Nine channel safety belt fixing point strength test bench

1： Equipment Introduction:

The nine channel seat belt fixing point strength test bench can conveniently and scientifically achieve the strength test of seat belt fixing points in the standards listed below for light, medium, heavy, passenger, and passenger car seats.

The nine channel seat belt anchorage strength test bench is a testing system used to evaluate the anchorage and seat strength of car seat belts. The equipment uses channel hydraulic cylinders as actuators and adopts fully digital closed-loop real-time control, which can perform position control and force control.

High strength: The platform as a whole has sufficient strength, rigidity, stability, and reliability.

High precision: The installation surface of the test bench is precision machined as a whole to ensure accurate installation positioning and improve the assembly and measurement accuracy of the entire test bench mechanism.

Corrosion resistance: The test bench as a whole has good corrosion resistance, which can prevent it from rusting and operating abnormally in high humidity environments for a long time.

Fatigue strength design: Key components are subjected to strength and stiffness checks to meet fatigue and test bench life design requirements, and to prevent abnormal phenomena such as fatigue fracture and deformation.

Neat appearance: The installation surface of the test bench should be precision machined, and the overall appearance should be easy to clean and beautiful.

Easy installation: The overall structure of the test bench is stable and has strong anti overturning ability. The weight distribution on the platform plane is uniform and stable.

Detail design: All machined parts on the platform are deburred and trimmed to avoid the harm of sharp objects such as sharp corners and edges to personnel.

2： Applicable standards

Meet the testing requirements for static strength of seat belt anchorages in the following standards:

(1) The requirements for the static test of ISOFIX anchor strength in section 5.4 of GB14167-2013 "Installation and Fixing Points for Automotive Safety Belts" and section 5.6 of the standard.

(2) The requirements of section 5.3.2 in GB 15083-2006 "Strength Requirements and Test Methods for Automotive Seats, Seat Anchors, and Headrests".

(3) GB 13057-2014 "Strength of Passenger Car Seats and Their Vehicle Anchors"

(4) The strength test for automotive seat belt anchorages required by ECE R14 FMVSS 207, 210, 225.

(5) Volkswagen EP 84 310.04 EP 84 310.06 EP84 310.08 and related corporate standards.

3、 Equipment composition

The equipment mainly includes the following parts:

Equipment main frame, hydraulic oil source, control cabinet, human body module, measurement and control system and software, cast iron platform, transparent acrylic safety fence with door, etc.

4、 Power supply

AC/single-phase 380 (1 ± 15% VAC/50Hz

1.4 Actuating cylinder

1. There are 9 hydraulic cylinders with a load of 3T and a stroke of 1000mm;

2. Hydraulic cylinder loading speed: Load to the preset output within 2 seconds, with a maximum no-load moving speed of ≥ 320mm/s;

3. Loading force holding time: 0.2s~120s infinitely adjustable;

4. Overshoot error: within ± 1% of the loading target;

5. Synchronization: During the synchronization test, the synchronization error is within ± 1% of the loading target;

6. Control methods: displacement control and load control; Two fully digital closed-loop real-time control methods with disturbance free switching; 9 sets of actuators can be loaded separately or synchronously, and can independently complete measurement, display, and printing in parallel with multiple channels.

7. The servo cylinder adopts a static pressure support sealing form, with good sealing performance, low friction coefficient at low speeds, and low starting power.

8. To facilitate the preparation work for the experiment, a set of remote control operation handles is provided, which can achieve manual remote control operation of all positioning motors.

9. The pushing tool for bus seats meets the strength standard test tool for GB 13057-2014 bus seats and their vehicle fasteners.

