Note: Descriptions are shown in the official language in which they were submitted.
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Building element and method for manufacturing a building
element
The present invention relates to a method of manufacturing a
building element, and also to a building element suitable for
manufacture a.n accordance with the method. The invention also
relates to a building constructed from said building elements.
The building element is preferably a log, particularly a timber
log, which is provided with jointing recesses or apertures by
means of which such building elements can be joined together.
In the older construction of log cabins, the logs were hammered-
in manually so as to obtain tight corner joints. Because of the
varying dimensions of the logs, it is necessary to adapt each log
individually to match adjacent logs. This task is very time-
consuming and requires a great deal of skill and cannot therefore
be accomplished by the general public, but must be assigned to a
few specialists in the art.
"Log cabins" are today manufactured industrially in accordance
with modern methods. These prefabricated log cabins, or timber
houses, are bought in the form of a finished construction set
which leaves the purchaser very few possibilities of influencing
the general layout of the building and its general appearance,
etc.
The actual character of a log cabin or timber house, by which is
meant a cabin built of logs that are "dove-tailed" at the
corners, will disappear to a very large extent as a result of
'30 working the logs industrially in different ways. Accordingly, the
object of the present invention is to provide building elements
in the form of timber logs which are suited for use in the
construction of log cabins piece-wise. The logs can be joined
together in different ways, so as to enable the builder to
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influence the general layout of the building himself/herself. The
logs shall also be inexpensive and the jointing recesses prepared
so as to enable the logs to be joined easily but nevertheless
tightly while retaining a log cabin character. The resultant
building shall also have the character of a log cabin built from
round timber. Finally, it shall be possible to produce the
building elements industrially in a rational fashion.
This object is achieved in accordance with the present invention
by virtue of a method in which logs, preferably timber logs, are
cut into modules, which may have different total lengths, and by
then centering each module in relation to a longitudinal,
selectable centering line chosen so that each line will form a
longitudinally extending centre line of the joint centre pin in
the final building element.
The object of the invention is also achieved with a building
element which is particularly suitable for use in the aforesaid
construction method, wherein for the purpose of forming a joint
centre pin in which said pin is centred around a selected
longitudinally centering line of the log, said log is provided
around its periphery with four jointing recesses which are
mutually offset through an angle of 90° along the periphery,
wherein the log has a predetermined thickness D which a.s obtained
by working two mutually opposing sides of the log in its longitu-
dinal direction, thereby forming two shape-bound abutment sides
for abutment with corresponding sides of the nearest adjacent
logs.
Finally, the invention also pertains to a building constructed of '
said building elements.
Other characteristic features and embodiments of the invention
will be evident from the depending Claims.
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The invention provides several advantages in addition to achiev-
ing the aforesaid obj ect . For instance, the logs may have varying
wood dimensions, therewith placing less stringent demands on the
choice of wood. The log jointing recesses are mutually identical
on all logs, therewith enhancing flexibility. For instance, logs
according to the preferred embodiment can be turned upside-down.
The inventive building elements also provide tight corner joints,
although sealing strips may be placed over the joints if so
desired. The invention also affords the advantage that, if so
desired, both -the outside and the inside of the resultant
building may be given the appearance of timber logs, so that the
cabin, or house, will have all the characteristics of a "log
cabin".
The invention will now be described in more detail with reference
to the accompanying drawings, in which
Fig_ 1 is a schematic illustration of a building element accord
ing to a first embodiment of the invention, in the form of a log
provided with two jointing recesses;
Fig. 2 is a schematic illustration of a second embodiment of a
building element in the form of a log having three jointing
recesses;
Fig. 3 is a view from above of two joint-forming logs cross-laid
at an angle A;
Fig. 4 illustrates two cross-laid logs corresponding to Fig. 3
'30 but according to another embodiment in which angle A is equal to
90°;
Fig. 5 is a side view of a log according to Fig. 4 and illus-
trates the joint-forming recesses more clearly;
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Fig. 6 illustrates the log in Fig. 5 from above; ,
Fig. 7 is a sectional view of the log shown in Fig. 5 taken ,
through the line VII-VII; and
Fig. 8 is a sectional view of another log embodiment in which the
abutment surfaces have a drop nose configuration.
