AU2012275031B2

AU2012275031B2 - Improvements to linking members

Info

Publication number: AU2012275031B2
Application number: AU2012275031A
Authority: AU
Inventors: Glen Ogden
Original assignee: David Scott Holdings Pty Ltd
Current assignee: David Scott Holdings Pty Ltd
Priority date: 2012-12-24
Filing date: 2012-12-24
Publication date: 2016-01-21
Anticipated expiration: 2032-12-24
Also published as: AU2016200801A1; AU2012275031A1

Abstract

This invention relates to an improved link 60 that comprises a linking member 10 having two opposing curved end portions 11 to which there are attached wear crutches 40. k co - N U~) tvj Lii

Description

IMPROVEMENTS TO LINKING MEMBERS Field of the Invention The present invention relates to improvements to linking members, including wear crutches for linking members. Background Art It has been observed that curved end portions of linking members, such as chain links and shackles, are more susceptible to wear through use than other portions. For example, linking members, including shackles and individual chain links, operatively connected to a dragline bucket have multiple wear points that as a consequence of use experience considerable wear necessitating their periodic checking and/or replacement. In an effort to increase the life of a chain, individual links have previously been provided with one or more sacrificial wear elements that are adapted to cover at least a portion of an inner surface of the curved end portion. For example, individual pieces of metal have previously been welded to the inner surface of a curved end portion of a link so as to increase the thickness thereof and whereby selected portions of the metal elements were subsequently ground away so as to produce a substantially curved inner working surface. This process of building a wear crutch is very labour intensive and accordingly quite expensive to produce. In other embodiments, the wear element has resembled a cover that is adapted to fit over an end portion of a linking member which itself may include a seat portion that is -2 specifically adapted to receive and/or engage with said cover. However, because linking members typically include opposing side portions having inner surfaces that are substantially parallel, in order to locate the aforementioned cover on the curved end portion, the cover typically comprised multiple components and whereby the cover was assembled on the linking member. Wear elements of this type have also proved to be time consuming to build and/or replace. Accordingly, a wear element that comprises a single casting would be preferable. It has also been observed that many wear elements have been designed for use in conjunction with linking members having a substantially rectangular shaped transverse cross section and are therefore not suitable for use in conjunction with linking members having a substantially oval shaped transverse cross-section including a substantially curved inner surface. (The word "oval" is taken to include a geometric figure that closely resembles two opposed semi circles that are joined by a rectangle. The resulting figure has to straight sides and two semi-circular ends.) Summary of the Invention It is therefore an object of the present invention to provide an improved linking member and an improved wear crutch for a linking member which alleviates at least some of the deficiencies of the prior art and which will be reliable and efficient in use. In one aspect, this invention relates to a wear crutch for a linking member having a substantially oval or elliptically shaped transverse cross-section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side portions, and whereby said curved end portion - 3 includes a substantially flat seat that is adapted to provide support for said wear crutch, said wear crutch including: a wear body having an outer wear surface that is substantially curved in both the longitudinal and transverse 5 directions and an opposing inner surface that includes a substantially flat load bearing face which is adapted to rest upon the substantially flat seat, and locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent LO movement of said wear body relative to said seat in both longitudinal and transverse directions, and whereby in use said outer wear surface is substantially flush with the adjacent inner face of the linking member. In another aspect, this invention relates to a wear crutch L5 for a linking member having a substantially oval or elliptically shaped transverse cross-section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side. portions, said wear ?o crutch including: a wear body having an inner surface and an opposing outer wear surface that is substantially curved in both the longitudinal and transverse directions, said curvature in the transverse direction closely resembling the curvature of inner 25 face of the linking member; locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent movement of said wear body relative to said linking member in both longitudinal and transverse directions, and whereby in use 30 said outer wear surface is substantially flush with the adjacent inner face of the linking member; and - 4 a substantially flat face between opposing ends of said wear body and whereby this flat face is adapted to abut a substantially flat face on the curved end portion. In still yet another aspect, this invention relates to a 5 wear crutch for a linking member having a substantially oval or elliptically shaped transverse cross-section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side .o portions, and whereby said curved end portion includes a seat that is curved in both the longitudinal and transverse