Levelling device for screed

Abstract

A levelling device 10 suitable for levelling screed, in which the device comprises a plurality of legs 12 and a sheath 14 supported by the legs. A rod 18 is moveable in the sheath, the rod having a ga

Description

The present invention relates to a levelling device for use in the process of levelling screed or other wet poured construction materials, such as concrete. Screed, or self-levelling screed, is a thin top layer of material poured as a liquid onto a concrete sub-floor, or similar base, to provide a level surface. Levelling devices, which are conventionally tripods and so may be termed screed levelling tripods, may be used to indicate the level of screed material to be poured. A typical screed levelling tripod comprises three legs which supports a sheath. The sheath is screw threaded, and a screw-threaded rod is positioned inside the sheath. The screw threads engage, and the rod is turned so as to adjust the height of the rod relative to the sheath. At the bottom of the rod is a plate, which acts as a marker for the height to which screed should be poured. A user adjusts the height of the rod, and so plate, to the desired height using a laser beam to act as a reference. When the sub-floor is uneven, multiple such tripods can be distributed across the uneven floor, with the plates adjusted so that they are coplanar with each other. However, when screed is poured, the screed can splash, spatter or otherwise contaminate the rod. Once contaminated with screed or other liquid, this can impact the ability to turn the rod. Additionally, in general, turning the rod can be a time-consuming matter. The present invention seeks to provide a solution to these problems. The invention is defined in the claims. The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a view of a first embodiment of a levelling device in accordance with an aspect of the invention; Figure 2 shows an enlarged view of Figure 1; Figure 3 shows a view of the levelling device of Figure 1 in a disassembled state; Figure 4 shows a view of a second embodiment of a levelling device in accordance with an aspect of the invention; and Figure 5 shows a view of a third embodiment of a levelling device. Referring firstly to Figures 1 to 3, there is shown a first embodiment of a levelling device 10 for use with levelling screed. The levelling device comprises three legs 12 which support a sheath 14 or holder. In view of the three legs, the device may be termed a tripod. However, it will be appreciated that more legs may be considered. The legs are preferably equiangularly spaced apart from each other. Each leg extends vertically or substantially vertically upwards before extending inwards towards the sheath. As such, each leg may have an elbow 16 which separates a vertically extending portion from a horizontally extending portion. An exterior surface of each leg at the elbow is preferably curved. The interior surface of the leg at the elbow is preferably straight, and may be, for example, angled at substantially 45 degrees to the vertically extending portion and horizontally extending portion. Each leg is thin or plate like. The height of each leg may be, for example 295 mm. The sheath is preferably substantially tubular, preferably with an interior surface having a cylindrical shape. The exterior surface may be facetted, having the shape of a hexagonal prism for example, which may allow for easier connection with the legs. The sheath receives a rod 18. The sheath and rod are dimensioned and configured so that the rod can slide in the sheath. For example, the interior wall of the sheath may be smooth. The sheath includes an aperture 20 through a side wall thereof, which is preferably screw threaded. The levelling device further com prises a clamping means 22, orclamp, for clam ping the rod in the sheath. Here the clamping means comprises a clamping member or bolt having a screw threaded portion 24, the clamping member configured to extend through the screw-threaded aperture of the sheath and engage a side of the rod. The screw threads of the aperture and clamping member mate and allow the turning of the clamping member in the aperture, moving the clamping member towards and away from the rod. The clamping member has a handle 26forturning the clamping member. The handle is disengageable relative from the screw-threaded portion so that the handle can be turned without turning the screw-threaded portion. For example, the clamping member and handle may have connectors so that, when the handle is pushed forwards on the clamping member, the connectors are engaged or connected, and the handle can turn the screw-threaded portion. When the clamping member is pulled away from the clamping member, the connectors are disengaged or disconnected, and the handle cannot turn the screw-threaded portion. There is preferably a biasing means which biases the handle towards the remainder of the clamping member, so that the handle turns the screw-threaded portion when the handle is not being pushed or pulled relative to the remainder of the clamping member. When the handle is pulled away from the remainder of the clamping member against the biasing means, the handle disconnects from the remainder of the clamping member, and the handle can be freely turned or rotated. The rod is preferably cylindrical and has first and second ends. At the first end of the rod is a plate 28 which defines a gauge surface at a lower side of the plate. The gauge surface is flat or substantially flat. The plate in use extends in a horizontal or substantially horizontal direction. The plate is preferably circular or discshaped, although it will be appreciated that other shapes may be considered. An upper surface of the plate may also be flat and sufficiently wide so as to support a reference marker thereon when determining the correct position of the plate. At a second end of the sheath is a cap 30, which creates a general widening of the rod so that it cannot fit through the sheath. The cap is removeable which allows for the rod to pass through the sheath. For safety purposes, the cap is preferably formed from a soft material such as plastic or an elastomeric material, for example rubber, and may be rounded. The cap may have a bright colour, such as green or red, so as to be easily visible. In use, the handle in rotated so that the clamping member is retracted, and a distal end of the clamping member does not engage the rod. The rod can then be moved up or down relative to the sheath until the gauge surface of the plate is at the correct height, which may be determined with laser referencing. The handle can then be rotated so that the distal end of clamping member engages and clamps the rod against the opposite interior side of the sheath. As such, the rod is fixed, locked or clamped in the correct position. If the handle is facing downwards or outwards after tightening, for exam pie being at a 6 o’clock position, the handle can be pulled relative to the remainder of the clamping member to allow it to be repositioned without turning the screw-threaded portion. This may be conveniently done by placing a thumb on a central portion 32 of the clamping memberwhich extends through the handle, and then pulling and rotating the handle with one or more fingers to the correct position. To disassemble the levelling device for cleaning, the clamping member is fully rotated so that it is removed entirely from the sheath, and the cap of the rod can be removed, so that the rod can pass through the sheath. Optionally, the device may have a welded construction, and may be formed from stainless steel or mild steel. Referring now to Figure 4, there is shown a second embodiment of a levelling device which may be similar or identical to the first embodiment, except having differing dimensions. For example, being smaller; the first embodiment having a leg height of 295 mm whilst the second embodiment has a leg height of 195 mm. Referring now to Figure 5, there is shown a third embodiment of a levelling device which is similar or identical to the first embodiment, except having a screw-threaded rod and screw-threaded sheath. The third embodiment has a leg height of 295 mm. The words ‘com prises / comprising’ and the words ‘having / including’ when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in 5 any suitable sub-combination. The embodiments described above are provided by way of examples only, and various other modificationswill be apparent to persons skilled in the field without departing from the scope of the invention as defined herein.

