GB2595254A

GB2595254A - Lifting assembly

Info

Publication number: GB2595254A
Application number: GB2007408.4A
Authority: GB
Inventors: Miller Bruce
Original assignee: Terlok Ltd
Current assignee: Terlok Ltd
Priority date: 2020-05-19
Filing date: 2020-05-19
Publication date: 2021-11-24
Anticipated expiration: 2040-05-19
Also published as: GB202007408D0; GB2595254B

Abstract

A pulley 20 has a main body 22 with a channel 38 for receiving a length of threaded rod 14a, b where the channel has a deformable lining 46, which may be an elastomer. The main body is moveable between open configuration in which a length of threaded rod is insertable into the channel and a closed configuration in which the channel grips the threaded rod by deformation of the lining. A locking member (56 fig.6) secures the main body in the closed configuration. The pulley may form part of a lifting device 12 for lifting a load 2 such as an air conditioning unit (ACU) that has two pulleys on a support bar 84 with a fixed pulley mechanism 86 with ropes 4 which also pass through a sheave 30. The pulley may have a cam cleat 74 to restrain the rope on lifting. The lifting assembly may also have a support board or lifting beam 128 attached to a sling 16. The fixed pulley may have a swivel 120 so the load can be rotated into position prior to suspending from the threaded rods.

Description

Lifting Assembly

FIELD OF THE INVENTION

The present invention relates to a pulley, a lifting device including a pulley and a lifting assembly. The present invention also relates to the use of the pulley, the lifting device and the lifting assembly to lift or raise a load. In some embodiments the invention relates to a lifting assembly providing a rope and pulley system that may be secured to threaded rods and used to lift a bulky item. The lifting assembly may be used to raise an air conditioning indoor fan-coil unit into a ceiling cavity.

BACKGROUND TO THE INVENTION

One type of air conditioning unit is an indoor fan-coil unit, which may be a ceiling cassette air conditioning unit. These are typically mounted in an opening in a suspended ceiling such that the majority of the unit is located above the ceiling and, after installation, the only visible part is a lower face of the unit.

A traditional ceiling air conditioning (AC) fan-coil unit comprises a cabinet or housing surrounding the working parts of the unit, and a visible cover or face plate. In many known systems the face plate has a square perimeter, while the cabinet or housing (which locates above the suspended ceiling and is not visible in use) may be of any suitable shape. It will be appreciated that external dimensions of the cabinet, in a plane parallel to the face plate, are smaller than external dimensions of the face plate, so that the fan-coil unit may be installed in an opening in a ceiling as described further below.

Many known AC fan-coil units are suspended from lengths of threaded rod or stud secured to the ceiling structure above the suspended ceiling. Typically an AC fan-coil unit will be suspended from four studs, each disposed proximate one of the corners of the unit. -2 -

Typical external dimensions of these units may be approximately 900 mm x 900 mm x 300 mm. As such, although these air conditioning fan-coil units are not very heavy, they are bulky.

Installation in a ceiling traditionally involves the following steps: if required, creating an opening in a suspended ceiling in the desired location (in a new build the ceiling may be installed after the air conditioning units); installing threaded rods or studs in a ceiling space in the required locations for connection to the unit; raising the housing of the air conditioning fan-coil unit towards the studs; supporting the housing whilst the housing is secured to the studs; and attaching the face plate to the housing.

Traditionally installation of an AC fan-coil unit requires at least two people. These installers will typically work at height on a pair of ladders positioned below the ceiling opening. The two installers will lift the unit into the opening, and then both of the installers need to support the weight of the unit, while they secure each side of the unit to the studs.

It will be appreciated that this makes installation of these units a potential health and safety issue, time consuming and costly, as at least two people are required to undertake each installation.

In some circumstances it may be possible to utilise a pneumatic lift, such as a pneumatic scissor lift. Such a lift may be used to support and raise an AC fan-coil unit into an opening in a ceiling; however, two installers are still needed to secure the unit to the studs. Furthermore, the locations in which this is possible are limited. Pneumatic scissor lifts are themselves bulky and heavy, and as such their use on project installations is limited and awkward.

Against this background it is desirable to provide a safer alternative and improved lifting device or hoist for raising a load such as an air conditioning unit during -3 -installation. In particular, it is desirable to provide a suitable hoist that can be operated by a single user, so that one person can install an air conditioning unit if needed.

SUMMARY OF THE INVENTION

A first aspect of the present invention provides a pulley comprising: a main body including a channel for receiving a length of threaded rod, the channel having a deformable lining, and the main body being moveable between an open configuration in which a length of threaded rod is insertable into the channel and a closed configuration in which, in use, the channel grips said length of threaded rod by deformation of the lining; a locking member arranged to secure the main body in the closed configuration; and a sheave.

In preferred embodiments the pulley is configured such that, in the open configuration, a length of threaded rod is insertable into the channel in a direction perpendicular to an axis of the channel.

The main body preferably comprises a first clamping portion and a second clamping portion, each of the first and second clamping portions including a part of the channel and the first and second clamping portions being hingedly connected to each other to permit the second clamping portion to move with respect to the first clamping portion between the open and closed configurations.

The sheave may mounted on a support bracket extending from the main body.

In some embodiments the pulley further comprises a cam cleat.

A second aspect of the invention provides a pulley according to the first aspect of the invention and in which the main body further comprises a passage for receiving -4 -a support bar, an axis of the passage extending substantially perpendicular to an axis of the channel. Preferably a rotational axis of the sheave is perpendicular to each of the axis of the passage and the axis of the channel.

A third aspect of the invention provides a lifting device comprising: a first pulley according to the second aspect of the invention; a second pulley according to the second aspect of the invention; and an elongate support bar extending through the passage in the first pulley and through the passage in the second pulley, such that the first pulley is spaced from the second pulley and a central section of the support bar extends between the first pulley and the second pulley.

A fourth aspect of the invention provides a lifting device according to the third aspect of the invention and further comprising: a fixed pulley engaged with the central section of the support bar, the fixed pulley comprising a carriage including a passage through which the support bar extends and a sheave; means for preventing sliding of the first pulley along the support bar in a first direction; and means for preventing sliding of the fixed pulley along the support bar in a second direction, the second direction being opposite the first direction.

