Welding device and process

Abstract

The invention relates to a welding device for welding components, which includes a linear unit designed to move a component placed on it back and forth along a direction, an optical measuring unit with a detection zone directed towards a portion of the linear unit, for measuring a component placed on the linear unit, and a welding unit designed to lift a first component, preferably a ball, from the linear unit and, after a movement of the linear unit, to weld it with a second component, preferably a wire, placed in the detection zone.

Description

Title of the invention: Welding device and method

[0001] The present invention relates to a welding device and a welding method.

[0002] In modern manufacturing technology, precision and reliability are of a This is of crucial importance, particularly in safety-critical applications such as aerospace. An optimized welding setup and process play a vital role in manufacturing aircraft components. To verify the accuracy of a weld, a concentricity test is essential afterward to ensure that the welded components are precisely aligned. This is the case, for example, when welding electro-hydraulic servovalve (EHSV) components, which are typically used for aircraft control surfaces.

[0003] According to the prior art, the components were individually and manually inserted into a rigid clamping device, in which the two components were positioned relative to each other during a welding operation. After the welding process, the parts were removed from the clamping device and their concentricity was checked in a rotating device with a dial indicator. If the concentricity was outside the specified tolerance, the welded component was rejected, so the process had to be repeated with a newly adjusted clamping device. The clamping device is adjusted until the required concentricity, corresponding to the tolerances, is achieved. This process results in a high rejection rate.Furthermore, this process must be repeated with each product change, so it is not possible to weld components of different dimensions with the same clamping device setting, for example.

[0004] The concentricity test performed after welding serves to verify the accuracy of the welded joint. This test ensures that the components are precisely aligned with each other and do not exhibit any deviations that could lead to imbalances or malfunctions. To do this, a comparator is used to measure the concentricity accuracy and indicate any deviations. A comparator is a precision measuring instrument used to detect small changes in length or deviations from a reference position. It generally comprises a dial with a pointer that indicates the measured values, and a measuring rod that transmits the movement of the object being measured to the dial and is in direct contact with the object being measured.This direct contact also alters the quality and relevance of the concentricity test, because the measuring rod in contact with the object to be measured exerts a certain spring force on the object, which can affect concentricity.

[0005] Consequently, the current state of the art presents several drawbacks in the manufacture of individual parts. The significant effort required to adjust the clamping device leads to high scrap rates and lengthens the production process. The concentricity measurement performed by the comparator is often inaccurate, which affects the quality of the finished products. Furthermore, there is a lack of systematic documentation of the measurement results, which makes traceability and quality control more difficult.

[0006] The objective of the present invention is to provide a welding device and a welding process that overcome, or at least mitigate, the drawbacks of the prior art mentioned above. This is achieved with a device according to the invention and a process according to the invention.

[0007] According to the invention, the welding device for welding components comprises a linear unit, designed to move a component placed on it back and forth in one direction, an optical measuring unit with a detection zone directed towards a portion of the linear unit, for measuring a component placed on the linear unit and a welding unit, designed to lift a first component, preferably a ball, from the linear unit and, after a movement of the linear unit, weld with a second component placed in the detection zone, preferably a wire.

[0008] The combination of the linear unit, the optical measuring unit, and the welding unit makes it possible to create a welding device capable of automatically welding a first component and a second component together. Furthermore, with the help of the optical measuring unit, the result of the welding operation can also be examined, and based on this, an adjustment of the interaction of the different units can be made.

[0009] Since the components to be welded can be moved towards the linear unit, where, for example, the first component is already lifted from the linear unit by the welding unit, and since there can therefore be relative movement of the two components, it is no longer necessary to manually place and position the components together in a clamping device. The positioning of the two components relative to each other is achieved by moving the second component on the linear unit once the first component has already been lifted from the linear unit by the welding unit. This makes it possible to create a fully automatic welding process, which eliminates the tedious adjustment work on the clamping device. Finally, the positioning of the two components to be welded relative to each other is achieved by moving the linear unit relative to the welding unit.

