WO2005020631A1 - 音響整合体およびその製造方法、ならびに超音波センサおよび超音波送受信装置 - Google Patents
音響整合体およびその製造方法、ならびに超音波センサおよび超音波送受信装置 Download PDFInfo
- Publication number
- WO2005020631A1 WO2005020631A1 PCT/JP2004/011900 JP2004011900W WO2005020631A1 WO 2005020631 A1 WO2005020631 A1 WO 2005020631A1 JP 2004011900 W JP2004011900 W JP 2004011900W WO 2005020631 A1 WO2005020631 A1 WO 2005020631A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- porous
- acoustic matching
- ceramic
- porous body
- gel
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 45
- 230000008569 process Effects 0.000 title description 9
- 239000000919 ceramic Substances 0.000 claims abstract description 224
- 239000002002 slurry Substances 0.000 claims abstract description 36
- 239000000843 powder Substances 0.000 claims abstract description 30
- 238000000465 moulding Methods 0.000 claims abstract description 25
- 238000001035 drying Methods 0.000 claims abstract description 17
- 238000005245 sintering Methods 0.000 claims abstract description 10
- 239000010410 layer Substances 0.000 claims description 87
- 239000011159 matrix material Substances 0.000 claims description 56
- 238000004519 manufacturing process Methods 0.000 claims description 54
- 239000002245 particle Substances 0.000 claims description 53
- 239000011148 porous material Substances 0.000 claims description 50
- 239000002344 surface layer Substances 0.000 claims description 50
- 238000010304 firing Methods 0.000 claims description 25
- 229910052809 inorganic oxide Inorganic materials 0.000 claims description 21
- 238000009826 distribution Methods 0.000 claims description 15
- 230000005540 biological transmission Effects 0.000 claims description 14
- 229920005989 resin Polymers 0.000 claims description 14
- 239000011347 resin Substances 0.000 claims description 14
- 239000002184 metal Substances 0.000 claims description 11
- 229910052751 metal Inorganic materials 0.000 claims description 11
- 239000007858 starting material Substances 0.000 claims description 11
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 230000002093 peripheral effect Effects 0.000 claims description 3
- 239000002131 composite material Substances 0.000 abstract description 34
- 230000000994 depressogenic effect Effects 0.000 abstract 2
- 239000006260 foam Substances 0.000 abstract 1
- 239000000499 gel Substances 0.000 description 56
- 239000007789 gas Substances 0.000 description 32
- 239000000243 solution Substances 0.000 description 21
- 239000000463 material Substances 0.000 description 11
- 238000004891 communication Methods 0.000 description 10
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 10
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 9
- 238000010586 diagram Methods 0.000 description 9
- 239000011521 glass Substances 0.000 description 9
- 229910010271 silicon carbide Inorganic materials 0.000 description 9
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 8
- 230000008859 change Effects 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 238000005259 measurement Methods 0.000 description 8
- 238000005520 cutting process Methods 0.000 description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 6
- 239000000853 adhesive Substances 0.000 description 6
- 230000001070 adhesive effect Effects 0.000 description 6
- 239000004005 microsphere Substances 0.000 description 6
- 238000005498 polishing Methods 0.000 description 6
- 239000011800 void material Substances 0.000 description 6
- 238000005238 degreasing Methods 0.000 description 5
- 238000001879 gelation Methods 0.000 description 5
- 238000001000 micrograph Methods 0.000 description 5
- 239000011268 mixed slurry Substances 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000004809 Teflon Substances 0.000 description 4
- 229920006362 Teflon® Polymers 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000005187 foaming Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 230000001965 increasing effect Effects 0.000 description 4
- 239000011259 mixed solution Substances 0.000 description 4
- 230000001902 propagating effect Effects 0.000 description 4
- 239000000377 silicon dioxide Substances 0.000 description 4
- 125000006850 spacer group Chemical group 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 3
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000002708 enhancing effect Effects 0.000 description 3
- 229920006332 epoxy adhesive Polymers 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000035515 penetration Effects 0.000 description 3
- 229910000077 silane Inorganic materials 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910052582 BN Inorganic materials 0.000 description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000003321 amplification Effects 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 239000004088 foaming agent Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000000644 propagated effect Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 239000004094 surface-active agent Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002734 clay mineral Substances 0.000 description 1
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 238000004049 embossing Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- -1 for example Substances 0.000 description 1
- 239000003349 gelling agent Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000003915 liquefied petroleum gas Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 229910052575 non-oxide ceramic Inorganic materials 0.000 description 1
- 239000011225 non-oxide ceramic Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229910052574 oxide ceramic Inorganic materials 0.000 description 1
- 239000011224 oxide ceramic Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/80—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using ultrasonic, sonic or infrasonic waves
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R17/00—Piezoelectric transducers; Electrostrictive transducers
Definitions
- the present invention particularly includes a ceramic porous body for efficiently transmitting ultrasonic waves generated by vibrating means into a gas or efficiently receiving ultrasonic waves propagating in a gas.
- the present invention relates to an acoustic matching body, an ultrasonic sensor using the same, and an ultrasonic transmitting and receiving apparatus that performs transmission and reception signal processing of an ultrasonic wave using the ultrasonic sensor.
- an acoustic matching layer used for an ultrasonic sensor is formed of a porous body (for example,
- Patent Document 1 JP-A-6-327098 (Patent Document 1)).
- the ultrasonic sensor 101 includes a piezoelectric body sandwiched between a pair of opposed electrodes 106.
- the acoustic matching layer 103 is, for example, a material in which minute hollow spheres are uniformly dispersed in an epoxy resin, and has a sound speed of 1800 m / s and a density of 0.7 ⁇ 10 3 kg / m 3 .
- porous bodies used for the acoustic matching layer.
- a typical example is a thin layer of a mixture of ceramic powder and acrylic microspheres, which is thinly applied on a film, dried, and then peeled off from the film. It is produced by sintering ceramics in an electric furnace at an elevated temperature until the ceramic powders are combined. A void is formed by burning off the acrylic microspheres, and a porous body is formed.
- the characteristics of the porous body manufactured in this way are that the voids are minute and that the voids have a uniform distribution (see Japanese Patent Application Laid-Open No. 2002-51398 (Patent Document 2)). .
- acoustic matching member there is a member having a configuration in which a plurality of small pieces are assembled and joined to each other at contact surfaces of the small pieces (for example, Japanese Patent Application Laid-Open No. 2001-346295). See Patent Document 3)). Further, a method of manufacturing an acoustic matching layer using an acoustic matching layer material in which hollow spheres are mixed in a resin is disclosed (Japanese Patent Application Laid-Open No. 2002-58099 (Patent Document 4)).
- JP-A-2-177799 Patent Document 5
- a structure is obtained in which the hollow spheres form a matrix and are connected to each other at the contact points of the matrices of the adjacent hollow spheres, but have voids between the hollow spheres.
- Japanese Patent Application Laid-Open No. 2-177799 describes that this structure has a sound velocity of about 900 m / s and an acoustic impedance of about 4.5 ⁇ 10 5 kg / m 2 s. Since the acoustic impedance is defined as the product of density) and sound velocity (C) ⁇ ⁇ ), the matrix of this hollow sphere is calculated to have a density of about 0.5 g / cm 3 .
- an acoustic matching layer made of a dried gel of an inorganic oxide is also known (see, for example, JP-A-2002-262394 (Patent Document 6)). This is also a porous structure and has pores having dimensions on the order of nanometers.
- Such a dried gel of an inorganic oxide is obtained with a density of 0.5 g / cm 3 or less and a sound velocity of 500 m / s or less.
- the acoustic matching layer of this composite structure has a first layer and a second layer, and the acoustic impedance Z1 of the first layer and the acoustic impedance Z2 of the second layer satisfy the relationship of Z1> Z2.
- the two layers consist of a dry gel force of an inorganic oxide.
- the first layer of the acoustic matching layer having the composite structure includes acrylic microspheres, SiO powder, and gas.
- the porous body is manufactured by polishing it to an appropriate size, for example, a diameter of 12 mm and a thickness of 0.85 mm.
- the application describes that it is useful to configure the acoustic matching layer with a plurality of members having different acoustic impedances, particularly, different members. Further, in order to realize this, the first acoustic matching layer (porous body) is gelled and dried. It is described that an inorganic oxide material having fluidity before filling is filled and then solidified to form the second acoustic matching layer.
