DEVICE AND METHOD FOR DISPENSING OBJECTS WITH NON-ROTATIONALLY SYMMETRICAL BASE

Description

[0001] The present application relates to a device for discharging objects such as containers, bundles, packages with axially symmetrical surfaces that are transported on a transport device.

[0002] Such reject devices are used, for example, to sort out defective beverage bottles or other empty or already filled food containers or packaging. The transport device can be a conveyor belt, link chain conveyor, or similar. During the reject process, the objects are often moved from a first conveyor to a second, parallel conveyor. Typical reject devices can operate even at bottle throughputs of up to 90,000 bottles per hour. At such high speeds, however, even minor irregularities can lead to objects tipping over, thus significantly limiting system productivity.

[0003] In conventional reject devices, objects to be rejected are pushed onto adjacent, parallel conveyors using transverse impulses that are as small as possible. The transverse impulses are kept as small as possible to minimize the risk of the objects tipping over.

[0004] To keep the required transverse impulse as low as possible, the diversion element can be individually controlled, allowing the transverse impulse to be adjusted depending on the nature of the object to be diverted. For this purpose, object parameters such as the weight or center of gravity of the objects to be diverted can be determined. The diversion element can then be controlled specifically based on these parameters.

[0005] In the case of objects with a rotationally symmetrical base, such as the typically used cylindrical glass or reusable PET beverage bottles, tipping of the objects during discharge can be largely avoided.

[0006] However, with the cylindrical disposable PET beverage bottles typically used, it has been shown that, despite optimizing the control of the reject device to the aforementioned object parameters, the reject objects tip over relatively frequently. This is particularly the case when the objects are to be rejected from one conveyor to another, and is also particularly the case when the objects have to overcome height differences during rejection.

[0007] From the publication JP S60 53728 U, a device for transporting and aligning containers is known. The containers are essentially rotationally symmetrical and have a flattened portion in the base area. The flattened portion of the containers interacts with an alignment element of the device, whereby the containers are arranged in a predetermined orientation on the railing. In this orientation, the containers are then fed to a subsequent process, in particular labeling. In particular, JP S60 53728 U discloses a device for aligning and orienting objects, each having an axially symmetrical base, wherein the axially symmetrical base has the shape of a regular polygon with three-, five-, or seven-fold axis symmetry, comprising an alignment device designed to align the objects in a predetermined orientation, a transport device,on which the objects are conveyed in a single row and spaced from one another from the alignment device to a downstream device, and at least one railing which is provided on one side of the transport device at least in the region of the alignment device, wherein the alignment device is designed such that the objects are pressed against the railing and are thereby aligned such that an axis of symmetry of the standing surface in the transport plane extends perpendicular to this railing, and the objects are then fed to the diverting device in this orientation.

[0008] The object of the present invention is therefore to further improve the diversion method and to further reduce the risk of tipping over of the objects to be diverted, in particular in the case of objects to be diverted with a non-rotationally symmetrical base.

[0009] This object is achieved in the device of the type mentioned at the outset by the features of claim 1 and by a method having the features of claim 4.

[0010] The device for diverting objects, each with an axially symmetrical base, wherein the axially symmetrical base has the shape of a regular polygon with three-, five-, or seven-fold axial symmetry, comprises an alignment device and a diverting device, as well as a transport device on which the objects are conveyed in a single row and spaced from one another from the alignment device to the diverting device. At least one railing is provided on one side of the transport device, at least in the area of the alignment device. The alignment device is designed such that the objects are pressed against the railing, then roll along the railing and align themselves such that an axis of symmetry of the base of the objects extends in the transport plane perpendicular to this railing. The objects are then fed to the diverting device in this orientation.The diversion device is oriented in such a way that one of the corners of the object's base points in the direction in which the objects are diverted.

