Abstract: The present invention relates to a suspension load and tipping moment calculating apparatus for a mobile crane which can calculate a suspension load and a tipping moment with high accuracy and use an excessive load prevention load while ensuring safety. For this reason, the apparatus is provided with sensors (50, 48, 46) for detecting a boom length, a boom angle, and an axle weight of a boom derricking cylinder (26) on a second boom (28) side, and is equipped with a controller (38) for calculating a suspension load (Wa) suspended from the second boom (28) based on signals from these sensors. In addition, for calculating a tipping moment, a boom length sensor (44) and a boom angle sensor (42) on a first boom (24) side are provided.

Abstract: A transportable multi-purpose crane includes a platform having outriggers disposed at opposite ends thereof. A turntable is rotatably mounted to the platform between the outriggers on opposite ends of the platform, and has a center axis of rotation. A riser boom, having a first end and a second end, is pivotally mounted to the turntable at its first end, and the second end supports a first load carrying device. The riser boom points in a first direction with respect to the center axis of rotation, and is a telescoping boom. An upper boom, having a first end and a second end, has its first end pivotally mounted to the second end of the riser boom. The second end of the upper boom supports a second load carrying device. The upper boom points in a second direction, opposite the first direction, with respect to the center axis of rotation, and is a telescoping boom.

Abstract: A crane boom top is disclosed in which a sheave assembly having a number of sheave sets is supported on the crane boom top by boom sheave supports. Each sheave set is mounted on an individual shaft and connectors connect the individual shafts to the boom sheave supports.

Abstract: A mobile crane includes an undercarriage or lower crane carrying chassis, an upper load lifting and carrying chassis pivotally mounted on the lower chassis, a cab located on the upper chassis for operating the crane, a base section that can be swivelled about a horizontal axis, and a separate boom attachable to a free or operating end of the base section. The base section has a novel, essentially one-piece construction that is designed in such a manner that with it alone especially crane operations can be performed. Attachment devices for attaching the separate boom are provided on the free end of the base section. The base section extends virtually over the entire length of the lower chassis. Thus, maximum loads and maximum lifts can be obtained with universal and versatile application.

Abstract: An in-vehicle device for lifting objects into and out of the storage areas of the vehicle in which it is installed. The device is attached to the inside wall, floor, or ceiling area of the vehicle in which it is installed. It is fixedly attached to the vehicle by a mounting element which is connected to a swivel base element containing, in one embodiment, a winch with a cable running through a telescoping arm protruding from the base. The arm telescopes into and out of the base. The cable has a hook on its end to enable it to hook onto handles or ropes on objects to be stored in the vehicle and removed therefrom to a desired location. The winch is operated manually or by an electric motor or other mechanical means. The mounting element is attached to the vehicle by bolts, rivets, adhesives and the like. The base can be connected to the mounting element by a ball and socket joint to enable it to swivel in all directions, or it can be connected by a joint which enables it to swivel horizontally only.

Abstract: A crane, particularly a track-bound mobile crane, having a luffing jib located on a vehicle frame so as to be slewable upward and downward around a horizontal axis and rotatable around a vertical axis. In order to transport long and heavy loads in narrow areas, especially during the construction of bridges or tracks, the luffing jib is supported on at least one swivel bearing located on a vehicle frame end and is slewable upward and downward or liftable by a lifting drive arranged between the ends of the vehicle frame.

Abstract: The invention relates to a mobile crane comprising a lower vehicle and an upper vehicle turningly mounted thereon and bearing a telescoping boom with a luffing cylinder for the pivoting thereof. The telescoping boom comprises two parts able to be bolted together and each having an external tube, from which respectively at least one telescope member may be extended.

Abstract: A truck mounted crane assembly includes a turntable lock, a boom rest which interacts with the piston and cylinder device, and a swing away hoist mount. The turntable lock includes a pin which is manually retractable upon rotation of a handle from a position preventing relative rotation between a turntable and a pedestal to a position allowing such relative rotation and which can be secured in the first and second positions. The boom rest is mounted on the boom and rests on the cylinder of the piston and cylinder device when the boom is lowered to a predetermined position, thus taking much of the pressure off the piston. The boom rest is movable from a position in which it is capable of supporting the boom to a position in which it is incapable of supporting the boom and in which the boom is thus lowerable below the predetermined position. The provision of the turntable lock and boom rest obviates the need for a cradle rest for the boom.

