US2128242A - Printing telegraph system - Google Patents

Description

/NVEN DQS 5 Sheets-Sheet l Filed May 16, 1934 G. A. GRAHAM El AL PRINTING TELEGRAPH SYSTEM Z Z W 2 .2 mm M Aug. 30, 1938 G. A. GRAHAM ET AL v 2,128,242

PRINTING TELEGRAPH SYSTEM Filed May 16, 1934 5 Sheets-Sheet 2 650965 A. GPA/744M HAPQVW RmQ/VE gi im Aug. 30, 1938. G. A. GRAHAM El AL V PRINTING TELEGRAPH SYSTEM 5 Shgets-Sheet 5 Filed May 16, 1934' 1 m 2 K .MMM h 2% .5 fl m2 7 Q a 2%? W? kw WW ow Wm Aug. 30, 1938. G. A. GRAHAM ET AL PRINTING TELEGRAPH SYSTEM 4' m Qxm m a mu 4 IM..N\

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m m u m wm H m Q A M E JZW m NR 4 1933- G. A. GRAHAM El AL 2,128,242 I PRINTING TELEGRAPH SYSTEM Filed May 16, 1934 5 Sheets-Sheet 5 IQECE/ VEQ /NVENTORS Patented Aug. 30, 1938 UNITED STATES 4 PATENT OFFICE PRINTING TELEGRAPH SYSTEM George A. Graham and Barry W. Parmer, Long Branch, N. J.

Application May 18, 1934, Serial No. 725,968

Claims.

(Granted under the act of March amended April 30, 1928; 3'70 09G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates primarily to printing telegraphy and printing telegraph equipment, and constitutes in effect a printing telegraph system wherein exact synchronization is effected for each and every signalling impulse in a new and novel manner. However, application of a the methods and devices described herein to electromechanical systems and appliances outside the field of printing telegraphy are within the scope of the invention.

One of the main objects of this lnvention-isto synchronize each and every interval, be it spacing or marking, of the receiving mechanism with that of the transmitting mechanism, and hence to eliminate sources 'of error peculiar to previous printing telegraph practice.

In the art of printing telegraphy it is a well known fact that the basis of any system is the maintenance of satisfactory synchronism. The usual method is to make one station the controlling or time keeping station and run the controlled stations distributor slightly faster. Controlling currents are then sent once per revolution from the correcting station to correct for the phase difference which has occurred, and so accumulatio'n-of error is prevented. It is to be understood that the motors driving the distributors require more or less precise governing and the method of correction for the prevention of accumulative error takes various forms which may be summarized as follows:

l. Positively stopping the rotating brush arms or cam devices once per revolution (so-called start-stop method).

2. Uncoupling momentarily the shaft and the brush arm (Baudqt epicyclic coupling).

3. Modifying the speed of the motor (speed correction) A However, attention is invited to the fact that the known methods herein cited do not prevent the occurrence of errors within one revolution of the distributor shaft, or if solely of the governed type do not prevent error within the governing intervals because obviously an error must occur in order that the governor respond to correct that Motor governing by electrically driven tuning forks or reeds is not decisive, and motors driven by tuning forks lack power for varying loads.

the fields of printing telegraphy In the case of the start-stop" systems mis-printingoccurs dependent upon the magnitude of the error within the one revolution, Normally the governing means'of the motors are relied upon to restrict such errors within certain limits but in practice frequent failure and constant maintenance are experienced due to causes such as a difference in voltage at the respective stations, or the pitting of governor contacts and collector rings, etc.

Certain inventors have recognized the desirability of exact synchronization for each and every impulse and have attempted to obtain the desired results by means of reeds or tuning forks which were made to operate a multiplicity of con-' tacts. The contacts were then wired into various circuits to perform stepping or timing functions. Examples of this" are found in Potts, 1,151,216, and Kleinschmidt, 1,758,194, but tuning fork or reed contact arrangements are neither satisfactory nor dependable because of slow speed and low, power when used to step a shaft forward under magnet action; or'to energize relays and magnets for functional operation because of the fleeting nature of the reed or tuning fork impulse.

Also such contact operation is accompanied by contact oscillations ailecting the current value in the incident circuit. The outstanding limitations of thereed or tuning fork contact arrangement may be summarized as follows:

1. Operational speed limited by numerous magnet operations in the formation of one character. 2. Limited to controlling the power derived from the tractive effort of the magnets which is also a function of time. In magnets of any appreciable power, time is a very 'vital factor,

the relationship being:

cations in Printing Telegraph Practice by H. H. Harrisom In other words the fork or reed contact does not give anyv margin or safety factor for building up of current in the magnet. ,This is particularly true for reeds or forks vibrating above 40 vibrations per second. In our invention we employ a reed, but the reed definitely times rotational processes deriving their power from other sources than the reed, and hence power is not only constantly applied but may be of a high value. The reed then valves or escapes appreciable power constantly applied. In contradistinction to the circumstances related above this invention is predicated upon-a proper solution of the inherent disadvantages mentioned and provides a printing telegraph system wherein the receiving processes are held in step with the transmitting processes throughout all intervals. I

Accordingly another main object of this invention is to provide critical synchronizing methods for all time intervals, but at the same time permit of high speed operation, in such a manner that differences in local voltages at the various stations do not aifect the accuracy of syngression of a rotating shaft;

chronization during legitimate operation; 'and hence to provide synchronizing means which are inherently independent of voltage differences or variation;

- Another main object of this invention is to control the progressive movement of a rotating body driven by appreciable power by a constant frequency device and hence any number of other rotating bodies, similarly controlled by duplicate constant frequency devices, may be maintained in exact unison with each other and the aforementioned rotating body.

Another main object of thisinvention is to apply the principles and inherent precision of a vibrating reed to control the incremental progression of a rotating shaft, tending to rotate under the urge of appreciable power constantly applied.

