Electronic apparatus, electronic apparatus system, and operation mode switching method

• US 7,348,759 B2
• Filed: 12/23/2003
• Issued: 03/25/2008
• Est. Priority Date: 12/27/2002
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ozeki, Akihiro
• Primary Examiner(s): Berhane; Adolf
• Assistant Examiner(s): Berhanu; Samuel
• Application Number:
  US10/743,560
• Publication Number:
  US 20040164713A1
• Time in Patent Office: 1,554 Days
• Field of Search: 320/101, 320/137, 307/46, 307/66
• US Class Current: 320/101
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

An electronic apparatus system of this invention includes an electronic apparatus, and a fuel cell unit which is detachable from the electronic apparatus. The fuel cell unit incorporates a DMFC that can produce electricity by chemical reaction. On the other hand, the electronic apparatus has at least two operation modes having different power consumption amounts such as a normal mode and power saving mode. Upon switching the operation mode, the electronic apparatus advises the fuel cell unit accordingly. Upon reception of this advice, the fuel cell unit compares the current output electric power of the DMFC with the power consumption amount in the operation mode after switching, and returns a message based on that comparison result. The electronic apparatus switches the operation mode based on the returned message.

Claims

1. A cell unit which is detachably connected to an electronic apparatus and supplies the electronic apparatus with electric power, the electronic apparatus having a plurality of operation modes having different power consumption requirements, the cell unit comprising:

a fuel cell which produces electricity by chemical reaction;

a rechargeable secondary battery;

a reception unit configured to receive a message which indicates a switch in the operation modes from the electronic apparatus; and

a response unit configured to send message to the electronic apparatus indicating that the power consumption required to operate the electronic apparatus in the newly-switched operation mode overruns the rated output of the fuel cell, but still falls within the rated output of the cell unit when;

the required power consumption to operate the electronic apparatus in the switched operation mode exceeds an electric power that is supplied from the fuel cell, and

the required power consumption amount is lower than an electric power that is supplied from both the fuel cell and the secondary battery.

2. The cell unit according to claim 1, further comprising:

a power control unit configured to control the fuel cell to lower the output electric power, when the output electric power of the fuel cell is larger than the required power consumption amount by a value beyond a predetermined value.

3. The cell unit according to claim 1, further comprising:

a power control unit configured to control the fuel cell to raise the output electric power, when the required power consumption is larger than the output electric power of the fuel cell, wherein

the response unit sends a message indicating that the output electric power of the fuel cell has been changed to the electronic apparatus, when the output electric power of the fuel cell has reached the required power consumption amount under the control of the power control unit.

4. The cell unit according to claim 1, further comprising:

a power control unit configured to charge the secondary battery by electric power as a difference between the output electric power of the fuel cell and required power consumption when the output electric power of the fuel cell is larger than the required power consumption amount by a value beyond a predetermined value.