Abstract:
A power feeding device which constitutes a contact power feeding system is provided with a pair of insulator parts which support respective suspended wires, and a bracket which includes a pair of holding plates to which the respective insulator parts are secured. The bracket is formed such that a contact surface of one suspended wire with respect to a charging arm is directed obliquely upward to a traveling road side and a contact surface of the other suspended wire with respect to the charging arm is directed obliquely downward to the traveling road side.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an electrical power supplying device (a power feeding device) and a contact type electrical power supplying system (a contact power feeding system), for supplying power in a contact manner to a pair of power receiving elements that are disposed on a charging arm that extends outwardly in a vehicle transverse direction from an electric vehicle. 
       BACKGROUND ART 
       [0002]    Conventionally, a contact type electrical power supplying system is known in which, during traveling of an electric vehicle, charging of an energy storage device of the electric vehicle is performed by bringing a pair of power receiving elements of a charging arm that extends outwardly in a vehicle transverse direction from the electric vehicle into contact with a pair of power lines of the electrical power supplying device. 
         [0003]    For example, as disclosed in Japanese Utility Model Publication No. 48-030335, a contact type electrical power supplying system has been proposed, in which a pair of upper and lower power receiving elements of a charging arm of an electric vehicle are brought into contact with a pair of power lines, by use of an electrical power supplying device equipped with a guard rail and a pair of upper and lower power lines, which are disposed in a pair of upper and lower recessed parts of the guard rail, such that flat contact surfaces thereof are oriented in a horizontal direction with respect to the power receiving elements. With such a contact type electrical power supplying system, in order to suppress positional shifting in a vertical direction (upper and lower directions) between the respective power lines and the respective power receiving elements due to unevenness of a road surface or the like, a structure is adopted in which a guide roller, which is disposed on an upper side charging arm, is placed in contact with a side surface of the upper side recessed part. 
         [0004]    Further for example, as disclosed in Japanese Laid-Open Patent Publication No. 2013-233037, a contact type electrical power supplying system has been proposed, in which a pair of power receiving elements provided on a single charging arm of an electric vehicle are brought into contact with a pair of power lines, using an electrical power supplying device, which is equipped with a power line retaining unit in which a V-shaped groove is formed that extends along a travel path of the electric vehicle and opens toward the side of the travel path, and the pair of power lines, which are fixed in respective groove side surfaces of the V-shaped groove. 
       SUMMARY OF INVENTION 
       [0005]    However, with the contact type electrical power supplying system disclosed in Japanese Utility Model Publication No. 48-030335, because there is a need to provide a guide roller on the upper side charging arm from among the pair of upper and lower charging, arms, together with forming the pair of upper and lower recessed parts in the guide rail, the charging device and the charging arms become larger in size and complex in structure. 
         [0006]    In contrast thereto, with the contact type electrical power supplying system disclosed in Japanese Laid-Open Patent Publication No. 2013-233037, since the Pair of power lines, which are fixed to the respective groove side surfaces of the V-shaped groove of the power line retaining unit, and the pair of power receiving elements provided in the single charging arm are kept in contact, positional shifting in a vertical direction of the power receiving elements with respect to the power lines can be suppressed, even without providing the aforementioned complex positional shifting suppression structure (i.e., the guide roller and the recessed parts of the guard rail, etc.). Therefore, the pair of power receiving elements can reliably be kept in contact with the pair of power lines without causing an increase in the size and complexity of the electrical power supplying device and the charging arm. However, with an electrical power supplying device of this type, because there is a need for the power line retaining unit that extends along the travel path to be constituted from an insulating material, there is a concern that a rise in manufacturing costs may occur. 
         [0007]    The present invention has been devised taking into consideration the aforementioned problems, and has the object of providing an electrical power supplying device and a contact type electrical power supplying system, in which a pair of power receiving elements can be reliably kept in contact with a pair of power lines without causing an increase in the size and complexity of the electrical power supplying device and the charging arm, together with enabling a reduction in manufacturing costs. 
         [0008]    An electrical power supplying device according to the present invention supplies power in a contact manner to a pair of power receiving elements of a charging arm that extends outwardly in a vehicle transverse direction from an electric vehicle, the electrical power supplying device comprising a pair of power lines configured to extend along a travel path of the electric vehicle in a state enabling contact with the power receiving elements, and electrical power being supplied to the power lines, a pair of insulators configured to retain the respective power lines, and a base member containing a pair of retaining plates to which the respective insulators are fixed, and being disposed on an opposite side from the travel path with respect to the pair of power lines, wherein the base member is formed to ensure an insulating distance between the pair of power lines, and to orient a contact portion of one of the power lines with respect to the charging arm in an upwardly inclined manner toward the side of the travel path, and to orient a contact portion of another of the power lines with respect to the charging arm in a downwardly inclined manner toward the side of the travel path. 
         [0009]    According to the electrical power supplying device of the present invention, because the contact portion of one of the power lines is oriented in an upwardly inclined manner toward the side of the travel path, and the contact portion of the other of the power lines is oriented in a downwardly inclined manner toward the side of the travel path, it is possible for the pair of power lines and the pair of power receiving elements to be brought into contact by entry of the charging arm between the pair of power lines. More specifically, in a state in which the pair of power lines and the pair of power receiving elements are in contact, in the case that the electric vehicle is vibrated in a vertical direction due to unevenness of the travel path, it is possible for positional shifting in the vertical direction of the power receiving elements with respect to the power lines to be suppressed, without especially providing a complex positional shifting suppression mechanism. More specifically, the pair of power receiving elements can reliably be kept in contact with the pair of power lines without causing an increase in the size and complexity of the electrical power supplying device and the charging arm. Further, due to the fact that the power lines are retained at predetermined positions while the respective power lines and the base member are insulated electrically by the insulators, since there is no need for the insulators to extend at the same length along the power lines, manufacturing costs can be reduced. 
         [0010]    In the aforementioned electrical power supplying device, a plane of one of the retaining plates may be oriented in an upwardly inclined manner toward the side of the travel path, and a plane of another of the retaining plates may be oriented in a downwardly inclined manner toward the side of the travel path. 
         [0011]    In accordance with such a configuration, with a simple structure, the contact portion of one of the power lines can be oriented in an upwardly inclined manner toward the side of the travel path, together with the contact portion of the other of the power lines being oriented in a downwardly inclined manner toward the side of the travel path. 
         [0012]    In the above-described electrical power supplying device, there may further be provided a protective member configured to isolate the pair of power lines and a space on an opposite side from the travel path with respect to the electrical power supplying device, the protective member further comprising a vertical wall positioned more on an outer side of the travel path than the pair of power lines, and configured to be extended in a vertical direction, a lower side wall configured to extend from the vertical wall downwardly of the pair of power lines, and an upper side wall configured to extend from the vertical wall upwardly of the pair of power lines. 
         [0013]    In accordance with such a structure, since the pair of power lines are isolated by the protective member from the space on the opposite side from the travel path with respect to the electrical power supplying device, safety of the road that is disposed within the space can be ensured. 
         [0014]    In the above-described electrical power supplying device, an upper surface of the upper side wall may be inclined in a downwardly inclined manner toward the outer side of the travel path. 
         [0015]    In accordance with such a configuration, rainwater that adheres to the upper surface of the upper side wall can be guided and discharged in a direction toward the road. Consequently, rusting of the power lines due to rainwater, and deterioration in the insulating capability between the respective components can be prevented. 
         [0016]    In the above-described electrical power supplying device, the protective member may include a projecting wall configured to project in at least one of upward and downward directions from an end of the upper side wall on a side of the travel path. 
         [0017]    In accordance with such a structure, since the projecting wall is provided on an end of the upper side wall on the side of the travel path, the space on the opposite side from the travel path with respect to the electrical power supplying device and the power lines can reliably be isolated from each other (contact by the hands or the like into the power line from the space can be prevented), and together therewith, infiltration of rainwater into the power lines and parts in the vicinity thereof can be suppressed. 
         [0018]    In the above-described electrical power supplying device, there may further be provided a guard rail including a support post on which the protective member is supported, and being disposed along the power lines. 
         [0019]    In accordance with this configuration, the vehicle that travels along the travel path coming into contact with the power lines can be prevented by the guard rail. Further, since the protective member is supported by the support post of the guard rail, there is no need for a member apart from the guard rail itself to support the protective member. Thus, the structure of the electrical power supplying device can further be simplified. 
         [0020]    In the above-described electrical power supplying device, there may further be provided guide members configured to guide the pair of power receiving elements of the charging arm toward the pair of power lines. 
         [0021]    In accordance with such a configuration, since the power receiving elements in a pair are guided to the pair of power lines by the guide members, the power receiving elements and the power lines can easily and reliably be brought into contact. 
         [0022]    A contact type electrical power supplying system according to the present invention is characterized by an electric vehicle including a charging arm in which a pair of power receiving elements are disposed, and which extends outwardly in a vehicle transverse direction, and an electrical power supplying device configured to supply electrical power in a contact manner to the pair of power receiving elements. 
         [0023]    In accordance with the present invention, because the contact portion of one of the power lines is oriented in an upwardly inclined manner toward the side of the travel, path, and the contact portion of the other of the power lines is oriented in a downwardly inclined manner toward the side of the travel path, it is possible for the pair of power lines and the pair of power receiving elements to be reliably brought into contact without causing an increase in the size and complexity of the electrical power supplying device and the charging arm. Further, since the respective power lines are supported in the base member through the insulators, manufacturing costs can be reduced. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0024]      FIG. 1  is a schematic plan view of a contact type electrical power supplying system according to the present invention; 
           [0025]      FIG. 2  is a front view with partial omission of an electrical power supplying device that makes up part of the electrical power supplying system; 
           [0026]      FIG. 3  is a cross-sectional view taken along line III-III of  FIG. 2 ; 
           [0027]      FIG. 4  is a cross-sectional view taken along line IV-IV of  FIG. 2 ; 
           [0028]      FIG. 5  is an enlarged cross-sectional view with partial omission of a support member that constitutes part of the electrical power supplying device; and 
           [0029]      FIG. 6  is a cross-sectional descriptive view showing a condition in which a pair of power receiving elements of an electric vehicle are placed in contact with a pair of power lines. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0030]    Below, a Preferred embodiment of a contact type electrical power supplying system, which is equipped with an electrical power supplying device according to the present invention, will be described in detail with reference to the accompanying drawings. 
         [0031]    As shown in  FIG. 1 , a contact type electrical power supplying system (contact charging system)  12  comprises an electric vehicle  14 , and an electrical power supplying device  10  that supplies power in a contact manner to the electric vehicle  14  during traveling thereof. The electric vehicle  14  is a vehicle in which there is incorporated an electric motor  16  serving as a drive source, and a driving energy storage device  18  for supplying electrical power to the electric motor  16 . The electric vehicle  14 , for example, corresponds to an electric automobile, a hybrid vehicle in which an internal combustion engine is incorporated, and a fuel cell vehicle in which a fuel cell is incorporated, or the like. 
         [0032]    Further, the electric vehicle  14  includes a charging arm  20  that extends outwardly in a vehicle transverse direction by being deployed from a side portion of one side between the from wheels WF and the rear wheels WR. In  FIG. 1 , although an example is shown in which the charging arm  20  is disposed on a left side of the electric vehicle  14 , the charging arm  20  may also be disposed on the right side of the electric vehicle  14 . The charging arm  20  includes a charging head  22  that makes up a distal end thereof. As shown in  FIG. 6 , the charging head  22  is equipped with a pair of upper and lower power receiving elements  24   p ,  24   n , which are disposed with an interval mutually therebetween. 
         [0033]    An upwardly positioned positive side power receiving element  24   p  and a downwardly positioned negative side power receiving element  24   n , respectively, are connected electrically to the energy storage device  18  of the electric vehicle  14  through a non-illustrated cable and an electric circuit. Each of the power receiving elements  24   p ,  24   n  is constituted in the form of a truncated cone, and includes a vertically directed axis of rotation. Stated otherwise, the respective power receiving elements  24   p ,  24   n  are rotatable. 
