DE2805695A1 - PEN FOR TIP RECORDER OR PRINTER - Google Patents

Description

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The invention relates to impact writers or printers
and in particular to writing heads and pens for such impact matrix writing devices.

Printing or writing devices for relatively fast writing or printing often use impact matrix pens or
-Printers in which the characters to be printed or written are formed in that each character is composed of a large number of individually posted matrix points. Such printers use a group of wire-like pens, their
outer ends or writing ends are selectively driven against an ink ribbon to form the individual characters. The actuation mechanisms for the wires are relatively large and unwieldy and
must therefore be placed in a location remote from the printing area. The printing or writing wire must have the ability to transmit the force from the actuating mechanism to the position where the printing process is to take place. The path between the actuating device and the writing position is usually not a straight line, since the field of actuating devices required requires a larger area than the dot matrix to be printed, so that the writing wires must therefore be routed over its length. The writing wire guides
also act to reduce deflection of the writing wires when the writing surface is struck. If the deflection were not limited, the impact force against the printing surface would be substantially reduced. In addition, the writing wire must be sufficiently robust to transmit sufficient pressure and must be resistant to abrasion forces that occur during the rapid printing process at the point of contact with the paper or a corresponding material to be printed, which develop an amazing abrasive effect under such conditions.

Because of the rather specific manufacturing requirements for such Pens that not only benefit from the flexibility in

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direction, but also the total mass, from the point of view of the Printing speed and actuation force requirements is very important, and abrasion resistance is one of the finishes that The previous pens were used when the medium to be printed on, usually paper with an astonishingly high abrasion effect, strikes almost always of the same fundamental nature, regardless of the specific type of writer or printer, in which they are used, i.e. the previous pens have almost always been made of solid tungsten wire material.

In one known type of write head, most of the length of a write wire is flexible from a guide sleeve Enclosed material, for example by a helically wound wire, commonly known as a Bowden cable. In this way, for example, the middle wire of a Bowden cable can be arranged serve as writing wire, the wire falling over the end of the flexible cable sheath in a dot matrix or in a fixed guide element leading to the matrix area extends. The construction of a Bowden cable is such that an essential one Some of the energy used to bend the cable is lost because of the friction along each wire and its sheath. the Reducing such friction is particularly difficult because the sheath surrounds a substantial length of the wire; to this There is a large surface contact between the middle wire and the wrapped wire sheath. Furthermore, if the middle wire bends during the writing process. Parts of the middle wire against the inner wall of the sheath with essential increased force and produce an increased frictional resistance to the movement of the central wire.

Such bending and the resulting friction causes the writing wires to work inefficiently and the May have a tendency to become detached from their actuators. However, it is necessary to extend the writing wires along their length guide and such flexible guide sleeves fulfill this function, although it is also necessary to use other guides or positioning devices to be covered over the corresponding length of the sheathed cable

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turn, in most cases at appropriate intervals are arranged, which allow bending of the cables between such outer guides. The orders prior art attempts to prevent such deflection by built-in and spaced-apart brackets that are connected to the coil of the Bowden cable or over the length of the writing wire, where a sheath is not is used; further use is made of encapsulating the entire cable in a plastic material. Even if such Try the manufacturing cost of such Bowden cable assemblies have increased, they still have not eliminated the loss of energy when using a Bow3en cable, since in particular only very small amounts of energy are stored by the compression of the writing wire itself.

The Bowden cable arrangement provides a substantially continuous one Guide means as well as other prior art arrangements such as those in which the writing wire passes through the central opening of a hollow tube rather than a coiled cable. As with the Bowden cable arrangement friction occurs between the central writing wire and the surrounding sheath or tube. Continued rubbing of the Writing wire against the inside of the sleeve can cause the sleeve to be chafed through and allow the writing wire to to step out of the envelope so that it is no longer guided into its writing position.

The prior art arrangements also use discrete ones Guides that are arranged at frequent or close intervals, such as every 1.8 cm. A significant disadvantage of such arrangements consists in the friction between the stylus and each guide, which the stylus as it passes through the guide weakens and can break the stylus. Such an arrangement is also very inefficient and stores little energy and gives off little energy.

