PIANI DANIELE (IT)
PIANI ALBERTO (IT)
PIANI DANIELE (IT)
| US4070767A | 1978-01-31 | |||
| US5429475A | 1995-07-04 | |||
| US5295309A | 1994-03-22 |
| 1. | A method for levelling and/or turning one or more stacks of sheet material arranged on a base or pallet, characterised in that: to raise the base and hold the stack together while it is levelled and/or turned, a pair of forks is used, operating opposite one another, on the bottom of the base and from above on the top of the stack, said forks belonging to a mobile independent unit which moves the stack and relative base from a first location to a second location, at a distance from the first; to turn the stack, the forks are moved in such a way that they transfer the stack, in several stages, from a vertical position to a horizontal position, in which the stack rests on a first side and can be rotated through 180Q, or a smaller angle, about a vertical axis, then return it to the starting position, or move it to a vertical position turned through 1802 relative to the starting position ; levelling of the stack of sheet material is effected following the first 90g rotation and by means of the temporary angling of the plane upon which the stack lies along a horizontal axis, temporarily resting it with its second side, adjacent to the first side, on a vibrating plate, said plate being part of the mobile independent unit; at least during the stage in which the stack stops in said position resting on the vibrating plate, air jets are blown towards the stack, in a direction substantially concordant with the direction of the planes upon which the sheets that constitute the stack lie; thus, the combined action of the vibrating plate and air jets promotes the reciprocal alignment, or levelling, of the sheets in the stack, one side of the sheets resting on the vibrating plate and a second side, consecutive to the first, resting on a stop formed by the means which directly support the forks. |
| 2. | The method for levelling and/or turning one or more stacks of sheet material according to claim 1, characterised in that said 1804 rotation is effected in two successive stages, each involving a 90Q rotation, being separated by the stage for levelling the stack by the combined action of the vibrating plate and air jets. |
| 3. | The method for turning one or more stacks of sheet material according to claim 1, characterised in that said mobile independent unit is a motordriven carriage which moves on wheels, having a guide device for its movements from a first location to a second location, the latter being at a distance from the former. |
| 4. | A mobile independent unit for levelling and/or turning one or more stacks of sheet material arranged on a base or pallet, and for implementing the method according to claims 1 to 3, characterised in that it comprises: a motordriven carriage which moves on wheels, having a guide device for its movements; a pair of forks for picking up the stack and base, said forks being positioned opposite one another, so that they operate at the bottom of the base and the top of the stack; a vibrating plate, being positioned at the side of and between the forks, on a plane normal to the support planes provided by the forks and being outside the space delimited by said forks; said forks being supported in a bracketlike fashion by a first frame, it being possible to move them towards and/or away from one another; said vibrating plate being supported in a bracketlike fashion by said first frame and projecting from the same part of the carriage as the forks; the centre of said first frame being hinged to a second frame and being fitted with nozzles which are connected to a compressed air source; the centre of said second frame being hinged to the carriage supporting structure, on a horizontal axis transversal to said carriage, the axis being positioned above the top of the carriage itself. |
| 5. | The independent unit according to claim 4, characterised in that devices are envisaged for rotating the second frame in both directions relative to the carriage about said horizontal axis, said devices being located between the second frame and the carriage supporting structure and connected to them; said devices being designed to bring the second frame and, as a result, the first, from a vertical position, with the forks horizontal, to a horizontal position, in which all parts are above the top of the carriage, with the forks vertical, then again to the previous vertical position; it being possible to control said devices in such a way as to allow the temporary stable positioning of the second frame and, as a result, all parts, in an intermediate position between said vertical position and the horizontal position. |
