Description

Gluing apparatus for gluing ends of wood veneer together

This invention relates to a gluing apparatus for gluing wood veneer strips together, and a process for gluing together ends of wood veneer strips.

The State of the art

BE 1014641 describes a process and an apparatus for gluing cut ends of two wood veneer strips together. According to this patent, the process comprises the following steps:

- Two wood veneer strips of a certain length and width are arranged next to one another in the longitudinal direction, such that the opposite ends of each strip are at a certain distance from one another.

- The two opposite ends of the strips are cut, whereby sharp tooth-shaped ends are obtained.

- A strip of glue is placed in the space between two opposite cut ends of the veneer strips. - The two opposite cut ends are moved together, such that the teeth of one end are inserted into the notches of the other end.

- The glued ends are worked with a means of exerting pressure to ensure an even adhesion of the glue.

Description of the Invention

The present invention relates to a gluing apparatus to improve the gluing of opposite cut ends of wood veneer strips together, with regard to speed and/or the properties and/or quality. Moreover, the gluing apparatus can be constructed as a detachable cassette that can be placed in an existing installation for manufacturing rolls/sheets of wood veneer. The invention or embodiments of the apparatus/process according to the invention are suitable for solving one or more problems and/or are suitable for one or more improvements in the production of wood veneer and/or for improving the quality of the wood veneer and/or the glue junction or binding means between two ends of adjacent wood veneer strips :

- embodiments of the invention suitable for gluing together veneer strips having possibly different thickness, and/or - embodiments of the invention suitable for achieving glue joints or bonds resistant to temperature and/or water and/or humidity and/or chemicals and/or solvents, and/or

- embodiments of the invention enabling to add colour within the glue or joint, and/or - embodiments of the invention improving the production of loop by fleece lamination, and/or

- embodiments of the invention preventing or reducing differences of colour in the glued wood strips, and/or

- embodiments of the invention preventing or reducing torsion or bending between adjacent glued wood strips, and/or

- embodiments of the invention preventing or reducing the formation of cracks or splits within the wood strips, especially at the level of the glued lines, and/or

- embodiments of the invention using simple in feed table(s) for feeding wood strips and/or out feed table for transport of glued strips, and/or - embodiments of the invention enabling an easier removal of excess glue present on the glue band support, by moving the band support to and/or in front of a glue drying unit, before submitting the band provided with excess glue to a scrapping means, and/or

- embodiments of the invention enabling to prevent or reduce friction of the support band during the transversal movement of said support band with respect to the strips to be glued or glued together, and/or the movement of the glued strips with respect to said support band, and/or

- embodiments of the invention enabling a better removal of waste from the cut operation from the pusher plate(s), and/or - embodiments of the invention enabling a take over of forces by cylinders and/or springs of the pusher plate(s), and/or - etc.

A first embodiment of the invention is an improved gluing apparatus for gluing together the ends/sides of wood veneer strips, in which the improved apparatus comprises a carrier that is flexible such that the carrier can at least be deformed between a substantially flat position and a bent position to move the glue strip upwards, and a means to bend the carrier to move the glue strip upwards.

The invention relates to a gluing apparatus for gluing an end of a first wood veneer strip to an end of a second wood veneer strip, in which the ends of the first and second wood veneer strips are cut into the form of a series of sharp teeth next to one another, and whereby the tooth profile of the end of the first wood veneer strip perfectly matches the tooth profile of the end of the second wood veneer strip, such that the teeth of the tooth profile of the first wood veneer strip can be perfectly inserted into the notches between the teeth of the tooth profile of the second wood veneer

The gluing apparatus is intended to be mounted on a moving table in order to move the tooth profiles of the ends together. The gluing apparatus at least comprises:

- a carrier for a strip of glue,

- a means adapted for placing the carrier with the glue strip between the ends of the first and second wood veneer strips, so that after moving the tooth profiles of the ends the one towards the other (converging movement) by means of the moving table, the tooth profiles of the ends inserted into one another are glued together, - a means adapted for pressing and/or for treating the glue for curing and/or drying and/or hardening the glue located between the tooth profiles inserted into one another, preferably for thermally treating and/or treating with rays (such as UV treating) the glued tooth profiles inserted into one another.

According to the invention the gluing apparatus also at least comprises:

A. An elongated pressure bar that is at least partially moveable (for example in a direction that is substantially perpendicular to the direction of the converging movement of the tooth profiles of the ends of the wood veneer strips to be glued together) at least between:

- a first position in which the glue strip is located under the pressure bar, without the pressure bar touching or contacting the glue strip, and

- a second position in which the pressure bar or a part of it at least partially touches the glued tooth profiles inserted into one another, possibly with interposition of a paper or film layer,

B. A carrier that is flexible such that a portion of the carrier can at least be deformed between a substantially flat position and a bent position adapted to move the glue strip deposited on said portion upwards,

C. A means adapted to bend said portion of the carrier in order to move the glue strip upwards, and

D. A means adapted to move the pressure bar or a part of it between said at least first and second positions.

The gluing apparatus of the invention has advantageously one or more of the characteristics disclosed in the attached claims.

According to the invention, the gluing apparatus also preferably at least comprises:

A. An elongated rotatable pressure bar that can be turned around an axis that is substantially perpendicular to the direction of the converging movement of the tooth profiles of the ends of the wood veneer strips to be glued together, between: - a first position in which the glue strip is located under a first part of the pressure bar, without this part of the pressure bar touching/contacting the glue strip, and

- a second position in which a second part of the pressure bar at least partially touches the glued tooth profiles inserted into one another.

B. A carrier that is flexible such that the carrier can at least be deformed between a substantially flat position and a curved position in order to move the glue strip upwards.

C. A means for bending the carrier in order to move the glue strip upwards, and

D. A means adapted at least for turning or rotating the pressure bar.

According to an embodiment the first part of the pressure bar is longitudinal profile with a central groove intended to be above the glue strip in the first position of the pressure bar.

Preferably the first part of the pressure bar is a profile that is mounted in a slot of the pressure bar, whereby this profile can be detached or removed from the pressure bar.

