[0001] The present invention relates to a device for the manufacture of laminated wood bent
elements, according to the preamble of claim 1. Such a device is known from the document
EP1125700A1.
[0002] Wooden arches and bent structural rafters are increasingly used as bearing elements
in building structures. The strength of this kind of elements manufactured from laminated
wood is many times greater than the parameters of elements which are the same in dimensions
but manufactured and bent from solid wood. In structural applications laminated wood
makes it possible to make large span covers and is used when high strength of material
is needed. Laminated wood is made by gluing together layers of wood with a thickness
typically from 5 mm to 50 mm. The thickness of layers is selected depending on the
application and the required bending radius of the final profile. Laminated wood during
gluing can be formed in curvatures which are difficult to obtain from solid wood.
Individual layers in the form of wooden slats are interlaid with layers of adhesive,
and then pressed. During the pressing process, before the adhesive hardens, they are
bent and in that bent shape are maintained until the layers connecting the surfaces
of individual slats are hardened. A number of solutions of devices used for this purpose
is known.
[0003] A known solution is disclosed in the Polish patent specification of application number
P.400102. It discloses a device for pressing resilient material, particularly wood material,
comprising a frame with an openwork table and a holding beam and containing an upper
load plane in the form of a casing. The device according to this known solution comprises
a bottom unit and an upper unit and rolls for tapes on both of the units. The bottom
unit contains a frame with an openwork table and a moving holding beam and a moving
pins assembly and a guide assembly of binding material. The upper unit contains a
multi-part moving casing. A method of pressing resilient material, particularly wood
material is accomplished by placing material on the openwork table, holding it from
the top by the casing and binding. Small bundles of material are placed on the openwork
table, and then pushed using the holding beam to the vertically arranged moving casing.
From the bottom and from the top a wire or a binding tape is spread from the rolls
on the binding material. The material by being put between the binding material is
then pressed by the casing turning through an angle of 90°.
[0004] The known solution according to document
US 333615 discloses a device for the manufacture of laminated wood bent elements comprising
a working board with fixing holes and a clamps assembly attached to the working board.
Each clamp comprises a bottom beam to which a retaining plate with the screw is fixed,
perpendicular to the bottom beam and a clamping plate perpendicular to the bottom
beam are attached. The clamping plate is slidably attached in the clamp by means of
a screw. Another known solution is disclosed in the specification of the Chinese utility
model application number
CN203738952. The solution according to this utility model is used to bend and cold form laminated
wood. According to this utility model, two hydraulic cylinders are respectively arranged
at two ends of a worktable longitudinally. One of the hydraulic cylinders is connected
with a pressing die. The other hydraulic cylinder is connected with a push plate.
An arc-shaped recess is formed in an end surface, which is opposite to the push plate.
Sliding ways are arranged on the worktable for moving the pressing die and the push
plate. The push plate and the pressing die with the arc-shaped recess can move along
the sliding ways. The worktable is provided with supports and an upper crane runway
with an electric hoist. The bending forming cold press according to this utility model
is useful in the manufacture of bent and cold formed laminated and at the same time
shaped wooden elements in the form of slats.
[0005] Another known solution is disclosed in american patent specification number
US 4,711,281. According to this known solution, a curved wood bending machine for bending wooden
members has a support frame with a generally semicircular planar top member on which
a plurality of guide rails are connected in circumferential relationship containing
clamping plates horizontally sliding along the rails. Said clamping plates slidably
mounted on the guide rails have suitable means actuating the clamping plates mounted
on said guide rails to predetermined positions relative each other. The clamping assemblies
have a fixed vertical shoes by which they are mounted to the guide rails and contain
a coacting movable shoes of the clamping plates. The shifting of each clamping plate
is activated by a pressure device or a pneumatic device in the form of a pneumatically
operated cylinder. A desired curvature of a wooden member can be established on the
surface of the clamping plates where, if the member is clamped to the clamping plates,
the wooden member is bent and the designed curvature is obtained. The shape for bending
is determined by locking members to which a wooden member is clamped by the clamping
plates. In another embodiment of this known solution, the clamping plates are moved
along the guide rails by means of a screw mechanism fitted to each clamping assembly.
In this known solution safety shields are provided to prevent uncontrolled release
of a wooden member as a result of its resilience. In this know solution it is possible
to obtain different bend angles of a wooden member by moving the clamping plates along
the guide rails, the length of which is provided by the whole required series of types
of bent members on a semicircular working surface of the table covered by the length
of the radially extending guide rails.
