JP2002086848A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer capable of reducing a number of times of replacing or charging of a battery which may be burdensome to a user and of improving a working efficiency. SOLUTION: A low battery level is corrected corresponding to a value in a predetermined condition which may cause variation in energy to be applied to an individual driving element. As the battery can be used to an assured maximum extent whereby operations (printing) in the present use environment can be executed, it is possible to increase a number of sheets of paper to be printed by a battery charged by one time and to reduce the number of times of working for replacing or charging the battery which may be burdensome to a user so that the working efficiency can be improved. As the number of times of charging is reduced, the life of the battery can be extended.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer which is driven by power supply from a battery and applies energy to individual driving elements to print on paper.

[0002]

2. Description of the Related Art Conventionally, in a thermal printer which is driven by power supply from a battery and applies energy to a heating element of a thermal head which is an individual driving element to print on paper, the voltage level of the battery is at a certain level. When the following is detected, the operation (printing) is disabled by disabling the operation (printing) as a low battery error.

Here, as for a specific level (low battery level) used for determining a low battery error, a predetermined condition that causes a change in the amount of energy applied to the heating element requires the most amount of energy applied to the heating element. Assuming that the operating environment conditions are such that
The operation (printing) can be guaranteed even under the use environment conditions. In detail, the test is performed at the values of the operating environment conditions that require the most amount of energy applied to the heating element (the lowest temperature of the operation guarantee range, the maximum print density fine adjustment value, the maximum printing rate within the print guarantee range, etc.). As a result of the repetition, the minimum usable battery voltage level is determined as the low battery level.

[0004]

However, when the low battery level is determined by the above-described method, the following problems occur.

For example, even when the voltage level of the battery has reached the low battery level, the value of the predetermined condition that causes the amount of energy applied to the heating element to be the most required is the amount of energy applied to the heating element. If the value is not the value of the use environment condition, the printer cannot be operated (printed) even though the voltage level is still operable (printed) as the printer. If the printer goes into a low battery error state even though the voltage level is still operable (printing) in this way, measures such as replacing the battery and charging the battery must be taken frequently. Therefore, it takes extra time and effort for the user, which causes problems such as a decrease in work efficiency. Also,
There is also a problem that the life of the battery is shortened by frequently repeating charging / discharging.

Further, the number of sheets that can be printed by the printer using the battery is calculated by assuming the use environment conditions that require the most amount of energy applied to the heating elements as described above. This is different from the number of printable sheets under environmental conditions.

The problem described above is not limited to a thermal printer that applies energy to a heating element, which is an individual driving element, to print on paper, but also causes vibration by applying a voltage to a piezoelectric element (piezo element), which is an individual driving element. Controls the amount of ink sublimated by the amount of heat or the piezo-type printer that ejects ink by applying heat, a thermal ink-jet printer that ejects ink by generating air bubbles by applying heat to the ink by heating resistors that are individual drive elements This also occurs in sublimation type printers and the like.

SUMMARY OF THE INVENTION An object of the present invention is to reduce the number of user-requiring operations of battery replacement / charging,
An object of the present invention is to provide a printer capable of improving work efficiency.

[0009]

According to the first aspect of the present invention,
In a printer which is driven by power supply from a battery and applies energy to the individual drive elements to print on paper, the printer controls the power of the battery according to a value of a predetermined condition which causes a variation in the amount of energy applied to the individual drive elements. There is provided a low battery level correction means for correcting a low battery level which is a minimum usable voltage level.

Therefore, the low battery level is corrected in accordance with the value of the predetermined condition that causes the amount of energy applied to the individual drive element to fluctuate. This makes it possible to use the battery to the maximum extent that operation (printing) can be guaranteed under the current operating environment conditions, thereby increasing the number of printable sheets per battery charge. At the same time, it is possible to reduce the number of operations of replacing and charging the battery which bother the user.
Work efficiency can be improved. Also, by reducing the number of times of charging, the life of the battery can be extended.

