Note: Descriptions are shown in the official language in which they were submitted.
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Brick Laying Device
The invention relates to a brick-laying device; in particular such a device
for
assisting in the brick-laying process.
Various problems are known with conventional brick-laying processes. In such
processes a course of bricks is laid together with mortar and further courses
laid on top until a wall, pillar or other brick-work is completed. The
standard
of the brick-work achieved is normally down to the skills of the individual
brick layer, in particular in ensuring an even and consistent gap between each
successive course of building bricks or blocks. The main problem in inexpertly
laid brick-work is the inconsistency of the finished product. For example the
mortar beds vary in thickness giving way to different heights of the brick-
work
from corner to corner as a result of which the wall may not be level. Bricks
can
be laid in different planes to one another as a result of the inherent
softness of
the mortar bed. In particular, any pressure that is applied to the brick
forces it
further into the mortar bed either directly when the brick is being laid or
indirectly when pressure is being applied from an additional course above.
Because all bricks cannot be laid with the same pressure these inconsistencies
come to light over the finished wall. As a result, even for skilled
bricklayers,
achieving high quality brick-work is a time consuming task. There is currently
a decline in the number of skilled bricklayers who can achieve a good standard
of work which in turn gives rise to a problem with the future supply of brick
layers as training facilities may not be available.
One known proposed solution to the problem is described in French patent
application no. 2600359. According to the arrangements disclosed in this
document, a brick laying aid includes a latticed structure having marginal
elongate beads. The structure is laid atop a course of bricks with the beads
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lying along the edges and mortar is added. Once the mortar has dried the bead
can be removed or left in place. In either case various problems arise with
this
arrangement. Because of the external beading the device needs to be
positioned precisely onto the brickwork. Mortar is effectively placed within
the device, between the beads, such that when the next course of bricks is
laid
there will be no excess mortar squeezed from between the bricks such that a
satisfactory bond may not be obtained. The recess formed by removing the
bead may be too deep and the beads may also prevent the effective shedding of
water which can be essential for longterm performance. Furthermore the
device requires significant amounts of material and, because of the elongated
cylindrical beads, can give rise to production and storage problems.
Another proposed solution is described in International patent application
number WO 02/090688 commonly assigned herewith and incorporated herein
by reference. This document describes a spacer that is laid along a course of
brick-work and of smaller width than the brick-work such that it is fully
enveloped in mortar during the brick-laying process. The spacer comprises a
lattice or mat on which a plurality of spacer elements are joined together by
a
support structure comprising elongate ribs. The spacer elements are provided
at intervals in the elongate direction and the arrangement provides an
improved
bond because the entire spacer in enveloped in mortar. However, the bond
between the bonding material and the building block is not ideal as the
bonding
material can 'bottom out' when the next course of building blocks is placed on
top of the spacer and bonding material, the bonding material being squeezed
out where the lattice meets the building block. This results in an incomplete
bond between building blocks and bonding material at the location of the
spacer elements. The ribs joining the spacer elements can also prevent a
complete bond between bonding material and lattice mat. Furthermore,
although the spacer is designed to be completely enveloped in bonding
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material, it may protrude from the bonding material if not correctly located
on
the building block.
Various areas are available for further improvement of the known
arrangements. It is desirable to increase yet further the structural stability
of
known spacer mats and also to reduce the mass of material, such as plastic, at
the end of each course of brick-work. It is also desirable to reduce the
amount
of material in the spacers. It is yet further desirable to provide a spacer
capable
of compact storage. Although the systems described above provide significant
improved bonding between the spacer and the mortar, it is desirable to improve
the bonding yet further. Furthermore it is desirable to improve the stability
of
building elements attached to the end of a course of bricks and to reduce the
mass of spacer material at the end of courses whilst retaining the possibility
of
attaching building elements.
The invention is out set out in the claims.
Various advantages are attached to the aspects of the invention set out in the
claims. For example because spacer elements are provided in a non-parallel
configuration, the structural strength of the spacer mat is enhanced. In
particular "parallelogram" collapse of the spacer mat is avoided. Furthermore,
this configuration reduces the amount of spacer mat material at the end of a
course of bricks. Because of the provision of cut-out portions in the spacer
elements the amount of material is reduced and spacer mats can be stacked
more compactly. Because the support elements are significantly inset relative
to the edges of the spacer mat yet further improved bonding of mortar or other
bonding material around the support elements is achieved. The provision of
first and second parallel end spacer elements once again reduces the amount of
spacer mat material at the end of the course of bricks.