The fixed pulley preferably comprises two sheaves, the sheaves being spaced apart in a direction parallel to an axis of the support bar. In preferred embodiments a rotational axis of the or each sheave of the fixed pulley is perpendicular to an axis of the support bar.

A fifth aspect of the invention provides a lifting device according to the fourth aspect of the invention and further comprising a lifting pulley including a mount for attachment to a load to be lifted by the lifting device and a sheave. The lifting pulley preferably comprises two sheaves having a common rotational axis. The mount may comprise a swivel. -5 -

A sixth aspect of the invention provides a lifting device according to the fifth aspect of the invention and further comprising a sling for supporting a load to be lifted by the lifting device, the sling comprising at least one strap, and the sling being connected to the mount of the lifting pulley. In preferred embodiments the sling comprises a spreader board connected to the mount of the lifting pulley, and the strap is connected to and extends from the spreader board. In other embodiments the sling comprises a lifting beam connected to the mount of the lifting pulley, and the strap is engaged with the lifting beam.

In some embodiments a lifting device according to one of the third, fourth, fifth or sixth aspects of the invention further comprises an elongate length of rope engaged with the or each sheave.

A seventh aspect of the present invention provides a lifting assembly comprising: a lifting device according to one of the third, fourth, fifth or sixth aspects of the invention; a first threaded rod; and a second threaded rod, wherein, the first pulley is engaged with the first threaded rod and the second pulley is engaged with the second threaded rod.

In preferred embodiments of the lifting assembly a load to be lifted is secured in the sling.

In some embodiments of the lifting assembly the load to be lifted is an air conditioning fan-coil unit, such as a ceiling cassette air conditioning unit.

An eighth aspect of the present invention provides a method of lifting a load using a pulley comprising: inserting a length of threaded rod into a channel of a main body of the pulley with the main body in an open configuration;

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clamping the threaded rod in the channel by moving the main body into a closed configuration in which a deformable lining of the channel grips the threaded rod; - engaging a locking member to secure the main body in the closed 5 configuration; engaging a length of rope with a sheave of the pulley; connecting a first part of the length of rope on a first side of the sheave to the load to be lifted; and - applying a force to a second part of the length of rope on a second side of the sheave so as to lift the load.

In preferred embodiments of the method the threaded rod is inserted into the channel in a direction substantially perpendicular to a longitudinal axis of the channel.

A ninth aspect of the present invention provides a method of using a lifting device according to the fourth aspect of the invention comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; - engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; - clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheave of the fixed pulley and the sheave -7 -of the first pulley; connecting a first end portion of the length of rope to a load to be lifted; and applying a force to a second end portion of the length of rope so as to lift the lift A tenth aspect of the present invention provides a method of using a lifting device according to the fifth aspect of the invention comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; - clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; - engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; attaching the mount of the lifting pulley to a load to be lifted; and applying a force to the second end of the length of rope so as to lift the load. -8 -

An eleventh aspect of the present invention provides a method of using a lifting device according to the sixth aspect of the invention comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley 5 with the main body in an open configuration; - clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; - engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; - securing a load to be lifted in the sling such that the spreader board extends over a part of the load and the strap extends around the load; and applying a force to the second end of the length of rope so as to lift the load.

A twelfth aspect of the present invention provides a method of using a lifting device according to the sixth aspect of the invention comprising the steps of:

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inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; - engaging a first locking member to secure the main body of the first pulley in the closed configuration; - inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; - securing a load to be lifted in the sling such that the lifting beam extends over a part of the load and the strap extends around the load; and applying a force to the second end of the length of rope so as to lift the load.

Preferred and/or optional features of each aspect and embodiment described above may also be used, alone or in appropriate combination, in the other aspects and 30 embodiments also.

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BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further described by way of example only and with reference to the accompanying drawings, in which: Figure 1 is a side view of a lifting assembly according to a preferred embodiment of the present invention, the lifting assembly comprising a hoist or lifting device attached to threaded rods and the lifting assembly being used to lift an air conditioning unit in a sling; Figure 2 is a perspective view of a fixed mounting part of the lifting device of Figure 1, including a pair of pulleys and a fixed pulley assembly secured to a support bar; Figure 3 is a further perspective view of the fixed mounting part of the lifting device of Figure 2, Figure 4 is a perspective view of the fixed mounting part of the lifting device of Figure 2 attached to a pair of threaded rods, Figure 5 is a side view of the fixed mounting part of the lifting device of Figure 2; Figure 6 is an exploded drawing showing parts of one of the pulleys of Figure 2; Figure 7 is a perspective view of one of the pulleys of Figure 2; Figure 8 is a further perspective view of the pulley of Figure 7; Figure 9 is a further perspective view of the pulley of Figure 7; Figure 10 is a plan view from above of a part of the pulley of Figure 7; Figure 11 shows perspective views of first and second main body portions of the pulley of Figure 7; Figure 12 is a plan view from above of the first and second main body portions of Figure 11; Figure 13 is a plan view from above of the lifting assembly of Figure 1; Figure 14 is a perspective view of a first embodiment of a support board of the sling of the lifting assembly of Figure 1; Figure 15 is a perspective view of a second embodiment of a support board of the sling of the lifting assembly of Figure 1; Figure 16 is a perspective view of a lifting pulley of the lifting device of Figure 1; Figure 17 is a detailed view of a part of the support board of Figure 14 showing a mount for the lifting pulley of Figure 16; Figure 18 is an exploded drawing showing parts of the lifting pulley of Figure 16; 20 and Figure 19 is a perspective view of a lifting beam forming part of a sling of a lifting assembly according to a further embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A hoist assembly or lifting assembly 10 according to a preferred embodiment of the present invention is shown in Figure 1. The lifting assembly 10 comprises a hoist or lifting device 12 connected to threaded rods 14, and a sling 16 for holding an object 2 to be lifted. In the following description, an embodiment of the lifting assembly 10 is described in which the lifting assembly 10 is configured to support and raise a part of an air conditioning unit 2, and in particular a ceiling cassette air conditioning unit.

