JPH10201768A - Ultrasonic treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve propagation efficiency by preventing cavitation in a propagation medium on account of a negative pressure wave from a shock wave. SOLUTION: An ultrasonic wave generating source 3 is constituted by gluing together shell-like first and second vibrators 1, 2 formed by piezoelectric ceramics. Then, a pulse controller 4, at the time of driving the first vibrator 1 so as to generate shock wave, drives the second vibrator 2 so that a positive pressure wave with the same amplitude is generated in the timing in which the first negative wave is generated from the shock wave. In addition, the second vibrator 2 is also driven so that the negative and positive. Waves each of the same amplitude are generated in the timing in which the second and onward positive and negative waves are generated from the shock wave. As a result, all extra waves other than the first positive wave from the shock wave can be cancelled, preventing the inconvenience of cavitation in a propagation medium, and enabling the propagation efficiency to be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic treatment apparatus for performing destructive treatment by irradiating an ultrasonic wave to a lesion such as a calculus or a tumor in a body.

[0002]

2. Description of the Related Art Conventionally, ultrasonic waves are radiated from outside the body using an ultrasonic generator such as an electromagnetic conversion method, a spark gap method, a piezoelectric conversion method, and a micro blast method, and focused on a treatment site such as a calculus or a malignant tumor in the body. There is known an ultrasonic treatment apparatus for treating a treatment site noninvasively without opening the abdomen.

[0003] More specifically, an ultrasonic treatment apparatus of the electromagnetic conversion type generates an ultrasonic wave by vibrating a metal film by an electromagnetic transducer. To generate ultrasonic waves. In addition, a piezoelectric conversion type ultrasonic treatment device generates ultrasonic waves by oscillating a piezoelectric element, and a micro blast type ultrasonic treatment device generates an ultrasonic wave by exploding a micro explosive in water. Things.

[0004] In any type of ultrasonic therapy apparatus, a large-amplitude vibration wave (ultrasonic wave) is generated a plurality of times in a short time, and this is directed a plurality of times toward a treatment object such as a human body, which is a propagation medium. Irradiation is performed over the treatment site.

[0005]

In such an ultrasonic treatment apparatus of each type, it is desirable to perform a destructive treatment such as a calculus mainly by the positive pressure wave of the first ultrasonic wave generated each time. However, in practice, the ultrasonic wave source continues the aftershoot after the generation of the first positive pressure wave from the irradiation of the ultrasonic wave to the irradiation of the next ultrasonic wave. In addition, ultrasonic waves including the subsequent pressure waves, for example, the first negative pressure wave and the second pressure wave, are applied each time. Therefore, when the ultrasonic wave propagated to the propagation medium in the body shifts from the positive pressure wave to the negative pressure wave, bubbles (cavitation) are generated in the propagation medium such as the human body, and the cavitation causes the ultrasonic wave which is subsequently irradiated to be transmitted. There is a problem that the propagation is inhibited and the therapeutic effect is reduced.

On the other hand, if an ultrasonic wave having a large amplitude is used, the therapeutic effect is improved, and the ultrasonic wave generating source may be driven at a high voltage. However, if the high-voltage driving is continued, there is a problem that the load on the ultrasonic generation source is increased and the life of the ultrasonic generation source is shortened.

Further, in order to perform optimal treatment, it is preferable to form a desired focused ultrasonic pressure distribution by changing the frequency in accordance with the size of the object to be treated.
In order to make this possible, a unique frequency is conventionally determined at the source, so unless a plurality of types of ultrasonic sources having different frequencies are provided, an appropriate sound pressure distribution cannot be selected, and the configuration is complicated. In addition, there is a problem that the cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can prevent the occurrence of cavitation in a propagation medium, and can obtain an ultrasonic wave having a large amplitude without driving an ultrasonic wave source at a high voltage. It is another object of the present invention to provide an ultrasonic treatment apparatus capable of selecting ultrasonic waves of a plurality of types of frequencies with an inexpensive and simple configuration.

[0009]

SUMMARY OF THE INVENTION An ultrasonic therapy apparatus according to the present invention is directed to an ultrasonic therapy apparatus which focuses an ultrasonic wave on a desired portion of a subject to perform a treatment in order to solve the above-mentioned problems. And a drive control means for driving and controlling the ultrasonic generation source so as to generate only a positive pressure wave among the ultrasonic waves generated by the ultrasonic generation source.

