JP2002051482A - Charger for printer and backup power supply for printer - Google Patents

Abstract

(57) [Problem] To provide a printer and a printer backup power supply charging device capable of notifying and confirming a replacement time of a backup power supply for supplying power for performing a required backup operation to the printer. . A backup power supply includes a voltage monitoring means for monitoring a voltage between terminals of the backup power supply, and a time measuring means for measuring an elapsed time of charging and discharging of the backup power supply. When the inter-terminal voltage at the time of completion of charging of the backup power supply becomes equal to or less than a predetermined operation voltage within a predetermined reference time or less, the state of the backup power supply is determined to be defective and a warning is issued.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer and a charging device for a backup power supply for a printer, and more particularly to an RT built into the printer when the main power supply of the printer is turned off.
The present invention relates to a charging device for a backup power supply such as a secondary battery that supplies power to C and the like.

[0002]

2. Description of the Related Art Conventionally, some electronic devices such as printers perform a predetermined backup operation by using power supplied from a pre-charged secondary battery or the like when a main power supply is cut off. For example, in an inkjet printer, in order to prevent the ink from hardening, the print head is moved to the home position regardless of the state of the main power supply being turned off by the user or the outlet being disconnected. The power supply cannot be cut off immediately because it needs to be capped.

That is, in many ink jet printers having a switching power supply, the power switch is controlled on the secondary side, and the power supply switch is completely turned off unless the outlet is unplugged.
It does not enter the FF state. The power supply (switching regulator) performs intermittent oscillation with a low duty ratio voltage waveform while the power switch is turned off, and the state of the power switch on the secondary side is continuously monitored by a CPU or the like. When the power switch is turned off, the CPU performs a capping operation of the print head and then sends a predetermined signal to the power supply. Upon receiving this signal, the power supply shifts to the above-described intermittent oscillation state.

Further, in a printer or the like, when the main power is turned off, an EEP is stored in order to save the data until the next power-on.
Writing control information during printer operation to ROM, etc.
It is also necessary to perform a memory backup operation.

Further, in the ink-jet printer, when the power is turned on, several kinds of pumping operations in which the amount of ink suction is changed according to the length of unused time are performed, or the ink-jet printer is independently or independently supplied from the host computer. In order to print the printing time on the edge of the printing paper according to the command, a real-time clock (RealT
im Clock (hereinafter referred to as RTC). The RTC is a digital IC device that outputs a current time when a predetermined signal is input, for example, month, month, day, hour, minute, and second.
Must be operated even when the main power supply of the printer is turned off.

Conventionally, an electronic device such as a printer incorporates an electric double-layer capacitor and a secondary battery described later as a backup power source, and these are charged while the power is on, and the device is charged. When the power switch is turned off, the RTC is continuously operated with the charged power, or the memory is backed up.

A specific description will be given of a case where the RTC in the printer is continuously operated. In the first example, a secondary battery such as a Li battery or a Ni-Cd battery is built in the printer, and the RTC is operated by the power discharged from the secondary battery. That is, in the first example, for example, as shown in FIG. 6, a Li battery 81 is provided in the printer,
RTC is carried out by the power constantly supplied from the Li battery 81.
83 is operating. When a predetermined signal 86 is input from the CPU 85, the RTC 83 outputs a digital signal 87 representing the current time to the CPU 85.

In a second example, a high-performance capacitor called a super capacitor, a gold capacitor, an electric double layer capacitor, or the like is built in a printer, and the capacitor is charged while the power of the printer is turned on. When the power is turned off, the charge
Is operated continuously. That is, the second conventional example includes such a capacitor 91 as shown in FIG. 7, for example. The RTC 93 operates with power supplied from the main power supply 98, and the capacitor 91 is charged with power supplied from the main power supply 98 while the power of the printer is turned on. When the power of the printer is turned off, the RTC 93
Works continuously. Note that the RTC 93 outputs a digital signal 97 representing the current time to the CPU 95 when a predetermined signal 96 is input from the CPU 95, as in the first example.

