GB2340912A

GB2340912A - A chain for scraper chain conveyors

Info

Publication number: GB2340912A
Application number: GB9915393A
Authority: GB
Inventors: Gert Braun
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-07-16
Filing date: 1999-07-02
Publication date: 2000-03-01
Anticipated expiration: 2019-07-02
Also published as: GB9915393D0; DE19831994A1; GB2340912B; DE19831994B4

Abstract

A chain for scraper chain conveyors, wherein the vertical links (1) are constructed as cam links comprising cam link bends (4) and comprise a flattened surface (11). The cam link bends (4) comprise a pusher edge (6) which is adjoined by a pivoting bend (7) which corresponds to an attachment heel of a pusher(9) which acts between two adjacent vertical links (1) and which specifies the setting angle of the cam links (1) to prevent kinking.

Description

2340912 "A Chain for scraper chain conveyors" This invention relates to a

chain for scraper chain conveyors, having vertical links and horizontal links which each comprise chain link limbs and chain link bends which join the chain link limbs, wherein the vertical links comprise flattened chain link limbs.

A round link chain for mining conveyors is known in which it is only on their parallel chain link limbs that the vertical links have a cross-section which is flattened in relation to their round cross-section, whilst their chain link bends which join the chain link limbs have a circular cross section (see DE-PS 32 34 137).

Furthermore, a chain is known which comprises vertical and horizontal chain links and in which the vertical and horizontal links have a different pitch and the chain articulation, which is transverse to the longitudinal direction of the chain, extends substantially linearly over at least the chain link width. In this respect, what is put into effect is not a round link chain, but is a special construction comprising rectangular horizontal links, as it were (see DE-OS 32 35 474).

These known chains strictly do not function as chain conveyors for bulk materials such as coal, ore, rock or the like. This is unsatisfactory. The present invention comes into effect here.

A basic object of the present invention is to create a chain of the form of construction described at the outset which during its progressive movement in a conveyor pan provides assistance to I pushers which are jointly conveyed therein by also moving the material being conveyed, whilst effecting a reduction in frictional forces and an enhancement of operational reliability.

According to the present invention, there is provided a chain for scraper chain conveyors, having vertical links and horizontal links which each comprise chain link limbs and chain link bends which join the chain link limbs, wherein the vertical links comprise flattened chain link limbs, wherein the vertical links are constructed as cam links comprising cam link bends, and that the cam link bends comprise a pusher edge associated with the pan base of the scraper chain conveyor and a pivoting bend which adjoins the pusher edge(s) and which corresponds to an attachment heel of a pusher which acts between two ad acent vertical links or which corresponds to an engaging tooth of a chain star wheel and which delimits a predetermined setting angle range.

The invention stems from the recognition that a chain conveyor can assist the operation of its pushers if the vertical links comprise a pusher edge which slides on the pan base, as it were, and which performs a pushing function with respect to the material which is being conveyed and which is to be carried away. Frictional forces are reduced at the same time, because the cam links according to the invention slide on the pan base, as it were, due to the pusher edge which advances in the direction of conveying. Moreover, the cam links are prevented from being pushed on to the material being conveyed and then jamming. In contrast to a classical round link chain, this in turn results in reduced driving forces. An increased level of operational reliability is achieved, because the pivoting bends of the cam links cooperate with correspondingly constructed joint faces on the attachment heels of the pushers in such a way that kinking phenomena are prevented. This is because the pivoting bends, which are convex as it were, on the cam links, and the joint faces, which are concave as it were, on the attachment heels of the pushers, are matched to each other so that a predetermined setting angle can never be exceeded.

This setting angle is preferably less than 30', but in any event is not greater than 30". Other advantages which are achieved by the invention are that, despite the fact that chains and pushers are always becoming heavier, the specific loading of the chain conveyor towards the pan base is nevertheless reduced due to an increased area of contact, and wear is consequently minimised.

This applies in particular to an embodiment of the invention according to which the cam links or vertical links have a constant cross-section, as do the horizontal links also, and also have a flat comprising boundary edges on the outside of the link and a round, e.g. circular inner face on the inside of the link. In this respect, a chain conveyor is put into effect in which the vertical links or cam links have contact faces on the outside which have comers, as it were, and which otherwise have a 3/4 round cross-section. Moreover, the cam links ensure that the chain conveyor cannot become kinked in the region of the chain star wheel, particularly in the region of the chain-turning drive, even if it leaves the driven chain star wheel. For conventional round link chains, kinking phenomena such as these frequently result in chain breakages.

