JP2002098715A - Power consumption measuring table tap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To directly display power consumption of electric machinery and apparatus connected to a table tap 1 on a display installed on the table tap, to thereby facilitate power saving in a general home, to notify a customer concretely of the characteristic of a power saving commodity at a store, and to install an alarm means for being used in the range of a rated capacity. SOLUTION: Plural plug sockets 3, switches 4 for switching connection of each plug socket with an external power source to the ON or OFF state, a current transformer 9 for measuring a current flowing out from the plug sockets 3, a measuring part 5 for operating a momentary power, a CO2 conversion value, or an integrated electric charge from the output of the current transformer 9, and a display part 6 for displaying the power consumption are stored and arranged in a case from which an electric wire connected to the external power source is drawn out. A means for issuing an alarm of a sound or light, when a measurement value exceeds a set value, is also provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A power strip is a cable in which a plug is attached at a tip thereof is drawn out of a case in which a plurality of outlets are arranged and accommodated, and is used to connect a plurality of electric devices to one outlet.

Some power strips have a switch for turning on / off power supply to each outlet. As for this switch, there are a switch for turning on and off all outlets with one switch, and a switch for turning on and off individually by providing a switch for each outlet. 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 power supply to unnecessary electrical equipment and to save power.

[0005]

In the above-mentioned conventional power strip, the outlets can be disconnected from the power source all at once or individually by a switch.

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

In order to save power, it is necessary not only to disconnect electrical equipment that is not used, but also to select electrical equipment that does not need to be energized in consideration of standby power consumption that is consumed even when not in use. There is.

In this case, it is necessary to determine the values of the power consumption and the standby power consumption by measuring the voltage and current by using a tester, or to read the instruction manual or the like. is there. However, it is almost impossible technically to perform measurement using a tester in ordinary households, and it is not realistic to save the power by reading the instruction manual.

In recent years, many electric appliances characterized by power saving have been created. When explaining the actual effect to customers at a store, it is necessary to read and store an instruction manual and the like. However, it is difficult to do this for a wide variety of products without error, and even customers who have been explained are not convinced by simple numbers.

[0010] Therefore, the present invention makes it possible to easily save power in ordinary households by directly displaying the power consumption of electric equipment connected to the power strip on a display provided on the power strip. It is also an object of the present invention to provide a measured value of the power consumption of an electric product to be sold to a customer as it is, so that the characteristics of the power-saving product can be clearly communicated.

[0011]

According to a first aspect of the present invention, there is provided a power consumption measuring table tap including a plurality of outlets provided in a case where an electric wire connected to a commercial power supply is drawn out;
A switch that turns on and off the connection between each outlet and the external power supply, a measuring unit that measures the amount of power consumed by electrical equipment connected to the outlet, and a display that displays power consumption are stored and arranged. And

According to a second aspect of the present invention, in the power consumption measuring table tap according to the first aspect, the measuring unit measures a current flowing out of the outlet, and the current transformer measures the current. A rectifier circuit for converting the converted AC current to a DC voltage, a comparator for comparing the output of the low-pass filter for averaging the pulse width modulation signal to a DC voltage with the output of the rectifier circuit, and an output of the comparator. A controller connected to the end and changing the pulse width duty ratio of the modulation signal until the output from the comparator is inverted, and quantifying the pulse width duty ratio at that time to calculate a power amount. It is characterized by being.

According to a third aspect of the present invention, in the power consumption measuring table tap according to the second aspect, the rectifier circuit includes a combination of an operational amplifier and a rectifier diode. It is characterized in that an expanding linearity suppressing circuit is provided.

According to a fourth aspect of the present invention, in the power consumption measuring table tap according to the second or third aspect, the controller is configured to control an electric power amount and an electric charge and a power amount obtained by multiplying the electric power amount by the unit price. Means for calculating a CO ₂ conversion value, and the power amount, the electricity rate, and the CO ₂ conversion value are sequentially switched and displayed in a predetermined order on the display unit and at set time intervals. It is characterized by.

