A page-turning device comprises a bi-directional drive and a page-turning unit including an arm of crescent shape having an outer convex surface engageable with the underface of the uppermost page on one side of the book center-line for turning same when the unit is driven in one direction, and an inner concave surface engageable with the uppermost page on the other side of the book center-line for turning the page when the unit is driven in the opposite direction. The unit preferably has two (or more) such arms equally spaced about the circumference of the unit. The illustrated device includes two of such page-turning units, one serving to turn the pages and the other serving to pick them up according to the drive direction. Each unit may include a helical recess for pre-loading the pages, or an arcing finger for arcing each page before being engaged by the respective arm.

BACKGROUND OF THE INVENTION 
The present invention relates to page-turning devices, such as are used for 
turning the pages of bound music pads or other bound books. 
A number of page-turning devices have been proposed, but insofar as I am 
aware, none have gained any significant widespread use. An object of the 
present invention is to provide a new page-turning device having a number 
of improvements, as will be described more particularly below. 
SUMMARY OF THE INVENTION 
According to a broad aspect of the present invention, there is provided a 
page-turning device for turning the pages of a book bound along its 
center-line, comprising: a holder for the book; a rotatable page-turning 
unit supported on the holder along one horizontal edge at one side of the 
book center-line for individually turning the pages; and a drive for 
rotating the page-turning unit; characterized in that the drive is 
bi-directional for selectively driving the page-turning unit in either the 
forward direction or the reverse direction; and in that the page-turning 
unit includes an arm of crescent shape having an outer convex surface 
engageable with the underface of the uppermost page on one side of the 
book center-line for turning same when the page-turning unit is driven by 
the drive in the forward direction, the crescent-shape arm having an inner 
concave surface engageable with the underface of the uppermost page on the 
other side of the book center-line for turning same when the page-turning 
unit is driven by the drive in the reverse direction. 
According to another feature of the present invention, the page-turning 
unit may include a helical recess terminating at one end in the arm, and 
at the opposite end in an annular recess such that a number of pages of 
the book may be pre-loaded in the helical recess and the remaining pages 
of the book may be retained in the annular recess. 
According to another feature, the device may include means for arcing the 
page to be turned during a page-turning operation, comprising a finger 
engageable with the outer end of the page to be turned, and means coupling 
the finger to the drive such that at the beginning of the page-turning 
operation the finger moves the outer edge of the page inwardly toward the 
book center-line to cause the page to be arced for receiving thereunder 
the page-turning arm. 
According to a still further feature, the device may include a second 
rotatable page-turning unit supported on the holder on the opposite side 
of the book center-line and coupled to the drive, the second page-turning 
unit being of like construction as the first-mentioned one and oriented 
such that rotating both units in one direction of the drive causes the 
first-mentioned unit to turn the pages from one side of the book 
center-line to the other, while the second unit picks up the pages so 
turned; and rotating both units in the opposite direction causes the 
second unit to turn the pages from the opposite side of the book 
center-line while the first-mentioned unit picks up the pages so turned. 
Further features and advantages of the invention will be apparent from the 
description below.

DESCRIPTION OF PREFERRED EMBODIMENTS 
The device illustrated in FIG. 1 comprises a holder, generally designated 
2, for holding the book 4 whose pages are to be turned. The device 
illustrated in FIG. 1 is particularly useful for turning the pages of a 
music pad, but may be used with respect to other books bound along the 
book center-line 5, as illustrated. In the example shown in FIG. 1, the 
page-turning device is supported on a stand 6 and is foot-operated by a 
foot pedal drive 8; alternatively, it could be operated by an electric 
motor drive actuated by a foot switch 9. 
The illustrated device includes two page-turning units, designated 10a and 
10b, respectively, in FIGS. 1 and 3, supported on the book holder 2 on 
opposite sides of the book center-line 5. The construction of each of the 
page-turning units is more particularly illustrated in FIG. 2, and is 
therein designated 10. It includes a page-loading section 11 formed with 
two parallel, helical recesses or grooves 12, 12', each terminating in an 
arm 13, 13' of substantially crescent shape. Each unit 10 further includes 
a sprocket wheel 14 at its opposite end for rotating the unit about an 
axis 15. It will be seen that each of the page-turning arms extends in the 
radial direction from the axis of rotation 15 with its crescent shape 
providing an outer surface of convex configuration, and an inner surface 
of concave configuration. As will be explained more particularly below, 
the convex outer face of each arm engages the pages on one side of the 
book center-line for turning the pages in one direction, and the concave 
inner face of each arm engages the pages on the other side of the book 
center-line for turning the pages in the opposite direction. 