According to an advantageous embodiment, the profile is mounted in a slot, whereby the profile and/or the pressure bar at least comprises a means for adjusting the position of the profile with respect to the axis of rotation of the pressure bar.

According to one detail of an embodiment, the gluing apparatus has a means for removing the pressure bar from the carrier after gluing the ends of the first and second wood veneer strips together.

The gluing apparatus is preferably provided with or connected to a transport system for moving strips glued together. According to a detail of an embodiment, the gluing apparatus is provided with a system for providing glue on the carrier so as to deposit on said carrier a glue strip, preferably for moving the carrier provided with the glue strip below the pressure bar. Preferably, the system is adapted for providing glue on the carrier and/or for moving the carrier provided with the glue strip below the pressure bar, most preferably at least during the moving of strips glued together.

According to another detail of an embodiment, the pressure bar has a means for heating at least the second part of the pressure bar and/or a means suitable for emitting rays suitable for curing, drying or hardening glue.

In case of curing or hardening of glue by increase of temperature (for example by heating the glue at a temperature comprised between 120°C and 300 ⁰ C) for a too long period, bending of the glued strips and/or splits in the glued strips can occur. In order to prevent or reduce said problem or problems, the apparatus can be provided with a humidifier system. The humidifier system is forexample adapted for humidifying at least partly the glued strips, after the curing and/or hardening of the glue, preferably at least partly before and/or during the transport of the strips glued together by the transport system. The problem of bending and/or splits can also possibly be at least partly solved and/or reduced by using glues which can be cured and/or hardened at low temperature, for example at temperature lower than 100°C, and/or by using glues which can be hardened or cured within an extremely short period. For said purposes, catalyst(s) and/or accelerator(s) or accelerating agent(s) for the curing and/or hardening, and/or additive(s) can be added to the glue and/or applied onto the glue and/or applied onto the carrier before depositing the glue onto the carrier in order to reduce the curing and/or hardening time and/or in order to reduce the curing and/or hardening temperature.

The additive(s) is/are for example suitable for chemically reacting and/or for starting a chemical reaction. According to one additional detail of an embodiment, the second part comprises a means for compensating for the thickness of the ends of the first and second wood veneer strips placed next to one another in the second position of the pressure bar. Preferably, the means for compensating for the thickness comprises a rubber element that is at least heat conductive.

For example, the means for compensating for the thickness is profiled such that when the means touches the two ends, a force is exerted on these ends in order to push and/or move these ends towards one another. In particular, the means for compensating for the thickness has a surface that is intended to be directed at the ends of the wood veneers strips, whereby the means contains a central part that between two side elements or series of side elements, whereby the side elements form or contain projections with respect the central part, whereby the central part preferably has a central groove to enable movements of a first side element or series of side elements towards the second side element or the second series of side elements.

According to the invention, the apparatus can be fitted with a control system that contains a number of webcams or cameras or optical lenses to at least send images of the cut ends to a computer system. Preferably, the computer system is suitable for processing images of the cut ends in order to compare certain parameters (such as position of the teeth, angle difference, etc) of these images to reference parameters, and to issue instructions to one or more components of the gluing apparatus as a function of the comparison/difference with respect to the reference parameters.

According to the invention the apparatus can also comprise a control system receiving from one or more webcams, cameras and/or optical lenses, one or more images or views, advantageously one or more enlarged images or view (for example enlarging factor of more than 5, advantageously equal or more than 10, for example comprised between 10 and 50) of the glue strip deposited on the carrier, before the ends of the wood veneer strips being glued together, advantageously before the movement of the ends the one towards the other. This is advantageous, as in case the glue strip is not adequate, for example due to a lack of glue at one or more portions of the glue strip, for example glue thickness too low at one or more portions of the glue strip, the control system can detect said defect, for example by image analysis, whereby preventing the movement of the ends of the wood veneer strips into the glue strip, and whereby controlling the deposit of additional glue and/or the deposit of a new glue strip on the carrier and the movement of said carrier for placing said new glue strip between the two ends of wood veneer strips to be glued together.

The invention also relates to a gluing unit that contains a gluing apparatus according to the invention, as well as at least a moving table for moving the tooth profiles of the ends of the wood veneer strips together. The gluing apparatus is preferably moveable and/or detachable with respect to the moving table.

Preferably the moving table is fitted with:

- A first element adapted to hold a part of a first wood veneer strip.

- A second element adapted to hold a part of a second wood veneer strip, and - A means for simultaneously manoeuvring the above-mentioned first and second elements, in which this means at least comprises an eccentric that is connected to the first and second elements, by a first rod and a second rod respectively. The rotation (back and forth) of the eccentric can be implemented by means of a cylinder, a motor, etc., whereby said rotation of the eccentric generates a relative movement between the said first and second elements.

According to an embodiment of the gluing unit, it is fitted with one or more cutting dies to cut the ends of the first and second wood veneer strips to a obtain the sharp tooth-shaped ends (ends to be glued thereafter together). Preferably the unit has a basic element: - that is connected to one or more lower blocks that are fixed with respect to the basic elements when cutting the ends, and

- that is connected to a means to push the cutting die or dies down in the direction of one of the under blocks to cut the ends of the wood veneer strips.

For example, the basic element has one or more removal elements that are intended to work together with the die or dies to remove the waste from the cutting of the ends of the wood veneer strips from the die or dies.

In an embodiment the basic element has one or more moveable pressure elements (for example pusher plates) to push and hold parts of the wood veneer strips against one or more lower blocks, at least while cutting the ends. Preferably the pressure elements or pusher plates are connected to the basic element by at least a number of springs and at least a cylinder, whereby the springs exert pushing forces so that the bottom surface of each pressure element is parallel to the top surface of each lower block, whereby a part of the wood veneer strip is intended to be pulled out from between the bottom surface and the top surface.

According to a detail of an embodiment, the unit has a control system that comprises a number of webcams or cameras or optical lenses to at least send images of the movable components to a computer system.

