JPH0833188A - Electrical apparatus operated by ac adapter - Google Patents

Abstract

PURPOSE:To prevent a fault by cutting power supply when it is judged that the detected output voltage of an AC adapter is higher than a predetermined upper limit value for the input. CONSTITUTION:An adapter output voltage Vout fed from a power supply voltage detection circuit is converted to a digital value by an A/D converter (S110) and is stored in an internal RAM (120). Then, it is judged whether the adapter output voltage Vout is higher than an input upper-limit voltage V1 or not (130). On the other hand, when the adapter output voltage Vout is higher than the input upper-limit voltage V1, a message that the upper-limit voltage is exceeded appears on an LCD (150) and the power is turned off in a specific amount of time (170). When a voltage exceeding a certain level is applied, a fault may occur. Therefore, the fault can be prevented in advance by cutting power supply.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can be connected to an AC adapter for stepping down an AC power supply and converting it to DC.
The present invention relates to an electric device that operates with a DC power source of a C adapter.

[0002]

2. Description of the Related Art Conventionally, in portable equipment such as word processors, tape recorders and radios,
Some can be operated by a DC power source such as a dry battery or a storage battery, and others can be operated by connecting an AC adapter for stepping down the AC power source and converting it into a DC voltage so that the AC power source can be used. The DC voltage required to operate these electric devices may be, for example, two 1.5 V dry cells (that is, 3 V) or 3
The number of lines (that is, 4.5V), the number of lines (that is, 6V), and the number of lines (that is, 9V) are sometimes required, and are not necessarily constant.

Therefore, the AC adapter is also for 3V, 4.5
Different output voltages are made such as V, 6V and 9V. Also, it is not only an integral multiple of 1.5V, but for example 7.5V or 8V,
There is also an AC adapter dedicated to the electric device. In this case, some batteries are designed to operate only with an AC adapter without using dry batteries.

[0004]

However, in such a conventional AC adapter, if the output voltage is the same, the shapes of the connection terminals are not all the same, and conversely, if the output voltage is different, it is always necessary. There is no difference in the shape of the connection terminals. Therefore, for example, it is possible to connect an AC adapter for 6V to an electric device that is operated by a DC power source of 4.5V, and a small one for output voltage of 9V or higher, or for 3V. It may be possible to connect the one with output voltage. In the case of dry batteries, for example, how many 1.5V batteries should be installed, and it is impossible to install more than the required number because it is easy to see how many batteries are needed at a glance. Further, it can be immediately understood that the number is insufficient if the number is less than or equal to the required number, but in the case of the adapter, the determination cannot be made without looking at the voltage display of the connected device and the adapter.

As described above, when using dry batteries or the like, it is unlikely that the wrong number of batteries will be installed.
In the case of an AC adapter, there is a high possibility that it may be accidentally connected. When an AC adapter having an output voltage smaller than the required voltage of the electric device is used, the electric device does not operate or becomes an abnormal operating state even if the electric device operates. Therefore, if the AC adapter that is not operating is connected to the wrong AC adapter, it may not be immediately noticed, and there is a possibility that the electric device itself may be erroneously determined to be a failure. Further, in the case where the operation itself is performed even if it is abnormal, for example, in a device that prints while driving the platen with a motor, the rotation of the platen becomes slower than usual, and printing may not be successful. Further, in the case of a tape reproducing device or the like, the rotation becomes slower than usual and the reproduced sound may not be heard.

On the other hand, when an AC adapter having an output voltage higher than the required voltage of the electric equipment is used, an excessive voltage is applied to the electric equipment, which may cause a failure or the like. Then, this invention aims at solving the said subject, and when an improper AC adapter is connected, it provides the electric equipment provided with the fail-safe function which cuts off a power supply or issues an alarm. Especially.

[0007]

The invention according to claim 1 made to achieve the above object is connectable to an AC adapter for stepping down the AC power supply and converting it to DC.
In an electric device operated by the DC power source of the AC adapter, the output voltage detection means for detecting the output voltage of the connected AC adapter and the output voltage of the AC adapter detected by the output voltage detection means are An upper limit voltage abnormality determining means for determining whether or not a predetermined input upper limit voltage of the device is exceeded, and the upper limit voltage abnormality determining means determines that the output voltage of the AC adapter exceeds the input upper limit voltage. In this case, the electric device is provided with a power supply cutting means for cutting the power supply from the AC adapter.

