WO2011015977A2

WO2011015977A2 - Improved stabiliser leg

Info

Publication number: WO2011015977A2
Application number: PCT/IB2010/053467
Authority: WO
Inventors: Andrew Alexander Brown; Peter Ross Brewitt; Gregory David Muirsmeath; John Harris Steel
Original assignee: Steelbro New Zealand Limited
Priority date: 2009-08-03
Filing date: 2010-07-30
Publication date: 2011-02-10
Also published as: WO2011015977A3

Abstract

A stabiliser for use in stabilising cranes, wherein the stabiliser includes a housing which is adapted to be pivotally mounted upon a mounting and which is provided with a first moving means adapted to alter the position of the housing relative to the mounting between a first position in which the housing is inclined towards the mounting at an acute angle to the mounting and a second position in which the housing is extended away from the mounting.

Description

Title: Improved Stabiliser Leg

Field of the Invention The present invention relates to a stabiliser for use in stabilising hoists and cranes (hereinafter referred to as "cranes"), particularly, but not exclusively, vehicle mounted cranes of the type used to lift the loads onto and off vehicle decks. As used herein, the term "vehicle" includes trucks, trailers, semitrailers, railway wagons, or similar means of transport.

Background of the Invention

It is common practice to use a stabiliser of one form or another to stabilise vehicles when loads are being lifted on to or off the vehicle. A wide variety of different configurations of stabiliser have been employed for this purpose.

Object of the Invention

It is an object of the present invention to provide a stabiliser which furnishes the end- user with a useful choice.

Disclosure of the Invention

The present invention provides a stabiliser for use in stabilising cranes, wherein the stabiliser includes a housing which is adapted to be pivotally mounted upon a mounting and which is provided with a first moving means adapted to alter the position of the housing relative to the mounting between a first position in which the housing is inclined towards the mounting at an acute angle to the mounting and a second position in which the housing is extended away from the mounting.

Preferably, the stabiliser further includes a primary leg pivotally mounted to the housing at a position remote from the pivotal mounting of the housing to the mounting; and a second moving means connected between the primary leg and the housing and adapted to pivot the primary leg relative to the housing between a first position in which said leg is folded back towards said housing, and a second position in which, when the housing is in its second position, the housing and the primary leg respectively form the top and one side of an arch.

Preferably, in the second position of the housing, the housing is substantially horizontal, and in the second position of the primary leg, the primary leg is substantially vertical.

Preferably, the stabiliser further includes an extension leg telescopically mounted within the housing, said extension leg being extensible and retractable relative to the housing by a further moving means.

Preferably also, said first moving means is pivotally secured to said mounting at one end and at the other end is pivotally secured between one end of each of a pair of arms, the other ends of which are pivoted to said mounting; said one ends of each of said pair of arms also being pivoted to one end of a link, the other end of which is pivoted to said housing.

In an alternative construction, said first moving means is pivotally secured to said mounting at one end and at the other end is pivotally secured to one end of an arm, the other end of which is pivoted to said mounting; said one end of said arm also being pivoted to one end of a link, the other end of which is pivoted to said housing.

The link may be a single plate or a pair of parallel plates. As used herein, the term "moving means" includes any suitable, robust, moving means, e.g. hydraulic ram, rack- and -pinion, jack, linear actuator.

Preferably, said stabiliser is adapted to be vehicle mounted, for use in combination with a vehicle mounted crane.

The stabiliser of the present invention may be used in combination with a fixed mounting or with a mounting which is moveable to any of a range of selected positions along a supporting surface. Most preferably, the mounting comprises a pair of spaced parallel plates with the stabiliser pivotally mounted between the plates. Preferably also, the combination of the mounting and the stabiliser can be slid along the length of a supporting surface (e.g. a vehicle chassis) by moving means. Brief Description of the Drawings

By way of example only, the preferred embodiment of the present invention is described in detail with reference to the accompanying drawings, in which:-

Figure 1 is a side view of the stabiliser of the present invention in the stowed position; Figure 2 is a side view of the stabiliser of the present invention in a first position;

Figure 3 is a side view of the stabiliser of the present invention in a second position; Figure 4 is a side view of the stabiliser of the present invention in a third position; and Figure 5 is a side view of the stabiliser of the present invention in a fourth position.