-12 -It will be appreciated, however, that the lifting device 12 and the lifting assembly 10 of the present invention may be used to raise any object or load and is not limited to the example of an air conditioning unit described below.

The lifting device 12 of the present invention is configured to clamp to a pair of threaded rods 14, sometimes referred to as studs. These threaded rods 14 may be secured to and extend from a ceiling structure, for example. The lifting device 12 is therefore secured to and supported by the threaded rods 14.

In preferred embodiments the lifting device 12 comprises a rope and pulley system configured to enable an object 2 to be raised or lifted in a direction towards the threaded rods 14. In specific embodiments the object 2 may be lifted towards the threaded rods 14 and then the object 2 may be secured directly to the threaded rods 14. In these embodiments it is envisaged that the lifting device 12 will then be detached from both the object 2 and the threaded rods 14, with the object 2 remaining attached to and supported by the threaded rods 14.

An advantage of the lifting device 12 and the lifting assembly 10 of the present invention is that it may be used by a single user to raise a bulky object single-handedly, which previously may have required at least two users. Furthermore, the lifting device 12 itself is not heavy or difficult to set up, such that it may be used in situations and in environments in which it was not possible or practical to use traditional heavy and bulky lifting equipment.

In its simplest configuration the lifting device 12 of the present invention comprises a single pulley 20. A preferred embodiment of such a pulley 20 is shown most clearly in Figures 6 to 12.

The pulley 20 comprises a main body 22 including a clamping portion 24 and a support portion 26. The clamping portion 24 is configured to clamp around a length of threaded rod 14 to secure the pulley 20 to the threaded rod 14. The support portion 26 of the main body 22 comprises a sheave 30 mounted for rotation about -13 -an axis 32. The clamping force applied to the threaded rod 14 by the clamping portion 24 of the pulley 20 is preferably such that when a force is applied to the support portion 26 of the pulley 20 the pulley 20 does not move with respect to the threaded rod 14.

The clamping portion 24 of the main body 22 preferably comprises a first part or first wing 34 and a second part or second wing 36. The clamping portion 24 further comprises a channel 38 for receiving a part of a length of threaded rod 14. The channel 38 preferably comprises a substantially cylindrical sidewall defining an elongate cylindrical bore. In the illustrated embodiment a first part 40 of the channel 38 is provided in the first wing 34 and a second part 42 of the channel 38 is provided in the second wing 36. In particular, each of the first and second parts 40, 42 of the channel 38 are preferably semi-cylindrical. In this way the channel 38 is split longitudinally between the first and second wings 34, 36.

The first and second wings 34, 36 are moveable with respect to each other between a closed configuration and an open configuration. In the open configuration a length of threaded rod 14 is insertable into the channel 38 and in the closed configuration the sidewall of the channel 38 surrounds the threaded rod 14. As will be discussed further below, it may be advantageous for the clamping portion 24 to be configured such that the threaded rod 14 may be insertable into and removable from the channel 38 in a direction perpendicular to a longitudinal axis 44 of the channel 38. In particular, in the open configuration the channel 38 may be split open, or the first and second parts 40, 42 of the channel 38 separated, to enable a length of threaded rod 14 to be inserted into the channel 38.

The channel 38 preferably includes means to grip or clamp the threaded rod 14 such that when the first and second wings 34, 36 are in the closed configuration the main body 22 is secured to the threaded rod 14 and does not move with respect to the threaded rod 14.

In preferred embodiments the channel 38 comprises a deformable lining 46. The -14 -lining 46 may be made from or comprise a suitable elastomeric material. The lining 46 may be made of rubber. In these embodiments the dimensions of the channel 38 and lining 46 are such that, when the clamping portion 24 of the main body 22 is in the closed configuration, the lining 46 deforms around the thread of the threaded rod 14 thereby gripping the threaded rod 14. In other embodiments the channel 38 may include inwardly projecting protrusions that engage with the thread of the threaded rod 14.

In the illustrated embodiment the first and second wings 34, 36 are connected together by a hinge 48. As shown most clearly in Figures 6 and 11, a first set of knuckles 50 is provided on the first wing 34 and a second set of knuckles 52 is provided on the second wing 36. The first and second set of knuckles 50, 52 are then engaged with each other to form a barrel of the hinge 48 through which a hinge pin 54 extends.

The pulley 20 preferably further comprises a locking member 56 arranged to secure the main body 22 in the closed configuration. As shown most clearly in Figures 6, 8 and 10, in the illustrated embodiment the locking member 56 comprises a lobed knob 58 at a first end of a threaded shaft 60. A second end of the threaded shaft 60 engages in a threaded hole 62 in a spindle 64. The spindle 64 is rotatably mounted in a distal section of the second wing 36 furthest from the hinge 48. In this way, the channel 38, or second part 42 of the channel 38, is disposed between the hinge 48 and the spindle 64. The locking member 56 is rotatable, by rotation of the spindle 64, between a first position in which the lobed knob 58 is not engaged with the first wing 34 and a second position in which the lobed knob 58 is engaged with the first wing 34. In particular, in the first position the lobed knob 58 and threaded shaft 60 are disengaged from the first wing 34 such that the first wing 34 is free to rotate about the hinge 48 with respect to the second wing 36. With the locking member 56 disengaged the first and second wings 34, 36 are, therefore, movable between the open and closed configurations. In the second position the threaded shaft 60 extends through a slot 66 in a distal end of the first wing 34 and the lobed knob 58 is disposed on an opposite side of the first wing 34 to the second wing 36. The -15 -locking member 56 is then rotatable about its axis 68 to screw the threaded shaft 60 through the threaded hole 62 in the spindle 64, and to bring a surface of the lobed knob 58 into contact with a surface of the first wing 34. Further rotation of the locking member 56 about its axis 68 then applies a clamping force to the first wing 34 to press the first wing 34 into engagement with the second wing 36. It will be appreciated that this clamping force also applies a resultant clamping force to a threaded rod 14 disposed in the channel 38 In other embodiments the pulley 20 may include a locking member having a different configuration to the locking member 56 of the present invention. The locking member is, however, arranged to apply a force to one or both parts of the clamping portion to apply a clamping force to a length of threaded rod disposed in the channel.

