SPECIFICATIONImprovements in numerical and alphanumerical rational keyboards for typewriters, teleprinters and the likeRATIONAL KEYBOARDS:This invention relates to a new arrangement of the numerical keys in an alphanumerical keyboard for typewriter, teleprinter, and more generally all machines or apparatus for communication or treatment of written information, having a keyboard for typewriting with two hands, the ten keys being affected to the ten figures 0 to 9 and each one destined to be stroked by a different finger, being arranged in such a manner that the typist can make use of the digital mechanisms which he acquired when as a child he counted on his fingers. Due to the reliability of this mechanism, typing figures without having to look at one's keybord becomes easy and not tiring.
DESCRIPTION OF THE PRIOR ART:Most typewriter keyboard numerical keys appear on a single row and the figures aranged in increasing order from left to right starting with the figure 1 and ending with 9 and 0. While this arrangement is simple and seems rational, experience shows that very few typists can type numbers without having to look at the engraved keys on the keyboard, a thing which creates fatigue. Other keyboards offer different arrangements, like having even and odd figures on different sides of the keyboard, but in all cases typing figures remained tiring due to the fact that one had to look at the keyboard to type them.
LIST OF FIGURE DRAWINGS:Figure 1 shows the arrangement of the characters of the rational French keyboard as it appears in the documentation pamphlet of the French organization for standardization AFNOR.
Figure 2 shows another arrangement of figures on any alphanumerical keyboard.
Figures 3 to 1 2 show several keyboards which are solely numerical.
Fig. 13, 13a, 13b, 13c, 13d, 13e, show different improvements, some known, others new, the adjunction of which can be beneficial to the rational keyboards.
Figure 14 shows, as an example, an international keyboard calculated for an imaginary language which would include 2/3 English and 1/9 of each of three languages -- French, German and Spanish.
As this keyboard could not include all accented letters of each language, none of them appear. It is to be remarked that in order to proceed to its determination, all statistical data was at hand for calculation.
But to few tests were achieved and one had solely to depend on the results of the experimentation accomplished in French with the rational French keyboard, and apply them by analogy.
Figures 1 5 to 1 8 show this same keyboard as adapted to the English, French, German and Spanish languages.
Figures 19, and 20 to 23 show a second series of examples of international keyboards adapted to the four languages mentioned.
Figure 24 shows a 'spread out' keyboard (for children) having no shift lever and including 56 keys on 5 rows instead of 4.
The numbers appearing under the keys of figure 1 indicate their positions which are those of the eventual corresponding levers. They are mentioned all along the description. The numbers appearing under the keys of figure 24 only apply to that figure.
SYMBOLS:In all these figures the same symbols concern the same elements. Such is the case for I, II, ill, IV, which designate from top to bottom, the four rows of keys, 100 designates the normal keys, 100' a key called "dead" key which doesn't activate the space bar, 101 are the tongue-keys of row IV, 102 the space bar, 103 the tongue-keys of row lil, 104 concerns new shift levers to be operated by the thumbs, 1 05 is a separation between the left and right sections of the keyboard.
The numeric figures 1 to 5 followed by the letter L or R is the numerotation of the fingers left or right, 1 for the thumbs, 2 for the index, 3 for the middle fingers, 4 for the ring fingers, and 5 for the little fingers.
The lines between the columns of keys on figure 1 delimitate the zones of action of each finger.
RESEARCH:When analysing the stroke mistakes in numbers made by French students in French schools with the traditional keyboard ('azerty'), a tenacious digital mechanism was tracked down which was completely forgotten : in France, most children count on their fingers starting with 1 on their thumb generally that of the right hand, then, 2 with their index, etc. The mechanism which has resulted was confirmed by the various surveys made in several schools with students of all ages. As an example, one of them - the IREO of Buxieres (Haute-Marne), having tested 45 students 16 to 19 years old has stated what follows : "26 students used their right hands, 19 their left. All started to count the number 1 on their thumbs".
It is advantageous to make use of this mechanism. Tests, in effect, have shown that students summarily formed to type numbers on the new keyboard made much less stroke mistakes, went faster and were less tired, than those typing on the traditional keyboard, which they had used for a much longer period of time. Furthermore, they did not have to look at their keyboard.
