Patent Application
20230079406
The present invention relates to a device for removing straps from boxes, such as straps used around boxes which is to be transported. Straps are removed before un-packaging.
Different kinds of products are packaged in boxes which are secured by straps around the boxes to avoid opening of the boxes. To open and empty the boxes the straps need to be removed. When having large batches of boxes ensured by straps the strap removal is a time-consuming process if performed manually by an operator, and it may be a hard work to drag the straps away from the boxes.
In food processing industries food objects such as fish can be packed in boxes made of expanded polystyrene (Styrofoam) where a lid is placed on the top of each box, and though there may be some kind of meshing between the box and the lid the lid is often secured by two straps around the box and lid. Such straps are often made of a plastic material. A number of these boxes with straps are arranged close to each other on a pallet and transported to a destination where the content is to be processed. When an operator manually cuts and remove the straps he is subjected to a heavy workload as he pulls away the straps due to friction forces appearing from the small volume between the boxes.
U.S. Pat. No. 5,297,329 describes an apparatus for cutting the string ties of products carried on pallet-like supports has at least one cutting unit with a transverse beam arranged above a line for the conveyance of the pallet-like supports so as to be slidable in a direction which is longitudinal to the conveyance line. The unit is moved at a speed equal to the advancement speed of the pallets. Two trucks are slidably mounted on the transverse beam and support a pair of vertically slidable arms. The arms have a cutting element, for automatically locating the string tie to be cut, and an opposite element for gripping the string tie, which cooperates with the cutting element. Rollers for removing the cut string tie cooperate with the gripping element.
U.S. Pat. No. 4,773,148 describes a method of and apparatus for removing tying band where a portion of an endless tying band around a package is displaced from the package thus defining a space between the portion of the tying band and the package. Then, a guide plate is inserted into the space, and the tying band is pressed by the guide roll against the guide plate to grip the tying band between the guide plate and the guide roll. The tying band which is gripped between the guide plate and the guide roll is then severed by a cutter blade. The guide roll is located to deliver an end of the severed tying band for thereby removing the severed tying band from the package.
On the above background it is an object of embodiments of the present invention to provide a device for removing straps from boxes where the device is capable of automatically engaging with a strap and removing it from the box, securing the strap will not disturb opening the boxes or come into contact with the content of the boxes, and hereby reducing the risk of contaminating the content.
A further object of the present invention is to provide a device for removing straps from boxes which apparatus is simple in concept, safe and reliable in operation as well as possible to use in different arrangements for removing straps from boxes, and where the removal of straps from boxes can be performed during movement of the box and/or of the device.
A first aspect of the invention relates to a device for removing straps from boxes, such as a strap encircling a box, the device may comprise a) at least one tentacle or gripping device for creating contact to a strap which is to be removed from a box, b) at least one first guide for guiding the strap away from the tentacle or gripping device, and c) at least one first guide drive for driving the first guide.
In a preferred embodiment the device comprises a device for removing straps from boxes, such as a strap encircling a box, the device comprises
The boxes with straps around may be of any material, such as of cardboard or plastic. Plastic may be hard plastic or softer plastic e.g. expanded polystyrene. The straps may also be of any material such as metal or plastic, preferred is straps made of plastic. Embodiments of the device is exemplified with removal of plastic straps from boxes made of expanded polystyrene, though it should be understood embodiments of the invention would be suitable of removing straps of other materials than plastic and from boxes of other materials than expanded polystyrene.
The at least one tentacle or gripping device may engage with the strap to be removed by being directed in between the strap and the box. A guide driven by a guide drive may engage with the strap and guide the strap away such as downwardly from the box.
The tentacle or gripping device may comprise a pointed tip making it easier to introduce the tentacle or gripping device between the strap and the box. The box with a strap and the tentacle are moved relative to each other such that the strap and the tentacle reach each other and the tentacle becomes positioned between the strap and the box to catch the strap. By further movement of the device and/or of the box the strap is directed downwards by the tentacle and becomes engaged by a guide guiding the strap away from the tentacle and away from the box. Preferably the strap is cut before or at the time the tentacle or gripping device enters between the strap and the box and starts removing the strap from the box.
The device may further comprise at least one runner or holder for positioning the tentacle or gripping device next to a box. The runner or holder may have a fixed position according to the tentacle or gripping device and may be positioned such that it gets in contact with the box and maintains a certain distance between the runner or holder and the box such that the tentacle or gripper may or may not engage with the box material and such that if the tentacle or gripper engages with the box material it does not enter too deeply into the box material. In this way the holder or runner secures the box is not broken with the risk of the content dropping out or the content being contaminated by an entry of the tentacle or gripping device into the box.
