Method for setting a tensile force of a wire product in a winding device, winding device and computer program product

Abstract

The invention relates to a method for setting a tensile force of a wire product in a winding device for winding a component, comprising the following steps: a. by means of a measuring device, determining an actual wire length required for winding the wire product around a component (S1); b. calculating a correction factor on the basis of the actual wire length and a target wire length (S2); and c. setting a tensile force if the correction factor lies outside a specified tolerance range for a target tensile force (S3). The invention also relates to a winding device for winding a wire product around a component and to a computer program product comprising commands which cause the winding device to carry out the method.

Description

[0001] Method for adjusting the tensile force of a wire-shaped material in a winding device, winding device and computer program product

[0002] The present invention relates to a method for adjusting the tensile force of a wire-like material in a winding device for wrapping a component. The invention further relates to a winding device for wrapping a component with a wire-like material and to a computer program product.

[0003] Today, rotors or stators for electric motors are wound with a wire-like material, such as metal wire, using a winding device and a technique known as needle winding. For the winding process, the wire is fed from a wire drum to the winding device via a wire feeder. Inside the winding device, the wire is guided under tension over several wheels and fed to a winding needle, which then wraps the rotor or stator with the wire.

[0004] Optimal winding of the rotor or stator with the wire requires optimal tension of the wire within the winding device. The challenge in needle winding lies in maintaining consistent wire tension across the entire wire drum. The wire tension is manually calibrated by the operator when changing wire drums. Incorrect calibration and fluctuations in the wire within the drum impair the reproducibility of the layer build-up during needle winding, resulting in increased scrap. The manual calibration process is highly error-prone. Furthermore, even if the incorrect wire tension is detected, the operator must manually recalibrate it.

[0005] To circumvent this disadvantage, DE 76 26 879 U discloses a device for generating a uniform pulling force of a wire guided from a supply spool to a winding device. The device has two rollers wrapped with wire and a guide roller located downstream of the two rollers and arranged on a support arm coupled to a spring. One of the two rollers is mounted on a lever arm to which a brake band is attached, guided via a friction flange coaxially connected to the other roller.

[0006] Furthermore, DE 102004 020465 B3 discloses a wire tension regulator for winding machines, consisting of a brake adjustment system for applying a specific tension to the coil windings and a control loop for determining a setpoint-actual value comparison and controlling an actuator. The brake adjustment system, acting as an actuator, comprises a voice coil actuator and a jaw system.

[0007] The present invention is based on the objective of creating a method, a winding device and a computer program product that enable improved adjustment of the tensile force of a wire-shaped material in a winding device.

[0008] To solve the problem, a method with the features of claim 1, a winding device with the features of claim 5, and a computer program product with the features of claim 8 are proposed.

[0009] Advantageous embodiments of the method and the winding device are the subject of the respective dependent claims.

[0010] According to a first aspect of the invention, a method for adjusting, in particular automatically adjusting, a tensile force of a wire-like material in a winding device for wrapping a component is proposed. In the first step of the method, the actual wire length required to wrap a component with the wire-like material is determined by means of a measuring device. In a second step, a correction factor is calculated based on the actual wire length and a target wire length. In a third step, a tensile force is set if the correction factor lies outside a predetermined tolerance range for the target wire length.

[0011] The method according to the invention is based on the understanding that the tensile force correlates with the wire length; that is, a higher tensile force corresponds to a shorter wire length and a lower tensile force corresponds to a longer wire length. A correction factor is calculated by specifying a target wire length, i.e., an optimal wire length with which the component is to be wrapped, and an actual wire length required to wrap a component with the wire. Based on this correction factor, the tensile force of the wire can then be adjusted for the next component to be wrapped with the wire, provided the correction factor lies outside a predetermined tolerance range for the target wire length. If the correction factor is above the predetermined tolerance range, i.e., the actual wire length is longer than the target wire length, then the tensile force is too low and must be increased.If the correction factor is below the specified tolerance range, meaning the actual wire length is shorter than the target wire length, then the tensile force is too high and must be reduced. This significantly increases the accuracy of the set tensile force. Calibration by the operator during wire drum changes can even become unnecessary, as the winding device automatically corrects for variations in the wire. Consequently, compared to the prior art, this method offers improved tension setting for wire within a winding device.