Other preferred features of the invention are listed below. Thus the invention provides for the pusher edge of the cam links to be advanced towards the adjacent horizontal links with respect to the vertical alignment of the corresponding engagement faces of the cam links and the horizontal links. This results in a particularly long contact face of considerable area for the vertical cam links on the pan base, and consequently results in a corresponding reduction in specific loading. Moreover, a very fine layer can be formed between the cam links and the pan base, particularly if the material being conveyed is coal, which layer performs the function of a sliding layer, as it were, and significantly reduces chain wear (which would otherwise result from steel on steel). In this connection, it is further recommended according to the invention that the link cross-section of the cam links is larger than that of the horizontal links with regard to the link width thereof. Furthermore, the cam links and the horizontal links can consist of different materials, and in particular can consist of different steels, whereby fretting, as it were, is prevented between the cam links and the horizontal links, as it is between the earn links and the attachment heels of the pushers and between the teeth of the chain star wheels. Retaining stirrups, which are fixed to the pushers, generally fit below the pushers, or the attachment heels thereof, and the respective horizontal links into which the attachment heels fit between the vertical links. In this connection, it is recommended according to the invention that the retaining stirrups and the pusher flanks on both sides form a continuous scraper edge on the pan base, so that the material being conveyed is carried away in an improved, perfected manner in this respect also.

The invention is explained in greater detail below with reference to the drawings, which merely illustrate an example of an embodiment, and where:

Figure 1 is a side view of a portion of a chain according to the invention; Figure 2 illustrates the subject of Figure 1 showing an angled vertical link or cam link, where the chain link limb of the adjacent horizontal link which joins the cam links has been omitted from the drawing; 1 1 - J -S- Figure 3 is a plan view of the subject of Figure 1; Figure 4 is a partial view of a pusher, showing the respective horizontal link and a retaining stirrup which fits under the attachment heel of the pusher; and Figure 5 is a cross-section through a cam link.

The Figures illustrate a chain for scraper chain conveyors, having vertical links 1 and horizontal links 2 which each comprise chain link limbs 3 and chain link bends 4 which join the chain link lirnbs, wherein the vertical links 1 comprise flattened chain link limbs 3. The vertical links are constructed as cam links 1 comprising cam link bends 4. The cam link bends 4 each comprise a pusher edge 6 associated with the pan base 5 of the scraper chain conveyor and a pivoting bend 7 which adjoins the pusher edge(s) 6 and which corresponds to an attachment heel 8 of a pusher 9 which acts between two adjacent vertical links 1, or which corresponds to an engaging tooth of a chain star wheel, and which delimits or allows a predetermined setting angle range. The expression "corresponds to" means that the convex pivoting bends 7 are associated with correspondingly concave joint faces 10 on the attachment heels 8 of the pushers 9. The maximum setting angle of the cam links 1 in relation to the horizontal links 2 is 3C.

The cam links 1 have a constant cross-section and have a flat comprising boundary edges 11 on the outside of the link and a round inner face 12, which is circular in the embodiment exemplified, on the inside of the link. The pusher edge 6 of the cam links 1 is advanced towards the adjacent horizontal links 2 with respect to the vertical alignment S of the corresponding -6engagement faces of the cam links 1 and the horizontal links 2. The link cross-section of the vertical links or cam links 1 is larger than that of the horizontal links 2 with regard to the link width B thereof. The cam links 1 and the horizontal links 2 consist of different materials.

Retaining stirrups 13 which are fixed to the pushers 9 fit under the attachment heels 8 of the pushers 9 and under the respective horizontal links. The retaining stirrups 13 and the pusher flanks 14 on both sides form a continuous scraper edge 15 on the pan base 5 of the conveyor pan in question.

1 11 -7

Claims

1. A chain for scraper chain conveyors, having vertical links and horizontal links which each comprise chain link limbs and chain link bends which join the chain link limbs, wherein the vertical links comprise flattened chain link limbs, wherein the vertical links are constructed as cam links comprising cam link bends, and that the cam link bends comprise a pusher edge associated with the pan base of the scraper chain conveyor and a pivoting bend) which adjoins the pusher edge(s) and which corresponds to an attachment heel of a pusher which acts between two adjacent vertical links or which corresponds to an engaging tooth of a chain star wheel and which delimits a predetermined setting angle range.

2. A chain according to Claim 1, wherein the setting angle of the cam links in relation to the horizontal links is:5 3T.

3. A chain according to Claims 1 or 2, wherein the cam links have a constant cross-section and have a flat comprising boundary edges on the outside of the link and a round, e.g. circular, inner face on the inside of the link.

4. A chain according to any one of Claims 1 to 3, wherein the pusher edge of the cam links advanced towards the adjacent horizontal links with respect to the vertical alignment (S) of the corresponding engagement faces of the cam links and of the horizontal links.

5. A chain according to any one of Claims 1 to 4, wherein the link crosssection of the cam -'I 1 links is larger than that of the horizontal links with regard to the link width (B) thereof.

6. A chain according to any one of Claims 1 to 5, wherein retaining stirrups which are fixed to the pushers fit under the attachment heels of the pusher and under the respective horizontal links, characterised in that the retaining stirrups and the pusher flanks on both sides form a continuous scraper edge on the pan base.

7. A chain for scraper chain conveyors, substantially as hereinbefore described with reference to the accompanying drawings.

8. A scraper chain conveyor provided with a chain as defined in any preceding Claim.