WO2005039882A2

WO2005039882A2 - Keyboard for blind persons

Info

Publication number: WO2005039882A2
Application number: PCT/EP2004/051719
Authority: WO
Inventors: Stefano Scatola; Ermanno Marchesi; Anna Rudari
Original assignee: Appunto R & D Srl
Current assignee: Appunto R & D Srl
Priority date: 2003-10-15
Filing date: 2004-08-05
Publication date: 2005-05-06
Anticipated expiration: 2006-04-15
Also published as: EP1680731A2; ITMI20031989A1; WO2005039882A3

Abstract

Keyboard for blind persons ABSTRACT A composite key comprises: - an external push button (1) on which there is an upper surface (16) that can be pressed with a finger and in which there is an opening (15); - an internal push button (3) that slides inside the external push button (1) and itself comprising a protruding pin (11); - a spring-release mechanism allowing the protruding pin (11) to pass from a first stable position, in which it is retracted and does not protrude from the surface (16), to a second stable position in which the pin protrudes through the opening (15); according to the invention the opening and the protruding pin are placed in an eccentric position compared with the upper surface (16) in order to facilitate the reading of a Braille character which is written using a matrix composed of several composite keys. In this way it is possible to manufacture keyboards to teach Braille writing.

Description

Keyboard for blind persons Field of the invention

The present invention relates to a keyboard for blind persons with which a blind person can write, read and, if required, draw and carry out mathematical calculations. State of the Art

According to Italian patent no. 1193005 a type of keyboard is known with which a user or a sight-impaired person can write, read and carry out arithmetical calculations in the Braille alphabet. This keyboard consists of several basic modules, in this description also called "cells" - consisting of four or six small keys that are arranged on a surface aligned in a matrix at right angles.

Each small key comprises a square key, bored through, into which the small key can disappear or from which a tactile indicator -i.e. a smaller, usually cylindrical, button- can protrude.

Each tactile indicator can be retracted or made to protrude from its square key by means of a mechanism that is similar to that of retractable pens. A tactile indicator protruding from its square key corresponds to a dot of a character in the Braille alphabet, while a tactile indicator that does not protrude from its square key corresponds to a blan k zone of a Braille character.

A user can write a Braille character on the keyboard by pressing or by making the four or six small keys of a cell protrude in the appropriate way. Keyboards of this kind s can be used in schools to teach blind or sight-impaired children to read and to write or they can be used by any blind person to make notes.

In such a mechanical keyboard, as has been manufactured till now, the tactile indicators have been manufactured as cylindrical pins with a relatively large diameter, of approximately 3-3.5 mm; in addition, each of these cylindrical pins is arranged in the centre of its square key or - more precisely, in the centre of the flat surface from which the pin protrudes at one end of each square key; in some ways that is a positive aspect, but in others it has some disadvantages: the cells in fact - especially those with six small keys - have rather large dimensions and that, as well as the arrangement of the tactile indicators in the centre of the square keys, brings about a slowing down during the reading since the reader - especially a reader with small fingers such as a child or a woman - must move his or her fingertip over the cell in order to feel all of it and to read it correctly. The aim of the present invention is to provide an improvement to a keyboard for blind persons according to the state of art, and especially with reference to the disadvantages explained above. Summary of the invention

According to a first aspect of the present invention, this aim is achieved by means of a composite key for the manufacture of keyboards for reading and writing Braille characters, the said key comprising:

- an external push button comprising at one of its ends, suitable for being pressed by the user with a finger, an upper surface, in which there is an opening ; - an internal push button that slides inside the said external push button and that comprises a protruding pin suitable for protruding from said surface through said opening;

- a release system that, after a first press of the said external push button and/or of the said internal push button, is suitable for allowing said protruding pin to move from a first stable position in which the protruding pin protrudes from said upper surface through the said opening, and after a second press, from said second stable position to said stable first position; in said composite key the opening and the protruding pin are placed substantially in an eccentric position with respect to said surface. According to a second aspect of the present invention, the aim explained above is achieved by means of a module of Braille characters for the manufacture of keyboards for reading and writing Braille characters, said module comprising a plurality of composite keys, as defined above, aligned along two directions of the space in order to form a matrix grouping; in this module the parts of the edges of the said upper surfaces that are closer to said openings substantially in an eccentric position, are substantially oriented towards the centre of the matrix grouping. According to a third aspect of the present invention, the aim explained above is achieved by means of a keyboard for reading and writing Braille characters, comprising a plurality of composite keys, as previously defined.

The advantages that can be attained with the present invention will become more apparent to a man skilled in the art by means of the following detailed description of a particular non-limiting embodiment with reference to the following figures.

List of the figures

Figure 1 shows schematically a top view of a keyboard according to a first specific embodiment of the present invention; Figure 1 A shows schematically a detail of the top view of Figure 1 ;

Figure 2 shows schematically a module, comprising six composite keys of the keyboard of Figure 1 ;

Figure 3 shows schematically a partially sectioned side view of the module of

Figure 2; Figure 4 shows schematically a partially sectioned and exploded side view of some components of the spring-release mechanism of the composite keys of the module of Figure 2;

Figure 5 shows schematically a perspective view of the crank element of a key of the module of Figure 3; Figure 6 shows schematically a side view of an internal push button of a composite key of a keyboard according to a second specific embodiment of the present invention;

Figure 7 shows, schematically and in prospective view, a detail of a cursor of the keyboard of Figure 1. Detailed description

Figure 1 shows schematically a top view of a keyboard for reading and writing

Braille characters according to a specific embodiment of the present invention; this keyboard comprises 112 modules 20 aligned at right angles in order to form a matrix of eight rows and fourteen columns; a single module 20 is schematically shown in Figure 2; it comprises six composite keys, arranged at right angles in three rows and two columns in order to represent alphanumerical Braille characters; without departing from the scope of the present invention, each module 20 can be manufactured as a grouping of four composite keys, positioned in a square arrangement - for example in order to manufacture keyboards for carrying out only arithmetical calculations with numbers written in Braille figures, or as a grouping of eight keys - particularly in the case of Braille keyboards that must interface with processors and logical circuits that operate with a binary system. Figure 3 shows schematically a side view, partially sectioned according to a longitudinal section plane, of the module of Figure 2; Figure 4 shows schematically a side view, partially sectioned and exploded, of some components of the spring- release mechanism of the composite keys of the module of Figures 2 and 3; each composite key comprises:

- an external push-button 1 that, in the present application, has the shape of a hollow body with an approximately cubic form with an open side - the lower one, with reference to the attached Figures - which defines, at its upper end suitable for being pressed, an upper surface 16 that is substantially flat - Figure 4; the flat surface 16 has the function of being perceived to the touch like the "blank" background of a dot - or like the white frame without the dot - of a Braille character;

- an internal push-button, referred to with the general reference 3, that can slide inside the external push-button 1 and that comprises a protruding pin 10. The external push-button 1 and the internal push-button 3 can slide longitudinally in the same sliding direction with respect to the housing 8 - vertically with reference to Figure 3.

In addition, each composite key comprises a spring-release system which, after a first press of the external push-button 1 and/or of the internal push-button 3, make the internal push-button 3 move from a first lowered stable position - in which the protruding pin 11 is in a retracted position with respect to the upper surface 16 without protruding from it -see composite key 21 in Figure 3 - to a second raised stable position, in which the protruding pin comes out through the opening 15 protruding from the upper surface 16 -see composite key 21 A in Figure 3; after a second press of the external push-button 1 and/or of the internal push-button 3 the spring-release mechanism makes the internal push-button 3 change from the second raised stable position to the first lowered stable position. In the present embodiment the spring-release system consists of an analogous mechanism to that which moves and places the sliding cartridge of retractable ballpoint pens with a push-button and which comprises (Figures 3, 4) the upper spring 2 and the lower spring 6, the rotating bush 4 and the lower sliding pin 5. At the lower end of the internal push-button 3 and inside the grooved sliding seat 80 in the housing 8 of the module, there are some grooves in relief of a type known per se and used in some kinds of spring-release retractable pens. By suitably pressing the different external push-buttons 1 and/or of the protruding pins 11 of a module 20, it is possible to form a Braille character where the protruding pins 11 in protruding position compared with the surfaces 16, can be felt like Braille dots, while the pins 11, in retracted position below the surfaces 16 and not protruding from them, are perceived to the touch like a missing dot or a blank zone of a Braille character. Preferably modules 20 and the control mechanisms of the external push-button 1 and of the internal push-button 3 are so manufactured that the upper surfaces 16 are basically copianar with each other, independently of whether the corresponding protruding pins are in the first or in the second stable position - in which they raise from or are retracted to the corresponding upper surfaces 16: this improves the quality of the tactile reading and facilitates the learning of the "blank background" concept of a Braille character for a blind person.

