MXPA97007336A - Rock drilling tool, bit and method to transfer percus energy - Google Patents

Abstract

The present invention relates to a rock drilling tool for percussion drilling comprising a drill bit (11) and a drill pipe (12) cooperating through a shoulder stop in a threaded connection. The connection comprises at least one male thread (17) and one female thread (18). The thread (17) is provided on a pin (19) which is an integral part of the drill bit (11). The drill bit is provided with a shoulder (20) at the inner end of the pin (19) such shoulder has a stop surface (21) facing the free end of the pin (19). The female thread (18) is provided in the drill pipe (12) and the free end of the drill pipe is provided with an impact surface (23). The threads (17, 18) are cylindrical. The present invention is characterized by the combination of the shoulder stop with a short head and a straight transfer energy to the rock drilling tool. The invention the percussion energy from a rock drilling tool towards a hole

Description

ROCK PERFORATION TOOL. BIT AND METHOD TO TRANSFER PERCUSSION ENERGY DESCRIPTION OF THE INVENTION The present invention relates to a rock drilling tool for percussion drilling comprising a drill bit and a drill pipe. The drill bit has a head having a front surface, from which a number of front inserts project and peripheral inserts are provided in a peripheral row, the drill bit is provided with a first thread cooperating with a second thread provided on the drill pipe. The invention further relates to a drill bit and to a method for transferring percussion energy from a rock drilling tool into a hole. It has previously been known, through US-A-1, 447,855, to provide a so-called shoulder stop in threaded connections between a drill rod and a rock drill bit in percussion drilling equipment. When loosening the drill bit in the known equipment with a relatively heavy drill bit, there is a risk that the entry of the thread into the drill pin is damaged due to the substantial difference in mass on the opposite sides of the shoulder stop. . In addition, the known drill bit is provided with hardened steel chisel edges, which project relatively far in the radial direction. This means that the percussion energy during percussion drilling is forced to flex towards the radially outer edge of the edge and, therefore, the effective coefficient of efficiency is reduced, resulting in a damaged guidance ability and speed damaged perforation The chisel edges give a relatively slow drilling speed. In addition, it appears that the known tool may have a stop between the bar and the drill bit, both in the radial and axial directions, which during drilling create the hardening of the material with subsequent points of initiation of rupture. It is an object of the present invention to provide a method for transferring percussion energy from a rock drilling tool to a drilling hole, such as providing good bit guidance, acceptable loads and also good energy transfer. Another object of the present invention is to provide a rock drilling tool comprising a rigid connection, which does not flex despite the difficult angles of attack. A further object of the present invention is to provide a rock-forming tool, which has a good coefficient of efficiency, making the drill bit as light as possible simultaneously with the measurement that the entrance of the pin is avoided, during the loosening, due to the low weight of the bit. A further object of the present invention is to provide a rock drilling tool, through which a good life span can be obtained simultaneously as the most frequently changed part is easy to handle. Another object of the present invention is to provide a rock drilling tool, whose front end of the drill pipe does not have a projection portion and, therefore, no transport damage. The objects of the invention are satisfied by providing a method and a rock drill bit according to the aspects in the characterization portions of the claims. Further advantageous features, according to the invention, will be apparent from the dependent claims. Next, an embodiment of the invention will be described along with the accompanying figures. Figures 1 to 4 show a schematic, partially sectioned view of a rock drilling tool according to the invention. Figure 5 shows the tool in a top view. Figures 6 and 7 show cross sections of the ends of the alternative female threads. The rock drilling tool 10 as shown in the figures, comprises a rock drill bit 11 and a drill pipe 12. The drill 11 has a head 13 provided with a front surface 14, from which a number of front inserts 15 project, and a peripheral row of peripheral inserts 16. , preferably provided with spherical or ballistic work surfaces. The drill bit is provided with a male thread 7, which is provided to cooperate with a female thread 18 on the tube.