In practicing the inventive method, logs are cut into modules 1,
IO 4, 10, 40, which may have different total lengths. Each module is
then centred along a predetermined, longitudinally extending
centering line a, b chosen so that said line will become the
geometrical, longitudinally extending centre line of the centre
pins 13, 15 of the jointing recesses 2, 3, 5, 6, 7, 12, 14 of the
final building element subsequent to working the sides of the log
to provide these jointing recesses. Subsequent to centering each
module, two longitudinally extending sides 16, 18, 46, 48 of said
module are worked to provide shape-bound abutment surfaces, e.g.
a drop-nose ? shape (Fig. 8) for instance, either by double sash
sawing or in some other suitable way. The module, or log,
therewith obtains a thickness D (i.e. a height in a horizontal
position) between the worked sides that is predetermined by
virtue of the fact that the height or thickness of the centre pin
13, 15 for the future joint is determined as D/2. The jointing
recesses 20, 22, 30, 32 are then produced so as to form a centre
pin 13, 15 for each joint. The jointing recesses may optionally
be provided prior to working the sides of respective modules.
Fig. 1 illustrates a first embodiment of an inventive building
element in the form of a timber log 1 which has been cut to '
provide a module that includes two jointing recesses 2, 3 at
respective positions along the module, normally in the vicinity '
of its ends. The module is cut to a length such that the distance
between the two jointing recesses has a predetermined length 1.
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1 is equal to L in the illustrated case. Fig. 2 illustrates a
second embodiment of an inventive building element in the form of
a module 4 that has been cut so as to include three jointing
recesses 5, 6, 7.
5
The inventive building element will be described hereinafter
mainly with reference to Figs. 5, 6 and 7 which illustrate the
special case from Fig. 4 in which A=90°, although the following
description is also valid in respective of other values of the
angle A, as shown in Fig. 3, for instance. The described building
element may be any one of the modules illustrated in Fig. 1 or
Fig. 2, or may be some other module.
Fig. 5 is a side view of a module 10 provided with jointing
recesses 12, 14 close to respective ends of the module. The
module has been double sash sawn on two mutually opposing sides
so as to provide flat abutment surfaces 16, 18; see also Fig. 6.
When the log modules are j oined together horizontally, one on the
other, the respective module abutment surfaces will be in mutual
abutment. Because the modules are double sash sawn, each module
will have a constant vertical height D. This height may be varied
depending on the thickness of the modules, or logs, available,
although it is the intention that a large number of modules will
have mutually the same dimensions so that the purchaser is able
to calculate how many modules are required to build a wall of
given height,.and also to enable the walls to be constructed. The
diameter D constitutes a so-called ascending height. However, the
width of respective modules and therewith the sides of the
modules does not change as the modules are placed one on the
'30 other, and the modules thus retain their timber log appearance.
The jointing recesses are provided in the module evenly from four
directions and are offset in relation to one another by 90°
around the periphery of the module. The recesses 20, 22 provided
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in the flat sides of the module have a depth Sd which is equal to
D/4 in the double sash sawn embodiment. Seen in the cross-
direction of the module, these recesses have two cut surfaces 24,
26 which extend from a flat surface 28 parallel with the sawn
sides of the module. The angle E defined by the cut surfaces 24,
26 and the flat surface 28 may vary between 90 ° and 160 ° . The
angle E is preferably about 135 ° . When the angle E is greater
than 90°, the cut surfaces 24, 26 will slope so that the recess
20, 22 narrows towards the flat surface 28. The recesses 30, 32
which are provided in the original sides of the module, i.e. the
unsawn sides, have two cut surfaces 34, 36 which extend in the
transverse direction of the module. The cut surface 34 defines an
angle C with the selected centering line b in the long direction
of the module, while the cut surface 36 defines an angle B with
the same centering line. The angle B is equal to 90°+A/2, and the
angle C is equal to 180°-A/2; see also Fig. 4 and Fig. 3 in this
regard. The module has a further two cut surfaces 38, 39 on
respective sides thereof between the cut surfaces 34 and 36 and
on both sides of an imaginary plane extending through the module
centering line B parallel with the sawn sides. As evident from
Fig. 7, these cut surfaces define an angle F with an imaginary
plane extending through the centre line of the centre pin
parallel with the flat surface 28. The cut surfaces 38, 39 slope
for coaction with the cut surfaces 24 and 26, meaning that the
angle F is equal to the angle E. The joint centre pin 13 is thus
delimited by'two flat surfaces 28 which are horizontal when the
module lies horizontally, and the cut surfaces 38, 39 on the
unsawn sides of the module. The planar surfaces 28 on the
respective upper side and underside of the centre pin 13 have the
form of an equal sided parallelogram. In the case of the embodi- '
ment illustrated in Figs. 4, 5 and 6, the joint centre pin 13 is
square whereas in the Fig. 3 embodiment, it has a rhomboidal
shape. The shape of the centre pin depends on the angle A at
which the modules shall cross one another. The height of the
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joint centre pin is D/2. As before mentioned, the modules in the
embodiment illustrated in Figs. 4, 5 and 6 are intended to cross
one another at an angle A=90°. B will then be 135° and C will be
135°. It is thought that this will be the angle that is most
used, although other angles are feasible.
