Patent Publication Number: US-2015075865-A1

Title: Electric Wire Holding Structure

Description:
TECHNICAL FIELD 
     The present invention relates to an electric wire holding structure in which a plurality of electric wires are press contacted to press contact terminals to be held. 
     BACKGROUND ART 
     Traditionally, an electric wire holding structure, in which a plurality of electric wires are press contacted to press contacting terminals to be held, includes an electric wire holder in which part of the plurality of electric wires are aligned and held, and an electric wire holder attached portion which is provided with the press contacting terminals to which the electric wires are press contacted, and to which the electric wire holder is attached. When the electric wire holder is attached to the electric wire holder attached portion, the plurality of electric wires are press contacted to the press contacting terminals and held in the electric wire holding structure. For example, in a PTL 1, an electric wire holding structure is disclosed which can reduce the load necessary for press contaction even if a plurality of electric wires are press contacted to press contacting terminals at the same time (for example, refer to the PTL 1). 
     The electric wire holding structure described in the PTL 1 has an electric wire holder, in which part of the plurality of electric wires are aligned and held and which has rotation shafts at one end side in a direction perpendicular to the extending direction of the plurality of electric wires, and an electric wire attached portion, which are provided with a shaft supporting portion which pivotally supports the rotation shafts and the plurality of press contacting terminals to which the electric wires are press contacted, and to which the electric wire holder is attached while the electric wire holder is pivotally supported by the shaft supporting portion and is rotated. When the electric wire holder is attached to the electric wire holder attached portion, the plurality of electric wires are press contacted to the press contacting terminals, and are held. 
     CITATION LIST 
     Patent Literature 
     
         
         PTL 1
       JP-A-2011-113802   
     
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     However, in the electric wire holding structure described in the PTL 1, because the electric wire holder is held so that the derived parts of the plurality of electric wires are kept away from the electric wire holder attached portion, the holding force of the electric wire holder becomes weak, the electric wire holder gets loose, and, as a result, the connection stability of the electric wires and the press contacting terminals might decrease. 
     The present invention is made in view of the above situation, and the object of the present invention is to provide an electric wire holding structure so that while the load necessary when a plurality of electric wires are press contacted to press contacting terminals is lowered, the connection stability of the electric wires and the press contacting terminals can be prevented from decreasing. 
     Solution to Problem 
     (1) According to an aspect of the invention, a connector connecting structure includes an electric wire holder in which part of a plurality of electric wires are aligned and held and that has a rotation shaft at one end of the electric wire holder in a direction perpendicular to an extending direction of the part of the plurality of electric wires held in the electric wire holder and an electric wire holder attached portion that includes a plurality of press contacting terminals to which the plurality of electric wires are press contacted and to which the electric wire holder is attached while the rotation shaft of the electric wire holder is supported by a shaft supporting portion and the electric wire holder is rotated. The plurality of electric wires are held by being press contacted to the press contacting terminals when the electric wire holder is attached to the electric wire holder attached portion. The electric wire holder attached portion includes a pair of electric wire holder holding walls which hold the electric wire holder by being abutted with the electric wires so that the electric wires are bent upwards at both side positions of the electric wire holder, and laterally sandwiching parts of the plurality of electric wires that are bent upwards and the electric wire holder when the electric wire holder is attached to the electric wire holder attached portion while the electric wire holder is rotated. 
     (2) In the electric wire holding structure of (1), a shape of a cross section of the rotation shaft is a semi-circular shape when the rotation shaft is cut along a plane perpendicular to a rotation axis of the rotation shaft. The shaft supporting portions have a shaft receiving groove to which the rotation shaft is insertable from above. The shaft receiving groove includes a narrow groove portion whose width is set so that the rotation shaft is insertable in a state where a straight line portion of the semi-circular sections of the rotation shaft faces an edge of the groove and a wide groove portion whose width is enlarged with respect to the width of the narrow groove portion so that a stepped face portion are horizontally formed at a lower end of the narrow groove portion and the rotation shaft is rotateable at a bottom of the shaft receiving groove so that the straight line portion face upwards. The stepped face portion is abutted with a face forming the straight line portion of the rotation shaft when the electric wire holder is moved upwards during the rotation of the rotation shaft at the bottom of the shaft receiving groove. 
