Double end fastener

Abstract

This disclosure relates to a double end fastener where one end of the fastener is secured, or fastened, to a surface, such as a rock face, concrete, or masonry surface, and an alternate, or opposite, end of the fastener is exposed from the surface. The fastener being particularly suitable for use in the construction and mining industries, where a fixture might be releasably attached to the alternate, or opposite, end of the fastener that enables the fastener to be "pull tested" to determine the SWL of the fastener and / or ensure adequate securement of the fastener to the surface.

Description

DOUBLE END FASTENERPRIORITY DOCUMENTS

[0001] The present application claims priority from Australian Provisional Patent Application No. 2024900260 titled “DOUBLE END FASTENER” and filed on 5 February 2024, the content of which is hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates to a double end fastener. For the purpose of explanation, the present disclosure relates to fastening or securing one end of a fastener to a surface, such as a rock face, concrete, or masonry surface, and having an alternate end of the fastener exposed from the surface, however its application is not so limited.BACKGROUND

[0003] Rock or masonry fasteners have widespread applications in mining and construction industries. In many of these applications, it is advantageous to apply a confining force to the rock or masonry being supported to supress the growth of microcracks in the rock or masonry. Confining force is typically applied by tensioning up a nut on an exposed threaded section of the fastener.

[0004] In an underground environment, fasteners are typically installed in a borehole drilled into a rock face. The fastener is anchored in place by some form of mechanical friction, in one example a section of the fastener is against the internal surface of the borehole to create friction, alternatively, in another example, the fastener may be anchored in place by using a cement-based grout or a chemical resin which cures and hardens to secure the fastener within the borehole. Once the fastener is installed, it is often “pull tested” to ensure the fastener is anchored to the correct Safe Working Load (SWL) and has achieved the desired strength.

[0005] In the mining industry, heavy-duty fasteners are generally used for their higher rated SWLs, and accordingly require installation by equivalently heavy-duty machinery such as a hydraulic (or high voltage) jumbo drill (also referred to as hydraulic bolting jumbo), or a pneumatic underground rock drill. These heavy-duty machines require users with specialised training to operate them and are often limited in availability on a site due to their high cost. However, there are many applications where light to medium SWLs are sufficient, and where a fastener may only require temporary installation (i.e. may be subsequently removed). In these light to medium use cases, heavy-duty fasteners are currently still utilised, requiring access to and the use of heavy-duty machinery and adequately trained operators toutilise them. Presently available fasteners for the mining industry are also often specifically designed for use with heavy-duty machinery and are thereby often limited in their application and use.

[0006] It is against this background and the problems and difficulties associated therewith, that the present invention has been developed.SUMMARY

[0007] According to a first aspect of the present disclosure, there is provided a double end fastener comprising: an elongated body comprising, a leading end comprising a first screw-thread adapted to screw into a surface, a trailing end comprising a second screw-thread and a drive socket, and at least one passageway extending along at least a portion of the elongated body; wherein, in use, rotation applied to the drive socket enables the first screw-thread to be screwed into the surface and the at least one passageway permits flow of an adhesive into the surface, whereby the adhesive aids in securing the leading end of the fastener to the surface.

[0008] In one embodiment, the at least one passageway extends along at least a portion of the leading end toward a periphery thereof.

[0009] In one embodiment, the at least one passageway is a channel extending through the first screw- thread of the leading end toward a periphery thereof.

[0010] In one embodiment, in use, the channel guides flow of the adhesive to the periphery of the leading end such that the adhesive is applied along the first screw-thread and at the periphery of the leading end to effectively aid in securing the leading end of the fastener to the surface.

[0011] In one embodiment, the adhesive is a grout or chemical additive that aids in securing the leading end of the fastener to the surface.

[0012] In one embodiment, the adhesive is a grout or chemical additive that aids in securing the leading end of the fastener to the surface, wherein in use, the grout or chemical additive creates a bond between the leading end of the fastener and the surface.

[0013] In one embodiment, in use, the adhesive is a grout or chemical additive that creates a bond between the first screw thread of the fastener and the surface.

[0014] In one embodiment, the double end fastener further comprises a fixture that is releasably attachable to the second screw-thread.

[0015] In one embodiment, in use, the fixture enables the double end fastener to be pull tested to determine a safe working load of the fastener and / or ensure adequate securement of the leading end and / or the first screw-thread to the surface.

[0016] In one embodiment, the fixture is a nut comprising an internal thread that is complementary to the second screw-thread.

[0017] In one embodiment, the fixture is an eye nut comprising a thread that is complementary to the second screw-thread.

