Occupant detection apparatus
First Claim
1. An occupant detection apparatus comprising:
- a capacitive sensor having an electrode;
a signal applying circuit configured to apply a voltage amplitude signal to the electrode during a first time period and configured not to apply the voltage amplitude signal to the electrode during a second time period, the voltage amplitude signal having a voltage with a varying amplitude;
a signal detector configured to detect a change in an electric current flowing through the capacitive sensor during the first time period; and
a voltage applying circuit configured to apply a predetermined voltage to the electrode during the entire first time period and during at least part of the second time period.
1 Assignment
0 Petitions
Accused Products
Abstract
An occupant detection apparatus includes a capacitive sensor, a signal applying circuit, a signal detector, and a voltage applying circuit. The capacitive sensor has an electrode. The signal applying circuit applies a voltage amplitude signal to the electrode during a first time period, but does not apply the voltage amplitude signal to the electrode during a second time period. The voltage amplitude signal has a voltage with a varying amplitude. The signal detector detects a change in an electric current flowing through the capacitive sensor during the first time period. The voltage applying circuit applies a predetermined voltage to the electrode during the entire first time period and during at least part of the second time period.
-
Citations
17 Claims
-
1. An occupant detection apparatus comprising:
-
a capacitive sensor having an electrode; a signal applying circuit configured to apply a voltage amplitude signal to the electrode during a first time period and configured not to apply the voltage amplitude signal to the electrode during a second time period, the voltage amplitude signal having a voltage with a varying amplitude; a signal detector configured to detect a change in an electric current flowing through the capacitive sensor during the first time period; and a voltage applying circuit configured to apply a predetermined voltage to the electrode during the entire first time period and during at least part of the second time period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. An occupant detection apparatus comprising:
-
a capacitive sensor having an electrode; a signal applying circuit configured to apply a voltage amplitude signal to the electrode during a first time period and configured not to apply the voltage amplitude signal to the electrode during a second time period, the voltage amplitude signal having a voltage with a varying amplitude; and a signal detector configured to detect a change in an electric current flowing through the capacitive sensor during the first time period, wherein the signal applying circuit further includes a frequency modulator for modulating a frequency of the voltage amplitude signal during the first time period.
-
Specification