Patent Publication Number: US-2013234846-A1

Title: Antenna Mounting Structure for a Monitoring Component of an Onboard Power-Taking Port

Description:
FIELD OF THE INVENTION 
     The present invention relates to an onboard equipment connective construction and more particularly, relates to an antenna mounting structure for a monitoring component of an onboard power-taking port. 
     BACKGROUND OF THE INVENTION 
     Minimization of onboard equipment has direct influence on commercial promotion of the product. A tire pressure monitoring unit, which is small-sized, easy to be connected, has various functions, and is equipped with a display, will of course bring more successful commercial value, compared to another product which uses a large sized display and occupies large space. 
     Reference is made to Chinese Patent Application No. 101474973 disclosing an onboard equipment connective structure and an onboard display which partially fulfilled the above purposes. The improvement of it lies in external devices such as display are integrated by using a specific connective structure into a power-taking construction connected with a power-taking port located inside the cab. As such, these devices such as display can obtain electric power directly from the power-taking port inside the cab and perform other control functions, thereby realizing the same object without causing damage to cable connection layout. 
     A car power-taking port is also referred as to a car cigar lighter. The car cigar lighter defines internally a cylindrical room at the bottom of which a first connective electrode is disposed and at a cylindrical wall of which a second connective electrode of a power supply is disposed. A power-taking device is inserted into the cylindrical room and power-taking is performed by connecting of the device with both the first and second connective electrodes. 
     The dimension of a power-taking port is specified by industry standard. Accordingly, conventional idea is to make the power-taking device itself perform power obtaining function. For example, as illustrated in Chinese Patent Application No. CN101474973, the entire internal and external space occupied by the power-taking device are intended only for obtaining electric power, and no other function can be realized. As a result, external devices such as display and control circuits for these devices must be positioned on the outside of the power-taking device. Consequently, the whole product can&#39;t be reduced in size completely. 
     It is critical to know how to minimize the size of the equipment, get rid of conventional idea, and reasonably utilize space. To reasonably utilize space, every component inside the equipment should be re-arranged more effectively. 
     For equipment with control function such as tire pressure monitoring unit which receives signal from a tire pressure gauge, transforms the signal into readable information and then output the same information, to guarantee reliability of signal receiving and transmitting, the antenna should be distributed reasonably. Higher requirement regarding hiding and arrangement of the antenna will be presented once the equipments are required to be further reduced in dimension. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to overcome the drawbacks of prior art technology and provide an antenna mounting structure for a monitoring component of an onboard power-taking port, thus ensuring that minimized monitoring component of the onboard power-taking port will be able to receive and transmit signal without mistakes. 
     To fulfill the above object, the present invention provides the following technical solution. 
     An antenna mounting structure for a monitoring component of an onboard power-taking port includes a power-taking component disposed inside a power-taking space of the port and engaged with the port so as to realize power taking, a control circuit powered by the power coming from the power-taking component, a carrier for carrying the control circuit, an antenna and a display unit both of which are electrically connected with the control circuit, and an enclosure member cooperative with the power-taking component so as to enclose the control circuit and display unit therein. The control circuit receives an external signal by the antenna and process the external signal so that the signal is provided to the display unit for displaying the same; a circular groove is defined in an external end of the power-taking component or defined in the enclosure member; and the antenna is placed into the circular groove. 
     Preferably, the circular groove has a threaded portion and correspondingly, the antenna also has a threaded portion. The circular groove is formed on an outer wall of the power-taking component or defined on an outer wall of the enclosure member. 
     Preferably, the enclosure member includes a lid assembled with the external end of the power-taking component; and the circular groove is formed in an outer or inner wall of the lid. 
     Preferably, the power-taking component includes an extension portion extending along the external end of the component; the extension portion is assembled with the enclosure member; and the circular groove is formed in an outer or inner wall of the extension. 
     Preferably, the power-taking component has a first receiving space into which the control circuit and carrier are disposed. 
     Furthermore, the enclosure member includes a protective cap for covering and enclosing the periphery of the display unit and permitting visible of a screen of the display unit. 
