AU669476B2 - A joining system - Google Patents

Description

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9, OPI DATE 07/09/92 AOJP DATE 15/10/92 APPLN. In 12270 2 q PCT NUMBER PCT/A.192/00044 I INTERN,. 1 TREATY (PCT) (51) International Patent Classification 5 International Publication Number: WO 92/14066 F16B 21/02, 17/00, 7/00 Al E21B 17/04 (43) International Publication Dale: 20 August 1992 (20.08.92) (21) International Application Number: PCT/AU92/00044 (81) Designated States: AT, AT (European patent), AU, BB, BE (European patent), BF (OAPI patent), BG, BJ (OAPI (22) International Filing Date: 6 February 1992 (06.02.92) patent), BR, CA, CF (OAPI patent), CG (OAPI patent), CH, CH (European patent), CI (OAPI patent), CM (OAPI patent), CS, DE, DE (European patent), DK, Priority data: DK (European patent), ES, ES (European patent), FI, PK 4516 7 February 1991 (07.02.91) AU FR (European patent), GA (OAPI patent), GB, GB (European patent), GN (OAPI patent), GR (European patent), HU, IT (European patent), JP, KP, KR, LK, LU, (71) Applicant (for all designated States except US): MINING LU (European patent), MC (European patent), MG, ML CONCEPTS PTY. LIMITED [AU/AU]; Cnr Nicholson (OAPI patent), MN, MR (OAPI patent), MW, NL, NL and High Streets, Toronto, NSW 2283 (European patent), NO, PL, RO, RU, SD, SE, SE (European patent), SN (OAPI patent), TD (OAPI patent), TG (72) Inventor; and (OAPI patent), US.

Inventor/Applicant (for US only) GEATCHES, Darrell, William [AU/AU]; 45 Ilford Avenue, Buttaba, NSW 2288 Published With international search report.

(74) Agent: SPRUSON FERGUSON; G.P.O. Box 3898, Sydney, NSW 2001 (AU).

(54)Title: A JOINING SYSTEM (57) Abstract A joining system is disclosed in which a first member is connectable to a second member Formed within the first member is a female receptacle which includes at least one curved inner surface Extending from the second member (2) is a male protrusion arranged for insertion into the receptacle and includes a first curved outer surface complementing the curved inner surface and a second curved outer surface (10) opposite the first curved outer surface The interengagement of the surfaces and permits a longitudinal connection between the members and with the curvature of the surface (10) permitting ready insertion of the protrusion into the receptacle -1 A JOINING SYSTEM Field of the Invention The present invention relates to a system for joining two members and in particular discloses an arrangement that permits transmission of longitudinal and twisting forces between the members.

Background Art In mining operations, it is commonly required to drill into the face of the mine for the setting of explosive charges and the like. Long bores are drilled using a drill head that is attached via a number of connecting lengths of rod w[;ich return to the drilling machine located in the mine cavity. Typically, the connecting rods are coupled using a screw thread and/or nut arrangement.

However, problems exist with the known arrangement in that through use, and the constant twisting associated with the drilling rods, the screw threads can become jammed and their connection and disengagement can at times be quite difficult and time consuming.

Object and Summary the Invention It is an object of the present invention to substantially overcome, or ameliorate the abovementioned difficulties through provision of a system for joining two members that requires no additional fastening device.

In accordance with the present invention there is disclosed a system for joining a first member and a second member, said system comprising: a female receptacle in said first member having a (first) curved inner surface a radius of curvature of which lies in a plane not parallel to an opening of said female receptacle; and a male protrusion at least connected to and extending from said first curved inner surface, and a second curved outer surface, one of said first and second curved outer surfaces being convex and the other being concave, the concave surface having a radius of curvature substantially the same, but less than that of the convex surface, wherein said second curved outer surface is sufficiently curved so as to permit relative angled insertion of said protrusion into said receptacle for joining said members through substantial longltudlnal alignment of said protrusion within said receptacle; and abutment surface means associated with said protrusion and said 'I receptacle for transmitting compressive forces between said members when joined.

it e~AD/11530 L0 2 Preferably, the members are intended for longitudinal alignment and connection and preferably are connecting rods of a drilling device.

Brief Description of the Drawings Two embodiments of the present invention will now be described with reference to the drawings in which: Fig. 1 is a perspective view of a first embodiment showing the two joining members; Fig. 2 is a perspective view of second embodiment showing the two joining members; Fig. 3 is a transverse cross-section of the two joined members of the second embodiment; and Fig. 4 is a longitudinal end view of the male joining member of Fig. 2.

