IMPROVEMENTS IN SCRAPER CHAIN CONVEYORS

Abstract: A scraper chain conveyor has symmetrical scraper bars (12) connected to endless chains extending inboard of inwardly directed lips (64, 66) of the side flanges (8) of the pans (9). Each scraper bar includes a central portion (14) of a width slightly less than the distance between edges (10) of the upper lips (66) across the pan, and, secured thereto by bolts (52, 54), outer portions (16) extending as wings (34) into the side flanges to run on the bottom lip (64). The chain is retained on seatings (17) formed on the central portion (14) by retaining faces (32) formed on the outer portions (16).

Description: DE;SCEPTICIN "Improvements in Scraper Chain Conveyors". This invention relates to scraper chain conveyors and, more particularly, to scraper chain conveyors used to move particulate material, such as coal, along troughs or pans by means of scraper bars secured to endless conveyor chains spaced fran inwardly lipped flanges of the troughs or pans. According to the present invention there is provided a scraper chain conveyor having scraper bars secured to endless conveyor chains moveable along pans having inwardly lipped side flanges each scraper bar including a central portion and separate outer portions, the central portion having a width across the conveyor less than the distance between opposed edges of inwardly lipped flanges of an upper race thereof with seatings profiled to conform with a horizontally disposed link of chain, the outer portions being formed with retaining faces arranged to co-act with the seatings on the central portion and wings arranged to extend outwardly fran the central portion closely to adjoin the inner faces of the inwardly lipped side flanges and bolts respectively positioned inboard and outboard of the conveyor chain each extending through bores in the central portion and the associated outer portion are arranged to secure the central portion to the associated outer portion. The invention will now be described, by way of example, with reference to the accompanying, partly diagramnatic, draings, in which:- Figure 1 is a cross-sectional elevation of a portion of a scraper chain conveyor, showing part of a pan with corresponding parts of scraper bars in upper and lower races; Figure 2 is a plan view of the part of the scraper bar in the upper race; and Figure 3 is a plan view of the part of the scraper barin the lower race. The scraper chain conveyor includes a pair of endless chains 2 passing over sprocket wheels (not shown) and running in upperand lower races 4, 6 formed by inwardly .lipped side flanges 8 on pans 9 extending along the length of the conveyor. The endless chains are spaced inboard of the inner longitudinal edges 10, 11 of the inwardly lipped flanges and, at spaced intervals, have scraper bars 12 secured thereto. Each scraper bar consists of a central .portion 14 and, bolted to each end thereof, outer portions 16. The central portions 14 are of a width across the pan less than the distance between the opposed inner longitudinal ejgeslO of the upper race 4. At each end, the central portion 14 is formed with a seating 17 profiled to conform with a horizontally disposed link 18 of chain, a central land 20 engaging inner parts of the link and shoulders 22 engaging outer parts of the link. Recesses 24 are provided in the leading and trailing faces 26, 28 of the seating to accnndate the adjoining vertically disposed, links 30. Each outer portion 16 of the scraper bar includes a retaining face 32 arranged to abut and co-act with the land 20 and shoulders 22 on the associated seating 17 on the central portion 14 to secure the horizontally disposed link 18 of chain to the central portion. Outboard of the retaining face 32 each outer portion 16 extends as a wing 34 into the region bounded by the inwardly - lipped flange 8, the edge profile of the wing corresponding closely to the internal contours of the flange. Inboard and outboard of the seating 17, the central portion 14 and the outer portion 16 are formed with upright mating faces 36, 38 and 40, 42 lying in planes perpendicular to the direction of movement of the conveyor. Aligned bores 44, 46 are drilled in the central portion and outer portion inboard and outboard of the seating through the mating faces. The outer portion 16 is secured to the central portion 14 by tightening down nuts 48, 58 on bolts 52, 54 passed through the bores. The central portion 14 has a cross-section approximating to triangular with an upright leading face 26 and tapers down to a relatively narrow edge 58 adjacent the web 60 forming the floor of the pan 9. The wings 34 of the outer portions 16 are of generally trapezoidal cross-section and are profiled to contact the upper face 62 of the lower lip 64 of the inwardly lipped flange 8 in the lower race 6 - which has a greater lateral dimension than the corresponding lip 66 of the upper race more readily to support the scraper bars, and thus the conveyor chain, in the lower race. Th assemble a scraper bar onto the conveyor chains, the outer portions 16 are first positioned in the upper race 4 with the retaining faces 32 subjacent the respective horizontally disposed links 18 of chain. The central portion 14 is then positioned'in register with the outer portions and links, the width of the central portion across the pan 9 permitting passage past the opposed lips 10 of the inwardly lipped flanges, and the nuts 48,50 tightened down on bolts 52, 54 passed through the aligned bores 44, 46 in the central portion and outer portions. It will be appreciated that loading between the scraper bars and the endless chains is transferred from the seatings 16 on the central portions 14 to the horizontal links 18 and hence that the outer portions 16 are not subjected to great loading, since they serve only to retain the horizontal links 18 in position. Thus no undue loading is placed on the bolts 52, 54 and damage thereto is avoided - thereby facilitating their removal when replacement of a scraper bar is required.

Claims: ('AIMS 1. A scraper chain conveyor having scraper bars (12) secured to endless conveyor chains moveable along pans (9) having inwardly lipped side flanges (8) each scraper bar including a central portion (14) and separate outer portions (16), the central portion having a width across the conveyor less than the distance between opposed edges (10) of inwardly lipped flanges of an upper race (4) thereof with seatings (17) profiled to conform with a horizontally disposed link (18) of chain, the outer portions being formed with retaining faces (32) arranged to co-act with the seatings (17) on the central portion and wings (34) arranged to extend outwardly from the central portion closely to adjoin the inner faces of the inwardly lipped side flanges (8) and bolts (52, 54) respectively positioned inboard and outboard of the conveyor chain each extending through bores (44, 46) in the central portion and the associated outer portion are arranged to secure the central portion to the associated outer portion. 2. A scraper chain conveyor as claimed in Claim 1, characterised in that the dimension between the edges (10) of the upper lips (66) of the inwardly lipped side flanges is greater than the dimension between the edges (11) of the lower lips (64) and corresponds to the dimension of the central portions (14) of the scraper bars (12).

Inventors: MILLINGTON, MICHAEL JOHN
Applicants: PARSONS CONTROLS LIMITED
Application year: 1982
Main classification: B65G19
IPC codes: B65G19