US2373890A

US2373890A - Cipher machine

Info

Publication number: US2373890A
Application number: US232995A
Authority: US
Inventors: Edward H Hebern
Original assignee: INTERNAT CODE MACHINE Co
Current assignee: INTERNAT CODE MACHINE Co; INTERNATIONAL CODE MACHINE Co
Priority date: 1938-10-03
Filing date: 1938-10-03
Publication date: 1945-04-17
Anticipated expiration: 1962-04-17

Description

E. H. HEBERN GIPHER MACHINE April 17, 1945.

7 Sheets-Sheet 3 Filed Oct. 3, 1938 INVENTOR. By EDWARD H HEBERN A TTORNEY April 945. f E. H. HEBERN CIPHER MACHINE Filed Oct. s. 1958 7 Sheets-Sheet 4 oonoaouaonoooonoc j INVENTO.

By E0 wnRo H. HEBERN ATTORNEY April 17, 1945. E. H.'HEBERN 2,373,890

CIPHER MACHINE Filed Oct. 5, 1938 7 Sheets-Sheet 5 INVENTOR. EDWARD H-HEBERN ATTORNEY E. H. HE BERN' CIPHER MACHINE April 17, 1945.

Filed Oct. 3, 1938- 7 SheetsSheet 6 Patents r. W,

Edward iii. Hebern, Oakland, Calif., asslgnor to International Code Machine Company,-Ben Nev., a corporation of Nevada Application October 3, 193a, SeriaiNo. 232,995

6 Claims.

The invention relates to cryptographic machines of the character disclosed in my United States Patent No. 1,861,857, dated June 7, 1932, and more particularly concerns devices for increasing the complexity of coding with codechanging wheels such as those disclosed in said patent.

An object of the invention is to provide a codechanging wheel which provides the operative equivalent of twocomplete alphabets without increasing the number of character circuits to and through the wheel.

Another object is to provide an electro-magnetic means for schematically adjusting the various code-changing wheels of a set thereof in a ciper machine.

A further object is to provide a means for secretly varying the scheme of adjustment of the codechanging wheels of a. set as a further means of increasing the diiliculty of deciphering a message which has been coded with the machine.

Yet another object is to provide an improved means for actuating a typewriter for printing messages as they are coded or decoded with the machine.

An added object is to provide a means whereby different characters represent spaces in a code message, yet may be automatically decoded as spaces in the decoded and printed message.

' The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth Or be apparent in the following description of a typical embodiment thereof, and in the following drawings, in which,

Figure 1 is a plan view showing a cipher mamachine, certain members of the structure being removed and others broken away.

Figure 6 is an enlarged fragmentary and sectional view taken axially of a clamping bar assembly shown in Figure 5. s

Figure 7 is a fragmentary sectional elevation at l-l in Figure 5.

Figure 8 is a sectional elevation at 8-8 in Figure 5.

Figure 9 is a fragmentary section at 9-9 in Figure 5.

which the keys of the typewriter are arranged to be individually actuated by character circuits controlled 'by the coding machine, the connector for the cipher machine being shown as engaged therewith.

Figure 3 is a perspective view showing the operative relation of a key-operating electromagnet to a. keybar of the typewriter of Figures 1 and 2.

Figure-4 is a perspective view illustrating another possible relation of a key-operating electromagnet to a keybar of the typewriter.

Figure is an enlarged plan view of the cipher Figure 10 is a ,plansectional view taken at the broken line Ill-Ill in Figure 8 and generally be low the members shown in Figure 5.

Figure 11 is a fragmentary sectional elevation at ll-ll in Figure 10.

Figure 12 is' a plan'view of a unit for controlling the adjustment of the code wheels of the machine.

Figure 13 is an elevation at l3--l3 in Figure 12.

Fi ure 14 is an outer end view of the unit of Figure 12, 1

Figure 15 is an elevation at l5--l5 in Figure 12. v

Figure 16 is a sectional elevation at I6--l6 in Figure 12.

Figures 17 and 18 and 19 are fragmentary sectional elevations taken at diflerent planes in Figure 12 to show successive switch assemblies.

Figure 20 is a perspective view of a unitary rotary assembly of Figures 5 and 12 and 13.

Figures 21 and 22 are perspective views of a code-changing wheel viewed from opposite sides thereof.

Figures 23 and 24 are opposite end face views of the code wheel of Figure 21.

Figure 25 is a section atthe broken line 25-45 in Figure 23.

means and circuits shown in Figure 28, the switch elements being related as for decoding.

The present cipher machine is arranged for operation in response to the selective actuation of keys in the general manner of a typewriter to code or decode a message and appropriately actuate a printing or typewriting machine 3| which actuated from the machine 30. The mechanism of the latter machine is mounted on a frame which comprises a base-member 32 of rectangular outline enclosing and supporting complementary and transversely spaced side plates 33' and 34 which are rigidly connected by a plurality of spacer bars 35, certain of said bars being further nism as will be brought out. An array of three rows of keys for selective depression is provided at a keyboard portion of the frame forwardly of the front edges of the

frame sides

33 and 34.

As shown in Figures 1 and 5,-the keys at the keyboard include twenty-six character keys 35 each representing a different letter of the English alphabet and also a numeral or punctuation mark or some other character of a second set of characters. The keys 35' of the typewriter 3| correspond to the keys 35 of the unit 35, and the printing of one or the other of the two characters represented by a particular key 35 is determined by the position of a usual paper-carrying carriage (not shown) of the unit 3|; when the carriage isin a normal lowered position thereof, the alphabet characters are printed, and the characters of the other set may be printed when the carriage is in the raised position therefor. As is usual, the

of more than one of the

keys

35 and 45 at a time;

utilized in connection with the machine mechacarriage of the typewriter 3| would be controlled by an escapement to release the carriage for its movement through the space of a. character after character has been printed.