[0011] In one embodiment, the base of the objects consists of a closed support surface. The closed support surface can then, for example, have the shape of a regular polygon or star with three, five or seven corners. In a preferred embodiment, the base consists of individual, spaced-apart support surfaces. In this case, the axisymmetric base is to be understood as the entire area formed by the individual support surfaces, wherein the support surfaces are then each arranged at the corners of a regular triangle, pentagon or heptagon. Preferably, the objects to be diverted have a base in the shape of a regular triangle, pentagon or heptagon. Preferably, the objects to be diverted have a base in the shape of a regular pentagon. Preferably, the base in the shape of a regular pentagon consists of five individual support surfaces.

[0012] Objects within the meaning of the present invention can be containers such as glass bottles, plastic bottles, containers, cans, bundles, or other packaging items. These terms are used largely synonymously in this description. Reusable containers typically have rotationally symmetrical base surfaces. Disposable containers, on the other hand, often have non-rotationally symmetrical base surfaces. Disposable PET containers with a base consisting of five individual support surfaces are particularly common. These are arranged axially symmetrically at the vertices of a regular pentagon. The present invention is also suitable for use in the diversion of objects with regular triangular or heptagonal base surfaces.

[0013] Beverage containers, in particular, often have a substantially cylindrically symmetrical shape, regardless of the geometry of their base. Reusable beverage containers typically exhibit a cylindrically symmetrical shape across their entire height. They possess a cylindrically symmetrical body with a rotationally symmetrical base. Disposable beverage containers, in contrast, often exhibit a cylindrically symmetrical body with a non-rotationally symmetrical base. Typically, the cross-section of the container transitions from an axially symmetrical base within a base region to a substantially rotationally symmetrical cross-section. This base region usually extends up to a few centimeters and has a geometry that corresponds to the geometry of the base.

[0014] The lateral railing according to the invention is designed to interact with the axially symmetrical base area of the objects. If the objects have additional sections with a cross-section corresponding to the geometry of the base, the railing can also interact with one of these additional sections. In this description, the peripheral section of the object that interacts with the railing for the purpose of aligning the objects is generally referred to as the "axially symmetric peripheral section."

[0015] In the present application, a surface or cross-section is referred to as "rotationally symmetrical" if a rotation by any angle around a point maps the surface onto itself.

[0016] In this application, a surface or cross-section is referred to as "axisymmetric" if it is imaged onto itself by axial reflection about its axis of symmetry. A surface or cross-section can also have multiple axes of symmetry. A surface referred to as "axisymmetric" in this application can also be a surface that is imaged onto itself by rotation through certain angles around a point. However, the term "axisymmetric" is explicitly not intended to encompass rotationally symmetric surfaces in this application.

[0017] When diverting objects with axially symmetric but not rotationally symmetric bases, it has been shown that the success of the divert depends significantly on the orientation of the base. Surprisingly, it has been found that tipping is least likely when the objects are diverted in an orientation where one of the corners of the base points exactly in the direction in which the divert is to occur. In this orientation, the divert then occurs along a symmetrical axis of the base.

[0018] Objects transported in a single row and spaced apart from each other are typically conveyed on conveyors with railings on both sides. The objects alternately come into contact with one of the two railings. Friction with the railing causes the objects to rotate clockwise and counterclockwise, continuously changing their orientation. To ensure controlled rotation of the objects, it is important to ensure that they only roll off one railing.

[0019] According to an embodiment of the invention not according to the invention, the railing along which the objects are to roll in the area of the alignment device is arranged at an acute angle to the original transport direction of the transport device. The objects conveyed by the transport device are lightly pressed against the inclined railing due to the static friction between their standing surface and the transport device and roll along it. The greater the angle at which the railing is arranged, the greater the pressure force with which the objects are pressed against the railing. In principle, the angle can be selected as desired and can be adapted to suit the transport task. However, it has proven particularly advantageous that angles of less than 5° and more preferably angles between 1° and 3° are sufficient to apply the necessary pressure force.Under this inclination, sufficiently long alignment devices can be provided without having to increase the width of the transport device.

[0020] This embodiment is technically particularly easy to achieve, since no additional components or changes to other components are required.

