DE29705258U1 - Tape sticking device - Google Patents

Description

AAl DE-G 297 05 258.6

Applicant: KUKA Welding Systems File: 772-839 er/ha Date: 18.06.1998 5

DESCRIPTION

Tape application device

The invention relates to a manipulator-guided tape application device for adhesive tapes with the features in the preamble of the main claim.

Such a tape application device is known from DE-C 43 10 146. It consists of a rotating tape reel, a tape guide device and an application device that applies the adhesive tape to the workpiece, in particular a vehicle body. The tape reel is mounted so that it can rotate freely. The adhesive tape is pulled off the workpiece by the application device and the feed of the tape application device. There is only a tape brake to prevent the tape reel from running on when the feed stops. In practice, it has been shown that this design of the tape application device is not sufficiently reliable and results in limitations in the production speed.

EP-A-O 325 855 shows another adhesive tape application device with a tape reel, which also has a motor. However, this motor works against the pulling direction and is intended to tighten the pulled adhesive tape in the manner of a tape brake. The application device is arranged stationary and works together with a moving conveyor belt.

DE-C-36 14 365 shows a robot-guided adhesive tape application device. An air motor is assigned to the rotating tape reel. This should also work against the pull-off direction and tighten the adhesive tape.

Another robot-guided adhesive tape application device is known from DE-A-36 07 418. This device has a drive for a carrier tape, which is used to pull the carrier tape off the adhesive tape. The adhesive tape is applied by the feed movement of the robot. The tape reel is not driven.

US-A-4,978,417 discloses a laminating device with which non-adhesive fiber tapes are applied to a mold, whereby a multi-layer molded product is to be created by applying several layers one on top of the other. The fiber tapes are combined with an adhesive carrier tape and an even more adhesive take-off tape. The fiber tape is cut into the desired partial shapes before application, whereby the unnecessary fiber tape parts are removed via the take-off tape. The take-off tape and the carrier tape are wound up via motor-driven reels after the fiber tape has been removed.

The invention is based on the object of providing an improved tape application device.

The invention solves this problem with the features in the main claim.

According to the invention, the tape reel is now additionally and independently driven in the pull-off direction. This relieves the adhesive tape of the pull-off forces and the tensions that occur during this process, which significantly increases operational safety and reliably prevents the adhesive tape from tearing. In addition, the production and application speeds can be significantly increased.

increase.

In a particularly favorable embodiment, the winding drive is controlled in a suitable manner according to the production conditions, which is preferably done via a control connection to the manipulator or based on the existing belt tension. The belt tension can thus always be kept at an optimal value regardless of the production speed, with the speed of the winding drive being adapted and adjusted accordingly to the production conditions.

The winding drive advantageously acts on the outer circumference of the tape roll. It therefore automatically compensates for changes in the thickness of the tape roll. This design is also particularly practical and reliable. A friction drive with drive rollers is preferably used, which can compensate for irregularities and operational faults, e.g. winding blockages.

There are various options for the design of the tape tension control device. In the preferred and particularly practical embodiment, the tape tension tester consists of a movable tension roller for the adhesive tape and a position indicator that determines the tension roller position dependent on the tape tension and thereby indirectly checks the adhesive tape tension. The tension roller can also be used to guide the adhesive tape in a suitable manner.

Further advantageous embodiments of the invention are specified in the subclaims.

The invention is illustrated by way of example and schematically in the drawings. In detail:

Figure 1: The tape application device in side view,

Figure 2: a front view of the device according to arrow II of Figure 1,

Figure 3: a top view of the application device according to arrow III of Figure 2,

Figure 4: a side view of the application device according to

Arrow IV of Figure 3 and
15

Figure 5: a front view of the application device according to arrow V of Figure 3.

