Patent Publication Number: US-2022216820-A1

Title: Drive device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a U.S. national stage of application No. PCT/JP2020/016852, filed on Apr. 17, 2020, and priority under 35 U.S.C. § 119(a) and 35 U.S.C. § 365(b) is claimed from Japanese Patent Application No. 2019-080342, filed on Apr. 19, 2019; the entire disclosures of which are hereby incorporated herein by reference. 
    
    
     1. FIELD OF THE INVENTION 
     The present disclosure relates to a drive device. 
     2. BACKGROUND 
     A drive device mounted on a vehicle and accommodating oil in a case is known. For example, a drive device for a hybrid vehicle is known. 
     In the drive device as described above, there is a case where the oil accommodated in the case is used as lubricating oil for the deceleration device or the like in the drive device. In general, the lower the temperature is, the higher the viscosity of oil becomes. Therefore, the viscosity of oil becomes too high under a relatively low temperature environment, and the oil sometimes becomes less likely to function as lubricating oil for a deceleration device or the like. Therefore, there is a possibility that a failure occurs in the drive device. 
     SUMMARY 
     An example embodiment of a drive device of the present disclosure is a drive device that rotates an axle of a vehicle. The drive device includes a motor, a transmission that includes a decelerator connected to the motor and a differential connected to the motor via the decelerator, a housing that accommodates all of the motor, the decelerator, and the differential, a temperature sensor to detect a temperature of the motor, and a controller to control the motor. Oil supplied to the transmission is accommodated in the housing. The controller limits output of the motor based on a detection result of the temperature sensor. 
     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 example embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view showing a functional configuration of a vehicle drive system according to a first example embodiment of the present disclosure. 
         FIG. 2  is an overall configuration view schematically showing the drive device of the first example embodiment. 
         FIG. 3  is a flowchart showing an example of a control procedure by the controller of the first example embodiment. 
         FIG. 4  is a flowchart showing a procedure of operation check of the oil pump by the controller of the first example embodiment. 
         FIG. 5  is a flowchart showing a procedure of flow rate control of the oil pump by the controller of the first example embodiment. 
         FIG. 6  is a graph showing an example of a change in a duty ratio with respect to a temperature of a motor in the first example embodiment. 
         FIG. 7  is a flowchart showing a procedure of after-run control by the controller of the first example embodiment. 
         FIG. 8  is a flowchart showing a procedure of flow rate control of the oil pump by the controller of a second example embodiment of the present disclosure. 
         FIG. 9  is a graph showing an example of a change in a duty ratio with respect to a temperature of a motor in the second example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     A vehicle drive system  100  shown in  FIG. 1  is mounted on a vehicle and drives the vehicle. A vehicle equipped with the vehicle drive system  100  of the present example embodiment is a motor-powered vehicle, such as a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHV), and an electric vehicle (EV). The vehicle drive system  100  includes a drive device  1 , a radiator  110 , a refrigerant pump  120 , a fan device  130 , and a vehicle control device  140 . That is, the drive device  1 , the radiator  110 , the refrigerant pump  120 , the fan device  130 , and the vehicle control device  140  are provided in the vehicle. The radiator  110  cools a refrigerant W. In the present example embodiment, the refrigerant W is, for example, water. 
     The refrigerant pump  120  is an electricity-driven electric pump. The refrigerant pump  120  sends the refrigerant W from the radiator  110  to the drive device  1  via a refrigerant flow path  150 . The refrigerant flow path  150  is a flow path that extends from the radiator  110  to the drive device  1  and returns to the radiator  110  again. The refrigerant flow path  150  passes through the inside of an inverter unit  8  described later and the inside of an oil cooler  97 . The refrigerant W flowing through the refrigerant flow path  150  cools a controller  70  described later provided in the inverter unit  8  and an oil O flowing through the oil cooler  97 . 
     The fan device  130  can blow air to the radiator  110 . Accordingly, the fan device  130  can cool the radiator  110 . The type of the fan device  130  is not particularly limited as long as it can blow air to the radiator  110 . The fan device  130  may be an axial fan, a centrifugal fan, or a blower. 
     The fan device  130  is switched between in a driving state and in a stopping state according to the temperature of the refrigerant W accommodated in the radiator  110 , for example. For example, when the vehicle is traveling, a flow of air generated by the traveling of the vehicle is blown to the radiator  110 , and the refrigerant W in the radiator  110  is easily cooled. In this case, the fan device  130  is in a stopping state, for example. On the other hand, when the vehicle is stopped, the flow of air as described above is less likely to occur, and hence the refrigerant W inside the radiator  110  can be suitably cooled by blowing air to the radiator  110  with the fan device  130  being in the driving state. Note that the fan device  130  may be constantly in the driving state regardless of the travel state of the vehicle. 
     The vehicle control device  140  controls each device mounted on the vehicle. In the present example embodiment, the vehicle control device  140  controls the drive device  1 , the refrigerant pump  120 , and the fan device  130 . A signal from an ignition switch IGS provided in the vehicle is input to the vehicle control device  140 . The ignition switch IGS is a switch that switches driving and stopping of the drive device  1 , and is directly or indirectly operated by the driver who drives the vehicle. 
     When the ignition switch IGS is switched from OFF to ON, the vehicle control device  140  sends a signal to the controller  70  described later of the drive device  1  to drive the drive device  1  and bring the vehicle into a travelable state. On the other hand, when the ignition switch IGS is turned from ON to OFF, the vehicle control device  140  sends a signal to the controller  70  to stop the drive device  1 . 
     The drive device  1  is used as a power source of a motor-powered vehicle such as a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV) described above. As shown in  FIG. 2 , the drive device  1  includes a motor  2 , a transmission device  3  having a deceleration device  4  and a differential device  5 , a housing  6 , the inverter unit  8 , an oil pump  96 , and the oil cooler  97 . The housing  6  accommodates therein the motor  2  and the transmission device  3 . The housing  6  has a motor accommodation portion  81  accommodating the motor  2  therein, and a gear accommodation portion  82  accommodating the deceleration device  4  and the differential device  5  therein. 
     In the present example embodiment, the motor  2  is an inner rotor motor. The motor  2  has a rotor  20 , a stator  30 , and bearings  26  and  27 . The rotor  20  is rotatable about a motor axis J 1  extending in the horizontal direction. The rotor  20  has a shaft  21  and a rotor body  24 . Although not illustrated, the rotor body  24  has a rotor core and a rotor magnet fixed to the rotor core. Torque of the rotor  20  is transmitted to the deceleration device  4 . 
     In the following description, the horizontal direction in which the motor axis J 1  extends is referred to as an “axial direction” (axially), the radial direction about the motor axis J 1  is simply referred to as a “radial direction” (radially), and the circumferential direction about the motor axis J 1 , i.e., around the axis of the motor axis J 1  is simply referred to as a “circumferential direction” (circumferentially). In the present example embodiment, the axial direction is the right-left direction in  FIG. 2 , for example, and is the right-left direction of the vehicle, i.e., the vehicle width direction. In the following description, the right side in  FIG. 2  in the axial direction is simply referred to as a “right side”, and the left side in  FIG. 2  in the axial direction is simply referred to as a “left side”. In addition, the up-down direction in  FIG. 2  is referred to as a vertical direction. The upper side in  FIG. 2  is simply referred to as an “up” (upside, upper, upper side, upward) as the vertical direction upper side, and the lower side in  FIG. 2  is simply referred to as a “down” (downside, lower, lower side, downward) as the vertical direction lower side. 
     The shaft  21  extends along the axial direction about the motor axis J 1 . The shaft  21  rotates about the motor axis J 1 . The shaft  21  is a hollow shaft provided with a hollow portion  22  inside. The shaft  21  is provided with a communication hole  23 . The communication hole  23  extends in the radial direction and connects the hollow portion  22  with the outside of the shaft  21 . 
     The shaft  21  extends across the motor accommodation portion  81  and the gear accommodation portion  82  of the housing  6 . The left end of the shaft  21  projects into the gear accommodation portion  82 . A first gear  41  described later of the deceleration device  4  is fixed to the left end of the shaft  21 . The shaft  21  is rotatably supported by the bearings  26  and  27 . 
     The stator  30  is opposed to the rotor  20  in the radial direction across a gap. More specifically, the stator  30  is positioned radially outside the rotor  20 . The stator  30  has a stator core  32  and a coil assembly  33 . The stator core  32  is fixed to the inner peripheral surface of the motor accommodation portion  81 . Although not illustrated, the stator core  32  has an axially extending cylindrical core back and a plurality of teeth extending radially inside from the core back. 
     The coil assembly  33  has a plurality of coils  31  attached to the stator core  32  along the circumferential direction. The plurality of coils  31  are attached to the respective teeth of the stator core  32  with an insulator (not illustrated) interposed therebetween. The plurality of coils  31  are arranged along the circumferential direction. More specifically, the plurality of coils  31  are arranged at equal intervals along the circumferential direction throughout the circumference. Although not illustrated, the coil assembly  33  may have a binding member or the like for binding the coils  31 , or may have a connecting wire for connecting the coils  31  with one another. 
