Note: Descriptions are shown in the official language in which they were submitted.
CA 02887533 2015-04-13
METHODS AND APPARATUSES FOR ALIGNING TILES
TECHNICAL FIELD
[0001] This document describes methods and apparatuses for aligning tiles
with one
another.
BACKGROUND
[0002] Tile levelling devices exist for aligning the external faces of
adjacent tiles
flush with one another during installation. One type of device uses a clip
that is embedded in
unset mortar below the adjacent tiles, with a frangible stem extending through
the tile gap. A
ratchet wedge is inserted into an aperture in the stem and positioned across
the adjacent tiles
until the tiles are gripped between the base and wedge. Another device uses a
base that is
embedded in unset mortar, and into which a stem is threaded until a disc
connected to the
steam clamps the tiles between the base and disc. In both cases after the
mortar sets the stem
is removed or severed from the base, leaving the base permanently embedded
within the
mortar.
SUMMARY
[0003] A tile alignment device is disclosed comprising: a shaft having a
handle end
and a blade end; opposed blades extended laterally from the shaft at the blade
end; and a
pressure plate mounted on the shaft to define respective tile receiving
recesses between the
pressure plate and the respective opposed blades.
[0004] A combination is disclosed comprising: a tile alignment device;
adjacent tiles
each clamped within a respective one of the tile receiving recesses, in which
external faces,
of the adjacent tiles, contact the pressure plate and are flush relative to
one another.
[0005] A method is disclosed comprising: inserting a blade end of a shaft
into a gap
between side walls of adjacent tiles, the blade end having opposed blades
extended laterally
from the shaft; hooking the opposed blades underneath the adjacent tiles; and
clamping the
adjacent tiles between the opposed blades and a pressure plate mounted on the
shaft.
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[0006] A tile levelling device is disclosed comprising a shaft having a
handle end and
a blade end, opposed blades extending laterally from the shaft at the blade
end, and a
pressure plate spring mounted on the shaft to define respective bights between
the pressure
plate and the respective blades for receiving adjacent respective tiles. A
tile face alignment
device is disclosed comprising: a shaft; first and second prongs laterally
extended from
opposite sides of a base of the shaft; a pad mounting a portion of the shaft
for relative axial
movement within a passage through the pad, in which in use first and second
tile receiving
channels are defined between the pad and the first prong, and the pad and the
second prong,
respectively; and a shaft tensioner between the pad and the shaft.
[0007] A combination is disclosed comprising: a tile face alignment device;
a first
tile positioned within the first tile receiving channel; a second tile
positioned within the
second tile receiving channel; and in which tension is applied to the shaft
via the shaft
tensioner to pull the first and second -prongs toward the pad to grip the
first and second tiles
such that first and second external faces, of the first and second tiles,
respectively, contact
the pad and are flush relative to one another.
[0008] A method is disclosed comprising: inserting a base of a shaft into a
gap
between side walls of adjacent tiles, the base having prongs laterally
extended from opposite
sides of the base; positioning the prongs underlie the adjacent tiles, with a
pad overlying the
adjacent tiles and mounting the shaft within a passage through the pad; and
applying tension
to the shaft relative to the pad to draw the prongs toward the pad to grip the
tiles and align
external faces of the tiles flush with one another.
[0009] In various embodiments, there may be included any one or more of the
following features: The pressure plate is spring mounted on the sh'aft. A coil
spring mounted
concentrically around the shaft. A handle mounted to incrementally translate
along the shaft
to adjust pressure on the pressure plate. The handle is threaded to the shaft.
The pressure
plate forms part of a spool. The spool has flanged ends spaced by a sleeve to
define a finger
receiving recess between the flanged ends, in which the pressure plate forms
one of the
flanged ends. A torque transfer connection between the pressure plate and the
shaft. The
torque transfer connection comprises one or more of a spline to spline
connection, a keyway
and key connection, and a lateral pin and axial slot connection. Each of the
opposed blades
2
has a knife edge facing one of a counter-clockwise or clockwise direction of
rotation. Each
of the opposed blades has a side wall facing the other of a counter-clockwise
or clockwise
direction of rotation. The shaft comprises first and second shafts, with one
of the opposed
blades extended from the first shaft and the other of the opposed blades
extended from the
second shaft. Side walls of the adjacent tiles contact the shaft. Before
inserting, positioning
the adjacent tiles on an unset mortar bed; after the adjacent tiles are
clamped, withdrawing
the shaft and opposed blades through the gap. Withdrawing is done after the
mortar has
partially set. Hooking further comprises rotating the shaft.
[0010] This paragraph is intentionally left empty.
BRIEF DESCRIPTION OF THE FIGURES
[0011] Embodiments will now be described with reference to the figures,
in which
like reference characters denote like elements, by way of example, and in
which:
[0012] Figs. 1-3 are a sequence of side elevation section views of a
tile alignment
device being positioned between adjacent tiles (Fig. 1), used to clamp the
adjacent tiles (Fig.
2), and withdrawn from the tiles (Fig. 3). Dashed lines are used to show the
blades (Fig. 1)
and handle (Fig. 2) in different positions.
[0013] Fig. 4 is a section view taken along the 4-4 section lines in
Fig. 1.
[0014] Figs. 4B-C are section views of alternative torque transfer
connections
between the shaft and pressure plate. Dashed lines are used in Fig. 4B to show
two different
connections.
[0015] Fig. 5 is a perspective view of a blade end and blades of the
shaft of the
device of Fig. 1. Dashed lines are used to show the dimensions of the back of
one of the
blades not otherwise visible in the view.
[0016] Fig. 6 is a further embodiment of a tile alignment device.
[0017] Fig. 7 is a further embodiment of a tile alignment device with
dual shafts.
[0018] Fig. 8 is a further embodiment of a tile alignment device with
dual shafts, and
respective springs for each shaft.
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Date Recue/Date Received 2021-10-12
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[0019] Fig. 9 is a further embodiment of a tile alignment device with dual
shafts
formed of a single bent wire.
DETAILED DESCRIPTION
[0020] Immaterial modifications may be made to the embodiments described
here
without departing from what is covered by the claims.
[0021] There are numerous functional and aesthetic benefits to installing
tiles on a
wall or floor surface with consistent spacing and top faces flush between
adjoining tiles.
When laying tiles, or other surface cladding panels, it may be important that
the tiles are laid
evenly relative to the adjacent tiles. If the tiles are laid inconsistently,
the finished job may
be visually unsightly and may create safety concerns from tile edges and
corners projecting
beyond the plane of the greater surface. In addition, if sufficient spacing is
not provided
between adjacent tiles, the tiles may not be able to expand or contract on
account of thermal
or moisture changes, leading to cracking.
[0022] In order to lay tiles evenly, a tiler takes into account the space
between
adjacent tiles, making sure that the spaces are consistent and of uniform
thickness. A
common goal is to lay the external surfaces of the tiles on the same plane as
far as possible,
so that the matrix of tiles has the appearance of being flat and consistent.
Alternatively, in
the scenario where this is not possible, for example where there is fall in
the floor to
accommodate drainage, then the adjacent edges should as far as possible be set
to the same
height to avoid a "step" occurring between adjacent tiles edges. Such steps
may reduce the
overall visual quality of the finished job, and may possibly create a trip
hazard or restrict
water flow.
[0023] Tiles are typically laid manually and spaced using small disposable
plastic
crosses or other such spacers. While this is suitable for spacing the tiles,
the issues of flatness
is not addressed by such spacers. Flatness may be obtained by experience and
skill, but even
an experienced tiler can produce stepped tiles due to tile settling after
proper positioning.
[0024] Referring to Figs. 1 and 2, a tile alignment device 10 is
illustrated, comprising
a shaft 12, opposed blades 14, and a pressure plate 16. Referring to Fig. 2,
shaft 12 may have
a handle end 18 and a blade end 20. Shaft 12 may comprise a bolt shaft as
shown. Opposed
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blades 14 may be extended laterally from the shaft 12 at the blade end 20.
Pressure plate 16
may be mounted on the shaft 12 to define respective tile receiving recesses 22
between the
pressure plate 16 and the respective opposed blades 14.
[0025] The compression plate 16 may form part of a spool 30. The spool 30
may
have flanged ends 32 spaced by a sleeve 34 to define a finger receiving recess
36 between
the flanged ends 32. The pressure plate 16 may form one of the flanged ends
32A as shown.