According to a second aspect of the present invention, in a printer which is driven by power supply from a battery and applies power to the individual driving elements to print on paper, the amount of power applied to the individual driving elements is varied. A low battery level correction unit that corrects a low battery level that is a minimum usable voltage level of the battery according to a value of a predetermined condition.

Therefore, the low battery level is corrected according to the value of the predetermined condition that causes the amount of power applied to the individual drive element to fluctuate. This makes it possible to use the battery to the maximum extent that operation (printing) can be guaranteed under the current operating environment conditions, thereby increasing the number of printable sheets per battery charge. In addition, it is possible to reduce the number of times of the user's troublesome work of replacing / charging the battery, thereby improving the work efficiency. Also, by reducing the number of times of charging, the life of the battery can be extended.

[0013] The invention according to claim 3 is the invention according to claim 1 or 2.
In the printer described above, a printable sheet number calculating unit that calculates the number of sheets that can be printed from a current voltage level to the low battery level corrected by the low battery level correction unit, and the printable sheet number calculation unit And a notifying unit for notifying the calculated number of printable sheets.

Accordingly, the number of printable sheets is notified from the current voltage level to the corrected low battery level, so that the number of printable sheets can be ascertained. It is possible to obtain.

According to a fourth aspect of the present invention, in the printer according to the third aspect, the printable sheet number notifying means transmits the printable sheet number calculated by the printable sheet number calculating means to an external device. .

Therefore, by transmitting the number of printable sheets to the external device from the current voltage level to the corrected low battery level, the number of printable sheets can be grasped by the external device. Therefore, it is possible to obtain an easy-to-use printer.

According to a fifth aspect of the present invention, in the printer according to the third aspect, the printable sheet number notifying means prints the printable sheet number calculated by the printable sheet number calculating means on the sheet.

Therefore, since the number of printable sheets is printed on the paper from the current voltage level to the corrected low battery level, the number of printable sheets can be ascertained, so that it is easy to use. It becomes possible to obtain a printer.

The invention according to claim 6 is the invention according to claims 1 to 5
The printer according to any one of the above, is a small portable printer that is carried and used.

Therefore, by correcting the low battery level in accordance with the value of the predetermined condition that causes the amount of energy applied to the individual drive element to vary, even a small portable printer in which the use environment changes rapidly, In each case, it is possible to obtain a voltage level that defines an appropriate low battery level.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. The printer according to the present embodiment is applied to a small portable printer that performs printing using a thermal head and is used by carrying.

FIG. 1 is a perspective view showing the appearance of a portable printer 1 according to the present embodiment. The portable printer 1 includes, in a main body case 2, a paper storage unit (not shown) for storing roll paper around which long paper (thermal label paper) is wound, and opens and closes the paper storage unit. The cover 3 is provided on the front of the main body case 2. Although not particularly shown, when the cover 3 is closed, the paper transporting the paper drawn from the roll paper stored in the paper storage unit between the cover 3 and the main body case 2 A path is formed.

A thermal head 16 (see FIG. 2) for printing on paper conveyed in the paper conveyance path is mounted on the surface of the opening / closing cover 3 on the paper storage section side. A platen (not shown) that presses against the thermal head 16 across the paper transport path with the opening / closing cover 3 closed is rotatably mounted in the main body case 2. Further, the opening / closing cover 3 is also provided with a paper discharge port 4 from which the paper printed by the thermal head 16 is discharged.

The portable printer 1 includes a battery mounting portion 5 and an external power supply connector (not shown), and a battery 22 (see FIG. 2) mounted on the battery mounting portion 5.
External power supply 2 connected to the external power supply connector
1 (see FIG. 2).

Next, the electrical connection of each part built in the portable printer 1 will be described with reference to FIG. As shown in FIG. 2, the portable printer 1 executes various arithmetic processes to centrally control each unit (Centra).
l Processing Unit) 6, which has a flash ROM (Read Only Memory) 7 and an SRA
An M (Static Random Access Memory) 8 is connected by a bus line. Various control programs are stored in the flash ROM 7, and the CPU 6 drives each unit according to the control programs. Also, SRAM
The predetermined area 8 is used as a print buffer or various counter areas.