In particular, the computer system is suitable for processing images of the movable components in order to compare certain parameters of these images with reference parameters, and to issue instructions to one or more components of the gluing unit as a function of the comparison/difference with respect to the reference parameters.

The invention further relates to a moving table with cutting die/dies, whereby the moving table is fitted with:

- a first element adapted to hold a part of a first wood veneer strip, - a second element adapted to hold a part of a second wood veneer strip, and - a means for simultaneously manoeuvring the above-mentioned first and second elements, in which this means at least contains an eccentric that is connected to the first and second elements, by a first rod and a second rod respectively, and/or that is fitted with a basic element - that is connected to one or more lower blocks that are fixed with respect to the basic element at least when cutting the ends, and

- that is connected to a means to push the cutting die or dies downwards in the direction of one of the lower blocks to cut the ends of the wood veneer strips. For example, the basic element has one or more removal elements that are intended to work together with the die or dies to remove or expel the waste from the cutting of the ends of the wood veneer strips from the die or dies.

The invention further relates to a gluing apparatus for gluing together ends or edges of wood veneer strips, in which the gluing apparatus contains a pressure bar that is movable with respect to a glue carrier, in which the pressure bar has a groove or channel, a pressure profile that is at least partially mounted and movable in the above-mentioned groove or channel, and a means to connect the pressure profile to the pressure bar, whereby the pressure bar also has a pushing element whereby the movement of the pressure profile at least partially acts against the force of the pushing profile, and whereby the pressure profile is at least partially deformable when the pressure profile is pressed on the ends to be glued together, whereby at least a pushing force is exerted to push the glued ends of the wood veneer strips towards each other.

The pushing element is a spring for example.

The pressure profile preferably comprises two components adapted to move towards each other when the pressure profile is moved in the direction of the base or bottom of the groove or channel. According to an embodiment, the groove or channel has side walls that are slanting, whereby an angle of 30° to 150° inclusive (preferably between 60° and 120°) is formed between the above-mentioned side walls or between the planes in which extend said side walls respectively. The pressure profile or components thereof has/ have side surfaces that are intended to slide along side walls of the groove or channel.

According to an advantageous embodiment, the pressure profile comprises two components that each contain teeth, in which the teeth of a first component are adapted to be moved between the teeth of the other component.

The teeth of the first component are preferably profiled such that these teeth only exert a force on a wood veneer strip, while the teeth of the second component are preferably profiled to only exert a force on another wood veneer strip.

Another gluing apparatus according to the invention for gluing together ends or sides or edges of wood veneer strips comprises a pressure bar that is movable with respect to a glue carrier, whereby the pressure bar has a groove or channel, a pressure profile that is at least partially movable and mounted in the above- mentioned groove or channel.

The pressure profile comprises two parts located next to one another that are driven separately, whereby a first part is intended to push on a first end of a strip, while a second part of the pressure profile is intended to press on the end of another wood veneer strip. The second part is preferably suitable for exerting a pushing force from the end of the second wood veneer strip on the end of the first wood veneer strip while gluing the above-mentioned ends together. The second part of the pressure profile is preferably suitable for moving the end of the second wood veneer strip to the end of the first wood veneer strip, when the second part of the pressure profile touches the end of the second strip. Preferably the first part of the pressure profile is intended to hold an end of the first wood veneer strip between first part of the pressure profile and the carrier. The first part of the pressure profile pushes on a part of the carrier that does not have a glue strip.

According to an embodiment, the gluing apparatus comprises fingers to hold the ends of the strips to be glued together. These fingers are preferably adjustable, such that the first wood veneer strip can be thicker than the second wood veneer strip. Cylinder(s) and/or spring(s) is/are for example used to press the ends of the strips between two opposite fingers.

The gluing apparatus according to embodiments of the invention thus has the following advantages:

- Possibility to adjust the height of the glue - Possibility to exert even pressure on the wood veneer strips

- Possibility to glue strips of different thicknesses together.

The invention also relates to a machine for gluing wood veneer strips together breadthways and/or lengthways in which one or more gluing apparatuses as described above are used.

The invention further relates to a process for gluing an end of a first wood veneer strip to an end of a second wood veneer strip, whereby the ends of the first and second wood veneer strips are cut in the form of a series of sharp teeth located next to one another, and whereby the tooth profile of the end of the first wood veneer strip perfectly matches the tooth profile of the end of the second wood veneer strip, so that the teeth of the tooth profile of the first wood veneer strip can be perfectly inserted in the notches between the teeth of the tooth profile of the second wood veneer strip, in which the gluing of the cut end of a first wood veneer strip to the cut end of a second wood veneer strip is done in a gluing apparatus according to the invention, in which the process comprises at least the following steps:

A. Movement of the carrier to place a strip of glue under the first part of the pressure bar, whereby the glue strip extends between the cut ends of the wood veneer strips located away from one another.

B. The bending of the carrier so that strip of glue is moved upwards.

C. The movement, preferably simultaneously movement, of the cut ends towards the glue strip whereby the teeth of an end are perfectly glued in the notches between the teeth of the other end. D. The movement, preferably rotation, of the pressure bar to press the glued ends together.

E. The movement of the pressure bar to remove the pressure bar from the glued ends.

F. Optionally, but preferably, unbending of the carrier.

The details and characteristics of advantageous embodiments according to the invention will arise from the following description, which also refer to the attached drawings.

Brief description of the drawings

These drawings show:

- Figure 1 steps involved in gluing the ends of two wood veneer strips together.

- Figure 2 schematic view of a gluing unit with moving table and cutting dies. - Figure 3 a cross-section along line III-III of the unit of figure 2 showing details of the gluing apparatus.

- Figures 4 A - 4F cross-sections of the pressure bar of the gluing apparatus in various stages of the gluing of two ends of wood veneer strips together.

- Figure 4G a cross-section of the pressure bar during the step of moving of the strips glued together, while the carrier or portion of the carrier provided with a new glue strip is moved, said new glue strip being intended for the next gluing cycle of two cut ends of wood veneer strips.

- Figures 4H and 41 cross-sections of the pressure bar provided with a system for feeding/depositing a paper and or film for covering at least partly the cut ends glued together,

- Figures 5 and 6 side views of the pressure bar.

