JPS588354B2 - Serial printer carriage feeding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention allows the carriage feed amount per space in a serial printer to be changed arbitrarily, and also enables printing of voiced and semi-voiced marks from the center of type by feeding the carriage in half spaces. and
This invention relates to a carriage feeding method that has a simplified mechanism.

In conventional serial printers, when changing the spacing feed amount per character depending on the type of paper, for example, when switching between form paper and roll paper, ■ Carriage per space The feed amount is 2.54 mm for the former and 2.8 mm for the latter.
Therefore, the pulleys of the moke that drive the wire rope or belt for feeding the carriage have different diameters, and by replacing these pulleys, the amount of feed per space can be changed.

Therefore, a pulse motor with 200 pulses/cycle was used as a motor for driving the carriage, and 4 pulses were used to drive the carriage for a distance of 2.54 m.
If one space feed of m is performed, the diameter of the pulley will be 40.44 mm, but similarly, 4 pulses will feed 2. 8 When performing a 1 space feed of 1nn,
A pulley with a diameter of 44.58 mm is required, and even though the various control circuits for driving the motor 1 and the like are the same, the pulley must be changed over, resulting in a drawback that handling becomes extremely difficult.

In addition, conventionally, when printing subscripts such as voiced and handakuten, unlike other ordinary characters, the subscripts were printed without spacing to move the carriage.
When using a petal-shaped type head, the subscript position on the type finger must be at the upper right, away from the center, and the impact force of the printing hammer will be uneven on the printing area.
This had negative effects such as shortening the lifespan of type.

Furthermore, conventional homing control means for returning the carriage to the home position include a near-home detector that detects when the carriage enters a predetermined range with respect to the home position, and a near-home detector that detects that the carriage has reached the home position. A detector is installed, and the carriage feed is decelerated by the detection force of the near-home detector4.Furthermore, the carriage feed is stopped by the detection force of the home detector, which requires multiple detectors. Therefore, the structure of the mechanism and control circuit is complicated.

The present invention has the purpose of fundamentally eliminating the disadvantages of conventional methods, and selects the carriage feed amount per space by increasing or decreasing the number of stepping pulses applied to the pulse smoke.
The object of the present invention is to provide a very effective method for transporting a carriage in a serial printer that can perform homing control using only a single near-home detector.

Hereinafter, details of the present invention will be explained with reference to figures showing examples.

FIG. 1 is a perspective view showing the configuration, in which a pulse sending circuit 2 sends out stepping pulses in response to a command signal from an apparatus control circuit 1, and a driving circuit 3 generates a driving output based on this stepping pulse. Each phase excitation winding of the pulse motor 4 is sequentially excited by the drive output, and the pulse motor 4 is rotated in steps according to the number of step pulses.

When the pulley 5A rotates as the pulse motor 4 rotates, a belt 6, such as a toothed timing belt, stretched between the pulleys 5A and 5B rotates, and the carriage 7, which is locked to the belt 6, moves. do.

The carriage 7 is equipped with a moke 8 for type selection, which drives and rotates the type head 9.
When the type 11 formed at the tip of the type finger 10 comes to the printing position, the positioning hammer 12 operates to strike the type 11 and print at the printing position.

Note that a position detection plate 13 made of iron plate or the like is fixed to the carriage 7, and moves together with the carriage 7 to detect the permanent magnet 1.
4, a position detector 16 consisting of a reed switch 15, etc.
When the position detection plate 13 reaches between the two, the position detection plate 13 changes the magnetic coupling state between the permanent magnet 14 and the reed switch 15, turning the reed switch 15 on or off, which causes the carriage 7 to return to the home position. It is detected that the position has entered a predetermined range.

Also, when the carriage 7 reaches the home position,
Stopper 17 provided at a position to regulate the home position
It is intended to be applied to

Now, the number of steps required for one rotation of the pulse smoke 4 is given by the diameter of the P1 pulley 5A being D (7n.),
Feed amount per space is 2.54. When mm, the number of step pulses required to feed the carriage for one space is N.
,, feed amount per space is 2. If the number of step pulses required to feed the carriage by one space is N2 when the width is 8 mm, the following relationship holds true.

