JP2001337172A - Ultrasonic detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic detector capable of widening detection distance and detection scope, and improving the functions. SOLUTION: An ultrasonic sensor 10 has a vibrator 11 for which transmit and receives ultrasonic waves and formed into a substantially circular columnar shape, a buffer member 12 covering the side face part of the vibrator 11, and a housing 14 arranged around the buffer member 12 and storing the buffer member 12. The ultrasonic sensor 10 forms a space A around a front side of the vibrator 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic detector installed on a bumper of an automobile and detecting an obstacle.

[0002]

2. Description of the Related Art Conventionally, some bumpers and the like of automobiles are equipped with a corner sensor provided with an ultrasonic sensor for detecting an obstacle and an ultrasonic detector called a back sonar. 9 to 11 are drawings showing a conventional ultrasonic detector. FIG. 9 is a front view, FIG. 10 is a plan view, and FIG. 11 is a sectional view taken along line HH of FIG.

[0003] In FIGS. 9 to 11, reference numeral 1 denotes a vibrator of an ultrasonic sensor, which is covered with a cushioning material 2 and a sheet 3. The periphery of the vibrator 1 is fitted to the housing 4 via the cushioning material 2. The back surface of the vibrator 1 is electrically connected to a substrate 6 via a lead wire 5. A control circuit 7 and a harness 8 are provided on the board 6. On the back side of the housing 4, a back cover 9 is arranged and closed.

FIG. 12 is a vibration characteristic diagram showing a detectable range of the vibrator 1 when the cushioning member 2, the sheet 3, and the housing 4 are not provided around the vibrator 1. The vibration characteristic diagram shown in FIG. 12 represents the original detectable range of the vibrator 1 itself. The distance at which an object can be detected is 90 [cm] in the left-right direction and 86 [cm] in the up-down direction. It is. In this case, since the vibrator 1 is not held down by covering the periphery with the cushioning material 2 or the sheet 3, the vibrator 1 vibrates freely and emits an ultrasonic wave, so that the detectable range is wide.

[0005]

However, the vibrator 1 of the above-described ultrasonic detector usually covers the front periphery of the vibrator 1 with a cushioning material 2 as shown in FIGS. It is installed inside. Transducer 1 of the ultrasonic detector
When the front periphery of the vibrator 1 is covered with a cushioning material 2 and fixed, as shown in the vibration characteristic diagram of FIG. Since free vibration is suppressed by the housing 4, it deteriorates to 80 [cm] in the horizontal direction and 70 [cm] in the vertical direction. In particular, when the sensor is downsized and the vibrator is fixed by covering the periphery of the vibrator with a thin-walled housing 4, in particular, the vibration characteristics are greatly deteriorated, and the original detection range characteristics (FIG. 12) of the ultrasonic vibrator 1 can be obtained. There is a problem that there is no.

For this reason, the conventional ultrasonic detector uses the vibrator 1
In order to maintain the original detection distance and detection range capability of the vibrator 1 lost by fixing the cushioning material 2, the sheet 3, and the housing 4 around the ultrasonic detector, the entire ultrasonic detector is required. Must be larger. However, when the size of the ultrasonic detector is increased, a large hole is formed in the bumper to install the ultrasonic detector. Therefore, there is a problem that the strength of the bumper is reduced and the appearance is deteriorated.

[0007] Further, even if the conventional ultrasonic detector increases the size of the entire ultrasonic detector and expands the range in which an object can be detected, the detection capability increases not only in the horizontal direction but also in the vertical direction. There is a problem that the road surface is erroneously detected as an object.

The present invention increases the detection distance and the detection range,
An object of the present invention is to provide an ultrasonic detector with improved functions.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the prior art, and a first aspect of the present invention is a vibrator having a substantially cylindrical shape which receives and transmits ultrasonic waves. And a cushioning material that covers the side surface of the vibrator, and a housing that is disposed around the cushioning material and houses the cushioning material, wherein the ultrasonic sensor includes a front side of the vibrator. A space A is formed around it.

