Vehicle crash determining apparatus

A vehicle crash determining apparatus comprising:

• an acceleration sensor for detecting an impact at a time of crashing of a vehicle;
• a first comparing means for comparing an output signal of said acceleration sensor with a first threshold value;
• a subtracting means for subtracting a predetermined constant value from an output of said first comparing means;
• an integrating means with a reset function for integrating an output of said subtracting means to thereby forcibly reset an integrated value thus obtained to zero when the integrated value falls below zero;
• a second comparing means for determining a necessity of starting an occupant protection means by comparing said integrated value of said integrating means and a second threshold value;
• and
• a starting means for controlling a starting of said occupant protection means based on an output signal of said second comparing means.

A vehicle crash determining apparatus comprising:

• an acceleration sensor for detecting an impact at a time of crashing of a vehicle;
• a first comparing circuit that compares an output signal of the acceleration sensor and a first threshold value;
• an integrating circuit that integrates an output of the first comparing circuit within a predetermined section while making a shift by a unit time;
• a second comparing circuit that determines a necessity of starting an occupant protection device by comparing an integrated value of the integrating circuit with a second threshold value;
• and
• a starting circuit that starts the occupant protection device based on an output signal of the second comparing circuit.