EP1158083A2 - Device for changing the upper thread - Google Patents

Abstract

The apparatus to change the upper thread at a sewing machine, and especially a robot, uses a bobbin magazine (1). The robot (2) with its sewing head (15) is mounted at the workstation, which has the thread cutter and thread splicer. The bobbin magazine (1) with the bobbin change unit (12) is fitted close to the robot. The upper thread change system, at a robot sewing machine, has a bobbin magazine where a fixed holder arm is at each bobbin (5), with at least two thread clamps which hold the thread over the bobbin axis. Each bobbin is held in place by a sprung and sliding pin. The bobbin change unit has a bobbin grip on a moving slide, and at least two thread grips. The bobbin grip moves the bobbin from the magazine to the workstation and back. The two thread grips at the bobbin change unit are mounted on a rotating arm. Two controlled thread holders, at the workstation, are on an arm with vertical movement, with cutting scissors under the first thread holder. The thread splicer at the workstation is to one side of the thread movement path, and it can swing into the thread path.

Description

The invention relates to a device in the preamble of the first claim Art.

From Japanese Patent Publication No. Hei 3-5834 is a sewing machine known that a bobbin magazine for the upper threads is assigned. The spool magazine consists of a turntable on which individual bobbins with thread holders in interchangeable pads are arranged.

To replace the upper thread with another, the upper thread is on one Cut and held above the machine head of the sewing machine. After replacing the bobbin, the new upper thread with the old one Upper thread knotted by a knotting device.

This arrangement is designed for a stationary sewing machine on which stationary the coil magazine is arranged. The stationary sewing machine can only be used by one Operator are operated.

In addition, it is already known to attach a sewing head to a robot, materials, for example seat covers in the automotive industry, fully automatically to sew.

The object of the present invention is for a robot with a sewing head propose an upper thread changing device with which the upper thread automatically can be changed.

This object is achieved by the features of the first claim.

The solution is based on the knowledge that the robot is the yarn station, i.e. the at the moment you need the upper thread together with the bobbin and the thread separating and -connection device carries while the bobbin magazine with the bobbin changer is stationary in the work area of the robot. This makes it flexible Created a solution with which a robot can automatically sew materials, during the change of the upper thread quickly and reliably fully automatically can be carried out. Because the fully automatic changing of the bobbin thread already belongs to the state of the art, it becomes a fully automatic one Sewing robot created with which the sewing work quickly and easily can be carried out.

Subclaims 2 to 9 describe preferred embodiments of the invention.

Figur 1 a

eine Draufsicht auf ein Spulenmagazin mit zugeordnetem Nähroboter;

Figur 1 b

eine vergrößerte Draufsicht auf das Spulenmagazin mit Arbeitsstation;

Figur 2

eine Seitenansicht des Spulenmagazins mit Arbeitsstation am Roboter;

Figur 3

eine Seitenansicht der Arbeitsstation in Vorbereitung des Fadenwechsels;

Figur 4 a,b

Beginn des Auswechselvorganges einer Spule an das Spulenmagazin;

Figur 5

eine Detailansicht der Schere;

Figur 6

eine Detailansicht des Spulenhalters an der Arbeitsstation;

Figur 7

eine Seitenansicht des Spulenmagazins mit ausgewechselter Spule;

Figur 8 a-c

3 Stufen des Auswechselvorganges einer neuen Spule an die Arbeitsstation;

Figur 9

eine Detailansicht der Spulenübergabe;

Figur 10

eine Detailansicht des Verdrillvorganges;

Figur 11

eine Seitenansicht des Spulenmagazins nach dem Wechselvorgang.

The invention is explained in more detail below with reference to the drawings. They represent:

Figure 1 a

a plan view of a bobbin magazine with an associated sewing robot;

Figure 1 b

an enlarged plan view of the coil magazine with work station;

Figure 2

a side view of the coil magazine with workstation on the robot;

Figure 3

a side view of the workstation in preparation for thread change;

Figure 4 a, b

Start of the exchange process of a spool on the spool magazine;

Figure 5

a detailed view of the scissors;

Figure 6

a detailed view of the coil holder at the workstation;

Figure 7

a side view of the spool magazine with the spool replaced;

Figure 8 ac

3 stages of changing a new spool to the work station;

Figure 9

a detailed view of the coil transfer;

Figure 10

a detailed view of the twisting process;

Figure 11

a side view of the coil magazine after the change process.

1 a, b, a bobbin magazine 1 with a sewing robot 2 is shown in plan view.

The coil magazine 1 consists of a mounted in a stationary frame 3, drivable turntable 4, on which a number of coils 5 standing by individual Coil holders 6 are held. Each bobbin 5 has different colored threads 7, which serve as the upper thread when sewing.