- a physical shape effect anchor effect
- Patent Document 1 JP-A-6-327098
- Patent Document 2 JP 2002-51398 A
- Patent Document 3 Japanese Patent Application Laid-Open No. 2001-346295
- Patent Document 4 JP-A-2002-58099
- Patent Document 5 Japanese Patent Application Laid-Open No. 2-177799
- Patent Document 6 JP-A-2002-262394
- Patent Document 7 Japanese Patent Application Laid-Open No. 2001-261463
- acoustic matching members have not always been satisfactory from at least one of their characteristics and ease of manufacture.
- the ultrasonic sensor using the same may be affected by the temperature characteristics of the resin, and the amplitude and cycle of the transmission / reception waveform of the ultrasonic wave may change depending on the temperature.
- Such a change due to temperature is not suitable for performing gas flow measurement with an ultrasonic receiver using an ultrasonic sensor.
- a dried gel of an inorganic oxide has excellent characteristics suitable for an acoustic matching member.
- An acoustic matching member having a composite structure in which this is used as the second layer and another porous body is used as the first layer also has excellent characteristics.
- the strength of the bond between the dried gel of the inorganic oxide and the porous body of the first layer may not be sufficient.
- the method of manufacturing the first layer specifically described in Japanese Patent Application No. 2003-140687 cannot always be easily implemented. For example, a powder mixture of acrylic microspheres, SiO powder, and glass frit
- the member obtained by the manufacturing method of removing and sintering the acrylic microspheres needs to be polished to an appropriate size after sintering. Strong polishing is necessary because the dimensional force of the member obtained after sintering shrinks to about one third of the size of the pressed powder before sintering, and warpage occurs in the member after sintering. It becomes.
- the work of polishing a member so that the main surface thereof has a predetermined area, and the degree of warpage and unevenness of the main surface is within a predetermined range is generally complicated and time-consuming.
- Dried gels of inorganic oxides are not practical because they have low strength and are easily chipped. This is because, for example, in an acoustic matching member in which the second layer, which is a dried gel of an inorganic oxide, and the first layer, which is another porous body, are combined, the optimum thickness of the second layer is small. For example, when treating ultrasonic waves with a frequency f of 500 kHz, if the sound velocity C of the dried gel is 50 Om / s, the wavelength of the ultrasonic waves propagating through the dried gel is obtained by C / f, which is 1 mm. .
- the optimal thickness of the acoustic matching member is one-fourth of the wavelength of the ultrasonic wave passing through it, so the optimal thickness of the acoustic matching member consisting of dry gel force is 0.25 mm. It becomes smaller.
- the optimal thickness of the acoustic matching member varies depending on the sound speed, to obtain the optimal acoustic matching member, it is necessary to measure the output after assembling the ultrasonic receiver so that an arbitrary output can be obtained. It is necessary to polish the two layers and adjust the thickness.
- the second layer is a dry gel, the edges of the second layer may be chipped during polishing, It is generally difficult to achieve the thickness.
- the present invention has been made in view of the problems of conventional acoustic matching members, and provides an acoustic matching body having more excellent characteristics, and effectively utilizes a dried gel of an inorganic oxide. It is an object of the present invention to provide an acoustic matching body having a composite structure having excellent characteristics, and to provide a manufacturing method capable of easily manufacturing such an acoustic matching body.
- the characteristics of the acoustic matching body are affected by the pore diameter and the pore size distribution of the porous body.
- it has been found that it is effective to make the pore size distribution uniform.
- the ceramic porous material disclosed in Japanese Patent Application Laid-Open No. 2001-261463. It has been found that when used as a body, excellent properties can be obtained, and the present invention has been completed.
- the present inventors can use the specific porous ceramic body to form a concave portion by molding without performing a cutting process, and the end of the dried gel of the inorganic oxide can be used as the porous ceramic body. It has been found that a configuration protected by is easily obtained.
- the present invention provides an acoustic matching body including a ceramic porous body, wherein the ceramic porous body is
- the ceramic matrix defines a plurality of holes
- an acoustic matching body in which a gap between ceramic particles is formed in the ceramic matrix.
- the ceramic porous body constituting this acoustic matching body has a uniform pore size distribution.
- the porous ceramic body has voids between ceramic particles formed in the ceramic matrix, in addition to pores defined by the ceramic matrix. That is, the ceramic porous body has a structure having many voids in a state of having high strength as a whole, and its density is low.
- the skeleton of the ceramic matrix does not extend linearly, but provides a meandering path to the ultrasonic waves. This reduces the propagation speed of the ultrasonic wave. Therefore, this acoustic matching member has characteristics of low density and low sound velocity, and the ultrasonic sensor using this as an acoustic matching layer has significantly improved ultrasonic wave propagation characteristics.
- the "hole” means a portion that is recognized as a void when a ceramic matrix composed of a plurality of ceramic particles is macroscopically observed (for example, with a microscope with a magnification of about 20).
- the “void between ceramic particles” refers to a minute space formed between the particles constituting the ceramic matrix, and specifically, a small hole having a diameter of 10 ⁇ or less.
- the “holes” can be said to be pores formed by foaming a ceramic slurry according to the method described later, and the “voids between ceramic particles” are in the ceramics regardless of the presence or absence of foaming. It can be said that the holes are formed in the holes.
- acoustic matching body is used to refer to an independent member before being incorporated into an ultrasonic sensor or the like as an acoustic matching layer. ". That is, the "acoustic matching body” and the “acoustic matching layer” are different from each other only in their functions and the like.
- the center value of the pore size distribution is preferably within a range of 100 ⁇ m force and 500 ⁇ m. If the pore size exceeds 500 zm, it may interfere with the propagation of ultrasonic waves. On the other hand, if the hole diameter is less than 100 zm, the propagation of ultrasonic waves will not be hindered. However, as will be described later, an acoustic matching body having a composite structure including this acoustic matching body and another acoustic matching body is required. It may hinder production.
- the other acoustic matching body is formed by impregnating a liquid raw material into the acoustic matching body as described later, if the hole diameter is small, the surface becomes smaller. In some cases, the impregnation does not progress due to the tension, or the solution replacement does not easily progress.
- the porous ceramic body constituting this acoustic matching body has a surface layer and an inner layer continuous with the surface layer, and the density of the surface layer is preferably higher than the density of the inner layer.
- density refers to the density (that is, bulk density) determined from the mass and the apparent volume of a member or element, and “density” in this specification unless otherwise specified. Refers to bulk density. According to this configuration, voids can be eliminated or made smaller in the surface layer, so that when the surface layer is arranged so as to face the gas, the ultrasonic waves can be transmitted to the gas more efficiently, and the surface layer can be formed. When the mounting surface is used, it is possible to prevent the penetration of the adhesive and to reduce the variation in the ultrasonic output between the ultrasonic sensors due to the penetration of the adhesive.
- the ceramic matrix preferably contains a non-sinterable ceramic.
- the non-sinterable ceramic preferably accounts for 80 vol% of the ceramic matrix, more preferably 90 vol%, and still more preferably 100 vol%.
- the present invention also provides, in the second aspect, an acoustic matching body including a first porous body and a second porous body,
- the first porous body is a first porous body
- the ceramic matrix defines a plurality of holes
- the ceramic matrix is a porous ceramic body in which voids between ceramic particles are formed
- An acoustic matching body wherein the second porous body is a porous body having a lower density and a lower sound velocity than the first porous body.
- the matching of the acoustic impedance with the gas is further improved by the second porous body.
- the pores have a size such that the median value of the pore size distribution is in the range of 100 ⁇ m to 500 ⁇ m. ,. If the first porous body has pores of such dimensions, as will be described later, when the second porous body is integrally combined with the first porous body by a method of impregnating the starting material solution of the second porous body. Then, the raw material solution of the second porous body is easily impregnated. Holes of such dimensions, for example, have a frequency of 5 This does not hinder the propagation of the 00 kHz ultrasonic wave.
- the second porous body is preferably formed of a dried gel of an inorganic oxide.
- the second porous body can have a lower density than the first porous body, and the bonding between the first porous body and the second porous body can be strengthened. it can.
- the acoustic matching body having the composite structure it is preferable that an outer peripheral portion of the second porous body is surrounded by the first porous body. That is, the contour of the second porous body in the surface direction (that is, the contour that determines the surface area of the second porous body) is preferably in contact with the first porous body. Thus, the outer edge of the second porous body is prevented from being chipped, and for example, the thickness of the acoustic matching body having the composite structure can be controlled by polishing the surface on which the second porous body is located.
- the second porous body preferably fills a part or all of the pores of the first porous body and the voids between the ceramic particles. Thereby, the second porous body is more strongly bonded to the first porous body by the anchor effect.
- the present invention provides, in the third aspect, gelling a bubble-containing ceramic slurry having at least one kind of hardly sinterable ceramic powder in a molding die to obtain a gel-like porous molded body;
- a method for manufacturing an acoustic matching body is characterized by the use of hardly sinterable ceramic powder and the gelling of an aerated ceramic slurry.
- the ceramic porous body provided in the first aspect can be easily manufactured.
- the volume of the ceramic porous body finally obtained by firing only changes by about a few percent from the volume of the gel-like porous molded body before firing, and therefore, the warpage generated after firing. Can be reduced.
- the present invention provides, in the fourth aspect, a bubble-containing ceramic having a non-sinterable ceramic powder. Gelling the slurry in the first mold to obtain a gel-like porous molded body having one or more concave portions;
- This manufacturing method is characterized in that one or more recesses for disposing the second porous body are formed in the gel-like porous molded body before firing.
- the first porous body can be manufactured with a small change in volume before and after firing, even if the recess is formed in advance, a recess having a desired size is obtained in the finally obtained first porous body. It can be obtained with high accuracy.
- the depth of the concave portion is hard to change particularly before and after firing. This enables the second porous body requiring dimensional accuracy to be formed in the recess with a desired and uniform thickness.
- this manufacturing method makes it possible to obtain a configuration in which the second porous body having a predetermined size is integrated with the first porous body.
- this manufacturing method does not require cutting the first porous body to form the concave portion, according to this manufacturing method, the outer peripheral portion of the second porous body is surrounded by the first porous body. The configuration can be easily obtained.
- the first porous body has a gap between ceramic particles that is formed only by the pores defined by the ceramic matrix, and the starting material of the second porous body is provided in the pores and the gap.
- the solution permeates to form a second porous body. Therefore, the finally obtained second porous body exerts a higher anchoring effect and is more strongly bonded to the first porous body.
- the first porous body is disposed in the second mold so that the bottom surface of the second mold and the concave portion face each other. That is, the concave portion of the first compact is It is preferable to form a closed space with the bottom of the mold.
- drying of the gel-like porous molded body formed by the first molding die is performed by using the side, upper, and lower surfaces of the gel-like porous molded body. It is preferable to open the first mold on at least one surface. Thereby, the drying of the gel-like porous compact can be performed more efficiently.
- This drying method is preferably applied not only when obtaining an acoustic matching body having a composite structure but also when manufacturing an acoustic matching body having a single-layer structure (that is, the acoustic matching body provided in the first aspect). You.
- the first mold it is preferable to open the first mold by sliding the mold wall of the first mold.
- the method of sliding the mold wall of the molding die it is possible to effectively suppress the deformation of the gel-like porous molded body in the drying step, and to prevent the surface of the gel-like porous molded body from being damaged. Can be exposed.
- the concave portion formed in the first porous body is formed after the cell-containing ceramic slurry is poured into the first mold. That is, it is preferable to pour the bubble-containing ceramic slurry into the first mold having no convex portion for forming the concave portion, and then perform embossing or the like necessary for forming the concave portion.
- a molding die in which at least a portion of a gel-like porous molded body that comes into contact with at least one surface is made of resin is used as a first molding die used for forming the first porous body. Is preferred. By appropriately selecting the material of the resin on the surface in contact with the gel-like porous molded body, the surface state of the gel-like porous molded body can be changed.
- the use of a mold in which the surface in contact with the gel-like porous molded body is made of a resin is not only required to obtain an acoustic matching body with a composite structure, but also a single-layered acoustic matching body (that is, provided in the first gist).
- the present invention is also preferably applied to the case of manufacturing an acoustic matching body to be manufactured.
- a portion in contact with at least one surface of the gel-like porous molded body is made of metal. It is preferable to use a mold. By making the surface in contact with the gel-like porous molded body a metal, pores (bubbles of the aerated ceramic slurry) are less likely to be present on the surface of the gel-like porous molded body, and a dense surface layer can be formed. Can be.
- the use of a mold in which the surface in contact with the gel-like porous molded body is made of metal is not only required to obtain an acoustic matching body having a composite structure, but also to provide a single-layered acoustic matching body (that is, provided in the first gist).
- the present invention is also preferably applied to a case where an acoustic matching body is manufactured.
- an acoustic matching body having a single-layer structure that is, an acoustic matching body provided in the first aspect
- a multilayer structure including a piezoelectric body and an acoustic matching layer is provided.
- An ultrasonic sensor is provided in which the acoustic matching body (that is, the acoustic matching body provided in the second aspect) is an acoustic matching layer. This ultrasonic sensor can transmit and receive ultrasonic waves satisfactorily and reliably by including the acoustic matching body of the present invention.
- the acoustic matching layer includes a piezoelectric body and an acoustic matching layer, and the acoustic matching layer includes the single-layered acoustic matching body (ie, the acoustic matching body provided in the first aspect).
- the present invention provides an ultrasonic transmitting / receiving device which is an acoustic matching body having the above-mentioned multilayer structure (ie, the acoustic matching body provided in the second aspect). This ultrasonic transmitting and receiving apparatus can transmit and receive ultrasonic waves satisfactorily and reliably by including the acoustic matching body of the present invention.
- the acoustic matching body of the present invention is characterized in that it has a hole defined by a ceramic matrix and an interparticle gap formed in the ceramic matrix. Since this acoustic matching body is made of an inorganic material as its main material, its characteristic change due to temperature is smaller than that of resin. If this is incorporated into the ultrasonic sensor as an acoustic matching layer, the ultrasonic sensor will have a good temperature. Shows characteristics (ie, performance change with temperature is small). In addition, since the density and porosity of this porous ceramic body can be easily adjusted, the acoustic matching body of the present invention can be adjusted so as to have the optimum characteristics for being incorporated into a predetermined ultrasonic sensor. Can be configured.
- acoustic matching with gas is further improved by combining a porous ceramic body and a porous inorganic oxide body. Therefore, by incorporating the acoustic matching body having such a composite structure as the ultrasonic matching layer of the ultrasonic sensor, it is possible to improve the transmission and reception efficiency of the ultrasonic wave. Also, this super For example, if an ultrasonic transmitting / receiving device using an acoustic wave sensor is used as a gas flow measuring device, the ratio between the main signal and the noise signal can be reduced, the measurement accuracy of the device can be increased, and the amplification of the received signal can be improved. Therefore, the circuit can be simplified.
- FIG. 1 (a) is a micrograph showing a cross section of a porous ceramic body constituting an acoustic matching body of Embodiment 1 of the present invention
- FIG. 1 (b) is an acoustic matching body of Embodiment 1 of the present invention. It is a schematic diagram which shows the cross section of the ceramics porous body which comprises.
- FIG. 2 (a) is a micrograph showing an enlarged cross section of a ceramic porous body constituting the acoustic matching body of Embodiment 1 of the present invention
- FIG. 2 (b) is a micrograph of Embodiment 1 of the present invention
- FIG. 2 is a schematic diagram showing an enlarged cross section of a porous ceramic body constituting an acoustic matching body.
- FIG. 3 is a process drawing illustrating a method for manufacturing an acoustic matching body of Embodiment 1 of the present invention.
- FIG. 4 is a cross-sectional view schematically showing the acoustic matching body of Embodiment 1 of the present invention.
- FIGS. 5 (a) and (b) are cross-sectional views each schematically showing an example of an ultrasonic sensor using the acoustic matching body of Embodiment 1 of the present invention as an acoustic matching layer.
- FIG. 6 (a) is a cross-sectional view schematically showing an acoustic matching body of Embodiment 2 of the present invention
- FIG. 6 (b) is an acoustic matching layer of Embodiment 2 of the present invention. It is sectional drawing which shows an example of an ultrasonic sensor typically.
- FIG. 7 is a process diagram showing an example of a method for producing a second porous body constituting the acoustic matching body of Embodiment 2 of the present invention.
- FIG. 8 is a schematic view showing a method of manufacturing the acoustic matching body of Embodiment 2 of the present invention as Embodiment 3 of the present invention.
- FIG. 9 is a cross-sectional view schematically showing a part of an acoustic matching body manufactured according to a third embodiment of the present invention.
- FIG. 10 is a schematic view showing one step performed in the method of manufacturing the first porous body constituting the acoustic matching body of the present invention, which is the fourth embodiment of the present invention.
- FIG. 11 is a schematic view showing a step performed after the step shown in FIG. 10 is performed.
- FIG. 12 is a schematic view showing a step performed after the step shown in FIG. 11 is performed.
- FIG. 13 is a schematic view showing a step performed after the step shown in FIG. 12 is performed.
- FIG. 14 is a block diagram showing a structure of an ultrasonic flowmeter according to a fifth embodiment of the present invention.
- FIG. 15 is a waveform diagram obtained by the ultrasonic flowmeter according to the fifth embodiment of the present invention.
- FIG. 16 is a cross-sectional view schematically showing a conventional ultrasonic sensor.
- FIG. 1 is a micrograph showing a cross section of the ceramic porous body constituting the acoustic matching body of the present invention, and (b) is a cross section of the ceramic porous body constituting the acoustic matching body of the present invention.
- 1 is a ceramic porous body (acoustic matching body)
- 2 is a ceramic matrix
- 3 is a hole defined by the ceramic matrix 2
- 4 is a surface layer
- 5 is an inner layer.
- the ceramic matrix 2 is an enlarged view of a part of the ceramic matrix 2, (a) is a micrograph showing an enlarged cross section of the ceramic matrix, and (b) is a schematic diagram showing an enlarged cross section of the ceramic matrix.
- reference numeral 6 denotes ceramic particles
- reference numeral 7 denotes voids between ceramic particles.
- the ceramic matrix 2 is composed of known oxide-based or non-oxide-based ceramics, clay mineral, or the like.
- the ceramic matrix is composed of these ceramic components alone or in combination of two or more. Examples of oxide ceramics include alumina, mullite, and zirconia.
- Non-oxide ceramics include silicon carbide, silicon nitride, aluminum nitride, boron nitride, and boron nitride. And graphite.
- the ceramic matrix 2 is a skeleton that defines the plurality of holes 3, and a part or all of the skeleton is made of ceramic particles.
- the ceramic matrix 2 has a structure in which, for example, ceramic particles (for example, silicon carbide particles) are bonded to each other, and it is considered that such a structure is obtained by bonding the ceramic particles via oxygen.
- the ceramic particles are bonded means that the ceramic particles are in contact with each other so that sound waves are propagated. Ceramic particles are generally bonded in the firing step.
- the average particle size of the particles constituting the ceramic matrix is preferably 10 / m or less, more preferably 5 / im or less, further preferably ⁇ or less, and 0.6 ⁇ m or less.
- the average particle size of the ceramic particles constituting the ceramic matrix exceeds 10 ⁇ m, the dispersibility of the particles in the slurry may decrease when an acoustic matching body is manufactured according to the method described below.
- the holes 3 defined by the ceramic matrix 2 correspond to bubbles generated by a foaming agent in the ceramic slurry when the acoustic matching body is manufactured according to a method described later. As described above, these holes are recognized as holes when the cross section of the acoustic matching body is observed at a magnification of about 20 times. In order for this ceramic porous body to function as an acoustic matching layer in an ultrasonic sensor or the like, it is necessary to appropriately select the size of the hole 3. Specifically, the size of the hole 3 needs to be sufficiently smaller than the wavelength of the ultrasonic wave propagating through the acoustic matching body.
- the frequency f of the ultrasonic wave is 500 kHz and the sound speed C of the acoustic matching body is 2000 m / s
- the size of the hole of the acoustic matching body is 300 ⁇ m or more, the effect of the hole 3 becomes large with respect to the propagation of the ultrasonic wave, and the energy of the ultrasonic wave output from the acoustic matching body decreases. .
- the acoustic matching body of the present invention is preferably configured to have such a size that the center value of the hole diameter distribution of the hole 3 is 300 / m or less.
- the hole 3 should have such a size that the center value of the hole diameter distribution is within the range of 100 ⁇ m to 500 ⁇ m. It is preferably formed.
- the hole diameter of the hole 3 is determined from the cross-sectional photograph of the porous ceramic body as the largest line segment among the line segments connecting any two points of the ring ⁇ of the hole.
- the pore size distribution of the pores is desirably determined by measuring the pore size for an arbitrary 100,000 pores.
- this acoustic matching body there are minute gaps 7 between the ceramic particles between the ceramic particles 6.
- This void is microscopic and its pore size is less than 10 x m.
- the ceramic particles 6 are partially bonded with glass interposed therebetween, or the ceramic particles 6 are bonded without glass with interposed glass.
- ceramic porous body 1 having such a hole 3 and the ceramic interparticle voids 7 have a density of about 0 ⁇ 4 one 0 ⁇ 8 g / cm 3, the sound velocity C is 2000 m / s-about 3000 m / Since it is about s, it can function as an acoustic matching body.
- This porous ceramic body 1 has a porosity of preferably 60 vol% or more, more preferably 90 vol% or more, including the pores 3 and the voids 7 between the ceramic particles.
- the illustrated porous ceramic body 1 has a surface layer 4 and an inner layer 5 continuous with the surface layer.
- the surface layer 4 is a dense layer in which the holes 3 are not formed or the ratio of the holes 3 is smaller than that of the inner layer 5, and gives a smooth surface.
- the surface layer 4 preferably has a density of 2.5 to 8.5 times the density of the inner layer.
- the surface layer 4 preferably has a thickness of about 10 30 xm. When the thickness of the surface layer 4 exceeds 30 zm, the effect of the surface layer 4 on the ultrasonic wave propagation increases. It is generally difficult to make the thickness of the surface layer 4 smaller than 10 ⁇ m.
- the surface layer 4 may be disposed on the gas side in an ultrasonic sensor or the like as described later.
- the surface layer 4 has a high density and is thin, it does not significantly affect the acoustic impedance.However, if it is placed on the gas side, the gas will have a smooth surface. Since it is pushed, the ultrasonic waves can be efficiently transmitted to the gas 20.
- the surface layer 4 may be arranged so as to face the transducer mounting member (that is, the container). In this case, the surface layer 4 without or with a small number of holes effectively prevents the adhesive from penetrating into the acoustic matching body 1.
- the ceramic porous body 1 In order to function as an acoustic matching body, the ceramic porous body 1 needs to have a sufficiently strong bond between ceramic particles. In the ceramic porous body 1 in which the bond between the ceramic particles is weak, ultrasonic waves are transmitted and the porous body becomes brittle.
- the ceramic porous body in which the pores 3 having the above-described dimensions and the voids 7 between the ceramic particles are formed and the bonding between the ceramic particles is sufficiently strong includes, for example, a ceramic powder that is difficult to sinter. It is manufactured by subjecting a gel-like porous molded body obtained by gelling an aerated ceramic slurry to a drying, degreasing, and firing step. The manufacturing method will be described with reference to FIG.
- the method for manufacturing an acoustic matching body of the present invention comprises the steps of baking a mixed slurry (step 11), preparing a bubble-containing slurry (step 12), forming step (step 13), and drying step. (Step 14), degreasing and firing process (Step 15), and cutting process (Step 16).
- the steps specifically performed in each step are described as a flowchart on the right side of the figure.
- the materials used in each step are described in the middle row in the figure.
- a mixed slurry is prepared by mixing and pulverizing ceramic powder (for example, silicon carbide and glass) and water (an organic solvent is mixed if necessary) as input materials, for example, with a ball mill. And a defoaming step of defoaming the obtained mixed slurry.
- the ceramic powder has at least one kind of hardly sinterable ceramic powder.
- the non-sinterable ceramic powder is, for example, silicon carbide.
- the non-sinterable ceramic preferably accounts for 80 vol%, more preferably 90 vol%, and more preferably 100 vol% of the entire ceramic powder. As the proportion of the non-sinterable ceramics increases, the volume change can be reduced in the subsequent firing step, and warpage does not easily occur. Grinding is performed so that the particle size is uniform. Defoaming is performed in a glove box or the like filled with nitrogen. Therefore, before the defoaming step, a degassing 'nitrogen substitution step is performed.
- step 12 a surfactant (foaming agent) and gelation are added to the mixed slurry in a nitrogen atmosphere.
- This is a foaming step in which the agent is added and mixed with a stirrer.
- the type of surfactant, the type of ceramic powder, the stirrer speed, the stirring time and the temperature are determined by the size and distribution of the aerated bubbles (that is, the pores defined by the ceramic matrix in the porous ceramic body). Is a parameter for determining Therefore, it is necessary to appropriately select these parameters so as to obtain a desired hole.
- This step is an important step in determining the porous structure.
- Step 13 is a step of transferring the obtained cell-containing ceramic slurry to a molding die having an arbitrary shape and gelling to form a gel-like porous molded body. Gelation proceeds by leaving the slurry in a closed mold for tens of minutes.
- the mold may be, for example, a cylinder having a diameter of about 10 to 20 mm, particularly 10.8 mm.
- Step 14 is a step for removing the gel-like porous molded body from the mold and removing water and some organic components.
- the gel-like porous molded body is so strong (solidified) that it can be held by hand, and is easy to handle.
- step 14 may be performed by sliding a part of the mold wall of the mold to expose at least one of the upper surface, the lower surface, and the side surface of the porous gel body. This eliminates the need to take out the gel-like porous molded body from the molding die, so that the possibility of damaging the gel-like porous molded body can be reduced.
- Drying is preferably performed so that bubbles contained in the gel-like porous molded body do not decompose, move, or aggregate.
- Step 15 is a degreasing step of heating to a temperature necessary to remove excess organic components contained in the dried porous molded body, and a step of bonding the ceramic powder to form a matrix. And a firing step of firing at a high temperature.
- the temperature and time for degreasing are determined according to the type and amount of the organic component used.For example, in order to burn off the gelling agent, treatment is performed at 400 700 ° C for 24 to 48 hours. You may.
- the firing temperature is determined according to the ceramic powder used (ie, glass or non-sinterable ceramic powder). For example, when using silicon carbide and a glass having a lower melting point than the ceramic powder, firing is performed at, for example, about 800 ° C.
- the firing time For example, it can be 12-48 hours.
- the firing temperature may be 900 ° C to 1350 ° C, and the firing time may be, for example, 12 to 48 hours.
- Step 16 is a step of cutting the obtained fired body (porous ceramic body) to a size necessary for it to function as an acoustic matching body.
- the structure having the surface layer 4 and the inner layer 5 in one ceramic porous body is formed by the foaming step and the step 13 in the preparation step of the bubble-containing ceramic slurry in step 12 shown in FIG.
- the force S can be formed by a method of obliquely orienting bubbles. Specifically, the inclined orientation of the bubbles is performed in step 11 by adjusting the solid content or the viscosity of the mixed slurry.
- a portion that comes into contact with the cell-containing slurry that is, a surface that comes into contact with at least one surface of the solidified gel-like porous molded body.
- a mold made of resin or metal bubbles cannot exist in the ceramic slurry at the interface with the mold.
- the portion where this bubble cannot exist is formed as the surface layer 4.
- a PET resin is selected as the resin
- a dense surface layer 4 can be formed.
- the metal for example, stainless steel can be selected.
- the surface layer formed by the contact of the bubble-containing slurry with the metal surface tends to be thicker than the surface layer formed by the contact with the resin surface.
- the surface of the mold is made of, for example, Teflon (registered trademark)
- Teflon registered trademark
- the porous ceramic body produced in this manner has the pores 3 such that the center value of the pore diameter distribution is within the range of 100 xm force 500 xm, and the porosity is about 60 vol% or more.
- bulk Density of about 0. 4g / cm 3 - the 0.5 is 8 g / cm 3 structure.
- a plurality of holes 3 are connected to form a communication hole.
- the sound velocity of this structure is about 2000m / s to about 3000m / s as described above, so this structure can be used as an acoustic matching layer.
- FIG. 4 schematically shows a cross-sectional view of the acoustic matching body of the present invention.
- Figure 4 shows a cylindrical acoustic matching body with a diameter of 10.8 mm, which is processed to have a thickness of about lmm and about 1.5 mm.
- FIG. 4 shows a form having no surface layer, but the surface layer as shown in FIG. 1 is formed on one main surface (surface perpendicular to the thickness).
- the surface layer may be formed on both main surfaces, but in that case, it is necessary that the thickness of the molded body obtained after performing step 15 in FIG. 13 has a desired thickness. This is because if the main surface is polished by cutting to obtain a desired thickness, one surface layer will be cut off. As shown in FIG.
- the surface layer when obtaining a structure in which the surface layer is not located on any surface, the surface layer is not formed by appropriately selecting the material constituting the exposed surface of the mold. Like that. Alternatively, the surface layer may be scraped off when the ceramic porous body after firing has a predetermined thickness.
- FIGS. 5A and 5B are cross-sectional views of an ultrasonic sensor using the acoustic matching body of a porous ceramic body manufactured in this manner.
- 5 (a) and 5 (b) 1 denotes a porous ceramic body (acoustic matching layer), 17 denotes a vibrator, 18 denotes a vibrator mounting member, 19 denotes a bonding means, and 20 denotes a gas.
- the illustrated ceramic porous body 1 has a structure having a surface layer 25 and an inner layer 26.
- FIG. 5A shows an ultrasonic sensor in which the surface layer 25 is arranged on the gas side
- FIG. 5B shows an ultrasonic sensor in which the surface layer 25 is arranged so as to be in contact with the bonding means 19.
- the bonding means is, for example, an epoxy adhesive.
- the vibrator mounting member 18 is made of metal, and the vibrator 17 is arranged in a closed space by mounting a cap 21.
- the cap 21 is made of metal, and the terminal 22 is attached to the cap 21 so that the upper electrode of the vibrator electrode provided above and below the vibrator 17 is electrically connected to the terminal 22. State.
- the lower electrode of the vibrator 17 is electrically connected to the other terminal 24 via the conductive rubber 23.
- Terminal 24 is insulated from cap 21.
- the porous ceramic body (acoustic matching layer) 1 has a configuration that can be divided into a surface layer 25 and an inner layer 26.
- the surface layer 25 has a denser structure than the inner layer 26, and has a force with extremely few holes or a layer without holes.
- the thickness of the surface layer 25 is about 10-30 ⁇ m.
- the method for manufacturing the porous ceramic body having the surface layer 25 and the inner layer 26 is as described above with reference to FIG. 3, and thus description thereof will be omitted.
- the bonding between the ceramic porous body (acoustic matching layer) 1 and the vibrator mounting member 18 is performed using a bonding means 19, for example, an epoxy adhesive. If there is a hole in the bonding surface of the ceramic porous body (acoustic matching layer) 1, the epoxy adhesive may penetrate and uneven bonding may occur. When the adhesion unevenness occurs, there is a disadvantage that the ultrasonic output of the ultrasonic sensor having the same specification varies. In order to avoid inconvenience, the surface of the surface layer 25 may be used as a joint surface with the transducer mounting member 18 as shown in FIG.
- FIG. 6A shows an acoustic matching body having a composite structure as a second embodiment of the present invention
- FIG. 6B shows an ultrasonic sensor using the acoustic matching body as an acoustic matching layer.
- the acoustic matching body 44 shown in FIG. 6 (a) is a disk having a diameter of 10.8 mm and a thickness of 1.8 mm, and has the ceramic porous body described above as the first porous body 42 and the first porous body 42. It has a composite structure in which the recesses formed in the body 42 are filled with the second porous body 43.
- the first porous body 42 has a ceramic matrix 41 serving as a skeleton, and a force cell illustrated as a structure in which the pores 40 are defined by the ceramic matrix 41. As described with reference to FIG. 1, the gap between the ceramic particles is formed in the mix matrix 41.
- the ceramic porous body 42 is a gel-like porous molded body obtained by gelling a cell-containing ceramic slurry having a hardly sinterable ceramic powder (for example, silicon carbide powder). It is made by drying, degreasing and firing the body.
- a plurality of The holes 40 are connected to form a communication hole.
- the second porous body 43 is a porous body having a lower density and a lower sound velocity than the first porous body 42.
- the acoustic matching body of the second embodiment can increase the ultrasonic output more than the acoustic matching body of the first embodiment.
- the second porous body 43 is preferably a dried gel of an inorganic oxide such as silica.
- an inorganic oxide such as silica
- step 51 the dried silica gel was subjected to a raw material preparation step (step 51), a gelation step (step 52), a density adjustment step (step 53), a hydrophobic treatment step (step 54), and a It is roughly divided into a drying process (step 55).
- step 51 the steps specifically performed in each step are shown as a flowchart in the middle column in the figure.
- step 53 the density adjustment step
- step 54 a hydrophobic treatment step
- step 55 the steps specifically performed in each step are shown as a flowchart in the middle column in the figure.
- the materials input in each step are shown in the right column in the figure.
- Step 51 is a step of preparing a mixed solution by adding water, ethanol, and hydrochloric acid for hydrolyzing tetraethoxysilane, which is a main raw material.
- Step 52 is a step of producing a gel by adding ammonia to the prepared mixed solution.
- silica is polymerized as a monomer to form a porous gel
- Step 53 is a step of enhancing the skeleton of the obtained gel to an arbitrary density.
- tetraethoxysilane, water, ethanol, and ammonia are added, and the hydrolysis reaction proceeds again, thereby enhancing the gel skeleton.
- the gel is controlled to a desired density by controlling the reaction time and temperature. Replacing the solution with isopropyl alcohol stops the reaction for enhancing the skeleton of the gel.
- Step 54 is a process for preventing the finally obtained dry gel force from absorbing moisture.
- the gel is put into a silane coupling treatment solution to progress the silane coupling reaction, and then the solution is replaced with isopropyl alcohol to stop the silane coupling reaction.
- Step 55 is a final step of evaporating isopropyl alcohol to obtain a dried gel.
- dry gel made through such manufacturing process has a porosity of nanometer size, density is adjusted from 0. 2 g / cm 3 to 0. 5 g / cm 3, the sonic velocity 300 meters / From 500 s to 500 m 2 / s, the acoustic impedance of this dried gel can be smaller than the acoustic impedance of the ceramic porous body as the first porous body.
- the second porous body 43 is arranged in a concave portion formed in the first porous body 42.
- the edge of the second porous body 43 is protected by the first porous body. Therefore, by adopting this composite structure, the edge of the second porous body 43 can be effectively prevented from being chipped. For example, by polishing the surface of the second porous body 43, the thickness D thereof can be easily reduced. The desired thickness can be obtained.
- the second porous body 43 when the second porous body 43 is formed of a dried gel of silica, the second porous body 43 has a shape of about 8 mm in diameter and 0.15 to 0.4 mm in thickness, and has a diameter of about 10.8 mm.
- the first porous body 42 is formed.
- the second porous body 43 having the force and the required dimensions forms a shallow concave portion having the above-mentioned diameter in the first porous body 42, and after the second porous body 43 is arranged in the concave portion by a method described later, It is obtained by a method of polishing both surfaces of the porous body 42 and the second porous body.
- a plurality of recesses (for example, a plurality of ring-shaped recesses having different diameters) are formed in the first porous body, and the second porous body 43 is provided at a plurality of locations (for example, rings having different diameters). ).
- FIG. 6 (b) shows the structure of an ultrasonic sensor using the composite acoustic matching layer 44.
- the ultrasonic sensor shown in FIG. 6 (b) has the same structure as the ultrasonic sensor shown in FIG. 5 (a), and the same reference numerals as those used in FIG. 5 (a) indicate the same elements or members.
- the acoustic matching layer has a composite structure
- the second porous body 43 has a lower density than the first porous body 41.
- the ultrasonic output can be increased as compared with the ultrasonic sensor using the body.
- FIG. 8 schematically shows a method for manufacturing an acoustic matching body having a composite structure according to a third embodiment of the present invention.
- FIG. 8 shows a state where the first porous body 42 in which the concave portion 63 for arranging the second porous body therein is formed is placed on the mold 61 with the concave portion 63 down, and is housed in the container 62. .
- the mold 61 used here and the mold used to form the first porous body 42 In order to distinguish between the first and second molds, the mold for forming the second molded body is referred to as a second mold for convenience, and the mold for forming the first molded body is referred to as a first mold for convenience. When you call you have power S.
- the molding die 61 is a second molding die.
- the container 62 is filled with the starting material solution 64 prepared in step 51 shown in FIG. 7 and described in relation to the second embodiment.
- the solution 64 penetrates through the communication holes of the first porous body 42, which is a ceramic porous body, and as a result, the recess 63 is filled with the solution 64.
- Step 52 shown in FIG. 7 is performed in this state.
- the communication holes of the first porous body 42 are formed by continuous cells generated by the connection between the pores defined by the ceramic matrix, the connection between the pores and the gap between the particles, and the connection between the gaps between the particles. It is.
- FIG. 9 is an enlarged view of a part of the first porous body 42 placed on the mold 61 shown in FIG. Since the recesses 63 formed in the first porous body 42 are filled with the solution that has penetrated the communication holes of the first porous body 42, the gel is also filled in the communication holes of the first porous body 42 (this gel is eventually To form the porous body 43). The gel formed in the recess 63 is also in contact with the mold 61. In FIG. 9, only the holes 66 defined by the ceramic matrix 65 are shown, and communication holes are formed in the force holes 66 indicating the communication holes formed by the ceramic matrix 65, the gap between the ceramic particles, and the gap between the ceramic particles. It should be noted that it is formed.
- step 53 Since density adjustment is performed in step 53 with this arrangement, a newly added mixed solution of tetraethoxysilane, water, ammonia, and ethanol is also formed in the hole 66 of the first porous body 42. After passing through the gel, the gel formed in the concave portion 63 is reached, and the skeleton of the gel in the concave portion 63 and the pore 66 is strengthened. After that, it is carried out with this arrangement until step 54.
- the solution and the solvent used in each step pass through the gel formed in the hole 66 of the first porous body 42 and reach the recess 63. That is, the solution or the like that has passed through the gel formed in the hole 66 strengthens the skeleton of the gel formed in the concave portion 63 or stops the reaction that is proceeding in the gel. Therefore, if the pores 66 of the first porous body 42 are too small, the permeation of the solution will be insufficient, and the gel 43 formed in the recess 63 will not reach the gel 43. Also, if the hole 66 of the first porous body 42 is too large, it will interfere with the propagation of ultrasonic waves. Come.
- the first porous body 42 is preferably formed such that the center value of the pore diameter distribution of the pores 66 defined by the ceramic matrix is between 100 ⁇ m and 500 ⁇ m.
- the adjustment of the dimension of the hole 66 of the first porous body 42 is performed in the step of preparing a bubble-containing slurry, which is Step 12 in FIG.
- the second porous body is formed by impregnating the necessary material so as to pass through the communication holes formed by the pores defined by the matrix of the ceramic porous body as the first porous body.
- this method it is possible to perform a drying step for obtaining the second porous body in a state where the recess formed in the first porous body and the surface of the molding die form a closed space.
- cracks occur in the gel during the formation of the second porous body.
- an inorganic oxide gel is manufactured as a single gel in accordance with the manufacturing method shown in FIG. 7, the gel surface is in an exposed state.
- the portion to be the second porous body is protected by the first porous body and is less susceptible to stress, so that cracks can be prevented. Further, since the second porous body is formed in a state of being in contact with the molding die as shown in FIG. 9, its surface becomes extremely smooth when the surface of the molding die is smooth.
- the acoustic matching body obtained by this manufacturing method has a structure in which at least a part of the pores defined by the matrix of the first porous body and the gap between the ceramic particles in the matrix is filled with the second porous body. It will be. Therefore, the first porous body has a higher density than the acoustic matching body described in the first embodiment.
- the first porous body is preferably a single body because the acoustic impedance of the first porous body is preferably between the acoustic impedance of the second porous body and the acoustic impedance of the oscillator.
- the density of the ceramic porous body which is the first porous body, can be easily adjusted by adjusting the porosity, the density of the ceramic porous body can be adjusted to have a desired acoustic impedance according to the type of the second porous body. It is easy to manufacture the first porous body.
- FIGS. 10 to 13 schematically show a method of manufacturing a first porous body of an acoustic matching body having a composite structure according to a fourth embodiment of the present invention.
- These figures show a process for producing a gel-like porous molded body by gelling an aerated slurry containing a ceramic powder having difficulty in sintering, and a molding die (ie, a first mold) used for performing the process. Mold).
- the molding die 70 shown in FIG. 10 includes an upper surface 71, a side surface 73, a movable bottom surface 75, and a fixed bottom surface 74 serving as a mold wall, and a guide portion 72 and a spacer 76.
- the cell-containing ceramic slurry 77 is poured into a portion surrounded by the side surface portion 73, the fixed bottom portion 74, and the moving bottom portion 75.
- the moving bottom portion 75 is raised by the spacer 76, and the bottom portions 24 and 25 are flush. Therefore, when the bubble-containing ceramic slurry 77 was gradually poured from the center, the slurry spread to every corner of the mold, and was surrounded by the side 73, the fixed bottom 74, and the moving bottom 75 where no gas remained. Fill the part. From this state, when the spacer 76 is removed as shown in FIG.
- the bubble-containing ceramic slurry is raised when the side surface portion 73 and the moving bottom surface portion 75 slide. As shown in FIG. 12, the raised slurry 77 is removed by flattening the upper surface portion 21 by moving the upper surface portion 21 downward and pushing out an excess amount from the inside of the mold. In this state, the cell-containing ceramic slurry 77 is gelled. After the gelation is completed, the side surface 73 is slid upward as shown in FIG. 11 to open the side surface of the gel-like porous molded body. Thereby, the moisture contained in the gel-like porous molded body is easily evaporated, and the drying time is shortened. In addition, by sliding the side portion 73 upward to expose the surface of the gel-like porous molded body, the gel can be dried without damaging the surface of the gel.
- the upper surface portion 71 is moved upward to take out the dried gel-like porous molded body 77. Thereafter, the porous gel body is fired to obtain a ceramic porous body.
- This ceramic porous body has, for example, a diameter of 10.8 mm, It is formed so as to have a disk shape with a thickness of 1.8 mm.
- the porous portion of the ceramic porous body bubbles formed in the cell-containing slurry form communication holes after firing.
- the porous ceramic body obtained in this way forms the first porous body 42 in the acoustic matching body having the composite structure shown in FIG. 6 (a).
- the surface of the first porous body that comes into contact with the upper surface 71 is a surface that is bonded to the vibrator mounting member 18 of the ultrasonic sensor shown in FIG. 6B with an adhesive. Therefore, if a hole is present on this surface, the adhesive may penetrate when assembling the ultrasonic sensor, which may cause inconvenience.
- the surface of the upper surface portion 71 in contact with the first porous body is made of, for example, a surface made of PET resin or metal to avoid the inconvenience and the inconvenience. This makes it difficult for air bubbles to exist, whereby a dense and thin surface layer having no or little pores can be formed. This surface layer provides a dense surface as described above to prevent the penetration of the adhesive and to provide a secure bond.
- the surface of the molding die is made of Teflon (registered trademark)
- Teflon registered trademark
- a surface having holes is easily formed without forming a dense surface layer. Therefore, if the fixed bottom part 74, the moving bottom part 75, and the side part 73 are formed of Teflon (registered trademark), pores exist on the surface that comes into contact with them during the gelation process of the bubble-containing ceramic slurry. It becomes.
- the second porous body can be formed by the above-described manufacturing method shown in FIG.
- the surface of the first porous body 42 where the second porous body is not located becomes a hole part. It is a dense surface with few pores, and the side and bottom surfaces are surfaces where holes exist. Therefore, when the second porous body is formed by the manufacturing method shown in FIG. 8, the solution 64 passes through the pores on the side surfaces of the first porous body 42 and is gelled in the concave portions and the pores.
- the surface of the first porous body not in contact with the second mold can be used as a joint surface when assembling the ultrasonic sensor.
- FIG. 14 is a circuit block diagram showing a state in which the ultrasonic transmitting and receiving apparatus of the present invention is incorporated in a flow rate measuring apparatus 88 for measuring a gas flow rate. It is a lock figure.
- An ultrasonic sensor A82 and an ultrasonic sensor B83 are arranged in a flow path 81 through which gas flows.
- the ultrasonic sensors A and B are arranged such that the ultrasonic wave propagation path forms an angle ⁇ with the gas flow path.
- a transmission signal is sent from the transmission means 84 to the ultrasonic sensor A81 and the ultrasonic sensor B83.
- the reception signal of the ultrasonic sensor is transmitted to the receiving means 85. Transmission and reception are selected by the switching means 87. When the switching means 87 selects to connect the ultrasonic sensor A 82 to the transmitting means 84, the ultrasonic sensor B83 is connected to the receiving means 85.
- FIG. 15 is a waveform diagram showing waveforms of a transmission signal and a reception signal of the ultrasonic sensor.
- a transmission signal to the ultrasonic sensor ⁇ is indicated by a-1.
- the received signal is indicated by a-2.
- the ultrasonic sensor B83 transmits ultrasonic waves and the ultrasonic sensor A82 receives ultrasonic waves
- the transmission signal power to the ultrasonic sensor B 3 ⁇ 4_1 is indicated, and the ultrasonic sensor A82 Is indicated by b-2.
- the receiving means 85 amplifies the received signal. For this reason, when an ultrasonic sensor is assembled using the acoustic matching layer having the composite structure as in the second embodiment, a large received signal can be obtained, so that the size of the amplifier circuit can be reduced.
- the received signal of the ultrasonic sensor is called the main signal
- the unnecessary signal generated by the amplifier circuit and the unnecessary signal that enters from the outside are called noise
- the degree of amplification decreases as the larger main signal is obtained.
- noise due to the amplifier circuit means can be reduced. Also, since the ratio of the main signal to external noise increases, it is apparently less affected by noise. These are total This leads to improved measurement accuracy.
- the first wave of the received signal is small and therefore difficult to detect.
- the receiving means 85 detects, for example, points P1 and P2 of the third wave by circuit means using a comparator. Therefore, when the waveform changes with temperature, measurement errors increase. Therefore, when the acoustic matching layers of the ultrasonic sensors A and B are made of an inorganic substance, the acoustic properties of the inorganic substance hardly change with temperature, so that the influence on the waveform is reduced, and the measurement accuracy can be improved. Since the acoustic matching body of the present invention includes a ceramic porous body which is an inorganic substance, waveform deformation due to temperature is suppressed, and contributes to improvement of measurement accuracy.
- the acoustic matching body of the composite form described as the second embodiment uses a dry gel of an inorganic oxide as the second porous body, and uses a mixed solution as a raw material thereof as the first porous body.
- the second porous body is filled into the pores defined by the ceramic matrix of the first porous body and the gaps between the ceramic particles formed in the ceramic matrix. Obtained as a structure.
- the second porous body filled in both the pores and the voids between the ceramic particles exerts an anchor effect, and a high level is formed between the second porous body and the first porous body. A bond strength is obtained.
- the ultrasonic transmitting and receiving apparatus of the present invention when used in particular with a composite acoustic matching layer, it is possible to increase the transmission signal to increase the reception signal, thereby increasing the measurement accuracy.
- the composite acoustic matching layer the second porous body provides good acoustic matching, and the first porous body determines the waveform of the signal received, and determines the specific point (Pl in FIG. 15). , P2) to form a large amplitude signal that is advantageous for measurement. Therefore, the combined acoustic matching layer of the present invention is excellent in both acoustic matching and waveform shaping as a whole.
- the acoustic matching body according to the present invention matches the acoustic impedance between the gas and the vibrator, improves the ultrasonic output of the ultrasonic generator, and propagates the gas. It is possible to improve the reception output of an ultrasonic receiving device that receives ultrasonic waves . Therefore, the acoustic matching body of the present invention provides a commercial or household ultrasonic gas flow rate measuring device (for example, a gas meter) for measuring the flow rates of natural gas and liquefied petroleum gas, and a sound velocity that is high like hydrogen. It is suitable for use in ultrasonic flow rate measuring devices that measure the flow rate of gas that makes it difficult to match the acoustic impedance with the transducer.