A'suitable means (not shown) is provided in characters of the second set,- and a key 31 is provided at the keyboard of the unit 35 for actuation to operate the carriage shifting key 31' of the typewriter 3| to ffect a raising of the carriage when desired. Said second set of characters might, of course, be alphabet letters of anotherreal or imaginary language. A character-spacing key 45 is also provided at the keyboard of the cipher machine 30, while a corresponding key 45' is provided at the keyboard of the typewriter 3|.

By particular reference to Figures '7 and 8 and 10, it will be seen that the

keys

35 and 31 and 40 are carried at the forward ends of and generally above keybars 38 which-pivotally engage a common shaft 39 which is fixed to and between the

frame sides

33 and 34 at the general level of the keys, and is parallel to the front line of the unit. As shown, each keybar comprises a flat, strip of metal having an ear portion ,38' extending radially downwardly-of its pivotal axis and having its extremity connected by a tension spring 42 with a frame bar 35 which underlies the keybars 38, said spring being constantly operative to urge a raised positioning of the keybar to engage an overlying frame bar 35 as a stop means for the keybar. v

In the present instance, eac keybar 38 has a rearward .extension 35" whic engages a slot 43 provided in a plate member 44 which is fixed in upright position to a frame bar 35 which underlies the extension. The frame bar 35 which provides the anchorage for the springs 42 carries a slotted plate 45 similar to the, plate 44, with said bar operative as a stop to limit'the downward swinging of the keybars. It will be noted that the keybar-receiving slots of the

plates

44 and 45 are evenly and similarly spaced along the plates, extend to the top plate edges, and function as a guiding and positioning means for the keybars in their places.

Means are provided to prevent thedepression the unit 3| for raising it carriage for printing bar 54. The other arm 58 of the lever 51 is arthat the keybar 38 of only one of the

keys

35 and 45 may be depressed through their line at any time. The under edge of the keybar 33 for the shift key 31 is notched out or otherwise formed above the line of the balls 41 wherebythe depressing of this keybar is permitted without engaging the balls beneath it; in this manner, the selective depression of the remaining keybars is permitted for effecting the printing of characters of either set, since the depression of the keybar for the shift key 31 does not spread the balls in their line. I

i A shaft 45 is ioumalled in and between the frame sides 33 and 34 in parallel relation to the keybar pivot shaft 39. Arms 43- and 50 extend forwardly from the shaft 43 in mutually coplanar relation, are rigidly fixed to the shaft, and carry a straightbar 52 in and between their front extremities. The bar 52 is arranged in normally engage the under edges of all of the keybars 38 except that for the shift key 31 by the action ofa tension spring 52' which is operative betweena forward point of the arm 49 and an overlying frame bar 35. When a keybar for the keys 3501" shaft 48 and efiect an upward swinging of an arm 53 which extends generally horizontally from the shaft at the opposite side from the frame arms; in the present instance, the arm 53 comprises an integral extension of the arm 39.

A thrust bar 54 extends upwardly from a pivotal connection with ,the arm 53, and its rear edge is stepped to provide an upwardly facing shoulder 55 for normal positioning beneath the forward arm 55 of a lever 51 which is pivoted to the frame end 33 and is substantially perpendicular to the ranged for movement against a spring contact arm 50 of an electric switch 5| to dispose the contact 52 of the arm 50 out of engagement with a fixed contact 53 of the switch assembly. The

switch contacts

52 and 53 are suitably insulated from each other and the frame and the lever arm 58 for the connection of the switch 5| in an ungrounded circuit; as shown, the switch parts are mounted on a support of insulating material which is fixed on the plate 33 and mounts terminals 52' and 53' connected with the

contacts

52 and 53 respectively for their use in connecting the switch 5| in a circuit.

A tension spring 54 is normally operative between-the lever arm 55 and an anchorage on the plate 33 to overcome the resilient, resistance of the switch arm 55 to open .the switch 5| and engage the arm 55 against a stop pin 59 which underlies the outer arm end and extends from the plate 33. When the shoulder 55 of the bar 54 is raised beneath the end of the lever arm 55 to sufllciently rock the lever 51, the spring arm 55 of the switch BI is permitted to, engage its contact 52 with the contact 53- and so close the switch thereat. A tension spring 551s normally operative against the bar 54 to engage the rear faceof the bar below the shoulder 55 with the stop pin 53, the rear face portion of the bar 54 asrasoo above the shoulder being held clear of the opadjustment of a plurality of code-changing wheels of the coding and decoding mechanism ofthe unit 33 through the energizing and actua-' tion of an electromagnet means which is arranged to effect the operations of pawls against ratchet teeth of the wheels to reset one or more wheels after the temporarily closed circuit'there- I of has been opened. Since-holding down a character key would prevent a completion of the de- I sired action until the key is released, means are provided for automatically opening the control circuit after the electromagnet means has been actuated and independently of the disposition of the actuating key, said means efiecting a rocking of a lever 51 pivoted on the plate 33 to apply a depending lever arm 68 laterally against the upper end of the operative bar 54 to swing the latter wardly and fixedly from the hub Band has its free end connected to the free end of an upwardly extending arm I2 of the lever 65 by means of a link 13 which is pivoted to both arms.v The hub 69 is provided with a depending arm 14 which is fixed thereto and has its free end linked to the armature 16' of an electromagnet 16, said armature comprising a movable magnetic core for the solenoid 15 of the electromagnet and being normally extended from the core bore in whichit is slidable for its axial movement within the bore when the coil 16" is energized. The coil 15" is connected in the same circuit with the switch GI, and the rocking of the hub 69 which is caused as the armature I5 is displaced by the energizing of the coil is arranged to operate through the link 13 to rock the lever '61 to displace the arm 54 to free the lever 56 and so open the controlling circuit at the switch 6| in the described manner and just as the inward stroke of the armature is completed. It will be noted that the return movement of the arm lit permits the engagement of the rear face of the arm 54 below the shoulder 55 to en age the lowered extremity of the lever arm 56 until the bar is lowered to dispose the shoulder below said arm. 'With the described arrangement, the continued operation of the code wheel control in a cycle of operations thereof is independent of the disposal of a control key which was originally depressed to initiate the cycle.