Other objects will become apparent to those skilled in the art as the description proceeds.

The accompanying drawings serve to illustrate the principles involved in which:

Fig. 1 is a schematic drawing showing the basic principles of the invention as applied to the operation of two printing telegraph stations, local battery and line battery being shown at each station;

Fig. 2 is a view of the timing agent, or reed mechanism utilized to control or escape the pro- Fig. 3 is a projected view of Fig. 2;

Fig. 4 is a view showing certain keyboard controlled start-stop features;

Fig. 5 is a graphical representation of the signalling time intervals established definitely by our system: I

Fig. 6 is a schematic drawing similar to Fig. 1, except that one battery only is used at each station for the dual purpose of local and line batteries; g

Fig. 7 is a schematic drawing showing an application of the methods of signalling, synchronization, and distribution. to one particular form of selecting and printing mechanism and Fig. 8 is a schematic drawing showing theapplication of our invention to radio communication.

Reference is now made to Fig. 1, in which A and B represent two stations, some distance apart, connected together electrically by the line wire I, and the earth return 2 and 3. The details within the areas 0 and D represent conventional keyboard transmitters of the Baudot saw-toothed five-unit code type. This type is shown for convenience only, inasmuch as our invention is not restricted to the five-unit code or to any particular type of transmitter, be it keyboard, tape, etc. However, the operational characteristics of sucha keyboard transmitter are generally known and require no detailed description herein. Suffice it to say that at C, depression of any key of the keyboard, of which two are shown as 2| and 22 acts to move certain particular combinations of the sawtoothed bars, l4, l5 l6, II, or M, to the left, thus setting up a permutative arrangement of the transmitting levers 4, 6, 6, I, and 8, in relationship with the transmitting contacts 8, l0, ll, l2, and ii. In this case 32 combinations are possible which may be made to correspond to the 26 letters of the alphabet with 6 additional combinations for functional features. In addition to the five code bars a sixth or uni.- versal bar, which moves to the left upon the depression of any key of the keyboard, is. often provided for certain purposes. Also a keyboard lock is usually provided which may be cleared as the result of the completion of the printing process or may be cleared as a function of such'a cam wheel as shown at 26. It is not desired to introduce this feature in our drawings for reasons of simplicity. We will therefore assume that keyboard locking features are provided which act to lock up the permutative combinations of bars M, l6, l8, l1 and i8, and also the universal bar in and that upon the completion of one revolution of cam wheel 26 this keyboard lock is removed and all bars returned to normal for a succeeding operation. These considerations also .apply to keyboard D.

restoring features consist of a cam 21 on cam wheel 26 acting on cam push rod 26. It will then be seen-that, given that the cam wheel 26 is r0.-

' tating, the cam 21' will thrust the push rod 26 once every revolution of the cam wheel and act to restore the latch should thelatch have been released during the revolution. In the event that the latch had not been released during the revolution, the cam action would be passive. Now as shown in the drawings, this latch and restoring action on the push rod 26 serves to operate upon contact-lever 26 and hence upon contact 26, which may be summarizedas with latch locked in position during the rotation of com wheel 26 or otherwise, the contact lever 26 is in electrical continuity with contact 2!, but on the other hand should the latchhave been released by keyboard action, the contact lever 28 would be withdrawn from contact 29 throughout that revolution of the cam wheel. An enlarged view of'these some details is shown in Fig. 4.

Now let us consider the shaft 63 upon which the cam wheel 26 at station A is mounted. This shaft 43 extends from the driven side of a friction clutch as at 33 to the distributor arm 46 1 the shaft 43 and of the distributor arm 45 is as shown by the arrows. The distributor arm 45 is provided with a proper brush which sweeps the distributor segments 43, 41, 48, 49, and 50. The distributor arm and the various segments are wired as shown in the figure. The friction clutch is connected on its driving side to an electrical motor 32, which we will assume to be running under power derived from the local station battery 53, even though the actual electrical connections are not shown, being of no interest in the description. Then motor 32 drives shaft 43 through the friction clutch 33. Now the characteristic of this clutch is to. exertthrough frictional components a turning movement to shaft 43, irrespective of whether or not the shaft 43 is actually rotating. In other words, "shaft 43 may be permitted to revolve under the driving action of the clutch, or may be restrained from revolution and the'clutch allowed to slip, upon the restraining forces being greater than the forces of frictional turning movement. It remains to be shown how shaft 43 may be restrained or permitted to revolve upon occasion, and the relationship thereof with our invention. Briefly, the relationship is that the shaft 43 is permitted to progress under escapement action as controlled by an individual timing agent of definite predetermined and constant periodicity, i. e., a vibrating reed.

In the theory of vibrating bodies it is known that the fundamental frequency of vibration of a reed is-determined by the following physical properties of the reed; the material; the length: and the thickness; in the relationship:

n=84,590 approximately,

where n is the frequency of vibration, a the thickend of the reed is weighted, introduce modiflcations of the above empirical formula. However, the point to be stressed here is that the physical properties determining the fundamental frequency of vibration of a reed are readily reproducible and any desired number of reeds may be made to vibrate at a predetermined frequency. Even though it is admitted that temperature effects alter'this fundamental to a very minor degree, it is stated as a premise that any number of such reeds of equal physical properties that are released to vibrate for a limited number of cycles, let us say three complete cycles, are in absolute unison throughout those three cycles,

The above considerations are applied in our invention wherein with reference to Fig. 1, 31 designates such a reed at station A, and I08 a similar reed at station B, suitably clamped in position and mounted on the base 12 and IM respectively. At rest or start position, the reeds 31 and 103 are held locked to the left (shown dotted) under the latches of the armatures 39 and H of start-stop magnets 4| and I I2. In the stressed position shown potential energy is stored in these reeds and/upon being released the reeds tend to vibrate with an initial amplitude as represented by the dotted views to the right. Obviously this process is repeated with a decrement dependent upon the work imposed on the reed and the mass of the counterweight. In each half cycle of vibration the reeds are made to move escapement yokes 34 and I03 thus alternately escaping the pins of hubs 42 and I01.

