JP2944324B2 - Cordless telephone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cordless telephone, and more particularly to a cordless telephone having an improved method of charging a slave unit.

[0002]

2. Description of the Related Art A conventional cordless telephone has a structure as shown in a block diagram of FIG. 4 (child device) and FIG. 5 (master device). An outline of the conventional cordless telephone will be described with reference to block diagrams of FIGS. 4 and 5 and flowcharts of FIGS.

First, transmission is performed as follows. When the caller performs a call operation on the handset that is not charging on the handset side (FIG. 4) (a7), the call data is modulated into a high-frequency signal by the TXOSC section, then amplified by the TXAMP section, and transmitted from the ANT section. Sent to master unit. On the other hand, on the parent device side (FIG. 5), the ANT section receives the transmission data from the child device and performs RXAMP.
And amplifies the amplified signal in the MIX section.
The signal is mixed with the signal generated in the section C and converted into an intermediate frequency signal. Then, after amplifying the converted signal again in the IFAMP section,
The signal is detected and taken out by the DET unit, converted into 4-wire to 2-wire by a hybrid transformer, and transmitted to a public line.

[0004] On the other hand, receiving is performed as follows. Master unit receives signal from public line with hybrid transformer 2
Line-to-line conversion, which is modulated by the TXOSC unit,
After amplification in the MP unit, the signal is transmitted from the ANT unit to the slave unit.
The slave detects the transmission signal through the same circuit as the master, amplifies the signal by SPAMP, and converts the signal into sound by SP. Note that, when the call termination operation is performed on the child device side, the child device transmits the call termination data to the parent device, and then ends the call mode (a
9, a10), after receiving the termination data from the child device,
The call mode ends (b8, b9).

[0005] By the way, as a power source for the above operation, a commercial power source is used in the master unit, and a charging power source for the secondary battery is used in the slave unit. Then, the charging operation of the secondary battery is performed by placing the child device on the parent device charging section. After the end of the call mode, when the child device is placed on the parent device charging portion and charging is started. Starting from the operation, the slave unit transmits data indicating that the communication ID code can be updated to the master unit for a certain period of time (a3). When the master unit receives this data within a predetermined time after the start of charging (b3), it transmits communication ID code update data to the slave unit (b4). When the slave unit receives the update data from the master unit within a predetermined period (a4) from the data transmission indicating that the ID code can be updated (a11),
The ID code of the slave unit is updated, and the data transmission indicating that the ID code can be updated is stopped (a12).
With the above procedure, the procedure for updating the communication ID code between the parent device and the child device is completed.

On the other hand, when the predetermined time has elapsed in step a4 in FIG. 6, the data transmission indicating that the ID code can be updated is stopped (a5), and in step b2 in FIG. If it has passed, the ID from the slave unit
B1 without receiving data indicating that the code can be updated
Go back. It should be noted that the communication ID code is a code for identifying whether or not both units have a parent-child relationship (pair relationship) when transmitting and receiving between the slave unit and the master unit. In order to prevent this, updating (changing) is performed at any time within a certain range by the predetermined procedure between the parent device and the child device. Then, the updated new ID code is added to the call data at the time of subsequent transmission / reception, and is transmitted. For example, the master unit is added to the transmission data from the slave unit. The updated ID code is used to identify the call data transmitted from the slave unit.

[0007] Charging of the slave unit is started when the charging terminals provided on the master unit charging unit and the slave unit come into contact with each other.
This is the starting point of transmission / reception of D-code updateable data (a2, b2). It should be noted that whether or not the slave unit is charging
For example, a child device is detected by its charging terminal voltage, and a parent device is detected by the presence or absence of energization of its charging unit. However, the charging means and the charging detection method are not limited to these.

The configuration and operation of the conventional cordless telephone are as described above. This conventional cordless telephone properly exhibits its function in a normal use situation, and there is no particular inconvenience.

[0009]

However, when the slave unit is used continuously for a long period of time, there are the following problems. That is, a secondary battery, which is a power source for a slave unit of a conventional cordless telephone, generally has a capacity of 0.1 to prevent battery deterioration.
Charging was performed with a relatively small charging current of 1C (C: representing the nominal capacity mAH of the battery). Therefore, if the slave unit is used continuously for a long time until the secondary battery is completely discharged, the slave unit cannot operate due to a decrease in the battery voltage. When the charging is started by placing the battery (a1, a2), the transmission operation of the ID code renewable data is started according to the flowchart of FIG. However, due to the start of transmission, mainly T
Since a large amount of current is consumed in XAMP and the charging current of the base unit charging unit cannot cover the current, the current is also supplied to the TXAMP from the secondary battery being charged. As a result, the terminal voltage of the secondary battery is reduced by the control unit and the like. Drive voltage. Therefore, the slave unit cannot operate again. However, when the child device cannot operate, the power consumption is reduced, so that the charging of the secondary battery proceeds again, and the battery voltage starts to increase. Therefore, the slave unit starts transmitting the ID code renewable data again, and eventually repeats the same ID code updating operation as described above.
As a result, the charging of the secondary battery of the slave unit is not completed forever, and the communication ID code cannot be updated. Therefore, there is a problem that the telephone cannot be used forever.