A unitary code wheel assembly I1 is mounted at and across an upper portion of the frame of the cipher machine 20. .As is particularly brought out in the assembly showings of Figures 1 and 5, the assembly 11 comprises end plates I8, brushments 80 are cylindrical in outline and are provided with axial boresfor receiving a shaft 83 for their mutually independent rotative 'adjustments about the shaft, said shaft engaging complementary bores. provided in the various. plate members 18 and I9 and 8! toprovide a fixed alignment of the various members of the assembly and providefor the rotation of the elements 80 in their places. The shaft 82 is mounted for its removal axially thereof from an unobstructed end of the assembly 11. v

The various plate members 18 and I9 and at all have correspondingportions thereof extending radially beyond the elements 80, and clamp assemblies. including spacer sleeves 84 of appropriate lengths to properly space the plate members are engaged through said extending plate portions for securing the plates in mutually' spaced relation while providing for the rotation of the elements 80 in their places. As particularly'shown, two lower assemblies 83 extend through and between the frame plates 33. and 34 for mounting the code wheel unit ll onthe frame,

I and these assemblies also mount and clamp in place a unitary assembly 86 for controlling systematic adjustments of the code wheels 80 in a manner to be hereinafter described. The assemblies 83 are so disposed that the code wheels released by the removal of the shaft 82 may be removed for reversing them in place and/ or varying their order in the code wheel assembly, or.

replacing one or more of them with other wheels of different internal arrangement of conductors. By reference to Figures 1 and 5 to 8, it-will be noted that each clamp assembly 83 includes a rod 83' having its endsfixed to the extreme elements to be connected. As shown in Figure 1, the upper rod 83 has its extremities engaged in complementary sockets provided in the plates 18 and secured in place by screws extending axially into the rod ends through the plates. Each of the lower rods 83' has its extremities seated in complementary sockets in the

plates

33 and 34, and is secured to the plates by screws extending through the plates into threaded axial bores in the rod ends, the structure and relations being shown in Figure 6. Collars 85 are adjustably fixed by setscrews 85' on the lower rods 83 opposite the outer elements of the units 11 and 86 to be fixedly mounted in place on the machine 30, and at least one collar 85 threadedly carries a thrust ring 85" for movement against the opposed element and toward the other collar to clamp the assembly of engaged and intervening elements in place; in this manner, the units 17 and 85 are adjustably mounted and releasably fixed between the frame sides, namely, the plates 33 and 3t.

It will now be noted that the present code setting. By particular reference to Figure 5 and carrying plates 19 engaging each of the end plates vI8, four similar code wheels 80 rotatably mountedbetween the plates and individually numbered Figures 21 to 26 inclusive it will be seen that 39" which is arranged to receive the pivotshalt 82 for rotation thereabout. The wheel as may be of metal, and the rings 81 are preferably molded of an electrically non-conducting material having contacts 88 embedded therein during their molding to have their exposed faces flush with the outer ring faces thereat.

The contacts 88 of each ring 81 are equally spaced in a circle which is concentric with the axis of the shaft 82, are twenty-six in number, and are normally in simultaneous engagement with spring contact brushes 9I which extend from the opposed faces of the plates 19 and BI. As shown, the brushes. 8i comprise spring arms extending radially outwardly from secured inner ends thereof and having their free ends arranged for simultaneously engaging the opposed faces of the contacts 88 in their line. Each contact 88 of a ring 81 of a code wheel 88 is connected by means of an insulated conductor 93 with a contact 88 of the other ring 81 of the wheel structure, the ratchet wheel portion 89' between the rings and the hub 89" being transversely perforated to permit this. It will be understood that the connections through the code wheels may be made in a great number of different combinations whereby such different combinations in themselves comprise a code-varying device, as is brought out in my said previous patent.

In the present code wheel structure, each contact 88 is elongated in its line, and the two sets of contacts on each code wheel 88 are so related that an axial line through the forward end portion of one contact extends through the rearward end portion of a contact at the other side of the wheel, the line being one through mutually opposite contact points of the brushes 9I when the wheel is in a set position thereof. In this manner, when a brush 9I moves from one contact point of a given contact 88 to the other contact point thereof, different connections are provided through the wheel. Accordingly, the present code wheels 88 are each provided with fifty-two ratchet teeth whereby one revolution of a wheel is the coding equivalent of two revolutions of a code wheel having contacts which are engaged successively with a given brush. Besides reducing the rotary movement which is required for a changed setting of a code wheel, the present arrangement markedly increases the undecipherability of a, coded message in terms of the number of wheels in the code wheel assembly, it being understood that such a, number may be one or more in accordance with the use requirements of a particular situation.

It will be noted by reference to Figure that corresponding brushes .9I at opposite sides of each brush plate 8I are electrically connected by a rivet or the like which secures the brushes in place. Also, securing bolts for the brushes of the plates 19 extend through these plates to individual terminal plates 94 for connection in different character circuits which are to control the actuation of the typewriter 3|. Preferably, and as shown, each end plate 18 of the code wheel assembly is hollowed out at the face thereof which opposes the adjacent brush plate 19 whereby to provide a space for the wire connections to and from the terminals 94.

