U.S. patent application number 11/350654 was filed with the patent office on 2007-02-22 for rebar positioner for masonry construction.
Invention is credited to Dean Crowell.
Application Number | 20070039278 11/350654 |
Document ID | / |
Family ID | 37766209 |
Filed Date | 2007-02-22 |
United States Patent
Application |
20070039278 |
Kind Code |
A1 |
Crowell; Dean |
February 22, 2007 |
Rebar positioner for masonry construction
Abstract
A rebar positioner for positioning rebar in concrete masonry
units has a spine having a midsection, a first end, and a second
end. The first end may be partially offset to form a first rest and
the second end may be partially offset to form a second rest. The
positioner includes a ring, which may be bifurcatingly attached to
the spine. The positioner also includes a crossbar attached to the
spine.
Inventors: |
Crowell; Dean; (Wilkesboro,
NC) |
Correspondence
Address: |
MACCORD MASON PLLC
300 N. GREENE STREET, SUITE 1600
P. O. BOX 2974
GREENSBORO
NC
27402
US
|
Family ID: |
37766209 |
Appl. No.: |
11/350654 |
Filed: |
February 9, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60708650 |
Aug 16, 2005 |
|
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Current U.S.
Class: |
52/677 |
Current CPC
Class: |
E04C 5/18 20130101; E04C
5/168 20130101; E04G 21/185 20130101 |
Class at
Publication: |
052/677 |
International
Class: |
E04C 5/16 20060101
E04C005/16 |
Claims
1. A rebar positioner comprising: a spine having a spine
midsection, a first spine end, and a second spine end; a ring
attached to the spine near the spine midsection; and a crossbar
attached to the spine near the spine midsection, the crossbar
having a crossbar midsection, a first crossbar end, and a second
crossbar end.
2. The positioner of claim 1, wherein the first spine end includes
a first rest and the second spine end includes a second rest.
3. The positioner of claim 2, wherein the first rest is offset from
the spine midsection, and wherein the second rest is offset from
the spine midsection.
4. The positioner of claim 3, wherein the first rest and the second
rest are integral with the spine.
5. The positioner of claim 3, wherein the first rest is
substantially inline with the second rest.
6. The positioner of claim 5, wherein the first rest and the second
rest have portions substantially parallel with the spine
midsection.
7. The positioner of claim 1, wherein the ring is bifurcated by its
attachment to the spine.
8. The positioner of claim 1, wherein the crossbar is attached to
the spine at the crossbar midsection.
9. The positioner of claim 8, wherein the crossbar is attached to
the spine at the crossbar midpoint.
10. The positioner of claim 8, wherein the crossbar is
substantially perpendicular to the spine.
11. The positioner of claim 9, wherein the crossbar is in contact
with the ring.
12. The positioner of claim 9, wherein the crossbar is attached to
the spine through the ring.
13. The positioner of claim 1, wherein the positioner is at least
partially formed of metal.
14. The positioner of claim 1, wherein the positioner is at least
partially formed from a group of steel metal wires selected from
the group consisting of 6 gauge, 7 gauge, 8 gauge, 9 gauge, 10
gauge and 11 gauge.
15. The positioner of claim 13, wherein the positioner is at least
partially coated in a rustproof coating.
16. The positioner of claim 13, wherein the positioner has at least
partially been given a rustproof treatment.
17. A rebar positioner comprising: a spine having a midsection, a
first end, and a second end, wherein a part of the first end is
offset to form a first rest and a part of the second end is offset
to form a second rest substantially in line with the first rest; a
ring having a perimeter and attached to the spine near the spine
midsection with portions of the ring on either side of the spine
defining areas sized to receive rebar; and a crossbar attached to
the spine.
18. The rebar positioner of claim 17, wherein the positioner is
sized for positioning rebar in 12'' CMUs.
19. The rebar positioner of claim 17, wherein the positioner is
sized for positioning rebar in 8'' CMUs.
20. The rebar positioner of claim 17, wherein the positioner is
sized for positioning rebar in CMU selected from the group
consisting of 6'' CMU, 10'' CMU, and 14'' CMU.
21. The positioner of claim 17, wherein the ring is substantially
elliptical and has a major and minor axis.
22. The positioner of claim 17, wherein the crossbar is attached to
the spine near the ring.