[0010] The optical measuring unit is used to pre-test the individual components to be welded to determine whether their dimensions comply with predefined tolerances. After a welding operation, the optical measuring unit can also can be used to check the welded component with regard to its dimensions and compliance with predefined tolerances.

[0011] According to an optional development of the present invention, it may be provided that the welding unit is designed to lift the first component out of the detection area of ​​the optical measuring unit.

[0012] The linear unit can thus first move the first component into a detection zone of the optical measuring unit, so that the optical measuring unit can determine and verify the dimensions of the first component. If the dimensions are then within a predefined tolerance, the first component is lifted from the linear unit by the welding unit. Next, the linear unit moves so that the second component, which is to be welded to the first component, is transferred into the detection zone of the optical measuring unit. This results in a verification of the dimensions of the second component by the optical measuring unit before the welding of the first and second components is carried out.

[0013] According to another advantageous development of the present invention, the optical measuring unit may be provided to have an accuracy of 1 pm or more. The optical measuring unit is also called a micrometer and has a very high resolution to be able to detect any deviations in the dimensioning of the first component, the second component, or the welded component (composed of the first component and the second component welded to it).

[0014] According to an advantageous modification of the present invention, the linear unit can be designed to move the second component into the detection zone of the optical measuring unit after a first component has been lifted by the welding unit. The detection zone of the optical measuring unit remains unchanged relative to that of the linear unit, even if the optical measuring unit were to pivot in order to observe a component placed in the detection zone at an additional angle.

[0015] According to an advantageous development of the present invention, it may further be provided according to the invention that the optical measuring unit is arranged in a rotational manner relative to the linear unit to measure a component placed in the detection zone under different angles, preferably the angle of rotation of the optical measuring unit having an angle of at least 90°, preferably at least 180°.

[0016] In addition, it may be provided that the angle of rotation of the optical measuring unit does not exceed an angle of 180°.

[0017] The optical measuring unit, which can be rotated relative to the linear unit, can thus observe a welded component formed by welding the first component to the second component, from different angles and perform a measurement of the welded component in each of the observation positions angularly different. It can thus be provided that, during a pivoting of the optical measuring unit from a starting position with a minimum pivot angle to a final position with a maximum pivot angle, a continuous measurement or a multitude of measurements of the welded component at different angles are performed during the pivoting movement, so that the concentricity of the welded component can be verified. Advantageously, in the concentricity test proposed according to the invention, the welded component to be tested is not brought into contact, so that the inaccuracy typically caused by a comparator in the prior art does not occur. Finally, it is common with a comparator for a measuring head to come into contact with the component to be tested and for a relative rotation between the measuring head and the component to be performed, so that in case of imbalance, the measuring head is deflected from its original position.To allow such a deviation, however, the measuring head must be pressed against the component being measured with a certain force, which makes the concentricity measurement itself imprecise. Furthermore, the deviation on the comparator is transmitted to a display via a force sensor.

[0018] Advantageously, it can be provided according to the present invention that an axis of rotation for rotating the optical measuring unit runs in the vertical direction and is preferably orthogonal to the direction of movement of the linear unit and / or parallel to the direction of movement of the welding unit, in particular identical to the direction of movement of the welding unit.

[0019] The welding unit is mobile in the vertical direction to pick up a first component placed on the linear unit and move it upwards. After the second component is placed under the welding unit, the welding unit moves down towards the linear unit and welds the first component held by the welding unit to the second component placed on the linear unit.

[0020] According to another optional modification of the present invention, it may be provided that a workpiece holder is provided for placing at least one first component and at least one second component on the linear unit, this workpiece holder being removably coupled to the linear unit.

[0021] A workpiece holder facilitates the arrangement of numerous primary and secondary components to form several welded components. The workpiece holder is first loaded with the components required for the welding operation, and then it can be coupled to the linear unit. The workpiece holder can therefore be removably connected to the linear unit.