[0010] Cavitation in the propagation medium occurs when the ultrasonic wave transitions from a positive pressure wave to a negative pressure wave. For this reason, the drive control means drives and controls the ultrasonic generation source so that only the positive pressure wave is generated among the ultrasonic waves generated by the ultrasonic generation source, so that the irradiation of the next ultrasonic wave is performed from the irradiation of the ultrasonic wave. Only the positive pressure wave among the pressure waves generated before the operation can be propagated to the propagation medium. Therefore, it is possible to prevent cavitation from occurring in the propagation medium and the like,
The second and subsequent ultrasonic waves can be effectively propagated to the propagation medium to improve the therapeutic effect.

Next, in order to solve the above-mentioned problems, an ultrasonic therapy apparatus according to the present invention uses a plurality of transducers for generating ultrasonic waves of the same frequency, thereby geometrically transforming each ultrasonic wave from each transducer. It comprises an ultrasonic wave generating source formed so that the focal positions coincide with each other, and a drive control means for driving and controlling the respective vibrators substantially simultaneously when generating ultrasonic waves.

This makes it possible to generate a plurality of times of ultrasonic waves with the same drive voltage (the amplitude is approximately twice when there are two vibrators, and approximately three times when there are three vibrators). .), It is possible to obtain ultrasonic waves having a large amplitude without forcibly driving at a high voltage. Therefore, the life of the ultrasonic wave source can be extended, and the therapeutic effect can be improved.

Next, in order to solve the above-mentioned problems, the ultrasonic therapy apparatus according to the present invention employs a plurality of transducers each generating an ultrasonic wave having a different frequency. An ultrasonic generating source formed so that the focal points coincide with each other, and drive control means for driving and controlling a vibrator corresponding to a desired frequency when generating ultrasonic waves. This makes it possible to select ultrasonic waves of a plurality of types of frequencies with a simple configuration and at low cost.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an ultrasonic therapy apparatus according to the present invention will be described below in detail with reference to the drawings. First, the ultrasonic therapy apparatus according to the first embodiment of the present invention includes a first transducer 1 as shown in FIG.
And a spherical-shell-shaped ultrasonic generating source 3 formed by bonding the second vibrator 2 in parallel so that the geometrical focal points substantially coincide with each other, and a pulse controller for driving and controlling each of the vibrators 1 and 2 4 and a source driving unit 5 having first and second drivers 6 and 7 for driving the vibrators 1 and 2 according to the driving pulse from the pulse controller 4.

The first transducer 1 and the second transducer 1 of the ultrasonic wave source 3
The vibrator 2 is made of, for example, a piezoelectric vibrating member such as zirconate / lead titanate or a piezoelectric ceramic formed by mixing the zirconate / lead titanate with polyvinylidene fluoride. Natural frequency (resonance frequency) of piezoelectric vibration member
Is determined by the “thickness of the member”. In this case, the vibrators 1 and 2 are formed to have substantially the same thickness.

That is, by setting the resonance frequencies of the first vibrator 1 and the second vibrator 2 to be the same, both vibrators 1 and 2 can be driven under the same conditions, and the system can be simplified. be able to. Further, by joining the first vibrator 1 and the second vibrator 2 in parallel so that the focal points coincide, an effect of suppressing the generation of a negative pressure wave near the focal point is produced.

Each of the vibrators 1 and 2 is brought into close contact with each other so that the movement of one vibrator is linked to the movement of the other vibrator. However, the condition is satisfied. For example, it can be changed according to design, specifications, etc., such as laminating both via an incompressible member.

Next, the operation of the ultrasonic therapy apparatus according to the first embodiment having such a configuration will be described. In the ultrasonic therapy apparatus, when the calculus crushing treatment is performed, the pulse controller 4 controls the driving of the first vibrator 1 via the first driver 6 and, as shown by the oblique lines in FIG.
The driving of the second vibrator 2 is controlled via the second driver 7 so as to cancel the negative pressure wave of the wave and the after wave of the second wave and thereafter.

FIG. 2 is a diagram showing the transition of the motion of each of the vibrators 1 and 2 in eliminating the after-vibration of the first vibrator 1, and specifically operates as follows. First, st in FIG.
ep1 is a signal from the pulse controller 4 to the first driver 6
In this state, no drive pulse is output. In this state, when a driving pulse from the pulse controller 4 is supplied to the first driver 6, the first driver 6 supplies a voltage to the first vibrator 1. The first vibrator 1 expands when a voltage is obtained, and generates a positive pressure ultrasonic wave (step).
2). Subsequently, the first vibrator 1 starts contracting (s
step3).

