AU2004101034A4 - Adjustable level assembly - Google Patents

Description

09/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 05/18 ADJUSTABLE LEVEL ASSEMBLY 0 BACKGROUND The present invention relates to levelling devices in had tools and more particularly relates to an adjustable level assembly capable of attachment to a levelling tool such 00 0 5 as but not limited to a screeding tool. More particularly the invention relates to a bubble level which is capable of fine adjustment once in situ and which is detachably fixed to a work tool. More particularly the invention relates to a bubble level Sassembly which may be fine adjusted once it is fixed to a work tool.

PRIOR ART 0 O 10 Levels are extensively used in the building industry. Typically levels take the form of c<i a straight edge implement having a level element which includes a bubble capable of movement between marks which define a level position when the bubble is equidistant between the marks. The level element is normally fixed to the straight edge and is considered permanent. Also, such levels are considered permanent and are not detachable from the straight edge.

The prior at teaches a variety of levelling assemblies examples of which are described below.

United States Patent 4,691,445 discloses an instrument for establishing a horizontal plane for levelling ceilings, tables, floors and the like, consisting of a reference head having a translucent liquid reservoir, an adjustable field head, and a hose for interconnecting the two heads. With the level of liquid in the reservoir calibrated to correspond to the desired elevation, the liquid level at the field head at the other end of the hose will correspond to the selected reference level, thereby providing a means for defining a horizontal plane which is independent of a continuous line of sight A plurality of datum scales in visual juxtaposition with the reference head reservoir and correlated to the mounting channel or to the base of the retfrence head provide reference marks at known vertical distances from these mounting points.

United States Patent 4,773,161 discloses a portable liquid level comprising a bottle for holding levelling liquid and means in its lower end for connecting to a length of hose. The bottle has a filler opening in its upper end and integral means for

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COMS ID No: SBMI-01030127 Received by JP Australia: Time 12:54 Date 2004-12-08 09/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 06/18 o storing the hose around the bottle. The level may include a ventable bottle closure 0 over the filler opening and a ventable hose closure detachably mounted on the o extended end of the hose. The bottle may also include an integral dip on the outside surface of the bottle for receiving and holding an end portion of the hose. The bottle OO 5 may have an integral handle on one side thereof and a mounting plate attached to the other side thereof United States Patent 4,319,405 Levelling instrument A levelling instrument Cr) for use in the building and construction trades comprises a sighting telescope Sembraced by one or more support members for sighting along horizontal distances, a S 10 spirit level frame having at least one bubble level tube mounted therein for indicating the horizontal alignmaet of the sighting telescope, and a levelling platform having a o plurality of vertically adjustable legs for levelling the instrument on a support surface.

The aforementioned components are maintained in relative alignment by means of flat planar mating surfaces without rigid mechanical connection therebetween in order to facilitate rapid assembly and disassembly of the instrument and compact storage. The sighting telescope includes a pair of intersecting crosshairs which may be manually adjusted in elevation, making it possible to sight along non-horizontal lines without physically tilting the levellig instrument as a whole. The sighting telescope suppott members are charactedzed by a two-part constrction with fastener-recessing cavities in the base section thereof thereby providing a substantially unobstructed flat planar base surface portion for resting smoothly on the spirit level frame.

United States Patent 5,651,186 discloses a liquid level vial and method for making the vial for a builder's level which includes a body with an interior wall and a body cavity containing a bubble. A marker ring is exposed in the cavity. The ring is embedded in the body and the interior wall and the ring have surfaces machined and coextensive with one another, The bubble moves smoothly across the machined wall and ring surfaces. A new method for making a level vial includes providing an intermediate vial product with a body wall having at least one marker ring embedded in it and machining the wall and the ring to form a wall surface free of discontinuities.

The intermediate vial product is also disclosed.

2 COMS ID No: SBM1-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 08/12/2004 11:52 +61-2-95522894 WALSH AND ASSDCIATES PAGE 87/18 o United States Patent5,933,974 Combination square, level and plumbing tool A C carpeter's square having a first and second leg at right angles to each other, and a 0 third leg extending between the first and second legs. A magnetic strip on the first leg

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for attaching the tool to a metallic surface to be plumbed. A first notch in the third leg 00 5 a first distance from the first leg and a second notch in the third leg a second distance from the first leg so that a plumb string can be threaded through the first and second notches and thereby held in place to support a plumb bob to allow a plumb reading to C be taken without the need for manually supporting the plumb bob.

0 Levels are prone to damage on building sites and for this reason they are Susually of robust construction with the bubble level set in a protective recess.