Based on the prior art explained above, it is the task the invention to provide a novel pen that

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ORIGINAL INSPECTED

is essentially free from the stated disadvantages.

The pen according to the invention has improved energy storage, if it is deflected, reduced friction during the writing process, a simplified write head arrangement, moving parts of less weight as well as a higher writing speed with the same amount of energy. Furthermore, according to the invention, a manner is specified in which such pens is mounted in a write head with a reduced number of guide devices. There is also a pen with variable mass and variable bending properties specified over its length, so that the available Increase the standing design parameters considerably and flexibilities and arrangements in operation are made possible were previously unavailable.

To achieve these properties, the pen is equipped with two integral parts that have different structures. A front part is specially adapted in order to have a well-defined writing imprint on a to be written on or to deliver the area to be printed. An axially connected rear part is specially adapted to to transmit a pressure or typing force from an actuator to the front part, and is specially designed for fast Power transmission to the front part designed to bring the pen into an operative position and the pen quickly to bring it back to its rest position.

The front part has an elongated fixed stylus in the axial direction with a longitudinal axis of symmetry Delivery of a stop force to produce a printed impact on a surface to be printed. Advantageously the material for this stylus part is resistant to the abrasive forces that occur when it hits the writing surface occur while the stylus is sideways across it

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moved with at least momentary frictional contact between them. An integrally formed, axially connected and axially Direction of elongated rear drive element is connected to the front stylus part and connects the latter with one Actuating device for moving the assembled pen. The rear drive element is preferably less flexible than the front stylus, so that the pen on this way is equipped with sufficient strength to the Use fewer guides to allow the pen between its actuator and the front one Carry the end of the stylus close to the writing surface.

The use of fewer guides is advantageous because fewer Energy losses occur due to the friction between the guides and the pen and the pen in turn uses energy can save by deflection. This means that in the invention Arrangement recognized the deflection as a more desirable form of energy storage than compression has been, with the fewer number of guides the frictional energy losses reduce while at the same time allowing the desired degree of deflection. If accordingly a deflection of the pen takes place, an improved energy storage occurs, which has the tendency that Size of the speed of the pen on the writing surface and the size of the speed of the pen from the Compensate for writing surface. The reduced use of guides also reduces the criticality of the dimensions of the Pen and simplifies manufacture. This means that the parts of the arranged in the longitudinal direction between the guides Pen need not be adapted for passage through the guides and may have local deviations, without affecting its effectiveness and functionality. The integrity in terms of structure and alignment is not critical as the frictional engagement is significantly reduced with the stylus guide does not cause the

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Arrangement as in the case of those according to the state of the art.

In an embodiment according to the invention, for example the properties of the stylus, i.e. the front part, are obtained by making an elongated cylindrical solid tungsten part used, while the properties of the drive element are achieved by having an elongated Part made of stainless steel with an elongated cavity used, so that the cross section of the drive element for example has the shape of a U or ring-shaped. According to a further feature of the invention, the weight of the entire pen is less than the weight of a fixed stylus of equivalent length. That means that the hollow Drive element compared to the compact stylus saves weight and actuation with a reduced amount of energy enables.

In another embodiment according to the invention, a novel nib is provided for the pen, primarily as Return spring is used, but is not necessarily limited to such use, such Spring has a leaf spring part that carries the pen at or near one end and also drives it, namely in its rewind or some other position. Such a spring forms a cantilevered pen holder and a spring preload, in which the middle part is fixed and at least one of the outwardly protruding arm parts is designed so that it is elastically deflectable with respect to the central part. Preferably, the outwardly protruding arm is provided with one extending therethrough Provided opening in which the pen is received. In a preferred embodiment, the spring has at least two such outwardly projecting arm parts, which are arranged opposite one another or symmetrically to one another wherein the spring is used in a stacked arrangement with other such spring units to form a fan-shaped panel,

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which cooperates with a corresponding field of pens.

