JPH0136435B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a type of printing system comprising a rotating continuous type band or type chain and an impact hammer impacting the type and in which printing is effected by a ribbon moving parallel between the paper and the type line.・Related to band printers.

In such type band printers, the distance between the type band and the print hammer should be made as small as possible to shorten the hammer path and achieve high print throughput. Both the printing paper and the ribbon pass through a narrow gap between the type band and the hammer or hammer plate. Since the paper is fed vertically and the ribbon is fed horizontally (meaning there is relative movement between the paper and the ribbon), the ribbon is moved by the paper as the paper or ribbon is transported. There is a risk that this will occur, thus leaving undesirable ink marks on the upper edges of the lines. This dirt on the paper affects the quality of the print.

If the printed document is to be mechanically read by an optical reader, ie if the document is produced by OCR printing, smearing the paper poses a special problem. Ribbon contamination on the paper will generate a text error signal on subsequent machine reading, making the document unsuitable for machine reading.

It is an object of the present invention to provide a type band printer in which even though the gap between the type and the print hammer for the paper and ribbon is fairly small, undesired contact between the paper and the ribbon, i.e. smearing of the paper, does not occur. It is to ensure that.

A type band printer with an ink dispenser between the printing paper and the type is disclosed in German Patent Application No. 20 15 171, in which an impact-resistant foil of synthetic material is provided in the band between the ink dispenser and the type. and this type is stepped either in a direction parallel to or transverse to the print line. However, the purpose of this device is to prevent the type from being soiled by the ink dispenser and to prevent the ink dispenser carbon paper from being punctured by the type. Unwanted contact between paper and ribbon cannot be prevented by this arrangement.

Another device for providing an additional intermediate layer to a type band printer is disclosed in the German Patent Application No. 2003-100002. This patent publication also provides an intermediate band, which moves between the recirculating type band and the platen. Type/belt/
It is known that in printers the type band experiences considerable wear, particularly on the platen as it slides over the platen at high speeds. The aforementioned intermediate band, which is preferably made of flexible metal, is to prevent or reduce this wear.
Therefore, this design is effective only in the type band and platen area and has no effect on paper-ribbon interaction.

However, the arrangement according to the present invention works directly between the paper and the ribbon. According to the invention,
The printing paper is separated from the ribbon throughout, except at the moment of type printing. Therefore, staining of the paper does not occur. The arrangement according to the invention also includes paper and type
This makes it easy to insert the ribbon between the bands. Another advantage of the present invention is that it provides positive braking to the paper so that uniform tension is generated in the paper feed and flapping motion of the paper is eliminated. Another advantage of the present invention is that the separator plate can be easily installed in a type band printer.

The type band printer of FIGS. 1 and 2 consists of a continuous type band 1 made of iron with one track for each type 2 and timing mark 3. The type band 1 moves over a drive roller 4 and a tension roller 5. A synchronous motor 6 is used to drive the type band 1;
This motor acts on the drive roller 4 via a toothed belt, a toothed belt disk 8 and a drive shaft 9.

A platen 10, designed as an elongated block and preferably made of a suitable platen material, such as a non-ferrous metal, is arranged in the type band loop and used to guide the type band 1 and in the print hammer device. It is used as a platen for print hammers 11 arranged on the back side of the printer. Paper 13 moves through the gap between print hammer 11 and type band 1 and is advanced by sprocket wheel 14 in the direction of the arrow. A ribbon 15 is provided between the paper 13 and the type band 1, and this ribbon is attached to a first spool 16 and a second spool.
A reciprocating motion is performed between the spools 17 of the Magnetic sensors 18 control switching of ribbon 15 when each supply spool is nearly empty or when each take-up spool is nearly full. A hammer plate 19 is arranged vertically on the front side of the print hammer device 12 to guide the paper 13. Head 11 of print hammer 11
a, openings 20 in hammer plate 19 permit movement of these heads in the direction of type band 1 and platen 10.

As shown in FIG. 1 and specifically in FIG. 2, frame portion 24 has a separator plate 21 mounted thereon that projects between sheet 13 and ribbon 15. As shown in FIG. As shown in FIGS. 2 and 3, the separator plate 21 has two transverse lines 22a and 22b and an opening 23, which is at the level of the print row and has a length corresponding to the length of this print row. Slightly longer than the row of printed hammers.
The opening 23 therefore provides a passage for the hammer 11 to print the type. Separator plate 2
1, this plate has side arms 21a on both sides. Therefore, the side arm 21a
project on both sides of the print row in the gap between ribbon 15 and paper 13.

