Driving system for driving flexible elongate members, such as chains or scraper-chain assemblies, in mineral mining installations and method of operating

A method of operating a controller of a drive system for driving a haulage chain of a mining machine or a scraper-chain assembly of a conveyor, wherein said drive system includes a pair of spaced apart drive units, each unit comprising a coupler around which the chain or the scraper-chain assembly is drivably entrained;

• an electric asynchronous motor;
• a gearing assembly drivably interposed between the motor and the coupler;
• a multi-disc clutch operably associated with the gearing assembly to vary supportive torque exerted on a component of the gearing assembly to control drive torque transmitted through the gearing assembly;
• and
• an electrically-actuated valve operably associated with the clutch to provide a variable loading pressure to the discs thereof to control slippage and cause the variation in the supportive torque;
• the drive system further comprising at least one electronic controller for providing electrical control signals to the valves and sensor means for sensing operating parameters of the drive system including overloading and for providing measurement data to the controller;
• improved method of operating the controller to control the drive torque with the clutches and the valves to ensure a smooth start-up, to balance dynamic loading between the drive units and to disconnect the drive through the gearing assemblies in the event of a sensed overload wherein said method comprises:
• providing control signals to the valve during the start-up phase;
• operating the clutches to disconnect the drive initially through the associated gearing assemblies;
• allowing the motors to accelerate under load free conditions;
• and thereafter
• increasing the drive torque transmitted through the gearing assemblies progressively.