US2405297A - Telegraphic printing apparatus - Google Patents

Description

Aug. 6, 1946. c. J. FrrcH TELEGRAPHIC PRINTING APPARATUS Filed March 1'7. 1945 3 Sheets-Sheet 1 Ag.' '6, I19m c. J'. 'F1-TCH 2,405,297

TELEGRAPHIG PRINTING APPARATUS Filed March 17, 1945 :s sheets-sheet 2 i FlGyS.

1 11T "in INVENTOR CIJ. FITCH ATTORNEY Aug. 6, 1946. c; J. FrrcH 2,405,297

TELEGRAPHIC PRINTING APPARATUS s sheets-sheet s I 2 CMF/72TH /00 v BY lATTRNEY having a standard typewriter keybo-ard.

Patented Aug. 6, 1946 TELEGRAPIJIIC PRINTING APPARATUS Clyde J. Fitch, Endicott, N. Y., assigner to International Business Machines Corporation, New York, N. Y., a corporation of New York Application March 17, 1945, Serial No. 583,227

11 Claims.

ThisI invention relates to va control mechanism capable of operating a telegraph printer having a larger number of keys than can be selected by all the possible different combinations of the code used.

On many commercial telegraph lines, a five unit code is u-sed, known as the Baudet code. This code affords only thirty-one usable combinations, which is not enough to operate a page printer Accordingly, a particular object of the invention is to provide a control mechanism capable of opw erating in response to five unit code, te control a 'printer having a capacity equivalent 'to a standard typewriter keyboard, including both capital and small letters. K

Other objects of theinvention will be pointl ed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. l is a diagrammatic View of a tape reader for reading the perforated tape.

Fig.- 2 is a vertical sectional view of a portion of a telegraph printer which may be operated under control of the tape reader shown in' Fig. l.

Fig. 3 is a vertical sectional view of a portion of the permutation mechanism by means of which the keys of the printer are selectively operated.

Fig. l is a detail View of the carriage return key.

Fig. 5 is a' section of tape illustrating the iive unit code employed.

' sprocket I "l, and thence to a take-up reel (not shown). The tape feeler I2 is adapted to open contact TC if tension on the tape fails. In the sensing pin guide block are five sensing pins similar to the one shown at I5 in Fig. 1: The

' sensing pins are distributed across the tape in line, respectively, with the iive different code positions I, 2, 3, Il, 5 (Fig. 5). Associated with each sensing pin is a pin contact, suchas the contact PCS, comprising a stationary contact spring I6 and a movable contact spring Il having an insulating rod I8 at its end bearing upon the end of the related sensing pin I5. During certain times in the cycle of operation of the tape reader, the sensing pins are allowed to move against the tape, under the action ofthe `movable contact Fig. 6 is a timing diagram of the tape reader .L

contacts.

Fig. 7 is a diagram of the keyboard ofthe Y printer.

Fig. 8 is a circuit diagram of the entire apparatus.

A telegraph printer .control mechanism inv aci cordance with the invention maybe operated directly from signals. received telegraphically, or by means of a perforated tape. For the purpose of illustration, a tape controlled telegraph printer Y is shown in the present application. The tape may be one prepared bya telegraphic receiving punch operating in response to signals from a tape transmitter controlled by a tape prepared by a typewriter tape punch, of the kind shownin my copending application Serial No. led March 8, 1945.

The tape reader` roller vI I, a tape feeler and guideIZ, through the slot of a sensing pin guide blockA l3, over .a

. 55 The tape reader shown in Fig.. l is similarto springs. Those sensing pins which nd a. hole in the tape move far enough to permit the contact points on the contact springs to engage. The different pin contacts will later be referred to as PCI, PC2, PCS, PC, and P05.