The invention relates to a tape application device (1) which is guided by a manipulator (2), in particular a multi-axis industrial robot. The device is used to apply an adhesive tape (7) to a workpiece (45). This is preferably a vehicle body, in particular a body shell. The adhesive tape is used, for example, to cover fastening surfaces for the adhesive bead to be applied later on a vehicle window. The body shell can then be surface-treated and in particular painted, with the adhesive tape covering and protecting the subsequent bead area.

The tape application device (1) consists of a tape guide device (3) and an application device (27) with which the adhesive tape (7) is applied to the workpiece (45). The tape application device (1) has a frame (4) with which it is flanged to the robot hand (2) and rotated around the hand axis (47) and

if necessary - can be moved around other hand axes (not shown). The tape application device (1) is moved by the robot (2) along the working direction (46) over the workpiece (45) and is pressed onto the workpiece (45) in the direction of the hand axis (47) using a pressure roller (35) described below.

The tape guide device (3) includes a driven rotatable tape reel (5) from which the

&iacgr;&ogr; adhesive tape (7) is removed. With a control connection to the manipulator (2) and/or a

The tape tension is controlled by the tape tension control device (1.6) and the winding drive (9) is controlled or regulated. The removal of the adhesive tape (7) from the tape roll

(5) is carried out on the one hand by sticking and fixing the adhesive tape (7) on the workpiece (45) and guiding the tape application device (1) in the working direction (46). The pull-off is supported by the winding drive (9) described below and preferably additionally controlled.

The application device (27) also includes a separating device (36) for separating, in particular cutting off, the tape end section (44) of the adhesive tape (7).

Figures 1 and 2 show the tape application device 1 in a side view and a front view. The tape application device (1) has a winding drive

(9) which actively drives the tape roll (5) when the adhesive tape (7) is pulled off. The winding drive (9) has one or more drive rollers (10) which act on the outer circumference of the tape roll (5) and cause it to rotate around the winding axis (8) in the pulling direction by means of frictional force. The tape roll (5) is driven at a speed which is largely independent of the winding diameter. The winding drive (9) also has a controllable

· t 4

Roller drive (11), which e.g. has a controllable DC motor with a suitable gear.

The winding drive (9) has a feed device (13) shown in more detail in Figure 1 for positioning it on the tape roll (5). The drive rollers (10) and the roller drive (11) are arranged on a swivel arm (14) which is rotatably mounted on the frame (4) of the tape gluing device (1). The support roller (6) for the tape roll (5) is also rotatably mounted on the frame (4). The bearing point for the swivel arm (14) is located at a distance next to the tape roll (5).

The feed device (13) also includes a suitable elastic feed element (15) with a preferably flat characteristic curve, e.g. a gas spring, which is hinged to the frame on one side and is connected to the swivel arm (14) on the other side. Alternatively, it can also be a controlled pneumatic cylinder. The feed element (15) rotates the swivel arm (14) and presses the drive rollers (10) with an essentially constant force against the outer circumference of the tape roll (5).

The winding drive (9) can have a warning device (49) for signaling the end of the tape or winding in good time. It consists, for example, of a switch flag (49) arranged on the moving roller drive (11), which interacts with one or more switches (50, 51) on the tape winding (5). These are positioned at different distances in the range of motion of the switch flag (49) depending on the winding thickness and signal an advance warning (50) and the end of the tape (51) and cause a manipulator stop.

The winding drive (9) can be controlled in different ways. In the first variant, there is a control connection to the manipulator (2) or its control system. The manipulator (2) reports the

· I

Web speed at which the tape application device (1) is moved in the working direction (46) to the control (12) of the winding drive (9). The winding drive (9) then rotates the tape roll (5) accordingly in order to pull off the adhesive tape (7) preferably at the same speed as the web feed. The tape tension fluctuations are compensated by a spring-loaded dancer (17) explained below.

In the second variant, the winding drive (9) is controlled by the tape tension control device (16) mentioned above depending on the tension of the adhesive tape (7). The tape tension control device (16) has a suitable tape tension tester (21) which is connected to the winding drive (9) via the control (12). The tape tension tester (21) can be designed in any suitable manner. The control (12) has a controller (48) for adjusting the speed of the winding drive (9) to a constant tape tension.

