GB2122947A - Key-operated machine - Google Patents

Abstract

A keyboard (10) for a key- operated machine comprises keys (20) arranged for operation upon application of an operating pressure by the fingers of the machine operator. The operating pressure of keys (columns 30, 39) that will be depressed by the weaker fingers, for example the little or fourth fingers is less than the operating pressure of the remaining keys. <IMAGE>

Description

SPECIFICATION Key-operated machine This invention relates to key-operated machines, and is particularly concerned with keyoperated stenotyping machines.

A great number of machines are operated by keys, usually representing letters of the alphabet, arranged on a keyboard for depression by the operator's fingers. Upon depression of a key, a switch beneath the key is closed and the machine performs a particular function, for example printing a letter. Such machines include computer input terminals, typewriters and typesetting machines. All the keys are arranged for operation upon application of a particular pressure, usually in the region of 100 g to 200 g. The operating pressure often has to be chosen as a compromise between two conflicting demands:-- for speed the keys must be operated with minimum effort, whereas for accuracy they should be fairly stiff to prevent the machine acting on the depression of keys which receive a glancing blow during depression of an adjacent key.

This problem is particularly severe with keyoperated stenotyping machines, such as the PALANTYPE machine. Such machines are used to produce a phonetic representation of sound.

Words are transcribed syllable by syllable, a combination of keys being used to represent each syllable. The PALANTYPE machine has 29 keys which are arranged in a V-shape with the point of the "V" towards the operator. The keys representing each syllable must be struck simultaneously like a chord on a piano. As some syllables are phonetically rather complex, the operator may sometimes be required to operate more than one key with the same finger, either by pressing adjacent keys in the same row, or by bending the finger under and pressing adjacent keys in the same column. This, together with the somewhat awkward operating position dictated by the V-shaped keyboard, and the speed versus accuracy compromise mentioned above, makes the choice of key operating pressure very difficult.

The present invention provides a keyboard for a key-operated machine which keyboard comprises a plurality of keys arranged for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys.

The invention also extends to a key-operated machine incorporating such a keyboard.

The keyboards of key-operated machines may be notionally divided into regions, the keys in each region being operated by a specific finger of one or other hand. In the simplest case, a key operated machine embodying the invention would have those keys which are to be operated by the little or fourth finger arranged to operate upon application of a smaller pressure than the remaining keys, the travel of the keys remaining the same in all cases.

In a more complex machine embodying the invention, the operating pressure of each key would be chosen with reference to the finger which was to operate it.

This invention is of advantage in the operation of key-operated stenotyping machines, particularly the PALANTYPE machine described above, and the invention will now be discussed in more detail, by way of example, with reference to the accompanying drawing in which the single figure shows a diagrammatic plan view of the keyboard of a PALANTYPE machine. This machine is of the type described in some detail in an article entitled "The development and use of an electric keyboard for television subtitling by Palantype" by W. R.

Hawkins and R. N. Robinson, Int. J. Man-Machine Studies (1979)11,701-710.

As may be seen from the drawing, the keyboard 10 is generally V-shaped and has keys 20 labelled with some of the letters of the alphabet arranged in ten columns 20 to 39 roughly transverse to the arms of the "V". The keys in each column are operated by a given finger as indicated underneath the keyboard. All the keys 20 are commercially available keys with a maximum travel of 4 mm. In this embodiment the keys in the two columns 30 and 29 marked "4", which are operated by the fourth finger of each hand, have an operating pressure of 70 g whilst the remaining keys have an operating pressure of 1 70 g.

As an example, if this keyboard is used to transcribe the single syllable word "friends", the operator's fingers are disposed as follows: left hand, second finger bent under depresses F and R, thumb depresses E; right hand, first finger depresses N, third finger depresses T, fourth finger depresses S.

All these keys must be depressed simultaneously. It will be understood that provision of a lower operating pressure for the key operated by the fourth finger reduces strain on that finger and allows the keys operated by the stronger fingers to support the whole hand without introducing errors.

1. A keyboard for a key-operated machine which keyboard comprises a plurality of keys arranged for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys.

