Patent Publication Number: US-10768673-B2

Title: Portable electronic device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional application of and claims the priority benefit of U.S. application Ser. No. 15/491,953, filed on Apr. 19, 2017, now allowed, which claims the priority benefit of U.S. provisional application Ser. No. 62/326,847, filed on Apr. 25, 2016. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a hinge structure and a portable electronic device. More particularly, the invention relates to a hinge structure and a portable electronic device using the hinge structure. 
     DESCRIPTION OF RELATED ART 
     A biaxial pivot structure is adopted most of the time by general notebook computers to connect the hosts and the display screens. The hosts and the display screens may rotate relative to each other through the biaxial pivot structure, such that the hosts and the display screens may be overturned by 360 degrees. Nevertheless, the biaxial pivot structure occupies much space in the notebook computers, and the notebook computers are prevented from bringing thin and lightweight design as a result. On the other hand, in the present market, the lenses of the notebook computers are disposed mostly at the side away from the display screens. 
     SUMMARY OF THE INVENTION 
     The invention provides a hinge structure and a portable electronic device for reducing the size of overall structure to satisfy the requirement for thin and lightweight design of the products as well as enhancing operating convenience for a user. 
     A hinge structure including a first screw rod, a sliding rod, and a second screw rod is provided by the embodiments of the invention. The first screw rod comprises a threaded shaft. The sliding rod is sleeved on the threaded shaft. The second screw rod is sleeved on the sliding rod. The threaded shaft has a first helical slot. The sliding rod has a first guiding portion and a second guiding portion opposite to each other, and the first guiding portion is coupled to the first helical slot. The second screw rod has a second helical slot, and the second guiding portion is coupled to the second helical slot. 
     In an embodiment of the invention, a helical direction of the helical slot and a helical direction of the second helical slot are opposite. 
     In an embodiment of the invention, a helical angle of the first helical slot is greater than a helical angle of the second helical slot. 
     In an embodiment of the invention, a helical length of the first helical slot is greater than a helical length of the second helical slot. 
     In an embodiment of the invention, in the hinge structure, when the first screw rod rotates along a first rotating direction, the first guiding portion is driven by the first helical slot, such that the sliding rod drives the second helical slot through the second guiding portion, and that the second screw rod rotates along a second rotating direction different from the first rotating direction. 
     In an embodiment of the invention, a passive module is further included in the hinge structure and is rotatably connected to the second screw rod, and the passive module has a lens. 
     In an embodiment of the invention, the second screw rod is located between the first screw rod and the passive module. 
     In an embodiment of the invention, the second screw rod is magnetically attracted to the passive module. 
     In an embodiment of the invention, the hinge structure further includes a limiting member, and the limiting member includes a first limiting portion, a second limiting portion, and a third limiting portion. The second limiting portion is located between the first limiting portion and the third limiting portion, and the threaded shaft penetrates through the first limiting portion. The sliding rod may be slidably disposed between the first limiting portion and the third limiting portion and penetrates through the second limiting portion. 
     In an embodiment of the invention, the second screw rod includes a body, and the second helical slot is located on the body. The body may be rotatably disposed between the second limiting portion and the third limiting portion. 
     In an embodiment of the invention, the second screw rod includes a connecting shaft, and the connecting shaft has a first end portion. The first end portion penetrates through the third limiting portion and is secured to the body. 
     In an embodiment of the invention, the hinge structure further includes a passive module. The connecting shaft has a second end portion opposite to the first end portion. The second end portion is inserted in the passive module, and the passive module has a lens. 
     In an embodiment of the invention, the limiting member further includes a securing portion, and the first limiting portion, the second limiting portion, and the third limiting portion are respectively connected to the securing portion. 
     In an embodiment of the invention, the limiting member further includes a third guiding portion, and the third guiding portion is connected to the securing portion and is located between the first limiting portion and the second limiting portion. 
     In an embodiment of the invention, the sliding rod has a sliding slot, and the third guiding portion is coupled to the sliding slot. 
     In an embodiment of the invention, the first helical slot has a first thread and a second thread connected to the first thread. The first thread is away from the second screw rod, and the second thread is close to the second screw rod. 
     In an embodiment of the invention, a helical angle of the first thread is greater than a helical angle of the second thread. 
     In an embodiment of the invention, the helical angle of the first thread is equal to 90 degrees. When the first guiding portion is located in the first thread and the first thread glides relative to the first guiding portion, the sliding rod is at standstill. 
     In an embodiment of the invention, the helical angle of the second thread is less than 90 degrees. When the first guiding portion moves into the second thread from the first thread and the second thread glides relative to the first guiding portion, the first guiding portion is driven by the second thread to enable the sliding rod to slide. 
     A portable electronic device is further provided by the embodiments of the invention, and the portable electronic device includes a first machine body, a second machine body and a hinge structure. The first machine body and the second machine body are pivoted to each other through the hinge structure. The first machine body has a first upper surface and a first lower surface opposite to each other. The second machine body has a second upper surface and a second lower surface opposite to each other. The hinge structure includes a passive module. The passive module has a lens. In a first state, the first upper surface and the second upper surface are opposite to each other. When an angle included between the first upper surface and the second upper surface falls between 90 degrees and 150 degrees, the lens is exposed on the first upper surface and the second upper surface. In a second state, the first lower surface and the second lower surface are opposite to each other. When an angle included between the first lower surface and the second lower surface falls between 50 degrees and 90 degrees, the lens is exposed on the first lower surface and the second lower surface. 
     In an embodiment of the invention, the hinge structure further includes a first screw rod, a sliding rod, and a second screw rod. The first screw rod includes a threaded shaft. The sliding rod is sleeved on the threaded shaft. The second screw rod is sleeved on the sliding rod. The threaded shaft has a first helical slot. The sliding rod has a first guiding portion and a second guiding portion opposite to each other, and the first guiding portion is coupled to the first helical slot. The second screw rod has a second helical slot, and the second guiding portion is coupled to the second helical slot. When the first screw rod rotates along a first rotating direction, the first guiding portion is driven by the first helical slot, such that the sliding rod drives the second helical slot through the second guiding portion, and that the second screw rod rotates along a second rotating direction different from the first rotating direction. 
