JP3105127B2 - Ribbon protector mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ribbon protector mechanism used for a printing section in a serial dot impact printer.

[0002]

2. Description of the Related Art Conventionally, in a serial dot impact printer, a ribbon protector mechanism used in a printing section guides a sheet between a platen and a ribbon protector, and transfers ink between the ribbon protector and the print head section. Some guide the ribbon. The procedure for mounting the ribbon protector in the printing unit when assembling such a printer will be described below.

First, a head gap, which is a gap between a platen and a tip of a head nose of a print head mounted on a carriage, is adjusted. Next, the ribbon protector is screwed to the carriage. At this time, the paper root gap, which is the gap between the platen and the ribbon protector,
Adjust the ribbon root gap, which is the gap between the ribbon protector and the tip of the print head nose. By this adjustment, a paper root gap in which the paper is accurately fed and a ribbon root gap in which the ink ribbon travels accurately are secured.

[0004]

In the conventional ribbon protector mechanism, when the ribbon protector is screwed to the carriage, the paper root gap and the ribbon root gap are finely adjusted while being measured with a gauge or the like, and the ribbon protector is finely adjusted. Since the protector must be secured so as not to be distorted by screwing, a person skilled in this operation must perform the operation, and the operation takes time and the workability is poor.

[0005]

Means for Solving the Problems In order to solve the above problems, a solution provided by the present invention is that a print head mounted on a carriage frame faces a platen via a ribbon protector provided on the carriage frame. Provided in the ribbon protector mechanism that feeds the paper between the ribbon protector and the platen and causes the ink ribbon to travel between the ribbon protector and the print head. A length that is provided on the carriage frame so as to be movable between the print head and a ribbon root gap at which the ink ribbon can accurately travel at a position sandwiching the head nose of the print head from both sides. With the carriage frame protruding toward the ribbon protector by that amount, The ribbon protector is in contact with the ribbon protector when the ribbon protector moves toward the print head, and the ribbon protector is positioned at a position equal to or greater than a position at which a ribbon root gap capable of accurately moving the ink ribbon can be secured. A convex portion for restricting movement to the side is provided.

[0006]

According to the present invention having the above-described structure, the ribbon protector is provided on the carriage frame so as to be movable between the platen and the print head. Distortion can be prevented. When the leading end of the sheet wound around the platen comes into contact with the ribbon protector, the leading end of the sheet pushes the ribbon protector and moves the ribbon protector toward the print head.
As a result, a paper route gap for accurately feeding the paper is secured. Note that when the ribbon protector moves to the print head side, even if the ribbon protector tries to move to the print head side beyond the position where a ribbon root gap that allows the ink ribbon to run accurately can be secured, the ribbon protector hits the convex part. In contact, further movement is regulated. This ensures a ribbon root gap in which the ink ribbon travels accurately. Therefore, even if the ribbon protector can be freely moved between the platen and the print head, it is possible to secure a paper route gap for feeding the paper accurately, and to set a ribbon route gap for the ink ribbon to travel accurately. Can be secured.

[0007]

An embodiment of the present invention will be described with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals. FIG. 1 is a perspective view showing one embodiment of the present invention, and FIG. 2 is a cross-sectional view seen from the direction of arrow A in FIG.

The present embodiment differs from the prior art in that the ribbon protector is freely movable between the platen and the ribbon guide. In FIG. 1, a printing unit 1
Is composed of a print head 2 for printing by projecting a wire from a tip, a carriage frame 3 on which the print head 2 is mounted, and the like. The carriage frame 3 is attached to a guide shaft 5 provided in parallel with the platen 4 by arrows CC.
It is slidably mounted in the 'direction. The platen 4 is attached to a side frame (not shown) so as to be rotatable in the direction of the arrow DD ′.

A ribbon guide 6 is mounted on the carriage frame 3. The ribbon guide 6 includes a leading end guide 6 a surrounding the head nose 2 a of the print head 2,
Guides 6b and 6c provided on both sides of the distal end guide portion 6a
It is composed of Posts 7a, 7b, links 8a, 8b
The ribbon shift mechanism constituted by moving the ribbon guide 6 in the direction of the arrow EE 'to position a desired color ink ribbon at the tip of the head nose 2a.