     The coil assembly  33  has coil ends  33   a  and  33   b  projecting axially from the stator core  32 . The coil end  33   a  is a part projecting to the right side from the stator core  32 . The coil end  33   b  is a part projecting to the left side from the stator core  32 . The coil end  33   a  includes a part projects to the right side relative to the stator core  32  of each coil  31  included in the coil assembly  33 . The coil end  33   b  includes a part projects to the left side relative to the stator core  32  of each coil  31  included in the coil assembly  33 . In the present example embodiment, the coil ends  33   a  and  33   b  are annular about the motor axis J 1 . Although not illustrated, the coil ends  33   a  and  33   b  may include binding members or the like for binding the coils  31 , or may include connecting wires for connecting the coils  31  with one another. 
     The bearings  26  and  27  rotatably support the rotor  20 . The bearings  26  and  27  are, for example, ball bearings. The bearing  26  is a bearing rotatably supporting a part of the rotor  20  positioned on the right side relative to the stator core  32 . In the present example embodiment, the bearing  26  supports a part of the shaft  21  positioned on the right side relative to the part to which the rotor body  24  is fixed. The bearing  26  is held by a wall portion covering the right side of the rotor  20  and the stator  30  in the motor accommodation portion  81 . 
     The bearing  27  is a bearing rotatably supporting a part of the rotor  20  positioned on the left side relative to the stator core  32 . In the present example embodiment, the bearing  27  supports a part of the shaft  21  positioned on the left side relative to the part to which the rotor body  24  is fixed. The bearing  27  is held in a partition wall  61   c  described later. 
     As shown in  FIG. 1 , the motor  2  has a temperature sensor  71  detectable of the temperature of the motor  2 . That is, the drive device  1  includes the temperature sensor  71 . In the present example embodiment, the temperature of the motor  2  is, for example, the temperature of the coil  31  of the motor  2 . Although not illustrated, the temperature sensor  71  is embedded in, for example, the coil end  33   a  or the coil end  33   b . The type of the temperature sensor  71  is not particularly limited. The detection result of the temperature sensor  71  is sent to the controller  70  described later. 
     The deceleration device  4  is connected to the motor  2 . More specifically, as shown in  FIG. 2 , the deceleration device  4  is connected to the left end of the shaft  21 . The deceleration device  4  reduces the rotational speed of the motor  2  and increases the torque output from the motor  2  according to the reduction ratio. The deceleration device  4  transmits torque outputted from the motor  2  to the differential device  5 . The deceleration device  4  has a first gear  41 , a second gear  42 , a third gear  43 , and an intermediate shaft  45 . 
     The first gear  41  is fixed to the outer peripheral surface at the left end of the shaft  21 . The first gear  41 , together with the shaft  21 , rotates about the motor axis J 1 . The intermediate shaft  45  extends along an intermediate axis J 2 . In the present example embodiment, the intermediate axis J 2  is parallel to the motor axis J 1 . The intermediate shaft  45  rotates about the intermediate axis J 2 . 
     The second gear  42  and the third gear  43  are fixed to the outer peripheral surface of the intermediate shaft  45 . The second gear  42  and the third gear  43  are connected via the intermediate shaft  45 . The second gear  42  and the third gear  43  rotate about the intermediate axis J 2 . The second gear  42  meshes with the first gear  41 . The third gear  43  meshes with a ring gear  51  described later of the differential device  5 . The outer diameter of the second gear  42  is larger than the outer diameter of the third gear  43 . In the present example embodiment, the lower end of the second gear  42  is the lowermost part of the deceleration device  4 . 
     The torque output from the motor  2  is transmitted to the differential device  5  via the deceleration device  4 . More specifically, the torque output from the motor  2  is transmitted to the ring gear  51  of the differential device  5  via the shaft  21 , the first gear  41 , the second gear  42 , the intermediate shaft  45 , and the third gear  43  in this order. The gear ratio of each gear, the number of gears, and the like can be variously changed according to the required reduction ratio. In the present example embodiment, the deceleration device  4  is a parallel axis gear type deceleration device in which the axis centers of the gears are disposed in parallel. 
     The differential device  5  is connected to the deceleration device  4 . Thus, the differential device  5  is connected to the motor  2  via the deceleration device  4 . The differential device  5  is a device for transmitting the torque output from the motor  2  to the wheels of the vehicle. The differential device  5  transmits the same torque to axles  55  of the right and left wheels while absorbing the speed difference between the right and left wheels when the vehicle turns. The differential device  5  rotates the axle  55  about a differential axis J 3 . Thus, the drive device  1  rotates the axle  55  of the vehicle. The differential axis J 3  extends in the right-left direction of the vehicle, i.e., the vehicle width direction of the vehicle. In the present example embodiment, the differential axis J 3  is parallel to the motor axis J 1 . 
     The differential device  5  includes a ring gear  51 , a gear housing not illustrated, a pair of pinion gears not illustrated, a pinion shaft not illustrated, and a pair of side gears not illustrated. The ring gear  51  is a gear rotating about the differential axis J 3 . The ring gear  51  meshes with the third gear  43 . Thus, the torque output from the motor  2  is transmitted to the ring gear  51  via the deceleration device  4 . The lower end of the ring gear  51  is positioned lower than the deceleration device  4 . In the present example embodiment, the lower end of the ring gear  51  is the lowermost part of the differential device  5 . 
     The housing  6  is an outer casing of the drive device  1 . The housing  6  has a partition wall  61   c  axially partitioning the inside of the motor accommodation portion  81  and the inside of the gear accommodation portion  82 . The partition wall  61   c  is provided with a partition wall opening  68 . The inside of the motor accommodation portion  81  and the inside of the gear accommodation portion  82  are connected to each other via the partition wall opening  68 . 
     The oil O is accommodated in the housing  6 . More specifically, the oil O is accommodated inside the motor accommodation portion  81  and inside the gear accommodation portion  82 . A lower region inside the gear accommodation portion  82  is provided with an oil sump P for accumulating the oil O. An oil surface S of the oil sump P is positioned upper than the lower end of the ring gear  51 . Thus, the lower end of the ring gear  51  is immersed in the oil O in the gear accommodation portion  82 . The oil surface S of the oil sump P is positioned lower than the differential axis J 3  and the axle  55 . 
     The oil O in the oil sump P is sent to the inside of the motor accommodation portion  81  through an oil passage  90  described later. The oil O sent to the inside of the motor accommodation portion  81  accumulates in a lower region inside the motor accommodation portion  81 . At least a part of the oil O accumulated in the motor accommodation portion  81  moves to the gear accommodation portion  82  through the partition wall opening  68  and returns to the oil sump P. 
     Note that when “the oil is accommodated in a certain part” in the present specification, the oil is only required to be positioned in a certain part at least in a part when the motor is being driven, and the oil may not be positioned in a certain part when the motor is stopped. For example, when the oil O is accommodated in the motor accommodation portion  81  in the present example embodiment, the oil O is only required to be positioned in the motor accommodation portion  81  at least in part when the motor  2  is being driven, and the oil O in the motor accommodation portion  81  may entirely be moved to the gear accommodation portion  82  through the partition wall opening  68  when the motor  2  is stopped. A part of the oil O sent to the inside of the motor accommodation portion  81  through the oil passage  90  described later may remain inside the motor accommodation portion  81  in a state where the motor  2  is stopped. 
     In the present description, when “the lower end of the ring gear is immersed in the oil in the gear accommodation portion”, the lower end of the ring gear is only required to be immersed in the oil in the gear accommodation portion at least in part when the motor is being driven, and the lower end of the ring gear may not be immersed in the oil in the gear accommodation portion in part when the motor is being driven or the motor is stopped. For example, as a result of the oil O in the oil sump P being sent to the inside of the motor accommodation portion  81  due to the oil passage  90  described later, the oil surface S of the oil sump P may be lowered, and the lower end of the ring gear  51  may be temporarily not immersed in the oil O. 
     The oil O circulates in the oil passage  90  described later. The oil O is used for lubrication of the deceleration device  4  and the differential device  5 . The oil O is used for cooling the motor  2 . As the oil O, an oil equivalent to an automatic transmission fluid (ATF) having a relatively low viscosity is preferably used in order to perform the function of lubricating oil and cooling oil. 
     A bottom portion  82   a  of the gear accommodation portion is positioned lower than a bottom portion  81   a  of the motor accommodation portion  81 . Therefore, the oil O sent from the inside of the gear accommodation portion  82  into the motor accommodation portion  81  easily flows into the gear accommodation portion  82  through the partition wall opening  68 . 
     The drive device  1  is provided with the oil passage  90  for circulating the oil O inside the housing  6 . The oil passage  90  is a path for supplying the oil O from the oil sump P to the motor  2  and guiding the oil O to the oil sump P again. The oil passage  90  is provided across the inside of the motor accommodation portion  81  and the inside of the gear accommodation portion  82 . 