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 multistage telescopic boom or jib, in particular for a loading crane on a truck, has hydraulic units each including a piston and a cylinder arranged between the successive, telescopically nested arms. A pipe projects axially from the bottom of the cylinder into the chamber of the cylinder, sealingly extending into the hollow piston rod when the piston is retracted and sealing the chamber of the cylinder from an inner chamber of the hollow piston rod. In order to ensure an automatic extension sequence of the telescopic arms, the inner chamber of each hollow piston rod is linked to the cylinder chamber of the next outer hydraulic unit by a preferably rigid line, and the inner chamber of each hollow piston rod communicates with the cylinder chamber of the same hydraulic unit when the piston is fully extended.

Abstract: A turret deck for a telescopic conveyor comprises a platform which is longitudinally and translationally movable relative to the chassis of a vehicle on which it is supported. The platform supports a base plate and a supporting yoke on which the telescopic conveyor is pivotally mounted about a horizontal shaft. The conveyor is tilted by means of two hydraulic cylinders, one of which is located between the base plate and a second supporting yoke for placing the conveyor in a transport position, while the other cylinder tilts the conveyor to allow unloading. An additional hydraulic cylinder on the conveyor retracts automatically during operation of the first hydraulic cylinder in order to prevent the conveyor from interfering with obstacles or power lines while it is being placed in the transport position. The telescopic conveyor comprises devices for storing the lower band of the endless belt conveyor during the retraction of the various sections of the conveyor.

Abstract: An invalid lift and transport apparatus for safely lifting and transporting bedridden or wheelchair bound individuals with a minimum of effort and assistance is disclosed. The apparatus includes a movable mast assembly powered by a remote hydraulic pump. The mast assembly has an upright mast rotatable about a substantially vertical axis and a hydraulically extensible boom, for supporting an invalid carrying sling, pivotally joined thereto. A lift cylinder, joining the lower portion of the mast with the boom, is provided for raising and lowering the boom. A hand-held controller permits the invalid individual or attendant to extend, retract, raise, and lower the boom by selectively actuating the hydraulic components with the touch of a button. The mast may be similarly rotated. In operation, the sling may be readily moved to position an invalid seated therein to practically any position within the reach of the boom with a minimum of physical effort.

Abstract: A lift mountable in a transporting vehicle for loading and unloading objects such as small motorized carts. The lift includes an adjustable stand and pivotal boom assembly. An electric motor selectively operates a drum on which is wound a lifting cable or strap which terminates at a lifting hook or claw which is attachable to the cart or object. The adjustability of the stand and boom make the lift highly versatile and adaptable for convenient mounting in different vehicle configurations.

Abstract: A crane vehicle which reaches a minimum traveling speed of 62 km/h on public roads and gives the vehicle driver a range of vision with a radius of not more than 12 m comprises a vehicle frame which is substantially lowered to the level of the centers of the vehicle wheels, with at least part of the vehicle wheels being provided with hydrostatic individual wheel drives that are respectively arranged in the area of the wheel hubs. Furthermore, the crane vehicle comprises motor means for travel operation and crane operation, with said motor means being supported above the vehicle frame in a turntable which is supported on the vehicle frame in a horizontally pivotable manner. When viewed in the direction of travel, a driver's cab is mounted upstream of the motor means on the turntable, and a split longitudinal spindle which is mechanically lockable with the steering means for the vehicle wheels for travel operation is provided in the area of the driver's cab.

Abstract: Foldable link rod system to be placed on a travelling frame comprises pivotally suspended link rods (16, 18) for raising and lowering an operation platform (14). A rotating stool (20) constitutes the connection between two link rods (16 and 18) which are placed in continuation to each other. The one part of the rotating stool (20) is linked to the free end of the first link rod (16) which at its opposite end is pivotally linked to a swinging rod system (26, 28, 30, 32). The second link rod (18) is linked to the other part of the rotating stool and at its other end it is linked to the operation platform (14). The two link rods are pivotal by means of each of their swinging devices (54-70) which are supported on the travelling frame (10, 12) and the rotating stool (20), respectively.