C Traditional straight edge levels are suitable for jobs such a brickwork and carpentry but in the case of concrete screeding tradesmen have had to cope with inadequate solutions to ensur acceptable levelling of work.

One solution for ensuring level concrete is to place a conventional level on top of a screeder and hold both together while screeding. This is an unsatisfactory solution. Another option is to attach a detachable bubble assembly to a screed via an adjustable clamp. These clamp onto fixed or variable position, When fixing the clamp on screed level bubble assembly it is important to ensure that the bubble is parallel to the working face of the screed. This may be achieved by comparing the clamp on bubble to another level or by levelling the screed at two points at the screed ends and then reversing the screed to compare the reading. This is a time consuming and tedious process and often requires trial and error to eventually achieve accurate levelling.

There is a long felt want in the industry and art to provide a convenient means which allows accurate levelling of a screeding tool by providing a detachable level which allows fine adjustment for levelling purposes. There is also a need to provide a level having fine adjustment capability which is detachable so it can be protected from damage when not in use and may be selectively attached to a tool such as a screed for levelling a surface.

3 COMS ID No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 08/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 088/18

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c The present invention plovides an adjustable level for a screed tool which overcomes 0) the aforesaid defects in the prior art and provides a useful alternative to the known devices. The present invention also provide a substantial advantage over the known 00 0 5 devices by providing fine adjustments to a level assembly.

In one broad form the present invention comprises: Sa levelling assembly for attachment to a work tool; Sthe assembly comprising, a housing having a wall with an opening therein.

0 C- a liquid filled level including a bubble, a support frame, for receiving and retaining the level and including openings which align with holes in the housing and receive and retain therein fastmers wherein the fasteners allow adjustment of the attitude of the support frame relative to the housing to set the bubble to a level position.

Preferably, the levelling adjustment to the bubble level is effected by adjustment of the fasteners against rubberised O rings which are sandwiched between a screw head and a recess disposed in the support frame. According to a preferred embodiment, the support frame is adjustable about an axis normal to a longitudinal axis of the housing, wherein adjustment of the bubble in said level occurs with reference to surface markings on the level to indicate a level or out of level position ofthe bubble.

The levelling assembly is adaptable to a screeding tool but may be adapted to other tools which requires levelling. The screeding tool is for screeding a cemeutitous material such as wet cement or concrete and includes a region thereon which receives and retains the levelling assembly.

In another broad form the present invention comprises: a screeding tool oomprising; a levelling assembly bfr attachment to a work tool; 4 COMS ID No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 0812/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 09/18 0 the assembly comprising, a housing having a wall with an opening therein.

0 0 a liquid filled level including a bubble, Sa support frame for receiving and retaining the level and including openings which 00 o align with holes in the housing and receive and retain therein fasteners; wherein the fasteners allow adjustment of the attitude of the support flame relative to aC the housing to set the bubble to a level position; wherein the levelling adjustment to Sthe bubble level is effected by adjustment of the fasteners against rubberised O rings 0 which are sandwiched between a screw head and a recess disposed in the support Sframe.

Preferably the level housing is cylindrical and is formed from an aluminium extrusion. The fasteness are preferably self tapping screws and the support frame and bubble level are injection moulded.

Although the invention will be prima4ly described with referece to its application to a scmeeding tool it will be reognised by persons skilled in the art that the assembly desnribed herein may be applied in other applications.

BRIEF DESCRPTION OF THE DRAWIGS The present invention will be now described according to a preferted but non limiting embodiment and with reference to the accompanying illustrations wherein Figure 1 shows an exploded view of a level assembly according to a preferred embodiment with the bubble out of level; Figure 2 shows an exploded view of a level assembly according to a preferred embodiment with the bubble set at level; Figure 3a shows a perspective view of a housing according to a preferred embodiment.

COMS I0 No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 08/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 10/18 Figure 3 b shows an end view of the housing of figure 3a, Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 shows a side elevation perspective view of a housing according to a preferred embodiment.

shows a top view of a housing according to a preferred embodiment.

shows a side elevation of the level and support frame according to a preferred embodiment shows a. top plan view of the support frame according to a preferred embodiment.

shows a cross sectional view of the support frame according to a preferred embodiment.

shows a cross sectional view of the support frame inserted in a housing according to a preferred embodiment.

DETAILED DESCRIPTI The invention will be primarily described with reference to its application to a soreeding tool but it will be appreciated by persons skilled in the art that the invention may be attached to a variety of tools and devices used in or which must be level.

