JPH0514935U - Watt meter - Google Patents
Watt meterInfo
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- JPH0514935U JPH0514935U JP1242491U JP1242491U JPH0514935U JP H0514935 U JPH0514935 U JP H0514935U JP 1242491 U JP1242491 U JP 1242491U JP 1242491 U JP1242491 U JP 1242491U JP H0514935 U JPH0514935 U JP H0514935U
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Abstract
(57)【要約】
【目的】 電流測定器Ａと電圧測定器Ｖの挿入損失の影
響を軽減できる電力計を提供すること。
【構成】 電流端子と共通端子の間に接続されたシャン
ト抵抗と、一端が電流端子に接続され、他端がスイッチ
の第１接点(b) に接続された第１抵抗(r1)と、一端が共
通端子に接続され、他端がスイッチの第２接点(a)に接
続された第２抵抗(r2)と、一端が電圧端子に接続され他
端がスイッチの固定接点(C) に接続された第３抵抗(r3)
と、シャント抵抗の両端の電圧を導入しこれに流れる電
流値を測定する電流側アンプと、前記電流側アンプで測
定した電流値が設定電流値より小さい場合、前記スイッ
チを第１接点に駆動し、設定電流値より大きい場合、前
記スイッチを第２接点に駆動する制御回路と、を備える
ようにしたもの。
(57) [Abstract] [Purpose] To provide a power meter that can reduce the influence of insertion loss of a current measuring device A and a voltage measuring device V. [Structure] A shunt resistor connected between the current terminal and the common terminal, a first resistor (r1) having one end connected to the current terminal and the other end connected to the first contact (b) of the switch, and one end Is connected to the common terminal, the other end is connected to the second contact (a) of the switch, and the second resistor (r2) is connected to the voltage terminal and the other end is connected to the fixed contact (C) of the switch. 3rd resistance (r3)
And a current side amplifier that introduces the voltage across the shunt resistor and measures the current value flowing through it, and drives the switch to the first contact when the current value measured by the current side amplifier is smaller than the set current value. A control circuit for driving the switch to the second contact when the current value is larger than the set current value.
Description
【０００１】[0001]
本考案は、電力計の入力回路に関するものである。 The present invention relates to an input circuit of a power meter.
【０００２】[0002]
電力計は、負荷に加えられる電圧と電流を測定し、この測定値を乗算して電力 値を得ている。ここで、電流端子の一端と電圧端子の一端が１つの端子を共用す る所謂共通端子方式の電力計において、電圧測定回路と電流測定回路の接続の仕 方は、図２に示すように２通りある。 図２(a) は、電流端子PAと共通端子（±）の間に電流測定器Ａを接続し、電圧 端子PVと共通端子（±）の間に電圧測定器Ｖを接続したものである。 図２(b) は、電流端子PAと共通端子（±）の間に電流測定器Ａを接続し、電圧 端子PVと電流端子PAの間に電圧測定器Ｖを接続したものである。 The wattmeter measures the voltage and current applied to the load and multiplies the measurements to get the power value. Here, in a so-called common terminal type wattmeter in which one end of the current terminal and one end of the voltage terminal share one terminal, the connection method of the voltage measurement circuit and the current measurement circuit is as shown in FIG. There is a street. In FIG. 2A, the current measuring device A is connected between the current terminal PA and the common terminal (±), and the voltage measuring device V is connected between the voltage terminal PV and the common terminal (±). In FIG. 2B, the current measuring device A is connected between the current terminal PA and the common terminal (±), and the voltage measuring device V is connected between the voltage terminal PV and the current terminal PA.
【０００３】 図２の電流測定器Ａは、通常、内蔵するシャント抵抗（抵抗値rsが既知の低抵 抗）を回路へ直列に挿入し、このシャント抵抗rsに被測定電流ｉL が流れた結果 発生する電圧ｅ＝rs・ｉL を測定することで、ｉL ＝ｅ／rsにより電流測定を行 っている。従って、図２において、電流測定器Ａの内部抵抗は低抵抗である。 一方、電圧測定器Ｖは、高抵抗の入力インピーダンスのアンプで被測定電圧を 受けるので、その内部抵抗は高抵抗と見ることができる。In the current measuring device A of FIG. 2, a built-in shunt resistance (a low resistance whose resistance value rs is known) is usually inserted in series into the circuit, and the measured current i L flows through this shunt resistance rs. By measuring the resulting voltage e = rs · i L , the current is measured by i L = e / rs. Therefore, in FIG. 2, the internal resistance of the current measuring device A is low. On the other hand, since the voltage measuring device V receives the voltage to be measured by the amplifier having a high resistance input impedance, its internal resistance can be regarded as a high resistance.
