JP2002192787A - Serial printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize high speed printing by making the constant print speed variable line by line depending on the print rage. SOLUTION: Print rage is determined line by line and when the print start position Ps and the print end position Pe satisfy following relations P1<=Ps<P2 and P5<Pe<=P6, printing is performed at a low speed because the slow up distance and slow down distance are short. Since the slow up distance and slow down distance are lengthened to some extent when P2<=Ps<P3 and P4<Pe<=P5 are satisfied, printing is performed at an intermediate speed and since the slow up distance and slow down distance are sufficiently long when P3<=Ps and Pe<=P4 are satisfied, printing is performed at a high constant speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a serial printer for performing printing while moving a carrier on which a head is mounted.

[0002]

2. Description of the Related Art In a serial printer, a carrier on which a head is mounted starts moving along a platen from a stop position by slow-up control. Control to stop by slowdown control is performed. The speed at the constant speed for printing is determined by the position at which the carrier is stopped, the distance for slowing up to the start end of the print area, and the distance for slowing down from the end of the print area to the position at which the carrier is stopped. .

[0003]

However, the printing range may be different for each line. For example, the printing range of a certain line may be biased toward the center of the printing area.In such a case, the distance from the stop position of the carrier to the position where printing is actually started becomes longer. Conventionally, printing is performed only at a determined constant speed, and thus printing cannot be performed at high speed.

Accordingly, the present invention provides a serial printer capable of changing the speed at the time of constant speed printing for each line in accordance with the printing range, thereby increasing the printing speed.

[0005]

According to the first aspect of the present invention,
After slowing up the carrier with the head mounted, it prints one line at a constant speed. When the printing of one line is completed, it slows down and stops, and in a serial printer that repeats this operation line by line, it prints line by line A position detecting means for checking the area to detect the start position and the end position of the printing, and the higher the distance that can be used for slow-up and slow-down by the start position and the end position of the printing detected by the position detecting device, the higher the speed. A mode switching means for switching the speed of the carrier at a constant speed to a plurality of stages so as to perform printing at a speed.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a control unit of a serial printer.
Is a RO that stores program data for controlling each part and character information for developing print data into a dot pattern.
M (read only memory) 3, RAM for storing received print data, memory for data processing, RAM (random access memory) provided with memory for storing data expanded into dot patterns, Operation panel 5 with keyboard and display,
A host interface (I / F) 6 for receiving print data from a host computer such as a personal computer, which is a higher-level device for transmitting print data, and a printer controller 7 are connected.

The printer controller 7 has a head driver 9 for driving a print head 8 mounted on a carrier, a motor driver 11 for driving a carrier motor 10 for moving the carrier along a platen, and a coil wound around the platen. A motor driver 13 that drives a line feed motor 12 that feeds the printing paper line by line is connected.

The printer controller 7 includes:
A motor driver 15 for driving an automatic gap motor 14 for automatically adjusting the gap between the print head 8 and the platen, and a sensor 16 for detecting a jam of the print paper or the like are connected. An encoder 17 is attached to the carrier motor 10, and the encoder 17 detects forward rotation and reverse rotation of the carrier motor 10,
The rotation information is notified to the CPU 2 via the printer controller 7.

FIG. 2 is a flowchart showing speed control of the carrier motor 10 by the CPU 2 during a printing operation. First, in step S1, the carrier motor 10 is controlled.
To set the print head 8 at the home position P0. At this time, the carrier 20 is also located at the home position P0 as shown in FIG.

Before starting printing of one line,
In step S2, it is determined whether or not the number of print digits of the line is 136 digits for printing from one end P1 to the other end P6 of the print area. If the number of printing digits is 136, the speed mode of the carrier motor 10 is changed to the first speed mode in step S3.
Mode is switched to the low speed mode.

Subsequently, in step S4, the carrier motor 10 is slowed up. Then, step S5
It is determined from the information from the encoder 17 that the carrier 20 has reached the start end position P1 of the print area and has reached the low constant speed, which is the first speed at which printing is performed. When it is determined that the start position Ps has been reached, in step S7 the carrier 20 is driven at a low constant speed.
Is performed to the printing end position Pe while controlling the movement of. In this case, the print start position Ps and the print end position Pe
Are Ps = P1 and Pe = P6, respectively.

Then, in step S8, the carrier 20
Has reached the end position P6 of the print area,
In step S9, the carrier motor 10 is slowed down. In step S10, when it is determined that the carrier 20 has reached the stop position P7, the carrier motor 10 is stopped.

If it is determined in step S2 that the number of print digits of the line is less than 136,
At 11, the print range, that is, the print start position Ps and print end position Pe of the line are confirmed. (Position Detecting Means) Then, in step S12, it is determined whether high-speed printing is possible. That is, it is determined whether the print start position Ps of the line is P3 ≦ Ps and the print end position Pe is Pe ≦ P4.

If P3.gtoreq.Ps or Pe.ltoreq.P4, that is, if high-speed printing is not possible, it is determined in step S13 whether medium-speed printing is possible. This is because the print start position Ps of the line is P2 ≦ Ps and the print end position Pe
Is determined to be Pe ≦ P5.

If P2 ≧ Ps or Pe ≦ P5, that is, if high-speed printing is not possible, at step S3,
The speed mode of the carrier motor 10 is switched to the low speed mode. (Mode switching means)
4 to S10 are performed, and printing is performed at a low constant speed. In this case, the print start position Ps and the print end position Pe
Are P1 <Ps <P2 or P5 <Pe <P6.

In step S13, if the print start position Ps of the line is P2≤Ps and the print end position Pe is Pe≤P5, it is determined that medium speed printing is possible, and in step S14. Then, the speed mode of the carrier motor 10 is switched to the medium speed mode, which is the second mode.
(Mode Switching Means) Subsequently, in step S15, the carrier motor 10 is slowed up.

Then, in step S16, carrier 2
It is determined that 0 has reached the intermediate fixed speed which is the second speed at which printing is performed.
When it is determined from the information from 7 that the carrier 20 has reached the print start position Ps, printing is performed up to the print end position Pe while controlling the movement of the carrier 20 at a medium constant speed in step S18.

Then, in step S19, carrier 2
When it is determined that 0 has reached the print end position Pe, in step S20, the carrier motor 10 is slowed down, and in step S21, the carrier 20 is stopped.
When it is determined that the number has reached 7, the carrier motor 10 is stopped.

In step S12, if the print start position Ps of the line is P3 ≦ Ps and the print end position Pe is Pe ≦ P4, it is determined that high-speed printing is possible, and in step S22, The speed mode of the carrier motor 10 is switched to the third mode, that is, the high speed mode.
(Mode Switching Means) Subsequently, in step S23, the carrier motor 10 is slowed up.

Then, in step S24, carrier 2
It is determined that 0 has reached the high constant speed which is the third speed at which printing is performed.
When it is determined from the information from 7 that the carrier 20 has reached the print start position Ps, printing is performed up to the print end position Pe while controlling the movement of the carrier 20 at a high constant speed in step S26.

Then, in step S27, carrier 2
When it is determined that 0 has reached the print end position Pe, the carrier motor 10 is slowed down in step S28, and the carrier 20 is stopped in step S29.
When it is determined that the number has reached 7, the carrier motor 10 is stopped.

In such a configuration, the carrier 20
When printing is performed by controlling the movement of the print start position Ps and the print end position Pe for each line, the print start position Ps is checked.
s and the print end position Pe are P1 ≦ Ps <P2, P5, respectively.
If <Pe ≦ P6, the slow-up distance and the slow-down distance are short. At this time, printing is performed at a low constant speed. If ≤P5, the slow-up distance and the slow-down distance become longer to some extent. At this time, printing is performed at a medium constant speed, and the print start position Ps and the print end position Pe are respectively P3≤P
If s, Pe ≦ P4, the slow-up distance and the slow-down distance are sufficiently long, and at this time, printing is performed at a high constant speed. As is apparent from FIG. 3, the third speed is equal to the second speed.
The second speed is controlled at a higher speed than the first speed, and the second speed is controlled at a higher speed than the first speed.

As described above, since the moving speed of the carrier 20 at the time of printing is varied depending on the printing range, when the printing range is biased toward the center of the printing paper, printing is performed at a high constant speed or a medium constant speed. As a result, the printing speed can be increased as a whole. In this respect, in the related art, since the constant speed is determined by the printing area, printing is always performed at a low constant speed even if the printing range is biased toward the center of the printing paper.

The control of the moving speed of the carrier 20 can be applied to both forward printing and reverse printing. Therefore, in the case of reciprocating printing, such control is performed on both the forward path and the return path.

Generally, the moving speed of the carrier 20 is as follows:
It changes according to the printing type such as first draft, draft, near letter quality, letter quality, etc.If the present invention is applied, the printing speed can be varied for each line in each printing type. become.

In this embodiment, the constant speed of the carrier at the time of printing is changed to three steps of low speed, medium speed and high speed. However, the present invention is not limited to this.
It may be variable in two stages, or may be variable in four or more stages.

[0027]

As described in detail above, according to the present invention,
The speed at the constant speed for printing line by line according to the printing range can be changed so that the printing speed is higher when the printing range is biased toward the center of the printing area, thereby increasing the printing speed. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of the present invention.

FIG. 2 is a flowchart showing speed control of a carrier motor in the embodiment.

FIG. 3 is a diagram for explaining a relationship between a printing range and a speed when the carrier moves at a constant speed in the embodiment.

[Explanation of symbols]

 2 CPU (Central Processing Unit) 3 ROM (Read Only Memory) 8 Print Head 10 Carrier Motor 20 Carrier

Claims (1)

[Claims] 1. A serial printer which prints one line at a constant speed after a carrier with a head mounted thereon is thrown up, and slows down and stops when one line printing is completed, and repeats this operation line by line. A position detecting means for checking a print area for each line to detect a print start position and an end position, and a distance that can be used for slow-up and slow-down depending on a print start position and an end position detected by the position detect means. A serial printer, comprising: mode switching means for switching the speed of the carrier at a constant speed to a plurality of stages so that printing is performed at a higher constant speed as the length becomes longer.