BACKGROUND - FIELD OF INVENTION.

This invention relates to improvements in book marks and other devices distinguished by numerical or symbol differences and, more particularly, to an improved book marking unit for the pages of a book.

BACKGROUND - DESCRIPTION OF PRIOR ART.

Numerous type of bookmarks have been used in the past to indicate the last page of a book which has been read when the reading of the book is to be divided into periods. For the most part, bookmarks are made of a single sheet of cardboard or heavy duty paper for insertion into the book at the location of the last portion to be read. Other technigues for marking a book have been to dog-ear a page by folding it over at the upper corner thereof to indicate the last page of reading by the reader.

While book marks of conventional design are adequate for most purposes, improvements are desirable in this field for one or more reasons. For instance, paper or cardboard bookmarks have a tendency to fall out of the book and the last place where reading stops is lost. Moreover, it is not desired to cause dog-ears to be formed on pages of the book especially if the book is to be saved over a long period of time in a clean condition. Because of these drawbacks, a need exists for improvements in indicating devices which are suitable for use as bookmarks and other such symbol indicating means. The present invention satisfies this need.

SUMMARY OF THE INVENTION.

The present invention provides an improved indicating device which has a number of uses including the use as a book mark. The invention includes a member having the plurality of chambers interconnected by tubes, and the member is closed to the atmosphere and contains a fluid which is oveable from chamber to chamber through the tubes when the and chambers are depressed one by one. For instance, when one of the depressable walls of the chamber is depressed, fluid will flow out of that chamber, through the adjacent tubes and ^" 'into the other chambers. The chambers are all of approximately equal volume and the tubes have volumes which are approximately equal to each other. The volume of the fluid is substantially equal to the combined volumes of the tubes and the chambers minus the volume of one of the chambers. Thus, when one of the chambers is forced downwardly and depressed, the fluid flows out of that chamber

and into the adjacent chamber or chambers, substantially filling the adjacent chamber and also filling the adjacent tubes so that there is always one chamber which is substantially devoid of fluid. The fluid is chosen to prevent flow of fluid in the member until the wall means of the chamber is depressed. To this end, the tubes themselves can be capillary tubes to limit the flow of fluid in the member until one of the chambers is depressed.

Typically, the device, when used as a book mark, is comprised of three members which are arranged vertically on the back or the front of the book in some suitable fashion. The members will be in a column with one column representing the hundreds pages, the second column representing the tens pages and the third column representing single digit pages. Thus, any one of a total number of 999 pages can be marked with the number device having three columns. For a book having more than a thousand pages, a fourth column will be used to represent the thousands numbers.

The member has means to indicate the absence of fluid in a particular chamber. Such means could be a different color on the bottom or inner surface of the chamber, or it could have a numeral or other symbol on the bottom of the chamber which would be observable when the fluid has been substantially purged from the chamber. At any rate, when three members are side by side or in adjacent columns and if numbers are used, the numbers in each member will be observable and these numbers will represent a particular condition of the book, such as the number of pages that have been read or the page which was last read by

the reader .

The primary object of the present invention is to provide an improved numerical indicator device for utilitarian use where the device includes a member closed to the atmosphere and containing a plurality of chambers for containing a fluid oveable chamber to chamber through connecting tubes, whereby the depressing of one of the chambers causes fluid to flow to the other chambers, leaving the one chamber substantially void of fluid and having an indicating symbol representing a particular condition, such as the number of pages in a book having been read to thereby provide an indicator of the present condition of a situation which can be apparent at a glance.

Another object of the present invention is to provide a bookmarking device which allows the reader of a book to operate the device to indicate the page on which the reader stops reading and is to take up reading at the next sitting to thereby eliminate the need for conventional bookmarking devices and techniques and thereby provide an improved bookmarker which is simple in construction, can be attached directly to a book or loosely held therein.

Other objects of this invention will become apparent as the following specification progresses, reference being had to the accompanying drawings for an illustration of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS.

FIG. 1 is a perspective view of a preferred embodiment of the device of the present invention showing a book on which the device is used;

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FIG. 2A is a perspective view of a portion of the device showing the way in which one element of the device is depressed by a finger to force liquid out of the chamber of the element and into an adjacent chamber of the element;

FIG. 2B is a vertical section through the two-e.lement member of Fig. 2A;

FIG. 3 is a view similar to view 2A but showing a greater number of elements connected together with one of the elements being depressed by the finger to operate the device;

FIG. 4 is a perspective view of the device showing the way in which three columns of elements or members are coupled by a card to a book cover or the like;

FIG. 5 is a view similar to Fig. 2B but showing the way in which fluid is forced out of the chamber of one of the elements into the chambers of adjacent elements;

Fig. 6 is a top plan view of a device of the present invention for selectively indicating one day of the week;

Fig. 7 is a top plan view of a device of the present invention for indicating time of day for use as a reminder for appointments, and taking medication, etc.;

Figs. 8 and 9 are views similar to Figs. 6 and 7 but showing a pair of devices, Fig. 8 showing the device for providing multiple choice questions and Fig. 9 showing the device for providing answers or responses;

Fig. 10 is a side elevational view of another embodiment of the device of the present invention, showing the device mounted on a panel and a clip mounted on a panel for attaching the device to a structure;

Fig. 11 is a plan view of a game showing the device in a corner of the game board for keeping score.

DESCRIPTION OF THE PREFERRED EMBODIMENT.

While the present invention is suitable for a number of different uses for indicating numerals or symbols, it is especially suitable for use as a bookmarker. To this end, the device of the present invention is broadly denoted by the numeral 10 and includes a plurality of members 12, 14 and 16 arranged in columns as shown in Fig. 1 on the front cover 18 of a book 20 having a plurality of pages 42 and a rear cover 44. Members 12, 14 and 16 have observable indicia, symbols or numbers which represent the particular numbers of pages of a book which have been read or indicate the last page of a book which has been read at a particular sitting. When the book is next taken up for reading, the person merely glances at the number exposed by members 12, 14 and 16 and knows exactly where to turn to in the book to take up reading once again.

For instance, if the numbers 2, 4, and 8 were to be observable by looking at device 10, the reader will know that he is to start reading again at page 248 because that is the page where he last left off reading. At any one time, only a single number will be visible for each member 12, 14 and 16.

Figs. 2A and 2B indicate the basic operating principle of the present invention. To this end, member 12 will be considered in Figs. 2A and 2B which show only two elements of member 12 since only two are necessary to illustrate the basic concept of the present invention.

Member 12 is comprised of at least two elements 22 and 24 which are formed from a suitable yieldable material, such as a plastic or the like. Elements 22 are hollow as shown in Fig. 2B and element 24 has its upper yieldable, dome-shaped top wall 26 depressed by a finger 28 so that approximately all of the liquid or fluid in chamber 30 of element 24 will be forced through a small tube 32 into chamber 34 of element 22 which also has a dome-shaped top wall 36. The fluid can be a flowable material which is solid or liquid. Typically it is liquid, but it is contemplated that a crystalline, particulate flowable material could be used for the same purpose. Moreover, the top yieldable walls 26 and 36 of elements 22 and 24 can be transparent or translucent so that the color of the material fluid can be quickly seen and if there is almost no color in chamber 30, this means that there is approximately no fluid in the chamber then it is the chamber which is to be indicated. Furthermore, the base walls 38 and 40 of elements 22 and 24 can have numbers on the upper surfaces thereof and these numbers will be viewable to the observer when almost no fluid is in a particular chamber. The numbers could also be exterior to the elements, such as on a card or surface adjacent to the device.

The fluid in the chambers can have a surface tension which is sufficient to prevent flow of the fluid out of element 22 back into element 24 through tube 32 until the wall means 36 of element 22 is depressed. Tube 32 could be a capillary tube which would prevent normal flow of fluid back into chamber 30 of element 24 until pressure is applied to the yieldable top wall 36 of element 22.

Fig. 3 shows a series of five elements having internal chambers connected together by tubes 32. The top wall of the middle chamber is being depressed by the finger so that fluid can flow in opposed directions through the two tubes 32 connected to the middle chamber and into the chambers on opposite sides of the middle chamber. Once the chamber is depressed, it will remain depressed as shown in Fig. 2B until the next depression of a chamber yieldable wall, such as wall 26 of element 24 (Fig. 2B) .

The chambers of the device are all of approximately equal volume, and the tubes 32 have volumes which are approximately equal to each other. The volume of the fluid in the chambers is substantially equal to the combined volumes of the chambers and tubes minus the volume of one of the chambers. Thus, there is always one chamber devoid of fluid.

In use, members 12, 14 and 16 are carried by a card 50 (Fig. 4) and the members are secured to the surface 52 of a book, such as a back cover or front: cover 18 of the book shown- in Fig. 1. The elements of members 12, 14 and 16 are arranged in columns and the book is considered to have less than 500 pages.

Once upper cover 54 is placed on backing 50 and sealed, such as by glue or the like, the holes 56 in cover 54 will overlie the particular elements, such as indicated by the numeral 58 and these elements will project through holes 56 and be depressable so as to force fluid out of a particular chamber and into the adjacent chambers. Fig. 5 shows how fluid will be forced out of a chamber 58A and into adjacent chambers 58B

through connecting tubes 59. The fluid in chamber 58C and 58B is indicated as being in cross hatched form with the fluid being essentially emptied out of the chamber associated with element 58A and the arrows indicating the direction of the fluid flow out of the chamber 58A into the adjacent chambers. Since the fluid is such that the fluid will not return to element 58A until another element is depressed, element 58A will remain empty and will remain depressed until the next element of the member is depressed.

In view of the foregoing, it is clear that by depressing a yieldable top wall of an element in each of the three columns of Fig. 4, three indicia, symbols or numerals will be observable and these indicia, symbols or numerals will indicate a certain condition, such as the number of pages of a book which have been read. An indicator of some such sort such as a number on the base of an element can be viewed to indicate the substantial absence of fluid in the particular chamber and these observable numbers will be seen through the transparent or translucent top dome-shaped yieldable walls of the elements, such as elements 58A, 58B and 58C.

The shapes of the chambers could be different from each other to provide indicia or symbols which convey information of different types. The chambers could be polygonal as well as dome-shaped as shown.

The device can be used to selectively indicate a day of the week as shown in Fig. 6. Each chamber of a single column of chambers of a member 60 is assigned a particular day of the week and is so marked on a card or base 62 to which member 60 is

secured .

The devices of Figs. 7-11 can be used to show different configurations and applications of the present invention. Fig. 7 shows a device 64 having a first circular member 66 of twelve chambers and a second circular member 68 of four chambers, member 68 being within member 66. A two-chamber member 70 is adjacent to member 66. The chambers of member 66 represent the hours of a half-day, the chambers of member 68 represent the quarter hours, and the chambers of member 76 represent a.m. and p.m. A device of Fig. 7 is suitable for use in timing medication dosage, and the device can be used as a reminder as to when a medicine is to be taken or has been taken previously.

Fig. 8 represents a device 72 which can be used for multiple choice questions. The elements A, B, C and D and the reset elements of a five-chamber member 73 are all arranged on a card 74 so as to be different colors and provide the basis for questions for playing the game.

Fig. 9 shows a device 76 made up of a three-chamber member 75 on a card 77 which provides the means for answering or responding to questions.

Fig. 10 shows a device 78 which includes a member 80 mounted on a panel 82. A clip 84 at one end of panel 82 is for attaching the device 78 to the clothing or to a wall or other structure.

Fig. 11 is a plan view of a game board 86 for playing a child's game showing the device 87 in four corners of the board for keeping score. The device has a member 88 with a number of

chambers .

The device of the present invention could also be made waterproof so as to stick onto boats and other watercraft to assist, for instance, in scheduling and accounting for the presence of rental boats in a rental agency. The waterproofing of the device can also be suitable to make score pads as well. The invention can be a device printed with-12- braille adjacent to the chambers of the device for use by the blind.