Abstract:
A pelvis assembly for a dummy includes a pelvic plate attached to a lumbar region of the dummy, and one of more pelvic units, attached to the pelvic plate to transmit motion from a femur bar of the dummy to the plate. Each pelvic unit includes a hip joint, attached to the femur bar; a rotary axle, a first end of which is attached to the hip joint, and which is disposed laterally, to rotate together with the hip joint when the femur bar pivots vertically; and one or more pelvic angle adjusters, installed near a second end of the rotary axle, to transmit rotation of the rotary axle to the pelvic plate, thereby changing a vertical angle of the pelvic plate.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to Korean Application No. 10-2007-0089904, filed on Sep. 5, 2007, the disclosure of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a pelvis assembly for a dummy used to evaluate the comfort of a vehicle seat. 
         [0004]    2. Description of the Background Art 
         [0005]    A dummy used to evaluate the comfort of a vehicle scat prototype should be able to accurately mimic various positions of human occupants. The angle of a human occupant&#39;s pelvis, for example, depends on the positioning of his/her thighs. 
       SUMMARY OF THE INVENTION 
       [0006]    A pelvis assembly for a dummy includes a pelvic plate attached to a lumbar region of the dummy, and one of more pelvic units, attached to the pelvic plate to transmit motion from a femur bar of the dummy to the plate. Each pelvic unit includes a hip joint attached to the femur bar; a rotary axle, a first end of which is attached to the hip joint and which is disposed laterally, to rotate together with the hip joint when the femur bar pivots vertically; and one or more pelvic angle adjusters, installed near a second end of the rotary axle, to transmit rotation of the rotary axle to the pelvic plate, thereby changing a vertical angle of the pelvic plate. 
         [0007]    The pelvic angle adjusters may include a seesaw lever, a core part of which is coupled near the second end of the rotary axle, and having front and rear lever parts that undergo a seesaw motion when the rotary axle rotates; and two spring members, a lower end of one being attached to the front lever part, a lower end of the other being attached to the rear lever part, and an upper end of each of which is attached to the pelvic plate. 
         [0008]    A pair of adjuster bolts may be installed on the pelvic plate so as to be able to adjust an amount of compression of the spring members. 
         [0009]    An angle sensor, which detects a rotational angle of the rotary axle, may be provided at the second end of the rotary axle. 
         [0010]    The hip joint may include a body, to which the first end of the rotary axle is fixed; and a vertical rotary spindle, which is rotatably installed on the body and attached to the femur bar. 
         [0011]    Two pelvic units may be provided at left and right sides of the pelvic plate. The vertical angle of the pelvic plate can be individually changed on a basis of movement of one of the femur bars. 
     
    
     
       BRIEF DESCRIPTION OF THE DIM WINGS 
         [0012]    The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated the accompanying drawings which are given hereinbelow by way of illustration, and thus are not limitative of the present invention, and wherein: 
           [0013]      FIGS. 1 and 2  are views illustrating the relationship between the position of a femur and the positions of the pelvis and the vertebral column in a human; 
           [0014]      FIG. 3  is a perspective view of a dummy according to an embodiment of the present invention; 
           [0015]      FIG. 4  is a perspective view illustrating the pelvis assembly indicated by part A of  FIG. 3 ; and 
           [0016]      FIG. 5  is an exploded perspective view of the pelvis assembly of  FIG. 4 . 
       
    
    
       [0017]    It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
         [0018]    In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0019]    Reference will now be made in detail to a preferred embodiment of the present invention, an example of which is illustrated in the accompanying drawings and described below. While the invention will be described in conjunction with an exemplary embodiment, it should be understood that the description is not intended to limit the invention to the exemplary embodiment. On the contrary, the invention is intended to cover not only the exemplary embodiment, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
         [0020]    As mentioned above, a dummy used to evaluate the comfort of a vehicle seat prototype should be able to accurately mimic various positions of human occupants. In particular, the skeletal or articular structure of a human being needs to be mimicked in the dummy. In this respect, it is necessary to pay attention to the fact that the position of the vertebral column is influenced by the angle of the pelvis, and furthermore, that the angle of the pelvis is influenced by the position of the thighs. 
         [0021]      FIGS. 1 and 2  show the position of the vertebral column of a seated human being. As shown in  FIG. 1 , when each femur  1  is angled below a horizontal plane extending outwards from the hip joint, the pelvis  2  is rotated forward. Thus, a vertebral column, particularly the lumbar  3 , is bent forward towards the stomach. In contrast as shown in  FIG. 2 , when the femur  1  is tilted above the horizontal plane, the pelvis  2  is rotated backward. Thus, the lumbar  3  is bent backward. In addition, the angular change of the femur  1  causes the shape of the thorax  4  to change slightly. The position of the vertebral column also has an influence on the position of the cervical vertebrae  5 . 
         [0022]    The angle of the seat exerts a direct influence on the angle of the femur. For this reason, a dummy used to evaluate the comfort of a vehicle seat prototype should have a pelvis assembly that mimics changes in the position of the vertebral column depending on the change in the angle of the femur. 
         [0023]    Referring to  FIG. 3 , a dummy is generally humanoid in shape, include limbs, a vertebral column  31 , a neck/head  32 , and a pelvis assembly A, corresponding to a human pelvic region. 
         [0024]    A posture restrictive rod  33  is connected between a shoulder girdle and a pelvic plate  20  of the dummy for restricting the change in the position of the dummy, particularly, the vertebral column  31 , within a predetermined range. When the angle of the pelvic plate  20  changes, the angle of the vertebral column  31 , particularly the lumbar region  30 , changes within a predetermined range. The angular change of the pelvic plate  20  is associated with the change in the angle of each femur bar  10 . 
         [0025]    As illustrated in  FIG. 4 , the lower end of the rod  33  is connected to the pelvic plate  20 . Although not illustrated in  FIG. 4 , the lower aid of the lumbar region  30  is also connected to the pelvic plate  20 . 
         [0026]    Referring to  FIGS. 4 and 5 , the pelvis assembly A generally comprises the pelvic plate  20  and members for transmitting changes in the position of each femur bar  10  to the pelvic plate  20 . 
         [0027]    The pelvic plate  20  is a flat, horizontal plate, and serves as a medium by which the position of the lumbar region  30  is changed depending on the movement of the femur bar  10 . 
         [0028]    The members for transmitting the positional change of each femur bar  10  to the pelvic plate  20 , for example a hip joint  40 , a rotary axle  60  and pelvic angle adjusters  70 ,  100  and  200 , are installed under the pelvic plate  20 . In some embodiments, two sets of the members are installed symmetrically on the left and right sides of the pelvic plate  20 . For simplicity, only one of the sets of members will be described below. 
         [0029]    The hip joint  40  makes it possible to move the femur bar  10  in vertical and horizontal directions. To this end, the upper end of the femur bar  10  is coupled to the hip joint  40 , and the rotary axle  60  ( FIG. 5 ) is coupled to the hip joint  40  perpendicular to the femur bar  10 . More specifically, one end of the rotary axle  60  is fixed to the body  41  of the hip joint  40 . Thus, when the femur bar  10  is pivoted in a vertical direction, the hip joint  40  rotates together with the rotary axle  60 . Further, one end of the femur bar  10  is fixed to a vertical rotary spindle  43 , which is rotatably installed on the body  41  of the hip joint  40  via a support plate  42 . Thus, the femur bar  10  can be pivoted horizontally side to side. 
         [0030]    A joint housing  50 , through which the rotary axle  60  passes, is disposed inside the hip joint  40 . A bearing  51  is interposed between the rotary axle  60  and the joint housing  50 , such that the joint housing  50  does not move, in spite of the rotation of the rotary axle  60 . This joint housing  50  functions to support the rotary axle  60 , which rotates together with the hip joint  40 . 
         [0031]    The rotary axle  60  is installed horizontally side to side, one end thereof is coupled to the hip joint  40 , and the other end thereof is coupled to a seesaw lever  70 . When the hip joint  40  rotates, the rotary axle  60  rotates therewith. This rotation of the rotary axle  60  is transmitted to the pelvic angle adjusters  70 ,  100  and  200 , including the seesaw lever  70 . 
         [0032]    The pelvic angle adjusters  70 ,  100  and  200  function to adjust the angle of the pelvic plate  20  on the basis of the rotation of the rotary axle  60 , and include the seesaw lever  70  and two spring members  100  and  200 . 
         [0033]    The seesaw lever  70  includes a core part  70   a , a front lever part  71 , which is disposed in front of the rotary axle  60 , and a rear lever part  72 , which is disposed behind the rotary axle  60 . The rotary axle  60  is fixed through the core part  70   a . When the rotary axle  60  rotates, the seesaw lever  70  undergoes a seesaw motion, which is transmitted to the spring members  100  and  200 . 
         [0034]    The spring members  100  and  200  are vertically installed on the front and rear lever parts  71  and  72  via lower end couplers  110  and  210 , respectively. The spring members  100  and  200  include housings  101  and  201 , in which springs (not shown) are installed. At upper ends of the housings  101 ,  102  are upper end couplers  120  and  220 . When the upper end couplers  120  and  220  are pressed, the springs are compressed in the housings  101  and  201 . When the upper end couplers  120  and  220  are released, the springs can be restored to original positions. 
         [0035]    Meanwhile, the upper ends of the spring members  100  and  200 , particularly the housing  101  and  201 , are fixed to the pelvic plate  20 . The pelvic plate  20  is provided with adjuster bolls  130  and  230  thereon such that the upper end couplers  120  and  220  can be compressed or released. Since one seesaw lever  70  is provided to each of the left and right femur bars  10 , a total of four adjuster bolts  130  and  230  are installed on the pelvic plate  20 , as shown in  FIG. 4 . 
         [0036]    The rotary axle  60  is exposed at the left side in  FIG. 5  of the seesaw lever  70 . The exposed rotation axle  60  is coupled with an angle sensor  90 , which is supported by a sensor holder  80 , in an axial direction. The leading end of the angle sensor  90  is coupled to the rotary axle  60 , so that the angle sensor  90  can detect the amount of rotation when the rotary axle  60  rotates. A bearing  81  is interposed between the sensor holder  80  and the rotary axle  60 . 
         [0037]    Although an exemplary embodiment of the present invention has been described for illustrative purposes, those skilled in the art wilt appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as defined in the accompanying claims.