- a commercial or household ultrasonic gas flow rate measuring device for example, a gas meter
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Transducers For Ultrasonic Waves (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP04771861.4A EP1662840B1 (en) | 2003-08-22 | 2004-08-19 | Sound matching body, process for producing the same, ultrasonic sensor and ultrasonic wave transmitting/receiving system |
CN2004800241835A CN1839660B (zh) | 2003-08-22 | 2004-08-19 | 音响匹配体及其制造方法以及超声波传感器及超声波收发装置 |
JP2005513292A JP4717634B2 (ja) | 2003-08-22 | 2004-08-19 | 音響整合体およびその製造方法、ならびに超音波センサおよび超音波送受信装置 |
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2003-298451 | 2003-08-22 | ||
JP2003298451 | 2003-08-22 | ||
JP2004025202 | 2004-02-02 | ||
JP2004025203 | 2004-02-02 | ||
JP2004-025202 | 2004-02-02 | ||
JP2004-025203 | 2004-02-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005020631A1 true WO2005020631A1 (ja) | 2005-03-03 |
Family
ID=34222160
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2004/011900 WO2005020631A1 (ja) | 2003-08-22 | 2004-08-19 | 音響整合体およびその製造方法、ならびに超音波センサおよび超音波送受信装置 |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP1662840B1 (ja) |
JP (1) | JP4717634B2 (ja) |
KR (1) | KR20060125686A (ja) |
CN (1) | CN1839660B (ja) |
TW (1) | TWI337655B (ja) |
WO (1) | WO2005020631A1 (ja) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008124957A (ja) * | 2006-11-15 | 2008-05-29 | Aloka Co Ltd | 超音波探触子 |
JP2008167147A (ja) * | 2006-12-28 | 2008-07-17 | Matsushita Electric Ind Co Ltd | 超音波送受波器および超音波流量計 |
JP2008172306A (ja) * | 2007-01-09 | 2008-07-24 | Matsushita Electric Ind Co Ltd | 超音波振動子 |
JP2008193539A (ja) * | 2007-02-07 | 2008-08-21 | Matsushita Electric Ind Co Ltd | 音響整合部材とそれを用いた超音波送受波器と超音波流速流量計 |
JP2008261732A (ja) * | 2007-04-12 | 2008-10-30 | Matsushita Electric Ind Co Ltd | 超音波送受波器とそれを使用した超音流速流量計 |
JP2009218748A (ja) * | 2008-03-07 | 2009-09-24 | Panasonic Corp | 音響整合体、超音波送受波器および超音波流量計 |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102012000275A1 (de) * | 2012-01-10 | 2013-07-11 | Nicolay Verwaltung Gmbh | Schallwandler, insbesondere Ultraschallwandler, und Verfahren zu dessen Herstellung |
CN102795816B (zh) * | 2012-07-26 | 2014-04-23 | 中国海洋石油总公司 | 一种声学岩石及其制造方法 |
CN106332448B (zh) * | 2016-08-06 | 2019-04-12 | 业成科技(成都)有限公司 | 超声波传感器及具有该超声波传感器的电子装置 |
CN112763052B (zh) * | 2020-12-16 | 2022-04-08 | 华中科技大学 | 一种反电子监测的宽带声波传感器 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02177799A (ja) * | 1988-09-29 | 1990-07-10 | British Gas Plc | 整合部材及びその形成方法 |
JP2001346294A (ja) * | 2000-06-01 | 2001-12-14 | Matsushita Electric Ind Co Ltd | 音響整合部材 |
JP2002051398A (ja) * | 2000-08-04 | 2002-02-15 | Matsushita Electric Ind Co Ltd | 音響整合部材およびその製造方法 |
WO2003064981A1 (fr) * | 2002-01-28 | 2003-08-07 | Matsushita Electric Industrial Co., Ltd. | Couche d'adaptation acoustique, emetteur/recepteur ultrasonore, et debitmetre ultrasonore |
JP2003333693A (ja) * | 2002-05-16 | 2003-11-21 | Olympus Optical Co Ltd | 超音波振動子及びその製造方法 |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ATE548860T1 (de) * | 1999-11-12 | 2012-03-15 | Panasonic Corp | Akustischer anpassungs werkstoff,verfahren zur herstellung desselben und ultraschallübertrager mit diesem wekstoff |
JP3611796B2 (ja) * | 2001-02-28 | 2005-01-19 | 松下電器産業株式会社 | 超音波送受波器、超音波送受波器の製造方法及び超音波流量計 |
JP2003125493A (ja) * | 2001-10-11 | 2003-04-25 | Matsushita Electric Ind Co Ltd | 音響整合部材およびその製造方法 |
JP3633926B2 (ja) * | 2002-01-28 | 2005-03-30 | 松下電器産業株式会社 | 超音波送受信器および超音波流量計 |
JP2003318541A (ja) * | 2002-04-24 | 2003-11-07 | Kyocera Corp | セラミック多層配線基板の製造方法 |
-
2004
- 2004-08-19 JP JP2005513292A patent/JP4717634B2/ja not_active Expired - Fee Related
- 2004-08-19 EP EP04771861.4A patent/EP1662840B1/en not_active Expired - Fee Related
- 2004-08-19 CN CN2004800241835A patent/CN1839660B/zh not_active Expired - Fee Related
- 2004-08-19 WO PCT/JP2004/011900 patent/WO2005020631A1/ja active Application Filing
- 2004-08-19 KR KR1020067003493A patent/KR20060125686A/ko not_active Application Discontinuation
- 2004-08-20 TW TW093125145A patent/TWI337655B/zh not_active IP Right Cessation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02177799A (ja) * | 1988-09-29 | 1990-07-10 | British Gas Plc | 整合部材及びその形成方法 |
JP2001346294A (ja) * | 2000-06-01 | 2001-12-14 | Matsushita Electric Ind Co Ltd | 音響整合部材 |
JP2002051398A (ja) * | 2000-08-04 | 2002-02-15 | Matsushita Electric Ind Co Ltd | 音響整合部材およびその製造方法 |
WO2003064981A1 (fr) * | 2002-01-28 | 2003-08-07 | Matsushita Electric Industrial Co., Ltd. | Couche d'adaptation acoustique, emetteur/recepteur ultrasonore, et debitmetre ultrasonore |
JP2003333693A (ja) * | 2002-05-16 | 2003-11-21 | Olympus Optical Co Ltd | 超音波振動子及びその製造方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP1662840A4 * |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008124957A (ja) * | 2006-11-15 | 2008-05-29 | Aloka Co Ltd | 超音波探触子 |
JP2008167147A (ja) * | 2006-12-28 | 2008-07-17 | Matsushita Electric Ind Co Ltd | 超音波送受波器および超音波流量計 |
JP2008172306A (ja) * | 2007-01-09 | 2008-07-24 | Matsushita Electric Ind Co Ltd | 超音波振動子 |
JP2008193539A (ja) * | 2007-02-07 | 2008-08-21 | Matsushita Electric Ind Co Ltd | 音響整合部材とそれを用いた超音波送受波器と超音波流速流量計 |
JP2008261732A (ja) * | 2007-04-12 | 2008-10-30 | Matsushita Electric Ind Co Ltd | 超音波送受波器とそれを使用した超音流速流量計 |
JP2009218748A (ja) * | 2008-03-07 | 2009-09-24 | Panasonic Corp | 音響整合体、超音波送受波器および超音波流量計 |
Also Published As
Publication number | Publication date |
---|---|
EP1662840A4 (en) | 2008-09-24 |
KR20060125686A (ko) | 2006-12-06 |
CN1839660A (zh) | 2006-09-27 |
TWI337655B (en) | 2011-02-21 |
CN1839660B (zh) | 2011-03-02 |
JP4717634B2 (ja) | 2011-07-06 |
EP1662840B1 (en) | 2014-10-01 |
JPWO2005020631A1 (ja) | 2007-11-01 |
EP1662840A1 (en) | 2006-05-31 |
TW200512434A (en) | 2005-04-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN100536607C (zh) | 声音匹配部件、超声波换能器、超声波流量计及其制造方法 | |
US6989625B2 (en) | Acoustic matching layer, ultrasonic transducer and ultrasonic flowmeter | |
JPH0257099A (ja) | 複合圧電振動子 | |
WO2005020631A1 (ja) | 音響整合体およびその製造方法、ならびに超音波センサおよび超音波送受信装置 | |
Mercadelli et al. | Porous piezoelectric ceramics | |
JP2009105709A (ja) | 超音波送受波器とそれを使用した超音波流れ測定装置 | |
JP2008261732A (ja) | 超音波送受波器とそれを使用した超音流速流量計 | |
JP4014940B2 (ja) | 音響整合部材、超音波送受波器、超音波流量計およびこれらの製造方法 | |
JP2006023099A (ja) | 音響整合層およびそれを用いた超音波送受信器並びにこの超音波送受信器を有する超音波流れ計測装置 | |
JP2008167147A (ja) | 超音波送受波器および超音波流量計 | |
JP2974815B2 (ja) | 超音波振動子及びその製造方法 | |
JP2008160636A (ja) | 音響整合層 | |
JP2005260409A (ja) | 超音波振動子およびその製造方法、超音波流体計測装置 | |
JP4415713B2 (ja) | 音響整合層および流体の流れ計測装置 | |
JP4983282B2 (ja) | 音響整合部材 | |
JP2005241410A (ja) | 超音波振動子およびその音響整合層の製造方法 | |
JP4439710B2 (ja) | 音響整合部材とその製造方法 | |
JP2008288658A (ja) | 音響整合部材とそれを用いた超音波送受波器、超音波流速流量計 | |
JP2008263419A (ja) | 音響整合体、超音波送受波器、および超音波流速流量計 | |
JP2006166183A (ja) | 超音波振動子およびそれを用いた流体の流れ測定装置 | |
CN116813334A (zh) | 多孔无铅压电陶瓷元件、空气耦合多孔无铅超声换能器及其制备方法 | |
JP2005159811A (ja) | 超音波振動子およびその製造方法 | |
JP2008193290A (ja) | 音響整合部材、超音波送受波器、および超音波流量計 | |
JP2008193294A (ja) | 音響整合層および超音波送受波器 | |
JP2008193292A (ja) | 音響整合層とそれを用いた超音波振動子および超音波流速・流量計 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200480024183.5 Country of ref document: CN |
|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2005513292 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2004771861 Country of ref document: EP Ref document number: 1020067003493 Country of ref document: KR |
|
WWP | Wipo information: published in national office |
Ref document number: 2004771861 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 1020067003493 Country of ref document: KR |