[0012] The component can be a stator or rotor of an electric motor, or a coil for an electrical device such as a transformer or an electromagnet. The wire-like material can be a metal wire, such as an aluminum or copper wire.

[0013] The actual wire length, as defined in the invention, is the length of wire with which a component has been wound. The target wire length, as defined in the invention, is the optimal wire length for wrapping the component. Advantageously, the actual wire length and / or the target wire length are measured when the wire is fed to the winding device, particularly in the area of ​​the wire feed of the winding device. That is, the actual wire length and / or the target wire length is measured before the wire is fed to a wheel that is braked by a braking device. Alternatively, the wire can be measured directly at the wheel of the winding device, which is braked by a braking device.

[0014] In an advantageous embodiment, the actual wire length correlates with the tensile force or with the actual tensile force or the actual wire tension.

[0015] Advantageously, the tensile force is set for the next component to be wrapped, or for a new component. This means that the wire length used to wrap a component is measured. This wire length corresponds to the actual wire length, based on which the correction factor is calculated. If the correction factor deviates from the specified tolerance range, the tensile force used to wrap the new component is then adjusted accordingly.

[0016] In an advantageous embodiment, a braking device is controlled to adjust the tractive force. This device brakes a wheel over which the wire-like material is guided. Thus, the tractive force can be adjusted by braking the wheel. By specifying a target wire length, corresponding to an optimal wire length, and the measured actual wire length, the correction factor can be calculated. This factor can then be used to determine a calibration value for the braking device, depending on the component being wound. Advantageously, the braking device has a brake that is in constant engagement with the wheel. Increasing the braking force slows the wheel down, thereby increasing the tractive force. Conversely, reducing the braking force releases the brake, thus reducing the tractive force.

[0017] In an advantageous embodiment, the actual wire length is determined by measuring the revolutions of a wheel over which the wire is guided. For example, the measuring device can be an incremental encoder that measures the wheel's revolutions. Alternatively, an encoder from a servo drive used to brake the wheel can be used to measure the wheel's revolutions. The wheel can have, for example, a rubberized outer surface to guide the wire. Advantageously, the wheel is connected to the braking device. The wheel can have holes that are detected by the measuring device, such as an incremental encoder. Based on the measurement of the revolutions, the actual wire length can be determined.

[0018] In an advantageous embodiment, the tolerance range is + / - 5% of the nominal wire length. Furthermore, the tolerance range is advantageously + / - 3% of the nominal wire length. A further advantageous tolerance range is 0% of the nominal wire length.

[0019] In an advantageous embodiment, a second measuring device is used to detect component variations, such as tolerances in the height of the component to be wound. These component variations, which can further influence the wire length, can be included in the calculation of the correction factor.

[0020] According to a further aspect of the invention, a winding device for wrapping a component with a wire-like material is proposed. The winding device comprises at least one wheel having a guide for the wire-like material, a braking device configured to adjust the tensile force of the wire-like material to brake the wheel, a measuring device configured to measure revolutions of the driven wheel, and a control device configured to control the braking device and to carry out a method according to the invention.

[0021] In an advantageous embodiment, the control unit is connected to the measuring device and / or the braking device, for example, via a data cable or WLAN. The control unit can be a data processing device comprising a processing unit and a storage device for storing a computer program containing instructions that cause the winding device to execute the method according to the invention. To execute the computer program, it can be loaded into the processing unit. The processing unit can be configured as a CPU, which is set up to carry out the method according to the invention. Furthermore, the control unit can have an output device, such as a monitor, on which, for example, the tensile force and the target tensile force are displayed.Furthermore, the control device may include an input device, such as a keyboard and / or a mouse, for adjusting the traction force and / or for entering commands from the computer program product.

[0022] In an advantageous embodiment, the measuring device is designed as an incremental encoder or as an encoder of a servo drive used to brake the wheel.

