JP4120498B2 - Attached equipment of electronic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an option (attached device) for an electronic device.
[0002]
[Prior art]
In general, a technique for smoothly switching power sources that enables power supply from two or more power sources so that the operation does not become unstable is known (for example, see Patent Document 1).
[0003]
On the other hand, in recent years, it has been known that two or more options (hardware) can be mounted on a multifunction peripheral (having a multi-function such as a facsimile machine and a copying function), a computer, and the like.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-91841
[Problems to be solved by the invention]
In an electronic device to which an option is attached, whether the power from the apparatus body can be covered by the number of the option or the combination, or whether an external power source is required is changed. When an external power supply is required, it is necessary to make a setting for switching from the power supply from the apparatus main body to the external power supply. In general electronic equipment, simply plugging in the AC adapter will switch to an external power supply, but depending on the number and combination of options, only the power supply of the main body of the apparatus or whether an external power supply is required differs as described above. It cannot be switched by simply plugging / unplugging the AC adapter as in a general electronic device. For example, options are fully connected and each option needs to be powered from an external power supply. Even if the AC adapter is connected, if the settings are turned on to the main unit power supply, the operation will start as is, and It is not possible to know that the power is being used.
[0006]
The present invention was made in view of the above problems, in addition to the apparatus main body, when used in combination with option causes reliably perform switching between connection and switch the external power supply, shortage of power capacity It is an object of the present invention to provide an option (attached device) for an electronic device that can prevent an option malfunction due to a voltage drop caused by the above.
[0007]
[Means for Solving the Problems]
The electronic device accessory device according to the present invention has an internal power supply from the device main body to be mounted, a shaft terminal, a contact terminal, and a contact terminal. A jack for receiving, a changeover switch for selectively outputting one of an internal power supply from the apparatus main body and an external power supply from the AC adapter, and a contact terminal of the jack connected to a CLR terminal. The output voltage is received at the CK terminal, the D terminal is connected to the reference potential, and the power supply voltage output from the changeover switch or the external power supply voltage from the jack is received at the PR terminal via the delay element. Flip-flop, the change-over switch is turned on to the internal power supply side of the apparatus body, and the AC adapter plug Is not inserted into the jack, a signal from the contact terminal of the jack is input to the CLR terminal to reset the D-type flip-flop, indicating that the external power supply is not normal. when outputting the first logic state of the signal ( "L" signal), the change-over switch are turned to the internal power source side of the device the body, and the plug of the AC adapter is inserted into the jack, said external power supply voltage via the delay element from the shaft pin of the jack being applied to the PR terminal the D-type flip-flop is preset, the on subsequent internal power supply, the via the changeover switch from the internal power supply the D-type flip-flop in response to turn on the power input to the CK terminal is reset by the output signal of said first logic state, wherein Over switch has been turned to the external power supply side, and when the plug of the AC adapter is inserted into the jack, said external power supply voltage is applied to the PR terminal via the delay element from the shaft pin of the jack Before the external power supply voltage is input to the CK terminal through the change-over switch, the D-type flip-flop is set, and the second logic state indicates that the supply of the external power supply is normal. A signal ([H] signal) is output.
[0008]
When it is necessary to use an external power source in the electronic apparatus accessory device of the present invention, if the AC adapter plug is inserted into the jack and the external power source is selected by the changeover switch, the D-type flip-flop Before the external power supply voltage is applied to the PR terminal via the delay element from the jack shaft terminal, the external power supply voltage is set by being input to the CK terminal via the changeover switch, so that the external power supply is normal. A signal in a second logic state ([H] signal) indicating that there is a signal is output. The signal in the second logic state can be sent to the main unit, and normal can be displayed on the display unit of the main unit.
On the other hand, when the changeover switch is turned on to the internal power supply side of the apparatus body and the plug of the AC adapter is not inserted into the jack, the D-type flip-flop receives a signal from the jack contact terminal at the CLR terminal. It is reset by being input, and outputs a first logic state signal ("L" signal) indicating that the external power supply is not normal. This first logic state signal is sent to the main unit, and an abnormality is displayed on the display unit of the main unit.
Further, the change-over switch has been turned to the internal power source side of the device main body, and when the plug of the AC adapter is inserted into the jack, D-type flip-flop, the external power supply voltage is the axis pin of the jack preset is applied via a delay element to the PR terminal, the on subsequent internal power is reset in response to the turn on the power input to the CK terminal through the switch from the internal power supply, pre-Symbol first Outputs a logic state signal.
By the signal output in the first logic state, an operator or the like notices that the changeover switch is not set to the external power supply when the external power supply is required, or that the plug of the AC adapter is not inserted into the jack. Immediately, normal settings can be made.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to embodiments. Hereinafter, as an embodiment, a case will be described in which an optional device is connected to a multifunction peripheral as a main device.