| 6. | The independent unit according to claim 4, characterised in that the first frame is hinged to the second frame in such a way that it can be rotated through 180° relative to the latter; and characterised in that means which can be engaged and disengaged are envisaged for stably connecting the first and second frames to one another: in a first position, in which the first and second frames are completely overlapping; in a second position, in which the first frame overlaps the second to form a crossshape, following a first 90g rotation relative to the first position; a third position, in which the first and second frames are again completely overlapping, following a second 90g rotation of the first frame relative to the first position and in the same direction as the first rotation; thus, upon completion of the second rotation of the first frame relative to the second, the position of the forks is inverted relative to their position with the first and second frames in the abovementioned first position. |
| 7. | The independent unit according to claim 4, characterised in that the axis on which the second frame is hinged to the carriage supporting structure is on a vertical plane, said plane being normal to the plane delimited by the points at which the carriage rests on the floor, said vertical plane passing inside the plane delimited by the points at which the carriage rests on the floor. |
| 8. | The independent unit according to claim 7, characterised in that the barycentre of the carriage is on the vertical plane. |
| 9. | The independent unit according to claim 4, characterised in that the vibrating plate is supported by the first frame by means of a third frame, the latter being attached to the first frame in such a way that it can be moved in a direction transversal to the first frame; said third frame being subject to the action of actuating devices which allow the lateral position of the plate to be adjusted relative to the forks. |
Background Art In the technical sector to which the present invention refers, the term stack of sheet material refers to one or more stacks of sheets made of paper, plastic, laminate or other materials, or one or more stacks of groups of paper, plastic, laminate or other materials suitably arranged in reams.
The technical sector already comprises fixed installation apparatus for levelling and/or turning stacks of sheet material, for example, stacks of sheets made of paper, card or similar materials.
Such apparatus must be supplied with materials and unloaded, using means of transport to transfer the stacks from one location to another, which must carry the stacks to a holding station where the apparatus is installed.
Disclosure of the Invention The main aim of the present invention is to level the sheets or layers of a stack, or to level and turn the stacks (one or more) arranged on a pallet, by means of an independent unit and with operating stages that allow the sheets in the stack to be
straightened up with reference to at least two stops, making contact with two adjacent sides of the stack, making use of the simultaneous action of a vibrating plate and air jets directed in such a way that they cross the stack of material to be levelled and/or turned.
Another aim of the present invention is to provide an independent unit for the implementation of the method disclosed, by means of which the stacks of sheet material, arranged on a pallet, can be moved from one location to another using, for their movement, picking up and setting down, the same means which pick up and support the stacks so as to allow them to be levelled and/or turned.
In a preferred embodiment, the turning of the stacks (one or more) arranged on a pallet, according to the method disclosed in the present invention, is effected by means of a pair of opposite forks, for raising the base and holding the stack together as it is turned, supported, in bracket-like fashion, by a first frame whose central section is hinged to a second frame, the top of which is hinged to a supporting structure which is part of a mobile independent unit, consisting of a motor-driven carriage and equipped with a guide device.
The second frame can rotate from a first position, in which the stack is vertical, to a second position, in which the stack is horizontal and on a plane above the top part of the carriage structure.
With the second frame in this second (horizontal) position, the first frame, and so also the stack, can be rotated through 18011 relative to the second frame, about a vertical axis. Said 180g rotation occurs in two 90g stages, separated by a rotation of the second frame relative to the mobile unit supporting structure, passing from said horizontal position to a temporary intermediate angled position between the second position and the first position, in which the stack is positioned as follows: with one side resting on a vibrating plate, supported by the first frame and located between and to the side of the opposite grippers on a plane outside the space that they delimit;
and crossed by air jets blown from nozzles supported by said first frame.
This promotes alignment of the individual sheets in the stack with one side resting on the vibrating plate and another side, adjacent to the first, resting on the first frame.
Following said first 90i rotation the stack may be returned to its initial position, or may be rotated through a further 90g to turn over the stack, this operation being completed by subsequently bringing the second frame to the first position in which the forks, inverted relative to the starting position, can release the stack.
