Album with foldable sheets

An automatically foldable and unfoldable album assembly includes a front cover and a rear cover hingedly joined together and a plurality of foldable sheets joined together in strip fashion. Each sheet contains four panels which are joined together along diagonal fold lines. A pair of opposed inner panels are provided with central vertical folds. The outer panels of adjacent sheets are joined together and are joined to the front and rear cover to form a strip. When one sheet is closed, a sheet adjacent thereto will automatically be opened.

BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
This invention relates to an automatically foldable and unfoldable album or 
book assembly and, more particularly, to such an album which includes a 
plurality of foldable sheets joined together in a strip fashion. 
(2) Description of the Prior Art 
Foldable sheets, which may be collapsed or folded together so as to occupy 
a fraction of the space occupied in the unfolded state, are well known in 
the prior art. A variety of foldable sheet configurations have been 
developed and examples of these are shown in U.S. Pat. Nos. 2,525,937; 
3,753,558 and 4,502,711. These sheets are automatically unfolded and 
folded when opened and closed. The use of a strip type of configuration 
for books, greeting cards and the like is also well known in the prior 
art. Examples of these arrangements are shown in U.S. Pat. Nos. 1,531,065; 
2,546,878; 2,615,732; 2,824,394; and 4,289,333. While the maps shown in 
U.S. Pat. Nos. 1,53l,065; 2,615,732 and 4,289,333 are also partially 
folded, these are simple folds and these maps do not automatically unfold 
and fold when opened and closed. 
It is an object of the present invention to provide a book or album which 
has foldable sheets which are automatically unfolded and folded when the 
book is opened and closed, but which also has a plurality of sheets joined 
together in a strip fashion. 
It is another object of the present invention to provide such an album in 
which each foldable sheet is automatically folded and unfolded with a 
single turn. 
It is a further object of the present invention to provide such an album in 
which, with a single turn, a subsequent sheet is unfolded automatically 
while the immediately preceding sheet is being closed. 
It is yet another object of the present invention to provide such an album 
which is easy to use, which is inexpensive and simple to manufacture, and 
which can be provided in a variety of attractive shapes and 
configurations. 
SUMMARY OF THE INVENTION 
Accordingly I have invented an automatically foldable and unfoldable album 
assembly which includes a front cover and rear cover hingedly joined 
together and having a plurality of foldable sheets joined together in a 
strip fashion. Each of the foldable sheets is formed from a first outer 
panel, a second outer panel, a first inner panel and a second panel, with 
the first inner panel disposed between the outer panels and with the 
second inner panel disposed opposite the first inner panel and between the 
outer panels. All of the panels are joined together along diagonal fold 
lines. Each panel is confined within the diagonal quadrants of a square 
and the outer panels have the same configuration. The inner panels each 
have a central vertical fold extending therethrough and the inner panels 
are complementary with the outer panels whereby when the sheet is moved to 
a folded configuration the inner panels fold toward each other and are 
completely enclosed by the outer panels. In order to join the panels 
together in a strip fashion the rear surface of the first outer panel of a 
first of the sheets is joined to the front cover, a rear surface of the 
second outer panel of the last of the foldable sheets is joined to the 
rear cover and a rear surface of the second outer panel of each of the 
remaining sheets except for the last sheet is joined to a rear surface of 
the first outer panel of the sheet immediately adjacent thereto. 
In a preferred embodiment, the outer panels and the inner panels of the 
foldable sheets are each identical in configuration and are symmetrical 
about a center line passing therethrough. The inner panels will be 
symmetrical about the central vertical fold. The sheets, and hence the 
album, can be provided in a variety of shapes or configurations such as a 
heart, cone, circle, football, and shamrock. It is also preferred that the 
album include some means for securing the front and rear covers together 
when the album is in the folded configuration, such as flexible strips 
attached to the covers. It is also preferred that the front and rear 
covers have the same configuration as the outer panels of the foldable 
sheets.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A first embodiment of an album with foldable sheets in accordance with the 
present invention is shown in FIGS. 1-5. The album includes a front cover 
10, a rear cover 12 and a plurality of foldable sheets 14 disposed 
therebetween. In this first embodiment, the album covers 10 and 12 are 
provided in the configuration of a heart, although as discussed below, 
other shapes or configurations are possible. The front cover 10 and rear 
cover 12 are hingedly joined together by a hinge 16 affixed thereto. The 
hinge 16 is located at the pointed or lower end 18 of front cover 10 and 
the pointed or lower end 20 of rear cover 12. The hinge 16 is ideally a 
length of flexible material. The precise length of hinge 16 is determined 
by the thickness of the album which, in turn, is determined by the number 
of sheets 14 included therein. The front cover 10 and rear cover 12 may 
include tapes or ribbon strips 22 and 24 along an edge opposite pointed 
ends 18 and 20, respectively, so that the covers 10, 12 may be securely 
tied together. 
