JPS60109891A - Battery-driven typewriter - Google Patents

Abstract

PURPOSE:To enable a condition wherein a cell voltage is truly lowered to be securely informed, by a method wherein the lowering in the cell voltage is informed only when the cell voltage is lowered to or below a predetermined level in at least a predetermined number of times of printing head moving operations. CONSTITUTION:In a cell-driven typewriter comprising a printing head (c) driven by a cell (a) to print and an informing means (f) for informing the lowering in the cell voltage, a detecting circuit (b) is provided for detecting the condition wherein the cell voltage is lowered to or below a predetermined level, and in the condition wherein a detection signal is outputted from the circuit (b), a counter (d) is operated to count up each time the head (c) is operated to print a character or moved for line feeding or the like. When the counted number reaches a predetermined number, the informing means (f) is operated through the controlling means (e) to inform the lowering of the cell voltage through a liquid crystal display or the like. Accordingly, when the cell voltage is momentarily lowered, the lowering is not informed, and the lowering in the cell voltage is informed only when it is truly lowered.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a typewriter that uses a battery as a driving power source, and particularly relates to a battery-powered typewriter equipped with a notification means for notifying the user that the battery voltage has fallen below a certain level. . In conventional battery-powered typewriters, if the battery voltage drops below a certain level, the typewriter may malfunction, so it is necessary to notify the user of this. This also applies to recording electronic devices such as electronic desktop calculators with printers, and therefore,
Publication No. 0824 proposes that a recording electronic device be equipped with a means for detecting when the power battery has fallen to a level that would cause a malfunction of a recording means such as a printer, and notifying the user of this fact. . In other words, it has been proposed that when the power supply voltage drops below a certain level, a notification sound is emitted for a certain period of time each time a key is pressed, but the battery voltage Even if operations that require high power are performed continuously and the level temporarily drops below a certain level, operations that do not require that much power will continue, or the electronic equipment will go into hibernation. The battery will recover if it is damaged, and it is not necessarily necessary to replace the battery even if the battery voltage once stabilizes and drops below 100Hz. Therefore, if the battery continues to be used as it is, an alarm will be emitted every time the power supply battery temporarily drops below a certain level. This is troublesome, and also has the disadvantage that if the battery voltage drop is reported or not, the user may be concerned that the device has malfunctioned. The same situation applies when a drop in power supply voltage is notified on a visually appealing display means such as a liquid crystal display. OBJECT OF THE INVENTION The present invention has been made against the background of the above-mentioned circumstances, and therefore, an object of the present invention is to solve the problem that the voltage of the power supply battery in a battery-powered typewriter may cause the print head to malfunction. To provide a battery-powered typewriter that can notify the user that the battery voltage has dropped to a certain level, and that does not generate disturbing notification sounds or display when the battery voltage is temporarily constant and has only dropped below 100 Hz. I am here to provide. Structure of the Invention In order to achieve the above-mentioned object, the present invention provides a battery-driven type, as shown in FIG. The writer includes a detection circuit that detects that the voltage of the (al battery) has fallen below a certain level, and (bl) in which the print head performs a predetermined movement operation while an output signal is being generated from the detection circuit. The present invention is characterized by comprising a counter that performs a count amplification every time the print head is activated, and a control means that activates the notification means when the count value of the counter (C1) reaches a predetermined value. The predetermined movement operation means an operation that involves movement of the print head, such as a single character printing operation or a line feed operation.The print head is of a type that prints by dots, such as a thermal head. In some cases, the print head must be moved several steps to print one character.
In this case, it is also possible to define step ``P'' as one movement of the print head and set it as ``C''.In battery-powered typewriters, the battery voltage drops to some extent while the print head is moving. However, when the battery voltage in this decreased state remains constant and reaches below the threshold, a counter is counted up, and when the count value of the counter reaches a predetermined value, a notification means is provided to notify that the battery voltage has decreased. Even if the battery voltage once drops below a certain level, the battery voltage remains constant even if it recovers and the print head performs a predetermined movement operation. If the counter does not decrease below the same value, it is possible to prevent the counter from operating in the same way, and in such a case, it is also possible to actively decrease the number from 1 to 1. In the battery-powered typewriter configured as described above, the notification means does not notify a decrease in battery voltage even if the battery voltage temporarily remains constant and reaches below Hertz, and the notification means does not notify a decrease in battery voltage at least a certain number of times. A decrease in battery voltage is notified only when the battery voltage drops below a certain level during the print head movement operation. Therefore, the user can type without being bothered by the effect of the notification means due to a temporary drop in battery voltage, and if the battery voltage has truly dropped, the user can be sure to know the fact. It can be done. Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIGS. 2 and 3 show external views of a battery-powered portable typewriter that is an embodiment of the present invention. As is clear from FIG. 1, the typewriter of this embodiment is equipped with a keyboard IO at the front.
Alphahet key for O 12. Numeric keys 14. Space par 16. In addition to various keys such as a line feed key 18 that are included in a normal typewriter, arithmetic keys 20 corresponding to addition/subtraction/multiplication/division symbols and equal symbols are arranged. The keyboard 10 is further provided with a liquid crystal display 22, which can display a certain number of characters, symbols, etc. entered manually using the keys. Voltage drop display mark 24
is provided. This voltage drop display mark 24 does not appear on the liquid crystal display 22 when the battery voltage is sufficiently high, but appears when the battery voltage truly drops below a certain level, as will be described later. In addition to these, the keyboard 10 also has a row pinch selection switch 26 in the upper left corner. First mode selection switch 28
and two second mode selection switches 30 are provided. The line pitch selection switch 26 is a switch for selecting the printing line pinch, and the -1 first mode selection switch 28 is a switch for selecting the operating mode of the typewriter.
It is possible to select one of non-print mode, collection print mode, and direct print mode. Here, the non-print 1-mode is a mode in which characters, symbols, and calculation results entered manually are displayed on the liquid crystal display 22 without being printed.
