Seat wire harness service life test system

Abstract

The invention discloses a seat wire harness life test device, which comprises a mechanical motion subsystem, the mechanical motion subsystem comprises a tank chain, an upper cylinder and a lower cylinder, the lower cylinder is fixed on a stand, and the upper cylinder is fixed above the lower cylinder through a support plate; the tank chain is located on the testing frame, one end of the tank chain is connected with the lower air cylinder, the other end of the tank chain is bent upwards and connected with the upper air cylinder, and a tested wiring harness is located in the tank chain; the environment simulation subsystem comprises a gradient temperature control box; the control and detection subsystem comprises an industrial personal computer and a visual detection module; the visual detection module comprises a high-speed industrial camera and an annular LED light source and aims at the bent part of the wire harness to capture surface defects, the structure is reasonable, repeated bending of the wire harness can be achieved in different temperature environments through simple equipment, and therefore the service life of the wire harness is tested.

Description

Technical Field

[0001] The present invention relates to the field of wire harness testing, and in particular to a seat wire harness life testing system. Background Art

[0002] The automotive wiring harness is the network backbone of the vehicle's electrical circuits. Without it, there would be no automotive circuits. A wiring harness is a component that connects electrical circuits by crimping copper contact terminals with wires and cables, then wrapping them with plastic-molded insulation or a metal casing.

[0003] Most wiring harnesses retain their shape after installation. However, wiring harnesses used in car seats experience changes in their bendability with every seat adjustment. This requires ensuring a sufficient lifespan for the wiring harnesses. Testing the lifespan of wiring harnesses in various environments is a current research and development area. The following proposes a solution to this problem. Summary of the Invention

[0004] The purpose of the present invention is to provide a seat harness life test system, which has the advantage of being able to perform bending tests on the harness at various temperatures, thereby testing the service life of the harness in an actual environment.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: A seat harness life test device, comprising: A mechanical motion subsystem, comprising a tank chain and two cylinders, the two cylinders being divided into an upper cylinder and a lower cylinder, the two cylinders being arranged horizontally and on the same vertical plane, the lower cylinder being fixed on a platform, and the upper cylinder being fixed above the lower cylinder via a support plate; The tank chain is located on the test stand. A fixing block is provided at the ends of the two cylinders. One end of the tank chain is connected to the fixing block at the end of the lower cylinder. The other end of the tank chain is bent upward and connected to the fixing block of the upper cylinder. The wiring harness to be tested is located inside the tank chain. An environmental simulation subsystem, comprising a gradient temperature control box, comprising a temperature control chamber and a temperature control layer. The temperature control layer is divided from top to bottom into a high-temperature layer, a transition layer, and a low-temperature layer, the layers being separated by air curtains. The temperature control layer is used to regulate the temperature in the temperature control chamber; The inner wall of the high-temperature layer is provided with an infrared radiation heating array; the low-temperature layer is embedded with a Peltier semiconductor refrigeration sheet; the transition layer is equipped with a circulating fan unit; Temperature sensors are provided in the high temperature layer, transition layer and low temperature layer, and the temperature sensors include thermocouples and infrared thermometers; The test stand and tank chain are both located in a temperature-controlled room; A control and detection subsystem, comprising an industrial computer and a visual detection module; The industrial computer has a built-in PLC controller, which is connected to the two cylinders and the gradient temperature control box via the EtherCAT bus; The visual inspection module includes a high-speed industrial camera and a ring-shaped LED light source, which is aimed at the bending parts of the wire harness to capture surface defects.

[0006] Preferably, a test method for a seat harness life test device is characterized in that: S1: Parameter configuration Set the temperature cycle curve: high temperature holding stage T1, low temperature holding stage T2, temperature rise stage ΔT↑, temperature drop stage ΔT↓; Set mechanical motion parameters: horizontal displacement D, motion speed V; S2: Dynamic coupling test In the temperature rise stage ΔT↑, the first motion mode is synchronously executed: D=300mm, V=10mm / s; During the high temperature maintenance stage T1, switch to the second motion mode: D = 400 mm, V = 20 mm / s; During the temperature drop phase ΔT↓, the system switches to the third motion mode: D=300mm, V=15mm / s. In the low temperature holding stage T2, switch to the fourth motion mode: D = 300 mm, V = 20 mm / s; A test cycle starts from the temperature rise stage ΔT↑ and ends at the low temperature holding stage T2; S3 online evaluation phase: After each N cycles, the wiring harness is tested for on-resistance (test current 1A) and insulation withstand voltage test DC500V for 60s. When the resistance change rate is greater than 5% or the insulation resistance is less than 100MΩ, the wiring harness is deemed to be faulty and the test is terminated; During the test phase, if the wiring harness is damaged, the wiring harness is deemed to have failed and the test is terminated.

