Note: Descriptions are shown in the official language in which they were submitted.
~;~764~
Title: A Floor Structure
Technical Field
The invention relates to a floor structure comprising a
flooring situated on a first lower and a second upper
layer of parallel and mutually spaced joists, whereby one
layer extends substantially perpendicular to the joists
of the other layer, and whereby the first layer of joists
is situated on chocking means arranged at regular inter-
vals, said first layer furthermore being provided with a
slot immediately above the chocking means.
Back~round Art
It is known to manufacture floor structures with a flooring
of for instance parquet and situated on two layers of
parallel joists, whereby the joists of one layer extend
perpendicular to the joists of the second layer, and where-
by the two layers of joists abut one another directly and
are situated on chocking means arranged at regular inter-
vals. The joists abutting the chocking means directly are
provided with a sawn vertical cut extendin~ preferably
into half thickness. Such a flooring does not, however,
provide a satisfactory flexibility over a surface, i.e.
the so-called surface flexibility, which is sufficient
for being suitable as a sports floor. The latter is especi-
ally due to the fact that the floor structure does not
disclose a sufficient flexibility on the sites where the
joists of the two layers are intersecting. The cuts in
the lower layer of joists damp the transmission of vertical
oscillations in the flooring during the use.
Disclosure of ~nvention
The new and characteristic features of the floor structure
according to the invention are:
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that resilient spring elements separating the two layers
are situated at the intersections between the two layers
of joists.
In this manner a floor structure is obtained in a simple
and inexpensive manner which over a surface discloses a
flexibility everywhere allowing the floor to be used as
a sports floor. At the same time it is possible to manufac-
ture the flooring of solid wood and thereby the flooring
is particularly resistant to the loads exerted ther~on.
According to the invention it is particularly preferred
that the resilient spring elements are substantially solid
and made of rubber or plastics.
Furthermore the second layer of joists may according to
the invention be provided with a slot immediately above
the spring elements, and the mutual distance and cross-
sectional dimensions of the joists may be such that the
following formula is met:
LlElIl = K L2E2I2~
where K is a structure constant varying between 0.1-1.5,
but preferably between 0.55-0.65, and E is the elasticity
module, L the distance between the joists, and I the moment
of inertia, and whereby the symbol l refers to the upper
layer of joists, and the symbol 2 to the lower layer of
joists. In this manner the flooring meets the requirements
presented especially in some countries to the surface
flexibility of sports floors. These requirements correspond
to the requirements applying in the Federal Republic of
Western Germany in the form of DIN 18032 part II.
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Specifically, the present invention provides a floor
structure which comprises a flooring which is situated on top
of a first lower and a second upper layer of parallel,
interspaced joists whereby the joists of one layer extend
substantially perpendicular to the joists of the other layer
and whereby the first layer of joists is situated on top of
chocking means which are arranged at regular intervals. I'he
first layer of joists is also provided with a slot immediately
above the chocking means. ~he floor structure being
characterized in that resilient spring elements which separate
the two layers of joists are situated at the intersections of
the two layers of joists.
rn/ss
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Brief Description of Drawings
The invention will be described below with reference to
the accompanying drawing, in which
Fig. 1 is a vertical, longitudinal, sectional view through
a floor structure according to the invention,
Fig. 2 is a top view of the structure of Fig. 1, whereby
the flooring has been removed for the sake of clarity, and
Fig. 3 is a vertical, transverse, sectional view through
the floor structure of Figs. 1 and 2.
