Gripper arrangement with adjustable drop behavior

Abstract

Gripper arrangement (3) comprising: a main body (13); a holding device (33); a structural element (15) having a first edge (18) and a second edge (19); and a belt (25) extending around the first edge (18) and the second edge (19) to form an upper run (27) providing a support surface (29) for receiving a product (11); wherein the structural element (15) is movably attached to the main body (13) along a working axis (17) defined relative to the main body (13); wherein the holding device (33) is configured to hold a region of the belt (25) such that movement of the structural element (15) along the working axis (17) causes the belt (25) to rotate around the first edge (18) and the second edge (19);wherein the gripper arrangement (3) is configured to be brought into a first configuration in which, when the structural element (15) moves along the working axis (17), a region of the belt (25) forming the upper run (27) does not move along the working axis (17); and wherein the gripper arrangement (3) is configured to be brought into a second configuration in which, when the structural element (15) moves along the working axis (17), a region of the belt (25) forming the upper run (27) does move along the working axis (17).

Description

The invention relates to the field of gripper arrangements for handling products, in particular for handling food products. EP 1 986 941 B1 discloses a pick-and-place device for picking up and repositioning an article supported by a support surface. The device comprises a first part with a plate section that is movable parallel to the support surface, such that a leading edge of the plate section penetrates between the article and the support surface. The device also includes a band made of a flexible material. The band is wrapped around at least the leading edge of the plate section, so that it lies between the plate and the article when the plate penetrates beneath it. EP 1 685 045 B2 discloses a tool for picking up food products from a conveyor belt. The tool comprises two blades that are movable between a first position and a second position. In the first position, the leading edges of the blades are separated by a large gap. In the second position, the leading edges overlap, are in contact with each other, or are separated by a smaller gap. The entire tool can be rotated about a vertical axis to rotate the product. EP 4 059 672 A1 discloses a gripper arrangement for attachment to a robot. The gripper arrangement comprises a first jaw and a second jaw, which are movable relative to each other from a gripping position to an open position. To release the food product, the first jaw is moved relative to the second jaw from the gripping position to the open position, such that one side of the food product is not supported by the first jaw, while another side of the food product temporarily rests on the second jaw, resulting in the food product tilting about a longitudinal axis. The object of the invention is to provide an improved way of handling products with a gripper arrangement. According to a first aspect of the invention, a gripper assembly is provided. The gripper assembly comprises a main body, a holding device, a structural element, and a belt. The structural element has a first edge and a second edge. The belt extends around the first and second edges, thus forming an upper run. The upper run provides a support surface for receiving a product. The structural element is movably attached to the main body along a working axis defined relative to the main body. The holding device is configured to hold a portion of the belt such that movement of the structural element along the working axis causes the belt to rotate around the first and second edges. The gripper assembly is configured to be brought into a first configuration.In the first configuration, the upper run of the belt does not move along the working axis when the structural element moves along it. The gripper assembly is configured to be moved into a second configuration. In the second configuration, the upper run of the belt does move along the working axis when the structural element moves along it. The gripper assembly can be configured to pick up a product at a receiving location, so that the product is picked up onto the platform. The gripper assembly can be configured to move the product, picked up onto the platform, to a delivery location. The gripper assembly can be configured to deliver the product to the delivery location. The band can be positioned between a product placed on the support surface and the structural element. The band can provide a suitable surface for receiving the product. By holding a section of the belt in place with the holding device, the belt can be rotated around the first and second edges as the structural element moves along the working axis, without requiring a separate drive for the belt. The holding device can be configured to hold the belt section in place relative to the main body. In the first configuration, moving the structural element along the working axis shifts the position of the upper run along the working axis. However, this occurs without any movement of the belt section forming the upper run along the working axis. In the first configuration of the gripper arrangement, moving the structural element along the working axis shifts the belt beneath a product lying on the support surface along the working axis without changing the absolute position of the product in space. In the first configuration, the belt can be pushed under the product by moving the structural element along the working axis, without the product sliding along the working axis on the belt. In this first configuration of the gripper arrangement, the product can be picked up on the support surface with reduced friction. In this first configuration, the product can be picked up on the support surface with a reduced risk of damage. In the first configuration, the structural element can be moved along the working axis to pull the belt away