Each coil holder 6 consists of a spring-loaded, longitudinally displaceable mandrel 8, which is arranged on the underside of the rotary table 4 (Figure 2). Its free the front end protrudes into the coil body. The coils can thus be done by hand put on the mandrel and removed again.

Each coil 5 is assigned a stationary holding arm 9 (FIG. 2) which is spaced apart carries three thread clips 9.1 to 9.3 laterally cantilevered. The thread clamps are arranged so that they thread 7 above the bobbin 5 in the keep the extended axis taut. The end of the thread 7 is in or immediately above the uppermost thread clamp 9.3.

The thread clamps 9.1 to 9.3 consist of a fixed and a spring-loaded Clamping jaw, with the thread clamp 9.3 additionally the possibility consists of the movable jaw from the outside with the help of a movable pin 10 open. For this purpose, the pin 10 is held in the frame 3 via a cylinder 11.

In the center of the turntable 4, a slide, movable bobbin changer 12 is provided. He makes because of his arrangement the rotary movements of the turntable 4 are not included.

The bobbin changer 12 consists of a gripper 13, which is at the level of the turntable surface is arranged and serves the coil sleeves on its outer circumference to take.

Above the gripper 13 are cantilevered on a rotatably mounted arm 14 two thread grippers 14.1 and 14.2 arranged one above the other on the bobbin changer 12 attached. The thread grippers consist of two apart and movable jaws. The arm is off-center to its axis of rotation arranged. The distance between the two thread grippers 14.1 and 14.2 is selected so that the thread below the thread clamp 9.1 and between the two Thread clamps 9.2 and 9.3 can be gripped when changing the bobbin, as further is described below.

The bobbin changer 12 has a translatory drive with straight guides, which allows him to move from the rest position shown in Figure 1, 2 (in the center of the Turn the rotary table 4) to the right in the direction of the sewing robot 2.

On the sewing robot 2 there is a known arm on its free arm Sewing head 15.

A workstation 16 is attached to the robot housing, in which on a base plate 17 the coil 5 in use is switched off and by a pair of pliers Coil gripper 18 is held. The thread 7 to be sewn is over a Thread guide 19 drawn off the bobbin 5. The thread guide 19 consists of two movable pincer-like arms, which when closed, an eyelet form, through which the thread then runs.

From the thread guide 19, the thread 7 is in turn cantilevered an arm 20 arranged first thread holder 20.1, the vertical spaced in alignment, a second thread holder 20.2 with a sensor 21 Thread detection follows. The thread then follows - again in alignment with the two thread holders 20.1 and 20.2 - a thread stopper 20.3, which in the event of thread breakage responds and holds the thread. Between the thread guide 19 and the first Thread holder 20.1 a pair of scissors 23 is provided close to the thread holder 20.1.

The scissors 23, the two thread holders 20.1 and 20.2, the sensor 21 and the thread stopper 20.3 are attached to the vertically extendable arm 20 by one Drive unit 22, which is also part of the workstation, vertically off and can be retracted. This arrangement is shown in detail in Figure 3 (Figure 3).

Furthermore, a splicer 24, the structure of which is arranged at the work station 16 need not be explained in detail, since such devices are generally known are. With the splicer 24 (Figure 4) two thread ends can be connected to each other become. The splicer 24 is arranged laterally next to the coil in the work station and can if necessary via a cylinder in the thread course between the two Thread holders 20.1 and 20.2 can be swung in with the arm 20 retracted.

Since the work station is attached to the sewing robot 2, it can do all rotary movements of the robot.

In the following, a thread changing process is explained in more detail with reference to FIGS. 1 to 11 explained.

It is assumed that the thread used in Figure 2 in work station 16 must be changed, since a different colored material is now to be sewn.

To initiate the change process, the sewing process is interrupted and The sewing robot 2 is rotated so that the bobbin 5 located in the work station 16 is exactly opposite the bobbin changer 12, as can be seen in Figure 1 a, b. In the bobbin magazine 1, the turntable is rotated so that an empty bobbin holder 6 coil 5 to be replaced. Then the mandrel 8 of one Actuator retracted so that the free mandrel end is no longer protrudes beyond the surface of the turntable (Figure 4 a).

Now the two thread holders 20.1 and 20.2 are closed, so that the Thread is locked and at the same time stretched between these thread holders. The Scissors 23 remain open. Then the drive unit 22 moves the arm 20 upwards (Figure 4 a), so that the thread 7 is taken, in which it is a piece of the Coil 5 is unwound. The coil holder 18 is then opened (FIG. 6).

At the same time or a short time later, the bobbin changer 12 is extended, i.e. moved to the right. The bobbin gripper 13 is open, as is the thread gripper 14.1 and 14.2. This allows the thread gripper to thread 7 between the Capture thread guide 19 and scissors 23 (Figure 4b). At the same time, the open coil gripper 13 between the open tongs of the coil gripper 18 and positioned the outer periphery of the coil 5.