The male thread 17, which is provided on a tang 19, is an integral part of the percussion drill bit 11. The drill bit is provided with a shoulder at the inner end of the tang 19, such shoulder has a surface of flat stop 21 facing the free end of the peg 19. The stop surface 21 extends perpendicularly relative to a longitudinal central axis 22 with the drilling tool 10. The weight of the head 13, including the inserts, is a maximum of 2.5 times, preferably less than 2 times the weight of the pin 19 when the parts are separated in the shoulder 20. The free end of the drill pipe 12 has the shape of a hollow, flat end surface 23, which it extends perpendicularly relative to the central axis 22. The threaded connection further comprises a female thread 18, which is formed in the drill pipe as an integral part thereof. The bottom shape of the female thread, in most cases, is adapted to provide optimum resistance for the tube as shown in Figure 6. Alternatively, as seen in FIG.

Figure 7, for example, the bottom of the female thread, can have the shape of a flat surface,, which extends perpendicularly with respect to the central axis 22 in the bottom of the box, which is beneficial.

In the latter case, the distances between the shoulder stop and the surface 24, and the end surface 26 of the spike, respectively, so that the latter are in contact or reach back contact as the tool is used, so that the area of the bit for directed straight energy is increased . In most cases, it is advantageous to provide tapping openings 27 and 28 together with the shoulder stop, to level the bending forces and to avoid the stop in that area in parts 12 and 19. The threads 1 7, 18 They can be cylindrical wire threads or cylindrical trapezoidal threads and have a pitch angle of approximately 5-15"I. He Rock Drilling Hep 10 has a central fast-flow channel, which is divided into at least other two channels in the head, it is evident, from the figures, that the abutment surface 21 of the drill bit in an active position, it is always activated against the flat end surface 23, on the free extr e of the tube, which means that the shoulder stop is established. Figure 4 schematically shows a rock drilling tool according to the present invention, wherein the axial length of the shoulder 20 towards the free end of the shank is L1 and the height of the drill 11 between the shoulder 20 and the front surface 14 is L2. The extreme diameter of perforation 12 and shoulder 20 is designated D1 and the smallest external diameter of the pin is designated D2, which is approximately equal to the smallest diameter of the female thread. The larger diameter of the head 13 is designated D3, which is preferably equal to, or slightly less than the diameter of the outer circle touching the peripheral inserts 16. The ratio of D3 / D1 is preferably greater than 1. , and preferably less than 1.5. The outermost part of the shoulder 20 describes, according to Figure 5, a circle having a diameter D1 and forming a cylinder 25, which crosses the peripheral inserts 16 substantially in the middle part or close to its active working surfaces. . The latter forces the percussive energy towards where it is most useful, that is, the impact wave can travel straight to the insert without any energy-consuming deflection. The drill pipe 12, in this way has a substantially constant external diameter D1 and axial length L2 of the head, is provided shorter than the axial length L1 of the pin. The percussion energy is transferred substantially straight from the drilling tube to the contact tubes with the drill hole through inserts 16, presenting an imaginary cylinder 25, being in an extension of the external diameter Ü1 of the shoulder intersecting with the peripheral inserts 16. The present invention in this manner is characterized by the combination of shoulder stop with a short head and straight energy which is transferred to a rock drilling tool.

Claims (10)

REVINDICACJpNES

1. A method for transferring the percussion energy of a percussion drilling tool into a hole, wherein the tool comprises a drill pipe and a drill bit cooperating through at least one shoulder stop in a threaded connection, the connection comprises at least one cylindrical male thread and a cylindrical female thread, the male thread is provided on a pin which is an integral part of the drill bit, the drill bit is provided with a stop surface facing the The free end of the spigot, the female thread is provided in the drill pipe and the free end of the drill pipe is provided with an impact surface, characterized in that the drill pipe is provided with a substantially constant external diameter and the axial length of the head is shorter than the axial length of the spike and that the percussion energy is transferred substantially A straight form from the drill tube to points of contact with a hole through inserts having an imaginary cylinder, being in an extension of the outer diameter of the shoulder intersecting the peripheral inserts provided in the head.