Here, the first vibrator 1 generates a negative pressure ultrasonic wave when contracted from the thickness before the voltage is supplied, so that the thickness of the first vibrator 1 before the voltage is supplied is reduced. The second vibrator 2 is driven at the timing when the thickness becomes thick. The driving of the second vibrator 2 is performed by supplying a voltage from the second driver 7. When the voltage is supplied, the second vibrator 2 expands (vibrates to the positive pressure side) by an amount that the first vibrator 1 contracts before the voltage is supplied (step 4). In this manner, the surface on the focal point side of the first vibrator 1 is prevented from contracting as compared to before the voltage is supplied (step 5).

After suppressing the after vibration of the first vibrator 1, the second vibrator 2 contracts. At this time, if the first vibrator 1 is expanded (step 6), First vibrator 1
The degree of displacement between the first vibrator 1 and the second vibrator 2 does not become smaller than before the voltage is first applied to the first vibrator 1.

Thus, the generation of a negative pressure wave due to the after vibration (shrinkage) of the first vibrator 1 can be suppressed. This operation will be described with reference to FIG. FIG. 3 is a diagram for explaining the principle for canceling the after wave after the second wave. FIG.
FIG. 3A is a diagram illustrating an ultrasonic wave generated from the first vibrator 1 when the second vibrator 2 is not driven, and FIG.
FIG. 3B is a diagram showing ultrasonic waves generated from the second vibrator 2 by driving only the second vibrator 2, and FIG.
FIG. 5 is a diagram showing ultrasonic waves generated from the first vibrator 1 when the second vibrator 2 is driven at a predetermined timing after the driving of the vibrator 1.

First, when the first vibrator 1 is driven, FIG.
As shown in (a), the second and subsequent pressure waves are generated by the after vibration of the first vibrator 1 following the first positive and negative pressure waves. Therefore, the pulse controller 4
Controls the driving of the second vibrator 2 so as to generate a positive pressure wave having the same amplitude as the first negative pressure wave as shown in FIG. 3B. Further, at the timing when the second positive pressure wave and the negative pressure wave due to the overshoot of the first vibrator 1 are generated, the second vibrator 2 is caused to generate the negative pressure wave and the positive pressure wave having the same amplitude. Drive control.

The driving timing of the second vibrator 2 is as follows.
Determined based on experimental results and stored in the pulse controller. As a result, it is possible to prevent generation of all of the first negative pressure wave and the second and subsequent after-waves that would be generated when the first vibrator 1 is driven.
As shown in (c), only the first positive pressure wave can be applied to the calculus.

For this reason, it is possible to prevent the occurrence of cavitation when the ultrasonic wave transitions from the positive pressure wave to the negative pressure wave, and to prevent the propagation of the ultrasonic wave from being hindered by the cavitation even if the ultrasonic wave is continuously irradiated. Only the first positive pressure wave of each irradiation can be applied to the calculus. Therefore, the effect of the calculus crushing treatment can be improved.

Next, in the above description of the first embodiment, all of the first negative pressure wave and the second and subsequent residual waves are cancelled. Alternatively, only the second and subsequent positive pressure waves may be generated.

As described above, the cavitation is generated when the ultrasonic wave changes from the positive pressure wave to the negative pressure wave.
However, when the first vibrator 1 is driven, the second vibrator 2 is generated such that a positive pressure wave having the same amplitude is generated at a timing when a negative pressure wave is generated among the ultrasonic waves shown in FIG. Drive.

The driving timing of the second vibrator 2 is as follows.
It is preliminarily calculated by an experiment based on the transition of the displacement of the first vibrator 1. As a result, the second and subsequent positive pressure waves including the first positive pressure wave are propagated. However, since this ultrasonic wave does not shift to a negative pressure wave, it is necessary to prevent the occurrence of cavitation. Thus, the same effects as those of the ultrasonic therapy apparatus according to the first embodiment can be obtained.

