Object detecting apparatus

摘要

An object detecting apparatus includes a first transmission and reception unit having a first transmitter and a first receiver, a second transmission and reception unit having a second transmitter and a second receiver, and a failure judging section. The first receiver produces a first output signal corresponding to a transmission wave, which is transmitted directly from the second transmitter to the first receiver. The second receiver produces a second output signal corresponding to a transmission wave, which is transmitted directly from the first transmitter to the second receiver. Using at least one of the first output signal and the second output signal, the failure judging section judges whether a failure of the first transmitter or the second receiver has occurred, or judges whether a failure of the first transmission and reception unit or the second transmission and reception unit has occurred.

主权项

1. An object detecting apparatus comprising:
a first transmission and reception unit and a second transmission and reception unit each having a transmitter configured to emit a transmission wave to detect an object in a detection area, and a receiver configured to receive a reflection wave reflected from the object when the transmission wave is applied to the object; a distance detector configured to detect a distance up to the object based on a delay time from a time at which the transmitter emits the transmission wave to a time at which the receiver receives the reflection wave, with respect to each of the first transmission and reception unit and the second transmission and reception unit; and a failure judging section configured to judge whether a failure of the first transmission and reception unit and the second transmission and reception unit has occurred, wherein the failure judging section judges that a failure has occurred in a first transmitter, which is the transmitter of the first transmission and reception unit, or a second receiver, which is the receiver of the second transmission and reception unit, based on a determination that an output signal produced from the second receiver based on the transmission wave that is transmitted directly from the first transmitter to the second receiver is different from a predetermined threshold value through comparison therewith, and wherein each of the first transmission and reception unit and the second transmission and reception unit is au ultrasonic sensor; in a case that the transmitter emits the transmission wave, which is used by the distance detector to detect the distance up to the object, the transmitter emits the transmission wave at same frequency as a resonant frequency of an oscillator of the ultrasonic sensor; and in a case that the transmitter emits the transmission wave, which is used by the failure judging section to judge the occurrence of a failure, the transmitter emits the transmission wave at a frequency lower than the resonant frequency.