The described connections within the code wheel assembly 11- are understood to provide twenty-six closed electrical paths therethrough,

said paths being varied each time one or more code wheels 88, is rotatively adjusted through the angle of adjacent ratchet teeth thereof. For'reference, the connectors 94 may be lettered in terms of their connections with sending keys and the keys of a printing machine; for example, the connector A of the left-side plate 18 might be connected with the A circuit of the cipher machine 38, while the connector Q of the right-side plate 19 might be connected with the Q circuit of the typewriting or printing machine 3|; t Should it happen that said A and .Q connectors are joined through the code wheel assembly 11, the character Q would be printed for A when the A key 38 is struck, this being assumed in the diagram of-Figure 28. If now, the connections provided at the connectors 94 are reversed with respect to the two machines, the striking of the letter Q at the cipher machine keyboard will print the letter A which was originally coded to the letter Q; it will thus be understood that the provision and use of a set of reversing switches and the setting of the code wheels is all that is needed for effecting coding and decoding of the same message with the present equipment, it being noted cipher machines.

that the peripheries of the code wheels 88 carry the letters of the alphabet opposite alternate ratchet teeth for use as indicators in setting the wheels at the start of coding or decoding a message with respect to a reference mark 95 which is provided across the fronts of the fixed plates 18 and 19 and i9 of the code wheel assembly 11.

It will now be noted that the depression of a particular character key 36 to rock its keybar 88 for effecting the closing of the switch 8| is arranged to simultaneously close a normally open circuit through the code wheel assembly 11 for that character only. As shown in Figures 8 and 10 and 28, a projection 98 extends upwardly from each keybar 38 to normally engage a spring switch arm 91 to hold the same out of contact with a fixed and elongated conductor element 98 which underlies the spring arms 91 for all of the keybars and is connected by a conductor 99 with a terminal I88 of an electric power source E such as an electric battery, the other power terminal being designated by the numeral IN. The arms 91 for the keys 36 and the common contact 98 are understood to provide a. multiple switch for controlling parallel branch circuits for the different characters, and these elements are shown as mounted on a base which comprises a bar of insulation material which is in turn mounted on the frame bar 35 which acts as the stop to limit the upward swinging of the keybars,

The various switch arms 91 for the keys 88 are each connected by independent conductors I83 with the input terminal I85 of a, reversing switch I84 which provides connections for either coding or decoding a given letter with the same or like Connected pairs of reversing contacts I86 and I81 of each switch I84 are respectively connected with terminals 94 of the different end plates 19 of the code wheel assembly 11 by means of conductors I88 and I89, and an output conductor III leads from the output terminal I I2 of each switch I84 to a connection with a different key-operating means for the printing machine 3 I. As is particularly shown in Figures 5 and 8 and 9, the switch input and output terminals I85 and II! respectively are provided at the under side of a plate member I18 which is fixedly supported on a pair of the frame bars 35 which are disposed forwardly of the code wheel assembly 11. The terminals I85 and H2 are respectively connected through the member II3 with sets ofspring contacts H4 and II 5 which tend to extend upwardly from the member, with the contacts of each set arranged intwo parallel to a substantially unlimited degree the particular rows of thirteen each and equally spaced in their rows.

A plate member I l B is slidably supported above the fixed plate member llt for its limited movement in a direction parallel to the rows of spring contacts Ill and lid of the latter, said member being laterally guided in its movement between an upper pair of the frame bars 35. The member H8 carries contacts I06 and lfl'l equally spaced in rows thereof overlying the lines of the spring contacts lid and lid respectively and the member H8 is supportedon said contacts whereby either set of alternate contacts we and ldl of each row may simultaneously engage the spring for connecting the conductors ltd and its with the contacts ltd and it? are provided at the up- .per side of the member lid, and each said terminal is connected with contacts ltd and Bill in adjacent rows thereof which are opposite the spring contacts lid and lit, the arrangement being such that the latter contacts engage the terminals ltd and ldl respectively when the member lid is in decoding position thereof, as in Figures 5 and 8 and 9 and 10 and 29, and are connected with the terminals Bill and int respectively when the member i it is in its coding position as in Figure 28. A generally erect arm lid is pivoted on the wall 36 for its movement in an upright plane rallel to the lines or the reversing switch contacts, and is connected with the opposed end of the member lit for its use in moving the member between limiting positions determined by adjustable stop members lit mounted on the plates t8 and 3d, whereby to respectively provide the switch connections for coding and decoding with the present cipher unit.

A unitary casing member Bil having a front wall m2, side walls lit, a back wall tit, and a top wall lZh is mounted on the frame base 32 for generally enclosing the described mechanism. The top wall I25 the casing lil is disposed at a level below the rotary axis of the code wheel assembly and is slotted across its width in the line of said assembly to permit the protrusion Of the latter. A slot in the top casing well lit receives the setting arm lid of th described multiple reversing switch for-its manual engagement to shift the member between its limiting positions which are detered by its engagement with the members me. A pointer ltd extending upwardly V opposite ends of the member and selectively en-' gagedble with spring contacts lid and ltd respectively mounted on the plates 3d and as the member is disposed for a coding or decoding use of the machine. The single-pole switches til- I28 and ltd-tit thus provided are respectively operative in circuits which cause the printing of i a character for a message space in the coded message, and cause the provision of a space for each code character which represents a space in the original message when decoding is efiected, the specific control being hereinafter described.

Recalling that one or more of the wheels 80 are to be reset between the printing of successive coded or decoded characters, and that my beforementioned patent provided for an automatic and progressive setting of, a set of code wheels mechanically, and in an unchangeable order, an improved means. is provided for secretly varying order iii which the various code wheels are advanced as a message is coded or decoded. The

present means is electrical and essentially pro- 5 vides a control for independently operative electromagnets l3l having armatures l3l' which actuate dogging hooks or pawls teeth of the code I wheel ratchets st to rotatively advance the same each time the solenoid ill!" of an electromagnet ltl is operative to move its armature out of its normal position.

By reference to the drawings, and particularly to Figures 8 and i0 and 11, it will be noted that four electromagnets it: are mounted in a conimon plane below the diflerent code wheels and the level of the shaft 68 with their axes parallel to the .planes of the code wheels. The armatures l3l' extend'rearwardly from the solenoids ldl" and are suitably/guided for their rectilinear reciprocation in the solenoid bores. Brackets 532 mount the lectromagnets l3l in fixed position on a pair 0 spacer bars 35. As illustrated, the structure and mounting of the electromagnet E6 is the same as that of the electromagnets I8 I, the former is mounted similarly in the same. plane and line with the latter, and the mutual spacing of the electromagnets in their line is uniform.

Links I33 connect each armature ltl' with the lower end of an arm ltd which depends from a m sleeve member E which is rockably mounted on i the shaft 68, the sleeves being mutually independcut and disposed along the shaft to position the arms lid for action in the lines of the armatures l ti. Arms l36 extend upwardly from the sleeves 35 M5 in fixed angular relation to the arms ltd, and

pivotally carry levers I31 having pawl arm portions extending forwardly of their pivot points and terminating in pawls I39 which are arranged to normally engage between teeth of the ratchets 89 of the various code wheels through the action of tension springs Ml which are operative between the rearward lever portions and radial ears M3 extending generally rearwardly from the sleeves l35. A tension spring Mt extends fortlt. wardly from each arm lit to a connection with the rear end of an anchor rod ltd which is slidably engaged through the frame bars 35 which support the reversing switch base i It and threadh edly carries a nut. M6 which bears against the forward supporting bar 35 to provide for an adjustment of the tension of the spring ltd. The spring ltd is normally operative to engage the arm ltd with the rearward frame bar 35 as a positive stop and a positioning means for the assodd elated p wl ltd.

, In the presentinstance, the pawls I39 are each so shaped that their rearward movements permit their swinging radially over the ratchet tooth immediately to the rear thereof to engage its point go behind said tooth, whereby a return movement of the pawl may rotate the ratchet and its code wheel through the angle between adjacent teeth, This action of a pawl results each time an electromagnet ldl is energized to displace its armature from its normal position in which it is yieldingly held by the spring I, and any adjustment of the engaged code wheel occurs after the depression of a key 36 and following the transmission and termination of the coded impulse through the code wheel assembly to actuate a. key 36 of the typewriter 3|. While the friction of the contact brushes 9| with the opposed code wheel contacts 88 may generally be relied on to secure the code wheels against a backward rotation when a l5 pawl laa is pulled rearwardly under a ratchet of pawls m and I62.

wheel tooth which it contacts, it will be understood that an oppositely acting pawl might be provided for thepurpose, such a pawl being re- 'leasable when a code wheel is to be set in an initial ciphering position.

The unit 96, it will now be noted by reference to Figures and 12 to 20 inclusive, comprises a pair of opposed and transversely spaced similar plates I5I and I52 which are held in parallel relation by a fixed shaft member I53 and spacing bars I54. Mutually aligned notches I55 are provided in and across the bottom edges of the plates for fittedly receiving the two bottom clamp elements 83 therein, suitable spacing sleeves I58 being mounted on the elements between the plates I.5I and I52 and at the outer sides of the plates whereby a tightening of the thrust rings 85 of said clamp elements may releasably secure the unit 86 in place without crushing it. When the unit 86 is' mounted in the position-shown, the shaft I53 thereof is arranged to be in axial alignment with the shaft of the code wheel assembly as is shown in Figure 5.

The shaft I53 rotatably mounts two unitary assemblies I51. and I58 which are arranged. to be independently rotated through small angles each time the 'electromagnet 16 is energized by reason of the closing of the switch GI and a switch 91- 98 when a key 38 is actuated. As is brought out in the drawings, the assemblies I51 and I58 respectively include ratchet wheels I59 and I66 which are in the form of flat and centrally perf forated discs, and are arranged for simultaneous one-way rotative'adjustments through the actions As is shown in Figures .10 to 13, the pawls I6I and I62 are provided at the forward ends of levers I63 and I64 independently pivoted to the upper ends ofarms I65 and I66 extending radially upwardly from the hub 69 which is rocked by the electromagnet 16 each time the switch 6| is closed to energize the electromagnet. Springs MI and I44 are respectively operative against the arms I65 and I66 and against the pawl levers I63 and I64, as in their applications to the levers I31 and the arms I36, whereby the pawls I6I and I62 are arranged to operate against the teeth of the engaged ratchet wheels in the same manner as the pawls I39 operate against the ratchet teeth of the code wheels.

It will now bevnoted that the assembly I51 comprises a hub member I68 which is rotatably mounted on the shaft- I53, has an intermediate radial flange I68, and carrie circular discs I69 and I16 fixed against opposite sides of its flange I68. A cylindrical member "I has an end engaging the disc I16 'at its face opposite from the flange I69, and has the ratchet disc I59 engaged against its other face. Bolt I13 engage through the ratchet disc I59, the member "I,- the disc I16, the flange I68 and the disc I69 for unitarily fixing the various elements together to tain the shanks of headed pins I in variable number and arrangement, the shank portions of the mounted pins being exposed between their heads and the opposed disc face, and the disc periphery is provided with fifty-two equally spaced ratchet. teeth for operative engagement by the pawl I6I. The member "I bears indicia for the twenty-six letters of the English alphabet in order about its periphery and is provided with one transverse notch I16 in said edge, preferably at the position of the character Z. The

di cs I69 and I16 are of like size and are each provided with twenty-six notches I11 in their peripheral edges, said notches being relatively staggered peripherally of 'the two discs, as is brought out in Figures 12 and 20.

