JP6429751B2 - Obstacle detection device - Google Patents

Description

  The present invention relates to an obstacle detection device that includes an ultrasonic sensor and detects an obstacle.

  Conventionally, in-vehicle ultrasonic sensors transmit and receive ultrasonic waves from the vibration plate toward the periphery of the vehicle by vibrating a vibration plate made of a member that does not transmit light, such as aluminum, with a ceramic vibrator or the like. The obstacle detection device detects an obstacle around the vehicle based on the transmission / reception result of the ultrasonic wave emitted by the ultrasonic sensor and reflected by the obstacle. When the obstacle detection device detects an obstacle around the vehicle using the ultrasonic sensor, the obstacle detection device, for example, outputs a buzzer sound from a speaker in the passenger compartment or blinks a warning light to alert the driver. Prompt.

  For example, in the vehicle obstacle detection device described in Patent Document 1, a transmission / reception unit and an LED (Light Emitting Diode) are housed in a bezel for attaching an ultrasonic sensor to a bumper. The bezel is formed of a light-transmitting member, and radiates light emitted from an LED provided inside the vehicle through a portion provided around a light-impermeable transmitting / receiving unit that is an aluminum diaphragm. By emitting light emitted from the LED when an obstacle is detected from the bezel around the aluminum diaphragm to the outside of the vehicle, it can be notified that the vehicle is approaching the outside of the vehicle.

JP 2005-178536 A

  Conventionally, the area of the bezel exposed on the bumper surface has been reduced so that the ultrasonic sensor installed on the bumper surface is not noticeable. For this reason, there is a problem in that the area of the light emitting portion is narrow and the light is not conspicuous when viewed from the outside of the vehicle, simply by adopting a configuration in which the light from the LED is transmitted through the bezel as in Patent Document 1.

  The present invention has been made to solve the above-described problems. By radiating light to the outside of the vehicle, the presence of the own vehicle is clearly indicated to pedestrians outside the vehicle and passengers in the surrounding vehicles. The purpose is to increase the visibility of the ultrasonic sensor to be invoked.

The obstacle detection device according to the present invention includes a vibration plate that transmits and receives ultrasonic waves in the air, a vibrator that vibrates the vibration board, and a vibration of the vibrator that is transmitted to the vibration plate. A transmission member that is installed on the back side of the diaphragm, emits light that is transmitted through the diaphragm and radiated to the front side, a transmission / reception control unit that controls the vibrator to transmit and receive ultrasonic waves, An obstacle detection unit that detects an obstacle using a transmission / reception result, and a light emission control unit that emits a light source unit when transmitting an ultrasonic wave from the diaphragm and when the obstacle detection unit detects an obstacle It is.

  According to the present invention, by using a light transmission type diaphragm, an area for emitting light is increased as compared with the case where a light non-transmission type diaphragm and a light transmission type bezel are used. be able to. Therefore, the light emitted from the ultrasonic sensor can be conspicuous, and the visibility of the ultrasonic sensor can be increased.

It is sectional drawing which shows the structural example of the ultrasonic sensor which concerns on Embodiment 1 of this invention. 6 is a cross-sectional view showing a modification of the ultrasonic sensor according to Embodiment 1. FIG. It is a block diagram which shows the structural example of the ultrasonic sensor which concerns on Embodiment 1, and the obstruction detection apparatus provided with the ultrasonic sensor. 2 is a diagram illustrating an example of a hardware configuration of an obstacle detection device according to Embodiment 1. FIG. 6 is a diagram illustrating an example of a vibrator according to Embodiment 1. FIG. 6 is a diagram illustrating a modification of the diaphragm in the ultrasonic sensor according to Embodiment 1. FIG. It is sectional drawing which shows the structural example of the ultrasonic sensor which concerns on Embodiment 2 of this invention, and is an example in which the surface of the diaphragm is convex. It is sectional drawing which shows the structural example of the ultrasonic sensor which concerns on Embodiment 2, and is an example in which the surface of the diaphragm is concave. It is a top view which shows the shape of a diaphragm and a holding member among the ultrasonic sensors which concern on Embodiment 3 of this invention. It is a figure which shows the structural example of the ultrasonic sensor which concerns on Embodiment 4 of this invention. FIG. 10 is a diagram illustrating a modification of the transmission member in the ultrasonic sensor according to the fourth embodiment. FIG. 10 is a diagram illustrating a modification of the ultrasonic sensor according to the fourth embodiment.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing a configuration example of an ultrasonic sensor 10 according to Embodiment 1 of the present invention. The ultrasonic sensor 10 includes a vibration plate 11 that transmits and receives ultrasonic waves, a holding member 12 that holds the vibration plate 11 so as to vibrate, a vibrator 13 that vibrates the vibration plate 11, and a vibration. A transmission member 14 that transmits vibration of the child 13 to the diaphragm 11, a light source unit 15 that is installed on the back side of the diaphragm 11 and emits light that passes through the diaphragm 11 and is emitted to the front side, and a case 16. ing.

  The case 16 is formed using, for example, a member that does not transmit light. The case 16 is attached to the bumper 1 of the vehicle, for example. The method for attaching the case 16 to the bumper 1 may be any method such as adhesion, screwing, or claw fitting.

The holding member 12 is formed using a member having flexibility and waterproofness. The holding member 12 holds the diaphragm 11 at the opening of the case 16 so as to vibrate. The diaphragm 11 is exposed from the hole of the bumper 1 to the outside of the vehicle with the case 16 attached to the bumper 1. Further, the vibrator 13, the transmission member 14, and the light source unit 15 are installed inside the case 16.
Here, a surface of the diaphragm 11 facing the outside of the vehicle is a front surface, and a surface of the diaphragm 11 facing the inside of the vehicle, that is, the case 16 side is a back surface.

  The vibrator 13 is an actuator that generates a driving force that vibrates the diaphragm 11 in the front-back direction. The vibrator 13 generates a driving force that vibrates the diaphragm 11 such as a piezoelectric actuator using a piezoelectric element, an electric actuator using electromagnetic force, or an electrostatic actuator using electrostatic attraction. Anything can be used. In FIG. 1, a multilayer piezoelectric element is schematically illustrated as the vibrator 13.

  The transmission member 14 has one end joined to the vibrator 13 and the other end joined to the back surface of the diaphragm 11, and can vibrate the surface of the diaphragm 11 by receiving the vibration of the vibrator 13. The vibrator 13 vibrates the diaphragm 11 by vibrating the transmission member 14 and transmits (radiates) ultrasonic waves toward the outside of the vehicle. The ultrasonic wave reflected by the obstacle 2 is received by the diaphragm 11, converted into an electric signal by the vibrator 13, and output.

  The diaphragm 11 is formed using a member such as a resin that transmits light. The diaphragm 11 in the first embodiment has rigidity, and the entire diaphragm 11 vibrates in the front and back direction. At least one light source unit 15 such as an LED is disposed on the back side of the diaphragm 11. The light emitted from the light source unit 15 passes through the diaphragm 11 and is emitted to the outside of the vehicle. Since light can be emitted from the entire surface of the diaphragm 11, the light emission area is larger than that in the case of using a conventional aluminum light-impermeable diaphragm and a light-transmissive bezel. Can be increased. In addition, the radiation efficiency can be increased. Therefore, the light emitted from the ultrasonic sensor 10 can be made conspicuous.

In addition, it is desirable that not only the diaphragm 11 but also the transmission member 14 be formed using a member that transmits light so as not to block light incident on the diaphragm 11 from the light source unit 15.
Further, the diaphragm 11 and the transmission member 14 may be integrally formed by injection molding of a resin material. Of course, the diaphragm 11 and the transmission member 14 may be separately formed and then joined and integrated. Examples of the resin material that transmits light include polycarbonate resin, acrylic resin, and styrene resin. Since the resin material has high strength and is lightweight, the area of the diaphragm 11 can be increased. Thereby, the sensitivity of the ultrasonic sensor 10 is improved. In addition, light emission can be conspicuous.

  FIG. 2 is a sectional view showing a modification of the ultrasonic sensor 10 according to the first embodiment. In the example of FIG. 2, a prism 17 serving as a light guide member is installed inside the case 16. The light emitted from the light source unit 15 is guided to the diaphragm 11 by the prism 17 and is transmitted through the diaphragm 11 and radiated to the outside of the vehicle.

Next, the obstacle detection apparatus 20 using the ultrasonic sensor 10 will be described.
FIG. 3 is a block diagram illustrating a configuration example of the obstacle detection apparatus 20 using the ultrasonic sensor 10 according to the first embodiment. The obstacle detection device 20 includes an ultrasonic sensor 10, a transmission / reception control unit 21, an obstacle detection unit 22, and a light emission control unit 23.

The transmission / reception control unit 21 outputs an instruction to transmit an ultrasonic wave to the transducer 13 of the ultrasonic sensor 10. In addition, when the transmission / reception control unit 21 instructs the transducer 13 to transmit ultrasonic waves, the transmission / reception control unit 21 outputs a notification notifying the transmission of ultrasonic waves to the light emission control unit 23. The vibrator 13 vibrates the diaphragm 11 via the transmission member 14 according to an instruction from the transmission / reception control unit 21 and transmits ultrasonic waves to the outside of the vehicle. Thereafter, the vibrator 13 receives the ultrasonic wave reflected by the obstacle 2 by the diaphragm 11, converts it into an electric signal, and outputs it to the transmission / reception control unit 21.
The transmission / reception control unit 21 receives the electrical signal from the transducer 13 and measures the time taken from transmission to reception of the ultrasonic wave. Then, the transmission / reception control unit 21 calculates the distance from the diaphragm 11 to the obstacle 2 using the measured time, and outputs the distance to the obstacle detection unit 22.

  The obstacle detection unit 22 receives the distance calculation result from the transmission / reception control unit 21. The obstacle detection unit 22 detects that the obstacle 2 is present around the vehicle when the distance is equal to or less than a predetermined distance. Then, the obstacle detection unit 22 outputs a notification notifying that the obstacle 2 has been detected to the light emission control unit 23.

  The light emission control unit 23 outputs a light emission instruction to the light source unit 15 of the ultrasonic sensor 10 when receiving a notification notifying transmission of ultrasonic waves from the transmission / reception control unit 21. Further, when the light emission control unit 23 receives a notification notifying that the obstacle 2 has been detected from the obstacle detection unit 22, the light emission control unit 23 outputs a light emission instruction to the light source unit 15 of the ultrasonic sensor 10. The light source unit 15 emits light according to an instruction from the light emission control unit 23. The light emitted from the light source unit 15 passes through the diaphragm 11 and is emitted to the outside of the vehicle.

By emitting light to the outside of the vehicle when the ultrasonic sensor 10 transmits ultrasonic waves, it is possible to notify a pedestrian or the like around the vehicle that an obstacle detection operation is being performed.
Further, when the obstacle detection device 20 detects the obstacle 2, the ultrasonic sensor 10 emits light to the outside of the vehicle, so that the vehicle approaches the pedestrian detected as the obstacle 2. Can be notified.
In that case, by making light emission conspicuous by radiating light from the entire surface of the diaphragm 11, it is possible to more reliably notify a pedestrian or the like.

  Although illustration is omitted, the obstacle detection device 20 outputs a buzzer sound from a speaker in the vehicle interior or blinks a warning light in the vehicle interior when the obstacle detection unit 22 detects the obstacle 2. Thus, the driver may be alerted. Since both the driver and the pedestrian share the detection of the obstacle 2, the occurrence of a contact accident or the like can be suppressed.

  When a plurality of ultrasonic sensors 10 are installed on the surface of the bumper 1, the obstacle detection device 20 can also control transmission / reception of ultrasonic waves and light emission for each of the plurality of ultrasonic sensors 10. . In the case of this configuration, the obstacle detection device 20 may control so that only the ultrasonic sensor 10 that detects the obstacle 2 emits light, or when the obstacle 2 is detected by any of the ultrasonic sensors 10. Not only the ultrasonic sensor 10 but also other ultrasonic sensors 10 may be controlled to emit light in conjunction with each other.

  Further, a plurality of light source units 15 having different emission colors may be provided, and the light source unit 15 that emits light may be arbitrarily selected depending on the situation. For example, the obstacle detection device 20 causes the green light source unit 15 to emit light when transmitting an ultrasonic wave, and causes the yellow light source unit 15 to emit light when the obstacle 2 is detected.

Next, a hardware configuration example of the obstacle detection device 20 will be described.
FIG. 4 is a diagram illustrating a hardware configuration example of the obstacle detection device 20 according to the first embodiment. Each function of the transmission / reception control unit 21, the obstacle detection unit 22, and the light emission control unit 23 in the obstacle detection device 20 is realized by a processing circuit. That is, the obstacle detection device 20 controls transmission / reception of ultrasonic waves from the diaphragm 11 by the vibrator 13, detects the obstacle 2 using the ultrasonic transmission / reception results, and transmits ultrasonic waves from the vibration plate 11. And a processing circuit for causing the light source unit 15 to emit light when the obstacle 2 is detected. The processing circuit is a processor 31 that executes a program stored in the memory 32.

  Each function of the transmission / reception control unit 21, the obstacle detection unit 22, and the light emission control unit 23 is realized by software, firmware, or a combination of software and firmware. Software or firmware is described as a program and stored in the memory 32. The processor 31 reads out and executes a program stored in the memory 32, thereby realizing the functions of the respective units. That is, the obstacle detection device 20 detects the obstacle 2 using the step of controlling transmission / reception of ultrasonic waves from the diaphragm 11 by the vibrator 13 and the ultrasonic transmission / reception results when executed by the processor 31. A memory 32 is provided for storing a program that results in the step of causing the light source unit 15 to emit light when transmitting ultrasonic waves from the diaphragm 11 and detecting the obstacle 2. In addition, this program can be said to cause a computer to execute the procedures or methods of the transmission / reception control unit 21, the obstacle detection unit 22, and the light emission control unit 23.

The processor 31 is also referred to as a CPU (Central Processing Unit), a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor).
The memory 32 may be, for example, a nonvolatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable ROM), or an EEPROM (Electrically EPROM). However, it may be a magnetic disk such as a hard disk or a flexible disk.

FIG. 5 shows an example of the vibrator 13. The vibrator 13 in FIG. 5 is a piezoelectric actuator, and includes a multilayer piezoelectric element 13a in which piezoelectric elements having positive and negative electrodes are stacked, a power source 13b, and a reception amplifier 13c. A transmission member 14 is joined to the multilayer piezoelectric element 13a. When receiving an instruction to transmit an ultrasonic wave from the transmission / reception control unit 21, the vibrator 13 applies a voltage to the multilayer piezoelectric element 13a, and expands and contracts the multilayer piezoelectric element 13a in the stacking direction. The diaphragm 11 vibrates via the transmission member 14 due to the expansion and contraction motion. When the diaphragm 11 is vibrated by the ultrasonic waves reflected by the obstacle 2, the vibration is transmitted to the multilayer piezoelectric element 13 a via the transmission member 14. The multilayer piezoelectric element 13a converts vibration into electric power and outputs an electric signal. The reception amplifier 13 c amplifies this electric signal and outputs it to the transmission / reception control unit 21.
In the above, a configuration using a multilayer piezoelectric element is shown, but a single-layer piezoelectric element may be used as long as sufficient characteristics are obtained.

  As described above, the ultrasonic sensor 10 according to Embodiment 1 includes the vibration plate 11 that transmits and receives ultrasonic waves in the air, the vibrator 13 that vibrates the vibration plate 11, and the vibration. The configuration includes a transmission member 14 that transmits vibration of the child 13 to the diaphragm 11 and a light source unit 15 that is installed on the back side of the diaphragm 11 and emits light that passes through the diaphragm 11 and is emitted to the front side. With this configuration, it is possible to increase the light emitting area as compared with a conventional case where a light non-transmissive diaphragm and a light transmissive bezel are used. Therefore, the light emitted from the ultrasonic sensor 10 can be made conspicuous, and the visibility of the ultrasonic sensor 10 can be increased.