According to a second aspect of the invention, in the electric device according to the first aspect, the upper limit voltage abnormality determining means determines that the output voltage of the AC adapter exceeds the input upper limit voltage. In this case, an upper limit voltage abnormality notifying means for notifying that effect is provided, and the power supply cutting means cuts off the power supply after the notification by the upper limit voltage abnormality notifying means.

The invention according to claim 3 can be connected to an AC adapter for stepping down an AC power supply and converting it to a DC power supply. In an electric device which is operated by the DC power supply of the AC adapter, the connected AC adapter is connected. Output voltage detecting means for detecting the output voltage of and the lower limit voltage abnormality for judging whether or not the output voltage of the AC adapter detected by the output voltage detecting means is below a predetermined input lower limit voltage of the electric device. And a lower limit voltage abnormality notifying unit for notifying that the output voltage of the AC adapter is below the input lower limit voltage by the lower limit voltage abnormality determining unit. It is an electric device characterized by.

The invention according to claim 4 is the same as claim 3
In the electric device described in (1) above, there is provided power supply cutoff means for cutting off the power supply from the AC adapter after the notification by the lower limit voltage abnormality notification means.

Further, the invention according to claim 5 can be connected to an AC adapter for stepping down an AC power supply and converting it to a DC power supply, and in the electric equipment which is operated by the DC power supply of the AC adapter, the connected AC adapter is connected. Output voltage detecting means for detecting the output voltage of the above, and an upper limit voltage abnormality for judging whether or not the output voltage of the AC adapter detected by the output voltage detecting means exceeds a predetermined input upper limit voltage of the electric device. When the determining means and the upper limit voltage abnormality determining means determine that the output voltage of the AC adapter exceeds the input upper limit voltage, the upper limit voltage abnormality notifying means for notifying the fact and the output voltage Lower limit for determining whether or not the output voltage of the AC adapter detected by the detecting means is below a predetermined input lower limit voltage of the electric device When the pressure abnormality determining means and the lower limit voltage abnormality determining means determine that the output voltage of the AC adapter is lower than the input upper limit voltage, a lower limit voltage abnormality notifying means for notifying the fact, It is an electric device comprising: a power supply cutting means for cutting off the power supply from the AC adapter after the notification by the upper limit voltage abnormality notifying means or the lower limit voltage abnormality notifying means.

[0012]

According to the electronic device of the present invention having the above-mentioned structure, the output voltage detecting means detects the output voltage of the connected AC adapter, and the upper limit voltage abnormality judging means detects it. It is determined whether the output voltage of the AC adapter exceeds a predetermined input upper limit voltage of the electric device. Then, when it is determined that the output voltage of the AC adapter exceeds the input upper limit voltage, the power supply cutting means cuts the power supply from the AC adapter.

When an AC adapter having an output voltage higher than the required voltage of the electric equipment is used, an excessive voltage is applied to the electric equipment, which may cause a failure. In that case, the power supply is cut off to prevent the failure.

When it is determined that the output voltage of the AC adapter exceeds the input upper limit voltage, the upper limit voltage abnormality notifying means notifies the fact and then supplies power. May be cut. If you suddenly cut off the power supply, you may mistakenly think that the electric device does not work for some other reason, so after notifying that the cause is that an incorrect AC adapter was connected, the power supply If the supply is cut, it will be kind to users.

According to another aspect of the electronic device of the present invention, the output voltage detecting means detects the output voltage of the connected AC adapter, and the lower limit voltage abnormality determining means determines that the detected output voltage of the AC adapter is normal. It is determined whether or not the voltage is below a predetermined input lower limit voltage of the electric device. Then, when it is determined that the output voltage of the AC adapter is lower than the input upper limit voltage, the lower limit voltage abnormality notifying means notifies that fact.

When the voltage exceeds the upper limit voltage as in the above-mentioned claim 1, if it is left as it is, it may cause a failure of the electric equipment. Therefore, the main purpose is to cut off the power supply. Then, it is more preferable to notify that effect. On the other hand, when the voltage is below the lower limit voltage, the electric device does not operate, or even if it operates, the motor rotates, for example, slower than usual. Therefore, for example, A
In order to prevent the user from not immediately recognizing that the C adapter is connected and erroneously determining that the electric device itself is out of order, the main purpose is to notify.

When it is determined that the output voltage of the AC adapter is lower than the input upper limit voltage, it is preferable to cut off the power supply after notifying the fact. . In this case, although it does not directly lead to a failure of the electric device such as when the above upper limit voltage is exceeded, for example, if the motor is continuously rotated at a slow speed, in the case of a tape recorder or the like, defective recording or defective reproduction occurs. Therefore, it is practically preferable to automatically stop.

