Test device for a contact of an electrical line and method for operating a test device
The test device with a contact centering mechanism and stationary camera optimizes the positioning of test modules to reduce complexity and cycle time, facilitating efficient electrical and optical inspection of multiple contacts in cable assemblies.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MD ELEKTRONIK GMBH
- Filing Date
- 2025-10-15
- Publication Date
- 2026-05-15
AI Technical Summary
Existing electrical and optical testing devices for electrical contacts in cable assemblies require high engineering effort and have long cycle times due to complex equipment and inefficient testing processes.
A test device with a contact centering mechanism that holds the electrical contact stationary, combined with a stationary camera and movable electrical and optical test modules, allowing for simultaneous and efficient testing of multiple contacts.
Reduces equipment complexity and significantly shortens the cycle time for testing electrical contacts by optimizing the movement and positioning of test modules, enabling rapid and thorough inspection of multiple contacts.
Smart Images
Figure EP2025079737_15052026_PF_FP_ABST
Abstract
Description
[0001] Test device for a contact of an electrical line and method for operating a test device
[0002] Description
[0003] Technical field
[0004] The present disclosure relates to a test device for an electrical contact of an electrical line to be tested, wherein the test device comprises an electrical test module and an optical test module, wherein the optical test module comprises a stationary camera, and wherein the electrical contact to be tested is movable along a delivery axis to a stationary test position.
[0005] Background of the Revelation
[0006] In cable assembly, contacts are attached to electrical conductors, for example, by crimping. It is well known that these contacts must be tested. This involves, firstly, fundamentally physical aspects, namely whether the correct contact is attached and whether it is undamaged. In particular, it is important to check whether the contact tip of an inner conductor contact is correctly positioned relative to the outer conductor contact. Within the outer conductor's sleeve, the inner conductor contact should be aligned essentially along the sleeve's axis, in a straight line, and at a defined distance from the sleeve's edge. Secondly, it is important to check whether the various sub-contacts of the connector are correctly and electrically connected to the corresponding conductors of the cable.
[0007] State of the art
[0008] It is known from the prior art to optically detect and inspect both ends of an electrical cable clamped in a respective cable clamp. It is also known to determine electrical characteristics, such as the breakdown voltage between the inner and outer conductor contacts.
[0009] Document JP S57144474 A describes a test device for the interface of a contact and an electrical conductor, in which a high voltage is applied via an electrode to detect a breakdown voltage. Prior to this, an optical inspection is performed using a light source and a photodetector.
[0010] Chinese utility model CN 209487915 U describes a precise testing device for a coaxial connector for a car camera, in which the test device includes a rotary table on which the cable to be tested is placed. A CCD camera performs an optical inspection after an electrical parameter has been measured.
[0011] A disadvantage of electrical and optical testing devices is that the equipment engineering effort is very high and that the cycle time required for this test of a contact is long.
[0012] Brief description of the Revelation
[0013] The purpose of the present disclosure is to provide an electrical and optical testing device whose technical complexity is reduced while simultaneously shortening the cycle time required for testing a contact.
[0014] This problem is solved with regard to the test device with the combination of features of claim 1 and with regard to the method with the combination of features of claim 10.
[0015] In a device of this type, this problem is solved according to the invention by the fact that the test device has a contact centering mechanism by means of which the electrical contact to be tested is held stationary in the test position, and that the test position is in focus of the camera, while at least components of the two test modules can be moved successively into a respective working position in which the respective test module is in operative connection with the electrical contact to be tested, which is held stationary in the test position.
[0016] The test device according to the disclosure is designed and configured for testing an electrical contact, e.g., a plug with multiple partial contacts at the end section of an electrical conductor. For this purpose, the test device comprises an electrical test module and an optical test module, the optical test module including a stationary camera and preferably a lighting unit. The contact is movable along a feed axis to a stationary test position, in particular by means of a conductor clamp movable along the feed axis. The test device has a contact centering mechanism by means of which the contact can be fixed in the stationary test position, while at least components of the two test modules can be moved successively into a respective working position. The respective working position is characterized by the fact that the respective test module is in operative connection with the contact, which is at rest in the test position.In a particularly preferred embodiment, the electrical test module is fully movable into its working position, while in the case of the optical test module, (only) its illumination unit is movable into its working position, while its camera remains stationary. The stationary test position is in focus of the stationary camera. The term "stationary" means "immovably attached to a frame or stand of the test device" and can also be described as "stationary." This reduces the complexity of the device design while simultaneously shortening the cycle time.