     In an embodiment of the invention, the hinge structure further includes a sun gear, an annular gear, and a planetary gear. The annular gear surrounds the sun gear, and the passive module is rotatably connected to the annular gear. The planetary gear is coupled to the sun gear and the annular gear. 
     In an embodiment of the invention, the hinge structure further includes a first motion member, an elastic member, and a second motion member. The second motion member is located between the first motion member and the elastic member and is rotatably connected to the passive module. The first motion member has a first sawtooth structure. The second motion member has a second sawtooth structure, and the second sawtooth structure is configured to be matched with the first sawtooth structure. 
     In an embodiment of the invention, the hinge structure further includes a first securing member, a second securing member, and a first connection member. The first securing member is secured to the first machine body, and the second securing member is secured to the second machine body. The first securing member and the second securing member are pivoted to each other. At least one portion of the first securing member is inserted in the first connection member, and at least one portion of the second securing member is inserted in the first connection member. 
     In an embodiment of the invention, in the portable electronic device, when the second machine body rotates relative to the first machine body, the second securing member and the first connection member rotate along with the second machine body. 
     In an embodiment of the invention, the hinge structure further includes a third securing member, a fourth securing member, a second connection member, and a third connection member. The third securing member is secured to the first machine body, and the fourth securing member is secured to the second machine body. The third securing member and the fourth securing member are pivoted to each other. At least one portion of the third securing member is inserted in the second connection member, and at least one portion of the fourth securing member is inserted in the second connection member. The third connection member is secured to the first machine body. The passive module is pivoted to the third connection member, and the third connection member is located between the passive module and the second connection member. 
     In an embodiment of the invention, in the portable electronic device, when the second machine body rotates relative to the first machine body, the fourth securing member and the second connection member rotate along with the second machine body, and the passive module rotates along with the second machine body in a reverse direction. 
     In an embodiment of the invention, the portable electronic device further includes a first magnetic member and a second magnetic member. The first magnetic member is secured onto the passive module. The second magnetic member is secured onto the second screw rod. The second magnetic member and the first magnetic member are aligned with each other and are attracted to each other. 
     In an embodiment of the invention, the portable electronic device further includes a third magnetic member secured to the second machine body. The third magnetic member is disposed at a side of the second machine body close to the hinge structure and is disposed corresponding to the first magnetic member. 
     In an embodiment of the invention, in the portable electronic device, when the passive module rotates relative to the second screw rod such that the first magnetic member moves away from the second magnetic member, the first magnetic member moves close to the third magnetic member, and the third magnetic member and the first magnetic member are repulsive with each other, such that the passive module rotates along a reverse direction. 
     To sum up, in the hinge structure of the portable electronic device provided by the embodiments of the invention, the first screw rod, the sliding rod, and the second screw rod are disposed in coaxial. As such, the size of the entire structure is effectively reduced, and products adopting the hinge structure are thus can be designed to be thin and lightweight. On the other hand, through the linking relationships among the first screw rod, the sliding rod, and the second screw rod, the first machine body and the second machine body may be easily overturned by 360 degrees, and that the portable electronic device may be operated conveniently by the user. 
     To make the above features and advantages of the invention more comprehensible, several embodiments accompanied with drawings are described in detail as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a portable electronic device according to an embodiment of the invention. 
         FIG. 2  is a schematic view of the hinge structure in  FIG. 1 . 
         FIG. 3  is a schematic exploded view of the hinge structure in  FIG. 2 . 
         FIG. 4  is a schematic enlarged view of the region A in  FIG. 2 . 
         FIG. 5  is a schematic enlarged view of the region B in  FIG. 3 . 
         FIG. 6A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a closed state. 
         FIG. 6B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 6A . 
         FIG. 7A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a first state. 
         FIG. 7B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 7A . 
         FIG. 8A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a second state. 
         FIG. 8B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 8A . 
         FIG. 8C  is a schematic local cross-sectional view of the passive module of the portable electronic device in  FIG. 8A  is pushed by external force. 
         FIG. 9  is a schematic view of the portable electronic device in  FIG. 8A  shoots an object to be shot through the passive module. 
         FIG. 10  is diagram showing structural parameters of the portable electronic device in  FIG. 8A . 
         FIG. 11  is a schematic view of a hinge structure according to another embodiment of the invention. 
         FIG. 12A  to  FIG. 12D  are schematic views of motions of a hinge structure according to still another embodiment of the invention. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
       FIG. 1  is a schematic view of a portable electronic device according to an embodiment of the invention. In order to provide clear illustration and better explanation, a process of a second machine body  120  is overturned relative to a first machine body  110  in a first rotating direction R 1  is illustrated with dotted lines in  FIG. 1 . Referring to  FIG. 1 , in the present embodiment, a portable electronic device  100  may be a notebook computer or a combination of a tablet computer and a docking station. The invention is not limited thereto. The portable electronic device  100  includes the first machine body  110 , the second machine body  120 , and a hinge structure  200 . The first machine body  110  and the second machine body  120  are pivoted to each other through the hinge structure  200 . The hinge structure  200  may allow 360 degrees of rotation. Thereby, the first machine body  110  and the second machine body  120  are able to be overturned by 360 degrees. Generally, the first machine body  110  has an input module  112 , and the input module  112  may include a keyboard set and a touch panel. The second machine body  120  has a display module  122 , and the display module  122  may have or may not have touch function according to design requirement. On the other hand, the first machine body  110  has a first upper surface  110   a  and a first lower surface  110   b  opposite to each other, and the input module  112  is located on the first upper surface  110   a . On the other hand, the second machine body  120  has a second upper surface  120   a  and a second lower surface  120   b  opposite to each other, and a display surface  122   a  of the display module  122  is exposed on the second upper surface  120   a.    