[0023] Advantageously, the wheel has holes which are detected by the measuring device. This allows the measuring device to measure the wheel's revolutions and, based on this, determine the actual wire length with which a component has been wrapped.

[0024] In an advantageous embodiment, the braking device is designed as a magnetic powder brake or as a servo motor.

[0025] According to another aspect of the invention, a computer program product is proposed which includes commands that cause the winding device according to the invention to perform the method according to the invention.

[0026] The following section explains in more detail a winding device, a method for adjusting the tensile force of a wire-shaped material in the winding device, and further features and advantages using an exemplary embodiment, which is schematically illustrated in the figures. The figures show:

[0027] Fig. 1 is a schematic representation of a winding device; and

[0028] Fig. 2 shows a schematic representation of process steps of a method for adjusting a tensile force of a wire-shaped material in the winding device shown in Fig. 1.

[0029] Fig. 1 shows a winding device 10 for wrapping a component not shown, such as a rotor or a stator, with a wire-shaped material 12, which in this case is a metal wire, such as an aluminum wire or copper wire.

[0030] The winding device 10 has a wire feed 14, a wheel 16, further wheels 18, a braking device 20 for braking the wheel 16, a measuring device 22 for measuring revolutions of the wheel 16 and a control device 24 for controlling the braking device 20.

[0031] The wire-shaped material 12 is fed from a wire drum (not shown) to the wheel 16 of the winding device 10 via the wire feeder 14.

[0032] The wheel 16 serves to guide the wire-shaped material 12. The wheel 16 has a rubberized circumferential surface for guiding the wire-shaped material 12. As can be seen in Fig. 1, the wheel 16 is provided with holes 26.

[0033] The wire-shaped material 12 is guided after the wheel 16 via the further wheels 18 to a winding needle (not shown), by means of which the wire-shaped material 12 is wound around the component.

[0034] The braking device 20 includes a brake connected to the wheel 16. The brake is in constant engagement with the wheel 16. This allows the rotational speed of the wheel 16 to be increased or decreased by applying braking force to the brake. In this case, the braking device 20 is designed as a magnetic powder brake. Alternatively, the braking device 20 can be designed as a servo motor.

[0035] The measuring device 22 detects the holes 26 during the rotation of the wheel 16. Based on this, the revolutions of the wheel 16 can be determined. In this case, the measuring device 22 is designed as an incremental encoder. Alternatively, the measuring device 22 can be designed as an encoder for a servo drive used to brake the wheel.

[0036] The control unit 24 includes a processing unit (not shown), for example, a CPU, and a storage device (not shown) for storing a computer program. The control unit 24 is connected to the measuring device 22 via an interface 28, for example, a data cable or WLAN, and to the braking device 20 via another interface 28, for example, a data cable or WLAN. Thus, the revolutions of the wheel 16 detected by the measuring device 22 are transmitted to the control unit 24. In addition, the control unit 24 can control the braking device 20 to regulate its braking force and thereby decelerate the wheel 16 or increase its rotational speed.

[0037] To optimally wrap the component (not shown) with the wire-shaped material 12, it is necessary to adjust the tensile force or wire tension of the wire-shaped material 12 in the winding device 10. The procedure shown schematically in Fig. 2 is carried out to adjust the tensile force or wire tension.

[0038] In a first step S1, the actual wire length required to wrap a component with the wire-shaped material 12 is determined using the measuring device 22. For this purpose, the number of revolutions of the wheel 16 is measured using the measuring device 22, and based on this, the control unit 24 can calculate the actual wire length required to wrap the component.

[0039] In a second step S2, a correction factor is calculated using the control unit 24 based on the actual wire length and a specified target wire length, which corresponds to an optimal wire length for wrapping the component.

[0040] In a third step S3, the tensile force of the wire-shaped material 12 is adjusted if the calculated correction factor lies outside a specified tolerance range for the target wire length. This tolerance range is + / - 5% of the target wire length, specifically + / - 3% of the target wire length, and furthermore, specifically 0% of the target wire length.