This demonstrates, how much the mechanisms acquired at a young age are reliable. It is however to be noted that this gratuitous mechanism only proves to be efficacious if the numeric figures 1 and 6 are struck by the thumbs and not by the index in extension. One cannot therefore have a single row of numeric keys because the thumb is too distant from the other fingers.
TONGUE-KEYS:The right and left parts of the new keyboards forming between them an inverted V, it became possible to implant two tongue-keys in the available space in the middle of the keyboard in a place where they can easily be struck by the thumbs when the other fingers are positioned on the numeric row 1. As a result, the arrangement of the numerical keys represented at figure 1, has been established.
What preceeds is operative in France, in countries of French language and a few other countries. It is to be noted that in these countries, the teachers, in general, do not allow their pupils to count on their fingers - a thing which has for effect to prompt them into doing it. Without any guidance on the matter and for an unknown reason, all the children start counting 1 on their thumb - generally that of the right hand. It is apparently innate.
In other countries, the teachers, on the contrary, teach their pupils to use their fingers to count.
However, for a reason also unknown, they make them start with their right index for the number 1 and the thumb or the fist for the number 5. In order that the persons who were so conditionned are able to use these mechanisms, it became necessary to modify the arrangement of the numerical keys accordingly, as it appears at figure 2.
Figure 3 shows a keyboard which is only numerical, to be operated with two hands, having the same arrangement of keys of the alphanumerical keyboard represented on figure 1. Following a row preferably curved to adapt to the topology of the hand, appear for the right hand the keys of the numeric figures 2 to 5, arranged progressively from left to right and destined to be struck 2 by the index, 3 by the middle finger, 4 by the ring finger, 5 by the little finger ; and for the left hand, the keys of the numbers 7, 8, 9 and 0 arranged progressively from right to left, and destined to be struck, 7 by the index, 8 by the middle finger, 9 by the ring finger and 0 by the little finger. The numbers 1 and 6 are affected respectively to the right and left tongue-keys which are positionned under the rows of the other numbers and destined to be stroked by the right and left thumbs.
Figures 4 to 7 show numerical keyboards having two rows preferably curved of keys and destined to be operated with one hand, the keyboards of figures 4 and 5 with the right hand and those of figures 6 and 7 with the left hand. On figure 4 the numbers 2 3 4 5 belong to the top row and on figure 5, they are on the bottom row. On figure 6 the numbers 2 3 4 5 are on the top row and on figure 7 on the bottom row. The numbers 1 and 6 are affected to tongue-keys positioned below the rows of keys affected to the other numbers and are destined to be stroked by the thumbs. Of the two tonnue-keys, that which is affected to the number 1 is the closest to the key affected to the number 2.
In all the figures 4 to 7, the numbers 2 and 7 are destined to be stroked by the index, 3 and 8 by the middle finger, the numbers 4 and 9 by the ring finger, the numbers 5 and 0 by the little finger, the numbers 1 and 6 by the thumb.
Figure 8 shows another numerical keyboard to be operated with two hands, the numbers having the same arrangement represented at the alphanumerical keyboard of figure 2. On the top row for the right hand are the keys of the numbers 1 to 4, arranged progressively from left to right and destined to be struck, 1 by the index, 2 by the middle finger, 3 by the ring finger and 4 by the little finger; and the numbers 6 to 9 are arranged progressively from right to left and destined to be struck by the left hand, 6 by the index, 7 by the middle finger, 8 by the ring finger and 9 by the little finger. The numbers 0 and 5 are affected respectively to the left and right tongue-keys destined to be struck by the left and right thumbs.
Figures 9 to 12 show numerical keyboards with two rows destined to be operated with one hand, the keyboards of figures 9 and 10 with the right hand and those of figures 11 and 12 with the left hand.
On figure 9 the numbers 1 2 3 4 belong to the top row. On figure 10 they are on the bottom row. On figure 11 the numbers 1 2 3 4 are on the top row and on figure 12 on the bottom row. The numbers 0 and 5 are affected to two tongue-keys destined to be struck by the thumbs. Of the two tongue-keys, that which is affected to the number 5 is the closest to the key affected to the number 1. In all the figures 9 to 12, the numbers 1 and 6 are destined to be stroked by the index, the numbers 2 and 7 by the middle finger, the numbers 3 and 8 by the ring finger, the numbers 4 and 9 by the little finger, the numbers 0 and 5 by the thumb.
