US2025778A - Telegraph typewriter system and apparatus - Google Patents

Description

Dec. 31, 1935. w, RQ Er AL 2,025,778

TELEGRAPH TYPEWRITER SYSTEM AND APPARATUS Original Filed Sept. 1 1, 1925 6 Sheets-'Sheet 1 TAM- SML.

' ATTORNEY Dec. 3l, 1935. w. c. ROE ET AL TELEGRAPH TYPEWRITER SYSTEM .AND APPARATUS Original Filed Sept. l1. 1926 6 Sheets-Sheet l2 32 sla 5H Dec. 31, 1935. i W;` Q RCE Er AL 2,025,778

TELEGRAPH TYPEWRITER SYSTEM AND APPARATUS Original Filed Sept. `1l, 1926 6 Sheets-Sheei 3 ma@ ATTORNEY Dec.` 371', 1935. w. c. ROE Er AL 2,025,778

TELEGRAPH TYPEWRITER SYSTEM AND APPARATUS Original Filed Sept. ll. 1926 6 Sheets-Sheet 4 an. au gow v as .35

so f ao i 296, yf 296 i 'I as? l 306 au? El aus M INVENTORS www W "k"- ATTORNEY Dec. 31, 1935. w. c. Rol-2 ET AL TELEGRAPH TYPEWRITER SYSTEM AND APPARATUS Original Filed Sept. ll. 1926 6 Sheets-Sheet 5 Q w u. 3 3 C G 2 a a 5 5 u. u.. l am w s au o t m W V i Bw ,zsax w Maz, @m1 f. l ,o 2 3 s m 5 INVENTORS Tl-l ATTORNEY.

Dec. 3l, '1935. w C, ROE ET AL TELEGRAPH TYPEWRITER SYSTEM AND APPARATUSy 6 Sheets-Sheet 6 Original Filed Sept. 11. 1926 mvENToRs ym mass- Eig ATTORNEY.

Patented Dec. 3l, 1935 UNITED STATES TELEGRAPH TYPEWRITER SYSTEM AND APPARATUS William C. Roe and Fred J. Heavens, Elyria, Ohio, assignors, by mesne assignments, to Printel Communication Systems, Inc., New York, N. Y., a corporation of New York Application September 11, 1926, Serial No. 134,882 Renewed Marchl 28, 1934 39 Claims.

Our invention relates to telegraph typewriter systems and apparatus therefor, of the general type wherein a telegraphic message transmitted from a station, may be automatically received at a distant station and reproduced in printed characters thereat.

Among the objects of our invention are the following:

To accomplish the full automatic and un-attended operation of receiving.

To accomplish the printing of the message at the distant station under the control of a sending machine in a system where synchronism between sending and receiving machines, as the term is used, is substantially unnecessary.

To accomplish two-way' printing telegraphic service employing readily portable machines.

To provide a system and apparatus therefor capable of operating by power which may be taken from commercial electrical power mains.

To accomplish the operation of the apparatus of the system under electrical control and to prevent the use of power of any kind when the machines are not in use.

To accomplish the telegraphic function employing line currents of small strength.

To accomplish two-way communication through the use of suitable control switches at the stations and to accomplish the automatic stopping of each of the machines if the operator neglects to do so.

Io accomplish the transmission of telegraphic messages in a system wherein printed copies of the messages may be automatically produced at both the-transmitting and receiving stations.

To provide apparatus for "the transmission of such messages which may be operated under the control of a keyboard such as is commonly used for ordinary typewriters, whereby no special training is required for its operation.

To provide apparatus sufcient for all transmitting and receiving purposes at each station but which shall be light in weight.

To accomplish the continuous feeding of paper to the printing mechanism and to permit the loading of both sending and receiving machines with sufficient paper for a considerable period of operation.

To provide an electrical system capable of accomplishing the desired telegraphic and printing functions but wherein no current will be required to flow over the line intermediate the stations at any time, except when the telegraph impulses are transmitted thereover.

To accomplish the telegraphic and printing functions desired in a system wherein the variation of voltage and frequency allowable in commercial electrical power plants, from which the operating current for the system may be taken, will have no substantial effect in reducing the accuracy or efficiency of the machine.

To accomplish the selection, starting and stopping of a given one or more machines on a common line circuit.

To accomplish the above results in a. system employing machines of unit construction wherein all units thereof are interchangeable with like units of the other machines.

To accomplish a satisfactory speed of message transmission and reception, with a minimum of wear of the mechanical parts of the machines.

Other objects of our invention and the invention itself will be apparent from the following description of an embodiment thereof, and in which description reference will be had to the accompanying drawings, illustrating, most diagrammatically, the said embodiment.

Referring to the drawings: l

` Fig. 1 shows in schematic view the controlling apparatus for positioning the typewheel for printing operations in an embodiment of our invention;

Fig. 2 shows, mostly in section, a slipping clutch through which motion is communicated to apparatus of the embodiment of our invention herein illustrated and described;

Fig. 3 shows in isometric view the transmitter operating mechanism;

Fig. 4 is a view partly in section showing the arrangement of portions of the apparatus of the transmitting mechanismpf Fig. 3;

Fig. 5 is a schematic view of printing mechanism adaptable for use in the said embodiment of our invention;

Fig; 5A is a view of some of the apparatus of Fig. 5 in said elevation;

Fig. 6 is a schematic view of paper carriage controlling mechanism adapted to be employed in the said embodiment;

Fig. 6Al is a side elevational view of a paper carriage and associated mechanism adapted to be employed in the said embodiment;

Fig. 'I is a view of controlling mechanism comprising a motor circuit switching means adaptable for use in apparatus ofthe said embodiment; l l

Fig. 7A is an end view of some of the apparatus illustrated in Fig. 7

Fig.- 8 is a circuit diagram of some of the electrical circuits which may be employed in the said embodiment of our invention:

Fig, 8A is a view of the circuit arrangement of Fig. 8 but with certain of the apparatus thereof indicated in a different operative position;

Fig. 9 is a diagrammatic view of an electrical circuit adapted to be employed in the said embodiment of our invention;

Fig. 10 is a diagram chart relating to character type selection; and

Figs. 11 and 12 are views of a contact finger and ratchet wheel, respectively, illustrated in Fig. 3.

In the above different figures of drawings, the same parts are designated by like reference characters.

Before discussing the drawings, however, it is well to note, generally, that in the illustrated system embodying our invention-operation of the receiving station is controlled through the use of an impulse system of short and long impulses, which makes it possible to transmit and select a comparatively large number of characters with few impulses and with a reasonably simple machine. In the main the transmission of the character impulses is accomplished with a standard typewriter keyboard and a series of motor driven cams, operating upon a. common contact, and, the selection is made possible through a three way operation of a pair of escapement fingers on three escape wheels, combined with a type wheel having three rows of type characters around its periphery. The short impulses advance the type wheel one division at a time and the longer impulses advance the wheel one or more divisions for each impulse and shift the wheel to one of the three rows of characters. Apparatus is also provided for the spacing and return of the paper carrage, the starting and stopping of the machine (both manual and automatic) ink ribbon feed and control, printing, signaling and for the power supply (mechanical and electrical).

The description of the system, the details of construction of the apparatus and mode of operation thereof is hereafter given, for convenience, under the following headings:-

Selector mechanism, illustrated in Figures 1 and 2.

Transmitter mechanism, illustrated in Figures 3 and 4, 11 and 12.

Paper feed and carriage return, illustrated in Figures 6 and 6A.

Ink ribbon feed and printing mechanism, illustrated in Figures 5 and 5A. l

Motor and line switch, illustrated in Figures 'I and 7A.

Line circuit and operation, illustrated in Figures 8 and 8A.

` Machine circuit and operation, illustrated in Figure 9.

Escape wheel and typewheel chart, illustrated in Figure 10. Selector mechanism The typewheel 1 I, upon which the printing type characters appear, has, in the embodiment illustrated, three rows of type around its periphery, the three rows being herein arbitrarily called channels I, 2 and 3 (left to right) and, each row of three characters across the face of the wheel is herein arbitrarily called a division. The Wheel is loosely mounted, but is keyed to the rotatable driven shaft 12 in such a manner that the wheel will rotate with the shaft at all times, but it can also be shifted longitudinally of the shaft at any time. The wheel has, in addition to the hole in. its hub for the shaft 12, two separate holes near its rim through which two pins protrude, and

' ture 85 of magnet 81.

which pins are carried by a yoke 13, which is rigidly secured to the shaft 12. As the shaft 12 is rotated the yoke and pins 14 will cause the typewheel to be rotated also, and at the same time, the Wheel may be axially shifted longitudinally on the 5 shaft and pins. This arrangement makes it possible to bring any one of the several printing type characters on the typewheel 1l to a position in alignment with the path of the printing hammer, later to be described. The selection of the indi- 10 vidual characters in any one channel is accomplished by the operation of an escapement unit which will now be described.

Three escape wheels 15, 16, and 11 are preferably closely positioned together and associated as 15 one unit in'practice, but, in the drawings, these are shown separately, in order to better explain and illustrate the essentials and mode of operation of the unit. Escape wheel 15, has a definite number of teeth, the amount depending upon the 20 largest number of divisions provided in any of the channels; one tooth is provided for each of the divisions thereof. Additional teeth may be provided for various operative purposes. Escape wheel 16 is preferably of the same general design, 25 except that it has fewer suitably spaced teeth. Escape wheel 11 is also preferably of the same type with the exception that it has but one tooth. The number and disposition of the teeth on the different wheels that make up the escapement 30 unit are varied for reasons which will be apparent from the following description.

