Patent Publication Number: US-8536472-B2

Title: Rotary switch mechanism

Description:
FIELD OF THE INVENTION 
     The present invention relates to a rotary switch mechanism, and more particularly to a rotary switch mechanism with a push button function. 
     BACKGROUND OF THE INVENTION 
     Generally, a rotary switch mechanism is a mechanism that is rotated in either a clockwise direction or an anti-clockwise direction. For example, the rotary switch mechanism is usually installed on an acoustical device for adjusting sound volume or changing broadcast channels. 
     With the increasing development of science and technology, the applications of the rotary switch mechanism are gradually expanded. Generally, as shown in  FIG. 1 , the rotary switch mechanism  10  is installed on a keyboard device  1  of a computer system in order to enhance the function of the keyboard device  1 . By operating the rotary switch mechanism  10 , a sound volume adjustment command of a video player program, a text file proportional scale command or an image file proportional scale command in the computer system may be executed. 
     Hereinafter, the internal structures and the operating principles of a conventional rotary switch mechanism will be illustrated with reference to  FIGS. 2 and 3 .  FIG. 2  is a schematic exploded view illustrating a conventional rotary switch mechanism.  FIG. 3  is a schematic perspective view illustrating the outward appearance of the conventional rotary switch mechanism. As shown in  FIGS. 2 and 3 , the conventional rotary switch mechanism  2  comprises a circuit board  20 , a rotatable member  21 , a push button  22 , a rotary switch  23 , an elastic element  24 , a first push switch  25 , a second push switch  26 , a third push switch  27 , a fourth push switch  28  and a fifth push switch  29 . 
     The circuit board  20  has a mounting aperture  201 . The rotatable member  21  has plural projecting parts  211 , which are arranged at the periphery of the rotatable member  21 . The push button  22  comprises a central button part  221 , a ring-shaped part  222  and a fixing part  223 . The ring-shaped part  222  is connected with the central button part  221  and arranged around the central button part  221 . The fixing part  223  is disposed on the ring-shaped part  222 . After the fixing part  223  is engaged with the mounting aperture  201  of the circuit board  20 , the push button  22  is fixed on the circuit board  20 . The five push switches  25 ,  26 ,  27 ,  28  and  29 , the rotary switch  23  and the elastic element  24  are all disposed on the circuit board  20 . In addition, the five push switches  25 ,  26 ,  27 ,  28  and  29  are disposed under the push button  22 . The rotary switch  23  is arranged beside the push button  22 . In addition, the rotary switch  23  has a handle part  231 . 
     Upon rotation of the rotatable member  21  of the rotary switch mechanism  2 , the plural projecting parts  211  of the rotatable member  21  are synchronously rotated. As the projecting parts  211  are rotated, the projecting parts  211  interact with the handle part  231  of the rotary switch  23  so as to swing the handle part  231 . As the handle part  231  is swung, a rotation signal is generated. In response to the rotation signal, a specified command (e.g. the sound volume adjustment command) is executed. Moreover, upon rotation of the rotatable member  21 , the handle part  231  may be swung in either a clockwise direction or an anti-clockwise direction to generate two different rotation signals. According to the two rotation signals, a sound volume increasing command and a sound volume decreasing command are respectively executed. On the other hand, during the process of rotating the rotatable member  21 , the elastic element  24  is contacted with plural notches (not shown) that are arranged at the inner periphery of the bottom side of the rotatable member  21  so as to result in an elastic force. Due to the elastic force, the rotation of the rotatable member  21  results in a multi-step rotating feel to the user. 
     By pressing the central button part  221  of the conventional rotary switch mechanism  2 , the central button part  221  is moved downwardly to push against the first push switch  25  under the central button part  221 . As a result, the first push switch  25  is triggered to generate a first triggering signal. In response to the first triggering signal, another specified command (e.g. a clicking and selecting command) is executed. By pressing the ring-shaped part  222  of the conventional rotary switch mechanism  2 , the second push switch  26  under the ring-shaped part  222  is triggered to generate a second triggering signal. In response to the second triggering signal, another specified command (e.g. a text file proportional scale-up command) is executed. By pressing the ring-shaped part  222  of the conventional rotary switch mechanism  2 , the third push switch  27  is triggered to generate a third triggering signal. In response to the third triggering signal, another specified command (e.g. a text file proportional scale-down command) is executed. Moreover, by triggering the fourth push switch  28  and the fifth push switch  29 , different commands (e.g. an image file proportional scale-up command and an image file proportional scale-down command) are executed. The operations of the fourth push switch  28  and the fifth push switch  29  are similar to those of the second push switch  26  and the third push switch  27 , and are not redundantly described herein. 