According to a second aspect of the present invention, in the first aspect, the space A is formed by an annular groove formed between an opening end of the front housing and the vibrator.

According to a third aspect of the present invention, in the second aspect of the present invention, the surface of the vibrator and the opening end of the housing are arranged flush with each other, and the surface of the cushioning material is provided on the vibrator. It is arranged at a position recessed from the front surface and the open end of the housing.

The invention according to claim 4 is the invention according to claim 2 or 3.
In the invention described above, the annular groove includes an arc-shaped groove formed in the vibrator, and a gap formed by a protrusion protruding from an inner opening end of the housing and an outer wall of the vibrator. .

[0013] The invention of claim 5 is the invention of claim 2 or 3.
In the invention described in the above, the annular groove includes an arc-shaped groove formed in a vertical direction of the vibrator, a projecting portion projecting from a surface of the cushioning material in the annular groove to right and left portions of an inner open end of the housing. And a gap formed by the outer wall of the vibrator.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3, reference numeral 10 denotes an ultrasonic sensor that is implanted in a bumper of an automobile and detects an obstacle or the like. The ultrasonic sensor 10 uses an ultrasonic wave called an obstacle detection sensor, a proximity sensor, a corner sensor, a back sensor, a vehicle height sensor, a road surface sensor, a human body detection sensor, or the like to detect an object or an object. It is used for various sensors that detect distance. When the ultrasonic sensors 10 are installed and used on a bumper of an automobile, six to eight ultrasonic sensors 10 are installed at the left and right central portions of each of the front and rear side bumpers of the vehicle body to detect obstacles, Detect the distance to.

Reference numeral 11 denotes a vibrator for transmitting and receiving ultrasonic waves, which has a cylindrical shape, and has a vibrating element for receiving and transmitting ultrasonic waves inside the surface side. As shown in FIG. 2, the vibrator 11 is fixed by covering the outer periphery with a substantially cylindrical cushioning material 12. On the back side of the vibrator 11, a back side opening 1 of the cushioning material 12 is provided.
The lead wire 15 is fixedly attached to the sheet 13 whose 2a is closed. The cushioning member 12 is made of, for example, a rubber material such as silicon rubber or a soft resin material.

A housing 14 made of resin is fitted around the cushioning material 12 covering the vibrator 11. The surface 11a of the vibrator 11 and the open end 1 of the housing 14
4a is arranged substantially flush as shown in FIG. still,
The surface 11a of the vibrator 11 may be slightly protruded from the open end 14a of the housing 14 or may be depressed.

In the ultrasonic sensor 10, the vibrator 11
Surface 1 of cushioning material 12 arranged between
2a is the surface 11a of the vibrator 11 and the housing 1
4 is located at a position recessed from the opening end 14a of the vibrator 11
A space A is formed by forming an annular groove 10a around the periphery.

The depth and width of the annular groove 10a and the cushioning material 1
The thickness of 2 is, for example, about 1 [mm] when the diameter of the vibrator 11 is 14 [mm].

The space A is provided with the vibrator 11 and the cushioning material 1.
By projecting from the opening end 14a of the housing 14 which is flush with the surface 12a of the
A space A may be formed on the side periphery. in this case,
Since the vibrator 11 has the space A in the peripheral portion on the surface 11a side, the members for suppressing the vibration of the vibrator 11 are eliminated by the space A, and the vibration of the vibrator 11 becomes smooth.
In this case, a detectable range very close to the characteristics of the vibrator 11 itself can be obtained.

A back surface of the vibrator 11 is electrically connected to a substrate 16 via a lead 15. A sheet 3 made of a soft material having a buffering property such as urethane on which the lead wires 15 in the housing 14 are arranged;
6 is filled with a filler C such as silicon. The cushioning material 12, the sheet 13, and the lead wire 15
Is more firmly fixed by the filler C. The housing 14 is implanted or fitted at the center of the front and rear bumpers and at the left and right sides of the vehicle.

