Method and device for introducing a joining element into at least one component

Abstract

The invention relates to a method for introducing a joining element (10) into at least one component (11) along a connection axis (14) using a joining tool (30, 130) which is designed to guide the joining element (10) in the direction of the connection axis (14). The invention additionally relates to a device (20) for introducing a joining element (10) into a component, having a receiving device (31, 131), on which the joining element (10) can be received, and a drive device (32, 132) for guiding the joining element (10) into the component (11).

Description

[0001] Method and device for introducing a joining element into at least one component

[0002] The present invention relates to a method for introducing a joining element into at least one component along a connection axis by means of a joining tool which is designed to guide the joining element in the direction of the connection axis.

[0003] Especially in joining technology, the demands on process reliability, process control, and process monitoring are increasing. To meet these increasing requirements, joining technology devices, such as those for inserting joining elements into components, are equipped with a multitude of sensors to actively control processes and monitor and, in particular, visualize process variables such as speed, torque, axial force, transverse force, bending loads, and temperatures.

[0004] In many joining processes, a force is applied along a connection axis to the components to be joined and / or the joining elements. In an optimal joining process, the force or connection axis and the component surface normal or target bore axis coincide at all times during the process. Deviations from the coincidence include, for example, tilting along a transverse axis (angular offset) or a parallel axis shift (axial offset). Fig. 1 shows such deviations in comparison to an ideal case. Possible consequences of a deviation include, in particular, increased loads on the joining device, the joining element and the parts to be joined, misalignment of the joining element, failure to reach the head support, increased process variables during connection production, failure to achieve the target values ​​of the produced connection, insufficient tightness of the connection and / or increased energy and heat input.

[0005] If a joining element deviates from its target position during insertion into at least one pre-drilled component, the connection axis aligns with the bore axis, resulting in deflection of the joining tool and transverse loading of the entire system. If a joining element deviates from its target position during insertion into at least one pre-drilled component, the connection axis aligns with the surface normal upon reaching the head contact, resulting in stress or damage to the joining tool, the joining element, and the parts to be joined.

[0006] Especially in the field of flow-hole screwing (see DVS / EFB 3445-1 data sheet), such phenomena lead to known quality defects due to the high process forces. The root of this problem lies in the unique characteristics of this type of screwing. Flow-hole screwing differs from other known joining processes in key aspects. For example, a combination of one-sided accessibility and the resulting lack of counter-holding, as well as high joining forces, leads to partly temporary, partly permanent misalignment of joining elements during the joining process.

[0007] Previously known measures to improve this joining process have not yet led to a satisfactory solution for detecting deviations from the joining axis, and in particular misalignments of the connecting elements, during and after the process, and thus ensuring the quality of the connection. Previously known measures include, for example, the deliberate mispositioning of the screw axis before the process, a reduction in process performance, and / or subsequent destructive quality assurance in the form of macro-grinding. Based on this, the object of the invention is to provide an improved method for introducing a joining element into at least one component, as well as an improved device and an improved joining tool for introducing a joining element into at least one component.

[0008] This is achieved according to the invention by the teaching of the independent claims. Preferred developments of the invention are the subject of the dependent claims.

[0009] To achieve the object, a first aspect proposes a method for introducing a joining element into at least one component along a connecting axis by means of a joining tool which is designed to guide the joining element in the direction of the connecting axis.The method comprises the following steps: a) picking up the joining element on the joining tool; b) positioning the joining tool with the joining element on the component; c) guiding the joining element into the component, wherein c1) data of at least one process variable characterizing the load on the joining element guided into the component are recorded on the joining tool and sent to a machine control system; c2) the machine control system uses the obtained data of the at least one process variable to determine a load on the joining element and, from this, a possible deviation of the load on the joining element from a target load, thereby enabling a non-destructive assessment of the connection quality during and after guiding the joining element into the component; and d) releasing the joining tool from the joining element as soon as the joining element has been introduced into the component.The proposed method for introducing a joining element into at least one component along a connection axis is, in particular, a joining method in which joining elements such as screws, rivets, bolts, and the like are introduced into at least one component. The method encompasses all types of joining elements that are introduced into a component along a connection axis, regardless of whether they are designed as one-piece or multi-piece. The method is particularly suitable for flow-hole screwing. Furthermore, the proposed method relates to the introduction of such a joining element into at least one component, for example to connect the joining element to one or more components and / or to connect two or more components to one another using the at least one joining element. Accordingly, the further description always relates to all such cases.

[0010] The at least one component can have a component design intended for joining with a joining element, in particular one prepared for this purpose, such as an opening or recess. Likewise, the component at the connecting position can not have a special design intended for the connecting process, although such a design can be formed during the connecting process. The connecting tool is designed to guide the joining element, in particular with axial force applied, in the direction of the connecting axis and in doing so to introduce the joining element into the at least one component. During the movement of the joining element in the direction of the connecting axis, a rotational movement can also be provided at least temporarily, whereby the joining element is, for example, rotated, in particular screwed, into the component. In a special embodiment, the joining tool is designed to be arranged at a robot station.

