JPH11218100A - Ultrasonic wave converging device and ultrasonic wave liquid jetting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve energy convergence efficiency in an acoustic lens by forming the shape of a reflecting surface made of a partial surface of a solid member into a shape that longitudinal wave ultrasonic wave radiated from an ultrasonic wave originating source completely reflects in liquid and converges into a preliminarily stipulated focus of longitudinal wave ultrasonic wave. SOLUTION: An opening surface to be an acoustic radiation surface of an ultrasonic wave originating source 1 is formed into a circular shape, the opening surface is made to come into contact with liquid and ultrasonic wave is radiated in liquid from the ultrasonic wade originating source 1. In liquid, a solid member in which a partial surface is formed into a partial shape of a paraboloid of revolution is arranged and the partial surface of this solid member is formed as a reflecting surface 4 reflecting ultrasonic wave radiated in liquid from the ultrasonic wave originating source 1 in liquid. The shape of this reflecting surface 4 is formed into a shape that longitudinal wave ultrasonic wave radiated from the ultrasonic originating source 1 reflects in liquid and converges into a preliminarily stipulated focus 5. The shape of the reflecting surface 4 is formed into a shape that phase shift amount according to reflection when each sound ray is reflected on the reflecting surface 4 become in-phase via each sound ray.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic converging device for converging an ultrasonic wave to a focal point, and an ultrasonic liquid ejecting device including the ultrasonic converging device and a liquid supply device for supplying a liquid. .

[0002]

2. Description of the Related Art As a conventional ultrasonic convergence apparatus, an apparatus using an acoustic lens as shown in FIG. 18 is known. The ultrasonic focusing apparatus shown in FIG. 18 is cited from “Ultrasonic Technique Handbook”, published by Nikkan Kogyo Shimbun, June 25, 1991, page 171. In FIG. 18, 1 is an ultrasonic wave source, 2 is an acoustic lens, 3 is each sound ray of longitudinal ultrasonic waves, and 5 is a focal point. In the ultrasonic focusing device shown in FIG. 18 using the acoustic lens 2, the opening of the ultrasonic transmitting source 1 is attached to the acoustic lens 2, and each sound of the longitudinal ultrasonic wave generated from the ultrasonic transmitting source 1 is provided. The line 3 propagates through the liquid through the acoustic lens 2 and converges on a focal point 5 in the liquid.

[0003] Other conventional ultrasonic focusing devices are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 60-214111 and 61-51.
As disclosed in JP-A-511-511, JP-A-3-136642, JP-A-3-136463, and JP-A-3-205046, FIG. An ultrasonic focusing device as shown is also known. The ultrasonic focusing apparatus shown in FIG.
In the figure, reference numeral 1 denotes an ultrasonic transmission source having a shape different from that of the ultrasonic convergence device shown in FIG. 18, 3 denotes each sound ray of longitudinal ultrasonic waves, 5 denotes a focus, 4
Is a reflecting surface, and 6 is a conical reflector. In the ultrasonic convergence device shown in FIG. 19, the shape of the reflecting surface 4 is a paraboloid of revolution, and each sound ray 3 of the longitudinal ultrasonic wave generated from the ultrasonic wave transmitting source 1 is once reflected by a conical reflector. After being reflected by 6 and further by reflecting surface 4, it converges on focal point 5 in the liquid.

Other conventional ultrasonic focusing devices are disclosed in, for example, JP-A-2-55139 and JP-A-2-8.
9647, JP-A-2-103152, JP-A-2-164543, JP-A-2-164546, JP-A-2-235644, JP-A-2-23
As disclosed in Japanese Patent No. 8949, there is also known an ultrasonic convergence device as shown in FIG. 20 for converging an ultrasonic wave to a focal point using a reflecting surface. The ultrasonic convergence apparatus shown in FIG. 20 is cited from Japanese Patent Application Laid-Open No. 2-89647. In the figure, 1 is an ultrasonic transmission source, 3 is each sound ray of longitudinal ultrasonic waves, and 5 is a focal point in a liquid. Reference numeral 4 denotes a reflection surface. FIG.
In the ultrasonic convergence device shown in (1), the cross-sectional shape of the reflection surface 4 is a paraboloid, and the cross-sectional shape is uniform in a direction perpendicular to the cross-section. Each sound ray 3 of the longitudinal ultrasonic wave generated from the ultrasonic wave transmission source 1 is reflected by the reflection surface 4 and then converges to a focal point 5.

When each sound ray 3 of longitudinal ultrasonic waves propagates in a liquid and enters a boundary surface with a solid, if the incident angle is smaller than the critical angle related to the longitudinal wave, the liquid moves from the liquid to the solid. , Transmission of longitudinal waves and shear waves occurs. When the incident angle is equal to or larger than the critical angle for longitudinal waves and smaller than the critical angle for transverse waves, transverse waves are transmitted from the liquid to the solid. When the incident angle is equal to or larger than the critical angle with respect to the shear wave, the longitudinal wave and the shear wave do not pass through the solid, and the longitudinal ultrasonic wave completely reflects. In addition,
When a longitudinal ultrasonic wave propagating in a liquid enters a boundary surface with a solid, a critical angle for a transverse wave is generally larger than a critical angle for a longitudinal wave.

As described above, when the longitudinal ultrasonic wave propagates through the liquid and enters the interface with the solid, if the incident angle is smaller than the critical angle for the shear wave, the transmission of the longitudinal wave and the shear wave into the solid is performed. , Or only the transverse wave is transmitted. This means that part of the energy of the longitudinal ultrasonic wave reflected into the liquid is lost, and that the reflection efficiency is poor.

The conventional ultrasonic convergence device shown in FIG. 18 uses the acoustic lens 2 to converge longitudinal ultrasonic waves, and does not use a reflecting surface to converge ultrasonic waves. The purpose of the invention is to converge longitudinal ultrasonic waves, but the structure is completely different.

[0008]

The conventional ultrasonic convergence device and the ultrasonic liquid jetting device using the ultrasonic convergence device are configured as described above, so that the longitudinal ultrasonic wave propagates in the liquid. The above-described consideration and study regarding the incident angle when the light is incident on the reflecting surface 4 is not performed, and the reflecting surface 4 is not formed based on such consideration and study.
For this reason, there is a problem that the reflection efficiency at the reflection surface 4 is poor, and the longitudinal ultrasonic waves radiated from the ultrasonic transmission source 1 cannot be efficiently collected at the focal point 5.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an ultrasonic convergence apparatus capable of efficiently converging longitudinal ultrasonic waves radiated from an ultrasonic transmission source to a focal point, and the ultrasonic convergence apparatus. An object of the present invention is to obtain an ultrasonic liquid ejection device using the device.

[0010]

According to the ultrasonic convergence apparatus of the present invention, the shape of the reflecting surface formed by a part of the surface of the solid member is different from that of the longitudinal ultrasonic wave radiated from the ultrasonic transmission source. In relation to the incident angle of the sound ray, the longitudinal wave ultrasonic wave is completely reflected in the liquid and is configured to converge to a predetermined focal point of the longitudinal wave ultrasonic wave, and each sound ray is reflected. The amount of phase shift accompanying reflection at the time of reflection is the same for each sound ray.

In the ultrasonic focusing apparatus according to the present invention, the unit of length is [m], the density of the liquid, the sound velocity of the longitudinal ultrasonic wave in the liquid, the density of the solid member, the longitudinal wave in the solid member. The coefficient a, which is a value equal to or more than a predetermined value having a unit of [m ^-1 ] determined by the sound speed of the ultrasonic wave and the sound wave of the transverse ultrasonic wave in the solid member, is a, and the diameter of the upper end face of the paraboloid of revolution. Is the length of D, a curve given by a quadratic function defining the cross section of the paraboloid of revolution with the rotation axis as the y axis is orthogonal to the y axis at the origin crossing the y axis. Line is x
A parabola defined by y = (2a / D) × ² , which is an axis, and constituted by a part of the shape of the rotating paraboloid, and each sound ray of the longitudinal ultrasonic wave is A reflection surface having a shape converging to a focal point, and each of the sound rays is reflected at an incident angle at which each of the sound rays is completely reflected, in parallel with the rotation axis of the paraboloid of revolution constituting the reflection surface. And an ultrasonic wave transmission source arranged at a position to radiate to a surface.

An ultrasonic convergence apparatus according to the present invention is characterized in that, in a region where each acoustic ray of a longitudinal ultrasonic wave radiated from an ultrasonic transmission source is completely reflected, the density ρ _{1 of} the liquid, the longitudinal ultrasonic wave in the liquid, of sound velocity [nu _l, the density [rho ₂ of the solid member, the longitudinal wave ultrasonic sound speed [nu _L of the solid member in the phase of the reflectivity defined by transverse ultrasonic wave sound velocity [nu _S of the solid member in the -180 ° The diameter d of the lower end face of the paraboloid of revolution so that the incident angle is limited within the range of not less than 90 ° and the first incident angle θ ′.
And a coefficient a of a parabola defined by y = (2a / D) × ² which determines the shape of the paraboloid of revolution within a range defined by the diameter D of the upper end face.

[0013] In the ultrasonic focusing apparatus according to the present invention, the unit of length is [m], the density of the liquid, the sound velocity of longitudinal ultrasonic waves in the liquid, the density of the solid member, and the vertical length in the solid member. A is a coefficient having a unit of [m ^-1 ] which is a value equal to or more than a predetermined value determined by the sound speed of the wave ultrasonic wave and the sound speed of the transverse wave ultrasonic wave in the solid member. Is the separation distance of D and the symmetry axis of the two paraboloids is the y-axis, a curve given by a quadratic function that defines the cross section of the two paraboloids is at the origin at which the y-axis intersects. A line perpendicular to the y-axis is represented by x = y = (2a / D) x ² ,
A reflection surface that is formed by a part of the paraboloid that is uniform in a direction perpendicular to the cross section and has a shape that converges each sound ray of the longitudinal ultrasonic wave to a focal point of the paraboloid; An ultrasonic transmission source is provided which emits each sound ray at an incident angle that is completely reflected on the reflection surface in parallel with the axis.

In the ultrasonic convergence apparatus according to the present invention, the distance between the upper end surfaces of the two paraboloids is set to D in a region where each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic transmission source is completely reflected.
Y = (2a / determining the shape of the paraboloid when
The coefficient a of the parabola defined by D) x ^2, the incident angle is, the density of the liquid [rho _1, the longitudinal wave ultrasonic sound speed [nu _l in the liquid, the density [rho ₂ of the solid member, the vertical of the solid member in First incident angle θ ′ at which the phase of the reflectance defined by the sound velocity ν _L of the wave ultrasonic wave and the sound velocity ν _S of the transverse ultrasonic wave in the solid member becomes −180 °.
The value is set so as to be limited within the range of 90 ° or less.

In the ultrasonic convergence apparatus according to the present invention, the range of the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave source on the reflecting surface of each sound ray is completely reflected by each sound ray, and The difference is set so that the difference between the phase shift amounts due to the reflection of each sound ray between the sound rays becomes substantially zero.

In the ultrasonic convergence apparatus according to the present invention, the range in which the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave transmitting source to the reflection surface of each sound ray is completely reflected by each sound ray, and This is a range in which the maximum value of the difference between the sound rays in the phase shift amount due to the reflection of each sound ray is approximately 40 ° or less.

In the ultrasonic focusing apparatus according to the present invention, when the liquid is water or ink and the solid member is brass, and the unit of length is [m], the value of the coefficient a is approximately 1.3 × 10 ^3.
[M ^-1 ] or more.

In the ultrasonic focusing apparatus according to the present invention, when the liquid is water or ink and the solid member is zinc, and the unit of length is [m], the value of the coefficient a is approximately 1 × 10 ^3.
[M ^-1 ] or more.

The ultrasonic focusing apparatus according to the present invention has a coefficient a of about 0.8 × when the unit of length is [m] with water or ink as a liquid and magnesium as a solid member.
It is 10 ³ [m ^-1 ] or more.

In the ultrasonic focusing apparatus according to the present invention, when the liquid is water or ink, the solid member is aluminum, and the unit of length is [m], the value of the coefficient a is approximately 0.7 ×
It is 10 ³ [m ^-1 ] or more.

An ultrasonic liquid jetting apparatus according to the present invention comprises an ultrasonic wave transmitting source for emitting longitudinal ultrasonic waves into a liquid, and an incident angle of each sound ray of the longitudinal ultrasonic wave emitted from the ultrasonic transmitting source. In the relationship, the longitudinal wave is completely reflected in the liquid and converges on a predetermined focal point of the longitudinal wave, and the sound rays are reflected by the reflecting surface. An ultrasonic focusing device comprising: a solid member having a reflecting surface disposed in the liquid, the phase shift amount of which is in the same phase with respect to each sound ray due to reflection of the liquid; and a liquid supply for sequentially supplying the liquid The apparatus includes an apparatus and an ejection hole formed near the focal point, where the liquid is ejected by longitudinal ultrasonic waves in the liquid.

In the ultrasonic liquid jetting apparatus according to the present invention, the unit of length is [m], and the density of the liquid, the sound velocity of longitudinal ultrasonic waves in the liquid, the density of the solid member, the density of the solid member, The coefficient a, which is a predetermined value or more having a unit of [m ^-1 ] determined by the sound speed of the longitudinal ultrasonic wave and the sound speed of the transverse ultrasonic wave in the solid member, is a, and the upper end face of the rotating paraboloid shape When the length of the diameter of D is D, a curve given by a quadratic function that defines the cross section of the paraboloid of revolution with the rotation axis as the y-axis is the same as the y-axis at the origin crossing the y-axis. Direct to line a parabola defined by y = (2a / D) x 2 is the x axis, is constituted by a part of the paraboloid shape, the respective sound ray of the longitudinal wave ultrasonic A reflecting surface having a shape converging to the focal point of a paraboloid of revolution, formed of a solid member, and arranged in a liquid A superposition disposed at a position parallel to the rotation axis of the paraboloid of revolution constituting the reflection surface, at an incident angle at which each sound ray is completely reflected, and at a position for emitting each sound ray to the reflection surface. An ultrasonic convergence device having a sound source, a liquid supply device for sequentially supplying the liquid, and an ejection hole configured near the focal point, where the liquid is ejected by longitudinal ultrasonic waves in the liquid. It is prepared for.

The ultrasonic liquid jetting apparatus according to the present invention has a parabola y = (2a / D) x which determines the shape of the paraboloid of revolution within the range defined by the diameter d of the lower end face and the diameter D of the upper end face. ^Two
The coefficient a of the liquid in a region where each sound ray of longitudinal ultrasonic waves radiated from the ultrasonic wave source is completely reflected, the density ρ ₁ of the liquid,
The sound velocity ν _l of longitudinal ultrasonic waves in the liquid, the density ρ of the solid member
_2. The first incident angle θ ′ at which the phase of the reflectance defined by the sound velocity ν _L of the longitudinal ultrasonic wave in the solid member and the sound velocity ν _S of the transverse ultrasonic wave in the solid member becomes −180 ° or more. And 90
値 The value is determined so that the incident angle is restricted within the following range.

In the ultrasonic liquid jetting apparatus according to the present invention, the unit of length is [m], and the density of the liquid, the sound velocity of longitudinal ultrasonic waves in the liquid, the density of the solid member, the density of the solid member, A coefficient having a unit of [m ^-1 ] which is a value equal to or more than a predetermined value determined by the sound speed of the longitudinal ultrasonic wave and the sound speed of the transverse ultrasonic wave in the solid member is a, the upper end of the two paraboloids When the separation distance between the parts is D and the symmetry axis of the two paraboloids is the y-axis, the curve given by a quadratic function defining the cross section of the two paraboloids is the origin at which the y-axis intersects , The line orthogonal to the y-axis is the x-axis, y = (2a / D) x ²
And a reflecting surface having a shape formed by a part of the paraboloid that is uniform in a direction perpendicular to the cross section and converging each sound ray of the longitudinal ultrasonic wave to a focal point of the paraboloid. An ultrasonic wave source arranged at a position to radiate each sound ray to the reflection surface at an incident angle at which each sound ray is completely reflected in parallel with the symmetry axis of the paraboloid constituting the reflection surface; An ultrasonic convergence device having the following.

In the ultrasonic liquid jetting apparatus according to the present invention, in the region where each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic wave transmitting source is completely reflected, the shape of two paraboloids is determined.
(2a / D) × ² , a parabolic coefficient defined by x2, the incident angle being the density ρ _{1 of} the liquid, the sound velocity ν _l of longitudinal ultrasonic waves in the liquid, the density ρ _{2 of} the solid member, and the solid member The sound velocity ν _L of the longitudinal ultrasonic wave inside, the sound velocity ν _S of the transverse ultrasonic wave inside the solid member
Is greater than or equal to the first angle of incidence θ ′ at which the phase of the reflectance specified by (−180) is −180 °, and is limited to a value within the range of 90 ° or less.

The ultrasonic liquid jetting device according to the present invention is characterized in that the range of the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave source in the ultrasonic focusing device to the reflecting surface of each sound ray is determined by the above-mentioned sound ray. Are completely reflected, and the difference between the sound rays in the amount of phase shift caused by the reflection of each sound ray is set to a range in which the difference is substantially zero.

The ultrasonic liquid ejecting apparatus according to the present invention is characterized in that the range in which the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave source in the ultrasonic convergence device to the reflection surface of each sound ray is taken by each of the above-mentioned sounds. The line is completely reflected, and the maximum value of the difference in the amount of phase shift caused by the reflection of each sound ray is in a range of about 40 ° or less.

In the ultrasonic liquid jetting device according to the present invention, the reflecting surface of the ultrasonic converging device is constituted by a solid member made of brass, is arranged in a liquid such as water or ink, and has a unit of length [m]. When the value of the coefficient a is approximately 1.3,
× 10 ³ [m ^-1 ] or more.

In the ultrasonic liquid jetting device according to the present invention, the reflecting surface of the ultrasonic focusing device is constituted by a solid member made of zinc, arranged in a liquid such as water or ink, and the unit of length is [m]. When the value of the coefficient a is approximately 1 × 1
0 ³ [m ^-1 ] or more.

In the ultrasonic liquid jetting device according to the present invention, the reflecting surface of the ultrasonic focusing device is constituted by a solid member made of magnesium, is arranged in a liquid such as water or ink, and has a unit of length [m]. In this case, the value of the coefficient a is set to be about 0.8 × 10 ³ [m ⁻¹ ] or more.

In the ultrasonic liquid jetting device according to the present invention, the reflecting surface of the ultrasonic converging device is constituted by a solid member made of aluminum, arranged in a liquid such as water or ink, and the unit of length is [m]. The value of the coefficient a is set to be about 0.7 × 10 ³ [m ⁻¹ ] or more.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a schematic diagram showing the configuration of the ultrasonic convergence device according to the first embodiment, and FIG. 2 is a cross-sectional view including the x-axis and the y-axis shown in FIG. In FIG. 1, reference numeral 1 denotes an ultrasonic transmission source. The aperture surface that is the acoustic radiation surface of the ultrasonic wave source 1 is formed in a circular shape. The opening surface of the ultrasonic transmission source 1 is in contact with the liquid, and the ultrasonic transmission source 1 emits ultrasonic waves into the liquid. In the liquid, a solid member having a part of the surface having the shape of a part of the paraboloid of revolution is arranged. A part of the surface of the solid member is an ultrasonic transmission source 1
It is used as a reflection surface of an ultrasonic wave for reflecting the ultrasonic wave radiated into the liquid from the liquid. In FIG. 1, the solid member is not shown for the sake of simplicity, and reference numeral 4 is assigned to an ultrasonic reflection surface which is a part of the surface of the solid member, and only the reflection surface 4 is illustrated. Is shown. The same applies to FIG.

In FIG. 1, the y-axis corresponds to the rotation axis of the paraboloid of revolution. The ultrasonic transmission source 1 is arranged so that the y-axis is orthogonal to the opening surface of the ultrasonic transmission source 1. further,
The ultrasonic transmission source 1 and the ultrasonic reflection surface 4 are relatively arranged so that the y-axis passes through the center of the opening surface of the ultrasonic transmission source 1.

In FIG. 2, the origin of the coordinates is set at a point where a parabola which is a cross section of the paraboloid of revolution intersects the y-axis.
Further, the coordinate axes orthogonal to the y axis in the cross section are set as the x axis and the z axis. The way of using these coordinate axes is the same in FIG. If the unit of length is represented by [m], the cross-sectional shape of the reflecting surface 4 is represented as y = a′x ² using the coefficient a ′. Here, the unit of the coefficient a 'is [m ^-1 ].

In FIG. 1, the lower end of the reflection surface 4 is denoted by reference numeral 41, and the upper end thereof is denoted by reference numeral 42. The diameter of the lower end portion 41 is the diameter of the opening surface of the ultrasonic wave transmitting source 1 as D.
Then, it is set to D or less. Further, the diameter of the upper end portion 42 may be larger or smaller than the diameter D of the opening surface of the ultrasonic wave transmission source 1 or may be the same. However, if the diameter of the upper end portion 42 is equal to or larger than the diameter D of the opening surface of the ultrasonic transmission source 1, all of the energy of the ultrasonic waves radiated from the ultrasonic transmission source 1 can be used, so that the energy use efficiency is reduced. There is an advantage that can be raised.

FIG. 1 shows a case where the upper end portion 42 of the ultrasonic wave reflecting surface 4 and the opening surface of the ultrasonic wave transmitting source 1 are spatially separated, but this separation distance is zero. Alternatively, the positional relationship may be such that the upper end portion 42 is located above the opening surface of the ultrasonic wave transmission source 1.

Next, the operation of the ultrasonic focusing apparatus shown in FIGS. 1 and 2 will be described with reference to FIG. In FIG. 2, a line indicated by a reference numeral 3 and an arrow indicates a sound ray of the ultrasonic wave emitted from the ultrasonic wave transmission source 1, and a direction of the arrow indicates a propagation direction of the ultrasonic wave. Points indicated by reference numeral 5 indicate focal points of longitudinal ultrasonic waves emitted from the ultrasonic wave source 1 into the liquid.

Each sound ray 3 of the longitudinal ultrasonic wave radiated into the liquid from the ultrasonic wave source 1 travels in the liquid along the y-axis and enters the reflecting surface 4. Each sound ray 3 reflected by the reflecting surface 4 travels through the liquid to the focal point 5. Since the shape of the reflecting surface 4 is a part of the shape of the paraboloid of revolution, the distance that each sound ray 3 propagates from the ultrasonic wave source 1 to the focal point 5 is constant regardless of the sound ray 3.

In the ultrasonic convergence apparatus of the present invention, the shape of the ultrasonic reflecting surface 4 is determined based on the characteristics related to the ultrasonic waves of the liquid and the elastic characteristics of the solid member described above. This is a point different from the conventional one. Next, this point will be described in detail with reference to FIGS.

FIG. 3 is an operation explanatory diagram showing a state of reflection and transmission when longitudinal ultrasonic waves are incident from the liquid side, with the upper half in the figure being liquid and the lower half being solid. In FIG. 3, 3
Denotes a sound ray in the liquid, and 7 denotes a boundary surface between the liquid and the solid. 3
The sound rays 1 and 32 are also sound rays, but are newly added to distinguish them from the sound ray 3 in the liquid, 31 is a sound ray of a longitudinal wave transmitted through a solid, and 32 is a sound ray in a solid. This is the sound ray of the transmitted transverse wave. θ is the angle of incidence.

FIG. 3 shows a case where the incident angle θ is smaller than the critical angle for the longitudinal wave, and the transmission of the longitudinal wave and the transverse wave occurs in the solid. Let the density in the liquid be ρ
Represents _1, represents the longitudinal speed of sound in the liquid at [nu _l represents a density in said solid [rho _2, the longitudinal speed of sound in said solid represented by [nu _L, the shear wave velocity in said solid [nu _S And the reflectance of longitudinal ultrasonic waves into the liquid is represented by R, the reflectance R is

[0042]

(Equation 1)

## EQU1 ## When the incident angle θ is equal to or larger than the critical angle for the longitudinal wave and smaller than the critical angle for the shear wave, only the shear wave is transmitted into the solid. At this time, the reflectance R of the longitudinal ultrasonic wave into the liquid is

[0044]

(Equation 2)

## EQU2 ## In the above equation (2), j
Is an imaginary unit. When the incident angle θ is equal to or larger than the critical angle for the shear wave, the longitudinal wave and the shear wave do not penetrate into the solid, and the longitudinal ultrasonic wave completely reflects. At this time, the reflectance R of the longitudinal ultrasonic wave into the liquid is

[0046]

(Equation 3)

## EQU5 ## Formula (1), Formula (2),
Equation (3) is an equation determined by Snell's law of reflection and refraction. When a longitudinal ultrasonic wave propagating in a liquid enters a boundary surface with a solid, a critical angle for a transverse wave is generally larger than a critical angle for a longitudinal wave.

As described above, when the longitudinal wave ultrasonic wave propagates in the liquid and enters the boundary surface with the solid, if the incident angle θ is smaller than the critical angle for the transverse wave, the longitudinal wave and the The transmission of the shear wave or the transmission of only the shear wave occurs.
This means that part of the energy of the longitudinal ultrasonic wave reflected into the liquid is lost, which means that the reflection efficiency is poor.

Further, when the incident angle θ becomes equal to or larger than the critical angle for the transverse wave, the longitudinal wave ultrasonic wave is completely reflected in the liquid as described above, but a phase shift occurs at the time of reflection as described later.

Next, in the case of some combinations of a liquid and a solid, the above-described reflection will be described with specific examples.

FIGS. 4 (a) and 4 (b) show the absolute value, the phase shift amount, and the reflectivity of the case where the liquid is water and the solid is brass when the longitudinal ultrasonic wave is incident from the water side. FIG. 9 is a characteristic diagram in which a relationship with an incident angle is graphed. In FIG. 4A, the vertical axis represents the absolute value (amplitude) of the reflectance, and the horizontal axis represents the incident angle θ. In FIG. 4B, the vertical axis represents the phase of the reflectance, and the horizontal axis represents the incident angle θ. The characteristics of these reflectances are as follows: the density of water is 1 × 10 ³ [Kg / m ³ ]; the longitudinal velocity of ultrasonic waves in water is 1500 [m / s]; and the density of brass is 8.6 × 1.
0 ³ [Kg / m ³ ], the longitudinal sound speed of ultrasonic waves in brass is 47
00 [m / s], the transverse sound speed of ultrasonic waves in brass is 2100
[M / s] is obtained by calculation based on the above equations (1), (2) and (3) determined by Snell's law of reflection and refraction.

In the characteristic diagrams shown in FIGS. 4A and 4B, the critical angle for the longitudinal wave is about 19 °, and in the region where the incident angle θ is smaller than this angle, the longitudinal wave and the transverse wave are solid. Since the light is transmitted to the inside, the absolute value of the reflectance is smaller than 1 as shown in FIG. In the characteristic diagrams shown in FIGS. 4A and 4B, the critical angle for the shear wave is about 45 °, and the incident angle θ is about 19 ° to about 45 °.
In the region of °, since the transverse wave penetrates into the solid, the absolute value of the reflectance is smaller than 1 as shown in FIG. In the region where the incident angle θ is about 45 ° or more, the absolute value of the reflectance is 1 as shown in FIG.
Becomes This means that complete reflection occurs. As shown in FIG. 4B, the phase shift amount of the reflectance is zero when the incident angle θ is about 19 ° or less, which is the critical angle of the longitudinal wave. However, the value is other than zero when the incident angle θ is around 21 °. In particular, in the region where the incident angle θ is about 45 ° or more, as shown in FIG.
Has greatly changed.

The characteristic diagrams shown in FIGS. 5A and 5B show the reflectances obtained in the same manner as in FIGS. 4A and 4B when the liquid is water and the solid is zinc, respectively. It shows the relationship between the absolute value, the amount of phase shift, and the angle of incidence. The characteristic of these reflectances is that the density of water is 1 × 10 ³ [Kg / m
³ ], the longitudinal velocity of the ultrasonic waves in the water is 1500 [m / s],
The density of zinc is 7.2 × 10 ³ [Kg / m ³ ], the longitudinal velocity of ultrasonic waves in zinc is 4210 [m / s], and the lateral velocity of ultrasonic waves in zinc is 2440 [m / s]. I asked. The critical angle for the longitudinal wave in this case is about 21 °, the critical angle for the shear wave is about 38 °, and the incident angle θ of the reflectance
Can be said to be the same as in the case of FIGS. 4A and 4B. In particular, perfect reflection occurs in a region where the incident angle θ is about 38 ° or more, but the phase of the reflectance greatly changes depending on the incident angle.

The characteristic diagrams shown in FIGS. 6A and 6B show the case where the liquid is water and the solid is magnesium, respectively.
5 shows the relationship between the absolute value of the reflectance, the amount of phase shift, and the angle of incidence obtained in the same manner as in (a) and (b) of FIG.
The characteristic of these reflectances is that the density of water is 1 × 10 ³ [Kg
/ M ³ ], and the longitudinal velocity of ultrasonic ultrasonic waves in water is 1500 [m /
s] and the density of magnesium is 1.5 × 10 ³ [Kg
/ M ³ ], the longitudinal velocity of ultrasonic waves in magnesium is 577.
0 [m / s], the transverse sound speed of ultrasonic waves in magnesium is 3
050 [m / s]. The critical angle for longitudinal waves in this case is about 15 °, and the critical angle for shear waves is about 30 °.

The characteristic diagrams shown in FIGS. 7A and 7B show the case where the liquid is water and the solid is aluminum, respectively.
5 shows the relationship between the absolute value of the reflectance, the amount of phase shift, and the angle of incidence obtained in the same manner as in (a) and (b) of FIG.
The characteristic of these reflectances is that the density of water is 1 × 10 ³ [Kg
/ M ³ ], and the longitudinal velocity of ultrasonic ultrasonic waves in water is 1500 [m /
s], and the density of aluminum is 2.7 × 10 ³ [Kg / m
³ ], the longitudinal velocity of ultrasonic waves in aluminum is 6420
[M / s], the transverse speed of ultrasonic waves in aluminum is 30
It was determined as 40 m / s. In this case, the critical angle for the longitudinal wave is about 14 °, and the critical angle for the transverse wave is about 3 °.
0 °.

In FIGS. 6A and 6B and FIGS. 7A and 7B, the dependence of the reflectance on the incident angle θ is shown in FIGS. 4A and 4B. The same can be said for the case of). In particular, perfect reflection occurs in a region where the incident angle θ is equal to or larger than the critical angle for the transverse wave, but the phase of the reflectance greatly changes depending on the incident angle θ. Note that the phase of the reflectance R is φ. That is, the reflectance R is | R | ∠
φ, and | R | is the absolute value of the reflectance R. The phase φ is obtained from the above equation (3).

[0057]

(Equation 4)

Is given by In the characteristic diagrams shown in FIGS. 4 to 7, the liquid is water, but the density of water and ink and the sound speed of longitudinal ultrasonic waves may be considered to be substantially the same. It can be considered that the state of reflection is almost the same.

As described above, the absolute value of the reflectance and the amount of phase shift depend on the density of the liquid, the sound velocity of longitudinal ultrasonic waves in the liquid,
It is determined depending on the density of the solid, the sound velocity of the longitudinal ultrasonic wave in the solid, the sound velocity of the transverse ultrasonic wave in the solid, and the incident angle θ of the sound ray 3. In particular, complete reflection occurs in a region where the incident angle θ is equal to or larger than the critical angle for the transverse wave, but the phase shift amount of the reflectivity greatly changes depending on the incident angle θ, and is 180 °.
May have changed beyond This is because, in the ultrasonic convergence device shown in FIGS. 1 and 2, the ultrasonic wave reflected by the reflecting surface 4 of the ultrasonic wave is partially affected by the incident angle θ of the sound ray 3 to the reflecting surface 4. This means that the line is reflected in the opposite phase with respect to other sound rays, and if the reflection surface 4 is not formed by paying attention to this, the longitudinal wave ultrasonic wave radiated from the ultrasonic wave source 1 This means that the focus 5 is not efficiently gathered.

The ultrasonic focusing apparatus according to the present invention is different from the conventional one in that the shape of the reflecting surface 4 is determined in consideration of the dependence of the reflectance on the incident angle θ as shown in FIGS. Is different. In more detail, the reflecting surface 4 is a part of the paraboloid of revolution, but if the paraboloid of revolution is used as the reflecting surface 4 of ultrasonic waves over the entire surface, Since there is a region on the rotating paraboloid where the phase of the ultrasonic wave that is reflected at each point of the paraboloid and reaches the focal point 5 arrives in an opposite phase, there is a region in which the region is deleted so as to have a shape. A part of the paraboloid of revolution is cut out and used as the reflection surface 4. Thereby, all the ultrasonic waves radiated from the ultrasonic wave source 1 and reflected by the reflection surface 4 and reaching the focal point 5 can reach the same phase, so that the convergence efficiency of the ultrasonic energy to the focal point 5 is improved.

Next, a method for determining the shape of the reflecting surface 4 will be specifically described. In FIG. 1, the diameter of the lower end 41 of the reflection surface 4 is represented by d. The diameter of the upper end of the reflecting surface 4 (the diameter of the opening surface of the ultrasonic transmission source 1) is D. Although the reflecting surface 4 is a part of the paraboloid of revolution, in the cross-sectional shape shown in FIG. D / 2 which is the length
The parabola corresponding to the paraboloid of revolution is defined as y /
(D / 2) = a {x / (D / 2)} ² . In other words, expressed by y = (2a / D) x 2. Here, the unit of the coefficient a is [m ^-1 ].

First, the coefficient a which determines the cross-sectional shape of the paraboloid of revolution, in which all sound rays 3 of longitudinal ultrasonic waves radiated from the ultrasonic wave source 1 and reflected by the reflecting surface 4 reach the focal point 5 in phase. The determination method will be described.

In FIG. 1, the range of the incident angle θ when the sound ray 3 emitted from the ultrasonic wave source 1 is incident on the reflecting surface 4 will be obtained. The slope of the parabola, ie, y ′ =
Considering that dy / dx is 4ax / D, and from geometrical considerations, the range of the incident angle θ is as follows:

[0064]

(Equation 5)

Is obtained. As can be seen in the reflectance characteristics in the case where the liquid is water or ink and the solid is brass, zinc, magnesium and aluminum as shown in FIGS. 4 to 7, the phase shift amount of the reflectance depends on the incident angle θ. In an area that is equal to or greater than the critical angle of the shear wave, that is, in an area where the longitudinal ultrasonic wave incident from the liquid is completely reflected into the liquid, there is an incident angle at which the phase of the reflectance becomes −180 °. Assuming that this incident angle is θ ′, θ ′ is equal to the incident angle θ at which the imaginary part in equation (3) becomes zero. Because, when the imaginary part is zero in the equation (3), the reflectance R =
This is because it becomes -1. In Equation (3), the incident angle θ ′ at which the imaginary part becomes zero is

[0066]

(Equation 6)

Is obtained by When the incident angle θ is 9
When the angle is 0 °, the phase of the reflectance is −18 according to the equation (3).
0 °. Also, the incident angle θ is

[0068]

(Equation 7)

In the region represented by the following expression, the phase of the reflectance is 0 ° or less. Because, in the equation (3), the fact that the phase of the reflectance becomes 0 ° means that the reflectance R = 1. When the reflectance R is 1, it means that the imaginary part in the equation (3) becomes zero. However, the reflectance R when the imaginary part becomes zero in the equation (3) is -1. In equation (3), the reflectance R
It cannot be mathematically possible that 1 becomes 1. Therefore,
In equation (3), the minimum value of the incident angle θ, tan ⁻¹ (2
ad / D) is not less than 90 ° and not less than θ ′ that satisfies the expression (6).

[0070]

(Equation 8)

If the coefficient a for determining the cross-sectional shape of the paraboloid of revolution is determined so as to satisfy the following condition, the ultrasonic wave radiated from the ultrasonic wave source 1 and reflected by the reflecting surface 4 to reach the focal point 5 is:
Since it is possible to reach the focal point 5 with an amount of phase shift in the range of -180 ° to 0 °, that is, it is possible to reach the focal point 5 in the same phase, the convergence efficiency of the ultrasonic energy to the focal point 5 is improved. It should be noted that in the equation (8), the angle of incidence θ of 90 ° or more cannot be physically realized because the shape of the reflection surface 4 is formed by a part of the paraboloid of revolution. However, it is possible that the incident angle θ approaches 90 °.

As described above, each sound ray 3 of the longitudinal ultrasonic wave radiated from the ultrasonic wave source 1 and reflected by the reflection surface 4 to reach the focal point 5
However, the method of determining the coefficient a for determining the cross-sectional shape of the paraboloid of revolution so as to reach the focal point 5 in the same phase has been described. Next, each sound ray 3 of the longitudinal ultrasonic wave radiated from the ultrasonic wave source 1 and reflected by the reflection surface 4 and reaching the focal point 5 is rotated and released so as to reach the focal point 5 with almost the same phase shift amount. A method for determining the coefficient a for determining the cross-sectional shape of the object surface will be described with an example. In this case, the diameter d of the lower end 41 of the reflection surface 4 is
It is set to half the diameter D of the upper end portion 42 of the reflection surface 4.

It is assumed that the number of sound rays 3 radiated from the ultrasonic wave source 1 is M, and the amplitude of each sound ray 3 is 1 / M. The reflectance on the reflection surface 4 is represented by R. Where the reflectance R
Is generally a complex number, as shown in FIGS. The reflectance R is the angle of incidence θ of each sound ray 3 on the reflecting surface 4.
, And take different values, and the attenuation in the liquid is negligible. At this time, if the complex amplitude of each sound ray 3 at the focal point 5 is represented by um (m = 1 to M), the complex amplitude um = R / M. Therefore, when the amplitude obtained at the focal point 5 is represented by | u |

[0074]

(Equation 9)

Is obtained. In this specification, the expression “amplitude” indicates the absolute value of the complex amplitude, and the expression “complex amplitude” indicates the complex value.

Using the liquid (water or ink) and the solid member constituting the reflection surface 4 as brass, using the above equation (9), taking the number M of the sound ray 3 to be sufficiently large, and obtaining the amplitude | u | FIG. 8 shows the calculated result. The reflection surface 4
The diameter of the lower end 41 of the ultrasonic transmission source 1 is as described above.
The diameter D of the opening surface was set to half. The diameter of the upper end portion 42 of the reflection surface 4 is equal to or larger than the diameter D of the opening surface of the ultrasonic wave transmission source 1. If the diameter of the upper end portion 42 is D or more, the calculation result is the same as FIG. The same material constants as those described above for the ultrasonic or elastic properties of water and brass were used.

FIG. 8 shows that the coefficient a is about 1.3 × 10 ^3.
If it is [m ^-1 ] or more, the amplitude | u | is almost 1. This means that each sound ray 3 is completely reflected on the reflecting surface 4,
This means that the phase shift amount due to the reflection at that time has substantially the same value for all the sound rays 3. In addition,
Here, the phase shift amount is the reflectance R shown in the above equation (4).
Represents φ, which is the phase of

When the coefficient a is 1.3 × 10 ³ [m ^-1 ], the range of the incident angle θ is approximately 52 ° from the above equation (5).
About 69 °. When the incident angle θ is within this range, the maximum value of the difference between the sound rays of the phase shift amount φ due to the reflection of each sound ray obtained by the above equation (4) is approximately 40 °. As the coefficient a becomes larger than 1.3 × 10 ³ [m ⁻¹ ], the range of the incident angle θ becomes smaller. Accordingly, the difference between the sound rays in the phase change amount φ due to the reflection of each sound ray is also small.

In the ultrasonic focusing apparatus according to the first embodiment,
A coefficient a for determining the shape of the parabola is set in the range. As a result, the amount of phase shift at the time of reflection by the reflecting surface 4 becomes substantially the same at all points on the reflecting surface 4, so that the efficiency of energy convergence to the focal point 5 can be increased.
In particular, as the coefficient a becomes larger than 1.3 × 10 ³ [m ⁻¹ ], the range of the incident angle θ becomes smaller,
Since the difference between the sound rays in the phase change amount φ due to the reflection of each sound ray is further reduced, the energy convergence efficiency to the focal point 5 can be further increased.

FIG. 9 shows the amplitude | u | obtained at the focal point 5 obtained in the same manner as in FIG. 8 when the liquid is water or ink and the solid member is zinc. The same material constants as those described above for the ultrasonic or elastic properties of water or ink and zinc were used. If the coefficient a is about 1 × 10 ³ [m ⁻¹ ] or more, the amplitude | u
| Is almost 1. Note that the coefficient a is 1.0
In the case of × 10 ³ [m ^-1 ], the range of the incident angle θ is approximately 45 ° to approximately 63 ° from the above formula (5). When the incident angle θ is in this range, the maximum value of the difference between the sound rays of the phase change amount φ due to the reflection of each sound ray obtained by the above equation (4) is approximately 28.
°.

FIG. 10 shows the amplitude | u | obtained at the focal point 5 obtained in the same manner as in FIG. 8 when the liquid is water or ink and the solid member is magnesium.
The same material constants as those described above for the ultrasonic or elastic properties of water or ink and magnesium were used. The coefficient a is about 0.8 × 10 ³ [m ^-1 ]
Above, the amplitude | u | is almost 1. When the coefficient a is 0.8 × 10 ³ [m ⁻¹ ], the range of the incident angle θ is approximately 39 ° to approximately 58 ° according to the expression (5).
It is. When the incident angle θ is within this range, the above equation (4)
The maximum value of the difference between the sound rays in the amount of phase change φ due to the reflection of each sound ray, which is obtained by the above, is approximately 18 °.

FIG. 11 shows the amplitude | u | obtained at the focal point 5 obtained in the same manner as in FIG. 8 when the liquid is water or ink and the solid member is aluminum.
The same material constants as those described above for the ultrasonic or elastic properties of water or ink and aluminum were used. The coefficient a is about 0.7 × 10 ³ [m ^-1 ]
Above, the amplitude | u | is almost 1. When the coefficient a is 0.7 × 10 ³ [m ⁻¹ ], the range of the incident angle θ is approximately 35 ° to approximately 55 ° from the above equation (5).
It is. When the incident angle θ is within this range, the above equation (4)
The maximum value of the difference between the sound rays in the amount of phase change φ due to the reflection of each sound ray, which is obtained by the above, is approximately 32 °.

As can be seen from the above examples,
The coefficient a is determined so that the maximum value of the difference between the sound rays of the phase change amount φ due to the reflection of each sound ray obtained by the above equation (4) becomes approximately 40 ° or less, and the above equation (5) Is set, the amplitude | u | at the focal point obtained by the above equation (9) becomes approximately 1. Further, in the first embodiment, unlike the related art, not only the amplitude (absolute value) of the reflectance on the reflection surface 4 but also the phase is taken into consideration, and each sound ray 3 generated from the ultrasonic transmission source 1 is reflected. Face 4
The shape of the reflecting surface 4 is changed to tan ^-1 (2ad / D) which is the minimum value of the incident angle so that the light is completely reflected on the upper side, and the value of the phase change accompanying the reflection at that time becomes the same phase for all the sound rays 3. ) Is equal to or more than the incident angle θ ′ that satisfies the expression (6). As a result, an operation and effect can be obtained in which the ultrasonic energy generated by the ultrasonic transmission source 1 can be converged on the focal point 5 with higher energy efficiency as compared with the related art.

The coefficient a for determining the shape of the reflecting surface 4
To each sound ray 3 of the longitudinal ultrasonic wave generated from the ultrasonic transmission source 1.
Is completely reflected on the reflecting surface 4 and the amount of phase change due to the reflection at that time is determined to be substantially the same for all the sound rays 3, so that the convergence efficiency of the ultrasonic energy converging to the focal point 5 is improved. Possible effects can be obtained.

In the above description, the case where the solid member forming the reflection surface 4 is disposed in the liquid has been described.
The entirety of the solid member does not need to be immersed in the liquid, and the first embodiment is directed to a longitudinal ultrasonic wave radiated from the ultrasonic wave source 1, reflected by the reflecting surface 4, and reaching the focal point 5. Needless to say, the present invention can also be applied to a case where only the required propagation path is filled with the liquid.

As described above, according to the first embodiment, not only the amplitude (absolute value) of the reflectance on the reflecting surface 4 but also the phase is taken into consideration, and each sound ray 3 generated from the ultrasonic wave transmission source 1 is taken into account. Is completely reflected on the reflecting surface 4, and the shape of the reflecting surface 4 is configured so that the value of the phase change accompanying the reflection at that time is in the same phase with respect to all the sound rays 3. Focused ultrasonic energy with high energy efficiency 5
Thus, there is an effect that an ultrasonic convergence device capable of converging the laser beam is obtained.

The coefficient a for determining the shape of the reflecting surface 4 is given by
Since the phase shift amount when each sound ray 3 of the longitudinal ultrasonic wave generated from the ultrasonic wave transmission source 1 is completely reflected on the reflecting surface 4 is determined so as to be almost the same value for all the sound rays 3, There is an effect that an ultrasonic convergence device capable of improving the convergence efficiency of the ultrasonic energy converging to the focal point 5 is obtained.

Embodiment 2 FIG. 12 is a schematic diagram showing the configuration of the ultrasonic convergence device according to the second embodiment.
FIG. 13 is a sectional view of a section perpendicular to the z-axis shown in FIG. In the ultrasonic convergence device of this embodiment, the aperture surface, which is the acoustic radiation surface of the ultrasonic wave source, is rectangular, and the reflection surface is not a paraboloid of revolution, but a paraboloid that is uniform along a certain direction. The focal point of the longitudinal ultrasonic wave emitted into the liquid from the ultrasonic wave source is formed linearly.

In FIG. 12, reference numeral 5 denotes a linearly formed focal point of longitudinal ultrasonic waves radiated into the liquid. Reference numeral 11 denotes an ultrasonic wave source, and an opening surface, which is an acoustic radiation surface, is formed in a rectangular shape. In addition, the opening surface of the ultrasonic transmission source 11 is in contact with the liquid, and the ultrasonic transmission source 11 emits ultrasonic waves into the liquid. In the liquid, there is disposed a solid member having a part of a surface having a shape of a part of a uniform paraboloid along a certain direction. A part of the surface of the solid member is used as an ultrasonic reflecting surface for reflecting the ultrasonic waves emitted from the ultrasonic wave source 11 into the liquid in the liquid. In FIG. 12, the solid member is not shown for the sake of simplicity, and reference numeral 14 is assigned to the ultrasonic reflection surface which is a part of the surface of the solid member, and only this reflection surface 14 is shown. ing. 41a is the lower end of the reflection surface 14, 42
a is the upper end of the reflection surface 14. The same applies to FIG. 13, and the same or corresponding parts as in FIG. 12 are denoted by the same reference numerals and description thereof is omitted. In FIG.
The line indicated by the reference numeral 3 and an arrow indicates a sound ray of the ultrasonic wave radiated from the ultrasonic wave source 11, and the direction of the arrow indicates the propagation direction of the ultrasonic wave.

In FIG. 12, the y-axis corresponds to the central axis of a parabola which is a cross section of the paraboloid. The z-axis is set in a direction in which the paraboloid has a uniform shape. The x-axis is set in a direction perpendicular to the z-axis and the y-axis. y
The ultrasonic transmission source 11 is arranged so that the axis is orthogonal to the opening surface of the ultrasonic transmission source 11. Further, the ultrasonic transmission source 11 and the ultrasonic reflection surface 14 are relatively arranged so that the y-axis passes through the center point of the opening surface of the ultrasonic transmission source 11.
Further, the ultrasonic transmission source 11 and the reflection surface 14 are relatively arranged so that each side of the rectangle which is the shape of the opening surface of the ultrasonic transmission source 11 is parallel to the x-axis and the z-axis.

In FIG. 12, the origin of the coordinates is taken at the point where the parabola, which is a cross section of the paraboloid, intersects the y-axis. If the unit of length is represented by [m], the cross-sectional shape of the reflection surface 14 is represented as y = a′x ² using the coefficient a ′. Here, the unit of the coefficient a ′ is [m ⁻¹ ].

In FIG. 12, the lower end of the reflection surface 14 is denoted by reference numeral 41a and the upper end thereof is denoted by reference numeral 42a. The distance between the two lower ends 41a along the x-axis direction is as follows. When the length along the x-axis direction of the opening surface of the ultrasonic wave transmission source 11 is D, the length is D or less. Further, the distance along the x-axis direction between the two upper ends 42a may be larger, smaller, or the same as the length D along the x-axis direction of the opening surface of the ultrasonic wave transmission source 11. I do not care. However,
If the distance along the x-axis direction between the two upper ends 42a is equal to or greater than the length D along the x-axis direction of the opening surface of the ultrasonic transmission source 11, radiation from the ultrasonic transmission source 11 is obtained. There is an advantage that the energy utilization efficiency can be increased because all of the energy of the ultrasonic wave thus obtained can be used.

FIG. 12 shows a case where the upper end portion 42a of the ultrasonic reflecting surface 14 and the opening surface of the ultrasonic wave transmitting source 11 are spatially separated, but this separation distance is zero. The upper end portion 42a may be located above the opening surface of the ultrasonic wave transmission source 11 in FIG.

Next, the operation of the ultrasonic convergence device shown in FIGS. 12 and 13 will be described. In the first embodiment, the reflection surface 4 is a part of the paraboloid of revolution, so the focal point 5 is one point in the space. However, in the second embodiment, the reflection surface 14 Is a shape of a part of a paraboloid uniform along the z-axis direction, so that the ultrasonic waves reflected by the reflecting surface 14 converge linearly along the z-axis. That is, there is a focal point 5 that is continuously distributed linearly along the z-axis. The focal point 5 can be called a focal line in the sense that the ultrasonic wave converges linearly, but is referred to as a focal point here for simplicity.

Each sound ray 3 of the longitudinal ultrasonic wave radiated into the liquid from the ultrasonic wave source 11 travels in the liquid along the y-axis and enters the reflecting surface 14. Each sound ray 3 reflected by the reflecting surface 14 advances in the liquid and converges on the focal point 5. Since the shape of the cross section of the reflection surface 14 perpendicular to the z-axis is a parabola, the distance that each sound ray 3 propagates from the ultrasonic wave source 11 to the focal point 5 is constant regardless of the sound ray.

In the ultrasonic focusing apparatus according to the second embodiment of the present invention, the shape of the ultrasonic reflecting surface 14 is determined based on the characteristics related to the ultrasonic waves of the liquid and the elastic characteristics of the solid member described above. The decision point is different from the conventional one.

In the second embodiment, when the liquid is water or ink and the solid is brass, when the liquid is water or ink and the solid is zinc, when the liquid is water or ink and the solid is magnesium, and In each case where the liquid is water or ink and the solid is aluminum, the dependence of the reflectance on the incident angle θ is the same as that shown in FIGS. 4 to 7, respectively.

That is, in the second embodiment as well as in the first embodiment, the absolute value and phase of the reflectivity are determined by the density of the liquid, the sound velocity of longitudinal ultrasonic waves in the liquid, the density of the solid, and the density of the solid. Is determined depending on the sound speed of the longitudinal ultrasonic wave, the sound speed of the transverse ultrasonic wave in the solid, and the incident angle of the sound ray 3. Especially,
In a region where the incident angle θ is equal to or larger than the critical angle for the shear wave ultrasonic wave, perfect reflection occurs, but the phase of the reflectance is the incident angle θ.
And varies over 180 °. This is because, in the ultrasonic focusing device shown in FIGS. 12 and 13, the ultrasonic wave reflected by the ultrasonic reflecting surface 14 is
Depending on the angle of incidence of the sound ray 3 on the reflecting surface 14, it means that a part of the sound ray 3 is reflected in an opposite phase to the other. Source 11
Means that the longitudinal ultrasonic waves radiated from the laser beam do not efficiently reach the focal point 5.

In the ultrasonic convergence apparatus of the second embodiment,
The point that the shape of the reflecting surface 14 is determined in consideration of the dependency of the reflectance on the incident angle θ as shown in FIGS. More specifically, the cross section of the reflecting surface 14 including the x axis and the y axis is a part of a parabola.
Assuming that the surface of the solid member whose cross section is a parabola is used as an ultrasonic reflecting surface over the entire surface, the area on the surface where the phase of the ultrasonic wave reaching the focal point 5 reaches the opposite phase is reached. Is present, so that a part of the surface is cut out so as to have a shape in which this region is deleted,
This is used as the reflection surface 14. Thereby, all the ultrasonic waves radiated from the ultrasonic wave source 11 and reflected by the reflection surface 14 and reaching the focal point 5 can reach the same phase, so that the efficiency of convergence of the ultrasonic energy to the focal point 5 is improved.

Next, a method for determining the shape of the reflecting surface 14 will be described specifically. In FIG. 12, the case where the distance along the x-axis direction between the two lower ends 41a of the reflection surface 14 is D will be described. The distance along the x-axis direction between the two upper ends 42a is D or more, and the reflecting surface 14 is z
Although the cross section perpendicular to the axis is part of the shape of a parabola, in the cross sectional shape shown in FIG. 13, the coordinates of the x axis and the coordinates of the y axis are hereinafter referred to as x of the aperture plane of the ultrasonic wave transmission source 11. The parabola corresponding to the paraboloid is normalized by D / 2, which is half the length along the axial direction, and y / (D / 2) = a
It is represented by {x / (D / 2)} ² . That is, y = (2a /
D) represented by x ^2. Here, the unit of a is [m ^-1 ].

First, the cross-sectional shape of the parabolic surface is set such that all sound rays 3 of longitudinal ultrasonic waves emitted from the ultrasonic wave source 11 and reflected by the reflection surface 14 reach the focal point 5 in the same phase. A method for determining the coefficient a to be determined will be described.

In FIG. 13, the range of the incident angle θ when the sound ray 3 radiated from the ultrasonic wave transmitting source 11 is incident on the reflecting surface 14 is the same as that described in the description of the first embodiment. Is performed in the second embodiment, it can be seen that the same equation is used. Furthermore, the phase of the reflectivity is such that the incident angle θ is equal to or greater than the critical angle of the transverse ultrasonic wave, that is, in the region where the longitudinal ultrasonic wave in the liquid is completely reflected, the reflectivity phase is -180 °. There is an incident angle θ ′ that satisfies the expression (6). When the incident angle θ is 90 °, the phase of the reflectance is −180 °, and the incident angle θ is θ ′ to
In the region of 90 °, the phase of the reflectance is 0 ° or less. Therefore, the minimum value of the incident angle θ, tan ⁻¹ (2ad
If the coefficient a for determining the cross-sectional shape of the paraboloid is determined so that / D) is equal to or greater than θ ′, the ultrasonic wave radiated from the ultrasonic wave source 11 and reflected by the reflecting surface 14 to reach the focal point 5 Can be made to arrive in phase, so that the efficiency of convergence of the ultrasonic energy to the focal point 5 is improved.

As described above, the cross-sectional shape of the parabolic surface in which all the acoustic rays 3 of the longitudinal ultrasonic wave which are radiated from the ultrasonic wave source 11 and reflected by the reflecting surface 14 and reach the focal point 5 reach the focal point 5 in the same phase. The method of determining the coefficient a to be determined has been described.

Next, the sound rays 3 of the longitudinal ultrasonic waves which are radiated from the ultrasonic wave source 11 and reflected by the reflecting surface 14 and reach the focal point 5 can all reach the focal point 5 with almost the same phase. The method of determining the coefficient a for determining the cross-sectional shape of the paraboloid will be described using an example in the case where the distance d between the two lower ends 41a of the reflection surface 14 is half the distance D between the two upper ends 42a. .

As in the first embodiment, also in the second embodiment, the equation (9) is applied to each section perpendicular to the z-axis.
Is assumed to be M, the number of sound rays radiated from the ultrasonic transmission source 11 is assumed to be M, M is sufficiently large, and the amplitude | u | When the constituent solid members are determined as brass, zinc, magnesium, and aluminum, the same results as in FIGS. Here, the distance d along the x-axis direction between the two lower ends 41a is half of the length D along the x-axis direction of the opening surface of the ultrasonic wave transmission source 11 as described above, and The distance along the x-axis between the two upper ends 42a is D or more. Further, the material constants relating to the ultrasonic or elastic properties of water or ink, brass, zinc, magnesium, and aluminum were as described above.

As shown in FIG. 8, when the liquid is water or ink and the solid is brass, if the coefficient a is set to about 1.3 × 10 ³ [m ^-1 ] or more, the amplitude | u | Becomes almost 1. Note that the maximum value of the difference between the sound rays of the phase shift amount φ due to the reflection of each sound ray obtained by the above equation (4) is:
The values are the same as those described in the first embodiment. This is because, in all cross sections perpendicular to the z-axis, each sound ray 3 is completely reflected on the reflecting surface 14, and the phase shift amount φ accompanying the reflection at this time has substantially the same value for all sound rays. Means that. In the ultrasonic focusing apparatus according to the second embodiment, the coefficient a for determining the shape of the parabola is set in the range. Thereby, the phase shift amount φ at the time of reflection by the reflecting surface 14 becomes substantially the same at all points on the reflecting surface 14, so that the efficiency of energy convergence to the focal point 5 can be increased.

From FIG. 9, when the liquid is water or ink and the solid is zinc, the coefficient a is set to about 1 × 10 ³ [m
^-1 ] or more, the amplitude | u |
become. At this time, the maximum value of the difference between the sound rays of the phase shift amount φ due to the reflection of each sound ray obtained by the above equation (4) is the same as the value described in the first embodiment.

From FIG. 10, when the liquid is water or ink and the solid is magnesium, the coefficient a is set to about 0.8.
When the amplitude | u is set to be not less than × 10 ³ [m ⁻¹ ],
| Is almost 1. At this time, the maximum value of the difference between the sound rays of the phase shift amount φ due to the reflection of each sound ray calculated by the above equation (4) is the same as the value described in the first embodiment. .

Further, from FIG. 11, when the liquid is water or ink and the solid is aluminum, the coefficient a is set to about 0.7.
When the amplitude | u is set to be not less than × 10 ³ [m ⁻¹ ],
| Is almost 1. At this time, the maximum value of the difference between the sound rays of the phase change amount φ due to the reflection of each sound ray obtained by the above equation (4) is the same as the value described in the first embodiment.

As can be seen from the above examples, the phase change φ due to the reflection of each sound ray obtained by the above equation (4)
Is determined by determining the coefficient a so that the maximum value of the difference between the respective sound rays is approximately 40 ° or less by determining the coefficient a. ), The amplitude | u | at the focal point 5 becomes substantially 1.

As described above, according to the second embodiment, in all the sections perpendicular to the z-axis, the reflection surface 14
In consideration of not only the amplitude (absolute value) of the reflectance at, but also the phase, each sound ray 3 generated from the ultrasonic transmission source 11 is completely reflected on the reflection surface 14 and the amount of phase change accompanying the reflection at that time The reflection surface 14 is set so that tan ^-1 (2ad / D), which is the minimum value of the incident angle, is equal to or larger than θ ', which is the incident angle that satisfies the expression (6), so that φ has the same phase for all sound rays. Was determined. Thus, there is an effect that an ultrasonic convergence device capable of converging the ultrasonic energy generated by the ultrasonic wave transmission source 11 to the focal point 5 with higher energy efficiency as compared with the related art is obtained.

In all the sections perpendicular to the z-axis, the coefficient a for determining the shape of the reflecting surface 14 is determined by each sound ray 3 of the longitudinal ultrasonic wave generated from the ultrasonic transmission source 11 by the reflecting surface 1.
4, the phase shift amount associated with the reflection at that time is determined to be substantially the same value for all sound rays. There is an effect that an ultrasonic convergence device capable of improving the convergence efficiency of the sonic energy can be obtained.

In the above description, the case where the solid member on which the reflecting surface 14 is formed is arranged in the liquid has been described. However, it is not necessary that the entire solid member be arranged in the liquid. However, in all the sections perpendicular to the z-axis, the reflection surface 14 emitted from the ultrasonic wave source 11
It is needless to say that only a required propagation path of the longitudinal ultrasonic wave that reaches the focal point 5 after being reflected by the liquid crystal can be applied to a configuration in which the liquid is filled.

Embodiment 3 FIG. 14 is a perspective view showing the configuration of the ultrasonic liquid jetting device according to the third embodiment, and FIG. 15 is a sectional view thereof.

In this ultrasonic liquid jetting device, the ultrasonic focusing device shown in the first embodiment is used.
14 and 15, the same or corresponding parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted. 14 and 15, reference numeral 8 denotes a solid member on which the reflecting surface 4 is formed, and the reflecting surface 4 is a part of the surface of the solid member 8 that completely reflects the ultrasonic waves. The shape of the reflecting surface 4 is a part of the paraboloid of revolution, and is determined according to the method described in the first embodiment. Reference numeral 81 denotes a bottom surface of the solid member 8, and reference numeral 82 denotes a cylindrical through hole (ejection hole) formed from the lower end 41 of the reflection surface 4 toward the bottom surface 81 of the solid member 8.

In FIGS. 14 and 15, reference numeral 9 denotes a plate material, which is mounted on the acoustic radiation surface of the ultrasonic wave transmitting source 1.
Reference numeral 91 shown in FIG. 15 is a through hole provided in the plate member 9, and 10 is a gap provided between the plate member 9 and the solid member 8. 101
Is a liquid supply device, 101a is a liquid supply source, 101b is a liquid supply pipe, and the liquid supply device 101 is composed of the liquid supply source 101a, the liquid supply pipe 101b, and the like. The tip of the liquid supply pipe 101b is attached to the through hole 91 of the plate material 9. Reference numeral 12 denotes a liquid shielding plate, and the periphery of the space 10 is sealed by the shielding plate 12.

Note that the relative positional relationship between the ultrasonic wave transmitting source 1 and the reflecting surface 4 is the same as that described in the first embodiment. That is, although not shown, the ultrasonic transmission source 1
The ultrasonic transmission source 1 and the reflection source 4 are arranged such that the reflection surface 4 is rotationally symmetric with respect to an axis passing through the center of the opening plane and perpendicular to the opening plane, that is, an axis corresponding to the y-axis shown in FIG. The surface 4 is relatively arranged.

Next, the operation of the ultrasonic liquid ejection device shown in FIGS. 14 and 15 will be described. Liquid supply device 101
As a result, liquid is supplied from the liquid supply source 101a. This liquid is supplied to the liquid supply pipe 101b and the through-hole 9 of the plate material 9.
1 is led to the gap 10. The liquid guided to the gap 10 fills the gap 10 between the plate 9 and the solid member 8. Further, the reflecting surface 4 which is a part of the surface of the solid member 8
The space surrounded by the upper end 42 and the lower end 41 of the reflection surface 4 is also filled with the liquid. Further, the through hole 82 of the solid member 8 is also filled with the liquid. Void 1
Since the periphery of 0 is enclosed and sealed by the shielding plate 12,
If the diameter of the through hole 82 of the solid member 8 is large, the liquid filled in the gap 10 flows out only through the through hole 82. However, the diameter of the through hole 82 is made small so as not to flow out of the through hole 82 naturally by utilizing the surface tension of the liquid. Here, the expression “naturally” means that the ultrasonic wave is not radiated from the ultrasonic wave transmission source 1. When the diameter of the through-hole 82 is large and the liquid flows out from the through-hole 82, a small-diameter hole through which the liquid does not flow out naturally is formed near the focal point 5 on the opening surface of the through-hole 82 of the solid member 8. What is necessary is just to attach a board material.

In the state where the liquid is filled as described above, the ultrasonic wave is emitted from the ultrasonic wave transmitting source 1. The emitted ultrasonic waves reach the gap 10 filled with the liquid via the plate material 9 as shown by the sound ray 3 in FIG. further,
The ultrasonic waves reach the space surrounded by the reflecting surface 4 and the upper end 42 and the lower end 41 of the reflecting surface 4. This space is also filled with the liquid as described above. Each sound ray 3 of the ultrasonic wave is reflected by the reflecting surface 4 as shown in FIG. 15, and the reflected ultrasonic wave is surrounded by the reflecting surface 4 and the upper end 42 and the lower end 41 of the reflecting surface 4. Space and through hole 8
2 and converge on a focal point 5. The operation in which the ultrasonic wave emitted from the ultrasonic wave source 1 is reflected by the reflection surface 4 and converges on the focal point 5 is the same as that described in the first embodiment.

Naturally, the liquid flows through the through-hole 8 of the solid member 8.
When the ultrasonic wave is radiated from the ultrasonic transmission source 1 in a state where the liquid does not flow out of the liquid 2, the surface tension of the liquid is broken by the ultrasonic energy converged on the focal point 5, and a part of the liquid filling the through hole 82 is removed. Drops can be ejected. At this time, the liquid is sequentially supplied from the liquid supply device 101.

In the ultrasonic liquid jetting apparatus according to the third embodiment, if the liquid is water or ink, the water or ink can be jetted from the through-hole 82 as liquid droplets by ultrasonic waves. The coefficient a for determining the shape of the reflecting surface 4 described in the description of the first embodiment is the same as that of the first embodiment, since the characteristic of the ink regarding the ultrasonic wave is not much different from the characteristic regarding the water even when the liquid is the ink.
As described above, the ultrasonic energy can be efficiently collected at the focal point 5. In particular, when the liquid is ink and the solid member 8 is brass, zinc, magnesium, or aluminum, the ultrasonic energy can be transmitted with high efficiency by determining the coefficient a to the value shown in the first embodiment in each combination. Focused on focus 5.

In the third embodiment, if the electrodes of the ultrasonic wave transmitting source 1 are in direct contact with the liquid, corrosion may occur. Therefore, the plate member 9 serves to protect the electrodes from corrosion. Further, when the liquid is charged, it also plays a role of insulating the liquid from the ultrasonic wave transmission source 1. Further, by using a plate material 9 whose acoustic impedance has an intermediate value between the acoustic impedance of the ultrasonic wave transmitting source 1 and the acoustic impedance of the liquid, it can also serve as an acoustic matching layer.

As described above, according to the third embodiment, the liquid supplied from the liquid supply device 101 is ejected by the ultrasonic wave using the ultrasonic focusing device described in the first embodiment. Thus, there is an effect that the energy of the ultrasonic wave radiated from the ultrasonic wave transmitting source 1 can be efficiently converged to the focal point 5, and further, an ultrasonic liquid ejecting apparatus capable of efficiently ejecting the liquid by the converged ultrasonic wave is obtained.

Although FIG. 15 shows a case where the focal point 5 is located substantially on the same plane as the bottom surface 81 of the solid member 8, the present invention is not limited to this. What is necessary is just to be near the central axis of the through hole 82 and near the bottom surface 81 of the solid member 8, and the same effect as described above can be obtained.

In the above description, the case where the through hole 82 is formed in a columnar shape has been described.
The shape is not limited to this, and a hole having a tapered side surface may be used. That is, it may be formed in a conical shape. If the diameter of the conical hole is such that the inside diameter of the side where the droplet is ejected is smaller than the inside diameter of the lower end portion 41 side of the reflection surface 4, the effect that the droplet can be ejected more efficiently is obtained. can get.

Embodiment 4 FIG. 16 is a perspective view showing the configuration of the ultrasonic liquid jetting device according to the fourth embodiment, and FIG. 17 is a sectional view thereof. The ultrasonic liquid jetting device according to the fourth embodiment uses the ultrasonic focusing device described in the second embodiment. In FIGS. 16 and 17, the same or corresponding portions as those in FIGS. The same reference numerals are given and the description is omitted.

Referring to FIG. 16 and FIG.
Is a part of a paraboloid having a uniform shape along a certain direction, and is determined according to the method described in the second embodiment. is there. Reference numeral 83 denotes a rectangular parallelepiped through hole (ejection hole) provided from the lower end 41a of the reflection surface 14 to the bottom surface 81 of the solid member 8. In the fourth embodiment, the relative positional relationship between the ultrasonic wave transmitting source 11 and the reflecting surface 14 is the same as that described in the second embodiment.

Next, the operation of the ultrasonic liquid ejection device shown in FIGS. 16 and 17 will be described. Liquid supply device 101
Thereby, the liquid is guided from the liquid supply source 101a to the gap 10 via the liquid supply pipe 101b and the through hole 91 of the plate material 9. The liquid led to the gap 10 is a plate member 9 and a solid member 8.
Is filled in the gap 10. Further, 2 of the solid member 8
The space having the inner side surface constituted by the three reflection surfaces 14 and the through hole 83 of the solid member 8 are filled. The periphery of the gap 10 is surrounded and sealed by a shielding plate 12. The cross-sectional area of the through-hole 83 is made small so that the liquid filled in this way does not flow out of the through-hole 83 naturally.

In the state where the liquid is filled as described above, an ultrasonic wave is emitted from the ultrasonic wave transmitting source 11. The emitted ultrasonic waves reach the space 10 filled with the liquid via the plate material 9 as shown by the sound ray 3 in FIG.
The light is reflected by the reflector 14 and converges on the focal point 5. The operation in which the ultrasonic wave emitted from the ultrasonic wave source 11 is reflected by the reflection surface 14 and converges on the focal point 5 is the same as that described in the second embodiment.

When the ultrasonic wave is radiated from the ultrasonic wave transmitting source 11 in a state where the liquid does not spontaneously flow out of the through-hole 83 of the solid member 8, the ultrasonic energy converged on the focal point 5 fills the through-hole 83. The surface tension of the liquid is broken, and a part of the liquid filling the through hole 83 is ejected as droplets. At this time, the fact that the liquid is sequentially supplied from the liquid supply device 101 means that
This is the same as in the third embodiment.

Also in the ultrasonic liquid jetting device of the fourth embodiment, if the liquid is water or ink, the water or ink can be jetted as droplets by ultrasonic waves. Reflecting surface 4 shown in the description of the second embodiment
The coefficient a for determining the shape of the above is such that even when the liquid is ink, the characteristics of the ink relating to the ultrasonic waves are not so different from the characteristics relating to the water, so that the ultrasonic energy can be efficiently determined if it is determined as described in the second embodiment. Can be converged to the focal point 5. In particular, when the liquid is ink and the solid member 8 is brass, zinc, magnesium, or aluminum, the coefficient “a” can transmit ultrasonic energy with high efficiency if each of the combinations has the value shown in the second embodiment. It can converge on the focal point 5. In addition,
Also in the fourth embodiment, the plate member 9 plays the same role as in the third embodiment.

As described above, according to the fourth embodiment, the liquid supplied from the liquid supply device is applied to the opening of the through-hole 83 by the ultrasonic wave using the ultrasonic convergence device described in the second embodiment. The liquid is ejected from the opening, so that the ultrasonic liquid can be efficiently ejected from the opening of the through-hole 83 by the energy of the ultrasonic wave radiated from the ultrasonic wave transmitting source 11 efficiently focused on the focal point 5. There is an effect that the device can be obtained.

Note that the focal point 5 shown in FIG.
However, the position of the focal point 5 is not limited to this, but near the center axis of the through hole 83 of the solid member 8 and near the bottom surface 81 of the solid member 8. The same effect can be obtained.

Further, the side surface of the through hole 83 may be tapered. In the case of such a shape, in particular, if the taper is provided so that the opening area of the through hole 83 on the droplet discharge side is smaller than the opening area on the side in contact with the lower end portion 41a of the reflection surface 14, The effect that droplets can be efficiently discharged can be obtained.

[0135]

As described above, according to the present invention, the reflection surface is constituted by a part of the surface of the solid member, and the incident angle of each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic wave source is determined. In relation to
The longitudinal wave ultrasonic wave is completely reflected in the liquid and configured to converge to a predetermined focal point of the longitudinal wave ultrasonic wave, and the amount of phase shift accompanying reflection when each sound ray is reflected is reduced. Since the reflection surface is formed in a shape having the same phase with respect to each sound ray, there is an effect that the ultrasonic energy generated by the ultrasonic wave transmission source can be efficiently focused on the focal point.

According to the present invention, the unit of length is [m], the density of the liquid, the sound velocity of the longitudinal ultrasonic wave in the liquid, the density of the solid member, the sound velocity of the longitudinal ultrasonic wave in the solid member. And a is a coefficient that is a value equal to or greater than a predetermined value having a unit of [m ⁻¹ ] determined by the sound speed of the transverse ultrasonic wave in the solid member, and the length of the diameter of the upper end surface of the paraboloid of revolution is When D is given, a curve given by a quadratic function defining the cross section of the paraboloid of revolution with the rotation axis as the y-axis has a line perpendicular to the y-axis at the origin intersecting the y-axis and the x-axis. Y =
(2a / D) a parabola defined by x ^2, is constituted by a part of the paraboloid shape, converging the respective sound ray of the longitudinal wave ultrasonic waves to the focal point of the paraboloid shape At the incident angle at which each sound ray is completely reflected in parallel with the rotation axis of the paraboloid of revolution constituting the reflection surface, at a position where each sound ray is radiated to the reflection surface. Since the ultrasonic transmission source is arranged, the effect of efficiently converging the ultrasonic energy by the sound rays reflected by the reflection surface formed by a part of the paraboloid of revolution to the focal point is achieved. is there.

According to the present invention, the diameter d of the lower end face of the paraboloid of revolution and the diameter D of the upper end face in the region where each sound ray of the longitudinal ultrasonic wave emitted from the ultrasonic wave source is completely reflected. Y = determines the shape of the paraboloid of revolution within the range given by
(2a / D) the coefficient a of the parabola defined by x ^2, the density of the liquid [rho _1, the longitudinal wave ultrasonic sound speed [nu _l in the liquid, the density [rho ₂ of the solid member, the vertical of the solid member in Within the range of not less than the first incident angle θ ′ at which the phase of the reflectance defined by the sound velocity ν _L of the wave ultrasonic wave and the sound velocity ν _S of the transverse ultrasonic wave in the solid member becomes −180 ° and not more than 90 °. Since the angle of incidence is configured to be a value that is limited, when each sound ray reflected on the paraboloid of revolution by the parabola defined by the coefficient a converges to the focal point, It does not converge on the focal point, and there is an effect that the ultrasonic energy from each sound ray can be efficiently converged on the focal point.

According to the present invention, the unit of length is [m], and the density of the liquid, the speed of sound of the longitudinal ultrasonic wave in the liquid, the density of the solid member, the density of the longitudinal ultrasonic wave in the solid member, The sound velocity, and a coefficient having a unit of [m ^-1 ] which is a value equal to or more than a predetermined value determined by the sound velocity of the transverse ultrasonic wave in the solid member, a represents a separation distance between upper ends of two paraboloids. D, where the symmetry axis of the two paraboloids is the y-axis, the curve given by a quadratic function that defines the cross section of the two paraboloids is y
Line at the origin which intersects the axis perpendicular to the said y-axis is represented by y = (2a / D) x 2 is the x axis, by a part of the paraboloid is uniform in a direction perpendicular to the cross-section Since it is configured to have a reflecting surface having a shape that converges each sound ray of the longitudinal wave ultrasonic wave emitted from the ultrasonic wave transmitting source in parallel with the symmetry axis to the focal point of the paraboloid, There is an effect that the ultrasonic energy generated by the ultrasonic transmission source, which is reflected by the reflection surface formed by a part of the two object planes, can be efficiently focused on the focal point.

According to the present invention, when the distance between the upper end surfaces of the two paraboloids is D in a region where each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic wave transmission source is completely reflected. the coefficient a of the parabola defined by y = (2a / D) x 2 that determines the parabolic shape of the density of the liquid [rho _1, the longitudinal wave ultrasonic sound speed [nu _l in the liquid, the density of the solid member [rho _2. The phase of the reflectance defined by the sound velocity ν _L of the longitudinal ultrasonic wave in the solid member and the sound velocity ν _S of the transverse ultrasonic wave in the solid member is −18.
Since the angle of incidence is limited within a range of not less than the first incident angle θ ′ of 0 ° and not more than 90 °, the two parabolas are defined by the parabola defined by the coefficient a. When each sound ray reflected on the surface converges to the focal point,
There is no longer converging to the focal point including the opposite phase, and there is an effect that the ultrasonic energy from each sound ray can be efficiently converged to the focal point.

According to the present invention, the range of the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave source on the reflection surface of each sound ray is determined such that each sound ray is completely reflected and each sound ray is reflected. Since the difference between the sound rays of the phase shift amount due to the reflection is configured to be in a range that is substantially zero, when the sound rays reflected on the reflection surface converge to the focal point, the opposite phase Therefore, there is an effect that the ultrasonic energy by each sound ray can be efficiently converged to the focal point by making the phase variation substantially zero.

According to the present invention, the range in which the incident angle of the longitudinal ultrasonic wave radiated from the ultrasonic wave source to each sound ray on the reflecting surface is set such that each sound ray is completely reflected and each sound ray is reflected. Since the maximum value of the difference in the amount of phase shift due to the reflection of the line is configured to be in a range of approximately 40 ° or less, when each of the sound rays reflected on the reflection surface converges to a focal point, the sound ray Thus, there is an effect that the ultrasonic energy by the laser beam can be converged to the focal point with high energy efficiency.

According to the present invention, when the unit of length is [m] and the liquid is water or ink and the solid member is brass, the value of the coefficient a is about 1.3 × 10 ³ [m ^−1]. ], There is an effect that the efficiency of energy convergence to the focal point when the reflecting surface made of brass is used can be improved.

According to the present invention, when the liquid is water or ink and the solid member is zinc, and the unit of length is [m], the value of the coefficient a is about 1 × 10 ³ [m ⁻¹ ] or more. , The effect of improving the energy convergence efficiency to the focal point when the reflecting surface made of zinc is used.

According to the present invention, when the unit of length is represented by [m], where the liquid is water or ink and the solid member is magnesium, the value of the coefficient a is approximately 0.8 × 10 ^3.
Since the configuration is made so as to be [m ^-1 ] or more, there is an effect that the energy convergence efficiency to the focal point can be improved when a reflecting surface made of magnesium is used.

According to the present invention, when the liquid is water or ink and the solid member is aluminum, and the unit of length is [m], the value of the coefficient a is about 0.7 × 10 ^3.
Since it is configured so as to be [m ^-1 ] or more, there is an effect that the energy convergence efficiency to the focus when the reflecting surface made of aluminum is used can be improved.

According to the present invention, the relationship between the ultrasonic wave source radiating the longitudinal ultrasonic wave into the liquid and the incident angle of each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic wave transmitting source is as follows. The longitudinal wave is completely reflected in the liquid and converged to a predetermined focal point of the longitudinal wave, and the phase associated with the reflection when each sound ray is reflected by the reflecting surface. An ultrasonic convergence device including a solid member having a reflection surface disposed in the liquid, the shift amount being in the same phase with respect to each sound ray, a liquid supply device that sequentially supplies the liquid, and the liquid Since the liquid is ejected by the longitudinal ultrasonic wave inside, the ejection hole is configured near the focal point, so that the ultrasonic energy generated by the ultrasonic transmission source is efficiently used for ejecting the liquid. There is an effect that can be done.

According to the present invention, the reflecting surface constituted by the solid member of the ultrasonic focusing device and disposed in the liquid has a unit of length [m], the density of the liquid, the longitudinal wave in the liquid. A value greater than or equal to a predetermined value having a unit of [m ^-1 ] determined by the sound speed of the sound wave, the density of the solid member, the sound speed of the longitudinal ultrasonic wave in the solid member, and the sound speed of the transverse ultrasonic wave in the solid member Where a is a coefficient, and D is the length of the diameter of the upper end surface of the paraboloid of revolution. A curve given by a quadratic function defining the cross section of the paraboloid of revolution with the y-axis as the axis of rotation. Is a parabola defined by y = (2a / D) x ² where a line orthogonal to the y-axis at the origin intersecting the y-axis is the x-axis, and is defined by a part of the shape of the rotating paraboloid. And configured such that each sound ray of the longitudinal ultrasonic wave is converged at the focal point of the paraboloid of revolution. The ultrasonic transmission source is positioned parallel to the rotation axis of the paraboloid of revolution constituting the reflection surface, at an incident angle at which each sound ray is completely reflected, and at a position where each sound ray is radiated to the reflection surface. Since it is configured to be arranged, the ultrasonic energy by each sound ray reflected by the reflection surface formed by a part of the paraboloid of revolution, efficiently converge to the focus by an ultrasonic focusing device, There is an effect that the ultrasonic energy generated by the ultrasonic transmission source can be efficiently used for ejecting the liquid.

According to the present invention, the diameter d of the lower end face of the paraboloid of revolution and the upper end face of the paraboloid of revolution in the ultrasonic convergence device in a region where each sound ray of the longitudinal ultrasonic wave emitted from the ultrasonic wave source is completely reflected. The coefficient a of a parabola defined by y = (2a / D) × ² , which determines the shape of the paraboloid within the range defined by the diameter D, is defined by the density of the liquid ρ ₁ and the longitudinal wave in the liquid. wave sound velocity [nu _l, the density [rho ₂ of the solid member, the longitudinal wave ultrasonic sound speed [nu _L of the solid member in the solid member in transverse ultrasonic wave sound velocity [nu phase of the reflection factor defined by _S -180 Since the angle of incidence is limited within a range of not less than the first incident angle θ ′ and not more than 90 °, the coefficient a
When the sound rays reflected on the paraboloid of revolution defined by the parabola converge to the focal point, they do not converge to the focal point including the opposite phase, and the ultrasonic energy by the respective sound rays is transmitted to the focal point. There is an effect that the convergence can be efficiently performed and the ultrasonic energy generated by the ultrasonic transmission source can be efficiently used for ejecting the liquid.

According to the present invention, the reflecting surface of the ultrasonic convergence device has a unit of length [m], and has a liquid density,
The sound velocity of the longitudinal ultrasonic wave in the liquid, the density of the solid member, the sound velocity of the longitudinal ultrasonic wave in the solid member, and a value equal to or higher than a predetermined value determined by the sound velocity of the transverse ultrasonic wave in the solid member When a coefficient having a unit of [m ^-1 ] is a, a distance between upper ends of two paraboloids is D, and a symmetry axis of the two paraboloids is y-axis, the two paraboloids are given. 2 that defines the cross section of
The curve given by the following function is such that the line orthogonal to the y-axis at the origin crossing the y-axis is the x-axis, y = (2a /
D) is represented by x ^2, converges the respective sound ray of the longitudinal ultrasonic wave is constituted by a part of the paraboloid is uniform in a direction perpendicular to the cross section at the focus of the parabolic shape Therefore, the ultrasonic energy by each of the sound rays reflected by the reflecting surface formed by a part of the two paraboloids of the ultrasonic focusing device is efficiently converged to the focal point, and the ultrasonic transmission is performed. There is an effect that the ultrasonic energy generated at the source can be efficiently used for ejecting the liquid.

According to the present invention, the distance between the upper end surfaces of the two paraboloids in the ultrasonic focusing device is set to D in a region where each sound ray of the longitudinal ultrasonic wave emitted from the ultrasonic transmission source is completely reflected. Where y = determines the shape of the paraboloid
(2a / D) the coefficient a of the parabola defined by x ^2, the density of the liquid [rho _1, the longitudinal wave ultrasonic sound speed [nu _l in the liquid, the density [rho ₂ of the solid member, the longitudinal waves of the solid member in Ultrasonic sound speed ν
_L , the incident angle is limited within a range of not less than the first incident angle θ ′ at which the phase of the reflectance defined by the sound velocity ν _S of the transverse ultrasonic wave in the solid member is −180 ° and not more than 90 °. Since each sound ray reflected on two parabolas by the parabola defined by the coefficient a converges to the focal point, it converges to the focal point including the opposite phase. In addition, there is an effect that the ultrasonic energy from each sound ray is efficiently converged to the focal point, and the ultrasonic energy generated by the ultrasonic transmission source can be efficiently used for ejecting the liquid.

According to the present invention, the range of the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave transmitting source in the ultrasonic convergence device on the reflecting surface of each sound ray is completely reflected by each sound ray. In addition, since the difference between the respective sound rays in the phase shift amount due to the reflection of the respective sound rays is set to be in a range that becomes substantially zero, when the respective sound rays reflected on the reflection surface converge to the focal point. In addition, there is an effect that the ultrasonic energy which does not converge on the focal point including the reverse phase can be efficiently used for ejecting the liquid.

According to the present invention, the range in which the incident angle of the longitudinal ultrasonic waves radiated from the ultrasonic wave source in the ultrasonic convergence device to the reflecting surface of each sound ray is completely reflected by each sound ray is determined. And, since the maximum value of the difference of the phase shift amount due to the reflection of each sound ray is configured to be in a range of about 40 ° or less,
There is an effect that the ultrasonic energy by each sound ray converged to the focal point with high energy efficiency can be efficiently used for ejecting the liquid.

According to the present invention, the reflecting surface of the ultrasonic convergence device is constituted by a solid member made of brass, is disposed in a liquid such as water or ink, and a unit of length is expressed by [m]. Then, the value of the coefficient a becomes approximately 1.3 × 10
³ [m ^-1 ] or more, the efficiency of energy convergence to the focal point by the reflective surface made of brass is improved, and the ultrasonic energy by each of the sound rays that has been efficiently converged is ejected from the liquid. There are effects that can be used.

According to the present invention, the reflecting surface of the ultrasonic focusing device is constituted by a solid member made of zinc, is arranged in a liquid such as water or ink, and the unit of length is expressed by [m]. Then, the value of the coefficient a is approximately 1 × 10 ³
[M ^-1 ] or more, the efficiency of energy convergence to the focal point by the reflecting surface made of zinc is improved, and the ultrasonic energy by each of the efficiently converged sound rays is ejected to the liquid. There are effects available.

According to the present invention, the reflecting surface of the ultrasonic focusing device is made of a solid member made of magnesium, and is arranged in a liquid such as water or ink.
When the unit of length is represented by [m], the value of the coefficient a is set to approximately 0.
Since it is configured so as to be 8 × 10 ³ [m ⁻¹ ] or more, the energy convergence efficiency to the focal point by the reflection surface made of magnesium is improved, and the ultrasonic energy by each of the sound rays efficiently converged is reduced. There is an effect that can be used for jetting liquid.

According to the present invention, the reflecting surface of the ultrasonic focusing device is constituted by a solid member made of aluminum, and is disposed in a liquid such as water or ink.
When the unit of length is represented by [m], the value of the coefficient a is set to approximately 0.
Since it is configured so as to be 7 × 10 ³ [m ⁻¹ ] or more, the efficiency of energy focusing to the focal point by the reflecting surface made of aluminum is improved, and the ultrasonic energy by each sound ray efficiently focused is improved. There is an effect that can be used for jetting liquid.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of an ultrasonic convergence device according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of an ultrasonic convergence device according to Embodiment 1 of the present invention.

FIG. 3 is an operation explanatory diagram showing a boundary surface between a liquid and a solid, a transmitted wave of a longitudinal wave, a transmitted wave of a transverse wave, an incident angle, and the like of the ultrasonic focusing apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating an ultrasonic focusing apparatus according to Embodiment 1 of the present invention in which an incident angle is in a range of 0 ° to 90 °;
FIG. 4 is a characteristic diagram showing an absolute value and a phase of a reflectance on a reflection surface when a solid is brass.

FIG. 5 is a diagram illustrating an ultrasonic convergence device according to Embodiment 1 of the present invention, in which the liquid is water and the incident angle is in the range of 0 ° to 90 °.
FIG. 4 is a characteristic diagram showing an absolute value and a phase of a reflectance on a reflection surface when a solid is zinc.

FIG. 6 is a diagram illustrating an ultrasonic convergence device according to Embodiment 1 of the present invention, in which the liquid is water and the incident angle is in a range of 0 ° to 90 °.
FIG. 4 is a characteristic diagram showing an absolute value and a phase of a reflectance on a reflection surface when a solid is magnesium.

FIG. 7 is a diagram illustrating a state in which the liquid is water when the incident angle of the ultrasonic convergence device according to the first embodiment of the present invention is in the range of 0 ° to 90 °;
FIG. 4 is a characteristic diagram showing an absolute value and a phase of a reflectance on a reflection surface when a solid is aluminum.

FIG. 8 is a characteristic diagram in which an amplitude at a focal point of each sound ray of the ultrasonic convergence device according to the first embodiment of the present invention is calculated with a coefficient a in a range of 0 to 2;

FIG. 9 is a characteristic diagram in which an amplitude at a focal point of each sound ray of the ultrasonic convergence device according to the first embodiment of the present invention is calculated with a coefficient a in a range of 0 to 2;

FIG. 10 shows the amplitude at the focal point of each sound ray of the ultrasonic focusing apparatus according to Embodiment 1 of the present invention,
6 is a characteristic diagram calculated in the range of FIG.

FIG. 11 shows the amplitude at the focal point of each sound ray of the ultrasonic focusing apparatus according to Embodiment 1 of the present invention,
6 is a characteristic diagram calculated in the range of FIG.

FIG. 12 is a schematic diagram showing a configuration of an ultrasonic convergence device according to Embodiment 2 of the present invention.

FIG. 13 is a cross-sectional view showing a configuration of an ultrasonic convergence device according to Embodiment 2 of the present invention.

FIG. 14 is a perspective view showing a configuration of an ultrasonic liquid ejection device according to Embodiment 3 of the present invention.

FIG. 15 is a cross-sectional view illustrating a configuration of an ultrasonic liquid ejection device according to Embodiment 3 of the present invention.

FIG. 16 is a perspective view showing a configuration of an ultrasonic liquid ejection apparatus according to Embodiment 4 of the present invention.

FIG. 17 is a cross-sectional view showing a configuration of an ultrasonic liquid ejection device according to Embodiment 4 of the present invention.

FIG. 18 is an explanatory view showing a conventional ultrasonic convergence device.

FIG. 19 is an explanatory diagram showing a conventional ultrasonic convergence device.

FIG. 20 is an explanatory view showing a conventional ultrasonic convergence device.

[Explanation of symbols]

1, 11 ultrasonic transmission source, 3 sound rays, 4, 14 reflecting surface, 5 focal points, 8 solid members, 82, 83 through holes (ejection holes), 101 liquid supply device.

 ────────────────────────────────────────────────── ─── Continued on front page (72) Inventor Hiroshi Fukumoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (22)

[Claims] 1. An ultrasonic wave source for emitting longitudinal ultrasonic waves into a liquid, and a longitudinal wave ultrasonic wave arranged in the liquid and emitted from the ultrasonic wave source into the liquid, the ultrasonic wave being transmitted into the liquid. In the ultrasonic convergence device constituted by a solid member having a reflection surface for converging, the reflection surface is constituted by a part of the surface of the solid member, and the shape is radiated from the ultrasonic transmission source. In relation to the incident angle of each sound ray of the longitudinal ultrasonic wave, the longitudinal ultrasonic wave is completely reflected in the liquid and is configured to converge to a predetermined focal point of the longitudinal ultrasonic wave. An ultrasonic convergence apparatus, wherein each of the sound rays is configured to have a phase shift amount caused by reflection when the sound rays are reflected by the reflection surface so as to be in phase with respect to each of the sound rays. 2. The reflection surface has a unit of length [m], a density of a liquid, a sound velocity of a longitudinal ultrasonic wave in the liquid, a density of a solid member, and a sound velocity of a longitudinal ultrasonic wave in the solid member. And a is a coefficient that is a value equal to or greater than a predetermined value having a unit of [m ⁻¹ ] determined by the sound speed of the transverse ultrasonic wave in the solid member, and the length of the diameter of the upper end surface of the paraboloid of revolution is When D is given, a curve given by a quadratic function defining the cross section of the paraboloid of revolution with the rotation axis as the y-axis has a line perpendicular to the y-axis at the origin intersecting the y-axis and the x-axis. Y = (2a / D) × ² , which is constituted by a part of the shape of the rotating paraboloid and focuses each sound ray of the longitudinal ultrasonic wave on the focus of the rotating paraboloid. The ultrasonic transmission source, in parallel with the rotation axis of the paraboloid of revolution constituting the reflection surface, The ultrasonic convergence apparatus according to claim 1, wherein the sound ray is arranged at an incident angle at which the sound ray is completely reflected, and the sound ray is radiated to the reflection surface. 3. The diameter of the lower end face of the paraboloid of revolution is d, the diameter of the upper end face of the paraboloid of revolution is D, the density of the liquid is ρ ₁ , and the speed of sound of longitudinal ultrasonic waves in the liquid is ν _l. , The density of the solid member is ρ
₂ , when the sound velocity of the longitudinal ultrasonic wave in the solid member is ν _L and the sound velocity of the transverse ultrasonic wave in the solid member is ν _S , each sound ray of the longitudinal ultrasonic wave emitted from the ultrasonic wave source In the area where the light is completely reflected, the diameter d of the lower end face and the diameter D of the upper end face
Which determines the shape of the paraboloid of revolution within the range defined by the diameter d of the lower end face and the diameter D of the upper end face within the range defined by y = (2a / D) × ² Coefficient a
The density ρ _{1 of} the liquid, the sound velocity ν _l of the longitudinal ultrasonic wave in the liquid, the density ρ _{2 of} the solid member, the sound velocity ν _L of the longitudinal ultrasonic wave in the solid member, the transverse wave in the solid member The angle of incidence is limited within a range of not less than the first incident angle θ ′ at which the phase of the reflectance specified by the sound velocity ν _S of the ultrasonic wave is −180 ° and not more than 90 °. The ultrasonic focusing device according to claim 2, wherein 4. The reflecting surface has a unit of length [m], and includes a density of a liquid, a sound velocity of longitudinal ultrasonic waves in the liquid, a density of a solid member, and a density of a longitudinal ultrasonic wave in the solid member. The sound velocity is a value equal to or higher than a predetermined value determined by the sound velocity of the transverse ultrasonic wave in the solid member [m
^-1 ] is a coefficient, a distance between upper ends of two paraboloids is D, and a symmetry axis of the two paraboloids is y-axis. A curve given by a quadratic function that defines the y-axis at the origin crossing the y-axis
A line perpendicular to the axis is represented by y = (2a / D) x ² which is an x-axis, and the longitudinal ultrasonic wave is constituted by a part of the paraboloid which is uniform in a direction perpendicular to the cross section. And the ultrasonic transmission source is configured so that each of the sound rays is completely reflected in parallel with the symmetry axis of the paraboloid constituting the reflection surface. 2. The ultrasonic convergence device according to claim 1, wherein each sound ray is radiated to the reflection surface at an angle. 5. The distance between the lower ends of the two paraboloids is d,
The separation distance of the upper end face of the paraboloid is D, and the density of the liquid is ρ
₁ , the sound speed of longitudinal ultrasonic waves in the liquid is ν _l , the density of the solid member is ρ ₂ , and the sound speed of longitudinal ultrasonic waves in the solid member is ν
_L , when the sound speed of the shear wave ultrasonic wave in the solid member is ν _S , in a region where each sound ray of the longitudinal wave ultrasonic wave emitted from the ultrasonic wave source is completely reflected, determines the shape of the paraboloid. The coefficient a of a parabola defined by y = (2a / D) x ² is given by
The density ρ _{1 of} the liquid, the speed of sound ν of longitudinal ultrasonic waves in the liquid
_l , density ρ _{2 of} the solid member, sound velocity ν _L of longitudinal ultrasonic wave in the solid member, sound velocity ν of transverse ultrasonic wave in the solid member
_The incident angle is limited within a range of not less than 90 ° and not less than the first incident angle θ ′ at which the phase of the reflectance specified by _S is −180 °. Ultrasonic convergence device. 6. The range of the angle of incidence of the longitudinal ultrasonic waves radiated from the ultrasonic wave transmitting source on the reflection surface of each sound ray is such that each sound ray is completely reflected and that each sound ray is reflected. The ultrasonic convergence apparatus according to any one of claims 2 to 5, wherein a difference in a phase shift amount between the sound rays is substantially zero. 7. The range of the incident angle of the longitudinal ultrasonic waves emitted from the ultrasonic wave transmitting source to the reflection surface of each sound ray is such that each sound ray is completely reflected and that each sound ray is reflected. The ultrasonic focusing apparatus according to any one of claims 2 to 5, wherein the maximum value of the difference in the accompanying phase shift amount is in a range of about 40 ° or less. 8. When the liquid is water or ink and the solid member is brass, and the unit of length is [m], the value of the coefficient a is about 1.3 × 10 ³ [m ⁻¹ ] or more. The ultrasonic focusing apparatus according to any one of claims 2 to 5, wherein: 9. When the liquid is water or ink and the solid member is zinc, and the unit of length is represented by [m], the value of the coefficient a is about 1 × 10 ³ [m ⁻¹ ] or more. The ultrasonic convergence device according to any one of claims 2 to 5, characterized in that: 10. When the length of the liquid is water or ink and the solid member is magnesium, and the unit of length is [m], the value of the coefficient a is about 0.8 × 10 ³ [m ⁻¹ ] or more. The ultrasonic focusing apparatus according to any one of claims 2 to 5, wherein: 11. When the liquid is water or ink and the solid member is aluminum, and the unit of length is [m], the value of the coefficient a is about 0.7 × 10 ³ [m ⁻¹ ] or more. The ultrasonic focusing apparatus according to any one of claims 2 to 5, wherein: 12. A longitudinal ultrasonic wave according to a relationship between an ultrasonic wave transmitting source that emits a longitudinal ultrasonic wave into a liquid and an incident angle of each sound ray of the longitudinal ultrasonic wave radiated from the ultrasonic transmitting source. Is completely reflected in the liquid and converged to a predetermined focal point of the longitudinal ultrasonic wave, and the amount of phase shift accompanying reflection when each sound ray is reflected by the reflecting surface is An ultrasonic convergence device including a solid member having a reflection surface disposed in the liquid and having a shape that is in phase with respect to sound rays; a liquid supply device that sequentially supplies the liquid; and a longitudinal wave in the liquid. The liquid is ejected by ultrasonic waves,
An ultrasonic liquid ejecting apparatus, comprising: an ejecting hole formed near the focal point. 13. A reflecting surface formed of a solid member and arranged in a liquid, the unit of length is [m], the density of the liquid, the sound speed of longitudinal ultrasonic waves in the liquid, the density of the solid member, The coefficient a, which is a value equal to or larger than a predetermined value having a unit of [m ^-1 ] determined by the sound speed of longitudinal ultrasonic waves in the solid member and the sound speed of transverse ultrasonic waves in the solid member, Assuming that the length of the diameter of the upper end surface of the surface shape is D, a curve given by a quadratic function defining the cross section of the paraboloid of revolution with the rotation axis as the y-axis is the origin at which the y-axis intersects. Is a parabola defined by y = (2a / D) x ² where the line orthogonal to the y-axis is the x-axis, and is constituted by a part of the shape of the paraboloid of revolution. Each sound ray has a shape that converges on the focal point of the paraboloid of revolution, and an ultrasonic wave source forms the reflection surface. In parallel with the rotation axis of the rotating paraboloid to be formed, at an incident angle at which each sound ray is completely reflected, an ultrasonic convergence device arranged at a position where each sound ray is radiated to the reflection surface, A liquid supply device for sequentially supplying the liquid, and the liquid is ejected by longitudinal ultrasonic waves in the liquid,
13. The ultrasonic liquid ejection device according to claim 12, further comprising an ejection hole configured near the focal point. 14. The ultrasonic wave focusing apparatus, wherein the diameter of the lower end surface of the paraboloid of revolution is d, the diameter of the upper end surface of the paraboloid of revolution is D, the density of the liquid is ρ ₁ , and the longitudinal ultrasonic waves in the liquid are When the sound speed of ν _l , the density of the solid member is ρ ₂ , the sound speed of the longitudinal ultrasonic wave in the solid member is ν _L , and the sound speed of the transverse ultrasonic wave in the solid member is ν _S , an ultrasonic wave source In the region where each sound ray of longitudinal ultrasonic waves radiated from the target is completely reflected, the shape of the paraboloid of revolution within the range defined by the diameter d of the lower end face and the diameter D of the upper end face is determined as y = ( 2a / D) × ² , the coefficient a of the parabola defined by x2, the density ρ _{1 of} the liquid, the sound velocity ν _l of longitudinal ultrasonic waves in the liquid, the density ρ of the solid member
_2. The first incident angle θ ′ at which the phase of the reflectance defined by the sound velocity ν _L of the longitudinal ultrasonic wave in the solid member and the sound velocity ν _S of the transverse ultrasonic wave in the solid member becomes −180 ° or more. And 90
14. The ultrasonic liquid ejecting apparatus according to claim 13, wherein the incident angle is limited to a value within the following range. 15. The reflecting surface of the ultrasonic focusing device has a unit of length [m], and has a density of a liquid, a sound velocity of longitudinal ultrasonic waves in the liquid, a density of a solid member, and a density of the solid member. It is a value equal to or more than a predetermined value determined by the sound speed of longitudinal ultrasonic waves and the sound speed of transverse ultrasonic waves in the solid member [m
^-1 ] is a coefficient, a distance between upper ends of two paraboloids is D, and a symmetry axis of the two paraboloids is y-axis. A curve given by a quadratic function that defines the y-axis at the origin crossing the y-axis
A line perpendicular to the axis is represented by y = (2a / D) x ² which is an x-axis, and the longitudinal ultrasonic wave is constituted by a part of the paraboloid which is uniform in a direction perpendicular to the cross section. Is a shape that converges each sound ray to the focal point of the parabolic surface, and the ultrasonic wave transmission source in the ultrasonic convergence device, wherein each sound ray is parallel to the symmetry axis of the paraboloid constituting the reflection surface. 13. The ultrasonic liquid ejection device according to claim 12, wherein each of the sound rays is radiated to the reflection surface at an incident angle at which the light is completely reflected. 16. The distance between the lower ends of two paraboloids in the ultrasonic focusing device is d, the distance between the upper ends of the paraboloids is D, the density of the liquid is ρ ₁ , and the longitudinal wave in the liquid is When the sound speed of the ultrasonic wave is ν _l , the density of the solid member is ρ ₂ , the sound speed of the longitudinal ultrasonic wave in the solid member is ν _L , and the sound speed of the transverse ultrasonic wave in the solid member is ν _S , the ultrasonic wave In a region where each sound ray of longitudinal ultrasonic waves radiated from the transmission source is completely reflected, a coefficient a of a parabola defined by y = (2a / D) × ² which determines the shape of the paraboloid is set to the liquid density [rho _1, the longitudinal wave ultrasonic sound speed [nu _l in the liquid, said solid member of density [rho _2, the longitudinal wave ultrasonic sound speed [nu _L of the solid member in, transverse ultrasonic wave sound velocity of the solid member in The phase of the reflectance specified by ν _S is −
16. The ultrasonic liquid ejection apparatus according to claim 15, wherein the incident angle is limited within a range of not less than 180 [deg.] And not more than 90 [deg.]. 17. The range of angles of incidence of longitudinal ultrasonic waves radiated from an ultrasonic transmission source in an ultrasonic convergence device on a reflecting surface of each sound ray is such that each sound ray is completely reflected and each sound ray is reflected. 14. The method according to claim 13, wherein a difference between the sound rays in a phase shift amount due to reflection of the rays is substantially zero.
7. The ultrasonic liquid jetting device according to any one of 6. 18. The range in which the incident angle of the longitudinal ultrasonic waves emitted from the ultrasonic wave transmission source in the ultrasonic convergence device to the reflection surface of each sound ray is such that each sound ray is completely reflected and The ultrasonic liquid ejection device according to any one of claims 13 to 16, wherein the maximum value of the difference in the amount of phase shift due to the reflection of the sound ray is in a range of approximately 40 ° or less. 19. The reflection surface of the ultrasonic focusing device is constituted by a solid member made of brass and is disposed in a liquid such as water or ink. When a unit of length is represented by [m], a coefficient is set. 17. The ultrasonic liquid ejecting apparatus according to claim 13, wherein the value of a is approximately 1.3 × 10 ³ [m ⁻¹ ] or more. 20. A reflection surface of the ultrasonic focusing device is constituted by a solid member made of zinc and is disposed in a liquid that is water or ink. When a unit of length is represented by [m], a coefficient is set. 17. The ultrasonic liquid ejecting apparatus according to claim 13, wherein the value of a is approximately 1 × 10 ³ [m ⁻¹ ] or more. 21. A reflecting surface of the ultrasonic focusing device is constituted by a solid member made of magnesium and is arranged in a liquid such as water or ink. When a unit of length is represented by [m], a coefficient is expressed by: The value of a is approximately 0.8 × 10 ³
The ultrasonic liquid ejection device according to any one of claims 13 to 16, wherein the value is not less than [m- ¹ ]. 22. A reflecting surface of the ultrasonic focusing device is constituted by a solid member made of aluminum and is arranged in a liquid such as water or ink. When a unit of length is represented by [m], a coefficient is defined as: The value of a is approximately 0.7 × 10 ³
The ultrasonic liquid ejection device according to any one of claims 13 to 16, wherein the value is not less than [m- ¹ ].