[0021] However, pressing the objects against the railing can also be achieved in other ways. For example, the railing can be arranged parallel to the transport device, but the transport device can be tilted slightly so that the containers are pressed against the railing due to the downward force.

[0022] In a further embodiment not according to the invention, a pressing device can be provided that gently presses the objects against the railing. Such a pressing device can, for example, be a brush device mounted on the side opposite the railing, which gently presses the individual objects against the railing with its bristles. The device must be selected such that it is still possible for the objects to roll off the railing.

[0023] For the alignment device to function, providing a railing on one side of the transport device is sufficient. However, to increase operational safety, a railing can also be provided on the other side of the transport device.

[0024] The length of the alignment device should preferably be adjustable to the transport task. Since the objects usually only need to rotate around a portion of their circumference, it is often sufficient for the length of the alignment device to roughly correspond to the object's circumference.

[0025] The railing can, in principle, have any shape, as long as it is shaped to interact with the section of the object that has a cross-section that corresponds to the geometry of the object's base. The railing is preferably rail-shaped and is mounted at the height of the axially symmetrical peripheral section of the objects to be transported. The vertical extension of the floor area can vary from object type to object type, so the railing is preferably adjustable and can be moved both vertically and horizontally so that it can be adapted to the geometry of the objects to be transported.

[0026] Further preferably, the railing is constructed from multiple elements, for example at least two rails. A first rail, also called the alignment rail, is arranged at the level of the axis-symmetrical circumferential section of the objects. Since the axis-symmetrical circumferential section of the objects is usually the base section of the objects, the alignment rail is usually arranged only a few millimeters above the transport device. With railing rails this low, there is always the risk that the objects will tip over the rail and out of the transport device. To prevent objects from falling out in this way, it is advantageous to provide an additional railing rail, also called a guide rail. The guide rail is preferably arranged at the level of a rotationally symmetrical circumferential section of the objects. For objects that are typically transported, the guide rail is attached approximately at the level of the object's center.

[0027] The guide rail is preferably arranged parallel to the alignment rail. The guide rail is preferably offset laterally relative to the alignment rail. The lateral offset of the guide rail depends on the circumference of the objects. The lateral offset should preferably be selected so that the objects only come into contact with the guide rail when they are in the desired diversion orientation. Multiple guide rails can also be used.

[0028] It is of course also possible to provide a conventional railing on the second side of the transport device in order to prevent the objects on this side of the transport device from tipping over.

[0029] The objects align themselves automatically in the alignment device as described below. The objects are aligned as described in Fig. 1 shown by a transport device to the alignment device. The objects come into contact with the alignment rail, which is arranged at an angle to the original transport direction, in the area of the alignment device. Generally, the objects will have such an orientation that there is a contact point between the object and the alignment rail. At this contact point, the object rolls along the alignment rail until a second contact point comes into contact with the alignment rail, as shown in Fig. 1 is indicated. For typically used objects, this position already corresponds to the desired diversion orientation. In this orientation, an axis of symmetry of the base runs perpendicular to the alignment rail. In addition, the distance between the object center and the alignment rail is smallest in this orientation, so that the guide rail can only come into contact with the object in this position. As soon as the object has assumed this orientation, further rotation of the object is prevented. Further rotation of the object would mean that the object center would have to move away from the alignment rail again. However, this is counteracted by the contact pressure with which the respective object is pressed against the alignment rail. The object therefore remains in this orientation and is guided in this orientation to the diversion device.

[0030] The diversion device can be any diversion device known to those skilled in the art. Typically, ejectors or pushers are used for this purpose. These are arranged perpendicular to the transport device and impart a transverse impulse to the object to be diverted. The transverse impulse pushes the object to be diverted from the transport device, for example, onto a second parallel transport device. Particularly when slight differences in height occur between the transport devices, the risk of the objects tipping during diversion increases. Instead of a pusher, other diversion devices such as those described in patents EP 0 003 111 B1, EP 0 019 117 B1 or EP 1 438 245 B1 can also be used.