       FIG. 2  is a schematic view of the hinge structure in  FIG. 1 .  FIG. 3  is a schematic exploded view of the hinge structure in  FIG. 2 .  FIG. 4  is a schematic enlarged view of the region A in  FIG. 2 .  FIG. 5  is a schematic enlarged view of the region B in  FIG. 3 . In order to provide clear illustration and better explanation, parts of the components in  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5  are depicted in a transparent manner. Referring to  FIG. 1  to  FIG. 5 , in the present embodiment, the hinge structure  200  may include a first connection assembly  260  and a second connection assembly  270  opposite to each other. The first connection assembly  260  includes a first securing member  261 , a second securing member  263 , and a first connection member  265 . The second connection assembly  270  includes a third securing member  271 , a fourth securing member  273 , a second connection member  275 , and a third connection member  277 . 
     Specifically, one of the end portions of the first securing member  261  is secured to the first machine body  110 , and the other end portion of the first securing member  261  is inserted in the first connection member  265 . One of the end portions of the second securing member  263  is secured to the second machine body  120 , and the other end portion of the second securing member  263  is inserted in the first connection member  265 . The first securing member  261  and the second securing member  263  are pivoted to each other. On the other hand, one of the end portions of the third securing member  271  is secured to the first machine body  110 , and the other end portion of the third securing member  271  is inserted in the second connection member  275 . One of the end portions of the fourth securing member  273  is secured to the second machine body  120 , and the other end portion of the fourth securing member  273  is inserted in the second connection member  275 . The third securing member  271  and the fourth securing member  273  are pivoted to each other. Thereby, when the first machine body  110  is at standstill, force may be applied to the second machine body  120 , such that the second securing member  263  and the fourth securing member  273  respectively rotate relative to the first securing member  261  and the third securing member  271 . At the same time, the first connection member  265  and the second connection member  275  respectively rotate along with the second securing member  263  and the fourth securing member  273 , and that the second machine body  120  rotates relative to the first machine body  110 . In other words, the second securing member  263 , the fourth securing member  273 , the first connection member  265 , and the second connection member  275  may rotate along with the second machine body  120  in the first rotating direction R 1  as shown in  FIG. 1 . For instance, the first securing member  261  and the second securing member  263  may be pivoted to each other through a segmental torque hinge structure. Similarly, the third securing member  271  and the fourth securing member  273  may be pivoted to each other through another segmental torque hinge structure. Said two segmental torque hinge structures are respectively disposed in the first connection member  265  and the second connection member  275 . Furthermore, the two segmental torque hinge structures may be configured to secure an angle at which the second machine body  120  unfolds relative to the first machine body  110 . 
     In the present embodiment, the hinge structure  200  may include a first screw rod  210 , a sliding rod  220 , and a second screw rod  230 . The first screw rod  210 , the sliding rod  220 , and the second screw rod  230  are respectively disposed between the first connection assembly  260  and the second connection assembly  270 . Specifically, the first screw rod  210  is connected to the first connection member  265 . The first screw rod  210  comprises a threaded shaft  212 , and the sliding rod  220  is sleeved on the threaded shaft  212 . In other words, the first connection member  265  and the sliding rod  220  are respectively located at two opposite sides of the first screw rod  210 . On the other hand, the second screw rod  230  is sleeved on the sliding rod  220 , and the first screw rod  210  and the second screw rod  230  are respectively located at two opposite sides of the sliding rod  220 . For instance, the first screw rod  210  may be configured with an engagement shaft  216  opposite to the threaded shaft  212 . The first connection member  265  mat be configured with an engagement slot  265   a , and the engagement shaft  216  is engaged with and secured to the engagement slot  265   a  to secure the first screw rod  210  and the first connection member  265 . Thereby, when the first connection member  265  rotates along with the second securing member  263 , the first screw rod  210  also synchronously rotates along with the first connection member  265 . 
     On the other hand, a circumferential surface of the threaded shaft  212  has at least one first helical slot  214 . The sliding rod  220  has a first guiding portion  222  and a second guiding portion  224  opposite to each other, and the first guiding portion  222  is coupled to the first helical slot  214 . In the present embodiment, the sliding rod  220  may be a hollow rod member, and the first guiding portion  222  may be a guide pin. The guide pin penetrates through the sliding rod  220  and is sleeved on a portion of the threaded shaft  212  to be coupled to the first helical slot  214 . On the other hand, the second screw rod  230  may be a hollow rod member, and the second screw rod  230  has at least one second helical slot  232  penetrating through a circumferential wall. The second guiding portion  224  is coupled to the second helical slot  232 . In the present embodiment, the second guiding portion  224  may be a guide pin. The guide pin penetrates through the second helical slot  232  and is secured to a portion of the sliding rod  220  inserted in the second screw rod  230  to be coupled to the second helical slot  232 . In other applicable embodiments, the number of the first helical slot and the number of the second helical slot may respectively be plural. Said first helical slots are equidistantly arranged on the circumferential surface of the threaded shaft, and said second helical slots are equidistantly arranged on the circumferential wall of the second screw rod. Relatively, the number of the first guiding portion is corresponding to the number of said first helical slots, and the number of the second guiding portion is corresponding to the number of said second helical slots. Thereby, when the first screw rod rotates, sliding stability of the sliding rod driven by the first screw rod and rotational stability of the second screw rod driven by the sliding rod may both be enhanced significantly. 
     In the present embodiment, the first helical slot  214  has a first thread  214   a  and a second thread  214   b . The first thread  214   a  is connected to the second thread  214   b , and a helical angle A 1  of the first thread  214   a  is 90 degrees. Thereby, when the first guiding portion  222  is located in the first thread  214   a  and the first screw rod  210  is turned to rotate along the first rotating direction R 1  such that the first thread  214   a  glides relative to the first guiding portion  222 , the sliding rod  220  is not driven by the first screw rod  210 , and that the sliding rod  220  is in a standstill state. On the other hand, a helical angle A 2  of the second thread  214   b  is less than 90 degrees, and the helical angle A 2 , for example, falls between 45 degrees and 65 degrees. Thereby, when the first guiding portion  222  is moved into the second thread  214   b  from the first thread  214   a  and the first screw rod  210  is turned to rotate along the first rotating direction R 1  such that the second thread  214   b  glides relative to the first guiding portion  222 , the first guiding portion  222  is driven by the second thread  214   b  of the first helical slot  214 , and that the sliding rod  220  slides along a sliding direction D 1 . 
