JPH0422668A - Printer fitted with paper width detector - Google Patents

Abstract

PURPOSE:To certainly carry out the printing within paper by measuring the degree of inclination of the paper taken in a paper width detector at the point of time when the paper is taken in a printer and determining a printing start position and a printing completing position thereafter on the basis of the degree of inclination. CONSTITUTION:The degree of inclination of paper is calculated according to formula (LT-L1)/T to be stored as dL and the moving quantity from a top margin position is stored as V and the printable left margin position at this position is calculated according to formula LT+dLXV+M to be stored as LV. A printable right margin position is calculated according to formula RT+ dLXV-M to be stored as RV. Herein, M is a margin value. The printable left margin LV is compared with a printing data left margin LD to judge whether LV is larger than LD and, at the time of LV>LD, LV is stored as a printing executing left margin LP and, at the time of LV<LD, a step 104 is taken and LD is stored as OP. In the same way, RV is stored as a printing executing right margin RP and printing is executed within the range of the printing executing left margin LP and the printing executing right margin RP.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing apparatus system using a wire tod head or an inkjet head.

[Prior Art] Most printer systems using conventional wire head or inkjet heads do not have a means for detecting the width of paper to be printed.
Therefore, if print data that exceeds the paper width is sent from the host convenience store, it will be printed outside the paper. Problems such as wires breaking have occurred. Further, in printers using inkjet heads, problems occur in that ink adheres to the platen and stains the next sheet of paper.

In order to solve this problem, an increasing number of printers have recently been equipped with a paper width detector on the carriage to measure the width of the paper before printing, thereby ensuring that printing can be performed within the paper.

[Problems to be Solved by the Invention] However, in a printer equipped with a paper width detector as described above, the print-prohibited area within the paper is made large in consideration of oblique insertion of the paper. As a result, problems such as print data not being able to fit onto the paper have started to occur.

On the other hand, if print data is to be loaded all over the paper, it is necessary to measure the width of the paper immediately before electrostatic printing, and such a method results in a decrease in printing speed.

[Means for Solving the Problems] The present invention was invented in order to solve the above-mentioned problems, and calculates the degree of inclination of the printing paper when it is taken into the printer, and calculates the degree of inclination based on this degree of inclination. By calculating the printable left and right edge positions in advance before starting printing of the boat, it is possible to ensure that printing is performed on the paper and also on the paper and on the cup. .

Furthermore, by measuring the paper width only when the paper is taken in, the reduction in printing speed is attempted to be minimized.

[Implementation example 1] The present invention will be explained in detail based on examples.

FIG. 1 is a perspective view of a printer system according to an embodiment of the present invention. A carriage 1 is equipped with a print head 2 and a paper width detection device 3, and is moved in the direction of the arrow by driving a carriage motor 4 via a belt 5. 6
is a platen, which feeds the printing paper 8 by driving the line feed motor 7.

The paper width detection device 3 is a reflective optical sensor, and has the highest reflectance on the paper and the lowest reflectance on the black platen, so it can easily detect the boundary between the paper and the platen. 9 is a print head 2 and a paper width detection device 3;
, carriage motor 4, line feed motor 7, and the like.

FIG. 2 is a block diagram of a control system of a printer according to an embodiment of the present invention. 10 is a central processing unit (CPU), and DAT
A ROM in which control programs and character fonts are stored is connected via the A signal line 11 and the ADDRESS signal IJi 12.
13. RAM 14 which is read and written as a print buffer and data receive buffer. A print control section 15 and a data reception section 16 are connected, and a host computer 17
The printer receives data from the printer and executes the print operation.

The print control section 15 controls each operating means during printing, and in the illustrated example, controls the print head 2 via a head driver 18 and the line feed motor 7 via an LFM (line feed motor) driver 20. (
The carriage motor 4 is configured to be controlled via a carriage motor driver 21. Further, an input signal from the paper width detection device 3 is input to the print control section 15 via the receiver 22.

FIG. 3 is a flowchart showing a control operation procedure according to an embodiment of the present invention. First, in step 100, the printing paper is sent and the top edge of the paper is set at the position where the paper width detector is stably turned on.Next, the process proceeds to step 101, where the carriage 1 is moved left and right to detect the paper width. Measure the left and right edges of the paper using device 3, and store the left edge as L and the right edge as R1.6 Next, in step 102, feed the paper to the top margin position, and set the amount of movement from the top edge of the paper to T.
Remember it as. The area from the margin position to the top of the paper is an area in which printing is impossible, and various values are taken depending on the control system of the printer. 103 at this position
Moving on to the step, the left and right edges of the paper are measured again, and the left edge is memorized as LT and the right edge is memorized as RT. The process then moves to step 104, where the degree of inclination of the paper is calculated using the formula (LT-Ll)/T and stored as dL. Next, the process proceeds to step 105, where the received data written in the receive buffer in the RAM 14 from the host computer is taken out one after another, and in the case of character data, character fonts are developed and written in the print buffer.

Next, in step 106, it is determined whether the data of one line taken out is line movement data. 1 for row movement data
The process advances to step 07 and the paper is fed by a predetermined amount.

After that, proceed to step 108 and store the amount of movement from the top margin position as V. In step 109, the printable left edge position at this position is determined by LT + dLX.
Calculate using the formula V+M and store as LV. Also, calculate the printable right edge position using the formula RT + dLXV-M, and
be memorized as Here, M is a margin value that takes into account the accuracy of the paper width detection device and the mounting precision between the print head 2 and the paper width detection device 3. This completes the processing of the line movement data, and the process returns to step 105 to retrieve the next data.

It is determined in step 110 whether the one line of data extracted in step 106 is print data. If it is print data, the process advances to step 111, and from one line of print data, the left end of the print data is stored as LD and the right end as RD.

Next, the process advances to step 112, where the printable left end (LV) and print data left end (LD) are compared to determine whether LV is larger than LD. 11 if LV is greater than or equal to LD
Proceed to step 3 and store the LV as the print execution left end (LP). If LV is smaller than LD in step 112, the process advances to step 104 and LD is stored as LP.

Next, the process advances to step 115, where the printable right end (RV) and the print data right M (RD) are compared, and it is determined whether RV is smaller than RD. 11 if RV is less than or equal to RD
Proceed to step 6 and store RV as the print execution right end (RP). If RV is greater than RD in step 115, the process advances to step 117 and RD is stored as RP. Next, the process advances to step 118, and printing is executed within the range of the print execution left end (LP) and the print execution right end (RP). When printing is completed, the process returns to step 105 to process the next data.

FIG. 4 is a diagram illustrating the above explanation.As mentioned above, according to the present invention, areas that cannot be printed are as shown above.
The only issues are the accuracy of the paper width detector and the mounting accuracy of the print head and the paper width detector. For this reason, at worst, only about 1 mm on either side becomes an area where printing is impossible.

In contrast, in the conventional method, it is necessary to take into account the inclination caused by inserting the paper. Even if the paper feeding mechanism, paper guide, etc. are devised, the inclination caused by inserting the paper will still occur by about ±0.3°. Therefore, for A4 size, it is 297mm
tan0.3° = 1.6mm, and if you add paper width detector accuracy and paper width detector mounting accuracy to this, it is 4.2m on the left and right sides.
The area around m is unprintable. FIG. 5 shows the print area according to the present invention, and FIG. 6 shows the print area according to the conventional method, and it can be seen that the print area according to the present invention is wide.

r Effects of the Invention] As is clear from the above description, according to the present invention, printing can be performed reliably on printing paper, the printing area can be secured to the maximum, and there is no need to worry about missing data. Furthermore, the time required to detect the paper width is short, making it possible to minimize the decrease in printing speed, which has great effects.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a printer system according to an embodiment of the present invention;
FIG. 2 is a control system block diagram of an embodiment of the present invention, and FIG. 3 is a flowchart showing a control operation procedure of an embodiment of the present invention.
FIG. 4 is a diagram to supplement the flowchart of the present invention, FIG. 5 is a diagram showing a print area of the present invention, and FIG. 6 is a diagram showing a print area according to a conventional method. that's all

Claims (1)

[Claims] In a printer equipped with a moving carriage, a print head mounted on the carriage, and a paper width detection device,
When the paper is taken into the printer, the degree of inclination of the taken-in paper is measured by a paper width detection device, and the subsequent print start position and print end position are determined based on the measured degree of inclination. Printer system with paper width detection device.