JPS59141687A - Apparatus for connecting drill member - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION In the field of drilling equipment, drilling equipment includes drills, such as rotary impact drills, supported by an extension boom or mast and power supply means for longitudinal controlled movement. It is generally put into practical use.

Extended drill chain with chisel attached to the cutting edge (
A drill drill (drill etrig) extends longitudinally of the mast and is operatively connected to the drill motor to provide impact drilling action or a combined impact and rotational drilling action to force the formation longitudinally. When it is done, it is transmitted to the drill train.

In practice, the limitations on the movement of the drill motor along the mast often do not meet the desired hole depth. , KJ:F) can be completed by adding many pieces.

Many drill member connection systems have been disclosed in the art. As an example shown in the figures, U.S. Pat. and discloses an extension drill part intended to be secured to the cooperating end of a drill member which also has a thread, by means of an internally threaded connecting member shown in FIG. 1 of that patent. are doing.

FIG. 4 of the same patent shows that the two drill members are completely fixed.
a pair of coupled drill bits having an internally threaded portion, an fc end, a threaded portion and a non-threaded portion on the inner periphery, engageable by a suitable connecting member having an externally threaded portion; Parts are shown.

U.S. Pat. No. 3,424,479 discloses a drill member having a circumferential thread extending substantially along its entire axial length. U.S. Pat. No. 3,567,254 states:
A drill member having alternating threaded portions and non-threaded portions on its outer periphery, wherein the threaded portion adjacent to one end of the drill member is engageable with a connecting member having a threaded portion therein to fully secure the drill member. is disclosed. The non-threaded part of the drill member is
It includes a collar that cooperates with the fitting to prevent movement of the connected drill member in either direction along the threaded end. U.S. Patent No. 3.822. No. 752 and the above-mentioned patents, the drill members and connection systems recycle drill members by replacing worn threads adjacent the ends of the drill members with new threads adjacent the worn parts. It is possible to cut as much as possible.

It is well known in the art to provide conventional drill members with stress relief means to reduce the occurrence of fatigue defects and stress build-up within the drill member structure. For example, U.S. Patent fJ 3.966,341 discloses a threaded end full-stage drill member suitable for engagement with a fitting that connects a pair of drill members end-to-end. There is. The stress relief means are provided adjacent the threaded end of the drill member and include axially adjacent annular cuts or grooves as shown.

The present invention relates to improvements to known drill members and connection systems such as those described above, including, but not limited to, drill members having fully axially extending threads for engagement with the connection member and stress relief. The means includes an axially extending stress relief section disposed axially concentrically with respect to the threaded portion of the drill member.

In a preferred embodiment of the invention, the cylindrical drill member has an internally threaded portion extending over substantially its entire length, such that the externally threaded fitting has a Cooperatively stroking the internal threads to secure the pair of drill members end to end. If the threads are damaged, the affected drill member end can be cut to provide a new thread for engagement with the connecting member.

It is an object of the present invention to provide an improved drill member for drilling holes.

Another object of the invention is to provide an improved overall connection system for drill members.

Yet another object of the invention is to provide a complete drill member including axially concentric connection engagement means and stress relief means.

Hereinafter, the present invention will be explained in more detail based on the embodiments shown in the drawings.

1 to 4, the longitudinal extension of the drill part paulownia according to a preferred embodiment of the present invention is shown at 10.
is shown. The drill member 10 is formed of any suitable material, such as hardened steel, and has an inner peripheral surface 1 as shown in the figure.
2 and an outer circumferential surface 14. In the following description only one end of the drill member will be referred to, but the description should generally apply to both longitudinal ends of all drill members according to the invention.

The inner circumferential surface 12 extends from one shaft end 18 of the drill member 1o to the notch 2o, such as a rope screw 16 having a length L that is about 2 to 3 times the root diameter of the screw 16, that is, the root diameter of the screw 16. Proper force bearing screws are formed. The screw 16 is a single-thread screw or a double-thread screw when desired, and the length of the screw 16 is determined by the length required for engagement with a suitable drill member connector (described later) or as shown in FIG. XL is several times the engagement length. Alternatively, the drill member 1o does not have a notch 20'z (FIG. 3), but instead has an internal thread 16 which is continuous from one shaft end 18 to the other.

