GB2612887A

GB2612887A - Crane arm and system

Info

Publication number: GB2612887A
Application number: GB2213207.0A
Authority: GB
Inventors: Adam Kogut Jakub; Carlsen Torleif
Original assignee: Emox AS
Current assignee: Emox AS
Priority date: 2021-09-09
Filing date: 2022-09-09
Publication date: 2023-05-17
Also published as: GB202213207D0; NO347680B1; NO20211087A1

Abstract

A crane arm has a quick connect/disconnect member 151, such as a pin, for connecting/disconnecting the crane arm to a supporting structure 8, such as a wall. The crane arm may have guide means P1, from which a lifting line 25 is suspended in a loop 44 from the crane arm and may be movable longitudinally along the crane arm. The guide means being may guide first 25a and second 25b sections of the looped line so that forward and rearward components of force are imparted to the guide means from the lifting line. The crane arm may include an actuator, such as a winch 30a or linear actuator 30b which may have a screw thread 32. The crane arm may also have a support element P4 that is movable along the crane arm for varying the suspended length of the lifting line. The crane arm may be carried and have a handle 12 or a shoulder strap.

Description

CRANE ARM AND SYSTEM

The present invention relates to cranes and hoists and in particular to crane arms and related apparatus and systems.

Cranes and hoists of various kinds can be an important utility in many settings. In various workspaces, such as inside buildings, workshops or other work areas or facilities, traditional crane or hoisting solutions may not be suitable or convenient. For example, the structure of a building itself may limit the kinds of cranes or hoists that are suited. There may also be few suitable crane or hoist locations in busy workplaces for example where many other items of equipment, structures, furniture, or machines are present. Moreover, some workspaces may not allow use of a crane, where this otherwise might be of interest to help with certain lifts. If there are available locations, such locations may need to be adapted or structurally reinforced for the crane or it may not be possible to install the crane in an optimal position. There is generally therefore a need for improved crane or hoisting solutions. At least one aim of the invention is to obviate or mitigate one or more drawbacks of prior ad.

According to a first aspect of the invention, there is provided a crane arm comprising a quick connect/disconnect member for quick-connecting the crane arm to a supporting structure or quick-disconnecting the crane arm from the supporting structure.

In this way, through the quick connect/disconnect member, the crane arm may be readily connected to or disconnected from the supporting structure. The crane arm may be manually lifted and supported in position for quick-connection and manually supported and lowered for quick-disconnection.

The crane arm can be held by hand in position to connect or disconnect the crane.

Typically, the quick connect/disconnect member is provided at or near a supporting end of the arm. Alternatively, the quick connect/disconnect member provided at an intermediate arm portion, between ends of the arm.

The quick connect/disconnect member may be configured for connecting and/or disconnecting the crane arm to the supporting structure without tools.

The quick connect/disconnect member may be configured for connecting and/or disconnecting the crane arm to the supporting structure by handling the crane arm only.

The quick connect/disconnect member may lockably engage with a member of the supporting structure.

The crane arm may be connectable, and optionally lockable, with respect to the supporting structure through urging, pushing or otherwise manipulating the quick connector into mechanical engagement with a member of the supporting structure. The quick connect/disconnect member may engage in a snap fit or click fit to the member of the supporting structure.

The quick connect/disconnect member may be configured to be connectable, and optionally further configured for lockably coupling the crane arm, to the supporting structure, so that the crane arm cannot be disconnected or released from the supporting structure without pre-action.

The crane arm may have a pre-action member for performing a pre-action for allowing the crane arm to be disconnected or released from the supporting structure. The pre-action member may for example comprise any one or more of: a button, a lever, a safety pin, or a lock member. The pre-action member may be operable to transmit a signal to an actuator to perform the pre-action, e.g. unlocking the lock member, removing safety pin, pulling a release cord, etc. The pre-action member may transmit a mechanical force to a release element to perform the pre-action.

The quick connect/disconnect member may comprise any one or more of: a clamp, a suction cup; a hook; a bracket; a sleeve; a hanger; a shoulder, a groove; a slot; a clip; a press-fitting; a popper; or a ring. The quick connect/disconnect member may comprise a sleeve arranged to engage with a corresponding pin member of the supporting structure.

The quick connect/disconnect member may be further configured for rotary coupling the crane arm to the supporting structure. For example, the quick connect/disconnect member may comprise a pin configured to be received through a sleeve of the supporting structure so as to be rotatable within the sleeve and relative to the supporting structure. Accordingly, the crane arm may be rotated about the longitudinal axis of the pin relative to the supporting structure.

In one particular example, the crane may be configured to be coupled via the quick connect/disconnect member to the supporting structure so as to have a first configuration, in which the crane arm may be connected upon the support structure to form a cantilever extending from the support structure for performing lifts and in which the crane arm may be rotatable with respect to the supporting structure about a first axis, e.g. vertical axis, and a second configuration in which the crane arm may be pivotable to a stowed position about a second axis, which typically is perpendicular to the first axis, e.g. a horizontal axis. The crane arm may thus be positioned in the stowed position so that a longitudinal axis of the crane arm is e.g. vertical when the crane arm is not in use.

The quick connect/disconnect member may comprise at least one hang-off element for hanging the crane arm from the hang-off element in the stowed position. The hang off element may be a hooking element. The hooking element may be a pin. The pin may be configured to couple to a corresponding sleeve on the supporting structure. The hooking element may be arranged to engage with a corresponding member of the supporting structure. The member of the supporting structure may comprise a guidable plate to funnel and position lock pins. The pin may be a spring-loaded locking element.

