Abstract:
An apparatus for turning bound pages, the apparatus having a support assembly for holding the bound pages; a lifting assembly coupled to the support assembly and capable of lifting at least a portion of a page; a turnstile assembly, the turnstile assembly comprising a plurality of flippers; and a motor assembly secured to the support assembly and coupled to the turnstile assembly; wherein the turnstile assembly has a rest position in which one of the plurality of flippers is positioned across two opposed bound pages to hold the bound pages in an open condition; wherein the turnstile assembly is rotated by the motor assembly causing the lifting assembly to lift one of the pages and one of the plurality of flippers to rotate underneath the lifted page; and wherein the finger underneath the lifted page is rotated to turn the page and to place the turnstile in the rest position.

Description:
BACKGROUND 
   The present invention relates to a system and method for automatically turning the pages of a book, magazine, or any bound printed matter in the forward or reverse directions. 
   Page turning is an important ancillary process of reading. It is a pervasive task that many people take for granted. An automatic page turner can assist people with disabilities and the elderly, who may have limited upper extremity function. A page turner can also furnish hands-free operation to musicians, and provide avid readers with convenient book support and page turning features. 
   While there are many patents on the subject of automatic page turners, virtually none of them have led to successful working products. This is due to the fact that all of the patents lack one or two of the three major functions of a successful page turner: engagement with the page, transport of the page, and restraining the book pages to lie flat. The prior art is replete with designs that are too bulky, noisy, unreliable, or burden the user with the requirement to attach clips or tabs to each page. 
   Some relevant patents in this area include: U.S. Pat. No. 4,040,195 to Claypool et al., U.S. Pat. No. 4,160,334 to Willis, U.S. Pat. No. 4,644,675 to Berger et al., U.S. Pat. No. 4,719,712 to Moreau et al., U.S. Pat. No. 5,203,248 to Carr et al., U.S. Pat. No. 5,233,900 to Fitzgerald, U.S. Pat. No. 5,373,772 to Shemoul, U.S. Pat. No. 5,493,943 to Horikawa, U.S. Pat. No. 5,575,097 to Chou et al., U.S. Pat. No. 5,962,801 to Bowman et al., and U.S. Pat. No. 6,049,033 to Dallas. 
   The present invention seeks to remedy the defects of the prior art. 
   SUMMARY 
   Accordingly, the present invention, is directed to an apparatus for turning bound pages that remedies the defects of the prior art. According to a first embodiment of the present invention, the apparatus has a support assembly for holding the bound pages. A lifting assembly is coupled to the support assembly and is capable of lifting a portion of a page. The apparatus also has a turnstile assembly, the turnstile assembly having multiple flippers. A motor assembly is coupled to the support assembly and coupled to the turnstile assembly. 
   The turnstile assembly has a rest position in which one of the flippers is positioned across two opposed bound pages to hold the bound pages in an open condition. The turnstile assembly is rotated by the motor assembly causing the lifting assembly to lift one of the pages and one of the plurality of flippers to rotate underneath the lifted page. The finger underneath the lifted page is rotated to turn the page and to place the turnstile in the rest position. 
   Optionally, the support assembly has an expandable bracket for supporting a spine of the bound pages. A horizontal crossbar can be mounted on the expandable bracket. A pair of expandable folding arms can be coupled to the horizontal crossbar. 
   The motor assembly can have a reversible electric motor and a gear reducer coupled to the electric motor. An output shaft is coupled to the gear reducer and to the turnstile assembly. Left and right limiting switches are coupled to the electric motor. 
   The turnstile assembly can have a disk coupled to the output shaft of the reducing gear, the disk having a top surface and a side surface. A plurality of pins are coupled to the top surface of the disk and a plurality of limiting pins are coupled to the side surface of the disk. Each of the limiting pins is engageable with the left limiting switch and the right limiting switch. 
   The lifting assembly can include a right lifting assembly and a left lifting assembly. Each lifting assembly can have a base assembly having a track, a board slideably coupled to the track, an L-shaped bracket coupled to the board, and a linkage rotatably coupled to the board. The L-shaped bracket can have a rotatable bias pin, the bias pin being engageable with at least one of the plurality of pins coupled to the top surface of the disk. 