Next, an ultrasonic therapy apparatus according to a second embodiment of the present invention will be described. The ultrasonic therapy apparatus according to the second embodiment is the same as the ultrasonic therapy apparatus according to the first embodiment except for the drive control of each of the vibrators 1 and 2 at the time of generating an ultrasonic wave described below. Since the ultrasonic therapy apparatus is the same as the ultrasound therapy apparatus, only this point will be described in the description of the ultrasonic therapy apparatus according to the second embodiment, and detailed description of other parts will be omitted.

First, FIG. 4 shows the movement of each of the oscillators 1 and 2 when the first oscillator 1 and the second oscillator 2 are simultaneously driven in the ultrasonic therapy apparatus according to the second embodiment. FIG. 5 is a diagram showing ultrasonic waves generated when the transducers 1 and 2 are simultaneously driven.

Step 11 in FIG. 4 is the first driver 6
And a state in which no voltage is supplied from the second driver 7 to each of the vibrators 1 and 2. From this state, the pulse controller 4 supplies drive pulses to the first driver 6 and the second driver 7 substantially simultaneously.

First driver 6 and second driver 7
Supplies a voltage to each of the vibrators 1 and 2 when the drive pulse is supplied. Thereby, each of the vibrators 1 and 2
Are supplied almost simultaneously.

Each of the vibrators 1 and 2 expands when a voltage is supplied, and generates ultrasonic waves of positive pressure (step 12). Subsequently, each of the vibrators 1 and 2 starts contracting (step 1).
3). When each of the vibrators 1 and 2 is completely contracted (ste)
p14), expansion and contraction are repeated again as aftershocks (st
ep15, 16), and gradually converges to a state where no voltage is supplied (step 17).

Each of the vibrators 1 and 2 has the same natural frequency. For this reason, by driving each of the transducers 1 and 2 at the same time, as shown in FIG. 5, the ultrasonic generator 3 as a whole has twice the amplitude, despite the use of a voltage for driving one transducer. Ultrasonic waves can be generated.

Therefore, the amplitude of the ultrasonic wave to be irradiated can be increased without driving the ultrasonic wave source 3 at a high voltage, thereby improving the therapeutic effect without imposing an excessive burden on the ultrasonic wave source 3. Can be achieved.

In this case, the pulse controller 4
After driving the transducers 1 and 2 at substantially the same time, only the positive pressure wave is generated, or only the first positive pressure wave is generated, similarly to the ultrasonic therapy apparatus according to the above-described first embodiment. The driving control of the second vibrator 2 may be performed in such a manner. Thus, the same effects as those of the ultrasonic therapy apparatus according to the above-described first embodiment can be obtained, such as the occurrence of cavitation can be prevented.

Next, an ultrasonic therapy apparatus according to a third embodiment of the present invention will be described. In the ultrasonic therapy apparatuses according to the first and second embodiments, the vibrators 1 and 2 have the same natural frequency, but the third and fourth vibrators have the same natural frequency.
In the ultrasonic therapy apparatus according to the embodiment, the ultrasonic generator 3 is formed by two vibrators having different natural frequencies, and each vibrator is independently driven according to the ultrasonic wave having a desired frequency. It is like that.

The ultrasonic therapy apparatus according to the third embodiment has the same configuration as the ultrasonic therapy apparatus according to each of the above-described embodiments except for the above. The same reference numerals are given to the portions showing the same operation as the ultrasonic therapy apparatus, and the detailed description thereof will be omitted.

FIG. 6 is a block diagram showing a configuration of an ultrasonic therapy apparatus according to the third embodiment. This figure 6
In the ultrasonic therapy apparatus according to the third embodiment,
The ultrasonic generator 3 includes a first vibrator 31 for generating a high-frequency ultrasonic wave and a second vibrator for generating a low-frequency ultrasonic wave having a different natural frequency with respect to the first vibrator 31. Child 32
Are formed in parallel with each other so that the geometrical focal points substantially coincide with each other, and the pulse controller 4 operates the first vibrator 31 or the second vibrator according to the ultrasonic frequency specified by the operator. The drive of the child 32 is controlled.

The frequency of the ultrasonic wave generated from the vibrator is determined by the thickness of the vibrator, the ceramic material, the radius of the vibrator, and the like. FIG. 7A is a diagram showing a transition of the movement of each of the transducers 31 and 32 when a low-frequency ultrasonic wave is generated.

Step 21 in FIG. 7A is a state in which no voltage is supplied from the first driver 6 and the second driver 7 to each of the oscillators 31 and 32. When generation of low-frequency ultrasonic waves is selected by the operator, the pulse controller 4 supplies a driving pulse to the second driver 7.

When supplied with the drive pulse, the second driver 7 is a second oscillator, which is a vibrator for generating low-frequency ultrasonic waves.
Is supplied to the vibrator 32. The second vibrator 32
When a voltage is supplied, it expands to generate a positive pressure low frequency ultrasonic wave (step 22). Subsequently, the second vibrator 32
Starts contraction (step 23). When the second vibrator 32 has completely contracted (step 24), expansion and contraction are repeated again as aftershocks (steps 25 and 26), and the state gradually converges to a state where no voltage is supplied (step 24).
27). Thereby, a low frequency ultrasonic wave can be generated.

In this case, the first vibrator 31 to which no voltage is supplied does not expand and contract, but vibrates as the second vibrator 32 expands and contracts. Next, FIG. 7B is a diagram showing a transition of the movement of each of the transducers 31 and 32 when generating a high-frequency ultrasonic wave.

Step 31 in FIG. 7B is a state in which no voltage is supplied from the first driver 6 and the second driver 7 to each of the vibrators 31 and 32. When generation of high-frequency ultrasonic waves is selected by the operator, the pulse controller 4 supplies a driving pulse to the first driver 6.

When this driving pulse is supplied, the first driver 6 is a first driver, which is a vibrator for generating high-frequency ultrasonic waves.
Is supplied to the vibrator 31. The first vibrator 31
When the voltage is supplied, it expands and generates a positive pressure low frequency ultrasonic wave (step 32). Subsequently, the first vibrator 31
Starts contraction (step 33). When the first oscillator 31 has completely contracted (step 34), expansion and contraction are repeated again as aftershocks (steps 35 and 36), and the voltage gradually converges to a state where no voltage is supplied (step 34).
37).

In this case, the second vibrator 32 to which no voltage is supplied does not expand and contract, but vibrates as the first vibrator 31 expands and contracts. As described above, the ultrasonic therapy apparatus according to the third embodiment includes the first vibrator 31 for high frequency generation and the second vibrator 32 for low frequency generation. By driving the vibrators 31 and 32, an ultrasonic wave having a desired frequency can be generated with a simple configuration and at low cost, and optimal crushing treatment can be performed according to the size of a calculus or the like.

In this case, after the pulse controller 4 drives the oscillators 31 and 32 having the desired frequency, the negative pressure wave is prevented from being generated as described above, or the second and subsequent waves are generated together with the negative pressure wave. The driving of another vibrator may be controlled so as not to generate a positive pressure wave. Thus, the same effects as those of the ultrasonic therapy apparatus according to the above-described first embodiment can be obtained, such as the occurrence of cavitation can be prevented.

In the description of the third embodiment,
Two types of vibrators 31, 32 having different natural frequencies
Is used to form the ultrasonic generating source 3, but it may be formed by three or four types of vibrators having different natural frequencies. Thereby, three or four types of ultrasonic waves can be selected, and more optimal crushing treatment can be performed.

Next, a modified example of the ultrasonic therapy apparatus according to the first to third embodiments will be described. That is, in the ultrasonic therapy apparatuses according to the above-described first to third embodiments, the single spherical and shell-shaped first and second transducers 1 and 2 (3
1, 32) is used, but the ultrasonic therapy apparatus according to this modified example has a first vibrator 1 (31) and a flat plate-like or rectangular disk-shaped vibrator 1 (31) as shown in FIG. The second vibrators 2 (32) are bonded in parallel, and a plurality of the second vibrators 2 (32) are arranged inside a support plate 33 having a spherical shell shape as a whole.

In this case, the pulse controller 4 drives and controls the vibrators 1 and 2 (31, 32) as described above in accordance with the purpose of generating an ultrasonic wave or canceling a negative pressure wave. Thereby, the same effects as those of the ultrasonic therapy apparatuses according to the above-described first to third embodiments can be obtained.

In addition, by forming a plurality of piezoelectric vibrating members into a concave shape as a whole, the thickness of the vibrator can be easily formed to a desired thickness, so that the vibrator can be formed with high accuracy. As a result, the production yield can be improved.

Each of the vibrators 1 and 2 in this modification example
Needless to say, the shape of (31, 32) can be formed in a desired shape according to the design, etc., other than the rectangular plate shape or the disc shape.

Next, an ultrasonic treatment apparatus according to a fourth embodiment of the present invention will be described. The ultrasonic therapy apparatus according to each of the above embodiments is a piezoelectric conversion type ultrasound therapy apparatus. However, the ultrasonic therapy apparatus according to the fourth embodiment and a fifth embodiment to be described later. The ultrasonic therapy apparatus according to the above is configured to generate ultrasonic waves by a piezoelectric conversion method, and to cancel the after-effects by a metal film.

The ultrasonic therapy apparatus according to the fourth embodiment is characterized by the configuration of the ultrasonic wave generating source 3, and the configuration of the other parts is the same as the ultrasonic therapy apparatus according to each of the above-described embodiments. Therefore, in this description, the configuration and operation of the ultrasonic wave generating source 3 will be referred to, and the description of the other parts will be omitted.

That is, the ultrasonic generating source 3 provided in the ultrasonic therapy apparatus according to the fourth embodiment has the configuration shown in FIG.
As shown in FIG. 7, a support plate 35, a coil 36 supported by the support plate 35, a first vibrator 37 for generating ultrasonic waves formed by piezoelectric ceramics, an insulating film 38, and a metal film are formed. And a second vibrator 39 for canceling the after-wash.

In FIG. 9, the support plate 35 to the second vibrator 39 are shown separated from each other for convenience of explanation, but actually the support plate 35 to the second vibrator 39 are The ultrasonic sources 3 are formed by bonding.

The whole of the ultrasonic generator 3 is formed in a spherical shell shape so that the generated ultrasonic waves can be focused at one point. Further, the first vibrator 37 is connected to the first driver 6 in the source driving unit 5, and the coil 36 is connected to the second driver 7. Then, as described below, when the first vibrator 37 is driven to generate ultrasonic waves, energy of a predetermined voltage is discharged to the coil 36, thereby indirectly connecting the second vibrator 39. By driving, the residual wave caused by driving the first vibrator 37 is canceled.

More specifically, when an ultrasonic wave is generated by the ultrasonic treatment apparatus according to the fourth embodiment, the pulse controller 4 is connected to the first driver 6 via the first driver 6 to form a first piezoelectric ceramic. A predetermined voltage is applied to the vibrator 37. Thereby, the first vibrator 37 is driven to generate an ultrasonic wave. This ultrasonic wave is applied to the calculus via the insulating film 38 and the second vibrator 39. Thereby, the calculus in the human body can be crushed.

On the other hand, when the first vibrator 37 is driven in this manner, the pulse controller 4 generates the first negative pressure wave of the ultrasonic wave at the timing when the first negative pressure wave is generated as described with reference to FIG. Energy of a voltage corresponding to the first negative pressure wave is discharged to the coil 36 so as to generate a positive pressure wave having the same amplitude. Also, at the timing when the second positive pressure wave and negative pressure wave due to the after vibration of the first vibrator 37 are generated, the coils 36 are generated so as to generate negative pressure waves and positive pressure waves having the same amplitude as these.
The energy of the voltage corresponding to the aftermath is discharged. Then, such an operation is repeatedly performed by the amount of the residual wave generated by driving the first vibrator 37.

When energy of a voltage corresponding to the after wave or the like is discharged to the coil 36, a magnetic field corresponding to the energy is generated, and the magnetic field causes the second metal film, which is a metal film provided via the insulating film 38, to be formed. An eddy current is induced on the vibrator 39.
Since the direction of the magnetic field generated by the eddy current is opposite to the direction of the magnetic field generated by the coil 36, a repulsive force is generated between the coil 36 and the metal film (second vibrator 39), and the metal film is Displaces momentarily.

The pulse controller 4 discharges the energy of the voltage corresponding to the after-wave to the coil 36 so that the displacement of the metal film cancels out the negative wave of the first ultrasonic wave and the after-wave of the second and subsequent waves. I do.

As a result, all of the first negative pressure wave and the second and subsequent after waves, which would be generated when the first vibrator 37 is driven, can be canceled out. As in the ultrasonic treatment device according to the embodiment, the occurrence of cavitation can be prevented, and the effect of the calculus crushing treatment can be improved.

The pulse controller 4 cancels all the negative pressure wave of the first wave and the after wave of the second wave.
The discharge control of the energy of the predetermined voltage to the coil 36 is performed. However, the discharge control of the energy of the predetermined voltage to the coil 36 is performed so as to cancel only the negative pressure waves after the first wave and the second wave. You may. Even in this case, the occurrence of cavitation can be prevented, and the effect of the calculus crushing treatment can be improved.

