DE1196236B - Playback device, in particular for electrical image transmission systems - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

H04n

German class: 21 al - 32/01

Number: 1196 236

File number: T18965 VIII a / 21 al

Filing date: September 5, 1960

Opening day: July 8, 1965

The invention relates to a playback device, in particular for electrical image transmission systems, with a pressure element and a counter-pressure element, between which a recording material runs, on which a pressure can be exerted with the help of a cutting edge located on the pressure element, that the pressure element is moved towards the counter-pressure element by the excitation of an electromagnet will.

In the known playback devices of the aforementioned type, the pressure member now acts always a restoring force, for example a spring force or gravity, so that the pressure element represents an oscillatory system which is known to have certain natural frequencies. If now the rhythm of the magnetic driving force is close to a natural frequency of the vibratory System, resonance phenomena occur, but these are extremely undesirable, as this unnecessarily limits the playback speed.

Furthermore, a playback device is already known in which an electrical discharge counteracts sensitive recording material used

Playback device, in particular for electrical image transmission systems

Applicant:

Litton Systems, Inc.,

College Park, Md. (V. St. A.)

Representative:

Dipl.-Ing. M. Licht and Dr. R. Schmidt, Patent Attorneys, Munich 2, Theresienstr. 33

Named as inventor:

Austin G. Cooley, New York, N.Y. (V. St. A.)

Claimed priority:
V. St. v. America September 14, 1959 (839 959)

Signals that the recording material is not smeared.

The configuration according to the invention is

is, against which a freely movable in a bore 25 achieved that the pressure member is not vibration-mounted Constant pressure recording pen represents more capable system. So it can't is pressed. The recording takes place through resonance phenomena, which change the how which would limit the playback speed of the recording pen. Since out-of-the-way electrical signal currents. The drive force no longer has a restoring force on the drawing pen If an electrode is used to counteract this, it can have a higher sensitivity and output device, which achieves a finer gradation of the image recording for recording un- desired pressure fluctuations, which are from a number. Since the invention is free from restoring Sources of interference can originate, freely movably supported pressure element in rest position in unmounted is. arranged in the immediate vicinity of the recording material

The invention is now based on the object, 35 is, that is, a playback device of the type mentioned at the beginning and therefore for playback only a very small amount, in which a pressure-sensitive recording material is used, ie in which several recordings are made at the same time can,
designed in such a way that no resonance disc 40
voltages occur.

According to the invention, this is now achieved by
that the pressure member is free from in the direction of the
Counter-pressure organ and in the opposite to it
Direction acting restoring forces is stored. 45 shown device,

The pressure element preferably forms the anchor of FIG. 3 shows a section along the line 3-3

electromagnet used for excitation and has Fig. 1,
the shape of an elongated plate or a fig. 4 shows a side view of an embodiment;

elongated round rod. The pressure member can almost rest against the receiving material compared to the rest position shown in FIG.
adjusted by electromagnetic means in this way. FIG. 5 is a section along the line 5-5 of FIG

it can be that in the absence of reproduction- Fig. 4,

509 599/144

If the amount needs to be deflected from the rest position, extremely high playback speeds can be achieved achieve.

The invention will now be explained in more detail with reference to drawings, in which shows

F i g. 1 is a side view of a playback device according to the invention,

FIG. 2 is a front view of the part shown in FIG. 1

3 4

F i g. 6 a further modified embodiment, is arranged that the upper edge and the

Fig. 7 is a section along line 7-7 of playback hammer 14 in a very small area

Fig. 6, cut. As can be seen in more detail from FIG. 2,

F i g. 8, 9, 10 embodiments of the re-running of the hammer 14 parallel to the length of the imaging hammer the F i g. 1 to 7, 5 sampler 13 so that the leading edge of the hammer

9A, 10A side views of FIGS. 9 and 10, 14 with rotation of the image scanner 13, the screw

11 shows a view of an embodiment of the linearly extending rib crosses. The anvil, running in a spiral shape, is advanced in a known manner with respect to the

