GB2436347A

GB2436347A - Levelling means

Info

Publication number: GB2436347A
Application number: GB0704788A
Authority: GB
Inventors: Ian Walker
Original assignee: WALKER PROJECTS Ltd
Current assignee: WALKER PROJECTS Ltd
Priority date: 2006-03-21
Filing date: 2007-03-13
Publication date: 2007-09-26
Also published as: GB0605660D0; GB0704788D0

Abstract

Levelling means 12 are provided for allowing the levelling of an article or part of an article to be adjusted. The levelling means includes engagement means 32 for engaging at least part of an article to be levelled in use and height adjustment means 14 for allowing adjustment of the location and/or height of the article part with respect to the levelling means. Preferably the height adjustment means includes first and second members (38, 39 Fig 2) which are capable of relative sliding movement to allow adjustment of the height of the article part. The first and second members may have an engagement surface (40, 46 Fig 2) for engagement with the other member and said engagement surfaces are capable of relative movement. Preferably the engagement surface of at least one of the members is tapered and / or angled. The invention may be used for articles such as ladders, worktables, jigs or the like.

Description

1 2436347 Levelling Means This invention relates to levelling means and

to a system for allowing an article or part of an article to be levelled with respect to a required surface.

Although the following description refers almost exclusively to a levelling means and system for levelling and stabilising a ladder, it will be appreciated by persons skilled in the art that the present invention can be used to level any article or part of an article as required. The invention is particularly useful for articles which may be moved to different locations during their use and require levelling in each of these different locations, such as levelling means for a workmate, jig and/or the like.

If the base struts of a ladder are located on uneven or sloping ground, the struts of the ladder may not be level and the ladder is thus potentially unstable and could fall over. For example, a 20mm difference in the level of the base struts of a 300mm wide ladder can result in the side of the ladder sloping relative to a vertical axis by approximately 4 degrees, which is sufficient to topple a ladder over even without a user being on the ladder.

Conventional levelling devices typically require drilling of the ladder to attach the devices thereto or require complicated fixing or operation means.

It is therefore an aim of the present invention to provide levelling means for allowing the level of an article or part of an article to be levelled with respect to a required surface which is simple and easy to use.

It is a further aim of the present invention to provide a levelling system.

It is a yet further aim of the present invention to provide ladder levelling means.

It is a yet further aim of the present invention to provide a method of using levelling means.

According to a first aspect of the present invention there is provided levelling means for allowing the levelling of an article or part of an article to be adjusted, said levelling means including engagement means for engaging at least part of an article to be levelled in use and height adjustment means for allowing adjustment of the location and/or height of the article part with respect to the levelling means.

Preferably the levelling means includes a housing with at least a recess or aperture defined therein, the article part being located through or in an opening of said recess or said aperture in use.

The recess or aperture can form the engagement means or can be separate thereto.

Further preferably the levelling means includes a housing in the form of a sleeve member with a recess or channel defined therein. The article part is located in or through a first open end in use and preferably the article part sits in said recess/channel in use. The opposite or second end of said sleeve member can be located directly or indirectly on a surface on which the article or article part is to be levelled/located. The recess or channel can form the engagement means or can be separate thereto.

Preferably the height adjustment means includes at least first and second members which are capable of relative movement to allow adjustment of the height and/or location of the article part. Each member has an engagement surface for engaging with the surface of the other member. The engagement surfaces are preferably slidably movable relative to each other.

Preferably the engagement surface of at least one of the first members is tapered and/or angled, such that movement of the other member relative thereto causes a change in vertical height of the other member.

In one embodiment both the engaging surfaces of said first and second member are tapered and/or angled. The taper and/or angle of each member is typically opposite to the other member when engaged.

Preferably at least a part of the members, and further preferably the second member, is movable within the recess or channel of the housing and arranged such that movement of said member causes movement of an article part located in said recess in use.

Thus, a change in height of said member with respect to the housing causes a change in height of an article part with respect to the housing.

In one embodiment the first member is substantially fixed with respect to the housing in use.