[0011] In a first step a), the joining element is received on the joining tool. In particular, the joining tool has a receiving device, arranged particularly at its axial end, on which the at least one joining element can be received, particularly in a form-fitting manner. Of course, it can also be provided that the joining element can also be received on the receiving device, particularly in a force-fitting manner, for example, by magnetic or induction force.

[0012] In a second step b), the joining tool with the joining element is positioned on the component. In particular, the joining element is positioned at its axial end facing the component at the location on the at least one component at which the joining element is to be introduced into the component, in particular along the connecting axis. Furthermore, the joining tool with the joining element is positioned relative to the component such that the joining element is aligned with the intended connecting axis. In particular, the connecting axis is arranged coincidentally, i.e., in line with a component surface normal. In particular, the joining element is positioned concentrically with a target or connecting bore or opening provided on the at least one component.

[0013] In a third step c), the joining element is guided into the at least one component and thus inserted, wherein in a sub-step c1), data of at least one process variable characterizing the load or the load state of the joining element guided into the component is recorded on or in particular directly in the joining tool, in particular during all or part of the insertion process of the joining element into the component, and sent to a machine control system. This data is recorded in particular by means of suitable sensors, which can be arranged, for example, on the joining tool or integrated with the joining tool.In particular, this involves data from process variables acting on the joining tool, such as speed, torque, axial force, transverse force, bending load, acceleration and / or temperature, whereby these process variables can be recorded both by sensors provided for this purpose and by other devices involved in the introduction of a joining element, such as drives in particular.

[0014] In a further sub-step c2), a load on the joining element and, from this, a possible deviation of the load on the joining element from a target load or a target load state is determined, in particular by a computing device of the machine control system, with the aid of the received data of the at least one process variable recorded in particular on and / or in the joining tool. This enables, in particular, a non-destructive assessment of the connection quality while the joining element is being guided into the component, as well as on the basis of the recorded data after the joining element has been guided into the component. A target load on a joining element is defined, in particular, by data on process variables that can be recorded on the joining tool or a relationship between such process variables during a planned joining process. A deviation from the target load orA target load condition exists in particular when a value or a relationship between several values ​​of one or more process variables, particularly those recorded on the joining tool, exceeds or falls below a predetermined target value or the value of the target value is not within a specified range. Knowledge of a specific deviation from the target load during the guiding of the joining element into the component, in particular a value of the deviation in conjunction with the target value or one or more relationships thereto, allows an assessment of the quality of the process of guiding or introducing the joining element into the at least one component and thus also of the quality of a connection produced, in particular between the joining element and the component or between two components by means of the joining element.

[0015] In a fourth step d), the joining tool is released from the joining element as soon as the joining element has been inserted into the component. At this point in time, the connection is established and the process of guiding or inserting the joining element into the at least one component is accordingly completed. The proposed method enables the determination of a deviation of at least one process variable characterizing the loading of a joining element from a target process already during the insertion of the joining element into a component. Based on the determined deviation, it is possible to improve the insertion process and thus the quality of the produced connections. Furthermore, a lack of deviation or a deviation within specified tolerance values ​​can serve as evidence of the quality of the produced connection.

[0016] In one embodiment of the method for inserting a joining element into at least one component, the machine control system additionally determines, in step c2), the possible deviation of the positioning of the joining tool from a target position. The deviation can be configured, for example, as an axial or angular offset, or as a combined offset with components of such types of offset. Thus, the proposed method also enables the determination of a deviation in the positioning of a joining element from a target position already during the insertion of the joining element into a component.

[0017] In one embodiment of the method for inserting a joining element, in a further step c3), the machine control derives at least one correction value for at least one process variable in the event of a specific deviation, in particular in the load on the joining element or the positioning of the joining tool. The at least one correction value for the at least one process variable characterizing the deviation can be derived in particular from at least one value characterizing the deviation, in particular in conjunction with at least one target variable of the process variable or, for example, a relationship between several target variables of one or more process variables detected, in particular, on the joining tool. The at least one derived correction value can, for example, be used as a basis for improving a joining process that is still ongoing at the time the deviation is detected and / or a subsequent joining process.

[0018] If the determined deviation and thus the at least one derived correction value relates to the positioning of the joining tool relative to the component, this can be derived from at least one process variable characterizing the deviation, in particular in conjunction with at least one target variable of a position or, for example, a relationship between several target variables of one or more process variables detected, in particular, on the joining tool. The at least one derived correction value can be used, in particular, as a basis for correcting the load or the positioning of the joining tool or the joining element of a joining process that is still ongoing at the time of the detected deviation and / or of a subsequent joining process.

