JPS62180258A - Humidity detecting circuit - Google Patents
Humidity detecting circuitInfo
- Publication number
- JPS62180258A JPS62180258A JP61023556A JP2355686A JPS62180258A JP S62180258 A JPS62180258 A JP S62180258A JP 61023556 A JP61023556 A JP 61023556A JP 2355686 A JP2355686 A JP 2355686A JP S62180258 A JPS62180258 A JP S62180258A
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- resistance
- operational amplifier
- sensitive resistor
- humidity
- 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.)
- Granted
Links
- 238000001514 detection method Methods 0.000 claims abstract description 16
- 238000010411 cooking Methods 0.000 abstract description 12
- 230000007423 decrease Effects 0.000 abstract description 5
- 230000003321 amplification Effects 0.000 abstract description 3
- 238000003199 nucleic acid amplification method Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Electric Ovens (AREA)
Abstract
Description
【発明の詳細な説明】
く技術分野〉
本発明は、電子レンジ等の調理器において、その調理の
仕上りを湿度により検知するための湿度検知回路に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a humidity detection circuit for detecting the completion of cooking using humidity in a cooking device such as a microwave oven.
〈従来技術〉
従来の湿度検知回路は、例えば、第６図のごとく構成し
ている。すなわち、金属被膜を利用して、温度により抵
抗値が正の温度係数をもって直線変化する第一感温抵抗
Ｈと第二感温抵抗Ｎとを用い、一方の第一感温抵抗Ｈに
大電流定電流回路ＩＨにより自己加熱しながら出力電圧
ＶＨを取り出す０もう一方の第二感温抵抗Ｎは微小定電
流回路ＩＮにより周囲温度に比例した電圧ＶＮを取り出
す。<Prior Art> A conventional humidity detection circuit is configured as shown in FIG. 6, for example. That is, by using a metal film, a first temperature-sensitive resistor H and a second temperature-sensitive resistor N whose resistance value changes linearly with temperature with a positive temperature coefficient are used, and a large current is applied to one of the first temperature-sensitive resistors H. The other second temperature-sensitive resistor N takes out an output voltage VH while self-heating by a constant current circuit IH, and takes out a voltage VN proportional to the ambient temperature by a minute constant current circuit IN.
乾燥状態で両者の電圧差がＶＮ−ＶＨが零になるよう定
電流値を設定すると、差電圧は周囲温度にかかわらず零
になる。電子レンジの調理の進行により空気中に水蒸気
が含まれると、１５０℃〜２００℃に自己加熱した第一
感温抵抗Ｈは水蒸気により熱が吸収されて温度が低下し
、第一感温抵抗Ｈ側の電圧が低下する０第二感温抵抗Ｎ
側の出力電圧ＶＮは変化しないので、結果として、ＶＮ
−ＶＨが零でなくなる。この電圧を演算増幅器ＯＰ３に
よりＲｆ／Ｒ９倍増幅して湿度の有無を検出する。演算
増幅器ＯＰＩ、演算増幅器ＯＰ２は出力電圧ＶＮ 、
ＶＴ（を演算増幅器ＯＰ３に云えるための電圧フォロワ
ーである。If the constant current value is set so that the voltage difference between the two is zero (VN-VH) in a dry state, the differential voltage will be zero regardless of the ambient temperature. When water vapor is included in the air due to the progress of cooking in a microwave oven, the first temperature-sensitive resistor H, which has self-heated to 150°C to 200°C, absorbs heat from the water vapor and its temperature decreases, and the first temperature-sensitive resistor H The voltage on the side decreases when the second temperature-sensitive resistor N
Since the side output voltage VN does not change, as a result, VN
-VH is no longer zero. This voltage is amplified nine times by Rf/R by an operational amplifier OP3 to detect the presence or absence of humidity. Operational amplifier OPI and operational amplifier OP2 output voltage VN,
This is a voltage follower to tell the operational amplifier OP3.