'Ihe sensing pins are controlled by a 1in I9 on a shaft2, which extends to the rear, as representedY by the dot and dash line 2U', and has vfixed toit a three-armed lever 2 I. The leitwardly directed arm of the lever 2l carries a roller 22 at its end bearing upon a cam 23 xed to a shaft 2fl,.which extends to the rear as indicated by dot and dash line 24', and has fastened to it a pulley 25 constantly driven by a motor RM through v a belt 27. The rightwardly directed arm of the lever is normally latched by an armature plate Sil pivoted at 3l and pulled toward the left by a spring 32. A latch magnet LM is energized, in a manner to be described, to withdraw theV latch plate from the arm. When this occurs the arm rocks clockwise, then counterclockwise, following the contour of the cam 23. When it rocks clockwise the fin I9V releases the sensing pins and allows them to engage the tape. When it rocks counterclockwise, the pins are withdrawn from the tape.`

The ,tapefeed sprocket shaft extends to the rear, as indicated by dot and dash line 33', and

has fixed toit agfeed ratchet wheel im'. atingwith the ratchet wheel 3G is a feed dog articulated toan arm St, which is iixed to a pivot shaft 37. The arm 36 has journaled upon it a roller-38 bearing lagainst a second cam on the shaft 24. Normallythe arm 36 is latched by means of an arm lil extending rigidly from the pivot Yshaft 3l .and overhanging a latching dog lII pivoted at 42 on the upwardly extending arm ofthe lever 2I. When the latch magnet is energized and the three-armed lever 2l rocks clockwise, the latching dog 4I is removed from the ann 40 and the feed arm 36 is allowed to rock clockwise, under a pull of spring 43, following thel contourvof cam 39, then counterclockwise, as the'high part of the cam passes lunclerfthe Cooperanimee? small roller 38. The first movement allows the feed dog to ratchet over a tooth of the ratchet wheel, with which it is held in contact with a spring 44. The second movement of the feed arm feeds the ratchet wheel forward by one tooth, at the end of which movement the dog engages a cam block 45, which limits its movement and also locks the feed ratchet wheel against overthrow. The shaft 33 also has fixed to. it a toothed detent wheel 49 with which Vcooperates a small roller 45 on a detent arm 41 pivoted at 48 and pulled downward by a spring 58. The latching dog 4I is urged in counterclockwise direction about its pivot 4.2 by a small spring 5I, so that a pin 52 thereon normally engages the upper end of the arm 2I. As explained in the above mentioned Patent 2,320,788, the timing is such that the three-armed lever 2k! is restored to normal positionn before the feed arm 35 completes its feed stroke. Consequently, the latch dog 4I first strikes the end of the latch arm 4D and does not move under the latch arm until the end of the feed stroke.

The shaft 2 4 also has fixed to it five contact operating cams 5 5, 56, 51, 5.3 and 59 with which are associated, respectively, five contacts CI, C2, C3, C4, C5, to be referred to later in connection with the circuit diagram.

The printer The illustrative machine comprises a typewriter having a keyboard 6,8 (Fig. 2), the keys of which are subdivided into two zones, as indicated by the dot and dash lines Fig. 7. Zone 1 includes all of the letters of the alphabet, except the letters 7c and l. Zone 2 includes the letters lc and Z, the numbers, the'IAB key and various symbols and punctuation marks. .In addition, the keyboard includes a carriage return key, an upper case. key, and a space bar, these keys being outside of both zones.

As shown in Fig. 5, the twentyfiour letters. of the alphabet in zone 1 use the standard Baudet code combinations. This is also true4 of the space, carriage return, .line feed. figuresV shift (upper case) and letter shift (lower case).. The .code combinations formerly used for letters lc and l, are used, respectively, for thefzone 1v and zone 2 shift signals. rEhe zone shift signals occur when4 there is a transfer from one zone to the otherfthat. is to say, when a zone 2 character follows a Zoner l character, the Zone 2V shift signal will be inserted between them, and when a zone lcharacter folbut is normally restrained by a stop 1I on a lever 12 pivoted on the bell crank B5, which stop normally stands in the path of a lug 18 on the cam. When the lever 12 swings to move its stop 1I out 'of thepath of the lug 13, the arm 18 swings the cam into engagement with the poweryroller, to be actuated thereby, to swing the bell crank 55 to actuate its connected mechanism.