This set of escape wheels is rigidly mounted on shaft 12 and rotate therewith. Operating in conjunction with, and, controlling the movement of 35 the escapelwheels is a set of two finger units, comprising pawls, 18 and 19, each finger unit being composed of a finger and a grooved sleeve |86 capable of sliding on a shaft 80. The shaft is pivoted at each end so as to oscillate to the limit 40 of the finger movement on the escape wheels. Fixed to the center of shaft 80 is a hub 8|, to which is connected a link through which the oscillations are transmitted to the shaft. The hub also carries a pin 88 which passes loosely through 45 a hole in each of the two fingers and which communicates the oscillatory movements from the hub 8l to the fingers and at the same time permitting the fingers to move freely longitudinally of the shaft. The oscillatory, or rotary motion of 60 the shaft 80 and fingers 18 and 19, is communicated through the link extending from the arma- The armature is pivoted on a pin spaced therefrom toward the observer and spring 9| spaced from the pin toward the 55 observer normally retracts it from magnet 81 and also keeps finger 18 in engagement with escape wheel 15 through the link connection. The horizontal motion of the fingers 18 and 19 is controlled by the magnets 89 and 88 through 60 armatures 83 and 84. In their normal position the fingers 18 and 19 are in alignment with escape wheel 15, the finger 18 engaging same at the top. Should magnet 88 be' energized, its armature 84 being engaged in the slot in the hub of finger 19 65 will cause the finger to -move to the left along shaft 88 and align it with escape Wheel 18. This same operation also takes place with magnet 89, armature 83 and finger 18, this finger aligning with escape wheel 11 when moved along the shaft 80 70 to the right.

When magnet 81 is energized, armature 85 through its link connection to shaft 80 will cause finger 18 to move upward and free of the tooth of escape wheel 15 and bring nger 19 upward into 76 engagement with another tooth of the escape wheel 15.

The shaft 12 carries at its right hand end, one clutch element of a friction clutch 82, the second clutch element associated with the element 82 (see Fig. 2 to be described), being driven by an electric motor while the machine is operating. The shaft 12 is adapted to be driven through the friction clutch 82 by a motor driven shaft 92. During such periods wherein current is not applied to the magnet 91, the finger 18 holds the shaft 12 stationary, by engaging a tooth on escape wheel 15 and by virtue of the slipping occurring between the two elements of the friction clutch Owing to the frictional drag of the clutch unit, there is applied to the shaft 12 a steady torque which causes rotation of this shaft at all such times when it is released by the escapement unit.

If now, energy is applied to magnet 81, fingers 18 and 19 will be raised, allowing the escapement is applied to the magnet 81 the typewheel will be advanced to some predetermined division, depending upon the number of impulses in the series.

As can be understood at this time, if all the escape wheels were divided into a great many divisions, it would require a long series of impulses to rotate the typewheel to the desired characters. This would require a comparably longer time for transmission so in order materially to reduce the number of impulses required for a definite number of characters and, consel quently, to considerably reduce the time required for telegraphic transmission thereof, the escape wheel 16 is brought into operation through the shifting of finger 19, resulting from a movement of the armature 84, into alignment with escape wheel 16. Armatures 85 and 83 so differ from armature 84 in weight and other factors affecting their inertia and the forces effective upon them are so proportional that they differ in their rates of responsiveness to the operative magnetic forces exerted upon these characteristics to cause armatures 85 and 83 to respond very quickly whereby they will be actuated by both short and long impulses of current passed through their electro-magnets and armature 84 is relatively sluggish and responds only to longer continued impulses of current. From the foregoing, it is obvious that, if current is applied to magnets 81 and 88, at the same time, if only for a sufficiently short period of time, only armature 85 will operate and the typewheel will be stepped around accordingly, as before described; however, should a longer impulse be simultaneously applied to both magnets, both armatures 85 and 84 will be operated.

As before stated, upon each operation of the armature 85, the typewheel 1| will be rotatively advanced one division, and if the impulse should be a long one whereby armature 84 is also operated, nger 19 will be shifted over in alignment with escape wheel 16; if now the finger 19 comes into engagement with such a. tooth on wheel 16, as may be disposed one division further around the wheel than the normal position of the nger,

the typewheel will then be advanced but one division; however, should finger 19 be brought into relation with escape wheel 16 at a point where the approaching teeth in its rotation have been receded, the result of the longer impulse r 5 will be to' allow the typewheel to travel a greater distance, or, several divisions depending upon the number of teeth omitted on the wheel in the distance moved. The typewheel can,` therefore, be advanced to selected position muchfaster with fewer impulses than would be otherwise possible. It has been above stated that if finger 19 comes into alignment with a tooth on escape wheel 16 which follows the tooth in normal relation with the finger 19, the ytypewheel will be advanced but one division. Now, thi-s condition holds good forthe first two divisions that the typewheel is advanced by any series of impulses the typewheel is never advanced more than one division for each of the first two impulses, 2o whether they be long or short, due to the fact that there are two teeth provided on Wheel 16 that engage with the finger 19 on the ilrst two divisions, if the impulses received while the finger is aligned with wheel 16 are of the longer con- 25 tinued character.

This makes it possible to utilize the movement of armature 84 on the rst two impulses for the shifting of the type wheel from its normal position in channel l, to either of the channels 2 or 3. 80

The shift and control of the typewheel is accomplished as followsz-Typewheel 1I is held in its normal position by arm 93 secured to the armature 94 of magnet |84 engaging within a slot in the typewheel hub and, as shown, is 95 pivoted at its 'lower end. Any movement of arm 93 to the left, will cause typewheel 1I to be moved along the shaft 12 in the same direction and, for the same distance. The movement of wheel 1l through arm 93 is controlled by an escapement 40 arm 95 and a pin 96. The arm 95 is pivoted at its extreme right end 48 which, also carries a right angle slotted extension 49. It can be seen, that, if an impulse is imparted to the slotted extension, in line with the slot 41 and, in a left 45 hand direction, the first tooth 46 in the escape- 'ment which engages pin 96 willbe lifted clear of the pin, and the arm 93 will move to the left until pin 96 engages the single tooth 45 on the lower side of the arm. Following the impulse, 50 the arm will drop back to its normal position,

' allowing the pin to shift from the lower to the second of the upper teeth 44 of the escapement. This permits an axial movement of the typewheel moved by the spring 91 an amount equal 55 to the width of one channel and aligns the second channel with the printing hammer not herein shown but adapted to be reciprocated in a plane at right angles to the axis of the shaft 12 to compress interposed layers of typewriter printing ribbon and a sheet of paper upon which the typewritten record is to be made against the type raised characters on the typewheel 1I as hereinafter more specifically described. A second impulse to the arm 95 will cause the wheel to be 95 l shifted to the third channel in the same manner as to the second, the impulses mentioned, being communicated to the arm 96 by movement of armature 94, which in turn operates responsively to long impulses of current through electromagnet 88.

By virtue ofthe axial positioning of the typewheel, controlled by the first two impulses in magnet 88 and due to the fact that its armature 84 only operates responsive to the longer im- 76 pulses, the typewheel may be shifted to any desired channel by the transmission of the rst two impulses of any series in a combination of long and short impulses. For example, although two short impulses will not effect the armature 84 to shift the wheel, one short and one long impulse will shift it to the second channel; two long impulses will shift the wheel to the third channel since the long impulses are effective to operate armature 84, which controls the actuation of escapement 95.

Contact between attracted armature 84 and cscapement arm would cause the typewheel to shift from the first to the second or third channel; so it is desirable that this should not happen on any but the rst two impulses in any one series since, otherwise, the desired selection would not b'e accomplished. To prevent such undesired operation, control over the escapement 95 is exercised by a cam S8 on the shaft 12 adapted to actuate a bale plate element, comprising a sleeve |00 to one end of which is fixed an arm 0| operated by cam 98, and to the other end a flexible thin metallic guard or baffle plate |02 is secured. This unit is free to turn on the shaft |03. When the arm |0| is, once during each rotation of the shaft 12, raised by the cam 98, the flexible guard or bafile plate is disposed directly between the projection 99 on armature 04 and a bifurcated end of the arm 95. The cam holds the baffle plate in this position while wheel shaft 12 rotates two divisions from normal. Just before the third division is reached in the rotation of the shaft 12 the cam 90 releases the arm |0| and the baffle plate swingsclear of, and out of alignment with the bifurcated arm of escapement 95 and armature 84. In this position the armature has no effect upon the escapement 95 due to the projection 99 on the armature passing freely between the forks of the end of the escapement lever arm and the typewheel will remain in the position previously achieved through the influence of the first or second impulses of a particular series.

'I'he typewheel is restorable to its normal position by the attraction of magnet |04 on the armature end of the arm 93. The armature 84 operates the typewheel shifting mechanism and armature 83 operates the paper carriage shift by actuating the paper carriage escapemont pawl 4|; a projection armature 03 is adapted to activate the escapement pawl 4| directly and at any time the armature 83 is moved. The carriage escapement is described elsewhere herein and may vary in construction, the usual typewriter spring-propelled carriage b`eing s uita-ble for the purpose.

The armature 83 engages thegroove in the sleeve |06 of finger 1B and when magnet 89 is energized, its armature 83 will shift the finger 18 to the right and in alignment with escape wheel 11 which has but one tooth.

This operation permits the shaft 12 with all its associated units to return to normal position, after the second division in the revolution is reached. The single tooth 11A is'inalignment with the normal position of the finger 18 on the escapewheel 15 and after one or more divisions have been traversed by the units on the shaft 124 and the finger 1S shifted to escape wheel 11, the shaft and associated units will continue to rotate for the remainder of one revolution after which the nger engages the single tooth 11A at which time the mechanism will again be in normal position. This restoring takes place after the selection and printing of each character, as the shaft 12 and typewheel 1| complete one revolution of each cycle of operation.