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In other embodiments, the spacer elements of the present invention are
enveloped in bonding material in both dimensions and tapered top and bottom
to allow maximum contact between the bonding material, such as mortar, and
the brick. This allows an improved bond to be obtained.
Because a continuous spacer element is located at the end of the spacer this
enables the fixing of door and window jambs by means of screws without the
need for rawl plugs or fixing anchors. Because the end spacer element is
thickened with respect to the other spacer elements this improves strength and
support for screw fixings.
The provision of retaining clips assist in the correct location of the spacer
in
relation to the brick on which it is placed. This ensures that the spacer will
not
protrude from the mortar, or bonding material.
The provision of the support strips in the middle of the spacer elements
enabling the supports to be encased in the bonding material, to improve the
strength of the bond between brick and mortar, top and bottom.
Embodiments of the invention will now be described, by way of example, with
reference to the drawings of which:
Figure la is a perspective view of the spacer mat according to a first
embodiment of the present invention;
Figure lb is a perspective view of a length of spacer mat;
Figure 2 is a perspective view showing two spacer mats stacked for storage;
Figure 3 shows a detail of an end portion of a spacer mat to be laid at the
end of
a course of brick-work;
Figure 4 shows an alternative form of spacer mat;
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Fig. 5 is a perspective view of the first embodiment of the invention;
Fig. 6 is a plan view of the first embodiment;
Fig. 7 is a side view of the first embodiment;
Fig. 8 is a side view of a wall constructed according to the present
invention;
5 Fig. 9 is a perspective view of the spacer mat located with a retaining clip
according to a further embodiment of the invention;
Fig 10 is a side view of a door frame attached to a wall according to a
further
embodiment of the invention.
Referring to Fig. 1 a the arrangement is designated generally 10 and includes
a
course of bricks or blocks 12 with a spacer mat 14 laid thereon. The spacer
mat 14 comprises a pair of parallel ribs or support strips 16 along which are
spaced a plurality of vertical spacer elements 18 extending upwardly and
downwardly therefrom. The spacer mat 14 is elongate and of width slightly
smaller than that of the course of bricks 12 and the spacer elements 18 are
arranged at intervals in the elongate direction along each support strip 16.
The support strips 16 and spacer elements 18 are preferably formed integrally
of plastic material such as a polymer material, polypropylene, PVC, HDPE or
nylon. The support strips 16 are preferably circular in cross-section with 3mm
diameter and the spacer mat can be formed in any appropriate manner as will
be apparent to the skilled person for example injection moulding, extrusion or
a
spinning dye, preferably by pressure injection method. The spacer mat can be
cut to an appropriate length or shape to deal with corners and angles and the
spacer elements 18 preferably extend upwardly and downwardly slightly less
than the desired spacing between courses of bricks to take into the account
the
mortar film that tends to form on the top of the spacer elements 18.
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It will be appreciated that the invention can be utilised other than in
straight
courses of brick-work. For example a pillar arrangement comprises effectively
a hollow square formed of bricks in a one and a half brick arrangement. In
this
case the spacer is cut into lengths and laid atop the course of bricks after
which
the next course is laid in the manner described above. Generally the spacer
mat
can fit any angle or curve.
The spacer mat 14 can be provided in lengths or rolls dependent on the
material
or can be provided as individual elements for example spacers to fit single
brick as shown in Fig. 1 a.
In the embodiment shown in Fig. 1 a the width dimension of the spacer is
preferably 80mm, less than that of a standard brick, to enable the spacer to
be
wholly embedded within bonding material (with approximately lOmm
clearance at either side). The spacer mat 14 is placed on top of the brick
course.
Once the spacer mat is in place mortar is applied and the bricklayer can then
position the next layer of bricks by applying downward pressure to compress
the mortar until the underside of the brick rests on the spacers. During the
process the mortar will pass between the support strips ensuring that the
necessary bonding in successive layers has occurred and that the integrity of
the structure is assured. Because the spacers are arranged at intervals and
are
inwardly positioned relative to the course of bricks, when downward pressure
is applied excess mortar can be removed ensuring a firm bed.
Significantly it will be seen that the support strips 16 extending in the
elongate
direction are joined by support strips 22 perpendicular to them in the form of
cross-bars, providing a generally rectangular grid. The spacer element 18 are
located at each vertex of the support elements 16 and 22. The spacer elements
18 extend generally at 45° to the support elements and adjacent spacer
elements
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are orientated: perpendicular to one another such that the orientation of the
spacer elements alternates in the elongate direction (i.e. in the direction of
the
course of bricks) as well as the width direction (i.e. transverse to the
elongate
direction in the plane of the course of bricks). The support elements 16, 22
S pass generally through the centre of the spacer elements 18 such that the
spacer
elements project symmetrically upwardly and downwardly as well as inwardly
to and outwardly of the spacer mat. The spacer elements are generally H-
shaped, elongate in the plane of the course of bricks and the direction of
orientation and with central cut-outs 24 top and bottom. The spacer elements
18 taper from their vertical centres top and bottom.
