JPH025419Y2

JPH025419Y2 -

Info

Publication number: JPH025419Y2
Application number: JP7887480U
Authority: JP
Priority date: 1980-06-06
Filing date: 1980-06-06
Publication date: 1990-02-08
Also published as: JPS574760U

Description

【考案の詳細な説明】［産業上の利用分野］本考案は電流駆動型の可動鉄片式計器におい
て、駆動回路にオペレーシヨナルアンプを使用す
ることにより、この駆動回路の簡素化をはかり、
かつ、計器の最小点と最大点の組合せが独立して
調整できるようにした計器の駆動回路に関するも
のである。[Detailed description of the invention] [Industrial field of application] The present invention aims to simplify the drive circuit of a current-driven moving iron type instrument by using an operational amplifier in the drive circuit.
The present invention also relates to a meter drive circuit in which the combination of the minimum and maximum points of the meter can be adjusted independently.

［従来の技術］従来、この種の計器の駆動回路としては第３図
に示すような回路があつた。この回路は、まず最
小点調整のために、可変抵抗RV₅とRV₃をともに
最小にしぼり、基準用電源Eiを可変して最小点用
電圧Ei₁を加え、この状態で可変抵抗RV₄を可変
して計器Ｍの指針を最小点に合わせる。そして、
計器Ｍのオン電圧を設定するために、基準用電源
Eiをオン電圧にして、この状態でトランジスタ
Q₃とQ₄がオンとなるまで可変抵抗RV₃を上げる。
さらに最大点調整のために基準用電源Eiを可変し
て最大用電圧Ei₂を加え、この状態で可変抵抗
RV₅を可変して計器Ｍの指針を最大点に合わせ
る。[Prior Art] Conventionally, a circuit as shown in FIG. 3 has been used as a drive circuit for this type of meter. In this circuit, first, to adjust the minimum point, variable resistors RV ₅ and RV ₃ are both minimized, the reference power supply Ei is varied and minimum point voltage Ei ₁ is applied, and in this state, variable resistor RV ₄ is adjusted. Adjust the pointer of the meter M to the minimum point. and,
In order to set the on-voltage of meter M, the reference power supply
Set Ei to the on voltage, and in this state the transistor
Increase variable resistor RV ₃ until Q ₃ and Q ₄ turn on.
Furthermore, in order to adjust the maximum point, the reference power supply Ei is varied and the maximum voltage Ei ₂ is added, and in this state, the variable resistor is
Adjust RV ₅ to set the pointer of instrument M to the maximum point.

［考案が解決しようとする課題］前記従来の駆動回路は、目盛合せにおいて、最
小点に調整すると、最大点に影響して狂いが生
じ、逆に最大点を調整すると、最小点に影響を与
え、したがつて、最小点と最大点をいずれも正確
に一致させるには、何回もの調整を必要とし、極
めて面倒であつた。また、第３図の駆動回路は基
準用電源Eiが1.6V以上でないと計器Ｍが振れな
いので、それ以下で使用する場合は負電源が必要
となる。具体的には、図中の接地Ｇを負電源に接
続することが必要となる。さらに、温度特性が悪
いので、使用温度範囲が広いなど温度特性が問題
となる場合には、温度保証回路を付加する必要が
ある。このように駆動回路の部品点数が増え、複
雑となるなどの問題点があつた。[Problems to be solved by the invention] In the conventional drive circuit, when adjusting the scale, adjusting to the minimum point affects the maximum point and causes a deviation, and conversely, adjusting the maximum point affects the minimum point. , Therefore, in order to accurately match both the minimum point and the maximum point, many adjustments were required, which was extremely troublesome. Further, in the drive circuit shown in FIG. 3, the meter M will not swing unless the reference power source Ei is 1.6 V or higher, so a negative power source is required if the driving circuit is used at a voltage lower than 1.6 V. Specifically, it is necessary to connect the ground G in the figure to a negative power supply. Furthermore, since the temperature characteristics are poor, it is necessary to add a temperature guarantee circuit if the temperature characteristics are a problem, such as when the operating temperature range is wide. In this way, the number of components in the drive circuit increases, and problems arise, such as the complexity of the drive circuit.

本考案は、計器の調整が簡素で、かつ部品点数
が少なく回路構成が極めて簡素であり、しかも負
電源や温度保証回路の必要のない計器の駆動回路
を得ることを目的とする。 The object of the present invention is to provide a driving circuit for a meter that allows simple adjustment of the meter, has a small number of parts, has an extremely simple circuit configuration, and does not require a negative power source or a temperature guarantee circuit.

