Abstract: A system for pulling posts is disclosed. The system for pulling posts comprises a mast extending along a direction having a vertical component, an elongated arm rotatably and pivotably supported by the mast and extending at an angle relative to the mast, a pusher with first and second opposite ends, the first end of the pusher being configured to support the elongated arm at a first location of the elongated arm, and the second end of the pusher being configured to contact a ground surface, the pusher being configured to increase in length to drive the first location of the elongated arm away from a ground surface and thereby change the angle relative to the mast, and a pole attachment site at a second location of the elongated arm.

Abstract: The present invention relates to a telescopic device of single-cylinder latch type and a crane. The telescopic device of single-cylinder latch type is applied to a telescopic boom system and includes: a telescopic cylinder, for driving telescopic boom sections of the telescopic boom system to execute a telescopic action relative to a basic boom section; double boom pin structures, arranged on both sides of the tails of the telescopic boom sections to lock and unlock the telescopic boom sections; an boom pin pulling and plugging mechanism, arranged on the cylinder barrel of the telescopic cylinder to execute pulling and plugging operations on the double boom pin structures; and a cylinder pin structure and a cylinder pin cylinder, both arranged on the cylinder barrel of the telescopic cylinder and to lock and unlock the cylinder barrel of the telescopic cylinder and the telescopic boom sections.

Abstract: A caregiver's helper lift utilizes a unique hoisting apparatus, a lifting harness worn by a patient, and a control apparatus to allow a caregiver to raise and lower a patient into/out-of a wheelchair and into/out-of a vehicle, down to or up off a floor, or to any other position/location that a patient needs to be moved. The lifting harness can clip to a lift attachment which is affixed to a helper lift suspension cable/rope/etc. The caregiver's helper lift utilizes a crane arm to suspend the patient and allow him or her to be repositioned by simply rolling/turning the lift. By actuating the hoisting apparatus control system, the patient can be controllably raised and lowered as desired. The crane arm can be adjustably attached to a power T upright which is itself attached to a brace base. At least two beam extensions extend laterally from the brace and provide stability.

Abstract: The invention provides a davit with a number of useful features. A jib of the davit can be made with an overload indicator, which provides a straightforward, visible mechanism to ascertain whether the davit is fit for use following an overload condition. The jib can be made collapsible with telescoping sections, at least one of the sections having a plurality of flats to allow easy connection with other components of the davit, such as the lifting head. A single bearing can be used to rotatably couple the davit to the shaft, or king post, with a plurality of different-spaced bores to account for different diameters of shaft. Either or both of these improvements allow the davit to be manufactured easily and erected easily by users.

Abstract: A servicing system (30 or 300) for servicing a brake device (24) of a brake system comprising the brake device (24) and a brake disc (22) is described. The servicing system (30 or 300) includes a frame (32 or 302), and the servicing system (30 or 300) is further configured for mounting the frame (32 or 302) in a fixed position relative to the brake disc (22), supporting the brake device (24) to allow the brake device (24) to be moved on the frame (32 or 302) relative to the brake disc (22) and lifting the brake device (24) to allow the brake device (24) to be raised or lowered relative to the brake disc (22).

Abstract: A caregiver's helper lift utilizes a unique hoisting apparatus, a lifting harness worn by a patient, and a control apparatus to allow a caregiver to raise and lower a patient into/out-of a wheelchair and into/out-of a vehicle, down to or up off a floor, or to any other position/location that a patient needs to be moved. The lifting harness can clip to a lift attachment which is affixed to a helper lift suspension cable/rope/etc. The caregiver's helper lift utilizes a crane arm to suspend the patient and allow him or her to be repositioned by simply rolling/turning the lift. By actuating the hoisting apparatus control system, the patient can be controllably raised and lowered as desired. The crane arm can be adjustably attached to a power T upright which is itself attached to an H brace base. At least two beam extensions extend laterally from the H brace and provide stability.