⑴ Hydraulic cylinder:

Ø Structural form: Double outlet symmetrical cylinder

Ø Sealing form: Gap sealing (low friction, long life)

⑵ Speed sensor:

Manufacturer: PCB; Model: 3711B122G

Structural characteristics of actuator:

L

The system adopts a clearance device, which automatically centers the force value, reduces lateral force, reduces impact during tensile and compressive tests, and improves the test waveform. The servo linear actuator adopts ball joint support structure at both ends, which greatly reduces the damage to the actuator caused by lateral force from the test piece. The joint support structure adopts modular design, and can be connected to the rear flange after removal. The clearance between the joint support bearings can be adjusted after wear, ensuring the flexible operation of the test system. Structure similar to MTS Corporation 249 in the United States

Swivel Base。

Structural type: double output rod, double action; Referring to the structural characteristics of the servo linear actuator of MTS, a symmetrical four-way servo valve is used to control the design of the symmetrical (asymmetrical) actuator principle.

L

The support of the servo linear actuator piston rod breaks the traditional design, adopts non-metallic support, large clearance design, high lateral force resistance, and has the characteristics of high-speed non sintering self-lubricating. Multi level support combination guiding mechanism, starting pressure less than 0.3MPa, no crawling phenomenon.

The combination seal, high-pressure seal, low-pressure seal, and gap return pipe ensure that the oil cylinder assembly is leak free. The combination sealing structure has good interchangeability and is convenient for maintenance.

L

The displacement sensor adopts the magnetic displacement sensor from MTS company in the United States, which features frictionless motion and true infinite resolution. High precision and reliability, the displacement sensor is built into the piston rod, allowing for flexible movement without external interference.

The actuator piston adopts an integral piston with special heat treatment technology. The piston rod is simply machined with ultra precision, and the surface is chrome plated and polished to achieve R α 0.4u, ensuring high reliability of the actuator.

1.1 hydraulic system

1) The control panel of the pumping station can display parameters such as hydraulic oil temperature, hydraulic oil level, and hydraulic oil pressure of the pumping station unit;

2) Hydraulic oil source filtration accuracy: ≤ 3 microns, with a return oil sample collection port;

3) Equipped with an independent hydraulic source cooling system, using water cooling;

4) The fuel tank and motor base should be equipped with vibration damping pads, and oil immersed motors should be used. The overall noise level during full load operation should be below 75dB (measured at any position in space, 1 meter away from the oil pump);

5) All pressure gauges must be resistant to high pressure and vibration;

6) The hydraulic pump station has two control modes: remote and local;

7) Equipped with an emergency stop device, the system automatically releases load after use.

This system uses a combination of hydraulic pump and accumulator for oil supply. The hydraulic pump only provides the average flow required for vibration, while the excess flow is provided by the accumulator.

The main parameters include working pressure, fuel tank capacity, flow rate, motor power, etc. These parameters need to be selected based on indicators such as the load of the test bench and the movement speed of the workbench.

The hydraulic pump station also has its own electrical control box and protection system, which integrates the control buttons, pressure gauges, protection system warning lights, etc. of the hydraulic pump station. By using the control buttons on the electrical control box, various working states of the hydraulic pump station can be manually controlled, mainly including start, stop, center position, etc.

The protection of the hydraulic pump station itself mainly includes the following points:

Ø Overpressure protection - When the hydraulic system pressure exceeds 21MPa, the overpressure protection warning light will light up and the buzzer will sound;

Overheating protection - When the oil temperature exceeds 60 ℃, the overheating protection warning light will light up and the buzzer will sound;

Ø Oil filter blockage protection - When the pressure oil filter is blocked or the return oil filter is blocked, the oil filter blockage protection warning light will light up and the buzzer will sound;

Ø Emergency stop button - If the system malfunctions, press the emergency stop button to unload the system and reduce the oil pressure to zero.

Structural diagram of hydraulic pump station

Accumulator component

The accumulator component consists of a high-pressure filter, a small accumulator, a one-way valve, and a pressure gauge, as shown in Figure 11. The liquid flow from the electro-hydraulic directional valve of the pump station passes through a 10 µ m high-pressure oil filter, and the clean and pressure stable hydraulic oil enters the servo valve. The servo valve return oil then passes through the one-way valve and accumulator to generate stable back pressure, thereby improving the smoothness of piston movement and reducing waveform distortion. The accumulator needs to be filled with 7MPa of nitrogen gas.