As a result of the configuration various advantages are realised. By disposing
the spacer elements non-parallel to the lateral support elements the amount of
material at the end of the course of bricks is reduced. By disposing the
spacer
elements non-parallel to each other the risk of collapse is reduced in
particular
in relation to the possibility of a shear deformation of the spacer mat.
Tapering
of the spacer elements reduces the possibility of "bottoming out" i.e. mortar
being pressed out between a top and bottom of the spacer element and the
adj acent brick. Provision of the cut-outs reduces the amount of material
without affecting the structural strength. In practice as much as 25% less
material can be used because of the cut-outs.
The spacer elements are. located at regular intervals in both dimensions,
providing a number of spacers, in this embodiment eight, underneath each
brick ensuring that the brick is level and plumb. The spacer elements
intermediate the ends are non-continuous across the width or lateral dimension
of the space mat and 20mm in length with approximately 52mm separation
between inner tips, being joined in the lateral direction by the further
support
strips 22 defining a centre to centre spacing of the spacer element of 66mm.
In
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cross section the spacer elements comprise a thickened centre portion of
approximately 4mm width tapering to a point top and bottom. The spacer
elements have a height of 9mm leaving lmm mortar top and bottom when
embedded.
Because the support strips 16 and 22 are provided intermediate the top and
bottom of each spacer element 18 this allows the support strips to be encased
more effectively in bonding material. Furthermore because the spacer elements
18 are provided laterally symmetrically about the support elements 16, the
support elements 16 are inset significantly from the edge of the spacer mat
and
from the course of bricks providing improved bonding with and enveloping in
moi tar.
Referring to Fig. lb a length of spacer mat is shown having length
approximately 870mm. It will be seen that the spacing between successive
adjacent lateral support elements 22 alternates between a wider and a narrower
spacing of 68mm and 45mm respectively. Two wider-spaced zones and one
central narrower-spaced zone define a region of the spacer mat arranged to be
aligned with a brick, the region having a total length of 181mm.
Referring now to Fig. 2 a further advantage of the cut-outs 24 and the spacer
elements 18 can be seen. Respective spacer elements 14 and 18 can be stored
by overlaying, one on the other, the support elements 16 of one spacer mat 14
laying in the recesses 24 of the adjacent spacer mat 14. As a result the
storage
volume is reduced, reducing the storage and transportation costs accordingly.
This is enhanced by providing the support elements centrally to the spacer
elements.
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In a further embodiment of the invention 1 as shown in Fig. la, retaining
clips
17 can be attached to ensure the correct location of the spacer not relative
to the
brick. The retaining clip 17 comprises a right angle, both arms being
preferably
approximately l Omm in length. One arm of the clip is positioned parallel to
the
top edge of the brick and clips onto the support strip 16. The other arm is
perpendicular to the first a1-m, and engages on the external edge of the brick
and prevents the spacer from moving from its proper location. The retaining
clip 17 is preferably formed of plastic material of similar or the same type
to
the spacer mat. Retaining clips 17 can be used in conjunction with the spacer
mat to ensure that the mat is correctly positioned on the bricks, to remove
the
risk of the mat protruding from the bonding material during brick-laying.
In an alternative embodiment the support strip or element 16 can be provided
close to the edge of the course of brick-work by appropriate dimensioning of
the spacer mat 14 and by reducing the inset of the support element 18 relative
to the spacer element 18.
Referring to Fig. 3 an end portion of a spacer mat 14 to be provided at the
end
of a course of brick-work is shown in more detail. It will be seen that first
and
second end pieces 26 extend between the spacer elements 18 at the end of the
spacer mat 14. A first end piece 26 extends between the centres of the spacer
elements 18 and can, for example, replace the lateral support element 22, or
the
lateral support element 22 can be increased in height and thickened as
appropriate. A second end piece 26 is shown spaced from and parallel to the
first end piece 26 and extending between the inner end of the respective
spacer
elements 18. The end pieces 26 are generally of a similar height to the spacer
elements 18 and of increased thickness in relation to the spacer elements for
example between 4 and 8 millimetres preferably 6 millimetres. As a result
when building elements such as a window or door jamb (not shown) are
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attached to the end of the course work the end pieces 26 can act as fixing
anchors for screws or other fixings such that rawl plugs and the like are not
required. The provision of two spaced and parallel end pieces 26 provide
additional stability of fixings passed through both end pieces.
