A - Technical field
[0001] The present invention finds its use in concrete and masonry construction practice:
it enables to obtain smooth and levelled reference screed points, indispensable to
achieve sand and/or cement floor screeds perfectly flat and at 90° angle with respect
to the reference height points, set upon the vertical surfaces such as walls and columns
and, at the same time, perpendicular to the entire sand and/or cement floor screed
being laid down before laying the floor covering or tiles.
[0002] The screed fixture consists of:
- n. 02 straight metal bars: a long vertical bar (1) and a short horizontal bar (7)
set at 90° to each other; these two metal bars are held in perfect alignment by n.
01 diagonal bracing metal bar (9);
- n. 01 handgrip (5) made of half-oval shaped metal rod placed on top of the long vertical
metal bar, which enables to apply "muscular" hand force in the top-to-bottom direction
of fixture and vice versa;
- n. 01 vertical rebate (6) machined at the heel of the long vertical metal bar
- n. 01 sliding metal plate (2) moving in vertical direction, equipped with n. 02 bolts:
a fixed bolt (3) - anchored to a threaded nut - and an adjustable threaded bolt (4)
fitted with a knob at one end - anchored to a threaded knob at the other end - the
sliding plate is necessary to obtain the desired height point setting, placed on the
upper part of the long vertical metal bar
- n. 01 horizontal rectangular metal plate (8) fitted beneath the short horizontal metal
bar (7)
B - Background art (current state-of-the-art)
[0003] In current building industry practice, in order to lay a cement and/or sand screed,
one has to start by first locating and setting height reference points on the surface
of the existing walls of a room; the location and setting of reference points, can
be done with the help of a common graduated rule, by taking the existing ceiling as
the starting reference point; then one would measure vertically down the existing
vertical wall until the desired height point is reached.
[0004] Once the desired reference height point has been obtained, the same value is set
and marked on all the vertical surfaces - existing walls or columns - by means of
suitable tools and instruments.
[0005] When all the reference height points have been set and marked off, one proceeds with
the formation of the concrete screed. At this point the concrete-layer pours the concrete
mix below each vertical height point previously marked and, with the help of a graduated
rule he determines the final height value of the screed; then by means of a spirit
level he obtains a plan or trace perpendicular and at 90° from the vertical height
point. By so doing one gets the final screed concrete thickness, to be laid flat,
necessary for accomplishing the successive guide pads or tracks, also made of concrete
mix. The aforesaid guide pads or tracks are made along the perimeter of the vertical
surfaces or walls and are indispensable to enable successive pouring and levelling
of the whole floor surface.
[0006] In fact, complete filling of the flat surface by concrete mix, is carried out by
hand with the aid of an aluminium straight edge, which is allowed to slide over the
perimeter guide pads or tracks previously obtained; and the concrete mix layer or
screed thickness thus obtained is perfectly flat and perpendicular to the vertical
height points, thus yielding a smooth and uniform surface.
[0007] The use of rule and spirit level to obtain the final height point value over the
concrete mix screed, from the vertical height point, is by no means functional and
effective, but the setbacks accruing from it are low speed, poor work performance
and precision.
C - Disclosure of invention
[0008] Having determined the reference vertical height point on the wall, by the method
illustrated previously; having then established the value of the height from the vertical
height point to the rough floor below; thus, after subtracting the thickness of the
concrete screed to be laid down and obtained the desired final height, the invention
fixture adjustment, in relation to the same final height as referred to above, is
carried out as follows: move upwards the steel sliding plate (2) till the desired
height measured by means of a graduated rule is reached, then lock it on this position;
at this stage the fixture is ready for use.
[0009] The next step consists in laying down the concrete by the operator under each and
every vertical height point just marked-off, by using the present fixture through
the handgrip (5) placed on the vertical alignment. This operation will be carried
out in the following way: the operator will have to grip and hold the fixture in front
of him, allowing it to slide along the vertical wall, by imparting it a manual alternating
up-and-down motion in direction top-to-bottom-to-top.
[0010] By this action, one will obtain flattening-out of the concrete mix by means of the
horizontal alignment and the horizontal rectangular steel plate (8) placed under the
aforesaid alignment. Such flattening will create a rectangular track perpendicular
and perfectly at 90° angle from the vertical height point.
[0011] In the very instant the rectangular sliding steel plate (2) anchored onto the upper
end of the long vertical bar (1), will match perfectly with the height point vertically
above it, the desired final height will be achieved, thus obtaining on the floor rectangular
height points of concrete mix screed perfectly horizontal and at 90° perpendicular
to the height points placed on vertical wall or column; each of these operations are
performed in keenly advantageous times and with an exceptional degree of precision,
equal for all the height points of screeds obtained.
[0012] It must be pointed out that the bottom face of the horizontal rectangular steel plate
(8) will leave a trace on the concrete screed, which will determine the width of the
guide pads or rails to be laid down. Therefore, the completion of guide pads or rails
made of concrete mix, will have to be "levelled" or "smoothed down" by means of aluminium
straight edge, in order to obtain a plan perfectly horizontal and perpendicular to
the vertical height points.
[0013] At this stage, the operation of filling with concrete mix the empty floor spaces,
between one rail and another, will take place; the concrete mix screed will be levelled
and smoothed down by means of aluminium straight edge, which will be made to slide
on the guide pads or rails previously obtained, thus forming a plan uniform and perpendicular
to all vertical height points.
[0014] Hence, the main goal of the present invention is that of getting level rectangular
reference floor screed of concrete mix, perfectly perpendicular at 90° to the height
points placed on vertical walls or columns.
[0015] Another goal of the present invention, is that of performing two operations simultaneously
in one step, that is: obtaining the final floor screed thickness perpendicular at
90° angle to the walls or columns. Yet another goal of the present invention is that
of performing above illustrated operations employing a fast, simple and economical
fixture, at a contained cost in proportion to the advantages that can be attained.
[0016] Further scopes and features of the present invention will appear more obvious, from
the following detailed description of one typical construction of fixture, preferred
but not exclusive, taken as an example but not as a limitation, expressly referred
to the attached drawings.
D - Brief description of drawings
[0017] Reference is made to enclosed drawings Fig. 1/2 and Fig. 2/2 showing the main parts
of the invention.
[0018] Fig. 1/2 shows a side view of the fixture, featuring:
- Item N.1: a long vertical metal bar equipped with a rectangular sliding metal plate
- Item N.2 - clamped on its upper end, guided by a slot machined on it, to enable
it to be shifted along its axis in a top-to-bottom direction and vice versa, constrained
by a bolt - Item N.3 - anchored with a nut to Item N. 1 to ensure perfect alignment
and easy sliding over Item N. 1.
[0019] Further, the rectangular sliding metal plate Item N.2, in turn, is equipped with
a second threaded bolt - Item N.4 - with knob shaped head on one end and a threaded
knob-shaped anchor nut on the other, to set and lock the rectangular sliding metal
plate Item N.2 to the desired height point.
[0020] Further, the upper part of the fixture long vertical metal bar is provided with a
half-oval shaped metal rod handgrip - Item N.5 welded to the long vertical metal bar
N.1, which enables to operate the present invention by applying muscular force in
vertical top-to-bottom direction.
[0021] The long vertical metal bar N.1 has a rebate - Item N.6 - milled on its heel: the
reason for rebating the heel of Item N.1, is to prevent the fixture from hitting the
strip filled perimeter expansion joints - employed to ease the expansion of the concrete
screed - during the use of this invention. Item N.7 shows the shorter horizontal metal
bar: this is perpendicular to, and perfectly set at an angle of 90° with respect to
the long vertical metal bar Item N.1. Moreover, the shorter horizontal metal bar Item
N.7, is connected at 90° angle to the long vertical metal bar Item N.1, by electric
welding.
[0022] Further, Items N.1 and N.7 are connected to each other by a diagonal metal bracing
bar - Item N.9 - set at 45° angle by means of controlled electric welding, to prevent
any deviations from the 90° angle alignment between Items N.1 and N.7, due to induced
heat stresses and strains.
[0023] Fig. 2/2 shows a perspective front view of the fixture, featuring: The horizontal
metal bar - Item N.7 - has a rectangular metal plate - Item N.8 - welded horizontally
beneath the whole base length, with the purpose of marking a rectangular trace upon
the concrete mix screed.
[0024] The horizontal metal plate - Item N.8 - also, in turn, is perpendicular to and perfectly
at 90° angle to the long vertical metal bar Item N.1.
[0025] The rectangular metal plate - Item N.8 - has the same length dimension as the horizontal
metal bar - Item N.7 - but it is wider (being rectangular) than Item N.7 and, therefore,
it becomes perpendicular to horizontal metal bar, Item N.7, and perfectly at 90° from
it, forming a perfectly horizontal rectangular surface under the two Items N.1 and
N.7, also perfectly perpendicular at 90° to the long vertical metal bar Item N.1.