The reed, start-stop features, escapement, driven shaft, clutch, and drive shaft, are shown more clearly in Figs. 2 and 3. with reference to Fig. 2, the reed is 31, weight 203, escapement driving link 35, escapement pawl yoke 34, bearing shaft 36, bearin .trunnion 20l, reed clamp 202, base 12, escapement pawls 34a and 34b, escapement pins 38 and 38a, escapement hub 42,

' driven shaft 43, driven clutch member 33a, driving clutch member 331), and drive shaft 203. The phanton positions 31a and 31b denote the limiting positions of the reed in vibration, wherein position 31a is also the starting and stopping position. The start-stop magnet is 4|, magnet pole 208, armature 205, armature lever 39, pivot 204, retractile spring 40, start-stop latch 201, latch spring 286, and electrical conductors 62 and 83 connecting the windings of magnet H to a source of electrical power. The above details, with the exception of the magnet and clutch details, are shown in another view by Fig. 3, in which note escapement pins 381), 38c, 38d, and 38e. Let us now consider the sequence of events which occur in "a typical example of operation from the instant that the reed is released by the magnet. We will assume that the 'magnet 4| is energized; the armature latch is restraining the reed 31 in position 31a; the escapement pawl 34b is interposed under pin 38 and that shaft 43 and the driven clutch side 33a are motionless; and the drive shaft 209 is rotating in the direction indicated by the arrow hence the driving clutch side 33b is slipping with respect to the driven side 33a. Upon de-energizing magnet 4|, the armature latch 201 is disengaged from the reed by retractile spring 40 action. The reed moves over to position 31!) carrying the escapement yoke 34 along with it by virtue of the link coupling 35. Accordingly pawl 34b is removed from beneath pin 38 and-shaft 43 is permitted to revolve as indicated under the compulsion of the friction clutch. However, the escapement yoke 34 has now interposed pawl 34a to interfere with the revolution of shaft 43 beyond pin 38a. The shaft has stepped forward one pin position and is again motionless. Due to natural vibratory phenomenon, the reed now returns to position 31a moving the escapement yoke 34 back to the initial position thereby removing pawl 34a from under pin 38a and interposing pawl 34b in the path of the oncoming pin 38b. The shaft once again progresses to the position of engagement of pin 38b and pawl 34b. Without undue repetition it should be apparent that in this wise the shaft is alternately permitted to progress under reed escapement any desired number of times. In our example we permit the shaft to escape six times and stop the reed in the initial position 31a upon the completion of the sixth half cycle (three complete cycles of reed vibration). The stopping of the reed is performed as a properly timed function of the energization of the startstop magnet through the operation of the armature and attached latch. It will beobserved that the latch is so constructed that the reed may pass under the latch and lock in position 31a after the scribed. It is to be understood that these events occur at relatively high speeds, in fact, in certain models constructed the reed was made to vibrate at 40 cycles per second, which in terms of escaped pins (and hence as will be shown later in terms of transmitting distributor spacing-marking intervals) permits printing telegraph transmission or reception speeds of approximately 130 words per minute; Accordingly an ample margin is provided for si'ich commercial speeds as 65 words per minute.

In summation of the above it has been shown how the rotary progression of a shaft operating under appreciable power may be accurately timed for predetermined intervals by means of such a constant frequency device as a reed, and that such timing is independent of the speed of shaft 209 (i. e. independent of the speed, and hence of any variation of the value of the impressed E. M. F. of the-motor driving shaft 209), the only requirement in this respect being that shaft 203 rotate above a given rate. Obviously the presentation of pins to the escapement must be at some speed above that of the reed controlled escapement operation. This feature entirely eliminates the necessity for a governed mo- .tor, and any motor which operates above a given rate may be used.

In the design and development of the. reed and escapement certain additional features were incorporated which requireexplanation as a basis for further understanding. Each escapement pin 38, 30a, 38b, 38c, 30d has that corner of disengagement with the escapement pawls 34a and 34b very slightly roundedto facilitate smooth disengagement. Care and some experience is required in this construction to obtain the desired results .and to obviate any tendency of the escapement driving the reed, rather than the reed driving the escapement yoke. However, pin 38a is provided with a well rounded corner for the particular purpose of restoring the reed to the initial position under the latch. Consider that after the reed has been released and moved over the position 3122, upon return to position 31a-will experience a decrement in amplitude. A corresponding decrement afiects the amplitude of each in which case the r successive vibration evenalthough in our example we assumed that only six half pycles were performed, and hence the decrement is small but exists due to natural law and the fact that the reed assisted by the weight 203 has been required to perform the work of moving the escapement yoke. At the end of the sixth vibration the reed may not entirely seat behind latch 201'. Pin 38c by virtue of the rofiinded'corner, and of a certain out of line position, assists in this process and imparts suflicient energy to the reed in the last half cycle to fully pass the reed behind the latch. This'feature should be borne in mind because it will be used later in our description as the method of moving the reed from inoperative position 31 to start position 31a behind the latch. In printing telegraph practic it may be desired to start a certain number of tions from inactive status ds will be in position 31. It will be seen that certain devices may readily be incorporated to act to start the motors and hence shafts similar to 43 at allstations revolving. Pins 38. 38a, 38b, 38c, and 38d will pass through the then centrally located escapement yoke 34 and the pawls 34a and 34b, but pin 30c will present the rounded corner to .the corner of pawl 34a and thrust pawl 34a, link 35, and the reed to the.

