GB2259938A - Spreader for adhesive - Google Patents

Abstract

A spreader for tile adhesive and the like and having a notched edge 14a includes an obturator 16 movable with respect to the edge to permit adjustment of the notch size. The obturator may have a straight or wavy edge and be guided for movement with respect to the notched edge. The spreader may include means to hold the obturator in one of a number of alternative positions. These means may be wing nuts, as shown, or snap-action formations in a groove (Fig. 6, not shown). The obturator may be L shaped and move diagonally to allow the toothing on two perpendicular edges to be adjusted. <IMAGE>

Description

SPREADER FOR ADHESIVE This invention relates to spreaders and trowels for adhesives and the like.

Spreaders are used for example by tile fixers to apply a layer of adhesive to a surface prior to the fixing of tiles. In this specification the word tile is intended to include a wide range of floor and wall coverings fixed by adhesive including, but not limited to, thermoplastic tiles, ceramic tiles, terrazzo, stone cladding and clay or concrete slabs. The term adhesive, as used herein, includes spreadable materials for fixing such tiles including but not limited to synthetic adhesives, mortar, and tile cement.

The spreaders are notched so that the adhesive is laid in uniform lines of a consistent volume. Spreading adhesive in lines rather than as a thin layer has several advantages.

Firstly the volume of adhesive for fixing an area of tiles is minimised. Secondly the space between the lines permits the adhesive to spread under pressure, so allowing the tile fixer to level a tile with its neighbours. Thirdly, the ability of the tile to spread allows the tile fixer to compensate for an uneven substrate by laying adhesive in lines of an appropriate depth and width.

The variety of substrates, adhesives and tiles has led to the use of a variety of spreaders each having a different arrangement and size of notches. Typically a professional tile fixer might use up to eight trowels having different notched edges to suit different types of tile and substrate; even so the perfect notch arrangement is seldom obtainable.

Inevitably the requirement for six to eight trowels often means that the required trowel cannot be found when it is needed.

It has been proposed to provide interchangeable spreaders for attachment to trowels but this suffers the disadvantage that the individual spreaders also become mislaid or lost. Furthermore it is very time consuming to change spreaders during a tile laying operation, for example when crossing from one type of substrate to another, or to compensate for a gradual change in substrate condition.

The present invention provides a solution to the aforementioned problem by providing a spreader for tile adhesive and the like, the spreader comprising a base having an edge with notches therein and an obturator adjacent said base and movable relative thereto to vary the effective size of said notches. Preferably the base is larger than said obturator. In a preferred embodiment the base comprises a rectangular sheet steel float, and the obturator comprises a sheet steel member on the reverse side of the float.

Alternatively the spreader may be a plastics moulding.

In a preferred embodiment said notches are substantially identical, rectangular and equally spaced along said edge, each notch being approximately twice as deep as it is wide, and said obturator is adapted to overlie said notches on one side of said spreader.

The obturator may have a straight edge and be adapted for movement orthogonal to the spreading edge.

Preferably the spreader includes guide means to ensure orthogonal movement of said obturator with respect to the spreading edge, thereby to ensure that the depth of each notch is identical. The spreader may include locking means to hold the obturator in a desired position.

In one embodiment the spreader comprises a notched metal trowel having a flat rectangular obturator on the upper side thereof, said trowel having upstanding studs adjacent opposite ends thereof and said obturator having guiding slots perpendicular to the obturating edge and engageable over said studs. In a preferred embodiment, the studs are threaded to receive respective locknuts for the obturator.

Such a tool would be intended for use by a professional tile fixer and be capable of repeated use and adjustment.

Such a tool has the advantage of an infinite range of adjustment, thus permitting a professional tile fixer to determine the precise volume of adhesive in accordance with the substrate and tile.

In another embodiment the spreader comprises a disposable plastics assembly having a notched edge and an obturator attachable thereto at spaced locations. The obturator may for example be releasably attachable in a plurality of positions by snap-lock means. Such a disposable spreader is intended for supply with a tub of adhesive and for a single use, instructions being given as to the correct depth of notch appropriate for typical tiles and substrates.

The obturator may move other than at right-angles to the spreading edge For example an 'L' shaped obturator may be arranged to move at 450 to the main spreading edge thus simultaneously adjusting the notch depth on both a long and short side of a spreader. Alternatively the obturator may have a toothed edged, such as a triangular or sinusoidal waveform, and he adapted to move parallel to the spreading edge.

Other features will be apparent from the following description of preferred embodiments shown by way of example only with reference to the accompanying drawings in which: Fig. 1 is a side elevation of a conventional tile fixers trowel; Fig. 2 is a plan of the trowel of Fig. 1; Fig. 3 is a plan of a trowel similar to that of Fig.

