TWI405703B - This glass gripper - Google Patents

Abstract

A thin-glass gripper is described for holding and turning a flat workpiece (1), comprising a plurality of gripper arms (2a-h) having at least one suction lifter (3a-n) arranged in each case on them, wherein the gripper arms (2a-h) can be connected via a common connecting flange (4) to a handling and transferring device (19) and the suction lifters (3a-n) can be connected to a vacuum line (5). The gripper arms (2a-h) of the thin-glass gripper are oriented radially with regard to the connecting flange (4) and are telescopic in their axial direction.

Description

Thin glass holder

The present invention relates to a thin glass holder for holding and moving a planar workpiece, comprising a plurality of holder arms, each holder arm having at least one suction cup disposed thereon, the clamping The arms can be coupled to a handling and transfer member via a common attachment flange and the suction cups can be coupled to a vacuum line.

In addition to the conveyor belt, a thin glass holder, also known as a vacuum chuck, is an essential component of the conveyor chain in the manufacture of thin-walled glass sheets. These thin glass holders operate at a reduced pressure of one of 0.3 bar to 1.0 bar and are fitted to a handling and transfer member (especially an industrial robot) capable of space movement.

In the manufacture of thin glass, the demand for transportation of larger glass sheets is gradually increasing. In addition, the thickness of the thin glass has been further reduced for certain applications such that when using known thin glass holders, the load limit of the thin glass is gradually exceeded and significant losses are incurred during shipping. Another drawback consists of the fact that in an established conveyor chain utilizing previously known thin glass holders, there is only limited flexibility for the transport of glass sheets of different sizes.

Accordingly, it is an object of the present invention to provide a thin glass sheet holder that allows for careful handling of glass sheets of various sizes.

According to the invention, this object is achieved by a thin glass holder, wherein the holder arms are radially oriented with respect to the connecting flange and are telescopic in their axial direction.

A connecting flange is used to secure the thin glass holder to the handling and transfer member. In addition, the thin glass holder is connected to a vacuum line that is connected to all of the suction cups via a separate line from it.

Due to the radial positioning of the gripper arms, the suction cups can be distributed as evenly as possible relative to the thin glass surface. The axial adjustability ensures the flexibility of the thin glass holder for different sizes of glass sheets while maintaining an even distribution of the suction cups. During this process, the distance between the suction cups can only be increased evenly, so that even with a large thin glass surface area, a substantially constant load can be maintained. It should be constantly adjusted.

For telescoping adjustment of the gripper arms, the gripper arms preferably each include an outer tube and an inner tube displaceable in the outer tube. According to a first advantageous embodiment, the inner tube can be manually adjusted relative to the outer tube. This can occur, for example, by unscrewing a fastening screw and then pulling the inner tube out. In one end position, the fastening screw can be manually tightened again.

Alternatively, the inner tube can also be displaced relative to the outer tube by means of an actuating motor, each holder having its own actuating motor and being actuated by its own actuating motor. The adjustment of the actuating motor allows the position of the suction cup to be moved particularly flexibly and can therefore be set for differently sized glass sheets.

It has proven to be advantageous to have the gripper arms form an identical angle to one another in the circumferential direction. If the inner tubes are in the same extended state, this configuration enables the suction cups to be evenly distributed with respect to each other and thus enables a uniformly distributed force to be supplied to the thin glass sheet to be transported.

In a particular embodiment, in each case, at least one suction cup is disposed at the outer ends of the holder arms, the suction cups drawing a rectangular region therebetween, that is, all of the inner tubes extend identically. This is reasonable, especially when it is necessary to lift a rectangular glass sheet with the thin glass holder.

Preferably, the gripper arms employ a polygonal profile, and particularly preferably a substantially DIN 32712 (P4C) profile with rounded edges. This profile consists essentially of a ring with four cycloidal stretch sides. This profile section allows the inner tube to be easily and quickly adjusted relative to the fixed outer tube even under load. Furthermore, this profile makes it possible to transmit the increased torque in a compact size, so that the suction cups can be fitted to the gripper arms with a very high level of torsion resistance. Due to the polygonal profile, no stress concentration occurs between the inner tube and the outer tube and there is only a very small range of motion, thus avoiding the offset of the inner tube. The polygonal profile includes a large hollow interior space that provides space for, for example, a linear drive or a pipeline for providing compressed air, vacuum, or current.

