US 2782764 A
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Description (OCR text may contain errors)
1957 c. F. LEHMAN, JR 2,732,754
WRITING INSTRUMENT Filed- March 12, 1954 Unitd StatS ,Pa nt .WRITIN G INSTRUMENT Charles F, Lehman, Jr., Fort Worth, Tex., assignor of one-half to'Allen Bronston, Fort Worth, Tex.
Application March IZ, i954, Serial-No. 415,805
1 Claim. (Cl. 120-192) The present invention relates generally as indicated to a writing instrument such as a pencil, pen, and the like.
For the most part, the writing instruments of the character indicated above which are commercially available are of circular cross-section or of hexagonal cross-section and thus do not comfortably fit the normal grip between the tips of the thumb and forefinger and the side of the second finger which, in the normal mode of gripping, define a triangle therebetween. Accordingly, the contact between the fing'ers, as aforesaid, with the circular or hexagonal writing instrument is essentially a line contact except for deformation of the skin and flesh to concave form to conform to the cross-section of the writing instrument. A further objection to the commercially available writing instruments is that the fingers tend to slip therealong unless tightly gripped; and, as a consequence of the tight gripping, there is fatigue, and writers cramp quickly develops.
In view of the foregoing and other objections to commercially available writing instruments, it is one primary object of this invention to provide a writing instrument which has a gripping portion in the general form of a triangular prism to conform to the natural triangle as defined by the bringing together of the thumb, first finger, and second finger to grasp the instrument.
It is another object of this invention to provide a triangular cross-section gripping portion which is depressed with respect to the body of the writing instrument to provide a laterally enlarged base curved to conform to the natural curvature of the adjacent portions of the thumb, first finger, and second finger, said base thus constituting a comfortable stop shoulder to eliminate slipping of the fingers therealong when the writing instrument is in use.
It is another object of this invention to provide a writing instrument of the character indicated in which the triangular cross-section portion gripped between the fingers is offset with respect to the central axis of the holder and writing point of the instrument for achieving a natural, relaxed writing position.
Other objects and advantages of the present invention will become apparent as the following description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claim, the following description and the annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of a few of the various ways in which the principle of the invention may be employed.
In said annexed drawing:
Fig. 1 is a perspective view of a writing instrument embodying the present improvements;
Fig. 2 is an elevation view of the hand showing how the normal gripping of a writing instrument forms a triangle between the thumb, the first finger, and the second finger;
viewedalongthe-lines' 4'4, '5--5,' and 6-6 respectively I ofFig; 3.
'Asi'best shown inFig. l, the writing instrument 1' herein shown for purposes of illustration comprises a pen which includes-an elongatedgcircular cross-section body 10 or holder 2 which terminates in a longitudinally extending whose center'line preferably lies'in adiametral plane through the longitudinal axis-of the body-'2; andin the .case of 'a'pencil or ball-point. pen, for example, the end pen point3 'whose-point-4 is coaxial with body 2 and of the pencil lead or writing ball, as the case may be, will coincide with the center axis of the body 2.
As shown, adjacent the base 5 of the holder, there is provided a depressed gripping portion in the form of a triangular prism to provide three fiat sides 6, 7 and 8 which in cross-section are arranged in approximately isosceles triangular form with slightly rounded corners, said triangle preferably being offset from the center axis of said body 2 and writing point 4 as best shown in Fig. 3. The rear end of said fiat sides 6, 7, and 8 are smoothly curved to meet the remaining portion of said body 2 which is preferably of somewhat larger diameter adjacent the gripping portion and which then tapers gradually to smaller diameter toward the end.
The front ends of said fiat sides 6, 7, and 8 terminate in the laterally enlarged base or shoulder 5, and as best shown in Figs. 4, S, and 6, the side 6 adapted to be contacted by the first finger is rather abruptly curved as at 9 to such base or shoulder 5, the side 8 adapted to be engaged by the side of the second finger is more abruptly curved as at 10 to such base or shoulder 5, and the side 7 adapted to be engaged by the thumb is less abruptly curved as at 11 than either of the front end portions of the other two sides.
It has been found from hundreds of tests of different persons that the normal gripping of a writing instrument defines a triangle 12 (see Fig. 2) including substantially fiat sides as defined by the thumb, the first finger, and the second finger. From such tests, it has been discovered that the triangle is approximately an isosceles triangle, the approximately equal sides 7 and 8 of which are no wider than about .4, and the angle between said sides 7 and 8 is about 45. The only essential variation from such triangle 12 is that, in some relatively few instances, the two approximately equal sides 7 and 8 are defined between the thumb and first finger or between the first finger and second finger; but, in any event, every person can find the best and most comfortable grip, and for this purpose the sides 6, 7, and 8 may be suitably identified as by means of dots or numbers, and the person using the instrument soon will learn on which one of the three sides 6, 7, or 8 the thumb should be placed (or one of the other fingers).
In the majority of instances, the side 6 will be engaged by the first finger, the side 7 will be engaged by the thumb, and the remaining side 8 will be engaged by the side of the second finger, and in such case a diametral plane bisecting the pen point 3 will be offset with respect to the triangular section. In other words, assuming that such diametral bisecting plane is vertical in Fig. 3, the triangle or prism section will be shifted toward the left with respect to the axis of the body and the first finger fiat face 6 of the prism will be sloped slightly downward toward the left, whereas the other two fiat sides 7 and 8 will be sloped upward and outward with respect to the bottom vertex. The length of the triangular prism section wili preferably be about 1.5" before blending in with the adjacent base portion 5 and stem portion of said body 2.
Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in the following claim, or the equivalent of such, be employed.
I therefore particularly point out and distinctly claim as my invention: I
A writing instrument comprising an elongated body terminating in a writing point lying on the longitudinal axis of said body and formed with a generally triangular prism portion having its axis parallel to and offset from the longitudinal axis of said body to provide three generally flat faces for engagement by the thumb, first finger, and second finger when said instrument is held in normal writing position, said prism portion being of cross-section conforming in size and shape to the natural triangle defined by the thumb, first finger and second finger when in writing instrument gripping position, said body having References Cited in the file of this patent UNITED STATES PATENTS 564,178 Ahrens July 21, 1896 843,767 Plach Feb. 12, 1907 FOREIGN PATENTS 337,680 France Feb. 27, 1904