CN115113098A - Cable detector - Google Patents

Abstract

The invention relates to a cable tester (10) having a printed circuit board (12) with an integrated low-voltage and high-voltage measurement technology system (20, 30) for carrying out low-voltage and/or high-voltage testing at a cable (50), wherein the low-voltage and high-voltage measurement technology system (20, 30) comprises at least one switching matrix (25, 35) and the switching elements (26a-26j, 36a-36j) of the switching matrix (25, 35) are formed by semiconductor components.

Description

cable detector

technical field

The present invention relates to cable detectors, cable detector systems, and the use of cable detectors or cable detector systems for electrical detection of cables and/or wire harnesses.

Background technique

Cable testers are used to test circuits. In inspection, it is possible to inspect a single cable or an entire harness. In particular, cable detectors are used in the production of end-of-line automobile manufacturing in automatic bundling lines. Prior art cable detectors are designed to be widely used for inspection of cable bundles and assemblies having a large number of inspection points at the inspection point. The measuring hardware, ie the low-voltage and high-voltage measuring technology systems, are arranged here on various individual measuring cards and can be switched on at each measuring point by means of a relay matrix. All measurement cards are connected via a common measurement bus. Each measurement card has its own control system and communicates with the control module via a bus. The relay matrix consists of motor relays for low ohmic impedance switching in connection or short circuit detection and for electrical isolation from the detection voltage when switching on. Due to the large number, typically 32 or 64 detection points, the large packing density of the matrix can only be achieved with compact repeaters or small repeaters.

However, the high complexity of the multiplexer requires a certain amount of time, for example to switch on multiple relays for establishing the connection between the measuring technology system, the power supply system and the cable to be measured. This time is determined by the on-time of the repeater itself and the waiting time for the so-called "bump" of the contacts in the repeater. In addition, repeaters are subject to wear related to the loading of the contacts during turn-on. Load affects the initial contact resistance and ultimately also the life. Furthermore, when using high voltage detection, the high voltage signal cannot be applied directly to the repeater, but must be continuously increased in time pulses. The connection to the detection point is made via the output of the repeater matrix connected to the cable.

The document DE 10 2016 109 741 A1 relates to an inspection point card device for an inspection table, which is used for inspection of wire harnesses. Here, the detection point card device has a relay circuit and is provided for a plurality of detection points. Voltage applied in the low voltage range between 5V and 24V for cable detection.

The document DE 10 2016 116 695 A1 relates to a method and a measuring device for checking wiring harnesses. A wire harness has multiple wires. An inspection signal is used for inspection, which has a voltage strength of approximately less than or equal to 48V DC or less than or equal to 20V AC.

The demands placed on cables and cables to be produced in large quantities, eg for installation in vehicles, are increasing day by day. Therefore, there is an urgent need for complete measurements, such as using low and high voltages, to perform complete measurements in substantially less time.

SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide a device by which the above-mentioned requirements are met or with its application.

The above objects are achieved by the use of the cable detector according to claim 1 , the cable detector system according to claim 7 and the cable detector or cable detector system according to claim 9 . Further advantageous embodiments of the invention can be derived from the dependent claims, the description and the drawings.

In particular, the above-mentioned objects are achieved by a cable detector having a printed circuit board with an integrated low-voltage and high-voltage measurement technology system for performing the detection of low-voltage and/or high-voltage at the cable , wherein the low-voltage and high-voltage measurement technology system comprises at least one switching matrix, and the switching elements of the switching matrix are formed by semiconductor components.

By arranging all the components necessary for the measurement on the printed circuit board, shorter paths between the components are formed and fewer switching elements are required overall. Faster measurements can be achieved through the resulting faster signal path for communication. Furthermore, the measurement can be carried out with a high-voltage measurement technology system without having to connect additional hardware. This simplifies the structure of the cable detector. A solution in which the switching element consists of semiconductor components enables faster measurements, since these components enable a faster switch-on than conventional repeaters and measurement signals directly.

Preferably, the low and high pressure measurement technology system rests at the detection point. Therefore, a definite parallel detection mode can be achieved by the targeted actuation of the detection points. Finally, individual measurements of each measurement technology system can be implemented at the cable.

Preferably, the number of detection points does not exceed ten. In this case, the number is directly optimized for the detection of the specific cable type. Only the required number of detection points are arranged on the printed circuit board. This makes it possible to realize as simple a circuit as possible with as few switching elements as possible. As a result, faster measurements can be achieved.

Preferably, in the low-voltage measurement technology system, at least each second detection point has its own current source. In particular, a current source is provided for performing measurements of resistance for connection and short-circuit detection. The current source is directly connected to the detection point and thus enables faster measurements.

