JP3369155B2 - Power consumption measurement table tap - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a table tap having a power consumption display function.

[0002]

2. Description of the Related Art A table tap is a case in which a plurality of outlets are arranged and housed, and an electric wire having a plug attached to the tip thereof is pulled out from the case. The table tap is used to connect a plurality of electric devices to one outlet.

Some of the table taps have a switch for turning on / off the power supply to each outlet. As for this switch, one switch turns on / off all outlets, and another switch is provided for each outlet to turn on / off individually. This switch generally has a built-in pilot lamp that lights up when turned on.

The main purpose of using this switch is to cut off the power supply to unnecessary electric equipment to save power.

[0005]

In the above conventional table tap, the outlets can be disconnected from the power source all at the same time or individually.

The one that is disconnected at the same time is suitable for connecting an electric device to be used at the same time, such as a personal computer and peripheral devices such as a display thereof, and the one that is disconnected separately is a home television, an electric pot, a fan, etc. It is suitable for connecting electrical equipment that is not always used at the same time.

Power saving is performed not only by disconnecting unused electric equipment but also by selecting electric equipment which does not need to be energized in consideration of standby power consumption which is consumed even when not in use. There is.

In this case, the values of the power consumption and the standby power consumption need to be calculated by measuring the voltage and current using a tester or reading the instruction manual or the like. is there. However, it is technically almost impossible to perform measurement using a tester in a general home, and it is not realistic to save power by spending time and effort to read the instruction manual.

[0009] Recently, many electric appliances featuring power saving have been born, but when explaining the actual effect to the customer at the store, it is necessary to read and memorize the instruction manual and the like. However, it is difficult to do this for a wide variety of products without errors, and the customers who receive the explanation are not satisfied with the simple numbers.

In view of the above, the present invention makes it possible to easily save power in a general household by directly displaying the power consumption of an electric device connected to the table tap on a display provided on the table tap. In this case, the purpose is to show the measured value of the power consumption of the electric product to be sold to the customer as it is so that the characteristics of the power saving product can be clearly communicated.

[0011]

A power consumption measuring table tap according to claim 1 of the present invention includes a plurality of outlets in a case where an electric wire connected to a commercial power source is drawn out.
Power consumption measurement with a switch that turns on and off the connection between each outlet and an external power source, a measurement unit that measures the amount of power consumed by electrical equipment connected to the outlet, and a display unit that displays the power consumption It ’s a table tap,
The measuring unit measures the current flowing out of the outlet.
A current transformer and the AC current measured by this current transformer
Rectifier circuit to convert the pulse width modulation signal to DC voltage
The output of the low pass filter for averaging is equal to the output of the rectifier circuit.
A comparator to be compared, and the comparator connected to the output terminal of the comparator
Pulse of the above modulation signal until the output from the comparator is inverted
The pulse when changing the width duty ratio
With a controller that digitizes the width duty ratio and calculates the electric energy
Characterized in that it comprises a.

According to a second aspect of the present invention, in the power consumption measuring table tap according to the first aspect, the rectifying circuit is composed of a combination of an operational amplifier and a rectifying diode, and the measuring range is provided in the rectifying circuit. It is characterized in that a magnifying linearity suppressing circuit is additionally provided.

The invention according to claim 3 of the present invention is
In the power consumption measurement table tap described in 1 or 2 , the controller has a means for calculating a CO ₂ conversion value of the electric charge and the electric power by multiplying the electric power by the unit price of the electric power. It is characterized in that the electricity charge and the CO ₂ conversion value are sequentially switched and displayed on the display device in a predetermined order and at set time intervals.

The invention according to claim 4 of the present invention is characterized in that, in the power consumption measuring table tap according to any one of claims 1 to 3 , a switch is provided for each outlet.

According to a fifth aspect of the present invention, in the power consumption measuring table tap according to any one of the first to fourth aspects, a current transformer is provided for each outlet, and the measuring unit is an outlet. It is characterized in that the power consumption is calculated for each, and the display unit individually displays the power consumption of each outlet.

According to a sixth aspect of the present invention, in the power consumption measuring table tap according to any one of the first to fifth aspects, the power consumption supplied from the entire table tap is determined according to the rated power. And a means for issuing an alarm by sound or light when the set value is exceeded.