［課題を解決するための手段］本考案はこのような従来の欠点を解決するため
になされたもので、可動鉄片式計器の駆動回路と
してオペレーシヨナルアンプを使用し、このオペ
レーシヨナルアンプはその利得が１以上になるよ
うに抵抗を接続し、非反転入力側に基準電圧を加
え、一方、固定基準電源から、固定抵抗と最小点
調整用可変抵抗とを順次直列に接続して他端を接
地し、この固定抵抗と最小点調整用可変抵抗との
接続点と、前記オペレーシヨナルアンプの出力端
との間に、最大点調整用可変抵抗と調整すべき計
器とを直列にして接続してなるものである。[Means for Solving the Problems] The present invention was made to solve these conventional drawbacks, and uses an operational amplifier as a drive circuit for a movable iron-type instrument. Connect a resistor so that it is 1 or more, and apply a reference voltage to the non-inverting input side. On the other hand, from a fixed reference power supply, connect a fixed resistor and a variable resistor for minimum point adjustment in series, and ground the other end. The variable resistor for maximum point adjustment and the instrument to be adjusted are connected in series between the connection point between this fixed resistor and the variable resistor for minimum point adjustment and the output terminal of the operational amplifier. It is something.

［作用］最小点調整時には基準電圧を可変して最小点用
電圧を加える。この状態におけるオペレーシヨナ
ルアンプの出力電圧と、接続点の電圧が同じにな
るように、最小点用可変抵抗を調整する。つま
り、２点間が同一電圧となつて第２図に示すよう
に電流が零となり、計器の振れは最小となる。[Function] When adjusting the minimum point, the reference voltage is varied and the voltage for the minimum point is applied. Adjust the minimum point variable resistor so that the output voltage of the operational amplifier in this state is the same as the voltage at the connection point. In other words, the voltage between the two points becomes the same, the current becomes zero as shown in FIG. 2, and the swing of the meter becomes minimum.

つぎに、最大点調整時には基準電圧を可変して
最大点用電圧を加える。この状態において計器の
振れが第２図に示すように最大となるように可最
大点用変抵抗を調整する。このようにして、最初
は最小点調整、つぎに最大点調整の順序で行なう
ことにより、それぞれ独立調整される。 Next, when adjusting the maximum point, the reference voltage is varied and a voltage for the maximum point is applied. In this state, the variable resistance for the maximum possible point is adjusted so that the deflection of the instrument becomes maximum as shown in FIG. In this way, by first performing the minimum point adjustment and then the maximum point adjustment, each is independently adjusted.

［実施例］以下、本考案の一実施例を図面について説明す
る。[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

OPは、差動入力型のオペレーシヨナルアンプ
で、このオペレーシヨナルアンプOPの非反転入
力側（＋）には、抵抗Riを介して可変できる基
準電圧Eiが印加される。また、他方の入力端
（−）と出力端V₀との間にも抵抗R₂を接続し、こ
れらの抵抗R₁，R₂により利得が１以上になるよ
うに、つまり、利得が（１＋R₂／R₁）E₁ となるように設定されている。 OP is a differential input type operational amplifier, and a variable reference voltage Ei is applied to the non-inverting input side (+) of this operational amplifier OP via a resistor Ri. In addition, a resistor R ₂ is also connected between the other input terminal (-) and the output terminal V ₀ so that the gain becomes 1 or more by these resistors R ₁ and R ₂ , that is, the gain becomes (1+R ₂ /R ₁ )E ₁ .

一方、固定基準電源E₂から固定抵抗R₀と最小
調整用可変抵抗RV₁を直列に介して接地する。ま
た、オペレーシヨナルアンプOPの出力端V₀と前
記固定抵抗R₀と最小点調整用可変抵抗RV₁との
接続点VR間には、最大点調整用可変抵抗RV₂と
調整すべき計器Ｍと逆振れ防止用のダイオードＤ
を直列にして接続する。E₁はオペレーシヨナル
アンプOPの駆動電源である。 On the other hand, a fixed reference power source E ₂ is connected to ground through a fixed resistor R ₀ and a minimum adjustment variable resistor RV ₁ in series. Furthermore, between the output terminal V ₀ of the operational amplifier OP and the connection point VR between the fixed resistor R ₀ and the minimum point adjustment variable resistor RV ₁ , there is a maximum point adjustment variable resistor RV ₂ and a meter M to be adjusted. Diode D for preventing reverse vibration
Connect in series. _E1 is the driving power supply for the operational amplifier OP.

つぎに、本考案の動作説明をする。 Next, the operation of the present invention will be explained.