Fig. 12 is a section along the line 12-12 of rotation of the image scanner 13 controlled so that the Fig. 11, ίο receiving sheet 10 along successive

13 shows a further embodiment of the invention - linear scanning lines are scanned and by coning, cutting of the front edge of the playback hammer

14 a schematic representation of a white 14 with the upper edge of the helically connected

further embodiment of the invention and running rib 19 each of these linear lines in

15 shows a section in which a part of another 15 successive small area is scanned,

Ren embodiment of an anvil is shown. The playback hammer 14 is freely floating

In Figs. 1, 2 and 3 the more important parts are arranged and indicated by the between him and the lines of magnetic force following the present drum 17 of an image recording apparatus Invention shown. The number 10 denotes a pressed against the paper tape 10. To this end The tape or sheet of a per se known recording ao is that of a thin metal tape made of magnetizing material. The recording material can, for example, be playback hammer 14 consisting of free material Paper or other material, the surface of which rests on a flat surface of a leg 20 of the is covered with a pressure-sensitive coating. Core 21 of an electromagnet 22 stored. Of the Such linings are known and usually so- Electromagnet 22 extends along the whole create that they are normally opaque or 25 width of the paper tape 10 and is at least one are not translucent, but provided on the elongated winding 23 speaking. Make translucent or translucent spots on the opposite leg 24 of the electrode a pressure is exerted. It can also be the magnet 22 is preferably designed so that he Places of the covering are completely removed, on is close to the rib 19. The face of the which a pressure is exerted so that the color of the 3 ° leg 24 can still be formed Underlay comes to the fore and what you want it to be that it is curved in its shape visible image. In the American patent surface of the drum 17 matches, whereby For example, documents 2 313 808 and 2 313 810 are the reluctance of the magnetic circuit such pressure-sensitive recording materials is reduced. Described to achieve a free float. 35 the storage of the playback hammer 14 this rests

The receiving tape 10 can of course not only on a number of low-friction bearing members,

consist of a single sheet, but it can, for example, on ball bearings or roller bearings 25,

also two or more similar sheets of paper on top of each other - placed in a suitable manner on the top of the

be placed. In this way kels 20 can be arranged at the same time. These bearings can be on

multiple recordings can be made. For example 40 costs of speed and operational safety

a pressure-sensitive sheet will also be omitted as the top sheet. The playback hammer 14

10 used that over ordinary sheets of paper is provided with two slits 26, 27, which are used to guide

Lies, between which carbon paper is inserted. Serve in tion and in which two on the leg 20 are

the drawing, however, only a fixed pins 28, 29 are seated for the sake of simplicity. The slots and pins

only pressure sensitive sheet shown. 45 are designed so that the free-floating movement

The application of the playback hammer 14 originating from a supply roll 11 by friction

Receiving tape 10 is not disturbed by one or more deflection forces.

roll 12 and then between an image scanner 13 As can be seen from Fig. 1, the elongated and an elongated playback hammer 14 protrudes elongated and flat playback hammer 14 passed through. The paper then runs over 50 the leg 20 and into the magnetic gap 30 two feed rollers 15, 16 on a suitable take-up, the one between the leg 20 and the take-up roller (not shown). The paper 10 is provided in a known manner in the direction of the arrow with a drum 17 provided in magnetic return line. The playback hammer 14 is moved at a speed which, in a fixed relationship, is a movable armature of an electromagnet to the speed of rotation of the image pick-up 55 and can be used to point to a feeler 13. The front edge 14A of the hammer has a certain area of the paper tape 10 that presses against the paper 10, is preferably to exert pressure. This surface is inclined in the direction of the paper feed or the intersection of the leading edge of the playback double-sided sheet. mers 14 and the upper edge of the rib 19 is determined.