Abstract: In one aspect of the disclosure, a cylinder-driven lifting mechanism of a compaction machine includes a cylinder having a first end and a second end, a fixed pulley set, a movable pulley set, a rope having a head end, and a tail end configured to connect a compaction hammer. The first end of the cylinder is connected to a vehicle body of the compaction machine and the second end of the cylinder is connected to the movable pulley set. The rope is wound on the fixed pulley set and the movable pulley set and is then connected to the compaction hammer. When the cylinder performs extension and refraction movement, the movable pulley set moves with the cylinder, the distance between the movable pulley set and the fixed pulley set increases or decreases, and the compaction hammer connected to the tail end of the rope is lifted up or dropped respectively.

Abstract: A telescopic boom provided in a crane includes a boom body and a telescopic cylinder for extending/contracting the boom body. A roller is provided in a tip end portion of the telescopic cylinder to be rotatable in a longitudinal direction. A peripheral surface of the roller is formed to be curved (crowning) in a convex shape outside as viewed in the longitudinal direction and make contact with a lower plate of the boom body in a state where both corner parts are away from the lower plate.

Abstract: A boom truck includes a telescopic lifting boom with a lifting unit and a support structure having a first support arranged on the chassis of the boom truck. A second support in the form of an elongated bearing and support beam body extends in the longitudinal direction of the boom truck. The beam body is pivotally mounted to the first support about a rear bearing axis, whereas the lifting boom is pivotally mounted to beam body about a front bearing axis. Actuators act on the beam body and the lifting boom as a unit and act to pivot the lifting boom about the front bearing axis.

Abstract: A telescopic boom broadly comprises an elongated hollow outer boom, an elongated inner boom telescopically received within the outer boom, and a guidance structure for guiding the inner boom for telescopic movement is provided. The guidance structure includes a plurality of guide rails attached to the interior corners of the outer boom, a first roller assembly attached to one end of the inner boom, a second roller assembly attached to one end of the outer boom, and a mid roller assembly positioned proximal to the second roller assembly. The first roller assembly includes a plurality of wheels mounted on axles for engaging the guide rails. The second roller assembly includes roller bars positioned on opposed sides of one end of the outer boom for guiding the inner boom during telescopic movement. The mid roller assembly includes a third roller bar that engages guide rails positioned on the inner boom.

Abstract: A telescopic mast system includes a telescopic mast comprising a plurality of telescopic mast sections and a drive mechanism for extending and retracting the telescopic mast sections. The drive mechanism includes a rigid chain having one end connected to a last one of the telescopic mast sections to move the telescopic mast sections and a plurality of guide plates cooperating with the telescopic mast sections to prevent buckling of the rigid chain.

Abstract: A telescopic boom broadly comprises an elongated hollow outer boom, an elongated inner boom telescopically received within the outer boom, and a guidance structure for guiding the inner boom for telescopic movement is provided. The guidance structure includes a plurality of guide rails attached to the interior corners of the outer boom, a first roller assembly attached to one end of the inner boom, a second roller assembly attached to one end of the outer boom, and a mid roller assembly positioned proximal to the second roller assembly. The first roller assembly includes a plurality of wheels mounted on axles for engaging the guide rails. The second roller assembly includes a pair of roller bars positioned on opposed sides of one end of the outer boom for guiding the inner boom during telescopic movement. The mid roller assembly includes a third roller bar that engages guide rails positioned on the inner boom.

Abstract: A crane having a telescoping boom whose sections, are arranged in a base boom that can telescope individually, in and out, after disengaging locking pin connections that are secured in the respective moved out or moved in positions by locking pins. A guide profile head is arranged at an end remote of the articulation of the safety locking unit to the inner end of the base boom. To lengthen the boom without substantially changing the telescopic system itself, the guide profile head is detachably fastened to the safety locking unit. An additional guide frame, whose length is dimensioned corresponding to the length of the telescoping boom that has been expanded by additional sections inserted in the telescoping boom, is mounted in place of the guide profile head, and that a guide profile head can be arranged at the free end of the guide frame.