In one embodiment at least part of one or the top member forms a base on which the article part is located in use.

In an alternative embodiment a location portion forms the base of the recess of the housing and said location portion is located between at least a part of one of said members and said article part in use. The location portion and article part typically moves on movement of the member. The movement is preferably in a substantially vertical direction within the housing.

Preferably gripping means ate associated with said one or more engaging surfaces to prevent slipping of the surfaces of said first and second members when moved to a required position.

The gripping means can include any or any combination of one or more teeth, high friction surface, protrusions, steps, inter-engaging members and/or the like.

Preferably one or the first member is substantially fixed with respect to said housing when said housing is assembled in use.

The other member is preferably movable relative thereto.

In one embodiment the engagement means for engaging the levelling means to the article part includes resilient biasing means, which allows an article part to move with respect to the housing whilst maintaining engagement between said housing and said article part.

Preferably the resilient means includes a spring, sprung material, elastic, rubber and/or the like.

The engagement means typically includes a first part for engaging with the article and a second part for engaging with the levelling means or housing of the levelling means. The first and/or second parts can be detachably attached to the levelling means and/or article.

Preferably user actuation means are associated with the height adjustment means to allow relative movement of the members forming the height adjustment means.

The user actuation means can protrude from the housing to allow actuation of the same to actuate movement of the second member.

Preferably a slot is defined in the housing or sleeve member to allow the user actuation means to be slidably mounted therein.

In one embodiment the user actuation means includes a part of one of the members which protrudes from the housing to allow movement by a user.

In one embodiment a levelling system is provided for an article, said levelling system including two or more levelling means, each levelling means associated with a different part of an article.

According to a second aspect of the present invention there is provided a levelling system for an article, said levelling system including two or more levelling means, the levelling means allowing the levelling of part of the article and each levelling means associated with a different part of the article, the levelling means including engagement means for engaging said article part in use and at least one of said levelling means including height adjustment means for allowing adjustment of the location and/or height of the article part with respect to said levelling means.

Jn one embodiment the levelling system includes first levelling means having height adjustment means associated therewith and second levelling means, and wherein the height of the second levelling means with respect to the article being levelled is substantially fixed when said second levelling means is attached to said article.

Preferably the levelling means is used on an article including one or more struts, feet or protruding members to allow engagement with the levelling means, such as for example a ladder, work mate, jig and/or the like.

Preferably the levelling means is detachably attached to the article.

According to a second aspect of the present invention there is provided ladder levelling means.

According to further independent aspects of the present invention there is provided a levelling system for an article; and a kit of parts for forming a levelling system.

According to a further aspect of the present invention there is provided a method of using levelling means for allowing the levelling of an article or part of an article to be adjusted, said levelling means including engagement means for engaging at least part of an article to be levelled in use and height adjustment means and wherein said method includes the step of adjusting said height adjustment means to adjust the location and/or height of the article part with respect to the levelling means.

An embodiment of the present invention will now be described with reference to the accompanying figures, wherein: Figure 1 is a perspective view of a ladder levelling system according to an embodiment of the present invention; Figure 2 is an exploded view of the ladder levelling system in figure 1; and Figures 3a-3d each show front and side views of the ladder levelling system when used on different surface levels.

Referring firstly to figures 1 and 2, there is illustrated a ladder levelling system 2 for allowing the level of a ladder 4 to be adjusted when located on uneven ground in use. More particularly, the levelling system allows the height of a longitudinal strut 6 of ladder 4 to be adjusted with respect to an opposite longitudinal strut 8 of the ladder and/or a ground surface on which the levelling system and ladder is placed. The ladder 4 is of a conventional type having a plurality of substantially parallel rungs 10 engaged between upright struts 6, 8 and provided substantially transversally and/or perpendicularly to said upright struts.

The levelling system 2 includes levelling means 12 with height adjustment means 14 and levelling means 16 without height adjustment means.

