US2402082A - Mechanical ciphering system - Google Patents

Description

June 11, 1946. A. H. REIIBER INVENTOR ALBERT H. RE I BER, DECEASED ATTORN EMILY Y. REIBER, EXECUTRIX MECHANICAL CIPHERING SYSTEM I 0r1g1nal Flled July 29, 1943 Patented June 11, 1946 U'NlTED arias TE OFFECE MECHANICAL CIPHERING' SYSTEM Original application July 29, 1943, Serial No.

496,552. Divided and this application December 8, 1943, Serial No. 513,375

9 Claims.

The present invention relates to printing telegraph systems and apparatus and particularly to apparatus for effecting the transmission of secret or confidential telegraph messages.

The present application is a division of application Serial No. 496,552 filed July 29, 1943.

Signalling systems are desirable for naval, military and civil purposes wherein it is required that messages be rendered unintelligible to persons unauthorized to receive them. surreptitious interception of messages may be accomplished, for example, in the case of wire communications by tapping'signal wires, and in radio communication by means of receiving apparatuses tuned to the proper frequencies.

The principal object of the present invention is to provide simple, compact, and reliable facilities in telegraph systems and apparatus for rendering' messages unintelligible to unauthorized persons.

Another object of the invention is to provide a system and apparatus for precluding the un authorized interception of intelligible messages by mechanical operation established in response to the respective control conditions.

A further object of the invention is to provide enciphering and deciphering instrumentalities which are readily adaptable to commercially available printing telegraph apparatus.

In order to encipher messages by the present system'and apparatus, the elements of the code combinations of the original, intelligible message are combined with the elements of code combinations provided by a key tape or other control mechanism. In such arrangement, pposite conditions, that is, with one element of the original code combination marking and with the corresponding element of the key code combination spacing, produce a marking signal. Like conditions, however, with both elements marking or both elements spacing, produce spacing signals. This presumes, of course, that each of the elements of the respective code combinations are related to each other. That is, the No. 1 element of the original code combination is combined with the No. 1 element of the key code combination, and so forth. To take a specific illustration, let it be assumed that it i desired to encipher the character R which in the Baudot code is composed of spacing, marking, spacing, marking, and spacing conditions. Let it be further assumed that the key tape with which the particular enciphering operation is to be performed occupies a position whereat it is conditioned for producing the letter Y combination which in the Baudot code is composed consecutively of marking, spacing, marking, spacing, and marking conditions. Under the assumed conditions, the enciphering operation would result in the production of an all marking or letters combination, since in this particular illustration opposite conditions of all the .related elements of R and Y code combinations are provided. This will be readily apparent from the following chart wherein the letter M indicates a marking condition and the letter S indicates a spacing condition.

Original signalR S M S M S Key signal Y l M S M S M Enciphered'signalletters M M M M M It is understood that both the transmitting and receiving end of a telegraph line will be r ample given above in connection with the enciphering operation will be continued and it will be assumed that a receiving station received the enciphered signal; namely, letters. The Y combination provided by the key tape or other control mechanism at the receiving station can now be combined with the received letters com bination to decipher the enciphered signal to thereby reproduce the original signal R, as clearly shown in the following chart:

tion may be had from the following description taken in conjunction with the accompanying drawing, wherein:

- Fig. 1 is a plan view of the keyboard controlled enciphering device according to the present invention;

Fig. 2 is a sectional view taken on line 2--2 of Fig. 1;

Figs. 3, 4, and 5 are views illustrating the enciphering device in its various operational positions; and

Fig. 6 i a schematic electrical diagram for the transmitter according to the present invention.

In Figs. 1 to 5, inclusive, is shown a transmitter which is keyboard operated and which transmits enciphered signals which are deciphered at the receiver. Briefly, upon the operation of a key lever to transmit a character over the signal line, the signal actually represented by the key lever will not be transmitted, but such signal'wilI e a te e 0 C ed y an 'enciphering device.

The keyboard mechanism comprises a base portion N (Fig. 2) which carries therein a series of key levers l2. As is customary in such keyboards, the key levers |2 are pivotally mounted at the rear of the apparatus or base and are spring urged into their horizontal positions so that, when they are depressed, theywill shift a series of five selector bars I3. Th keyboard shown herein is of the type disclosed in U. S. Patent No. 1,595,472, issued August 10, 1926, to H. L.

