GB2542866A

GB2542866A - Lifting apparatus

Info

Publication number: GB2542866A
Application number: GB1600004.4A
Authority: GB
Inventors: Evans Barry
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-09-21
Filing date: 2016-01-04
Publication date: 2017-04-05
Anticipated expiration: 2036-01-04
Also published as: GB201516654D0; GB201600004D0; GB2550532A; GB2542866B

Abstract

A lifting device, in particular for lifting a concrete cable trough 12, comprises a frame including a crossbar 20, a handle (26 fig. 1) connected to and extending at right angles to the crossbar 20, a load engagement formation 32 extending from the crossbar 20 and load carriers 48 connected to spaced locations on the crossbar 20, each load carrier 48 having a load supporting formation 46 that can be moved between a withdrawn position and an operative position in which the supporting formations 46 are more closely spaced than in the withdrawn position such that a force applied to the handle (26 fig. 1) in a lifting direction tends to cause the frame to pivot about the load supporting formations 46 to urge the load engagement formation 32 into contact with an article 12 to be lifted. The load supporting formations 46 may pivot between the withdrawn and the operative positions. Two such lifting devices may form a lifting apparatus. The load supporting formations 46 may engage a bottom surface of a trough 12 and the load engagement formation 32 may be urged against an upper surface of a base of a trough 12. The handle 26 (fig. 7) may include two grips (134, 134 fig. 7). Components of the device handled by a user such as the handle may be electrically insulated and made from an electrically insulating material such as glass reinforced plastic.

Description

Lifting Apparatus

This invention related to lifting apparatus. In particular, it relates to apparatus for lifting a concrete trough.

Lifting heavy items presents considerable risk of personal injury. This risk is increased through repetition, and in uncontrolled environments (such as when working outdoors, on-site), where a person undertaking a lifting operation may have to adapt to variations in their environment, such as the ground on which they are standing. Lifting is particularly hazardous where heavy object must be hfted to or from ground level, since this can involve bending. While mechanical lifting equipment, such as cranes, hoists and jacks are known, they are often unsuited to ad-hoc tasks, such as installing multiple objects in various conditions on site.

In the following description, reference will be made to the installation of cable troughs, but it must be understood that the invention is not limited to that application.

An aim of this invention is to provide apparatus to enable safe lifting of heavy items from ground level.

To this end, the present invention provides a lifting device comprising one or more of: a) a frame including a crossbar; b) a handle connected to and extending at right angles to the crossbar; c) a load engagement formation extending from the crossbar; d) load carriers connected to spaced locations on the crossbar, each load carrier having a load supporting formation that can be moved between a withdrawn position and an operative position, wherein the supporting formations are more closely spaced in the operative position than in the withdrawn position; wherein e) a force applied to the handle in a lifting direction tends to cause the frame to pivot about the load supporting formations to urge the load engagement formation into contact with an article to be lifted.

The load supporting formations may pivot between the withdrawn and operative positions. In preferred embodiments, the load supporting formations are carried on a rod that can pivot with respect to the crossbar. The rod may have a cranked portion that extends in a direction generally parallel to the supporting formations, to serve as a handle to enable rotation of the rod.

The crossbar and the load supporting formations may be in a common plane and the load engagement formation is displaced from the plane in a direction opposite to that in which the handle extends.

Each supporting formation may be carried on a respective assembly that is removably connected to the frame for use. Each assembly is preferably connected to the frame in a plurality of positions, whereby the distance between the supporting formations can be adjusted.

From a second aspect, this invention provides lifting apparatus comprising two lifting devices, each embodying the first aspect of the invention.

From a third aspect, this invention provides a method of lifting a trough comprising placing a respective lifting device according to any one of claims 1 to 8 at each end of a trough and moving the supporting formations to the operative position and lifting the handle, whereby the supporting formations engage a bottom surface of the trough, and the load engagement formation is urged against an upper surface of a base of the trough.

Since it is likely that embodiments of the invention will be used in proximity to live electrical cables, preferably components handled by a user in use are electrically insulated. For example, the handle may be formed from an electrically non-conductive material. A lifting device may include a second frame, handle, load engagement member and load carriers as set forth above, the handles being interconnected by an extension such that the handles project in opposite directions from a central plane of symmetry.

An embodiment of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings, in which:

Figures 1 and 2 are perspective and front views of a lifting device being an embodiment of the invention;

Figure 3 is a sectional view of the embodiment of Figures 1 and 2;

Figures 4, 5 and 6 show the embodiment of Figures 1 and 2 being used to lift a concrete cable trough;

Figure 7 is a diagrammatic view of an alternative embodiment of the invention;

Figure 8 is a diagrammatic view of a further alternative embodiment of the invention; and

Figure 9 shows a fourth embodiment of the invention.