In the following description of the preferred embodiment, the stabiliser is described with reference to a vehicle mounted stabiliser for use with a vehicle mounted crane. However, it will be appreciated that the stabiliser of the present invention could be mounted on a stationary support, rather than upon a vehicle, if required. Further, vehicle mounted cranes of the type described below usually are operated in pairs, with a crane and its accompanying stabiliser mounted at each end e.g. of a vehicle trailer. The drawings show only a single stabiliser; if the stabiliser is used as one of a pair, the second stabiliser of the pair is simply a mirror image of the first stabiliser.

In the preferred embodiment, all of the moving means are hydraulic rams.

Referring to the drawings, a stabiliser 10 in accordance with the present invention is pivotally mounted on a vehicle mounting 1 1 and includes a housing 12, an extension leg 13 telescopically mounted within the housing 12, and a primary leg 14.

The vehicle mounting 1 1 includes a pair of spaced parallel plates, of which only one, 1 1 a, is visible. The mounting 1 1 provides a heavy duty support capable of supporting the stabiliser 10 between the plates. A crane (not shown) is mounted adjacent the inner surface, (i.e. the surface opposite surface 1 1 a) of the mounting 1 1. The mounting 1 1 is formed with a cutout 15 shaped to fit the profile of the vehicle chassis, so that the mounting 1 1 fits over, and is keyed to, the vehicle chassis. The mounting 1 1 and the adjacent crane mounting may be fixed in position on the vehicle, or may be slidably mounted on the chassis and provided with moving means so that the position of the crane and stabiliser along the vehicle can be adjusted as required. One end of the housing 12 is pivoted to an upper portion of the mounting 1 1 by a pivot 16. As shown in Figures 2 and 3, the housing 12 can be pivoted relative to the mounting 1 1 by means of a moving means in the form of an hydraulic ram 17 one end of which is secured to a pivot 18 on the mounting 1 1 and the other end which is secured to one end of each of a pair of arms 35, by a pivot 34. The other end of each arm 35 is pivoted to the adjacent plate of the mounting 1 1 , by a pivot 36. The pivot 34 also carries a link 37 in the form of a pair of plates, which are arranged one on each side of a bracket 19 secured to the side of the housing 12. The other end of the link 37 is pivoted to the bracket 19 by a pivot 20. Depending upon the strength of the connection required, the link 37 may be a single plate.

A variant arrangement is to pivot the other end of the hydraulic ram 17 directly to pivot 20, but the arrangement shown in the drawings is preferred, because it significantly increases the range of movement of the housing 12 relative to the mounting 1 1 without requiring the use of a bigger ram 17 or a ram with a longer stroke. The larger the ram 17 (or the longer of the stroke), the greater the overall tare weight of the unit.

Another possible variant is to use only a single arm 35 and form the link 37 from a single plate rather than a pair of plates. Obviously, the strength of the arm and the link would have to be increased to compensate for the asymmetrical construction. Other possible variants are to use a single arm 35 but with a pair of plates forming the link 37 or to use a pair of arms 35 but a single plate to form the link 37. By extending the ram 17, the housing 12 can be pivoted between the stowed position shown in Figure 1 , in which the housing 12 is angled back over the vehicle deck with the longitudinal axis of the housing 12 at an acute angle (typically about 45°) to the plane of the vehicle deck, and the extended position shown in Figures 4 and 5, in which the housing 12 is extended away from the mounting 1 1 , outwards from the deck in a plane parallel to, but above, the plane of the deck.

It is a significant advantage of the present invention that the housing 12 and the associated legs can be stowed at an acute angle to the vehicle deck or other supporting surface. In most prior art stabilisers, the stowed position of a stabiliser is close to the vertical, which of course increases the overall height of the unit. The housing 12 is hollow, and can receive telescopically therein the extension leg 13 which can be retracted into the housing 12 as shown in Figures 1 , 4 and 5, or extended out from the housing 12 as shown in Figures 2 and 3, with the longitudinal axis of the extension leg 13 aligned with the longitudinal axis of the housing 12. Movement of the extension leg 13 relative to the housing 12 is by means of a hydraulic ram (not visible) mounted inside the housing 12. The outer end of the first leg 13 is fitted with a foot 21 which may be of any known type, but which is depicted as a pivotally mounted foot pivoted to the end of the first leg by a pivot 22, so that the foot of 21 can adjust to variations of the ground surface and still provide a stable mounting.