[0017] Preferably, a light barrier or light curtain is arranged along the feed axis adjacent to the contact centering mechanism on a side of the contact centering mechanism facing away from the working positions of the test modules. The light curtain can also be referred to as a light band. It creates an area whose penetration by an end face of the contact is detected at any point on the area. Thus, the light barrier or light curtain is adjacent to the contact centering mechanism in the direction of feed. An electronic control unit is designed and configured to move the contact, during the feed movement, from the activation of the light barrier or light curtain by a predetermined feed distance in the feed direction to the test position of the contact.In a particularly preferred embodiment, the contact centering device has two clamping jaws that are movable transversely to the feed axis on both sides towards the contact in order to fix it in its test position and hold it in place.
[0018] The two clamping jaws can each have two legs and be, for example, L-shaped, so that in the closed state of the contact centering, the two clamping jaws form an all-around clamping frame. A particularly preferred arrangement is one in which each clamping jaw has several gripper jaws spaced apart from each other in the feed direction. This ensures that the contact, or the section of the conductor adjacent to the contact, is held particularly securely without requiring excessive clamping forces that could deform the contact, and in particular, the straight alignment of the conductor in the feed direction is maintained.
[0019] The working position of the electrical test module is preferably located on the feed axis. From there, the electrical test module can be moved (retracted) to a waiting position, which is also located on the feed axis, with the working position situated between the stationary test position of the contact and the waiting position. This allows the electrical test module to wait in its current position, close to its working position and thus also close to the test position of the contact, until the feed movement is complete and the contact is centered. It can then move along the feed axis (against the feed direction) from the waiting position to the working position, taking the shortest possible path.
[0020] The paths of the test modules or their moving components, and thus the cycle time of the contact test, can be further reduced if the electrical test module can be moved into an alternative position that is arranged at the waiting position, spaced transversely to the delivery axis.
[0021] The cycle time for contact testing can be further reduced if the camera is stationary on the feed axis, if an optical axis of the camera is directed along the feed axis towards the test position, and if the test position of the contact is spaced from the camera such that the contact (e.g., its end face facing away from the conductor) is in focus. In a particularly preferred embodiment, the optical test module includes a lighting unit that forms the movable component of the optical test module. In this embodiment, the optical test module is already in the aforementioned operative connection with the contact when the lighting unit has been moved into its working position. The camera can be stationary and does not need to be moved. This further reduces the equipment complexity while simultaneously shortening the cycle time.
[0022] The evaluation of the camera image can be facilitated and the optical inspection further improved if the lighting unit has an internal through-hole surrounded by light sources, e.g., in the form of an LED lighting ring. In this case, the through-hole is located on the feed axis when the lighting unit is in its operating position.
[0023] Preferably, the through-hole is arranged between the contact's test position and the camera, so that the illumination unit is positioned very close to the contact, thus brightly illuminating it, and the camera captures its image through the through-hole. This facilitates the evaluation of the camera image and improves the optical inspection.
[0024] The number of actuators, and thus the complexity of the device, can be further reduced if the lighting unit and the electrical test module are mechanically coupled such that the lighting unit is in its operating position when the electrical test module is in its backup position, and the lighting unit is in a backup position when the electrical test module is in its standby position. The backup position of the lighting unit is arranged laterally or transversely to the feed axis. This coupling is particularly preferably formed by a common support component, e.g., a common support plate arranged perpendicular to the feed direction. The common support component is then movable transversely to the feed direction by a common actuator, e.g., a common cylinder.Preferably, the lighting unit and the electrical test module are mechanically coupled to each other in such a way that the lighting unit is arranged in the backup position even when the electrical test module is in its operating position. For this purpose, an actuator can be provided which is attached to the common support component and can move the electrical test module relative to the common support component along the delivery axis.
[0025] Also disclosed is a test device in which the previously described test device is duplicated, and in which both contacts of a conductor can be tested simultaneously. This more than halves the required testing time for the two contacts of a conductor. Furthermore, additional continuity tests can be performed during the electrical test, covering the entire conductor with its two contacts.