According to a first aspect of the present invention, the opening 15 and the protruding pin 11 are placed in a position which is substantially eccentric with respect to the upper surface 16 and, in the embodiment here described, with respect to the cross sections of the external push-button 1; the expression "substantially eccentric" with respect to the upper surface 16, in the case of a regular polygon-shaped upper surface 16 - especially in the case of a square or equilateral-triangle shape of the surface - and of a rectangle or rhomb shape, means that the hole or the opening 15 and the protruding pin 11 are at a appreciable distance - taking into account tolerances and manufacturing inaccuracies - from the barycentre and from the centre of symmetry of the surface 16 itself (Figures 1 A, 2). This allows the different composite keys that make up each module 20 to be placed so that the protruding pins 11 are closer around the centre of the module, i.e. the different composite keys are oriented so that the edge portions of the upper surfaces 16 that are closer to the openings 15 are substantially turned towards the centre of the matrix grouping of the composite keys of the module - Figures 1 A, 2. By bringing the different protruding pins closer towards the centre of each module 20, the sliding movement with the fingertip on the module to feel the whole Braille character that is written on it is no longer necessary; thereby speeding up the reading of the keyboard and making the characters easier to learn - in fact, the reader must not dedicate attention to the movements of the fingertip in order to feel the whole reading surface of the module.

Preferably the area of each upper surface 6 is at least 4. 5 times bigger than the cross section of the corresponding protruding pin 11. More preferably the area of each upper surface 16 is comprised between about 10 times and about 25 times that of the cross section of the protruding pins 11 ; in the preferred embodiment described here, the area of the different upper surfaces 16 is about 25 times larger than the section of the different protruding pins, each protruding pin 11 has a circular section with a diameter of about 1.5 mm and the upper surface 16 is approximately a square surface with a side of 6.5 - 7 mm. These dimensional ratios contribute further to avoiding the user having to feel with the fingertip each module in order to perceive correctly the whole Braille character. The use of protruding pins of a relatively much smaller diameter compared with the upper surfaces 16 or with the cross sections of the external push-buttons 1, makes furthermore more interesting the manufacture of keyboards with eight composite keys each - i.e., modules that are able to reproduce "eight-dot" Braille characters - which are particularly suitable for the manufacturing of Braille interfaces with computers and, generally, with calculation machines that operate using a binary logic - each eight-dot module can reproduce a "byte" - and for carrying out algebraic calculations and complex mathematical operations in Braille: in fact, in the known six-dot Braille characters the numbers, the mathematical operators and the algebraic expressions are written using the same characters as the Braille letters, but preceded by other signs, "number indicators"; the eight-dot Braille characters allow the reproduction of numbers, mathematical operators and algebraic expressions that are easier both to write and read. In the preferred embodiment seen in Figures 3 - 5, the intemal push-button comprises an internal cursor 3A and a crank element 10 that in turn comprises: - a disc-shaped body 12;

- a fixing pin 13 that is provided on the lower side of the disc-shaped body 12;

- a protruding pin 11 that is provided on the upper side of the disc-shaped body 12. The fixing pin 13 is inserted in a corresponding seat 14 (Figure 4) that is made on the upper end of the internal cursor 3A; the protruding pin 11 and the fixing pin 13 are parallel, but not coaxial in order to create a crank when the crank element is inserted in the seat 14.

In the embodiment seen in Figure 3, preferably when the protruding pin 11 is in a retracted position and not in a protruding position with respect to the upper surface 16, it is however, at least partly, inserted in the hole 15 in order to be still aligned with the hole if the crank element 10 can freely rotate in the seat 14.

Making the internal push-button 3 with two separate elements 10 and 3A is particularly advantageous for assembling the composite keys 21, 21 A when the latter are controlled by a spring-release mechanism like the known one used in ballpoint retractable pens with a push-button: in fact, in these spring-release mechanisms the internal cursor 3A has an external grooved surface 30A that fits against a grooved seat 80 in which the cursor slides, therefore the internal cursor 3A can not rotate freely on itself within the grooved seat 80, but can only take on a limited number of fixed angular positions with respect to that seat, except limited rotations that are allowed by the play of the grooved coupling. When the internal push-button 3 is manufactured with two separate elements 10 and 3A, the alignment of the various protruding pins 11 with the holes 15 that are in different positions on the surfaces 16 according to the position of the corresponding composite key in a module 20 - see Figure 1A - takes place by simply rotating the crank element in seat 14 instead of looking for the most opportune angular position of the intemal cursor 3A compared with the grooved seat 80 within which the cursor slides. According to the alternative embodiment of Figure 6, the internal push-button 3' does not comprise the crank element 10 and the protruding pin 11 is integral with the internal push-button 3': this reduces the number of pieces to be assembled, but requires an adequate orientation of the grooved seats 80 and of the grooved surfaces 30A of the different composite keys of a module 20.

Advantageously, both in the embodiment of Figures 3 - 5 and in the one of Figure 6, the openings 15 are small enough so as to allow pressing the intemal pushbuttons 3, 3A by pressing with only one finger the external push-button 1 instead of pressing directly on the protruding pin 11: the present invention makes writing with a keyboard faster.

Advantageously, the keyboard of the embodiment of Figure 1 , has one or more projecting parts or rectilinear ribs 22, specifically two projecting parts or rectilinear ribs that are parallel to each other and positioned respectively between the first and second row and between the sixth and seventh row (this means between the first and second row on one side and between the last but two and the last but one row on the opposite side), parallel to the direction of the rows or of the columns made up of the different modules 20 that are placed in a matrix way on the keyboard: these projecting parts or rectilinear ribs 22 help the user to differentiate to the touch the row of the result of an addition or of a subtraction from the rows of the addenda or of the subtraction factors.

For example, although not necessarily, the projecting parts or rectilinear ribs 22 are fixed on the keyboard so that they cannot be moved. More generally, if the modules are positioned on a keyboard in an aligned way, but not at right angles to each other, but according to two generic directions - i.e., arranged in a matrix with a non-right-angled network - the projecting parts or the rectilinear ribs 22 will themselves be oriented at right angles - in the embodiment here described, the projecting parts 22 are oriented parallel to the longest side of the keyboard. Advantageously, movable cursors 23 (Figures 1, 7) can slide on all ribs or rectilinear projecting parts 22 or on some of them and serve the purpose of making it easier for the user to recognize the columns of the units, tens, hundreds and of the other powers of ten - whether positive or negative - of the numbers put in columns in order to carry out a multiplication or a division; in the embodiment shown in Figure 1, on each cursor 23 the columns are identified by means of vertical signs I, II, III - that are obtained as ribs in relief or hollowed notches - each of them can be associated to a different column; the different columns can obviously be identified by applying different signs or markings on each cursor 23. The movable cursors 23 and the markings applied on them in order to differentiate the columns are useful to carry out calculations and arithmetical operations by setting the Braille figures on the keyboard in rows and columns, similarly to what a sighted person does when he carries out arithmetical calculations - for example, the four basic arithmetical operations, addition, subtraction, multiplication and division - using paper and pen.

The embodiment just described can be modified in a number of ways, all without departing from the scope of the present invention. A further embodiment of the present invention concerns a keyboard for the reading and writing of Braille characters, similar to that shown in Figure 1 and comprising several composite keys, each comprising

- an external push-button 1 comprising, at one of the ends intended to be pressed by the user, with a finger, an upper surface 16, normally flat, in which there is an opening 15'; - an intemal push-button 3 that can slide inside the external push-button and that comprises a protruding pin 11' intended to protrude through the opening 15' compared with the upper surface 16;

- a release system that, after a first press of the external push-button 1 and/or of the internal push-button 3, allows the protruding pin 11' to move from a first stable position, in which the protruding pin is in a retracted position compared with the upper surface 16 without protruding from it, to a second lifted stable position, in which the protruding pin 11' comes out from the upper surface 16 through the opening 15 and, after a second pressing, from the said second stable position to the first stable position; these composite keys are grouped in modules, in each of which the composite keys are aligned in two dimensions in order to form a matrix grouping; the different modules are aligned on the keyboard in two directions of the space in order to form a second type of matrix grouping; this keyboard comprising furthermore

- at least a projecting part or rib 22' that is inserted between two parallel rows and is oriented in one of the above mentioned predetermined dimensions;

- one or two slide cursors 23 that can slide on each of the projecting parts or rectilinear ribs 22', and that are suitable for being positioned by predetermined columns of modules, where each of these columns is placed at right angles to the projection parts 22' so that the user can distinguish more easily the different columns of the module matrix of the keyboard; in this embodiment the protruding pins 11 ' are not placed on the upper surface 16' in an eccentric position, but they are in the center of it. Any change or modification that does not depart from the scope of the invention as defined in the claims is to be intended as included in the present invention.

Claims

1) Composite key for the manufacture of keyboards for reading and writing Braille characters, said key comprising:

- an external push-button comprising at one of its ends, suitable for being pressed by the user with a finger, an upper surface, in which there is an opening ;

- an internal push-button that can slide inside said extemal push-button and that comprises a protruding pin suitable for protruding from said surface through said opening;

- a release system that, after a first press of said external push-button and/or of said internal push-button, is suitable for allowing said protruding pin to move from a first stable position in which said protruding pin is retracted and does not protrude from the said upper surface, to a second stable position in which said protruding pin protrudes from said upper surface through said opening and, after a second press, from said second stable position to said first stable position; wherein said opening and said protruding pin are placed substantially in an eccentric position with respect to said upper surface.

2) Key according to Claim 1, wherein said external push-button has a cross section that is at least 4.5 times greater than the cross section of said protruding pin. 3) Key according to Claim 2, wherein said external key has a cross section that is comprised between about 10 times and about 25 times the cross section of said protruding pin.

4) Key according to one or more Claims from 1 to 3, wherein said internal pushbutton comprises a) an internal cursor that can slide in the sliding direction of said external and internal push-buttons; b) a crank element comprising said protruding pin and that is fixed to said internal cursor so that said protruding pin can rotate around an axis, said protruding pin being in an eccentric position with respect to said axis so as to allow relative displacement of the protruding pin with respect to said upper surface at least in directions that are parallel to the upper surface. 5) Key according to Claim 4, wherein the end of said external push-button, that delimits said upper surface, is suitable for being pressed against said crank element when said external push-button is pressed so that said crank element and said intemal cursor are both pressed. 6) Key according to one or more previous claims, further comprising an electric or electronic interface that can send electric signals which can be associated to the condition in which said protruding pin raises from said upper surface and to the condition in which said protruding pin is retracted inside said external push-button and does not protrude from said upper surface. 7) Module of Braille character for the manufacture of keyboards for reading and writing Braille characters, said module comprising a plurality of composite keys according to one ore more previous claims that are aligned along two directions of the space in order to form a matrix grouping, wherein the portions of the edges of said upper surfaces, that are closer to said openings substantially in an eccentric position, are substantially oriented towards the centre of said matrix grouping.

8) Module according to Claim 7, comprising at least eight composite keys according to one or more previous claims.

9) Keyboard for reading and writing Braille characters, comprising a plurality of keys according to one or more claims from 1 to 6. 10) Keyboard for reading and writing Braille characters, comprising a plurality of modules according to Claims 7 or 8.

11) Keyboard according to Claim 10, wherein said modules are positioned in a matrix way on said keyboard, aligned in two directions of the space.

12) Keyboard according to Claim 11 , comprising at least one projecting part or rib, inserted between two parallel rows of said modules and oriented in one of said predetermined directions.

13) Keyboard according to Claim 12, comprising at least a first and a second said projecting part or rib that is positioned in one of said predetermined directions of the space, wherein said first projecting part or rectilinear rib is positioned between the first and the second row of said modules from one edge of said keyboard and said second projecting part or rectilinear rib is positioned between the last but one and the last but two row of said modules from a second edge of said keyboard opposite to said first edge, said rows of modules being considered parallel to said first and second projecting parts or rectilinear ribs.

14) Keyboard according to Claims 12 and/or 13, comprising one or more sliding cursors that can slide on each of said projecting parts or rectilinear ribs and that are suitable for being positioned by predetermined columns of said modules, each of said columns being positioned at right angles to said projecting parts or ribs so that they can help the user to distinguish the different columns of the matrix of modules on the keyboard.

15) Keyboard for reading and writing Braille characters, comprising a plurality of composite keys, each of which comprises

- an external push-button comprising at one of its ends, suitable for being pressed by the user with a finger, an upper surface, substantially flat, in which there is an opening ;

- an internal push-button that can slide inside said external push-button and comprising a protruding pin that can protrude from said surface through said opening;

- a release system that, after a first press of said external push-button and/or of said internal push-button, make said protruding pin move from a first stable position in which said protruding pin is retracted and does not protrude from said upper surface to a second stable position in which said protruding pin protrudes from said upper surface through said opening and, after a second press, from said second stable position to said first stable position; wherein said composite keys are grouped in modules, in each of them said composite keys are aligned according two directions of the space in order to form a matrix grouping, said modules being aligned on said keyboard, at right angles in order to form a matrix grouping; said keyboard further comprising

- at least one projecting part or rib that is positioned between two parallel rows of said modules and is oriented according to one of said predetermined dimensions; - one or more sliding cursors on each of said projecting parts or rectilinear ribs that can be positioned by predetermined columns of said modules, each of said columns being positioned at right angles to said projecting parts or ribs, so that they can help the user to distinguish the different columns of the matrix of the modules on the keyboard.