[0009]

However, the charging / discharging ability of a backup power supply such as an electric double layer capacitor or a secondary battery decreases as the number of charging / discharging increases.
Specifically, this decrease in charge / discharge capability does not indicate a specified inter-terminal voltage even though charging is completed,
Even if the charging is completed and the specified inter-terminal voltage is indicated, it is determined that the inter-terminal voltage drops rapidly thereafter. However, the conventional printer and the printer backup power supply charging device do not have a means for notifying or confirming the time of replacement of the backup power supply. The print head movement and capping become unstable, memory backup becomes insufficient,
There is a problem that time measurement becomes inaccurate.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to notify and confirm the replacement time of a backup power supply for supplying power for performing a required backup operation to a printer. It is an object of the present invention to provide a printer capable of charging a printer and a backup power supply for the printer.

[0011]

In order to achieve the above object, in a printer according to the present invention, a terminal voltage at the time of completion of charging of a backup power supply for supplying power for performing a predetermined backup operation to a printer control unit is determined. The state of the backup power supply is determined by measuring the time until the voltage becomes equal to or lower than the operating voltage.

That is, in the invention according to claim 14, a printer mechanism, a printer controller for controlling the printer mechanism, a main power supply for supplying power to the printer mechanism and the printer controller, and charging / discharging. A backup power supply for supplying power for performing a predetermined backup operation to the printer control unit by the discharging, and when the main power supply is in an ON state, the power supply of the main power supply to the backup power supply. A voltage monitoring means for monitoring a voltage between terminals of the backup power supply, and a time measuring means for measuring an elapsed time of charging / discharging of the backup power supply. When the voltage between terminals falls below a predetermined operating voltage within a predetermined reference time, it is determined that the state of the backup power supply is defective. It is characterized in that a warning Te.

Since the user is notified that the backup power supply needs to be replaced, the user can immediately replace the defective backup power supply with a normal backup power supply, and move and cap the print head in a stable and reliable manner. be able to. For this reason, it is possible to always keep the print head in an optimal state by preventing ink drying and the like. Further, since the memory can be sufficiently backed up, important data can be reliably stored. Further, since the time measurement can be accurately performed, the management of the task schedule and the like can be reliably performed.

Further, in order to achieve the above object, in the printer according to the present invention, the terminal voltage at the time of completion of charging of a backup power supply for supplying power for performing a predetermined backup operation to the printer control unit is detected. The state of the backup power supply is determined.

That is, according to the third aspect of the invention, a printer mechanism, a printer controller for controlling the printer mechanism, a main power supply for supplying power to the printer mechanism and the printer controller, A backup power supply for supplying power for performing a predetermined backup operation to the printer control unit by the discharging, and when the main power supply is in an ON state, the power supply of the main power supply to the backup power supply. A voltage detecting means for detecting a voltage between terminals of the backup power supply, and a voltage comparing means for comparing the terminal voltage detected by the voltage detecting means with a predetermined reference voltage. When the voltage between the terminals at the time of completion of charging of the backup power supply is equal to or lower than the predetermined reference voltage, the state of the backup power supply is defective. It is characterized in that the decision to issue a warning.

Since the quality of the backup power supply can be immediately determined based on the voltage between the terminals at the time of completion of the charging of the backup power supply, if the backup power supply is defective, useless charging thereafter can be avoided. Electric energy can be saved.

The invention according to claim 5 is characterized in that the warning is issued and the backup power supply cannot be charged.

If the charging operation is continued with respect to the defective backup power supply, in the worst case, a fire or the like may occur. Therefore, the charging operation to the backup power supply is disabled to prevent the above-mentioned damage. It is possible to do.

In the above, the backup power supply comprises:
It can be constituted by a secondary battery or a capacitor.

