Patent Description:
A known automatically-guided vehicle provided with forks comprises: a vertical framework; a carriage which is vertically movable along the vertical framework; and a first fork and a second fork which are borne by the carriage.

A known support structure of tiles comprises: a plurality of uprights (usually four in number), each of which is provided with a first coupling profile at a relative first end and a second coupling profile at a relative second end, opposite the relative first end; a loading plane for receiving the tiles, which is interposed between the first coupling profile and the second coupling profile of each upright of the plurality of uprights.

In order to raise a support structure of tiles, the automatically-guided vehicle positions in such a way that the forks contact the lower surface of the loading plane; thereafter the carriage for raising the forks is activated. At this point, the automatically-guided vehicle can move the support structure of tiles and release them where required, activating the carriage to lower the forks.

In particular, to stack a support structure of tiles on a second support structure of tiles, which for example is at the top of a stack of support structures of pre-existing tiles, it is necessary for the first coupling profile of each upright of the first support structure of tiles to couple to the second coupling profile of each upright of the second support structure of tiles.

This operation is carried out at height (even up to <NUM>-<NUM> metres, in consideration of the height of the store, where the support structures of the tiles are located, and the height of the pre-existing stack) and with the first support structure loaded with tiles.

The weight of the first support structure of tiles and the tiles loaded thereon determines a flexion of the vertical framework which is greater in proportion with the height of the first support structure of tiles to be loaded on the stack: therefore, the vertical framework is inclined forwards (that is, towards the first support structure of tiles) by an angle with respect to a vertical plane. As a consequence, the forks also incline downwards by an angle with respect to a horizontal plane, due to the fact that they are borne by the vertical framework via the carriage. Further, the forks further incline downwards with respect to the horizontal plane, due to the flexion to which the forks are subject due to the weight that they have to bear.

Therefore, at the time of stacking the first support structure of tiles is not horizontal but inclined downwards by an angle, which could prevent the coupling of the first coupling profile of each upright of the first support structure of tiles couples to the second coupling profile of each upright of the second support structure of tiles, which is at the top of the stack.

Consequently, the first support structure of tiles and the tiles loaded thereon might fall: the first support structure of tiles and the tiles loaded thereon can therefore be damaged. Further, the falling of the first support structure of tiles might strike and damage one or more support structures of tiles of the pre-existing stack and/or the automatically-guided vehicle itself. The damage, as can be imagined, might be of a very great extent.

The features of the preamble of claim <NUM> are known from <CIT>, which discloses a method and system for automatically loading and unloading a transport. A guidance system follows a travel path to a position near the transport and then a sensor profiles a transport so that a transport path is determined for an AGV to follow into the transport to place a load and for exiting the transport upon placement of the load.

<CIT> discloses a forklift comprising: tilt sensors mounted on the prongs; a computer which calculates the tilt angles of the prongs, based on the output signals from the sensors; a driving device which receives the output signals from the computer and brings the prongs into the horizontal.

The aim of the present invention consists in obviating the above-mentioned drawbacks.

The above-described aim is obtained with an automatically-guided vehicle provided with forks for moving a support structure of tiles according to claim <NUM>, and with a method for moving a support structure of tiles according to claim.

When the automatically-guided vehicle lifts, by means of the forks, a support structure of tiles loaded with tiles, the first fork and the second fork flex downwards and incline by an angle with respect to the horizontal plane, as explained in the foregoing.

The first sensor detects the inclination and communicates it to the control unit. The control unit can command the actuator means to move the first fork and the second fork up until the inclination of the first fork and the second fork with respect to the horizontal plane is lower than a first angle of tolerance.

It is thus possible to contain the inclination of the first fork and the second fork within the first angle of tolerance, regardless of the weight that the first fork and the second fork have to support and the height at which the forks are situated.

This advantageously makes the stacking operation of a support structure of tiles on a pre-existing stack of other support structures of tiles more secure.

Specific embodiments of the invention will be described in the following part of the present description, according to what is set down in the claims and with the aid of the accompanying tables of drawings, in which:.

