JPH04217827A - Electronic appliance provided with battery - Google Patents

Abstract

PURPOSE:To prevent overcharge of a battery in an electronic appliance and to know the residual life of battery by depressing a key during operation of the electronic appliance. CONSTITUTION:An electronic appliance provided with a battery comprises a charging circuit 33, a memory 21 storing operational parameters and constants, and a CPU 2O which calculates the charging time and provides the calculated charging time to the charging circuit 33 and then calculates the residual life of the battery based on a command provided by an operating key 24 and providing thus calculated residual life to a print head 30.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device such as a printer equipped with a battery that can be charged by connecting an adapter or the like, and more particularly to a battery charging function and a printing function of remaining usage time.

0002

[Prior Art] Generally, in battery-equipped electronic equipment that supplies current from a battery to loads such as motors and electronic circuits, the battery and the control unit are connected to a charging circuit via a charging current supply line and a charging signal line, respectively. It has been done. When the user sees the alarm lamp that indicates that the battery voltage has dropped and entered the alarm area, the user must
Connect the adapter and press the charging switch. When the charging switch is pressed, a charging signal from the control section is turned on and a timer means for setting a charging time is also activated. When the charging signal is turned on, the DC output from the AC adapter is supplied to the battery as charging current via the charging circuit. When the timer means times out, the charging signal is turned off and the charging current is also stopped.

0003

[Problem to be Solved by the Invention] In conventional electronic devices with batteries, the battery is sufficiently charged in advance even if the alarm lamp that indicates that the battery voltage has dropped and entered the alarm area is not lit. When I wanted to keep it running, I connected the adapter to the charging circuit and charged it. In this case as well, a fixed charging time is set in the timer means regardless of the remaining charge level, and charging continues until the timer runs out, resulting in overcharging, which only shortens the life of the battery. There was also the risk of an explosion if the internal pressure increased.

[0004] Also, while the device is in use, there is no function to know how much time the device can be used with the battery (hereinafter referred to as remaining usage time), so it is difficult to know when the battery voltage has dropped and entered the alarm range. There was also the problem that users used the device until the alarm lamp came on to notify them, and they had to stop work to charge the battery.

[0005] The present invention provides a battery that does not overcharge even if it is charged when the alarm lamp indicating that the voltage of the battery has entered the alarm range is not lit, and that the remaining usage time can be known at any time while the device is in use. The purpose is to provide electronic equipment.

[0006]

[Means for Solving the Problems] In order to achieve the above object, in the electronic device with a battery of the present invention, the load amount for each load and the discharge amount per unit load amount of each load are input and the total a discharge amount calculation means for calculating the discharge amount; and a charge determination means for outputting a charge determination signal for determining whether to turn on a charge signal to the battery charging means by comparing the total discharge amount and a limit discharge amount. , a timer value calculation means for calculating the charging time from the total discharge amount and the charging current amount, and a timer out signal for setting the charging time based on the charging determination signal from the charging determining means, counting and turning off the charging signal. It is equipped with a timer means for outputting, or further inputs the discharge amount per unit load of each load, the total discharge amount, and the limit discharge amount based on instructions from the input means, and calculates the remaining usage time. and a remaining usage time calculation means for outputting the remaining usage time to the printing means.

[0007]

[Operation] In the electronic device with a battery configured as described above, the discharge amount calculation means calculates the discharge amount to each load from the load amount to each load and the discharge amount per unit load amount of each load. Then, the total discharge amount is determined by summing the discharge amount to each load. Further, the charge determining means compares the total discharge amount and the limit discharge amount to determine whether or not to turn on the charge signal. Further, the timer value calculation means calculates the charging time to be set in the timer means from the total discharge amount and the discharge current amount. When the total amount of discharge exceeds the limit amount of discharge, the charging signal from the control section is turned on and the timer means for setting the charging time is also activated. When the charging signal is turned on, charging current is supplied to the battery. When the timer means times out, the charging signal is turned off and the supply of charging current is also stopped.

[0008] Also, when you want to know the remaining usage time while using the device, you input an instruction from the input means, and the remaining usage time calculation means calculates the remaining charge amount from the limit discharge amount and the total discharge amount, and then calculates the remaining charge amount. The remaining usage time is calculated from the remaining discharge amount and the discharge amount per unit load amount of each load, and is output to the printing means.