The lever 12 has an arm 14 which is provided with van oiset projection at its end, which projects laterally through an opening in the bell crank lever 65 and between the tangs of the bifuroated lower end of an arm 15 of the key lever 18 pivoted on the common rod 11. Depression of the key lever will rock the lever 14 and release the cam 64 as described.

Each key lever 16 is connected by a link 1.8 to

a related control lever 19 pivoted on a common rod 80 and urged downward by a spring 8l against a set of six revoluble permutation bars 82, bearing the individual numbersl, 2, 3, 4, 5, 5. In line with the control lever 19. the permutation bars have slots 83, the slots on the bars I, 3 and 5 being on the top side, while those on the bars 2, 4 and 6 are on the bottom side. If the bars 2, 4, and 6 are revolved while the bars I, 3 and 5 remain stationary, all the bars will present slots to the particular control lever i9 shown in Fig. 2, which will therefore rock downward under the inuence of the spring 8 l, actuating the related key lever 16. The arrangement of the slots 83 aligned with each of thecontrol levers 19 is different, so that by rotating different combinations of the permutation bars 82, diierent keys will be actuated.

The driving and control means for the selective rotation of the permutation bars has substantially the same construction as disclosed in Patent 2,165,247. Under the permutation bars is a drive shaft 85 driven by a motor (not shown). The shaft 85 has a driving gear 86 fixed to its left end and a similar gear at its right end, which does not show in the drawings. The gear 85 meshes with a gear 81' fixed to a short shaft 88 journaled in bearings 88, so as to be concentric to permutation bar 3. The gear 81 meshes with gears 90 and QI fixed to short shafts (not shown) similar to the shaft 88, but concentric to the permutation bars I and 5, respectively. At the oppolows a zone 2 character, the zene l shi-ft signal erating its keys of the kinddisclosedin Patent :Y

2,165,247.- The type bars (notshmvn) are-actuatedby a power driven roller 65. A cam 64 is provided for each type bar and each cam is journaledon one arm of a related bell crank -lever pivoted on a stationary rod 56, the otherv ar-rn of` the bell crank'lever 15S-being operativelyA connected with one arm ofV a related bell crank lever 51 by means of a link 68. IThe otherA armor lever 61V isA connected yto the Arelated type vbar` (inet shown) AinA well known mannen (see Patent The lever 65 is actuated by ythev cam 64 when the latter is made to engage the driven -rol-lerli` by operation o-a related key lever 15. The car-n 64 is engaged by a springpressed armf 10 which Y.

tends to turn it into contact with the roller 63,

site end of shaft the arrangement is similar but the gear corresponding togear 81 is xed on a short shaft concentric to permutation bar 4, while the gears corresponding to gears 98 and SI are fixed to short shafts concentric to permutation bars 2 and 6.

The short shaft 88 has fixed to its inner end a ratchet toothed drive wheel 82 positioned to be engaged by a tooth 93 on a sliding dog 94 of a clutch 95 mounted onthe end of the related permutation bar 3. As more fully disclosed in Patent 2,165,247, the engagement of the tooth 93 is controlled by a bell crank lever 96 pivoted at 91 and having an armature S8 attached thereto operated by a code magnet M3. Each of the other short shafts similar to 88 has the same kind. of clutch means for connecting it to the related permutation bar. There are nve additional code magnets, to be referred to later as MI, M2, M4, M5, and M5, controlling-the respective clutches.

The arrangement of the slots 88 in the permutation bars is such that rotation-of different combinations of the permutation bars releases differ.-

ent keys for operation. All of the keys in zone 2 require rotation of the No. 6 permutation bar, while all the keys in zone l require this bar to remain stationary. This permutation bar, therefore, acts as a zoning member, to route the signals to the different zones. The control levers which respond to the carriage return code, the line feed code, and the space code are cut out over the No. permutation bar, so that their operation will not be affected by it. For the rest of the permutation bars, the arrangement of the slots is indicated by the respective ve position code combinations of the tape in Fig. 4, that is, a hole in the tape will always cause the related permutation bar to rotate; therefore, the appertaining slot will face downward.

A shift solenoid SHS (Fig. 2) has a plunger 02v articulated to a lever 93 connected by a link 94 to the upper case key UC. The key UC operates a basket shift mechanism (not shown) similar to that disclosed in Patent 1,945,097. Accordingly, when the solenoid SHS is energized, the type basket shifts to the upper case position and remains in that position until the solenoid is deenergized, when it shifts back to lower case position.

Fig. 4 shows a detail of the carriage return key CR. The lever a of the key CR is overhung by a flap 06 on a keyless lever 15b. The key lever 16a is associated with a cam mechanism for operating a carriage return mechanism such as shown in Patent 2,104,559. The cam mechanism is similar to those shown in Fig. 2, except that the cam is of single lobe shape, instead of the double lobe shape of cams 60. The lever b has no cam mechanism of its own, but acts through the key lever 16a. Each of the levers 16a and 1Gb has a control lever 19 (Fig. 2) connected to it by a link 18. The control lever for the key lever 16a re- Sponds to the carriage return code 4, while the control lever for the keyless lever `15b responds to the line feed code 2.

Operation Referring to Fig. 8, the apparatus comprises a typewriter represented by dot and dash lines 90, a tape reader represented by dot and dash lines 90, and a relay gate located therebetween. When lthe apparatus is plugged to a source of power,

tion. When the tape has been inserted in the tape reader, the machine is started by pressing the start button STR. The cams operating cam contacts CI-C5 are continuously running whenever the motor RM is in operation. When contact C4 closes at 45 (Fig. 6), a circuit is completed from wire |00, through said contact, wire |02, the start contact STR, the pick-up coil of relay R21 to wire IOI, energizing said relay. Contacts R21c close, completing a circuit through the holding coil of relay R21 from wire |00, through tape contact TC, which will be closed whenever the tape is present with the proper tension in the tape reader, stop contact STP, contact R21c, the holding coil of relay R21, to the wire |0I. The contacts TC and STP are shunted by the contact CI, which opens between 210 and 316 of the cycle to test the holding circuit of relay R21.

Contacts R211) and R21c close, preparing the circuit of the latch magnet LM and the circuit to the permutation code magnets IVM-M6, respec- Ytively. At 333 the cam contact C5 closes, completing a circuit from wir@A |00, through said contact, the latch magnet LM, a series of normally closed contacts RISC, RItc, R|1c, the contact R21b, resistance |03, to wire IOI, energizing the latch magnet. The armature 30 (Fig. 1) releases the three-armed lever 2|, which rocks clockwise, allowing the tape feed dog 35 to ratchet back over one tooth of the wheel 34 and the sensing pins to test the tape between 33 and 246 of the following cycle. After the sensing p ins have been withdrawn from the tape by the clockwise rocking of the three-armed lever 2|, the feed dog 35 feeds the tape one step. The latch magnet LM will now be energized each time the contact C5 closes, near the end of the cycle, so long as the latch magnet circuit remains prepared. During this time the step-by-step tape sensing and tape feeding will continue.

It will now be assumed, to take the simplest case first, that the machine has been in operation in zone 1 and another character in zone 1 is to be printed. Suppose it is the character a, having the code 12. At 33 the sensing pins test the tape. At 45 the cam contact C4 closes, .completing a circuit from wire |00, through contact C4, the pin contacts PCI and PC2, the pick-up coil of code relays RI and R2, to wire 10i, energizing said code relays. Contacts RIa and R2a close and at 81 cam contact C2 closes, completing a holding circuit from wire |00, through contact C2, contacts RI a and R264, the holding coils of relays RI and R2, to the wire IOI. Conv tacts Rlb and R22) close and at 144 contact C3 closes, completing a circuit from wire |00, through contact C3, wire |00, the series of normally closed contacts Rita, RISa, Rl2a and RIIa, the contacts R21c now closed, contacts RIb, R25, normal contact R201), and code magnets M M2 t0 wire I0 energizing said'code magnets and causing the printer to print the letter a. Y l Y At 207 the contact C4 opens, followed by the opening of the pin contacts PCI and PC2 at 246'. At 250 cam contact C3 opens, deenergizing the code magnets MI- and M2 and at 335 cam -contact C2 opens, dropping out the code relays Ri and R2l and restoring the circuit to normal condition. f l