- Figures 7 and 8 views of the mechanism to drive the moving table.

- Figure 9 a cross-section along the line IX - IX of figure 2.

- Figures 1OA - 1OE various steps of the cutting of an end of a wood veneer strip. - Figure 11 a screen on which various images of the process are shown.

- Figures 12A and 12B top views of the ends before and after the gluing of them.

- Figures 13A and 13B cross-sections of a pressure bar that can also operate without pivoting around an axis 16.

- Figures 14 A and 14B cross-sections of another embodiment of a pressure bar. - Figures 15 A, 15B and 15C cross-sections of an additional embodiment of a pressure bar.

- Figures 16 and 17 schematic views of processes in which at least a pressure bar is used according to the invention during the gluing of two sides of wood veneer strips, and - Figures 18 A and 18B cross-sections of pressure bar that can also operate without pivoting or turning.

Description of preferred embodiments

The installation schematically shown in figure 2 comprises:

* a gluing apparatus 1

* a left cutting unit 2 with cutting die 3

* a right cutting unit 4 with cutting die 5

* one or more tables 6 to move the wood veneer strips when gluing the ends together. The process for gluing the ends of wood veneer strips together comprises the following steps:

- Step 1 A wood veneer strip BF 1 is moved to the right to place an end of it under the cutting die 3.

A wood veneer strip BF2 is moved to the left to place an end of it under the cutting die 5.

These movements can be done by the tables 6 and an eccentric 35. The implementation of wood veneer strip(s) can also be realised by rollers that are driven by motor(s), linear motor(s), etc.

- Step 2

The ends of the wood veneer strips are cut by the dies 3, 5. The cut ends have a tooth profile (see figures 1OA - 10D).

- Step 3

A carrier 9 for a strip of glue 10 is moved to place the glue strip under a first part 7 of the pressure bar 8. Step 3 can be done before, after or during the implementation of step 2. Steps 2 and 3 are preferably done simultaneously.

Step 3 can also be carried out at least partly during the moving away of the strips glued together (see for example Figure 4G). This is advantageous as a new glue strip can be placed for a new gluing cycle or step, before the end of the cutting of the ends of the strips to be glued together. This is advantageous as it enables to save time, for example 1 to 2 seconds per complete cycle, with respect to a total cycle time of 6 to 10 seconds, when all the steps are carried out the one after the other. - Step 4

The carrier 9 is bent so that the strip of glue is moved upwards. The strip of glue is now substantially at the level of the wood veneer strips that have to be glued together.

- Step 5

The cut ends of the wood veneer strips are moved together by the moving table 11, whereby the teeth of one end are inserted and glued in the notches between the teeth of the other end.

- Step 5bis (optional)

depositing a paper or film at least partly above the teeth of one end inserted in the notches between the teeth of the other end. Said paper or film can be provided or not with gluing means or layer. Said paper or film can be fed on the inserted cut ends from a removable cassette, whereby the cassette can easily be replaced by another when the cassette is empty or when another type of paper or film has to be fed.

Said paper or film can be pressed on the cut ends during the curing or hardening of the glue. Said paper or film can form a protection layer for preventing the gluing or adherence of a part or portion of the pressure bar with the glued cut ends.

Said paper or film can optionally removed or tear off after the curing or hardening of the glue, for example during the moving away of the glued cut ends from the gluing apparatus (Step 8).

Said paper or film (removable or not after curing or hardening of the glue) can possibly be provided with one or more information (for example, information relating to the production, name of the producer, trademark, lot number, etc.) and/or can possibly be adapted for later printing of one or more of said information. - Step 6

The pressure bar 8 is moved (for example turned - arrow R or moved downwards

Figure 18), such that a (second) part 17 of the pressure bar touches the glued ends and exerts a pressure on them. The (second) part 17 is heated to accelerate the setting of the glue.

The rotation of the pressure bar can also be avoided by using a pressure bar whose profile 17 is moveable with respect to the pressure bar and/or by using a pressure bar moveable as a whole towards the cut ends to be glued together.

When the pressure bar or the part 17 exerts a pressure on the glued ends, a pressure is then also exerted on the carrier 9, such that this carrier is bent less and/or returns to its initial position (the carrier is substantially in a plane).

- Step 7

The carrier 9 is returned to its unbent position. The pressure bar is turned or moved, such that the pressure bar is removed from the ends and no more exerts pressure on the glued cut ends.

- Step 8

The glued ends of the two strips are moved to place a free end of the glued strips under the die 5. A new wood strip can then be introduced, with its end under the die 3. Steps 1 to 7 inclusive can be further executed, such that a roll of glued strips can be manufactured.

Step 3 is advantageously at least partly carried out during step 8, for example from the end of the end 7. -Step 9 (optional)

The cut ends glued together are possibly humidied. Said humidification step can possibly carried out (partly or not) carried out at the end of step 6 and/or in step 7 and/or in step 8.

Figure 3 is a view of the gluing apparatus 1.

This gluing apparatus 1 comprises a system 11 to make a carrier belt 9 move between guide rollers (preferably Teflon coated), such that the belt 9 (preferably Teflon coated on which the glue strip has to be placed. The belt can also be a steel belt, preferably a stainless steel belt.) runs along various units of the gluing apparatus. The gluing apparatus contains a unit 13 for applying glue, advantageously substantially substantially liquid glue, to the carrier belt 9. The application of the glue to the belt is done during the movement of the belt 9 in the direction of the pressure bar 8. The system also comprises a unit 14 to deform the flexible carrier belt (e.g. by using air, by moving the lateral sides of it towards one another, etc), such that the central part of the belt 9 is moved (upwards in the figures) towards the pressure bar 8. When gluing the two cut ends of the wood veneer strips, the carrier belt 9 is no longer moved. After the gluing operation, the carrier belt is moved to a unit 15 to remove the waste glue from the carrier belt 9, for example by using one or more brushes. For facilitating the removal of excess glue present on the carrier belt 9 (to be removed in unit 15), the apparatus or the installation is provided with a unit 15ter for curing or hardening the waste glue present on the carrier belt before said waste glue being treated in unit 15. The unit 15ter can also be a unit for treating waste glue with one or more solvents and/or one or more chemical agents.

