Patent Application
20200361728
The invention relates to separating a blank from a stack of similar blanks.
The process of packaging products often includes the use of blanks to form boxes, cartons, and separators. These blanks are typically flat pieces of inherently laminar materials such as cardboard or paper. Blanks are often delivered in stacks. This means that a blank must somehow be separated from the stack before use.
Machines for separating blanks from a stack of similar blanks often rely on moving belts that run parallel to each other. In many cases, there are between four and eight of these belts. These belts form loops that extend between two axles. The belts cooperate to engage a blank's surface and to pull the blank away from the stack.
Because these belts repeatedly contact blanks, they tend to wear out. It is therefore necessary to replace them. However, the belts do not wear out at the same rate. In particular, the belts near the middle tend to wear out sooner. To replace these belts, it is often necessary to dismantle the machine, including the outer belts. This leads to long downtimes during repairs and maintenance.
In order to accommodate different formats of blanks, the belts must sometimes be rearranged. For example, if a blank is large, more belts will be needed to move it. The task of adding and removing belts and arranging them at the correct location is a complicated and time-consuming process.
The invention provides a straightforward way to adjust a separating machine for separating blanks from a stack of such blanks to accommodate different blank formats while being easy to maintain, and in particular, by providing a way to easily replace defective components thereof.
In one aspect, the invention features an apparatus for separating blanks from a stack of blanks. Such an apparatus comprises a drive unit, a drive shaft that interacts with the drive unit, and at least one ejecting belt, hereafter referred to as a “belt,” that can be driven by the drive shaft. The belt is a constituent of a “belt cassette,” which is hereafter referred to by the more concise term, “cassette.”
The arrangement of each belt at an individual cassette makes it possible for the belts to be replaced in a particularly straightforward manner individually and separately from one another in the event of a defect or for maintenance, for example to replace a worn belt. In addition, due to the modular structure of the cassettes, it is possible for the number of belts and the position and space between them to be varied in any desired manner. This makes it possible for the apparatus to be adjusted to the particular blanks that are to be separated from a stack of such blanks. This also makes it a simple matter to reconfigure the apparatus to accommodate different blank formats.
A modular and exchangeable cassette according to the invention includes a belt guided such as to circulate, a transfer means for transferring the movement of a drive unit of the apparatus onto the belt, in particular using a toothed wheel, as well as at least one securing means to secure the cassette to the apparatus and to detach it easily to carry out a modular exchange of one cassette for another.
The modular nature of the cassette allows one to easily detach the cassette as a single unit or module and to attach a replacement cassette of the same type in its place. This makes it possible both to maintain an inventory of spare cassettes to be used to replace worn belts and to reconfigure the belts to separate different blanks of different sizes, thicknesses, widths, surface structures, and textures and shapes, all of which collectively define the “format” of the blank.
In another aspect, the invention features a method that includes adjusting an apparatus for separating blanks from a stack of such blanks. The method includes aligning a toothed drive wheel at an axial position of a drive shaft followed by a securing a cassette to the apparatus, in particular to one, and preferably two, accommodation rails, hereafter referred to as simply “rails,” of the apparatus. This is carried out in such a way that the toothed drive wheel interacts with a toothed transfer wheel of the cassette to drive the belt.
A method along the lines of the foregoing makes it possible to individually adjust the apparatus to accommodate a wide variety of blank formats and to place the cassette on any of a continuum of locations along the drive shaft. This means that the cassette can be placed at any position rather than in one of a finite number of predefined stops.
As used herein, “blank” refers to any stackable item that is essentially flat. In some embodiments, the blank is formed as one piece. Examples of blanks include individual pieces of paper, board, wood, metal, plastic, or a composite material. In a typical embodiment, the blanks to be separated from a stack have the same shape and thickness. In some embodiments, the blank comprises cardboard that has been cut to shape. Such blanks find use as intermediate or base layers in a package, such as a package for beverage bottles or cans on a pallet. Such blanks also find use for producing containers, such as boxes, folding cartons, carriers, or trays.