[0007] Preferably, in step S2, the temperature of the low-temperature holding stage T2 is -20°C~0°C; the temperature range of the high-temperature holding stage T1 is 60°C~80°C; the temperature change rate of the temperature rise stage ΔT↑ is 12°C / min; the temperature change rate of the temperature drop stage ΔT↓ is 15°C / min; and the tolerance of the temperature change rate is ±10%.

[0008] Preferably, a protection time t is set between the temperature change stage and the mechanical movement switching interval, 0.5s≤t≤2s; During the high temperature holding stage T1, random vibration excitation is superimposed, and the vibration spectrum density is 0.04g 2 / Hz, frequency range 5~500Hz.

[0009] Preferably, a seat harness life test system is characterized by comprising a timing synchronization control module and a fault prediction module. The timing synchronization control module ensures that the time deviation between the displacement starting point and the temperature change stage starting point is ≤0.1s by establishing a timestamp alignment mechanism between the mechanical movement and the temperature cycle; The timing synchronization control module dynamically adjusts the acceleration curves of the output shafts of the two cylinders according to the temperature layer switching state to avoid mechanical resonance caused by temperature gradient; The fault prediction module is used to build an LSTM neural network model, the input layer contains time series tension data, temperature fluctuation value, resistance change rate, and the output layer predicts the remaining life; When the fault prediction module predicts that the remaining life is lower than a threshold, the data sampling frequency is automatically increased to 10 kHz for fine monitoring.

[0010] Preferably, the timing synchronization control module adopts the IEEE 1588 precise time protocol to achieve multi-device clock synchronization; the fault prediction module integrates the SHAP explanatory analysis component to visually display the contribution of each parameter to the life prediction test tooling.

[0011] The beneficial effects of the present invention are: (1) Improving the aging rate of wiring harnesses by coupling horizontal displacement and wide temperature range cycling (-40°C to 80°C); (2) Through asymmetric temperature change control (heating 12℃ / min, cooling 15℃ / min), the time of a single temperature change cycle is shortened, saving 27% energy compared with the traditional symmetric temperature change scheme; (3) The visual inspection module has a detection rate of 99.2% for wire harness surface cracks, and a false alarm rate of <0.5%; The LSTM life prediction model has a remaining life estimation error of ≤8% in 1,000 sets of test data. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural diagram of an embodiment; Figure 2 Schematic diagram of the side structure of the embodiment; Figure 3 This is a cross-sectional view of an embodiment used to illustrate the internal structure of a gradient temperature control box.

[0013] Figure numerals: 1. upper cylinder; 2. lower cylinder; 3. stand; 4. support plate; 5. test frame; 6. fixing block; 7. tank chain; 8. gradient temperature control box; 9. temperature control room; 10. high temperature layer; 11. transition layer; 12. low temperature layer; 13. infrared radiation heating array; 14. Peltier semiconductor refrigeration plate; 15. circulating fan unit. DETAILED DESCRIPTION

[0014] The following is only a preferred embodiment of the present invention, and the scope of protection is not limited to this embodiment. All technical solutions under the concept of the present invention should fall within the scope of protection of the present invention. The same parts are represented by the same figure marks. It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to the directions in the accompanying drawings, and the words "bottom" and "top", "inside" and "outside" refer to the directions toward or away from the geometric center of a specific component, respectively.

[0015] A seat harness life test device comprises a mechanical motion subsystem, an environmental simulation subsystem and a control and detection subsystem.

[0016] The mechanical motion subsystem includes a tank chain 7 and two cylinders. The two cylinders are arranged on the platform 3. The tank chain 7 is arranged on a test frame 5 on one side of the platform 3. The test frame 5 is located in the environmental simulation subsystem.

[0017] The two cylinders are arranged horizontally and on the same vertical plane, divided into an upper cylinder 1 and a lower cylinder 2. The lower cylinder 2 is fixed to a stand 3, and the upper cylinder 1 is fixed directly above the lower cylinder 2 via a support plate 4. To facilitate the connection of the cylinder output shafts to the tank chain 7, fixing blocks 6 are installed at the ends of the output shafts of both cylinders. The fixing blocks 6 have holes for connecting to the ends of the tank chain 7, which can be fixed to the tank chain 7 using fasteners such as screws.

[0018] One end of the tank chain 7 is connected to the fixed block 6 at the end of the lower cylinder 2, and the other end of the tank chain 7 is bent upward and connected to the fixed block 6 of the upper cylinder 1. The wiring harness to be tested is located inside the tank chain 7.

[0019] The environmental simulation subsystem includes a gradient temperature control box 8, which includes a temperature control chamber 9 and a temperature control layer. The temperature control layer is located on one side of the temperature control chamber 9 and is used to regulate the temperature within the temperature control chamber 9. The entire wiring harness under test and the tank chain 7 are located within the temperature control chamber 9. Sensors are installed within the temperature control chamber 9 to display the internal temperature.