     In the electric wire holding structure of (1), while the electric wire holder is pivotally supported by the shaft supporting portion and is rotated, the plurality of electric wires are press contacted to the press contacting terminals. Further, the strain relief structure is applied, the pair of electric wire holder holding walls laterally sandwich the parts of the plurality of electric wires that are bent upwards and the electric wire holder, and the electric wire holder is held so that a wobble of the electric wire holder is prevented. Therefore, while the load necessary when the plurality of electric wires are press contacted to the press contacting terminals is lowered, the connection stability of the electric wires and the press contacting terminals can be prevented from decreasing. 
     In the electric wire holding structure of (2), during the rotation of the electric wire holder, when the electric wires contact the pair of electric wire holder holding walls and the electric wire holder is moved upwards due to the reaction force, the surfaces forming the straight line portions of the rotation shafts are abutted with the stepped surfaces, and the electric wire holder is rotated while the stepped surfaces become fulcrums in the principle of leverage. Therefore, even when the electric wire holder is rotated in a state that the plurality of electric wires are located between the pair of electric wire holder holding walls, it is possible to reduce the load necessary for the rotation. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an exploded perspective view of a lighting device in which an electric wire holding structure according to an embodiment of the present invention is incorporated. 
         FIG. 2  is a perspective view of the lighting device before an electric wire holder shown in  FIG. 1  is attached. 
         FIG. 3  is an enlarged figure of an area around an electric wire holder attached portion shown in  FIG. 2 . 
         FIG. 4  is a top view of an area around the electric wire holder attached portion shown in  FIG. 3 . 
         FIG. 5  is an enlarged figure of the electric wire holder shown in  FIG. 1 . 
         FIG. 6  is a perspective view which shows a state before an upper holding portion of the electric wire holder shown in  FIG. 1  is overlaid on a lower holding portion of the electric wire holder. 
         FIG. 7  is a top view which shows a state that the electric wire holder is attached to the electric wire holder attached portion shown in  FIG. 4 . 
         FIG. 8  is a side view of the electric wire holder and the electric wire holder attached portion shown in  FIG. 7 . 
         FIG. 9  is an A-A line sectional view of the electric wire holder and the electric wire holder attached portion shown in  FIG. 7 . 
         FIG. 10  is a B-B line sectional view of the electric wire holder and the electric wire holder attached portion shown in  FIG. 7 . 
         FIGS. 11A-11C  are figures which show steps of setting four electric wires to the electric wire holder. 
         FIGS. 12A and 12B  include figures which show steps of attaching the electric wire holder to the electric wire holder attached portion. 
         FIGS. 13A and 13B  include figures which show steps of attaching the electric wire holder to the electric wire holder attached portion. 
         FIG. 14  is an A-A line sectional view of the electric wire holder and the electric wire holder attached portion shown in  FIG. 7 , and is a figure for describing a state before the electric wires are abutted with a pair of electric wire holder holding walls. 
         FIG. 15  is an A-A line sectional view of the electric wire holder and the electric wire holder attached portion shown in  FIG. 7 , and is a figure for describing a state after the electric wire holder has been attached to the electric wire holder attached portion. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Below, an embodiment of the electric wire holding structure according to the present invention is described in detail with reference to the figures. 
     Embodiment 
       FIG. 1  is an exploded perspective view of a lighting device in which an electric wire holding structure  1  according to an embodiment of the present invention is incorporated.  FIG. 2  is a perspective view of the lighting device  200  before an electric wire holder  60  shown in  FIG. 1  is attached.  FIG. 3  is an enlarged figure of an area around an electric wire holder attached portion  110  shown in  FIG. 2 .  FIG. 4  is a top view of an area around the electric wire holder attached portion  110  shown in  FIG. 3 .  FIG. 5  is an enlarged figure of the electric wire holder  60  shown in  FIG. 1 .  FIG. 6  is a perspective view which shows a state before an upper holding portion  70  of the electric wire holder  60  shown in  FIG. 1  is overlaid on a lower holding portion  80  of the electric wire holder  60 .  FIG. 7  is a top view which shows a state that the electric wire holder  60  is attached to the electric wire holder attached portion  110  shown in  FIG. 4 .  FIG. 8  is a side view of the electric wire holder  60  and the electric wire holder attached portion  110  shown in  FIG. 7 .  FIG. 9  is an A-A line sectional view of the electric wire holder  60  and the electric wire holder attached portion  110  shown in  FIG. 7 .  FIG. 10  is a B-B line sectional view of the electric wire holder  60  and the electric wire holder attached portion  110  shown in  FIG. 7 .  FIGS. 11A-11C  includes figures which show steps of setting four electric wires W to the electric wire holder  60 . 