[0018] In one embodiment, the fixture is a plate comprising a thread that is complementary to the second screw-thread.

[0019] In one embodiment, the plate is adapted to bear against the surface.

[0020] In one embodiment, in use, the plate is secured on the second screw-thread so as to engage and support the surface the double ended fastener is threaded onto.

[0021] In one embodiment, the fixture is a coupler comprising a thread that is complementary to the second screw-thread.

[0022] In one embodiment, the second screw-thread is a GEWI thread.

[0023] In one embodiment, in use, rotation applied to the drive socket in a first direction screws the first screw-thread into the surface, and rotation applied to the drive socket in an opposite direction removes the first screw-thread from the surface.

[0024] In one embodiment, in use, the first direction is a clockwise rotation that screws the first screw- thread into the surface, wherein in use, a counter-clockwise rotation applied to the first screw-thread removes the first screw-thread from the surface.

[0025] In one embodiment, the first screw-thread is a clockwise or right-hand screw thread, and the second screw-thread is a counter-clockwise or left-hand screw thread.

[0026] In one embodiment, the drive socket is sized and shaped for receiving a drive member of a power tool therein.

[0027] In one embodiment, the power tool can screw the double end fastener into the surface and is any one of a SDS drill, hammer drill, impact driver, impact wrench or the like.

[0028] In one embodiment, the power tool is run in reverse to remove the double end fastener from the surface.

[0029] In one embodiment, the shaft further comprises a central unthreaded portion spacing the leading and trailing ends apart.

[0030] In one embodiment, the central unthreaded portion is axially shorter than either of the leading and trailing ends.

[0031] In one embodiment, the double end fastener is a rock bolt and the surface is a rock body, wherein the rock bolt is adapted for installation into a borehole of the rock body.

[0032] In one embodiment, the borehole is pre-drilled in the surface by a drilling tool or a drilling machine prior to the installation of the double end fastener into the borehole.

[0033] In one embodiment, in use, the first screw-thread of the leading end is capable of self-drilling into the surface.

[0034] In one embodiment, the fastener is manufactured of a high yield steel material.

[0035] In one embodiment, the fastener is coated with a corrosion-resistant finish.

[0036] In one embodiment, the fastener is heat treated.

[0037] According to a second aspect of the present disclosure, there is provided a method for securing an object with respect to a surface using the double end fastener, the method comprising the steps of: predrilling a hole into the surface; applying an adhesive to at least one passageway along at least a portion of an elongated body of the double end fastener; using a power tool comprising a drive member to apply rotation to the double end fastener via the drive socket to screw the first screw-thread into the pre-drilled hole, wherein the adhesive flows into the hole via the at least one passageway to create a bond between the first screw-thread and the hole; and securing the object to a second screw-thread at a trailing end of the double end fastener and applying a pulling force to the fixture to test securement of the object to the surface.

[0038] For ease of description, a double end fastener embodying the present features is described below in its usual assembled position as shown in the accompanying drawings and terms such as leading, trailing, front, back, forward, rear, upper, horizontal, longitudinal etc., may be used with reference to this usual position. However, the double end fastener may be manufactured, sold, or used in orientations other than those described and shown here.BRIEF DESCRIPTION OF DRAWINGS

[0039] Embodiments of the present disclosure will be discussed with reference to the accompanying drawings wherein:

[0040] Figure 1 is an isometric view of a double end fastener according to a first embodiment;

[0041] Figure 2 is a side view of the double end fastener;

[0042] Figure 3 is an end view of the double end fastener;

[0043] Figure 4 is an alternate end view of the double end fastener;

[0044] Figure 5 is a sectional view along X-X in Figure 3;

[0045] Figure 6 is a schematic of detail B in Figure 5;

[0046] Figure 7 is a schematic of detail C in Figure 5;

[0047] Figure 8 is an isometric view of a double end fastener according to a second embodiment;

[0048] Figure 9 is a side view of the double end fastener of Figure 8;

[0049] Figure 10 is an end view of the double end fastener of Figures 8 and 9;

[0050] Figure 11 is an alternate end view of the double end fastener of Figures 8 to 10;

[0051] Figure 12 is a sectional view along Y-Y of Figure 10;

[0052] Figure 13 is a schematic of detail D in Figure 12;

[0053] Figure 14 is a schematic of detail E in Figure 11;

[0054] Figure 15 is an isometric view of a double end fastener according to a further alternative embodiment;

[0055] Figure 16 is a side view of the double end fastener in Figure 15;

[0056] Figure 17 is an end view of the double end fastener of Figures 15 and 16;

[0057] Figure 18 is an alternate end view of the double end fastener of Figures 15 to 17;

[0058] Figure 19 is a sectional view along Z-Z of Figure 19;

[0059] Figure 20 is a schematic of detail F in Figure 19; and

[0060] Figure 21 is a schematic of detail G in Figure 19.

