JPH0262274A - Structure of printing element of passbook printer - Google Patents

Abstract

PURPOSE:To dispense with a plate-shaped guide and a mask, to facilitate thereby adjustment and to make it possible to follow a thick medium smoothly by fitting a barrel-shaped guide roller in a sphere of prescribed dimensions on both front and rear sides of a printing head. CONSTITUTION:A passbook 15 being held on a platen 12, a pair of guide rollers 17 are fitted on both front and rear sides in the direction of advance of a printing head 11 and are made integral with the printing head 11. Each of the guide rollers 17 is shaped in a barrel having a tapered part 17a and a cylindrical part 17b. On the occasion of putting-in and putting-out, the passbook 15 is conveyed in the axial direction of the guide rollers 17 and a stepped part in the end of the passbook can clear the rollers smoothly due to the operation of the tapered part 17a.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of the printing section of a bankbook printer, the purpose of the present invention is to provide a print head structure that can smoothly follow thick media and is easy to adjust. The print head includes a head and a platen facing the print head, and a head pin built into the print head allows a desired ink ribbon to be applied onto the medium supported on the platen via an ink ribbon supported so as to bridge the tip of the print head. A printing unit of a passbook printer configured to print,
On the front and back sides of the print head in the direction of print head movement,
A pair of guide rollers is provided integrally with the print head at a position lower than the print head by a predetermined height, and the guide rollers are configured to have a barrel shape with tapered portions at both ends.

[Industrial application field]

TECHNICAL FIELD The present invention relates to an improvement in the printing section of a passbook printer.

[Conventional technology]

As shown in FIG. 5, the printing section of a dot printer consists of a print head 1 and a platen 2. When no medium is present, the print head 1 and the metal platen 2 are connected to each other.
A gap of approximately 0.51 m is maintained between the two. When the medium 5 to be printed is held on the platen 2, either the print head or the platen is displaced up and down to establish a predetermined distance between the print head 1 and the medium 5. The printer is configured to perform predetermined printing on a medium via an ink ribbon 3 held so as to bridge the tip of the print head 1, using a large number of hard disk bins 4 built into the print head. To prevent the ink ribbon 3 from hanging down and contaminating the medium 5 during printing, a mask 6 is provided with an opening only in the area where the head bin 4 enters and exits, as shown in FIG.
is provided at the tip of the print head 1 and holds the ink ribbon 3.

For passbook printers that print on bank passbooks, the target medium (passbook) is considerably thicker than normal cut sheets or continuous forms, and has a folded part called a center hold in the center. Therefore, a pair of inclined left and right guides 7 integral with the mask 6 are provided so that the print head can smoothly overcome these steps when moving to the print area of the medium. That is, the print head is configured to cross the step along the guide 7 and to maintain a constant distance from the medium at all times.

[Problem to be solved by the invention]

However, in this passbook printer, it is difficult to maintain parallelism by maintaining the same distance a between the lower surface of the mask 6 and the surface of the platen 2 on both sides, and it is also difficult to maintain parallelism between the tip of the print head 1 and the surface of the platen 2. Adjusting the spacing is also troublesome. Furthermore, there is a drawback that alignment of the head bin 4 with respect to the diamond-shaped opening of the mask 6 requires time and effort.

An object of the present invention is to solve the problems of the prior art caused by the existence of such a mask, and to provide a print head structure that can smoothly follow thick media and is easily adjustable. do.

[Means to solve the problem]

This purpose includes a print head and a platen facing the print head, and is supported on the platen by a head bin built into the print head via an ink ribbon supported so as to bridge the tip of the print head. A printing unit of a passbook printer configured to perform desired printing on a printed medium, the position being lower than the print head by a predetermined height on the front and rear sides of the print head in the direction of movement of the print head. This is achieved by a structure of the printing section characterized in that a pair of guide rollers is provided integrally with the printing section, and the guide rollers are barrel-shaped with tapered sections at both ends.

[Effect]

The guide roller is integrally attached to the print head, and when the print head moves, it can smoothly move over the platen or the medium, and can smoothly overcome steps with different thicknesses. Since the guide roller is provided with tapered portions at both ends, it can easily overcome the stepped portion of the medium even when moving perpendicular to the printing direction when sucking and discharging the passbook to the printing position.