directions, said seat being adapted to provide support for said wear crutch, said wear crutch including: a wear body having an outer wear surface that is .5 substantially curved in both the longitudinal and transverse directions and an opposing inner surface that includes a load bearing face which is adapted to rest upon the seat, said load bearing face being curved in both the longitudinal and transverse directions, and !0 locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent movement of said wear body relative to said seat in both longitudinal and transverse directions, and whereby in use said outer wear surface is substantially flush with the adjacent 25 inner face of the linking member, wherein said load bearing surface includes a substantially flat face approximately midway between opposing ends of the wear body and whereby this flat face is adapted to abut a substantially flat face on the curved end portion. 30 In still yet another aspect, this invention relates to a linking member that is adapted to cooperate in use with a wear crutch, said linking member including: - 5 two opposing side portions each having a substantially oval or elliptically shaped transverse cross-section, including a first curved inner face and a first curved outer face; an end portion connecting said side portions, said end 5 portion having a second curved outer surface of similar curvature to that of said first curved outer face and a substantially flat seat that is adapted to provide support for the wear crutch, locating means associated with said substantially flat seat which is adapted to engage with the wear crutch so to prevent LO movement of the wear crutch in both the longitudinal and transverse directions relative to said linking member, wherein the wear crutch further includes a substantially flat face which is adapted to engage the substantially flat seat of the linking member. LS Preferably the first curved inner faces of the two side portions diverge away from the end portion. In still yet another aspect, this invention relates to a link including: a linking member having two opposing side portions each o having a substantially oval or elliptically shaped transverse cross-section, including a first curved inner face and a first curved outer face; an end portion connecting said side portions, said end portion having a second curved outer surface of similar 25 curvature to that of said first curved outer face and a substantially flat seat; a wear crutch having a load bearing outer wear surface that is substantially curved in both the longitudinal and transverse directions, said curvature in the transverse direction generally 30 resembling the curvature in the transverse direction of said first inner curved surface, and an opposing inner surface that - 6 includes a substantially flat load bearing face which is adapted to rest upon the substantially flat seat, and locating means associated with both said linking member and said wear crutch for preventing movement of said wear crutch 5 relative to said linking member in both the longitudinal and transverse directions. Preferably the locating means includes one or more keys that are each adapted to engage a substantially complementary shaped keyway. .0 Alternatively the locating means may include one or more keyways that are each adapted to receive a substantially complimentary shaped key. Brief Description of the Drawings Various embodiments of the invention will be described with .5 reference to the following drawings, in which: Figure 1 is a front view of a linking member constructed in accordance with the present invention; Figure 2 is a side cross-sectional view of the linking member shown in figure 1; -0 Figure 3 is a pictorial view of the linking member shown in figure 1; Figure 4 is a side view of a wear crutch constructed in accordance with the present invention; Figure 5 is a bottom view of the wear crutch shown in figure 4; 25 Figure 6 is a side view of the wear crutch shown in figure 4; Figure 7 is a cross-sectional side view of the wear crutch shown in figure 4; Figure 8 is a pictorial view of the wear crutch shown in figure 8; 30 Figure 9 is a front view of a link constructed in accordance with the present invention; -7 Figure 10 is a cross-sectional side view of the link shown in figure 9, and Figure 11 is pictorial view of the link shown in figure 9. Detailed Description of the Preferred Embodiments Figures 1 to 3 show an open, continuous, linking member 10 which, when viewed front on, is substantially elliptical or oval in shape. The linking member 10 has a substantially continuous, oval or elliptically shaped, transverse cross-section. The linking member 10 includes two opposing curved end portions 11 that each connect to two opposing, diverging, side portions 12 such that the enclosed opening 13 of the linking member is widest midway between said opposed curved end portions 11. Each side portion 12 includes a substantially curved inner face 14 and an opposing, substantially curved outer face 15. The two curved end portions 11 each include a seat 16 and an opposing, substantially curved, outer face 17. The seat 16 includes a mid-portion having a substantially flat face 18 located between opposed end portions 19 that are each substantially curved in both the longitudinal and transverse directions. Each end portion 11 also includes locating means 20 for assisting with the location thereon of a wear crutch 40, including two opposed, substantially crescent shaped, side recesses 21 each formed in an opposing side portion 22 of the end portion 11 and located on either side of the seat 16. Further, the side recesses 21 each extend substantially the length of the seat portion 16.

