JPS6093314A - Acoustic volume measuring device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for defining the volume inside a closed container such as a fuel tank for an automobile, and particularly an acoustic volume measurement device that measures the volume of a closed container such as a fuel tank for an automobile. Regarding equipment.

<Prior Art> As shown in Figure 1, a conventional fuel gauge for a fuel tank for an automobile has a fuel gauge that is connected to the tank tip. 7'I & III fixed volume container 1
Inside, one end of an arm 12 is movably attached to the upper part (b), and a float 13 is attached to the lower end of the arm 12. The float 13 is suspended on a liquid 14, such as fuel, inside the container 11. Therefore, when the liquid level of the liquid 14 rises and falls, the float 13 also rises and falls, and the arm 12 rotates accordingly, and the rotation of the arm 12 causes the adjustment shaft of the wire-wound resistor 15 to rotate. The volume of the liquid 14 was measured by calibrating the resistance value of the wire-wound resistor 15 and the volume of the liquid 14 or the volume inside the container 11 (volume between nitrogen gases) in advance.

In this case, when the liquid level of the liquid 14 fluctuates, the average '/&+1u level of the float 13 also becomes lower or lower, making it impossible to measure correctly. Similarly, if the container 11 is tilted, accurate measurements cannot be made. In this way, the level of the 70-t 13 is detected by the co-movement angle of the rotary arm 2, and the wire-wound resistor 15 is further rotated by the co-move arm 12. In other words, it is not detected mechanically. be. When such a device is attached to something that is subject to a lot of vibration, such as a vehicle, it is mechanically weak, has poor durability, and has a short lifespan. Furthermore, the amount of liquid 14 in the tank 11 was so small that it was impossible to perform measurements in an almost empty state.

It has been proposed that the volume inside the vessel to be measured be measured from the J^' wave number when it resonates using Helmholtz resonance, by giving the name of Shinsho 1 in the vessel to be measured. There is.

The Helmholtz resonance is determined only by the inner 8 nuclei of the container, and therefore the adjustment is difficult and the measurement frequency cannot be freely selected.

<Purpose of the invention> The purpose of the present invention is to be able to adjust the measurement frequency by selecting not only the internal volume but also the redundancy of the transducer, which has a high degree of freedom, and is also suitable for measuring liquid volume. The object of the present invention is to provide an Otochi type mustard side shock absorber that is not affected by liquid level fluctuations. Another object of the present invention is to provide an acoustic volume defining device capable of subrectangularization with a relative 1M31/-1 sensitivity. Still another object of the present invention is to provide a sound format valley record side device which carries a correction circuit for correcting the measured detected value and the volume so that they have a linear relationship. Another object of the invention is to provide an acoustic volumetric device which allows the transducer section to be handled with a relatively small cover.

<Summary of the Invention> According to the present invention, an electroacoustic transducer is provided in the sealed container to be measured, and the volume inside the sealed container can be changed by the electroacoustic transducer. The electroacoustic transducer is driven by applying electrical signals of a plurality of consecutive frequencies. At this time, the resonance Ayasaka number, which is determined by the volume inside the sealed container, that is, the volume of the space, and the constant of the electroacoustic transducer, is detected as an electrical signal, and the volume inside the sealed container can be estimated from the detected frequency. Ru. The electro-acoustic transducer is driven by electric signals of a plurality of continuous frequencies, for example, by generating a sweep signal, controlling the fixed frequency of the variable frequency oscillator by the sweep signal, and using the oscillation output to generate electricity. This is done by driving an acoustic transducer. Alternatively, a pulse may be applied to the electroacoustic transducer and the electroacoustic transducer may be simultaneously driven by multiple frequency components contained in the pulse.

Further, according to the present invention, a vertically extending tube is provided in the closed container below the electric lamp, and the lower end of the tube communicates with the inside of the container. A resonant frequency determined by the volume and the number of stains of the electroacoustic transducer is detected, and the volume inside the smart canal is measured from that frequency. In this case, a liquid is generally placed in a sealed container to be measured, and as the level of the liquid changes, the volume inside the sealed container is liquefied. Detect the resonance frequency as shown in d11
1 can be determined.

By providing the tube in this way, the city sensitivity of 01
This is an example of 0 constant. The length and shape of the tube are selected so that the relationship between the volume inside the closed container due to a change in the group level in the container and the number of protruding slopes is like the iM line.