The sheave 30 is mounted in the support portion 26 such that its rotational axis 32 is perpendicular to the longitudinal axis 44 of the channel 38 in the clamping portion 24. The sheave 30 is in the form of a wheel having a circumferential groove for receiving a length of rope or cord or similar. In this embodiment the sheave 30 is mounted between two plates 70 of a support bracket 72.

In use a rope 4, cord, chain or other elongate flexible member, will be engaged with the sheave 30 such that a part of the rope 4 is seated in the groove. A first end of the rope, on a first side of the sheave 30, is connectable to an object 2 to be lifted. A second end of the rope 4, on a second side of the sheave 30, may then be pulled by a user to raise the object 2.

In preferred embodiments the support portion 26 further includes a cam cleat 74. The cam cleat 74 is preferably secured to a pad of the support bracket 72 and is aligned with the sheave 30. The cam cleat 74 is arranged such that a rope 4 passing over the sheave 30 extends between two cams 76 of the cam cleat 74. The cam cleat 74 allows the rope 4 to be pulled through the cam cleat 74 in a first direction but prevents movement of the rope 4 through the cam cleat 74 in an opposite second direction. In this way a user may pull the rope 4 over the sheave 30 in the first -16 -direction to raise an object 2 secured to the rope 4 and may then release the rope 4. The rope 4 will be prevented from moving back in the second direction by the cam cleat 74 such that the object 2 may be held in a raised position without a user applying a force to the rope 4.

In a preferred embodiment the above-described pulley 20 is combined with other pulleys to form a rope and pulley system having a greater mechanical advantage. In particular, a number of pulleys may be provided to create a rope and pulley system (block and tackle) having two or four rope parts.

As shown in the embodiment of Figure 1, the pulley 20 may form part of a lifting device 12 including a fixed mounting part 80 and a lifting block or lifting pulley 82 connected to an object 2 or load to be lifted.

The fixed mounting part 80 of the lifting device 12 is shown most clearly in Figures 2 to 5. In this embodiment the fixed mounting part 80 comprises two pulleys 20 including clamping portions 24 for securing the fixed mounting part 80 to threaded rods 14. The fixed mounting part 80 further comprises a support bar 84 and a pulley assembly or fixed pulley 86.

Each of the pulleys 20 includes a passage 88 in the support portion 26 for receiving a part of the support bar 84. The passage 88 preferably extends through the support portion 26 such that an axis 90 of the passage 88 extends in a direction perpendicular to the longitudinal axis 44 of the channel 38. In preferred embodiments the axis 90 of the passage 88, the longitudinal axis 44 of the channel 38 and the rotational axis 32 of the sheave 30 are orthogonal or perpendicular to each other.

The support bar 84 is preferably elongate and has a square or rectangular cross-sectional shape perpendicular to a longitudinal axis of the bar 84. The support bar 84 may be made of any suitable material such as wood, metal or plastic.

-17 -The cross-sectional shape and dimensions of the passage 88 in the pulley 20 is such that a part of the support bar 84 may be slidingly engaged with the passage 88. Preferably there is a frictional fit of the support bar 84 in the passage 88.

In use, it is envisaged that a pair of pulleys 20 will be clamped to a respective pair of threaded rods 14 as described above. The threaded rods 14, and therefore the pulleys 20, will typically be spaced apart. A first end section 92 of the support bar 84 is engaged with and extends through the passage 88 in a first one of the pulleys 20a and a second end section 94 of the support bar 84 is engaged with and extends through the passage in a second one of the pulleys 20b. In this way a central section 96 of the support bar 84 extends between the two pulleys 20a, 20b, as shown in Figure 2.

The pulley assembly or fixed pulley 86 is disposed in or on the central section 96 of the support bar 84. In particular the pulley assembly 86 preferably comprises a carriage 98 having a passage 100 through which the support bar 84 extends.

As shown most clearly in Figure 4, in this embodiment the carriage 98 of the pulley assembly 86 comprises a pair of carriage plates 102 held in a spaced apart configuration by a pair of spacer rods 104 attached to an upper edge region of the plates 102. The spacer rods 104 maintain a gap between the plates 102 to create the passage 100 in the carriage 98.

A pair of sheaves 106 is mounted between the carriage plates 102 in a lower region of the carriage 98. In this way the passage 100 is defined between the spacer rods 104, the plates 102 and the sheaves 106. In other words, the support bar 84 extends between the carriage plates 102, and between the spacer rods 104 and the sheaves 106. The sheaves 106 are spaced apart in a direction parallel to an axis of the passage 100, and therefore parallel to an axis 110 of the support bar 84 when present. The rotational axes 108 of the sheaves 106 are parallel to each other and each of the rotational axes 108 is preferably perpendicular to the axis of the passage 100 (and therefore perpendicular to the axis 110 of the support bar 84).

-18 -In the illustrated embodiment the pulley assembly 86 further comprises a lower spacer rod 112 that extends between the spacer plates 102 in the lower region of the carriage 98. The lower spacer rod 112 forms an anchor member 112 of the pulley assembly 86 in this embodiment. The anchor member 112 is disposed proximate one end of the pulley assembly 86, closer to a second one of the sheaves 106 than to a first one of the sheaves 106.

Referring now, in particular, to Figures 2 and 5, the fixed mounting part 80 of the lifting device 12 preferably comprises means to prevent or limit sliding of one or both of the pulleys 20 with respect to the support bar 84. In particular the fixed mounting part 80 of the lifting device 12 preferably comprises means to prevent or limit sliding of one or both of the pulleys 20 in a direction towards the pulley assembly 86, i.e. in a direction towards the central section 96 of the support bar 84. The fixed mounting part 80 of the lifting device 12 preferably also comprises means to prevent or limit sliding of the pulley assembly 86 with respect to the support bar 84, at least in one direction along the support bar 84.