Levelling means 12 includes a housing in the form of a sleeve member 18 having a first open end 20 at a top thereof, and a second open end 22 provided at a base thereof. A channel is defined through sleeve member 18. An elongate slot 24 is provided longitudinally of sleeve member 18 in a front end wall 26 thereof.

A protruding pin 28 is provided on an inwardly facing exterior surface of side wall 30 to allow engagement with engagement means, which in this example are in the form of a Connection strap 32. Pin 28 could be provided at any suitable location on the sleeve member 18.

Connection strap 32 includes a first engaging part at an end thereof in the form of ring 34 which engages with rung 10. A second engaging part is provided at an opposite end thereof in the form of ring 36 which engages with pin 28 in use. The elongate body portion of strap 32 is typically formed from resilient biasing material, such as rubber, to allow the distance between sleeve member 18 and rung 10 to be adjusted whilst maintaining/biasing engagement of the sleeve member 18 to strut 6.

Height adjustment means 14 includes a first fixed ramp member 38 and a second movable ramp member 39 which is movable relative to fixed member 38. The two ramp members are at least partially located in sleeve 18 when assembled.

Fixed ramp member 38 has a narrowing taper or downward sloped engagement surface 40 from rear end 42 to front end 44.

The ramp member 38 is located in sleeve member 18 such that the engagement surface slope is provided transversally to the longitudinal axis of sleeve member 18 (parallel to side wall 30) and engagement surface 40 slopes downwardly towards slot 24.

Movable ramp member 39 has a narrowing taper or downward sloped engagement surface 46 in the opposite direction to engagement surface 40 on ramp member 38. Thus, ramp member 39 has a narrowing taper from front end 50 to rear end 52. More particularly, ramp member 39 has a top surface 48 and the engagement surface 46 is provided on a lower or base surface thereof. Stop means in the form of edges 54, 56 are provided at either end of engagement surface 40 to limit movement of ramp member 39 with respect to ramp member 38.

When assembled, engagement surface 40 of ramp member 38 engages with engagement surface 46 of ramp member 39 and engagement surface 46 is slidably movable with respect to engagement surface 40. The ramp member 39 has dimensions such that the taller end 50 protrudes outwardly of slot 24 when assembled in sleeve member 18. As such, end 50 acts as a user actuation portion to allow a user to move ramp member 39 to a required position with respect to ramp member 38. In addition, a further slot (not shown) is defined in rear wall 58 of sleeve member 18 substantially opposite to slot 24. When end 50 of ramp member 39 is pushed through slot 24, the shorter opposite end 52 of ramp member 39 typically protrudes through the opposite slot in rear wall 58.

As ramp member 39 is moved relative to ramp member 38, so the height of the top surface 48 of ramp 39 can be adjusted with respect to sleeve member 18.

In order to prevent engagement surface 40 slipping with respect to engagement surface 46 when the ramp members have been moved to a required position, a plurality of teeth 60, 62 are provided on engagement surfaces 40, 46 respectively. Teeth 60, 62 are arranged transversally across the engagement surface to provide a plurality of steps and the teeth/steps of ramp member 38, engage with complementary shaped teeth/steps of ramp member 39. More particularly, each tooth or step is angled at an acute angle to the horizontal to prevent accidental sliding of the teeth over each other when moved to a required position. Thus, each tooth on lower ramp 38 slopes downwardly or towards the base of the ramp from its free edge. Each tooth on upper ramp 39 slopes upwardly or towards the top of the ramp from its free edge. The teeth can be disengaged when sufficient force is applied to ramp 39 by a user, thereby allowing the height of the ramps relative to each other to be adjusted.

On assembly of the sleeve member 18, a support foot 64 is located in open end 22 to close said open end and provide a base for sleeve member 18 for engagement with a floor surface on which the ladder is to be levelled with. The support foot 64 typically provides a high level of friction between the ladder and surface to prevent slipping of the ladder in use. The top surface 66 of support 64 is substantially planar and horizontal and the base of fixed ramp 38 is located thereon. Movable upper ramp 39 is then located over lower ramp 38 and a support block 68 is located on top surface 48 of ramp 39. Support block 68 has a recess 70 defined therein for the location of end 72 of ladder strut 6. However, it is noted that intermediate support block 68 is optional and ladder strut 6 could be located directly on top surface 48 of upper ramp 39.