23. A rebar positioner comprising: a spine having a spine
midsection, a first spine end, and a second spine end; a crossbar
attached to the spine near the spine midsection, the crossbar
having a crossbar midsection, a first crossbar end, and a second
crossbar end; and a ring attached to the crossbar.
24. A method of making a rebar positioner comprising: attaching a
ring to a spine near the spine midsection; and attaching a crossbar
to the spine near the spine midsection.
25. The method of claim 24, further including forming a first rest
on a first spine end and a second rest on a second spine end by
bending the spine to offset the rests from the ring.
26. The method of claim 25, wherein the positioner at least
partially comprises metal.
27. The method of claim 26, wherein the attaching includes
welding.
28. A method of constructing walls comprising: laying a first
course of CMUs so that the CMUs have generally vertically oriented
channels; mounting a rebar positioner having a ring member onto a
laid CMU to provide positions for at least two rebar so that at
least part of the rebar positioner is recessed within the channel;
and laying a second course of CMUs so that a CMU of the second
course has a vertically oriented channel over the first course so a
CMU channel from the first course at least partially aligns with
the CMU channel from the second course and rebar positioned in ring
members can extend through the aligned CMU channels.
29. The method of claim 28, including inserting a first rebar into
one of the ring members.
30. The method of claim 29, further including laying at least a
third course of CMU having a channel.
31. The method of claim 30, further including inserting a second
rebar into another of the positions of the ring member.
32. The method of claim 31, further including pouring concrete into
the channel containing the positioner and rebar.
33. The method of claim 28, wherein the positioner is the
positioner of claim 1.
34. The method of claim 28, wherein the positioner is the
positioner of claim 17.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/708,650, filed Aug., 16, 2005.
BACKGROUND INFORMATION
[0002] In masonry construction, particularly for the construction
of retail buildings, such as big box retailers or drug stores,
sidewalls are typically made of stacked concrete masonry units
(CMUs), commonly called cinder blocks. CMUs are generally
rectangular, right parallelepipeds having peripheral sidewalls and
a central core. Typically the central core includes two channels
extending between the two longer edges of the parallelepiped and
separated a medial wall. During construction, CMUs are stacked by
offsetting the CMUs of odd and even courses so the various channels
of the CMUs align vertically. For example, the left channel of a
CMU in one course is positioned over the right channel of a CMU in
the course above or below. Such staggering, while increasing
stability, also creates relatively continuous vertical channels
extending from course to course. Where the blocks are in contact,
they are joined by mortar to adhere the blocks together.
[0003] To provide reinforcement, reinforcing bars, commonly called
rebar, are extended vertically through the vertical channels, and
concrete is poured into the channel and allowed to set. It is
common at some construction sites to extend such walls to heights
of 30-34 feet. Reaching these heights requires care, however, to
insure that rebar properly positions within the channels and that
concrete adequately flows into the channel. In many cases, rebar
overlapping may be required to reach desired heights or to build
structures of adequate strength. For example, for an 88 inch length
of rebar, the upper 40 inches may be overlapped with rebar above,
and the lower 40 inches may be overlapped with rebar below, leaving
only 8 central inches of rebar without overlapping. Others may use
even more overlapping or less overlapping.
[0004] Such proper positioning, centering and overlapping of rebar
has typically been accomplished using positioners such as
positioner 12 shown in FIG. 1. FIG. 1 shows a CMU 10 with central
channels 11. A z-shaped wire rod 12 includes two lengths 13 joined
by link 15. An oval portion 14 is welded to link 15 in a manner
that bisects link 15. In use, z-shaped member 12 is laid on block
10 and mortar is laid onto on surface 18 of block 10. Rebar 16
extends through one half of oval 14 bisected by link 15. The other
half of oval 14 can receive a second rebar in order to provide
overlapping rebar placement.
[0005] Using traditional positioners however, such as, for example,
the positioner shown in FIG. 1, creates numerous problems. For
example, one of the primary purposes of positioner 12 is to help
retain the position of rebar 16. But, because positioner 12 is
itself prone to excessive movement relative to block 10, requisite
rebar positioning can be difficult. Positioner 12 is prone to
lengthwise movement, or movement in line with the longest side of
the CMU; widthwise movement, or movement in line with the shortest
side of the CMU; and irregular movement, or any diagonal or
additional movement. The instability of positioner 12 is further
exaggerated during mortar application and the application of
additional blocks. And, in some instances, it is necessary to
vibrate blocks or walls under construction during mortar or
concrete application to facilitate concrete migration into block
channels 11. This adds to positioner instability, because such
vibration further results in the movement of the rebar positioners.