As shown in the drawings, a first embodiment of the invention is intended to be used for lifting U-section concrete troughs 10, as shown in Figures 4 to 6. These troughs are typically laid end-to-end adjacent to a railway line to provide an enclosure for cables. Once the cables have been installed, the troughs are capped with a concrete slab. It will be appreciated that the presence of ballast and uneven ground makes standing and lifting these troughs difficult and potentially hazardous. The toughs have a flat base 12 and opposite upright side walls 14.

With reference now to Figures 1 to 3, a lifting device embodying the invention includes a frame that is constructed from welded members. The frame includes a crossbar 20 of square cross-section. A handle 26 of circular cross-section extends through the crossbar 20 and is secured to it by welding. The handle 26 projects at a centre point of opposite front and rear walls of the crossbar 20. From the front wall, the short portion 28 of the handle 26 projects perpendicular to the wall. A leg 30 projects at right angles from the short portion 28. A transverse bar 32 is secured to the leg at its end remote from the crossbar 20, the transverse bar 32 being of square section and extending parallel to the crossbar 20. The direction in which the leg 30 extends will be referred to as “down”, and the opposite direction as “up”. From the rear wall of the crossbar 20, the handle 26 projects initially perpendicular and in a direction opposite to that of the short portion 28. It is then curves, such that an intermediate section of the handle 26 extends upwards at an angle of approximately 20°. A further curve means that an end portion of the handle 26 extends downwards at an angle of approximately 10°, which end portion carries a grip 34. A vertical hole is formed through the crossbar 20 on opposite sides of the handle.

The lifting device further includes two similar side assemblies. Each side assembly has an T-piece that has a tubular upright 40 and a connecting piece 42, the connecting piece 42 extending perpendicular to the upright 40 close to one of its ends. Two spaced holes extend vertically through the connecting piece 42.

Each side assembly further includes a lifting rod 44. The lifting rod 44 has a lower portion that extends through the upright 40 to project from upper and lower ends of the upright 40. At the lower end of the lifting rod 44, a lug 46 that serves as a load carrier and that projects perpendicularly close to the lower end of the upright 40. The lug is too large to enter the upright 40, thereby limiting the extent to which the lifting rod 44 can move upward within the upright. The lifting rod 44 extends from the upper end of the upright 40 and has a cranked end handle portion 48 that is perpendicular to the lower portion and is in a direction parallel to the extent of the lug 46. A peg 52 extends transversely through the lifting rod 44 close to the upper end of the upright 40. The peg 52 is too large to enter the lifting rod, and thereby limits downward movement of the lifting rod 44 into the upright 40.

To assemble the lifting device for use, the connecting piece 42 of each side assembly is inserted into the crossbar 20 of the frame such that the upright 40 is parallel to and extends in the same direction as the leg 30. The connecting piece is positioned within the crossbar 20 such that one of its holes aligns with a hole in the crossbar 20. A locking pin 56 is then inserted through the holes to secure the connecting piece 42 within the crossbar 20. Since there is more than one hole in the connecting piece, the distance between the uprights 40 can be selected to be just wider than a trough to be lifted.

Once assembled, the lifting rods 44 are turned using the handle potions 48 within the uprights 40 such that the lugs 46 (and the handle portions 48) extend parallel to one another in a withdrawn position. The lifting device is then placed over a trough to be lifted such that the uprights 40 are adjacent to the opposite walls 14 and near to one end of the trough 10 and the handle 26 extends from the end of the trough. The lifting rods 44 are then turned such that their handle portions 48 extend towards one another in an operative position, which causes the lugs 46 to project under the base 12 of the trough 10. The transverse bar 32 makes contact with the upper surface of the base 12. Tiffing apparatus embodying the invention typically comprises two substantially identical lifting devices whereby a respective lifting device can be installed in this manner at both ends of a trough to be lifted.

The trough 10 can now be lifted and moved by two people, each one grasping and lifting the handle 26 of a respective lifting device. As the handle 26 is lifted, the lifting device pivots about the lugs 46, which urges the transverse bar 32 into contact with the base 12, so preventing the lifting device from rotating with respect to the trough. The weight of the trough is borne by the pegs 52 bearing against the tops of the uprights 40.