In the illustrated embodiment, the fixed mounting part 80 of the lifting device 12 comprises means to prevent or limit sliding of a first one of the pulleys 20a in a first direction (towards the pulley assembly) 86 and means to prevent or limit sliding of the pulley assembly 86 in a second direction (towards the first one of the pulleys) 20a.

In this embodiment a first stop piece 114 is engaged with the support bar 84 proximate the first one of the pulleys 20a and a second stop piece 114 is engaged with the support bar 84 proximate the pulley assembly 86. Each of the stop pieces 114 is secured to the support bar 80 in a fixed position and provides an abutment surface against which the corresponding pulley 20 or pulley assembly 86 may abut if the pulley 20 or pulley assembly 86 slides with respect to the support bar 84.

Although in this embodiment the means to prevent or limit sliding of one or both of -19 -the pulleys 20 with respect to the support bar 84 and the means to prevent or limit sliding of the pulley assembly 86 with respect to the support bar 84 are shown as separate components, in other embodiments the means to prevent or limit sliding of the pulley 20 with respect to the support bar 84 may be integrally formed with and be part of the pulley 20. Similarly, the means to prevent or limit sliding of the pulley 86 assembly with respect to the support bar 84 may be integrally formed with and be part of the pulley assembly 86. The means to prevent or limit sliding of one or both of the pulleys 20 and the means to prevent or limit sliding of the pulley assembly 86 may, for example, include a clamping or gripping arrangement to apply a clamping or gripping force to the support bar 84. The means to prevent or limit sliding of one or both of the pulleys 20 and the means to prevent or limit sliding of the pulley assembly 86 may comprise a peg or protrusion that engages with a recess or hole in the support bar 84.

Referring now to Figures 1, 16 and 18, the lifting block or lifting pulley 82 comprises a pulley shell 116 in which is mounted a sheave 118. A swivel 120 is connected to the pulley shell 116 at a first or lower end of the pulley shell 116. The swivel 120 forms a mount 121 of the lifting pulley 82.

The pulley shell 116 may include one or more sheaves 118. In the illustrated example the lifting pulley 82 comprises two sheaves 118. When the lifting pulley 82 comprises two or more sheaves 118 it is preferable if the rotational axes 122 of the sheaves 118 are coaxial.

In use the lifting pulley 82 is connected to an object 2 to be lifted by the swivel 120.

The swivel 120 is configured to allow rotation of the object 2 about an axis 124 perpendicular to the rotational axis 122 of the sheave 118. In practice the object 2 is able to rotate about an axis 124 that extends substantially parallel to the direction of lift of the object 2. This axis 124 of rotation may be substantially vertical. To facilitate this rotation, the swivel 120 is preferably rotationally connected to the pulley shell 116.

-20 -In preferred embodiments an object 2 to be lifted is supported in a sling or cradle 16. The sling or cradle 16 is then attached to the lifting pulley 82 and in particular to the swivel 120 of the lifting pulley 82.

The sling 16 comprises one or more straps 126 that, in use, extend around the object 2. Typically the sling 16 will include at least two straps 126 arranged in a cross configuration. In this way the object 2 may be held securely by the straps 126 during lifting of the object 2.

In the illustrated embodiment the sling 16 further comprises a spreader plate or support board 128. The support board 128 includes a mount 130 for attaching the support board 128 to the swivel 120 of the lifting pulley 82. The straps 126 of the sling 16 extend from edge regions of the support board 128. In use the object 2 to be lifted is secured in the sling 16 by the straps 126 such that a part of the object 2 is in contact with the support board 128 and the support board 128 is disposed between the object 2 and the lifting pulley 82.

The support board 128 preferably has dimensions (or aspect ratio) that correspond to or are appropriate for the size and shape of the object 2 being lifted. In particular, it is advantageous if a first, width dimension (W) of the support board 128 is only slightly less than a width dimension of the object 2 and a second, length dimension (L) of the support board 128 is only slightly less than a length dimension of the object 2. This minimises distances between edges of the support board 128 and top edges of the object 2. The support board 128 is configured to spread or distribute the weight of the load or object being lifted for stability. This, in turn, results in a more secure sling 16 and, in particular, minimises the likelihood that the object 2 will slip out of the sling 16 between the straps 126.

Two embodiments of a support board 128 are illustrated in Figures 14 and 15. These support boards 128 are designed to securely support different types and sizes of air conditioning fan-coil unit.

-21 -Figure 17 shows a preferred embodiment of the mount 130 of the support board 128. The mount 130 comprises a pair of pivot plates 132 spaced apart to receive a part of the swivel 120 between them. Each pivot plate 132 includes a hole 134 and the holes 134 of the pivot plates 132 are aligned. A lock pin 136 is attached to the support board 128 by a lanyard 138 or length of flexible cord.

To engage with and be secured to such a mount 130, the swivel 120 of the lifting pulley 82 comprises a through-hole 140. To attach the lifting pulley 82 to the support board 128, a part of the swivel 120 is located between the pivot plates 132 such that the through-hole 140 aligns with the holes 134 of the pivot plates 132. The lock pin 136 can then be inserted through the aligned holes 134, 140. Preferably the dimensions of the lock pin 136 and the holes 134, 140 is such that there is a friction fit of the lock pin 136 in the holes 134, 140 to secure the lifting pulley 82 to the mount 130.

It will appreciated that in other embodiments the lock pin 136 may be separate from the support board 128; however, the lock pin 136 is advantageously attached to the support board 128 to minimise the risk of the lock pin 136 being lost. In yet further embodiments the mount 130 of the support board 128 may be of any suitable configuration to connect to the mount 121 of the lifting pulley 82.

The connection of the lifting pulley 82 to the support board 128 is preferably such that the support board 128 can be rotated about an axis perpendicular to the rotational axis of the swivel 120. In use this means that the support board 128, and therefore the object in the sling 16, has three degrees of rotational freedom. This advantageously allows the object 2 to be manoeuvred easily into position once it has been raised, for example to align the object 2 with and secure the object 2 to the threaded rods 14.