第−感温抵抗ＨＪ第二感温抵抗Ｎの０℃における抵抗値
をそれぞれＲＨ，ＲＮ、温度係数をαＨ１αＮ、温度ｔ
Ｈ，ｔＮにおける抵抗値をｒＨ，ｒＮとすると次式が成
立する。The resistance values at 0°C of the first temperature-sensitive resistor HJ and second temperature-sensitive resistor N are RH and RN, the temperature coefficient is αH1αN, and the temperature t
If the resistance values at H and tN are rH and rN, the following equation holds true.
ｒＨ＝ＲＨ（１＋αＨ−ｔＨ） ・−−−−−■
ｒＮ＝ＲＮ（１＋αＮ・ｔＮ） ・・−■一方、
自己加熱による温度上昇（ｔＨ−ｉＮ）は、第一感温抵
抗Ｈの消費電力と直線関係にある。ｔＮは周囲温度に等
しいため、
ｒＨ・ＩＨ”＝ｈｍ（ＬＨ−ｔＮ）Ｓ −■ただし、
ｈｍ：熱伝達係数
Ｓ：第一感温抵抗Ｈの表面積
０式と０式より
となり、乾燥状態でｈｍが一定の時には、■式の前項は
定数となるから、自己加熱側の第一感温抵抗Ｈば０℃で
抵抗値が
ＲＨ
となり、温度係数αＨの感温抵抗と等価になる。rH=RH(1+αH-tH) ・------■
rN=RN(1+αN・tN)...-■On the other hand,
The temperature rise (tH-iN) due to self-heating has a linear relationship with the power consumption of the first temperature-sensitive resistor H. Since tN is equal to the ambient temperature, rH・IH”=hm(LH−tN)S −■ However,
hm: Heat transfer coefficient S: Surface area of first temperature sensing resistor H From equations 0 and 0, when hm is constant in a dry state, the previous term of equation (■) becomes a constant, so the first temperature sensing resistor on the self-heating side If the resistance H is 0°C, the resistance value becomes RH, which is equivalent to a temperature-sensitive resistance with a temperature coefficient αH.
ここで、第６図の演算増幅器ＯＦ＋、演算増幅器ＯＦ２
の出力電圧はそれぞれ
ＶＮ＝ｒＮ弓Ｎ＝ＲＮ・ＩＮ（Ｉ＋αＮ−ｔＮ） ・
・・・・＠となる。演算増幅器ＯＰ３の出力Ｖｏｕｔは
であるが、今αＨ＝αＮ１
になるようＩＮとＩＨを設定して常数設定すると、■式
のＶｏｕｔは乾燥状態下でｈｍは一定であるので常ＫＯ
になる。■式を書きなおすと次式になる。Here, the operational amplifier OF+ and the operational amplifier OF2 in FIG.
The output voltage of each is VN = rN bow N = RN・IN(I+αN−tN) ・
...becomes @. The output Vout of the operational amplifier OP3 is, but if we set IN and IH so that αH = αN1 and set a constant, Vout in equation (2) is always KO since hm is constant under dry conditions.
become. ■Rewriting the equation gives the following equation.
乾燥状態ではｈｍが一定であるが、調理が経過して調理
物から水蒸気が出始めると、ｈｍが増大するので、Ｖｏ
ｕｔが０から急激に増大し、湿度検知ができる。Ｖｏｕ
ｔの時間的変化の様子を第７図に示す。In a dry state, hm is constant, but as the cooking progresses and steam begins to come out from the food, hm increases, so Vo
ut increases rapidly from 0, and humidity can be detected. Vou
FIG. 7 shows how t changes over time.
しかし、第６図の従来湿度検知回路では、定電流源がＩ
ＨとＩＮの２個と、演算増幅器が演算増幅器ＯＦ＋、演
算増幅器ＯＰ２、演算増幅器ＯＰ３と、回路素子を多数
（３個）必要とする上、■式の条件を満たすため２個の
定電流源のＩＨとＩＮ相互を合わせこむのが非常に困難
であった。However, in the conventional humidity detection circuit shown in Fig. 6, the constant current source is
H and IN, operational amplifiers OF+, operational amplifier OP2, operational amplifier OP3, and a large number (3) of circuit elements are required.In addition, two constant current sources are required to satisfy the condition of formula (■). It was extremely difficult to match the IH and IN.