The belt 9 can be an endless belt. This belt 9 can also, in an embodiment, be a single-use belt that already has a glue strip, such that the gluing apparatus does not have to have a system for applying glue to the belt, a system for removing waste glue from the belt, etc. The belt can also be made of silicone paper.

According to an advantageous embodiment, the carrier is a steel belt (preferably stainless steel belt) that is flexible.

According to another embodiment, the carrier is a pre-glued carrier.

The pressure bar 8 is advantageously mounted on a rotary shaft 16 whereby the turning of the shaft 16 is driven by a motor and/or a cylinder. The pressure bar can turn (for example 90°) between a first position in which the first part 7 is directed downwards (i.e. the first part is opposite the carrier belt 9), and a second position in which the second part 17 is directed downwards (opposite the carrier belt 9).

Preferably the rotary shaft 16 is mounted in vertical slots such that the rotary shaft 16 can be moved vertically to adjust and/or increase the distance between the pressure bar 8 and the carrier 9 after gluing the ends together.

The first part 7 is a profile that is inserted into a slot 18 of the pressure bar 8. The profile 7 can preferably be detached from the bar 8. The profile 7 is connected to the pressure bar 8 by a means to adjust the position of the profile 7 with respect to the rotary shaft 16. The profile 7 has two longitudinal teeth 19, between which there is a central groove 20. The profile 7 preferably has a non-stick layer and preferably acts to equalise the veneer glue thickness. The profile 7 can be part of a system for delivering paper or film for covering the glued cut ends.

The glue strip 10 that is moved under the pressure bar 8 by the carrier belt 9 is opposite or in front of the groove 20. As a result of the rotation of the pressure bar, a tooth 19 of the profile 7 can touch the glue strip, if the glue strip is too thick.

The second part 17 comprises a rubber profile 21 that is inserted in a slot 22 of the pressure bar. The profile 21 is made of a heat conductive material, such that heat can be conducted from a heating element 23 to the glue while gluing the ends together. The heating element is used to accelerate the setting and/or curing and/or hardening of the glue, as soon as the teeth of the ends of the strips are inserted into one another. The profile 21 is adapted to compensate for a possible difference of thickness between the ends. The profile 21 contains side projections 24, 25 between which is a central part 26 with a groove 27. The groove 27 is used to push the side projections 24, 25 together when the profile 21 pushes on the ends of the wood veneer strips. By pushing the ends of the wood veneer strips towards one another, the teeth of an end of one wood veneer strip are correctly and neatly pushed into the notches between the teeth of the other end of the other wood veneer strip.

The gluing apparatus also preferably comprises a heating element 9bis that forms a support for the carrier 9 when the pressure bar pushes on the carrier and the ends of the wood veneer strips. The heating element is used to accelerate the setting, curing or hardening of the glue.

The pressure of the bar 8 on the glued cut ends of the wood veneer strips during the gluing step and/or curing, hardening or setting step of the glue can be controlled by a cylinder (which for example control the position of the axis 16). The pressure can possibly be given by the cutting die cylinder(s) or cylinder(s) moving the cutting die(s) of the installation. For example, the pressure can be controlled by adjusting the difference of level between the cutting position and the press position of the upper bar 67.

Figures 13 A and 13B are cross-sections of a pressure bar that can also operate without pivoting around an axis 16.

hi the embodiment of Figure 13, the profile 17 has a central longitudinal opening 90 in which a pressure plate 91 can be moved by a cylinder 92. When applying glue under the pressure bar 8, the pressure plate is move upwards, such that a rather longitudinal recess is formed. This recess is opposite the glue carrier 9. The glue strip 10 is intended to be below or partially in the recess after bending the carrier 9.

The cylinder 92 then exerts a force on the pressure plate 91, such that the glued ends of the wood veneer strips are pressed together between the carrier 9 and the pressure plate 91 (see figure 13B).

The pressure plate 91 is preferably linked to a heating element 9bis to accelerate the setting of the glue.

In the embodiment of Figures 14A and 14B, the pressure bar 8 can be moved with respect to the glue carrier 9 by a pressure cylinder. The pressure bar 8 comprises a groove 93 in which a profile 94 can move against the action of a spring 95.

The profile 94 has slanting sides 96 that slide along the slanting sides of the groove or channel 93 when moving the profile 94 with respect to the bar 8.

The profile 94 is at least partially deformable. For example, the profile is made of rubber and/or a foam material. According to an embodiment, the profile 94 has two separate elements 97, between which a rubber element is stretched. The rubber element 98 has a central slot 99 to enable movements between the separate elements 97.

When applying a glue strip under the pressure bar 8, the profile 94 is partially outside the groove 93. In this position the slot 99 of the rubber element 98 is open. The carrier 9 is bent in order to place the glue strip in the vicinity of the slot 99.

After moving the ends of the wood veneer strips towards one another, the pressure bar 8 is moved downwards such that the profile 94 touches the glued ends. The profile 94 then moves in the groove or channel 93, such that the rubber element 98 is deformed. As a result of this deformation, a force is exerted on the glued ends in order to move or push these ends together. By moving the profile 94 in the groove or channel 93, the slot 99 is at least partially closed (See figure 14B).

In the embodiment of figure 15 A, the pressure profile comprises two components 120, 121, that move towards one another when the pressure profile is moved in the direction of the base of the groove or channel 93 of the pressure bar 8.

The groove or channel has side walls 122, 123 that are slanting, such that an angle α of around 90° is formed between the above-mentioned side walls 122, 123 (angle defined between the planes comprising said side walls).

The components 120, 121 exhibit side surfaces 124, 125 that are intended to slide along side walls 122, 123 of the groove or channel in order to bring about relative movements between the components 120, 121.

Each component has a tooth profile 126, \26bis that is profiled such that the teeth 130 of a component 120 can be moved between the recesses between the teeth of the tooth profile of the other component when the side surfaces 125, 125 of the components 120, 121 slide along the side walls 122, 123 of the groove 93.