In addition, in order to establish a linear relationship between the detection frequency and the measurement volume, it is necessary to make the sweep characteristics of the sweep signal non-linear as described above.
This can also be done by providing a u positive circuit. The resonant frequency is detected as a level signal having a level proportional to the time from the start of the first cut until a peak is obtained on the input side of the electric sound V converter, and the level signal is converted to a non-linear signal using a correction circuit. It is also possible to correct the relationship between the detection plate wave number and the measurement volume to be direct. In history, a cover is provided on the back of the electroacoustic transducer to cover it, and the volume inside the cover is set to be equal to or larger than the maximum inner volume of the tube.

<First Embodiment> Hereinafter, an embodiment of the acoustic volume defining device according to the present invention will be described with reference to the drawings. In FIG. 2, the sealed container 11 to be measured has an opening 16 formed in its upper plate in this example, and an electroacoustic transducer 17 is attached to the sealed container 11 so as to close the opening 16. What about the electric cross switch 17? +I
For example, it is possible to use a speaker of a flow wire type, and its cone peripheral portion is connected to the inner peripheral wire portion of the opening 16 to close the opening 16. Therefore, by driving this electroacoustic transducer 17 with an alternating current signal, the internal volume within the closed container 11 can be changed. In this example b
・The liquid 14 is placed inside the closed container 11. Therefore, the volume of the liquid 14 can be calculated by adding 6411 to the volume inside the foldable container 11, that is, the volume of the space other than where the liquid 14 is taken out. Is it possible to measure it?

The electroacoustic transducer 17 is driven by supplying an electric signal with a continuous frequency. A sweep signal generator 18 is provided, from which a sweep signal 19 whose voltage varies with time in a sawtooth manner as shown in FIG. 3A is generated. This sweep signal 19 controls the VCO 21, which is the source of pressure control, and the VCO 21 repeats the cycle 7) as shown in FIG. 3B over time. Oscillation output can be obtained. This oscillation output is supplied to the electroacoustic transducer 17 through the amplifier 22,
Electroacoustic transducer 17 is activated. Therefore, the volume inside the closed container 1 is changed.

All resonant frequencies determined by the volume V in the closed cloth container 11 and the constant of the '-air sound transformation 17 are detected. For this reason, a full temporary current accumulator 23 is connected to the input side of the electric rewriting converter 17, and a peak of the rectified output of the full rectifier 23 is detected by a peak detection circuit 24.

'When the driving frequency for the electroacoustic transducer 17 matches the resonance frequency fm determined by the constant of the electroacoustic transducer 17 and the volume of the container 11, the signal amplitude on the input side of the electroacoustic transducer 17 becomes significantly large. Become. Therefore, as shown in FIG. 3C, a peak 25 occurs in the signal level on the input side of the electric sound V converter 17 when the drive signal frequency f reaches the resonance frequency fm. As shown in FIG. 3A, the sweep signal 19 changes in the range of voltages E1 to E2 in a sawtooth wave manner, and accordingly, the oscillation (drive) frequency f changes in the range f1 to f2 in a sawtooth wave manner. However, the frequency f is the resonant frequency fm
When this happens, the amplitude of the signal at the input side of the electroacoustic transducer 17 becomes significantly large, and a peak 25 appears. Therefore, in the output of the peak detector 24, a pulse 26 is generated at a portion corresponding to the peak 25, as shown in the third diagram. The level Em of the sweep signal 19 when this pulse 26 is obtained is sampled and held in the sampling and holding 10J path 27 as shown in FIG. 3E. This level 12m is the resonant frequency ifm of the older oscillator 21
The sampled holding voltage 12m is converted into a digital signal by the AIJ hair comb 28 and displayed on the display 29.

In this case, the resonance frequency lc9. As mentioned above, fm is determined by the internal volume (2) of the container 11 and the capacity of the converter 17, and since the constant of the converter 17 is constant, it corresponds to the volume (2). Therefore, the detected frequency fm corresponds to '[1 pressure E
By adjusting In and the cap V in advance, the internal volume V of the container 11 can be displayed on the display 29.

Time from start of sweep until peak pulse 26 is obtained △
t to detect the resonant frequency f+n, and then 'i
It is also possible to measure the internal volume V of the g vessel 11. 1 An example is 6LS 1 Sweep signal generator 1 as shown by dots in the figure
8, the counter 31 starts counting the clock from the clock generator 32, and by stopping the iXl number by the pulse 26 from the heat output device 24, it is possible to measure △t. The relationship between the resonant frequency fm and the internal volume V is shown in Fig. 4.
There is a relationship shown in , and the volume of the liquid 14 increases and the internal volume V
When V becomes smaller, the resonant frequency becomes higher, and when the liquid 14 decreases and the internal volume V becomes larger, the resonant frequency becomes lower. By displaying the details V corresponding to the detected resonance j wave number fm on the display 29 by utilizing the relationship of this song IfM33, it becomes possible to directly read the internal volume v of the container 11.