The length of the sides of the equal-sided parallelogram forming
the joint centre pin 13 may vary in accordance with the original
measurements of the module or log and also with regard to the
angle A. According to one preferred embodiment, the sides have
the length D/2. However, the height or thickness of the centre
pin will be determined completely by the predetermined ascending
height, i.e. the dimension D, and will always be D/2. Alterna
tively, it can be said that the ascending height is determined by
the chosen sides of the centre pin.
As will be evident from Fig. 6 and also from the broken line
illustrations in Fig. 5, the modules may be provided with a
number of holes 15 that join together the sawn sides of the
module. These holes are situated in the same positions on all
modules, so as to lie in register with one another when joining
the modules together. These holes are able to receive module
fastening devices that extend through several modules. The
fastener devices used will preferably be screw fasteners.
As will also be evident from Fig. 6, the sawn sides of the module
may be provided with longitudinally extending grooves 54 capable
of receiving a loose tongue when joining the modules together.
Alternatively, one of the sawn sides may be provided with a
~30 groove and the other of said sides provided with a tongue so as
to obtain mutually coacting tongues and grooves when joining
together the modules.
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In the aforedescribed preferred embodiment, the modules have two
double sash sawn sides. However, the worked sides of the module
may alternatively have another form such as the drop-nose form ,
shown in Fig. 8. In this case, the sloping abutment surfaces of
the worked sides of the module have been referenced 46, 48, while
details that find correspondence in the earlier described
elements have been identified with the same reference signs. The
above-described configuration of the centre pin and the jointing
recesses can also be applied in this embodiment.
As before mentioned, the building element of the Fig. 1 embodi-
ment is a timber log 1 that is cut to provide a module that has
two jointing recesses 2, 3 at respective ends of the module. The
log is cut so that the distance between the two jointing recesses
will have a given predetermined length 1. This length 1 is
conveniently a whole number multiple of a predetermined measure-
ment L. In the illustrated case, 1 = L. The module illustrated in
Fig. 2 is a log 4 which has been cut to a length such as to
include three jointing recesses 5, 6, 7. The jointing recesses
may be separated equidistantly by the distance 1, which also in
this case is a whole number multiple of a predetermined measure-
ment L . The log may alternatively have only two j ointing recesses
which would then be separated by a distance corresponding to 2L,
i.e. the jointing recess 6 would have been omitted. An inventive
module building element may also include more jointing recesses
than three, such as four or five recesses for instance, in which
case the log or module will be correspondingly longer. This
enables the length of the modules, or logs, and the number of
jointing recesses to be varied constantly. The only condition is
that the distance between two jointing recesses will always be a '
whole number multiple of a predetermined measurement L. The
measurement L is determined from a starting point with regard to
what is desired by the purchaser and also with respect to
available log lengths. The result is a set of building elements
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based on a module conception, where the builder has a great deal
of freedom in combining different modules according to her/his
wishes. A suitable measurement of L is thought to be 2.5-5
meters, preferably about 1 meter.
A building is constructed from the building element, by placing
the building elements cross-wise on top of each other and
therewith alternating in directions at an angle A, said angle
being predetermined by the configuration of the jointing recess-
es, and laying said elements one on the other until a desired
wall height is reached. Inner walls can be formed from building
elements that have a jointing recess located between the two
jointing recesses at respective ends of the building element.
This enables the builder to determine the general layout of the
building himself to a large extent. The building is then complet-
ed by installing an appropriate ceiling, door openings and window
openings, and a floor.
The invention thus enables a log cabin to be constructed readily
without requiring the skill of an expert in this field, and also
enables the purchaser to decide the general layout himself.
It will be understood that the invention is not restricted to
what has been described and illustrated and that modifications
can be made within the scope of the following Claims.