Structural diagram of accumulator

Distributor

The hydraulic distributor, as the interface module between the hydraulic source and the hydraulic cylinder, has the following functions:

⑴ The distributor supplies oil to the actuator;

⑵ Adjust the oil supply pressure of the servo valve pilot valve separately;

⑶ Equipped with emergency cut-off function;

(4) Filter the oil supply of the pilot valve.

The structure and principle of the hydraulic distributor are shown in the diagram.

Hydraulic distributor

Hydraulic pipeline

The pipeline system is designed according to the pressure and flow rate of hydraulic oil. The main content includes:

Oil supply and return pipelines, joints, and pipe clamps;

Ø High pressure hoses can continuously withstand a pressure of 30MPa;

A shut-off valve is installed at the connection between the hydraulic source and the main distributor for easy maintenance;

All hard pipes with a diameter of less than 50mm are made of stainless steel pipes; The remaining pipelines are made of carbon steel pipes, with the outer surface painted and the interior treated with acid washing, neutralization, passivation, and oil coating;

Clean, rinse, and seal before shipping.

1.2 Main frame

1) Each crossbeam on the machine frame is vertically adjusted by driving the lifting mechanism through a remote control motor. Three hydraulic cylinders are installed on each crossbeam, and the distance between the crossbeams is ≤ 290mm;

2) Adjust the actuator on the bottom crossbeam to a distance of ≤ 200mm from the lower point to the test platform;

3) Each hydraulic cylinder can be horizontally adjusted with a minimum spacing of ≤ 290mm and can be locked after adjustment;

4) The weight of each hydraulic cylinder requires a balancing mechanism to eliminate the influence of hydraulic cylinder gravity and adjust the loading angle of the cylinder. The pitch angle range of the hydraulic cylinder is -30 ° to+10 °;

5)

The test bench system adopts a hydraulic servo system, which supplies oil to each channel through a unified oil source and oil separator. The system consists of 9 experimental channels, divided into three groups: upper, middle, and lower, with 3 channels in each group. The upper channel is used for loading the upper body, the middle channel is used for loading the lower body, and the lowest channel is used for loading through the center of mass of the seat. The height of each channel can be adjusted simultaneously, and the left and right directions can be manually adjusted using linear guides separately. Nine loading channels are controlled by hydraulic servo, which can be tested separately or combined into multiple channels for simultaneous loading testing, achieving load synchronization. Each channel contains two control modes: displacement and load. The equipment is equipped with electrical overload protection and load sensor overload protection devices.

Composition: Composed of 1 set of workbench base, 4 columns, 2 side beams, 1 main span beam, 1 horizontal side beam, horizontal loading beam, etc.

1. Provide a multifunctional comprehensive reaction framework for structural testing;

2. The multifunctional comprehensive reaction frame adopts a self balancing concept design;

3. According to different experiments, the hydraulic lifting and lowering of the reaction frame crossbeam can be freely adjusted;

4. Reserve corresponding installation connections for loading equipment and structural specimens;

5. Can resist horizontal reaction forces generated during biased column tests and complex node loading tests.

6. The reaction frame adopts Q345-B structural steel;

7. The upper crossbeam is equipped with an independent lifting system, which makes the lifting operation of the upper crossbeam convenient and safe.

8. The experimental space is large and the height space can be adjusted,

9. The column is in close contact with the base, which can minimize the impact of column elongation on the test results during the testing process. The overall framework construction and each component are subjected to finite element analysis, and the structural optimization design is repeatedly carried out based on the analysis results to achieve satisfactory results.

