Patent GB-789923-A (GB)
Title: Improvements in loaders
IPC: E21D9/12
Filed: 1956-02-10
Abstract: 789,923. Endless conveyer loaders. ATLAS COPCO AKTIEBOLAG. Feb. 10, 1956 [Feb. 15, 1955], No. 4259/56. Class 78 (1). [Also in Group XXXI] A portable conveyer loader adapted to have its loading head resting on the ground, and including an endless conveyer and a pair of powerdriven feeder fingers 18 for moving material from around the head into the path of the conveyer, is mounted on a pair of power-driven traction-wheels 40 situated close to the centre of gravity of the loader, so that the loader may be manually tilted about the axis of the wheels and manually guided during operation by means of handles 77 adjacent its discharge end. In one construction, Figs. 1, 4, 5 and 8, the wheels 40 are secured to separate shafts 41 journalled in a housing 42 bolted to the conveyer framework. On the inner ends of these shafts are mounted axially slidable dog-clutch elements 44 normally urged by springs 49 into engagement with a mating element 47 forming part of a driven gear-wheel 45, but which may be manually withdrawn from such engagement by withdrawal members 51 actuated through a camoperated lever assembly 52, 56, 58 by manipulation of a handle 60. The driven wheel 45 forms part of a gear train which is driven by a reversible compressed-air motor 62 controlled by a valve 72 having forward, stop and reverse positions. The conveyer consists of a pair of chains 7 carrying scrapers, the chains being driven by a pair of head sprockets 10 driven by a compressed-air motor 11. A pair of spring- actuated tensioning sprockets 14 is provided. The fingers 18 are pivotally mounted on oppositely rotating discs 20 mounted flush with the loading head and have their rear portions 30, which are of channel form, slidably engaged with blocks 31 which are pivoted on eccentric supports 33 in the loading head to enable the paths of the fingers to be adjusted. The forward portions 34 of the fingers are pivoted to the remaining portions of the fingers on horizontal pins 35 to allow them to rise upon meeting heavy resistance. The discs 20 are driven through separate chain drives 23, each provided with spring tensioning means from sprockets situated adjacent the ends of a transverse connecting shaft 24, these sprockets being driven by bevel gearing from this shaft. Resilient sections 28 are incorporated in the connecting shaft 24 to relieve strain, shaft 24 being driven through further chain gearing 27 from a compressed-air motor 26. The supply of air to the motors 11 and 26 is controlled by a remotecontrolled valve 66, Figs. 1 and 8. Valve 66 is constructed either as disclosed in Specification 654,112, [Group XXIX], or, as shown in Fig. 8, it comprises a diaphragm 94 normally urged by the supply pressure applied through a pipe 70 controlled by a cock 76 to the chamber 93, but raisable by the pressure in supply pipe 65 upon closure of cock 76 to admit the air through pipes 67, 68 to the two motors 11 and 26. In a second construction, Fig. 11, the traction wheels 40 are freely mounted on stub-shafts 84 secured in the conveyer frame and are independently driven by separate compressed air motors 80 through belts 81 driving pulleys 82 formed on the wheels 40. The motors 80 together with their driving pulleys are mounted on pivoted adjustable levers 83 so that the wheels may be de-clutched by slackening the belts 81. Compressed air cylinders may alternatively be used for slackening the belts.