The notch 20 provides a convenient thread termination for easily controlling the length of the thread during the thread forming process. If sufficient precision control is implemented over the thread forming process by techniques such as periodic control or numerical control, thread termination at a precise point can be achieved without resorting to the use of the notch 20. This is achievable and the thread forming process is of sufficient accuracy.

The inner circumferential thread 16 can also be formed by a forge welding molding method in which the drill member 10 is molded with a threaded mandrel (not shown). If the shoulder portion of the notch 20 has a diameter smaller than that of the connecting member, it may be possible to completely suppress the movement of the connecting member in the axial direction, as will be described later.

1-3, a plurality of successive stress relief means of axially spaced circumferential grooves 22 on the outer periphery 14 of the drill member 10 are shown. In the case of the configuration shown in FIGS. 1 and 2, the outer circumferential groove 22 is preferably threaded by a length of about 1)/2 from the shaft end 18 of the drill member 10, where the root diameter fD of the screw 16 is It forms a concentric structure with the screw 16 over a point 24 beyond the terminal end of i6.

One purpose of providing the stress relief groove 22 beyond the relief of the screw 16 is to minimize the effect of the notch 20 as a stress riser.

As can be seen in FIG. 3, in the case of a drill member 10 having an internal thread 16 continuous from one shaft end I8 to the other, a plurality of continuous external grooves 22 also extend from the other end 18 to the other end. are arranged continuously.

As shown in FIG. 4, in another embodiment of the inventive stress relief means, a helical groove 26 is provided along the outer periphery 14 of the drill member 10 over a liquid permeable length as described above.
Stress relief is achieved by The helical groove 26 may be a single groove or, if desired, a multiple groove. For the embodiment of FIGS. 1 and 2, the helical stress relief groove may taper toward the outer diameter of the drill member or terminate at a non-visible end. The depth of the troughs of the outer circumferential grooves 22 or 26 is set to be deeper than the surface damage that would normally be applied to a convex portion 28 of a full outer diameter located between adjacent grooves 22 or between turns of the helical groove 26. at least 0.254 ran,
(0,01 inch). Of course, the stress relief grooves 22 and 26 should have a diameter of 1.27 to 2.54 mm (0,0
(5 to 0.1 inches) or deeper as necessary or desired.

Stress relief grooves 22 provide a large number of stress relief channels distributed axially along the length of drill member 10 to distribute stress concentrations along the drill member. Furthermore, since stress concentration occurs in the groove 22 which is protected from physical damage by the intervening protrusion 28 having a perfect outer diameter, the intervening protrusion 2g is exposed. Any damage to the outer surface that would result from impact with rock debris in contact with the wall of the hole does not result in significant stress increases. Spiral groove 2
It goes without saying that the function of No. 6 is also similar.

Referring to all of FIGS. 5 to 7, the above-mentioned drill member 1
Several embodiments of fittings are shown for coupling all 0 to one another. Each fitting 30 for the drill member 10 is
It includes a peripherally threaded extension member 31 having an axial bore 32 . The outer circumferential thread 34 of the fitting 30 cooperates to threadably engage the inner circumferential thread 16 of the drill member 10.

In FIG. 5, the length of the connecting tool 31 is slightly shorter than the distance between the shoulders 36 in the notches 20 of the two drill members 10 whose ends are in contact with each other. This forces the fitting to continue between the shoulders and restrain it against axial movement when the drill member 10 is screwed into the fitting 30. In this construction, the ends 18 of the drill members directly abut each other and drill impact forces are transmitted from one drill member to the next through a single boundary. Drill fluid flows through the axial bore 32 of the cylindrical drill member 10 or fitting 30 for the purpose of cooling the drill bit and cleaning the borehole, as is well known.