     For convenience, the directions of arrows in the figures are assumed as forwards/backwards, right-to-left/left-to-right, and upwards/downwards directions. 
     The electric wire holding structure  1  according to the embodiment of the present invention has the electric wire holder  60  and the electric wire holder attached portion  110 . Part of the four electric wires W are aligned and held in the electric wire holder  60 , and the electric wire holder  60  has rotation shafts  72  at one end in the direction perpendicular to the extending direction of the four electric wires W. The electric wire holder attached portion  110  is provided with a plurality of press contacting terminals  32  to which the four electric wires W are press contacted, respectively. The electric wire holder  60  is attached to the electric wire holder attached portion  110  while the rotation shafts  72  of the electric wire holder  60  are pivotally supported by shaft supporting portions  120  and the electric wire holder is rotated. When the electric wire holder  60  is attached to the electric wire holder attached portion  110 , the electric wire holder  60  and the electric wire holder attached portion  110  are engaged with an engaging portion  150 , and the four electric wires W are press contacted to the press contacting terminals  32  and are held. 
     For example, such an electric wire holding structure  1  is incorporated in the lighting device  200  arranged on the indoor ceiling of a vehicle. 
     The lighting device  200  has a lens  10 , a lighting function portion  20 , and a housing  100 . 
     First, the lens  10  is described. 
     The external shape of the lens  10  is a rectangle, and the lens  10  collects light emitted from bulbs  50  which is the source of the light. 
     Next, the lighting function portion  20  is described. 
     The lighting function portion  20  has a bus bar  30 , a switch operation portion  40 , the bulbs  50  and the electric wire holder  60 . 
     The bus bar  30  is a wiring member which is made by forging a conductive metal plate-like member to a circuit shape. The bus bar  30  is attached to the housing  100  using welding pins or the like not shown in the figure. 
     The bus bar  30  has a power supply terminal  31  and four press contacting terminals  32  to which the four electric wires W are press contacted. As shown in  FIGS. 3 and 4 , each of the press contacting terminals  32  has a press contacting blade  32   a  in which a groove  32   b  is formed. When the electric wires W are pushed into the grooves  32   b  of the press contacting blades  32   a , insulative coating parts (not shown in the figure) of the electric wires W are torn off, and exposed conductor parts are connected to the press contacting blades  32   a.    
     In this embodiment, it is exemplified that the number of the electric wires W is four, but the number of the electric wires W is not limited to four. The number of the press contacting terminals  32  is also not limited, and is set according to the number of the electric wires W. 
     The switch operation portion  40  is an operation portion that changes operation modes (ON/FF) of the bulbs  50 , and is attached to the housing  100 . Contacts  41  that are terminals are incorporated in the switch operation portion  40 , and when the contacts  41  are connected to the power supply terminal  31 , an operation of supplying power to the bulbs  50  is performed in accordance with an operation mode of the switch operation portion  40 . 
     Part of the four electric wires W are aligned and held in the electric wire holder  60 , and when the electric wire holder  60  is attached to the electric wire holder attached portion  110  while being rotated, the four electric wires W are press contacted to the press contacting terminals  32  at the same time. 
     As shown in  FIGS. 5 and 6 , in the electric wire holder  60 , an upper holding portion  70  forming a holder top surface  60   a  of the electric wire holder  60  and a lower holding portion  80  forming a holder bottom surface  60   b  of the electric wire holder  60  are connected through a joint  90  which can be bent. The electric wire holder  60  is so formed that when the joint  90  is bent, the lower holding portion  80  is overlaid on the upper holding portion  70 , and the four electric wires W are sandwiched between the upper holding portion  70  and the lower holding portion  80 . 
