JPS6141970A - Air speed indicator - Google Patents

Air speed indicator

Info

Publication number
JPS6141970A
JPS6141970A JP16281884A JP16281884A JPS6141970A JP S6141970 A JPS6141970 A JP S6141970A JP 16281884 A JP16281884 A JP 16281884A JP 16281884 A JP16281884 A JP 16281884A JP S6141970 A JPS6141970 A JP S6141970A
Authority
JP
Japan
Prior art keywords
air
blower
wind speed
speed
wind
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.)
Pending
Application number
JP16281884A
Other languages
Japanese (ja)
Inventor
Katsumi Chiba
千葉　克実
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Priority to JP16281884A priority Critical patent/JPS6141970A/en
Publication of JPS6141970A publication Critical patent/JPS6141970A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
    • G01P5/14—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring differences of pressure in the fluid
    • G01P5/16—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring differences of pressure in the fluid using Pitot tubes, e.g. Machmeter
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
    • G01P5/02—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring forces exerted by the fluid on solid bodies, e.g. anemometer
    • G01P5/06—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring forces exerted by the fluid on solid bodies, e.g. anemometer using rotation of vanes

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Instrument Panels (AREA)

Abstract

PURPOSE:To indicate the air wind speed at the time of low air wind speed by selecting air speed values converted from number of rotations of an air blower when the number of rotations of the blower is low rotational frequencies and selecting measured values of air speed measured by an air speedometer when the number of rotation is larger than it. CONSTITUTION:Total pressure and static pressure are detected by an air speedometer when a blower driving electric motor 12 is driven to rotate blades of an air blower 11 and wind of necessary air speed is generated in a measuring section 13. The detection signal is led to a differential pressure converter 15, and differential pressure (dynamic pressure) is converted to electric signals and inputted to a switching circuit 20 through a signal conditioner 16 and an A/D converter 17. On the other hand, the number of rotations of blades of the air blower 11 is detected by a pulse generator 18 attached to the electric motor 12 as a pulse train, and converted to an air speed value by an arithmetic circuit 19 through a counter and inputted to the circuit 20. The circuit 20 makes conversion of physical quantity based on each input signal and selects air speed values converted from the number of rotations of the blower, and when in excess of it, selects measured values of wind speed measured by the air speedometer, and sends to an indicator 21.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は送風機の羽根の回転により発生する風の風速を
表示する風の風速表示装置の改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a wind speed display device that displays the speed of wind generated by the rotation of blades of a blower.

（従来の技術） 聾来の前記風の風速表示装置を第３図により説明すると
、（１）が送風機、（２）が送風機駆動電動機、（３）
が測定部、（４）が送風機（１）の羽根の回転により発
生する風の風速を計測する風速計（例えばピトー管）　
、　（５）が差圧変換器、（６）がシグナルコンデシツ
ナ、（７）が開平演算器９（８）がデジタルボルトメー
タで、送風機駆動電動機（２）を駆動し、送風機（１）
の羽根を回転して、測定部（３）に必要な風速の風を発
生させときに、風速計（４）により全圧及び静圧を検出
し、そのとき得られた検出信号を差圧変換器（５）へ導
いて、差圧（動圧）を電気信号に変換する。このとき、
シグナルコンデシツナ（６）は、差圧変換器（５）へ電
流を供給するとともに、上記電気信号を増幅して、開平
演算器（７）へ送る。同開平演算器（７）；ま、同＋！
輻した電気信号（動圧信号）を風速に比例した信号に変
換し、デジタルボルトメータ（８）へ送って。(Prior Art) The conventional wind speed display device will be explained with reference to FIG. 3. (1) is a blower, (2) is a blower driving electric motor, and (3) is a blower.
is the measurement part, and (4) is an anemometer (for example, a pitot tube) that measures the wind speed generated by the rotation of the blades of the blower (1).
, (5) is a differential pressure converter, (6) is a signal conditioner, (7) is a square root calculator 9 (8) is a digital voltmeter, which drives the blower drive motor (2), and the blower (1).
When rotating the blades to generate wind at the required wind speed in the measuring section (3), the anemometer (4) detects the total pressure and static pressure, and the detection signal obtained at that time is converted into differential pressure. (5) to convert the differential pressure (dynamic pressure) into an electrical signal. At this time,
The signal conditioner (6) supplies current to the differential pressure converter (5), amplifies the electrical signal, and sends it to the square root calculator (7). Same square root operator (7); Well, same +!
The radiating electric signal (dynamic pressure signal) is converted into a signal proportional to wind speed and sent to the digital voltmeter (8).