The gripper arms are preferably made of carbon. This results in a significant reduction in the dead weight of the holder relative to an aluminum construction of about 50%. In this way, the entire production cycle can be performed faster because the thin glass holder operates at a relatively high rate of rotation. This carbon construction is particularly suitable for producing the polygonal profile described above. First, a basic polygonal axis is produced which is relatively preferably manufactured up to 1000 mm. The outer tube is created by covering the base polygonal shaft, and the inner tube is created by lining the inside of the outer tube. Therefore, this shaft/shell connection is produced with only one tool, with a very good fit and a length longer than 1000 mm. In addition to obtaining the basic polygonal shaft at one time, the guide member is also inexpensive to manufacture.

Preferably, eight holder arms are disposed on the attachment flange, each of the holder arms alternately exhibiting an angle of 41° on one side of one arm and 50 on the other side of the arm ° angle. This creates a close spacing of the suction cups, wherein a relatively small load is created on the thin glass, which is especially necessary for the transport of thin-walled glass sheets, such as touch screens.

It has also proven to be advantageous if a suction cup is arranged on the outer tube on the four holder arms which are arranged as diameters with respect to the connecting flange, and a suction cup is arranged on the inner tube.

In each of the two holder arms arranged as a diameter relative to the connecting flange, in each case the inner tube can comprise at its end a fixing bracket with two suction cups oriented transversely to the inner tube. In addition, two other gripper arms are provided as diameters, each of which is provided with a suction cup at the end. The latter two gripper arms are alternately located between the previous gripper arms.

Preferably, a plurality of suction cups are gathered in the absorption area and the reduced pressure can be individually applied thereto. This is beneficial because a large number of individual panels in the stack are prevented from spreading at the lower edge, especially when the thin glass sheet is lowered. Otherwise the plates slide during transport and are thereby damaged.

In a preferred development, at least one distance sensor is disposed on the thin glass holder, and in particular two distance sensors are preferably disposed. The distance sensors are used to detect the distance from the thin glass sheet and assist in position detection and position control, thereby achieving a particularly precise positioning at the desired location on the thin glass sheet. This also helps to handle it carefully.

To improve stability, the gripper arms can be attached to a centrally mounted mounting plate. In this way, the retaining arms can also be aligned with one another in a plane.

Figure 1 is a perspective side view of a thin glass holder centrally provided with a connecting flange 4 for attaching the thin glass holder to a robotic arm 19 (see Figure 3).

A total of eight gripper arms 2a-h extend radially outward from the connecting flange 4, which form a common midpoint. At the lower portion, the gripper arms 2a-h each include at least one disc-shaped suction cup 3a-n disposed at the end thereof. In order to rise steadily, the gripper arms 2a-h are attached with their upper side to a common mounting plate 11.

The structural embodiment of the individual gripper arms 2a-h is particularly easy to see in Figure 2. Figure 2 shows a bottom view of a thin glass holder that rotates about the axis of rotation 20 (see Figure 1) in the direction of the arrow. The holder arms 2a-h have a two-part construction and include a fixed outer tube 6 extending to the attachment flange 4 and an inner tube 7 having a smaller diameter that is guided to be displaced in the outer tube 6. . Here the outer tube 6 projects beyond the mounting plate 11, and in the illustration of Figures 1 and 2, the inner tube 7 is located in an extended position and thus enables the transport or handling of large thin glass sheets.

A total of four gripper arms 2a, 2c, 2e, 2g are identically provided with suction cups 3a, 3b, 3d, 3e, 3i, 3h, 3k, 3l, in each case a suction cup 3b, 3d, 3h, 3k are fixedly disposed on the outer tube 6 with respect to the connecting flange 4, and in each case, a suction cup 3a, 3e, 3i, 31 is fixedly disposed at the outer end of the inner tube 7. Two of the four gripper arms 2a, 2c, 2e, 2g are opposed to each other with respect to the connecting flange as a diameter.

The holder arms 2b, 2f opposite each other comprise in each case a single suction cup 3c, 3j at the outer end of the inner tube 7. No additional suction cups are provided on the respective outer tubes 6 of the gripper arms 2b, 2f.