Krum. As a key lever I2 is depressed it acts upon the saw-toothed cam lugs I4 to shift the code bars l3 rightwardly or leftwardly, the code bars being slidably mounted on bearings I 5. 7

Each of the code bars I3 is provided with a pair of studs I6, between which operates the depending arm of. lever I'l pivotally mounted on a pivot shaft I8 journaled in the bracket 9. The upper or vertically extending arm of lever I1 is provided with a laterally directed extremity 2|. Also mounted on the pivot shaft I 8 and individual 'toeach lever I! is a, pair of vertically extending arms 22 and 23 between which the laterally extending extremity 2| f lever I1. cooperates. Associated with each of the pairs of levers 22 and 23 is a bell crank lever 24 which is pivoted on the pivot shaft I8. Thus, for each codebar I3 there is provided an assemblage of levers I1, 22, 23, and 24. The levers 22 and 23 are normally urged toward each other by a common spring 25. The bell crank 24 is provided with a vertically extending arm having alaterally directed extremity 26 which cooperates with the confronting edges of the arms 22 and 23. Lever 24 is normally biased in a counterclockwise direction about the pivot shaft I8 by an individual spring 21. Theextremities of the horizontal arms of the bell crank levers 24 cooperate with plungers 28 of a series of solenoids 3| to 35, inclusive, of which there are five in number corresponding to the five bell crank levers 24. The solenoids 3| to 35, inclusive, are suitably mounted on mounting plates carried on posts 36 secured to the base Upstops 3'! are provided for each of the solenoids to govern the movement of the plungers 28.

Each of the arms22 and 23 is provided near its upper extremity with a shoulder 38. Cooperating .with the pair of shoulders 38 is the laterally directed extremity 39 of a series of gooseneck shaped contact levers 4| pivotally mounted on a pivot shaft 42 carried in the bracket |9. Each of the levers 4| is provided with a cam follower projection 43 on its horizontal arm which coacts with a transmitting cam 44 of which there are five in number in the present instance. These earns 44 are fixed to the transmitting shaft 45 which has associated therewith a toothed or grab clutch (not shown) which is asingle revolution clutch,

4 as is well known in the art. Each of the cams 44 is provided with a cam notch 46. As disclosed in the afore-mentioned U. S. Patent No. l,595,- 472 the cams 44 are so disposed on the shaft 5 that their cam notches 46 are arrangedin a helical series so that, upon rotation of shaft 45, the levers 4| are operated sequentially. Associated with each of the levers 4| is a contact 41 which is normally open. As described in said patent a sixth cam 48 (Fig. l) is provided, the contact lever 49 of which is so related with the cam that its contact corresponding to contact 41 is normally closed in the stop position of the cam assembly, thus maintaining a marking condition on the signal line to which the contacts 41 are connected. Said cam 48 is known as the start-stop cam.

Also fixed to the cam shaft 45 is a locking bail cam 5|. Cooperating with the periphery of the cam 5| is a follower roller 52 carried on an arm of the locking bail 53 which is pivoted at 54 to the'frame I9. The bail 53 cooperates with the pointed extremities of the arms 22 and 23 to lock them in one or the other of their selected positions, as more clearly shown in Figs. 2, 3, 4, and 5.

In the operation of the transmitting mechanism shown in Figs. 1 to 5, inclusive, it is assumed that a key lever has been operated, which has moved the code bar |3 to its rightward position, as shown in Fig. 2, whereby the lever I1 is rotated to its counterclockwise position, thus causing its lateral projection 2| to actuate the arm 22 to its leftward or counterclockwise position thereby bringing its shoulder 38 out of the path of the lateral portion 39 of the contact lever 4|. Thus, it is observed that the shoulder 38 of arm 22 does not, during this condition of operation, block the movement of' the' contact lever 4| to close its contact 41. However, this movement of the contact lever 4| may or may not 7 be blocked by the companion shoulder 38 of the arm 23. In Fig. 2 the shoulder 38 of the arm 23 is shown out of the path of the portion 39 whereby the contact lever 4| is free to close its contact 41 when the cam notch 46 passes over the follower 43.

In the condition of operation in Fig. 2, the bell crank 24 of the enciphering device is shown in its clockwise position with its lateral portion 26 acting to urge the arm 23 to its clockwise position against the action of spring 25 to bring the shoulder 38 thereon out of operative relation or engagement with the lateral portion 39 of the contact lever 4|. Thus, it is observed that the signal impulse transmitted over the line through the contact 47 is of marking nature.

In the condition of operation shown in Fig. 3, the code bar I3 is still shown in its rightward position, thus holding the arm 22 out of the path of the projection 39 of the lever 4|. However, the enciphering solenoid 35 is shown in its deenergized condition with the plunger 28 released to permit the spring 21 to rotate its associated lever 24 counterclockwise to permit the spring 25 to bring the shoulder 38 of the arm 23 over the projection 39 .of the lever 4|, thus blocking the counterclockwise rotation of the lever 4| and precluding the closure of the associated contact 41.