     The upper holding portion  70  has an upper holding side engaging portion  71 , the rotation shafts  72 , and an upper holding side electric wire receiving portion  73 . 
     The upper holding side engaging portion  71  is a portion which is engaged with a lower holding side engaging portion  81  to be described below when the upper holding portion  70  is overlaid on the lower holding portion  80 . The upper holding side engaging portion  71  has an convex engaging portion  71   a  which is projected from an end  70   a  at the side where the joint  90  is not provided among the ends of the upper holding portion  70  in the direction the electric wires W are paralleled. 
     The rotation shafts  72  are projected from two side parts near the end  70   a  at the side where the joint is not provided among the ends of the upper holding portion  70  in the direction the electric wires W are paralleled. The rotation shafts  72  have a columnar shape which has a semi-circular cross section. 
     The upper holding side electric wire receiving portion  73  is a portion where the part of the four electric wires W are aligned and held, and has four electric wire receiving grooves  73   a  in which the electric wires W are embedded. 
     The lower holding portion  80  has the lower holding side engaging portion  81 , a press contacting blade penetrated portion  82 , and a lower holding side electric wire receiving portion  83 . 
     The lower holding side engaging portion  81  is a portion which is engaged with the upper holding portion side engaging portion  71  when the upper holding portion  70  is overlaid on the lower holding portion  80 . The lower holding side engaging portion  81  has an engaging strip  81   a  which has a strip form and is raised from a surface  80   b  on which the upper holding portion  70  is overlaid at the position of an end  80   a  where the joint  90  is not provided among the ends of the lower holding portion  80  in the direction the electric wires W are paralleled, and an engaging hole  81   b  which is a through hole formed in the engaging strip  81   a.    
     The press contacting blade penetrated portion  82  has through holes which are formed in the lower holding portion  80  so that the press contacting blades  32   a  can penetrate through the lower holding portion  80 . 
     The lower holding side electric wire receiving portion  83  is a portion which maintains the four electric wires W in an aligned state and pushes the electric wires W into the electric wire receiving grooves  73   a  of the upper holding portion  70  when the upper holding portion  70  is overlaid on the lower holding portion  80  so that the four electric wires W are sandwiched between the upper holding portion  70  and the lower holding portion  80 . 
     A through hole  61  for engagement, which is formed to pass through an engaging wall  126  to be described below, is formed, and when an convex engaging portion  151  which the electric wire holder  60  is provided with in the through hole  61  for engagement and an engaging hole portion  152  which the electric wire holder attached portion  110  is provided with are engaged, the electric wire holder  60  is fixed to the electric wire holder attached portion  110 . 
     When the four electric wires W are set in the electric wire holder  60 , as shown in  FIGS. 11A-11C , a jig for supporting setting electric wires  300  which fixes the electric wire holder  60  and adjusts the position and tension of each of the electric wires W is used. An operator sets the electric wire holder  60  on the jig for supporting setting electric wires  300  ( FIG. 11A ), arranges the electric wires W into the entries of the electric wire receiving grooves  73   a  of the upper holding portion  70  ( FIG. 11B ), and bends the joint  90  so that the upper holding portion  70  is overlaid on the lower holding portion  80  ( FIG. 11C ). Thereby, the four electric wires W are set in the electric wire holder  60 . 
     Next, the housing  100  is described. 
     The housing  100 , to which the lens  10  and the lighting function portion  20  are attached, is a base of the lighting device  200 . 
     The housing  100  has the electric wire holder attached portion to which the electric wire holder  60  is attached. 
     The electric wire holder attached portion  110  is a portion which is provided with four press contacting terminals  32  to which the four electric wires W are press contacted, respectively, and to which the electric wire holder  60  is attached while the rotation shafts of the electric wire holder  60  are pivotally supported by the shaft supporting portions  120  and the electric wire holder is rotated. When the electric wire holder  60  is attached to the electric wire holder attached portion  110 , the four electric wires W are press contacted to the press contacting terminals  32 , and are held. 