[0020] The temperature control layer is divided from top to bottom into a high-temperature layer 10, a transition layer 11, and a low-temperature layer 12. These layers are separated by air curtains to prevent them from interfering with each other. The inner wall of the high-temperature layer 10 is equipped with an infrared radiation heating array 13, which can quickly increase the temperature within the temperature-controlled chamber 9. The low-temperature layer 12 is embedded with Peltier semiconductor cooling plates 14 to reduce the temperature within the temperature-controlled chamber 9. The transition layer 11 is equipped with a circulating fan unit 15, which continuously blows air into the temperature-controlled chamber 9 to maintain room temperature.

[0021] Temperature sensors are provided in the high-temperature layer 10, the transition layer 11 and the low-temperature layer 12. The temperature sensors include thermocouples and infrared thermometers. The temperature sensors can detect the temperatures in the three temperature control layers and can adjust the temperature in the temperature control chamber 9 more accurately.

[0022] The control and inspection subsystem includes an industrial computer and a visual inspection module. The industrial computer has a built-in PLC controller, which is connected to two cylinders and a gradient temperature control box via the EtherCAT bus. The visual inspection module includes a high-speed industrial camera and a ring-shaped LED light source, which is aimed at the curved parts of the wire harness to capture surface defects.

[0023] A test method for a seat harness life test device, S1: Parameter configuration Set the temperature cycle curve: high temperature holding stage T1, low temperature holding stage T2, temperature rise stage ΔT↑, temperature drop stage ΔT↓; Set mechanical motion parameters: horizontal displacement D, motion speed V; S2: Dynamic coupling test In the temperature rise stage ΔT↑, the first motion mode is synchronously executed: D=300mm, V=10mm / s; During the high temperature maintenance stage T1, switch to the second motion mode: D = 400 mm, V = 20 mm / s; During the temperature drop phase ΔT↓, the system switches to the third motion mode: D=300mm, V=15mm / s. In the low temperature holding stage T2, switch to the fourth motion mode: D = 300 mm, V = 20 mm / s; A test cycle starts from the temperature rise stage ΔT↑ and ends at the low temperature holding stage T2; The temperature of the low temperature holding stage T2 is -20℃~0℃, that is, when it is below 0℃, it is the low temperature holding stage T2; the temperature range of the high temperature holding stage T1 is 60℃~80℃, that is, when it is above 60℃, it is not the high temperature holding stage T1.

[0024] The temperature change rate of ΔT↑ in the temperature rise stage is 12℃ / min; the temperature change rate of ΔT↓ in the temperature drop stage is 15℃ / min; the tolerance of the temperature change rate is ±10%.

[0025] S3 online evaluation phase: After each N cycles, the harness conduction resistance is measured with a test current of 1A, and an insulation withstand voltage test of DC500V is performed for 60s. When the resistance change rate is greater than 5% or the insulation resistance is less than 100MΩ, the wiring harness is deemed to be faulty and the test is terminated; During the test phase, if the wiring harness is damaged, the wiring harness is deemed to have failed and the test is terminated.

[0026] The protection time t is set between the temperature change stage and the mechanical movement switching interval, 0.5s≤t≤2s; During the high temperature holding stage T1, random vibration excitation is superimposed, and the vibration spectrum density is 0.04g 2 / Hz, frequency range 5~500Hz.

[0027] A seat harness life test system includes a timing synchronization control module and a fault prediction module. The timing synchronization control module establishes a timestamp alignment mechanism between mechanical motion and temperature cycle to ensure that the time deviation between the displacement starting point and the temperature change stage starting point is ≤0.1s; The timing synchronization control module dynamically adjusts the acceleration curves of the two cylinder output shafts according to the temperature layer switching status to avoid mechanical resonance caused by temperature gradient; The fault prediction module is used to build an LSTM neural network model. The input layer contains time-series tension data, temperature fluctuation values, and resistance change rate, and the output layer predicts the remaining life. When the fault prediction module predicts that the remaining life is lower than the threshold, it automatically increases the data sampling frequency to 10kHz for fine monitoring.

[0028] The timing synchronization control module adopts the IEEE 1588 precise time protocol to achieve multi-device clock synchronization; the fault prediction module integrates the SHAP explanatory analysis component to visually display the contribution of each parameter to the life prediction of the test tooling.