Zone 2 shift-Before the first character code of every message there will appear a zone shift signal. Suppose-the zone shift signal at the beginning of the message is thezone 2 shift signal 25 followed by the code 24, representing the number 5. When the sensing .pins sense the zone 2 shift signal in the tape, and when the cam contact C4 closes at 45, circuits are completed, as previously described, through the code relays R2 and R5, which will be energized andthen held through their contacts R2a and Ria, upon closure of the contact C2 at 81. At the Asame time, a circuit is extended through wire |05', normal contacts Ric,

transferred contacts R20, normal contacts R30 and R40, transferred contacts R5c, relay Rldto the negative wire I0 I, energizing said relay. Contacts RIlla open, to prevent a circuit from being completed to the code magnets-when the contacts C3 close later in the cycle. Contact RIIbA closes, completing a circuit from wire 100, through'wire |06, contact RI 4b, the pick-up coil of relay RI 9 to the negative wire IOI, energizing said relay. Contact RI9a closes, completing a holding circuit from wire |00, through normally closed contact Rl3b, contact Rla, the holding coil of relay RIS lto the Wire |0I. Contact RIBb'closes, preparing .a'circuitto code magnet M0. At 335 c am conf 7 tact C2 opens, dropping out the relays R2, R5 and R|4. Contact R|4a closes.

On the next cycle, the pins sense the code 24 representing .the number 5. The code relays R2 and R4 are energized in the manner previously described, and the vcontacts R211 and R4b close. At this time the circuits are prepared tothe code magnets M2, M4 and M6, the relay R|0 remaining energized from the previous cycle. At 144, the contact C3 closes, completing the normal circuit throllgh wire |04 and the code magnets M2, M4 and M6 which are energized and cause the printer to print the number 5. As long as operation continues in zone 2, the code magnet M will be energized in each cycle, together with such combinations of the code magnets M|-M5, as the successive code combinations in the tape call for. Any one combination of magnets M|M5 will permit operation of either of two keys, one in zone l, the other in zone 2. Magnet Miiv determines the zone. Thus, so long as the relay R|9 remains energized, al1 signals will be routed to zone 2.

Zone 1 shift- When the first character code representing a character in zone l appears in the tape, it will be preceded by the zone 1 shift signal 1, 2, 3, 4. When the pins sense `thissignal, the relays R|-R4 are energized and, when the contact C2 closes, a circuit is completed through wire |05, transferred contact R|c, contact RZd now closed, transferred contact` Re, contact Rf now closed, normal contact Rf, the coil of relay R|3 to wire |0|, energizing said relay. The contact R|3a opens immediately, breaking the normal circuit through wire |04 and preventing the code magnets from being energized during this cycle when the contact C3 closes. Contact R|3b opens, dropping out the relay R|c, whose contact R|9b opens, disabling the circuit to the code magnet M0. When the contact C2 opens at 335, the relays RI-'R4 and R|;3 are deenergized and contact R 3c closes.

Suppose that the next code sensed in the tape is 24, representing the letter r. When the con,-

tact C4 closes, the relays R2 and R4 are energized. Closure of contact C3 completes the normal circuit through Wire |04 and contacts R21) and R4b to the code magnets M2 and M4, energizing said magnets and causing the printer t0 print the` letter r. It will be noted that, whereas the 24 code previously caused the number 5 to be printed, following a zone 21 shift signal, this time the code 24, following the zone 1 shift signal causes the letter r to be printed. The relay R19 functions as a supervisory means having two stable conditions, between which it alternates in response to the two zone shift signals.