2. A key-operated stenotyping machine having a plurality of keys arranged on a keyboard for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Key-operated machine This invention relates to key-operated machines, and is particularly concerned with keyoperated stenotyping machines. A great number of machines are operated by keys, usually representing letters of the alphabet, arranged on a keyboard for depression by the operator's fingers. Upon depression of a key, a switch beneath the key is closed and the machine performs a particular function, for example printing a letter. Such machines include computer input terminals, typewriters and typesetting machines. All the keys are arranged for operation upon application of a particular pressure, usually in the region of 100 g to 200 g. The operating pressure often has to be chosen as a compromise between two conflicting demands:-- for speed the keys must be operated with minimum effort, whereas for accuracy they should be fairly stiff to prevent the machine acting on the depression of keys which receive a glancing blow during depression of an adjacent key. This problem is particularly severe with keyoperated stenotyping machines, such as the PALANTYPE machine. Such machines are used to produce a phonetic representation of sound. Words are transcribed syllable by syllable, a combination of keys being used to represent each syllable. The PALANTYPE machine has 29 keys which are arranged in a V-shape with the point of the "V" towards the operator. The keys representing each syllable must be struck simultaneously like a chord on a piano. As some syllables are phonetically rather complex, the operator may sometimes be required to operate more than one key with the same finger, either by pressing adjacent keys in the same row, or by bending the finger under and pressing adjacent keys in the same column. This, together with the somewhat awkward operating position dictated by the V-shaped keyboard, and the speed versus accuracy compromise mentioned above, makes the choice of key operating pressure very difficult. The present invention provides a keyboard for a key-operated machine which keyboard comprises a plurality of keys arranged for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys. The invention also extends to a key-operated machine incorporating such a keyboard. The keyboards of key-operated machines may be notionally divided into regions, the keys in each region being operated by a specific finger of one or other hand. In the simplest case, a key operated machine embodying the invention would have those keys which are to be operated by the little or fourth finger arranged to operate upon application of a smaller pressure than the remaining keys, the travel of the keys remaining the same in all cases. In a more complex machine embodying the invention, the operating pressure of each key would be chosen with reference to the finger which was to operate it. This invention is of advantage in the operation of key-operated stenotyping machines, particularly the PALANTYPE machine described above, and the invention will now be discussed in more detail, by way of example, with reference to the accompanying drawing in which the single figure shows a diagrammatic plan view of the keyboard of a PALANTYPE machine. This machine is of the type described in some detail in an article entitled "The development and use of an electric keyboard for television subtitling by Palantype" by W. R. Hawkins and R. N. Robinson, Int. J. Man-Machine Studies (1979)11,701-710. As may be seen from the drawing, the keyboard 10 is generally V-shaped and has keys 20 labelled with some of the letters of the alphabet arranged in ten columns 20 to 39 roughly transverse to the arms of the "V". The keys in each column are operated by a given finger as indicated underneath the keyboard. All the keys 20 are commercially available keys with a maximum travel of 4 mm. In this embodiment the keys in the two columns 30 and 29 marked "4", which are operated by the fourth finger of each hand, have an operating pressure of 70 g whilst the remaining keys have an operating pressure of 1 70 g. As an example, if this keyboard is used to transcribe the single syllable word "friends", the operator's fingers are disposed as follows: left hand, second finger bent under depresses F and R, thumb depresses E; right hand, first finger depresses N, third finger depresses T, fourth finger depresses S. All these keys must be depressed simultaneously. It will be understood that provision of a lower operating pressure for the key operated by the fourth finger reduces strain on that finger and allows the keys operated by the stronger fingers to support the whole hand without introducing errors. CLAIMS

1. A keyboard for a key-operated machine which keyboard comprises a plurality of keys arranged for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys.

2. A key-operated stenotyping machine having a plurality of keys arranged on a keyboard for operation upon application of an operating pressure by the fingers of the machine operator, wherein the operating pressure of keys that will be depressed by the weaker fingers is less than the operating pressure of the remaining keys.