The album is shown in FIGS. 1 and 2 in the folded or closed position with 
all of the foldable sheets 14 collapsed and located entirely between the 
front cover 10 and the rear cover 12. FIG. 3 shows the album in the 
unfolded or open position and shows one foldable sheet, namely, sheet 26, 
flat and completely unfolded. Sheet 26 is typical of the remaining 
foldable sheets 14 which are not visible in FIG. 3. 
Foldable sheet 26 is formed from four panels, namely, first outer panel 28, 
second outer panel 30, first inner panel 32 and second inner panel 34 all 
joined together along adjacent edges to form a unitary sheet. As shown in 
FIG. 3, the first inner panel 32 is positioned between the first outer 
panel 28 and the second outer panel 30, which are positioned opposite each 
other. The second inner panel 34 is disposed opposite the first inner 
panel 32 and between the first outer panel 28 and the second outer panel 
30. The panels of sheet 26 have V-shaped ends which taper toward the 
center 36 of the sheet 26. The V-shaped ends of each panel abuts and joins 
with adjacent panels along diagonal fold lines which extend outwardly from 
the center 36 of the sheet 26. Panel 28 is joined to panel 32 along 
diagonal fold line 38 and to panel 34 along diagonal fold line 39. 
Likewise, panel 30 is joined to panel 32 along diagonal fold line 40 and 
to panel 34 along diagonal fold line 41. Each diagonal fold line is 
angularly spaced from an immediately adjacent fold line by 90.degree.. 
First inner panel 32 includes central fold line 43 which extend outwardly 
from the center 36 of sheet 26 to the outer edge of sheet 26, bisecting 
the angle between diagonal fold lines 38 and 40 and, thus, bisecting the 
first inner panel 32. Similarly, second inner panel 34 includes central 
fold line 44 extending outwardly from the center 36 of sheet 26 to the 
outer edge of sheet 26, bisecting the angle between diagonal fold lines 39 
and 41 and bisecting the second inner panel 34. 
The diagonal folds 38, 39, 40, and 41 are all directed toward the rear or 
lower surface of sheet 26 as viewed in FIG. 3. The central folds 43 and 44 
are directed toward the front or upper surface of sheet 26. By "directed 
toward", it is meant that the edge or ridge of the fold is on the rear 
surface or on the front surface of the sheet 26, respectively. 
The inner panels 32, 34 are complementary with the outer panels 28, 30 
whereby when the sheet 26 is moved to a folded configuration, the inner 
panels 32, 34 fold inwardly toward each other and are completely enclosed 
or covered by the outer panels 28, 30. This can be explained with 
reference to FIGS. 3 and 4. The foldable sheet 26 has an inherent fold 
memory whereby the sheet 26 automatically folds and unfolds along the 
various fold lines. To close the album shown in FIGS. 1-5, one of the 
outer panels is moved toward the other outer panel. As shown in FIG. 4, 
second outer panel 30 is being moved toward first outer panel 28. As this 
occurs, the first inner panel 32 folds along diagonal fold lines 38 and 40 
and along central fold line 43 and the second inner panel 34 folds along 
diagonal fold lines 39 and 41 and along central fold line 44. Due to the 
arrangement of the fold lines, the inner panels 32, 34 will automatically 
fold inwardly and toward each other, with central fold lines 43 and 44 
approaching and eventually abutting, each other. At the same time, the 
outer panels 28 and 30 approach, and eventually abut, the inner panels 32, 
34. When the album is completely closed, one-half of inner panel 32 abuts 
outer panel 28 and the remaining half abuts outer panel 30. Similarly, 
one-half of inner panel 34 abuts outer panel 28 and the other half abuts 
outer panel 30. Since the inner panels are 32, 34 complementary with, and 
no larger than, the outer panels 28, 30, the inner panels 32, 34 are 
completely surrounded by the outer panels 28, 30 when the album is closed. 
When the album is opened, the above described motion of foldable sheet 26 
is reversed and the sheet 26 is moved to the open configuration shown in 
FIG. 3. 
In a preferred embodiment, the panels of the foldable sheet 26 are 
identical in size and configuration with each other and are each 
symmetrical about a center line therethrough. For example, panel 32 is 
symmetrical about central fold line 43. In addition, the panels preferably 
have the same shape or configuration as the front cover 10 and rear cover 
12. In the embodiment shown in FIGS. 1-5, each panel is heart shaped and 
of the same size and configuration as the other panels. The front and rear 
covers 10, 12 are also heart shaped. The covers 10, 12 are preferably 
slightly larger than the folded sheets 14 so that some measure of edge 
protection for the sheets 14 is afforded. 
The album of the present invention includes a plurality of foldable sheets 
which are joined to the album cover and which are joined to each other in 
a strip fashion. In particular, the rear surface of the first outer panel 
of the first of these foldable sheets is affixed to the front cover of the 
album. The rear surface of the second outer panel of the first foldable 
sheet is affixed to the rear surface of the first outer panel of the next 
adjacent sheet. The remaining foldable sheets are joined together in this 
fashion by connecting the rear surface of the adjacent outer panels 
together. The rear surface of the second outer panel of the last of these 
foldable sheets is then affixed to the rear cover of the album. 
FIG. 5 shows the joining of the foldable sheets together and the operation 
of the album with such foldable sheets. Foldable sheet 26 is shown joined 
to a second foldable sheet 46. Foldable sheet 46 has an identical 
configuration to foldable sheet 26 and includes a first outer panel (not 
visible), a second outer panel 48, a first inner panel 50 and a second 
inner panel 52. Inner panel 50 includes a central fold 54 and inner panel 
52 includes a central fold 56. The panels of sheet 46 are joined together 
along diagonal folds; however, only diagonal fold 58 joining inner panel 
52 to outer panel 48 is visible in FIG. 5. The rear surface of first outer 
panel 28 of sheet 26 is affixed to the inner surface of the front cover 
10. The rear surface of the second outer panel 30 of sheet 26 is affixed 
to the rear surface of the first outer panel of sheet 46. The rear surface 
of the second outer panel 48 of sheet 46 is affixed to the rear surface of 
the first outer panel of the next adjacent foldable sheet. If the album 
included only two foldable sheets, then the rear surface of panel 48 of 
sheet 46 would be affixed directly to the inner surface of the rear cover 
12. 
The operation of the album with a plurality of sheets is similar to that 
described above in connection with FIG. 4. By grasping the second outer 
panel 30 of sheet 26 and the first outer panel of sheet 46, which are 
joined together to form a unitary panel, and moving these panels toward 
panel 28, sheet 26 will begin to close while sheet 46 begins to open. This 
is illustrated in FIG. 5 showing sheets 26 and 46 each in an intermediate, 
partially folded position. By continuing to move panel 30 toward panel 28, 
sheet 26 will eventually close and sheet 46 will eventually open 
completely and resemble the configuration shown in FIG. 3. The remaining 
sheets can be opened in a similar fashion. 
Due to the nature of the folded sheets and their inherent fold memory, the 
sheets will be folded and unfolded automatically with a single turn. Since 
the sheets are joined together in a strip fashion, opening one sheet will 
automatically close another sheet, and vice versa, again with only a 
single turn. 
FIG. 6 is a plan view of foldable sheet 26 with the outline of a square 60, 
divided with diagonal and cross lines, superimposed thereon. Sheet 26 is 
formed to fit completely within the confines of a square 60. Diagonal fold 
lines 38, 39, 40, and 41 follow along diagonal lines 61, 62 extending from 
opposite corners of the square 60. Central fold lines 43 and 44 follow 
along cross line 63 extending between and bisecting opposed sides of the 
square 60. Panel 28 and panel 30 are symmetrical about cross line 64 which 
extends between and bisects the remaining sides of the square 60. It can 
be seen in FIG. 6 that the panels 28, 30, 32, and 34 are each confined 
within a separate diagonal quadrant of the square. 
While the foldable sheet 26 shown in FIGS. 1-6 has four identical panels, 
each of which are symmetrical about their vertical center, this 
arrangement is not absolutely necessary. All that is needed for a foldable 
sheet to function in the present invention is: (a) for the panels to be 
confined within the diagonal quadrants of a square, (b) for the outer 
panels to be identical in configuration, (c) for the panels to be joined 
along diagonal folds, (d) for the inner panels to have a central vertical 
fold, and (e) for the inner panels to be complementary with the outer 
panels. In this manner, the sheets can be joined together in a strip 
fashion and the inner panels will fold inwardly toward each other and be 
completely enclosed by the outer panels when the sheets are closed. 
The configuration of the foldable sheet when closed will be dictated by the 
configuration of the outer panels of the sheet. It is preferable that the 
covers follow the shape of the outer panels of the sheets contained 
therein. The album shown in FIGS. 1-6 has heart shaped panels and the 
shape of the sheets when closed is illustrated by shaded panel 28 in FIG. 
6. Many other shapes for the foldable sheets are possible and several 
examples are shown in FIGS. 7-10. FIG. 7 shows sheet 70 which is comprised 
of cone shaped panels 71, 72, 73, and 74. Sheet 70 has a circular 
configuration when opened or unfolded and a cone shaped configuration, as 
shown in shaded panel 71, when closed. FIG. 8 shows sheet 80 which is 
comprised of circular shaped panels 81, 82, 83 and 84. Sheet 80 also shows 
that the panels need not have V-shaped ends meeting at the center of the 
sheet. The diagonal folds 85-88 of sheet 80 terminate short of the center 
89 thereof. FIG. 9 shows sheet 90 which includes panels 91, 92, 93 and 94 
which have the approximate shape of a football. Sheet 90 has a star shaped 
configuration when opened. FIG. 10 shows sheet 100 which is comprised of 
shamrock shaped panels 101-104. 
Having described hereinabove the preferred embodiments of the present 
invention, it is to be understood that the invention may be otherwise 
embodied within the scope of the appended claims.