Therefore, according to the battery-equipped electronic device of the present invention, even if the battery is charged when the voltage of the battery has not yet entered the alarm range, the battery is charged by calculating the discharging time from the total discharge amount up to that point. There is no over-discharging, and you can always know the remaining usage time while using the device.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Note that elements common to each drawing are given the same reference numerals.

FIG. 1 is a functional block diagram showing the basic configuration of the present invention. The discharge amount calculation means 1 includes a load amount storage means 2 which stores the amount of load on each load, a unit discharge amount storage means 3 which stores the amount of discharge per unit load of each load, and a battery to each load. It consists of a total discharge amount storage means 4 that stores the total discharge amount since the start of supplying current, a first discharge amount calculation means 5, and a second discharge amount calculation means 6. The first discharge amount calculation means 5 inputs the load amount and the discharge amount per unit from the load amount storage means 2 and the unit discharge amount storage means 3,
Find the discharge amount of that load. The second discharge amount calculation means 6 inputs the discharge amount and the total discharge amount from the first discharge amount calculation means 5 and the total discharge amount storage means 4, adds them together, and outputs the sum to the total discharge amount storage means 4 again. do. The charging determining means 7 comprises a limiting discharge amount storing means 8 and a comparing means 9, and the comparing means 9 compares the contents of the total discharge amount storing means 4 and the limiting discharge amount storing means 8 to determine whether or not to charge. and outputs a charging determination signal to the control signal generating means 15. Timer value calculation means 10
These are a charging current amount storage means 11 for storing the amount of charging current supplied to the battery, a charging time storage means 13 for storing the charging time set in the timer means 14, and a charging time calculation means 12.
It consists of The charging time calculation means 12 inputs the total discharge amount and the charging current amount from the total discharge amount storage means 4 and the charging current amount storage means 11, calculates the charging time, and stores it in the charging time storage means 1.
Output to 3. The control signal generating means 15 is the charge determining means 7.
When the charging determination signal from the charging circuit 16 is inputted, a charging signal is turned on to the charging circuit 16, and the timer means 14 is set to a charging time from the charging time storage means 13, and is activated. When the timer means 14 times out, a timer out signal is output from the timer means 14 to the control signal generating means 15,
The control signal generating means 15 turns off the charging signal.

Further, when the remaining usage time calculation means 18 inputs an instruction from the input means 17, it inputs the total discharge amount storage means 4 and the limit discharge amount storage means 8, calculates the remaining charge amount, and further stores the unit discharge amount. The remaining usage time is calculated by inputting the discharge amount per unit load of each load from the means 3, and the printing means 19
Output to.

FIG. 2 is a configuration block diagram of a serial printer showing an embodiment of the present invention using a microcomputer, and FIG. 3 is a detailed diagram of the charging circuit of FIG. 2. The central processing unit 20 (hereinafter referred to as CPU 20) has a storage device 21 (hereinafter referred to as memory 21) and an input/output port 22 (hereinafter referred to as memory 21).
(hereinafter referred to as I/O port 22) through lines 39 and 40. Memory 21 is a control program area 21
a, unit discharge amount storage area 21b, total discharge amount storage area 21c, battery capacity storage area 21d, comparison reference amount storage area 21e, charging current amount storage area 21f, charging time storage area 21g, constant charging time storage area 21h, data It is divided into storage areas 21i, each of which stores a control program, discharge amount per unit load amount, total discharge amount, battery capacity, comparison reference amount, charging current amount, charging time, constant charging time, and load amount.

The input/output driver 23 (hereinafter referred to as I/O driver 23) has an I/O port 22, a printer interface 27, a space motor 28, a line feed motor 29, a print head 30, and lines 44, 47, and 4, respectively.
They are connected at 8, 49, and 50. Also, I/O port 22
are operation key 24, alarm lamp 25, ready lamp 2
6, the output side of the A/D converter 32, the charging signal input part of the charging circuit 33, and lines 41, 42, 43, 45, 4, respectively.
It is connected with 6. The charging circuit 33 is as shown in FIG. That is, the transistor T which is the charge signal input section
The base of R1 is connected to the line 46 mentioned above, and is further connected to +5V via a resistor R1. Furthermore, the emitter of the transistor TR1 is connected to ground, and the collector is connected to the transistor T through a resistor R3.
It is connected to the base of R2. The emitter of transistor TR2 is connected to one terminal 35a of socket 35 and line 5.
3, and the collector is connected to the + pole of the battery 34 and the A/D converter 3 via a diode D1 and a resistor R4.
It is connected to the input side of 2 by a line 51. battery 34
A nickel-cadmium battery (hereinafter referred to as a Ni-Cd battery) is used. Diode D1 is used to inhibit reverse bias from battery 34, and resistor R4 is used to limit charging current. A/D converter 32 is connected to battery 34
This is a battery voltage detector that converts the output voltage value from an analog value to a digital value. Line 51 and line 53 are connected to form line 54, which is connected to each circuit that is a load that consumes current. The negative pole of the battery 34 and the other terminal 35b of the socket 35 are connected to ground via a line 52. The AC adapter 36 is connected to plugs 37 and 38 through lines 55 and 56 and lines 57 and 58, respectively. The AC adapter 36 is connected to an AC 100V socket with a plug 38, and after voltage transformation, rectification is performed.

Next, the operation of the present invention will be explained.

FIG. 4 is a flowchart showing an operation for detecting a battery voltage drop in a serial printer according to an embodiment of the present invention, and FIG. 5 is a flowchart showing a charging operation of a serial printer according to an embodiment of the present invention. First,
When a power switch (not shown) of the electronic device is turned on, the electronic device is initialized by a control program. After initialization, the electronic device is controlled by the control program and the CPU 20. In step S1, the AC adapter 3 shown in FIG.
6 is connected to an electronic device. Although the means for checking is not shown, it is checked, for example, whether voltage is applied to one terminal 35a of the socket 35. If the AC adapter 36 is not connected, the mode becomes battery mode and the process proceeds to step S2. Step S2
The voltage value of the battery 34 is converted from an analog value to a digital value by the A/D converter 32, and the value is compared with the comparison reference amount 5 stored in the comparison reference amount storage area 21e of the memory 21.
．． 8V and check whether it is 5.8V or less. (The voltage of the Ni-Cd battery gradually decreases to around 5.8V, and rapidly decreases below 5.8V.) If the voltage value of the battery 34 exceeds 5.8V, proceed to step S4. . In step S4, since the voltage of the battery 34 is normal, the ready lamp 26 lights up, notifying the operator that printing is to begin. CPU2 at the same time
0, memory 21, I/O port 22, I/O driver 2
3. Printer interface 27, space motor 28
, line feed motor 29, print head 30, and other circuit loads are stored in the data storage area 21i of the memory 21.
to be memorized. Then, after a predetermined period of time, for example, 3 minutes, the load amount for each load and the discharge amount per unit load amount are sequentially read out from the data storage area 21i and the discharge amount storage area 21b per unit load amount. The multiplied value is added to the total discharge amount in the total discharge amount storage area 21c, and the result is stored again in the total discharge amount storage area 21c. Repeat this step by step for all loads. As a result, the amount of full load after 3 minutes has passed is determined and added to the total amount of discharge. (Hereinafter, this process will be referred to as the discharge amount calculation process) Total discharge amount storage area 21
EEPROM is used in C so that the stored contents will not be erased even when the power switch is turned off.

[0017] Here, the method for determining the amount of discharge will be explained. Load amount is spacing motor 28, line feed motor 2
9 is the number of pulses that activate the motor, and includes the alarm lamp 25, ready lamp 26, printer interface 27, print head 30, memory 21, and CPU 20.
, I/O port 22, I/O driver 23, A/D converter 32, charging circuit 33, etc.
SEC]. Further, the discharge amount per unit load is the discharge amount [A] per pulse for the spacing motor 28 and line feed motor 29, and the discharge amount [A] for the alarm lamp 25, ready lamp 26, and printer interface 27.
, the print head 30, the memory 21, the CPU 20, the I/O port 22, the I/O driver 23, the A/D converter 32, the charging circuit, etc. are discharged per second [A].