[0031] The present invention also relates to a method for diverting objects, each having an axially symmetrical base, wherein the axially symmetrical base has the shape of a regular polygon with three-, five-, or seven-fold axis symmetry. The method comprises conveying the objects on a transport device, aligning the objects conveyed from the transport device by means of an alignment device, and diverting the aligned objects by means of a diverting device. The objects are transported on the transport device in a single row and spaced apart from one another from the alignment device to the diverting device.The transport device has a side railing at least in the area of the alignment device. The alignment device is designed such that the objects are pressed against the side railing and align themselves in such a way that an axis of symmetry of the axially symmetrical base of the objects extends perpendicular to the side railing in the transport plane. The diverting device is oriented such that one of the corners of the base of the objects points in the direction in which the objects are to be diverted.

[0032] The diversion device is preferably a pusher located on the same side as the side railing. This pushes the aligned objects down from the transport device perpendicular to the transport direction from the side opposite the pusher. The objects can then be moved, for example, to another transport device or to a collection area.

[0033] Features described in connection with individual embodiments can also be used in connection with other embodiments, unless otherwise stated.

[0034] Embodiments of the invention are explained below with reference to the drawings. They show: Fig. 1 a plan view of a diversion device according to the invention; Fig. 2 Side view in transport direction of the Fig. 1 bottle shown at the beginning of the alignment device; Fig. 3 Side view in transport direction of the Fig. 1 bottle shown at the end of the alignment device;

[0035] Fig. 1 shows an embodiment of the diverting device according to the invention comprising a transport device 10, an alignment device 12 and a diverting device 14. Objects 16 are transported on the transport device. As indicated by the dashed circles, the objects 16 are essentially cylindrical and thus rotationally symmetrical. The base 18 of the objects 16, however, is not rotationally symmetrical, but axially symmetrical with a five-fold axis of symmetry. This is indicated by the club-shaped structures with solid lines. The objects 16 can, for example, be typically used disposable PET bottles, whose base 18 is formed by five symmetrically arranged support surfaces 18a, b, c, d, e. The individual support surfaces 18a, b, c, d, e are aligned in the shape of a regular pentagon. As can also be seen from the cross sections of the Figuren 2 and 3As can be seen, the individual support surfaces 18a, b, c, d, e usually do not extend to the outer circumference of the bottles 16, but are arranged slightly offset from the bottle center. The pentagonal arrangement of the base surface 18 also continues within a base region 20 of the bottle 16, with the bottle cross-section within this base region 20 gradually transitioning from the axially symmetrical pentagonal shape of the base surface 18 into a rotationally symmetrical circular bottle cross-section.

[0036] It was surprisingly found that for bottles 16 with non-rotationally symmetrical base 18, the success of the rejection process depends significantly on the orientation of the base 18 of the bottles 16 during the rejection process. For typically used disposable PET bottles 16 with bases 18 with five-fold axial symmetry, as in Fig. 1 As shown, tipping of the bottles 16 during the rejection process can most likely be avoided if the base 18 is aligned so that one of the five support surfaces 18a,b,c,d,e points in the direction in which the bottle 16 is to be rejected. The bottle 16, which is in Fig.1 in the area of the diversion device, is already in the optimal orientation for diversion. In this orientation, one of the axes of symmetry of the base 18 of the bottle 16 extends perpendicular to the railing 22 provided in the area of the alignment device 12.

[0037] In order to feed the bottles 16 in the desired orientation to the discharge device 14, an alignment device 12, as shown in Fig. 1 is shown. The alignment device 12 essentially consists of a two-part rail-shaped railing 22, which is arranged at an acute angle α of approximately 1-2° with respect to the transport device 10 on the right-hand edge of the transport device 10 in the conveying direction. Due to the friction between the transport device 10 and the standing surface 18 of the bottles 16, each bottle 16 is gently pressed against the railing 22, which is arranged at an angle to the transport device 10.

