US2170316A - Printing telegraph apparatus - Google Patents

Description

g- 22, 1939 w. J. ZENNER 2,170,316

PRINTING TELEGRAPH APPARATUS Filed Dec. 31, 1956 iNVENTOR WALTER J. ZENNER ATTQRNEY Patented Aug. 22, 1939 UNITED STATES PATENT OFFICE PRINTING TELEGRAPH APPARATUS tion of Delaware Application December 31, 1936, Serial No. 118,526

12 Claims,

This invention relates to printing telegraph apparatus, and particularly to a selector mechanism for the control of such apparatus.

An object of the invention is to provide a selfaligning mounting for the armature of a selector magnet.

A further object of the invention is to provide flexible spring pivot mountings for levers in a selector mechanism.

Briefly, the invention contemplates, in one of its phases, the use of flexible hinge mountings comprising flat springs for supporting the armature lever and selector lever, so that instead of such levers being rockably mounted upon pivot screws or other bearing members, they rock or rotate through the necessary angles by the flexing of the flat spring members.

In the phase of the invention which pertains to the selector magnet, a rockably mounted armature lever carries the selector magnet armature in spaced and yieldable relation to said lever, so that the armature may rock about its mounting and come into engagement with the pole faces of the magnet without requiring that critical adjustment of the armature lever that is essential to a rigidly mounted'armature.

For a full and complete understanding of the invention, and of the manner in which it may be practiced, reference may be had to the following detailed description, taken in connection with the accompanying drawing, in which Fig. 1 is a top plan view partly broken away, showing a selector mechanism embodying the several features of the invention;

Fig. 2 is an elevational View of the selector mechanism shown in Fig. 1;

Fig. 3 is a sectional view, taken on the line 3-'3 of Fig 1; and

Fig. 4 is a detailed perspective view, partly exploded, showing the salient'features of the selector mechanism of Fig. 1.

Referring now to the drawing, in which corresponding reference characters represent identical parts throughout the several views, and particularly to Figs. 1 and 2, reference numeral l0 designates a mounting plate which serves as the foundation of the selector mechanism. Adjacent to one end, mounting plate !0 has secured thereto, by means of clamping screws II, a selector magnet assembly indicated generally by the reference numeral I2.

Selector magnet assembly !2 includes a bracket !3 through clearance holes in which pass the clamping screws ll. Bracket l3 is movable 55 through an arc, for purposes of adjustment, about an integral cylindrical projection !4 which is disposed in a similarly shaped and correspondingly dimensioned aperture in plate Ill, and pivotal movement is eflected by rotation of a screw !6, the shank of which threadedly engages 5 bracket !3 at the opposite end to that which carries pivot projection !4.

Screw i6 is provided with slotted head H, and in spaced relation to head I! with flange 8. Plate ll] has fixed thereto and extending upwardly therefrom stud IS, the upper end of which terminates between screw head I! and flange !8. Stud !9 being thus confined between screw head I! and flange l8, screw !6 is incapable of axial movement, and when it is rotated, bracket !3 is moved angularly about the axis of projection !4. Screw head I! is provided with radially extending sockets 2! in the periphery thereof, so that when the selector mechanism is installed in such position that access to the slot by screw driver cannot be had, screw !6 may be rotated by a bar-shaped implement applied to successive ones of the sockets 2|, in the manner in which capstans are rotated.

Bracket !3 has magnet core 22 secured thereto by means of screws 23. Core 22 has two arms, each of which supports an electrical winding 24 and terminates in a pole face 26.

An armature lever assembly 3! comprises a bell crank lever having arms 32 and 33. Arms 32 and 33 may be integral, and adjacent to the point of intersection of these arms is secured, by means of clamping block 34 and screws or rivets 36, a thin, flat strip of flexible material, such as spring steel, which is intended to serve as a mounting hinge for the armature lever, and is identified by the reference numeral 31. Spring hinge 3'! extends free of armature lever arm 32 and clamping block 34, and the free portion is rigidly secured to bracket !3 by means of clamping block 38 and clamping screws 39. Preferably, arm 32 of armature lever 3! overlaps bracket !3 slightly at the point of clamping of spring hinge 3'! in order that endwise movement of arm 33 of the armature lever, due to flexing of spring 45 hinge 31, may be prevented. Fig. 4 aifords an enlarged detailed view of the mounting of the armature lever on its spring hinge.

At its free end, armature lever arm 32 supports a floatingly mounted selector magnet armature 4! 50 in a manner clearly indicated in Fig. 4. Referring to that figure, it will be noted that armature lever arm 32 is provided with an aperture 42 which is adapted to receive the shank of a headed screw 43. Preferably, aperture 42 is of such diameter, by comparison with the shank of screw 43, as to be a clearance hole therefor, so that the shank of screw 43 may be capable of shifting about within aperture 42. Lever arm 32 has anchoring pins 44 positioned on opposite sides of aperture 42 extending above the surface of lever arm 32 which is presented toward the pole face 26 of the selector magnet. A flexible spring member 56 has apertures 41 adapted to fit over pins 64, and a central aperture 38 adapted to be entered by screw 43. Spring member M has arms 49 extending clear of armature lever arm 32 in opposite directions and arms 49 are preferably bent toward pole faces 25. Armature member ll has: a threaded aperture 5! which is threadedly engaged by screw 43, and also has grooves 52 in which the outer ends of arms 49 of spring member it are seated. Armature l! is thus supported on armature lever arm 32 by screw 43 and is maintained in spaced relation to the armature lever armfby spring member 45. A spacer 59 limits movement of armature AI in the direction of the axis of screw 43. Pins 34 prevent spring member 46 from. rotating on screw 43, and grooves 52 confine armature II to an upright position. The armature is free to rock in order to align. itself with the pole faces 26 when the armature is presented to the pole faces, and a critical alignment of armature lever arm 32, with respect to pole faces 26, is not required.

Arm 33 of the armature lever includes cam follower portion 56 arranged to engage an armature cam 5'! included in cam assembly 58 carried by a power-driven shaft 59. At its outer end, lever arm 33 is engaged by one end of a tension spring BI, the other end of which engages a bracket arm 62 adjustably mounted by means of split mounting block 63 and clamping screw fi l to post 66 carried by mounting plate HI. Arm 33 of the armature lever has secured thereto a bracket 6'! which has depending arms 68 and 59 positioned on opposite sides of lever arm 33 to serve as spring supports in a manner which will be described hereinafter.

In order that the previously mentioned cam assembly '58 may be disposed in a position topresent the several cams included therein in operative alignment with levers they are arranged to control, mounting plate IE is provided with'ap'erture II through which shaft 59, which may be driven from any suitable source, such as an electric motor, may project. Shaft 59 has secured thereto spaced discs I2. Between discs. I2, cam assembly 58 is mounted on shaft 59 and has at its opposite ends discs 13 fixedto the cam assembly. A' friction disc I4, of any suitable resilient material such as felt, is mounted on shaft 59 between each of the discs I2 and the adjacent disc I3. The assembly comprising discs I2, I3, and M constitutes a friction clutch through the medium of which rotation may be imparted to cam assembly 58 by shaft 59. In addition to armature cam 51, cam assembly 58 includes a locking cam I6 having a plurality of apices, and a plurality of cam projections I? arranged helically around the assembly. The functions of cam I6 and cam projections will be set forth hereinafter.

A selector lever assembly 8i includes a mounting bracket 82 adjustably secured to mounting plate II] in 'a manner fully described in copending application of E. W. F. Hanke, Serial No. 116,271, filed December 17, 1936. It may be stated, however, with reference to the mounting of bracket 82, that screws 83 are clamping screws extending through clearance holes in bracket 82, and screws B4 and 86 have eccentric heads provided for the purpose of adjusting bracket 82. Selector lever B! is rockably mounted upon bracket 82 by means of a spring hinge 88 similar to spring hinge 31. Spring hinge 88 is clamped to bracket 82 by means of clamping block 89 and clamping screws SI, and to selector lever 81 by means of clamping block 82 and clamping screws 93. Selector lever 81 may have cooperating therewith detent arm 94 pivotally supported at 96 in the manner fully described in. the above identified copending application of E. W. F. Hanke. Selector lever 81 may also have at its free end locking lug 91 which is adapted to be blocked under certain conditions by locking blade 98 of locking bell crank lever 99. This bell crank has one arm engaging cam 16 and is adapted to be rocked clockwise each time one of the apices of the cam. is presented to the bell crank.

Selector lever 87, is provided with depending arms IfiI and I02, which, as shown in detail in Figs. 3 and 4, cooperate with depending arms 58 and 69 of bracket 61 secured to armature lever arm 33 to support centering springs, by means of which selector leverB'I is caused to follow the selective conditions established in the armature lever. Thus, tension. spring I03 extends between arms 68 and H32, and tension spring I64 extends between arms 59 and NH. The tension of springs I I33 and I'M is such that selector lever 81 tends to be positioned. midway between arms. 68 and 69 of armature lever arm 33.