Abstract: A boom truck, enabling handling of freight containers both above as well as below ground level, is disclosed having a telescopic lifting boom with a lifting unit for carrying the container and a support structure having a first support arranged on the chassis of the boom truck at the rear portion thereof. According to the invention, the support structure further has a second support in the form of an elongated bearing and support beam body for the lifting boom, which extends in the longitudinal direction of the boom truck and has a rear end located close to the rear end of the chassis and a front end located close to the front end of the chassis, and which is further pivotally mounted to the first support about a rear bearing axis located close to the rear end of the beam body, whereas the lifting boom is pivotally mounted to the beam body about a front bearing axis located close to the front end of the beam body and close to the front end of the base portion of the lifting boom.

Abstract: A mast section for a telescoping tower system is made by aligning press brake tools along the length of the metal sheet at spaced width locations and forming the corners of the tube. After forming of the last corner, an opening remains along the length of the tube. The press brake male tool axis is offset sufficiently to permit the tool to apply forming force to the last corner of the tube through the opening, and is sized to remove the tool from the opening. At least three mast sections are nested to form the tower system. Pulleys for a cable extension system are mounted near the upper and lower ends of a wall of an intermediate mast section, with one of the pulleys being oriented at an acute angle to the mast section wall to permit routing of the cable.

Abstract: A jib crane is provided which can prevent an unexpected movement of a burden and can sufficiently ensure the safety of a burden handling work. The jib crane has hoisting wire ropes 22 for lifting up and down of a hook 34, derricking wire ropes 24 for derricking operation of a jib 14 and a conversion device 38 for fixing tips of the wire ropes 22 and 24 to a revolving frame 58 of a revolving table. The conversion device 38 has a V-shaped link 62 pivotally supported on a bearing bracket 56 via a pivot pin 60. The tips of the wire ropes 22 and 24 are connected to paired link arms 62a and 62b of the link 62.

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 the rotating bed; a load hoist line trained over a pulley on the boom and wound on a load hoist drum connected to the rotating bed; and a boom hoist drum mounted in a frame. The boom hoist drum frame is connected to the rotating bed and a boom hoist line is wound on the boom hoist drum and connected to an upper equalizer and a lower equalizer, with the upper equalizer connected to the top of the boom by fixed length pendants, such that rotation of the boom hoist drum changes the amount of boom hoist line between the lower equalizer and the upper equalizer, thereby changing the angle between the rotating bed and the boom.

Abstract: A tensioning system for a mobile telescopic crane having a telescopic mast includes at least one tensioning cable for bracing the telescopic mast and at least one tensioning winch mounted on the crane superstructure for tensioning the cable. The tension in the cable creates a pressure bias within the mast. The winch is movable with respect to said superstructure of the crane and movement of the winch relative to the superstructure also imposes tension on the tensioning cable.

Abstract: The invention relates to a tensioning system for a mobile telescopic crane, in which the telescopic mast is outwardly braced via a tensioning means, and wherein said tensioning means is guided along or over the telescopic mast and fastened to the telescopic mast in such a way that a pressure bias of the mast is created in the area of the tensioning means guide. The tensile units or winches of a system in accordance with the invention are arranged on the crane superstructure at a distance from the level luffing plane of the telescopic mast of the crane, such that the tensioning means can absorb a substantial proportion of the loads having components perpendicular to the level luffing plane. The tensioning means tensile units or winches of a system in accordance with the invention are arranged on the crane superstructure, such that they can shift.

Abstract: A mobile cellular telephone tower comprises a self-propelled base and a tower connected to the base. The tower includes a base segment and at least a first extendable segment operatively connected to a second extendable segment. A winch is connected to the base, and a first cable is connected between the base segment and the first extendable segment to extend the first extendable segment. A second cable is connected between the winch and the second extendable segment to retract the second extendable segment. Cellular telephone network testing equipment mounted on the tower.

Abstract: In a self-traveling working machine such as a crane, a working attachment such as a boom is arranged to transversely extend below an operator's cabin in such a manner that part of the cabin overlaps the attachment, it being arranged that during crane operation, the cabin is moved widthwise outside the working machine to avoid interference with the boom.