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: The invention relates to a crane truck with a drivable undercarriage and a superstructure supported on the undercarriage to be rotatable by means of a slewing rim, the superstructure having a counterweight, which is movable by an elevating mechanism consisting of two piston-cylinder drives between an elevated operation position and a driving position when it rests lowered onto a support on the undercarriage. The piston rods of the piston-cylinder drives are drivable to rotate between a locking and unlocking position referred to the counterweight. The desired positions of the piston rods in their positions of crane operation and release as well as their locking and unlocking position are displayable by means of proximity switches on the piston-cylinder drives, so as to eliminate operation errors and disturbances in the hydraulic system of the piston-cylinder drives by way of various control units.

Abstract: A boom apparatus for use in lifting and transporting a payload includes a boom pivotally mounted on a support structure and including base and outer boom sections, the outer boom section being telescopically received within the base boom section and being movable axially relative to the base boom section. Sensors are provided for sensing the total length of the boom and the total moment load experienced by the boom, and an electrical warning and control circuit generates a warning signal either when the load as sensed is greater than a first predetermined value and the total length of the boom as sensed is less than a predetermined length, or when the load as sensed is greater than a second predetermined value and the total length of the boom as sensed is greater than the predetermined length, the second predetermined value of the load being less than the first predetermined value.

Abstract: A crane or lifting device includes a base assembly with a telescopic and rotatable column mounting a boom assembly including a telescopic boom arm. A strap is connected at one end thereof to the base assembly, extends through the boom arm, and is connected at another end thereof to a hook for engaging a load. An extensible/retractable jack assembly innerconnects the column and the boom arm for raising and lowering the boom arm. The crane can be mounted in an automobile trunk for raising and lowering the boom assembly.

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: Crane apparatus having a pendant control with two stage operational switches is provided for use with a control system for maximum precision and efficiency during operation. The two stage switches allow for fast or slow crane movement as required. Boom construction is also presented for easy manufacture and superior strength under load.

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 mobile crane is disclosed which comprises a telescopic boom, which is pivoted to the rotating superstructure or rotating deck of the crane and is adapted to be luffed by a luffing cylinder, which is pivoted to the boom and the rotating deck. A guying yoke is pivoted on the rear of the telescopic boom near the middle of its base box. Two axially aligned spaced apart rope pulleys are rotatably mounted at the outer end of the guying yoke. A reversing rope pulley is provided adjacent to the top end of the telescopic boom. Also, a winch is provided with a rope, which serves to guy the telescopic boom and extends around one rope pulley of the guying yoke to the upper reversing rope pulley and back around the other rope pulley of the guying yoke to a fixed point. The winch and the point to which the rope is fixed are disposed on mutually opposite sides of the telescopic boom adjacent to the pivotal axis of the boom.

Abstract: A relocating apparatus having a pivot connector for removably pivotally connecting the apparatus to a mast of a sailing vessel. The relocating apparatus also includes a telescoping sleeve assembly which supports a cable which can be connected to a load such as a dinghy. The cable is retracted about a drum which is rotated by a winch handle inserted in the relocating apparatus causing the dinghy to be raised. The relocating apparatus is swung about the pivot connecter to place the dinghy into position near a deck edge of the vessel. The telescoping sleeve assembly is then retracted or extended as desired by inserting the winch handle in a second socket and rotating the winch handle in the desired direction. After the dinghy has been located above the desired position, the cable is extended by inserting the winch handle in the proper socket and rotating the handle.

Abstract: A crane device is installed in a freight car with a roof and comprises a revolvable frame suspended by the roof so as to be revolvable about a vertical axis, a derrick boom assembly having a telescopically extendable boom and luffably supported by the revolvable frame, a winch mounted on the revolvable frame and operating to lower and raise a cargo hook via a length of wire rope, a control system using motive power to operate the crane device, and a safety system having a tactile sensor on the front end of the boom and operating to stop movements of the boom when the sensor contacts an object such as a part of a freight car or a piece of cargo. The winch is provided with a safety device for preventing excessive unwinding of the wire rope.

