Ultrasonic sensor assembly
An ultrasonic sensor assembly includes an ultrasonic sensor apparatus, a holding member and a spring arrangement. The spring arrangement includes two spring portions, which are connected together by a connecting portion. The spring portions are partially secured to a housing of the ultrasonic sensor apparatus and are resiliently deformed between the housing and a rear surface of a bumper. The spring portions and a flange portion of the holding member cooperate together to clamp the bumper therebetween.
1. An ultrasonic sensor assembly that is installable to a through hole of an installation object, which extends from a first surface to a second surface of the installation object, the ultrasonic sensor assembly comprising:
an ultrasonic sensor apparatus that includes a sensor arrangement and a housing, wherein the sensor arrangement is held by the housing and is received in the through hole of the installation object upon installation of the ultrasonic sensor assembly to the installation object;
a holding member that holds the ultrasonic sensor apparatus relative to the installation object, wherein the holding member includes:
a flange portion, which is secured to the first surface of the installation object around a peripheral edge of the through hole of the installation object upon the installation of the holding member to the installation object;
a holding portion, which is connected to the flange portion and extends through the through hole of the installation object upon the installation of the holding member to the installation object, so that the holding portion projects from the second surface of the installation object; and
a plurality of spring portions, which are partially secured to the housing of the ultrasonic sensor apparatus and are resiliently deformed between the housing and the second surface of the installation object, wherein the spring portions and the flange portion cooperate together to clamp the installation object therebetween.
2. The ultrasonic sensor assembly according to claim 1 , wherein the plurality of spring portions includes two spring portions, which are connected to each other through a connecting portion to form a double torsion spring.
3. The ultrasonic sensor assembly according to claim 2 , wherein:
the housing of the ultrasonic sensor apparatus includes:
an engaging protrusion, to which a generally central point of the connecting portion is engaged; and
two positioning portions, which position a part of a first side section and a part of a second side section, respectively, of the connecting portion;
the first side section of the connecting portion is located between one of the two spring portions and the generally central point of the connecting portion;
the second side section of the connecting portion is located between the other one of the two spring portions and the generally central point of the connecting portion; and
the double torsion spring is detachably installed to the housing.
4. The ultrasonic sensor assembly according to claim 3 , wherein:
the two positioning portions are provided in one of two adjacent surfaces of the housing; and
the engaging protrusion is provided in the other one of the two adjacent surfaces of the housing.
5. The ultrasonic sensor assembly according to claim 1 , wherein:
the installation object is made of a metal material; and
each spring portion is engaged with the installation object through a dielectric material.
6. The ultrasonic sensor assembly according to claim 5 , wherein an engaging part of each spring portion, which is engaged with the installation object, is covered with the dielectric material.
7. The ultrasonic sensor assembly according to claim 5 , wherein the dielectric material is interposed between the spring portion and the installation object.
8. The ultrasonic sensor assembly according to claim 1 , wherein the installation object is a bumper of a vehicle.
9. The ultrasonic sensor assembly according to claim 1 , wherein each spring portion is spirally wound.