Abstract: Transfer machine, intended for transferring loads (K), especially containers, wherein the transfer machine comprises a frame (R) equipped with a wheelwork (P); a horizontal support plane (1) located in connection with the frame (R) for supporting the load (K) during the transfer, and a vertical transfer apparatus (S) for lifting the load (K) on the support of the support plane (1) and off the support of the support plane (1), wherein the vertical transfer apparatus (S) is arranged to lift and lower loads (K) from the side of the transfer machine and thereby from the side of the support plane (1). The vertical transfer apparatus (S) of the transfer machine is placed in connection with the frame (R) on the first side of the support plane (1), and the vertical transfer apparatus (S) is arranged to reach over the support plane when lifting or lowering the load (K), in order to move the load (K) onto the support plane (1) or off the support plane (1) from the second side of the support plane (1).

Abstract: A boom truck is provided which has optimum operating and transport positions. In the operating position an operator's cab is mounted substantially centrally of the chassis of the boom truck, with the boom above the cab and pivotally mounted to the rear of the cab (over the rear axle) for rotation about a first horizontal axis to provide a lifting force when the boom is pivoted by a hydraulic cylinder or similar linear actuators. In transforming the boom truck to an ease of transport position, the cab is slid on rails to one side of the chassis (preferably in the direction substantially parallel to the axles of the chassis), the support for mounting the pivot for the boom is itself pivoted about a second substantially horizontal axis so that the boom lowers, and ultimately the boom moves to a position next to the cab, with at least part of the boom, and perhaps substantially all of the boom, below the top of the cab.

Abstract: An improved lift mechanism that is portable and towable, and has a telescopic and angularly adjustable load carrying boom, four telescopic support legs with pivotable wheels thereon, and a low center of gravity frame of a two part construction pivotally connected together and having a tilt indicator warning thereon.

Abstract: The invention provides a drive system for extending or retracting a boom. The boom comprises an elongated boom slidably mounted to a vehicle. The drive system comprises: a flat belt extending generally parallel to the boom; a rotatable drum mounted to the vehicle; and a pair of spaced apart rollers adjacent the rotatable drum. The belt is attached to the boom by couplings at either end of the belt. A loop of the belt extends through a gap between the pair of spaced apart rollers and around an outer circumference of the rotatable drum. The gap has a width less than a diameter of the rotatable drum. The drive system can be used to advantage in a forestry machine such as a tree delimber.

Abstract: A portable lifting apparatus for lifting and transferring of patients for use in combination with a sling or the like support. Separate motors are provided for control of up and down movement of the lifting arm, clockwise and counter-clockwise rotation of the column, extension and retraction of each of the legs individually and divergence and convergence of both legs simultaneously.

Abstract: A boom truck is provided which has optimum operating and transport positions. In the operating position an operator's cab is mounted substantially centrally of the chassis of the boom truck, with the boom above the cab and pivotally mounted to the rear of the cab (over the rear axle) for rotation about a first horizontal axis to provide a lifting force when the boom is pivoted by a hydraulic cylinder or similar linear actuators. In transforming the boom truck to an ease of transport position, the cab is slid on rails to one side of the chassis (preferably in the direction substantially parallel to the axles of the chassis), the support for mounting the pivot for the boom is itself pivoted about a second substantially horizontal axis so that the boom lowers, and ultimately the boom moves to a position next to the cab, with at least part of the boom, and perhaps substantially all of the boom, below the top of the cab.

Abstract: A telescopic rod composed of a plurality of tubular rod sections which are mounted so as to be slidable within each other includes a multistage piston-cylinder unit which is arranged within the telescopic rod and is connected to the outermost rod section of the telescopic rod and to the last inner rod section of the telescopic rod. Locking bars are provided in the areas of the inner end faces of individual sections, wherein the locking bars are displaceable in a direction transversely of the longitudinal direction of the rod sections and wherein the locking bars can be placed in operative engagement with the respectively adjacent outer rod section. When the rod sections of the telescopic rod are in the extended end position, the locking bar of each inner rod section engages in a positively locking manner in an opening of the respectively outer adjacent rod section. Spring-biased clamps are provided on the outer sides of the rod sections located between the outermost rod section and the innermost rod section.

