Abstract:
A motor includes a stator including a rim portion and a central portion, with the rim portion including through holes and the center portion including a through opening. A rotor installed in the through opening of the stator includes at least one rotational shaft extending from a rotating center of the rotor, such that the rotor rotating as a result of electrical interaction between the stator and the rotor. A first bracket of the motor includes fastening bars that pass through the through holes of the stator, and include elastically deformable elastic fingers. A second bracket of the motor includes fastening holes formed in positions corresponding to the fastening bars of the first bracket and engaging the elastic fingers of the fastening bars.

Description:
BACKGROUND  
       [0001]     This description relates to a motor for generating a rotational force using electrical energy.  
         [0002]      FIG. 1  is a sectional view showing a disassembled state of a motor. As shown in the figure, the motor comprises a stator  1  and a rotor  2  penetrating the center of the stator  1 . A rotational shaft  3  of the rotor  2  passes through first and second brackets  4  and  5  and thus is rotatably supported therein. The stator  1  is joined to the first and second brackets  4  and  5 .  
         [0003]     To this end, a plurality of through holes  1   a,  through which screws  6  for fastening the first and second brackets  4  and  5  pass, are formed around a rim portion of the stator  1 . In addition, the stator  1  is formed with a through opening  1   b  through which the rotor  2  passes.  
         [0004]     The rotor  2  is installed in the opening  1   b  of the stator  1  in a state where a gap between an outer diameter of the rotor  2  and an inner diameter of the stator  1  is kept at a predetermined interval. Thus, the rotor  2  rotates about the center of the rotational shafts  3  by electrical interaction between the stator  1  and the rotor  2 .  
         [0005]     The first bracket  4  is formed with fastening holes  4   a,  through which the screws  6  pass, at positions corresponding to the through holes  1   a.  A through hole  4   b,  through which an end of the rotational shaft  3  passes, is formed in the center of the first bracket.  
         [0006]     The second bracket  5  is formed with fastening holes  5   a  at positions corresponding to the fastening holes  4   a  of the first bracket  4 . The screws  6  which sequentially passed through the fastening holes  4   a  of the first bracket  4  and the through holes  1   a  of the stator  1  are fastened to the fastening holes  5   a.  In addition, the second bracket  5  is formed with a through hole  5   b,  through which the other one of the rotational shafts  3 .  
         [0007]     In such a conventional motor, the screws  6  sequentially pass through the fastening holes  4   a  of the first bracket  4  and the through holes  1   a  of the stator  1  and are then fastened to the fastening holes  5   a  of the second bracket  5 , so that the first and second brackets  4  and  5  are fastened to each other.  
       SUMMARY  
       [0008]     In one general aspect, a motor includes a stator including a rim portion and a central portion, with the rim portion including through holes and the center portion including a through opening. A rotor installed in the through opening of the stator includes at least one rotational shaft extending from a rotating center of the rotor, such that the rotor rotating as a result of electrical interaction between the stator and the rotor. A first bracket of the motor includes fastening bars that pass through the through holes of the stator, and include elastically deformable elastic fingers. A second bracket of the motor includes fastening holes formed in positions corresponding to the fastening bars of the first bracket and engaging the elastic fingers of the fastening bars.  
         [0009]     Implementations may include one or more of the following features. For example, at least one of the first and second brackets may include a through hole through which the rotational shaft of the rotor extends. When the rotor includes two rotational shafts, both of the first and second brackets may include through holes through which the rotational shafts of the rotor extend.  
         [0010]     First and second seats may be formed on opposite ends of a through hole of the stator, and each of the seats may have an inner diameter larger than that of the through hole. A first seating protrusion may be formed on a proximal end of a fastening bar of the first bracket, with the first seating protrusion having an outer diameter corresponding to the inner diameter of the first seat of the stator. A second seating protrusion may be formed on an inlet of a fastening hole of the second bracket, with the second seating protrusion having an outer diameter corresponding to the inner diameter of the second seat of the stator. The seating protrusions of the first and second brackets may be tightly placed in the seats of the stator when the first and second brackets are fastened to each other.  
         [0011]     At least a pair of the elastic fingers may be provided on a distal end of a fastening bar, with the elastic fingers being spaced apart from each other in a direction perpendicular to a direction in which the fastening bar is inserted into the fastening hole. A catching protrusion may be provided on a distal end of each of the elastic fingers such that the catching protrusion engages a catching step in the fastening hole and is fastened to the second bracket when the fastening bar is fastened to the fastening hole. An inclined guide surface may be formed on an outer surface of each of the catching protrusions to be inclined at a predetermined angle and to taper toward a distal end of the catching protrusion, whereby the inclined guide surface allows the fastening bar to be easily fastened to the fastening hole. Each of the fastening holes of the second bracket may have a larger inner diameter portion and a smaller inner diameter portion, and the catching step may be formed at a portion where the inner diameter is changed.  
         [0012]     The first and second brackets may be made of synthetic resin.  
         [0013]     Such a motor may be securely assembled and may be used in a wet environment. Implementations may include a reduced number of parts relative to motors that do not employ fastening bars. Through use of the fastening bars and their associated elastic fingers, implementations of the motor may be assembled without requiring the use of screwdrivers or other tools. Moreover, in contrast to a connection provided by screws, the connection provided by fastening bars and fastening fingers is not subject to loosening, and associated noise or damage that may occur, as a result of vibrations caused by operation of the motor.  
         [0014]     Other features and advantages will be apparent from the following description, including the drawings, and the claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a sectional view showing a disassembled state of a prior art motor.  
         [0016]      FIG. 2  is a sectional view showing a disassembled state of a motor.  FIG. 3  is a sectional view showing an assembled state of the motor of  FIG. 2 . 
     
    
     DETAILED DESCRIPTION  
       [0017]     Referring to  FIGS. 2 and 3 , through holes  11  are formed around a rim portion of a stator  10 . The through holes  11  extend through the stator  10  in a direction in which a rotational shaft  30  of a rotor  20  extends. Fastening bars  41  formed on a first bracket  40  pass through the through holes  11 . Seats  13  are formed in opposite ends of each of the through holes  11 . The seats  13  are formed around inlets of the through holes  11 . An inner diameter of a seat  13  is larger than that of the through hole  11 .  
         [0018]     Further, the stator  10  is formed with a through opening  15  through which the rotor  20  passes. The through opening  15  is extends through the stator  10  in a direction in which the through holes  11  extend. In general, the center of the through opening  15  coincides with the center of the stator  10 .  
         [0019]     The rotor  20  is placed in the through opening  15  of the stator  10 . Rotational shafts  30  are provided at the rotational center of the rotor  20 . The rotational shafts  30  extend from opposite sides of the rotor  20 . In some implementations, only a single rotational shaft  30  is provided. The rotor  20  rotates about the center of the rotational shafts  30  by electrical interaction between the stator  10  and the rotor  20 . To this end, a gap between an outer surface of the rotor  20  and an inner surface of the through opening  15  is maintained at a generally constant size.  
         [0020]     In order to rotatably support the rotor  20  in the stator  10 , first and second brackets  40  and  50  are provided. In certain implementations, particularly implementations in which the motor is to be used in a wet place, the first and second brackets  40  and  50  may be made of synthetic resin. Other implementations, particularly those in which the motor does not need to be used in a wet place, may employ materials other than synthetic resin for the brackets.  
         [0021]     The first bracket  40  includes fastening bars  41  that extend from the first bracket. The fastening bars  41  pass through the through holes  11  of the stator  10  and are fastened to fastening holes  51  of the second bracket  50 . Thus, the fastening bars  41  are formed at positions corresponding to the through holes  11 . That is, the fastening bars  41  protrude in one direction from the positions on a rim portion of the first bracket  40 .  
         [0022]     At least two elastic fingers  42  are formed at a distal end of each fastening bar  41 . The elastic fingers can be elastically deformed in a direction perpendicular to the direction in which the fastening bar  41  extends into a fastening hole  51 . At least two of the elastic fingers  42  are formed to face each other across a space that is referred to as an elastic slot  43 .  
         [0023]     Each of the elastic fingers  42  is formed with a catching protrusion  44  at a distal end thereof. The catching protrusions  44  engage corresponding catching steps  52  in the fastening holes  51  when the fastening bars  41  are fastened to the fastening holes  51  of the second bracket  50 .  
         [0024]     An inclined guide surface  45  is formed on an outer surface of each of the catching protrusions  44 . The inclined guide surface  45  is formed to be inclined at a predetermined angle such that the catching protrusion  44  has a relatively smaller diameter at its distal end and a relatively larger diameter at its proximal end. The inclined guide surfaces  45  allows the fastening bars  41  to be easily inserted into the through holes  11  and the fastening holes  51 , and thus assist the elastic fingers  42  in being elastically deformed.  
         [0025]     In addition, seating protrusions  46  are formed on portions of the first bracket  40  corresponding to the proximal ends of the fastening bars  41 . Each of the seating protrusions  46  is formed to have substantially the same outer diameter as that of a seat  13  and is inserted into a seat  13  when the motor is assembled.  
         [0026]     A through hole  47 , through which one of the rotational shafts  30  passes, extends through the center of the first bracket  40 . The through hole  47  is designed so that the rotational shaft  30  is rotatably supported therein.  
         [0027]     The second bracket  50  is provided with the fastening holes  51  to which the fastening bars  41  are fastened. The fastening holes  51  are formed at positions corresponding to the fastening bars  41 . As noted above, the fastening holes  51  include catching steps  52  formed on the interior of the fastening holes  51 . When the fastening bars  41  are fastened to the fastening holes  51 , the catching protrusions  44  engage with the catching steps  52 . Each of the fastening holes  51  has a larger inner diameter portion and a smaller inner diameter portion, So that the catching step  52  is formed at a portion where the inner diameter is changed.  
         [0028]     In addition, an inlet of each fastening hole  51  of the second bracket  50  is formed with a seating protrusion  53 . The seating protrusions  53  engage the seats  13  of the stator  10  when the second bracket  50  is fastened to the stator  10 . Thus, the seating protrusion  53  has an outer diameter that matches the inner diameter of the seat  13 .  
         [0029]     A through hole  54 , through which the other one of the rotational shafts  30  passes, extends through the center of the second bracket  50 . The through hole  54  is designed so that the rotational shaft  30  is rotatably supported therein.  
         [0030]     The operation of the motor now will be described in detail.  
         [0031]     First, a process of assembling the motor will be described. Initially, the rotor  20  is positioned such that it can be placed within the through opening  15  of the stator  10 . In such a state, by moving the second bracket  50  toward the rotor or stator, the seating protrusions  53  of the second bracket  50  are placed on the seats  13  of the stator  10 . At this time, one of the rotational shafts  30  of the rotor  20  passes through the through hole  54  of the second bracket  50 .  
         [0032]     Next, the fastening bars  41  of the first bracket  40  are inserted into the through holes  11  of the stator  10 , and then are fastened to the fastening holes  51  of the second bracket  50 . At this time, the seating protrusions  46  of the first bracket  40  are placed on the seats  13  of the stator  10 , and the other one of the rotational shafts  30  passes through the through hole  47  of the first bracket  40 .  
         [0033]     Here, a process of fastening the fastening bars  41  to the fastening holes  51  of the second bracket  50  will be described. The elastic fingers  42  formed at the distal ends of the fastening bars  41  are inserted into the fastening holes  51  and first pass through the smaller inner diameter portions of the fastening holes  51 . At this time, the elastic slots  43  permit the elastic fingers  42  to be elastically deformed and thus to be brought into close contact with each other. Thus, the elastic fingers  42  and their catching protrusions  44  can pass through the smaller inner diameter portions of the fastening holes  51 .  
         [0034]     Once the catching protrusions  44  pass through the smaller inner diameter portions of the fastening holes  51 , the elastic fingers  42  shift back to their original state such that the catching protrusions  44  engage the catching steps  52  in the fastening holes  51 .  
         [0035]     Next, the operation of the assembled motor will be explained.  
         [0036]     When the motor is energized, the rotor  20  rotates by electrical interaction between the stator  10  and the rotor  20 . Thus, the rotational shafts  30  of the rotor  20  rotate. Since the rotational shafts  30  are rotatably supported in the through holes  47  and  54  of, respectively, the first and second brackets  40  and  50 , the rotor  20  also rotates with respect to the stator  10 . The portions of the rotational shafts  30  that protrude outward from the brackets  40  and  50  are connected to transmit a rotational force to other elements.  
         [0037]     As noted, the fastening bars formed on the first bracket are directly fastened to the fastening holes of the second bracket. Thus, since the additional parts for fastening the first and second brackets to each other are not needed, the motor may include a reduced number of parts and a correspondingly reduced manufacturing cost.  
         [0038]     In addition, the fastening bars are directly fastened to the fastening holes without using additional tools when the first and second brackets are fastened to each other. Thus, since the motor brackets can be easily fastened to each other, there is another advantage in that the process of assembling and disassembling the motor is simplified, and thus, the efficiency of the process is also improved.  
         [0039]     Further, since the catching protrusions of the fastening bars engage the catching steps of the fastening holes when the first bracket has been fastened to the second bracket, the first bracket cannot be removed from the second bracket without manipulating the elastic fingers  42 . Thus, the fastened state of the first and second brackets is secure and will not be loosened even when the motor is used for a long time. Thus, the motor has high durability and operational reliability.  
         [0040]     In addition, when the first and second brackets, as well as the fastening bars, are made of synthetic resin, the motor brackets and the fastening bars will not corrode even when the motor is used in a wet place. Therefore, higher reliability for the motor can be ensured.  
         [0041]     Other implementations are within the scope of the following claims.