Collection print mode is the key to manually created characters.
This is a mode in which the symbols are corrected while they are displayed on the liquid crystal display 22, and then printed sequentially starting from the overflow from the liquid crystal display 22. Direct print mode is a mode in which characters and symbols manually entered by keys are printed on the liquid crystal display 22. This is a mode in which the information is displayed on the screen and printed at the same time as input. The second mode selection switch 30 is a switch for selecting either a typewriter mode in which the typewriter operates as a normal typewriter or a terminal mode in which the typewriter operates as a data terminal by connecting to an external device. Although the above components are arranged on the top surface of the keyboard 10, a brightness setting dial 32 for setting the brightness of the liquid crystal display 22 and a power switch 34 are further arranged on the right side of the keyboard 10. There is a printing section 36 in the rear part of the keyboard lO as described above.
is set up. The printing section 36 is normally covered with a cover 38 as shown in FIG. 2, but when in use, the cover 38 is opened as shown in FIG. 3. A platen 40 is provided below the cover 38.
A carriage 42 is disposed so as to be movable along the longitudinal direction of the platen 40. Carriage 42 is for printing/＼
The thermal head 44 is supported, guided by a guide rod 46, moved along the longitudinal direction of the platen 40 by a drive device (not shown), and moved around the guide rod 46 by another drive device (not shown). The thermal head 44 is rotated and tilted to press the thermal head 44 against the thermal paper 48 supported by the platen 40. In addition, 50 is a release lever,
It is arranged below the platen 40 and holds the thermal paper 48.
It is provided to move a pair of paper feeding rollers (not shown) of the C feeding basin to a non-operating position where they are separated from each other. The typewriter having the above structure is controlled by a control circuit as shown in FIG. In the figure, 60 is a central processing unit (hereinafter abbreviated as CPU), which includes the keyboard 10, read-only memory 62 (hereinafter abbreviated as ROM), and random access memory 64 (hereinafter abbreviated as RAM). ), a printing mechanism driver interface 66, a display controller 68, an external ink face driver receiver 70, and the like are connected. A printing mechanism 72 is connected to the printing mechanism driver interface 66, and the liquid crystal display 22 is connected to the display controller 68. Further, an external ink face 74 is connected to the external ink face driver receiver 70 so that data can be exchanged between the present typewriter and an external device such as a typewriter of the same type or a personal computer. The printing mechanism 72 is connected to the platen 40 and the carriage 4.
2, a driving device for driving them, and a thermal head 44. The display controller 68 also has a built-in display buffer memory with the same number of digits as the liquid crystal display 22, and the CPU 60 handles each character/symbol input from the keyboard 10, such as alpha vents, numbers, spaces, arithmetic symbols, and other symbols. The display controller 6 sequentially stores code data corresponding to each printing function such as line feed function 1 paper feed function in the display buffer memory, and reads pattern data corresponding to these code data from the ROM 62.
Supply to 8. Further, the RAM 64 includes a print buffer memory for a certain number of characters, and the printing mechanism driver interface 66 transfers the printing to the printing mechanism 72 according to the pattern data read out from the ROM 62 by the CPU 60 based on the code data stored in the sofa memory. In addition to driving the thermal head 44, it also controls the motors and the like for driving the carriage 42 and platen 40. Further, the ROM 62 stores a program for controlling the overall operation of the typewriter. A text memory 75 is provided in the RAM 64,
It is possible to store a certain amount of character/symbol data and function data including print control data. RAM6
4 is further provided with a counter register 76 whose operation will be described in detail later, and a flag register 78 which stores a weak hatch refill flag. The counter register 76 consists of 1 byte. The type-like configured as described above can operate in a direct print mode in which normal printing is performed as described above, as well as a non-print mode and a collection print mode. It is possible to perform calculations and print the calculation formula and calculation results on the thermal paper 48, but the operation itself is not directly related to the understanding of the present invention, so a description thereof will be omitted. , only operations related to displaying a decrease in battery voltage will be explained based on the flowchart of FIG. When the power switch 34 is turned on, execution of the program stored in the ROM 62 is started, and step S
1, initial settings are performed. After that, the thermal head 44 returns to its original position (
After that, the mechanism B11 is initialized, such as being moved to the left margin position, and various buffer memories, work memories, etc. are cleared, and at the same time, the counter register 7G, flag register 78, etc. are cleared. will also be held. When the initial setting is completed, a scan is performed in steps s2 and S3 to determine whether or not a key input such as °ctI is performed, and if there is a key input, the key input data is checked in step S4. It is displayed on the liquid crystal display 22. Next, in step S5, it is determined whether the weak battery flag is ON or not, but since this flag is OFF in the initial stage, the determination result is NO, and the program execution is not completed. The process moves to step S6, and the battery voltage drop display is turned off.
be made into That is, the voltage drop display mark 24 provided on the liquid crystal display 22 is not visible. Subsequently, step S7 is executed, and while the carriage 42 is moved one step at a time along the longitudinal direction of the platen 40, a predetermined heating element of the thermal head 44 is made to generate heat, and one character is printed. That is, when the thermal head 44 prints one character in 5 steps, the thermal head 44 prints one character in 5 steps.
The printing of one character is completed when the printing of one character is moved by 5 steps. Immediately after the printing of one character is completed, step S8 is executed, and it is determined whether or not the weak batch reswitch is in the ON state. Ru. carriage 42
The battery voltage decreases to some extent when the printer moves and the thermal head 44 is driven, but even immediately after printing one character, the battery voltage is almost in this reduced state. Even if you check the battery voltage immediately after printing is completed, you can obtain the same result as checking the battery voltage during a printing operation that involves movement of the thermal head 44. This provides the advantage that it is not necessary to execute step S8 during the control of 66 or the like. Note that the weak battery switch can be configured with a transistor, for example. Apply a voltage corresponding to the battery voltage to the base of the transistor,
When this voltage remains constant and drops below Hertz, the transistor becomes conductive and the weak hatch switch is said to be in the ON state. If the determination result in step S8 is NO, the execution of the program moves to step S9, where it is determined whether the counter can count down, that is, even if the contents of the counter register 76 are set to (1) or decreased.

A determination is made as to whether or not the value becomes smaller than [0]. If the contents of the counter register 76 are [1] or more, the judgment result is YE.
S and the countdown in step s19 is executed, but at this stage the counter register 76 is in the state that was reset in the initial setting of step S1, so the contents, that is, the count value of the counter are

Since it is [0], step S1O is not executed, and the program execution moves to step S11. Step 31
In step 1, it is determined whether the count value is greater than a certain value. In this embodiment, the counter register 76 is composed of 1 byte as described above, and in step Sll it is determined whether the most significant digit has become 1. , the constant value is (
127). The judgment result is N at this stage.
Since it is O, step S12 is executed, but
Since the weak battery flag has already been set to the OFF state in the initial setting of step S1, the program execution returns to step S2 while remaining in that state. Hereinafter, each time the key is pressed, the same operation is repeated and printing is performed, but as a result, the battery voltage drops by 2, and the determination result in step S8 may eventually become YES. It's coming. In this case, step S13 is executed and it is determined whether the counter register 76 can be used for count amplification. However, when the weak batch switch is turned ON for the first time, the count value of the counter is

Since it is [0] and it is possible to count up, the determination result is YE and S, and the process proceeds to step S14.
A count-up is performed at . Then step S
ll is executed, but the judgment result is still NO.
Therefore, the program execution returns to step S2 via step S12. Step S immediately after the printing operation based on the subsequent key manual power
If the determination result in step 8 is YES again, steps 513 and S14 are executed, but just because the weak battery switch was turned on immediately after the previous printing operation does not necessarily mean that it will be turned on immediately after the next printing operation. Since it is not always the case, if it is OFF, step S8
The judgment result is NO, steps S9 and SIO are executed, and the contents of the counter register 76 are decreased by (13). The Wee Ubanoteli switch is turned on.
It is checked whether it is in the ON state or OFF state.
If it is in the state, the contents of the counter register 76 are [l]
It is increased, and if it is in the OFF state, it is decreased by [1]. Therefore, if the weak battery switch continues to be ON every time a printing operation is performed, the contents of the counter register 76 will eventually reach (12B).
The result of the determination in step Sll is YES, step S15 is executed, and the weak battery flag is set to O.
It is considered N. Zunawaji, the contents of the flag register 78 are [
1]. That is, when the key is pressed manually next time, the determination result in step S5 becomes YES, and the battery voltage drop display is turned on in step 316. In other words, a voltage drop indicator mark 24 provided on the liquid crystal display 22 is displayed. The fact that this voltage drop display mark 24 is displayed means that the weak battery switch was in the ON state during the printing operation for at least 128 characters.Actually, a countdown is also performed, so there are considerably more than 128 characters. When printing characters, the weak hatch switch is set to O.
The battery voltage has dropped to a level where there is a real risk of erroneous printing, and it is therefore necessary to replace the battery. However, even in this state, it is possible to use the typewriter in a non-print mode that does not involve printing operations. If the typewriter is used without replacing the battery even after the battery voltage drop is displayed, the content value of the counter register 76 will reach the maximum value (2
55), when the count amplification is performed further, the content value of the counter register 76 is changed again.