That is, when 3 minutes have passed in the data storage area 21i, the load amount stored as each load amount is
: Number of pulses of the spacing motor NLF: Number of pulses of the line feed motor P: Printing time [SEC] T: Time of idle state [SEC], discharge per unit load stored in the unit discharge amount storage area 21b Q: Discharge amount per pulse of the spacing motor [A] QLF: Discharge amount per one pulse of the line feed motor [A] I: Discharge amount per second of the print head [A] Q
IDLE: If the amount of discharge per second in idle state [A], then the amount of discharge q[A] after 3 minutes has passed is q[A]
]=QN+QLF・NLF+QIDLE・T+P・I. To make it easier to understand, converting this into ampere hours (hereinafter referred to as Ah), it becomes Q = 1/20q [Ah].

After the discharge amount calculation process, the process returns to step S1. Steps S1, S2, and S4 are then repeated, and when the operator presses the operation key 24 between steps S2 and S4, the remaining usage time calculation process begins.

First, the discharge amount per second of each load is read out from the unit discharge amount storage area 21b and added to obtain the total discharge amount per second X[A].X[A]=Q+QLF+QIDLE+I Become.

Next, the battery capacity and total discharge amount are read from the battery capacity storage area 21d and the total discharge amount storage area 21, respectively, and subtracted to determine the remaining charge amount Y [Ah]. Dividing this value by X [A] gives the remaining usage time Z [h
]=Y/X is found.

The determined remaining usage time Z[h] is printed by the print head 30.

Note that the discharge amount calculation process has the first priority, and an interrupt signal is generated every three minutes after initialization.
It is processed. While repeating this loop of steps S1, S2, and S4, in step S2, the battery 3
When the voltage of 4 becomes 5.8V or less, the process moves to step S3. In step S3, the alarm lamp 24 shown in FIG. 2 is turned on. Thereafter, the process returns to step S1, and steps S1,
Repeat the loop of S2 and S3. When the operator noticed the alarm and turned off the power switch,
Connect the plug 37 of the C adapter 36 to the socket 35 of the electronic device.
and turn on the power switch. After initialization, as described above, it is checked whether or not the AC adapter 36 is connected, and the adapter mode is entered, and the process proceeds from step S1 to step S5 shown in FIG. Step S5
The voltage of the battery 34 is sensed. In step S6, it is compared with the comparison reference amount 5.8V stored in the comparison reference amount storage area 21e of the memory 21 to check whether it is less than 5.8V. If the voltage is 5.8V or less, the process advances to step S7, and the memory 21
Constant charging time “15” from constant charging time storage area 21h
time" is set in the register of the CPU 20. In step S8, timer counting is started, and the output level of the charging signal to the charging circuit 33 shown in FIG. 3 is set to "H" via the I/O port 22. Transistor When the base of TR1 is set to level “H”, the transistor TR
1 is turned on, and current flows between the collector and emitter. As a result, the transistor TR2 is turned on, and the charging current rectified by the AC adapter 36 flows to the battery 34 through the emitter and collector of the transistor TR2. The charging current value is 1/ of the battery capacity value.
It should be about 10. For example, if the battery capacity value is 12Ah, the charging current value is 1.2A. In step S9, it is checked whether the count is out or not, and when the count is out, the process proceeds to step S10. In step S10, the charging signal is set to the level "L" and the charging current is stopped. Also, at this time, the contents of the total discharge amount storage area 21c are erased. If the voltage exceeds 5.8V in step S6, the process advances to step S11. In step S11, the total discharge amount storage area 2 of the memory 21 is
1c and the battery capacity storage area 21d, the percentage of the total discharge amount is determined, and the reference value "10%" is read out from the comparison reference amount storage area 21e for comparison. If the discharge amount of the battery 34 exceeds 10%, that is, if the remaining charge amount of the battery 34 is less than 90%, the process advances to step S12, and the total discharge amount in the total discharge amount storage area 21c of the memory 21 is stored in the charging current storage area. The charging time "H time" is obtained by dividing by the charging current of 21f, and is stored in the charging time storage area 21g. In step S13, the charging time "H time" is set in the register of the CPU 20 from the charging time storage area 21g, and the process returns to step S8. In step S11, if the discharge amount of the battery 34 is 10% or less, that is, if the remaining charge amount of the battery 34 is 90% or more, charging is not necessary. Note that charging is performed in an idle state when the electronic device is not printing.

Therefore, even if the battery voltage is 5.8V or higher, if you want to keep the battery sufficiently charged, use A.
When the C adapter is connected and the power switch is turned on, the charging time is determined and the battery is charged by the amount of discharge, so there is no overcharging. In this embodiment, the ratio of the total discharge amount to the battery capacity is determined to determine whether or not to charge the battery, and the ratio of the total discharge amount to the battery capacity is compared with the reference amount for comparison. However, a limit discharge amount may be determined and directly compared with the total discharge amount.

[0025]

[Effects of the Invention] The present invention provides electronic equipment with a battery.
Discharge amount calculation means that calculates the total discharge amount from the load amount for each load and the discharge amount per unit load amount of each load, and a charging signal to the battery charging means that compares the total discharge amount and the limit discharge amount. charge determination means for outputting a charge determination signal for determining whether to turn on or not, a timer value calculation means for calculating charging time from the total discharge amount and charging current amount, and a timer value calculation means based on the determination signal from the charge determination means. It is equipped with a timer means for setting and counting the charging time and outputting a timer-out signal to turn off the charging signal, and when the total discharge amount exceeds the limit discharge amount, the charging signal from the control section is turned on and the charging time is turned off. The timer means set also operates, and when the timer means times out, the charging signal is turned off, so that when the AC adapter is connected, charging is automatically performed in an amount commensurate with the total amount of discharge.

[0026] Therefore, there is no possibility of overcharging, shortening the life of the battery, or risk of explosion.

[0027] Also, by providing a function to know the remaining usage time, you can know the remaining usage time in advance while using the device on battery, so you can check whether it is better to charge it first or not based on the current remaining charge. You can determine whether you are able to complete the task sufficiently.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing the basic configuration of the present invention.

FIG. 2 is a configuration block diagram of a serial printer showing one embodiment.

FIG. 3 is a detailed diagram of the charging circuit of FIG. 2;

FIG. 4 is a flowchart of an operation for detecting a battery voltage drop in a serial printer according to an embodiment of the present invention.

FIG. 5 is a flowchart showing a charging operation of a serial printer according to an embodiment of the present invention.

[Explanation of symbols]

1 Discharge amount calculation means 4 Total discharge amount storage means 7 Charging determination means 10. Timer value calculation means 13 Charging time storage means 14 Timer means 15 Control signal generation means 16 Charging circuit 18 Remaining usage time calculation means

Claims (3)

[Claims] [Claim 1] A battery-equipped electronic device that supplies current from a battery to each load such as a motor or an electronic circuit, comprising a load storage means for storing a load amount for each load, and a unit load amount per unit load of each load. unit discharge amount storage means for storing the discharge amount of the battery; first discharge amount calculating means for calculating the discharge amount by inputting the load amount and the discharge amount per unit load amount; a total discharge amount storage means for storing the total discharge amount from the time when the current is started to be supplied to until the first discharge amount calculation means calculates the discharge amount; and a discharge amount from the first discharge amount calculation means. and a second discharge amount calculation means that inputs and adds the total discharge amount and the total discharge amount of the total discharge amount storage means and outputs the sum to the total discharge amount storage means. with electronic equipment. [Claim 2] A battery-equipped electronic device that has a battery that supplies current to each load such as a motor and an electronic circuit, and is equipped with a battery charging means that charges the battery for a predetermined period of time. A discharge amount calculation means that calculates a total discharge amount from the discharge amount per unit load of each load, and a device that compares the total discharge amount with a limit discharge amount and turns on a charging signal to the battery charging means. a timer value calculation means that calculates the charging time from the total discharge amount and the charging current amount; and timer means for outputting a timer-out signal for setting, counting, and turning off the charging signal. 3. Based on an instruction from the input means, the discharge amount per unit load of each load, the total discharge amount, and the limit discharge amount are input, and the remaining usage time is calculated and outputted to the output means. The battery-equipped electronic device according to claim 1 or 2, further comprising a time calculation means.