JP2012230002A - Ultrasonic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic sensor which can improve aesthetic appearance in a state that it is attached to a bumper.SOLUTION: An ultrasonic sensor comprises: a body block 3 which holds at least one of transmitting means for transmitting ultrasonic waves and receiving means for receiving ultrasonic waves; and a mounting base which is connected to the body block 3 and is fixed to the internal surface of a bumper 1. The body block 3 includes a cylindrical insertion part 41 which is inserted to a circular exposure hole 11 provided in the bumper 1 with its axis direction oriented to the direction of thickness of the bumper 1. The external peripheral surface of the insertion part 41 is provided with four contacting protrusions 46 having a common dimensional shape for being in contact with the internal peripheral surface of the exposure hole 11. Because the center of the insertion part 41 is more easily matched with the center of the exposure hole 11, seen from the external side of the bumper 1, than in a case that there are no contacting protrusions 46, the appearance can be improved.

Description

  The present invention relates to an ultrasonic sensor.

  Conventionally, an ultrasonic sensor that transmits ultrasonic waves and receives ultrasonic waves reflected by an obstacle has been provided. Examples of this type of ultrasonic sensor include a Doppler sensor that determines the presence or absence of an obstacle based on a Doppler shift in received ultrasonic waves.

  As the above-described ultrasonic sensor, there is one used by being fixed to a bumper so as to be inserted into an exposure hole provided in a bumper of an automobile. Said exposure hole is provided in the front side or rear side of a motor vehicle. Thereby, for example, an obstacle in the detection range 7 as shown in FIG. 7 is detected.

  Further, as the ultrasonic sensor, as shown in FIG. 8, an outer block 81 inserted into the exposure hole 11 from the outer surface side of the bumper 1, and an inner block 82 coupled to the outer block 81 from the inner surface side of the bumper 1 And the outer block 81 and the inner block 82 are fixed to the bumper 1 by being joined with the bumper 1 sandwiched therebetween (see, for example, Patent Document 1).

  However, in the structure in which the bumper 1 is sandwiched between the outer block 81 and the inner block 82 as described above, a part of the outer block 81 protrudes to the outer surface side (left side in FIG. 8) of the bumper 1, so that the bumper The appearance when attached to 1 was poor.

  Therefore, as shown in FIGS. 9 (a) and 9 (b), the present inventor has two body blocks 2 that are bonded and fixed to the inner surface of the bumper 1, and a main body block that holds transmission / reception means for transmitting and receiving ultrasonic waves. 3 is proposed. Each mounting base 2 and the main body block 3 have coupling portions 22 and 53 that are detachably coupled to each other by concavo-convex engagement. According to this ultrasonic sensor, since it is not necessary to project a part of the ultrasonic sensor to the outside of the bumper 1, the appearance can be improved.

JP 2010-194441 A

  Here, when the exposure hole has a circular shape and the portion (hereinafter referred to as “insertion portion”) 41 to be inserted into the exposure hole in the main body block 3 has a cylindrical shape, the center of the exposure hole 11 and the insertion portion 41 are formed. When it was off the center, it looked bad.

  The present invention has been made in view of the above reasons, and an object of the present invention is to provide an ultrasonic sensor capable of improving the appearance when attached to a bumper.

  An ultrasonic sensor according to the present invention is an ultrasonic sensor attached to a bumper, and includes a main body block including at least one of a transmission unit that transmits ultrasonic waves and a reception unit that receives ultrasonic waves, and is connected to the main body block And a mounting base fixed to the inner surface of the bumper, and the main body block has an insertion portion that is inserted into an exposed hole provided in the bumper so that an axial direction is directed in a thickness direction of the bumper. The outer peripheral surface of the insertion portion has a plurality of contact convex portions that have the same size and shape and abut against the inner peripheral surface of the exposure hole, and the contact convex portions exist around the central axis of the insertion portion. It is characterized in that it is arranged in such a way that the angle that does not become larger than 180 °.

  In this ultrasonic sensor, it is desirable that three or more contact convex portions are provided.

  Further, in this ultrasonic sensor, each of the contact convex portions has an inclined portion in which the projecting dimension from the insertion portion is gradually reduced toward the end in the direction of insertion into the exposure hole. Is desirable.

  In this ultrasonic sensor, it is preferable that a surface of the contact convex portion that contacts the inner peripheral surface of the exposure hole is a convex curved surface having a larger curvature than the inner peripheral surface of the exposure hole.

  Further, in this ultrasonic sensor, the main body block can be displaced in a direction perpendicular to the axial direction of the insertion portion with respect to the mounting base in a state where the mounting base and the main body block are connected to each other. It is desirable to have a structure.