[0038] The two-part railing 22 comprises a first railing, the alignment rail 24, which is arranged at the level of the axially symmetrical base area 20 of the bottles 16. To prevent the bottles 16 from tipping over, a second railing, the guide rail 26, is also provided. The guide rail 26 is located approximately at the level of the center of the bottles 16 in an area in which the bottles 16 have a rotationally symmetrical cross-section. The guide rail 26 is also arranged slightly offset from the outside of the transport device 10, so that the alignment in Fig. 2 only the floor area 20 comes into contact with the alignment rail 24 of the railing 22. As in Fig. 1 As shown, the bottle 16 then rolls along the alignment rail 24 over the contact point 28a between the first support surface 18a and the alignment rail 24 until the second support area 18b also comes into contact with the alignment rail 24. Further rotation of the bottle 16 could then only occur via the second contact point 28b between the alignment rail 24 and the second support area 18b. However, such (further) rotation is prevented by the continuous frictional pressure of the transport device 10, which presses each bottle 16 against the railing 22.

[0039] Due to the non-rotationally symmetrical shape of the base region 20 of the individual bottles 16, the distance of the rotational axis 30 of the bottles 16 from the guide rail 26 depends on the orientation of the bottles 16. The distance between the rotational axis 30 of the bottles 16 and the guide rail 26 is greatest in the Fig.1 at the top edge of the image. This distance decreases with increasing rotation of the bottle 16. The distance between the rotation axis 30 of the bottle 16 and the guide rail 26 is smallest when the base region 20 of the bottle 16 rests against the alignment rail 24 with both contact points 28a and 28b, i.e. when the bottle is in the desired rejection orientation. The lateral distance of the guide rail 26 is therefore preferably adjusted such that the bottle 16 just touches the guide rail 26 in the desired rejection orientation. This effectively prevents the bottles 16 from tipping over during the alignment process.

[0040] A railing 32 is also provided on the side of the conveyor opposite the alignment device. This railing is not intended to align the bottles, but rather to prevent bottles on this side from tipping off the conveyor.

[0041] Since disposable PET bottles in particular can have a variety of different shapes, it is sensible to design the individual railing rails 24, 26, 32 so that they can be moved so that their position can be adapted to the respective transport task at hand.

[0042] The railing 22 of the alignment device 12 extends to the rejection device 14. A bottle 16 to be rejected is fed to the rejection device 14 in the desired rejection orientation. Fig. 1 In the embodiment shown, the reject device is a conventional pusher, which imparts a transverse impulse to the bottle 16 to be rejected, so that the bottle is pushed sideways by the transport device 10. The reject device 14 is connected to a control device and can be individually controlled according to previously determined object parameters. The objects to be rejected can, for example, be pushed onto a second transport device (not shown). Since the orientation of the bottle 16 to be rejected, as shown in Fig.1 shown, is such that one of the support surfaces 18a,b,c,d,e of the base of the bottle points in the diversion direction 34, the bottle 16 is as stable as possible during the diversion process and the risk of the bottle 16 tipping over is reduced.

[0043] Of course, the described principle of aligning the bottles 16 to be discharged can also be applied to bottles 16 with base surfaces 18 that have a different axis symmetry than a five-fold axis symmetry. List of reference symbols

[0044] 10Transport device 12Alignment device 14Rejection device 16Bottle 18Standing surface 18a,b,c,d,e,Support surface 20Bottle base area 22Railing 24Alignment rail 26Guide rail 28a,bContact points 30Bottle rotation axis 32Guide rail 34Rejection direction