Each component has a foot 127 in order to avoid a component dropping out of the groove 93. A spring 128 exerts a pushing force on the foot 127 of each component.

Each component 120, 121 has a lower surface 129 that is it intended to touch a wood veneer strip.

Preferably the teeth of the tooth profiles of the components 120, 121 do not touch the glued ends of the strips.

By moving the pressure bar downwards (in the direction of the wood veneer strips), the components 120, 121 are pushed against the wood veneer strips, such that the components 120, 121 are pushed against the action of the springs 128 in the groove or channel 93 of the pressure bar 8. As a result of this vertical movement and the slanting walls of the groove and the components, the components are moved towards one another, such that an end of a strip is pushed to the end of the other strip. (Figure 15B)

Figure 15C is a partial view of the tooth profile of the components 120, 121.

According to an advantageous embodiment, the pressure profile contains two components that each have teeth, such that the teeth 130 of a component can be moved between the teeth of the other component.

Figures 18A and 18B are cross-sections of an additional embodiment of a pressure bar according to the invention.

The pressure bar of figures 18A and 18B comprises a pressure profile 200 that consists of a number of parts 201, 202, whereby each part is separately adjustable. The downward movement of each part 201, 202, and or the relative position of the lower surface of a part with respect to the lower surface of another part, is for example obtained by separate cylinders and/or springs and/or screws 203, 204. The pressure profile 200 is in a channel 205 of a cap 206 that can preferably be moved to the carrier 9 by a cylinder 207 in order to press the ends of the wood veneer strips together.

The cap 207 is connected to adjustable fingers 208, 209. A cylinder 210, 211 acts on each finger whereby a pressure difference can occur between the pressure exerted on a strip and the pressure exerted on the other strip.

The carrier 9 is similar to the carrier 9 shown in figures 4, 13 and 15. In order to obtain the bending of the portion of the carrier 9 provided with the glue strip 10 (portion located below the pressure bar 8), the carrier 9 is between two feet 212, 213, at least one of which is moveable with respect to the other.

In the embodiment shown, the two feet with fingers 212, 213 are moveable with respect to a basic element 214. The movement of the feet is preferably obtained by a separate cylinder 215, 216.

Each foot 212, 213 has a slanting surface that is intended to slide along a slanting surface of the basic element 214, when the foot is pushed upwards. By pushing a foot upwards, the carrier will be bent upwards, while a force will be exerted on a strip in order to move or push an end or side of it to an end or side of another strip.

Preferably the first part 201 of the pressure profile 200 is intended to hold an end of a first wood veneer strip between first part of the pressure profile and the carrier 9. The first part of the pressure profile has to push on a part of the carrier that does not have a glue strip.

The gluing apparatus of said embodiment thus has the following advantages: - Possibility to adjust the glue height

- Possibility to exert even pressure on the wood veneer strips

- Possibility to glue strips of a different thickness together.

The apparatus 2 also has a cooling system to avoid the glue setting when the second part of the pressure bar is not touching the ends of the strips.

The pressure bar 8 of each embodiment preferably has a means to control the compressing and pressing force.

The apparatus 2 is advantageously in the form of a cassette that can be detached from the unit by a sideways movement. This is advantageous for the maintenance of the apparatus, and for replacing an apparatus 2 by another apparatus 2, for example in case of defect, replacement of the carrier belt, etc.

The apparatus 2 can also be provided or associated to a system 500 for feeding/depositing a piece of paper or film above the glued cut ends of the wood veneer strips, advantageously before the curing or hardening of the glue. Said system 500 can also be in the form of a distinct cassette which is directly or not mounted on the apparatus or cassette 2, for example on the pressure bar 8. The system 500 is for example mounted in a removable way on the apparatus 2 or pressure bar 8, so as to be able an easy replacement thereof.

The feeding or deposit of paper/film element on the glued cut ends of the wood strips is advantageously a system 501 mounted on the pressure bar 8, preferably in a removable way. For example in Figures 4H and 41, the pressure bar 8 is provided with a system 501 for taking and holding a piece of paper or film (for example from a paper or film staple 503).

In the position of Figure 4H, the system 501 is in front of the paper/film staple or reserve cassette 503, so as to take one paper/film layer and hold said paper/film layer. Said step occurs advantageously during the curing/hardening of the glue of a previous gluing cycle. In Figure 41, after rotation of the pressure bar 8, the system 501 is located above the glue supported by the carrier 9 in which the cut ends of wood veneer strips have been pushed. The system 501 then release a piece of paper or film on the glued cut ends, before the curing or hardening of the glue. The pressure bar 8 is rotated back in its position of Figure 4H whereby pressing (by means of the part 17) the piece of paper or film 502 onto the glued cut ends, and whereby pressing the cut ends towards each other during the curing or hardening of the glue.

The system 501 can also be a stocking unit comprising for example a paper staple, and comprising a means for releasing the paper, piece by piece. Such a system can also be a system for feeding a piece of paper or film under the glue strip and/or above the glued cut ends of the wood strips.

According to an embodiment a piec of paper or film is deposited onto the carrier before and/or (preferably) during the deposit of glue on the carrier.

The apparatus 2 can have (a) pressure system(s), and/or means to move the pressure bar or component(s) of it.

The apparatus 2 can be used to with various glues, for example two-component adhesives, fusion adhesives, hotmelt glues, etc. Glue means also any composition suitable for generating bonds between the cut ends of two wood veneer strips inserted the one into the other.

Thus a cassette 2 can be used in existing units to glue ends of wood veneer strips, for example in a unit as described in BEl 014641. The gluing of wood veneer strips can be done to connect a series of strips lengthways and/or breadthways.

Various positions of the rotating pressure bar 8 are shown in figures 4A to 4F inclusive.

