WO1998047808A1

WO1998047808A1 - Lifting apparatus

Info

Publication number: WO1998047808A1
Application number: PCT/AU1998/000297
Authority: WO
Inventors: Bruce Rodney Best
Original assignee: Bruce Rodney Best
Priority date: 1997-04-23
Filing date: 1998-04-23
Publication date: 1998-10-29
Also published as: AUPO635097A0

Abstract

A lightweight, portable and demountable crane comprises a substantially rigid framework (1, 3, 4, 5 and 11) which may be erected on an elevated platform. A lifting device (14, 15, 16) is movably mounted on the framework and is operable to move load (18) vertically. The lifting device (14, 15, 16) is also movable or rotatable with respect to the framework to transport load (18) horizontally across the platform and through an adjacent doorway. A stabilising strut (12) is connected to the framework at (8) and is held between two fixed structural components such as the doorsill and lintel to hold the crane in position on the platform and to counterbalance the load when the crane is lifting or transporting the load. A bridge crane is also disclosed.

Description

LIFTING APPARATUS

Field of Invention

The invention relates to apparatus for lifting a heavy and/or bulky load, particularly to lifting apparatus which is capable of being used in a confined area. The invention is primarily concerned with the delivery of heavy and/or bulky goods to the upper levels of a multi-level building.

Description of Prior Art

Increasing urban densities and changes in living patterns have resulted in a significant increase in the amount of multi-level buildings used for living and office purposes. This, combined with restricted access to such buildings, has presented the building, removals and other industries with problems relating to the delivery of heavy and/or bulky goods such as furniture, pianos, whitegoods appliances and office equipment. There has often been difficulty in delivering heavy and/or bulky goods to above ground levels of a multistorey building not provided with a lift or elevator of adequate size. If delivery was made via a stairway, particularly a narrow stairway of several flights and corners, a plurality of handlers has normally been required. Labour has at least in recent times been expensive. In addition, there has always been a risk of damage to both the goods and the building. Sometimes, dismantling of the goods has been required with a consequent reassembly on site If delivery was made via an elevated balcony or window, expensive ground based materials handling elevating equipment has had to be employed. Although the use of such equipment may be justified during the construction phase of the building,, to hire such equipment to deliver a single consignment of goods has proved costly. Similar problems exist where heavy and/or bulky goods have had to be transferred from an above ground level of a multi-storey building. Difficulties have often been encountered in other situations, even within a building or outdoors, where heavy and/or bulky goods needed to be moved from one level to another, particularly where the movement of goods has been a one-off exercise.

Description of the Invention

It is an object of the invention to provide apparatus which would simplify the raising or lowering of goods in the circumstances described.

It is another object of the invention to provide apparatus which is not only capable of lifting a load in a vertical direction but also capable of transporting the load in a horizontal direction.

It is also an object of the invention to provide lightweight, portable and demountable lifting apparatus which is simple to operate by one person.

It is a further object of the invention to provide apparatus which is capable of being used to deliver a range of heavy and/or bulky goods to an upper level of a multi-storey building via a balcony or a large window area in a safe, non-intrusive, efficient and cost effective manner.

It is proposed to provide a lightweight, portable and demountable lifting apparatus in the form of a crane. The crane is lightweight and portable and in its disassembled state it may be carried by one or two persons or on a small trolley to the site where it is intended to be used. The crane may then be erected on a lifting platform which may be any elevated level area such as the floor of a balcony of a unit in a multi-level building or a floor within a unit adjacent an open window. The crane is demounable and may be quickly and easily assembled and disassembled in a confined space. After being disassembled it may be conveniently removed from one site and reassembled at a new location. It is also proposed to provide means to stabilise the crane when under load. In use, the stabilising means is connected to the framework and is held between two fixed structural components on or adjacent to the lifting platform. For example, when the crane is erected on a unit balcony adjacent an open doorway, the stabilising means may be held between the doorsill and the lintel.

In accordance with the invention, a lightweight, portable and demountable crane comprises a substantially rigid framework adapted to be erected on a lifting platform, a lifting device movably mounted on said framework, said lifting device being operable to move a load in a substantially vertical direction, said lifting device also being movable with respect to the framework to transport said load in a substantially horizontal direction and a stabilising strut connected to the framework and adapted to be held between two fixed structural components on or adjacent to the lifting platform to hold the crane in position on the platform and to counterbalance the load when the crane is lifting or transporting the load.

Brief Description of the Drawings

In the drawings:

Fig. 1 is a schematic illustration of one embodiment of the invention wherein the lifting apparatus is in the form of a cantilever crane erected on the balcony of a unit in a multi- level building;

Fig. 2 is a front view (from off the balcony) of the cantilever crane schematically illustrated in Fig. 1 but including more constructional details;

Fig. 3 is a side view of the cantilever crane schematically illustrated in Fig. 1 but including more constructional details; Fig. 4 is a front view of a part of the cantilever crane in a collapsed condition suitable for transport; and

Fig. 5 is a schematic illustration of a second embodiment of the invention wherein the lifting apparatus is in the form of a bridge crane.