As used herein, “separating” refers to removing a blank from a stack of similar blanks so that it can be further processed or conveyed to another apparatus. In principle, the individual blank can be taken from any location within the stack. However, in most cases, the blank is removed from the underside of the stack.
Embodiments include those in which the drive unit rotates the drive shaft using two interacting toothed wheels. In some embodiments, a countershaft connects a motor drive to the drive shaft.
In some of these embodiments, the drive unit comprises one or more motors, in particular electric motors. In some embodiments, the drive unit is a motor drive integrated into the apparatus, such as an electric motor.
In some embodiments, at least one motor is at the apparatus. However, as an alternative, it is also possible for the drive unit to rely, for rotation thereof, on a motor that lies outside the apparatus.
In some embodiments, the drive shaft is secured so that it rotates relative to the apparatus and so that it extends along a a significant portion of the apparatus. Among these are embodiments in which the drive shaft extends along 80% of the length of the apparatus, embodiments in which the drive shaft extends along 90% of the apparatus, and embodiments in which the drive shaft extends along the entire length of the apparatus.
In some embodiments, the drive shaft is formed as one piece.
In yet other embodiments, the drive shaft includes at least one toothed wheel for interacting with a drive unit.
The drive shaft need not have a circular cross section along a plane that is perpendicular to the longitudinal axis. In some embodiments, the drive shaft's cross section deviates from being circular by being flattened. Some embodiments have a cross section in which only one individual region is flattened. In other embodiments, the cross section has two or more flattened sections along what would have been its circumference had it been a circle but is now, as a result of having been flattened in sections, merely its perimeter. In some of these embodiments, the drive shaft has a square cross section. In others of these embodiments, the drive shaft has a rectangular cross-section. In yet other embodiments, the drive shaft has a quadratic cross-section.
The belt is configured as an endless belt, strip, band, chain, or any structure that has the properties of a strip, band, or chain. In some embodiments, the belt is one piece. In other embodiments, the belt has a smooth surface on both sides. In some embodiments, the belt is a flat band made of an elastic plastic or rubber, metal, and/or a composite material. In other embodiments, the belt is a “V” belt. In yet other embodiments, belt comprises ribs on one surface. Among these are embodiments in which the belt has ribs shaped like wedges, trapezoidal ribs, or ribs shaped like a parallelepiped.
As used herein, a “belt cassette,” or more concisely, “a cassette,” is a modular structure that has a belt for engaging a blank. The belt is arranged to contacts a surface of the cassette at the same time that it contacts a blank as it begins the process of separating the blank from the stack of blanks. A cassette is further defined as connecting a single belt to the drive shaft in such a way that the belt can be driven by the drive shaft alone and independently of other belts. Thus, there is no direct connection between two belts from two different cassettes.
In some embodiments, each cassette is arranged at right angles to the drive shaft such that the angular velocity vector of the belt has the same direction as the angular velocity vector of the drive shaft.
The cassette is both modular and exchangeable with other cassettes. As such, the cassette has the property of remaining functionally viable even after having been removed, as a whole from, the apparatus. The cassette also has the property of being able to be secured again to the apparatus or to be replaced by another cassette that is also modular and exchangeable with the replacement being such as to not require any structural change to the remainder of the apparatus for separating of blanks from a stack of such blanks.
As a result of being modular, the cassette is detachable from the drive axle as a complete and unchanged component. This is in part because the cassette is connected to a structure selected from the group consisting of the drive axle, the drive wheel coupled to the axle, and both the drive axle and the drive wheel coupled to the drive axle directly using a structure selected from the group consisting a pinion, a toothed wheel, a gear arrangement, a drive belt, and drive chains.
In some embodiments, the drive shaft and drive wheels that are arranged on the drive shaft are independent of the cassettes, independent of the cassette's securing arrangement, and independent of the cassette's securing means. Such independence can be achieved by having the drive shaft and/or drive wheels be arranged to not be enclosed, carried, or mounted on the cassette or one of the components belonging to it, in particular its carrying structure and bearing plates. As a result, the drive shafts and any related drive are held and mounted independently of the cassettes.
