JPH0428779Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to an improvement in the structure of a printing device such as a dot printer.

(b) Technical background FIG. 1 is a schematic explanatory diagram of a conventional printing device.

FIG. 1 shows a type of printing device in which recording paper is pushed into a printing section. In the figure, 1 is a housing, 2 is a print head, 3 is a paper feed platen, and 4 is a recording paper stacked with carbon paper sandwiched between them, or so-called non-carbon paper stacked on top of each other. 5 is a tractor for conveying the copy paper 4;
1 is a paper guide, and 7 is a bail roller which guides and discharges the copy paper 4 after printing to the outside of the housing 1 by coming into contact with the platen 3. Further, the copy paper 4 is made of two or more sheets stacked one on top of the other, and is stacked by bending the protrusions that protrude alternately at the edges of the paper, and is further provided with perforations that can be cut into a predetermined size. ing.

In the above-mentioned configuration, the print head 2 is reciprocated along the axial direction of the platen by a carrier (not shown), and at the same time, the wire pin (not shown) of the print head 2 is driven based on information from the host device, thereby printing the copy paper. 4 and an ink ribbon (not shown) is struck to print on the copy paper 4.
Every time one line of printing is completed, the tractor 5 and platen 3 are driven to change the copy paper 4.

At this time, the copy paper 4 is quite thick because the recording sheets of the copy sheets are stacked on top of each other, and when it is conveyed by the cylindrical platen 3,
There is a difference in paper feed amount between printing paper and copy paper.

That is, as shown in FIG. 2, the outer paper and the inner paper have different circumferential diameters, so there is a difference in paper feeding speed between the two.

Due to this paper feeding speed difference, the inner paper is not fed, and the inner and outer paper sheets are misaligned between the tractor 5 and the paper feeding platen 3, resulting in a paper jam. Further, when printing on a slip or the like on which a predetermined format is printed, printing misalignment occurs.

This becomes more noticeable as the wrapping angle θ of the copy paper 4 around the platen 3 becomes larger.

For this reason, as shown in FIG. 3, another tractor 5 is provided, and the transport path of the copy paper 4 in the portion of the platen 3 facing the print head 1 is kept in a nearly straight line, that is, the wrapping angle around the platen 3 is adjusted. By creating a state in which θ is small, the difference in feeding speed between the inner and outer sheets is reduced, and paper misalignment is eliminated.

However, since the copy paper after printing is normally discharged to the rear of the housing 1 of the printing device, it is necessary to bend the copy paper backward by the guide 8.

Therefore, since the copy paper 4 is bent at the bending portion 8a of the guide guide 8, a speed difference occurs between the inner and outer sheets at this portion, and the guide guide 8
The paper on the inside (the side that contacts the guide 8) becomes slack at the bent portion 8a. As the copy paper 4 is conveyed, since the guide 8 is a flat plate, the slack gradually grows and reaches the bail roller 7, causing a jam in the printing section.

Furthermore, even if a jam does not occur in the printing section, since the guide 8 is a flat plate, the sagging portion is squeezed at the folded portion 8a, where there is no place to escape, and the sagging portion is squeezed at the perforation of the paper. The disadvantage was that the paper inside was folded.

(c) Prior Art and Problems In order to prevent the paper from folding as described above, the applicant has proposed a printing device as shown in FIGS. 4 and 5.

FIG. 4 is a diagram for explaining the previously proposed printing device.

The difference between the figure and FIG. 3 is that a recess 10 is provided in the guide 9. With the configuration shown in FIG. 4, even if the copy paper 4 is folded and conveyed at the folded part 9a of the guide 9, the inner paper 4' generated at the folded part 9a Since the slack of the paper 4' can be absorbed by the concave portion 10, the slack of the paper 4' does not get into the bail roller 7 due to growth, and it is possible to prevent the occurrence of paper jam and also to prevent misalignment of printing.

In addition, since the recess 10 provides a sufficient escape area for the copy paper 4', the rigidity of the inner copy paper 4 can be maintained sufficiently high, so that when the copy paper 4 is conveyed as printing progresses, the paper The engagement of the perforations and the protrusions on the side edges pushes up and conveys the outer paper at the folded portion 9a of the guide guide 9, thereby preventing the paper from folding in the vicinity of the perforations.

The guide 9 is shaped like an inverted dogleg, but since the paper 4 has sufficient rigidity, the leading edge of the paper moves along the guide 9 when printing starts, and the upper When it comes into contact with the guide 11, it is bent and transported.