Figure 13 shows in plan an alphanumerical keyboard having improvements some known some new, like the shift levers 104 and the partition 105.
Figures 1 3a to 1 3d are elevations connected to figure 13 following the horizontal a P y 8 and figure 1 3e is an elevation following the line E.
On all these figures are assembled the various improvements -- known or new which can contribute to render rational keyboards more effective.
LOWERED KEYS AND PROTUBERANCES:On figures 1 3a and 1 3b it can be seen that the keys 11 31 9 and 33 are lowered and that they bear protuberances 106 - one protuberance in the center of the key for the numerical keys 11 and 31 and two on the bottom of the keys 9 and 33 of row Ill of the letters. It is advantageous to lower also the keys 10 and 32 which are in the same columns. These lowered keys and the protuberances implanted in four of them serve as guiding marks to the middle fingers which can securely feel their right positions, a thing which is quite impossible when the keys are placed all at the same height and possess no distinctive difference to the feel, as in most keyboards today. As a result, the typist may strike inadvertently a series of false strokes.
SURELEVATED KEYS:Figures 13, 1 3a and 1 3b show keys which are surelevated in the positions 1 7 21 25 44 and 45. It is to be noted that the keys in positions 18 24 and 43 (see figure 13) are also surelevated. This has for effect to secure additional guiding marks to feel the limits of the keyboard in order to avoid false strokes.
PERPENDICULAR KEYS:Figure 13c which is an elevation of zone y of figure 13, and figure 1 3e which is an elevation following the line E, show on row IV several keys 107 like those in positions 8, 34, 42, which are placed at a higher level and sensibly perpendicularily to the others. This has for effect to facilitate their striking which can be done without having to displace the hand when the fingers are on row Ill.
SHIFT LEVERS:On figures 1 3 and 13d, one can seen in plan and elevation the shift levers 104 which are destined to be operated by the thumbs by traction from right to left for the left shift lever and from left to right for the shift lever of the right. These levers advantageously replace the shift keys which are hard to depress with the little fingers, especially on a manual typewriter. The thumbs being stronger than the little fingers, less effort is necessary to shift and, also, this can be done without having to displace the hand which can remain in the best position to continue typing.
TONGUE-KEYS OF ROW IV:Concerning the tongue-keys 101 reserved for the thumbs, it has been found out that the ones closest to the palm of the hand (in positions 1 6 and 26) should preferably be shorter than the others (in positions 1 9 and 23) and also that they be placed lower. In this manner, the thumbs can reach them separately without any difficulty or risk of striking them together.
TONGUE-KEYS OF ROW Ill:The tongue-keys 103, in positions 20 and 22 are destined to be struck by the thumbs when the other fingers are on the numerical keys of row 1. They are stroked by the index fingers when typing letters, at which time the fingers are resting on row Ill. For mnemonic reasons, the two open and close parenthesis have been assigned to these two tongue-keys, open to the left one, close to the right one.
It is to be remarked that the implantation of so many tongue-keys has been found possible after extensive tests have proven that the thumbs could well support this load.
SEPARATION:A separation 105 between left and right tongue-keys serve as a guide mark to the thumbs.
KEYS 21 AND 44 (figures 1 and 13):On the numerical row I the two keys 21 and 44 have been implanted to be affected to the decimal point or coma and percent sign (%) destined to be struck by the right hand index and little finger, when positioned on row I to strike the numeric figures. These two keys are more distant from the others purposely in order to avoid false strokes which could occur by displacement of the hand over the keys.
ALPHABETIC SECTION OF THE KEYBOARDS:Besides that of the numerical keys, the arrangement of the letters and frequent signs has been the object of a scientific determination. So, the alternation of the hands being considered as the most imperative of the criteria, a matrix of the sums of digraph frequencies and their inverses has been established for each language including the imaginary international one.