In FIGS. 6 and 7, the drill members 10 to be connected are threaded over the entire distance XL or continuously as described above, so that if the connection loosens, the drill members 10 in FIG. A fitting 30 as shown would be free to move out of the joint. Therefore, in the center of both threaded ends, the connection device designated 30' in FIG. It includes an annular projection 38 of increased diameter to form abutting, opposing shoulders 40. The shoulder secures the fitting 30' axially with respect to the drill member 10 and prevents its movement. This structure is not an optimal arrangement since the drill impact force is transmitted through two abutment boundaries in each fitting. A better means of achieving this is shown in FIG. 7, where the fitting 30'' includes an enlarged diameter annular projection 42 formed on the fitting 30'' at the center of each threaded end. The diameter of the protrusion 42 is substantially smaller than the outer diameter of the drill member 10 and each drill member 10 has an inner annular groove 44 formed adjacent each shaft end 18 such that the drill member 10 connects. When screwed into the tool 30'', the shaft ends 18 of the drill members directly abut each other and drill impact forces are transmitted from one drill member to the other in a single mechanical boundary. Articulation. An annular groove 44 formed in the adjacent end of the drilled drill member 10 forms a notch 45 that forces and surrounds the annular projection 42 of the fitting 30'' to prevent movement of the fitting.

In another embodiment, shown in FIG. 8, the fitting 30'' has an annular conical portion 52 of increased diameter formed outwardly of the fitting 30'' in the center of each threaded end.
All included. The outer diameter of the conical portion 52 is the same as that of the drill member 10.
each drill member 10 has an internal chamber 54 formed therein adjacent each shaft end 18 so that when the drill member is threaded into the fitting 30'', the adjacent drill The axial ends of the members directly abut each other and the drill impact force is transmitted from one drill member to the other through the mechanical interface of the nest.The internal chambers formed in the adjacent ends of the drill members are , to prevent movement of the connector, the connector 30"'
A notch 55 is formed which surrounds and forcibly maintains the conical part of. An advantage of the embodiment shown in FIG. 8 is that the internal chamber 54 is relatively easy to form in the drill member initially or in the event of a rond failure.

The advantages of the drill members and fittings described above are manifold. In order to perform efficient and economical drilling operations, those in the art have sought inexpensive ways to quickly and easily refurbish the ends of broken or damaged drill bits for reuse. The embodiment of FIGS. 2 and 3 provides that if the threads engaged with the fitting are damaged, the damaged threads can be quickly severed and the end of the drill member can be replaced with a new thread. and is finished to permit continued use of the drill member. By locating the entire threaded part inside the cylindrical drill member, the possibility of damage to the threaded part is minimized. It is partially derived. An additional advantage arises from the stress relief means provided concentrically on the connecting engagement portion of the drill member. In this connection, the stress relief means described above may be of other constructions than radial or helical grooves, and may also be of coextensive construction with respect to the shape of the connecting engagement means other than screws. Good things are important. For example, would the stress relief means described above provide similar advantages to those mentioned in connection with screws, even if the connection means were replaced by less conventional structures such as taper fits or bayonet fits? provide.

Another advantage of note is that the internal passages of the cylindrical drill member constitute an air or fluid flow path for removing debris from the bottom of the borehole and for total cooling of the drill bit. be. The through holes of the fittings are necessarily of limited diameter, resulting in reduced flow rates compared to those available with conventional externally joined drill members. However, the reduced flow rate is efficient for the following reasons. At a given air or fluid pressure, the available air or fluid flow rate is limited more noticeably by the cross-sectional area of the connecting hole. Since the improved drill chain is supported entirely inside the connecting tool, the outer diameter of the drill chain is limited by the outer diameter of the connecting tool being the limiting factor for the diameter of the drilled hole, and the majority of the drill chain is Fills the borehole more completely than in conventional drill chain systems where the diameter of the borehole is smaller than the diameter of the borehole. Therefore, in the present invention, the annular space between the drill member and the borehole wall is smaller and more uniform than in conventional drill trains, which allows for a better flow rate for a given flow rate inside the drill train. High air or fluid flow rates are provided. The present invention improves the overall debris removal rate at a given air or fluid pressure, since a higher flow rate more effectively removes debris from the borehole.

