Abstract: The present invention relates to a crane (1) comprising a mast (2), an elongated boom (3) connected to the mast having a front portion (6) extending on one side of the mast and a rear portion (8) extending on the opposite side of the mast, and the boom (3) is linearly movable relative to the mast such that the length of the front portion and the length of the rear portion is adjustable by moving the boom relative to mast, and a counterweight (12) movably connected to the boom (3). The boom (3) and the counterweight (12) are arranged so that they can be moved independent of each other, and the counterweight and the boom are arranged so that the counterweight can pass the mast and be moved between the front portion (6) and the rear portion (8) independent of the position of the boom (3) with respect to the mast (2).

Abstract: A crane includes a crane body, a boom, a hoisting winch, and a rope holding device pressing a rope wound around a drum of the hoisting winch against the drum. The rope holding device includes an oscillating arm whose proximal end is attached to a base of the hoisting winch using a support shaft and distal end oscillates in a direction close to or away from the drum, and a rope presser which is attached to a distal end of the oscillating arm, extends in an axial direction of the drum between a pair of flanges, and abuts against the rope wound around the drum. A weight member, which biases a distal end side of the oscillating arm in a direction close to the drum by the gravity with the support shaft as a fulcrum, is provided at the proximal end of the oscillating arm.

Abstract: The invention relates to a method of monitoring the safety of a crane, in particular of a revolving tower crane having a revolving deck, wherein the crane has a sensor system and a crane control, and wherein furthermore at least one tilt sensor is provided. In accordance with the invention, the at least one tilt sensor is attached to the revolving deck of the revolving tower crane, with the monitoring of the crane safety taking place at least during the putting up and/or taking down of the revolving tower crane.

Abstract: A mobile crane including a frame which, in its upper part, is provided with a main support structure and which, in its lower part and on opposite sides of the lower part of the frame, is provided with lower beam structures transverse to the main support structure, and upright legs between the main support structure and the lower beam structures; at least one wheel or wheel arrangement at both ends of the lower beam structures, i.e. in each lower corner of the crane; a trolley arranged to move along the main support structure and provided with a hoisting member; at least one hoisting mechanism; at least one rope drum arranged to be run by the hoisting mechanism; and at least one rope arranged from the rope drum of the hoisting mechanism to the hoisting member for running it, the rope drum being further provided with at least one hoisting rope connected to at least one counterweight.

Abstract: Disclosed is a crane comprising: a lower body; an upper slewing body; a counterweight unit including a plurality of wheels to travel on the ground in a turning direction equal to a slewing direction of the upper slewing body while being suspended from the upper slewing body; a steering actuator for rotating each of the wheels around a steering-rotation center axis to change the steering angle; and a steering control device for controlling the steering actuator. The steering control device includes: a slewing-identification-signal receiving section which receives a slewing identification signal for identification of the slewing direction of the upper slewing body; and an actuator operating section operates the steering actuator to orient each of the wheels to the inside of a tangent line to an orbit of the wheel at the steering-rotation center axis, based on the identified slewing direction identified from the slewing identification signal.

Abstract: The present disclosure relates to a crane with a travelling undercarriage, an uppercarriage rotatably mounted on the same with a luffing boom and derrick boom arranged on the same, and a ballast carriage connectable with the uppercarriage via a coupling element, wherein the ballast carriage is a standardized heavy-duty transport device with separate drive and separate drive controller, and wherein this drive controller can be influenced as a result of the movement of the crane.

Abstract: A movable counterweight system moves under a material-handling vehicle to provide a safe low center of gravity, and avoid interference to the operator.

Abstract: The present invention discloses a mobile counterweight equipment of crawler crane, which includes a main platform, wherein the said mobile counterweight equipment further includes a pair of sliding rails on two sides of the main platform, slider means and counterweight equipment on the said sliding rails; the said counterweight equipment is connected to the said slider means, the said slider means slides back and forth on the said sliding rails. The beneficial effects of the present invention are: the total weight of the counterweight is greatly reduced, the structure is simplified and it is easy to operate and to maintain.

Abstract: A lift crane includes a carbody; moveable ground engaging members mounted on the carbody allowing the crane to move over the ground; a rotating bed rotatably connected to the carbody about an axis of rotation; a boom pivotally mounted about a boom hinge point on the front portion of the rotating bed and including a hoist line for handling a load; a counterweight support beam coupled to the rotating bed; and a moveable counterweight unit comprising a counterweight tray suspended beneath the counterweight support beam wherein the counterweight tray is operable to move toward and away from the boom during a pick, move, and set operation by moving relative to the counterweight support beam. The crane has at least two set-up configurations: in a first set-up configuration the crane comprises a live mast, and in a second set-up configuration the crane comprises a lattice mast.