The hang-off or arrangement in stowed position can facilitate safe mounting of the crane arm upon the supporting structure. The crane arm can be initially positioned upon and coupled to the supporting structure in the stowed position, and then pivoted upward from the stowed position and further coupled to the supporting structure in the use position. By separating the manipulation steps of initially coupling the crane arm to the supporting structure and/or moving the crane arm into the use position arranging the crane arm may be easier for one person to handle and safer.

Advantageously, the quick connect/disconnect member may facilitate disconnecting the crane arm from the support structure in one location and connecting to another support structure in another location, for instance another location within the same workspace. Tool-free connect/disconnect can facilitate speedy and safe repositioning of the crane arm from one support structure to another.

The crane arm may be configured to facilitate being carried by a person when not in use. To this end, the crane arm may have at least one grip portion. The crane arm may have at least one carry handle. Alternatively or in addition, the crane arm may be provided with at least one strap, for example a shoulder strap. The crane arm may be provided with a pair of straps to be passed over respective shoulders of the person for carrying the crane arm as a backpack. The crane arm may have at least one pad, e.g. for resting the crane arm against at least one body part of a person, e.g. for resting upon, gripping and/or carrying the crane arm on a shoulder or other part(s) of the person.

The crane arm is preferably constructed using only lightweight and/or low-density materials. The low-density materials may comprise materials with density of equal to or less than 5 g/cm3. The crane arm may have a weight of 40 kg or less, 30 kg or less, 20 kg or less, or 10 kg or less. Typically, the weight is in the range of 20 to 30 kg. The weight may preferably be 25 kg or less if the crane arm is to be handled by one person only. In other cases, the crane arm may be greater than 25 kg. The crane arm may be of any weight and size that may allow it to be readily carried, relocated, and installed manually by personnel.

Preferably, the crane arm further comprises at least one support element that is movable along the crane arm for varying the suspended extent of the lifting line from the crane arm in a direction transverse to the longitudinal direction.

Further preferably, the crane arm further comprises guide means from which a lifting line is suspendable in a loop from the crane arm, the guide means being movable along the crane arm for obtaining a desired position of suspension of the lifting line; the guide means being configured to guide first and second sections of the looped line through the guide means, so that a rearward component of force is imparted to the guide means by one of the first and second sections of line and a forward component of force is imparted to the guide means by the other of the first and second sections of line.

Advantageously, the crane arm may in various embodiments facilitate mobility of the crane arm, allowing it to be moved readily from one location to another and be conveniently provided when and where required.

According to a second aspect of the invention, there is provided apparatus comprising: the crane arm according to the first aspect of the invention; and a support structure; the crane arm being configured to be coupled to the support structure via a quick connect/disconnect coupling.

The support structure may comprise a wall or a ceiling. The support structure may comprise a member for cooperating with the quick connect/disconnect member of the crane arm.

According to a third aspect of the invention, there is provided a crane arm comprising: guide means from which a lifting line is suspendable in a loop from the crane arm, the guide means being movable in a longitudinal direction along the crane arm for obtaining a desired position of suspension of the lifting line; the guide means being configured to guide first and second sections of the looped line through the guide means, so that a rearward component of force is imparted to the guide means by one of the first and second sections of line and a forward component of force is imparted to the guide means by the other of the first and second sections of line.

Typically, the crane arm includes or is provided with the lifting line.

Typically, the first section of the line extends through the guide means from a region rearward along the crane arm with respect to the guide means and the second section of the line extends through the guide means toward a region forward along the crane arm with respect to the guide means.

Typically, the guide means comprises a cross-over for the first and second sections of line. In examples where the guide means comprises the crossover, the first section of the line extends through the guide means from a region rearward along the crane arm with respect to the guide means to impart a component of force to the guide means in a rearward direction, the second section of the line extends through the guide means toward a region forward along the crane arm with respect to the guide means to impart a component of force to the guide means in a forward direction. In this configuration, the components of force exerted by first and second sections of the line may place the guide means under compression between the line sections in the longitudinal direction of the crane arm.

Advantageously, the imparted force components in forward and rearward directions, e.g. opposite directions, along the crane arm from the looped sections of the lifting line can facilitate distribution and/or balancing of forces of the lifting line against the guide means from the suspended load. The lifting line may run along the crane arm and be suspended over the guide means, such that the resultant force (i.e. sum of components in forward and rearward directions) exerted upon the guide means along the crane arm when the lifting line is under load is minimal. Small resultant or residual forces may reduce risk of failures in parts of the crane arm and may make it possible to manipulate the guide means manually along the crane arm even when under substantial loads suspended upon the lifting wire.

The guide means may comprise a guide block, idler, sheave wheel, channel, groove, or other member. A section of the lifting line may occupy. The channel may comprise a curved surface for guiding the line from a trajectory along the crane arm to a trajectory transverse to the crane arm.

The loop of the lifting line is arranged to support an idler at an apex of the loop suspended from the crane. The looped line may extend through the idler. The idler may be provided with a hook or other connector for connecting the lifting line to a load for lifting/lowering the load using the crane arm.

The crane arm may reach longitudinally between one end, e.g. a first, supporting end, toward another end, e.g. a second end. The region rearward of the guide means may be a region near the first end of the crane arm and the region forward of the guide means may be a region near the second end of the arm. The crane arm may be coupled to a supporting structure through the first end and the second end may be a free end.

The crane arm may comprise one or more elements along the trajectory of the lifting line to change the trajectory of the lifting line through the crane arm. The one or more elements may comprise one or more idlers.