A spool 30 permits finger receiving recess 36 to have an annular shape, which
allows a user
to insert fingers (not shown) within the recess 36 from any angle. An
underside surface 40 of
the upper flanged end 32B, or a transition wall 38 between the sleeve 34 and
flanged end
32B, or both, may be sloped or curved to fit the naturally round sides of a
user's finger (not
shown).
[0026] The pressure plate 16 may be spring mounted on the shaft 12, for
example
using a coil spring 24 mounted concentrically around the shaft 12. The shaft
12 may be
positioned to translate within an axial passage 25 through the pressure plate
16, for example
between ends 32 of the spool 30. A handle 26, such as a plate 27 as shown, may
be mounted
to the shaft 12. The ends 33 of the spring 24 may be mounted around, on, or
within
respective nipple sleeves 37 and 39 located on flanged end 32 and handle 26,
respectively.
Other spring connection mechanisms may be used. Under normal operation a
spring 24 may
be selected to have a spring constant, shape, and size sufficient to retract
the blades 14
against pressure plate 16 when in a neutral position and not subject to
external forces from a
user's hand, or a tile 21 for example. A user (not shown) may extend the
blades 14 into a tile
receiving or extended position (Fig. 1) by squeezing the handle 26 and spool
30 together,
compressing the spring 24.
[0027] The handle 26 may be mounted to incrementally translate along the
shaft 12
to adjust pressure on the pressure plate 16. One mechanism to permit
incremental translation
is to thread the handle 26 to the shaft 12 using a threaded connection 28. A
threaded portion
47 of shaft 12 may extend to a torque transfer portion 49 of the shaft 12. A
user may
effectively load or unload the spring 24 by threading and unthreading,
respectively, the
handle 26 along the shaft 12. If the handle 26 is advanced to compress the
spring 24, when
the spool 30 and handle 26 are released, the increased loading on the spring
24 imparts a
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relatively larger clamping force between blades 14 and pressure plate 16, as
discussed further
elsewhere in this document. Loading the spring 24 applies controlled, positive
pressure
beyond that of the spring 24 in the neutral position. Other suitable
mechanisms of connecting
the handle 26 to the shaft 12 may be used.
[0028] The threaded portion 47 may have an outer diameter (OD) equal to or
smaller
than a maximum OD of torque transfer section 49, to permit the shaft 12 to be
inserted
axially into spool 30 from the base of the spool. An appropriate thread
spacing may be
selected to tailor the advancement speed of thread. For example, a standard
coarse thread on
a bolt may be used or adjusted to provide a faster or slower advancement per
turns of handle
26. For example, a thread rate may be selected to provide a full stroke from
maximum to
minimum displacement with one 360 degree turn. A faster advancement rate
carries a
proportional increased torque requirement, so torque requirement versus
advancement rate
may be balanced in selecting a desired rate.
[0029_1 Referring to Figs. 1 and 4, a torque transfer connection 42 may be
between
the pressure plate 16 and the shaft 12. The torque transfer connection 42
permits the pressure
plate 16 and shaft 12 to translate axially relative to one another, while
locking the two parts
rotationally together. The torque transfer connection 42 shown comprises a
spline to spline
connection, for example a pair of mating series of splines 44 and 46,
respectively, of the
pressure plate 16 and shaft 12. The series of splines 44 and 46 may be
contoured axially
along a torque transfer portion 48 of the pressure plate 16 and a torque
transfer portion 49 of
the shaft 12, respectively. Referring to Figs. 4B and 4C, other suitable
torque transfer
connections may be used, for example a keyway 50 and key 52 connection (Fig.
4B), and a
lateral pin 54 and axial slot 56 connection (Fig. 4C). Referring to Fig. 4B,
the right hand side
of the dashed line illustrates a keyway 50 that may itself form a female
spline mated to the
key 52, which forms a male spline. The left hand side of the dashed line
illustrates the key 52
as an axial pin located in keyways 50 on the shaft 12 and pressure plate 16.
Referring to Fig.
4C, a lateral pin 54 may be anchored through a lateral bore 55 in the shaft
12, engaging an
axial slot 56 channeled along a torque transfer portion (not shown) of the
pressure plate 16.
