DE2108006A1 - Mosaic wire print head - Google Patents

Description

WALTHER-BÜROMASCHINEN GMBH GERSTETTEN / WÜRTT.

February 16, 1971 MOSAIC WIRE PRINT HEAD

The invention relates to a mosaic wire print head with therein ■ guided printing needles, which are put together in dots to form an image grid, characters or numbers for printing one writing line and preferably in a 5x7 Image grid built up for upper and lower case letters and the printing pins via individual electromagnets be operated.

In the previously known mosaic wire print heads, the upper and lower case of characters is one from 5x7 Existing image grid points are not easily possible, but a larger image grid must be used, which is composed of at least 5x9 points. Here the necessary 9 grid points, for example, must be set up in the vertical direction, while the 5 grid points in the horizontal direction are sufficient for the display of characters, such as the selected characters according to the print image below point out.

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Practice has now shown that this previously known pressure systems there are a number of disadvantages. For example, there is the need for components to be set relatively very high, which in turn reduces manufacturing costs are adversely affected. Furthermore, the extra weight and the larger dimensions also play a role such a raster print head in connection with the partly additional electronic power control of the Raster print head and the transport and finally the additional effort in the generation of characters as a storage essential role and contributed not insignificantly to the rejection.

Proceeding from this prior art mentioned above, it is therefore the object and purpose of the invention to address these disadvantages to avoid and to propose a mosaic wire print head that can still write letters and special

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Signs of the aforementioned type are permitted on the basis of only 5x7 grid points.

According to the proposed invention, this is achieved in that on guide shafts which are known per se and are arranged parallel to one another with stored on it guided along the print line Transport carriage has the latter mounted in the area of the rear guide shaft bearing eyes, between which parallel to the writing direction and to the guide shafts a further guide shaft is attached, that of the pivotable Storage with temporary lowering of the raster print head is used.

In Figures 1 to 3 of the drawing, the subject matter of the invention is based on a preferred exemplary embodiment,

nes mosaic wire print head, which is shown in the individual ™

is described in more detail below.

Show it:

Figure 1 shows a cross section through the transport carriage with magnet arrangement and view of the raster print head in the normal position,

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FIG. 2 shows a cross section according to FIG. 1 with the raster print head lowered and magnet arrangement in the operative position,

FIG. 3 shows a print image in an enlarged view showing a character with an undersize,

FIG. 4 shows a path-time function diagram according to FIG. 3 of the raster print head during the lowering phase.

According to FIG. 1, the raster print head 2 brings the free ends 3 of the print wires into contact with the ink ribbon 4, whereby this is pressed against the paper 5 to be written on, which in turn with its other side against the writing surface 6 is present. The raster print head is suspended in the transport carriage 7, which is mounted on the guide shafts 8, 9 and is shifted lengthways to the print line. For the purpose of pivoting mounting for the raster print head 2, the transport carriage 7 has two bearing eyes 10, 11 arranged above the rear guide shaft 8, between which parallel to the writing direction and to the guide shafts 8, 9, a further guide shaft 12 is attached and on which the raster print head is pivotably mounted. At the bottom of the raster print head there is also a U-shaped head

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Guide rail 14 arranged on the inner leg surface 15, the contact surface 16 of the transport carriage 7 is additionally supported and this is held down by means of a pressure spring 17 under the influence of, for example, a compression spring. on in this way an air gap 18 is formed between the raster print head and the transport carriage 7. Furthermore is an anchor plate 19 is arranged on the bottom 13 of the raster print head, which is attached to an electromagnet attached to the transport carriage 7 20 faces. For example, the letters Weg should now be written according to FIG. 3 of a print image. According to this, the letter W and e consists of the 5x7 grid points, which do not require lowering of the writing head, while the letter g only with the descender in the same 5x7 grid around the lowering dimension 22 can be written by the writing trunk 21 of the raster print head 2 via a signal coming from a corresponding logic of the electromagnet 20 is actuated and in connection with the anchor plate 19 arranged on the raster print head, the latter is moved around the air gap 18 lowered and the full letter g brought to the print. After the interruption of contact, the between Transport carriage and raster print head attached compression spring 17 of the raster print head returned to the zero position.

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According to FIG. 4, there is the time-distance function of the raster print head 2 at the writing point, from which the lowering time 23 and the return time 24 are shown in an explanatory manner.

The use of upper and lower case letters with descenders according to the proposed invention is not only limited to this, but can also easily be used for thermal printing units, Ink pens, RMP pens, etc. can be used.

Here it is possible, without major structural changes, to lower the raster printing unit in a straight line.

- patent claims -

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Claims (3)

Claims (li mosaic wire print head with printing needles guided in it, which result in characters or digits combined in a picture grid in dots for printing a writing line and preferably built up in a 5x7 picture grid for upper and lower case characters and ^ the print needles are actuated via individual electromagnets, characterized in that bearing eyes (10) are mounted on guide shafts (8, 9), which are known per se and are arranged parallel to one another, with transport carriages (7) mounted on them and guided along the print line, in the area above the rear guide shaft (8) , 11) aufv / eist, between which a further guide shaft (12) is attached parallel to the writing direction and to the guide shafts, which serves as a pivoting bearing for the temporary lowering of the writing trunk (21) of the raster print head (2). 2. mosaic wire print head according to claim 1, characterized in that below the bottom plate (13) of the raster print head (2) a U-shaped guide rail (14) is arranged, on the inner leg surface (15) of which the contact surface is located (16) of the transport carriage (7) and under the 209836/0986 Influence of a compression spring (17) attached between the raster print head and the transport carriage an air gap (18) is formed, which holds the raster print head (2) in the normal basic writing position. 3. mosaic wire print head according to claim 1 and 2, characterized in that one on the one hand on the transport carriage (7) fixed electromagnet (20) and, on the other hand, an opposite one below the base plate (13) Armature plate (19) receives contact closure by a signal coming from the logic. 2 UM «::. , / II 'IM;