[0017]

1 and 2 show the external structure of a power consumption measuring table tap 1 according to an embodiment of the present invention. In the figure, reference numeral 2 denotes a case, and the receptacles for the outlets 3, 3, ..., Switches 4, 4, ..., Measuring unit 5, and indicator 6 are formed by resin molding. The outlets 3, 3, ... Are arranged and housed with their longitudinal directions aligned with the longitudinal direction of the case 2. Switches 4, 4, ...
It has a built-in pilot lamp that lights up when it is turned on, and it is arranged and stored along each outlet. The measuring unit 5 is assembled on a printed circuit board and arranged and fixed in a storage space provided in a case. The display 6 is an LCD display or the like arranged and fixed at a position where the case can be easily seen, and has a display segment as shown in FIG. 3, for example. Reference numeral 7 is an electric wire for external connection, for example, a two-core vinyl electric wire is used. Reference numeral 8 denotes a plug fixed to the tip of the electric wire 7 for inserting and connecting to an outlet or the like provided on the wall in the room.

FIG. 4 shows the electric circuit of the table tap 1 shown in FIGS. 1 and 2. Each outlet 3,
3, ... are switches with pilot lamps 4, 4, ...
Is connected in parallel to two electric wires 7 having a plug 8 connected to the end thereof.

The measuring section 5 comprises a current transformer 9 for detecting a current flowing to the outlet, an arithmetic circuit 10 and a power circuit 11 for the arithmetic circuit.

The arithmetic circuit 10 is constructed, for example, as shown in FIG.

The alternating current I measured by the current transformer 9 is converted into an alternating voltage by the resistor R1. A rectifier circuit 12 converts this AC voltage into a DC voltage. Reference numeral 13 denotes a comparator, which receives the output of the rectifier circuit 12 and the output of the low-pass filter 14 and outputs a high level or a low level. Reference numeral 15 denotes a controller, which outputs the pulse width duty ratio to the low-pass filter 14 while changing the pulse width duty ratio from 0% to be gradually increased. From the change in the output of the comparator 13, the electric energy and the electric energy are multiplied by the unit price. It also has the functions of calculating the electricity charge and the CO ₂ conversion value of the amount of power, and counting the cumulative energization time.

A specific configuration of the arithmetic circuit 10 will be described together with its operation. The alternating current I measured by the current transformer 9 is shunted by the resistors R1 and R2, and the alternating current flowing through the negative resistor R2 is the feedback resistor R3 connected to the operational amplifier OP.
At the same time, the voltage is amplified by the diode, and at the same time, it is half-wave rectified by the diodes D1 and D2. After the pulsating current component is removed by the capacitor C1 from the half-wave rectified voltage, the DC voltage V1 is input to the negative input terminal of the comparator 13. -
On the other hand, the pulse width modulation signal V2 output from the controller 15 is input to the low-pass filter 14 while its pulse width duty ratio is changed from 0% to gradually increase, and the resistor R5 and the capacitor C2 are connected to the pulse width modulation signal V2. A DC voltage V3 proportional to the pulse width duty ratio is generated via the DC voltage V3, and this DC voltage V3 is input to the other input terminal of the comparator 13.

The comparator 13 to which the DC constant pressures V1 and V3 are respectively input becomes a high level and outputs V4 when V3 ≧ V1, and when this output V4 is input to the controller 15, The power value W is calculated by multiplying the value of the pulse width duty ratio of the modulation signal V2 by the proportional constant K. That is, W = T _ON / (T _ON + T _OFF ) × K T _ON : High level time of V2, T _OFF : Low level time of V2 The above operation is repeated at regular time intervals for each λ, and the number of sampling times ( The electric energy Wh is calculated by the following equation (1), and the electric power is calculated by multiplying the calculated electric energy Wh by a unit price (for example, 25 yen / kwh (fixed)). It

[0024]

[Equation 1]

Further, the CO ₂ conversion value is obtained by measuring the measured electric power by 1
It is the amount of carbon dioxide released to the atmosphere at the thermal power plant in order to generate time, and is calculated by multiplying the electric energy Wh by a predetermined coefficient.

In the arithmetic circuit 10 as described above, only the controller 15 for performing pulse width modulation and power amount calculation as a complicated digital converting means is configured by a one-chip microcomputer,
Otherwise, the current transformer 9 and the simple analog rectifier circuit 12 for converting the alternating current measured by the current transformer 9 into the direct current may be combined, so that the circuit configuration of the entire electric energy indicator is simplified and small. And cost reduction can be achieved.