     The shaft supporting portion  120  has shaft receiving walls  121  including walls which are raised from an attached surface  110   a  to which the electric wire holder  60  is attached, shaft receiving grooves  122  including grooves which are formed so that the rotation shafts  72  are insertable from above, shaft falling preventing and abutting surfaces  130  against which the electric wire holder  60  abuts to regulate the upwards movement of the electric wire holder  60 , and which prevent the rotation shafts  72  from falling from the shaft receiving grooves  122 , and an engaging wall  126  which is raised from the attaching surface  110   a  to which the electric wire holder  60  is attached, and in which the engaging hole portion  152  to be described below is formed. 
     As shown in  FIG. 8 , the shaft receiving groove  121  has a narrow groove portion  123  and a wide groove portion  124  so that the width of the groove changes from a narrow part to a wide part from the entry side of the groove towards the inside of the groove. 
     The narrow groove portion  123  is a portion in which the width of the groove is about the radius of the rotation shafts which have a columnar shape whose cross section is semi-circular. With such a narrow groove portion  123 , the rotation shaft  72  is adapted to be inserted in a state where a straight line portion  72   a  of the semi-circular section shape faces the inside edge of the groove. 
     The wide groove portion  124  is a portion in which the width of the groove is enlarged until the terminal part of the groove so that a horizontal stepped surface  124   a  is formed at the lower end of the narrow groove portion  123 . With such a wide groove portion  124 , the rotation shaft  72  is adapted to be rotated at the terminal part of the groove to such a direction that the straight line portion  72   a  of the semi-circular section shape faces upwards. 
     The shaft falling preventing and abutting surface  130  has an undersurface  125   a  of an upper protruding wall  125  and the stepped surface  124   a  of the shaft receiving groove  122 . 
     The upper protruding wall  125  is a wall which is provided to be protruded above the holder top surface  60   a  of the electric wire holder  60 , and is so formed that the undersurface  125   a  of the upper protruding wall  125  is abutted with the holder top surface  60   a  when the electric wire holder  60  is moved upwards from the attached position. 
     The stepped surface  124   a  of the shaft receiving groove  122  is adapted to abut with a surface  72   b  forming the straight line portion  72   a  of the rotation shaft  72  when the electric wire holder  60  is moved upwards. 
     The electric wire holder attached portion  110  has a pair of electric wire holder holding walls  140  which hold the electric wire holder  60 . 
     The pair of electric wire holder holding walls  140  hold the electric wire holder  60  by being abutted with the electric wires W so that the electric wires W are bent upwards at two side parts  60   c  of the electric wire holder  60 , and sandwiching bended parts W 1  of the four electric wires W that are bent upwards and the electric wire holder  60  laterally, when the electric wire holder  60  is attached to the electric wire holder attached portion  110  while being rotated. 
     Each of the electric wire holder holding walls  140  has a rectangular external shape, and as shown in  FIG. 8 , the width of the electric wire holder holding walls  140  in the forwards/backwards direction is set so that the parts of the electric wires W that are hold by the electric wire holder  60  are received in the surfaces of the electric wire holder holding walls  140  when the electric wire holder  60  has been attached to the electric wire holder attached portion  110 . 
     The height of the electric wire holder holding walls  140  is set so that the upper ends of the electric wire holder holding walls  140  are located above the parts of the electric wires W that are hold by the electric wire holder  60  when the electric wire holder  60  has been attached to the electric wire holder attached portion  110 . 
     The electric wire holder holding walls  140  are set so that the distance between the electric wire holder holding walls  140  and the side parts  60   c  of the electric wire holder  60  generally equals to the diameter of the electric wires W as shown in  FIG. 10 . 
     Next, the engaging portion  150  is described. 
     With respect to the engaging portion  150 , the electric wire holder  60  and the electric wire holder attached portion  110  are engaged at the attached position of the electric wire holder  60  with the convex engaging portion  151  which the electric wire holder  60  is provided with and the engaging hole portion  152  which the electric wire holder attached portion  110  is provided with. 
     The convex engaging portion  151  is a portion which is projected from an elastic engaging strip  151   a . The elastic engaging strip  151   a  is projected into a strip shape from the hole border of the through hole  61  for engagement and the overlaid surface  70   b  of the upper holding portion  70 , and is bent into a U shape in the through hole  61  for engagement. 
