Patent ID: 7540194

Claim:
An ultrasonic sensor for detecting an object, comprising: a substrate; a transmission device for transmitting an ultrasonic wave; a plurality of reception devices for receiving the ultrasonic wave; and a circuit for processing received ultrasonic waves, which are received by the reception devices after the ultrasonic wave transmitted from the transmission device is reflected by the object, wherein the transmission device and the reception devices are integrated into the substrate, the number of the reception devices is equal to or larger than three so that the circuit is capable of detecting an operation failure, each of the transmission device and the three reception devices has a surface for transmitting or receiving the ultrasonic wave, the surface being perpendicular to a ground, the three reception devices are composed of a first to a third reception devices, the first reception device is disposed above the third reception device, and disposed on a left side of the second reception device, the circuit is capable of calculating a horizontal plane distance between the object and the sensor in a horizontal plane parallel to the ground and a horizontal plane direction angle from the sensor to the object in the horizontal plane on the basis of the received ultrasonic waves received by the first and the second reception devices, the circuit is further capable of calculating a vertical plane distance between the object and the sensor in a vertical plane perpendicular to the ground and a vertical plane direction angle from the sensor to the object in the vertical plane on the basis of the received ultrasonic waves received by the first and the third reception devices, and the circuit is capable of checking the horizontal and the vertical plane distances and the horizontal and the vertical plane direction angles on the basis of the received ultrasonic waves received by the second and the third reception devices so that the circuit is capable of detecting the operation failure.