   Each lifting assembly can also have a finger assembly comprising a bar, a yoke rotatably coupled to the board and rotatably coupled to the bar. A cam is coupled to the bar, the cam being engageable with the roller coupled to the support assembly. Upon rotation of the turnstile assembly, at least one of the pins on the disc engages the pin on the L-shaped bracket causing the board to slide along the track and the cam to engage with the roller coupled to the support assembly, thereby causing the bar to rotate relative to the yoke, thereby bringing an end of the bar into contact with a page. Continued rotation of the turnstile assembly causes the linkage to engage another of the plurality of pins on the disc, thereby causing the linkage to rotate the bar and the yoke relative to the board, thereby lifting a page. Optionally, a flexible bellow is attached to the distal end of the bar. 
   According to a second embodiment of the present invention, the apparatus has a rotatable turnstile assembly, the turnstile assembly comprising at least one lifting finger. A transportation assembly is coupled to the turnstile assembly. The transportation assembly has a plurality of finger assemblies. The transportation assembly has a rest position in which the finger assemblies hold the bound pages in an open condition. Rotation of the turnstile assembly moves the transportation assembly in a lateral direction to lift one of the pages and moves the lifting finger underneath the lifted page. The lifting finger underneath the lifted page is then rotated to turn the page. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A better understanding of the present invention will be had with reference to the accompanying drawings in which: 
       FIG. 1  is a front perspective view of a page turner according to a first embodiment of the present invention shown with a casing and a book; 
       FIG. 2  is a front perspective view of the page turner of  FIG. 1  without the casing; 
       FIG. 3  is a rear perspective view of the page turner of  FIG. 1 ; 
       FIG. 4  is a front view of a turnstile assembly of the page turner of  FIG. 1 ; 
       FIG. 5  is a front perspective view of a right side page curling assembly of the page turner of  FIG. 1 ; 
       FIG. 6  is a front perspective view of a finger assembly of the page turner of  FIG. 1 ; 
       FIG. 7  is a front perspective view of a left side page curling assembly of the page turner of  FIG. 1 ; 
       FIG. 8  is a front view of a turnstile assembly showing the orientations of the pins with respect to the left and the right side curling assemblies; 
       FIG. 9  is an illustration of a first portion of the page turning process according to the first embodiment of the present invention; 
       FIG. 10  is a schematic view depicting a second portion of the page turning process according to the first embodiment of the present invention; 
       FIG. 11  is a front perspective view of a page turner according to a second embodiment of the present invention; 
       FIG. 12  is a front elevational view of the page turner of  FIG. 11 ; and 
       FIG. 13  is a side perspective view of the transport assembly of the page turner of  FIG. 11 . 
   

   DETAILED DESCRIPTION 
   Referring to  FIGS. 1 to 3 , an automatic page turner  10  according to a first embodiment of the present invention generally has a book support assembly  12 , a casing  14 , a main frame  16 , a turnstile assembly  18 , a right-side page curling assembly  20 , a left-side page curling assembly  22  and a motor assembly  24 . The main frame  16  has an as L-shaped frame  26  on which the motor assembly  24 , the book support assembly  12 , the turnstile assembly  18  and the page curling assemblies  20 ,  22  are rigidly attached. The casing  14  is rigidly attached to the L-shaped frame  26 , and covers the attachments to the L-shaped frame  26 . 
   Two rollers  27  are located on the sides of the main frame  16 . The rollers  27  are rigidly connected to the main frame  16  through axles  28  and brackets  29 . The rollers  27  can freely rotate on the axles  28 . As explained below, the rollers  27  are utilized by the page curling assemblies  20 ,  22 . 
   Considering the book support assembly in more detail, as shown in  FIGS. 1 and 2 , a support bracket  30  is attached to an upper section of the L-shaped frame  26  to restrain a book  31 . Two extension bars  32  are attached to the L-shaped frame  26 . A bracket  34  is attached to each extension bar  32 . A leaf spring  35  is attached to bracket  34 . The leaf springs  35  support the top 50 to 100 pages  36  of the book  31  that are to be turned. 
   Referring to  FIG. 2 , a T-bracket  42  is moveably connected to the support bracket  30  through a screw  44  and a slot  45 . The height of the T-bracket  42  can be increased or decreased by sliding the T-bracket  42  over the support bracket  30  and then tightening the screw  44 . A horizontal section of the T-bracket  42  has a wide surface where the spine of the book  31  is placed. The wide surface prevents the book  31  from sliding off the T-bracket  42 . 