It should be noted that the impedance of the electroacoustic transducer 17 when viewed from the input side of the transducer 17 when the resonance occurs is changed by changing the frequency of the signal that drives the electroacoustic transducer 17. As shown in FIG. 5, an impedance peak 34 is obtained at the resonant frequency fm determined by the volume V and the constant of the electric octopus 17. When the drive signal frequency is further increased, peaks 35, 36, and 37 are sequentially obtained. This peak 35 is obtained at frequency F1 due to resonance when the distance H from the electroacoustic transducer 17 to the liquid surface of the liquid 14 becomes one wavelength of the drive signal.

Beak 36 is at that frequency, E5. Frequency F2 twice that of Fl
The resonance that occurs when the two wavelengths of the drive signal become equal to () can also be avoided.

Furthermore, the frequency F''n at which the peak 37 is observed is obtained when resonance occurs in the transverse direction of the container 11.

As shown by curves 38 and 39 in Fig. 4, these peaks 35 and 36 are obtained at higher frequencies as the distance from the height of the liquid 14 to the transducer 17 becomes smaller. , H increases, a peak occurs at a lower frequency. However, since the peak 37 is resonance in the lateral direction of the container 11, it occurs at a constant frequency regardless of V and H, resulting in a characteristic as shown by a straight line 41.

Figure 2 shows Tanibe's 7Je [l:! A concrete example of the l-way is shown in FIG. ν1", that is, the sweep signal generator 18, the amplifier 42, the resistor 43, and the capacitor 4.
4 generates a voltage that gradually changes as expressed by
The output of the operational amplifier 42 is compared with the 0 level by the comparator 45, and when it exceeds the 0 level, the diode 46 is passed through the resistor 47, the capacitor 44, and the operational amplifier 42, and integration is rapidly performed in the reverse direction. The integral output of the amplifier 42 is 0
When it becomes below the level, capacitor 44 and resistor 43 are connected again.
Integration is performed by Zener diode 48 is an amplitude limiter.

The output of the sweep signal light source 18 is applied to an inversion level converter 49, and its output is applied to the control@1j terminal of the VCO 21. The VCO 21 oscillates at a frequency corresponding to the voltage applied to the control terminal of the VCO 21 . Inside the VCO 21, an Oj step-up amplifier 51, a resistor 52, a capacitor 53
The output of the integral triangular wave signal generator is outputted to O by the comparator 55.
The multiplier circuit 56 obtains the product of the + and - outputs of the ratio softener 55 and the output voltage of the inverting level converter 49. The output of this multiplication circuit 56 is integrated through a resistor 52 and a capacitor 53 between squares or in the opposite direction. The output of the operational amplifier 51 is converted into a sine wave No. 100 by the Toba circuit 57, which then passes through the output amplification circuit 22, from which the output impedance adjustment resistor 58 is connected to the "Kameki acoustic transformer 17" via Q. It will be offered.

The full-wave rectifier circuit 24 connected to the input side of the electric tone converter 17 is a full-wave rectifier circuit including an operational amplifier 59.
The Jinkagogo is rectified and further smoothed [1st path 61 is flat-toothed. The output of the smoothing circuit 61 is that in the peak detection circuit 24, the differentiated by the differentiator 62 and the undifferentiated are passed through circuits 63 and 64, respectively, and are ANDed by a Nant gate 65. A peak output pulse is received as the output of the Nandt gate 65, and the output of the inverting level converter 49 is maintained at its original level in the sampling/holding circuit 27 due to this pulse.

<Example 2 of 2 meters> In the seventh case, a tube 66 is provided to extend between the upper and lower sides in the sealed in-vehicle 11.

Above the tube 66, an electric sound/sound changer 17 is placed. The lower end of the tube 66 advances through the communication hole 67 and connects with the inside of the closed canyon. Therefore liquid 14
The liquid level [fI] in the tube 66 is also the same. The volume inside the tube fluoro, ie, the volume V of the upper part of the number body 14, and the volume V inside the container 11 correspond to each other on a one-to-one basis. Therefore, in the same way as shown in Figure 2, you can hear the electric sound! #7 - VfAV of the container 11 can be measured by applying a drive signal to the transducer 17 and detecting the resonance frequency determined by the constant of the electroacoustic transducer 17 and the volume v inside the tube 66.

In this case, the tube 66 is small in the lateral direction, so the lateral resonance frequency is high, and the frequency at which peak 37 is obtained in FIG. Even at peak 37, malfunctions can be prevented. Furthermore, if the resonant frequency is detected when the volume v inside the container 11 is small, as can be seen from the song 33 in FIG. is large, therefore, it is possible to perform highly sensitive and accurate determination of h+.