         [0034]    The electrical power supplying device  10  is disposed at a length of a specified interval on a road shoulder  201  provided on a travel path  200  of an expressway or a general road, or alternatively, on a road shoulder  201  provided on a travel path  200  of a vehicle race track, or the like. Although the length of the specified interval can be set arbitrarily, the length thereof is set to be capable of charging the electric vehicle  14 , which has a predetermined rate of electrical consumption, so as to be capable of traveling from a position of one of the electrical power supplying devices  10  to the position of a next one of the electrical power supplying devices  10 . According to the present embodiment, a walkway  202  is disposed via the road shoulder  201  on an outer side of the travel path  200  (see  FIG. 1 ). 
         [0035]    As shown in  FIGS. 2 through 4 , the electrical power supplying device  10  is equipped with a pair of upper and lower power lines  26   p ,  26   n  disposed at the length of the specified interval along the travel path  200  in a state enabling contact with the pair of power receiving elements  24   p ,  24   n , and a power source  28  that supplies electrical power to the respective power lines  26   p ,  26   n.    
         [0036]    A first voltage, which is a high DC voltage, is imposed on the upwardly positioned positive terminal side power line  26   p  from the power source  28 , and a second voltage, which is a fixed DC voltage (reference voltage) of a lower direct current than the first voltage, is imposed on the downwardly positioned negative terminal side power line  26   n  from the power source  28 . More specifically, the respective power receiving elements  24   p ,  24   n  are placed in contact with the respective power lines  26   p ,  26   n , whereby electrical power from the power source  28  is supplied to the electric vehicle  14  and is used for charging the energy storage device  18 . The power lines  26   p ,  26   n  extend roughly horizontally in a state of being separated mutually by a predetermined insulation distance. Further, the respective power lines  26 P.  26   n  are substantially rectangular shaped in cross section. 
         [0037]    The electrical power supplying device  10  is equipped with a guard rail  30  disposed along the power lines  26   p ,  26   n , a power line retaining unit  32  in which the power lines  26   p ,  26   n  in a pair are retained, a pair of upper and lower guide plates  34   a ,  34   b , and a protective member  36 . 
         [0038]    The guard rail  30  includes a wavy shaped beam  38 , which is positioned at a predetermined height from the road surface and extends at the length of the specified interval along the power lines  26   p ,  26   n , and a plurality of first support posts  40  erected on the road shoulder  201  for supporting the beam  38 . The beam  38  is fixed by fastening members  43  such as bolts or the like through respective fittings  42  to the plural first support posts  40 , which are disposed at the specified intervals along the direction of extension of the beam  38 . Further, as can be appreciated from  FIG. 3 , the beam  38  is positioned more on the side of the travel path  200  than the respective power lines  26   p ,  26   n.    
         [0039]    The power line retaining unit  32  includes a Plurality of second support posts  44  erected on the road shoulder  201 , brackets (based members)  46  disposed on each of the second support posts  44 , and a pair of lower and upper support members  48   a ,  48   b  attached to the brackets  46  and which support the respective power lines  26   p ,  26   n . The plural second support posts  44  are disposed at predetermined intervals along the travel path  200 . 
         [0040]    Each of the brackets  46  includes a base plate  50  disposed more on the side of the walkway  202  than the respective power lines  26   p ,  26   n , and which is joined to the second support post  44  and extends in the vertical direction, and a pair of retaining plates  52   a ,  52   b  provided on the base plate  50 . According to the present embodiment, the base plate  50  is joined to the second support post  44  by bolts  54 , however, it is a matter of course that the base plate  50  may be joined to the second support post  44  by any arbitrary joining method such as welding or the like. 