Separator plate 21 is suitably secured to frame portion 24, for example by screws (see FIG. 3) or by gluing. The material used for the separator plate 21 is preferably a transparent synthetic foil, for example a polyester foil. The thickness of the separator plate 21 is between 0.2 mm and 0.5 mm, and due to its own elastic action, the separator plate 21 continuously exerts sufficient force on the paper 13 to separate the paper from the ribbon 15 and The thickness is such that the paper is pressed against the hammer plate 19.

Due to the folding lines 22a and 22b, the separator plate 21 has a cross-section in the shape of a flattened Z (see FIG. 2), the lower foot rests smoothly on and is fixed on the frame part 24, and the upper Edge 23
a and the folding line 22b lean against the paper 13 and press it against the hammer plate 19. The greatest effect is obtained when the upper edge 23a of the separator plate 21 is arranged as close as possible to the lower edge of the print row.

FIG. 2A is another design of the hammer plate 19,
The positioning line of the separator plate 21 is then predetermined by the corresponding shape of the hammer plate.
Therefore, the hammer plate 19 has a protrusion 19a directly below the opening 20 on the side facing the separator plate 21. As shown in FIG. 2A, separator plate 2
1 is placed so that its upper edge 23a and folding line 22b rest against the protrusion 19a of the hammer plate 19, so that the tensile action of the sheet 13 is improved.

Next, the operation of the above configuration will be explained.

After inserting the paper 13 into the print processing station and guiding the ribbon 15, the printing process is started and the print hammer 11 is actuated when the respective character of the type band 1 is in its printing position. After one print line has been completely printed, paper 13 is advanced one step in the direction of the arrow through sprocket wheel 14 and placed on the next print line. During this progress time,
The brake bar 25 (see FIG. 2), which presses the sheet against the hammer plate 19, is released so that the sheet 13 is transported without any braking action;
For example, it is released electromagnetically against a spring force.

In the gap between the type band 1 and the hammer plate 19, the ribbon 15 tends to rub against this paper 13 during the relative movement of the paper 13 and the ribbon 15, thus covering the paper surface which should still be blank. becomes dirty. However, the separator plate presses the sheet 13 away from the ribbon 13 against the hammer plate 19 in the area of the ribbon 15 and thus in the edge area on both sides of the print line due to the side arms 21a between the sheet 13 and the ribbon 15. The ribbon and paper are separated in the print line and the entire area of the ribbon 15. As a result,
The paper 13 is no longer stained by the ribbon 15. Another effect is that the separator plate 21 assists the action of the brake bar 25 and provides a positive paper tensioning action since the separator plate rests over the paper 13 against the hammer plate 19 throughout. In particular, this tensile method has been applied to the design of FIG. 2A. In this way, paper transport is stabilized and the printing process can be performed effectively.

[Brief explanation of drawings]

Figure 1 is a perspective view of a type band printer showing the basic assembly and parts associated with the separator plate between the ink ribbon and paper;
The diagram shows plane 2 of the type band printer in Figure 1.
2A is a partial sectional view of FIG. 2 showing an alternative design of the hammer plate, and FIG. 3 is a view showing a separator plate between the ink ribbon and the paper. 1...Type band, 15...Ribbon, 10
... platen, 13 ... paper, 21 ... separator plate, 11 ... print hammer, 25 ... brake bar, 19 ... hammer plate.

Claims (1)

[Claims] 1. A ribbon that is fed in the direction of the print line is placed between the print paper that is fed in the direction perpendicular to the print line and the type band that moves in the direction of the print line. In a type band printer that prints characters by arranging the ribbon, a hammer plate is provided on the side opposite to the type band with respect to the ribbon and has an opening at a position corresponding to the type of the type band; the printing paper is disposed between the plate and the ribbon; and a hammer head for driving the printing paper and ribbon through the opening in the hammer plate toward the type band for printing. , an elastic separator plate disposed between the printing paper and the ribbon, the separator plate having a pair of side arms projecting upward from both ends thereof, and a pair of side arms projecting upward from both ends of the separator plate; It is located between the arms and has an upper edge adjacent to the print line printing area, and is formed to provide an opening in the print line printing area, and its elastic action allows the printing paper to be spread over almost the entire width of the paper. A type band printer, characterized in that the printing paper acts to separate the printing paper from the ribbon by pressing against the hammer plate over a period of time.