The image scanner 13 consists of a drum 17, 60. When the winding 33 is excited, the reproduction

the iron or other ferromagnetic hammer 14 moved to the paper tape 10,

Material consists and on a suitable drive so that thereby the magnetic resistance in the

shaft 18 is mounted, which at a speed through the legs 20 and 24 and through the drum

is driven, which is reduced to the speed of the mel 17 formed magnetic circuit. If

Feed rollers 15,16 has a certain relationship. 65 the electromagnet is no longer excited,

The peripheral surface of the drum 17 is provided with a remains of the playback hammer 14 in place,

helically extending rib 19 since no spring forces or the like act on it. At

see, which has a very narrow upper edge and so place of the horizontal arrangement can be re-

gabehammerl4 also a little down on the drum 17 are inclined so that it rests on the paper tape 10 due to its weight. This normal Concern does not produce any characters on the paper tape 10 if there is no current flowing in the winding 23. The excitation of the winding 23 is controlled by a known image signal source 31. This source is connected in a manner known per se to a movable scanning system that synchronizes with the Drum 17 is driven, so that the electrical signals of a scanned image area on the transmitter side are synchronized with the corresponding surface on the paper tape 10. With the described Arrangement, the received image signals can accurately reflect the pressure of the leading edge of the playback hammer 14 steer to the receiving belt 10. This pressure can be between a lower limit, at which no pixel is formed, and an upper limit at which the darkest pixel is formed is changed so that a uniform gradation between white and black is achieved can be. When image signals are supplied to the winding 23, the reproducing hammer 14 becomes against the surface of the paper tape 10 and therefore also against the helical one Rib 19 pressed, whereby a pressure is exerted on the currently scanned surface. Have the image signals have the value zero or only a very small amplitude, so there is no pressure on the paper exercised and there is therefore no picture. Normally the playback hammer 14 is located always on the paper tape 10, so that the image signals for generating a pixel a certain Must have a minimum value. Normally, the playback hammer 14 moves only a fraction of a millimeter. Should the recordings be recorded simultaneously on several sheets of paper placed one on top of the other slightly higher pressure may be required. This pressure can normally can be adjusted depending on the hardness or the pressure-sensitive properties of the paper covering. Since in each case the playback hammer 14 moves very little, for example by a fraction of a millimeter, and the playback head can be made of thin and light material and since its movement is not hindered, the playback speed in the Compared to known mechanical playback devices, in which one with a helical extending web provided drum is used, can be increased considerably.

The invention is not restricted to any particular embodiment. For explanation, see in F i g. 2 shows a base frame 32 with two stands 33, 34 in which the shaft 18 of the image scanner 13 is rotatably mounted. The image scanner 13 can be operated in a manner known per se by a synchronous motor 35 are driven.

4 and 5, another embodiment of the playback hammer 14 is shown. Instead of one thin, flat metal strip, a round rod 36 made of magnetizable material is used. The round bar can roll on the flat surface of the leg 20, but not move in the axial direction, since suitable flanges 37, 38 are arranged at the two ends of the leg. In this embodiment the round rod 36 is freely movable and is due to the feed movement of the paper tape 10 rotated about its longitudinal axis, thereby avoiding any unilateral wear that occurs at the contact point with the recording material. The round bar 36 here again forms in Form a single member of both the movable armature and the playback hammer of the playback device and is arranged in the air gap 30 described above.

The present invention is of course not limited to the type of receiver illustrated in more detail in FIGS limited, but it can also be used with other types. In the F i g. 6th and Fig. 7 shows an image receiver, for example, as described in more detail in British patent specification 720036. An endless metal belt runs

39 around two rollers 40 and 41. The tape carries a chisel-shaped anvil 42 made of magnetizable Material. Several such anvils can also be used. One of the roles, for example the roller 41 is driven synchronously so that the anvil 42 at the required synchronous speed can be moved across the width of the paper tape 10. In FIG. 6 are the roles