Selector lever 81 is provided at its free end with spaced depending arms I06 which are effective to control the several elements of a sword and T- lever selector mechanism designated generally by the reference numeral IIII. Sword and T-lever selector I01 comprise a' plurality of thin, fiat selector fingers or sword levers III and an equal number of T-levers H2 individually aligned with the selector fingers III. The selector fingers III are individually supported by spacer plates H3 which also separate the T-levers H2 and which are mounted on studs H4 carried by mounting plate III. Each of the selector fingers III has at its left-hand end, as viewed in Fig. 1, a disclike portion I I6 which is fitted into a correspondingly shaped aperture in a selector finger operating bell crank lever III pivotally mounted on a pivot pin H8. Each of the bell crank levers II! is arranged to be rocked counterclockwise by one of the cam projections 'I! included in selector cam assembly 58. Adjacent to the disc-like portion H6, each selector finger or sword lever III is provided with oppositely extending arms [I9 which terminate in abutments I2 I. I

T-levers H2 are rotatably mounted upon pivot pin I22 carried by mounting plate II], and each of the levers is provided with an arm I23. Arm I23 terminates in disc-like portionIZG. T-levers II 2 are intended to be articulated by means of the disc-like portions I24 to code bars, code discs, or other permutation code elements (not shown), as disclosed in Patent No. 1,745,633, granted February 4, 1930 to S. Morton et al. Selector lever 81 is adapted to be rocked in a manner which will be described later through an arc sufficient to bring one or the other of its arms I06 into the path of one or the other of abutments I2I of selector fingers III, as those fingers are reciprocated leftwardly by the associated bell crank levers I I1, and such angular movement of selector lever 81 is sufiicient to bring locking lug 9! from one side to the other of locking blade 98 carried by locking bellcrank 99. Continued reciprocation of a selector finger III after one of its abutments I2I has engaged one of the depending arms I06 of selector lever 81 causes the selector finger to move angularly about the center of its disc-like portion I IE to bring its free end into engagement with its associated T-lever H2 at the opposite side of the pivotal mounting I22 thereof. The angular movement of selector fingers III is limited by stop pins I26 carried by mounting plate II].

The rotation of selector cam assembly 58 by shaft 59 is controlled by a stop gate I3I which is periodically presented in blocking condition in the path of a stop arm I32 rigidly secured to selector cam assembly 58. Stop gate I3I is pivotally supported by stud I33 carried by plate I34 which is pivoted by means of pivot screw I36 to plate I37 rigidly secured on posts 68. An arm I38 mounted on pivot screw I36 above plate I3? has extending therethrough the shank of a knurled-headed screw I39 which threadedly engages stop gate mounting plate I34. Plate I34 may be adjusted pivotally about pivot screw I35 to vary the location of stop gate I3! and may be clamped in any desired position of adjustment by drawing plate I34 and arm I38 into clamping engagement with plate I31 by means of screw I39.

Stop gate I3I has an arm I4I which is presented in the path of cam assembly stop arm I32 when the stop gate is in its extreme clockwise position, and a spring (not shown) biases stop gate I3! so that it tends to rotate into its extreme clockwise position. The stop gate may be locked in the position to which it tends to be rotated by the engagement of a shouldered portion of latch lever I42 with arm I43 of the stop gate. Lever I42 is mounted on stop gate mounting plate 534 by means of pivot I44 and is normally urged into locking engagement with arm I43 of stop gate I4! by compression spring I46. A bell crank I4! pivotally mounted on bracket I48 carried by plate I31 has one arm I49 engaging stop gate locking lever I42 at the end opposite to the shouldered portion which engages stop gate I33, and has another arm I5I, the free end of which is disposed in a notch in the free end of armature lever 3I.

In the rest condition of a selector mechanism such as the one shown herein, when the mechanism is prepared to respond to incoming telegraph signals, but signals are not on the telegraph line, a continuous energizing current is applied to winding 24 of selector magnet I2, which causes its armature 4! to be attracted to its pole face 26. Since armature II is yieldingly mounted on arm 32 of armature lever 3|, it is not essential that arm 32 be adjusted. into exact parallelism with pole faces 26, because the armature is free to rock about its one-point mounting and engage both pole faces, even if armature lever arm 32 should happen to be twisted or bowed. As long as armature M is held attracted by the selector mag-net I2, the armature lever is held in its extreme counterclockwise position (as view in Fig. 1). In this condition of the selector mechanism, bell crank I4] and latching lever I42 are held in their extreme counterclockwise and clockwise positions respectively (as: viewed in Fig. 3), and stop gate iSI is locked in the position in which its arm I4I is disposed in the path of and blocks stop arm I32 carried by selector cam assembly 53. The cam assembly is thus held stationary despite the torque applied to it by continuously rotating shaft 59 through discs 12, I3, and T4. In the rest position of cam assembly 58,

a low portion of armature cam 51 is presented toward follower 55, which is out of engagement with cam 51 as a result of presentation of armature lever 3I in its counterclockwise position.