     From the above discussions, the conventional rotary switch mechanism  2  may be operated to execute at most four commands. That is, the sound volume adjustment command is executed by rotating the rotatable member  21 , the clicking and selecting command is executed by pressing the central button part  221 , the text file proportional scale command is executed by pressing the ring-shaped part  222 , and the image file proportional scale command is executed by pressing the ring-shaped part  222 . The conventional rotary switch mechanism  2 , however, still has some drawbacks. For example, since the conventional rotary switch mechanism  2  can execute at most four commands, the conventional rotary switch mechanism  2  fails to meet the user&#39;s requirements. In addition, since the rotatable member  21  and the push button  22  of the conventional rotary switch mechanism  2  are in contact with each other, upon rotation of the rotatable member  21 , the jointing regions between the rotatable member  21  and the push button  22  may rub against each other. Since a long-termed use may abrade the structure of the conventional rotary switch mechanism  2 , the use life of the conventional rotary switch mechanism  2  is shortened. Moreover, since the five push switches  25 ,  26 ,  27 ,  28  and  29  of the conventional rotary switch mechanism  2  are disposed under the rotatable member  21 , if the force exerted on the rotatable member  21  is unevenly distributed during the process of rotating the rotatable member  21 , the rotatable member  21  is readily tilted. Since the ring-shaped part  222  of the push button  22  is also tilted, the possibility of erroneously touching the push switches  25 ,  26 ,  27 ,  28  and  29  will be increased. Under this circumstance, an erroneous operation problem possibly occurs. 
     SUMMARY OF THE INVENTION 
     The present invention provides rotary switch mechanism capable of executing more function commands. 
     The present invention also provides a rotary switch mechanism to reduce the possibility of the erroneous operation problem. 
     In accordance with an aspect of the present invention, there is provided a rotary switch mechanism. The rotary switch mechanism includes a main circuit board, a base, a first rotatable member, a first signal-generating module, a second rotatable member, a second signal-generating module and a push button. The base is disposed on the main circuit board. The first rotatable member is disposed on the base and rotatable with respect to the base. The first signal-generating module is mounted on the main circuit board. In response to rotation of the first rotatable member, the first signal-generating module generates a first rotation signal. The second rotatable member is disposed on the base, arranged around the first rotatable member, and rotatable with respect to the base. The second signal-generating module is mounted on the main circuit board. In response to rotation of the second rotatable member, the second signal-generating module generates a second rotation signal. The push button is disposed within the first rotatable member, and comprising a pushing surface. The push button includes an optical finger navigation module and a push switch. The optical finger navigation module is disposed within the push button and arranged under the pushing surface of the push button for detecting a motion of a user&#39;s finger on the pushing surface. In response to the motion of the user&#39;s finger, the optical finger navigation module generates a motion signal. The push switch is disposed under the optical finger navigation module. When the push button is pressed down, the push switch is triggered to generate a triggering signal. 
     In an embodiment, the first signal-generating module includes a magnetic ring and a reed sensor assembly. The magnetic ring is disposed on a lower portion of the first rotatable member, and synchronously rotated with the first rotatable member. The reed sensor assembly is mounted on the main circuit board and arranged in the vicinity of the magnetic ring for detecting rotation of the magnetic ring, thereby generating the first rotation signal. 
     In an embodiment, the magnetic ring includes plural N-pole regions, plural S-pole regions and plural spacer regions. One side of each spacer region is adjacent to an N-pole region, and the other side of each spacer region is adjacent to an S-pole region. 
     In an embodiment, the reed sensor assembly includes a first reed sensor and a second reed sensor. The first reed sensor is disposed under the N-pole region or the S-pole region to detect a magnetic field change between the N-pole region and the S-pole region. The second reed sensor is disposed under the spacer region to detect a magnetic field change between the N-pole region and the S-pole region. 
     In an embodiment, the second signal-generating module includes an idle wheel and an encoder. The idle wheel is disposed on the base, and includes a rotating shaft and plural idle wheel saw-toothed parts. The plural idle wheel saw-toothed parts are engaged with plural rotatable member saw-toothed parts of the second rotatable member, so that the idle wheel is synchronously rotated with the second rotatable member. The encoder is mounted on the main circuit board. The rotating shaft of the idle wheel is inserted into the encoder. In response to rotation of the idle wheel, the second rotation signal is generated by the encoder. 