Further, not only the printer but also the charging device of the backup power supply for the printer can achieve the same operation and effect with the same configuration. That is, in order to achieve the above object, a printer backup power supply charging device according to the present invention provides a printer that supplies power for performing a predetermined backup operation to a printer having a main power supply when the main power supply is not in an ON state. A backup power supply for a printer, which is capable of repeating charge and discharge, and in a charging device for a printer backup power supply for supplying power for performing the backup operation by the discharge, while monitoring a voltage between terminals of the backup power supply, The state of the backup power supply is defective when a real-time clock for measuring the elapsed time of charging and discharging of the backup power supply and when a terminal voltage at the time of completion of charging of the backup power supply becomes a predetermined operating voltage or less within a predetermined reference time or less. And issuing a warning by determining that

Further, in order to achieve the above object, in the printer backup power supply charging device according to the present invention, a printer having a main power supply is supplied with power for performing a predetermined backup operation when the main power supply is not in an ON state. A backup power supply for a printer that supplies and repeats charging and discharging, and detects a voltage between terminals of the backup power supply in a charging device for the backup power supply for a printer that supplies power for performing the backup operation by the discharge. And a real-time clock for comparing the detected inter-terminal voltage with a predetermined reference voltage, and when the inter-terminal voltage at the time of completion of the charging of the backup power supply becomes a predetermined reference voltage or less for a predetermined reference time or less, A CP which issues a warning by determining that the state of the backup power supply is bad
U is provided.

According to a tenth aspect of the present invention, the CPU issues the warning and disables charging of the backup power supply.

In the above, the backup power supply comprises:
It can be constituted by a secondary battery or a capacitor. The charging device may be configured to be externally attached to a printer.

[0024]

FIG. 1 is a schematic configuration diagram showing an embodiment of a printer according to the present invention. This printer is powered by O
This is an inkjet printer provided with a charging device for a backup power supply for continuously operating the above-mentioned RTC at the time of FF. As shown in FIG.
, Print engine 4, main power supply unit 6, RT
It has a C unit 8.

The printer controller 2 includes a CPU 10,
ROM 12, RAM 14, EEPROM 16, mechanical interface (I / F) 18, host interface (I
/ F) 20, which are interconnected by a bus 22.

The print engine 4 includes a print head 42
And a carriage mechanism including a carriage 43 and the like, and a paper feed mechanism including a paper feed (PF) motor 44 and the like. The paper feed mechanism includes a PF motor 44 and a paper feed roller (not shown), and sequentially feeds a print recording medium such as a recording paper 45 to perform sub-scanning. The carriage mechanism includes a carriage 43 on which the print head 42 is mounted,
A carriage (CR) motor 43a for moving the carriage 43 via a timing belt 46 and the like;
The print head 42 is caused to perform main scanning. The print head 42 discharges minute ink droplets using a piezoelectric element. The carriage 43 returns to the home position 43b in a predetermined case in order to perform various maintenances on the print head 42. For example, when the power is turned off, after the carriage 43 returns to the home position 43b, the above-described capping operation of capping the ink ejecting unit of the print head 42 is performed to prevent drying of the ink.

The main power supply unit 6 includes a switching regulator (not shown) therein and a power supply cable 30,
AC power is supplied from a commercial power supply (not shown) via the power plug 32. For example, 42V power is supplied to the print head 42 and the like of the print engine 4 and 5.0V or 3.3V power is supplied to the printer controller 2 and the like. Supply. The main power supply unit 6 is connected to a panel switch 5 provided on a printer panel, as shown in FIG. For example, the panel switch 5 is turned on when pressed by the user, and turned off when pressed again. The main power supply unit 6 also receives a signal from the panel switch 5 and is turned on similarly.
/ OFF, even if the panel switch 5 is turned off, as long as the power plug 32 is not removed from the outlet.
Enter a predetermined sleep state. Here, the predetermined sleep state means that the power switch is turned off and the power supply to the printer mechanism such as the print engine 4 is cut off.
This means a case where the power is still supplied to the PU 10 and the like even though it is very small, and typically corresponds to the above-described intermittent oscillation state.

The RTC unit 8 has an RTC 34 and a backup power supply 36. Backup power supply 36
Includes a secondary battery 36a, a diode 36b, etc., and operates when the power of the printer is turned off.
4 can operate continuously. When a predetermined signal 10a is input from the CPU 10, the RTC 34 outputs a digital signal 34a representing the current time to the CPU 10 as in the above-described conventional example.

FIG. 2 is a detailed block diagram showing an embodiment of a backup power supply charging device provided in the printer of FIG. As shown in FIG. 2, this charging device has a power supply (Power Supply, hereinafter referred to as PS) 6A.
, An RTC 34, the CPU 10, and first and second switches 37 and 38.

The PS6A is supplied with a primary voltage and, for example, supplies 42 V to a printer driving unit such as the print engine 4.
Also, logic circuits such as the printer controller 2 and R
RTC 34 and backup power supply 36 of TC unit 8
Is supplied with a secondary voltage of 5.0V or 3.3V.

The RTC 34 has voltage monitoring / detection means 34A, a timer 34B, and a comparator 34C therein. The voltage monitoring / detecting means 34A constantly monitors and detects the terminal voltage of the secondary battery 36a. Comparator 34C
Changes the voltage between terminals of the secondary battery 36a to a predetermined operating voltage Re.
Compared with fV (for example, 1.5V + α), that is, the minimum voltage at which the above-mentioned backup function operates, when the voltage between the terminals of the secondary battery 36a becomes equal to or lower than the operating voltage RefV, the power supply ON signal 34d is output and the second switch is output. By turning ON 38, the PS6A is returned to the ON state. This power supply O
The N signal 34d is output, for example, for 3 minutes, and the PS 6A is in the ON state for only 3 minutes. The timer 34B counts the elapsed time, for example, the ON state time of the PS 6A, that is, the charging time of the secondary battery 36a and the subsequent discharging time.

The CPU 10 determines that the terminal voltage at the time when the charging of the secondary battery 36a is completed is a predetermined reference time, that is, until the terminal voltage at the time when the charging of the normal secondary battery 36a is completed becomes lower than the operating voltage RefV. Operating voltage Ref in less than time
V, or when the inter-terminal voltage at the time of completion of the charging of the secondary battery 36a becomes equal to or lower than the predetermined reference voltage Va, that is, the inter-terminal voltage at the time of completion of the charging of the normal secondary battery 36a, the second The secondary battery 36a is determined to be defective, and a warning 10b is issued to output a signal 10c that disables charging of the secondary battery 36a. Also, the panel switch 5 of the printer
When the power is turned on from the sleep mode, whether the power is turned on by the panel switch 5 is determined.
Various control operations are performed depending on whether the operation is performed by the TC 34 or not.

The first switch 37 has a panel switch 5 of the printer and another switch 37a which opens and closes simultaneously with the operation of the panel switch 5. When the panel switch 5 is turned off, the PS 6A shifts to the intermittent oscillation state unless the outlet is unplugged, and when the panel switch 5 is turned on again, the PS 6A returns to the state of outputting a normal secondary voltage. When the panel switch 5 is turned ON / OFF, the switch 37a opens and closes simultaneously in conjunction with each other, so that a signal 37b for transmitting ON or OFF of the panel switch 5 is output and transmitted to the CPU 10.

Next, the operation of the charging apparatus according to the present embodiment will be described with reference to the flowchart of FIG. 3 and the time chart of FIG. 4 in addition to FIGS. FIG.
The vertical axis indicates the voltage V between the terminals of the secondary battery 36a, and the horizontal axis indicates the time T, and shows the change in the voltage between the terminals due to charging and discharging of the secondary battery 36a.

First, with reference to FIGS. 3A and 4A, a first operation of the charging device when the secondary battery 36a is normal will be described. When the PS 6A is turned on by the power ON signal 34d from the RTC 34 at time Ta, charging of the secondary battery 36a is started (step S1). When the charging of the secondary battery 36a is completed at the time Tb (step S2), the voltage monitoring / detecting means 34A starts monitoring the voltage between the terminals of the secondary battery 36a, and the timer 34B determines whether the charging is completed. The counting of the elapsed time from Tb is started (step S3). Note that the voltage between the terminals of the secondary battery 36a at the time Tb of completion of the charging is the reference voltage Va. The comparator 34C continues the operation of comparing the inter-terminal voltage of the secondary battery 36a with the operating voltage RefV until the inter-terminal voltage of the secondary battery 36a becomes equal to or lower than the operating voltage RefV (step S4). Then, at time Tc, 2
When the voltage between the terminals of the secondary battery 36a becomes equal to or lower than the operating voltage RefV, the CPU 10 determines that the voltage between the terminals at the time when the charging of the secondary battery 36a is completed is equal to or lower than the operating voltage RefV for the predetermined reference time Tc-Tb or more. Judge, the secondary battery 3
6a is determined to be normal (steps S5 and S9).

Next, the first operation of the charging device when the secondary battery 36a is defective will be described with reference to FIGS. 3A and 4B. When the PS 6A is turned on by the power ON signal 34d from the RTC 34 at time Ta, charging of the secondary battery 36a is started (step S1). When the charging of the secondary battery 36a is completed at the time Tb (step S2), the voltage monitoring / detecting means 34A starts monitoring the voltage between the terminals of the secondary battery 36a, and the timer 34B determines whether the charging is completed. The counting of the elapsed time from Tb is started (step S3). Note that the voltage between the terminals of the secondary battery 36a at the time Tb of completion of the charging is the reference voltage Va. The comparator 34C continues the operation of comparing the inter-terminal voltage of the secondary battery 36a with the operating voltage RefV until the inter-terminal voltage of the secondary battery 36a becomes equal to or lower than the operating voltage RefV (step S4). Then, at time Td (<
At Tc), the voltage between the terminals of the secondary battery 36a becomes the operating voltage Ref.
When the voltage falls below V, the CPU 10 determines that the inter-terminal voltage at the time when the charging of the secondary battery 36a is completed is below the operating voltage RefV within a predetermined reference time Tc-Tb or less, and the secondary battery 36a is defective. (Step S
5, S6). Then, a warning is issued by voice or image (step S7), and the secondary battery 36
is transmitted (step S).
8).

Next, a second operation of the charging apparatus when the secondary battery 36a is normal will be described with reference to FIGS. 3B and 4A. When the PS 6A is turned on by the power ON signal 34d from the RTC 34 at time Ta, charging of the secondary battery 36a is started (step S11). When the charging of the secondary battery 36a is completed at time Tb (step S12), the voltage monitoring / detecting unit 34A
The terminal voltage of the secondary battery 36a is detected (step S1).
3), the comparator 34C compares the terminal voltage of the secondary battery 36a with the reference voltage Va (Step S14).
Then, the CPU 10 determines that the inter-terminal voltage of the secondary battery 36a at the charging completion time Tb is the reference voltage Va, and determines that the secondary battery 36a is normal (step S18).

Next, a second operation of the charging device when the secondary battery 36a is defective will be described with reference to FIGS. 3B and 4C. When the PS 6A is turned on by the power ON signal 34d from the RTC 34 at time Ta, charging of the secondary battery 36a is started (step S11). When the charging of the secondary battery 36a is completed at time Tb (step S12), the voltage monitoring / detecting unit 34A
The terminal voltage of the secondary battery 36a is detected (step S1).
3), the comparator 34C compares the terminal voltage of the secondary battery 36a with the reference voltage Va (Step S14).
Then, the CPU 10 determines that the inter-terminal voltage Vb of the secondary battery 36a at the charging completion time Tb is lower than the reference voltage Va, and determines that the secondary battery 36a is defective (step S15). Then, a warning is generated by voice, image, or the like (step S16), and a signal is output to the PS 6A to disable charging of the secondary battery 36a (step S17).