At the inner end of the two helical recesses 12, 12' the unit is formed 
with an annular recess 16 of substantially greater width than the pitch of 
the helical recesses, for receiving the remaining pages of the book 4 
which are not pre-loaded into the helical recesses 12, 12'. Annular recess 
16 is of adjustable width, enabling it to be prefixed according to the 
thickness of the book 4, and particularly according to the number of pages 
of the book which are not pre-loaded in the helical recesses 12, 12'. For 
this purpose, each unit 10 is made of two parts, namely: one part 
including the helical recesses 12, 12' and radial arms 13, 13'; and a 
separable part including the sprocket 14. The first part terminates in a 
cylindrical pin 20 formed with an axial bore 22, and is telescopically 
received within the second part in the form of an annular sleeve 24 fixed 
to the sprocket wheel 14. Sleeve 24 is formed with an axially-extending 
pin 26 received within bore 22 of pin 20. The two parts are fixed in the 
desired position by a threaded fastener 28, and are keyed to each other 
against rotation, e.g. by bore 22 and pin 26 both being of square 
cross-section. 
The holder 2 of the illustrated page-turning device includes a bottom 
horizontal leg 30 for supporting the book 4, and a backing member 32 (FIG. 
3) forming a backing wall for supporting the back of the book. In 
addition, the holder includes an arm 34 pivotably mounted on the 
horizontal leg 30 in front of the center of the backing member 32 and 
engageable with the book 4 along its center-line 5 for clamping the book 
between it and the backing member. Arm 34 is illustrated in FIG. 3 as 
being in its closed, vertical position to engage the book along its 
center-line 5, and thereby to firmly clamp the book between it and backing 
member 32 of the holder. 
FIG. 3a illustrates a preferred modification in the construction of the 
page-turning units, therein designated 10ma, 10mb. In this modification, 
the two helical recesses 12m, 12m' connecting the page-turning arms 13m, 
13m' of each unit to its annular recess (corresponding to 15 in FIGS. 2 
and 3) for receiving the non-pre-loaded pages of the book, are open and 
have a pitch larger than the remainder of the helical recesses. Such an 
arrangement permits the helical recesses to self-load with one of the 
non-pre-loaded pages, during each page-turning operation, so that the 
device can continue to operate even when all the pre-loaded pages have 
been turned. 
The illustrated page-turning device further includes a pair of retainer 
arms, 36a, 36b, at the outer ends of the pages on opposite sides of the 
book center-line. These retainer arms are operated by the drive to retain 
the book in its open condition. 
As indicated earlier, the helical recesses 12, 12' on each of the 
page-turning units 10 are provided for pre-loading the book pages to be 
turned. When these helical recesses are omitted, it is desirable to 
include page-arcing means cooperable with the arms of the page-turning 
device to arc the pages and thereby to assure that the arms of these units 
will engage the under face of each page to be turned. The latter 
page-arcing means comprise a pair of fingers 38a, 38b engageable with the 
outer end of each of the two opened pages at a point adjacent to its lower 
horizontal edge supported on ledge 30, which fingers are movable towards 
the book center-line, for arcing the respective page; and a further pair 
of fingers 40a, 40b each engageable with the opened page at a point 
thereof between the point of engagement of fingers 38a, 38b and the book 
center-line 5, for retaining the page in place during the above-described 
inner movement of the fingers 38a, 38b in order to produce an arcing of 
the page. Fingers 40a, 40b can be omitted in many cases, as will be 
described below. 
The drive for moving all the foregoing elements is schematically 
illustrated in FIG. 4, wherein it will be seen that the foot pedal 8 is 
coupled, by a link 50 extending through the stand 6, to mechanism disposed 
within a housing 52 at the upper end of the stand 6. The latter mechanism 
includes a selector knob 54 which may be manually moved to one of two 
positions in order to preselect the direction of page-turning. Thus, 
moving knob 54 to the "LR" position illustrated in FIG. 1 effects a 
turning of the pages in the left-to-right direction, and moving knob 54 to 
the "RL" position effects a turning of the pages in the right-to-left 
direction. 
As shown particularly in FIG. 4, selector knob 54 includes a coupling 
element 54' positionable, according to the position of the knob, to couple 
either a first stem 56a, or a second stem 56b, to link 50 of the foot 
pedal drive 8, so that the selected stem is depressed, against the action 
of its spring 58a, 58b, by the depression of the foot pedal 8. 
Link 50 is also coupled to the two retainer arms 36a, 36b, so as to open 
both retainer arms when the foot pedal 8 is depressed at the beginning of 
a page-turning operation, and to reclose the arms when the pedal is 
released at the end of a page-turning operation. The coupling between link 
50 and the retainer arms 36a, 36b is schematically shown in FIG. 4 as 
including a first belt 60 fixed at one end to the upper end of stem 50, 
and at the opposite end to a drum 62 on which it is windable, and two 
further belts 64 each fixed at one end to drum 62 and at the opposite end 
to two pulleys 66 coupled to the two above-mentioned retainer arms 36a, 
36b, the latter being spring-urged to arm-closed positions illustrated in 
FIG. 4. 
The two depressable stems 56a, 56b are each coupled to the sprocket 14a, 
14b of its respective page-turning unit 10a, 10b, via a mechanism, 
schematically illustrated in FIG. 4, as including a pulley belt 70a, 70b, 
fixed at one end to the respective stem 56a, 56b; a rack 72a, 72b fixed to 
the opposite end of the pulley; and an intermediate gear 74a, 74b 
interposed between each rack 72a, 72b and its sprocket wheel 14a, 14b. The 
two racks 72a, 72b are normally retained in their illustrated outermost 
positions by springs 76a, 76b; but each rack, as selected by selector 
knob 54, is movable inwardly towards the book center-line 5 upon 
depression of the foot pedal 8 to rotate its respective sprocket wheel 
14a, 14b. Both sprocket wheels are coupled together by a belt 78 so that 
the rotation of one will also effect the rotation of the other in the same 
direction; but the direction in which both are rotated by the depression 
of the foot pedal 8 depends on the position of the direction selector knob 
54. 
The intermediate gears 74a, 74b coupling the racks 72a, 72b to their 
respective page-turning units 10a, 10b are each rotatably mounted within 
an elongated slot 80a, 80b, and are each normally urged, by a spring 82a, 
82b, out of engagement with their respective sprocket wheels. However, 
when one of the racks (e.g., 72a) is moved inwardly by the depression of 
foot pedal 8, the rack also moves its gear (e.g., 74a) towards its 
respective sprocket wheel (e.g., 14a), whereby the gear becomes effective 
to couple the moved rack to the sprocket wheel; but as soon as the rack 
has completed its inward (driving) stroke and starts to return (outwardly) 
to its normal position, its gear moves away from the sprocket wheel, 
thereby decoupling the latter from the rack during this return stroke. 
Accordingly, during each operation of the device, only one rack (72a or 
72b) will be positively driven by the foot pedal drive 8, but both of the 
sprockets 14a, 14b will be driven so that the arms of the two units driven 
by the sprocket wheels 14a, 14b will also be driven, the direction 
depending upon the selector knob 54. 
The two fingers 38a, 40a are coupled to their respective rack 72a such that 
when the rack is actuated, the two fingers are moved in synchronism to 
produce an arc in the page to be turned, in order to facilitate the entry 
of the respective page-turning arm (e.g. 13ma of FIG. 3a) under the page 
to be turned at the beginning of the page-turning operation. Both fingers 
38a and 40a are coupled to their respective rack 72a by a coupling 
schematically indicated at 84a and 86a. 
In order to permit the arc-producing fingers 38a to accommodate different 
sized books, it preferably is mounted on an arm 88a (see FIG. 3) which is 
adjustable by loosening a threaded fastener 90a, to permit it to be preset 
with respect to the book center-line 5 according to the size of the book 
to be clamped to the holder. 
A similar arrangement producing a similar operation is provided with 
respect to fingers 38b and 40b coupled to rack 72b so as to produce an arc 
in the opposite page upon the depression of foot pedal 8 when the 
direction selector 54 is set to effect a right-to-left turning of the 
pages. Preferably, the fingers 38a, 38b, as well as 40a, 40b, are made of 
transparent plastic. 
The operation of the device of FIGS. 1-4 will be understood by reference to 
the diagrams of FIGS. 5a-5c and 6a-6d. FIG. 5b illustrates the operation 
of the page-turning unit 10b to effect a right-to-left turning of the 
pages, and the diagrams of FIGS. 6a-6d illustrate the movement of the 
fingers 38b and 40b during this operation; this operation is produced when 
the direction selector 54 is set to the "RL" (FIG. 1) position and the 
foot pedal 8 is depressed. In the normal condition of the illustrated 
device, the two retainer arms 36a, 36b, and the page-arcing fingers 38a, 
38b and 40a, 40b are all in their closed positions spring-pressed against 
the open pages of the book. 
At the beginning of the depression of the foot pedal with selector 54 in 
the "RL" position, rack 72b (FIG. 4) begins to move inwardly towards its 
sprocket wheel 14b. At the beginning of this movement, its finger 38b 
(FIG. 6a) begins to move inwardly towards the book center-line. This 
causes the page to arc, as shown in FIG. 6b, permitting the page-turning 
arm 13b to enter the space between the upper arced page and the underlying 
page. As soon as the arm has entered this space, both fingers 40b and 38b 
disengage from the page (FIG. 6c), permitting the arm to start to turn the 
page toward the book center-line. At this time, inner finger 40b returns 
to engage the underlying page (FIG. 6d), while arm 13b of unit 10b comes 
into position behind the page being turned and begins to turn the page 
toward the book center-line 5. As the page approaches the center-line, an 
arm 13 of the other unit 10a comes behind the page, picks it up, and 
completes the turning movement. At the end of the page-turning operation, 
the page-arcing fingers 38a, 38b, 40a, 40b return into engagement with the 
open page. 
The retaining arms 36a, 36b move out of engagement with the book pages at 
the beginning of the page-turning operation, and return into engagement 
with them at the end of the page-turning operation. 
It will be appreciated that the convex outer surface of arm 13b of unit 10b 
engages the underface of the page being turned and starts the turning of 
the page, while the concave inner face of arm 13a of unit 10a picks up the 
page as it approaches the book center-line 5 and completes the 
page-turning operation, as shown in FIG. 5b. 
When the direction selector 54 is set to the "LR" (FIG. 1) position, the 
same operation occurs, except that the left unit 10a starts the 
page-turning operation, and the right unit 10b completes it, as 
schematically indicated in FIG. 5c. It will be appreciated that both units 
10a, 10b may therefore be used for turning the pages in either direction, 
the direction being selected by the selector 54. 
However, the bi-directional turning of the pages can also be effected by 
the use of only one unit, 10a or 10b, together with the page-arcing 
fingers 38a or 38b. Thus, if, e.g., only unit 10b is provided, the 
page-arcing finger 38b can be actuated as described above, i.e. 
counter-clockwise, in order to arc each page on that part (right part in 
FIGS. 5a-5c and FIGS. 6a-6d) of the book center-line 5 in order to enable 
the outer convex surface of the respective arm 13b to engage the page and 
to turn it, the arm in this case being extended so as to project 
substantially past the book center-line and thereby to complete the 
page-turning operation itself. On the other hand, if the pages are to be 
turned in the opposite direction, unit 10b would be rotated in the 
opposite direction (i.e., clockwise) and would cooperate with the 
page-arcing finger 38a on the opposite side (left) of the book 
center-line, the latter arcing the page at the beginning of the 
page-turning operation to assure that the concave inner face of the arm 
engages the page to be turned and turns it during the continued rotation 
of the unit 10b. 
It will also be appreciated that in either case, fingers 40a, 40b may be 
omitted, in which case the arcing of the respective page would between the 
respective fingers 38a, 38b and the book center-line 5. 
The device illustrated in FIGS. 1-4 is particularly useful for clamping to 
an existing stand 6, or to another support, this being effected by the use 
of a pair of clamping fasteners 90. The device, however, can be built into 
a stand, this being shown at 2' in FIG. 7. Particularly when built into a 
stand, it may be desirable, as shown, to provide the backing wall in the 
form of an open frame 92, which frame includes a center vertical bar 93 
terminating in a horizontal bar 94, such that the book is firmly held in 
position between a front clamping bar 34' (corresponding to bar 34 in FIG. 
1) and the horizontal back bar 94. The stand 2' illustrated in FIG. 7 is 
of the collapsible type, and is attachable to the vertical standard by a 
clamping bar 95. 
The drawings illustrate each of the two page-turning units as including two 
radial arms of crescent shape located at opposite sides of the units, so 
that each unit need be rotated only one-half revolution to effect a 
complete page-turning operation. However, each unit may include only one 
such page-turning arm, in which case it would require a complete 
360.degree. rotation for a page-turning operation; or it could include a 
larger number of arms to correspondingly decrease the rotation needed in 
order to effect a turning of a page. FIG. 8 illustrates such a unit, 
generally designated 110, as including four such radiating arms 113, 
equally spaced about the circumference of the rotational axis of the unit. 
It will be appreciated that a four-arm unit as illustrated in FIG. 8 will 
require but a one-fourth revolution to turn a page. 
It will also be appreciated that any or all of the page-arcing fingers 38a, 
38b, 40a, 40b may be omitted, or may be provided and selectively decoupled 
by disconnecting them from the drive (e.g., from their racks 72a, 72b), 
according to the particular application of the device. 
Many other variations, modifications and applications of the invention will 
be apparent.