GB2356730A - Letters of alphabet formed from hingedly connected sections - Google Patents

Description

I Hinge System 2356730 This invention relates to a mechanism for

articulating the components of certain letters which form part of an Arabic alphabet teaching aid. The general concept of the teaching aid is described in GB 2244842.

The Arabic alphabet has 28 letters, each of which can have a leading, medial, terminal or detached character form depending on which position in a word the letter adopts. Some characters may be the same irrespective of position, some may have two different forms, others may take a distinct character form io in each of the four roles. There are also certain rules dictating which letters may or may not be placed next to others. GB 2244842 describes a method by which some of the characters of an alphabet may be represented by respective first components (e.g. of rigid plastic) and the remaining characters can be formed from these first components, by articulating sections of the first components and/or by adding extra components to the first components. The components may have formations (e.g. recesses) permitting correct linking of the components/characters.

Herein is described a hinge system and method of manufacture by which the sections of a letter may be pivoted to form an alternative character in dependence on the position of the letter in a word.

The hinged elements are moulded integrally with the letter elements themselves. Each hinge comprises a "male" and "female" element which are moulded integrally into the elements which are hinged together. Such integral design reduces the complexity of manufacture and hence keeps down the cost of assembly. This design also allows component pieces to be sold 2 unassembled and hence self assembly is possible. These elements must therefore be easy to assemble by hand. Such an integral hinge design also permits the disassembly of the letter into its component parts by the user in order to construct un-envisaged shapes with the letter components. A permanently fixed hinge incapable of disassembly would have prohibited this versatility which allows an important secondary mode of play. Although it is important that the components are able to be disassembled, it is also important that these elements remain firmly attached during use once io they have been connected together. The letter character formed by the combination of two or more elements is to be used to teach a letter character and clearly, if it disassembles too easily into its constituent parts it would fail to fulfil its function. The fabrication of a hinge which does not disassemble easily is complicated by the necessity for the "male" element of the hinge to escape from the tool during the moulding process. A further element incorporated in the hinge is a mechanism for locating two elements of a letter when the two elements rotate into the correct position in relation to each other. This location is accompanied by a positive "snap" or "click" or both. This snapping and/or clicking into position serves as a means of indicating that a given orientation of the two hinged elements is correct for one of the character forms of that letter.

Embodiments of the invention will now be described with reference to the accompanying drawings.

Figure 1 Schematic illustration of the two parts of a character bearing "male" and "female" hinge elements.

3 Figure 2 Schematic diagram of a cross section of "male" element.

Figure 3 Schematic diagram of a cross section "female" element.

Figure 4 Plan view of a "male" element.

Figure 5 Cross sectional view of one half of a tool for making a "male" element holding component of a letter.

Figure 6 Cross sectional view of an insert for forming the main axle members of the "male" element.

Figure 7 Perspective view of the letter "Ha" in a particular position Figure 8 Perspective view of the letter "Kaf" in an end of word form.

The "female" half of the hinge is necessarily similar in shape to the tooling which is used to produce the "male" half. This means that a compromise must be found between the "male" element tending to escape the "female" connection once the components are assembled and not being able to remove the "male" element from the tooling. A profile for a "male clip" 1 is shown in figure 1, which has sufficient stiffness to hold the assembled hinge together and which can also escape from a tool without being unduly deformed or breaking off altogether. Any breaking within the tool is obviously highly undesirable during the commercial production of the components.

Figures 2 and 3 show a detail of the "male" and"female" elements respectively. In figure 2 the main axle 4 of the "male" element is shown which is formed with a catch 5 at the terminus of each. The catch 5 has an operative underside slope 6 which acts against slope 7 of the "female" element, shown in figure 3. The main axle 4 is of a smaller diameter than a bush 8 allowing the "male" element to rotate within the"fernale" element.