As described above, by using the charging device of this embodiment, the user is immediately notified that the secondary battery 36a has become defective, so that the user can immediately replace the secondary battery 36a. Can be. Therefore, it is possible to prevent a situation in which the movement or capping of the print head becomes unstable, the backup of the memory becomes insufficient, and the time measurement becomes inaccurate.

FIG. 5 is a detailed configuration diagram showing another embodiment of the backup power supply charging device provided in the printer of FIG. As shown in FIG. 5, this charging device includes a power supply (hereinafter, referred to as PS) 60.
A, an RTC 340, and a CPU 100.
Electric double layer capacitor 3 as backup power supply 360
60a and the diode 360b. PS
The switch 60A has a switch 62 and a small power supply (Power Supply) 61 for monitoring the switch 62.
The TC 340 has the same configuration as the RTC 34 of FIG. 2. Even in such a configuration of the charging device, the quality of the electric double-layer capacitor 360a is determined in the same manner as the charging device of FIG. And outputs a signal 100c which disables charging of the electric double layer capacitor 360a.

As described above, the present invention has been described with respect to the specific embodiments. However, the present invention is not limited to these embodiments, and may be applied to other embodiments within the scope of the claims.

For example, when the main power supply is not in the ON state, RT
Although the charging method of the secondary battery for continuing the operation of C has been described, the target to which the secondary battery or the like supplies power is not limited to the RTC, such as a memory backup operation. Furthermore, as long as the charge / discharge can be repeated, and the discharge supplies power for performing a predetermined backup operation when the main power supply is not in the ON state, the backup power supply may be a secondary battery or an electric double layer. Other than a capacitor may be used.

Further, an example in which the printer has a built-in charging device,
That is, the example in which the charging device is configured by the CPU in the printer and the timer and the comparator in the RTC has been described. However, the charging device may be configured as an external unit. Furthermore, although an ink-jet printer that performs capping has been described as an example, other printers such as a laser printer also include a main power supply, and can repeat charging and discharging. As a matter of course, the present invention can be widely applied to any printer having a backup power supply for supplying power for performing the backup operation.

[0044]

As is apparent from the above description, according to the present invention, the necessity of replacement of the backup power supply is notified by the discharge time of the terminal voltage of the backup power supply, so that the user can replace the defective backup power supply. Can be replaced immediately with a working backup power supply. For this reason, the movement and capping of the print head can be performed stably and reliably, the ink can be prevented from drying, etc., and the print head can always be kept in an optimum state, and the memory can be sufficiently backed up. Important data can be reliably stored, and time measurement can be accurately performed so that task schedules and the like can be reliably managed.

Further, the quality of the backup power supply can be immediately determined based on the inter-terminal voltage at the time of completion of the charging of the backup power supply. Therefore, when the backup power supply is defective, it is possible to provide a printer and a printer backup power supply charging device that can avoid unnecessary charge afterwards and save power.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an embodiment of a printer of the present invention.

FIG. 2 is a detailed configuration diagram showing an embodiment of a backup power supply charging device provided in the printer of FIG. 1;

FIG. 3 is a flowchart showing an operation of the charging device shown in FIG.

FIG. 4 is a time chart illustrating an operation of the charging device illustrated in FIG. 2;

FIG. 5 is a detailed configuration diagram showing another embodiment of a charging device for a backup power supply provided in the printer of FIG. 1;

FIG. 6 is a diagram for explaining a first conventional example.

FIG. 7 is a diagram for explaining a second conventional example.