         [0041]    The retaining plate  52   a  extends in a downwardly inclined manner toward the side of the travel path  200  from a lower end of the base plate  50 . Stated otherwise, the plane of the retaining plate  52   a  is oriented in an upwardly inclined manner toward the side of the travel path  200 . The retaining plate  52   b  extends in an upwardly inclined manner toward the side of the travel path  200  from an upper end of the base plate  50 . Stated otherwise, the plane of the retaining plate  52   b  is oriented in a downwardly inclined manner toward the side of the travel path  200 . 
         [0042]    As shown in  FIG. 5 , the downwardly positioned support member  48   a  serves to support the power line  26   n , and includes an insulator  56  disposed on the retaining plate  52   a , a power line platform  58  attached to the insulator  56 , and a clamp  60  that fixes the power line  26   n  to the power line platform  58 . The insulator  56  comprises an insulating member  64  on which a threaded portion  62  is disposed on a base end side thereof, and a gripping tool  66  fixed to a distal end side of the insulating member  64 . The threaded portion  62  is fixed perpendicularly to the plane of the retaining plate  52   a . The insulating member  64  is constituted by a ceramic or a resin or the like having an electrical insulating property. 
         [0043]    The power line platform  58  extends at the length of the predetermined specified interval along the power line  26   n , and includes a flat-shape fixing plate  68  that is gripped by the gripping tool  66 , a pair of side plates  70 ,  72  that extend out from the fixing plate  68 , and a mounting plate  74  that contiguously adjoins the side plates  70 ,  72 . The respective side plates  70 ,  72  extend in an inclined manner so that the interval mutually therebetween narrows from the fixing plate  68  toward the mounting plate  74 , and then, extend substantially perpendicularly with respect to the fixing plate  68  to the mounting plate  74 . A base end surface of the power line  26   n  contacts the mounting plate  74 . 
         [0044]    The clamp  60  extends at the same length along the power line platform  58 , and in a state in which the distal end of the clamp  60  is engaged with a constricted portion  75  on the base end side of the power line  26   n , the base end portion of the clamp  60  is joined by bolts  76  so as to sandwich the pair of side plates  70 ,  72  therebetween. As a result, the power line  26   n  is fixed firmly with respect to the power line platform  58 . A contact surface (contact portion)  78   a  of the power line  26   n  that is fixed to the power line platform  58  with, respect to the power receiving element  24   n  is oriented in, an upwardly inclined manner toward the side of the travel path  200 . 
         [0045]    The upwardly positioned support member  48   b  has the same structure as that of the above-described support member  48   a . Therefore, detailed description of the support member  48   b  is omitted. Further, by way of the support member  48   b , a contact surface (contact portion)  78   b  of the power line  26   p  that is fixed to the power line platform  58  with respect to the power receiving element  24   p  is oriented in a downwardly inclined manner toward the side of the travel path  200 . 
         [0046]    The downwardly positioned guide plate  34   a  serves to guide the power receiving element  24   n  along the power line  26   n , and extends at the same length along the power line  26   n  in a state of being constituted by an insulating material. The guide plate  34   a  includes an attachment  80 , which is joined by the bolts  76  downwardly of the clamp  60  of the support member  48   a , and extends slightly below the contact surface  78   a  of the power line  26   n , and a guide section  82 , which is disposed on a distal end of the attachment  80 , and includes a surface  84  that is disposed substantially in parallel with the contact surface  78   a . The guide section  82  abuts against a side surface of the power line  26   n . Further, as can be appreciated from  FIG. 5 , the surface  84  of the guide section  82  is offset more toward the side of the retaining plate  52   a  than the contact surface  78   a  of the power line  26   n.    
         [0047]    The upwardly positioned guide plate  34   b  serves to guide the power receiving element  24   p  along the power line  26   p  and extends at the same length along the power line  26   p  in a state of being constituted by an insulating material. The guide plate  34   b  includes the same structure as that of the aforementioned guide plate  34   a . Therefore, detailed description of the guide plate  34   b  is omitted. Further, the attachment  80  of the guide plate  34   b  is joined upwardly of the clamp  60  of the support member  48   b.    
