GB570756A - Improvements relating to trench excavating machines - Google Patents

Abstract

570,756. Endless-chd;in conveyers. AVELING-BARFORD, Ltd., and WILCOCK, C. M. Sept. 28, 1943, No. 15899. [Class 78 (i)] [Also in Group XXI] In a trench-excavating machine comprising a pivoted boom carrying an endless digging-chain adjustable to and from the area to be excavated while the machine is in motion, two sets of tools are provided, one set breaking up the soil and the other set elevating the soil to the normal ground level where one or more transverselydisposed soil-gathering or banking elements entrain the soil upwardly to form a parapet beside the excavation.. As shown, a girder frame 1 is supported by narrow track front steering wheels 3 and wide track rear wheels 2, one rear wheel being manually adjustable vertically ; a bed plate 9 supports a motor 10 connected to a gear box 11 through a centrifugal clutch coupling 13. Adjustment of the frame 1 relative to the front wheels 3 is effected by a screw 102, Fig. 4, bearing on the steering post 7. The boom 24 is pivoted at 23 to depending brackets 22 and is adjusted vertically by means of a handwheel 37 acting through bevel gearing 34, 35, screw 32 and a cable 25 trained over pulleys 27 to 30: the boom may carry either one or two endless chains 43, each chain being provided with digging tines 53 and flat soil-gathering plates 54, the chains 43 being driven from the gear box 11 through chains 50, 45. In advance of the chain boom is a secondary frame comprising upper and lower pairs of spaced beams 57, 58, connected by struts 59, and supporting sprockets 60, 64, 65, around which passes a chain 69 carrying blades 70, the chain 69 being driven through reversing bevel gearing 72 to 74 and sprocket 66, and the blades 70 engaging the soil deposited by the digging chain or chains and carrying it sideways to form a parapet; a levelling attachment 75 is carried in advance of the off-side rear wheel 2 and finishes off the parapet. The beams 57 may be capable of being racked across the machine so that the parapet is formed on the opposite side; the handwheel 37 controlling the boom is then also transferable. The machine is advanced by means of a warping drum 19 driven by crank 77 and connecting rod 78 acting through a spring 90 to oscillate a lever 79 carrying a pawl 81 co-operating with a ratchet wheel 80 on the drum; a pawl 82 prevents return movement, while the throw of the pawl 81 is controlled by means of threaded rod 84, the drum 19 hauling on a cable which passes round a block 100 carried by a ground anchor &c. 101 and is attached to a draw-bar 21. Steering may be effected by a handwheel 92 acting through a spindle 93 carrying a worm 94 co-operating with a worm wheel 95; a bridle 97 normally engages a thrust collar 98 to hold the worm and worm wheel in mesh, but may be freed therefrom and engaged with a second collar 99 to hold the worm and worm wheel out of mesh when automatic alignment of the machine is required. The machine may be mounted on self-propelled endless tracks or wheels, and banking of the soil may be effected by rapidly reciprocating means.