風速を表示するようになっている。It is designed to display wind speed.

（発明が解決しようとする問題点） 前記風の風速表示装置では、５〜６ｍ／ｓ以上の風の計
測は正確におこなうが、それ以下の風の計測は、風速計
（４）及び差圧検出器（５）の誤差等により正確に行う
ことができない、また第４図に示すように差圧（動圧）
ΔＰ　（ｍ＋ｏＡｇ）が風速Ｖ（ｍ／ｓ）の２乗に比例
するので、差圧誤差による風速誤差が非常に大きくなり
、殆ど無風時でも。(Problems to be Solved by the Invention) The wind speed display device described above accurately measures winds of 5 to 6 m/s or more, but measures winds of less than 5 to 6 m/s using an anemometer (4) and differential pressure. Accurate measurement may not be possible due to errors in the detector (5), or differential pressure (dynamic pressure) as shown in Figure 4.
Since ΔP (m+oAg) is proportional to the square of the wind speed V (m/s), the wind speed error due to differential pressure error becomes very large, even when there is almost no wind.

差圧変換器（５）の誤差等により３〜４　ｍ　／　ｓの
風速を表示するという欠点があった。なお第５図は、送
風機（１）の回転数Ｎ　（ｒｐｍ）と測定部（３）の風
速との関係を示しており、これらは殆ど比例関係にある
。There was a drawback that a wind speed of 3 to 4 m/s was displayed due to errors in the differential pressure converter (5). Note that FIG. 5 shows the relationship between the rotational speed N (rpm) of the blower (1) and the wind speed of the measuring section (3), which are almost in a proportional relationship.

（問題点を解決するための手段） 本発明は前記の欠点を除去するもので、送風機の羽根の
回転により発生する風の風速を表示する風の風速表示装
置において、風速を計測する風速計と、前記送風機の羽
根の回転数を検出する回転数検出器と、同回転数検出器
の出方を風速に変換する演算回路と、同演算回路からの
入力が一定値以下のときにはその入力を出力しそれ以外
のときには上記風速計からの入力を出方する切換回路と
同切換回路からの入力を受けて風速を表示する表示器と
を具えていることを特徴とした風の風速表示装置に係わ
り、その目的とする処は、低風速時の風速を正確に表示
することができる改良された風の風速表示装置を供する
点にある。(Means for Solving the Problems) The present invention eliminates the above-mentioned drawbacks, and includes a wind speed display device that displays the wind speed of the wind generated by the rotation of the blades of a blower. , a rotation speed detector that detects the rotation speed of the blades of the blower, an arithmetic circuit that converts the output of the rotation speed detector into wind speed, and an output of the input when the input from the arithmetic circuit is below a certain value. At other times, the present invention relates to a wind speed display device characterized by comprising a switching circuit that outputs the input from the anemometer and a display that receives the input from the switching circuit and displays the wind speed. , its object is to provide an improved wind speed display device that can accurately display wind speed at low wind speeds.

