JP2907803B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer, and more particularly, to a printer capable of realizing high throughput.

2. Description of the Related Art A high throughput is sometimes required for a printer in order to take advantage of the high speed of a main unit such as a computer. This high throughput can be achieved not only from the viewpoint of shortening the time actually being printed by the print head, but also by starting preparation of printing of a certain document and then manually obtaining a completed printed document. It is necessary to consider this as a reduction in the overall printing time before the printing.

[0003]

2. Description of the Related Art One of the factors affecting the throughput is as follows.
There is control to prevent overheating of the printhead. That is,
In the impact type dot matrix printer, the print head type (electromagnetic type, piezoelectric type) and carrier type (single head, multi head, shuttle head)
Regardless, a thermal sensor is installed inside or outside the printhead to prevent the printhead from overheating, and control is performed based on the temperature information. A general control method is to use one line (1
This is a divisional printing method in which a line is printed a plurality of times.

FIG. 20 shows a method of printing one line divided into two times. The central processing unit (CPU) or the like of the printer reads the detection signal from the thermal sensor (S101) and checks whether the value exceeds a predetermined limit temperature (S102).

If it exceeds, the carrier motor is started for printing (S103), printing is performed for 1/2 line first (S104), and the carrier motor is stopped once (S1).
05), the carrier motor is started again (S106), printing is performed for the remaining half line (S107), and then the carrier motor is stopped (S108).

If the temperature has not exceeded the limit temperature in S102, the carrier motor is started (S109), printing is performed for the one line (S110), and the carrier motor is stopped (S111).

Thereafter, it is determined whether or not printing is completed (S11).
2) If it is not the end, after performing a line feed (S113),
S101 and subsequent steps are repeated. In the case of termination, the processing ends. Another factor that affects the throughput is the control for printing ruled line characters, especially for the interpolation printing. That is, as shown in FIG. 21, if a normal line break is repeated, a gap is generated between lines when a vertical ruled line is printed, and it is difficult to say that the ruled line is a continuous ruled line. Therefore, it is necessary to perform interpolation printing for separately printing the line spacing part (interpolation part) of a normal line feed.

FIG. 22 shows a process of printing ruled line characters. First, normal printing is performed for a certain line (S12).
1) Check for the presence or absence of ruled line characters (S122). If there is no print, the printing is terminated as it is. If there is, a line feed corresponding to the height of the head is performed to position the print head at the interpolation unit (S123), and printing by the interpolation unit is performed (S12).
4). Thus, for example, the normal portion of the Nth line of the vertical ruled line is S
It is printed at 121, and the interpolator below it is printed at S124.

Another factor that affects the throughput is the skew check time in terms of the total printing time. That is, as shown in FIG. 23, the conventional printer has only a fixed paper sensor.
The printer body cannot measure the skew of the paper (the inclination of the printing direction with respect to the side of the paper due to the paper being fed obliquely). Therefore, the skew is measured by an operator as shown in FIG.

In FIG. 24, a sheet for skew measurement is fed (S131), a specific skew check pattern (usually a horizontal ruled line) is printed thereon (S132), and the sheet is discharged (S133). About this paper,
The operator visually determines (or uses a predetermined measuring device) whether or not there is a skew and the degree of the skew.

Another factor that affects the throughput is the time for printing position adjustment particularly when a continuous paper is pulled by a continuous tractor and used (in the case of a tensile continuous paper). That is, in this case, as shown in FIG. 25, the operator visually adjusts the print position using a line feed switch (switch) or a sheet feed switch. This is because the continuous tractor does not have a positioning function.

In FIG. 25, when the operator presses the paper set switch (S141), the path of the printer is opened and the continuous paper can be inserted. Then, the operator inserts the continuous form paper and puts it on the continuous form tractor (S142).
Thereafter, the operator performs print position alignment using the line feed SW and the sheet feed SW (S143), and when there is a position, puts the printer online and waits for printing (S144).

[0013]

According to the processing shown in FIG. 20, there is a problem that the throughput at the time of divided printing is extremely deteriorated.

For example, when it is determined that one line is divided into two as shown in FIG. 20, two divided printings are uniformly performed regardless of the printing amount in that line. Therefore, even if the line is a low-duty (small number of characters) line, printing is performed twice. For this reason, if the number of characters in the line is one and the number of characters does not exceed the limit temperature even when printing is performed, the throughput (for the line) is reduced to half by divided printing. Resulting in.

Further, according to the processing shown in FIG. 22, there is a problem that the throughput when printing ruled line characters is deteriorated. That is, according to the processing of FIG.
In the case of 122), printing of the interpolation unit (S124) is always performed. Therefore, the total printing time is
One line is twice as large as the case without the interpolation unit.

Incidentally, ruled line characters include "@", "@",
There are patterns (characters) such as “┘” and “┴”. In these cases, only normal printing is sufficient, and printing of the lower interpolation unit is not required. This is because the vertical ruled lines are not continuous downward.

In the case of such a pattern as well, the printing of the lower interpolation section (which is to be done by printing a blank line) which is originally unnecessary is always performed. This is, in terms of throughput,
This means that the throughput is degraded by the amount of interpolation printing even on the lower side of the bottom line.

Further, according to the procedure shown in FIG. 24, there is a problem that the throughput is deteriorated from the viewpoint of shortening the total printing time since the operator needs to intervene.

That is, since the printer does not have an automatic skew check function, printing is actually performed (S132), and the result must be visually determined (S13).
4). For this reason, a considerable amount of time is required for a skew check before starting printing. Therefore, the total printing time including the time of the skew check becomes long, and the throughput is deteriorated.

According to this procedure, an operator is required to intervene in each step, which is very troublesome for the operator. In addition, there is also a problem that the printing is actually wasted, so that the paper is wasted. In addition, since the skew is missed due to visual observation, printing may be performed as it is.

Further, according to the procedure shown in FIG. 25, since the operator needs to visually adjust the printing position, there is a problem that the throughput is deteriorated in terms of shortening the overall printing time.

That is, since the continuous tractor does not have a positioning function, the operator must perform positioning by operating a switch (S143). For this reason, a considerable amount of time is required for alignment before starting printing. Therefore, the total printing time including this time becomes long, and the throughput is deteriorated.

According to this procedure, since the printing position is adjusted visually by operating the switch, the operation is very troublesome for the operator. In addition, since the printing position is displaced due to visual observation, printing may be performed as it is.

An object of the present invention is to provide a printer capable of improving the throughput. Also,
SUMMARY OF THE INVENTION An object of the present invention is to provide a printer capable of automatically performing a skew check in the printer.

[0025]

FIG. 1 is a block diagram showing the principle of the present invention, and shows a printer according to the present invention. In this printer, the temperature of the print head 7 is detected by the thermal sensor 6,
It has a function of controlling printing by the print head 7 based on this detection output. For this purpose, the detection output of the thermal sensor 6 is used as a control amount, and the difference between a predetermined limit temperature and the detection output is used as a deviation. And a print amount processing unit 2 that performs proportional control using the number of print dots per unit time as an operation amount.

The print amount processing unit 2 obtains the deviation, adds a predetermined constant to a product of the deviation and a predetermined proportional constant, obtains the operation amount, obtains the total number of print dots in one line, The operation time and the carrier pause time of the line are determined from the operation amount and the total number of print dots.

Further, this printer has a function of performing printing of an interpolation unit when a ruled line character exists.
The image processing apparatus includes a ruled line interpolation processing unit 3 that determines whether or not printing by the interpolation unit is necessary according to the pattern of the ruled line characters.

The ruled line interpolation processing unit 3 checks whether there is data to be printed on the last dot in the vertical direction of the ruled line character pattern, and if there is, prints the interpolation unit. The printing of the copy is omitted.

This printer has a function of automatically obtaining the skew of the paper fed by a predetermined motor. For this purpose, a sensor for detecting the position of the paper is provided. And a skew processing unit 4 for obtaining a skew.

The skew processing section 4 moves the movable sensor 15 in a predetermined direction to detect a sheet at one end in the width direction of the sheet, and obtains a predetermined motor rotation angle at the time of this detection.
At the other end in the width direction of the sheet, the rotation angle of a predetermined motor when the sheet is detected by the movable sensor 15 or another sensor (14) is obtained, and the skew is obtained from the difference between the two rotation angles.

Further, the printer has a function of pulling the continuous form paper by the continuous form tractor 30 to convey and print the continuous form paper. Further, at the time of this printing, the continuous form paper is automatically placed at a predetermined position. It has the function of positioning.

For this purpose, the printer includes a sensor 34 for detecting the position of the continuous form paper, the non-volatile memory 16 for storing a predetermined position of the continuous form paper, and the position of the continuous form paper applied to the continuous form tractor 30. To a predetermined position.

First, the tension continuous sheet registration processing unit 5 obtains a predetermined position of the continuous form paper using the detection output of the sensor 34 and stores it in the non-volatile memory 16. When the continuous form paper is placed on the non-volatile memory 16, the position of the continuous form paper is adjusted using the detection output of the sensor 34.

[0034]

The print amount processing unit 2 determines the number of print dots per unit time (operation amount) by the proportional integration control, and prints the print head 7.
Is varied according to the temperature of This operation amount can be changed by reducing the moving speed of the carrier or providing a rest time when the carrier stops. It can be said that the manipulated variable is a MAX duty that does not reach the limit temperature obtained by the current deviation. Therefore, in the present invention,
Even in the case of a low-duty line, the printing does not always enter the divisional printing, and the operation amount is set to the number of printing dots per unit time. Therefore, a decrease in throughput can be prevented, and the overall throughput can be improved.

The ruled line interpolation processing unit 3 omits printing by the interpolation unit when there is no print data in the last dot in the vertical direction, such as “─” or “└”, in the ruled line character pattern.
Therefore, when the interpolation to the lower side is unnecessary, this can be omitted, so that the throughput can be improved by that much, and on the other hand, the vertical ruled line can be prevented from becoming a broken line.

By using the movable sensor 15, the skew processing section 4 can detect the sheet at one end and the other end in the width direction of the sheet. The position of the sheet at the time of detection is known from the rotation angle of the motor at the time of this detection, and the skew can be obtained from this.

Accordingly, since the skew check can be automatically performed in the printer, the time for the skew check can be greatly reduced, and the throughput can be improved in terms of the total printing time. In addition, since the need for operator intervention is eliminated, the burden on the operator can be reduced.
Further, since printing for skew check can be omitted, waste of paper can be prevented. Further, since no skew can be detected, it is possible to prevent printing with skew.

When the operator first aligns the continuous form paper at a predetermined position, the tension serializer registration processing unit 5 stores this in the nonvolatile memory 16. The next time the operator places the continuous form paper on the continuous form tractor 30, the position of the continuous form paper is adjusted to the previously stored predetermined position.

Therefore, the operator only needs to perform the positioning once, and the printer automatically performs the positioning from the next time, so that the time required for the positioning can be greatly reduced and the total printing time can be reduced. Throughput can be improved. Further, the burden on the operator can be reduced, and the occurrence of misalignment can be prevented.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an outline of a printer will be described with reference to FIG. 2 for convenience. In FIG. 2, the dashed line indicates the flow of the cut, and the dotted line indicates the flow of the continuous form.

The cut sheet is prepared in the hopper 22, fed under the print head 7, printed, and then discharged to the stacker 29. This printer uses paper transport processing.
It has two drive systems or motors. Paper feed motor 12
Drives the pick roller 23 and the inserter roller 24. The LF (line feed) motor 10 drives a platen 25, an inserter roller 27, a discharge roller 28 (and a continuous tractor 30).

The cut sheet is picked up by a pick roller 23 driven by the paper feed motor 12 and sent to an inserter roller 24. Then, the paper is fed under the print head 7 (between the print head 7 and the platen 25) by the inserter roller 24. Further, printing is performed by the print head 7. At this time, a cut line feed is started in line with the printing timing according to the platen 25 and the two pairs of rollers 24 and 27 driven by the LF motor 10 and the paper feeding motor 12. After the printing is completed, the cut sheet is discharged from the pair of discharge rollers 28 to the stacker 29 via the pair of inserter rollers 27. The inserter roller 27 and the discharge roller 28 are driven by the LF motor 10.

For example, in the case of the press-in continuous mode, the continuous form tractor 3 driven by the LF motor 10 is used.
From 0, it is sent to the platen 25 through the inserter roller 27. Then, after printing by the print head 7, the print head 7 discharges the paper by the inserter roller 24. Therefore, in the case of the press-in continuous mode, the continuous form is transported in the direction of arrow A in the figure.
At this point, the movement is in the direction opposite to the direction of the single sheet conveyed from the hopper 22 to the stacker 29.

In the case of the pulling continuous mode, the continuous form is conveyed in the reverse direction along the same route as the press continuous mode. That is, it is transported in the direction of arrow B in the figure. In the case of the pulling continuous mode, the continuous form is supplied to the continuous tractor 3 by the operator.
It is transported by being multiplied by zero and pulled by the continuous tractor 30.

Paper sensor 3 for detecting the position of the paper
1 to 34 are provided at positions as shown. The paper sensor 31 is provided immediately after the pick roller 23, and mainly detects whether there is no paper in the hopper or whether a picked-up cut sheet is correctly sent (without occurrence of paper jam or the like).

The paper sensors 32 and 33 are provided immediately before and immediately after the inserter roller 24, respectively, and detect the position of a cut sheet and the position of a continuous form. Note that the paper sensor 33 is
As shown, it is provided between the inserter roller 24 and the platen 25.

The paper sensor (tractor sensor) 34 is provided at an intermediate position of the continuous tractor 30 and is mainly used for detecting absence of paper in the continuous paper. The paper sensors 31 to 34 are, for example, reflection type sensors. When the leading edge of the paper crosses, it detects this and sends a high-level signal "1" (or a low-level signal) instead of the low-level signal "0". When the trailing edge of the sheet crosses, this is detected, and a low-level signal (or high-level signal) is transmitted instead of the high-level signal.

A thermal sensor 6 for detecting the temperature of the print head (print head) 7 is provided so as to be attached to the print head 7. The thermal sensor 6 is composed of, for example, a thermistor.

Next, the outline of the printer of this embodiment will be further described with reference to FIG. In FIG. 3, a central processing unit (hereinafter, CPU) 42 includes a program ROM 40
By executing various processing programs stored in the printer, various processes such as paper feeding and printing in the printer are performed. To this end, the CPU 42 transmits and receives data to and from the main unit 17 such as a computer (see FIG. 1) via the input / output circuit 44, and receives, for example, a paper feed command and print data. The print data is stored in the RAM 41. Also, CP
U42 is connected via the input / output circuit 44 to the console 18 (FIG. 1).
Data). On the console 18,
Various operation switches such as a paper set switch (SW) are provided.

When the CPU 42 receives a paper feed command or the like, it starts a timer 43 and executes the CPU 43 at a predetermined cycle.
An interrupt to 42 is generated, and the motor drive circuit 38 necessary for executing each command is driven. As a result, the carrier motor 35 shown is driven to drive the carrier on which the print head 7 is mounted to move the carrier, and the paper feeding motor 12 and the LF motor 10 are driven to perform paper feeding and line feed. Let Further, the print head drive circuit 37 is driven to strike the print head 7 to perform necessary printing. As print data such as a print position and print contents, data stored in the RAM 41 is read out and used by the CPU 42.

The thermal sensor 6 provided on the print head 7 is connected in series with the dividing resistor, and is connected between the power supply potential Vcc and the ground potential. As a result, a change in the resistance value of the thermal sensor 6 according to a change in the temperature of the print head 7 is detected as a change in the voltage value, and is input to the AD converter 36. The CPU 42 stores the detection output of the thermal sensor 6 converted into a digital value by the AD converter in the RAM 41 and uses it in a predetermined process.

The fixed sensor 14 and the movable sensor 15 form a pair and constitute paper sensors 31 to 34. Signals from the fixed sensor 14 and the movable sensor 15 are input to a sensor input processing circuit 39. The CPU 42 controls each of the sensors 14 and 1 that have been subjected to predetermined processing by the sensor input processing circuit 39.
The detection output of No. 5 is stored in the RAM 41 and used for predetermined processing.

The nonvolatile memory 16 is, for example, an EEPROM.
The CPU 42 writes data indicating a predetermined position of a sheet (continuous sheet). Note that the nonvolatile memory 16 may be an external storage device such as a magnetic disk.

Next, the printer of FIG. 1 will be described with reference to FIGS. In this description, FIGS. 4 to 19 are appropriately referred to. In FIG. 1, a processing device 1 includes a CP.
U42, a program ROM 40 and an RA for storing data.
And a memory including M41 and the like. A console 18 and a main unit 17 are connected to the processing device 1. The console 18 is used for inputting instructions for processing,
This is sent to the processing device 1. The main unit 17 is a printer,
That is, it requests the processing device 1 for a printing process and sends a paper feed command or the like.

The print controller 9 controls the print head 7, the CR motor 8, and the like. The CR motor 8 is a motor for driving the carrier on which the print head 7 is mounted.
The line feed control unit 11 controls the LF motor 10 and performs a line feed in accordance with print timing. The paper feed controller 13 controls the paper feed motor 12 to feed paper. These controls are performed in accordance with instructions from the processing device 1.

The processing device 1 controls the entire printer.
For example, when a paper feed command is received from the main unit 17,
By driving the paper feed motor 12 via the paper feed control unit 13,
The cut sheet is fed to a position below the print head 7. When the line feed command is received, the LF motor 10 is driven via the line feed control unit 11 to perform a line feed up to the print position. When a print command is received, the CR motor 8 is driven via the print control unit 9 to move the carrier and perform printing by the print head 7.

The processor 1 controls the amount of printing in this printing process to prevent the temperature of the print head 7 from exceeding the limit temperature, and to omit interpolation printing for ruled line characters. Further, the processing device 1 checks for the presence or absence of skew prior to the sheet feeding process. Further, the processing apparatus 1 performs the alignment of the fed continuous paper prior to the printing processing in the tensile continuous paper mode.

The printing amount is controlled by the printing amount processing unit 2. The print amount processing unit 2 includes a CPU 42 and a program ROM 40
This is realized by the above print amount control processing program.
Hereinafter, the processing performed by the print amount processing unit 2 will be described with reference to FIGS.

The print amount processing unit 2 controls the operation amount (number of print dots / print operation time) U by the equation U = K _p · e + a. Here, _Kp is a proportional constant, e is a deviation, and a is a constant. The deviation e is obtained by e = (limit temperature) − (current temperature of the print head 7).

The limit temperature is predetermined as a characteristic of the printer. The current temperature of the print head 7 is obtained from the detection output of the thermal sensor 6. For example, a table prepared in advance is searched using the detection output (output of the AD converter 36), and a temperature corresponding to the detection output (voltage value) is obtained. Thus, the deviation e is obtained. The proportional constant _Kp and the constant a are empirically obtained in advance as characteristics of the printer. Therefore, the operation amount U is uniquely determined according to the detection output of the thermal sensor 6.

For the operation amount U, the number of print dots (the total number of print dots in one line) is obtained from the print data on the RAM 41. Therefore, the printing operation time is obtained from these. The printing operation time is determined by the operation time t of the carrier in one line,
This is the sum with the rest time tα of the carrier. The operation time t is determined as one of the performances of the printer. That is, the operation time t when printing all the characters in one line is predetermined. Therefore, the pause time tα is determined from this.

As described above, the processing performed by the print amount processing unit 2 uses the detection output of the thermal sensor 6 to calculate the pause time tα.
The temperature of the print head 7 is adjusted by expanding / contracting.

As a result of this processing, the temperature of the print head 7 (the temperature of the thermal sensor 6) approaches the limit temperature as the printing time elapses, as shown by the alternate long and short dash line in FIG. Keep the temperature. That is, the temperature is controlled based on the operation amount U so that the temperature changes over time. As a result, the number of printing lines increases substantially in proportion to the printing time, as indicated by the dashed line in FIG.

In addition, as shown by the solid line in FIG. 4, conventionally, control is performed to wait for the temperature to decrease from the limit temperature to the recovery temperature by divisional printing. As a result, as shown by the solid line in FIG. The relationship with time is not proportional, and the printing time increases and the number of printing lines (throughput) decreases.

The control of the print amount will be specifically described with reference to FIGS. One character is 24 dots (vertical) x 24
Consider a printer that can print 90 characters per line for dots (horizontal) characters. For simplicity, only one printing speed is assumed.

Further, as shown in FIG. 6, the acceleration time of the carrier is 100 mS, the printing time of 90 characters is 720 mS (accordingly, 8 mS for one character), and the deceleration time of the carrier is 100 mS.
mS, and the line feed time is 80 mS. Therefore, the operation time for printing all 90 characters is 1 second.

In such a printer, the temperature (proportional control start temperature) T at which processing by the print amount processing unit 2 is started
_p is 150 ° C, limit temperature T _max is 180 ° C, proportionality constant K
_{Let p} be 216 and the constant a be 6480.

Under the above conditions, the character pattern (A) or (B) shown in FIG. 7 is printed. The patterns (A) and (B) are patterns in which a vertical line having a width of 6 dots and 3 dots, respectively, is printed as one character. Therefore, the print amount of (A) is twice as large as (B).

When each constant is applied to the above-mentioned equation of the manipulated variable U,

[0070]

(Equation 1)

Is obtained. Consider the pattern (B). Assume that the current temperature T of the print head 7 becomes 150 ° C. when 90 characters (all one line) are printed in the pattern (B). In response,

[0072]

(Equation 2)

## EQU1 ## thereby, tα is obtained. Here, tα = −
Since it is 0.5, it can be considered that tα = 0. Therefore, the next line is printed immediately after the line feed. That is, 90 characters are printed in the pattern of (B). As a result, the temperature T becomes 180
C. In response,

[0074]

(Equation 3)

As a result, tα = 0 is obtained. Therefore, the next line is printed immediately after the line feed. That is, 90 characters are printed in the pattern of (B). As a result, the temperature T is assumed to be 190 ° C. In response,

[0076]

(Equation 4)

As a result, tα = 0.5 is obtained. Therefore, after the line feed, the carrier is stopped for 0.5 seconds, and then the line is printed. As a result, while the temperature T is set to 180 ° C. or lower as a result, the throughput is higher than in the case of performing the divided printing.

Next, the pattern (A) will be considered.
Assume that the temperature T becomes 150 ° C. when 90 characters are printed on the pattern of FIG. In response,

[0079]

(Equation 5)

As a result, tα = 0 is obtained. Therefore, the next line is printed immediately after the line feed. That is, the pattern of FIG.
Prints 0 characters. As a result, it is assumed that the temperature T becomes 180 ° C. In response,

[0081]

(Equation 6)

As a result, tα = 1 is obtained. Therefore, after the line feed, the carrier is stopped for one second, and then the line is printed. On the other hand, if the pattern of (A) is printed with only 45 characters and the temperature T is 180 ° C. at this time,

[0083]

(Equation 7)

As a result, tα = 0.36 is obtained. The operation time t is also determined by the print data (the number of characters). Therefore,
After a line feed, the carrier is stopped for 0.36 seconds, and then the line is printed. This results in a temperature T of 180
° C or lower, but the throughput is higher than in the case of performing divided printing. From the comparison between this case (printing of 45 characters) and the printing of 90 characters described above, if the number of characters in one line is small, the carrier stop time can be shortened.
The effect of improving the throughput is great.

FIG. 8 is a flowchart showing a print amount control process performed by the print amount processing unit 2. When activated, the detection output (temperature T) of the thermal sensor 6 is read (S1), and it is checked whether the temperature T is _{equal to} or higher than the proportional control start temperature Tp (S2). If T ≧ T _p , the deviation e is determined (S3), the manipulated variable U is determined (S4),
Obtain the total number of print dots in one line from the print data (S
5) Obtain the operation time t for one line from the print data (S
6) The pause time tα is obtained from the above (S7).

It is checked whether or not the obtained pause time tα is "0" or more (S8). If tα ≧ 0, tα = 0 is set (S9). Similarly, if T ≧ T _p is not satisfied in S2, tα = 0 is set in S9.

Next, the CR motor 8 is started (S10),
When the speed becomes constant, the printing process is performed in accordance with the print data (S11), the CR motor 8 is stopped (S12), and the elapse of the pause time tα is waited (S13). If tα = 0, S13 is substantially omitted.

Next, it is checked whether or not printing is completed (S14). If the printing is completed, the process is terminated. If not, a line feed is performed (S15), and S1 and subsequent steps are repeated. The ruled line interpolation is controlled by the ruled line interpolation processing unit 3. The ruled line interpolation processing unit 3 includes a CPU 4
2 and a ruled line interpolation processing program on the program ROM 40. The processing performed by the ruled line interpolation processing unit 3 will be described below with reference to FIGS.

The ruled line interpolation processing unit 3 searches the print data in the RAM 41 to check for the presence or absence of a ruled line character, and if so, further examines the pattern. Determines whether printing is required.

As shown in FIG. 9, when the ruled line character is a character pattern such as "+" (a character pattern that is continuous in the vertical direction), data to be printed always exists in the last dot in the vertical direction. In the case shown, one character is 24 dots (vertical) x
24 dots (horizontal), the last dot in the vertical direction,
That is, print data always exists at the 24th dot.

On the other hand, if the ruled line character is a character pattern such as "@", there is no data to be printed in the last dot (the 24th dot) in the vertical direction, needless to say.

Therefore, the ruled line interpolation processing unit 3 checks whether or not there is data to be printed in the last dot in the vertical direction of the ruled line character in the print data. , And if there is no interpolation printing, the lower interpolation printing is omitted.

In FIG. 9, "+" portion (print portion)
Is set to "1" (high level), and the remaining blank (non-printed) data is set to "0" (low level). Therefore, in this case, the existence of data to be printed can be determined by checking whether or not the data of the 24th dot is all “0” (all “0”).

In this embodiment, regardless of whether interpolation printing is omitted or not, if a ruled line character is present, a line feed corresponding to the height of the print head 7 (see FIG. 21) is performed after normal printing. This is for the following reason.

As shown in FIG. 10, the position of the print head 7 after the end of the normal printing portion of the ruled line character exists in the interpolation portion since the presence or absence of the printing of the interpolation portion has not been conventionally recognized. ). At this time, if there is a print command of character data "ABC", the character "ABC" is printed on the interpolation unit. This is used, for example, as a subscript.

On the other hand, if the printing of the interpolation unit is omitted according to the present embodiment, and if a line feed for the height of the print head 7 is not performed, the print head 7 after the end of the normal printing portion of the ruled line character is obtained. Is present in the normal printing portion as it is (right side in the figure). At this time, if the character data "ABC" is printed, the character "ABC" is printed in the normal printing portion.

Therefore, compatibility with a conventional printer cannot be maintained as it is, and this burdens the user. Therefore, as described above, a line feed corresponding to the height of the print head 7 after normal printing is always performed.

FIG. 11 shows a ruled line interpolation processing flow performed by the ruled line interpolation processing unit 3. Upon receiving the print data, the normal print portion of the print line is printed (S21), and the presence or absence of a ruled line character is checked (S22).

If there is no ruled line character, the process ends. If there is a ruled line character, a line feed corresponding to the height of the print head 7 is performed (S23), and then the interpolation necessary flag is cleared (S2).
4). The above is the pre-processing. The interpolation necessary flag is a flag of the ruled line interpolation processing unit 3 and uses a predetermined bit of a predetermined register of the CPU 42 (or a predetermined bit of a predetermined area of the RAM 41).

Next, it is checked in order from the first character of the print data whether it is a ruled line character (S25). If the character is a ruled line character, a pattern of the ruled line character is searched (S26), and printing should be performed on the last dot in the vertical direction. Check whether there is data (S2
7).

If there is data to be printed, the print data is expanded in a predetermined area on the print dot line buffer by the print pattern of the interpolation section (S28), an interpolation necessary flag is set (S29), and printing is performed. A part of the RAM 41 is used as the dot line buffer for use.

On the other hand, if it is determined in S25 that the character is not a ruled line character, S26 to S29 are omitted. If it is determined in S27 that there is no data to be printed in the last dot (all "0"),
28 and S29 are omitted. Therefore, in these cases,
The interpolation required flag remains cleared (not set).

Next, it is checked whether the last character of the print line has been searched (S30). If not, the process from S25 is repeated. If the search has been completed, it is checked whether the interpolation necessary flag is set (S31).

If it is set, the interpolation section is printed (S32) and the process is terminated. If not set, S32 is omitted and the process ends. Therefore, even if there is a ruled line character in the print line, if there is no data to be printed in the last dot in all the ruled line characters, the process proceeds to S32
The printing of the interpolation unit can be omitted by omitting, and the throughput can be improved accordingly.

The skew is detected by the skew processing unit 4. The skew processing unit 4 includes a CPU 42 and a program R
This is realized by a skew processing program on the OM 40. Hereinafter, the processing performed by the skew processing unit 4 will be described with reference to FIGS.

The skew processing section 4 calculates the skew based on the detection outputs of the fixed sensor 14 and the movable sensor 15. For this reason, the fixed sensor 14 and the movable sensor 15 form a set, and the sheet sensor 33 (or the sheet sensor 31 or 3) is used.
2) and the paper sensor 34. The former is used to detect the skew of a single form and a continuous form (in the tensile continuous mode), and the latter is used to detect the skew of the continuous form (in the push continuous mode).

As shown in FIG. 12, the fixed sensor 14 is fixed at a position slightly inside the left end of the sheet, for example. The movable sensor 15 is provided so as to be movable in the width direction of the paper, that is, in the printing direction (a direction parallel to the moving direction of the carrier), and is moved to a position slightly inside the right end of the paper in advance before the paper is fed. Is done. This movement is performed by the skew processing unit 4 corresponding to, for example, a paper feed command.

When the paper is fed in the paper feeding direction and the leading end thereof crosses the fixed sensor 14, the fixed sensor 14 detects this. At the time of this detection, the skew processing unit 4 controls the motor (for example, the paper feeding motor 1) that is driven to feed the paper.
The rotation angle in 2) is checked, and this is stored in the RAM 41.

Here, the paper feeding motor 12 and the like are composed of a pulse motor (or a DC servo motor) and are driven by sequentially changing the voltage (excitation phase) applied to each pole. Therefore, the excitation phase at the time of the detection is checked and detected.
The excitation phase can be easily obtained by checking the state of the motor drive circuit 38 corresponding to the motor.

Similarly, the excitation phase (rotation angle) of the paper feed motor 12 when the paper crosses the movable sensor 15 is also determined by the RAM 41.
Is stored. For convenience, the rotation angle when detecting the left end of the sheet is referred to as the left end rotation angle, and the rotation angle when detecting the right end is referred to as the right end rotation angle.

The skew processing section 4 checks the difference between the left end and right end rotation angles on the RAM 41 to determine the skew. That is,
If there is no skew, the difference between them is "0". vice versa,
If there is any difference between the two, it is known that skew exists.

Here, the printer increments the excitation phase several tens of times for a line feed of one line (for example, 1/6 inch). Therefore, according to the present embodiment, the skew can be detected with extremely high accuracy of an accuracy of several tenths of one row.

Further, according to this embodiment, it is not necessary to print a skew check pattern, and the procedure can be shortened. Since only the leading edge of the paper is detected, printed paper can be used.
Also, the same paper can be used a plurality of times, thereby saving paper.
Further, since the same paper can be used a plurality of times, the phenomenon can be reproduced on the paper on which the skew has occurred. Further, since skew can be detected at the time of paper feeding, it is possible to return an error to the main unit 17 to interrupt the job and feed the paper again.

The example shown in FIG. 12 is an example in which the skew is obtained by using the fixed sensor 14 and the movable sensor 15 as a set, and the skew is similarly obtained by using only one or two movable sensors 15. Can be requested.

FIG. 13 shows an example of skew detection using only one movable sensor 15. In the case of FIG. 13A, since there is only one movable sensor 15, the sheet is moved to a position slightly inside, for example, the left end of the sheet before feeding the sheet. Then, first, the sheet is moved to the movable sensor 1 at this position.
When crossing 5, calculate the left end rotation angle.

Thereafter, the movable sensor 15 is sequentially moved by a predetermined distance in the paper feeding direction and the printing direction (or vice versa) to a position slightly inside the right end of the paper.
When the paper crosses the movable sensor 15 at this position, the right end rotation angle is obtained.

In this case, the skew is obtained by, for example, subtracting the left-end rotation angle and the distance moved by the movable sensor 15 in the sheet feeding direction (the corresponding rotation angle) from the right-end rotation angle. Since the moving distance of the movable sensor 15 in the paper feeding direction can be accurately determined in advance, it does not affect the skew detection.

FIG. 13B shows an example in which the moving direction of the movable sensor 15 is oblique to the printing direction (and the paper feeding direction) as shown. In this case, since the moving direction of the movable sensor 15 is one direction, the configuration for the movement can be simplified. FIG. 13 shows skew detection.
This is the same as the case (A).

FIG. 14 shows an example in which the type of each sheet is automatically identified when a sheet of a special shape such as an envelope is fed as a sheet (single sheet). In this case, the left end and the center of the sheet (in the case of FIG. 14A) or the left end and the right end (FIG.
(B)), the left edge of the paper is detected,
Find the difference. For this reason, a unique step is provided in advance on paper such as an envelope. Therefore, by detecting this difference, the type of paper such as an envelope can be automatically identified. Note that the value of the skew is usually sufficiently small compared to the level difference of the sheet and can be ignored, and thus does not affect the identification of the sheet.

In the example of FIG. 14, the fixed sensor 14 and the movable sensor 15 are used as one set.
Only one or two movable sensors 15 can be used. FIGS. 15 and 16 show a skew detection processing flow performed by the skew processing unit 4. In particular, FIG. 15 shows a processing flow in the case of FIG. 12, and FIG. 16 shows a processing flow in the case of FIG.

In FIG. 15, when a paper feed command is received, the movable sensor 15 is moved by a predetermined distance so as to be located slightly inside the right end of the paper (S41), and then the paper is fed (S42).

When the sheet is detected by the fixed sensor 14 and the movable sensor 15, the rotation angle of the paper feed motor 12 is obtained (S43), and the skew is calculated from the difference between the two rotation angles (S44).

In FIG. 16, when a paper feed command is received, the movable sensor 15 is moved to a position slightly inside the left end of the paper (S51), and the paper is fed (S5).
2). Then, the rotation angle of the paper feed motor 12 when the paper is detected by the movable sensor 15 is obtained and stored (S53).
After this detection, the movable sensor 15 is moved by a predetermined distance in the paper feeding direction and the printing direction so that the movable sensor 15 is located at a position slightly inside the right end of the paper. It is stored on the RAM 41 (S54). And
Paper feed motor 12 when paper is detected by movable sensor 15
Is obtained (S55).

Next, the skew is obtained by subtracting the left end rotation angle and the moving amount in the sheet feeding direction from the right end rotation angle (S5).
6). In the case of the example of FIG. 14, if a table or the like prepared in advance is searched using the difference between the rotation angles obtained in S44 or S56, the closest value is obtained, and the type of paper corresponding to this is obtained from the table. Good.

The alignment for printing continuous form paper in the continuous tension mode is performed by a continuous tension registration unit (hereinafter, positioning unit) 5. The alignment processing unit 5 includes a CP
This is realized by U42 and an alignment processing program on the program ROM 40. Hereinafter, FIGS. 17 to 19
The processing performed by the alignment processing unit 5 will now be described.

The registration processing unit 5 automatically performs the printing registration of the continuous form paper. For this purpose, the position of the continuous form paper that has been once aligned with a predetermined position (the first line of printing) by the operator is stored in the nonvolatile memory 16. This predetermined position is determined by the paper sensor 34 provided on the continuous tractor 30.
Is obtained and stored with reference to the detection output of. Further, automatic positioning is also performed based on the detection output of the paper sensor 34.

The console 18 is used for this alignment, and various instructions are input to the processing device 1.
For example, a paper set switch (S
W), alignment SW, line feed SW, paper feed SW, and alignment SW. By depressing each SW, a predetermined instruction is input to the processing device 1.

FIG. 17 shows a procedure performed by the operator for this alignment. Paper set SW of console 18
When the button is pressed (S61), the passage is opened and the continuous paper can be inserted. Then, insert the continuous form paper into the inserter roller 2
The sheet is fed to the continuous tractor 30 from the side 4 under the print head 7 (S62), and the sheet feed and line feed are performed using the line feed SW and sheet feed SW of the console 18, and the sheet is adjusted to a predetermined position, that is, the first line of print. (S63).

Next, the paper setting switch and the positioning switch of the console 18 are simultaneously depressed (S64). In response, the alignment processing unit 5 stores the current position, that is, the position of the first print line, in the nonvolatile memory 16 by the processing shown in FIG.

With the above, the printing position alignment (S63) and the storage (S64) for the first continuous paper are completed. Thereafter, the printer is brought online with the main unit 17 to be in a print waiting state (S65).

The printing position of the second continuous paper is set in S6.
1, the paper set SW is pressed down (S66), S62
In the same manner as described above, the continuous paper is applied to the continuous tractor 30 (S6).
7) Then, only the alignment switch is pushed down (S68).

In response, the alignment processing unit 5 aligns the position of the continuous form paper with the position of the first line of printing stored in the nonvolatile memory 16 by the processing of FIG. FIG. 18 and FIG. 19 show the flow of the tension continuous sheet alignment processing performed by the alignment processing unit 5. In particular, FIG. 18 shows a storage process for a predetermined position (first line of printing) set by the operator in S64, and FIG. 19 shows an automatic print alignment process performed in S68.

In FIG. 18, when the sheet set SW and the positioning switch are simultaneously depressed, the positioning processing unit 5 is activated, and the storage operation is started. The continuous paper sheet aligned to the correct printing position by the operator is moved in the direction A in FIG. 2 by driving the continuous paper tractor 30 (S71), and the paper sensor 34 is turned on (the paper is present).
Is turned off (the state where there is no paper) from the printer (S7).
2).

If it is turned off, the value of the moving distance from the start of driving of the serial tractor 30 to the time of turning off is obtained (S73). This distance is obtained as the number of pulses (the number of steps of the change of the excitation phase) applied to the LF motor 10 that drives the continuous tractor 30. That is, the alignment processing unit 5 starts the timer 43 for starting the driving of the continuous tractor 30 in S71, and obtains the value of the timer at the time of turning off. Thus, it is possible to know how many pulses the position of the first print line set by the operator in the B direction from the position of the paper sensor 34.
The alignment processing unit 5 stores the number of pulses in the nonvolatile memory 16.
(S73).

Next, for printing on the continuous sheet (first sheet), the sheet is returned to the original position set by the operator (S74), and the process is terminated. For this reason, the continuous tractor 30 has the number of pulses stored in the nonvolatile memory 16.
Is driven in the B direction.