Preferably, the high-voltage measurement technology system is capable of generating voltages in the range of 0-800V, and the high-voltage measurement technology system is monitored by the safety module. High voltage insulation detection can be achieved by supplying a high voltage. It is thus possible to perform complete measurements with the cable detector, ie measurements with low and high voltages. Safety monitoring according to the standard DIN EN61010-1 can be carried out by means of the safety module. The cable detector is thus validated and certified.

Preferably, the switching elements of the low-voltage and high-voltage measurement technology system comprise transistors. The transistors work losslessly and do not limit the lifetime of the cable detector. In addition, the transistors are switched on faster than so-called repeaters and a direct and virtually power-loss-free digital signal control is possible via the measuring card. Therefore, switching times of less than 1 ms can be achieved. High-voltage-resistant transistors as switching elements enable direct switching of the high voltage to the cable to be detected, whereby measurements can be performed more quickly. In particular, the pulse ramp-up of the high-voltage signal, which is necessary in motor repeaters, is canceled.

Furthermore, in particular, the above objects are achieved by a cable detector system comprising a cable detector and a separate data processing and control device, the data processing and control device being connected to the cable detector, and the data processing and control device being provided with For voltage measurement and control of cable detectors. Cable detectors enable fast measurement of cables. The direct connection of data processing and control equipment enables fast control of cable detectors and fast transfer of data. As a result, shorter measurement cycles can be achieved.

Preferably, the cable detector system also has means for parallel communication, so that the low voltage and high voltage measurement technology systems can respond to the data processing and control device (40) in parallel. Thereby the multiplexer is eliminated and the signal transfer is faster. Furthermore, it is thus possible, for example, to read data from one measuring technology system while the other measuring technology systems are simultaneously ready for measurement. Shorter measurement cycles can be achieved through parallel data processing and control.

Furthermore, in particular, the above object is achieved by the use of a cable detector or cable detector system for electrical detection of cables and/or wire harnesses. Preferably, the cable detector or cable detector system is used in automatic bundling lines in vehicle manufacturing. Shorter measurement periods can be achieved by cable detectors or cable detector systems, wherein complete low and high voltage measurements can be performed. Existing requirements can be met by applying a cable detector or cable detector system, ie a complete measurement cycle can be performed in a shorter time.

Description of drawings

Additional advantages and features of the present invention emerge from the following description of preferred embodiments. The features described below and above can be applied individually or in combination as long as the features are not contradictory. Herein, the following description of the preferred embodiments is given with reference to the accompanying drawings. Shown here:

Figure 1 shows a schematic diagram of an embodiment of a cable detector system with a cable detector and connected cables.

Detailed ways

FIG. 1 shows an embodiment of a cable detector system 1 . The cable detector system 1 comprises at least one cable detector 10 and a data processing and control device 40 . The cable 50 to be detected is connected at the cable detector 10 .

The cable 50 has at least one wire or core suitable for conducting electrical signals. Preferably, the cable 50 is an antenna cable or a sensor cable or a high speed data cable for automobiles. In other embodiments, other cable types can be measured, eg cables with 2 or 4 cores. The cable 50 can be an entire cable, a portion of a cable, or a bundle of wires. The cable 50 is connected to the cable detector 10 via the detection contacts 18 at one or more locations. Preferably, the detection contact 18 is in contact with one end of the cable 50 , while two or more detection contacts 18 are in contact with both sides of the cable 50 . Preferably, the communication of the measurement signals between the printed circuit board 12 of the cable detector 10 and the cable 50 is effected via the input/output device 16 .

In particular, the detection of cables 50 should be applied in automatic cable bundling. Preferably, the cable 50 is sensed every measurement cycle. In an embodiment, the duration of the measurement period using 5 detection points is less than 0.5s.

The cable detector 10 has a printed circuit board 12 on which the complete hardware necessary for the measurement is arranged. The printed circuit board 12 has a low-voltage measuring technology system 20 and a high-voltage measuring technology system 30 . Preferably, the printed circuit board 12 includes a voltage source 14 . In the low voltage measurement technology system 20, at least one of every two detection points 28a-28j has its own current source 24a-24j. Each detection point 28a-28j is connected to its current source 24a-24j via switching elements 26a-26j. The low-voltage measurement technology system 20 is provided for detecting line paths and short circuits between different lines. Preferably, the detection of low voltage is performed at 12V. In the high-voltage measurement technology system 30, the high-voltage module 34 is capable of generating high voltages of up to 800V. The high voltage measurement technology system 30 is provided to detect the insulation resistance and voltage resistance of the cable 50 . Voltage and current measurements can be performed by means of the high-voltage measurement technology system 30 . Preferably, the high voltage detection is performed in the range of 500V-750V. In particular, the high-voltage measurement technology system 30 is protected by a safety module 32 . Preferably, the safety module 32 has a safety logic circuit, an emergency stop device, and an overcurrent detection system. The placement and access of the security module 32 on the printed circuit board 12 cannot be ignored due to its complexity and security requirements. In general, the hardware, in particular the arrangement of the low-pressure measuring technology system 20 and the high-pressure measuring technology system 30, is optimized for short operating paths. Figure 1 is purely schematic. In an alternative embodiment, the components of the high-pressure measurement technology system 30 can be arranged between the components of the low-pressure measurement technology system 20 and vice versa.