The electric energy, the electricity charge, and the CO ₂ conversion value calculated by the arithmetic circuit 10 are the same as those of the controller 1 described above.
In the order and time interval preset to 5, for example, as shown in FIG. 6, accumulated electricity charge, instantaneous electric power, and CO ₂
The LCD display 6 in the order of converted values and at intervals of 3 seconds.
At the same time that the corresponding numerical value is cyclically displayed on the numerical value display portion 6A, the unit symbol display portion 6C displays the unit symbols in the order of “yen”, “kw” and “kg-C” corresponding to each display item. Is displayed, and when the electric device plugged into the outlet 3 consumes power, the operation display portion 6B of the LCD display 6 is configured so that dots are displayed blinking at intervals of 1 second.

Rectifier circuit 12 of the arithmetic circuit 10 shown in FIG.
Can add a linearity suppressing circuit as shown in FIG. 7 to expand the measurement range. This rectifier circuit 12A
A second feedback resistor R4 is connected in parallel with the feedback resistor R3 in the rectifier circuit 12 which is a combination of the operational amplifier OP, the half-wave rectification diodes D1 and D2, the low-pass filter R3, and the capacitor C1. A Zener diode ZD for determining a feedback branch voltage and a freewheeling prevention diode D3 are connected in series with the second feedback resistor R4.

The operation of the rectifying circuit 12A to which the linearity suppressing circuit as described above is added will be described. When the input value of the alternating current I flowing from the current transformer 9 is equal to or lower than the Zener diode ZD voltage in the range from the 0 point to the a point in FIG. 8, no current flows in the second feedback resistor R4 and the feedback is performed. Since the voltage is amplified only by the resistor R3, its amplification degree A
_V0 is A _V0 = R3 / R2. On the other hand, if the input value is point a or more in Fig. 8, the Zener diode Z
When the voltage exceeds the D voltage, a current also flows in the second resistor R4, so that the amplification degree A _V1 becomes A _V1 = R3 × R4 / R2 (R3 + R4), and the amplification degree is equal to the second feedback resistor R4. Decreases.
As a result, the range of the input value up to the point b is expanded to the point c, and the measurement range is expanded to that extent, and a very small amount of power such as standby power in home electric appliances can be measured. The correction of the linearity due to the addition of the linearity suppressing circuit can be solved only by adding a linearizer calculation function in the controller 15.

The table tap 1 can be individually switched between the power supply state and the cut-off state by the switches 4, 4, ... With the plugs of the electric devices inserted in the respective outlets 3, 3 ,. .

Therefore, it is possible to easily check the individual power consumption of each electric device and the power consumption of an arbitrary combination by only operating the switch. Therefore, it is possible to easily make a device for power saving in a general household. In addition, even at a store of household electric appliances, it is possible to easily compare the power consumption of each electric product and the like only by connecting the electric product to be compared to an outlet and operating a switch.

Further, as shown in FIG. 9, it is also possible to provide one current transformer 9 for each outlet and measure the power consumption and the like for each outlet. In this case, the changeover switch 10a provided separately switches between measurement and display of the total of all outlets and measurement and display of each outlet individually. The display on the display 6 in the case of individually measuring and displaying is, for example, a cyclic display of the measured value together with the outlet number.

Although the above description has been given for the table tap having a switch for each outlet, the present invention, as shown in FIG.
It is also applicable to a table tap of a type that simultaneously supplies and cuts power.

In this case, since individual measurements cannot be made by operating the switches, only the electrical equipment to be measured should be connected to the outlet, or all the electrical equipment to be used should be connected to the outlet and only the measured electrical equipment should be connected. Remove the plug from the outlet and obtain the power consumption and standby power consumption of the target electrical equipment from the change in the measured value.

As shown in FIG. 9, an alarm device (indicator light, buzzer, etc.) 16 is provided in the case 2 of FIG. 1, and the measuring unit 5 monitors the maximum power consumption of the entire table tap. When the value exceeds the rated power, for example, 1450 W, the user can be notified by flashing a lamp or ringing a buzzer to ensure safety.

The measuring section 5 measures only the electric current by the current transformer 9 to measure the electric energy and the like. As shown in FIG. 10, the voltage transformer 17 is used to measure the supply voltage. By doing so, it is possible to improve the accuracy.

[0037]

The power consumption measuring table tap according to claim 1 of the present invention can directly read the power consumption and the like of the electric equipment connected to the plurality of outlets. Can be set up easily , and the measuring unit can be configured by a controller that can use a microcomputer in addition to the current transformer, the rectifier circuit, the comparator, and the low-pass filter. Achieving downsizing and cost reduction that can be easily incorporated.

In the power consumption measuring table tap according to claim 2 of the present invention, since the linearity suppressing circuit for expanding the measuring range is attached to the rectifying circuit, the measuring range can be expanded to, for example, standby power consumption in home electric appliances. It is possible to measure from very low power to normal power consumption.