FIG. 5 shows a modification of the printing device shown in FIG.

The difference between the figure and FIG. 4 is that the upper guide 12 is rotatably supported around a shaft 13 in the direction of the arrow shown by symbol A in the figure, and the lower part is brought into contact with the platen 3 during rotation. copy paper 4
The reason is that the cutter 12a is capable of cutting.

By adopting the configuration as shown in the figure, in the state shown in FIG. 5a, the copy paper 4 is guided until it reaches the folded part 9a at the tip of the guide 9, and in the state shown in FIG. 5b. cutter 12a as shown
The copy paper 4 can be cut after printing is completed.

Incidentally, the cutting is performed by the operator pulling down the upper part of the guide 12 toward the print head 2 side.

Further, in FIG. 5a, the guide 12 is fixed by a fixing device (not shown), which is released at the time of cutting.

Here, in the conventional printing device mentioned above,
Since the outlet for discharging the copy paper 4 from the housing 1 is an opening, it has the drawback of generating noise. It is possible to cover the printing section with a soundproof cover to prevent the generation of noise, but for example, as shown in Figure 5, it is possible to use the tip of the guide at the top of the printing section as a cutter for cutting the paper. In a rotatably supported device, if the soundproof cover 14 is disposed near the guide 12, it will not be able to rotate. Also, in order to make it rotatable, the soundproof cover 1
4, a gap must be provided between the two, and the problem is that it is not possible to prevent the generation of noise.

(d) Purpose of the invention The purpose of the invention is to:
To provide a printing device capable of suppressing as much as possible the generation of noise generated from a discharge port through which copy paper or the like is discharged from a casing even when a guide having a cutter at the tip is provided in the upper part of a printing section.

(e) Structure of the invention The object is to include a printing means for printing on a recording medium, a cover that covers the printing means from the front of the device, and a cover that is rotatably supported on a fulcrum and that extends above the tip and above the device. A guide for guiding the recording medium to be ejected is provided with a cutter portion having a cutter for cutting the recording medium by contacting the platen below the tip thereof, and when cutting the recording medium, the guide guide is directed toward the cover. In the printing device in which the cutter part is rotated in a direction in which the cutter part is rotated, the cutter part is provided with a protrusion part configured to close a gap between the cover part and the cutter part when the printing means is operated. This is achieved by providing a printing device with the following characteristics.

(f) Embodiments of the invention Hereinafter, embodiments of the printing device according to the invention will be described in detail with reference to the drawings.

FIG. 6 is a diagram for explaining an embodiment of the printing device according to the present invention.

In the figure, reference numeral 15 denotes a protrusion provided on the guide 12 for guiding the copy paper 4, and the tip 15a thereof is provided so as to be substantially in contact with the cover 14 in the paper guide state shown in FIG.

With this configuration, it is possible to suppress leakage of noise generated by a wire pin (not shown) of the print head 2 hitting the platen 3 from the copy paper 4 outlet.

Furthermore, as shown in FIG. b, the copy paper 4 is cut by
This is done by rotating the guide 12 in the direction of arrow B.

(f) Effects of the invention As explained above, according to the invention, it is possible to prevent the generation of noise even in a printing device having a guide having a cutter at the tip above the printing section.

[Brief explanation of drawings]

1 to 5 are diagrams for explaining a conventional printing device, and FIG. 6 is a diagram for explaining an embodiment of the printing device according to the present invention. In the figure, 2 is a print head, 3 is a paper feed platen, 4 is a sheet of paper, 5 is a tractor, 7 is a bail roller, 9, 11, 12 are guides, 9a is a folded part, 10 is a recessed part, 12a is a cutter , 14 is a soundproof cover, and 15 is a protrusion.

Claims (1)

[Claims for Utility Model Registration] Printing means for printing on a recording medium, a cover that covers the printing means from the front of the device, and a record rotatably supported on a fulcrum and discharged above the leading end and above the device. A guide for guiding the medium is provided with a cutter portion having a cutter for cutting the recording medium by contacting the platen below the tip thereof, and when cutting the recording medium, the guide guide is provided with a cutter portion having a cutter for cutting the recording medium by contacting the platen, and when cutting the recording medium, the guide guide is provided with a cutter portion having a cutter for cutting the recording medium by contacting the platen. A printing device in which a cutter part is rotated, characterized in that the cutter part is provided with a protrusion configured to close a gap between the cover part and the cutter part when the printing means is operated. Device.