From equations (1) and (2), for example, the diameter D of the pulley 5A is 16. 1.
Assuming that the pulse motor 4 is 71 nm and has 200 steps/round, as is clear from equation (3),
The feed amount for 1 space is 2.54. As mm, this is 1
In order to send the space, it is sufficient to send ten step pulses from the pulse sending circuit 2.

In addition, mechanically, the configuration remains as described above, and 1 of equation (3)
Approximately 1.0236, if 11 step pulses are sent from the pulse sending circuit 2, a carriage feed of 2.79398 mm will be achieved, and the feed amount per space will be 2.79398 mm. 8
Compared to the case where mm is used, the error is 0.0 0 6
0.02 mm, which poses no practical problem at all.

Therefore, 10 or 11 pulses are each taken as a unit pulse, one of the unit pulses is selected according to the feed amount for one space, and a step pulse that is an integral multiple of this unit pulse is used to drive the drive circuit 3. If it is applied to the pulse motor 4 through the
Carriage feed can be performed with the feed amount for one space being m or 2.8 mm.

That is, if 10 unit pulses are multiplied by 80 as an integer, 10 x 80 = 80 characters/line will be printed, and if 11 unit pulses are multiplied by 72 as an integer, the difference will be 11 x 72.
=77 characters/line are printed.

On the other hand, when printing subscripts, if a half-unit pulse is provided, which is approximately 1/2 of the unit pulse number, and a step pulse that is an integer multiple of this pulse is given to the pulse motor 4, the carriage can be moved by half a space. will be realized.

In other words, if you select either 5 half-unit pulses or 6 half-unit pulses depending on the amount of feed for one space, and perform spacing using a step pulse that is multiplied by 1 as an integer, the As shown in Figure 2, the carriage is moved by half a space, and it is only necessary to print a subscript at this position.Since the subscript is printed from approximately the center of the type 11, the impact force of the printing hammer 12 is applied almost to the center of the type 11. It is possible to uniformly concentrate on the central part, to obtain clear printing, and to extend the life of the type 11.

Furthermore, after performing normal printing at the final end of a character line, it is sufficient to perform a half-space carriage advance before printing a subscript, and it is not necessary to print a character with a subscript after an operation such as a carriage return or line feed. do not have.

Further, homing control for returning the carriage 7 to the home position when the power is turned on is performed as follows.

When the power is turned on, etc., a homing command is sent from the device control circuit 1, which causes the pulse sending circuit 2 to send a stepping pulse in the counter-space direction to move the carriage 7 to the home position on the stopper 17 side. After phase switching is performed, the signal is transmitted.

Then, the drive circuit 3 drives the pulse motor 4 in response to the stepping pulse.
to move the carriage 7 in the opposite direction to the space.

When the carriage 7 enters a predetermined range provided several steps before reaching the stopper 17, the position detector 16 generates a detection signal from the position detection plate 13, which is applied to the pulse sending circuit 2.

Then, the pulse sending circuit 2 causes the carriage 7 to move to the stopper 1.
The drive circuit 3 sends out a preset number n1 of step pulses necessary to reach the carriage 7, thereby moving the carriage 7 further in the counter-space direction.
If the object reaches the stopper 17, it may collide with the object.

At this time, the number of stepping pulses n1 is determined based on the distance between the position detector 16 and the stopper 17, and
The time point when the step pulse reaches the stopper 17 and the time when the last pulse of the step pulse is sent are within a difference of only a few pulses in terms of the number of step pulses.

Further, when the carriage 7 reaches the stopper 17 and stops, if the pulse motor 4 is stopped at a rotational position due to excitation of a specific phase, the positional deviation of the carriage 7 can be corrected by idle rotation of the pulse motor 4.