The low-voltage measurement technology system 20 and the high-voltage measurement technology system 30 are connected to a cable 50 via detection points 28a-28j, 38a-38j. The number of inspection points 28a-28j, 38a-38j is determined and limited by the cable 50 to be inspected. By means of the limited number of detection points 28a-28j, 38a-38j and the arrangement of the low-voltage measurement technology system 20 and the high-voltage measurement technology system 30 on the printed circuit board 12, the switching element 26a is also reduced and limited relative to conventional cable detectors -26j, the number of 36a-36j. By limiting the number of switching elements 26a-26j, 36a-36j, faster measurements can be achieved. Switching elements 26a-26j, 36a-36j are arranged in switch matrices 25,35. Preferably, the switch matrix 25, 35 also includes detection points 28a-28j, 38a-38j. If a smaller number of detection points 28a-28j, 38a-38j is sufficient to measure other cable types, the detection points can be set by software. Cable detectors 10 can also be cascaded if a greater number of detection points 28a-28j, 38a-38j are required. Preferably, the switching elements 26 a - 26 j , 36 a - 36 j as well as the low-voltage measuring technology system 20 and the high-voltage measuring technology system 30 are controlled by a data processing and control device 40 . The low-voltage measuring technology system 20 and the high-voltage measuring technology system 30 are arranged adjacent to each other and can respond in particular to the data processing and control device 40 in parallel.

The data processing and control device 40 is designed to receive and process the measurement data of the cable detector 10 and to send control signals to the cable detector 10 in order to control the cable detector 10 . Preferably, the data processing and control device 40 has analog and/or digital inputs and outputs and is connected to the cable detector 10 via a cable connection 42 . In a preferred embodiment, the data processing and control device 40 is capable of displaying received and/or processed measurement data on a display device. In another preferred embodiment, the data processing and control device 40 comprises an external PC (personal computer) with an integrated measurement card.

For example, a complete inspection of the antenna line with a state-of-the-art detection system lasts about 1.5 s. The same complete inspection of the antenna line with the embodiment of the line detector system here can be performed in less than 0.5 s.

List of reference signs

1 Cable Detector System

10 Cable detector

12 Printed circuit board

14 Voltage source

16 Input/Output Devices

18 detection contacts

20 Low-voltage measurement technology systems

24a-24j Current Sources

25 switch matrix

26a-26j Switching Elements

28a-28j Inspection Points

30 High-voltage measurement technology systems

32 Security module

34 High Voltage Module

35 switch matrix

36a-36j Switching Elements

38a-38j Inspection Points

40 Data processing and control equipment

42 Cable connections

50 cables.

Claims (9)

1. A cable detector (10) having:

a printed circuit board (12) with an integrated low-voltage and high-voltage measurement technology system (20, 30) for performing low-voltage and/or high-voltage detection at a cable (50); wherein,

the low-voltage measurement technology system (20) and the high-voltage measurement technology system (30) comprise at least one switching matrix (25, 35); and is

The switching elements (26a-26j, 36a-36j) of the switching matrix (25, 35) are formed by semiconductor components.

2. The cable detector (10) of claim 1, wherein the low voltage measurement technology system (20) and the high voltage measurement technology system (30) abut at a detection point (28a-28j, 38a-38 j).

3. The cable detector (10) of claim 2, wherein the number of detection points (28a-28j, 38a-38j) does not exceed 10.

4. The cable detector (10) according to claim 2 or 3, wherein in the low voltage measurement technology system (20) at least one detection point (28a-28j, 38a-38j) of every two detection points has its own current source (24a-24 j).

5. The cable detector (10) according to any of claims 1 to 4, wherein the high voltage measurement technology system (30) is capable of generating a voltage in the range of 0-800V and is monitored by a safety module (32).

6. The cable detector (10) according to any one of claims 1 to 5, wherein the switching elements (26a-26j, 36a-36j) of the low voltage measurement technology system (20) and of the high voltage measurement technology system (30) comprise transistors.

7. A cable detector system (1) comprising:

the cable detector (10) according to any one of claims 1 to 6; and

a separate data processing and control device (40) which is connected to the cable detector (10) and which is provided for voltage measurement and control of the cable detector (10).

8. The cable detector system (1) according to claim 7, further having means for parallel communication to enable the low voltage measurement technology system (20) and the high voltage measurement technology system (30) to respond to the data processing and control device (40) in parallel.

9. Use of a cable detector (10) according to any one of claims 1 to 6 or of a cable detector system (1) according to claim 7 or 8 for electrically detecting a cable (50) and/or a wire harness.

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