With reference to the appended tables of drawings, reference numeral (<NUM>) denotes in its entirety an automatically-guided vehicle provided with forks for
moving a support structure of tiles, comprising: a vertical framework (<NUM>); a carriage (<NUM>) which is vertically movable along the vertical framework (<NUM>); a first fork (<NUM>) and a second fork (<NUM>) which are borne by the carriage (<NUM>); a first sensor (<NUM>) that is mounted on board the first fork (<NUM>) or the second fork (<NUM>), for respectively detecting an inclination of the first fork (<NUM>) or the second fork (<NUM>) with respect to a horizontal plane (xy) (<FIG> illustrate the outline of this plane); a control unit (<NUM>) which is connected to the first sensor (<NUM>); actuator means (<NUM>) which are arranged so as to move the first fork (<NUM>) and the second fork (<NUM>) in order to correct the inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy). The control unit (<NUM>) (<FIG>) is connected to the actuator means (<NUM>) and is configured for commanding the actuator means (<NUM>) as a function of the signal received from the first sensor (<NUM>).

The vertical framework (<NUM>) can comprise a pair of uprights (<NUM>) superiorly connected by a cross-member (<NUM>) to form a frame. In this case the carriage (<NUM>), can be coupled to the vertical framework (<NUM>) in order to slide along the pair of uprights (<NUM>).

The first fork (<NUM>) and the second fork (<NUM>) share, substantially in equal parts, the weight of a support structure di tiles (<NUM>) to be lifted. Therefore, the forks are stressed equally and the first sensor (<NUM>) can be arranged either on the first fork (<NUM>) or the second fork (<NUM>).

The first sensor (<NUM>) is preferably a first horizontal inclinometer.

The first fork (<NUM>) or the second fork (<NUM>) preferably comprises a first housing (<NUM>) (<FIG>) to receive the first horizontal inclinometer. The first housing (<NUM>) can be an undercut fashioned on the upper part of the first fork (<NUM>) or of the second fork (<NUM>).

The automatically-guided vehicle (<NUM>) can comprise a third sensor, for example a second horizontal inclinometer, which is mounted on board the second fork (<NUM>) to detect the inclination of the second fork (<NUM>) (embodiment not illustrated); the first sensor (<NUM>), for example the first horizontal inclinometer, is mounted on-board the first fork (<NUM>) in order to detect the inclination of the first fork (<NUM>).

The third sensor can be connected to the control unit (<NUM>) and the control unit (<NUM>) can be configured for commanding the actuator means (<NUM>) as a function of the signal received from the first sensor (<NUM>) and from the third sensor. The second fork (<NUM>) can comprise a second housing (not illustrated) in order to receive the second horizontal inclinometer; the second housing can be an undercut fashioned on the upper part of the second fork (<NUM>).

The automatically-guided vehicle (<NUM>) comprises a frame (<NUM>).

The automatically-guided vehicle (<NUM>) can comprise a main body (<NUM>).

The automatically-guided vehicle (<NUM>) can comprise a horizontal frame (<NUM>) which projects from the main body (<NUM>).

The horizontal frame (<NUM>) can have a substantially planar shape, in the sense that the relative thickness can be much smaller (at least five times, preferably at least ten times smaller) than the width and length of the horizontal frame (<NUM>).

The horizontal frame (<NUM>) can project from the lower portion of the main body (<NUM>), and is distant from the flooring, for example between five and thirty centimetres from the floor surface.

The horizontal frame (<NUM>) can in turn comprise a first arm (<NUM>) and a second arm (<NUM>) which are flanked to one another and which are flanked to the first fork (<NUM>) and the second fork (<NUM>), and a first rolling element (<NUM>) and a second rolling element (<NUM>) which are borne respectively by the first arm (<NUM>) and by the second arm (<NUM>). The first fork (<NUM>) and the second fork (<NUM>) can be interposed between the first arm (<NUM>) and the second arm (<NUM>).

In a first embodiment not forming part of the present claimed invention, the first fork (<NUM>) and the second fork (<NUM>) are rotatable with respect to the carriage (<NUM>), while the actuator means (<NUM>) comprise a first actuator (<NUM>) for rotating the first fork (<NUM>) and the second fork (<NUM>) with respect to the carriage (<NUM>).

The first fork (<NUM>) and the second fork (<NUM>) are preferably rotoidally coupled to the carriage (<NUM>) with respect to a first hinge axis (Y1) (<FIG>) that is substantially horizontal.

