JPH0752893B2 - Callable time display device for cordless handset - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a callable time display device for a cordless telephone handset.

2. Description of the Related Art A cordless telephone device is known which comprises 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-powered because it is used independently. A nickel-cadmium battery is generally used as a battery, and charging is performed by a dedicated charger. As the charging method for NiCd battery, voltage control charging method,
There are ΔV control charging method, V taper control method, etc.
The control charging method and the V taper control method are not often used in cordless telephone devices because of problems such as circuit accuracy and cost, and the voltage control charging method is generally used. The voltage-controlled charging method monitors the voltage of the battery during charging, and when the voltage reaches a preset voltage indicating full charge, switches to trickle charging to prevent overcharging, and the circuit configuration is simple. There is an advantage. With such a charging method, the rechargeable battery of the cordless phone handset is charged, but the remaining capacity of the rechargeable battery is reduced by the use of the cordless phone handset, and the terminal voltage of the rechargeable battery becomes a predetermined value. When the following occurs, the wireless transmission / reception circuit of the child device cannot operate normally. Therefore, conventionally, the terminal voltage of the rechargeable battery is monitored, and when the terminal voltage becomes equal to or lower than a predetermined value, an alarm display or an alarm sound is emitted to prompt charging.

[Problems to be Solved by the Invention]

However, in the case of the conventional method described above, the terminal voltage of the rechargeable battery is only monitored, and the remaining charge capacity of the battery is not constantly monitored. With the remaining capacity, I couldn't know how much time I could talk to, how much time I could talk. SUMMARY OF THE INVENTION It is an object of the present invention to provide a callable time display device for a cordless telephone handset capable of solving the above problems.

[Means for Solving the Problems]

In order to solve the above problems, a callable time display device for a cordless telephone handset according to the present invention comprises a rechargeable battery built in the cordless telephone handset and a charge amount of the rechargeable battery multiplied by a charging current and a charging time. And a means for obtaining the battery consumption of the rechargeable battery by multiplying the consumption current by the operating time, and a means for obtaining the remaining capacity of the rechargeable battery from the obtained charge and battery consumption. And a display unit for quantitatively displaying the obtained remaining capacity.

[Action]

According to the present invention having the above configuration, the charge amount is obtained from the charging current and the charging time of the rechargeable battery, and the consumption amount is obtained from the consumption current and the consumption time. It is always obtained, and based on this, the remaining capacity of the rechargeable battery is obtained and quantitatively displayed on the display means.
In this case, the remaining capacity can be directly displayed in the form of talk time.

【Example】

An embodiment of a callable time display device for a cordless telephone handset according to the present invention will be described below with reference to the drawings. FIG. 1 shows, as a functional block, a configuration of an embodiment of a callable time display device of a cordless telephone handset according to the present invention. That is, as shown in FIG. 1, the callable time display device of the cordless telephone subunit of this example has a mode managing means 1 for managing the operating state of the cordless telephone subunit, and a constant current value for charging, A constant current circuit 2 capable of switching among a plurality of values set according to the mode of the cordless telephone handset, and an output of the mode management means 1, and generates a constant current value switching signal SW of the constant current circuit 2. Charge amount calculation means 5 for obtaining the charge amount of the battery 4 of the cordless telephone handset from the constant current switching means 3 and the constant current from the constant current circuit 2 and the charging time.
And a consumption amount calculation unit 6 that receives the output of the mode management unit 1 and obtains a battery consumption amount from the consumption current and the usage time according to the operating state of the cordless telephone slave unit, and the charge amount from the charge amount calculation unit 5. And a required charge amount calculation means 7 for calculating the required charge amount of the battery 4 based on 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-on / off switching switch and the function button switch of the cordless telephone slave unit. An output corresponding to the switch input of the switch group 9 is supplied. Also, receiving the required charge amount from the required charge amount calculation means 7,
A callable time calculating means 10 for calculating the callable time by the cordless telephone handset based on the required charge amount, and a display for receiving the output of the callable time calculating means 10 and displaying the callable time of the cordless telephone handset Means 11 is provided. When the detection unit 8 detects that the cordless telephone subunit is connected to the charger, the mode management unit 1 determines that the charging mode is set, and that the cordless telephone subunit is not connected to the charger. When detected, the mode management means 1
Is determined to be a use mode. Then, in response to the switch input of the switch group 9, the mode management means 1 causes the charging mode,
Determine the operating status of the cordless handset in the use mode. The charging current supplied from the constant current circuit 2 to the battery is constant, but the operation mode of the cordless telephone handset and the battery 4
It is possible to switch to a plurality of preset constant current values according to the state of charge. The constant current switching means 3 creates an output for selecting a constant current value according to the operation mode based on the output indicating the operation state of the cordless telephone handset from the mode management means 1, and outputs the output. To switch the constant current value. In the case of the example of FIG. 1, the charge amount calculation means 5 receives the selection output of the constant current value from the constant current switching means 3 to know the constant current value of the charging, and the same output state of this selection output. The charging time based on the constant current value is known as time, and the charging amount is calculated as (constant current value) × (charging time) = (charging 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 supplied to the required charge amount calculation means 7 and subtracted from the required charge amount up to that point. When the battery is in a fully charged state (the required charge amount is zero), the constant current switching circuit 3 is output by the output of the required charge amount calculation means 7.
The selection output of is to select a constant current value during trickle charging, and the battery is in the trickle charging state to prevent overcharging. When the cordless telephone slave unit is in the use mode in which it is detached from the charger, the consumption amount calculating means 6 responds to the signal indicating the operating state of the cordless telephone slave device identified by the mode managing means 1, = (Current consumption according to operating state) × (duration of the operating state) The consumption is calculated and integrated. 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, and the required amount of charge is constantly managed, so that the charge time management until full charge can be performed reliably and accurately. Then, 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) = (the required charge amount when the quick charge is required) ) -Available capacity of the battery is calculated as (required required charge), and 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 manner, 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. FIG. 2 is a block diagram of an embodiment of the present invention, which is an example when a microcomputer (hereinafter referred to as CPU) is used for control. In FIG. 1, 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. A control circuit unit 32 controls the wireless circuit unit 31 and controls 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 function buttons, and 35 is a power on / off switch, which supplies the CPU 33 with an output indicating the operation state of each. Reference numeral 36 is a liquid crystal display as an example of display means, which includes dial numbers, time, display of the operating state of the handset (extension call, outside call, hold, incoming call, etc.), callable time display, battery The warning display of the necessity of charging the battery is displayed. 37 is a rechargeable battery such as a NiCd battery. Reference numeral 38 is a constant current circuit that supplies a constant current as a charging current to the battery 37. The constant current circuit 38 can change the constant current value by a control signal from the CPU 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. 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, a charging current flows through the battery 37. Therefore, this charging current is detected by the charging current detection circuit 39.
Detects and supplies a signal indicating that the child device 30 is connected to the charger 20 and is being charged to the CPU 33. The constant current value of the constant current circuit 38 described above is set as follows. (1) In the case of rapid charging (1) -a Power switch is off, slave unit is not operating (quick charging current) + (circuit current at rest) = constant current value A (1) -b Intermittent reception on standby While performing the quick charge (quick charge current) + (intermittent reception circuit current) = constant current value B Here, the stand-by intermittent reception is to detect the non-operation state and whether or not there is received data. In this operation mode, the intermittent reception state in which the wireless circuit unit 31 is operated 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 Non-operating state of intermittent reception (charging current during intermittent reception) + (circuit current during quiescent) = constant current value C (2) -b During intermittent reception (Charge current during intermittent reception) + (Circuit current during intermittent reception) = (Constant current value D) (3) Trickle charge after full charge (3) -a Non-operating state of intermittent reception (Trickle charge current) + (Circuit current at rest) = Constant current value E (3) -b Intermittent reception intermittent reception (Trickle charge current) + (Intermittent reception circuit current) = Constant current value F (4) Incoming call Medium (trickle charge current) + (circuit current at incoming call) = constant current value G The constant current value can be reduced or increased depending on the charging time and circuit current conditions. The CPU 33 discriminates the operation state as described above, and the constant current circuit 38
A constant current switching signal is supplied to. 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 slave unit 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 the operation stop state due to power off.However, the current consumption in each mode is fixed, so the CPU 33 sets 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 with a capacity of 400 mAH, it will not be fully charged unless it is charged with 600 mAH. Therefore, the charge loss coefficient (1.5 in the above example), which is (maximum required charge amount / capacity) = (charge loss coefficient), is calculated, and (battery consumption amount) x (charge loss coefficient) = (additional required charge amount) Do. 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 that is slightly smaller than the maximum required charge amount, a warning display is given on the liquid crystal display 36 to warn that the battery 37 is almost empty. When the user connects the mobile device 30 to the charger 20, the CPU3
A constant current value switching signal for selecting the constant current value A or B at the time of rapid charging is supplied from 3 to the constant current circuit 38 to forcibly enter the rapid charging state. And when the required charge amount is zero, that is, when it is fully charged, the CPU3
The constant current value switching signal from 3 selects the constant current value during trickle charging. As described above, the CPU 33 manages the charging time while monitoring the required charging amount. Further, the CPU 33 obtains the remaining capacity from the required charging capacity by the following formula: (maximum required charging capacity)-(currently required charging capacity) = (remaining capacity), (remaining capacity) ÷ (consumption current charge loss coefficient during call ) = (Callable time) Calculate the callable time by the calculation. Then, the callable time is displayed on the liquid crystal display 36. In addition, 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 adjusted. By turning off a certain number of light emitting diodes sequentially from the end, it is possible to visually display the exhausted state of the battery. This display also indicates that a call can be made by the number corresponding to the number of light emitting diodes that are lit. The callable time may be obtained by detecting the voltage of the battery, and may be displayed by the liquid crystal display or the plurality of light emitting diodes. FIG. 3 is a flowchart 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). If the handset 30 is not connected to the charger 20, the handset use mode is entered, and the flow advances to step 102 to determine 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 10)
5) One of the incoming call states (step 106) is identified, and then 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 that usage state is calculated (step 11
3,114,115). Next, the calculated battery consumption amount is converted into an additional required charge amount and added to the required charge amount (step 116). When 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). After the battery consumption in this mode is calculated (step 120), step 116
Then, the battery consumption is converted into an additional required charge amount and added to the required charge amount. Upon completion of step 116, the process returns to step 101. When it is determined in step 101 that the slave device 31 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 handset 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, when the required charge amount exceeds the predetermined value TH and the charge is kept below a certain level (step 125), the charge current from the constant current circuit 38 is constant current values A and B according to the standby reception. It is set (step 126). Then, the duration of that state is measured (step 12
7) The charge amount is calculated (step (128). Then, the charge amount is subtracted from the required charge amount (step 129). As a result of the check, the required charge amount is less than or equal to the predetermined value TH When the value is equal to or more than a certain value (step 130), the charging current is set to the constant current values C and D in response to the standby reception (step 131), and then the process proceeds to step 127 and the duration of the state is maintained. After the measurement, the charge amount is calculated, and the calculated charge amount is subtracted from the required charge amount (step 12
8,129). When step 129 ends, the process returns to step 101. As a result of checking the required amount of charge in step 124, when charging is completed and it is determined that the battery is fully charged (step 132), the constant current values E and F during trickle charging are set as the charging current according to the standby reception. It is set (step 133) and the process returns to step 101. As a result of checking the state of the child device 30 in step 122, if the incoming call is identified (step 134), the constant current value G is set (step 135), and then the process returns to step 101. When it is determined in step 121 that the power is off, the process proceeds to step 136, and it is determined whether or not 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. If it is determined in step 136 that charging is complete, step 1
After proceeding to 40 and setting the constant current value E, step 101
Return to.

【The invention's effect】

In the present invention, the amount of charge and the amount of charge of the battery are constantly monitored and calculated, and these are subtracted from and added to the required amount of charge to constantly detect the required amount of charge at the present time. Therefore, the remaining capacity of the battery can be quantitatively obtained from the required charge amount. Therefore,
By quantitatively displaying it on the display means, the remaining battery level can be constantly monitored. When using the cordless telephone slave unit, the user can know in advance how much communication is possible by looking at the battery remaining amount display displayed on the display means. In addition, while managing the status of the cordless handset, it constantly detects the amount of charge required at the current point in time, so you can always know the remaining battery capacity. The callable time of whether the time can be guaranteed can be accurately displayed even when the user is using the cordless telephone handset. Therefore, the user can make a call with peace of mind. Further, it is possible to easily and surely 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.

[Brief description of drawings]

FIG. 1 is a block diagram of an example of a conceptual configuration of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIG.
It is a flow chart for explaining operation of the example of a figure. 1; mode management means 2, 38; constant current circuit 3; constant current value switching means 4, 37; battery 5; charge amount calculation means 6; battery consumption amount calculation means 7; required charge amount calculation means 33; CPU 36; liquid crystal display

Front Page Continuation (72) Inventor Kozo Kobayashi 1-1-6 Uchiyuki-cho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Takeo Saito 1-1-6 Uchiyuki-cho, Chiyoda-ku, Tokyo Nihon Telegraph Phone Co., Ltd.

Claims (2)

[Claims] 1. A rechargeable battery built into a cordless telephone handset, a means for obtaining a charge amount of the rechargeable battery by multiplying a charge current by a charge time, and a battery consumption amount of the rechargeable battery as a consumption current. A cordless system comprising means for obtaining the remaining capacity of the rechargeable battery from the obtained charge amount and battery consumption, and display means for quantitatively displaying the obtained remaining capacity. Talking time display device for telephone handsets. 2. A mode managing means for managing an operating state of the cordless telephone slave unit, a charge amount calculating means for obtaining a charge amount of the battery of the cordless telephone slave unit from a charging current and a charging time, and the mode managing means. Based on the consumption amount calculating means that receives the output and obtains the battery consumption amount from the consumption current and the operating time according to the operating state, the charge amount from the charge amount calculating means, and the consumption amount from the consumption amount calculating means. A required charge amount calculation means for calculating a required charge amount of the battery, a callable time calculation means for calculating a callable time by the cordless telephone handset based on the required charge amount, and a callable time calculation means A callable time display device comprising a display means for receiving the output and displaying the callable time.