     It is worth noting that the first screw rod  210  and the sliding rod  220  share the same central axis AX 1 , and the sliding direction D 1  of the sliding rod  220  is parallel to the central axis AX 1  of the first screw rod  210 . The helical angle A 1  of the first thread  214   a  is the angle included between a helical line HL 1  of the first thread  214   a  and the central axis AX 1  of the first screw rod  210 . The helical angle A 2  of the second thread  214   b  is the angle included between a helical line HL 2  of the second thread  214   b  and the central axis AX 1  of the first screw rod  210 . The helical angle A 1  of the first thread  214   a  is greater than the helical angle A 2  of the second thread  214   b . In other words, in  FIG. 5 , the helical angle A 1  of the first thread  214   a  is calculated starting from the central axis AX 1  of the first screw rod  210  to the helical line HL 1  of the first thread  214   a  in a clockwise direction. The helical angle A 2  of the second thread  214   b  is calculated starting from the central axis AX 1  of the first screw rod  210  to the helical line HL 2  of the second thread  214   b  in the clockwise direction. Moreover, an angle included between an extension line of the first thread  214   a  extending from a random point position and the central axis AX 1  is greater than an angle included between an extension line of the second thread  214   b  extending from a random point position and the central axis AX 1 . 
     When the first guiding portion  222  is driven by the second thread  214   b , as the hinge structure  200  further includes a limiting member  250  disposed to be configured to limit movement of the sliding rod  220 , such that the sliding rod  220  is able to slide relative to the threaded shaft  212  along the sliding direction D 1  without rotating. Referring to  FIG. 1  to  FIG. 5 , the limiting member  250  may include a securing portion  251 , a first limiting portion  252 , a second limiting portion  254 , a third limiting portion  256 , and a third guiding portion  258 . The limiting member  250  is secured to the first machine body  110  through the securing portion  251 . The first limiting portion  252 , the second limiting portion  254 , and the third limiting portion  256  are arranged in a juxtaposed manner. The first limiting portion  252 , the second limiting portion  254 , and the third limiting portion  256  are respectively connected to the securing portion  251 . On the other hand, the second limiting portion  254  is located between the first limiting portion  252  and the third limiting portion  256 . The third guiding portion  258  is located between the first limiting portion  252  and the second limiting portion  254  and is connected to the securing portion  251 . 
     In the present embodiment, as the threaded shaft  212  penetrates through the first limiting portion  252 , rotational stability of the first screw rod  210  is thereby enhanced through the first limiting portion  252 . On the other hand, the sliding rod  220  penetrates through the second limiting portion  254  and may be slidably disposed between the first limiting portion  252  and the third limiting portion  256 . Specifically, the sliding rod  220  further includes a sliding slot  226 . The sliding slot  226  is coupled to the third guiding portion  258 . An extending direction of the sliding slot  226  is parallel to the sliding direction D 1 , and an extending direction of the third guiding portion  258  and the extending direction of the sliding slot  226  are parallel to each other. In other words, when the first guiding portion  222  is driven by the second thread  214   b , as the sliding slot  226  is matched with the third guiding portion  258 , such that the sliding rod  220  is able to slide relative to the threaded shaft  212  along the sliding direction D 1  without rotating. 
     Furthermore, two opposite end portions of the sliding rod  220  inserted in the second limiting portion  254  respectively extend towards the first limiting portion  252  and the third limiting portion  256 . The end portion extending towards the first limiting portion  252  is abutted against the first limiting portion  252 , and the end portion extending towards the third limiting portion  256  is distant from the third limiting portion  256 . In the present embodiment, the second screw rod  230  may comprise a body  236  and a connecting shaft  238 . The body  236  may be a hollow rod member and may be rotatably disposed between the second limiting portion  254  and the third limiting portion  256 . On the other hand, the body  236  is sleeved on the end portion of the sliding rod  220  extending towards the third limiting portion  256 , and two opposite end portions of the body  236  are respectively abutted against the second limiting portion  254  and the third limiting portion  256 . The connecting shaft  238  has a first end portion  238   a  and a second end portion  238   b  opposite to each other. The first end portion  238   a  penetrates through the third limiting portion  256 , and the first end portion  238   a  further penetrates into the body  236  to be secured onto the body  236 . When the sliding rod  220  slides away from the first limiting portion  252  along the sliding direction D 1 , the second helical slot  232  located on the body  236  is driven by the second guiding portion  224 . As the body  236  is limited between the second limiting portion  254  and the third limiting portion  256 , and the first end portion  238   a  is inserted in the third limiting portion  256 , as such, the second screw rod  230  is able to rotate relative to the sliding rod  220  without sliding. 
     Specifically, when the first screw rod  210  rotates along the first rotating direction R 1  such that the first guiding portion  222  is moved into the second thread  214   b , the sliding rod  220  is driven by the first screw rod  210  to slide away from the first limiting portion  252  along the sliding direction D 1 . At the same time, the second screw rod  230  is driven by the sliding rod  220  to rotate along the second rotating direction R 2  opposite to the first rotating direction R 1 . As a helical direction of the second helical slot  232  is configured to be opposite to a helical direction of the first helical slot  214 , and thereby, when the sliding rod  220  is driven by the first screw rod  210  rotating in the first rotating direction R 1 , the sliding rod  220  is able to enable the second screw rod  230  to rotate along the second rotating direction R 2  opposite to the first rotating direction R 1 . 
     In the present embodiment, a helical angle A 3  of the second helical slot  232  is less than 90 degrees, and the helical angle A 3 , for example, falls between 35 degrees and 55 degrees. It is worth noting that the second screw rod  230 , the first screw rod  210 , and the sliding rod  220  share the same central axis AX 1 . The helical angle A 3  of the second helical slot  232  is the angle included between a helical line HL 3  of the second helical slot  232  and the central axis AX 1  of the first screw rod  210 . The helical angle A 1  of the first thread  214   a  of the first helical slot  214  and the helical angle A 2  of the second thread  214   b  are both greater than the helical angle A 3  of the second helical slot  232 . In other words, in  FIG. 5 , the helical angle A 3  of the second helical slot  232  is calculated starting from the central axis AX 1  of the first screw rod  210  to the helical line HL 3  of the second helical slot  232  in a counter-clockwise direction. 
     For instance, when the helical angle A 2  of the second thread  214   b  falls between 45 degrees and 65 degrees, the helical angle A 3  of the second helical slot  232  falls between 35 degrees and 45 degrees, and the helical angle A 3  of the second helical slot  232  is less than 45 degrees, i.e., 45&lt;A 2 &lt;65 and 35&lt;A 3 &lt;45. When the helical angle A 2  of the second thread  214   b  falls between 45 degrees and 65 degrees, and when the helical angle A 2  of the second thread  214   b  is greater than 45 degrees, the helical angle A 3  of the second helical slot  232  falls between 35 degrees and 45 degrees, i.e., 45&lt;A 2 &lt;65 and 35&lt;A 3 &lt;45. When the helical angle A 2  of the second thread  214   b  falls between 55 degrees and 65 degrees, and when the helical angle A 2  of the second thread  214   b  is greater than 55 degrees, the helical angle A 3  of the second helical slot  232  falls between 35 degrees and 55 degrees, i.e., 55&lt;A 2 &lt;65 and 35&lt;A 3 &lt;55. When the helical angle A 2  of the second thread  214   b  falls between 55 degrees and 65 degrees, the helical angle A 3  of the second helical slot  232  falls between 35 degrees and 55 degrees, and the helical angle A 3  of the second helical slot  232  is less than 55 degrees, i.e., 55&lt;A 2 &lt;65 and 35&lt;A 3 &lt;55. Through the foregoing arrangement, the helical angle A 1  of the first thread  214   a  of the first helical slot  214  provided by the present embodiment and the second helical angle A 2  of the second thread  214   b  are both greater than the helical angle A 3  of the second helical slot  232 . 
     As shown in  FIG. 5 , a helical length of the first helical slot  214  is greater than a helical length of the second helical slot  232 . In other words, a total length of a threaded path of the first helical slot  214  is greater than a total length of a threaded path of the second helical slot  232 . 
     Referring to  FIG. 2  to  FIG. 5 , the hinge structure  200  further includes a passive module  240  having a lens  242 . The second end portion  238   b  of the connecting shaft  238  of the second screw rod  230  is inserted in the passive module  240 , and the second screw rod  230  is located between the first screw rod  210  and the passive module  240 . On the other hand, a third connection member  277  may be a hollow rod member. The third connection member  277  is secured to the first machine body  110 , and the passive module  240  is pivoted to the third connection member  277  through a pivot axis  246 . In the present embodiment, the passive module  240  is located between the second screw rod  230  and the third connection member  277 , and two opposite end portions of the passive module  240  are respectively pivoted to the second screw rod  230  and the third connection member  277 . In other words, the third connection member  277  is located between the passive module  240  and the second connection member  275 . A signal trace or an electricity trace may penetrate through the second connection member  275  and the third connection member  277  and may extend to the position of the passive module  240  to be electrically connected to the passive module  240 . 
     In the present embodiment, the passive module  240  may be magnetically connected to (or magnetically secured to) the second screw rod  230 , such that the passive module  240  is able to rotate along with the second screw rod  230  and the connecting shaft  238 . On the other hand, force may be applied by a user to the passive module  240  to remove the magnetic connection relationship between the passive module  240  and the second screw rod  230 , such that the passive module  240  rotates relative to the second screw rod  230  and the third connection member  277 . Particularly, the second screw rod  230  is configured with a second magnetic member  234 , and the second magnetic member  234  may be disposed on the connecting shaft  238 . The passive module  240  is configured with a first magnetic member  244 . For instance, the second magnetic member  234  and the first magnetic member  244  may form a combination of two magnets magnetically attracted to each other or may form a combination of a magnet and a magnetic metal. 
     Relative locations, connecting relationships, and linking relationships among the first screw rod  210 , the sliding rod  220 , the second screw rod  230 , and the passive module  240  are described above. Corresponding motions generated by the passive module  240  when the second machine body  120  is overturned relative to the first machine body  110  through the hinge structure  200  is described as follows. 
       FIG. 6A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a closed state.  FIG. 6B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 6A .  FIG. 7A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a first state.  FIG. 7B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 7A . Referring to  FIG. 6A  and  FIG. 6B , before the portable electronic device  100  is transformed to the open state as shown in  FIG. 1 , the portable electronic device  100  is in the closed state. At this time, the first guiding portion  222  of the sliding rod  220  is located in the first thread  214   a . An angle included between a shooting axis  242   a  of the lens  242  of the passive module  240  and a reference line L parallel to the first upper surface  110   a  may be 65 degrees. 
     Referring to  FIG. 1 ,  FIG. 2 , and  FIG. 6A  to  FIG. 7B , when the first machine body  110  is at standstill and the second machine body  120  is enabled to rotate relative to the first machine body  110  along the first rotating direction R 1  to be transformed from the closed state shown in FIG.  6 A to the first state shown in  FIG. 7A , the first upper surface  110   a  of the first machine body  110  and the second upper surface  120   a  of the second machine body  120  are opposite to each other. Moreover, an angle included between the first upper surface  110   a  and the second upper surface  120   a  is, for example, 120 degrees. On the other hand, the first screw rod  210  rotates along the first rotating direction R 1  such that the first thread  214   a  glides relative to the first guiding portion  222 , as the helical angle A 1  of the first thread  214   a  is 90 degrees, and thereby, the sliding rod  220  does not slide to drive the second screw rod  230  and the passive module  240  to rotate. As such, the angle included between the shooting axis  242   a  of the lens  242  of the passive module  240  and the reference line L is maintained at 65 degrees. When the first screw rod  210  continues to rotate along the first rotating direction R 1 , the second thread  214   b  glides close to the first guiding portion  222 , such that the first guiding portion  222  is enabled to move to a juncture between the first thread  214   a  and the second thread  214   b . In the present embodiment, a central angle of the first thread  214   a , for example, falls between 115 rad and 125 rad. Thereby, when the portable electronic device  100  is transformed from the closed state shown in  FIG. 6A  to the first state shown in  7 A, the sliding rod  220 , the second screw rod  230 , and the passive module  240  are maintained to be at standstill. As such, when the portable electronic device  100  is in the first state shown in  FIG. 7A , the lens  242  of the passive module  240  in the first state is able to be exposed on an opening space Si defined by the first upper surface  110   a  and the second upper surface  120   a . Moreover, the shooting axis  242   a  of the lens  242  is set to face the user. 
       FIG. 8A  is a schematic local cross-sectional view of the portable electronic device in  FIG. 1 , and the portable electronic device is in a second state.  FIG. 8B  is a schematic local perspective view corresponding to the hinge structure of the portable electronic device in  FIG. 8A . Referring to  FIG. 1 ,  FIG. 2 , and  FIG. 7A  to  FIG. 8B , the second machine body  120  is enabled to rotate continuously relative to the first machine body  110  along the first rotating direction R 1 , and the first screw rod  210  rotates along with the second machine body  120  along the first rotating direction R 1 , such that the first guiding portion  222  is moved into the second thread  214   b  from the juncture between the first thread  214   a  and the second thread  214   b . As the helical angle A 2  of the second thread  214   b  is less than 90 degrees, and thereby, when the second thread  214   b  glides relative to the first guiding portion  222 , the first guiding portion  222  is driven by the first thread  214   b  and that the sliding rod  220  slides along the sliding direction D 1 . At the same time, the second helical slot  232  is driven by the second guiding portion  224  of the sliding rod  220  which is sliding, such that the second screw rod  230  rotates along the second rotating direction R 2  different from the first rotating direction R 1 . As the passive module  240  is magnetically secured to the second screw rod  230 , such that the passive module  240  may synchronously rotate along with the second screw rod  230 . 
     When the portable electronic device  100  is transformed from the first state shown in  FIG. 7A  to the second state shown in  FIG. 8A , an angle included between the second upper surface  120   a  of the second machine body  120  and the first upper surface  110   a  of the first machine body  110  continues to expand starting from 120 degrees. Moreover, the passive module  240  continues to synchronously rotate along with the second screw rod  230 . When the angle included between the second upper surface  120   a  of the second machine body  120  and the first upper surface  110   a  of the first machine body  110  is 160 degrees, the passive module  240  rotates by 65 degrees along the second rotating direction R 2 , and that the angle included between the shooting axis  242   a  of the lens  242  and the reference line L is changed to 0 degree. When the angle included between the first upper surface  110   a  and the second upper surface  120   a  is 180 degrees, the passive module  240  rotates by 73 degrees along the second rotating direction R 2 , and that the angle included between the shooting axis  242   a  of the lens  242  and the reference line L is changed to 8 degrees. When the angle included between the first upper surface  110   a  and the second upper surface  120   a  is 200 degrees, the passive module  240  rotates by 95 degrees along the second rotating direction R 2 , and that the angle included between the shooting axis  242   a  of the lens  242  and the reference line L is changed to 30 degrees. As the first securing member  261  and the second securing member  263  are respectively secured to the first machine body  110  and the second machine body  120 , and the first securing member  261  and the second securing member  263  are pivoted to each other through the segmental torque hinge structure, such that when the second machine body  120  rotates relative to the first machine body  110  along the first rotating direction R 1 , an angle included between the second machine body  120  and the first connection member  265  is maintained at 120 degrees through the segmental torque hinge structure. 
     Next, the second machine body  120  is enabled to rotate continuously relative to the first machine body  110  along the first rotating direction R 1 , and the angle included between the first upper surface  110   a  and the second upper surface  120   a  thus expands from 200 degrees to 277 degrees. When the angle included between the first upper surface  110   a  and the second upper surface  120   a  is 277 degrees, the passive module  240  rotates by 111 degrees in the second rotating direction R 2 , and that the angle included between the shooting axis  242   a  of the lens  242  and the reference line L is changed to 46 degrees. When the angle included between the first upper surface  110   a  and the second upper surface  120   a  expands from 200 degrees to 277 degrees, the passive module  240  continues to rotate along the second rotating direction R 2 . Moreover, the second securing member  263  overcomes the torque force of the segmental torque hinge structure, such that an angle included between the second securing member  263  and the first connection member  265  expands from 120 degrees to 199 degrees. At the same time, the angle included between the second machine body  120  and the first connection member  265  expands from 120 degrees to 199 degrees. 
     When the portable electronic device  100  is in the second state, the first lower surface  110   b  of the first machine body  110  and the second lower surface  120   b  of the second machine body  120  are facing opposite to each other. At this time, an angle included between the first lower surface  110   b  and the second lower surface  120   b  is 68 degrees to define an image pickup space PS to contain an object  20  to be shot (shown in  FIG. 9 ). Moreover, the lens  242  of the passive module  240  is exposed in the image pickup space PS. 
       FIG. 8C  is a schematic local cross-sectional view of the passive module of the portable electronic device in  FIG. 8A  is pushed by external force. Referring to  FIGS. 8A and 8C , in the present embodiment, the portable electronic device  100  further includes a third magnetic member  202 . The third magnetic member  202  is secured to the second machine body  120  and is disposed close to a side of the hinge structure  200 . Specifically, the third magnetic member  202  is disposed corresponding to the first magnetic member  244 , and the first magnetic member  244  and the third magnetic member  202  form a combination of magnets magnetically repulsive to each other. When force is applied by a user to the passive module  240  to remove the magnetic connection relationship between the passive module  240  and the second screw rod  230  (i.e., the magnetic connection relationship between the first magnetic member  244  and the second magnetic member  234 ), the passive module  240  is able to rotate relative to the second screw rod  230  and the third connection member  277 . As such, the lens  242  of the passive module  240  is turned, and the lens  242  is moved out of the image pickup space PS as shown in  FIG. 8C . 
     On the other hand, the repulsive force between the third magnetic member  202  and the first magnetic member  244  is able to drive the passive module  240  to return to the original position, meaning that the first magnetic member  244  and the second magnetic member  234  are aligned with each other, and the passive module  240  is magnetically secured to the second screw rod  230 . For instance, when the third magnetic member  202  rotates along with the second machine body  120  and is moved close to the first magnetic member  244 , the repulsive force between the third magnetic member  202  and the first magnetic member  244  is able to drive the passive module  240  to rotate. Once the first magnetic member  244  is moved close to the second magnetic member  234 , a multiplier effect created by the repulsive force between the first magnetic member  244  and the second magnetic member  234  along with the above-mentioned repulsive force is generated, and that the passive module  240  is enabled to return to the original position more rapidly. On the other hand, when force is applied to the passive module  240  by the user to enable the passive module  240  to rotate, when the first magnetic member  244  on the passive module  240  is moved close to the third magnetic member  202 , the repulsive force between the third magnetic member  202  and the first magnetic member  244  is able to drive the passive module  240  to rotate. Once the first magnetic member  244  is moved close to the second magnetic member  234 , a multiplier effect created by the repulsive force between the first magnetic member  244  and the second magnetic member  234  along with the above-mentioned repulsive force is generated, and that the passive module  240  is enabled to return to the original position more rapidly. 
       FIG. 9  is a schematic view of the portable electronic device in  FIG. 8A  shoots an object to be shot through the passive module.  FIG. 10  is diagram showing structural parameters of the portable electronic device in  FIG. 8A . Referring to  FIG. 9  and  FIG. 10 , the portable electronic device  100  in the second state may be placed on a working platform  10 , such that a long lateral side of the first machine body  110  and a long lateral side of the second machine body  120  lean against the working platform  10 . At this time, the object  20  to be shot may be placed on the working platform  10  by the user and may be located in the image pickup space PS. Furthermore, the object  20  to be shot is placed between the first lower surface  110   b  and the second lower surface  120   b , and the lens  242  of the passive module  240  faces the object  20  to be shot. 
     In short, in the hinge structure  200  provided by the present embodiment, the first screw rod  210 , the sliding rod  200 , and the second screw rod  230  are disposed in coaxial. As such, the size of the entire structure is effectively reduced, and products are able to be designed to be thin and lightweight. On the other hand, when the first machine body  110  and the second machine body  120  are overturned, the passive module  240  magnetically secured to the second screw rod  230  may synchronously rotate along with the second screw rod  230  through the linking relations among the first screw rod  210 , the sliding rod  220 , and the second screw rod  230 . As such, when the portable electronic device  100  is transformed to the second state shown in  FIG. 8A , the object  20  to be shot placed between the first lower surface  110   b  of the first machine body  110  and the second lower surface  120   b  of the second machine body  120  may be shot through the lens  242  of the passive module  240 , and that the portable electronic device  100  may be operated conveniently by the user. 
     Referring to  FIG. 9  and  FIG. 10 , an included angle between the first lower surface  110   b  of the first machine body  110  and the second lower surface  120   b  of the second machine body  120  is α, an included angle between the first lower surface  110   b  of the first machine body  110  and the working platform  10  is β, an included angle between the second lower surface  120   b  of the second machine body  120  is γ, and an image pickup angle of the passive module  240  is ω. For instance, a length of a short lateral side of the first machine body  110  may be Y 1 , and a length of a short lateral side of the second machine body  120  may be Y 2 . The shooting axis  242   a  of the lens  242  of the passive module  240  is, for example, perpendicular to the working platform  10 , and a vertical distance between the lens  242  and the working platform  10  is H. On the other hand, the projection point of the shooting axis  242   a  projected on the working platform  10  is P, a horizontal distance measuring from a point at which the long lateral side of the first machine body  110  leans against the working platform  10  to the projection point  10  is X 1 , and a horizontal distance measuring from a point at which the long lateral side of the second machine body  120  leans against the working platform  10  to the projection point P is X 2 . 
     The following calculation formulas are thus obtained according to trigonometric function: sin β=H/Y 1 , sin γ=H/Y 2 , cos β=X 1 /Y 1 , cos γ=X 2 /Y 2 , X 1 =Y 1 x cos β, X 2 =Y 2 x cos γ, H=Y 1 x sin β, H=Y 2 *x sin γ, β=sin −1  x(H/Y 1 ), and γ=sin −1  x(H/Y 2 ). On the other hand, the image pickup angle ω is generally greater than the included angle α and may be presented by the calculation formula as follows: ω&gt;180−(β+γ). Alternatively, the following calculation formula may also be obtained through converting the foregoing calculation formulas: ω&gt;180−(sin −1  x(H/Y 1 )+sin −1  x(H/Y 2 )). Thereby, an image pickup range of the lens  242  may exceed a sum of the horizontal distance X 1  and the horizontal distance X 2 . Furthermore, the image pickup range of the lens  242  may be converted according to the trigonometric function and through parameters such as the vertical distance H and the image pickup angle ω. A favorable image pickup range refers to a range covering the long lateral side of the first machine body  110  and the long lateral side of the second machine body  120 , or a range exceeding the long lateral side of the first machine body  110  and the long lateral side of the second machine body  120 . Thereby, the overall object  20  to be shot is located in the image pickup space PS, and a size of the overall object  20  to be shot does not exceed a sum of the long lateral side of the first machine body  110  (or the long lateral side of the second machine body  120 ) and the sum of the horizontal distance X 1  and the horizontal distance X 2 . As such, the overall object  20  to be shot falls in the range of the image pickup range of the lens  242 , and the overall object  20  to be shot can be shot. 
     For instance, the object  20  to be shot may be an A4 document. When the A4 document is placed, two long lateral sides opposite to each other of the A4 document are required to be placed respectively parallel to the long lateral side of the first machine body  110  and the long lateral side of the second machine body  120 . The content of the A4 document may be shot by the passive module  240  through the lens  242 , and an image obtained through shooting is displayed on the display surface  122   a  of the display module  122 . As a length of any of the long lateral side of the A4 document is less than or equal to a length of the long lateral side of the first machine body  110  or a length of the long lateral side of the second machine body  120 , and thereby, the overall A4 document falls within the image pickup range of the lens  242 . In one of the embodiments, the image pickup angle ω of the lens  242  may be greater than or equal to 88 degrees. Moreover, the included angle between the first upper surface  110   a  of the first machine body  110  and the second upper surface  120   a  of the second machine body  120  may be 292 degrees, and thus, the corresponding included angle α is 68 degrees. On the other hand, the included angle β may be 54 degrees, the included angle γ may be 58 degrees, and the vertical distance H may be 175 mm. Accordingly, the sum of the horizontal distance X 1  and the horizontal distance X 2  is converted to be 236 mm. In the rest of the embodiments, the foregoing values may be adjusted according to actual requirements. The invention is not limited thereto. 
     In the present embodiment, as the image pickup angle ω is greater than the included angle α, such that the image shot by the lens  242  includes portions of the first machine body  110  and the second machine body  120  falling within the image pickup range of the lens  242 . If the passive module  240  is set to be in a shooting mode with aspect ratio of 16:9, the image shot by the lens  242  may be cut to cut off unnecessary portions of the image (e.g., the first machine body  110  and the second machine body  120 ). As such, the complete image of the object  20  to be shot is obtained. 
       FIG. 11  is a schematic view of a hinge structure according to another embodiment of the invention. Referring to  FIG. 11 , a hinge structure  300  may be configured to connect the first machine body  110  and the second machine body  120  shown in  FIG. 1 , such that the first machine body  110  and the second machine body  120  may be overturned by 360 degrees. Specifically, the hinge structure  300  includes a sun gear G 1 , a plurality of planetary gears G 2 , and an annular gear G 3 . The sun gear G 1  is coupled to the planetary gears G 2 , and the planetary gears G 2  are coupled to the annular gear G 3 . When the sun gear G 1  rotates along the first rotating direction R 1 , the planetary gears G 2  are driven to rotate along the second rotating direction R 2  opposite to the first rotating direction R 1 . The annular gear G 3  is driven by the planetary gears G 2  to rotate along the second rotating direction R 2 . For instance, the passive module  240  in the foregoing embodiments may be rotatably connected to the annular gear G 3  to synchronously rotate along with the annular gear G 3 . 
       FIG. 12A  to  FIG. 12D  are schematic views of motions of a hinge structure according to still another embodiment of the invention. Referring to  FIG. 12A  to  FIG. 12D , a hinge structure  400  may be configured to connect the first machine body  110  and the second machine body  120  shown in  FIG. 1 , such that the first machine body  110  and the second machine body  120  may be overturned by 360 degrees. Specifically, the hinge structure  400  includes a first motion member  410  and a second motion member  420 . The second motion member  420  is configured with an elastic member  422 , and the second motion member  420  is located between the first motion member  410  and the elastic member  422 . In the present embodiment, when the second machine body  120  rotates relative to the first machine body  110  as shown in  FIG. 1 , the first motion member  410  may be driven by the second machine body  120  as shown in  FIG. 1  to move close to the second motion member  420  along the sliding direction D 2  and is abutted against the second motion member  420 . A first sawtooth structure  412  of the first motion member  410  and a second sawtooth structure  424  in the second motion member  420  disposed corresponding to the first sawtooth structure  412  are matched sawtooth structures. The first sawtooth structure  412  may be a combination combining a plurality of inclined surfaces, and the second sawtooth structure  424  may be a combination combining a plurality of flat surfaces and inclined surfaces. Thereby, when the second sawtooth structure  424  is further pushed by the first sawtooth structure, the forced second motion member  420  is able to rotate along a rotating direction R 3 . For instance, the passive module  240  in the foregoing embodiments may be rotatably connected to the second motion member  420  to synchronously rotate along with the second motion member  420 . 
     On the other hand, when the first motion member  410  moves back and forth along the sliding direction D 2  and the opposite direction of the sliding direction D 2 , the second motion member  420  is continuously pushed by the first motion member  410  to rotate along the rotating direction R 3 . For instance, the elastic member  422  may be a torsion spring. The torsion spring accumulates elastic potential energy when the second motion member  420  rotates. The second elastic member  420  may rotate along a direction opposite to the rotating direction R 3  to return back to the original state when the elastic potential energy is released. 
     In view of the foregoing, in the hinge structure provided by the embodiments of the invention, the first screw rod, the sliding rod, and the second screw rod are disposed in coaxial. As such, the size of the entire structure is effectively reduced, and products adopting the hinge structure are thus can be designed to be thin and lightweight. On the other hand, when the first machine body and the second machine body are overturned, the passive module magnetically secured to the second screw rod may synchronously rotate along with the second screw rod through the linking relations among the first screw rod, the sliding rod, and the second screw rod. As such, when the portable electronic device is transformed to the second state, the object to be shot placed between the first lower surface of the first machine body and the second lower surface of the second machine body may be shot through the lens of the passive module, and that the portable electronic device may be operated conveniently by the user. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention covers modifications and variations of this disclosure provided that they fall within the scope of the following claims and their equivalents.