Positioning the other mutually opposite gripper arms 2d, 2h between the gripper arms 2a and 2g and the gripper arms 2c and 2e, in each case the adjustable inner tube 7 of the gripper arm is at its end The fixing brackets 9a, 9b oriented transversely to the axial extension of the inner tube 7 are carried. The suction cups 3f, 3g are engaged with the fixing bracket 9a at their ends, and the suction cups 3m, 3n are engaged with the fixing bracket 9b at their ends, whereby the free distance between the suction cups 3a and 3l and the suction cups 3e and 3i is greatly reduced, and The thin glass plate to be transported is provided with additional support.

It is also apparent from the bottom view of Fig. 2 that the suction cups 3a, 3e, 3i, 3l draw a rectangle, and the other outer suction cups 3c, 3f, 3g, 3j, 3m, 3n are aligned therewith.

A distance sensor 10 is inserted into one of the holes of the mounting plate 11 , and the distance sensor can detect the distance between the thin glass holder and a workpiece 1 (see FIG. 3 ). The thin glass holder is stopped particularly accurately on the workpiece.

Figure 3 shows a side view of a thin glass holder mounted to the robot arm 19 by means of its centrally connected connecting flange 4. Only the gripper arms 2c, 2d, 2e and their suction cups 3e, 3f, 3g, 3i can be seen in this view. The suction cups 3e, 3f, 3g, 3i are in contact with the workpiece 1 in the form of a thin glass plate at its lower portion. The reduced pressure necessary to hold the workpiece 1 is transmitted via a vacuum line 5 to the thin glass holder. In the region of the connecting flange 4, the bundled vacuum lines 5 are separated, their individual lines being connected to the gripper arms 2a-h and thereby to the respective suction cups 3a-n, for example from the gripper arms The dotted line of 2e can be seen. By means of the independent connection of the suction cups 3a-n, the suction cups 3a-n can jointly apply an adjustable reduced pressure to them or release them individually or in groups.

The side view of Figure 3 also clearly shows that the outer tube 6 and the inner tube 7 have a generally square cross section with an arcuate side and a rounded corner.

Figure 4a is a perspective view of the gripper arms 2b, 2f. It can be attached to the mounting plate 11 by means of an inner lower strap 12 and an outer lower strap 13 (see Figures 1-3). A fastening screw 15 is arranged at the outer end of the outer tube 6, the bottom end of which extends through the outer tube 6 as far as the inner tube 7. The fastening screw 15 is threadedly engaged in a complementary cut thread in a base 21 which is a one-piece part of the upper portion 16 of the ring. The collar upper portion 16 is in turn engaged with a flange-type fastening portion 22 on the outer tube 6 from the bottom applied lower portion 17 of the collar and is coupled to the lower portion of the collar via at least one fastening portion 22 Form a continuous assembly. If the fastening screw 15 is unscrewed, it cannot be effectively engaged with the inner tube 7, so that the inner tube 7 may be displaced in the axial direction with respect to the outer tube 6. In order to fasten the inner tube 7 to the outer tube 6, the fastening screw 15 is again tightened.

The suction cups 3a-n are attached to the respective inner tubes 7 by means of an upper strap 14. This can be seen by the examples according to the suction cups 3c, 3j. A connector 18 is positioned on top of the suction cups 3a-n to which individual lines of the vacuum line 5 can be attached.

Figure 4b shows a longitudinal section of the gripper arms 2b, 2f with the inner tube 7 in a retracted position relative to the outer tube 6. However, the inner tube 7 is not manually displaced, but by means of a servo motor 8. For this purpose, the fastening screw 15 is removed and, alternatively, the actuating motor 8 (preferably a stationary cylinder) is disposed on the gripper arms 2b, 2f. The actuation motor interacts with a first end on the outer tube 6 and a second end on the inner tube 7, wherein the first end can be mated to, for example, the substrate 21. Since the outer tube 6 of all the holder arms 2a-h of the thin glass holder has the same structure as the inner tube 7, it is particularly simple to provide the actuator motor 8 for each holder arm 2a-h.

Figure 5 illustrates an embodiment of the gripper arms 2d, 2h with a fixed bracket 9a, 9b attached to the end of the gripper arm by an upper strap 14 transversely to the axial extension of the inner tube 7. Two connecting members 18 project from the fixing brackets 9a, 9b as an extension of the inner tube 7, providing a first connecting member 18 for connecting a connecting wire (not shown) to the suction cups 3f, 3n, and providing a second connecting member 18 for connecting another connection line (also not shown) to the suction cups 3g, 3m.