Claims

1. A levelling device for levelling screed, the device comprising:a plurality of legs;a sheath supported by the legs;a rod moveable in the sheath, the rod having a gauge surface at or adjacent to a first end thereof for indicating an intended level of screed;a clamping means for releasably clamping the rod in the sheath.

2. A levelling device as claimed in claim 1, wherein the clamping means comprises a clamping member having a screw threaded portion, the clamping member configured to project through a side wall of the sheath and engage a side of the rod for clamping the rod in position.

3. A levelling device as claimed in claim 1 or claim 2, wherein the clamping member includes a handle for turning the clamping member.

4. A levelling device as claimed in claim 3, wherein the handle is disengageable relative from the screw-threaded portion so that the handle can be turned without turning the screw-threaded portion.

5. A levelling device as claimed in claim 4, wherein the clamping member includes a biasing member for biasing the handle into engagement relative to the screw-threaded portion.

6. A levelling device as claimed in any one of the preceding claims, wherein the gauge surface is defined by an in use lower surface of a plate at or adjacent to the first end.

7. A levelling device as claimed in any one of the preceding claims, wherein the levelling device has three legs, such that the device is a tripod.

8. A levelling device as claimed in any one of the preceding claims, wherein the rod comprises a removeable cap at or adjacent to a second end thereof.