[0030] The blades 14 may define knife edges contoured for cutting through
unset or
partially but not fully set mortar 58. Referring to Fig. 5, each of the
opposed blades 14 may
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have a knife edge 60 facing one of a counter-clockwise or clockwise direction
of rotation, in
this case the counter-clockwise direction of rotation 62. Each of the opposed
blades 14 may
also have a side wall 64 facing the other of a counter-clockwise or clockwise
direction of
rotation, in this case the clockwise direction of rotation 66. The direction
of rotations are
defined from the perspective of a person looking down a shaft axis 63 from the
handle end
18.
[0031] Side walls 64 and knife edge 60 may alternate as leading and
trailing edges on
insertion and removal of the device 10. For example, when rotating the shaft
12 clockwise to
position the blades 14 under tile (not shown), as discussed further below, the
side walls 64
may form the leading edge. The side walls 64 may have a face oriented
perpendicular to the
direction of rotation 66, thus forming a blunt object that acts to displace
unset mortar and
create a void (not shown) in the wake of the blades 14. When rotating the
shaft 12 counter-
clockwise to remove the blades 14 from under the tile (not shown), the knife
edges 60
become the leading edge, passing through the void and cutting through
partially set mortar
that may have partially filled the void or that is present within the path of
the blades 14. The
arrangement of knife edges 60 and side walls 64 may be reversed for example
for left-
handed users, and in some cases side walls 64 are replaced with knife edges 60
or vice versa.
Terminal tips 65 of each blade 14 may also form knife edges (not shown).
[0032] The components of tile alignment device 10 may be made from suitable
materials. For example, plastic, steel, wood, or other materials may be used
with sufficient
integrity to withstand the clamping, torqueing, and spring forces exerted
between
components. Components may be made from different materials, for example if
spool 30 and
handle 26 are made of plastic and shaft 12 made of metal. If handle 26 is made
of plastic, a
metal thread shell (not shown) may be provided to prevent stripping of plastic
threads.
[0033] Referring to Figs. 1 -3, a method is illustrated for aligning
adjacent tiles 21.
A mortar bed 58 may be laid, and adjacent tiles 21 positioned on bed 58 before
bed 58 has
set. Referring to Fig. 1, blade end 20 and opposed blades 14 may be inserted
into a gap 84
between side walls 86 of adjacent tiles 21. Prior to insertion, a user may
squeeze handle 26
and spool 30 together to draw the device 10 into the extended position shown,
with a
separation distance 92 between the blades 14 and pressure plate 16 equal to or
greater than a
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thickness 93 of tile 21. The stroke length of the device may be adjusted by
advancing or
retracting the handle 26 along the shaft 12 for thinner or thicker tiles 21,
respectively.
[0034] In order to insert the blade end 20, the device 10 may be rotated to
align a
blade axis 85 parallel with a longitudinal axis 87 of the gap 84, and the
device 10 inserted in
a direction 88 along a shaft axis 63 into gap 84. Insertion may proceed until
blades 14 have
cleared a plane 89 defined by the underside face 90 of the lower or deeper set
of the two
adjacent tiles 21.
[0035] Once in position the opposed blades 14 may be hooked underneath the
adjacent tiles 21. For example while in the extended position the shaft 12 may
be rotated
along direction lines 91 such that the blades 14 assume the position shown in
dashed lines in
Fig. 1, with each blade 14 underlying an underside face 90 of a respective one
of the adjacent
tiles 21. The use of blades 14 instead of a permanent base may reduce the
thickness of the
mortar bed 58 required to be used.
[0036] Referring to Fig. 2, as soon as the blades 14 underlie the tiles 21,
such that
each tile 21 is positioned within a respective tile receiving recess 22, the
adjacent tiles 21
may be clamped between the opposed blades 14 and pressure plate 16. Clamping
may be
carried out by the user releasing the squeeze grip between handle 26 and spool
30, permitting
spring 24 to draw blades 14 towards pressure plate 16, hooking the tiles 21
and drawing
external faces 94 into contact with pressure plate 16 and flush relation with
one another.