     The engaging hole portion  152  is formed so that engaging wall  126  is penetrated horizontally. 
     Steps of attaching the electric wire holder  60  to the electric wire holder attached portion  110  is described by using  FIGS. 12 to 15 .  FIGS. 12A-13B  are figures which show the steps of attaching the electric wire holder  60  to the electric wire holder attached portion  110 .  FIG. 14  is an A-A line sectional view of the electric wire holder  60  and the electric wire holder attached portion  110  shown in  FIG. 7 , and is a figure for describing a state before the electric wires W are abutted against the pair of electric wire holder holding walls  140 .  FIG. 15  is an A-A line sectional view of the electric wire holder  60  and the electric wire holder attached portion  110  shown in  FIG. 7 , and is a figure for describing a state after the electric wire holder  60  has been attached to the electric wire holder attached portion  110 . 
     First, an operator attaches the rotation shafts  72  of the electric wire holder  60  to the shaft supporting portions  120  (refer to  FIG. 12A ). In this state, the electric wires W that are derived from the electric wire holder  60  are not bent, as shown in  FIG. 14 . When the rotation shafts  72  are inserted from the entries of the shaft receiving grooves  122  to be attached to the shaft supporting portions  120 , the rotation shafts  72  are inserted in a state where the straight line portions  72   a  faces the inner edges of the grooves. Therefore, the direction of the electric wire holder  60  is decided, and a false assembly of the electric wire holder  60  is prevented. 
     Then, the operator makes the electric wire holder  60  rotate around the rotation shafts  72  (refer to  FIG. 12B ). At this time, while the electric wire holder  60  is rotated, the four electric wires W are brought close to the press contacting blades  32   a . The electric wire holder  60  is rotated so that the four electric wires W derived from the two side parts  60   c  of the electric wire holder  60  start to be abutted with the pair of electric wire holder holding walls  140 , and the electric wires W are bent upwards. 
     During the rotation of the electric wire holder  60 , when the electric wires W contact the pair of electric wire holder holding walls  140 , due to a reaction force from the pair of electric wire holder holding walls  140 , the electric wire holder  60  is moved upwards, and the surfaces  72   b  of the rotation shafts  72  are abutted with the stepped surfaces  124   a . In this case, the electric wire holder  60  is rotated while the stepped surfaces  124   a  become fulcrums in the principle of leverage. 
     Then, when the operator makes the electric wire holder  60  further rotate, the electric wires W start to be press contacted to the press contacting terminals  32  (refer to  FIG. 13A ). At this time, when the electric wires W contact the press contacting blades  32   a , due to a reaction force of the force with which the electric wires W are to be cut, the electric wire holder  60  is moved upwards, and the surfaces  72   b  of the rotation shafts  72  are abutted with the stepped surfaces  124   a . Therefore, the electric wires W can be close to press contacting blades  32   a  and can be easily press contacted since the stepped surfaces  124   a  become fulcrums in the principle of leverage. 
     Then, the operator makes the electric wire holder  60  further rotate, and when the electric wire holder  60  and the electric wire holder attached portion  110  are engaged with the engaging portion  150 , the attaching of the electric wire holder  60  to the electric wire holder attached portion  110  is completed (refer to  FIG. 13B ). When the electric wire holder  60  has been attached to the electric wire holder attached portion  110 , the electric wire holder  60  is held from the sides of the two side parts  60   c  by the pair of electric wire holder holding walls  140  together with the electric wires W that are bent upwards, as shown in  FIG. 15 . Further, the electric wire holder  60  is held in a state that the electric wires W derived from the two side parts  60   c  of the electric wire holder  60  are bent upwards. That is, since the electric wires W become a strain relief structure, even if a pulling force acts on the electric wires W, the pulling force will not act directly on the press contacting points. 
