CAPTURED CLAMP FOR WALLFORM PANEL

PINCE PRISONNIERE POUR PANNEAU DE COFFRAGE DE MUR

English Abstract

A wallform panel is disclosed which includes a
series of captured clamps which can be locked within the
panel in a storage position. The clamps are easily moved
to allow clamping of abutting panels during assembly of
wallform panels. The clamp has a shank and a handle where
the handle provides a mechanical advantage for rotating the
shank. Rotation of the shank allows camming faces to
engage opposed side rails of wall panels and lock them
together.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A wallform system comprising a plurality of wallform
panels; each wallform panel comprising a perimeter frame
supporting a concrete facing substrate, said perimeter frame
including side rails extending generally perpendicular to
said concrete facing substrate, each side rail having a
series of securing slots for cooperation with securing slots
of other wallforms when brought into abutting alignment
therewith, some of said securing slots having an attached
clamping member aligned with the respective securing slot
and movable from a storage position secured within said
perimeter frame to a position for engaging an adjacent side
flange of an aligned abutting wallform panel, said clamp
comprising a shank having interior and exterior opposed
camming members spaced to tightly engage two side rails of
abutting aligned wallforms therebetween, said shank having a
connected handle for rotating said shank about a
longitudinal axis thereof, said slots in one position of
said handle aligning said exterior camming member to pass
through said slot and to pass through an aligned slot of an
abutting aligned wallform and thereafter to cause said
camming members to engage said side rails and clamp said
wallforms by using said handle to rotate said shank to a
clamping position with said camming members clamping said
side rails.
2. A wallform system as claimed in claim 1 wherein said
camming members engage said side rails when said handle is
rotated in either direction about said shank.
3. A wallform system as claimed in claim 1 wherein said
handle when rotated to said clamping position also engages
and clamps said side rails at a different location on said
side rails.
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4. A wallform system as claimed in claim 3 wherein each
clamp is movable to a retained storage position within said
perimeter frame for transportation or storage of the
wallform panel.
5. A wallform system as claimed in claim 3 wherein said
handle in said storage position releasably locks with said
side rail and thereby retains said clamp within said
perimeter frame.
6. A wallform system as claimed in claim 5 wherein said
exterior camming member in said storage position engages and
presses against said side rail.
7. A wallform system as claimed in claim 6 wherein said
securing slots are keyhole slots.
8. A wallform panel comprising a perimeter frame
supporting a concrete facing substrate, said perimeter frame
including side rails generally perpendicular to said
concrete facing substrate, each side rail having a series of
securing slots for cooperation with like securing slots of
similar wallforms, some of said securing slots each having
an attached clamping member cooperating therewith and
movable from a storage position secured within said
perimeter frame to a clamping position for engaging an
adjacent side rail of a an adjcent wallform panel, said
clamp comprising a shank having interior and exterior
opposed camming members spaced to tightly engage two opposed
side rails of adjacent aligned wallform panels therebetween,
said shank having a connected handle for rotating said shank
about a longitudinal axis thereof and for limited movement
of said shank along the longitudinal axis thereof, a
support arrangement for said shank within said perimeter
frame to accommodate said rotation of said shank and limited
sliding movement along the axis thereof, said slots in one
position of said handle aligning with said exterior camming
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member to allow said exterior camming member to pass through
said slot and to pass through an aligned slot of an adjacent
wallform panel and thereafter with movement of said handle
to rotate said shank cause said camming members to engage
and clamp said opposed side rails.
9. A wallform panel comprising a rectangular frame
defined by four side rails with a concrete engaging face
within said frame and at one side thereof, each side rail
having a series of keyhole securing slots spaced in the
length of said side rail for aligning with keyhole securing
slots in side rails of similar wallforms, at least some of
said keyhole securing slots having an associated clamping
member for cooperating with the respective keyhole securing
slot to effect clamping of abutting wallform panels, said
clamping member comprising a shank held within said
perimeter frame with a free end thereof aligned with said
keyhole slot and movable to extend through said keyhole
securing slot, said shank at said free end having an
exterior cam face and an interior cam face spaced in the
length of said shank for engaging therebetween the side rail
of the wallform panel and a side rail of an abutting
wallform panel; said shank including a lever handle for
rotating said shank to a first position where said cam faces
are within said perimeter frame and said exterior cam face
is aligned with said keyhole securing slot for passing
therethrough, said shank being slidable from said first
position to cause said free end and said exterior cam face
to pass through said keyhole securing slot, whereafter said
shank can be rotated about the longitudinal axis thereof to
a clamping position.
10. A wallform panel as claimed in claim 9 wherein said
clamp is movable to a storage position within said perimeter
frame.
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11. A wallform panel as claimed in claim 9 wherein said
handle includes two opposed clamping surfaces which engage
and clamp a rear edge of said side rail when said clamp is
in the clamping position.