2. The rock drilling tool for percussion drilling comprising a drill bit and a drill pipe, which cooperate through at least one shoulder stop in a threaded connection, the connection comprises at least one male thread and A hem rna the r sca male e < The drill bit is provided with a shoulder at the inner end of the spike, the shoulder having a stop surface, facing the free end of the drill bit, provided with a spigot which is integral with the drill bit. the spigot, the female thread, is provided in the drill pipe and the free end of the drill pipe is provided with an impact surface, the threads are cylindrical, characterized in that the drill bit has a head having a front surface, from which a number of front inserts are projected, and the peripheral inserts are arranged in a peripheral row and the drill pipe has a substantially constant external diameter and the axial length of the head is shorter than the axial length of the spike, and an imaginary cylinder that is an extension of the outer diameter of the shoulder intersects the peripheral inserts.

3. The rock drilling tool, according to claim 2, characterized in that the cylinder crosses each insert in or near its outer axial part and the weight of the head is a maximum of 2.5 times, preferably less than twice the weight of the spike.

A. What is the right to a change in the form of conformity with a 2 cm claim? Because the axial length of the head is 0.2 to f ".9 times the axial length of the spike, preferably about 0.5 times the axial length of the spike.

5. I nl l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l l 2, 3 or 4, characterized by the fact that the drill bit is provided with a shoulder at the inner end of the dowel, the shoulder it has a flat stop surface, facing the free end of the pin and the stop surface extends perpendicularly relative to the longitudinal central axis of the drill tool.

6. A drill bit for percussion drilling, characterized in that it comprises a head and a dowel, which have a cylindrical male thread, the dowel is an integral part of the drill bit, the drill bit is provided with a shoulder at the end internal of the spigot, the shoulder has a stop surface facing the free end of the spike, characterized in that a number of front inserts project from a front surface of the head and the peripheral inserts are provided in a peripheral row, and the The axial length of the head is shorter than the axial length of the shank and an imaginary cylinder, the peripheral inserts being an extension of the external diameter of the shoulder.

7. I would like to make a claim with the claim, O? - t "and? < \ mia H cilindj * inte * s otín each insert in, or close to« * «? poi t ^ "^ infu 'nN * more external

8. The rock drilling tool according to claim 6 6 7, cat eete »lighted because the axial length of the head pqf ip) ') or'" • »« &(- "twtttu I 'iv? < | < t •• * o '? íua, «?»?? fe? eucip, ^! l ot fl r < | ()' i wc »<! (il < > t? ilnd? »V« nl ti "H" "[Hu'i

9. I have done the same thing as the "crazy drilling" with the claim 0, 7 • »fl,« • Fii olet r'a or ue * »lp« «? O of the head is a maximum d «» 2 WCPQ, »iofíM urin nienot« 2 VO «; «? P | ple the spike.

10. The lipr rami «» »? Fa d« = > or a photo of confoi idad with any of the lojyjp i'nri? n G 0, cni otri ire that the thread clearance is provided «nti e! (; t »« »7 and the male thread. M HGSUMEN the ipf > e »?» inv n ión "* relates to a drilling tool for a leg, a percussion drill that includes a per-ation drill (II) and your per-wolf worm (12) cooperating Through a PSAPM tee in a threaded connection, the connection comprises at least one in-tp male (W) and one rough female (18) .The male thread (17) et pr vist Robre one is ina (19), which is an integral part of the hole or photon (11). "The photographer is a ptovist with a shoulder (? ()) in the inner part of the spike (19), such a shoulder has a stop surface (21) facing the free end of the spike (19). The horn (18) is provided in the drill pipe (2) and the screw is screwed in. tube d "per fot ation is provided with a surface laugh impact (2). I as toscas (i T, IB) are cylindrical. The present invention is characterized by the combination of the shoulder stop and a transfer nose to the tool or pe * f t tion or? «« > p i. in addition to c refer to i.ti f * h «or a jji» i < < "> • '* in mH flo? -" - > * N? »Sf * M il Jn energy df1 po OU'MOn es» (w »» '(' »'• it« t'-ll 5 of |? < H)' o < ÍM ¡H do t no * -) bf * r »n | (f | quie.}. o.