Abstract:
Disclosed herein is a 3-dimension range finder sensor, the proposed range finder sensor including a mirror reflecting emitted light and incident light; a mirror support tiltably supporting the mirror; a cylindrical body coupling the mirror support to its one side and being of a hollow shape in at least one part to allow the emitted light and the incident light to pass therethrough; a horizontal drive motor installed on a base for supportively rotating the cylindrical body; a link device connected to the mirror for tilting the mirror; a vertical drive motor disposed at a lateral surface of the horizontal drive motor on the base; and a power transmission part interposed between the vertical drive motor and the link device and transmitting the power of the vertical drive motor to the link device for the link device to tilt the mirror.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit under 35 U.S.C. §119 of Korean Application No. 10-2009-0067680, filed Jul. 24, 2009, which is hereby incorporated by reference in its entirety. 
       BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a three dimension range finder sensor, more particularly to a 3-D range finder sensor capable of reducing the size of a product through the structure improvement of a horizontal drive system and a vertical drive system. 
         [0004]    2. Description of the Related Art 
         [0005]    The range finder sensor comprised of a light source, a rotating body, and a sensor detects the signal through a sensor, performs a series of numerical calculations and determines a distance in a case light emitted from a light source hits an object and turns back again. The rotating body helps determine a distance to the object within a given angle boundary by changing the angle of emitted light and incident light. 
         [0006]    Such a range finder sensor is generally in a structure of performing a distance determination of a first dimension section. That is, it can scan an object in a horizontal direction. In order to implement a 3-D range finder sensor that can scan in a horizontal direction as well as a vertical direction, a mirror within an LRF (Laser Range Finder) structure needs to move in a horizontal direction as well as in a vertical direction. In order to move the mirror in a horizontal direction and in a vertical direction, a horizon drive system and a vertical drive system are used. 
         [0007]    The conventional three dimension range finder sensor uses a spindle motor as a horizontal drive system, and uses a stepping motor as a vertical drive motor. The spindle motor is comparatively disposed in the lower part, and the stepping motor is disposed in the upper part of the spindle motor. 
         [0008]    However, there lies a problem in the prior-art 3-D range finder sensor that a support part of a hollow axis fixed at a spindle motor, as a horizontal drive part for mirror rotation, is placed on the lower part of a product so that the run-out of the upper part is relatively great to which the mirror is combined. 
         [0009]    Also, due to a structure in which a hollow-type stepping motor as a vertical drive part for the tilting drive of a mirror is stacked over a spindle motor, a product height in the prior-art 3-D range finder sensor increases to make it difficult to miniaturize the sensor. 
         [0010]    Also, as another problem in the prior-art 3-D range finder sensor, there is great friction load because of a number of power transmission components from a rotor to a screw axis in the vertical drive part, and since a portion in which the vertical drive part is connected to the horizontal drive part is an outer ring rotation type that is attached to a bearing outer racing, it is difficult to provide a space safely supporting the sliding of a screw axis so that the variation of the pitch angle of the mirror becomes larger. 
         [0011]    The present invention has been devised to overcome the above-mentioned problems, and it is a technical subject to provide a 3-dimensional range finder sensor configured to reduce the run-out of a product through the structure improvement of a horizontal drive system and a vertical drive system in order to move a mirror, to be advantageous for a mirror to obey an angle control angle, and to reduce a product size through the appropriate employment of an effective space. 
         [0012]    Technical challenges to be achieved by the present invention are not limited to the above-mentioned technical challenge, and other not-mentioned technical challenges would be clearly understood by those skilled in the art from the accompanying recitation. 
