US2082511A - Printing telegraph apparatus - Google Patents

Printing telegraph apparatus Download PDF

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US2082511A
US2082511A US742067A US74206734A US2082511A US 2082511 A US2082511 A US 2082511A US 742067 A US742067 A US 742067A US 74206734 A US74206734 A US 74206734A US 2082511 A US2082511 A US 2082511A
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lever
latch
selector
arm
selecting
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US742067A
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Albert H Reiber
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AT&T Teletype Corp
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Teletype Corp
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L17/00Apparatus or local circuits for transmitting or receiving codes wherein each character is represented by the same number of equal-length code elements, e.g. Baudot code
    • H04L17/16Apparatus or circuits at the receiving end
    • H04L17/18Code selection mechanisms

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transmission Devices (AREA)

Description

June1,1937. A.H.REIBER 2,082,511
PRINTING TELEGRAPH APPARATUS I Filed Aug. 50, 1954 lNVENTOR 49 2 4455/97 H. 05/552 66 65 23 5% v 2 ATTORN v Patented June 1, 1937 UNITED STATES PRINTING TELEGRAPH APPARATUS Albert H. Reiber, Evanston, Ill., assignor to Teletype Corporation, Chicago, 111., a corporation of Delaware Application August 30,
26 Claims.
The present invention relates to printing telegraph apparatus and more particularly to improvements in mechanical selecting mechanisms therefor.
Start-stop systems of telegraphic signalling have each group of code signals preceded by a start or spacing condition and followed by a stop or marking condition.
It is apparent, that in selective devices em ployed in such systems there is possible a continuous uncontrolled rotation of the selector elements when the signal line is allowed to remain indefinitely in the starting condition. This condition is prevalent in some telegraph switching systems while connections are being set up, as in a printing telegraph exchange system, or when the line is left open negligently or for any other reason. When a receiver is thus allowed to rotate uncontrolled and is then stopped by a marking impulse, a false signal results unless the marking impulse thus transmitted coincides with the pro-per position of the receiver for so securing a stop impulse. The probability of such a coincidence is remote so that this susceptibility to 5 false signals may be said to be general.
It is accordingly a principal object of this invention to provide a selecting mechanism which has special means to prevent false operation of the receiver under certain conditions.
The above and other objects of the invention are accomplished by the provision of a single magnet selector mechanism responsive to code combinations of signalling impulses, for example, of the type disclosed in U. S. Patent No. 1,745,633 to S. Morton et a1. wherein the selector cam member constantly tends to rotate, but which is normally restrained therefrom'by a latch means which is controlled by the armature of the selecting magnet. This latch means is operated to release the cam member for rotation upon receipt of a signalling impulse, known as a start impulse and which is of a predetermined polarity. Since an open line condition is equivalent to a start condition, it is manifest that the former l5 condition will also result in the release of the latch means and hence, if such open line condition persists, the selector cam member will rotate continuously. To obviate this latter occurrence, the present invention provides an auxiliary means comprising a spring actuated latch, which cooperates with the first mentioned latch to prevent the continuous rotation of the selector cam member due toan open line condition. Specifically, the auxiliary latch is arranged to be effective for arresting the rotation of the selec- 1934, Serial No. 742,067
tor cam member under selective conditions opposite tothat obtaining to render the normal latch similarly effective.
A better understanding of the invention may be had from the following description, taken in conjunction with the accompanying drawing wherein,
Fig. 1 is a fragmentary plan view of a selector mechanism of the sword-and-T-type, controlled by a neutral magnet, with portions omitted or broken away to reveal the essential operating members in which the present invention is embodied;
Fig. 2 is a sectional view taken substantially on line 2-2 of Fig. 1, and shows the anti-spin device under normal operating conditions of closed circuit, and
Fig. 3 is a sectional view similar to Fig. 2 with the anti-spin device shown in open circuit operating position.
Having reference to the accompanying drawing in which like reference characters indicate similar parts throughout, the selector mechanism illustrated in Fig. 1 is similar to that which is used commercially in several standard types of printing telegraph machines. The details of the selector mechanism disclosed are shown only in sufficient detail to enable an understanding of the present invention. For a complete understanding of details not disclosed herein and which form no part of the present invention, reference may be hadto the aforementioned Patent No. 1,745,633.