The board 16 is provided with an electric component 17 such as an electronic element constituting a control circuit of the ultrasonic sensor 10 and a harness 18. On the back side of the housing 14, a back cover 19 is arranged and closed. A space D between the substrate 16 and the back cover 19 in the housing 14 is filled with a filler E such as silicon. The substrate 1
6, the electrical component 17, the back cover 19, and the connection portion between the harness 18 and the substrate 16 are more firmly fixed by the filler E. Incidentally, the lid member 19 may be integrated with the housing 14.

FIG. 3 shows an annular groove 10 formed by disposing the cushioning material 12 at a deep position around the vibrator 11.
FIG. 4 is a vibration characteristic diagram of a detection range of the ultrasonic sensor 10 having a. As shown in FIG. 3, by forming the annular groove 10 a, it is possible to reduce the suppression of the vibration of the vibrator 11, and the vibration of the vibrator 11 can be made smooth without resistance, and the detectable distance can be reduced. 12 is 110 cm in both the horizontal and vertical directions and the vertical direction as compared with the conventional one shown in FIGS.
Can be stretched.

The ultrasonic wave transmitted from the vibrator 11 returns to the element inside the vibrator 11 after a part of the ultrasonic wave that has returned upon hitting the object enters the annular groove 10 a adjacent to the front periphery of the vibrator 11. , The detectable distance can be extended beyond the function of the vibrator 11 itself.

Second Embodiment Hereinafter, a second embodiment of the present invention will be described in detail with reference to FIGS. In the second embodiment of the present invention, the annular groove 10 of the ultrasonic sensor 10 of the first embodiment described above is used.
a is an annular groove 20a shaped as shown in FIG. Hereinafter, the same components as those of the above-described first embodiment will be denoted by the same reference numerals, and description thereof will be omitted.

4 to 6, reference numeral 20 denotes an ultrasonic sensor, and a cylindrical vibrator 21 for receiving and transmitting ultrasonic waves is disposed at the center of the front surface side. The vibrator 21 has a substantially cylindrical cushioning material 22 fixed and covered on the outer periphery. The vibrator 21
Is a sheet 13 made of a soft resin such as urethane on the back side.
And the lead wire 15 are fixed. The sheet 13 covers the back surface side opening 22 b of the cushioning material 22 and covers the back surface of the vibrator 21.

A housing 24 is fitted around the cushioning material 22 covering the vibrator 21. The surface 21a of the vibrator 21 and the open end 24a of the housing 24
As shown in FIG. 5, they are arranged substantially flush. In the ultrasonic sensor 20, the surface 22a of the cushioning member 22 disposed between the vibrator 21 and the housing 24 is located at a position recessed from the surface 21a of the vibrator 21 and the open end 24a of the housing 24. A space F is formed by forming an annular groove 20 a around the periphery of the groove 21.

As shown in FIG. 4, the annular groove 20a has substantially arc-shaped protrusions 24b and 24c protruding from the left and right sides of the open end 24a of the housing 24 toward the center P of the vibrator 21.
Is formed, the upper and lower portions are formed into wide and symmetrical arc-shaped grooves 20b and 20c, and the left and right portions are formed into narrow arc-shaped gaps 20d and 20e.

FIG. 6 shows an annular groove 20 formed by arranging the cushioning material 22 in a recessed position around the vibrator 21.
FIG. 6 is a vibration characteristic diagram of the detection range of the ultrasonic sensor 20 according to the second embodiment shown in FIGS. 4 and 5 having a. In the present embodiment, the annular groove 20a is formed on the front side surface of the vibrator 21, and the protrusions 24b, 2 are formed on the left and right of the annular groove 20a.
4c.