[0022] The invention further relates to a method for welding components, in particular with a welding device according to one of the preceding claims, comprising the following steps: Placement of a first component, preferably a ball, and a second component, preferably a wire, on a linear unit; Measurement of the first component by an optical measuring unit and verification of the accuracy and / or dimensional conformity of the first component with respect to predefined nominal values; Gripping of the first component by a welding unit and lifting of it from the linear unit; Placement of the second component, by moving the linear unit, into the detection zone of the optical measuring unit; Measurement of the second component by the optical measuring unit and verification of the accuracy and / or dimensional conformity of the second component with respect to predefined nominal values; Welding of the first component gripped by the welding unit to the second component placed on the linear unit using the welding unit.Performing a concentricity test on the welded assembly by rotating the optical measuring unit and measuring the welded assembly from different angles.

[0023] The process according to the invention enables fully automatic and reliable welding results in large quantities. Unlike conventional prior art, the tedious adjustments to the clamping device, which must be made individually for the components to be welded, are eliminated. Furthermore, the concentricity test is performed using the optical measuring unit, thus preventing potential falsifications due to a comparator probe, as is the case in prior art. In addition, the automated welding process also allows for complete documentation of the dimensions of the first and second components used, as well as the welded component. Overall, this leads to a welding process with significantly reduced scrap compared to prior art methods.It no longer happens (or much more rarely) that, due to incorrect adjustment of the clamping device in which the first component was placed relative to the second, a welded component is produced with suboptimal concentricity that cannot meet predefined tolerances. With regard to achievable speed, the method according to the invention is also preferable to the prior art.

[0024] Advantageously, it may be provided, according to the present invention, that, on the basis of the measurement of the first and / or the second component, the respective component is sorted or that the following steps are carried out with the respective component.

[0025] The optical measuring unit can use the results obtained during the measurement of the first or second component to interrupt the welding operation and use to it places a first or second component whose dimensions are within predefined tolerances.

[0026] According to an optional development of the present invention, it may be provided that, based on the measurement of the first component and before the first component is picked up by the welding unit, the linear unit is actuated to position the first component precisely for pickup by the welding unit.

[0027] The linear unit is, however, designed so that it can position the second component precisely relative to the welding unit. The welding unit itself does not need to be designed to be mobile in the direction in which the linear unit can move the second component placed on it, so a welding unit of simple design can be used. The welding unit only needs to be able to take the first component from the linear unit placed beneath it and lift it from the linear unit, so a movement capability of the welding unit in a direction perpendicular to the direction of movement of the linear unit (typically the vertical direction) is sufficient. This simplifies the construction of the welding device.Furthermore, it can be stipulated that the lifting of the first component of the linear unit occurs within the area of ​​the linear unit that corresponds to the detection area of ​​the optical measuring unit. In other words, the first component is lifted from the detection area of ​​the optical measuring unit, which covers an area of ​​the linear unit.

[0028] According to another optional modification of the present invention, it can be provided that, based on the measurement of the second component and before welding by the welding unit, the linear unit is actuated to precisely position the second component for welding to the first component held by the welding unit. After the precise positioning of the second component, the welding unit, which has held the first component, can descend and bring the first component so close to the second component that the two components can be welded together.

[0029] Furthermore, according to another development of the present invention, it may be provided that the movements made by the linear unit for the placement of the first and / or second component are recorded, in order to optimize, according to the results of the concentricity test and using an optimization algorithm which is preferably based on artificial intelligence, the movements made by the linear unit for the placement of the first component.

[0030] Thus, the position or positions of the second component relative to the welding unit are examined to determine whether the resulting welded component exhibits satisfactory concentricity or whether it falls outside the predefined tolerances. Based on the examination of a multitude of positions of the second component relative to the welding unit, an improvement in positioning can then be carried out using an optimization algorithm. It may be expected that the optimization algorithm will use machine learning and / or artificial intelligence methods to optimize the harmonization of the different units of the device with each other.