Abstract: A large mobile crane includes a revolving superstructure, a main boom hinged to the superstructure, and a derrick boom hinged to the superstructure. A modular counterweight system includes a traveling counterweight and a non-traveling counterweight connected to a crossbeam suspended from the distal end of the derrick boom so that the non-traveling counterweight is activated before the traveling counterweight.

Abstract: A portable anchorage assembly comprises an extension member interconnecting a counterweight assembly and a base. The counterweight assembly has a cavity configured and arranged to receive at least one weight. The extension member has a first end and a second end. The first end is pivotally connected to the counterweight assembly. The base is connected to the second end of the extension member and includes a wheel and at least one anchorage point. The base is pivotable about the counterweight assembly on the wheel to position the at least one anchorage point in a desired location.

Abstract: A variable counterweight system includes a counterweight and at least one linear transfer device. The counterweight preferably includes a plurality of individual counterweight members. Each linear transfer device preferably includes a moving track and a drive device. The moving track could be a chain or a belt. The drive device is preferably a hydraulic, electric or pneumatic motor. The moving track is preferably retained in a guide track. A control unit receives input from at least one vertical sensor. If an attachment or a boom is in an elevated position, then the control unit powers the at least one drive device to move the counterweight to a rear of the skid steer. If the attachment or boom is in a lowered position, then the control unit powers the at least one drive device to move the counterweight to a front of the skid steer.

Abstract: A camera crane includes an improved balancing system having a weight bar attached to the crane arm, and balance weights moveable along the weight bar. Substantially each balance weight can have upper rollers resting on the upper surface of the weight bar, to support the balance weight on the weight bar and allowing the balance weight to roll along the weight bar. A brake may be provided on the balance weights to lock the balance weight into a selected position on the weight bar. If used, the brake may have a moveable brake pad and a brake stop. The weight bar can be attached to the crane arm via mounting bars, and with the balance weights each including a slot to allow the balance weight to move over or past the mounting bars.

Abstract: The present invention relates to a lattice mast crane having a traveling gear, a swiveling crown arranged on the traveling gear and a revolving deck which is rotatable via the swiveling crown and on which a main boom and a derrick boom are arranged and having a ballast box, with the revolving deck being mounted on the swiveling crown via a spacer tube and with the guide frame forming the track of the derrick ballast projecting outwardly beyond the ballast box.

Abstract: A mobile lift crane includes a carbody having moveable ground engaging members; a rotating bed rotatably connected to the carbody such that the rotating bed can swing with respect to the ground engaging members; a boom pivotally mounted on a front portion of the rotating bed and a mast mounted at its first end on the rotating bed and having a second end; and at least one hydraulic cylinder pivotally connected at a first end to the rotating bed. The hydraulic cylinder is positioned and configured so as to be able to raise the second end of the mast from the mast being in a near horizontal position to a position where the mast is used during crane pick, move and set operations. In a preferred embodiment, at least one arm is pivotally connected at a first end to the rotating bed and at a second end to the hydraulic cylinder. The arm and cylinder are connected together such that extension and retraction of a piston within the hydraulic cylinder causes the second end of the arm to raise and lower.

Abstract: A machine for lifting and handling loads with an orientable articulated placing jib, comprising a mast with a rotating pivot, an articulated jib (16) comprising a jib foot (19), articulated at its first end on the top of the mast by a horizontal rotation axis (27), a jib head member (18) articulated for rotation by a horizontal articulation axis (32) at the second end of the jib foot, a jib holding assembly comprising at least one stanchion (7), a jib holding line (11) and a moving counterweight (100) connected to the jib by the said holding line. The counterweight is made to follow a guiding track (1) with a variable slope (?), integral with the rotating pivot, supporting the said counterweight, arranged opposite to the jib, and where the variations in slope (?) are chosen so that the counterweight exerts a set of variable forces on the said jib and on the structure of the said machine, helping to balance the machine during movements of deployment/retraction of the jib in articulated working mode.

Abstract: A telescoping camera crane has mechanical drive and camera platform leveling systems, allowing for water resistant or submerged operation. Telescoping sections of the crane arm are driven by a hydraulic system, for smooth and near silent extension and retraction movement. The telescoping sections of the crane arm have a slight upward curvature, to compensate for deflection the arm, thereby improving performance. Electronic and mechanical stopping systems allow the camera platform to be smoothly, accurately, and reliably positioned. Camera platform levelling and stabilizing systems keep the camera level.

