JPH045355B2 - - Google Patents
Info
- Publication number
- JPH045355B2 JPH045355B2 JP20922285A JP20922285A JPH045355B2 JP H045355 B2 JPH045355 B2 JP H045355B2 JP 20922285 A JP20922285 A JP 20922285A JP 20922285 A JP20922285 A JP 20922285A JP H045355 B2 JPH045355 B2 JP H045355B2
- Authority
- JP
- Japan
- Prior art keywords
- ultrasonic
- counting
- oscillating
- output
- distance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 27
- 238000005406 washing Methods 0.000 claims description 15
- 230000003321 amplification Effects 0.000 claims description 6
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 6
- 230000000630 rising effect Effects 0.000 claims description 3
- 230000010355 oscillation Effects 0.000 description 12
- 238000010586 diagram Methods 0.000 description 8
- 238000005259 measurement Methods 0.000 description 6
- 230000002238 attenuated effect Effects 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、超音波の被測定物までの伝播時間に
より距離を算出する洗濯機の超音波式距離装置に
関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an ultrasonic distance device for a washing machine that calculates distance based on the propagation time of ultrasonic waves to an object to be measured.
従来の技術
従来のこの種装置は、第４図のように、１つの
基準電位を設けておき、発振開始より超音波の受
信波形とこの基準電位を比較し、超音波の受信波
形が基準電位以上となる時までの時間Ｔにより距
離を算出していた。Conventional technology As shown in Fig. 4, in a conventional device of this kind, one reference potential is provided, and the received ultrasonic waveform is compared with this reference potential from the start of oscillation, so that the received ultrasonic waveform is at the reference potential. The distance was calculated based on the time T until the above.
発明が解決しようとする問題点
しかしながら、従来の方式では距離測定の精度
が悪いものであつた。第５図に基づき説明する
と、波形Ａは、被測定面がほぼ平面の場合、波形
Ｂは被測定面が凸凹になつている場合を示す（た
だし、波形Ａも波形Ｂも被測定面までの距離は同
じ）。被測定面が凸凹の場合は超音波が反射する
時に散乱してしまい、受信波形が減衰してしまう
ので、波形Ｂのようになる。波形Ａと波形Ｂを同
一基準電位（Vref）で比較した場合、発振開始よ
り、受信電圧が基準電位以上となる時間は、波形
Ａの場合はTA、波形Ｂの場合はTBとなつている。
このように被測定面までの距離は同じであるの
に、受信波形のレベルの差によつて、TAとTBの
差がきてしまい、距離測定の精度が悪い。Problems to be Solved by the Invention However, the accuracy of distance measurement was poor in the conventional method. To explain based on Fig. 5, waveform A shows the case where the surface to be measured is almost flat, and waveform B shows the case where the surface to be measured is uneven (however, both waveform A and waveform B show the distance to the surface to be measured. distance is the same). If the surface to be measured is uneven, the ultrasonic waves will be scattered when reflected and the received waveform will be attenuated, resulting in a waveform like B. When comparing waveform A and waveform B at the same reference potential (V ref ), the time from the start of oscillation until the received voltage exceeds the reference potential is T A for waveform A and T B for waveform B. ing.
In this way, even though the distance to the surface to be measured is the same, there is a difference between T A and T B due to the difference in the level of the received waveform, resulting in poor distance measurement accuracy.
本発明はこのような従来の問題を解決したもの
であり、被測定面の状態いかんにかかわらず、正
確な測定を測定することができる洗濯機の超音波
式距離装置を提供するものである。 The present invention solves these conventional problems and provides an ultrasonic distance measuring device for washing machines that can accurately measure regardless of the condition of the surface to be measured.
