JPH0629903A - Charger for cordless telephone slave set - Google Patents

Abstract

PURPOSE:To implement alarm display indicating time management up to fill charging and necessity of charging surely and easily. CONSTITUTION:A mode management means 1 manages the operating state of a cordless telephone slave set and uses a constant current circuit 2 whose constant current for charging is selected from plural currents set in response to the charging state of a charging battery 4 and the mode of the cordless telephone slave set. A constant current changeover means 3 receives an output of the mode management means 1 to generate a changeover signal of the constant current of the constant current circuit 2. A charging state of the battery 4 is obtained based on the constant current from the constant current circuit 2 and the charging time by a charging quantity arithmetic means 5. A power consumption arithmetic means 6 receives an output of the mode management means 1 to obtain the battery power consumption based on the current consumption in response to the operating state and the operating time. A required charge quantity arithmetic means 7 operates the required charging quantity of the battery 4 based on the obtained charging quantity and consumed quantity. The required charging time is managed based on the obtained required charging quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for a cordless telephone handset.

[0002]

2. Description of the Related Art There is known a cordless telephone device including a telephone main unit connected to a telephone line and a cordless telephone slave unit wirelessly connected to the telephone main unit.

In this cordless telephone device, the cordless telephone slave unit is battery-operated because it is used independently. A nickel-cadmium battery is generally used as a battery, and charging is performed by a dedicated charger.

There are voltage control charging method, ΔV control charging method, V taper control method, etc. as the charging method of the nickel cadmium battery. However, the ΔV control charging method and the V taper control method have problems of circuit accuracy, cost, etc. Not often used in cordless telephone devices, the voltage controlled charging method is generally used.

The voltage-controlled charging system monitors the voltage of the battery being charged, and when the voltage reaches a preset voltage indicating full charge, it switches to trickle charging to prevent overcharging. It has the advantage of being simple.

[0006]

The voltage-controlled charging method has the advantage that the circuit configuration is simple as described above, but has the drawback that the voltage value indicating full charge fluctuates due to temperature changes or charging current values. is there. Therefore, it is difficult to obtain the stability of charging.

Further, the conventional charging device monitors the terminal voltage of the rechargeable battery and issues an alarm to notify the necessity of quick charging when the voltage falls below a predetermined value, so that the remaining charge of the battery is always maintained. Because it is not something to monitor, with the battery at that time,
It was not possible to accurately display the available call time, which is how long the call is available.

[0008]

In order to solve the above problems, a cordless telephone handset according to the present invention has a structure as shown in FIG.
As shown in, the mode management means 1 for managing the operating state of the cordless telephone slave unit and the constant current value for charging can be switched to a plurality of values set according to the mode of the cordless telephone slave unit. Constant current circuit 2 and mode management means 1
Constant current switching means 3 for generating a switching signal SW for the constant current value of the constant current circuit 2, and the constant current from the constant current circuit 2 and the charging time, the battery 4 of the cordless telephone slave unit.
A charge amount calculation means 5 for obtaining the charge amount of the cordless handset, and a consumption amount calculation means 6 for receiving the output of the mode management means 1 and obtaining the battery consumption amount from the current consumption and the operating time according to the operating state of the cordless telephone slave unit, It has a required charge amount calculation means 7 for calculating the required charge amount of the battery 4 based on the charge amount from the charge amount calculation means 5 and the battery consumption amount from the consumption amount calculation means 6.

The mode management means 1 is supplied with the detection output of the detection means 8 for detecting the connection state of the cordless telephone slave unit to the charger, and the power switch on / off of the cordless telephone slave unit and its function. An output corresponding to the switch input of the switch group 9 such as a button switch is supplied.

Further, a callable time calculating means 10 for receiving the required charge amount from the required charge amount calculation means 7 and calculating the callable time by the cordless telephone slave unit based on the required charge amount, and this callable time calculation Display means 11 for receiving the output of the means 10 and displaying the callable time of the cordless telephone handset
Equipped with.

[0011]

According to the present invention having the above-described structure, when the detecting means 8 detects that the cordless telephone handset is connected to the charger, the mode managing means 1 determines that the charging mode is set, and When it is detected that the cordless telephone handset is not connected to the charger, the mode management means 1 determines that it is the use mode. Then, according to the switch input of the switch group 9, the mode management means 1 determines the operating state of the cordless telephone slave unit in the charging mode and the use mode.

The charging current supplied from the constant current circuit 2 to the battery is a constant current, but there are a plurality of constant current values preset according to the operation mode of the cordless telephone handset and the charging state of the battery 4. It can be switched.

The constant current switching means 3 creates an output for selecting a constant current value according to the operation mode based on the output from the mode management means 1 indicating the operation state of the cordless telephone handset, and outputs the output. It is supplied to the current circuit 2 to switch the constant current value.

In the case of the example of FIG. 1, the charge amount calculation means 5 receives the selective output of the constant current value from the constant current switching means 3 to know the constant current value of charging, and the same of the selected outputs. The charge time based on the constant current value is known as the state time, and the charge amount is calculated as (constant current value) x (charge time) = (charge amount). It is also possible to detect the constant current value from the constant current circuit 2 and calculate the charge amount as the product of this and the connection time of the constant current value.

The calculated charge amount is the required charge amount calculation means 7
And is subtracted from the required charging amount up to that point.

When the battery is in a fully charged state (required charge amount is zero), the output of the required charge amount calculation means 7 causes the constant current switching circuit 3 to select a constant current value during trickle charging. As a result, the battery becomes trickle charged and overcharging is prevented.

In the use mode in which the cordless telephone slave unit is detached from the charger, the consumption amount calculating means 6 responds to the signal indicating the operating state of the cordless telephone slave unit identified by the mode managing means 1, The consumption amount is calculated and summed as (consumption amount) = (current consumption according to operating state) × (duration of the operating state).

Then, this consumption amount is supplied to the required charge amount calculation means 7 and added to the required charge amount. When the required charge amount exceeds a certain value, an alarm may be issued and the constant current value for charging may be forcibly selected as the constant current value for quick charging.

In this way, the amount of charge and the amount of consumption are monitored,
Since the required amount of charge is always managed, the charge time until full charge can be managed reliably and accurately.

In this case, further, from the information on the required charge amount from the required charge amount calculation means 7, in the callable time calculation means 10, for example, (the usable capacity of the battery) = (when the rapid charge is required, The usable capacity of the battery is calculated as (required charge amount)-(obtained required charge amount), and the callable time is calculated as (usable capacity / current consumption during call) = (callable time). Then, the callable time is displayed on the display means 11. The display method may be a method of displaying time numerically, or may be a bar graph-like display using a plurality of light emitting diodes.

Since the callable time is displayed in this way,
The user can make a continuous call with peace of mind during that time. Also, if the callable time is short, it is understood that the battery needs to be charged, and it also serves as a charge warning display.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a charging device for a cordless telephone handset according to the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram of an embodiment of the present invention, which is an example in which a microcomputer (hereinafter referred to as CPU) is used for control. In FIG. 2, 20 is a charger, 21 is an AC adapter, and 30 is a cordless telephone handset.

The charger 20 has a protection circuit 23 and a smoothing capacitor 24, and is connected to a commercial AC power source via an AC adapter 21. 25 and 26 are connection terminals for connecting the charger 20 and the cordless telephone subunit 30. In the cordless telephone subunit 30, reference numeral 31 denotes a wireless circuit unit for exchanging call voice and data with a telephone main unit (not shown) via a wireless channel.

Reference numeral 32 denotes a control circuit section which controls the radio circuit section 31 and other controls of the slave unit 30. A CPU 33 controls the operation of the child device 30 according to a program. Reference numeral 34 is a keyboard such as a function button, and 35 is a power on / off switch, and an output indicating each operation state is supplied to the CPU 33. 36
Is a liquid crystal display as an example of display means, which includes dial number, time, and operating state of the handset (extension call,
In addition to displaying external line calls, holding calls, receiving calls, etc., the available time of calls, a warning of the necessity of battery charging, etc. are displayed.

Reference numeral 37 is a rechargeable battery such as a nickel-cadmium battery. Reference numeral 38 is a constant current circuit that supplies a constant current as a charging current to the battery 37. This constant current circuit 38 is a CPU
The constant current value can be changed by the control signal from 33. The constant current value is preset in a plurality of ways according to the operating state of the child device 30 and the charging state of the battery 37 as described later.

Reference numeral 39 is a charging current detection circuit. When the cordless handset 30 is connected to the charger 20 at the connection terminals 25 and 26, the battery 37
Since the charging current flows through the charging current detecting circuit 39, the charging current detecting circuit 39 detects the charging current and supplies the CPU 33 with a signal indicating that the slave unit 30 is connected to the charger 20 and is being charged.

