вход по аккаунту



код для вставкиСкачать
Patent Translate
Powered by EPO and Google
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.
■ Tension measurement device for vibrating membrane ■ Japanese Patent Application No. 4565316 [phase] intercondyle 45 (1970) July 24 @ inventor Tokohira Hirano Kobayashi-ku
Kohoku-ku Tsunashima-cho Matsushita Electric Industrial Co., Ltd. Kadoma City Oji Mon Makoto
10060s buried patent attorney Toshio Nakao 1 person
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an electrical diagram of an embodiment of the
present invention, FIG. 2 is an electrical diagram of another embodiment of the present invention,
and FIG. 3 is a displacement characteristic diagram of the vibrating membrane with respect to
frequency. . The present invention relates to a device for measuring the tension of a vibrating
film, such as a detailed description of the present invention, and in particular, it is an object of
the present invention to provide a device that enables highly efficient and highly accurate tension
measurement. Hereinafter, embodiments of the present invention will be described with
reference to the drawings. First, in FIG. 1, 1 is a condenser type microphone or speaker having a
conductive vibrating film 2 whose load is to be measured and a load electrode 3, 4 is a drive
amplifier for driving the diaphragm 2 of the microphone or speaker 1, and 5 is the above. The
electrode for displacement detection fixedly installed facing the diaphragm 2 at a predetermined
interval in front, the input terminal is connected to the displacement detection electrode 5, and
the output terminal is the input terminal of the drive amplifier 4 and the counter 7 is a detection
amplifier connected to 7 respectively. A series circuit of a resistor 8 and a polarization voltage
source 9 and a series circuit of a resistor 10 and a polarization voltage source 11 are connected
between the charge electrode 3 and the ground or between the displacement detection electrode
5 and the ground, respectively. There is. Also, the vibrating membrane 2 is grounded. The
operation of this device will now be described. First, when the vibrating membrane 2 is driven by
applying the output from the drive amplifier 4 and the voltage from the polarized voltage source
9 through the [111111] resistor 8 to the vibrating membrane 2, the polarized voltage source 11
passes through the resistor 10. A displacement signal corresponding to the vibration of the
vibrating membrane 2 is obtained between the vibrating membrane 2 to which the polarization
voltage is applied and the ground. The displacement signal is amplified by the detection amplifier
6 and applied to the drive amplifier 4 to form a feedback loop. It is well known that this feedback
loop oscillates if the feedback gain is 1 or more and there is no phase difference. FIG. 3 shows
frequency characteristics of displacement of the diaphragm 2 and phase characteristics thereof.
As apparent from FIG. 3, the resonance frequency f. The odor is the largest displacement, and
there is no phase difference. Therefore, if other elements in the loop have flat characteristics,
oscillation occurs at this frequency. Therefore, if the oscillation frequency is measured by the
counter 7, the resonance frequency f. Is obtained and determined from this. In the embodiment
of FIG. 1, although the displacement of the diaphragm is detected using the displacement
detection electrode, it may be detected using a high frequency. An embodiment in this case is
shown in FIG. In FIG. 2, 12 is a high frequency choke coil, 13 is a DC blocking capacitor, 14 is a
high frequency oscillator, 15 is a tank circuit, and 16 is a rectifying and smoothing circuit.
Since the measuring operation of this device is basically the same as that described in FIG. 1, the
description here is omitted. As described above, according to the present invention, the tension of
the vibrating membrane can be measured efficiently and accurately with a very simple
Без категории
Размер файла
9 Кб
Пожаловаться на содержимое документа