[0019] In one embodiment of the method for introducing a joining element, in a further step c4) the at least one process variable is corrected using the at least one correction value for the at least one process variable derived in step c3). The correction of the at least one process variable can already take place while the current insertion of a joining element into a component is still in progress, thereby increasing the quality of the connection currently being produced. Likewise, the correction of the at least one process variable can be used to improve the process. The correction of the at least one process variable takes place after completion of the current insertion process and comes into effect during a subsequent implementation of the method for introducing a joining element into a component, thus enabling, for example, continuous process improvement.Likewise, the correction of the at least one process variable can be carried out, in particular repeatedly, after determining a deviation and deriving a correction value during the teach-in process of the method for introducing a joining element in a device provided for the application of the method. In one embodiment of the method for introducing a joining element, the joining tool can be positioned relative to the component by means of the positioning device both in a plane perpendicular to the connection axis and at at least one angle to a component surface and thus also at an angle to the original connection axis. In particular, the joining tool can be spatially freely positioned relative to the component or the component surface by means of the positioning device.In this embodiment, the positioning device can correct the positioning of the joining tool relative to the component in step c4) based on the at least one derived correction value. The correction of the positioning of the joining tool and thus also of the joining element can take place before or after and / or during the introduction of the joining element into the component. The positioning correction can take place both in a plane perpendicular to the connection axis and at least at one angle to a component surface and in particular spatially freely relative to the component or the component surface or the original connection axis. In particular, the positioning correction is carried out in such a way that the detected deviation is compensated for or, depending on the type of deviation, even at least partially overcompensated.This makes it possible to significantly improve the quality of a produced connection both during and after the joining process.

[0020] In one embodiment of the method for introducing a joining element, in a further step e), the at least one correction value derived in step c3) is used for positioning the joining tool when performing step b), i.e., positioning the joining tool with the joining element on the component. In particular, step e) is carried out during a subsequent joining process and thereby during a subsequent implementation of the method for introducing a joining element. In this way, it is possible to improve the proposed method during repeated implementation, particularly with regard to the quality of the connections produced. This method step can be used particularly advantageously during the teach-in process of a method for introducing a joining element.

[0021] In one embodiment of the method for inserting a connecting element, the data of the at least one process variable recorded on the joining tool in step c1) are suitable for determining a transverse force acting on the joining tool and / or the joining element. The transverse force acting on the joining tool during the joining process is suitable as a parameter for the component load and thus for monitoring the quality of the connection produced. In particular, its value also represents a measure of a possible deviation of the positioning of the joining tool from its target positioning. Thus, by monitoring the transverse force already during the insertion of a joining element, a possible deviation of the component load from the target load can be determined and at least one correction value for the process variables during the insertion of the joining element into the component can be derived.Furthermore, the transverse force also represents a parameter by which a deviation in the positioning of the joining tool can be determined and at least one correction value for the positioning of the joining tool can be derived. Thus, a transverse force acting on the component and thus also on the joining element or joining tool results in a tilting moment at at least one bearing point of the joining tool. Based on an analysis of the component stiffnesses of the components involved in the joining process of the device used for the joining process, in conjunction with the transverse force recorded in the process, it is possible to monitor and / or prevent pressure ellipse truncation in the rolling element bearings of the joining tool and / or other components.

[0022] In a second aspect, a device for introducing a joining element into at least one component along a connection axis is proposed to achieve the object. For introducing the joining element, the device has a joining tool which is designed to guide the joining element in the direction of the connection axis. The joining tool has a receiving device on which a joining element can be received on the joining tool, and a drive device for guiding the joining element into the component. A sensor device for detecting related data of at least one process variable characterizing the load of a joining element guided into the component is arranged on or directly in the joining tool of the device.Furthermore, the device has a machine control which is configured to determine a possible deviation of the load of the joining element from a target load using the recorded data of the at least one process variable.

[0023] The proposed device is particularly suitable for performing one or more steps of the previously proposed method for introducing a joining element into at least one component. In particular, the device enables a non-destructive assessment of the connection quality during and after the joining element is inserted into the component. Aspects of the method that influence the design of elements of the device or the elements to be joined and their relationship to one another are to be understood analogously to the preceding description and are therefore not explained separately in connection with the proposed device.

[0024] The joining tool of the device is designed to guide the joining element, in particular subjected to axial force, in the direction of the connection axis and to introduce the joining element into the at least one component. To accommodate a joining element, the joining tool has a receiving device, arranged for this purpose, in particular at its axial end facing the component, on which the at least one joining element can be received, in particular, in a form-fitting manner. Furthermore, the receiving device can also be designed such that a joining element can be received on the receiving device, in particular in addition to a form-fitting manner, also at least partially in a force-fitting manner, for example by means of magnetic or induction force.The joining tool has a drive device or is connected to a drive device for guiding a joining element received in the holder, in particular by applying force and in particular in a longitudinal movement in the direction of the connection axis. The drive device can be configured to drive the joining element at least temporarily, in particular in addition to the axial loading, also in a rotating manner, whereby the joining element is, for example, rotated, in particular screwed, into the component.