     In this description, the term “oil passage” means a path of oil. Therefore, the term “oil passage” is a concept including not only a “flow path” that creates a steady unidirectional flow of oil, but also a path for temporarily retaining oil and a path for oil to drip off. The path for temporarily retaining oil includes, for example, a reservoir for storing the oil. 
     The oil passage  90  has a first oil passage  91  and a second oil passage  92 . The first oil passage  91  and the second oil passage  92  each circulate the oil O inside the housing  6 . The first oil passage  91  has a scoop path  91   a , a shaft supply path  91   b , an in-shaft path  91   c , and an in-rotor path  91   d . A first reservoir  93  is provided in the path of the first oil passage  91 . The first reservoir  93  is provided in the gear accommodation portion  82 . 
     The scoop path  91   a  is a path for scooping the oil O from the oil sump P by rotation of the ring gear  51  of the differential device  5  and receiving the oil O in the first reservoir  93 . The first reservoir  93  opens upward. The first reservoir  93  receives the oil O scooped by the ring gear  51 . When the liquid level of the oil sump P is high immediately after the motor  2  is driven, the first reservoir  93  also receives the oil O scooped by the second gear  42  and the third gear  43  in addition to the ring gear  51 . 
     The oil O scooped by the ring gear  51  is also supplied to the deceleration device  4  and the differential device  5 . Thus, the oil O accommodated in the housing  6  is supplied to the transmission device  3 . The oil O supplied to the transmission device  3  is supplied as lubricating oil to the gear of the deceleration device  4  and the gear of the differential device  5 . The oil O scooped by the ring gear  51  may be supplied to either the deceleration device  4  or the differential device  5 . 
     The shaft supply path  91   b  guides the oil O from the first reservoir  93  to the hollow portion  22  of the shaft  21 . The in-shaft path  91   c  is a path for the oil O to pass through the hollow portion  22  of the shaft  21 . The in-rotor path  91   d  is a path passing through the inside of the rotor body  24  from the communication hole  23  of the shaft  21  and scatters to the stator  30 . 
     In the in-shaft path  91   c , centrifugal force is applied to the oil O inside the rotor  20  due to the rotation of the rotor  20 . Thus, the oil O is continuously scattered radially outward from the rotor  20 . With the scattering of the oil O, the path inside the rotor  20  becomes negative pressure, the oil O accumulated in the first reservoir  93  is sucked into the rotor  20 , and the path inside the rotor  20  is filled with the oil O. 
     The oil O having reached the stator  30  absorbs heat from the stator  30 . The oil O having cooled the stator  30  is drips to the lower side and accumulated in the lower region in the motor accommodation portion  81 . The oil O accumulated in the lower region in the motor accommodation portion  81  moves to the gear accommodation portion  82  through the partition wall opening  68  provided in the partition wall  61   c . As described above, the first oil passage  91  supplies the oil O to the rotor  20  and the stator  30 . 
     In the second oil passage  92 , the oil O is lifted up from the oil sump P to the upper side of the stator  30  and supplied to the stator  30 . That is, the second oil passage  92  supplies the oil O from the upper side of the stator  30  to the stator  30 . The second oil passage  92  is provided with the oil pump  96 , the oil cooler  97 , and a second reservoir  10 . The second oil passage  92  has a first flow path  92   a , a second flow path  92   b , and a third flow path  92   c.    
     The first flow path  92   a , the second flow path  92   b , and the third flow path  92   c  are provided on the wall portion of the housing  6 . The first flow path  92   a  connects the oil sump P and the oil pump  96 . The second flow path  92   b  connects the oil pump  96  and the oil cooler  97 . The third flow path  92   c  extends upward from the oil cooler  97 . The third flow path  92   c  is provided in the wall portion of the motor accommodation portion  81 . Although not illustrated, the third flow path  92   c  has a supply port opening inside the motor accommodation portion  81  above the stator  30 . The supply port supplies the oil O to the inside of the motor accommodation portion  81 . 
     The oil pump  96  is an electric pump driven by electricity. The oil pump  96  sends the oil O accommodated in the housing  6  to the motor  2 . In the present example embodiment, the oil pump  96  sucks up the oil O from the oil sump P via the first flow path  92   a , and supplies the oil O to the motor  2  via the second flow path  92   b , the oil cooler  97 , the third flow path  92   c , and the second reservoir  10 . As shown in  FIG. 1 , the oil pump  96  has a motor unit  96   a , a pump unit  96   b , and a rotation sensor  72 . The pump unit  96   b  is rotated by the motor unit  96   a . Although not illustrated, the pump unit  96   b  has an inner rotor connected to the motor unit  96   a  and an outer rotor surrounding the inner rotor. The oil pump  96  sends the oil O to the motor  2  by rotating the pump unit  96   b  by the motor unit  96   a.    
     The rotation sensor  72  can detect the rotation of the pump unit  96   b . In the present example embodiment, by detecting the rotation of the motor unit  96   a , the rotation sensor  72  can detect the rotation of the pump unit  96   b  rotated by the motor unit  96   a . The type of the rotation sensor  72  is not particularly limited as long as the rotation of the pump unit  96   b  can be detected. The rotation sensor  72  may be a magnetic sensor, may be a resolver, or may be an optical sensor. If the rotation sensor  72  is a magnetic sensor, the rotation sensor  72  may be a Hall element such as a Hall IC or may be a magnetoresistive element. The rotation sensor  72  may directly detect the rotation of the pump unit  96   b . The detection result of the rotation sensor  72  is sent to the controller  70  described later. 
     As shown in  FIG. 2 , the oil cooler  97  cools the oil O passing through the second oil passage  92 . The second flow path  92   b  and the third flow path  92   c  are connected to the oil cooler  97 . The second flow path  92   b  and the third flow path  92   c  are connected via an internal flow path of the oil cooler  97 . As shown in  FIG. 1 , the refrigerant W cooled by the radiator  110  is supplied to the oil cooler  97  by the refrigerant pump  120  through the refrigerant flow path  150 . The oil O passing through the inside of the oil cooler  97  is cooled by heat exchange with the refrigerant W passing through the refrigerant flow path  150 . The oil O cooled by the oil cooler  97  is the oil O sent by the oil pump  96 . That is, the refrigerant W sent from the refrigerant pump  120  cools the oil O sent by the oil pump  96  in the oil cooler  97 . 
     As shown in  FIG. 2 , the second reservoir  10  constitutes a part of the second oil passage  92 . The second reservoir  10  is positioned inside the motor accommodation portion  81 . The second reservoir  10  is positioned above the stator  30 . The second reservoir  10  is supported from below by the stator  30 , and is provided in the motor  2 . The second reservoir  10  is made of, for example, a resin material. 
     In the present example embodiment, the second reservoir is in the shape of an upward opening gutter. The second reservoir  10  stores the oil O. In the present example embodiment, the second reservoir  10  stores the oil O supplied into the motor accommodation portion  81  via the third flow path  92   c . The second reservoir  10  has a supply port  10   a  for supplying the oil O to the coil ends  33   a  and  33   b . Thus, the oil O stored in the second reservoir  10  can be supplied to the stator  30 . 
     The oil O supplied from the second reservoir  10  to the stator  30  drips to the lower side and accommodated in the lower region in the motor accommodation portion  81 . The oil O accumulated in the lower region in the motor accommodation portion  81  moves to the gear accommodation portion  82  through the partition wall opening  68  provided in the partition wall  61   c . As described above, the second oil passage  92  supplies the oil O to the stator  30 . 
     As shown in  FIG. 1 , the inverter unit  8  has the controller  70 . That is, the drive device  1  includes the controller  70 . The controller  70  is accommodated in an inverter case  8   a . The controller  70  is cooled by the refrigerant W flowing in a part of the refrigerant flow path  150  provided in the inverter case  8   a . The controller  70  controls the motor  2  and the motor unit  96   a  of the oil pump  96 . Although not illustrated, the controller  70  has an inverter circuit for adjusting power supplied to the motor  2 . In the present example embodiment, the controller  70  performs control according to steps S 1  to S 6  shown in  FIG. 3 . 
     When the ignition switch IGS of the vehicle is turned on in step S 1 , the controller  70  performs step S 2 . In step S 2 , the controller  70  checks the operation of the oil pump  96 . As shown in  FIG. 4 , in the present example embodiment, the operation check by the oil pump  96  in step S 2  includes steps S 2   a  to S 2   d.    
     In step S 2   a , the controller  70  drives the oil pump  96  for a first predetermined time. The first predetermined time is, for example, 5 seconds or more and 15 seconds or less. In step S 2   b , the controller  70  determines whether or not the oil pump  96  is operating normally. Specifically, the controller  70  acquires, based on the rotation sensor  72 , the rotational speed of the pump unit  96   b  when the oil pump  96  is driven for the first predetermined time, and determines whether or not the rotational speed of the pump unit  96   b  is within a predetermined range. The predetermined range is a range, for example, within about ±10% of the target rotational speed sent from the controller  70  to the oil pump  96  as a command. That is, the predetermined range is a range of the rotational speed of the pump unit  96   b  that is allowed when a predetermined target rotational speed is input to the oil pump  96 , for example. 