4 Withdrawal of the "male" element is possible only when sufficient force is applied in the axial direction and bend the main axle members 4 inwards as slope 6 to moves over slope 7. Opposing this action is a reaction provided by the resilient nature of the axle 4 material and the sleeve 14. Eventually the main axle members 4 will compress enough to allow the catches 5 to slip through the bush 8. A rim 10 is provided at the base of the "female" element which locates with a recess 9 provided at the base of the main axle member 4 of the "male" element, which acts to stabilise the joint when the elements are connected.

For the production of the letter components, a simple two part tool was chosen in order to keep tool manufacturing and production costs low. By two part is meant a tool which is essentially in two halves. Each half being mounted on opposite faces of a simple moulding machine. It will be appreciated that each half in itself can be formed of one or more component parts. Figure 5 shows one half of the tool used for the production of "male" element bearing components of letters. It is important that a user is assured of the correct orientation of the components 3 of a character. This is facilitated by the provision of a "click" as the correct orientation is located.. This clicking mechanism must give a firm indication that the correct position has been arrived at, and yet it must not be so firm as to prevent the hinge from being easily rotated to its next correct position. This locking mechanism requires a ridge 11 and groove 12 mechanism, as illustrated in figures 3 and 4, moulded into the moving surfaces between the male and female halves of the hinge. This ridge 11 and groove 12 forms part of the snapping and/or clicking element. When the hinge is rotated out of a "correct" position the main axle members 4 of the &&rnale" clip are forced together when the two components separate as the ridge 11 is forced out of its corresponding groove 12. The main axle members 4 of the "male" clip are thus put under tension as the "male" clip is pulled up and partially out of the "female" half of the hinge and act to snap the two components back together when the new locating groove 15 is reached. The "male" clip is raised out of the "female" half during rotation between correct positions which causes the hinge to partially disassemble leaving it very vulnerable to dissociation with only the slightest of force. The ratio of the io slopes 6 and 7 is therefore critical. Furthermore the ridge and groove of this mechanism is designed to be durable under repeated opening of the hinge. The "male" clip must also be strong enough to not to fatigue with repeated usage and to provide sufficient force to snap the hinge shut in the "correct" positions.

It will be appreciated that when the ridge 11 comes into contact with the end of the groove 12, the end of the groove will act as a stop and prevent the components 3 from rotating relative to each other any further than desired. Alternatively, if a shallow groove is provided, the components 3 may rotate through 360 degrees only offering a click when the ridge and groove correspond. The characters are also adapted to permit a preceding character to link with it. Every character of the 28 letter alphabet is adapted with a square-sectioned plug located at the back of the letter. This plug is positioned such that a square sectioned hole of a preceding letter is able to link with it with an interference fit. The square-sectioned hole is open at its furthest end. In this 6 way two letters can be joined together either by sliding them together when they are both on a flat surface, or the letter being joined to a previous letter can be placed from above into the correct position. Naturally any combination between these two approaches is also possible. The square-sectioned hole has two thin walls at either side of the open end and these walls join the main body of the letter which forms the third closed section of the square-sectioned hole. The hole is not open but closed at the bottom. With this design of linkage the square-sectioned hole can be represented as a "hand". Each of the walls forming a "finger"with three more "fingers" represented on the bottom of the square-shaped hole. Having the bottom of the square-shaped hole covered also gives extra strength to the walls and produces a more easily controllable interference fit. The linkage between two letters is an interference fit enabling the letters to be linked one to the next from above in the order of writing the Arabic letters and is universally the same between all of the letters so that any of the 28 letter character set could be joined to by any other character adapted to do so. The linkage between two letters is such that the two or more characters joined together can be lifted and moved without coming apart readily- yet at the same time the interference should be such that the letters can be readily disassociated with little force. A very important instance of linking occurs with the letter "Ha" in its medial and final-joining form. The same linkage point must be used on this letter in two instances which are 90 degrees to each other. This requires a linking system which can work equally well when rotated through 90 degrees. Such a linkage is shown in figure 7.

7 The design of the linking mechanism for the character forms of the letter "Kaf" is worthy of mention. The characters of this letter are composed of four elements. Two of these elements must be adapted in such a way as to present a "hand" linkage point when in the open position. The same two elements must however also be adapted such that they can fit exactly over each other such that the "hand" closing off access to the square-sectioned plug when the hinge is rotated to the closed position, i.e. through 180 degrees to the open position. The plug is the same distance from the hinge on the one element as the "hand" is from the hinge on the other element. This folding io back of one element completely under the other is required not only to achieve the correct character shape, but also to close off the plug on the element in question. This prevents a previous letter being incorrectly joined from this plug when the letter is in this character position. There is a second plug on this letter which becomes accessible for joining once the character is changed to its correct new position with the old plug. Furthermore it is not only the one plug that needs to be made inaccessible. The hand which covers the plug must also become inaccessible. The reason for this is that in teaching the letters one uses the rule that a letter, if it has a hand, when at the end of a letter holds on to a tail. In the case of the letter "Kafthe letter at the end of a word does have an open hand. This letter however changes its shape to look as if it has a tail. In order to do this it must hide away its hand in the way described above. The solution to this rather exacting problem takes the following into account. The two elements must be adapted to come together under a rotational movement. This is problematic as the two elements rotating together should under normal circumstances be forming a 8 linkage and the raised wall of the "hand" on one element would bump into the plug on the other element thus preventing the elements sliding one over the other. There is also another difficulty. The now overlapped hand and plug element must be prevented from locking together in the usual way thus preventing them from being disconnected by a similar rotational movement which brought them into contact. These two elements should exhibit the same "click" which would indicate that a correct position has been arrived at when the two elements slide over each other.

io Most importantly any modification to this linkage to adapt it for the particular needs of this letter must bear in mind that the character formed with the two elements in the extended position (i.e. the character of "KaF which does not have the "harnza") must be able to link to another similar character. The solution to this problem has the wall height on one side of the "hand" of the "KaF reduced by almost one half. This half wall height still allows this letter to connect to any other letter effectively. This wall, however has a slot cut into it near the main body of the letter. The normal wall is thus not only reduced in height by approximately one half but also half of its length is also reduced. Despite this it is still able to hold other letters effectively by their plugs. The slot cut into the main body of the letter allows the corresponding plug on the other element under which it must slide to have at least part of its plug the standard length the rest of the plug must be partially cut away to allow the half length wall to clear past it. Were it not for the fact that this character must be able to link to a similar character when the hinge is open i.e. with the hand showing), one could have reduced the plug to half its usual 9 length and reduced the height of the wall to half its usual height. In this case however two letter "Kaf"s would not have been able to link to each other. With the solution described there is just enough plastic in the wall of the hand to be able to locate against the fully extended plug section of a similar character to make for a satisfactory interference fit between two letter "Kaf"s. The wall and plug respectively are not reduced quite by one half, as advantage can be taken of slightly shaping the plastic at the points of contact between the two elements as they come together just before they overlap. Such shaping causes one element to ride over the other and therefore provide a lock to io keep them in a closed position. Once in place, similar slight shaping allows the elements to ride over each other in the reverse direction. Finally by incorporating a raised and curved section of plastic at the front edge of the plug (that part which has been cut back to approximately half height) the element which has to slide under the other is forced to flex away from the element which has the plug when the two elements are sliding over each other. This places a tension between the two elements which is released once the two elements come to their final positions. This then serves to accentuate the feeling of the snapping and clicking into the correct position. An important point to realise is that the design of the hinge and the linkage are not independent since in certain instances the plug of the letter falls in exactly the same position as the hinge. This occurs more than once. It happens in the case of the "Lam", the "Oaf" and the "Nun". It also occurs in two instances on the "Kaf". This forms a very severe restriction on the hinge dimensions which must fit within the square plug of the linkage system.

Figure 8 shows the structure of the letter "Kaf".

The letters are adapted in such a way as to permit the insertion of a suitable magnet into the back of the letter to permit it to be used in conjunction with a metal or magnetic board. The linkage is represented as a "hand" so as to tie in with the accompanying 5 picture books and stories explaining the usage of the letters in terms of "hands" and "tails" for the letters. A non toxic / child-safe, firm and durable plastic may be used to fabricate the components. Acetyl is a preferable type of plastic although a range of other plastics could also be used. Acetyl has the advantage of being of low cost.

The plastic must be strong and durable and also sufficiently elastic for the hinge mechanism to work effectively and repeatedly. Each letter at its widest point is typically 8mm. This means that a hinge is small. A larger hinge would require larger letters. Considerations such as a comfortable size for children's hands has played a part in selecting the size of the letters and they do not form too bulky a mass when a full working set of letter components are together. Their size is of particular importance as a long word or short phrase can be written with these letters on an A5 sheet of paper. This fact is important for the design of accompanying picture books showing template words life size on the page. A hinge had to be designed which was capable of working effectively at this size. By way of explanation as to why larger letters would be relatively easy to produce it should be said that there are various industry standard devices which can be used in a two part mould which can effectively release the part of the "male" clip which is likely to be deformed or break off in the tool. These devices however can not be easily accommodated in a small tool.

Claims (10)

1 A hinge system for pivoting a section of a letter of an alphabet, each letter comprising at least one letter element, and the hinge system comprising: a male member and a female member; each member being integrally formed with the letter element that each is associated with; whereby the male member and female member are engagable with each other such that a section of the letter may be pivoted to form an alternative character form of the letter dependent on the position of the letter in a word.

2. A hinge system as claimed in claim 1 for use with the Arabic alphabet.

3. A hinge system as claimed in claim I or 2 wherein the hinge system is capable of being disassembled.

4. A hinge system as claimed in any one of claims 1 to 3 wherein the male member comprises: an axle protruding from the letter element with which it is integrally moulded; a sleeve mountable over the axle; a plurality of catches formed at the terminus of the male member and extending from the axle, each catch having an operative underside slope; and a recess formed around the perimeter of the area where the axle protrudes from the letter element; and the female member comprises: a shaft having a diameter which is larger at its innermost portion; an operative slope connecting the two diameters of the shaft and which acts against the underside slope of the corresponding male member when the respective letter elements of the male member and the female member are hinged together; and a rim 12 formed around the periphery of the open end of the shaft which, in use, locates with the recess of the male member.

5. A hinge system as claimed in any one of claims 1 to 4, wherein the hinge system further comprises location means for locating the letter elements when the two letter elements rotate, with respect to each other, into an orientation that is a correct position for one of the character forms of the letter.

6. A hinge system as claimed in any one of claim 1 to 5, wherein the location means is a clicking mechanism that sounds a click when the letter elements have rotated into the correct position.

7. A hinge system as claimed in claim 6 wherein the clicking mechanism comprises; at one groove formed in one of the letter elements to be hinged; and at least one ridge formed on the other letter element to be hinged, and adapted to fit into the groove on rotation of the letter elements into one of the correct positions.

8. A hinge system as claimed in any one of claims 1 to 7 wherein the male member and the female member are each integrally moulded with the letter element that each is associated with.

9. A hinge system substantially as hereinbefore described with reference to the figures 1, 2, 3, 4, 6, 7 or 8.

10. A method for producing the male member of a hinge system as claimed in anyone of the preceding claims from a two-part tool, comprising the steps of:

mounting each half of the tool on opposing faces of a moulding machine; 13 locating correct orientation of each half of the tool on the moulding machine; introducing liquid material into the moulding machine for forming the male member from the tool; cooling the tool; characterised in that the two-part tool has a slideable shaft member and the method comprising the further step of extracting the formed male member from the tool by sliding the slideable shaft member of the tool against the catches of the male member which contracts the male member to a diameter small enough for removal from the tool.