[0011]
FIG. 1 is a block diagram showing a configuration of a facsimile machine (multi-function machine) 18 having a multi-function which is a main body apparatus according to an embodiment of the present invention. The facsimile machine 18 includes an NCU 1, a MODEM 2, an image memory 3, a RAM 4, a flash memory (ROM) 5, an MPU 6, a display unit 7, an operation unit 8, a scanner (reading unit) 9, a printer. 10, CODEC 11, option I / F 12 , power supply circuit 13, and bus 14.
[0012]
The NCU 1 has a function for controlling connection with the telephone line 15 and detecting transmission and reception of the telephone number (corresponding dial signal) of the other party. MODEM2 is an ITU-T recommendation T.30. 30 based on the facsimile transmission control procedure according to 17, V. 27ter, V.I. The transmission data is modulated and the received data is demodulated in accordance with 29. The MODEM 2 also has a V23 demodulation function for receiving number display information. The image memory 3 temporarily stores received image data and document image data read by the scanner 9. The RAM 4 stores and registers FAX transfer ON and fax-email transfer ON.
[0013]
The MPU 6 is composed of a CPU, and controls each part of the facsimile apparatus according to a program stored in the flash memory 5. The display unit 7 displays various information such as the operating state of the facsimile apparatus. The operation unit 8 includes a numeric keypad, a start key, and other keys. A key for setting FAX transfer ON and FAX-email transfer ON is also provided. The scanner 9 reads image data on a document and outputs black and white binary image data. The printer 10 is an electrophotographic printer, and records received image data and image data of a document read by the scanner 9 in a copying operation on a recording sheet. The option I / F 12 connects an external option device via this.
[0014]
FIG. 2 is a block diagram showing a circuit configuration of the optional (attached) device 20 of this embodiment. The option device 20 includes an MPU 21, a flash memory 22, a RAM 23, a DPRAM 24, a LAN I / F 25, an option I / F 26, and a power supply determination circuit 27. The power determination circuit 27 is supplied with a power supply voltage from the apparatus body 18 and is connected to an AC adapter 28 for supplying external power.
[0015]
As shown in FIG. 3, the power source determination circuit 27 includes a selector switch 31 that switches between an internal power source from the main body device 18 and an external power source from the AC adapter 28, and the main body is connected to a switching terminal 31 _A of the selector switch 31. the internal power supply V _cc from the power supply circuit 13 of the apparatus (a) is connected, the shaft pin 32a of the jack 32 is connected to the switching terminal 31 _B. The contact terminal 32b of the jack 32 is grounded. Further, the common terminal 31c and the switching terminal 31 _B between the diode 33 is connected in the changeover switch 31, it and the switching terminal 31 _A of the changeover switch 31, 31c when is閉結Vcc to (B) flows into the Vcc Is preventing. A resistor 34 is connected between the shaft terminal 32a of the jack 32 and the contact terminal 32c. Although not shown, the D-type flip-flop 36 uses Vcc (B) as a power source.
[0016]
The common terminal 31 c of the changeover switch 31 is connected to the CK terminal of the D-type flip-flop 36 through the buffer 35. The contact terminal 32c of the jack 32 is connected to the clear (CLR) terminal of the D-type flip-flop 36, and the D terminal is grounded. Further, the V _cc (B) voltage from the shaft terminal 32 a of the jack 32 is applied to the preset (PR) terminal of the D-type flip-flop 36 through the delay element 37. The output terminal Q of the D-type flip-flop 36 is connected to the input port of the option MPU 21.
[0017]
If to be used internal power supply in this option device 20, the changeover switch 31 of the power supply determination circuit 27 is turned to the switching terminal 31 _A side, the internal power supply V _cc from the power supply circuit 13 of the main unit (A) Is selected and the power supply voltage V _cc is supplied to each circuit portion of the option device 20 through the common terminal 31c. When using the internal power supply, since the plug jack 3 2 to the AC adapter 28 is not inserted, the contact terminal 32c of the jack 32 is in contact with the contact piece terminal 32b, the contact terminal 32c of the jack 32 is grounded Yes. Therefore, the CLR terminal of the D flip-flop 36 receives a clear signal from the contact terminal 32c , and the Q terminal of the D flip-flop 36 remains “L”. Further, when to be used internal power supply, when the changeover switch 31 is turned to the switching terminal 31 _B-side, the plug of the AC adapter 28 to the jack 32 is not inserted, in this case, the power supply to the option device Is not supplied. For this reason, determination itself cannot be performed.
Next, the case where an external power supply should be used in the optional device 20 will be described. First, assume that the changeover switch 31 is closed on the changeover terminal 31A side, that is, the changeover switch 31 is selected on the power supply side of the main unit 18.
