Method and device for separating workpieces

Abstract

The invention relates to a method for removing a plate-shaped first workpiece (12) from an upper side (14) of a stack (16) of further plate-shaped workpieces (18a, 18b) in a sequential direction of the further workpieces (18a, 18b). A gripper (22) moves the first workpiece (12) away from a second workpiece (20), wherein the second workpiece (20) is a workpiece from the stack (16) of further workpieces (18a, 18b), which is adjacent to the first workpiece (12). A separating layer (34) is moved into a gap (46) between a raised corner (23) of the first workpiece (12) and the second workpiece (20), being at least partially pushed over the second workpiece (20) in the process. The first workpiece (12) is moved away from the stack (16) of the further workpieces (18a, 18b).

Description

[0001] Procedures and for separating workpieces

[0002] Background of the invention

[0003] The invention relates to a method for removing a plate-shaped first workpiece from the top side of a stack of further plate-shaped workpieces in the sequential direction of the further workpieces. The invention also relates to a device for separating workpieces, in particular for carrying out such a method.

[0004] DE 11 2012 006 565 T5 discloses a method for separating sheet metal pieces, in which a sheet metal piece is lifted from a stack of sheet metal pieces, whereupon a separating element is inserted between the lifted sheet metal piece and an adjacent sheet metal piece beneath the lifted sheet metal piece. The lifted sheet metal piece is then removed from the stack of sheet metal pieces.

[0005] The disadvantage is that the adjacent sheet can partially adhere to the lifted sheet and be partially moved along with the lifted sheet when the lifted sheet is removed. Separating the lifted sheet from the adjacent sheet takes a comparatively long time and may cause the adjacent sheet to shift or deform.

[0006] Measures to improve separation require additional aids such as compressed air.

[0007] It is therefore an object of the present invention to provide a method for separating plate-shaped workpieces that quickly separates the plate-shaped workpieces from one another in a mechanically simple manner. It is also an object of the invention to provide a device for carrying out the method.

[0008] This object is achieved according to the invention by a method according to claim 1. The features of a device according to the invention are specified in claim 7. Advantageous embodiments emerge from the dependent claims.

[0009] The method according to the invention comprises the following steps: a) lifting the first workpiece by a gripper; b) inserting a separating layer between a raised corner of the first workpiece and a second workpiece from the stack of further workpieces, the second workpiece being adjacent to the first workpiece; c) holding down the stack of further workpieces by the separating layer; d) removing the first workpiece from the stack of further workpieces; e) measuring the thickness of the first workpiece (12).

[0010] By holding down the stack of additional workpieces, the separating layer holds the additional workpieces in their position, in particular also the second workpiece, so that the second workpiece can be separated from the first workpiece relatively quickly without changing its position. By holding down the stack of additional workpieces, it is mechanically stable and ensured that no additional workpieces are separated and removed from the stack with the first workpiece. The separating layer can be moved away from the gripper. There should preferably be no additional aids or contours for separating the first workpiece (e.g. a nozzle for compressed air) that would make gripping the first workpiece more difficult or cause a time delay.Separating a corner is advantageous, among other things, because it simultaneously at least partially separates two adjacent edges of the workpiece, which saves time and money in the process. The separating layer can have at least one nozzle, in particular several nozzles. The nozzle(s) can be provided on an end face of the separating layer. During the process, a gas, in particular compressed air, can flow out of the nozzle(s) at least temporarily. Alternatively, suction can occur through the nozzle(s).

[0011] In step b), the separating layer is moved over at least a portion of the second workpiece that is covered by the separating layer. Holding down is understood in particular to mean that the separating layer blocks movement of this covered portion of the second workpiece toward the first workpiece and / or exerts a force on this portion of the second workpiece that is directed away from the first workpiece. The force is directed toward the other workpieces beneath the second workpiece.

[0012] According to an advantageous embodiment of the method, the gripper is removed from the first workpiece after the separating layer has been inserted between the raised corner and the adjacent second workpiece. This allows a transport device for removing the first workpiece to grip the first workpiece in all sections of its surface.

[0013] In a further embodiment of the method, the stack of further workpieces is shifted and / or pivoted after the separating layer has been inserted between the raised corner and the adjacent second workpiece.

[0014] The second workpiece can be guided along the separating layer to accelerate the separation of the first workpiece from the second. The stack can be moved and / or pivoted using a storage carriage.

[0015] According to a preferred variant of the method, the separating layer is designed as a band. A band preferably has a comparatively large surface area and thus ensures rapid separation of the first workpiece from the second workpiece.

[0016] In particular, measuring the thickness can be used to determine whether only the first workpiece or other workpieces were accidentally lifted and / or removed from the stack of other workpieces. The thickness of the first workpiece can be measured before and / or after inserting the separating layer between the first and second workpieces.

[0017] In a preferred embodiment of the method, the separating layer is inserted between a separating section of the first workpiece, which comprises the raised corner, and the adjacent second workpiece, wherein the separating section comprises the raised corner, an adjacent corner, and an edge between these corners. The separation occurs simultaneously across the entire width of the workpieces between two opposing edges of the respective workpieces, thereby enabling particularly rapid separation.

[0018] A device according to the invention for removing a plate-shaped first workpiece from a top side of a stack of plate-shaped further workpieces in the sequential direction of the further workpieces has the following elements: i) a gripper for gripping the first workpiece, having a drive for moving the gripper along a lifting axis of the device; ii) a separating layer oriented perpendicular to the lifting axis, having a positioning means for moving the separating layer along the lifting axis and perpendicular thereto; iii) a transport device for removing the first workpiece from the stack of further workpieces; iv) a thickness gauge (32) for measuring the thickness of the first workpiece (12) after the first workpiece (12) has been removed from the stack (16) of further workpieces (18a, 18b).Such a device can advantageously hold the stack of additional workpieces in position during the separation of the first workpiece from the second workpiece. This accelerates the separation process in a mechanically simple and stable manner.

[0019] The sequence direction is understood in particular to mean the direction of the sequence of the workpieces towards the first workpiece, preferably from below.

[0020] The device is preferably designed to carry out a method described here.

[0021] In an advantageous embodiment of the device, the separating layer is designed as a band. The band has a comparatively large surface area, which allows the separating process to be carried out comparatively quickly.

[0022] In another embodiment, the separating layer is formed as a plate-shaped sheet. Such a separating layer is comparatively easy to manufacture.

[0023] By measuring the thickness of the first workpiece lifted, it is possible to check whether only the first workpiece or other workpieces were also lifted inadvertently.

[0024] The features described for the method can be used on the device and vice versa.

[0025] Further advantages of the invention will become apparent from the description and the drawings. Likewise, the above-mentioned and further-described features can be used individually or in combination. The embodiments shown and described are not intended to be exhaustive, but rather serve as examples for describing the invention. Detailed Description of the Invention and Drawings

[0026] Fig. 1 shows schematically a cross section through a device for separating a plate-shaped first workpiece.

[0027] Fig. 2 shows schematically a cross-section through the device, wherein a thickness gauge measures the thickness of the first workpiece.

[0028] Fig. 3 shows schematically a cross-section through the device, wherein a separating layer has been moved under a corner of the first workpiece.

[0029] Fig. 4 shows schematically a section through the device in a horizontal plane.

[0030] Fig. 5 shows schematically a cross section through the device, wherein the first workpiece is removed.

[0031] Fig. 1 schematically shows a cross-section through a device 10 for removing a plate-shaped first workpiece 12 from a top side 14 of a stack 16 of plate-shaped further workpieces 18a, 18b in the sequential direction of the further workpieces 18a, 18b (for reasons of clarity, only the further workpieces 18a, 18b are provided with a reference numeral). The cross-section is shown along a vertical plane through the device 10. In particular, the device 10 serves to separate the first workpiece 12 from a second workpiece 20 from the stack 16 of the further workpieces 18a, 18b, wherein the second workpiece 20 is adjacent to the first workpiece 12. The first workpiece 12 is lifted by a gripper 22 at a corner 23, wherein the gripper 22 has a first suction unit 24a for suctioning the first workpiece 12. As a result, a gap 46 is formed between the raised corner 23 of the first workpiece 12 and the second workpiece 20.

[0032] The gripper 22 is moved by a drive 26 in a support column 28 of the device 10 in the direction of a lifting axis HA of the device 10, parallel to the sequence direction of the additional plate-shaped workpieces 18a, 18b of the stack 16. The lifting axis HA of the device 10 runs in particular in the vertical direction. The drive 26 also displaces a first support arm 30, to which the gripper 22 is attached, whereby the drive 26 also causes the gripper 22 to move perpendicular to the lifting axis HA of the device 10. A thickness gauge 32 for measuring the thickness of the first workpiece 12 after the first workpiece 12 has been removed from the stack 16 of additional workpieces 18a, 18b is also displaceably mounted on the first support arm 30.

[0033] To separate the first workpiece 12 from the second workpiece 20, the device 10 has a separating layer 34, which is preferably oriented perpendicular to the lifting axis HA. The separating layer 34 is moved by a positioning means 36 along the lifting axis HA and perpendicular thereto via a second support arm 38. In Figure 1, the separating layer 34 is in a retracted position.

[0034] After separating the first workpiece 12 from the second workpiece 20, the first workpiece 12 is removed from the stack 16 of further workpieces 18a, 18b by a transport device 40, which has a second and third suction unit 24b, 24c for gripping the first workpiece 12. The transport device 40 is mounted on a third support arm 42 for displacement in the direction of the lifting axis HA of the device 10.

[0035] Fig. 2 shows a cross-section through the device 10, with the thickness gauge 32 extended on a fourth support arm 44 in the direction of the lifting axis HA of the device 10 and moved toward the first workpiece 12. It grips the first workpiece 12 in the direction of the lifting axis HA of the device 10 and measures the thickness of the workpiece 12 in this direction to check whether only the first workpiece 12 has been lifted, as intended.

[0036] Fig. 3 shows a cross-section through the device 10, wherein the separating layer 34 on the second support arm 38 has been retracted into the gap 46 between the raised first workpiece 12 and the second workpiece 20. The separating layer 34 has been moved from its position shown in Fig. 2 by the positioning unit into the gap 46 between the first workpiece 12 and the second workpiece 20. In the extended position shown, the separating layer 34 blocks the second workpiece 20 and thus the stack 16 of the further workpieces 18a, 18b in the direction of the lifting axis HA in order to fix the stack 16 of the further workpieces 18a, 18b in its position for faster separation of the second workpiece 20 from the first workpiece 12.

[0037] Fig. 4 shows a section through the device 10 in a horizontal plane through the support column 28 and the second support arm 38 in the position shown in Fig. 3. The separating layer on the second support arm 38 is indicated by dashed lines and is located under the raised corner 23 of the first workpiece 12. In one possible embodiment of the method, the separating layer 34 is designed to be moved under a separating section 52 of the first workpiece 12, wherein the separating section 52 comprises the corner 23, an adjacent corner 48 and an edge 50 between the corner 23 and the adjacent corner 48.

[0038] Fig. 5 shows a cross-section through the device 10, wherein the transport device 40 has been moved towards the first workpiece 12 by the third support arm 42 along the lifting axis HA of the device 10 in order to remove the first workpiece 12 from the stack 16 of the further workpieces 18a, 18b. For this purpose, the second and third suction units 24b, 24c suck up the first workpiece 12. The separating layer 34 is located in the gap 46 between the first workpiece 12 and the second workpiece 20 in order to facilitate or accelerate the separation of the first and second workpieces 12, 20. The gripper 22 is movable independently of the separating layer 34 and is located on the first support arm 30 in a retracted position in order to allow the transport device 40 better access to the first workpiece 12.

