JPH06303706A - Power distribution apparatus - Google Patents

Abstract

PURPOSE:To use an electric apparatus without paying attention to exceeding a rated available current. CONSTITUTION:Three ports 4, 5, 6 for a power supply connected with an electric apparatus are provided in plug socket states on a front surface of a body case. The port 4 is used for monitoring. One feeder 14 is connected to one terminals of the ports 4, 5, 6, and the other feeder 15 is connected to the other terminals of the ports 4, 5, 6. In this case, relay switches 17, 18 are inserted between the one terminal of the ports 5, 6 and the feeder 14. When a detected value of a current detector 20 for detecting an available current value of the port 4 exceeds a threshold value to be set by an up/down key 7, a controller 19 turns OFF switches 17, 18 to cut OFF power supplies of the ports 5, 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power distribution device having a plurality of power supply ports to which electric equipment is connected and distributing power to each of the power supply ports.

[0002]

2. Description of the Related Art In recent years, microwave ovens that can easily warm foods have become widespread. For example, even in a relatively small office such as a company, a microwave oven is installed in a dining room, a water heater, or the like. There are more and more places to do. However, since the microwave oven consumes a large amount of power (for example, the rated current is about 12 A), it is a power supply line having a relatively small power capacity (for example, the rated working current of 15 A), such as a word processor and other office equipment such as a personal computer. When a microwave oven is used at the same time as the electric device, the breaker is activated by exceeding the rated current, and the data in the word processor or the personal computer may be erased.

[0003]

As described above, in order to prevent the breaker from operating in excess of the rated operating current in a power supply line having a comparatively small power supply capacity, other electric power is required. It is necessary to pay close attention when using the microwave oven, such as using the microwave oven after switching off the equipment, or it becomes necessary to change the power capacity.

The present invention has been made in view of the above circumstances. An object of the present invention is not to worry that the rated operating current will be exceeded even in a power supply line having a relatively small power supply capacity. In order to provide a power distribution device that can be used.

[0005]

DISCLOSURE OF THE INVENTION A power distribution device of the present invention comprises a plurality of power supply ports to which electric equipment is connected, and distributes power to each of the power supply ports to supply the power. Current detecting means for detecting a used current value at a predetermined power supply port among the plurality of power supply ports, and another power supply when the used current value detected by the current detection means exceeds a threshold value. The present invention is characterized in that it comprises a current limiting means for cutting off the power supply to the supply port.

In this case, it is more effective to provide selection designating means for selectively designating the power supply port whose power supply is cut off by the current limiting means.

Further, threshold value setting means for setting the threshold value arbitrarily may be provided.

[0008]

According to the above means, by connecting the electric equipment to the plurality of power supply ports respectively, the electric power is supplied to each electric equipment to be used. When the current used by the electric device connected to the port is detected by the current detection means and the value of the used current exceeds a threshold value, the current limiting means shuts off the power supply to other power supply ports. Become.

Therefore, for example, an electric device that consumes a large amount of power temporarily is connected to a predetermined power supply port, and an electric device that does not cause a problem even if the power supply is temporarily cut off is supplied to another power supply. If it is used by connecting it to the port, it is possible to prevent the rated operating current from being exceeded without causing any serious trouble in the use of the electric device.

In this case, if the selection designating means for selectively designating the power supply port whose power supply is cut off by the current limiting means is provided, the user can temporarily supply the power by the selection designating means. It is possible to allow the cutoff to the electric equipment which does not interfere even if the electric power is cut off, and not to cut off the electric equipment to which the power supply is not desired to be cut off.

Further, if threshold value setting means for setting the threshold value is provided, the user can freely set the threshold value according to the rated current of the electric equipment to be used. Will be able to.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows an external appearance of the power distribution device 1 according to this embodiment, and FIG. 1 shows a schematic electric circuit configuration of the power distribution device 1. First, in FIG. 2, reference numeral 2 denotes a main body case in the shape of a thin rectangular box, and a power cord 3 having a power plug 3a at its tip is led out from the rear surface of the main body case 2. The power plug 3a is adapted to be connected to a power supply line (outlet) (not shown) having a relatively small power capacity (for example, rated operating current is 15A).

On the front surface of the main body case 2, for example, three power supply ports 4, 5 and 6 to which electric devices (not shown) are connected are provided like outlets. In this case, the power supply port 4 located on the left side in the drawing is used as a monitor port (hereinafter referred to as monitor output port 4). An up / down key 7 for setting a threshold value is provided on the upper surface of the main body case 2 in correspondence with the monitor output port 4, and an LCD or the like for displaying the threshold value is displayed. A section 8 is provided. Although described in detail later, the up / down key 7 functions as the threshold value setting means in the present invention.