As a result, the suppression of the vibration of the vibrator 21 by the buffer material 22 can be reduced, and the vibrator 2
1 is made smooth without resistance, and compared with the vibration characteristics of the detection range of the conventional ultrasonic sensor shown in FIGS. 12 and 13 described above, the protruding portions 24b and 24c give directivity to the detection range. As shown in FIG. 6, the detectable distance can be increased to 96 [cm] in the horizontal direction and the vertical direction.

The ultrasonic sensor 20 includes projections 24b, 24
By appropriately changing the shape and size of c as needed, changing the directivity and extending the detection distance,
It is possible to provide an ultrasonic detector suitable for a place to be installed. For example, in the ultrasonic sensor 20 installed on the bumper behind the vehicle body, the detection range in the vertical direction is narrowed, and the distance for detecting the object is increased without detecting the road surface.
It is possible to detect the presence of the object early when the vehicle body is backed, and to prevent the vehicle body from colliding with the object.

When the ultrasonic sensors 20 are installed on the bumpers at the front left and right ends of the vehicle body, it is possible to detect an object over a wide range from the side to the front of the vehicle body. Further, the ultrasonic sensor 20 changes the directivity so that, for example, each ultrasonic sensor 2 is located within the object detection range of all three ultrasonic sensors installed at the center, left, and right of the bumper.
It is possible to eliminate the unevenness of the space in which no object can be detected without overlapping the range of the object detected by 0.

Third Embodiment Hereinafter, a third embodiment of the present invention will be described in detail with reference to FIGS. 7 and 8. In the third embodiment of the present invention, the protrusions 24b and 24c formed on the housing 24 of the second embodiment described above are replaced with the protrusions 27a formed on the cushioning material 27 as shown in FIGS. , 27b. Hereinafter, the same components as those of the above-described second embodiment will be denoted by the same reference numerals, and description thereof will be omitted.

In FIGS. 7 and 8, reference numeral 25 denotes an ultrasonic sensor, and a cylindrical vibrator 26 for receiving and transmitting ultrasonic waves is disposed at the center of the front surface side. The vibrator 26 has a substantially cylindrical cushioning material 27 fixed and covered on the outer periphery. The vibrator 26
Is a sheet 13 made of a soft resin such as urethane on the back side.
And the lead wire 15 are fixed. The sheet 13 covers the back side opening 27c of the cushioning material 27 and covers the back side of the vibrator 26.

A housing 28 is fitted around the cushioning material 27 covering the vibrator 26. A surface 26a of the vibrator 26, an open end 28a of the housing 28,
The surfaces 27d of the protruding portions 27a, 27b are arranged substantially flush as shown in FIG. In the ultrasonic sensor 25,
The surface 27d of the cushioning member 27 disposed between the vibrator 26 and the housing 28 forms an annular groove 25a located at a position recessed from the surface 26a of the vibrator 26 and the open end 28a of the housing 28 to form a space G And has protruding portions 27a and 27b that bisect the space G.

The annular groove 25a, as shown in FIG.
It is formed adjacent to the vibrator 26. The annular groove 2
5a is a substantially arc-shaped protrusion 27 protruding from the bottom surface of the annular groove 25a toward the left and right around the front side of the vibrator 26.
The annular groove 25a is divided into two parts by filling the annular groove 25a with a and 27b. The annular groove 25a is formed of wide and symmetrical arcuate grooves 25b and 25c at two upper and lower locations, and narrow arcuate gaps 25d and 25e at two right and left locations.
Consists of

An annular groove 25a formed by arranging the cushioning material 27 in a recessed position around the vibrator 26, and a superstructure in which the annular groove 25a is divided into two parts by protrusions 27a and 27b of the cushioning material 27. In the vibration characteristic diagram of the detection range of the acoustic wave sensor 25, substantially the same data as the data of the second embodiment described above is obtained.