[0061] In the following description, like reference characters designate like or corresponding parts throughout the figures.DESCRIPTION OF EMBODIMENTS

[0062] Referring now to Figures 1 through 6, there is illustrated a double end fastener 10 according to one form of this disclosure.

[0063] The double end fastener 10 comprises an elongated body 11, the elongated body 11 comprises a leading end 20 and a trailing end 30, wherein the leading 20 and trailing 30 ends are opposing ends of the body 11.

[0064] The leading end 20 of the body 11 comprises a first screw-thread 21, the first screw-thread 21 being adapted to screw into a surface (not illustrated). The first screw-thread 21 of the leading end 20 might be considered the end that is screwed, driven, or drilled into the surface into which the double end fastener 10 is to be secured to.

[0065] In one embodiment, the first screw-thread 21 of the leading end 20 is capable of self-drilling or self-tapping into the surface. In this embodiment, the double end fastener 10 might be considered a selfdrilling or self-tapping fastener. Additionally, in this embodiment, the first screw-thread 21 might be a threadform that is particularly selected for its ability to be driven into masonry or rock. In any one of the embodiments herein, it will be appreciated that the first screw-thread 21 is a threadform that is particularly selected based on its ability to be screwed, driven, or drilled into the surface into which the double end fastener 10 is to be secured to.

[0066] The trailing end 30 of the body comprises a second screw-thread 31 and a drive socket 32. The second screw-thread 31, in one embodiment, comprises a thread profile different to the first screw-thread 21, as illustrated in any one of the Figures. In these embodiments where the second screw-thread 31 differs from the first screw-thread 21, the second screw-thread 31 might be a GEWI Threadbar, such as, but not limited to, a GEWI 20mm left hand Threadbar of the type commonly utilised in mining andconstruction industries. It will be appreciated that alternate sizes and right hand versions of the GEWI Threadbar are envisaged for the second screw-thread 31. The inventor wishes to make note of the use of the GEWI 20mm left hand Threadbar, as an example, due to its robust threadform and coarse pitch threadform what comprises self-cleaning properties that make it an ideal candidate for use in mining and construction industries. It will also be appreciated that the second screw-thread 31 may be an alternate thread profile, such as any others that are utilised in the mining and construction industries being of high yield screwable stainless steel that is capable of being screwed to corresponding coupling and anchoring accessories. In an alternative embodiment, not illustrated, the second screw-thread 31 may comprise a thread profile the same as the first screw-thread 21.

[0067] In one embodiment, the first screw-thread 21 is a clockwise or right-hand screw thread, and the second screw-thread 31 is a counter-clockwise or left-hand screw-thread. This embodiment is illustrated within Figures 1 to 7. In an alternative embodiment, both first 21 and second 31 screw-threads are clockwise or right-hand screw threads. In another alternative embodiment, both first 21 and second 31 screw-threads are counter-clockwise or left-hand screw threads, this is illustrated in Figures 15 to 21. That is to say, the first 21 and second 31 screw-threads are not limited in their direction, and they may be alternatives such that the double end fastener 10 of this disclosure achieves its disclosed advantages.

[0068] The drive socket 32 at the trailing end 30 of the fastener 10 is sized and shaped for receiving a drive member of a power tool (not illustrated) therein. The power tool might be any one of a lightweight hand operated SDS rotary drill, hammer drill, impact driver, impact wrench, or the like. The power tool may also be a more heavy-duty hand operated SDS rotary hammer drill, or the like. In the embodiments herein, the drive socket 32, and thereby the double end fastener 10, is screwed, driven, or drilled into the surface for securement by a hand operated power tool that is commonly used, and readily available, in construction or mining industries, that does not require specialised training for its use. It will become apparent that this is an advantage of the double end fastener 10 disclosed herein, as other fasteners previously available required the use of heavy-duty machinery such as a hydraulic (or high voltage) jumbo drill (also referred to as hydraulic bolting jumbo), or a pneumatic underground rock drill - all of which require an operator to have specialised training, and all of which are often scarce on a mine or construction site due to their high cost.