In Figure 4B, the pressure bar 8 and the carrier 9 are away from each other, whereby preventing direct contact of the part 7 with the glue strip 10 while the carrier 9 is moving (transversely with respect to the direction of movement of the cut ends the one towards the other) . In Figure 4C, the portion of the carrier 9 under the part 7 of the pressure bar is bent, whereby the glue strip 10 is moved upwards (at the level of the cut ends of the wood veneer strips). The wood veneer strips are then moved the one towards the other, so that the teeth of one end of a wood veneer strip are inserted into the notches between the teeth of the end of the other wood veneer strip, and inversely (Figure 4D). The pressure bar 8 is rotated so as to bring the part 17 in contact with the inserted and glued cut ends, and so as to heat said glue so as to accelerate the curing or hardening of the glue (Figure 4E) After said curing or hardening the portion of the carrier 9 under the glued cut ends of the wood veneer strips is unbent and the pressure bar 8 is rotated (Figure 4F). A moving table 6 is used to push the cut ends towards one another. This table 6 comprises:

- A first movable support plate 30 with a clamping means 31 to hold a first veneer strip BFl,

- A second movable support plate 32 with a clamping means 33 to hold a second veneer strip BF2, and - A mechanism 34 to simultaneously move the support plates 30, 32 towards one another.

The mechanism 34 (figures 7 and 8) comprises advantageously:

- An eccentric 35 which is mounted and rotatable with respect to the table (vertical axis V)

- An arm 36 that extends between the eccentric 35 and the support plate 30.

- An arm 37 that extends between the eccentric 35 and the support plate 32.

- Ball bearings 38 whereby the ends of the rods are rotatable with respect the eccentric 35 and the support plate 30, 32 (axes of rotation Vl, V2, V3, V4), and - A finger 39 to connect the eccentric to the rod 40 of a cylinder (using a ball bearing 38 between the finger 39 and the rod 40).

The eccentric 35 is preferably located below the machine, while the drive cylinder of the eccentric is preferably along a side of the machine.

By exerting a force on the finger 39, the eccentric 35 turns around its axis of rotation V, such that a tensile force or pushing force is exerted on the support plates. By the rotation of the eccentric 35, the support plates are moved simultaneously towards one another or away from one another. The gluing unit has two cutting units with cutting dies 3, 5. These cutting units can operate simultaneously or otherwise.

The cutting unit 2 or 4 comprises: - A basic element 50 in the form of a frame with a bottom plate 51 , a top plate 52 and side elements 53, 54.

- A lower block 55 that is fixed with respect to the basic element 50 and which carries a first component 56 (the die plate) of the cutting die 3 or 5, whereby this first component or die plate 56 of the cutting die has a top support surface 57, as well teeth located next to one another 58.

- A removal plate 59 with a lower support surface 60.

- A mechanism 61 for making the removal plate 59 move between a first position in which the support surface 60 is in the vicinity of the support surface 57 in order to hold a part of the wood veneer strip when cutting the end, and a second position in which the support surface 60 is removed from the support surface 57, whereby the wood veneer strip is no longer held between these surfaces 57, 60.

- Springs 62ter and guides 62 to control the vertical movement of the removal plate, such that the support surface 60 is parallel to the support surface 57, even with narrow wood veneer strips. - A second component or stamp 63 of the cutting die 3, 5, that is pushed downwards by the mechanism 61 and by a cylinder 64, in order to cut the end.

- An intermediate block 65 that is fixed with the basic element 50, with passages to guide the rods 66.

- A top bar 67 that is moveable with respect to the basic element 50 by the mechanism 61.

A relative movement between the removal plate and the stamp can be obtained by the action of the cylinder 64, which is advantageous for withdrawing the cut strip. In an embodiment, there is only one cutting unit 2 or 4 as described above with a removal plate, while the other cutting unit primarily consists of a die plate and a stamp (and no removal plate 59).

The guides 62 each have a head 62bis that moves in a channel 67 bis of the top bar 67 against the action of the springs 62ter.

These springs Glter preferably exert a pushing force between the removal plate 63 and the top bar 67.

The second component or stamp 63 of the cutting die has teeth that can be moved in the notches between the teeth 58 of the first component or die plate 56 of the cutting die, and in notches between the teeth of the removal plate 59.

The die plate 56 and the stamp 63 have a tooth profile in order to cut the end of a wood veneer strip in the shape of a series of sharp teeth located next to one another, with notches between the teeth.

The removal plate 59 is always under pressure with respect to the top plate 52. This pressure is distributed by a series of springs 72 in order to obtain parallel pressures of the removal plate. The springs 72 are distributed over a length of the top bar, for example over a length of 80cm to 150cm. On the other part of the top bar 67, there are cylinders 73 and/or springs such that the position of the top bar 67 can be adjusted with respect to the top plate 52.

According to an embodiment the top bar has a number of series of springs and/or cylinders, for example a first series of springs 72 A along a first part of the bar, a second series of springs 72B along a second part of the bar, and a third series of springs and/or cylinders 73 along a third part of the bar.

In this way it is possible to make the bar 67 descend in parallel, even if only a part of the width of the removal plate and the stamp is used. The correct descent of the bar can be obtained by controlling the pushing force of the cylinders 73. If the stamp is used for the simultaneous cutting of the ends or sides of a number of wood veneer strips, the cylinders are in operation, whereby the same pressure is exerted on each wood veneer strip. By using the cylinders a good pressure balance can be obtained.

The action of the cylinders 73 can be controlled by a computer.

In an additional embodiment, the springs and cylinders work along the entire length of the top bar, such that each cylinder is driven out separately.

The mechanism 61 (for example a cylinder) acts such that the stamp 63 descends, and the removal plate 59 descends with it.

The relative position of the removal plate 59 with respect to the top bar 67, and thus with respect to the stamp, can be controlled by changing the position of the head along the rod 62.

The end of a wood veneer trip is cut as follows:

In a first step the top bar 67 is moved downwards (B) by the mechanism 61, such that the stamp 63 and the removal plate 59 descend to the die plate 56 (Figure 10A). In this position the springs 62ter exert a pushing force on the removal plate 59, such that the head 62bis of the rod 62 rests against the bottom of the channel 67bis in order to limit the maximum distance between the top bar 67 and the removal plate.