<8143 Embodiment> As shown in FIG. 148, a cover 68 is provided on the back of the electric sound 111 transducer 17 to hide it from the outside, which can be easily done by using a tube 66. The self-resistance R of the cover 68 is set to be equal to or greater than the maximum value of the content 4Jtv of the tube 6G. That is, in order to eliminate the influence of the back pressure of the air exchanger/shaft exchanger 17, the back of the electric layer #momata device 17 and the outer γ5 side of the storage container 11 may be opened to the atmosphere. There are cases where it is required to prevent water from getting into the electrical equipment 17 and from getting nicked, and furthermore, when it is required to have an explosion-proof 4'N construction. In these cases, it is necessary to put a cover on the 3rd vessel 17, but the second
L! When the tube 66 is not used as in the case shown in 1, a container (-) is used which has an internal volume equal to or larger than the maximum internal volume V of the sealed container □ container 11 when the liquid 14 is 0. If not, the back pressure of the electric sound* transducer 17 may affect the measurement.In other words, a cover with a volume equal to or larger than the space to be measured is required.

In the case of ρ shown in FIG. 8, 11 parts of the tube 66 become a constant space 6111, so it is possible to use a small cover 678? It is possible to perform accurate measurements without being affected by the back pressure of the L-consonant transducer 17, and furthermore, it can be shielded by this cover 68 from the outside group. It also has an explosion-proof structure.

If the tube 66 is not provided, the maximum content is 1 more than V.
]I If a small cover 68 is provided, the song I in Fig. 9
S! As shown by 69, the volume of the liquid 14 in the container 11 ■1
In the case where there is a small number of
is determined by the volume of the container 11, and is constant, and when the volume d in the container 11 is the same or smaller than the volume of the cover 68, that is, when the liquid volume V' in the container 11 is large and close to full, the container 11 is Due to the influence of the internal volume (■), the resonant frequency suddenly increases, making it virtually impossible to determine the correct sub-electrode. However, by providing the tube 66, the container 1
A characteristic of a curve 71 in which the resonant frequency gradually changes with respect to the liquid volume V' in 1 is obtained, making it possible to set 61 correctly.

Fourth Embodiment> As shown by the curve 33 in FIG. 4, the volume V inside the container 11 and the resonance frequency generally have a non-linear relationship. Therefore, if we make this into a linear relationship, it is true. The shape of the tube 66 can be selected for this purpose. That is,
Similarly to the curve 33 in FIG. 4, the relationship between the resonance frequency f and the volume V inside the tube 66 when the tube 66 is used is as shown in FIG. 10A. When the resonance frequency e is small, the volume V is When f is large, the volume V becomes small, and this changes in a non-if 8M manner. The relationship between the wavelength T, which is the reciprocal of the frequency f, and the volume V is the first
As shown in FIG. As shown in Figure C, when the 101st prisoner C is A hM = h (becomes Tl, follow -)
= AT, and the volume ■ is linearly proportional to the wavelength T, as shown in the 10th diagram. That is, the 10th
The shape of the tube 66 may be selected so that the relationship between the first case C and the 101st case C is obtained. For example, when the container 11 is a rectangular parallelepiped as shown in FIG. 11, the tube 66 is shaped so that its horizontal cross-section becomes wider toward the bottom or one side of the tube, thereby increasing the measurement frequency f and the measurement volume. A linear relationship with V can be obtained.

<Fifth Embodiment> In this way, the relationship between the detection frequency f and the volume V of the container 11 can be made linear by electrically. For example, when the relationship between the volume of the container 11 and the resonance frequency t4 is a curve of f=g(Vl) as shown in FIG. 12A, as shown in FIG. 12B, the sweep in FIG. From the start until the resonant frequency if is 4+00,'J11Jt and the resonant frequency f, the relationship between the functions of f=Ag(tl) is made to be one thread.In this way, g(v)2A・g (t)
Therefore, V=A-t, and as shown in FIG. 12C, the relationship between tl, that is, the time t at which the resonance frequency f is obtained from the start of the sweep, and the volume 2 becomes linear. As mentioned earlier, this time t may be the counted value of the counter 31 in FIG. 2, or the sampling holding circuit 27 in FIG.
The sample value Em may also be used.

In order to obtain such a relationship between L and f, for example, the first
As shown in FIG. 3 with the same reference numerals assigned to parts corresponding to those in FIG.

By using the correction circuit 72, a non-linear sawtooth wave signal is converted into a sweep signal, as shown, for example, by the dots in FIG. 3A.