In this second case, for example, there is no control connection to the manipulator (2). The manipulator (2) brings the tape gluing device (1) into the start position and begins gluing and feeding the web in the working direction (46). The winding drive (9) does not yet have a control signal at this point and is at a standstill. The tape tension increases in the adhesive tape (7) that is pulled off by the feed movement, which the tape tension tester (21) detects and sends a corresponding start signal to the winding drive (9). The speed of the winding drive (9) is then also controlled or regulated via the additional tape tension monitoring.

In the embodiment shown in more detail in Figure 1, the belt tension tester (21) consists of the aforementioned dancer (17), which in the second variant shown, however, has an additional function. It has a movable

· a

Tension roller (17) over which the adhesive tape (7) is guided coming from the tape roll (5). The tension roller (17) is mounted on a swivel arm (19) which is preferably mounted on the frame (4) on the same axis as the roll axis (8).

A suitable elastic feed device (18) is engaged on the swivel arm (19), which consists, for example, of a gas spring (20) fixed to the frame or another feed device with a flat characteristic curve. Alternatively, it can also be a controlled pneumatic cylinder. The force of the feed device (18) is aligned with the normal strip tension and counteracts it. The forces cancel each other out in the normal dancer position, with the swivel arm (19) assuming the normal operating position shown in Figure 1. In Figure 2, the feed device (18) is not shown for the sake of clarity. If necessary, a counterweight is present at the other end of the arm, which can also be the case with the swivel arm (14) of the winding drive (9).

The belt tension tester (21) also has a position indicator (22) with which the belt tension-dependent tension roller position is determined. The position indicator (22) has a reflector (24) at the rear end of the swivel arm (19), which interacts with a distance sensor (23) fixed to the frame. A rotary movement of the swivel arm (19) and the tension roller (17) results in a change in the distance of the reflector (24) from the sensor (23). Figure 1 shows the normal operating position with solid lines and a dashed representation of a tension roller position with increased belt tension. In this position, the distance sensor (24) is further away from the sensor (23) than normal.

The distance sensor (23) is connected to the control (12) and the regulator (48). For the operating position of the tension roller (17) corresponding to the normal belt tension,

a target value for the reflector distance is determined empirically in advance. If the reflector distance increases above a specified target value, the winding drive (9) is accelerated to correct the increased tape tension until the tension roller (17) returns to its specified position and the reflector (24) returns to its specified distance from the sensor (23). Conversely, if the reflector distance is reduced, the tape winding (9) is braked. In special cases, the winding drive (9) can also rotate backwards, for example to tighten the adhesive tape (7) if it is slack or similar.

Figure 3-5 shows the application device (27) with the separating device (36) in more detail. The adhesive tape (7) pulled off the tape roll (5) is guided via the movable tension roller (17) and a frame-fixed, upper deflection roller (25) to the application device (27) located below and is guided here via another freely rotating deflection roller (26) with a backstop in the feed direction.

The application device (27) is designed in some parts similarly to DE-A-43 10 146. It is elastically mounted on the frame (4) via a suitable adjustment device (28) and can, for example, give way vertically and, if necessary, horizontally via a slide guide. It thus compensates for path deviations of the robot (2) and unevenness of the workpiece (45).

The application device (27) has a channel-like tape guide (29) which extends essentially horizontally and transversely to the working or movement direction (4 6) of the tape application device (1) and is connected to the return roller (26) at the back. The adhesive tape (7) is guided via the tape guide (29) to a tape deflection (30) which is preferably inclined at 45° and with which the adhesive tape (7) can be turned by 90° in the

The tape is deflected in the direction of travel and is also turned in the process. The adhesive surface at the top in the tape guide (29) therefore comes to lie at the bottom.