Abstract: A telescoping camera crane has mechanical drive and camera platform leveling systems, allowing for water resistant or submerged operation. Telescoping sections of the crane arm are driven by a hydraulic system, for smooth and near silent extension and retraction movement. The telescoping sections of the crane arm have a slight upward curvature, to compensate for deflection the arm, thereby improving performance. Electronic and mechanical stopping systems allow the camera platform to be smoothly, accurately, and reliably positioned. Camera platform levelling and stabilizing systems keep the camera level.

Abstract: A telescoping camera crane has mechanical drive and camera platform leveling systems, allowing for water resistant or submerged operation. Telescoping sections of the crane arm are driven by a hydraulic system, for smooth and near silent extension and retraction movement. The telescoping sections of the crane arm have a slight upward curvature, to compensate for deflection the arm, thereby improving performance. Electronic and mechanical stopping systems allow the camera platform to be smoothly, accurately, and reliably positioned. Camera platform levelling and stabilizing systems keep the camera level.

Abstract: A telescoping camera crane has mechanical drive and camera platform leveling systems, allowing for water resistant or submerged operation. Telescoping sections of the crane arm are driven by a hydraulic system, for smooth and near silent extension and retraction movement. The telescoping sections of the crane arm have a slight upward curvature, to compensate for deflection the arm, thereby improving performance. A riser section on the arm increases the effective length or reach of the arm. The extender section may also be pivotably mounted on the arm, so that it can quickly be moved into upright, inverted, or side positions.

Abstract: The invention relates to a mobile harbor crane for normal and heavy load operation, having an undercarriage and a superstructure mounted thereon. A tower is fastened on the superstructure and a jib which pivotable about a horizontal axis is arranged on a front side of the tower. During a normal mode of operation, the jib is held pivotably on the superstructure by a luffing cylinder coupled to the jib and to the tower and the load lifted and lowered via a hoisting cable guided to the jib head and having a snatch block suspended on it. For a heavy load operating load, the mobile harbor crane further includes a heavy load lifting winch with a heavy load lifting cable which is guided over a deflecting roller fastened to the jib and further guided to a roller assembly of a heavy load snatch block arranged releasably on the jib head.

Abstract: A convertible crane with a movable sheave assembly which is operable in two distinct positions. In the first position, the sheave is adjacent the body of a crane to enable it to operate in relatively restricted space without interference from obstacles adjacent the rear end of the base. In the second position, the sheave extends away from the body of a crane where it may be attached to an auxiliary counterweight to enable a crane to lift larger loads. The movable sheave assembly enables a crane to be easily and rapidly converted between normal and enhanced lifting modes.

Abstract: A lifting device which includes a frame and an elongated boom having a lower end pivotally connected to the frame along a pivot axis. The lower end of the boom has a counterweight connected thereto offset from the pivot axis. The counterweight has a center of gravity which is movable with respect to the pivot axis of the boom. The counterweight can be freely pivotal, fixed, or partially fixed with respect to the boom. When linkage is provided between the counterweight and the boom, the counterweight can be rolled or tilted so as to move the counterweight center of gravity with respect to the pivot axis of the boom.

Abstract: A counterweight installation and removal apparatus for a truck-mounted crane includes a counterweight having a bottom surface, a plurality of rollers attached to either the bottom surface of the counterweight or to a crane carrier deck, and at least one inclined surface positioned on the other of the bottom surface of the counterweight or the crane carrier deck to engage the plurality of rollers when the counterweight is installed and removed.

Abstract: An improved derrick structure comprising a column for supporting the derrick structure, a bracket horizontally rotatably mounted on the column, a boom vertically pivoted on the bracket so that the boom is divided into a first boom portion and a second boom portion, a winch drivable to hoist a hook for engaging an article intended to be transported by the derrick structure, a first dolly drivable to move the hook along the first boom portion, a counterweight drivable to move along the second boom portion to effectively balance the loading of the article hoisted by the derrick structure, and a controlling device for activating an electrical control circuit to control the driving of the winch, the dolly and the counterweight.

Abstract: A pivotally-mounted reeved counterweight system for a counterbalance-type crane which includes a wheeled counterweight carriage supporting a counterweight. A yoke provides the coupling means pivotally connecting the carriage and the rearward end of the platform or deck also known as the counterweight arm. A sheave is mounted on the yoke. The rope, which manipulates the boom upwardly and downwardly, retractably and extensibly extends from a hoist drum on the platform upwardly and is reeved about a mast sheave and extends downwardly, rearwardly and upwardly between the yoke sheave and a plurality of platform sheaves and mast sheaves.

