FR 3100221 A1 20210305 FR 2008273 A 20200804 Description Title of Invention: electric vehicle Technical Field [0001] This disclosure relates to an clectric vehicle including a mobile hase configurcd to be capable of traveling hy an clectromotive drive, a scat having a scating portion, and a back plate configured to be usablc as a backrest corresponding to the scating portion Background Art [0002] As means of transportation for users, such as the elderly, people in need of care, and/ or the like, an electric vehicle, such as an electric-powered wheelchair, an electricpowered cati, or thelike that can travel hy driving mcans, such as a motor or the like, is hecoming popular. The clectric vehicle as ahove may bc callcd a "mobility scooter". The clectric vehicle typically includcs a mobile base configurcd to bc capable of traveling hy an clectromotive drive, a scat having a scating portion, and a back plate configured to bc usablc as a backrest corresponding to the scating portion, and the user can movc in a state of sitting on the scating portion of the scat of the clectric vehicle and also leaning on the back plate. [0003] The electric vchicic may be configured to bc foldahle. Spccifically, the clectric vehicle may bc configurcd to bc changeable between: an unfolded state in which the mobile base is expanded in the front-rcar direction such that the user can he in a riding state and stahility at the timc of travel can bc ohtained; and a folded state in which the mobile base is contractcd in the front-rcar direction so as to he suitable for tnovement causcd hy pushing the electric vehicle from the rear side of the electric vchicic hy hand. The clectric vehicle as ahove is required to he movcahle hy the pushing with hand while baggage is loaded thercon, particularly, in the folded state. Thereforc, various structures for loading baggage in the clectric N'aide have heen proposed. [0004] An clectric vehicle having the structure for loading the baggagc, cited as one example of the ahove clectric vehicles, includes: a vchicic body having a front wheel and a rcar wheel and configurcd so as to be capable of expanding and contract a wheelbase; a scat having a scating portion and arranged on the vehicle body; a backrest positioned on the rear side of the sent and formed in an inverted U-shape in front view; a basket permanently installed so as to be capable of receiving baggage and formed to be opened upwai-d in a U-shape in cross section; and one steering wheel that is configured so as to operate the electric vehicle and stay in a fixed position. In the electric vehicle, the seating portion is arranged such that the user can operate one steering wheel when the user is in a state of sitting on the seating portion of the scat, the backrest is arranged so as to rise from the rear side of the seating portion, and the 2 basket is arranged close to the lower side of the vehicle body in the unfolded state of the electric vehicle, and the seating portion and the basket are arranged to be on the upper side with respect to the positions in the unfolded state and the backrest is laid down on the seating portion in the folded state of the electric vehicle (for example, see JP 2016-168153 A). [0005] However, in the one example of the electric vehicle described abovc, the basket for receiving the baggage is permanently installed, and the installation space for the basket as abovc upsizes the electric vehicle. In particular, from the viewpoint of improving the sharp-turn performance of the clectric vehicle, the upsizing of the electric vehicle is a prohlcm. When the basket is downsized by taking the downsizing of the clectric vehicle into considération, the receiving space for the baggage cannot be sufficicntly secured. In this case, in particular, it becomes difficult to stably load a shopping basket with rigidity, which is placed in a supermarket, a shopping center, or the like, on the electric vchicic, and it hccomes difficult to stably transport the shopping basket hy the electric vchicic. [0006] -In one example of the clectric vehicle described alunie, a usage in which the clectric vehicle is moved hy pushing the electric vchicic hy hand whilc baggage, such as the shopping basket or the like is loaded on the seating portion of the clectric vehicle in the unfolded state, is conceived. However, the baggage on the scating portion cannot be stably hcld and the baggage cannot be stably transported, depcnding on the clectric vehicle in the unfolded state. There is a problem in that the electric vehicle in the unfolded state is large in size, and there is a problem that it is difficult for the electric vehicle in the unfolded state to make sharp turns. On the whole, it is also important to improve the convenience of the electric vehicle. [0007] Accordingly, in the electric vehicle, it is desired that the electric vehicle can be downsized, and that the baggage can be stably loaded and transported. In the electric vehicle, it is desired that the convenience can be irnproved.). Summary [0008] To solve the problcms as described above, an clectric vehicle according to one aspect includes: a mobile base configured to be capable of traveling hy an electromotive drive; a sent arranged on the mobile base and including a seating portion having a sitting surface; and a back plate arranged on the mobile base and configured to be usable as a backrest conesponding to the seating portion, the mobile base includes: a front base having a front wheel; and a rear base arranged doser to a rear of the vehicle than to the front base and having a rear wheel, the front and rear bases are configured to be moveable relative to each other such that the mobile base is changeable between an expanded state in which a wheelbase between the front wheel and the rear wheel is 3 expanded, and a contracted state in which the wheelhase is more contracted than in the expanded state, the scat is configurcd to be moveable between a sitting position in which the sitting surface is arrangcd so as to he directed to an upper of the vehicle, and a retracted position in which the scating portion is retractcd from the sitting position to a vehicle front sidc, the scat is configurcd so as to be arrangeable in the sitting position in the cxpandcd state and is arrangeable in the retracted position in the contracted state, the back plate is configurcd to be moveable between a raiscd position doser to the rcar of the vehicle and the upper of the vehicle than to the scating portion in the sitting position, and a laid down position doser a front of the vehicle than the raised position, the back plate is arrangeable in die raised position in a state in which the scat is arrangcd in the sitting position, and is arrangeable in the laid down position in a state in which the scat is arrangcd in the retracted position, the mobile hase includes a cargo hcd portion configurcd such that baggage is loadable therein from the upper of the vehicle, the cargo hcd portion is positioned doser to the lower of the vehicle than to the scating portion of the scat in the sitting position, and is positioned doser to the rcar of the vehicle than to the seating portion of the scat in the retractcd position, and the back plate has a through hole formed so as to face at