PERFORMANCE EVALUATION OF THE TANDEM-TYPE AIRBAG SYSTEM

摘要

We have developed a new type of airbag called the tandem-type airbag. The tandem-type airbag consists of two bags vertically connected to each other and penetrated by through holes. During airbag deployment, gas from an inflator first enters into the bag on the steering-wheel-side and then to the passenger-side bag through the holes. It is then released from the vent holes of the passenger-side bag to outside. The passenger-side bag has larger vent holes than those of a conventional airbag, whereas the steering -wheel-side bag has no vent holes. This means that the passenger-side bag can receive the head of the passenger more softly, and the head is held completely at rest by the steering-wheel-side bag. We experimentally evaluated the performance of the tandem-type airbag with regard to airbag injury by measuring the impact acceleration of an impactor falling freely from a height of 5 m onto an airbag inflated by compressed air from gas cylinders. The flow rate of the compressed air was controlled to deflate the airbag just after collision with the impactor. The results of the acceleration measurements showed that the maximum acceleration for the conventional airbag was about 24.6 G, whereas that for the tandem-type airbag was about 14.9-15.7 G. This indicates that the tandem-type airbag can reduce the collision impact by about 30%-40% compared to a conventional airbag.