one Electric vehicle helmet Manufacturer's inspection device
It is composed of frame, head type, scale, weight, loading mechanism and simulation lower color device (see Figure 4).
2 Inspection steps
a) Wear the helmet of electric vehicle on the head form, and tie it through the simulated lower face;
b) Apply the initial load according to Table 4, maintain it for 30s, and then determine the initial zero position of the scale;
c) Within 5~10s, add the load to the inspection load specified in Table 4, maintain it for 2min, and then read the elongation indicated by the scale;
d) The inspection results shall be evaluated according to 5.2.5.
Test of crash energy absorption performance of electric vehicle helmet
1. Pretreatment of helmet samples
The manufacturer's samples of electric vehicle helmets must be treated as required before inspection. Select one item for each helmet sample. The helmet samples after high-temperature or low-temperature treatment shall be inspected twice at one place within 5 minutes; For the second inspection, the helmet samples shall be put back into the incubator for more than 20 minutes before inspection. The helmet samples soaked in water shall be dried for 20 min before inspection.
2 Inspection device
It is composed of swing head or drop head crash test bench and test and analysis instrument system. The test bench shall comply with the provisions on ensuring the consistency of collision energy and collision effect.
3 Impact test bench
It is composed of bench, head type, head type fixing frame, lifting and releasing mechanism, anvil, anvil and base, and its main components shall meet the following technical requirements:
a) Head type: It is made of a structure and metal material similar to the frequency response of the human head. The frequency response is flat below 1400Hz, and the minimum resonant frequency is 2500Hz. The head type is divided into small, medium and large models, as shown in Table 6 and Figure 5. The total mass of falling head type (including sensor and connector) is respectively 40+0.1 for small size, 50+0.1 for medium size and 60+0.1kg for large size. Among them, the mass of sensor and connector shall not be more than 25% of the total mass of falling head type.
b) Anvil and anvil base: the anvil is a round flat anvil made of tool steel (T10A), with a diameter of 127 mm and a thickness of more than 15 mm, and the roughness of the impact surface is not less than Ra0 8. The hardness shall not be lower than HRC50. The anvil 'j anvil is rigidly connected. The anvil must be rigidly fixed on the base, and ensure that the impact surface of the anvil is perpendicular to the normal of the head type impact point.
c) Base: made of reinforced concrete, with the base mass not less than 1 6 t。
d) Lifting and releasing mechanism: it is made in a structural form that does not affect the head type (including head type holder) to fall freely after wearing the inspected helmet.