The mechanism comprises a set of six (or five,
depending on the code adopted) selector elements a in the form of thin, flat fingers or swords II arranged in superposed relation between guide plates I2. These plates are mounted on studs I3 and spaced by washers not shown. The circular rear ends I4 of the fingers I I engage corresponding sockets I5 in six thin, flat bell cranks I6, pivoted on a common shaft I 1. Individual springs I8 normally hold the bell cranks I6 and selector fingers I I in the position shown in Fig. 1 with the heel or end I9 of the bell crank I 6 in contact with a selector cam barrel 2| on shaft 22 (Fig. 2) which is driven continuously by a properly regulated motor, the driving connection between the shaft 22 and the cam barrel 2| being established through friction clutches 23 and 24 (Fig. 2).
The cam barrel 2I is provided with a helically arranged series of cams 25, one for each of the bell cranks I6, which rotate the bell cranks I6 (six in the presentinstance) in succession and thus reciprocate longitudinally the corresponding series of selector fingers or swords II as the cam barrel 2| is rotated. In addition to the longitudinal movement, the selector fingers II have a lateral swinging movement between the pair of studs 26 (Fig. 1).
The setting of any selector finger either to its dotted-line or its solid-line position (as indicated in Fig. 1) is determined by the selector electromagnet' 21' which is mounted on a bracket 28 in the printing apparatus. The armature 29 is carried by a selector lever 3| which is pivoted on a shaft 32 supported in the frame of the apparatus. The unit comprising lever 3.l and armature 29 constantly tends to rotate in a clockwise direction, due to: the tension of a spring 38, but is restrainedfrom such movement when magnet 21 is energized. Thus, during a marking or closed line condition, the selector lever 3| will be held in the position shown in solid. lines in Fig. 1, but upon an open line conditio-n, magnet 21 will be deenergized. and lever 3| will assume the dotted line. position due to. the action of spring 38', the tension of which may be adjusted by an adjusting screw 39. Lever 3| terminates in a U-shaped portion 35, having downward extending. arms 35' which constitute abutments which cooperate with arms 31 on the rear ends of the swords or selector fingers II, and act to position thelatter in either the dotted.- line or solid-line position. That is, the distance between the depending portions 38 of lever 3| is somewhat less than the distance. between each cooperating pair of lugs 31, so that when. either of the portions 3.6 is disposed to register opposite its cooperating, lugv 31-, the other of the two. portions 36 falls short of engagement with. its co operating lug 3T. As seen from Fig- 1,.spring. 38 tends to maintain lever 3| in a. position so. that one of its portions 36 registers opposite its associated lug 31, while magnet 21, upon energization, operates to maintain it so. that the other of its depending portions 38 registers opposite its associated lug 31. In. other words, the energize.- tion of winding 21 causes the presentment. of lever 3| in one position to cooperate with one of the abutments of the selector fingers while its deenergization causes. its presentment. in. the. other position to cooperate with the other of the pair of lugs 31.
The selector fingers act. through. a corresponding number of T-shaped levers 4| arranged between the guide plates l2 and. pivotally mounted on a shaft 42', to position a set. of code elements which. are not. shown but. are exemplified by the fragment. .43 and are capable of being moved into one or the other of two positions. To each element 43 is articulated one arm of. T-lever 4|. As indicated, T-lfevers 4| are provided with two symmetrical or oppositely. disposed extensions which coact with the end. of. their individual selector fingers so that. the T-lever 4| is rocked in conformance with the.
selected position of selector finger H to actuate in turn its associated element 43 correspondingly..
Referring further to Fig. I, it is noted. that the selector lever 3| is. provided with a projection 44 terminating in an eccentric adjustment screw 45, the function of which is to initiate, through. a series of levers, the rotation of the selector cam barrel 2| in the following manner.
Having reference. to Fig. 2, it is observed. that the adjusting screw 45 carried by the selector lever 3| cooperates with a plunger 45 'slidably carried in the support 41 of the orientation member, indicated'generally as 48, to actuate a trip member in the form of a small bell crank 49 pivotally mounted in bracket 41 so that its inner arm may engage one arm of a latch 5| pivoted at 52 in a support 53 also carried by the orientation member 48. The extremity of the horizontal arm of the bell crank 48 engages the latch 5| at a point coincident with the coaxial alignment of shaft 22 and a pivot stud 54, the purpose of which will hereinafter appear. Arm 55 of latch 5| is provided with a shoulder which coacts with arm 56 of a U-shaped stop gate 51 rotatably mounted on a pivot stud 58. The latch arm 55 is-normal-ly held in cooperative engagement with arm 56 of' the stop gate 51 by a compression spring. 55.. Arm. 5| of stop gate 51 is adapted to be engaged by an upstanding arm 62 of the stop disc- 65 fixedly related to the cam barrel 2| so as to rotate therewith.
