JPH07265315A - Ultrasonic probe - Google Patents

Abstract

PURPOSE:To obtain an ultrasonic probe measuring the operation temp. of a piezoelectric vibrator within a real time to keep reliability or quality and high in the safety against a low temp. burn by connecting a heat conductor to the drive electrode of the piezoelectric vibrator and bonding a temp. responsive element to a conductor to detect the operation temp. of the piezoelectric vibrator. CONSTITUTION:An ultrasonic probe is constituted by arranging a piezoelectric element 2 having a packing material 4 inserted to the gap thereof, having a reference electrode and signal electrodes 3a, 3b arranged on both main surfaces thereof and having acoustic matching layers 5a, 5b and acoustic lenses arranged on the front surface thereof on a backing material 1. A flexible substrate 7 leading out the signal electrode 3b in a zigzag pattern is connected to the rear surface of the piezoelectric element 2 and silver foil 13 is bonded to one end of the piezoelectric element 2 to be led out. Further, a thermistor 11 is fixed to the silver foil 13 and a lead wire 12 is led out to the outside. By this constitution, the heating temp. due to the piezoelectric element 2 can be detected within a real time through the silver foil 13 and, when operation temp. becomes a prescribed value or more, the application of a high voltage pulse from a diagnostic apparatus is stopped to suppress the generation of heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field of application of an ultrasonic probe, and in particular, it detects an operating temperature of a piezoelectric vibrator for generating an ultrasonic wave to prevent characteristic deterioration and enhances safety. Regarding a sound wave probe.

[0002]

BACKGROUND OF THE INVENTION An ultrasonic probe is useful as a transmitting / receiving unit in an ultrasonic diagnostic apparatus for medical use, etc., using a piezoelectric vibrator as a source of ultrasonic waves. In such a device, a high-voltage pulse is applied to the piezoelectric vibrator, and ultrasonic waves centered on a resonance frequency determined by the thickness thereof are transmitted and received. In recent years, it has been pointed out that safety problems such as deterioration of characteristics of an ultrasonic probe and low-temperature burn caused by heat from a piezoelectric vibrator generated when energy is converted from electricity to machinery.

[0003]

2. Description of the Related Art FIG. 2 is an ultrasonic probe diagram for explaining a conventional example of this kind. FIG. 2 (a) is a front view and FIG. 2 (b) is a side view. The ultrasonic probe is PZT on the backing material 1.
Piezoelectric elements 2 made of (lead zirconate titanate) are arranged in the width direction. Driving electrodes 3 (ab) are provided on both main surfaces of the piezoelectric element 2, and a reinforcing filler 4 is embedded between the piezoelectric elements 2. The front drive electrode 3a is used as a reference potential electrode, and the rear drive electrode 3b is used as a signal electrode.
Then, on the front surface of the piezoelectric element 2, a two-layer acoustic matching layer 5 (ab) is provided to measure acoustic impedance matching with a living body and improve ultrasonic wave propagation efficiency. Further, an acoustic lens 6 that is convex in the length direction of the piezoelectric element 2 is provided. Flexible substrates 7 are provided on both sides of the rear surface of the piezoelectric element 2, and the signal electrodes 8 lead out the signal electrodes 3b alternately (staggeredly). The reference potential electrode 3a
In order to maintain the symmetry of the ultrasonic wave, is led out on both sides of the piezoelectric element 2 by being commonly connected by the lead wire 9.
Further, the backing material 1 is fixed to the base 10. Then, in such a device, for example, a high-voltage pulse is applied to each piezoelectric element 2 through a delay circuit (not shown) to perform sector drive.

[0004]

However, in the ultrasonic probe having such a structure, heat is generated in each piezoelectric element 2 by continuously applying a high voltage pulse.
Then, these heats increase the surface temperature of the piezoelectric element and particularly violate the interface with the acoustic matching layer 5. Therefore, there is a problem that acoustic characteristics are deteriorated due to breakage or peeling of the acoustic matching layer 5 and the like, and reliability and quality are deteriorated, and safety such as low-temperature burn is impaired.