（実施例） 次に本発明の風の風速表示装置を第１図に示す一実施例
により説明すると、　（１１）がが送風機、（１２）が
送風機駆動電動機、　（１３）が測定部、　（１４）が
送風機（１）の羽根の回転により発生する風の風速を計
測する風速計（例えばピトー管）　、　（１５）が差圧
変換器、　（１６）がシグナルコンデシコナ、　（１７
）がＡ／Ｄ変換器で、同Ａ／Ｄ変換器（１７）は、電気
信号（アナログ信号）をデジタル信号に変換して、切換
回路（２０）へ入力するようになっしている。一方、送
風機（１１）の羽根の回転数は、送風機駆動電動機（１
２）に取り付けたパルスジェネレータ（１８）によりパ
ルス列として検出され、それがカウンタ（１８゜）へ送
られて、カウントされ、演算回路（１９）により風速値
に換算されて、切換回路（２０）へ入力されるようにな
っている。また風速計（１４）が計測した風速の測定精
度を向上するために、温度検出器（図示せず）からの気
流温度信号を入力して、風速演算時の気流温度の違いに
よる補正を行うようになっている。また上記切換回路（
２０）は、上記各入力信号に基づいて物理量の換算を行
い、送風機（１１）の回転数が低回転数域（例えば２Ｏ
ｒｐｍ）のときには、送風機（１１）の回転数から換算
した風速値を。(Example) Next, the wind speed display device of the present invention will be described with reference to an example shown in FIG. 14) is an anemometer (for example, a pitot tube) that measures the wind speed generated by the rotation of the blades of the blower (1), (15) is a differential pressure converter, (16) is a signal conditioner, (17)
) is an A/D converter, and the A/D converter (17) converts an electric signal (analog signal) into a digital signal and inputs it to the switching circuit (20). On the other hand, the rotation speed of the blades of the blower (11) is
2) is detected as a pulse train by the pulse generator (18) installed in It is now entered. In addition, in order to improve the measurement accuracy of the wind speed measured by the anemometer (14), an airflow temperature signal from a temperature detector (not shown) is input, and corrections due to differences in airflow temperature are performed when calculating the wind speed. It has become. In addition, the above switching circuit (
20) converts physical quantities based on each of the above input signals, and determines whether the rotation speed of the blower (11) is in a low rotation speed range (for example, 2O
rpm), the wind speed value is calculated from the rotation speed of the blower (11).

またそ、れ以上のときには、風速計（１４）が計測した
風速の測定値を、それぞれ選択して１表示器（２１）へ
送るようになっている。In addition, when the wind speed exceeds that point, the measured values of the wind speed measured by the anemometer (14) are selected and sent to the 1 display (21).

（作用） 次に前記風の風速表示装置の作用を説明する。(effect) Next, the operation of the wind speed display device will be explained.

送風機駆動電動機（１２）を駆動し、送風機（１１）の
羽根を回転して、測定部（１３）に必要な風速の風を発
生させときに、風速計（１４）により全圧及び静圧を検
出し、そのとき得られた検出信号を差圧変換器（１５）
へ導いて、差圧（動圧）を電気信号に変換する。またこ
の電気信号をシグナルコンデショナ（１６）を経て同Ａ
／Ｄ変換器（１７）へ送り、ここでは。When driving the blower drive electric motor (12) and rotating the blades of the blower (11) to generate wind at the required wind speed for the measuring section (13), the anemometer (14) measures the total pressure and static pressure. The detection signal obtained at that time is sent to a differential pressure converter (15).
to convert the differential pressure (dynamic pressure) into an electrical signal. In addition, this electrical signal is passed through the signal conditioner (16)
/D converter (17), here.

電気信号（アナログ信号）をデジタル信号に変換して、
切換回路（２０）へ入力する。一方、送風機（１１）の
羽根の回転数は、送風機駆動電動機（１２）に取り付け
たパルスジェネレータ（１８）によりパルス列として検
出され、それがカウンタ（１８°）へ送られて、カウン
トされ、演算回路（１９）により風速値に換算されて、
切換回路（２０）へ入力される。同切換回路（２０）は
、上記各入力信号に基づいて物理量の換算を行い、送風
機（１１）の回転数が低回転数域（例えば２０ｒｐｍ）
のときには、送風機（１１）の回転数から換算した風速
値を、またそれ以上のときには。Convert electrical signals (analog signals) to digital signals,
Input to the switching circuit (20). On the other hand, the number of rotations of the blades of the blower (11) is detected as a pulse train by the pulse generator (18) attached to the blower drive motor (12), which is sent to a counter (18°) and counted, and then (19) is converted into a wind speed value,
It is input to the switching circuit (20). The switching circuit (20) converts physical quantities based on each of the above input signals, and determines that the rotation speed of the blower (11) is in a low rotation speed range (for example, 20 rpm).
When , the wind speed value is calculated from the rotation speed of the blower (11), and when it is higher than that.

風速計（１４）が計測した風速の測定値を、それぞれ選
択して１表示器（２１）へ送る。The wind speed measurements measured by the anemometer (14) are selected and sent to the 1 display (21).