Further features and advantages of the invention are to be found in the following on the basis of implementation examples and the associated Drawings are explained in more detail. The drawing shows in

Fig. 1 is a front perspective view of part of a write head according to the invention;

2 shows a partial cross-section in the longitudinal direction of a pen and the guidance of an arrangement in accordance with the invention;

3 shows a cross section of a drive element of a pen a preferred embodiment of the invention along the plane III-III of FIG. 2;

4 shows a cross section similar to FIG. 3 to explain another embodiment of the drive element of a Pen according to the invention;

FIG. 5 shows a cross section similar to FIG. 3 of a further embodiment a drive element of a pen according to the invention;

6 shows a graphic illustration to explain the speed-time dependency a pen according to the invention;

7 is a graphical illustration for explaining the speed-time dependency a pen that stores energy solely through compression;

8 shows a graphical illustration for explaining the speed-time dependency a pen that stores energy solely by bending;

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9 shows a partial cross-section similar to FIG. 2 in the longitudinal direction to explain a cantilevered pen nib of a pen according to the invention;

10 is an enlarged plan view of a cantilever pen nib according to Fig. 9;

11 shows an array of a plurality of leaf springs shown in FIG. 9 which are arranged in a fan-like manner; and in

Fig. 12 is a section through the fan-shaped arrangement along the Level XII-XII of FIG. 11.

As can be seen from Fig. 1, a write head 10 has a plurality of elongated pens 20 with front ends 20a, which are in a desired Field or pattern, such as a vertical column, and with opposite ends 20b which are attached to Actuators 11 to provide a driving force for the Pens 20 are connected in the longitudinal direction, the actuators usually connected to solenoids Plates are. About the length of each individual pen 20 are Arranged guides 12, 13, 14 and 15, each having a plurality of holes and each receiving individual pens 20. Each pen 20 has a needle 21 in the front part and a drive element 22 in the rear.

As indicated in Fig. 2, the pen 20 is preferably with an elongated solid tungsten part as a needle 21 of generally cylindrical shape and a drive element 22 is provided, which can be of different shape or type and is aligned with and connected to needle 21. That Drive element 22 has an elongated cavity 25 in the longitudinal direction, which is preferably formed in that the drive element 22 is in a hollow tube arrangement with an annular cross-section is installed. Alternatively, an actuator 22a, such as

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indicated in Figs. 4 and 5, a generally U-shaped cross-section, like the channel-like part in Fig. 4, or semicircular Have cross-section, like the embodiment of FIG means that the cavity is exposed in the longitudinal direction in the embodiment shown in FIG. 3 in the longitudinal direction of the environment instead of being surrounded by the drive element. One end of the needle 21 is inserted into one end of the cavity 25 and in attached to its position. The drive element 22 can be attached to the needle 21 by various means, for example by firmly squeezing the drive element 22 around the needle

21 or by soldering or brazing using a metal part 30 (see FIG. 2), for example made of silver, or by electron beam welding. Furthermore it may be pointed out be that the advantages are very generally with a pen of the type specified above with a needle in the front area, their Cross-section differs in size or shape from that of the rear part, can be achieved if you have a drained pipe or another internally hollow part is used and the front end connects to a part of different shape or shape, wherein the connection of such an end takes place, for example, to the extent that its inner diameter corresponds to the inside of the pipe at its front end closes or substantially closes or fills in to increase its weight and change its flexibility, Openings in the guides 12 and 13 receive the needle 21 and they carry, while openings in the guides 14 and 15 receive and carry the drive element 22.

An end cap 24 is in the rear end of the drive element

22 is used, which is opposite the end connected to the needle 21. The end cap 24 usually consists of one elastic material for damping an actuation force on the drive element 22. The end cap 24 is generally more massive cylindrical shape with an enlarged head part 24b and a smaller foot part 24a, the cross-section of which is approximately the same cross-section and the same size as the cavity 25 and in this

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is recorded. A helical spring 23 is telescoped over the drive element 22 between the guide 15 and one of the enlarged Head 24b forming the flange of the end cap 24 is set. The helical spring 23 acts in such a way that it stores energy, when the pen 20 is pushed forwards, i.e. to the right in the arrangement according to FIG. 2, into a writing position, and supports the return movement of the pen 20 to the left into its rest position. In this embodiment there is a helical spring 23 reproduced to provide a first more or less typical arrangement of the pen; in other embodiments, which in the following approximately in connection with FIGS. 9 and to be explained in more detail, a very special form of a spring 123 is used.

Preferred materials for needle 21 include tungsten, tungsten coated stainless steel, or tungsten carbide. to the materials for the drive member 22 include stainless steel and copper beryllium. Tungsten is a particularly beneficial one Material for the needle 21 as it has good resistance possesses against abrasion. During a rapid printing process, the needle 21 experiences impact forces against a writing surface and Abrasive forces through its path against the surface of the writing surface. The selection of a material for the drive element 22 is in connection with the desired physical arrangement and the Execution properties of the drive element 22 taken to a desired hatred of strength and the desired mass properties to reach. This means that a thin-walled drive element made of one material has the same strength as one may have thicker-walled drive element made of a different material, although the spring rate and the mass of the two are likely to be different will distinguish. At the present time, for reasons of ease of manufacture, there is an arrangement with a thin pipe is preferable if the wall is thick enough for easy handling without crushing. If the Arrangement can be automatically created without manual processing can what eliminates the possibility of crushing it can

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be desirable to have a pen with a thin wall and large diameter and lighter weight.

In a particular embodiment, the cylindrical Stainless steel tube as the drive element has an outside diameter of 1 mm (0.040 inch), a wall thickness of 0.076 mm (0.003 inches) and a length of 70.9 mm (2.792 inches). The front one The part designed as a stylus consists of solid tungsten wire with a length of 34.5 mm (1.358 inches) and a diameter 0.35 mm (0.014 inch). Such an arrangement has the weld surface between the needle 21 and the drive element 22 lengthways one 2.3 mm (0.09 inch) length and one typical length of the flange of the head part 24b of 0.64 mm (0.025 inch). For example, dimensions for a semicircular

Drive element 22 are 1.3 ram (0.050 inch) in diameter and a wall thickness of 0.025 mm (0.001 inch). A channel-shaped drive element 22 can have a floor length of 1.3 mm (0.05 inch) have a side wall height of 0.64 mm (0.025 inch) and a wall thickness of 0.025 mm (0.001 inch).

Fig. 9 shows a pen 20 of the type described above, which is arranged cooperating with a leaf spring 123, the overall structure of the leaf spring 123 being shown more clearly in FIG is. The leaf spring 123 has a central body portion 125 with a central opening 127 with which the leaf spring 123 is mounted is. As is only indicated in FIG. 9 by way of example, the attachment can be carried out with the aid of a machine screw 129 and a Nut 131 take place, which hold the leaf spring firmly on a carrier, which is a rearwardly extending part 15a a rear guide 15 for the pen 20 can act; of course, the leaf spring can also be attached to another suitable one fixed element, for example with a machine screw passing through the central opening 127 129. The leaf spring 123 is characterized by one or more outwardly projecting arms 123a and 123b, each of which with a through opening 124 is provided, through which the writing

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pin extends directly inside the end cap 24. In this way, the outstretched arms of the leaf spring can serve to to carry the pen 20 directly, and for this purpose the arms of the leaf spring 123 can actually take the place of the rear Take guide 15; in this case the leaf spring would of course be central in the same basic way, but mounted on any form of central support element. In some cases it may be desirable to provide a facility to in order to keep the pen immovable in one place relative to the opening in the spring arm, e.g. by means of a fixed installation or the like, so that any longitudinal movement of the pen of is accompanied by deflection of the spring.

The leaf spring 123 is a useful and beneficial improvement represents, which can be used quite generally in many different forms of pens or impact elements; however, this type of nib also provides very favorable operating characteristics for a pen of the type described here Leaf spring is advantageously made of flat spring steel, usually on the order of a few hundredths of a millimeter Thickness (a few thousandths of an inch) so that its easy and economical manufacture can be readily understood. About that in addition, a single such nib arrangement can be readily adapted for use with two opposing writing pens be adapted and such double spring arrangements can easy to use in stacked multiples, with each additional Feather slightly opposite the other feathers to a fan-shaped one Arrangement is rotated, which is adapted to a same field or a same pattern of several pens. While the The spring thus only needs to have a single outstretched arm, it can also have a large number of such arms', i.e., a single spring assembly may have a number of different arms arranged in a star shape throughout the structure. Because of the high speeds of data writers in general, including impact matrix writers

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of the specified type, the leaf spring advantageously consists of spring steel and, in particular, of a rod alloy, such as it is used in watch springs, for example from a material available commercially under the name "Elgiloy", that has the desired fatigue strength and pod properties.