Referring to Fig. 1, a first member 1 and a second member 2 are shown arranged for longitudinal joining. The members 1 and 2 in this embodiment are of a square cross-sectional shape but can have any cross-sectional shape as determined by the specific application.

The first member 1 includes a female receptacle 3 of substantially cubic shape. The receptacle 3 is distanced from the longitudinal wall faces 4 of the member 1 by an abutment surface 5 arranged at the end of the member 1.

The receptacle 3 includes a curved inner surface 6, eeft€u§v in shape, that extends from the opening of the receptacle 3 adjacent the ~i pabutment surface 5 to a location 15 short of an inner rear wall 7 /l thereof.

The second member 2 includes a substantially elongate male protrusion 8 adapted for insertion into the female receptacTe 3. The protrusion 8 is generally quasi-cubic and substantially corresponds to the inner shape of the receptacle 3. The protrusion 8 includes a first curved outer surface 9, w\in shape'that complements the curved inner j 30 surface 6 of the receptacle 3. The protrusion 8 also includes a second curved surface 10, arranged opposite the first curved surface 9 that permits entry of the protrusion 8 into the receptacle 3. The protrusion 8 is distanced from the longitudinal faces 11 of the member 2 by an abutment surface 12 (illustrated in phantom) that corresponds, and when the members 1 and 2 are joined, abuts with the abutment surface 5 of the first member 1. The protrusion 8 also includes a front face 13 that \12TP IA M)5 3 V^g /.i r -3extends between the curved surfaces 9 and 10 and is adapted to abut the rear wall 7 of the receptacle 3.

The joining of the members 1 and 2 can now be described. The members 1 and 2 are arranged so that the curved surfaces 6 and 9 are adjacent. The leading edge 14 adjacent the front face 13 and curved surface 9, is then, without longitudinal alignment between the members 1 and 2, inserted into the recess 3 to abut the surface 6. The shape of the second curved surface 10 permits full insertion of the protrusion 8 into the receptacle 3 through urging of the surface 10 upon a surface 16 opposite the surface 6 within the receptacle 3. The protrusion 8 is then pushed into the receptacle 3 by sliding the complementary surfaces 6 and 9 across each other. This sliding motion brings the members 1 and 2 Into longitudinal alignment. When fully inserted, the front face 13 abuts the rear wall 7 and the abutment surfaces 5 and 12 are in contact.

This joining arrangement has a number of advantages. Firstly, any longitudinal compression between the members 1 and 2 is absorbed by the abutting surfaces 7 and 13, and 5 and 12. These surfaces define almost all the cross-sectional area of the members 1 and 2, with the exception of that area lost through curved surface 10. Accordingly, the longitudinal compressive strength of the members is not substantially reduced within the join. Also, the join retains much longitudinal tensile strength through friction between the complementary curved surfaces 6 and 9 and the requirement for longitudinal misalignment for Sdisengagement. Also, the arrangement has substantial torsional strength 8.

25 as provdd by the abutting side walls of the receptale 3 and protruion It will be understood by those skilled in the art that the embodiment shown in Fig. 1 can be used for the joining of any two members at any orientation, however, it is much' preferred that the members have 30 preferably a longitudinal alignment when joined.

Further, those skilled in the art will appreciate from their understanding of Fig. 1 that a radius of curvature of the the curved surface 6 lies in a plane perpendicular to, and therefore not parallel to, a plane in which the opening of the receptacle 3 lies, which in Fig.

1, includes the abutment surface The embodiment shown in Figs. 2, 3 and 4 is specifically adapted for drilling operations in mines.

i/1153o -e -4- Fig. 2 shows a male connecting piece 20 of a drilling connecting rod 21 and a female connecting piece 23 of a rod 22. The rods 21,22 are of hexagonal longitudinal cross-section as better seen in Fig. 4 and include a feedwater line or air passage 22 passing along their longitudinal axis for the supply of cooling and flushing feedwater or air to a drilling bit (not illustrated).