Referring to figure 1 there is shown an exploded view of a level assembly I according to a preferred embodiment. Levelling assembly 1 comprises a housing 2 having a wall 3 wilt an opening 4 therein. Opening 4 shown is ovoid but it will be appreciated that this may be any shape to accommodate a liquid filled level 5. Level 5 is liquid filled and capable of generating a bubble 6. Level 5 also includes markings 7 and 8 which define an area which is assumed by the bubble 6 when the assembly is level.

As shown in figure 1 bubble 6 is partially outside markings 7 and 8 so level 5 is out of level.

6 COMS ID No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 08/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 11/18 O Level 5 has associated therewith a support frame 9 which is a generally arcuate C element which includes holes 10 and 11. Arcuate support frame 9 includes a recess which conforms to the contour shape of wall 3 of housing 2. Holes 10 and 11 align with holes 12 and 13 ofwall 3 and receive fasteners 14 and 15. Holes 10 and 11 are 0 5 adjacent respective recesses 16 and 17 which receive and retain therein O rings 18 and 19. Fasteners 14 and 15 have respective heads 20 and 21 which sandwich 0 rings 18 and 19 0 rings 18 and 19 have inbuilt elastic memory which allows them to deflect Sunder load of the screw heads 20 and 21 when fasteners 14 and 15 are tightened.

SThe fasteners 14 and 15 allow adjustment of the attitude of the support frame 9 relative to the housing 2 to set the bubble to a level position. This is preferably 0achieved by compression by heads 20 and 21 ofO rings 18 and 19 whose deflection is C' sufficient to achieve adequate rotation of level 5 and consequential longitudinal movement of bubble 6. Bubble 6 is sensitive to rtational movement of level 5 about an axis normal to a longitudinal axis of housing 2 so that compression ofO rings 18 and 19 will provide enough rotation for fine adjustment of bubble 6 for levelling purposes. Assembly 1 is attachable to a screeding tool not shown.

The tool is level when the bubble on the assembly is set by the fasteners in between maldngs 7 and 8.

Prefeably the housing 2 is cylindrical and is formed from an aluminium extrusion.

The fasteners are preferably self tapping screws and the support frame and bubble level are injection moulded. Assembly I is attachable to a screeding tooL.

Figure 2 shows an exploded view of the level assembly of figure I with coresponding numbering and with the bubble set at level between markings 7 and 8.

Figure 3a shows a perspective view of housing 2 according to a preferred embodiment. Figure 3 b shows an end view of the housing of figure 3a.

Figure 4 shows aside elevation perspective viewof housing 2 and Figure shows a top view of housing 2. As may be seen from figures 4 and 5 housing 2 has a wall 3 with an opening 4 therein. Holes 12 and 13 of wall 3 and receive fasteners 14 and 7 COMS ID No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08 88/12/2004 11:52 +61-2-95522894 WALSH AND ASSOCIATES PAGE 12/18 O As shown in figure 5, opening 4 of wall 3 is ovoid but may be any shape to

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CN accommodate a liquid filled level 5 see figure Markings 7 and 8 define an area 0 which is assumed by the bubble 6 see figure 2) when the assembly is level. As shown in figure 1 bubble 6 is partially outside markings 7 and 8 so level 5 is out of 00 5 level.

Figure 6 shows a side elevation of the level and support frame 9. Figure 7 shows a top plan view of the support frame accoding to a preferred embodiment. Support Sframe 9 which is a generally arcuate element which includes holes 10 and 11. Holes and 11 include respective recesses 16 and 17 which receive and retain therein O rings 18 and 19 (see figures I and 2).

o As previously described Fasteners 14 and 15 have respective heads 20 and 21 which 0 sandwich O rings 18 and 19 which have inbuilt elastic memory which allows them to deflect under load of the screw heads 20 and 21 when fasteners 14 and 15 are tightened.

Figure 8 shows a cross sectional view of the support frame 9 and level 5. Figure 9 shows a cross sectional view of the support frame 9 inserted on wall 3 of housing 2 according to a prefened embodiment. Arcuate support frame 9 includes a generally concave recess 25 which conforms to the contour shape of wall 3 of housing 2.

Preferably the housing 2 is cylindrical and is formed from an aluminium extrusion.

The fasteners are preferably self tapping screws and the support frame and bubble level are injection moulded. Assembly 1 is attachable to a screeding tool.

It will be recognised by persons skilled in the art that numerous variations and modifications may be made to the invention broadly described herein without departing from the overall spirit and scope ofthe invention.

8 COMS ID No: SBMI-01030127 Received by IP Australia: Time 12:54 Date 2004-12-08