Abstract: In a lifting gear comprising a lifting cable and two blocks, e.g. the upper trolley block and the lower hook block, respectively, of a hoisting crane, the number of cable parts, in which the lower block is hanging, is changed, in order to increase or decrease the lifting capacity, by means of a cable catching means being arranged on the lower block, which catching means is capable of catching (or disengaging) a cable part running horizontally in the upper block, which cable part is pulled down as two further parts with the catching means and at ground level laid under a further rope pulley of the lower block. Reblocking to fewer cable parts is carried out in the reverse order.

Abstract: A mucker for declined shafts supported on non-trackbound wheels and including a mucking assembly pivotally supported at the forward extremity of the machine frame and carrying a bucket for transverse pivotal movement for loading a skip. The mucker includes a built-in winch, and legs hydraulically extendable to the hanging wall and foot wall for anchoring purposes.

Abstract: A locking device for a holding door on an elevator shaft including a barrier member that is interconnected to a locking arm, said locking arm being alternately engageable and disengageable with a stop means so that the barrier member can only be moved out of way of the holding door when the elevator is adjacent to the holding door.

Abstract: An electromagnet comprises a coil core of ferro-magnetic material having a coil wound around the core. The coil is supported by a bobbin. The coil core is elongated, and the winding of the coil surrounds the core in its longitudinal direction, so that a homogeneous magnetic field extending between the longitudinally running end surfaces of the coil core is obtained along the length of the whole coil core. A touch free influence of magnetic field controlled means, such as reed switches, positioned along the length of the coil at one of its long sides provided with a winding being obtained, so that for influencing, said means can take a position relative to the magnet within a considerable margin determined by the length of the long sides of the magnet.

Abstract: At a rock drill, preferably most forwardly on its frame, a magazine with drill bits is arranged. When a drill bit has been worn such that it must be exchanged, the drill rod is retracted so much that the worn drill bit arrives at the magazine. By special means at the magazine the worn bit is unscrewed from the rod and replaced by a new bit from the magazine.

Abstract: The valve is adapted to close against the force of a bias spring in response to a substantial increase in the pressure drop through restricted by-pass passages in the valve when a hose is ruptured on the outlet side of the valve. The restriction of the by-pass passages is adjustable by rotation of an internal adjustment ring to thereby determine the flow rate at which the valve is actuated.

Abstract: A tube for sticking stripformed drains into the ground has a predetermined fixed profile of rhombic cross section made by pressing two opposite corners of a square tube towards each other.

Abstract: A composite transfer device for conveying material used in the construction of high tower-like structures, from a loading position at the base of the structure to a working platform which is raised as building proceeds. The device includes portions giving horizontal and vertical movement of a container, and includes a first transport unit at the loading level, a vertical hoist, and a second transport unit mounted on the working platform. The second transport unit includes a radial track movable around the working platform to deliver materials from the hoist, which is centrally situated, to different working areas around the structure. A special feature of the device is the use of a carrier frame which is square in plan view and which is supported on two hoist ropes attached to opposite corners of the frame, and which is also guided by guide tubes connected to the remaining two corners of the frame and which are located by downwards travelling reaches of the hoisting rope.

Abstract: The cable drum for the hoist cable of a hoisting device is driven by a hydraulic motor with a constant displacement that in its turn obtains drive fluid from a pump with a variable displacement. The displacement of the pump, and with that the speed and rotational direction of the cable drum, is operated by means of the rod of a piston in a double acting hydraulic cylinder, the piston being displaceable in the cylinder by means of pressure fluid, which pressure and direction of flow is adjustable by means of valves, which in their turn are operated electrically from a control lever.