Such a non-linear sawtooth signal can be obtained by polygonal line approximation. For example, in correction 11 path 72, human power is V
If R4 or less, the output of amplifier 101 path 73 is added lI]
When the input exceeds VH2, the output of the amplifier circuit 73 is amplified.
1'J path 74, and when the input exceeds VB2, the output of the amplifier circuit 76 is added to the history, and when the input exceeds VH6, the output of the amplifier circuit 77 is further added, and as a result, the first
As shown in FIG. 4, 78 characteristic surfaces il whose appearance increases non-linearly with respect to human power are obtained.

<Sixth Embodiment> In order to obtain the relationship shown in the twelfth example, for example, the output of the latch circuit 27 may be non-linearly converted by a correction circuit 78 as shown in FIG. The voltage input/output relationship of this correction circuit 78 can be made to have a desired nonlinearity by, for example, a configuration similar to that of the correction (b) path 72 in FIG. 13.

Note that FIG. 13 specifically omits the counting operation by the counter 31 in FIG. 2. In other words, at the start of the sweep, VC
The signal from the control terminal of O21 is applied to the flip-flop 82 through the circuit 81, and this is set.The counter 31 is enabled to operate by its Q output, and the monostable multipipe rake 83 is driven by this rising edge. Ru.

Counter 3 is activated by the output of monostable multivibrator 83.
The count value of 1 is latched in the latch circuit 84, and the multivibrator 85 is driven, the output of which clears the counter 31, and the counter 31 starts counting the clocks of the clock generator 32. When a peak is detected by the peak detection circuit 24 in this clock counting state, the flip-flop 82 is cleared, and therefore the counter 31 becomes unable to count, and the count value up to that point, that is, the value corresponding to Δt in FIG. 3, is cleared. is counted and held in the counter 31.

<Seventh Example> As described with reference to FIG. 5, when the frequency is swept from the lower side, the peaks are 34 and 35.

36 and h are sequentially detected. Therefore, the first peak 3 obtained
By determining that the resonance is based on the volume V based on 4, a correct 8111 constant can be performed. However, in some cases, as shown in Figure 15, the peak 3 due to the primary resonance of H
4 is obtained first, and then a peak 35 based on the volume V is obtained, so it is not necessarily the case that the resonance based on the volume V is obtained first. That is, as shown in FIG. 16, there are cases in which a first-order resonance one-uniformity curve 38 for the quotient H is parallel to the relationship characteristic curve 33 between the volume V and the resonant frequency, and this intersection point In the case where the volume V is relatively small, the primary resonance of the axle H occurs first, resulting in the state shown in FIG. 15.

In such a case, the present invention detects the resonance determined by the volume V or V and the constant of the electric sound V converter 17, that is, the volume V or V of the side rectangular space.
The resonant frequency f=YE is determined by the spring constant of the converter 17, that is, the number of runs determined by the stiffness, and the quality Mm of the movable part of the converter 17. The electro-acoustic 2π transducer 17 is, for example, a water-immersed magnet 86 as shown in FIG.
A moving coil 8 is placed within the ring-shaped magnetic gap formed by
7 are arranged coaxially, a cone-shaped diaphragm 88 is connected to the 'EiJ moving coil 87, this diaphragm 88 closes the opening 16 in FIG. When it vibrates back and forth in the direction, the distance is III! 88 vibrates, and the volume within the container 11 or the volume within the tube 66 is vibrated.

For example, by attaching a correction height 89 to this moving coil 87,
By setting nl in the equation for the resonant frequency to dog, the number of resonant frequencies is lowered, and as a result, the number of resonant frequencies becomes as shown in curve 331 in FIG. It can be positioned to the left of the curve 38 in the figure so as not to intersect the curve 33'%l/curve 38.

In this way, the shift can be detected without error as resonance since the first peak obtained is also in the volume of 6ilj constant space m1. In addition, if the tube 66 is not provided, the lateral resonance characteristic curve 41 will be relatively low as described above, and the resonance peak 37 may appear at a relatively low frequency, which may prevent malfunctions due to the resonance peak. For example, by using the tube 66,
It is also possible to obtain a transverse resonance peak 37 at a high frequency as indicated by 1'.

<Eighth Embodiment> In the above description, continuous frequency signals are sequentially supplied to the electric/acoustic converter 17 by sweeping, but such continuous frequency signals may be supplied simultaneously. For example, as shown in FIG. 18, from the pulse generator 91, as shown in FIG.
A pulse with steep rises and falls as shown in FIG. In this way, many frequency components are generated at the time of the rise or sudden change in the vertical position, and the resonant frequency determined by the volume V in the container 11 (V is V) and the constant of the converter 17 is uniform. Only the matching frequency components appear as large damped vibrations as shown in FIG. 19M.