In Fig. 4, the code bar I3 is shown in itsleftward position having been operated thereto by a key lever I2. In response to this movement of the code bar I3 its associated lever has been actuated clockwise to the position shown in Fig. 4 whereat the lateral projection 2| has moved the arm 23 to its rightward or clockwise position to bring the shoulder 33 thereon again out of the path of the projection 39 of the lever 4|. The lever 22% is still shown in its counterclockwise position due to the fact that the enciphering solenoid is still de-energized. The spring 21 causes lever 24 to follow plunger 28 to bring the lateral portion 2% against the arm 22 thus urging the arm 22 to its counterclockwise position, bringing the shoulder 38 thereon out of the path of the projection 38 of the lever 4!. In this condition the gooseneck lever BI is free to respond to the notch 46 in the cam M to efiect the closing of its associated contact Ill.

In Fig. 5 the code bar i3 is still shown in its leftward position thus holding the arm ll in its clockwise position so that lever arm 23 is held in its clockwise position to maintain the shoulder 38 thereon out of the path of the projection 39 of the lever M. In Fig. 5 the enciphering solenoid is shown in its energized condition whereby the lever 23 is held against the back-stop against the action of the spring 21. In this position the lateral portion 26 of lever 24 assumes its clockwise position to permit the shoulder 38 of lever 22 to be positioned above the projection 39 of the lever ti thus blocking the contact lever 4! against movement so that the contact 41 associated therewith remains open.

Electrical circuit In Fig. 6 is shown an electrical circuit embracing the transmitter of the present invention. In the rectangle 6i is shown the transmitting contacts til associated with the rotary cam distributor, and the contacts 52 which are controlled by a key tape 63 or other control mechanism. It is noted that each of the contacts 62 is connected to a solenoid 3i to 35, and that the contacts 41 are included in a circuit extending from ground, through battery, then through the contacts 41 sequentially, then over the line 65 to the receiving station. The closure of contacts ll permutatively is the resultant of the setting of code bars l3, by key levers i2, and the closure of contacts 62 by the key tape or other control mechanism.

Although a specific embodiment of the invention has been disclosed, it is understood that the invention is not to be restricted to the structure herein described but is to be given an interpretation determined by the scope of the appended claims.

What is claimed is:

1. In a secret code transmitter, a series of elements moved permutably according to a signal of plain English, a corresponding series of members set in permuted position according to an enciphering code, a plurality of pairs of members controlled jointly by said series of elements and said series of members, and means including a group of contact controlling levers to transmit an enciphered signal controlled by the mechanical interaction of said levers and said pairs of members.

2. In combination, key controlled means, tape controlled means, cam controlled transmitting means, and a pair of blocking instrumentalities controlled jointly by said key controlled means and said tape controlled means for controlling it said transmitting means to alter the signal code combination initiated by said key controlled means.

3. In combination, key controlled means, tape controlled means, transmitting means, and a pair of instrumentalities controlled by said key controlled means and said tape controlled means for controlling said transmitting means to alter the signal initiated by said key controlled means.

4. In combination, key operated means comprising a plurality of keys, code bars controlled by said keys, and an element controlled by each code bar, tape controlled means, a pair of instrumentalities associated with each element and controlled by said tape controlled means, and said element, and transmitting means effective to transmit code signals as determined by the joint action of said key operated means and said tape controlled means.

5. In a secret code transmitter, a series of elements moved permutably according to a signal of plain English, a series of elements set in permuted position according to an enciphering code, a plurality of pairs of instrumentalities, one pair associated dually with each Of said first and said second series of elements, and means to transmit an enciphered signal controlled by the mechanical interaction of said two series of elements and said pairs of instrumentalities.

6. In a secret code transmitter, key operated means comprising a plurality of keys, code bars controlled by said keys, a series of elements moved permutably according to the setting of said code bars, tape controlled means, a series of elements set in permuted position according to the operation of said tape controlled means, a plurality of pairs of instrumentalities, one pair associated dually with each of said first and said second series of elements, and means to transmit a signal controlled by the mechanical interaction of said two series of elements and said pairs of instrumentalities.

7. In a transmitter, a plurality of keys, a set of code bars controlled by said keys, a series of members controlled by said code bars, a plurality of pairs of elements, one pair associated with each member, means for variously controlling said pairs of elements in addition to a predetermined control exercised upon said pairs of elements by said members, cam operated members controlled by said pairs of elements, and a plurality of in strumentalities selectively operated by said members.

8. In combination, transmitting means comprising a plurality of key controlled levers, a series of code bars for governing said levers in a predetermined manner for each key operation,

Images