Abstract:
A motor is disclosed. The motor can include: a rotor equipped with a shaft; a base, in which a housing hole is formed and which includes a housing support portion protruding along a periphery of the housing hole; a housing, which may be inserted in the housing hole to be supported by the housing support portion and in which a through-hole is formed so that the shaft may be inserted in one side of the through-hole; and a rotor support, which may be inserted into the other side of the through-hole and in which a support indentation is formed to rotatably support the shaft. This motor can be manufactured by a simple process at a low manufacturing cost.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of Korean Patent Application No. 10-2009-0042693, filed with the Korean Intellectual Property Office on May 15, 2009, the disclosure of which is incorporated herein by reference in its entirety. 
       BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present invention relates to a motor. 
         [0004]    2. Description of the Related Art 
         [0005]    Spindle motors are widely used in electronic products such as computer CD drives that require high-precision rotations. Despite its small size, the spindle motor allows high-speed rotations and precision control, as well as low power consumption, and because of these benefits, the use of the spindle motor is expected to increase continuously. 
         [0006]    A typical spindle motor includes a rotor and a stator, which supports the rotational movement of the rotor. 
         [0007]    A spindle motor according to the related art may be structured to have the rotor rotatably supported on the stator that includes a housing coupled to a base plate by way of caulking. 
         [0008]    The manufacture of the spindle motor may include processing the housing with high-strength brass in order to accurately align the centers of the stator and the rotor. This, however, may be one of the factors that increase costs. 
         [0009]    Also, the operation of coupling the housing to the base plate by caulking the lower surface of the housing can entail inconvenient processes. In addition, there is a risk of misalignment between the centers of the stator and the rotor occurring during the caulking process. 
         [0010]    To resolve these drawbacks, a structure of inserting a cup-shaped housing into the base plate has been proposed, with the shaft of the rotor inserted in the cup-shaped housing. In this arrangement, however, the shaft may be subject to tilting, when the housing coupled to the base plate is tilted. Also, the sizing operation, for modifying the inner diameter of a bearing fitted into the housing, can be more difficult. 
       SUMMARY 
       [0011]    An aspect of the invention provides a motor that can be manufactured by a simple process at a low cost. 
         [0012]    Another aspect of the invention provides a motor in which the shaft is prevented from tilting and in which the sizing operation for the inner diameter of the bearing is facilitated. 
         [0013]    Yet another aspect of the invention provides a motor that includes: a rotor equipped with a shaft; a base, in which a housing hole is formed and which includes a housing support portion protruding along a periphery of the housing hole; a housing, which may be inserted in the housing hole to be supported by the housing support portion and in which a through-hole is formed so that the shaft may be inserted in one side of the through-hole; and a rotor support, which may be inserted into the other side of the through-hole and in which a support indentation is formed to rotatably support the shaft. 
         [0014]    The housing and the housing support portion can have a fit tolerance, and the housing can be coupled to the base by a press fit. 
         [0015]    The housing support portion can protrude from one side of the base, and the housing can include a flange being in contact with the other side of the base. 
         [0016]    A base curb portion having a larger inner diameter can be formed in the housing hole to hold the flange. 
         [0017]    An adhesive can be included between the housing and the base. 
         [0018]    An exterior curb portion having a smaller outer diameter can be formed on a perimeter of the housing, while the motor can further include an electromagnet that is supported by the exterior curb portion. 
         [0019]    The rotor support and the through-hole in the housing can have a fit tolerance, and the rotor support can be coupled to the housing by a press fit. 
         [0020]    A support surface can be formed on the rotor support along a periphery of the support indentation, and the motor can further include a stopper, which may rest on the support surface and which may be coupled to the shaft, to prevent the shaft from becoming detached. 
         [0021]    The rotor support can be a flat element that includes a center portion, which may form the support surface, and an outer portion, which may be curved to provide surface contact with an inner perimeter of the housing. The support indentation can be formed as a recess in the center portion. 
         [0022]    An interior curb portion having a larger inner diameter can be formed in the through-hole of the housing to support the rotor support, which may be inserted from the other side of the through-hole. Here, the stopper can be interposed between the interior curb portion and the rotor support. 
         [0023]    The motor can further include a bearing between the shaft and the housing, in which case the stopper can be interposed between the bearing and the rotor support. 
         [0024]    The base can be a flat element, including a flange-like housing support portion that is being in surface contact with an outer perimeter of the housing. 
         [0025]    In certain embodiments, the motor can further include a thrust washer inserted in the support indentation of the rotor support and interposed between the shaft and the rotor support. 
         [0026]    In certain embodiments, at least one of the base, the housing, and the rotor support can be press-formed. 
         [0027]    Additional aspects and advantages of the present invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]      FIG. 1  is a cross-sectional view of a motor according to an embodiment of the invention. 
           [0029]      FIG. 2  is an exploded view of a stator in a motor according to an embodiment of the invention. 
           [0030]      FIG. 3  is a magnified view illustrating how a housing is coupled in a motor according to an embodiment of the invention. 