The assembly, I58 comprises a hub member I18 rotatably mounted on the shaft I58 and having an intermediate radial flange I19, and carries the ratchet disc I68 against one side of the flange. A circular disc I86 engages the other side of the flange I19 and is followed by a spacing ring and a circular disc I82 in order. Screw bolts engage through the disc I82, the spacing ring, the disc I86, the hub flange I19 and the ratchet disc I66 for unitarily fixing the various members together to provide the assembly I58. The periphery of the ratchet disc I68 is provided .with flfty teeth for operative engagement with the pawl I62, and the periphery of the disc I82 is provided with a single notch I88. -The periphery of the 'disc I86 is provided with a succession of nine notches I85 which are thirtysix degrees apart whereby the end notches of the line are seventy-two degrees apart in the peripheral circle, and the disc I86 is so set with respect to the disc I62 that the center of its l It will now be noted that the various disc members of the assemblie I51 and I56 are of substantially the same diameter, and are arranged to variably and independently control the conditions of six different switches HI and I92 and I93 and I94 and I95 and I96 through the respective actuationsthereof by members 2M and 262 and 263 and 264 and 265 and 266 rockably mounted on a spacing bar I54 which is forward of the shaft I53. As shown, the six switches respectively comprise spring contact arms I9I to I96 inclusive mounted on the under side of a common. base member I91 of insulating material carried on a spacer bar I54 and normally engageable with a common contact I98 which comprises a flat plate of conducting material mounted at the rear side of the base I91 in upright position and arranged for the engagement of the spring contact arms with its under edge to close the corresponding switches. Opposite the ratchet disc I59, the common contact plate I98 is provided with a downwardly extending L-shaped extension I99 arranged for the engagement of the spring contact arm I9I' with the upwardly directed edge thereof.

The present switch-control members 26I to 266 inclusive each comprise bell-crank levers having upright arms providing points for respectively engaging the pins I15 on the ratchet disc I59, the notch I16 of the cylinder I1I, the notches of the disc I16 and I69, the notch I63 of the disc I82, and the notches I 84 of the disc I86 as the engaged elements are rotated. Generally horizontal arms of the said control members are engageable with the extremities of the different switch arms I9I' to I96 inclusive for swinging the latter to open their circuits at the common contact plate I98, and tension springs asvasoo 201 are constantly operative against the coning point 20I of the member lies in the path of movement of the shanks of the pins I15 on the disc I59, the switch I9I being held open except when a pin I15 engages the lever point 20I'. When the rotary adjustment of the disc I59 engages the shank of a pin I15 with the point 20I',

the latter is deflected outwardly with respect to the disc axis to rock the member 20I to close the switch I9I at the extension I99 of the member I99 during that setting of the disc. Since the pins I75 may be mounted on the disc I59 in any number and arrangement. the times and frequency of-closing of the switch I 9| in each rotative cycle of the disc may be varied at will. The-sockets I19 may be numbered or otherwise differentiated whereby the pins may be placed therein in any predetermined number and arrangement.

By reference to Figure 16, it will be noted that the switch I92 is arranged to be held open except while the point 202' of the member 202 engages the notch I15 of the cylinder Hi, the latter occurring but once in every fifty-two rotary adjustments of the cylinder. The twenty-six notches of the discs I10 and I69 are arranged to receive the points 203' and 204' of the members 203 and 200 respectively at every other setting of' the discs and alternately with respect to the discs whereby, as will be evident from a consideration of Figures 14 and 15, the switches I99 and I99 will be alternately closed and open for successive settings of the assembly I51.

Referring to the switch control assembly I58, it will be noted by reference to Figures 12 and 18 and 19 that the point 205' of the member 205 engages the notch I85 of the disc I82 once in every complete rotation of the assembly by the. pawl I 02 to then permit a closing of the switch I95. Also, the point 205' of the member 205 engages a notch I80 of the d sc I80 to close the switch I91 nine times in each rotation of the assembly I58. Since the ratchet disc I69 has two less teeth than the ratchet disc I59, the assembly I50 will be rotated at a faster rate than the assembly I51 as the pawls IBI and I02 are rotated together by the electromagnet 19. It will be understood that the switch ranged to be closed in lieu of the switch I90 once in each revolution of the assembly I58.

The assemblies I51 and I 58 may be frictionally and releasably retained in successive set positions thereof as by the engagement ofspring-pressed detent rollers 209' in the notches defined between the teeth of the ratchet discs I59 and I50. As shown, the rollers 209' are carried at the ends of upright arms of bell-crank levers 209 similar to the members 20I to 206 and mounted on the same frame bar I54 springs 2| being operative against the other lever arms to yieldingly urge a retention of the'respective rollers in the notches of the discs. It will be noted that the separate driving of the ratchet discs I59 and I60 of the two assemblies permits independent and predetermined initial settings of the assemblies I51 and I58 with reference to the mark 95 to which the code wheels 80 are initially set.

The contact bar I98 for the switches I9I to 195 inclusive is connected to the same battery I95 is arterminal I00 as the bar 98 by means of a wire 2I5, and the switch arms I9I' to I94 inclusive are respectively connected with plug-receiving sockets 2H and 2I2 and 2I3 and 2 which are provided in a front casing member 2I1 of the control unit 86. As shown, the member 2" is fixed to the forward ends of the side plates I5I and I52, and a plate 2I8 overlies the top edges of the plates SI and I52 and extends rearwardly to the disc assembly of the unit 86 to cover the switches and the control lever therefor.

The sockets 2| I to 2M are arranged to interchangeably receive single-contact connector plugs 9 carried at the extremities of flexible conductors 22I which extend from a terminal of each of the solenoids I9I" of the four different electromagnets I3I; it will be recalled that the armatures of these electromagnets are separately operative when energized for rotatively adjusting the different code wheels 00 by actuating the pawls I99 in the described manner.

much increases the secrecy of coding, it being noted that the connection may be left open for one or more of the electromagnets if desired to further vary the scheme of advancing the code wheels.

By .particular reference to Figure 28, it will now be noted that the other terminals of the electromagnets I3I are connected by a common conductor 222 with a fixed contact of a normally open electromagnetic switch 229 which has its other switch contact comprising an armature 223' connected with theterminal 52' of the switch BI by means of a conductor 225. In the present instance, the armature 223' of the switch 223 is disposed to close the circuit which includes it against the resistance of a spring 220 and only when the arm-controlling solenoid 223 is energized. One terminal of the electromagnet 16 which controls the switches I9I to I95 in the described manner is connected with the conductor 222 by means of a conductor wire 226, while the other terminal of said solenoid is connected to the battery terminal IOI through the bar I98 by a connecting wire 221. The arrangement is understood to provide mutually parallel circuits for the electromagnets I5 and I3I between the battery terminal I00 and the switch 223, all five circuits being controlled jointly by the electromagnetic switch 223 and the mechanically operated switch M which are in series with the other battery terminal IOI.- Since the switch 6| is also included in the coding circuit, coding and code wheelshifting may only occur as successive oper-- ations following the closing of a character circuit by the depression of a character key, and the switch BI thu constitutes a master switch-and may be so referred to.