least a part of the cargo hcd portion in a vehicle upper-lower direction in a state in which the back plate is in the laid down position. [0009] -In the electric vehicle according to one aspect, the clectric N'aide can he downsizcd, the user can stably ride the electric vehicle, and the baggage can be stably loaded and transported. In the electric vehicle, the convenience can be improved [0010] The following features, can be optionally implemented, separately or in combination one with the others. [0011] The electric vehicle further comprises a battery configured to be capable of supplying electric power used in the electromotive drive, wherein the seating portion of the seat includes a receiving portion capable of receiving the battery and arranged doser to the lower of the vehicle than to the sitting surface, the receiving portion has an opening formed in a rear-end portion of the seating portion in a seat front-rear direction such that the battery is receivable in the receiving portion and removeable from the receiving portion, and the through hole in the back plate is fonned so as to correspond to the opening in the receiving portion of the seat in the retracted position and be capable of passing the battery through the through hole in a state in which the back plate is in the laid down position. [0012] The electric vehicle further comprises a lock apparatus configured to be capable of locking a relative movement of the front and rear bases at least hi the contracted state of the mobile base, wherein the lock apparatus includes a switch configured to be capable of switching a locked state and an unlocked state of the lock apparatus, the switch is arranged on a rear end portion of the seating portion of the seat, and the through hole in the back plate is further formed so as to correspond to the switch and be capable of visually recognizing the switch through the through hole in the back plate in a state in which the seat is in the retracted position and the back plate is in the laid down position. [0013] The lock apparatus includes a display unit capable of separately displaying locking and unlocking of the lock apparatus, the display unit is arranged on the rear end portion of the scating portion of the scat, and the through hole in the back plate is further formed so as to correspond to the display unit and be capable of visually recognizing the display unit through the through holc in the back plate in a state in which the scat is in the retracted position and the back plate is in the laid down position. Brief Description of Drawings [0014] Other fcatures, dctails and advantagcs will be shown in the following detailed de- scription and on the figures, on which: Fig. 1 100151 Wei l is a front perspective view schematically showing an electric vehicle according to an Embodiment in an unfolded state. Fig. 2 100161 I fie.21 is a side view schematically showing the electric vehicle according to the Em- bodiment in the unfolded state in a partially cross-sectional view. Fig. 3 100171 Ifig.31 is a front perspective view schematically showing the electric vehicle according to the Embodiment in a folded state. Fig. 4 [0018] [fig.4] is a side view schematically showing the electric vehicle according to the Em- bodiment in the folded state in a partially cross-sectional view. Fig. 5 [0019] [fig.5] is a schematic vicw of a lock switch in an OFF state, positioncd on a rear end of a scating portion of a scat, sem from a through hole in a back plate in the foldcd state of the clectric vehicle according to the Embodiment. Fig. 6 [0020] [fig.6] is a schematic vicw of the lock switch in an ON state, positioncd on the rear end of the scating portion of the scat, sccn from the through hole in the back plate in the folded state of the electric vehicle according to the Embodiment. Fig. 7 100211 Ifig.71 is a perspective view schematically showing the electric vehicle according to the Embodiment in the folded state and a state in which a golf bag is loaded. Description of Embodiments [0022] An electric vehicle according to an Embodiment will be desciibed below. The electric vehicle according to this Embodiment is a single-seater vehicle, and the electric vehicle is configured such that a seat installed thereon is opened to the outside of the electric vehicle. For example, the electric vehicle may be an electric-powered wheelchair, an electric-powered cari, or the like, and the electric vehicle particularly may be a single-seater electric-powered wheelchair, a single-seater electric-powered cari, or the like. However, the electric vehicle is not limited to those configurations. The electric vehicle is simply called a "vehicle" below, as necessary. [0023] In the drawings used to explain this Embodiment, directions defined based on the vehicle, are indicated as follows. In other words, the vehicle front side and the vehicle rear side are indicated hy a single-headed arrow F and a single-headed arrow R respectively. Therefore, the vehicle front-rear direction is indicated hy the single-headed arrow F and the single-headed arrow R. The vehicle width direction is indicated hy a double-headed arrow W. The vehicle upper side and the vehicle lower side are indicated hy a single-headed arrow U and a single-headed arrow L respectively. Therefore, the vehicle upper-lower direction is indicated hy the single-headed arrow U and the single-headed arrow L. 100241 "Outline of Electric vehicle" 100251 The outline of the electric vehicle according to an Embodiment will he descrihed. As shown in Figures 1 to 4, the vehicle includes a mobile hase 10 configured to he capable of traveling hy an electromotive drive. The vehicle includes one seat 20 arranged on the mobile hase 10. The seat 20 includes a seating portion 22 having a sitting surface 21 configured such that the user can sit thereon. In particular, the seat 20 may he for one person. However, the seat of the vehicle is not limited to the ahove. 100261 Directions with respect to the seat 20 are defined as follows. The sitting surface 21 side of the seat 20 is defined as a "seat upper side". The side opposite to the sitting surface 21 of the seat 20, that is to say, the side opposite to the "seat upper side" is defined as the "scat lower side". A "seat upper-lower direction" is defined based on the "seat upper side" and the "seat lower side". The front surface side of the seating portion 22 of the seat 20 is defined as a "seat front side". The rear surface side of the seating portion 22 of the scat 20, that is to say, thc sicle opposite to the "scat front skie" is dcfincd as a "scat rcar sicle". A "scat front-rcar direction" is dcfincd bascd on the "scat 6 front sidc" and the "scat rcar sidc". The direction orthogonal to the "scat upper-lower direction" and the "scat front-rcar direction" is dcfincd as a "scat width direction". The "scat width direction" substantially may match with the vehicle width direction. [0027] The vehicle includcs a hack plate 30 configured to he usablc as a backrest cont- sponding to the scating portion 22. The hack plate 30 is arranged on the mobile hase 10. [0028] The mobile hase 10 includcs two front wheels 11, and two rcar wheels 12 positioned so as to he spaccd apart from thosc front wheels 11 to the vehicle rcar