〈目 的〉
そこで、本発明は、２個の定電流源相互を合わせこまな
くても良い湿度検知回路の提供を目的としている。<Purpose> Therefore, an object of the present invention is to provide a humidity detection circuit that does not require matching two constant current sources.
〈実施例〉
本発明による電子レンジの調理の仕上りを湿度により検
知する湿度検知回路の原理を第１．２図により説明する
。<Embodiment> The principle of a humidity detection circuit for detecting the finish of cooking in a microwave oven according to the present invention based on humidity will be explained with reference to FIG. 1.2.
第１図で、定電流源１ｏにより第一感温抵抗Ｈ≦
を自己加熱する点は第一図と同じであるが、本発明では
、第二感温抵抗Ｎを第一感温抵抗Ｈの出力と演算増幅器
ＯＰの反転入力に挿入している点が異なっている。In Fig. 1, the point that the first temperature-sensitive resistor H≦ is self-heated by the constant current source 1o is the same as in Fig. 1, but in the present invention, the second temperature-sensitive resistor N is The difference is that it is inserted between the output and the inverting input of the operational amplifier OP.
すなわち、本発明は、湿度を検出するために自己加熱す
る第一感温抵抗Ｈと、周囲温度検出用の第二感温抵抗Ｎ
と、定電流源Ｉｏと、演算増幅器ＯＰと、該演算増幅器
ＯＰ用帰還抵抗Ｒｆとを具備し、前記第一感温抵抗Ｈを
定電流源１ｏにより自己加熱し、さらに第一感温抵抗Ｈ
の端子電圧を第二感温抵抗Ｎを通して演算増幅器ＯＰの
反転側入力端子に入力するよう構成し念ものである。こ
のため、本発明では、従来湿度検知回路と比べて部品点
数をきわめて少なくできる。That is, the present invention includes a first temperature-sensitive resistor H that self-heats to detect humidity, and a second temperature-sensitive resistor N for detecting ambient temperature.
, a constant current source Io, an operational amplifier OP, and a feedback resistor Rf for the operational amplifier OP, the first temperature sensitive resistor H is self-heated by the constant current source 1o, and the first temperature sensitive resistor H
It is assumed that the terminal voltage is inputted to the inverting input terminal of the operational amplifier OP through the second temperature-sensitive resistor N. Therefore, in the present invention, the number of components can be significantly reduced compared to conventional humidity detection circuits.
第１図でｒＨ＜＜ｒＮ とすると、自己加熱側の第一感
温抵抗Ｈの両端電圧ＶＨは■式と同様にとなる。演算増
幅器ＯＰの利得は、ｒ Ｈ＜＜ ｒ Ｎ としている
ため
Ｒｆ Ｒｆ
ｒＨ＋ｒＮ ｒＮ
であるから、αＨ＝αＮに選定すると、出力ＶＯｕｔは
Ｆ
と導出される。In FIG. 1, if rH<<rN, the voltage VH across the first temperature-sensitive resistor H on the self-heating side will be the same as in equation (2). Since the gain of the operational amplifier OP is Rf Rf rH+rN rN since r H<< r N , if αH=αN is selected, the output VOut is derived as F .
乾燥状態では、ｈｍ（熱伝達係数）ｉｉ′一定のため、
出力Ｖｏｕｔ ｔｒｉ負の一定値になる。調理が経過し
発生した水蒸気によりｈｍが増大すると、Ｖｏｕｔの絶
対値が小さくなり、第２図のような出力の時間経過を得
ることができる。In the dry state, since hm (heat transfer coefficient) ii' is constant,
The output Vout tri becomes a constant negative value. As hm increases due to steam generated as cooking progresses, the absolute value of Vout becomes smaller, making it possible to obtain the output over time as shown in FIG.
