GB2338946A

GB2338946A - Chain conveyor flight bars

Info

Publication number: GB2338946A
Application number: GB9914225A
Authority: GB
Inventors: Peter Howard; Roger Harold Coleman
Original assignee: ADVANCED CONVEYOR TECHNOLOGIES
Current assignee: ADVANCED CONVEYOR TECHNOLOGIES
Priority date: 1998-06-29
Filing date: 1999-06-18
Publication date: 2000-01-12
Anticipated expiration: 2019-06-18
Also published as: GB9914225D0; GB2338946B; AUPP437098A0

Description

1 2338946 CHAIN CONVEYOR FLIGHT BARS

Field of the Invention

The following invention relates to flight bars or scraper bars of chain conveyors of the type typically used in the underground coal mining industry. Chain conveyors include an elongate pan having a smooth surface along which a pair of parallel chains are drawn. Attached to each chain there extends a plurality of transverse flight bars or scraper bars which slide along the smooth surface of the pan upon being drawn therealong by the chains. Each flight bar is attached to both of the chains.

Two piece scraper bars or flight bars are known to include a pair of overlapping components which, in combination, extend throughout the width of the pan and are held together by means of threaded fasteners having their longitudinal axes extending parallel to the direction of extent of the conveyor chains. That is, the threaded fasteners extend transversely of the flight bars in a horizontal direction. The individual components of the flight bar must clamp onto the pair of chains or onto themselves so as to secure the bar to the chains. As the threaded fasteners extend in a direction normal to that at which a clamping force of the components onto the chain is desired, little chain clamping force results. Accordingly, the chain links work loose of the flight bars in time.

Disclosed in European Patent Publications 0 079 192 and 0 270 702, German Patent Specifications 2031927, 3525994 and 3016151, USA Patent 4,383,603 and

Australian Patent 561891 are chain conveyors including flight bars.

The above-discussed chain conveyors and in particular the flight bars employed therein do not provide well for wear of the flight bars, that is the flight bars require frequent replacement. Still further, wear of the flight bars also causes wear of the drive sprockets and again their replacement.

Object of the Invention It is the object of the present invention to overcome or substantially ameliorate the above disadvantage and/or more generally to provide an improved chain conveyor flight bar.

2 Disclosure of the Invention

There is disclosed herein a flight bar for a chain conveyor having a pair of generally parallel driven chains, the bar having:

an upper bar member to extend generally transverse of the chains; a lower bar member to engage the upper bar member, the lower bar member being provided to extend generally transverse of the chains and to slide over a chain conveyor;and means to secure the two member together so as to attach the two members to the chains, and wherein the upper member has an elongated central portion with downwardly extending projections at each end extremity, with said lower bar being located between said end extremities so as to engage a conveyor pan.

There is further disclosed herein a flight bar for a chain conveyor having a pair of driven chains, the flight bar having:

an upper bar member to extend generally transverse of the chain; a lower bar member secured to the upper bar and also to extend generally transverse of the chain; means securing the members together so that in use the bar is secured to the chains, the chains passing between the members; and wherein the bar members have cooperating recesses to accommodate the chains passing between the bar, the cooperating recesses including a pair of recesses, each pair of said recesses being provided to accommodate a vertical link of a respective one of the chains, each pair of recesses including a pair of trailing and a pair of leading recess portions, with the leading recess portions extending inwardly of the bar, a greater distance than the trailing recess portions.

3 Brief Description of the Drawings

Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:

Figure I is a schematic side elevation of the flight bar of a chain conveyor; Figure 2 is a schematic perspective view of the upper bar member of the flight bar of Figure 1; Figure 3 is a schematic top plan view of the flight bar of Figure 1; Figure 4 is a schematic top plan view of a further flight bar, similar to that of Figure 3; Figure 5 is a schematic side elevation of the flight bar of Figure 4; Figure 6 is a schematic bottom plan view of the flight bar of Figure 4; Figure 7 is a schematic sectioned end elevation of the flight bar of Figure 4, sectioned along the line 7-7.

Figure 8 is a schematic top plan view of a further flight bar; Figure 9 is a schematic side elevation of the flight bar of Figure 12; and Figure 10 is a schematic bottom plan view of the flight bar of Figure 12.

Figure 11 is a schematic top plan view of the upper bar member of the flight bar of Figure 12; Figure 12 is a schematic section side elevation of the upper bar member of the flight bar of Figure 8; and Figure 13 is a schematic sectioned end elevation of the upper bar member of Figure 9, sectioned along the line 10-10.

Description of the Preferred Embodiments

In Figures I to 3 of the accompanying drawings there is schematically depicted a flight bar 10 of a chain conveyor, the flight bar 10 being adapted to engage a pair of generally parallel coextensive chains 11. The chains 11 are driven so that the bar 10 is dragged over an elongated pan of a chain conveyor.

4 The bar 10 includes an upper bar member 12 which is secured to a lower bar member 13 by threaded fasteners which pass through passages 14 in the member 12 to engage nuts 15. Each threaded fastener will include a head located within shaped recess 16, so that the head of each threaded fastener is engaged within the bar member 13.

When the threaded fasteners are tensioned, the bar member 13 is secured to the bar member 12, so that the flight bar 10 is also secured to the chains 11.

The upper bar member 12 has an elongated central portion 17, provided at each extremity with a downwardly extending projection 18. The lower bar member 13 is located between the extensions 18.

The chains 11 have horizontally oriented links 19 joined by vertically oriented links 20. The links 19 pass through the bar member 12 via a pair of generally parallel passages 21 which are joined by leading and trailing recesses 22. The vertical links 20 are associated with leading recesses 24, and trailing recesses 23.

Preferably the upper bar 12 is provided with recesses 25 to receive nuts 15.

The chains 11 are driven in the direction of the arrow 26 to that the flight bar 10 is driven by engagement of the vertical links 20 in the recesses 23.

The lower bar 13 engages the above-mentioned pan, in conveying mined material along the pan. When the bar 13 becomes worn, it can be replaced thereby enabling reuse of the bar 12.

Figures 4 to 7 of the accompanying drawings schematically depict a modification of the flight bar of Figure 10, with the reference numerals employed with reference to Figures 1 to 3, also being used in Figures 4 to 7.

In Figures 8 to 13 there is schematically depicted a further flight bar. The same reference numerals have been employed in these figures.

In the embodiment of Figures 8 to 14, the leading recesses 24, and trailing recesses 23 include upper recess portions 26 and 27, with the recess portions 26 having drive surfaces 28 which engage the leading face of the links 20. More particularly, the leading recesses 24 extend into the bar 10, a greater distance am the trailing recesses 23. That is, the recesses 24 extend a distance 29 into the bar 10, while the recesses 23 extend a distance 30. The distance 29 is greater than the distance 30. In this configuration the web 31 between the recesses 23 and 24 is spaced rearwardly (relative to the direction of movement 26) with respect to the central plane 32 of the bar 10, so that the portion 33 of the web 31 rearwardly of the plane 32 is deeper than the portion 34 forward of the plane 32.

In the embodiment of Figures 8 to 14, there is one vertical passage 14 to receive a threaded fastener, and two horizontal passages 14 which also receive a threaded fastener. In this embodiment the upper bar member 12 has a recess 35 to receive an eyelet 36 of the lower flight bar 13. The portion of the passage 14 in the eyelet 36 aligns with the portions of the passage 14 formed in the upper bar member 12. A similar construction is provided on the other side of the flight bar 10.

It should be appreciated that in respect of the embodiment of Figures 8 to 13, it could be constructed in a similar manner to the flight bars of Figures 1 and 4, that is with the lower bar members 13 extending between two downwardly extending projections, such as the projections 18 of Figures 1 and 4.

The embodiment of Figures 8 to 14 provides a particular advantage in respect of ameliorating problems associated with the drive sprockets engaging the bar as the bar wears. Typically, the surface 28 will wear and eventually permit engagement of the bar 10 with the drive sprocket. To ensure that the bar 10 does not engage the next forward link 20, the distance 29 is increased.

6 The claims defining the invention are as follows:

1. A chain conveyor flight bar having a pair of generally parallel driven chains, the bar having:

2. A chain conveyor flight bar having a pair of driven chains, the flight bar having:

an upper bar member to extend generally transverse of the chain; a lower bar member secured to the upper bar member and also to extend generally transverse of the chain; means securing the members together so that in use the bar is secured to the chains, the chains passing between the members; and wherein the bar members have cooperating recesses to accommodate the chains passing between the. bar, the cooperating recesses including a pair of recesses, each pair of said recesses being provided to accommodate a vertical link of a respective one of the chains, each pair of recesses including a pair of trailing and a pair of leading recess portions, with the leading recess portions extending inwardly of the bar, a greater distance than the trailing recess portions.

3. The chain conveyor flight bar of claim 1, wherein the bar members have cooperating recesses to accommodate the chains passing through the bar, the cooperating recesses including a pair of recesses, each pair of said recesses being provided to accommodate a vertical link of a respective one of the chains, each pair of 7 recesses including a pair of travelling and a pair of leading recess portions, with the leading recess portions extending inwardly of the bar, a greater distance than the travelling recess portions.

4. The chain conveyor flight bar of claim 2, wherein the upper member has an elongated central portion with downwardly extending projections at each end extremity, with said lower bar member being located between said end extremities so as to engage a conveyor pan.

5. A chain conveyor flight bar constructed substantially as hereinbefore described with reference to, and as illustrated in, Figures I to 3 or Figures 4 to 7 or Figures 8 to 13 of the accompanying drawings.