United States Patent [1 1 Friedman Dec. 31, 1974 BOOK INDEXING MEANS [76] Inventor: Arthur S. Friedman, 509 Madison Ave., Room 914, New York, NY. 10022 [22] Filed: July 19, 1973 [21] Appl. No.: 380,599
[52] US. Cl. 283/42 [51] Int. Cl B42f 21/00 [58] Field of Search 253/36-43, 253/35 [56] References Cited UNITED STATES PATENTS 2,398,294 4/1946 Embertson 283/42 3,700,264 10/1972 Friedman 283/38 3,756,627 9/1973 Reist 283/42 Primary ExaminerLawrence Charles Attorney, Agent, or FirmDennison, Dennison,
I Townshend & Meserole [5 7 ABSTRACT The leaves of a book constructed and arranged for flexing during the act of thumbing are arranged as a sequential series of sections, each constituted of a group of leaves wherein the first page face carries indicia identifying that particular group. Each leaf immediately preceding the first leaf of the next following group is an indexing leaf having at its index side edge a marginal zone more flexible than the marginal zones at the index side edges of the immediately preceding and the next following group leaf. The index edges of all leaves have a thumb pressure point that lies in a plane common to all the pointsand normal to the turning axis of the leaves. The pressure points of the indexing leaves are constructed and arranged so that they are less influenced by thumlb pressure than are the pressure points of the group leaf immediately preceding and the group leaf next following each indexing leaf.
2 Claims, .4 Drawing Figures 1 BOOK INDEXING MEANS BACKGROUND The field of this invention is the art of book leaf indexing. As used hereinafter, the term book means any assembly of consecutive leaves bound or otherwise fastened together. along one side edge marginal zone.
The prior art concerned with the indexing of book leaves is replete with various expedients for indexing the leaves to facilitate access to any desired portion of a book. The vast majority of these makes use of visual indicators such as laterally projecting tabs, finger accommodating side edge grooves, etc., all of which depend upon visual identification of a selected portion of a book from its exterior, before it is opened. Upon opening, all leaves preceding the first leaf of a selected portion must be hand lifted and moved as a group to a position in which they do not obstruct view of that leaf, or be allowed to fall by gravity to such position; they do not automatically remove themselves from the desired line of vision when the book is opened.
SUMMARY OF THE INVENTION The invention intrinsic in the embodiment herein disclosed is a means for indexing the leaves of a book in such manner that access may quickly be had to any desired portion thereof, simply by thumbing the leaves so that their free side edges slide beneath the thumb of a person holding a group of consecutive leaves between the thumb and forefinger, as when riffling a deck of playing cards in the act of shuffling. In the present invention, the rate of progression of the leaf edges past the pressure point of the thumb is automatically re tarded at predetermined intervals which individually denote both the ending of a specific group of leaves and the beginning of the next following group. The period of retardation, although miniscule, is nevertheless sufficient to enable optical recognition of identifying indicia on the leading page face of the next following group of leaves. Such indicia characterizes the content or subject matter of the group it identifies.
In the book of this invention, all the leaves are identical in size and configuration, each having a thumb pressure point at its indexing side edge. All the pressure points are disposed at the same location on each leaf and thus are in registry from front to back of the book. The leaf immediately preceding the first page face of the leading leaf in each group is an indexing leaf that functions to accomplish the retardation described in the preceding paragraph.
DESCRIPTION OF DRAWINGS DESCRIPTION OF THE PREFERRE EMBODIMENT As herein disclosed, the book of this invention, B, is a pocket size journal or memorandum book comprising a sequential series of sections each constituted by a group of consecutive leaves indexed to signify the calendar months. It has afront cover 10, a back cover 11, and an assembly ofleaves 12 between them. The book is constructed and arranged for flexing in the act of thumbing; its covers are made of light, flexible cardboard or the like. All the leaves, and preferably also the covers, are identical in size and configuration. The entire assembly of leaves and covers is bound or otherwise fastened together by any suitable means, here shown as aspiral ring binder 20. The side edge of the bookopposite the binder is hereinafter termed its index side edge. All the leaves are equally flexible and may be resilient.