Shortly after the tape deflection (30), the adhesive tape (7) is held in a clamping device (31). In the preferred embodiment, the clamping device (31) consists of two clamping rollers (32) arranged one above the other, freely rotatable in the feed direction, with a backstop and

&iacgr;&ogr; smooth-walled casings that are arranged closely spaced and clamp the adhesive tape (7) between them. Alternatively, the upper clamping roller can also be a stationary sliding shoe.

As Figure 5 shows, the adhesive tape (7) is guided diagonally downwards to the workpiece (45) after the clamping rollers (32) and moves against the working direction (46). The adhesive tape (7) in this area is referred to as the tape end section (44).

The application device (27) has two freely rotating rollers (33, 35) located behind the clamping device (31) in the direction of tape travel, which are arranged at a distance from one another. The first pressure roller (33) is arranged so that it can be adjusted in height and has, for example, a swivel drive (34). In the operating position shown in Figure 5 with solid lines, the pressure roller (33) is raised so that the tape end section (44) can run unhindered under the roller (33). In the pressing position shown in dashed lines, the pressure roller (33) is lowered and presses the tape end section (44) onto the workpiece (45) in the manner described below.

The downstream pressure roller (35) is stationary and is located at a distance below the clamping device (31). It presses the strip end section (44) onto the workpiece (45). The separating device (36) acts

on the tape end section (44) between the two rollers (33,35). It cuts off the tape end section (44) at the end of the adhesive tape application.

As Figures 3 and 5 illustrate, the separating device

(36) is mounted stationary on the application device (27). It has a pivotable or movable separating knife (37) with a stationary blade. The separating knife (37) is guided by a feed device (39)

&iacgr;&ogr; moves.

In the preferred embodiment, the feed device (39) consists of a swivel arm (40) which extends transversely to the working direction (46) and is actuated by a drive (41). The swivel arm (40) protrudes between the two rollers (33, 35) and carries out a lifting and lowering movement. The swivel arm position and thus the cutting process can be controlled by means of one or more position sensors (42).

In the preferred embodiment, the separating knife has

(37) on the blade or cutting edge a prong profile (38) (see Figure 3). As Figure 5 shows, the cutting knife (37) is set with its surface at an angle to the strip end section (41). The angular position is selected so that the angle of attack (43) between the surfaces of the cutting knife (37) and the strip end section (44) viewed in the working direction (46) and pointing towards the pressure roller (35) is less than 90°. The cutting edge or blade can extend essentially horizontally and parallel to the surface of the strip end section (44). It can also be arranged at an angle to it for a pulling cut.

With the angle of attack shown (43), the cutting knife (37) exerts a tensile force component on the belt end section (44) in the working direction (4 6) during the cutting process.

The tape end section (44) is held between the pressure roller (35) and the workpiece (45) and supports the tensile force. Figure 5 shows the cutting position. During the cutting process, this effectively prevents the adhesive tape from being pulled back from the roll (5). The adhesive tape

(7) can be cut off while driving.

After the tape end section (44) has been cut, the loose end of the supplied adhesive tape (7) hangs down from the clamping device (31). The other end is pressed against the workpiece (45) by the pressure roller (35) during further movement in the working direction (46).

For the next application process, the application device (27) is brought into position above the workpiece (45). The loosely hanging free tape end section (44) is then taken along by the lowered pressure roller (33) and pressed against the workpiece (45). Figure 5 shows this lowered position of the pressure roller (33) in dashed lines. The tape gluing device (1) is moved in the working direction (4 6). As soon as the glued tape end section (44) gets under the pressure roller (35), the pressure roller is moved upwards again. The tape end section (44) is then guided directly from the clamping device (31) to the pressure roller (35).