（発明の効果） 本発明は前記のように送風機の羽根の回転により発生ず
る風の風速を表示する風の風速表示装置において、風速
を計測する風速計と、前記送風機の羽根の回転数を検出
する回転数検出器と、同回転数検出器の出力を風速に変
換する演算回路と。(Effects of the Invention) As described above, the present invention provides a wind speed display device that displays the wind speed of the wind generated by the rotation of the blades of a blower, including an anemometer that measures the wind speed and a wind speed meter that detects the rotational speed of the blades of the blower. and a calculation circuit that converts the output of the rotation speed detector into wind speed.

同演算回路からの入力が一定値以下のときにはその入力
を出力しそれ以外のときには上記風速計からの入力を出
力する切換回路と、同切換回路からの入力を受けて風速
を表示する表示器とを具えていて、前記の作用が行われ
るので９次の効果を達成できる。即ち、低風速域の風速
値を送風機の回転数に置き換えているが、その理由は３
次の通りである。■送風機の回転数が測定部の風速に比
例する。■胴内の圧力損失（例えば測定部内に設置した
物体により生じる圧力損失）が異なっても。a switching circuit that outputs the input when the input from the arithmetic circuit is below a certain value, and otherwise outputs the input from the anemometer; and a display that receives the input from the switching circuit and displays the wind speed. Since the above-mentioned action is performed, the ninth-order effect can be achieved. In other words, the wind speed value in the low wind speed range is replaced with the rotation speed of the blower, and the reason for this is 3.
It is as follows. ■The rotation speed of the blower is proportional to the wind speed at the measuring section. ■Even if the pressure loss inside the shell (for example, the pressure loss caused by an object installed in the measuring section) is different.

低風速域における風速値の送風機回転数に対する絶対誤
差が少ない、上記■については、第５図のところで既に
説明した通りである。また上記■についての送風機回転
数と測定部風速との関係については、第２図に示す通り
である。同第２図において、（ａ）〜（ｃ）は、測定胴
内に設置した物体の圧力損失の違いによる送風機回転数
と測定部風速との特性曲線である。ここで、送風機回転
数が定格速度Ｎ　ｏ　（ｒｐｓ）においては、各（ａ）
　〜（ｃ）状態時の風速誤差が例えば（ｂ）の場合を基
準にとると、ΔＶａ及びΔＶｃになり、誤差は大きいが
、低回転域（例えばＮｌｒｐｍ）における誤差は、ΔＶ
ａ’になり、誤差の絶対値が小さい、このことにより、
（ｂ）の場合の回転数を基準として低風速域の風速値を
送１−機回転数に比例させて１表示しても。The above-mentioned item (2), in which the absolute error of the wind speed value with respect to the fan rotation speed in the low wind speed region is small, is as already explained in FIG. 5. Furthermore, the relationship between the blower rotation speed and the wind speed at the measuring section regarding the above item (2) is as shown in FIG. In FIG. 2, (a) to (c) are characteristic curves of the blower rotational speed and the measuring section wind speed due to differences in pressure loss of objects installed in the measuring barrel. Here, when the blower rotation speed is the rated speed N o (rps), each (a)
~ (c) If the wind speed error in the state (b) is taken as a standard, it becomes ΔVa and ΔVc, and the error is large, but the error in the low rotation range (for example, Nlrpm) is ΔV
a', and the absolute value of the error is small. Due to this,
Even if the wind speed value in the low wind speed region is expressed as 1 in proportion to the feeder rotation speed, using the rotation speed in the case of (b) as a reference.

実用上に問題はない。また送風機回転数Ｏｒｐｍにおい
て風速値は必ずＱ　ｍ　／　ｓになり、計測器の誤差に
影響されなくなる。従って本発明によれば、低風速時の
風速を正確に表示することができる効果がある。There is no problem in practical use. Further, at the blower rotation speed Orpm, the wind speed value is always Q m /s, and is not affected by the error of the measuring instrument. Therefore, according to the present invention, it is possible to accurately display the wind speed at low wind speeds.