The device may further comprise at least one position mechanism for directing the at least one tentacle or gripping device and the at least one holder or runner towards a box and the at least one position mechanism may also be capable of contracting to reduce a force made between the box and the tentacle or gripping device and/or to reduce the force made between the box and the holder or runner (6). The position mechanism applies a force to the tentacle or gripping device and holder or runner hereby pushing the tentacle or gripping device and the holder or runner towards the box. However, the holder or runner when getting in connection with the box obtains or is influenced by a force from the box and transfer this force as a counterforce to the position mechanism, such that the tentacle or gripping device is held in a certain distance from the box, which may be adjacent to the box. The position mechanism may be any mechanism providing a force to the tentacle or gripping device and to the holder or runner and may be a cylinder, such as a pneumatic cylinder. This force is thus pressing the tentacle or gripping device and the holder or runner towards the box. When the force made by the contact between the box and the holder or runner increases above the force applied by the position mechanism, the position mechanism may contract to avoid the tentacle or gripping device and holder or runner engages too much with the box. For some boxes the tentacle or gripping device or the holder or runner should not be allowed to damage the outer surface of the box material, however, for some types of boxes, such as EPS boxes i.e. thermo boxes made of expanded polystyrene, the tentacle or gripping device or the holder or runner could be allowed to damage the outer surface of the box material without contaminating e.g. food products, such as fish, being transported in the boxes. Such damages may be minor scratches in the outer surface when e.g. a robot transports a box pass a device as described herein to remove straps from the box, and when the box becomes positioned on the tentacle or gripping device and/or on the holder or runner small scratches may be made before the tentacle or gripping device and the holder or runner is pressed to the inside of the device as described elsewhere herein.
The at least one first guide for guiding the strap away from the tentacle or gripping device engages with the strap when it is pulled downwards such as by the tentacle or gripping device. The first guide is driven by a guide drive to pull the strap away from the tentacle or gripping device. The strap may only be directed directly from the tentacle or gripping device to the first guide when the position mechanism is in a contracted position.
In an embodiment the device may further comprise at least one second guide for guiding the strap towards the first guide i.e. guiding the strap from the tentacle or gripping device to the first guide. The second guide is preferably located close to the tentacle to be capable of engaging with a strap when this strap has first engaged with the tentacle. The second guide may be driven by a guide drive. The second guide guides the strap away from the tentacle or gripping device and to the first guide which then further removes the strap from the box. The second guide may comprise at least one carrier to engage with the strap and to overcome the force performed onto the strap while this is positioned around the box, such as partly around the box. The second guide may be a belt, such as a belt with carriers, and running in a direction away from the pointed tip of the tentacle or gripping device which engages with a strap to be removed from a box. The second guide runs towards the first guide to bring the strap to this first guide.
The first guide may comprise two belts each comprising a transport area which are located close to each other such as in close connection to each other and running in directions enabling the belts each to apply a force onto a strap entering in between the two belts and directing the strap away from the second guide or away from the tentacle. The first guide may comprise two members, such as pressing members each capable of transmitting forces to one of the running belts and securing the belts are pressed together and are capable of holding and removing the strap from the box when the belts of the first guide has engaged with a strap. Hereby straps will not escape when being caught by the first guide and will not get into contact with processing equipment or in contact with the content of the box, which may be food that should be secured from being contaminated.
The at least one tentacle or gripping device may comprise a land to be guided towards a box on a box side from where at least one strap is to be removed. The land may have similar function as described in respect of the holder or runners.
In an embodiment the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide are connected or controlled as a unit in a way such that they simultaneously can be directed towards or away from a box. This movement is performed by the position mechanism as described elsewhere herein i.e. the at least one position mechanism may be directing the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide towards or away from a box. The unit of the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide may be considered as a top part of the device, and may be exposed to a force such as from the box when getting in connection with the box and where the force results in the top part being pushed inside the device such that the inlet end of the second guide positioned close to the tentacle or gripping device is at a position of the inlet end of the first guide. Hereby the second guide in such situations need not have any separate function for guiding the strap as the inlet of the first guide may engage with the strap when the strap is directed away from the box by the pointed tip of the tentacle or gripping device. The forces applied by the box towards the tentacle or gripping device and to the holder or runner determines if the top part is in its extended position with no or limited force applied by the box, or the top part is in a contracted position where the force applied by the box is pushing the top part to its contracted position. Any position between extended position and contracted position is possible. Hereby the top part will be in an extended position if the box does not push towards the top part, or if the top part does not push towards a box.
In an embodiment, positioning arms secure the top part when moving down and up stays in the correct position relative to the first guide and such that the device is capable of pulling a strap from the second guide to the first guide while the movement is taking place. The positioning arms are preferably connected to the position mechanism which may amend the position of the positioning arms due to the force provided onto the tentacle or gripping device and to the holder or runner.