  The obstacle detection apparatus 20 according to the first embodiment includes the ultrasonic sensor 10 described above, a transmission / reception control unit 21 that controls the vibrator 13 to transmit / receive ultrasonic waves, and an obstacle using the ultrasonic transmission / reception results. The obstacle detection unit 22 that detects the object 2 and the light emission control unit 23 that causes the light source unit 15 to emit light when transmitting ultrasonic waves from the diaphragm 11 and when the obstacle detection unit 22 detects the obstacle 2 are provided. It is a configuration. With this configuration, it is possible to notify a pedestrian around the vehicle, a passenger in the surrounding vehicle, and the like that the obstacle detection operation is being performed. Further, it is possible to notify the pedestrian detected as the obstacle 2 and the passengers of the surrounding vehicles that the vehicle is approaching.

The diaphragm 11 may have a function of scattering light.
For example, the diaphragm 11 is formed using a translucent member such as milky white resin. Thereby, the light emitted from the diaphragm 11 becomes scattered light. Further, for example, fine irregularities are formed on the surface of the vibration plate 11 to form a ground glass. Also in this case, the light emitted from the diaphragm 11 becomes scattered light.

  Since the diaphragm 11 has a light scattering function, light can be emitted in a wide range. Therefore, the light radiated to the outside of the vehicle on the surface of the bumper 1 can be made more conspicuous. Further, since the entire surface of the diaphragm 11 has a light scattering function, the entire surface of the diaphragm 11 emits light uniformly, so that unevenness of light is reduced and design as illumination is improved.

Further, the diaphragm 11 may have diffusion or condensing optical characteristics. FIG. 6 shows a modification of the diaphragm 11.
FIG. 6A is a plan view of the diaphragm 11, and FIG. 6B is a side view of the diaphragm 11. Four transparent convex lenses 11 a are formed on one surface of the vibration plate 11. The convex lens 11a has an optical characteristic that diffuses light radiated to the outside of the vehicle.
Although not shown, four light source portions 15 are arranged at four locations facing the four convex lenses 11a. With this configuration, since light is emitted from each of the four convex lenses 11a, light can be emitted in units of light sources.

Although illustration is omitted, the diaphragm 11 may have diffusion or condensing optical characteristics by forming an arbitrary polyhedral shape such as a concave lens or a brilliant cut, a prism or an emboss.
In addition, when noise is generated in the ultrasonic waves by applying shape processing for giving optical characteristics to the surface of the diaphragm 11, it may be performed on the back surface of the diaphragm 11.

  Since the diaphragm 11 has the optical characteristic of diffusion, light can be emitted in a wide range. Further, since the diaphragm 11 has a condensing optical characteristic, light can be emitted far away. Therefore, the range and direction in which light is emitted can be arbitrarily set.

Further, the light may be emitted from the diaphragm 11 in a plurality of directions outside the vehicle.
For example, the plurality of light source units 15 are installed in different directions in which light is emitted. Thereby, light can be radiated in a plurality of directions, and the light emission of the diaphragm 11 can be made more conspicuous. Alternatively, the four convex lenses 11a shown in FIG. 6 may be formed so that the optical axes of the convex lenses 11a are in different directions. By forming unevenness that refracts light on the surface of the diaphragm 11, light can be emitted in a plurality of directions, and light emission of the diaphragm 11 can be made more conspicuous.