sidc. The front wheels 11 and the rcar wheels 12 arc traveling wheels of the vehicle. However, the mobile hase only needs to include at least one front wheel and two or more rcar wheels, or includc two or more front wheels and at least one rcar wheel. [0029] The mobile hase 10 includcs a front hase 13 having the front wheels 11 and a rcar hase 14 having the rcar wheels 12. The rcar hase 14 is arranged on the vehicle rcar side with respect to the front hase 13. The front and rcar hases 13 and 14 arc configurcd to be moveable relative to cach other so as to he changeable between the expanded state and the contracted state of the mobile hase 10. As shown in Figures 1 and 2, the expandcd state of the mobile base 10 is a state in which a wheelbase H between the front wheels 11 and the rcar wheels 12 of the mobile hase 10 is expanded. As shown in Figures 3 and 4, the contracted state of the mobile hase 10 is a state in which the wheelbase H is more contracted than in the expanded state. [0030] As shown in Figures 1 to 4, the seat 20 is configured to be moveable between a sitting position and a retracted position. As shown in Figures 1 and 2, the sitting position of the scat 20 is a position in which the seat 20 is arranged such that the sitting surface 21 faces the vehicle upper side. The seat 20 can be arranged in the sitting position in the expanded state of the mobile base 10. As shown in Figures 3 and 4, the retracted position of the seat 20 is a position in which the seat 20 is arranged such that the seating portion 22 is retracted from the sitting position to the vehicle front side. The seat 20 can be arranged in the retracted position in the contracted state of the mobile base 10. [0031] As shown in Figures 1 to 4, the back plate 30 is configured to be moveable between a raised position and a laid clown position. As shown in Figures 1 and 2, the raised position of the back plate 30 is a position in which the back plate 30 is arranged on the vehicle rear side and the vehicle upper side with respect to the seating portion 22 in the sitting position. The back plate 30 can be arranged in the raised position in a state in which the scat 20 is arranged in the sitting position. As shown in Figures 3 and 4, the laid down position of the back plate 30 is a position in which the back plate 30 is laid down to the vehicle fi-ont side with respect to the raised position. The back plate 30 can be arranged in the laid down position in a state in which the seat 20 is arranged in the 7 retracted position. [0032] As shown in Figures 1 to 4, the mobile hase 10 includes a cargo hed portion 15 configured such that baggage is loadable thercin from the vehicle upper ride. The cargo lied portion 15 is positioncd on the vchicic lower side with respect to the scating portion 22 of the scat 20 in the sitting position. The cargo bcd portion 15 is positioncd on the vehicle rcar side with respect to the scating portion 22 of the scat 20 in the retracted position. The back plate 30 has a through hole 31 formed so as to face at least a part of the cargo bed portion 15 in the vehicle upper-lower direction in a state in which the back plate 30 is in the laid down position. [0033] The electric vehicle according to this Embodimcnt may he schcmatically configured as follows. As shown in Figures 1 to 4, the vehicle includes a battery 40 configured to he capable of supplying electric power used in the clectromotive drive. The scating portion 22 of the scat 20 includes a recciving portion 50 configured so as to he capable of receiving the battery 40. The receiving portion 50 is arranged on the scat lower side with respect to the sitting surface 21 of the scat 20. [0034] The receiving portion 50 has an opcning 51 formcd such that the battcry 40 is reccivahle in the receiving portion 50 and the battcry 40 is removable from the receiving portion 50. The opcning 51 is provided in a rcar-end portion of the seating portion 22 in the scat front-rcar direction. The through hole 31 in the kick plate 30 is forrncd so as to correspond to the opcning 51 in the recciving portion 50 of the scating portion 22 in the scat 20 and be capable of passing the battery 40 therethrough in a state in which the seat 20 is in the retracted position and the back plate 30 is in the laid down position. [0035] As shown in Figures 1 to 6, the vehicle includes a lock apparatus 60 configured to be capable of locking the relative movement of the front and rear bases 13 and 14 at least in the contracted state of the mobile base 10. As shown in Figures 2 to 5, the lock apparatus 60 includes a switch 61 configured to be capable of switching the lock apparatus 60 between a locked state and an unlocked state. The switch 61 is arranged in the rear-end portion of the seating portion 22 of the seat 20. As shown in Figures 5 and 6, the through hole 31 in the back plate 30 is further fonned so as to correspond to the switch 61 and be capable of visually recognizing the switch 61 through the through hole 31 in the back plate 30 in a state in which the seat 20 is in the retracted position and the back plate 30 is in the laid down position. [0036] As shown in Figures 1 to 6, the lock apparatus 60 includes a display unit 62 that can separately display the locked state and the unlocked state of the lock apparatus 60. The display unit 62 is arranged on the rear-end portion of the seating portion 22 of the seat 20. As shown in Figures 5 and 6, the through hole 31 in the back plate 30 is further formed so as to correspond to the display unit 62 and be capable of visually recognizing the display unit 62 through the through hole 31 in the back plate 30 in a state 8 in which the scat 20 is in the retracted position and the back plate 30 is in the laid down position. [0037] "Details of Mobile Base" [0038] In detail, the mobile hase 10 may be configurcd as follows. As shown in Figures 1 to 4, in the mobile hase 10, to expand and contract the wheelbase H, the rcar wheels 12 arc drivcn and the front wheels 11 arc stopped. In other words, when the wheelbase H is expanded, the rcar wheels 12 arc rotatahly driven so as to movc the rcar hase 14 to the vehicle rcar ride, and the front wheels 11 arc stopped so as to keep the front hase 13 at a fixed position. When the wheelbase H is contracted, the rear wheels 12 arc rotatahly drivcn so as to move the rcar hase 14 to the vehicle front side, and the front wheels 11 arc stopped so as to keep the front hase 13 at a fixed position. [0039] However, the mobile hase may be configured so as to drive the front wheels and stop the rcar wheels in order to expand and contract the wheelbase. The mobile hase may he configured such that the front wheels and the rcar wheels arc driven in an inverted manncr with respect to cach other in ordcr to cxpand and contract the wheelbase. [0040] The front and rear bases 13 and 14 of the mobile hase 10 can suhstantially slide lincarly relative to cach other in the vehicle front-rcar direction. In an overlapping region between the front and rcar hases 13 and 14, the front hase 13 can he positioned on the N'aide lower side with respect to the rcar hase 14. When the front and rcar hases 13 and 14 move relative to cach other, the front hase 13 can pass through the inner portion of the rear base 14 in a base overlapping region 10a. [0041] The difference in the length of the wheelbase H between the expanded state and the contracted state of the mobile base 10 may be equal to or greater than a half of the maximum length of the scat 20 in the seat front-rear direction and equal to or less than the same maximum length. The vehicle can stably travel while stably supporting the user that is riding when the mobile base 10 is in the expanded state, and the vehicle can be compact ami make sham tums when the mobile base 10 is in the contracted state. [0042] The front base 13 of the mobile base 10 includes two front side members 13a arranged so as to be spaced apart from each other in the vehicle width direction. The two front wheels 11 are attached to front-end portions of the two fi-ont side members 13a in the vehicle front-rear direction so as to be rotatable about a rotation axis 1 la extending in the vehicle width direction. [0043] Each of the front side members 13a includes a tuming shaft 16 formed so as to protrude to the vehicle width direction from a rear-end portion of the front side member 13a in the vehicle front-rear direction. Although details are desciibed below, leg portions 23 of the seat 20 are attached to the tuming shafts 16 respectively. The tuming shafts 16 are arranged so as to avoid interference with the rear base 14 when the fi-ont and rear bases 13 and 14 move relative to each other. 9 [0044] As shown in Figure 1, the turning shafts 16 may bc positioned in front-end portions of rcar side rnembers 14a descrihed next in the vchicic front-rcar direction in the cxpanded state of the mobile hase 10. As shown in Figure 3, the turning shafts 16 may be respectively positioned ncar the rcar wheels 12 in the contracted state of the mobile hase 10. [0045] As shown in Figures 1 and 3, the rcar hase 14 of the mobile hase 10 includes the two rcar sicle membcrs 14a arranged to he spaced apart from cach other in the vehicle width direction. The two rcar whecls 12 arc attached to rcar-end portions of the two rcar sidc mcmbers 14a in the vehicle front-rcar direction respectively so as to be rotatablc about a rotation axis 12a extcnding in the vehicle width direction. [0046] Although not particularly shown in a clear rnanner, a braking apparatus configured so as to be capable of hraking the two front wheels 11 is mounted in the front hase 13 of the mobile hase 10. Driving motors for rotatahly driving the rcar wheels 12, respectively, arc mounted on the rcar hase 14 of the mobile hase 10. For example, the driving motors arc arranged so as to he adjacent to the rcar wheels 12 in the vehicle width direction, respectively, or the driving motors arc built in the rcar wheels 12, respectively. However, the driving motors are not limited thercto. [0047] -In the vchicic as above, the hraking apparatus, a control apparatus, and the driving motors arc clectrically connected to the hattcry 40. The hattcry 40 can supply clectric power to the hraking apparatus, the control apparatus, and the driving motors. The control apparatus is connected to the braking apparatus and the driving motors. The control apparatus can control the battery 40 and the driving motors. [0048] "Details of Cargo Bed Portion" [0049] In detail, the cargo bed portion 15 provided on the mobile base 10, may be configured as follows. As shown in Figures 1 to 4, the cargo bed portion 15 is arranged on the rear base 14 of the mobile base 10. The cargo bed portion 15 has a loading surface 15a arranged along the horizontal direction of the vehicle. As shown in Figure 3, the through hole 31 in the back plate 30 is fonned so as to face at least a part of the loading surface 15a in the vehicle upper-lower direction in a state in which the back plate 30 is in the laid clown position. [0050] The cargo bed portion 15 has peripheral walls 15b protruding to the vehicle upper sicle from outer peripheral edges of the loading surface 15a. By the peripheral walls 15b, the baggage loaded on the loading surface 15a of the cargo bed portion 15, can be prevented from falling from the vehicle when the vehicle moves, for example. [0051] "Details of Seat" [0052] In detail, the seat 20 may be configured as follows. As shown in Figures 1 to 4, the seat 20 further includes the two leg portions 23 that support the seating portion 22. The two leg portions 23 are arranged so as to be spaced apart from each other in the seat width direction. However, the scat may be configurcd so as to include at lcast one leg portion. [0053] -In the scat 20, the scating portion 22 [-noves to the vehicle front side hy the movement of the Icg portions 23 in accordance with the relative movement of the front and rcar hases 13 and 14 in the vehicle front-rear direction for contracting the wheelbase H. The scating portion 22 movcs to the vehicle rcar side hy the movement of the leg portions 23 in accordance with the relative movement of the front and rcar hases 13 and 14 in the vehicle front-rcar direction for expanding the whcclbase H. [0054] As shown in Figures 1 and 2, the scating portion 22 is arrangcd in the sitting position in the cxpanded state of the mobile hase 10. The scat 20 may be arrangcd such that the sitting surface 21 of the seating portion 22 is substantially along the vehicle horizontal direction in a statu in which the scat 20 is in die sitting position. As shown in Figures 3 and 4, die scat 20 is arrangcd in die retracted position in the contracted state of the mobile hase 10. The scat 20 can be arrangcd such that the sitting surface 21 of the scating portion 22 faces a plane extending in the vchicic upper-lower direction and the vchicic width direction at a predetcrmined angle in a state in which the scat 20 is in the retracted position. The absolutc value of the angle is approxirnately 30 &grecs or legs. However, the angle of the sitting surface is not limited thereto. [0055] As shown in Figures 1 to 4, a front-end zone of the seating portion 22 in the scat front-rcar direction is a free end. In a state in which the scat 20 is in the sitting position, the front-end zone of the seating portion 22 is positioned on the vehicle front sicle with respect to a rear-end zone of the seating portion 22 in the seat front-rear direction, and the rear-end zone of the seating portion 22 is positioned so as to substantially match with a [rame 70 in the vehicle front-rear direction. In a state in which the seat 20 is in the retracted position, the rear-end zone of the seating portion 22 is positioned on the vehicle upper side with respect to the front-end zone of the seating portion 22, and is positioned to be spaced apart from the frame 70 to the vehicle front side. [0056] The seat 20 includes a back-plate support mechanism 24 configured so as to support the back plate 30 in a state in which the seat 20 and the back plate 30 are in the retracted position and the laid down position respectively. The back-plate support mechanism 24 is the rear-end zone of the seating portion 22 in the seat front-rear direction. However, the present invention is not limited thereto. [0057] The kg portions 23 extend so as to incline toward the seat fi-ont sicle from the scat rear sicle as the leg portions 23 approach the seat lower sicle from the seat upper The leg portions 23 may respectively extend to the seat lower side from sicle end zones of the seating portion 22 in the seat width direction corresponding to the leg portions 23, respectively. [0058] The leg portions 23 include base attachment zones 23a configured so as to attach the 11 lcg portions 23 to thc front hase 13, respectively. Thc hase attachmcnt zones 23a arc attached to the turning shafts 16 of the front side members 13a, respectively, so as to be capable of turning. More spccifically, the hase attachmcnt zones 23a respectively have long holes 23h that arc through holes in the vehicle width direction so that the turning shafts 16 can be inserted therein, respectively. The long holes 23h extend along the longitudinal direction of the leg portions 23, respectively. When the front hase 13 [noves to thc vehicle front-rcar direction with respect to the rcar hase 14, the turning shafts 16 [-nove in the long holcs 23h along the longitudinal direction of the long holes 23b, respectively. [0059] The kg portions 23 respectively includc framc attachmcnt zones 23c configurcd such that the lcg portions 23 arc attachcd to thc framc 70 so as to be capable of turning with respect to the framc 70. Thc framc attachmcnt zones 23c arc positioncd between the scating portion 22 and thc base attachmcnt zones 23a. The hase attachmcnt zones 23a of the lcg portions 23 may be positioncd on lower ends of the lcg portions 23 in the scat upper-lower direction respectively, and the framc attachmcnt zones 23c of the leg portions 23 may be positioncd in the middle of the kg portions 23 in the scat upperlower direction, respectively. [0060] -In the scat 20 as abovc, the vehicle-front-side movement of the scating portion 22 is provided by the vehicle-rear-side movement of the hase attachmcnt zones 23a of the lcg portions 23 and the vehicle-front-side turning of the leg portions 23 in accordancc with the relative movement of the front and rear bases 13 and 14 in the vehicle frontrear direction for contracting the wheelbase H. The seating portion 22 can move to the retracted position from the sitting position by the vehicle-front-side movement. [0061] By the relative movement of the fi-ont and rear bases 13 and 14 in the vehicle front- rear direction for expanding the wheelbase H, the vehicle-front-side movement of the base attachment zones 23a of the leg portions 23 and the vehicle-rear-side turning of the leg portions 23, are provided. As a result, the vehicle-rear-side movement of the seating portion 22 is provided. The seat 20 can move to the sitting position from the retracted position by the vehicle-rear-side movement. [0062] "Details of Back Plate" [0063] In detail, the back plate 30 may be configured as follows. As shown in Figures 1 to 4, the back plate 30 is attached to the trame 70 so as to be capable of turning between the raised position and the laid down position. The back plate 30 in the laid down position is positioned on the vehicle front sicle and the vehicle lower side with respect to the back plate 30 in the raised position. As shown in Figures 1 and 2, the back plate 30 is arranged such that a front surface 32 of the back plate 30 faces the vehicle front side in a state in which the back plate 30 is in the raised position. As shown in Figures 3 and 4, the back plate 30 is arranged such that the rear surface 33 of the back plate 30 faces 12 the vehicle lower side in a state in which the back plate 30 is in the laid down position. Note that the rcar surface 33 of the back plate 30 is a surface on the side opposite to the front surface 32 of the back plate 30. [0064] As shown in Figures 1 to 4, the back plate 30 is formed in a suhstantially flat- plate-like shape. The back plate 30 has a hase-end portion 30a and a distal-end portion 30h positioned on the lower end side and the upper end side in the vehicle upper-lower direction, respectively, in a state in which back plate 30 is in the raiscd position. The hase-end portion 30a of the back plate 30 is attached to two support rods 71 of the frame 70 descrihed below such that the back plate 30 can turn about a turning axis 30e extending in the vehicle width direction. More spccifically, the hase-end portion 30a of the back plate 30 is attached to intermediate portions of the two support rods 71 in the vehicle upper-lower direction. [0065] Thc distal-cnd portion 30h of the back plate 30 is a free end. The distal-cnd portion 30h of the back plate 30 can swing about the turning axis 30e between the raiscd position and the laid down position. As shown in Figures 3 and 4, in a state in which the scat 20 is in the retracted position and the back plate 30 is in the laid down position, the distal-cnd portion 30h of the back plate 30 is supported by the back-plate support mcchanism 24 of the leg portions 23 of the scat 20. [0066] Thc through hole 31 in the back plate 30 descrihed ahove passes through the back plate 30 hetwecn the front surface 32 and the rcar surface 33 thereof. The through holc 31 is fonned so as to pass through a distal-end-side region 30e positioned on the distalend portion 30b side of the back plate 30. When the user leans on the back plate 30 in the raised position, the back of the user normally abuts a base-end-side region 30d positioned on the base-end portion 30a side of the back plate 30 and the front surface 32 of the back plate 30. Therefore, even when the through hole 31 is formed in the back plate 30, the back plate 30 can fulfill the function as the backrest. [0067] "Details of Receiving portion" [0068] In detail, the receiving portion 50 provided on the seating portion 22 of the seat 20 may be configured as follows. As shown in Figures 2 and 4, the receiving portion 50 has a cavity 52 depressed from the opening 51 toward the seat front side. The cavity 52 is fonned such that the battery 40 is receivable in the receiving portion 50 and the battery 40 is removable from the receiving portion 50 by the movement of the battery 40 in the seat front-rear direction. The cavity 52 may be fonned so as to correspond to a front-end portion 40b and an intermediate portion 40c of the battery 40 in the scat front-rear direction described below. As shown in Figures 2 and 4, the receiving portion 50 further has a connection terminal 53 that can be electrically connected to a connection terminal 41 of the battery 40. [0069] "Details of Battery" 13 [0070] -In dctail, the battery 40 may be configurcd as follows. Although not particularly shown in a clear manncr, the battcry 40 includes a rechargeable secondary oeil. As shown in Figures 2 and 4, the battery 40 has the connection terminal 41 that can bc electrically connected to the connection terminal 53 of the receiving portion 50. As shown in Figures 1 to 4, the battcry 40 is reeeived in the receiving portion 50 in a state in which a rcar-end portion 40a thercof in the scat front-rcar direction protrudes to the scat rcar sicle from the opening 51 in the receiving portion 50. The front-end portion 40h and the intermediate portion 40e of the battcry 40 in the scat front-rcar direction can he reccived in the cavity 52 of the receiving portion 50. [0071] "Dctails of Lock Apparatus" [0072] -In detail, the lock apparatus 60 may he configurcd as follows. As shown in Figures 1 and 3, the lock apparatus 60 is configurcd to be capable of locking the relative movement of the front and rear hases 13 and 14 in the expanded state of the mobile hase 10 in addition to the contracted state of the mobile hase 10. In a vehicle in which the relative movement of the front and rcar hases 13 and 14 and the movement of the scat 20 arc interlocked, the lock apparatus 60 includcs lock mcchanisms 63 that regulate the relative movement between the leg portions 23 of the scat 20 and the framc 70 fixcd on the mobile hase 10. The lock mcchanisms 63 arc provided on the framc attachment zones 23c of the log portions 23 rcspectively. Although not particularly shown in a cicar manncr, the lock mechanisms 63 arc coupled to the switch 61 by mechanical interlocking means. [0073] However, the lock mechanism may be configured so as to directly regulate the relative movement of the front and rear bases. The lock mechanisms may also be coupled to the switch by electrical interlocking means. [0074] The switch 61 of the lock apparatus 60 is moveable between an ON position for placing the lock mechanisms 63 in the locked state as shown in Figure 5 and an OFF position for placing the lock mechanisms 63 in the unlocked state as shown in Figure 6. As shown in Figures 5 and 6, when the switch 61 is moved from the OFF position to the ON position, the lock mechanisms 63 are placed in the locked state from the unlocked state by the interlocking means (not shown). When the switch 61 is moved from the ON position to the OFF position, the lock mechanisms 63 are placed in the unlocked state from the locked state by the interlocking means (not shown). In particular, when the interlocking means are mechanical, the switch 61 may be configured to be moveable in a sliding manner. However, the switch is not limited thereto. [0075] As shown in Figure 5, the display unit 62 of the lock apparatus 60 includes an ON- display zone 62a displaying that the lock apparatus 60 is, that is to say, the lock mechanisms 63 are in the locked state, and an OFF-display zone 62b displaying that 14 the lock apparatus 60 is, that is to say, the look mechanisms 63 arc in the unlocked state. In Figure 5, characters indicating "ON" arc shown in the ON-display zone 62a. In the locked state of the look apparatus 60, the ON-display zone 62a is hiddcn hy the switch 61. In Figure 6, characters indicating "OFF" arc shown in the OFF-display zone 62h. in the unlocked state of the look apparatus 60, the OFF-display zone 62h is hidden hy the switch 61. In other words, the switching hetween the ON display and the OFF display of the display unit 62 is tnechanically interlocked with the movement of the switch 61 hetween the ON position and the OFF position. [0076] However, the display unit may separately indicatc the ON display and the OFF display at a position separated from the switch. The switching hetween the ON display and the OFF display of the display unit may he clectrically interlocked with the movemcnt of the switch hetween the ON position and the OFF position. [0077] "Details of Frame" [0078] In dotai], the frame 70 may he configured as follows. As shown in Figures 1 and 2, the frame 70 is arranged so as to he adjacent to the rear-end zone of the seating portion 22 of the scat 20 in the sitting position. The frame 70 includes the two support rods 71 arranged to he spaced apart from cach othcr in the valide width direction. The two support rods 71 arc arranged so as to correspond to the two rcar side mer-libers 14a of the rcar hase 14 in the vehicle width direction, rcspectively. The two support rods 71 arc arranged so as to correspond to the two leg portions 23 of the scat 20 in the vehicle width direction, respectively. [0079] Lower end portions of the support rods 71 in the vehicle upper-lower direction are re- spectively attached to rear-end portions of the rear side members 14a in the vehicle front-rear direction corresponding to the support rods 71, respectively. The support rods 71 respectively include seat turning attachment portions 71a configured such that the frame attachment zones 23c of the leg portions 23 of the seat 20 corresponding to the support rods 71 respectively, may be attached thereto, respectively. The frame attachment zones 23c are attached to the seat turning attachment portions 71a respectively so as to be capable of turning about a turning axis 20a extending in the vehicle width direction. [0080] The seat turning attachment portions 71a are arranged on a fi-ont end and a rear end of the rear base 14 in the vehicle front-rear direction, respectively. In particular, as shown in Figures 1 and 2, the seat turning attachment portions 71a may be respectively arranged on lower-side regions of the support rods 71 in the vehicle upper-lower direction, positioned on the vehicle lower sicle with respect to die seating portion 22 of the seat 20 in the sitting position. The lower-side regions of the support rods 71 may be formed in a bending manner so as to protrude toward the vehicle front side in substantially triangular shapes. hi this case, the seat turning attachment poilions 71a may he respectively positioncd at apex portions of the lower-side rcgions protruding toward the vehicle front side in suhstantially triangular shapcs, respectively. [0081] "Unfolded State and Foldcd State of Electric vehicle" [0082] The unfolded state and the folded state of the clectric vehicle will he described. As shown in Figures 1 and 2, the vehicle is in the unfolded state when the mobile hase 10 is in the expanded state, the scat 20 is in the sitting position, and the back plate 30 is in the raiscd position. When the vehicle is in the unfoldcd state, the vehicle can travel while the user is riding the vehicle. When the vehicle is in the unfolded state, the vehicle can also travel when the user, an assistant, and/or the like pushes the vehicle hy hand whilc being on the vehicle rcar side thercof. Thc vehicle in the unfolded state may he uscd as a wheelchair, a cart, and/or the like. [0083] As shown in Figures 3 and 4, the vehicle is in the folded state when the mobile hase 10 is in the contractcd state, the scat 20 is in the retracted position, and the back plate 30 is in the laid down position as described abovc. When the vehicle is in the folded state, thc vehicle can travel when the user pushcs thc vehicle hy hand while heing on the vehicle rcar side thereof. The vehicle in the folded state may he uscd as a walking assistance vehicle, a shopping cart, a hand cart, and/or the like. [0084] "Method for Attaching and Rcmoving Battery" [0085] A method for attaching and removing the hattery 40 will he described. First, an operation for receiving the hattery 40 in thc receiving portion 50 will be described. Tn the unfolded state of the vehicle, the battery 40 can be received in the receiving portion 50 through the opening 51 while moving from the vehicle rear side toward the vehicle front side. In the folded state of the vehicle, the battery 40 can be received in the receiving portion 50 through the opening 51 atter passing through the through hole 31 in the back plate 30 while moving from the vehicle upper side toward the vehicle lower side. [0086] Next, an operation of removing the battery 40 from the receiving portion 50 will be described. In the unfolded state of the vehicle, the battery 40 can be removed from the receiving portion 50 through the opening 51 while moving ti-om the vehicle front sicle toward the vehicle rear side. In the folded state of the vehicle, the battery 40 can be removed from the receiving portion 50 through the through hole 31 in the back plate 30 after passing through the opening 51 while moving from the vehicle lower side toward the vehicle upper [0087] "Method for Operating Lock Apparatus in Folded State of Electric vehicle" [0088] A method for operating the lock apparatus 60 in the folded state of the electric vehicle will be described. In the folded state of the electric vehicle, the seat 20 is in the retracted position and the back plate 30 is in the laid down position. [0089] In the folded state of the electric vehicle as above, the lock apparatus 60 is switched 16 from the unlockcd state to the locked state as below. The user moves the switch 61 from the OFF position to the ON position hy his or her hand while putting the hand through the through hole 31 in the hack plate 30. By the movement of the switch 61, the lock mechanisms 63 can he switched from the unlocked state to the locked state, and the display unit 62 interlocked with the movement of the switch 61 is switched from the OFF display to the ON display. [0090] -In the foldcd state of the electric vehicle, the lock apparatus 60 is switched from the locked state to the unlockcd state as follows. The user moves the switch 61 from the ON position to the OFF position hy his or her hand while putting the hand through the through hole 31 in the hack plate 30. By the movement of the switch 61, the lock mechanisms 63 can Ir switched from the locked state to the unlockcd state, and the display unit 62 interlocked with the movement of the switch 61 is switched from the ON display to the OFF display. [0091] Method for Loading Baggage in Folded State of Electric vehicle" [0092] With reference to Figure 7, one example of a method for loading the baggagc on the cargo bed portion 15 in the foldcd state of the clectric vehicle will he descrihed. A case in which a golf bag G cited as one example of a long object, is loaded on the cargo bed portion 15, will he descrihed hercin. In the foldcd state of the clectric vehicle as descrihed abovc, the scat 20 is in the retracted position and the hack plate 30 is in the laid down position. [0093] In the folded state of the electric vehicle, the golf bag G is moved from the vehicle upper side toward the vehicle lower side so as to be inserted in the through hole 31 in the back plate 30. The golf bag G is placed on the loading surface 15a of the cargo bed portion 15. The golf bag G is stably loaded on the cargo bed portion 15 while being supported by the back plate 30 in a state of being inserted in the through hole 31. [0094] In the electric vehicle according to this Embodiment above, a space positioned on the vehicle lower side with respect to the seating portion 22 of the scat 20 when the electric vehicle is in the unfolded state, and a space positioned on the vehicle rear skie with respect to the seating portion 22 of the scat 20 when the electric vehicle is in the folded state are the same dead space in the electric vehicle. hi the dead space as above, the cargo bed portion 15, on which the baggage can be loaded, is arranged. Therefore, the receiving space for the baggage can be efficiently secured in the electric vehicle. As a result, the electric vehicle can be downsized. The baggage can be stably loaded on the cargo bed portion 15 as above, and the electric vehicle can stably transport the baggage in a state in which the baggage is stably loaded on the cargo bed portion 15. In particular, in the folded state of the electric vehicle, a long object, such as the golf bag G and/or the like can be loaded on the cargo bed portion 15 while being inserted in the through hole 31 in the back plate 30. In this case, the baggage can be stably loaded on 17 the cargo hcd portion 15 whilc heing supported by the back plate 30, and the clectric vehicle can stahly transport the haggage in a state in which the haggage is stahly loaded on the cargo bcd portion 15 whilc heing supported hy the back plate 30. The convenience of the clectric vehicle can he improved. [0095] -In the electric vchicic according to this Embodiment, the scating portion 22 of the scat 20 includes the receiving portion 50, which is arranged on the scat lower side with respect to the sitting surface 21 and can receive the hattery 40. The receiving portion 50 has the opcning 51 formcd in the rcar-end portion of the scating portion 22 such that the hattery 40 is receivahle in the receiving portion 50 and the hattery 40 is removable from the receiving portion 50. The through hole 31 in the back plate 30 is formcd so as to correspond to the opcning 51 in the receiving portion 50 of the seating portion 22 in the scat 20 and such that the hattery 40 is passable therethrough in a state in which the scat 20 is in the retracted position and the back plate 30 is in the laid down position. Therefore, when the electric vehicle is in the unfolded state and the user is sitting on the scat, the hattery 40 positioncd on the outside of the clectric vehicle, can Ir received in the receiving portion 50 of the scat 20 from the opcning 51 in the rear-end portion of the scating portion 22 on the rcar side of the electric vehicle. In this case, the hattery 40 received in the receiving portion 50, can he removed from the opcning 51 in the marend portion of the scating portion 22 on the rear side of the electric vehicle. When the electric vehicle is in the folded state, the hattery 40 positioned on the outside of the electric vehicle, can be received in the receiving portion 50 from the opening 51 in the rear-end portion of the seating portion 22 on the upper side of the electric vehicle. In this case, the battery 40 received in the receiving portion 50, can be removed from the opening 51 in the rear-end portion of the seating portion 22 on the upper side of the electric vehicle. Therefore, the battery 40 can be efficiently replaced in a wide variety of circumstances, and the battery 40 can be efficiently charged in a wide variety of circumstances. Therefore, the convenience of the electric vehicle can be improved. [0096] The electric vehicle according to this Embodiment includes the lock apparatus 60 formed so as to be capable of locking the relative movement of the fi-ont and rear bases 13 and 14 at least in the contracted state of the mobile base 10. The lock apparatus 60 includes the switch 61 formed to be capable of switching the locked state and the unlocked state of the lock apparatus 60. The switch 61 is arranged on the rear-end portion of the seating portion 22 of the seat 20. As shown in Figures 5 and 6, the through hole 31 in the back plate 30 is further fonned so as to correspond to the switch 61 and be capable of visually recognizing the switch 61 through the through hole 31 in the back plate 30 in a state in which the seat 20 is in the retracted position and the back plate 30 is in the laid down position. Therefore, when the baggage is loaded on the electric vehicle in which the mobile base 10 is in the contracted state, the mobile base 18 10 can be locked in the contracted state by the switch 61 without forgetting. At this time, the baggage can be stably loaded on the cargo bed portion 15 of the electric vehicle. As a result, the electric vehicle can stably transport the baggage in a state in which the mobile base 10 is reliably locked in the contracted state of the mobile base 10. Therefore, the convenience of the electric vehicle can be improved. [0097] -In the electric vehicle according ta this Embodiment, the lock apparatus 60 includcs the display unit 62 capable of separately displaying the locked state and the unlocked state of the lock apparatus 60. The display unit 62 is arranged on the rcar-end portion of the scating portion 22 of the scat 20. As shown in Figures 5 and 6, the through hale 31 in the back plate 30 is further forrned sa as to correspond ta the display unit 62 and hc capable of visually recognizing the display unit 62 through the through hale 31 in the back plate 30 in a state in which the scat 20 is in the rctractcd position and the back plate 30 is in the laid down position. Therefore, whcn the baggage is loaded on the cicctric vehicle in which the mobile hase 10 is in the contractcd state, it can lie chcckcd that the mobile hase 10 is lockcd in the contractcd state without forgctting by the display unit 62. At this time, thc haggagc can be stahly loaded on the cargo bed portion 15 of thc cicctric vchicic. As a result, the electric vchicic can stahly transport thc baggagc in a state in which thc mobile hase 10 is reliably lockcd in the contractcd state of the mobile hase 10. Therefore, thc convcnience of the cicctric vehicle can hc improved. [0098] The Embodiment of the present invention has been described above, but the present invention is not limited to the Embodiment described above, and the present invention may be modified and changed based on the technical concept thereof. Reference Signs List [0099] 10***Mobilc hase, 11***Front wheel, I2***Rear whcel, 13***Front hase, I4***Rear base, 15...Cargo bed portion, 20***Seat, 21***Sitting surface, 22***Seating portion, 30***Back plate, 31***Through hole, 40***Battery, 50***Receiving portion, 51***Opening, 60***Lock apparatus, 61...Switch, 62***Display unit, 1-1***Wheelbase 19 REVENDICATIONS[Revendications 1] An clectric vehicle comprising: a mobile base (10) configurcd to be capable of travel ing by an elcctromotive drive; a scat (20) arranged on the mobile hase (10) and including a scating portion (22) having a sitting surface (21); and a back plate (30) arranged on the mobile base (10) and configured to be usablc as a backrest corrcsponding to the scating portion (22), whercin the mobile hase (10) includcs: a front base (13) having a front wheel (11); and a rear base (14) arranged doser to a rear of the vehicle than to the front base (13) and having a rear wheel (12), the front and rear bases (13, 14) are configured to be moveable relative to each other such that the mobile base (10) is changeable between an expanded state in which a wheelbase between the front wheel and (11) the rear wheel (12) is expanded, and a contracted state in which the wheelbase is more contracted than in the expanded state, the seat (20) is configured to be moveable between a sitting position in which the sitting surface (21) is arranged so as to be directed to an upper direction of the vehicle, and a retracted position in which the seating portion (22) is retracted from the sitting position to a front of the vehicle, the seat (20) is configured so as to be arrangeable in the sitting position in the expanded state and be arrangeable in the retracted position in the contracted state, the back plate (30) is configured to be moveable between a raised position doser to the rear of the vehicle and the upper of the vehicle than the seating portion (22) in the sitting position, and a laid down position doser to the front of the vehicle than to the raised position, the back plate (30) is arrangeable in the raised position in a state in which the seat (20) is arranged in the sitting position, and is arrangeable in the laid down position in a state in which the seat (20) is arranged in the retracted position, the mobile base (10) includes a cargo bed portion (15) configured such that baggage is loadable therein from the upper direction of the vehicle, the cargo bed portion (15) is positioned doser to the lower direction of the vehicle than to the seating portion (22) of the seat (20) in the sitting position, and is positioned doser to the rear of the vehicle than to the 20 [Revendications 2] [Revendications 3] [Revendications 4] scating portion (22) of the scat (20) in the retracted position, and the back plate (30) has a through hole (31) formcd so as to face at least a part of the cargo bed portion (15) in a vehicle upper-lower direction in a state in which the hack plate (30) is in the laid down position. The clectric vehicle as clairned in daim 1, further comprising a hattery (40) configured to be capable of supplying clectric power uscd in the clectromotive drive, wherein the scating portion (22) of the scat (20) includcs a mcciving portion (50) capable of receiving the hattery (40) and arranged doser to the lower of the vehicle than to the sitting surface (21), the receiving portion (50) has an opening (51) formcd in a rear-end portion of the scating portion (22) in a scat front-rcar direction such that the hattery (40) is receivable in the receiving portion (50) and removeahle from the receiving portion (50), and the through hole (31) in the hack plate (30) is formcd so as to correspond to the opcning (51) in the receiving portion (50) of the scat in the rctracted position and be capable of passing the hattery (40) through the through holc (31) in a state in which the hack plate (30) is in the laid down position. The clectric vehicle as clairned in daim 1 or 2, further comprising a lock apparatus (60) configured to be capable of locking a relative movement of the front and rear bases at least in the contracted state of the mobile base (10), wherein the lock apparatus (60) includes a switch (61) configured to be capable of switching a locked state and an unlocked state of the lock apparatus (60), the switch (61) is arranged on a rear end portion of the seating portion (22) of the seat (20), and the through hole (31) in the back plate (30) is further fonned so as to correspond to the switch (61) and be capable of visually recognizing the switch (61) through the through hole (31) in the back plate (30) in a state in which the seat is in the retracted position and the back plate (30) is in the laid down position. The electric vehicle as claimed in daim 3, wherein the lock apparatus (60) includes a display unit (62) capable of separately displaying locking and unlocking of the lock apparatus (60), the display unit (62) is arranged on the rear end portion of the seating portion (22) of the seat (20), and 21 the through hole (31) in the hack plate (30) is further formed so as to correspond to the display unit (62) and be capable of visually reeognizing the display unit (62) through the through hole ,(31) in the hack plate (30) in a state in which the scat (20) is in the retracted position and the hack plate (30) is in the laid down position.