The power consumption measuring table tap according to claim 3 of the present invention has a function of calculating and displaying the CO ₂ conversion value of the power consumption or the integrated electricity charge in addition to the power consumption. It is possible to understand the impact on the environment and the economic efficiency of the use of, and it is possible to use electrical equipment more accurately.

In the power consumption measuring table tap according to claim 4 of the present invention, since the switch is provided for each outlet, the measured power consumption and the like are immediately checked to immediately turn off / on the electric device. It can be determined and the operation for power saving can be easily performed.

Since the power consumption measuring table tap according to claim 5 of the present invention calculates and displays the power consumption and the like for each outlet, the measurement can be performed with all electrical equipment connected to the outlet, thus saving power. The operation for can be performed more easily.

The power consumption measuring table tap according to claim 6 of the present invention issues an alarm by sound or light when the power consumption of the entire table tap exceeds the set value, so that it keeps the use condition in which the safety standard is secured. be able to.

[Brief description of drawings]

FIG. 1 is a plan view showing an external configuration of an embodiment of a power consumption measurement table tap according to the present invention.

FIG. 2 is a side view showing an external configuration of an embodiment of a power consumption measurement table tap according to the present invention.

FIG. 3 is a diagram showing an example of a display pattern of the display unit of FIG.

FIG. 4 is an electric circuit diagram of the power consumption measurement table tap shown in FIG.

5 is an electric circuit diagram of the measuring unit shown in FIG.

FIG. 6 is a diagram showing a specific display example of display on the display unit of FIG. 1.

FIG. 7 is a diagram showing another embodiment of the rectifier of the measurement unit of FIG.

FIG. 8 is a characteristic diagram of the rectifier of FIG.

FIG. 9 is an electric circuit diagram showing an embodiment of a power consumption measurement table tap in which a current transformer is arranged for each outlet.

FIG. 10 is an electric circuit diagram showing an embodiment of a power consumption measurement table tap in which a switch is common to all outlets.

[Explanation of symbols]

1 Power consumption measurement table tap 2 cases 3 outlets 4 switches 5 Display (LCD display) 9 Current transformer 12 Rectifier circuit 13 Comparator 14 Low castle filter 15 Controller OP operational amplifier

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-4-315964 (JP, A) JP-A-11-8032 (JP, A) JP-A-10-282161 (JP, A) Registered utility model 3067768 ( JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01R 11/00-11/66 G01R 21/00-22/00 130

Claims (6)

(57) [Claims] 1. A case in which an electric wire connected to a commercial power source is drawn out, a plurality of outlets, a switch for turning on / off the connection between each outlet and the commercial power source, and electric power consumed by an electric device connected to the outlet. A consumption unit that stores and arranges a measuring unit that measures the amount and an indicator that displays power consumption
A power measuring table tap, wherein the measuring unit is a
A current transformer that measures the current flowing out of the cent and this current
Rectifier circuit that converts the alternating current measured by the instrument into a direct current voltage
And low-pass filtering that averages the pulse-width modulated signal into a DC voltage.
A comparator for comparing the output of the rectifier with the output of the rectifier circuit,
The output from this comparator is connected to the output of this comparator.
Change the pulse width duty ratio of the above modulation signal until it is inverted.
The pulse width duty ratio at that time.
It is equipped with a controller that digitizes and calculates the electric energy.
Characteristic power consumption measurement table tap. Wherein the rectifier circuit is a combination of the operational amplifier and the rectifying diode of claim 1, linearity suppression circuit to expand the measurement range to the rectifier circuit, characterized in that it is attached Power consumption measurement table tap. Wherein said controller comprises means for calculating the amount of power and CO ₂ conversion value of the electricity charge and the amount of power multiplied by this unit price, they power amount and the electricity rate and CO ₂ conversion value The power consumption measurement table tap according to claim 1 or 2 , which is configured to be sequentially switched and displayed on the display device in a predetermined order and at a set time interval. 4. A switch power measuring strip as set forth in any one of claims 1 to 3, characterized in that it is arranged in each outlet. 5. A current transformer is provided for each outlet, a measuring unit calculates power consumption for each outlet, and a display unit individually displays the power consumption of each outlet. ~ The power consumption measurement table tap described in any one of 4 . 6. When power is supplied from the entire strip exceeds the set value defined according to the rated power, claim 1-5, characterized in that it comprises means for issuing an alarm by sound or light The power consumption measurement table tap described in any one of 1.