  Further, in this ultrasonic sensor, the main body block includes a sensor main body having the insertion portion and the contact convex portion, and a coupling body connected to the sensor main body and the mounting base, respectively. It is desirable that the main body block and the connecting body are structured such that the connecting body can be displaced with respect to the sensor main body in a direction orthogonal to the axial direction of the insertion portion in a state where they are connected to each other.

  Furthermore, in the ultrasonic sensor, it is preferable that each of the contact convex portions is not extended to an end in a direction of being inserted into the exposure hole in the main body block.

  According to the present invention, it is possible to improve the appearance because the center of the insertion portion easily matches the center of the exposure hole when viewed from the outside of the bumper as compared with the case where the contact convex portion is not provided.

It is sectional drawing which shows the principal part of the state by which embodiment of this invention was attached to the bumper. It is the perspective view seen from the inner surface side of the bumper which shows the state attached to the bumper. It is a disassembled perspective view which shows the same as the above. It is a perspective view which shows a main body block same as the above. It is the perspective view seen from the outer surface side of the bumper which shows the state attached to the bumper. It is a perspective view which shows the principal part of a sensor main body same as the above. It is explanatory drawing which shows an example of the usage condition of an ultrasonic sensor. It is sectional drawing which shows the state by which the conventional ultrasonic sensor was attached to the bumper. (A) (b) is the perspective view seen from the inner surface side of a bumper which shows another prior art example, (a) shows the state by which the main body block was isolate | separated from each mounting base, (b) is a main body The state which the block couple | bonded with each mounting base is shown.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  As shown in FIG. 2, the present embodiment is fixed to a bumper 1 in which a circular exposure hole 11 is provided, and each inner surface of the bumper 1 (see FIG. 2, and two main bodies 3 that are detachably coupled to the respective mounting bases 2 by concavo-convex engagement.

  Hereinafter, the directions of ABCDEF in FIG. That is, of the thickness direction of the bumper 1, the direction on the inner surface side and the direction attached to the bumper 1 in this direction are referred to as “upward”, and the direction in which the mounting bases 2 are arranged is referred to as “left-right direction”. Note that the above directions are defined for convenience of explanation, and do not necessarily match the directions in the actual use state. In the present embodiment, the lower direction in the above expression is usually the front or the rear of the vehicle. Used towards.

  More specifically, each mounting base 2 is made of, for example, a synthetic resin, and each mounting base 2 has a common dimensional shape. As shown in FIG. 3, each of the mounting bases 2 has a rectangular flat plate-like fixing portion 21 whose thickness direction is the vertical direction and the longitudinal direction is the front-rear direction, and the front-rear direction on the upper surface of the fixing portion 21. And a flat plate-like coupling portion 22 projecting from the center portion and having the thickness direction directed in the front-rear direction. The lower surface of the fixing portion 21 of each mounting base 2 is bonded and fixed to the inner surface of the bumper 1 using, for example, a well-known adhesive sheet. In addition, as a method of fixing each mounting base 2 to the inner surface of the bumper 1, instead of the above-described adhesive fixing, other methods such as adhesive fixing using an adhesive, welding, and screwing are used. May be used.

  Further, an engaging convex portion 221 is projected on one surface (front surface in the figure) of the coupling portion 22 of the mounting base 2, and the engaging convex portion 221 is directed toward the upper end as a whole ( In other words, the protrusion is inclined so that the protruding dimension becomes smaller.

  The body block 3 includes a sensor body 4 and a connecting body 5 interposed between the sensor body 4 and the mount 2.

  The sensor body 4 includes a columnar insertion portion 41 whose axial direction is directed vertically, a body portion 42 connected to the upper end of the insertion portion 41, and a connector portion 43 protruding from the front surface of the body portion 42. Have. In addition, a cylindrical transmission / reception unit 45 that is coaxial with the insertion unit 41 and has a smaller outer diameter than the insertion unit 41 protrudes from the lower surface of the insertion unit 41 of the sensor body 4. The transmission / reception unit 45 holds transmission / reception means (not shown) that serves as both transmission means for transmitting ultrasonic waves and reception means for receiving ultrasonic waves. It is an incident / exit surface that emits light. Specifically, for example, the outer surface of the sensor body 4 other than the transmission / reception unit 45 is formed of a housing made of synthetic resin, and the transmission / reception unit 45 is made of a material harder than the housing (for example, aluminum) and is held by the housing. A part of another part protrudes out of the housing. Further, the transmission / reception means described above performs mutual conversion between ultrasonic waves and electric signals, and such transmission / reception means can be realized by a known technique using, for example, a piezoelectric element. The main body 42 accommodates circuit components constituting a signal processing circuit that performs signal processing such as amplification and noise removal between the transmission / reception means and the external circuit. The connector 43 constitutes a connector for electrical connection between the signal processing circuit and an external circuit. Since the above signal processing circuit and connector can be realized by a well-known technique, detailed illustration and description thereof are omitted.