     If the rotational speed of the pump unit  96   b  is within the predetermined range, the controller  70  determines that the oil pump  96  is operating normally, and performs step S 2   c . In step S 2   c , the controller  70  determines the travel mode of the vehicle to the normal travel mode. When the travel mode is determined to be the normal travel mode, the controller  70  performs step S 3 . In step S 3 , the controller  70  drives the oil pump  96  to being the vehicle into a travelable state. 
     On the other hand, in a case where the rotational speed of the pump unit  96   b  is out of the predetermined range, the controller  70  determines that the oil pump  96  is not operating normally, and performs step S 2   d . In step S 2   d , the controller  70  determines the travel mode of the vehicle to a limp home mode. The limp home mode is a mode in which the output of the motor  2  is limited. That is, in the present example embodiment, the controller  70  limits the output of the motor  2  when determining that the operation of the oil pump  96  is abnormal based on the detection result of the rotation sensor  72 . 
     The case where the rotational speed of the pump unit  96   b  is out of the predetermined range includes a case where the rotational speed of the pump unit  96   b  is smaller than the predetermined range and a case where the rotational speed of the pump unit  96   b  is larger than the predetermined range. That is, in the present example embodiment, when the rotational speed of the pump unit  96   b  when the oil pump  96  is driven for the first predetermined time is different from the target rotational speed input to the oil pump  96  by a predetermined rotational speed or more, the controller  70  determines that the operation of the oil pump  96  is abnormal and limits the output of the motor  2 . 
     Here, the predetermined rotational speed is a value equal to or larger than an error in the rotational speed of the pump unit  96   b  permitted with respect to the target rotational speed. The predetermined rotational speed is, for example, a value of 10% or more of the target rotational speed. That is, the controller limits the output of the motor  2 , for example, when the rotational speed of the pump unit  96   b  obtained based on the rotation sensor  72  is deviated by 10% or more from the target rotational speed. 
     In the present example embodiment, the output of the motor  2  limited based on the detection result of the rotation sensor  72  includes the rotational speed of the motor  2  and the torque of the motor  2 . By limiting the torque of the motor  2  and the rotational speed of the motor  2 , the speed and acceleration of the vehicle are limited. The limitation of the output of the motor  2  in the limp home mode is a limitation such that the temperature of the motor  2  does not rise even if the motor  2  is not cooled by the oil pump  96 . That is, in the limp home mode, the rotational speed and torque of the motor  2  are limited to relatively low values, and the speed and acceleration of the vehicle are limited to relatively low values. 
     When the travel mode is determined to be the limp home mode, the controller  70  brings the vehicle into a travelable state with the output of the motor  2  being limited. At this time, the controller  70  may keep the oil pump  96  not operating normally in a stopping state. In the limp home mode, the controller  70  continues to limit output of the motor  2  until the ignition switch IGS is turned off. 
     For example, when the oil pump  96  is not operating normally, there is a possibility that a failure occurs in the supply of the oil O to the motor  2  and the cooling of the motor  2  becomes insufficient. Therefore, the temperature of the motor  2  becomes excessively high, and there is a possibility that a failure occurs in the motor  2 . In contrast, according to the present example embodiment, as described above, the controller  70  limits output of the motor  2  based on the detection result of the rotation sensor  72 . Therefore, when the oil pump  96  is not operating normally, the output of the motor  2  can be limited. When the output of the motor  2  is limited, the heat generation amount in the motor  2  decreases. Thus, even if the oil pump  96  is not operating normally, the temperature of the motor  2  can be suppressed from rising, and the temperature of the motor  2  can be suppressed from becoming excessively high. Therefore, it is possible to suppress a failure from occurring in the motor  2 . Since the vehicle can travel while limiting the output of the motor  2 , the vehicle can move to a desired place while suppressing the damage of the motor  2 . 
     In the present example embodiment, the controller  70  limits the output of the motor  2  when determining that the operation of the oil pump  96  is abnormal based on the detection result of the rotation sensor  72 . Therefore, the output of the motor  2  can be suitably limited according to the operation state of the oil pump  96 . Therefore, it is possible to suitably suppress a failure from occurring in the motor  2 . 
     In the present example embodiment, the controller  70  determines that the operation of the oil pump  96  is abnormal and limits the output of the motor  2  when the rotational speed of the pump unit  96   b  when the oil pump  96  is driven for the first predetermined time is different from the target rotational speed input to the oil pump  96  by a predetermined rotational speed or more. Therefore, the controller  70  can easily determine that the operation of the oil pump  96  is abnormal based on the rotational speed of the pump unit  96   b , and can more suitably limit the output of the motor  2 . Therefore, it is possible to more suitably suppress a failure from occurring in the motor  2 . 
     According to the present example embodiment, the output of the motor  2  limited based on the detection result of the rotation sensor  72  includes the rotational speed of the motor  2 . Therefore, the rotational speed of the motor  2  can be limited relatively low, and the temperature rise of the motor  2  can be more suitably suppressed. 
     According to the present example embodiment, the output of the motor  2  limited based on the detection result of the rotation sensor  72  includes the torque of the motor  2 . Therefore, the torque of the motor  2  can be limited relatively low, and the temperature rise of the motor  2  can be more suitably suppressed. 
     When the rotational speed of the motor  2  is limited, the oil O is less likely to be scooped by the ring gear  51 , and the oil O as lubricating oil becomes less likely to be supplied to the transmission device  3 . Therefore, there is a risk that the gears in the transmission device  3  rub against each other and cause seizure. On the other hand, by limiting the torque of the motor  2 , it is possible to reduce the load applied between the gears of the transmission device  3 . Thus, even if the oil O as lubricating oil is not supplied, the gears are suppressed from rubbing against each other and causing seizure. 
     As described above, in the present example embodiment, in step S 2  immediately after the ignition switch IGS of the vehicle is turned on, the controller  70  checks the operation of the oil pump  96  and determines the travel mode of the vehicle. In other words, in the present example embodiment, the controller  70  determines whether or not to limit the output of the motor  2  immediately after the ignition switch IGS of the vehicle is turned on. Therefore, before the vehicle starts traveling, it is possible to detect the abnormality of the oil pump  96 , and it is possible to select the travel mode in which a failure can be suppressed from occurring in the motor  2 , i.e., the limp home mode in the present example embodiment. 
     In this description, “immediately after the ignition switch of the vehicle is turned on” includes a period from when the ignition switch is turned on until when the vehicle is brought into a travelable state. 
     As shown in  FIG. 3 , having determined the travel mode of the vehicle to be the normal travel mode, and having brought the vehicle into a travelable state in step S 3 , the controller  70  next performs step S 4 . In step S 4 , the controller  70  controls the flow rate of the oil pump  96  according to the temperature of the motor  2 . In the present example embodiment, step S 4  is constantly performed until the ignition switch IGS is turned off in step S 5  after the vehicle is brought into a travelable state. 
     In the present example embodiment, the controller  70  controls the oil pump  96  by pulse width modulation (PWM) control. By adjusting the duty ratio of the pulse current supplied to the oil pump  96 , the controller  70  controls the output of the oil pump  96  and controls the flow rate of the oil O sent by the oil pump  96 . The larger the duty ratio of the pulse current supplied to the oil pump  96  is, the larger the output of the oil pump  96  becomes, and the larger the flow rate of the oil O sent by the oil pump  96  becomes. The smaller the duty ratio of the pulse current supplied to the oil pump  96  is, the smaller the output of the oil pump  96  becomes, and the smaller the flow rate of the oil O sent by the oil pump  96  becomes. The flow rate of the oil O sent by the oil pump  96  is proportional to, for example, the duty ratio of the pulse current supplied to the oil pump  96 . 
     Here, for example, it has been required to more efficiently control the oil pump  96  from the viewpoint of reducing the power consumption of the drive device  1 , suitably cooling the motor  2 , and the like. On the other hand, according to the present example embodiment, the controller  70  is provided in the inverter unit  8 , and the detection result of the temperature sensor  71  is sent to the controller  70 . That is, the oil pump  96  can be directly controlled by the controller  70  to which the detection result of the temperature sensor  71  is sent. Therefore, for example, the responsiveness of control of the oil pump  96  based on the temperature of the motor  2  can be improved as compared with a case where the detection result of the temperature sensor  71  is sent from the controller  70  to the vehicle control device  140  and the control of the oil pump  96  is performed by the vehicle control device  140 . As a result, the oil pump  96  can be controlled more efficiently as compared with the case where the control of the oil pump  96  is performed by the vehicle control device  140 . Therefore, the power consumption of the drive device  1  can be reduced, and the motor  2  can be suitably cooled by the oil pump  96 . 
     The drive device  1  may include a flow rate sensor that can detect the flow rate of the oil O sent from the oil pump  96 . In this case, based on the detection result of the flow rate sensor, the controller  70  may adjust the output of the oil pump  96  and adjust the flow rate of the oil O sent from the oil pump  96  to a desired flow rate. 