MATRIX OF THE SUMS OF DIGRAPH FREQUENCIES (f,i+fP} On table 1 on the next page, the matrix shown applies to the French language. on abscissa as well as on ordinate frequent characters are classified by left hand and right hand. Totals have been made vertically. One can see that the totals of frequencies in the portion tp-left are those of the digraphs struck by the left hand, those in the portion bottom-right, by the right hand, and the alternations of the hands appear on the portions top-right and bottom-left, the totals of which are, in fact, equal.One can see that if, for any character, the total of the frequencies in the column situated in a portion including the alternations is superior to that in the part of the same column situated in the other portion, the alterations are supernumerary and the character is placed on the best side to favor alternation.
Incidentally, one can verify that the percentage of alternation derived from the matrix is very close to that calculated on computer.
At the bottom of the matrix appear the differences, positive if the frequencies of alternation are the largest and negative otherwise. The informations derived from the matrix are most pertinent. From them one could realize, for instance, the necessity of affecting to the left hand the period and the coma, and to the right hand, the letter X, though its frequency is small (427 x 10-5). One can also see that the positive totals are plainly superior to the negative ones, most of the latter being negligeables and could not, in fact be redressed by changing the characters of side, because there would not be enough characters left to the left hand.
IMPROVEMENTS RESULTING FROM EXPERIMENTATION:The methodology for determining a rational keyboard in function of a given language has been explained by the inventor in the description of the French patent No 7623323 (1976) and has engendered the rational keyboards thereby drawn. Since then, some improvements obtained often thanks to experimentation, have been mentioned in the certificate of addition No 79 01065 of July 1 7, 1979, of which the priority is claimed under the Paris convention. These improvements -- which bring the new keyboard closer to the theoretical optimum -- are explained below TABLE N 1
x iH L > N i U H IC .. B Q * D, < J. hJ.. .? e T V X ~ ; 'I . w qyo . i'7'; 1A3{:jLA'.}'l & ! . ' . .r.!}34.a, 3o 70 lT9..;:W I . tr' 34, ( , *7 It' 113 9 fl a.s7 C tJ ito r.
0 0 Sft,cI,LL,3 - .- 0 . ot o' 0 t. p a , a do 4. d5 0 7 .bti" 9 ,t' 3,a k7 - At ''n:k li ,I . e I t, t 5 + < ,; o ,' Jj & :" 7r 13r, 10 o 7 ç e ^ 13 Jf34 i.A.. *9',ar *Jt 9 s! 9 0 t7o;3 3 fl 0 ,=, t 6 | t s A. .?J.'. ts.lfoN.i'.ctfirt. 4 s,'s,;,; ij,qc, & '?..".')J 4 v (I, "azS 17 I'S to' '0 as BA it a a' A i IL C S 0 , 0.; $fflLi .: & . ;. - I .. - . .- . --- -- :=I;.LS.L- d a,, o -s ~ S ~' "I i' tt '9 a I -- ~ '1Ft 0 0 0 .3. .0. C 2 .3 ' 0 0 te w t $iqtb ; ' i?Ot.' u -:a; :-- ;io;:-;: -- :i̇. a;; W ;.' :z; jf))7r1;f-- ,AI t ! ", ;- s 'e a' E D, * F; ,kl . jq 7 a , s 3'6, '.t,7 C 14 tj.-1 3. ~~ ~~ 10 AS. o..rJ 9 AjiatI 'N 4. A It J 'at' Si Q t b," tt 4~ .le !fl 10 .IIt7a j{jTf ?ffiW)' - - -- '--. ....'-.. .- Qoa'.Nitla7?3.3 u S eil k, n 1 % ' ;o ".?rJ!; "'. f"tcfi.;ca el se , q B 11:0 0 A 2a,o '41 3 ~ 0 to Li a .t!..sr.s..!d 3.. -o o irS d2 13 o' 0 - | tl;30 IaT}2?.o.ilD i > ,e~.i 4Slw e bea .~ !} 7 - - a . . s i~lel b o; o w - ol * 1, ni; x ' 9 I - A . t a as. 0 0 -O 0 0, a 0'' ;- j( & i2'LI' ! 0 'j S S, r Itto X +: , e; ,,0t a F to E b ^ i 0, - 3Lia 0 lA,,tI'i7 AS, 210 ll 11' 0 ,Sa a - " ? ' - -a- 0,4 - - a AS! 5' 13 a a 0 ( J + fi s | C at i & . a,ffia'3' .o'I .-I , ,,a,., e ~ 3'OgO,, sr, . .1.0.. ea . ' 7 ll;l'Atq .. 2 , a i' t'1 jq jt q (t it - i, a I a , 31 .9 iii 11115 , - atla 1,5 lJ .31) a r itt . a r c M 1a tì;l7 S?,1o,' 147 7 1! 1 0 t7 'l'I ASr taaer a" l5 10 0 a a 'S N l71L a 3tt1i1L ii' tt0Ii1ts ,lj IS i'ffl 4 o ' .2; tie 0 'Iaiap e ol,ftl,, " ! Is t.o'.Ial ; Ie z'' i7?1q7 all a 11 a i .