-8 The locating means 20 also includes a generally rectangularly shaped keyway 23, having a "necked" mid-portion 24, the keyway 23 being formed in the seat portion 16 midway between its curved ends 25, said keyway 23 extending transversely across the flat face 18. The locating means 20 also includes two opposing, substantially rectangularly shaped, keyways 26 each formed in an opposing curved end face 19 of a curved end portion 25, said keyways each having a longitudinal axis of symmetry that is contained within a plane bisecting the linking member and the keyway 23 midway between its ends, namely where its recess is narrowest. The keyways 26 each become deeper away from the end that is closest to the outer periphery of the curved end portions 25. Each end portion 11 also includes opposed, shallow, substantially rectangularly shaped, open ended, maintenance channels 27, each formed in an opposing side wall 28. Further,.each maintenance channel 27 communicates with an adjacent, crescent shaped side recess 21. Figures 4 to 8 show a wear crutch 40 that includes a wear body 41 located between opposed, substantially crescent shaped, flanges 42, each having a curved free end portion 43. The wear body 41 has an outer wear surface 44 and an opposing inner, seat engaging surface 45. The wear surface 44 is substantially curved in both the longitudinal and transverse directions. The inner surface 45 includes a substantially flat, generally rectangularly shaped, mid-portion 46 flanked on either side by end portions 47 that are each substantially -9 curved in both the longitudinal and transverse directions, and which compliment the curved shape of the curved end faces 19. The end portions 47 each intersect adjacent end portions of the wear surface 44 along respective common curved edges 48. The wear crutch 40 includes locating means 50 for locating the wear crutch on the linking member 10, including two crescent shaped protrusions 51 that depend from the inner surface 45 and extend inwardly from the flanges 42. The crescent shaped protrusions 51 are each locatable within a respective, complementary shaped, side recess 21. The locating means 50 also includes a substantially rectangularly shaped key 52 that depends from the mid-portion 46 and which extends transversely across the mid-portion intermediate its opposing ends. The key 52 has a necked mid portion and is locatable within the complementary shaped keyway 23. The locating means 50 further includes two keys 53 that depend from respective end portions 47. The keys 53 each generally resemble a rectangularly shaped prism and are each locatable within a respective complementary shaped keyway 26. Figures 9 to 11 show a link 60 comprising a linking member 10 to which there is attached two wear crutches 40. In use, the wear crutches 40 are each slideably located on a respective curved end portion 11 such that the two crescent shaped protrusions 51 are received by respective recesses 21; the key 52 is received by the keyway 23, and the keys 53 are received by the respective keyways 26, until the inner surface 45 abuts against the mid portion 18 and the curved end faces 19.

- 10 In order to remove a worn wear crutch 40, firstly any pins retaining it in its operative position must be removed and any welds gouged away. Then a tool that is adapted to slide within the maintenance channel 27 may be employed to push against an adjacent edge portion of a flange 42 so as to separate the wear crutch from the linking member. In some embodiments there may be provided two opposing tools that simultaneously are adapted to engage opposing flanges 42 of the wear crutch 40. It is believed that because the outer surface 44 of the wear crutch 40 lies flush with adjacent surfaces of the linking member 10, links 60 equipped with the wear crutches 40 will slide relative to one another during use and are unlikely to snag one another or jam as a consequence of edge portions that stand proud. It will of course be realised that while the foregoing description has been given by way of example of this invention, all other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as herein defined by the appended claims.

Claims

1. A wear crutch for a linking member having a substantially oval or elliptically shaped transverse cross section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side portions, and whereby said curved end portion includes a substantially flat seat that is adapted to provide support for said wear crutch, said wear crutch including: a wear body having an outer wear surface that is substantially curved in both the longitudinal and transverse directions and an opposing inner surface that includes a substantially flat load bearing face which is adapted to rest upon the seat, and locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent movement of said wear body relative to said seat in both longitudinal and transverse directions, and whereby in use said outer wear surface is substantially flush with the adjacent inner face of the linking member.

2. A wear crutch for a linking member having a substantially oval or elliptically shaped transverse cross section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side portions, said wear crutch including: a wear body having an inner surface and an opposing outer wear surface that is substantially curved in both the longitudinal and transverse directions, said curvature in the 12 transverse direction closely resembling the curvature of inner face of the linking member; and locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent movement of said wear body relative to said linking member in both longitudinal and transverse directions, and whereby in use said outer wear surface is substantially flush with the adjacent inner face of the linking member.