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 switch is provided for 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, a current transformer is provided for each outlet, and the measuring unit is connected to the outlet. The power consumption is calculated for each outlet, and the display unit individually displays the power consumption of each outlet.

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

[0018]

1 and 2 show an external configuration 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 outlets 3, 3,..., Switches 4, 4,..., A measuring section 5, and a storage section of the display 6 are formed by resin molding. The outlets 3, 3, ... are arranged and accommodated 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 on, and is arranged and stored along each outlet. The measuring section 5 is assembled on a printed circuit board, and is arranged and fixed in a storage space provided in a case. The display 6 has an LCD display or the like arranged and fixed at a position where the case is easy to see, and has, for example, display segments as shown in FIG. Reference numeral 7 denotes an electric wire for external connection, for example, a 2-core vinyl electric wire is used. Reference numeral 8 denotes a plug fixed to the end of the electric wire 7 for inserting and connecting to an outlet provided on a wall in the room.

FIG. 4 shows an electric circuit of the table tap 1 shown in FIGS. 1 and 2. Each outlet 3,
3, ... are switches with pilot lights 4,4, ...
Are connected in parallel to two electric wires 7 having plugs 8 connected to the ends.

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

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

The AC current I measured by the current transformer 9 is converted to an AC voltage by the resistor R1. A rectifier circuit 12 converts the AC voltage into a DC voltage. A comparator 13 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 to the low-pass filter 14 while changing the pulse width duty ratio so as to gradually increase from 0%, and multiplies the amount of power and the amount of power by the unit price of charge based on the change in the output of the comparator 13. electricity charge was, and has a calculation of the electric energy of CO ₂ converted value, the count function of the cumulative energization time.

The specific configuration of the arithmetic circuit 10 will be described together with its operation. The AC current I measured by the current transformer 9 is divided by the resistors R1 and R2, and the AC current flowing through the negative resistor R2 is changed by the feedback resistor R3 connected to the operational amplifier OP.
, And at the same time, half-wave rectified by diodes D1 and D2. After the half-wave rectified voltage has its pulsating component removed by the capacitor C1, 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 so as to gradually increase from 0%, where the resistor R5 and the capacitor C2 are connected. A DC voltage V3 proportional to the pulse width duty ratio is generated via the DC / DC converter, and the DC voltage V3 is input to the other input terminal of the comparator 13.

The comparator 13 to which the above-mentioned DC constant pressures V1 and V3 have been respectively inputted becomes high level and outputs V4 when V3 ≧ V1, and when this output V4 is inputted 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 a proportional constant K. That is, W = T _ON / (T _ON + T _OFF ) × K T _ON : high-level time of V 2, T _OFF : low-level time of V 2 The above operation is repeated every λ at a fixed time interval, and the number of times of sampling ( When the elapsed time is T, the electric energy Wh is calculated by the following equation (1), and the calculated electric energy Wh is multiplied by a unit price {for example, 25 yen / kwh (fixed)} to calculate an electric charge. You.

[0025]

(Equation 1)

The converted CO ₂ value is obtained by dividing the measured power by 1
The amount of carbon dioxide released into the atmosphere at the thermal power plant to generate time is calculated by multiplying the electric energy Wh by a predetermined coefficient.

In the arithmetic circuit 10 as described above, only a controller 15 for performing pulse width modulation and power amount calculation as complicated digital conversion means is constituted by a one-chip microcomputer.
Otherwise, the current transformer 9 and the simple analog rectifier circuit 12 for converting the AC current measured by the current transformer 9 into DC may be combined. Cost and cost can be reduced.

The electric energy, the electricity rate and the CO ₂ conversion value calculated by the arithmetic circuit 10 are stored in the controller 1.
5, for example, as shown in FIG. 6, the integrated electricity rate, the instantaneous power, and the CO ₂
The LCD display 6 in the order of the converted values and at intervals of 3 seconds.
At the same time as the corresponding numerical value is displayed cyclically on the numerical value display section 6A, and the unit symbols are displayed in the unit symbol display section 6C in the order of "yen", "kw", and "kg-C" corresponding to each display item. Is displayed, and when the electric equipment plugged into the outlet 3 consumes power, the operation display section 6B of the LCD display 6 is configured to blink the dots at one-second intervals.