This is the waveform shaping circuit 9 connected to the input side of the converter 17.
3, the vibration is amplified by the amplifier 94 in FIG.
It is converted into a diagonal square wave (Fig. 19M) with 0 level. This square wave is the clock terminal ck of the soft register 96.
A high level is applied to the data terminal of the shift register 96, and a pulse generator 9 is applied to the clear terminal ct.
A pulse of 1 is applied, and the clear state is maintained during the high level of the pulse. When the pulse in FIG. 19A falls and the first square wave from the comparator 95 causes the shift register 96 to
The first output is still at a low level as shown in FIG. 19M, and the second output Q2 is at a high level as shown in FIG. 19M. This Q2 output is inverted by an inverter 97 as shown in FIG. 19G, and this and the Q1 output are supplied to an AND gate 98. Therefore, as shown in FIG. 19M from the AND gate 98, the level is still output from the first period of the square wave (FIG. 19M). This output is made into a pulse of a predetermined level (Fig. 19 ■) by the reference level pulse generation circuit 99 according to the bamboo type, and if further non-linear correction is performed, the pulse width is corrected through the OL circuit 01. , the pulse shown in FIG. 19J is obtained.

1Ii between this pulse and the input and output of the inverter 97
The Il fill is taken by AND gates 102 and 103, respectively, and counter 104 is reset by the pulse shown in FIG. 19M from AND gate 102. Depending on the output of the AND gate 102 (M in FIG. 19), whether the gate 105 is [
From i:J, the clock of the clock generator 106 in the pulse generator 91 passes through this gate 105, and the clock is counted by the number h1 in the counter 104. I hate this count.
i It corresponds to one cycle of the Kayo Bogo in Figure 19C, and corresponds to the volume V of the container 11 or the volume V of the tube 1)6, and this corresponds to the volume V of the container 11 in the container 107. It is designated as V. , the clock of the clock generator 106 is divided by 11. in the pulse generator 91. 'Jlkj108 divides the frequency to obtain the pulse shown in FIG. 19A. When the output of the AND gate 102 falls, the monostable multivibrator 10
9 is driven, the count value of the clock 104 is latched by its output into an internal latch circuit, and the latch output is supplied to the display 107.

As mentioned above, the period T of the vibration signal and the volume V or V in FIG. Reference level pulse generation [1st path 99 sets the level of 1 period pulse of Fig. 19 M to a constant level (% pressure) as shown in Fig. 19 1
This is a one-period pulse.

This negative level pulse is applied to the integrating circuit 1 in the correction circuit 101.
11, the signal is integrated as shown in FIG. 19M.

This integration is performed during the period when the switch 112 is turned off by the one-period pulse shown in FIG. 19M. The output of the integrating circuit 111 is offset by an offset circuit 113 as shown in FIG.
is input to. The first corner amplifiers 115 to 118 have bias values V kl 4 , VR5, VR6, and V similar to those described for the correction circuit 72 in FIG. 13, respectively.
R7 is given. The output of the offset circuit 113 and each output of the amplifiers 115 to 118 are added by an adder circuit 119. As shown in FIG.
The outputs b - e of 8 are respectively input, and their sum values are as shown by the curve f in Figure 19 O, and the output of the adder circuit 119 is non-+f = non-+f =
It will be related to KG.

The output of the adder circuit 119 is charged 7t to the capacitor 122 through the diode 121, and this charging voltage corresponds to the OFF period of the switch 112, that is, the intercostal interval of the 1j^'' period pulse in FIG. 19H. The switch 112 turns on and the output of the adder circuit 119 becomes zero, but the diode 12
1, the capacitor 1220 charge pressure is maintained. When the output pulse (K in FIG. 19) of the AND gate 1o3 falls, the switch 123 is turned on, and the constant current circuit 124 operates to discharge the charge in the capacitor 122 with a sudden current. Therefore, the output of the buffer circuit 125 indicating the voltage of the capacitor 122 is the vibration signal (
The voltage decreases at a constant speed from the voltage value corresponding to one cycle in FIG. 19C). The output of this buffer circuit 125 is the comparator 12
6 is compared with the 0 level, and its output becomes as shown in FIG. The pulse width in Figure 19 corresponds non-linearly to one cycle of the vibration signal in Figure 19C. 1st
9R shows the clock passed through the gate 105, and FIG. 19S shows the output latch command of the monostable multi-bi break 109.