Another advantage of the present invention is that the stiffness of the tubular drill member is improved compared to conventional drill members. Stiffer drill members tend to drill holes that are straighter and more perfectly round. Additionally, the drill shock wave is transmitted along the cylindrical drill member to the outer circumference of the drill bit. It is believed that this provides a more efficient drilling action than the transmission of pressure waves to the center of the drill bit, since if the cylindrical drill member is rigid, the drill member will hardly flex under the supply pressure. , the energy transmission along the drill member becomes more effective.

According to the present invention, a cylindrical structure having a connecting engagement means such as a lobe screw on its inner peripheral surface, a stress relief means provided on the outer periphery of a drill member, and a similar spatial arrangement are provided. An improved drill member for impact double-hole drilling is provided, the entire drill member including an engagement means and an entire drill member. It is desirable that the stress relief means extend further along the trill member than the area of the threaded portion on the inner periphery.

The threads on the inner circumference of the drill member are provided over a distance greater than the length of the threaded engagement portion for the connection to be used, so that threads near the end of the drill member are used. The ends can be easily cut and finished to provide an obviously unused threaded part, allowing the drill member to be fully reused even if damaged.

It is in no way intended to be limited to the particular embodiments described above, and the inventors believe that the invention is capable of other configurations within wide design tolerances without departing from its broader spirit. I fully believe in one thing. For example, the specific methods and proportions described above may be subject to considerable modification, and the specific cross-sectional shapes of the stress relief grooves illustrated may be modified in a variety of ways as long as dangerous stress build-ups do not occur. , the central protrusion of the fitting can be replaced by a radially projecting lug or other shapes that do not all have a continuous annulus of uniform diameter, etc. In addition, concentric stress relief means and drill member connection threads may alternatively be used in constructions using integral bottle and cylindrical threaded fittings for other connection systems that do not require a single coupling element at all. 'It is Noh.

These and other embodiments and modifications are intended and contemplated by the inventors, and claims of non-invention should be interpreted as broadly as permitted by the appended claims.

[Brief explanation of drawings]

FIG. 1 is a longitudinal partial cross-sectional view of a drill member constructed in accordance with a preferred embodiment of the invention; FIG. 2 is a longitudinal section similar to FIG. 1 showing another embodiment of the invention; 3 is a partially cutaway side view showing all other embodiments of the present invention; FIG. 4 is a sectional view showing an embodiment of the stress relief means according to the present invention;
A partial side view similar to FIG. 3, FIG. 5 is a vertical sectional view of the method of connecting the pair of drill members in the embodiment shown in FIG. 1, and FIG. 6 is a longitudinal sectional view of the drill member in the embodiment shown in FIGS. 2 and 3. FIG. 7 is a longitudinal section similar to FIG. 5 showing one means for coupling the pairs; FIG. 8 is a 1-longitudinal sectional view showing another means for connecting the drill parts of the embodiment of FIGS. 2 and 3; FIG. 10・・・・・・・・・・・・・・・・・・・・・ Drill member 12・・・・・・・・・・・・・・・・・・
・Inner circumference threaded part 22・・・・・・・・・・・・・・・・・・
・・・Stress relief groove 20・・・・・・・・・・・・・・・
・・・・・・Notch part 31・・・・・・・・・・・・・・・
・・・・・・Connection tool 38・・・・・・・・・・・・・・・
......Large diameter section 32...
・・・・・・General Applicant Joy Manufacturing Company Representative Patent Attorney Tadashi Yonehara
Akira Patent Attorney Ko Matsumoto Procedural Amendment (-, Type 5) Showa, March 9, 1959 Commissioner of the Patent Office Kazuo Wakasugi Tono 1 Indication of the case Patent Application No. 180068 1982 2 Title of the invention Drill member coupling device 3, Person making the amendment: February 8, 1980 (Delivery date: February 28, 1982)
6. Correction Nu'I Elephant-466-=

Claims (23)