P i 5;; , a S331 iou * e e; | l a -t 3 i ,o, - aa a | i e . "'l"' ?'g$ s o ts ij, a q IS ILL is lit a a I,. . a , ,, a. Sb N a aL.1,sq a 0 a I (J1 f'7 153 ittal tf"tla Al ii "! I 02 ea ; t::Ir'.-h'?1a7'I s all p ef e.x > o. t lee 11 a e t S 7S4 i 1Al1 10 lSt i I . 19 i 3 I Ila 43 Al' too .a ..J) jl ,r I na it .V9.' sI. .54 aba ~~ + a a T lila 4 2ae' 717 47 a7a 1 e! Is, as. a ! I 0: > 75 . Sba t',, :..ca.a 10, 4fl 7,0 A ILeeL I ,- Ale u J0 V btl a 55 iqo . 12 . 0 0 0 a 10! .0 t 0 a i: 'a i5' 1, 1 a a X 0 0 a a z e imt iv Ia o n rz o t ;;- t; o ff ~. p 1101 . a i''t, I t , a " | tit " :.;cN.. :- | ~. a I' a 0,, a 5 42, t.ki 17 3i'oiio a JAl'i,S,B..t O,; o. e 4.|at s' it.tF ii 13311' . 117 Xt ffi' 11aiq sI'it' .o4 | oie!-; ' ,10hoK ; ki' o?.{rs Cial,lI 1d, t .I ; C ~ 7n ; ,; ≈ ~ N' w o' Ooo et; ; i o 3 15111 > : , 'Iz, 4?i'a.'i w 10--i 5 ioiP I 'o Sl25 s7'j"ssis:.cJ?s.'rjs"'s' s",7, i, & 3, io.I.:c?!s)i, o,* :.Y.6 & '!c' 5t' - Jot?' ..'!.
Y ~;* o. < tt,vt; etj Ej gi i ie! jolootolSax o wxoe 1- ~ ~ o "!9b- X el aioio!wiol a- 9 4;; 7 o - a e v o ~qo h X jO-s,, ; a ;t 8 e. v > x ,h e Z s ^ o Q t * b > ~ b o ~ O e O o ~ .7 o . h < . o l ≈ s ! 4 i 4t 4 ~{ 9 Ft t0 4 v t i g F < % t > e d 4 o w t s 6 w o, t t i e > t t t; ir tz F a- t s ii ,a00 4 ;!Wo1 ~ 94F ,,~ rt-6nt t % ~ Sd o o . - 9 o o o | 5 o * , o w e ' e O o o F ;4 a < , o ;tW o a ~ 't fie; t " *- ~ e t > r r X 5 > oB O u < Jd Si < *i ^ O O > 1=, X 3 Z . ! *, , ; ^ u * R R o- . J S 2 e a,: vt F , > x - ;g, s + TONGUE-KEYS FOR THE LETTERS C AND G:In row IV two tongue-keys have been assigned to the letters C and G which, when assigned to any others keys were engendering adjacencies like that of CS (frequency 100 x 10-5) and the difficult strokes GN (frequency 256) between the ring finger and the little finger. On the other hand, there is a negligeable adjacence between C and G (frequency 3) (the word 'adjacence' means the strokes by the same finger of two adjacent keys).
