Note: Descriptions are shown in the official language in which they were submitted.
VERTICAL CONTROL JOINT GROOVER
FOR CONCRETE ONSTRUCTIONS
I. DESCRIPTION
BACKGROUND OF THE INVENTION
Control joints in concrete slabs provide for
differential movement in the various planes thereof, and
are used to allow for contraction caused by drying
shrinkage therein. If no control joints are used in slabs
on the ground or in lightly reinforced walls, random
cracks will occur when drying shrinkage produces tensile
stresses in excess of the concrete's tensile strength.
There is a definite need for a method and/or
device for efficiently providing a desired vertlcal
control joint to the vertical face of various concrete
constr~uctions, such as concrete steps, curbs; slabs, etc.
The conventional~ way of constructing concrete structures
is to first build a wooden form in the shape and
dimensions of the desired concrete construction. Into
such a form the concrete i3 poured while still in soft
condition, the concrete taking the shape of the form's
interior, which is the desired shape, and thereby defining
the concrete construction.
~s the concrete commences to set and harden, the
horizontal upper edges thereof ~are radiused with
conventional tools, while the vertical faces thereof are
relatively inaccessible because of the presence of the
surrounding wooden orm. If any joints are to be formed
in the top surface of the concrete slab within the form,
such are induced in the upper surface of the slab as it
hardens. The horizontal edges of the concrete slab are
radiused with a conventional radiusing tool just prior to
the hardening of the concrete slab.
only when the slab has hardened sufficiently to
maintain its desired form, can the wooden form be removed
It is at this point thak the wooden form is conventionally
removed and thereafter the attempts to groove the vertical
control joints into the vertical faces of the concrete
construction are made.
~t this point, the concrete is necessarily fairly
well hardened and it is difficult, if not virtually
impossible to shape all of the vertical control joints
before they have reached a degree of hardness such that
they are no longer readily shapable. This is particularly
true when difficultly is experienced with one of the
vertieal control joints because of a rock or other form oE
aggregate being located at that very spot, which requires
removal or repair work. By the time such repair work on
one of the control joints is completed, the remainder of
the concrete construction has frequently hardened to a
condition which makes proper repair or shaping of the
remaining control joints impossible. As a consequence,
shaping vertical control joints into concrete
constructions such as concrete slabs, steps and curbs is a
diEficult and reoccurring problem which is difficult,
time-consuming, and expensive to ovexcome, and often
results in an unsatisfactory and ill-appearing vertical
face.
My new vertical grooving tool obviates the
problem frequently experienced when the concrete along the
vertical face of a concrete construction becomes too hard
to be properly shaped with vertical control joints
therein, because one of the other vertical joints was
difficult to properly shape or repair. My invention is
designed to overcome this problem and to solve it in a
practical, inexpensive, and superior manner, so that the
resultant product is superior in construction and
appearance and is less expensive and time-consuming as
compared to those formed through the use o~ conventional
methods and grooving devices.
BRIEF SUMMARY OF THE INVENTION
My new vertical groover is constructed so that it
can be used in a practical manner to shape vertical
control joints into the ~vertical face of concrete
constructions such as curbs, slabs and steps while the
wooden form surrounding the concrete construction is still
in place. As such, the vertical control joints can be
formed in the concrete construction while the concrete is
still in a sufficien~tly soft and shapeable condition so as
to cause the concrete to readily shape to its desired
orm.
My vertical groover is an elongated at least
semi-rigid forming blade or former which is generally
triangularly shaped in cross-section and elongated so that
it can be inserted downwardly between the concrete
construction and the wooden for~i which surrounds the same.
The generally triangular shaped former is deined by a
pair of opposite side portions which extend angularly
relative to each other and converge at their lower
terminal portions to define a ~oint-forming apex that
extends the length of the former. The upper terminal
portion of each side portion curves slightly outwardly to
deEine a concrete radiusing flange which runctions to
radius the respective outer corner o the vertical control
joint which is formed thereby. This provides an
attractive, finished look to the vertical control joint.
Facing opposite the joint forming apex, and
spaced therefrom, is a substantially flat guiding surface
which extends between opposite radiusing flanges of the
tool. Each radiusing flange tapers smoothly into the flat
guidin~ surface of the former so as to provide a finished
appearance and avoid unsightly ridges in the resulting
concrete construction.
The forward end of the former, which is inserted
downwardly into the concrete construction, is beveled so
as to define a forward parting edge which aids in the
tools insertion within the concrete by causing the
concrete to spread as the tool is inserted therein.
Cantilevered from the rear end of the vertical control
joint former is a shank carrying a handle member, which
may be easily gripped to provide insertion of the groover
quickly and efficiently~ while the concrete is still in
sufficiently soft and shapeable form.
Upon inserting the forward end of the former
downwardly between the concrete construction and the
vertical interior face of the wooden form surrounding the
same, the flat guiding surface is disposed in abutting
relation with the vertical ace of the form, and the joint
forming apex extends inwardly into the concrete
construction so as to part the same and form a vertical
control joint while the concrete is still suficiently
soft and shapeable. Upon inserting the tool between the
wooden form and the concrete construction, the curved
radiusing flanges of the former cause the outer corners of
the vertical control~joint to have an attractive radiused
appearance which lB aesthetically pleasing to the eye.
By moving the vertical groover up and down
gently, tbe tool can be caused -to proceed to the lower end
of the vertical face of the concrete construction, and the
groover's joint forming apex can be caused to shape the
vertical control joints in the concrete construction while
the form remains in place. When this operation has been
completed and each of the vertical control joints have
been formed, the wooden form surrounding the concrete
construction may remaln in place until the concrete has
hardened to such an extent that the form may be removed
without concern that the concrete faces may shift or
otherwise alter their shape.
We have Eound that if this tool is applied and
manipulated as described when the concrete has reached the
appropriate degree of ~irmness, a well defined, attractive
vertical control joint can be produced on the vertical
face of concrete constructions such as curbs, slabs and
steps. A substantial amount of time and effort are
thereby conserved and the resultant product is much
stronger and attractive than when formed in the
conventional manner as heretofore utilized.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the
invention will more fulIy appear from the Eollowing
description, made in connection with the accompanying
drawings, wherein like reference characters refer to the
same or similar parts throughout the several views, and in
which:
Fig. 1 of the drawings herein is a perspective
~0 view of a portion of a concrete slab which is encased with
a standard type form, showing in phantom an example of a
.
.
position where a vertical control joint may be necessary
to prevent random cracks as a result of the contraction of
the concrete caused by drying and shrinkage;
Fig. 2 i3 a perspective view of one of my new
vertical groovers;
Fig. 3 is a front elevational view of one of my
new vertical groovers;
Fig. 4 is a cross-sectional view of one of my new
vertical groovers which forms a l/2 inch wide by l inch
deep vertical control joint;
Fig. 5 is a cross-sectional view of one of my
vertical groovers which forms a 7/8 inch wide by 3/4 inch
deep vertical control joint;
Fig. 6 is a cross-sectional view o one of my
vertical groovers which forms a 3/8 inch wide by 3/4 inch
deep vertical control joint; and
Fig. 7 is fragmentary horizontal sect`ional view
taken through one of my new vertical groovers, and showing
a cement slab with the form therearound with my vertical
groover inserted so as to form a vertical control joint
therein.
DETAI~ED DESCRIPTION OF THE INVENTION
As shown in Fig. 2-6 inclusive, my new vertical
control joint grooving tool comprises a handle member 10
supporting a shank member; 11 which extends forwardly and
downwardly therefrom and terminates in an elongated at
least semi-rigid straight former 12 which extends
.
forwardly therefrom a preferable distance of approximately
twelve (12) inches, and which has a cross-sectional
configuration which is generally triangular in shape~ The
former 12 may be made of metal, plastic, or any other
rigid or semi-rigid material.
~3 shown in Fig. 2, preferably the shank member
11 extends upwardly and rearwardly from the former 12 at
approximately 110, and handle 10 extends upwardly and
rearwardly from shank member 11 at an angle of
approximately 50. Although not shown in the drawings, it
is readily apparent that the shank member 11 and handle 10
may also project rearwardly from the former 12 in a
plurality of other orientations, so long as the vertical
groover may be gripped and used by a workman without
disturbing the semi-hardened cement construction with
his/her hand.
As shown in Figs. 4-6, the ~former 12 has a
generally triangular cross-sectional shape which is
defined by a pair of opposite side portions 13 and 14,
which are disposed angularly to :one another and converge
toward the bottom terminal portion:thereof to define a
vertical control joint forming apex or edge 15 that
extends throughout the length of former 12. The upper
terminal portion of each side portion 13 and 14 are
radiused so as to curve slightly outward and form small
cement radiusing flanges 16 and 17, which provide
attractive radiused outer cor~ers of the vert.ical control
joints~formed thereby.
Facing opposite the joint forming apex 15, and
spaced upwardly therefrom ~as illustrated in Figs. 2-6),
is~a substan-tially flat guiding surface 18 which extends
laterally across the groover 12 so as to interconnect the
opposit~ radiusing flanges 16 and 17 theFeof. Each
radiusing flange 16 and 17 is construc-ted so as to taper
smoothly into -th~ flat guiding surface 18 of the former
12, thereby defining a fine finishing edge therebetween.
As shown best in Figs. 2 and 3, side portions 13
and 14 of groover 12 taper inwardly at the forward end 22
of former 12 to form a 4eveled concrete parting edge 19,
which aids in separating the concrete as a tool is
inserted therein.
Although it is conceivable to manufacture
vertical groovers of this type in many different sizes and
dimensions, Figs. 4-6 illustrate groovers which will form
some of the more common sized vertical control joints.
Fig. 4 discloses a 1/2 inch wide by 1 inch deep former;
Fig. 5 discloses a 7/8 inch wide by 3/4 inch deep former;
and Fig. 6 discloses a 3/8 inch wide by 3/4 inch deep
former. The width of former 12 is generally measured
between points adjacent the central portion of -the radius
o~ the opposite radiusing flanges L6 and 17. The depth of
former 12 is measuxed between the flat guiding surface 18
and the joint forming apex lS thereof. -
~,
As illustrated best in Figs. 1 and 7, my vertical
groover is intended for use with concrete constructions
such~as slabs, curbs and steps, wherein the concrete C has
been poured into an exterior form ~F and allowed to set
until the concrete reaches a semi-hardened, but yet soft,
pliable and shapeable condition.
As shown in Fig. 1, the horizontal control joint
20 may be formed by conventional means, but formation of a
vertical control joint while the form is still intact and
the concrete is relatively so~t is extremely difficult,
given that the vertical ~ace of the concrete slab is
inaccessible. ~ For illustrative purposes, the position of
a desired vertical control joint is shown in phantom in
Fig. `I, and designated as numeral 21.
As shown best in Fig. 7, in use, my tool is
utilized by inserting, from above, the forward end 2Z
of the former 12 downwardly into the semi-hardened
concrete slab C at point 21 immediately adjacent to the
inside surface of form F. My vertical groover is
orientated such that the flat guiding surface 18 of former
12 enters the concrete in abutting relation with the
inside surface of form F, thereby causing the oppositely
facing joint forming apex 15 to extend inwardly into the
concrete slab C. ~s former 12 is inserted within the
concrete, parting edge l9 at the forward end 22 thereof
pushes the concrete aside so as to aid in the insertion of
the tool.
The workman applying my vertical groover 9 while
grasping its handle, can effect its entry without
seriously disturbing the concrete by reciprocating -the
tool gently in a vertical direction. The parting edge l9
will aid in the tool's entry, and as former 12 descends,
the shapeable concrete is formed or shaped along its
vertical face so as to define a vertical control joint
therein. As described previously, and shown in Fig. 7,
the resulting vertical control joint will have smoothly
~5 radiused outer corners~ 23 and 24 which give the resulting
vertical control joint an attractive and aesthetically
pleasing finished appearance~
Upon reaching the lower end of the vertical face
of the concrete slab C, the former 12 may be withdrawn
gently so as to allow the concrete to set, while retaining
the vertical control join-t which has been efficiently
formed therein. The result is a better and stronger
finished product, wlth a better appearance.
.
As described previously, conventionally shaping
such control joints could not be formed until after the
concrete had sufficiently hardened to allow removal of the
exterior forms therefor. At such time, the concrete has
hardened to such an extent that oftentimes the workrnan
must attempt to form such control joints with much haste,
thereby leaving many vertical control joints inadequately
formed and ill-appearing. Should repair work be necessary
on any particular control joint, the time required
therefor may jeopardize proper forma-tion of the remaining
control joints which must necessarily be formed.
With my tool, the vertical control joints may be
formed while the concrete is still soft and pliable, and
while the form F remains in place. The tool may be
inserted and worked between the form and concrete while it
is still soft, thereby alleviating the necessity for mueh
repair work and providing a better appearing, stronger and
more finished product in the end.
:
It will, of course, be understood that uarious
~0 changes may be made in the form, details, arrangement and
proportions of the parts without departing from the scope
of the invention which comprises the matter shown and ::
described herein and set forth 1n the appended claims.
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