まず、最小点調整時には、基準電圧Eiを可変し
て第２図のように最小点用電圧Ei₁を加える。こ
の状態におけるオペレーシヨナルアンプOPの出
力電圧V₀と、接続点VRの電圧が同じになるよう
に、最小点用可変抵抗RV₁を調整する。つまり、
２点間が同一電圧となつて第２図に示すように電
流Ｉが零となり、計器Ｍの振れは最小となる。 First, when adjusting the minimum point, the reference voltage Ei is varied and a minimum point voltage Ei ₁ is applied as shown in FIG. The minimum point variable resistor RV ₁ is adjusted so that the output voltage V ₀ of the operational amplifier OP in this state is the same as the voltage at the connection point VR. In other words,
When the voltage between the two points becomes the same, the current I becomes zero as shown in FIG. 2, and the swing of the meter M becomes minimum.

つぎに、最大点調整時には基準電圧Eiを可変し
て最大点用電圧Ei₂を加える。この状態において
計器Ｍの振れが第２図に示すように最大となるよ
うに可最大点用変抵抗RV₂を調整する。このよう
にして、最初は最小点調整、つぎに最大点調整の
順序で行なうことにより、それぞれ独立調整され
る。なお、この回路において、最大点調整用可変
抵抗RV₂と、固定抵抗R₀および最小点調整用可
変抵抗RV₁との関係は RV₂≫R₀×RV₁／R₀＋RV₁ であることが望ましい。さもないと、最大点調整
時に、接続点VRの電圧が変動し、正しい調整が
できない場合がある。 Next, when adjusting the maximum point, the reference voltage Ei is varied and a maximum point voltage Ei ₂ is added. In this state, the variable resistance RV ₂ for the maximum possible point is adjusted so that the deflection of the meter M becomes maximum as shown in FIG. In this way, by performing the minimum point adjustment first and then the maximum point adjustment in this order, each is independently adjusted. In this circuit, the relationship between the variable resistance RV ₂ for maximum point adjustment, the fixed resistance R ₀ and the variable resistance RV ₁ for minimum point adjustment is RV ₂ ≫R ₀ ×RV ₁ /R ₀ +RV _1. desirable. Otherwise, when adjusting the maximum point, the voltage at the connection point VR may fluctuate and correct adjustment may not be possible.

［考案の効果］本考案は上述のような構成したので、計器の最
小点調整と最小点調整とがそれぞれ独立して行な
え極めて簡単で、また、回路自体も簡素化され、
かつ安価になり、さらに負電源や温度保証回路が
一切不要であるなどの効果を有するものである。[Effects of the invention] Since the present invention is constructed as described above, the minimum point adjustment of the meter and the minimum point adjustment can be performed independently, making it extremely simple, and the circuit itself is simplified.
It is also inexpensive, and has the advantage of not requiring any negative power supply or temperature guarantee circuit.

[Brief explanation of the drawing]

第１図は本考案による計器の駆動回路の１実施
例を示す電気回路図、第２図は動作特性図、第３
図は従来のトランジスタ駆動回路図である。 OP……オペレーシヨナルアンプ、R₁，R₂，
Ri，R₀……固定抵抗、Ei……可変できる基準電
圧、E₁，E₂……固定基準電圧、RV₁……最小点
調整用可変抵抗、RV₂……最大点調整用可変抵
抗、Ｍ……電流駆動型の可動鉄片式計器、Ｄ……
ダイオード。 Fig. 1 is an electric circuit diagram showing one embodiment of a meter drive circuit according to the present invention, Fig. 2 is an operating characteristic diagram, and Fig. 3
The figure is a diagram of a conventional transistor drive circuit. OP...Operational amplifier, R ₁ , R ₂ ,
Ri, R ₀ ...Fixed resistance, Ei...Variable reference voltage, _E1 , _E2 ...Fixed reference voltage, RV ₁ ...Variable resistance for minimum point adjustment, RV ₂ ...Variable resistance for maximum point adjustment, M... Current-driven movable iron piece meter, D...
diode.

Claims

[Claims for Utility Model Registration] (1) A scale adjustment reference power source is coupled to the non-inverting input side of an operational amplifier having a gain of 1 or more, and a variable resistor for maximum point adjustment and a meter to be adjusted are connected to the output side. are connected in series, the other end of this meter is connected to the series connection point of a fixed resistor and a variable resistor for minimum point adjustment, a fixed reference power source is connected to the other end of the fixed resistor, and a variable resistor for minimum point adjustment is connected to the other end of the fixed resistor. An instrument drive circuit consisting of a resistor with the other end grounded. (2) Scope of utility model registration claim where the relationship among the variable resistor RV ₂ for maximum point configuration, fixed resistor R ₀ and variable resistor RV ₁ for minimum point adjustment is RV ₂ ≫R ₀ ×RV ₁ /R ₀ +RV ₁ A drive circuit for the meter according to item 1.