After the carriage 7 is positioned at the home position as described above, a predetermined number n2 of stepping pulses are applied to the pulse motor 4 to move the carriage 7 in the spacing direction opposite to the stopper 17 and stop it at the printing start position. .

In other words, n2=0, that is, the position in contact with the stopper 17 may be set as the printing start position.

In addition, if the carriage 7 is within a predetermined range when the power is turned on, etc., once the carriage is moved in the spacing direction to deviate from the predetermined range, and then the same control as described above is performed, the accurate printing start position can be determined. can be determined.

The same applies to the case of return line feed, etc., but in this case, since the number of step pulses that moved the carriage 7 in the spacing direction is clear, the same number of step pulses as this number of step pulses are used to move the carriage 7 in the spacing direction. What is necessary is to move the carriage 7 in the direction.

FIG. 3 is a block diagram showing the details of the device control circuit 1 to the drive circuit 3. Unit pulses are converted into unit pulses by switches SW using dip switches attached to the preset counters PCT, PCT2 of the pulse sending circuit 2. In addition to setting the number of pulses according to the feed amount of one space based on the base, the number of pulses corresponding to the feed amount of half space based on the half unit pulse is set by switch SW2, and the number of pulses according to this setting is preset. Kaunk PCT1,P
When CT2 counts, the output BR is turned to "L" (low level).

On the other hand, the pulse generators PG1 and PG2 are constructed by cascading monostable multi-by breaks, etc., and when a trigger is input, the multi-by breaks at each stage successively generate a pulse of a predetermined width, and the output from each stage is ORed. By taking out the pulses through a gate or the like, a number of pulses corresponding to the number of constituent stages can be obtained continuously.

Therefore, when the subscript character discrimination circuit SCD generates the spacing command SC based on the given telegraph code, this causes the pulse generator PG1 to continuously generate pulses,
In order to give a pulse to the excitation phase distribution circuit EPD through the AND gate G1 and OR gate G3, which are in the ON state, the excitation phase distribution circuit EPD, which is composed of a plurality of flip-flop circuits, etc., sequentially sets each output to "L". , by inverting this with inverters IV, ~■■4 and turning on transistors Q1 to Q4, the drive output V
1 to v4 are sequentially grounded, current is passed through the windings of each phase of the pulse motor 4 to excite the motor 4, and the motor 4 rotates in the normal direction, so that the carriage 7 moves in the space direction.

However, the output pulses of the pulse generator PG1 are counted by the preset count PCT, and when the set count number is reached, the output BR° is set to "L", so the AND gate G1 is turned off. Pulse generator P
The output pulse from G1 is blocked, and the carriage 7 moves by a feed amount of one space and then stops.

This is because the subscript character discrimination circuit SCD uses the half space command HC.
The same is true when the output pulse from the pulse generator PG2 similar to the pulse generator PG1 is sent to the excitation phase distribution circuit EP via the AND gate G2 and the OR gate G3.
However, when the count of the preset counter PCT2 is completed, the AND gate G2 is turned off, and the carriage 7 moves by a feed amount corresponding to half a space and then stops.

In addition, homing control at power-on, etc. is performed by the device control circuit 1.
The homing command HM from
Latch circuit LAT such as flip-flop circuit by M
is set and its output becomes "H" (high level), so the AND gate G5 is turned on via the OR gate G4, and the separately generated shift pulse SP is sent to the excitation phase distribution circuit EPD via the OR gate G3. give to

On the other hand, a backspace command circuit BSC such as a flip-flop circuit is set by the homing command HM, and its output is given to the excitation phase distribution circuit EPD,
Since phase switching is performed in which the output generation order of D is reversed, the ON and OFF states of transistors Q1 to Q4 are reversed to that during spacing, the pulse motor 4 is reversed, and the carriage 7 is moved in the opposite direction to the spacing. do.

