Patent Publication Number: US-2022216771-A1

Title: Drive device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is the U.S. national stage of application No. PCT/JP2020/016430, filed on Apr. 14, 2020, and priority under 35 U.S.C. § 119(a) and 35 U.S.C. § 365(b) is claimed from Japanese Patent Application No. 2019-080351, filed on Apr. 19, 2019. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a drive device. 
     BACKGROUND 
     A drive device including a motor and rotating an axle of a vehicle is known. For example, as such a drive device, a rear transaxle that drives rear wheels is known. 
     In the drive device as described above, for example, in order to cool the motor and drive the drive device with energy efficiency, it is required to accurately detect the highest temperature among the temperatures of the motor. 
     SUMMARY 
     One aspect of a drive device of the present invention is a drive device that rotates an axle of a vehicle. The drive device includes: a motor including a rotor rotatable about a motor axis extending in a direction orthogonal to a vertical direction and a stator surrounding the rotor; a housing having a motor housing that houses the motor therein; a temperature sensor capable of detecting a temperature of the motor; and an oil passage that supplies oil to the stator from above in the vertical direction in the motor housing. The stator includes: a stator core; and a coil assembly having a plurality of coils attached to the stator core. The coil assembly includes a terminal portion located on one side of the motor axis in a predetermined direction orthogonal to both an axial direction and a vertical direction of the motor axis. The temperature sensor is provided in a portion of the coil assembly located on one side in the predetermined direction with respect to the motor axis, and is located on a lower side in the vertical direction with respect to the terminal portion and on an upper side in the vertical direction with respect to an end on a lower side in the vertical direction of the rotor. 
     The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating a schematic structure of a drive device according to the present embodiment; 
         FIG. 2  is a perspective view illustrating the drive device according to the present embodiment; 
         FIG. 3  is a cross-sectional view of a portion illustrating the drive device of the present embodiment taken along line III-III in  FIG. 2 ; 
         FIG. 4  is a perspective view illustrating a portion of the drive device according to the present embodiment; 
         FIG. 5  is a perspective view illustrating a portion of a stator of the present embodiment; 
         FIG. 6  is a perspective view illustrating a portion of a motor of the present embodiment; 
         FIG. 7  is a view of a portion of the motor of the present embodiment as viewed from the upper side; 
         FIG. 8  is a perspective view illustrating a second reservoir of the present embodiment; 
         FIG. 9  is a cross-sectional view illustrating a portion of the motor of the present embodiment taken along line IX-IX in  FIG. 7 ; 
         FIG. 10  is a cross-sectional view illustrating a portion of the motor of the present embodiment taken along line X-X in  FIG. 7 ; 
         FIG. 11  is a side view illustrating a motor of a first modification; and 
         FIG. 12  is a side view illustrating a motor of a second modification. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, the vertical direction is defined and described based on the positional relationship when a drive device  1  of an embodiment illustrated in each drawing is mounted on a vehicle located on a horizontal road surface. In addition, in the drawings, an XYZ coordinate system is illustrated appropriately as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, a Z-axis direction is the vertical direction. A+Z side corresponds to an upper side in the vertical direction, while a −Z side corresponds to a lower side in the vertical direction. In the following description, the upper side and the lower side in the vertical direction will be referred to simply as the “upper side” and the “lower side”, respectively. An X-axis direction is a direction orthogonal to the Z-axis direction and is a front-rear direction of a vehicle on which a drive device is mounted. In the embodiment below, a +X side is a front side of a vehicle, and a −X side is a rear side of the vehicle. A Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction, and is a left-right direction of the vehicle, or a vehicle lateral direction. In the embodiment below, a +Y side is a left side of a vehicle, and a −Y side is a right side of the vehicle. Each of the front-rear direction and the left-right direction is a horizontal direction perpendicular to the vertical direction. In the present embodiment, the front-rear direction corresponds to a predetermined direction. In the present embodiment, the rear side corresponds to one side in a predetermined direction, and the front side corresponds to the other side in the predetermined direction. 
     The positional relationship in the front-rear direction is not limited to the positional relationship in the embodiment below, and thus the +X side may be the rear side of a vehicle, and the −X side may be the front side of the vehicle. In this case, the +Y side is the right side of the vehicle, and the −Y side is the left side of the vehicle. 
     Each drawing appropriately illustrates a motor axis J 1  that extends in the Y-axis direction, i.e., the left-right direction of a vehicle. In the following description, unless otherwise specified, a direction parallel to the motor axis J 1  is simply referred to as an “axial direction”, a radial direction around the motor axis J 1  is simply referred to as a “radial direction”, and a circumferential direction about the motor axis J 1 , i.e., about the motor axis J 1 , is simply referred to as a “circumferential direction”. In the present specification, a “parallel direction” includes a substantially parallel direction, and an “orthogonal direction” includes a substantially orthogonal direction. 
     The drive device  1  according to the present embodiment illustrated in  FIG. 1  is installed in a vehicle having a motor as a power source, such as, for example, a hybrid electric vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV), and is used as the power source thereof. As illustrated in  FIG. 1 , the drive device  1  includes a housing  6 , an inverter unit  8 , a motor  2 , and a transmission device  3 . The transmission device  3  includes a speed reducer  4  and a differential  5 . That is, the drive device  1  includes the speed reducer  4  and the differential  5 . 
     The housing  6  includes a motor housing  81 , a gear housing  82 , and a partition  61   c . The motor housing  81  is a portion for housing a rotor  20  and a stator  30  inside described later. The gear housing  82  is a portion that houses the transmission device  3  inside. The gear housing  82  is located on the left side (+Y side) of the motor housing  81 . A bottom  81   a  of the motor housing  81  is located higher than a bottom  82   a  of the gear housing  82 . The partition  61   c  partitions the inside of the motor housing  81  and the inside of the gear housing  82  from each other in the axial direction. The partition  61   c  includes a partition opening  68 . The partition opening  68  connects the inside of the motor housing  81  and the inside of the gear housing  82 . 
     Oil O is stored in the motor housing  81  and the gear housing  82 . The gear housing  82  is provided in its inner lower region with an oil pool P in which the oil O accumulates. The oil O in the oil pool P is fed to the inside of the motor housing  81  through an oil passage  90  described later. The oil O fed to the inside of the motor housing  81  accumulates in an inner lower region of the motor housing  81 . At least some of the oil O having accumulated inside the motor housing  81  moves to the gear housing  82  through the partition opening  68  and returns to the oil pool P. 
     Note that, when an oil is herein described as being housed in a specific portion, it means that the oil is located in the specific portion at least at one time while the motor is in operation, and the oil may not be located in the specific portion when the motor is at rest. For example, in the present embodiment, “the oil O is contained inside the motor housing  81 ” means that the oil O is located inside the motor housing  81  at least partly during driving of the motor  2 . When the motor  2  is stopped, all the oil O in the motor housing  81  may move to the gear housing  82  through the partition opening  68 . In addition, some of the oil O fed to the inside of the motor housing  81  through the oil passage  90  described later may remain inside the motor housing  81  when the motor  2  is stopped. 
     The oil O is arranged to circulate through the oil passage  90 , which will be described below. The oil O is used to lubricate the speed reducer  4  and the differential  5 . In addition, the oil O is also used to cool the motor  2 . An oil equivalent to a lubricating oil for an automatic transmission (ATF: Automatic Transmission Fluid) having a relatively low viscosity is preferably used as the oil O so that the oil O can perform functions of a lubricating oil and a cooling oil. 
     The bottom  82   a  of the gear housing  82  is located below the bottom  81   a  of the motor housing  81 . This allows the oil O sent from the gear housing  82  to the motor housing  81  to easily flow into the gear housing  82  through the partition opening  68 . As illustrated in  FIG. 2 , the gear housing  82  extends in the front-rear direction. The gear housing  82  is connected at its front (+X side) end to a left (+Y side) end of the motor housing  81 . The gear housing  82  has a rear (−X side) end protruding rearward from the motor housing  81 . 
     The inverter unit  8  is located on the rear side (−X side) of the motor housing  81 . The inverter unit  8  has a substantially rectangular parallelepiped shape elongated in the axial direction. The end on the left side (+Y side) of the inverter unit  8  is located above a portion of the gear housing  82  protruding rearward from the motor housing  81 . As illustrated in  FIG. 3 , the inverter unit  8  is located on the rear side of the motor  2 . The inverter unit  8  includes an inverter case  8   a  and a control unit  8   b.    
     The inverter case  8   a  has a substantially rectangular parallelepiped box shape elongated in the axial direction. The inverter case  8   a  is attached to the rear side (−X side) of the motor housing  81  with, for example, a screw. The control unit  8   b  controls the motor  2  and an oil pump  96  to be described later. More specifically, the control unit  8   b  controls the motor  2  and the oil pump  96  based on a detection result of a temperature sensor  70  described later. The control unit  8   b  is housed inside the inverter case  8   a . The control unit  8   b  includes an inverter  8   c  that supplies power to the motor  2 . That is, the inverter unit  8  includes the inverter  8   c.    
     As illustrated in  FIG. 4 , the inverter unit  8  includes a second busbar  8   d  protruding forward from a wall portion on the front side (+X side) of the inverter case  8   a . The second busbar  8   d  penetrates the front wall portion of the inverter case  8   a  in the front-rear direction. Although not illustrated, a portion of the second busbar  8   d  located inside the inverter case  8   a  is electrically connected to the inverter  8   c . For example, three second busbars  8   d  are provided. The three second busbars  8   d  are arranged side by side at intervals in the front-rear direction. 
     In the present embodiment, the motor  2  is an inner-rotor motor. As illustrated in  FIG. 1 , the motor  2  includes a rotor  20 , a stator  30 , and bearings  26  and  27 . The rotor  20  is arranged to be capable of rotating about a motor axis J 1 , which extends in a horizontal direction orthogonal to the vertical direction. A torque of the rotor  20  is transferred to the transmission device  3 . The rotor  20  includes a shaft  21  and a rotor body  24 . Although not illustrated in the drawings, the rotor body  24  includes a rotor core, and a rotor magnet fixed to the rotor core. 
     As illustrated in  FIG. 3 , the lower end of the rotor body  24  is located above an oil level Sm of the oil O stored in the motor housing  81 . Therefore, when the rotor  20  rotates, it is possible to suppress the oil O stored inside the motor housing  81  from becoming a resistance. The lower end of the rotor body  24  is the lower end of the rotor  20 . 
     As illustrated in  FIG. 1 , the shaft  21  is arranged to extend in the axial direction with the motor axis J 1  as a center. The shaft  21  is arranged to rotate about the motor axis J 1 . The shaft  21  is a hollow shaft including a hollow portion  22  defined therein. The shaft  21  includes a communicating hole  23 . The communicating hole  23  is arranged to extend in a radial direction to connect the hollow portion  22  to a space outside of the shaft  21 . 
     The shaft  21  extends across the motor housing  81  and the gear housing  82  of the housing  6 . The end of the shaft  21  on the left side (+Y side) is arranged to protrude into the gear housing  82 . A first gear  41 , which will be described below, of the transmission device  3  is fixed to the end of the shaft  21  on the left side. The shaft  21  is rotatably supported by the bearings  26  and  27 . 
     The stator  30  is arranged radially opposite to the rotor  20  with a gap therebetween. In more detail, the stator  30  is located radially outside of the rotor  20 . The stator  30  surrounds the rotor  20 . The stator  30  includes a stator core  32  and a coil assembly  33 . The stator core  32  is fixed to an inner peripheral surface of the motor housing  81 . Referring to  FIGS. 3 and 6 , the stator core  32  includes a stator core body  32   a  and a fixing portion  32   b . Although not illustrated, the stator core body  32   a  includes a cylindrical core back extending in the axial direction, and a plurality of teeth extending radially inward from the core back. 
     The fixing portion  32   b  is arranged to protrude radially outward from an outer circumferential surface of the stator core body  32   a . The fixing portion  32   b  is a portion fixed to the motor housing  81 . As illustrated in  FIG. 6 , a plurality of the fixing portions  32   b  is provided at intervals along the circumferential direction. One of the fixing portions  32   b  is arranged to protrude upward from the stator core body  32   a . The other one of the fixing portions  32   b  is arranged to protrude rearward (i.e., the −X side) from the stator core body  32   a . The fixing portion  32   b  includes a through hole  32   c  arranged to penetrate the fixing portion  32   b  in the axial direction. The stator  30  is fixed to the housing  6  by tightening a screw passing through the through hole  32   c  into the motor housing  81 . 
     Referring to  FIG. 1 , the coil assembly  33  includes a plurality of coils  31  attached to the stator core  32  and arranged along the circumferential direction. The plurality of coils  31  is mounted on the respective teeth of the stator core  32  with corresponding insulators (not illustrated) interposed therebetween. The plurality of coils  31  is disposed along the circumferential direction. In more detail, the plurality of coils  31  is arranged at equal intervals in the circumferential direction all the way around the motor axis J 1 . Although not illustrated, in the present embodiment, the plurality of coils  31  is star-connected to form an AC circuit of a plurality of phases. The plurality of coils  31  constitutes, for example, a three-phase AC circuit. 
     The coil assembly  33  includes coil ends  33   a  and  33   b  each of which is arranged to protrude in the axial direction from the stator core  32 . The coil end  33   a  is arranged to protrude to the right side (−Y side) from the stator core  32 . The coil end  33   b  is arranged to protrude to the left side (+Y side) from the stator core  32 . The coil end  33   a  includes a portion of each of the coils  31  included in the coil assembly  33  which protrudes to the right side of the stator core  32 . The coil end  33   b  includes a portion of each of the coils  31  included in the coil assembly  33  which protrudes to the left side of the stator core  32 . In the present embodiment, the coil ends  33   a  and  33   b  constitute an annular shape about the motor axis J 1 . 
     As illustrated in  FIG. 5 , the coil assembly  33  includes coil lead wires  36 U,  36 V,  36 W,  37 U,  37 V, and  37 W, and a binding member  38 . The coil lead wires  36 U,  36 V,  36 W,  37 U,  37 V, and  37 W are drawn out from the coil  31 . In the present embodiment, the coil lead wires  36 U,  36 V,  36 W,  37 U,  37 V, and  37 W are a part of the conducting wire constituting the coil  31 . Each of the coil lead wires  36 U,  36 V,  36 W,  37 U,  37 V, and  37 W is covered with an insulating tube  39  and is wound around the coil end  33   b.    
     The coil lead wires  36 U,  36 V, and  36 W are coil lead wires electrically connected to the inverter  8   c  via a first busbar  100  and a second busbar  8   d  described later. AC currents having different phases flow from the inverter  8   c  to the coil lead wire  36 U, the coil lead wire  36 V, and the coil lead wire  36 W. A distal end of the coil lead wire  36 U is a terminal portion  34 U. A distal end of the coil lead wire  36 V is a terminal portion  34 V. A distal end of the coil lead wire  36 W is a terminal portion  34 W. That is, the coil assembly  33  has terminal portions  34 U,  34 V, and  34 W. 
     The terminal portions  34 U,  34 V, and  34 W protrude radially outward from the coil end  33   b . In the present embodiment, the terminal portions  34 U,  34 V, and  34 W protrude obliquely upward on the rear side (−X side) from the coil end  33   b . As illustrated in  FIG. 3 , the terminal portions  34 U,  34 V, and  34 W are located on the rear side (−X side) of the motor axis J 1  in the front-rear direction. The terminal portions  34 U,  34 V, and  34 W are located above the motor axis J 1 . The terminal portion  34 U, the terminal portion  34 V, and the terminal portion  34 W are arranged side by side at intervals along the circumferential direction. The terminal portion  34 U, the terminal portion  34 V, and the terminal portion  34 W are electrically connected to the inverter  8   c  via the first busbar  100  and the second busbar  8   d  described later. A crimp terminal  34   a  is provided at each of distal ends of the terminal portions  34 U,  34 V, and  34 W. The terminal portions  34 U,  34 V, and  34 W are electrically connected to the first busbar  100  via the crimp terminal  34   a.    
     As illustrated in  FIG. 5 , the coil lead wires  37 U,  37 V, and  37 W are coil lead wires whose distal ends are connected to each other via a neutral point member  37 . The neutral point member  37  electrically connects the distal end of the coil lead wire  37 U, the distal end of the coil lead wire  37 V, and the distal end of the coil lead wire  37 W as a neutral point. The coil lead wires  37 U,  37 V, and  37 W are wound along the circumferential direction on the left side (+Y side) of the portion of the coil end  33   b  located on the rear side (−X side) with respect to the motor axis J 1 . The distal ends of the coil lead wires  37 U,  37 V, and  37 W and the neutral point member  37  are located above the motor axis J 1 . Note that a plurality of sets of the coil lead wires  37 U,  37 V, and  37 W and the neutral point member  37  may be provided. 
     The binding member  38  is an annular member that collectively binds the coil lead wires  36 U,  36 V,  36 W,  37 U,  37 V, and  37 W covered with the insulating tube  39  and the coil end  33   b . A plurality of the binding members  38  is provided.  FIG. 5  illustrates two binding members  38  that bind the coil lead wires  37 U,  37 V, and  37 W and the coil end  33   b . The binding member  38  may be, for example, a string or a plastic band. 
     As illustrated in  FIG. 1 , the bearings  26  and  27  are arranged to rotatably support the rotor  20 . Each of the bearings  26  and  27  is, for example, a ball bearing. The bearing  26  is a bearing arranged to rotatably support a portion of the rotor  20  which is located on the right side (−Y side) of the stator core  32 . In the present embodiment, the bearing  26  is arranged to support a portion of the shaft  21  which is located on the right side of a portion of the shaft  21  to which the rotor body  24  is fixed. The bearing  26  is held in a wall portion of the motor housing  81 , covering the right side of the rotor  20  and the stator  30 . 
     The bearing  27  is a bearing arranged to rotatably support a portion of the rotor  20  which is located on the left side (+Y side) of the stator core  32 . In the present embodiment, the bearing  27  is arranged to support a portion of the shaft  21  which is located on the left side of the portion of the shaft  21  to which the rotor body  24  is fixed. The bearing  27  is held by the partition  61   c.    
     As illustrated in  FIG. 4 , the motor  2  includes a first busbar  100  and a terminal block  110 . That is, the drive device  1  includes the first busbar  100  and the terminal block  110 . The first busbar  100  is a busbar to which the terminal portions  34 U,  34 V, and  34 W are connected. In the present embodiment, for example, three first busbars  100  are provided. One ends of the three first busbars  100  are connected to the terminal portions  34 U,  34 V, and  34 W, respectively. The other ends of the three first busbars  100  are connected to respective portions of the three second busbars  8   d  protruding to the outside of the inverter case  8   a.    
     The terminal block  110  is a member that holds the first busbar  100 . The terminal block  110  is arranged to extend in the axial direction. In the present embodiment, the terminal block  110  is supported by a rear (−X side) and the upper portion of the outer circumferential surface of the stator core body  32   a . In the present embodiment, the first busbar  100  and the terminal block  110  are provided in a portion located between the stator  30  and the inverter unit  8  in the front-rear direction in the motor housing  81 . 
     As illustrated in  FIG. 1 , the transmission device  3  is housed in the gear housing  82  of the housing  6 . The transmission device  3  is connected to the motor  2 . In more detail, the transmission device  3  is connected to the end of the shaft  21  on the left side. The transmission device  3  includes the speed reducer  4  and the differential  5 . A torque outputted from the motor  2  is transferred to the differential  5  through the speed reducer  4 . 
     The speed reducer  4  is connected to the motor  2 . The speed reducer  4  is arranged to increase the torque outputted from the motor  2  in accordance with a reduction ratio while reducing the rotation speed of the motor  2 . The speed reducer  4  is arranged to transfer the torque outputted from the motor  2  to the differential  5 . The speed reducer  4  includes the first gear  41 , a second gear  42 , a third gear  43 , and an intermediate shaft  45 . 
     The torque outputted from the motor  2  is transferred to a ring gear  51  of the differential  5  through the shaft  21 , the first gear  41 , the second gear  42 , the intermediate shaft  45 , and the third gear  43  in this order. 
     The differential  5  is connected to the motor  2  through the speed reducer  4 . The differential  5  is a device arranged to transfer the torque outputted from the motor  2  to wheels of the vehicle. The differential  5  is arranged to transfer the same torque to axles  55  of left and right wheels while absorbing a difference in speed between the left and right wheels when the vehicle is turning. The differential  5  has the ring gear  51 . The ring gear  51  is arranged to rotate about a differential axis J 3  parallel to the motor axis J 1 . The torque outputted from the motor  2  is transferred to the ring gear  51  through the speed reducer  4 . 
     The lower end of the ring gear  51  is located below the oil level Sg of the oil pool P in the gear housing  82 . Accordingly, the lower end of the ring gear  51  is immersed in the oil O in the gear housing  82 . In the present embodiment, the oil level Sg of the oil pool P is located below the differential axis J 3  and the axle  55 . 
     The drive device  1  is provided with the oil passage  90 , through which the oil O circulates in the housing  6 . The oil passage  90  is a channel of the oil O along which the oil O is fed from the oil pool P to the motor  2  and is led back to the oil pool P. The oil passage  90  is provided across the inside of the motor housing  81  and the inside of the gear housing  82 . 
     Note that the term “oil passage” as used herein refers to a channel of oil. Therefore, the concept of “oil passage” includes not only a “flow passage”, in which a steady flow of an oil in one direction is generated, but also a channel in which the oil is allowed to temporarily stay, and a channel along which the oil drips. Examples of the channel in which the oil is allowed to temporarily stay include a reservoir arranged to store the oil. 
     The oil passage  90  includes a first oil passage  91  and a second oil passage  92 . Each of the first oil passage  91  and the second oil passage  92  is arranged to circulate the oil O in the housing  6 . The first oil passage  91  includes a scraping-up channel  91   a , a shaft feed channel  91   b , an intra-shaft channel  91   c , and an intra-rotor channel  91   d . The first oil passage  91  is provided in its channel with a first reservoir  93 . The first reservoir  93  is provided in the gear housing  82 . 
     The scraping-up channel  91   a  is a channel along which the oil O is scraped up from the oil pool P by rotation of the ring gear  51  of the differential  5  to be received by the first reservoir  93 . The first reservoir  93  is arranged to open upward. The first reservoir  93  receives a portion of the oil O which has been scraped up by the ring gear  51 . The first reservoir  93  also receives portions of the oil O which have been scraped up by the second gear  42  and the third gear  43  in addition to the ring gear  51  when, for example, the oil level Sg of the oil pool P is at a high level, e.g., immediately after the motor  2  is started. 
     The shaft feed channel  91   b  is arranged to lead the oil O from the first reservoir  93  into the hollow portion  22  of the shaft  21 . The intra-shaft channel  91   c  allows the oil O to flow through the hollow portion  22  of the shaft  21 . The intra-rotor channel  91   d  is a channel along which the oil O passes through the communicating hole  23  of the shaft  21  and an interior of the rotor body  24 , and is scattered to the stator  30 . 
     In the intra-shaft channel  91   c , a centrifugal force is applied to the oil O in the rotor  20  due to the rotation of the rotor  20 . Thus, the oil O is continuously scattered radially outward from the rotor  20 . The scattering of the oil O generates a negative pressure in a channel in the rotor  20 , causing the oil O accumulated in the first reservoir  93  to be sucked into the rotor  20 , so that the channel in the rotor  20  is filled with the oil O. 
     A portion of the oil O which has reached the stator  30  absorbs heat from the stator  30 . The oil O having cooled the stator  30  drips downward to accumulate in a lower region in the motor housing  81 . The oil O having accumulated in the lower region in the motor housing  81  moves to the gear housing  82  through the partition opening  68  provided in the partition  61   c . In the above-described manner, the first oil passage  91  feeds the oil O to the rotor  20  and the stator  30 . 
     In the second oil passage  92 , the oil O is raised from the oil pool P to above the stator  30  to be supplied to the stator  30 . That is, in the present embodiment, the drive device  1  includes the second oil passage  92  as an oil passage for supplying the oil O to the stator  30  from above. The second oil passage  92  is provided with an oil pump  96 , a cooler  97 , and a second reservoir  10 . The second oil passage  92  includes a first flow passage  92   a , a second flow passage  92   b , and a third flow passage  92   c.    
     Each of the first flow passage  92   a , the second flow passage  92   b , and the third flow passage  92   c  is defined in a wall portion of the housing  6 . The first flow passage  92   a  connects the oil pool P and the oil pump  96 . The second flow passage  92   b  connects the oil pump  96  and the cooler  97 . The third flow passage  92   c  extends upward from the cooler  97 . The third flow passage  92   c  is provided on the wall portion of the motor housing  81 . That is, the motor  2  includes the third flow passage  92   c . As illustrated in  FIGS. 6 and 7 , the third flow passage  92   c  includes a supply port  92   ca  that opens inside the motor housing  81  above the stator  30 . The supply port  92   ca  supplies the oil O to the inside of the motor housing  81 . 
     The oil pump  96  is an electric pump driven by electricity. As illustrated in  FIG. 1 , the oil pump  96  sucks up the oil O from the oil pool P through the first flow passage  92   a , and supplies the oil O to the motor  2  through the second flow passage  92   b , the cooler  97 , the third flow passage  92   c , and the second reservoir  10 . 
     The cooler  97  cools the oil O passing through the second oil passage  92 . The second flow passage  92   b  and the third flow passage  92   c  are connected to the cooler  97 . The second flow passage  92   b  and the third flow passage  92   c  are connected to each other through an internal flow passage of the cooler  97 . A cooling water pipe  97   j  for passing cooling water cooled by a radiator (not illustrated) is connected to the cooler  97 . The oil O passing through the inside of the cooler  97  is cooled by heat exchange with the cooling water passing through the cooling water pipe  97   j . The inverter unit  8  is provided in the cooling water pipe  97   j . The cooling water passing through the cooling water pipe  97   j  cools the inverter unit  8 . 
     The second reservoir  10  constitutes a part of the second oil passage  92 . The second reservoir  10  is located inside the motor housing  81 . The second reservoir  10  is located above the stator  30 . As illustrated in  FIG. 6 , the second reservoir  10  is supported by the stator  30  from below, and is provided in the motor  2 . The second reservoir  10  is made of, for example, a resin material. 
     In the following description, for an object, the side closer to the center of the stator  30  in the axial direction may be referred to as “axially inward”, and the side away from the center of the stator  30  in the axial direction may be referred to as “axially outward”. 
     In the present embodiment, the second reservoir  10  has a gutter shape that opens upward and extends in a substantially rectangular frame shape when viewed in the vertical direction. The second reservoir  10  stores the oil O. In the present embodiment, the second reservoir  10  stores the oil O supplied in the motor housing  81  via the third flow passage  92   c . That is, in the present embodiment, the third flow passage  92   c  corresponds to a supply oil passage that supplies the oil O to the second reservoir  10 . In the present embodiment, since the second reservoir  10  has a gutter shape opening upward, the oil O can be easily supplied to the second reservoir  10  by allowing the oil O to flow out of the third flow passage  92   c  above the second reservoir  10 . As illustrated in  FIGS. 6 to 8 , the second reservoir  10  includes a first oil passage portion  11 , a second oil passage portion  12 , a pair of third oil passage portions  13 A and  13 B, a first fixing portion  18 , and support ribs  16   a  and  16   b.    
     The first oil passage portion  11  and the second oil passage portion  12  extend in the axial direction. The first oil passage portion  11  and the second oil passage portion  12  are disposed at an interval in the front-rear direction. As illustrated in  FIG. 7 , the second oil passage portion  12  and the first oil passage portion  11  sandwich the motor axis J 1  when viewed in the vertical direction. The first oil passage portion  11  is located on the front side relative to the motor axis J 1 . The second oil passage portion  12  is located on the rear side relative to the motor axis J 1 . 
     The pair of third oil passage portions  13 A and  13 B extends in the front-rear direction. The pair of third oil passage portions  13 A and  13 B is disposed at an interval in the axial direction. The pair of third oil passage portions  13 A and  13 B connects the first oil passage portion  11  and the second oil passage portion  12 . In the present embodiment, one third oil passage portion  13 A of the pair of third oil passage portions  13 A and  13 B connects the right end of the first oil passage portion  11  and the right end of the second oil passage portion  12 . In the present embodiment, the other third oil passage portion  13 B of the pair of third oil passage portions  13 A and  13 B connects the left end of the first oil passage portion  11  and the left end of the second oil passage portion  12 . The first oil passage portion  11 , the second oil passage portion  12 , and the pair of third oil passage portions  13 A and  13 B each have a substantially U-shaped gutter-like cross section that opens upward. 
     The first oil passage portion  11  is located above the stator core  32 . In the present embodiment, the first oil passage portion  11  is located in front of the fixing portion  32   b , among the fixing portions  32   b , that protrudes upward. The first oil passage portion  11  includes a first bottom wall portion  11   a  and a pair of first side wall portions  11   b  and  11   c.    
     The first bottom wall portion  11   a  extends in the axial direction. The first bottom wall portion  11   a  has a plate shape with the plate face oriented in the vertical direction. As illustrated in  FIG. 9 , the first bottom wall portion  11   a  faces the outer circumferential surface of the stator core body  32   a  via a gap. The upper side face of the first bottom wall portion  11   a  includes a flat portion  11   aa  and inclined portions  11   ab  and  11   ac.    
     The first oil passage portion  11  is located below the supply port  92   ca . As a result, the first oil passage portion  11  receives the oil O supplied into the motor housing  81  from the supply port  92   ca . That is, the third flow passage  92   c  as a supply oil passage supplies the oil O to a portion of the second reservoir  10  located on the front side (+X side) of the motor axis J 1 . In the present embodiment, the supply port  92   ca  is disposed radially inward relative to the axial ends on the opposite sides of the first oil passage portion  11 . As illustrated in  FIG. 7 , the supply port  92   ca  overlaps with the left portion of the first bottom wall portion  11   a  when viewed in the vertical direction. 
     As illustrated in  FIGS. 7 to 9 , the first oil passage portion  11  includes a first oil supply port  17   a  for supplying the oil O to the stator  30  from above. In the present embodiment, the first oil supply port  17   a  is a through hole that penetrates the first bottom wall portion  11   a  in the vertical direction. The first oil supply port  17   a  has, for example, a circular shape. The first oil supply port  17   a  is located above the stator  30 . More specifically, the first oil supply port  17   a  is located above the stator core  32  at a distance. As illustrated in  FIG. 9 , part of the oil O supplied to the first oil passage portion  11  flows out below the first oil passage portion  11  through the first oil supply port  17   a , and is supplied to the stator core  32  from above. Thus, in the present embodiment, the first oil supply port  17   a  supplies the oil O to the stator core  32  from above. 
     In the present embodiment, a plurality of the first oil supply ports  17   a  is provided along the axial direction in which the first oil passage portion  11  extends. In the present embodiment, for example, three first oil supply ports  17   a  are provided. 
     As illustrated in  FIG. 6 , the second oil passage portion  12  is located above the stator core  32 . In the present embodiment, the second oil passage portion  12  is located behind the fixing portion  32   b , among the fixing portions  32   b , that protrudes upward. Therefore, the first oil passage portion  11  and the second oil passage portion  12  are disposed so as to sandwich, in the front-rear direction, the fixing portion  32   b , of the fixing portions  32   b , which protrudes upward. The dimension of the second oil passage portion  12  in the front-rear direction is smaller than the dimension of the first oil passage portion  11  in the front-rear direction. The lower end of the second oil passage portion  12  is located lower than the lower end of the first oil passage portion  11 . The second oil passage portion  12  includes a second bottom wall portion  12   a  and a pair of second side wall portions  12   b  and  12   c.    
     The second bottom wall portion  12   a  includes a front portion  12   aa  and a rear portion  12   ab . The second oil passage portion  12  is provided with the first fixing portion  18 . The first fixing portion  18  is provided at a left portion of the second oil passage portion  12  relative to the center in the axial direction. The first fixing portion  18  includes a through hole  18   a  that penetrates the first fixing portion  18  in the axial direction. Although not illustrated, a screw to be fastened into the motor housing  81  passes through the through hole  18   a . The first fixing portion  18  is fixed to the housing  6  by a screw passing through the through hole  18   a.    
     As illustrated in  FIG. 10 , the lower end of the first fixing portion  18  is connected to the second side wall portion  12   b  and the second side wall portion  12   c  so as to be over them. The first fixing portion  18  closes part of the upper opening of the second oil passage portion  12 . The lower end of the first fixing portion  18  includes a portion located inside the second oil passage portion  12 . A portion, of the first fixing portion  18 , located inside the second oil passage portion  12  is provided with a recess portion  18   b  that is recessed upward. Therefore, in the portion, of the second oil passage portion  12 , where the first fixing portion  18  is provided, it is easy to secure the internal flow passage area. 
     As illustrated in  FIGS. 7 and 8 , the second oil passage portion  12  includes second oil supply ports  17   b  and  17   e  for supplying the oil O to the stator  30  from above. In the present embodiment, the second oil supply ports  17   b  and  17   e  are through holes that penetrate the second bottom wall portion  12   a  in the vertical direction. The second oil supply ports  17   b  and  17   e  are provided at a connection portion between the front portion  12   aa  and the rear portion  12   ab . The second oil supply port  17   b  is, for example, circular shape. The second oil supply port  17   e  is, for example, rectangular. 
     The second oil supply ports  17   b  and  17   e  are located above the stator  30 . More specifically, the second oil supply ports  17   b  and  17   e  are located above the stator core  32 . At least part of the oil O supplied to the second oil passage portion  12  flows out below the second oil passage portion  12  through the second oil supply ports  17   b  and  17   e , and is supplied to the stator core  32  from above. Thus, in the present embodiment, the second oil supply ports  17   b  and  17   e  supply the oil O to the stator core  32  from above. 
     In the present embodiment, a plurality of the second oil supply ports  17   b  is provided along the axial direction in which the second oil passage portion  12  extends. In the present embodiment, for example, five second oil supply ports  17   b  are provided. 
     As illustrated in  FIG. 7 , the third oil passage portion  13 A is located on the right side of the stator core  32 . The third oil passage portion  13 A is located above the coil end  33   a . The third oil passage portion  13 B is located on the left side of the stator core  32 . The third oil passage portion  13 B is located above the coil end  33   b . In the present embodiment, the third oil passage portion  13 A and the third oil passage portion  13 B have substantially the same configuration except that they are disposed substantially symmetrically in the axial direction. Therefore, in the following description, only the third oil passage portion  13 A may be described as a representative of the third oil passage portion  13 A and the third oil passage portion  13 B. 
     The third oil passage portion  13 A includes a third bottom wall portion  13 Aa and a pair of third side wall portions  13 Ab and  13 Ac. The third bottom wall portion  13 Aa extends in the front-rear direction. The third bottom wall portion  13 Aa has a plate shape with the plate face oriented in the vertical direction. The front end of the third bottom wall portion  13 Aa is connected to the right end of the first bottom wall portion  11   a . The rear end of the third bottom wall portion  13 Aa is connected to the right end of the second bottom wall portion  12   a . As illustrated in  FIGS. 6 and 8 , a central portion of the third bottom wall portion  13 Aa in the front-rear direction is curved in an arc shape that protrudes upward along the outer circumferential surface above the coil end  33   a . The rear end of the third bottom wall portion  13 Aa is located lower than the front end of the third bottom wall portion  13 Aa. 
     As illustrated in  FIG. 6 , the third side wall portion  13 Ab protrudes upward from an axially inner (left side) edge of the third bottom wall portion  13 Aa. The third side wall portion  13 Ac protrudes upward from an axially outer (right side) edge of the third bottom wall portion  13 Aa. The pair of third side wall portions  13 Ab and  13 Ac extend in the front-rear direction. The pair of third side wall portions  13 Ab and  13 Ac has a plate shape with the plate face oriented in the axial direction. The front end of the third side wall portion  13 Ab is connected to the right end of the first side wall portion lib. The rear end of the third side wall portion  13 Ab is connected to the right end of the second side wall portion  12   b.    
     The third side wall portion  13 Ab includes a second fixing portion  13 Ad at the center in the front-rear direction. The screw for fixing the stator core  32  to the motor housing  81 , together with the stator core  32 , fastens and fixes the second fixing portion  13 Ad to the motor housing  81 . The second reservoir  10  is fixed to the housing  6  by the first fixing portion  18  and the second fixing portion  13 Ad being screwed to the motor housing  81 . Thereby, the second reservoir  10  can be firmly fixed. 
     The front end of the third side wall portion  13 Ac is connected to the right end of the first side wall portion  11   c . The rear end of the third side wall portion  13 Ac is connected to the right end of the second side wall portion  12   c . The front end of the third side wall portion  13 Ac is a bent portion  13 Ai that is curved toward and is smoothly connected to the first side wall portion  11   c . The rear end of the third side wall portion  13 Ac is a bent portion  13 Aj that is curved toward and is smoothly connected to the second side wall portion  12   c.    
     The bent portion  13 Ai includes a protrusion  13 Ae protruding upward. Although not illustrated, the upper end of the protrusion  13 Ae is in contact with, for example, the upper face of the inner wall face of the motor housing  81 . As a result, the oil O flowing into the third oil passage portion  13 A can be prevented from flowing over the bent portion  13 Ai, and the oil O can be prevented from leaking from the third oil passage portion  13 A. 
     As illustrated in  FIGS. 7 and 8 , the third oil passage portion  13 A includes third oil supply ports  17   c  and  17   f  for supplying the oil O to the stator  30  from above. In the present embodiment, the third oil supply ports  17   c  and  17   f  are through holes that penetrate the third bottom wall portion  13 Aa in the vertical direction. The third oil supply port  17   c  is, for example, circular shape. The third oil supply port  17   f  is, for example, rectangular elongated in the front-rear direction. The third oil supply ports  17   c  and  17   f  are located above the stator  30 . More specifically, the third oil supply ports  17   c  and  17   f  are located above the coil end  33   a . Part of the oil O supplied to the third oil passage portion  13 A flows out below the third oil passage portion  13 A through the third oil supply ports  17   c  and  17   f , and is supplied to the coil end  33   a  from above. Thus, in the present embodiment, the third oil supply ports  17   c  and  17   f  supply the oil O to the coil end  33   a  from above. 
     In the present embodiment, a plurality of the third oil supply ports  17   c  is provided in the direction in which the third oil passage portion  13 A extends, that is, along the front-rear direction. In the present embodiment, for example, four third oil supply ports  17   c  are provided in the third oil passage portion  13 A. More specifically, the third oil passage portion  13 A is provided with a total of four third oil supply ports  17   c  where the third oil supply ports  17   c  are disposed in two rows in the axial direction with each row having two third oil supply ports  17   c  disposed at intervals in the front-rear direction. 
     The third oil supply port  17   f  is provided between two sets of third oil supply ports  17   c  arranged at an interval in the front-rear direction. The third oil supply port  17   f  is provided at the center of the third oil passage portion  13 A in the front-rear direction. The third oil supply port  17   f  extends in the direction in which the third oil passage portion  13 A extends, that is, in the front-rear direction. The opening area of the third oil supply port  17   f  is larger than the opening area of the third oil supply port  17   c . The axial dimension of the third oil supply port  17   f  is twice or more the inner diameter of the third oil supply port  17   c . The dimension of the third oil supply port  17   f  in the front-rear direction is four times or more the inner diameter of the third oil supply port  17   c.    
     As illustrated in  FIG. 7 , the third oil passage portion  13 A includes a bearing oil supply portion  13 Af that protrudes axially outward (to the right side). The bearing oil supply portion  13 Af is located at the center of the third oil passage portion  13 A in the front-rear direction. The bearing oil supply portion  13 Af is located above the bearing  26 . The bearing oil supply portion  13 Af includes a recess groove portion  13 Ah and a fifth oil supply port  17   d . That is, the second reservoir  10  includes the recess groove portion  13 Ah and the fifth oil supply port  17   d . The recess groove portion  13 Ah is provided on an axially outer edge of the upper side face of the third bottom wall portion  13 Aa. The recess groove portion  13 Ah is recessed downward and extends in the front-rear direction. The fifth oil supply port  17   d  is provided on the groove bottom face of the recess groove portion  13 Ah. The fifth oil supply port  17   d  is a through hole that penetrates the third bottom wall portion  13 Aa in the vertical direction. The fifth oil supply port  17   d  is located above the bearing  26 . The fifth oil supply port  17   d  supplies the oil O in the recess groove portion  13 Ah to the bearing  26  from above. Therefore, the oil O can be supplied to the bearing  26  via the second reservoir  10  as lubricating oil. 
     As illustrated in  FIG. 6 , the third oil passage portion  13 B includes a third bottom wall portion  13 Ba and a pair of third side wall portions  13 Bb and  13 Bc. The third side wall portion  13 Bb does not include the second fixing portion  13 Ad unlike the third side wall portion  13 Ab. The front end of the third side wall portion  13 Bc is a bent portion  13 Bi that is curved toward and is smoothly connected to the first side wall portion  11   c . The rear end of the third side wall portion  13 Bc is a bent portion  13 Bj that is curved toward and is smoothly connected to the second side wall portion  12   c . The bent portion  13 Bi includes a protrusion  13 Be protruding upward. The upper end of the protrusion  13 Be is located lower than the upper end of the protrusion  13 Ae. 
     The third oil passage portion  13 B includes a bearing oil supply portion  13 Bf. As illustrated in  FIG. 7 , the bearing oil supply portion  13 Bf includes a recess groove portion  13 Bh and the fifth oil supply port  17   d . The fifth oil supply port  17   d  of the bearing oil supply portion  13 Bf supplies the oil O to the bearing  27  from above. 
     Therefore, the oil O can be supplied to the bearing  27  via the second reservoir  10  as lubricating oil. The third oil passage portion  13 B includes a plurality of the third oil supply ports  17   c  and  17   f , as in the third oil passage portion  13 A. The third oil supply ports  17   c  and  17   f  provided in the third oil passage portion  13 B supply the oil O to the coil end  33   b  from above. 
     As illustrated in  FIGS. 6 and 7 , the third oil passage portion  13 B includes a guide wall portion  13 Bd. The guide wall portion  13 Bd protrudes upward from the upper side face of the third bottom wall portion  13 Ba. More specifically, the guide wall portion  13 Bd protrudes upward from the axially inner (right side) edge of the recess groove portion  13 Bh of the upper side face of the third bottom wall portion  13 Ba. The guide wall portion  13 Bd linearly extends rearward from the bent portion  13 Bi. As illustrated in  FIG. 7 , the rear end of the guide wall portion  13 Bd is located on the front side relative to the fifth oil supply port  17   d  of the bearing oil supply portion  13 Bf. The guide wall portion  13 Bd guides the oil O flowing from the first oil passage portion  11  to the third oil passage portion  13 B to the rear side. 
     As illustrated by the dashed arrows in  FIGS. 6 and 9 , the oil O supplied from the third flow passage  92   c  to the first oil passage portion  11  via the supply port  92   ca  branches off on both sides of the first oil passage portion  11  in the longitudinal direction, that is, on both sides in the axial direction. More specifically, the oil O supplied to the flat portion  11   aa  from the supply port  92   ca  flows along the inclined portions  11   ab  and  11   ac  located on both sides of the flat portion  11   aa  in the axial direction. Since the inclined portions  11   ab  and  11   ac  become lower as going away from the flat portion  11   aa  in the axial direction, the oil O supplied to the flat portion  11   aa  can be suitably caused to flow in both axial directions along the inclined portions  11   ab  and  11   ac.    
     Part of the oil O supplied to the first oil passage portion  11  is supplied to the stator core  32  from above via the first oil supply port  17   a . Another part of the oil O supplied to the first oil passage portion  11  flows into the third oil passage portions  13 A and  13 B. 
     Part of the oil O flowing into the third oil passage portions  13 A and  13 B is supplied to the coil ends  33   a  and  33   b  from above via the third oil supply ports  17   c  and  17   f . Another part of the oil O flowing into the third oil passage portions  13 A and  13 B flows into the recess groove portions  13 Ah,  13 Bh, and is supplied to the bearings  26  and  27  from above via the fifth oil supply port  17   d . Still another part of the oil O flowing into the third oil passage portions  13 A and  13 B flows into the second oil passage portion  12  from both sides in the axial direction. 
     Here, an inclined face  12   d  that becomes lower as going leftward is provided at the right end of the second bottom wall portion  12   a . Therefore, the oil O flowing into the second oil passage portion  12  from the rear end of the third oil passage portion  13 A can flow along the inclined face  12   d . This makes it easy for the oil O in the third oil passage portion  13 A to flow into the second oil passage portion  12 . 
     Further, the third oil passage portion  13 B is provided with the guide wall portion  13 Bd for guiding the oil O flowing from the first oil passage portion  11  to the third oil passage portion  13 B to the rear side. For this reason, the oil O that has flowed into the third oil passage portion  13 B easily flows in the front-rear direction along the third oil passage portion  13 B, and the oil O easily flows from the third oil passage portion  13 B to the second oil passage portion  12 . 
     The oil O flowing into the second oil passage portion  12  flows inward in the axial direction from each of the third oil passage portions  13 A and  13 B. The oil O flowing into the second oil passage portion  12  is supplied to the stator core  32  from above through the second oil supply ports  17   b  and  17   e.    
     The oil O supplied from the second reservoir  10  to the stator  30  and the bearings  26  and  27  is dripped downward and accumulates in a lower region in the motor housing  81 . The oil O having accumulated in the lower region in the motor housing  81  moves to the gear housing  82  through the partition opening  68  provided in the partition  61   c . As described above, the second oil passage  92  supplies the oil O to the stator  30  and the bearings  26  and  27 . 
     The third oil passage portion  13 A connects the right end of the first oil passage portion  11  and the right end of the second oil passage portion  12 , and the third oil passage portion  13 B connects the left end of the first oil passage portion  11  and the left end of the second oil passage portion  12 . Therefore, the shape of the second reservoir  10  can be made to be a substantially rectangular frame shape. This facilitates the flow of the oil O in the first oil passage portion  11  to the second oil passage portion  12 , and facilitates the flow of the oil O in the entire second reservoir  10 . 
     As illustrated in  FIG. 3 , the drive device  1  includes a temperature sensor  70  capable of detecting the temperature of the motor  2 . The type of the temperature sensor  70  is not particularly limited as long as the temperature of the motor  2  can be detected. The temperature of the motor  2  includes the temperature of the stator  30 . In the present embodiment, the temperature sensor  70  can detect the temperature of the stator  30 . The temperature sensor  70  has, for example, a rod shape extending in one direction. In the present embodiment, the temperature sensor  70  extends obliquely in a direction slightly inclined in the front-rear direction with respect to the vertical direction. 
     The temperature sensor  70  is provided in a portion of the coil assembly  33  located on the rear side (−X side) of the motor axis J 1 . In the present embodiment, the temperature sensor  70  is provided in a portion of the coil assembly  33  located on the rear side of the shaft  21 . The temperature sensor  70  is located between the shaft  21  and the inverter unit  8  in the front-rear direction. In the present embodiment, the temperature sensor  70  is provided at the coil end  33   b . More specifically, at least a part of the temperature sensor  70  is embedded in the coil end  33   b . Therefore, for example, by inserting the temperature sensor  70  into the coil end  33   b  and embedding at least a part thereof, the temperature sensor  70  can be easily held with respect to the coil end  33   b . In the present embodiment, the temperature sensor  70  is inserted into the coil end  33   b  and substantially entirely embedded in the coil end  33   b.    
     The temperature sensor  70  is located below the terminal portions  34 U,  34 V, and  34 W and above the lower end of the rotor  20 , that is, above the lower end of the rotor body  24 . Here, the oil level Sm of the oil O stored in the motor housing  81  is located below the lower end of the rotor  20 . Therefore, in the present embodiment, the temperature sensor  70  is located above the oil level Sm of the oil O. The temperature sensor  70  is located below the first busbar  100  and the terminal block  110 . 
     As illustrated in  FIG. 5 , the temperature sensor  70  is provided in a portion of the coil end  33   b  bound by the binding member  38 , and is pressed from the axial direction by the coil lead wires  37 U,  37 V, and  37 W covered with the insulating tube  39 . Therefore, it is possible to suitably suppress the temperature sensor  70  from being detached from the coil end  33   b . In the present embodiment, the temperature sensor  70  is inserted into and held by the coil end  33   b . Therefore, the coil lead wires  37 U,  37 V, and  37 W bound by the binding member  38  press the temperature sensor  70  from the left side (+Y side) via the portions of the coil end  33   b  located between the coil lead wires  37 U,  37 V, and  37 W and the temperature sensor  70  in the axial direction. In  FIG. 5 , the temperature sensor  70  passes through the inside of one of the two binding members  38 . The temperature sensor  70  may pass through the inside of the two binding members  38 . Further, the temperature sensor  70  may be disposed in contact with the end of the coil end  33   b  in the left-right direction and fixed to the coil end  33   b  by the binding member  38 . That is, it is also possible to adopt a configuration in which the temperature sensor  70  is not inserted into the coil end  33   b . In this configuration, it is possible to suppress an increase in the number of assembling steps of the temperature sensor  70 . 
     In the present embodiment, a plurality of temperature sensors  70  is provided. In the present embodiment, two temperature sensors  70 , a first temperature sensor  71  and a second temperature sensor  72 , are provided. Both the first temperature sensor  71  and the second temperature sensor  72  are provided only in one coil end  33   b  of the two coil ends  33   a  and  33   b . As a result, it is possible to suppress an increase in the number of assembling steps of the temperature sensor  70  as compared with a configuration in which the temperature sensor  70  is provided in each of the two coil ends  33   a  and  33   b . As illustrated in  FIG. 3 , the first temperature sensor  71  and the second temperature sensor  72  are arranged in parallel to each other, for example, in the front-rear direction. 
     The detection result of the first temperature sensor  71  is sent to the control unit  8   b  via a cable  71   a  extending from the first temperature sensor  71 . The detection result of the second temperature sensor  72  is sent to the control unit  8   b  via a cable  72   a  extending from the second temperature sensor  72 . The cables  71   a  and  72   a  extend upward from the first temperature sensor  71  and the second temperature sensor  72 , respectively, and are drawn along the outer circumferential surface of the coil end  33   b , for example. 
     For example, in a case where the drive of the drive device  1  is controlled on the basis of the temperature of the motor  2 , it is required that the temperature of the motor  2  can be accurately detected. The control of the drive device  1  based on the temperature of the motor  2  includes, for example, flow rate control of the oil O sent to the motor  2  by the oil pump  96 . For example, when the temperature of the motor  2  is higher than a predetermined temperature, the control unit  8   b  decreases the temperature of the motor  2  by increasing the flow rate of the oil O sent from the oil pump  96  to the motor  2 . As a result, it is possible to suppress the temperature of the motor  2  from becoming too high, and it is possible to suppress the occurrence of a defect in the drive device  1 . 
     Here, since the temperature of the motor  2  varies depending on the portion of the motor  2 , the detected temperature varies depending on which portion of the motor  2  the temperature is detected. When the drive device  1  is controlled based on the temperature of the motor  2 , it is preferable to detect the highest temperature of the motor  2 . This is because, for example, the motor  2  can be suitably cooled when the flow rate of the oil pump  96  is controlled to adjust the degree of cooling of the motor  2  as described above. 
     As the flow rate control of the oil O, for example, the control unit  8   b  compares the values of the detection results of the first temperature sensor  71  and the second temperature sensor  72 . Next, the control unit  8   b  calculates a drive signal for driving the oil pump  96  on the basis of a detection result of a high value as a result of the comparison, and outputs the drive signal to the oil pump  96 . Note that the control unit  8   b  determines that the detection result of the other temperature sensor  70  has a higher value than the detection signal of the temperature sensor  70  in a case of failure, disconnection, or the like of one temperature sensor  70  when comparing the detection signals of the temperature sensors  70 . The control unit  8   b  increases the value of the drive signal as the value of the detection result of the temperature sensor  70  used to calculate the drive signal increases. That is, the control unit  8   b  increases the amount of the oil O sent by the oil pump  96  and increases the supply amount of the oil O to the stator  30  as the temperature of the motor  2  is higher. For example, the control unit  8   b  performs the above-described flow rate control of the oil O at a constant cycle. 
     In the motor  2 , the temperature of the coil  31  serving as a heat source is the highest. However, since the temperature of the coil  31  also varies depending on the portion of the coil  31 , the highest temperature in the motor  2  may not be detected only by detecting the temperature of the coil  31 . Therefore, in order to detect the highest temperature in the motor  2 , it is necessary to provide the temperature sensor  70  in the portion having the highest temperature in the coil  31 . 
     In the present embodiment, the oil O is supplied to the stator  30  from above by the second oil passage  92 . Therefore, in the portion to which the oil O is supplied, the temperature of the coil  31  tends to be relatively low. However, in the portion of the coil  31  located on the side on which the terminal portions  34 U,  34 V, and  34 W are provided in the front-rear direction, the oil O is blocked by the terminal portions  34 U,  34 V, and  34 W and the coil lead wires gathering around the terminal portions  34 U,  34 V, and  34 W, and the oil O hardly flows below the terminal portions  34 U,  34 V, and  34 W. Therefore, a portion of the coil  31  located on the rear side (−X side) where the terminal portions  34 U,  34 V, and  34 W are provided and located below the terminal portions  34 U,  34 V, and  34 W is likely to have a relatively high temperature. 
     On the other hand, the oil O is stored inside the motor housing  81 . Therefore, the lower portion of the coil  31  immersed in the oil O is cooled by the oil O, and the temperature tends to be relatively low. Therefore, in the coil  31 , on the rear side (−X side) where the terminal portions  34 U,  34 V, and  34 W are provided, the portion located below the terminal portions  34 U,  34 V, and  34 W and above the lower portion immersed in the oil O is likely to have the highest temperature. 
     To take a measure for this, according to the present embodiment, the temperature sensor  70  capable of detecting the temperature of the motor  2  is provided in the portion of the coil assembly  33  located on the rear side (−X side) of the motor axis J 1 , and is located below the terminal portions  34 U,  34 V, and  34 W and above the lower end of the rotor  20 . Therefore, the temperature sensor  70  is easily provided in a portion where the temperature is most likely to be high in the coil  31  described above. As a result, the temperature sensor  70  can easily detect the highest temperature among the temperatures of the coil  31 . Therefore, according to the present embodiment, it is easy to accurately detect the highest temperature among the temperatures of the motor  2  in the drive device  1 . As a result, the motor  2  can be suitably cooled when the flow rate of the oil O sent from the oil pump  96  to the motor  2  is controlled based on the temperature of the motor  2  as described above. Therefore, it is possible to appropriately cool the motor  2  and drive the drive device  1  with high energy efficiency. 
     In the configuration in which the maximum temperature of the motor  2  cannot be accurately detected, even when the maximum temperature of the motor  2  is actually low, it is difficult to reduce the supply amount of the oil O to the stator  30  since the stator  30  is suppressed from becoming high temperature. To take a measure for this, in the present embodiment, the control unit  8   b  controls the supply amount of the oil O to the stator  30  on the basis of the highest temperature of the motor  2  accurately detected. Therefore, the control unit  8   b  can reduce the amount of the oil O flowing to the motor housing  81  when the maximum temperature of the motor  2  is low. Therefore, it is possible to suppress an increase in the oil level Sm of the oil O stored in the motor housing  81 , and eventually, it is possible to suppress the oil O from becoming a resistance of the rotor  20 . 
     According to the present embodiment, the temperature sensor  70  is located above the oil level Sm of the oil O stored in the motor housing  81 . Therefore, the temperature sensor  70  can be more suitably provided in the portion where the temperature is most likely to be high in the coil  31  described above. As a result, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     According to the present embodiment, the temperature sensor  70  is provided at the coil end  33   b . Therefore, the temperature sensor  70  can be brought into direct contact with the coil  31 . As a result, the temperature of the coil  31  can be more suitably detected by the temperature sensor  70 . Therefore, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     According to the present embodiment, at least a part of the temperature sensor  70  is embedded in the coil end  33   b . Therefore, the temperature sensor  70  can be brought into close contact with the coil  31 , and the temperature of the coil  31  can be more suitably detected by the temperature sensor  70 . Therefore, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . In addition, it is easy to hold the temperature sensor  70  in the coil assembly  33 . 
     Further, according to the present embodiment, the inverter unit  8  is located on the rear side (−X side) of the motor housing  81 . Therefore, the rear portion of the motor housing  81  is covered with the inverter unit  8 , and the temperature inside the motor housing  81  is hardly released from the rear portion of the motor housing  81 . As a result, heat is easily confined in the rear portion in the motor housing  81 . Therefore, the rear portion of the coil assembly  33  housed in the motor housing  81  is likely to have a higher temperature. Therefore, in the rear portion of the coil  31 , a portion located below the terminal portions  34 U,  34 V, and  34 W and above the lower portion immersed in the oil O tends to be a portion having the highest temperature in the coil  31 . As a result, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     The portion in the motor housing  81  between the shaft  21  and the inverter unit  8  in the front-rear direction is substantially the center of the motor housing  81  in the vertical direction. Therefore, heat is particularly easily confined in a portion between the shaft  21  and the inverter unit  8  in the front-rear direction in the motor housing  81 . As a result, a portion of the coil  31  located between the shaft  21  and the inverter unit  8  in the front-rear direction tends to be a portion having the highest temperature in the coil  31 . To take a measure for this, according to the present embodiment, the temperature sensor  70  is located between the shaft  21  and the inverter unit  8  in the front-rear direction. Therefore, the temperature sensor  70  can more easily detect the temperature of the portion having the highest temperature in the coil  31 . Therefore, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     In addition, when the temperature sensor  70  is located between the shaft  21  and the inverter unit  8  in the front-rear direction, the distance between the temperature sensor  70  and the terminal portions  34 U,  34 V, and  34 W tends to be short. The coil lead wires are likely to concentrate around the terminal portions  34 U,  34 V, and  34 W, and heat generation is likely to increase. Therefore, since the temperature sensor  70  can be disposed at a position close to the terminal portions  34 U,  34 V, and  34 W, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     According to the present embodiment, the first busbar  100  and the terminal block  110  are provided in a portion located between the stator  30  and the inverter unit  8  in the front-rear direction in the motor housing  81 . 
     Therefore, the oil O supplied from the upper side to the stator  30  is easily blocked by the terminal block  110  and the first busbar  100 , and the oil O hardly flows to the lower side of the first busbar  100  and the terminal block  110 . As a result, the temperature of the portion of the coil  31  located below the first busbar  100  and the terminal block  110  is likely to be the highest temperature of the coil  31 . To take a measure for this, in the present embodiment, the temperature sensor  70  is located below the terminal block  110  and the first busbar  100 . Therefore, the temperature sensor  70  can more easily detect the temperature of the portion having the highest temperature in the coil  31 . Therefore, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     According to the present embodiment, the third flow passage  92   c  as a supply oil passage supplies the oil O to the portion of the second reservoir  10  located on the front side (+X side) of the motor axis J 1 . That is, the third flow passage  92   c  supplies the oil O to a portion of the second reservoir  10  located on the side opposite to the side where the terminal portions  34 U,  34 V, and  34 W are provided with respect to the motor axis J 1 . Therefore, the oil O is less likely to be supplied to the portion of the coil  31  located on the rear side (−X side) with respect to the motor axis J 1 . As a result, a portion located below the terminal portions  34 U,  34 V, and  34 W in the rear portion of the coil  31  is likely to be a portion having the highest temperature in the coil  31 . Therefore, the temperature sensor  70  can more accurately detect the highest temperature among the temperatures of the motor  2 . 
     In addition, according to the present embodiment, the plurality of temperature sensors  70  is provided in the portion of the coil assembly  33  located behind the motor axis J 1 , and is located below the terminal portions  34 U,  34 V, and  34 W and above the lower end of the rotor  20 . Therefore, the plurality of temperature sensors  70  can more suitably and accurately detect the highest temperature among the temperatures of the motor  2 . As a result, the control of the drive device  1  by the control unit  8   b  can be more suitably performed. 
     In the present embodiment, the control unit  8   b  adopts, for example, a detection result of the temperature sensor  70  that has detected a high temperature among the first temperature sensor  71  and the second temperature sensor  72 . In the present embodiment, the control unit  8   b  uses the higher value of the detection results of the first temperature sensor  71  and the second temperature sensor  72  when controlling the flow rate of the oil O. According to this, the maximum temperature of the motor  2  can be obtained with higher accuracy, and the drive device  1  can be suitably controlled based on the temperature of the motor  2  obtained with higher accuracy. In addition, for example, even when a failure occurs in one of the first temperature sensor  71  and the second temperature sensor  72 , the control of the drive device  1  can be suitably continued by using the other of the first temperature sensor  71  and the second temperature sensor  72 . 
     The present invention is not limited to the above-described embodiment, and other structures may be employed. In the first modification illustrated in  FIG. 11 , the drive device  1  includes a pipe  10   a  instead of the second reservoir. The pipe  10   a  has a tubular shape extending in one direction, and unlike the second reservoir, the upper side is not opened. An injection hole  10   d  opened toward the stator  30  is formed in the pipe  10   a . The pipe  10   a  is housed and fixed in the motor housing  81 . 
     The drive device  1  is provided with, as the pipe  10   a , a first pipe  10   b  disposed above the stator  30  and a second pipe  10   c  disposed on the front side of the stator  30 . Each pipe  10   a  extends in the left-right direction (Y axis direction), and has a right end opened and a left end closed. Each of the pipes  10   a  is connected to the third flow passage  92   c  at the right end on the upstream side. In the third flow passage  92   c , a channel connected to the cooler  97  on the upstream side is branched on the downstream side, and the branched channels are connected to the first pipe  10   b  and the second pipe  10   c , respectively. The oil O is supplied from the third flow passage  92   c  to each pipe  10   a , then flows leftward in the pipe  10   a , and is injected from each injection hole  10   d  to the stator  30 . 
     The first pipe  10   b  is disposed above the terminal portions  34 U,  34 V, and  34 W. More specifically, the opening of the injection hole  10   d  of the first pipe  10   b  is located above at least a part of the terminal portions  34 U,  34 V, and  34 W. In the circumferential direction, the first pipe  10   b  is disposed on the side opposite to the sensor with respect to the terminal portions  34 U,  34 V, and  34 W. 
     A plurality of injection holes  10   d  is formed in each pipe  10   a . The injection hole  10   d  of the first pipe  10   b  opens toward the stator core  32  and the coil ends  33   a  and  33   b . At least one of the injection holes  10   d  opening toward the coil end  33   b  of the first pipe  10   b  also opens to the terminal portions  34 U,  34 V, and  34 W. The injection hole  10   d  of the second pipe  10   c  opens only toward the stator  33  and does not open to the coil ends  33   a  and  33   b.    
     In the first modification, the oil O is injected in the opening direction of the injection hole  10   d  regardless of the inclination angle of the drive device  1 . Therefore, even when the drive device  1  is inclined, the oil O is easily injected to a desired place in the stator  32 . According to this, it is possible to suppress the oil O from being injected to an unintended place at the time of inclination of the drive device  1 , and it is possible to improve the cooling efficiency of the stator  30 . 
     In a second modification illustrated in  FIG. 12 , temperature sensors  73  and  74  are provided in addition to the temperature sensors  71  and  72 . Similarly to the present embodiment, the temperature sensors  71  and  72  are provided on one side of the coil assembly  33  in a predetermined direction orthogonal to both the axial direction and the vertical direction with respect to the motor axis J 1 . To take a measure for this, the temperature sensors  73  and  74  are provided on the other side of the coil assembly  33  in the predetermined direction with respect to the motor axis J 1 , that is, on the side opposite to the temperature sensors  71  and  72 . In this example, in the coil end  33   b , the temperature sensors  71  and  72  are provided on the rear side with respect to the motor axis J 1 , and the temperature sensors  73  and  74  are provided on the front side with respect to the motor axis J 1 . The first pipe  10   a  is disposed on the rear side with respect to the motor axis J 1 . In the second modification, similarly to the first modification, the injection hole of the second pipe  10   c  is not opened in the coil end  33   b . The four temperature sensors  70  are connected to the control unit  8   b , and detection results are sent to the control unit  8   b . The control unit  8   b  controls the flow rate sent by the oil pump  96  based on the highest value among the detection results of the four temperature sensors  70 . 
     Depending on the inclination angle of the drive device  1 , the supply position and the supply direction of the oil O from the reservoir or the pipe to the stator  30 , it may be difficult to supply the oil O to both sides of the stator  30  in the front-rear direction. In the configuration of the second modification in which the first pipe  10   b  is disposed on the rear side with respect to the motor axis J 1 , the oil O is hardly supplied to the front portion of the coil end  33   b . For this configuration in the second modification, since the temperature sensors  73  and  74  are also disposed on the front side, the temperatures on both sides in the front-rear direction of the coil end  33   b  can be measured. Therefore, even when the front side of the coil end  33   b  has higher temperature than the rear side, the maximum temperature of the motor  2  can be obtained with higher accuracy, and the drive device  1  can be suitably controlled based on the temperature of the motor  2  obtained with higher accuracy. 
     In the present embodiment, an example in which a plurality of temperature sensors is provided at one coil end has been described, but the present invention is not limited thereto. A configuration in which a temperature sensor is provided in each of both coil ends can also be adopted. The temperature sensor may be provided at any place as long as the temperature sensor is provided at a portion of the coil assembly located behind the motor axis, and is located below the terminal portion and above the lower end of the rotor. The temperature sensor may be provided on a coil lead wire of the coil assembly. The plurality of temperature sensors may be provided at different positions in the vertical direction. The plurality of temperature sensors may be different types of temperature sensors. The number of temperature sensors may be one or three or more. 
     Features as described above in the present specification may be combined appropriately as long as no conflict arises. 
     Features of the above-described preferred embodiments and the modifications thereof may be combined appropriately as long as no conflict arises. 
     While preferred embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.