JPS58188682A - Mechanism for determining position of printing head - Google Patents

Abstract

PURPOSE:To make it possible to maintain the original printing gap when a printing head is restored after retracted to set paper and to exchange an ink ribbon, by carrying out the adjustment of a printing gap and the retracting operation of the printing head by separate mechanisms. CONSTITUTION:When a printing gap (a) is adjusted, a knob 5 is rotated to move a dog plate to a uertical direction while a slide plate 7 engaged with the recessed part 1a thereof rotates an eccentric shaft to a direction ML while a printing head 21 is brought close to and parted from a platen 10 through a slider part 13b and a stut 13c. When paper 11 is set and an ink ribbon 20a is exchanged, a lever 22 is rotated to a direction H to turn a microswitch 14 OFF while a slide plate 7 is moved to a direction J to disengage a protruded part 7a and the recessed part 1a and a rotary plate 6 is rotated to a direction L while the eccentric shaft 16a is rotated to the same direction to part the head 21 from the platen 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a print head for a serial printer such as a wire tod printer, and relates to an improvement in a print head positioning mechanism that facilitates the operation of the print gap O11. .

(b) Background of the Technology In recent years, serial printers have been developed and put into practical use as terminals for various combiators and office machines such as word processors. These printers usually print by wrapping printing paper around a platen and setting an ink ribbon between the printing paper and the print head, but it is easy to set the printing paper and ink ribbon. As the use of desirable word processors and the like is expanding, there is an increasing demand for ensuring print quality.

(e) Prior Art and Problems Below, the conventional method will be explained with reference to FIGS. 2 is a side view showing the printing section and carrier section shown in FIG. 1, and FIG. 3 is a station top view showing the printing gap adjustment section shown in FIG. 1I82.

As shown in Figure II1, the wire tod printer has a side frame 9, on which a platen IO is rotatably supported.

A printing paper 11 is wrapped around the platen 10.
The printing paper 11 is sent in the direction of arrow A in the figure by sprockets 12m and 12b. On the other hand, on the front side of the platen IO, that is, on the lower side in the figure, a carrier 13 is screwed into a feed screw 15 provided parallel to the platen 10.
is similarly slidably fitted into a guide shaft 16 provided parallel to the platen 10. The feed screw 15 is wall-mounted to the motor 19 via a belt 17, etc. Therefore, the feed screw IIs can be moved in the directions of arrows C and D in the figure of the carrier 131 by the forward and reverse rotation of the motor 19. An ink ribbon cassette 20 is mounted on the carrier 13, and an endless ink ribbon 2 is mounted on the cassette 20.
A print head 21 is installed in the carrier 13 so as to be attached to an ink ribbon cassette 20. A plurality of printing magnets (not shown) are provided in order to generate printing sound by dots.

With such a configuration, when the print head 21 operates, the print wire of the print magnet collides with the print paper IN on the platen 10 shown in FIG. 21 is the printing paper 11 while moving in the direction of the arrow along with the carrier 13.
When printing for one line is completed, the printing paper 11t is pulled in the direction of arrow A by a predetermined amount of tension for line feed.
Transfer this. Then, the print head 21 prints tl! while moving in the direction of arrow C. Continue.

In some printers, the platen 10 and print head 2
In order to ensure printing quality, the gap at the tip of the printing paper 11, that is, the printing gap a, is determined by the thickness and number of printing paper 11 used.
Also, it is necessary to adjust the optimum value depending on whether pressure-sensitive paper or carbon paper is used. For example, when printing paper 1 is stacked from 1 to 5 sheets, the printing gap 1 is adjusted within the range of 0.2 to 0.6cm, and in order to obtain good printing quality, the printing gap 1 is adjusted within the range of ±005mm.
The print head 21i is retracted for easy operation when setting the printing paper 11 or replacing the ink ribbon, which requires a sieve accuracy of 1°01.
I am taking *t- for the above period. Next, to explain how to adjust this printing gap a, as shown in Fig. 2,
The yfA portion of the guide shaft 16 is supported by the side frame 9 by an eccentric shaft 16m having a smaller diameter than this, and the carrier 13 is composed of a carrier front portion 13 and a slider portion 13b, and the carrier front portion laa is A print head 21 and the like are mounted and screwed onto the feed screw 15. The slider 1ffl13b is fitted into the guide shaft 16. A connecting portion between the carrier front portion 13m and the slider #I 3b is slidably fitted into a hole 13d provided in the stiff 13ct-slider portion 13b provided in the carrier front portion 131. As shown in FIG. 3, a lever 14 is attached to the tip tC of the eccentric shaft 16m.
When the lever 14 is rotated in one direction, the eccentric shaft 16m rotates, and the guide shaft 16 rotates accordingly.Then, the fixing spring 18. ~
18. and 1g are provided.