   To support larger soft cover books, a horizontal extending bar  46  is attached to the T-bracket  42  using a fastener, such as screws or clamps. Folding arms  48  are rotatably attached to the ends of the extending bar  46  by hinges  50 . The folding arms  48  can rotate from 0 to 180 degrees as needed to provide support for large books. 
   Considering the motor assembly  24  in more detail, as shown in  FIG. 3 , the motor assembly  24  is rigidly connected to the frame  26  and comprises a reversible electric motor  52 , a gear reduction box  54  and an output shaft  56 . The electric motor  52  can rotate in the clockwise and counterclockwise directions. The gear box  54  reduces and adjusts the output speed of the motor to a desired speed for turning a book page. The output shaft  56  of the motor  52  transmits the rotation of the motor  52  to the turnstile assembly  18 . 
   Referring to  FIG. 4 , the turnstile assembly  18  comprises a disc  60 . Three page flippers  62 ,  64  and  66  are coupled to the disc  60 . The disc has a center hole  68  surrounded by a sleeve  69 . The output shaft  56  of the motor assembly is inserted into the center hole  68  and is rigidly connected to the disc  60  through a fastener, such as a set screw  70  coupled to the sleeve  69 . 
   Considering the three page flippers  62 ,  64 , and  66  in more detail, both ends of each page flipper have a smooth conical tip  71 . Each page flipper is tangentially and rigidly connected to the side of the disc  60  through two fasteners  72 , such as screws. The orientation of the page flippers  62 ,  64  and  66  is such that the points of contact with the disc  60  are the three vertices of an equilateral triangle. Therefore, the page flippers are 120 degrees apart and are symmetric with respect to the center hole  68 . 
   Three sets of pins, set A  73 , set B  74  and set C  75 , are perpendicularly mounted to a surface of the disc  60 . Each set has three pins, with one of the three pins being associated with each of the page flippers. The pins of a set are oriented with a 120 degree angular distance between them, as shown in  FIG. 4 . 
   The relative orientation of the sets to each other will now be described. One pin of set A  73  is located between one pin of set B  74  and one pin of set C  75 . One pin from each of set A  73 , set B  74 , and set C  75  form a group of pins associated with one of the page flippers  62 ,  64  and  66 . 
   Additionally, three limiting pins  72  are placed at equal intervals on a side of the disc  60 . The limiting pins  72  contact switches coupled to the motor once the disc  60  has rotated sufficiently to turn a page as explained in more detail below. 
   The relative positions of pins within a group will now be described. The radial distance of the pins of set A from the center hole is the largest. The radial distance of the pins of set C from the center hole is the shortest. Within each group, the angular distance AC between the pin of set A  73  and the pin of set C  75  is smaller than the angular distance AB between the pin of set A and the pin of set B. 
   Referring to  FIG. 5 , the right-side page curling assembly  20  comprises a base assembly  82  and a finger assembly  84 . The base assembly  82  comprises a board  86  and an L-shaped bracket  88  connected to the board. A pin assembly  90  is connected to the L-shaped bracket. A pair of parallel tracks  92 , that can be rod shaped, travel through holes in the board  86 . The tracks  92  are attached to an anchor bracket  96 . The anchor bracket  96  is attached to the L-shaped frame  26  using fasteners, such as screws, placed through holes  98  in the anchor bracket. The board  86  slides over the tracks  92  with minimal friction and a spring  100  applies a downward bias force to the board  86  to hold the board at a bottom end of the tracks  92 , away from the book  31 . 
   The pin assembly  90  is connected to the distal end of the L-shaped bracket  88  and comprises an arm  104 , a stopper  106  and a torsional spring  108 . The torsional spring  108  applies a clockwise bias torque to the pin assembly  90  and the stopper  106  prevents the complete rotation of the arm  104 . Thus, the pin assembly  90  rotates about 270 degrees in a counterclockwise direction. The pin assembly  90  engages with the pins of pin set A  73  on the disc  60 . 