As is shown in Figures 1 to 4 and 28, the typewriter or printing machine 3| is provided with a key 229 for depression to effect a return move -ment of the carriage and an advance movement of the print-receiving sheet at the end of a line of typing by means which are well known in the typewriter art. The machine 3I may be a usual one arranged for the solely hand oper- 'ation of its keys, but I prefer an electric typewriter wherein a slight manual displacement of a key causes the completed actuation of th key by electrical-means, reference being made, by way of example, to an electrically operated typewriter known as the International; by the use of the latter class of typewriter, the character circuits This interchangeable connection for the electromagnets I3! very.

of the present cipher apparatus may directly supply enough power to actuate the keys of the typewriter.

Individual electromagnets 23I of similar structure are provided for selectively effecting depressions of the various keys 39' and 31" and 49' and 229 of the typewriter 3| when their circuits are energized. In the present instance, the various keys are carried at the forward ends of similar keybars 230, and movable armatures or cores 232 of the electromagnets 238 are suitably connected with the keybars for depressing them to cause the printing of characters when the solenoids of the electromagnets are energized. As shown in Figures 2 and 3, armatures 232 which normally extend upwardly from the bores of the solenoids for movement into the cores when the solenoids are energized carry hooks 234, which engage over the keybars' 230 to normally support the armatures 232 in raised position in their solenoids. An alternative arrangement would be one in which a push rod 234" depends from an armature 232 which is engaged in a solenoid 233which is supported above a key to be depressed for printing, this arrangement being indicated in Figure 4. In either event the various solenoids 233 would preferably be provided as a unitary set thereof for fixed mounting on the typewriter 3|; in Figure 1, the solenoids 233 are shown as mounted on a common base plate 235 which is in turn secured beneath the typewriter 3 I By reference to Figures 1 and 28, it will be noted that the various control circuit wires to and from the typewriter 3I are grouped and carried together in a common conduit 231' and terminate at a multiple connector head 238 for detachable connection with corresponding terminals 239 of the solenoids 233 by which the various'character keys of the unit 3I are controlled. The output wires III. of the reversing switches I04 are continued through the connector-238 to terminals of different character-printing solenoids 233, the other terminals of the same solenoids are connected by a common return wire 24I to one terminal of the solenoid 233" of the electromagnetic switch 223, and the other terminal of the latter solenoid is connected to the wire 225.

With the described connections, the closing of the switch 223 to actuate the wheel control unit 86 is arranged to be efiected only when the switch 6| has been closed by the depression of a character key at the keyboard of the cipher machine 30 to simultaneously close a character circuit. It will be understood that the mechanical closing of any character circuit through the code wheel assembly 11 and the simultaneous mechanical closing of the switch 6| causes the energizing of a character circuit in accordance with the key which is actuated to operate an appropriate key ofthe typewriter while the pawls IBI and IE2 are being moved to operative positions with respect to the ratchet wheels I59 and I60 respectively of the unit 96 by the action of the energized solenoid I6. Also, a solenoid I3I' connected bya wire 22I with -any one of the switch arms I9I to I94 which engages the contact I98 will be energized to similarly shift its pawl I39 with respect to the ratchet of the code wheel 80 which it controls; in the present instance, solenoid circuits are normally closed alternately at the contacts I93 and The carriage return circuit, which has no control key at the cipher machine keyboard in the present instance, include in order the wire 2I5, the common contact I98, the switch arm I95, a wire 244 leading through the connector 233 to the solenoid 2 33r which controls the key 229, and a wire 245 from the other solenoid terminal to the wire 243 to complete the circuit to the battery E. Since the disc I82 is disposed to close the carriage return circuit only after each fifty char .acter impulses have acted to print characters in coding, the arrangement is understood to operate only at the end of each line of printing to dispose the typewriter carriage and the Paper thereon for receiving a succeeding line of printing.

Recalling that a typewriter carriage automatically shifts for the space of one character following the printing of a character, and that the notches I85 of the disc I80 are operative after each five character impulses, except when the carriage shift circuit is energized, to temporarily engage the spring. contact I96 with the contact I98 toclose the spacing circuit thereat, the present device is operative to effect an extra space shift of the typewriter carriage, provided the circuit for the solenoid 233-3 which is operative to actuate the spacing key 40' is otherwise closed. In this manner, the characters of a coded message may be printed in groups of five in their line, this facilitating decoding since an operator may readily remember a succession of five code characters and keep his place in the copy while he is operating the cipher machine for decoding the typed coded message. It will be understood that the omission of a notch I85 from the disc I80 in the axial line of the notch I84 of the disc I82 provides for the carriage return action in lieu of an extra space shift at this point in the operative cycle of the two discs.

By reference to Figure 28 wherein the reversin switch element IIIi is in coding position, it will minal of the solenoid 233--s which is arranged for energizing to actuate the spacing key 40' of the typewriter 3I, and the other terminal of the solenoid 233-s is connected by a wire 25I with the wire 243 leading to the battery terminal IIII. It will be understood that the arrangement is such'that no control of the spacing key 40 is provided at the cipher machine keyboard during coding, and that the described group spacing of the printed characters is provided only when the I94 whereby the solenoids connected with said switch 241 is closed. The switch 241 is shown in Figure l as mounted on the top wall I25 of the casing I23 for its ready accessibility to the operator.

