US3823804A

US3823804A - Braille typewriter

Info

Publication number: US3823804A
Application number: US00874220A
Authority: US
Inventors: R Lokey
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-11-05
Filing date: 1969-11-05
Publication date: 1974-07-16
Anticipated expiration: 1991-07-16

Abstract

A braille typewriter comprising a frame and a removable and linearly adjustable die plate having a series of sets of six protuberances or points thereon corresponding to all of the units of a braille cell, and a movable carriage having six keys each corresponding to a particular one of the six units of a braille cell, each actuating a lever having an indentation in its end whereby depression of one or more keys will emboss the specific unit or units of a braille cell for a specific letter on a sheet of paper passed between the platen and the keys. The device includes a spring biased carriage advancing mechanism and ratchet and pawl means for releasing the carriage for movement upon the completion of the printing operation.

Description

UnitedStates Patent [1 1 Lokey July 16, 1974 [54] BRAILLE TYPEWRITER 10,099 2/1909 Great Britain 197/6.1

............................... l [76] Inventor: Robert C. Lokey, Box 75356, 11O9850 10/1955 France 97/6 I Tamal, Calif. 94964 Primary Examiner-Robert E. Pulfrey [22] Filed: Nov. 5, 1969 Assistant Examiner-11. T. Radar 2 App] N 74 220 Attorney, Agent, or Firm-Blair & Brown [52] US. Cl. l97/6.1 [57] ABSTRACT A braille typewriter comprising a frame and a removable and linearly adjustable die plate having a series of sets of six protuberances or points thereon corre- [56] References Cited sponding to all of the units of a braille cell, and a mov- UNITED STATES PATENTS able carriage having six keys each corresponding to a 389,756 9/1888 McElroy 197/6.1 particular one of the six units of a braille cell, each ac- 443,977 12/1890 Sthreshley l97/6.1 tuating a lever having an indentation in its end 755,420 3/1904 Wayne 197/6.1 whereby depression f one or more keys will emboss the specific unit or units of a braille cell for a specific F ney letteron a sheet of paper passed between the platen ,762 l2/1966 Erickson 197/138 R a 1 and the keys. Thedevice lncludes a spring biased car- FOREIGN PATENTS OR APPLICATIONS riage advancing mechanism and ratchet and pawl 177,445 3/1922 Great Britain 197/6.1 means for releasing the carriage for movement upon 12,626 4/1906 Great Britain 197/6.1 the completion of the printing operation. 251,087 4/1926 Great Britain l97/6.l 177,292 3/1922 Great Britain l97/6,l

10 Claims, 18 Drawing Figures PATENTED L 1 6 974 SHEU 1 If- 5 INVEN TOR. 2055/97 (3 ZUKLX BRAILLE TYPEWRl-TER This invention relates to a braille typewriter and has as its primary object the provision of a simple, inexpen- A further object of the invention is the provision of such a device having means for automatically advancing the carriage by a single space corresponding to a braille cell together with a readily accessible spacer bar to advance the carriage as desired.

An additional object of the invention is the provision of means for clamping the paper in relation to the die plate to insure proper alignment of the braille cells.

Still another object of the invention resides in the provision of roller means for advancing the paper upon release of the clamping means.

A still further object of the invention is the provision of a device of this character which is sturdy and durable in construction, reliable and efficient in operation, and relatively simple and inexpensive to construct, operate and maintain.

Other objects will in part be obvious and in part be pointed out as the description of the invention proceeds, and shown in the accompanying drawings.

Briefly the invention comprises a frame including a fixed linearly adjustable die plate embossed with a series of braille cells each including six raised dots or points corresponding to all of the units ofa braille cell. Transverse guide bars mount a movable carriage which is spring biased to move from left to right. Six keys are provided'on the carriage, each operably connected to a lever having an indented end or female die portion corresponding in position to one unit of a'braille cell, whereby by depressing selected keys, any or all of the units of a desired braille cell may be simultaneously embossed on a sheet of paper extended over the die plate. Automatic ratchet and pawl spacer means are provided for releasing the carriage for advancement by the spring means after the selected character is imprinted, and means are provided for actuating the pawl independently of the actuation of the keys for spacing purposes. Clamping means for holding the paper are also provided.

In the accompanying drawings:

FIG. 1 is a top plan view of one form of device embodying the instant inventive concept;

FIG. 2 is a front elevational view thereof;

FIG. 3 is an enlarged front elevational view partially broken away and partially in section, disclosing a constructional detail;

FIG. 4 is an enlarged end elevational view as seen from the right of FIG. 1, partially in section;

FIG. 5 is an enlarged fragmentary top plan view showing the carriage and the mechanism shown in FIG.

FIGS. .6, 6A and 6B are enlarged detail front elevational views showing theratchet mechanism of the carriage in different positions of adjustment;

FIG. 7 is a sectional view taken substantially along FIG. 9 is a sectional view taken substantially along the line 9-9 of FIG. 8 as viewed in the direction of the arrows;

FIG. 10 is a sectional view taken substantially along the line 10-10 of FIG. 8 as viewed in the direction of the arrows;

FIG. 11 is a fragmentary side elevational view partially in section, of a constructional detail;

FIG. 12 is an enlarged top plan view partially broken away of a portion of the frame and platen;

FIG. 13 is a sectional view taken substantially along the line l 3l3 of FIG. 12 as viewed in the direction of the arrows; and

FIGS. 13A and 13B are views similar to FIG. 13 showing the parts in different positions of adjustment.

FIG. 14 is an enlarged sectional view showing a constructional detail;

Similar reference characters refer to similar parts throughout the several views of the drawings.

Having referencenow to the drawings in detail, the

device is generally indicated at and includes a frame 21 comprising a generally rectangular base plate. 22 having a first recess 23 therein. A male die plate 24 having threaded openings therein at each end is mounted in recess 23 by screws 26 extending through elongated slots permitting limited linear adjustment of die plate 24 for a purpose to be more fully pointed out hereinafter. Plate 24 carries a series of raised dots or points 27 arranged in spaced groups of six, the points corresponding to the six elements and positions of a braille cell.

A rectangular rear' carriage guide bar 30 extends transversely across base plate 22 and is secured in position by screws 31 at its ends engaging threaded bores in

end plates

32 and 33. Similarly, a front carriage guide bar 34 is secured by screws 35 in spaced parallel relation to bar 30. As seen in FIG. 4 guide bar34 is of generally L-shaped configuration.

Guide bars

30 and 34 are spaced upwardly from base plate 22 for a purpose to be described hereinafter.

End plates

32 and 33 each have upwardly extending

end blocks

36 and 37 respectively having aligned horizontal bores therein which serve as journals for the opposite ends 38 and 39 of a platen 40. End block 36 has an enlarged concentric recess 41 provided with an internal opening 42 which is adapted to receive one of a pair of diametrically opposed ball detents 43 which project from the ends of a bore 44 in a metal collar 45 carried by the adjacent end 38 of platen 40. A spring 46 biases detents 43 outwardly, the detents serving as an index bearing, when the platen 40 is rotated by means of an external knob 47 carried by end 39.

A vertical bore 48 in end block 36 carries a guide rod 49 for a bottom clamping roller release key 50 which carries a slide plate 51 provided with a projecting pin 52 which pivotally engages in one end of an operating link 53. A compression spring 54 in bore 48 normally biases rod 49 and key 50 upwardly. The other end of link 53 is fixed to an extending end portion 55 of a pivot'bar 56. Bar 56 is seated in a second recess 57 in base plate 22, and end portion 55 extends outwardly through a bore 58 extending through the end wall of recess 57 and end block 36 to engage link 53.

The opposite end block 37 is similarly arranged but omits the index bearing. A bottom clamping roller release key is mounted on a guide rod 66 seating in a bore 67 biased upwardly by a spring 68 and provided with a slide plate 69. Plate 69 carries a pin 70 pivoted in one end of a link 71, the opposite end of which is secured to the opposite end portion 72 of pivot bar 56. Pressure on either key or will serve to operate the device. Key 65 is however provided with a latch mechanism for securing the key in depressed position. The latch mechanism consists of a resilient flat spring means 73 which is secured by screws or bolts 74 to the forward end of block 37, and which has an outwardly flared end 75. A latching member 76 having a flat under surface 77 engages over the top of key 65 when the latter is fully depressed. The upper side 78 of latch 76 is arcuate to permit the underside of key 65 to slide thereover when depressed. Flared end permits ready release of the latch mechanismwhen desired.

Pivot bar 56 is rigidly connected to a bottom clamping roller 80 by means of spaced connecting members 81. Roller 80 comprises a rod-like portion 82 preferably metallic, to which the ends of members 81 are secured, and a series of resilient sleeves 83 which normally bear against resilient collars 84 mounted in spaced relation on platen 40, firmly holding a sheet of paper thereagainst, springs 54 and 68 providing sufficient force normally to urge pivot rod 56, and hence bottom clamping roller 80, to a position wherein sleeves 83 engage collars 84. Paper locating pins 85 are positioned on opposite ends of the forward edge of frame 21.

The carriage is generally indicated at and comprises a block 91 having oppositely disposed grooves or channels 92 and 93 in the sides thereof which engage

carriage guide bars

30 and 34 respectively, permitting linear sliding movement of the carriage. Block 91 has a central recess 89 across which extends a pivot pin 94 on which are pivotally mounted the stems 95 of each of six keys 96. The keys 96 extend three on each side in staggered relation, each key corresponding in relative position to one point of a braille cell, and are numberedfrom rear to front, corresponding to top to bottom on the paper to be embossed; 1, 2, 3 on the left side and 4, 5, 6 on the right side. The portion of each stem extending beyond the pivot 94 has a depending extremity 97, the bottom of which is provided with an indentation or female die 98, passing through an opening 99 in the bottom of block 91 in alignment with a corresponding point 27 on an underlying braille cell on male die plate 24. The slot and pin linear adjustment of die 24 previously described permits accurate initial alignment of die plate 24 with the carriage. Each extremity 97 is beveled as at 100 in order to compensate for the initial pivotal movement of its associated stem 95. An offset shoulder 101 on each stem has a recess 102 therein accommodating one end ofa compression spring 103, the

other end of which seats in an aligned depression .104

in the bottom of recess 89, springs 103 normally biasing each female die portion 98 upwardly to spaced relation relative to male die plate 24. Thus depression of selected keys simultaneously will imprint on a sheet of paper passed between the male and female dies any selected braille letter or symbol or abbreviation, none of which'consist of more than six points.

A spacer plate 105 overlies the top of block 91 and includes a pair of guide stems 106 extending into bores 107 in the top of block 91 on opposite sides of the recess 89 accommodating key stems 95. Compression springs 108 seat in top recesses 109 in the underside of plate 105 and aligned bores 110 in the top of block 91. A cover plate 111 held in position by screws 112 underlies spacer plate 105 and closes the top of recess 89 to preclude movement of key stems 95 past horizontal position. Side guide plates 114 extend from opposite sides of plate 105 along corresponding sides of block 91 and are provided with openings 115 through which key stems 95 extend.

A conventional spring biased reel is rotatably mounted on a pin 121 which extends through an opening in a depending rear portion 122 of cover plate 111 into block 91. Reel 120 carries a cord 123, the opposite end of which is secured in any suitable manner as by a pin 124 to righthand end plate 33, normally biasing carriage 90 from left to right.

An escapement mechanism is provided which permits carriage 90'to move one braillecell to the right, as biased by spring reel 120 and cord 123, upon release of one or more keys 96 or spacer plates 105 after depression thereof. The escapement mechanism takes the form of a rack extending the full length of the path of travel of carriage 90 having a series of teeth 131 each including a substantially perpendicular left hand portion 132 and an inclined right hand side 133. A pawl, generally indicated at 134, is mounted on a pin 135 carried by the front of block 91, and includes'an inclined tooth engaging tip portion 136 and an inclined bottom portion 137 corresponding to the angle of inclination of teeth 131.

Pawl 134 also has an inclined upper portion 137' terminating in a normally horizontal upper portion 138 and a normally horizontal lower portion 139. A pawl spring 140 includes a central loop 141 extending about pin 135 and has one end 142 underlying horizontal portion 139 and the other end 142a extending over inclined portion 137 biasing tip 136 towards tooth engaging position.

The pivoted mounting of pawl 134 includes an elongated slot 143, enabling pawl 134 to move linearly relative to pin 135 for a purpose to be described hereinafter, and a tension spring 144 overlying slot 143 having one end secured to pin 135, and its other end 145 secured to a pin 146 carried by pawl 134 adjacent the end of slot 143. l

An abutment 150 fixed to spacer plate 105, includes a shoulder 151 overlying the upper horizontal portion 138 of pawl 134 so that'depression of plate 105 tilts tip 136 out of engagement with an associated vertical portion ofa tooth 131. Abutment 150 includes a vertical bore 152 slidably mounting a pin 153 which extends downwardly to a detent 154, having a lower surface in cluding a first inclined portion 155 corresponding to the inclined portion 133 ofa tooth 131, and a stepped portion including a vertical face 156 and a second relatively short inclined portion 157. A compression spring 158 securing pin 153 between the bottom of abutment 150 and detent 154, normally biases detent 154 towards teeth l3l.An enlarged head 159 on pin 153 moving in an enlarged portion 160 of bore 152 limits downward movement of detent 154 to a point just clear of the top of vertical left hand portions 132 of teeth 131 when spacer plate- 105 is in normal position. Thus de-- pression of spacer plate 105, while releasing pawl tip 136 will move detent 154 into a position in which vertical face 156 engages the vertical'portion 132 of an adjacent tooth, retaining carriage 90 in position until the spacer plate 105 is released to return to normal position, at which time detent 154 will be moved out of tooth engaging position.

Spring 144 meanwhile will bias pawl 134 forwardly relative to the vertical portion 132 of the adjacent tooth, by virtue of the slotted connection with pivot pin 135, so that spring reel 120 through cord 123 will move the carriage one braille cell to the right, at which time tip 136 will engage the next adjacent vertical portion 132. Depression of any one'or more of keys 96 will, through the engagement of its associated stem 95 with the bottom 115a of recess 115, similarly depress spacer plate 105 to effect a similar movement of detent 154 and release of pawl 134, so that upon release of the keys, the carriage will correspondingly move one braille cell to the right.

From the foregoing the operation of the device should now be readily understandable. When it is desired to insert a sheet of paper, either key or is depressed, releasing clamping roller from its engagement with collars 84 of platen 40 (FIG. 13B); A sheet of paper is inserted beneath platen 40 and extended under guide bars 34 and 30, over male die 24 and beneath carriage 90, flat under surface 77 meanwhile holding roller 80 in spaced relation to platen 40.

Locating pins 85 are particularly useful in enabling a blind person-properly to align the paper. Release of latch 73 by means of offset end 75 clamps the paper securely in position.

Carriage is now moved to the extreme left of the frame. Selected keys are now simultaneously depressed, and through stems and depending extremities 97 and the engagement of a female die 98 with an aligned male die 24 raises or embosses the appropriate dots or points on the sheet of paper. For example, in forming the braille symbol for the letter J, keys 2, 4, 5 and 6 (FIG. 5) would be simultaneously depressed resulting in the symbol: For the letter C depression of keys 1, 2, 3 and 4 would result in the symbol continuing for each letter of the alphabet. The slot and screw mounting of die plate 24 previously described permits exact alignment of the male and female die portions. As I the keys are depressed, pawl 134 will be released from its engagement with an associated tooth, as previously described, but detent 154 will preclude movement of the carriage (FIG. 6A). Tip 136 will be advanced over the apex of its adjacent tooth by spring 144 to the position shown in FIG. 68. Release of the depressed keys will release detent 154, to the position of FIG. 6, at which time spring reel and cord 123 will move carriage 90 to the right one braille cell until detent tip 136 engages the vertical surface 132 of the next tooth 131. Depression of spacer plate 105 will obviously advance the carriage one space or cell, in the same manner. The lost motion connection afforded by the enlarged head 159 of pin 153 moving in enlarged portion 160 of bore 152 will permit considerable pressure to be exerted on keys 96 without damage to detent 154 or teeth 131.

In the event that a person has one or more fingers missing, individual keys may be depressed and released sequentially, without advancing the carriage, merely by maintaining pressure on spacer plate 105.

When a line of braille symbols has been completed, the paper may be advanced vertically by rotation of knob 47, the engagement of either of ball detents 43 in opening 42 serving as an index to the proper spacing of the lines.

From the foregoing it will now be seenthat there is herein provided a braille typewriter which accomplishes all of the objects of this invention and others, including many advantages of great practical utility and assistance to the blind in rapidly and simply reproducing the characters of the braille alphabet in embossed characters.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiments hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative, and not in a limiting sense.

sponding to a braille point, a toothed rack extending the length of said frame, means including a pawl pivotally mounted on said carriage cooperating with said rack for retaining the carriage in linear position, means on said carriage for advancing the carriage linearly after actuation of the keys, a platen rotatably mounted on said frame, a clamping roller rotatably mounted on said frame contacting said platen for engaging opposite sides of a sheet of paper positioned therebetween with the sheet of paper extending between the die plate and the individual dies for embossing selective points of a braille cell on the paper upon actuation of selected keys, means on said roller for releasably retaining said clamping roller in positions spaced apart, said clamping roller being spring biased into engagement with said platen, and key means for moving said clamping roller out of engagement with said platen, said key means being connected to a link, said link being connected to a pivot roller, said pivot roller in turn being connected to said clamping roller, whereby depressing of said key means moves said clamping roller against its spring bias, latch means for retaining said key means in depressed position, and locating pins at either end ofv said frame adjacent said platen for facilitating the alignment of paper into the device by blind persons.

2. The structure of claim 1 wherein the die plate is linearly adjustable. on said frame to insure accurate alignment thereof with the individual female dies carried by said carriage.

3. The structure of claim 1 wherein the carriage support comprises a pair of spaced parallel bars, and the carriage includes a block provided with aligned grooves engaging said bars.

4. The structure of claim 1 wherein a spacer plate is provided for advancing the carriage independently. of

the actuation of the keys.

5. The structure of claim 4 wherein the spacer plate is moved by depression of the keys, and the pawl is re leased from engagement with the rack by depression of the spacer plate, a spring reel is mounted on the carriage, a cord is carried by the reel and has one end connected to the frame, the means for advancing the carriage including the release of the pawl from engagement with the rack by depression of the spacer-plate and the reel and cord.

6. The structure of claim wherein a detent is carried by the spacer plate, and moved into engagement with the rack upon depression of the keys to release the v pawl, the detent being released by return of the keys to normal, and key return spring means for returning the keys to normal.

7. The structure of claim 6 wherein said detent is normally spring biased into engagement with said rack.

8. The structure of claim 6 wherein a lost motion connector is provided between the detent and the

Claims

1. A braille typewriter comprising in combination a frame, a male die plate carried by said frame having a series of male dies arranged in groups with each group corresponding to a braille cell, a carriage support on said frame, a carriage mounted for linear movement along said carriage support, keys carried by said carriage, key actuated individual female dies carried by said carriage and aligned with an individual male die in one of said groups on said die plate, each die corresponding to a braille point, a toothed rack extending the length of said frame, means including a pawl pivotally mounted on said carriage cooperating with said rack for retaining the carriage in linear position, means on said carriage for advancing the carriage linearly after actuation of the keys, a platen rotatably mounted on said frame, a clamping roller rotatably mounted on said frame contacting said platen for engaging opposite sides of a sheet of paper positioNed therebetween with the sheet of paper extending between the die plate and the individual dies for embossing selective points of a braille cell on the paper upon actuation of selected keys, means on said roller for releasably retaining said clamping roller in positions spaced 180* apart, said clamping roller being spring biased into engagement with said platen, and key means for moving said clamping roller out of engagement with said platen, said key means being connected to a link, said link being connected to a pivot roller, said pivot roller in turn being connected to said clamping roller, whereby depressing of said key means moves said clamping roller against its spring bias, latch means for retaining said key means in depressed position, and locating pins at either end of said frame adjacent said platen for facilitating the alignment of paper into the device by blind persons.

2. The structure of claim 1 wherein the die plate is linearly adjustable on said frame to insure accurate alignment thereof with the individual female dies carried by said carriage.

4. The structure of claim 1 wherein a spacer plate is provided for advancing the carriage independently of the actuation of the keys.

5. The structure of claim 4 wherein the spacer plate is moved by depression of the keys, and the pawl is released from engagement with the rack by depression of the spacer plate, a spring reel is mounted on the carriage, a cord is carried by the reel and has one end connected to the frame, the means for advancing the carriage including the release of the pawl from engagement with the rack by depression of the spacer plate and the reel and cord.

6. The structure of claim 5 wherein a detent is carried by the spacer plate, and moved into engagement with the rack upon depression of the keys to release the pawl, the detent being released by return of the keys to normal, and key return spring means for returning the keys to normal.

8. The structure of claim 6 wherein a lost motion connector is provided between the detent and the spacer plate.

9. The structure of claim 7, wherein the pivotal mounting of the pawl on the carriage includes a slot and pin connection, and spring means urging the pawl in the direction of advance of the carriage, completely to release the pawl from engagement with its adjacent tooth prior to release of the detent.

10. The structure of claim 9 wherein pawl spring means normally urge said pawl into engagement with said rack.