Abstract: The width of the clearance between a rotor with orbiting beaters and a pivotable impact plate of a machine for comminuting coal, rock, and like materials is adjusted by a computer which controls a reversible motor serving to pivot the impact plate relative to the path of orbital movement of the beaters. The computer causes the plate to pivot toward the path of the beaters when it receives a signal that the admission of material into the housing of the comminuting machine is interrupted and a converted acoustic signal denoting that the machine generates sounds which are indicative of completed evacuation of material from the housing. The direction of pivotal movement of the plate is reversed when the computer receives a series of converted acoustic signals or a single converted acoustic signal denoting that the width of the clearance has been reduced to zero, i.e., that the beaters actually strike the adjacent portion of the plate.

Abstract: A rotor which is to be used in an impact crusher has a set of coaxial discs with radially inwardly extending peripheral recesses for elongated beater bars which are parallel to the rotor axis and each of which extends into a discrete recess of each disc. The beater bars have male or female detent elements which cooperate with complementary female or male detent elements of the discs at the rear sides of the beater bars to prevent radially outward movements of the beater bars in actual use of the rotor. The front sides of the beater bars are engaged by wedges which are biased radially outwardly against the beater bars and against the respective discs by fluid-operated thrust elements in the recesses of the discs. Each thrust element has a piston rod which bears against the respective wedge and urges the wedge radially outwardly in the respective recess, and each thrust element reacts against an elongated rail which is installed in the deepmost portions of a set of aligned recesses of the discs.

Abstract: A drilling device for drilling a borehole and comprising a drilling tool, a drill pipe extending into the borehole for conducting a flow of liquid thereinto for generating an oscillating percussion force applied to the drilling tool, a longitudinally movable impulse tube located below a lower end of the drill tube, a throttle located between a lower mouth of the drill tube and an upper mouth of the impulse tube for controlling a ration of flow portion of the liquid outside and inside the impulse tube in accordance with longitudinal position thereof, and a spring-loaded thrust valve for controlling the flow of liquid inside the tube.

Abstract: A screw press comprises a housing having a spray casing and a screen casing arranged within the spray casing and forming an annular space therebetween, at least one press spindle located within the screen casing and forming a pressing space therebetween, the at least one press spindle having a plurality of wing members and at least one axial zone free of the wing members, and at least one dewatering member which is supported by the housing and located in the at least one axial zone in the pressing space between the spindle body and the screen casing, the at least one dewatering member being hollow and provided with a plurality of perforations and also having an outlet which opens into the annular space between the screen casing and the spray casing, the at least one dewatering member being arranged at a radial distance from the spindle and the screen casing, and at least one carrier holding the at least one dewatering member.

Abstract: A mobile crushing plant has an elongated frame with a front end portion connectable to a towing vehicle and a rear end portion supporting a comminuting machine which receives material to be crushed from a feeding unit having an inlet above the front end portion of the frame. When the plant is in use, the front end portion is detached from the towing vehicle and a first set of jacks in front of a pair of normally ground-contacting wheels is lowered into contact with the ground. A second set of jacks behind the wheels is then extended to lift the rear end portion by pivoting the frame about the lower end of the first set of jacks so that the inlet of the feeding unit is moved nearer to the ground and the comminuting machine is lifted above and away from the ground. A portion of the feeding unit is substantially horizontal when the front end portion of the frame is attached to the vehicle or when the crushing plant is in use.

Abstract: A spindle press comprises a housing with a circular cylindrical upper part and a lower part. A press spindle, which is drivable in a rotating manner via a drive pipe by a drive arrangement, is supported in an upper bearing and a lower bearing of the housing so as to be rotatable. A spindle body of the press spindle carries worm wings on the outside and compressor blades farther above, which all extend in the vicinity of a screen casing of the upper part. The screen casing is enclosed at a distance by a spray casing and provided with holes for pressed out fluid only from the compressor blades down. The spindle body also comprises perforations for the pressed out fluid only from the compressor blades down. Above the compressor blades a helically constructed front wall is welded in between an annular wall and the screen casing which is unperforated at that point. On the lower side of the front wall, wet pulp arrives tangentially through a filling opponent of the upper part.