Since the handle is raised above the trough, the people need not bend to round level to lift the trough. The lifting device affords a secure grip upon the trough 10, which means that the people lifting do not have to struggle for grip and can concentrate on handling the trough safely and on maintaining a secure footing.

An alternative arrangement of a lifting device embodying the invention is shown in Figure 7. The difference between this embodiment and that described above is in the configuration of the handle 26. Remote from the crossbar 20, the handle 26 of this embodiment has a crosspiece 120 that extends parallel to the crossbar 20. From opposite end portions of the crosspiece 120, a respective grip 134, 134' projects. Using this embodiment, a person can use both hands when lifting a rough 10 as described above, or two people can share the load. A third embodiment is shown in Figure 8. This embodiment can be considered to comprise two of the lifting devices described above (either embodiment) connected together, symmetrically about a centre plane A by an extension 128 of the short portion 28 of the handle 26. The remaining components are as described with reference to the first embodiment.

The components of the embodiments described above will generally be formed from steel tube or bar, as appropriate. Typically, embodiments of this invention will be used in proximity to electrical cables, which may be live with potentially dangerous voltages, and the fact that they will therefore be a good conductor of electricity could present a risk to an operator. Therefore, it is preferred that some or all of the components of embodiments of the invention, particularly those components which are grasped by a user during use, are enclosed within a tube of insulating material. The grips 34, 134 may be similarly insulated. Alternatively, they may, for additional safety, be separate components to be applied to the handle 26 made of an insulating material, such as glass-reinforced plastic. As a further alternative, the entire handle 26 may be made as a tube of glass-reinforced plastic or other insulating material.

The embodiment of Figure 9 includes some variations on the preceding embodiments. These variations will now be described.

The handle portions 48 of the lifting rods 44 are enclosed within insulating hand grips 144.

The handle 126 is made of an insulating material: glass-reinforced plastic in this embodiment.

The pins 152 are each connected to the device by a respective lanyard 154.

The leg 130 is adjustable such that the distance between the transverse bar 132 and the crossbar 120 can be varied to accommodate a range of different sizes of trough. This is achieved by mounting the transverse bar 132 on a strut 134 that can be secured to a lower part of the leg 130 in one of several positions.

Claims

1. A lifting device comprising: a) a frame including a crossbar; b) a handle connected to and extending at right angles to the crossbar; c) a load engagement formation extending from the crossbar; d) load carriers connected to spaced locations on the crossbar, each load carrier having a load supporting formation that can be moved between a withdrawn position and an operative position, wherein the supporting formations are more closely spaced in the operative position than in the withdrawn position; wherein e) a force applied to the handle in a lifting direction tends to cause the frame to pivot about the load supporting formations to urge the load engagement formation into contact with an article to be lifted.

2. A lifting device according to claim i in which the load supporting formations pivot between the withdrawn and operative positions.

3. A lifting device according to claim 2 in which the load supporting formations are carried on a rod that can pivot with respect to the crossbar.

4. A lifting device according to claim 3 in which the rod has a cranked portion that extends in a direction generally parallel to the supporting formations.

5. A lifting device according to any preceding claim in which the crossbar and the load supporting formations are in a common plane and the load engagement formation is displaced from the plane in a direction opposite to that in which the handle extends.

6. A lifting device according to any preceding claim in which each supporting formation is carried on a respective assembly that is removably connected to the frame for use.

7. A lifting device according to claim 6 in which each assembly can be connected to the frame in a plurality of positions, whereby the distance between the supporting formations can be adjusted.

8. A lifting device according to any preceding claim in which the handle includes two spaced grips that can be simultaneously gripped by a user.

9. A lifting device according to any preceding claim in which components handled by a user in use are electrically insulated.

10. A lifting device according to any preceding claim in which the handle is formed from an electrically non-conductive material.

11. A lifting device according to any preceding claim further including a second frame, handle, load engagement member and load carriers as set forth in any preceding claim, the handles being interconnected by an extension such that the handles project in opposite directions from a central plane of symmetry.

12. A lifting device substantially as described herein with reference to Figures 1 to 6 of the drawings.

13. A lifting device substantially as described herein with reference to Figures 1 to 6 of the drawings as modified in accordance with figure 7, 8 or 9 of the drawings.

14. Lifting apparatus comprising two lifting devices, each according to any preceding claim.

15. A method of hfting a trough comprising placing a respective lifting device according to any one of claims 1 to 8 at each end of a trough and moving the supporting formations to the operative position and hfting the handle, whereby the supporting formations engage a bottom surface of the trough, and the load engagement formation is urged against an upper surface of a base of the trough.