MXPA97008889A - An alfanumer keyboard - Google Patents

Abstract

The present invention relates to an alphanumeric keyboard (1) that includes a plurality of numeric function keys. According to the invention, the keyboard (1) is programmed in such a way that the alpha letter is always generated when two mutually adjacent keys (T) are pressed simultaneously, and that a number is generated when only one numeric key is pressed.

Description

AN ALFANUMERICG KEYBOARD The present invention relates to an alphanumeric keyboard that includes a plurality of numeric keys and keys for functions. The invention can be applied primarily to limited size keyboards having a limited number of keys and then, particularly with keyboards for laptops and mobile phones.

A number of alphanumeric keys operating with a numerical method and with an alphabetic method when the appropriate keys are pressed are known in the art; see, for example, United States Patents US-A-4 549 279, US-A4 994 992, US-A-5 117 455 and US-A-5 339 358 in this regard. The first two US patent specifications mentioned above also show a keyboard in which up to four adjacent keys are pressed simultaneously to create as many functions as possible with as few keys as possible. Although a keyboard with this construction is compact, it is also difficult to grasp, that is, it is not easily handled and not with a particularly friendly user. The last two specifications of the aforementioned US patents report keyboards on two of the mutually adjacent key pairs that are used to generate certain letters or characters or alpha letters when the keys of the pairs are pressed one after the other .

The aim of the present invention is to provide an alphanumeric keyboard of limited size and having a limited number of keys which is both user-friendly and which will allow the numeric and alpha characters to be generated alternatively by pressing one or more keys with a single finger of a hand and without using a capital key. According to the invention, these objectives are achieved with an alphanumeric keyboard of the aforementioned type, which is characterized in that the key is programmed in such a way that when two mutually adjacent keys are simultaneously pressed, an alpha letter will always be generated, while A number will always be generated when only one numeric key is pressed. Because the numbers are always generated by pressing only a single key and the letters are generated by pressing two adjacent keys simultaneously at the same time; It will be very easy for the user to be able to separate these functions that contain both numbers and letters or alpha characters.

Because the keys are separated from one another, there is also less risk of the user unintentionally pressing two adjacent keys simultaneously.

According to a preferred embodiment of the invention, the numeric and alpha characters are generated when a single key or two keys return from a depressed position, and where the oppression of a key will activate the search means, or means of scrutiny, the that investigates whether an adjacent key was pressed more than a given time duration.

Now the invention will be described in more detail with reference to the accompanying drawings, wherein: Figure 1 is a front view of a portable computer that is provided with a keyboard in accordance with one of the embodiments of the invention; And Figure 2 is a front view of a portable computer that is provided with a keypad in accordance with one embodiment of the invention, and Figure 2 schematically illustrates an example of a signal development when two keys are pressed simultaneously.

The laptop illustrated in Figure 1 includes an inventive key 1. The keyboard includes twenty T-keys that are mutually spaced in seven rows and three columns. The top ten keys in Figure 1 are numeric keys, where the ten remaining keys are operation keys. The T keys are shown as round rings in the figure and conventionally marked with the number that is generated for the function that takes place when the key in question is pressed. The letters A-0 are printed on the keyboard 2 in the spaces between the adjacent keys in the rows and columns.

The keyboard 1 is programmed in such a way that when two adjacent keys are pressed together a letter will be generated. So when the keys 7 and 8 are pressed simultaneously, the letter A will be generated, while the simultaneous oppression of the number keys 7 and 4 will generate the letter C. Because the letters or alpha characters are always generated when they are pressed simultaneously two adjacent keys, a user can learn to use the keyboard very quickly since once he has good knowledge of the key there is almost no risk of the user using the keys wrongly. In addition, an alphanumeric expression can be typed without using the SHIFT key and only pressing one or two keys for each of the characters that will be generated, and with this allowing the expressions to be written quickly and with the same positive degree that when only numeric expressions are written. Because the pairs of the keys that generate the letters comprise two mutually adjacent keys, they can be pressed simultaneously with only one finger, taking into account of course that the keys are not widely spaced.

