Patent Description:
In particular, the invention relates to the structure of an edging machine comprising a gluing unit for applying a glue layer on a surface of a panel (when said surface is subjected to machining by said edging machine), wherein said structure is designed to indirectly determine (i.e. through the thickness of a glue layer on said gluing roller) the thickness of the glue layer on the surface of the panel.

Preferably, the edging machine is designed to verify whether the thickness of the glue layer on the surface of the panel is equal to a desired thickness based on the machining to be carried out on the surface of the panel.

The gluing unit comprises a shutter and a gluing roller and in case of a negative outcome of the verification, it is necessary to rotate the shutter with respect to the gluing roller so that more or less glue is transferred from the shutter to the gluing roller to obtain a thickness of the glue layer on the surface of the panel equal to the desired thickness.

It is known that an edging machine is capable of applying an edging tape to a surface of a panel using a quantity of glue.

For this purpose, the edging machine is provided with a gluing unit.

A gluing unit of a known type comprises a container containing a quantity of glue, a shutter and a gluing roller.

The shutter is connected to the container and has a rotation axis around which said shutter rotates to transfer more or less glue to the gluing roller.

In particular, the shutter comprises a first slot to receive a quantity of glue coming from the container and a second slot, different from the first slot, to transfer said quantity of glue from the shutter to the gluing roller.

A further shutter, placed inside said shutter, allows/prevents the transfer of said quantity of glue towards the shutter roller.

The gluing roller has a rotation axis around which said gluing roller rotates, parallel to the rotation axis of the shutter.

The gluing roller rotates around its rotation axis, so that the quantity of glue coming out of the shutter is distributed on the outer surface of the gluing roller and forms a glue layer.

In fact, during the rotation of the gluing roller, portions of the outer surface of the gluing roller, different from each other, come into contact with the second slot of the shutter, and a respective quantity of glue coming out from the second slot of the shutter reaches each of said portions of outer surface.

A numerically controlled motor is connected to the shutter and configured to rotate the shutter around its rotation axis so that more or less glue flows out of the shutter.

Consequently, the glue layer on the outer surface of the gluing roller can have a greater or lesser thickness based on the quantity of glue flowing out of the shutter.

A logic control unit is connected to the numerically controlled motor and configured to control the numerically controlled motor.

In particular, the logic control unit is configured to control the numerically controlled motor on the basis of a desired value which is a reference value associated with the thickness that a glue layer should have on a surface of a panel depending on the specific machining to be carried out on the surface of the panel.

Consequently, for each machining to be carried out on a surface of a panel, the thickness that the glue layer on said surface of said panel must have is established a priori.

The reference value associated with the thickness that the glue layer should have on the panel surface is stored in a memory before the panel surface is subjected to machining.

For example, if a surface of a panel is to be finished using a first edging tape or a second edging tape, different from the first edging tape, the thickness of the glue layer on the surface of the panel must have a different height based on the edging tape, and the thickness height value is established before the surface of the panel is machined.

Therefore, depending on the machining to be carried out on a surface of a panel, it is necessary that the glue layer on the surface of the panel has a respective predetermined thickness.

A disadvantage of said known type edging machine is given by the fact that it is not possible to determine the thickness of the glue layer on the surface of the panel.

A further disadvantage is given by the fact that, although a reference value associated with the thickness of the glue layer on the surface of the panel is stored and although the logic control unit controls a numerically controlled motor, often, the glue layer on the surface of the panel does not have the correct thickness, i.e. the thickness does not have the desired value for the machining to be carried out on said surface of said panel.

In fact, often, the glue layer on the surface of the panel has a thickness greater or lesser than the thickness desired for the machining to carried out on said surface of said panel.

This is due to various factors and mainly to the following factors: the wear of one or more components of the gluing unit, in particular the components that must perform a movement (such as the gluing roller or the shutter), the type of glue, the viscosity of the glue, and the temperature of the glue.

As regards the wear of the components of the gluing unit, the fact that one or more components of the gluing unit are worn affects the quantity of glue that flows out of the shutter and reaches the gluing roller.

As regards the type of glue, the glue can be a hot-melt glue (whose melting temperature is typically <NUM>), such as an EVA glue ("Ethylene Vinyl Acetate"), or a polyurethane glue (the whose melting temperature is typically <NUM>).

The hot-melt glue is a reversible glue, i.e. a glue that can be heated several times without its chemical-physical characteristics being altered.