     In addition, the carrier and display unit are disposed at two opposite surfaces of a supporting disc respectively; and the supporting disc is secured in the first receiving space of the power-taking component at an axial location. 
     More preferably, the supporting disc is secured on a flange predefined on the inner wall of the power-taking component. 
     Specifically, the enclosure member and power-taking port are connected with each other by screw or snap-fitting. 
     Compared with prior art, the present invention has the following advantages. 
     Firstly, though the dimension of the monitoring component is further reduced, the antenna may still receive and transmit signals without any mistake and obstacle due to arrangement of the antenna and display unit into the external end of the power-taking component. Furthermore, the display unit is able to display related information intuitively to the passengers, thereby meeting requirement of monitoring. The generality of the present monitoring component is also improved due to reliable signal transmission and receiving of the antenna and accordingly, the monitoring component may find its application in other fields where communication among electronic devices is needed, including but not limited to the tire pressure monitoring system. 
     Secondly, the control circuit and its carrier are integrated into the first receiving space of the power-taking component. In addition, the antenna and display unit are located at the external end of the power-taking component. As such, the first receiving space is used more effectively, and the entire monitoring component is further reduced in size. For example, the length of the component is basically limited to be no larger than 1.5 times of the length of the power-taking port. Alternatively, the length of the component may be further limited to be the length of the port. As the size is significantly reduced, the monitoring component of the invention becomes more convenient for carrying, more easy to mount and therefore, more favorable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a perspective view of a monitoring component of an onboard power-taking port according to a preferred embodiment of the present invention; 
         FIG. 2  shows a perspective exploded view of the monitoring component of the onboard power-taking port according to a preferred embodiment of the present invention; 
         FIG. 3  shows a cross-sectional view of the monitoring component of the onboard power-taking port according to a preferred embodiment of the present invention; 
         FIG. 4  shows an exploded perspective view of a first power-taking electrode of the monitoring component of the onboard power-taking port according to a preferred embodiment of the present invention; and 
         FIG. 5  shows a cross-sectional view of the monitoring component of the onboard power-taking port according to a preferred embodiment of the present invention, wherein top portion thereof has been removed to show internal construction of a power-taking component. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The various embodiments of the invention will be described in detail in conjunction with the accompanying drawings. 
     Reference is made to  FIGS. 1 and 2 . It is noted that the antenna mounting structure for a monitoring component of an onboard power-taking port of the present invention is implemented based on the monitoring component of the onboard power-taking port. In a preferred embodiment of the invention, the monitoring component of the onboard power-taking port includes a power-taking component  4 , a carrier  32 , a control circuit  6 , an antenna  5  and a display unit  31 . 
     The power-taking component  4  is mounted together with a car power-taking port (also referred as to cigar lighter, not shown in the drawings). According to industry standard, the car power-taking port has a cylindrical power-taking space, on a cylindrical wall of which a metal member used as a second connective component is disposed, while in an axial interior portion of which another metal member used as a first connective component is disposed. Therefore, the power-taking component  4  is designed to be inserted suitably into the car power-taking port and maintain reliable contact with both of the first and second connective components respectively such that power is supplied to the power-taking component. Power-taking is performed by inserting the power-taking component  4  into the car power-taking port. Accordingly, one end which is inserted into the power-taking port, of the power-taking component  4  is defined as an internal end, while the opposite end thereof is defined as an outer end. 
     For the power-taking component  4  to meet the above requirements, reference is also made to  FIGS. 2 and 3 . In a preferred embodiment of the invention, the power-taking component  4  is designed to have a main body ( 41 ,  43 ), a first power-taking electrode  42  and a second power-taking electrode  46 . The main body ( 41 ,  43 ) is composed of a cylindrical member  41  and a bottom cap  43  both of which are assembled together. The bottom cap  43  and cylindrical member  41  may be assembled together by means of screw, snap fit, and the like. As such, a first receiving space is formed by assembling of the cylindrical member  41  and bottom cap  43 . In addition, the first receiving space is also part of the power-taking space of the power-taking port. In the present invention, the first receiving space  81  also receives other components of the invention, in addition to the first power-taking electrode  42  and second power-taking electrode  46 . 
     A through hole  430  is defined at an axial location of the bottom cap  43 . The through hole  430  serves to contain the first power-taking electrode  42  such that the electrode  42  will pass the hole  430  and then be connected electrically and physically with the first connective member of the power-taking port. The detailed construction of the first power-taking electrode  42  and assembling relationship of it with the bottom cap  43  are discussed hereinafter. As shown in  FIG. 3 , a lateral hole is defined at a cylindrical wall of the cylindrical member  41  through which the second power-taking electrode  46  passes in order that the electrode  46  will be connected with a second connective member of the power-taking port electrically and physically. The second power-taking electrode  46  is positioned on a locating member  461 . In addition, the locating member  461  is fixed to an inner wall of the power-taking component  4  so that the second power-taking electrode  46  is held on place. By this way, the second power-taking electrode  46  is prevented from dropping into interior of the first receiving space  81 . 
     Reference is made to  FIGS. 2-4 . The first power-taking electrode  42  is retractable and includes a sleeve  425 , a cylindrical spring  429 , a contacting member  423  and a circlip  421 . The contacting member  423  includes a first portion  4235  and a second portion  4231  having smaller diameter than the first portion  4235 . A circular groove is formed at a distal end of the second portion  4231 . Moreover, the outer diameter of the second portion  4231  is smaller than the inner diameter of the cylindrical spring  429 . One end of the sleeve  425  is opened and the other end thereof has a through hole defined therein. The second portion  4231  is inserted into the spring  429 . The second portion  4231  of the contacting member  423  together with the spring  429  is placed into the sleeve  425 . Part of the second portion  4231  runs outside the through hole of the sleeve  425 . In addition, the circlip  421  is fitted into the circular groove of the second portion  4231 , thus finishing assembling of the first power-taking electrode  42 . It is apparent that the sleeve  425  of the first power-taking electrode  42  is secured on the bottom cap  43  such that one end of the contacting member  423  is exposed, while the other end thereof comes into the first receiving space  81 . In this case, the contacting member  423  is capable of retract or extend when an axial force is applied thereon. When the force is applied axially toward the external end of the member  423 , the member  423  will urge the cylindrical spring  429  such that the spring  429  is compressed into the first receiving space  81 . When the force disappears, the contacting member  423  will return its original position under the resiliency of the spring  429 . The monitoring component of the present invention can be adapted to power-taking ports with power-taking space of different depth due to retractable configuration. 
     Therefore, according to a preferred embodiment of the invention, when designing the construction of the first receiving space  81 , we should consider providing a second receiving space  82  for receiving the contacting member  423 . The monitoring component of the onboard power-taking port of the invention is able to adapt to various power-taking ports with different depth due to retractable configuration of the first power-taking electrode  42 . However in another embodiment (not shown) of the invention, to adapt different depth of the power-taking ports, the length of the first power-taking electrode  42  is set to be constant. In addition, it is unnecessary for the electrode  42  to extend into the first receiving space  81 . In this situation, there is no need for providing a second receiving space  82 . 
     Referring to  FIGS. 2 ,  3  and  5 , to further utilize the first receiving space  81  with higher effectiveness, two circuit boards  32  are used as the carrier  32  for mounting the control circuit  6  of the invention. 
     As indicated by name, the control circuit  6  functions to perform signal processing and supply the processed signal to the display unit  31  to display the signal. A typical application of the monitoring component of the onboard power-taking port of the invention is configured as part of a tire pressure monitoring system (not shown). That is, take the monitoring component as a monitoring unit of the tire pressure monitoring system. Signal representing tire pressure and/or tire temperature transmitted by the tire pressure gauge of the tire pressure monitoring system, is received by the control circuit  6  via the antenna  5 , decoded, calculated, transformed into signal to be outputted by the display unit  31 , and then is displayed by the unit  31  connected with the control circuit  6 , thus realizing tire pressure monitoring. Here, to ensure that the antenna  5  can receive and transmit signal without malfunction, the display unit  31  should be able to display information without any obstacle. Consequently, it is not wise to arrange the display unit  31  close to the internal end of the power-taking component  4 . The rest components of the control circuit  6  can be totally secured onto the two circuit boards  32 . Of course, the number of the circuit boards  32  may be changed based on complexity of the control circuit  6 . For example, one, three or four or even more circuit boards  32  may be provided as long as there is no influence on space utilization. 
     The monitoring component of the power-taking port of the invention may also have other applications such as for monitoring temperature inside the car, automobile gas and the like. Similar to the above typical application, in these applications, the antenna  5 , control circuit  6  and display unit  31  may also be included and have the similar arrangement. Apparently, the monitoring component of the power-taking port of the invention has wide application. 
     In the present invention, the two circuit boards  32  contain part of the control circuit  6  respectively. The two circuit boards  32  are parallel with each other and are vertically disposed on the same plane of a supporting disc  33 . The two circuit boards  32  are also supported by a connective member  321  such that balanced stable relationship is maintained between the two boards  32 . The display unit  31  is secured on the other plane of the supporting disc  33 . An indicator lamp  310  may also be provided on an upper surface of the supporting disc  33 . Obviously, using the two planes of the supporting disc  33 , the display unit  31 , control circuit  6  and carrier  32  constitute a construction body  3 . The supporting disc  33  may function as a divider of the construction body  3 . In this case, the control circuit  6  and its carrier  32  are disposed into the first receiving space  81 , whereas the display unit  31  is disposed at the external end of the power-taking component  4 . 
     Reference is further made to  FIGS. 2 ,  3  and  5 . To assemble the construction body  3  and power-taking component  4  together, an extension portion  413  with larger diameter is formed on the external end of the cylindrical member  41  of the power-taking component  4 . A circular flange  410  is formed on the inner wall of the cylindrical member  41  at location between the extension portion  413  and a non-extension portion  415 . Alternatively, the flange  410  may also be formed by naturally extending outwardly the diameter of the extension portion  413 . The supporting disc  33  of the construction body  3  is located on the flange  410  directly or by an intermediate member. As such, the supporting disc  33  is held on the power-taking component  4 . Namely, the supporting disc  33  may be regarded as the divider of the construction body  3 . The control circuit  6  and circuit boards  32  are contained in the first receiving space  81 , and it is ensured that the screen of the display unit  31  is exposed and can display information. 
     It can be seen from the present preferred embodiment that the specific location of the flange  410  on the cylindrical member  41  may have influence on the entire length of the monitoring component and the depth of the entire first receiving space  81 . Based on the design illustrated in this preferred embodiment, the display unit  31  may have small thickness, and as such, when the monitoring component is inserted into the car power-taking port, the entire axial length of the monitoring component may be limited to be no longer than 1.5 times of the axial length of the power-taking space of the port. In another embodiment of the invention not shown, the length of the two circuit boards  32  is further shortened. In addition, the flange  410  is configured to be closer to the internal end of the power-taking component  4 . Accordingly, the axial length of the entire monitoring component can be further limited to be no longer than the axial length of the power-taking space of the car power-taking port when the monitoring component is inserted into the port. 
     As described above, the spatial relationship and assembling relationship between the construction body  3  and power-taking component  4  is determined. As shown in  FIGS. 2 and 3 , to realize connection of the first and second power-taking electrodes  42 ,  46  with the control circuit  6  so as to obtain electricity, the first power-taking electrode  42  is coupled to the control circuit  6  on the circuit board  32  via a first conductive piece  427 . Similarly, the second power-taking electrode  46  is coupled to the control circuit  6  of the circuit board  32 . It can be perceived that various other means may be used to realize connection of the first power-taking electrode  42  or second power-taking electrode  46 . As such, as the respective distance between the electrodes  42 ,  46  and circuit board  32  is short, there may be flexible designs for the first and second electrodes  42 ,  46 , and these designs should not be limited to the embodiments. 
     As illustrated above, in the present preferred embodiment, the first power-taking electrode  42  is designed to be retractable. Therefore, it is considered to provide a second receiving space  82  for accommodating the electrode  42 . Based on the aforementioned construction body  3 , in case that the carrier  32  is constructed of only one circuit board  32 , the second receiving space  82  into which the retractable first power-taking electrode  42  is contained, is thus defined by biasing the circuit board  32  away from the axis of the entire cylindrical member  41 . However, in case that the circuit board  32  is configured to have more components, these circuit boards  32  should be arranged around the supporting disc  33  and biased away from the axis. In this way, the second receiving space  82  is defined by a gap formed among these circuit boards  32  with the axis as the center of the gap. Apparently, the second receiving space  82  is part of the first receiving space  81  of the power-taking component  4 , and is also part of the power-taking space of the power-taking port. In other words, the above three spaces overlap partially with each other. 
     Reference is further made to  FIGS. 2 ,  3  and  5 . To protect the display unit  31  and according to a preferred embodiment of the invention, there is provided a protective cap  2  including a skirt portion  23  and a crown portion  21 . An opening  20  of which the shape is similar to that of the unit  31  is defined in the crown portion  21 . The protective cap  2  is secured to the supporting disc  33  by means of snap-fitting or screw. The screen of the display unit  31  is visible through the opening  20  after being assembled. 
     To reasonably arrange the antenna  5  so as to obtain the antenna mounting structure of the invention and make the antenna  5  receive and transmit signal with higher electrical performance, the antenna  5  should have a suitable length. In this preferred embodiment, a circular groove  40  is provided on an outer wall of the extension portion  413  of the external end of the cylindrical member  41 . Furthermore, to maintain the length of the groove, the groove  40  is designed to have threaded portion. Correspondingly, the antenna  5  connected with the control circuit  6  is also configured to have threaded portion. Moreover, the antenna  5  is inserted into the circular groove  40  for hiding purposes. The antenna  5  having this design brings better impedance match performance and stable signal receiving/transmitting, thus ensure reliable interconnection among the monitoring component and other related electronic devices. Therefore, generality of the monitoring component of the invention is enhanced significantly. In other embodiments of the invention not shown, the circular groove  40  may also be defined in an inner wall of the extension portion  413  so long as it is able to receive external signal. Alternatively, the circular groove  40  may also be defined in other locations as will be discussed below. 
     To further ensure assembling reliability of the entire construction body  3  and power-taking component  4  and according to a preferred embodiment, a lid  1  is provided which includes a crown portion  11  made of transparent material. In other words, the lid  1  has a transparent top surface through which the light from the display unit  31  can penetrate and then be seen. An assembling structure is formed between an end surface of the extension portion  413  of the external end of the cylindrical member  41  and skirt portion of the lid  1 . This assembling structure may be snap-fitting or screw structure. The lid  1  can be assembled with the extension portion  413  of the member  41  by above snap-fitting or screw manner, thus finishing the assembling of the entire monitoring component. Alternatively, to realize assembling between the lid  1  and member  41 , various other manners may be used. 
     Clearly, the lid  1  and protective cap  2  constitute cooperatively an enclosure member for covering and protecting the display unit  31 . It is noted that the specific structure of the enclosure member is not limited to the combination of the lid  1  and cap  2 . For example, the enclosure member may only include a lid  1 . Or, the lid  1  may be formed integrally with the protective cap. In a summary, the enclosure member may be designed with flexibility. 
     In an embodiment of the invention not shown, the axial length of the entire monitoring component is less than the axial length of the power-taking space of the car power-taking port. In this situation, there is no need to widen the diameter of the cylindrical member  41 . Limited by the inner diameter of the power-taking space, it is suitable to position the threaded antenna  5  into the threaded circular groove predefined in the inner wall or outer wall of the skirt portion  13  of the lid  1 . Selectively, the antenna  5  may also be disposed into the threaded circular groove predefined in the outer wall or inner wall of the skirt portion of the protective cap  2 . 
     Summarily, the antenna mounting structure for a monitoring component of an onboard power-taking port provided by the invention has the advantages of compact design, stable signal transmitting/receiving, and enhanced generality. In addition, the above antenna mounting structure may find its application in many fields where readable monitoring is needed such as tire pressure monitoring system.