   As shown in  FIG. 5 , an L-shaped linkage  109  is rotatably connected to the board  86  through a hinge  110 . The L-shaped linkage  109  has a tip  112  on a first end. The tip  112  engages with the pins of pin set B  74  on the disc  60  as will be described below. A cam  114  is connected to a second end of the L-shaped linkage  109  for contacting and rotating the finger assembly  84 . A spring  116  connects the L-shaped linkage  109  to the board  86  and applies a tensional bias force to the L-shaped linkage  109  causing the L-shaped linkage  109  to rotate clockwise, which keeps the cam  114  in contact with a follower  118  on the finger assembly  84 . 
   Referring to  FIGS. 5 and 6 , the right side finger assembly  84  has an S-shaped bar  120 , a flexible bellow  122  and a yoke  124 . The S-shaped bar  120  is rotatably connected to the yoke  124  through a pin  126  allowing the S-shaped bar  120  to rotate in a vertical plane. A spring  128  connects a distal end of the S-shaped bar  120  to the board  86  and applies a downward bias force to the distal end of the S-shaped bar  120 . The bias force keeps the proximal tip of the S-shaped bar  120  upward and away from the book. A distal end  130  of the bellow  122  is circumferentially corrugated (accordion shaped) to allow a large deflection. A proximal end  132  of the bellow  122  is connected to a proximal end of the bar  120  using a pin. 
   The yoke  124  has a support  134 , which is inserted into a hole in the board  86  allowing the finger assembly  84  to rotate in a horizontal plane in both clockwise and counterclockwise directions. A longitudinal cam  136  is rigidly attached to a side of the S-shaped bar  120 , near the distal end. The longitudinal cam  136  has a smooth curve  138 , as shown in  FIG. 5 . 
   As seen in  FIGS. 2 and 5 , upon forward motion of the finger assembly  84 , the curve  138  moves over the roller  27  causing the S-shaped bar  120  to rotate about the yoke pin  126  toward a book page. Upon rearward motion of the finger assembly  84 , the spring  128  brings the S-shaped bar  120  to an upward rest position. 
   The follower  118  is rigidly attached to the S-shaped bar  120  on a side opposite to the cam  136 . Upon clockwise rotation of the L-shaped linkage  109 , the base assembly cam  114  contacts the follower  118 , causing the finger assembly  84  to rotate about the support  134  in a counterclockwise direction. 
   Referring to  FIG. 7 , the left-side page curling assembly  22  is the mirror image of the right-side page curling assembly  20  with some exceptions. First, the tip end  112  of the L-shaped linkage  109  is slightly longer to engage pin set C  75 . Second, a pin assembly  140  is rigidly attached to a distal end of the L-shaped bracket  88  and comprises an arm  142 , a stopper  144  and a torsional spring  146 . The torsional spring  146  applies a counterclockwise bias torque to the pin assembly  140  and the stopper  144  prevents the complete rotation of the arm  142 . Thus, the pin assembly  140  rotates about 270 degrees in a clockwise direction. The pin assembly  140  is engageable with pin set A  73  on the disc  60 . 
   The left side finger assembly  156  is the same as the right side finger assembly  84  except that the cam  114  is on the left side of the L-shaped linkage  109  and the follower  118  is located on the right side of the bar  120 . 
   Referring again to  FIG. 2 , the right side page curling assembly  20  and the left side page curling assembly  22  are positioned on opposite ends of the device and disposed symmetrically with respect to the center of the disc  60 . The right side page curling assembly  20  turns a page forward, curling the right side page and transporting the page from right to left. The left side page curling assembly  22  turns a page backward, curling the left side page and transporting the page to the right side. 
   As shown in  FIG. 1 , an on/off switch  160  located on the casing  14  energizes the page turner  10  through an electric cord  161  to a conventional electric outlet (not shown). In a portable cordless version of the apparatus, a set of small batteries are used to energize the page turner  10 . Upon manually pressing a forward switch  162 , the motor  52  is energized and the gear reducer  54  rotates the output shaft  56  and the disc  60  in a counterclockwise direction and turns a page from right to left. 
   Similarly, pressing a reverse button  164 , the motor  52  is energized and the gear reducer  54  rotates the output shaft  56  and the disc  60  in a clockwise direction and turns a page from left to right. Other activation means, such as foot pedals, breath-controlled switches, chin switches, or voice activation devices can be used to energize the motor  52  in either forward or reverse directions. 
   Operation of the page turner  10  first involves restraining the book  31  in the book support assembly  12 . The height of the T-bracket  42  may be adjusted by the screw  44 . Depending on the size of the book, a user may open the folding arms  48  and extend the supports for each side of the book as necessary. While resting the spine of the book on the support bracket  30 , a user places a desired number of pages, for example approximately 50 to 100 pages for one hour reading, above the leaf springs  35 , on either side of and under the page flipper  62 , as shown in  FIG. 2 . 
   A rest position of the turnstile assembly  18  is such that the page flipper  62  is parallel to the lower edge of the book and is restraining the bottom of the book. The 50 to 100 pages of reading are restrained between the leaf spring  35  and the page flipper  62 . Additionally, the orientation of pin set A  73  is slightly below the pin assemblies  90  and  140  on the right and the left sides, respectively. 
   Referring to  FIGS. 2 ,  5 ,  8 ,  9  and  10 , an exemplary sequence of operation will now be described. When the forward switch  162  is activated, the motor  52  is energized and the output shaft  56  rotates the disc  60  counterclockwise. As the disc  60  rotates, a pin of pin set A  73  contacts the pin assembly  90  of the right side page curling assembly  20 . Because of the stopper  106 , the pin of pin set A moves the right side base assembly  82  and the right side finger assembly  84  along the tracks  92  and closer to the book. 
   Forward movement of the base assembly  82  brings the finger tip bellow  122  over the lower margin area of the book. At the same time, the cam  136  of the finger assembly  84  goes over the roller  27  which pushes the rear section of the finger assembly  84  upward, bringing the tip  130  of the finger assembly  84  downward. The bellow  122  of the finger assembly  84  is moved over the book and brought downwardly onto a page  36 . The lips of the bellow  122  contact the book page  36  on its lower margin area. 
   As the base assembly is moved forward, the L-shaped linkage  109 , which is coupled to the base assembly, is also moved forward in a linear direction, parallel to the tracks  92 . This linear movement brings the tip  112  of the L-shaped linkage onto the disc  60  and closer to the center hole  68 . Therefore, as the pin of pin set A  73  moves the pin assembly  90  forward, a pin of pin set B  74  contacts the tip  112  of the L-shaped linkage  109 . The pin of pin set B moves the tip  112  forward causing the L-shaped linkage  109  to rotate clockwise about the hinge  110 . Clockwise rotation of the L-shaped linkage brings the cam  114  in contact with the follower  118  causing the finger assembly  127  to rotate counterclockwise around the support  134  of the yoke  124 . 
   Consequently, while the bellow  122  is in contact with the page  36 , the finger assembly  84  is rotated to the left causing the top page of the book to form a curl  166 . At the time the curl  166  is formed, the disc  60  has turned about 60 degrees and the tip  71  of the page flipper  64  is moved under the curled page  166  as shown in  FIG. 9 . Further rotation of the disc  60  moves the page flipper  64  over the lower margin of the book while transporting the page  36  to the other side to complete the cycle. Once the page flipper  64  is in the horizontal position, or the disc has rotated 120 degrees, a limiting switch  166  (shown in  FIG. 2 ) is activated by a limiting pin  72  and the motor  52  is turned off. The page forwarding action can be repeated by pressing the forward switch  162 . 
   No pins of pin set B  74  or pin set C  75  come in contact with the pin assembly  140  of the left side page curling assembly  22 . A pin of pin set A  73  does contact the arm  142  of the left pin assembly  140 . However, the arm  142  rotates on its own axis and does not move the left side page curling assembly  22 . The torsional spring  146  brings back the arm  142  to the stopper  144  position. 
   The pages are turned backward when a reverse button  164  is activated. The motor  52  is then energized and the shaft  56  rotates the disc  60  clockwise. As the disc  60  rotates, a pin of pin set A  73  contacts the pin assembly  140  of the left side page curling assembly  22 . Because of the stopper  144 , the pin of pin set A  73  moves the left side base assembly  82  and the left side finger assembly  156  forward along the tracks  92  toward the book  31 . 
   As with the right side page curling assembly, forward movement of the base assembly  82  and the finger assembly  84  brings the finger tip bellow  122  over the lower margin area of the book and at the same time brings the tip of the bellow  122  downward. Thus, the lips of the bellow  122  come in contact with the book page in the lower margin area, on the left side. At the same time, the base assembly  82  is moved forward along with the L-shaped linkage  109  in a linear direction parallel to the tracks. This linear movement brings the tip  112  of the L-shaped linkage  109  onto the disc  60  region and closer to the center hole  68 . As the pin set A  73  moves the pin forward, a pin of pin set C  75  comes in contact with the tip  112  of the L-shaped linkage  109  and moves the tip forward causing the L-shaped linkage  109  to rotate counterclockwise about the pivot point. 
   Counterclockwise rotation of the L-shaped linkage  109  on the left side, moves the bellow  122  of the finger assembly  84  toward the right side of the book, thereby causing the top page of the book on the left side, to create a curl. At the time the curl is made, the disc  60  has turned about 60 degrees and the tip  71  of the page flipper  66  is moved under the curled page. Further rotation of the disc  60  moves the page flipper  66  over the lower margin of the book while transporting the page to the other side to complete the cycle. 
   Once the page flipper  66  is in the horizontal position, or the disc has rotated 120 degrees, a limiting switch  168  on the right side (shown in  FIG. 2 ) is activated by a limiting pin  72  and the motor  52  is turned off. No pins of the pin set C  75  or the pin set B  74  come in contact with the pin assembly  90  of the right side page curling assembly  20 . A pin of pin set A  73  does contact the arm  104  of the right pin assembly  90 . However, the arm  104  rotates on its own axis and does not move the right side page curling assembly  20 . The torsional spring  108  brings back the arm  104  to the stopper  106  position. The page reversing action may be repeated by pressing the reverse button  164 . 
   It will be understood by those skilled in the art that other means for curling a book page may be employed in place of the bellow  122 . For example, a suction means may be employed to lift a portion of the page to allow a page flipper to get under the lifted portion. 
   A page turner  200  according to a second embodiment of the present invention is shown in  FIGS. 11 to 13 . The page turner  200  has a base  202 , a transport assembly  204 , two rail assemblies  206 , two ramp assemblies  208 , and a turnstile  210 . Each rail assembly  206  has two parallel rods  212  that span the base  202 . The two rods  212  are constrained by two end plates  214  that are connected to the base  202 . 
   Each of the ramp assemblies  208  has an inclined ramp  216  and a top horizontal plate  218 . A bracket  220  is connected to the base  202 . A shaft  222  pivotally connects the ramp assembly  208  to the bracket  220  such that the ramp assembly  208  can rotate about the shaft  222 . A torsion spring  224  on the shaft  222  applies a bias force to the ramp assembly  208 . A stop pin  225  on the ramp assembly  208  contacts a side of the bracket  220  to keep the top plate  218  of the ramp assembly  208  in a horizontal position. 
   As shown in  FIGS. 11 and 13 , the transport assembly  204  has two yoke assemblies  226 , one on each of the left and right sides, and a rack gear  228 . A connecting bar  230  connects the two yoke assemblies  226  and supports the rack gear  228 . The transport assembly  204  is moveable to the left and to the right over the rail assembly  206 . 
   As shown in  FIGS. 11 ,  12  and  13 , each yoke assembly has a base  232 , a yoke  234  coupled to the base  232 , and a finger assembly  236  coupled to the yoke  234 . The base  232  has two parallel cylindrical cavities  238  where the two rods  212  pass through so that the transport assembly  204  can move to the right and to the left. 
   The yoke  234  is pivotally connected to a base bracket  240  by a pin  242  and a torsional spring  244  that is coaxially located on the pin  242 . A vertical pin  246  connects the base bracket  240  to the base  232  and passes through to a lever  248  located below the surface of the base  232 . A limiting lever arm  250  is located near each end of the base  202  on an inferior face of the base  202 , as shown in  FIG. 12 . 
   The base bracket  240  and the yoke  234  are rotatable around the vertical pin  246  when the transport assembly  204  is moved to either side where at such time the lever  248  contacts the lever arm  250 . A torsional spring  252  applies a bias torque to the vertical pin  246  and keeps the lever arm  248  in a neutral position. 
   The base bracket  240  has a roller guide  253  having a slot  254  on its front face. A roller follower  256  is positioned inside of the slot  254  on the front face so as to be vertically moveable. The roller guide  253  also has two slots  258  on its side faces. A pin  260  is positioned in the slots  258  on the side faces so as to be vertically moveable. The pin  260  rests on the roller follower  256 . The distal end of the yoke  234  is slideably coupled to the pin  260 . Therefore, when the roller follower  256  is vertically displaced, so is the pin  260 , the distal end of the yoke  234 , and the associated finger assembly  236  rotates about the pin  242 . 