Abstract: An apparatus 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, rotatin

Abstract: A hoist for controllably lifting, holding or lowering an object from a mobile aerial device having an articulated or extendable boom supporting a man-lifting platform. The hoist has an adjustably positioned housing and positioning plate mounted to a shaft. The shaft is secured to the boom of the mobile aerial device, in proximity to the man-lifting platform. An elongated jib with sheave at one end is supported by the housing and may be linearly positioned in relation to the hoist housing. The housing may be manually positioned in relation to the positioning plate, and the positioning plate may be rotatably positioned in relation to the mobile aerial device boom by fluid control means. A rotary fluid motor is adapted to turn a drum about the hoist shaft and controllably wind or unwind a line about the drum. The line extends from the drum about a sheave rotatably secured to one end of the jib, and is of a length sufficient to extend to the object to be moved by the hoist.

Abstract: A crane is comprised a foundation, a supporting pole elongating vertically from the foundation, an arm capable of rotatably moving on a plane parallel with the supporting pole, and a winding drum mounted at the tip end portion of the arm, the arm consisting of two arms elongating in parallel with each other, the drum being mounted between two arms. The crane is installed on the rooftop of a building or the like and capable of effectively pulling up an object from a narrow road onto a narrow rooftop and setting it up on a rooftop.

Abstract: A pivoted arm counterbalance system for a self balancing crane provides a counterbalancing moment exactly equal to the overturning moment of the crane by the utilization of a dynamic balancing system in which a drive cable having a tension related to the tension of the support cable runs over and is secured to a constant radius sector secured to the counterbalance arm. The pivot point of the sector corresponds to the pivot point of the counterbalancing arm such that the constant radius sector provides a constant lever arm regardless of the counterbalance arm angle.

Abstract: Vehicular crane of high carrying capacity having an extensible arm, especially a telescopic arm. The vehicular crane has a maximum carrying capacity of greater than 250 metric tons obtained in such a way that, with a stroke length which is sufficient for the situation, the vehicular crane can be ready for use immediately after reaching the place of use without having to undergo expensive assembly procedures. The extensible arm of the crane is connected with an undercarriage via a frame part which carries pivot mounting. The crane is also provided with wheeled swivel supports as carrier supports which are provided with vertically adjustable ground support elements and undercarriage wheels of which the direction can be adjusted.

Abstract: An apparatus is disclosed for maintaining a predetermined mast-boom working angle of a pendant supported boom substantially constant during extension and retraction of the boom. One embodiment of the invention includes control means connected between the boom and the mast for detecting slight angular changes and actuating power means for paying out or drawing in sufficient pendant to return the mast-boom angle to a predetermined angle. Another embodiment utilizes electrical controls having a first potentiometer capable of detecting linear changes in the effective boom supporting length of the pendant and another potentiometer for detecting linear changes in the length of the boom, said potentiometer sending output signal ratios which vary from a predetermined output signal ratio for actuating power means that takes up or pays out sufficient pendant to return the boom to the predetermined mast-boom working angle and returns the output signal ratio to said predetermined ratio.

Abstract: This invention relates to a telescopic boom and conveyor apparatus which can be vehicle mounted. An endless conveyor belt is carried by a main boom which itself is telescopic. Optionally, an articulated boom can be attached to the free end of the main boom. Separate means is provided for the support of the main and articulated boom which automatically adjusts during telescopic displacement in order to maintain the main boom and articulated boom at predetermined angles. The angulation of the booms can be changed and the conveyor run while the main boom is undergoing telescopic displacement.

Abstract: A hoisting apparatus mounted on a vehicle and used to raise oil tubing from within an oil well casing or the like having a lower telescoping boom element that includes a lower secured member and a lower extending member oriented to extend in one direction, and an upper telescoping boom element that includes an upper secured member mounted on the lower extending member with an upper extending member oriented to extend in a direction parallel to but opposite from the one direction. A pulley allows a lifting cable to depend from the lifting end and a lifting cable extends from the extended free end of the upper extending member to the first pulley so that the lower extending member can be extended to position the lifting cable and the upper extending member can be extended to raise the lifting cable.

