close

Вход

Забыли?

вход по аккаунту

?

DESCRIPTION JP2000152390

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2000152390
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
drip-proof ultrasonic transducer for transmitting and receiving ultrasonic frequency bands.
[0002]
2. Description of the Related Art A conventional drip-proof ultrasonic transducer will be
described with reference to FIG. First, in the figure, reference numeral 1 denotes a piezoelectric
element, and the piezoelectric element 1 is bonded to the inside of the bottom of a bottomed
cylindrical case 2 to constitute a unimorph vibrator. A filler 8 is injected so as to seal between the
electrode pattern-provided substrate 5 and the bottomed cylindrical case 2. Reference numeral 7
denotes lead wires, one of the lead wires 7 is soldered to the electrode terminal 6 b implanted in
the electrode pattern-provided substrate 5, and the other is soldered to the electrode surface of
the piezoelectric element 1. The electrode terminal 6 a and the electrode pattern 3 are
electrically connected by soldering, and the electrode pattern 3 and the bottomed cylindrical case
2 are bonded to each other through the conductive adhesive 10.
[0003]
SUMMARY OF THE INVENTION In the configuration of the conventional drip-proof ultrasonic
transducer, when the pulse burst wave as shown in FIG. 3 is applied to the piezoelectric element,
13-04-2019
1
the bottom of the bottomed cylindrical case vibrates, Sound waves are radiated into the air at the
same time, and vibration is also transmitted to the bottomed cylindrical case side surface and the
lead wire, and even after the applied voltage ends, a roaring sound remains in the bottomed
cylindrical case, and this roaring noise As a result, vibration remains inside the bottomed
cylindrical case, and the vibration reversely vibrates the piezoelectric element to output an
induced voltage. This output voltage becomes a reverberation signal, and there is a problem that
it is not possible to receive waves during the time when this reverberation signal is present. FIG.
4 is a diagram showing this reverberation wave, and T1 is the time of the reverberation
component. The present invention solves such a problem, and when the piezoelectric element is
driven by a pulse burst wave, the reverberation in the bottomed cylindrical case is remarkably
suppressed while the decrease in the reception level of the reflected wave is minimized. It is
intended to be shortened.
[0004]
[Means for Solving the Problems] In order to solve the problems as described above, the
ultrasonic transducer according to the present invention comprises a piezoelectric element
bonded to the inner surface of the bottom of a cylindrical case with a bottom and a unimorph
transducer. It is characterized in that a polyurethane foam with an expansion ratio of 25 to 100
times is enclosed in a compressed state so as to have a volume ratio of 50 to 90% for
reverberation absorption throughout the inner space of the bottomed cylindrical case. Do.
[0005]
DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with
reference to FIG.
FIG. 1 is a schematic structural cross-sectional view of an ultrasonic transducer according to an
embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a piezoelectric
element, and the piezoelectric element 1 is bonded to the inner surface of a bottom portion of a
bottomed cylindrical case 2 to constitute a unimorph vibrator. 11 is a polyurethane foam having
an expansion ratio of 25 to 100 times containing a large amount of air layer, and is enclosed in
the entire internal space of the bottomed cylindrical case 2 in a compressed state so as to have a
volume ratio of 50 to 90% . The polyurethane foam 11 has a hole for penetrating the lead wire
12a. Reference numeral 8 denotes a filler made of an elastic member such as silicone rubber,
which is injected so that the space between the substrate 13 and the bottomed cylindrical case 2
is sealed. The substrate 13 is provided with a hole for penetrating the lead wire 12a. One of the
lead wires 12 a is soldered to the electrode surface of the piezoelectric element 1. The lead wire
13-04-2019
2
12 b is electrically conducted via the bottomed cylindrical case 2 and the conductive adhesive
10. By compressing the polyurethane foam 11 with an expansion ratio of 25 to 100 times in a
state where it is compressed to a volume ratio of 50 to 90%, the reflected wave reception level is
reduced by enclosing the entire inside space of the bottomed cylindrical case 2 The reverberation
vibration of the piezoelectric element 1, the bottomed cylindrical case 2, the lead wire 12 a, and
the substrate 13 can be efficiently suppressed while being minimized. At this time, if the
polyurethane foam 11 is compressed and sealed to a state where the volume ratio is smaller than
50%, the reflected wave reception level is significantly reduced. In addition, if the volume ratio is
higher than 90%, the reverberation vibration can not be suppressed if it is sealed in a
compressed state, and there are problems in either case. Similarly, when the expansion ratio of
the polyurethane foam is smaller than 25 times or larger than 100 times, the reverberation
vibration can not be suppressed in either case, and there is a problem. As described above, by
sealing the polyurethane foam 11 with an expansion ratio of 25 to 100 times so that the volume
ratio is 50 to 90%, the entire inside space of the bottomed cylindrical case 2 is sealed, as shown
in FIG. When the pulse burst wave shown in 3 is applied to the piezoelectric element 1, it is
possible to extremely suppress the reverberation vibration generated when the applied voltage is
finished, while minimizing the decrease in the reflected wave reception level, as shown in FIG. As
shown, the reverberation time can be significantly reduced.
[0006]
As described above, according to the present invention, polyurethane foam having an expansion
ratio of 25 to 100 times is compressed to a volume ratio of 50 to 90% over the entire inner space
of the bottomed cylindrical case. When the pulse burst wave is applied to the piezoelectric
element, the reverberation time can be remarkably shortened while minimizing the decrease in
the reception level of the reflected wave, thereby maintaining a wide detection area. Short
distance detection is also possible.
13-04-2019
3
Документ
Категория
Без категории
Просмотров
0
Размер файла
10 Кб
Теги
description, jp2000152390
1/--страниц
Пожаловаться на содержимое документа