[0006] In a number of known solutions the bending profile of a laminated wood element is
obtained by clamping this element to the previously made mould, the working surface
of which has a shape corresponding to the shape of the final product. Within one process
the final element is bent and adhesive-coated slats are pressed here by being clamped
to the mould surface. This means that for different bending profiles and the pressing
of the final element, forms with appropriate bending profiles need to be previously
prepared. However, a mould prepared for one profile cannot be used for a differently
curved wooden element.
[0007] The purpose of the invention is to develop one device for bending with simultaneous
pressing laminated wood bent elements with different bending profiles. The device
is to enable the manufacture of not only arches but also bent elements, such as S-shaped
elements, and other shapes.
[0008] The solution according to the invention is disclosed in claim 1 and the subsequent
claim.
[0009] According to the invention, a device for the manufacture of laminated wood bent elements
comprises a working board with fixing holes and a clamps assembly attached to the
working board. Each clamp comprises a bottom beam to which a retaining plate perpendicular
to the bottom beam and a clamping plate perpendicular to the bottom beam are attached.
The clamping plate is slidably attached to the bottom beam by means of a hydraulic
cylinder. The maximum distance between the retaining plate and the clamping plate
is bigger than the width of a laminated wood element.
[0010] The fixing holes are regularly spaced on the surface of the working board, according
to the directions of the Cartesian coordinate system x, y. In addition, the bottom
beam of each clamp comprises at least one base pin rotatably and detachably mounted
in the fixing hole of the working board.
[0011] Each fixing hole in the working board preferably contains assigned parameters of
the Cartesian coordinate system x, y.
[0012] The clamp is preferably provided with an upper beam, where the bottom beam and the
upper beam are connected together at the ends by a connecting member from one side
and by a connector from the other.
[0013] The retaining plate of the clamp is attached to the connector of the clamp by means
of a position adjustment assembly of the retaining plate.
[0014] According to the invention, the device is characterised in that the position adjustment
assembly of the retaining plate is two adjustment screw mounted one above the other,
mounted in the connector of the bottom beam and the upper beam. According to the invention,
the heads of the two adjustment screws constituting the position adjustment assembly
of the retaining plate are connected together by a transmission chain.
[0015] The camping plate is attached to the clamp, in a preferred embodiment of the invention,
by means of at least one hydraulic cylinder mounted in the connecting member of the
bottom beam and the upper beam.
[0016] In another preferred embodiment of the invention, in the clamp the clamping plate
can be attached to the clamp by means of piston rods of two hydraulic cylinders mounted
one above the other in the connecting member of the bottom beam and the upper beam.
[0017] In the solution according to the invention, a new solution of a clamp cooperating
with a working board is proposed. Each clamp contains at least one round base pin
mounted in at least one of the round holes of the working board. The same, subsequent
clamps are mounted in further holes of the working board.
[0018] The holes in the working board are arranged in the form of a regular grid of holes
along the Cartesian coordinate lines x,y, in horizontal rows and in vertical columns,
in the same distances from one another. This enables the design and computer selection
of holes in the working board where the base pins of the clamps are to be mounted.
[0019] After mounting the base pins of the clamps in holes, owing to adjustment on adjustment
screws it is possible to precisely arrange the retaining plates so that the surface
of the retaining plates of the clamps assembly reproduces the designed final shape
of a wooden element. Then, between the retaining plates and the clamping plates being
apart from each other a pack of adhesive-coated wooden slats is arranged. Then, in
all clamps the clamping plates are hydraulically moved towards the retaining plates
resulting in the pressing of individual slats into one pack, and at the same time
in the shaping of a wooden element in accordance with the designed curvatures. After
the bonding time specified in the technological process, the clamping plates are hydraulically
moved away from the retaining plates and a shaped laminated wood bent element is removed
from the clamps assembly for finishing. The clamps assembly is ready to manufacture
another, the same glued element. The clamps can also be removed from the holes in
the working board and their base pins put into other holes of the working board to
manufacture another bent element with different curvatures.
[0020] According to the invention, the working board with a regular grid of holes arranged
in horizontal rows and vertical columns along the Cartesian coordinate lines x, y
enables, at the project stage, the determination of the coordinates of the fixing
holes intended to be used for mounting another clamps. The same working board can
be used for the manufacture of wooden elements with various curvatures. On one working
board according to the invention, several wooden elements with the same or various
curvatures can also be manufactured at the same time. One bent wooden element with
large dimensions can also be manufactured on several working boards put together.
[0021] An important advantage of the solution according to the invention is the mounting
of one round base pin of each clamp in one round fixing hole of the working board.
This enables, by the rotation of the clamp on the base pin, the natural adjustment
of the proper position of the clamp with respect to the surface of a bent wooden element,
when the bending process with the simultaneous bonding process starts.