[0031] According to another optional modification of the present invention, it may be provided that, after the concentricity test, the measurement results obtained by the optical measuring unit are recorded in a file for documentation purposes. The documentation may, for example, contain the dimensions of the first, second, and / or welded component obtained by the optical measuring unit. Furthermore, other information such as the total duration of the welding operation, the date of the welding operation, the type of components used, or similar information may also be documented.

[0032] According to an advantageous development of the present invention, it can be provided that a multitude of first components and a multitude of second components are arranged on the linear unit and that after welding a first component with a second component, one proceeds with welding another first component with another second component.

[0033] The linear unit can therefore be loaded with a multitude of first components and a multitude of second components, so that after welding a first component with a second, welding another first component with another second can be continued.

[0034] According to another modification of the present invention, it may be provided that the components to be welded are part of an electro-hydraulic servovalve, in particular a ball which is to be welded with a spring, in particular a spring wire.

[0035] Other features, details and advantages of the invention are presented in the description of the figures, which show: [Fig. 1]: a schematic representation of an assembly installation according to the invention, [Fig. 2a]; [Fig. 2b]: a schematic representation of an implementation of the process according to the invention and [Fig.3]: a schematic representation of a welding device according to the invention, in top view.

[0036] [Fig.1] shows a schematic representation of an assembly installation, which may also include or represent the welding device 10 according to the present invention.

[0037] The linear unit 1 is recognized, on which several components are placed. A first of the several components must be welded by a welded connection with a second of the several components to form a welded component.

[0038] The linear unit is capable of moving several components back and forth in one direction, the path of movement of the linear unit crossing a detection zone of an optical measuring unit 2. The optical measuring unit 2 can then accurately measure the component placed in its detection zone with regard to its dimensions and its positioning relative to the welding unit.

[0039] Furthermore, the welding device 10 according to the invention includes a welding unit 3, designed to take and lift a first component of the linear unit 1 in order to carry out, after a displacement of the linear unit 1 where a second component has been placed directly under the welding unit 3, a welding of the two components together.

[0040] According to an advantageous embodiment of the welding device 10, the welding operation also takes place within the detection zone of the optical measuring unit 2, for example to perform, after welding the assembled components, a measurement of the welded component in order to determine whether the welded component meets the predefined dimensional specifications or exceeds the tolerances.

[0041] A higher control unit, not shown, is connected to both the linear unit 1, the optical measuring unit 2, and the welding unit 3, and records the respective parameters of the various settings and actions of the welding device 10 during a welding operation. This information can then be used to execute an optimization algorithm aimed at improving the welding process. The optimization algorithm can operate using artificial intelligence and autonomously optimize the settings and actions of the welding device 10.

[0042] Figures [Fig. 2a]-b represent a flow diagram of the welding process according to the invention, the diagram being divided into two separate pages (Figures 2a and 2b) due to its size.

[0043] First, a specific two-component welding program is selected, and a workpiece holder 4 is loaded according to the installation specifications. The workpiece holder can interact with the linear unit later in the process, enabling the linear unit to move the components arranged in the workpiece holder 4. Once the workpiece holder 4 is loaded and inserted into the installation, the machine operating according to the process starts the welding process.

[0044] First, the first component is moved to a predefined position where the optical measuring unit has its detection zone.

[0045] Next, using the optical measuring unit, the first component, for example a ball, is checked for accuracy and dimensional conformity to determine whether the component falls within predefined tolerance limits. If it does not, the component is sorted, allowing for replacement and manual verification of the sorted component. Subsequently, if the dimensional conformity of the first component is correct, precise positioning of the first component for pickup by the welding unit can occur. For example, the first component is positioned directly under the welding unit, so that lowering the welding unit allows it to be picked up.