While in the clamped position shown, the spring 24 applies constant tension on
shaft 12 and
pressure upon pressure plate 16, maintaining the grip upon the tiles 21. In
some cases,
additional force may be needed to align the tiles 21, for example when using
relatively large
or heavy tiles. In such cases, the handle 26 may be incrementally translated
to increase
spring loading. For example the handle 26 may be rotated along direction lines
61 to thread
the handle 26 further down the shaft 12 to the position shown in dashed lines,
compressing
and loading the spring 24 until tiles 21 are aligned. Downward pressure from a
user, for
example a user's palm, against plate 27 may assist translation by reducing the
torque
required to perform the translation. During translation of the handle plate 27
the pressure
plate 16 may be rotationally isolated from the handle plate 27. Thus, the
pressure pad 16 may
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remain rotationally stationary relative to the handle 26, avoiding imparting
torque on the tiles
21, of which such torque may act to reposition the tiles 21 undesirably.
[0037] The shaft 12 may be provided with a tile contacting portion 96 that
has a
width 97 equal to a desired gap spacing between adjacent tiles 21. Common
spacing widths
include 1/8 and 'A of an inch for example. Once the device 10 is in the
clamped position, or
before clamping but while shaft 12 is inserted within the gap 84, the position
of tiles 21 may
be adjusted to contact shaft 12 with side walls 86. For example, a rubber
mallet (not shown)
may be tapped against an opposing side wall (not shown) to translate one tile
21 toward the
other to close the gap 84. Thus, the shaft 12 may act as a spacer in addition
to an alignment
device. Tile contacting portion 96 may comprise a relatively narrow stem
extended from
torque transfer portion 49 of shaft 12.
[0038] Referring to Fig. 3, at some point after the adjacent tiles 21 are
clamped, the
device 10 is removed from between the tiles 21. in some cases withdrawing is
done after the
mortar 58 has partially set but before full setting has occurred. In one case
the mortar 58 has
set sufficiently if a user is able to walk on the tiles 21 without disturbing
the tile 21
positioning. Removal may be done by withdrawing the shaft 12 and opposed
blades 14
through the gap 84. As part of removing the device 10, the shaft 12 may first
be rotated to
once again align the blade axis 85 parallel with a longitudinal axis 87 of the
gap 84. Knife
edges 60 (Fig. 5) if present may cut through mortar present along the
rotational path of the
blades 14 during rotation. Once aligned, withdrawal may be completed by
pulling blade end
20 out of gap 84 along a direction 99 parallel to the shaft axis 63. Thus, the
entire device 10
may be removed leaving no parts remaining in the mortar 58. Because the entire
device 10
may be removed, the entire device 10 may then be reused on a subsequent job. A
gap100
may be left behind in mortar 58 at the position where blades 14 were formerly
located.
Subsequently grout or other gap filling material may be inserted into tile
gaps 84, filling the
gap 100 and filing the space between the side walls 64 of the tiles 21.
[0039] Referring to Figs. 6-9, further embodiments of a tile aligning
device 10 are
illustrated. In the examples shown, no torque transfer connection 42 is used,
although one
may be used. Without a torque transfer connection the shaft 12 may be rotated
relative to the
pressure plate 16. Referring to Fig. 6, the handle plate 27 is secured to the
shaft 12 via a
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lateral pin 68 passing through aligned lateral bores 69 and 70 in the handle
plate 27 and shaft
12, respectively. The handle plate 27 may form a palm grip. Referring to Figs.
7-9, the shaft
12 may comprise first and second shafts 12A and 12B, with one of the opposed
blades 14
extended from the first shaft 12A and the other of the opposed blades 14
extended from the
second shaft 12B. Providing each blade 14 on its own shaft 12 permits use of
device 10 with
tiles (not shown) of varying thicknesses, such as slate. Referring to Fig. 7,
each shaft I 2A,
12B may be spring mounted to pressure plate I 6, for example by spring
mounting via
respective springs 72 to handle 26, which itself is spring mounted to pressure
plate 16.
Respective springs 72 may be positioned in respective recesses 74 within
handle 26, between
opposed shoulders 75, 76 of the handle 26 and shaft 12A, I2B. Shoulders 76 of
shafts 12A,
12B, may be formed by a bent end 77 of the shafts 12A, 12B, such bent end 77
retained
within a lateral bore or slot 69 in handle 26. A cap plug 78 may be used to
seal the ends of
handle 26. Referring to Fig. 8, a similar version of Fig. 7 is illustrated
without springs 72.