     As shown in  FIG. 5 , the flow rate control of the oil pump  96  in step S 4  of the present example embodiment includes steps S 4   a  to S 4   e . In step S 4   a , the controller  70  determines an operation mode of the oil pump  96  based on the temperature of the motor  2 , and drives the oil pump  96  in the determined operation mode. Specifically, the controller  70  acquires the temperature of the motor  2  based on the temperature sensor  71 , and determines the operation mode of the oil pump  96  based on the temperature of the motor  2 . As shown in  FIG. 6 , in the present example embodiment, the operation mode of the oil pump  96  includes a first mode CM 1 , a second mode CM 2 , a third mode CM 3 , a first linear change mode LM 1 , and a second linear change mode LM 2 . 
     In the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is within a predetermined first temperature range TR 1 , the controller  70  sets the operation mode of the oil pump  96  to the first mode CM 1 . In the example of  FIG. 6 , the first temperature range TR 1  is a temperature range of 80° C. or lower. In the first mode CM 1 , the controller  70  sets the duty ratio of the pulse current sent to the oil pump  96 , for example, to a constant value DR 1 . When the duty ratio of the pulse current supplied to the oil pump  96  is the value DR 1 , the flow rate of the oil O sent by the oil pump  96  is a first flow rate, for example. The first flow rate is a predetermined flow rate as a flow rate of the oil O sent to the motor  2 , for example, when the vehicle travels in a normal state. 
     In the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is a temperature within a second temperature range TR 2 , the controller  70  sets the operation mode of the oil pump  96  to the second mode CM 2 . The second temperature range TR 2  is a temperature range in which the temperature is higher than that in the first temperature range TR 1 . The second temperature range TR 2  is narrower than the first temperature range TR 1 , for example. In the example of  FIG. 6 , the second temperature range TR 2  is a temperature range of 100° C. or more and 130° C. or less. 
     In the present example embodiment, the first temperature range TR 1  and the second temperature range TR 2  are provided at an interval with each other. In the present example embodiment, the difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  is 5° C. or more and 30° C. or less. More specifically, in the present example embodiment, the difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  is 10° C. or more and 20° C. or less. In the example of  FIG. 6 , the maximum temperature in the first temperature range TR 1  is 80° C., and the minimum temperature in the second temperature range TR 2  is 100° C. That is, in the example of  FIG. 6 , the difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  is 20° C. 
     In the second mode CM 2 , the controller  70  sets the duty ratio of the pulse current supplied to the oil pump  96 , for example, to a constant value DR 2 . The value DR 2  is a value higher than the value DR 1 . When the duty ratio of the pulse current supplied to the oil pump  96  is the value DR 2 , the flow rate of the oil O sent by the oil pump  96  is, for example, a second flow rate larger than the first flow rate. Thus, the output of the oil pump  96  in the second mode CM 2  is larger than the output of the oil pump  96  in the first mode CM 1 . 
     In the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is a temperature within a third temperature range TR 3 , the controller  70  sets the operation mode of the oil pump  96  to the third mode CM 3 . The third temperature range TR 3  is a temperature range in which the temperature is higher than that in the second temperature range TR 2 . The third temperature range TR 3  is, for example, wider than the second temperature range TR 2 . In the example of  FIG. 6 , the third temperature range TR 3  is a temperature range of 140° C. or higher. 
     In the present example embodiment, the second temperature range TR 2  and the third temperature range TR 3  are provided at an interval with each other. In the present example embodiment, the difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  is 5° C. or more and 30° C. or less. More specifically, in the present example embodiment, the difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  is 10° C. or more and 20° C. or less. In the example of  FIG. 6 , the maximum temperature in the second temperature range TR 2  is 130° C., and the minimum temperature in the third temperature range TR 3  is 140° C. That is, in the example of  FIG. 6 , the difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  is 10° C. 
     In the third mode CM 3 , the controller  70  sets the duty ratio of the pulse current supplied to the oil pump  96 , for example, to a constant value DR 3 . The value DR 3  is a value higher than the value DR 2 . The difference between the value DR 3  and the value DR 2  is, for example, smaller than the difference between the value DR 2  and the value DR 1 . When the duty ratio of the pulse current supplied to the oil pump  96  is the value DR 3 , the flow rate of the oil O sent by the oil pump  96  is, for example, a third flow rate larger than the second flow rate. As described above, the output of the oil pump  96  in the third mode CM 3  is larger than the output of the oil pump  96  in the second mode CM 2 . 
     As described above, according to the present example embodiment, the first mode CM 1 , the second mode CM 2 , and the third mode CM 3  are provided as the operation mode of the oil pump  96 , and the output of the oil pump  96  increases in the order of the first mode CM 1 , the second mode CM 2 , and the third mode CM 3 . The controller  70  sets the operation mode of the oil pump  96  to the first mode CM 1  when the temperature of the motor  2  is within the first temperature range TR 1 , sets the operation mode of the oil pump  96  to the second mode CM 2  when the temperature of the motor  2  is within the second temperature range TR 2  higher than the first temperature range TR 1 , and sets the operation mode of the oil pump  96  to the third mode CM 3  when the temperature of the motor  2  is within the third temperature range TR 3  higher than the second temperature range TR 2 . Therefore, when the temperature of the motor  2  becomes high, the operation mode of the oil pump  96  is switched to the operation mode in which the output of the oil pump  96  is large. As a result, when the temperature of the motor  2  becomes high, the flow rate of the oil O sent to the motor  2  can be suitably increased. Therefore, the motor  2  can be suitably cooled. In addition, since the output of the oil pump  96  can be reduced when the temperature of the motor  2  becomes low, the oil pump  96  can be driven with high energy efficiency. That is, the oil pump  96  can be controlled more efficiently. 
     Each temperature range in which each operation mode of the oil pump  96  described above is executed is determined based on, for example, a change in the temperature of the motor  2  caused by a change in the travel state of the vehicle equipped with the drive device  1 . The first temperature range TR 1  is determined based on, for example, a temperature range of the motor  2  when the vehicle travels on a flat land in an environment where the air temperature is ordinary temperatures or less. The second temperature range TR 2  is determined based on, for example, the temperature range of the motor  2  when the vehicle travels on an uphill in an environment where the air temperature is ordinary temperatures or less. The third temperature range TR 3  is determined based on, for example, the temperature range of the motor  2  when the vehicle travels on an uphill in an environment where the air temperature is higher than the ordinary temperatures. The ordinary temperatures is, for example, a temperature range of 5° C. or more and 35° C. or less defined in JIS Z 8703. 
     Thus, by determining the temperature range in which each operation mode is executed based on the temperature change of the motor  2  caused by the change in the travel state of the vehicle, the number of operation modes of the oil pump  96  can be easily reduced as compared with the case where the operation mode is provided for each predetermined temperature width, for example, every 10° C. Therefore, switching between the operation modes of the oil pump  96  is less likely to occur than a case where the operation mode is provided for each predetermined temperature width. As a result, the output of the oil pump  96  can be suppressed from changing frequently, and a load can be less likely to be applied to the oil pump  96 . Therefore, the oil pump  96  can be controlled more efficiently. 
     In the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is a temperature within a first intermediate temperature range TRa, the controller  70  sets the operation mode of the oil pump  96  to the first linear change mode LM 1 . The first intermediate temperature range TRa is a temperature range higher in temperature than the first temperature range TR 1  and lower in temperature than the second temperature range TR 2 . That is, the first intermediate temperature range TRa is a temperature range between the first temperature range TR 1  and the second temperature range TR 2 . The first intermediate temperature range TRa is narrower than the second temperature range TR 2 , for example. In the example of  FIG. 6 , the first intermediate temperature range TRa is a temperature range higher than 80° C. and lower than 100° C. 
     In the first linear change mode LM 1 , the controller  70  linearly changes, according to the temperature change of the motor  2 , the duty ratio of the pulse current supplied to the oil pump  96 . The duty ratio of the pulse current supplied to the oil pump  96  in the first linear change mode LM 1  linearly increases from the value DR 1  of the duty ratio in the first mode CM 1  to the value DR 2  of the duty ratio in the second mode CM 2  as the temperature of the motor  2  increases from the maximum temperature in the first temperature range TR 1  toward the minimum temperature in the second temperature range TR 2 . 
     Thus, in the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is higher than the first temperature range TR 1  and lower than the second temperature range TR 2 , the controller  70  linearly raises the output of the oil pump  96  as the temperature of the motor  2  obtained based on the temperature sensor  71  increases. Therefore, when the temperature of the motor  2  lies in between the first temperature range TR 1  and the second temperature range TR 2 , the flow rate of the oil O sent from the oil pump  96  to the motor  2  can be suitably controlled according to the temperature of the motor  2 . This allows the motor  2  to be cooled more suitably. Furthermore, the oil pump  96  can be driven with high energy efficiency. 
     Furthermore, by providing the first intermediate temperature range TRa, the first temperature range TR 1  and the second temperature range TR 2  are provided at an interval. Therefore, even if the temperature of the motor  2  slightly fluctuates, the operation mode of the oil pump  96  is less likely to be switched between the first mode CM 1  and the second mode CM 2 . This can suppress frequent switching between the first mode CM 1  and the second mode CM 2  in a short time, for example. Therefore, it is possible to further suppress a load from applying to the oil pump  96 , and to suppress the operation of the oil pump  96  from becoming unstable. 