[0026] The invention also relates to a method for operating a test device such as the one presented here.
[0027] The method according to the invention is preferably used for operating a test device as disclosed and comprises the following steps:
[0028] - Moving the contact along the delivery axis in the delivery direction towards the light barrier or light curtain;
[0029] - Detection of the activation of the light barrier or light curtain by the control unit;
[0030] - Moving the contact further in the delivery direction along a predetermined delivery path;
[0031] - Activating the contact centering and holding the contact in a fixed position;
[0032] - Moving the electrical test module along the delivery axis against the delivery direction from the waiting position to the working position;
[0033] - Performing the electrical test;
[0034] - Retracting the electrical test module along the delivery axis in the delivery direction back to the waiting position;
[0035] - Moving the electrical test module from the waiting position to the alternative position perpendicular to the delivery axis and simultaneously moving the lighting unit of the optical test module from the alternative position to the working position perpendicular to the delivery axis;
[0036] - Performing the optical inspection using the optical inspection module.
[0037] This method also achieves a reduction in the cycle time of the contact test with reduced equipment requirements.
[0038] The cycle time can be further reduced if, while moving the electrical test module from its waiting position to its backup position (perpendicular to the feed axis), the coupled lighting unit is simultaneously moved from its backup position (perpendicular to the feed axis) to its working position. This simultaneity is preferably achieved by activating a common actuator.
[0039] In a particularly preferred embodiment of the method, the aforementioned steps are performed simultaneously at two contacts of two conductor ends of a single conductor. This more than halves the required testing time for the two contacts of a conductor and allows for further electrical tests to be carried out.
[0040] The electrical test preferably includes a continuity test, a short-circuit test (e.g. with low voltage) and an insulation test (e.g. with 750 volts).
[0041] The optical inspection preferably includes checking the presence and correct positioning of various partial contacts (e.g., inner contact and outer contact) of the contact to be tested.
[0042] Further advantages and features of the disclosure will become apparent from the dependent claims and from the following description of preferred embodiments.
[0043] Brief description of the figures Below, an embodiment of the present disclosure in terms of device engineering and process engineering is described on the basis of the associated figures.
[0044] Fig. 1 shows the essential parts of an embodiment of the test device in a side view;
[0045] Fig. 2 shows a section of the test device from Fig. 1 in a different operating state in a perspective view;
[0046] Fig. 3 shows the essential parts of the exemplary embodiment of the test device in the operating state according to Fig. 2 in a side view;
[0047] Fig. 4 shows the essential parts of the exemplary embodiment of the test device from Figs. 1 to 3 in a different operating state in a side view; and
[0048] Fig. 5 shows an embodiment of the method.
[0049] Description of the exemplary implementations
[0050] Fig. 1 shows the essential parts of the exemplary embodiment of the test device in a side view. It depicts an operating state of the test device in which an electrical test module 1 is in a standby position, while an illumination ring 2 of an optical test module 3 is in a backup position, which can also be referred to as a park position.
[0051] Apart from the movable illumination ring 2, the optical inspection module 3 also includes a stationary camera 4, whose optical axis 6 coincides with a feed axis 6 of the inspection device and is therefore simply referred to as axis 6 in the following. An electrical contact, which has been previously crimped to an end section of an electrical conductor (neither of which are shown), can be moved along axis 6 in the feed direction Y (from left to right in Fig. 1) and fixed at a defined point on axis 6 by means of a contact centering device 8. This point is called inspection position 10.
[0052] The electrical test module 1 can then be moved from the waiting position shown in Fig. 1 along axis 6 against the direction of travel Y (from right to left in Fig. 1) into its working position. In the working position, the electrical test module 1 comes into mechanical and thus electrically conductive contact with the contact.
[0053] Fig. 2 shows a section of the exemplary embodiment of the test device from Fig. 1 in a perspective view.
[0054] In this view, a light curtain 12 is clearly visible. During the contact's movement along axis 6, a control unit (not shown) detects that the end face of the contact leading in the direction of movement has reached the light curtain 12. From this point, the contact is moved a predetermined distance in the direction of movement to reach its test position 10.