It remained to determine what tongue-key to choose for either letter C or G. The stroke for either tongue-key being practically as easy, the decision has been based on another criterium : avoid that the typist, striking a tongue-key with the index instead of the thumb, suffers the effect of adjacences or jumps. This consideration has engendered the implantation of the letter C to the tongue-key 23 the most distant to the index thereby avoiding that by an erroneous use of the keyboard the adjacences CL and CT (frequences 11 5 + 280 = 395 x 10-5) occur.
KEYS OF UNFREQUENT CHARACTERS:The arrangement on the left hand of the unfrequent letters in French K W Z which frequencies are negligeable (74, 59, 69 x 10~5) was guided by the considerable frequency in English of the letter W (fr.
1804) and also to avoid a big step for WH (fr. 383). Without harm to the efficiency of the French rational keyboard, the inventor has therefore chosen to facilitate also the typing in English - the most widespread language in the World ---- by placing W in the good position 10 on row II.
RATIONAL FRENCH KEYBOARD:The French rational keyboard represented on figure 1 results from all the considerations hereinbefore mentioned: - the arrangement of row II is from left to right H Y W E - (dash), destined to be struck by the left hand, H by the little finger, Y by the ring finger, W by the middle finger, É and the dash by the index; and M D' (apostrophe) V P (accent circonflexe) destined to be struck by the right hand, M and D by the index, the apostrophe by the middle finger, V by the ring finger, P and the 'accent circonflexe' by the little finger.
- the arrangement of the row IV is from left to right Z : (colon) destined to be stroked by the left, hand, Z by the ring finger, K by the middle finger and the colon by the index ; and F Q X and J, destined to be stroked by the right hand, F by the index, 0 by the middle finger, X by the ring finger and J by the little finger.
- the arrangement of the row I includes, in addition to the traditional signs, the accentuated letters 'è', 'à', destined to be stroked by the left hand, the 'è' by the middle finger, the 'à' by the index, and the letters 'c' and 'ù' destined to be stroked by the right hand 'c' by the middle finger and 'ù' by the little finger: - to the thumbs are affected six tongue-keys : in row IV left hand from left to right, the comma and the period, and in the right hand, from left to right, the letters C and G and on row III, the numbers 1 on the right and 6 on the left, with the parenthesis open on the left and close on the right.
RATIONAL INTERNATIONAL KEYBOARDS:The international keyboards represented on figures 14 to 23 are optimised for an imaginary language which would comprise 2/3 English and 1/9 of each of three languages, -- French, German, and Spanish. These proportions, however, have been chosen arbitrarily.
The keyboards of figures 14 to 1 8 include - on row III the letters U I E A 0 destined to be stroked by the left hand, U by the little finger, I by the ring finger, E by the middle finger and the letters A and 0 by the index ; and the letters N H T R S B, destined to be stroked by the right hand, N and H by the index, T by the middle finger, R by the ring finger and S and B by the little finger, - on row II, the characters K Y' (apostrophe) and Z, destined to be stroked by the left hand, K by the little finger, Y by the ring finger, the apostrophe by the middle finger and Z by the index ; and the letters F P M L G, destined to be stroked by the right hand, F and P by the index, M by the middle finger,L by the ring finger and G by the little finger, - on row IV the signs -- (dash) and : (colon) destined to be stroked by the left hand, the dash by the middle finger, and the colon by the index ; and the letters J O W V X, destined to be stroked by the right hand, J by the index, Q by the middle finger, W by the ring finger, V and X by the little finger.
- the six tongue-keys are affected to the same signs as was the case for the rational French keyboard except for those destined to be struck by the right thumb, which are affected to the letters D, for the tongue-key most central, and C for the other.
The international keyboards of figures 1 9 to 23 comprise: - - on row III the letters U I E A 0, destined to be stroked with the left hand, U by the little finger, I by the ring finger, E by the middle finger, A and 0 by the index ; and D T R S N B, destined to be stroked by the right hand, D and T by the index, R by the middle finger, S by the ring finger and N and B by the little finger, -. on row 11 the characters H Y' (apostrophe), destined to be stroked by the left hand, H by the little finger, Y by the ring finger, the apostrophe by the middle finger ; and W M L F P, destined to be stroked by the right hand, Wand M by the index, L by the middle finger, F by the ring finger and P by the little finger, - on row IV the signs -- (dash) and : (colon), destined to be struck by the left hand, the dash by the middle finger and the colon by the index ; and the letters K J V Q Z, destined to be struck by the right hand, K by the index, J by the middle finger, V by the ring finger, Q and Z by the little finger, - on row I, at the center, the letter X, to be stroked by the index of the right hand, - the tongue-keys destined to be stroked by the thumbs are the same as those for the rationalFrench keyboard represented at figure 1.