     According to the present example embodiment, the difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  is 5° C. or more and 30° C. or less. Therefore, the first intermediate temperature range TRa can be set to a suitable range. Specifically, the first intermediate temperature range TRa can be suppressed from becoming too narrow. Therefore, even if the temperature of the motor  2  slightly fluctuates, the operation mode of the oil pump  96  can be less likely to be switched between the first mode CM 1  and the second mode CM 2 . Thus, it is possible to more suitably suppress a load from applying to the oil pump  96  and to further suppress the operation of the oil pump  96  from becoming unstable. In addition, the first intermediate temperature range TRa can be suppressed from becoming too wide. Therefore, when the temperature of the motor  2  changes to a certain extent, for example, it is possible to suppress the responsiveness from deteriorating when the operation mode of the oil pump  96  is switched between the first mode CM 1  and the second mode CM 2 . 
     The difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  is more preferably 10° C. or more and 20° C. or less. By setting the difference between the minimum temperature in the second temperature range TR 2  and the maximum temperature in the first temperature range TR 1  within such a numerical range, it is possible to more preferably suppress a load from applying to the oil pump  96  and to further suppress the operation of the oil pump  96  from becoming unstable. It is possible to further suppress a decrease in responsiveness when the operation mode of the oil pump  96  is switched between the first mode CM 1  and the second mode CM 2 . 
     In the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is a temperature within a second intermediate temperature range TRb, the controller  70  sets the operation mode of the oil pump  96  to the second linear change mode LM 2 . The second intermediate temperature range TRb is a temperature range higher in temperature than the second temperature range TR 2  and lower in temperature than the third temperature range TR 3 . That is, the second intermediate temperature range TRb is a temperature range between the second temperature range TR 2  and the third temperature range TR 3 . The second intermediate temperature range TRb is narrower than the second temperature range TR 2  and the first intermediate temperature range TRa, for example. In the example of  FIG. 6 , the second intermediate temperature range TRb is a temperature range higher than 130° C. and lower than 140° C. In the present example embodiment, the first temperature range TR 1 , the first intermediate temperature range TRa, the second temperature range TR 2 , the second intermediate temperature range TRb, and the third temperature range TR 3  are provided continuously in this order. 
     In the second linear change mode LM 2 , the controller  70  linearly changes, according to the temperature change of the motor  2 , the duty ratio of the pulse current supplied to the oil pump  96 . The duty ratio of the pulse current supplied to the oil pump  96  in the second linear change mode LM 2  linearly increases from the value DR 2  of the duty ratio in the second mode CM 2  to the value DR 3  of the duty ratio in the third mode CM 3  as the temperature of the motor  2  increases from the maximum temperature in the second temperature range TR 2  toward the minimum temperature in the third temperature range TR 3 . Thus, in the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is higher than the second temperature range TR 2  and lower than the third temperature range TR 3 , the controller  70  linearly raises the output of the oil pump  96  as the temperature of the motor  2  obtained based on the temperature sensor  71  increases. 
     Thus, in the present example embodiment, when the temperature of the motor  2  obtained based on the temperature sensor  71  is higher than the second temperature range TR 2  and lower than the third temperature range TR 3 , the controller  70  linearly raises the output of the oil pump  96  as the temperature of the motor  2  obtained based on the temperature sensor  71  increases. Therefore, when the temperature of the motor  2  lies in between the second temperature range TR 2  and the third temperature range TR 3 , the flow rate of the oil O sent from the oil pump  96  to the motor  2  can be suitably controlled according to the temperature of the motor  2 . This allows the motor  2  to be cooled more suitably. Furthermore, the oil pump  96  can be driven with high energy efficiency. 
     Furthermore, by providing the second intermediate temperature range TRb, the second temperature range TR 2  and the third temperature range TR 3  are provided at an interval. Therefore, even if the temperature of the motor  2  slightly fluctuates, the operation mode of the oil pump  96  is less likely to be switched between the second mode CM 2  and the third mode CM 3 . This can suppress frequent switching between the second mode CM 2  and the third mode CM 3  in a short time, for example. Therefore, it is possible to further suppress a load from applying to the oil pump  96 , and to suppress the operation of the oil pump  96  from becoming unstable. 
     According to the present example embodiment, the difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  is 5° C. or more and 30° C. or less. Therefore, the second intermediate temperature range TRb can be set to a suitable range. Specifically, the second intermediate temperature range TRb can be suppressed from becoming too narrow. Therefore, even if the temperature of the motor  2  slightly fluctuates, the operation mode of the oil pump  96  can be less likely to be switched between the second mode CM 2  and the third mode CM 3 . Thus, it is possible to more suitably suppress a load from applying to the oil pump  96  and to further suppress the operation of the oil pump  96  from becoming unstable. In addition, the second intermediate temperature range TRb can be suppressed from becoming too wide. Therefore, when the temperature of the motor  2  changes to a certain extent, for example, it is possible to suppress the responsiveness from deteriorating when the operation mode of the oil pump  96  is switched between the second mode CM 2  and the third mode CM 3 . 
     The difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  is more preferably 10° C. or more and 20° C. or less. By setting the difference between the minimum temperature in the third temperature range TR 3  and the maximum temperature in the second temperature range TR 2  within such a numerical range, it is possible to more preferably suppress a load from applying to the oil pump  96  and to further suppress the operation of the oil pump  96  from becoming unstable. It is possible to further suppress a decrease in responsiveness when the operation mode of the oil pump  96  is switched between the second mode CM 2  and the third mode CM 3 . 
     As shown in  FIG. 5 , in step S 4   b , the controller  70  determines whether or not the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than a predetermined first temperature T 1 . The first temperature T 1  is a temperature within the first temperature range TR 1 . The value of the first temperature T 1  is, for example, −20° C. or higher and −5° C. or lower. In the example of  FIG. 6 , the value of the first temperature T 1  is −5° C. 
     If determining in step S 4   b  that the temperature of the motor  2  is equal to or higher than the first temperature T 1 , the controller  70  repeats step S 4   a . On the other hand, if determining in step S 4   b  that the temperature of the motor  2  is lower than the first temperature T 1 , the controller  70  performs step S 4   c . In step S 4   c , the controller  70  limits the output of the motor  2 . That is, in the present example embodiment, the controller  70  limits the output of the motor  2  when the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than the predetermined first temperature T 1  in the first temperature range TR 1 . 
     In the present example embodiment, the output of the motor  2  limited based on the detection result of the temperature sensor  71  includes the torque of the motor  2  and the torque change rate of the motor  2 . By limiting the torque of the motor  2  and the torque change rate of the motor  2 , acceleration and a rapid rise of the acceleration of the vehicle are limited. In the present example embodiment, the limitation of the output of the motor  2  based on the detection result of the temperature sensor  71  is a limitation such that the seizure of the gears can be suppressed even if the oil O as lubricating oil is not supplied in meshing of the gears in the deceleration device  4  and the differential device  5 . 
     Here, when the temperature of the motor  2  is relatively low, the environment in which the vehicle travels is relatively low in temperature. Therefore, the oil O accommodated in the housing  6  is relatively low in temperature and the viscosity of the oil O becomes relatively high. When the viscosity of the oil O becomes too high, the oil O supplied to the transmission device  3  becomes less likely to form an oil film between gears meshing with each other. Since the oil O is less likely to be scooped by the ring gear  51 , the amount of the oil O itself supplied to the transmission device  3  becomes reduced. As a result, there has been a risk that the gears in the transmission device  3  are rubbed against each other to cause seizure. 
     In contrast, according to the present example embodiment, as described above, the controller  70  limits the output of the motor  2  based on the detection result of the temperature sensor  71 . Therefore, by limiting the output of the motor  2  when the environment in which the vehicle travels is relatively low in temperature, it becomes possible to reduce the load applied between the gears of the transmission device  3 . Thus, it is possible to suppress the occurrence of seizure by rubbing the gears in the transmission device  3 . Therefore, it is possible to suppress a failure from occurring in the drive device  1  under a relatively low temperature environment. 
     In the present example embodiment, the controller  70  limits the output of the motor  2  when the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than the predetermined first temperature T 1 . Therefore, it is possible to limit the output of the motor  2  under a relatively low temperature environment, and it is possible to suppress a failure from occurring in the drive device  1 . 
     According to the present example embodiment, the output of the motor  2  limited based on the detection result of the temperature sensor  71  includes the torque of the motor  2 . Therefore, it is possible to reduce a load applied between the gears of the transmission device  3 , and it is possible to suitably suppress the gears from rubbing each other and causing seizure. 
     According to the present example embodiment, the output of the motor  2  limited based on the detection result of the temperature sensor  71  includes the torque change rate of the motor  2 . This suppresses torque of the motor  2  from suddenly rising, and can suppress gears meshing with each other in the transmission device  3  from strongly colliding with each other. This can more suitably suppress the gears of the transmission device  3  from causing seizure. 