from under the product without the product sliding on the belt. This allows the product to be dispensed gently and with reduced friction. In the second configuration of the gripper arrangement, the position of the upper run can be shifted along the working axis by moving the structural element. In this case, a section of the belt forming the upper run performs a movement along the working axis. In the second configuration, the upper run of the belt can, when the structural element moves along the working axis, move together with a product lying on the support surface. In the second configuration, the product lying on the support surface can be moved along the working axis in space when the structural element moves along the working axis. In the second configuration of the gripper arrangement, moving the structural element along the working axis can impose a movement on the product along the working axis. The gripper assembly can be selectively configured in either the first or second configuration. This allows switching between two operating modes. The operating mode can be adjusted depending on the task at hand, thus optimizing the gripper assembly's operation. The first and second edges can be parallel to each other. The first and second edges can be perpendicular to the working axis. The first axis can lie in a horizontal plane. The second axis can lie in a horizontal plane. The gripper assembly can be configured to be attached to a robotic system. The robotic system can be configured to move the gripper assembly, in particular from a pick-up location to a drop-off location. The gripper assembly can include a coupling device for attachment to the robotic system. The coupling device can be stationary relative to the main body of the gripper assembly. The coupling device can be attached to the main body of the gripper assembly. The holding device can be configured to hold the belt in a holding position along a direction of rotation of the belt around the first and second edges. The holding device can also be configured to hold the belt along a holding axis perpendicular to the working axis. This holding axis can be perpendicular to a direction of rotation of the belt around the first and second edges. The holding axis can extend along a width direction of the belt. The holding device can be configured to hold a section of the upper run in the first configuration. In the first configuration, the section of the belt held by the holding device can be a section of the upper run. The holding device can be configured to hold a section of the upper run relative to the main body in the first configuration. In the first configuration, the holding axis can be located on the upper run. The holding device can be configured to hold a section of the lower run of the belt in the second configuration. In the second configuration, the section of the belt held by the holding device can be a section of the lower run. The holding device can also be configured to hold a section of the lower run relative to the main body in the second configuration. In the second configuration, the holding axis can be located on the lower run. The holding device can be adjustably mounted on the main body between a first holding position and a second holding position. By adjusting the holding device between the first and second holding positions, the gripper arrangement can be adjusted between the first and second configurations. When the holding device is in the first holding position, the gripper arrangement can be in the first configuration. When the holding device is in the second holding position, the gripper arrangement can be in the second configuration. The first and second holding positions can be defined relative to the main body. The gripper assembly can include a holding device drive configured to adjust the holding device on the main body between the first holding position and the second holding position. The holding device drive can include a linear actuator. The linear actuator can, for example, be a pneumatic cylinder or a linear motor, in particular a servo linear motor. To adjust between the first holding position and the second holding position, the holding device can be moved along an axis perpendicular to the working axis. Alternatively, the holding device can be moved along an axis that is at least substantially vertical. The strap can be connected to the holding device, for example, by one or more loops. The structural element can be configured to move in a picking motion in a first direction along the working axis to a picking position defined relative to the main body in order to pick up a product on the platform. During the picking motion in the first direction along the working axis, the structural element and the belt can be slid under a product so that the product is picked up on the platform. The gripper assembly can be in its first configuration during the picking movement. The structural element and the belt can be pushed under the product during the picking movement without the product moving along the working axis. The first edge of the structural element can be positioned downstream of the second edge of the structural element with respect to the first direction along the working axis. The first edge can be flat and / or have a thickness that decreases along the first direction to facilitate product pickup. The structural element can be configured to move in a second direction along the working axis in a dropping motion to release a product picked up on the platform. The second direction can be opposite to the first. The gripper assembly can be in the first configuration during the ejection movement. If the gripper assembly is in the first configuration during the ejection movement, the product can be ejected over the first edge. If the gripper assembly is in the first configuration during the ejection movement, the structural element and the belt can be pulled away from the product along the working axis without the product moving along the working axis. This can facilitate the product being ejected in the