The operator inserts the plug of the AC adapter 28 into the jack 32 before the main body is turned on. By inserting the plug of the AC adapter 28, the external power source V _cc (B) is applied to the PR terminal of the D-type flip-flop 36 through the delay element 37, and the D-type flip-flop 36 is preset. Is output. After this, the power of the main unit 18 is turned on, the changeover switch 31 is閉結to the switching terminal 31 _A side, even if the plug of the AC adapter 28 to the jack 32 is being inserted, the optional equipment, this At the time, the internal power supply V _cc (A) of the main unit 18 is supplied. In the power ON of from the main unit 18, V _cc (A) is the switching terminal 31 _A of the changeover switch 31, via a common terminal 31c, is input to the CK terminal of the D-type flip-flop 36, the input of the D terminal at the rise Since the (ground potential) is read, the Q terminal outputs “L”. This Q = “L” indicates that the connection of the external power supply is not normal although the option connected to the main unit 18 is fully equipped. By notifying the MPU 6 via the MPU 21, the DRAM 24, and the option I / F 12 to this effect, when the external power source is to be used, it is confirmed that the external power source is not properly supplied and is not being used. An operator can be notified by displaying on the display unit 7 or the like.
[0018]
When an external power supply is used , after the plug of the AC adapter 28 is connected to the jack 32, the changeover switch 31 is closed to the changeover terminal 31B side, that is, the changeover switch 31 is selected to the external power supply side. When the power of the main unit 18 is turned on in the connected state, the external power from the AC adapter 28 is connected to the shaft terminal 32a of the jack 32, the switching terminal 31 _B of the changeover switch 31, and the common terminal 31c when the external power supply is connected. Then, the signal is input to the CK terminal of the D-type flip-flop 36. The CK terminal, the CLR terminal, and the power supply voltage Vcc (B) rise at the same time as the plug of the AC adapter 28 is connected, but V _cc (B) passes through the delay element 37 to the PR terminal of the D-type flip-flop 36. Added. During the period until the PR terminal becomes “H”, the D-type flip-flop 36 is preset and the Q terminal becomes “H” (see the waveform in FIG. 4). This Q = “H” indicates that the option connected to the main unit 18 is fully equipped and the connection (selection) of the external power source by the changeover switch is normal. In this embodiment, the abnormality is displayed on the display unit 7 of the main body device 18 only when an abnormality occurs. However, it can be configured to display the abnormality even when it is normal.
[0019]
According to this invention, when the changeover switch is turned on to the internal power supply side and no external power supply is connected, and when the changeover switch is turned on to the internal power supply side and the external power supply is connected, The changeover switch is turned on to the external power supply side, and the case where the external power supply is connected is distinguished and stored in the D-type flip-flop, and a logic signal indicating whether there is an abnormality in the power supply connection from this D-type flip-flop. If an external power supply is required depending on the number and combination of options, but the power switch is set to the internal power supply from the main unit instead of the external power supply, the external power supply If not connected, it is possible to display an abnormality on the display unit of the main device, and notifies the deficiencies of setting the serviceman, the switching of the connections and switches of the external power supply Indeed to perform, it is possible to prevent an optional operation failure due to the voltage drop.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a main unit to which an optional device according to an embodiment of the present invention is connected.
FIG. 2 is a diagram showing a configuration of an optional device connected to the main device.
FIG. 3 is a circuit diagram showing a specific circuit of a power supply determination circuit of the option device.
FIG. 4 is a waveform diagram of each part for explaining determination processing of the power supply determination circuit;
[Explanation of symbols]
18 Main unit 20 Optional device 21 MPU of optional device
26 Option I / F of optional equipment
27 Power supply determination circuit 28 AC adapter 31 selector switch 32 jack 36 D-type flip-flop 37 delay element

Claims (1)

An internal power supply from the device body to be installed;
A jack that has a shaft terminal, a contact piece terminal, a contact terminal, and receives power supply from outside by receiving insertion of a plug of an AC adapter;
A selector switch that selectively outputs one of an internal power source from the apparatus main body and an external power source from the AC adapter by switching;
A contact terminal of the jack is connected to a CLR terminal, an output voltage from the changeover switch is received by a CK terminal, a D terminal is connected to a reference potential, and a power supply voltage from the apparatus main body output from the changeover switch or the A D-type flip-flop that receives an external power supply voltage from a jack at a PR terminal via a delay element;
When the changeover switch is turned on to the internal power supply side of the apparatus main body and the plug of the AC adapter is not inserted into the jack, a signal from the contact terminal of the jack is input to the CLR terminal. The D-type flip-flop is thereby reset and outputs a first logic state signal indicating that the external power supply is not normal,
Said changeover switch has been turned to the internal power source side of the device the body, and when the plug of the AC adapter is inserted into the jack, said external power supply voltage via the delay element from the shaft pin of the jack The D-type flip-flop is preset by being applied to the PR terminal, and when the internal power supply is turned on thereafter, in response to the on-power supply input from the internal power supply to the CK terminal via the changeover switch, the D-type flip-flop A flip-flop is reset to output the signal of the first logic state;
Applied to the PR terminal the change-over switch are turned to the external power supply side, and when the plug of the AC adapter is inserted into the jack, said external power supply voltage via the delay element from the shaft pin of the jack Before the external power supply voltage is input to the CK terminal through the change-over switch, the D-type flip-flop is set to indicate that the external power supply is normal. An electronic device accessory device characterized in that the above-mentioned signal is output.

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