Abstract: A transition for electrical well cable through the wellhead barrier of an underground well leads to an electrical power cable connected to an above-ground electrical power source, where the only connection between the electrical well cable and the electrical power cable is formed inside the wellhead barrier, between approved primary and secondary seals. A drain or vent to the atmosphere is also located between the seals.

Abstract: The tool and method for preparing for insertion into an eye an intraocular lens formed of a compressible material includes an elongated hollow chamber with an inlet end and an outlet end. An intraocular lens formed of a compressible material is extruded to a smaller size that fits in the elongated chamber by a compresser which includes an outlet adapted to be aligned with the inlet end of the elongated chamber. The extruded intraocular lens is pushed through the elongated chamber from the inlet end through to the outlet end.

Abstract: A battery changing apparatus for replacing a spent battery with a charged one on an electrically powered vehicle including a support with at least two battery support sections for supporting batteries adapted for use on an electrically powered vehicle. A spent battery is removed from the vehicle and transferred to one of the support sections. The relative positions of the apparatus for removing and transferring the battery and the support can be changed so that a charged battery can be removed from another support section. The apparatus for removing and transferring the battery can remove the charged battery from the other support and transfer it to the vehicle.

Abstract: A chuck mechanism for a raise drill includes a rotatable drive shaft, drill pipe and a chuck for engaging the drill pipe co-axial with the drive shaft and transmitting torque from the drive shaft to the drill pipe. The drive shaft is rotatably coupled to the chuck with relative axial movement allowed. First spaced apart cooperating contact surfaces between the drive shaft and the chuck can be brought together for transmitting axial force from the drive shaft to the chuck in the downward drilling direction. Second spaced apart cooperating contact surfaces between the drive shaft and chuck can be brought together for transmitting axial force from the drive shaft to the chuck in the upward raise drilling direction. The drive shaft and chuck move axially relative to each other when contact is switched from the first to second contact surfaces or vice-versa. The second pair of contact surfaces are shaped and dimensioned for allowing relative angular movement therebetween when the drill pipe is deflected laterally.

Abstract: The invention is an improvement for a combination mining machine and roof bolting apparatus in which the roof bolting mechanism is pivotable and can be used to install roof bolts in more than one location without moving the mining machine. The improvement is a pivotable canopy which pivots independently of, but in association with, the bolting apparatus. It comprises a canopy shield pivotably and cantileveredly mounted on the upper section of a telescopically-extensible mast. The telescopic mast absorbs all the moment loads, while the hydraulic extension cylinder disposed interiorily of the mast incurs only axial compressive loading.

Abstract: A plastic chain has a link which includes two sections formed of molded thermoplastic material. One end of each link section includes a first opening and is shaped so that when the link sections are joined, the ends will be spaced apart and the first openings aligned. The other end of each section includes a second opening. First and second mating means cooperate to join the other end to form a link. The ends with the first openings are spaced apart a sufficient distance to accommodate at least a portion of the joined other ends of an adjacent similarly-shaped link so that the first openings can be aligned with the second openings in the adjacent link to receive a link pin which is in the form of a hollow tube with a manually releasable resilient latch.

Abstract: An improved mining machine including apparatus for cleaning particle-laden gas, of the type which includes a duct in which liquid droplets are introduced into particle-laden gas flowing through the duct, a demister in the duct for removing liquid and particles from gas which moves through the duct. The improvement includes at least one curved flow path in the demister for causing the gas to change direction and a liquid collection surface defining the bottom of the demister. Collected liquid is removed from the liquid collection surface. A liquid collection barrier with an aerodynamically curved upper surface is located downstream from the curved flow path and defines the downstream end of the liquid collection surface, the barrier extending the width of the flow path.