orientation in which it lies on the support surface. The gripper assembly can be in the second configuration during the ejection movement. If the gripper assembly is in the second configuration during the ejection movement, the product can be ejected over the second edge. If the gripper assembly is in the second configuration during the ejection movement, the structural element and the belt can perform a translational movement along the working axis. Simultaneously, a section of the belt forming the upper run can perform a relative movement along the working axis with respect to the structural element. Through this relative movement between the section forming the upper run of the belt and the structural element, the product can change its position on the structural element along the working axis, effectively being conveyed along the structural element. In particular, the product can be conveyed beyond the second edge and thus ejected from the support surface.If the gripper arrangement is in the second configuration during the ejection movement, a velocity can be imposed on the product along the working direction. This velocity can be parallel to the second direction along the working direction. A velocity along the second direction, when the product is conveyed over the second edge, tends to rotate around its own axis, particularly around a horizontal axis. This allows the product's orientation to be changed upon ejection. For example, it can be achieved that the product rotates during and / or after leaving the support surface and lands on a receiving surface rotated at a desired angle, particularly substantially 180 degrees. The gripper assembly can be configured to be in either the first or second configuration during the ejection movement. The gripper assembly can be configured to be in the first configuration during the ejection movement if the product is to be ejected without rotation. The gripper assembly can be configured to be in the second configuration during the ejection movement if the product is to be ejected with rotation. The gripper assembly can be configured to move the structural element at a first speed during a dispensing motion when the gripper assembly is in its first configuration. The gripper assembly can also be configured to move the structural element at a second speed during a dispensing motion when the gripper assembly is in its second configuration. The first speed can be greater than the second speed. A fast movement of the structural element can facilitate dispensing the product without rotation. A slow movement of the structural element can facilitate rotation of the product during dispensing. If the product is conveyed slowly beyond the second edge, a portion of the product that has already passed the second edge may hang downwards, thus initiating rotation of the product. The second speed can be less than 80 percent, or less than 60 percent, or less than 50 percent, or less than 40 percent, or less than 20 percent of the first speed. The gripper assembly may include a guide element. The second edge may be located along the working axis between the guide element and the first edge. When the product is dropped over the second edge, the guide element may influence the product's falling motion by contacting the product. The guide element may be configured to assist and / or guide the product's rotation during its falling motion. The guide element may extend at least substantially parallel to the first edge and / or the second edge. The guide element may have at least substantially a U-shaped cross-section. The guide element may be designed as a guide plate. The guide element may be stationary relative to the main body. The guide element may be attached to the main body. According to a second aspect of the invention, a system for handling products is provided. The system comprises a gripper arrangement according to the first aspect of the invention. Furthermore, the system includes a transfer surface for providing products and a receiving surface for receiving products. The gripper arrangement can be configured to pick up products from the transfer surface and drop them onto the receiving surface. The system may include a control unit. The control unit may be configured to determine whether a product picked up on the gripper assembly's platform should be ejected with or without rotation. The control unit may be configured to control the gripper assembly to perform the ejection movement in the first configuration if it has been determined that the product should be ejected without rotation. The control unit may be configured to control the gripper assembly to perform the ejection movement in the second configuration if it has been determined that the product should be ejected with rotation. The system can include a robotic unit. The gripper assembly can be attached to the robotic unit. The robotic unit can be configured to move the gripper assembly, in particular by a translational movement. The robotic unit can be configured to move the gripper assembly to a receiving location where a product is picked up from the transfer surface. The robotic unit can be configured to move the gripper assembly to a delivery location where the product is dropped from the carrying surface onto the receiving area. According to a third aspect of the invention, a use of the gripper arrangement of the first aspect or the system of the second aspect is provided. The gripper arrangement or the system is used to selectively drop a product picked up on the support surface onto a receiving surface, depending on the situation, either in such a way that the rotational position of the product about a horizontal axis remains essentially constant during the drop, or in such a way that the rotational position of the product about the horizontal axis changes by essentially 180 degrees during the drop. The horizontal axis can be an axis defined in relation to the product. The horizontal axis can be an axis inherent to the product itself. According to a fourth aspect of the invention, a method for transporting products using a gripper assembly is provided. The gripper assembly comprises a structural element and a belt. The belt extends at least around a first edge of the structural element, thus forming an upper run. The upper run provides a support surface for receiving a product. A portion of the belt is held by a retaining device of the gripper assembly. A receiving movement is performed by moving the structural element in a first direction along a working axis defined with respect to a main body of the gripper assembly into a receiving position. During the receiving movement, the belt rotates around the first edge and is pushed under a product, so that the product is received on the support surface formed by the upper run. It is determined whether the product is to be released without rotation or with rotation.A ejection motion is performed by moving the structural element from the receiving position along the working axis in a second direction opposite to the first. During the ejection motion, the belt rotates around the first edge. The product is then ejected from the support surface formed by the upper run onto a receiving surface. If it is specified that the product is to be ejected without rotation, the structural element moves in the second direction at a first velocity during the ejection motion. If it is specified that the product is to be ejected with rotation, the structural element moves in the second direction at a second velocity during the ejection motion. The second velocity is lower than the first. A movement of the structural element at the higher first velocity can favor the product being ejected without rotation. A movement of the structural element at the lower second velocity can favor the product rotating upon ejection. The second speed can be less than 80 percent, or less than 60 percent, or less than 50 percent, or less than 40 percent, or less than 20 percent of the first speed. Discarding the product without rotation can include discarding the product in the orientation in which the product was located on the support surface of the gripper assembly. A product drop with rotation can involve the product rotating around its own axis during the drop. This axis can be horizontal. During a drop with rotation, the product can rotate in such a way that it lands on a receiving surface in an orientation 180 degrees reversed from its original orientation on the gripper assembly. The product can have a first side and a second side opposite the first. If a product lying with its first side facing down on the launching surface is dropped without rotation, it may land with its first side facing down on the receiving surface. If a product lying with its first side facing down on the launching surface is dropped with rotation, it may land with its second side facing down on the receiving surface. The product in question could be a food product. For example, it could be a fish fillet. One of the two product sides could be composed predominantly of skin, and the other of the two product sides could be composed predominantly of flesh. Determining whether the product should be ejected without rotation or with rotation can be achieved by ejecting the product onto another product already on the receiving surface in such a way that two identical product sides end up facing each other. This prevents, for example, the skin side of a fish fillet from coming into contact with the flesh side of a fish fillet below, thus avoiding potential contamination of the flesh side. After picking up the product, the gripper assembly can be moved to a dispensing position by a translational movement. The dispensing position can be located above a receiving surface for the product. The dispensing position can be selected depending on whether the product is to be dispensed without rotation or with rotation. If it has been determined that the product is to be dropped without rotation, the gripper assembly can be moved to a first height above the receiving surface. If it has been determined that the product is to be dropped with rotation, the product can be moved to a second height above the receiving surface. The second height can be greater than the first. A greater drop height can promote rotation of the product upon release. A lower drop height can promote drop without rotation. According to one embodiment, the product can be ejected over the first edge, regardless of whether it is specified that the product should be ejected without rotation or with rotation. The first edge can be the edge over which the product enters the receiving surface during the picking movement. The band can also extend around a second edge of the structural element. The product can be released over the first edge if it has been specified that the product should be released without rotation. The product can be released over the second edge if it has been specified that the product should be released with a rotation. The second edge can extend parallel to the first edge. The first edge can lie downstream of the second edge with respect to the first direction along the working axis. The first edge and / or the second edge can extend perpendicular to the working axis. The upper run of the belt cannot move along the working axis during the discharge movement if the product is to be discharged without rotation. The upper run of the belt can move along the working axis during the discharge movement if the product is to be discharged with rotation. Features, explanations, and descriptions relating to one aspect of the invention can be applied to or combined with any other aspect of the invention. The gripper arrangement and the system can be suitable, designed, and / or configured for carrying out the method or the use. The method and the use can be carried out using either the gripper arrangement or the system. The invention is further explained below with reference to embodiments and the figures. Fig. 1 shows a schematic representation of a system with a gripper arrangement according to one embodiment before picking up a product. Fig. 2 shows a schematic representation of the gripper arrangement after picking up the product. Fig. 3 shows a schematic representation of the gripper arrangement when the product is dropped without rotation. Fig. 4 shows a schematic representation of the gripper arrangement when the product is dropped with rotation according to a first embodiment. Figs. 5, 6 to 7 show a sequence when the product is dropped with rotation according to a second embodiment. Fig. 1 shows a schematic representation of a system 1 with a gripper arrangement 3, which has a coupling device 5. The gripper arrangement 3 is attached to a robot assembly 7 by means of the coupling device 5. The robot assembly 7 is configured to move the gripper arrangement 3 in a translational motion in space. Fig. 1 shows a situation before the gripper assembly 3 picks up a product 11 lying on a transfer surface 9. The gripper assembly 3 comprises a main body 13 to which the coupling device 5 is attached. The gripper assembly 3 also comprises a structural element 15, which in the illustrated embodiment is designed as a plate. The structural element 15 is guided on the main body 13 for movement along a working axis 17. The structural element 15 comprises a first edge 18 and a second edge 19. With respect to a first direction 21, which extends along the working axis 17, the first edge 18 is located downstream of the second edge 19. With respect to a second direction 23 opposite to the first direction 21, which also extends along the working axis 17, the second edge 19 is located downstream of the first edge 18. The gripper arrangement 3 comprises a belt 25 which wraps around the first edge 18 and the second edge 19. The belt 25 forms an upper run 27, which provides a receiving surface 29 for the product 11. The belt 25 also forms a lower run 31. The upper run 27 and the lower run 31 extend parallel to each other. The gripper assembly 3 comprises a holding device 33. In the illustrated embodiment, the holding device 33 comprises a rod which extends perpendicular to the working axis 17 in a horizontal plane. The holding device 33 holds a section of the belt 25 in relation to the main body 13. In the illustrated embodiment, the belt 25 is attached to the rod of the holding device 33 by a loop 35. The gripper arrangement 3 includes a structural element drive 37. The structural element drive 37 is configured to move the structural element 15 along the working axis 17. System 1 comprises a control unit 39, which is configured to control the gripper assembly 3. The control unit 39 can be part of the gripper assembly 3 or be provided externally to the gripper assembly 3. The control unit 39 can be a control unit of a higher-level system. The control unit 39 can be a control unit of the robot assembly 7. In the operating situations shown in Figs. 1, 2, 3 to 4, the holding device 33 secures a section of the upper run 27. This results in the gripper device 3 being in a first configuration. In the first configuration, a section of the belt 25 forming the upper run 27 does not move along the working axis 17 when the structural element 15 moves along the working axis 17. Conversely, a section of the belt 25 forming the lower run 31 moves along the working axis 17 in the first configuration when the structural element 15 moves along the working axis 17. To move the product 11 from the position shown in Fig. 1 onto the support surface 29, the structural element 15 is moved in the first direction 21 along the working axis 17 by means of the structural element drive 37, thereby pushing the structural element 15 and the belt 25 under the product 11. This occurs without any sliding movement of the product 11 on the belt 25. The resulting position, in which the product 11 is positioned on the support surface 29, is shown in Fig. 2. After picking up product 11, the robot device 7 moves the gripper arrangement 3 to a delivery position in order to then drop the product 11 onto a receiving surface 41. Fig. 3 shows the situation where the product 11 is to be dropped onto the receiving surface 41 without rotation. The gripper assembly 3 was moved to a first height 43 above the receiving surface 41. Subsequently, the structural element 15 is moved at a first speed in the second direction 23 along the working axis 17, so that the structural element 15 and the belt 25 are pulled away from under the product 11. The product 11 then falls onto the receiving surface 41. On the receiving surface 41, the product 11 is in at least substantially the same orientation as it was when it was picked up on the support surface 29, as shown by the dashed lines in Fig. 3. If, however, the product 11 is to be dropped rotated 180 degrees about a horizontal axis 45 of the product 11 relative to its orientation on the support surface 29, the dropping movement is carried out in a different manner. Two variants of the invention are described for this purpose.The dropping of the product 11 with rotation according to a first embodiment of the invention is described with reference to Fig. 4. In the first embodiment, the gripper arrangement 3 for dropping the product 11 with rotation about the axis 45 of the product 11 is moved into a dispensing position in which the gripper arrangement 3 is located at a second height 47 above the receiving surface 41. Subsequently, the structural element 15 is moved in the second direction 23 along the working axis 17 at a second speed, so that the structural element 15 and the belt 25 are, in effect, pulled away from under the product 11. The second speed is lower than the first speed. A lower speed promotes rotation of the product 11 about the axis 45 of the product 11 as the product 11 falls downwards onto the receiving surface 41. The second height 47 is greater than the first height 43.A greater drop height favors a rotation of the product 11 about the axis 45 of the product 11 during the fall onto the receiving surface 41. As shown in dashed lines in Fig. 4, the product 11 comes to lie on the receiving surface 41 in an orientation which is rotated by 180 degrees compared to the orientation in which the product 11 was on the receiving surface 29. In both the first embodiment of the invention and the second embodiment described below, the gripper arrangement 3 is in the first configuration when picking up the product 11 (transition between Fig. 1 and Fig. 2) and when dropping the product 11 without rotation (Fig. 3), in which the upper run 27 is held by the holding device 33. In the first embodiment, the gripper arrangement 3 is also in the first configuration when dropping the product 11 with rotation about the axis 45 of the product 11 (Fig. 4). In the first embodiment, the holding device 33 can be fixedly attached to the main body 13 of the gripper arrangement 3. Picking up and dropping product 11 without rotation are carried out in the second embodiment of the invention in the same way as in the first embodiment. However, dropping product 11 with rotation about its axis 45 is carried out differently in the second embodiment than in the first embodiment. This is described with reference to Figures 5, 6 to 7. In the second embodiment of the invention, the holding device 33 can be adjusted so that it holds the lower run 31. This is achieved by moving the holding device 33 downwards in a vertical direction by means of a holding device drive 47, which can, for example, be designed as a pneumatic cylinder. If the product 11 is to be dropped with a rotation about the axis 45 of the product 11, in the second embodiment of the invention, after picking up the product 11, the gripper arrangement 3 is brought into the second configuration by moving the holding device 33, in which the holding device 33 holds the lower run 31. The resulting state is shown in Fig. 5. Since the lower run 31 is held by the holding device 33 in the second configuration, a movement of the structural element 15 along the working axis 17 does not result in a movement of a region of the belt 25 forming the lower run 31 along the working axis 17 in the second configuration. However, a region of the belt 25 forming the upper run 27 does move along the working axis 17 in the second configuration when the structural element 15 moves along the working axis 17. In the second embodiment of the invention, to eject the product 11, the structural element 15 is moved at the second speed in the second direction 23 along the working axis 17 by rotating the product 11 about its axis 45, while the gripper arrangement 3 is in the second configuration. This causes the product 11 to move in the second direction 23 along the working axis 17 with respect to both the main body 13 and the structural element 15. Optionally, the movement of the structural element 15 in the second direction 23 can occur at least partially while the gripper arrangement 3 is being moved into the dispensing position. In Fig. 6, the gripper arrangement 3 is provided in the delivery position at the second height 47 above the receiving surface 41 and the product 11 has already reached the second edge 19 of the structural element 15. From the situation shown in Fig. 6, the structural element 15 is moved further in the second direction 23 along the working axis 17, so that the product 11 is conveyed beyond the second edge 19 of the structural element 15. Due to the movement of the upper run 27 of the belt 25, the product 11 has a velocity in the second direction 23 along the working axis 17 when it is conveyed over the second edge 19. This promotes a rotation of the product 11 about its axis 45. Preferably, the movement of the structural element 15 in the second direction 23 along the working axis 17 is continued when the product 11 is already hanging at least partially downwards over the second edge 19. This gives the product 11 a spin as it falls onto the receiving surface 41, which promotes a rotation of the product 11 about its axis 45. The product 11 comes to lie on the receiving surface 41 in an orientation rotated by 180 degrees compared to the orientation in which the product 11 was on the support surface 29, as shown in dashed lines in Fig. 7. As shown in Fig. 7, the gripper arrangement 3 can include a guide element 70 which, by contacting the product 11, influences a falling movement of the product 11 when the product 11 is dropped over the second edge 19 and promotes a rotation of the product 11.

Claims

Gripper arrangement (3) comprising: a main body (13); a holding device (33); a structural element (15) having a first edge (18) and a second edge (19); and a belt (25) extending around the first edge (18) and the second edge (19) to form an upper run (27) providing a support surface (29) for receiving a product (11); wherein the structural element (15) is movably attached to the main body (13) along a working axis (17) defined relative to the main body (13); wherein the holding device (33) is configured to hold a region of the belt (25) such that movement of the structural element (15) along the working axis (17) causes the belt (25) to rotate around the first edge (18) and the second edge (19);wherein the gripper arrangement (3) is configured to be brought into a first configuration in which, when the structural element (15) moves along the working axis (17), a region of the belt (25) forming the upper run (27) does not move along the working axis (17); and wherein the gripper arrangement (3) is configured to be brought into a second configuration in which, when the structural element (15) moves along the working axis (17), a region of the belt (25) forming the upper run (27) does move along the working axis (17). Gripper arrangement according to claim 1, wherein the holding device (33) is configured to hold a region of the upper run (27) in the first configuration. Gripper arrangement according to claim 1 or 2, wherein the holding device (33) is configured to hold a portion of a lower run (31) of the belt (25) in the second configuration. Gripper arrangement according to one of the preceding claims, wherein the holding device (33) is adjustably mounted on the main body (13) between a first holding position and a second holding position, and wherein the gripper arrangement (3) is adjustable between the first configuration and the second configuration by adjusting the holding device (33) between the first holding position and the second holding position. Gripper arrangement according to one of the preceding claims, wherein the structural element (15) is configured to move in a picking movement in a first direction (21) along the working axis (17) into a picking position defined relative to the main body (13) in order to pick up a product (11) on the support surface (29), wherein the gripper arrangement (3) is preferably in the first configuration during the picking movement. Gripper arrangement according to one of the preceding claims, wherein the structural element (15) is configured to move in a dropping motion in a second direction (23) along the working axis (17) in order to drop a product (11) picked up on the support surface (29). Gripper arrangement according to claim 6, wherein the product (11) is thrown over the first edge (18) by the throwing motion when the gripper arrangement (3) is in the first configuration during the throwing motion, and the product (11) is thrown over the second edge (19) by the throwing motion when the gripper arrangement (3) is in the second configuration during the throwing motion. Gripper arrangement according to one of the preceding claims, wherein the gripper arrangement (3) is configured to move the structural element (15) at a first velocity during a drop-off movement in which the gripper arrangement (3) is in the first configuration, and to move the structural element (15) at a second velocity during a drop-off movement in which the gripper arrangement (3) is in the second configuration, wherein the first velocity is greater than the second velocity. Gripper arrangement according to one of the preceding claims, wherein the gripper arrangement (3) further comprises a guide element (70), wherein the second edge (19) is provided along the working axis (17) between the guide element (70) and the first edge (18), and wherein the guide element (70) is configured to influence a falling movement of the product (11) when the product (11) is dropped over the second edge (19) by contacting the product (11). Use of a gripper arrangement (3) according to one of the preceding claims to selectively drop a product (11) picked up on the support surface (29) onto a receiving surface (41) in such a way that the rotational position of the product (11) about a horizontal axis (45) remains essentially constant during the drop, or in such a way that the rotational position of the product (11) about the horizontal axis (45) changes by essentially 180 degrees during the drop. Method for transporting products (11) with a gripper arrangement (3), wherein the gripper arrangement (3) comprises a structural element (15) and a belt (25), the belt (25) extending at least around a first edge (18) of the structural element (15) and thus forming an upper run (27) which provides a support surface (29) for receiving a product (11); wherein a region of the belt (25) is held by a holding device (33) of the gripper arrangement (3); and wherein the method comprises: performing a picking movement by moving the structural element (15) along a working axis (17) defined with respect to a main body (13) of the gripper arrangement (3) in a first direction (21) into a picking position, wherein the belt (25) during the picking movement is moved around the first edge (18) and pushed under a product (11) so that the product (11) is picked up on the support surface (29) formed by the upper run (27);Determine whether the product (11) is to be ejected without rotation or with rotation; and perform a ejection movement by moving the structural element (15) from the receiving position along the working axis (17) in a second direction (23) opposite to the first direction (21), wherein the belt (25) rotates around the first edge (18) during the ejection movement and the product (11) is ejected from the support surface (29) formed by the upper run (27) onto a receiving surface (41); wherein the structural element (15) is moved in the second direction (23) at a first velocity during the ejection movement if it has been determined that the product (11) is to be ejected without rotation, and is moved in the second direction (23) at a second velocity during the ejection movement if it has been determined that the product (11) is to be ejected with rotation, the second velocity being less than the first velocity. Method according to claim 11, wherein the gripper arrangement (3) is moved to a first height (43) above the receiving surface (41) when it has been determined that the product (11) is to be dropped without rotation, and is moved to a second height (47) above the receiving surface (41) when it has been determined that the product (11) is to be dropped with a rotation, wherein the second height (47) is greater than the first height (43). Method according to claim 11 or 12, wherein the product (11) is thrown over the first edge (18) irrespective of whether it has been determined that the product (11) is to be thrown without rotation or with a rotation. Method according to claim 11 or 12, wherein the band (25) further extends around a second edge (19) of the structural element (15), wherein the product (11) is ejected over the first edge (18) if it has been determined that the product (11) is to be ejected without rotation, and wherein the product (11) is ejected over the second edge (19) if it has been determined that the product (11) is to be ejected with a rotation. Method according to one of claims 11 to 14, wherein a region of the belt (25) forming the upper run (27) does not move along the working axis (17) during the discharge movement if it has been determined that the product (11) is to be discharged without rotation, and wherein the region of the belt (25) forming the upper run (27) performs a movement along the working axis (17) during the discharge movement if it has been determined that the product (11) is to be discharged with a rotation.

Images