Claims

1. A device for discharging objects (16) each having an axially symmetrical base surface (18), wherein the axially symmetrical base surface has the shape of a regular polygon with a three-, five-, or seven-fold axial symmetry, comprising: an aligning unit (12) configured to align the objects in a predetermined orientation, a discharge unit (14), a transport unit (10), on which the objects (16) are conveyed in a single row and in a mutually spaced manner from the aligning unit (12) to the discharge unit (14), and at least one railing (22) arranged on one side of the transport unit (10) at least in the region of the aligning unit (12), wherein the aligning unit (12) is configured such that the objects (16) are pressed against the railing (22) and are thereby aligned such that an axis of symmetry of the base surface (18) in the transport plane extends perpendicularly to said railing (22) and wherein the objects (16) are then transported to the discharge unit (14) in this orientation, and wherein the discharge unit (14) is oriented such that one of the corners of the base surface of the objects (16) points in the direction in which the objects are discharged, wherein the objects (16) are pressed against the railing (22) by tilting the transport unit (10) in the region of the aligning unit (12).

2. The device according to claim 1, wherein the railing (22) is configured in a rail-shaped form.

3. The device according to any of the previous claims, wherein the rail-shaped railing (22) comprises at least one aligning rail (24) and at least one guide rail (26), and wherein the aligning rail (24) and the guide rail (26) are parallel to each other, but disposed laterally offset relative to the transport direction (10), such that the objects (16) are guided along the guide rail (26) only when the objects (16) have adopted the desired orientation.

4. A method for discharging objects with an axially symmetrical base surface, wherein the axially symmetrical base surface has the shape of a regular polygon with a three-, five-, or seven-fold axial symmetry, comprising the following steps: conveying the objects (16) on a transport unit (10), aligning the objects (16) conveyed on the transport unit (10) using an aligning unit (12) in a predetermined orientation, and discharging the objects (16) aligned in the predetermined orientation using a discharging unit (14), wherein the objects (16) are conveyed on the transport unit (10) in a single row and in a mutually spaced manner from the aligning unit (12) to the discharge unit (14), and wherein the transport unit (10) is provided with a lateral railing (22) at least in the region of the aligning unit (12), wherein the aligning unit (12) is configured such that the objects (16) are pressed against the lateral railing (22) and are oriented such that an axis of symmetry of the axially symmetrical base surface (18) of the objects (16) extends on the transport plane perpendicularly to the lateral railing (22), and wherein the discharge unit (14) is oriented such that one of the corners of the base surface of the objects (16) points in the direction in which the objects are discharged, wherein the objects (16) are pressed against the railing (22) by tilting the transport unit (10) in the region of the aligning unit (12).

5. The method according to claim 4, wherein the discharge unit (14) is preferably a pusher, disposed on the same side as the lateral railing (22), and which pushes the aligned objects (16) substantially perpendicularly to the transport direction off the side opposite of the pusher of the transport unit (10).

6. The method according to any of claims 4 or 5, wherein the objects (16) have at least one peripheral region with an axially symmetrical cross-section corresponding to the base surface (18), and wherein the rail-shaped railing (22) comprises at least one aligning rail (24), fixed at the height of the axially symmetrical peripheral region of the objects (16).

7. The method according to claim 6, wherein the axially symmetrical peripheral region of the objects (16) is disposed at the height of a bottom region of the objects (16), and the aligning rail (24) is exclusively disposed at the height of the axially symmetrical peripheral region of the objects (16).

8. The method according to claim 6 or 7, wherein the objects (16) are essentially pressed against the aligning rail (24) of the railing (22), only.

9. The method according to any of claims 4 to 8, wherein the objects (16) have a rotationally symmetrical peripheral region, and wherein the rail-shaped railing (22) comprises at least one guide rail (26), fixed at the height of the rotationally symmetrical peripheral region of the objects (16).

10. The method according to any of claims 4 to 9, wherein the objects (16) to be discharged have a base surface in the shape of a regular pentagon, and wherein the base surface preferably consists of five individual support areas.

11. The method according to any of claims 4 to 10, wherein the objects (16) to be discharged are plastic bottles, preferably disposable PET bottles, having a cylindrically symmetrical body and a base surface and a contiguous bottom region, wherein the base surface and the bottom region respectively possess the shape of a regular pentagon.