       BRIEF SUMMARY 
       [0013]    To solve the aforementioned challenges, a 3-dimension range finder sensor according to the present invention comprises: a mirror reflecting emitted light and incident light; a mirror support tiltably supporting the mirror; a cylindrical body coupling the mirror support to its one side and being of a hollow shape in at least one part to allow the emitted light and the incident light to pass therethrough; a horizontal drive motor installed on a base for supportively rotating the cylindrical body; a link device connected to the mirror for tilting the mirror; a vertical drive motor disposed at a lateral surface of the horizontal drive motor on the base; and a power transmission part interposed between the vertical drive motor and the link device and transmitting the power of the vertical drive motor to the link device for the link device to tilt the mirror. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a perspective view indicating a 3-dimension range finder sensor according to one embodiment of the present invention; 
           [0015]      FIG. 2  is a plan view indicating a 3-dimension range finder sensor according to one embodiment of the present invention; and 
           [0016]      FIG. 3  is a cross section view taken along line I-I of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Hereinafter, a 3-dimension range finder sensor according to one embodiment of the present invention will be described in detail with reference to the annexed drawings. 
         [0018]    In describing the present invention, the size, shape, etc. of components shown in the drawings may be exaggerated or simplified for the sake of clarity and conveniences. Also, specially defined terms in consideration of the construction and function of the present invention may be varied according to the intention and custom of a user and an operator. Such terms should be interpreted into the meaning and scope matching to the technical spirit of the present invention based on recitations throughout the entire specification. 
         [0019]      FIG. 1  is a perspective view indicating a 3-dimension range finder sensor according to one embodiment of the present invention,  FIG. 2  is a plane view indicating a 3-dimension range finder sensor, and  FIG. 3  is a cross section view taken along line I-I. 
         [0020]    As shown in  FIG. 1 , a 3-dimension range finder sensor according to an embodiment of the present invention largely includes a main body  110  and an LRF (Laser Range Finder) structure  120 . In the main body  110 , a light reception device sensing incident light as an optical signal, a light focusing lens focusing inputted incident light into the light reception device, and a light emitting device emitting light using a laser are installed. 
         [0021]    Light produced in the light emitting device is reflected by the mirror  131  and emits outwards as a signal optic. A direction of emitted light is varied according to the rotation position and inclination of the mirror  131 . When the emitted light hits an object and turns back as a signal optic, the signal optic is reflected by the mirror  131 , incident on the interior of the main body  110 , through the light focusing lens and then incident on the light reception device. As such, the 3-dimension range finder sensor  100  according to one embodiment of the present invention may perform a scanning that illuminates emitting light and radiates through the mirror  131 , and focuses the incident light, which hitting the object and turning back, through the mirror  131 , as a normal one does. 
         [0022]    The LRF structure  120  may perform a 3-dimension range finder (range finder) through the rotation and the inclination of the mirror  131 . The mirror  131  is supported by a link device  134  and a mirror support axis  133  combined at a pair of a mirror support  132 , possibly capable of a tilting operation. Such a mirror assembly  130  may be coupled to the upper part of a rotating body  140  to freely rotate with the rotating body  140 . 
         [0023]    At this time, the mirror  131  is tilted by the vertical movement of the link device  134 , so that an elevation bearing  166  installed with the link device  134  is provided to go up/down along the rotating body  140 . That is, the cylindrical body  140 , the pair of mirror supports  132 , the mirror support axis  133  and the link device  134  are connected to each other and rotate around a same axis, and the lower end part of the link device  134  is connected to the inner ring of the elevation bearing  166 , and the inner ring of the elevation bearing  166  is elevatingly inserted around the outer circumference of the rotating body  140 . 
         [0024]    The outer ring of the elevation bearing  166  is integrated with a bracket  163  of a vertical movement body  162 , and a nut member  168  is fixed in the bracket  163 . The nut member  168  and the screw axis  167  are combined with a screw. When a screw axis  167  is rotated, the nut member  168 , the bracket  163 , the outer circumference and inner ring of the elevation bearing  166 , and the link device  134  are going up/down, thereby tilting the mirror  131 . 
         [0025]    The screw axis  167  is connected to the drive axis  161  of the vertical drive motor  160 , and the vertical drive motor  160  and the horizontal drive motor  150  are separately controllable. According to the rotation angle of the vertical drive motor  160  and the horizontal drive motor  150 , the rotation and tilting of the mirror  131  are simultaneously possible. 
         [0026]    The horizontal drive motor  150  is installed in the base  111 , supporting and rotating, the cylindrical body  141 . The link device  134  is connected to the mirror  131 , tilting the mirror  131 . The vertical drive motor  160  is disposed in the base  111  as the side surface of the horizontal drive motor  150 . The power transmission unit  170  is inserted between the vertical drive motor  160  and the link device  134 , and delivers the power of the vertical drive motor  160  to the link device  134  to enable the link device  134  to tilt the mirror  131 . 
         [0027]    Such a power transmission unit  170  includes an elevation bearing  166 , a screw axis  167 , and a nut member  168 , is a power transmission means for the vertical movement of the link device  134 . 
         [0028]    The elevation bearing  166  is connected to the vertical drive motor  160  for rotating and vertically moving the link device  134 . Here, the inner ring of the elevation bearing  166  is slidingly inserted into the cylindrical body  141 , and is connected to the link device  134 , and the outer circumference of the elevation bearing  166  may be connected to the vertical drive motor  160 . 
         [0029]    The screw axis  167  is coupled to the drive axis  161  of the vertical drive motor  160 . The nut member  168  is screw-connected to the screw axis  167 , and is connected to the elevation bearing  166 , and it vertically moves the elevation bearing  166  by going up and down when the vertical drive motor  160  is rotated. 
         [0030]    The guide axis  164  guides the vertical movement of the link device  134 . The vertical drive motor  160  is disposed in the opposite side of the guide axis  164  with placing the cylindrical body  141  between them. Here, three of the guide axis  164  and the vertical drive motor  160  are in the periphery of the cylindrical body  141  with 90° interval. Because the vertical drive motor  160  is disposed at an unemployed void space of the tap part (the bottom-right edge of  FIG. 2 ) of the base  110 , the size of the apparatus may be reduced. The cylindrical body  141  is supported in both ends to be rotated by a pair of a rotating body support bearings  153  provided at the lower side of the elevation bearing  166 . The elevation bearing  166  is capable of freely going up/down because it is disposed at the upper side of the rotating body support bearing  153 . 
         [0031]    As shown in  FIGS. 1 through 3 , the rotating body  140  includes the cylindrical body  141  and a mirror support body  142 . Because the cylindrical body  141  is empty in its interior, emitted light or incident light through the interior of the cylindrical body  141  and through the mirror  131  may be transmitted to the main body  110 . The cylindrical body  141  is rotated by the horizontal drive motor  150 . The mirror support body  142  is formed at the upper part of the cylindrical body  141  and connected to a pair of mirror supports  132 . 
         [0032]    The horizontal drive motor  150  is supported by a motor support body  151 , and the motor support body  151  is coupled to a fixation body connected to the base  111 . In the inner side of the motor support body  151 , a pair of cylindrical support bearings  153  is installed at the upper/lower side with placing the horizontal drive motor  150  between them to support the cylindrical body  141  rotatingly. The horizontal drive motor  150  is disposed along the outer periphery surface of the cylindrical body  141  to rotate the cylindrical body  141 . 
         [0033]    The cylindrical body  141  may be rotated by the horizontal drive motor  150 , and it corresponds to the rotation axis of the horizontal drive motor  150 , and it can only rotate around the vertical axis of the horizontal drive motor  150 , restricted in a vertical movement. 
         [0034]    On the one hand, the vertical movement body  162  is supported to be slidingly moved by a plurality of guide axis  164  coupled to the motor support body  151 . The guide axis  164  is disposed in parallel to the cylindrical body  141 . An axis support member  165  is coupled to a bracket  163  of the vertical movement body  162 , and the guide axis  164  is inserted into this axis support member  165 . In the inner side of the vertical movement body  162 , an elevation bearing  166  supporting rotatingly the link device  134  supporting for the mirror  131  to have any pitch angle is installed. 
         [0035]    The vertical drive motor  160  is disposed at the outer side of the rotating body  140  and the horizontal drive motor  150 . That is, the vertical drive motor  160  is disposed at the outer edge part of the rotation body  140  and the horizontal drive motor  150 , so that it can reduce the product height compared to in a previous case a horizontal drive motor is installed over a vertical drive motor. At this time, the thrust of the vertical drive motor  160  is delivered to the mirror  131  through the screw axis  167  and the nut member  168 . 
         [0036]    The drive axis  161  of the vertical drive motor  160  penetrates the bracket  152  of the motor support body  151  at its end portion, and the end portion of the drive axis  161  is coupled to the screw axis  167 . The screw axis  167  is screw-coupled to the nut member  168  coupled to one side of the vertical movement body  162 . Thus, when the screw axis  167  is rotated, the nut member  168  moves in a vertical direction by an external force. By such an action of the screw axis  167  and the nut member  168 , the vertical movement body  162  shifts slidingly along the guide axis  164 . 
         [0037]    As such, because the rotation body  140  supporting the mirror assembly  130  rotates and shifts up and down by the horizontal drive motor  150  and the vertical drive motor  160 , the mirror  131  may rotate by 360° and move up/down and reflect emitted light and incident light. The following is an action where the mirror  131  moves by the horizontal drive motor  150  and the vertical drive motor  150 . 
         [0038]    In a case the horizontal drive motor  150  operates, a cylindrical body  141  rotatingly supported by a pair of rotation body support bearings  153  and the mirror support body  142  coupled at the upper side of the cylindrical body  141  rotate. In a case the mirror support body  142  rotates, a pair of mirror supports  132  coupled to the mirror support body  142  and the link device  134  connected to this and the inner ring of the elevation bearing  166  coupled to the link device  134  and also structures connected to the inner ring of the elevation bearing  166  rotate together. 
         [0039]    In the meantime, in a case the vertical drive motor  160  operates and the drive axis  161  rotates, the screw axis  167  coupled thereto rotates. In a case the screw axis  167  rotates, the nut member  168  coupled to the vertical movement body  162  moves vertically by its interaction to the screw axis  167 . At this time, the vertical movement body  162  shifts vertically with the nut member  168  along the guide axis  164 . 
         [0040]    As such, according to a 3-dimension range finder sensor  100  of an embodiment of the present invention, a vertical drive system for shifting the mirror assembly  130  in a vertical direction can be disposed at the outer side of the cylindrical body  141  separately from a horizontal drive system, thereby reducing the entire height. And, by guiding the vertical movement body  162  moving vertically by the vertical drive motor  160  using a plurality of guide axis  164 , the vertical movement body  162  can shift vertically safely. 
         [0041]    Also, by adopting the inner ring of the elevation bearing  166  as a connection bearing connecting the vertical drive part and the horizontal drive part in a rotation mode, the guide axis  164  or the nut member  168  may be provided as one or more sliding guide means in a fixed outer ring structure. And, the vertical drive system is supported at both ends by the guide axis  164  or the nut member  168 , thereby improving safeness upon a vertical drive. 
         [0042]    Also, an installation interval of a pair of rotation body support bearings  153  rotatingly supporting the cylindrical body  141  may be widened, thereby reducing the run-out of the cylindrical body  141 . Also, by employing a void space of a product outer edge part, the size reduction of a product can be expected. 
         [0043]    According to a 3-dimension range finder sensor of one embodiment of the present invention, a vertical drive system shifting a mirror assembly in a vertical direction is disposed at the outer side of a cylindrical body supporting the mirror assembly separately from a horizontal drive system. Therefore, the run-out of a product may be reduced, and the reduction of product height is possible. 
         [0044]    Also, according to a 3-dimension range finder sensor of one embodiment of the present invention, a vertical movement body for moving a mirror assembly in a vertical direction may be supported by a guide axis extended to the vertical direction, thereby performing a vertical movement safely. 
         [0045]    The embodiment of the present invention described in the foregoing part and shown in the drawings should not be understood in a sense of limiting the technical spirit of the present invention. The scope of the present invention is only restricted to substance stated in the claims, and those skilled in the art may improve and change the technical spirit of the present invention in various forms. Therefore, such improvements and changes would fall in the scope of the present invention as long as they are obvious to those skilled in the art.