As better seen in Fig. 3, the connecting pieces 20 and 23 are joined to their respective rods 21 and 22 at recesses 40,39 formed therebetween, by threaded connections 38 and 37 respectively. This permits ease of manufacture of the rods 21,22 and pieces 20,23 separately, whilst also permitting ease of maintenance through the replacement of broken or damaged connection,. Alternatively, the connecting pieces 20,23 can be integrally formed with their respective rods 21,22. Also, welded connections can be used, particularly to increase the strength of the threaded connections 37,38. Generally a single connecting rod has a male connecting piece 20 at one end and a female connecting piece 23 at the other.

Returning to Fig. 2, the male connecting piece 20 is formed with a hexagonally shaped abutment surface 35 from the centre of which extends a elongate male protrusion 50 having opposite curved outer surfaces 26 and 34. The protrusion 50 substantially corresponds in shape to an extent to the hexagonal shape of the rod 21 of which two side faces 30 and 31, .adjacent the curved surface 26, correspond. The curved surface 34, at the surface 35, substantially corresponds to a portion of a hexagon, but, ,i 25 as it extends towards a front face 32 of the protrusion 50, the surface 34 obtains a bell-shaped profile. This is best seen in Fig: 4. This shaping acts to increase the contact surface area between the pieces and 23 when joined.

The male connecting piece 20 has a'channel or bore 41 which aligns 30 with the feedwater line 22 of the rod 21 at the connection 38. The channel 41 extends, substantially centrally through the connecting piece and ends in an aperture 42, seen in Fig. 2. In view of the shape of the front face 32 and the desirability of locating the aperture 42 centrally on the face 20, the channel 41 is slightly inclined, when compared with the feedwater line 22, as best seen In Fig. 3.

The female connecting piece 23 includes a surface 36 arranged to abut with the surface 35. A receptacle 27 is provided to receive the I 3 5 male protrusion 50 of the piece 20 and has a curved convex inner surface configured to meet the concave surface 26.

Unlike the first embodiment, the receptacle 27 Includes an additional curved inner surface 33 which is configured to meet the surface 34, thereby increasing contact between the two pieces 20 and 23 as alluded to above.

The receptacle 27 has a rear wall 28 of shape similar to the front face 32 but of slightly larger size about the curved surface 33. This creates a small vacant space 43, seen in Fig. 3, which provides for ease of insertion and extraction, in the same manner as the first embodiment, of the piece 20 into and out of the piece 23.

So as to permit the communication of feedwater between the pieces 20,23, the female connecting piece 23 has a water channel or bore 44 configured to meet with the aperture 42. The channel 44, like to channel 41 is also inclined, so as to meet with the feedwater line 22 of the rod 24. A rubber grommet 45, seen in Fig. 2, provides sealing between the pieces 20 and 23 and is arranged to be seated within a suitably shaped recess 46, which defines an aperture, at the end of the channel 44.

On insertion of the protrusion 50 into the receptacle 27, the front face 32 engages the grommet 45, forcing it into the recess 46 such that the face 32 also engages the rear wall.

In a similar manner, annular washers (not illustrated) can also be used to ensure a water tight seal at the threaded connections 37 and 38.

The foregoing describes only two embodiments of the present inventions and modifications, obvious to those skilled in the art can be made thereto without departing from the scope of the present invention.

For example, it is apparent that the curved surface 6 can be concave in shape provided the surfaces 9 and 10 on the protrusion 8 are appropriately transformed.

Industrial Applicability The present invention is 6seful in joining rods and like members and particularly use in mining and drilling operations.

I

Claims (14)

1. A system for joining a first member and a second member, said system comprising: a female receptacle in said first member having a (first) curved inner surface a radius of curvature of which lies in a plane not parallel to an opening of said female receptacle; and a male protrusion at least connected to and extending from said second member and having a first curved outer surface complementing said first curved inner surface, and a second curved outer surface, one of said first and second curved outer surfaces being convex and the other being concave, the concave surface having a radius of curvature substantially the same, but less than that of the convex surface, wherein said second curved outer surface is sufficiently curved so as to permit relative angled insertion of said protrusion into said receptacle for joining said members through substantial longitudinal alignment of said protrusion within said receptacle; and abutment surface means associated with said protrusion and said receptacle for transmitting compressive forces between said members when joined.

2. A system as claimed in claim 1, wherein said plane is at least substantially perpendicular to the opening of said female receptacle.