The rectifier circuit 12 of the arithmetic circuit 10 shown in FIG.
As shown in FIG. 7, the measurement range can be expanded by adding a linearity suppressing circuit. This rectifier circuit 12A
A second feedback resistor R4 is connected in parallel with the feedback resistor R3 in the rectifier circuit 12 comprising the operational amplifier OP, diodes D1 and D2 for half-wave rectification, a low-pass filter R3, and a 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 rectifier circuit 12A to which the above-described linearity suppressing circuit is added will be described. When the input value of the AC current I flowing from the current transformer 9 is equal to or lower than the Zener diode ZD voltage in the range from the point 0 to the point a in FIG. 8, no current flows through the second feedback resistor R4, and Since the voltage is amplified only by the resistor R3, the amplification degree A
_{V 0} is A _V0 = R3 / R2. On the other hand, when the input value is equal to or higher than the point a in FIG. 8 and equal to or higher than the voltage of the Zener diode ZD, a current also flows through the second resistor R4. Therefore, the amplification A _V1 becomes A _V1 = R3 × R4 / R2. (R3 + R4), and the amplification decreases by the amount of the second feedback resistor R4.
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 accordingly, so that it is possible to measure even a minute power such as a standby power in a home electric appliance. The linearity correction accompanying the addition of the linearity suppression circuit can be solved only by adding a linearizer operation function in the controller 15.

The table tap 1 can be individually switched between a power supply state and a cutoff state by the switches 4, 4,... While the plugs of the electric devices are inserted into the outlets 3, 3,. .

Therefore, the power consumption and the like of each electric device can be easily checked by simply operating the switch, and the power consumption and the like of an arbitrary combination can be easily checked. Therefore, it is possible to easily devise for power saving in ordinary households. Also, in a home appliance store, the electric appliances to be compared can be easily connected to an outlet, and the power consumption and the like of each electric appliance can be easily compared only by operating the switch.

Further, as shown in FIG. 9, one current transformer 9 may be provided for each outlet, and the power consumption and the like may be measured for each outlet. In this case, a separate switch 10a is used to switch between the measurement and display of all outlets and the measurement and display of each outlet individually. The display on the display 6 when the measurement and display are performed individually is, for example, a cyclic display of the measurement value with the outlet number.

Although the above description has been made with respect to a power strip provided with a switch for each outlet, the present invention employs a single switch 4 for all outlets as shown in FIG.
The present invention is also applicable to a table tap of a type that simultaneously supplies and shuts off power.

In this case, since the individual measurement cannot be performed by operating the switch, only the electrical equipment to be measured is connected to the outlet, or all the electrical equipment to be used is connected to the outlet, and only the measured electrical equipment is connected. Is disconnected from the outlet, and the power consumption and standby power consumption of the target electric device are obtained from the change in the measured value.

As shown in FIG. 9, an alarm (indicator lamp, 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 blinking a lamp or sounding a buzzer to ensure safety.

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

[0038]

The power consumption measuring table tap according to the first aspect of the present invention can directly read the power consumption and the like of the electric equipment connected to a plurality of outlets, so that the use plan of the electric equipment for power saving in ordinary households is provided. Can be easily set up.

In the power consumption measuring table tap according to claim 2 of the present invention, the measuring unit is constituted by a controller which can use a microcomputer in addition to a current transformer, a rectifier circuit, a comparator and a low-pass filter. Since it can be configured, it is possible to achieve downsizing and cost reduction that can be easily incorporated in the power strip.

In the power consumption measuring table tap according to claim 3 of the present invention, a linearity suppressing circuit for expanding the measurement range is added to the rectifier circuit, so that the measurement range is expanded and, for example, such as standby power in home electric appliances. It is possible to measure from a small power to a normal power consumption.