Printing telegraph mechanisms of the type for which the selector mechanism herein described is especially adapted are customarily operated on permutation code combinations of marking and spacing impulses, the former represented by energization of the selector magnet and the latter represented by deenergized condition of the magnet. Each permutation cocie combination of im pulses is preceded by a start impulse which partakes of the nature of a spacing impulse, Whereby the selector magnet becomes deenergized. When the start impulse is received, the armature lever is restored to its extreme clockwise position by tension spring 6!, and its movement to that position results in (referring to Fig. 3) clockwise rotation of bell crank I41, and counterclockwise rotation of latching lever I42 in opposition to compression spring I45, whereby the latching shoulder of lever I42 is withdrawn from latching engagement with arm I43 of stop gate I3I. With stop gate I3I unlatched, only its biasing spring (not shown) opposes the torque imparted to cam assembly 58 and its stop arm I32 by shaft 59. The resistance furnished by the biasing spring being relatively insignificant, cam assembly 58 responds to its torque, stop arm I32 escapes from the stop gate I3I by rocking it, and the cam assembly rotates through one cycle during the reception of a code combination.

Periodically in timed relation to the signal impulses armature cam 51 rocks armature lever 3| counterclockwise to bring its armature 4! into engagement with pole faces 26, and if a marking signal is then applied to the selector magnet, the armature 4I and armature lever 3I will be held in opposition to tension spring 3!. If, instead, a spacing signal is then applied to the selector magnet, the armature lever returns to its extreme clockwise position as soon as its follower portion escapes from an apex of armature cam 51. Thus under the joint control of armature cam 5! and selector magnet I2, the selective positions of armature lever 3i corresponding to successive signal impulses are determined. After each selective position is determined, one of the apices of locking cam it rocks locking bell crank 99 to unlock selector lever Bl. When selector lever 8! is unlocked, it responds to any condition of unbalance between springs 533 and I04 resulting from presentation of armature lever 3i in a particular selective position to shift selector lever 81 to a corresponding selective position.

The several selector cam projections T! are arranged with respect to the apices of the locking cam 16 to actuate their associated bell cranks II'I to draw the selector fingers III leftwardly (Fig. 1) after the unlocking, selective setting and relocking of selector lever 37. As each selector finger MI is drawn leftwardly, one or the other of the depending arms I08 of selector lever 81 is presented in the path of the corresponding abutment I2! of the selector finger. If the selector lever occupies a different selective position than it did at the corresponding instant in the preceding signal combination, an abutment I2l will engage an arm IE5 before finger iii completes its leftward movement, and in completing such movement it will be rocked about its disclike portion M6 to shift its free end to the opposite side of the pivotal mounting I22 of T-levers I I2. Upon the restoration of the sword lever I I I to its extreme right-hand position, it rocks the associated T-lever to a new selective position.

In the manner described in the foregoing paragraph, the several T-levers H2 are positioned permutatively in accordance with a received code signal combination. As each T-lever I I2 is positioned in accordance with its code impulse, its associated code disc or code bar (not shown) is positioned permutatively as described in Patent No. 1,745,633 to control the selection of selectable elements.

The leaf spring or spring hinge mountings for the armature lever 3i and the selector lever Bl are employed in substitution for the pivots disclosed in Patent No. 1,937,376 granted November 28, 1933, to W. J. Zenner. Frictional pivots may possibly, under some conditions, suffer excessive wear due to friction, with the result that the desired center of pivotal movement of the lever is not maintained. With the torsional pivots afforded by the flat springs, the rapid alternate clockwise and counterclockwise rocking of the levers is devoid of frictional wear upon the supports for those levers.