         [0048]    The protective member  36  serves to isolate the pair of power lines  26   p ,  26   n  from a space (a space on the side of the walkway  202 ) on the opposite side from the travel path  200  with respect to the electrical power supplying device  10 , and extends at the same length along the power lines  26   p ,  26   n . Moreover, a portion of the protective member  36  is cut out at a position corresponding to the power line retaining unit  32  (see  FIG. 3 ). This is for the purpose of avoiding interference between the protective member  36  and the power line retaining unit  32 . The protective member  36  comprises a first protective wall  86   a  provided on the side of the power line  26   n , and a second protective wall  86   b  provides on the side of the power line  26   p.    
         [0049]    The first protective wall  86   a  is constituted so as to cover the power line  26   n  downwardly thereof and from the side of the walkway  202 . More specifically, the first protective wall  86   a  includes a vertical wall  88  that extends along a vertical direction, a lower side wall  90  that extends downwardly of the power line  26   n  toward the side of the travel path  200  from a lower end of the vertical wall  88 , and an inside wall  92  that extends toward the side of the travel path  200  from an upper side portion of the vertical wall  88 . 
         [0050]    The vertical wall  88  is fixed to the first support posts  40  through a first attachment tool  94 . The lower side wall  90 , after extending substantially horizontally toward the side of the travel path  200  from the vertical wall  88 , extends upwardly in an inclined manner to a position where it does not interfere with the charging head  22  in the vicinity of the guide section  82  that constitutes the guide plate  34   a . The inside wall  92  extends substantially horizontally from the vertical wall  88  to a location slightly in front of the power line  26   n.    
         [0051]    The second protective wall  86   b  is constituted so as to cover the power lines  26   p  upwardly thereof and from the side of the walkway  202 , and includes a vertical wall  96  that extends along the vertical direction, an inside wall  98  that extends toward the side of the travel path  200  from a lower side portion of the vertical wall  96 , an upper side wall  100  that extends upwardly of the power line  26   p  toward the side of the travel path  200  from an upper end of the vertical wall  96 , and a projecting wall  102  that projects in a vertical direction from an end of the upper side wall  100  on the side of the travel path  200 . 
         [0052]    The vertical wall  96  is fixed to the first support posts  40  through a second attachment tool  104 . The inside wall  98  extends substantially horizontally from the vertical wall  96  to a location slightly in front of the power line  26   p . The upper side wall  100  extends in an upwardly inclined manner toward the side of the travel path  200  from the vertical wall  96 . The angle of inclination of the upper side wall  100  (upper surface of the upper side wall  100 ) can be set arbitrarily, however, the angle of inclination preferably is set to an angle that allows rainwater to flow toward the side of the walkway  202  due to the inclination of the upper side wall  100 , at a time that such rainwater or the like adheres to the upper surface of the upper side wall  100 . In accordance therewith, rainwater that adheres to the upper surface of the upper side wall  100  can be guided and discharged toward the side of the walkway  202 . 
         [0053]    The projecting wall  102  is positioned downwardly of the beam  38  of the guard rail  30 , and extends both upwardly and downwardly from an end of the upper side wall  100  on the side of the travel path  200 . In accordance therewith, the power lines  26   p ,  26   n  are isolated more reliably from the space on the side of the walkway  202 , and together therewith, infiltration of rainwater into the power lines  26   p ,  26   n  and parts in the vicinity thereof is further suppressed. The lower end of the projecting wall  102  is located at a position where it does not interfere with the charging head  22  in the vicinity of the guide section  82  that constitutes the guide plate  34   b.    
         [0054]    However, the projecting wall  102  may extend only upwardly, or may extend only downwardly from the end of the upper side wall  100  on the side of the travel path  200 . In either of these cases, the power lines  26   p ,  26   n  are isolated reliably from the space on the side of the walkway  202 , and together therewith, infiltration of rainwater into the power lines  26   p ,  26   n  and parts in the vicinity thereof is further suppressed. 