The guide means may be arranged to roll freely along the crane arm, e.g. on a track, e.g. on bearings. Through forces imparted to the guide means acting in opposing forward and rearward directions, under gravitational load at an end of the suspended lifting line loop, the position of the guide means along the crane arm may be maintained. Consequently, no lock or brake is needed to keep the first pulley in a desired position. When an operator wants to move a load in a horizontal direction, the operator may only use a limited force to pull or push the load and/or the guide means so that the guide means is moved, e.g. rolled along the crane arm in the longitudinal direction.

The guide means may be movable along the crane arm, for example manually or electrically. Due to the configuration of the lifting line through the guide means, movement the guide means in the longitudinal direction can be achieved by overcoming minimal force in the longitudinal direction, also when the crane has a heavy load suspended upon the lifting line loop.

The guide means may be steplessly movable along the first axis.

The crane arm may have an elongate main body extending in the longitudinal direction and the guide means may be supported upon the main body.

In certain variants, the main body may have an open structure. The open structure may be longitudinally extending beam. The beam may be any of: an I-beam, an L-beam, a J-beam, or a U-beam. The lifting line may follow a trajectory adjacent to one or more of the open structure. The crane arm may have one or more panels arranged on an outside of the open structure to cover the path of the lifting line at least partially. The one or more panels may thus shield the lifting wire on the crane arm from external interactions and improve personnel safety, and may serve to provide water, particle and/or dust protection.

In certain other variants, the main body may have a closed structure. In such variants, the lifting line may comprise an inboard portion and an outboard portion, wherein the inboard portion may comprise a length of the lifting line through the rearward region to the guide means and a length of the lifting line from the guide means and on through the forward region. The outboard portion may comprise the suspended loop of line that may be payed out from the guide means. When the body has a closed structure, the lifting line may in its entirety be stored inboard, inside the main body. In use, the lifting line may be stored inboard except for the suspended loop of line hanging from the guide means. As much as possible of the cable may then be protected from external human and non-human interactions and may serve to provide water, particle or dust protection.

The main body in the variants having the closed structure, may comprise side panels, and optionally also one or more top panels to extend between the side panels, and optionally also one or more bottom panels to extend between the side panels. The side panels may be bolted together. The panels may define at least one recess. The panels may comprise at least one edge being angled relative to the side panel. The edge may increase the strength of the side panel. Each of the two side panels may comprise an edge arranged to be connected to the other edge.

According to a fourth aspect of the invention, there is provided a system comprising a supporting structure and the crane arm according to the third aspect of the invention, the crane arm to be coupled to the supporting structure.

According to a fifth aspect of the invention, there is provided a crane arm comprising: at least one support element that is movable in a longitudinal direction along the crane arm for varying the suspended extent of the lifting line from the crane arm in a direction transverse to the longitudinal direction.

Typically, the crane arm has at least one actuator operable to produce the movement of the support element along the arm. The actuator is preferably a linear actuator.

The actuator preferably comprises an actuator rod extending along the crane arm, the actuator rod being operable to produce movement of the support element.

More preferably, the actuator rod is a threaded screw rod. The threaded rod may extend through and engage a complementarily threaded sleeve or ring and may be rotatable relative to the threaded sleeve or ring so as to advance the rod through the sleeve or ring for moving the support element along the crane arm.

The linear actuator may include the support element. The support element may comprise a guide for the lifting wire. The support element or guide may be a cylindrical element or an element defining an arc for the lifting wire around or through the support element. The lifting wire may be secured fixedly to the support element. The support element may comprise an idler, e.g. an idler wheel.

In variants where the actuator is a threaded screw rod actuator, the support element may be moved along the threaded screw rod when the screw rod rotates. In examples using the threaded screw rod actuator, respective ends of the lifting line may be fixed to the main body and the lifting line is not wound onto a drum.

The linear actuator may be used to position the one or more support elements to manipulate the lifting line trajectory for shortening or lengthening the suspended extend of the lifting line, e.g. part of the lifting line hanging from the crane arm from the guide means. The lifting line may be configured to be guided through one or more support elements on the main body of the crane arm. The path may be configured or arranged in dependence upon or determined at least in part by the position(s) of the one or more support elements on the crane arm. Using the actuator to manipulate the one or more support elements may accordingly allow the power ratio conveniently to be adjusted. Movement of a support element along the main body of the crane arm may reduce or extend the suspended length of the lifting line. Movement of the support element along the main body of the crane arm may be pre-configurable to reduce or extend the lifting line and may thus also allow power conversion.

Advantageously, the screw rod actuator can have a high input torque to lift force ratio. The screw rod actuator can facilitate a low friction hoist drive that may in turn reduce the required power input. Thus, the actuator may be driven by a small low-torque motor with a direct drive, a small low-torque motor including an inline gear, an external electric power input such as battery drill or even manual crank or belt drive action, chain drive action or bead drive action, yet these may produce a high lift force.

The screw rod actuator can advantageously provide precise and stepless lift movement. The screw rod actuator may be operated under automatic control, e.g. by execution of a computer program, or under remote control for operating the motor for driving the screw rod actuator for lifting/lowering a load connected the suspended length of the lifting line.

The crane arm may include a further actuator to adjust the position of the guide means longitudinally along the crane arm. The further actuator may be a further screw rod actuator operable to urge the guide means along the crane arm. The further screw rod actuator for positioning the guide means may be operable separately from the screw rod actuator for positioning the support element for varying the suspended extent of the lifting line. The screw rod actuator and the further screw rod actuator may by operated by separate motors. The motors may be electric motors. The motors may be electronically controlled. The motors or motor control electronics may be adapted to receive control signals, e.g. wirelessly from a remote transmitter.

The actuator may in an alternative embodiment be a linear tooth rack actuator. The crane arm may include a screw rod linear actuator and tooth rack linear actuator.