Abstract: A crane has a generally horizontally disposed main boom arm centrally pivotally mounted on a turret supported for rotation atop a central column. The main boom arm supports a load at one end and a counterweight at its other end. The main boom arm load support end has a depending vertical arm, linked in parallelogram fashion with the turret, and with a lower rotatable load carrying swing arm movable through a full 360.degree. arc without interference with the column and turret. The column may be mounted on a dolly. A rack and worm pinion arrangement are provided on either the main boom or the counterweight for adjusting the distance of the counterweight from the column and turret, thus to balance the crane in a vertical plane.

Abstract: Fork lift truck comprising a chassis, a front and a rear axle supported by the chassis and having wheels at their outer ends, a portal which is pivotally connected to the front of the chassis, a fork, on which a load can be placed, being movable along said portal, an engine which is provided on the chassis for driving wheels of the fork lift truck, said truck being intended for being transported under the loading floor of a vehicle intended for goods carriage. A counterweight is provided outside the wheelbase at the end of the chassis located opposite the portal, whilst the portal is pivotally connected to the chassis in such a manner that the portal can be folded down over the engine and the counterweight against the upper side of the chassis.

Abstract: A hydraulic circuit for a large crane furnished with a counterweight carriage detachably connectable to the swivel unit of the crane.

Abstract: The earth moving machine has a body having a ground engaging propulsion device and a base frame mounted on the ground engaging propulsion device. The base frame is movable relative to the ground engaging propulsion device about a first generally vertical axis. A boom extends outwardly of the body and is mounted on the base frame for movement about a second axis transverse relative to the first axis. The boom has a dipper arm mounted at an outer end thereof for movement about a third axis also transverse to the vertical axis. An excavating implement is mounted at an outer end of the dipper arm for movement about a fourth axis also transverse relative to the first vertical axis. A hydraulic ram is mounted between the dipper arm and the boom to effect movement of the dipper arm relative to the boom and hence to effect movement of the implement towards and away from the body.

Abstract: A hydraulic drive system for a counterweight dolly in a counterbalance type crane having a crane body provided with a lower travelling structure an upper swivelling structure and the counterweight dolly connected to the rear portion of the upper swivelling structure through a connecting member, characterized by including a swivelling hydraulic motor for swivelling the upper swivelling structure of the crane body; a swivelling control valve for controlling the pressure of hydraulic oil to be fed to the swivelling hydraulic motor; a hydraulic circuit for swivelling operation which controls the amount of operation of the swivelling control valve; a hydraulic motor for the counterweight dolly which drives each wheel of the dolly; a dolly control valve for controlling the pressure of hydraulic oil to be fed to the hydraulic motor for the counterweight dolly; and a control circuit for actuating the dolly control valve in accordance with an operational pressure of the hydraulic circuit for swivelling operation and t

Abstract: A hydraulic drive system for counterweight dolly in a counterbalance type crane, including dolly driving wheels supported vertically movably through wheel supporting hydraulic cylinders at the lower portion of the counterweight dolly which is connected to the rear portion of a crane body; a wheel driving hydraulic motor connected to each of the wheels; a support pressure detecting mechanism for detecting a support pressure for each wheel supporting hydraulic cylinder, the support pressure detecting mechanism being provided in a drive circuit for the cylinder; and a mechanism for controlling the driving pressure for the wheel driving hydraulic motor in accordance with a detected value provided from the detecting mechanism.

Abstract: A heavy duty crane which essentially includes in combination: a first mobile and swivellable base unit, a boom mounted on the first base unit, a second mobile and swivellable base unit, a counterweight mounted on the second base unit, a link frame interconnecting the two base units, and a gantry structure supported on and across the two base units, wherein the link frame includes a front frame having a fore end thereof connected to the first base unit and a rear frame having a rear end thereof detachably connected to the second base unit, the rear end of the front frame being detachably connectible to the fore end of the rear frame and to the second base unit.

Abstract: Disclosed is a crane wherein a trailer-like counterweight carrier has a horizontal motion transmitting connection with a platform which is swivelably mounted on a crane base and which supports the boom and the mast of the crane. Guy connections between the counterweight carrier and the top of the mast and between the mast and the boom translate forward tilting force that a lifted load imposes upon the boom into lifting force on the counterweight carrier. A lost motion connection between the counterweight carrier and the platform comprises rigid members. It allows the carrier to be lifted to a predetermined height above the ground and at that point imposes upon the crane chassis further lift force upon the counterweight carrier, so that the crane base cooperates with the counterweight in resisting forward tilting of the boom under heavy loads. The lost motion connection requires no adjustment to adapt it for different loads and different inclinations of the boom and mast.