Best Mode for CarrYinq Out the Invention
The floor structure of Figs. 1, 2, and 3 comprises rows
of chocking means 1 situated on a foundation 2. ~hese
chocking means may in a manner known per se comprise one
or more wood blocks 3 and 4 situated atop one another,
wedging means 5 or another type of levelling means being
situated on top of said chocks. A first layer of parallel
joists 6 is situated on top of these chocking means 1,
said joists being situated at the same mutual distance
and supported by the chocking means at sites also situated
at the same mutual distance. Immediately above the chocking
means the joists 6 are provided with a vertical cut sawn
down and extending from the top and downwards to half the
thickness of the joists 6. These cuts have been indicated
by the reference numeral 7. A second layer of joists 8 is
situated on top of the first layer of joists 6, said second
layer of joists also extending in parallel at the same
mutual distance but also extending perpendicular to the
joists 6 of the first layer. Small solid, resilient spring
elements 9 are situated everywhere between the two layers
of joists 6 and 8, and immediately above these spring
elements 9 the joists 8 disclose a vertical cut 12 sawn
down and extending at a depth of 2/3 of the thickness of
the joists 8.
J.~,~
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A flooring 10 of solid parquet is situated directly on
the second layer of joists 8.
The joists 6 and 8 of the two layers of joists must be
situated at such a mutual distance and be dimensioned in
such a manner that the dynamic resilience of the completed
floor does not separate more than 15% from one another at
the softest and the most rigid measuring site on the floor
surface. In this manner the floor structure meets the
requirements presented in the Federal Republic of Western
Germany in the form of DIN 18032 part II and corresponding
to the requirements presented in several other countries
in order to allow the floor ~tructure to be used as a
sports floor. These requirements are met pro~ided
LlElIl = K L2E2I2~
where K is a structure constant varying between 0.1-1.5,
but preferably between 0.55-0.65, E is the elasticity
module, L is the distance between the joists, and I .s
the moment of inertia. The symbols 1 and 2 refer to the
second layer of joists 8 and the first layer of joists 6,
respectively.
By the preferred floor structure the joists 8 of the second
layer of joists disclose the cross-sectional dimension 70
x 35 mm and the joists 6 of the first layer of joists the
cross-sectional dimension 45 x 45 mm, whereas the spring
element discloses the dimension 50 x 50 x 24 mm. The chock-
ing means are made of joists of a width of 50 mm and as
to height they have been arbitrarily chosen in such a
manner that together with the wedging means 5 they allow
a horizontal levelling of the flooring of the floor struc-
ture.
As indicated in Figs. 1 and 2, an isolation 11 of a suit-
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able type is situated on top of a vapor blocking layereverywhere between the chocking means.
Concerning the resilient spring elements, the dimension
and shape thereof can vary according to desire as the
abutment surface is preferably at least 50 x 50 mm and
the thickness is preferably at least 17 mm. According to
desire the elements may be profiled, i.e. they may for
instance comprise grooves extending longitudinally. In
order to facilitate the putting down procedure the spring
lo element~ may therefore be provided with a suita~le profil-
ing. The spring elements may be made of many different
materials such as caoutchouc, neoprene rubber, nitrile
rubber, polyvinyl chloride, ethylvinyl alcohol, polyure-
thane, polyacryl, polypropene, polyethene, polystyrene or
other similar materials or mixtures thereof. By the pre-
ferred embodiment the spring elements are made of a rub-
ber-like material sold under the Trade Mark "Regupol".
The flooring is preferably made of solid, 22 mm thick
press-dried beechwood parquet. Other floorings may, howev-
er, also be used such as for instance 18-20 mm thick ply-
wood, on which needle felt or a thin layer of plywood or
another type of flooring material is situated.
The spring elements may be secured on the adjacent joists
in any suitable manner such as by gluing or by means of
nails.
If all the parts of the floor structure are made of wood,
these parts should during the putting down of the floor
disclose a moisture per cent as follows: The joists 8: 12~,
the joists 6: 12%, the wood chocks 3 and 4: 12%, and the
parquet: ~%. In order to guarantee these moisture per
cents the materials should be packed in a dampproof mate-
rial until the time of application, and the moisture con-
tent should be maintained during the putting down of the
floor. Concerning the distances the various parts of the
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preferred embodiment are interspaced as follows when meas-
ured in the horizontal direction: The joists 6 of the
first layer of joists: 41.1 cm, the joists 8 of the second
layer of joists: 33.6 cm, and the chocking means 1: 67.3
cm measured in the longitudinal direction of the joists 6.