[0022] The subject of the invention is shown in the embodiment in the accompanying drawing
in which the individual figures show:
- Fig. 1 -
- the working board with the clamps assembly.
- Fig. 2 -
- part of the working board, according to Fig. 1 .
- Fig. 3 -
- a side view of the clamp.
- Fig. 4 -
- a top view of the clamp.
- Fig. 5 -
- a perspective view of the clamp.
[0023] Fig. 1 in the embodiment shows the working board 1 with the fixing holes 2. The fixing
holes 2 are arranged on the working board 1 in the Cartesian coordinate system x,y.
This means that individual fixing holes 2 are arranged in horizontal rows and in vertical
columns. In the embodiment shown in Fig. 1, the working board 1 comprises 35 horizontal
rows and 70 vertical columns of the fixing holes 2. The fixing hole 2 shown as an
example in Fig. 1 is placed in horizontal row 2 and in vertical column 46. Thus, the
board shown in Fig. 1 contains 2,450 fixing holes 2. In other embodiments the working
board 1 can have different numbers of rows and columns of the holes 2.
[0024] Distances between individual rows and between individual columns of the fixing holes
2 are the same, and the symmetry axes of the fixing holes 2 are arranged regularly,
on the theoretical Cartesian coordinate lines x,y. In this embodiment, the working
board 1 is made of layered plywood with a thickness of approx. 150 mm, but the use
of the board 1 made of a different material is not excluded in other embodiments.
[0025] Fig. 1 also shows the clamps 3 assembly, mounted in the fixing holes 2 of the working
board 1. As shown in this figure, the clamps 3 are arranged radially, where each of
them is clamped on a wooden element 4. Pressure lines 6 and return lines 7 of hydraulic
cylinders 12 of individual clamps 3 shown schematically here are supplied from the
main pressure and return line 5. The lines are connected by means of known quick couplers
to the known hydraulic fluid supply system.
[0026] Fig. 2 shows part of the working board 1 with the clamps 3 assembly from Fig. 1.
The clamps 3 are clamped on the wooden element 4, and because they are mounted in
the holes 2 of the working board 1, the wooden element 4 has taken an arched shape,
in accordance with the configuration of mounting the clamps 3 in the board 1, as designed
by the designer.
[0027] Fig. 1 and Fig. 2 show that in this embodiment the wooden element 4 is clamped in
eleven clamps 3. However, the working board 1 has a large surface with the arrangement
of the fixing holes 2, shown in Fig. 1 in the amount of 2,450 holes. By increasing
the number of the clamps 3 and mounting their base pins 17 in other fixing holes 2,
the length of the wooden element 4 being shaped can be significantly increased, and
its bending range and direction can also be freely changed.
[0028] If it is necessary to bend the wooden element 4 which is longer than the size of
the working board 1, there are no obstacles to adding another working board 1 of the
same or a different size. The board 1 in this embodiment is designed so that the distance
of the extreme rows and columns of the holes 2 from the edge of the board is half
the standard distance between the rows and columns of the holes 2. Therefore, the
putting together of two boards 1 makes that in their point of contact the distance
between the extreme rows and the extreme columns of the holes 2 in the adjacent boards
2 is the same, as on the whole surface of each of the working boards 1. This is particularly
important in the production of bent rafters for the construction industry, often of
considerable dimensions, exceeding the size of a single working board 1. Therefore,
the solution according to the invention makes it possible to add further working boards
1 to the first working board 1.
[0029] Fig. 2 shows that hydraulic cylinders of each clamp 3 have a working medium supplied
through the pressure line 6 and discharged through the return line 7.
[0030] Fig. 3, Fig. 4 and Fig. 5 show the structure of the clamp 3, according to the invention.
Fig. 3 shows a side view of the clamp 3. The clamp 3 comprises the bottom beam 8 and
the upper beam 9. The extreme parts of the beams 8,9 are connected together by the
connecting member 10 from one side and by the connector 11 from the other.
[0031] In this embodiment, two hydraulic cylinders 12 are fixed in the connecting member
10. On the piston rods 14 of the hydraulic cylinders 12 the clamping plate 13 is mounted,
perpendicular to the working board 1 and to the bottom beam 8 and to the upper beam
9 of the clamp 3. The clamping plate 13 is slidably mounted between the bottom beam
8 and the upper beam 9 on the piston rods 14 of said hydraulic cylinders 12. Thus,
the clamping plate 13 can be moved between the bottom beam 8 and the upper beam 9,
along the beams, as a result of the movement of the piston rods 14 of the hydraulic
cylinders 12. In another embodiment, one hydraulic cylinder 12 can be mounted in the
connecting member 10 and in this solution of the clamp 3, the clamping plate 13 is
mounted on one piston rod 14. With the use of a hydraulic distributor 16 in the hydraulic
system of the clamp 3, the clamping plate 13 can be moved in the clamp 3 in the direction
of the retaining plate 19 and back.