Cams |01, |08, and |09 operate contact combinations ||0 and and H2 at times prede- 5 termined by the radial disposition of the cams on the shaft, during each revolution of the shaft 12. Cam |09 operates contacts ||2 indirectly through the movement of armature ||3. When shaft 12 is in its normal 'position cam |09 is in l0 engagement with armature ||3 and holds same in an operated position in relation to the magnet Illi and keeps contacts ||2 open. The relation and functioning of this combination will be explained later. 15

Springs such as 9|, 91, `|'|5, H6, ||1, and H8, are provided for the return operation of the armatures and all moving parts. ||9 represents bearings for shaft 12. It will be understood that suitable adjustable stops of well known types, butA 20 not shown herein may also be provided to limit the movement of the several oscillating members.

The friction clutch 82 is a part of the selector unit and the clutch element thereof attached to the shaft 12 is shown (Fig. 2) as a hollow cham- 25 ber or drum supported from one end by a sleeve encircling shaft 12. The clutch element thereof fastened to the drive shaft is shown as a block through which is cut a hole at a right angle to the shaft. Riding free within each end of this 30 hole, is a thin sleeve into which is placed a friction pad of preferably fibrous material, such as felt which acts to frictionally engage the drum to rotate same when vthe clutch unit is assembled and operated. This block rotates within the drum 35 and two springs pressing against the under side of the sleeves force the friction pads against the inner surface of the drum. With a tapered sleeve as shown on shaft 12 the springs can be adjusted to the right tension and a very smooth 40 and positive operation of the clutch obtained.

The secured typewheel shift member 93 also operates the contact group' 440, the right hand contacts being closed when the wheel is set irl the first channel, and, the left contacts are closed 45 when the wheel is in the second or third channel.

Transmitter mechanism Referring now to Figs. 3 and 4, wherein a unit of the transmitter is schematically shown, the 50 transmitter comprises preferably a bank of units each unit being substantially the same with the exception of the indentations in the periphery of cams thereof. As all units are alike in their construction, only one will be described, it being understood that a group of these units are assembled on a common shaft and disposed parallel with each other. The combination composing a complete unit comprises a key lever |20, a connecting rod |2|, a set of escapement fingers |22 and |23, 60 a ratchet wheel 24, a pawl |25, a slotted disk |26,

a cam |21, a drive shaft |28, a contact finger |29, a finger shaft |30, a contact arm |3| and a set of contact springs |32. The shaft |28 is driven in any suitable way, such as by an electric motor, 65 and keyed to the shaft is a ratchet wheel |24, which revolves with the shaft at all times. Closely associated with the ratchet wheel on shaft |28 is a cam |21 slotted disk |26 and a pawl |25 which as shown in Fig. 4 is combined as one unit 70 on a sleeve. This unit is loosely carried on the drive shaft and is held stationary by the escape ngers when the unit is not being operated; The pawl is loosely mounted on the surface of the slotted disk adjoining the ratchet wheel and in 75 aoamvs 5 such a manner that the hooked end can be engaged with the teeth of the ratchet wheel and whereby the inside edge of the small right angle tail projection |34 on the pivot end of the pawl is parallel to, and, adjoining the slot |33 in the disk |26. An angularly disposed end |35 of the escape finger |22 is shaped so as to enter the slot in the disk and hold the pawl clear of the ratchet wheel, and at the same time keep the cam and l0 the disk from rotating. Should the nger |22 be withdrawn from the slot in the disk, the pawl will be brought into engagement with the ratchet Wheel by the pawl spring |36 and the cam unit will be carried around with the rotating shaft |28. If now, the finger is released before one revolution of the disk takes place. the end of the nger will come into contact with, and ride on, the edge of the disk until such a time as it reaches the slot in the disk and the pawl thereon. i Just before the end of the finger again enters the slot it will engage the angle portion |34 of the pawl, which at this time covers the slot due to its being in engagement with the ratchet wheel and, therefore, tipped at a greater angle, and will carry the same back and parallel with the slot. The pawl is thus disengaged from the ratchet wheel and .the nger permitted to resenter the slot, thereby lockingthedisk and cam against further rotation. This operation only obtains when the nger |22 isreleased before one revolution of the shaft |28 is completed, since if the ilnger |22 is held away from the disk for a greater period of time, the cam unit would make more than one revolution which is not desirable. The escapement action of the two ngers |22 and |23 and the pawl |25, provides for automatically insuring correct operation in this respect. The finger |22 is pivoted at |31 at its end, opposite the disk; the nger |23 is pivoted on the finger |22 at |38 about midway of its length. The right hand end of the finger |23, adjoining the disk, 'is angularlv so disposed and shaped as is the end of nger |22 so as to permit it to enter the slot in the disk and engage the end of the pawl, under certain conditions when obtained. The opposite end of the finger is bifurcated, one fork thereof, |39. `being curved upwardly and at its end is'secured an end of a helical restoring spring |40. attached at its other end to a support |4| and disposed to exert an upward eiort substantially ina direction at right angles to the main portion of the finger 22. The other fork |42 extends toward the pivot |31. The adjustable link |2| connects the end of the fork |42 to the key lever |20. the connection to occurring at a point midway thereof. If now, the key lever' |20 be depressed, the link |2| will exert a downward pull on the extension |42 of finger |23 and on the restoring spring |40 rocking the nger |23 counter-clockwise as viewed in Fig. 3. The opposite end of the finger |23 is thereby raised up against the disk by the rocking of finger |23 on its pivot |38 on iinger 22.

During this movement of the finger |23. neer m |22 will remain in its normal position. du. to the. relative positioning of the parts. the upward pull of the spring being exerted on a three point' suspension-namely, the pivot rod |31 at one end, the disk at the opposite end and the pivot m of nger |23 at its center. If, after the end of the nger |23 comes into contact with the disk. the link |2| is moved farther downward by depression of the key lever |20, the pivot point of nger |23 will be moved downward also, the end y; of the finger in contact with the disk acting as a pivot. As the finger |23 is pivoted on nger |22, this operation will cause nger |22 to be drawn down and rotated on its pivotrod |31 in the left-l hand end. This movement of finger |22 will effect the withdrawal of its end |35 out of the slot 5 in the disk and free Vthe disk |26. At the moment the finger is withdrawn from the slot |33, the pawl will be spring pressed into engagement with the ratchet wheel, and thus the cam unit will be rotated by the drive shaft. When one revolution 10 thereof is nearly completed and the finger |23 is held against the disk by the pressure on the key lever, the end |43 of the linger |23 will enter the slot |33 and effect the disengagement of the pawl from the ratchet wheel, thus locking the ca'm 15 unit as mentioned before. Now, the pressure on the key |20 being removed and the key returned to its normal position, the spring |40 will raise linger |22 into contact with the disk, after which with a continued upward movement the key fin- 20 ger |23 will be withdrawn from the slot |33 and through the operation of the pawl and ratchet wheel the cam unit will be advanced until finger |22 enters the slot |33 and again releases the pawl and locks the cam unit. 25 The arrangement of the escapement as a whole is such that the cam unit will make butl one revolution for each complete operation of the key lever, regardless of the length of time that the key lever is held in a downward position. The 30 action of the two ngers on the disk and pawl is to always bring the idle finger into operative position before the withdrawal of the locking finger from the slot in .the cam unit, the idle finger causing the release of the locking finger 85 by the movement of the f-ulcrum points along the length of the fingers. The key lever used may be of the type common to all typewriters and requires no explanation. The cam section of the unit just referred to has a toothed edge, the 40 teeth being so disposed thereon as to operate the contact |32 according to the impulse code to be transmitted by that particular cam. In contact with and operated by the toothed cam is one end of a contact finger |29, this end of which holds a rollerv |44 for the reduction of friction between the finger and the cam. As shown in Fig. 11, the iinger is constructed with a hole through the opposite end through which passes a finger shaft |30. An adjusting screw |45 is preferably prov50 vided in the end projecting beyond the shaft |30. The nger has a slot |46 throughout its length receiving the roller |44 at its one end and a pin |41 rests within the slot at the other end of the finger. The finger is loosely mounted upon the shaft |30 and directly in line with the slot, a hole being cut through the shaft at right angles thereto, into `which is secured the pin |41. The

- slot 461s of 'such dimension that the pin does not come into contact with the body of the nger, in 80 its movement on the shaft, but the pin does engage the end of the adjusting screw |45 provided inthat end of the finger.

It can be seen that an upward movement of the finger by the cam will cause the shaft |30 65 to be rotated, and also thatthe shaft could be rotated in a clockwise direction, as seen from the right, without imparting any movement to the finger. Each time that the cam is rotated the irregular surface of the cam will cause the nger to be intermittently raised to impart movement to the shaft through the screw and pin, but in the case where two or more like cam units are mount-v ed upon the same shaft, the operation of one cam and nger unit will not affect the others, as the shaft |30 can be rotated in a clockwise direction by any one unit and through the functioning of the screws and pins, the others will remain stationary.

Thus. a series of impulses are communicated to the contacts |32 through any contact finger |29 from one of a number of cam units without interference. The contact arm |3| secured on shaft |30 causes the contacts |32 to be operated responsive to movements of any selected nger riding on the irregular surface of a cam. This construction makes it possible to use but one set of electrical contacts for an indefinite number of cams, resulting in a comparatively simple but positive impulse transmitter. Shaft |28 which is the power driven shaft, is preferably equipped with bearings, not shown, as is also the shaft |30, as indicated at |54.l In operating the transmitter, the depression of `any key will cause the cam associated with that key to make one revolution.v Each cam, having a different series of teeth on its edge, will cause its associated contact finger to oscillate the finger shaft, which in turn will close and open the set of contacts |32 in unison therewith. In this way the desired series of impulses, corresponding to any character, can be transmitted over a wire. A further explanation of its relation to the line and selector will be found elsewhere in the description.