Also associated with the arm 56 of the stop gate- 51 is: a safety or anti-spin latch member 64 which is pivoted at 65 to a support 66 carried by the orientation member 48. Latch 64 constantly tends to rotate in a counterclockwise direction by means of a spring 61, thus urging the right-hand end of the latch 64 (as viewed in Fig. 2) against arm 56 of the stop gate 51. This end of the latch 64 just referred to is also provided with a shoulder which, under certain conditions, engages-arm 55 of stop gate 51. At-
tention is directed to the fact that shoulder 68 of latch 5| is not in direct vertical alignment with the shoulder 59 on. latch 64, but the latter is disposed slightly to the left (as viewed in Fig. 2) of shoulder 68, the purpose of which is to insure the effectual. andv invariable operation of the anti-spin device. In this manner, latch 54 forms with latch 5| a double trip-off latch. Latch 5| is also provided at its left extremity with a depending portion 11 which acts, when shoulder 58 engages arm 55, to maintain shoulder 69 of latch 64 out of cooperative relation with arm 56'. It is noted. that when latch 5|. is free. to rotate in a counterclockwise direction under action of. spring 59 due to the inaction thereupon by bell crank 49 during a. marking condition, spring 59. overpowers spring 51 and thus latch5| is normally engaged with arm 56...
As clearly set forth in the aforementioned patent, the latch.5|, stop gate 51, and their respective. pivots. are mounted on an adjusting plate 12 of the orientation device 48. The adjusting plate may be rotated about the pivot 54 by means of an arm 73 having an operating. knob 14 and may be clamped, by any well-known means, to the calibrated plate of the orientation device 48.
The. condition of the unlatching means shown in Fig. 2 is that which obtains when the selector mechanism assumes the position shown in Fig. 1 during. a. marking condition of the line. In this position, having referencev to Fig. 2, the adjusting screw 45 and plunger 45v assume their rightward position and bell crank 49. its clockwise position. In this position, latch. 5| is free to respond to the action of spring 59 into interlocking engagement witharm 56 0f stop gate 51 tobring arm 6| in position to arrest the stop disc 63 and hence cam barrel 2|. Cam barrel 2| and. stop disc 83: constantly tend to rotate due to their frictional connection with constantly rotating shaft 22. Thus, asviewed in Fig. 1, stop disc 63, through its arm 52, tends to rotate stop gate 51 in a counterclockwise direction against action of spring 15, but this. movement is resisted by the shoulder 68 on latch 5|; However, upon the receipt of a start or spacing signal which is equivalent to an open.
line condition, the magnet 21 is deenergized and the selector arm 3| is rotated clockwise (Fig. 1) under the action of its spring 38. This causes the adjusting screw 45 to be actuated leftwardly, as viewed in Fig. 3, to actuate plunger 46 correspondingly, thus imparting counterclockwise movement to bell crank 49. This movement of bell crank 49 causes latch to rotate in a clockwise direction against the action of its spring 59 sufiiciently to withdraw shoulder 68 from cooperative engagement with arm 56. However, due to the fact that shoulders 68 and 69 are not in vertical alignment, the shoulder 69 cannot act at this time to restrain movement of the stop gate 51 because, as viewed in Fig. 2, during the normal stop condition of the line the shoulder 69 is out of cooperative engagement with arm 56, hence stop gate 5! is free to respond to the greater pressure imparted to it by stop arm 62 which overcomes spring 75. Stop gate 51 thus rotates with 62 until arm 6| has become disengaged from arm 62, whereupon arm 62 and hence cam drum 2| continue to rotate during the ensuing cyclic period, and stop gate 51 is returned to its clockwise position (as viewed in Fig. 1) by spring 15. However, there is a slight overtravel of the stop gate 51 in this return movement, so that arm 56 will be moved leftwardly, as viewed in Figs. 2 and 3, suificiently to permit the engagement of shoulder 69 and arm 56, as indicated in Fig. 3. The condition shown in Fig. 3 obtains during a continued open condition of the line or whenever spacing impulses are received and prevents the cam drum from spinning during the existence of such a condition. Such an open line condition would, if permitted, cause the printing of false characters.