3. A system as claimed in claim 1 or 2, wherein said plane is perpendicular to the opening of said female receptacle.

4. A system as claimed in claim 1, 2 or 3, wherein upon said angled insertion of said protrusion into said receptacle, said first curved outer surface engages and slides across said first curved inner surface wherein the engagement between said receptacle and said second curved outer surface urges said first curved outer surface towards said first curved inner surface and into substantial longitudinal alignment therewith.. A system as claimed in claim 4, wherein said receptacle has a second curved inner surface opposite said first curved inner surface, and curved in a manner substantially complementary to said second curved outer surface. i tt I A t 7

6. A system as claimed in any one of the preceding claims, wherein said male protrusion is unitarily formed in said second member.

7. A system as claimed in any one of the preceding claims wherein said abutment surface means comprises a first abutment surface formed on said second member adjacent said protrusion and configured to engage a corresponding second abutment surface of said first member adjacent said receptacle when said members are joined.

8. A system as claimed in claim 7 wherein said first and said second abutment surfaces each surround said protrusion and said receptacle respectively.

9. A system as claimed in any one of the preceding claims, wherein said abutment surface means (further) comprises a face forming a free end of said protrusion arranged to abut a rear wall of said receptacle. A system as claimed in any one of the preceding claims, wherein each of said members includes a bore passing therethrough and adapted to permit fluid communication through said first member to said second member, or vice versa, when said members are joined.

11. A system as claimed in claim 10, wherein said fluid is selected from the group consisting of water and air.

12. A system as claimed in claim 10 or 11, wherein said bore of said first member ends with a first aperture opening into said receptacle, and said bore of said second member ends with a second aperture at said protrusion, said apertures having corresponding alignment locations upon joining of said members.

13. A system as claimed in claim 12, wherein said first aperture is formed in a rear wall of said receptacle and said second aperture is formed at the free end of said protrusion.

14. A system as claimed in claim 13, wherein said first aperture includes a recess thereabout within which a sealing means can be positioned for compression between said rear wall and said peripheral face upon joining of said members to seal the Interconnection of said bores. A system as claimed in any one of the preceding claims, wherein said receptacle is an elongate socket having a polygonal 0 NA] -8- transverse cross-section, and said first curved inner surface forms at least one longitudinal surface of said socket.

16. A system as claimed in claim 15, wherein said socket has a rectangular cross-section

517. A system as claimed in claim 16, wherein said socket has a square cross-section. 18. A system as claimed in claim 15, wherein said socket has a substantially hexagonal cross-section. 19. A system as claimed in claim 18, wherein said second curved surface of said protrusion has a substantially bell-shaped cross-section at a portion of the protrusion toward a front face of the protrusion, complementing two adjacent surfaces A system as claimed in any one of the preceding 'claims, wherein interengagement between said receptacle and said protrusion to join said members is permits the transmission of rotational torque forces between said members, whereby doll rotation of one said memnber causes corresponding rotation of the other said member, without causing disengagement of said members. interengagement between said receptacle and said protrusion to join said members pristhe transmission of comnpressive and tensile forces between said members. to22. A sys .,T1 as claimed in any one of the preceding claims, wherein the joining and dis-joining of said members is achieved by angular displace~ment of one said member relative to the other in one direction and in one plane only relative to a longitudinal centreline of said members when joined. 434 25 23. A system as claimed in claim 22, wherein said first curved inner and loll Iouter surfaces are struck from a common centre -that lies external to said members when joined. 24. Apparatus comprising at least one of said first member being capable of being joined with said second member, said members as defined by the system. of any one of the preceding claims. Apparatus comprising at least one of said second member having a male protrusion as defined by the system of any one of the preceding claims. 26. A connecting device incorporating the system as claimed in rN:\LIBooJooal 2:IAD 9- -9- any one of the preceding claims, and being provided for joining with another like connecting device, each said connecting device comprising a main body having arranged thereon at least one said first member and at least one said second member. 27. A connecting device as claimed in claim 26, wherein said body is an elongate rod and said first and second members are arranged at opposite ends of said rod. 28. A connecting device as claimed in claim 27, wherein said protrusion and receptacle on said rod are longitudinally aligned to permit joining of said connecting device to at least one other like connecting device. 29. A connecting device as claimed in claim 27 or 28, wherein a said rod and said first and second members have a bore passing therethrough. A system for joining a first member and a second member, said system being substantially as described herein with reference to Fig. 1, or Figs. 2, 3 and 4 of the drawings. i DATED this THIRD day of APRIL 1996 Mining Concepts Pty Limited Patent Attorneys for the Applicant SPRUSON FERGUSON 17 ri A In