In addition to the general positioning problems that can occur as
positioners move generally, another specific problem arises when
positioners move widthwise or irregularly. When positioners move
widthwise or irregularly they have an increased tendency to punch
out mortar on either the exterior or interior portion of the wall.
Such problems require extensive and costly repair.
[0006] Others have overcome some of the aforementioned positioning
problems using grid-like positioners similar to positioner 22 shown
in FIG. 2. Positioner 22 has a pair of widthwise arms 24 positioned
across the width of the block 10 and a pair of bent arms 26
positioned lengthwise and connected to widthwise arms 24. The
positioning of widthwise arms 24 and bent arms 26 creates square
30. Bent arms 26 have a bent portion 32 for contacting the interior
part of channel 11 and increasing positioner stability.
[0007] While positioner systems such as positioner 22 are desirable
for their ability to provide some increased stability, they still
leave several problems unaddressed. For example, while bent arms 26
reduce lengthwise movement, they do not always prevent widthwise
movement. Again, such widthwise instability, in addition to
contributing to general positioning problems also increases the
tendency for mortar punch-out. Such positioners are also
problematic because square 30 typically allows for too much rebar
movement, resulting in further positioning inaccuracies. Even
further still, positioners such as positioners similar to
positioner 22 do not provide two separate positioner portions for
rebar overlapping, which can create additional alignment problems.
Various other positioners have various other shortcomings.
[0008] Accordingly, an improved rebar positioner is needed.
SUMMARY
[0009] The present invention provides an improved rebar positioner.
The rebar positioner includes a spine having a spine midsection, a
first spine end, and a second spine end. Preferably the spine
includes both an integral first spine rest, located at the first
spine end, and an integral second spine rest, located at the second
spine end, for resting the positioner on the CMU. Ideally, the
first and second rests are offset from the spine midsection and
allow the spine midsection to extend into a channel of the CMU.
Preferably, the midsection of the spine can be positioned
downwardly into the channel with a friction fit, but supports
lacking a friction fit are also within the scope of the present
invention.
[0010] The rebar positioner also has a ring, preferably attached to
the spine near the spine midsection. Preferably, the ring is
bifurcatingly attached to the spine, or attached to create two
separate ring portions or rebar aligning portions. Those skilled in
the art would recognize that attachment can be achieved by any
means, such as by welding, clamping or adhesive. Still others may
prefer to cast their positioners as a single item, and such forms
of construction are considered to be attachments for the purpose of
the present invention. Further, while the ring is preferably
elliptically shaped to better conform to and position the rebar,
the ring can be virtually any shape. For example, in other
embodiments the ring may be any number or shape of circles,
squares, rectangles, triangles, rhombuses, hexagons, or trapezoids.
Still, in other embodiments the ring may have an irregular shape,
such as an oval, tear drop, clover, or another shape that is not
well defined.
[0011] The positioner also comprises a crossbar attached to the
spine near the spine midsection. The crossbar has a crossbar
midsection, a first crossbar end, and a second crossbar end. The
crossbar is preferably substantially perpendicular to the spine. In
preferred embodiments, the crossbar is also in contact with the
ring to increase the strength of attachment, yet embodiments that
do not utilize such ring contact are still within the scope of the
present invention. Still, in other embodiments, the crossbar may be
attached to the spine through the ring, rather than attached
directly to the spine, such as, for example, the cross bar contacts
the spine without attachment to the spine. In those embodiments
where the spine midsection is downwardly positioned in the channel
of the CMU, the crossbar, because it is attached near the
midsection of the spine, is also downwardly positioned in the
channel. The crossbar provides widthwise stability, preferably, by
contacting interior walls of the channel. Still in other
embodiments, the crossbar may provide widthwise stability by
contacting other portions of the CMU, or other portions of the CMU
in combination with the interior walls.
[0012] Further, those skilled in the art will recognize that, while
in preferred embodiments the ring is attached to the spine, in
other embodiments the ring may be attached to the crossbar.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention will be better understood from a reading of
the Detailed Description taken together with the Drawings in
which:
[0014] FIG. 1 shows a prior art positioner on a CMU;
[0015] FIG. 2 shows another prior art positioner on a CMU;
[0016] FIG. 3 shows a positioner according to a preferred
embodiment of the present invention;
[0017] FIG. 4 shows the positioner of FIG. 3 positioned on a
CMU;
[0018] FIG. 5 shows a side schematic view of one embodiment of the
invention installed on several courses of CMU reinforced by rebar;
and
[0019] FIGS. 6-10 show other embodiments of the present
invention.
DETAILED DESCRIPTION
[0020] FIG. 3 shows a rebar positioner 38 according to a preferred
embodiment of the present invention. Positioner 38 comprises a
spine 40 having a spine midsection 42, a first spine end 44, and a
second spine end 45. Positioner 38 includes a first spine rest 46
located at first spine end 44 and a second spine rest 47 located at
second spine end 45.
[0021] In the depicted embodiment, both spine rests 46 and 47 are
integral with spine 40. While spine 40 could be constructed of
numerous materials, e.g. various ceramics, plastics, metals and
woods, preferably, spine 40 of the present embodiment is
constructed of nine gauge steel wire. Such wire is ideal because it
facilitates the shaping of the spine and provides the requisite
durability needed for construction. For example, as represented by
FIG. 3, spine 40 is bent at points 50 and 51 to form the spine
rests 46 and 47 and to offset spine rests 46 and 47 from spine 40.
While the integral formation of the spine rests 46 and 47 from the
spine 40 is ideal in terms of cost efficiency, it is not critical,
and others may prefer to construct spines, which contain
non-integral spine rests, or, which contain spine rests made of
different materials. All such variations would be within the scope
of the present invention.
[0022] Positioner 38 also comprises a ring 60, which attaches to
the spine 40 near spine midsection 42. Preferably, ring 60
bifurcatingly attaches to spine 40, or attaches to spine 40 to form
a first rebar aligner 62 and a second rebar aligner 64. In
preferred embodiments, ring 60 is elliptical. However, the ring of
the present invention can be almost any shape, e.g. a circle,
square, rectangle, triangle, rhombus, hexagon, trapezoid, oval, or
teardrop; or any other shape. Further, while ring 60 of the present
embodiment is a continuous ring, discontinuous or broken rings
could be used to achieve the present invention. Preferably, the
opening of the ring is sized to receive rebar easily, yet inhibit
sideways movement.
[0023] Positioner 38 also comprises a crossbar 70, which attaches
to spine 40 near spine midsection 42. Crossbar 70 has a crossbar
midsection 72, a first crossbar end 74, and a second crossbar end
75. Crossbar 70 attaches to spine 40 substantially perpendicularly
to spine 40 and preferably at the approximate crossbar midpoint.
Others may prefer other attachment points on crossbar 70, which
would still be within the scope of the present invention. In this
embodiment, crossbar 70 also attaches to ring 60 for increased
structural strength. Such ring contact is not necessary to achieve
the present invention, and others using other embodiments may
prefer not to attach crossbar 70 to the ring 60.
[0024] The positioner 38 is preferably at least partially formed of
metal and is more preferably substantially 100% formed of metal.
Those of skill in the art would recognize that a positioner may be
substantially 100% formed of a metal, even if various attachment
means used to construct the positioner are non-metals, such as
non-metal adhesives or plastic clips, for example.
[0025] A wide variety of metals are ideal for forming the various
embodiments of the present invention. For example, positioner 38
could be at least partially to substantially 100% formed of steel
metal wires, e.g. six gauge, seven gauge, eight gauge, nine gauge,
ten gauge or eleven gauge wires. Preferably, the positioner is
formed of nine gauge steel wire. In preferred embodiments, the
positioner is at least partially coated with a rustproof coating,
such as a galvanized coating, or has at least partially been given
a rustproof treatment or wash.
[0026] If the positioner is constructed of one material, such as
the preferred 9 gauge wire, assembly cost is minimized and waste is
reduced. Such cost savings can be realized in a number of ways. For
example, because spines, crossbars, and rings can all be purchased
from the same supplier, i.e. the metal or wire supplier, rather
than purchased from separate suppliers, bulk purchasing power
should be recognized. Similarly because of the ease of
manufacturing, those practicing the present teachings may be able
to produce the positioner themselves, thereby eliminating the need
for an additional prefabricator, which results in cost savings.
Further cost reductions arise by virtually eliminating waste
associated with the production process. By cutting metal or wire to
the correct length to form the various components, virtually all
starting material can be used, resulting in increased efficiency
and cost savings. Similarly, by cutting metal or wire to the
correct length to form the various components, there is essentially
no waste produced, thereby reducing costs associated with waste
disposal.
[0027] Others may desire to form positioners of the present
invention out of other materials, such as other plastics, woods, or
ceramics, or out of a combination of other materials and metals.
All such combinations would be within the scope of the present
invention.
[0028] FIG. 4 shows positioner 38 of FIG. 3 on a CMU 10. Positioner
38 rests on the surface 18 of the CMU through rests 46 and 47.
Preferably, rests 46 and 47 are in substantially the same linear
orientation with one another and are in substantially the same
plane, which would be, in this embodiment, the plane of surface 18.
Further, in this embodiment the linear orientation of rests 46 and
47 is substantially parallel to the linear orientation of the
midsection of spine 40. Others may desire to offset the linear
orientation of rests 46 and 47 or may desire to orient rests 46 and
47 in different planes, which would be within the scope of the
present invention. Rests 46 also facilitate positioner 38 insertion
into channel 11.
[0029] Rests 46 allow a portion of spine 40 to extend into channel
11. Preferably the portion of spine 40 for inserting in channel 11
is sized to frictionally fit within channel 11. In this embodiment,
the effects of rests 46 and 47 prevent further widthwise movement
of the positioner. Crossbar 70 also inserts into channel 11 and is
preferably sized to frictionally fit within the interior walls of
channel 11. In this embodiment, crossbar 70 prevents lengthwise
movement of the positioner. The fit of the crossbar 70 also
prevents positioner rotation about the axis of spine 40. Ring 60,
which bifurcatingly attaches to the spine 40, and in this
embodiment, also attaches to the crossbar 70, rests within channel
11. Rebar 80 is shown inserted into second rebar aligner 64 of ring
60. While in this embodiment, the spine 40 orients widthwise, and
crossbar 70 orients lengthwise, others using other embodiments, may
prefer to orient the spine lengthwise and the crossbar widthwise,
which would be within the scope of the present invention. Still in
other embodiments, the crossbar may provide widthwise or lengthwise
stability by contacting other portions of the CMU, or other
portions of the CMU in combination with the interior walls of the
channels of the CMU. Further, other structural embodiments may
include various other ways to span the hollow core or channel of
the CMU and make engagement with the inner side of the hollow core
of the CMU while still retaining contact with the upper face of the
CMU.
[0030] FIG. 5 shows a side schematic view of several courses of CMU
10 with installed embodiments of the positioner and rebar. A
plurality of CMUs 10 are stacked upon one another in courses. A
terminated rebar 80A is positioned by rebar positioner 38A. An
additional rebar 80B can be positioned alongside rebar 80A for the
desired overlap, and a further CMU course can be added. Concrete is
poured into the channels, typically filling four or five courses,
up to grout lift 500. Once that concrete sets, a further course of
CMU (CMU 10A) can be applied and rebar positioner 38B can be
positioned on new CMU 10A. An additional rebar 80C can then be
positioned on the top of the poured concrete, forming the
reinforcement bottom leg for the next series of courses up to the
next grout lift 502. On top of the course (CMU 10B) immediately
below the grout lift 502, a further rebar positioner 38C is put in
place as an overlapper, so that the two rebars overlap and are held
in position by the two rebar positioners 38C and 38B. Then, when
the upper course (CMU 10C) is added and a further grout lift level
502 is added, the process can be repeated. It will be appreciated
that joints between the CMUs are mortared, as is conventional. It
will further be appreciated that by using the preferred
embodiments, the positioner stays in position and holds the rebar
in position centrally within the channel of the CMU, despite the
application of vibration, and throughout the laying of other
courses on the laid course, so that remediation and repair work are
kept to a minimum. Also, the minimal cross section of the preferred
embodiments provides little resistance to the flow of concrete
being introduced into the channel, reducing the likelihood of void
formation.
[0031] FIGS. 6-10 show other embodiments of the present invention.
FIG. 6 shows an embodiment where the ring 660 is attached to the
spine 640 without attachment to the crossbar 670. FIG. 7 shows an
embodiment where two rings 760 are used to increase the number of
rebar positioning options, which could be used to provide increased
rebar overlapping, for example, to construct taller structures or
to construct more stable structures. FIG. 8 shows an embodiment
where the ring 860 surrounds the intersection 820 of the spine 840
and the crossbar 870. Such an embodiment could be used to increase
the number of rebar aligners from two to four without requiring an
additional ring. FIG. 9 shows an embodiment where the ring 920
attaches to the crossbar 970. FIG. 10 shows an embodiment where two
rings 940 attach to the crossbar.
[0032] Those skilled in the art will recognize that CMUs are
manufacture primarily in standard sizes, such as 6'', 8'', 10'',
12'', and 14'' sizes, and also come in custom, nonstandard, or
miscellaneous sizes. For any size of CMU, standard or otherwise,
the present invention may be achieved using a variety of
dimensions, but some dimensions may be preferable.
[0033] For example, for positioners for positioning rebar in 12''
CMUs, preferably, the positioner has a spine length of between
about 8'' to about 12'', and more preferably has a length of about
10- 12/16''. The positioner has a spine midsection length of
between about 7'' to about 9'', preferably about 8-1/8''. The
positioner also preferably includes first and second spine rests,
which have a length of between about 1 inch to about 2 inches, and
preferably have a length of about 1- 5/16''. The crossbar has a
length from between about 6'' to about 8'', and preferably has a
length of about 7''. The ring is preferably substantially
elliptical and has a major axis between about 2'' and about 4'',
more preferably about 2-1/2''; and has a minor axis between about
1/2'' and about 2'', more preferably about 1''. In alternate
embodiments, the position of the crossbar on the spine varies and
can be adjusted to accommodate various ring sizes or to accommodate
two or more rings. For example, for embodiments using only a single
ring, the crossbar may be positioned to be about 3- 7/16'' off the
interior of the CMU channel wall, with the ring approximately over
the midpoint of the spine. If two rings are used, however, each
ring may be positioned to be about 2-1/2'' off the interior of the
CMU channel wall, with the crossbar approximately over the midpoint
of the spine.
[0034] Similarly, for positioners for positioning rebar in 8''
CMUs, preferably, the positioner has a spine length of between
about 5'' to about 7'', and more preferably has a length of about
6- 12/16''. The positioner has a spine midsection length of between
about 3'' to about 6'', preferably about 4-5/8''. The positioner
also preferably includes first and second spine rests, which have a
length of between about 1 inch to about 2 inches, and preferably
have a length of about 1- 5/16''. The crossbar has a length from
between about 4'' to about 6'', and preferably has a length of
about 5''. The ring is preferably substantially elliptical and has
a major axis between about 2'' and about 4'', more preferably about
2-1/2''; and has a minor axis between about 1/2'' and about 2'',
more preferably about 1''. In the preferred embodiments, the
position of the crossbar on the spine varies and can be adjusted to
accommodate various ring sizes or to accommodate two or more rings.
For example, for embodiments using only a single ring the crossbar
may be positioned to be about 1-1/2'' off the interior of the CMU
channel wall, with the ring approximately over the midpoint of the
spine. If two rings are used however each ring may be positioned to
be about 7/8'' off the interior of the CMU channel wall, with the
crossbar approximately over the midpoint of the spine.
[0035] Those skilled in the art will be able, using proportions
determined from the dimensions provided or other dimensions, to
create various embodiments for any number of CMU sizes.
[0036] Numerous characteristics and advantages have been set forth
in the foregoing description, together with details of structure
and function. The novel features are pointed out in the appended
claims. The disclosure, however, is illustrative only, and certain
modifications and improvements will occur to those skilled in the
art upon reading the foregoing description. It should be understood
that all such modifications and improvements have been omitted for
the sake of conciseness and readability, but are properly within
the scope of the following claims.
* * * * *