METHOD AND DEVICE FOR SEPARATING WORKPIECES

Abstract

A method for removing a plate-shaped first workpiece from an upper side of a stack of plate-shaped further workpieces in a sequential direction of the further workpieces includes lifting the first workpiece using a gripper, and 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 is adjacent to the first workpiece. The method further includes holding down the stack of further workpieces by the separating layer, removing the first workpiece from the stack of further workpieces, and measuring a thickness of the first workpiece.

Description

FIELD

Embodiments of the present invention relate to a method for removing a plate-shaped first workpiece from an upper side of a stack of plate-shaped further workpieces in a sequential direction of the further workpieces. Embodiments of the present invention also relate to a device for separating workpieces, in particular for carrying out such a method.

BACKGROUND

From DE 11 2012 006 565 T5 a method for separating metal sheets is known in which a metal sheet is lifted from a stack of metal sheet pieces, whereupon a separating element is inserted between the lifted metal sheet and an adjacent metal sheet below the lifted metal sheet. The lifted sheet is then removed from the sheet stack.

The disadvantage is that the adjacent sheet can partially adhere to the lifted sheet and be partially moved along with the lifted sheet when this 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. Measures to improve the separation require additional aids, such as compressed air.

SUMMARY

Embodiments of the present invention provide a method for removing a plate-shaped first workpiece from an upper side of a stack of plate-shaped further workpieces in a sequential direction of the further workpieces. The method includes lifting the first workpiece using a gripper, and 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 is adjacent to the first workpiece. The method further includes holding down the stack of further workpieces by the separating layer, removing the first workpiece from the stack of further workpieces, and measuring a thickness of the first workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

Subject matter of the present disclosure will be described in even greater detail below based on the exemplary figures. All features described and/or illustrated herein can be used alone or combined in different combinations. The features and advantages of various embodiments will become apparent by reading the following detailed description with reference to the attached drawings, which illustrate the following:

FIG. 1 schematically shows a cross section through a device for separating a plate-shaped first workpiece according to some embodiments;

FIG. 2 schematically shows a cross section through the device, wherein a thickness gage measures the thickness of the first workpiece, according to some embodiments;

FIG. 3 schematically shows a cross section through the device, wherein a separating layer has been moved under a corner of the first workpiece, according to some embodiments;

FIG. 4 schematically shows a section through the device in a horizontal plane, according to some embodiments; and

FIG. 5 schematically shows a cross section through the device, wherein the first workpiece is removed, according to some embodiments.

DETAILED DESCRIPTION

Embodiments of the present invention provide a method for separating plate-shaped workpieces which quickly separates the plate-shaped workpieces from one another in a mechanically simple manner. Embodiments of the invention also provide a device for carrying out the method.

The method according to embodiments of the invention includes the following steps:

• • a) lifting the first workpiece using 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 of 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).

By holding down the stack of further workpieces, the separating layer holds the further workpieces in their position, in particular the second workpiece, so that the second workpiece is released from the first workpiece comparatively quickly without changing its position in the process. By holding down the stack of the further workpieces, it is ensured in a mechanically stable manner 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. Preferably, there are no additional aids or contours for separating the first workpiece (such as a nozzle for compressed air) that make gripping the first workpiece more difficult or cause a time delay. Separating a corner is advantageous, among other things, because it allows two adjacent edges of the workpiece to be at least partially separated at the same time, which saves time and money in the method.

The separating layer can have at least one nozzle, in particular a plurality of nozzles. The nozzle(s) may be provided on an end face of the separating layer. During the method, a gas, in particular compressed air, can flow out of the nozzle(s) at least at times. Alternatively, suction through the nozzle(s) can occur.

In step b), the separating layer is moved over at least a part of the second workpiece, which is covered by the separating layer. The term “holding down” is understood in particular to mean that the separating layer blocks a movement of this covered part of the second workpiece in the direction of the first workpiece and/or exerts a force on this part of the second workpiece which is directed away from the first workpiece. The force is directed towards the further workpieces under the second workpiece.

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 portions of its surface.

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

The second workpiece can be guided along the separating layer in order to accelerate the separation of the first workpiece from the second workpiece. The stack can be moved and/or pivoted using a storage trolley.

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

In particular, by measuring the thickness it can be checked whether only the first workpiece or, accidentally, also other workpieces were lifted and/or removed from the stack of further workpieces. The thickness of the first workpiece can be measured before and/or after inserting the separating layer between the first and second workpiece.

In a preferred embodiment of the method, the separating layer is inserted between a separating portion of the first workpiece, which comprises the raised corner, and the adjacent second workpiece, wherein the separating portion comprises the raised corner, an adjacent corner and an edge between these corners. The separation takes place simultaneously across the entire width of the workpieces between two opposite edges of the relevant workpieces, which means that the separation takes place quickly.

A device according to embodiments of the invention for removing a plate-shaped first workpiece from an upper 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 with a drive for moving the gripper along a lifting axis of the device;
  • ii) a separating layer aligned perpendicular to the lifting axis, with 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 the further workpieces;
  • iv) a thickness gage (32) for measuring the thickness of the first workpiece (12) after removing the first workpiece (12) from the stack (16) of further workpieces (18a, 18b).

Advantageously, such a device can be used to hold down the stack of further workpieces in their position during the separation of the first workpiece from the second workpiece. This accelerates the separation process in a mechanically simple and stable manner.

