Ultrasonic sensor

Abstract

A cover member of an ultrasonic sensor has a first engagement portion and a second engagement portion, which are respectively engaged with a third engagement portion and a fourth engagement portion of a sensor body. The engagement portions are arranged in such a manner that a force applied to the cover member due to an engagement between the first engagement portion and the third engagement portion and a force applied to the cover member due to an engagement between the second engagement portion and the fourth engagement portion respectively have opposite directions to be substantially countervailed when the sensor body is attached to the cover member. Thus, the cover member can be restricted from slanting when the sensor body is fixed to the cover member.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings, in which:

FIG. 1 is a partially sectional side view showing an ultrasonic sensor which is attached to a bumper according to a preferred embodiment of the present disclosure;

FIG. 2A is a front view showing the ultrasonic sensor according to the preferred embodiment, FIG. 2B is a right side view showing the ultrasonic sensor, FIG. 2C is a plan view showing the ultrasonic sensor, and FIG. 2D is a rear view showing the ultrasonic sensor;

FIG. 3 is a cross-sectional view taken along a line III-III in FIG. 2A;

FIG. 4 is a cross-sectional view showing an ultrasonic transducer according to the preferred embodiment;

FIG. 5A is a front view showing a cover member according to the preferred embodiment, FIG. 5B is a left side view showing the cover member, FIG. 5C is a rear view showing the cover member, FIG. 5D is a plan view showing the cover member, and FIG. 5E is a bottom view showing the cover member;

FIG. 6 is a partially enlarged sectional view taken along a line VI-VI in FIG. 5C;

FIG. 7 is a schematic view showing the ultrasonic sensor before attachment to the bumper according to the preferred embodiment;

FIG. 8 is a partially sectional view showing a state of a midstream of the attachment of the ultrasonic sensor to the bumper according to the preferred embodiment;

FIG. 9 is a partially sectional side view showing the cover member when being inserted into a hole portion of the bumper according to the preferred embodiment;

FIG. 10 is a partially enlarged sectional view showing a state when the ultrasonic transducer and an opening portion of a sensor body are inserted into a hollow portion of the cover member according to the preferred embodiment;

FIG. 11 is a partially sectional side view showing a state when the opening portion of the sensor body has been inserted into the hollow portion of the cover member according to the preferred embodiment;

FIG. 12 is a partially sectional view showing a fixing construction of an ultrasonic sensor to a bumper according to a prior art; and

FIG. 13 is a schematic view showing attachment of an ultrasonic sensor according to a comparison example proposed by the inventors of the present invention.

Claims

1. An ultrasonic sensor, comprising: a cover member having a hollow portion which defines therein a space and has an opening at one end thereof; anda sensor body having an ultrasonic transducer, an insertion part of the sensor body which includes the ultrasonic transducer being inserted in the hollow portion from the opening of the cover member, wherein:the insertion part of the sensor body is inserted in the hollow portion of the cover member from one side of a base after the cover member is inserted through a hole portion of the base from an other side of the base, so that the sensor body is attached to the base through the cover member,the one side and the other side of the base being opposite to each other;the cover member has a first engagement portion and a second engagement portion which are positioned to be opposite to each other with respect to the hollow portion of the cover member;the sensor body has a third engagement portion which is engaged with the first engagement portion, and a fourth engagement portion which is engaged with the second engagement portion; andthe first engagement portion, the second engagement portion, the third engagement portion and the fourth engagement portion are arranged, in such a manner that a force applied to the cover member due to an engagement between the first engagement portion and the third engagement portion has a direction opposite to that of a force applied to the cover member due to an engagement between the second engagement portion and the fourth engagement portion when the sensor body is attached to the cover member.

2. The ultrasonic sensor according to claim 1, wherein: the first engagement portion is a snap fit, which protrudes from an outer surface of the hollow portion of the cover member and has a nail portion protruding from a tip thereof;the third engagement portion is a receiving portion which is arranged at the sensor body and has a substantial frame shape to construct a hole in which the nail portion is fitted; andwhen the sensor body is attached to the cover member, the nail portion is pressed against an inner wall of the receiving portion so that a force facing a substantial axial direction of the hollow portion of the cover member is applied to the snap fit.

3. The ultrasonic sensor according to claim 2, wherein the snap fit has a slit which surrounds the nail portion.

4. The ultrasonic sensor according to claim 3, wherein: the slit surrounds two opposite sides of the nail portion, and a rear side of the nail portion with respect to an insertion direction of the tip of the snap fit into the hole of the receiving portion; andwhen the tip of the snap fit is inserted into the hole of the receiving portion, the nail portion is elastically deformed in such a manner that a part of the nail portion of a front side in the insertion direction constructs a fulcrum and a tip of the nail portion constructs an exertion point.

5. The ultrasonic sensor according to claim 1, wherein: the second engagement portion is a hole portion which is arranged at the hollow portion of the cover member;the fourth engagement portion is a lance which protrudes from the sensor body and has a nail portion fitted in the hole portion; andwhen the sensor body is attached to the cover member, the hollow portion of the cover member is pressed by the nail portion so that the a force facing a substantial axial direction of the hollow portion is applied to the cover member.

6. The ultrasonic sensor according to claim 1, wherein the base is a vehicle component.