The constant current value of the constant current circuit 38 described above is set as follows. (1) In case of rapid charging (1) -a Power switch is off, slave unit is not operating (quick charging current) + (quiescent circuit current) = (constant current value A) (1) -b Standby Rapid charging while performing intermittent reception (quick charging current) + (intermittent reception circuit current) = (constant current value B) Here, standby intermittent reception refers to the non-operation state and whether or not there is received data. This is an operation mode in which the intermittent reception state in which the wireless circuit unit 31 is operated to detect the is alternately performed every minute time. The charging current in the non-operating state of intermittent reception during the rapid charging is equal to the constant current value A. (2) In the case of steady charging that is not quick charging (2) -a Intermittent reception non-operation state (charging current during intermittent reception) + (quiescent circuit current) = (constant current value C) (2) -b Intermittent During intermittent reception (charging current during intermittent reception) + (circuit current during intermittent reception) =
(Constant current value D) (3) In the case of trickle charge after full charge (3) -a Intermittent reception non-operation state (trickle charge current) + (quiescent circuit current) = (constant current value E) (3) -b Intermittent reception Intermittent reception (trickle charge current) + (intermittent reception circuit current) = (constant current value F) (4) Incoming call (trickle charge current) + (incoming circuit current) = ( Constant current value G) The constant current value can be reduced or increased depending on the charging time and the circuit current condition.

The CPU 33 discriminates the above operating state and supplies a constant current switching signal to the constant current circuit 38. Then, the CPU 33 measures the time of each charge state, and calculates the charge amount as (charge constant current value) × (time) = (charge amount).

The required charge amount is set in the CPU 33. If the battery is empty, the maximum required charge will be set. When the battery is charged, the required charge amount is subtracted from the required charge amount.

When the cordless handset 30 is detached from the charger 20 and used, the battery is consumed. The modes in use include during a call, intermittent reception, incoming calls, and an operation stop state due to power off. However, since the current consumption in each mode is fixed, the CPU 33 determines the usage time in each mode. By measuring, the battery consumption is calculated as (current consumption in use mode) x (time) = (battery consumption). Then, this battery consumption amount is added to the required charge amount. At the time of this addition, a process of converting the battery consumption amount into the additional required charge amount is performed. For example, in the case of a battery having a capacity of 400 mAH, the battery will not be fully charged unless it is charged at 600 mAH.

Then, a charge loss coefficient (1.5 in the above example) is calculated as (maximum required charge amount / capacity) = (charge loss coefficient), and (battery consumption amount) × (charge loss coefficient) = (additional required charge amount) ) Is performed. Then, a process of adding the obtained additional required charge amount to the required charge amount is performed.

In this case, when the required charge amount reaches a predetermined value TH, which is slightly smaller than the maximum required charge amount, the liquid crystal display 36 displays a warning display to warn that the battery 37 is almost empty. In.

When the user connects the handset 30 to the charger 20, the CPU 33 supplies the constant current value switching signal for selecting the constant current value A or B for rapid charging from the CPU 33 to the constant current circuit 38 to force the constant current circuit 38. It is in the state of quick charge.

When the required charge amount is zero, that is, when the battery is fully charged, the constant current value switching signal from the CPU 33 selects the constant current value for trickle charging.

The CPU 33 manages the charging time while monitoring the required charging amount as described above.

Further, the CPU 33 obtains the remaining capacity from the required charging amount by the following calculation: (maximum required charging amount)-(current required charging amount) = (remaining capacity), (remaining capacity) ÷ (current consumption during call) Charge loss coefficient) = (callable time) The callable time is obtained by the following calculation. Then, the callable time is displayed on the liquid crystal display 36.

Further, a plurality of light emitting diodes are arranged in a line, and when fully charged (required charge amount is zero), all of these light emitting diodes are turned on, and when the battery is consumed, the required charge amount is reached. It is possible to visually display the exhausted state of the battery by sequentially turning off the light emitting diodes corresponding to the number from the end. This display is
It also indicates that a call can be made according to the number of light emitting diodes that are lit.

Note that the callable time may be obtained by detecting the voltage of the battery and displayed by the liquid crystal display or the plurality of light emitting diodes.

3 to 5 are flowcharts of an example of charge control in the CPU 33. The charge control operation will be further described below with reference to this flowchart.

First, it is determined whether or not the cordless handset 30 is connected to the charger 20 (step 101). As a result of this determination, if the cordless handset 30 is not connected to the charger 20, the cordless handset use mode is entered, and the routine proceeds to step 102, where it is discriminated whether the power is on or off.

If the power is on, the usage state of the child device 30 is identified (step 103). As a result of the identification, in this example, the standby state (step 104), the outgoing call, the call state (step 105),
Any of the incoming call states (step 106) are identified. Then, next, the usage time in the identified state is measured (steps 107, 108, 109). Then, when the end of the usage state is detected (steps 110, 111, 112), the battery consumption in the usage state is calculated (steps 113, 114, 115).
Next, the calculated battery consumption amount is converted into an additional required charge amount and added to the required charge amount (step 116).

If it is determined in step 102 that the power is off, the battery save mode is entered (step 117), the duration of this mode is measured (step 118), and the end of this mode is detected (step 119). ), The battery consumption in this mode is calculated (step 120), and then the routine proceeds to step 116, where the battery consumption is converted into an additional required charge and added to the required charge. After completion of step 116, the process returns to step 101. When it is determined in step 101 that the mobile device 30 is connected to the charger 20, the charging mode is set, and the process proceeds to step 121, in which it is determined whether the power is on or off. If the power is on, the state of the child device 30 is checked (step 122). If the mobile device 30 is in the standby reception state (step 123), the required charge amount at that time is checked (step 124).

As a result of the check in step 124, when the required charge amount exceeds the predetermined value TH and the charge is kept below a certain level (step 125), the charging current from the constant current circuit 38 becomes the constant current values A and B. Is set according to standby reception (step 12
6). Then, the duration of that state is measured (step
127), and the charge amount is calculated (step 128). Then, the charge amount is subtracted from the required charge amount (step 129).

If the result of the check in step 124 is that the required amount of charge is less than or equal to the predetermined value TH and the charge is greater than or equal to a certain level (step 130), the charging current waits at the constant current values C and D. (Step 131). afterwards,
After proceeding to step 127 and measuring the duration of the state, the charge amount is calculated and the calculated charge amount is subtracted from the required charge amount (steps 128 and 129). When step 129 ends, the process returns to step 101.

As a result of checking the required amount of charge in step 124, it is determined that the charging is completed and the battery is fully charged (step 13).
2), and the charging current is set to the constant current values E and F during trickle charging according to the standby reception (step 133), and the step
Return to 101.

As a result of checking the state of the handset unit 30 in step 122, if it is identified that a call is being received (step 134), the constant current value G is set (step 135), and then step 10 is performed.
Return to 1.

When it is determined in step 121 that the power is off, the process proceeds to step 136, where it is determined whether charging is completed. When it is determined that the charging is not completed, the charging current is set to the constant current value A (step 137), the duration of the state is measured (step 138), and the charge amount is calculated and obtained (step 137). 139). Then, the process proceeds to step 129, and the charge amount is subtracted from the required charge amount.

When it is determined in step 136 that the charging is completed, the routine proceeds to step 140, where the constant current value E is set, and then the routine returns to step 101.

[0050]

According to the present invention, while managing the state of the cordless telephone handset, the charged amount and consumed amount of the battery are constantly monitored and calculated, and these are subtracted from and added to the required charged amount. By doing so, it is possible to always detect the required charge amount at the present time. Therefore, time management until full charge can be performed accurately, reliably, and easily. In addition, it is possible to easily detect that the charge has dropped below a certain level from the required charge amount, and it is possible to reliably display an alarm for charging.

Further, it can be easily and surely detected that the charging has dropped below a certain level from the required charging amount, and the charging alarm can be surely displayed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a charging device for a cordless telephone handset according to the present invention.

FIG. 2 is a block diagram of an embodiment of a charging device for a cordless telephone handset according to the present invention.

FIG. 3 is a diagram showing a part of a flowchart for explaining the operation of the charging device for the cordless telephone handset according to the present invention.

FIG. 4 is a diagram showing a part of a flowchart for explaining the operation of the charging device for the cordless telephone handset according to the present invention.

FIG. 5 is a diagram showing a part of a flowchart for explaining the operation of the charging device for the cordless telephone handset according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Mode management means 2, 38 ... Constant current circuit 3 ... Constant current value switching means 4, 37 ... Rechargeable battery 5 ... Charge amount calculation means 6 ... Battery consumption amount calculation means 7 ... Necessary charge amount calculation means 11 ... Display means 36 ... Liquid crystal display

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kozo Kobayashi 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Inventor Takeo Saito 1-6-1, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (1)

[Claims] 1. A mode managing means for managing an operating state of a cordless telephone slave unit, and a constant current value for charging is set according to a mode of the cordless telephone slave unit and a charging state of a battery of the cordless telephone slave unit. A constant current circuit capable of switching to a plurality of different values, constant current switching means for receiving an output of the mode management means, and generating a constant current value switching signal of the constant current circuit, and a constant current circuit from the constant current circuit. The battery consumption of the cordless telephone handset is calculated from the constant current and the charging time, and the battery consumption is calculated from the current consumption and the operating time according to the operating state by receiving the output of the mode management means. And a required charge amount calculation unit for calculating the required charge amount of the battery based on the charge amount from the charge amount calculation unit and the consumption amount from the consumption amount calculation unit. Charging device of the cordless telephone handset which is adapted to manage the necessary charging time based on the required amount of charge.