JPH0764054B2 - Printer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer, and more particularly, to an impact type printer having a type wheel on which a plurality of characters are arranged and performing a printing operation via a striking mechanism.

[Prior Art] In an impact type printer of this type, a type wheel on which a plurality of types are arranged is rotated around a rotation axis,
Printing is performed by guiding a print character to be printed to a print position and hitting the print character with a hammer. FIG. 3 shows a type wheel of such a printer, which is a so-called daisy type wheel. The type wheel 1 has a spoke portion 1A formed by radially projecting from a central disc portion 1B. A type portion 2 is integrally formed at the tip of the spoke portion 1A. Here, the type wheel 1 is rotatably fixed to the rotary shaft 6 as shown in FIG. 4, and when the type part 2 to be printed is rotated to a position where it reaches the front surface of the printing hammer 11. Stop the printing wheel 1 and hammer
Printing is performed on the printing paper 9 on the platen 3 via the ink ribbon 10 by the striking operation of 11A.

By the way, depending on the type, there may be special characters such as Hangul, Thai, etc. depending on the type of characters formed in the character part 2 of the character wheel 1. There is a type in which the center of the type is deviated from the center line of the spoke portion 1A when the type wheel 1 is stopped.

FIGS. 5 (A), (B) and (C) show an example in which such characters are provided in the character part 2, and in the character part 2 which is the tip of the spoke part 1A, the collision of the print hammer 11 is shown. A type pedestal 14 is provided on the spoke pedestal 12 to be struck for the purpose of reinforcing the type 13, and the type 13 is mounted on the type pedestal 14. In this example, the center line of the type 13 is attached. X ₂ is displaced to the left from the center line X ₁ of the spoke portion 1A.

Therefore, when the case where printing is performed by such a type portion 2 is shown, since the center of the hammer shaft 11A and the center line of the spoke portion 1A coincide with each other as shown in FIG. 6, the type 13 and its type pedestal are aligned. All of 14 and the like are driven toward the print sheet 9 while being displaced from the spoke center line X ₁ .

For this reason, when the leftmost end and the rightmost end of this type 13 are represented by A and B, respectively, the rightmost end B closer to the spoke center line X ₁ has a contact pressure more than the leftmost end A. Is larger and the surface of the platen 3 is made of an elastic material, the obtained print has a portion C corresponding to the leftmost end portion A as shown in FIG. 7, for example.
Is faint.

Although not shown in the figure, on the contrary, not only does the printing quality deteriorate in any case due to excessive ink deposition on the printed portion corresponding to the rightmost end portion B, which causes bleeding. There is a drawback in that the wear is promoted by one-sided contact.

[Object] The present invention has been made in view of the above-mentioned drawbacks, and normal printing can be obtained even for a typeface in which the centerline of the typeface is displaced to the left or right with respect to the centerline of the spoke due to the difference in the typeface and language. The
An object of the present invention is to provide a printer capable of preventing deterioration of printing quality and improving durability of a printed portion.

[Summary of the Invention] In order to achieve the above object, the present invention includes a type wheel having a type provided on a spoke base at the end of an elastic spoke and a print hammer, and a center line of the spoke and a center of the print hammer. In the printer in which printing is performed by hitting the rear surface of the spoke pedestal with the printing hammer, the spoke pedestal that carries the type of the character eccentric to the left or right with respect to the center line of the spoke It is characterized in that the distance between the back surface and the surface on the printing side of the type is gradually reduced from the end side of the spoke pedestal that is farther from the center line of the spoke toward the other end side.

Embodiments Embodiments of the present invention will be described in detail and specifically below with reference to the drawings.

1 (A), (B) and (C) show an example of a character portion of a daisy type character wheel according to the present invention. here,
13 is a typeface similar to that shown in FIGS. 5A to 5C, in which the center line, that is, the vertical centerline passing through the left and right centers of the typeface is shifted to the left or right. Is an example.

Therefore, in this example, in forming the spoke pedestal 22 in the type portion 20, the striking surface 22A is inclined in the left-right direction.
In the case where the center line X _{2 of} is displaced to the left, the pedestal 22 is inclined so that the thickness thereof gradually decreases from the left end to the right end,
A gradient of Δd is provided between them.

