JPH0555309B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a printing device, and particularly to a printing device equipped with a printing head moving mechanism suitable for printing on large size paper.

[Technical background of the invention]

FIG. 1 is a perspective view showing an example of a printer mechanism portion of a conventional printing device. Print head 1
is arranged close to the platen 3 through which the paper 2 is fed. The print head 1 is movably supported by a guide bar 4 disposed parallel to the platen 3, and is fixed to a head belt 5. This head belt 5 is stretched parallel to the guide bar 4 and is driven by a head motor 6. A bracket cable 8 from a control printed circuit board 7 is connected to the print head 1, and current is supplied to the print head 1 through the cable 8. One end of the platen 3 is connected to a driving step motor 10 via a gear 9.

In the conventional printing device (serial printer for dot character printing) as described above, print data containing a mixture of print character codes, control codes such as CR (carriage return) and LF (line feed) is sent from a host device (not shown). It's coming. The control circuit in the printing device selects CR, CR, etc. from the received print data.
A control code such as CF is detected, the print head 1 is moved along the guide bar 4 by the head motor 6 for carriage return, and the platen 3 is rotated by the step motor 10 to line feed the paper 2 to print the next print. Printing of the print data was started from the next line.

[Problems with background technology]

In the conventional printing device as described above, when it is desired to print on paper with a large paper width, the longitudinal dimension W of the printer mechanism section is increased, and each part such as the platen 3, guide bar 4, head belt 5, etc. is lengthened, and the head motor is 6 and step motor 10
capacity must be increased. Therefore, as the cost of parts increases, the device becomes larger and consumes more power, requiring an expensive power source.
It had the disadvantage of being extremely uneconomical.

Therefore, in order to eliminate the above-mentioned drawbacks, a printing device as shown below has been proposed. That is, this device has a printing section that incorporates a print head, a speed detector that detects the moving speed of the print head, and a control circuit that controls the print drive pulse width and the drive timing of the print head. When a person holds the printing unit and scans the paper, the control circuit changes the drive timing of the print head according to the speed of the print head relative to the paper, and prints based on the print data sent from the host device. It is printed.

With such an apparatus, it is possible to print on a large size paper simply by increasing the scanning distance of the printing section, and the drawbacks of the previous example can be overcome. However, with this method, even if the control circuit built into the printing unit detects a CR or LF code and stops printing that line, a person must move the printing unit by holding it, so the next line cannot be printed. When starting printing, it is unclear at what timing printing can be performed. For example, even if you start printing the next line 3 seconds after the previous line finishes printing, the print position of the next line is not fixed because the person moves the print unit, and the print position of each line shifts. There were flaws. Moreover, the fact that the printer is ready to start printing the next line after 3 seconds has elapsed means that in any case, it is necessary to wait 3 seconds before starting printing, resulting in a time loss.

[Purpose of the invention]

In view of the above-mentioned drawbacks, an object of the present invention is to be able to print on large size paper at a low cost without increasing the size of parts and devices, and to
An object of the present invention is to provide a printing device capable of printing each line at a predetermined position.

[Summary of the invention]

The printing device of the present invention includes a print head, a speed detector that detects the moving speed of the print head, and a control circuit that takes in the speed of the print head and controls the print drive pulse width and the drive timing of the print head. When the printing section is manually scanned over the paper, the control circuit controls the printing head (printing section).
Controls printing on the paper according to print data sent from a host device while changing the print head drive timing in accordance with the speed of the print head, and also controls carriage return and line feed from the print data. When a code is detected, printing of the corresponding line is stopped even if the printing section is moving, and
Furthermore, the speed detector recognizes the line feed of the printing part because the speed of the printing part once becomes zero and then starts moving again, and when the speed of the printing part reaches a predetermined value, the next line starts moving. It is characterized by controlling the start of printing.

[Embodiments of the invention]

An embodiment of the printing device of the present invention will be described below with reference to the drawings. FIG. 2 is an overview diagram showing an embodiment of a printing section realizing the printing device of the present invention. The printing section 20 has a shape that is easy for a person to hold, and a printing head (not shown) is disposed on a base 21 at the bottom of the printing section 20. A cable 22 for transmitting print data is connected to the upper part of the printing section 20, and a connector 23 for connecting to a host device (not shown) is provided at the end of the cable 22. Further, together with this cable 22, a power line 25 of an AC adapter 24 that converts AC 100V into DC power is connected to the printing unit 20, and DC power is supplied through the power line.

FIG. 3 is a diagram showing the bottom of the printing section 20 shown in FIG. 2, in which a printing head heat generating section 26 and a detection roller 27 forming a speed detector for detecting the moving speed of the printing head are mounted on the base 21 at the bottom. is installed. Note that the detection roller 27 rotates while contacting the paper when moving the printing unit 20. FIG. 4 is a diagram showing the contents of the printing unit 20 of FIG. 2 with the housing cover removed. The part 28 on the back side of the bottom base 21 is the print head heating part 2.
The pattern led from 6 is a part that is led to the opposite side through a through hole, and this part 28 is electrically connected to the IC 30 through a flat cable 29. A signal line 31 constituting the cable 22 shown in FIG. 2 is connected to this IC 30 via a connector 32. In addition, IC30
The connector 32 is fixed on an IC mounting base 33, and a control circuit is formed inside the IC 30. Good conductors 34 are bonded to the side surface of the detection roller 27 in radial and arc shapes. Two brushes are disposed such that a brush 35A is in contact with the arcuate portion of the good conductor 34, and a brush 35B is in contact with the radial portion. The ends of these brushes 35A, 35B are electrically connected to the IC 30 by lead wires. Detection roller 2
When the brush 7 rotates, the brushes 35A and 35B are repeatedly short-circuited and opened, and the resulting electric signal is transmitted to the IC 30.

FIG. 5 is a configuration diagram showing an example of a control circuit within the IC 30 of FIG. 4. Microcomputer 3
6 drives an interface section 37 for transmitting and receiving data with a host device (not shown), a speed detection control circuit 38 connected to brushes 35A and 35B in FIG. 3, and a print head heat generating section 26. A printhead control driver 39 is connected. Such a control circuit is supplied with power from the AC adapter 24, and the microcomputer 36 takes in the speed change data of the printing unit 20 from the speed detection control circuit 38 and outputs it to the print head control driver 39.
Control is performed to drive the printing unit 20 at a timing corresponding to the speed of the printing unit 20. Note that the detection roller 27, brushes 35A, 35B, and speed detection control circuit 38 constitute a speed detector.

Next, the operation of this embodiment will be explained. Now, as shown in FIG. 6, a case will be described in which printing is performed on paper 40 by manually moving the printing unit 20 from left to right. The ruler 41 is provided to move the printing section 20 linearly. At this time, the detection roller 27 rotates as shown in FIGS. 3 and 4, and the brush 35
The brushes 35A and 35B are repeatedly opened and shorted across the radial portion of the brush 4. These brushes 35A, 35
When B is short-circuited, an interrupt is sent to the microcomputer 36 from the speed detection control circuit 38 shown in FIG.

When the microcomputer 36 receives an interrupt from the speed detection control circuit 38, it performs the interrupt processing as shown by A in FIG. That is, in step 101, the time from the previous interrupt to the current interrupt is calculated, and in step 102, the speed of the printing section 20 is calculated. This result is stored in the memory table as the current printing speed in step 103. In this way, the microcomputer 36 calculates the speed of the printing section 20 every time an interrupt occurs, so the current speed is always stored in the memory table, and changes in the speed of the printing section 20 can be seen in detail. .

By the way, if printing data is being sent to the microcomputer 36 from a host device while the printing section 20 is moving, the microcomputer 36 performs the printing drive process shown in FIG. 7B. That is, in step 201, the data stored in the memory table is read to find out the current speed of the printing section 20. Next, in step 202, the heating element driving pulse width for the print head heating section 26 is set using whether printing was performed with the previous dot and the time interval from the previous dot to the current printing as parameters. In step 203, based on the speed of the printing section 20, when to send the next data drive pulse to the printing head heating section 26 through the printing head control driver 39 is calculated, and the driving timing of the printing head heating section 26 is set. Next, in step 204, the process waits until the drive timing setting time. By the way, if the interval between printed dots in the horizontal direction corresponds to the interval at which the brush 35B crosses the good conductor 34, the process in step 204 is not necessary, but normally the interval at which the brush 35B crosses the good conductor 34 is equal to the number of printed dots. In order to deal with this, the processing of step 204 becomes necessary. At step 205, the print head control driver 39 sends a heating element drive pulse to the print head heat generating section 26 to print on the paper 40. As for the necessity of the process in step 202, if the printing dot is driven, the printing head heating section 2
6 has increased, and the heating element driving pulse width may be short. Furthermore, since the way the temperature decreases differs depending on the speed of the printing section 20, the heating element drive pulse width is set in consideration of the speed of the printing section 20.

Next, a description will be given of an operation for changing the driving timing of the print head heat generating section 26 in response to a change in the speed of the printing section 20 to perform normal printing.
The part indicated by A in FIG. 8 shows the speed change of the printing section 20. That is, since the printing unit 20 is moved by hand, its speed 42 changes as shown in the figure. In the figure, I ₁ , I ₂ , and I ₃ indicate the timing at which the microcomputer 36 is interrupted due to a short circuit between the brushes 35A and 35B. Interrupt I ₁
There are T ₁ hours between and interrupt I ₂ , and T ₂ hours between interrupt I ₂ and interrupt I ₃ . Also, reference numeral 43 in the figure
44, 45, and 46 correspond to the timing of printing the dots A ₂₁ , A ₂₂ , A ₂₃ , and A ₂₄ at the lower left of the print A shown in FIG. 8B. Also, A in Figure 8B shows the state when A printing is performed normally.
This is an example in which the microcomputer 36 ideally changes the timing of print drive pulse generation in response to changes in the speed of the printing unit 20, and prints each dot forming A at the correct position. B shows an example in which the microcomputer 36 changes the print drive pulse generation timing relatively without error in response to changes in the speed of the printing unit 20, and prints dots. Example C shows an example in which the print A is shrunk because the print drive pulse generation timing is kept constant in response to changes in the speed of the print unit 20. In addition, in the figure, A ₁₁ , A ₂₁ , A ₃₁ are the first dots at the lower left of A, similarly A ₁₂ , A ₂₂ , A ₃₂ are the second dots at the lower left of A, and similarly A ₁₃ , A ₂₃ , A ₃₃ , _A14 , _A24 ,
A ₃₄ , A ₁₅ , A ₂₅ , and A ₃₅ indicate the 3rd, 4th, and 5th dots at the lower left of A, respectively. Furthermore, the symbol in the figure
d ₁ is the printing A shown in B for the printing A shown in A.
_d2 shows the error of the print A shown in C with respect to the print A shown in A.

8C shows the print drive pulse generation timing, 1 shows the timing when printing is performed in the example A of FIG. 8B, and 2 shows the printing timing in the example B. 1 indicates that the print drive pulse generation timing is delayed by the amount corresponding to the speed change of the print unit 20. That is, from the point where the normal printing drive pulse generation interval is a time, A ₁₃ is printed by delaying time a + b, and then by delaying time a + b + c.
By printing A ₁₄ , the speed of the printing section 20 is slowed down to prevent the print A from shrinking. The same goes for example (2), and the print drive pulse generation timing, which is normally a time interval, is changed to A ₂₄ after a + b' time.
is printed, and A ₂₅ is printed after a+b'+c' time.

Here, the distance at which the brushes 35A, 35B are short-circuited and an interrupt occurs in the microcomputer 36 is the distance between the interrupts I ₁ , I ₂ , I ₃ and the timings 43, 44,
45, it can be seen that an interrupt (speed detection of the printing section 20) occurs once every two dots. The printing section 20 is held by a person and moved from left to right, and at this time printing is performed on the paper 42. Now, as shown in the example of FIG.
The operation of normally printing A while changing will be described in more detail, but since the principle of operation of a thermal serial printer is already a well-known fact, it will be omitted. In order to obtain the correct shape of the print A despite the change in speed 42 as shown by A in FIG. 8B, the microcomputer 36
is the print head heating section 2 based on the change in speed 42.
6 may be driven through the print head control driver 29 at the timing shown in FIG. 8C (1). That is, the timing of driving the print head heating section 26 is delayed by b to print dot A ₁₃ in proportion to the slowing of the printing section 20, and is further delayed by b+c to print dot A ₁₄ . Correct print A is obtained. In other words, the microcomputer 36 generates a driving pulse to the print head heat generating section 26 to print when the print head heat generating section 26 comes to the correct position for printing. However, in this case, the speed detection of the printing unit 20 is horizontally
Because it is done once every dot,
Errors occur due to rapid speed changes in the printing section 20.

(2) in FIG. 8C shows a case where this error occurs. When the microcomputer 36 detects the interrupt _I2 at timing 44, the speed of the printing section 20 is calculated, the timing for printing the next dot _A23 is calculated, and _A23 will be printed after a time a. However, in reality, since the speed of the printing unit 20 is slow, printing should be performed after time a+b, and an error corresponding to time b occurs. Similarly, dot
_A24 has an error of (b+c-b') time.
By the way, the example C in FIG. 8B shows a case where the speed of the printing section 20 is not detected and printing is performed by always driving the printing head heat generating section 26 at a constant timing regardless of the speed. . In this case, the dots are arranged horizontally by d ₂ with respect to the normal printed character A, and the character A is shrunk and deformed. On the other hand, when the speed of the printing section 20 is detected and the drive timing of the printing head heating section 26 is changed accordingly, the error is d for the most ideal printing A. ₁ , indicating that the timing control of the print drive pulse has a great effect on the speed change of the print unit 20. It should be noted that if the interrupt timing is set in small increments, the error will be further reduced, and it will be possible to approach the ideal printing A shown in A.

Next, the operation of the printing unit 20 to start printing from a predetermined position on the paper 40 will be explained. FIG. 9 is a diagram showing an example in which print data sent from a host device is printed on a sheet 40 using a conventional printing device as shown in FIG. In this figure, CR ,
〓〓marks such as LF are not actually printed, but are called control codes. The printing device detects these control codes from the print data and
If it is LF, it will feed one line, if it is CR, it will return the print head to the left print start position, if it is TOF, it will feed the paper to the print start line of the next page, etc. As shown in the figure, ABCD will be placed on the nth line, and ABCD will be placed on the n+1 line.
Print EFGFH...etc.

FIG. 10 is a diagram showing a case in which the same print data as in FIG. 9 is printed by the printing unit 20 of this embodiment, and the printing unit 20 is manually moved along the ruler 41 as indicated by the arrow in the figure. on paper 40 by
Print ABCD etc. FIG. 11 is a diagram showing speed changes between the n-th line and the (n+2)-th line of the printing unit 20 shown in FIG. 10. The figure shows the point in time when printing started, and indicates the point in time when printing ended. Further, numerals 47 and 48 indicate the time when the speed of the printing section 20 becomes zero and the time when the printing section 20 starts to move again, and numeral 49 indicates the time when the printing section 20 is moving but no printing is being performed. indicates a period in which there is no
Figure 12 is a diagram showing the speed change of the printing unit 20 when the printing unit 20 temporarily stops while printing the nth line, and ABCD shown on the right side of the figure indicates the printing state at this time. It is something.

Print data is sent to the printing unit 20 through a cable 22 from a host device (not shown). That is, in the control circuit of Fig. 5, LF, LF ABCD CR
, LF EFGH CR , LF IJKL CR , LF
The MNOP TOP code is sent from the host device. Whether or not the control circuit receives these codes at once is determined by the capacity of the buffer for storing print data in the control circuit, but the capacity of the buffer does not matter here. Now, a case where the printing section 20 prints on the nth line as shown in FIG. 10 will be described. In this n-th line, the printing device 20 starts printing at a time point as shown in FIG. 11, and after printing ABCD, the microcomputer 36 of the control circuit detects CR and LF control codes and stops printing at that point. . Therefore, even though the control unit 20 is still moving during the subsequent period 49,
The next line of EFGH data is no longer printed. When the printing unit 20 completely stops at time 47 in FIG. 11 and starts moving again at time 48, the microcomputer 36 recognizes that it is printing the (n+1)th line and starts printing at the time.
Print EFGH and end printing at this point. Normally, the printing unit 20 is moved to the left start position SA marked by the ruler 41 in FIG. 10 between time points 47 and 48. Similarly, the (n+2)th line is printed. In addition, each line is always printed at the starting position SA.
Since the printing unit 20 is moved from the position, the printing position of each line can be aligned. FIG. 12 shows a case where the printing unit 20 once stops during printing of the nth line and moves again, and the microcomputer 3
6 detects that the speed of the printing section 20 is zero, it temporarily stops printing B, and when the printing section 20 starts moving again, it continues printing the rest of B, prints CD, and stops printing at that point.

In the above printing operation, the microcomputer 36 obtains speed information of the printing unit 20 from the speed detection control circuit 38 and performs the above control, and when the printing unit 20 reaches a predetermined speed, starts the printing operation and performs control. After detecting the code CR or LF, the operation of the printing unit 20 temporarily stops, and when it starts operating again, it recognizes a line feed, and if it detects that the printing unit 20 has stopped in the middle of printing, it stops printing at that point. Then, when the printing unit 20 starts moving again, control is performed to continue printing.

13A and 13B are flowcharts showing the processing when the printing unit 20 of the microcomputer 36 of FIG. 5 stops and the processing when the printing unit 20 starts moving. In the process of A, first step 301
At step 302, it is determined whether or not printing of the line concerned has been completed, and if it has been completed, the process proceeds to step 302, where data indicating completion is stored in the parameter table in the microcomputer 36, and the process is terminated.
If it is determined in step 301 that printing has not been completed, the process goes to step 303, stores data indicating that printing of that line is continuing in the parameter table in the microcomputer 36, and ends the process.

In the process B, first, in step 401, the microcomputer 36 reads its own parameter table and checks whether printing of the relevant line has been completed.
Judging by 402, if not completed, step
At 404, printing of the line is continued. If the printing has been completed, printing of the next line is started in step 405.
That is, by processing A and B, the operation on the n-th line in FIG. 11 and the operation on the n-th line in FIG. 12 can be performed separately.

According to this embodiment, a person holds the printing unit 20 in which the printing head heat generating unit 26, the speed detection roller 27, the IC ₃₀ constituting the control circuit, etc. are integrated into one unit, and scans the paper 40. At this time, in response to the speed change of the printing unit 20, the microcomputer 36 in the control circuit changes the drive timing of the print head heat generating unit 26 to print in the correct shape, and the microcomputer 36 prints by changing the drive timing of the print head heating unit 26. When a CR or LF code is detected from the print data from the host device, printing of that line is stopped even if the printing section 20 continues to move, and the microcomputer stops printing of that line even if the printing section 20 continues to move. Since we have adopted a printing device that recognizes that the printing unit 20 has moved to the beginning of the next line when it is detected and controls the printing of the next line, it is possible to omit the horizontal movement mechanism of the print head and the line feed mechanism of the paper. I can do it,
In particular, when printing on large-sized paper, printing can be performed simply by lengthening the scanning distance of the printing section 20 without increasing the size of the horizontal movement mechanism or line feed mechanism, making it extremely economical to print on large-sized paper. Printing can be performed, and the printing unit 20 can print each line at a predetermined position. Further, since the horizontal movement mechanism of the printing unit 20 and the paper line feed mechanism are omitted, power consumption can be reduced and almost no noise is generated.

In the above embodiment, a case has been described in which characters are printed in a dot structure, but it goes without saying that the printing apparatus of the present invention can also be applied to cases in which images such as figures are printed in a dot structure. Further, in the above embodiment, a case has been described in which the printing section 20 is directly grasped and moved by a human hand, but the same effect can be obtained even if the printing section 20 is moved indirectly by a human hand. or,
The same effect can be obtained by moving the paper or the like using a drive mechanism such as a pulse motor, and only by manually scanning the print area horizontally. Furthermore, the printing apparatus of the present invention can be applied to those having a thermal transfer type printing head, and the same effects can be obtained. Furthermore, in this embodiment, CR,
Although we have explained an example using LF, it is sufficient to define a control code other than the print code at the end of each line, and the code is not limited to the above code.

〔Effect of the invention〕

As described above, according to the printing device of the present invention,
A printing section that incorporates a printing head, a speed detector, and a control circuit is provided, and when the printing section is manually scanned over the paper, the printing head drive timing is changed according to the speed of the printing section and the paper is scanned. printed on,
In addition, when the microcomputer in the control circuit detects a CR or LF code from the print data from the host device, it controls the printing unit to stop printing that line even if the print unit continues to move, and also controls the speed to stop printing. The detector detects when the speed of the printing section once becomes zero, recognizes that the printing section has moved to the beginning of the next line, and then controls the printing of the next line to start. Also, there is an effect of printing on a large size paper at a low cost without increasing the size of the device, and there is an effect of printing at a predetermined position for each line.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a conventional printing device, FIG. 2 is a schematic diagram showing an embodiment of a printing section realizing the printing device of the present invention, and FIG. Enlarged view, Figure 4 is the internal configuration diagram of Figure 2, Figure 5
The figure is a block diagram showing an example of the control circuit formed in the IC shown in Fig. 4, Fig. 6 is a diagram showing the actual state of printing on paper using the printing section of this embodiment, and Fig. Figure 7A is a flow chart of the print drive process of the microcomputer shown in Figure 5, Figure 7B
5 is a flowchart of the interrupt processing of the microcomputer shown in FIG. 5, FIG. 8 is a speed change characteristic diagram of the printing section of this embodiment, a printing state diagram of print A, a timing diagram of print head drive pulses, and FIG. 9 is a diagram showing a state in which print data is printed on paper using the printing device shown in FIG. 1, FIG. 10 is a diagram showing a state in which print data is printed on paper using the printing unit 20 of this embodiment, FIG. 11 is a diagram showing the speed change of the printing unit 20 in the nth to n+1 lines, FIG. 12 is a speed change diagram showing the state where the printing unit 20 has stopped once in the middle of printing, and FIGS. 13A and B are micrographs. FIG. 4 is a process flowchart when the printing unit is stopped and when the printing unit starts moving in the computer 36. FIG. 20...Printing section, 22...Cable, 26...
Print head heating section, 27...Detection roller, 30
...IC, 35A, 35B...Brush, 36...
Microcomputer, 38... Speed detection control circuit, 39... Print head control driver.

Claims (1)

[Claims] 1 A print head, a speed detector that detects the moving speed of the print head, and a control circuit that takes in the speed of the print head and controls the print drive pulse width and the drive timing of the print head are integrated into one unit. When the printing section is configured and the printing section is manually scanned over the paper, the control circuit scans the printing head on the paper while changing the drive timing of the printing head in accordance with the speed of the printing head (printing section). It performs printing control according to print data sent from the host device, and when a carriage return or line feed control code is detected from the print data, printing of the relevant line is performed even if the printing section is moving. furthermore, the speed detector detects that the speed of the printing section once becomes zero and starts moving again, so that the line feed of the printing section is recognized,
A printing device characterized in that the printing device performs control to start printing the next line when the speed of the printing section reaches a predetermined value.