  The connecting body 5 includes two engaging portions 51 that are connected to the sensor main body 4 by concavo-convex engagement so as to sandwich the sensor main body 4 from the left and right sides, and a connecting portion 52 that connects the engaging portions 51.

  Here, on the left and right side surfaces of the main body portion 42 of the sensor main body 4, engagement convex portions 44 are provided so as to project outward in the left-right direction. As shown in FIG. 4, each engagement portion 51 of the connecting body 5 has an engagement hole 511 penetrating left and right, and the engagement protrusion 44 is engaged with the engagement hole 511. Thus, the sensor body 4 and the connecting body 5 are connected to each other. Further, the size and shape of the engagement hole 511 is larger than the engagement convex portion 44 in each of the vertical direction and the front-rear direction, and in particular, the dimension in the front-rear direction (left-right direction in FIG. 4) is larger than the vertical direction. The difference in shape has been increased. Thereby, even when the sensor main body 4 and the connecting body 5 are coupled to each other, the connecting body 5 is somewhat in the front-rear direction, which is a direction orthogonal to the axial direction (vertical direction) of the insertion portion 41 with respect to the sensor main body 4. Is displaceable.

  In addition, in each engaging portion 51, two connecting portions 53 that are connected to the connecting portions 22 of the respective mounting bases 2 project outwardly in the left-right direction. Each coupling portion 53 of the connecting body 5 has two sandwich pieces 531 and 532 which are flat with the thickness direction being the front-rear direction and are opposed to each other with a gap therebetween. The coupling body 5 is made of a material that can be elastically deformed, for example, a synthetic resin, and each coupling portion 53 can be elastically deformed so as to increase the distance between the lower end portions of the sandwiching pieces 531 and 532. . Further, in each coupling portion 53 of the coupling body 5, an engagement hole 533 into which the engagement convex portion 221 of the mounting base 2 is engaged is provided in the front clip piece 531. Further, in order to easily generate the elastic deformation, an appropriate slit 534 is provided around the engagement hole 533 in the sandwiching piece 531 of each coupling portion 53.

  When the present embodiment is fixed to the bumper 1, first, the two mounting bases 2 are bonded and fixed to the inner surface of the bumper 1 so as to sandwich the exposure hole 11. At this time, the front surfaces of the coupling portions 22 are flush with each other between the two mounting bases 2, and the distance between the centers of the coupling convex portions 221 is matched with the distance between the centers of the engagement holes 533.

  Further, one connecting portion 22 of the mounting base 2 is introduced between the sandwiching pieces 531 and 532 of each connecting portion 53 of the main body block 3, and the main body block 3 is pushed downward (that is, the bumper 1 side). Then, as the sandwiching piece 531 slides on the inclined surface of the engaging convex part 221, each coupling part 53 is elastically deformed to increase the distance between the lower ends of the sandwiching pieces 531 and 532, respectively. Eventually, when the engagement holes 533 of the respective coupling portions 53 reach the engagement convex portions 221, the respective engagement convex portions 221 engage with the respective engagement holes 533 as the coupling portions 53 are elastically restored. Here, in the main body block 3 (connector 5), the upward displacement (that is, the direction away from the bumper 1) is limited by the contact between the inner surface of the engagement hole 533 and the engagement convex portion 221 of the mounting base 2, The connection of the main body block 3 (connection body 5) to each mounting base 2 and the attachment to the bumper 1 of this embodiment are completed. Further, rotation of the sensor body 3 around the axis of the insertion portion 41 is prohibited by contact between the clip pieces 531 and 532 and the coupling portion 22 of the mounting base 2. In the above state, the upper end portion of the clip piece 531 having the engagement hole 533 is positioned above the upper end of the coupling portion 22 of the mounting base 2.

  Actually, the work of bonding and fixing each mounting base 2 to the bumper 1 may be after the work of connecting each mounting base 2 to the connecting body 5.