In a second embodiment not forming part of the present claimed invention, the vertical framework (<NUM>) is rotatable with respect to the frame (<NUM>) (<FIG>) of the automatically-guided vehicle (<NUM>), while the actuator means (<NUM>) comprise a second actuator (<NUM>) for rotating the vertical framework (<NUM>) with respect to the frame (<NUM>). The rotation of the vertical framework (<NUM>) by means of the second actuator (<NUM>) can correct the inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy).

The vertical framework (<NUM>) is preferably rotoidally coupled to the frame (<NUM>) with respect to a second hinge axis (Y2) (see <FIG> once more) which is substantially horizontal.

A third embodiment which forms part of the present claimed invention unites the first embodiment with the second embodiment. Therefore, the vertical framework (<NUM>) is rotatable with respect to the frame (<NUM>) of the automatically-guided vehicle (<NUM>), the first fork (<NUM>) and the second fork (<NUM>) are rotatable with respect to the carriage (<NUM>), the actuator means (<NUM>) comprise a first actuator (<NUM>) for rotating the first fork (<NUM>) and the second fork (<NUM>) with respect to the carriage (<NUM>) and a second actuator (<NUM>) for rotating the vertical framework (<NUM>) with respect to the frame (<NUM>).

The activating of both the first actuator (<NUM>) and the second actuator (<NUM>) has the effect of moving the first fork (<NUM>) and the second fork (<NUM>) in order to correct the inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy).

A further object of the present invention is a method for moving a support structure of tiles (<NUM>), by means of the automatically-guided vehicle (<NUM>) as according to the third embodiment, comprising steps of: raising a support structure of tiles (<NUM>); detecting the inclination of the first fork (<NUM>) or the second fork (<NUM>) with respect to a horizontal plane (xy); if the first fork (<NUM>) or the second fork (<NUM>) is inclined with respect to the horizontal plane (xy) by a greater angle than a first angle of tolerance, moving the first fork (<NUM>) and the second fork (<NUM>) in order to correct the inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy), until the first fork (<NUM>) and the second fork (<NUM>) are inclined with respect to the horizontal plane (xy) by a smaller angle than the first angle of tolerance.

The first angle of tolerance can be of about <NUM> degrees. In a fourth embodiment forming part of the present claimed invention (<FIG>, <FIG>), the automatically-guided vehicle (<NUM>) comprises a second sensor (<NUM>) which is mounted on board the vertical framework (<NUM>) for detecting the inclination of the vertical framework (<NUM>) with respect to a vertical plane (yz) (see the broken lines illustrated in <FIG>). The control unit (<NUM>) is connected to the second sensor (<NUM>).

The second sensor (<NUM>) is preferably a vertical inclinometer.

Again with reference to the fourth embodiment, the vertical framework (<NUM>) is rotatable with respect to the frame (<NUM>) of the automatically-guided vehicle (<NUM>), the first fork (<NUM>) and the second fork (<NUM>) are rotatable with respect to the carriage (<NUM>), the actuator means (<NUM>) comprise a first actuator (<NUM>) for rotating the first fork (<NUM>) and the second fork (<NUM>) with respect to the carriage (<NUM>) and a second actuator (<NUM>) for rotating the vertical framework (<NUM>) with respect to the frame (<NUM>).

A further object of the present invention concerns a method for moving a support structure of tiles (<NUM>), by means of the automatically-guided vehicle (<NUM>) defined in the foregoing with the fourth embodiment, which method comprises, with respect to the method already defined in the foregoing, the step of detecting the inclination of the vertical framework (<NUM>) with respect to a vertical plane (yz). The method further comprises: if the first fork (<NUM>) or the second fork (<NUM>) is inclined with respect to the horizontal plane (xy) by a greater angle than a first angle of tolerance, carrying out following sub-steps:.

The second angle of tolerance can be of about <NUM> degrees.

Sub-step b) is preferably carried out only after sub-step a) has been carried out, if the first fork (<NUM>) and the second fork (<NUM>) are still inclined with respect to the horizontal plane (xy) by a greater angle than the first angle of tolerance.

There follows a description of how the automatically-guided vehicle (<NUM>), according to the fourth embodiment of the present invention, can move a support structure of tiles (<NUM>), initially arranged on a flooring (<FIG>). Refer to figures from <NUM>-<NUM> and 6A.