According to the present invention, the output voltage detecting means detects the output voltage of the connected AC adapter,
The upper limit voltage abnormality determining means determines whether or not the detected output voltage of the AC adapter exceeds a predetermined input upper limit voltage, and the lower limit voltage abnormality determining means determines that the output voltage has a predetermined input lower limit voltage. It also judges whether it is below the level.
Then, when it is determined that the output voltage of the AC adapter exceeds the input upper limit voltage, the upper limit voltage abnormality notifying means notifies that, and similarly, the output voltage of the AC adapter is lower than the input lower limit voltage. If it is determined that, the lower limit voltage abnormality notifying means notifies that fact. In each case, the power supply cutting means cuts the power supply from the AC adapter after the corresponding notification is given.

In reality, it is inappropriate to exceed the upper limit voltage or fall below the lower limit voltage. Therefore, it is preferable to have a coping function for both cases.
As described above, the electric device of the present invention has a fail-safe function of cutting off power supply or issuing an alarm when an inappropriate AC adapter is connected.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows an example of an electric device according to the present invention.
FIG. 1 is a front view of a label producing apparatus 1 capable of printing a large number of characters such as kanji, hiragana, katakana, alphabetic characters and symbols on a printing tape (printing medium) 5.

As shown in FIG. 1, a keyboard 3 is provided in the front part of the main body frame 2 of the label producing apparatus 1, and a printing mechanism PM is provided in the main body frame 2 behind the keyboard 3 and the keyboard 3 is provided. Behind 3 is provided a liquid crystal display (LCD) 22 capable of displaying characters and symbols.

Further, the label producing apparatus 1 is designed to be operated by a DC power source, and a connector portion for connecting an output terminal 71 of the AC adapter 70 is provided on the rear side surface of the main body frame 2. . The AC adapter 70 includes a plug 73 that is connected to an AC power source.
AC power supplied from 3 is transformed and rectified,
The DC voltage subjected to the transformer rectification is controlled to a constant voltage and output from the output terminal 71.

On the other hand, to further explain the label producing apparatus 1, the keyboard 3 has a character input key for inputting characters such as alphabets, numbers and symbols, a cursor movement key 50, a return key 51 for line feed or decision. A print execution key for executing printing, a power supply key 54 for turning on / off the power supply, and the like are provided.

The printing mechanism PM will be briefly described with reference to FIG. 2. A rectangular tape storage cassette CS is detachably attached to the printing mechanism PM, and the tape storage cassette CS is transparent. A tape spool 6 around which a printing tape 5 made of a film is wound, a ribbon supply spool 8 around which an ink ribbon 7 is wound, a take-up spool 9 around which the ink ribbon 7 is wound, and a printing tape 5
A supply spool 11 in which a double-sided tape 10 having the same width as that of the release tape is wound outside, and these printing tapes 5
A joining roller 12 for joining the double-sided tape 10 and the double-sided tape 10 is rotatably provided.

A thermal head 13 is erected at a position where the printing tape 5 and the ink ribbon 7 overlap each other, and the thermal head 13 connects the printing tape 5 and the ink ribbon 7 to each other.
A platen roller 14 that presses the printing tape 5 and the double-sided tape 10 against the joining roller 12 are rotatably supported by a support body 16.

A cassette discriminating member 17 for setting the type of the tape accommodating cassette CS, that is, the tape width of the accommodated printing tape 5 is attached to the bottom wall of the tape accommodating cassette CS. A cassette discrimination sensor 18 (see FIG. 3) including a photo interrupter for detecting a provided protruding piece (not shown)
Are attached to the body frame 2. Therefore, the tape width can be detected based on the discrimination signal from the cassette discrimination sensor 18.

Next, the control system of the label producing apparatus 1 is shown in FIG.
The block diagram of FIG. A display R for outputting display data to the keyboard 3, the cassette discrimination sensor 18, and the liquid crystal display (LCD) 22.
Display controller (LCDC) 2 with AM
3 and a drive circuit 2 for driving the thermal head 13
5 and a drive circuit 26 for driving the tape feed motor 24 are connected to an input / output interface 27 of the controller C, respectively. The control device C includes a CPU 29, an input / output interface 27 connected to the CPU 29 via a bus 28 such as a data bus, a CGROM 30,
It is composed of ROMs 31, 32 and RAM 40.

