JP6439582B2 - Handy mobile printer and its program - Google Patents

Description

  The present invention relates to a handy mobile printer that includes an ink jet head having nozzles and discharges ink from nozzles according to image data while being operated on a paper surface by a human hand, and a computer program that controls the handy mobile printer.

The printer is a well-known printing device, and there are various printers with different writing methods such as an ink jet printer, a laser printer, a thermal printer, and a dot impact printer. The present invention relates to an inkjet printer among them.
An inkjet printer is a device that forms a desired image such as a character or a picture by applying ink to paper as a printing medium. In general, the ink is applied by a print head assembled on a guide rail accurately installed in a certain direction (main scanning direction).

That is, the print head is moved vertically below the print head by a transport system that transports the paper that is the print medium in the direction perpendicular to the guide rail (sub-scanning direction). Is reciprocated along the guide rail. During this operation, ink is ejected at the same timing, and ink is applied onto the paper.
When the ink application by the reciprocating motion of the print head is completed, the paper is transported by a predetermined amount in the sub-scanning direction, the position is held (still), and the ink is applied while the print head is reciprocating. By repeating this operation, a desired image is formed.

Recently, due to the downsizing of notebook personal computers (PCs) and the rapid spread of smart devices, downsizing and portability of printers have become one of the great demands.
As a portable printer, a “mobile printer” that has been downsized to a portable size has already been commercialized. The form of the printer is large enough to fit into a business bag while having the functions of a normal general printer such as a desktop serial printer.
However, as described above, a guide rail for fixing the print head and a paper transport system are required, and it is necessary to pass a predetermined standard paper.

Therefore, in response to the demand for further miniaturization and portability, a “handy mobile printer” has been developed that applies ink while scanning the printer with the hand of a person with a mechanism that eliminates the paper transport system.
Several handy mobile printers have already been commercialized, and examples include the following.

-Printer equipped with a position detection function in one direction (for example, the X-axis direction) and scanning only in one direction for printing (consent with printing or image formation)-Position detection function in two directions (for example, the X / Y axis direction) A printer that scans and prints only in two directions ・ A printer that has a position detection function in three directions (for example, X / Y / R axis, R: rotation) and can scan and print freely on a plane ( (However, there is no product currently on sale)

In any case, being able to accurately detect the position of the handy mobile printer itself is a problem when printing an image larger than the print head or when printing with high image quality.
A printer that freely scans and prints on a plane needs to relatively detect positions in three directions (X / Y / R axes) on the plane of the printer itself with respect to paper. As such a method, for example, a method of detecting a position by installing a plurality of optical sensors such as those used in a PC pointing device is known.

The position detection function of an optical sensor used in a PC pointing device acquires (samples) several mm square images several thousand times per second. Then, the relative degree of movement (ΔX, ΔY) in two directions is output by comparing the difference in the images (frames) at a time.
If a plurality of such optical sensors are physically fixed, a trigonometric function is used to determine three directions (X / Y / R values) on the plane of the printer itself from the degree of movement detected by each optical sensor. Can be calculated.

As a result, since the movement distance for each sampling timing is known, the printer itself can recognize which position (X, Y coordinate position) is at the origin (0, 0) (= print start position). It becomes possible. The recognizable coordinates depend on the resolution of the sensor output value.
For one-way or two-way position sensing, values in a three-way position sensing process may be used.

  For example, in Patent Document 1, the position of the printer itself is detected by a relative position detection method using a plurality of navigation sensors (optical imaging sensors) in order to realize position control of a handy mobile printer that performs freehand scanning. The mechanism is disclosed.

However, in such a position detection method in the conventional handy mobile printer, when the printer is erroneously lifted from the paper surface in the Z direction, the relative position in the X and Y directions with respect to the origin (0, 0) is detected. It becomes impossible to lose sight of the actual position. Therefore, there were the following problems.
When the printer is lifted and returned to the paper surface, the position of the printer itself on the paper surface becomes unclear, and printing of the image being printed cannot be resumed, and the printing becomes useless.
Therefore, usability is poor because there is a restriction that printing will fail if the printer is moved away from the paper.

  The present invention has been made to solve the above-described problem. Even when the position of the handy mobile printer is lifted or tilted, if it reaches a certain height or tilt, printing can be continued as it is. The purpose is to enable normal printing to be completed.

  In order to achieve the above object, the present invention is a handy mobile printer that includes an ink jet head having nozzles and prints by ejecting ink from the nozzles according to image data while being scanned on a paper surface by a human hand. A coordinate detection sensor that detects a relative position on a plane along the plane of the paper, an acceleration sensor that detects at least an acceleration in a direction perpendicular to the plane, and a gyro sensor that detects an angular velocity of an inclination with respect to the plane. And position calculating means for calculating the position coordinates of the nozzle from position information detected by the coordinate detection sensor, and calculating a movement distance in a direction perpendicular to the plane from the acceleration information detected by the acceleration sensor. And an inclination angle with respect to the plane from the angular velocity information detected by the gyro sensor. A position coordinate correction that corrects the position coordinates of the nozzle calculated by the angle calculation means and the position calculation means by the movement distance calculated by the distance calculation means and the inclination angle calculated by the angle calculation means. And a head drive control means for controlling the inkjet head so that ink is ejected from the nozzle when the position coordinate of the nozzle corrected by the position coordinate correction means coincides with the image data. It is characterized by that.

  Even if the handy mobile printer according to the present invention is lifted or tilted, it can continue printing as long as it is up to a certain height or tilt, so that printing is not wasted and normal printing can be performed smoothly. Can be completed.

1 is a schematic bottom view showing a basic configuration of a first embodiment of a handy mobile printer according to the present invention. It is a block diagram which shows the structure of the control part which operates the handy mobile printer shown in FIG. Similarly, it is a flowchart showing the flow of the printing operation by the handy mobile printer, excluding the part relating to the calculation of the aerial position. It is a flowchart which shows the flow of the part which concerns on the aerial position calculation removed in FIG. FIG. 2 is a cross-sectional view in the X-axis direction when the inclination of the inkjet head shown in FIG. 1 is zero. FIG. 2 is a cross-sectional view in the X-axis direction when the inclination of the inkjet head shown in FIG. 1 is α. It is a typical bottom view which shows the basic composition of 2nd Embodiment of the handy mobile printer by this invention. It is a block diagram equivalent to FIG. 2 of 3rd Embodiment of the handy mobile printer by this invention. It is a block diagram equivalent to FIG. 2 of 4th Embodiment of the handy mobile printer by this invention. It is a block diagram equivalent to FIG. 2 of 5th Embodiment of the handy mobile printer by this invention. It is a block diagram equivalent to FIG. 2 of 6th Embodiment of the handy mobile printer by this invention. It is a typical bottom view which shows the basic composition of the conventional handy mobile printer. It is a typical bottom view which shows the example of an arrangement | sequence of the nozzle for ink discharge of the inkjet head in FIG. It is a block diagram which shows the structure of the control part which operates the handy mobile printer shown in FIG. It is a flowchart which similarly shows the flow of the printing operation by the handy mobile printer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Prior to that, a conventional handy mobile inkjet printer (hereinafter referred to as “handy mobile printer”) serving as the basis of the present invention will be described. This will be described with reference to FIGS.
FIG. 12 is a schematic bottom view showing a basic configuration of a conventional handy mobile printer.
The handy mobile printer 100 includes an inkjet head 2 that ejects ink on a bottom surface 1a that is a surface that comes into contact with a recording medium (generally paper), and a sensor for detecting a relative position on a plane along the paper surface. A plurality of coordinate detection sensors 3a and 3b. In this example, a pair of coordinate detection sensors 3a and 3b are arranged on both sides of the inkjet head 2 in the longitudinal direction on a center line that divides the width of the inkjet head 2 into two.

As shown in a schematic bottom view of FIG. 13, the inkjet head 2 has a plurality of rows of ink ejection nozzles 6 arranged on a rectangular bottom surface 2a along the width direction and the longitudinal direction.
The coordinate detection sensors 3a and 3b are optical sensors used in, for example, a pointing device, and a plurality of coordinate detection sensors 3a and 3b are arranged to detect the inclination of the inkjet head 2 on the plane.
In FIG. 12, the coordinate axes X and Y having the start position as the origin O (X: 0, Y: 0) are indicated by solid lines, and the coordinate axes X ′ and Y ′ after being rotated by the rotation angle θ are indicated by broken lines. ing.

  The rotation angle θ can be calculated using a trigonometric function from the “movement degrees (ΔX, ΔY)” output from the plurality of coordinate detection sensors 3a, 3b. Based on the information and the assembling distances a to d between the inkjet head 2 and the coordinate detection sensors 3a and 3b, the inkjet head 2 and each nozzle 6 thereof indicate where they are now with respect to the start position (the origin O). Recognize location information. This can be sequentially recognized at each sampling timing of the coordinate detection sensors 3a and 3b. The accuracy of the recognizable coordinates depends on the resolution of the output values of the coordinate detection sensors 3a and 3b.

FIG. 14 is a block diagram showing a configuration of a control unit for operating the handy mobile printer.
The control unit 110 mounted on the printed circuit board (PCB) includes a CPU 11, a host I / F 12, a RAM 13, a ROM 14, a head drive circuit 15, and a position calculation circuit 16. All of them are connected to the CPU 11 and the like via the system bus so as to exchange data and signals.
The CPU 11 manages various arithmetic processes and controls. The host I / F 12 is an input interface (IF) for control and images and operation commands between the personal computer or the smart device (abbreviated as “PC / suma device”) 8.

The RAM 13 is a working memory used when the CPU 11 executes calculations, image processing, and the like, and a random access memory that stores temporary data.
The ROM 14 is a read-only memory that stores fixed data such as firmware that is a program for controlling the hardware of the printer and drive waveform data of the inkjet head 2.

The head drive circuit 15 is a circuit that performs data processing for driving the inkjet head 2 and generates a drive waveform. The position calculation circuit 16 is a circuit for calculating the position information of the inkjet head 2 based on the information of the coordinate detection sensors 3a and 3b, and the CPU 11 may also serve as the position calculation circuit 16.
The handy mobile printer 100 also includes a print start button 7 that is a button that serves as a trigger for the user to determine the print start timing, and an LED 9 for displaying an operation state.

FIG. 15 is a flowchart showing a flow of printing operation by the handy mobile printer. “Print” in the description of this flowchart is the same as “print” or “image formation”.
When the handy mobile printer 100 is turned on, power is supplied to the control unit 110 shown in FIG. 14, and the CPU 11 executes the program stored in the ROM 14 to start the processing shown in FIG.
First, the CPU 11 performs initialization in step S1, and starts up each device such as the RAM 13.

When the user transmits image data (print data) to be printed from the PC / smart device 8 as the host device to the handy mobile printer 100, the image data is received in step S2. The image data is a print image starting from the origin.
In step S3, the CPU 11 adds additional information of coordinates to the received image data and stores it. This is because the coordinates of the image data are required when printing with freehand.