         [0055]    With the contact type electrical power supplying system  12  which is constituted in the foregoing manner, in the case that the energy storage device  18  of the electric vehicle  14  is to be charged, the charging arm  20  is deployed from a side portion of the electric vehicle  14  during traveling thereof, and is made to extend outwardly in the vehicle transverse direction. In addition, by bringing the electric vehicle  14  closer in proximity to the side of the power lines  26   p ,  26   n , the charging head  22  of the charging arm  20  is inserted between the pair of upper and lower guide plates  34   a ,  34   b.    
         [0056]    At this time, although the charging head  22  is vibrated vertically due to the unevenness of the travel path  200 , by the charging head  22  coming into contact with the guide plate  34   a  or the guide plate  34   b , the amplitude of vibration in the vertical direction of the charging head  22  can be minimized. In addition, when the electric vehicle  14  is made to approach closer to the side of the power lines  26   p ,  26   n , the charging head  22  is inserted between the pair of power lines  26   p ,  26   n , together with the pair of power receiving elements  24   p ,  24   n  being guided by the guide plates  34   a ,  34   b  into contact with the power lines  26   p ,  26   n.    
         [0057]    According to the present embodiment, the contact surface  78   a  of the power line  26   n  is oriented in an upwardly inclined manner toward the side of the travel path  200 , together with the contact surface  78   b  of the power line  26   p  being oriented in a downwardly inclined manner toward the side of the travel path  200 . Therefore, in a state in which the pair of power receiving elements  24   p ,  24   n  and the pair of power lines  26   p ,  26   n  are in contact, movement of the charging head  22  in the vertical direction with respect to the electrical power supplying device  10  is limited. Consequently, even if the electric vehicle  14  undergoes vibrations in the vertical direction due to unevenness of the travel path  200 , detachment of the pair of power receiving elements  24   p ,  24   n  from the pair of power lines  26   p ,  26   n  can be suppressed. 
         [0058]    When the power receiving elements  24   p ,  24   n  in a pair come into contact with the pair of power lines  26   p ,  26   n , electrical power is supplied to the energy storage device  18  from the power source  28  through the power lines  26   p ,  26   n  and the power receiving elements  24   p ,  24   n . Moreover, in such a condition, since the power lines  26   p ,  26   n  and the bracket  46  are insulated electrically by the insulators  56 , charging of the energy storage device  18  can reliably be carried out. 
         [0059]    In addition, when the electric vehicle  14  moves away from the electrical power supplying device  10 , and the power lines  26   p ,  26   n  and the power receiving elements  24   p ,  24   n  are no longer in contact, charging of the energy storage device  18  is brought to an end. After charging, the charging arm  20  is folded inward and is stored in the side portion of the electric vehicle  14 . 
         [0060]    According to the present embodiment, because the contact surface  78   a  of one of the power lines  26   n  (on the lower side) is oriented in an upwardly inclined manner toward the side of the travel path  200 , and the contact surface  78   b  of the other of the power lines  26   p  (on the upper side) is oriented in a downwardly inclined manner toward the side of the travel path  200 , it is possible for the pair of power lines  26   p ,  26   n  and the pair of power receiving elements  24   p ,  24   n  to be brought into contact by entry of the charging head  22  between the pair of power lines  26   p ,  26   n . Consequently, in a state in which the pair of power lines  26   p ,  26   n  and the pair of power receiving elements  24   p ,  24   n  are in contact, in the case that the electric vehicle  14  is vibrated in a vertical direction due to unevenness of the travel path  200 , it is possible for positional shifting in the vertical direction of the power receiving elements  24   p ,  24   n  with respect to the power lines  26   p ,  26   n  to be suppressed, without especially providing a complex positional shifting suppression mechanism. More specifically, the pair of power receiving elements  24   p ,  24   n  can reliably be kept in contact with the pair of power lines  26   p ,  26   n , without causing an increase in the size and complexity of the electrical power supplying device  10  and the charging arm  20 . 