Description of Embodiments

In the embodiment of the invention schematically illustrated in Fig. 1, the lifting apparatus is in the form of a cantilever crane. The crane may comprise a demountable supporting frame carrying a boom pivotally mounted so as to be capable of rotation about a substantially vertical axis. The boom may be equipped with hoisting tackle extending from a winch, mounted adjacent one end of the boom, and extending along the boom to extend over its other end for connection to the load to be lifted. When the load is lifted to the desired height, the boom may be pivoted to move the load horizontally. The crane is provided with stablising means to hold it in position while lifting or moving the load.

The crane illustrated in Fig. 1 is shown as having been erected on an elevated balcony or platform adjacent to a doorway opening and is positioned to lift heavy and/or bulky goods from ground level and transfer them through the doorway opening. The crane in its disassembled condition may be carried to the balcony and assembled by one or two persons.

In its assembled condition, the crane comprises a demountable supporting frame having a substantially vertical, strong central post 1 which constitutes the principal load bearing member of the frame. Post 1 is preferably of tubular steel or similar material of square cross-section, although other cross-sections may be used. The lower end of post 1 fits removably within and mates with a cup-shaped socket (not shown) fixed to the upper side of foot-plate 2. The frame also includes supporting struts 3, 4 and 5 which, at the upper end thereof, are releasably or movably secured adjacent the top end of central post 1 in any suitable manner. The lower end of each strut 3, 4 and 5 fits removably within and mates with a cup-shaped socket (not shown) fixed to the upper side of footplates 6, 7 and 8, respectively. Preferably, each foot-plate 2, 6, 7 and 8 comprises a metal plate having fixed on its lower side a layer of rubber or the like for non-slip purposes. No drilling or other special mounting means is required. Preferably, the cup-shaped sockets are also of metal and are fixed to the upper sides of the foot-plates by, say, welding. It is not necessary to provide any special retaining means to hold the lower ends of post 1 and of struts 3, 4 and 5 in the corresponding cup-shaped sockets. With a friction fit, the weight of the crane, especially under load, is sufficient.

To maintain the frame in an erected position, central post 1 is connected to struts 3 and 4, for example, by detachable stay wires 9 and 10, respectively. To stop struts 3 and 4 from spreading with respect to central post 1, other bracing means could be employed such as struts detachably secured to central post 1 and struts 3 and 4, respectively. In addition, a bracing strut 11 is detachably secured to foot-plates 2 and 8. For example, the ends of bracing strut 11 could be held in mating sockets fixed to foot-plates 2 and 8, respectively, by any suitable means such as spring clips. It is important that strut 11 is secured to both foot-plates 2 and 8 because strut 11 may be subject to tension or to compression depending upon the position of the load carried by the crane as it is lifted and then swung across the balcony.

Preferably, strut 3 and stay wire 9 are shorter than strut 4 and stay wire 10, respectively. These members may be interchanged so that the crane may be located at the best position on the balcony having regard to the doorway and the manner in which the door opens. Means are provided to stabilise the crane, particularly when under load and when transferring a load in a horizontal direction. The framework includes a stabilising strut 12. In addition to being connected to part of the framework, strut 12, when the crane is in use, extends between rigid parts of the building. In the illustrated embodiment, stabilising strut 12 is shown extending between the doorsill and the lintel. Other parts of the building may be used. For example, the stabilising strut could extend between the upper surface of one balcony and the under surface of the balcony immediately above it. Again, the stabilising strut 12 could extend between the upper surface of the floor and the under surface of the concrete floor immediately above it. The lower end of stabilising strut 12 fits removably within and mates with a cup-shaped socket (not shown) fixed to the upper side of foot- plate 8. The upper end of stabilising strut 12 fits removably in and mates with a cup-shaped socket (not shown) fixed to the under side of plate 13, the other side of which rests against the lintel, preferably with an intermediate layer of rubber or the like for non-slip purposes A screw jack (not shown) is provided within the length of strut 12 so that, after being assembled loosley in position, the length of strut 12 can be increased by means of the screw jack to force plates 8 and 13 against the doorsill and lintel, respectively. Alternatively, the screw jack may be incorporated with footplate 8.. In some circumstances it may be necessary to position counterweights on foot-plate 8 to assist stabilisation of the crane.

A boom 14 is mounted at the top of post 1 for, preferably limited, rotation about the longitudinal axis of post 1. The boom 14 carries a powered or manual winch 15 adjacent one end thereof to control lifting wire or tackle 16 passing over a pulley 17 at the other end of boom 14. By operation of winch 15, lifting tackle 16 may be wound in to raise the load 18 to above the height of the balcony railing (not shown). The boom 14 is then swung about the longitudinal axis of post 1 to transfer load 18 horizontally over the railing and the longer strut 4 and through the doorway. If desired, a load limiter may be employed to restrict the load that can be carried by the winch 15.