Since it has such a configuration, when the lever 14i is articulated with the printing gap 1, the eccentric shaft 16m rotates and the guide shaft 1 is rotated in the direction of the arrow E.
6 rotates and Jl! Slider part 1 of carrier 13 in Figure 2
3b, since it moves in the direction of arrow G in the figure, the front @laa of the carriage 7 can be partially reduced by the size t of the print gap a with the feed screw 151 as the center. In this way, the printing gap a can be adjusted, the printing paper 11 can be set, and the printing head 21 can be retracted for replacing the ink ribbon 20m.

However, with this method, the problem is that a certain print cap a is making a printing noise, the print paper 11 set h is evacuated, and then returned to the original print gap a after setting and replacement. In other words, there are many cases where the operator has to remember the position of 4. In other words, there are many cases where the operator must remember the original print gap a'7R, operate the lever 14, and then set the optimum print gap a again. To obtain the test mark, you must repeat the trial print from the side entrance.

(d) Object of the Invention The object of the present invention is to solve the above-mentioned drawbacks, and to provide a print head positioning mechanism that allows the printing gap during printing to be stored in the device.

(・) Structure of the Invention In the present invention, the means for adjusting the gap between the platen and the print head includes a lever member provided on the eccentric shaft of the guide shaft 0111Is that guides the carrier, a dog member having a concave portion, and a receptacle for the dog portion. A moving means is provided, and the distal end of the lever member is engaged with the concave portion, and the moving means moves the entire dog member and rotates the eccentric shaft by rotation of the lever member. This is a print head positioning mechanism characterized by: By doing this, the target sound S can be created.

(f) Embodiment of the Invention Hereinafter, an embodiment of the invention will be described with reference to FIGS. 4 and 5. FIG. 4 is an 11th view showing an embodiment according to the present invention;
FIG. 5 is a diagram showing the operation of FIG. 4.

As shown in FIG. 4, a screw block 2 having a screw hole 2ak is added to a dog plate l having a -1fil recess, and a feed screw 3 having a gear 3 at one end is screwed into the screw hole 21. . The gear 81 meshes with a gear 4a attached to the shaft 4, and a rotary knob 5 and a scale plate 5a are provided coaxially. Shank part 3b of feed screw 3
and the shaft 4 is a frame 9 attached to a side frame 9.
It is supported by a. The screw block 2 is pulled downward 1 in the figure by a pre-H hexagonal screw 2a. Therefore, when the rotary knob 5 is turned -, the dog plate 1 moves up and down t.

On the other hand, a rotating grate 6 is fixed to the end of the eccentric shaft 16a, and a sliding portion 6 a I provided on the rotating plate 6
A slide plate 7 is slidably attached thereto. On the leading edge of the slide plate 7, there is a milk-shaped convex portion 71.
A long hole 7b is provided in the center, and studs 7e and 7d are attached to the other end. The convex portion 7a is slidably fitted into the U-shaped concave portion 11 of the dog play 1, and is engaged with the convex portion 7a in the vertical direction in the figure. long hole 7
Four ends of the eccentric shaft 16a are slidably fitted into the shaft.

In the rotating plate 60 diagram, the right end and the stud 7d
They are connected by a force spring 6c, and the elasticity of the force spring 6c biases the slide grate 7 in the direction -c in the direction of the arrow in the figure.

In addition, a stud 6b is provided on the rotating plate 6J, and a stud 9b is attached to the idle frame 91.
It is slidably fitted into a long hole 81 provided in the lever 8 which serves as the fulcrum. A spring 6c is attached to the stud 6b and biases the rotating grate 6'kg IA core shaft 16at in the direction indicated by the arrow in the figure. The lower part of the rotating plate 6 includes a hold cam 6d and a stop portion 6.
e is formed. Furthermore, in the upper left corner of 1crlJ, an inverted lever 22 is provided as a fulcrum at the corner of a stud 9at attached to the side frame 9. The lower end of the lever 22 is formed with a U-shaped notch, and
A cam follower 22m is formed, and a notch 221i
11 is engaged with the stud 7c of the slide plate 7. In addition, a recovery spring 22e is provided that biases the lever 22t in the direction of arrow S in the figure, and the horizontal s1 of the lever 22 is pushed! 1i22d are provided.

The horizontal end of the lever 22 is in contact with the operating lever 14m of the microswitch 14 attached to the frame 9a,
When the pushbutton 22d is pushed down in the direction of the arrow G in the figure, the operating lever 14m is configured to completely disengage the contact 14b. The microswitch 14 is connected to a control section (not shown), and when the contactor 14b is restored, the connection becomes 0FFl, and all mechanical operation functions raFr are performed.

