DE681442C - Printing telegraph receiver, in which the received pulses are recorded as pixels on a strip of paper - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
SEPTEMBER 12, 1939

REICH PATENT OFFICE

PATENT LETTERING

JV £ 681442 CLASS 21 al GROUP 11 oi

158402 VIIIaJ2ia>

Lucien Devaux in Paris

has been named as the inventor.

can be recorded on a strip of paper

Patented in the German Empire on June 27, 1937 from the date of patent issue, published on August 31, 193g

With a large number of known telegraph receivers, especially those in which letters and characters are strung together Points are represented, it is necessary to have a very high speed of the part recording the points. For this purpose are electromagnetic Systems have been used whose moving part is very light and which to

ίο to achieve a quick movement of the anchor, need a relatively strong current.

The present invention solves the existing problem in that the controller of the pressure member is effected by an arrangement that has the properties of piezoelectric Crystals used. It is known that there are two or more lamellas units let build, which, if these slats are provided with connections and between Voltage differences occur at these connections, corresponding to the voltage difference Turn in one direction or the other. This process becomes the subject matter of the invention exploited. Rochelle salt (a double tartrate of potassium and sodium), since experiments have shown that with Using the same voltage differences compared to other crystals makes a considerable difference greater deflection takes place.

Such an arrangement can be used to either operate a pen, the carbon paper presses on the recording strip, or to drive a blade that lifts the paper strip and moved it against a carbon paper, on the other side a solid one. Stop is located. This stop can for example consist of a small plate in which the movable Pins are provided, or from another appropriately working input

direction. In the following this movable device is used as a print hammer. draws. The advantage of the arrangement according to the invention is that it is a very rapid movement that precisely follows the rhythm of the transference, and that furthermore, no permanent power consumption is necessary in the arrangement. It is more than enough to create a voltage difference in order to ίο achieve an impression. the The amplitude of the movement of the piezoelectric crystal is generally too small to to operate the print hammer directly. However, since the pressures achieved are high, it is possible to control the movement by mechanical means, e.g. B. a lever arrangement, or by other devices, "such as pneumatic devices, to be strengthened.

Fig. Ι shows schematically such an order, how it comes into question for a telegraph receiver. The piezoelectric Receiving device 1 consists of several superimposed crystal plates, have a rectangular shape and at three corners with the help of elastic plates 2, e.g. Rubber, to be held together. The plates are cut so that during production a voltage difference between the connections 3 and 4 the individual strips bend so that the free corner S is on a perpendicular to the plane of the strips lying line moves. This corner is connected to a small pin 6, the one Lever 7 rotatable about axis 8 is actuated. The other end of the lever carries the print hammer.

In the arrangement shown, the small print hammer 9 strikes the one in the slide 17 arranged pins 10 to 16 and causes thus pressing down the ink ribbon 18 onto the paper strip 19. The slider 17 receives a reciprocating motion that is synchronized with the transmitter, so that the pins ι ο to 16 on parallel lines; run and record 9 dots and lines according to the way the print hammer works, creating the individual letters are formed. The slider 17 can e.g. Axis sits, can be moved back and forth, whereby the cam disk for one revolution triggered at the beginning of the reception of a pulse to record a letter will.

The movement of the lever can be doubled without reducing the stress of the crystal. is enlarged. The receiving circuit can be arranged for this purpose that in the state of rest the crystal is polarized in one direction and that the reception of characters has a polarization to the opposite side, but from same size, causes. Such an arrangement is shown in FIG. 2, for example. The piezoelectric crystal 20 is switched into the diagonal of a Wheatstone bridge, at the two. Branches are formed by equal resistors 22 and 23 while the other two branches consist of two electron tubes 24 and 25. The grid the tube 24 is normally biased so that the resistance of the tube is considerable is, while the tube 2 5 represents a relatively small resistance.

This results in a polarization of the crystal in one direction. In the grid circle of the tubes 24 and 25, respectively, diodes 26 and 27 are switched on, their circuits with the last tuned circuit 28 of the receiving station are connected so that a Received pulse makes the grid of the tube 24 positive.

The bridge is therefore unbalanced in the opposite direction, and thus the polarization of the piezoelectric elements is also reversed.

The invention is not limited to the embodiment described above, but also applicable in other forms. It is Z. B. possible instead of a single piezoelectric arrangement a plurality of such arrangements in different transmission channels to. use, being in those cases where each is a sign Composite pulses are transmitted through different channels, each arrangement operated a special print hammer.

Claims (6)

Patent claims: 1. Pressure telegraph receiver, in which the received "impulses as pixels recorded on a strip of paper and the individual characters to be reproduced are formed by these pixels, characterized in that the pulses received are opposite sides, one made of piezoelectric material produced plate are fed, which in turn under the effect of Im- no pulse operated a print hammer. 2. Printing telegraph receiver according to claim i, characterized in that the Plate made of several identical lamellas, each made of a piezoelectric Crystal are cut, is composed. ■ · 3. Pressure telegraph receiver according to claim ι and 2, characterized in that that as a piezoelectric material Ro- »20 chelle salt is used. 4. Print telegraph receiver after arrival claim i to 3, characterized that the print hammer is made with the help of a lever from one of the corners of the piezoelectric Material existing rectangular plate is actuated. 5. Print telegraph receiver after. Claim ι to 4, characterized in that the piezoelectric plate is normally in _; is polarized in one direction and the received pulses cause a polarization in the opposite direction for the purpose of actuating the print hammer. 6. Pressure telegraph receiver according to claim ι to 5, characterized in that that the piezoelectric plate is in one diagonal of a Wheatstone bridge is located, which contains electron tubes in two adjacent branches, on their grid such voltages are that one of the tubes normally has a small "Resistance, the other has a very high resistance and that the received Pulses are fed to the grids so that their voltages are reversed. 1 ßlalt drawings