[0010] Between the ribbon guide 6 and the platen 4,
A ribbon protector 9 is provided to prevent the paper from coming into contact with the ink ribbon and becoming dirty. The ribbon protector 9 includes a shoulder screw 10 on the carriage frame 3.
As a result, it is movably locked in the direction of arrow FF ′.

In FIG. 2, the position where the shoulder screws 10a and 10b of the ribbon protector 9 are attached is
Elongated holes 13a and 13b are provided. This long hole 13
The shoulder screws 10a and 10b fixed to the carriage frame 3 are loosely fitted to the a and 13b, respectively.

Also, the contact portions 9a of the ribbon protector 9
Protrusions 6d and 6e of guides 6b and 6c are provided at positions facing 9b, respectively. These protrusions 6d, 6e
Are contact portions 9a and 9b of the ribbon protector 9, respectively.
The ink ribbon 11 protrudes from the carriage frame 3 by a length that secures a ribbon root gap that allows the ink ribbon 11 to travel sufficiently accurately when it comes into contact with the carriage frame 3.

The ink ribbon 11 is provided on the side 6 of the guide 6b.
f, travels in the direction of arrows GG 'while being guided by contacting the side portions 6g of the distal end guide portion 6a and the guide 6c. At a position facing the head nose 2a of the ribbon protector 9, a protector film 12 is fixed. The print head 2 performs printing on the paper wound around the platen 4 via the ink ribbon 11 and the protector film 12.

The operation of adjusting the gap of the printing unit 1 as described above will be described. FIG. 3 is a sectional view taken along arrow BB in FIG. First, the head gap, which is the gap between the platen 4 and the tip of the head nose 2a, is adjusted. Next, the shoulder screw 10b is loosely fitted in the long hole 13b of the ribbon protector 9, is fixed to the carriage frame 3, and the ribbon protector 9 is attached between the ribbon guide 6 and the platen 4. This prevents distortion of the ribbon protector due to screwing as in the related art.

When the paper 14 is wound around the platen 4 in the direction of arrow H and fed, the leading end 14a of the paper 14 strikes the ribbon protector 9. The ribbon protector 9 is pushed by the tip end 14a and moves in the direction of arrow F. As a result, a paper route gap where the paper 14 is accurately fed is secured. Further, even if the ribbon protector 9 moves in the direction of arrow F, further movement is restricted by the contact portion 9b of the ribbon protector 9 contacting the convex portion 6e of the guide 6c. Therefore, a ribbon root gap in which the ink ribbon travels accurately is secured.

[0016]

Since the present invention is configured as described above, it has the following effects.

That is, the ribbon protector is provided on the carriage frame so as to be movable between the platen and the print head, and the ink ribbon moves accurately at a position sandwiching the head nose of the print head from both sides. The ribbon protector is provided on the carriage frame so as to protrude toward the ribbon protector by an amount corresponding to the obtained ribbon root gap. When the ribbon protector moves toward the print head, the ribbon protector comes into contact with the ribbon protector, and By providing a convex portion that restricts the ribbon protector from moving to the print head side above a position where a ribbon root gap that allows the ribbon to run accurately can be prevented from distorting the ribbon protector due to screwing. , Paper root gap and ribbon root gap, who It is possible to easily secure, it is possible to prevent the variation of adjustment by the operator. As a result, the quality of the printer can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention.

FIG. 2 is a cross-sectional view as viewed from the direction of arrow A in FIG.

FIG. 3 is a sectional view taken along a line BB in FIG. 2;

[Explanation of symbols]

 2 Print head 4 Platen 6 Ribbon guide 9 Ribbon protector 11 Ink ribbon 14 Paper

Claims (1)

(57) [Claims] A print head mounted on a carriage frame is provided to face a platen via a ribbon protector provided on the carriage frame, and feeds paper between the ribbon protector and the platen. ,
In a ribbon protector mechanism for running an ink ribbon between the ribbon protector and the print head, the ribbon protector is provided on the carriage frame so as to be movable between the platen and the print head. At the position sandwiching the head nose of the print head from both sides,
The ink ribbon is provided on the carriage frame so as to protrude in the direction of the ribbon protector by a length for securing a ribbon root gap capable of accurately traveling, and is provided when the ribbon protector moves to the print head side. A ribbon provided in contact with a ribbon protector and provided with a convex portion for restricting movement of the ribbon protector toward the print head at a position equal to or higher than a position at which a ribbon root gap allowing the ink ribbon to travel accurately can be secured. Protector mechanism.