GENERALITIES:The international keyboards of figures 14 and 1 9, though they are different, should both be very close to the theoretical optimum keyboard. To find out which is the best, would require comparative tests of a very large amplitude. However, the inventor, basing himself on his acquired experience in the field applied to the rational French keyboard, has suggested as probable that for the French language, the keyboard of figure 21 has a better chance of being letter H, being on the left hand. it became possible to place the letter R which enters into a large number of digraphs on the right hand, to the middle finger, a much stronger finger then the ring finger where it is on the other international keyboard of figure 16.
The great disadvantage of both international keyboards adapted to the French language lies in the considerable number of adjacences between the letter E and the apostrophe (frequency 94 in international but 350 x 10-5 in French). It is the constant repetition of the same load which creates fatigue.
It is to be remarked that on figures 1 5 and 20 position 14, the article THE appears, the most frequent work in English (frequency 6937 x 10-5). A contraction of the three letters is suggested to be typed in one stroke.
The keyboard of figure 24, differently to the preceding keyboards includes 56 keys arranged on five rows. Derived from the rational French keyboard of figure 1, it is spread out as it has no shift lever and each key corresponds to only one character. The numerical top row includes the numeric figures except 1 and 6 which appear on the tongue-keys destined to be struck by the thumbs. On this keyboard appear three 'dead keys' - which do not automatically advance the carriage -- on positions 54 for the 'accent circonflexe', 52 for the diaeresis and 26 for a line destined to underline any letter which normally should appear in capital.The inventor has composed this simplified keyboard for children of scholastic age, in order that it can be used as a didactic instrument speciaily necessary in connection with the new audio-dactylo-visual method which has proved to be so effective in teaching various subjects.
IMPROVEMENTS:All the keyboard improvements explained in this invention, allow, in comparison with the traditional keyboards in use today: - a stroke of letters, signs and numbers more comfortable engendering less fatigue, - a reduction of the number of false strokes,- higher cadences of strokes and increased resulting speed of accomplishment of the work done, - an easier formation of the typists.
TABLES No 2 to 5 : The four tables No 2 to 5 appearing on the following pages show the performing statistical results for the French language, of the traditional 'azerty' French keyboard, theFrench rational keyboard of figure 1 and the two 'international' keyboards adapted to the French language shown at figures 16 and 21.
TABLE 2PERFORMING STATISTICAL RESULTS FOR THE FRENCH LANGUAGE OF THE 'AZERTY' KEYBOARD
LOADS (relative frequencies for 100.000 characters) 10739 8398 22087 17551 15697 8021 10501 63525L 4L 3L 2L 2R 3R 4R SR Left Hand :58775(58,8%) Right Hand :40571 (40,6%) Home row (Ill) :23677 (23,7%) Bottom row (IV): : 15228(15.2%) (favorable) (unfavorable)MISCELLANEOUS CRITERIA(relative frequencies for 100.000 digraphs) Alternations:50192 (50%), GG: 19042 DD: 8977 : 28019 (28%) with unfavorable stroke direction: 11525 3833 15358 (15%) Jumps :3067 (3%) Adjacencies: 5652 (5T9G) Repetitions :2729 (2,7%) (independant to keyboard)Big steps by order of decreasing difficulty (favorable and unfavorable directions not taken into consideration) 4=5 3=4 2=4 3=5 2=5 2=3 Total