In some variants, the actuator may comprise first and second actuators wherein the first actuator may be a winch. It may be useful for a portion of the cable be rolled onto a drum of the winch if the available route for the lifting wire inboard upon the crane arm is less than the full length of the cable, e.g. for full hoisting range on the lifting line to be suspended. This may in turn allow one to configure the crane arm with relatively few elements for guiding the lifting line and a relatively short trajectory inboard of the crane arm. The winch may also facilitate providing a longer outboard length of lifting line and for providing greater or adding to the suspended extent beyond that provided from linear extension of a linear actuator.

The at least one actuator may be connected to a transmission and the transmission may be connected to an energy source. The transmission may comprise a worm drive. In variants where the actuator comprises a linear screw rod actuator, the screw rod may be a worm screw for engaging with a worm wheel. The worm drive may thus be suitable in combination with the screw rod linear actuator. The transmission may be advantageous in that a low input torque from the energy source may be transferred to a high output torque for the first actuator. Furthermore, the worm drive can have a drive line which may be self-locking. The self-locking of the drive line can facilitate to avoid the load applying an uncontrolled motion if the power is cut or if the manual torque input is disconnected. The worm drive may also advantageously transfer a motion by 90 degrees.

The first and/or second actuators may each be connected to a transmission which may comprise a worm drive. In variants where the second actuator is a linear screw rod actuator, the screw rod may be a worm screw for engaging with a worm wheel.

The transmission may be arranged for being connected to an energy source outside the crane arm. This may allow the energy source to be disconnected to reduce the net weight of the crane during relocation. Furthermore, alternative energy sources may be used to operate the actuators for operating the crane arm.

The energy source may be a battery. The energy source may be a stationary power supply. The energy source may be a manual crank operation. The energy source may be a handheld drill. This may allow the user to use an existing tool for operating the crane arm, utilising existing tools and reducing the investment whilst increasing redundancy and contingency by having rapid available drives and energy sources.

The energy source may be detachable. The energy source may be connected to the crane arm and may be detachable from the crane arm. The energy source may thus be arranged for replacement. This provides a quick turnaround with respect to failure and / or maintenance. The energy source can be replaced quickly to prevent added downtime. The energy source may also provide power output that may be used as source for an inductive remote control charging, or serve as a generic power outlet. The energy source may be modular. It may therefore have removable parts which may be replaced. The crane arm can have solar panels for charging the battery.

The energy source may comprise at least one of the following elements: motor, motor controller, additional electronics, cables and connectors and battery.

If the crane is used in a remote setting, on for instance an offshore rig or a vessel, only the energy source may be required to be shipped in or out in case of service.

The energy source may be a manually operated crank. The energy source may be not electric. In areas with electric drive restrictions such as Explosion Hazardous Areas, an electric drive line can advantageously be quickly replaced with the manually operated crank for allowing manual operation of the crane arm, or high-speed options such as a chain drive, belt drive or bead drive where linear movement of the manually operated actuator can result in a corresponding high rotation speed. In this way, operation is possible in restricted areas despite the restrictions.

The electric drive line may comprise a detachable battery, which may advantageously add flexibility and reduce failure turnaround times, e.g. when fixed power is lost. It also allows the crane arm to be installed in locations where electric infrastructure is absent or when electrical operation is not a viable option, for instance when the crane arm is mounted on a container on a vessel deck or other mobile platforms.

An electric drive can be used for driving the at least one actuator. The electric drive may allow remote and safe crane operation. For example, the user may operate the crane arm via wired or wireless communication. Operation using wireless communication may be possible using a control panel, dedicated remote device, or via an app on a smart phone or a tablet. The control panel may be positioned on the crane arm. The control panel may be detachable from the crane arm. The remote operation may allow the operator to operate the crane and still having a hand free to manipulate the lifted load.

The crane arm may comprise a torque limiter ensuring that the crane is not overloaded. The torque limiter may be electric. The torque limiter may be mechanical.

The guide means may be connected to a linear actuator, e.g. second linear actuator, extending between the first, coupling end and the second, free end of the crane arm. The linear actuator for the guid means may be linear actuator having a screw rod where the guide means may be movable longitudinally along the screw rod when the second screw rotates. The suspended load upon the lifting wire can be moved in the longitudinal direction, which in use is typically a substantially horizontal direction, by use of a motor or other drive means. The motor may be an electric motor. The second actuator may be connected to a transmission, and the transmission may comprise a worm drive or other gearing such as planetary gear.

The crane arm may comprise a control system for operating the at least one actuator, for example the first and second actuators.

In certain examples, the crane arm comprises a longitudinal guide rail and the guide means may be arranged to travel along the guide rail. The guide rail may comprise a tooth rack and the guide means may travel along the tooth rack through a tooth wheel in engagement with the tooth rack. In examples where the guide rail comprises a tooth rack, the tooth wheel may be operated to rotate along the tooth rack by a motor and stopped in desired position. The engagement by the teeth may then serve as a locking feature to facilitate preventing undesired movement of the guide means and/or load suspended therefrom along the crane arm. The tooth gear may comprise manual or electric driven spur gear in engagement a static rail tooth rack or isolated static tooth rack.

The guide means may be locked in position longitudinally to the crane arm or main body thereof. The longitudinal lock can be obtained, without the tooth rack or linear actuator. For example, the guide means may be locked with a safety pin or other manual mechanism.

The crane arm may have a control system arranged for remote control and/or remote service. The crane or crane arm may be operable by smart control. The smart control may be provided using a computer device over WIFI or Wireless communication network for facilitating maintenance notification, remote service, troubleshooting and/or SW/firmware upload and upgrading.