【０００４】[0004]
ところで、図２(a) ，(b) の接続の仕方は、それぞれ次の問題がある。 (1) 図２(a) の接続法は、電圧測定器Ｖの消費電力分が負荷で消費する電力に加 算して測定され誤差となる。つまり、電圧測定器Ｖの内部抵抗をＲVM、負荷抵抗 をRLとした場合、RL << ＲVM の関係が成立しないほど、負荷抵抗RLの値が大き いと、電圧測定器Ｖの消費電力分が無視できなくなり、正確な負荷電力を測定で きなくなる。 (2) 図２(b) の接続法は、電流測定器Ａの消費電力分が負荷で消費する電力に加 算されて測定され誤差となる。つまり電流測定器Ａのシャント抵抗をrsとした場 合、rs << RL の関係が成立しないほど、負荷抵抗RLの値が小さいと、電流測定 器Ａの消費電力分が無視できなくなり正確な負荷電力を測定できなくなる。By the way, the connection methods of FIGS. 2 (a) and 2 (b) have the following problems, respectively. (1) In the connection method shown in Fig. 2 (a), the power consumption of the voltage measuring device V is added to the power consumed by the load and measured, resulting in an error. That is, when the internal resistance of the voltage measuring device V is R VM and the load resistance is RL, if the value of the load resistance RL is so large that the relationship of RL << R VM is not satisfied, the power consumption of the voltage measuring device V is reduced. Cannot be ignored, and accurate load power cannot be measured. (2) In the connection method of Fig. 2 (b), the power consumption of the current measuring instrument A is added to the power consumed by the load and measured, resulting in an error. In other words, when the shunt resistance of the current measuring instrument A is rs, if the value of the load resistance RL is so small that the relationship of rs << RL does not hold, the power consumption of the current measuring instrument A cannot be ignored and the accurate load is not obtained. The power cannot be measured.
【０００５】 本考案の目的は、電流測定器Ａと電圧測定器Ｖの挿入損失の影響を軽減できる 電力計を提供することである。An object of the present invention is to provide a power meter that can reduce the influence of insertion loss of the current measuring device A and the voltage measuring device V.
【０００６】[0006]
以上の課題を解決するため本考案は、 電圧端子(PV)と電流端子(PA)のそれぞれの一端が共通であり、電圧端子と共通 端子（±）間に負荷を接続し、電圧端子と電流端子間に電源を接続して、負荷に 加えられる電力を測定する装置において、 電流端子と共通端子の間に接続されたシャント抵抗と、 一端が電流端子に接続され、他端がスイッチの第１接点(b) に接続された第１ 抵抗(r1)と、 一端が共通端子に接続され、他端がスイッチの第２接点(a) に接続された第２ 抵抗(r2)と、 一端が電圧端子に接続され、他端がスイッチの固定接点(C) に接続された第３ 抵抗(r3)と、 シャント抵抗の両端の電圧を導入し、これに流れる電流値を測定する電流側ア ンプと、 第３抵抗の両端の電圧値を測定する電圧側アンプと、 この電圧側アンプと電流側アンプの出力の乗算を行う乗算器と、 前記電流側アンプで測定した電流値が設定電流値より小さい場合、前記スイッ チを第１接点に駆動し、設定電流値より大きい場合、前記スイッチを第２接点に 駆動する制御回路と、 を備えるようにしたものである。 In order to solve the above problems, the present invention has one end of each of the voltage terminal (PV) and the current terminal (PA) common, and connects a load between the voltage terminal and the common terminal (±), In a device for measuring power applied to a load by connecting a power supply between terminals, a shunt resistor connected between a current terminal and a common terminal, one end of which is connected to the current terminal, and the other end of which is the first switch The first resistor (r1) connected to the contact (b), the second resistor (r2) connected to the common terminal at one end and the second contact (a) of the switch, and one end to the voltage The third resistor (r3), which is connected to the terminal and the other end is connected to the fixed contact (C) of the switch, and the current-side amplifier that introduces the voltage across the shunt resistor and measures the current flowing through it. , A voltage side amplifier that measures the voltage value across the third resistor, and a voltage side amplifier and a current side amplifier A multiplier for multiplying the force, and if the current value measured by the current-side amplifier is smaller than the set current value, drive the switch to the first contact, and if it is larger than the set current value, set the switch to the second contact. And a control circuit for driving.