We are now in start position at all cance of pin 38c and pawl 34a because full en-' gagement of pawl 34a with the under surface of pin 38a is provided in position 3112 where the pawl is fully under the pin irrespective'of the rounded corner. With regard to the clutch certain additional features not shown in the drawings are incorporated in the actual models. For

example spring tension is provided through ball maining elements of Fig. 1. 52 and I2I are cong ventional line relays capable of operational speeds to printing telegraphy. These relays are equipped with the armatures and contacts 55-56 and I24-I25 respectively. Armature retractile springs are shown but magnetic bias may be used if desired. Each station A and B is equipped with local or station battery at 53 and I22. The voltage and capacity of these batteries are determined by the. characteristics of the local circuits and the load considerations. The wires 58-59 and i21--I20 indicate connections to printing equipment. Now many'forms or types of printers may i be connected to these wires and operated with complete success. We will hereinafter show one specific type and discuss still another type as applied to our processes of synchronization but at this point suffice it to say that printing equipment is connected to wires 58-59 and I21-I28. The batteries 54-,and I23 are line batteries (furnish current to the line and equipment in series with the line), and are poled to aid each other. The voltage of these batteries depends upon the resistance of the line circuit and upon the value.

of current required for operation of the linerelays.

Let us recapitulate: Fig. 1 shows two transmitting-receiving printing telegraph stations located. some-distance apart and generally designated as A and B, respectively. The equipment at one station isthe counterpart of the equipment-at the other station. C and Dare keyboard transmitters, equipped with start-stop latches. 32 and IM are distributor motors. Numerals 43 and I09 designate intermediate shafts the progression of which is dependent, for each and every interval, upon the performance of the reeds 31 and I06. The reeds are released or restored by elements previously described, i. e.,

magnets 4| and H2, and certain pins of the esgcapement hubs 42 and I01. Numerals 44 and H3.

denote transmitting distributors, the receiving distributors being shown later in Fig. 7. Each station is provided with proper battery and with line relays. The relays function to operate printing equipment (not shown) through receiving distributors; electrical or cam (also not shown). The various elements comprising azstation are wired as shown schematically in the figure. The two stati us are connected together bya line wire and eart return. This circuit may be complete metallic, simplex, or other suitable arrangement so long as the stationsare connected together electrically.

A typical example of the operation of the various elements shown in Fig. 1 may now be considered. We will assume that keyboard locking and clearing features are installed as described above in the discussion of the keyboard; motors Y32 and III! are running; reeds31 and I05 are a point.

. hence relays 52 held under the latches in the left dotted position, and hence shafts 43 and I09 are motionless because with reeds to the left the escapement yokes 34 and I03 prevent the pertinent pins from escaping; the distributor arms 45 and H4 are at rest in the position shown and in contact with distributor segments and I20 respectively: and that 'relay armatures andcontacts 55-56 and I24-I25 are closed. Let us trace the circuits to verify these assumptions. Starting from battery 54 at station A, the line circuit is wire 10, contact 29, contact lever 28, wire 66, wire 6I, relay 52, line wire I; and at station B line wire I, relay I2I, wire I30, wire I33, contact lever91, contact 98,.wire I39, battery ground 3 and by ground 2 and wire II return to battery 54 at station A. The line circuit is closed and I2I are energized and their contact combinations 55-56 and I24-I25 are closed. The contacts however concern the local circuits at each station. The local circuit at station A provides two branches; battery 53, wire 51, contact 56, armature 55, wire 62, magnet 4|, wire 63, distributor segment 5I, distributor arm 45, wire 6|, wire 60, and return to battery 53, this circuit constitutes the reed holding and releasing means; battery 53, wire 51, contact 56, armature 55, wire 59 to printer equipment (either a distributor and associated printing devices, or a receiving magnet and associated printing devices), from printing equipment by wire 58 return to battery 53. The. corresponding local circuits at station B are: battery I22, wire I28, contact I25, armature I24, wire I3I, magnet II2,wire I32, distributor segment I20, distributor arm 4, wire I30, wire I29, and return to battery I22; battery I22, wire I26, contact I25, armature I24, wire I28 to printer equipment, return by wire I21 to 'battery I22.

The operator at either station may now manipulate his keyboard. Assume that the operator at station A depresses key 22. All keys are on the common pivot 20. The Baudot sawtoothed bars I5, l1, and I8 will then be thrust to the left and locked, closing levers 5, 1 and 8. against contacts I0, I2, and I3. The universal bar I9 has also been moved to the left at the same time thereby thrusting the trigger 30 to the left, and locked there by the keyboard lock. The trigger 30 is so constructed as to exercise cam action at its extremity on contact lever 28 and hence the contact lever is moved out of engagement with contact 29 opening the circuit at that opened at contact 29. The first result caused by the opening of the line circuit is the de-energiza-.

tion of relays 52 and I2I causing these relays to open their contact combinations 55-56 and I24-I25. These contacts open the circuits to magnet M and magnet II2 respectively and the reeds 31 and'l06 are released and swing toward the right dotted position. The reeds 31 and I06 move the escapement yokes 34 and I03 also to the right thereby permitting pins 36 and I08 to escape and shafts 43 and I09 to revolve. The initial movement of shafts 43 and I09 serves to remove cams 21 and 96 from thrust on push rods 25 and 94. However there is this notable difference. At station A keyboard actuation has tripped trigger 30 while at station B the trigger has not been tripped. The difference is in effect that the opening of contact 29 at station A by keyboard action is further to be held open until the cam 21 completes one revolution and acts to restore the latch 23 even although key 22 may I23, wire I40 to Accordingly the line circuit has been.