Now, when the line is again closed and selector magnet 21 again energized, armature 29 will be attracted and selector lever 3| will be rotated counterclockwise to actuate adjusting screw 45 rightwardly, as viewed in Fig. 3, whereupon latch 5|, under the action of spring 59, will tend to assume the position shown in Fig. 2. In effecting this result, portion H of latch 5| will force the rightward arm of latch 64 downwardly against the Weaker pressure of spring 61, thereby causing shoulder 69 to slide off of arm 56 which, due to the offset or stepped relation between shoulders 68 and 69 will become engaged by shoulder 68 and be thereby retained during a closed or stop condition of the line circuit, it being remembered that stop gate 51, during this operation, is constantly having pressure exerted upon it by arm 62 associated with cam drum 2| which, as previously mentioned, constantly tends to rotate.
It is, of course, understood that this invention is capable of embodiment in other forms than that specifically disclosed without departing from the spirit and scope of the invention as defined in the appended claims.
What is claimed is: a
. 1. In a printing telegraph selector system, means responsive to code combinations of selecting conditions, rotary selecting elements controlled by said means, and a double trip-off latch mechanism efiective under certain conditions for arresting said selecting elements.
2. In a start-stop telegraphic selector responsive to received code combinations of two selecting conditions, arresting means controlled by one of said conditions, and other arresting means controlled by the other of said conditions, said other arresting means arranged in stepped relation with said first arresting means to insure the arrestment of operation upon a prolongation of said other condition.
.3. In a printing telegraph selector system, means responsive to code combinations of selecting conditions, rotary selecting elements controlled by said means, a stop gate effective under certain conditions to arrest said rotary means, and a pair of latches adapted to be severally coactive with said stop gate to efiect, through said stop gate, invariably a single cycle of operation of said rotary means.
4. In a printing telegraph selector system, means responsive to code combinations of selecting conditions, rotary selecting elements controlled by said means, release means comprising a spring-biased bell crank lever, and a pair of latches also responsive to said first. means for controlling the release of said rotary selecting elements, said pair of latches adapted to be severally coactive with said bell crank lever to effect invariably a single cycle of operation of said rotary selecting elements.
5. In a printing telegraph selecting system, means responsive to code combinations of selecting conditions, rotary selecting elements controlled by said means, means controlled by said. rotary selecting elements to initiate the operation of said means including a pair of pivoted members arranged with oppositely disposed irregular surfaces, and a latch element positioned between said members and cooperating with the irregular surfaces thereof operable initially in response to one line condition to hold said rotary elements inefiective and operable subsequently if said line condition is changed to continue to hold said rotary elements inefiective.
6. In a printing telegraph selecting system, means responsive to code combinations of selecting conditions, a rotary selecting device controlled by said means, means including a first component and a second component controlled by said second recited means to initiate the operation of said rotary selecting device, latch means normally coactive with said first component and non-coactive with said second component; and means to render said latch means coactive with either component to determine the cyclic operation of said device.
'7. In a printing telegraph selecting system, means responsive to code combinations of selecting conditions, a rotary selecting device controlled by said means, means including a first component and a second component controlled by said means to initiate the operation of said mechanism, latch means normally coactive with said first component and adapted normally to escape said second component, and means to render said latch means cooperative with either component to determine the cyclic operation of said mechanism.
8. In a printing telegraph selecting system, means responsive to code combinations of selecting conditions, a rotary selecting device controlled by said means, means controlled by said means to initiate the operation of said device, said second recited means including a pair of pivoted members arranged with oppositely disposed stepped surfaces, means adapted normally to bias said members into contactual engagement whereby said surfaces are presented in offset relation to each other, a latch element positioned between to determine. the cyclic operation ofsaid device.
9. In a start-stop telegraphic selector, means responsive to: received code combinations of two selecting: conditions, a rotary selecting device controlled. by said means, arrestingmeans for said. device comprising a first component and a secondv component, and: latch. means normally coactive. with: said first: component in response to one: of. said selecting conditions. and adapted to escape said second component, said second component efiective in response to the other of said selecting conditions to insure the limitation of: rotation. of. said device to a single cycle.
10. A rotary selector mechanism including a start-stop. rotor, starting means responsive to-a uniform signalling condition at the-beginning of asignal, and? stopping means comprising a double. trip-on latch responsive to a plurality of different signalling conditions at the close of a signal.
11. In combination, aconstantly rotating member, a member to be driven by said constantly rotating member, a frictional connection between the two members, means comprising a plurality of pivotally mounted members for locking the second recited member against rotation, and further means acting independently upon the ineffectiveness of said means for locking said second recited member against rotation.
12'. In combination in a selector mechanism responsive to signal line conditions, a constantly rotating member, a member to be driven by said constantly rotating member, a frictional connection between the two members, means comprising a plurality of pivotally mounted members effective during a closed line condition and ineffectime during an open line condition for locking the second recited member against rotation, and further means ineflective during a closed line condition and effective during an open line condition for locking said second recited means against rotation.