Each group section of the leaves is separated from its next following group by means of an indexing leaf l3 which immediately precedes the first page face of the next following group.
The thumb pressure point at the index side edge of each indexing leaf is anarea 14 constructed and arranged so that -it is less influenced by thumb pressure than the pressure points of the immediately preceding and immediately following leaves, so that it passes beneath the thumb of a person thumbing the book at a faster rate of progression than the pressure points of the section group leaves'which immediately precede and immediately follow it. In the specific embodiment of the invention herein disclosed, thepressure point area 14 is shown as a keyhole slot- 15 opening to the edge of its leaf, but it could equally well be an arcuate cutout or anything which weakens the body of the leaf in the marginal zone in which the-pressure point is located. The pressure points of the section group leaves are not distinctive;'each is simply that point along the index edge of its leaf at which the edge is in frictional engagement with the thumb of a person thumbing the book. In any event, whatever their natures be, all the thumb pressure points of both the indexing leaves and the section group leaves are in alignment in a plane passing through the book normal to the turning axis of its leaves. It is preferred that the pressure points be lo cated substantially midway between the top and bottom edges of the book, but such disposition is not essential. Experiment has proved that the indexing leaves serve their function when thumb pressure is applied anywhere along the entire length of the books indexing side edge, but best operation is achieved when the thumb pressure is applied adjacent the pressure points.
It will be understood that the aperture portion ofkeyhole 15 serves as to prevent further inward tearing or enlargement of the slit part of the keyhole which may otherwise occur during continuous use.
Identification indicia l6 distinctive for each section group of leaves is carried on the first' page face of the leading leaf of its group adjacent its indexing side edge. It may be located at any place in the marginal zone of the first page face in which it is clearly visible when the immediately preceding indexingleaf 13 moves away from the thumb of a person holding the book in the act of thumbing its leaves. Preferably, as best shown in FIG. 4, it occupies a position closely adjacent that portion of the marginal zone which is in registry with thepressure point area 14 of the preceding indexing leaf when the book is closed.
As a matter of illustration but not limitation, thefront cover 10 is formed with athumb guide cutout 17 that is in registry with thepressure point areas 14 of the in MODE OF OPERATION When the book is held as shown in FIG. 3, its leaves naturally assume a convex curvature which places them under tension that spring biases those at the right of the binder to slide from beneath the right hand thumb of a person holding the book and flip over to the left of the binder in the conventional manner of turning the pages of a book by thumbing its leaves. During such operation, the index side edges of the leaves pass in progression beneath the thumb at a fairly uniform rate dependent upon the degree of thumb pressure applied to the pressure points of the leaves. The rate of progression is influenced by the degree of pressure applied. However, whenever thepressure point area 14 of-an indexing leaf passes beneath the thumb, the marginal zone of its leaf is so conditioned that it flexes more readily than the marginal zone of the immediately following section group leaf, so that it passes beneath the thumb at a faster rate than the less flexible marginal zone of the next following section group leaf. The effect of this action is to retard the progression of said next following group leaf just enough to expose its identification indiindicia signals that a desired portion or section of the book has been reached, a slight increase in thumb pressure will stop further progression of the leaves. Actually, during the operation of thumbing, the leaves jump ahead by groups as the various retardation points pass from beneath the thumb.
I claim:
1. In a book having its leaves constructed and arranged for progressive flexing in a thumbing operation and disposed as a sequential series of individual groups of consecutive leaves wherein the groups are separated by an indexing leaf immediately preceding the first leaf of each group and having therein a slit open to its outer side edge, each slit extending inwardly therein and making the area of that leaf adjacent the slit a pressure point more flexible under thumb pressure applied to that point than the remainder of the leaf, and all said indexing leaf slits being in a single plane common thereto and angled relative to the turning axis of the leaves.
2. In the book of claim 1, each indexing leaf slit overlying, when the book is closed, group identification indicia on the first page face of the group leaf which the indexing leaf immediately precedes.