In a further step, the bobbin gripper 13 and the two thread grippers 14.1 and 14.2 closed. The thread is now clamped between the four thread grippers. Then it is cut off by the scissors 23 (Figure 5); subsequently opens the thread guide 19.

Thus, when the bobbin changer 12 moves back, the one to be replaced Coil 5 is pulled from the work station 16 to the free space on the turntable 4 become.

When the coil 5 has reached its position on the turntable 4 (FIG. 7), is simultaneously also the cut one held by the thread grippers 14.1 and 14.2 Thread pulled into the thread clamps 9.1 and 9.2, since the thread grippers 14.1 and 14.2 are arranged below or above the thread clamps 9.1 and 9.2.

The free end of the cut thread is from the third thread clamp 9.3 recorded, for which this previously opened by the descending pin 10 (Figure 7) has been. The pin 10 then moves back into its basic position (Figure 2), whereby the free thread end is clamped.

At the same time, the mandrel 8 is arranged below the rotary table 4 Actuating device released so that its free end moves into the coil 5 can and holds them so (Figure 7).

Finally, the bobbin changer 12 moves into its left rest position (FIG. 8 a).

In a further step, the new coil 5 can now be brought to the work station 16 become.

For this purpose, the turntable 4 is rotated until the desired coil is opposite the workstation 16 is. Then the mandrel 8 through the actuator withdrawn; the coil 5 is now released. Then the Bobbin changer 12 to the right again. Here take the thread gripper 14.1 and 14.2 the thread held in the thread clamps 9.1 to 9.3 and keep it taut (Figure 8 b).

The bobbin changer 12 is then moved further in the direction of the work station 16, while at the same time the arm 14 is rotated by 180 ° (Figure 8 c). So that will achieved that the free thread end of the new bobbin points downwards, parallel to the End of the cut end of the thread that still hangs on the sewing robot (Figure 9). The two thread ends now lie side by side in a common plane.

In the next step, the splicer 24 is pivoted in from its rest position outside the thread run into the thread run. It is arranged in such a way that it two thread pieces between the thread grippers 14.1 and 14.2 or between the Thread holders 20.1 and 20.2 detected (Figure 10). For this, the arm 20 was in front of the Swinging the splicer 24 retracted again.

After the two thread ends have been linked in the splicer 24, the Thread gripper 14.1 and 14.2 opened and the bobbin changer 12 retracted into its rest position with simultaneous rotation of the holding arm 9 in its starting position (Figure 11). The thread holders 20.1 and 20.2 are also opened, while the thread guide 19 is closed.

Then the sewing head 15 can continue to work. Now there is one more known length of the different colored thread to the point of connection with the new thread is present, the changing process was not at the end of Sewing seam carried out, but so early that the old thread with his essential length can still be used to finish the seam. So the seam is only finished when the new thread near the sewing needle located. Only then is the material to be sewn changed, so that with only a small loss can be worked on the old thread.

Claims (9)

Device for changing the upper thread on a sewing device, consisting of a bobbin magazine in which at least two bobbins each with an upper thread are provided, a yarn station assigned to the sewing device and a bobbin changer for changing the bobbin between the bobbin magazine and the work station, a separating device for severing the Upper thread before thread change and a thread connecting device,
characterized in that the sewing device (2) is a robot with a sewing head (15) to which the work station (16) is attached, the work station (16) including the separating and thread connecting device and that the bobbin magazine (1) with the Coil changer (12) is arranged stationary in the work area of the robot. Device according to claim 1,
characterized in that each bobbin (5) in the bobbin magazine (1) is assigned a stationary holding arm (9) with at least two thread clamps (9.1, 9.2) which hold the thread (7) above in the bobbin axis. Device according to claim 1 or 2,
characterized in that each coil (5) is held by a spring-loaded displaceable mandrel (8). Device according to one of the preceding claims,
characterized in that the bobbin changer (12) consists of a bobbin gripper (13) attached to a movable carriage and at least two thread grippers (14.1, 14.2). Device according to one of the preceding claims,
characterized in that the bobbin gripper (13) has two tong-like arms with which it moves the bobbin to be changed from the bobbin magazine (1) to the work station (16) or vice versa. Device according to one of the preceding claims,
characterized in that the two thread grippers (14.1, 14.2) of the bobbin changer (12) are arranged on a rotatably mounted arm (14). Device according to one of the preceding claims,
characterized in that in the work station (16) two controllable thread holders (20.1, 20.2) are provided on a vertically movable arm (20). Device according to one of the preceding claims,
characterized in that scissors (23) are provided on the arm (20) below the first thread holder. Device according to one of the preceding claims,
characterized in that the thread connecting device (splicer 24) is arranged in the work station laterally outside the thread course and can be pivoted into the thread course.

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