Abstract: A windlock for selectively preventing relative pivotal movement between a mobile platform and a horizontal interconnecting stinger at the base of an elevated crane. The stinger is normally interconnected to one load platform for relative pivotal movement about the stinger central axis. Outer horizontal surfaces on the stinger structure are longitudinally movable relative to the platform to a position between adjustable screws which engage them to lock the stinger against rotational movement. This locking arrangement applies the heavy weight of a remote counterweight unit to assist in preventing lateral tipping of the load platform on which the elevated boom is supported. Outboard jacks on the platform further stabilize it against lateral tipping movements.

Abstract: A crane structure mounted on a transport vehicle, preferably a marine vessel, is disclosed. The crane structure includes a gantry structure mounted on a vertical tower structure and having boom portions protruding from the tower structure. Preferably, the boom portions may be pivotally lowered from their operating positions and the tower structure may be rotated in a horizontal plane, thereby reducing the overall dimensions of the crane structure to allow transport under overhead obstructions and through narrow passageways.

Abstract: An articulated power lifting machine has a tool at the end of its working arm. The position of the sections of the working arm is sensed and made to operate a tool levelling system. That same sensor is made to move counterweights in a system which achieves simplicity by treating the need for counterweighting as equal, except for reference point of movement, as equivalent to the need for levelling. The arrangement lends itself to use with a transporter which is constructed building block style.

Abstract: A hammerhead type of crane has a structural tower with opposed structural cantilevers extending horizontally therefrom and there is a horizontal track along which a load carrying trolley may move through the tower between limits near the outer ends of the cantilevers and a second horizontal track along which a counterweight may travel at the same speed and distance but in the opposite direction and with the load trolley and counterweight passing each other as they move through the tower from one cantilever to the other. The counterweight is moved by means of a cable that has its opposite ends attached to the counterweight and which between its ends is wound about a reversible drum arranged to selectively move the counterweight in one direction or the other.

Abstract: A counterbalanced crane structure having an upright boom and diverging staymast mounted to a ground supported mobile crane base. An independent mobile counterweight unit has a vertical counterweight strut connected to the outer end of the staymast. The counterweight unit is interconnected with the crane base by an elongated horizontal stinger assembly. The counterweight unit is powered to move in an arc, the center of which is determined by the crane base. Turning motion is transmitted from the moving counterweight unit to the main boom and staymast by the stinger. Movable connections on the stinger permit pivotal movement of the counterweight unit about an axis that is substantially radial with the center turning axis of the mainboom and staymast and another pivot axis that is transverse to the radial axis. Limited movement of the counterweight unit toward or away from the crane base is permitted to eliminate direct transfer of tension and compressive stresses through the stinger.

Abstract: A motor vehicle having excavating machinery mounted thereon and having at least two axles, at least one of which is driven, and further including an operator cab, the vehicle having counterweights on each lateral side of the cab, guides for the counterweights extending lengthwise of the vehicle on each lateral side of the cab, the counterweights being movable along the guides from a first position above one of the axles to a second position above the other of the axles, and apparatus for selectively securing the counterweights in each of the two positions.

Abstract: In a heavy-duty crane particularly suitable for lifting heavy loads over tall buildings, a substructure supports a rotatable main boom. A jib for carrying the load and a secondary spar for carrying a counterweight by means of a cable are hinged to the tip of the main boom. The counterweight swivels together with turning of the loaded crane. The jib is guyed by way of the secondary spar which overhangs so far that the counterweight is disposed beyond the confines of the substructure.

Abstract: A crane structure is mounted on a platform and has a tower assembly with spaced apart columns spanned at their upper extremities by an upper structure. A gantry includes a central section, fixedly secured on the upper structure, and first and second outer gantry sections. The outer sections are pivotally connected to the central section, and are movable between horizontal operating positions and generally vertical transport positions. The gantry sections have at least two vertically spaced series of tracks thereon. In the upper tracks a counterweight is mounted on casters or rollers, and a lift trolley is similarly disposed on the lower tracks. A sheave and winch assembly interconnects the counterweight and the lift trolley through a cable arrangement, whereby corresponding movements of the counterweight and the lift trolley are effected through operation of the winch. The lift trolley is adapted to travel substantially the full lengths of the gantry sections when the sections are in operating positions.