GB1414152A - Mining machine - Google Patents

Abstract

1414152 Bucket chain excavators GOSUDARSTVENNY NAUCHNO - ISSLEDOVATELSKY I PROEKTNY INSTITUT UGOLNOI PROMYSHLENNOSTI UKRNHPROEKT 9 Nov 1972 51707/72 Heading E1F In a bucket wheel excavator, a reduction gear 5, which links an electric motor 4 and a bucket chain drive drum 1, has a housing 8 which is engaged by the reduction gearing and which must be restrained from rotation to allow power transmission; a resilient restraining means allowing limited oscillations of the housing to occur in response to any forces acting on the buckets, and a flywheel being drivably connected to the housing to further control these oscillations. Pressure rollers 9, connected by levers 11 to a pneumatic cylinder 12, engage recesses 10 on the housing and gearing 19 links the housing to the shaft of a flywheel 17; the whole forming an oscillating system whose natural frequency is selected to be as near as possible to the frequency of any pertubations acting on the chain by adjusting the damping force of the cylinder 12 and/or the moment of inertia of the flywheel. If the buckets encounter an immovable obstacle the housing will rotate to an extent that the rollers 9 will leave the recesses 10; in this case levers 12a, 13, will operate a switch 30 to exhaust cylinder 12 (allowing free rotation of the housing 8) and to turn off the motor 4. In further embodiments: a number of separate flywheels are mounted on the shaft 18 and each can be selectively engaged or disengaged from the shaft (Figs. 4, 5, not shown); the flywheel mass can be radially adjusted with respect to the shaft 18 (Fig. 6, not shown); and a motor and reduction gearing system can be provided on each side of the drum (Fig. 7, not shown).