  Here, in the state where the main body block 3 is attached to the mounting base 2 as described above, the projecting dimension of the main body block 3 (transmission / reception section 45) downward from the fixing portion 21 of the mounting base 2 is assumed to be attached. The thickness of the bumper 1 is substantially the same. Thereby, in a state where the mounting of the present embodiment to the bumper 1 is completed, the lower end surface of the main body block 3 (that is, the lower surface of the transmission / reception unit 45) is substantially flush with the outer surface (lower surface) of the bumper 1, as shown in FIG. Become one.

  Further, the dimension of the engagement hole 533 in the left-right direction is larger than the dimension of the engagement protrusion 221 in the left-right direction. Thereby, even when the main body block 3 and each mounting base 2 are connected to each other, the main body block 3 (connecting body 5) is in the left-right direction (the vertical direction that is the axial direction of the insertion portion 41) with respect to each mounting base 2. It can be displaced in the direction perpendicular to the axis.

  When the main body block 3 is removed from each mounting base 2, the portion above the coupling portion 22 of the mounting base 2 in the sandwiching piece 531 having the engagement hole 533 is rearward (that is, in a direction approaching the other sandwiching piece 532). Press. Then, the coupling portion 53 is elastically deformed so that the above-described sandwiching piece 531 rotates with the contact point with the coupling portion 22 of the mount 2 as a fulcrum, and the engagement between the engagement hole 533 and the engagement convex portion 221 is released. Therefore, the main body block 3 (connector 5) may be displaced upward (that is, in a direction away from the fixing portion 21 of the mounting base 2) as it is.

  Hereafter, the characteristic part of this embodiment is demonstrated.

  On the outer peripheral surface of the insertion portion 41, as shown in FIG. 6, four contact convex portions 46 each having a common size and shape are arranged at regular intervals about 90 ° around the axis of the insertion portion 41. 41 is projected outward in the radial direction. Each contact convex portion 46 has a shape that is vertically long, and the lower end of each contact convex portion 46 (that is, the end in the insertion direction of the insertion portion 41 into the exposure hole 11) is the lower end of the main body block 3 (that is, transmission / reception). It is located above the lower end of the portion 45.

  Further, except for the lower end portion of each contact convex portion 46, the outer diameter is a semi-cylindrical shape smaller than the inner diameter of the exposure hole 11. That is, the outer peripheral surface of each contact convex portion 46 is a convex curved surface having a larger curvature than the inner peripheral surface of the exposure hole 11.

  Furthermore, the lower end part of each contact convex part 46 is a semi-conical truncated cone shape that is continuous with the above-described semi-cylindrical shape, and an inclined part 461 that is inclined so as to reduce the protruding dimension from the insertion part 41 toward the lower end. It has become. When the insertion portion 41 is inserted into the exposure hole 11, the insertion portion 41 is guided to the center of the exposure hole 11 because the inclined portion 461 is in sliding contact with the inner peripheral surface of the exposure hole 11. Thereby, compared with the case where the inclination part 461 is not provided, insertion of the insertion part 41 to the exposure hole 11 becomes easy.

  As shown in FIG. 1, in a state where the attachment to the bumper 1 is completed, each contact convex portion 46 comes into contact with the inner peripheral surface of the exposure hole 11. Here, the projecting dimension of each contact convex portion 46 from the outer peripheral surface of the insertion portion 41 is preferably equal to the difference between the inner diameter of the exposure hole 11 and the outer diameter of the insertion portion 41, but the elasticity that can occur Depending on the degree of deformation or plastic deformation, the above protrusion dimension may be larger than the above difference.

  According to the above configuration, the appearance can be improved because the center of the insertion portion 41 easily matches the center of the exposure hole 11 when viewed from the outside of the bumper 1 as compared with the case where the contact convex portion 46 is not provided. . In addition, the number and arrangement | positioning of each contact convex part 46 are not restricted above. For example, even when the two contact convex portions 46 are arranged at an interval of 180 ° on the outer peripheral surface of the insertion portion 41 (that is, on the opposite sides across the central axis of the insertion portion 41), the above effect is obtained. It is believed that there is. However, in order to suppress rattling due to elastic deformation or plastic deformation of the contact protrusion 46, the contact protrusion 46 has an angle where the contact protrusion 46 does not exist around the central axis of the insertion portion 41 is less than 180 °. It is desirable to provide three or more in such an arrangement.

  Further, in the present embodiment, since the inclined portion 461 is provided at the lower end of each contact convex portion 46, it is difficult for the catch to occur when each contact convex portion 46 is introduced into the exposure hole 11. Accordingly, it is easier to introduce each contact convex portion 46 into the exposure hole 11 than when the inclined portion 461 is not provided.