[Explanation of symbols]

 2 Printer controller 4 Print engine 6 Main power supply unit 6A Power supply (PS) 8 RTC unit 10 CPU 12 ROM 14 RAM 16 EEPROM 18 (Mechanical) interface 20 (Host) interface 22 Bus 30 Power cable 32 Power plug 34 RTC 34A Voltage monitoring / Detecting means 34B Timer 34C Comparator 36 Backup power supply 36a Secondary battery 360a Air double layer capacitor

Claims (13)

[Claims] 1. A printer mechanism, a printer controller for controlling the printer mechanism, a main power supply for supplying power to the printer mechanism and the printer controller, and charge / discharge can be repeated. A backup power supply for supplying power for performing a predetermined backup operation to the printer control unit, wherein the printer charges the backup power supply with the power of the main power supply when the main power supply is in an ON state; A printer characterized in that a state of the backup power supply is determined by measuring a time until a voltage between terminals at the time of completion of charging of the backup power supply becomes equal to or lower than a predetermined operating voltage. 2. The printer according to claim 1, further comprising: a voltage monitoring unit that monitors a voltage between terminals of the backup power supply; and a time measurement unit that measures an elapsed time of charging and discharging of the backup power supply. When the voltage between terminals at the time of completion of charging of the power supply becomes equal to or lower than a predetermined operation voltage for a predetermined reference time or less, the status of the backup power supply is determined to be defective and a warning is issued. 3. A printer mechanism, a printer controller for controlling the printer mechanism, a main power supply for supplying power to the printer mechanism and the printer controller, and charge / discharge can be repeated. A backup power supply for supplying power for performing a predetermined backup operation to the printer control unit, wherein the printer charges the backup power supply with the power of the main power supply when the main power supply is in an ON state; A printer, wherein the state of the backup power supply is determined by detecting a voltage between terminals at the time of completion of charging of the backup power supply. 4. The printer according to claim 3, wherein a voltage detector for detecting a voltage between terminals of the backup power supply, and a voltage for comparing the terminal voltage detected by the voltage detector with a predetermined reference voltage. Comparing means for determining that the state of the backup power supply is defective and issuing a warning when the voltage between the terminals at the time of completion of charging the backup power supply becomes equal to or lower than the predetermined reference voltage. Printer. 5. The printer according to claim 2, wherein the warning is issued and charging of the backup power supply is disabled. 6. The printer according to claim 1, wherein said backup power supply comprises a secondary battery. 7. The printer according to claim 1, wherein the backup power supply comprises a capacitor. 8. A printer backup power supply for supplying power to a printer having a main power supply for performing a predetermined backup operation when the main power supply is not in an ON state, wherein charging and discharging can be repeated. In a charging device for a printer backup power supply for supplying power for performing the backup operation by discharging, while monitoring a terminal voltage of the backup power supply,
A real-time clock for measuring an elapsed time of charging / discharging of the backup power supply; and when a voltage between terminals at the time of completion of charging of the backup power supply is lower than a predetermined operating voltage within a predetermined reference time, the state of the backup power supply is defective. A backup power supply for a printer, comprising: a CPU that issues a warning by determining that 9. A printer backup power supply for supplying power to a printer having a main power supply for performing a predetermined backup operation when the main power supply is not in an ON state, wherein charging and discharging can be repeated. In a charging device for a printer backup power supply that supplies power for performing the backup operation by discharging, while detecting a terminal voltage of the backup power supply,
A real-time clock for comparing the detected inter-terminal voltage with a predetermined reference voltage; and when the inter-terminal voltage at the time of completion of charging of the backup power supply falls below a predetermined reference voltage within a predetermined reference time or less, the backup power supply And a CPU for issuing a warning when the status of the printer is bad. 10. The printer backup power supply charging device according to claim 8, wherein the CPU issues the warning and disables the charging of the backup power supply. apparatus. 11. The charging device for a backup power supply for a printer according to claim 8, wherein the backup power supply comprises a secondary battery. 12. The charging device for a backup power source for a printer according to claim 8, wherein the backup power source comprises a capacitor. 13. The charging device for a backup power source for a printer according to claim 8, wherein the charging device is external to the printer.