10. The crossbeam is adjusted in its vertical position by bolts installed on two vertical columns, which is easy to operate. After adjusting to the test position, it is positioned and locked by bolts to eliminate gaps. In order to ensure the stability and safety of the lifting of the crossbeam, reinforced bolts are used to position the lifting crossbeam.

11. The crossbeam is equipped with an independent lifting mechanism, with lifting cylinders fixed on both sides for continuous adjustment of the test space by controlling the lifting of the cylinders.

1.3 sensor

1) Force sensor with 9 ± 3T ranges, load accuracy: 0.5% FS

1.1 Experimental modules and fixtures

1) Three sets of upper body modules

2) Two sets of human body modules (large)

3) 1 set of human body module

4) 3 sets of 20x seat tooling

5) 3 sets of ISOFIX test deformation detection fixtures

6) 9 pieces of 500mm steel wire rope

7) 9 1000mm steel wire ropes

8) 9 pieces of 1500mm steel wire rope

1.2 Hydraulic cylinder position adjustment

1) Electric adjustment of hydraulic cylinder height adjustment;

2) Ensure the minimum gap between each crossbeam through travel switches;

3) Equipped with a remote control to display remote operation.

1.3 control cabinet

1) The control cabinet adopts a standard cabinet, which is beautiful, tidy, and easy to maintain;

2) External aviation plug for easy and quick insertion and removal in the control cabinet;

3) The industrial control computer and data acquisition control components need to be centrally placed in a standard cabinet. The industrial control computer adopts a lower configuration of CPU dual core, 8GB memory, 1TB hard drive, and 19 inch LCD display.

1.4 Software and Control

1) The software automatically controls the experimental process and saves the detection results.

2) The system adopts the Windows platform and can set various testing parameters according to testing standards. It is easy to search for data and curves saved in the database, evaluate and edit test reports.

3) The device has a time control function: the internal force value needs to be synchronized within the specified time and enter the holding phase.

4)

The device has a flexible human-machine interface, Chinese operation, recognition screen representation, and user-friendly interface; It should include functions such as hardware testing, sensor calibration, parameter control, data analysis, etc., and be operated by authorized operators/engineers

5) The test report is standardized, and the output test data is accurate and standardized.

6) Open programs (open standard programs, different control modes, multifunctional test plans)

7) Adopting fully digital closed-loop real-time control, it can perform position control, force control, and smooth transition between force control and position control.

8) Free software upgrade for devices.

Communication and remote control open protocol, capable of remote control, data collection, communication, linkage alarm and recording;

Can be used for synchronous control of multiple machines

1.5 Image data acquisition and storage system

1) It can simultaneously record, store, and replay multiple channels, and can also obtain external trigger signals. Image data acquisition requires a tripod equipped with 2 spotlights to achieve high-quality video recording.

2) Hard disk recorder: 1 set, zoom lens: 3 units

3) Hard disk recorder: Output format:. avi, capable of simultaneously recording multiple channels (3 channels) and playing back multiple channels;

4) Operation interface: 16 bit true color graphical operation interface, screen display: 1/4/8, network video input: digital, 8 * 1080P, image encoding: H.264;

5) Recording mode: manual or automatic, the recording system needs to be connected to the device to achieve automatic triggering

6) Video search: time and place search, calendar search, channel search

7) Backup methods: network backup, USB flash drive, USB portable hard drive

8) Camera: lens zoom 2.8-12mm, horizontal field of view angle: 80 ° -25 °, frame rate of 3 million, 50Hz

9) The control interface and recording system are displayed on separate screens.

1.6 Cast iron platform

The bottom platform is a cast iron platform with longitudinal and transverse T-shaped grooves. The platform is made of high-strength cast iron HT250, which has undergone demagnetization and stability treatment. The platform has high precision and good wear resistance, and the size requirement is not less than 3000mm * 7000mm * 140mm.

1.7 servo valve

Meet loading speed and control requirements. Three level electro-hydraulic servo valve:

Ø Model: SF02 series (pilot valve: Rexroth)