【０００７】[0007]
電流側アンプは、シャント抵抗の両端の電圧を導入し、これに流れる電流値を 測定する。また、制御回路は、電流側アンプで測定した電流値が設定電流値より 小さい場合、スイッチを第１接点に駆動し、設定電流値より大きい場合、スイッ チを第２接点に駆動する。つまり、 (1) 負荷が低抵抗の場合、図２(a) の接続となるようにスイッチを切り替え、 (2) 負荷が高抵抗の場合、図２(b) の接続となるようにスイッチを切り替えてい る。 The current-side amplifier introduces the voltage across the shunt resistor and measures the current flowing through it. Further, the control circuit drives the switch to the first contact when the current value measured by the current-side amplifier is smaller than the set current value, and drives the switch to the second contact when the current value is larger than the set current value. In other words, (1) When the load has low resistance, switch the switch so that the connection is as shown in Fig. 2 (a), and (2) When the load is high resistance, the switch is as shown in Fig. 2 (b). It is switching.
【０００８】 負荷抵抗RLが低抵抗の場合、RL << ＲVM の関係（ＲVM：電圧測定器Ｖの内部 抵抗）が成立するので、図２(a) の接続によれば、電圧測定器Ｖの消費電力は、 負荷電力と比較して無視できるほどの大きさになり、正確に負荷電力を測定でき る。 また負荷抵抗RLが高抵抗の場合、rs << RL の関係（rs：電流測定器Ａの内部 抵抗）が成立するので、図２(b) の接続によれば、電流測定器Ａの消費電力分は 、負荷電力と比較して無視できるほどの大きさとなり、正確に負荷電力を測定で きる。When the load resistance RL is low, the relationship of RL << R VM (R VM : internal resistance of the voltage measuring device V) is established. Therefore, according to the connection of FIG. The power consumption of V is negligible compared to the load power, and the load power can be measured accurately. When the load resistance RL is high, the relationship of rs << RL (rs: internal resistance of the current measuring device A) is established. Therefore, according to the connection of Fig. 2 (b), the power consumption of the current measuring device A is The minutes are negligible compared to the load power, and the load power can be measured accurately.
【０００９】[0009]
図１は本考案に係る電力計の構成例である。図１の電力計は、電圧端子PVと電 流端子PAの他方の端子が１つの端子（±）を共用する所謂共通端子方式の電力計 である。そして電圧端子PVと共通端子（±）間には負荷２が接続され、電圧端子 PVと電流端子PA間には電源１が接続される。図１の電力計は、この電源１から負 荷２に加えられる電力を測定する装置である。電力計１は、電流側アンプ３と、 電圧側アンプ４と、乗算器５と、制御回路６と、シャント抵抗rsと、抵抗r1〜r3 と、スイッチS1とで構成される。 FIG. 1 is a structural example of a power meter according to the present invention. The power meter in FIG. 1 is a so-called common terminal type power meter in which the other terminal of the voltage terminal PV and the current terminal PA shares one terminal (±). The load 2 is connected between the voltage terminal PV and the common terminal (±), and the power supply 1 is connected between the voltage terminal PV and the current terminal PA. The power meter of FIG. 1 is a device for measuring the power applied to the load 2 from the power supply 1. The power meter 1 includes a current side amplifier 3, a voltage side amplifier 4, a multiplier 5, a control circuit 6, a shunt resistor rs, resistors r1 to r3, and a switch S1.
【００１０】 シャント抵抗rsは、電流端子PAと共通端子（±）の間に接続され、この両端の 電圧は、電流側アンプ３に導かれる。このシャント抵抗rsと電流側アンプ３とで 図２に示す電流測定器Ａに相当する機能を構成する。電流側アンプ３は、シャン ト抵抗rsの両端の電圧ｅを導入し、ｉL ＝ｅ／rsの演算を行って、シャント抵抗 に流れる電流値ｉL を測定するものである。The shunt resistor rs is connected between the current terminal PA and the common terminal (±), and the voltage across the both ends is guided to the current side amplifier 3. The shunt resistance rs and the current-side amplifier 3 constitute a function corresponding to the current measuring device A shown in FIG. The current-side amplifier 3 introduces the voltage e across the shunt resistor rs, calculates i L = e / rs, and measures the current value i L flowing through the shunt resistor.