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

The device according to embodiments of the invention is preferably designed to carry out a method described here.

In an advantageous embodiment of the device, the separating layer is designed as a band. The band has a comparatively large surface area, which means that the separation process takes place comparatively quickly.

In a further embodiment, the separating layer is plate-shaped and designed as a metal sheet. Such a separating layer is comparatively easy to produce.

By measuring the thickness of the first workpiece lifted, it is possible to check in particular whether only the first workpiece was lifted or whether further workpieces were accidentally lifted as well.

The features described for the method can be applied to the device and vice versa.

Further advantages of the invention can be found in the description and the drawings. Likewise, the aforementioned features and those which are to be explained below can each be used individually or together in any desired combinations. The embodiments shown and described are not to be understood as an exhaustive list, but, rather, have an exemplary character for the description of the invention.

FIG. 1 schematically shows a cross section through a device 10 for removing a plate-shaped first workpiece 12 from an upper 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 sign). 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.

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 sequential direction of the plate-shaped further 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 a movement of the gripper 22 perpendicular to the lifting axis HA of the device 10. A thickness gage 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 is also movably mounted on the first support arm 30.

To separate the first workpiece 12 from the second workpiece 20, the device 10 has a separating layer 34, which is preferably aligned 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 FIG. 1, the separating layer 34 is in a retracted position.

After separating the first workpiece 12 from the second workpiece 20, the first workpiece 12 is removed from the stack 16 of the 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 so as to be displaceable in the direction of the lifting axis HA of the device 10.

FIG. 2 shows a cross section through the device 10, wherein the thickness gage 32 is extended on a fourth support arm 44 in the direction of the lifting axis HA of the device 10 and moved towards the first workpiece 12. It grasps 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 in order to check whether only the first workpiece 12 has been lifted as intended.

FIG. 3 shows a cross section through the device 10, wherein the separating layer 34 on the second support arm 38 is retracted into the gap 46 between the raised first workpiece 12 and the second workpiece 20. The separating layer 34 was 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.

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 portion 52 of the first workpiece 12, wherein the separating portion 52 comprises the corner 23, an adjacent corner 48 and an edge 50 between the corner 23 and the adjacent corner 48.

FIG. 5 shows a cross section through the device 10, wherein the transport device 40 has been moved by the third support arm 42 along the lifting axis HA of the device 10 to the first workpiece 12 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 pick up the first workpiece 12 by suction. 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.

In a combined view of all the figures of the drawing, embodiments of the invention relate to a method for removing a plate-shaped first workpiece 12 from an upper 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 in the process is at least partially displaced over the second workpiece 20. The first workpiece 12 is moved away from the stack 16 of the further workpieces 18a, 18b.

While subject matter of the present disclosure has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. Any statement made herein characterizing the invention is also to be considered illustrative or exemplary and not restrictive as the invention is defined by the claims. It will be understood that changes and modifications may be made, by those of ordinary skill in the art, within the scope of the following claims, which may include any combination of features from different embodiments described above.

The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B. or the entire list of elements A. B and C.

Claims

1. A method for removing a plate-shaped first workpiece from an upper side of a stack of plate-shaped further workpieces in a sequential direction of the further workpieces, the method comprising: lifting the first workpiece using a gripper;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;holding down the stack of further workpieces by the separating layer;removing the first workpiece from the stack of further workpieces; ande) measuring a thickness of the first workpiece.

2. The method according to claim 1, wherein at least at times a gas flows out of at least one nozzle of the separating layer.

3. The method according to claim 2, wherein the gas is compressed air.

4. The method according to claim 1, wherein at least at times suction occurs through a nozzle of the separating layer.

5. The method according to claim 1, further comprising removing the gripper from the first workpiece after the insertion of the separating layer between the raised corner and the adjacent second workpiece.

6. The method according to claim 1, further comprising displacing and/or pivoting the stack of further workpieces after the insertion of the separating layer between the raised corner and the adjacent second workpiece.

7. The method according to claim 1, wherein the separating layer is formed as a band.

8. The method according to claim 1, wherein the separating layer is inserted between a separating portion of the first workpiece comprising the raised corner and the adjacent second workpiece, the separating portion comprising the raised corner, an adjacent corner, and an edge between the raised corner and the adjacent corner.

9. A device for removing a plate-shaped first workpiece from an upper side of a stack of plate-shaped further workpieces in a sequential direction of the further workpieces, wherein the device is configured to carry out a method according to claim 1, the device comprising: a gripper for gripping the first workpiece with a drive for moving the gripper along a lifting axis of the device;a separating layer aligned perpendicular to the lifting axis, with a positioner for moving the separating layer along the lifting axis and perpendicular thereto;a transport device for removing the first workpiece from the stack of further workpieces; anda thickness gage for measuring the thickness of the first workpiece after removing the first workpiece from the stack of further workpieces.

10. The device according to claim 9, wherein the separating layer is configured as a band.

11. The device according to claim 9, wherein the separating layer is configured as a metal sheet.

12. The device according to claim 9, wherein the separating layer comprises at least one nozzle.

13. The device according to claim 12, wherein the separating layer comprises a plurality of nozzles.

14. The device according to claim 12, wherein the at least one nozzle is provided on an end face of the separating layer.