The present invention prevents such a situation from occurring,
Even when the slave unit is used continuously for a long time until the secondary battery is completely discharged, the battery can be charged by the base unit charging unit, and the function of the telephone can be quickly restored. It aims to provide a cordless telephone.

[0011]

To achieve the above object, according to the present invention, there is provided a charge detecting unit for detecting that a child unit is mounted on a charging unit of a parent unit, and a parent unit and a child unit. A transmission unit for transmitting data to the master unit at the start of charging is provided in the slave unit to enable updating of the communication ID code between the slave units, and detects that the slave unit is mounted on the charging unit of the master unit. A charging detection unit, a charging unit capable of selectively supplying the first charging current and the second charging current to the slave unit, and a communication ID after detecting that the slave unit is mounted on the charging unit of the master unit. A control unit that controls the charging unit to supply the first charging current during the time when the code is completed to register and then switch to the second charging current smaller than the first charging current, is provided in the base unit, It is characterized by the following.

According to a second aspect of the present invention, in the cordless telephone according to the first aspect, the control unit provided in the master unit completely discharges after detecting that the slave unit is put on the charging unit of the master unit. That the time for supplying the first charging current is controlled up to the sum of the charging time until the secondary battery of the machine becomes operable and the predetermined time required for registering the communication ID code. Features.

[0013]

In the above configuration, the parts other than the charging unit and the control unit of the master unit and the configuration of the slave unit are the same as those of the above-mentioned prior art. The operation based on the configuration of the charging unit and the control unit of the master unit will be described. The present invention provides a charging unit that can selectively supply a first charging current and a second charging current to a child device, and a communication ID code after detecting that the child device is placed on the charging unit of the parent device. There is a feature that a control unit that can be switched to the first charging current until the registration is completed and then switch to the second charging current is provided in the master unit. The charging current can be supplied to the secondary battery, and the update of the ID code can be completed.

That is, when the slave unit is placed on the master unit charging unit to charge the slave side secondary battery, charging is started with this as a trigger, but it is necessary to charge the battery for a certain period from the start of charging. And a current (first charging current) that is equal to or more than or equal to the sum of the current required for the ID code update procedure operation and the current that is more suitable as the battery charging current after a predetermined period has elapsed. (Second charging current; a current smaller than the first charging current) so as to always supply a necessary and sufficient current and reduce battery deterioration. With this configuration, for a certain period after the start of charging, a larger first charging current is supplied from the charging unit, thereby charging the slave unit-side secondary battery while charging the slave unit-side secondary battery. And the driving current for updating the communication ID code that is activated by the communication. Therefore, a current shortage does not occur in the charging unit, and stagnation of the child device function due to a voltage drop can be avoided.

[0015] When the first charging current is no longer required after a lapse of a predetermined period from the start of charging, the control unit switches the current of the charging unit to a second charging current smaller than the first charging current. Can be charged with an appropriate charging current. It should be noted that, for some reason, the update of the ID code may not be determined to have been completed even after a certain period of time. However, in that case, supplying the first charging current forever will adversely affect the battery life. For this reason, in the present invention, the time for flowing the first charging current is the charging time until the secondary battery of the slave unit which has been completely discharged after detecting that the slave unit is placed on the charging unit of the master unit becomes operable. And a predetermined time required for registering the communication ID code is controlled as a limit.

[0016]

FIG. 1 is a schematic block diagram of a cordless telephone (parent device) of the present invention, and FIG. 2 is a flowchart showing the operation thereof. An embodiment of the present invention will be described based on these drawings. Note that the overall configuration and operation of the child device and the configuration and operation of parts other than the control unit and the charging unit of the parent device are the same as those of the above-described conventional technology, and thus description thereof is omitted.

The charging section of the master unit is configured to selectively supply two types of charging currents. One of the two types of charging current (first charging current) is set to, for example, 0.2 C, and the other (second charging current) is set to 0.1 C. Note that such a charging unit that selectively supplies two types of charging currents is generally well known. The control unit performs the control operation shown in FIG. Of these operations, the operation during non-charging is not different from the operation of the conventional parent device, and the operation during charging is different from the conventional operation. That is, first, when the user places the slave unit on the charging terminal, the control unit detects the start of charging (C1), and determines in step C2 whether a predetermined time has elapsed from the start of charging. The predetermined time here is, as shown in FIG. 3, the sum (tb + t) of the charging time tb until the fully discharged secondary battery becomes operable and the time tr required to register the communication ID code.
r). The time tr required for registering the communication ID code is defined as the time when the slave starts transmitting the ID code renewable data, the master transmits the ID code update data to the slave, and the slave receives the ID. The time it takes to complete the code update data.

In step C2, if the predetermined time has not elapsed yet, the ID code renewable data has not been sent from the slave unit (C3), and the data has been sent from the slave unit to the master unit. When the timer (not shown) set at the expected time has not expired (C
4), a process of supplying the first charging current from the charging unit to the slave unit is performed (C5). Since this process is performed after step C3, the slave unit transmits ID code renewable data to the master unit after charging of the secondary battery with a current of 0.2 C is started. (See a3 in FIG. 6).
Therefore, even when the secondary battery is almost discharged, the TXAMP of the slave unit is driven by a part of the charging current supplied from the charging unit of the master unit to transmit the ID code renewable data. Can be made.

In step C2, if a predetermined time has elapsed from the start of charging, the second charging current is supplied immediately. On the other hand, if the predetermined time has not yet elapsed and the ID code updateable data is sent from the slave unit (C3), the ID code update data is sent from the master unit to the slave unit. The ID code is transmitted and the ID code is updated. Subsequently, the first charging current is switched to the second charging current, and charging of the secondary battery is continued at an appropriate current value (0.1 C) that does not adversely affect the battery life (C
7).

[0020]

According to the present invention as described above,
Even when the secondary unit is used for a long time and the secondary battery, which is the power supply of the secondary unit, is discharged to near full discharge, charging proceeds promptly when it is placed on the main unit charging section. Then, a predetermined operation to be performed by the slave unit during charging is enabled. Therefore, unlike the conventional cordless telephone, it is possible to prevent a phenomenon that the handset function becomes inoperable due to the complete discharge of the secondary battery, and it is possible to quickly return the telephone to a usable state. To play.

Further, according to the present invention, a necessary and sufficient charging current is supplied at the beginning of battery charging, and after the predetermined operation of the slave unit becomes possible, the second charging current is appropriately reduced to a smaller value. As a result, the life of the secondary battery is not impaired by excessively large current charging.

[Brief description of the drawings]

FIG. 1 is a block diagram of a cordless telephone (parent device) of the present invention.

FIG. 2 is a flowchart showing an operation of the cordless telephone (parent device) of the present invention.

FIG. 3 is a diagram showing a predetermined time in a flowchart (FIG. 2) of the cordless telephone (parent device) of the present invention.

FIG. 4 is a block diagram of a cordless telephone (child device).

FIG. 5 is a block diagram of a conventional cordless telephone (parent device).

FIG. 6 is a flowchart showing an operation of the cordless telephone (child device).

FIG. 7 is a flowchart showing the operation of a conventional cordless telephone (parent device).

Continuation of the front page (56) References JP-A-3-2744831 (JP, A) JP-A-63-120539 (JP, A) JP-A-2-37849 (JP, A) JP-A-1-241929 (JP) , A) JP-A-62-26937 (JP, A) JP-A-2-53648 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04B 7/24-7/26 H04M 1/00 H04Q 7/00-7/38

Claims (2)

(57) [Claims] A charge detection unit for detecting that a slave unit is mounted on a charge unit of the master unit, and a communication ID code between the master unit and the slave unit that can be updated. A transmission unit for transmitting data is provided in the slave unit, a charge detection unit that detects that the slave unit is mounted on the charging unit of the master unit, and a first charging current and a second charging current to the slave unit. The first charging current is supplied during a period in which the registration of the communication ID code is completed after detecting that the slave unit is mounted on the charging unit of the master unit and the charging unit that can selectively supply the first charging current. And a control unit for controlling the charging unit so as to switch to a second charging current smaller than the one charging current. 2. A control unit provided in the master unit, after detecting that the slave unit is put on the charging unit of the master unit, a charging time until the secondary battery of the slave unit that has been completely discharged becomes operable. 2. The cordless telephone according to claim 1, wherein a time for supplying the first charging current is controlled up to a time obtained by adding a predetermined time required for registering the communication ID code. 3.