As a result, the suppression of the vibration of the vibrator 26 by the buffer material 27 can be reduced.
6 is smoothed without resistance, and compared with the vibration characteristics of the detection range of the conventional ultrasonic sensor shown in FIGS. 12 and 13 described above, as in the second embodiment, the protrusion 2
The detection range can be given directivity by 7a and 27b, and the same operation and effect as in the second embodiment can be obtained.

[0038]

The present invention has the following configuration and operation, and has the following effects. The invention according to claim 1 includes a vibrator that receives and transmits ultrasonic waves and has a substantially cylindrical shape, a cushioning material that covers a side surface of the vibrator, and a housing that is arranged around the cushioning material and houses the cushioning material. In the ultrasonic sensor, the ultrasonic sensor has a configuration in which the space A is formed around the front side of the vibrator, so that even if a cushioning material or a housing is provided around the ultrasonic vibrator, The function can be exhibited without reducing the inherent detection capability range. The ultrasonic sensor according to the first aspect has a wider detectable range than the conventional ultrasonic sensor in which the entire side surface of the vibrator is covered with the cushioning material, and can improve the performance without increasing the number of parts.

According to a second aspect of the present invention, in the first aspect, the space A has an annular groove formed between the opening end of the housing on the front side and the vibrator. Without increasing the number of parts, the detection capability range of the ultrasonic detector can be expanded with a simple structure, and the performance can be improved. Further, since the performance of the ultrasonic detector can be improved, the size of the ultrasonic detector can be reduced compared to other ultrasonic detectors having the same function, and the material cost of the housing can be reduced. By reducing the size of the ultrasonic detector, it is possible to improve the appearance of the installation location of the bumper and the like, and also to reduce the ultrasonic detector hole of the bumper where the ultrasonic detector is installed to improve the strength of the bumper. it can.

According to a third aspect of the present invention, in the second aspect of the present invention, the surface of the vibrator and the opening end of the housing are flush with each other, and the surface of the cushioning material is provided on the vibrator. By arranging it at a position recessed from the front surface and the opening end of the housing, it is possible to reduce the amount of the buffer material corresponding to the space volume, thereby reducing the material cost. Also,
By arranging the surface of the vibrator and the opening end of the housing flush, it is possible to prevent the ultrasonic detector installed on the surface of the bumper or the like from hitting an object and being damaged.

The invention according to claim 4 is the invention according to claim 2 or 3.
In the invention described in the above, the annular groove is constituted by an arc-shaped groove formed in the vibrator, and a gap formed by a protrusion protruding from an inner opening end of the housing and an outer wall of the vibrator. In addition, the detection range of the ultrasonic detector can have directivity in the horizontal direction and the vertical direction, and the detectable range and distance can be improved. In addition, the ultrasonic sensor can be provided with a desired directivity to the vibrator by appropriately changing the shape and size of the protruding portion as necessary, and can be used to extend the detection distance and install the ultrasonic sensor. An ultrasonic detector suitable for a location can be obtained. Also, the ultrasonic sensor changes the directivity by reducing the detectable angle range in the vertical direction that can detect the object,
It is possible to prevent the road surface from being erroneously detected as an object. Further, since the protruding portion is disposed in front of the cushioning material, it is possible to prevent the cushioning material from falling off the ultrasonic sensor.

The invention of claim 5 is the invention of claim 2 or 3.
In the invention described in the above, the annular groove includes an arc-shaped groove formed in a vertical direction of the vibrator, a projecting portion projecting from a surface of the cushioning material in the annular groove to right and left portions of an inner open end of the housing. The gap formed between the vibrator and the outer wall has the same effect as that of the fourth aspect, and the vibrator and the cushioning material can be inserted and assembled from the front side of the housing. The child and the cushioning material can be easily assembled to the housing.

[Brief description of the drawings]

FIG. 1 is a drawing showing a first embodiment of the present invention, and is a front view of an ultrasonic sensor.