CGROM (pattern data memory) 30
In FIG. 5, dot pattern data for display is stored in association with code data for each of a large number of characters. Further, in the ROM (outline data memory) 31, for each of a large number of characters for printing characters, outline data (outline data) that defines the outline of the character is included in a typeface (Gothic typeface, Mincho typeface). Etc.) and is stored corresponding to the code data.

Then, in the ROM 32, the label producing apparatus 1
Stores a program for operating. Further, a predetermined input upper limit voltage V in the label producing apparatus 1
The data of 1 and the input lower limit voltage V2 are also stored. The input upper limit voltage V1 and the input lower limit voltage V2 will be described.
The voltage required for the label producing apparatus 1 to operate is fixed. If a voltage greater than a predetermined voltage higher than the required voltage is applied, it may cause a failure or the like.
Although it depends on how much margin is taken depending on the device, for example, the required voltage is 8V and the input upper limit voltage V1 is about 12V.

On the other hand, when a voltage lower than a predetermined voltage lower than the required voltage is applied, it often does not directly lead to a failure like the case where the upper limit voltage V1 is exceeded, but the device itself does not operate, or For example, if the label producing apparatus 1 is operated, the tape feeding motor 24
Is rotated slower than usual, so that normal printing cannot be performed. Therefore, the lower limit voltage V2 also changes depending on how much margin is taken depending on the device. For example, the required voltage is 8V, and the input lower limit voltage V2 is
Is about 6.4V.

Further, the text memory area 4 of the RAM 40
1 stores character data input from the keyboard 3. In the print buffer area 47, the data of the print dot pattern in which the image is developed is stored. Further, the RAM 40 is provided with a work area for temporarily storing the calculation result calculated by the CPU 29, a buffer, an area for a counter, a pointer, and the like.

Next, the structure of the power supply system will be described with reference to FIG. The predetermined DC power from the output terminal 71 of the AC adapter 70 described above is supplied to the power supply circuit 83 via the power supply voltage detection circuit 80 and the switch section 81 in the control device C. The power supply voltage detection circuit 80 corresponds to the output voltage detection means. The switch unit 81 includes a switch that operates mechanically, and disconnects the switch by an OFF signal from the CPU 29 in the control device C. When the switches are connected, the switch unit 21 supplies the power supply circuit 83 with the power of the voltage output from the AC adapter 70 as it is. The switch unit 81 corresponds to a part of the power supply cutting means.

The power supply circuit 83 includes a booster circuit 85 and a stabilizing circuit 87, and the booster circuit 85 raises the voltage to a predetermined voltage and supplies it to the printing mechanism PM. The thermal head 13 and the tape feed motor 24 are mainly consumed by their operation, but they are also necessary for the drive circuits 25 and 26.

On the other hand, the stabilizing circuit 87 lowers the voltage to a predetermined voltage and supplies a stable power supply voltage to the controller C.
For example, when the DC power of 9V is supplied from the AC adapter 70, the booster circuit 85 boosts the voltage to 12V,
In the stabilization circuit 87, the voltage is stepped down to 5V.

The power supply voltage detection circuit 80 detects the voltage supplied from the AC adapter 70 and sends it to the CPU 29.
In the CPU 29, it is converted into a digital value by the internal A / D converter, stored in the internal RAM, and used for the power supply control process described later. Next, the operation of the label producing apparatus 1 particularly relating to power supply control will be described with reference to the flowcharts of FIGS.

When the power is turned on by operating the power key 53, the label producing apparatus 1 starts its operation. When the operation is started, the CPU 29 first initializes each data in the RAM 40 according to the program of the ROM 32, and also initializes the edit screen (step 10, hereinafter, the step is simply referred to as S). In this embodiment, up to two lines can be displayed on the liquid crystal display 22, and when initialized, a line head mark and a cursor are displayed on the liquid crystal display 22.

Then, a voltage check process is performed (S2
0). The voltage check process will be described later with reference to FIG. When the process returns to the main process after the voltage check process, in S30, it is determined whether or not a key input is made from the keyboard 3, and if there is any key input, the process exits S30 and is detected. After performing the process corresponding to the key operation (S40), the process returns to S20. The process corresponding to the key operation is, for example, if the character key is operated, the character data corresponding to the key is RA
This is a process of storing in the text memory area 41 of M40 and inserting and displaying the input character on the screen of the liquid crystal display 22. Other, cursor movement key 50
The cursor is moved, the printing process or the like is performed according to the operation of the return key 51, the print execution key 52, or the like. Since these processes are general ones, their explanation is omitted here.