The crane arm may include a load sensing means in the crane arm. The crane arm may be equipped for loT connectivity. The control system may be operable to automatically generate weight reports or other performance reports. The smart control system may be further configured for test mode operations of the crane or for remote maintenance intervention purposes.

The control system may be configured to operate the crane in test mode to perform automated and/or set functions. Such functions may be repeatedly performed lifts, e.g. in a friction test.

Status information may be communicable to other nearby or remote smart devices. The control interface may be adapted to communicate and/or transmit data over suitable communication networks, such as Blue tooth, WIFI, or radio frequency networks, as may be necessary to conform to the various national regulations, including regulations that may include pairing requirements.

The crane arm may comprise at least one light for illuminating a working area and object being or to be lifted. This may facilitate operation in low light or night-time conditions. The light may be remotely triggered.

According to a sixth aspect of the invention, there is provided a system comprising a supporting structure and a crane arm according to the fifth aspect of the invention, wherein the crane arm is coupled to the supporting structure.

The supporting structure may comprise at least one member, e.g. a base element, which may be connected to a stationary element. The stationary element may for instance be a wall, a floor, a ceiling, or a structural member.

The supporting structure may comprise at least one member may be connected to a displaceable or movable element. The movable element may for instance be a vehicle, a semi-stationary base plafform with a fork trolley interface, a pallet or an idler wheel.

The crane arm may be positioned upon and/or coupled to any suitable supporting structure or element thereof. The supporting structure may comprise at least one member which may allow the crane arm to be easily coupled, decoupled, and/or repositioned to different locations, e.g. as needs arise.

The crane arm may be readily separable from the supporting structure, which may facilitate easily handling and repositioning of a low-weight crane arm in another location without requiring the supporting structure to be moved to other location.

The supporting structure may be a wall base fitted with a wire pulley system to enable a controlled vertical hoist of the crane arm, to position the crane arm up to an elevated base level. The wire pulley may also be used to ensure a controlled and descent of the crane arm during dismount or relocation.

The supporting structure may comprise a rotational lock providing a physical restraint to prevent an uncontrolled crane motion during operation. The lock may prevent movement of the crane rotationally, e.g. about a vertical axis and/or horizontal axis in use, upon the support, e.g. when the crane arm is rotationally coupled to the supporting structure. This may facilitate to handle uncontrolled crane motions as may for instance appear if the crane is used on a vessel in motion, e.g. upon a rig or ship at sea. The rotational lock may be a manual, electric or pneumatic rotational lock. The rotational lock may be direct and/or remotely controlled.

The supporting structure may comprise an intermediary member for coupling the crane arm to a further support structure, or base. By way of the intermediary the reach of the crane arm may be increased.

The crane arms in accordance with any of the first, third and fifth aspects of the invention may have any one or more further features as described in relation to any of the other of the first, third, and fifth aspects of the invention, wherever described herein.

There will now be described, by way of example only, embodiments of the invention with reference to the accompanying drawings, in which: Figure 1 is a schematic side representation of a crane arm; Figure 2 is a schematic side representation of another crane arm; Figure 3 is a schematic side representation of another crane arm, Figure 4 is a schematic side representation of another crane arm; Figure 5 is a close-up representation of movable guide means in the form of an idler wheel illustrating details of a track bed for a lifting wire of the arm; Figure 6 is a close-up representation of movable support element in the form of an idler wheel illustrating details of a track bed for a lifting wire of the arm; Figure 7 is a representation of possible coupling configurations A to E for a crane arm of Figures 1 to 4, the crane arm being coupled to a ceiling or overhead structure; Figure 8 is a representation of possible coupling configurations F to I for a crane arm of Figures 1 to 4, the crane arm being coupled to fixed wall or floor structures; Figure 9 is a representation of possible coupling configurations J to M for a crane arm of Figures 1 to 5, the crane arm being coupled to movable floor standing structures; Figures 10A to 10C are representations of the crane arm of any of Figures 1 to 4 in different stages of couplement to a wall-based supporting structure; Figure 11 is a representation of a crane arm of Figures 1 to 4 in side view and a bracket in perspective view showing quick-connect/release details; Figure 12 is a larger scale top view of the quick connect pin of the crane arm in the circle Y of Figure 11; and Figure 13 is a smaller scale side representation of a crane arm showing details of the rotational lock for locking the crane arm with respect to the supporting structure in use; Figures 14A to 14C are representations of a crane arm in different stages of couplement to a wall-based supporting structure; and Figure 15 is a representation of the crane arm of Figures 14A to 14C in side view and a bracket in perspective view showing alternative quick-connect/release details; With reference first to Figure 1, a crane arm 1 is coupled to a supporting structure 2 which in this example comprises a base element 2 that is fixedly mounted to a wall 8. The crane arm 1 extends longitudinally away from the wall from a first, coupling end 101 to a second, free end 102.

The crane arm 1 is coupled to the wall 8 via a quick connect/disconnect coupling, generally denoted 50. The crane arm 1 has a quick connect/disconnect pin member 151 to interlock with a corresponding formation 157 of the base element 7. In order to make up the coupling 50, the pin member 151 is located in the connecting position by aligning and manipulating the end of the crane arm into place.

The crane arm 1 has an elongate main body 10 which has first and second end portions 101, 102. The first end portion 101 is a coupling end portion, and the second end portion 102 is a free end portion. The main body 10 extends in a longitudinal direction from the first end portion 101 to the second end portion 102. The first, coupling end portion 101 is connected to a base element 7. The crane arm 1 is provided with a lifting line in the form of cable 25 which is routed partially inboard and partially outboard 22 of the main body 10 of the crane arm 1. The outboard length 22 of the cable 25 forms a loop 44 to which a load, i.e. an object, to be lifted is connected for suspending the load from the crane arm 1.