have been released meanwhile. 0n the other hand, at station Bcontact lever 91 and contact 98 remain closed because the'latch 92 is held by trigger 99 and hence thepush rod 94 remains in its initial position even although the cam 96 has moved out of engagement. Hence the keyboard transmitting contacts at station B will be shorted out during this revolution of cam wheel 95, which definitely allocates the signalling functions to station A and holds station B receptive to that signalling. The reed 31 has now moved over to the right dotted position and has moved the escapement yoke 34 to the right also by virtue of the connection of link 35, hence the left pawl of the escapement yoke is in position to stop the next pin behind pin 38. Accordingly the shaft 43 is only permitted to revolve to that pinposition. The reed I06 at station B has performed in an identical manner with respect to shaft I09. In these processes the distributor arms 45 and H4 have moved from segments 5I and I20 respectively to segments 46 and I I5 where they are held until the reeds 31 and I06 again clear the escapement. It is desired to emphasize the fact that the relative speed of. shaft 43 with respect to shaft I09 has nothing to do with the signaling time interval that the distributor arms contact segments 46 and H5, this time interval being definitely a function of the two reeds. Now we have assumed that bar I4 was not moved and therefore lever 4 is open with respect to contact 9. This interval then is a spacing interval during which the line circuit is open at contact 9 and is so translated by the line relays 52 and I2I and hence contact combinations 55-56 and I24-I25, and in turn by the printers selecting mechanism connected to wires 58-59 and I21-I20. The reeds 31 and I06 now return to the left dotted positions and in so doing permit by escapement action shafts 43 and I09 and distributor arms 45 and H4 to rotate to the next escapement pin position which coincides in angular displacement with the centers of segments 41 and H6. We have assumed that bar I5 was moved to the left closing lever 5 and contact I0 in marking position. Marking current now flows from battery 54, wire 10, lever 5, contact I0, wire 68, segment 41, distributor arm 45, wire 6I, relay 52, wire I, relay I2I, wire I30, wire I33, contact lever 91, contact 98, wire I39, battery I23, wire I40, ground 3, ground '2, wire II return to battery 54. This interval then is a marking interval and is so translated by the line relays 52 and I2I by means of the contact combinations 55-56 and I24--I25 to act accordingly upon the printers selecting mechanism connected to wires 58-59 and I21-I28. The reeds 31 and I06 now swing to the right dotted positions on the first half of the second cycle and in so doing permit shafts 43 and I09 to revolve to the next escapement pin position thus progressing the distributor arms 45 and I I4 to the centers of segments 48 and III. The assumption was that bar I6 was not moved ,and therefore lever 6 is open with respect to contact II. This interval constitutes a, spacing interval during which the line circuit is open at contact II and is so translated by relays 52 and I2I and in turn through the relay contacts by the printers selectng mechanism connected to wires 58-59 and 'I 21-I28. The reeds 31 and I06 now return to and H8. We have assumed that bar I1 was moved to the left closing lever -'I and'contact I2 in marking position. Marking current now flows from battery 54, wire 10, level 1, contact I2, wire 65, segment 49, distributor arm 45, wire 6|,relay 52, wire I, relay I2I, wire I30, wire I33, contact lever 91, contact 98, wire I39, battery I23, wire I40, ground 3, ground 2, wire 1! return to battery 54. This interval then is a marking interval and is so translated by the line relays 52 and I2I by means-of the contact combinations 55-56 and I24I25 to act accordingly upon the printers selecting mechanism connected to wires 5859 and I21-I28. The reeds 31 and iBnow swing to the right dotted position on the first half of the third and last cycle and in so doing permit shafts 43 and I09 torevolve to the next escapement pin position and accordingly progress the distributor arms 45 and I to the centers of. segments 50 and H9. We have assumed that bar I8 was moved to the left closing lever 8 and contact I3'in marking position. Marking current again flows as described above for bar I1 and segment 49 except that now the path is by wire 10, lever 8, contact I3, wire 64, segment 50, and the distributor arm 45 to line by wire 9|, relay 52, line wire I.

As before this interval'is a marking interval and is so translated by the line relays 52 and I28 by means of the contact combinations 5556 and I24-I25 to act accordingly upon the printers selecting mechanism connected to wires 5859 and I21--I28. The reeds 31and I06 now return to the left dotted position on the second half of the third and last cycle and in so. doing escape the sixth consecutive escapement pins on the escapement hubs 42 and I01. It will be recalled that the sixthescapement pin, detail 38a of Fig. 3, provided a rounded corner to facilitate the restoration of. the reed beneath thestart-stop latch. Consider this impulse to have been imparted to reeds 31 and I06 as the sixth pins of. hubs 42 and I01 are escaped. Shafts43 and 809 revolve to the initial pin positions 38 and I08 and the distributor arms 45 and H4 revolve to the center of the initial segments I and I20. Also cams 21 and 96 have completed one revolution and are again in engagement with push rods 25 and 94. As described above thecam 96 has no efiect on push rod 94 because that push rod had not been triggered out of initial position but the push rod 25 having been triggered out of initial position is now restored to that position by cam 21- and at the same time, or slightly prior thereto, the

- keyboard lock is released and bar I9 and all other bars restored to initial position. (See description of keyboard lock above.) The restoration of push rod 25 and bar I9 to initial positions results in engaging latch 23 under trigger 30 and restoring contact'lever 28 to contact 29. These occurrences are properly timed so that at the instant the distributor' arms 45 and H4 make contact with segments 5| and I the initial circuits described at the start of this example are set up, or restored,

to operate magnets 4I and H2 and hence restrain the reeds from further vibration. With respect to time, the armature latching of 39 and H0 are actually inposition to catch the reeds slightly before the reeds passunder the l'atches.' Hence the latch construction. Also it will be appreciated that coincident with this time period the actual printing processes of the selected character or function occurs with respect to the printing equipment connected to wires 58-59 and n l-I28.