A fan-shaped or roughly star-shaped field of a multitude of leaf springs of the type indicated above is shown in Figs. 11 and 12, the first such spring with 123, the the second with 223, the third with 323, the fourth with 4 23 etc., with the outwardly extended arms on these Way form eight equally spaced pen support or spring actuators that are in a conical or cylindrical box are arranged. It should be noted that with such a field of leaf springs all are mounted concentrically in essentially the same manner as the single leaf spring 123 in FIG. Even if, how indicated above, such a field of a plurality of leaf springs is formed as an integral one-piece piece, it is assembled in a similar manner.

6 shows the speed-time dependency of the pen 20 during a printing or writing process. The speed of a pen 20 in the longitudinal direction forwards into a writing position, ie to the right in the arrangement according to FIG. 2, is defined as positive speed, while a retraction movement back to the rest position to the left is defined as negative speed. The amounts of the two speeds, ie the transition to the writing position and the return to the rest position, are approximately the same. The transition time between the maximum speed in the positive direction and the maximum speed in the negative direction is due to the time interval in both times t " ₁ and

fc_ defined. At time t ~ the speed is zero, and the pen 20 has reached its maximum deflection from its rest position.

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In one embodiment, use is made of the fact that it is advantageous if the pen is allowed to bend, because the energy in the pen is generated both by bending the pen and by compressing the pen can be saved. If the energy storage takes place essentially through compression, the reverse occurs the direction, i.e. the sign of the speed, of the pen almost instantaneously (see Fig. 7) and within a substantial shorter time than when the pen has lateral bending properties, as is the case for a typical case in Fig. is reproduced. A pen, which only stores the energy by compression, however, has one in FIG. 7 -V 'implied negative or rewind speed, which is essential is lower than the speed V of the pen when it moves forward from its rest position into its writing position emotional. This loss of speed is due to the loss of energy due to the fact that the energy storage is only done by compression. Even if there is an almost instantaneous change in direction of speed, this is also the case the return speed of the pen from the writing position to the rest position is lower than with a Pen according to the new embodiments described above.

When a pen draws the energy solely by bending it instead Compression stores, as indicated in Fig. 8, so the amount of speed in the writing position is im essentially as great as that of the return speed from the writing position to the rest position. The time interval required until the maximum speed is reached in each of the two opposite directions, however, is essential greater than in the ratios shown in FIG. In this way it is clear that a pen according to those described above new embodiments, the behavior of which in Fig. 6 is indicated, preferred aspects of each basic type of pen combined in an advantageous manner and, moreover, an arrangement and structure whose mass and flexibility differ

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can change over its length, since the front and rear parts have different structures from each other and in the Tat can consist of different materials, so that the operating properties can be changed and optimized.

The start-up time of the new pen described above is also compared to the arrangements according to the prior art decreased. In the previously known arrangements, the pen usually bounced from the rest position on the return path a distance forward that is approximately 25% of the total length of the trail of the pen. In the embodiments described above, this proportion is reduced to a percentage of approximately 5% reduced. Such a reduction in the impact distance from the rest position and the resulting reduction in the start-up time or settling time is particularly advantageous when the same needle is operated one after the other, as is the case with fast printing processes is required. The amount of energy required to actuate the needle is reduced because the more energy is lost goes the farther away a pen is from its poihestelluna is when it is pressed. The result of the reduced settling time and the reduced energy loss is a faster and more consistent printing without increasing the drive energy.

Of course, the invention is not limited to those described above Embodiments limited, for example, the relative lengths of the needle and the drive element compared to the specifically indicated fourth can be changed depending on the particular desired properties of the write head. Furthermore, the specific connection between the needle and the drive element can be changed compared to the embodiments described above.