Due to the function described above this may correspond to directing the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide towards or away from a box simultaneously is directing the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide away or towards the at least one first guide, respectively.
The device of the present invention may be a stand-alone device where boxes with at least one strap which should be removed are directed towards the device described herein. The device may also be positioned between two conveyors e.g. two conveyor belts transporting boxes with at least one strap which should be removed pass the device, or the device may be positioned on a robot arm such that the present device can be directed pass boxes with at least one strap which should be removed. Hereby directing the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide towards or away from a box simultaneously is directing the at least one tentacle or gripping device, the at least one holder or runner and the at least one second guide away or towards the at least one first guide should be understood in respect of how the device is installed i.e. as a stand-alone device, between conveyors or controlled by a robot. In a system where the device is a stand-alone device and boxes are handled by a robot such that the robot directs the boxes pass the stand-alone device or removing cut straps, the position of the top part during the strap removal is determined by the moving curve of the robot and thus by the forces applied to the top part during the movement.
The device may further comprise a cutting device, where such a cutting device may be located to be capable of cutting a strap before or simultaneously with this strap being in contact with the at least one tentacle or gripping device. Such a cutting device may be connected directly to the device described herein such as connected to the top part of the device and in front of the tentacle or gripping device, though preferably not cutting straight ahead the location of the tentacle or gripping device, but preferably at least 5 cm aside from where the tentacle or gripping device is to engage with the strap, such as at least 10 cm aside. Here ‘in front’ means the cutting device will engage with a strap to be removed before the tentacle or gripping device gets into contact with the cut strap and close to the position where the tentacle or gripping device is to engage with the strap.
A cutting device may also be positioned to cut a strap on one of the other sides of the boxes where the tentacle or gripping device does not engage with the strap, such as on the opposite side of the box in respect of where the tentacle or gripping device is to engage with a strap.
A second aspect of the invention relates to a system for cutting and removing straps from boxes, such as a strap encircling a box, the system comprises:
Here the device for removing straps from boxes is preferably a device as described herein.
In the system the cutting device comprises a cutting element such as a knife capable of cutting a strap, such as a plastic strap.
The knife preferably has a cutting depth being smaller than the sum of the thickness of the strap to cut with addition of the thickness of the box side with the strap. More preferably the knife has a cutting depth smaller that the thickness of the box side with the strap. Also, the knife may have a cutting depth substantially equal to the thickness of a strap to cut. This should ensure the knife does not cut through the box with the risk objects in the box may drop out, be cut into and/or become contaminated by the knife which during the cutting processes is in contact with the outside of the box.
The system with the device for removing straps from boxes may further comprise an inlet conveyor such as a conveyor belt and an outlet conveyor such as a conveyor belt for conveying boxes with at least one strap towards and boxes without straps away from the device for removing straps from boxes.
In such a system the cutting device may be located under, above or along a side of a box under transport and at a box side having side lengths or widths being parallel to the transport direction.
In an embodiment of the system the device for removing straps from boxes may further comprise a robot connection unit capable of connecting the system to a robot arm with at least four axes.
The system may further comprise a robot arm and a control unit for controlling the robot arm with the device for removing straps from boxes. Preferably the robot can be controlled in at least five axes, such as at least six axes. Preferred is that the robot can control the movement of the device in all dimensions such that the tentacle or gripping device can engage with a strap located around a box. Preferably this can be performed while the device is being moved by the robot arm and/or the box with at least one strap is being moved.
The system may further comprise a vision system for obtaining images of the boxes with straps, and an image processing unit for processing obtained images to perform an output signal being an input signal for the control unit for controlling the robot arm. The processing unit may be based on the obtained images being capable of controlling the movements of the robot arm with the device to remove straps from boxes.
A third aspect of the invention relates to a method of removing at least one strap from a box, where the method comprises the steps of
The method of removing at least one strap from a box may be by using the device or system as described herein or directing by a robot arm at least one box encircled by a strap pass the device as described herein such that the strap engages with the tentacle or gripping device and is removed from the box.
The method of removing at least one strap from a box by using the system may be where the device is a stand-alone device, the device is located between two conveyors, or the device is controlled by a robot.
It should be understood that features described in respect of one aspect may be used for other aspects described herein as well.
In the shown embodiment the encircled features i.e. the top part 15 can move down such that the second guide 8 is hidden inside the device and only the first guide 5 is used for guiding the strap away from the tentacle or gripping device 4. The device 1 may also be constructed with only the first guide 5 i.e. without the second guide 8 and without the features giving the movable connection between the top part and the main part of the device.
It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20155544.8 | Feb 2020 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/052781 | 2/5/2021 | WO |