Abstract: A Compact Heavy Duty Lifting Crane (CHDLC) for removing and installing heavy objects such as engines and transmission from vehicles. The CHDLC incorporates a feature that allows the vertical lifting angle of the telescoping boom (40) to remain constant as the telescoping pylon cylinder (18) is raised. This feature is particularly useful for removing engines located in limited-space engine compartments such as those encountered in vans and buses. The CHDLC consists of two major assemblies: a base assembly and a portable lifting crane. When the CHDLC is used as a standard utility crane in a repair shop the crane is mounted to the base assembly. When the CHDLC is required to be mounted on a truck bed the crane is removed from the base assembly and installed on a truck pylon plate (14a) that is permanently mounted to the bed of the truck. Additionally, the CHDLC may be placed in its storage configuration. In this configuration the CHDLC occupies a horizontal area of only four square feet.

Abstract: Supplementary equipment for use with a self-propelled crane with a telescopic jib to increase the possibilities of use of the crane on the ground comprising a support having a structure connected to the head of the jib and pivotally mounted on a platform of the crane, and an auxiliary jib articulated on the head of the jib. A strut is articulated at one end to the foot of the auxiliary jib and connected at its outer end to reeving articulated on the crane and controlled by a first winch and by a cable to the head of the auxiliary jib. A lifting hook is suspended by reeving from pulleys at the head of the jib and controlled by a cable connected to a second winch on the crane. The inclination and height of the auxiliary jib are controlled by the reeving and the first winch connected thereto, and angular movement of the jib about the vertical axis or pivotal movement of the structure on the platform is controlled by movement of the crane about that vertical axis.

Abstract: A coupling and latching mechanism for a multisection extensible boom that includes a manual section and is operable from a remote location such as the cab of a crane. The mechanism includes pairs of spaced jaw type couplings secured to adjacent boom sections and adapted to be selectively coupled to the piston rod or the like of an extensible power means for operating the boom either with the manual section extended or retracted. Remotely controlled latch means are provided to latch the manual section in a plurality of extended positions, or in a retracted position.

Abstract: An apparatus is disclosed for maintaining a predetermined mast-boom working angle of a pendant supported boom substantially constant during extension and retraction of the boom. One embodiment of the invention includes control means connected between the boom and the mast for detecting slight angular changes and actuating power means for paying out or drawing in sufficient pendant to return the mast-boom angle to a predetermined angle. Another embodiment utilizes electrical controls having a first potentiometer capable of detecting linear changes in the effective boom supporting length of the pendant and another potentiometer for detecting linear changes in the length of the boom, said potentiometer sending output signal ratios which vary from a predetermined output signal ratio for actuating power means that takes up or pays out sufficient pendant to return the boom to the predetermined mast-boom working angle and returns the output signal ratio to said predetermined ratio.

Abstract: A telescopic boom is disclosed which is pivotally supported by its base section for movement about a horizontal axis. The boom is supported by a live mast through multi-part pendant lines, which pendant lines are each reeved over sheaves attached to the boom at the forward end of the base section and at the forward end of another boom section to support the boom at a plurality of points forwardly of the live mast. The forward end of each pendant is preferably received within the boom over sheaves journaled on the cylinder case of a boom extending ram and on selected sections of the boom. The multi-part pendant supported boom reduces boom droop caused by extension of the boom approximately 50% of that of a boom supported at a single point by each pendant line.

Abstract: A truck for towing disabled vehicles is provided with a cab controlled or a remote controlled vehicle lifting assembly including pairs of claws which will automatically engage a pair of the wheels of a vehicle and enable the vehicle to be lifted and towed, the vehicle being carried on its own suspension system during towing. The assembly includes a crane mounted and arranged so that the load thereon is carried forward of the rear axle of the tow truck--this increases the tow capacity of the truck and provides stable operation of the crane. The claw assembly may be locked by a ratchet and strap arrangement which retains the vehicle wheels in the assembly in their forward position and prevents release due to jolts and bouncing.