Referring to Figures 1 and 13, an embodiment of the invention is shown in which a lifting device 12 is secured to a pair of threaded rods 14 (attached to a ceiling structure) and is configured to raise an air conditioning unit 2 supported in a sling 16. The lifting device 12 comprises a first pulley 20a clamped to a first one of the threaded rods 14a and a second pulley 20b clamped to a second one of the threaded rods 14b. The support bar 84 extends between the first and second pulleys 20a, 20b and through the passages 88 in each of the pulleys 20. A pulley assembly 86 is disposed centrally between the first and second pulleys 20a, 20b on the support bar 84.

In this embodiment the lifting device 12 is arranged to lift the bulky air conditioning unit 2 towards the threaded rods 14 so that the air conditioning unit 2 can then be attached to the threaded rods 14 so as to secure the air conditioning unit 2 to the ceiling structure. In most cases, the air conditioning unit 2 will be secured at each of its four corners to a respective threaded rod 14. As such, in order to lift the air conditioning unit 2 such that the air conditioning unit 2 remains level and in a suitable orientation for attachment to the threaded rods 14, the pulleys 20 of the lifting device 12 are preferably secured to threaded rods 14 disposed diagonally across the mounting area of the air conditioning unit 2. In other words, the support bar 84 of the lifting device 12 extends substantially diagonally across an upper surface of the air conditioning unit 2, as illustrated in Figure 13.

The sling 16 is secured around the air conditioning unit 2. The support board 128 of the sling 16 extends over the upper surface of the air conditioning unit 2 and the straps 126 extend and wrap around sides and a lower surface of the air conditioning unit 2. It will be appreciated that, in use, the lifting pulley 82 is disposed substantially vertically below the pulley assembly 86, such that the air conditioning unit 2 is lifted in a substantially vertical direction towards the threaded rods 14.

Referring now again to Figure 1, in this illustrated embodiment, a length of rope 4 is engaged with the sheave 30 of the pulley 20, the sheaves 106 of the fixed pulley assembly 86 and the sheaves 118 of the lifting pulley 82. A first end 400 of the rope 4 is secured to the anchor member 112 of the pulley assembly 86. A first section 402 of the rope 4 extends between the anchor member 112 and a first sheave 118a of the lifting pulley 82. The rope 4 extends around the sheave 118a and a second -23 -section 404 of the rope 4 extends between the lifting pulley 82 and a first sheave 106a of the pulley assembly 86. The rope 4 extends around this sheave 106a and a third section 406 of the rope 4 extends between the pulley assembly 86 and a second sheave 118b of the lifting pulley 82. The rope 4 extends around the second sheave 118b of the lifting pulley 82. In this example, the rope 4 extends around the second sheave 118b of the lifting pulley 82 in an opposite direction to the direction that the rope 4 extends around the first sheave 118a of the lifting pulley 82. In this way, when a user pulls the rope 4 to raise the object 2 (as described below) the second sheave 118b of the lifting pulley 82 rotates in an opposite direction to the first sheave 118a of the lifting pulley 82.

A fourth section 408 of the rope 4 extends between the lifting pulley 82 and a second sheave 106b of the pulley assembly 86. In this example, the second sheave 106b of the pulley assembly 86 is closer to the anchor member 112 than the first sheave 15 106a of the pulley assembly 86. The rope 4 extends around the second sheave 106b of the pulley assembly 86 and a fifth section 410 of the rope 4 extends between the pulley assembly 86 and the pulley 20. The pulley assembly 86 is preferably oriented such that the second sheave 106b is closer to the pulley 20 than the first sheave 106a. The fifth section 410 of the rope 4 extends over the sheave 30 of the pulley 20 and a sixth section 412 of the rope 4 extends between the cams 76 of the cam cleat 74. The sixth section 412 of the rope 4 terminates at a second, free end 414 of the rope 4.

It will be understood that the second pulley 20b of the lifting device 12 is used to 25 secure the support bar 84 to the threaded rod 14b, but does not form part of the rope and pulley system in this embodiment.

To lift the air conditioning unit 2 (or other object in other embodiments), a user pulls on the free end 414 of the rope 4 in a direction away from the pulley 20a. The configuration of the rope 2, fixed pulley assembly 86 and lifting pulley 82 means that the lifting pulley 82, and therefore the sling 16, is raised in a direction towards the threaded rods 14.

-24 -The pulleys 20 are preferably secured to the threaded rods 14 such that an end region of each of the threaded rods 14 extends from the respective channel 38 of the pulley 20 below the pulley 20. When the air conditioning unit 2 (or other object) has been raised sufficiently such that the air conditioning unit 2 is proximate to the ends of the threaded rods 14, the unit 2 may be rotated or tilted to align the threaded rods 14 with the parts of the unit 2 to be secured to the threaded rods 14. In preferred embodiments the air conditioning unit 2 (or other object) is then secured directly to the threaded rods 14, with the lifting device 12 still supporting the weight of the unit 2. A user may release his hold on the rope 4 while securing the unit 2 to the threaded rods 14 as the rope 4 will be held by the cam cleat 74 as described above.

Once the air conditioning unit 2 has been secured to the threaded rods 14 such that the weight of the unit 2 is now supported by the threaded rods 14, the lifting device 12 can be detached from both the unit 2 and the threaded rods 14. It will be appreciated that the lifting device 12 is disposed above the air conditioning unit 2 (or other object) relative to the lower ends of the threaded rods 14. As such, it is desirable if the pulleys 20 can be detached from the threaded rods 14 without requiring the pulleys 20 to slide over the ends of the threaded rods 14.

In preferred embodiments, therefore, the locking member 56 of each of the pulleys 20 is released which then allows the first and second wings 34, 36 of the clamping portion 24 to move with respect to each other. In particular, the second wing 36 can be rotated about the hinge 48 to open the channel 38. The threaded rod 14 can then be removed from the channel 38 in a direction away from the hinge 48 and in a direction substantially perpendicular to the longitudinal axis 44 of the channel 38 (and accordingly in a direction substantially perpendicular to an axis of the threaded rod 14).