9. A levelling device as claimed in claim 8, wherein the removeable cap comprises a bright colour.

10. A levelling device as claimed in any one of the preceding claims, wherein each leg comprises an in use vertically extending portion, an in use horizontally extending portion, and an elbow therebetween, wherein an interior facing surface of the elbow is straight.IntellectualPropertyOfficeApplication GB2403961.2Search report under Section 17 of the Patents Act 1977Date search completed: 11 September 2025Claims searched: 1-10International classificationSubclass and subgroup Valid from E04F21 / 24 01 / 01 / 2006 E04G21 / 10 01 / 01 / 2006 G01B11 / 06 01 / 01 / 2006Field of searchWorldwide search of patent documents classified in the following areas of the IPC:E04G, E04F, G01BDatabases used in the preparation of this search report:SEARCH-PATENTDocuments considered to be relevantPatent literatureCategory Relevant Document of relevanceclaimsX 1-2, 3-4, 6 7, 8-9, 10 DE 2827521 A1 (WESSELY), Figures 1-4 and page 6 paragraph 2 showing a levelling device specifically for poured screed floors comprising a plurality of legs 2, 3, 4; a sheath 1 supporting the legs; a clamping means (screw clamp 6); in which the rod 5 features a scale with measurement marking (see description, para 2, page 6) and gauge surface 7. X 1, 3, 7, 8, 9 EP 0816745 B1 (MELCHIOR), See Figure and paragraph [009], screed height levelling stand showing plurality of legs 5, 7; sheath (holding device 8); clamping means 16, 17 [paragraph [009] describing eccentric locking mechanism (or spreading spring) serving clamp the gauge rod surface 15 X 1,6-7, 8-9 FR 2971277 A1 (ALKAN), Figures 1a, 1c, 2, 3a-3b showing screed level tripod with legs, sheath (Fig. 3), rod with gauge surface (horizontal end plate) and clamping means (Figure 1c). X 1-2, 6-7 US 4891888 A (MARIA DE BREE et al), See Figs 4&5 especially, showing levelling device for screed floor levelling, legs 103, sheath 101 supported by legs, rod 111 with gauge surface 118 X 1,6-8, 9 DE 20017303 U1 (ECKERT), See Figs 1-3 showing floor levelling device with tripod legs 7 and a sheath 4 (rod guide) with rod 3 held by clamp 5, rod presenting gauge surface plate 9 at one end and bush cap 1 at the other end. X 1-3, 6-7 FR 2904996 A1 (BAUDRY), See Figs 1-2 showing floor levelling device with tripod legs 2 and a sheath 4 (rod guide) with rod 3 held by screw threaded clamp with knurled handle, rod presenting gauge surface plate 7 X 1, 3, 4, 7 CN 211286689 U (CHEN et al), See Figs 1-3 showing concrete floor levelling device with legs 3, rod 2, sheath 8 (Fig 3), measuring rod 2 with scale, height locking screw clamp 4; gauge surface of rod being the lowermost end in use.X 1,6-9 EP 4071319 A1 (SPECIAL BUILDINGS SRL), See screed level gauge in Figs 3 and 4 and paragraphs [0076-0077] describing the spring clamping means 30 acting to releasably clamp the rod 2 in position within the sheath (tube 11), with removable cap 21 on the rod, gauge surface 20. X 1-3, 6-7 WO 2017146380 A1 (JEON et al), see Figs 1-5 showing levelling apparatus 100 with legs 13, rod 20 with gauging surface 23, sheath 11 for receiving rod, handle for activating height adjustment. Non-patent literature Category Relevant claims Document of relevanceCategories Letter or symbol Description X Document indicating lack of novelty or inventive step. Y Document indicating lack of inventive step, if combined with another document of the same category. & Member of the same patent family. A Document indicating technological background. P Document published on or after the priority date but before the filing date of the present application. E Earlier application published on or after the filing date of the present application.

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