As used herein, a “transfer means” for transferring movement of a drive device onto the belt refers to a component or module that transfers a rotational movement of the drive shaft onto the belt. In particular embodiments, such transfer occurs using a single toothed wheel that transfers the rotational movement directly onto a component that rolls at the belt.
In some embodiments, the securing means includes a device that relies on a positive fit to arrange the cassette on the apparatus. In other embodiments, the securing means relies on a device that arranges the belt on the apparatus in the absence of a positive fit.
As used herein, “securing means” specifically excludes the actual joining of material either by welding or adhesive bonding.
In some embodiments, the securing means causes a positive fit that secures the cassette in at least two spatial directions. Other embodiments rely on a combination of a positive fit in at least one direction and on a non-positive fit in another direction. An example of a securing method that does not rely on a positive fit is one in which securing occurs as a result of a screw being pressed against another structure. Among these are embodiments in which the securing method in the absence of a positive fit relies on at most one screw. As used herein, “securing” refers to a process in which the cassette is caused to remain at a fixed position while nevertheless being able to be detached again from that position or moved from that position while retaining its structural integrity.
In some embodiments, the cassette is secured as a module to the apparatus so that it is easily attached and detached. This amounts to reversible securing. As a result of this feature, it is possible to exchange cassettes in a particularly straightforward manner without further parts of the apparatus having to be dismantled.
It is recognized, of course, that given any two attached components, it is always possible to detach them from each other. Thus, there would be a temptation to broadly construe any two parts as at least to some extent detachable from each other.
This construction is hereby declared to be inconsistent with the specification. After all, there are many cases in which components are detached from other components without the detachment being reversible and modular in nature. For example, when an article is pulverized or otherwise destroyed, many parts are detached from other parts. However, this type of detachment is not what is meant.
In some embodiments, the reversible securing means relies on a screw, a bolt, a pin, a split pin, a latch, or any structure that has the properties of either a bolt, a pin, a split pin, or a latch. As a result, the reversible securing means permits the cassette to be repeatedly removed or detached and then reattached.
A detachable module is understood to be a cassette consisting of a plurality of structural elements. These structural elements are connected to one another and continue to be connected to one another even when the cassette is not attached to anything. As such, the cassette does not need to be arranged at the apparatus in order for cassette to retain its functional capacity and structural stability. The cassette is accordingly stable in its shape and function whether or not it is separated from the rest of the apparatus.
In some embodiments, the cassette is arranged so that it is inserted from above the apparatus to interact with the drive shaft.
In some embodiments, the number of cassettes present can be changed so that there are between one and ten cassettes secured to the drive shaft in such a way that the belts of all cassettes run parallel to each other. Among these are embodiments in which between three and eight cassettes are secured to the drive shaft in such a way that the belts of all cassettes run parallel to each other. In other embodiments there are seven cassettes secured to the drive shaft in such a way that the belts of all seven cassettes run parallel to each other.
In some embodiments, the cassettes are arranged such that the belts of all the cassettes are coplanar, thereby cooperating to form a single transport surface. In other embodiments, all the cassettes are identical and/or arranged completely parallel to one another at the apparatus. In some of these embodiments, the cassettes are arranged so that the distance between individual belts is at least fifty millimeters. In others of these embodiments, the cassettes are arranged so that the distance between individual belts is at least one-hundred millimeters. In yet others of these embodiments, the cassettes are arranged so that the distance between individual belts is at least one-hundred and five millimeters.
In some embodiments, the cassette, and in particular all the cassettes, are secured to the carrying structure either using a positive fit or a non-positive fit. As a result, is becomes a simple matter to correctly align the cassettes in relation to the apparatus as a whole, and in particular, in relation to the drive shaft. In such embodiments, the drive shaft is secured in a way that permits it to rotate relative to the carrying structure. Among these are embodiments in which the drive shaft is actually secured the carrying structure in such a way that it is able to rotate relative to the carrying structure.