A state in which a character is formed by the character portion 20 configured as described above will be described with reference to FIG. 2. When the tip of the hammer shaft 11A comes into contact with the striking surface 22A of the spoke pedestal 22 as shown in FIG. A pressing force is applied to the D portion of the striking surface 22A.

Thus, the type portion A on the side closer to the portion D on which the pressing force acts first comes into contact with the paper surface, but the surface of the platen 3 has elasticity, and the spokes 1A themselves also have elasticity. At the next moment, the portion E on the striking surface 22A also comes into contact with the tip of the hammer shaft 11A, and the pressing force is transmitted to the character portion B through this operation.

As described above, in the type part according to the present invention, the pressing force by the impact is input from the side where the center line of the type is deviated, and the pressing force is distributed to the part where the pressing force is hard to be input. As a result of consideration, even in the case of printed characters as shown in FIG. 7, for example, high-quality printing with uniform printing density is obtained, and lightening does not occur in the portion C.

The gradient Δd of the slope formed on the rear surface 22A of the sports pedestal
It is needless to say that the above should be set in accordance with the type of type, that is, the deviation of the center as described above, in consideration of the hammer impact pressure and the elasticity of the surface having the platen 3. However, the present invention is not limited to any value of Δd.

[Effects] As described above, according to the present invention, a type wheel having a type on the spoke pedestal at the tip of the spoke and a printing hammer are provided, and the center line of the spoke is aligned with the center of the printing hammer. In the printer in which printing is performed by hitting the back surface of the spoke pedestal with the printing hammer, the back surface of the spoke pedestal that carries the type of a character eccentric to the left or right with respect to the center line of the spoke. Since the distance from the side of the printed side of the type is gradually reduced from the end side of the spoke pedestal farthest from the center line of the spoke toward the other end side, in the conventional case, the center line of the spoke. On the other hand, when printing a type of character that is eccentric to the left or right, the contact pressure on the end side near the spoke center line becomes larger than the contact pressure on the other end side on the spoke base. Therefore, it is possible to solve the problem that the print density is changed and the print quality is degraded. That is, when printing the characters of the typeface as described above with the simple configuration as described above by hitting the back surface of the pedestal with a printing hammer, the spoke pedestal is caused to rotate around the spoke center line through the elastic spokes, By contacting the printing paper with the end of the printing type that is farther from the center line of the spoke first, the contact pressure generated between the left and right edges of the printing and the printing paper can be made almost uniform, resulting in uniform printing. High-quality printing with high density can be obtained, and the life of the printed characters can be extended.

[Brief description of drawings]

FIGS. 1 (A), (B) and (C) respectively show a front view, a side view and a top view of an example of a character portion of a character wheel according to the printer of the present invention, and FIG. 2 is printed by the character portion. FIG. 3 is a front view showing an example of a conventional type wheel, FIG. 4 is a configuration diagram showing an example of a main part relating to printing of a conventional printer having a type wheel, FIG. FIGS. (A), (B) and (C) are front views, side views and top views, respectively, showing an example of the print part, and FIG. 6 is a diagram schematically showing a state in which printing is made by the print part. FIG. 7 is an explanatory diagram related to printing of an eccentric character made by the character portion. 1 ... Type wheel, 1A ... Spoke section, 1B ... Disk section, 2,20 ... Type section, 3 ... Platen, 6 ... Rotation axis, 9 ... Printing paper, 10 ... Ink ribbon, 11 ...... Printing hammer, 11A …… Hammer axis, 12,22 …… Spoke pedestal, 22A …… Impacting surface, 13 …… Type, 14 …… Type pedestal.

Claims (1)

[Claims] 1. A printing wheel having a type wheel provided with a type on a spoke pedestal at the tip of an elastic spoke, and a printing hammer, wherein the center line of the spoke is aligned with the center of the printing hammer, and the back surface of the spoke pedestal is printed. In a printer in which printing is performed by hitting with a hammer, a gap between the rear surface of the spoke pedestal that carries the type of a character eccentric to the left or right with respect to the center line of the spoke and the surface on the print side of the character. Is gradually reduced from the end side of the spoke pedestal, which is farther from the center line of the spoke, toward the other end side.