<FIG> illustrates a first support structure of tiles (<NUM>) positioned on the floor, which is to be raised and arranged on a second support structure of tiles (<NUM>) which is located on the top of a pre-existing stack (<NUM>) of support structures of tiles (see <FIG> for example). Normally each support structure of tiles (<NUM>) is loaded with tiles, which for the sake of simplicity have not been illustrated.

Each support structure of tiles (<NUM>) comprises: a plurality of uprights (<NUM>) (usually four in number), each of which is provided with a first coupling profile (<NUM>) at a relative first end and a second coupling profile (<NUM>) at a relative second end, opposite the relative first end; a loading plane (<NUM>) for receiving the tiles, which is interposed between the first coupling profile (<NUM>) and the second coupling profile (<NUM>) of each upright (<NUM>) of the plurality of uprights.

The automatically-guided vehicle (<NUM>) nears the first support structure of tiles (<NUM>) to be lifted and stacked (see <FIG>), until the horizontal frame (<NUM>) is arranged below the first support structure of tiles (<NUM>). Thereafter, the carriage (<NUM>) is activated by motor means (not illustrated), to lift the forks (<NUM>, <NUM>) and then also the first support structure of tiles (<NUM>) (see <FIG>).

As can be observed in <FIG> (see the broken lines), the weight of the first support structure of tiles (<NUM>) determines an inclination of the vertical framework (<NUM>) with respect to the vertical plane (yz), detected by the second sensor (<NUM>), as well as an inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy), detected by the first sensor (<NUM>).

If the first fork (<NUM>) (on which the first sensor (<NUM>) is fixed, but like considerations are also true if the first sensor (<NUM>) is arranged on the second fork (<NUM>)) is inclined with respect to the horizontal plane (xy) by a greater angle than a first angle of tolerance, the following sub-steps might be carried out:.

Once the above-described method has been carried out, the first fork (<NUM>) and the second fork (<NUM>) are inclined with respect to the horizontal plane (xy) by a smaller angle than the first angle of tolerance.

At this point the automatically-guided vehicle (<NUM>) nears (<FIG>) to the pre-existing stack (<NUM>) until the horizontal frame (<NUM>) is arranged beneath the support structure of tiles of the stack (<NUM>) positioned on the flooring (<FIG>).

Subsequently the carriage (<NUM>) is activated by the motor means to lower the forks (<NUM>, <NUM>) until the first coupling profile (<NUM>) of each upright (<NUM>) of the first support structure of tiles (<NUM>) couples to the second coupling profile (<NUM>) of each upright (<NUM>) of the second support structure of tiles (<NUM>) (<FIG>).

Claim 1:
An automatically-guided vehicle (<NUM>) provided with forks for moving a support structure of tiles (<NUM>), comprising:
a vertical framework (<NUM>);
a carriage (<NUM>) which is vertically movable along the vertical framework (<NUM>);
a first fork (<NUM>) and a second fork (<NUM>) which are borne by the carriage (<NUM>);
a first sensor (<NUM>);
a control unit (<NUM>) which is connected to the first sensor (<NUM>);
actuator means (<NUM>) which are arranged so as to move the first fork (<NUM>) and the second fork (<NUM>) in order to correct the inclination of the first fork (<NUM>) and the second fork (<NUM>) with respect to the horizontal plane (xy);
wherein the control unit (<NUM>) is connected to the actuator means (<NUM>) and is configured for commanding the actuator means (<NUM>) as a function of the signal received from the first sensor (<NUM>);
characterised in that:
the first sensor (<NUM>) is mounted on board the first fork (<NUM>) or the second fork (<NUM>), for respectively detecting an inclination of the first fork (<NUM>) or the second fork (<NUM>) with respect to a horizontal plane (xy);
the first fork (<NUM>) and the second fork (<NUM>) are rotatable with respect to the carriage (<NUM>) and wherein the actuator means (<NUM>) comprise a first actuator (<NUM>) for rotating the first fork (<NUM>) and the second fork (<NUM>) with respect to the carriage (<NUM>);
it comprises a frame (<NUM>), wherein the vertical framework (<NUM>) is rotatable with respect to the frame (<NUM>) and wherein the actuator means (<NUM>) comprise a second actuator (<NUM>) for rotating the vertical framework (<NUM>) with respect to the frame (<NUM>).