[0001] The present invention relates to formwork systems and, more particularly, to a formwork
panel. More specifically, the present invention relates to innovations in panels which
are especially useful in the field of light or 'hand-portable' panels, that is, formwork
panels that are designed to be moved manually, without the intervention of machinery,
such as cranes.
[0002] Said panels are characterised with respect to non-hand-portable panels in being lighter.
However, it should be borne in mind that the reduction in weight of the panel must
not be achieved at the cost of the necessary rigidity of the panel and, in general,
of the entire formwork system.
[0003] Formwork panels usually comprise:
- a moulding element which comprises the moulding surface; said element is usually a
panel or set of panels made of timber,
- a series of structural reinforcement ribs (usually made with a rectangular or open
U- or C-shaped profile), and
- a frame which surrounds the formwork element at least along two parallel sides.
[0004] In ultra-light panels, and with the object of reducing weight, it is usual for the
frame to be formed by a hollow profile, usually made of sheet metal. The profile has
a projection or fin and an adjacent surface for receiving the formwork element with
the formwork surface. In addition, the profile has a face with two zones to which
the rib is connected by welding and a recess between said zones, the object of which
is to receive panel-connection means. In ultra-light panels, it is usual for the wall
of said face to come in contact with the wall of the opposite face of the profile
in the recess zone. The edge of the ribs is flush with that of the profile less the
thickness of the moulding element, or in other words, flush with the edge of said
face with the zone or zones to which the rib and the recess are connected. Thus, rib
and frame are level, and neither projects relative to the other.
[0005] An object of the present invention is to disclose means that allow a reduction in
the weight of these types of systems and panels without a reduction in strength, obtaining
an excellent compromise between strength and weight.
[0006] More particularly, the present invention discloses a formwork panel which comprises:
- a moulding element which comprises the moulding surface; said element is usually a
panel or set of panels made of timber
- a series of structural reinforcement ribs, and
- a frame which surrounds the formwork element at least along two parallel sides
the frame comprising a hollow profile which comprises a zone for receiving the moulding
element and a face which comprises two rib-connection zones and a support zone for
panel-connection means,
in which
the support zone projects relative to at least one of the rib-connection zones.
[0007] Preferably, the two rib-connection zones are not aligned. More preferably, the support
zone is a straight length of wall which forms an oblique angle with the rib-connection
zones.
[0008] According to another aspect of the present invention, the edge of the rib may be
lower than that of the face of the profile which comprises said connection and support
zones, so that the profile projects relative to the rib.
[0009] According to the present invention, the ribs may be connected to the profile by welding
and the profile may be made of sheet metal.
[0010] More preferably, the support zone is neither parallel nor perpendicular to any of
the other faces of the profile.
[0011] Preferably, both connection zones are parallel, with the outermost connection zone
positioned closer to the centre of the panel than the innermost connection zone.
[0012] The present invention also comprises a formwork system which comprises panels according
to the present invention. Advantageously, the formwork system comprises at least one
panel in which the rib is set back relative to the profile and one panel in which
the rib is set back relative to the profile. Preferably, the system will also comprise
at least one clamp for connecting adjacent panels in which the shape of the clamp
matches that of the support zone of the panels.
[0013] According to the present invention, the support zone is formed as a projection and
not as a recess. This signifies a reduction in weight for the following reasons:
- It allows the ribs to be cut to match the shape of the profile. As the support zone
projects, the amount of material of the ribs is reduced.
- With regard to the profile with a recess, the profile gains rigidity without an increase
in the surface area of sheet metal required to produce said profile. Because said
profile has greater rigidity, the thickness thereof can be reduced and, hence, the
weight thereof.
[0014] Because the support zone is formed as a face which is neither parallel nor perpendicular
to any of the other faces of the profile, errors in placing the connection clamps
are avoided.
[0015] The fact that the outermost connection zone is positioned closer to the centre of
the panel than the innermost connection zone helps ensure the viability of the ribs
which are set back relative to the profile.
[0016] Moreover, the configuration of the present invention helps ensure that the outermost
support zone is larger than the innermost, further enhancing the possibility of using
ribs that are set back relative to the profile.
[0017] For a better understanding, the accompanying drawings show an embodiment of the present
invention given as an explanatory but non-limiting example.
Fig. 1 is a transverse cross section along a horizontal plane of an ultra-light formwork
panel according to the prior art, in which can be seen the moulding element, the profile
that forms the frame and the rib.
Fig. 2 is a view in transverse cross section of an embodiment of a profile for a formwork
panel according to the present invention.
Fig. 3 is a transverse cross section along a horizontal plane of an embodiment of
an ultra-light formwork panel according to the invention, in which can be seen the
moulding element, the profile of Fig. 2 and a rib.
Fig. 4 is a variant of the panel of Fig. 3.
Fig. 5 shows two panels according to the present invention connected by a clamp belonging
to a formwork system according to the present invention.
Fig. 6 is a perspective view of a clamp according to the present invention.
Fig. 7 is a view in cross section along a horizontal plane of a formwork system according
to the present invention, with sets of parallel panels which leave a moulding space
internally.