Case shift-Each zone includes upper case characters as well as lower case characters. The upper case characters are reached in the normal way, by operation of the case shift key UC. As in standard telegraph work, this operation is initiated by the so-called figures shift core 1245. When this code is read by the sensing pins, the relays RI, R2, R4 and R5 are energized. When contact C2 is closed, ,a circuit is completed through wire |05, transferred contacts R|c, contacts R2d, now closed, normal contact R3e, contact R46 now closed, transferred contact R5e, coil of relay R|2, to the wire |0|, energizing said relay. Contact R|2a opens, disabling the normal circuit to the code magnets. Contact R |2c closes a circuit directly from wire |08, through the shift solenoid SHS to wire` |0|, energizing Said solenoid, which pulls down and holds the 8 case shift key UC. Also, contact R|2b closes, completing a circuit from wire |06, through said contact, the pick-up coil of relay R|8, to wire |0|, energizing said relay. Contact Rla closes, completing a holding circuit for relay RIB from wire |00, through normally closed contact Rlib and contact RISa. Contact Rlb closes, completing a holding circuit from wire |00, through said contact and a resistance |01 to the shift solenoid SHS. At 335, contact C2 opens, deenergizing relays Rl, R2, R4, R5, and RIZ. Contacts R|2a close and contacts R|2b and R|2c open, but relay R|8 and solenoid SHS remain energized. The next character code sensed will cause the printer to print in the uppercase.

To shift back to lower case position, the standard letters shift signal 12345 is used. If the sensing pins sense this combination in the tape, the relays R|R5 are energized and, when contacts C2 close, a circuit is completed through wire |05, transferred contact R|c, contact R2d now closed, transferred contact Rte, contact R4f now closed, transferred contact R5f, coil of relay R|| to wire |0|, energizing said relay. Contact Rl la opens immediately, breaking the normal circuit through wire |04 before the contacts C3 close and thus preventing the code relays from being energized during this cycle. Contact R| |b opens, breaking the holding circuit of relay RIS. Contact Rlb opens, dropping out the case shift solenoid SHS. At 335 the contact C2 opens, deenergizing the relay RH and allowing the contact RI la to close, restoring the normal circuit through wire |04. The next character code sensed will cause the printer to print in the lower case.

It will be noted that the case shift signals operate in either code.

Carriage return mechanism The carriage return code is the number 4 hole. When this is sensed in the tape, the relay R4 is energized and, when contacts C2 close, a circuit is completed through wire |05, normal contacts R|c, R20, and R311, transferred contact R403, normally closed contact R5d, pick-up coil of relay R|5, to Wire |0|, energizing said relay. The contact R|5a closes, completing a circuit from wire |06 through normally closed contact R26c and the contact R|5a, through the holding coil of relay R|5. Contact R|5c opens, disabling the circuit of the latch magnet LM. The armature 30v remains in latching position at the end of the cycle and the tape reader is prevented from continuing to read the tape, though the motor RM and cam contacts CI-C5 continue to operate. The energization of relay R4 also prepares the circuit to the code magnet M4 so that, when contact C3 closes at 144, the normal circuit is completed through wire |04 to the code magnet M4, energizing said magnet. This causes the carriage return key CR of the printer to be operated.

Meanwhile, the contact Rld closed when the relay R|5 was energized. rThis prepared a circuit for a cycling sequence, to provide time for the carriage return, which will now be described. When contact C2 opens near the end of the cycle in which the carriage return key is operated, the relay R4- is deenergized and contacts R4d return to normal position. On the next cycle, when contact C2 closes, a circuit is completed through wire |05, normal contacts R|c, R20, R3d, and R441, wire |08, contact Rld (now closed), wire |09, normal contacts R23b and R241), coil of relay R22, to wire IOI, energizing said relay. Contact R22a closes, completing a holding circuit for relay R22, directly from the wire |08 and thence through the previously traced circuit including contact C2. Contact R221) closes, completing a circuit from wire I 09, through the pick-up coil of relay R23, to wire IOI, energizing said relay. Contact R23a closes, completing a holding circuit for relay R23 directly from wire |00, through Wire I I0, normal contact R240, contact R23a, the holding coil of relay R23, to wire IOI. Contact R231) transfers but without immediate effect, because contact R220 is open at this time.

