DE2248564A1 - PRINT HEAD FOR MOSAIC SERIAL PRINTER - Google Patents

Description

Patent attorney
Dipl.-Phys. Leo Thul
Stuttgart

T.J. Holland 2

INTERNATIONAL STANDARD ELECTRIC CORPORATION, New York

State of the art print head for mosaic serial printer

In the case of fast-working serial printing units, it is extraordinary It is important that the car equipment is as light as possible in order to provide the required acceleration at the beginning of the line to keep within reasonable limits and to keep the carriage return to the beginning of the line in most cases very short time available with certainty.

In the case of mosaic serial printers, this problem occurs primarily due to the bulk print wire drives. For this Basically, one has already gone over to only printing heads with a column-oriented row of in these printing units To use printing needles which, guided along the line, put together the characters to be printed one after the other in columns. This measure makes it possible to achieve a considerable reduction in the moving mass. At high However, this is not enough for writing speeds.

task

The invention specified in the claim is therefore the task based on an extremely light print head for mosaic serial printers to accomplish.

advantages

The advantages achieved by the invention according to the claim are in particular that the print needle drives

21.y.1972

vHy / sch · ./.

309815/0860

T.J. Holland 2 - 2 -

2748564

Reduced to half the number previously required can, which allows a reduction in the mass to be moved by almost half without thereby affecting the Writing speed experiences a major limitation.

Description of the invention

On the basis of an exemplary embodiment, the invention is connected explained in more detail below with the drawing.

The schematic drawing represents a along the pressure cell Slidable printing element of a mosaic printing unit for serial reception of characters. A series of vertically oriented Writing head 1 carrying printing needles 3 is fixedly arranged on a carriage device 2. This is common and therefore not shown in more detail, mounted displaceably transversely to a sheet or web-shaped recording medium. The direction of movement of the carriage device 2 during printing is marked by the arrow A. At the beginning of a In the new line, the carriage device 2 returns in a retrograde direction to the line start position. The imprint of a character takes place in such a way that during the lateral displacement of the carriage device 2 in Line direction, the printing needles 3 are selectively brought to print and thereby a character to be displayed A corresponding point grid or mosaic is formed as a rectangle divided into rows and columns corresponds, in which the intersections of the imaginary lines represent the grid point locations. The ranks will determined by the distance and number of the print wires held in the print head, while the columns are determined by the path intervals between the successive needle controls over a character width in the course of Write head shift are formed in the longitudinal direction of the line.

The drives for the selective actuation of the print needles

309815/0860 ./.

T.J. Holland 2 - 3 -

27-564

are often on the same trolley facility. Since these have a relatively large mass, one is strives to reduce this as much as possible.

Accordingly, the writing head shown in the drawing, which is intended for printing a character grid with η rows, only provided with ρ printing needles corresponding to those ρ drives are assigned.

The print needles 3 are twice the row spacing (2r) arranged one above the other. The 5 printing needles 3 combined into one unit, furthermore called needle packs, are stored diagonally displaceable within the write head 1. Take on a downward shift the printing needles 3 then enter the position shown in dashed lines, in which they are offset downwards by one row of raster dots and in the opposite direction to the carriage movement (arrow A) half a column spacing j- are shifted.

It is assumed that the printing process is carried out in a well-known manner, in which by driving the needle drives the associated print needles 3 from the write head .1 snap out against a recording medium and print them through an interposed ink ribbon.

With the start of the printing of a visual mark, the first column of the relevant character grid, the control of the character-appropriately selected printing needles 3 and their Imprint in the odd-numbered rows with immediate return of the printing pins to their original position. While the If the writing head is moved further in the direction of the arrow A, the needle package is moved diagonally in the opposite direction to the transport movement (Arrow A) moved according to the dash-dotted arrows B into the position shown in dashed lines. This new position is achieved when the carriage device has covered half a column spacing I in the row direction. Since the

30981S / 0860 · '·

ORlQiNAL INSPECTBE *

T.J.Holland 2 - l, - '2 /' ■ 3 B 6 4

Lateral offset of the printing pins 3 due to the diagonal shift is also half a column distance £, but runs against the carriage movement »are the print wires 3 still in alignment with the first column of the character grid. The now taking place, appropriate to the sign Activation of the print needles 3 thus causes a print marking in the even-numbered grid field rows first column. The needle package turns in the course of the further movement of the carriage device 2 in Pfeilrichtuttg A by one half the column spacing s back to its upper starting position back, in which the print needles 3 are now lagetiiäMg with the match the second column of the grid.

In this way, characters with η rows of raster points be recorded by a write head equipped only with s printing wires and accordingly also only s drives needed, resulting in a quite significant reduction the JYlasse to be moved leads. The diagonal movement of the needle package can be done by a special drive element that is a unit with the carriage device forms. It is even better to take the force for diagonal movement from the transport motor for longitudinal movement of the carriage, e.g. via a track provided with cams, along which the writing head moves, whereby the to be controlled, Can further reduce moving mass. In both cases, the force required to push the needle pack back and forth can be used can be reduced by one row spacing by balancing the effective mass of the needle assembly by means of a spring that the resonance frequency of the needle assembly and that of the spring is equal to or approximately equal to the frequency with which the needle package oscillates. In such a case the motion follows roughly a simple harmonic, and the print is made at the time of the reversal of direction, i.e. when the speed is at zero lies.

1 claim
1 sheet of drawing

309815/0860

ORKSIHAL INSPECT «*

Claims (1)

T.J. Holland 2. - 5 - ?? '' ■■ -Ί F) 6 Claim Print head for mosaic serial printer with a vertically arranged row of print needles, which is guided along the print line and over which the individual characters
one after the other in columns from horizontal ones
Mosaic point rows are put together, characterized in that only every second Mösaik point row one
Print needle (3) is assigned that the print needles (3) to
a needle package are summarized in the print head
(1) is mounted diagonally displaceable in such a way that the vertical offset corresponds to the distance of a row of points (r) and the horizontal displacement is equal to the path
the write head moves back in the line direction between two printing processes. 21.9.1972
vHy / sch 309815/0860 HMSi ³ ECTBD Blank page