JPS58160178A - Controlling system for space - Google Patents

Abstract

PURPOSE:To attain the titled system which can prevent a printing head from printing outside the printing range of a printing paper sheet and from running abnormally, by stopping the printing head at a reference point in the direction of a column when a photosensor detects a shielding plate in reverse-direction printing. CONSTITUTION:When printing in the normal direction is completed and feeding for a new line is conducted, a reverse-rotation instruction is delivered from a control circuit unit 8 and sent via an OR circuit 5a. Based on this instruction, a step motor 19 is rotated reversely by a normal-reverse rotation controlling unit 7, while an FF circuit 4b is set thereby. A printing head 21 performs reverse-direction printing, while moving in the direction of an arrow C according to printing data signals from the control circuit 8. When a photosensor 2 detects a shielding plate 1, a signal is given to an AND circuit 6. Then a stop instruction is delivered therefrom, the step motor 19 is stopped by the normal-reverse rotation controlling unit 7, and thus the printing 21 is stopped at a position whereat it is at that time.

Description

[Detailed Description of the Invention] (Technical Field of 11 Ij!) The present invention relates to the space control of the print head of a serial printer, and in particular, to prevent the print head from printing outside the predetermined area of the paper, or from running out of control. Concerning prevention of alteration of space control system.

(b) Background of the Technology In recent years, serial printers have been developed and put into practical use as terminals for various computer systems and office machines such as word processors. In particular, as its use as an office automation machine is expanding, printing speeds and print quality are increasing.
There is a need to improve the reliability of printing operations as well as maintenance.

(C) Prior Art and Problems Hereinafter, a conventional method will be explained using a wire tod printer as an example with reference to FIGS. 4 to 3. Fig. 1 is a plan view illustrating the outline of a wire tod printer to which the present invention is applied. , 15 is a guide shaft, 16 is a feed screw, 17 is a belt, 19 is a step motor, 20 is an ink ribbon cassette, 20m is an ink ribbon, and 21 is a print head.

The wired top printer has side 7 frames 9 as shown in 11th II), ? A platen Io is rotatably supported on the side frame 9.

The printing paper 11 is wrapped around the platen lO.
The printing paper 11 is sent in the direction indicated by the arrow in the figure by sprockets 12m and 11b. On the other hand, in front of the platen 1O, that is, in the lower part of the figure, a carrier 13 is slidably fitted into a guide shirt 15 provided parallel to the platen 1O.
? ), the carrier 13 is similarly provided parallel to the platen lO and is threadedly engaged with a forward screw 16. The feed screw 16 is connected to a step motor 19 via a belt 17 etc.], so the feed screw 16 moves the carrier 13 in the directions of arrows 0 and D in the figure by the forward and reverse rotation of the step cage 19. can be done. Career! An ink ribbon cassette 20 is mounted on the cassette 20, and an endless ink ribbon 20a is built into the cassette 20 with 70 parts exposed to the platen member side. 9. The print head 21 is attached to the carrier 13.
The print head 21, which is installed in an L-shape, is provided with a plurality of print magnets for forming prints using dots. Usually, 1 to 24 printing magnets are provided.

9. Side frame 9km near the left end of platen lO
A photo sensor 2 is attached to a middle plate 13 on which a printing head 21 is mounted and a printing head 21 is mounted. The photosensor 2 is designed to detect the presence of the shielding plate 1 at the tip of the shielding plate 1, at the right end in the figure, and is connected to a device control unit KI [11! has been done. During printing, even if the photo sensor 2 detects the value 1i[1, the device control section does not detect it.

With this configuration, when the printer is turned on, the print head 21 stops and moves from the initial position to the home position at the left end in the figure (due to the printer's initial operation), but at this time the photo sensor 2 Detects the right edge of shield 1 [1 and stops. Using this position as the home position, ie, the digit reference point for starting line printing, the stepper printer 19 is rotated by a print command pulse from the apparatus control section, the print head 21 is moved, and the print position is controlled. The print head 21 operates: Then, the ink ribbon 2 is applied to the print paper 11 on the platen member.
0a, the printing wire of the printing magnet is centered and printing is performed, and as shown in Fig. 2-)K, the printing head 2
1a Printing is performed on the printing paper 11 while moving in the direction of the arrow with the carrier 13.

- When the printing of the character is completed, the printing paper 11 is moved in the direction of the arrow by a predetermined amount of tension at the ninth line break. The print head 22 then continues printing while moving in the direction of arrow C.

However, according to this method, if an abnormality occurs in the mebase system while printing in the forward direction of the print head 21 (rightward in the figure), in other words, zero pressure is applied from the outside or the mechanism is abrasive, etc. In some cases, as shown by the hatching a in Figure 2(b), the printing at the right end of the stroke may be distorted and not be printed all the way to the end of the line. For this reason,
Printing in the opposite direction, to the left in the figure, is performed from that position, so even when the home position is reached, the print head 21 moves to the left edge of the printing paper 11. It is possible that the carrier 13 may run out of control and hit the side frame 9 and make a loud noise), or the mechanical parts may deform and malfunction. However, as shown by the hatching b, there are various drawbacks when the black letters t and b are printed on the left edge of the printing paper.

