Setting system

Abstract

Setting system with a setting head (5) with a stroke-adjustable setting punch (7), which drives a setting element (1) in a setting direction (S) and with a setting force (F) into at least one component (3) in a setting process, and with a control unit (9) which, in the setting process, on the basis of target setting parameters (F SOLL , s SOLL , v SOLL ) a set signal (S F ) is generated, with which a pressure generator (11, 13) can be controlled, which drives the setting punch (7) over a setting path (s) and at a setting speed (v), wherein the setting system has a sensor device (21) which detects an evasive movement of the setting head (5) and / or an evasive movement (A) of the component (3) during the setting process, wherein the control unit (9) has at least one correction module (33, 35) which, on the basis of the detected evasive movement, generates the setting signal (S F) with which the pressure generator (11, 13) can be controlled, wherein the sensor device (21) is a path / speed detector, by means of which a relative speed (v RF ) with which the setting head (5) and the component (3) move apart, and wherein a relative path (s RF ) can be detected, via which the setting head (5) and the component (3) move apart in the setting process, characterized in that the sensor device (21) has at least one sensor element (23) which is mounted on the setting head (5) so as to be adjustable in stroke in the setting direction (S) and cooperates with a sensor module (29) fastened to the setting head (5), which is in signal connection with the control unit (9), wherein the sensor element (29) can move out of the sensor head (5) by a stroke detected by the sensor module (29).

Description

[0001] The invention relates to a setting system with a setting head with a stroke-adjustable setting punch according to the preamble of claim 1.

[0002] In series production in vehicle construction, for example, a setting tool located at the distal end of a robot arm is used to set a coarse-threaded bolt. The setting tool can be part of a closed setting system in which the setting head and a counterholder with die are integrated into a rigid C-frame. During the setting process, at least one component is clamped between the setting head and the counterholder using a hold-down device. A setting punch arranged in the setting head then drives the setting element (for example, a semi-tubular self-piercing rivet) into the component. The die located on the counterholder supports an expanding movement of the setting element in the component material. In such a setting tool, the C-frame forms a closed force circuit in which an evasive movement or springback movement of the setting head counter to the setting direction is reliably prevented during the setting process.However, the C-bracket requires tool access to the joint on both sides.

[0003] In contrast, a setting system is an open system in which the setting head is not integrated into a C-frame with a counterholder. Rather, the setting head and a counterholder, which is located on the component side opposite the setting side, are force-free. In this case, the setting tool consists only of the setting head, so there is no closed force circuit between the setting head and a counterholder. During the setting process, an evasive movement or springback of the setting head can occur in the opposite direction to the setting direction, which can impair the setting result.

[0004] To prevent such impairment of the setting result, a state-of-the-art setting head operates with an excessively high setting force. This ensures a perfect setting result despite the setting head's springback, regardless of the setting head's orientation: in a normal position with a setting direction from top to bottom, in an upside-down position with a setting direction from bottom to top, and in a position with the robot arm extended.

[0005] With such an open setting system, an excessive amount of energy is required for a flawless setting process. Furthermore, due to its excessive setting force, the setting system is only suitable for massive components, but not for more delicate components, which could be damaged by excessive setting force.

[0006] A setting system of this type is known from DE 601 09 886 T2. Further setting systems are known from EP 3 943 264 A1 and DE 10 2017 204 142 A1. A method and a device for monitoring a fastener joining process are known from DE 10 2006 002 237 A1 and DE 10 2014 007 554 A1. A joining device for connecting components is known from DE 10 2017 213 323 A1.

[0007] The object of the invention is to provide a setting system which, compared to the prior art, operates with reduced energy consumption and / or can be used for more delicate components.

[0008] The object is solved by the features of claim 1. Preferred developments of the invention are disclosed in the subclaims.

[0009] The invention is based on a setting system with a setting head with a stroke-adjustable setting punch. During a setting process, the setting punch drives a setting element into at least one component in a setting direction and with a setting force. The setting system also has a control unit. During the setting process, this control unit generates a setting signal based on target setting parameters, which can be used to control a pressure generator that drives the setting punch over a setting path and at a setting speed. According to the invention, the setting system has a sensor device. This sensor detects an evasive movement of the setting head and / or an evasive movement of the component during the setting process. The control unit has at least one correction module that, based on the detected evasive movement, adapts the setting signal with which the pressure generator can be controlled. For example, the sensor device detects a springback of the setting head that is opposite to the setting direction.The control unit has at least one correction module that adjusts the setting signal with which the pressure generator can be controlled based on the detected setting head springback. Alternatively and / or additionally, the sensor device can detect an evasive movement of the component. In this case, the correction module can adjust the setting signal with which the pressure generator can be controlled based on the detected component evasive movement.