In the above example.v and in fact in the dis.-

' which 45 and I42 are connected trolled shaft 43 at station A. mitting distributor face and closure shown by Fig. 1, it will have been noted that receiving distributors have not been shown or discussed at length. Fig. 1' shows-distributors which are employed as transmitting distributors because whereas. operation from'station A was assumed, during the process the signalling segments of station B were automatically shorted out to maintain the required line continuity. Had operation from station B been assumed the same arrangements would have existed at station A. It has. been the intention of the specification up to this point to build up a background sufilcient to serve the investigator or reader as proper material for the required extension of. our invention'to receiving distributors as well as transmitting distributors. Even at this point those skilled in the artwill doubtless have appreciated that proper continuation of shafts I3 and I09 would serve as agents upon which either receiving distributors or cam selectors could well be operated in harmony with the theory of the invention. These matters will bedisclosed at length hereinafter.

' Before continuing however let us examine the line current characteristics (or signalling characteristics) of our invention. Reference is made to Fig.5. This figure represents graphically the time intervals established definitely by the reed, escapement action upon the transmitting distributor for each and every spacing and marking interval in contradistinction to previous systerns. In our system the time elements b are predeterminable, equal, and for a 40,-cycle reed represent 1/80 of a second. In certain previous systems the time element a is accurately established but the elements bvary greatly with respect to each other, contingent upon many indeance. (in the other hand, Fig. 6 shows-the connections by means of which one battery only may be used at each station for the dual-pur pose of line and local battery. This figure then may be considered as supplementing Fig. 1 and the theory of operation is sufiiciently parallel to that previously given for Fig. 1 as to not warrant a separate description.

We will now continue with the primary consideration of describing our methods of signalling, synchronization and distribution, as applied to one particular form of printer conceived by us, although many other types may be employed.

Reference is madeto Fig. 7. In this figure A and 13 generally represent two stations, some distance apart, connected together electrically by the line wire I, and the earth return 2 and 3. C and D are keyboard transmitters. 44 is the transmitting distributor face and MI is the receiving distributor face, the distributor arms of to the reed con- II3 is the trans- I12 is the receiving distributor face, the distributor arms ofwhich [I4 and I13 are connected to the reed controlled shaft I09 at station B. The reed start-stop magnets are 4| and H2 and the line relays are 52 and I respectively. The line batteries are 54 and I23. and the local station batteries are 53 and I22. The elements directly above E and F comprise the basic features of printing units. The printing function may be by motor driven cams or by magnet action. In our case we show a magnet printing type. It will be sufllcient to describe the printer at station A. The selector or translator is of the well known Baudot five-slotted bar type, the selector bars being I56, I51, I56, I53, and I60 positioned properly under the pivoted I6I, stunt bars I62 and I63. Obviously there are as many stunt bars as there are characters to be printed or functions to be performed. Each selector bar is held normally to the left, but under magnet action I65, I06, I61, I68, and I69 are moved to the right in accordance with the permutations of the Baudot code. In any of these permutative arrangements one and only one stunt bar may fall in the slots and hence one character or function be presented for printing or performance. The printing magnet is shown at I 64. In our use of these elements a printing and clearing feature is incorporated at I10, the action being that the contacts are held open so long as none of the stunt bars have fallen in the slots but as soon as a stunt bar falls fully in the slots contact is made through the agency of a universal bar shown dotted and the magnet is receptive to the printing pulse. After the printing stroke and in the return motion of the armature of magnet I64, the selected stunt bar is returned to normal by action through the universal bar.

Let us consider an example of operation from station A. We will assume that motors 32 and I III are running; the line is energized, battery current flowing from 54, wire .10, contact 29, contact lever 20, wire 66, wire GI, relay 52, wire I, relay I2I, wire I30, wire I33, contact lever 91, contact 98, wire I39, battery I23, wire I40, ground 3, ground 2, return by wire II; hence relays 52 and I2! are energized and their contact combinations closed by virtue of which the reed magnets are also energized and the reeds 31 and I06 held in the left dotted position, the circuit in this respect at station A being battery 53, wire 51, contact 56, armature 55, wire 02, magnet 4|, wire 63, distributor segments'5I, distributor arm 45, wire BI, wire 60, return to battery 53, and a sim= ilar circuit at station 13, and shafts 03 and I03 are motionless by virtue of the reed escapement position.

The operator at station A strikes, let us say, the key 2| which is in our-representation of the five unit code, bar I4 marking position, bar I5 spacing position, bar I6 marking position, bar I1 spacing position, bar I8 marking position, and the universal bar I9 marking as for every key. I The depression of the key has opened contact lever 28 and contact 29 at station A, and hence has opened the line circuit. The contact lever 91 and contact 98 at station B remain closed as shown. The opening of the line circuit at sta-- tion A results in de-energizing relays 62 and I2I and by the contacts opening of these relays deenergizing magnets 4| and IE2 which in turn release the reeds for the performance of the first half of the first cycle. Thedistributor arms 45 and I42 at station A and H4 and I13 at station B move forward to segments 46, I43, I I5, and I14 respectively where all are held by reeds escapements for exactly the same period of time. Had either stations distributor arm combination arrived at this stop position ahead of the distributor arm combination at the other station the signalling time interval would not have been affected in the least degree because the reeds control the release of both distributor arm combinations. During this interval marking current flows from battery 54, wire 10, keyboard lever 4, contact 3, wire 69, segment 46, arm 45, wire 6|, relay 52, wire I, relay I2I, wire I30, wire I33, contact lever 91, contact 38, wire I39, battery I23, wire I40, ground 3, ground 2, wire 1I, return to battery 54. So much for the line signalling circuit. At station A current flows from battery 53, wire 51, contact I55, selector magnet I65, wire I49, segment I43. arm I42, wire 50, return to battery 53. Selector bar I66 has been moved to the right and is mechanically locked in that position, the look not to be released until after the printing stroke or functional operation has been completed. At station B the selector bar I86 has also been moved to the right in an identical manner, the circuit being from battery I22, wire I26, contact I25, armature I24, wire I20, common wire 200, magnet I95, wire I00, segment I14, arm I13, wire I21, return to battery I22. Without unduly prolong- 56, armature 55, wire 59, common wire ing the matter, it is believed that the succeeding spacing and marking processes have been made clear throughout the remaining five half cycles of reed vibration to the final stopping of the reed and the performance of the printing stroke at each station when the arms I42 and I13 have returned to segments I49 and I19, after which contacts I10 and III are automatically opened by universal bar action in conjunction with the return to normal of the printing magnet armature. The very vital point to be stressed is that all transmission and reception time intervals have been definitely established by the independent agency of the reeds, without recourse to any contacts on the reeds or to any contacts operated by the reeds.