The outboard cable 25 in the loop 44 passes around a hook idler wheel P9.

The hook idler wheel P9 is arranged to be connected to a hook or other means arranged for connecting to a load.

The crane arm 1 has movable guide means P1 comprising idler surfaces for supporting the cables in bearing relationship thereupon. The cable 25 is suspended from the crane from the guide means P1 in the direction vertically transverse to the long axis X1 of the crane arm.

A first portion 25a of the suspended length L of the lifting cable 25 passes over an idler surface of the guide means P1 toward the first end portion 101 of the crane arm, and a second portion 25 b of the suspended length L of the lifting cable 25 passes over an idler surface of the guide means P1 toward the second end 102 of the crane arm 1. The first and second portions 25a, 25b of the cable therefore cross over at the guide means P1 and exert components of force, indicated by arrows N, M, against the guide means P1 in opposite directions along the longitudinal direction X1 of the crane arm 1.

The guide means P1 is arranged movably on the main body 10 of the crane arm. The guide means P1 is movable along the main body 10 between the first, coupling end portion 101 and the second, free end portion 102. The guide means P1 is movable along the crane arm therefore to position the guide means and hence the suspension point for the wire in desired position along the crane arm. This can facilitate positioning the load when in use.

Moreover, the since the forces M, N are balanced, the guide means may be moved without being exposed to or having to overcome large lateral forces, even when large loads are suspended. A vertical force Fl transferred from the hook idler P9 to the guide means P1 is in effect equalized along the longitudinal axis Xl. In certain variants, the guide means is moved along the crane arm by hand or other suitable means.

In the example of Figure 1, the guide means P1 is movable and lockable in certain pre-defined positions along the crane arm 1. The main body 10 has locking holes 14 which are provided for receiving a locking pin for locking the guide means P1 relative to the main body 10 when aligned with the desired locking hole 14.

The crane arm 1 has an actuator 30 operable to vary the length of the cable 25 in use, and thereby vary the suspended extent L of the lifting wire from the crane arm 1.

The actuator 30 in this example is a winch 30a. The cable 25 has a first end 251 connected to the winch 30a, fixedly to the winch drum. The second end 252 is connected fixedly to an element of the main body 10. The cable 25 from the winch 30a is routed to a supporting element P2 near the second end 102 of the arm, the support element P2 including an idler wheel. The cable 25 is routed onward to the guide means P1, passes over the idler of the guide means P1 around the hook idler wheel P9 in the outboard loop 44 and back to the guide means, passes over an idler of the guid means P1 and onward to the further support element P3 of the main body 10 near the first end 101 of the crane arm, the support element P3 also including an idler wheel. From the support element P3, the cable 25 then passes around the idler wheel of support element P3 and back toward the second end 102 to be connected fixedly to an element of the main body 10 near the second end 102.

The manner of routing of the cable 25 reducing the resultant force against the guide means P1 under load, the guide means P1 may be urged along the longitudinal axis X1 with minimal force. Also, it may allow the guide means P1 to be unlocked, e.g. manually, from locking holes 14 and moved along the longitudinal axis X1 whilst under load and an object is suspended upon and/or being lifted or lowered on the cable 25.

The crane has carrying handle 12 on an upper side of the main body 10. This may conveniently allow the user to grip onto the crane arm, lift and carry, e.g. for relocation and use somewhere else. In other variants, other gripping portions or aids for manually lifting and carrying the arm may be provided. In one such variant a pad may be provided with cushioning or protection for comfortably resting the crane on a person's shoulder for transporting the crane arm to another location. The pad may be provided in addition to the handle and can for example be added on an underside of the main body 10 in the example of Figure 1.

The winch 30 is connected to a transmission 35 for driving the winch. The transmission 35 may be driven by an energy source (not shown). In some variants, the energy source is integrated in the crane arm 1 and includes a battery. The energy source in other examples is externally connected to the crane arm 1. The energy source is in various examples any of a drill, a battery or stationary power.

In Figure 2 the crane arm 1 is similar to Figure 1 except that the actuator 30 is a linear actuator 30b. The linear actuator 30a extends along the crane arm between the first end portion 101 and the second end portion 102 and includes a screw rod 32. The screw rod 32 has a first end 321 which is connected to the transmission 35 (near the first end 101 of the crane arm) and a second end 322 which is a free end located near the second end 102 of the crane arm 1. Tension in the cable 25 keeps the screw rod 32 in-line with the idler of the support element P2. The second end 322 of the rod in other variants (not shown) is supported laterally with respect to the main body 10.

A yet further support element P4 is connected to the screw 32. The support element P4 includes an idler around which an inboard portion of the lifting cable 25 passes. When the screw rod 32 rotates about its long axis, as indicated by arrow IR, the yet further support element P4 will move toward the first end 321 or the second end 322 of the rod 32 depending upon the direction of rotation. Accordingly, the support element P4 is movable along the rod 32 toward or away from support element P2/first end 102 of the crane arm 1. The length of the cable 25 between the support elements P2 and P4 is thus varied. The suspended extent of the length of the cable 25 in the loop 44 from the guide means P1 is varied accordingly.

The inboard portion of the cable 25 may loop around and/or between the idler wheels of support elements P2 and P4 several times, to facilitate providing a higher pulling force for lifting greater loads on the cable 25.

