MACHINE FOR MANUFACTURING CARDBOARD BLANKS
TECHNICAL FIELD
The present invention relates to apparatuses and machines for working packaging cardboard. Particularly, the invention refers to a machine for manufacturing cardboard blanks having different dimensions and shapes using cardboard sheets or webs.
BACKGROUND ART
There are known automatic machines for working cardboard sheets or webs, designed and built for executing a predefined sequence of operations on large batches of cardboard sheets, for instance in mass productions of large amount of blanks of the same type.
Said machines can be adjusted and set for manufacturing any types of blank, but they usually require laborious and complex adjustment and setting operations, which need skilled operators and which involve long stop periods of the machine and thus interruptions of the production.
If items and elements must be manufactured with different and special shapes, in small batches, it is often not convenient to use traditional punch cutter machines, since the different equipping times, which are needed for setting the tools to work the cardboard sheets for the different blanks, would be notably longer than the production real time. In these cases it is preferable to use skilled operators, which manually work the cardboard sheets in order to manufacture the desired blanks.
The main drawback of the above automatic punch cutter machines consists in the low operational flexibility thereof, due to the laborious and complex adjustment and setting operations to set said machines in order to manufacture different types of blanks.
DISCLOSURE OF THE INVENTION
An object of the present invention is to propose a machine for manufacturing cardboard blanks, which is versatile and flexible and capable to manufacture a large range of blanks having different shapes and sizes.
Further object is to propose a machine having a high output, fit to operate with single sheets or continuous sheets module or web of cardboard, minimizing the waste of material and notably reducing the manufacturing times of some type packaging blanks.
Other object is to propose a reliable machine, safe for the operators. The above-mentioned objects are achieved according to the claim content.
BRIEF DESCRIPTION OF THE DRAWINGS
The characteristics of the present invention are underlined in the following, with particular reference to the attached drawings, in which: figure 1 shows a plan schematic view of the machine for manufacturing cardboard blanks of the present invention; - figure 2 shows a rear view of the machine of figure 1, in which some parts have been removed for better underlining others; figure 3 shows a section view according to line III-III of figure 1; figure 4 shows a front and partial view of the machine of figure 1; figure 5 shows a section view according to line V-V of figure 3; - figure 6 shows a cross section view of a variant of the machine of figure 1.
BEST MODE OF CARRYING OUT THE INVENTION
With reference to figures 1 to 5, numeral 1 indicates a machine for manufacturing cardboard blanks from a portion 100 of cardboard sheet, substantially comprising a feeding assembly 2 of the cardboard portion 100, a first working assembly 3 and a second working assembly 5, positioned downstream the first working assembly 3. The cardboard portion 100 can be constituted by a single sheet or a sheet of a continuous module or a piece of a continuous web.
The first working assembly 3 includes a first operating head 4, which is mobile in a transversal direction, nearly orthogonal to the moving direction of the cardboard portion 100 and which is operated by first actuator means 51.
The first operating head 4 includes first cutting means 20 and first creasing means 21 rotatably connected to a rocking first carriage means 24, which is driven by third actuator means 23, between a transversal cut condition A, wherein the first cutting means 20 bear against the cardboard portion 100 in order to execute transversal incisions and the first creasing means 21 are spaced apart from the cardboard portion 100, and a transversal creasing condition B, wherein the first creasing means 21 bear against the cardboard portion 100 in order to execute at least a transversal creasing and the first cutting means 20 are spaced apart from said portion 100.
The first working assembly 3 is provided with first guide means 7, fixed to a frame 49 of the machine 1, for slidably supporting the first operating head 4.
The first operating head 4 is translated by first actuators 51 through first transmission means
13, for instance consisting of an open loop belt, whose ends are connected to said operating head 4.
Alternatively, the first transmission means 13 may include one worm screw whose stem, rotated by first actuators means 51, engages a corresponding nut screw connected to the first operating head 4.
The second working assembly 5 includes a plurality of second operating heads 6, each of which is independently movable by a respective second actuator means 52 in a transversal direction with respect to the machine 1.
Each second operating head 6 is provided with second creasing means 31 and second cutting means 30 or eventually other typologies of tools; the cutting means 30 can be positioned by forth actuator means 33, between a longitudinal cut condition C, wherein they bear against the cardboard portion 100 to execute longitudinal incisions, and a disengagement condition E, wherein the second cutting means 30 are spaced apart from the portion 100. The second creasing means 31 are generally in contact with the cardboard portion 100 in a longitudinal creasing condition D.
The second working assembly 5 is provided with second guide means 8 fixed to the frame 49 of the machine 1 and fit to slidably support the plurality of second operating heads 6. First rack means 14 are fixed to second guide means 8 and second actuator means 52 of echa second operating heads 6 are connected to said rack means 14 by means of respective pinion gears.
The cutting means, first 20 and second 30, of each operating head, first 4 and second 6 respectively, are constituted by a set of circular rotating idle blades or cutters, usually a single disk blade or a couple of side by side blades. Likewise, the creasing means, first 21 and second 31, of each operating head, respectively first 4 and second 6, include a set of rotating idle circular creasing disks, usually consisting of a single or double disk.
The machine further includes fixed support means 22, fit to support the cardboard portion 100 and to abut on first cutting means 20 and first creasing means 21, respectively in a transversal cut condition A and in a transversal creasing condition B. An abutment assembly 9 is provided, constituted by a plurality of abutment heads 10, each of which aligned and opposed to a respective second operating head 6 of the second working assembly 5 and which can be independently driven, by a respective fifth actuator means 53, in a transversal direction with respect to machine 1.
Each abutment head 10 includes abutment means, first 40 and second 41, fit to support the cardboard portion 100 and mostly to bear against, respectively, the second cutting means 30 and the second creasing means 31 of the respective second operating head 6, in the longitudinal cut condition C and in the longitudinal creasing condition D, respectively, in order to execute the corresponding working.
Particularly, each first abutment means 40 is constituted by one or more rotating disks, whose number corresponds to that of the rotating blades of the corresponding second cutting means 30. Each rotating abutment disk is provided, at its peripheral edge, with a slot 44, which is fit to abut on the edge of the corresponding blade.
Likewise, each second abutment means 41 includes one or more rotating disks, whose number corresponds to the number of the creasing disks of the respective second cutting means 40.
The abutment means first 40 and second 41 of each abutment head 10 are synchronously rotated in the same direction of the same quantity by sixth actuator means 54, through second transmission means 11. These last ones include transmission shafts, first 12 and second 39, rotated by sixth actuator means 54 and to which the abutment means, respectively second 41 and first 40, of each abutnent head 10 are slidably connected. Particularly, the shafts 12, 39 have one or more key-ways for a feather and the rotating disks of the abutment means second 41 and first 41 are directly keyed thereto. Transmission shafts, first 12 and second 39, are kinematically coupled together by means of a chain or a timing belt or a train of gears.
The abutment assembly 9 further includes third guide means 42, fixed to the frame 49 of the machine 1 and fit to slidably support the plurality of abutment heads 10. Particularly, there are second rack means 26 or equivalent means, for instance a timing belt or a chain, which are fixed to said third guide means 42 and to which the fifth actuator means 53 of the plurality of abutment heads 10 are coupled, through respective pinion gears. Each of the actuator means first 51, second 52, fifth 53 and sixth 54 consist of at least a rotary motor of electric or pneumatic type. Particularly each of the actuator means second 52 and fifth 53 can consist of an electric direct current ratio-motor or a brushless motor, while the first actuator means 51 can consist of an brushless or step motor or of a three-phase induction motor.
Each of the actuator means third 23 and forth 33 is constituted by a pneumatic or hydraulic cylinder or by an electric linear actuator.
The feeding assembly 2 includes a couple of parallel and opposed rolls, upper 17 and lower 18, capable to pick the cardboard portion 100 that enters the machine and to longitudinally move said portion 100 through said machine 1.
The lower roll 18 is motorized, while the upper roll 17 is idle and rocking between a spaced condition from and a close condition to the lower roll 18, in order to allow respectively to insert and to move the cardboard portion. Preferably, one or more pneumatic pistons drive said upper roll 17, between the spaced and close conditions.
There are further provided position sensor means 19, for instance an incremental or absolute
rotating encoder, connected to the upper roll 17 in order to measure the longitudinal displacement of cardboard portion 100 and thus the position thereof in the machine in every instant.
The machine is fully controlled by calculation and control electronic means which are connected to the sensor means 19 and which are fit to control the phase relation of feeding assembly 2, first working assembly 3, second working assembly 5 and abutment assembly 9.
During the operation of the machine 1 the feeding assembly 2 picks a cardboard portion 100 and longitudinally moves the latter, through the working assemblies first 3 and second 5.
At the working assemblies 3 and 5, the corresponding operating heads first 4 and second 6 cut, punch, crease said portion 100, respectively in transversal direction and in longitudinal direction with respect to the machine 1, in such a way to manufacture a predefined cardboard blank 101.
Particularly, the first operating head 4, driven by first actuator means 51, can transversally translate and execute continuous or discontinuous working on the cardboard portion 100. By driving the third actuator means 23 of the first operating head 4, it is possible to rotate the first carriage means 24 and consequently to bring in contact with the cardboard 100 the first cutting means 20 or the first creasing means 21, respectively in the transversal cut condition A and in the transversal creasing condition B.
The second cutting means 30 and the second creasing means 31 of each second operating head 6, longitudinally cut, punch and crease by virtue of the longitudinal sliding of the cardboard portion 100, which is moved forwards by the feeding assembly 2 and which is driven at the same time by the abutment assembly 9. In fact, the>abutment means first 40 and second 41 of each abutment head 10 bear against the respective second cutting means 30 and second creasing means 31, and they move said cardboard 100, by virtue of the synchronous rotation thereof, carried out by sixth actuator means 54.
By driving the forth actuator means 33 of each second operating head 6 it is possible to bring in contact with the cardboard portion 100 the second cutting means 30 in the longitudinal cut condition C, the second creasing means 31 being always in contact with said portion 100 in the longitudinal creasing condition D.
The second operating heads 6 and the abutment heads 10 can be automatically positioned in transversal direction by virtue of the respective actuator means second 52 and fifth 53.
It is important to highlight that by positioning the operating heads first 4 and seconds 6 in transversal direction, namely orthogonal to the feed direction of cardboard portion 100, it is possible to execute thereon also particular working, for instance punchings, and to execute symmetrical and asymmetrical cuts, incisions, creasings and punches.
The machine 1 can be manually fed by inserting in the feeding assembly 2 the initial edge of a cardboard web or the first sheet of a continuous sheet module or, alternatively, the machine can be automatically fed. In this case, the machine 1 is upstream connected to a cardboard web feeder or continuous module sheet feeder, provided with a device for inserting the initial edge or the initial sheet between the upper roll 17 and lower roll 18 of the feeding assembly 2.
In the variant shown in figure 6, the machine 1 has the abutment assembly 9 which includes a couple of parallel side by side rolls, first 35 and second 36, fit to support the cardboard portion 100 and to mate respectively the second cutting means 30 and the second creasing means 31 of the respective second operating heads 6 in the longitudinal cut condition C and in the longitudinal creasing condition D. Preferably, the first roll 35 is made of elastic material, for instance a cutproof and wearproof rubber, while the second roll 36 is made of galvanized metallic alloy.
The rolls 35 and 36 are rotated by sixth actuator means 54 to move in exit the worked cardboard portion 100, namely the blank 101.
It is further provided in this variant that each second operating head 6 of the second working assembly 5 has seventh actuator means 37 capable to move the second creasing means 31 between a longitudinal ceasing condition D, wherein they bear against the cardboard portion 100 in order to longitudinal crease, and a removed condition F, wherein the second creasing means 31 are removed from the cardboard.
The operation of said variant is not different from that of the preferred embodiment.
Other advantage is that to provide a machine not requiring stops and manual operations to set and to adjust the tools for manufacturing a different blank.
Further advantage is to provide a machine having a high output, fit to operate with single sheets or continuous sheets or web of cardboard, minimizing the waste of material and notably reducing the manufacturing times of some type packaging blanks.
Other advantage is to provide a reliable machine, safe for the operators