[0046] When the first component is removed or lifted by the welding unit of the workpiece holder or the linear unit, the linear unit moves the second component, for example a wire, into a detection zone of the optical measuring unit to also check the dimensional conformity and accuracy of the second component.

[0047] Here too, if there is a deviation from the permissible tolerance values, the second component is sorted, while the assembly process continues if the second component is acceptable. The second component is then precisely positioned by the linear unit relative to the welding unit, so that lowering the welding unit, which holds the first component, positions the two components relative to each other in such a way that welding using the welding unit is possible.

[0048] Once the positioning of the second component is complete, the welding unit lowers and the two components are welded together, creating the welded component.

[0049] The components welded together are measured by the optical measuring unit, so that a difference is determined between the dimensions of the assembled component and the nominal dimensions of the welded component. In order to also determine the concentricity of the welded component, it is necessary to measure the welded component not only at one angle using the optical measuring unit, but at different angles. For this reason, the optical measuring unit is rotatable relative to the linear unit, so that the welded component, which is placed on the linear unit, can be measured at different angles by the optical measuring unit. The measurement by the optical measuring unit can be performed continuously during a pivoting movement or intermittently at different positions during the pivoting movement.

[0050] If the concentricity of the component is detected as being within the predefined tolerances, the measurement results are also documented for the welded component by recording the corresponding information in a file.

[0051] The measurement results concerning the concentricity of the welded component can also be used to optimize the positioning of the second component relative to the welding unit. This can be done by adjusting the parameters during the operation of the linear unit using machine learning and / or artificial intelligence algorithms. Based on the measured position of the second component and a concentricity test result, an optimization of the The positioning of the second component is performed by a modified command of the linear unit, in order to obtain an even more precise alignment of the second component with respect to the first component before welding.

[0052] Furthermore, after documenting the measurement results, the process checks whether other components are present in the workpiece holder and have not yet been welded together. If so, the linear unit is moved so that the first component is positioned under the welding unit, allowing it to be picked up by the welding unit, and the linear unit can then position the second component beneath it. The welding process to join the first and second components is then repeated.

[0053] If, on the other hand, it is found that there are no other components arranged in the workpiece holder 4, the process is complete.

[0054] Figure 3 shows a top view of a welding device 10 according to the invention, which has the same components as the welding device 10 of Figure 1. However, the pivoting capability of the optical measuring unit 2 is shown, which can pivot from 0 to 90° in the figure. It is further shown that the workpiece holder 4 can be moved back and forth along a direction of movement of the linear unit 1, so that different components arranged in the workpiece holder can be positioned under the welding unit 3. The rotational capability of the optical measuring unit 2 is necessary for the concentricity test of the welded component, as it allows the welded component to be measured from different viewing angles, thus enabling a concentricity test to be performed.The advantage of the pivoting optical measuring unit 2 is that, unlike conventional prior art, no physical contact with the welded component to be measured is required, which could distort the concentricity test. A pivoting capacity of the optical measuring unit from a first initial position to a second initial position, separated by 45°, is sufficient for adequate concentricity test accuracy. In the embodiment shown in [Fig. 3], the pivoting capacity of the optical measuring unit 2 is shown in a range of 0 to 90°, but the invention also includes alternative angular ranges. In the embodiment shown in [Fig. 3], the pivot axis for the pivoting of the optical measuring unit 2 is perpendicular to the axis of movement of the linear unit, in particular, oriented vertically. The axis of movement of the linear unit 1 is advantageously oriented horizontally.

[0055] Thanks to the invention, the components to be welded are aligned with each other automatically and with high precision (verification of dimensional conformity and accuracy). This is done using the unit of Optical measurement. Concentricity and weld result control is also carried out automatically and online.

[0056] Furthermore, thanks to the optimization algorithm, which can be based on machine learning, it is possible to continuously improve the results of the welding process as well as the working results of the welding device.