In this embodiment, the first vibrator 37
Since at least one of the second vibrator 39 and the second vibrator 39 is made of a metal film instead of piezoelectric ceramics, the durability can be improved.

Next, an ultrasonic therapy apparatus according to a fifth embodiment of the present invention will be described. The ultrasonic treatment apparatus according to the above-described fourth embodiment has the entire ultrasonic generation source 3 formed in a spherical shell shape. However, the ultrasonic treatment apparatus according to the fifth embodiment has Each part is formed in a flat plate shape, and the generated ultrasonic waves are focused using an acoustic lens.

Since the ultrasonic therapy apparatus according to the fifth embodiment is otherwise the same as the ultrasonic therapy apparatus according to the fourth embodiment, the description of the ultrasonic therapy apparatus will be omitted in this description. The configuration and operation of the source 3 will be referred to, and the description of the other parts will be omitted.

That is, the ultrasonic generating source 3 provided in the ultrasonic therapy apparatus according to the fifth embodiment has the configuration shown in FIG.
As shown in FIG. 5, a flat support plate 41, a coil 42 supported thereby, a first vibrator 43 for generating ultrasonic waves formed by piezoelectric ceramics, an insulating film 44, and a metal film are formed. And a second vibrator 45 for canceling the residual wave, and an acoustic lens 46 for converging the ultrasonic wave is provided on the ultrasonic wave generation side.

The first vibrator 43 is connected to the first driver 6 in the source driving unit 5, and the coil 42 is connected to the second driver 7, and drives the first vibrator 43. When an ultrasonic wave is generated, the energy of a predetermined voltage is discharged to the coil 42, the eddy current causes the second vibrator 45 to be indirectly driven, and the first vibrator 43 is driven to generate an after-wave. Is to be canceled.

Specifically, when an ultrasonic wave is generated by the ultrasonic therapy apparatus according to the fifth embodiment, the pulse controller 4 is connected to the first driver 6 via the first driver 6 to perform the first operation. A predetermined voltage is applied to the vibrator 43. Thereby, the first vibrator 43 is driven to generate an ultrasonic wave. The ultrasonic waves are focused by the acoustic lens 46 via the insulating film 44 and the second vibrator 45 and are applied to the calculus. Thereby, the calculus in the human body can be crushed.

On the other hand, when the first vibrator 43 is driven in this way, the pulse controller 4 controls the coil 36 so as to cancel the negative pressure wave of the first ultrasonic wave and the after wave of the second ultrasonic wave. Discharge control of voltage energy.

As a result, cavitation can be prevented as in the case of the ultrasonic treatment apparatus according to the fourth embodiment, and the effect of the calculus crushing treatment can be improved.

In this embodiment, the first vibrator 4
Forming the 3 and the like in a plate shape facilitates the manufacture of the ultrasonic wave source 3 and the like. Lastly, the description of each of the above embodiments is an example of the present invention, and various changes can be made according to the design and the like without departing from the technical idea according to the present invention. Of course.

For example, in the description of the fourth and fifth embodiments, the first vibrators 37 and 43 and the second vibrators 39 and 4
Although an example has been described in which one of the elements 5 is formed of a metal film, both the vibrators 37, 39, 43, and 45 may be formed of a metal film.

In the description of the fourth and fifth embodiments, the coils 36 and 42, the piezoelectric ceramics 37 and 43, the insulating films 38 and 44, and the metal films 39 and 45 are laminated in this order to form the ultrasonic wave source 3 However, since it is sufficient that two types of vibrators are located with the insulating films 38 and 44 interposed therebetween, for example, the coils 36 and 42, the metal films 39 and 45, and the insulating films 38 and 44 And the piezoelectric ceramics 37 and 43 may be laminated in this order.

[0075]

The ultrasonic treatment apparatus according to the present invention prevents the occurrence of cavitation in the propagation medium and effectively propagates the ultrasonic waves after the second irradiation to the propagation medium to improve the treatment effect. Can be.