<Effects> As described above, according to the sound response volume measuring device according to the present invention, the volume V of the container or, if a liquid is contained in the container, the volume of the liquid can be measured using a phonetic signal. In this case, there are no mechanical parts as described in Fig. 1, so it is resistant to vibrations 4 and operates stably.
It has a long life and can accurately measure the volume + MV even if the liquid level partially fluctuates.31 Since there are no mechanical restrictions, if the liquid level is 14 or less, that is, it is close to empty. volume can be measured correctly even if the

By not using the tube 66, the entire measurement sensitivity can be increased, and the measurement can be made more accurately.
Correct measurements can be made without being influenced by lateral resonance. Transducer 1 when using tube 66
7 can be removed with a relatively small cover,
Moreover, accurate measurements can be made. Father, in this invention, the resonant frequency is not determined by the volume V or V in the container, but by the volume V or ■ of the transducer 1.
Since the resonant frequency P: is detected by both the constant of P and the constant of 7, it is necessary to adjust the constant of the transducer 17 when there is a relationship as shown in FIG. 15, as described in FIG. 17 above. Therefore, the correct measurement can be easily obtained, or even if there is no such relationship, the measurement tube wave number can be selected by adjusting the transducer's housing, which allows a greater degree of freedom in the design. becomes easy.

Further, by selecting the shape of the tube 66, the relationship between the detection frequency and the measurement volume can be made linear, and accurate measurement with uniform error can be performed. In order to obtain such linearity, Figs. 2 and 13
It is also possible to correct the error using a circuit as described with reference to FIGS.

In the above description, the volume was measured when there was a liquid in the container, but the present invention can also be applied to volume measurement when there is no liquid. can be selected arbitrarily.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a conventional volume measuring device, FIG. 2 is a block diagram showing an example of a sound material type volume measuring device according to the present invention, and FIG. 3 explains the operation of FIG. 2. Figure 4 is a characteristic diagram showing the relationship between volume and resonance frequency, Figure 5 is a characteristic diagram showing the relationship between frequency and converter impedance, and Figure 6 is Figure 2. 7 is a sectional view of the container portion showing an example of the acoustic volume measuring device according to the present invention using a tube 66, and FIG. 8 is a connection diagram showing the specific configuration of the circuit in the valley of Fig. 9 is a cross-sectional view of the container part showing the state in which the tube is attached, Fig. 9 is a characteristic diagram showing the relationship between liquid volume and resonant frequency with and without a tube when a cover is used, and Fig. 10 is a characteristic diagram showing the relationship between the liquid volume and resonance frequency. A characteristic diagram showing each relationship for making the relationship between the container volume, the tube volume, and the resonance frequency linear. FIG. 11 shows an example in which the relationship between the resonance frequency and the container volume is made linear by the tube 66. Container break…” Figure, Figure 12F
A characteristic diagram showing the relationship between i detection time, resonance frequency, and volume,
FIG. 13 is a connection diagram showing a specific example of the source side using a correction circuit, FIG. 14 is a diagram showing an example of the characteristics of the correction LOJ path 72, and FIG.
Figure 5 is a characteristic diagram of several innovidances at the frequency θ where the primary resonance first appears, Figure 16 is a diagram showing the volume-resonance frequency corresponding to Figure 15, and a diagram showing the relationship between co-stationary frequency r, and Figure 17 is a diagram of the transducer. FIG. 18 is a cross-sectional view of the auxiliary device part showing an example in which a mass is added to the converter 17. FIG. It is a waveform diagram of Nodame. 11: Sealed container to be measured, 14: Liquid, 17: Electrical converter, 18: Sweep signal generator, 21: External frequency converter, 22: Output amplifier, 23: Full-wave rectifier circuit, 24 : Peak familiarization circuit, 27: Latch circuit, 28: l) A converter, 29, 107: Display, 31, 104: Counter, 3
3: Clock generator, 66: Tube, 67 dual communication port,
682 cover, 72, 1 '01: Correction (b) road,
89: Additional mass. Patent Applicant Yazaki Agyo Co., Ltd. Agent Takashi Himo '7I72 Figure O 3 Figure 7177 Figure V O 8 Higunku Cavity Volume Well 10 Figure 714 Figure 1 # 15 Figure fz f flf 716 Figure 717 Procedural Amendment ( (Voluntary) Commissioner of the Japan Patent Office Display of 10 Patent Applications 1984-2014422 Title of the Invention Relationship with the masterpiece that corrects the stone sound volume measuring device 3 Patent applicant Yazaki Sogyo Co., Ltd. 4, Agent Tsuku 33 4-2-21 Shinjuku, Shinjuku-ku, Tokyo
Therefore, in the output of the full-wave rectifier 23, a pulse 26 is generated at a portion corresponding to the peak 25 as shown in the third diagram.This pulse 26 is detected by the peak detector 24. At the time of detection, the sweep signal 19 is corrected. (2) Ibid. 22, Tei lines 18-20 “It may be a count value, but...
...The sample value Em may be used. ” ヲ ``A count value is fine.'' Correct it. (3) The same book, page 29, line 9 “And Gate 1o2”
Top 72 Figure 7I-3