Paper feed and carriage return In the typewriting portion of our improved mechanism, the carriage return and the paper line feed is cooperatively effected. This part of the description will cover th'e paper carriage mechanism shown in Figs. 6 and 6A, which indate a roll of paper |52, the feed rollers |56 and' |51 and the paper line spacing mechanism, the preferred relation of the equipment being indicated in Fig. 6A.

Four grooved rollers |55 are disposed one at each of the four corners of the carriage frame having the end frame members |5|, to permit the frame to travel on a pair of preferably circular rails fixed to the machine bed 43. The roll of paper |52 is placed upon a movable shaft |58 which is suspended on and between the end frame members |5| of the carriage, the ends of the shaft being so reduced in diameter as to enter and rotate freely in a slot |59 in each end member. After the paper is placed in the carriage, the free end of the paper is directed between the two feed rollers |56 and |51, which feed and control the movement of the paper through a set of vertical guides |60 that direct theepaper upwards and over the top of themachine to cause it to pass between the typewheel 1| at the rear of the carriage and the inking ribbon IGI and printing hammer 291 at the front.

'I'he paper roll being mounted upon and moving with the carriage continuously is in alignment with the feed rolls and guides and, therefore, the paper will not have its edges entangled in the guides and mutilated, rendering the machine inoperative. The lower ends of the paper guides |60, as well as the inner guide |15 are so shaped its channel. As can be noted, although the paper might be fed into the feed rolls from the bottom, rather than from the side of the roll, this half turn of the paper around the upper feed roll takes a part of the curl from the paper and leaves just enough as to cause the paper to follow over the back of the machine after it passes out of the guides at the top of the carriage.

It is evident that to reverse the direction of rotation of the paper roll in the carriage would mean that the paper would travel over and in front of the carriage and key board and would not only interfere with the operation of the machine but would cut off all visibility in respect to the printing. As the roll of paper is free to rotate in the carriage the feed rolls |56 and |51 unwind the paperfrom the roll |52 and force it up through the guides |60 and |15 and out of the top of the carriage, passing the typewheel and the printing apparatus.

On one end of the feed roll shaft |56 is a ratchet wheel |62 which is engaged by a pawl |63 pivotally carried on the lever arm |64. The arm |64, pivoted at one end, terminates in a roller |65 at the other, which roller contacts with the cam |66 on the carriage return rack |61. The lower end of the pawl |63 rests on a pin |68 when in its normal position. The angular position of the spring |69 relative to the pawl and arm, causes the pawl and arm to be drawn downward and at the same time brings the pawl into contact with the pin. The movement of the lower end of the pawl over the pin swings the upper end away from, and free of the ratchet wheel which permits rotating of the paper feed rolls in either direction during the threading of the paper.

If now the roller end of the arm |64 be raised, the pawl will be carried away from the pin and the upper end of the pawl will engage a tooth in the ratchet wheel. A further movement of the arm will rotate the ratchet wheel and feed the roller until the arm movement is arrested,

wheel will determine the movement of the paper since each movement of the arm turns the ratchet and roll the distance of one tooth space. To insure an arcuate line shift spacing of the paper an indent roller |1| and leaf. spring 290 is associated with the ratchet wheel and is adapted to center the ratchet wheel.

Mounted upon the back of the paper carriage is the toothed return rack |61 for the return of the carriage to its right hand position on the machine, effective to shift the paper each time that the carriage is returned. The rack is slotted at |12, Fig. 6, near each end and is suspended on the carriage by two screws |13 passing through the slots and into the frame end members |5| of the carriage. suspension, the rack can be moved a definite distance lengthwise along the carriage, being restorable `to normal position by the spring |14. Mounted upon the rack |61 and in line with the paper shift arm |64 is a cam |66.

Through the screw and slot Each time that the rack is moved along the carriage on the screws |13 the cam will raise the shift arm by virtue of the roller carried on its end, riding up the incline on the top edge of the cam. This causes shifting of the paper in the carriage, an amount equal to one typewritten line for each movement of the rack.

When the end of the slots in the rack engage the screws |13 a further movement of the rack will pull the carriage along its track to the end of its travel across the machine. Should the carriage be in its extreme starting position on the right hand end of the machine and the rack be moved on its supporting screws the paper will be shifted up but no movement of the carriage will take place. The mechanism for moving the rack |61 to shift the paper or to shift the paper and return the carriage will now be described.

Engaged with the rack is a gear |16 combined as a unit with a helical gear |11 which rotates on a stud |18. The helical gear is meshed with a similar gear |19 on the drive shaft |80. 'Ihis gear carries tw`o pins |8| projecting from one side thereof with which two like pins |82 in a sliding sleeve |83 is adapted to engage. The sleeve |83 is loosely carried on the drive shaft |80, but is keyed to the shaft and rotatable thereby. Ihe key pin |84 in the hub of the sleeve extends into a slot |85 in the shaft. If the sleeve is moved along the shaft until the pins carried on the sleeve |83 engage those carried by the gear |19 the shaft will cause the gear combination |16 |11 to rotate, which in turn will move the rack |61.

Engaging within a slot inthe sleeve |83 is one arm of a bell crank |86 which is pivoted at the junction of two arms. It engages a. pin |81 on a lever arm 88 at the end of the second arm. The lever arm |88 is pivoted at 209 at one end and extends to a point in line with the movable rack |61 on the carriage, this extension carrying an adjusting screw |88 which contacts with the end of the rack. 'I'he lever |88 is also tied to the bell crank |86 by a spring |90. About the center of theA upper arm" of the bell crank |86 is a pin |8| which engages a hook on the pawl |92 pivoted on the top of the armature |93. The pawl |92 has a small extension beyond its pivot point which contacts with a stop |88 a spring |95 holding the pawl in engagement with the pin |8| in the bell crank |86 also holds the armature |83 in its inoperated position. Cooperating with the armature |93 is a magnet |96 and upon energization thereof the mechanism will operate to return the carriage as will presently appear. f

When the armature |98 is attracted by the magnet |96 it will, through the pawl |92, move the bell crank |86 on its pivot, to cause the sleeve |83 to be moved along the shaft |80 to eect interlocking the pins |8| of gear |19 with the pins |82 of the sleeve. At the same time the lower arm of the bell crank lever |86 is raised above the pin |81 in the lever arm 88 and this arm will then be drawn against a pawl |91 by the spring |90. As the lever arm |88 moves over toward the pawl |91 the pin |81 will be projected under the lower arm of the bell crank |86, lock' ing it against return to normal position and locking the clutch pins into clutching engagement. The drive shaft |80 through the clutch and gears now causes the rack |61 to move the carriage, if the carriage is not in its extreme right hand position, until the end of the rack |61 contacts with the contact screw |88 of the lever arm |88.

Continued motion of the rack will move the lever arm |88 back to its normal position, thereby increasing tension of the spring |90 and freeing the lower end of the bell crank lever |86 from the locking action of the pin |81, releasing the bell crank which will be returned to normal position, and disengaging the clutch and locking the lever arm |88 in normal position.

Near the extreme end' of the stroke of the armature |93 above referred to, the extension of 1o pawl |92 makes contact with the stop member |94 giving the hooked end of the pawl |92 a downward motion to discngage the hooked end of pawl |92 from the pin4 |9| in the bell crank, freeing the same to permit`l't to return to normal 15 under the control of lever arm |88.

By virtue of this disengagement of the pawl, current through the magnet |96 may be prolonged indefinitely without interfering 'with the disengaging of the clutch.

Provision is also made for the engagement of the clutch elements |8|-|82 when the carriage has reached itslimit of movement across the machine toward the left and it is required that the carriage be returned to the opposite end by the motor, not shown, driving shaft |80. This is ac- Y complished by actuation of the lever arm |98 andv the connecting rod |98. When the carriage travels to the left end of the machine within the xed. rack 200 comes into contact with the upper end of the lever arm |98, moving it against the power of the spring 20|. Connected to the arm |98 and bell crank |86 is the connecting rod |99, one end of which is Yhooked into a hole 220 in the arm |98 and the other end of which is passed around 35 the upper arm of the bell crank lever |86 and has its extreme end then bent at a right angle, to engage the bell crank to move the same whenever pulled by the arm |98. As the carriage moves along, the rack 200 will move the arm |98 40 and the rod |99 until the hooked end 42 of the rod |99 operates the clutch mechanism in the same manner as before described for operation by the movement of armature |93.

By operating a set of contacts 202 by movement of the lever arm |98, the carriage may also be returned by the energization of the magnet |96 by current flowing through normally open contacts of the set 202. By energizing the magnet |96 the carriage can be brought to its start- 50 ingposltion at any time, or it will be always automatically returned to this position upon reaching the extreme opposite position on the machine; also the paper will be shifted upward each time that the carriage is moved to return lt or as many times as is desired after the carriage has reached its limit of return travel by energizing the magnet |96 a corresponding number of times.

To prevent the paper vcarriage from spacing when the carriage and paper are being shifted, the small bell crank lever |91 above mentioned is positioned between the fixed rack 200 on the carriage and the lever arm |88. At such times when the lever arm |88 is in an operated position, 65 during the time the clutch is engaged. the lever arm will contact with the projection on the bell crank lever |91 and by rotating on its pivot, the bell crank lever will engage with teeth on the fixed rack 200-with its] hooked end and prevent it and the carriage from moving in a spacing direction, but as the hooked end of the bell crank lever 91 has a beveled end face it will not arrest movements of the carriage in the other direction.