As a result, it is possible to prevent an accident in which the print head gets caught on the medium, and a predetermined distance is always maintained between the tip of the print head and the surface of the medium, resulting in high quality printing. Further, since the mask which is essential in the conventional mechanism can be omitted, adjustment becomes very simple.

Hereinafter, the present invention will be explained in more detail based on preferred embodiments shown in the drawings.

〔Example〕

FIG. 1 is a perspective view showing the configuration of a printing section of a passbook printer according to the present invention.

The passbook 15 unfolded into a double-page spread is held with the area to be printed lying on the platen 12. The print head 11 performs desired printing while moving along this platen 12.

A pair of guide rollers 17 are attached to the front and back sides of the printing lid 11 in the direction of movement (indicated by the arrow), and are integrated with the printing head 11. This guide roller 17 corresponds to the guide 7 in the prior art, and is used to smoothly get over the stepped portion of the passbook.

As shown in FIG. 2, the guide roller 17 has a so-called barrel shape having tapered portions 17a at both ends and a cylindrical portion 17b at the center. The reason for this shape will be explained in detail later.

As shown in FIG. 3, the guide roller 17 is installed in the vertical direction (Z-axis direction in FIG. 1) at a position such that the distance between the bankbook 15 and the tip of the print head 11 is 0.4 to 0.4 mm as before. 5 m
It is desirable that the setting is maintained at a certain level.

Furthermore, as shown in FIG. 4, the mounting position of the guide roller 17 in the front-rear direction (Y-axis direction) is such that the portion of the guide roller 17 that moves along the medium surface interferes with the print area of the print head 11, resulting in printing problems. It is desirable that the head pin 14 be removed further forward than the frontmost head pin 14 so as not to contaminate the characters that have just been written.

Furthermore, when the passbook 15 moves by a predetermined amount in the direction perpendicular to the printing direction during a line feed operation and new printing is started, the cylindrical portion 17b of the guide roller 17 is positioned within the blank space between the printing lines. It is desirable that the length of this cylindrical portion 17b is set as short as possible (for example, about 1.2 + n) so that the cylindrical portion 17b can be easily inserted.

When the passbook is sucked in and discharged before and after printing on the passbook, the passbook 15 is conveyed in a direction perpendicular to the printing direction of the print head 11, that is, in the axial direction of the guide roller 17. The center hold and the stepped part at the end are
It will be easily understood that the action of the tapered portion 17a of the guide roller 17 allows for smooth overcoming.

〔Effect of the invention〕

As described in detail above, according to the present invention, by installing barrel-shaped guide rollers in a predetermined dimensional range on both the front and rear sides of the print head, it is possible to achieve the same level difference without using the conventional plate-shaped guide. You can get the effect of overcoming it. Furthermore, since it is now possible to omit the mask, which has traditionally been a problem due to its troublesome adjustment, assembly and maintenance of the device is facilitated, and stable printing can be ensured.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a printing unit equipped with a guide roller of the present invention, Fig. 2 is a side view showing each part of the guide roller, and Fig. 3 is a front view showing the positional relationship of the guide roller with respect to the print head. , FIG. 4 is a side view, FIG. 5 is a front view of a conventional printing unit equipped with a tapered guide plate, and FIG. 6 is a plan view showing the opening of the mask. 1.11--Print head, 2.12--Platen, 3--Ink ribbon, 4.14--Head pin, 5.15--Medium 1 passbook, 6--Mask, 7- Guide .

Claims (1)

[Claims] 1. Print head (11) and platen (1) facing it
2), and the ink ribbon (3) is supported by a head pin (14) built into the print head (11) so as to bridge the tip of the print head (11), and the platen (12) is ) supported on the medium (15)
A printing unit of a passbook printer configured to perform desired printing on the print head (11).
), a pair of guide rollers (17) are provided integrally with the guide rollers (17) at a predetermined height lower than the guide rollers (17).
7) is a structure of a printing part characterized by forming a barrel shape having tapered parts (17a) at both ends.