If the paper sensor 34 is not turned off in S72, it is checked whether the time is over (S75). If the time is not over, S71 and subsequent steps are repeated, and if the time is over, S74 is executed. For this reason, the value of the timer 43 at the time when the time is over is referred to and used to return to the original position.

As described above, the correct printing position set by the operator is automatically determined based on the position of the paper sensor 34 and stored. Therefore, it can be said that there is no increase in the burden on the operator. On the other hand, printing on the first continuous paper can be performed correctly.

In FIG. 19, when only the positioning switch is depressed, the positioning processing unit 5 is started, and the positioning (setting) operation is started. The continuous form paper appropriately applied to the continuous form tractor 30 by the operator is moved in the direction A of FIG. 2 by driving the continuous form tractor 30 (S81), and it is checked whether the paper sensor 34 has been turned off from on. (S82).

When the vehicle is turned off, the continuous tractor 30
Is stopped, and then the continuous tractor 30 is driven in the B direction by the number of pulses stored in the nonvolatile memory 16 (S
83) End the process. Thereby, the continuous form paper is conveyed so as to be aligned with the position of the correct first print line based on the position of the paper sensor 34.

If the paper sensor 34 is not turned off in S82, it is checked whether the time is over (S84). If the time is not over, the process from S81 is repeated. If the time is over, the value of the timer 43 at the time when the time is over is referred to. Driven (S8
5).

As described above, in the correct printing position set by the operator for the first time, the paper sensor 34 is set for the second and subsequent times.
Are automatically aligned based on the position of. Therefore,
There is no operator burden.

After S85, the position of the continuous form paper to be applied to the continuous form tractor 30 may be slightly shifted in the direction A to retry. In this embodiment, the alignment switch is used, but only the paper set switch provided in any printer may be used without providing the alignment switch. For example, when the paper set SW is pressed down, the original operation of opening the passage is performed when the paper sensor 34 is off, and the function instead of the alignment SW is performed when the paper sensor 34 is on (starts the alignment operation). You may do so.

A plurality of values may be stored and designated in the nonvolatile memory 16 for use. Thereby, it is possible to cope with a plurality of different continuous papers (different first print lines).

[0144]

As described above, according to the present invention,
By providing the printer with an automatic skew check function, the skew check time can be significantly reduced, the throughput can be improved, and the burden of the operator on the skew check can be almost eliminated.

[Brief description of the drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a schematic configuration diagram of a printer.

FIG. 3 is a schematic configuration diagram of a printer.

FIG. 4 is a diagram showing the effect of the present invention.

FIG. 5 is a diagram showing the effect of the present invention.

FIG. 6 is an explanatory diagram of an embodiment.

FIG. 7 is an explanatory diagram of an embodiment.

FIG. 8 is a printing amount control processing flow.

FIG. 9 is an explanatory diagram of an embodiment.

FIG. 10 is an explanatory diagram of an embodiment.

FIG. 11 is a flowchart of ruled line interpolation processing.

FIG. 12 is an explanatory view of the embodiment.

FIG. 13 is an explanatory view of another embodiment.

FIG. 14 is an explanatory view of another embodiment.

FIG. 15 is a skew detection processing flow.

FIG. 16 is a skew detection processing flow.

FIG. 17 is a diagram showing a procedure for aligning a tension continuous form.

FIG. 18 is a flow chart of a registration process of a tension continuous form.

FIG. 19 is a flow chart of a registration process of a tension continuous form.

FIG. 20 is an explanatory diagram of a conventional technology.

FIG. 21 is an explanatory diagram of a conventional technique.

FIG. 22 is an explanatory diagram of a conventional technique.

FIG. 23 is an explanatory diagram of a conventional technique.

FIG. 24 is an explanatory view of a conventional technique.

FIG. 25 is an explanatory view of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing unit (CPU / memory) 2 Print amount processing unit 3 Ruled line interpolation processing unit 4 Skew processing unit 5 Tensile continuous registration processing unit 6 Thermal sensor 7 Print head 8 CR motor 9 Print control unit 10 LF motor 11 Line feed control Unit 12 Paper feed motor 13 Paper feed control unit 14 Fixed sensor 15 Movable sensor 16 Non-volatile memory 17 Main unit 18 Console

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yasunori Taniguchi 98-2 Unoki-nu, Unoki-cho, Kawakita-gun, Ishikawa Pref. (72) Inventor Hitoshi Asai Unoki-nu, Unoki-cho, Kawakita-gun, Ishikawa 98-2 Inside PFU Co., Ltd. (72) Inventor Shunpei Teranishi 98-2 Unoki Nu, Unoki-cho, Kawakita-gun, Ishikawa Prefecture (56) Reference JP-A-63-17750 (JP, A) Kaihei 3-253868 (JP, A) JP-A 61-193944 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65H 7/08 B41J 11/42

Claims (1)

(57) [Claims] The rotation is performed by sequentially changing the excitation phase of a magnetic pole.
A printer that automatically obtains a skew for a sheet fed by the motor using a motor that is driven by the motor , wherein the sensor detects a position of the sheet, and is at least movable in a width direction of the sheet. One movable sensor (15) and a skew processing unit (4) for obtaining the skew are provided, and the skew processing unit (4) includes the movable sensor (15).
Was detected the sheet in the width direction of the one end of the sheet is moved in a predetermined direction, the rotation angle before liver over data of the detection time determined by detecting the detection time of the excitation phase, the width of the paper calculated rotation angle before liver over data upon detecting the sheet in the direction of the other end detects the excitation phase of the detection time, the 2
A printer that calculates the skew from a difference between two rotation angles.