A control for a crane boom mounted on a self-propelled vehicle for pivoted movement about vertical and horizontal axes. Connecting means cooperating with said first and second control means are provided for actuating one of said first and second control means upon actuation of the other to maintain the free end of the boom in a predetermined vertical or horizontal plane. Crane control includes at least one cable for lifting a load, wherein at least one sensor unit is provided for determining a cable angle relative to the direction of gravitational force. Furthermore, there is shown a crane control for driving the positioners of a crane which includes at least one first and one second strand of cables for lifting the load, with a load oscillation damping for damping spherical pendular oscillations of the load, wherein first and second sensor units are provided, which are associated to the first and second strands of cables, in order to determine the respective cable angles and/or cable angular velocities, and the load oscillation damping includes a control in which the cable angles and/or cable angular velocities determined by the first and second sensor units are considered. The crane control drives the positioners of the crane. A luffing gear and a slewing gear are provided as positioners. The embodied hoisting mechanism has a hoisting cable, a hoisting-cable drive, a frame and a jib that can be topped. Hoisting-cable drive means form a path for the hoisting cable. A displaceable hoisting-cable guide is used with the hoisting cable so that the displacement of the displaceable hoisting-cable guide changes the length of the path. The displaceable hoisting-cable guide has an associated first hydraulic component with a first chamber that can be connected to a second hydraulic component with a second chamber of variable volume. A pressure source is coupled to the second hydraulic component in order to maintain a substantially constant hydraulic pressure in the second chamber. A pressure-limiting valve assembly, which is partially actuated by a topping-means loading sensor, is incorporated in the connection.
Milling is the complex shaping of metal (or possibly other materials) parts, by removing unneeded material to form the final shape. It is generally done on a milling machine, a power-driven machine that in its basic form is comprised of a milling cutter that rotates about the spindle axis (like a drill), and a worktable that can move in multiple directions (usually three dimensions [x,y,z axis] relative to the workpiece, whereas a drill can only move in one dimension [z axis] while cutting). The motion across the surface of the workpiece is usually accomplished by moving the table on which the workpiece is mounted, in the x and y directions. Milling machines may be operated manually or under computer numerical control (cnc), and can perform a vast number of complex operations, such as slot cutting, planing, drilling and threading, rabbeting, routing, etc. Two common types of millers are the horizontal miller and vertical miller.