[0069] The drive socket 32 at the trailing end 30 of the fastener 10 is screwed or driven in a first direction that screws the fastener 10 into the surface. This rotation in the first direction is provided by the power tool and delivered to the drive socket 32 by the drive member. The drive member may be any suitable bit that enables the power tool to connect to the drive socket 32. In one example, the drive socket 32 may be a hex socket (as illustrated in any one of Figures 3 or 9) and the drive member is a correspondingly shaped and sized hex bit (not illustrated, however well known to operators in mining and construction industries) that transmits drive from the power tool to the drive socket 32 to screw or drivethe fastener 10 in the first direction. It will be appreciated that the drive socket 32 is not limited to the hex socket illustrated in the Figures, and that it might be any alternate drive profile such as Philips, Pozidriv, Slotted, Square drive, Torx, or the like. The type of drive socket 32 will be selected based on the application of the fastener 10 and the advantages, grip and torque requirements required.

[0070] The drive socket 32 at the trailing end 30 of the fastener 10 might also have rotation applied from the power tool in an opposite direction to the first direction, which removes the first screw-thread 21 from the surface. In this way, screwing or driving the fastener 10 via the drive socket 32 in the first direction screws the fastener 10 into the surface, and screwing or driving the fastener 10 via the drive socket 32 in the opposite direction is considered reversing the fastener 10 back out of the surface. Accordingly, the fastener 10 might be removed from the surface and reused. It will be appreciated that, in the embodiments described thus far, the power tool is run in reverse (a function commonly found in many hand held power tools) to remove the double end fastener 10 from the surface.

[0071] Furthermore, in the illustrated embodiments, the drive socket 32 might be considered an internal drive socket 32 of the double end fastener 10. That is, referring to Figures 3, 5, 9 and 11, different embodiments of the fastener 10 illustrate the internal drive socket 32 as being within the peripheral end of the trailing end 30, such that the drive member is received within the drive socket 32, internal to the trailing end 30 of the fastener 10. In the illustrated embodiments, the internal drive socket 32 is illustrated as an internal hex socket, however it may be an alternate drive profile that is internal to the trailing end 30 of the fastener 10. It will be appreciated that the drive socket 32 is not envisaged as being limited to being an internal drive socket as illustrated, non-illustrated embodiments are envisaged, such as a drive socket that protrudes or extends from the trailing end 30 of the double end fastener 10. However, the inventor notes that there are advantages to the drive socket 32 being internal to the trailing end 30 of the fastener 10. These advantages might include, minimising the overall length of the fastener 10 by having an internal drive socket 32, reduced costs in production of the fastener 10 by reduction in material required for manufacture, and readily available hex bits or other drive members that are able to fit into an internal drive socket 32.

[0072] A further advantage of the internal drive socket 32 illustrated in the Figures is that, when compared to an external drive socket that extends from the trailing end, that all the second screw-thread 31 at the trailing end 30 is usable (or accessible) in a non-restrictive manner when a fixture is threaded or screwed onto the second screw-thread 31. In one example, wherein a fixture such as an eye nut (not illustrated) is threaded to the trailing end 30, due to the internal or recessed nature of the drive socket 32, a threaded portion of the eye nut that is able to be screwed or threaded onto the second screw-thread 31 without being obstructed or restricted by the internal drive socket 32. In this way, the threaded portion of the eye nut can be torqued right up until an eye portion of the eye nut abuts against the starting point of the second screw-thread 31 (i.e. also where the internal drive socket 32 is at the trailing end 30).

[0073] With reference to Figures 1 to 7, in one embodiment, the double end fastener 10 further comprises at least one passageway 40 that forms a helical or screw-like pattern along at least a portion of the elongated body 11. In this embodiment, the helical or screw-like form of the at least one passageway 40 extends from one end of the leading end 20 and terminates at a peripheral end 22 thereof. As best illustrated in Figure 1, the at least one passageway 40 might form the helical or screw-like pattern between, or in the spacing of, the threads of the first screw-thread 21.

[0074] With reference to Figures 8 to 14, in an alternative embodiment, the at least one passageway 40 creates a break in the first screw-thread 21 and extends in a direction parallel to the direction of elongation of the body 11. In this alternative embodiment, the at least one passageway might be described as a channel along the portion of the elongate body 11. It might also be considered that the passageway 40 of the alternate embodiment is a channel that extends through the first screw-thread 21 of the leading end 20 toward the periphery thereof. Also in this alternative embodiment, the fastener 10 might comprise three passageways 40 that are equi-spaced apart about the circumference of the fastener 10. With reference to Figure 13, which illustrates three passageways 40 that are equi-spaced apart, an example of the spacing between the passageways 40 is provided in the Figures, however it will be appreciated that alternate spacing for the passageways 40 is also envisaged. In non-illustrated embodiments, the fastener 10 may comprise any number of passageways 40, where each one or more passageways 40 permits flow of an adhesive along the portion of the elongated body 11.