40 and 41 omitted. The drive for belt 39 and anvil 42 is in British Patent 721776 described in more detail. A magnetically displaceable playback hammer operates with the anvil 42 14 of the type described above. By exciting the electromagnet winding 22 a precisely regulated pressure can be exerted on the paper tape 10 with the aid of this playback hammer will. Playback hammer 14 and anvil 42 operate essentially in the same Way together, as has already been shown in Fig. 1 with reference to the elements 14 and 19. So that Leading edge of the anvil 42 is worn evenly, the rollers 40 and 41 are arranged so that that their connecting line with respect to the longitudinal axis of the playback hammer 14 is slightly inclined. Through this is also the upper run 43 of the tape opposite the edge of the playback hammer 14 shifted slightly so that the chisel-shaped edge of the anvil 42 is worn evenly. Both the one made of a flat, thin metal strip (Fig. 1 to 3) and that made of a round bar (Fig. 4 and 5) existing playback hammer 14 is rigid in the longitudinal direction. However, it can with be advantageous in some cases if the playback hammer is somewhat flexible in the longitudinal direction. In Fig. 8 shows a playback hammer 14 which is provided with side slots 44 formed in something larger openings 45 end. The playback hammer 14 is thereby somewhat flexible, which doubles The advantage is that it can nestle against any unevenness in the spiral anvil and that still at very high playback speeds of the anlie ^ on the spiral web 19 lowing part of the playback hammer is bent so that it is not necessary that the entire Length of the playback head moved at the same speed in the direction of the drum will. The hammer is thus freely displaceable as a whole, while a part of the hammer that is just effective can also bend. There are other ways in which the replay hammer can also be used in Be made flexible in the longitudinal direction. 9 and 9A is another embodiment of a bendable hammer shown here, the shape here

has a coil 46 wound from iron wire, on which a thin, flexible wire 47 is attached, in a manner similar to the end edge 14 ^ 4 of the one shown in FIG Playback hammer 14 acts as a marker S cutting edge. As shown in Figs. 10 and 10A is, several smaller elements 48 can be used instead of a flexible element, which are shown in FIG Are held together in the longitudinal direction by a flexible cord 49.

11 and 12 is another embodiment of the image scanner 13 shown in Figs. In this embodiment is on the shaft 18 a cast part 50 keyed or otherwise applied, which is made of a light, not magnetizable material, for example aluminum, and is shaped like a helix. on the helical, flat surface of the casting is a ferromagnetic plate

51 welded, which the magnetic flux that in the electromagnet 22 (Fig. 1) is excited by an image signal, between the playback hammer 14 and the paper tape 10 with local enlargement of the intensity. The top of the plate 51 can with be provided with a central groove in which a steel wire

52 can be admitted. The steel wire 52 corresponds the spiral-shaped rib according to FIGS. 1 to 5. The plate 51 can in place of the wire also be provided with a protruding rib that is machined from the plate.

In Fig. 13 is a modified form of the the F i g. 1 to 5 shown embodiment shown. The playback hammer 14 is between two Roller bearings 53, 54 are arranged, which in turn are in a rectangular opening of the magnet winding 23 lie. The elongated magnet winding 23 is similar to that in FIG. 1 magnet winding shown built up. One end edge of the playback hammer 14 is at the magnetic gap between the leg 20 and the image scanner 13 are arranged.

Fig. 14 shows a somewhat modified arrangement for guiding the playback hammer 14. In this one In the embodiment, the hammer 14 is suspended from thin wires 55, 56, 57, 58 on a fixed plate 59 and is so slightly above the top of the leg 22. The hammer is freely movable and can be attracted when the electromagnet is excited by image signals from the image scanner.

Fig. 15 shows a modified embodiment of an anvil. Similar to FIG. 12 is a cylindrical part 55 is provided with a helically extending rib 50. About the weight to reduce the rotating parts, the part 50 and the rib 55 can be made of aluminum or any other light metal alloy. One in one serves as a magnetic line On the surface of the rib 50 extending groove inserted iron insert, which consists of a series of Consists of lamellae and protrudes over the edge of the rib 50. One or more in the middle Lamellae are somewhat shorter, so that a central groove is created into which a wire 52 is welded, soldered or otherwise attached.