Levelling means 16 includes a sleeve member 74 having a first open end 76, a second open end 78 and a channel provided between said first and second open ends. A support foot 80 is located in open end 78 and provides a base for sleeve member 16 for engagement with a floor surface on which the ladder is to be levelled with. A support block 82 is located in sleeve member 16 on top of support foot 80 to allow the position of end 84 of ladder strut 8 to be moved between raised or lowered positions with respect to the sleeve member 74. The support block is optional in levelling means 16. No other height adjustment mechanism is provided in levelling means 16 in this example.

A connection strap 32 engages sleeve member 74 to strut 10 in a manner similar to that described with sleeve member 12 previously.

In use of the device, a user fits sleeve members 18 and 74 over the free base ends 72, 84 of the ladder struts by locating said ends through open ends 20, 76 of said sleeve members and engaging ring 36 of connection strap 32 to pins 28 provided on the inner surfaces of said sleeve members. A user then places the support feet 64, 80 onto the ground surface on which the ladder is to be used. If the struts of the ladder are not level, the user pushes end 50 of ramp 39 inwardly of slot 24 to increase the height of strut 6 relative to sleeve member 18 or pushes end 52 towards slot 24 to decrease the height of strut 6 relative to sleeve member 18. Application of sufficient force to ramp 39 causes engagement surface 46 to move relative to engagement surface 40 of ramp 38, thereby adjusting the height between the base and top of the ramps accordingly.

Referring to figures 3a-3d, it can be seen that when ladders 4 are located on a floor surface 102 which slopes upwardly towards strut 6, upper ramp 39 can be moved such that end 50 thereof is in an extended position protruding outwardly of front slot 24, thereby lowering the height of strut 6 with respect to strut 8 to level the ladder.

In figure 3b, the floor surface 102 is fairly level and therefore end 50 is in a retracted position with respect to slot 24, such that end 52 protrudes from the opposite or rear slot. The relative height of the ramps is therefore at their lowest and the height of strut 6 is substantially the same as the height of strut 8.

In figures 3a and 3b, the end of ladder strut 6 rests directly on top of ramp 39. In figures 3c and 3d, the end of ladder strut 6 rests on support block 68 and thus strut 6 is raised in height by the support block and end 50 of ramp 39 being in its most extended position.

In figure 3d, the floor surface 102 slopes downwardly towards strut 6 and end 50 is in its most retracted position with respect to slot 24.

It will be appreciated that both ladder struts can have sleeve members with or without height adjustment means associated therewith. Alternatively, only one ladder strut could have a sleeve member associated therewith and this sleeve member could have height adjustment means associated with or not with the sleeve member. Thus, a plurality of different combinations of levelling means can be provided for use with a ladder as required.

As the height of the ladder struts with respect to the base of the sleeve members is adjusted, the connection strap expands and retracts to maintain engagement between the ladder and the levelling means during this movement.

The connection strap can be fixedly attached to the ladder and only the sleeve member engagement portion need be detachably attached. Alternatively, both engagement portions of the connection strap can be detachably attached to the ladder.

The levelling means of the present invention can be formed in any suitable size, shape, design and/or material and can be fitted to any size and/or type of ladder as required.

The invention can be designed to work over any level of surface unevenness or slope but in a preferred embodiment, the levelling means are provided to work on ground which has level discrepancy of approximately 25mm or less.

The above described embodiment allows a ladder to be levelled with respect to a floor surface on which it is to be used both quickly and easily, thus ensuring the ladder is stable before use.

In addition, the ladder does not require any drilling or complicated fixing steps to allow the levelling means to be located with the ladder in use.

Claims

Claims:- 1. Levelling means for allowing the levelling of an article or

part of an article to be adjusted, said levelling means including engagement means for engaging at least part of an article to be levelled in use and height adjustment means for allowing adjustment of the location and/or height of the article part with respect to the levelling means.