第３図は、本発明による実施例である。第１図では演算
増幅器ＯＰの電源に正負の両型源が必要とし念が、第３
図では正電源のみで済ませられるように簡略化している
。FIG. 3 is an embodiment according to the present invention. In Figure 1, both positive and negative type sources are required for the power supply of the operational amplifier OP.
The diagram is simplified so that only the positive power supply is required.
第３図で演算増幅器ＯＰＩ、トランジスタＱ、抵抗Ｒ５
および基準電源Ｖｒｅｆにより定電流回路を構成し、第
一感温抵抗Ｈに定電流１ ｏ＝Ｖ ｒ ｅ ｆ／ＲＳを
供給している。トランジスタＱは演算増幅器ＯＰＩの出
力電流増幅用である。第二感温抵抗Ｎは第１図々同様に
周囲温度検出用の感温抵抗である。演算増幅器ＯＰ２は
信号の増幅用である。第３図の出力電圧Ｖｏｕｔは、α
Ｈ＝αＮの時Ｖｏｕｔ＝
・・・０
と導出される。まず、調理の初期状態で、Ｖｏｕｔを一
定値になるよう、演算増幅器ＯＰ２の負端子に接続され
ている抵抗ＲＢを調節しておく０調理が進行して調理物
の水蒸気によりｈｍが増大すると、［相］式の１項目が
減少する。その結果Ｖｏｕｔが急激に増大し、第４図の
ような時間特性になる。In Figure 3, operational amplifier OPI, transistor Q, and resistor R5
A constant current circuit is configured by the reference power supply Vref and a constant current 1 o=V r e f /RS is supplied to the first temperature sensitive resistor H. Transistor Q is for amplifying the output current of operational amplifier OPI. The second temperature-sensitive resistor N is a temperature-sensitive resistor for detecting the ambient temperature as in FIG. Operational amplifier OP2 is for signal amplification. The output voltage Vout in FIG. 3 is α
When H=αN, Vout=...0 is derived. First, in the initial state of cooking, adjust the resistor RB connected to the negative terminal of the operational amplifier OP2 so that Vout remains at a constant value.As cooking progresses and hm increases due to the steam of the food, [Phase] One item in the equation decreases. As a result, Vout increases rapidly, resulting in a time characteristic as shown in FIG.
上記第１図の原理のものにおいてはαＨ＝αＮと選定し
なければならず、αＨ＝αＮと選定すると七は感温抵抗
の性能上困難である。According to the principle shown in FIG. 1, it is necessary to select αH=αN, and if αH=αN is selected, it is difficult in view of the performance of the temperature-sensitive resistor.
そこで本発明の湿度検知回路の他の実施例においては、
（ｔＨ＝αＮの関係を成立させる必要がなくても湿度の
検知が行なえるようにしたものである。Therefore, in another embodiment of the humidity detection circuit of the present invention,
(This allows humidity to be detected without the need to establish the relationship tH=αN.
本発明の湿度検知回路の他の実施例を第５図により説明
する。Another embodiment of the humidity detection circuit of the present invention will be described with reference to FIG.
上記第１図と異なる所は第一感温抵抗Ｈの両端電圧ｖＨ
ｔ−第二感温抵抗Ｎ及び直列に接続された抵抗Ｒｃを通
じて演算増幅器ＯＦの反転側入力端子に接続している所
にある。The difference from the above figure 1 is that the voltage across the first temperature-sensitive resistor H is vH.
t- is connected to the inverting side input terminal of the operational amplifier OF through the second temperature sensitive resistor N and the resistor Rc connected in series.