With such a configuration and function, printing gap 1
1111, turn the rotary knob 5 clockwise as shown in Fig. 4, the dog plate 1 will move downwards, and as explained in the figure of the protrusion engaging the recess 1m, printing will be performed. The gear 3m is set so that the printing gap a will approximately fit, for example, sheets 1 to 6 of the printing paper 11 with one rotation of the 0-rotation knob 5 that changes in the direction in which the gap a widens.
If a conversion ratio of 4 m is set, a scale corresponding to the scale plate 5a can be carved. First, print gap a according to the scale.
t-setting and printing, and if further adjustment of drying is required, fine adjustment can be made with the rotary knob 5.

Also, the set of printing paper 11 is 20m of ink ribbon.
When holding an exchange meeting, move the lever 22 to 1 as shown in Figure 5.
When the lever 22 is pushed in the direction of arrow G in the figure, the lever 22 rotates in the direction of arrow H in the figure. Micro switch 14 is OFF
At the same time as F, the slide plate 7 moves in the direction of the arrow J, the engagement between the convex s7 and the concave @1m is disengaged, and the recovery spring 6c rotates together with the rotating plate 6 in the direction of the arrow ff1L in the figure. , the eccentric axis I Sak rotates in the same direction.

At this time, the stud 7c is disengaged from the notch 22b of the lever 22, the hold cam 6d comes into contact with the cam follower 22a and slides, and the rotation is stopped at the stop portion 6. The print head 21 is retracted to a predetermined position by the rotation angle of the eccentric shaft 16a, so that the print paper 110 can be set or the ink ribbon 201 can be replaced.

At this time, the lever 8 indicated by the center line of chain tightening 14 in the figure moves in the direction of arrow Q during the period due to the movement of the stud 6b in the N direction in the figure, and rotates to the position indicated by the center line of point 1 am. . That is, the lever 8 moves by a distance indicated by the 1ζ 2-point line in Fig. M4.

When you finish setting the printing paper 11 or replacing the ink phone 20a and want to return to the original printing gap color, press #! 5
In the figure, when the lever 8tlEl is rotated in the direction of the arrow R in the figure, a force is applied to return the stud 6b in the direction of the arrow P in the figure, rotating the rotation play) 6 in the direction of the arrow M, and the stud 7C of the slide plate 7 is rotated again. Notch 2 of lever 22
2b and returns to the position of the concave part 1a of 1 (convex @ 7 m is dog gray) 1, the slide plate 7 is pulled in the direction of arrow mK in the figure by the elasticity of the force spring 6c, and the convex s7
A is engaged with the recess la, and the wiping movement I shown in FIG. 1 returns to its original state. Therefore, since the position of the recess 11 of the dock plate 1 corresponding to the original printing gap a is returned, printing can be started with a proper printing gap a.

(g) Detailed Description of the Invention According to the present invention, the adjustment of the print gap a and the retraction of the print head can be performed using separate mechanisms with separate sounds, and moreover, the print head can be retracted to set the print paper or to retract the print head. When the ink ribbon is old again after replacing the ink ribbon, the original printing gear can be obtained, so there is no need to remember the original printing gap lever setting, and the operation is easy. Since l1w4 adjustment can be performed for gap adjustment, there is an effect that printing quality can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an outline of a wire tod printer to which the present invention is applied, FIG. 2 is a side view showing the printing section and carrier section of FIG. 1, and FIG. Figure 4 is a side view showing the embodiment of the present invention, and Figure 5 is #! This is theory #4 diagram showing the effect of Figure 4. In the figure, l is a dog plate, 1m is four parts, 2a is a screw hole, 3.15 is a feed screw, 5 is a rotating knob, 5m is a scale plate, 6 is a rotating plate, 6a is a slide part, 6b,
7cm stud, 7 is slide plate, 7a is convex part, 7b, 8m is long hole, 8° 14.22 is lever, 10 is platen, 11 is printing paper, 13 is carrier, 13m is carrier front, 13b is Slider section,] 6 is a guide shaft, 16a is an eccentric shaft, 20m is an ink ribbon, 21 is a print head, 22b is a cutting section. No.

Claims (1)

[Claims] A platen member, a printing unit including a print head facing the platen member via 1vt, and the printing unit! The receiver is moved perpendicularly to the platen member and the receiver is placed on the platen. In a printer that prints on a medium set in the gap that is received from a drive unit that moves the carrier parallel to the platen member, the means for adjusting the gap is arranged in the front F. A lever member provided with an eccentric shaft at the end of the shaft member for guiding the inner shaft, a dog member having a recess, and means for moving the dog member, the tip of the lever member in the recess. The print head positioning mechanism has a configuration in which the mosquito dock member is moved by the moving means and the eccentric shaft is rotated by rotation of the front r lever member.