As used herein, a “carrying structure” is a structure that provides a place for other structural elements, such as the cassettes and the drive shaft, to be secured. Examples of carrying structures include frames, carriers, profiles, and structures with the properties of frames, carriers, or profiles. Carrying structures are typically solid. A typical material from which a carrying structure is made is metal.
In some embodiments, the carrying structure comprises two rails that run parallel to the drive shaft. In such embodiments, the cassettes can be secured in any desired position on the rails in the axial direction of the drive shaft. This permits the apparatus to be easily adjusted to accommodate different blank formats.
In those embodiments that have rails, it is preferable for the rails to be parallel. In such cases, the cassette bridges the rails.
In those embodiments that have rails, it is preferable for the rails to extend over most of the apparatus. Particular embodiments include those in which the rails extend across at least 75% of the length of the apparatus, those in which the rails extend across at least 90% of the length of the apparatus, and those in which the rails extend across the entire length of the apparatus.
The extent to which the rails extend across the apparatus defines an accommodation region for the cassettes. In some embodiments, the accommodation region comprises a groove or a slot for accommodating a securing means, such as a screw, or a securing element that can be secured in the accommodation region.
In some embodiments, the cassette includes at least one holding element that secures the cassette to the carrying structure, for example to at least one of the rails. Such a holding element promotes the ability to reliably secure the cassette at a particular position. In some embodiments, only one screw at the holding element is needed to carry out this task.
In some embodiments, there are two holding elements. These are typically placed at each end of the cassette near the region at which the belts direction of motion reverses as a result of being deflected.
A holding element is a structure that is secured firmly to the cassette, for example to the cassette's bearing plates. A typical holding element has a region that is used for either positively securing or non-positively securing the cassette to the rail or to an accommodation element on the rail. In many cases, the holding element is secured to the cassette using screws, for example with two screws per bearing plate. In a preferred embodiment, each holding element has an opening for a screw that secures the holding element to the carrying structure, the rail, or an accommodation element on the rail.
In a preferred embodiment, an accommodation element serves as an intermediary between the holding element and the rail. In such an embodiment, the holding element is secured to the accommodation element and the accommodation element is secured at any desired position on the rail. This means that cassettes are easily arranged along the axial direction of the drive shaft. This makes it simple to adjust the apparatus to accommodate different blank formats.
In a preferred embodiment, an accommodation element has a first part and a second part secured to each other, for example by one or two screws. The first part is arranged on a first surface of the rail; the second part is arranged on an opposed second surface of the rail. In a particularly preferred embodiment, at least one of the two parts passes through a slot in the rail. Such a slot extends over a significant portion of, if not the entire length of, the rail.
In some embodiments, the accommodation element comprises an accommodation surface that matches the shape of a corresponding surface of the holding element. These surfaces cooperate to form a positive fit upon contact.
In a preferred embodiment, toothed wheels or gears transmit rotation of the drive shaft. Among these are embodiments in which a toothed drive-wheel secured to the drive shaft engages a toothed transfer-wheel of the cassette to drive the belt. This results in a particularly simple and precise way to actuate one or more cassettes.
In yet other embodiments, the cassette includes a toothed belt-disk for driving the belt. The toothed belt-disk connects to the toothed transfer-wheel in a torsion-resistant manner. In such embodiments, the toothed transfer-wheel connects directly to the toothed belt-disk to drive the belt. Such a connection is established, in some of these embodiments, by using a screw to screw them together. In other embodiments, the torsion-resistant connection between the toothed transfer-wheel and the toothed belt-disk arises from their sharing a common axle.
In some embodiments, the toothed drive-wheel connects to the drive shaft in a way that allowed to be freely displaced along the drive shaft. This means that the drive shaft, with the toothed drive-wheel, is also adjustable based on the position of a cassette. In these embodiments, the toothed drive-wheel and the drive shaft are secured through a non-positive fit along the axial direction. However, along the circumferential direction, the securing can be carried out using a non-positive fit, for example using one or more screws, or by a positive fit, for example by having a drive shaft with a non-circular cross section that mates with a corresponding opening in the toothed-drive wheel or by using a bolt, a pin, or a screw that is extends radially from the drive shaft and is secured to the drive shaft and to the drive toothed wheel.