[0075] In any one of the above embodiments illustrated in any one of Figures, the passageway 40 extends along at least a portion of the leading end 20 toward the peripheral end 22 thereof. The peripheral end 22 is the end at which the first screw-thread 21 of the leading end 20 terminates, and it is also the end that makes initial contact with the surface when the double end fastener 10 is in use.

[0076] Additionally in any one of the above embodiments, with reference to any one of the Figures, the at least one passageway 40 might alternatively be considered an internal groove, an internal pathway, a channelled passageway, or a conduit section of the double end fastener 10 that extends along at least a portion of the elongated body 11 in a direction from one end of the leading end 20 to a peripheral end 22 thereof.

[0077] Furthermore in any one of the above embodiments, with reference to any one of the Figures, the at least one passageway 40 is particularly advantageous in that it guides flow of an adhesive to the peripheral end 22 of the leading end 20 such that the adhesive is applied along the first screw thread 21 and the periphery 22 of the leading end 20 to effectively aid in securing the leading end of the fastener 10 to the surface. That is, the at least one passageway 40 is a channel for guiding the adhesive to best distribute it about the leading end 20 of the fastener 10 within the hole in the surface it is screwed or driven into to maximise contact and effectiveness of the adhesive to secure the fastener 10 to the surface.The adhesive might be a grout or other chemical additive that is particularly selected based on the application of the fastener 10 and the surface, that best aids in securing the leading end 20 of the fastener 10 to the surface. It will be appreciated that the adhesive is a grout or chemical additive that creates a bond between the leading end 20 and first screw-thread 21 of the fastener 10 and the surface.

[0078] Fasteners that are screwed or driven into surfaces in the construction and mining industries are often categorised by their Safe Working Load (or SWL) that is tested by “pull testing” the fastener once secured to the surface. The “pull test” may be conducted by a machine, such as an anchor pull tester or other tensile testing machine capable of attaching onto the exposed end of a fastener secured to the surface. The SWL is important in the construction and mining industries as it denotes the maximum weight or force that the fastener can safely handle and is often compared to ISO standards for legal and / or specific working requirements. The inventor notes that the unique size and geometry of the at least one passageway 40 distributes the adhesive in a uniform manner that creates a more effective bond between the leading end 20 and first screw-thread 21 of the fastener 10 and the surface, resulting in better securement of the fastener 10 within the surface that is subsequently able to achieve higher / improved SWLs compared to other fasteners that did not comprise the passageway.

[0079] Following the above disclosure, one exemplary embodiment of the double end fastener 10 comprises the elongated body 11, the body 11 comprising the leading end 20 comprising the first screw- thread 21 adapted to screw into the surface. The elongated body 11 also comprising the trailing end 30, which comprises the second screw-thread 31 and the drive socket 32. The elongated body 11 further comprises at least one passageway 40 that extends along at least a portion of the elongated body 11, such that, in use, rotation applied to the drive socket 32 enables the first screw-thread 31 to be screwed into the surface and the at least one passageway 40 permits flow of an adhesive into the surface, whereby the adhesive aids in securing the leading end 20 of the fastener 10 into the surface.

[0080] In one embodiment, not illustrated, the double end fastener 10 further comprises a fixture that is releasably attachable to the second screw-thread 31. In one example, the fixture, in use, enables the double end fastener to be “pull tested” to determine the SWL of the fastener 10 and / or ensure adequate securement of the leading end 20 to the surface. In one example, the fixture that enables the “pull test” to be conducted is a Pull Ring (not illustrated). The Pull Ring will typically comprise an internal thread that is complementary to the secondary screw-thread 32, in the example where the secondary screw-thread 32 is a GEWI Threadbar. The “pull test” is generally a mechanical test whereby the testing machine attaches onto the fixture that is attached onto the second screw-thread 31 and applies a pulling force in the direction of the trailing end 30. In the example of the Pull Ring, the mechanical testing machine attaches onto the Pull Ring that is screwed onto the second screw-thread 31, and a pulling force is applied to the Pull Ring to determine the SWL of the double end fastener 10.