On the upper surface of the body case 2, setting switches 9 and 10 are provided corresponding to the power supply ports 5 and 6, respectively, and the neon lamp 1 is provided.
1 and 12 are provided. As will be described later, the setting switches 9 and 10 are normally turned off, but are turned on only when the user does not want the power supply to be cut off. It functions as the selection designating means in the present invention. The neon lamps 11 and 12 are for lighting and indicating whether the corresponding power supply ports 5 and 6 are supplied with power or shut off. Further, a main switch 13 is provided on the upper surface of the body case 2.

As shown in FIG. 1, the fuse 16 and the main switch 1 are connected to one power supply line 14 of the two power supply lines 14 and 15 continuous with the power cord 3.
3 is inserted in series, and its tip is branched and connected to one terminal of each of the power supply ports 5 and 6 and the monitor output port 4. The other power supply line 15 is branched and connected to the other terminals of the power supply ports 5 and 6 and the monitor output port 4, respectively.

At this time, the setting switch 9 and the relay switch 17 are inserted in parallel between one terminal of the power supply port 5 and the branch line of the power supply line 14, and the power supply port is provided. The setting switch 10 and the relay switch 18 are also provided between one terminal of 6 and the branch line of the power supply line 14.
And are inserted in parallel. Also, the neon lamp 1
1 is turned on when at least one of the setting switch 9 and the relay switch 17 is on, and is turned off only when both of them are off.
Similarly, the neon lamp 12 is turned on when at least one of the setting switch 10 and the relay switch 18 is on, and is turned off only when both of them are off.

A control circuit 19 including a microcomputer is provided in the main body case 2. As shown in FIG. 1, a signal from the up / down key 7 is input to the control circuit 19, and
The display unit 8 is controlled by the control circuit 19. Further, the control circuit 19 controls the relay switches 17 and 18 to be turned on and off.

The used current value at the monitor output port 4 is detected by the current detecting element 20 which is a current detecting means, and the detection signal of the current detecting element 20 is inputted to the control circuit 19. There is. Due to its software configuration, the control circuit 19 normally turns on the relay switches 17 and 18, and the detected current value of the current detection element 20 becomes the up / down key 7
The relay switches 17 and 18 are turned off and the power supply to the power supply ports 5 and 6 is cut off when the threshold value set by the above and displayed on the display unit 8 is exceeded. Therefore, the control circuit 19 functions as the current limiting means in the present invention.

Next, the operation of the above configuration will be described with reference to FIG. For example, electric appliances such as a refrigerator, a water heater, and a microwave oven are installed in a cafeteria, a water heater, etc. of a company office. Here, the rated current of the refrigerator is about 5 A (when driving the motor), the rated current of the water heater is about 6 A (when boiling water),
The rated current of the microwave oven is about 12 A, and if the three are used at the same time, the rated operating current of 15 A will be exceeded.

Therefore, a microwave oven is connected to the monitor output port 4 of the power distribution device 1, and a refrigerator and a water heater are connected to the power supply ports 5 and 6, respectively. Further, since the current consumption of the microwave oven is 1 A or less when the magnetron is stopped, the threshold value is set to 1 A by operating the up / down key 7 while observing the display unit 8. At this time, the setting switches 9 and 10 are turned off.

Now, as shown in the flow chart of FIG. 3, the control circuit 19 always determines whether or not the current value used at the monitor output port 4 exceeds the threshold value (1 A) by the detection signal of the current detection element 20. It is being monitored (step S1). In the state where the microwave oven is not used, the current consumption at the monitor output port 4 is 1 A or less (No in step S1).
And 18 are turned on (step S2), and power is supplied to the power supply ports 5 and 6. In this case, even if the refrigerator and the water heater are used, the maximum consumption current is 1A + 5A + 6A = 12A, which does not exceed the rated use current 15A.

When the microwave oven (magnetron) is operated, the current detected by the current detecting element 20 is 1A.
(Step S1 is Yes), the relay switches 17 and 18 are instantly turned off (step S3). As a result, the power supply to the power supply ports 5 and 6 is cut off. Even in this case,
The maximum current consumption is only 12A of the microwave oven. Further, since the microwave oven is used for a relatively short time, when the use of the microwave oven is finished, the detected current of the current detection element 20 becomes 1 A or less again, and the power supply port 5
And 6 will be supplied.