[0029] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A seat harness life test device, characterized in that: include: A mechanical motion subsystem, the mechanical motion subsystem includes a tank chain (7) and two cylinders, the two cylinders are divided into an upper cylinder (1) and a lower cylinder (2), the two cylinders are arranged horizontally and on the same vertical plane, the lower cylinder (2) is fixed on a platform (3), and the upper cylinder (1) is fixed above the lower cylinder (2) through a support plate (4); The tank chain (7) is located on the test frame (5), and the ends of the two cylinders are both provided with fixed blocks (6). One end of the tank chain (7) is connected to the fixed block (6) at the end of the lower cylinder (2), and the other end of the tank chain (7) is bent upward and connected to the fixed block (6) of the upper cylinder (1). The wiring harness to be tested is located inside the tank chain (7); An environmental simulation subsystem, the environmental simulation subsystem comprising a gradient temperature control box (8), the gradient temperature control box (8) comprising a temperature control chamber (9) and a temperature control layer, the temperature control layer being divided from top to bottom into a high temperature layer (10), a transition layer (11) and a low temperature layer (12), the layers being separated by air curtains, the temperature control layer being used to adjust the temperature in the temperature control chamber (9); The inner wall of the high-temperature layer (10) is provided with an infrared radiation heating array (13); the low-temperature layer (12) is embedded with a Peltier semiconductor refrigeration sheet (14); and the transition layer (11) is equipped with a circulating fan unit (15); Temperature sensors are provided in the high-temperature layer (10), the transition layer (11) and the low-temperature layer (12), and the temperature sensors include thermocouples and infrared thermometers; The test stand (5) and the tank chain (7) are both located in a temperature-controlled room (9); A control and detection subsystem, comprising an industrial computer and a visual detection module; The industrial computer has a built-in PLC controller, which is connected to the two cylinders and the gradient temperature control box via the EtherCAT bus; The visual inspection module includes a high-speed industrial camera and a ring-shaped LED light source, which is aimed at the bending parts of the wire harness to capture surface defects.

2. The test method of a seat harness life test device according to claim 1, characterized in that: S1: Parameter configuration Set the temperature cycle curve: high temperature holding stage T1, low temperature holding stage T2, temperature rise stage ΔT↑, temperature drop stage ΔT↓; Set mechanical motion parameters: horizontal displacement D, motion speed V; S2: Dynamic coupling test In the temperature rise stage ΔT↑, the first motion mode is synchronously executed: D=300mm, V=10mm / s; During the high temperature maintenance stage T1, switch to the second motion mode: D = 400 mm, V = 20 mm / s; During the temperature drop phase ΔT↓, the system switches to the third motion mode: D=300mm, V=15mm / s. In the low temperature holding stage T2, switch to the fourth motion mode: D = 300 mm, V = 20 mm / s; A test cycle starts from the temperature rise stage ΔT↑ and ends at the low temperature holding stage T2; S3 online evaluation phase: After each N cycles, the wiring harness conduction resistance measurement and insulation withstand voltage test are performed at DC500V for 60 seconds. When the resistance change rate is greater than 5% or the insulation resistance is less than 100MΩ, the wiring harness is deemed to be faulty and the test is terminated; During the test phase, if the wiring harness is damaged, the wiring harness is deemed to have failed and the test is terminated.

3. The testing method of a seat harness life test device according to claim 2, characterized in that: In step S2, the temperature of the low-temperature holding stage T2 is -20°C to 0°C; the temperature range of the high-temperature holding stage T1 is 60°C to 80°C; the temperature change rate of the temperature rise stage ΔT↑ is 12°C / min; the temperature change rate of the temperature drop stage ΔT↓ is 15°C / min; and the tolerance of the temperature change rate is ±10%.

4. The testing method of a seat harness life test device according to claim 2, characterized in that: The protection time t is set between the temperature change stage and the mechanical movement switching interval, 0.5s≤t≤2s; During the high temperature holding stage T1, random vibration excitation is superimposed, and the vibration spectrum density is 0.04g 2 / Hz, frequency range 5~500Hz.

5. The seat harness life test system according to claim 1, characterized in that: Including timing synchronization control module and fault prediction module, The timing synchronization control module ensures that the time deviation between the displacement starting point and the temperature change stage starting point is ≤0.1s by establishing a timestamp alignment mechanism between the mechanical movement and the temperature cycle; The timing synchronization control module dynamically adjusts the acceleration curves of the output shafts of the two cylinders according to the temperature layer switching state to avoid mechanical resonance caused by temperature gradient; The fault prediction module is used to build an LSTM neural network model, the input layer contains time series tension data, temperature fluctuation value, resistance change rate, and the output layer predicts the remaining life; When the fault prediction module predicts that the remaining life is lower than a threshold, the data sampling frequency is automatically increased to 10 kHz for fine monitoring.

6. A seat harness life test system according to claim 5, characterized in that: The timing synchronization control module adopts the IEEE 1588 precise time protocol to achieve multi-device clock synchronization; the fault prediction module integrates the SHAP explanatory analysis component to visually display the contribution of each parameter to the life prediction of the test tooling.

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