Referring to Fig. 9, an example is shown where the shaft 12 is formed by a
single piece of
bent wire 82.
[0040] The device 10 may be withdrawn before mortar has set. A portion of
the shaft
12 or blades 14 may be left behind in the mortar, for example if the mortar
sets and the
blades 14 cannot be dislodged. For such a case a break point or other
disconnection
mechanism may be provided to permit separation of the device at a point below
a plane
defined by the flush external faces 94 of the adjacent tiles 21. The tiles 21
may be levelled in
addition to being made flush with one another. More than two blades, tines,
fingers, or
prongs 14 may be provided, for example if four blades are provided in a cross
configuration
for hooking the undersides of the corners of four adjacent tiles. Three or
more blades are
possible for other tile configurations.
[0041] Squeezing of handle 26 together with spool 30 is described above to
put the
device 10 into the extended position, but other methods may accomplish
extension, for
example lateral force in some designs may extend the hook. A coil spring 24 is
described but
other springs may be used, including leaf springs, bows, butterfly spring, a
biasing device,
and other elastic objects used to store mechanical potential energy. A motor
may be used to
extend or retract the blade end 20. Incremental translation or advancement may
be achieved
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using suitable mechanisms such as cranks, pulleys, chain and sprocket,
ratchets, wedges,
endless conveyors, and other force transfer devices. Devices 10 may be
connected between
adjacent tiles before positioning the tiles on a mortar bed 58.
[0042] Other suitable mechanisms may be used to connect the handle 26 to
the shaft
12, such as friction fit, welding, and others. A shaft tensioner may be
provided between shaft
12 and pressure plate 16, similar to a bolt tensioner. Passage 25 may extend
part way into
pressure plate 16. Passage 25 may comprise a slot in pressure plate 16. Up,
down, top, base,
and other relative words are not intended to be limited to absolute dimensions
defined with
respect to the direction of gravitational acceleration on the earth. In some
cases the tiles 21
may be located on a wall, ceiling, or other non-horizontal surface.
[0043] Description of a component being located at an end includes locating
the
component at or near the end. The blades 14 may have a suitable propeller
shape for cutting
through and displacing mortar. Device 10 may be used in suitable applications
such as tiling
or paving applications. Mortar comprises a workable paste used to bind
building components
together, and includes adhesive, thinset, concrete, grout and other
cementitious
compositions. A screwdriver connection may be provided to translate the
pressure plate 16
or handle 26 to clamp the tiles 21 together. In some cases no spring is
provided, for example
if spring 24 is removed from the embodiment of Fig. 1, and the handle 26
incrementally
translated to clamp the tiles 21 between pressure plate 16 and blades 14. A
bushing surface
(not shown) may be provided between the necks 37 and 39 to prevent handle 26
and spool 30
from rotationally locking via friction.
[0044] Blades 14 may extend along a common blade axis 85 or may have
parallel but
relatively displaced axes, in case the position of each blade 14 is different
to compensate for
different tile thicknesses. Blades 14 may be non-linear in shape, such as if
blades 14 are
curved upward and resilient to accommodate different tile thicknesses.
Pressure plate 16 may
have a tile contacting surface, for example comprising resilient or flexible
material such as
rubber or foam. The tile contacting surface may have a planar surface. The
blades 14 and
base end 20 may form a three dimensional T-shape. A width of the blade end 20
along an
axis perpendicular to the shaft axis 63 and the blade axis 85 may be equal to
or less than a
width of tile contacting portion 96. Plates 16 and 27 may be disc-shaped. A
cross section of
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the shaft 12 perpendicular to the shaft axis 63 across the torque transfer
portion 49 may have
a polygonal shape. The blades 14 may be integrally connected with the base end
20. Blades
14 may have lateral passages, slots or apertures, to permit the passage of
mortar during
rotation. The shaft 12 may have a circular, square, or other suitable shape in
cross section.
[0045] In the claims, the word "comprising" is used in its inclusive sense
and does
not exclude other elements being present. The indefinite articles "a" and "an"
before a claim
feature do not exclude more than one of the feature being present. Each one of
the individual
features described here may be used in one or more embodiments and is not, by
virtue only
of being described here, to be construed as essential to all embodiments as
defined by the
claims.
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