The CPU 6 has an LED (Light Emit).
ting Diode 9, various switches 10, a label sensor 11 for detecting whether there is a sheet at a printable position, a motor driver 12, a thermal head controller 13, and a selector 14 are connected to a bus. The LED 9 is a light emitting element for display. Although only one LED 9 is shown in FIG. 2, a plurality of LEDs 9 are actually provided for error display, low battery display, display during printing, and the like. The various switches 10 include a power switch, a feed switch, and a thermal head open switch.

The motor driver 12 connected to the CPU 6
Is connected to a pulse motor 15 which is a driving source for rotating the platen to feed a sheet.

In the thermal head controller 13 connected to the CPU 6, a large number of heating resistors (individual driving elements) are arranged in a line in the paper width direction, and these heating resistors are applied by applying energy. A thermal head 16 for selectively driving and printing on paper is connected.

Further, the selector 1 connected to the CPU 6
4 includes an infrared sensor controller 18 to which an infrared sensor 17 is connected, and an RF module 19 for wireless communication.
And an I / F 20 used for wired communication with a host device such as a personal computer as an external device, and one of these three is used by selection by the selector 14.

Therefore, in the printing process of the portable printer 1, first, when print data is received from either the infrared sensor 17, the RF module 19, or the I / F 20, the print data is temporarily stored in the SRAM 8, The data is developed as image data assigned to each line in a print buffer provided in the SRAM 8.

In addition, the portable printer 1 has
A thermal head temperature measurement sensor 24 for measuring the temperature of the thermal head 16 and an outside air temperature measurement sensor 25 for measuring the temperature of the outside air are provided. The thermal head temperature measurement sensor 24 and the outside air temperature measurement sensor 25 It is connected to CPU6. The reason why the outside air temperature and the temperature of the thermal head 16 are measured in this way is to control the amount of energy applied to the heating resistor provided in the thermal head 16 with reference to the outside air temperature and the temperature of the thermal head 16.

As described above, the portable printer 1 is provided with the external power supply 21 and the battery 22 as power supply sources, and either one of them is selectively used. In the present embodiment, the voltage of the battery 22 is set to approximately 8.4 V to 7.1 V, and the voltage of the external power supply 21 is set to approximately 9 V (± 0.4 V).

A voltage detecting circuit 23 for measuring a voltage supplied to the power supply path is also connected to the CPU 6 via a bus. In the present embodiment, the reference value for the determination is 8.5 V by setting the battery 22 to 8.4 V even when fully charged and the external power supply 21 to at least 8.6 V.
By doing so, it is possible to determine whether the voltage value measured by the voltage detection circuit 23 is the voltage value of the power supplied from the external power supply 21 or the voltage value of the power supplied from the battery 22.

Next, the control program stored in the flash ROM 7 built in the portable printer 1
The function executed by the PU 6 will be described. In the present embodiment, a description of the same processing as that performed by the conventional portable printer will be omitted.

FIG. 3 is a flowchart schematically showing the flow of the print control, and FIG. 4 is a flowchart schematically showing the flow of the low battery level correction process. As shown in FIG. 3, when the power is turned on by operating the power switch, first, a predetermined initialization process is executed (step S1), and then a low battery level correction process (step S1).
Perform 2).

Here, the low battery level correction processing in step S2 will be described in detail with reference to FIG. This low battery level correction process is generally performed as follows.
The low battery level (set to “7.10 V” in the present embodiment) determined at the time of the initial setting is set to the current use environment conditions of the portable printer 1 (in the present embodiment, each of the thermal heads 16). The outside air temperature, the temperature of the thermal head 16, the print density fine adjustment value, the average resistance value of each heating resistor of the thermal head 16, and the number of black dots relative to the number of dots per line, which cause the amount of energy applied to the heating resistor to vary Is corrected in accordance with the value of (printing ratio) which is the ratio of In this embodiment, the reference value of each use environment condition when the low battery level is “7.10 V” is “2” in the outside air temperature.
5 ° C. ”, the thermal head temperature“ 25 ° C. ”, the print density fine adjustment value“ ± 0 ”, the average resistance value of each heating resistor of the thermal head 16“ 160Ω ”, and the printing rate“ 10% ”.