Whllethe carriage is being returned to the start position, the beveled end of the bell crank lever will cause it to ride over the teeth on the rack, the spring |90 acting as a tension member through the lever arm |88. The shaft |80 is driven by a motor through suitable gearing.

'I'he following description applies to the driving of the carriage in the spacing direction. Attached to the fixed rack 200 on the paper carriage is one end of a tape 203, the other end of which is wound around a tape drum 204, carrying a gear 2 05. Both gear and drum rotate on the stud 206. l

Meshed with the gear 205 is a sector gear 201, pivoted at its lower end and operated by the spring 208. By virtue of the pull exerted by the spring 208 the sector gear 201 will exert a rotational effort upon the gear 205 and the drum 204, winding the tape on the drum and pulling the carriage across the machine when released by an escapement mechanism comprising a double acting pawl 4|, and escape wheel 23|. The angular position of spring 208 in relation to the sector gear 201 is preferably such that when the sector gear is at that one extreme position wherein the spring 208 exerts the least effort upon it, a line through the pin 2 I9 and the center of the sector pivot stud will be disposed substantially at right angles to the spring 208.

Such an arrangement results in the spring 298 exerting an effort through greatest leverage, upon the sector gear at the time that the spring is extended the least, and this results in a more even torque being applied to the drum 204 by the spring at all points in its rotation, causing the tractive effort exerted upon the carriage by the spring to be nearly equal throughout its travel.

Supported upon the fixed frame of the machine, is the escapement unit comprising a gear wheel 230 meshed with the rack`200 and having a ratchet wheel 23| rigidly secured to one face thereof. This gear and ratchet wheel rotate on a stud 2| xed to the machine frame.

Co-operating with the ratchet-23| is the double acting pawl 4| which permits the ratchet wheel to advance one tooth for each oscillation. This pawl is operated in one direction by a spring 233 and in the other by the armature extension 83 as shown in Fig. 1.\ Upon armature 83 being operated by its magnet 89, the escape or ratchet wheel 23| will be advanced one tooth as will the gear 230, the rack 200 and the paper carriage, the stepping of these parts being imparted by the spring 208. When the carriage is being returned by power of the motor as before described, to the starting position, the pawl and the ratchet wheel will, through their angle of contact, act in a well-known manner as a free escapement and exert but little retardation on the carriage. l

Fig. 6A shows the relation of the paper carriage parts to the typewheel 1|, printing hammer 291 and carriage supporting tracks. In the system described the paper can be spaced upward, the carriage can be returned to the starting position,

and the carriage moved in a step-by-step man-- .ner across the machine as the printing goes on,

every operation being accomplished automatically or manually as desired.

It will be understood that suitable bearings and supports are provided for all parts throughout the machine, these being well understood and omitted herein for simplicity of illustration of the operative parts. The V-shaped rollers and round tracks upon which thepaper carriage travels, comprise a self cleaning and self-aligning Ink ribbon ,feed and printing mechanism A standard typewriter ribbon |6| is preferably used for the ink supply for printing purposes and we preferably employ improved mechanism to control the movements of the ribbon during the printing process. This mechanism is so arranged that the ribbon is moved in a fully automatic manner whereby the machine may be operated to receive telegraphic messages when unattended.

With this in view we provide a pair of ribbon roll carrying spools 24| and 242 which are mounted upon and loosely keyed to the upper ends of vertical shafts 243 and 244, respectively. These shafts are driven by gear pinions 245 and 246, respecvely, thro-ugh universal joint connections 241 and 248, respectively; which are so made as to comprise laterally extending arms 249 carried by the ends'of the shafts 243 and 244 projecting within an upper bifurcated clutch element swiveled at 249 upon the upper ends of shafts 250 and 25|, and upon which latter shafts the pinions 245 and 246 are rigidly secured.

While both of the shafts are free to rotate, the ribbon can be withdrawn from either spool and rewound on th-e other spool by rotation of the shaft carrying the latter. The shafts 250 and 25| are each journaled at 252 and 253, respectively, in the shiftable plate 254. The sliding plate is adapted to be m'oved longitudinally upon the retaining pins 255 which have enlarged heads with reduced Shanks passing through longitudinally extending slots 256 disposed at each end of the sliding plate. The universal joint connections 241 and 248, permit lateral displacement of the shafts 25| and 250 relative to the shafts 243 and 244, whenever the sliding plate 254 is shifted longitudinally to displace laterally the shafts 250 and 25 l, and the gears are carried with the shafts at such time.

In alignment with the spur gears 245 and 246 carried on the lower ends of shafts 250 and 25|, are a pair of spur gears 251 and 258 which are so disposed that when the gear 246 is in mesh with the gear 258, the opposite set of meshable gears 245 and 251 will be demeshed. Contrawise when the gears 245 and 241 are in mesh the gears 258 and 246 will be demeshed.

The gears 251 and 258 are meshed With and driven by a train of other gears from a common driving pinion 259. The intermediate gear for the gear 251 being shown at 260, and for the gear 258 there is provided an interconnecting gearing comprising a pinion 26| having an enlarged gear portion 262, afiixed thereto and a pinion 263 intermediate the gear portion 262 and the pinion 25S. Non-rotatably secured on the gear pinion 259 is a ratchet wheel 264. Journaled on the shaft carrying the pinion 259 and the ratchet wheel 264 we provide a gear 265 in mesh with a rack !2 rigidly mounted upon the front of the paper carriage and longitudinally reciprocable therewith a pawl 266 is pivoted at 261 upon the upper face of the gear 265 as is also a leaf spring 268 which engages with the pawl 266 to resiliently press it toward meshing position with the ratchet wheel 264. This arrangement permits relative rotation of the gear pinion 259, with respect to the gear 265, in but one direction. By virtue of this arrangement the pinion 259 is caused to rotate in one direction,

, the'shafts 250 and 25| driven thereby but when the carriage is returnedto start the printing of a new line there will be .no driving of the pinion 259 and the trains of gears in mesh therewith. To more positively prevent improper rotation of the trains of gears upon a return movement of the carriage, because of possible frlctional eil'ect in the escapement comprising the pawl '266 and ratchet wheel 264, we provide an additional spring press pawl 269 to prevent rotation of one of the gears in one of the trains, here shown as the gear 263.

'Ihe above arrangement is provided for the purpose of preventing rotation of the ribbon spools 24| and 242 during the return movement oi' the carriage and to provide for a step by step rotation of the ribbon spools as commonly required in typewriting apparatus during spacing movements of the carriage, and upon spacing movements that spool whose driving pinion- 245 or 246 is in mesh with the intermediate trains of gears driven by the pinion 259, it will be rotated to wind the ribbon |6| upon it.

Parallel to the shafts 250 and 25| are provided the shafts 212 and 213 which are journaled at each end to the main frame 40. Attached to the lower end of the shafts 212 and 213 in proximity of the fixed bearings 21| are a pair of short lever arms 266 and 28|. Carried by the upper end of each of the shafts 212 and 213 are arms 216 and 211 having rollers journaled in the outer ends. 'I'hese rollers 216 and 219 bear upon the ribbon rolls 24| and 242. The rollers are held in engagement with the ribbon rolls by means of coil springs 214 and 215 substantially about the upper `part of the shafts 212 and 213. The springs are secured at one end 36 and 39 to the main frame and are coiled about the shafts and are secured to the opposite end of the roller arms 216 and 211. The shafts 212 and 213 being parallel to and the arms 216 and 211 being of suitable length, the rollers carried by the arms 216 and 211 will swing toward the center of the ribbon spools, and are caused to follow the ribbon during the winding and unwinding of the ribbon spools on or R by the action of the springs 214 and 215. As shown the ribbon rollers are supplied with the maximum and mini- :f mum diameter of. ribbon rolls thereon. Ribbon roller 24| is at the minimum diameter and ribbon roller 242 is at the maximum diameter. It will 'be seen that any change in the diameter of the ribbon on the rolls will exert varying movements upon the arms 216 and 211 which in turn cause l the shafts 212 and 213 to be rotated, transmitting a pivotal movement to the lever arms 26|! and 28|.

Carried bythe plate 264, and in close relation with the gears 261 and 256, are two pawl members 262'and 263. The pawls are normally held 'in vs positicn against the stop pins 264 and 266 action exerted by the flat I.; 2eand 261'secured to the plate 254. 'I'he pawls are pivoted to the plate 254 the outer ends beingshaped so as to provide a lug on one' side thereof to be engaged by the short arms 266 and 26| opposite sideof the pawlsare provided with a sharp tooth. The `outer end of the pawls terminate in a projection onwhich the springs 286 and 291 exert their force to retain the pawls in inoperative position.

As shown the plate 254 is in its maximum left hand position relative to its lsupport. In this position the tooth on the pawl 282 is disposed in substantial radial alignment with the center of the gear 251, while the pawl 263 in its shifted position is left of the radial center of the gear 256. If the gear 251 is rotated by the carriage, and in the direction of the arrow, and if the pawl 262 is pushed against its spring and into engagement with the gear 251 this gear will draw the pawl along with it until a time is reached when the pawl is released. The pawl being attached to the plate 254 it too will be moved in the direction of the arrow by the active gear until the pawl is released.

Engagement of the pawl with the gear wheel is brought about by the roller arm 216 contacting with the ribbon spools 24|, so that when the diameter of the ribbon on the roll reaches a predetermined minimum the roller ann will transmit -y a rotary motion to the short lever arm 260 so as to abut against the lug 36 on the pawl 262. The rotary motion to the short arm is transmitted by the shaft 212 herebefore described in detail. The same operation is effected by the ribbon roll 242 and roller arm 211 on the pawl 263 when the ribbon has been exhausted to the minimum from the ribbon roll 242.

Heretofore we described the engagement of the pawl and the gear whereby the plate is shifted in the same direction as the gear is rotated. Inasmuch as the plate and pawl move more rapidly than the lever arms 216 and 211 the pawls are carried away from the gears 251 and 256 by the force exerted by the springs 266 and 261 when the 85 short arms are moved away from the pawls, and the pawls are accordingly returned to inoperative position against the stop pins 264 and 265.

To overcome any friction between the pawl and the gear wheel we have provided a means to cause 40 disengagement. Preferably the means provided consists of a pawl 290 pivoted to the main frame of the machine and held in one of two notches 238 and 239 provided on one side of the plate 254, by the force exerted by the spring 289 supported on the main frame of thev machine. It will be seen that shifting the plate 254 in either direction by the gears 251 or 258 lifts the pawl 290 from one notch in the plate and the spring forces the same into the other notch. In this manner the plate 254 is held in position until the ribbon is exhausted from one of the ribbon rolls. It will also be seen that any friction between the pawls and the gears while in engagement with each other, will be overcome by thesnap action of the pawl 296 in entering one of the notches on the plate 254. In this way' the plate' is carried ahead faster than the speed oi' the gear thereby allowing the pawls 262 and 283 to return to inoperative position. v When the plate 254 is shifted to the left the gears 246 and 258 are'l in mesh while gears 245 and 251 are separated, likewise the shifting of the plate 254 to the right will cause gears 245 and 251 to' mesh, while gears 246'and 256 are disen- |35k gaged. From the foregoing it is evident that as e the gear trains herebefore described, are rotated by the carriage rack, and the gears 245 and 246, when either is in engagement with the train gears, the .ribbon rolls will be rotated in one 7o direction or the other, depending upon which of the gears referred to are meshed, thereby causing the' unwinding of the ribbon from the free ribbon roll and winding the ribbon-on the driven roll. It willbe noted that, although one ribbon roll is 7,

termed a free ribbon roll, the roller arms 216 and 211 act as brakes by virtue of the tension exerted on the roller arms by the springs 214 and 215.

The winding and unwinding operation of the ribbon spools takes place in either direction until a time when the ribbon on the free ribbon roll reaches a predetermined diameter, at which times, the reversing mechanism herebefore described automatically shifts the gears 2145 and 246.

A side view of the printing apparatus is best shown in Figs. 5A and 6A and will be hereinafter more fully described.

The ribbon is guided through a pair of guide slots provided in the ribbon elevator 35 and in the upper portion thereof. These guides are supported by a pair of parallel arms 305 at 306 which are pivoted at one end 304 to the main frame of the machine. The ribbon elevator 35 also comprises a curved armature arm 301 fastened together by spacing studs 308. Carried by the elevator 35 and above these studs are two small rolls 294 adapted to rotate on a vertical axis to reduce the friction between the ribbon and the guide slots as the ribbon passes the type wheel.

In normal position the elevator used is in such a position as to leave the top of the ribbon slightly below the point of contact with the paper 33 which receives the printed characters.

stop pin 296 the ribbon will be carried upward in direct alignment with the characters on the typewheel 1 I. Thus a clear vision at all times may be had by the operator, except when the printing operation is taking place. The elevator member 35 is 'forced upward into printing engagement by the action vof the printing hammer arm, 291 armature arm 301, and magnet 300, which will be hereinafter described more in detail.

Disposed below the elevator 35, substantially at right angles thereto is a curved armature arm 301 pivotally supported on a shaft 308 and adaptedA to support on its outer end a magnetic pole piece 299. Upon the end of the armature 301 is pivoted the printing hammer 291. Disposed below and in alignment with the pole piece 299 is an operating magnet 300 supported on the main frame in such a way that the energizing of the same attracts the pole piece` 299 downward rocking the armature 301 causing the printing hammer 291 to be swung upward on its pivot 34 to effect the printing on the paper 33.

The printing hammer is composed of two L-shaped pieces 302 one of which appears in the drawings joined at the ends of their long arms and secured to the hammer head 291 in any Well known manner. The L-shaped members 302 have bearings 303 adapted to support a roller v30| journaled to freely rotate therein. The-long arms of the member 302 normally rest on the shaft 308, adjacent the hammer head 291. A screw 309 is alsoprovided to limit the downward movement of the armature and hammer, and is preferably .adjustable to vary the movement of the armature arm 301.

The action of the above in the elevation of the ribbon and printing hammer is as follows: When w When the elevator member 35 is raised upward against the tal piane.

shorter arms of the point below the proper printing position, and the ribbon would not have been raised.

The above described operation of the combined units is effected by the speedof operation, and the relative positioning of the different co- 5 operative parts. The arms of the hammerunit are set at such an angle from the 'vertical and the hammer is made of such a weight, that a certain resistance to the movement thereof around the pivot 306 results. The angular relationship of the roller 30| to the spacing stud 293 is substantially degrees which tends to cause an upward thrust on the elevator 35.

Cooperating with the previously mentioned factors is the elevator which should be so proportioned in weight as to offer a certain resistance to the raising of the hammer. When its function is completed, the quick movement of the armature 301 by the magnet 300, is resisted by the angle and weight of the hammer and the an- 20 guiar relation of the roller 30| and the stud 293. The force resulting from this reaction is all applied to the stud 293, accordingly the elevator 35 will be raised to a position governed by the stop 296. A t the end of this movement the relation of the 25 roller 30| to the stud 293 is such as to cause the roller to travel under the stud 293 causing the upwardly swinging action of the hammer on its pivot toward the typewheel 1l.

As the hammer is raised and rotated around 30 its pivot `the angle between the roller and the -stud gradually decreases until a point is reached where the movement of the roller is in a horizon- A t this point the roller will ride under the stud while the hammer will continue its 35 arcuate movement until it strikes the type wheel 1I.

It will be seen that the action of the roller and the stud forces practically all of the power to initially lift the ribbon elevator. The hammer 40 is then started slowly in its travel toward the typewheel, the speed being increased until the roller leaves the stud and the hammer completes `its stroke. In this way the ribbon is raised up in front of the type wheel while the printing hammer 45.

is caused to strike the ribbon forcing it against the paper causing the type wheel to impress a character on the paper.

The relative positions of the various parts of the units just described are best shown in Figures 5 and 5A.

The ribbon and the printing mechanism is preferably located centrally and in front of the paper carriage. The ribbon elevator 35 and the armature 301 spanning the paper roll |52 on the 55 carriage bringsthe ribbon and the hammer in close proximity of the typewheel as will Vbe seen by reference to Figure 5A.

The control of the electric circuit to the mag-` nets 300 will be hereinafter fully described.

Motor apd'line switch Included in the machine is amechanisin for the switching on and ofi, of the motor, the switching of the line circuit to the sending, receiving and stopped condition, and a. time' limiting or time delay action for stopping the machine automatically after a. predetermined time period has elapsed. This unit'is power driven withthe exception of the two manually loperated buttons provided at i the right and is controlled by the'buttons, the two magnets and paper carriage. .l

The power employed to drive the machine is preferably an electric motor..- Suitable switches 'are provided to start and stop the motor at times 75 desired so that the machine does not operate continuously but is always under the control of the operator who may be at any machine of the system. The motor switch heretofore referred to is of the toggle type, and the switch blade is operated in one direction by the motor and is returned by a spring. We have arranged preferably two L-shaped levers 3I0 and 3II which are supported on a common pivot 3I2, one of these members extending upwardly and to the right while the other member extends upwardly but horizontally in the opposite direction. The L- shaped lever 3 I 0 is provided on its lower end with an insulator portion upon which is fastened a contact plate 3 I 3. When in the operative position shown the contact plate 3I3 engages two fingers 3I4 completing an electrical circuit through the fingers 3 I 4 to the motor.

The right hand portion of the Lshaped lever 3II is tapered downwardly to insure engagement with thearmature 3I5. Disposed at equal distances between the ends ofthe Lshaped levers 3 I0 and 3 I'I are preferably pins 3 I 6 and 3I1 which support a spring 3I3 in its stretched position. The function of the lever 3| I is to raise the spring 3I8 upwardly until it passes above the pivot 3I2. This action will give to the lever 3III a snapping upward movement and if the lever 3II is lowered so that the spring 3I8 passes below the pivot stud 3I2, the Lshaped lever 3| will be snapped down into contact with the fingers 3I4 again.

The vertical section of the Lshaped lever 3II extends above the periphery of the gear 3I9. Carried on the face of the gear 3I3 is a pin 320 which is carried around as the gear 3I9 is rotated in the direction of the arrow and which is capable of striking the Lshaped lever 3| I and moving the same to the left until the pin passes over the end of the Lshaped lever 3II. As the pin 320 moves the Lshaped lever 3II to the left, the horizontal section of the Lshaped lever 3II will be raised on its pivot 3I2 above the armature 3I5. The end of the bevel portion of the Lshaped lever 3l I then passes into the notch in the rmaf ture 3I 5 and the armature 3I 5 will be drawn over by the spring 32| and caused to pass under the lever 3II locking the same in this position. Simultaneously the pin 320 on the gear 3I9 passes the point of contact with the Lshaped lever 3l I. This operation opens the motor switch and it is locked by the armature 3I5.

Carried by the main frame of the machine and the Lshaped lever 3II is a spring 322 which is secured to the Lshaped lever near its bevel end. The function of the spring 322 is adapted to draw the Lshaped lever 3II downwardly when it is released by the armature 3I5.

The armature 3I5 is operated by energizing the magnet 323. When the armature is moved to the right it will release the Lshaped lever 3II which will be drawn downwardly by the springr thereby closing the switch. The movement of the Lshaped lever 3I0 in opening and closing the switch also operates the contacts 324 through the insulating stud 325. In opening thev switch only the Lshaped lever 3I0 operates a horizontal bar Y 326. The function of the bar 323 will be hereinafter more fully described.