Abstract: A telescopic boom including an elongated hollow outer boom, an elongated inner boom telescopically received within the outer boom, and guidance structure for guiding the inner boom for telescopic movement is provided. The guidance structure includes a plurality of guide rails attached to the interior corners of the outer boom, a first roller assembly attached to one end of the inner boom, and a second roller assembly attached to one end of the outer boom. The first roller assembly includes a plurality of wheels mounted on axles for engaging the guide rails. Each of the wheels includes an arcuate rail-engaging portion which presents a radius of curvature equal to the radius of curvature of the guide rails. The second roller assembly includes a pair of roller bars positioned on opposed sides of one end of the outer boom for guiding the inner boom during telescopic movement. Each of the roller bars extends transverse to the longitudinal axis of the outer boom and is rotatably mounted on an elongated shaft.

Abstract: A material handling vehicle comprising a top, bottom, two sides, and two ends, the vehicle having a central axis of extension extending from end to end thereof, the vehicle having a frame disposed therewith the frame having disposed proximate the bottom thereof at least a first and second axle upon which are disposed wheels for engaging terrain being traversed, the bottom of the axles defining a first plane, the frame being disposed above the first plane, the frame having disposed proximate one side thereof and to one side of the central axis of the vehicle a cab wherein an operator having a line of sight is located in use, the frame having disposed on the other side thereof and on the opposite side of the central axis of the vehicle whereat the cab is disposed, driving structure, the driving structure having a bottom, the bottom of the driving structure being disposed on top of the frame and being disposed in a plane above the first plane of the vehicle, and the top of the driving structure being disposed be

Abstract: A portable hoist adapted for attachment to a ball hitch mounted in a central location in a flat bed of a truck is disclosed. The hoist comprises an elongate base frame member, a receptacle mounted at the front end of the base frame member and adapted for releasable attachment to the ball hitch, an upright frame member, and a boom having load engaging device mounted to the upright member. The upright member and the base frame member are pivotally interconnecting so as to permit pivotal movement of the upright frame member about a horizontal axis extending laterally across the bed of the truck. A load is lifting via the operation of lifting device interconnected between the base frame member and one of the upright frame member and the boom.

Abstract: A mobile vehicular apparatus for moving an operator around a three-dimensional aerial work location such as an electric cable or wire supported on posts includes a mobile vehicle having a vehicle body, a boom upwardly extensibly and downwardly collapsibly mounted on the vehicle body, an operator's cabin mounted on a distal end of the boom, cabin having a vertical recess defined in a rear side thereof, at least one manipulator operatively connected to a front side of the cabin, and a lifter operatively connected to the rear side of the cabin. The lifter is collapsibly storable in the recess and extensible from the recess with a distal end portion of the lifter being positioned in overhanging relation to the cabin, the lifter supporting a winding device on the distal end portion.

Abstract: There is disclosed a mobile crane having at least one hollow load bearing support member which is rotatable about a base. The load bearing support member is pivotally connected to a hollow boom which telescopically receives a plurality of secondary hollow and interengageable booms. The load bearing support member and boom are pivotally connected by an inwardly collapsible support. The crane cable is connected to a drive source and extends within the hollow booms and load bearing support member and is releasably retained by at least one boom. The crane may be automatically unfolded from a storage position when the boom is substantially parallel to the mast, to an operational position when the boom is angularly inclined to the load bearing support member.

Abstract: A mobile vehicular apparatus for moving an operator around a three-dimensional aerial work location such as an electric cable or wire supported on posts includes a mobile vehicle having a vehicle body, a boom upwardly extensibly and downwardly collapsibly mounted on the vehicle body, an operator's cabin mounted on a distal end of the boom, the cabin having a vertical recess defined in a rear side thereof, at least one manipulator operatively connected to a front side of the cabin, and a lifter operatively connected to the rear side of the cabin. The lifter is collapsibly storable in the recess and extensible from the recess with a distal end portion of the lifter being positioned in overhanging relation to the cabin, the lifter supporting a winding device on the distal end portion.

Abstract: The possibility of the end 26 of a boom 20 of a vehicle mounted crane being moved downwardly into engagement with part of the crane or the vehicle on which it is mounted and causing damage thereto during elevation of a mast 18 for the crane from a stowed position (FIG. 2) to an elevated position (FIG. 1) is avoided in a construction wherein the mast 18 is formed of a parallelogram linkage including rigid links 60 and cylinders 72 which assure that the attitude of the boom 20 relative to a base 10 for the crane will not change during elevation of the mast 18.