Further, when the ultrasonic sensor 10 includes a plurality of light source units 15 and can emit light in a plurality of directions outside the vehicle, the light is selectively emitted in the direction in which the obstacle 2 is detected. Also good.
In that case, the obstacle detection unit 22 in the obstacle detection device 20 calculates the direction in which the obstacle 2 exists using the ultrasonic transmission / reception result. Since the method for calculating the direction of the obstacle 2 may be a known technique, a description thereof will be omitted. Then, the obstacle detection unit 22 outputs a notification notifying that the obstacle 2 has been detected and the direction in which the obstacle 2 has been detected to the light emission control unit 23. When the light emission control unit 23 receives the notification from the obstacle detection unit 22, the light emission control unit 23 controls to emit light from the light source unit 15 that emits light in the direction in which the obstacle 2 is detected among the plurality of light source units 15. .
With such a configuration, it is possible to notify the approach of the vehicle by emitting light toward a pedestrian or the like detected as the obstacle 2.

Embodiment 2. FIG.
In the first embodiment, the configuration example in which the surface of the diaphragm 11 is planar is shown. However, in the second embodiment, the configuration example in which the surface of the diaphragm 11 is convex or concave is shown.

FIG. 7 is a cross-sectional view illustrating a configuration example of the ultrasonic sensor 10 according to Embodiment 2, and the surface of the diaphragm 11 is a convex surface 11b.
FIG. 8 is a cross-sectional view illustrating a configuration example of the ultrasonic sensor 10 according to the second embodiment, and the surface of the diaphragm 11 is a concave surface 11c.
7 and 8, the same or corresponding parts as those in FIGS. 1 to 6 are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 7, when the surface of the diaphragm 11 is a convex surface 11b, the light emitted from the convex surface 11b converges and the ultrasonic wave transmitted from the convex surface 11b diffuses.
As shown in FIG. 8, when the surface of the diaphragm 11 is a concave surface 11c, the light emitted from the concave surface 11c diffuses, and the ultrasonic waves transmitted from the concave surface 11c converge.
7 and 8, the entire surface of the diaphragm 11 is the convex surface 11b or the concave surface 11c, but a part of the surface of the diaphragm 11 may be the convex surface 11b or the concave surface 11c.

  As described above, according to the second embodiment, the diffusion and convergence of the radiation light and the ultrasonic wave can be selected depending on whether the surface of the diaphragm 11 is the convex surface 11b or the concave surface 11c. For example, when the surface of the diaphragm 11 is the convex surface 11b and the ultrasonic wave is transmitted in a wide range, the number of ultrasonic sensors 10 installed in the vehicle can be reduced. Further, for example, when the surface of the diaphragm 11 is the concave surface 11c and the ultrasonic wave is transmitted far, an obstacle at a position away from the vehicle can be detected.

  As in the first embodiment, also in the second embodiment, the diaphragm 11 is made of a semi-transparent member, or fine irregularities are formed on the convex surface 11b and the concave surface 11c to form a ground glass. A light scattering function may be provided.

Embodiment 3 FIG.
In the second embodiment, the configuration example in which the diaphragm 11 has the convex surface 11b or the concave surface 11c to provide directivity has been described. However, in the third embodiment, the directivity is improved by changing the aspect ratio of the diaphragm 11. An example of the configuration is shown.

FIG. 9 is a plan view showing the shapes of the diaphragm 11 and the holding member 12 in the ultrasonic sensor 10 according to the third embodiment. 9, parts that are the same as or correspond to those in FIGS. 1 to 8 are given the same reference numerals, and descriptions thereof are omitted.
9A and 9B, the vertical direction corresponds to the vertical direction when the ultrasonic sensor 10 is installed on the bumper 1 of the vehicle, and the horizontal direction corresponds to the horizontal direction. Shall.

The substantial sliding surface of the diaphragm 11 shown in FIG. 9A is a rectangular shape that is long in the vertical direction and short in the horizontal direction. Moreover, the substantial rocking surface of the diaphragm 11 shown in FIG. 9B has an elliptical shape that is long in the vertical direction and short in the horizontal direction. With these configurations, the ultrasonic waves transmitted from the diaphragm 11 are narrow in the vertical direction and wide in the horizontal direction.
Although illustration is omitted, when the substantial peristaltic surface of the diaphragm 11 is vertically long and horizontally long, the ultrasonic waves transmitted from the diaphragm 11 are directed in the vertical direction and narrow in the horizontal direction. Have sex.