It will be appreciated that the spacer element can be placed at any
appropriate
orientation, for example in the range of 10° to 80° more
preferably 30° to 60°
unless preferably 45°. Of course this range also includes mirror
inversions of
the angles. In addition although the spacer elements are shown as having
alternating orientations, any orientation pattern can be adopted for example
two
adjacent spacer elements orientated in the first direction, next to in non-
parallel
direction as so forth or any other appropriate pattern. Furthermore, curved
spacer elements can be provided.
In a further embodiment shown in Figure 4 the spacer elements 18 are shown
oriented parallel to the width direction of the spacer mat 14 and with cut-out
portions 24 arranged to receive, and aligned with the support elements 16 to
provide improved stacking. The spacer elements are approximately 20mm in
length and the overall width of the spacer mat from spacer tip to spacer tip
is
80mm, the spacing between the support strips 16 being 60mm. Once again the
transverse spacer elements define alternating narrower and wider regions of
respective dimensions 33mm and 80mm defining a zone of length 193mm
corresponding to a brick on which the spacer mat is laid. As with the
embodiment described with reference to Figs. 1 to 3, the mat spacing coincides
with the brickwork bonding providing an improved bond in this way.
Referring to Fig. 5 the arrangement is similar in general configuration and
construction to that of Fig. 1 and share similar reference numerals where
appropriate.
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However it will be seen that an end spacer element 15 in the length dimension
of each spacer mat is provided which is continuous and preferably thickened in
relation to the other spacer elements. The support strips 16 form the elongate
edges of the spacer, and the continuous end spacer elements 15 form the
shorter
edge of the spacer, perpendicular to the support strips. In cross section the
spacer elements 51 ~ have a height of 9mm and comprise a thickened centre
portion of approximately 4mm width tapering to a point top and bottom.
Because the spacer elements are tapered in the vertical direction when
downward pressure is applied maximum contact is allowed between the mortar
and the brick, providing an improved bond.
Refernng to Fig. 10, window/door jamb 20 is shown attached to the end spacer
element 15 with screws 19 removing the need for rawl plugs or fixing anchors.
In a further embodiment of the invention as shown in Fig 9, retaining clips 17
can be attached to ensure the correct location of the spacer, relative to the
brick.
The retaining clip 17 comprises a right angle, both arms being preferably
approximately l Omm in length. One arm of the clip is positioned parallel to
the
top edge of the brick and clips onto the support strip 16. The other arm is
perpendicular to the first arm, and engages on the external edge of the brick
and prevents the spacer from moving from its proper location. The retaining
clip 17 is preferably formed of plastic material of similar or the same type
to
the spacer mat. The retaining clips 17 can be used in conjunction with the
spacer mat to ensure that the mat is correctly positioned on the bricks, to
remove the risk of the mat protruding from the bonding material during
bricklaying as shown in figure 9.
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It will be appreciated that the invention can be utilised other than in
straight
courses of brickwork. For example a pillar arrangement comprises effectively
a hollow square formed of bricks in a one and a half brick arrangement. In
this
case the spacer is cut into lengths and laid atop the course of bricks after
which
the next course is laid in the manner described above.
As a result an improved building structure is provided. The spacers are
provided internally of the brickwork course allowing a firm bedding to be
obtained without blocking excess mortar from escaping. The spacer elements
are tapered to increase the amount of mortar in contact with the bricks to
either
side of the spacer mat, and to prevent tthe risk of 'bottoming out'. The end
spacer element is continuous and thickened to allow attachment of
window/door jambs. The support strips are located in the middle of the spacer
elements, to ensure that they are encased in bonding material, to increase the
bond between brick and mortar and provide a more stable structure.
It will be perceived that the invention gives numerous advantages in addition
to
those specified above. This spacer is robust, chemically and temperature
inert,
stable and long-lived and chemically strong. It is simply and intuitively used
and gives rise to a stable strong structure without effecting the appearance
of
the structure.
The spacer elements themselves can be of any appropriate form and dimension
and can be formed integrally with the support structures or bonded or adhered
to them. The distribution of spacer elements can be varied as required to take
into account building block dimensions, right angles or angled joints. The
support strips themselves can also be formed of any appropriate material not
limited to plastic material and including, for example, ceramics, cement or
metal materials. The spacer elements can be formed in lengths or in other
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shapes and/or of other materials to meet specific brick-work requirements or
for use with other types ~of building blocks such as breeze-blocks as
appropriate.