Fig. 8 is a variant of the embodiment of Fig. 7.
Fig. 9 is another variant of the embodiment of Fig. 7.
Fig. 10 is yet another variant of the embodiment of Fig.7.
Fig. 11 is a view in elevation of an assembly of a formwork system according to the
present invention, in which four panels define the moulding space of a column.
Fig. 12 is a plan view from above which corresponds to the plane XII-XII of Fig. 11.
Fig. 13 is a detail of Fig. 12 which shows the support of the head of a threaded connection
bolt in the connection zone of the profile of the frame of the panel.
[0018] Fig. 1 shows an ultra-light formwork panel according to the prior art. More specifically,
said figure shows a transverse cross section of one of the side edges of a panel,
in order to show clearly the elements that make up said panel.
[0019] The panel is made up of a moulding element -11- which comprises a moulding surface
-111-. The moulding surface -111- has the function of limiting the space occupied
by the concrete, while possibly remaining in contact therewith. On the rear portion,
that is to say, on the portion opposite the moulding portion a series of ribs -12-
runs over the panel from side to side. The panel also has a frame which runs round
said panel at the perimeter thereof. The frame is formed by a hollow profile -13-,
made of folded sheet metal. The profile has a seat formed by the moulding element
-11- which is formed by a projection -131- or fin which protects the side of the moulding
element and a seat surface -132- formed by an adjacent wall of the profile. Immediately
adjacent to the seat is a first zone -133- for connection by welding to the rib. Following
the first connection zone -133- is a support zone -134- for connection means which
is formed as a recess in the profile. The most set back wall of the support zone,
in this case, comes in contact with the opposite wall of the profile -137-. An edge
wall -136- is situated between the two opposite walls which defines the point of the
profile -13- that projects most relative to the moulding element -11-. The rib -12-
is flush with the profile at the height of said edgewise wall -136-. The opposite
wall -137- in turn has a slight recess to facilitate handling the panel.
[0020] Fig. 2 shows a profile -13- which corresponds to a formwork panel according to the
present invention. Elements that are the same or similar to those shown in the previous
figure have been identified with identical reference numerals and will therefore not
be explained in detail. Compared with the profile -13- of Fig. 1, it can be seen that
one difference is that the support zone -134- is not formed as a recess in the profile
-13-, but rather is a zone which projects relative to the first connection zone -133-.
In particular, the support zone -134- is formed as an oblique wall zone relative to
the first and second support zones -133-, -135-. More particularly, it will be seen
that the support zone is neither parallel nor perpendicular to any of the walls -131-,
-132-, -133-, -135-, -136-, -137- of the profile -13-. In this profile it can be seen
that the first support zone -133- and the second support zone -135- are not aligned,
although, in this case, said zones are parallel. Furthermore, it can be seen that
in this case, the length (and consequently the area) of the second connection zone
-135- is greater than that of the first connection zone -133-. This facilitates the
use of ribs that are not flush with the profile. This effect is also enhanced by the
fact that the second connection zone -135-, which is the outermost connection zone,
is positioned closer to the centre of the panel than the first connection zone -133-.
This makes it more difficult for the rib to come out of position and consequently
limits the connection requirements, for example, by welding. This will allow, if required,
the rib to be connected effectively only to one of said connection zones, if desired.
[0021] As can be seen, unlike in the prior art, the present invention may use stepped profiles.
In particular, there may be no depressed zones in the contact face with the rib.
[0022] A comparison of the profiles -13- of Fig. 1 and 2 shows that the production of the
profile -13- in the example shown in Fig. 2 requires the same amount of sheet metal
as that in Fig. 1, but has greater rigidity relative to the forces to which said profile
is exposed inside the formwork panel. This means that, if required, the profile of
Fig. 2 can be produced, for the same strength, with a smaller thickness, producing
a panel with less weight. In addition, and given that the width of the profile is
greater, smaller ribs are required with the profile of Fig. 2, resulting in an additional
loss of weight.
[0023] Fig. 3 and 4 show two embodiments of a formwork panel -1- according to the present
invention. Elements that are the same or similar to those shown in the previous figures
have been identified with identical reference numerals and will therefore not be described
in detail. The panels -1- of Fig. 3 and 4 have a similar outline to that described
in Fig. 2, and have a frame that uses a profile -13-, with the consequent saving of
material in profile -13- and rib -12- compared to the case in Fig. 1. In Fig. 4, both
the profile and the rib are flush, as can be seen by comparing the positions of the
end wall -136- of the profile -13- and the free end -126- of the rib. In Fig. 3, on
the contrary, it can be seen that the rib -12- has smaller dimensions and the free
end -126- thereof is set back, or closer to the moulding element -11- than the end
wall -136- of the profile -13- which forms the frame, with the consequent saving in
weight. This configuration is particularly suitable for frames with small dimensions,
that is, with a smaller rib length, or distance between supports, or with lower functional
requirements, that is, designed for a lower pressure of formed concrete, or in panels
with a small distance between ribs. This allows the weight of the panels to be optimised
still further, by adjusting said panels to the dimensions and/or mechanical requirements
thereof.