Polyurethane glue is a glue having a strength greater than the strength of a hot-melt glue.

As regards viscosity, glue can have a more or less high viscosity value.

The higher the viscosity of the glue, the lower the quantity of glue that reaches the shutter and consequently the gluing roller.

As regards the temperature of the glue, the glue is in a more or less liquid state depending on its temperature.

The higher the temperature of the glue, the greater the quantity of glue that reaches the shutter and consequently the gluing roller.

The factors mentioned above affect the quantity of glue that reaches the gluing roller and consequently the quantity of glue applied to the surface of the panel via said gluing roller.

Therefore, in practice, it is difficult to obtain a thickness of the glue layer on the surface of the panel to be machined which is equal to the thickness desired for machining said surface of said panel.

The aim of the present invention is to overcome said disadvantages by providing an edging machine comprising a gluing unit which in turn comprises a shutter and a gluing roller, in which said edging machine is configured to apply, through said shutter roller, a glue layer on a surface of a panel to be machined and to determine indirectly (i.e. via the glue layer on the gluing roller) the thickness of the glue layer on said surface of said panel.

it is object of the invention an edging machine comprising:.

wherein
said logic control unit is configured to:.

Said gluing unit can comprise a motor for rotating said shutter around its rotation axis with respect to said gluing roller.

In a first alternative, said logic control unit can be configured to:.

Said edging machine can comprise a control panel provided with displaying means for displaying data.

In a second alternative, said logic control unit can be configured to send said signal to said displaying means, wherein said signal contains information relating to the thickness of the glue layer on the outer surface of said gluing roller and/or information relating to said difference value, and said displaying means can be configured to receive said signal.

Said edging machine can comprise alarm means and said logic control unit can be connected to said alarm means.

Regardless of the alternatives mentioned above, said logic control unit can be configured to activate said alarm means when said difference value is different from said reference thickness.

With reference to the gluing roller, said shutter can be configured to rotate around its rotation axis in a first direction and said gluing roller is configured to rotate around its rotation axis in a second direction, opposite to said first direction.

Said gluing unit can comprise a further shutter, arranged inside said shutter, in which said further shutter is movable between a first position, in which said further shutter allows the passage of said quantity of glue from said first slot to said second slot, and a second position, in which said further shutter prevents the passage of said quantity of glue from said first slot to said second slot.

With reference to the motor, said motor is a numerically controlled motor.

With reference to the sensor, said sensor can be a laser sensor, wherein said laser sensor is an image-based laser sensor.

In particular, said sensor can comprise a laser source and a camera and is arranged with respect to the gluing roller so that said laser source emits at least one respective laser beam on one or more points of the glue layer on the outer surface of said gluing roller and that said one or more points of said glue layer fall within a visual field of said camera.

In particular, said sensor can be configured to determine the thickness of said glue layer on the outer surface of said gluing roller by acquiring one or more respective heights associated with said one or more points of said glue layer with respect to the outer surface of said gluing roller and calculating a mean value of said heights.

In an alternative, said sensor can be a distance sensor chosen from the following group of distance sensors: a magnetic distance sensor, an optical distance sensor, an ultrasonic distance sensor, an inductive distance sensor, a capacitive distance sensor, a magneto-inductive distance sensor.

Said gluing unit can comprise a supporting element for supporting said gluing roller and said sensor can be connected to said supporting element through an arm.

The present invention will be now described, for illustrative, but not limitative purposes, according to its embodiment, making particular reference to the enclosed figures, wherein:.

With particular reference to <FIG>, an edging machine <NUM> is disclosed.

The edging machine <NUM> is used to apply an edging tape on a surface S of a panel P.

The panel can be a wooden panel or another material.

In the example being disclosed, the panel P is a wooden panel.

In order to glue an edging tape onto a surface S of the panel P, the edging machine <NUM> is provided with a gluing unit <NUM>.

With particular reference to <FIG>, said gluing unit <NUM> comprises:.

With reference to the shutter <NUM>, said shutter <NUM> has a rotation axis A and comprises a first slot <NUM> to receive said quantity of glue from said container <NUM> and a second slot <NUM> to transfer said quantity of glue to said gluing roller <NUM>, so that a glue layer is formed on the outer surface 5A of said gluing roller <NUM>.