  As described above, according to the third embodiment, the directivity of the ultrasonic waves can be arbitrarily changed by making the peristaltic surface of the diaphragm 11 into shapes having different vertical and horizontal lengths. Therefore, the obstacle detection range can be optimized.

Embodiment 4 FIG.
In the first to third embodiments, a configuration example using a rigid member as the diaphragm 11 is shown. In the fourth embodiment, a configuration example using a flexible member as the diaphragm 11 is shown. .

FIG. 10 is a diagram illustrating a configuration example of the ultrasonic sensor 10 according to the fourth embodiment. 10A is a plan view of the ultrasonic sensor 10 viewed from the surface of the bumper 1, FIG. 10B is a cross-sectional view of the ultrasonic sensor 10 cut along the line AA ′, and FIG. 10C. FIG. 3 is a cross-sectional view of the ultrasonic sensor 10 cut along the line BB ′. In FIG. 10, the same or corresponding parts as those in FIGS. 1 to 9 are denoted by the same reference numerals and description thereof is omitted.
10A and 10B, the vertical direction corresponds to the vertical direction when the ultrasonic sensor 10 is installed on the bumper 1 of the vehicle, and the horizontal direction corresponds to the horizontal direction. Shall.

  In the fourth embodiment, the diaphragm 11 is formed using a flexible member. The outer edge of the diaphragm 11 is fixed to the opening of the case 16. That is, the outer edge portion of the diaphragm 11 functions as a holding member 12 that holds the diaphragm 11 so as to vibrate.

  Moreover, since the diaphragm 11 in Embodiment 4 has flexibility, the part mainly joined to the transmission member 14 in the diaphragm 11 bends and vibrates. Also in this configuration, similarly to the first to third embodiments, the vibrator 13 vibrates the diaphragm 11 by vibrating the transmission member 14 and transmits ultrasonic waves toward the outside of the vehicle. The ultrasonic wave reflected by the obstacle 2 is received by the diaphragm 11, and the vibrator 13 converts it into an electric signal and outputs it.

  Further, since the portion of the diaphragm 11 that is mainly joined to the transmission member 14 vibrates, the directivity of the ultrasonic wave is determined by the shape of the joint portion between the diaphragm 11 and the transmission member 14. Therefore, for example, as shown in FIG. 10, when the end surface of the transmission member 14 joined to the diaphragm 11 is formed into a rectangular shape that is long and short horizontally, the ultrasonic wave transmitted from the diaphragm 11 is narrow in the vertical direction. Wide directivity in the horizontal direction.

  On the other hand, the end face joined to the vibrator 13 of the transmission member 14 may have any shape. In the example of FIG. 10, the transmission member 14 has a shape that tapers toward the end face side to be joined to the vibrator 13, thereby reducing the weight of the transmission member 14. Since the transmission member 14 is light in weight, the vibration of the vibrator 13 is transmitted to the diaphragm 11 without being attenuated, so that the vibration amplitude of the diaphragm 11 is increased. Therefore, the sensitivity of the ultrasonic sensor 10 is improved.

Here, FIG. 11 shows a modification of the end face shape of the transmission member 14 joined to the diaphragm 11. FIG. 11A to FIG. 11C are views of the ultrasonic sensor 10 as viewed from the surface of the bumper 1.
In the example of FIG. 11A, the end surface joined to the diaphragm 11 of the transmission member 14 has an elliptical shape that is long in the vertical direction and short in the horizontal direction. Moreover, you may reduce in weight by making the transmission member 14 into a hollow cylinder shape, performing appropriate meat removal, or using the foaming material of the grade by which rigidity is maintained.
In the example of FIG. 11B and FIG. 11C, the end surface of the transmission member 14 joined to the diaphragm 11 has a cross shape that is long in the vertical direction and short in the horizontal direction.
In the case of the configuration shown in FIGS. 11A to 11C, the ultrasonic waves transmitted from the diaphragm 11 are narrow in the vertical direction and wide in the horizontal direction. Note that the shape of the end face of the transmission member 14 is not limited to the examples of FIGS. 10 and 11, and may be a shape corresponding to the directivity required for the ultrasonic sensor 10.