1. . . Workpiece

2a-h. . . Holder arm

3a-n. . . Suction cup

4. . . Connecting flange

5. . . Vacuum line

6. . . External tube

7. . . Internal tube

8. . . Actuating motor

9a, 9b. . . Fixed bracket

10. . . Distance sensor

11. . . Mounting plate

12. . . Under the strap, inside

13. . . Bottom strap, outside

14. . . Upper strap

15. . . Fastening screw

16. . . Upper part of the collar

17. . . Lower part of the collar

18. . . Connector

19. . . Handling and transferring components, robot arm

20. . . Rotation axis

twenty one. . . Base

twenty two. . . Flange type fastening part

Figure 1 is a perspective plan view of a thin glass holder; Figure 2 is a bottom view of a thin glass holder; Figure 3 is a side view of a thin glass holder; Figure 4a is a holder having a suction cup disposed thereon A perspective plan view of the arm; Figure 4b shows a longitudinal cross-sectional view of the holder arm with the actuation motor; and Figure 5 is a perspective plan view of the holder arm with the fixed bracket and the two suction cups disposed thereon.

2a-h. . . Holder arm

3a-n. . . Suction cup

4. . . Connecting flange

9a, 9b. . . Fixed bracket

11. . . Mounting plate

19. . . Robot arm

20. . . Rotation axis

Claims (15)

A thin glass holder for holding and moving a planar workpiece (1), comprising a plurality of holder arms (2a-h), each holder arm having at least one suction cup disposed thereon ( 3a-n), the holder arms (2a-h) are connectable to a handling and transfer member (19) via a common attachment flange (4), and the suction cups (3a-n) are connectable to one A vacuum line (5), characterized in that the holder arms (2a-h) are radially oriented with respect to the connecting flange (4) and are telescopic in their axial direction. A holder according to claim 1, characterized in that the holder arms (2a-h) each comprise an outer tube (6) and an inner tube displaceable in the outer tube (6) (7). A holder according to claim 2, characterized in that the inner tube (7) is manually adjustable relative to the outer tube (6). A holder according to claim 2, characterized in that the inner tube (7) is adjustable relative to the outer tube (6) by means of an actuating motor (8). A holder according to any one of claims 1 to 4, characterized in that the holder arms (2a-h) form an identical angle with each other in a circumferential direction. A holder according to any one of claims 1 to 4, characterized in that in each case at least one suction cup (3a, 3c, 3e, 3f, 3g, 3i, 3j, 3l, 3m, 3n) is configured At the outer ends of the holder arms (2a-h), the suction cups (3a, 3c, 3e, 3f, 3g, 3i, 3j, 3l, 3m, 3n) draw a rectangular area therebetween. A holder according to any one of claims 1 to 4, characterized in that the holder arms (2a-h) adopt a polygonal contour. A holder according to any one of claims 1 to 4, characterized in that the holder arms (2a-h) are made of carbon. A holder according to any one of claims 1 to 4, characterized in that eight holder arms (2a-h) are disposed on the attachment flange (4), each of the holder arms Alternately, an angle of 41° is displayed on one side of one arm and an angle of 50° is displayed on the other side of the arm. A holder according to claim 9, characterized in that, in each of the four holder arms (2a, 2c, 2e, 2g) configured as a diameter, in each case, a suction cup (3b, 3d, 3h, 3k) is disposed on the outer tube (6), and in each case, a suction cup (3a, 3e, 3i, 31) is disposed on the inner tube (7). A holder according to claim 9, characterized in that in two holder arms (2d, 2h) configured as diameters, in each case, the inner tube (7) comprises at its end a A laterally oriented fixing bracket (9a, 9b) of two suction cups (3f, 3g, 3m, 3n). A holder according to any one of claims 1 to 4, characterized in that a plurality of suction cups (3a-n) are gathered in the absorption area and a reduced pressure can be individually applied thereto. A holder according to any one of claims 1 to 4, characterized in that at least one distance sensor (10) is disposed on the thin glass holder. A holder according to any one of claims 1 to 4, characterized in that the holder arms (2a-h) are attached to a centrally disposed mounting plate (11). A holder according to claim 1, characterized in that the holder arms (2a-h) each comprise an outer tube (6) and a displacement in the outer tube (6) The inner tube (7), wherein the outer tube (6) and the inner tube (7) adopt a polygonal contour and wherein the polygonal contour consists of a ring having four cycloidal stretching sides.