For this reason, conventionally, as shown in FIG. 3, a temperature sensitive element such as the thermistor 11 is embedded in the backing material 1 and its lead wire 12 is led to the outside. Then, the heat generation temperature (operating temperature) of the piezoelectric element 2 is detected from the resistance value of the thermistor 11, and when it exceeds a specified value, the operation from the diagnostic device is interrupted to protect the ultrasonic probe. I was doing. However, in such a device, since the thermistor 11 is embedded in the backing material 1 and is distant from the backing material 1, the operating temperature of the piezoelectric element 2 cannot be measured in real time, and the reliability and quality are deteriorated as described above, and low temperature burns, etc. There was a problem that impaired the safety of. It is also possible to embed the thermistor 11 in a portion close to the piezoelectric element 2 and measure in real time, but in this case,
It cannot be used because the effect of the backing material 1 is impaired.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ultrasonic probe which measures the operating temperature of a piezoelectric vibrator in real time, maintains reliability and quality, and is highly safe against low-temperature burns and the like. To do.

[0007]

The present invention is to solve the problem that a conductor is connected to a drive electrode of a piezoelectric vibrator, a temperature sensitive element is attached to the conductor, and the operating temperature of the piezoelectric vibrator is detected. Hereinafter, one embodiment of the present invention will be described together with its operation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining an embodiment of the present invention.
The figure (a) is a partial view of an ultrasonic probe, and the figure (b) is a side view. It should be noted that the same parts as those in the previous conventional example are designated by the same reference numerals, and the description thereof will be simplified. Similar to the prior art example, the ultrasonic probe has the reinforcing filler 4 provided in the gap, has the reference potential and signal electrodes 3 (ab) on both main surfaces, and has the acoustic matching layer 5 on the front surface. And piezoelectric element 2 provided with acoustic lens 6
Are arranged on the backing material 1. Further, a flexible substrate 7 that leads out the signal electrodes 3b in a staggered manner is connected to the rear surface of each piezoelectric element 2. In this embodiment, the silver foil 13 is joined to one end of the piezoelectric element 2 and led out. Further, the thermistor 11 is fixed on the silver foil 13, and the lead wire 12
To the outside. The other end of the piezoelectric element 2 is commonly connected by a lead wire 9.

With such a structure, the heat generation temperature (operating temperature) of the piezoelectric element 2 can be detected in real time through the silver foil 13. Therefore, when the operating temperature becomes equal to or higher than the specified value, the application of the high voltage pulse from the diagnostic device can be interrupted to suppress the heat generation. From such a thing,
The destruction of the acoustic matching layer 5 can be prevented, and the reliability and quality of the ultrasonic probe and the safety such as low temperature burns can be maintained. Also,
In this embodiment, since the silver foil 13 is provided at one end of the piezoelectric element 2 and the lead wire 9 is provided at the other end, the symmetry of ultrasonic waves can be maintained.

[0010]

[Other Matters] In the above embodiment, one thermistor 11 is attached to the silver foil 13, but the thermistor 11 may be attached corresponding to each piezoelectric element 2. In this case, the silver foil 13 may be separately divided for each piezoelectric element 2. Also, the piezoelectric element 2 is divided into a plurality of groups, and the silver foil 1 is divided into groups.
3 may be provided and the thermistor 11 may be attached to each. Further, the material is not limited to the silver foil 13, and any material having good thermal conductivity (heat conductor) may be used. Further, the driving is not limited to the sector driving, and another driving method or a single plate may be used. Although the temperature sensitive element is the thermistor 11, it is needless to say that it may be a posistor or one using a temperature current characteristic of a diode or the like, and may be appropriately changed without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a diagram of an ultrasonic probe for explaining an embodiment of the present invention, in which FIG. 1 (a) is a partial view of the ultrasonic probe and FIG. 1 (b).
Is a side view.

FIG. 2 is a diagram for explaining a conventional example, in which FIG. 2 (a) is a front view and FIG. 2 (b) is a side view.

FIG. 3 is a partial front sectional view for explaining a conventional example.

[Explanation of symbols]

1 backing material, 2 piezoelectric vibrator, 3 electrodes, 4 filling material, 5 acoustic matching layer, 6 acoustic lens, 7 flexible substrate, 8 signal line, 9, 12 lead wire, 10 base, 11 thermistor, 13 silver foil.

Claims (1)

[Claims] 1. An ultrasonic probe comprising a piezoelectric vibrator which is a source of ultrasonic waves, wherein a thermal conductor is connected to a drive electrode of the piezoelectric vibrator, and a temperature sensitive element is attached to the conductor. An ultrasonic probe characterized by detecting an operating temperature of the piezoelectric vibrator.