【００１１】 抵抗r1〜r3は、抵抗分圧器を形成するもので、通常、高抵抗で構成される。抵 抗r1は、その一端が電流端子PAに接続されたシャント抵抗rsの一端に接続され、 他端がスイッチS1の接点ｂに接続される。抵抗r2は、その一端が共通端子（±） に接続されたシャント抵抗rsの他端に接続され、他端がスイッチS1の接点ａに接 続される。抵抗r3はその一端が電圧端子PVに接続され、他端がスイッチS1の固定 接点Ｃに接続される。電圧側アンプ４は、抵抗r3の両端の電圧を高入力インピー ダンスの増幅器で受け、この電圧値を測定するものである。この電圧側アンプ４ と抵抗r1〜r3とで図２に示す電圧測定器Ｖに相当する機能を形成する。 乗算器５は、電圧側アンプ４で測定した負荷２の電圧と、電流側アンプ３で測 定した負荷２に流れる電流との乗算を行い電力値を算出するものである。 制御回路６は、電流側アンプ３で測定した電流値が設定電流値より小さい場合 、スイッチS1を接点ｂに駆動し、設定電流値より大きい場合、スイッチS1を接点 ａに駆動するものである。The resistors r1 to r3 form a resistance voltage divider, and are usually composed of high resistances. The resistor r1 has one end connected to one end of the shunt resistor rs connected to the current terminal PA, and the other end connected to the contact b of the switch S1. The resistor r2 has one end connected to the other end of the shunt resistor rs connected to the common terminal (±), and the other end connected to the contact a of the switch S1. The resistor r3 has one end connected to the voltage terminal PV and the other end connected to the fixed contact C of the switch S1. The voltage side amplifier 4 receives the voltage across the resistor r3 with an amplifier having a high input impedance and measures the voltage value. The voltage side amplifier 4 and the resistors r1 to r3 form a function corresponding to the voltage measuring device V shown in FIG. The multiplier 5 multiplies the voltage of the load 2 measured by the voltage side amplifier 4 by the current flowing through the load 2 measured by the current side amplifier 3 to calculate a power value. The control circuit 6 drives the switch S1 to the contact b when the current value measured by the current side amplifier 3 is smaller than the set current value, and drives the switch S1 to the contact a when it is larger than the set current value.
【００１２】 このような電力計は次のように動作する。 電流側アンプ３は、シャント抵抗rsの両端の電圧を導入し、これに流れる電流 値を測定する。また、制御回路６は、電流側アンプ３で測定した電流値が設定電 流値（この値は、制御回路６に内蔵している）より小さい場合、スイッチS1を接 点ｂに駆動し、設定電流値より大きい場合、スイッチを接点ａに駆動する。つま り、 (a) 負荷２が低抵抗の場合、図２(a) の接続となるようにスイッチS1を切り替 え、 (b) 負荷２が高抵抗の場合、図２(b) の接続となるようにスイッチS1を切り替 えている。Such a power meter operates as follows. The current-side amplifier 3 introduces the voltage across the shunt resistor rs and measures the current value flowing through it. When the current value measured by the current-side amplifier 3 is smaller than the set current value (this value is built in the control circuit 6), the control circuit 6 drives the switch S1 to the contact point b to set it. When it is larger than the current value, the switch is driven to the contact a. In other words, if load (a) has a low resistance, switch S1 is switched to the connection shown in Fig. 2 (a), and (b) if load 2 has a high resistance, the connection shown in Fig. 2 (b) is used. Switch S1 is switched so that
【００１３】 このように電流アンプ３で測定したシャント抵抗rsに流れる電流値によりスイッ チS1を切り替えることで、電流測定器Ａ（図１ではシャント抵抗rsと電流側アン プ３）と、電圧測定器Ｖ（図１では抵抗r3と電圧側アンプ４）の挿入損失の影響 を軽減できる。その理由を説明する。 上記(a) における負荷２の抵抗RLが低抵抗の場合、スイッチS1は接点ａ側に接 続され、この場合、RL << ＲVM の関係（ＲVM＝r2＋r3：電圧測定器Ｖの内部抵 抗）が成立する。つまり、負荷２の消費電力は、VL2 ／RLであり、電圧測定器Ｖ の消費電力は、VL2 ／ＲVMである（VLは負荷２の両端に発生する電圧）。したが って、RL << ＲVM であるから、電圧測定器Ｖ（抵抗r2とr3と電圧側アンプ）の 消費電力は、負荷電力と比較して無視できるほどの大きさになり、正確に負荷電 力を測定できる。By switching the switch S1 according to the value of the current flowing through the shunt resistance rs measured by the current amplifier 3 as described above, the current measuring device A (in FIG. 1, the shunt resistance rs and the current side amplifier 3) and the voltage measurement are measured. The effect of the insertion loss of the device V (the resistor r3 and the voltage side amplifier 4 in FIG. 1) can be reduced. The reason will be explained. When the resistance RL of the load 2 in (a) above is low, the switch S1 is connected to the contact a side, and in this case, the relationship of RL << R VM (R VM = r2 + r3: internal resistance of the voltage measuring device V). Anti) is established. That is, the power consumption of the load 2 is VL 2 / RL, and the power consumption of the voltage measuring device V 2 is VL 2 / R VM (VL is the voltage generated across the load 2). Therefore, since RL << R VM , the power consumption of the voltage measuring device V (the resistors r2 and r3 and the amplifier on the voltage side) is negligible compared to the load power, and is accurate. The load power can be measured.