Claims (8)

[Claims] (1) A sound converter that is installed in a sealed container to be measured and can change the volume inside the container, and a sound converter that is installed in the sealed container to be measured and its sound converter are electrically connected to a continuous mantissa frequency. A driving means driven by a signal, and a detection means electrically detecting a resonant frequency determined by the volume inside the sealed container to be measured and the number of pheasants of the electroacoustic transformer, and one of the detection means is developed. Chang format: Taniko measuring device that calculates the volume inside the airtight container from the round number. (2) An electric #acoustic transducer in which liquid is contained in the measuring sealed device, and the internal volume can be changed by being provided in the sealed container, and the above-mentioned It is installed in a sealed container, and the upper part of the body is placed in a closed container.
A tube communicating with the inside of the sealed container in the capital,
A driving means for driving the electroacoustic transducer with electrical signals of a plurality of frequencies that are delayed in sequence, and a detection method for electrically detecting a resonant frequency determined by the volume inside the tube and a constant of the electroacoustic transducer. and means for measuring the volume inside the sealed container from the detected wave number. (3) Select the relationship between the volume of the sealed container as the level of the liquid in the sealed container changes and the volume of the tube, so that the configuration frequency and the volume of the sealed container have a linear relationship. 3. The reverberant tail measuring device according to claim 2, wherein the shape of the tube is selected so that: (4) A liquid is stored in a sealed container to be measured, and an electro-acoustic V transducer capable of changing the volume inside the sealed container, and a vertical direction inside the sealed container below the electro-acoustic transducer. a tube provided as a chamber and whose lower part communicates with the inside of the sealed container; a detection means for detecting a resonant frequency determined by the volume inside the tube and a constant of the electroacoustic transducer; It is provided to cover the back,
An acoustic volume measuring device, comprising: a cover having an internal volume equal to or larger than the maximum volume within the tube, and measuring the volume within the sealed container from the detection frequency. (5) An electroacoustic transducer that is installed in the sealed container to be measured and can change its internal volume, a sweep signal generator that generates a sweep signal, and the frequency is changed by the sweep signal to generate an oscillation output. a variable frequency oscillator that supplies a driving signal to the electroacoustic transducer; a peak detection means that detects the peak of No. 18 amplitude on the input side of the electroacoustic transducer; An acoustic volume measuring device comprising: a correction circuit that makes the sweep characteristics of the sweep force non-linear so that the chest wave number of the container and the volume inside the closed container have a 11-correlation relationship. (6) An electroacoustic transducer that is installed in the sealed container to be measured and can change the volume inside the sealed container, a sweep signal generator that generates a sweep signal of 1 g, and a sweep signal generator that generates a sweep signal of 1 g. a variable frequency oscillator whose number is varied and supplies an oscillation output to the electroacoustic transducer as a drive signal; a peak detection means for detecting the peak of the signal amplitude on the input side of the electroacoustic transducer; a switching means for obtaining a level signal having a level proportional to the time from the start of the sweep to the detection of the peak; An acoustic volume measuring device, comprising: a correction circuit that corrects the volume automatically. (7) An electroacoustic transducer that is installed in the sealed container to be measured and can change the volume inside the sealed container, and a pulse that is connected to the electroacoustic transducer and applies a steep rising or falling pulse. A resonance that is connected to the input end of a generator and its electroacoustic transducer, occurs immediately after the steep rise or fall, and is determined by the volume inside the sealed container to be measured and the constant of the electroacoustic transducer. An acoustic volume measuring device comprising: a circuit for extracting a damped vibration signal having a frequency; a circuit for shaping the waveform of the damped vibration signal; and a period measuring device for measuring the period of the waveform-shaped output. (8) Electrical sound converter that can be provided in a closed container and can change the volume in the sealed container, and the turtle sound conversion instrument, and the electricality of the number of remaining numbers of the remaining number of sodium. a detection means for electrically detecting a resonant frequency determined by the volume of the fixed casing closure V1 and the footing of the electroacoustic transducer; and an additional mass attached to a movable part, the acoustic volume measuring device measures the volume inside the sealed container from the detection frequency.