Next, the detailed contents of the voltage check process of S20 will be described with reference to the flowchart of FIG. In the voltage check process, first, the power supply voltage detection circuit 80
The adapter output voltage Vout sent from A / D is converted into a digital value (S110), and the adapter output voltage Vout is stored in the internal RAM (S120).

Then, the input upper limit voltage V1 stored in the ROM 32 is read to determine whether the adapter output voltage Vout is larger than the input upper limit voltage V1 (S13).
0). When the adapter output voltage Vout is less than or equal to the input upper limit voltage V1 (S130: NO), the input lower limit voltage V2 stored in the ROM 32 is read to determine whether the adapter output voltage Vout is less than the input lower limit voltage V2. Yes (S140). Here, when the adapter output voltage Vout is equal to or higher than the input lower limit voltage V2 (S140: NO), V2
≦ Vout ≦ V1, which is within the allowable range from the viewpoint of the voltage required for the label producing apparatus 1 to operate, so the process directly returns to the main process (FIG. 5).

On the other hand, if an affirmative judgment is made in S130, that is, if the adapter output voltage Vout is larger than the input upper limit voltage V1, a display indicating that the upper limit voltage is exceeded is displayed on the liquid crystal display (LCD) 22 (S150), The power is turned off after a predetermined time (S170). If the determination in S140 is affirmative, that is, if the adapter output voltage Vout is smaller than the input lower limit voltage V1, a display indicating that it is below the lower limit voltage is displayed on the liquid crystal display (LCD) 22 (S160), and after a predetermined time. Turn off the power (S1
70).

As described above, the label producing apparatus 1 detects the output voltage Vout of the connected AC adapter 70 and determines whether the detected adapter output voltage Vout exceeds the predetermined input upper limit voltage V1. It is also determined whether the adapter output voltage Vout is below a predetermined input lower limit voltage V2. Then, if it is determined that the adapter output voltage Vout exceeds the input upper limit voltage V1, and if it is determined that it is below the input lower limit voltage V2, it is an upper limit voltage abnormality and a lower limit voltage abnormality, respectively. A message is displayed on the liquid crystal display (LCD) 22 to notify the user. In each case, after the corresponding notification is given, the switch unit 81 is controlled so that power is not supplied to the power supply circuit 83 side.

In the case of the present embodiment, when the AC adapter 70 having an output voltage larger than the required voltage of the label producing apparatus 1 is used, a voltage more than necessary is applied to the label producing apparatus 1, which causes a failure or the like. Because it may cause
In that case, the power supply is cut off to prevent the failure. Also, if you suddenly cut off the power supply,
There is a possibility that you may mistakenly think that it does not work for some other reason, so if you cut off the power supply after notifying that it is due to connecting an inappropriate AC adapter 70, you can tell the user. I am kind to you.

Further, in the case of the present embodiment, even when the voltage is below the lower limit voltage V2, the abnormality is similarly displayed and then the power supply is cut off. As described above, the upper limit voltage V
If it exceeds 1, it may cause a failure if left as it is, so the main focus is to cut off the power supply. Then, it is more preferable to notify that effect. On the other hand, when the voltage is below the lower limit voltage, the label producing apparatus 1 does not operate, or even if it operates, the tape feeding motor 24 or the like rotates slower than usual. Therefore, for example, in order to prevent the operator from not immediately recognizing that the AC adapter is erroneous when the AC adapter is erroneous and is not mistakenly determined to be a failure of the electric device itself, the main purpose is to notify. However, if the tape feed motor 24 is rotated at a slow speed, for example, printing failure may occur. Therefore, it is practically preferable to stop the tape feeding motor 24 automatically.

The CPU 29 corresponds to the upper limit voltage abnormality determining means, the lower limit voltage abnormality determining means, the upper limit voltage abnormality notifying means, the lower limit voltage abnormality notifying means, and the power supply cut means of the present invention. , Above S110
~ S130 corresponds to the process as upper limit voltage abnormality determining means, and S110, S120, S140 corresponds to the process as lower limit voltage abnormality determining means. Further, S150 corresponds to the process as the upper limit voltage abnormality notifying unit, and S160 corresponds to the process as the lower limit voltage abnormality notifying unit. And S1
Reference numeral 70 corresponds to a process as a power cut means.

The present invention is not limited to the embodiments as described above, and can be carried out in various modes without departing from the scope of the present invention. For example, in the above-described embodiment, the label producing apparatus 1 is described as an example, but the present invention is not limited to such an apparatus, and any electrical equipment that operates with a DC power source of an AC adapter may be used, for example, a word processor, a tape recorder, a radio. Etc. can be similarly implemented.

[Brief description of drawings]

FIG. 1 is a perspective view showing an overall configuration of a label producing apparatus as an example.

FIG. 2 is a schematic plan view of a printing mechanism of the label producing apparatus of the embodiment.

FIG. 3 is a block diagram of a control system of the label producing apparatus according to the embodiment.

FIG. 4 is a block diagram of a power supply system of the label producing apparatus according to the embodiment.

FIG. 5 is a flowchart of a main routine in the embodiment.

FIG. 6 is a flowchart of a voltage check routine in the embodiment.

[Explanation of Codes] 1 ... Label producing device 3 ... Keyboard 5 ... Printing tape 13 ... Thermal head 22 ... Liquid crystal display 24 ... Tape feed motor 25 ... (Thermal head) drive circuit 26 ... (Tape feed motor) Drive circuit 29 ... CPU 30 ... ROM 70 ... AC adapter 71 ... Output terminal 73 ... Plug 80 ... Power supply voltage detection circuit 81 ... Switch section 83 ... Power supply circuit 85 ... Booster circuit 87 ... Stabilization circuit C ... Control device PM ... Printing mechanism

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location G06F 1/28 1/30 (72) Inventor Kengo Omura 3-46, Osu, Naka-ku, Nagoya-shi, Aichi No. 15 Brother Systems Co., Ltd.

Claims (5)

[Claims] 1. A for stepping down an AC power supply and converting it to a DC
In an electric device that is connectable to a C adapter and operates by a DC power source of the AC adapter, output voltage detecting means for detecting an output voltage of the connected AC adapter, and the AC detected by the output voltage detecting means. An upper limit voltage abnormality determining means for determining whether or not the output voltage of the adapter exceeds a predetermined input upper limit voltage of the electric device, and the output voltage of the AC adapter is determined by the upper limit voltage abnormality determining means. And a power supply cut-off means for cutting off the power supply from the AC adapter when it is determined that the electric equipment is out of the range. 2. When the upper limit voltage abnormality determining means determines that the output voltage of the AC adapter exceeds the input upper limit voltage, an upper limit voltage abnormality notifying means is provided for notifying the fact, The electric device according to claim 1, wherein the power supply cutting means cuts the power supply after the notification by the upper limit voltage abnormality notifying means. 3. A for stepping down the AC power supply and converting it to DC
In an electric device that is connectable to a C adapter and operates by a DC power source of the AC adapter, output voltage detecting means for detecting an output voltage of the connected AC adapter, and the AC detected by the output voltage detecting means. The lower limit voltage abnormality determining means for determining whether or not the output voltage of the adapter is lower than a predetermined input lower limit voltage of the electric device, and the lower limit voltage abnormality determining means determines that the output voltage of the AC adapter is the input lower limit voltage. When it is determined that the electric power is below the lower limit, an electric device characterized by comprising: a lower limit voltage abnormality notifying means for notifying that effect. 4. The electric device according to claim 3, further comprising a power supply cutting means for cutting off the power supply from the AC adapter after the notification by the lower limit voltage abnormality notifying means. . 5. A for stepping down an AC power supply and converting it to DC
In an electric device that is connectable to a C adapter and operates by a DC power source of the AC adapter, output voltage detecting means for detecting an output voltage of the connected AC adapter, and the AC detected by the output voltage detecting means. An upper limit voltage abnormality determining means for determining whether or not the output voltage of the adapter exceeds a predetermined input upper limit voltage of the electric device, and the output voltage of the AC adapter is determined by the upper limit voltage abnormality determining means. If it is determined that the output voltage exceeds the upper limit voltage abnormality notifying means for notifying the fact, and the output voltage of the AC adapter detected by the output voltage detecting means is a predetermined input lower limit voltage in the electric device. Lower limit voltage abnormality determining means for determining whether or not the output voltage of the AC adapter is reduced by the lower limit voltage abnormality determining means. When it is determined that the pressure is lower than the input upper limit voltage, the lower limit voltage abnormality notifying means for notifying that, and after the upper limit voltage abnormality notifying means or the lower limit voltage abnormality notifying means is notified, An electric device comprising: a power supply cutting means for cutting the power supply from the AC adapter.