The invention relates to a device for manually inputting information and instructions to an equipment incorporating digital electronic circuits.

BACKGROUND OF THE INVENTION

A common example of such a device is the keyboard having about 100 keys which is used to enter alphabets, numerals, punctuation, symbols, functions, instructions or commands into a computer. Other common examples are keypads having 12 or more keys which are used to enter numerals and tone and redial commands into telephone instruments including mobile phones; keypads with 16 keys or more which are used to enter numerals and functions into a calculator; the handset of a television remote control; keypads with a number of keys which are used to enter information or instructions into numerically controlled machinery and pointing devices such as a mouse or a trackball used for entering information or instructions into a computer.

In the known art, a keyboard or keypad comprises keys which are operated by finger or thumb movement of the operator and a dedicated electronic circuit which identifies which key or keys have been operated and converts this information into coded digital electronic signals, which are transmitted from the keyboard or keypad to the equipment by wired or wireless means.

In the known art, chorded keyboards require few keys, which are to be operated in various combinations simultaneously to obtain the required variety of input signals corresponding to which coded signals are generated. In spite of their advantages, chorded keyboards are not widely used because of difficulties in use.

SUMMARY OF INVENTION

The invention provides a device for manually inputting information and instructions to an equipment incorporating digital electronic circuits, said device comprising at least three pairs of keys with associated switching means, located on the surface of a housing, both keys of each said pair of keys being located in close proximity so that either one key or both keys of said pairs of keys is operable by a single finger of the operator providing up to 63 combinations of operation of said keys using three fingers of one hand, the said switching means being connected to input terminals of a digital signal processing circuit having signal producing means to provide digital signals to the said equipment corresponding to each said combination. It is also possible to provide each pair of keys combined into a single member with a pair of switching means operable independently or together by applying a finger to the key at a different position or in a different direction.

By providing an additional key with associated switching means to the said three pairs of keys for operating with any of the two remaining fingers of the said hand, up to 127 combinations can be achieved. For conveniently operating with a single hand of an operator a few additional keys may be provided. The additional keys may be operated using the remaining two fingers of the operator. The additional keys need not be in pairs of close proximity and may be located at convenient positions for individual operation since the available combinations are more than sufficient for inputting information and instructions to an equipment in most cases.

Preferably the keys may be located on a flat or contoured panel suitable for operating with one hand. Alternatively the keys may be located on the sides of a box with flat and/or contoured surfaces suitable for holding in the palm of a hand with at least the three pairs of keys wherein keys in each pair are located in close proximity on one of the sides of the box. This will enable an operator to operate the three pairs of keys with the forefinger, middle finger and the ring finger of one hand. Additional keys may be located on the surface of the box for operating with the little finger or the thumb finger. The associated switching means and the digital signal processing circuit may be housed inside the box.

Accordingly the present invention provides a device for manually inputting information and instructions to an equipment incorporating digital electronic circuits, said device comprising at least three pairs of keys with associated switching means, located on the surface of a housing such that two keys of each said pair of keys are in close proximity to one another for operating either of the two keys independently or both keys together by a single finger of the operator, providing up to 63 combinations of operation of said keys using three fingers of one hand, the said switching means being connected to input terminals of a digital signal processing circuit having signal producing means to provide output digital signals corresponding to each said combination to the said equipment through signal transmission means.

BRIEF DESCRIPTION OF THE DRAWINGS

The device according to the invention is further illustrated with various preferred embodiments in the accompanying drawings :

Figure 1 shows a schematic diagram showing the circuit configuration of the device according to the invention connected to an equipment incorporating digital electronic circuit. Figures 2A to 2E show five preferred embodiments of the device according to the invention with a panel housing.

Figures 3 A to 3 C, show three preferred embodiments of the device according to the invention with housing suitable for holding in the palm of a hand.

DETAIL DESCRIPTION WITH REFERENCE TO THE DRAWINGS

Each embodiment shown in the figures 2A to 2E represent devices with at least three pairs of keys (K1 to K6) in which the keys of each pair (K1, K2; K3, K4; K5, K6) are located in close proximity for easily operating both keys of each pairs individually or together with a single finger.

Figure 3B and 3 C show embodiments in which one or more additional keys (K7j K8 ) are provided on a side different from the side on which the three pairs of keys (K1 10 K6) are located so that these keys ..can be operated by the thumb finger. Key K9 may be located on the same side on which the three pairs of keys (K1 10 K6) are located, making it easy to operate with the little finger of the operator.

The basic requirement in all these embodiments is that the pairs of keys (K1 10 K6) should be conveniently operable by the fingers of one hand and the keys (K1, K2; K3, K4; K5, K6) in each pair should be located in close proximity for operating with a single finger of the operators hand. Thus operator can operate keys from each pair K1 and K2 or K3 and K4 or K5 and K6 individually as well as together with a single finger. Such an arrangement provides 63 combinations of keys that can be operated at a time using three fingers. As an example, Table IA shows how these combinations can be used as inputs to a computer. In this table column 1 represents a reference number for the input combination, column 2 to 7 represent the state of the keys. The operated state of a key is represented by 1 and the un-operated state is represented by 0. Column 8 shows examples of how the input combination may be assigned to a symbol or character or instruction. The corresponding digital electronic signal generated by the digital signal processing circuit would be as required by the said digital electronic circuits of the equipment and is not shown in the Table. It is possible to obtain additional combinations with the same number of 6 keys, as illustrated in Table IB to ID. For example, if the combination 33 of Table IA "shift" is input, the next input combination and only the next will be interpreted in the digital signal processor as corresponding to Table IB, after which succeeding input combinations will be interpreted in the digital signal processor according to Table IA. If the combination 35 of Table IA "caps lock" is input, succeeding input combinations will be interpreted in the digital signal processor as corresponding to Table 1C till the combination 35 "caps unlock" is input, whereafter Table IA will revert. If combination 39 of Table IA or Table 1C is input, the next input combination and only the next input combination will be interpreted by the digital signal processor as corresponding to Table ID. When an additional key (K7) is employed 127 combinations are possible which can be utilized in innumerable ways. When further additional keys (K8, K9, KlO) are employed, many more symbols or instructions may be represented. In a similar manner many other combinations or tables can be realised with the device according to the invention depending upon the requirement. Since in practice, all the keys for a combination may not be operated at the same instant, and the associated switching means may not operate simultaneously, the digital signal processing circuit is arranged or programmed to identify the input combination of keys which have been operated and process it to give the corresponding output at the point of time when any one key is released after a combination of keys has been operated, or alternatively at the point of time when all the keys are released after a combination of keys has been operated, or alternatively at the point of time when one of a set of predetermined keys is operated which set may comprise one or more of the available keys.

The switching means (M1) associated with the keys may employ mechanical make-break electrical contacts or electronic circuits which incorporate inductive, capacitive or optical sensing means. The output digital signals from the signal producing means of the digital signal processing circuit (P) may be transmitted to the digital electronic equipment (E) by signal transmission means (M2) which may be wired or wireless means. The device according to the invention can be made for conveniently operating keys K1 to K6 with three fingers of a hand preferably the forefinger, middle finger and the ring finger. The additional keys K7 to K10 may be located for conveniently operating with the thumb finger and/or the little finger. The shapes and sizes of the keys may be decided by a compromise between the ease of operation and the constraints of the equipment with which it is to be used.

The device according to the invention can be made to suit many equipments such as computers, telephone including mobile telephones, numerically controlled machinery, calculators. Pointing devices such as mouse or track ball may be incorporated in the same housing as that of the device. The device may be built into the equipment.

The device according to the invention is also cost effective and suitable for both portable equipments as well as stationary equipments.