The laptop illustrated in Figure 1 is built to facilitate the writing of alphanumeric characters with the help of the thumb of the same hand that holds the computer. In order to facilitate this, the keys are preferably not placed very close together, since this makes it very difficult to press only one key and with this increase the risk of unintentionally pressing the two keys simultaneously.

In this document, the simultaneous oppression of two adjacent keys means that the two keys are pressed by virtue of the continuous movement of the finger. In this movement, it is not unusual for the finger used to momentarily touch a key before touching another key and the oppression of the two keys does not actually occur at the same point at the same time precisely. Figure 2 schematically illustrates the voltage V as a function of time t with respect to the keys Ti and T2, for example the keys of the numbers 1 and 2, the oppression of these keys generate a letter, for example the letter K. the keys TI, T2 are pressed at the time point ti and t2 respectively, the voltage will fall from the value VI to the value V2, and from the value V4 to the value V3 respectively, and when the keys are released at the respective time points t4 and t3, the voltage will increase in the respective values VI and V4. In the case illustrated, the user's finger first touches the TI key and a little later touches the T2 key, while the TI, T2 keys are released at virtually the same time.

In order to establish if the oppression of the key is related or not to an alpha letter, a key search program starts each time a key is set, that is, the voltage drops to its background value, where at least the adjacent keys of the key pressed are investigated for a given period of time in order to establish whether one of the keys has been pressed or not. If no other key has been set during the search period, the number or function of the key pressed is stored, and when the key is released the stored letter is written, that is, when the voltage returns to its previous values. On the other hand, if one of the keys adjacent to the pressed key is also pressed within the search period, a letter is stored and written when the keys are released. The program ignores the oppression of another key after finishing the period of the search. The search is interrupted when the oppression of another key is detected.

So, in order to press the TI, T2 keys to result in a letter being written, as illustrated in Figure 2, the search period must have a length of time that is equal to or greater than the time difference tl-t2. It has been found that this time difference will conveniently be within the range of 10-500 ms (thousandths of a second), preferably in the range of 50-200 ms.

It is also possible to schedule a runtime to write a letter some time after the search has been interrupted, either because the time period ended or because it was detected that another key was pressed.

This means that the letter will be written after a given period of time has ended, regardless of whether the key or keys have been released or not. It is also possible to prescribe that the key or keys should be pressed for a given period of time before the letter is written.

The laptop shown in Figure 1 includes a display 3 and a series of operation keys Fl-Fß. If you wish to extend the number of functions without increasing the number of keys, it is certainly possible to use other combinations of keys in addition to the ones described above in order to program these functions and adapt the search installation according to the case.

As will be understood, the described embodiment of the keyboard can be modified within the scope of the invention. For example, the configuration of the keyboard and the placement of the key may be different from what was shown. For example, the keyboard can be circular and the keys are placed in circles concentrically. The keyboard can also be programmed, so that the numbers are written when the T key is released from its depressed seat position, and the letters are written directly when the search means detects that the two keys have been pressed simultaneously. Therefore, the invention is restricted only by the content of the following claims.

Claims (5)

1. An alphanumeric keyboard (1) that includes a plurality of numeric keys and function keys that are characterized in that the keyboard (1) is programmed so that the simultaneous oppression of two mutually adjacent (t) keys will always generate an alpha-letter and this way the oppression of only one numeric key will always generate a number.

2. A keyboard according to Claim 1, characterized in that the alpha and numeric characters are generated as a key (T) or two keys return from a depressed position.

3. A keyboard according to Claim 1, characterized in that the numbers are generated with the return of a key (T) from a depressed position, and that alpha letters are generated when two keys (T) are pressed simultaneously.

4. A keyboard according to Claim 3 or Claim 3, characterized by a search means that is initiated by pressing a key (TI) to investigate for a predetermined period of time if an adjacent key is depressed.

5. A keyboard according to any of Claims 1-4, characterized in that the alpha letter that is generated when two adjacent keys (T) are pressed simultaneously is marked on the keyboard case (2) between a relevant pair of keys ( T).