2 but modified in accordance with the invention; Fig. 4 is a schematic plan of an alternative embodiment of the invention; Fig. 5 is a partial schematic plan of another embodiment of the invention; and Fig. 6 is a plan of a disposable spreader in accordance with the invention.

Figs. 1 and 2 illustrate a conventional tile fixers trowel 10 comprising a flat sheet steel base 11 having upstanding handle supports 12 welded thereto and a generally cylindrical wooden handle 13; the base is typically 250 mm long and 115 mm wide.

The trowel has a plurality of rectangular notches 14 along one short and one long side; the depth and width of the notches determine the volume of adhesive spread on a substrate. Typically a professional tile fixer will have six to eight trowels with different notch sizes and spacing; the notches may be square or rounded at their inner periphery.

Fig. 3 illustrates the trowel of Fig. 1 modified in accordance with the invention. The trowel base 11a has two upstanding screw-threaded studs 15 welded thereto, and the notches 14a on the long side are deeper than normal. In the example illustrated, the notches 14a are approximately twice as deep as those illustrated in Fig. 2. A rectangular plate 16 having slots 17 perpendicular to the long edge and aligned with studs 15 partially covers the notches 14a. The effective depth of notches 14a may be varied by moving the plate towards and away from the long edge of the base Ila as indicated by arrow 18; wing nuts 19 hold the plate in any desired position. The tile fixer may thus adjust the depth of notch to suit the particular site conditions.

Fig. 4 indicates a variant of Fig. 3 in which an shaped plate 21 is constrained to move at 450 with respect to a trowel base 22 by any suitable means; the plate 21 may be for example guided in the same manner as the plate 16 but within the slots arranged in the direction of travel. The handle has been omitted from Fig. 4 for reasons of clarity.

The plate 21 is shown in a first position A and a second position B.

Fig. 5 illustrates an alternative edge profile for the base and in which triangular notches 23 are obscured to any desired depth by a straight edged plate 24. Alternatively the plate 24 could also have triangular notches in the edge, and be moved parallel to the long edge of the base to give triangular spreading notches of increasing size.

Fig. 6 illustrates a disposable spreader 31, typically of plastics material, and having no handle. The spreader is grasped along the plain edge 32.

Cylindrical pegs 33 project from one side of the base 34 and engage in slots 35 of a straight edged plate 36. As illustrated, each slot 35 comprises a long arm at right angles to the spreading edge, and three aligned short arms parallel to the spreading edge. The junctions between the long and short arms are narrowed as illustrated. In use the plate 36 is placed over the pegs 34 and may be moved so that a pair of short arms may be snapped over the pegs to retain the plate in a desired position. The user can choose an alternative position by sliding the plate 36 sideways until the pegs 34 snap into the long slots, moving the plate forward or backwards with respect to the base 34, and snapping the plate sideways into an alternative pair of short arms of the slots. The pegs may have an enlarged head to prevent disengagement of the plate; a keyhole starter slot may be provided in such case.

Other arrangements of holding the base and plate together are possible; it is preferable that the component parts be capable of being dismantled for cleaning.

Claims (11)

CLAIMS:

1. A spreader for tile adhesive and the like, the spreader having a notched edge and an obturator adjacent said notched edge and movable relative thereto to vary the effective size of said notches.

2. A spreader according to Claim 1 wherein said obturator has a straight edge and is adapted for movement orthogonal to said notched edge.

3. A spreader according to Claim 1 wherein said obturator has a toothed edge and is adapted for movement transversely of said notched edge.

4. A spreader according to any preceding Claim and further including detent means to hold said obturator in one of a plurality of alternative positions.

5. A spreader according to Claim 4 wherein said detent means comprise at least one male member of one of said spreader and obturator, a female member of the other of said spreader and obturator engageable with said male member, and means biasing said male and female members into engagement at said alternative locations.

6. A spreader according to Claim 5 wherein said male member comprises an upstanding peg of said spreader and said female member comprises a channel of said obturator.

7. A spreader according to Claim 5 or Claim 6 and having detent means adjacent opposite ends of said notched edge.

8. A spreader according to any preceding Claim and further including locking means to retain said obturator in a desired position.

9. A spreader according to any preceding Claim and comprising a rectangular sheet steel float having one long notched edge and one short notched edge, said obturator comprising a sheet steel member on the reverse of said float.

10. A spreader according to Claim 9 wherein said obturator has a long and a short arm respectively for cooperation with said long notched edge and said short notched edge, said obturator being guided for movement at 450 to the longitudinal axis of said float.

11. A spreader substantially as described herein with reference to the accompanying drawings.