問題点を解決するための手段
本発明は上記目的を達成するために、洗濯物と
水とをなじませた状態時に超音波送信器を駆動す
る発振手段と、この発振手段により発射した超音
波が洗濯物または水面に反射してくる超音波を受
信する超音波受信器と、この超音波受信器の出力
を増幅する増幅手段と、この増幅手段の出力と第
１基準電位とを比較する第１比較手段と、前記増
幅手段の出力と第２基準電位とを比較する第２比
較手段と、前記発振手段の発振開始より計時を開
始し、前記第１比較手段の出力により計時を終了
する第１計数手段と、前記発振手段の発振開始よ
り計時を開始し、前記第２比較手段の出力により
計時を終了する第２計数手段と、この第２計数手
段と前記第１計数手段の計時した値を入力し、超
音波受信波形の立ち上がる時点を演算する距離算
出手段と、複数箇所の測定値を統計処理する制御
手段とを有する構成としている。Means for Solving the Problems In order to achieve the above object, the present invention provides an oscillation means for driving an ultrasonic transmitter when laundry and water are mixed together, and an ultrasonic wave emitted by the oscillation means. an ultrasonic receiver that receives ultrasonic waves reflected from laundry or water surfaces, an amplifying means that amplifies the output of the ultrasonic receiver, and a first reference potential that compares the output of the amplifying means with a first reference potential. a comparing means, a second comparing means for comparing the output of the amplifying means and a second reference potential, and a first comparing means that starts timing when the oscillating means starts oscillating and ends timing when the output of the first comparing means starts. a counting means; a second counting means that starts time counting when the oscillation means starts oscillating; and a second counting means that starts time counting when the oscillation means starts and ends the time counting according to the output of the second comparing means; The apparatus is configured to include a distance calculating means for calculating the rise point of the received ultrasonic waveform, and a control means for statistically processing the measured values at a plurality of locations.
作 用
本発明は上記した構成により、受信波形のレベ
ルが違つても立ち上がる点は同じであることを利
用して、正確な距離を得るものである。Effects The present invention uses the above-described configuration to obtain an accurate distance by utilizing the fact that the rising point is the same even if the level of the received waveform is different.
実施例
第１図は本発明の洗濯機の超音波式距離装置の
一実施例を示すブロツク図である。本実施例で
は、洗濯機の上方より洗濯物までの距離を測定す
る超音波距離装置について述べる。１は超音波送
信器で、洗濯物１６あるいは水面に向けて超音波
を発射する。２は超音波受信器で、前記超音波送
信器１より発射した超音波が洗濯物１６あるいは
水面にあたつて反射してくる超音波を受信する。
３は発振手段で、前記超音波送信器１を駆動す
る。４は増幅手段で、前記超音波受信器２の出力
を増幅する。６は第１比較手段で、前記増幅手段
４の出力と第１基準電位５とを比較し、前記増幅
手段４の出力が前記第１基準電位５以上の場合に
制御信号を出力する。８は第２比較手段で、前記
増幅手段４の出力と第２基準電位７とを比較し、
前記増幅手段４の出力が前記第２基準電位７以上
の場合に制御信号を出力する。９，１０は第１計
数手段及び第２計数手段で、前記第１比較手段６
及び前記第２比較手段８より制御信号が出力され
た時に、それぞれ計数を停止し、計数値を出力す
る。１１は距離算出手段で、前記第１計数手段９
と前記第２計数手段１０の計数値より洗濯物１６
あるいは水面までの距離を算出する。１２は制御
手段で、給水手段１３を動作させて、洗濯槽１４
に一定水位まで給水し、かくはん翼１５を一定時
間動作させて水と洗濯物１６をなじませてから、
前記発振手段３を動作させると同時に前記第１計
数手段９、前記第２計数手段１０の計数をスター
トさせる。Embodiment FIG. 1 is a block diagram showing an embodiment of the ultrasonic distance device for a washing machine according to the present invention. In this embodiment, an ultrasonic distance device that measures the distance to laundry from above a washing machine will be described. Reference numeral 1 denotes an ultrasonic transmitter, which emits ultrasonic waves toward the laundry 16 or the water surface. Reference numeral 2 denotes an ultrasonic receiver which receives ultrasonic waves emitted from the ultrasonic transmitter 1 that are reflected when they hit the laundry 16 or the water surface.
Reference numeral 3 denotes an oscillating means for driving the ultrasonic transmitter 1. 4 is an amplifying means for amplifying the output of the ultrasonic receiver 2. Reference numeral 6 denotes first comparing means, which compares the output of the amplifying means 4 and the first reference potential 5, and outputs a control signal when the output of the amplifying means 4 is higher than the first reference potential 5. 8 is a second comparing means, which compares the output of the amplifying means 4 and the second reference potential 7;
When the output of the amplifying means 4 is higher than the second reference potential 7, a control signal is output. 9 and 10 are a first counting means and a second counting means, and the first comparing means 6
And when a control signal is output from the second comparing means 8, counting is stopped and the counted value is output. 11 is a distance calculation means, and the first counting means 9
From the count value of the second counting means 10, the laundry 16
Or calculate the distance to the water surface. 12 is a control means that operates the water supply means 13 to supply the washing tub 14;
After supplying water to a certain water level and operating the stirring blades 15 for a certain period of time to mix the water and laundry 16,
At the same time as the oscillation means 3 is operated, the first counting means 9 and the second counting means 10 start counting.
第２図に本発明の一実施例における具体的な回
路図を示す。超音波送信器１及び超音波受信器２
は、超音波マイクロフオンで構成される。発振手
段３は、インバータゲートIC３０１〜IC３０３、
抵抗R301〜R308、トンラジスタＱ３０１〜Ｑ３
０３、コンデンサＣ３０１、昇圧トランスＴ３０
１より構成される。増幅手段４は、演算増幅器
IC４０１〜IC４０２、抵抗R401〜R407、コンデ
ンサＣ４０１〜Ｃ４０３により構成される。第１
基準電位５は、抵抗R501、R502により構成され
る。第１比較手段６は、比較器IC６０１、抵抗
R601により構成される。第２基準電位７は、抵
抗R701、R702により構成される。第２比較手段
８は比較器IC８０１、抵抗R801により構成され
る。第１係数手段９、第２係数手段１０、距離算
出手段１１、制御手段１２は、マイクロコンピユ
ーター１７により構成される。給水手段１３は、
抵抗R131、トランジスタＱ１３１、ダイオード
１３１、リレーRL１３１、給水弁Ｋ１３１によ
り構成される。 FIG. 2 shows a specific circuit diagram in one embodiment of the present invention. Ultrasonic transmitter 1 and ultrasonic receiver 2
consists of an ultrasonic microphone. The oscillation means 3 includes inverter gates IC301 to IC303,
Resistor R301~R308, resistance resistor Q301~Q3
03, capacitor C301, step-up transformer T30
Consists of 1. The amplifying means 4 is an operational amplifier.
It is composed of IC401-IC402, resistors R401-R407, and capacitors C401-C403. 1st
The reference potential 5 is composed of resistors R501 and R502. The first comparing means 6 includes a comparator IC601, a resistor
Constructed by R601. The second reference potential 7 is composed of resistors R701 and R702. The second comparison means 8 is composed of a comparator IC801 and a resistor R801. The first coefficient means 9, the second coefficient means 10, the distance calculation means 11, and the control means 12 are constituted by a microcomputer 17. The water supply means 13 is
It is composed of a resistor R131, a transistor Q131, a diode 131, a relay RL131, and a water supply valve K131.
上記の様に構成された超音波式距離装置の作用
について述べる。 The operation of the ultrasonic distance device configured as described above will be described.
洗濯槽１４に洗濯物１６を入れ使用者が洗濯を
開始すると、制御手段１２は、給水手段１３を動
作させ一定水位まで給水させる。給水が終了する
と、かくはん翼１５を一定時間動作させて水と洗
濯物を充分になじませる。これは洗濯物が水面よ
り部分的に飛び出ていて、洗濯物までの本当の距
離が計れないのを防止するためである。また制御
手段１２は、発振手段３を動作させて超音波送信
器１より超音波を発信させる。同時に第１計数手
段９、第２計数手段１０の計時を開始させる。次
に超音波受信器２は、洗濯物１６あるいは水面に
あたつて反射してくる超音波を受信し、増幅手段
４によりこれを増幅する。その波形を第３図の
Ａ，Ｂに示す。第３図Ａは、水面あるいは洗濯物
面がフラツトな状態のところで反射してくる超音
波の波形で、第３図Ｂは、先濯物面が山状になつ
たり波形になつたりする場合である。実際洗濯す
る場合はＢの方が多くみられるものである。 When the user puts the laundry 16 into the washing tub 14 and starts washing, the control means 12 operates the water supply means 13 to supply water up to a certain water level. When the water supply is finished, the stirring blades 15 are operated for a certain period of time to mix the water and the laundry sufficiently. This is to prevent the laundry from partially protruding from the water surface and making it impossible to measure the true distance to the laundry. The control means 12 also operates the oscillation means 3 to cause the ultrasonic transmitter 1 to emit ultrasonic waves. At the same time, the first counting means 9 and the second counting means 10 are started to measure time. Next, the ultrasonic receiver 2 receives the ultrasonic waves reflected from the laundry 16 or the water surface, and the amplifying means 4 amplifies the ultrasonic waves. The waveforms are shown in A and B of FIG. Figure 3A shows the waveform of the ultrasonic wave reflected when the water surface or laundry surface is flat, and Figure 3B shows the waveform when the laundry surface is mountain-like or wave-like. be. When actually doing laundry, type B is more common.
ここで、第１比較手段６により増幅された超音
波受信波形と、第１基準電位５（図示ではVref1）
を比較し、増幅された超音波受信波形の方が
Vref1以上となつた時、第１計数手段９の計数値
は第３図ＡではT1、同ＢではT3となつている。
また同様に、第２比較手段８により増幅された超
音波受信波形と第２基準電位７を比較しVref2以
上となつた時、第２計数手段１０の計数値は、第
３図ＡではT2、同ＢではT4となつている。距離
算出手段１１は、このT1あるいはT3，T2あるい
はT4を入力し、式Ａにより、超音波受信波形が
立上る時点（洗濯物あるいは水面までの距離）
T0を算出する。 Here, the ultrasonic reception waveform amplified by the first comparing means 6 and the first reference potential 5 (V ref1 in the figure)
The amplified ultrasonic reception waveform is
When V ref1 or more is reached, the count value of the first counting means 9 is T 1 in FIG. 3A and T 3 in FIG. 3B.
Similarly, when the ultrasonic reception waveform amplified by the second comparison means 8 and the second reference potential 7 are compared and the voltage exceeds V ref2 , the count value of the second counting means 10 is T in FIG. 3A. 2 , it is T 4 in the same B. The distance calculation means 11 inputs this T 1 or T 3 , T 2 or T 4 and calculates the point at which the received ultrasonic waveform rises (distance to the laundry or the water surface) using equation A.
Calculate T 0 .
T0＝TVref2
−（Vref2TVref2−TVref1／Vref2−Vref1） ……Ａ
従つて洗濯物あるいは水面までの距離L0は
L0＝Ｃ×T0／２
Ｃ：音速
となる。この距離測定を洗濯槽１４の複数個所で
行ない、これを制御手段１２で統計処理して現在
の距離を正確に把握し、次の水位、水流を決定し
洗濯行程に移る。T 0 = T Vref2 - (V ref2 T Vref2 - T Vref1 /V ref2 - V ref1 ) ...A Therefore, the distance L 0 to the laundry or the water surface is L 0 = C x T 0 /2 C: The speed of sound . This distance measurement is performed at a plurality of locations in the washing tub 14, and this is statistically processed by the control means 12 to accurately grasp the current distance, determine the next water level and water flow, and proceed to the washing process.
発明の効果
上記実施例から明らかなように本発明の洗濯機
の超音波式距離装置は、洗濯物と水とをなじませ
た状態時に超音波送信器を駆動する発振手段と、
この発振手段により発射した超音波が洗濯物また
は水面に反射してくる超音波を受信する超音波受
信器と、この超音波受信器の出力を増幅する増幅
手段と、この増幅手段の出力と第１基準電位とを
比較する第１比較手段と、前記増幅手段の出力と
第２基準電位とを比較する第２比較手段と、前記
発振手段の発振開始より計時を開始し、前記第１
比較手段の出力により計時を終了する第１計数手
段と、前記発信手段の発振開始より計時を開始し
前記第２比較手段の出力により計時を終了する第
２計数手段と、この第２計数手段と前記第１計数
手段の計時した値を入力し、超音波受信波形の立
ち上がる時点を演算する距離算出手段と、複数箇
所の測定値を統計処理する制御手段とを有するも
のであり、この構成とすることにより、距離を測
定する面に凹凸があり受信波形が減衰しても、正
確な距離を測定することができる。Effects of the Invention As is clear from the above embodiments, the ultrasonic distance device for a washing machine of the present invention includes an oscillation means that drives an ultrasonic transmitter when laundry and water are mixed together;
an ultrasonic receiver that receives the ultrasonic waves emitted by the oscillation means and reflected on the laundry or the water surface; an amplification means that amplifies the output of the ultrasonic receiver; a first comparison means for comparing the output of the amplification means with a second reference potential; a second comparison means for comparing the output of the amplification means with a second reference potential;
a first counting means that terminates timekeeping according to the output of the comparison means; a second counting means that starts timekeeping when the oscillation of the transmitting means starts and ends the timekeeping according to the output of the second comparison means; It has a distance calculation means for inputting the timed value of the first counting means and calculating the rising point of the ultrasonic reception waveform, and a control means for statistically processing the measured values at a plurality of locations, and has this configuration. This makes it possible to accurately measure the distance even if the surface on which the distance is to be measured is uneven and the received waveform is attenuated.
第１図は本発明の一実施例における洗濯機の超
音波式距離装置を示すブロツク図、第２図は本発
明の一実施例における洗濯機の超音波式距離装置
を示す回路図、第３図Ａ，Ｂはそれぞれ異なる測
定面における２つの基準電位と受信波形の関係を
示す図、第４図は従来の洗濯機の超音波式距離装
置の基準電位と受信波形を示す図、第５図は従来
装置による異なる測定面とその受信波形を示す図
である。
１……超音波送信器、２……超音波受信器、３
……発振手段、４……増幅手段、５……第１基準
電位、６……第１比較手段、７……第２基準電
位、８……第２比較手段、９……第１計数手段、
１０……第２計数手段、１１……距離算出手段、
１２……制御手段、１３……給水手段、１４……
洗濯槽、１５……かくはん翼、１６……洗濯物、
１７……マイクロコンピユーター。
FIG. 1 is a block diagram showing an ultrasonic distance device for a washing machine according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing an ultrasonic distance device for a washing machine according to an embodiment of the present invention, and FIG. Figures A and B are diagrams showing the relationship between two reference potentials and received waveforms on different measurement planes, Figure 4 is a diagram showing the reference potential and received waveform of a conventional ultrasonic distance device for a washing machine, and Figure 5 is a diagram showing the relationship between two reference potentials and received waveforms on different measurement surfaces. FIG. 2 is a diagram showing different measurement planes and their received waveforms by a conventional device. 1... Ultrasonic transmitter, 2... Ultrasonic receiver, 3
...Oscillating means, 4...Amplifying means, 5...First reference potential, 6...First comparison means, 7...Second reference potential, 8...Second comparison means, 9...First counting means ,
10... second counting means, 11... distance calculating means,
12... Control means, 13... Water supply means, 14...
Washing tub, 15...Agitating wing, 16...Laundry,
17...Microcomputer.
Claims (1)
信器を駆動する発振手段と、この発振手段により
発射した超音波が洗濯物または水面に反射してく
る超音波を受信する超音波受信器と、この超音波
受信器の出力を増幅する増幅手段と、この増幅手
段の出力と第１基準電位とを比較する第１比較手
段と、前記増幅手段の出力と第２基準電位とを比
較する第２比較手段と、前記発振手段の発振開始
より計時を開始し、前記第１比較手段の出力によ
り計時を終了する第１計数手段と、前記発振手段
の発振開始より計時を開始し前記第２比較手段の
出力により計時を終了する第２計数手段と、この
第２計数手段と前記第１計数手段の計時した値を
入力し、超音波受信波形の立ち上がる時点を演算
する距離算出手段と、複数箇所の測定値を統計処
理する制御手段とを有する洗濯機の超音波式距離
装置。1. An oscillating means that drives an ultrasonic transmitter when the laundry and water are mixed together, and an ultrasonic receiver that receives the ultrasonic waves emitted by the oscillating means and reflected on the laundry or the water surface. an amplification means for amplifying the output of the ultrasonic receiver; a first comparison means for comparing the output of the amplification means with a first reference potential; and a comparison means for comparing the output of the amplification means with a second reference potential. a second comparing means; a first counting means that starts measuring time when the oscillating means starts oscillating; and a first counting means that starts measuring time when the oscillating means starts oscillating; and a second counting means that starts measuring time when the oscillating means starts oscillating; a second counting means for terminating time counting by the output of the comparison means; a distance calculating means for inputting the timed values of the second counting means and the first counting means and calculating a rising point of the ultrasonic reception waveform; An ultrasonic distance device for a washing machine, comprising a control means for statistically processing measured values at a location.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20922285A JPS6267481A (en) | 1985-09-20 | 1985-09-20 | Ultrasonic type distance measuring apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20922285A JPS6267481A (en) | 1985-09-20 | 1985-09-20 | Ultrasonic type distance measuring apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6267481A JPS6267481A (en) | 1987-03-27 |
| JPH045355B2 true JPH045355B2 (en) | 1992-01-31 |
Family
ID=16569370
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20922285A Granted JPS6267481A (en) | 1985-09-20 | 1985-09-20 | Ultrasonic type distance measuring apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6267481A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2016080651A (en) * | 2014-10-22 | 2016-05-16 | 株式会社デンソー | Reception time estimation device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5997069A (en) * | 1982-11-25 | 1984-06-04 | Nissan Motor Co Ltd | Ultrasonic car height measuring apparatus |
| JPS6025982U (en) * | 1983-07-27 | 1985-02-21 | フアナツク株式会社 | ultrasonic distance sensor |
-
1985
- 1985-09-20 JP JP20922285A patent/JPS6267481A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6267481A (en) | 1987-03-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |