US3534846A

US3534846A - Typewriter for braille dots

Info

Publication number: US3534846A
Application number: US689386A
Authority: US
Inventors: Masaharu Watari
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-12-10
Filing date: 1967-12-11
Publication date: 1970-10-20
Anticipated expiration: 1987-10-20
Also published as: GB1211218A; FR1561978A

Description

I Och 1970 MASAHARU WATARI 3,534,846

TYPEWRITER FOR BRAILLE DOTS Filed Dec. 11, 1967 8 Sheets-Sheet 1 INVENTOR. MA SAHARU WATARI ATTORNEY Oct. 20, 1970 MASAHARU WATARH 3,534,345

TYPEWRITER FOR BRAILLE DOTS Filed Dec. 11, 1967 8 Sheets-Sheet 2 H HI INVENIUR. MASAHARU WATARI ATTORNEY Oct. 20, 1970 MASAHARU WATARH TYP EWRITER FOR BRAILLE DOTS Filed Dec. 11, 1967 8 Sheets-Sheet 5 lll MASAHARU WATARI ATTORNEY 1970 MASAHARU WATARI 3,534,846

TYPEWRITER FOR BRAILLE DOTS 8 Sheets$heet 4 Filed Dec. 11, 1967 mm @mw m. Nb w INVENTOR. MASA HARu NA TAR! ATTORNEY 1970 IMASAHARU WATARI 3,534,846

TYPEWRITER FOR BRAILLE DOTS Filed Dec. 11, 1967 8 Sheets-Sheet 5 BY NA SAHARU wATARl FIG. 5

ATTORNEY Oct. 20, 1970 MASAHARU WATARI 3,534,846

TYPEWRITER FOR BRAILLE DOTS 8 Sheets-Sheet 7 Filed Dec. 11, 1967 .=wol m o m:zt zo=zmu a vzumnwxwwiNzam mm m QE IN\ 'E.'\'T( I12. MASAHARU WATARI BY WAZ ATTORNEY Oct. 20, 1910 Filed Dec. 11, 1967 MASAHARU WATARI 3,534,846

TYPEWRI'I'ER FOR BRAILLE DOTS 8 Sheets-Sheet 8 LWENTQR. MASAHARU WATAR:

ATTORNEY United States Patent TYPEWRITER FOR BRAILLE DOTS Masaharu Watari, 7-14 Tsuda-Hamano-cho. Tokushima-shi, Tokushima-ken, Japan Filed Dec. 11, 1967, Ser. No. 689,386 Claims priority, application Japan, Dec. 10, 1966, 41/ 81,120 Int. Cl. B41 3/32 US. Cl. 197--6.1 6 Claims ABSTRACT OF THE DISCLOSURE Braille dot character typewriter comprising six pin elements supported freely on a typing base for extension therefrom and retraction therein to respond to recesses on the type heads, and a transmission mechanism connected with said pin elements and the keys controlling the type heads, wherein during typing Operation of the type bars, code bars are operated so that only pins corresponding to the recesses on the type head, being brought into typing position, are disposed in positions projecting from the typing base while the other pins are retracted in the typing base before the typing of the Braille character, so that typewritten characters on a medium between the pin elements and type heads are finished more finely.

This invention relates to a typewriter for Braille dots.

Typewriters for Braille dots have hitherto been known in the art, as indicated by US. Pat. No. 3,032,164. Such typewriters have a plurality of type bars operable by pushing type keys; a plurality of type heads respectively fixed on one end of the said type bars having one or more recesses formed therein correspondingly arranged in the form of Braille dots or characters in opposite left and righthand columns; a typing base provided at the typing position of said type head; and six pin elements connected in the typing base, some of which are always held in a position projecting from the typing base by spring means, wherein during typing of the type bars, the Braille dots are typed on and impressed in the paper provided in front of the typing base by cooperation of the recesses in the type heads and the six pin elements corresponding therewith.

In such typewriters, six pin elements are always held in a position projecting from the typing base and the pins which do not have corresponding recesses in the type heads during typing are pressed forcibly into the typing base by the flat part of the type head, whereupon the tip ends of the pins which do not have corresponding recesses leave pin traces or small impressions on the back side of the paper, said traces also appearing on the front surface of the paper. Therefore, the paper has small pin impressions or traces left beside the more prominent Braille dots and this causes one to feel an extremely unclean impression. Furthermore, when a blind person reads the paper, the small pin traces give him an uncomfortable, uncertain and confusing feeling, and often results in misreading. In addition, such traces often appear more distinctly in thin papers so that satisfactory typing of the Braille dots cannot be effected.

An object of this invention is therefore to provide an excellent typewriter for Braille dots which comprises simple code bars for removal of such disadvantages and the typewriter characters may be finished more finely by makice ing the pins which do not correspond to the recesses on the type heads during the typing disappear instantly before typewriting.

Another object of this invention is to provide a high speed power drive typewriter for Braille dots which is easy for communication from the blind to the blind or to the non-blind, or from the non-blind to the blind, and which provides a quite simple and convenient way for the non-blind to learn Braille dot characters.

Still other objects of this invention will be more fully understood from the following description and the accompanying drawings, in which:

FIG. 1 is a plan view of a typewriter for Braille dots embodying this invention;

FIG. 2 is an enlarged cross-sectional view of the embodiment taken on a plane along the line 2-2 in FIG. 1;

FIG. 3 is a cross-sectional view showing the typewriter for Braille dots in FIG. 2, actuated to an operating I position;

FIG. 4 is an enlarged back elevational view of the typewriter showing the essential parts on the back face of the embodiment with the rear cover and carriage of the typewriter being removed for clarity;

FIG. 5 is a perspective view showing the printing part of the typewriter for Braille dots according to the invention in which part of the paper used is partly broken away;

FIG. 6 is an enlarged view of an example of a type head;

FIG. 7 is an enlarged longitudinal sectional view taken on a horizontal plane along the line 77 of FIG.

FIG. 8 is an enlarged back view of a fragmentary portion of FIG. 4, showing the rear printing part of the typewriter;

FIG. '9 is a schematic diagram of a code bar used in the typewriter for Braille dots according to this invention; and

FIG. 10 is a schematic diagram showing a middle bar selectively operated by the code bar of FIG. 9.

One exemplary embodiment of the invention is shown in the drawings. The Braille dots typewriter of this embodiment can type the letters consisting of six dots. Explaining the method diagrammatically, a typing base is provided which retains six pin elements projecting therefrom and arranged in two rows of three pins each in the longitudinal direction of the base. The type bars, which are plural in number, are provided with type heads which have one or more recesses formed therein, corresponding to the left and right columns and opposite sides of Braille character dots in appearance. Further, the paper is positioned in front of the typing base. If the type bar is operated for typing in some condition, the recesses on the type heads and the pins corresponding thereto cooperate, and register and type or impress the dots on the paper.

While the Braille dots typewriter of this invention is adapted to type Braille dots it can additionally simultaneously type the letters, figures, or marks corresponding to such dots. In a schematic diagram of this method, the type head is shown to have a recess for a Braille dot and also to have a type of a letter, figure, or mark corresponding to the dot. In this Braille dots typewriter, a rubber plate is fitted to the typing base and placed at a typing position of the type to serve as a platen, so the type may be typewritten by the same method as in ordinary typewriters. With this arrangement it is possible, by displacing the position of the rubber plate on the typing point, to type only Braille dots.

Furthermore, the Braille dots typewriter in this embodiment is of the character having a power drive means and the typing operation of the type bars is carried out by a snatch roll for driving the type bar and the typewriter is connected operationally to a motor through adequate transmission mechanism.

The inventiton will now be more fully described with reference to the illustrated exemplary embodiment in the accompanying drawings.

In the drawings, is a typewriter base, on the left and right sides of which are provided the vertical side frames 11, 12. The upper parts of both side frames are connected with a plurality of transverse crosspieces 13, '14, 15, 16. A rear vertical cover 17 is connected at the rear end of the base 10 and side

vertical covers

18, 19 are fixed to the left and right sides of the base. An upper cover 20 is provided so as to partly envelope the said base 10. A motor 21 is connected on the rear and upper face of the base 10, the electric supply to which is controlled by a switch 22 on one side cover 19. 23 designates a snatch roll for driving the type bar, which is rotatably supported by said side frames 11, 12 so as to be disposed in the transverse direction above the middle part of the base 10, operatively connected with the motor 21 by adequate transmission mechanism to be capable of always revolving in the clockwise direction as seen in FIG. 2. A plural number of teeth 23a, extending in the axial direction, are formed on the periphery of snatch roll 23. A plurality of key levers 24, the rear ends of which are pivotally connected to transverse crosspiece 13 by a support pin 25, are respectively fitted with keys 26 on the front ends thereof. An arm 24a, projecting downwardly and slightly rearwardly, is formed below the medial portion of each key lever 24.

Between said plurality of key levers 24 and the later described plurality of type bars 47 operational connection mechanism is respectively connected, the construction of which is illustrated in more detail in FIGS. 2 and 3, disclosing a progressing single typing action.

The medial portion of the sub lever 27, corresponding to said key lever 24, is pivotally connected to the transverse crosspiece 13 by a support pin 28. Spring 30 connected between the lower end of sub-lever 27 and slot plate 29, fixed to the crosspiece 13, rotatably biases sublever 27 in the counterclockwise direction as seen in FIG. 2. Further, the front part of sub-lever 27 is in contact with the arm 24a of key lever 24, which lever is ordinarily retained at the initial position as shown in FIG. 2, by the bottom of the slot plate 29. A hook operating lever 31 corresponding to the sub-lever 27, is pivotally connected at its medial portion by pivot pin 32 to the upper part of sub-lever 27. A spring 33 is connected between the front end of hook operating lever 31 and the upper end of sub-lever 27 which operates to forcibly urge hook operating lever 31 in the counterclockwise direction as seen in FIG. 2. Further, the hook operating lever 31 is formed with a through hole 34 in which a pin 35 is located which projects from the sublever 27. Therefore, engagement of the through hole 34 and pin 35 apparently limits the revolvable movement in the clockwise and counter-clockwise direction of the hook operating lever 31. 36 designates an L-shaped bell crank, the middle portion of which is rotatably pivoted on crosspiece 14 by support pin 37 and a long slot 38 is formed in the front portion thereof. In this long slot 38 a pivot pin 39 is engaged for sliding movement in the longitudinal direction of the slot, and the pivot pin 39 is rotatably pivotally connected to an engaging book 40 at the middle portion thereof. The lower end of the engaging hook 40 extends to the front of the snatch roll 23 and is positioned for engagement with the teeth 23a of the snatch roll. A stepped portion 40a at the upper end of engaging hook 40 is ordinarily engaged by the stepped portion 31a on the rear end of the hook operating lever 31. Reference numeral 41 designates an operating member for operating a later described code bar 91. The rear end of operating member 41 is rotatably supported on the periphery of a fulcrum 42 formed on the crosspiece 15, and the front end of the member extends forwardly above the snatch roll 23 and supports the pivot pin 39 between the engaging hook 40 and the bell crank 36. A spring 43 is also connected between operating member 41 and crosspiece 15, whereby the operating member 41 is ordinarily raised to an upper position by action of the spring 43, and when the bell crank 36 revolves, it revolves in the clockwise direction, as seen in FIG. 2, around the fulcrum 42. Further, a spring 44 is connected between the front end of operating member 41 and the engaging hook 40. The spring 44 forcibly biases the engaging hook 40 in the counterclockwise direction (FIG. 2), while ordinarily retaining the lower end of the engaging hook 40 in a rest position (FIG. 2) spaced from the teeth 23a of snatch roll 23. A through hole 45, almost in the middle of engaging hook 40 engages a pin 46, projecting from the operating member 41. Accordingly, by engagement of the through hole 45 and the pin 46, rotation of the engaging hook 40 in the clockwise and counterclockwise directions about the pivot pin 39 is very much limited.

A plurality of type bars are represented at 47 corresponding to the keys 26. The lower portions of the type bars 47 are rotatably supported by the support pin 49 respectively in the slots 48a of a type bar segment 48 fixed between the side frames 11, 12. Links 50 are respectively provided between One end of the type bars and the bell cranks 36 and through described operating connection mechanism are operatively connected to the key levers 24. A type head 51 is respectively fixed on the other end of each key bar 47, and on each type head 51 a recess 52 or a plurality of such recesses are provided in a symmetrical shape corresponding to a Braille dots character and a type character 53 corresponding thereto is provided beneath the dots. FIG. 6 shows as an example a type head 51, a type letter P, and a series of recesses 52 corresponding respectively thereto, for forming the corresponding Braille dot character.

Spring 54 respectively connected between bell crank 36 and crosspiece 15, normally urges bell crank 36 to revolve in the counterclockwise direction as seen in FIG. 2, and the type bar 47 is ordinarily retained at a rest position on the type bar rest 55 provided between the side frames 11, 12. On the other hand, when the key lever 24 revolves by pushing down on key 26, the engaging hook 40 revolves in the clockwise direction, as seen in FIG. 2, around pivot pin 39 and engages with one of the teeth 23a of the snatch roll 23. In accordance with this operation, rotation of the snatch roll 23 revolves bell crank 36 against the action of spring 54 in the clockwise direction (FIG. 2) and the type bar 47 is rotated around to the typing position as shown in FIG. 3, where upon engaging hook 40 revolves around support pin 37 with the rotation of snatch roll 23. Engaging hook 40, however, is released from the teeth 23a of the snatch roll 23 when it engages the screw 56 on the table or base 10. The screw 56 of each hook can be adjusted in the forward and rearward directions in order to control the disengagement movement of each engaging hook 40 from the teeth 23a of the snatch roll 23.

The typing part for typing Braille dots and letters by typing of said type bar 47 will now be described particularly with reference to FIGS. 4, 5, 7 and 8.

In the drawings, 57 is a typing base, the front shape of which is nearly U-shaped and which is slidably movable in the longitudinal direction in slot 58 in crosspiece 16. The typing base is adjusted to move slidably from its position of accommodation to the position of use as shown in FIG. 4. The crosspiece 16 is fixed with a plate spring 61, the free end of which will press the back surface of the typing base and obstruct undesired sliding of the typing base. A pin support plate 62 is screwed at 63 to the front of the typing base 57, and has six holes 64- formed therethrough. A box 65 is screwed at 66 on the back of the pin support plate 62, and is accommodated in an opening 67 formed in the typing base 57. Six pin elements 68, cooperating with the recesses 52 of the type head 51, are inserted in through holes 64 of pin support plate 62 from one side of box 65, for movement from positions projecting from and retracted beneath pin support plate 62. Described as shown in FIGS. and 9, but marked in FIG. 8, the six pin elements are designated as 68a, 68b, 680, in the left row from top to bottom and as 68d, 68e, 687 in the right row from top to bottom. The positions of the pins 68 are also shown diagrammatically in FIG. 9. A rubber plate 69 is connected in front of the pin support plate 62 below the pins 68 and is the equivalent of a platen. Rubber plate 69 is slidably in a longitudinal slot 70 formed in pin support plate 62. When simultaneously typing Braille dots and the equivalent letters, the rubber plate '69 is positioned at the typing position of the type character 53, while, when typing only Braille dots, the rubber plate 69 is slidably moved to a position out .of the typing position of the type characters 53 and retained in that position. Rubber plate 69 has a handle 71 projecting to one end of typing base 57 and is adapted to be slidably moved by movement of this handle 71.

Having thus described the typing portion, we shall now describe the transmission mechanism provided between the pins 68 and the later described code bars 91 for moving the six pin elements 68 to retracted positions in response to the recesses 52 of the type head 51.

Reference numeral 72 designates six pin operating levers respectively corresponding to the six pins 68. The middle portions of the pin operating levers 72a, 72b, 720, corresponding to the pins 68a, 68b, 686, are pivoted above one another on a shaft 73 in box 65 and the middle portion of pin operating levers 72d, 72e, 72f, corresponding to the pins 680], 68e, 68 are pivoted above one another on another shaft 74 in box 65. As shown in FIG. 7, the upper ends of the operating levers 72 are respectively in contact with the rear ends of the six pins 68. A spring 75 is connected between the rear end of each lever 72 and the box 65, to forcibly urge each pin operating lever into contact with the six pins to hold them in positions projecting from the upper surface of pin support plate 62. Three sub-levers 76d, 76c, 76 respectively corresponding to and engaging the three pin operating levers 72d, 722, 72 are pivoted on shaft 77 in box 65. Wire 78a, 78b, 78c, 78d, 78e, 787 are respectively connected at the end thereof with the rear ends of

pin operating levers

72a, 72b, 72c and with the rear ends of sub-levers 76d, 76a, 76 By drawing the wires 78a, 78b, 780 to the right in FIG. 7, the pin operating levers 72a, 72b, 720 respectively connected thereto are pivoted in the counterclockwise direction about shaft 73 and against the action of springs 75, while by drawing the wires 78d, 78e, 78 to the right in FIG. 7, the

sub levers

76d, 76c, 76 respectively connected thereto are pivoted in the counterclockwise direction about shaft 77. The pin operating levers 72d, 72e, 72; corresponding to these sub-levers 76 are pivoted thereby in the clockwise direction, as seen in FIG. 7, about the shaft 74 and against the action of springs 75. If a pin operating lever 72 pivots or rotates against the action of its spring 75, the pin 68, which has been pressed in a position projecting from support plate 62 is retracted beneath the surface of the pin support plate by gravity action. According to this embodiment, pin 68 and the pin operating lever 72 are merely in contact engagement, and if the pin 68 is released from the upward biasing force of the pin operating lever 72, it immediately slides downwardly in the inclined through hole 64 by action of gravity into the pin support plate 62. It may of course be possible to employ other methods for attaining the same result, such as by directly connecting the pin 68 and the pin operating lever 72 by suitable connection means to force the pin 68 to plunge into pin support plate 62 by rotation of the pin operating lever 72. In FIG. 4, six levers 79 re spectively corresponding to pin operating levers 72a, 72b 72c and sub-levers 76d, 76e, 76], are shown rotatably pivoted at their mid-portions respectively on the shafts 80 or 81 on the side end of typing base 57, with the upper ends of the levers 79 respectively connected to the opposite ends of the wires 78. Three of the levers 79 are pivoted on the shaft 80, one above the other, and are connected in the order of sequence as viewed from the front of the machine to the other ends of the wires 78a 78b, 780. The other three levers 79 are pivoted on shaft 81, one above the other, and are connected in the order of sequence as viewed from the front to the other ends of the wires 78d, 78e, 78 Six L-shape levers 82 corresponding to the levers 79 are rotatably pivoted at their midportions, in two groups of three each, one behind the other, on

shafts

83 or 84 supported on crosspiece 16. The upper ends of these L-shaped levers 82 and the lower ends of the levers 79 are connected by individual connection means consisting of a chain 85 and a wire 86. The three L-

saped levers

82a, 82b, 82c pivoted on shaft 83 are connected in the order as viewed from the front of FIG. 4, to the respective levers 79 pivoted on shaft 80, and the L-shaped

levers

82d, 82c, 82 pivoted on shaft 84 are connected in the same order to the respective levers '79 pivoted on shaft 81. Six middle levers 87 are spaced at some distance in the longitudinal direction, above the typing base 10 (FIG. 4) from the corresponding L-shaped levers 82, and as shown in FIG. 2 and 3, these are respectively rotatably pivoted on shaft 88 supported by side frames 11, 12 adjacent the front ends thereof. A spring 89 is connected between each middle lever 87 and crosspiece 15 which acts to revolve each middle lever 87 in the clockwise direction, as shown in FIG. 2, around the shaft 88. A transmission spring 90 is connected between the rear end of each middle lever 87 and the lower end of the corresponding L-shaped lever 82. If said middle levers 87 are designated 87a, 87b, 87c, 87d, 87e, 877, as shown in FIG. 4, they are respectively connected in this order of sequence to the corresponding shaped

levers

82a, 82b, 82c, 82d, 82e, 821, and the

middle levers

87a, 87b, 87c, 87d, 87s, 87 are then connected in the order of sequence to the

pin operating levers

72a, 73b, 72c, and sub-levers 76d, 76e, 76 respectively. Accordingly, the

middle levers

87a, 87b, 87c, 87d, 87e, 87f correspond in the order of sequence to the

pins

68a, 68b, 68c, 68d, '68e, 68f. It may therefore be understood from the above description that if one middle lever 87a is actuated, one pin 68a will retract into the pin support plate 62.

The foregoing provides a description of the construction of the transmission mechanism. An explanation will now be given concerning the code bar mechanism for selectively operating the above described six pins 68, particularly with reference to FIGS, 2, 4, 9 and 10.

Code bars 91 are arranged with only a slight spacing below the plurality of operating members 41, and are arranged transverse of the respective middle levers 87. Arms are provided on both ends of the code bar 91 having a curved shape and extending at right angles to the bar. Both arms of each code bar are rotatably pivoted respectively on shaft 88 (FIG. 4) and the six code bars 91 are designated 91a, 91b, 91c, 91a, 91e, 91 as shown in FIG. 2. The middle levers 87 are located below each of the code bars 91. As shown in FIG. 10; longitudinal notches 92 are provided on the upper edges of the middle levers 87, and projections 93 are provided in the notches, each corresponding to a code bar 91 at its crossing position with the respective levers 87. The lower ends of

code bars

91a, 91b, 91c, 91d, 91e, 91f engage with the projections 93 of the

middle levers

87a, 87b, 87c, 87d, 87e, 87 in the order of sequence. Therefore, if one code bar 91a is pushed down, only the middle lever 87a will be pushed down and the other

middle levers

87b, 87c, 87d, 87e, 87f will be held in their rest positions; so that it is apparent that if the

code bars

91a, 91b, 91c, 91d, 91e, 91 are operated in sequence, the

pins

68a, 68b, 68c, 68d, 68c, 68 will retract into the pin support plate 62 in the same order of sequence through operation of each mid dle lever and the transmission mechanism. An operating member 41 is connected above the code bar 91 in transverse relation therewith. As previously described, the operating member 41 revolves about the fulcrum 42 in the clockwise direction (FIG. 2) upon operating the type bar 47. FIG. 9 diagrammatically shows the six code bars 91. Projections 94 and valleys 95 are respectively formed on the upper edges of each code bar 91. In the figure, thin vertical lines crosing each code bar 91 show an arrangement of operating members 41 Which are operative when the key 26 corresponding to the letters, figures, or marks shown thereabove are pushed down. The six dots shown on the side of code bars 91 represent the six pin elements 68. Among these dots, the one which is particularly in black represents the position of the pin which is retracted into the pin support plate 62 by operation of the corresponding code bar 91. If the code bar 91 below one operating member 41 has a projection 94, that code bar 91 is pushed down by downward movement of the operating member 41 and the pin 68 connected thereto retracts into the pin support plate 62. If the code bar 91 corresponding to the said operating member 41 has a valley 95 beneath the member, the code bar 91 is retained at a rest position despite the downward movement of the operating member 41 and the pin 68 connected thereto remains in a position projecting from the upper surface of the pin support plate 62. By combinations of these projections 94 and valleys 95 on the six code bars 91, the pins 68 in the left and right columns and in both columns can be selectively operated in response to the shape of the Braille dots characters. In case, as for example, a letter P and its dots shown in FIG. 6 are typed, the pins 68e, 68f will retract into the pin support plate 62 since these do not have corresponding recesses 52 on the type head 51. This is because the code bars 91:2 and 91f related to the pins 68e and 68] have projections formed thereon beneath the operating member 41 of the letter P, as shown in FIG. 9, and the

other code bars

91a, 91b, 91c, 91d related to the

pins

68a, 68b, 68c, 68d have valleys 95 formed thereon in this position. Accordingly, upon typing the type bar 47, only the code bars 91c and 91] are pushed down by the downward movement of the operating member 41 corresponding to P, and the pins 68e and 68f connected thereto retract into the pin support plate 62.

A brief description will now be added on a carriage part provided in the rear part of the above described printing part.

Carriage 96, slidably connected in guide 97 on crosspiece 16, is adapted to proceed in the direction of type feeding by means of ordinary escapement mechanism (not shown), when a key 26 or space bar 98 is pushed down. The carriage 96 has a paper feeding mechanism for feeding paper 99 into the typewriter.

The carriage 96 has a rotatably supported carriage shaft 101 with knobs 100 on both ends thereof. The carriage shaft 101 has a gear wheel 102 fixed thereto, which has two

wheels

103, 104 provided in the upper and lower parts of the carriage in engagement therewith. The two

wheels

103, 104 are respectively engaged with pinions (not shown) connected on the upper and

lower roller shafts

105, 106. Each of the

roller shafts

105, 106 has the

rubber rollers

107, 108 respectively fixed thereon, which in turn are disposed in pressed rolling contact with rollers 109, .110 respectively. The paper 99 passes through the lower pair of

rollers

108 and 110 and is fed to the front of the pin support plate 62 from the typing base 57, and from the front of 62 is fed back through a pair of

upper rollers

107 and 109. Therefore, if the carriage shaft 101 is revolved by knob in the counterclockwise direction in FIG. 2, the rotation of the carriage shaft 101 is transmitted to the upper and

lower roller shafts

105, 106 through the upper and lower gear wheels .103, 104 and said

roller shafts

105, 106 revolve in the counterclockwise direction as seen in FIG. 2. As a consequence, the upper and lower rollers 109, revolve with the

rollers

107, 108 corresponding therewith and the paper is fed as described above. The carriage 96 and the typing base 57 also have

guide plates

111, 112 and 113 rigidly fixed thereto to guide the feed of the paper 99.

The following is a description of the operation of this invention with the construction mentioned above and with reference to the embodiment illustrated in the drawrngs.

FIG. 2 shows a stationary condition of the Braille dots typewriter of this embodiment. In this stationary condition, the switch 22 is operated to energize motor 2.1, which in turn actuates the snatch roll 23 to revolve it in the clockwise direction as seen in FIG. 2. Thereafter, a selected key 26 may be pushed down and then the key lever 24 will revolve in the clockwise direction around support pin 25 and the arm 24a of the key lever 24 will push the middle portion of sub-lever 27 rearwardly. By pushing this middle portion, the sub-lever 27 revolves in the clockwise direction around the support pin 28 against the restraining action of spring 30. Rotation of sub-lever 27 causes hook operating lever 31 to move forward, and the engaging hook 40 engaged with the stepped portion 31a of hook operating lever 31 revolves against the biasing action of spring 44 in the clockwise direction around the pivot pin 39. By this rotation, the lower end of engaging hook 40 meshes with the rotating teeth 23a of snatch roll 23. The rotation of snatch roll 23 causes engaging hook 40 to move downwardly into contact with the screw 56, which causes the lower end of the engaging hook to separate from the teeth 23a of snatch roll 23. The downward movement of engaging hook 40 is transmitted to bell crank 36 through the pivot pin 39 so that the bell crank 36, in resisting the action of spring 54, pivots around support pin 37 in the clockwise direction as shown in FIG. 2. Accordingly, the revolving action of the bell crank 36 is imparted to the type bar 47 through the link 50, causing the type bar to rotate around support pin 49 toward the typing position of FIG. 3 from the stationary position of FIG. 2.

The downward movement of engaging hook 40, rotates operating member 41 in the clockwise direction as seen in FIG. 2 about the fulcrum 42, against the resisting action of spring 43. Rotation of operating member 41 selectively actuates the six code bars 91, and as described makes a selected pin or pins 68 retract into the pin support plate 62. Thereafter, the type bar 47 rotates further counterclockwise by inertia from the force provided from the snatch roll 23 and the type head 51 strikes the paper 99 on the typing base thus carrying on a typing operation, as shown in FIG. 3, by impressing Braille dots into the paper where the pins 68 and recesses 52 register with each other, and simultaneously printing the corresponding character on the paper.

A further description now follows on the timing between the typing action of the type bar 47 and that of the pin 68 retracting into the pin support plate 62.

While the type bar 47 continues typing motion from the stationary position to the typing base 57, the pin 68 which does not have a corresponding recess 52 on the selected type head 51 recedes gradually as described. Thus, immediately before the type head 51 collides with the paper at the typing position, the pin 68 retracts completely into the pin support plate 62, Therefore, only the pin or pins 68 corresponding to the recess or recesses 52 on the type head 51 will remain projecting from the pin support plate 62 and will allow fresh Braille dots to be impressed into and appear on the paper 99 without leaving misleading striking traces thereon.

FIG. 3 shows the typing operation of marks in which code bars 91a and 91d are pushed down. The six middle levers 87 which have been pushed down by operation of the code bars 91 may vary in depth or degree of rotation from one another. The degree of rotation is made progressively greater in sequence in the order of the

middle levers

87f, 87e, 87d, 87c, 87b, 87a. In accordance with this arrangement, the tension of the transmis sion springs 90 varies with the position of the respective middle levers 87. Therefore the resiliency of the transmission springs 90 controls the drawing of each L-shaped lever 82 to a considerable extent. Further the arm of each L-shaped lever 82 to which the corresponding transmission spring 90 is fixed varies in length from the

shafts

83 and 84 and the transmission springs 90 with increasingly greater tension are fixed on a much longer arm in the above order of sequence, whereby the angle of revolution of each L-shaped lever 82 remains nearly constant and operation of each pin 68 is uniform.

The carriage 96 moves in one step by operation of the escapement mechanism after the Braille dots have been typed on the corresponding portion of the paper 99, whereby the typing operation is accomplished and all mechanisms return to the stationary position from the operational position of FIG. 3. This operation is the same as in ordinary typewriters.

In this return operation, the engaging hook 40 separated from snatch roll 23 is revolved at once in the counter-clockwise direction of FIG. 3 by action of spring 44. The type bar 47, after striking the typing base 57 is returned to the position of FIG. 2 by the spring 54 of bell crank 36, While the operating member 41 revolves about the fulcrum 42 in the counterclockwise direction as seen in FIG. 3, and releases the code bar 91 which it had pushed down. Consequently, code bar 91 and the middle lever 87 rise together under action of the spring 89 and return to the rest position as shown in FIG. 2. As the middle lever 87 which has pushed down returns to the stationary position, all the transmission mechanism including the middle lever 87 to the pin operating lever 72 comes to the rest position as shown in FIG. 2. Accordingly, the pin 68 retracted into the pin support plate 62 is pushed outwardly and held in the position projecting from the pin support plate 62 by the corresponding pin operating lever 72.

Thus, one cycle of typing operation is accomplished by pushing key 26 at one time and by repetition of this operation it is possible to type Braille dots on the paper 99. The above description is concerned merely with the operation by means of one key only; however, the same will apply in case of operation of any key in use as will easily be understood. As had already been described, one may type only Braille dots, without letters, whereupon he may displace the rubber plate 69 out of the typing position.

With such construction as described above, the typewriter, in accordance to this invention, makes it possible to obtain finer Braille dots without leaving pin traces on the paper, which is quite comfortable for reading by blind persons, and presents no problem of misunderstanding the typed Braille dots.

In addition, by providing a construction enabling simultaneous typing of letters, figures, or marks equivalent to the Braille dots as shown in the embodiment, comm-unication between a blind person and a blind or non-blind person, or from a non-blind to a blind person may be made easier and more convenient for the non-blind, who lack the knowledge of the Braille dots alphabet, etc., and it is very simple for them to learn such alphabet, etc.

Furthermore, the rubber plate according to this embodiment can be constructed so as to be movable to the typing position of letters and also to a position out of the typing position whereby only Braille dots will be typed by simple operation of displacement of the rubber plate out of the typing position, and many other effects may also be obtained.

I claim:

1. A typewriter for impressing Braille dots on a medium comprising, a base, a plurality of key members connected in rows on said base, a plurality of corresponding type head portions, one or more recesses in each type head portion corresponding to Braille dot characters, a typing base at the typing impact position of said type head portons stationary with respect to said base, carriage means connected on said base for advancing the medium in front of said typing impact position, said typing base having a portion extending longitudinally beyond one end of the carriage means, first transmission means connected between said plurality of key members and said plurality of type head portions whereby upon actuation of a selected key member said first transmission means moves said coresponding type head portion into impact against said typing base at the typing impact position, a plurality of pin elements movably connected in said typing base at the typing impact position for movement from normally extended positions projecting from said typing base to positions retracted into said typing base and positioned to register with said recesses in said type head portions at the typing impact position, and second transmission means connected between said first transmission means and the rear of said plurality of pin elements biasing said pin elements to normally extended positions, said second transmission means operative by said first transmission means to maintain only said pin elements corresponding to the recesses in a selected head portion in positions projecting from said typing base and synchronously operative with said key members to retract the other said pin elements into said typing base before said type head portion registers the recesses therein with said extended pin elements at the typing impact position to impress Braille dots into the medium disposed therebetween, and a portion of said second transmission means extending longitudinally of said typing base portion and connected thereto at a position beyond one end of said carriage means.

2. A typewriter as set forth in claim 1, in which said plurality of pin elements correspond in number and position to the maximum possible positions of said recesses on said plurality of type head portions.

3. A typewriter as set forth in claim 1, in which said plurality of pin elements are connected at acute angles to the horizontal in upwardly sloping positions in said typing base, said second transmission means including biasing means operative to move said pin elements upwardly to normally extending positions projecting from said typing base, and said biasing means connected for movement away from said pin elements by said second transmission means, whereby said pin elements not having corresponding recesses in a selected head portion move downwardly in said typing base by force of gravity before said selected head portion impacts on said typing base.

4. A typewriter as set forth in claim 1, in which said second transmission means includes a plurality of code bars controlling the operation of said plurality of pin elements, and lever means connected for operation by said first transmisison means and to impart said operation to said code bars.

5. A typewriter as set forth in claim 4, in which the number of said code bars corresponds to the number of said pin elements.

6. A typewriter as set forth in claim 3, in which said lever means are connected transverse of said code bars, said code bars having upper edges adapted to contact and projections therealong.

11 said lever means, and said upper edges having recesses 2,842,245 3,032,164 3,253,691 References Cited 3,254,750 UNITED STATES PATENTS 5 4/1922 Steinkraus 1976.1 542 003 6/1930 Kurowski et a1 1976.1 9/1931 Smith 1976.1 6/1954 Frey et a1. 1976.1

12 7/1958 Frey 1976.1 XR 5/1962 Watari 1976.1 5/ 1966 Gollwitzer 1976.2 6/ 1966 Goldner 1976.1

FOREIGN PATENTS 12/1941 England.

EDGAR S. BURR, Primary Examiner