The sling 16 can then be released from the air conditioning unit 2 or other object.

The sling 16 may be released before or after the pulleys 20 are detached from the threaded rods 14. It will be appreciated that the lifting device 12 is relatively compact, -25 -and as such, even if space around the unit 2 is limited once the unit 2 has been secured to the threaded rods 14, the lifting device 12 can still be easily removed.

After detachment and removal of the lifting device 12, the air conditioning unit 2 or 5 other object can then be repositioned and/or more securely fastened to the threaded rods 14, if required.

In other embodiments, for example, when it is desired to lift a smaller, lighter or less bulky object, a single pulley 20 may be used to lift the object. In these embodiments a length of rope 4 extends around the sheave 30 of the pulley 20. A first end of the rope 4 is attached to the object to be lifted and a second end of the rope 4 is a free end, to be pulled by the user. The first end of the rope 4 may be secured to a sling 16 in which the object is supported.

In another embodiment of the invention the sling comprises a lifting beam, such as the lifting beam illustrated in Figure 19. The lifting beam 242 comprises an elongate bar 244 that extends between first and second ends 246, 248. The bar 244 is preferably tubular, such that a bore extends along the length of the bar 244. Each of the first and second ends 246, 248 of the bar 244 may be closed ends.

The lifting beam 242 comprises a mount 230 for attaching the lifting beam 242 to the swivel 120 of the lifting pulley 82. The mount 230 is preferably disposed midway along the length of the bar 244 between the first and second ends 246, 248. In this embodiment the mount 230 comprises a recess or aperture 250 in a first, upper surface 252 of the bar 244. The recess 250 defines first and second side walls 254 of the mount 230, which in this embodiment are part of first and second sides 256, respectively, of the bar 244. Each of the first and second side walls 254 of the mount 230 comprises a hole 234 and the holes 234 of the side walls 254 are aligned. A lock pin 236 is attached to the lifting beam 242 by a lanyard 238 or length of flexible cord.

To attach the lifting pulley 82 to the lifting beam 242, a part of the swivel 120 of the -26 -lifting pulley 82 is located in the recess 250 between the side walls 254. The dimensions of the recess 250 are, therefore, substantially the same as or slightly larger than the dimensions of the swivel 120 of the lifting pulley 82. The swivel 120 is positioned in the recess 250 such that the through-hole 140 of the swivel 120 aligns with the holes 234 of the side walls 254 of the recess 250. The lock pin 236 can then be inserted through the aligned holes 234, 254. Preferably the dimensions of the lock pin 236 and the holes 234, 254 are such that there is a friction fit of the lock pin 236 in the holes 234, 254 to secure the lifting pulley 82 to the mount 230.

In this embodiment the lifting beam 242 further comprises a plurality of stops or detents 258 disposed along the upper surface 252 of the bar 244. A first set of stops 258 are disposed between the first end 246 of the bar 244 and the recess 250 and a second set of stops 258 are disposed between the second end 248 of the bar 244 and the recess 250. Each of the stops 258 comprises a projection, which in this embodiment is in the form of a plate member 260, extending from the upper surface 252 of the bar 244.

The lifting beam 242 is configured to spread or distribute the weight of the load or object being lifted for stability. Accordingly a length of the bar 244 is preferably substantially the same as or is appropriate for the size and shape of the object being lifted. In use, one or more straps are engaged with the load to be lifted and are looped over the bar 244 so as to secure the load to the bar 244. Preferably a first part of the strap or straps extends over a first part of the bar 244 proximate the first end 246 of the bar 244 and adjacent at least one of the stops 258 of the first set of stops 258. Preferably a second part of the strap or straps extends over a second part of the bar 244 proximate the second end 248 of the bar 244 and adjacent at least one of the stops 258 of the second set of stops 258. Each of the stops prevents the strap sliding along the bar 244 and sliding off the respective end 246, 248 of the bar 244. The strap or straps engage with the load such that the lifting beam 242 extends across an upper surface of the load. The strap or straps may be wrapped or looped around the load. The strap is preferably adjustable so that the strap may be tightened around the load.

-27 -The load may then be lifted by the lifting device as described above.

In some embodiments the fixed pulley assembly 86 may comprise only one sheave 106. In these embodiments, a first end of a length of rope 4 is secured to the anchor member 112 of the pulley assembly 86. A first section of the rope 4 extends from the anchor member 112 to the lifting pulley 82 attached to the object to be lifted. The rope 4 extends around the sheave 118 of the lifting pulley 82 and a second section of the rope 4 extends from the lifting pulley 82 to the sheave 106 of the pulley assembly 86. The rope 4 extends around the sheave 106 of the pulley assembly 86 and a third section of the rope 4 extends between the pulley assembly 86 and the pulley 20. The rope 4 extends over the sheave 30 of the pulley 20 and a fourth section of the rope 4 extends between the cams 76 of the cam cleat 74. The fourth section of the rope 4 terminates at a second, free end of the rope.

In some embodiments the pulley assembly 86 may comprise more than two sheaves 106. In these embodiments the rope will extend around one or more of the sheaves as required to form a number of rope sections, and the resultant desired mechanical advantage.

Other modifications and variations not explicitly disclosed above may also be contemplated without departing from the scope of the invention as defined in the appended claims.