[0057] List of reference points 1 Linear Unit 2 Optical unit of measurement 3 Welding Unit 4 Coin Holders 10 Welding Device

Claims

Demands

1. Welding device (10) for welding components, comprising: a linear unit (1), designed to move a component placed on it back and forth along a direction, an optical measuring unit (2) with a detection zone directed towards a portion of the linear unit (1), for measuring a component placed on the linear unit (1), and a welding unit (3), designed to lift a first component, preferably a ball, from the linear unit (1) and, after a movement of the linear unit (1), weld a second component, preferably a wire, placed in the detection zone.

2. Welding device (10) according to the preceding claim, wherein the optical measuring unit (2) has an accuracy of 1 pm or more.

3. Welding device (10) according to any one of the preceding claims, wherein the optical measuring unit is arranged in a rotational manner relative to the linear unit, in order to measure a component placed in the detection zone under different angles, preferably the angle of rotation of the optical measuring unit (2) having an angle of at least 90°.

4. Welding device (10) according to the preceding claim 3, wherein a rotation axis for the rotation of the optical measuring unit extends in the vertical direction and is preferably orthogonal to the direction of movement of the linear unit and / or parallel to the direction of movement of the welding unit, in particular identical to the direction of movement of the welding unit.

5. Welding device (10) according to any one of the preceding claims, wherein a workpiece holder (4) is provided for the placement of at least one first component and at least one second component on the linear unit (1), this workpiece holder being removably coupled to the linear unit (1).

6. A method for welding components, in particular with a welding device (10) according to any one of the preceding claims, comprising the following steps: placing a first component, preferably a ball, and a second component, preferably a wire, on a linear unit (1); measurement of the first component using an optical measuring unit (2) and verification of the accuracy and / or dimensional conformity of the first component with respect to predefined nominal values; gripping of the first component using a welding unit (3) and lifting of the linear unit (1); placement of the second component, by means of a movement of the linear unit (1), in the detection zone of the optical measuring unit (2); measurement of the second component using the optical measuring unit (2) and verification of the accuracy and / or dimensional conformity of the second component with respect to predefined nominal values; welding of the first component taken by the welding unit (3) with the second component placed on the linear unit (1) using the welding unit (3); and carrying out a concentricity test of the welded assembly by rotating the optical measuring unit and measuring the welded assembly from different angles.

7. A method according to the preceding claim 6, wherein, based on the measurement of the first and / or second component, the respective component is sorted or the following steps are carried out with the respective component.

8. A method according to any one of the preceding claims 7 or 8, wherein, based on the measurement of the first component and before the first component is picked up by the welding unit (3), the linear unit (1) is actuated to position the first component precisely for pickup by the welding unit (3).

9. A method according to any one of the preceding claims 6 to 8, wherein, based on the measurement of the second component and before welding by the welding unit (3), the linear unit (1) is actuated to position the second component precisely for welding with the first component taken by the welding unit (3).

10. A method according to any one of the preceding claims 6 to 9, wherein the welding unit (3) lifts the first component out of the detection zone of the optical measuring unit (2).

11. A method according to any one of the preceding claims 6 to 10, wherein the movements performed by the linear unit (1) for the placement of the first component and / or second component are recorded in order to optimize, based on the results of the concentricity test and using an optimization algorithm which is preferably based on artificial intelligence, the movements made by the linear unit (1) for the placement of the first component.

12. A method according to any one of the preceding claims 6 to 11, wherein, after the concentricity test, the measurement results obtained by the optical measuring unit (2) are recorded in a file to perform documentation.

13. A method according to any one of the preceding claims 6 to 12, wherein a multitude of first components and a multitude of second components are arranged on the linear unit (1) and, after welding a first component with a second component, one continues with the welding of another first component with another second component.

14. A method according to any one of the preceding claims 6 to 13, wherein the components to be welded are part of an electro-hydraulic servovalve (EHSV), in particular a ball which is to be welded with a spring, in particular a straight spring wire.

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