Brief mention was made in the detailed description of the invention, of the overlapping of the armature supporting arm and the portion of bracket l3 to which leaf spring hinge 31 is clamped, for the purpose of preventing endwise movement of armature lever 33. It will be observed that when the selector magnet holds armature lever 33 out of engagement with cam 5], spring 6| may tend to rotate lever 33 clockwise about the resilient mounting of armature ii to the extent that flexing of leaf spring hinge 31 would permit. By providing overlapping relation between the armature lever arm 32 and the spring hinge supporting portion of bracket Ill, the attracted armature lever arm 32 cannot rock clockwise upon screw l3 because bracket l3 blocks the end of the lever arm to which the spring hinge is connected. It will be understood that should different interconnections between the armature lever and selector lever than centering springs be employed, or should other modifications be made which might result in tendencies of either of the levers to rock in undesired paths, such tendencies may be obviated by introducing positive blocking relation between adjacent members at the point or points of clamping of the spring hinges in accordance with the principle underlying the overlapping of lever arm 32 and bracket l3.

Although a specific embodiment of the invention has been disclosed and described herein, it is to be understood that the invention is not limited to such embodiment, but is capable of modification, rearrangement and substitution of parts and elements within the scope of the appended claims.

What is claimed is:

In a selector mechanism, a selection controlling lever arm presentable in either of two positions, and a flexible body having a limited portion subjected to flexion for supporting said lever arm for quasi pivotal movement between said positions.

2. In a selector mechanism, a selection controlling lever arm presentable in either of two selective positions, a mounting bracket, and means for supporting said lever arm comprising a flexible member having a portion secured to said bracket and having the lever arm secured to another portion.

3. In a selector mechanism, a selection controlling lever arm presentable in either of two selective positions, a mounting bracket, a clamping block secured thereto, a thin fiat flexible strip having one end disposed between said clamping block and said bracket, and a second clamping block secured to said lever arm with the free end of said strip disposed between said arm and the second mentioned block.

4. In a selector mechanism, a selection controlling lever arm presentable in either of two selective positions, a mounting bracket, a clamping block secured thereto, a flexible strip having a portion secured beneath said clamping block, and a clamping block secured to said lever arm, said flexible strip having another portion secured beneath the last mentioned clamping block, and said lever arm having a portion overlapping said bracket adjacent to the clamping block carried thereby.

5. In a selector mechanism, a selection controlling lever presentable in either of two selective positions, means for biasing said lever toward one of said positions, a mounting bracket, a flexible metallic strip having one end secured to said bracket and mounting at the other end said lever, and means cooperating with said flexible strip for minimizing distortion thereof by said biasing means.

6. In a selector mechanism, a selection controlling bell crank lever presentable in either of two selective positions, a tension spring connected to one arm of said lever to bias said lever to one of said positions, a mounting bracket, a spring strip having one end clamped to said bracket and having the other end clamped to said lever so as to extend substantially normal to the arm to which said tension spring is connected, and means for minimizing endwise movement of said arm and attendant distortion of said spring strip by said tension spring.

7. In a selector mechanism, a plurality of levers to be presented in either of two positions selectively, one of said levers adapted to be positioned subsequently to the other, a pair of depending arms carried by one of said levers in offset relation, a pair of depending arms carried by the other lever in opposite offset relation, and tension spring interconnecting opposed arms of the two levers.

8. In a selector mechanism, a mechanical operator and an electrical operator, a first lever controlled jointly by said operators, a second lever controlled by the first lever, and means interconnecting said levers comprising a plurality of tension springs, one of which is connected to undergo an increase in tension and another of which is connected to undergo simultaneously a decrease in tension upon any relative movement between said levers.

9. In a mechanism including a lever arranged to oscillate between two positions, a bracket for mounting said lever, and a flexible body for connecting said lever to said bracket, the portion of said flexible body intermediate said bracket and said lever being relatively narrow to restrict the movement of said lever to substantially pivotal movement.

10. In a mechanism including a lever arranged to oscillate between two positions, a bracket for mounting said lever, and a thin flat flexible strip secured to the bracket and having the lever secured to the strip in close proximity to said bracket, whereby the motion of said lever is restricted to substantially pivotal movement.

11. In a selector mechanism, a plurality of levers to be presented in either of two positions selectively and in succession, an arm depending from each side of each lever, and spring means distended between each arm of one lever and the opposed arm of the other lever for subjecting one lever to control by the other.

12. In a selector mechanism, a plurality of superposed and generally parallelly arranged levers to be presented in either of two positions selectively and in succession, an arm depending from each side of each lever, each arm of one lever opposing an arm of the other lever, and means disposed between and engaging opposed arms for subjecting one lever to control by the other.

WALTER J. ZENNER.

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