Claims

-28 -CLAIMS1. A pulley comprising: a main body including a channel for receiving a length of threaded rod, the channel having a deformable lining, and the main body being moveable between an open configuration in which a length of threaded rod is insertable into the channel and a closed configuration in which, in use, the channel grips said length of threaded rod by deformation of the lining; a locking member arranged to secure the main body in the closed configuration; and a sheave.
2. A pulley as claimed in Claim 1, in which in the open configuration a length of threaded rod is insertable into the channel in a direction perpendicular to an axis of the channel.
3. A pulley as claimed in Claim 1 or Claim 2, in which the main body comprises a first clamping portion and a second clamping portion, each of the first and second clamping portions including a part of the channel and the first and second clamping portions being hingedly connected to each other to permit the second clamping portion to move with respect to the first clamping portion between the open and closed configurations.
4. A pulley as claimed in any preceding claim, in which the sheave is mounted 25 on a support bracket extending from the main body.
5. A pulley as claimed in any preceding claim, further comprising a cam cleat.
6. A pulley as claimed in any preceding claim, in which the main body comprises a passage for receiving a support bar, an axis of the passage extending substantially perpendicular to an axis of the channel.
7. A pulley as claimed in Claim 6, wherein a rotational axis of the sheave is perpendicular to each of the axis of the passage and the axis of the channel.
8. A lifting device comprising: a first pulley as claimed in Claim 6 or Claim 7; a second pulley as claimed in Claim 6 or Claim 7; and an elongate support bar extending through the passage in the first pulley and through the passage in the second pulley, such that the first pulley is spaced from the second pulley and a central section of the support bar extends between the first pulley and the second pulley.
9. A lifting device as claimed in Claim 8, further comprising: a fixed pulley engaged with the central section of the support bar, the fixed pulley comprising a carriage including a passage through which the support bar 15 extends and a sheave; means for preventing sliding of the first pulley along the support bar in a first direction; and means for preventing sliding of the fixed pulley along the support bar in a second direction, the second direction being opposite the first direction.
10. A lifting device as claimed in Claim 9, in which the fixed pulley comprises two sheaves, the sheaves being spaced apart in a direction parallel to an axis of the support bar.
11. A lifting device as claimed in Claim 9 or Claim 10, wherein a rotational axis of the or each sheave of the fixed pulley is perpendicular to an axis of the support bar.
12. A lifting device as claimed in any one of Claims 8 to 11, further comprising a lifting pulley including a mount for attachment to a load to be lifted by the lifting device and a sheave.
-30 - 13. A lifting device as claimed in Claim 12, in which the lifting pulley comprises two sheaves having a common rotational axis.
14. A lifting device as claimed in Claim 12 or Claim 13, wherein the mount comprises a swivel.
15. A lifting device as claimed in any one of Claims 12 to 14, further comprising a sling for supporting a load to be lifted by the lifting device, the sling comprising at least one strap, and the sling being connected to the mount of the lifting pulley.
16. A lifting device as claimed in Claim 15, in which the sling comprises a spreader board connected to the mount of the lifting pulley, and the strap is connected to and extends from the spreader board.
17. A lifting device as claimed in Claim 15, in which the sling comprises a lifting beam connected to the mount of the lifting pulley, and the strap is engaged with the lifting beam.
18. A lifting device as claimed in any one of Claims 8 to 17, further comprising an elongate length of rope engaged with the or each sheave.
19. A lifting assembly comprising: a lifting device as claimed in any one of Claims 8 to 18; a first threaded rod; and a second threaded rod, wherein, the first pulley is engaged with the first threaded rod and the second pulley is engaged with the second threaded rod.
20. A lifting assembly as claimed in Claim 19, wherein the lifting device is as claimed in Claim 18 when dependent on Claim 15, and in which a load to be lifted is secured in the sling. -31 -
21. A lifting assembly as claimed in Claim 20, wherein the load to be lifted is an air conditioning unit.
22. A method of lifting a load using a pulley comprising: inserting a length of threaded rod into a channel of a main body of the pulley with the main body in an open configuration; clamping the threaded rod in the channel by moving the main body into a closed configuration in which a deformable lining of the channel grips the threaded rod; engaging a locking member to secure the main body in the closed configuration; engaging a length of rope with a sheave of the pulley; connecting a first part of the length of rope on a first side of the sheave to the load to be lifted; and applying a force to a second part of the length of rope on a second side of the sheave so as to lift the load.
23. A method as claimed in Claim 22, wherein the threaded rod is inserted into the channel in a direction substantially perpendicular to a longitudinal axis of the 20 channel.
24. Use of the lifting device of Claim 9 comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; clamping the second threaded rod in the channel by moving the main body -32 -of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheave of the fixed pulley and the sheave of the first pulley; connecting a first end portion of the length of rope to a load to be lifted; and - applying a force to a second end portion of the length of rope so as to lift the lift. 10
25. Use of the lifting device of Claim 13 comprising the steps of: - inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; - clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; - engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; - clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; - engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth -33 -section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; attaching the mount of the lifting pulley to a load to be lifted; and applying a force to the second end of the length of rope so as to lift the load.
26. Use of the lifting device of Claim 16 comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; securing a load to be lifted in the sling such that the spreader board extends over a part of the load and the strap extends around the load; and applying a force to the second end of the length of rope so as to lift the load.-34 -
27. Use of the lifting device of Claim 17 comprising the steps of: inserting a length of a first threaded rod into the channel of the first pulley with the main body in an open configuration; clamping the first threaded rod in the channel by moving the main body of the first pulley into a closed configuration in which a deformable lining of the channel grips the first threaded rod; engaging a first locking member to secure the main body of the first pulley in the closed configuration; inserting a length of a second threaded rod into the channel of the second pulley with the main body in an open configuration; clamping the second threaded rod in the channel by moving the main body of the second pulley into a closed configuration in which a deformable lining of the channel grips the second threaded rod; engaging a second locking member to secure the main body of the second pulley in the closed configuration; engaging a length of rope with the sheaves of the fixed pulley, the first pulley, and the lifting pulley such that a first end of the rope is fixedly secured to the fixed pulley, a first section of the rope extends between the fixed pulley and a first sheave of the lifting pulley, a second section of the rope extends between the lifting pulley and a first sheave of the fixed pulley, a third section of the rope extends between the fixed pulley and a second sheave of the lifting pulley, a fourth section of the rope extends between the lifting pulley and a second sheave of the fixed pulley, a fifth section of the rope extends between the fixed pulley and the first pulley, and a sixth section of the rope terminates at a second end of the rope; securing a load to be lifted in the sling such that the lifting beam extends over a part of the load and the strap extends around the load; and applying a force to the second end of the length of rope so as to lift the load.