Abstract: A pendant control system for pendant supported multi-section telescopic boom is disclosed for paying out or hauling in sufficient pendant rope in response to detecting changes in the boom-mast angle from a desired angle Y thereby preventing the free end of the boom from raising due to extension and dropping due to retraction of the boom when the outer end of the boom is supported by pendant ropes. The system also provides means for pivoting the mast between a raised boom supporting position and a lowered transport position while maintaining tension on the pendant lines.

Abstract: A mobile crane or aerial lift platform vehicle wherein the chassis comprises a horizontally disposed solid metal slab carrying axle/outrigger mountings and on which the boom or jib turntable is mounted. This has the advantage both of providing stability because of the weight of the solid chassis and of cheaper fabrication and assembly.

Abstract: A hydraulic control system which is of an open center parallel circuit arrangement for aerial boom devices with two return lines, said system having control valves for upper and lower boom arms, wherein the lower boom control valve overrides the upper boom control valve. The system includes a valve connected to a pump actuating engine and responsive to hydraulic pressure to increase the speed of the fluid pump when the flow or pressure in one return line is reduced due to diversion of fluid within the system into the second return line. The system also includes a normally open relief valve carried by the boom supporting turntable adjacent its pivotal connection to the lower boom and operable to control a winch actuator and to deactivate said winch actuator when the boom is in an unstable position.

Abstract: The apparatus includes a mobile chassis having a turntable on which is supported a boom assembly. At the free end of the boom assembly is tiltably mounted a forklift carriage which can be extended and retracted relative to the boom assembly.

Abstract: A crane with a telescopic extensible boom is disclosed. Two cylinders within the boom are each connected between adjacent sections for relative movement between the sections. Pendants are trained over sheaves on a live mast, and one end of the pendants is held by a stop on the mast. The other end of the pendants is received in the boom over sheaves mounted in fixed relation to the respective crane sections. The opposite end of the pendants is connected to the base section of the boom.

Abstract: A pair of hydraulic locking cylinders for a vertically oscillatable wheel axle on the carrier frame of a mobile crane are interconnected and controlled by a hydraulic double-locking valve which is responsive to the centered or off-centered rotary position of the boom-carrying rotatable upper section of the crane. The double-locking valve comprises a pair of normally closed ball-type check valves which are operated by a valve stem comprising independently movable upper and lower sections. The upper valve stem section is positioned by a cam on the crane upper section and the lower valve stem section is positioned by a pneumatic actuator which is controlled by a solenoid valve selectively actuatable by an electric override switch in the crane operator's cab. The upper valve stem is moved to down (valve open-axle unlocked) position by the cam when the crane upper is centered on the carrier frame. The upper valve stem moves to up (valve closed-axle locked) position when the crane upper is rotated off-center.

Abstract: A towing vehicle with a boom pivotal about a horizontal axis and a second axis perpendicularly thereto enabling the boom to be moved to a position over a disabled vehicle located along side the towing vehicle. A pair of power cylinders is attached to the boom and is operable to swing the boom with load attached to locate the load or disabled vehicle immediately behind the towing vehicle. An elongated support is movable downwardly against the ground behind the towing vehicle to provide stability as the load is lifted and swung from a position aside the towing vehicle to a rearward position.

Abstract: An excavator having a boom with slidably engaging base and beam parts is disclosed. The base part is mounted on a support part of the excavator for rotation about a horizontal axis; and a dipper arm which carries an excavating tool is pivotally suspended from the beam part. The base and beam parts are joined by channel section guides which permit sliding movement between the parts. A wedge member releasably fixes the relative position of the base and beam parts by wedgingly engaging both parts.

Abstract: Apparatus enabling access to the interior surfaces bounding a large spaced comprises a pole adapted to extend vertically through the height of the space with its lower end located at the base of the space, at least one boom structure connected with said pole, a working platform connected to the end of said boom structure remote from said pole and the height of said boom structure is adjustable relative to said pole.