In order to notify the user of the timing at which the printer has received the image data and the image data has been coordinated, the CPU 11 causes the LED 9 on the printer to blink in step S4.
Accordingly, the user moves the handy mobile printer 100 to the start position of the area to be printed, matches the angles of the paper and the printer, and determines the initial position (U1). Then, the print start button 7 is pressed (U2).

On the other hand, the CPU 11 of the control unit 110 waits for the print start button 7 to be pressed in step S5, and starts the printing operation when the print start button 7 is pressed.
The CPU 11 acquires the initial position information at which the print start button 7 is pressed in step S 6, causes the position calculation circuit 16 to calculate the coordinates of each nozzle 6 using this as the origin, and stores it in the RAM 13. The coordinates of each nozzle 6 are determined by the assembly position of the inkjet head 2 with respect to the position of the coordinate detection sensors 3a and 3b, the position and interval of each nozzle 6 in the inkjet head 2, and the information is stored in the ROM 14 in advance. I can know. For example, the coordinates of the upper left nozzle 6 in the inkjet head 2 shown in FIG. 13 are (0, 0).

  When printing with freehand scanning, the printer does not know which direction to scan next. Therefore, since the next print data cannot be determined, the head drive circuit 15 needs to have print data in consideration of movement in any direction in advance. Therefore, the CPU 11 transfers image data around the print start position (printer periphery) from the RAM 13 to a memory (for example, SRAM) built in the head drive circuit 15 in the next step S7.

  The user can scan the printer in any direction on the plane freehand (U3). Therefore, when the printer is moved, the CPU 11 acquires the position information from the coordinate detection sensors 3a and 3b in step S8, calculates the coordinates of each nozzle using the position calculation circuit 16, and stores them in the RAM 13. Update location information. In step S9, it is determined whether the nozzle coordinates coincide with the image data. When the coordinates of the nozzles coincide with the image data, the CPU 11 causes the head drive circuit 15 to transfer the image data to the inkjet head 2 and ejects ink from the target nozzle 6 to perform printing in step S10.

Thereafter, the CPU 11 determines whether or not printing is finished in step S11. If the printing is not finished, the CPU 11 returns to step S8, acquires and updates the position information, and repeats the processing up to step S11 described above.
Since the coordinates of each nozzle are updated according to the sampling period of the coordinate detection sensors 3a and 3b, the determination whether to print or not depends on this sampling period.
This location information update may be performed by a hardware circuit (for example, ASIC or FPGA) instead of the CPU 11.
When the printing is completed, the process of the CPU 11 proceeds from step S11 to step S12, for example, turns on the LED 9, notifies the user to that effect, and ends the printing operation.

However, in such a conventional handy mobile printer, when the printer is lifted, the coordinates of each nozzle of the inkjet head are lost, and printing cannot be resumed. Even if printing is resumed, the position information will be different from the actual position, so the images will overlap or blank, resulting in an abnormal image, so it will be necessary to reprint on another sheet of paper As a result, the paper is wasted.
Therefore, there is a restriction that if the printer is lifted even a little, printing fails, and there is a problem that usability to the user is poor.

The present invention has been made in order to solve such problems in the handy mobile printer, and has the following features.
In short, by providing the handy mobile printer with an acceleration sensor and a gyro sensor, the position of the printer itself is not lost even during unexpected scanning (lifting scanning), and nozzle coordinate information corresponding to the height and inclination is sequentially calculated. Thereby, since the coordinate comparison between the print image and the nozzle coordinates can be performed, normal printing can be continued and resumed, and normal printing can be completed.

The handy mobile printer that is the object of the present invention is a small-sized inkjet printer that does not have a paper feed mechanism and can be printed while being scanned by a human hand.
The “printer” is also referred to as “printing apparatus”, “printing apparatus”, “recording apparatus”, “image forming apparatus”, and the like, and includes any of them.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
[First Embodiment]
FIG. 1 is a schematic bottom view showing a basic configuration of a first embodiment of a handy mobile printer according to the present invention. In FIG. 1, the same parts as those in FIG. 12 are denoted by the same reference numerals, and description thereof is omitted.
The handy mobile printer 1 according to the first embodiment shown in FIG. 1 includes, in addition to the configuration of the conventional handy mobile printer 100 shown in FIG. An acceleration sensor 4 and a gyro sensor 5 are provided.

The acceleration sensor 4 is a well-known sensor that detects acceleration, which is a time derivative of speed, and can measure the value of acceleration acting on an object. There are 1 to 3 axes, and in this embodiment, 3 axes are assumed. However, any acceleration sensor that can detect acceleration in a direction perpendicular to a plane at least along the paper surface may be used.
The gyro sensor 5 is also a well-known sensor, and is a sensor that detects an angular velocity, and can detect the angle of an object by one-time integration calculation processing. There are 1 to 3 axes, and in this embodiment, 3 axes are assumed. However, when the main scanning direction that is the width direction of the inkjet head 2 in the plane along the paper surface is X, the sub-scanning direction that is the longitudinal direction is Y, and the height direction perpendicular to the plane is Z, the XZ direction It is desirable to be able to detect the inclination in the YZ direction.

When the user lifts the handy mobile printer 1, the detection resolution of the coordinate detection sensors 3a and 3b is significantly reduced, and the detected coordinate information is greatly different from the actual information.
At this time, the moving distance in the height direction perpendicular to the plane can be calculated from the acceleration information of the acceleration sensor 4 by the double integration calculation process. Therefore, the lifted acceleration can be detected and the distance of the height change can be calculated. Further, since it is impossible to lift only in the vertical direction from the paper surface, the distances in the X and Y directions are calculated in the same manner.
Since the coordinate information can be corrected by the distance information, the handy mobile printer 1 can continue printing without losing sight of the position information.

Generally, when calculating the distance from the acceleration, since the integration calculation process is performed twice, the accuracy of the distance is inferior to that of the coordinate detection sensor.
However, the detection accuracy of the coordinate detection sensors 3a and 3b is more than 10 times the general print resolution (600 dpi or 1200 dpi), and the distance accuracy after the calculation processing from the acceleration is also equal to the print resolution. There is something to have.
Finally, if an accuracy equivalent to the print resolution can be calculated, position correction that does not affect the image is established.

Furthermore, from the angular velocity information of the gyro sensor 5, the angle of the handy mobile printer 1 (inclination with respect to a direction parallel to the paper surface in the air) can be calculated by integration calculation processing.
Therefore, the inclinations of the three axes (X, Y, Z) of the handy mobile printer 1 in the air can be measured and calculated. By grasping the inclination information in the air from this angle information, the position information of each nozzle 6 shown in FIG. 13 can be calculated.

In general, when calculating the distance from the angular velocity, an integration calculation process is performed, so that the accuracy of the angle is inferior to that of the coordinate detection sensor.
However, the detection accuracy of the coordinate detection sensor is more than 10 times the general print resolution (600 dpi or 1200 dpi), and the angle accuracy after the calculation processing from the angular velocity has the same accuracy as the print resolution.
Finally, if an accuracy equivalent to the print resolution can be calculated, position correction that does not affect the image is established.

FIG. 2 is a block diagram showing a configuration of a control unit for operating the handy mobile printer, and portions corresponding to those in FIG. 14 are denoted by the same reference numerals. However, the function of the CPU 11 and the program stored in the ROM 14 are different from those of the CPU 11 and the ROM 14 in FIG.
The handy mobile printer 1 of this embodiment has the same configuration as the conventional one described with reference to FIG. 14, and the above-described acceleration sensor 4, gyro sensor 5, and control unit 10 in order to detect the printer's airborne state. Is provided with an aerial position calculation circuit 17.
The aerial position calculation circuit 17 is also connected to the CPU 11 and the like via the system bus so as to exchange data and signals.

  The aerial position calculation circuit 17 calculates the aerial position with respect to the paper surface of the handy mobile printer 1 from the acceleration information from the acceleration sensor 4 and the angular velocity information from the gyro sensor 5. The aerial position calculation circuit 17 is assumed to be an ASIC or FPGA. However, if the CPU 11 can perform sufficiently high-speed processing for print scanning, it can be replaced with the function of the CPU 11. In FIG. 2, an independent aerial position calculation circuit 17 is shown.

In the control unit 10 of the first embodiment, the CPU 11 and the position calculation circuit 16 correspond to position calculation means for calculating the position coordinates of the nozzles of the inkjet head 2 from the position information detected by the coordinate detection sensors 3a and 3b. .
Further, the CPU 11 and the aerial position calculation circuit 17 are detected by the gyro sensor 5 and the distance calculation means for calculating the movement distance in the direction perpendicular to the plane along the paper surface from the acceleration information detected by the acceleration sensor 4. This corresponds to angle calculation means for calculating an inclination angle with respect to the plane from the angular velocity information.

Further, the position coordinate correcting unit corrects the position coordinates of the nozzle calculated by the position calculating unit by the CPU 11 and the RAM 13 based on the movement distance calculated by the distance calculating unit and the inclination angle calculated by the angle calculating unit. Perform functions.
Then, when the position coordinates of the nozzles corrected by the position coordinate correction means coincide with the image data by the CPU 11 and the head drive circuit 15, head drive control for controlling the inkjet head 2 so that ink is ejected from the target nozzles. Fulfills the function of the means.

  FIG. 3 is a flowchart showing the flow of the printing operation by the handy mobile printer 1 of the first embodiment, excluding the part relating to the calculation of the aerial position. FIG. 4 is a flowchart of the part relating to the calculation of the aerial position. FIGS. 3 and 4 are flowcharts showing a series of printing operations, in which the flow lines of the same terminal symbols are connected.

3 are executed by the CPU 11 and the like of the control unit 110 shown in FIG. 14 of the conventional handy mobile printer. To S12. Therefore, description of the processing of each step is omitted. Each operation of steps U1 to U3 performed by the user is the same as that in FIG.
However, in step S104, the LED 9 blinks to indicate completion of preparation for printing start, and in step S112, the LED 9 is lit to notify the user of printing completion. However, instead of the LED 9, a speaker or buzzer is provided, and the voice or buzzer sound May be notified.

  The coordinate detection sensors 3a and 3b, the acceleration sensor 4, and the gyro sensor 5 mounted on the handy mobile printer 1 always detect position information, acceleration information, and angular velocity information at regular time intervals. Therefore, after the CPU 11 of the control unit 10 transfers the image data around the printer to the head drive circuit 15 in step S107, the position information is acquired from the coordinate detection sensors 3a and 3b in step S108, and the coordinates of each nozzle are calculated. The position information stored in the RAM 13 is updated.

At the same time, the aerial position calculation circuit 17 acquires and updates angular velocity information from the gyro sensor 5 in step S120 of FIG. 4, and acquires and updates acceleration information from the acceleration sensor 4 in step S121. The update is performed by rewriting the angular velocity information and the acceleration information stored in the RAM 13, respectively.
In step S122, the aerial position calculation circuit 17 integrates the updated angular velocity information and calculates angle information of the inclination with respect to a plane parallel to the paper surface in the air. In step S123, the updated acceleration information is integrated to calculate distance (height) information from the paper surface.

  In step S124, it is determined whether or not acceleration is generated in the Z-axis (height) direction. As a result, if no acceleration is generated, the process proceeds to step S109 in FIG. 3. If the coordinates of the nozzle match the image data, printing is performed in step S110. Return to S120 and S121.

If it is determined in step S124 in FIG. 4 that acceleration has occurred, it indicates that the printer is floating above the paper. Therefore, the CPU 11 determines whether or not the height or inclination is equal to or less than the threshold set in step S125 based on the information calculated by the aerial position calculation circuit 17 in steps S122 and S123.
Here, the threshold value is a threshold value for determining whether or not the ink droplets ejected from the nozzle 6 can land on the paper surface with accuracy within specifications, and in short, is a threshold value for determining whether printing can be performed normally.

Here, the threshold value will be described.
5 is a cross-sectional view in the X-axis direction when the inclination of the inkjet head 2 shown in FIG. 1 is zero, and FIG. 6 is a cross-sectional view in the X-axis direction when the inclination is also α.
For example, when the handy mobile printer 1 is parallel to the paper surface P as shown in FIG. 5, the interval between the nozzles 6 of the inkjet head 2 is indicated by N, the height is indicated by H, and the head width is indicated by X.

When the printer is actually tilted in the air, the height varies depending on each nozzle position, as shown in FIG. However, if the distance that the center of the X-axis direction (main scanning direction) of the inkjet head 2 is lifted is Z, and the inclination angle in the X-axis direction is α, the maximum rising distance, the minimum rising distance, and the nozzle interval are Can be calculated.
Maximum ascent distance = Z + (X / 2) sinα
Minimum ascent distance = Z- (X / 2) sinα
Nozzle spacing = Ncosα

When the inkjet head 2 is tilted in the Y axis direction (sub-scanning direction), which is the length direction, the maximum lift distance and the minimum lift distance are Z and the tilt angle in the Y axis direction is β. And the nozzle interval can be calculated by the following equation.
Maximum ascent distance = Z + (Y / 2) sinβ
Minimum ascent distance = Z- (Y / 2) sinβ
Nozzle spacing = Ncosβ

Assuming that the ink droplets from the nozzle 6 can be ejected perpendicularly to the paper surface P, the coordinates replaced on the plane of each nozzle 6 can be calculated from the above-mentioned information. Can be calculated.
If neither the height (distance) nor the inclination (angle) is less than or equal to the threshold, that is, if either exceeds the threshold, the print image quality is adversely affected, and printing is stopped in step S130 in FIG. Inclination stops printing when either the XZ direction inclination or the YZ direction inclination exceeds a threshold value.

This corresponds to a function of means for stopping printing when at least one of the movement distance calculated by the distance calculation means and the inclination angle calculated by the angle calculation means exceeds a set threshold value. Note that the threshold set for the tilt angle may be changed according to the printing resolution. In this case, the threshold is lowered when the printing resolution is high than when the printing resolution is low.
If both the height and the inclination are less than or equal to the threshold value, the aerial position calculation circuit 17 coordinates angle information in step S126 and coordinates distance information in step S127 in order to continue printing. At this time, the coordinates are converted into coordinates of the output resolution of the coordinate detection sensors 3a and 3b.

Then, the CPU 11 obtains the coordinate position of each nozzle 6 calculated in steps S126 and S127 as the correction position information, and obtains it in step S128 in FIG. 3, and obtains it from the coordinate detection sensors 3a and 3b in step S108 and stores it in the RAM 13. Update the stored position coordinates.
In short, when the handy mobile printer 1 is lifted, a process for performing correction based on position information in the air is realized. This process corresponds to the function of the position coordinate correction means.
Subsequent steps S109 to S112 are the same as steps S9 to S12 described with reference to FIG. The head drive that controls the inkjet head 2 so that ink is ejected from the target nozzle when the determination in step S109 and the printing process in step S110 match the position data of the nozzle corrected by the position coordinate correction means with the image data. This corresponds to the function of the control means.

With the above control process, even when the handy mobile printer 1 is lifted, the coordinate information of each nozzle 6 can be corrected based on the acceleration information and the angular velocity information, and the ink ejection timing can be determined based on the corrected information. Can be adjusted. Accordingly, the handy mobile printer 1 can continue printing without losing sight of the position information.
For this reason, if the handy mobile printer 1 of this embodiment is used, printing can be continued as it is even if the handy mobile printer 1 is lifted to some extent from the paper surface, and printing is not wasted. And normal printing can be completed smoothly, and usability is improved.
Note that the scanning speed on the plane of the handy mobile printer 1 is detected. If the scanning speed is too high and printing cannot be continued normally, printing is stopped and the scanning speed is below a predetermined value that allows normal printing. Then, after correcting the position from the acceleration information, printing may be resumed.

[Second Embodiment]
Next, a second embodiment of the handy mobile printer according to the present invention will be described with reference to FIG. FIG. 7 is a schematic bottom view showing the basic configuration of the handy mobile printer 1 ′. The same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.
The handy mobile printer 1 ′ of the second embodiment is different from the handy mobile printer 1 of the first embodiment only in that a plurality of acceleration sensors and gyro sensors are provided at intervals.

That is, on the bottom surface 1a of the handy mobile printer 1 ', a pair of acceleration sensors 4a and 4b are installed at one diagonal position, and a pair of gyro sensors 5a and 5b are installed at a distance from each other at an interval. doing.
As described above, when the acceleration sensor and the gyro sensor are respectively installed at the diagonal positions of the bottom surface 1a of the handy mobile printer 1 ', it is possible to detect the tilt that is difficult to detect with one configuration with higher accuracy.
For example, when rotating around a line connecting the acceleration sensor 4a and the gyro sensor 5a, the acceleration sensor 4a and the gyro sensor 5a on the line can detect only a minute change. However, the acceleration and the angular velocity that can be detected by the other acceleration sensor 4b and gyro sensor 5b can detect a large change, although it depends on the size of the handy mobile printer 1 '.

For this reason, even when the correction position information is actually calculated, the actual operation can be accurately followed.
Therefore, according to the second embodiment, the accuracy of the position correction information when the printer is lifted can be improved.
Although the configuration of the control unit in the second embodiment is not shown, the configuration is similar to that of the control unit 10 in the first embodiment shown in FIG. 2, and the aerial position calculation circuit 17 includes a plurality of acceleration sensors 4a, The detection signals of 4b and the plurality of gyro sensors 5a and 5b are input.

[Third Embodiment]
Next, a third embodiment of the handy mobile printer according to the present invention will be described with reference to FIG. FIG. 8 is a block diagram corresponding to FIG. 2 of the handy mobile printer 1A. The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted. However, the function of the CPU 11 in the control unit 10A and the program stored in the ROM 14 are slightly different from those of the CPU 11 and the ROM 14 of the control unit 10 in FIG.
Although the schematic bottom views of the handy mobile printers of the following third to sixth embodiments are omitted, the handy mobile printers of the third, fourth, and sixth embodiments are shown in FIG. It is the same as the schematic bottom view of the first embodiment. The handy mobile printer of the fifth embodiment is provided with one coordinate detection sensor 3 instead of the pair of coordinate detection sensors 3a and 3b in the schematic bottom view of the first embodiment shown in FIG. Yes.

In the first embodiment, the coordinate position of each nozzle 6 of the inkjet head 2 is calculated only by the position detection information of the plurality of coordinate detection sensors 3a and 3b on the plane. On the other hand, in the third embodiment, the coordinate information of the nozzle 6 is calculated using (accumulating) acceleration information from the acceleration sensor 4.
Therefore, the handy mobile printer 1A of the third embodiment is configured to input the detection signal of the acceleration sensor 4 to the CPU 11 together with the aerial position calculation circuit 17 of the control unit 10A.

  In the position detection information by the coordinate detection sensors 3a and 3b, a slight detection shift occurs according to the speed. When operating at a speed within the specification range of the coordinate detection sensors 3a and 3b, there is a slight deviation, but errors are accumulated. Therefore, it is desirable to make errors as small as possible for printing by a printer.

Since the speed can be detected by integrating the acceleration detected by the acceleration sensor 4, the CPU 11 can correct the coordinate information detected by the coordinate detection sensors 3a and 3b according to the detected speed. Thus, the position calculation circuit 16 can accurately calculate the coordinate position of each nozzle 6 of the inkjet head 2.
Therefore, according to the third embodiment, it is possible to further improve the position detection accuracy on the plane, and it is possible to realize high resolution of the printed image.

[Fourth Embodiment]
Next, a fourth embodiment of the handy mobile printer according to the present invention will be described with reference to FIG. FIG. 9 is a block diagram corresponding to FIG. 2 of the handy mobile printer 1B. The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted. However, the function of the CPU 11 in the control unit 10B and the program stored in the ROM 14 are slightly different from those of the CPU 11 and the ROM 14 in the control unit 10 in FIG.
In the first embodiment, the coordinate position of each nozzle 6 of the inkjet head 2 is calculated only by the position detection information of the plurality of coordinate detection sensors 3a and 3b on the plane. On the other hand, in the fourth embodiment, the coordinate position of the nozzle 6 is calculated using (adding) the angular velocity information from the gyro sensor 5.

Therefore, the handy mobile printer 1B of the fourth embodiment is configured to input the detection signal of the gyro sensor 5 to the CPU 11 together with the aerial position calculation circuit 17 of the control unit 10B.
The position detection information by the coordinate detection sensors 3a and 3b is slightly misaligned according to the rotation speed. When operating at a rotational speed within the specification range of the coordinate detection sensors 3a and 3b, there is a slight deviation, but errors are accumulated. Therefore, it is desirable to make the errors as small as possible for printing by a printer.

Since the gyro sensor 5 can detect the angular velocity (rotational speed), the CPU 11 can correct the coordinate information detected by the coordinate detection sensors 3a and 3b according to the detected angular velocity. Thus, the position calculation circuit 16 can accurately calculate the coordinate position of each nozzle 6 of the inkjet head 2.
Therefore, according to the fourth embodiment, it is possible to further improve the position detection accuracy on the plane, and it is possible to realize a higher resolution of the printed image.

[Fifth Embodiment]
Next, a fifth embodiment of the handy mobile printer according to the present invention will be described with reference to FIG. FIG. 10 is a block diagram corresponding to FIG. 2 of the handy mobile printer 1C. The same parts as those in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted.
The control unit 20 of the handy mobile printer 1C of the fifth embodiment replaces the CPU 11 and the aerial position calculation circuit 17 of the control unit 10 shown in FIG. 2 in the first embodiment with a position calculation circuit 16 and a head drive. A SoC FPGA 18 incorporating the circuit 15 is mounted.
The SoC FPGA 18 can exchange data and signals with the host I / F 12, the RAM 13, and the ROM 14 via the system bus.
In addition, the handy mobile printer 1C only needs to provide one coordinate detection sensor 3 instead of providing a plurality of coordinate detection sensors 3a and 3b to detect coordinate information.

As the coordinate detection sensor 3, for example, a high-resolution CMOS sensor is used. As a method for detecting the degree of movement, the degree of movement is not calculated by calculating the degree of movement of the image of interest but by performing image pattern matching. It is possible to calculate up to the rotation direction.
“SoC” of the SoC FPGA 18 is an abbreviation of System On a Chip, and is a system incorporated in one chip. “FPGA” is an abbreviation for Field Programmable Gate Array, which means a gate array that can be programmed in the field.

  The FPGA includes a logic cell, a multiplier, a RAM, and the like, which are materials constituting the circuit, and a dedicated circuit is created by combining them, and the dedicated circuits are connected and operated in the order of processing. Instead of operating in sequence according to a program as in the case of a CPU, when a signal is received, it operates immediately by hardware processing, and parallel processing of a plurality of functions is also possible.

The SoC FPGA 18 has all the functions of the CPU 11, the head drive circuit 15, the position calculation circuit 16, and the aerial position calculation circuit 17 in the control unit 10 of the first embodiment. That is, the above-described position calculation means, distance calculation means, angle calculation means, position coordinate correction means, and head drive control means are integrated into one module.
Therefore, the handy mobile printer 1C according to the fifth embodiment uses one coordinate detection sensor 3 and uses the SoC FPGA 18, which is a one-chip programmable gate array, for the control unit 20. Realize high speed (high productivity).

[Sixth Embodiment]
Next, a sixth embodiment of the handy mobile printer according to the present invention will be described with reference to FIG. FIG. 11 is a block diagram corresponding to FIG. 2 of the handy mobile printer 1D. The same parts as those in FIG.
In the handy mobile printer 1D of the sixth embodiment, the control unit 10 shown in FIG. 2 in the first embodiment is changed to a control unit 30. The control unit 30 has only the sensor abnormality detection circuit 19 added to the same configuration as the control unit 10. The sensor abnormality detection circuit 19 is also connected to the CPU 11 and the like via the system bus so as to exchange data and signals.

The sensor abnormality detection circuit 19 inputs all the detection signals of the plurality of coordinate detection sensors 3a and 3b, the acceleration sensor 4, and the gyro sensor 5, and if any of them is abnormal, detects the sensor abnormality, This is sensor abnormality detection means for informing the CPU 11.
For example, when the user moves the handy mobile printer 1D freehand, the information of the coordinate detection sensor 3a or 3b is not updated, and the distance and angle information by the detection signals of the acceleration sensor 4 and the gyro sensor 5 are updated. To do.
In this case, it is determined that the coordinate detection sensor 3a or 3b that is not updated has failed. Alternatively, when the information of the coordinate detection sensors 3a and 3b and the gyro sensor 5 is updated and the information of the acceleration sensor 4 is not updated, it is determined that the acceleration sensor 4 has failed.

  That is, the sensor abnormality detection circuit 19 determines which sensor has not been updated based on the input information from each sensor. When any of the coordinate detection sensors 3a, 3b, the acceleration sensor 4, and the gyro sensor 5 fails and a sensor abnormality is detected, the CPU 11 turns on or blinks the LED corresponding to the failed sensor. Inform the user of sensor abnormality. Instead of the LED, a speaker, a buzzer, or the like may be operated to notify the user of the sensor abnormality by voice or buzzer sound.

When the sensor abnormality detection circuit 19 detects a sensor abnormality in the middle of printing, if the information that cannot be updated due to a failure is information that can be supplemented with information from another sensor, the function is replaced by that sensor and printing is continued. .
By doing so, it is possible to reduce the time during which the user cannot use the printer (downtime) even if a part of the sensor breaks down.

For example, even if one of the coordinate detection sensors 3a and 3b fails, low-resolution printing can be continued using information obtained from the acceleration sensor 4 and the gyro sensor 5.
Therefore, when any abnormality of the coordinate detection sensors 3a and 3b is detected by the sensor abnormality detection circuit 19 during printing, printing is continued at a low resolution as it is, or printing is stopped once and a new low-resolution image is detected. The user may be allowed to select whether to start printing.

[Program Embodiment]
The embodiment of the program according to the present invention is a program for causing a computer corresponding to the control unit 10 that controls the handy mobile printer 1 of the first embodiment shown in FIG. 2, for example, to function as the following means.
As shown in FIGS. 1 and 13, the handy mobile printer 1 includes an inkjet head 2 having a nozzle 6 and coordinate detection sensors 3 a and 3 b that detect a relative position on a plane along a paper surface. Yes. Furthermore, an acceleration sensor 4 that detects acceleration in a direction perpendicular to at least the plane and a gyro sensor 5 that detects an angular velocity of inclination with respect to the plane are provided. Then, printing is performed by ejecting ink from the nozzle 6 according to the image data while scanning the paper surface by a human hand.

The program causes the computer to function at least the following means.
Position calculation means for calculating the position coordinates of the nozzle 6 from position information detected by the coordinate detection sensors 3a and 3b;
A distance calculating means for calculating a moving distance in a direction perpendicular to the plane from acceleration information detected by the acceleration sensor 4;
An angle calculating means for calculating an inclination angle with respect to the plane from the angular velocity information detected by the gyro sensor 5;

A position coordinate correction unit that corrects the position coordinates of the nozzle 6 calculated by the position calculation unit based on the movement distance calculated by the distance calculation unit and the inclination angle calculated by the angle calculation unit;
A head drive control means for controlling the ink jet head 2 so that ink is ejected from the nozzle 6 when the position coordinates of the nozzle 6 corrected by the position coordinate correction means coincide with the image data;

Furthermore, it is also possible to provide a program for causing a computer corresponding to each control unit that controls each handy mobile printer of each of the other embodiments described above to function as each unit necessary for the control unit.
The computer that controls the handy mobile printer is, for example, a microcomputer that includes the CPU 11, the RAM 13, the ROM 14, and the like of the control unit 10 shown in FIG.

  The program may be stored in the ROM 14 constituting the control unit 10 of the handy mobile printer from the beginning, or may be provided by being recorded on a CD-ROM, a floppy disk or other computer-readable recording medium. . Alternatively, the program can be provided so that it can be downloaded to the memory of the handy mobile printer via a network such as the Internet.

As mentioned above, although each embodiment of this invention has been described, the specific configuration of each part of the embodiment, the content of processing, and the like are not limited to those described therein.
Moreover, this invention is not limited to each embodiment mentioned above, It cannot be overemphasized that it is not limited at all except having the technical feature described in each claim of a claim.
Furthermore, the configuration examples, operation examples, modification examples, and the like of each embodiment described above may be changed or added as appropriate, or a part thereof may be deleted, and may be implemented in any combination as long as they do not contradict each other. Of course.

1, 1 ', 1A-1D, 100: Handy mobile printer (handy mobile inkjet printer) 2: Inkjet head
3, 3a, 3b: Coordinate detection sensor 4, 4a, 4b: Acceleration sensor
5, 5a, 5b: Gyro sensor 6: Nozzle 7: Print start button
8: Personal computer or smart device (PC / Smadeva)
9: LED 10, 10A, 10B, 20, 30, 110: Control unit 11: CPU
12: Host I / F 13: RAM 14: ROM 15: Head drive circuit
16: Position calculation circuit 17: Aerial position calculation circuit 18: SoC FPGA
19: Sensor abnormality detection circuit

Special table 2010-520087 publication 10

Claims (12)

A handy mobile printer that includes an inkjet head having nozzles and that prints by ejecting ink from the nozzles according to image data while being scanned on a paper surface by a human hand,
A coordinate detection sensor for detecting a relative position on a plane along the paper surface;
An acceleration sensor that detects acceleration in a direction perpendicular to at least the plane;
A gyro sensor for detecting an angular velocity of inclination with respect to the plane;
Position calculating means for calculating position coordinates of the nozzle from position information detected by the coordinate detection sensor;
Distance calculating means for calculating a moving distance in a direction perpendicular to the plane from acceleration information detected by the acceleration sensor;
Angle calculating means for calculating an inclination angle with respect to the plane from angular velocity information detected by the gyro sensor;
Position coordinate correction means for correcting the position coordinates of the nozzle calculated by the position calculation means by the movement distance calculated by the distance calculation means and the inclination angle calculated by the angle calculation means;
Head drive control means for controlling the inkjet head so that ink is ejected from the nozzles when the position coordinates of the nozzles corrected by the position coordinate correction means match the image data;
Handy mobile printer characterized by providing The handy mobile printer according to claim 1,
A handy mobile printer comprising: means for stopping printing when at least one of a moving distance calculated by the distance calculating means and an inclination angle calculated by the angle calculating means exceeds a set threshold value .   The handy mobile printer according to claim 2, wherein a threshold value set for the tilt angle is changed according to a printing resolution.   The handy mobile printer according to any one of claims 1 to 3, wherein a plurality of the acceleration sensors are installed at intervals.   The handy mobile printer according to any one of claims 1 to 4, wherein a plurality of the gyro sensors are installed at intervals.   The handy mobile printer according to any one of claims 1 to 5, wherein the position calculation unit calculates position coordinates of the nozzles using acceleration information detected by the acceleration sensor.   6. The handy mobile printer according to claim 1, wherein the position calculating unit calculates the position coordinates of the nozzles using angular velocity information detected by the gyro sensor. 7.   8. The position calculation unit, the distance calculation unit, the angle calculation unit, the position coordinate correction unit, and the head drive control unit are integrated into one module. The handy mobile printer described in the section. In the handy mobile printer according to any one of claims 1 to 8,
A handy mobile printer, comprising: a sensor abnormality detection unit that detects a sensor abnormality when any of the coordinate detection sensor, the acceleration sensor, and the gyro sensor fails. The handy mobile printer according to claim 9, wherein
A handy mobile printer, comprising: a notification means for notifying the sensor abnormality when the sensor abnormality detection means detects the sensor abnormality. The handy mobile printer according to claim 9 or 10,
Handy provided with means for continuing printing when the sensor abnormality detecting means detects abnormality of the sensor during printing and information that cannot be updated can be compensated by information from other sensors. Mobile printer. An inkjet head having a nozzle; a coordinate detection sensor that detects a relative position on a plane along the plane of the paper; an acceleration sensor that detects acceleration in a direction at least perpendicular to the plane; and an angular velocity of inclination with respect to the plane A computer that controls a handy mobile printer that prints by ejecting ink from the nozzles according to image data while being scanned on a paper surface by a human hand,
Position calculating means for calculating position coordinates of the nozzle from position information detected by the coordinate detection sensor;
Distance calculating means for calculating a moving distance in a direction perpendicular to the plane from acceleration information detected by the acceleration sensor;
Angle calculating means for calculating an inclination angle with respect to the plane from angular velocity information detected by the gyro sensor;
Position coordinate correction means for correcting the position coordinates of the nozzle calculated by the position calculation means by the movement distance calculated by the distance calculation means and the inclination angle calculated by the angle calculation means;
A program for functioning as a head drive control unit for controlling the inkjet head so that ink is ejected from the nozzle when the position coordinate of the nozzle corrected by the position coordinate correction unit coincides with the image data.

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