As shown in FIG. 4, in the low battery level correction processing, first, in step S21, the outside air temperature is measured by the outside air temperature measuring sensor 25, and the low battery level is corrected according to the measured outside air temperature. Specifically, when the outside air temperature measured by the outside air temperature measurement sensor 25 is “30 ° C.”, the reference outside air temperature “25”
° C ”and the current outside air temperature“ 30 ° C ”, the following equation based on the difference: 7.1 + {(25-30) / 100} = 7.05 (V) The low battery level “7.05 (V)” is calculated.

In the following step S22, the temperature of the thermal head 16 is measured by the thermal head temperature measuring sensor 24, and the low battery level is corrected according to the measured temperature of the thermal head 16. Specifically, when the temperature of the thermal head 16 measured by the thermal head temperature measurement sensor 24 is “35 ° C.”, the reference thermal head temperature “25 ° C.” and the current thermal head temperature “35 ° C.” And the following equation based on the difference between the temperature and the temperature of the thermal head 16: 7.05 + {(25−35) / 100} = 6.95 (V) Battery level "6.9
5 (V) "is calculated.

In the following step S23, the current print density fine adjustment value is obtained, and the low battery level is corrected according to the obtained print density fine adjustment value. In particular,
If the acquired print density fine adjustment value is “+3”, the following equation based on the difference between the reference print density fine adjustment value “± 0” and the current print density fine adjustment value “+3”: 6.95+ { (0 + 3) / 50} = 7.01 (V), the low battery level “7.01 (V) corrected according to the fluctuation of the outside air temperature, the fluctuation of the temperature of the thermal head 16 and the fluctuation of the print density fine adjustment value. ) "Is calculated.

In the following step S24, the current average resistance value of each heating resistor of the thermal head 16 is obtained, and the low battery level is set in accordance with the obtained average resistance value of each heating resistor of the thermal head 16. to correct.
Specifically, when the acquired average resistance value of each heating resistor of the thermal head 16 is “150Ω”, the reference average resistance value is “160Ω” and the current average resistance value is “160Ω”.
The following equation based on the difference from Ω ″: 7.01 − {(160−150) / 200} = 6.95
(V), the low-battery level corrected according to the fluctuation of the outside air temperature, the fluctuation of the temperature of the thermal head 16, the fluctuation of the print density fine adjustment value, and the fluctuation of the average resistance value of each heating resistor of the thermal head 16. 6.95 (V) "is calculated.

In the following step S25, the current printing rate is obtained, and the low battery level is corrected according to the obtained printing rate. Specifically, when the acquired printing rate is “15%”, the reference printing rate “10%”
6.95 − {(10−15) / 100} = 7.00 (V) based on the difference between the current printing rate “15%” and the current printing rate “15%”: , The low battery level “7.00 (V)” corrected in accordance with the fluctuation of the print density, the fluctuation of the average resistance value of each heating resistor of the thermal head 16 and the fluctuation of the printing rate. You.

Through the above steps S21 to S25, various element conditions are calculated with respect to the original reference low battery level, and a low battery level suitable for use environment conditions is calculated. Here, the function of the battery level correction means is executed.

When the low battery level correction process in step S2 is completed, the process proceeds to step S3, where the voltage of the battery 22 is read by the voltage detection circuit 23.

In the following step S4, step S
The low battery level calculated in the low battery level correction process of No. 2 is compared with the voltage of the battery 22 read in step S3.

If the voltage of the battery 22 read in step S3 is higher than the low battery level calculated in the low battery level correction process,
If the voltage has not reached the low battery level (N in step S4), the process waits for a print request (step S5), a self-diagnosis request (step S6), or a printer status request (step S7) from the host machine.

When the print data is transferred from the host machine or the like and there is a print request (step S5), the low battery level correction process is executed again (step S8). Since the low battery level correction processing here is the same processing as the low battery level correction processing in step S2, description thereof will be omitted.