[0055] Furthermore, as can be seen in Fig. 2, the contact centering device 8 has clamping jaws arranged on both sides of the axis 6, which are movable transversely to the axis 6 on both sides towards the contact in order to fix it in its test position 10 and hold it in place. Each clamping jaw has several gripper jaws spaced apart from each other in the approach direction Y.
[0056] Fig. 2 shows an operating state of the test device in which the electrical test module 1 is in the working position in which it is connected to the (not shown) contact, while the illumination ring 2 of the optical test module 3 is (compared to Fig. 1) unchanged in the fallback position.
[0057] The operating state shown in Fig. 2 was achieved, starting from the operating state shown in Fig. 1, by attaching the electrical test module 1 to a component 14, which in the illustrated embodiment is formed by an angled plate, and which can be moved by an actuator relative to a common support component 16 parallel to the axis 6. The common support component 16 thus carries, on the one hand, the component 14 with the electrical test module 1 and the actuator, and on the other hand, the lighting ring 2 is attached to the common support component 16.
[0058] In the illustrated embodiment, the common support component 16 is formed by a plate that is arranged perpendicular to the axis 6 and is moved transversely to the axis 6 by an actuator 18.
[0059] In the operating state shown in Fig. 2, the common support component 16 (in Fig. 2 facing upwards) is positioned such that it covers a lens 4a of the camera 4, and that the electrical test module 1 lies on the axis 6, and that the illumination ring 2 (in Fig. 2 above) is placed in its escape position (parking position) at a distance from the axis 6.
[0060] Furthermore, in the operating state shown in Fig. 2, the component 14 (to the right in Fig. 2) has moved in such a way as to counter the feed direction Y that the electrical test module 1 is in its working position.
[0061] Fig. 3 shows the essential parts of the embodiment of the test device according to Fig. 1 in the operating state from Fig. 2.
[0062] In the operating state shown in Figures 2 and 3, the electrical test can be performed when a corresponding contact is fixed in its test position 10. In the illustrated embodiment, the electrical test comprises a continuity test, a short-circuit test (e.g., with low voltage), and an insulation test (e.g., with 750 volts).
[0063] Fig. 4 shows the essential parts of the exemplary embodiment of the test device according to Figs. 1 and 3 in an operating state in which the illumination ring 2 of the optical test module 3 is in its working position, while the electrical test module 1 is in a backup position, which can also be referred to as the parking position. This operating state was achieved by first moving the support component 14 with the electrical test module 1 attached to it by the actuator along the axis 6 in the approach direction Y from the working position to the waiting position. Then, the common support component 16 was moved by the actuator 18 transversely to the axis 6 (downwards in Fig. 4).
[0064] In the operating position of the illumination ring 2, its concentric through-hole 2a (shown in Fig. 3) is arranged on the axis 6 such that the camera 4 has a clear view along its optical axis 6. The LEDs of the illumination ring 2 illuminate the end face of the contact, and the camera 4 captures at least one image. This image is electronically evaluated by the control unit and compared with a template.
[0065] In the illustrated embodiment, the optical inspection includes checking the presence and correct positioning of various partial contacts (e.g., inner contact and outer contact) of the contact to be tested.
[0066] Fig. 5 shows the essential steps S1 to S9 of the disclosed method, which can be carried out with the test apparatus according to Figs. 1 to 4. The method comprises the following steps:
[0067] - Moving the contact along the delivery axis 6 in delivery direction Y to the light barrier or light curtain 12 (S1);
[0068] - Detection of the activation of the light barrier or light curtain 12 by the control unit (S2);
[0069] - Moving the contact further along the delivery axis 6 in delivery direction Y by the predetermined delivery path (S3);
[0070] - Activating the contact centering 8 (S4);
[0071] - Moving the electrical test module 1 along the delivery axis 6 against the delivery direction Y from the waiting position to the working position (S5);
[0072] - Performing the electrical test (S6);
[0073] - Retracting the electrical test module 1 along the delivery axis 6 in delivery direction Y to the waiting position (S7);
[0074] - Moving the electrical test module 1 from the waiting position to the escape position and simultaneously moving the lighting ring 2 from the escape position laterally or transversely to the delivery axis 6 (S8);
[0075] - Performing the optical inspection with the stationary camera 4 and the switched-on illumination ring 2 (S9).
