GB2433284A

GB2433284A - Levelling tool

Info

Publication number: GB2433284A
Application number: GB0525382A
Authority: GB
Inventors: Mark John Cutler; Alex Woodfield
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-12-14
Filing date: 2005-12-14
Publication date: 2007-06-20
Anticipated expiration: 2025-12-14
Also published as: GB2433284B; GB0525382D0

Abstract

A levelling tool 10 has an elongate datum member 12 and a scraper member 14, said scraper being attached parallel to the datum member and extending from one end along a part of its length. The lower edge of the scraper is additionally parallel to the longitudinal axis of the datum member and may be bevelled or radiussed. The scraper may be attached to the datum member by releasable means 16,18 with provision, such as a spacer, for adjusting the depth of the scraper. Wheels or rollers may be provided on the datum member. When in use, with the datum member positioned on a guiding surface such as paving slabs, the scraper member is inclined with its lower edge trailing its upper edge. The datum member may contain a spirit level 20.

Description

LEVELLING TOOL

The present invention relates to a levelling tool and in particular to a levelling tool for use in the laying of paving slabs or block paving.

Paving slabs or block paving are conventionally laid on a bed of dry mix concrete or sand. In order to ensure that the slabs or blocks are level, it is necessary to ensure that the bed is level before laying the slabs or blocks.

This may be achieved by laying the bed and levelling it by drawing a straight edge over the surface of the bed. This presents problems where large areas are to be paved, when for example the flat bed may be disturbed as the slabs or blocks are laid.

The present invention provides a laying tool, which will enable the levelling 1 5 of the bed in sections, as the slabs or blocks are laid.

According to one aspect of the present invention, a levelling tool comprises a rectilinear elongate datum member and a scraper member, the scraper member being secured to the datum member in juxtaposed relationship and parallel thereto, the scraper member extending from one end of the datum member along part of the length of the datum member and having a lower edge which is parallel to the a longitudinal axis of the datum member.

With the levelling tool described above, once one row of paving slabs have been laid, the portion of the datum member which extends beyond the scraper member is engaged with the upper surface of the existing row of slabs, with the scraper member extending downwardly below the upper surface of the existing row of slabs. The datum member may then be drawn across the upper surface of the existing row of slabs so that the lower edge of the scraper member will level the bed of dry mix concrete or sand, ready for the next row of slabs.

The depth of the scraper member conforms to the thickness of the slabs being laid, so that the level of the bed will be slightly higher than the lower surface of the existing row of slabs, in order to allow for compaction, when the next row of slabs are laid.

The levelling tool may be designed for a specific thickness of slabs.

Alternatively, the scraper member may be attached to the datum member so that its depth may be adjusted with the lower edge of the scraper member remaining parallel to the datum member.

The length of the scraper member is preferably sufficient to level a bed the width of which is sufficient to lay the next row of slabs. However, when the levelling tool is to be used for block paving the datum member will engage several rows of blocks and the scraper member will be long enough 1 5 to level a bed of sufficient width to lay several rows of blocks.

The datum member may be provided with a spirit level, which may be used to ensure that the first row of slabs or blocks is level and has an appropriate drain off.

An embodiment of the invention is now described, by way of example only, with reference to the accompanying drawings, in which:-Figure 1 shows a perspective view of a levelling tool in accordance with the present invention; and Figure 2 shows a side elevation of the levelling tool in use.

As illustrated in Fig. 1, a levelling tool 10 comprises a datum member 12 and a scraper member 1 4, both the datum member 1 2 and scraper member 1 4 being made of square tubular aluminium section. The scraper member 14 extends about half the length of the datum member 1 2 and is bolted to the datum member 1 2 adjacent one end thereof, by means of a pair of studs 1 6.

The scraper member 14 has a lower edge 24 remote from to the datum member 1 2. The studs 1 6 are secured in suitable manner to the scraper member 14, without extending beyond the edge lower edge 24 thereof. The studs 1 6 extend through apertures in the datum member 1 2 and wing nuts 1 8 engage the studs 1 6, to secure the scraper member 1 4 to the datum member 1 2, so that the lower edge 24 of the scraper member is parallel to the datum member. Alternatively, bolts may be used to secure the scraper member 1 4 to the datum member 1 2, the heads of the bolts being countersunk to provide a smooth surface on the lower edge 24 of the scraper memberl4.

A flush mounted spirit level 20 is provided in the datum member 1 2. Plastic end caps (not shown) are provided to close the ends of the tubular datum 1 5 member 1 2 and scraper member 1 4.