           [0031]      FIG. 4  and  FIG. 5  are cross-sectional views illustrating height adjustments in a motor according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    Certain embodiments of the invention will be described below in more detail with reference to the accompanying drawings. 
         [0033]      FIG. 1  is a cross-sectional view of a motor according to an embodiment of the invention.  FIG. 2  is an exploded view of a stator in a motor according to an embodiment of the invention, and  FIG. 3  is a magnified view illustrating how a housing is coupled in a motor according to an embodiment of the invention.  FIG. 3  provides a magnified view of portion A in  FIG. 1 . 
         [0034]    A motor according to an embodiment of the invention may include a rotor  1 , a base  10 , a housing  20 , and a rotor support  30 . The base  10 , the housing  20 , and the rotor support  30  may be included as parts of the stator, which supports the rotation of the rotor  1 . 
         [0035]    The rotor  1  is the part that rotates, and can include a shaft  2  that serves as the central axis of the rotation. 
         [0036]    As illustrated in  FIG. 1 , the rotor  1  of this embodiment may include the shaft  2 , and a hub  3  that is coupled to the shaft  2  to support the rotating body. A permanent magnet  4 , which may be arranged in correspondence with an electromagnet  70  equipped on the stator, may be coupled to the hub  3 . The permanent magnet  4 , together with the electromagnet  70 , may generate the driving force that rotates the rotor  1 . 
         [0037]    The base  10  is the part that generally supports the motor, and in certain examples, the base  10  may support the housing  20 , which in turn may support the rotor  1 . Accordingly, a housing hole  12 , through which the housing  20  can be inserted, may be formed in the base  10 . Also, a housing support portion  14  for supporting the housing  20  may protrude along the periphery of the housing hole  12 . 
         [0038]    Here, the base  10  can be a flat element. Using a press forming process, such as burring, etc., a housing support portion  14  shaped as a curved flange can be formed on the plate-like base  10  such that the housing support portion  14  is kept in surface contact with the outer perimeter of the housing  20 . 
         [0039]    Also, a base curb portion  16 , which has an increased inner diameter, can be formed in the base  10  to hold the flange  24  of the housing  20 , which will be described later in more detail. The base curb portion  16  can be formed by a press forming process, such as expanding, etc. 
         [0040]    As illustrated in  FIG. 2 , a flange-like housing support portion  14  may be formed on the base  10  according to this embodiment. The housing support portion  14  shaped as a flange may be curved such that the housing support portion  14  protrudes towards one side of the base  10 . Also, a base curb portion  16  may be formed in the housing hole  12 , towards the other side of the base  10 . This particular embodiment presents a housing support portion  14  that surrounds and supports the outer perimeter of the housing  20 . However, the invention is not thus limited, and housing support portion  14  can be implemented in various forms that are capable of partially supporting the outer perimeter of the housing  20 . 
         [0041]    The housing  20  may be coupled to the rotor support  30 , which will be described later in more detail, to rotatably support the rotor  1 . To this end, the housing  20  may be inserted in the housing hole  12  of the base  10  to be supported by the housing support portion  14 , as illustrated in  FIG. 1 . 
         [0042]    Here, the outer perimeter  20   a  of the housing  20  and the inner perimeter  10   a  of the housing support portion  14  can have a fit tolerance, so that the housing  20  may be coupled to the base  10  by a press fit, as illustrated in  FIG. 2 . 
         [0043]    Also, in order to securely couple the housing  20  to the base  10 , a flange  24  can be formed on the housing  20 , with the flange  24  placed in contact with the other side of the base  10 . As illustrated in  FIG. 3 , the housing  20  on which the flange  24  is formed may be supported by the housing support portion  14  and the other side of the base  10 . Thus, the housing  20  coupled to the base  10  can be effectively prevented from tilting, whereby tilting can be prevented also for the shaft of the rotor  1  supported by the housing  20 . The flange  24  can be formed using a press forming process, such as flanging, etc. This particular embodiment presents a flange  24  that has an annular shape formed along the outer perimeter of the housing  20 . However, the invention is not thus limited, and the flange  24  can be implemented in various forms, such as in the form of partially protruding portions formed along the outer perimeter of the housing  20 . 
         [0044]    Furthermore, to securely couple the housing  20  to the base  10 , an adhesive  80  can be applied between the housing  20  and the base  10 . In this embodiment, as illustrated in  FIG. 3 , a space, in which the adhesive  80  may readily be applied, may be formed between the flange  24  and the base curb portion  16 . 
         [0045]    Also, a through-hole  22  may be formed in the housing  20 . The shaft  2  of the rotor  1  may be inserted in one side of the through-hole  22 , so that the housing  20  may support the shaft  2 . 
         [0046]    As illustrated in  FIG. 1 , a bearing  60  can be interposed between the shaft  2  and the housing  20 , to facilitate the rotation of the shaft  2 . In this case, the housing  20 , which is shaped as a tube, may facilitate the sizing operation for modifying the inner diameter of the bearing  60 . Since the inner diameter is decreased as the bearing  60  is pressed into the housing  20 , a sizing operation of modifying the inner diameter by inserting a sizing rod may be required. With the housing  20  shaped as a tube, the sizing rod for modifying the inner diameter of the bearing  60  can be inserted more easily. 
         [0047]    An interior curb portion  26  having an increased inner diameter can be formed in the through-hole  22 , so that the rotor support  30  may be supported. The interior curb portion  26  can be formed by a press forming process, such as expanding, etc. 
         [0048]    In this embodiment, an exterior curb portion  28  having a decreased outer diameter can be formed on the outer perimeter of the housing  20 , enabling the housing  20  to support the electromagnet  70 . The exterior curb portion  28  can be formed by a press forming process, such as necking, etc. 
         [0049]    The rotor support  30  may be coupled with the housing  20  to rotatably support the rotor  1 , and may include a support indentation  32  that supports the shaft  2  of the rotor  1 . As illustrated in  FIG. 1 , the rotor support  30  may be inserted in the other side of the through-hole  22  of the housing  20 , to be coupled with the housing  20 . 
         [0050]    As illustrated in  FIG. 2 , the outer perimeter  30   a  of the rotor support  30  and the inner perimeter  20   b  of the housing  20  can have a fit tolerance, so that the rotor support  30  may be coupled to the housing  20  by a press fit. 
         [0051]    To prevent the shaft  2  from becoming detached, the motor according to this embodiment can further include a stopper  40  coupled to an indentation  2   a  in the shaft  2 . The stopper  40  in this particular embodiment may be shaped as a flat element having a coupling hole  42  and may be fitted onto the shaft indentation  2   a . As the rotor  1  rotates and begins to rise, the stopper  40 , supported by the stator, can prevent the rotor  1  from becoming detached. 
         [0052]    As illustrated in  FIG. 2 , a support surface  34   a , on which the stopper  40  may be placed, can be formed on the rotor support  30 , along the periphery of the support indentation  32 . 
         [0053]    In particular, the rotor support  30  can be made as a single integrated piece. To be more specific, the rotor support  30  can be a flat element that includes a center portion  34 , which may form the support surface  34   a , and an outer portion  36 , which may be curved to provide surface contact with the inner perimeter of the housing  20 . The support indentation  32  can be formed as a recess in the center portion  34 . In this case, the rotor support  30  can be formed by a press forming process, such as coining, drawing, etc. 
         [0054]    As shown in  FIG. 1 , the stopper  40  can be supported by being interposed between the interior curb portion  26  of the housing  20  and the rotor support  30 , described above. 
         [0055]    Also, as shown in  FIG. 1 , the stopper  40  can be supported by being interposed between the bearing  60  and the rotor support  30 , described above. To reduce the amount of heat and the degree of resistance created by the friction between the shaft  2  and the rotor support  30 , the motor according to this embodiment can further include a thrust washer  50  between the shaft  2  and the rotor support  30 . As illustrated in  FIG. 1 , the thrust washer  50  may be inserted in the support indentation  32  of the rotor support  30 . 
         [0056]    As described above, the base  10 , housing  20 , and rotor support  30  of a motor according to an embodiment of the invention can be formed by press forming, and can be coupled together sequentially by press-fitting. Thus, the procedures for processing and assembly can be simplified, and manufacturing costs can be reduced. The structure implemented by press forming and press-fitting also provides high precision in its specifications. Accordingly, various materials can be employed for the components of the motor, without having to use expensive materials, such as brass, etc. 
         [0057]    Also, as the housing  20  may be firmly secured to the base  10 , the motor according to this embodiment may provide a stable shaft system, in which the shaft is prevented from tilting. 
         [0058]    The motor may also provide the advantage of easy height adjustment, for an increased degree of freedom in design. 
         [0059]      FIG. 4  and  FIG. 5  are cross-sectional views illustrating height adjustments in a motor according to an embodiment of the invention. 
         [0060]    As illustrated in  FIG. 4  and  FIG. 5 , the mounted height H 1  of the shaft  2  in relation to the base  10  can be adjusted by adjusting the depth to which the rotor support  30  is pressed. In this way, the height of the rotor  1  with respect to the base  10  may readily be adjusted. 
         [0061]    Also, the protrusion height H 2  of the housing  20  from the base  10  can be adjusted, using the base curb portion  16 . Thus, by adjusting the mounted height H 1  of the shaft  2  and the protrusion height H 2  of the housing  20 , the overall height of the motor may readily be adjusted. 
         [0062]    As set forth above, certain aspects of the invention provide a motor that can be assembled by sequentially fitting components formed by press forming, whereby the manufacturing process of the motor can be simplified, and manufacturing costs can be reduced. 
         [0063]    Certain aspects of the invention provide a motor in which the housing that supports the rotor is firmly secured, so that the shaft of the motor can be prevented from tilting. 
         [0064]    Also, certain aspects of the invention include a tube-shaped housing by which the sizing operation for the inner diameter of the bearing inserted in the housing may be facilitated. 
         [0065]    While the spirit of the invention has been described in detail with reference to particular embodiments, the embodiments are for illustrative purposes only and do not limit the invention. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the invention. 
         [0066]    Many embodiments other than those set forth above can be found in the appended claims.