Since the voltage returns to [0] and the voltage drop display mark 24 disappears, in this case, the determination result in step S13 becomes NO, and the count amplification in step S14 is not performed. In the embodiment detailed above, the battery voltage drop display is not performed while the count value of the counter is below a certain value,
This is done when a certain value is exceeded. Therefore, in this case, after the count value once exceeds a certain value, if the battery voltage becomes constant and recovers to a level higher than 1, the voltage drop display mark 24 will appear or disappear. If the count value for displaying the voltage drop is set high enough, this problem will not occur, but in order to more reliably prevent this kind of situation from occurring, the flowchart shown in Figure 6 can be used. The represented program may be stored in the ROM 62. The flowchart in FIG. 6 is similar to the flowchart shown in FIG. 5 up to the countdown in step SIO and the count amplifier in step S14, but the steps after these are different. That is, in step 317, it is determined whether the Karun 1-value is less than or equal to the first reference value (n3), and if the result of the determination is YES, the weak battery flag is turned OFF in step Sj8, and , step S19
In step S20, it is determined whether the count value is equal to the second reference value (N), and if the result of the determination is YES, the weak battery flag is turned ON in step S20. . Note that step S17
If the result of the determination in step S19 is NO, the program execution returns to step S2. As shown in FIG. 7, the first reference value (n) is made smaller than the second reference value (N) by a certain value. For example, the second reference value (N) is (128), and the first reference value (n) is [
64]. Therefore, the weak battery flag that is turned ON when the Karun 1 value reaches the second reference value (N) will not be turned OFF unless the count value falls to the first reference value (n'), and the weak battery flag will not be turned OFF until the count value falls to the first reference value (n'). Step S is performed by turning on the hatch flag.
After the battery voltage drop display is performed once at i6, the display will not be erased even if the battery voltage fluctuates slightly, and a stable battery voltage drop display will be performed. Although two embodiments of the present invention have been described above, these are literally illustrative, and the present invention can be implemented in other embodiments. For example, the means for notifying battery voltage drop is not limited to using a part of the liquid crystal display 22 as in each of the above embodiments, but a separate pressure drop indicator lamp may be provided. Also, the notification means is not necessarily limited to one that appeals to the visual sense, but it is also possible to emit a notification sound to appeal to the auditory sense. Furthermore, the specific program for notifying the voltage drop is not limited to that of the embodiment described above, and furthermore, the mechanism and control device of the typewriter are also limited to those of the embodiment described above. Rather, the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. FIG. 2 is an external perspective view of a battery-powered portable typewriter according to an embodiment of the present invention, and FIG. 3 is a perspective view partially showing the state in which the typewriter is used. FIG. 4 is a block diagram showing a control device for the typewriter. FIG. 5 is a flowchart 1 showing a program stored in the ROM of FIG. FIG. 6 is a diagram partially showing flowchart 1 of a program in another embodiment of the present invention. Figure 7 shows the O of the Weekha 7 Terriflag according to the flowchart of Figure 6.
FIG. 3 is an explanatory diagram showing N/OFF control. lO: Keyboard 1 22: Liquid crystal display 24: Voltage drop display mark 3 G: r41 character section 42: Keyboard nozzle 44: Thermal head 60: Central processing unit (C
P U) 62: Read-only memory (ROM, ) 64: Random access memory (RAM) 68: Display controller 76: Counter register 78 Two-flag register Applicant Brother Industries, Ltd. Agent Patent attorney Nori Kanbe Kazu 1-” 1゛](,1 (2 idiots) blaming ,,11 N ′-・

Claims (1)

[Scope of Claims] In a battery-powered typewriter having a printing gutter that is driven by a battery and has a notification means for notifying a drop in voltage of the battery, detecting that the battery voltage has fallen below a certain level. a detection circuit that performs a count-a-knob each time the print head performs a predetermined movement operation in a state in which an output signal is emitted from the detection circuit; A battery-powered typewriter characterized by comprising: control means for activating the notification means when a predetermined value is reached.