Fig. 2 to 4 show more constructional details of the cantilever crane illustrated schematically in Fig. l. Central post 1 and struts 3, 4, 5, 11 and 12 are each made of tubular steel of square cross-section. For ease of carrying and to permit the length of the struts to be adjusted, struts 3, 4, 5, 11 and 12 are formed in sections with one section of a strut telescopically fitting within another. In the erected condition of the crane, the sections of a strut may be held together by any suitable means, for example by spring clips passing through matching holes 26 in each section. A series of holes is provided in 0 each section so that the length of the struts may be adjusted. Instead of stay wires 9 and 10, the lower ends of central post 1 is connected to the lower ends of struts 3 and 4 by bracing struts 19 and 20, respectively. Bracing strut 19 is pivotally connected at 24 to strut 3 and releasably connected to central post 1. Bracing strut 20 comprises two members pivotally connected together at adjacent ends to form a scissors lock and 5 pivotally connected to the lower parts of central post 1 and strut 4 at the other ends thereof. Near to the top thereof, central post 1 has connected thereto, as by welding, three downwardly inclined, metal channel- shaped members 21, 22 and 23. As shown in Figs. 2 and 3, one channel shaped member is connected to each of three sides of central post 1. The lower sides of channel members 21, 22 and 23 are open. The top ends of

20 struts 3, 4 and 5 fit within channel-shaped members 21, 22 and 23, respectively, and are pivotally connected thereto at 24. Channel-shaped members 21 and 22 are provided with holes 25 which mate with holes in struts 3 and 4. Spring clips are inserted through mating holes to maintain the crane in its erected position.

Adjacent the top of central post 1, on the remaining or free side thereof, a metallic socket 25 27 is connected to central post 1 as by welding. Although socket 27 has a square cross- section, it is formed with a bore of circular cross-section which receives a circular axle supporting boom 14. Co-operating stops (not shown) are provided on the boom support and the socket 27 to restrict the rotation of boom 14 around the axis of socket 27 and ensure that boom 14 always passes over the longer strut 4. The boom may be formed of telescopic sections which are provided with mating holes 26 for the reception of a spring clip.

To disassemble the crane, boom 14 is reduced to its shortest length and the axle of the boom support removed from socket 27. Stabilising strut 12 and bracing strut may then be disconnected. After removing the spring clips from mating holes 25 and 26, struts 3, 4 and 5 may be folded against central post 1 as shown in Fig. 4. The detached parts of the crane may be assembled into a package which could be carried or mounted on a small trolley.

The lifting apparatus may take other forms than the cantilever crane described above. For example, as illustrated in Fig. 5, a bridge crane may be employed, particularly where the goods have to be lifted to an upper level of a high rise building. In this case, a demountable framework is employed to support two spaced horizontal tracks or rails 31 projecting outwardly from a door or window opening. The demountable framework comprises a plurality of stabilising struts 35 which, at the lower ends thereof, are supported by the internal floor 38 of the unit. At the upper end thereof, struts 35 press against the underside 36 of the floor above. A screw jack (not shown) is incorporated within the length of each strut 35 to enable the length of struts 35 to be increased so that the ends thereof press firmly against floor 38 and the underside 36 of the floor above and so form a rigid framework. Tracks 31 are rigidly supported near to the top of stabilising struts 35. Other supporting struts such as 37 may be employed. A gantry 32 spans the space between tracks 31 and rides thereon. Supported on gantry 32, is a winch 33 which may be connected by a cable to load 34. When the crane is assembled, gantry 32 may be caused to run horizontally on rails 31 to a position outside of the building. Load 34 is connected to the cable and winch 33 is operated to lift load 34 vertically to above the level of floor 38. Gantry 32 is retracted in a horizontal direction along rails 31 to bring load 34 within the building. The winch may be further operated to lower load 34 onto floor 38.

Other types of lifting apparatus may be employed and other modifications included within the scope of the invention herein described.

Claims

1. A lightweight, portable and demountable crane comprises a substantially rigid framework adapted to be erected on a lifting platform, a lifting device movably mounted on said framework, said lifting device being operable to move a load in a substantially vertical direction, said lifting device also being movable with respect to the framework to transport said load in a substantially horizontal direction and a stabilising strut connected to the framework and adapted to be held between two fixed structural components on or adjacent to the lifting platform to hold the crane in position on the platform and to counterbalance the load when the crane is lifting or transporting the load.

2. A crane as claimed in Claim 1, wherein the rigid framework comprises a vertical central post and a plurality of supporting struts.

3. A crane as claimed in Claim 2, wherein a boom is mounted at the top of the central post for rotation about a substantially vertical axis, said lifting device being mounted on said boom.

4. A crane as claimed in Claim 2, wherein the lengths of the struts are adjustable.

5. A crane as claimed in Claim 1, wherein the rigid framework comprises a plurality of vertical stabilising struts.

6. A crane as claimed in Claim 5, wherein two horizontal rails are supported by the stabilising struts and a gantry is movably supported on the rails, said lifting device being mounted on said gantry.

7. A crane as claimed in Claim 1, wherein the lifting device comprises a winch from which a cable is fed for connection to the load.

8. A crane as claimed in Claim 5, wherein the length of each stabilising strut is adjustable.