Thereafter, the process proceeds to step S9, where the voltage of the battery 22 is read by the voltage detection circuit 23.

In the following step S10, the low battery level calculated in the low battery level correction processing in step S8 and the battery 22 read in step S9 are read.
And the voltage of.

If the voltage of the battery 22 read in step S9 is higher than the low battery level calculated in the low battery level correction process,
If the voltage has not reached the low battery level (N in step S10), the printing process (step S11) is performed based on the printing data transferred from the host device or the like, and then the process returns to step S5.

On the other hand, if the voltage of the battery 22 has reached the low battery level (Y in step S4, Y in step S10), a low battery process is executed (step S12), and the process ends. As the low battery processing, for example, there is processing such as turning on the LED 9 for low battery display.

When there is a self-diagnosis request (Y in step S6), the current voltage level is changed to step S2.
The number of printable sheets up to the low battery level calculated in the low battery level correction process is calculated based on, for example, the power consumption per printing (step S
13: printable number calculation means), based on the printable number and the value of each condition used in the low battery level correction process in step S2, creates self-diagnosis result print data (step S14). The self-diagnosis request is requested by operating the feed switch together with the power switch when the power is turned on, for example.

After executing the self-diagnosis result printing process (step S15: printable number notification means) based on the self-diagnosis result print data, the process returns to step S5.
Here, FIG. 5 is a plan view showing an example of a state where the self-diagnosis result is printed. As shown in FIG. 5, as a result of the self-diagnosis, in addition to the outside air temperature a, the thermal head temperature b, the voltage c of the battery 22, and the print density fine adjustment value d, the low battery calculated in the low battery level correction processing in step S2. The level e and the printable number f calculated in step S13 are printed.

When a printer status request signal is received from the host machine via the I / F 20 (Y in step S7), the low battery level correction process is executed again (step S16). Since the low battery level correction processing here is the same processing as the low battery level correction processing in step S2, description thereof will be omitted.

Thereafter, the step S is started from the current voltage level.
The number of printable sheets up to the low battery level calculated in the low battery level correction process 2 is calculated based on, for example, the power consumption per sheet (step S17: printable sheet number calculating means), and the printable sheet number is calculated. The transmission data is created based on the low battery level and the like calculated in the low battery level correction processing in step S16 (step S18), and the transmission processing to the host machine is executed (step S19: printable sheet number notifying means), and again. It returns to step S5.

The low-battery level is corrected according to the value of a predetermined condition that causes the amount of energy applied to each heating resistor of the thermal head 16 to fluctuate. (Printing) can be used to the maximum extent that can be guaranteed, so that the number of printable sheets per charge of the battery can be increased, and the battery replacement / charging operation is troublesome for the user. The number of times can be reduced, and work efficiency can be improved. In addition, the life of the battery 22 can be extended by reducing the number of times of charging.

In this embodiment, the portable printer 1 using the thermal head 16 is applied as a printer. However, the present invention is not limited to this. For example, a voltage is applied to a piezoelectric element (piezo element) which is an individual driving element. In addition, a piezo-type ink jet printer that ejects ink by vibrating it, a thermal ink jet printer that ejects ink by generating air bubbles by applying heat to the ink by individual driving elements (heating resistors),
A sublimation printer or the like that controls the amount of sublimated ink by the amount of heat may be applied.

The method of changing the low battery level is not limited to the above embodiment.
Various methods such as storing a correction value for each factor in advance and correcting the low battery level with the stored correction value can be applied.

[0058]

According to the first aspect of the present invention, in a printer which is driven by power supply from a battery and applies energy to the individual driving elements to print on paper, the amount of energy applied to the individual driving elements varies. Low battery level correction means for correcting a low battery level, which is a minimum usable voltage level of the battery, according to a value of a predetermined condition which causes the energy to be applied to the individual driving element; By correcting the low battery level according to the value of a predetermined condition, the battery can be used to the maximum extent that the operation (printing) can be guaranteed under the current use environment condition, so that the battery charge once. It is possible to increase the number of printable sheets per unit, and to bother the user to replace / recharge the battery. It is possible to reduce the number of work, thereby improving the working efficiency. Further, the life of the battery can be extended by reducing the number of times of charging.