12. A wallform panel comprising a perimeter frame
supporting a concrete facing substrate, said perimeter frame
including side rails generally perpendicular to said
concrete facing substrate, each side rail having a plurality
of securing slots for aligning with securing slots of
adjacent abutting wallforms, a plurality of clamps attached
to said wallform, each clamp being associated with one of
said securing slots, each clamp being movable from a storage
position wherein said clamp is secured within said perimeter
frame of said wallform, to an engagement position wherein
said clamp extends through the associated securing slot for
engaging the perimeter frame of an abutting wallform panel,
each clamp including a shank having interior and exterior
opposed camming members which are spaced to tightly bind two
side rails therebetween when said clamp is in an engagement
position, said clamp including a handle connected to said
shank for rotating said shank about a longitudinal axis
thereof between an aligned position allowing said exterior
camming member to pass through said securing slot to said
engagement position, causing said interior camming member to
tightly engage said side rail adjacent said securing slot.
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Description

2179084
WH-9574CA
,._
TITLE: CAPTURED CLAMP FOR WALLFORM PANEL
FIELD OF THE INVENTION
The present invention relates to concrete wallform
systems, and in particular relates to a concrete wallform
panel having a captured securing clamp for securing two
adjacent wallform panels.
BACKGROUND OF THE INVENTION
Concrete wallform systems are now well known and
some of these systems are based on connecting rectangular
wallform panels to define a particular wailform.
Wallform panels, and in particular hand set panels
have used various different types of clamping arrangements
for securing panels in an aligned manner. Specialized
clamps are used which are often in the form of a bolt and
wedge member which pass through aligned slots in the side
rails of wallforms and the wedge is then driven into a port
to draw the two wallforms into abutment. These clamps work
satisfactorily, however, they can get lost on the job site
and the contractor is either charged for this loss or must
replace these devices. Furthermore, the securing
arrangements are not always available when the wallforms
are brought into alignment.
A securing arrangement which is fast and secure is
highly desirable, as it allows a fast connection of panels
as well fast separation of the panels for setup and
storage.
SUMMARY OF THE INVENTION
A wallform panel according to the present invention
has a captured clamp which remains secured to the wallform
panel and is available when the wallform panel is connected
to an adjacent panel. The captured clamp, in a preferred
embodiment, also locks in an interior location within the
wallform to reduce the possibility of damage to the clamp
when the wallform is stored.
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WH-9574CA 2179084
~-
A wallform panel according to an aspect of the
present invention comprises a perimeter frame supporting a
concrete facing substrate. The perimeter frame includes
side rails generally perpendicular to the concrete facing
substrate. Each side rail has a plurality of securing
slots for aligning with like slots of abutting wallforms to
be secured. The wallform includes a plurality of clamps
attached to the wallform with each clamp being associated
with one of said securing slots. Each clamp is movable
from a storage position wherein said clamp is secured
within said perimeter frame to an engagement position
wherein said clamp extends through the associated slot for
engaging an abutting wallform panel. Each clamp includes a
shank having interior and exterior opposed camming members
which are spaced to tightly bind two side rails
therebetween when the clamp is in an engagement position.
The clamp also includes a handle connected to the shank for
rotating the shank about a longitudinal axis thereof
between an aligned position allowing said exterior camming
member to pass through a slot of an adjacent side rail to
said engagement position causing said interior camming
member to tightly engage said side rail adjacent said slot.
According to a preferred aspect of the invention,
the clamping member includes two additional camming
surfaces for engaging the side rails of abutting wallforms
adjacent a rear edge of the side rails.
According to a further aspect of the invention, the
clamp is designed for rotation in either direction about
said shank to cause gripping of two opposed side rails.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are shown in
the drawings, wherein:
Figure 1 is a partial perspective view showing two
abutting side rails of abutting aligned wallform panels;
Figure 2 is a side view showing the clamping member
in a securement position;
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WH-9574CA 217 9 0 8 4
,.._..
Figure 3 is a top view showing two abutting side
rails with the clamping member in a securing position;
Figure 4 shows the clamping member in a storage
position within one wallform panel;
Figure 5 shows connection of three wallform panels;
and
Figure 6 is a side view showing a side rail of a
wallform panel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A panel based concrete wallform system 2 is shown
in Figure 6 where three wallform panels 4 are shown in an
abutting configuration. Each wallform panel 4 has a
perimeter rectangular frame 6 defined by connected side
rails 8. The side rails 8 are adapted to abut and
cooperate with side rails of adjacent wallform panels.
Figure 1 shows portions of two abutting wallform
panels 4 about to be interconnected by means of the clamp
20. The side rails 8 of each wallform panel 4 have a
plurality of securing slots 10. These securing slots are
of a nonsymmetrical nature and the preferred keyhole type
slot shown is preferred. It can be seen that these
securing slots 10 are positioned at a host of standard
positions in the length of each side rail 8 to allow a host
of offset modular positions to be achieved, such as shown
in Figure 5. Furthermore, the portion of the slot to allow
the exterior camming face to pass through is positioned
close to the rear edge of the side rail. This central
position allows rotation of the shank in either direction
for clamping and also maintains strength of the side rail
at the front face.
Each wallform panel 4 has a concrete facing
substrate 12 located within the perimeter frame and
typically supported from behind. In the case of the side
rails 8, they include a number of tabs 14 which extend
inwardly and support the substrate 12 at the rear thereof.
Typically, the tabs can include a port for allowing a screw
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WH-9574CA 2179084
to pass through the tab and into the substrate 12. Other
securing arrangements are possible.
The side rails 8 preferably have a front abutment
flange 50, a rear abutment flange 52 and a recessed locking
web 54. When two side rails are brought into abutment, as
shown in Figure 1, these flanges and recessed webs
cooperate to define the spring gap 56 between the opposed
recessed locking webs 54.
The clamping member 20 is retained within the
perimeter frame 6 by a bracket 16 secured to the wallform
panel. The bracket 16 includes a keyhole port 18 through
which the clamping member extends. The clamping member 20
includes a handle portion 26 and a shank 22. The shank 22
includes interior camming face 24 and an exterior camming
face 25 provided at a free end of the shank 22. The clamp
20, as shown in Figure 1, is about to draw the locking webs
54 of the opposed wallform panels towards each other and
force the abutment flanges 50 and flanges 54 into tight
engagement. This reduces the seam in the face of the
concrete caused by the junction of flanges 50 The side
rails of the wallform panels have been positioned to align
securing slots 10 and the handle has been rotated such that
the camming face 25 can pass through the aligned slots 10.
The clamp is moved such that the shank 22 now extends
between the two side rails 8 with the interior camming face
24 located to the interior surface of one side rail and the
exterior camming face 25 located to the interior of the
opposed side rail. The handle is then rotated about the
longitudinal axis of the shank by forcing the handle in the
direction of arrow 45. This rotation of shank 22 causes
camming faces 24 and 25 to progressively engage the opposed
recessed locking webs 54 and draw the opposed rails into
tight engagement. Each of these locking webs can flex
somewhat and forms a tensioned state due to engagement with
the camming faces. This provides a tight joint 60 between
the wallform panels and thus reduce any seams between the
wallform panels. It can also be appreciated that the rear
faces of the side rails are brought into engagement and a
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WH-9574CA 2179084
'~.
further clamping of the side rails is achieved as the free
end of the handle includes opposed locking slots 28 and 30
which engage the rear edge of the side rails at a position
on the side rails somewhat distant from the shank 22. This
is clearly shown in Figure 3. This further enhances the
securement of the side rails.
From Figure 1, it can be appreciated that although
the handle is shown as rotating in the direction of arrow
45, it could be rotated in the opposite direction about the
longitudinal axis of the shank 22 and engage the side rails
with slot 28 at a position, in this case, above the
position of the shank 22. This may be desirable depending
upon the amount of shift between panels and the location of
other clamps.
The shank is retained within the frame as it is
captured between the handle 26 and a locking pin 40.
Either the locking pin 40 or the interior cam face 24
strikes the bracket 16 such that the clamp cannot be
removed.
Figure 3 illustrates how the locking pin 40 engages
bracket 16 while maintaining the free end 41 of the shank
generally within the side rail 8. In this way, the shank
is always aligned with the hole 10 in the side rail. The
handle 26 also includes a locking lug 34 for locking with
the interior of the side rail. As seen in Figure 2, this
locking lug, when rotated to the storage position of Figure
4, is partially captured within one of the securing slots
10. This provides positive retainment of the handle within
the storage position. This is particularly appropriate for
storage of panels where the clamp is retained in the
storage position and is not prone to damage. It can be
appreciated that it is within the perimeter frame 6 of the
wall panel form and is retained in that position due to
engagement of the locking lug 34 with one of the securing
slots 10.
If the clamp 20 becomes damaged or requires
replacement, locking pin 40 is removed and the handle can
then be rotated to allow the camming faces 24 and 25 to
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WH-9574cA 2179084
align with the keyhole 18 in the bracket 16. A new clamp
can then be inserted.
It can be appreciated that the concrete wallform
panels 4 will preferably have a series of clamps along each
side rail for engaging adjacent wallform panels. These
panels will also have captured clamps for providing
additional securement.
The clamping members can be located on the side
rails according to a predetermined arrangement to reduce
the possibility of two clamping members being positioned
opposite one another when wall panels are brought into
abutment.
It can also be appreciated from the above
description that the clamp members need not be all captured
and it is certainly possible to have separate clamps which
are merely inserted into desired aligned securing slots
during assembly of the panels.
Although various preferred embodiments of the
present invention have been described herein in detail, it
will be appreciated by those skilled in the art, that
variations may be made thereto without departing from the
spirit of the invention or the scope of the appended
claims.
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Representative Drawing