     In an embodiment, the push button further includes a push button holder, an elastic element and a push button circuit board. The push button holder is disposed on the first rotatable member and movable upwardly and downwardly with respect to the first rotatable member. The push button holder includes a central sleeve and a central hole. The central sleeve is disposed under the push switch. The central hole is disposed in a center of the central sleeve. The elastic element is sheathed around the central sleeve and sustained against the first rotatable member for providing an elastic force. In response to the elastic force, the push button holder is movable upwardly. The push button circuit board is disposed on the push button holder. The optical finger navigation module is disposed on a first surface of the push button circuit board. The push switch is disposed on a second surface of the push button circuit board. 
     In an embodiment, the first rotatable member further includes a light guide structure, plural perforations and a triggering part. The light guide structure is disposed within the first rotatable member. A top portion of the light guide structure is exposed outside the first rotatable member and arranged around the pushing surface of the push button. After the push button holder is penetrated through the plural perforations, the push button holder is engaged with the light guide structure. The triggering part is arranged between the plural perforations, penetrated through the central hole and arranged in the vicinity of the push switch. When the push button is pressed down to push against the push switch, the triggering signal is generated by the push switch. 
     In an embodiment, the rotary switch mechanism further includes plural light emitting diodes, which are mounted on the main circuit board for emitting plural light beams. After the plural light beams are directed to the light guide structure, the light beams are guided by the light guide structure and projected onto a region between the push button and the first rotatable member. 
     In an embodiment, the light guide structure and the triggering part are integrally formed. 
     In an embodiment, the optical finger navigation module includes a light source, a reflective mirror, a focusing lens and a motion sensor. The light source is used for emitting a light beam to be projected on the pushing surface of the push button. The reflective mirror is used for reflecting the light beam. The focusing lens is used for focusing the light beam that is reflected by the user&#39;s finger. The motion sensor is used for receiving the light beam, and generating the motion signal according to the light beam. 
     The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic perspective view illustrating the outward appearance of a rotary switch mechanism installed on a keyboard device according to the prior art; 
         FIG. 2  is a schematic exploded view illustrating a conventional rotary switch mechanism; 
         FIG. 3  is a schematic perspective view illustrating the outward appearance of the conventional rotary switch mechanism; 
         FIG. 4  is a schematic perspective view illustrating the outward appearance of a rotary switch mechanism according to an embodiment of the present invention; 
         FIG. 5  is a schematic cutaway view illustrating a rotary switch mechanism according to an embodiment of the present invention; 
         FIG. 6  is a schematic cutaway view illustrating the rotary switch mechanism of  FIG. 5  and taken along another viewpoint; 
         FIG. 7  is a schematic cross-sectional view illustrating an optical finger navigation module of a rotary switch mechanism according to an embodiment of the present invention; 
         FIG. 8  is a schematic perspective view illustrating the outward appearance of the rotary switch mechanism of  FIG. 4  and taken along another viewpoint; and 
         FIG. 9  is a schematic top view illustrating a magnetic ring and a reed sensor assembly of a rotary switch mechanism according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 4  is a schematic perspective view illustrating the outward appearance of a rotary switch mechanism according to an embodiment of the present invention. As shown in  FIG. 4 , the rotary switch mechanism  3  comprises a main circuit board  30 , a base  31 , a first rotatable member  32 , a second rotatable member  34  and a push button  36 . The base  31  is disposed on the main circuit board  30 . The first rotatable member  32  is disposed on the base  31 . The second rotatable member  34  is disposed on the base  31  and arranged around the first rotatable member  32 . In addition, the second rotatable member  34  is rotatable with respect to the base  31 . The push button  36  is disposed within the first rotatable member  32 . In addition, the push button  36  has a pushing surface  361 . The user&#39;s finger is movable on the pushing surface  361  of the push button  36 . In the rotary switch mechanism  3 , the outer surface of the first rotatable member  32  is a smooth surface. In addition, the outer surface of the second rotatable member  34  has plural pyramidal structures  341 . In a case that the user&#39;s fingers is contacted with the first rotatable member  32  and the second rotatable member  34 , these two rotatable members  32  and  34  can be obviously recognized by the user&#39;s fingers through the pyramidal structures  341 . Under this circumstance, the possibility of erroneously touching the two rotatable members  32  and  34  will be reduced. 
     Hereinafter, the internal portion of the rotary switch mechanism  3  of the present invention will be illustrated in more details with reference to  FIGS. 5 and 6 .  FIG. 5  is a schematic cutaway view illustrating a rotary switch mechanism according to an embodiment of the present invention.  FIG. 6  is a schematic cutaway view illustrating the rotary switch mechanism of  FIG. 5  and taken along another viewpoint. The push button  36  comprises an optical finger navigation (OFN) module  362 , a push switch  363 , a push button holder  364 , an elastic element  365  and a push button circuit board  366 . The optical finger navigation module  362  is disposed within the push button  36  and arranged under the pushing surface  361  for detecting a motion of a user&#39;s finger F (see  FIG. 7 ) on the pushing surface  361 . In response to the motion of the user&#39;s finger F, the optical finger navigation module  362  generates a motion signal. The configurations and the operating principles of the optical finger navigation module  362  will be illustrated later. The push button holder  364  is disposed on a light guide structure  321  of the first rotatable member  32 . In addition, the push button holder  364  is movable upwardly and downwardly with respect to the first rotatable member  32 . The push button holder  364  comprises a central sleeve  3641  and a central hole  3642 . The central sleeve  3641  is disposed under the push switch  363 . The central hole  3642  is disposed in the center of the central sleeve  3641 . 
     The push button circuit board  366  is disposed on the push button holder  364 . In addition, the optical finger navigation module  362  is disposed on a first surface  3661  of the push button circuit board  366 . The push switch  363  is disposed on a second surface  3662  of the push button circuit board  366 . The elastic element  365  is sheathed around the central sleeve  3641  and sustained against a triggering part  323  of the first rotatable member  32  for providing an elastic force. Due to the elastic force, the push button holder  364  is movable upwardly to have the push button  36  restore to the original non-pressed position. In this embodiment, the elastic element  365  is a helical spring. 
     The first rotatable member  32  comprises the light guide structure  321 , plural perforations  322  and the triggering part  323 . The light guide structure  321  is disposed within the first rotatable member  32 . In addition, a top portion  3211  of the light guide structure  321  is exposed outside the first rotatable member  32  and arranged around the pushing surface  361  of the push button  36 . After the push button holder  364  is penetrated through the plural perforations  322 , the push button holder  364  is engaged with the light guide structure  321 . The triggering part  323  is arranged between the plural perforations  322 . In addition, the triggering part  323  is penetrated through the central hole  3642  and arranged in the vicinity of the push switch  363 . When the push button  32  is pressed down, the triggering part  323  is sustained against the push switch  363 , so that a triggering signal is generated by the push switch  363 . In this embodiment, the light guide structure  321  and the triggering part  323  are integrally formed. 
     Hereinafter, the internal configurations and the operating principles of the optical finger navigation module  362  will be illustrated with reference to  FIG. 7 .  FIG. 7  is a schematic cross-sectional view illustrating an optical finger navigation module of a rotary switch mechanism according to an embodiment of the present invention. As shown in  FIG. 7 , the optical finger navigation module  362  comprises a light source  3621 , a reflective mirror  3622 , a focusing lens  3623  and a motion sensor  3624 . The light source  3621  is used for emitting a light beam L. The light beam L is reflected by the reflective mirror  3622  and then projected on the pushing surface  361  of the push button  36 . In such way, when the user&#39;s finger F is in contact with the pushing surface  361  of the push button  36 , the light beam L can be projected on the user&#39;s finger F. After the light beam L is reflected by user&#39;s finger F, the light beam L is focused by the focusing lens  3623 . After the reflected and focused light beam L is received by the motion sensor  3624 , the motion sensor  3624  generates a motion signal. 
     Please refer to  FIGS. 5 and 6  again. In addition to the main circuit board  30 , the base  31 , the first rotatable member  32 , the second rotatable member  34  and the push button  36 , the rotary switch mechanism  3  further comprises a first signal-generating module  33 , a second signal-generating module  35  and plural light emitting diodes  37 . The plural light emitting diodes  37  are mounted on the main circuit board  30  for emitting plural light beams L*. After the plural light beams L* are directed to the light guide structure  321 , the light beams L* are guided by the light guide structure  321  and projected onto the region between the push button  36  and the first rotatable member  32 , thereby illuminating the first rotatable member  32 . The second signal-generating module  35  is mounted on the main circuit board  30 . In response to rotation of the second rotatable member  34 , the second signal-generating module  35  generates a second rotation signal. In this embodiment, the second signal-generating module  35  comprises an idle wheel  351  and an encoder  352 . The idle wheel  351  is disposed on the base  31 . In addition, the idle wheel  351  comprises a rotating shaft  3511  and plural idle wheel saw-toothed parts  3512 . The rotating shaft  3511  is extended from a middle portion of the idle wheel  351 . The plural idle wheel saw-toothed parts  3512  are arranged around the idle wheel  351 . In addition, the plural idle wheel saw-toothed parts  3512  are engaged with corresponding rotatable member saw-toothed parts  342  of the second rotatable member  34  (see  FIG. 8 ), so that the idle wheel  351  is synchronously rotated with the second rotatable member  34 . The encoder  352  is mounted on the main circuit board  30 . In addition, the rotating shaft  3511  of the idle wheel  351  is inserted into the internal portion of the encoder  352 . In response to rotation of the idle wheel  351 , the second rotation signal is generated by the encoder  352 . 
     The first signal-generating module  33  is mounted on the main circuit board  30 . In response to rotation of the first rotatable member  32 , the first signal-generating module  33  generates a first rotation signal. The first signal-generating module  33  comprises a magnetic ring  331  and a reed sensor assembly  332 . The magnetic ring  331  is disposed on a lower portion  324  of the first rotatable member  32 , so that the magnetic ring  331  is synchronously rotated with the first rotatable member  32 . The reed sensor assembly  332  is mounted on the main circuit board  30 , and arranged in the vicinity of the magnetic ring  331 . By detecting the rotation of the magnetic ring  331 , the reed sensor assembly  332  generates the first rotation signal. 
     Hereinafter, the configurations of the first signal-generating module  33  will be illustrated in more details with reference to  FIG. 9 .  FIG. 9  is a schematic top view illustrating the magnetic ring and the reed sensor assembly of the rotary switch mechanism according to an embodiment of the present invention. After a magnetizing operation is performed on the magnetic ring  331 , the magnetic ring  331  comprises plural N-pole regions  3311 , plural S-pole regions  3312  and plural spacer regions  3313 . One side of each spacer region  3313  is adjacent to an N-pole region  3311 . The other side of each spacer region  3313  is adjacent to an S-pole region  3312 . The reed sensor assembly  332  comprises a first reed sensor  3321  and a second reed sensor  3322 . In this embodiment, the first reed sensor  3321  is disposed under the N-pole region  3311  to detect the magnetic field change between the N-pole region  3311  and the S-pole region  3312 . The second reed sensor  3322  is disposed under the spacer region  3313  to detect the magnetic field change between the N-pole region  3311  and the S-pole region  3312 . That is, in response to the magnetic field change detected by the first reed sensor  3321  and the second reed sensor  3322 , the first rotation signal is generated. 
     In a case that the magnetic ring  331  is rotated in a first rotation direction C 1  (e.g. the clockwise direction), the magnetic field change from an N-pole region  3311  to an S-pole region  3312  is detected by the first reed sensor  3321 . When the rotation of the magnetic ring  331  is stopped, another S-pole region  3312  is disposed over the first reed sensor  3321 . At the same time, the magnetic field change from a non-magnetic spacer region  3313  to an N-pole region  3311  is detected by the second reed sensor  3322 . When the rotation of the magnetic ring  331  is stopped, another spacer region  3313  is disposed over the second reed sensor  3322 . In a case that the magnetic ring  331  is rotated in a second rotation direction C 2  (e.g. the anti-clockwise direction), the magnetic field change from an N-pole region  3311  to an S-pole region  3312  is detected by the first reed sensor  3321 . When the rotation of the magnetic ring  331  is stopped, another S-pole region  3312  is disposed over the first reed sensor  3321 . At the same time, the magnetic field change from a non-magnetic spacer region  3313  to an N-pole region  3311  is detected by the second reed sensor  3322 . When the rotation of the magnetic ring  331  is stopped, another spacer region  3313  is disposed over the second reed sensor  3322 . That is, by simulating the operations of the encoder, the reed sensor assembly  332  can judge the operating situation of the magnetic ring  331  and generate the first rotation signal. 
     Hereinafter, the operations of the rotary switch mechanism  3  will be illustrated with reference to  FIGS. 5 and 6 . When the push button  36  of the rotary switch mechanism  3  is pressed down, in response to the downward force, the push button holder  364  is moved downwardly to compress the elastic element  365 . As the push button holder  364  is moved downwardly, the push switch  363  on the push button holder  364  and the triggering part  323  that is penetrated through the central hole  3642  will be contacted with each other. Under this circumstance, the push switch  363  is triggered to generate a pushing signal. According to the pushing signal, the computer system (not shown) connected with the rotary switch mechanism  3  will execute a pushing command. Whereas, when the push button  36  is no longer pressed down and the downward force exerted on the push button  36  is eliminated, the compressed elastic element  365  is restored to generate an elastic force. Due to the elastic force exerted on the push button holder  364 , the push button holder  364  is returned to the original non-pressed position. 
     Please refer to  FIGS. 4 and 8  again. When the user&#39;s finger F is moved on the optical finger navigation module  362  of the push button  36 , the light beam L emitted by light source  3621  of the optical finger navigation module  362  is projected on the pushing surface  361  of the push button  36  and reflected by the user&#39;s finger F. Then, the light beam L is focused by the focusing lens  3623  and received by the motion sensor  3624 , so that a motion signal is generated by the motion sensor  3624 . According to the motion signal, the computer system (not shown) connected with the rotary switch mechanism  3  will execute a moving command. By executing the moving command, the cursor shown on the computer system is correspondingly moved. Under this circumstance, the rotary switch mechanism  3  has a function similar to a mouse device. 
     Please refer to  FIGS. 5 and 6  again. In a case that the first rotatable member  32  of the rotary switch mechanism  3  is rotated, the magnetic ring  331  is synchronously rotated with the first rotatable member  32 . In addition, by detecting the magnetic field change according to the rotation of the magnetic ring  331 , the reed sensor assembly  332  generates the first rotation signal. According to the first rotation signal, the computer system (not shown) connected with the rotary switch mechanism  3  will execute a first rotation command. 
     In a case that the second rotatable member  34  of the rotary switch mechanism  3  is rotated, since the rotatable member saw-toothed parts  342  of the second rotatable member  34  are engaged with the plural idle wheel saw-toothed parts  3512  of the idle wheel  351 , the idle wheel  351  is driven to rotate by the second rotatable member  34 . Moreover, since the rotating shaft  3511  of the idle wheel  351  is inserted into the encoder  352 , in response to rotation of the idle wheel  351 , the encoder  352  generates the second rotation signal. According to the second rotation signal, the computer system (not shown) connected with the rotary switch mechanism  3  will execute a second rotation command. 
     From the above description, the rotary switch mechanism of the present invention comprises a first rotatable member and a second rotatable member. In addition, the second rotatable member is arranged around the first rotatable member, so that the first rotatable member and the second rotatable member are collectively defined as a two-layered rotary switch structure. In other words, the rotary switch mechanism of the present invention can be used to execute two rotation commands, thereby performing two rotary switch functions. In addition, the first rotatable member of the rotary switch mechanism comprises an optical finger navigation module and a push switch. By means of the optical finger navigation module and the push switch, the cursor-moving command and the clicking and selecting command are executed. In other words, by the first rotatable member, the second rotatable member, the optical finger navigation module and the push switch, the rotary switch mechanism of the present invention can be used to execute four commands. Since the configurations and functions of these four components are independent of each other, any two of these components may be operated to execute another different command. For example, the sound volume adjustment command (i.e. the first rotation command) is executed by rotating the first rotatable member; the text file proportional scale command (i.e. the second rotation command) is executed by rotating the second rotatable member; the cursor-moving command (i.e. the motion command) is executed by moving the user&#39;s finger on the optical finger navigation module; and the clicking and selecting command is executed by pressing the push switch. Whereas, by simultaneously rotating the first rotatable member and moving the user&#39;s finger on the optical finger navigation module, the original sound volume adjustment command and the original cursor-moving command are not executed, but the image file proportional scale command (i.e. another command) is executed. From the above description, any two of the four components (i.e. the first rotatable member, the second rotatable member, the optical finger navigation module and the push switch) may be operated to execute an additional command. In other words, the rotary switch mechanism of the present invention may be used for executing more commands when compared with the prior art. 
     Moreover, since the configurations and functions of the four components are independent of each other, the rotary switch mechanism of the present invention is easily operated and the possibility of causing erroneous operation is minimized. 
     While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.