FIG. 2 is a sectional view taken along line II of FIG. 1;

FIG. 3 is a graph showing the first embodiment of the present invention, and is a pie chart showing an obstruction detectable range of the ultrasonic sensor.

FIG. 4 is a drawing showing a second embodiment of the present invention, and is a front view of an ultrasonic sensor.

FIG. 5 is a sectional view taken along line JJ of FIG. 4;

FIG. 6 is a graph showing the second embodiment of the present invention, and is a pie chart showing an obstacle detectable range of the ultrasonic sensor.

FIG. 7 is a drawing showing a third embodiment of the present invention, and is a front view of an ultrasonic sensor.

FIG. 8 is a sectional view taken along line KK in FIG. 7;

FIG. 9 is a front view of a conventional ultrasonic sensor.

FIG. 10 is a plan view of a conventional ultrasonic sensor.

FIG. 11 is a sectional view taken along line HH of FIG. 9;

FIG. 12 is a pie chart showing an obstacle detectable range of an ultrasonic sensor having no conventional cushioning material and housing.

FIG. 13 is a pie chart showing an obstacle detectable range of a conventional ultrasonic sensor.

[Explanation of symbols]

 10, 20, 25 Ultrasonic sensor 10a, 20a, 25a Annular groove 11, 21, 26 Transducer 11a, 21a, 26a Surface 12, 22, 27 Buffer material 12a, 22a, 27d Surface 14, 24, 28 Housing 14a, 24a , 28a Open ends 20b, 20c, 25b, 25c Arc-shaped grooves 20d, 20e, 25d, 20e Gap 24b, 24c, 27a, 27b Projection A, F, G space

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04R 1/28 330 H04R 1/28 330 1/32 330 1/32 330

Claims (5)

[Claims] A vibrator (11, 21, 26) which receives and transmits ultrasonic waves and has a substantially cylindrical shape, and a cushioning material (12, 22, 27) for covering a side surface of the vibrator (11, 21, 26). ) And the cushioning material (12, 22, 2)
7) and housings (14, 24, 28) arranged around the cushioning material (12, 22, 27), wherein the ultrasonic sensors (10, 20, 25) are provided. , 20, 25) surround the front surfaces of the transducers (11, 21, 26) with spaces (A, F,
An ultrasonic detector, wherein G) is formed. 2. The invention according to claim 1, wherein said space (A, F, G) is provided on a front housing (1).
4, 24, 28) open end (14a, 24a, 25a)
And an annular groove (10a, 20a, 25a) formed between the vibrator and the vibrator (12, 22, 26). 3. The invention according to claim 2, wherein the surfaces (11a, 21) of the vibrators (11, 21, 26) are provided.
a, 26a) and the housing (14, 24, 28)
And the opening ends (14a, 24a, 28a) of the cushioning material (12, 22, 27) are arranged flush with each other.
a, 27a) and the surface (11a, 21a, 26a) of the vibrator (11, 21, 26) and the housing (1).
4, 24, 28) open end (14a, 24a, 28a)
An ultrasonic detector characterized by being placed in a position that is recessed from a wall. 4. The invention according to claim 2, wherein the annular groove (20a) is formed between an arc-shaped groove (20b, 20c) formed in the vibrator (11) and the housing (24). Projecting portions (24b, 24c) projecting from the inner opening end (24a) and the vibrator (21)
(20d, 20e) formed with the outer wall of the ultrasonic detector. 5. The invention according to claim 2, wherein the annular groove (25a) is formed in an arc-shaped groove (25b, 25c) formed in a vertical direction of the vibrator (26). The surface (2) of the cushioning material (27) in (25a)
7a) to the inside open end (28a) of the housing (28)
A gap (25d, 2) formed between the protruding portions (27a, 27b) protruding to the left and right portions and the outer wall of the transducer (26).
5e). An ultrasonic detector, comprising: