JPS60236781A - Serial printer controlling system - Google Patents

Abstract

PURPOSE:To prevent runaway of a carriage from occurring when something collides against the carriage during printing and perform a treatment such as issuing of an alarm even when a printing position is stagerred by several pitches, by providing a position sensor and a position counter for the carriage. CONSTITUTION:A printing-controlling part 1 controls a printing head 3 through a printing driving part 2, and supplies a carriage-driving part 4 and the position controller 6 with information on moving direction and distance. The counter 6 counts up in response to rightward movement of the carriage 8 and counts down in response to leftward movement of the carriage 8, with a home position as a reference value, and sends a logical position of the carriage 8 to a sequential comparing part 7. The comparing part 7 compares the logical position with a current physical position of the carriage obtained by a sensor part 5 (16-18). If the physical position is out of a normal range, the position of the carriage 8 (13) is corrected or the carriage is stopped, through the carriage-driving part 4, and an alarm is issued.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a control method for a serial printer used as an output device of a computer, etc.

[Conventional technology and problems]

Conventionally, in serial printers that print one character at a time while moving a carriage carrying a print head along the print line, for example, if something physically touches the carriage during printing, the carriage may run out of control. There was a collision with the mechanical frame. For this reason, there has been a method in which sensors are attached to both ends of the mechanical frame so that when the carriage runs out of control and deviates from the printing range, the sensor detects this and generates an alarm or the like.

However, this method is only effective when the carriage goes out of control and deviates from the original printing range by several characters.
It has the disadvantage that it cannot be detected when the deviation is only a few pitches.

[Purpose of the invention]

In the present invention, by knowing in advance the relationship between position sensors set at several locations and position counters with respect to the carriage passing through the sensors, it is possible to prevent This solves the above disadvantages by calculating the difference between the position of the carriage and its normal position when the carriage is shifted by a few pinches, or generating an alarm. The purpose of this invention is to provide a device that can perform accurate printing.

[Structure of the invention]

The present invention detects the position of the carriage during the homing operation when the power is turned on and during the horizontal feed operation during printing in a serial printer that performs a white print operation while moving a carriage carrying a print head along the print line. This configuration includes sensor means for performing up-down counting of a position counter as the carriage moves, and means for controlling the movement of the carriage based on the count results.

(Description of Embodiment) Fig. 1 is an embodiment of the present invention, and is a block diagram showing an outline of the control method.When a print control unit 1 receives a print command, a print head is sent to the print head via a print drive unit 2. 3, and provides information on movement direction and distance to the 1-carriage drive unit 4 and position counter 6.Position counter 6
is 1 to the right with the home position position as the base fishing value 0.
When the carriage moves one pitch, it counts up, and when it moves one pitch to the left, it counts down and sends the current logical position of the carriage to the successive approximation section 7. The comparison unit 7 compares the logical position with the current physical position of the gear ridge obtained from the sensor unit 5, and if the physical position is outside the normal range, the carriage 8 is moved via the carriage drive unit 4. Correct the position or stop and generate an alarm.

Next, the relationship between the position color and sensor output is shown in Figures 2 and 3.
This will be explained in detail with reference to the drawings.

Figure 2 is a schematic diagram of the main parts when three cells are used.
FIG. 3 shows a relationship diagram between the position counter and the sensor output.

In the drawing, 11 is a platen, 12 is a print head, 1
3 is a carriage to which the print head 12 is attached;
14 is a mechanical frame, 15 is a stepping motor for driving a carriage, 16, 1'7'.

18 is a sensor using a Hall element, 16 is used as a left end sensor, 17 is a center sensor, and 18 is used as a right end sensor. After the power is turned on, the carriage 13 performs a homing operation and stops at the home position. With this position as a reference position O, the position counter 6 counts up when the phase of the stepping motor 15 is switched once to the right, and counts down when it is switched once to the left. Electric,
When the carriage 13 is first moved to the right at the printing speed after the power is turned on, and the small force of the left end sensor 16 changes from HIGHLEVEL (hereinafter referred to as uH#) to LOW LEVEL (hereinafter referred to as II L II). position counter 6
The value N1o of is stored. Similarly, the value N20 of the position counter when the output force of the central sensor 17 changes from "L" to H'"
, the value N of the position counter when changing from “H” to “L”
50. The output of the right end sensor 18 is el L II to 6H.
The value N40 of the position counter when it changes to `` is stored respectively.Next, the carriage 13 is moved to the left at the printing speed, and in the same way, N41, N31 + lN2 + lN11 are stored.
remember. The relationship between the sensor output and the position counter is shown in Figure 3 (a), (bl, (cl, (mountains).The Hall element used in the sensor has hysteresis, so the switching system between IIHFl and @LII is The position differs depending on the printing direction.

In the case where the moving range NW of the carriage during printing is as shown in FIG. 3(e), if the carriage is operating normally, the relationship between the position counter and the setting will be as shown in Table 1.

Therefore, the amount of carriage shift can be determined by checking the sensor output each time the phase of the stepping motor is switched and comparing the value of the position counter at the time the sensor output changes with the stored value.

If the carriage position shifts for some reason, the shift is detected at each sensor position, and an alarm is generated or the carriage is moved to compensate for the shift amount, preventing the carriage from running out of control and correcting the shift position. Can be fixed.

〔Effect of the invention〕

As explained above, according to the present invention, when the position of the carriage deviates due to physical factor pressure, accurate printing is possible by measuring the amount of deviation and quickly controlling the movement of the carriage. shall be.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an overview of a control system showing an embodiment of the present invention, Fig. 2 is a schematic diagram of the main parts of a serial printer, and Fig. 3 is a diagram showing the relationship between the position counter and sensor output. . 1... Print control section 2... Print drive section 3... Print head 4... Carriage drive section 5... Sensor section
6... Position counter 7... Comparison section 8... Carriage

Claims (1)

[Claims] In serial printers that perform printing operations while moving a carriage equipped with a print head along the print line,
a sensor means for detecting the position of the carriage during a homing operation when the power is turned on and a traversing operation during printing; a means for counting up and down a position counter as the carriage moves; A control method for a serial printer, characterized by comprising means for controlling the movement of a carriage based on the results.