Abstract: In a multiple stage boom including a base boom and a plurality of relatively extensible and retractable boom stages, a system for displaying the load rating information relative to the boom includes an angle measuring assembly and a color coded boom and chart assembly. A plurality of separate markings are provided on and spaced from one another along the length of an intermediate boom stage of the boom in such a way as to be sequentially revealed when the boom stages are extended from a retracted position. Each of the markings are representative of the length of the boom at the point of extension of the boom where the marking is first revealed on the boom. A plurality of color sections extend along the intermediate boom stage, each of which is provided between a different pair of the markings and is colored differently than the other color sections to provide visible confirmation of the distance of extension of the boom.

Abstract: A telescopic boom mobile crane wherein the boom may be disconnected from the turntable characterized in that the crane vehicle has rollers (or their equivalent) to support the collapsed boom on the vehicle while permitting the boom longitudinally to move along the vehicle, releasable means being provided pivotally to connect the base of the boom to the vehicle and drive means being provided to move the boom longitudinally relative to the vehicle. This enables a boom of longer length that hitherto to be stowable on the crane vehicle itself for transportation.

Abstract: A wheel crane wherein the maximum radius of pivotal motion of a boom is minimized and the boom foot mounting point can be positioned as rearwards as possible to realize an increase of the boom length. The wheel crane comprises a lower running body, an upper pivotal body, a boom mounted for up and down pivotal motion around a boom foot pin on the upper pivotal body, at least two winch drums and guide sheaves disposed at rear locations of the pivotal body. The boom foot pin is mounted at an end portion of the base end portion of the boom on the rear face side of the boom and at a location of the upper pivotal body rearwardly of the center of a rear axle of the lower running body.

Abstract: A multi-stage boom having a plurality of boom members including a first boom member, at least one intermediate boom member and a last boom member, each being slideably inserted into its subordinate boom member to undergo telescopic expansion and contraction. An operating shaft is connected pivotably at its bottom portion erectly to a peripheral lower end portion of the last boom member, and a plurality of adjusting shafts are each disposed pivotably at its bottom portion erectly to a peripheral upper end portion of each boom member except the first boom member. A first tension cable is connected at its one end to a lower end portion of the first boom member, lead therefrom through an upper end opening of a subordinate boom member, turned forwardly at a top portion of an adjusting shaft disposed at a peripheral upper end portion of the subordinate boom member, and connected at its other end to an upper end portion of the first boom member.

Abstract: A variable reach rough terrain load lifting apparatus comprising a vehicle having a frame; a boom having innermost, intermediate and outermost telescoping boom segments; and means for pivotally connecting the outermost boom segment to the vehicle frame and capable of reciprocal longitudinal movement therewith. The outermost boom segment has first and second hydraulic cylinders mounted therein for extending and retracting the intermediate and innermost boom segments, respectively. The pivotal connection means facilitates pivotal movement of the boom with respect to the vehicle while preventing buildup of corrosion products which would interfere therewith and further to facilitate repair or replacement thereof due to normal operation. The innermost boom includes end effector means attached to the forward end thereof by means for quick connection and disconnection.

Abstract: A crawler crane made up of a crane frame and body on tracks, a telescoping boom projecting from the body, a fixed-length A-frame boom with rotatable arms, a mechanism for lifting the telescoping boom and a device for extending the telescoping boom.

Abstract: A telescopic mast system has a base tube, a plurality of axially movable coaxial inner tubes nestable successively within each other and within the base tube, and a winch supported at the lower end of the base tube with a pair of preferably wire ropes driven thereby for extending and retracting the inner tubes. The base and inner tubes have collars at their respective ends, the collars of adjacent tubes engaging each other to limit extension thereof and to provide additional structural support during application of bending loads on the mast system. The ropes are connected to pulleys mounted near or within tube collars so that the ropes and pulleys are totally enclosed within the mast system. As the winch is rotated in one direction, the ropes axially move the inner tubes from a nested or stowed position within the base tube to a fully vertically extended operational position.

