Cordless telephone apparatus

• US 5,805,998 A
• Filed: 07/05/1995
• Issued: 09/08/1998
• Est. Priority Date: 07/20/1994
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Kodama, Yoshisuke
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): Ferguson, Keith
• Application Number:
  US08/498,479
• Time in Patent Office: 1,161 Days
• Field of Search: 379/61, 455/38.3, 455/127, 455/343, 455/462, 455/572, 455/573, 455/575, 455/574, 455/569, 455/561, 320/13, 320/14, 320/2
• US Class Current: 455/462
• CPC Class Codes: H04M 1/72502 with one base station connected to a single line
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A cordless telephone apparatus includes a radio transceiver for cordless communication with a slave unit. A controller is operative for controlling the radio transceiver. A main power supply is operative for generating electric power from commercial ac power. An auxiliary battery is operative for generating electric power. The radio transceiver and the controller are activated by either the electric power generated by the main power supply or the electric power generated by the auxiliary battery. A voice amplifier connected between an external telephone line and the radio transceiver is operative for amplifying a speech signal transmitted between the external telephone line and the radio transceiver. The voice amplifier is activated by electric power fed from the external telephone line.

Claims

1. A cordless telephone apparatus for communication with a slave unit, comprising:

a radio transceiver for cordless communication with the slave unit;

a controller for controlling the radio transceiver;

a main power supply for generating electric power from commercial ac power;

an auxiliary battery for generating electric power;

means for activating the radio transceiver and the controller by either the electric power generated by the main power supply or the electric power generated by the auxiliary battery;

a voice amplifier connected between an external telephone line and the radio transceiver for amplifying a speech signal transmitted between the external telephone line and the radio transceiver;

means for activating the voice amplifier by electric power fed from the external telephone line; and

monitoring means for detecting whether or not a voltage across the auxiliary battery drops below a given voltage, and for suspending the activation of the radio transceiver and the controller by the auxiliary battery to prevent over-discharge of the auxiliary battery when the voltage across the auxiliary battery drops below the given voltage.

2. The cordless telephone apparatus of claim 1, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, the predetermined reference level being higher than the given voltage, and means for informing the slave unit of a voltage drop when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

3. The cordless telephone apparatus of claim 1, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a redetermined reference level, an indicator provided in the slave unit, and means for activating the indicator when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

4. A cordless telephone apparatus comprising:

a master unit; and

a slave unit;

wherein the master unit comprises a radio transceiver for cordless communication with the slave unit;

a controller for controlling the radio transceiver;

a main power supply for generating electric power from commercial ac power;

an auxiliary battery for generating electric power;

means for activating the radio transceiver and the controller by either the electric power generated by the main power supply or the electric power generated by the auxiliary battery;

a voice amplifier connected between an external telephone line and the radio transceiver for amplifying a speech signal transmitted between the external telephone line and the radio transceiver;

means for activating the voice amplifier by electric power fed from the external telephone lines; and

monitoring means for detecting whether or not a voltage across the auxiliary battery drops below a given voltage, and for suspending the activation of the radio transceiver and the controller by the auxiliary battery to prevent over-discharge of the auxiliary battery when the voltage across the auxiliary battery drops below the given voltage.

5. The cordless telephone apparatus of claim 4, wherein the monitoring means comprises means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, the predetermined reference voltage being higher than the given voltage, and means for informing the slave unit of a voltage drop when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

6. The cordless telephone apparatus of claim 4, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, an indicator provided in the slave unit, and means for activating the indicator when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

7. A cordless telephone apparatus comprising:

a master unit having a main portion and an interface portion, the interface portion being connected between an external telephone line and the main portion;

a slave unit for cordless communication with the master unit;

a main power supply for generating electric power from commercial ac power;

means for normally activating the main portion of the master unit by the electric power generated by the main power supply;

an auxiliary battery for generating electric power;

means for activating the main portion of the master unit by the electric power generated by the auxiliary battery in place of the electric power generated by the main power supply when a stoppage of the commercial ac power occurs;

a voice amplifier provided in the interface portion of the master unit for amplifying a speech signal transmitted between the external telephone line and the main portion of the master unit;

means for activating the voice amplifier by electric power fed from the external telephone line; and

monitoring means for detecting whether or not a voltage across the auxiliary battery drops below a given voltage, and for suspending the activation of the main portion of the master unit by the auxiliary battery to prevent over-discharge of the auxiliary battery when the voltage across the auxiliary battery drops below the given voltage.

8. The cordless telephone apparatus of claim 7, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, and means for informing the slave unit of a voltage drop when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

9. The cordless telephone apparatus of claim 7, wherein the monitoring means comprises means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, an indicator provided in the slave unit, and means for activating the indicator when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

10. A cordless telephone apparatus comprising:

a master unit having a main portion, an interface portion connected between an external telephone line and the main portion, and means for isolating the main portion and the external telephone line from each other with respect to a direct current;

a slave unit for cordless communication with the master unit;

a main power supply for generating electric power from commercial ac power;

means for normally activating the main portion of the master unit by the electric power generated by the main power supply;

an auxiliary battery for generating electric power;

means for activating the main portion of the master unit by the electric power generated by the auxiliary battery in place of the electric power generated by the main power supply when a stoppage of the commercial ac power occurs;

a voice amplifier provided in the interface portion of the master unit at a location between the external telephone line and the isolating means for sampling a speech signal transmitted between the external telephone line and the main portion of the master unit;

means for activating the voice amplifier by electric power fed from the external telephone line; and

monitoring means for detecting whether or not a voltage across the auxiliary battery drops below a given voltage, and for suspending the activation of the main portion of the master unit by the auxiliary battery to prevent over-discharge of the auxiliary battery when the voltage across the auxiliary battery drops below the given voltage.

11. The cordless telephone apparatus of claim 10, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, and means for informing the slave unit of a voltage drop when the detected voltage across the auxiliary battery is lower than the predetermined reference level.

12. The cordless telephone apparatus of claim 11, wherein the monitoring means includes means for detecting the voltage across the auxiliary battery, means for deciding whether or not the detected voltage across the auxiliary battery is lower than a predetermined reference level, an indicator provided in the slave unit, and means for activating the indicator when the detected voltage across the auxiliary battery is lower than the predetermined reference level.