Abstract:
An active stylus without function keys is disclosed to include a pen body defining therein an accommodation chamber, a control device mounted inside the accommodation chamber and including a circuit board capable of outputting a signal to a touch control device of a touch screen being touched by the active stylus and two first conductors electrically connected to the circuit board, and a rotating barrel rotatably mounted on the pen body around the control device, the rotating barrel including a second conductor movable with the rotating barrel relative to the pen body into contact with either or both of the two first conductors or away from the first conductors to provide one of a series of signals for driving circuit board to output a corresponding control signal to the touch control device of the touch screen.

Description:
This reference is based on Provisional Application Ser. No. 61/928,881, filed on Jan. 17, 2014, currently pending. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a touch-sensing input device and more particularly, to an active stylus with switching functions, which uses a rotating barrel to switch a control device instead of the use of function keys, preventing from inadvertently touching function keys and improving the convenience of the operation of the active stylus. 
     2. Description of the Related Art 
     With fast development of modern technology, various advanced electronic products such as smart phone, touchscreen computers and TVs that have the characteristic of ease of use have been created and appeared on the market. Instead of the use of a keyboard or keypad in a computer or mobile phone for data input, a smart phone, tablet computer, touch screen computer or touch screen TV allows a user to operate it by touching or approaching a software icon on the surface of its touch screen directly with the finger or a stylus. 
     A stylus may be equipped with multiple function keys for switching by the user to initiate different functional operations, such as color change, clear, switching windows or screenshot, eliminating a complicated clicking procedure and saving much operating time. 
     However, in order to mate with different versatile designs of advanced electronic products, the number of stylus function keys must be relatively increased. When using a stylus, the user can inadvertently touch the function keys to initiate an undesired functional operation. 
     Therefore, it is desirable to provide a stylus with switching functions that eliminates the aforesaid problem. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide an active stylus with switching functions, which uses a rotating barrel to switch a control device instead of the use of function keys, preventing from inadvertently touching function keys and improving the convenience of the operation of the active stylus. 
     To achieve this and other objects of the present invention, an active stylus includes a pen body defining therein an accommodation chamber; a control device mounted inside the accommodation chamber, including a circuit board capable of outputting a signal to a touch control device of a touch screen being touched by the active stylus and two first conductors electrically connected to the circuit board; and a rotating barrel rotatably mounted on the pen body around the control device, including a second conductor movable with the rotating barrel relative to the pen body into contact with either or both of the two first conductors, or away from the first conductors, to provide one of a series of signals for driving circuit board to output a corresponding control signal to the touch control device of the touch screen. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique top elevational view of an active stylus in accordance with the present invention. 
         FIG. 2  is an oblique top elevational view of the present invention after removal of the upper pen holder from the pen body. 
         FIG. 3  is a cross-sectional view of the present invention, illustrating the relationship between the control device and the rotating barrel. 
         FIG. 4  is an oblique top elevational view of the present invention after removal of the upper pen holder from the pen body when viewed from the bottom side. 
         FIG. 5  is an oblique top elevational view of the present invention after removal of the upper pen holder and lower pen holder from the active stylus. 
         FIG. 6  is a perspective view of the rotating barrel in accordance with the present invention. 
         FIG. 7  is a perspective view of the inner metal barrel member of the rotating barrel in accordance with the present invention. 
         FIG. 8A  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the first operating position (I). 
         FIG. 8B  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the first operating position (II). 
         FIG. 8C  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the first operating position (III). 
         FIG. 9  is an equivalent circuit diagram of the control device and rotating barrel of the active stylus in accordance with the present invention. 
         FIG. 10A  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the second operating position (I). 
         FIG. 10B  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the second operating position (I). 
         FIG. 10C  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the second operating position (I). 
         FIG. 11A  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the third operating position (I). 
         FIG. 11B  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the third operating position (I). 
         FIG. 11C  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the third operating position (I). 
         FIG. 12A  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fourth operating position (I). 
         FIG. 12B  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fourth operating position (I). 
         FIG. 12C  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fourth operating position (I). 
         FIG. 13A  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fifth operating position (I). 
         FIG. 13B  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fifth operating position (I). 
         FIG. 13C  is a schematic sectional view of the present invention, illustrating a status of the active stylus after the rotating barrel rotated to the fifth operating position (I). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1-7 , an active stylus with a switching function in accordance with the present invention is shown. As illustrated, the active stylus comprises a pen body  1 , a control device  2 , and a rotating barrel  3 . 
     As illustrated in  FIG. 1 , the pen body  1  comprises a lower pen holder  11  having a front touch head  111  at a front end thereof, an upper pen holder  12  located at an opposing top end of the lower pen holder  11 , and an accommodation chamber  10  defined within the lower pen holder  11  and the upper pen holder  12 . 