Near the end of the cycle, contact C2 opens, breaking the holding circuit of relay R22, which `drops out, restoring contacts R220 to their normally closed position. When Contact C2 closes early in the next cycle, a circuit is completed from wire |09, through transferred contact R231), contact R220, now closed, the pick-up coil of relay R24, to wire I I, energizing said relay. Contact R2I|a closes, completing a secondary holding circuit for relay R23 through contact R231) to wire |09. Contact R240 transfers, completing a holding circuit for relay R24 direct from wire H0, through normally closed contact R261) and the holding coil of relay R24. The transfer of Contact R240 breaks the holding circuit of relay R23 to the wire |I0, but this relay remains energized through the above described secondary holding circuit. When contact C2 opens near the end of the cycle, relay R23 drops out, the relay R24 remaining energized.

When contacts C2 close early in the third cycle, a circuit is completed from wire |09, through normal contact R231), transferred contact R241), the coil of relay R26 to wire IOI, energizing said relay. Contact RZSa closes, completing a holding circuit for relay R20 from wire |08, through wire III. Contact R261) opens, breaking the holding circuit of relay R24, which drops out. Contact R200 opens, breaking the holding circuit of relay RI5, and which also drops out, restoring the contact RI5c to its normal closed position, so that the latching magnet LM will be reenergized when the cam contact C5 closes near the end of the third cycle. About this time, the contact C2 opens, deenergizing the relay R26 and restoring the cycling circuits to normal condition.

Lz'ne feed circuit In the type of printer disclosed carriage return and line feed are accomplished concurrently by operation of the carriage return key. If the carriage is in its fully returned position when the carriage return key is operated, a line feed alone takes place. The code employed includes the standard line feed signal 2, in addition to the standard carriage return signal 4, so that the messages can be monitored by machines requiring the line feed signal. The carriage return signal is always followed by a line feed signal, but a line feed signal may occur without a preceding carriage return signal, where plural line feed is required. It is necessary to prevent a line feed code from causing an operation of the carriage return key of the printer disclosed in this application, when the line feed code is preceded by a carriage return code; otherwise, there would be a double line feed where not intended. However, when a line feed code is not preceded by a carriage return code, it must operate the carriage return key. The means for accomplishin these functions will now be described.

When a carriage return code signal 4 is sensed vrelay R2I, to wire |0I, lContact R2Ia closes,

in the tape,'it causes the operations previously described, including the energization of relay RI 5. Contact RI51) closes, completing a circuit from wire |06, through said contact and pick-up coil of relay R20, to wire |0I, energizing said relay. Contact R20a closes a holding circuit from wire |06, through normally closed contact R2I1), to the holding coil of relay R20. Contact R201) transfers, disabling the circuit of code magnet M2.

When a line feed signal 2 is sensed, after the previously described delay of three cycles, the code relay R2 is energized and, when contact C2 closes, a circuit is' completed through Wire |05, normal contact RIc, transferred contact R20, normal contacts R30, R40, R50, pick-up coil of relay RIS, to wire IOI, energizing said relay. The` contact RIIa closes, completing a circuit from Wire |06, through normally closed contact R260 and the holding coil of relay RIG. Contact RIBd closes, preparing a circuit fora three cycle delaying sequence, as previously described. Contact RIIc opens, preventing the latch magnet from being energized at the end of the cycle, thus stopping the `reading of the tape.

When contact C3 closes at 144, the normal circuit is completed through wire |00, contact R21), transferred Contact R201), wire II 2, coil of energizing said relay. completing a holding circuit through holding coil of relay R20, holding said relay and thus continuing to disable the circuit of code magnet M2, until after the contact C3 opens at 250 in the rst cycle. Contact R2I1) opens, breaking the holding circuit of relay R20 to the wire |06. Thus, the number 2 code signal is diverted through the relay R2I, so as not to energize the code magnet M2, while a second delaying sequence is initiated to provide time for the carriage return and line feedoperation of the printer.