     In the electric wire holding structure  1  according to the embodiment of the present invention, while the electric wire holder  60  is pivotally supported by the shaft supporting portion  120  and is rotated, the four electric wires W are press contacted to the press contacting terminals  32 . Further, the strain relief structure is applied, the pair of electric wire holder holding walls  140  laterally sandwich the parts W 1  of the four electric wires W that are bent upwards and the electric wire holder  60 , and the electric wire holder  60  is held so that a wobble of the electric wire holder  60  is prevented. Therefore, while the load necessary when the four electric wires W are press contacted to the press contacting terminals  32  is lowered, the connection stability of the electric wires W and the press contacting terminals  32  can be prevented from decreasing. 
     Further, in the electric wire holding structure  1  according to the embodiment of the present invention, during the rotation of the electric wire holder  60 , when the electric wires W contact the pair of electric wire holder holding walls  140  and the electric wire holder  60  is moved upwards due to the reaction force, the surfaces  72   b  forming the straight line portions  72   a  of the rotation shafts  72  are abutted with the stepped surfaces  124   a , and the electric wire holder  60  is rotated while the stepped surfaces  124   a  become fulcrums in the principle of leverage. Therefore, even when the electric wire holder  60  is rotated in a state that the four electric wires are located between the pair of electric wire holder holding walls  140 , it is possible to reduce the load necessary for the rotation. 
     In the electric wire holding structure  1  according to the embodiment of the present invention, it is exemplified that the electric wire holder holding walls  140  have a rectangular external shape, but the invention is not limited to this. Other shapes are also possible as long as the electric wire holder holding walls  140  are abutted with the plurality of electric wires W so that the plurality of electric wires W are bent upwards when the electric wire holder  60  is attached while being rotated, and the plurality of electric wires W and the electric wire holder  60  are laterally sandwiched when the electric wire holder  60  has been attached. 
     In the electric wire holding structure  1  according to the embodiment of the present invention, it is exemplified that the section of the rotation shafts  72  has a semi-circular shape, but the invention is not limited to this and the section may have a circular shape. 
     The invention accomplished by the inventor is described in detail based on the above embodiment of the invention, but the present invention is not limited to the above embodiment of the invention and can be modified in various ways without departing from the spirit of the invention. 
     The present application is based on Japanese Patent Application No. 2012-067130, filed on Mar. 23, 2012, the entire contents of which are incorporated herein by reference. 
     INDUSTRIAL APPLICABILITY 
     There is provided an electric wire holding structure capable of lowering a load necessary when a plurality of electric wires are press contacted to press contacting terminals and preventing the connection stability of the electric wires and the press contacting terminals from decreasing. 
     REFERENCE SIGNS LIST 
     
         
           1  electric wire holding structure 
           10  lens 
           20  lighting function portion 
           30  busbar 
           31  power supply terminal 
           32  press contact terminal 
           32   a  press contact blade 
           32   b  groove 
           40  switch operation portion 
           41  contact 
           50  bulb 
           60  electric wire holder 
           60   a  holder top surface 
           60   b  holder bottom surface 
           60   c  side parts 
           61  through hole for engagement 
           70  upper holding portion 
           70   a  end 
           70   b  overlaid surface 
           71  upper holding side engaging portion 
           71   a  convex engaging portion 
           72  rotation shaft 
           72   a  straight line portion 
           72   b  surface 
           73  upper holding side electric wire receiving portion 
           73   a  electric wire receiving grooves 
           80  lower holding portion 
           80   a  end 
           80   b  overlaid surface 
           81  lower holding side engaging portion 
           81   a  engaging strip 
           81   b  engaging hole 
           82  press contact blade penetrated portion 
           83  lower holding side electric wire receiving portion 
           90  joint 
           100  housing 
           110  electric wire holder attached portion 
           110   a  attached surface 
           120  shaft supporting portion 
           121  shaft receiving walls 
           122  shaft receiving grooves 
           123  narrow groove portion 
           124  wide groove portion 
           124   a  stepped surface 
           125  upper protruding wall 
           125   a  undersurface 
           126  engaging wall 
           130  haft falling preventing and abutting surfaces 
           140  electric wire holder holding walls 
           150  engaging portion 
           151  convex engaging portion 
           151   a  elastic engaging strip 
           152  engaging hole portion 
           200  lighting device 
           300  jig for supporting setting electric wires 
         W electric wires 
         W 1  portion bent upwards