Modifications to the embodiment shown are possible in various ways. The winding drive (9) can be modified structurally. This also applies to its drive function. For example, it can be made from a

(8) attached drive. The belt tension control device (16) and the belt tension tester (21) are also variable and can consist, for example, of a loop guide with a longitudinally movable tension roller (17). The application device (27) and the separating device (36) can also be designed

be modified,

LIST OF REFERENCE SYMBOLS

1 tape application device

2 Manipulator, robot hand 3 Belt guide device

4 Frame

5 tape wraps

6 Support roller

7 Adhesive tape &iacgr;&ogr; 8 Winding axis

9 Winding drive

10 drive roller

11 Roller drive

12 Control

13 Delivery device

14 Swivel arm

15 Feeding element, gas spring

16 Belt tension control device

17 Tension roller, dancer 18 Feed device

19 Swivel arm

20 Feeding device, gas spring

21 Belt tension tester

22 Position indicator 23 Distance sensor

24 Reflector

25 Deflection pulley 2 6 Deflection pulley

27 Application device

28 Adjustment device, slide

29 Belt guide

30 Belt deflection

31 Clamping device

32 Clamping rollers 33 Pressure roller

34 Swivel drive

35 Pressure roller

36 Separator

37 cutting blades

38 tines

39 Feed device 40 Swivel arm

41 Drive

42 Position sensor

43 Angle of attack

44 End section

45 Workpiece, body

46 Working direction, direction of movement

47 Hand axis

48 controllers

4 9 Warning device, switch flag

50 switches, advance warning

51 Switch, end of tape

Claims (15)

PROTECTION CLAIMS 1.) Manipulator-guided tape application device for adhesive tapes, consisting of a rotating tape reel, a tape guide device and an applying device that applies the adhesive tape to the workpiece, whereby the adhesive tape is removed from the tape reel by the web feed of the tape application device and the bonding to the workpiece &iacgr;&ogr; is pulled off, characterized in that the tape gluing device (1) additionally has a winding drive (9) operating in the pulling direction. 2.) Tape gluing device according to claim 1, characterized in that the winding drive (9) has a tape tension control device (16). 3.) Tape gluing device according to claim 1 or 2, characterized in that the winding drive (9) acts on the outer circumference of the tape roll (5). 4.) Tape gluing device according to claim 3, characterized in that the winding drive (9) has one or more drive rollers (10) and a controllable roller drive (11). 5.) Tape gluing device according to claim 1 or one of the following, characterized in that the winding drive (9) has a feed device (13) for positioning against the tape roll (5). 6.) Tape application device according to claim 5, characterized in that the feed device (13) has a swivel arm (14) and a feed element (15), preferably a gas spring. 7.) Tape gluing device according to claim 1 or one of the following, characterized in that the winding drive (9) has a control connection to the manipulator (2). 8.) Tape gluing device according to claim 2 or one of the following, characterized in that the tape tension control device (16) has a tape tension tester (21) which is connected to the winding drive (9) via a control (12). 9.) Tape gluing device according to claim 8, characterized in that the control (12) has a regulator (48) for adjusting the speed of the winding drive (9) to a constant tape tension. 10.) Tape application device according to claim 8 or 9, characterized in that the tape tension tester (21) has a movable tension roller (17) for the adhesive tape (7) and a position indicator (22) for determining the tape tension-dependent tension roller position. 11.) Tape application device according to claim 10, characterized in that the position indicator (22) has a swivel arm (19) for the tension roller (17) and a distance sensor (23). 12.) Tape sticking device according to claim 11, characterized in that the swivel arm (19) is mounted coaxially with the tape roll (5) and has a reflector (24) at the end for the distance sensor (23). 13.) Tape gluing device according to claim 10, 11 or 12, characterized in that the tension roller (17) has an elastic feed device (18). 14.) Tape gluing device according to claim 13, characterized in that the feed device (18) has a feed member (20), preferably a gas spring, engaging the pivot arm (19). 15.) Tape gluing device according to claim 1 or one of the following, characterized in that the winding drive (9) has a warning device (49) for the end of the winding.