The method and independent unit disclosed by the present invention are advantageous in achieving the aim of levelling and/or turning stacks of sheet material, arranged on a base (pallet) at the location of the base, with the possibility, if necessary, of moving the base from one location to another, for this transfer using the same operating unit which allows the stack to be turned.
A further advantage of the method and independent unit disclosed in the present invention is the fact that the combined action of the vibrating plate and the nozzles which blow air across the stack of sheet material allows a rapid alignment (or correct levelling) of the sheets in the stack relative to two adjacent references; this facilitates the subsequent correct pick up of individual sheets by pick up means designed, for example, to feed them, individually and automatically, at the desired rates, to subsequent processing lines.
The method and independent unit disclosed in the present invention are described in more detail with reference to the accompanying drawings, the independent unit described according to a preferred, schematic embodiment, without limiting the scope of its application, and in which: Figures 1 to 7 are schematic views of the subsequent stages of turning a stack of sheet material according to the present invention.
Figure 1 illustrates the starting condition valid for both the simple levelling of the sheet material in the stack, or the levelling and subsequent turning of the stack.
In Figure 1, the numeral 1 indicates as a whole the independent unit disclosed by the present invention, comprising a motor-driven carriage, which moves on wheels 2 and is equipped with a guide device 3 for its movements on the floor P3.
The carriage 1 is fitted with a pair of forks 4-4', mounted in bracket-like fashion on a first frame 5. The forks 4-4'can be mounted on the frame 5 using conventional methods known to experts in the trade, and can be moved towards and/or away from one another depending on the size of the stack P of sheet material to be handled.
The centre of the first frame 5 is hinged, by means of a thrust bearing 6a and on an axis 6, to a second frame 7 positioned between the first frame 5 and the supporting structure of the carriage 1.
The first frame 5 and second frame 7 are connected to one another in such a way that the former cannot normally rotate relative to the latter. This connection is made in such a way that it can be temporarily disengaged and, by means of the thrust bearing 6a, the first frame 5 can assume the following positions relative to the second frame 7: a first position, in which the first frame and second frame are completely overlapping; a second position, in which the first frame overlaps the second frame to form a cross shape, following a 90g rotation relative to the first position; a third position, in which the first and second frames are again completely overlapping, following a second 9011 rotation of the first frame relative to the first position and in the same direction as the first rotation.
Obviously, after each 90Q rotation, the first frame 5 can be returned to the starting position and the connection between said first frame and the second frame 7, which prevents their reciprocal rotation, can be restored by the operator.
The second frame 7 is hinged at the top of said carriage 1 supporting structure, about an axis 8 and is connected to one end of a hydraulic piston 14 whose cylinder is attached at the base of the carriage 1 supporting structure.
The numeral 10 is used to label a vibrating plate which, by means of a third frame, comprising"L"-shaped bars 11-12 and guides 15 for the extension 12 of said bars, is attached to the first frame 5. The vibrating plate 10 is positioned between the forks 4-4'and outside the space delimited by the forks. The stable position of the vibrating plate 10 relative to the forks 4 -4'can be adjusted by hydraulic pistons (or other means known to experts in the trade), not illustrated in the accompanying drawings, with one side connected to the bars 11 and the other side connected to the first frame 5, which allow the bars 12 to slide relative to the guides 15, in both directions. The position of the vibrating plate 10 is adjusted according to the size of the stack of sheet material to be handled.
The centre and entire length of the first frame 5 is fitted with at least one set of nozzles (not illustrated in the accompanying drawings), connected to a compressed air source supported by the control unit of the carriage 1; the nozzles are angled in such a way that they can blow air towards the stack P held between the forks 4-4'.
The above is a description of the main parts of the independent unit disclosed. Below is a description of the stages for the two functions relative to the method disclosed in the present invention.
It should be noticed that if the sheet material in the stack P is to be levelled only, the stack will be arranged on a base (or pallet) P1 which will be picked up by the forks 4. If the stack P is also to be turned, a second base P2 must also be envisaged at the top of the stack P and will be picked up by the forks 4'.
With the stack P in the vertical position illustrated in Figure 1, when the hydraulic piston 14 is activated, it causes the rotation (anti-clockwise relative to Figure 1) of the second frame 7-first frame 5-vibrating plate 10 assembly, and-obviously- the stack P, about the axis 8 on which the second frame 7 is
hinged to the carriage 1 supporting structure, until the stack P is horizontal, with a first side resting on the first frame 5 and with all of the relative pick up and supporting apparatus positioned above the top of the carriage 1, as illustrated in Figure 2.
Using the thrust bearing 6a, the operator disengages the connection which normally prevents rotation of the first frame 5 relative to the second frame 7, and rotates said first frame 5 through 90g relative to the second frame 7 (anti-clockwise relative to Figure 2). Upon completion of this rotation, the connection which prevents rotation between the first frame 5 and second frame 7 is restored and the vibrating plate 10 is in a position parallel with the axis 8 on which the second frame 7 is hinged to the carriage 1 supporting structure (see Figure 3).
At this point, the stage in which the sheet material in the stack P is levelled begins. The hydraulic piston 14 receives a command which recalls the piston into the cylinder, bringing the stack P into a position in which it is angled relative to the previous horizontal position, and its second side, adjacent to the side resting on the frame 5 substantially rests on the vibrating plate 10 (see Figure 4).
With the stack P stopped in this position, the vibrating plate 10 is activated for a time which is preset or can be programmed by the operator, and the nozzles are connected to the compressed air source in the carriage 1 control unit.
Thus, the sheet material in the stack P is mechanically levelled relative to the vibrating plate 10 and the resting surface provided by the first frame 5.
Upon completion of this levelling stage, the connection between the nozzles and the compressed air source is interrupted, the vibrator to which the vibrating plate 10 is connected is switched off and the piston 14 is activated in the opposite direction to that previously used, returning the stack P to the horizontal position, as illustrated in Figure 5.
If only levelling of the sheet material in the stack P is required, when the connection which normally prevents rotation of the first frame 5 relative to the second frame 7 has been
disengaged, the first frame 5 is brought to the position illustrated in Figure 2, then the entire apparatus is brought to the starting position illustrated in Figure 1; in this position, the stack P can be unloaded on the spot or, by starting up the drive means and carriage 1 guide, transferred to the stores or to an operating unit for further processing of the sheet material in the stack P.
In contrast, if in addition to levelling of the sheet material in the stack P, said stack P must also be turned, the operator disengages the connection which normally prevents rotation of the first frame 5 relative to the second frame 7 and turns the first frame 5 through a further 90g relative to the second frame 7 and about the axis 6 until the stack P is in the position illustrated in Figure 6, in which the vibrating plate 10 is not visible since, in this condition, it is on the opposite side of the stack P.
At this point, by operating the piston 14, the stack P is moved from the horizontal position to a vertical position, in which it is turned over relative to the starting vertical position, as illustrated in Figure 7, where the forks 4'support the stack from below, whilst the forks 4 hold the top of the stack P.
Upon completion of this turning stage, the stack P can be released on the spot or, by means of the carriage 1, transferred to the stores or to an operating unit for subsequent processing of the sheet material in the stack P.
According to the accompanying drawings and for optimum equilibrium of the independent unit disclosed, the axis 8 on which the second frame 7 is hinged to the carriage 1 supporting structure is on a plane V which lies inside the carriage 1 support plane, delimited by the wheels 2. The barycentre of the independent unit disclosed in preferably on said plane V.
The above description clearly shows that the Applicant has achieved the above-mentioned objects with the invention disclosed.
The present invention may be subject to numerous modifications and variations, all encompassed by the original design concept.
Moreover, all components may be replaced with technically equivalent parts.