[0081] In certain embodiments, the fixture might be, however is not limited to, any one of: a nut comprising an internal thread that is complementary to the second screw-thread 31; an eye nut comprising a thread that is complementary to the second screw-thread 31 ; a plate comprising a thread that is complementary to the second screw-thread 31 ; or a coupler comprising a thread that is complementary to the second screw-thread.

[0082] In the embodiments comprising the fixture, a portion of the fixture is adapted to bear against the surface. Such as, for example where the fixture is a plate, a surface of the plate is adapted to bear against the surface, such that the plate engages and supports the surface the double end fastener 10 is secured to.

[0083] In embodiments, the double end fastener 10 is utilised in the mining and construction industries to be secured into rock or masonry surfaces. In these embodiments, the fastener 10 is often installed into a borehole (not illustrated) pre-drilled into the rock or masonry surface by a drill or drilling machine such that securing the fastener 10 into these boreholes applies a confining force to the rock or masonry to thereby support these surfaces and supress the growth of microcracks. In the embodiments comprising the fixture, the fixture is screwed or threaded onto the second screw-thread 31 at the trailing end 30 of the fastener 10 exposed from the rock or masonry surface to apply the confining force. That is, the confining force is applied by tensioning up the fixture on the exposed trailing end 30 second screw-thread 31 of the fastener 10.

[0084] In embodiments where the double end fastener 10 is utilised in the mining and construction industries and the surface it is secured to is a rock or masonry surface, the double end fastener might be considered a rock bolt, an anchor bolt, a masonry anchor, or the like, wherein the bolt or anchor is adapted for installation into a borehole that is pre-drilled into the rock or masonry surface.

[0085] The double end fastener 10 might also comprise a central unthreaded portion 50, where the central unthreaded portion 50 spaces or separates the leading end 20 from the trailing end 30. The central untrusted portion 50 is illustrated in the Figures as being axially shorter than either the leading 20 and trailing 30 ends.

[0086] An exemplary method of use of the double end fastener according to the present disclosure might include the steps of:1. Using a power tool, with an appropriately sized drill bit, to pre-drill a hole into a surface, such as a rock face.2. In the exemplary case that the double end fastener of any one of Figures is utilised in this method, applying an adhesive, such as a grout or chemical additive, to at least one passageway along at least a portion of an elongated body of the double end fastener.3. Using a power tool, with an appropriately sized drive member, to apply rotation to the double end fastener via its drive socket, to screw a first screw-thread into the pre-drilled hole in the surface. The adhesive flows into the pre-drilled hole of the surface as the first screw-thread is screwed.4. Once screwed into the pre-drilled hole, the adhesive might require some time to adequately create a bond between the first screw-thread of the fastener and the pre-drilled hole of the surface.5. Securing an object or fixture, such as an eye nut, to a second screw-thread at a trailing end of the double end fastener and applying a pulling force to the fixture to test securement of the object to the surface. The pulling force may be a pre-calculated testing safe working load that ensures that the secured double end fastener is capable of handling certain loads whist secured to the surface.

[0087] Double end fasteners according to the present disclosure might be manufactured of a high yield steel material. The manufacture may be any known casting manufacturing means known for creating fasteners, screws, or bolts (such as by use of a reciprocating die in which the fastener may be rolled at extremely high pressures). It will be appreciated that the material of manufacture for the fastener can be any suitable material of the aforementioned processes. The choice of material is likely to be a steel mixed metal compound, however alternative materials for manufacture of the fastener are envisaged, and are not limited to those presently disclosed.

[0088] Additionally, the double end fastener of the present disclosure might be coated with a corrosionresistant finish that prevents the fastener from corroding and / or rusting. In this instance, the fastener may be manufactured of a steel mixed metal compound that prevents the steel from corroding or rusting.

[0089] Furthermore, the double end fastener of the present disclosure might be heat treated. In this case, the fastener might be heat treated to vary the hardness along the fastener, for example between the leading and trailing ends, to vary its ductility, reducing or increasing stress along different parts of the fastener. Alternatively, the fastener itself is not heat treated and it is the nut, eye nut, plate, coupler, or any otherfixture that is fixed to the trailing end second screw-thread of the fastener that is heat treated so that its hardness is greater / less than the fastener.