13. In combination, a constantly rotating member, a member to be driven by said. constantly rotating member, a frictional connection between the two members, an anti-spin device comprising a pai'rof pivotally mounted members, and. means for biasing said pivotally mounted members at trahently for locking. said second recited member against unlimited rotation irrespective of the operative position of said device.
141,111 a printing telegraph selector system, means responsive to code combinations of select ing conditions, rotary selecting elements con trolled by said means, and a double trip-off latch mechanism for lockingsaid rotary selecting elements against rotation in response to predetermined conditions.
15. In combination, a rotatable member, a locking lever adapted to engage the rotatable member for preventing rotation thereof, a second lever adapted to engage the first lever for locking the same, means for controlling the second lever under certain conditions, and means efiective in substitution of said second lever in response to theinefiectiveness of said first recited means for locking said first lever.
16. A locking means comprising a lever, one end of which is adapted to engage a member to be looked, a second lever, one end of the second lever being adapted to engage the other end of the first lever, means for controlling the second lever, and means also effective on said other end aosagzn 1 upon the. ineffectivenessof said second lever to lock. sai'dfirst lever.
17.. A locking meanscomprising a locking lever, one end: of which is adapted to engage a member to be-locked, a first means cooperating with the 5 other end 01 said locking lever for preventing rotation: thereof, and a second means cooperating with said first means to prevent under certain predetermined conditions the rotation of said locking lever.
18. In combination with a member to be looked, a locking lever having one end adapted to engage said member, said member tending to rock said locking lever, asecond lever for locking the first lever against rocking movement, and a third lever effective, upon the ineifectiveness of said second lever, to: lock said first lever against melting movement.
19. In combination, a rotatable member, a locking 'lever' adapted to engage the rotatable member for preventing rotation thereof, a second' lever adapted to engage the first lever for locking the same, means for controlling the second lever under certain conditions, means operative in substitution of said second lever to locksaid first lever, and unbalanced spring means to render said second recited means effective upon the ineffectiveness of said first recited means.
' 210 In combination with a member to be'locked', a lockinglever'having one end adapted to engage said member, said member tending to rock said locking lever, a second lever for locking the first lever against rocking movement, a third lever cooperable with said second lever for looking said locking lever against rocking movement, and unbalanced spring means to render said third lever effective upon the i'nefi'ectiveness of said second lever.
' 21". Incombination, aconstantlyrotatingmemher, a member to be driven by said constantly rotating member, a frictionalconnection between the two members, ananti-spin device comprising a plurality of" pivotally mounted members, a first spring means to" cause certain of said pivotally mountedfimembers to become effective initially to prevent the continuous rotation of' said second recitedmember, and a second spring means to cause the other of said pivotally mounted members to become effective independently to prevent more than a single cyclic rotation of said second recited member;
. 22. In combination, a constantly rotating member, a member to be driven by said constantly rotating member, a frictional connection between the two members, an anti-spin device comprising a plurality of pivotally mounted members, and means acting independently upon the. ineffectiveness of said pivotally mounted members to prevent more than a single cyclic rotation of said second recited member.
23.. A locking means comprising a locking element, one portion. of which is adapted toengagea member to be locked; a first spring actuated means cooperating with another portion of said locking element for preventing rotation thereof, and a second spring actuated means acting independently upon the inefiectiveness of said first means to prevent under certain predetermined conditions the rotation of said locking element.
' 24.. In: combination, a constantly rotating member; a member to be driven by said constant- 1 rotating: member, africtional connection between. the two: members, and an anti-spin device comprising a first means to prevent the continuous rotation of said driven member and a second means effective independently upon the inefi'ectiveness of said first means to prevent more than a single cyclic rotation of said driven member.
25. In combination, a constantly rotating member, a member to be driven by said constantly rotating member, a frictional connection between the two members, and an anti-spin device comprising a plurality of pivotally mounted members, certain of said pivotally mounted members effective to prevent the continuous rotation of said second recited member and the other of said pivotally mounted members efiective independently in response to the ineffectiveness of said certain of said pivotally mounted members to prevent more than a single cyclic rotation of said second recited member.
26. In combination, a constantly rotating member, a member to be driven by said constantly rotating member, a frictional connection between the two members, and an anti-spin device oomprising a first means to prevent the continuous rotation of said second recited member and a second means efiective independently in response to the inefiectiveness of said first means to prevent more than a single cyclic rotation of said second recited member.
ALBERT H. REIBER.
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