According to the second aspect of the present invention, in a printer which is driven by power supply from a battery and applies power to the individual drive elements to print on paper, a factor which varies the amount of power applied to the individual drive elements Low battery level correction means for correcting the low battery level, which is the minimum usable voltage level of the battery, according to the value of the predetermined condition, which is a factor that causes the amount of energy applied to the individual drive element to fluctuate. By correcting the low battery level according to the value of the condition, it is possible to use the battery to the maximum extent that the operation (printing) can be guaranteed under the current usage environment conditions, so the The number of sheets that can be printed can be increased, and the number of user-requiring operations such as battery replacement / charging is reduced. Succoth can, thereby improving the working efficiency. Also, by reducing the number of charging times,
Battery life can also be extended.

According to the third aspect of the present invention, in the printer according to the second aspect, the number of printable sheets from the current voltage level to the low battery level corrected by the low battery level correction means is determined. A printable sheet number calculating means for calculating, and a printable sheet number notifying means for notifying of the printable sheet number calculated by the printable sheet number calculating means, wherein the current battery level is changed to a corrected low battery level. By notifying the number of printable sheets up to this, the number of printable sheets can be ascertained, so that a user-friendly printer can be obtained.

According to a fourth aspect of the present invention, in the printer according to the third aspect, the printable sheet number notifying means transmits the printable sheet number calculated by the printable sheet number calculating means to an external device. As a result, the number of sheets that can be printed from the current voltage level to the corrected low battery level can be transmitted to the external device, and the number of printable sheets can be ascertained by the external device. You can get a good printer.

According to a fifth aspect of the present invention, in the printer according to the third aspect, the printable sheet number notifying means includes:
By printing the number of printable sheets calculated by the printable sheet number calculating means on the sheet, the number of printable sheets from the current voltage level to the corrected low battery level is printed on the sheet. Since the number of printable sheets can be ascertained, an easy-to-use printer can be obtained.

According to the sixth aspect of the present invention, in the printer according to any one of the first to fifth aspects, since the printer is a small portable printer to be carried and used,
By correcting the low battery level according to the value of a predetermined condition that causes the amount of energy applied to the individual drive element to fluctuate, even in a small portable printer whose usage environment changes rapidly, an appropriate low A voltage level that defines the battery level can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an appearance of a portable printer according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an electrical connection of each unit built in the portable printer.

FIG. 3 is a flowchart schematically showing a flow of print control.

FIG. 4 is a flowchart schematically showing a flow of a low battery level correction process.

FIG. 5 is a plan view showing an example of a state where a self-diagnosis result is printed.

[Explanation of symbols]

 1 Printer 22 Battery

Claims (6)

[Claims] 1. A printer which is driven by power supply from a battery and applies energy to an individual drive element to print on paper, wherein a value of a predetermined condition which causes a change in an amount of energy applied to the individual drive element is determined. A low-battery level correction unit for correcting a low-battery level, which is a minimum usable voltage level of the battery. 2. A printer which is driven by power supply from a battery and applies power to an individual driving element to print on a sheet. A low-battery level correction unit for correcting a low-battery level, which is a minimum usable voltage level of the battery. 3. A printable sheet number calculating means for calculating a printable sheet number from a current voltage level to the low battery level corrected by the low battery level correction means, and a printable sheet number calculating means. 3. The printer according to claim 1, further comprising: a printable sheet number notifying unit that notifies the calculated printable sheet number. 4. The printer according to claim 3, wherein said printable sheet number notification means transmits the number of printable sheets calculated by said printable sheet number calculation means to an external device. 5. The printer according to claim 3, wherein the printable sheet number notifying means prints the printable sheet number calculated by the printable sheet number calculating means on the sheet. 6. The printer according to claim 1, wherein the printer is a small-sized portable printer to be carried and used.