[0010] According to the invention, the setting punch is monitored and controlled using a combined force-displacement measuring system. This allows the actual setting distance traveled by the setting punch to be determined, regardless of springback of the setting head or robot arm, which may be caused, for example, by the application of the setting force to the setting element. The invention allows a dynamic distance between the setting head and the component surface to be continuously measured during the setting process. This measured value is calculated online, i.e., during the setting process, with the setting punch's setting distance. This results in the actual setting distance traveled by the setting element and its setting speed. The recorded data can be used to control / regulate the setting distance and setting speed online.Furthermore, in the setting system according to the invention, the setting force acting on the setting element during the setting process can be determined and controlled online, i.e., continuously, over the entire setting path. For example, a self-contained hydraulic system integrated into the setting head can be used as the setting ram drive. The setting ram advantageously has a lower mass to enable precise control of the setting process and rapid acceleration of the setting ram, and to avoid inertia-related re-pressure of the setting ram after the setting process is completed.

[0011] Aspects of the invention are described in detail below: The sensor device has a distance / speed detection function. The sensor device detects the relative speed at which the setting head and the component move apart during the setting process. Furthermore, the relative distance over which the setting head and the component move apart during the setting process is detected.

[0012] In a technical implementation, a target setting parameter can be the target setting speed or a value correlated with it. In the correction module, a corrected target setting speed (or a value correlated with it) can be determined based on the target setting speed and the relative speed (e.g., the setting head springback speed), which is used to generate the setting signal that controls the pressure generator.

[0013] Alternatively and / or additionally, a target setting parameter can be the target setting travel or a value correlated with it. This will be determined in the correction module based on the target setting travel and the measured relative travel (e.g., the setting head springback travel), and a corrected target setting travel will be determined on the basis of this value. The setting signal controlling the pressure generator is generated on this basis.

[0014] The invention is particularly applicable to an open setting system in which the setting head is not integrated in a C-frame with a counterholder, but rather the setting head and a counterholder are force-free to each other and are arranged on the component side opposite the setting side.

[0015] It is particularly important that the setting system is designed to be completely self-regulating. For this purpose, the setting system can also incorporate a setting force sensor, which can be used to record the actual setting force acting on the setting system during the setting process. The control unit can incorporate a comparator module that compares the recorded actual setting force with a limit value. If the actual setting force is significantly greater than the limit value, the control unit can generate a shutdown signal, which terminates the setting process and returns the setting lever to its initial position. In the initial position, a new setting element is fed to the setting head.

[0016] According to the invention, the displacement / speed of the setting head is detected mechanically. The sensor device has at least one sensor element mounted on the setting head with an adjustable stroke in the setting direction and interacting with a sensor module attached to the setting head. The sensor module has a signal connection to the control unit. At the start of the setting process, the setting element is positioned in, in particular, deformation-free contact with a component surface. At the start of the setting process, the adjustable-stroke sensor element can also be positioned in contact with the component surface. In order to detect a relative movement (i.e., springback of the setting head and / or an evasive movement of the component) during the setting process, the sensor element remains in contact with the component surface during the setting process. For this purpose, the sensor element can be supported on the component surface under spring preload.In this case, in the event of a relative movement (i.e., springback of the setting head and / or component deflection), the sensor element can move out of the setting head by a stroke detected by the sensor module. The stroke detected by the sensor module corresponds to the relative distance over which the setting head and the component move apart during the setting process.

[0017] In one embodiment, several sensor elements, for example, three sensor elements, can be arranged circumferentially distributed around the setting punch. In this case, an inclination of the setting head relative to the component surface can also be detected. Alternatively, the sensor element can be a travel / position sleeve, which is preferably arranged concentrically to the setting axis and / or surrounds the setting punch radially on the outside.

[0018] According to the invention, the parameters relating to the relative movement, in particular the springback speed and / or springback travel, can be continuously recorded during the setting process. The setting signal controlling the pressure generator can be continuously adjusted based on the springback parameters during the setting process.

[0019] According to the invention, rapid, automatic adjustment is possible even during the setting process. This primarily ensures that the setting elements can be driven into the component reproducibly and consistently at the same setting speed, regardless of the setting head orientation—that is, in a normal position with a setting direction from top to bottom, an upside-down position with a setting direction from bottom to top, and in a position with the robot arm extended.

[0020] An embodiment of the invention is described below with reference to the accompanying figures. They show: Fig. 1 a setting head with associated control unit; Fig. 2 to 5 each show views illustrating a setting process.

[0021] In the Fig. 1 shows a setting device which is arranged at a distal end of a robot arm 2 and is adjusted by means of a robot control (not shown) to a joint in which a setting element 1 (for example a coarse thread bolt) is to be driven into a component 3 during a setting process.

[0022] The setting tool consists of Fig. 1 only consists of a setting head 5 with a stroke-adjustable setting punch 7. This drives the setting element 1 into the component 3 in a setting direction S and with a setting force F. A control unit 9 is assigned to the setting head 5. The control unit 9 generates, based on target setting parameters F SOLL , v SOLL , s SOLL a set signal S F , with which a pressure generator 11 integrated in the setting head 5 can be controlled, which in the Fig. 1 is assigned a hydraulic unit with a hydraulic cylinder 13. When the hydraulic unit is activated, the hydraulic cylinder 13 is subjected to hydraulic pressure, whereby its cylinder piston 15 drives the sleeve-shaped setting punch 7 in the setting direction S.

[0023] A load cell 17 is integrated in the cylinder piston 15, which measures an actual setting force F istThe load cell 17 is connected to a comparator module 18 in the control unit 9. At the end of the setting process, the setting punch 7 presses a collar 19 of the setting element 1 into contact with the component surface. This increases the actual setting force F recorded in the load cell 17. ist If the actual setting force F measured by the load cell 17 exceeds ist a limit value F stored in the comparator module 18 G , a shutdown signal S aus generated, whereby the setting process is terminated and the setting punch 7 is returned to its reset position ( Fig. 2) is reset.

[0024] The core of the invention relates to a sensor device 21 for detecting the displacement / speed of the relative movement between the setting head 5 and the component 3 during the setting process. The sensor device 21 has a displacement / position sleeve 23 which is adjustable in the setting direction S and is arranged concentrically to the setting axis and moves around the setting punch 7. Fig. 1, the travel / position sleeve 23 is guided in a setting head guide 25 with an adjustable stroke. Furthermore, the travel / position sleeve 23 can be supported in the setting head 5 against a preload spring 27. The travel / position sleeve 23 interacts with a sensor module 29 fixedly arranged on the setting head 5, which is in signal communication with the control unit 9.

[0025] The following is based on the Fig. 2 to 5 a setting process is described: In the Fig. 2, the setting head 5 is still not engaged with the component surface. Using the robot control, the setting head 5 is adjusted to a predefined joint position (e.g., in a teach-in process), as shown in the Fig. 3 is shown. In the Fig. 3, the travel / position sleeve 23 is supported on the component surface by a spring preload. Furthermore, the setting punch 7 presses the setting element 1 with its element tip 31 into contact with the component surface without deformation. In this state, the setting process starts. During the setting process, according to the Fig. 4 by way of example to a springback R of the setting head 5 which is opposite to the setting direction S, in which the setting head 5 moves with a springback path s which is opposite to the setting path s RF and with a rebound speed v RF moved upwards. With the help of the sensor device 21, the springback travel s is measured during the setting process. RFof the setting head 5 and the springback speed v RF of the setting head 5.

[0026] The springback R of the setting head 5 leads to a relative movement (i.e. relative speed and relative path) between the setting head 5 and the component 3, which can be detected by the sensor device 21. The relative movement between the setting head 5 and the component 3 can alternatively and / or additionally also be determined by an evasive movement A ( Fig. 4) of component 3 downwards.

[0027] As from the Fig. 1, based on the recorded setting head springback speed v RF (or generally: relative speed) and the target setting speed v SOLL a corrected target setting speed v Kdetermined; this is done in a correction module 35 of the control unit 9. In the correction module 35 of the control unit 9, the amount of the detected setting head springback speed v RF to the target setting speed v SOLL added, resulting in the corrected target setting speed v SOLL results.

[0028] For example, the target setting speed v K at 20 m / s, while the amount of the recorded setting head springback speed v RF is 5 m / s. From this, the correction module 35 of the control unit 9 determines a corrected target setting speed v SOLL of 25 m / s. In the same way, in a further correction module 33 of the control unit 9, based on the amount of the setting head springback travel s RF (or generally: relative travel) and the target setting travel s SOLL a corrected target setting path s KBased on these corrected parameters, a setting signal S F which controls the pressure generator 11.

[0029] In the Fig. 5 shows the setting head 5 at the end of the setting process, in which the setting element 1 is properly driven into the component 3 and the annular collar 19 of the setting element 1 sits on the component surface. List of reference symbols 1 setting element 2 robot arm 3 Component 5 setting head 7 typesetting stamps 9 Control unit 11 Hydraulic unit 13 hydraulic cylinders 15 cylinder pistons 17 Load cell 19 ring bundle 18 Comparator module 21 Sensor device 23 Travel / position sleeve 25 Setting head guide 27 Preload spring 29 Sensor module 31 Element tip 33 first correction module 35 second correction module F SOLL Target setting force s SOLL Target setting path v SOLL Target setting speed s RF Relative path v RF relative speed s K corrected target setting path v K corrected target setting speed F ist Actual setting force F G limit S aus shutdown signal S F Set signal S setting direction R Setting head springback A component evasive movement

Claims

[1] Setting system with a setting head (5) with a stroke-adjustable setting punch (7), which drives a setting element (1) in a setting direction (S) and with a setting force (F) into at least one component (3) in a setting process, and with a control unit (9), which in the setting process on the basis of target setting parameters (F SOLL , s SOLL , v SOLL ) a set signal (S F ) is generated, with which a pressure generator (11, 13) can be controlled, which drives the setting punch (7) over a setting path (s) and at a setting speed (v), wherein the setting system has a sensor device (21) which detects an evasive movement of the setting head (5) and / or an evasive movement (A) of the component (3) during the setting process, wherein the control unit (9) has at least one correction module (33, 35) which, on the basis of the detected evasive movement, generates the setting signal (S F) with which the pressure generator (11, 13) can be controlled, wherein the sensor device (21) is a path / speed detection device, by means of which a relative speed (v RF ) with which the setting head (5) and the component (3) move apart, and wherein a relative path (s RF ) is detectable, via which the setting head (5) and the component (3) move apart in the setting process, characterized by in that the sensor device (21) has at least one sensor element (23) which is mounted on the setting head (5) so as to be adjustable in stroke in the setting direction (S) and which interacts with a sensor module (29) which is fastened to the setting head (5) and which is in signal connection with the control unit (9), wherein the sensor element (29) can move out of the sensor head (5) by a stroke path detected by the sensor module (29). [2] Setting system according to claim 1, characterized bythat the evasive movement of the setting head (5) is a springback (R) of the setting head (5) opposite to the setting direction (S), and that the evasive movement (A) of the component (3) takes place in the setting direction (S). [3] Setting system according to one of the preceding claims, characterized by that a target setting parameter determines the target setting speed (v SOLL ) or a quantity correlating therewith, and that in the correction module (35) on the basis of the detected relative speed (v RF ) and the target setting speed (v SOLL ) a corrected target setting speed (v K ) or a value correlating therewith can be determined, on the basis of which the setting signal (S F ) can be generated. [4] Setting system according to one of the preceding claims, characterized by that a target setting parameter is the target setting path (s SOLL) or a value correlating therewith, and that in the correction module (33) on the basis of the detected relative path (s RF ) and the target setting path (s SOLL ) a corrected target setting path (s K ) or a value correlating therewith can be determined, on the basis of which the setting signal (S F ) can be generated. [5] Setting system according to one of the preceding claims, characterized by that the setting system is an open setting system in which the setting head (5) is not integrated in a C-bracket with a counterholder, but rather the setting head (5) is force-free to a counterholder which is arranged on the component side opposite the setting side. [6] Setting system according to one of the preceding claims, characterized by that the setting system has a setting force detection device (17) by means of which an actual setting force (F ist) can be detected, and that the control unit (9) has a comparator module (18) which determines the actual setting force (F ist ) with a limit value (F G ) and that when compared to the limit value (F G ) significantly larger actual setting force (F ist ) a shutdown signal (S aus ) can be generated, which ends the setting process. [7] Setting system according to one of the preceding claims, characterized bythat at the start of the setting process, the setting head (5) places the setting element (1) on the component surface without deformation, and that at the start of the setting process, the sensor element (23) is also in contact with the component surface, and that during the setting process, the sensor element (23) remains in contact with the component surface, being supported on the component surface under spring preload, so that in the event of a setting head springback (R) and / or a component evasive movement (A), the sensor element (23) moves out of the setting head (5) by a stroke detected by the sensor module (29), which stroke corresponds to the relative path (s RF ) corresponds. [8] Setting system according to claim 7, characterized by that a plurality of sensor elements (23) are arranged distributed in the circumferential direction around the setting axis, or that the sensor element (23) is a travel / position sleeve which is preferably arranged concentrically to the setting axis and / or surrounds the setting punch (7) radially on the outside. [9] Setting system according to one of the preceding claims, characterized by that during the setting process time period (t) the evasive movement parameters relating to the evasive movement (R, A), for example the relative speed (v RF ) and / or the relative path (s RF ), are continuously detectable, and that the setting signal (S F ) based on the evasive movement parameters (v RF , s RF ) is continuously adjustable during the setting process time (t).

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