Abstract: A portable, backpackable crane lift involving a retractable boom, boom cable, winch and winch cable mounted to a wheeled frame with extendable axles all which fold into a compact unit. A shoulder harness apparatus which attaches to the folded unit for carrying converts to a ballast carrying extension of the frame during operation. Such a lift is readily carried up a ladder for use on flat roofs to raise and place air conditioning heat exchangers and the like.

Abstract: Tensiometer placed on the free end of an aerially articulable boom such that the tensiometer's load indicator is visible from the bucket. A cable extending from the boom's free end may be attached to a working object such as a transformer. When the boom is raised, the working object is lifted off the ground. The tension placed on the cable causes a readout on the tensiometer indicating the load on the cable. Thus, a worker in the bucket can immediately determine whether the load on the cable exceeds the allowable limits.

Abstract: A tractor crane includes a boom having a root end adapted for pivotal mounting on a tractor, a load end which is adjustable in position relative to the root end, strut connector intermediate its ends, and load attachment device at or near the load end of the boom for attaching a load thereto. The crane further includes a strut having an upper end pivotally connected via the strut connector to the boom about an axis transverse to the boom and parallel to the pivotal axis at the root end. The strut also has a lower end with a mounting device for connection of the lifting arms of the three-point hitch of the tractor.

Abstract: A power actuator on the base section of a multisection telescoping crane boom can bridge at least one intermediate boom section to operate a biased locking pin retract mechanism employed in a system for remotely controlling the operation of a manual fly section of the telescoping boom. To enable the crane operator to know with certainty that the biased locking pin is in a fully engaged position, a visual indicator on the boom readily viewable from the crane operator's cab is directly mechanically linked to the biased locking pin and moves to the indicating position only when the locking pin is fully engaged.

Abstract: A separate boom vehicle is provided for transporting a telescopic boom, which is adapted to be coupled to a revolving superstructure and to be detached from it for transporting. The boom vehicle is provided in its forward portion with a coupling structure for retaining a telescopically extensible part of the telescopic boom, and is provided in its rear portion with a lifting structure for supporting the boom. The lifting structure is so arranged that when it has been longitudinally aligned with the revolving superstructure, a coupling yoke, provided at the lower end of the telescopic boom, is adapted to be displaced by extending and retracting cylinders along tracks provided on the revolving superstructure to a position in which bearing eyes of the telescopic beam register with bearing bores of the revolving superstructure. The revolving superstructure is provided with a pivot pin for coupling the boom to the revolving superstructure.

Abstract: A method for stretching and folding an extension jib in a wheeled type crane including a telescopic boom, and a suspension-rod-supported compression column type extension jib to be supported in a flat posture at the fore end of the boom in stretched state through right and left jib foot portions rotatably engaged with horizontal boom point pins extending transversely of the boom at the fore end thereof, the method including the steps of (a) providing on opposite sides of the extension jib right and left jib foot portions disengageably engageable with the boom point pins, one of the jib foot portions being rotatable relative to the boom about an axis extending in the axial direction of the jib; (b) stretching the jib from a folded position in which the top and bottom sides of the jib are disposed in an upright posture along one side of the boom, by engaging the one jib foot portion with the boom point pin on the folding side and turning the boom into an inclined position from a horizontal position, rotating th

Abstract: An attachment jib for supporting various working devices, such as a pipe manipulator, includes a support base which can be rigidly coupled removably with existing elements on the nose block of a telescopic crane boom. The jib includes telescopic sections and its base section is pivotally mounted on the support base and is luffed by power cylinders on such base through a wide angle. The jib contains another power cylinder to control extension and retraction of its fly section carrying the working device. An optional work support platform pivotally connected to the support base may be used either with or without the jib.

Abstract: A power actuator on the base section of a multi-section telescoping crane boom can bridge at least one intermediate boom section to operate a biased locking pin retract mechanism employed in a system for remotely controlling the operation of a manual fly section of the telescoping boom. To enable the crane operator to know with certainty that the biased locking pin is in a fully engaged position, a visual indicator on the boom readily viewable from the crane operator's cab is directly mechanically linked to the biased locking pin and moves to the indicating position only when the locking pin is fully engaged.