[0090] To recap, advantages of the present disclosure include:1. The double end fastener 10 is capable of being secured to a surface in the mining and construction industries using handheld power tools commonly and readily available (such as SDS drills, impact wrenches, impact drivers, and the like).2. The double end fastener 10 does not require operators to have specialised training, tickets, registration, or certification for installation / securement onto the surface, as a commonly and readily available handheld power tool can be utilised (instead of heavy- duty machinery such as a hydraulic / high voltage jumbo drill).3. The double end fastener 10 reduces potential hazards and requirement for risk assessment during use, as the fastener 10 does not require the use of heavy-duty machinery.4. The double end fastener 10 reduces the cost of installation when compared to other fasteners that require the use of heavy-duty machinery that are often scarce on construction or mining sites. Often, these heavy-duty machineries are pre-occupied with other jobs and this could lead to delays in installation of fasteners waiting for the machinery to become available for use. In contradistinction, the disclosed fastener 10 can be installed with readily available handheld power tools.5. The double end fastener according to the present disclosure might be manufactured by injection moulding, such as by moulding in two halves which are joined, or by casting. The material of manufacture could be any suitable for manufacture by the aforementioned processes. A most likely choice of material is a high strength steel composite.6. The double end fastener 10 is capable of use in applications where larger SWLs are not required. Such as those where the fastener 10 may be utilised in the mining and construction industries where a GEWI threadbar or the like are required for holding, attachment or fixture of smaller objects that do not require large SWLs. This advantage is particularly noticeable when considering that other fasteners in these industries generally require the use of large machinery for installation (i.e. Jumbo drills etc.), that achieve high SWLs that are often not required, leading to increased costs due to utilisingexpensive machinery for installation, and higher cost in using fasteners with higher SWLs for applications where lower SWLs are suitable.7. The drive socket 32 of the fastener 10 is an internal drive socket, which advantageously minimises the overall length of the fastener 10 by having an internal drive socket 32, which can lead to reduced costs in production of the fastener 10 by reduction in material required for manufacture, and ability to use readily available hex bits or other drive members that are able to fit into an internal drive socket.8. The at least one passageway 40 is particularly advantageous in that it guides flow of an adhesive to the periphery 22 of the leading end 20 such that the adhesive is applied along the first screw thread 21 and the periphery 22 of the leading end 20 to effectively aid in securing the leading end of the fastener 10 to the surface. This advantage is particularly noticeable when compared to existing fasteners that are typically only secured to a surface by either mechanical friction or chemical adhesion. The disclosed fastener 10 comprising the passageway is effectively able to employ both types of securement.9. The double end fastener 10 can apply a confining force to the rock or masonry surface being supported to supress the growth of microcracks in the rock or masonry. This confining force can be applied by tensioning up a fixture (such as a nut or eye nut) to the exposed second screw-thread 31 of the trailing end 30 of the fastener 10.

[0091] It will be appreciated that although the present disclosure is generally referred to as a ‘double end fastener’, it might alternatively be referred to as a rock bolt, a masonry bolt, an anchor, a screw, or the like comprising a body having screw threads on either end thereof.

[0092] The double end fastener disclosed herein can be utilised in countless applications, outside of those mentioned such as in mining and construction industries. The fastener can be used to create fast and effective, but readily reversable, securement to a surface that can be easily tested for its safe working load. Additionally, when referring to its particular use in the mining or construction industries, the double end fastener has its advantageous use in providing for a confining force that aids in supressing the growth of microcracks in rocks or masonry. Moreover, in any one of the applications that the double end fastener could be applied to, the securement of the fastener is improved using an adhesive product applied to the at least one passageway of the fastener by providing both a mechanical and chemical securement to the surface the fastener is intended to be secured to.

[0093] In the Figures, it will be appreciated that there are several embodiments of the double end fastener 10 illustrated for exemplary purposes. These different embodiments illustrate example threadpaterns on either the leading 20 or trailing 30 ends of the fastener, the example where the fastener comprises the at least one passageway 40, and various cross-sections or detail sections of these exemplary embodiments. A first embodiment of the fastener is illustrated in Figures 1 to 7, and a second embodiment of the fastener is illustrated in Figures 8 to 14. The inventor envisages other alternate embodiments of the fastener that are not illustrated in these included Figures.

[0094] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that such prior art forms part of the common general knowledge.

[0095] It will be understood that the terms “comprise” and “include” and any of their derivatives (e.g. comprises, comprising, includes, including) as used in this specification, and the claims that follow, is to be taken to be inclusive of features to which the term refers, and is not meant to exclude the presence of any additional features unless otherwise stated or implied.

[0096] In some cases, a single embodiment may, for succinctness and / or to assist in understanding the scope of the disclosure, combine multiple features. It is to be understood that in such a case, these multiple features may be provided separately (in separate embodiments), or in any other suitable combination. Alternatively, where separate features are described in separate embodiments, these separate features may be combined into a single embodiment unless otherwise stated or implied. This also applies to the claims which can be recombined in any combination. That is a claim may be amended to include a feature defined in any other claim. Further a phrase referring to “at least one of’ a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover: a, b, c, a-b, a-c, b-c, and a-b-c.