It may readily be seen that the application of our principles to radio communication rather than to wire communication is but a question of transmission medium. However, in the event that such connections are not quite clear, the stations as shown in Fig. 'l are connected for radio transmission and reception as shown in Fig. 8 without going into any of the details of transmitter or receiver construction. The relays 52 and I2I have been given the same detail numbers for identification purposes. Additional contacts have been added to relay 52. Station A has been taken as the transmitting station and station B as the receiving station.

.Changes and modifications are contemplated within the scope of the invention 'as defined by v the appended claims:

We claim: 1. In a printing telegraph system, comprising a.

plurality of stations each of which is provided,

means; and a constant frequency device including a vibrating reed for positively actuating and controlling the escapement action of said mechanism and independently of external timing devices.

2. In a transmitting-receiving printing telegraph system, comprising a plurality of stations, eachstation being provided with means for the transmission and reception of permutative code' combinations of impulse conditions; means at each station for maintaining all processes of reception in synchronous relation with those of transmission, comprising a phase controlled escapement mechanism, said mechanism comprisactuating and timing the escapement action 01.

said yoke.

3. In a high speed signalling system, comprising means for sending and receiving code combinations of signalling conditions, means for equalizing the time intervals of an equal unit code, comprising an escapement mechanism; and a constant frequency device, including a vibrating reed of predetermined periodicity for controlling the action of said mechanism in accordance with the frequency of said reed and independently of external timing agencies.

' 4. In a system of printing telegraphy, comprising rotary members for controlling the processes of selection and distribution between local and distant stations of the system, and including power sources for driving said members; means for synchronizing the action of the members of one station with those of another station, comprising an escapement mechanism operative to regulate the transmission of motion to said members in equalized intervals and independently of the speed of said power sources; and matched vibrating reeds at said stations for positively actuating and timing said mechanisms.

5. In a system of electrical communication, means for controlling theprocesses of transmitting and receiving signalling impulses at one station from any one of a plurality of other stations, comprising duplicate escapements at each station; vibrating reeds having matched periodicityand functioning independently of other timing agencies for positively timing the action of the. escapements; a prime mover, and differential means for transmitting motion therefrom to each escapement, comprising a slipping clutch to permit the escapements to operate in synchronism and independently of the speed of l the prime mover;

6. In a system of printing telegraphy, comprising rotary elements for controlling the processes of selection and distribution between local and distant stations of the system; means for synchronizing the action of said elements of one station with those of another station, comprising an escapement: a vibrating reed of predetermined constant pe iodicity at each station for timing and actuating said escapement; power sources and diflerential means for coupling the same with each escapement whereby said escapements are driven in synchronism under the positive control of said reeds and independently of the speed of said sources.

7. In a printing telegraph system comprising transmitting means at a local station for establishing electrical sequences aifecting receiving means at a distant station; and means to maintain the sequences in synchronism, comprising an escapement mechanism at each station and matched vibrating elements of predetermined constant periodicity for controlling said mechanism; and means for starting and stopping the vibration of said elements in predetermined operative cycles.

8. In a printing telegraph system, comprising a plurality of transmitting and receiving stations, each station being provided with means for the transmission and reception of electrical impulses; means for establishing the sequence of said impulses, and including a rotatable shaft at each station; and means carried by each shaft to maintain thesequences of a transmitting station in phase with the sequences of a receiving station, comprising an escapementmechanism and a vibrating reed for controlling said mechanism independently of the speed of rotation of said shaft.

9. In a printing telegraph system, comprising a plurality of transmitting and receiving stations, each station being provided with means for the transmission and reception of signalling impulses; and means for the establishment of definite and equal periodicity of each signalling interval, comprising an escapement mechanism,

said mechanism including a rotatable body provided with movement arresting means, an escapement yoke for operating the arresting means;-and a vibrating element having a predetermined periodicity to actuate said yoke for positively controlling the escapement action of said mechanism.

10. In a printing telegraph system, comprising a plurality of sending-receiving stations, each station being provided with means forthe transmission and reception of electrical impulses; and means at each station for maintaining all receiving processes in exact synchronism with the transmitting processes, comprising an escapement mechanism; and a constant frequency timing element including a vibrating reed for posi tively controlling the escapement action of said mechanism independently of voltage variations in the system,

l1.- In a printing telegraph system, comprising a plurality of stations, each station being provided with means for the transmission and reception of signalling impulses; an escapement mechanism at each station to effect the phase control of said impulses, comprising a rotating member mechanical means for operating said membe including a driving shaft and a driven shaft carrying said member; and means comprising a vibrating reed operative with the escapement mechanism to maintain a synchronous relation between the rotating members of each station in predetermined incremental progression all-rd tindependently of the speed of the driving s at 12. In a printing telegraph system, comprising a plurality of stations; means at each station for the transmission and reception of signalling impulses, including transmitting and receiving distributors; means for maintaining synchronous operation of said distributors comprising an escapement for controlling the predetermined incremental progression of each distributor; and a vibrating reed for positively actuating and controlling the escapement.