     In the present example embodiment, the output of the motor  2  limited based on the detection result of the temperature sensor  71  does not include the rotational speed of the motor  2 . Thus, in a relatively low temperature environment, the vehicle acceleration is limited while the vehicle speed is not. Thus, the vehicle speed can be gradually increased. Therefore, the vehicle can travel smoothly while suppressing a failure from occurring in the drive device  1 . 
     In the present example embodiment, the first temperature range TR 1  also includes a temperature lower than the first temperature T 1 . That is, in the present example embodiment, even if the temperature of the motor  2  becomes lower than the first temperature T 1 , the oil pump  96  continues to operate in the first mode CM 1 . As a result, the oil O continues to circulate in the drive device  1  by the oil pump  96  even under a relatively low temperature environment. Therefore, the oil O can be supplied to the transmission device  3  by the oil pump  96  even under a relatively low temperature environment. Therefore, it is possible to further suppress the occurrence of seizure by rubbing the gears in the transmission device  3 . Furthermore, as the oil O circulates in the drive device  1 , heat generated in the motor  2  or the like is applied to the oil O. Therefore, the temperature of the oil O can be suppressed from becoming too low, and the viscosity of the oil O can be suppressed from becoming too high. 
     As shown in  FIG. 5 , after limiting the output of the motor  2  in step S 4   c , the controller  70  performs step S 4   d . In step S 4   d , the controller  70  determines whether or not the temperature of the motor  2  obtained based on the temperature sensor  71  is equal to or higher than a second temperature T 2 . The second temperature T 2  is higher than the first temperature T 1 . The second temperature T 2  is a temperature within the first temperature range TR 1 . The value of the second temperature T 2  is, for example, −10° C. or higher and 5° C. or lower. In the example of  FIG. 6 , the value of the second temperature T 2  is 5° C. 
     If determining in step S 4   d  that the temperature of the motor  2  is lower than the second temperature T 2 , the controller  70  maintains the state in which the output of the motor  2  is limited. On the other hand, if determining in step S 4   d  that the temperature of the motor  2  is equal to or higher than the second temperature T 2 , the controller  70  performs step S 4   e . In step S 4   e , the controller  70  releases the limitation of the output of the motor  2 . That is, in the present example embodiment, after limiting the output of the motor  2 , when the temperature of the motor  2  obtained based on the temperature sensor  71  is equal to or higher than the second temperature T 2 , the controller  70  releases the limitation of the output of the motor  2 . 
     Here, when the temperature of the motor  2  becomes relatively high, the temperature of the entire drive device  1  also rises due to heat generation from the motor  2 . Therefore, the temperature of the oil O also rises, and the viscosity of the oil O becomes relatively low. Thus, it is possible to suitably provide an oil film between meshing gears in the transmission device  3 . Therefore, it is possible to suppress the gear from causing seizure even when the limitation of the output of the motor  2  is released. 
     The case where the temperature of the motor  2  becomes relatively high includes a case where the temperature of the environment in which the vehicle travels rises, and a case where the temperature of the motor  2  rises as the rotational speed of the motor  2  rises while the environment in which the vehicle travels remains relatively low. 
     After step S 4   e , the controller  70  returns the processing to step S 4   a . Thereafter, the controller  70  repeatedly executes steps S 4   a  to S 4   e  in step S 4  described above until the ignition switch IGS is turned off. In steps S 4   c , S 4   d , and S 4   e , the operation mode of the oil pump  96  is the first mode CM 1 . 
     As shown in  FIG. 3 , when the ignition switch IGS of the vehicle is turned off in step S 5 , the controller  70  performs step S 6 . In step S 6 , the controller  70  performs after-run control. As shown in  FIG. 7 , after-run control in step S 6  of the present example embodiment includes steps S 6   a  to S 6   f . In step S 6   a , the controller  70  stops drive of the motor  2 . 
     Next, in step S 6   b , the controller  70  drives the oil pump  96 , the refrigerant pump  120 , and the fan device  130 . That is, in the present example embodiment, the controller  70  drives the oil pump  96  after the ignition switch IGS of the vehicle is turned off. Therefore, the oil O is sent to the motor  2  by the oil pump  96 , thereby cooling the motor  2 . Therefore, the motor  2  can be cooled after the ignition switch IGS is turned off. 
     Here, in the vehicle equipped with the drive device  1 , after the ignition switch IGS is turned off, the ignition switch is sometimes turned on again at a relatively short interval. In this case, when the ignition switch is turned on again, the temperature of the motor  2  mounted on the drive device  1  sometimes remains relatively high. After the ignition switch IGS is turned on again, the output from the drive device  1  is not sometimes suitably obtained. Specifically, for example, the temperature of the motor  2  sometimes quickly becomes high, and the output of the motor  2  such as torque is sometimes limited. In this case, there is a case where the acceleration of the vehicle cannot be suitably obtained after the ignition switch IGS is turned on again. 
     On the other hand, according to the present example embodiment, as described above, the controller  70  can cool the motor  2  by driving the oil pump  96  after the ignition switch IGS of the vehicle is turned off. Therefore, the temperature of the motor  2  can be kept relatively low before the ignition switch is turned on again at a relatively short interval. Therefore, even when the ignition switch IGS is turned on at a relatively short interval after the ignition switch IGS is turned off, the output from the drive device  1  can be suitably obtained. 
     According to the present example embodiment, the controller  70  drives the oil pump  96 , the refrigerant pump  120 , and the fan device  130  after the ignition switch IGS of the vehicle is turned off. Thus, the refrigerant W in the radiator  110  is cooled by the fan device  130 , and the cooled refrigerant W is sent to the oil cooler  97  by the refrigerant pump  120 . The oil O cooled by the refrigerant W in the oil cooler  97  is sent to the motor  2  by the oil pump  96 , whereby the motor  2  is more suitably cooled. Therefore, the motor  2  can be more suitably cooled after the ignition switch IGS is turned off. Therefore, the temperature of the motor  2  can be kept more suitable low before the ignition switch is turned on again at a relatively short interval. Thus, even when the ignition switch IGS is turned on at a relatively short interval after the ignition switch IGS is turned off, the output from the drive device  1  can be obtained more suitably. 
     In step S 6   b , the controller  70  continues to drive the equipment being driven when the ignition switch IGS was turned off among the oil pump  96 , the refrigerant pump  120 , and the fan device  130 . On the other hand, in step S 6   b , the controller  70  starts driving, immediately after the ignition switch IGS is turned off, the equipment stopped when the ignition switch IGS was turned off among the oil pump  96 , the refrigerant pump  120 , and the fan device  130 . For example, in the state where the ignition switch IGS is turned on in the present example embodiment, the oil pump  96 , the refrigerant pump  120 , and the fan device  130  are in a driven state. Therefore, in step S 6   b , the controller  70  continues drive of the oil pump  96 , drive of the refrigerant pump  120 , and drive of the fan device  130 . 
     In step S 6   b  of the present example embodiment, the controller  70  transmits, to the vehicle control device  140 , a signal for the vehicle control device  140  to drive the refrigerant pump  120  and the fan device  130 . Thus, the vehicle control device  140  drives the refrigerant pump  120  and the fan device  130 . That is, in the present example embodiment, after the ignition switch IGS is turned off, the controller  70  drives the refrigerant pump  120  and the fan device  130  via the vehicle control device  140 . 
     Next, in step S 6   c , the controller  70  determines whether or not a second predetermined time has elapsed since the ignition switch IGS was turned off. The second predetermined time is, for example, 10 seconds or more and 40 seconds or less. The second predetermined time is such a time that the temperature change of the motor  2  does not occur when the motor  2  is cooled by driving the oil pump  96 , the refrigerant pump  120 , and the fan device  130  in a state where the drive of the motor  2  is stopped. The second predetermined time is, for example, a value obtained in advance by an experiment or the like. 
     If determining in step S 6   c  that the second predetermined time has elapsed, the controller  70  performs step S 6   d . In step S 6   d , the controller  70  stops the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . That is, if a predetermined time has elapsed after the ignition switch IGS is turned off, the controller  70  stops the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . In the present example embodiment, the controller  70  stops the drive of the refrigerant pump  120  and the drive of the fan device  130  via the vehicle control device  140  in the same manner as in the case of driving. 
     On the other hand, if determining in step S 6   c  that the second predetermined time has not elapsed, the controller  70  performs step S 6   e . In step S 6   e , the controller  70  determines whether or not the temperature of the motor  2  obtained based on the temperature sensor  71  is equal to or lower than a fourth temperature. The fourth temperature is a relatively high temperature. The value of the fourth temperature is, for example, the same as the value of the third temperature described above. The value of the fourth temperature may be different from the value of the third temperature. 
     If determining in step S 6   e  that the temperature of the motor  2  is higher than the fourth temperature, the controller  70  continues the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . Thus, the temperature of the motor  2  can be made equal to or lower than the fourth temperature. 
     On the other hand, if determining in step S 6   e  that the temperature of the motor  2  is equal to or lower than the fourth temperature, the controller  70  performs step S 6   f . In step S 6   f , the controller  70  determines whether or not the temperature change of the motor  2  per unit time is equal to or less than a predetermined threshold. The predetermined threshold is, for example, about several ° C. 