With a further advantageous embodiment of the invention, the belt runs on two opposing sides of the cassette by means of a toothed wheel disk and a toothed belt wheel, wherein the toothed belt disk and the toothed belt wheel are in each case secured to a bearing plate of the cassette, as a result of which a particularly simple while at the same time particularly stable structure of the cassette is achieved, and, as well as this, by releasing one of the bearing plates, a change of the belt is possible in a particularly simple manner. For particular preference, the bearing plates form the side walls of the cassette. For particular preference, too, the toothed belt disk and/or the toothed belt wheel are mounted on bearings, in particular in each case by means of a slide bearing, ball bearing, roller bearing, or the like. For further preference, the holding elements, in particular a front and a rear holding element, are secured to the bearing plates in such a way, in particular screwed securely to them, that these form the frame or the housing of the cassette. In this situation, the housing can be open on the other sides, and/or the belt can run in sections outside the housing.
In some embodiments, the cassette comprises at least one guide element for the belt. Among these are embodiments in which the guide element surrounds all sides of the ejecting belt.
Among the foregoing embodiments are those in which the guide element is arranged in a region of the cassette at which a section of the belt emerges from the cassette or runs on its surface so that it can engage blanks for separating them from the stack.
Also among the foregoing embodiments are those in which the guide element guides the belt along a contact element. This ensures that, while separating blanks from a stack of such blanks, the contact element supports the side of the belt that is opposite the side that faces the blanks that are being separated from the stack. Among these embodiments are those in which screws or another attachment mechanism secure the contact element opposite bearing plates that form the cassette's housing.
In some embodiments, the cassette also has a tensioning roller that holds the belt under tension. Among these are embodiments in which the tensioning roller onto the belt by contacting the belt on the side thereof that faces the interior of the cassette.
Among the embodiments that feature a tensioning roller are those in which a tensioning roller arm secures the roller to the cassette, and in particular, to a bearing plate. In some of these embodiments, the arm adjusts relative to the cassette to change the belt tension. Such adjustment can be carried out by turning a screw, such as a hexagonal-head screw. In other embodiments, bearings mount the tension roller onto the tensioning roller arm.
Some embodiments feature an accommodation element that can be secured to the apparatus, preferably to at least one accommodation rail, and particularly preferably to each of the accommodation rails, to align the drive toothed wheel that corresponds to the accommodation element. The securing of the cassette then follows the alignment. As a result, it is simple to arrange the cassettes in a repeatable manner at consistent positions along the apparatus.
An exemplary embodiment of the apparatus according to the invention is explained in greater detail hereinafter by reference to the drawings, in which:
Each cassette 5 has holding elements 8, 9 on opposite sides thereof. As shown in
A pair of bearing plates 15a, 15b defines a lateral housing for the cassette 5, as shown in
A drive unit 2 having toothed wheels drives a drive shaft 3 that is secured to the carrying structure 6 in such a way that it is free to rotate relative to the carrying structure 6. The drive unit 2 comprises a countershaft 20, which is best seen in
As the drive shaft 3 turns, it turns the driving wheel 11. The driving wheel 11 turns the transfer wheel 12, which then turns the belt disk 13 that ultimately drives the belt 4 as shown in
The belt 4 forms a loop that extends along the length of the cassette 5 as shown in
Referring to
On the lower side of the cassette 5, a tensioning roller 16 mounted to a distal end of a pivot arm 17 controls how much tension the belt 4 experiences. It does so by deflecting the belt 4. In the illustrated embodiment, the pivot arm 17 pivots about an axle about which the belt wheel 14 rotates.
As can be seen in
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2016 110 944.4 | Jun 2016 | DE | national |
This is the national stage under 35 USC 371 of international application PCT/EP2017/063300, filed on Jun. 1, 2017, which claims the benefit of the Jun. 15, 2016 priority date of German application DE 102016110944.4, the contents of which are herein incorporated by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2017/063300 | 6/1/2017 | WO | 00 |