すなわち、湿度を検知する為に自己加熱する第一感温抵
抗Ｈ七周囲温度検出用の第二感温抵抗Ｎと、定電流源１
ｏと、演算増幅器ＯＰと該演算増幅器用帰還抵抗Ｒｆと
第二感温抵抗Ｎと直列に接続する抵抗Ｒｃとを具備し、
前記第一感温抵抗Ｈを定電流源１ｏにより自己加熱し、
さらに第一感温抵抗Ｈの端子電圧を第二感温抵抗Ｎ及び
第二感温抵抗Ｎに直列に接続された抵抗Ｒｃを通して演
算増幅器ＯＰの反転側入力端子に入力するよう構成した
ものである。That is, a first temperature-sensitive resistor H that heats itself to detect humidity, a second temperature-sensitive resistor N for detecting ambient temperature, and a constant current source 1.
o, an operational amplifier OP, a feedback resistor Rf for the operational amplifier, and a resistor Rc connected in series with the second temperature-sensitive resistor N,
The first temperature-sensitive resistor H is self-heated by a constant current source 1o,
Further, the terminal voltage of the first temperature-sensitive resistor H is inputted to the inverting side input terminal of the operational amplifier OP through the second temperature-sensitive resistor N and a resistor Rc connected in series with the second temperature-sensitive resistor N. .
この回路によりαＨとｒＮを等しくすることなく湿度検
知回路を構成することができる。With this circuit, a humidity detection circuit can be constructed without making αH and rN equal.
第５図による演算増幅器の利得は
Ｒｆ
Ｖｏｕｔ ： □ＶＨ−（ｒＮ＋
Ｒｃ ）
と導出される。The gain of the operational amplifier according to FIG. 5 is Rf Vout: □VH-(rN+
Rc) is derived.
となる様にＲｃを選定してやると 出力Ｖｏｕｔは 但しＣは定数と導出される。If we select Rc so that The output Vout is However, C is derived as a constant.
乾燥状態でばｈｍは一定の為、出力Ｖｏｕｔは一定値で
あり、調理が経過し発生した水蒸気により１１ｍが増大
するとＶｏｕｔの絶対値が小さくなり第２図のような出
力の時間経過を得ることができる。In a dry state, since hm is constant, the output Vout is a constant value, and as 11m increases due to the steam generated as cooking progresses, the absolute value of Vout decreases, and the output over time as shown in Figure 2 can be obtained. I can do it.
〈効 果〉
本発明の湿度検知回路は上記のような構成であるから、
第一感温抵抗、第二感温抵抗のそれぞれの湿度係数αＨ
２αＮを合わせることなく、直列に接続する抵抗を調整
するのみで電子レンジ等の調理の仕上りを湿度により検
知することができ、食品の自動加熱に構成効果が大きい
。<Effects> Since the humidity detection circuit of the present invention has the above configuration,
Humidity coefficient αH of the first temperature-sensitive resistor and the second temperature-sensitive resistor
The finish of cooking in a microwave oven or the like can be detected based on humidity by simply adjusting the resistor connected in series without adjusting 2αN, which has a great structural effect in automatic heating of food.