[0039] Taking all the figures of the drawing together, the invention relates to a method for removing a plate-shaped first workpiece 12 from a top side 14 of a stack 16 of plate-shaped further workpieces 18a, 18b in a sequential direction of the further workpieces 18a, 18b. A gripper 22 moves the first workpiece 12 away from a second workpiece 20, wherein the second workpiece 20 is a workpiece from the stack 16 of the further workpieces 18a, 18b that is adjacent to the first workpiece 12. A separating layer 34 is moved into a gap 46 between a raised corner 23 of the first workpiece 12 and the second workpiece 20 and is thereby displaced at least partially over the second workpiece 20. The first workpiece 12 is moved away from the stack 16 of the further workpieces 18a, 18b.

Claims

Claims: A method for removing a plate-shaped first workpiece (12) from a top surface (14) of a stack (16) of plate-shaped further workpieces (18a, 18b) in a sequence direction of the further workpieces (18a, 18b) comprising the steps: a) lifting the first workpiece (12) by a gripper (22); b) inserting a separating layer (34) between a raised corner (23) of the first workpiece (12) and a second workpiece (20) from the stack (16) of further workpieces (18a, 18b), wherein the second workpiece (20) is adjacent to the first workpiece (12); c) holding down the stack (16) of further workpieces (18a, 18b) by the separating layer (34); d) removing the first workpiece (12) from the stack (16) of further workpieces (18a, 18b); e) Measuring the thickness of the first workpiece (12). Method according to claim 1, wherein a gas flows out at least temporarily from at least one nozzle of the separation layer (34). Method according to claim 2, wherein the gas is compressed air.A method according to any one of the preceding claims, wherein suction is at least temporarily provided through a nozzle of the separating layer (34). A method according to any one of the preceding claims, comprising removing the gripper (22) from the first workpiece (12) after inserting the separating layer (34) between the raised corner (23) and the adjacent second workpiece (20). A method according to any one of the preceding claims, comprising shifting and / or pivoting the stack (16) of further workpieces (18a, 18b) after inserting the separating layer (34) between the raised corner (23) and the adjacent second workpiece (20). A method according to any one of the preceding claims, wherein the separating layer (34) is configured as a strip. A method according to any one of the preceding claims, wherein the separating layer (34) is inserted between a separating section (52) of the first workpiece (12), which includes the raised corner (23), and the adjacent second workpiece (20), wherein the separating section (52) comprises the raised corner (23), an adjacent corner (48), and an edge (50) between these corners (23, 48). Device (10) for removing a plate-shaped first workpiece (12) from a top surface (14) of a stack (16) of plate-shaped further workpieces (18a, 18b) in a sequence direction of the further workpieces (18a, 18b),wherein the device for carrying out a method according to any one of claims 1 to 8 is configured, comprising: i) a gripper (22) for gripping the first workpiece (12) with a drive (26) for moving the gripper (22) along a lifting axis (HA) of the device (10); ii) a separating layer (34) oriented perpendicular to the lifting axis (HA), with a positioning means (36) for moving the separating layer (34) along the lifting axis (HA) and perpendicular thereto; iii) a transport device (40) for removing the first workpiece (12) from the stack (16) of further workpieces (18a, 18b); iv) a thickness gauge (32) for measuring the thickness of the first workpiece (12) after the first workpiece (12) has been removed from the stack (16) of further workpieces (18a, 18b). Device according to claim 9, wherein the separating layer (34) is formed as a strip. Device according to claim 9, wherein the separating layer (34) is formed as a sheet in the shape of a plate. Device according to any one of claims 9 to 11, wherein the separating layer has at least one nozzle. Device according to claim 12, wherein the separating layer (34) has several nozzles. Device according to any one of claims 12 or 13, wherein the at least one nozzle is provided on an end face of the separating layer (34).

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