[0032] Fig. 4 and Fig. 5 show that in this embodiment the bottom beam 8 and the upper beam
9 have holes 15 allowing the shifting of the attachment point of the connecting member
10 of the two beams 8,9, if needed, resulting from significant changes in the size
of the wooden element 4. Usually this adjustment is not needed, because differences
in the thickness of subsequent wooden elements 4 is adjusted by the extension of the
piston rods 14 with the clamping plate 13. The holes 15 in the upper beam 9 cooperating
with the connecting member 10 and with the connector 11 also enable the removal of
the upper beam 9 from the clamp 3 for the removal of a finished bent element 4 and
for the placement between the plates 13,19 of a new wooden element 4 to be bent and
pressed.
[0033] The described embodiment proposes in one clamp 3 two hydraulic cylinders 12, supplied
from the same distributor 16. The hydraulic cylinders 12 work through the piston rods
14 on the clamping plate 13, in the bottom part and in the upper part of the clamping
plate 13. As a result of tests, it has been found that the use of two hydraulic cylinders
12, arranged one above the other, as clearly shown in Fig. 3, is conductive to the
uniformity of the force exerted by the clamping plate 13 over the entire width of
the wooden element 4, and thus it is conducive to the uniformity of connections of
bonded slats in the wooden element 4. This does not exclude in other embodiments the
use of only one hydraulic cylinder 12 on the piston rod 14 of which said clamping
plate 13 is fixed. It is noted that the bonding and pressing technology of wooden
elements from previously prepared slats is generally known to those skilled in the
art and as such is not a subject of the present invention.
[0034] On the second extreme end the bottom beam 8 and the upper beam 9 are connected together
by the connector 11, which in this embodiment is terminated at the bottom with the
base pin 17. The base pin 17 is a member cooperating with the selected hole 2 in the
working board 1 and is the sole member fixing the clamp 3 in the working board 1.
The clamp 3 is rotatably mounted in the hole 2 and its base pin 17 can be removed
from the hole 2 and rotatably mounted in another hole 2 of the working board 1.
[0035] In the clamp 3, in the upper part of the connector 11 in this embodiment there are
two threaded holes, one above the other. In the holes there are two adjustment screws
18. Between the bottom beam 8 and the upper beam 9, to the ends of the screws 18 the
retaining plate 19 is fixed at the ends of the screws. The arrangement of the retaining
plate 19 in a particular place along the beams 8,9 can be set by turning both adjustment
screws 18. The retaining plate 19 by turning the screws 18 is set at a position appropriate
for the final shape of the wooden element 4. When a set of wooden slats with adhesive-coated
surfaces is arranged between the plates 13,19, the upper beam 9 is put on the connecting
member 10 and on the connector 11, in the clamp 3. Then, the clamping plate 13 is
hydraulically moved towards the retaining plate 19 previously put in the designed
place. Pressure is applied on the prepared wooden element 4 as a result of which the
wooden slats are glued, and a bent glued wooden element is obtained after a period
of time appropriate for the raw materials used. Then, the clamping plates 13 are hydraulically
put back and the upper beams 9 are removed from the clamps 3 and the formed laminated
wood element 4 is taken out.
[0036] To make the handling of the adjustment screws 18 easier, their heads can have the
form of known gear wheels, and in this embodiment they are connected by the chain
20 which is shown in Fig. 3, Fig. 4 and Fig. 5. Thus, according to the invention the
turn of one adjustment screw 18 causes the simultaneous turn of the other adjustment
screw and the uniform shift of the retaining plate 19 along the beams 8,9 towards
the planned position of the retaining plate 19 over the length of the clamp 3.
[0037] The arrangement of the fixing holes 2 on the board 1 in the Cartesian coordinate
system x,y has made it possible to determine the position of the base pin 17 of each
clamp 3 in the hole described by the number of the horizontal row x and the number
of the vertical column y in the Cartesian coordinate system x,y by the computer. However,
the computer program for this purpose is not a subject of the present invention.
