Patent Publication Number: US-2016226362-A1

Title: Flat Linear Vibration Motor

Description:
FIELD OF THE INVENTION 
     This invention relates to a type of vibration motor, especially a type of flat linear vibration motor which is used for those portable consumption electronic products. 
     DESCRIPTION OF RELATED ART 
     With the development of electronic technology, portable consumption electronic products become more and more popular, such as cellphones, handheld game player, navigation device, or handheld multimedia recreation equipment, etc., vibration motor is usually used on these electronic products to make system feedback, such as cellphones call reminders, SMS tips, navigation tips, and vibration feedback of game players, etc. Such wide application requires that the vibration motor must be of high performance and long service life. 
     The vibration motor of related technology includes a housing, a vibrator unit received in the housing and a spring unit used to suspend the vibrator unit within the housing and provide restoring force and localization guidance to the vibrator unit. But the vibrator unit of the vibration motor with this kind of structure shakes easily and spring will be failed and worn elastically due to long-term use, so the performance and service life of motor will be influenced. In addition, the driving coils of the vibration motor with this kind of structure are provided on one side face of vibrator unit. This kind of assembly mode makes the insufficient electromagnetic driver force generated by driving coil. 
     Therefore, it is necessary to provide a new flat linear vibration motor to solve the problems mentioned above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiment can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is an isometric and exploded view of a flat linear vibration motor in accordance with an exemplary embodiment of the present disclosure. 
         FIG. 2  is a cross-sectional view of the flat linear vibration motor in  FIG. 1  taken along a longer axis thereof. 
         FIG. 3  is a partial assembled view of the flat linear vibration motor shown in  FIG. 1 . 
         FIG. 4  is a first cross-sectional view of the flat linear vibration motor shown in  FIG. 1  taken along a shorter axis. 
         FIG. 5  is a second cross-sectional view of the flat linear vibration motor shown in  FIG. 1 , taken along the shorter axis. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT 
     The present invention will hereinafter be described in detail with reference to an exemplary embodiment. It should be understood the specific embodiments described hereby is only to explain this disclosure, not intended to limit this disclosure. 
     As shown in  FIGS. 1-3 , a flat linear vibration motor  1  in accordance with an exemplary embodiment of the present disclosure includes a housing  10  forming an accommodation space  100 , a first magnet  11  received in the accommodation space  100  and fixed in the housing  10 , a vibrator unit  12  suspended in the housing  10  and a second magnet  13  fixed in the housing  10 . The first magnet  11 , the vibrator unit  12  and the second magnet  13  are arranged one by one along a vibration direction X-X of the vibrator unit  12 . 
     The housing  10  includes an upper shell  101  and a lower shell  102  cooperating with the upper shell  101  to form the accommodation space  100 . The lower shell  102  includes a bottom wall  1020  and a side wall  1021  extending from the bottom wall  1020 . The first magnet  11  and the second magnet  13  are fixed respectively in the side wall  1021  of the lower shell  102  and disposed in an inner side face of the side wall  1021 . The upper shell  101  can be plate-shaped or the same shape as that of following lower shell  102 . Various shapes can be set according to concrete need. 
     Referring also to  FIG. 4 , the vibration motor  1  further includes a ring driving coil  14  provided circularly in a periphery of the vibrator unit  12  for driving the vibrator unit  12  to vibrate repeatedly along a vibration direction X-X. The vibration motor  1  includes engaging assemblies  15 ,  16  provided between the vibrator unit  12  and the housing  10  for suspending the vibrator unit inside the housing  10  to make the vibrator unit  12  to move along the vibration direction X-X. 
     The vibrator unit  12  includes a long-strip clump weight  120 , a third magnet  121 , a driving magnet  122  and a fourth magnet  123  fixed in the clump weight  120 . The third magnet  121  is such configured that a magnetic pole thereof is similar to an adjacent magnetic pole of the first magnet. The fourth magnet  123  is such configured that a magnetic pole thereof is similar to an adjacent magnetic pole of the second magnet  13 . By utilizing the repelling force generated between the first magnet  11  and the third magnet  121  and the repelling force generated between the second magnet  13  and the fourth magnet  123 , the first magnet  11  and the second magnet  13  can limit the displacement of the vibrator unit  12  on the vibration direction X-X of the vibrator unit and provide restoring force to the vibrator unit  12 . 
     The clump weight  120  provides slots  1203  along two ends of the vibrator unit  12  along the vibration direction X-X. The third magnet  121  and the fourth magnet  123  are fixed respectively in slots  1203 . The clump weight  120  corresponds the driving magnet  122  and depresses and forms one bearing part  1204  and a ring groove  1205  encircling the bearing part  1204 . The driving magnet  122  sheathed and fixed in the bearing part  1204  and received in the ring groove  1205 . In this way, the outside surface of the driving magnet  122  will not exceed the outer surface of the clump weight  120 . 
     The clump weight  120  includes a first outer side face  1201  and a second outer side face  1202  extending along the vibration direction X-X of the vibrator unit  12 . Optionally, the first outer side face  1201  is parallel to the second outer side face  1202 . The housing includes a first inner side face  103  and a second inner side face  104  extending along the direction of vibration X-X of vibrator unit. Similarly, the first inner side face  103  and the second inner side face  104  are set mutually parallel in the embodiment. The engaging assemblies  15  and  16  include a first engaging assembly  15  located between the first outer side face  1201  and the first inner side face  103  and a second engaging assembly  16  located between the second side face  1202  and the second inner side face  104 . 
     Referring to  FIG. 4 , the first engaging assembly  15  includes a first guide rail part  151  fixed in the first outer side face  1201  provided with a first guide rail  1510 , and a first guide groove part  152  fixed in the first inner side face  103  and cooperating with the first guide rail part  151  for forming a first guide groove  1520 . The second engaging assembly  16  includes a second guide rail part  161  fixed on the second outer side face  1202  provided with a second guide rail  1610 , and a second guide groove part  162  fixed in the second inner side face  104  which cooperates with the second guide rail part  161  to set a second guide groove  1620 . 
     By virtue of the cooperation between the first and second guide rails  1510  and  1610  and the first and second guide grooves  1520  and  1620 , the vibrator unit  12  is suspended in the housing  10  and moveable along the vibration direction X-X. 
     In this embodiment, the first and the second guide rails  1510  and  1610  are magnetic guide rails. The first and second guide groove  1520  and  1620  are magnetic guide groove. The first and second guide groove  1520  and  1620  are respectively sheathed and set at outer side of the first and second guide rails  1510  and  1610 . Moreover, the first and the second guide rails  1510  and  1610  are respectively set with the first and the second guide groove  1520  and  1620  as per opposite homopolarity. The settings above make the first and second guide rails  1510  and  1610  magnetically suspend inside the first and second guide groove  1520  and  1620 . Circular-arc guide rails is adopted preferably for the first and second guide rails  1510  and  1610 . The first and second guide groove  1520  and  1620  present the circular-arc guide groove that matches the first and the second guide rails  1510  and  1610 . 
     Referring to  FIGS. 2 and 5 , the driving magnet  122  is a ring magnet. The ring driving coil  14  matches the shape of the ring driving magnet  122 . Optionally, radial magnetization is adopted for the driving magnet  122 , After being powered on, the driving coil  14  in the magnetic field driven by the driven magnet  122  is affected by the action of Ampere force. After the driving magnet  122  is affected by the counter force of Ampere force, the vibrator unit  12  is promoted to vibrate repeatedly along the vibration direction X-X. The driving magnet  122  is not limited to the ring magnet. It can be divided into four pieces of magnets affixed in periphery of the clump weight  120  respectively to reach the same effect as the ring magnet does. Use the inventive concept of the invention and the protection scope required by the invention. 
     The flat linear vibration motor  1  provided by the invention utilizes the restoring force provided by the repelling force between magnet and utilizes prismatic pair to provide localization guidance for vibrator of unit  12  and set the driving coil  14  as ring and set circularly in periphery of driven magnet  122  to improve the utilization of magnet to avoid the effect on performance of motor and service life due to the failure or wear of spring parts of traditional vibration motor to promote the performance of vibration motor  1  efficiently. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present embodiment have been set forth in the foregoing description, together with details of the structures and functions of the embodiment, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.