JPS6023070A - Blank delivery mechanism in shuttle type dot line printer - Google Patents

Abstract

PURPOSE:To prevent the longitudinal size of upper part of the first line after restarting printing from being lessened, by providing the platen reversing measures rotating a platen in the direction reversal to the delivery direction of blank by the interlock with the printing head driving motor. CONSTITUTION:When a printing starting command is input to a printer treatment circuit 40, a platen reversal motor 34 and a printing head reciprocation driving motor 15 are driven. A platen 4 is reversely rotated by the drive of motor 34, a blank 7 being sent downward by the frictional force between the platen 4 and the blank 7 and the loosened blank 7 is tightened. The reciprocation to right and left of printing head 11 is started via a fly wheel 16 and a connecting rod 12 by the drive of motor 15. When the speed of printing head 11 reaches a specific one, printing is started.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a paper feeding mechanism in a shuttle type dot line printer.

(Background of the Invention) As is well known, paper feeding in dot line printers is performed by a tractor. Therefore, when printing is being performed regularly (paper feeding), the paper is under tension due to the traction force of the tractor and the frictional force held under pressure by the platen and the paper press plate.

By the way, in a shuttle-type dot line printer, when printing is interrupted, the print head reciprocates left and right for a short time immediately after paper feeding stops (tractor stops), and then stops. Next, when a print restart command is issued, the print head starts reciprocating motion and is accelerated until it reaches a predetermined speed. Then, when the reciprocating movement of the print head reaches a predetermined speed, printing starts. Therefore, while printing is interrupted, the paper is not being pulled by the tractor, and the holding force between the platen and paper press plate, which holds the paper, is reduced due to the vibrations generated by the reciprocating movement of the print head. When the paper is restarted, the paper that was under tension becomes loose. When printing is restarted in such a state, the tractor pulls the paper by one dot pitch after printing the first dot row, but
It mainly only tensions the paper between the tractor and the platen, and the part of the paper facing the printing stylus hardly moves. Therefore, the second dot row is printed overlapping the first dot row. When the paper is pulled a second time by the tractor, the paper becomes even more tensioned.
Although it moves more than the first time, it is shorter than the predetermined feed amount. From the third time onwards, it is moved by approximately the predetermined amount. Therefore, as shown in FIG. 3, the printed result is that the vertical dimension above the characters is shortened in the first line after printing is resumed.

(Object of the Invention) An object of the present invention is to provide a paper feed method for a shuttle type dot line printer that prevents the vertical dimension of the upper part of the first line from being shortened after printing is resumed by interrupting printing. There it is.

(Embodiment of the Invention) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. As shown in FIG. 1, left and right side plates 2.3 are fixed to the bottom surface of the base 1 so as to face each other on the rear side. A platen 4 is rotatably supported on the lower front side of the left and right side plates 2.3. Above the platen 4 are left and right side plates 2.
A guide rod 5 fixed to the left and right side plates 2.3, and a tractor drive shaft 6 rotatably supported on the left and right side plates 2.3 are disposed.

These guide rods 5 and the tractor drive shaft 6 have a tractor 8 that engages with the perforation 7a of the paper 7 and feeds the paper 7.
．． 9 is slidably disposed. Also, left and right side plates 2.3
A paper chute 10 is fixed to the paper chute 10 for guiding the paper 7 to the outside of the apparatus at the rear.

A print head 11 that is slidable in the left and right direction is disposed facing the front ζ of the platen 4, and one end of a connecting rod 12 is rotatably attached to the print head 11. Further, a slidable movable portion 13 is disposed on the right side of the print head 11, and one end of a connecting rod 14 is rotatably attached to this movable member 13 as well. The other ends of the two connecting rods 12 and I4 are eccentrically and rotatably attached to a flywheel 16 fixed to the output shaft of a motor 15 for reciprocating the print head.

Further, a sensor disk 17 for controlling the rotation of the motor 15 is fixed to the rotation shaft of the motor 5 for reciprocating the print head.
A sensor 18 is fixed to the base II so as to sandwich this sensor disk 17. The motor 15 is connected to the base 1
is fixed to a lower partition wall 19 provided on the bottom of the
Cooling fans 20 and 21 are attached to the lower partition wall 19 by cutting out a portion thereof and facing the printing/rad 11.