Using the "pulley principle" low force can thus be used to pull high loads. In the example using the linear 30b actuator, the lifting cable 25 is not coiled onto a drum to adapt the length of the cable and the full routing and sufficient suspension length of the cable 25 is accommodated by manipulation merely from the linear actuator 30b. The screw rod 32 may thus transfer a large pulling force, meaning that a low input force to the transmission 35 can allow heavy loads to be lifted.

The extent of the inboard portion 21 of the cable 25 and the outboard portion 22 of the cable 25 changes during a hoist operation. When for instance the hook idler wheel P9 is lowered during a hoisting operation, the inboard length 21 decreases whilst the outside length 22 increases, and vice versa.

The outboard length 22 is at its longest and the inboard length 21 is at its shortest when the hook idler P9 is at its farthest from the guide means P1.

The inboard length 21 is at its longest and the outboard length is at its shortest 22 when the hook idler P9 is at its nearest possible position to the guide means P1. When the inboard length 21 is at its longest, almost the entire wire is accommodated inside the crane arm 1.

In Figure 3, the crane arm 1 has a first actuator 30 in the form of a winch 30a for adjusting suspended extent L of the outboard portion of the cable and a second actuator 40 for moving the guide means P1 longitudinally. In this example, the guide means P1 is movable by an actuator 40 which is a second linear actuator 40b having a screw rod 42. By rotating the screw rod 42 the guide means P1, having a member arranged to engage with the thread of the screw rod 42, is moved along the longitudinal axis X1. The second linear actuator 40 is in this example operated by an electric motor 45. In other variants, the second linear actuator 40 is manually operated, for example a handle is turned to rotate the screw rod 42.

The guide means P1 in this example is supported to travel along the main body 10 on a rail. The guide means may be arranged to be supported in bearing relationship upon the rail 46, e.g. via bearings or low friction surface contact. The guide means P1 is therefore slidable or rollable along the rail 46 in the longitudinal direction when driven by the actuator 40.

In Figure 4, the first actuator 30 is a linear actuator 30b and the second actuator 40 for moving the guide means P1 is a linear actuator 40b. The first linear actuator 30b and the second linear actuator 40b are operated separately.

In a variant of Figure 4, the first linear actuator 30b and the second actuator 40b may comprise motors being controlled by a control unit, so that the two actuators 30b, 40b can synchronize their movements. The control unit may be programmable so that the position of the guide means P1 and the support element P4 can automatically adjusted, for instance if the crane arm 1 is used for repeated operations.

Figure 5 depicts the guide means P1 having a first idler track 62 for the portion of 25a of the cable toward the first end support element P3, rearward of the guide means P1, and a second idler track for the portion 25b of the cable toward the second end support element P2, forward of the guide means P1.

Figure 6 depicts the support element P2 having first and second idler tracks 72 for facilitating multiple windings of the lifting cable 25 around the support element P2 (in combination with the support element P4 for example) for enhanced torque to load lifting ratios.

With reference to Figure 7 there is depicted generally a small workspace 100 with a ceiling 102. The crane arm 1 is coupled to the ceiling 102 to which a base element 7 is attached fixedly in various configurations A to D. The inset configuration E indicates a configuration for coupling the crane arm to a beam 103 with the base element 7 adapted accordingly to fit the beam 103. The crane arm is quick coupled to the base element 7 and is rotatable at or near its coupling end about a vertical axis relative to the base element 7. This can be an overhead beam, although it can similarly be attached to any convenient beam.

In Figure 8, a workspace 200 is depicted with a wall 208 and a floor 209. The crane arm 1 is coupled to the wall 208 to which a base element 7 is attached in various configurations F to H. The configuration I indicates a configuration for coupling the crane arm 1 to a beam 203 which in turn is supported on a fixed floor post 204. The crane arm 1 is quick coupled to the base element 7 and is rotatable at or near its coupling end about a vertical axis relative to the base element 7.

In Figure 9, a workspace 300 is depicted with a wall 308 and floor 309. The crane arm 1 is coupled in configurations J to M to various mobile supporting structures comprising stands 319 standing on the floor 309 and which can be easily moved to other positions upon the floor 309, e.g. on wheels or by lifting and placing them somewhere else. The crane arm 1 is coupled to the base element 7 on the stends 319. The crane arm 1 is quick coupled to the base element 7 and is rotatable at or near its coupling end about a vertical axis relative to the base element 7. The configuration J has two arms mounted on two parts of the stand 31.

Figures 10A to 10C show generally a sequence of quick-coupling the crane arm 1 to a supporting structure in the form of a quick connect bracket 407 fastened to the wall 408. The relationships can be further understood with reference also to Figures 11 and 12. The crane arm 1 is supported on the bracket 407 in stowed configuration in Figure 10A, extending vertically along the wall 408. The crane arm has a hook member 82 arranged to hook onto a corresponding lip 81 on the bracket 407. In this stowed configuration, the hook member 82 engages the lip 81 so that the crane harm hangs from the bracket from the hook 82 in engagement with the lip 81. The hook member 82 can engage the lip 81 by manually placing the crane arm appropriately to guide the hook onto the lip. The crane arm 1 is pivoted on the lip 81 as indicated in Figure 10B in direction P about horizontal axis S toward a use configuration. This brings the end 101 of the crane arm 1 into proximity to the bracket 407 for connection thereto. In Figure 10C the crane arm is quick coupled to the bracket. The end portion 101 of the arm has an upper and lower connecting pins 51, 52 which engage with hole formations 157a, 157b in the bracket 407 for receiving the connecting pins 52, 52. The upper pin is spring and retracted upon locating the end portion 101 of the arm 1 into coupling position with respect to the bracket 407. The upper pin when in position releases and is urged, typically by spring bias into the hole formation 157, connecting the arm to the bracket 407. Figure 12 indicates the movement T horizontally from a not yet connected position 91 of the pin 51 to a connected position 92.