Abstract: An improved apparatus for cleaning particle-laden gas, of the type which includes a duct where liquid droplets are introduced into particle-laden gas flowing through the duct, a demister in the duct for removing liquid and particles from gas which moves through the duct. The improvement includes at least one curved flow path in the demister for causing the gas to change direction and a liquid collection surface defining the bottom of the demister. Collected liquid is removed from the liquid collection surface. A liquid collection barrier is located downstream from the curved flow path and defines the downstream end of the liquid collection surface, the barrier extending the width of the flow path.

Abstract: A method for performing strength tests on material to be mined includes the steps of preparing a flat surface on the material to be tested, forming one or more grooves in the flat surface, impacting the flat surface with a test device at a predetermined angle and at a predetermined force which is at least as great as that necessary to break out material located between the impact point and groove, repeating the preceding step at a predetermined distance from the first impact, at substantially the same force and at substantially the same angle.An impact guide and sample collector guides the test device toward the test surface at a predetermined angle and collects material broken out during the test.

Abstract: A hydraulic system for a drilling apparatus where torque is transmitted to drill pipe, a plurality of thrust cylinders move the torque transmitter back and forth along the drill pipe axis, and a hydraulic motor supplies torque to the torque transmitter, includes: a first drive pump for supplying hydraulic fluid to the motor; a first valve between the first drive pump and motor for selectively controlling the direction of fluid flowing to the motor; a second drive pump for selectively supplying fluid either to the thrust cylinders or motor; a second valve between the second drive pump, on one side, and the thrust cylinders and motor, on the other side, for selectively diverting fluid flow from the second pump either to the thrust cylinders or the motor; a third pump for supplying fluid to the thrust cylinders; a third valve connected between the second and third pumps, on one side, and the thrust cylinders, on the other side, for selectively controlling the direction of fluid flowing to the thrust cylinders; a

Abstract: The invention is a unique connector for joining the juxtaposed ends of the shafts of two adjacent conveyor idler rolls. The shaft ends are provided with diametrically extending pivots. The connecting link comprises a continuous or endless loop of relatively rigid high strength material folded over to form two pairs of spaced but parallel gudgeons, each pair of gudgeons forming a clevis. One clevis loopingly or pivotably engages the pivots attached to one idler shaft, and the other clevis similarly engages the perpendicularly aligned pivots attached to the other shaft. In one embodiment, a trunnion nut having colinearly extending pivot stubs and a threaded central opening, is screwed onto the end of each shaft. Optionally, a flexible grease tube can be passed from one shaft end through the connector to the other shaft end to provide flow-through lubrication capability.

Abstract: An improved connecting link for a mining chain includes two half links and means for fastening them together. Each half link has a laterally extending bore for receiving the link pin at one end of the chain. At least one of the half links has a laterally extending wedge-shaped projection pointed toward the other half link, while the other half link has a mating recess with inclined walls corresponding to converging walls of the wedge-shaped projection. When assembled, the projection of the one half link snugly engages the recess of the other half link such that the pulling forces in the chain are transmitted directly from one half link to the other rather than through the fastening means. The fastening means can be removed even when the chain is operated between adjacent chains.

Abstract: A fume extraction assembly comprises an elevated canopy adapted to collect fume; and elongated outlet means offset from an apex of the canopy and having gas flow characteristics compensating for a tendency to uncontrolled extraction rates along said outlet means.

Abstract: A control circuit for an electrostatic precipitator, in which an analogue voltage indicative of the desired precipitator electrode potential is stored and periodically increased in the absence of any condition, notably a falling electrode potential, that the desired voltage is excessive in which case the stored potential is reduced.

Abstract: An improved rotating disc-type gathering head suited for use with underground mining machines includes at least two gathering discs mounted for rotation on an inclined apron in positive engaging relationship at their point of tangency. One of the discs is rotatably driven, preferably by means mounted above the apron. The second disc is rotated in the opposite direction by the first disc to provide the desired flow of mined material. In the preferred embodiment the discs have peripherally disposed intermeshing gear teeth, and the drive means comprises a pinion gear in peripheral engagement with the first disc. Additional gathering discs can be added without complicating the simple mechanical drive system below the apron.