The use of the extension leg 13 is optional: ~ some users do not require any leg capable of being positioned as shown in figures 2 and 3, and in that case the extension leg 13 and the foot 21 are simply omitted. The extension leg 13 would not normally be fitted unless it were required, because it increases the overall weight of the unit. However, it should be noted that the ability to move the housing 12 to a position at an acute angle to the vehicle deck means that the extension leg 13 can be used without modification or re-positioning of the housing 12:- when the housing 12 is in the stowed position, it is at the correct angle for using the extension leg 13. The end of the housing 12 remote from the pivot 16 connecting the housing to the mounting 1 1 , carries the pivotally mounted primary leg 14 which is mounted adjacent that end of the housing 12 by a pivot 23. Pivotal movement of the primary leg 14 relative to the housing 12 is by means of an hydraulic ram 24 which is pivotally mounted between brackets 25 on the housing 12 (visible in Figure 5 only) by a pivot 26, and a pivot 27 at one end of the primary leg 14. The brackets 25 extend one on each side of the ram 24 and extend beyond the lower edge of the ram 24, as seen in figure 5; this helps to protect the ram 24 from damage. The free end of the primary leg 14 is fitted with a foot 28 which is a pivotally mounted foot, like the foot 21. The primary leg 14 consists of a first portion 30 and a second portion 31 ; two portions are inclined with their longitudinal axes at an angle of approximately 135°. The first portion 30 is mounted to the housing 12 by the pivot 23 and the end of the first portion adjacent the second portion 31 carries the pivot 27. The above described stabiliser is used as follows:- when the vehicle is in transit and the stabiliser is not required, the extension leg 13 is retracted into the housing 12, the hydraulic ram 17 is retracted to swing the housing 12 back over the vehicle deck, and the hydraulic ram 24 also is retracted, to pivot the second leg 14 to the position shown in Figure 1 , folded back towards the housing, so that the second portion 31 of the second leg 14 lies with its longitudinal axis at a small acute angle to the longitudinal axis of the housing 12.

To move the stabiliser to a conventional stabilising position of the type shown in Figure 2, the hydraulic ram inside the housing 12 is extended to extend the extension leg 13 relative to the housing 12 until the foot 21 rests securely on the ground alongside the vehicle. In this position, the longitudinal axes of the housing 12 and the extension leg 13 are aligned, and at an angle of about 40° to the vertical.

To move the stabiliser to the position of Figure 3, in which the extension leg is in close towards the vehicle, the hydraulic ram 17 is extended to swing the housing 12 and the aligned extension leg 13 further towards the vertical. It will be appreciated that the stabiliser leg positions shown in Figures 2 and 3 are examples only; the exact angle of the leg 13 to the vertical can be varied over a large range, simply by adjusting the extension of the ram 17, with any necessary adjustments of the amount by which the first leg 13 is extended relative to the housing 12, using the hydraulic ram inside the housing 12.

To move the stabiliser to the position of Figure 4, firstly the extension leg 13 is fully retracted into the housing 12 and the hydraulic ram 17 is extended to move the housing 12 until the longitudinal axis of the housing 12 is substantially horizontal and a protective pad 32 on the lower surface of the second portion 31 of the primary leg 14 rests on the top of a trailer (not shown) alongside the vehicle. The foot 28 is pivoted out of the way, as shown in Figure 4. The pad 32 may be adjustable in position, to accommodate different trailer heights. To move the stabiliser to the position of Figure 5, the extension leg 13 is fully retracted into the housing 12, the hydraulic ram 17 is extended to move the housing 12 until the longitudinal axis of the housing 12 substantially horizontal, and the hydraulic ram 24 is extended to swing the primary leg 14 into a position where the longitudinal axis of the second portion 31 of the primary leg 14 is at or close to vertical and the lower surface of the foot 28 rests upon the ground or other supporting surface. In this position, the stabiliser essentially forms a partial arch which can extend over an adjacent vehicle:- the primary leg 14 forms one side of the arch, the housing 12 forms the top of the arch. This position is useful, for example, for a situation where a container to be moved is resting on the ground and needs to be loaded onto a second trailer:- the first vehicle is positioned beside the container, both stabilisers are deployed to the position shown in Figure 5, with the stabilisers one on each side of the container. The container is then raised using the cranes and the second trailer can be backed underneath the arched stabilisers as soon as the container has been raised. The container can then be lowered on to the second trailer. Once the container is loaded, the stabiliser legs are raised and the second trailer is driven away. The stabilisers can then be re-extended if necessary to unload from the original vehicle.