[0041] Since the wire length correlates with the tensile force, that is, a higher tensile force corresponds to a shorter wire length, and a lower tensile force corresponds to a longer wire length, in the third step S3 the tensile force is adjusted by actuating the brake device 20 as follows.

[0042] If the correction factor is within the tolerance range, then the tensile force required to rewind the component is correct. In this case, the braking force of the brake is not changed (step S3.1), and the new component is rewound in a fourth step S4 using the tensile force prevailing in the rewinding device 10. If the correction factor is above the tolerance range, then the actual wire length is longer than the target wire length. This results in a tensile force that is too low and must be increased. In this case, the control unit 24 activates the rewinding device 20 to increase its braking force, thus braking the wheel 16 (step S3.2). This increases the tensile force. The new component is then rewound in the fourth step S4 using this increased tensile force.

[0043] If the correction factor is below the tolerance range, the actual wire length is shorter than the target wire length. This results in an excessively high tensile force, which must be reduced. In this case, the control unit 24 activates the brake device 20, reducing its braking force and thus increasing the rotational speed of the wheel 16 (step S3.3). This reduces the tensile force. This reduced tensile force is then used to wrap the new component in the fourth step, S4.

[0044] During the wrapping of the new component in step S4, the revolutions of the driven wheel 16 are measured using the measuring device 22 and based on this the correction factor for the tensile force for the next component to be wrapped is calculated and depending on the deviation from the tolerance range the tensile force for wrapping the next component is readjusted according to steps S1 to S3, as described above.

[0045] Any component variations, such as tolerances in the height of the component to be wrapped, which additionally affect the wire length, can be detected via a further measuring device not shown, which can be included in the calculation of the correction factor.

[0046] The winding device 10 and the procedure make it possible to significantly increase the accuracy of the set tensile force. Calibration by an employee during a wire drum change is therefore no longer necessary, as fluctuations in the tensile force are automatically corrected by the winding device 10. Reference numeral list: winding device, wire-shaped material, wire feed, wheel, further wheel, braking device, measuring device, control device, hole, interface, first step, second step, third step, no adjustment of tensile force in step S3, reduction of tensile force in step S3, increase of tensile force in step S3, fourth step

Claims

Claims 1. Method for adjusting a tensile force of a wire-shaped material (12) in a winding device (10) for wrapping a component, comprising the following steps: a. Determining an actual wire length required to wrap a component with the wire-shaped material (12) using a measuring device (22) (S1); b. Calculating a correction factor based on the actual wire length and a target wire length (S2); and c. Adjusting a tensile force if the correction factor is outside a specified tolerance range for a target tensile force (S3).

2. Method according to claim 1, characterized in that a braking device (20) is controlled to adjust the tractive force, which brakes a wheel (16) over which the wire-shaped material (12) is guided.

3. Method according to claim 1 or 2, characterized in that, to determine the actual wire length, revolutions of a wheel (16) over which the wire-shaped material (12) is guided are measured using the measuring device (22).

4. Method according to one of the preceding claims, characterized in that the tolerance range is + / - 5% of the nominal wire length, in particular + / - 3% of the nominal wire length, and furthermore in particular 0% of the nominal wire length.

5. Winding device (10) for wrapping a component with a wire-shaped material (12), comprising at least one wheel (16) which has a guide for the wire-shaped material (12), a braking device (20) which is designed to adjust a tensile force of the wire-shaped material (12). is to brake the wheel (16), a measuring device (22) which is configured to measure revolutions of the wheel (16), and a control device (24) which is configured to control the braking device (20) and to carry out a method according to one of claims 1 to 4.

6. Winding device (10) according to claim 5, characterized in that the measuring device (22) is designed as an incremental encoder or as an encoder of a servo drive used to brake the wheel.

7. Winding device (10) according to claim 5 or 6, characterized in that the braking device (20) is designed as a magnetic powder brake or as a servo motor.

8. Computer program product comprising commands that cause the winding device (10) according to one of claims 5 to 7 to execute the method according to one of claims 1 to 4.

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