   A torsional spring  244  applies a bias torque to the yoke  240  and pushes the pin  260 , and the roller follower  256  to an inferior portion of the guide  253 , namely at the heel of the ramp  216 . This bias torque also brings the finger assembly  236  upward and above a book page. The finger assembly  236  has a tip  264  of flat rubber material and a leaf spring arm  266 . 
   The turnstile  210  is coaxially connected to an electric motor  268  and a shaft  270  onto which a pinion gear  272  is mounted. The motor  268  is connected to the base  202 . Teeth  274  on the pinion gear  272  are engaged with teeth  276  on the rack gear  228 . The turnstile  210  is a large disc having two lifting fingers  278 ,  280 . 
   The operation of the second embodiment will now be described where a page is turned from right to left. Once the motor  268  is energized, the pinion gear  272  and the turnstile  210  turn in a counterclockwise direction. The rotation of the pinion gear  272  and the turnstile  210  moves the rack gear  228  and the transport assembly  204  to the left. As the rack gear  228  and the transport assembly  204  move to the left, the roller follower  256  approaches the right ramp  216  and starts to climb up the ramp  216 . The climbing of the roller follower  256  causes the yoke  234  to rotate relative to the base bracket  240  about the pin  242 , thereby swinging the right finger assembly  236  down to the page. Once the roller  256  reaches the top of the ramp  216 , the rubber at the tip  264  of the finger assembly  236  contacts the page and applies a soft pressure on the page while the finger assembly  236  is moving to the left. The pressure is adjustable by selecting different leaf spring arms  266 . 
   As the transport assembly moves further to the left, the roller follower  256  goes over the top horizontal section plate  218  of the ramp assembly  208 , and the finger assembly  236  starts to create a curl on the book page. At this moment, the lifting finger  278  of the rotating turnstile  210  goes under the curled page and transports the page to the other side. Once the roller follower  256  passes an end of the top horizontal plate  218  of the ramp assembly  208 , the roller follower  256  drops down to the base  202  due to the torsional bias spring  244  coupled to the base bracket  240 , which applies a continuous downward (compressive) force to the roller follower  256 . The continuous compressive force from the torsional bias spring  244  also keeps the roller on the surface of the ramp. 
   As the page is being turned, the lever  248  of the left yoke assembly  226  contacts the left limiting arm  250 , which causes the whole left yoke assembly  226  to turn counterclockwise about the vertical pin  246  and move the left finger assembly  236  out of the way, allowing the book page to be turned without any obstruction. As the turnstile  210  continues to turn and move the transport assembly  204  to the left, the base  232  of the left yoke assembly contacts a left limiting switch  282  that is located on the left end plate  214 . The left limiting switch  282  in turn, reverses the polarity of the electric current and thus changes the direction of the motor  268  to the clockwise direction. The changing of the motor direction, causes the transport assembly  204  to be moved to the right and return to the initial rest position. During this movement, the spring  252  on the left yoke assembly turns the left yoke to its original position. While the transport assembly  204  is being returned to its original position, the roller follower  256  of the right yoke moves under the ramp assembly  208 . 
   In a reversible mode of operation, where a page is turned from left to right, the motor  268  is energized to be turned in the clockwise direction and the rack gear  228  is moved to the right. In this mode of operation, the roller follower  256  of the left yoke assembly  226  starts to move up the left ramp  216  and swings the left finger assembly  236  down to the page. The remaining page turning process proceeds as described above. 
   An automatic page turner according to the present invention can handle a wide variety of book sizes, page thicknesses, and books whose pages are not conditioned to readily lay flat when the book is opened. Additionally, all mechanical movement is coupled to a single motor, thereby enabling a low-cost design. 
   Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions described herein. 
   All features disclosed in the specification, including the claims, abstracts and drawings, and all the steps in any method or process disclosed, may be combined in any combination except a combination where at least some of such features and/or steps are mutually exclusive. Each feature disclosed in the specification, including the claims, abstract, and drawings, can be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 
   Any element in a claim that does not explicitly state “means” for performing a specified function or “step” for performing a specified function, should not be interpreted as a “means” or “step” clause as specified in 35 U.S.C. §112.