The primary leg 14 may be positioned further away from the mounting 1 1 than is depicted in Figure 5, i.e. with the longitudinal axis of the second portion 31 at an acute angle to the vertical. However, for maximum strength and stability, the second portion 31 should have its longitudinal axis substantially vertical. Another possible variation is to increase the extension of the hydraulic ram 17 to permit the housing 12 to move below the position depicted in Figure 5, i.e. with the longitudinal axis of the housing 12 at an acute angle to the horizontal.

If the stabiliser is required only for a specific application, then one or both of the primary leg 14 and the extension leg 13 may be omitted. As noted above, the extension leg 13 is omitted if a user does not require a leg capable of being positioned as shown in Figures 2 and 3. Conversely, if a user requires only the configuration shown in Figures 2 and 3, then the primary leg 14 may be omitted and the extension leg 13 fitted. Another possibility is to omit both the primary leg 14 and the extension leg 13:- this is a viable option if only the position shown in Figure 4 is required. In this case, the pad 32 would be fitted on the underside of the housing 12 rather than on the primary leg 14.

It will be appreciated that the above described stabiliser is both compact and extremely versatile:- it can be stowed (see Figure 1 ) in a position in which its height above the vehicle deck is minimised, and it can be provided with only the housing 12, or with the housing 12 plus the extension leg 13, or with the housing 12 plus the primary leg 14, or with the housing 12 plus both the extension leg 13 and the primary leg 14.

Claims

Claims 1 . A stabiliser for use in stabilising cranes, wherein the stabiliser includes a housing which is adapted to be pivotally mounted upon a mounting and which is provided with a first moving means adapted to alter the position of the housing relative to the mounting between a first position in which the housing is inclined towards the mounting at an acute angle to the mounting and a second position in which the housing is extended away from the mounting.

2. The stabiliser as claimed in claim 1 , wherein the stabiliser further includes a primary leg pivotally mounted to the housing at a position remote from the pivotal mounting of the housing to the mounting; and a second moving means connected between the primary leg and the housing and adapted to pivot the primary leg relative to the housing between a first position in which said leg is folded back towards said housing, and a second position in which, when the housing is in its second position, the housing and the primary leg respectively form the top and one side of an arch.

3. The stabiliser as claimed in claim 1 , wherein, in the second position of the housing, the housing is substantially horizontal.

4. The stabiliser as claimed in claim 2 wherein, in the second position of the housing, the housing is substantially horizontal, and in the second position of the primary leg, the primary leg is substantially vertical.

5. The stabiliser as claimed in any one of the preceding claims, wherein the stabiliser further includes an extension leg telescopically mounted within the housing, said extension leg being extensible and retractable relative to the housing by a further moving means.

6. The stabiliser as claimed in any one of the preceding claims, wherein said first moving means is pivotally secured to said mounting at one end and at the other end is pivotally secured between one end of each of a pair of arms, the other ends of which are pivoted to said mounting; said one ends of each of said pair of arms also being pivoted to one end of a link, the other end of which is pivoted to said housing.

7. The stabiliser as claimed in claim 6, wherein said link consists of a pair of parallel plates.

8. The stabiliser as claimed in any one of claims 1 -5, wherein said first moving means is pivotally secured to said mounting at one end and at the other end is pivotally secured to one end of an arm, the other end of which is pivoted to said mounting; said one end of said arm also being pivoted to one end of a link, the other end of which is pivoted to said housing.

9. The stabiliser as claimed in claim 8, wherein said link consists of a pair of parallel plates.

10. The stabiliser as claimed in any one of the preceding claims, wherein the mounting is a fixed mounting.

1 1. The stabiliser as claimed in any one of claims 1 -9, wherein the mounting is a movable mounting.

12. The stabiliser as claimed in any one of the preceding claims, wherein the mounting comprises a pair of spaced parallel plates with said housing mounted between said plates.

13. The stabiliser as claimed in any one of the preceding claims, wherein each of said moving means is selected from the group consisting of: hydraulic ram, rack and pinion, jack, linear actuator.