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Claims (8)

Mr. »1, 8000 Munich 40, Frei.igralhstraBe19 nin | , R "Rflhr Eisenacher Strasse 17 Postfach ti" Dipi.-ing. R. H. Barir p «.- Anw. Pat. Hermiann-Trentepohl DlDL-PhVS. Eduard ΒβΐΖίβΓ Telephone: 36 3011 Telephone: 51013 F "J ■ 36 3012 51014 Dipl.-Ing.W. Herrmann-Trentepohl * 3013 Telegram address: Telegram address: Bahrpatente Herne PATENTANWÄLTE Babetzpat Munich Telex 08 229 853 Telex 5215360 l ~ ~ \ Bank accounts: Bavarian Vereinsbank Munich 952287 Dresdner Bank AG Herne 7-520499 Postscheckkonto Dortmund 55868-467 Ref .: •: MO 6228 Sj / hr Please indicate in the answer. Please write to: Ilünchen Abholfach 3 Sycor, Inc. 100 Phoenix Avenue Ann Arbor, Michigan (USA ) Pen for impact writer or printer claims 1.) Pen for impact writer, thereby g e k e η η lehnet, that he is a long slender wire-like element (20) with at least one guide (12, 13, 14, 15) over its length for carrying the element (20) that the pen (20) a first end (20a) with an elongated needle (21) for striking and a second part (20b) with an elongated one Drive element (22) has that the second part (20b, 22) at least has a length of the same order of magnitude as the first part (20a, 21) and is axially aligned with the first part (20a, 21) and is connected to it; that the second part (20b, 22) has a structure in the form of a long hollow column with hollow Inner areas (25) and less flexible per unit length than the first part (20a, 21), so that the number of necessary guides (12 - 15) for carrying the writing Ö0983 57 0584 L INSPECTED ■% ■ Pin (20) compared to the number of guides required (12 - 15) a pen (20) with the same flexibility as that of the First part (20a, 21) is reduced over the entire length and thus reduces the frictional resistance that the Gehreibstift (20) during is exposed to printing. 2. pen according to claim 1, characterized in that that the cross-sectional area of the smallest circle which completely surrounds the needle (21) is narrower transversely to the longitudinal axis as the cross-sectional area of the smallest, the second part (20b, 22) at right angles to the longitudinal axis completely enclosing the circle. 3. pen according to claim 1, characterized in that the length of the second part (20b, 22) in the longitudinal direction is greater than the length of the first part (20a, 21) in the longitudinal direction. 4. pen according to claim 1, characterized in that the second part (20b, 22) is a long thin slender Has tube (22). 5. pen according to claim 1, characterized in that that the cross section of the second part (20b, 22) is annular. 6. pen according to claim 1, characterized in that the needle (21) is complementary in size to open central part (25) of the ring-shaped drive element (22) has formed cross-section and that the drive element (22) receives the needle within the open central part (25, 30). 7. pen according to claim 1, characterized in that that the drive element (22) has a generally U-shaped cross-section (22a, 22b) and that the elongated cavity is inside such a cross-section is formed. 30983570584 _ ₃ _ 8. Aufschlagmatrixschrexber, characterized in that that an elongated, generally rectilinear pen (20) and guide elements (12-15) for carrying the pen (20) are provided over its length, the pen (20) having an axially elongated needle (21) for writing with a has a first and a second end, of which the first end for striking a writing surface for producing a pressure impact is designed; that an axially elongated drive element (22) in generally rectilinear alignment with the needle (21) provided and with a first end to the second end of the needle (21) is connected, while its second end (11) for receiving a force is designed for axial displacement of the pen (20), the drive element (22) at least one as well as long as the needle (21); that the drive element (22) differs in cross-section in size and geometrical configuration from the needle (21) and has less flexibility and lower mass per unit length than the needle (21); that the relative strength of the pen (20) reduces the number of load-bearing guide elements (12-15) required over the length of the pen (20) and thus the energy loss due to friction between the pen (20) and the guide elements (12-15) reduces / that the writing head (10) has a first supporting guide (12) arranged generally at the first end (20a) of the needle (21), a supporting guide (13, 14) generally arranged in the region between the first and the second end over the length of the needle (21) and a third supporting guide (15) arranged in the vicinity of the first end of the drive element (22), the drive element (22) being free of guides over the remaining part of its length . 009835/0584