FIG. 12 shows a modification of the diaphragm 11. 12A is a view of the ultrasonic sensor 10 viewed from the surface of the bumper 1, FIG. 12B is a cross-sectional view of the ultrasonic sensor 10 cut along the line AA ′, and FIG. It is sectional drawing which cut | disconnected the ultrasonic sensor 10 along the BB 'line.
In the example of FIG. 12, an annular thin portion 11 d is formed at the boundary between the vibrating portion of the diaphragm 11 and the portion that functions as the holding member 12. By forming the thin portion 11d, the diaphragm 11 is easily bent and the amplitude of vibration is increased. Therefore, the sensitivity of the ultrasonic sensor 10 is improved. In addition, the shape of the thin part 11d is not limited to the example of FIG. 12, What is necessary is just the shape which makes the diaphragm 11 bend easily.

  As described above, according to the fourth embodiment, it is possible to arbitrarily change the directivity of the ultrasonic wave by making the joint surface between the diaphragm 11 and the transmission member 14 have different vertical and horizontal lengths. it can. Therefore, the obstacle detection range can be optimized.

  In the present invention, within the scope of the invention, any combination of each embodiment, any component of each embodiment can be modified, or any component of each embodiment can be omitted.

  DESCRIPTION OF SYMBOLS 1 Bumper, 2 Obstacle, 10 Ultrasonic sensor, 11 Diaphragm, 11a Convex lens, 11b Convex surface, 11c Concave surface, 11d Thin part, 12 Holding member, 13 Vibrator, 13a Multi-layer piezoelectric element, 13b Power supply, 13c Receiving amplifier, 14 transmission member, 15 light source unit, 16 case, 17 prism, 20 obstacle detection device, 21 transmission / reception control unit, 22 obstacle detection unit, 23 light emission control unit, 31 processor, 32 memory.

Claims (11)

A diaphragm that transmits and receives ultrasonic waves in the air, made of a member that transmits light;
A vibrator for vibrating the diaphragm;
A transmission member for transmitting vibration of the vibrator to the diaphragm;
A light source unit that is installed on the back side of the diaphragm and emits light that is transmitted to the front side through the diaphragm;
A transmission / reception control unit for controlling the vibrator to transmit / receive ultrasonic waves;
An obstacle detection unit that detects an obstacle using an ultrasonic transmission / reception result; and
An obstacle detection device comprising: a light emission control unit that causes the light source unit to emit light when transmitting ultrasonic waves from the diaphragm and when the obstacle detection unit detects an obstacle. A plurality of the light source units having different emission colors;
The light emission control unit, by controlling the light emission of the plurality of the light source unit of different emission colors, according to claim 1, wherein the controlling the color of light emitted to the front side by passing through the diaphragm Obstacle detection device. The light emission control unit, when the obstacle detecting unit detects an obstacle, the obstacle detection apparatus according to claim 1, wherein the controlling the emission direction of light in a direction of detecting the obstacle. The obstacle detection device according to claim 1, wherein the diaphragm is a transparent or translucent member . 2. The obstacle detection device according to claim 1, wherein unevenness for scattering or refracting light is formed on a surface of the diaphragm . The diaphragm, obstacle detection device according to any one of claims 1, 4 or 5, characterized in that the surface is concave or convex. The obstacle detection device according to any one of claims 1, 4, 5, and 6 , wherein the vibration surface of the diaphragm has different vertical and horizontal lengths . The obstacle detection device according to any one of claims 1, 4, 5, 6 and 7 , wherein a joining surface between the diaphragm and the transmission member has different lengths in the vertical and horizontal directions. . The obstacle detection device according to claim 1 , wherein the diaphragm is a resin material . The obstacle detection device according to any one of claims 1, 4, 5, 6, 7, 8, and 9 , further comprising a plurality of the light source units that emit light in different directions . The obstacle detection according to any one of claims 1, 4, 5, 6, 7, 8, 9 and 10 , wherein the vibrator is of a piezoelectric type, an electric type or an electrostatic type. apparatus.

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