As shown in FIG. 2, a paper insertion groove 1a is formed in a portion of the base 1 below the platen 4, through which the paper 7 passes.

On the back side of the base 1, there are a front paper chute 22 that guides the paper 7 from the front (front) of the device to the groove 1a, and a rear paper chute 23 that guides the paper 7 from the rear of the device to the groove 1a. It is fixed with a certain gap from the back side. A gap 24 is formed at the end surfaces of the front paper chute 22 and the rear paper chute 23, so that the paper 7 can be inserted into the groove 1a from below. That is,
Paper 7 is a force in any of the three directions: forward, backward, and downward)
They can also be inserted into the device through the groove 1a. The figure shows the case where paper 7 is inserted from below. Further, a paper press plate holder 25 fixed to the left and right side plates 2.3 shown in FIG. A press plate 26 is fixed.

Returning to FIG. 1 again, a paper feed motor 30 is mounted on the side plate 3.
is fixed, a drive pulley 31 fixed to the output shaft of this paper feed motor 30, and a paper feed boo 'J32c! fixed to the tractor drive shaft 6! : The belt 33 is attached to the belt. An output shaft of a platen reversing motor 34 fixed to the side plate 3 is connected to the platen 4, and this platen reversing motor 34 works in conjunction with the print head reciprocating drive motor 15 to move the platen 4 in the paper 7 feeding direction. The morph 15 for reciprocating the print head is connected to a printer processing circuit 40 built in the printer device so as to rotate the print head in the opposite direction. The printer processing circuit 40
are the driver circuit 41 and control circuit 4 of the motor 15.34.
2, an input buffer 43, and an interface 44, and is connected to a computer 45.

The next ζ action will be explained. During printing interruption, the paper 7 between the tractor 8.9 and the platen 4 is in a relaxed state, as explained in the background section above. When a printing restart command is input from the computer 45 to the printer processing circuit 40, the platen reversing motor 34 and the print head reciprocating motor 15 are driven. Platen reversing motor 3
4 is driven, the platen 4 is rotated in the opposite direction B to the feeding direction A of the paper 7, and the friction force I between the platen 4 and the paper 7 sends the paper 7 downward, causing it to become loose as described above. Tension paper 7. Also, the print head drive motor 1
5 is driven, the print head 11 starts reciprocating from side to side via the flywheel 16 and connecting rod 12, and when the print head 11 reaches a predetermined speed, it starts printing by a well-known method. After printing the first dot row, the paper feed motor 30 is activated and the pulley 31 and belt 3 are driven.
3. The tractor drive i11+6 is rotated via the pulley 32, and the paper 7 is pulled by one dot pitch by the tractor 8.9.

In this way, since the paper 7 is under tension when printing is restarted, the pitch of the dots becomes a predetermined amount from the first time, as shown in FIG. 4, and as shown in FIG. The vertical dimension at the top of a row is never shortened.

In the above embodiment, the platen 4 was driven by a dedicated platen reversing motor 34, but the print head reciprocating,
A drive motor 15 is used to drive the pulley,
It may also be rotated via a belt or the like. .

(Effects of the Invention) As is clear from the above description, according to the present invention, a platen reversing means for rotating the platen in a direction opposite to the paper feeding direction in conjunction with the print head drive motor is provided, so that printing When restarting, the paper is tensioned and the first
The vertical dimension at the top of the row is prevented from shrinking.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a side view schematically showing a paper path, and FIG. 3 is a conventional printing pattern. This is a map of the temple. 4...Platen, 7...Paper, 7a...Perphonosion, 8.9...Tractor, 11...Print head, 15...Print head drive morph, 34...Platen Reversing motor. Figure 3 Figure 4

Claims (1)

[Claims] a rotatably disposed platen; a print head disposed opposite to the platen so as to be slidable in left and right directions;
In a shuttle type dot line printer, which is equipped with a print head drive motor that drives the print head back and forth, and a tractor that engages with a par 7 oration of paper to feed the paper, the print head drives the print head in conjunction with the print head drive motor. A paper feeding mechanism for a shuttle type dot line printer, characterized in that a platen reversing means is provided for rotating the platen in a direction opposite to the paper feeding direction.