[0097] It will be appreciated by those skilled in the art that the disclosure is not restricted in its use to the particular application or applications described. Neither is the present disclosure restricted in its preferred embodiment with regard to the particular elements and / or features described or depicted herein. It will be appreciated that the disclosure is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope as set forth and defined by the following claims.

Claims

CLAIMS1. A double end fastener comprising: an elongated body comprising, a leading end comprising a first screw-thread adapted to screw into a surface, a trailing end comprising a second screw-thread and a drive socket, and at least one passageway extending along at least a portion of the elongated body; wherein, in use, rotation applied to the drive socket enables the first screw-thread to be screwed into the surface and the at least one passageway permits flow of an adhesive into the surface, whereby the adhesive aids in securing the leading end of the fastener to the surface.

2. The double end fastener of claim 1, wherein the at least one passageway extends along at least a portion of the leading end toward a periphery thereof.

3. The double end fastener of either claims 1 or 2, wherein the at least one passageway is a channel extending through the first screw-thread of the leading end toward a periphery thereof.

4. The double end fastener of claim 3, wherein in use, the channel guides flow of the adhesive to the periphery of the leading end such that the adhesive is applied along the first screw-thread and at the periphery of the leading end to effectively aid in securing the leading end of the fastener to the surface.

5. The double end fastener of any one of the preceding claims, wherein the adhesive is a grout or chemical additive that aids in securing the leading end of the fastener to the surface, wherein in use, the grout or chemical additive creates a bond between the leading end of the fastener and the surface.

6. The double end fastener of any one of the preceding claims, wherein the double end fastener further comprises a fixture that is releasably attachable to the second screw-thread.

7. The double end fastener of claim 6, wherein in use, the fixture enables the double end fastener to be pull tested to determine a safe working load of the fastener and / or ensure adequate securement of the leading end and / or the first screw-thread to the surface.

8. The double end fastener of either claim 6 or 7, wherein the fixture is any one of; a nut, an eye nut, a plate, or a coupler.

9. The double end fastener of any one of the preceding claims, wherein the second screw-thread is a GEWI thread.

10. The double end fastener of any one of the preceding claims, wherein in use, rotation applied to the drive socket in a first direction screws the first screw-thread into the surface, and rotation applied to the drive socket in an opposite direction removes the first screw-thread from the surface.

11. The double end fastener of claim 10, wherein in use, the first direction is a clockwise rotation that screws the first screw-thread into the surface, wherein in use, a counter-clockwise rotation applied to the first screw-thread removes the first screw-thread from the surface.

12. The double end fastener of any one of the preceding claims, wherein the drive socket is sized and shaped for receiving a drive member of a power tool therein.

13. The double end fastener of claim 12, wherein the power tool can screw the double end fastener into the surface and is any one of a SDS drill, hammer drill, impact driver, impact wrench or the like.

14. The double end fastener of either claims 12 or 13, wherein the power tool is run in reverse to remove the double end fastener from the surface.

15. The double end fastener of any one of the preceding claims, wherein the shaft further comprises a central unthreaded portion spacing the leading and trailing ends apart.

16. The double end fastener of claim 15, wherein the central unthreaded portion is axially shorter than either of the leading and trailing ends.

17. The double end fastener of any one of the preceding claims, wherein the double end fastener is a rock bolt and the surface is a rock body, wherein the rock bolt is adapted for installation into a borehole of the rock body.

18. The double end fastener of claim 17, wherein the borehole is pre-drilled in the surface by a drilling tool or a drilling machine prior to the installation of the double end fastener into the borehole.

19. The double end fastener of any one of the preceding claims, wherein in use, the first screw-thread of the leading end is capable of self-drilling into the surface.

20. A method for securing an object with respect to a surface using the double end fastener of claim 1, the method comprising the steps of: pre-drilling a hole into the surface; applying an adhesive to at least one passageway along at least a portion of an elongated body of the double end fastener;using a power tool comprising a drive member to apply rotation to the double end fastener via the drive socket to screw the first screw-thread into the pre-drilled hole, wherein the adhesive flows into the hole via the at least one passageway to create a bond between the first screw-thread and the hole; and securing the object to a second screw-thread at a trailing end of the double end fastener and applying a pulling force to the fixture to test securement of the object to the surface.

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