The shutter <NUM> is arranged in such a way that the second slot <NUM> faces a portion of the outer surface 5A of the gluing roller <NUM>.

In particular, the second slot <NUM> can have a portion in contact to the outer surface 5A of the gluing roller <NUM> or be spaced from said outer surface 5A of said gluing roller <NUM>.

In the embodiment being disclosed, the shutter <NUM> is configured to rotate around its rotation axis A in a first direction D1 and said gluing roller <NUM> is configured to rotate around its rotation axis B in a second direction D2, opposite to said first direction D1.

In particular, said gluing unit <NUM> comprises a further shutter <NUM>, arranged inside said shutter <NUM>, in which said further shutter <NUM> is movable between a first position, in which said further shutter <NUM> allows the passage of said quantity of glue from said first slot <NUM> to said second slot <NUM>, and a second position, in which said further shutter <NUM> prevents the passage of said quantity of glue from said first slot <NUM> to said second slot <NUM>.

With reference to the gluing roller <NUM>, said gluing roller <NUM> has a rotation axis B, parallel to the rotation axis A of the shutter <NUM>, so that, when said gluing roller <NUM> rotates, a quantity of glue is applied on a surface S of the panel P and a glue layer is formed on said surface S of said panel P.

In other words, the rotation of the gluing roller <NUM> allows a quantity of glue present on its outer surface 5A to be applied on the surface S of the panel P.

The edging machine <NUM> comprises a sensor <NUM> to determine a thickness of the glue layer on the outer surface 5A of said gluing roller <NUM>.

Said sensor <NUM> is arranged according to the invention, in such a way as to face a portion of the gluing roller <NUM>.

With reference to the sensor <NUM>, in the embodiment being disclosed, said sensor <NUM> is a laser sensor, in particular an image-based laser sensor.

As shown in <FIG>, said sensor <NUM> (i.e. the laser sensor) comprises a laser source <NUM> and a camera <NUM>.

Said sensor <NUM> is arranged with respect to the gluing roller <NUM> so that said laser source <NUM> emits at least one respective laser beam on one or more points of the glue layer on the outer surface 5A of the gluing roller <NUM> and that said one or more points of said glue layer fall within a visual field of said camera <NUM>.

In particular, said sensor <NUM> is configured to determine the thickness of the glue layer on the outer surface 5A of the gluing roller <NUM> by acquiring one or more respective heights associated with said one or more points (of said glue layer with respect to the outer surface 5A of the gluing roller <NUM>) and calculating a mean value of said heights.

In other words, for each of said points of the glue layer the sensor is adapted to acquire a respective height and calculate the mean value of the height values associated with each point.

However, the sensor <NUM> does not need to be a laser sensor.

In an alternative, said sensor can be a distance sensor, without departing from the scope of the invention.

For example, said distance sensor can be chosen from the following group of distance sensors: a magnetic distance sensor, an optical distance sensor, an ultrasonic distance sensor, an inductive distance sensor, a capacitive distance sensor, a magneto-inductive distance sensor.

In the embodiment being disclosed, said gluing unit <NUM> comprises a supporting element <NUM> for supporting at least one gluing roller <NUM> and the sensor <NUM> is connected to said supporting element <NUM> through an arm <NUM>.

In the embodiment being disclosed, said supporting element <NUM> supports said shutter <NUM> and said gluing roller <NUM>.

In particular, an end surface of said shutter <NUM> and an end surface of said gluing roller <NUM> contact a surface of said supporting element <NUM>.

However, although not shown in Figures, it is not necessary that the sensor <NUM> is connected to the gluing unit <NUM>.

The important thing is that the sensor <NUM> is positioned inside the edging machine <NUM> in such a way that a light radiation (in this specific case the laser) emitted by the sensor <NUM> hits the outer surface 5A of the gluing roller <NUM>.

Said edging machine <NUM> further comprises:.

In other words, the logic control unit <NUM> is connected to the sensor <NUM> and acquires two values associated with the thickness of the glue layer present on the outer surface 5A of the gluing roller <NUM> and calculates the difference between said two values.

The result of this difference (i.e. the difference value) is the thickness of the glue layer on the surface S of the panel P.

Consequently, the thickness of the glue layer on the surface S of the panel P is indirectly determined by the thickness of the glue layer present on the outer surface 5A of the gluing roller <NUM>.