[0026] The thickness of the horizontal metal plate - Item N.8 - is greater than that of
Items N.1 and N.7.
[0027] The purpose of making this thickness greater is that one of obtaining a more precise
and defined trace.
[0028] With reference to the side view of figure 1/2 the long vertical metal bar, Item N.1,
and the horizontal metal bar, Item N.7, not only are these elements connected to each
other at a perfect 90°angle, by means of electric welding; but the diagonal metal
bracing bar - Item N.9 - also is connected to Items N.1 and N.7 by electric welding.
[0029] The function of a diagonal metal bracing bar, Item N.9, called also "bend-preventive",
is that of performing a perfect operation of the present invention, with the view
of preventing that, during its operation by the application of a muscular vertical
force in a top-to-bottom direction, and vice versa, the fixture might be subjected
to such values of bending which might compromise the alignments of Items N. 1 and
N.7; thus enabling the correct use of the present invention, that is the bend-preventive
bar - Item N. 9 - placed diagonally between the horizontal and the vertical Items
N.1 and N.7, ensures that the alignments of the two Items N.1 and N.7 do not go out
of their perfect 90° angle alignment, in such way that also the horizontal metal plate
- Item N.8 - welded beneath the horizontal metal bar, Item N.7, does not undergo alterations
that might compromise its perfect perpendicular equilibrium at 90° angle with the
long vertical metal bar Item N.1.
[0030] As above illustrated, the present invention is made up of Items N. 1/ N. 2/ N. 3/N.
4/N.5 N. 7/N.8 and N. 9.
E - Best mode for carrying out the invention
[0031] All the parts of the present invention are totally made of steel, connected between
them by electric welding and bolts; the only exceptions being a bolt and a nut made
of metallic material with a plastic knob.
[0032] Particular mention must be made about the extremely constructive simplicity of the
present invention, which enables its manufacture at extremely reasonable costs.
[0033] Further, the present invention is susceptible of numerous variants and modifications,
all included within the domain of the invention concept.
[0034] The present invention, apart from being operated by muscular force, can be modified
to be operated by means of an electric motor, a hydraulic motor, or a pneumatic motor.
[0035] All the materials can be replaced with other elements technically equivalent.
[0036] The materials, the shape and the dimensions can be of any kind depending upon the
requirements, provided that they are included in the concept of solution illustrated
above and claimed further on.
F - Industrial applicability
[0037] As previously described, despite the manufacturing alternatives the present invention
cannot have extensions of application outside the building field.
G - Extent of the required protection
[0038] Having fully described the present invention, with reference to a preferred typical
example of construction and to some alternatives for its implementation, which fall
into the domain of the invention concept; it is obvious the inventor's intention of
protecting its invention from any and all forms of construction which do fall within
same concept of invention which do achieve equal usefulness of results, with regards
to both the description that precedes, and the claims which follow; protection of
the invention from all kinds of implementation and variations which are reflecting
the spirit and the scopes of the invention itself, is also required.
1. The floor screed laying fixture, basically consists of n. 2 metal assemblies of different
lengths, joined perpendicular to each other. It is suitable for determining horizontal
level points on a floor in relation to vertical points marked on vertical surfaces:
walls and/or columns,
The longer assembly, located vertically over the shorter one, is characterized by the fact that, it features a half-oval shaped metal handgrip, welded on the front
edge of its upper end, which enables the application of muscular force on the fixture.
The shorter assembly, located horizontally underneath the bottom of the longer vertical
assembly, is characterized by the fact that a horizontal rectangular metal bar is fitted beneath it and perpendicular
to the vertical assembly itself.
2. The fixture, as per claim n. 1, is characterized by the fact that, the two assemblies are connected and strengthened by a diagonal metal
bracing bar.
3. The fixture, as per claims n. 1 and n. 2, is characterized by the fact that, the longer vertical assembly features a vertical rebate machined on
its heel.
4. The fixture, as per previous claims n. 1-2-3 is characterized by the fact that, the longer vertical assembly has, fitted on its upper end face, a
sliding metal plate that can be adjusted vertically up-or-down: this plate has a slot
machined through its thickness and it is anchored to the fixture by means of threaded
bolt and nut which enable, at the same time, the sliding and setting of the plate;
a second threaded bolt with knob-shaped head and knob-shaped nut, is present and it
has the scope of locking the sliding plate on the desired height point.
5. The fixture, operated by the application of muscular force, as per claims n. 1-2-3-4,
has the characteristics described and illustrated in the attached drawings as well
as in the above specified scopes.