【００１４】 また、上記(b) における負荷２の抵抗RLが高抵抗の場合、スイッチS1は接点ｂ 側に接続され、この場合、rs << RL の関係（rs：電流測定器Ａの内部抵抗＝シ ャント抵抗）が成立する。つまり、負荷２に流れる電流をｉL とすると、負荷２ の消費電力は、ｉL 2 ・RL であり、電流測定器Ａの消費電力は、ｉL 2 ・rs である。従って、rs << RL であるから、電流測定器Ａ（シャント抵抗rsと電流 側アンプ３）の消費電力分は、負荷電力と比較して無視できるほどの大きさとな り、正確に負荷電力を測定できる。When the resistance RL of the load 2 in the above (b) is high resistance, the switch S1 is connected to the contact b side, and in this case, the relationship of rs << RL (rs: internal resistance of the current measuring device A). = Shunt resistance) is established. That is, assuming that the current flowing through the load 2 is i L , the power consumption of the load 2 is i L 2 · RL, and the power consumption of the current measuring device A is i L 2 · rs. Therefore, since rs << RL, the power consumption of the current measuring instrument A (shunt resistance rs and current side amplifier 3) is negligible compared with the load power, and the load power can be accurately measured. Can be measured.
【００１５】 なお、上述では、電流側アンプ３の測定電流値に基づき制御回路６で判断して スイッチS1を切り替えると説明した。図１の電力計は、シャント抵抗rsが１個の 単一測定レンジの電力計であるが、複数のシャント抵抗を持ち電流測定レンジを 切り替えることができる電力計では、この電流測定レンジの情報を制御回路６で 受信して、この情報に基づいてスイッチS1の切り替え制御をするようにしてもよ い。 即ち、大電流を測定する電流測定レンジが選択された場合、この情報を制御回 路６で受け、スイッチS1を接点ａとなるように（図２(a) の接続となるように） 切り替える。つまり、この場合、負荷２は低抵抗が予想されるからである。 また、逆に小電流を測定する電流測定レンジが選択された場合、制御回路６は 、スイッチS1を接点ｂに切り替える。この場合、負荷２は高抵抗が予想されるか らである。In the above description, the control circuit 6 makes a decision based on the measured current value of the current-side amplifier 3 to switch the switch S1. The wattmeter shown in Fig. 1 is a wattage meter with a single shunt resistance rs and a single measurement range. The control circuit 6 may receive and control the switching of the switch S1 based on this information. That is, when the current measuring range for measuring a large current is selected, this information is received by the control circuit 6, and the switch S1 is switched to the contact a (the connection of FIG. 2 (a)). That is, in this case, the load 2 is expected to have low resistance. Conversely, when the current measurement range for measuring a small current is selected, the control circuit 6 switches the switch S1 to the contact b. In this case, the load 2 is expected to have high resistance.
【００１６】[0016]
以上説明したように本考案によれば、制御回路６により、 (1) 負荷が低抵抗の場合、図２(a) の接続となるようにスイッチを切り替え、 (2) 負荷が高抵抗の場合、図２(b) の接続となるようにスイッチを切り替えてい るので、電流測定器Ａと電圧測定器Ｖの挿入損失の影響を軽減できる。 As described above, according to the present invention, by the control circuit 6, (1) when the load has a low resistance, the switch is switched so that the connection is as shown in FIG. 2 (a), and (2) when the load has a high resistance. Since the switches are switched so that the connection shown in FIG.