以上本発明を実施例ついて説明したが、勿論本発明はこ
のような実施例にだけ局限されるものではなく１本発明
の精神を逸脱しない範囲で種々の設計の改変を施しうる
ものである。Although the present invention has been described above with reference to embodiments, it is needless to say that the present invention is not limited to these embodiments, and can be modified in various ways without departing from the spirit of the present invention.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明に係わる風の風速表示装置の一実施例を
示す系統図、第２図は送風機回転数と測定部風速との関
係を示す説明図、第３図は従来の風の風速表示装置を示
す系統図、第４図は差圧（動圧）ΔＰ　（ｍｍＡｇ）と
風速Ｖ　（ｍ　／ｓ　）との関係を示す説明図、第５図
は送風機（１）の回転数Ｎ（ｒｐｎ＋）と測定部（３）
の風速との関係を示す説明図である。 （１１）・・・送風機、　（１３）　　・・・風速針、
　（１Ｂ）　　・・・回転数検出器、　（１９）　　・
・・演算回路、　（２０）　　・・・切換回路、　（２
１）　　・・・表示器。 復代理人弁理士岡本重文外３名 第１０ 第２０Fig. 1 is a system diagram showing an embodiment of the wind speed display device according to the present invention, Fig. 2 is an explanatory diagram showing the relationship between the number of rotations of the blower and the wind speed at the measuring section, and Fig. 3 is a diagram showing the wind speed of the conventional wind. A system diagram showing the display device, Fig. 4 is an explanatory diagram showing the relationship between differential pressure (dynamic pressure) ΔP (mmAg) and wind speed V (m/s), and Fig. 5 shows the rotation speed N (of the blower (1)). rpn+) and measuring section (3)
FIG. 2 is an explanatory diagram showing the relationship between wind speed and (11)...Blower, (13)...Wind speed needle,
(1B) ... Rotation speed detector, (19) ・
...Arithmetic circuit, (20) ...Switching circuit, (2
1) ...Indicator. Sub-Agent Patent Attorney Okamoto Shigemono 3 persons No. 10 No. 20

Claims (1)

【特許請求の範囲】[Claims] 送風機の羽根の回転により発生する風の風速を表示する
風の風速表示装置において、風速を計測する風速計と、
前記送風機の羽根の回転数を検出する回転数検出器と、
同回転数検出器の出力を風速に変換する演算回路と、同
演算回路からの入力が一定値以下のときにはその入力を
出力しそれ以外のときには上記風速計からの入力を出力
する切換回路と、同切換回路からの入力を受けて風速を
表示する表示器とを具えていることを特徴とした風の風
速表示装置。In a wind speed display device that displays the wind speed of the wind generated by the rotation of the blades of a blower, an anemometer that measures the wind speed;
a rotation speed detector that detects the rotation speed of the blades of the blower;
an arithmetic circuit that converts the output of the rotation speed detector into wind speed; and a switching circuit that outputs the input when the input from the arithmetic circuit is below a certain value, and otherwise outputs the input from the anemometer; A wind speed display device comprising: a display device that displays wind speed in response to input from the switching circuit.
JP16281884A 1984-08-03 1984-08-03 Air speed indicator Pending JPS6141970A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP16281884A JPS6141970A (en) 1984-08-03 1984-08-03 Air speed indicator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP16281884A JPS6141970A (en) 1984-08-03 1984-08-03 Air speed indicator

Publications (1)

Publication Number Publication Date
JPS6141970A true JPS6141970A (en) 1986-02-28

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP16281884A Pending JPS6141970A (en) 1984-08-03 1984-08-03 Air speed indicator

Country Status (1)

Country Link
JP (1) JPS6141970A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01102369A (en) * 1987-10-16 1989-04-20 Sanshin Ind Co Ltd Ship speed detector
JPH06193590A (en) * 1992-12-25 1994-07-12 Rinnai Corp Blower disposing device
CN100356176C (en) * 2004-03-15 2007-12-19 清华大学 Minisize low speed airspeedometer for mini aircrafts

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01102369A (en) * 1987-10-16 1989-04-20 Sanshin Ind Co Ltd Ship speed detector
JPH06193590A (en) * 1992-12-25 1994-07-12 Rinnai Corp Blower disposing device
CN100356176C (en) * 2004-03-15 2007-12-19 清华大学 Minisize low speed airspeedometer for mini aircrafts

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