AU2013204673A1 - Chain connector - Google Patents

Abstract

A vertical or block chain connector (10) for linking between two closed chain links comprising a lower element (14) and an upper element (16) configured to engage with the lower element to form the chain connector. In in use the lower element is disposed vertically below the upper element in the assembled connector. The top of the upper element is wider (preferably at least about 10-20% wider) than the width of the bottom element so that the surface area of the top of the connector is greater than the surface area of the bottom of the connector. A series of bores (80, 82 84) extend through the upper and lower elements for receiving pins connecting the elements together. In a preferred aspect, at least two of the bores are oriented in a non-parallel axis to one another. Typically, with respect to a notional horizontal plane passing through the centre of the assembled connector, the bores will extend at an angle to that plane, typically from 30 to 600 to that plane. Having the pins extending in different directions rather than the same direction, and in particular is a non-horizontal plane means that the chances of all the pins working free due to vibrations or the like are much reduced. . '.LJtu. So IG g Draft tp - V SECTIfJI A-A SECTION 3-3 WEND C-C ViA 10t

Description

AUSTRALIA Patents Act 1990 ACT (EUROPE) LTD COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Chain connector The following statement is a full description of this invention including the best method of performing it known to us:- 2 Cross-Reference to Related Applications The present application claims priority from Australian Provisional Patent Application No 2012903913 filed on 7 September 2012, the content of which is incorporated herein by reference. 5 Field of the Invention This invention relates to a connector for a chain, and particularly to a block connector for a mining chain. 10 Background of the Invention Mining chains are used in underground mining, particularly in longwall coal mining. Conditions in mines are tough and mining chains are subject to heavy wear and tear. Most commonly, mining chains are used to pull flight bars which in turn drag mined coal away from the coalface in troughs/channels sometimes referred to as a 15 "chain conveyor". Lengths of chain are connected to one another to make a closed loop of the required length using connectors, either flat connectors or block connectors. 'Vertical' or 'vertical block type' connectors are used in a vertical orientation, with flat connectors typically used in a horizontal orientation. 20 Ideally, the connectors need to be as strong as the other links of the chain but at the same time, they need to be separable to link/unlink the lengths of chain. They are expensive to manufacture as they typically require forging and machining and are prone to wear and fracture due to their complicated design and the rough treatment that the chains receive. One other common problem is that the pins which are used to hold 25 the two parts of the connector together often work loose as the chain is dragged around its trough. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general 30 knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application. Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of 35 any other element, integer or step, or group of elements, integers or steps.

3 Summary of the Invention In a first aspect of the present invention there is provided vertical or block chain connector for linking between two closed chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain 5 connector, in use the lower element being disposed vertically below the upper element in the assembled connector wherein the top of the upper element is wider than the width of the bottom element. In a preferred aspect, the top of the upper element is wider at least about 10% preferably 20% wider than the width of the bottom element so that the surface area of 10 the top of the connector is greater than the surface area of the bottom of the connector. In a preferred aspect a series of bores extend through the upper and lower elements for receiving pins connecting the same and at least two of the bores are oriented in a non-parallel axis to one another. Typically, with respect to a notional horizontal plane passing through the centre 15 of the assembled connector, the bores will extend at an angle to that plane, typically from 30 to 60" to that plane. Having the pins extending in different directions rather than the same direction, and in particular is a non-horizontal plane means that the chances of all the pins working free due to vibrations or the like are much reduced. 20 In a second broad aspect of the present invention there is provided a connector , typically a vertical or block chain connector for linking between two closed chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, wherein in use the lower element is disposed vertically below the upper element in the assembled connector wherein a series of bores 25 extend through the upper and lower elements for receiving pins connecting the same and wherein at least two of the bores are oriented in a non-parallel axis to one another. In a third broad aspect there is provided a vertical block chain connector for linking between two chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, wherein, in 30 use, the lower element is disposed vertically below the upper element in the assembled connector, wherein in which the functionality of the connector is provided such that the connector can still function in a chain conveyor after failure of the upper element. Brief Description of the Drawings 35 A specific embodiment of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which:- 4 Figure 1 is an isometric view of an assembly of a first embodiment of vertical chain connector connected to two horizontal chain links; Figure 2 is a side view of the assembly shown in Figure 1; Figure 3 is a top plan view of the assembly shown in Figure 1; 5 Figure 4 is a vertical cross-section on X-X shown in Figure 3; Figure 5 is an end view of the assembly shown in Figure 1; Figure 6 is a section on A-A shown in Figure 2; Figure 7 is a section on B-B shown in Figure 2; Figure 8 is a section on C-C shown in Figure 2; 10 Figure 9 is a side view of a lower element of the chain connector of Figure 1; Figure 10 is an isometric view of the upper side of the lower element shown in Figure 9; Figure 11 is a side view of an upper element of the chain connector of Figure 1; Figure 12 is an isometric view of the underneath of the upper element shown in 15 Figure 11; Figure 13 is an isometric view of a second embodiment of a chain connector embodying the invention. Figure 14 is an end view of the assembly shown in Figure 1; Figures 15 to 17 are sectional views; and 20 Figure 18 is an isometric view of the upper side of the lower element of the assembly shown in Figure 13. Detailed Description of Preferred Embodiments Referring to the drawings, Figure 1 shows an assembly of a chain connector 25 block 10 according to a first embodiment of the invention, connected to two chain links 12 in the form of rounded/oval steel chains. The chain connector includes a generally w-shaped stirrup or lower element 14 and an upper element 16 which mates with the lower portion to close the connector to provide two closed rings which retain the chain links 12. The chain connector is of the block/vertical type, that is to say in operation 30 the chain connector is used upright as shown in Figure 1, in a vertical plane, with the chain links 12 being in a horizontal plane. The chain is typically used to drag flight bars in a chain conveyor (not shown) and in use the upper element is disposed above the lower element 14, when dragging mined coal, ore or the like, and on its return journey the vertical positions of the two elements are reversed. The lower part of the 35 connector 14 passes through the sprockets of the conveyor.

5 Figures 9 and 10 show the lower element 14 in more detail. It is symmetrical about a central vertically extending plane/axis V passing through the central axis A of the lower element 14 and defines a longitudinally extending portion 20 defining a claw like arcuate segment 22, 24 at each end. A stud 26 projects up along the axis A and 5 defines a contoured male coupling element 28 at its upper end in the form of six bulbous projections 30 separated by valleys 32. The stud divides the lower element 14 into two U-shaped receptacles 34 for receiving horizontal chain links. It is to be noted that the side walls of the U-shaped receptacles 34 are planar and the upper portion extends perpendicularly from the base of the lower element, vertically 10 in line with the opening at the top of the link along the line V-V shown in Figure 9. This makes it easier to insert a horizontal link and avoids loss of tension when the horizontal link is dropped into the connector as happens with existing designs. In this way, in contrast with existing connector designs, the chain does not have to be tensioned higher to generate more slack to allow the horizontal link to drop into the 15 connector, after which time the link settles back into the contacting arcs of the connector and loses some tension. The outer faces, in particular the lower side/bottom 36 and end faces 38 of the lower element are smooth and generally planar with rounded radiused edges where the front and rear faces of the connector meet. 20 The arcuate segments 22, 24 at each end of the lower element 14 define a rounded end wall portion 38, a recessed portion 40 and an inner end wall 42 facing and spaced from the stud whose top is lower than that of the end wall 38. The recess 40 defines a rounded convex surface/saddle. As is best seen in Figure 10, a vertically extending slot or key way 44 is defined in the inner wall 42 facing the stud 26. 25 Figures 11 and 12 show the upper element 16 which attaches to the lower element to complete the chain connector and retain the chain links in more detail. It is symmetrical about a central vertically extending plane/axis V passing through the central axis A of the lower element 16 The upper element 16 includes a longitudinally extending portion 50. A 30 depending end formation 52 is defined at each end of the portion 50. Each end formation comprises two transversely opposed walls 54 separated by a recess 56. The interior shape of the recess 56 corresponds to the exterior shape of the saddle portion 40 of the lower element 14. In the centre of the upper element there is a contoured recess 59 whose interior corresponds to the exterior of male coupling/engagement means 35 defined on the top of the stud. Between the end formations 52 and the recess 54 there is a depending element which defines a generally planer face 58 opposing the end wall 6 and an arcuate wall 56 facing the recess 54. The planar face 58 defines an elongate, vertically extending projection or rib 60 having a generally trapezoidal cross-section, best seen in Figure 12. As is best seen in Figures 1 to 8, the upper element is shaped and configured to 5 be a close fit to the lower element with minimal clearance to prevent relative movement of the two components during use. In particular, the male coupling element 28 locates in the recess 59 of the upper element. The end formations 52 fit snugly between the end wall 38 and inner end wall 42 of the lower element, with the recess 56 abutting the surface of the saddle portion 40 of the lower element 14. The projections 60 locate in 10 respective keyways 44 of the lower element. The resultant chain connector block is extremely strong with particular strength and maximised mechanical properties in the lower section 14. With reference to Figure 4 in particular, the width W is maximised when the upper element is remove to minimise the amount of slack required in the chain when 15 locating two end links of the chain in the lower connector. Figures 1 to 8, and in particular Figures 6 to 8 show how the upper element is secured to the lower element using angled locking pins (these are typically split roll pins) passing through bores 80, 82, 84 in the upper and lower elements which align when the elements are connected. The bores all extend at an angle to the horizontal 20 plane Y-Y. Also, with reference to Figures 6 to 8, the bores 80 - 84 extend at an angle to a notional plane P passing along the length of the connector through axis P 1 , P 2 and

P

3 . There are three bores which extend through the upper element and into the lower element, two outer bores 80 and 84 which extend through the centre of the 52 and one through the centre of the upper element into the stud 26. The angles a,, a 2 , and a 3 may 25 vary. As shown angles a,, a 2 are about 30" to the vertical while a 3 is about 450 to the vertical axis P. Typically the angles will be from 30 to 600. It is important to note that the bores are not all parallel to each other (or to the horizontal axis) while the two bores 80 and 84 are substantially parallel, the central bore 82 is not parallel to the outer bores and extends at an angle of about 800 to the outer bores. 30 The pins, being located with their heads near the upper face of the chain connector, are easy to access for removal. Because the pins pass through the connector at an angle to the horizontal, in particular at at least two differing angles, the pins may be less likely to work loose than in prior connectors where the pins are all aligned in the same horizontal plane. 35 Figures 5 to 8 in particular illustrate that the width we of the upper section of the chain connector is greater that the width wt of the lower section of the chain connector.

7 this provides a greater surface area for the top of the connector than its bottom. The main advantage of this feature is that the increased volume of steel provides a better mechanical interface between the two components providing a more reliable connection between the two and a greater contacting surface area. The greater width 5 w, also helps to decrease the wear rate of the connector. When the upper element is removed, as shown in Figures 9 and 10, the areas 34 into which the chain links are held is fully open at the top thus minimising the amount of chain slack required to use the connector 10 to connect two chain links. Advantageously, the greater surface area of the upper section spreads the load 10 applied by the connector to the pan in which the chain runs and helps to reduce pan line wear. The asymmetry of the connector helps maximise the mass of the connector, and means that the connector can only be installed in one orientation, with the narrower section running through the sprockets of the chain drive. Advantageously, in the above design, the strength of the connector is largely in 15 the lower element so even where the upper element fails, the lower section will retain the required mechanical properties even after that failure, which reduces the risk of damage to the machinery in the event of failure of the upper element. Figures 13 to 18 show a variant of the connector block 100 which is substantially the same functionally as the first embodiment but is shaped to suit a 20 different chain type. In particular as can be seen from Figures 15 to 17, the bores 80, 82 and 84 for locking pins all extend at an angle to the horizontal plane Y-Y. In the embodiment shown in Figures 15 to 17 the angles a], a 2 and U3 are all about 45" to the vertical axis P-P. The key difference lies in the shape of the stud 126 which projects up along the 25 axis A and defines a contoured male coupling element 128 at its upper end in the form of a simple rectangular lozenge, rather than the bulbous portions separated by valleys of the first embodiment. The female coupling element (not shown) is configured to receive the male coupling element 128. It will be appreciated by persons skilled in the art that numerous variations 30 and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (14)

1. A connector for linking between two closed chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, in use the lower element being disposed vertically below the upper 5 element in the assembled connector wherein the top of the upper element is at least 10% wider than the width of the bottom element.

2. A connector as claimed in claim I wherein the top of the upper element is wider at least about 10%, preferably 20% wider, than the width of the bottom element so that 10 the surface area of the top of the connector is greater than the surface area of the bottom of the connector.

3. A connector as claimed in claim 1 or claim 2 wherein the lower element is generally symmetrical about a central axis and defines arcuate segments at each end 15 and a stud which projects up from the central axis, dividing the lower element into two generally U-shaped portions for receiving links, and which defines a first, typically male, coupling element at an upper end.

4. A connector as claimed in claim 3 wherein the side walls of the lower element 20 are planar and have an upper portion which is planar and extends in a plane which is generally perpendicular to the base of the lower element and is in line with an opening of the lower element.

5. A connector as claimed in claim 4 wherein the arcuate segments of the lower 25 portion define an end wall, a recessed portion and an inner end wall facing the stud whose top is lower than that of the end wall.

6. A connector as claimed in claim 5 wherein the recessed portion defines a rounded convex saddle-shaped surface. 30

7. A connector as claimed in claim 5 or 6 wherein a vertically extending slot or keyway is defined in the inner wall facing the stud.

8. A connector as claimed in any preceding claim for linking between two closed 35 chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, wherein in use the lower element is 9 disposed vertically below the upper element in the assembled connector and wherein a series of bores extend through the upper and lower elements for receiving pins connecting the same and wherein at least two of the bores are oriented in a non-parallel axis to one another. 5

9. A connector as claimed in claim 8 wherein with respect to a notional horizontal plane passing through the centre of the assembled connector, the bores extend at an acute angle to that plane.

10 10. A connector as claimed in claim 9wherein the acute angle is from 30 to 600 to the plane.

11. A connector as claimed in any preceding claim wherein the connector is a vertical or block chain connector 15

12. A connector as claimed in any preceding claim wherein the functionality of the connector is such that the connector can still function in a chain conveyor after failure of the upper element. 20

13. A vertical block chain connector for linking between two chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, wherein, in use, the lower element is disposed vertically below the upper element in the assembled connector, in which the functionality of the connector is provided such that the connector can still function in a chain conveyor 25 after failure of the upper element.

14. A connector for linking between two closed chain links comprising a lower element and an upper element configured to engage with the lower element to form the chain connector, wherein in use the lower element is disposed vertically below the 30 upper element in the assembled connector and wherein a series of bores extend through the upper and lower elements for receiving pins connecting the same and wherein at least two of the bores are oriented in a non-parallel axis to one another.