Associated with and driven by the motor is a gear 321 and a train of gears, 328, 329, 330, 33|, and 332, the ratio of these gears being such as to give a predetermined reduction in speed between gears 328 and 332. The driving gear 321 being engaged directly with the gear 328, any operation caused by the gear 323 will be fairly fast relatively to the speed of the gear 321 and any function caused by gear 332 will be much slower depending upon the gear train ratio selected for a denite interval of time. r

Disposed directly in front of and below the axis 45 of the gears 328 and 332 are two gears 3I9 and 333 all of equal size. These gears are intermittently meshed with the two driving gears 334 and 335 and are driven when so meshed by the companion gears 328 and 332. As the three sets of 10 gears referred to above operate in a similar manner their locking and releasing operations are alike. The functions of gears 323, 3I3, and 334 will now be described.

Gears 328 and 3I9 are mounted on parallel 15 axes. of rotation, each facing the other with a slight clearance between them so that when the gear 334 is brought into mesh with the two gears 328 and 3I9, by swinging on the pivot 336, the lower gear 3I9 is driven by the upper gear 323 20 through the gear 334 as best shown in Fig. 7A. It will be seen that gear 3I9 receives an intermittent rotary motion by being meshed or unmeshed with the gear 334. Relative spacing of the gears 328 and 3I9 is important in this oper- 25 ation. It will be seen that if the gears were in alignment and the gear 334 was in engagement with the gears 328 and 3I9 the angle of the teeth on these gears when in contact with each other, and when power is applied to gear 328, and a 30 loadapplied to gear 3I9 the idler gear 334 would be forced out of engagement with the other gears 328 and 3I9. Should the centers of the gears 328 and 329 be spaced a given distance apart the angles of the teeth on the gears, relative to each 35 other, would be in opposite order and the idler 334 would be drawn closer between the gears 3I9 and 328 and ultimately locked in this position while power was applied to gear 328 and a load maintained on gear 3I9. 40

Any action of this kind by the gears 328, 3I9, and 334 is overcome by spacing the driving and the driven gears in such a manner as to bring the angles of contact between the teeth of the gears and of the idler into substantially parallel 45 planes. This results in the idler gear when released. meshing with the gears 328 and 3I3, and remaining in meshed position until the load is removed or the gears unmeshed. The difference in the angle of contact of the gear teeth is sub- 50 stantially zero and the slight locking which takes place is not to such an extent as to render the separation of the gears difficult.

When the gear 334 is meshed with gears 328 and 3| 9, it is necessary that the idler gear be 55 come properly meshed with both Athe gears 3I9 and 328. 'I'his action is assured by placing the arc through which the center of the gear 334 travels at such position that the gear 334 will always contact with the driving gear 328 first which will draw the idler gear 334 into mesh with the driven gear- 3I9. Gear 334 is loosely journaled in the upper end of a bell crank lever 331 winch is pivoted-ito the main frame at 336 and swung to the left by a spring 333 and in the opposite direction by' a pin 339 carried onthe bar 326.

The bell crank lever 331 is beveled at the end of the horizontal-section which is engaged by the armature 343. The armature normally holds the 70 bell crank lever 331 in` a position dlsengaging gears 334 fromgears 328 and 3I9. Should thelever 331 be released by the armature 340 at a time whenv themotor switchv is closed and gear 328 is being rotated the spring 338 on the bell crank lever 331 will bring the gear 334 into mesh with the gears 328 and 3I9. Gear 3I9 will now be rotated inthe direction of the arrow, carrying the pin 320 around into contact with the upper end of leverv 3l I. Continued rotation of gear 3I9 will open and lock the motor switch as heretofore described and simultaneously the vertical section of the lever 3I0 strikes a pin on bar 326 shifting the bar to the right. 'I'his movement of the bar 326 by means of the bell'crank lever 331 disengages the gear 334 from its companion gears. Bell crank lever 331 will be locked in this position by the armature 340 and the spring 34|. In

this mannerthe motor switch can be closed byA energizing magnet 323 and is opened by energizing magnet 342. I

Referring more particularly to the time limiting feature for the opening of the switch which functions substantiallythe same as the motor switch proper, in regard to intermittent drive by the gear train, through the idler gear 335 and gears 332 and 333. The idler gear 335 is carried on a vertically disposed lever 343 which is pivoted at its lower end 44 to the machine frame and extends upward in line with the fixed rack 200 on the paper carriage II. The lever 343 retains the gear 335 inV engagement With gears 332 and 333 by the action spring 346 during the time it is not in contact with the rack 230, or shifted to the right by the pin 341 on the bar 326. The engagement of gear 335 in mesh with gears 33 2 and 333 slowly rotatesgear 333 at this end of the gear train at a reduced speed in the direction of the arrow.

Upon the face of gear 333 a stud- 348 is carried which is held against a stop lever 349 by means of preferably the spiral spring 350, one end of which is attached to the pin 348 in the gear wheel 333 while the other end is secured to the stationary bearing 35| upon which the gear 333 rotates. It will be seen that should the gear 333 be turned in a clockwise direction and released, it will be returned to its normal position with the pin 348 against the stop lever 394 by the spring 350. Rotation of the gear 333 far enough, will cause the pin 348 on this gear 333 to strike the upper end of lever 352, piyoted at its center to the main frame of the machine, thereby contacting its lower end to operate the armature lever 349 to the right.

Operation of the armature 340 by the lever `352, will release bell crank lever 331 thereby opening the motor switch as heretofore described.

With the operation of the switch lever 310, the

bar 326 is shifted to the right and the pin 341 in the bar 326, to the left of lever 343, will shift lever 343 and, in turn the gear 335 out of engagement with its associated gears. As soon as gear 335 is released from gear 332, gear 333 will be returned bythe spring v35|! to normal position, and gear 335 will be held out of engagement with gears 332 and 333 as long as the motor switch is open. It will be re-engag'ed with gears 332 and 333 the moment the switch is closed provided the paper carriage is not in the starting position.

Each time the paper carriage isreturned to starting position by the motor, the rack ZIIIIwill strike the lever 343 and dis-engage the gear 335 from gears 33,2 and 333 yallowing th'e gear 333 to return tonormal position. The motor has now been started by the operation of the motor switch and consequently the switch member 3III will release bar 326 and the spring 353 will lmovepthe bar 326 to the left. The lever 343 is then releasedv by the pin 341m the bar 326 and thegears .332.,

333 and`335 4are meshed and slowly rotate kthe gear 333.

Assuming that the rotation of gear 333 will bring the pin 348 into contact with the member 352, thereby opening the motor switch at the 5 end of a iive minute period of time for example, if return of the paper carriage does not take place during this time, and the machine will be automatically stopped. However, if carriage is returned to its starting position at any time during this-five minute period of time, the carriage will strike the lever 343; the gear 333 will be returned again to its normal position. 'There is preferably a five minute interval of time between the last operation of the carriage, the starting of the machine, and the moment when 'the machine will be automatically stopped. The machine will continue to run, if the. printing is not stopped, for a greater period of time than that for which the time limit mechanism is set. The interval of time for which the automatic operation of the motor switch is set can be varied by changing the distance between the pin 348 and the stop lever 349.

Any suitable means may be provided to mount the pin 348 so that its position may be' adjustably 25 varied by minute amounts. A parallel motion is given the bar 326 by pivotally supporting it on preferably two links 354 and 355 at each of its ends. These links are pivoted upon the frame of the machine. Mounted upon the same pivot journaled with link 354 is a hooked pawl 356 with three extension arms, the lower arm being turned at its extremity at substantial right angles to and in alignment with the link 354 and the end of the upper arm `being in co-operative relation with the button 351. Both the bar 326 and the pawl 356 are operated in one direction by the spring 353. When the bar 326 is moved to the right, the link 354 will raise the hooked-end of pawl 356. The pawl 356 can also be operated by the button 351 without rocking the bar 326.

Stopping the motor will shift the bar 326 to a right hand position accordingly releasing gears 334 and 335, and raising the hook on the pawl 356 above and clear of the upwardly central projecting contact 358 in the group 359. The right hand contacts in this group will be closed and the left hand contacts will be opened. As described in another part of the specication, closing the left hand contacts of group 359, completes the line circuit through magnet 323 and the line battery. Energization of magnet 323 by the line battery operates the motor switch.

'I'he contacts of group 359 are operated by the starting button 360, which, when pressed into engagement with the long contact spring 358 will bring theend of the spring in engagement with the hooked end of the pawl 356 and simultaneously with the moment of contact between the springs, the motor switch will operate to allow the hook on the pawl 356 to drop and hold the contacts in position shown in 8A while the start button 360 is released.

The contacts are held in this position as long as the machine is operating as the transmitting 65, machine. This position is also maintained until the contacts 359 are released by manually actuating the transfer button 351 which connects the machine for receiving only, or when the motor switch is operated by other means as mentioned otherwise. Figure '1A is a side View of the idlers 334 and 335 and their companion gears. A full detailed description of operation of the complete unit in co-operation with the rest of the machine has been given in another ification.

Line circuit and operation The two line circuits are best shown in diagrammatic views Figs. 8 and 8A. Fig. 8 has one line relay which energizes a secondary circuit of the machine when sending and receiving, while Fig. 8A has a separate line relay for sending and for receiving which will be hereinafter more fully described. The use of two relays is advisable in cases where there is considerable leakage in the circuit between two machines, as the individual relays can be adjusted to suit the condition under which they would function when used for one operation only.

The source of current is preferably at the transmitting end of the system. The relay at this end is subjected to varying operating characteristics different from that of the receiving relay at the opposite end of the line.

portion of the spec- Only in cases of extreme line leakage is thet circuit of Fig. 8A necessary. The operation is the same in both circuits with the exception of the dividing of the incoming and outgoing impulses between relays 36| and 362 in Fig. 8A. At 363 and 364 is represented the line terminals of the machines when they are connected. Dotted lines representing line circuit conductors 18| and 182 1 interconnecting the circuits of Fig. 8 and Fig. 8A,

indicate how two machines comprising transmitting and receiving elements may be interconnected by line conductors. Either of the machines may bek of the two-relay (Fig. 8A) or one line relay (Fig. 8) type.

The transmitting and receiving circuit is completed through the two machines. When a machine is not in use, the circuit can be traced as follows; from terminal 363, through conductor 365, motor switch magnet 323, conductor 368, contacts 324 and 361, conductors 369 and 318, contacts 359 and 358 and then from conductor 313 r to terminal 364. This is the normal circuit when the machine is idle. Should current now be supplied to terminals 363 and 364 from another ma.- chine, the trip magnet 323 of the motor switch will be energized, the insulator portion 325 of the motor switch will reverse contacts 3|3, 361, and 324. Reversing the contacts of group A will complete the circuit for receiving, from conductor 365 through conductor 316, contacts 3|3 and 361, conductor 368, line relay 36| and conductors 311 and 318, as heretofore described.

The contact group A short circuits the line relay 36| and closes the circuit through trip magnet 323 when normal, and the reversal of the group A by the motor switch short circuits trip magnet 323 and closes the circuit through the line relay 36|. When current is supplied to the terminals at this time, the line relay 36| will be operated by the received impulses and will close a local circuit in the machine.

Reviewing the foregoing when the machine is idle, trip magnet 323 is connected into the line circuit, and an incoming impulse will cause the trip magnet to release the motor switch, starting the motor and the machine; the switch 361 will cause rei ersal of the contact group A, short circuiting the trip magnet 323 and finally connecting into the circuit line relay 36|.

The resistance of magnet 323 and relay 36| being the same and switching arrangement makes it possible to change from one function to another without any change in the loop resistance of the line circuit, and two or more .machines can be switched in or out of the line circuit without' a change in the value of the line resistance.

The line circuit and `its equipment, as just described, applies to the machine acting as a receiving machine and being controlled at one end 5 of a circuit by a transmitting machine at the other end ofthe circuit. At the transmitting end, the circuit through the machine, when in operation, differs from that of the receiver because the transmitter unit mus't be included in 10 the circuit. The setup and operation of the circuit and apparatus'in the transmitting machine follows, when two machines are connected together, but idle, the line complete through the trip magnets 323 of each machine. When it is 15 desired that the machines be started, current is supplied to the line momentarily to operate the motor switch trip magnets 323. This is accomplished by the operator pressing the start button 368 which must be operated to its limit vof 20 movement thereby opening contacts 358 and 359l and closing 312, 358, and 319.

The line circuit is now complete in both machines from terminal 363 through conductor 365, trip magnetv 323, conductors 380 `Vand 368, con- 25 tacts 361 and 3|3, conductors 369 and 395, line battery, conductors 39| and 392, contacts 312 and 358 through conductor 313 to terminal 364,. The current from the battery 314 will operate the trip magnets of both machines and, the motors 30 will be started.

In the receiving machine, only the reverse operation of the contact group A will occur when the motor switch operates, but at the transmitting machine,together with the operation of the 35 contact group A, the pawl 356 releases the hookedend so as to overlap the upper end of contact 358. When the pressure is removed from the button 368 the spring contact 358 will engage the pawl 356, openingcontacts 312 and 319 but keeping 40 contacts 319 and 358 closed. The contacts 312 and 319 when closed, short circuit the open contacts |32 on the key transmitter completing the line circuit through the battery, but when the button is released and the pawl 356 engages the 45 contact spring 358, as shown in Fig. 8A, the transmitter contacts |32 will be connected in the line, from terminal 363 through conductors 365 and 316, contacts 361 and 324, conductor 368, relay 36| conductor 395, battery 314, conductors 39| and 50 396 to the transmitter contacts |32, from consame both for the sending and the receiving ma- 55 chine, but the transmitter contacts and line battery are connected into the line circuit at the transmitting machine. When two complete machines are connected to a line, either machine can be set up as a transmitter or receiver dee0 pending upon which of the machines the starting button 368 is pressed. The-transfer button, 351 makes possible the quick change in the line circuit from transmitting to receiving while the machines are running. When the machines are 65 in operation but the transmitter keys of the sending machine are not being operated, the transmitter contacts |32 remain open thus opening the line circuit. If while a message is being received from the transmitting machine should the 70 l receiving operater desire to stop the transmission of the message, the starting button 388 is pressed.

This, through its contact group B opens the line circuit at the contacts 899 and 359, at the receivvcircuits in Figs. 8 and 8A aresimilar except as tothe relay 36| which is reversed with respect to conductor 395 as shown in Fig. 8A. The relay 362 being added to the conductor 398 in the circuit oi Fig. 8A. In this arrangement, relay 36| is short circuited and relay 362 operates inthe transmitter circuit when sending, and when receiving, relay 36| is connected inthe line circuit and relay 362 is connected in the open trans mitter circuit. The machine is stopped by sending la particular series of impulses over the line circuit by the transmitter which operates magnet 342 (Fig. 7) indirectly causing the motor-switch to open. In Fig. 8A, the contacts or relays 36| f and 362 are preferably placed in multiple.

The opening of the motor switch, through the insulator 325 reverses the contact at A and releases the pawl 356 causing reversal of contact B. It is apparent that the opening of the motor switch puts the line circuit and apparatus in vits normal or inoperative position ready for the lably divided into three divisions viz; the line circuit that has heretofore been described, the rst secondary circuit that is controlled directly by the contacts of the line relay, and the second local circuit that is controlled by the contacts of the slow release relay and the cam or armature operated contact groups. The first secondary circuit is best shown in Figure 9, in heavy lines `and designated circuit ,A. The other circuit is shown in light lines and designated circuit B.

The power supply for the local magnets is received from-the generator 401 coupled to and driven by the motor, not shown, which has been heretofore mentioned as the source of driving power for the machine. The line relay through the conductors 400 and 40| receives the impulses set up by the transmitter, and throughthe energizing of the armature 408 to swing contact into closed or opened.position with relation to the second circuit through the magnets 88, 81 and ||4 and the generator 401 in unison therewith.

Magnet 88 oscillates ilnger 19 on long impulses only. Relay magnet ||4 -is rendered slow-releasing by short circuiting one or more turns of its winding, or otherwise, and functions to keep the second local circuit open during the reception of a series of impulses.

The second circuit can be traced from the line 'relay contact 63 through conductor 4|3 circuit A to conductors 408 and 409 where it is -divided intoa multiple circuit throughmagnets 88 and 81. Conductor 4|0 connects magnet 88 and the slow release relay ||4 through conductor 4| generator 401 and conductor 4|2 to armature 403 of the line relay. A combination of impulses from lthe transmitter to the line relay 402 will set up a like series of impulses in the local circuit, all impulses operating magnet 81 and allowing the typewheel to advance one division for each impulse. All long impulses will operate magnet 88 which shifts the escape finger 19 and rotates the typewheel 1| the same or a greater number of divisions than does the magnet 81, and also controls the channel position of the typewheel 1|.

Relay ||4 is also ailected by all the impulses. but due to its slow releasev action it wi1lrema.in operated during the reception of a series of impulses keeping the second local circuit open during this period and stopping the printing or 10 other functions. During the time when no impulses are being received, cam |09 keeps the armature ||3 in operative position, opening the second local circuit through contacts ||2. The foregoing actionvsaves time and the operation is 15 more positive. The armature I3 is always in the operated position when the first impulse of any series energizes magnet ||4 and it is only necessary that the armature be held in this position during the rst impulse by cam |09, the re- 20 mainder of the series holding armature in attracted position through magnet ||4.

Cam |09 only engages the armature arm ||l at the first division of the typewheel 1| and the iirst impulse of any series moves the cam |09 25 l after the last impulse is over the armature ||9 $5 closes the second circuit through contacts ||2 and the printing and restoring take place. In the embodiment `of our invention herein described, the proper operation of the magnets is thus largely dependent upon the speed at which 40 they may be actuated or released, and in this connection it is well to note that the magnet 81 is fact in actuation and. responds to all impulses, while the magnet 88 is slow in actuation and quick in releasing and. responds only to the 45 long impulses. The magnet 88 is in series with the slow relay magnet ||4, whose armature may also be operated mechanically by cam |09, and is slow releasing when magnetically operated. Due to the mechanical construction of the arma- 50 ture 84 and the retardlng eiect of the slow relay magnet ||4 in series with-magnet 88, it responds only to prolonged impulsesthrough magnet 88 and releases quickly when the current is cut off.

When no impulses are being received, the ar- 55 mature of relay ||4 isheld up by cam 09, and the first impulse disengages the cam and` frees the armature, the armature still remaining in that position as long as the impulse, or series of impulses continues, All other magnets are made 60 to operate or release as rapidly as is possible.

The sequence of operation of the several magnets is as follows: the closing ofthe line relayA contact will send impulses through magnet 81 and slow relay ||4 and magnet 88. If the im- 65 pulses be short, magnet 81 will only operate and if long, magnets 81 and 88 will operate in the sequence. The slow relay will hold yits contact open during the series of impulses. The operation of magnet 81 will only advance the type- 70 wheel one division for each impulse and the operation of magnets 88 and 81 together will ad-v vance the wheel one or more divisions per impulse. In any case that the operationl ot both magnets advances the wheel only one division 75

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