13. In signalling systems, comprising elements mounted forrotation on intermediate driven shafts differentially coupled to the driving shafts, said driving shafts being operated at predetermined speeds; means for controlling the rotation tively controlling said escapement independently of external timing agencies. I

14. In a system of printing telegraphy, comprising a plurality of stations, each station being provided with means for the transmission and reception of signalling impulses; means for synv chronizing all time intervals of transmission and reception between said stations, said means including elements mounted for rotation on intermediate driven shafts; driving means for said shafts; and means at each station for controlling the rotation of said driven shafts at a definite progression in relation to unit time and independently or the speed of said driving means, comprising an escapement mechanism; and a vibratoryelement of predetermined periodicity at each station for timing said escapement independently of external timing agencies.

15. In a mechanical transmission system, comprising rotating elements mounted on driving and driven shafts, said shafts being coupled for differential movement relative to one another; and means for controlling the progression of the driven shaft independently of the speed of ,the driving shaft, comprising an escapement mechanism; and a vibrating element of predetermined periodicity for positively actuating and timing said mechanism.

.16. In a system of synchronizing the speed of rotating bodies, means for determining the progression of said bodies with respect to unit time, comprising an escapement operative with each body; and means ior controlling each escapement, comprising matched vibrating reeds of predetermined periodicity ior positively actuating and timing the escapements.

17. In a printing telegraph system, comprising rotating bodies driven from separate sources of varying power; means for synchronizing the speed of rotation of said bodies independently of the speed and power of said sources, comprising an escapement mechanism operative with each body; and a constant frequency timing device, including a vibrating reed for positively controlling the escapement action of each mechanism.

18. In a printing telegraph distribution system, comprising local and distant transmitting and receiving distributors, said distributors being driven from separate sources of power; means for maintaining synchronous progressive electrical and mechanically controlled operation of said distributors independently of the speed and power variation of said sources, comprising an escapement mechanism coordinated with each distributor; and means for positively actuating and timing each mechanism; including a vibrating reed having a predetermined periodicity.

19. In aprinting telegraph system, comprising transmitting means at a local station for establishing electrical sequences afiecting receiving means at a distant station; means for maintaining the sequences of each station in synchrnnism, comprising an escapement mechanism; a timing device comprising a vibrating reed of predetermined constant periodicity for positively controlling the escapement action of said mechanism; and means dependent upon the action of said device for starting and stopping the cycle of said sequences.

20. In a printing telegraph system, comprising means for the transmission of electrical impulses, said means including a rotating body; means for controlling the incremental progression of said body, comprising an escapement mechanism; a vibrating reed for tiining said escapement mechanism through an operative cycle; a latch for retaining the reed against vibration; a magnet for operatin; the latch; an electrical circuit including said magnet;- means responsive to a starting impulse to de-energize the magnet whereby the latch is released; and means in said circuit acting under the control of the escapement mechanism upon the completion of an operative cycle to energize the magnet whereby the latch is operated to lock the reed against further vibration.-

21. In a printing telegraph system, comprising distributors; means controlled by saiddistributors for transmitting and receiving code combinations of signalling conditions; a mechanism forcontrolling the incremental progression of said distributors, including a rotary member provided with escapement pins; a vibrating reed of predetermined periodicity for timing an operative cycle of said mechanism; means to control the escapement action, comprising escapement pawls actuated by the vibrating reed and alternately engaging said pins; a magnet having a spring retracted armature, and a latch carried by saidarmature for locking said reed against movement when the magnet is energized; an electrical circuit including said magnet; means responsive to a starting impulse to .open said circuit whereby the magnet is de-energized and the latch is released to start the vibration of the reed; means in the aforesaid circuit acting under the control of the escapement mechanism upon the completion of an' operative cycle to energize said magnet whereby the latch is brought into position to lock the reed, one of said pins being provided with means to impart an extra thrust to one of said pawls whereby the reed is swung into locking engagement at the end of said cycle.

22. A printing telegraph system, including rotating bodies driven from separate sources of varying power; means for synchronizing the speed of rotation of said bodies independently of the speed and power of said sources, said means including an escapement mechanism; means for controlling said mechanism including a vibratory reed; means including a magnet for normally holding said reed from vibration; a circuit system including said magnet; and means acting in response to electrical impulses transmitted through said circuit system to operate said magnet whereby said reed is released to escape said mechanism through an operative cycle.

23. A printing telegraph system comprising a plurality of stations, each station being provided with means for the transmission and reception of electrical impulses, and said means including rotating bodies; means for determining the progression of said bodies with respect to unit time comprising a step by step mechanism; means for controlling said mechanism including a vibratory reed; means including a magnet for normally holding said reed from vibration; an electrical circuit system-including said magnet; and means for operating said magnet whereby said reed is released to escape said mechanism in code groups in response to impulses transmitted through said circuit system. 4 p

24. In a system of machine or automatic tele raphy, comprising members in rotary progression for distributing, transmitting and receiving processes between local and distant stations of the system, and including distributor segments and stopstart segments coordinated with said members at each station; power sources for driving said members; means for maintaining step by step unison for each and every distributor transmitting segment as well as stop-start segments of one station with each and every distributor receiving segment as well as stop-start segments of another v matched vibrating reeds at said stations positively actuating and timing said mechanisms.

25. In a system of. printing or machine teleg= raphy, comprising members in rotation for distributing sending and receiving processes between local and distant oillces of the system, and includ- 'ing power sources for driving said members;

means formaintaining step by step unison of the sending distributor at one office with the receiving distributor at another ofllce for each and every signaling interval whether marking or spacing in equalized steps with respect to time, comprising an escapement mechanismoperative to control the progression of rotation of said members in, equalized intervals and independently of the rate of rotation of said power sources; and matched vibrating reeds of predeterminable periodicity at said stations for positively said mechanisms.

" GEORGE A. GRAHAM.

HARRY W. PARMER.

actuating and timing I

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