         [0061]    Further, the insulator  56  that supports the power line  26   n  is fixed to the retaining plate  52   a  of the bracket  46 , which is disposed on the opposite side (the side of the walkway  202 ) from the travel path  200  with respect to the pair of power lines  26   p ,  26   n , and similarly, the insulator  56  that supports the power line  26   p  is fixed to the retaining plate  52   b  of the bracket  46 . Consequently, due to the fact that the respective power lines  26   p ,  26   n  are retained at predetermined positions while the respective power lines  26   p ,  26   n  and the bracket  46  are insulated electrically by the respective insulators  56 , since there is no need for the insulators  56  to extend at the same length along the power lines  26   p ,  26   n , manufacturing costs for the electrical power supplying device  10  can be reduced. 
         [0062]    According to the present embodiment, the plane of one of the retaining plates  52   a  (on the lower side) is oriented in an upwardly inclined manner toward the side of the travel path  200 , and the plane of another of the retaining plates  52   b  (on the upper side) is oriented in a downwardly inclined manner toward the side of the travel path  200 . Thus, with a simple structure, the contact surface  78   a  of the power line  26   n  can be oriented in an upwardly inclined manner toward the side of the travel path  200 , and the contact surface  78   b  of the power line  26   p  can be oriented in a downwardly inclined manner toward the side of the travel path  200 . 
         [0063]    According to the present embodiment, by the Protective member  36 , which is equipped with the first protective wall  86   a  including the vertical wall  88  and the lower side wall  90 , and the second protective wall  86   b  including the vertical wall  96  and the upper side wall  100 , the power lines  26   p ,  26   n  in a pair are isolated from the space on, the opposite side from the travel path  200  with respect to the electrical power supplying device  10 . Consequently, safety of the walkway  202  that is disposed within the space can be ensured. 
         [0064]    Further, since the upper surface of the upper side wall  100  is inclined in a downwardly inclined manner toward the side of the walkway  202 , rainwater that adheres to the upper surface of the upper side wall  100  can be guided and discharged in a direction toward the walkway  202 . Consequently, rusting of the power lines  26   p ,  26   n  due to rainwater, and deterioration in the insulating capability between the respective components (for example, between the pair of power lines  26   p ,  26   n ) can be prevented. 
         [0065]    Furthermore, since the projecting wall  102  is provided on an end of the upper side wall  100  on the side of the travel path  200 , the space on the side of the walkway  202  and the power lines  26   p ,  26   n  can reliably be isolated from each other (contact by the hands or the like into the power lines  26   p ,  26   n  from the space can be prevented), and together therewith, infiltration of rainwater into the power lines  26   p ,  26   n  and parts in the vicinity thereof can be suppressed. 
         [0066]    According to the present embodiment, since the beam  38  of the guard rail  30  is disposed more on the side of the travel path  200  than the power lines  26   p ,  26   n , a vehicle or the like that travels along the travel path  200  coming into contact with the power lines  26   p ,  26   n  can be prevented by the guard rail  30 . Further, since the protective member  36  is supported by the guard rail  30 , there is no need for a member apart from the guard rail  30  itself to support the Protective member  36 . Thus, the structure of the electrical power supplying device  10  can further be simplified. 
         [0067]    According to the present embodiment, the power receiving element  24   n  is guided to the power line  26   n  by the guide plate  34   a , and the power receiving element  24   p  is guided to the power line  26 P by the guide plate  34   b . Therefore, the power receiving elements  24   p ,  24   n  and the power lines  26   p ,  26   n  can easily and reliably be brought into contact. 
         [0068]    The present embodiment is not limited to the configuration described above. For example, the brackets  46  of the power line retaining unit  32  may also be fixed to the first support posts  40  of the guard rail  30 . In this case since the second support posts  44  of the power line retaining unit  32  are omitted, the structure of the electrical power supplying device  10  can be simplified. 
         [0069]    Further, the protective member  36  may be formed integrally with the vertical wall  88  of the first protective wall  86   a  and the vertical wall  96  of the second protective wall  86   b . In accordance therewith, the walkway  202  and the pair of power lines  26   p ,  26   n  can more reliably be isolated from each other. 
         [0070]    The electrical power supplying device and the contact type electrical power supplying system according to the present invention are not limited to the embodiments described above, and it goes without saying that various configurations may be adopted therein without deviating from the essential gist of the Present invention.