JP2731460B2 - Left and right edge position detection method for printer paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a left-right end position detecting method of printer paper, in particular, to a method for detecting the left-right end position of the print sheet in minimum time.

[0002]

2. Description of the Related Art There is a serial printer capable of printing on various sheets such as cut sheets, continuous form sheets, and cut sheet sheets.
In such a serial printer, paper of an arbitrary size can be set at an arbitrary position. Therefore, the left end and right end positions are detected to prevent breakage of the print head by preventing empty printing where there is no paper. ing. That is, a sensor for detecting the left end and right end of the printer paper is provided on the print head carrier of the serial printer, the left end and right end positions are detected by the sensor for each line, and printing is performed only in a range where the paper exists. I have.

[0003]

When a cut sheet feeder or a continuous form is used, the position of the sheet does not change once it is set. For this reason, when using the cut sheet feeder or continuous form, the leftmost
There is no need to detect the right end position. However, in the conventional method, since the left end / right end position is detected for each row, the left end / right end position detection is a wasteful operation, and the entire system is not used.
There was a problem that led to a decrease in put.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for detecting the left and right edge positions of printer paper which can minimize the left and right edge position detection operations of the paper and improve the system throughput.

[0005]

FIG. 1 is a diagram illustrating the principle of the present invention. Reference numeral 11 denotes a printer control unit for controlling the entire printer, 12 denotes left and right end position detecting means for detecting the left and right end positions of the sheets set in the printer, and 13 denotes a set sheet type for specifying the type of the sheet to be set in the printer. Designating means (operation unit) 14 includes various sensor units for detecting whether or not a sheet is set in a printer, whether or not a cut sheet is sucked into a platen, and the like.

[0006]

The printer controller 11 determines whether a sheet to be set in the printer is a cut sheet or a continuous form based on the designation of the set sheet type designation means 13 (1).
When printing on a cut sheet, 1
When the first (first) cut sheet is sucked into the platen from the hopper, the left and right end position detecting means 12 of the sheet is instructed to detect the left and right end positions of the sheet. After detecting that there is no paper, when the paper is set, an instruction to detect the left end and right end positions is given. Paper left edge
When the right end position detecting means 12 receives the detection instruction, the print head mounted carrier is moved from the initial position in the printing line direction, and based on the carrier movement amount when the left end and the right end of the paper set in the printer are detected, the right end of the paper is detected. The left end position and the right end position are detected.

As described above, when the cut sheet is used, the sheet is set when the first cut sheet is sucked into the platen from the hopper. Since it is only necessary to detect the left and right end positions of the sheet when the operation is performed, the left and right end position detecting operations can be minimized, and the throughput of the system can be improved.

When the power is turned on, it is checked whether continuous form paper is set.
If the right end position is detected, even if the continuous form paper is continuously set regardless of the power on / off, only one detection operation after the power is turned on may be performed. The left and right end position detection operations can be minimized, and the throughput of the system can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Overall Configuration FIG. 2 is a configuration diagram of a main part of a serial printer according to the present invention. In the figure, reference numeral 11 denotes a printer control unit that controls the entire apparatus, and includes a processor (CPU) 11a, a program memory (ROM) 11b, a data memory (RAM) 11c, and the like. Reference numeral 12 denotes a sheet left and right end position detecting unit for detecting the left and right ends of the sheet set in the printer.
Reference numeral 3 denotes an operation unit for designating the type of paper to be set in the printer. The type of paper (cut sheet, continuous form paper,
It has a lever 13a for designating (cut sheet) and a paper set button 13b pressed when the paper is set in the printer. Numeral 14 denotes various sensor units for detecting whether or not the sheet is set in the printer, whether or not the cut sheet is sucked into the platen, whether or not the carrier exists at the initial position, and the like. . 15 is a platen, 16
Is paper set in the printer.

Paper Left Edge / Right Edge Position Detecting Unit In the paper left edge / right edge position detecting unit 12, reference numeral 12a denotes a stepping motor (space motor) for moving a carrier.
12b, a stepping motor control circuit for controlling the stepping motor, and 12c, counting the number of stepping motor driving pulses, monitoring the current position Pa from the leftmost position (initial position) of the carrier, and forming a sheet 16. position monitoring unit for storing seeking the left end position P _L and the right end position P _R, 12
d is a carrier which moves left and right by rotation of the stepping motor, 12e is a print head mounted on the carrier, 1
2f and 12g are attached to the left and right sides of the carrier, respectively.
These are first and second sensors for optically detecting the left end and the right end of the sheet.

The detection of the left end of the sheet by the first sensor 12f is such that when the background changes from black to white (sheet), the light output from the light emitting element of the first sensor is reflected on the sheet and enters the light receiving element. This can be performed by detecting this reflected light. Also, the second
The detection of the right end of the sheet by the sensor can be performed by detecting the light output from the light emitting element of the second sensor when the background changes from white (paper) to black, and does not enter the light receiving element.

[0012] set state diagram 3 of the sheet is paper set state illustration, in FIG. 2 the same parts are denoted by the same reference numerals. 16a is a continuous form paper (referred to as continuous form paper), 16b is a cut sheet, 21 and 22 are paper feed rollers, and 23 is a rule to which the carrier 12d is connected.
It is a belt-shaped belt. The belt 23 is driven by the stepping motor 12a to move the carrier in the direction of the arrow. 24 is a sheet feeder, and 25 is a pickup roller for feeding out a cut sheet. FIG. 3 shows a state in which the continuous form paper is set in the printer. When printing on a cut sheet, the continuous form paper is removed, and the cut sheet is fed from the sheet feeder 24 by the pickup roller 25 to the cut sheet.
Is fed out onto the platen.

Detection of Left and Right Edges of Paper The left and right edges of the paper are detected as follows. That is, the stepping motor 12a is rotated to position the carrier 12d at the initial position. Thereafter, the carrier is moved rightward from the initial position and the current position Pa of the carrier 12d is monitored by counting the stepping motor drive pulses. Then, the current position paper left end position P _L when the first sensor 12f detects the left edge of the paper
Is stored in the position monitoring unit 12c as the second sensor 1
2g detects a left-right end position of the paper by storing the current position when it detects the right edge of the paper position monitoring unit 12c as the sheet right end position P _R.

Detection Control of Left and Right Edge Positions of Paper Hereinafter, the control of detecting the left and right edge positions of the paper according to the present invention will be described with reference to the flowcharts of FIGS.

(A) When power is turned on (see FIG. 4) When the power of the printer is turned on, the printer controller 1
The first processor 11a is subjected to a power-on reset (initial reset). Thereafter, the ROM check and the RAM check are performed by a diagnostic program, and the printer mechanical control unit is initialized (steps 101 to 103).

Next, the processor 11a checks whether a continuous form is selected by the lever 13a of the operation unit 13 (step 104). If the lever is not at the continuous position, the left and right end positions of the sheet when the power is turned on are detected. The control ends.

However, if the continuous paper is selected by the lever, it is determined whether or not the paper (continuous paper) is set in the printer by a signal from the sensor unit 14 (step 105). If not, the control for detecting the left and right edges of the sheet when the power is turned on ends.

If a sheet is set, the sheet is a continuous sheet, and the sheet width detection routine is executed to detect the left and right edge positions of the sheet (step 106). The right end position detection control ends.

(B) Paper width detection routine In the paper width detection routine, as shown in FIG. 5, the processing unit 11a first determines whether the current position of the carrier 12d is at the leftmost position (initial position). The signal is checked by the signal from the unit 14 (step 201). If the carrier is not at the initial position, the stepping motor 12a is rotated counterclockwise to return the carrier 12d to the initial position (step 202,
203) After that, the rotation of the stepping motor is stopped (step 204), and the process returns to step 201 to repeat the subsequent processing.

In step 201, if the carrier is at the initial position, the carrier current position Pa is cleared to 0, the stepping motor 12a is rotated to move the carrier to the right, and the stepping motor driving pulse is output. It counts and holds the current position Pa of the carrier 12d (step 205).

The movement of the carrier causes the first sensor 12
It is monitored whether or not f has detected the left end of the sheet (step 20).
6), by detecting the sheet left, and stores the position monitoring unit 12c the current position at that time as the sheet left end position P _L (step 207).

Thereafter, it is monitored whether the carrier moves further and the second sensor 12g detects the right end of the sheet (step 2).
08), by detecting the paper right edge, stores the present position at that time position monitoring unit 12c as the sheet right end position P _R (step 209), stepping - stops data (step 210). Thus, it is possible to detect the left end position P _L and the right end position P _R of the paper.

(C) When setting paper (see FIG. 6) When setting predetermined paper in the printer, the operation
The printer determines the type of paper to be set (step 30).
1) In the case of a cut sheet, since the left and right end positions of the sheet are detected when a print command, which will be described later, is issued, the left and right end position detection control during sheet setting is not performed.

If the paper to be set is a continuous form, it is checked by the lever 13a whether the continuous form is selected (step 302). If the continuous form is selected by the lever 13a, the paper (continuous form) is selected. (Step 303), and if continuous form paper is set,
When the continuous paper is set, the left and right end position detection operations have already been completed, so the left and right end position detection control of the paper is ended.

On the other hand, if the lever is not at the continuous position in step 302, and if paper (continuous paper) is not set in step 303, the operator
The user performs a continuous book setting operation of setting the continuous book on the printer (step 304). In addition, when setting the continuous paper, the lever 13a is set to the continuous position and the paper setting button 13 is set.
b.

When the continuous book setting operation is completed, the processing unit 11a of the printer control unit 11 presses the paper set button 13b,
The paper width detection routine (FIG. 5) is executed by detecting that the paper has been set from the state of no paper, and the left end position and the right end position of the continuous book are detected (step 305). The detection control ends.

In step 301, if the sheet to be set is a cut sheet, the continuous form is
Alternatively, it is checked whether or not a cut sheet is selected (step 30).
6) If a continuous form is selected by the lever 13a, it is checked whether paper is set in the printer (step 307). If continuous paper is set, the continuous paper is retracted (step 307). Step 308).

[0028] After the sheet reverse control completes, or cut sheet is not selected by the lever -13a at step 306
When the cut sheet is not set or the cut sheet is not set, the operator performs a cut sheet setting operation for setting the cut sheet to the printer (step 309). The setting of the cut sheet is performed by setting the lever 13a to the cut position and pressing the sheet set button 13b.

When the cut-sheet setting operation is completed, the processing section 11a of the printer control section 11 detects that the sheet has been set from the state of no sheet after pressing the sheet set button, and detects the sheet width by the sheet width detection routine (FIG. 9). 5) is executed to detect the left end position and the right end position of the cut sheet (step 305),
The right end position detection control ends.

(D) At the time of a print command (FIG. 7) When a print command is received from a host or the like, the printer controller 1
In the first processing unit 11a, the lever 13a has a cut sheet (sheet).
Is determined (step 40).
1) If a sheet other than the cut sheet (continuous form, cut sheet) is selected, it is not necessary to perform the operation of detecting the left end and right end positions of the sheet at the time of the print command, so that the print control is performed thereafter.

If the cut sheet has been selected, it is determined whether the sheet has been sucked into the platen (step 40).
2) If the paper has been inhaled, the print control is performed because the left and right edges of the paper have already been detected.

If the cut sheet has not yet been sucked into the platen, the cut sheet is sucked from the hopper by the sheet feeder, and it is checked whether the paper width detection flag is "1" (steps 403 to 404). ).

If the paper width detection flag is "0", the paper width detection routine is executed to detect the left and right edge positions of the paper (step 405). Thereafter, the paper width detection flag is set to "1". (Step 406), and printing is performed.

Thereafter, every time there is a print command, the above step 4 is performed.
The processing after 01 is performed, but the paper width is not detected because the flag is “1”. That is, the cut sheet
In the case of using the tofeeder, detection control of the left and right end positions of the sheet is performed only when the first cut sheet is sucked into the platen. This is usually the case when printing two or more sheets.
After the first sheet, the sheet size is the same as that of the first sheet.

The flag is reset to "0" when the paper width adjusting mechanism of the hopper operates.

The present invention has been described with reference to the embodiments.
The present invention can be variously modified in accordance with the gist of the present invention described in the claims, and the present invention does not exclude these.

[0037]

As described above, according to the present invention, when a cut sheet feeder (cut sheet) is used, the left and right end positions are detected when the first cut sheet is sucked into the platen. When using continuous form paper, the system detects the absence of paper and then detects the left and right edge positions when paper is set. Can be improved, and the breakage of the head pin can be prevented by detecting the paper width.

Further, according to the present invention, when the power is turned on, it is checked whether or not the continuous form paper is set, and if it is set, the left and right end positions thereof are detected. Even if they are set continuously regardless of ON / OFF, it is only necessary to perform the detection operation once after the power is turned on. Put can be improved.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a sheet setting state.

FIG. 4 is a flowchart of sheet left and right end position detection control when power is turned on.

FIG. 5 is a flowchart of a sheet width detection routine.

FIG. 6 is a flowchart of left end / right end position detection control at the time of sheet setting.

FIG. 7 is a flowchart of sheet left end / right end position detection control at the time of a print command.

[Explanation of symbols]

 11. Printer control unit 12. Paper left end / right end position detection means 13. Set paper type designation means 14. Various sensor units

Claims (2)

(57) [Claims] 1. A sensor for detecting the left and right edges of printer paper is provided on a print head carrier of a serial printer, and the carrier is moved from an initial position in a printing line direction to detect the left and right edges of the printer paper by the sensors. In the left and right end position detection method of printer paper for detecting the left end and right end positions of the printer paper based on the movement amount of the carrier, the cut sheet is specified based on the designation of the set paper type designation means.
If the cut sheet is used as the printer paper , the left and right end positions are detected when the first cut sheet is sucked into the platen, and the continuous form paper is used. In the case of use, a left and right end position detection method for printer paper, wherein the left and right ends of the paper are detected when paper is set after detecting the absence of paper. 2. The printer according to claim 1, wherein when the power is turned on, it is checked whether continuous form paper is set, and if it is set, the left and right end positions of the continuous form paper are detected. How to detect the left and right edges of paper
Law .