As illustrated in Figure 2, a row of slabs 22 is first laid on a bed 26 of dry mix concrete which will level out any irregularities in the ground level G, in conventional manner. The spirit level 20 on the datum member 1 2 may be used to ensure that the first row of slabs 22 is laid level with an appropriate drain off.

Dry mix concrete is then deposited adjacent the row of slabs 22 to form a bed for the next row of slabs. The portion 1 2a of the datum member 1 2 which extends beyond the scraper member 1 4 is then laid on the upper surface of the existing row of slabs 22, so that the scraper member 14 extends downwardly by the side of the existing row of slabs 22. The levelling tool 10 is then drawn along the existing row of slabs 22 with portion 1 2a of the datum member 1 2 engaging the upper surface of the row, so that the lower edge 24 of the scraper member 1 4 will level the dry mix concrete to form a bed 26 for the next row of slabs 22. Additional dry mix concrete may be deposited in front of the scraper member 14 to fill any depressions.

The level of the bottom edge 24 of the scraper member 14, when the datum member 1 2 engages the upper surface of the existing row of slabs 22, is preferably higher than the bottom surface of the existing row of slabs 22 in order to allow for compaction of the bed 26 as the next row of slabs are laid.

1 0 The depth of the scraper member may be adjusted for different thickness of slab by undoing the wing nuts 1 8 and placing shims between the scraper member 14 and datum member 12.

Other suitable means may be used for securing the scraper member 1 4 to 1 5 the datum member 1 2 and for adjusting the depth of the scraper member 14, so that its lower edge 24 remains parallel to the datum member 12.

Alternatively, the levelling tool may be designed for a specific thickness of slab and no adjustment means provided.

In accordance with a further embodiment of the invention means, for example rollers or wheels, may be provided on portion 1 2a of the datum member 1 2, so that it may be drawn smoothly along the upper surface of the existing row of slabs 22.

Furthermore, the lower edge of the scraper member 14 may be bevelled or radiussed, so that it will compact the dry mix concrete, as it is drawn across to form the bed 26.

Alternatively, the scraper member 14 may be mounted to the datum member 1 2 in a manner such that as the datum member 1 2 is drawn across the upper surface of the existing row of slabs 22, the scraper member 14 will be inclined, the lower edge 24 of the scraper member 14 trailing its upper edge.

Various modifications may be made without departing from the invention.

For example the datum member 1 2 and the scraper member 14 may be made of any suitable material, for example metal, plastics or wood; and be solid of hollow of any suitable section. The datum member 1 2 is however preferably designed so that as it is drawn along the upper surface of the existing row of slabs 22 or blocks, it will maintain the scraper member 1 4 in an appropriate orientation to produce the desired level of the bed 26, upon which the next row of slabs or blocks are to be laid.

While the present invention is particularly intended for levelling a bed for laying slabs or blocks, it may be used for levelling any free flowing materials, relative to a datum surface.

Claims

Claims 1. A levelling tool comprising a rectilinear elongate datum

member and a scraper member, the scraper member being secured to the datum member in juxtaposed relationship and parallel thereto, the scraper member extending from one end of the datum member along part of the length of the datum member and having a lower edge which is parallel to the a longitudinal axis of the datum member.

2. A levelling tool according to claim 1 in which the scraper member is secured to the datum member by releasable fastening means.

3. A levelling tool according to claim 2 in which means is provided for 1 5 adjusting the depth of the scraper member.

4. A levelling tool according to claim 3 in which spacer means are S...

i..., provided on the fastening means, between the datum member and scraper I...

member.

SI S

. .: 20

S

I.....

* S 5. A levelling tool according to any one of the preceding claims in which wheels or rollers are provided on the datum member, for engagement of a .. guiding surface.

* S SI 6. A levelling tool according to any one of the preceding claims in which the lower edge of the scraper member is bevelled or radiussed.

7. A levelling tool according to any one of the preceding claims in which the scraper member is mounted with respect to the datum member such that when the datum member engages a guiding surface, the scraper member is inclined, the lower edge of the scraper member trailing its upper edge.

8. A levelling tool according to any one of the preceding claims in which a spirit level is provided in the datum member.

9. A levelling tool substantially as described herein, with reference to and as shown in figures 1 and 2 of the accompanying drawings. * S. * I I S... S... * S S... SI * * I. * S. *

S..... * S S. * I * SI* *SS* * . * III