[Claims] (1) for use in forming an extended drill chain which includes, adjacent to at least one shaft end, connecting means for connecting a drill member end-to-end to another drill wing; The drill member is characterized in that the drill member has stress relief means arranged longitudinally and concentrically over at least a large portion of the fitting in the longitudinal direction. Drill member joining device. (2) Claim 1, characterized in that the drill member is generally cylindrical and the connecting means includes integrally formed means axially disposed inside the drill member. ) The drill member joining device described in item 2. 3. A drill member coupling device according to claim 2, wherein the stress relief means comprises integrally formed means on the outside of the drill member. (4) The trill member coupling device according to claim (1), wherein the connecting means includes a threaded portion. (5) The drill member coupling device according to claim (4), wherein the stress relief means includes a series of nine annular rings spaced apart in the axial direction. (6) The drill member coupling device according to claim (4), wherein the stress relief means includes a spiral groove. (7) The length of the threaded portion of the drill member in the axial direction is greater than the length of the threaded portion necessary to completely connect the drill member to another drill member. The drill member coupling device according to item 5) or item (6). (8) The longitudinal length of the threaded portion is at least twice the length of the threaded portion necessary to fully connect the drill member to another drill member. No. (
7) The drill member joining device according to item 7). (9) The stress relief means has a length in the vertical direction along the drill member which is larger than the length in the vertical direction of the threaded portion;
A drill member coupling device according to claim 8, characterized in that it has all its features. (10) The stress relieving means has a length in the vertical direction along the drill member that is larger than the length in the vertical direction of the threaded part by about 1/2 of the root diameter of the threaded part. A drill member coupling device according to claim (9). (11) Claim No. 10, characterized in that the drill member is generally cylindrical, and the stress relief means and the threaded portion are arranged on the outside and inside of the drill member, respectively.
).The drill member joining device described in ). (12) the groove is at least 0.0 mm smaller than the complete outside diameter of the drill member;
．． The drill member coupling device according to claim 5 or 6, characterized in that the drill member coupling device has a depth of 254 mm. (13) The groove is 0.254 mm larger than the complete outer diameter of the drill member.
Drill member coupling device according to claim 12, characterized in that it has a depth in the range from mm to 2.54 ran. (14) A patent characterized in that the connecting means has at least a connecting portion adjacent to one axial end of the drill member and a connecting member cooperating with said connecting portion to connect the drill member to another drill member. A drill member coupling device according to claim (2). (15) Claim 1, characterized in that the drill member includes means for cooperating with other connected drill members to prevent axial movement of the connecting member.
4) The drill member joining device according to item 4). (16) The drill member coupling device according to claim (15), wherein the means for preventing movement in the axial direction includes a notch formed on the inner periphery of the drill member. . (17) The drill member coupling device according to claim (15), wherein the means for preventing axial movement includes a large diameter portion formed in the connecting member. (18) Claim No. (17) characterized in that the drill member is brought into contact with the large diameter portion in the axial direction.
) The drill member joining device described in item 2. (19) The drill member includes means for axially abutting the connected drill member and for capturing and maintaining the large diameter portion to prevent the connecting member from moving in the axial direction. A drill member coupling device according to claim (17). (20) A drill member having a generally cylindrical extension portion located adjacent to one shaft end, and having an inner circumferential surface and an outer circumferential surface, the drill member having the inner circumferential surface or the outer circumferential surface. a connecting engagement means formed on one of the outer circumferential surfaces and extending in the axial direction toward the cylindrical portion; and a stress relieving means formed on the other of the inner circumferential surface or the outer circumferential surface; means extending axially into said tubular portion and disposed axially concentrically with respect to at least a major portion of said connecting and engaging means; Drill member joining device for forming a twist-extension drill chain by selectively connecting the ends (21) The drill member coupling device according to claim 20, wherein the stress relief means is arranged concentrically with at least the connection means. (22) The stress relief means extends longitudinally into the cylindrical portion from one axial end of the drill member, and the connecting engagement means extends longitudinally into the cylindrical portion from the one axial end. Drill member coupling device according to claim 2I, characterized in that the device is arranged concentrically with respect to at least the longitudinal extent of the stress relief means. (23) The drill member coupling device 0 according to claim 22, wherein the stress relief means includes an annular groove and the connection engagement means includes a threaded portion.