(d) Invention The object of the present invention is to eliminate the above-mentioned drawbacks, and to prevent the print head from printing outside the printing width of the printing paper and running out of control. K provides a control method
be.

(e) Structure of the Invention The present invention comprises a platen member, a printing section including a print head facing the platen member with a gap therebetween, and a drive section for moving the printing section in parallel to the shaving of the platen section. Narushi,
In a printer in which a printing unit is reciprocated by the driving unit and is set in a gap between the printing unit and the platen member and prints on a nine-medium during a return operation, the printing unit is provided in a control unit that controls the printing position. Drive stop command means;
A printing section provided at one end of the drive section has a detector that detects that it is present at a starting end, and the detector detects the starting position during a period when the printing section performs the reciprocating printing on the medium. This space control system is characterized in that, when this happens, the drive section is stopped in response to a command from the drive stop command means. By doing so, we will meet to achieve our purpose.

(f) Embodiment of the Invention An embodiment of the present invention will be described below with reference to No. 3511 and No. 4!111. FIG. 3 is a block diagram showing an embodiment according to the present invention 11, and FIG. 4 is a diagram showing the fourth stage of stopping the reverse space operation in step 311. In the figure, 3 is the power-on detection section, 4m and 4b are the lift cup circuit% 5
m+5b is an OR circuit, 6 is an AND circuit, 7 is a forward/reverse control section, 8 is a control circuit section, and %8m is a driver. The same parts as in FIG. 1 are indicated by the same symbols.

FIG. 3 shows the space control circuit of the print head 21 of the device control unit. When the printer is turned on, a command is issued from the power-on detection unit 3 to flip the flip circuit 4 a.
(Flip Flop S, hereinafter referred to as Fl' circuit) is set, and enters the forward/reverse control section 7 via the OR circuit 5a to rotate the step motor 19 in the reverse direction to move the print head 21 in the direction of the initial position, ie, in the direction C in the figure.

On the other hand, the command from the power-on detection section 3 is transmitted to the AND circuit 6 via the OR circuit 5b. When the photo sensor 2 attached to the carrier 13 detects the shielding plate l, a signal is sent to the AND circuit 6, a stop command is issued, the forward/reverse control unit 7 stops the step motor 19, and the print head 21 completes the initial position stop. do. The stop command notifies the control circuit section 8 of completion of the initial position and also resets the KFF circuits 4m and 4b. Next, as a printing operation, a forward rotation command is issued from the control circuit section 8, and the forward/reverse control section 7 rotates the stepper 19 in the forward direction to move the print head 21 in the forward direction, in the direction indicated by the arrow in the figure. Similarly, a print data signal is outputted, passes through the driver 9, causes the print head 21 to perform a printing operation, and printing in the forward direction is performed.

When printing in the forward direction is completed and a line feed is performed, a reverse command is issued from the control circuit section 8, and the step motor 19 is rotated in the reverse direction by the forward/reverse control section 7 via the OR circuit 5m. Set the FF circuit 4b.

The print head 21 performs reverse printing while moving in the direction of arrow 0 in response to a print data signal from the control circuit section 8. When the photo sensor 2 detects the covering plate 1, a signal is sent to the AND circuit 6.
, a stop command is issued, the forward/reverse control unit 7 stops the step motor 19, and the print head 21 stops at that position. Space operation stop for this reverse direction printing 071
- is shown in FIG. In this way, while the reverse command from the control circuit 8 causes the step motor 19 to reverse, the FF
Since the circuit 4b and the OR circuit 5 cause the AND circuit 6 to wait for the detection signal from the photosensor 2, the print head 21 during reverse printing prints l! Even if there is an I mark, printing can be stopped and stopped at the digit direction reference point for starting line printing.

(g) As described in detail, according to the present invention, in reverse direction printing, the photo sensor detects the cover plate and stops the print head at the digit direction reference point even if there is a print residue during printing. Therefore, it is possible to prevent ``C'' printed on the left margin of the printing paper and a black ``T'' printed in the same position.

In addition, at this time, it is possible to prevent the carrier from making a sound due to collision with the side frame, or from deforming and breaking down the mechanical parts.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating the general cost of a wire tod printer to which the present invention is applied, and FIG.
FIG. 3 is a block diagram showing an embodiment of the present invention, and FIG. 4 is a flowchart of stopping the reverse space operation in FIG. 3. In the figure! is a layered plate, 2 is a photocell, 3 is a power-on detection section, 4m, AbdFFli path, 5a. 5b is an OR circuit, 6 is an AND circuit, 7 is a forward/reverse circuit section, 8
8a is a control circuit, 8a is a driver, 13 is a carrier, and 21 is a print head.

Claims (1)

[Claims] Consisting of a platen member, a printing unit including a print head facing the platen member with a gap therebetween, and a drive unit that moves the printing unit parallel to the plant member, the drive unit moves the printing unit back and forth. In a printer that prints on a medium set in a gap between the printing section and the platen member during reciprocating operation, the control section for controlling the printing position includes a circle printing section movement stop command means, and a driving section of the first drive section. A detector provided at one end detects that a printing section is present at a starting end, and when the detector detects the starting position during a period in which the printing section performs reciprocating printing on the medium, The drive stop command: a space control system characterized in that the drive unit is stopped (by a command from a command means).