Said edging machine <NUM> further comprises storage means <NUM> in which the following data can be stored:
one or more reference thicknesses, each of which is a thickness associated with a respective glue layer to be applied on a surface S of a panel P to be subjected to a respective predetermined machining.

Said storage means <NUM> can comprise a memory.

In the embodiment being disclosed, said storage means <NUM> are external to the logic control unit <NUM>.

However, said storage means <NUM> can be included in said logic control unit <NUM>, without departing from the scope of invention.

Said logic control unit <NUM> can be configured to:.

In a first alternative, said signal can be a control signal to control a motor for rotating the shutter <NUM>.

In fact, the gluing unit <NUM> can comprise a motor <NUM> for rotating the shutter <NUM> around its rotation axis A with respect to the gluing roller <NUM>.

In the embodiment being disclosed, said motor <NUM> is a numerically controlled motor.

The following data can be stored in said storage means <NUM>:.

Each predetermined factor is a value that indicates an increase/reduction of a thickness of a glue layer on said gluing roller <NUM> associated with a respective reference angle.

For example, said value can be a percentage value to express the increase or reduction in the thickness of a glue layer on said gluing roller <NUM> as a function of the reference angle.

Advantageously, through the signal sent to the motor <NUM> of the shutter <NUM>, it is possible to carry out an automatic control of the thickness of the glue layer present on the outer surface 5A of the gluing roller <NUM> so that the thickness of the glue layer on the surface S of the panel P is the thickness required by the specific machining to which said surface S of said panel P is subjected.

In a second alternative, said signal can be a signal containing information relating to one or more thickness values associated with the glue layer present on the outer surface 5A of the gluing roller <NUM> and/or information relating to the aforementioned difference value intended to a control panel <NUM>.

In particular, the edging machine <NUM> can comprise a control panel <NUM> provided with displaying means <NUM> for displaying data and the logic control unit <NUM> can be configured to send said signal to said displaying means <NUM>.

Said displaying means <NUM>, included in said control panel <NUM>, are configured to receive said signal.

In the embodiment being disclosed, said displaying means <NUM> comprise a display.

Advantageously, the values of the thickness of the glue layer on the outer surface 5A of the gluing roller <NUM> and/or the difference value are displayed on said displaying means <NUM> and allow an operator reading such values and/or such difference value to take action/operate through control panel <NUM> on the motor <NUM> of the shutter <NUM> to rotate said shutter <NUM> around its rotation axis A with respect to said gluing roller <NUM> so that the glue layer on said surface S of said panel P increases/decreases until the thickness of said glue layer on said surface S of said panel P is equal to the reference thickness.

Through the control panel <NUM>, the operator can view the data relating to the thickness of the glue layer on the outer surface <NUM> of the gluing roller <NUM> and control the motor <NUM> of the shutter <NUM>.

For example, the operator can select a reference thickness (depending on the machining to which the surface S of the panel P is subjected) on said displaying means <NUM> and through the logic control unit <NUM> send a signal to the motor <NUM> to rotate the shutter <NUM> around its rotation axis A.

Furthermore, regardless of the above-mentioned alternatives, said edging machine <NUM> can comprise alarm means and said logic control unit <NUM> can be connected to said alarm means and configured to activate said alarm means when said difference value is different from said reference thickness.

In particular, said alarm means can comprise a light and/or acoustic source.

In particular, said alarm means can be arranged at any point of the edging machine <NUM>.

For example, said alarm means can be included in the control panel <NUM>.

<FIG> show the gluing unit <NUM> in three different situations.

<FIG> shows a first situation in which a quantity of glue from the container <NUM> has reached the shutter <NUM> but has not been transferred from the shutter <NUM> to the gluing roller <NUM>.

The second slot <NUM> of the shutter <NUM> comprises a first end portion 32A and a second end portion 32B, opposite to said first end portion 32A.

In this first situation, the first end portion 32A contacts the outer surface 5A of the gluing roller <NUM> and the second end portion 32B is spaced from the outer surface 5A of the gluing roller <NUM>.

However, the quantity of glue does not reach the outer surface 5A of the gluing roller <NUM>.

<FIG> shows a second situation in which a quantity of glue has been transferred from the shutter <NUM> to the gluing roller <NUM> but said quantity of glue has not been applied from the gluing roller <NUM> on the surface S of the panel P.

In this second situation, the shutter <NUM> is rotated of a certain angle around its rotation axis A.

Consequently, the shutter <NUM> is rotated with respect to the gluing roller <NUM>.

The first end portion 32A and the second end portion 32B of the second slot <NUM> are spaced from the outer surface 5A of the gluing roller <NUM>, so that a quantity of glue reaches the outer surface 5A of the gluing roller <NUM>.

The sensor <NUM> is in use and a first thickness value of the layer glue on the outer surface 5A of the gluing roller <NUM> is determined.

<FIG> shows a third situation in which said quantity of glue has been applied from the gluing roller <NUM> on a surface S of the panel P.

In this third situation, the gluing roller <NUM> contacts the surface S of the panel P and a quantity of glue is applied on said surface S of said panel P.

The sensor <NUM> is in use and a second thickness value of the glue layer on the outer surface 5A of the gluing roller <NUM> is determined.

Although not said, also in the first situation, the sensor can be in use and a thickness value of the glue layer on the outer surface 5A of the gluing roller <NUM> can be determined.

In this case, the values associated with the glue layer on the outer surface 5A of the gluing roller <NUM> can be a calibration value.

Furthermore, the shutter <NUM> rotates between:.

An advantage is given by the fact that the edging machine <NUM>, object of the present invention, allows not only to apply a glue layer on a surface S of a panel P through a gluing roller <NUM>, but also to indirectly determine the thickness of said glue layer, i.e. through the thickness of a glue layer on the outer surface 5A of the gluing roller <NUM> (by means of which a quantity of glue is applied on the surface S of the panel P and forms a glue layer on said surface S).

A further advantage is given by the fact that said edging machine can be designed to verify whether the thickness of the glue layer on the surface S of the panel P is equal to a desired thickness depending on the machining to which said surface S of said panel P is subjected and to generate a signal which may be a signal sent to the motor <NUM> to rotate the shutter <NUM> with respect to the gluing roller <NUM> or sent to display means <NUM>, included in a control panel <NUM>, so that an operator is aware that it is necessary to rotate the shutter <NUM> with respect to the gluing roller <NUM>.

Claim 1:
Edging machine (<NUM>) comprising:
- a gluing unit (<NUM>) comprising:
a container (<NUM>) containing a quantity of glue,
a shutter (<NUM>) connected to said container (<NUM>),
a gluing roller (<NUM>) comprising an outer surface (5A),
wherein
said shutter (<NUM>) has a rotation axis (A) and comprises a first slot (<NUM>) to receive said quantity of glue from said container (<NUM>) and a second slot (<NUM>) to transfer said quantity of glue to said gluing roller (<NUM>), so that a glue layer is formed on the outer surface (5A) of said gluing roller (<NUM>),
said gluing roller (<NUM>) has a rotation axis (B), parallel to the rotation axis (A) of the shutter (<NUM>), so that, when said gluing roller (<NUM>) rotates, a quantity of glue is applied on a surface (S) of a panel (P) and a glue layer is formed on said surface (S) of said panel (P),
- a sensor (<NUM>) to determine a thickness of said glue layer on the outer surface (5A) of said gluing roller (<NUM>), characterized in that said sensor (<NUM>) being arranged in such a way as to face a portion of the gluing roller (<NUM>), and
- a logic control unit (<NUM>) configured to:
o acquire, through said sensor (<NUM>):
a first thickness value associated with said glue layer on the outer surface (5A) of said gluing roller (<NUM>) in a first time instant, wherein a quantity of glue has been transferred from said shutter (<NUM>) to said outer surface (5A) of said gluing roller (<NUM>), so that a glue layer is formed on said outer surface (5A) of said gluing roller (<NUM>), but said gluing roller (<NUM>) is not in use, so that said quantity of glue is not applied on the surface (S) of the panel (P), and
a second thickness value associated with said glue layer on the outer surface (5A) of said gluing roller (<NUM>) in a second time instant, different from said first time instant, wherein a quantity of glue has been transferred from said shutter (<NUM>) to said outer surface (5A) of said gluing roller (<NUM>), so that a glue layer is formed on said outer surface (5A) of said gluing roller (<NUM>), and said gluing roller (<NUM>) is in use, so that said quantity of glue is applied on the surface (S) of the panel (P) and a glue layer is formed on said surface (S) of said panel (P),
∘ calculate a difference value equal to the difference between said first thickness value and said second thickness value to determine a thickness of a glue layer on said surface (S) of said panel (P).