[0024] In both cases, the ribs are cut according to a profile that matches the profile that
forms the frame. The shape of the profile of the panel according to the present invention
permits welding even though the edge of the rib is smaller than the usual edge and/or,
in particular, than that of the frame.
[0025] Fig. 5 shows an embodiment of a portion of a formwork system according to the present
invention, in which two formwork panels -1-, -1'- positioned next to each other are
connected by a clamp -2-. The clamp -2- is adapted to the shape of the support zone
-134- of the profile -13-, each of the arms -21-, -21'- of the clamp having a matching
support surface -211-, -211'-. Fig. 6 shows an embodiment of the clamp in detail.
[0026] Fig. 7 to 10 show other embodiments of formwork systems according to the present
invention. In particular, said figures show configurations in which different adjacent
panels, with the profiles thereof -13-, -13'- in contact and others parallel thereto,
form the formwork space of, for example, a wall. Accordingly, both sides of the formwork
are connected, as is known, by tie bars -4- and the corresponding nuts -5- which act
on distribution plates -3-. In the case of systems according to the present invention,
the distribution plates -3- provide for the existence of panels with different types
of rib -12-, -12'-.
[0027] In Fig. 7 the distribution plate -3- must act on two panels that have ribs -12-,
-12'- that are set back relative to the profiles -13-, -13'- at different heights.
Accordingly, two projections -31-, -32- are arranged on the distribution plate -3-,
the length of each of the projections corresponding to the difference between the
edge of the profile -13-, -13'- of one type of panel and the edge of the profile -12-,
-12'- of said type of profile. This allows the same distribution plate to be used
in the configurations of Fig. 7 and 8. In the example shown, the projections -31-
and -32- are arranged on opposite faces of the distribution plate -3-. Fig. 9 and
10 show two more configurations obtained with a distribution plate -3- which varies
with respect to that shown in Fig. 7 and 8 in that said plate has only one projection
-32'- at one end, and the other end -31'- has no projection. As can be seen in Fig.
9, the length of the projection -32'- coincides with the difference between the edges
of rib and profile. In Fig. 10, the absence of an edge at one of the ends is used
for configurations in which the rib -12"- and the profile -13"- have the same edge
and are therefore flush.
[0028] It has been possible in the previous figures to see how the provision of projections
on the distribution plate allows a single type of distribution plate to be used for
two different panel types.
[0029] Fig. 11 to 13 shown another example of a configuration of a system according to the
present invention, in which a formwork for square or rectangular columns is produced.
Elements that are the same or similar to those shown in the previous figures have
been designated with identical reference numerals and will therefore not be described
in detail. For this type of connection, a partly threaded bar -3- is used with a head
-61- shaped as an asymmetrical T which has a projection -611- with a shape that matches
the support zone -134- of the profile -13- of the panels, so as to ensure good contact
between said surfaces.
[0030] Although the invention has been presented and described with reference to embodiments
thereof, it will be understood that said embodiments do not limit the invention, and
therefore many structural or other details which may be evident to persons skilled
in the art after interpreting the subject matter disclosed in the present description,
claims and drawings, may vary. Thus, all variants and equivalents will be included
within the scope of the present invention if said variants and equivalents may be
considered to fall within the most extensive scope of the following claims.
1. Formwork panel which comprises:
- a moulding element which comprises a moulding surface;
- a series of structural reinforcement ribs, and
- a frame which surrounds the formwork element at least along two parallel sides
the frame comprising a hollow profile which comprises a zone for receiving the moulding
element and a face which comprises two rib-connection zones and a support zone for
panel-connection means,
in which
the support zone projects relative to at least one of the rib-connection zones.
2. Panel, according to the preceding claim, in which the rib-connection zones are not
aligned.
3. Panel, according to the preceding claim, in which both connection zones are parallel,
with the outermost connection zone positioned closer to the centre of the panel than
the innermost connection zone.
4. Panel, according to any one of the preceding claims, in which the support zone is
a straight length of wall which forms an oblique angle with the rib-connection zones.
5. Panel, according to the preceding claim, in which the support zone is neither parallel
nor perpendicular to any of the other faces of the profile.
6. Panel, according to any one of the preceding claims, in which the edge of the rib
is lower than that of the face of the profile which comprises said connection and
support zones, so that the profile projects relative to the rib.
7. Panel, according to any one of claims 1 to 5, in which the edge of the rib is such
that rib and profile are flush, and do not project relative to one another.
8. Panel, according to any one of the preceding claims, in which the profile is made
of sheet metal.
9. Panel, according to any one of the preceding claims, in which the ribs are connected
to the profile by welding.
10. Formwork system which comprises panels according to any one of the preceding claims.
11. System, according to the preceding claim which comprises a panel according to claim
6 and a panel according to claim 7.
12. System, according to either claim 10 or claim 11, which comprises at least one clamp
for connecting adjacent panels in which the shape of the clamp matches that of the
support zone of the panels.