Also, an ultrasonic wave having a large amplitude can be obtained without driving the ultrasonic wave source at a high voltage. For this reason, it is possible to extend the life of the ultrasonic generation source. Further, it is possible to generate ultrasonic waves of a plurality of kinds of frequencies with an inexpensive and simple configuration. Therefore, it is possible to select the frequency of the ultrasonic wave according to the size of the treatment target.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a main part of an ultrasonic treatment apparatus according to a first embodiment to which an ultrasonic treatment apparatus according to the present invention is applied.

FIG. 2 is a diagram for explaining a drive for canceling aftermath in the ultrasonic therapy apparatus according to the first embodiment.

FIG. 3 is a diagram for explaining how the aftermath is canceled out in the ultrasonic therapy apparatus according to the first embodiment.

FIG. 4 is a diagram illustrating a state in which respective transducers are simultaneously driven in an ultrasonic therapy apparatus according to a second embodiment of the present invention.

FIG. 5 is a view showing a shock wave generated by simultaneously driving the respective vibrators.

FIG. 6 is a diagram showing a configuration of a main part of an ultrasonic treatment apparatus according to a third embodiment to which the ultrasonic treatment apparatus according to the present invention is applied.

FIG. 7 is a diagram showing a state in which respective transducers provided in the ultrasonic therapy apparatus according to the third embodiment are separately driven in accordance with a desired sound pressure.

FIG. 8 is a view for explaining a modification of the main part of the ultrasonic therapy apparatus according to the first to third embodiments.

FIG. 9 is a diagram showing a configuration of a main part of an ultrasonic treatment apparatus according to a fourth embodiment to which the ultrasonic treatment apparatus according to the present invention is applied.

FIG. 10 shows a fifth embodiment to which the ultrasonic therapy apparatus according to the present invention is applied.
It is a figure showing composition of an important section of an ultrasonic therapy device concerning an embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st vibrator, 2 ... 2nd vibrator, 3 ... Ultrasonic wave generator 4 ... Pulse controller, 5 ... Generator drive part, 6 ... 1st
Driver 7: Second driver, 11: Applicator, 12: Ultrasonic probe

Claims (7)

[Claims] 1. An ultrasonic treatment apparatus for performing treatment by focusing ultrasonic waves on a desired site of a subject, comprising: an ultrasonic generator for generating ultrasonic waves; and an ultrasonic wave generated by the ultrasonic generator. And a drive control means for controlling the drive of the ultrasonic generation source so as to generate only a positive pressure wave. 2. The ultrasonic wave source according to claim 1, wherein said ultrasonic waves are generated so that geometrical focal points of generated ultrasonic waves coincide with each other.
And the second vibrator, and the drive control means is configured to generate the ultrasonic wave by the first vibrator.
When the first vibrator is driven and controlled, the second vibrator generates the positive pressure wave at the timing when the first vibrator generates the negative pressure wave.
2. The ultrasonic therapy apparatus according to claim 1, wherein the vibrator is driven and controlled. 3. The ultrasonic generating source includes first and second vibrators and an acoustic lens that focuses the generated ultrasonic wave at one point, and the drive control unit generates the ultrasonic wave. So the first
When the first vibrator is driven and controlled, the second vibrator generates the positive pressure wave at the timing when the first vibrator generates the negative pressure wave.
2. The ultrasonic therapy apparatus according to claim 1, wherein the vibrator is driven and controlled. 4. The drive control means according to claim 1, wherein when the first vibrator is driven to generate an ultrasonic wave, the first vibrator generates a positive pressure wave at a timing at which the first vibrator generates a negative pressure wave. And drive-controlling the second vibrator so that the first vibrator generates a negative pressure wave at a timing at which the first vibrator generates the second and subsequent positive pressure waves. The ultrasonic treatment apparatus according to claim 2 or 3, wherein: 5. An ultrasonic generating source formed by a plurality of transducers for generating ultrasonic waves of the same frequency so that the geometrical focal position of each ultrasonic wave from each transducer coincides with each other. An ultrasonic therapy apparatus having drive control means for driving and controlling each of the vibrators substantially simultaneously when it occurs. 6. An ultrasonic generating source formed by a plurality of transducers each generating an ultrasonic wave having a different frequency so that a geometrical focal position of each ultrasonic wave from each transducer coincides with each other. And a drive control means for driving and controlling the vibrator corresponding to a desired frequency when generating the ultrasonic wave. 7. The ultrasonic generator according to claim 5, wherein the ultrasonic generator comprises a first vibrator and a second vibrator for generating ultrasonic waves having different frequencies. Ultrasound therapy equipment.