Patent Publication Number: US-7211755-B1

Title: Knob structure

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This non-provisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No(s). 094222562 filed in Taiwan, R.O.C. on Dec. 23, 2005, the entire contents of which are hereby incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   The present invention relates to a knob structure, and particularly to a knob structure applied in an electronic device, wherein a preset control signal is input by rotating the knob structure. 
   2. Related Art 
   With the rapid popularity of multimedia technologies and applications, more and more types of portable electronic devices are appearing, such as mobile telephones, personal digital assistants (PDA), digital cameras, MP3 players, MPEG4 players, recording digital photo frames, and handheld game players. Further, with continuous advancement of science and technology, those portable electronic devices are becoming smaller in volume to be carried more conveniently by users and more powerful in function to satisfy their requirements. 
   Regarding the MP3 player which is quite popular at present, the MP3 player comprises a main part at least comprising a display screen and a plurality of keys, wherein the display screen is used to display a list of songs, and a series of actions, such as enter, play, forward, and backward, may be performed through the keys. A user may operate the MP3 player more conveniently if there are more keys, but the volume of the MP3 player will become larger. On the other hand, if the number of the keys is small, though the volume of the MP3 player may be reduced, many operations will need to be performed by pressing two or three keys simultaneously, which complicates operation for the user. 
   In order to solve the problem that volume and convenience of operation conflict with each other, an electronic touch knob is applied in an iPod player introduced by Apple Computer Inc. The user may rotate the touch knob to send a corresponding preset command, and by using a menu operation interface, the user may conveniently perform actions such as enter, play, forward, or backward conveniently. The user may also use the touch knob to adjust sound volume. Through the design of the touch knob, the iPod can not only perform various functions easily, but also has a reasonably small volume. Through the design of the touch knob of the iPod, the user may rotate and slide the knob in a corresponding region in the body by a finger, which lacks the touch feeling the user may have when pressing the keys. In order to show response to the action of the user, a buzzer is added into the electrical part of the iPod and displayed through the display screen. 
   Similarly, in order to solve the problem that the convenience of operation and the volume conflict with each other, besides that the iPod employs the electronic touch knob, a mechanical knob structure may be disposed in the MP3 player. For example, a rotary component has been disclosed in Japan Patent No. 2000297077. The rotary component comprises a cabinet and a rotary body, wherein the rotary body may rotate on the cabinet and output a control signal. Referring to  FIG. 1 , it is a schematic view of a rotary component  41  applied in a MP3 player  53 . A rotary wheel  42  is fixedly combined with the rotary component  41 , and a through-hole  531  is perforated in the body case of the MP3 player  53  corresponding to the position of the rotary wheel  42 . After the rotary component  41  and the rotary wheel  42  are installed on a circuit board  532  of the MP3 player  53 , the through-hole of the body case is covered corresponding to the rotary wheel  42 . Since a flange is disposed between the cabinet of the rotary component  41  and the rotary body, the user will feel fragmental tactility through the flange when operating the rotary wheel  42  to drive the rotary body to rotate. As such, the user may know whether the operation is performed through the physical tactility, so the buzzer demanded by the electronic touch knob is unnecessary. 
   For the MP3 player adopting the rotary component, during the practical production and assembly, the rotary component and the rotary wheel are firstly assembled on the circuit board and locked with the body case together. Among the rotary component, the rotary wheel, the through-hole in the body case, and the body itself has dimensional errors, and the dimensional errors are summed up when the components are assembled. The rotary wheel and the through-hole of the body will interfere with each other easily due to dimensional errors. As such, the user may feel it is inconvenient to operate due to the interference, and if the interference is serious, the MP3 player will be determined to be scraped. 
   Furthermore, the aforementioned rotary wheel does not have the function of light indication, so it is difficult for the user to operate when light is insufficient or at night. Further, at present, keys of a mobile phone are provided with a backlight source and when the user presses a press key, the backlight source is triggered to illuminate the position of the press key, such that the user can use the mobile phone conveniently. However, for the aforementioned rotary wheel, the luminescent design cannot be adopted due to the aforementioned interference. 
   SUMMARY OF THE INVENTION 
   According to one aspect of the invention, a knob structure is provided on an electronic device. The knob structure may comprise a rotary encoder, a plurality of light emitting sources, a light guiding ring, a brake wheel, and a rotary wheel. 
   Accordingly, it is an object of the invention to provide a knob structure in which the rotary wheel may smoothly rotate on the body case in a manner of non-fixed engagement to reduce the number of defective products and alleviate the problem of the interference, so as to greatly enhance the product yield and reduce the production cost. 
   Another object of the invention is to provide a knob structure which may provide the bright lights generated by the light emitting sources in an environment with insufficient lights or at night to indicate the position of the knob. 
   Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the present invention, and wherein: 
       FIG. 1  is a schematic view of a conventional knob structure applied in an electronic device; 
       FIG. 2  is an exploded schematic view of the structure of one embodiment of the present invention; 
       FIG. 3  is another exploded schematic view of the structure of the present invention; 
       FIGS. 4A and 4B  are sectional schematic views of a partial structure of the present invention; 
       FIGS. 5A ,  5 B, and  5 C are sectional schematic views of a partial structure of the present invention; 
       FIG. 5A  is an exploded schematic view when the present invention is applied in an electronic device; 
       FIG. 5B  is a assembly schematic view when the present invention is applied in an electronic device; 
       FIG. 6  is a assembly schematic view of the present invention; and 
       FIGS. 7A and 7B  are schematic views of a second embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The knob structure disclosed by the present invention is disposed on an electronic device and used to input a preset control signal. The so-called control signal refers to the signal input into the electronic device to perform an action, such as enter, play, forward, backward, and sound volume control, according to a pulse signal generated by the knob structure, wherein the electronic device refers to an electronic data processing device, such as a mobile telephone, a PDA, a digital camera, a MP3 player, a MPEG4 player, a recording digital photo frame, and a handheld game player. In the following detailed illustration about the present invention, a knob structure applied in a MP3 player will be illustrated as one preferred embodiment of the present invention. 
   Referring to  FIG. 2 , a light emitting knob structure of the present invention is applied in an electronic device  20 , wherein the electronic device  20  is a MP3 player. The electronic device  20  at least comprises a body case  21  and a circuit board  22  with a plurality of electronic parts, wherein at least one round hole  211  is formed in the body case  21 . 
   Referring to  FIG. 3 , the knob structure disclosed by the present invention comprises a rotary encoder  11 , a plurality of light emitting sources  14 , a light guiding ring  15 , a brake wheel  12 , and a rotary wheel  13 . The rotary encoder  11  at least comprises a fixing base  111  and a rotary ring  112 , wherein the rotary ring  112  rotates on the fixing base  111  and generates a pulse signal, and the rotary ring  112  rotates in a stepped manner on the fixing base  111 , so as to generate fragmental tactility when the user controls the rotation. The specific structural composition of the rotary encoder  11  and the operating principle have been described in Japan Patent No. 2000297077 and will not be described any more here. A plurality of locking slots  1121  is disposed in the rotary ring  112 . 
   The plurality of light emitting sources  14  is light emitting diodes (LEDs) or other similar light emitting components. The light emitting sources  14  are disposed on the circuit board  22  and arranged around the circumference of the rotary encoder  11 , wherein lights are generated when the light emitting sources are powered on. 
   The light guiding ring  15  has the shape of a ring, the inner diameter of which is larger than the outer diameter of the rotary encoder  11 . A plurality of grooves  151  corresponding to the light emitting sources  14  are disposed on the bottom of the light guiding ring  15 , such that the light guiding ring  15  can be just disposed on the outer edge of the rotary encoder  11  and covered on the light emitting sources  14 . The material of the light guiding ring  15  is a light transmissive material capable of diffusing lights. The centralized lights emitted by the light emitting sources  14  are diffused to be uniformized after entering the light guiding ring  15 . 
   The brake wheel  12  is a ringed formation made of a light transmissive material, the inner diameter of which is about equal to that of the rotary ring  112 . A plurality of wedges  121  corresponding to the locking slots  1121  is disposed on the brake wheel  12 . As shown in  FIG. 3 , through embedding the wedges  121  into the locking slots  1121 , the brake wheel  12  is fixedly combined with rotary ring  112 , so as to drive the rotary ring  112  to rotate on the fixing base  111 . Additionally, a plurality of ratchets  122  is disposed around the circumference of the brake wheel  12 . 
   The rotary wheel  13  is a ringed formation made of a transmissive material and comprises a stop ring  131  larger than the outer diameter of the ringed formation. The rotary wheel  13  is separated into an upper part  133  and a lower part  132  by the stop ring  131 , wherein the inner diameter of the lower part  132  is slightly greater than the maximum outer diameter (including the height of the ratchet  122 ) of the brake wheel  12 . A block  135  that extends inwards is disposed on the inner edge of the lower part  132 , wherein the length of the block  135  is slightly smaller than the height of the ratchet  122 . Additionally, anti-slip stripes  1321  are formed on the top surface of the upper part  133 . 
   As shown in  FIGS. 4A and 4B , firstly, the light guiding ring  15  is disposed on the outer edge of the rotary encoder  11  and covered on the light emitting sources  14 . As shown in  FIGS. 5A ,  5 B, and  5 C, the brake wheel  12  is embedded into the locking slot  1121  via the wedge  121 , so as to fixedly combine with the rotary ring  112 . The rotary wheel  13  is nested on the brake wheel  12 , and the block  135  is embedded between any two corresponding ratchets  122  of the brake wheel  12 , so the rotary wheel  13  is engaged with the brake wheel  12  non-fixedly. When the rotary wheel  13  is controlled to rotate, the brake wheel  12  drives the rotary ring  112  to rotate, such that the rotary encoder  11  generates a preset control signal. The length difference between the block  135  and the ratchet  122  defines the movement margin of the rotary wheel  13  on the brake wheel  12 . 
   Further as shown in  FIGS. 2 and 6 , the brake wheel  12  is fixedly combined with the rotary ring  112  of the rotary encoder  11 , as shown in  FIG. 3 . Then, the rotary wheel  13  is nested on the brake wheel  12  non-fixedly, with the block  135  of the rotary wheel  13  embedded between any two corresponding ratchets  122  of the brake wheel  12 . After that, the round hole  211  of the body case  21  is covered on the circuit board  22  corresponding to the rotary wheel  13 , with the stop ring  131  of the rotary wheel  13  against the inner wall of the corresponding round hole  211  of the body case  21 . Since the length difference between the block  135  and the ratchet  122  defines the movement margin of the rotary wheel  13  on the brake wheel  12 , the round hole  211  of the body case  21  can still smoothly enclose the rotary wheel  13  as long as the assembly error between the body case  21  and the rotary wheel  13  falls within the movement margin. The upper part  133  of the rotary wheel  13  slightly projects from the body case  21 , such that the user may press the upper part  133  of the rotary wheel  13  through a finger to control the rotation of the rotary wheel  13  and make the rotary encoder  11  generate the preset control signal when the brake wheel  12  and the rotary ring  112  are driven to rotate. 
   Through the design of the antis-lip stripes  1321  on the upper part  133  of the rotary wheel  13 , the user still may control and rotate the rotary wheel  13  conveniently through a finger. Since the rotary wheel  13  and the brake wheel  12  are engaged non-fixedly, the assembly errors between the rotary encoder  11 , the rotary wheel  13 , and the body case  21  may be aligned through the movement margin between the ratchets  122  and the block  135 , such that the rotary wheel  13  may rotate smoothly on the body case  21 . Furthermore, lights from the light emitting sources  14  are emitted outwards after passing through the light guiding ring  15 , the brake wheel  12 , and the rotary wheel  13 , thereby illuminating the rotary wheel  13 . 
   A cover  16  is disposed on the center of the rotary wheel  13  and a switch (not shown) is disposed in a corresponding position of the cover  16 , such that the cover  16  is used as a button. 
   As shown in  FIGS. 7A and 7B , it is a schematic view of a second embodiment of the present invention, wherein a tray  30  corresponding to the round hole  211  is provided. A hole  31 , the inner diameter of which is slightly smaller than the outer diameter of the lower part  132  of the rotary wheel  13 , is formed in the tray  30 . The rotary wheel  13  may be firstly nested on the round hole  211  of the body case  21 , and then the tray  30  is fixedly combined with the bottom of the body case  21  corresponding to the rotary wheel  13 , such that the rotary wheel  13  is rotatably nested on the hole  31 . Similarly, the brake wheel  12  is fixedly combined with the rotary ring  112  of the rotary encoder  11 . When the body case  21  and the rotary wheel  13  are covered on the circuit board  22  together corresponding to the rotary encoder  11 , the block  135  of the rotary wheel  13  is embedded into any two corresponding ratchets  122 , such that the rotary wheel  13  and the brake wheel  12  are engaged non-fixedly. As such, the assembly errors between the rotary encoder  11 , the rotary wheel  13 , and the body case  21  are aligned through the movement margin between the ratchets  122  and the block  135 , such that the rotary wheel  13  can smoothly rotate on the body case  21 . 
   The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.