3. A wear crutch for a linking member having a substantially oval or elliptically shaped transverse cross section, said linking member including a substantially curved inner face and a substantially curved outer face, said linking member also having at least one curved end portion that connects two opposing side portions, and whereby said curved end portion includes a seat that is curved in both the longitudinal and transverse directions, said seat being adapted to provide support for said wear crutch, said wear crutch including: a wear body having an outer wear surface that is substantially curved in both the longitudinal and transverse directions and an opposing inner surface that includes a load bearing face which is adapted to rest upon the seat, said load bearing face being curved in both the longitudinal and transverse directions, and locating means, that extends away from said inner surface, which is adapted to engage the linking member so as to prevent movement of said wear body relative to said seat in both longitudinal and transverse directions, and whereby in use said outer wear surface is substantially flush with the adjacent inner face of the linking member. 13

4. A wear crutch as claimed in claim 3, wherein said load bearing surface includes a substantially flat face approximately midway between opposing ends of said wear body and whereby this flat face is adapted to abut a flat face on the curved end portion.

5. A wear crutch as claimed in any one of claims 1 to 4, wherein said locating means includes a substantially rectangularly shaped key located approximately midway and transversely between opposing ends of said wear body.

6. A wear crutch as claimed in claim 5, wherein said substantially rectangularly shaped key has a necked mid portion.

7. A wear crutch as claimed in claim 5 or claim 6 wherein said locating means further includes two keys that each extend from a position towards each opposing end of said wear body.

8. A linking member when used to cooperate with a wear crutch as claimed in any one of claims 1 to 7 , said linking member including: two opposing side portions each having a substantially oval or elliptically shaped transverse cross-section, including a first curved inner face and a first curved outer face; an end portion connecting said side portions, said end portion having a second curved outer surface of similar curvature to that of said first curved outer face and a seat that is adapted to provide support for the wear crutch, and locating means associated with said seat which is adapted to engage with the wear crutch so to prevent movement of the 14 wear crutch in both the longitudinal and transverse directions relative to said linking member.

9. A linking member as claimed in claim 8, wherein said first curved inner faces of the two side portions diverge away from the end portion.

10. A linking member as claimed in claim 8 or claim 9 when used to cooperate with two wear crutches, wherein the linking member has a second end portion also connecting said side portions, said second end portion also having a second curved outer surface of similar curvature to that of said first curved outer face and a seat that is adapted to provide support for a cooperated wear crutch, and locating means associated with said seat which is adapted to engage with the cooperated wear crutch so to prevent movement of the wear crutch in both the longitudinal and transverse directions relative to said linking member.

11. A linking member as claimed in claim 10 which further includes a maintenance channel at each end portion for receiving a tool that is adapted so slide therein.

12. A link including: a linking member having two opposing side portions each having a substantially oval or elliptically shaped transverse cross-section, including a first curved inner face and a first curved outer face; an end portion connecting said side portions, said end portion having a second curved outer surface of similar curvature to that of said first curved outer surface and a 15 seat; a wear crutch having a load bearing outer wear surface that is substantially curved in both the longitudinal and transverse directions, said curvature in the transverse direction generally resembling the curvature in the transverse direction of said first inner curved surface, and an opposing inner surface that includes a load bearing face which is adapted to rest upon the seat, and locating means associated with both said linking member and said wear crutch for preventing movement of said wear crutch relative to said linking member in both the longitudinal and transverse directions.

13. A link as claimed in claim 12 wherein the linking member has a second end portion also connecting said side portions, said second end portion also having a second curved outer surface of similar curvature to that of said first curved outer face and a seat, a second wear crutch and locating means associated with said second seat which is adapted to engage with the second wear crutch so to prevent movement of the second wear crutch in both the longitudinal and transverse directions relative to said linking member.

14. A link as claimed in claim 12, wherein said locating means includes one or more keys that are each adapted to engage a substantially complementary shaped keyway.

15. A link as claimed in claim 14, wherein said locating means of each said wear crutch includes a substantially rectangularly shaped key located approximately midway and transversely between opposing ends of said wear body. 16

16. A link as claimed in claim 15 wherein said locating means further includes two keys that each extend from a position towards each opposing end of each said wear body.

17. A link as claimed in claim 13, wherein said locating means includes one or more keyways that are each adapted to receive a substantially complimentary shaped key.

18. A link substantially as hereinbefore described with reference to the accompanying drawings.

19. A wear crutch substantially as hereinbefore described with reference to the accompanying drawings.

20. A linking member when used to cooperate with a wear crutch as claimed in claim 19, substantially as hereinbefore described with reference to the accompanying drawings.