Claims (16)

Patent claims: 1. Playback device, in particular for electrical image transmission systems, with a Pressure element and a counter-pressure element between which a recording material runs, on which a pressure is thereby exerted with the help of a cutting edge located on the pressure element can be that the pressure member by exciting an electromagnet on the counter-pressure member is moved to, characterized in that the pressure member (14) is free of in Direction on the counter-pressure element (19) and acting in the opposite direction Restoring forces is stored. 2. Playback device according to claim 1, characterized in that the pressure element (14) the armature of the electromagnet (22) and the position of the pressure element (14) essentially controlled solely by the excitation of the electromagnet. 3. Playback device according to claim 1 and 2, characterized by a magnetic Component (17) on the side of the receiving material (10) opposite the pressure element (14), by a flow of lines of force in the direction of movement of the pressure member (14) through the receiving material (10) through to the counter-pressure member (19) is achieved. 4. Playback device according to claim 3, characterized in that the counter-pressure member (19) supporting drum (17) or a part of this drum the magnetic component forms. 5. Playback device according to claim 1 to 4, characterized in that the core (21) of the electromagnet (22) has a smooth surface on which the pressure member forming the armature (14) is performed. 6. Playback device according to claim 5, characterized in that the forming the anchor The pressure element (14) is a round rod (36) which is placed on the smooth surface of the magnetic core (21) is stored freely unrollable. 7. Playback device according to claim 5, characterized in that the forming the anchor Pressure member (14) is a thin flat plate that rests on the smooth surface of the magnetic core (21) is slidably mounted, preferably with the help of slots (26, 27) in which of the smooth surface of the core (21) protruding pins (28, 29) sit. 8. Playback device according to claim 7, characterized in that the storage under Interposition of ball bearings or roller bearings (25) takes place. 9. Playback device according to claim 7 and 8, characterized in that the cutting edge (14A) of the plate is bent in the direction of movement of the recording material (10). 10. Playback device according to claim 1 to 5, characterized in that the pressure member (14) is essentially rigid in its longitudinal direction, but at any point where characters are recorded on the recording material at a given moment, can be bent in the transverse direction. 11. Reproduction device according to claim 10, characterized in that the pressure member (14) is provided with transverse slots (44) which enable it to be bent in the transverse direction. 12. Playback device according to claim 10, characterized in that the pressure member (14) is a helical spring (46) on which a thin, flexible wire (47) is attached. 13. Reproduction device according to claim 10, characterized in that the pressure member (14) composed of adjacent links, usually arranged in a straight line (48) consists, which, under the action of the electromagnet (22), individually in the direction of the recording material (10) are movable. 14. Reproduction device according to claim 1 to 13, in which the pressure member is an in Has a longitudinal cutting edge that is shaped like a screw Crossed cutting edge of the counter-pressure member, characterized in that the electromagnet (22) surrounds the pressure element (14) lengthways, whereby it is directly through electromagnetic Effect is moved in the transverse direction without a substantial displacement occurs in the longitudinal direction. 15. Playback device according to claim 3 to 14, characterized in that the counter-pressure member (19) a screw-shaped casting (50) made of a non-magnetizable Light metal alloy, on the edge of which is a screw-shaped end piece Strip (51) of magnetizable material is attached, on which in turn a helical running edge (52) sits. 16. Playback device according to claim 3 to 14, characterized in that the counter-pressure member (19) is an anvil (42) with a chisel-shaped edge, which is also the magnetic Forms component and which is mounted on a moving belt (39) and with the Printing element (14) defines a pixel on the recording material (10), which is in correspondence moved with the tape movement across the width of the recording material (10). Considered publications:
German Patent Nos. 669146, 895 909;
U.S. Patent No. 2,591,138. For this purpose 2 sheets of drawings 509 599/14 * 6.65 © Bundesdruckerei Berlin