2. Levelling means according to claim I wherein the levelling means includes a housing with at least one recess or aperture defined therein, the article part being located through or in an opening of said recess or aperture in use.

3. Levelling means according to claim 1 wherein the levelling means includes a housing in the form of a sleeve member with a recess or channel defined therein, the article part being located in or through a first open end of said recess or channel in use.

4. Levelling means according to claim 3 wherein a second or opposite end of the housing is located directly or indirectly on a surface on which the article or article part is to be levelled relative to or located on in use.

5. Levelling means according to claim I wherein the height adjustment means includes at least first and second members.

6. Levelling means according to claim 5 wherein the at least first and second members are capable of relative sliding movement to allow adjustment of the height of the article part.

7. evelli1g meanS cording to claim 5 wherein each of the first and second members has an engageme1t surface for engagemt with the other member and said engagCmt surfaces are capable of relative movement.

8. evel1iflg means according to claim 7 wherein the engagement surface of at least one of the members is tapered and/or angled, such that movement of the engagement surface of the other member relative tO said tapered and/or angled engagement surface causes a change in vertical height of the other member.

9. evel1jfl means according to claim 8 wherein both of the first and second members have tapered and/or angled engagement surfaces.

10. Levelling means according to claim 9 wherein the taper and/or angle of the first member is substantially opposite to the taper and/or angle of the second member.

11. Levelling means according to claim 7 wherein gripping means are associated with the engagement surface of the first and/or second members to prevent slipping of the surfaces relative to each other when moved to a required positiOfl in USC.

12. Levelling means according to claim ii wherein the gripping means includes any or any combiflatb01 of one or more teeth, high friction surface, protruSi0'5 steps or members.

13. Levelling means according to claim 5 wherein the first member is substantially fixedly located in the housing in use and the second member is movable relative to the first member.

14. Levelling means according to claim 5 wherein the article part is located directly on a part of one of the members and movement of said member moves the article part.

15. Levelling means according to claim 5 wherein one or more location portions are provided between a part of one of the members and the article part, the article part being located in the location portion in use.

16. Levelling means according to claim 5 wherein at least one slot is defined in the housing and at least part of one of the members protrudes from the slot in use.

17. Levelling means according to claim 1 wherein the engagement means for engaging the levelling means to an article part includes resilient biasing means.

18. Levelling means according to claim 17 wherein the resilient biasing means include a spring, sprung material, elastic and/or rubber material.

19. Levelling means according to claim 17 wherein the engagement means includes a first part for engaging with a part of the article and a second part for engaging with the levelling means.

20. Levelling means according to claim 19 wherein the first and/or second parts of the engagement means are detachably attached to the levelling means and/or article.

21. Levelling means according to claim I wherein user actuation means are associated with the height adjustment means for allowing relative movement of at least first and second members forming the height adjustment means.

22. Levelling means according to claim 21 wherein the user actuation means protrude from a slot defined in the housing of the levelling means.

23. Levelling means according to any preceding claim wherein the user actuation means forms part of one of the first and second members.

24. Levelling means according to claim 5 wherein stop means are associated with one of said first and/or second members to limit movement of the members relative to each other in use.

25. Levelling means according to claim I wherein the article includes one or more struts, feet or protruding members to allow engagement with the levelling means.

26. Ladder levelling means substantially as described in claim 1 27. A levelling system for an article, said levelling system including two or more levelling means, the levelling means allowing the levelling of part of the article and each levelling means associated with a different part of the article, the levelling means including engagement means for engaging said article part in use and at least one of said levelling means including height adjustment means for allowing adjustment of the location and/or height of the article part with respect to said levelling means.

28. A method of using levelling means for allowing the levelling of an article or part of an article to be adjusted, said levelling means including engagement means for engaging at least part of an article to be levelled in use and height adjustment means and wherein said method includes the step of adjusting said height adjustment means to adjust the location and/or height of the article part with respect to the levelling means.