Keyboard construction

To permit small, closely depressible keys, such as found on telephones and hand-held calculators, to be used by users having long fingernails, the keys are located adjacent a slot in the frame of the apparatus, or adjacent the upper edge of the apparatus. Thus, the pad of the finger contacts the top of the key and the fingernail fits into the slot or fits over the edge of the frame. Hence, the pads of the fingers depress the keys in the same manner when one is wearing long fingernails as used by those having short fingernails.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a new and improved keyboard construction of the 
type where there are a number of closely spaced keys, such as in touchtone 
telephones, hand-held calculators and similar usages. 
2. Description of Related Art 
In some of the modifications of the invention hereinafter set forth, the 
keyboards themselves are substantially conventional in the arrangement of 
the keys in rows and columns. However, the modification of telephone 
instruments, calculators and the like, as hereinafter set forth, has 
never, so far as the inventor is aware, been known. 
SUMMARY OF THE INVENTION 
Users of keyboard equipment who have long fingernails encounter problems in 
using touchtone telephone keys, and other equipment. The pad of the finger 
ordinarily cannot touch the top of the key because the tip of a long 
fingernail touches the frame surrounding the key. Users have attempted 
various relatively unsatisfactory ways of circumventing the problem, such 
as using the tip of the fingernail to depress the key (which may result in 
breaking the fingernail or damaging the fingernail polish), turning the 
finger sideways so that the edge of the finger touches the key (which 
frequently results in a wrong key being punched) or gripping a pencil and 
using the eraser end of the pencil to punch the keys (which requires that 
a pencil be conveniently at hand and also prevents use of a "touch" system 
of depressing keys). In accordance with the present invention, the key is 
so placed relative to a slot or the edge of the frame of the piece of 
equipment that a long fingernail has sufficient clearance so that the pad 
of the finger can depress the key. This is accomplished in several ways, 
such as, by forming a groove in the frame immediately above the key in 
which the fingernail may fit; by forming a slot in the frame which extends 
from the top to bottom and thus provides clearance of the fingernail, or 
by modifying the keyboard so that the keys are adjacent the peripheral 
edge of the instrument. All of these forms of the invention are set forth 
in detail. 
Other objects of the present invention will become apparent upon reading 
the following specification and referring to the accompanying drawings in 
which similar characters of reference represent corresponding parts in 
each of the several views.

Directing attention first to the structure shown in FIGS. 1 and 2, the 
invention is shown incorporated in an otherwise conventional touchtone 
type telephone instrument which has a frame 12 apertured for the 
reciprocation of conventional keys 13 which are arranged in four rows of 
three keys each. The designators on the individual keys are in accordance 
with the arrangement of the standard touchtone telephone keyboard. In 
accordance with the present invention, a slot extends across frame 12 
immediately above each row of keys 13. The slot 14 extends below the top 
surface 15 of frame 12 a sufficient depth to accommodate a long 
fingernail. Thus, as shown in FIG. 2, finger 16 has a pad 17 beyond which 
extends a fingernail 18 the slot 14 is sufficiently deep so that the nail 
18 may extend therein a sufficient depth so that the pad 17 engages the 
top surface of the key 13 and has sufficient additional depth so that the 
pad may depress the key 13. 
Thus, in accordance with FIGS. 1 and 2, the user's fingernails 18 do not 
interfere with the pad 17 of the finger 16 engaging the top surfaces of 
any key 13 and depressing the same in the same fashion as a user with 
short fingernails would normally use the instrument. It will be understood 
that the same principle of a slot 14 across the top of each row of keys 13 
may be used in other instruments, such as calculators, either stationary 
or hand-held, typewriters and the like. Further, the particular 
arrangement of keys shown is that of a standard telephone, the invention 
may be incorporated in other arrangements. 
Directing attention now to FIGS. 3 and 4, a hand-held calculator 21 is 
shown. It will be understood that the arrangement of keys of the 
calculator 21 is subject to wide variation. The calculator 21 has a frame 
22 formed with a top surface 23 through which extend reciprocable keys 24. 
The arrangement and positioning of the keys 24 is subject to wide 
variation. Other features of the particular calculator 21 shown in FIGS. 3 
and 4 include an OFF and ON switch 26, a solar cell 27 and a numeric 
display 28. 
The modification of a standard calculator frame which is illustrated in 
FIGS. 3 and 4 is the provision of throughgoing slots 31, which extend from 
the top surface 23 to the bottom surface opposite the top surface 
immediately above the rows of keys below the top row. As to the top row, 
the keys 24 thereof are located close to the upper edge of frame 22. 
In using the calculator shown in FIGS. 3 and 4, the long fingernails of the 
user extend into the slots 31 or extend out over the top edge of the frame 
22. Thus, the pads of the fingers may engage any of the keys without the 
fingernails interferring. 
FIG. 5 shows a still further modified calculator 21a which has an arcuate 
peripheral edge 36 near which are located keys 24a. In this form of the 
invention, the fingernails of the user extend out beyond the edge 36 so 
that the pads of the fingers may contact any of the keys 24a as desired. 
FIG. 6 shows a modification of the structure of FIG. 5 wherein, instead of 
the edge 36 being arcuate, the frame 22b has an angular periphery 
consisting of a first stretch 38 and a second stretch 39. The stretches 38 
and 39 are shown disposed at a 90.degree. angle. However, it will be 
understood, that the angle may be modified. 
In other respects the calculators 21a, 21b of FIGS. 5 and 6 are similar to 
that shown in FIG. 3 at the same reference numerals followed by the 
subscripts "a" and "b", respectively, are used to designate corresponding 
elements. 
The provision of clearance means for long fingernails shown in the 
accompanying drawings and the foregoing written description may be applied 
to other equipment besides telephones and calculators.