of compressed air or drill fluid
2 A device according to Claim 1, characterised in that the swing-out cone joint (2) is attached to the drill head (1) via a solid through bolt (4), the conejomt (2) may swing out to a predetermined radius (8) by coming to a stop against an edge (10) at the bottom of the dnll head
3. A device according to Claims 1 - 2, characterised in that the cone joint (2) is equipped with at least one, preferably three longitudinal carbide segments (5)
4. A device according to Claim 1, characterised in that the O-nng (15) on the cone joint (2) is preferably made from a flexible, resilient rubber.
5 A device according to Claims 1 - 4, characterised in that compressed air may be introduced through the passages (11, 13) WO 00/73005 0 PCT/NOOO/OO177
6 A device according to Claims 1 - 5. characterised in that the device is equipped with standard thread, so as to allow it to be coupled to commonly used drill rods.
7 A device according to Claims 1 - 6, characterised in that the cone joint (2) has a hollowed out area (12) at the top in order to enhance the transfer of compressed air between the passages (11) and (13).
8. A device for drilling a conical zone at the end of a drilled cylindrical hole in rock, stone, concrete or other drillable material substantially as hereinbefore described and with reference to the accompanying drawings. Quick Anchor AS by their authorised agents JAMES & WELLS ■ wv-s Gi ::cy if* 7;fJ (;""■> ir" fr^ ;* r \\ n r' r=s k ^»: n V j, L J