[0038] The adoption of the specified space between the horizontal rows and the vertical
columns of the fixing holes 2 in the working board 1 has made that the range of adjustment
of the retaining plate 19 in each clamp 3 should cover the whole distance between
the adjacent fixing holes 2 in the working board 1, both in lines consistent with
the course of the rows and columns of the holes 2, and in oblique directions between
the adjacent holes 2. This has made it possible to arrange the retaining plates 19
of subsequent clamps 3 virtually at every point of the working board 1. To mount the
base pins 17 of the clamps 3, the fixing holes 2 which are the most similar to the
designed shape of the wooden element 4 are used. The final, exact arrangement of individual
retaining plates 19 of subsequent clamps 3 is performed by the turn of the adjustment
screws 18. When the retaining plates 19 are arranged, according to the designed shape
of the wooden element 4, a set of adhesive-covered slats are arranged between the
retaining plates 19, and the clamping plates 13 of subsequent clamps 3. The clamps
3 are previously mounted with their base pins 17 in the holes 2 of the working board
1, according to the designed shape of the wooden element 4.
[0039] The proposed solution according to the invention, where the base pin 17 of each clamp
3 can be easily removed from the hole 2 in the board 1 and mounted in another hole
2 of the same or adjacent working board 1 makes it possible to arrange the clamps
assembly 3 virtually in every configuration to produce a wooden element 4 of any bending
shape of this element in the x,y plane of the Cartesian coordinate system. The solution
according to the invention also enables the production on one working board 1 two
or more wooden elements 4 of the same or different bending shapes at the same time.
Two or more clamps 3 assemblies can be used here. It is also possible to put together
more than one working board 1 to produce the wooden elements 4 with dimensions exceeding
the size of a single working board 1.
List of designations in the drawings
[0040]
- 1.
- Working board.
- 2.
- Fixing hole.
- 3.
- Clamp.
- 4.
- Wooden element.
- 5.
- Pressure and return line.
- 6.
- Pressure line.
- 7.
- Return line.
- 8.
- Bottom beam.
- 9.
- Upper beam.
- 10.
- Connecting member.
- 11.
- Connector.
- 12.
- Hydraulic cylinder.
- 13.
- Clamping plate.
- 14.
- Piston rod of the hydraulic cylinder.
- 15.
- Hole.
- 16.
- Distributor.
- 17.
- Base pin.
- 18.
- Adjustment screw.
- 19.
- Retaining plate.
- 20.
- Chain.
1. Maschine zur Herstellen vom gebogenen Leimbindern, mit Arbeitsplatte (1) mit Befestigungslöchern
(2) und an der Arbeitsplatte (1) befestigte Klemmsatz (3), wobei jede Klemme (3) untere
Balken (8) enthält, an der Druckplatte (19) angebracht ist, der senkrecht zur unteren
Balken gerichtet ist, und senkrecht zur unteren Balken gerichtete Klemmplatte (13),
wobei die Klemmplatte (13) in der Klemme (3) gleitend montiert ist, wobei der maximale
Abstand zwischen Druckplatte (19) und Klemmplatte (13) größer ist als die Breite des
Leimbinders, wobei die Befestigungslöchern (2) an der Arbeitsplatte (1) regelmäßig
eingerichtet sind, und jede Klemme (3) mindestens ein Grundbolzen (17) enthält, der
drehbar und lösbar im Befestigungsloch (2) an der Arbietsplatte (1) gelagert ist,
wobei jedes Befestigungsloch (2) an der Arbietsplatte (1) ihm horizontal und vertikal
zugewiesene Zeilennummer enthält, und die Klemme (3) der obere Balken (9) enthält,
und die Druckplatte (19) ist mittels der Satz für die Einstellung der Sitzplätze der
Druckplatte (19) in dem Bindeglied (11) des unteren (8) und oberen (9) Balken von
der Klemme (3) montiert, dadurch gekennzeichnet, dass die Befestigungslöchern (2) an der Arbeitsplatte (1) regelmäßig nach den Anweisungen
des Kartesisches Koordinatensystem (x, y) angeordnet sind, wobei die Klemmplatte (13)
in der Klemme (3) mittels mindestens eines Hydraulikzylinders (12) gleitend montiert
ist und der Satz für die Einstellung der Sitzplätze der Druckplatte (19) ist von zwei
Einstellschrauben (18) gebildet, die in dem Bindeglied (11) übereinander eingesetzt
sind, wobei in dem Satz für die Einstellung der Sitzplätze der Druckplatte (19) die
Schraubenköpfe von den Einstellschrauben (18) durch eine Antriebskette (20) verbunden
sind.
2. Vorrichtung gemäß Anspruch 1., dadurch gekennzeichnet, dass in der Klemme (3) die Klemmplatte (13) an dem Bindungselement (10) mittels der Kolbenstande
(14) von zwei im Bindungselement (10) übereinander montierten Hydraulikzylindern (12)
befestigt ist.