When the carriage 7 reaches a predetermined range, the position detector 16 generates a detection force, and the latch circuit LA. In order to reset T and give it to the start input ST of the reset counter PCT3, the counter PCT3 starts counting clock pulses CL that have a specific phase relationship with the shift pulse SP, When the number of pulses set by switch SW3 is counted,
The output BR is generated as "H".

The output BR is given to the OR gate G4 via the AND gate G6 which is in the on state, and because the AND gate G5 is maintained in the on state, the shift pulse SP resets the latch circuit LAT. The pulse SP is continuously applied to the excitation phase distribution circuit EPD, and the pulse motor 4 continues to reverse rotation.

That is, after the detection force is generated by the position detector 16 and until the counting of the preset counter PCT3 is completed, the necessary number of step pulses are applied to the pulse smoke 4, and the carriage 7
reaches the stopper 17, but even after that the shift pulse S
P causes the pulse smoke 4 to rotate idly.

The excitation phase distribution circuit EPD generates the output EP as “L” when its output reaches a specific excitation phase condition, so the AN
D gate G6 is turned off, and thereby AND gate G5 is also turned off, preventing transmission of shift pulse SP.

Therefore, the pulse smoke 4 stops at a rotational position caused by a specific excitation phase, and the output of the AND gate G6 becomes "H".
” to “L”, the backspace command circuit ESC is reset, and the excitation phase distribution circuit EPD is restored to its initial state.

At the same time, the output EP causes the pulse generator P to
A pulse generator PG3 using a pulse generation circuit and a counter similar to G1 and PG2 generates a predetermined number of pulses and supplies them to the excitation phase distribution circuit EPD via an OR gate G3, so that a predetermined number of progressive pulses are generated. It is sent to the pulse smoke 4 and stops after the carriage 7 reaches the printing start position.

In addition, AND gates G1, G2, G,
, G6 may be used as an AND gate depending on the conditions, and OR gates G3 and G4 may also be used as NOR gates. It is also possible to perform the following operations, and various modifications are possible.

As is clear from the above explanation, according to the present invention, the spacing between spaces can be changed only by operating a switch without changing the mechanism, and subscripts such as voiced and half-voiced marks can be printed from approximately the center of the typeface. Therefore, the life of the type is extended and the printing is clear.

In addition, a single position detector is sufficient to detect the position of the carriage, the mechanism can be easily simplified, and the printing start position can be accurate, providing great benefits in serial printers for various uses.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a perspective view showing the configuration, Fig. 2 is a drawing showing the printing situation, and Fig. 3 is a block diagram showing details of the device control circuit or drive circuit in Fig. 1. It is. 1... Device control circuit, 2... Pulse sending circuit, 3... Drive circuit, 4... Pulse motor, 5A, 5B... Pulley,
6... Belt, 7... Carriage, 10... Type finger, 11... Type, 12... Printing hammer, 13... Position detection plate, 16... Position detector, 17... Stopper, SC
D...Subscript character discrimination circuit, PG1-PG3...Pulse generator, PCT1-PCT3...Breset counter,
SW1 to SW3...Switch, EPD...Excitation phase distribution circuit, ESC...Backspace command circuit.

Claims (1)

[Claims] 1. In a serial printer in which the carriage feed is driven by a pulse motor, a plurality of unit pulses with different numbers of pulses are provided, the unit pulse is selected according to the feed amount of one space, and the unit pulse is set as an integer multiple of the unit pulse. A stepwise pulse is applied to the pulse smoke, and a half-unit pulse is provided, the number of which is approximately 1/2 of the number of pulses of each unit pulse, and the half-unit pulse is selected according to the feed amount of the half-space, and the half-unit pulse is A step pulse that is an integral multiple of the pulse is applied to the pulse motor, and a near home zone is detected to detect when the carriage enters a predetermined range with respect to the home position, and the home position is regulated by the detection signal. A stepping pulse is applied to the pulse motor to cause the carriage to reach a stopper provided at 1. A method for feeding a carriage in a serial printer, characterized in that a predetermined number of stepping pulses are applied to the pulse smoke to cause the carriage to move.