In Figure 13, the quick coupling 50 has a lower pin 51 and an upper pin 52 for coupling the crane arm 1 to the base element 7. The upper and lower pins 51, 52 are spring loaded by a vertical spring 53. The spring 53 biases the upper toward the upper formation 157a, typically a pin receiver hole, of the base element 7. A lock wire 55 is connected to the upper pin 52 to release the upper pin 52 from the base element 7. The upper pin 52 is retracted into the crane arm 1 by pulling the pin out of the upper formation 157a in the base element 7 for disconnecting the near end 101 of the crane arm from the base element. The upper pin 52 may be similarly retracted by pulling the wire 55 to allow insertion of the near end 101 of the crane into the connecting position for connecting the crane arm 1 to the base element.

In some variants, the quick coupling 50 includes a rotation lock member arranged to engage with the upper pin 52 or the lower pin 51 for preventing rotation of the crane arm with respect to the base element 7, if and where necessary.

In Figures 14A to 14A and 15 a crane arm 501 is depicted with an alternative quick connect/ disconnect coupling for connecting the crane arm 501 to the supporting structure 508. The crane arm 501 is constructed otherwise as for crane arm 1 above. In this example, the crane arm 501 has an upper pin 551 which engages in an upper hole 557 through an upper member of the bracket 507 retaining the arm in place in the use position (Figure 14C).

The crane arm 501 has a hook member 582 for hooking into and engaging pivotably a lower hole 597 through a lower member of the bracket. The hook member 582 in the lower hole 597 positions the crane arm 501 laterally on the bracket and supports the crane arm 501 on the bracket 507 on an edge of the hole 597 during movement and transition pivotably (see Figure 14B) from the stowed position (Figure 14A) to the use position (Figure 14C).

Claims

CLAIMS1. A crane arm comprising a quick connect/disconnect member for quick-connecting the crane arm to a supporting structure or quick-disconnecting the crane arm from the supporting structure.
2. A crane arm as claimed in claim 1, configured to be carried manually once removed from the supporting structure.
3. A crane arm as claimed in claim 1 or 2, further comprising any of: at least one grip portion; at least one strap; at least one carry handle or other means for carrying and/or relocating the crane arm.
4. A crane arm as claimed in any preceding claim, wherein quick connect/disconnect member comprises a pivot member for supporting the crane arm upon the supporting structure and pivoting the crane arm from a stowed position to a use position.
5. A crane arm as claimed in any preceding claim, further comprising: guide means from which a lifting line is suspendable in a loop from the crane arm, the guide means being movable in along the crane arm for obtaining a desired position of suspension of the lifting line; the guide means being configured to guide first and second sections of the looped line through the guide means, so that a rearward component of force is imparted to the guide means by one of the first and second sections of line and a forward component of force is imparted to the guide means by the other of the first and second sections of line.
6. A crane arm as claimed in claim 5, including the lifting line, wherein the first section of the line extends through the guide means from a region rearward along the crane arm with respect to the guide means and the second section of the line extends through the guide means toward a region forward along the crane arm with respect to the guide means.
7. A crane arm as claimed in claim 5 or 6, wherein the guide means comprises a cross-over for the first and second sections of line.
8. A crane arm as claimed in any of claims 5 to 7, including an actuator operable for moving the guide means longitudinally along crane arm.
9. A crane arm as claimed in claim 8, wherein the actuator comprises a linear actuator comprising a screw rod which is rotatable to move the guide means longitudinally.
10. A crane arm as claimed in any preceding claim, further comprising at least one support element that is movable along the crane arm for varying the suspended extent of a lifting line from the crane arm in a direction transverse to the longitudinal direction
11. A crane arm as claimed in claim 10, wherein the support element is positioned near the second end of the crane arm.
12. A crane arm as claimed in claim 10 or 11, having at least one actuator operable to produce the movement of the support element along the arm.
13. A crane arm as claimed in claim 12, wherein the actuator is a linear actuator.
14. A crane arm as claimed in claim 13, wherein the linear actuator comprises an actuator rod extending along the crane arm, the actuator rod being operable to produce movement of the support element.
15. A crane arm as claimed in claim 14, wherein the actuator rod is a threaded screw rod which is rotatable about its longitudinal axis to produce movement of the support element toward or away from the second end of the crane arm, the lifting line supported around the support element.
16. A crane arm as claimed in any preceding claim, including control electronics for operating one or more actuators or other devices for performing any of: moving a load suspended on a lifting line of the crane along the crane arm; raising or lowering the load on the lifting line; positioning the crane; or locking the crane in a use position; and the control electronics being configured to receive control signals wirelessly from a remote transmitter.
17. A crane arm as claimed in any preceding claim, including a detachable battery for supplying electrical energy.
18. A crane arm comprising: guide means from which a lifting line is suspendable in a loop from the crane arm, the guide means being movable along the crane arm for obtaining a desired position of suspension of the lifting line; the guide means being configured to guide first and second sections of the looped line through the guide means, so that a rearward component of force is imparted to the guide means by one of the first and second sections of line and a forward component of force is imparted to the guide means by the other of the first and second sections of line.
19. A crane arm as claimed in claim 18, wherein the lifting line is not stored on a drum.
20. A crane arm comprising: at least one support element that is movable in a longitudinal direction along the crane arm for varying the suspended extent of the lifting line from the crane arm in a direction transverse to the longitudinal direction.
21. A system comprising. a supporting structure, and the crane arm as claimed in any preceding claim configured to be coupled to the supporting structure.