If a line feed signal occurs not preceded by av carriage return signal, the contact R201) will be in normal position when the cam contact C3 closes and the code magnet M2 will be energized. This code magnet causes an operation of the keyless lever '161) (Fig. 4) and thus of the carriage return key CR. A line feed signal not preceded by a carriage return signal occurs only when the carriage isY in its fully returned position. Operation of the carriage return key, therefore, causes only a line feed operation.

summarizing the operation of the carriage return and line feed circuits, the carriage return code causes an operation of the carriage return key in either zone and stops the tape reader for three cycles. The line feed code following the carriage return code delays the reader for three more cycles, but does not cause an operation of the carriage return key. Thus, the reader is delayed for six cycles while the carriage is returning.

After the carriage is returned, if an additional line feed signal appears in the tape, it causes an operation of the carriage return key and stops the reader for three cycles.

Tabulation- The TAB key on the typewriter is in Zone 2'. The tabulation code is 124. This is the same code as the letter y but the fact that tabulation is in zone 2 means that the relay RIS will be energized, preparing the circuit for code magnet M6. Accordingly, when the code 124 is sensed in the tape with the relay RIS energized, when the contact C2 is closed a circuit will be completed through wire |05, transfer contact RIc,

lating into a printed message combinational code signals in a code based on a small number of different code positions, a printer having a keyboard comprising a, larger numbe` of keys than the possible number of different combinations of the code, said keyboard being subdivided into zones each including a different group of keys, a permutation mechanism for controlling the selective operation of said keys comprising a zoning permutation member for selecting the zone and code permutation members corresponding to the respective code positions for selecting the keys Within a zone, electromagnetic devices for controlling said permutation members, energizing circuits Yfor said electromagnetic devices, signal responsive means controlling the circuits of the electromagnetic devices pertaining to said code permutation members, a supervisory relay controlling the circuit of the electromagnetic device pertaining to said zoning permutation member, zone shift relays controlling the energization and deenergization of said supervisory relay, energizing circuits for said zone shift relays including means controlled by said signal responsive means for selectively preparing the same, the energizing circuits for said electromagnetic devices including normally closed contacts adapted to be opened by either of said zone shift relays, the energizing circuits of said zone shift relays and of said electromagnetic devices including normally open timing contacts, and means for closing said timing contacts sequentially, rst those in the energizing circuits of said zone shift relays, then those in the energizing circuits of said electromagnetic devices.

10. In a printing telegraph apparatus for translating into a printed message signals recorded in a combinational code based on a small number of code positions, a printer having a, keyboard comprising a larger number of keys than the possible number of combinations of the code, said keyboard being subdivided into Zones each including a different group of keys, a permutation mechanism for controlling th'e selective operation of said keys comprising a zoning permuta- 14 tion member for selecting the zone and code permutation members corresponding to the respective code positions for selecting the keys within a zone, electromagnetic devices for controlling said permutation members, energizing circuits for said electromagnetic devices, a cyclically operable record reading device comprising code contacts operated in accordance with the code designations of the record, code relays having individual circuits controlled by the respective code contacts,

zone shift relays, circuits for said zone shift relays including contacts controlled by said code relays so as to prepare said circuits selectively on response of said code relays to certain zone shift signal combinations, a supervisory relay controlled by said zone shift relays, a normal circuit comprising branches for the electromagnetic devices pertaining to said code permutation members including contacts operated by said code relays and a branch for 'the electromagnetic device pertaining to said zoning permutation member including a contact operated by said supervisory relay, said normal circuit including normally closed contacts operated by said zone shift relays and timing contacts closed by said record reader at a certain time in the cycle, the circuits of said zone shift relays including timing contacts closed by said record reader at an earlier time in the cycle than said rst mentioned timing contacts.

1l. In a page printer for printing messages in response to combinational code signals, a carriage return key lever, a line feed lever adapted to operate said carriage return key lever, permutation mechanism, means controlled by said permutation mechanism for selectively operating said levers, control means responsive to a line feed signal combination for causing said permutation mechanism to select said line feed lever, and control means responsive to a carriage return signal for -causing said permutation mechanism to select said carriage return lever and for suppressing the operation of said rst mentioned control means during th'e following signal period.

CLYDE J. FITCH.

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