[0076] Reference symbol list
[0077] 1 electrical test module
[0078] 2 Component / Lighting Unit / Lighting Ring
[0079] 3 optical inspection modules
[0080] 4 cameras
[0081] 4a Lens
[0082] 6-axis / optical axis / delivery axis
[0083] 8 Contact centering
[0084] 10 test positions
[0085] 12 Light curtain
[0086] 14 Support component (for electrical test module)
[0087] 16 common support component (for electrical test module and lighting ring)
[0088] 18 common actors
[0089] S1 - S9 Step
[0090] Y Delivery direction
Claims
Claims 1. Test device for an electrical contact of an electrical conductor to be tested, wherein the test device comprises an electrical test module (1) and an optical test module (3), wherein the optical test module (3) comprises a stationary camera (4), wherein the electrical contact to be tested is movable along a feed axis (6) to a stationary test position (10), characterized in that the test device has a contact centering (8) by means of which the electrical contact to be tested is held stationary in the test position (10), and that the test position (10) is in focus of the camera (4), while at least components (2) of the two test modules (1, 3) are successively movable into a respective working position in which the respective test module (1, 3) is in operative connection with the electrical contact to be tested held stationary in the test position (10).
2. Test device according to claim 1 with an electronic control unit, characterized in that a light barrier or a light curtain (12) is arranged along the feed axis (6) adjacent to the contact centering on a side facing away from the working positions of the test modules (1 , 3) or the components (2), and that the control unit is designed and configured to move the contact from the activation of the light barrier or the light curtain (12) by a predetermined feed path along the feed axis (6) to the test position (10).
3. Test device according to one of the preceding claims, characterized in that the contact centering (8) has two clamping jaws which are movable on both sides transversely to the feed axis (6) to the stationary test position (10) of the contact or to the contact.
4. Test device according to one of the preceding claims, characterized in that the working position of the electrical test module (1 ) is arranged on the feed axis (6), and that the electrical test module (1 ) is movable into a waiting position which is also arranged on the feed axis (6), wherein the working position is arranged between the stationary test position (10) of the contact and the waiting position.
5. Test device according to claim 4, characterized in that the electrical test module (1 ) can be moved into an alternative position which is arranged at the location of the waiting position laterally or transversely spaced from the delivery axis (6).
6. Test device according to one of the preceding claims, characterized in that the camera (4) is stationary on the feed axis (6), and that an optical axis (6) of the camera (4) is directed along the feed axis (6) towards the test position (10), and that the test position (10) is spaced away from the camera (4) such that the contact is in focus of the camera (4).
7. Testing device according to one of the preceding claims, characterized in that the optical testing module (3) has a lighting unit (2) which forms the component (2) of the optical testing module (3) that can be moved to the working position.
8. Test device according to claim 7, characterized in that the lighting unit (2) has an inner through-hole surrounded by light sources, wherein in the working position of the lighting unit (2) the through-hole is arranged on the feed axis (Y).
9. Test device according to claim 7 or 8, characterized in that the lighting unit (2) and the electrical test module (1) are mechanically coupled to each other such that the lighting unit (2) is in its working position when the electrical test module (1) is in its fallback position, and that the lighting unit is arranged in a fallback position laterally or transversely spaced from the feed axis (6) when the electrical test module (1) is in its standby position.
10. Method for operating a test device, preferably according to claim 2, comprising the steps: 16 / 17 - Moving a contact along a delivery axis (6) in the direction of a light barrier or light curtain (12) (S1 ); - Detecting the activation of the light barrier or light curtain (12) (S2); - Moving the contact along the delivery axis (6) by a predetermined delivery path (S3); - Activating a contact centering and holding the contact in a fixed position (S4); - Moving an electrical test module (1 ) along the delivery axis (6) from a waiting position to a working position (S5); - Performing an electrical test (S6); - Retracting the electrical test module (1 ) along the delivery axis (6) to the waiting position (S7); - Moving the electrical test module (1 ) from the waiting position to an escape position laterally or transversely to the delivery axis (6) and simultaneously moving a lighting unit (2) of an optical test module (3) from an escape position to a working position transversely to the delivery axis (6) (S8); - Performing an optical inspection (S9).