【図１】本考案に係る電力計の構成例を示す図FIG. 1 is a diagram showing a configuration example of a power meter according to the present invention.
【図２】電圧測定回路と電流測定回路の接続の仕方を示
す図FIG. 2 is a diagram showing how to connect a voltage measuring circuit and a current measuring circuit.
１ 電源 ２ 負荷 ３ 電流側アンプ ４ 電圧側アンプ ５ 乗算器 ６ 制御回路 rs シャント抵抗 r1〜r3 抵抗 S1 スイッチ 1 power supply 2 load 3 current side amplifier 4 voltage side amplifier 5 multiplier 6 control circuit rs shunt resistance r1 to r3 resistance S1 switch
Claims (1)
一端が共通であり、電圧端子と共通端子（±）間に負荷
を接続し、電圧端子と電流端子間に電源を接続して、負
荷に加えられる電力を測定する装置において、 電流端子と共通端子の間に接続されたシャント抵抗と、 一端が電流端子に接続され、他端がスイッチの第１接点
(b) に接続された第１抵抗(r1)と、 一端が共通端子に接続され、他端がスイッチの第２接点
(a) に接続された第２抵抗(r2)と、 一端が電圧端子に接続され、他端がスイッチの固定接点
(C) に接続された第３抵抗(r3)と、 シャント抵抗の両端の電圧を導入し、これに流れる電流
値を測定する電流側アンプと、 第３抵抗の両端の電圧値を測定する電圧側アンプと、 この電圧側アンプと電流側アンプの出力の乗算を行う乗
算器と、 前記電流側アンプで測定した電流値が設定電流値より小
さい場合、前記スイッチを第１接点に駆動し、設定電流
値より大きい場合、前記スイッチを第２接点に駆動する
制御回路と、 を備えたことを特徴とする電力計。1. A voltage terminal (PV) and a current terminal (PA) have one common end, a load is connected between the voltage terminal and the common terminal (±), and a power supply is connected between the voltage terminal and the current terminal. Then, in the device for measuring the electric power applied to the load, the shunt resistor connected between the current terminal and the common terminal, one end of which is connected to the current terminal, and the other end of which is the first contact of the switch.
The first resistor (r1) connected to (b) and one end connected to the common terminal and the other end the second contact of the switch
The second resistor (r2) connected to (a) and one end is connected to the voltage terminal and the other end is the fixed contact of the switch.
The third resistor (r3) connected to (C), the current side amplifier that introduces the voltage across the shunt resistor and measures the current flowing through it, and the voltage that measures the voltage across the third resistor. A side amplifier, a multiplier that multiplies the outputs of the voltage side amplifier and the current side amplifier, and if the current value measured by the current side amplifier is smaller than the set current value, the switch is driven to the first contact to set And a control circuit that drives the switch to the second contact when the current value is larger than the current value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1242491U JPH0514935U (en) | 1991-03-07 | 1991-03-07 | Watt meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1242491U JPH0514935U (en) | 1991-03-07 | 1991-03-07 | Watt meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0514935U true JPH0514935U (en) | 1993-02-26 |
Family
ID=11804898
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1242491U Withdrawn JPH0514935U (en) | 1991-03-07 | 1991-03-07 | Watt meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0514935U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS49146035U (en) * | 1973-04-19 | 1974-12-17 | ||
| JPS49146034U (en) * | 1973-04-19 | 1974-12-17 | ||
| JPS6111521U (en) * | 1984-06-26 | 1986-01-23 | ザ・パツク株式会社 | confectionery packaging paper box |
-
1991
- 1991-03-07 JP JP1242491U patent/JPH0514935U/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS49146035U (en) * | 1973-04-19 | 1974-12-17 | ||
| JPS49146034U (en) * | 1973-04-19 | 1974-12-17 | ||
| JPS5422503Y2 (en) * | 1973-04-19 | 1979-08-06 | ||
| JPS5422502Y2 (en) * | 1973-04-19 | 1979-08-06 | ||
| JPS6111521U (en) * | 1984-06-26 | 1986-01-23 | ザ・パツク株式会社 | confectionery packaging paper box |
| JPH0245143Y2 (en) * | 1984-06-26 | 1990-11-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19950615 |