' It will now be particularly noted that the wire 243 provides a common connection from the solenoids 233u and 233-s and 233-r directly to the battery terminal IBI whereby the energizing of one or more of these solenoids may follow the de-energizing of the solenoids 233--c which control the character keys 36' of the typewriter. This provides for an operative cycle wherein any shift or spacing or carriage return operations are arranged to occur after a character has been printed and the character circuit has been automatically reopened at the switch 6| in the described manner, it being recalled that the code wheels 80 and the switch control assemblies I51 and I58 of the control unit 88 are mechanically actuated by the return movements of the freed and previously advanced pawls I39 and ISI and IE2 respectively.

In printing a coded message with the present apparatus, a character is printed whenever a space occurs in the original message, and means are provided for utilizing one of the keyboard characters for the purpose. The character chosen would preferably, though not necessarily, be one which occurs less often in written matter; in the present instance the letter Z has been chosen to represent a space in the original message. Accordingly, and as shown in Figure 28, the contact 91 for the space key 40 is connected by a wire 252 to the wire I03 from the contact 51 for the Z key, and the connection between the reversing switch contacts I06 of the reversing switch I04 which has the wire I08 connected thereto is omitted. A wire 253 connects the wire I03 which leads from the switch contact I06 for engaging the input terminal I05 of the Z switch during coding with the switch arm I30 on the plate 33, and a wire 254 connects the contact I28 on the member Ht with the wire 249 from the contact I 21 at the other end of the member.

Having the switch I28I3Il open during coding, the letter Z is arrangad to be coded through the code wheel assembly It in the same manner as any other keyboard character to cause ,a. printing or the coded character of the letter Z whether the Z key or the spacing key 40 is depressed. If, however, the member I It is shifted to decode position, the switch I28-I30 is closed, theswitch Iii-429 is opened, the Z input terminal I05 engages a reverse contact I09, and the corresponding output terminal H2 engages the unconnected reversing terminal I06 whereby no connection is provided for the wire III from the terminal II 2. Under the latter conditions, if a key 36 for a code character which is the code for Zor a space is depressed, a closed circuit is created to include a wire I I19, the code wheel assembly I1, the wire I08 which leads to the Z contact I06, the wire 253 to the switch contact I30 which engages the contact I28, the wire 25d; and the wire 249 to the solenoid 233--s of the printing machine. In this manner, a space is provided in the decoded and printed message whenever a space or the letter Z occurred in the original message, it being important to note that the present device has coded I spaces with the same coding complexity as the characters of the keyboard.

From the foregoing description, taken in connection with the accompanying drawings, the advantages of the cipher mechanism ofmy invention will be readily understood by those skilled in the art to which the invention appertains. While I have described the principles of operation, together with devices which Inow consider to be preferred embodiments thereof, I desire to have it understood that the showing is primarily illustrative, and that such changes may be made, when desired, as fall within the scope of the following claims:

I claim:

1. In a cipher machine, an electric keyboard comprising a plurality of keys, a coding circuit providing in part a set of mutually parallel branch circuits having one branch circuit for each key, normally open switches interposed in the different branch circuits and selectively closable by said keys, a normally open .master switch interposed in an unbranched circuit part and closable by any of said keys, a normally open electromagnetic switch having its solenoid interposed in the unbranched circuit part, an electromagnet operative to eflect an opening of the master switch, and a secondary circuit including the electromagnet and the switch of the electromagnetic switch whereby the closing of the coding circuit is operative to open the master switch therein after a coding operation i completed.

2. In cryptographic apparatus, a plurality of keys for selective actuation, means providing an electric circuit including in part a set of mutually parallel branch circuits, individual switches interposed in the different branch circuits and closable by said keys, an electromagnetic printing mechanism operative in each branch circuit, a rotatively adjustable code-changing wheel providing closed portions of all of the branch circuits between the switches and printing mechanism for .tromagnet when the circuit is closed by the actuation of said key.

3. In a code changing means for a cryptographic machine, a member providing two interconnected like sets of electrical contacts which are aligned and equally spaced in their sets in graphic machine, a member providing two intercircles having their centers in a common line, a second member providing two sets of contacts complementary to and normally engaging the contacts of the difierent sets of the first member, means mounting the members for their relative rotative adjustment about said line, and means operative to efiect successive rotative adjustments of one member with respect to the other through half the angular spacing of successive contacts, the contact of the mutually engaged pairs of contact sets being so related that each actuation of the adjustment means is arranged to change the connections of the contacts of but one said pair of sets.

4. In a code changing means for a cryptoconnected like sets of electrical contacts which are aligned and equally spaced in their sets in circles having their centers in a common line, a second member providing two sets of brushes complementary to and normally engaging the contacts of the diiferent sets of the first member, means mounting the members for their relative rotative adjustment about said line, and means operative to effect successive rotative adjustments of one member with respect to the other through their respective lines that they extend for no less than half their center-to-center spacin therein, a second member providing two sets of brushes complementary to and normally engaging the contacts of the difierent sets of the first member,-- means mounting the members for their relative rotative adjustment about said line, and means operative to effect successive rotative adjustments of one member with respect to the other through half the angular center-to-center spacing of successive contacts, the said contact sets being so related to said brushes that an actuation of the adjustment mean is arranged to maintain the engagement of one set of brushes with the same contacts of one contact set while effecting the contact of the other set of brushes netic printing mechanism operative in each said branch circuit, a plurality of mutually adjustable code wheels interposed between the switches and the printing mechanism for jointly providing variable closed portions of all of said circuits, individual electromagnets operative when energized to adjust the setting of said code wheels, individual and normally open control switches for the circuits of said electromagnets, a normally open master switch interposed in an unbranched circuit part and closable by any of said keys, 9. normally open electromagnetic switch having its solenoid interposed in the unbranched circuit part, and an electromagnet controlled by the electromagnetic switch having its solenoid interposed in another branch circuit part and havin its armature dipslaceable in a workin stroke to open said master switch and thereafter effect a selective closing of one or more of said control switches for the wheel-adjusting electromagnets of the code wheels.

' EDWARD H. HEBERN.