  Furthermore, in the present embodiment, the surface that contacts the inner peripheral surface of the exposure hole 11 in the contact convex portion 46 is a convex curved surface that has a larger curvature than the inner peripheral surface of the exposure hole 11. Therefore, the contact area between the main body block 3 and the bumper 1 is smaller than the case where the curvatures of the contact convex portion 46 and the inner peripheral surface of the exposure hole 11 are equal to each other. Therefore, it is difficult for vibration that causes erroneous determination to be transmitted from the bumper 1 to the main body block 3.

  Further, in this embodiment, even when the connection of the main body block 3 to each mounting base 2 is completed, the main body block 3 (connecting body 5) is in the left-right direction with respect to each mounting base 2 (that is, the axial direction of the insertion portion 41). Can be displaced in a direction orthogonal to Furthermore, in this embodiment, the sensor body 4 can be displaced in the front-rear direction (that is, the direction orthogonal to the axial direction of the insertion portion 41) with respect to the connection body 5 even when the connection of the connection body 5 to the sensor body 4 is completed. It has become. Thus, for example, when the main body block 3 is mounted after the respective mounting bases 2 are fixed to the bumpers 1, even if there is an error in the fixing position of each mounting base 2, the error is detected by the main body block with respect to each mounting base 2. 3 and the displacement of the sensor body 4 with respect to the connector 5 can be absorbed. The connecting structure that allows the main body block 3 to be displaced with respect to the mounting base 2 and the connecting structure that enables the sensor main body 4 to be displaced with respect to the connecting body 5 can be appropriately changed. For example, the design margin may be appropriately increased so that the size of the concave portion is larger than the size of the convex portion among the portions engaging with each other.

  Furthermore, in this embodiment, the lower end of each contact convex portion 46 (that is, the end in the insertion direction of the insertion portion 41 into the exposure hole 11) is respectively lower than the lower end of the main body block 3 (that is, the lower end of the transmission / reception portion 45). Is also located above. Therefore, compared with the case where each contact convex part 46 is each extended to the lower end of the main body block 3, introduction of the main body block 3 (the transmission / reception part 45 and the insertion part 41) to the exposure hole 11 becomes easy, and the bumper 1 As seen from the outside, the contact protrusions 46 are less noticeable and the appearance is improved.

  The main body block 3 has a structure in which each coupling portion 53 is continuously formed as a part of the housing of the sensor main body 4 in place of the sensor main body 4 and the connecting body 5 as described above. Also good.

DESCRIPTION OF SYMBOLS 1 Bumper 2 Mounting stand 3 Main body block 4 Sensor main body 5 Connection body 11 Exposed hole 41 Insertion part 46 Contact convex part 461 Inclination part

Claims (7)

An ultrasonic sensor attached to a bumper,
A main body block comprising at least one of a transmitting means for transmitting ultrasonic waves and a receiving means for receiving ultrasonic waves;
A mounting base connected to the main body block and fixed to the inner surface of the bumper;
The main body block has an insertion portion that is inserted with an axial direction toward a thickness direction of the bumper with respect to an exposure hole provided in the bumper,
On the outer peripheral surface of the insertion portion, there are a plurality of contact convex portions that have a common size shape and abut against the inner peripheral surface of the exposure hole, and the contact convex portions do not exist around the central axis of the insertion portion An ultrasonic sensor characterized in that the angle is set so as not to be larger than 180 °.   The ultrasonic sensor according to claim 1, wherein three or more contact convex portions are provided.   Each of the contact convex portions has an inclined portion in which a projecting dimension from the insertion portion is gradually reduced toward an end in a direction in which the contact convex portion is inserted into the exposure hole. The ultrasonic sensor according to claim 2.   The surface contacting the inner peripheral surface of the exposure hole in the contact convex portion is a convex curved surface having a larger curvature than the inner peripheral surface of the exposure hole. The ultrasonic sensor according to item.   The mounting base and the main body block are connected to each other, and the main body block is configured to be displaceable in a direction perpendicular to the axial direction of the insertion portion with respect to the mounting base. The ultrasonic sensor according to any one of claims 1 to 4. The main body block comprises a sensor main body having the insertion portion and the contact convex portion, and a connecting body connected to the sensor main body and the mounting base, respectively.
The main body block and the connecting body are structured such that the connecting body is displaceable with respect to the sensor body in a direction orthogonal to the axial direction of the insertion portion in a state of being connected to each other. The ultrasonic sensor of any one of Claims 1-5.   The ultrasonic sensor according to claim 1, wherein each of the contact convex portions is not extended to an end in a direction of being inserted into the exposure hole in the main body block. .

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