第１図は本発明による湿度検知回路を用いた電子レンジ
の仕上り検知用電子回路の原理図、第２図は本発明によ
る仕上り検知回路の出力電圧の時間特性の概略を表わす
線図、第３図は第１図の本発明湿度検知回路の実施例を
示す電子回路図、第４図は第３図の出力電圧の時間特性
の概略を表わ１！さ
す線図、第５図は本発明による湿度検知回路を用いた電
子レンジの仕上り検知用電子回路の他の原理図、第６図
は従来湿度検知回路を用いた電子レンジの仕上り検知用
電子回路図、第７図はその出力電圧の時間特性の概略を
表わす線図であるＯＨ：第一感温抵抗、■０：定電流源
、Ｎ：第二感温抵抗、ＯＰ：演算増幅器、Ｒｆ：帰還抵
抗、ＲＣ：抵抗
代理人 弁理士 杉 山 毅 至（他１名）Ｖｏｕｔ
第２ 図
Ｖｏｕｔ
第４ 図FIG. 1 is a principle diagram of an electronic circuit for detecting finished product in a microwave oven using a humidity detecting circuit according to the present invention, FIG. This figure is an electronic circuit diagram showing an embodiment of the humidity detection circuit of the present invention shown in FIG. 1, and FIG. 4 shows an outline of the time characteristics of the output voltage shown in FIG. 3. Fig. 5 is another principle diagram of an electronic circuit for detecting the finish of a microwave oven using the humidity detection circuit according to the present invention, and Fig. 6 is an electronic circuit for detecting the finish of a microwave oven using a conventional humidity detection circuit. 7 is a diagram schematically showing the time characteristics of the output voltage. OH: first temperature-sensitive resistor, ■0: constant current source, N: second temperature-sensitive resistor, OP: operational amplifier, Rf: Return resistance, RC: Resistance agent Patent attorney Takeshi Sugiyama (and 1 other person) Vout Figure 2 Vout Figure 4
Claims (1)
囲温度検出用の第二感温抵抗と、定電流源と、演算増幅
器と、該演算増幅器用帰還抵抗と第二感温抵抗に直列に
挿入する抵抗とを具備し、前記第一感温抵抗を定電流源
により自己加熱し、さらに第一感温抵抗の端子電圧を第
二感温抵抗及び第二感温抵抗に直列に接続された抵抗を
通して演算増幅器の反転側入力端子に入力するよう構成
したことを特徴とする湿度検知回路。A first temperature-sensitive resistor that heats itself to detect humidity, a second temperature-sensitive resistor for detecting ambient temperature, a constant current source, an operational amplifier, a feedback resistor for the operational amplifier, and a second temperature-sensitive resistor. and a resistor inserted in series, the first temperature sensitive resistor is self-heated by a constant current source, and the terminal voltage of the first temperature sensitive resistor is connected in series to the second temperature sensitive resistor and the second temperature sensitive resistor. A humidity detection circuit characterized in that the humidity detection circuit is configured to input to an inverting side input terminal of an operational amplifier through a resistor.
Priority Applications (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61023556A JPS62180258A (en) | 1986-02-04 | 1986-02-04 | Humidity detecting circuit |
| DE3751125T DE3751125T2 (en) | 1986-02-04 | 1987-01-30 | Moisture measuring circuit. |
| EP87101319A EP0232817B1 (en) | 1986-02-04 | 1987-01-30 | Humidity detecting circuit |
| NZ219136A NZ219136A (en) | 1986-02-04 | 1987-02-02 | Humidity detector circuit |
| CA000528880A CA1287986C (en) | 1986-02-04 | 1987-02-03 | Humidity detecting circuit |
| KR878700873A KR890004076B1 (en) | 1986-02-04 | 1987-02-04 | Humidity detecting circuit |
| AU68287/87A AU574947B2 (en) | 1986-02-04 | 1987-02-04 | Humidity detection |
| US07/010,794 US4768378A (en) | 1986-02-04 | 1987-02-04 | Humidity detecting circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61023556A JPS62180258A (en) | 1986-02-04 | 1986-02-04 | Humidity detecting circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62180258A true JPS62180258A (en) | 1987-08-07 |
| JPH0531939B2 JPH0531939B2 (en) | 1993-05-13 |
Family
ID=12113777
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61023556A Granted JPS62180258A (en) | 1986-02-04 | 1986-02-04 | Humidity detecting circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62180258A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102809589A (en) * | 2012-07-25 | 2012-12-05 | 华东师范大学 | Air humidity measurement method with low power consumption |
| CN103558251A (en) * | 2013-10-30 | 2014-02-05 | 成都市宏山科技有限公司 | High-precision relative humidity detection device |
-
1986
- 1986-02-04 JP JP61023556A patent/JPS62180258A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102809589A (en) * | 2012-07-25 | 2012-12-05 | 华东师范大学 | Air humidity measurement method with low power consumption |
| CN103558251A (en) * | 2013-10-30 | 2014-02-05 | 成都市宏山科技有限公司 | High-precision relative humidity detection device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0531939B2 (en) | 1993-05-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |