Abstract: An ultrasonic transducer includes a transducer case and an ultrasonic element. The transducer case is formed into a bottomed, cylindrical shape having a side plate portion and a bottom plate portion that seals one end side of the side plate portion in an axial direction to configure a diaphragm. The ultrasonic element is fixedly supported to the bottom plate portion to face an interior space surrounded by the side plate portion and the bottom plate portion. The ultrasonic element is arranged in a position being offset in an in-plane direction orthogonal to the axial direction relative to a center position of the diaphragm in the in-plane direction to be capable of generating a first transmission wave having first directivity characteristics and a second transmission wave having second directivity characteristics that are directivity characteristics differing from the first directivity characteristics and in which sound pressure in the axial direction is decreased.

Abstract: An ultrasonic sensor is provided with an ultrasonic element that converts between an electrical signal and an ultrasonic vibration and an element accommodating case having a bottomed cylindrical shape and accommodating the ultrasonic element inside thereof. The element accommodating case includes a side plate portion formed in a cylindrical shape that surrounds a directional center axis, and a bottom plate portion that closes one end side of the side plate portion in an axial direction which is parallel to the directional center axis. The ultrasonic element is attached to the bottom plate portion. The bottom plate portion includes at least one protrusion. The protrusions vibrate together with the bottom plate portion when the bottom plate portion vibrates as an ultrasonic vibration.

Abstract: An ultrasonic transducer includes a transducer case and an ultrasonic element. The transducer case is formed into a bottomed, cylindrical shape having a side plate portion and a bottom plate portion that seals one end side of the side plate portion in an axial direction to configure a diaphragm. The ultrasonic element is fixedly supported to the bottom plate portion to face an interior space surrounded by the side plate portion and the bottom plate portion. The ultrasonic element is arranged in a position being offset in an in-plane direction orthogonal to the axial direction relative to a center position of the diaphragm in the in-plane direction to be capable of generating a first transmission wave having first directivity characteristics and a second transmission wave having second directivity characteristics that are directivity characteristics differing from the first directivity characteristics and in which sound pressure in the axial direction is decreased.

Abstract: A shield member electromagnetically shielding at least part of an electric circuit has a first end and a second end. The first end is configured to be constantly connected to a ground wire to electromagnetically shield at least part of the electric circuit; and the second end is configured to be selectively connectable to a power source, the shield member being configured to generate heat when energized while the second end is connected to the power source. Accordingly, the shield member electromagnetically shielding at least the part of the electric circuit can serve as a heater for preventing freezing and snow attachment.

Abstract: An object detector includes: an acquiring unit that acquires an oscillation signal corresponding to an oscillation of a microphone, the microphone transmitting a transmission wave, which is an ultrasonic wave, on a basis of a driving signal, and being caused to oscillate by a reflected wave generated as a result of the transmission wave being reflected from an object; a fall identifying unit that identifies a fall time point of a first drop from a value more than a threshold to the threshold or less after termination of the driving signal; a rise estimating unit that estimates a rise-in-reverberation time point of the reflected wave, the rise-in-reverberation time point being before the fall time point and after a time point of start of the driving signal; and a distance determining unit that determines a distance to the object on a basis of the rise-in-reverberation time point.

Abstract: An ultrasonic sensor includes an ultrasonic wave transmitting and receiving device, an elastic holding member elastically supporting the ultrasonic wave transmitting and receiving device, and a sensor case housing and holding the elastic holding member. A case cylindrical portion of the sensor case includes an engagement protrusion provided to protrude inward in a radial direction. The elastic holding member includes a support bottom portion in contact with a transmitting-and-receiving-device bottom, an engagement recess provided to be recessed inward in the radial direction and thus house the engagement protrusion, and a leading projection provided at a position corresponding to the engagement recess with respect to a peripheral direction surrounding a central axis line, and provided to protrude from the support bottom portion toward the base-end side in the axial direction. The support bottom portion is formed as a thick portion. The engagement recess is provided in the support bottom portion.

Abstract: An ultrasonic sensor is provided with an ultrasonic element that converts between an electrical signal and an ultrasonic vibration and an element accommodating case having a bottomed cylindrical shape and accommodating the ultrasonic element inside thereof. The element accommodating case includes a side plate portion formed in a cylindrical shape that surrounds a directional center axis, and a bottom plate portion that closes one end side of the side plate portion in an axial direction which is parallel to the directional center axis. The ultrasonic element is attached to the bottom plate portion. The bottom plate portion includes at least one protrusion. The protrusions vibrate together with the bottom plate portion when the bottom plate portion vibrates as an ultrasonic vibration.

Abstract: A shield member electromagnetically shielding at least part of an electric circuit has a first end and a second end. The first end is configured to be constantly connected to a ground wire to electromagnetically shield at least part of the electric circuit; and the second end is configured to be selectively connectable to a power source, the shield member being configured to generate heat when energized while the second end is connected to the power source. Accordingly, the shield member electromagnetically shielding at least the part of the electric circuit can serve as a heater for preventing freezing and snow attachment.

Abstract: An ultrasonic sensor includes an ultrasonic wave transmitting and receiving device, an elastic holding member elastically supporting the ultrasonic wave transmitting and receiving device, and a sensor case housing and holding the elastic holding member. A case cylindrical portion of the sensor case includes an engagement protrusion provided to protrude inward in a radial direction. The elastic holding member includes a support bottom portion in contact with a transmitting-and-receiving-device bottom, an engagement recess provided to be recessed inward in the radial direction and thus house the engagement protrusion, and a leading projection provided at a position corresponding to the engagement recess with respect to a peripheral direction surrounding a central axis line, and provided to protrude from the support bottom portion toward the base-end side in the axial direction. The support bottom portion is formed as a thick portion. The engagement recess is provided in the support bottom portion.

Abstract: An object detector includes: an acquiring unit that acquires an oscillation signal corresponding to an oscillation of a microphone, the microphone transmitting a transmission wave, which is an ultrasonic wave, on a basis of a driving signal, and being caused to oscillate by a reflected wave generated as a result of the transmission wave being reflected from an object; a fall identifying unit that identifies a fall time point of a first drop from a value more than a threshold to the threshold or less after termination of the driving signal; a rise estimating unit that estimates a rise-in-reverberation time point of the reflected wave, the rise-in-reverberation time point being before the fall time point and after a time point of start of the driving signal; and a distance determining unit that determines a distance to the object on a basis of the rise-in-reverberation time point.