Since the power consumption measuring table tap according to the fourth aspect of the present invention has a function of calculating and displaying a CO ₂ converted value of the power consumption or an integrated electricity rate in addition to the power consumption, the electric equipment is provided. It is possible to understand the environmental impact and economics of using the device, and it is possible to use electric equipment more accurately.

In the power consumption measuring table tap according to claim 5 of the present invention, since a switch is provided for each outlet, the power supply is cut off and turned on immediately after checking the measured power consumption and the like. Thus, the operation for power saving can be easily performed.

The power consumption measurement table tap according to claim 6 of the present invention calculates and displays power consumption and the like for each outlet, so that measurement can be performed with all electrical devices connected to the outlet, and power consumption can be reduced. Operation can be performed more easily.

The power tap for measuring power consumption according to claim 7 of the present invention emits an alarm by sound or light when the power consumption of the entire table tap exceeds a set value, so that the use state in which security standards are secured is maintained. be able to.

[Brief description of the 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 view showing an example of a display pattern of the display device shown in FIG. 1;

FIG. 4 is an electric circuit diagram of the power consumption measurement table tap of FIG. 1;

FIG. 5 is an electric circuit diagram of a measurement unit in FIG. 1;

FIG. 6 is a view showing a specific display example of the display of the display device of FIG. 1;

FIG. 7 is a diagram showing another embodiment of the rectifier of the measuring unit in FIG. 5;

FIG. 8 is a characteristic diagram of the rectifier in FIG. 7;

FIG. 9 is an electric circuit diagram showing an embodiment of a power consumption measurement table tap in which current transformers are 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]

 DESCRIPTION OF SYMBOLS 1 Power consumption measurement table tap 2 Case 3 Outlet 4 Switch 5 Display (LCD display part) 9 Current transformer 12 Rectifier circuit 13 Comparator 14 Low filter 15 Controller OP Operational amplifier

Claims (7)

[Claims] 1. A case where an electric wire connected to a commercial power supply is drawn out, a plurality of outlets, a switch for turning on / off a connection between each outlet and the commercial power supply, and electric power consumed by an electric device connected to the outlet. A power consumption measurement table tap characterized by containing and arranging a measurement unit for measuring the amount and a display for displaying power consumption. 2. A current transformer for measuring a current flowing out of an outlet, a rectifier circuit for converting an AC current measured by the current transformer to a DC voltage, and a pulse width modulation signal converted to a DC voltage. A comparator for comparing the output of the low-pass filter to be averaged with the output of the rectifier circuit, and a pulse width duty of the modulation signal connected to an output terminal of the comparator until the output from the comparator is inverted. The power consumption measurement table tap according to claim 1, further comprising: a controller that changes the ratio and quantifies a pulse width duty ratio at that time to calculate a power amount. 3. The rectifier circuit according to claim 2, wherein the rectifier circuit comprises a combination of an operational amplifier and a rectifier diode, and the rectifier circuit is provided with a linearity suppressing circuit for expanding a measurement range. Power consumption measurement table tap. 4. The controller has means for calculating an electric energy, an electric charge obtained by multiplying the electric energy, and a CO ₂ converted value of the electric energy, wherein the electric energy, the electric charge, and the CO ₂ converted value are calculated. 4. The power consumption measurement table tap according to claim 2, wherein the power consumption measurement table tap is configured to be sequentially switched and displayed on the display in a predetermined order and at a set time interval. 5. 5. The power consumption measuring tap according to claim 1, wherein a switch is provided for each outlet. 6. A current transformer is provided for each outlet, the measuring unit calculates power consumption for each outlet, and the display unit displays the power consumption of each outlet individually. 6. The power consumption measurement table tap according to any one of items 5 to 5. 7. When the power consumption supplied from the entire power strip exceeds a set value determined according to the rated power,
The power consumption measurement table tap according to any one of claims 1 to 6, further comprising means for issuing an alarm by sound or light.