As described above, the current consumption of the three types of electric equipment is always 12 A or less, and the rated operating current is 15 A.
Even if it is small, the current usage of 3 A is always secured for other office equipment. Further, when the microwave oven is used, the refrigerator and the water heater are temporarily stopped, but even if the power supply is temporarily cut off, they do not significantly affect actual use.

If the rated operating current is 20 A, for example, even when the microwave oven (rated current 12 A) is used, the refrigerator (5 A) can be operated at 3 A for office equipment without shutting off the power supply. A current can be secured. In such a case, if the setting switch 9 is turned on, the power supply to the power supply port 5 will not be cut off even if the relay switch 17 is turned off, and the power supply is cut off. It will be performed only at the port 6 for use, and it will be more convenient.

As described above, according to the present embodiment, the current detecting element 20 detects the current used by the electric equipment connected to the monitor output port 4, and when the current value exceeds the threshold value, another current is detected. Since the power supply to the power supply ports 5 and 6 is cut off, it is possible to prevent the rated operating current from being exceeded without causing a serious problem in the use of the electric device. Therefore, unlike the conventional one in which the breaker may operate by exceeding the rated operating current, the rated operating current may be exceeded even in a power supply line with a relatively small power supply capacity. It is possible to use electric devices without concern.

Further, particularly in the present embodiment, the setting switches 9 and 10 are provided so that the user can selectively specify the power supply ports 5 and 6 whose power supply is cut off. It is possible to allow interruption to electric equipment that can be temporarily cut off and not to cut off to electric equipment that does not want power supply to be cut off. It will be convenient.

Further, in this embodiment, the threshold value can be arbitrarily set by the up / down key 7 and the display unit 8, so that the user can set the rated current of the electric equipment to be used. Accordingly, the threshold value can be freely set, and the usability is further improved.

In the above embodiment, the threshold value can be set arbitrarily, but the threshold value is set to 1
Even if the structure is fixed to A, the intended purpose can be achieved. Further, the setting switches 9 and 10 are provided so that the user can selectively specify the power supply ports 5 and 6 whose power supply is cut off. However, the setting switches correspond to all the power supply ports. It is also possible to achieve the intended purpose even without providing a setting switch.

In addition, the present invention is not limited to the above-described embodiment, and for example, two or more monitor output ports may be provided, and the number of power supply ports may be increased as necessary. The present invention can be implemented by appropriately changing it within a range not departing from the gist of the invention.

[0030]

As is apparent from the above description, according to the power distribution device of the present invention, the current detecting means for detecting the used current value in the predetermined power supply port among the plurality of power supply ports, Since the current limiting means for shutting off the power supply to the other power supply port when the used current value detected by the current detection means exceeds the threshold value,
Even in a power supply line having a comparatively small power supply capacity, it has an excellent practical effect that an electric device can be used without being concerned about exceeding the rated use current.

Further, in this case, if the selection designating means for selectively designating the power supply port for which the power supply is cut off by the current limiting means is provided, the electric equipment in which the power supply is not desired to be cut off is provided. It will be more convenient because it will not be necessary to block it.

Furthermore, by providing a threshold value setting means for arbitrarily setting the threshold value, the threshold value can be set freely according to the rated current of the electric equipment used. The usability is further improved.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is a diagram showing an electric circuit configuration of a power distribution device.

FIG. 2 is a perspective view showing the appearance of a power distribution device.

FIG. 3 is a flowchart showing a processing procedure of a control circuit.

[Explanation of symbols]

In the drawing, 1 is a power distribution device, 2 is a main body case, 4 is a monitor output port (predetermined power supply port), 5 and 6 are power supply ports, 7 is an up / down key (threshold setting means), 8 Is a display section, 9 and 10 are setting switches (selection designating means), 17 and 18 are relay switches, 19 is a control circuit (current limiting means), and 20 is a current detecting element (current detecting means).

Claims (3)

[Claims] 1. A power supply device, comprising: a plurality of power supply ports to which an electric device is connected; power being distributed to each of the power supply ports and supplied; Current detection means for detecting a current value used in the power supply port, and current limit for cutting off power supply to another power supply port when the current value detected by the current detection means exceeds a threshold value. A power distribution device comprising: 2. The power distribution device according to claim 1, further comprising selection designation means for selectively designating a power supply port whose power supply is cut off by the current limiting means. 3. The power distribution device according to claim 1, further comprising threshold setting means for setting a threshold arbitrarily.