The stamp 63 touches the wood veneer strip, before the removal plate touches the strip, (figure 1 OB - in this position the distance between the removal plate and the top plate is still a maximum). At least the start of the cutting of the end his thus done without the wood veneer strip being tensioned between the die plate 56 and the removal plate 59. This is advantageous as there are fewer small bands in the stamp that cause rubbing, and as cleaner end points are obtained for the cut end.

After the stamp is in the die plate 56 sufficiently, the removal plate 59 can touch the wood veneer strip. (Figure 10C).

If the stamp 63 moves further downwards, the removal plate will be pushed further against the wood veneer strip, such that the springs 62ter are further tensioned. The heads of the rods 62 will be moved upwards in the channels 67 bis.

The waste AF from cutting the end is pushed downwards to fall into a container C (a container that is at least partially under the die plate 56). (figure 10C)

When the main cylinder 61 pulls the top bar upwards, the stamp 63 and the removal plate 59 move upwards (Figure 10D). The cut wood veneer strip is then raised slightly before the removal plate 59 pushes on it (figure 10E), such that the cut wood veneer strip is no longer attached to the stamp 63.

Through the further action of the main cylinder 61 , the stamp 63 is moved further upwards, as is the removal plate 59.

The stamp 63 and the removal plate 59 are then in the position shown in figure 1OA.

To correctly control the gluing unit and the cutting dies, a number of cameras or webcams or optical lenses (100) are provided for taking various images of the wood veneer strips to be glued together, the cutting dies, the carrier for the glue strip, the glue strip deposited on the carrier, etc. These cameras, webcams or optical lenses send these images to control screens (101) whereby an operator can visually control different steps, but also to a computer 102 in which these images are processed to compare one or more parameters of them to reference parameters. If the difference between a parameter of an image and/or a number of images and the reference parameter is greater than a certain percentage, the computer sends an alarm signal. Preferably the computer processes the difference between the parameter(s) and the reference parameter(s) to send signal (s) to control elements of the components of the unit in order to at least partially correct the difference, and/or in case of detection of not suitable glue strip, to prevent the movement of the cut ends of the wood veneer strips the one towards the other and the moving of the carrier so as to place a new glue strip between the cut ends to be glued together. Especially for viewing the glue strip before the movement of the cut ends the one towards to the others (for inserting teeth of one end into notches of the other end, and inversely), the camera(s) or webcam(s) or optical lens(es) will be appropriate for taking enlarged views (for example with an enlargement factor of 10 to 100).

A computer 102 can also be used as an ordinary vision system with a series of small cameras for detecting different places of the machine/wood veneer strips. These small cameras then place different parts of the machine/wood veneer strip on a split screen (for example divided into 4, 6, 8 etc), preferably in black-and-white combination.

The cameras of the vision system send data to the screen. The black-and-white combination of the images can be processed in the cameras, in the vision system, in the computer, etc.

The vision system according to the invention can also be used for other gluing applications, for example in machines for gluing wood veneer strips lengthways.

The cameras can preferably be controlled separately, to zoom in/out separately. The pressure bar as illustrated in one of the figures 4, 13, 14 and 15 can be used for gluing along the length and/or the width of the wood veneer strips, with or without intermediate plates and/or elements, for example for manufacturing parquet, marquetry, etc. The pressure bar is preferably connected to a gluing apparatus, preferably a gluing apparatus with a carrier 9 for a glue strip, in which the carrier is bendable as illustrated in Figures 4A to 4F inclusive.

The cassette with gluing apparatus and pressure bar is preferably detachable with respect to the machine with tables for the wood veneer strips that have to be glued together, and/or with cutting die(s).

The pressure bar is intended to push the ends of the wood veneer strips on the carrier 9, such that the glued ends of the wood veneer strips are pushed together.

Various machines and processes will now be described, in which the gluing of two ends is done by a pressure bar according to the invention.

A. Process in which wood veneer strips are inserted breadthways, (see figure 16)

The longitudinal sides that have to be glued together are cut.

Glue is applied to at least one cut side of a wood veneer strip, for example by means of an adhesive roller, adhesive brush, spray gun, etc. Preferably glue is applied to the two cut sides.

The wood veneer strips are moved together, such that the cut sides are next to one another.

By using heat and a pressure bar according to the invention, the wood veneer strips are glued together breadthways with a pushing force from a longitudinal side of a wood veneer strip to the longitudinal side of the other wood veneer strip. The wood veneer strips glued together form a wider strip that can subsequently be glued to another wider strip in order to obtain a wider wood veneer roll.

The machine also contains cutting systems to cut the lateral ends of the wider strips that have to be glued together, system(s) to apply glue to at least one cut lateral end, and a system to press the cut ends together, preferably by means of a pressure bar according to the invention.

The machine also preferably contains a heating system to accelerate the setting of the glue.

B. Process and machine for gluing wood veneer strips breadthways, (see figure 17)

The opposite longitudinal sides of the strips that have to be glued together are cut.

Glue is applied to at least one cut side of a wood veneer strip, for example by means of an adhesive roller, adhesive brush, spray gun, etc. Preferably glue is applied to the two cut sides.

The wood veneer strips are moved together, such that the cut sides are next to one another.

By using heat and a pressure bar according to the invention, the wood veneer strips are glued together breadthways with a pushing force from a longitudinal side of a wood veneer strip on the longitudinal side of the other wood veneer strip.

The wood veneer strips glued together form a sheet of strips.

The longitudinal end of the sheet of strips that is opposite the longitudinal end of a new wood veneer strip are cut, glued and pressed as described above. The two longitudinal ends of each wood veneer strip may also be cut in parallel before gluing the two wood veneer strips together.

The table can be fitted with stops to correctly position the new wood veneer strip before gluing it to another wood veneer strip.

The table preferably has a means to correctly position the free longitudinal end of the sheet of strips with respect to the stop and/or the pressure bar, in which the correct positioning of this free longitudinal end is determined by means of one or more photocells. By using such a positioning system (e.g. guillotines or guides) the problem of the inserted sheets being crooked can be reduced/avoided.