Abstract: A conveyor-chain-drive gear-box and a chain-tensioning assembly comprising main gearing in the gear-box which includes a shaft carrying one of the gears, and auxiliary gearing outside the gear-box adapted to be driven by an auxiliary motor and having a gear wheel. An apertured side wall affords means through which the gear wheel and shaft may be removably connected together. An idler gear outside the gear-box is movable from a position in which it is out of engagement with the auxiliary gearing to an operative position in which it can transmit drive from the auxiliary motor to the auxiliary gearing. A housing is provided which is removably mounted on the side wall and within which are housed the auxiliary gearing and the idler gear.

Abstract: A locking device, for a member (for example a roller of a belt conveyor) mounted by way of a bearing on a shaft which member and shaft are relatively-rotatable, includes a heat-sensitive member. The heat-sensitive member normally holds the locking device out of its operative engagement and is disposed close to the bearing with part at least outside the shaft. The heat-sensitive member is made from a fusible material, or alternatively may comprise a bi-metallic element.

Abstract: This invention relates to a chain conveyor wherein the tension of the chain or chains thereof is controlled by a closed-loop servo system. The servo-system includes an electrically-operable servo-device. An electrical signal dependent on the torque of an electric motor driving the conveyor is applied to the servo-device for operation thereof to control a piston-and-cylinder device which is adapted to alter the distance between a chain-driving sprocket and another sprocket of the conveyor. The arrangement controls the tension of the or each chain at the point where the chain is just leaving the circumference of the first-mentioned sprocket, maintaining the tension at a constant value which may be near to zero under all conditions of operation.

Abstract: A belt conveyor of the extendible type wherein stools are provided which complete with respective upper and lower belt supporting elements can readily and reliably be introduced into the extendible portion of the conveyor during operation of the conveyor. Each such stool is provided with a gap at one side thereof and between its upper and lower elements to enable it to be inserted into the run of the conveyor in a direction transversely thereof. When so inserted the stool is disposed with its upper element above the lower run of the belt and with its lower element below the lower run of the belt.

Abstract: A driving and braking apparatus usable with a load such, for example, as an uphill belt conveyor.

Abstract: This invention relates to a mineral-cutting machine, the overall length of which can be substantially reduced, comprising a body and a ranging arm mounted for pivotal movement with respect to the body. A cutting device is supported on the ranging arm for rotation about an axis extending away from the ranging arm in a direction transverse to the intended direction of movement of the machine during a cutting operation. The cutting device is normally in a position at least partly beyond an end of the body during a cutting operation, and means are provided for moving the cutting device from said normal position at least partly beyond an end of the body to a position where it is at least substantially wholly alongside of the body.

Abstract: A power transmission including a motor, a "fixed-fill" fluid coupling and a gear box, at least the "fixed-fill" fluid coupling of which is liquid cooled.

Abstract: A braking apparatus for a rotary shaft connected to a load comprising brake shoe means for the shaft capable of limited angular movement about the shaft axis to cause release of the brake shoe means from a brake applied condition during application of starting torque to the shaft, and stop means operable during application of the brake shoe means to bring the shaft to rest, for preventing or reducing said limited angular movement. In this way the limited angular movement is eliminated during braking of the shaft to bring it to rest, whereby to provide substantially smooth braking, particularly when the shaft is operative on a load such as a conveyor having a long conveying belt.

Abstract: The invention concerns a scraper chain conveyor in which one or more endless chains drive a plurality of spaced scrapers along a conveying channel to convey loose material such as excavated rock. The invention comprises the provision on the or each chain of one or more wear pads at positions spaced from the scrapers to spread over a substantial area the wear due to the chain under tension bearing on parts of the conveyor channel having bends or irregularities.