     As illustrated in  FIGS. 2, 3 and 4 , the control device  2  comprises a circuit board  21 , and a hollow semi-cylindrical insulator  22  located at a back side of the circuit board  21 . The circuit board  21  comprises two first conductors  211  bilaterally arranged at the back side thereof in a transversely spaced manner and respectively exposed out of the hollow semi-cylindrical insulator  22 , and a conductive shrapnel  212  located at a rear side relative to the first conductors  211  and grounded. The hollow semi-cylindrical insulator  22  comprises a through hole  221  that receives a part of the conductive shrapnel  212 , and a positioning rib  222  located at a rear side relative to the through hole  221 . 
     As illustrated in  FIGS. 5 and 6 , the rotating barrel  3  comprises an outer insulative barrel member  31 , and an inner metal barrel member  32  located in the outer insulative barrel member  31 . As illustrated in  FIG. 7 , the inner metal barrel member  32  comprises a semicircular second conductor  321  forwardly extended from a lower part of a circular front edge thereof, a front locating slot  322  longitudinally cut through an opposing upper part of the peripheral wall thereof and equally spaced between two opposite lateral sides of the semicircular second conductor  321 , and a plurality of rear positioning slots  323  longitudinally cut through the peripheral wall thereof and extending to an opposing circular rear edge thereof. 
     In installation, mount the control device  2  in the accommodation chamber  10  of the pen body  1 , and sleeve the rotating barrel  3  onto the pen body  1  to attach the inner metal barrel member  32  to the periphery of the hollow semi-cylindrical insulator  22  of the control device  2 . Thus, the pen body  1 , the control device  2  and the rotating barrel  3  are assembled, constituting the active stylus. 
     It is to be understood that installing the control device  2  in the accommodation chamber of the pen body  1  is simply an example of the invention, but not intended to limit the scope of the invention. Alternatively, the control device  2  can be installed in the lower pen holder  11 , the upper pen holder  12 , or any other part of the pen body  1 . 
     Further, the hollow semi-cylindrical shape of the insulator  22  of the control device  2  is simply an example of the invention, but not intended to limit the scope of the invention. Polygonal shape or any other irregular shape can be selected as an alternation. Further, the inner metal barrel member  32  of the rotating barrel  3  can be directly attached to the first conductors  211 , eliminating the use of the hollow semi-cylindrical insulator  22  without departing from the spirit and scope of the invention. 
     Referring to  FIG. 9  and  FIGS. 4 and 6  again, the circuit board  21  comprises a voltage source V DD , a plurality of resistors R 1 ;R 2  corresponding to the first conductors  211 , and a control unit  213 . The voltage source V DD  is electrically connected to respective one ends of the resistors R 1 ;R 2 . The opposite ends of the resistors R 1 ;R 2  are respectively electrically connected to the first conductors  211  that are then electrically coupled to the control unit  213 . The left-sided first conductor  211  is adapted for contacting the semicircular second conductor  321  to switch on a first switch SW 1 . The right-sided first conductor  211  is adapted for contacting the semicircular second conductor  321  to switch on a second switch SW 2 . 
     Referring to  FIGS. 8A, 8B and 8C , the invention is applicable to a capacitive stylus as well as a resistive stylus. In actual application, attach the front touch head  111  of the lower pen holder  11  to the surface of the touch screen, and then rotate the rotating barrel  3  to a first operating position to have the positioning rib  222  of the hollow semi-cylindrical insulator  22  of the control device  2  be positioned in one rear positioning slot  323  of the rotating barrel  3  (see  FIG. 8C ). At this time, the inner metal barrel member  32  is attached to the conductive shrapnel  212  that is grounded (see  FIG. 8B ), and therefore the circuit of the circuit board  21  forms an operating loop to turn on the power supply. Further, the semicircular second conductor  321  of the inner metal barrel member  32  simultaneously touches the two first conductors  211  (see  FIG. 8A ), therefore, the first switch SW 1  and the second switch SW 2  are electrically conducted (closed circuit), enabling the voltage source V DD  to provide a first signal combination (0,0) through the resistors R 1 ;R 2  to the control unit  213 . At this time, the control unit  213  provides a first signal to the touch control device, enabling the front touch head  111  of the lower pen holder  11  to operate the touch screen in executing the function of, for example, color change, clear, switching windows, or screenshot. 
     Referring to  FIGS. 10A, 10B and 10C , when rotating the rotating barrel  3  in the clockwise direction through 90° to a second operating position to have the positioning rib  222  of the hollow semi-cylindrical insulator  22  of the control device  2  be positioned in another rear positioning slot  323  of the rotating barrel  3  (see  FIG. 10C ). At this time, the inner metal barrel member  32  is attached to the conductive shrapnel  212  that is grounded (see  FIG. 10B ), and therefore the circuit of the circuit board  21  forms an operating loop to turn on the power supply. Further, the semicircular second conductor  321  of the inner metal barrel member  32  simply touches the right-sided first conductor  211  (see  FIG. 10A ), therefore, the first switch SW 1  is electrically disconducted (open circuit) and the second switch SW 2  is electrically conducted (closed circuit), enabling the voltage source V DD  to provide a second signal combination (1,0) through the resistors R 1 ;R 2  to the control unit  213 . At this time, the control unit  213  provides a second signal to the touch control device, enabling the front touch head  111  of the lower pen holder  11  to operate a touch control on the touch screen. 
     Referring to  FIGS. 11A, 11B and 11C , when rotating the rotating barrel  3  in the counter-clockwise direction through 75° from the first position to a third operating position to have the positioning rib  222  of the hollow semi-cylindrical insulator  22  of the control device  2  be positioned in another rear positioning slot  323  of the rotating barrel  3  (see  FIG. 11C ). At this time, the inner metal barrel member  32  is attached to the conductive shrapnel  212  that is grounded (see  FIG. 11B ), and therefore the circuit of the circuit board  21  forms an operating loop to turn on the power supply. Further, the semicircular second conductor  321  of the inner metal barrel member  32  is kept away from the first conductors  211  (see  FIG. 11A ), therefore, the first switch SW 1  and the second switch SW 2  are electrically disconducted (open circuit), enabling the voltage source V DD  to provide a third signal combination (1,1) through the resistors R 1 ;R 2  to the control unit  213 . At this time, the control unit  213  provides a third signal to the touch control device, enabling the front touch head  111  of the lower pen holder  11  to operate a touch control on the touch screen. 
     Referring to  FIGS. 12A, 12B and 12C , when rotating the rotating barrel  3  in the clockwise direction through 15° from the third position to a fourth operating position to have the positioning rib  222  of the hollow semi-cylindrical insulator  22  of the control device  2  be positioned in another rear positioning slot  323  of the rotating barrel  3  (see  FIG. 12C ). At this time, the conductive shrapnel  212  of the circuit board  21  is positioned in the front locating slot  322  of the inner metal barrel member  32  without contacting the inner metal barrel member  32  (see  FIG. 12B ), and therefore the circuit of the circuit board  21  is off. 
     Referring to  FIGS. 13A, 13B and 13C , when rotating the rotating barrel  3  in the counter-clockwise direction through 105° from the first position to a fifth operating position to have the positioning rib  222  of the hollow semi-cylindrical insulator  22  of the control device  2  be positioned in another rear positioning slot  323  of the rotating barrel  3  (see  FIG. 13C ). At this time, the inner metal barrel member  32  is attached to the conductive shrapnel  212  that is grounded (see  FIG. 13B ), and therefore the circuit of the circuit board  21  forms an operating loop to turn on the power supply. Further, the semicircular second conductor  321  of the inner metal barrel member  32  simply touches the left-sided the first conductor  211  (see  FIG. 13A ), therefore, the first switch SW 1  is electrically conducted (close circuit) and the second switch SW 2  is electrically disconducted (open circuit), enabling the voltage source V DD  to provide a fourth signal combination (0,1) through the resistors R 1 ;R 2  to the control unit  213 . At this time, the control unit  213  provides a fourth signal to the touch control device, enabling the front touch head  111  of the lower pen holder  11  to operate a touch control on the touch screen. 
     In the above-described embodiment, the rotating angles of the rotating barrel  3  are simply examples of the invention, but not intended to limit the scope of the invention. In actual application, the arrangement of the control device  2  and the internal components inside the rotating barrel  3  can be relatively changed subject to the size of the active stylus or its touch control functions so as to further alter the rotating angles of the rotating barrel  3  relative to the control device  2 . 
     Further, the arrangement of the two transversely aligned first conductors  211  is simply example of the invention, but not intended to limit the scope of the invention. Alternatively, the control device  2  can be made having simply one first conductor  211 , or more than two first conductors  211 ; the rotating barrel  3  can be made having multiple second conductors  321  to work with the at least one first conductor  211  of the control device  2  in generating one of a series of signals to the control unit  213  for a different functional control. 
     By rotating the rotating barrel  3  relative to the control device  2  to move the second conductor  321  into contact with either or all of the first conductors  211 , or not into contact with any first conductor  211 , one of a series of input signals is provided to the control unit  213 , enabling the control unit  213  to provide a specific control signal to the touch control device to switch between different touch-control operating functions. This design eliminates the arrangement of any function keys, preventing from inadvertently touching function keys and improving the convenience of the operation of the active stylus. 
     In conclusion, the active stylus of the present invention is characterized in that rotating the rotating barrel  3  to move the second conductor  321  into contact with either or all of the first conductors  211 , or not into contact with any first conductors  211 , can drive the circuit board  21  to output one of a series of signals to the touch control device, switching the functional operation of the active stylus on the touch screen. 
     Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.