L: 453 348 84 1353 1450 1445 5133 #9288 (9,3%) R: 19 20 2504 9 89 1514 4155 Number of words to be typed solely on row 111:0 Number of words to be typed entirely with the left hand :790Horizontal length travelled by the fingers for 100.000 strokes :3216 m TABLE 3PERFORMING STATISTICAL RESULTS FOR THE FRENCH LANGUAGE OF THE FRENCH RATIONALKEYBOARD OF FIGURE 1LOADS (relative frequencies for 100.000 characters) Left Hand Right Hand6440 7296 14231 15538 2238 4251 19885 8750 9255 114575 4 3 2 1 1 2 3 4 5TOTAL :45743 (45,7%) TOTAL: 53598 (53,6%)Home row (Ill): 72687 (72,7%) Bottom row (IV): :3130(3,13%) (favorable) (unfavorable)MISCELLANEOUS CRITERIA(relative frequencies for 100.000 digraphs)Alternations:Little steps71523 (71,50%) GG: 10987 DD: 12795 GG + DD: 23682 (23,7%)with unfavorable stroke direction: 5467 4624 10091 (10,1%) Jumps:15 (0,015%) Adjacencies : 503 (0.50%) 'Repetitions : 2732 (2,73%)(independant to keyboard)Big steps by order of decreasing difficulty (favorable and unfavorable directions not taken into consideration) 4=5 3=4 1,2=4 3=5 1,2=5 1,2=3 Totals
G: 0 130 26 7 11 84 258 # 499(0,50%) D: 53 2 0 59 4 123 241 Big steps not detrimental : 171Difference: 328 (0,33%)Number of words to be typed solely on row Ill: 2500Number of words to be typed entirely with the left hand: 17Horizontal length travelled by the fingers for 100.000 strokes: 1327 m TABLE 4PERFORMING STATISTICAL RESULTS FOR THE FRENCH LANGUAGE OF THE INTERNATIONALKEYBOARD OF FIGURE 16LOADS (relative frequencies for 100.000 characters) Left Hand Right Hand5783 7214 15451 15334 2238 7268 12306 10587 11747 113795 4 3 2 1 1 2 3 4 5TOTAL :46020 (46%) TOTAL: 53287 (53,3%)Home row (III): 68198 (68,2%) Bottom row (lV) : 3581(3,58%) (favorable) (unfavorable)MISCELLANEOUS CRITERIA(relative frequencies for 100.000 digraphs)Alternations:Little steps:71517 (71,50%) GG: 11314 DD: 11864 GG+DD: 23178 (23,2%) with unfavorable stroke direction: 5760 7499 13259 (13,3%)Jumps : 3 (0,003%) Adjacencies : 834 (0.83%) Repetitions :2732 (2,73%)(independant to keyboard)Big steps by order of decreasing difficulty (favorable and unfavorable directions not taken into consideration) 4=5 3=4 1,2=4 3=5 1,2=5 1,2=3 Totals:
G: 0 128 20 6 6 231 391)@ @673(0,67%) D: 4 36 130 0 60 52 282) Big steps not detrimental : 316Difference: 357 (0,357%) TABLE 5PERFORMING STATISTICAL RESULTS FOR THE FRENCH LANGUAGE OF THE FRENCH RATIONALKEYBOARD OF THE FIGURE 21LOADS (relative frequencies for 100.000 characters)Left Hand Right Hand6440 7245 15451 16505 2238 4251 14254 12101 9820 122945 4 3 2 1 1 2 -' 3 4 5TOTAL :47879 (47,9%) TOTAL: 52720 (52,7%)Home row (Ill): 71445 (71,4%) Bottom row (IV) : 3259 (3,26%) (favorable) (unfavorable)MISCELLANEOUS CRITERIA(relative frequencies for 100.000 digraphs)Alternations:Little steps:71356 (71,4%) GG: 12021 DD: 11415 GG+DD: 23436 (23,4%)with unfavorable stroke direction: 5830 3535 9365 (9,36%) Jumps :25 (0,025%) Adjacencies: 755 (0.755%) Repetitions: 2731' (2,73%)(independant to keyboard)Big steps by order of decreasing difficulty (favorable and unfavorable directions not taken into consideration) 4=5 3=4 1,2=4 3=5 1,2=5 1,2=3 Totals:
G: 0 128 20 11 11 223 393 651 (0,65%) D: 0 4 0 52 3 199 258 Big steps not detrimental : 368Difference: 283 (0,28%) Horizontal length travelled by the fingers except the thumbs: 1281 m