[0025] A sensor device for recording data of at least one process variable characterizing the load on an adjacent joining element is arranged on or directly in the joining tool of the proposed device. In this case, “arranged on the joining tool” is to be understood as meaning that the at least one sensor device is provided on the device in such a way that process variables acting on the joining tool can be recorded by means of it. Accordingly, the sensor device can, for example, be designed directly on the joining tool itself, in the immediate vicinity of it, or integrated with the joining tool. In this case, being arranged directly in the joining tool is to be understood as meaning, for example, a mounting of a sensor device in a bore or groove of an element of the joining tool which transmits the force flow when a joining element is introduced. The sensor device can comprise one or more sensors orSensor elements have one or more process variables that can be detected by means of the one or more sensor elements. The sensor elements are particularly designed to utilize one or more physical effects to detect the at least one process variable.

[0026] Furthermore, the device has at least one machine control which is set up to determine a possible deviation from the target load with the aid of the recorded data of the at least one process variable. As already explained, a target load defines in particular a process variable that can be recorded on the joining tool or a relationship between such process variables during a planned joining process. A deviation from the target load occurs in particular when a value or a relationship between values ​​of one or more process variables, recorded in particular on the joining tool, exceeds or falls below a predetermined target value. Knowledge of a specific deviation from the target load, in particular a value of the deviation in conjunction with the target load during the guiding of the joining element into the component, in particular a value of the deviation in conjunction with the target value orone or more relations thereto allows a particularly non-destructive assessment of the connection quality of the process of guiding or introducing the joining element into the at least one component and thus also of the quality of the connection produced, in particular between the joining element and the component or between two components by means of the joining element.

[0027] The proposed device enables the determination of a deviation in the loading of the joining element using recorded data of at least one process variable, particularly during the guiding or insertion of a joining element into a component. Based on a specific deviation in the loading of the joining element from a target load, a particularly non-destructive assessment of the connection quality is possible during and after the guiding of the joining element into the component. This also makes it possible to adapt the target process of the device in such a way that the insertion process and thus the quality of connections produced with the device are improved. Furthermore, a lack of deviation in the loading of the joining element or a deviation within specified tolerance values ​​can represent evidence of the quality of the produced connection.

[0028] In one embodiment of the device, the machine control system is configured to use the acquired data of the at least one process variable to determine a possible deviation of the actual position of the joining tool from a target position. The deviation can be, for example, an axial or angular offset or a combined offset, particularly with components of such offset types. The device is particularly designed such that a deviation of the actual position of a joining element from a target position can be determined while the joining element is being guided or inserted into a component.

[0029] One embodiment of the device comprises a positioning device for supporting and positioning the joining tool on the component. By means of the positioning device, the joining tool can be positioned relative to the component both in a plane perpendicular to the connection axis and at an angle to a component surface. In particular, the positioning device is configured to position the joining tool spatially freely relative to the component or the component surface.

[0030] In one embodiment of the device, the positioning device is configured to correct the positioning of the joining tool relative to the component. In particular, the positioning device is designed such that positioning or correction of the position of the joining tool or of a joining element arranged thereon can be carried out at least partially before, during, and / or after the joining element is inserted into a component.

[0031] In one embodiment of the device, the sensor device is configured to detect at least one process variable selected from a group comprising the process variables rotational speed, torque, axial force, transverse force, bending load, acceleration, and temperature. Of course, the group may include further process variables that can be detected by the sensor device of the device and by means of which at least one process variable can be detected, from the value of which, or in conjunction with the value of which or the value of at least one further process variable, a possible deviation of the component load from a target load and / or a possible deviation from a target positioning of a joining element can be determined.

[0032] In one embodiment of the device, the machine control system is configured to determine at least one reaction variable acting on the joining tool, such as the transverse force, the normal force, and / or the torque, from the data of the at least one recorded process variable. The reaction variable used in each case can either be recorded directly or determined based on a relationship between the values ​​of at least two process variables. For example, a transverse force acting on the joining tool can be determined using a (bending) normal stress sensor element.

[0033] In a third aspect, to achieve the object, a joining tool is proposed for introducing a joining element into at least one component along a connection axis, which is designed to guide the joining element in the direction of the connection axis, wherein the joining tool has a receiving device on which the joining element can be received on the joining tool. The proposed joining tool has at least one sensor device for detecting data of at least one process variable detectable on the joining tool, which sensor device is designed to be integrated with the joining tool. In particular, the joining tool is designed to be used when carrying out the method described above, in particular also in conjunction with the device described above.

[0034] In an integrated design of a sensor device with the joining tool, the sensor device represents a functional unit with the joining tool. In particular, elements of the joining tool also serve to implement at least one function of the sensor device integrated therewith, such as, for example, transmitting temperatures or forces or deformations to measuring elements of the at least one sensor device or also for shielding the sensor elements from the environment.

[0035] Accordingly, the at least one sensor device of the joining tool, which is integrated with the joining tool, is particularly configured to interact with at least one element of the joining tool in order to detect the respective process variable(s). For this purpose, the sensor device can be arranged in a cavity formed inside the joining tool. For example, strain gauges arranged inside the joining tool and integrally connected to a structural element of the joining tool can directly detect forces acting during the joining process or resulting strains of the joining tool. Furthermore, motion sensors can be arranged inside the joining tool or at least partially formed by the joining tool, which detect movements of the joining tool, such as its rotational speed or its axial and / or rotational forces or accelerations.In the same way, a plurality of additional sensor elements, which are suitable for detecting one or more process variables to determine a possible deviation from the target process, can be integrated with the joining tool.

[0036] In particular, the joining tool has a drive device or is connected to a drive device for guiding a joining element received in the holder, in particular by applying force and in particular in a longitudinal movement in the direction of the connection axis. The drive device can also be designed to impart a rotational movement to the joining tool, in particular to drive the joining element in a rotational motion at least temporarily during the movement of the joining element in the direction of the connection axis, so that the joining element can be screwed or rotated into the component by means of the joining tool.

[0037] To accommodate a joining element, the joining tool has a receiving device, arranged in particular at its axial end facing the component, on which the at least one joining element can be received, in particular, in a form-fitting manner. The receiving device can also be designed such that, in addition to a form-fitting reception, a joining element can also be received at least partially in a force-fitting manner, for example, by means of magnetic or induction force.

[0038] In order to capture the process variables required to determine a deviation from a target process, a suitable joining tool design is required, particularly with regard to its geometry, material properties, and geometric resistance. To achieve this, the joining tool must be adapted to the boundary conditions of the intended joining task, which, in particular, also enables the capture of multiple measured variables at one position on the component.

[0039] The proposed joining tool enables the determination of a deviation of at least one process variable from a target process during the insertion of the joining element into a component. Based on the determined deviation, it is possible, particularly according to the proposed method, to record the component load during the insertion process and thus evaluate and improve the quality of the produced connections. Furthermore, a lack of deviation or a deviation within specified tolerance values ​​of the component load can serve as evidence of the quality of the produced connection.Features and properties of the proposed joining tool, particularly in connection with inserting a joining element into a component, are essentially analogous to the previously described device for inserting a joining element, in conjunction with which the embodiment of the joining tool described here can be used for inserting a joining element into a component. Aspects of the method and properties of the device that influence the design of elements of the device or the elements to be joined and their relationship to one another are to be understood analogously to the preceding description and are therefore not explained separately for this specific embodiment of the joining tool.

[0040] One embodiment of the joining tool has an interface for supplying power and / or data to the at least one sensor device integrated with the joining tool. A preferred embodiment has a single such interface; however, in an embodiment in which a power and / or data supply to at least one sensor device is not compatible with the power and / or data supply to at least one further sensor device, at least one further interface may be required. Particularly for devices with a screwdriver stroke, in which the power supply and data transmission must be ensured across an axial range, the number of required connection points can be reduced, thereby facilitating cable routing to and from the joining tool.

[0041] In one embodiment of the joining tool, data transmission from at least one sensor device integrated with the joining tool takes place via a wireless connection. For example, data transmission takes place, in particular, over longer distances via Bluetooth, WLAN, IWLAN, or Li-Fi. This design is particularly advantageous when using so-called intelligent sensor devices.

[0042] In one embodiment of the joining tool, the power supply to at least one sensor device integrated with the joining tool is provided by energy storage devices such as batteries or accumulators. This design advantageously eliminates the need for cable guides or devices for inductive energy transmission.

[0043] In one embodiment of the joining tool, the power and / or data supply to at least one sensor device integrated with the joining tool is inductive. An induction coil can be used for the power and / or data supply, which in particular extends over a sufficient stroke length of the joining tool. This design advantageously eliminates the need for cable guides for the power and / or data supply.

[0044] In one embodiment of the joining tool, the receiving device and the at least one integrated sensor device are arranged in the direction of a connection axis in front of a bearing of the joining tool. If the sensor device is arranged in front of a bearing of the joining tool, it is arranged in particular at a short distance or in the immediate vicinity of the screwing location. The process variables should be recorded with as little distortion as possible. Therefore, torque and force sensors in particular are best arranged in the immediate vicinity of the process-relevant location and thus in front of a first bearing point of the joining tool. With increasing proximity of the sensor device to the screwing location, the measurement result that can be recorded with the sensor device improves and thus the quality of detecting a deviation of a joining process from the target process.

[0045] In one embodiment of the joining tool, the sensor device is configured to detect at least one process variable selected from a group comprising the process variables speed, torque, axial force, transverse force, bending load, vibration, acceleration, and temperature. From the data of these process variables, at least one reaction variable acting on the joining tool, such as the transverse force, the normal force, and / or the torque, can be determined.

[0046] Further advantages, features, and possible applications of the present invention will become apparent from the following description in conjunction with the figures. They show:

[0047] Fig. 1 : a schematic representation of examples of a faulty

[0048] Positioning of joining elements compared with optimal positioning;

[0049] Fig. 2: an exemplary embodiment of an inventive

[0050] Device for introducing a joining element into at least one component;

[0051] Fig. 3: an exemplary embodiment of an inventive

[0052] Joining tool for introducing a joining element into at least one component;

[0053] Fig. 4: shows a joining tool with integrated sensor element; and

[0054] Fig. 5: a schematic representation of a flow diagram of an exemplary method according to the invention for introducing a joining element into at least one component.

[0055] Fig. 1 shows various situations when positioning joining elements 10 for insertion into a component 11. In the top row, a joining element 10 is shown from above during the insertion process into a component 11. The left-hand illustration shows ideal positioning, which can subsequently be joined without deviation and, in particular, without transverse forces. The middle illustration shows an axial positioning error, which typically arises from manufacturing tolerances of a pilot hole 12 in the component 11 or inaccurate positioning of the joining tool. In order to enable the insertion of the joining element 10 into the component 11 despite the axial positioning error, both the joining elements 10 and the component 11 can be provided with chamfers 10a, 11a. This allows the joining element 10 to be inserted into the component 11 by the axial joining force F even with an offset a.If the position of the joining element 10 and thus the position of the force introduction is not corrected, an increased load or an increased load state of the joining element 10 arises when the joining element 10 is inserted into the component 11. The two illustrations on the far right show an angular misalignment error. The inclined connecting axis 14' has an angle ß to a component surface 11b and correspondingly an angle α to the intended connecting axis 14. In this case, the inclination of the joining tool 30 does not coincide with the component surface normal or, if a pilot hole 12 is present, with the hole axis. If the joining element 10 is nevertheless inserted into the component 11 in this situation, the joining axis 14 adapts to the axis of the pilot hole 12 during the insertion process.This leads to a bending stress on the joining tool 30 and to a bending load on the joining element 10, which is also reflected in a transverse load on the entire device 20.

[0056] Fig. 2 shows an exemplary embodiment of a device 20 according to the invention for introducing a joining element 12 into a component 11 along a connection axis 14 using a joining tool 30. The joining tool 30 is designed to guide the joining element 10 in the direction of the connection axis 14 and has a receiving device 31 for receiving the joining element 10 on the joining tool 30. Furthermore, the device 20 has a drive device 32 for guiding the joining element 10 into the component 11. A sensor device 33 for detecting data of at least one process variable is arranged on the joining tool 10.The sensor device 33 is configured to detect at least one process variable, such as an axial force F applied by the joining tool 30, a torque applied by the joining tool 30 and / or the speed of rotation, or forces acting on the joining tool 30 such as the transverse force, the bending load, the acceleration or the temperature of the joining tool 30 at a predetermined position.

[0057] The exemplary device 20 shown in Fig. 2 further comprises a

[0058] Positioning device 35 for supporting and positioning the joining tool 30 and thus the joining element 10 on the component 11. By means of the positioning device 35, the joining tool 10 can be positioned relative to the component 11 both in a plane perpendicular to the connection axis 11 and at an angle ß to the surface 11b of the component 11, which in particular faces the joining element 10. The exemplary positioning device 35, here a multi-axis robot, is configured to correct the positioning of the joining tool 10 relative to the component 11.

[0059] The device 20 further comprises a machine controller 40 for controlling the device 20. The machine controller 40 is further configured to determine a possible deviation from the target process using the data of the at least one process variable acquired by the at least one sensor device 33. Furthermore, the machine controller 40 can be configured to determine at least one reaction variable acting on the joining tool 30, such as the transverse force, the normal force, and / or the torque, from the data of the at least one acquired process variable.

[0060] Fig. 3 shows on the right an exemplary embodiment of a joining tool 30 according to the invention for introducing a joining element 10 into at least one component 11. The left illustration in Fig. 3 shows a joining tool 130 according to the prior art, on which several sensor devices 133 are arranged. A drive device 132 serves to drive the joining tool 130. The recording of the process variables should be as authentic as possible, which is why sensor devices 133 are attached to the joining tool 130 as close as possible to the receptacle 131 of a joining element 10. As can be seen from the left illustration in Fig. 3, this is not easily possible, especially with single-size sensors 133. In addition, no bearings 134 can be provided in the installation space used for sensor devices 133, which ensures greater distances and thus greater leverage.The size of the sensors 133 also has a direct influence on the overall length of the joining tool 130, which is particularly disadvantageous in robot-guided applications. The right-hand illustration in Fig. 3 shows an exemplary joining tool 30 according to the invention for introducing a joining element 10 into at least one component 11 along a connecting axis 14. The joining tool 30 has a receiving device 31, on which a joining element 10 can be received on the joining tool 30. In the exemplary joining tool 30 according to the invention, at least one sensor device 33 for recording data of at least one process variable that can be recorded on the joining tool 30 is integrated with the joining tool 30. The receiving device 31 and the at least one integrated sensor device 33 are arranged in the direction of the connecting axis 14 in front of a bearing 34 of the joining tool 30. The joining tool 30 is also connected to a drive device 32.

[0061] The joining tool 30 further comprises an interface 36 for supplying energy and / or data to the at least one sensor device 33 integrated with the joining tool 30, wherein the data transmission of at least one sensor device 33 integrated with the joining tool 30 can take place via a wireless connection.

[0062] The energy supply of at least one sensor device 33 integrated with the exemplary joining tool 30 according to the invention is provided by an energy storage device 37, wherein the energy and / or data supply of at least one sensor device 33 integrated with the joining tool 30 can also be provided inductively.

[0063] Fig. 4 shows a joining tool 30 with an integrated sensor device 33 in the form of a transverse force sensor 33a. A joining element 10, designed, for example, as a flow-hole and thread-forming screw, is arranged on the receiving device 31 of the joining tool and is guided into a component 11 in the form of a sheet metal. An engagement element, designed, for example, as a bit, is arranged on the receiving device 31 and is located in the engagement feature of the head of the joining element 10. While the joining tool 30 guides the joining element 10 into the component 11, the transverse force sensor 33 detects the transverse force F acting on the joining tool 30. The detected data of the transverse force F represent data of a process variable that characterizes the load on the joining element 10 and is sent to a machine control system.

[0064] In the exemplary embodiment shown in Fig. 4, a transverse force F resulting from the insertion process acts at the connection point between the receiving device 31 and the head of the joining element 10, from which a load on the joining element 10 can be derived. The resulting transverse force F leads to a measurable bending stress on the joining tool 30 and, at the same time, to a bending load on the joining element 10. In the exemplary embodiment, the detected transverse force F thus represents the process variable that characterizes the load on the joining element 10, and the data for this is sent to the machine control system.

[0065] The machine control system uses this data to determine the load on the joining element 10. In the exemplary embodiment, this is done taking into account the distance a of the transverse force sensor 33a and the distance s of the joining element 10 from the surface of the component 11 into which the joining element 11 is to be introduced. The calibration of the transverse force sensor 33a was carried out taking these distances into account. A load on the joining element 10 due to the transverse force F acting on the joining element 10 can thus be determined using at least one process variable recorded in the joining tool 30. With knowledge of the distances a and s, the bending load on the joining element during the joining process can also be calculated. In this way, a possible deviation of the load on the joining element 10 from a target load, in the exemplary embodiment in particular a target load defined by a transverse force or a bending load, can be determined.This allows the connection quality to be assessed while the joining element 10 is being guided into the component 11. In conjunction with the storage of the data of at least one process variable recorded during insertion, it is also possible to evaluate the connection quality at a later time.

[0066] Fig. 5 shows a schematic representation of a flow diagram of an exemplary method according to the invention for introducing a joining element 10 into at least one component 11 along a connecting axis 14 by means of a joining tool 30, which is designed to guide the joining element 10 in the direction of the connecting axis 14. In a first step a), the joining element 10 is received on the joining tool 30. In a second step b), the joining tool 30 with the joining element 10 is positioned on the component 11 and guided into the component 11 in step c).In a sub-step c1), data of at least one process variable characterizing the load on the joining element 10 during its guidance into the component 11 are recorded on the joining tool 30 and sent to a machine control 40. In a further sub-step c2), the machine control 40 uses the obtained data of the at least one process variable to determine a possible deviation of the load on the joining element 10 from a target load, thus enabling a non-destructive assessment of the connection quality during and after the joining element 10 is guided into the component 11. Once the joining element 10 has been introduced into the component 11, the joining tool 30 is released from the joining element 10 in step d).The data of the at least one process variable characterizing the load on the adjacent joining element 10 recorded on the joining tool 30 in step c1) are particularly suitable for determining the load on the joining element 10 by a transverse force acting on it.

[0067] Optionally, in step c2), the machine control system 40 can determine the possible deviation of the positioning of the joining tool 30 from a target positioning. Also optionally, in step c), a further sub-step c3) can be executed, in which the machine control system 40 derives at least one correction value for at least one process variable in the event of a specific deviation in the load on the joining element 10 and / or the positioning of the joining tool 30.

[0068] In a further optional sub-step c4), the at least one process variable is corrected using the at least one correction value derived in step c3) for this at least one process variable. In an embodiment of the device 20 in which the joining tool 30 can be positioned relative to the component 11 by means of a positioning device 35 both in a plane perpendicular to the connection axis 14 and at at least one angle β to a component surface 11b, the positioning of the joining tool 30 relative to the component 11 can be corrected based on the at least one derived correction value.

[0069] In a further optional step e), the at least one correction value derived in step c3) is used for the positioning of the joining tool 30 when carrying out step b), the positioning of the joining tool 30 with the joining element 10 on the component 11 during a subsequent implementation of the method for introducing a joining element 10.

Claims

Claims: A method for introducing an joining element (10) into at least one component (11) along a connecting axis (14) by means of a joining tool (30, 130) which is configured to guide the joining element (10) in the direction of the connecting axis (14), comprising the following steps: a) picking up the joining element (10) on the joining tool (30, 130); b) positioning the joining tool (30, 130) with the joining element (10) on the component (11); c) guiding the joining element (10) into the component (11), wherein c1) data of at least one process parameter characterizing the load of a joining element (10) guided into the component (11) are acquired on the joining tool (30, 130) and sent to a machine control (40);c2) the machine control (40) uses the obtained data of the at least one process parameter to determine a load on the joining element and, from this, a possible deviation of the load on the joining element from a target load, thereby enabling a non-destructive evaluation of the joint quality during and after the insertion of the joining element (10) into the component (11); and d) releasing the joining tool (30, 130) from the joining element (10) as soon as the joining element (10) has been inserted into the component (11). Method for inserting a joining element (10) according to claim 1, characterized in that in step c2) the machine control (40) additionally determines the possible deviation of the positioning of the joining tool (30, 130) from a target position. Method for inserting a joining element (10) according to one of the preceding claims, characterized by the further step: c3) the machine control (40) instructs in the case of a certain Deviation at least one correction value for at least one process variable. Method for introducing a joining element (10) according to claim 3, characterized by the further step: c4) correcting the at least one process variable using the at least one correction value for the at least one process variable derived in step c3). Method for introducing a joining element (10) according to claim 4, wherein the joining tool (30, 130) can be positioned relative to the component (11) by means of a positioning device (35) both in a plane perpendicular to the joining axis (14) and at least one angle (β) to a component surface (11b), characterized in that the positioning device (35) corrects the positioning of the joining tool (30, 130) relative to the component (11) in step c4) based on the at least one derived correction value.Method for introducing a joining element (10) according to at least one of claims 3 to 5, characterized by the further step: e) using the at least one derived in step c3). Correction value for the positioning of the joining tool (30, 130) during the execution of step b), the positioning of the joining tool (30, 130) with the joining element (10) on the component (11), in a subsequent execution of the method for inserting a joining element (10). Method for inserting a joining element (10) according to at least one of the preceding claims, characterized in that the data of at least one process variable recorded in step c1) on the joining tool (30, 130) are suitable to determine a transverse force acting on the joining tool (30, 130) and / or on the joining element (10).Device (20) for inserting a joining element (10) into at least one component (11) along a connecting axis (14) with a joining tool (30, 130) which is designed to guide the joining element (10) in the direction of the connecting axis (14), with a receiving device (31, 131) on which the joining element (10) can be received on the joining tool (30, 130) and a drive device (32, 132) for guiding the joining element (10) into the component (11), characterized by a sensor device (33, 133) arranged on the joining tool (30, 130) for acquiring data of at least one process variable characterizing the load on an adjacent joining element (10) and a machine control (40) which is configured to use the acquired data of the at least one process variable to detect a possible deviation from the target load of the joining element. (10) to determine.Device for inserting a joining element (10) into at least one component (11) according to claim 8, characterized in that the machine control (40) is configured to determine, using the acquired data of the at least one process variable, a possible deviation of the actual position of the joining tool (30, 130) from a target position. Device for inserting a joining element (10) into at least one component (11) according to claim 9, characterized by a positioning device (35) for storing and positioning the joining tool (30, 130) on the component (11), wherein the joining tool (30, 130) is positioned relative to the component (11) by means of the positioning device (35). The device can be positioned both in a plane perpendicular to the connection axis (14) and at an angle (β) to a component surface (11b). A device for inserting a joining element (10) into at least one component (11) according to claim 10, characterized in that the positioning device (35) is configured to correct the positioning of the joining tool (30, 130) relative to the component (11). A device for inserting a joining element (10) into at least one component (11) according to at least one of claims 8 to 11, characterized in that the sensor device (33, 133) is configured to detect at least one process variable selected from a group comprising the process variables rotational speed, torque, axial force, transverse force, bending load, acceleration, and temperature.Device for introducing a joining element (10) into at least one component (11) according to at least one of claims 8 to 12, characterized in that the machine control (40) is configured to determine at least one reaction variable acting on the joining tool (30) such as the transverse force, the normal force and / or the torque from the data of the at least one detected process variable.Joining tool (30) for introducing a joining element (10) into at least one component (11) along a connecting axis (14), which is designed to guide the joining element (10) in the direction of the connecting axis (14), with a receiving device (31) on which the joining element (10) can be received on the joining tool (30), in particular for carrying out the method for introducing a joining element (10) into at least one component (11) according to at least one of claims 1 to 7, characterized in that at least one sensor device (33) for acquiring data of at least one on the joining tool (30). The detectable process variable is integrated with the joining tool (30). Joining tool according to claim 14, characterized in that the receiving device (31) and the at least one integrated sensor device (33) are arranged in the direction of a connecting axis (14) in front of a bearing (34) of the joining tool (30).

Images