     The temperature change of the motor  2  per unit time can include a case in which the temperature of the motor  2  rises and a case in which the temperature of the motor  2  drops. For example, in a case where the ignition switch IGS is turned off immediately after the output of the motor  2  suddenly increases, the temperature of the motor  2  may rise with some lag after the drive of the motor  2  is stopped. 
     If determining in step S 6   f  that the temperature change of the motor  2  per unit time is greater than the predetermined threshold, the controller  70  continues the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . Thus, when the temperature change per unit time is relatively large, cooling of the motor  2  can be continued. 
     On the other hand, if determining in step S 6   f  that the temperature change of the motor  2  per unit time is equal to or less than the predetermined threshold, the controller  70  stops in step S 6   d  the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . Thus, the after-run control in step S 6  ends. 
     According to the present example embodiment, as in steps S 6   c , S 6   e , and S 6   f  described above, after the ignition switch IGS is turned off, the controller  70  stops the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130  based on the detection result of the temperature sensor  71 . Therefore, the oil pump  96 , the refrigerant pump  120 , and the fan device  130  are driven to suitably cool the motor  2  until the temperature of the motor  2  suitably drops. Thus, even when the ignition switch IGS is turned on at a relatively short interval after the ignition switch IGS is turned off, the output from the drive device  1  can be obtained more suitably. 
     According to the present example embodiment, as in step S 6   f  described above, when the temperature of the motor  2  obtained based on the temperature sensor  71  is a predetermined temperature, i.e., the fourth temperature or less, and the temperature change of the motor  2  per unit time is a predetermined threshold or less after the ignition switch IGS is turned off, the controller  70  stops the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . Therefore, even if the temperature of the motor  2  becomes relatively low, the cooling of the motor  2  can be ended when the temperature of the motor  2  comes to not change while the cooling of the motor  2  is continued while the temperature of the motor  2  fluctuates relatively largely. Thus, after the ignition switch IGS is turned off, the motor  2  is easily cooled to the maximum extent possible to be cooled by the oil pump  96  or the like, and it is possible to suppress the oil pump  96  or the like from being excessively continued to drive. Therefore, in the after-run control after the ignition switch IGS is turned off, the temperature of the motor  2  can be suitably lowered and the power consumption can be reduced. 
     For example, if a failure occurs in the temperature sensor  71 , even if the actual temperature of the motor  2  is sufficiently low, there is a possibility that the temperature of the motor  2  obtained based on the temperature sensor  71  is different from the actual temperature and does not satisfy the stop condition described above. In this case, the oil pump  96 , the refrigerant pump  120 , and the fan device  130  are driven more than necessary, and power consumption in the after-run control is likely to increase. 
     On the other hand, according to the present example embodiment, if the second predetermined time has elapsed after the ignition switch IGS is turned off, the controller  70  stops the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130 . Therefore, even when a failure occurs in the temperature sensor  71 , the drive of the oil pump  96 , the drive of the refrigerant pump  120 , and the drive of the fan device  130  can be stopped after the second predetermined time. Thus, the oil pump  96 , the refrigerant pump  120 , and the fan device  130  can be prevented from being driven more than necessary, and the power consumption in the after-run control can be prevented from increasing. 
     As shown in  FIG. 8 , the flow rate control of the oil pump  96  in step S 4  of the present example embodiment includes steps S 4 Aa to S 4 Ag. As shown in  FIG. 9 , in the present example embodiment, the operation mode of the oil pump  96  includes a first mode CM 1 , a second mode CM 2 , and a first linear change mode LM 1 . In the present example embodiment, the operation mode of the oil pump  96  does not include the third mode CM 3  and the second linear change mode LM 2  unlike the first example embodiment. As shown in  FIG. 8 , in step S 4 Aa, the controller  70  sets the operation mode of the oil pump  96  to the first mode CM 1 , and sets the oil O flow rate sent by the oil pump  96  to the first flow rate. 
     Next, in step S 4 Ab, the controller  70  determines whether or not the temperature of the motor  2  is equal to or lower than a third temperature T 3 . The third temperature T 3  is a relatively high temperature. The value of the third temperature T 3  is, for example, 80° C. or higher and 100° C. or lower. In the example of  FIG. 9 , the value of the third temperature T 3  is, for example, 80° C. 
     If determining in step S 4 Ab that the temperature of the motor  2  is higher than the third temperature T 3 , the controller  70  performs step S 4 Ac. In step S 4 Ac, the controller  70  increases the flow rate of the oil O sent by the oil pump  96  based on the temperature of the motor  2  and the temperature change of the motor  2 . Thus, when the temperature of the motor  2  is relatively high, it is possible to increase the flow rate of the oil O sent to the motor  2 , and it is possible to suitably cool the motor  2 . 
     Specifically, in step S 4 Ac, when the temperature change of the motor  2  per unit time is equal to or less than the predetermined value, the controller  70  sets the operation mode of the oil pump  96  to the first linear change mode LM 1 , and linearly changes the flow rate of the oil O sent by the oil pump  96  in accordance with the temperature of the motor  2  from the first flow rate to the second flow rate. This makes it possible to adjust an increase amount of the oil O sent to the motor  2  according to the temperature of the motor  2 . Therefore, the motor  2  can be suitably cooled with high energy efficiency. 
     On the other hand, in step S 4 Ac, if the temperature change of the motor  2  per unit time is greater than a predetermined value, the controller  70  shifts the operation mode of the oil pump  96  from the first mode CM 1  to the second mode CM 2  without passing through the first linear change mode LM 1 . Thus, the controller  70  sets the flow rate of the oil O sent by the oil pump  96  to the second flow rate greater than the first flow rate. Therefore, a sudden temperature rise of the motor  2  can be suppressed, and the motor  2  can be suitably cooled. 
     The graph shown in  FIG. 9  shows a case where the temperature change of the motor  2  per unit time is equal to or less than a predetermined value in step S 4 Ac. If the temperature change of the motor  2  per unit time is greater than a predetermined value in step S 4 Ac, the first linear change mode LM 1  is not provided, and the temperature range of the motor  2  in which the first mode CM 1  is executed and the temperature range of the motor in which the second mode CM 2  is executed are continuously provided with the third temperature T 3  as a boundary. 
     As shown in  FIG. 8 , if determining in step S 4 Ab that the temperature of the motor  2  is equal to or lower than the third temperature T 3 , the controller  70  performs step S 4 Ad. In step S 4 Ad, the controller  70  determines whether or not the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than a predetermined first temperature T 1 . The first temperature T 1  is a temperature lower than the third temperature T 3 . The value of the first temperature T 1  is, for example, −20° C. or higher and −5° C. or lower. 
     If determining in step S 4 Ad that the temperature of the motor  2  is equal to or higher than the first temperature T 1 , the controller  70  maintains, at the first flow rate, the flow rate of the oil O sent from the oil pump  96  to the motor  2  in step S 4 Aa, or returns it to the first flow rate, and then performs the step S 4 Ab again. 
     On the other hand, if determining in step S 4 Ad that the temperature of the motor  2  is lower than the first temperature T 1 , the controller  70  performs step S 4 Ae. In step S 4 Ae, the controller  70  stops drive of the oil pump  96  and limits the output of the motor  2 . That is, in the present example embodiment, the controller  70  stops the drive of the oil pump  96  when the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than the predetermined first temperature T 1 . Thus, in the present example embodiment, the first mode CM 1  is executed when the temperature of the motor  2  is within the temperature range equal to or higher than the first temperature T 1  and equal to or less than the third temperature T 3 . 
     According to the present example embodiment, the controller  70  stops drive of the oil pump  96  when the temperature of the motor  2  obtained based on the temperature sensor  71  is lower than the predetermined first temperature T 1 . If the viscosity of the oil O is relatively high in a relatively low temperature environment, it becomes difficult for the oil pump  96  to send the oil O to the motor  2 , and the load of the oil pump  96  increases. Therefore, by stopping the drive of the oil pump  96 , it is possible to suppress a large load from being applied to the oil pump  96 , and it is possible to reduce power consumption in the drive device  1 . On the other hand, since the temperature of the motor  2  is relatively low, even if the oil O is not sent by the oil pump  96 , the motor  2  is suppressed from causing a failure due to heat. Accordingly, by stopping the drive of the oil pump  96  when the temperature of the motor  2  is relatively low, it is possible to reduce the power consumption of the drive device  1  while suppressing a failure from occurring in the motor  2 . 
     As shown in  FIG. 8 , after limiting the output of the motor  2  in step S 4 Ae, the controller  70  performs step S 4 Af. In step S 4 Af, the controller  70  determines whether or not the temperature of the motor  2  obtained based on the temperature sensor  71  is equal to or higher than a second temperature T 2 . The second temperature T 2  is a temperature higher than the first temperature T 1  and lower than the third temperature T 3 . The value of the second temperature is, for example, −10° C. or higher and 5° C. or lower. 
     If determining in step S 4 Af that the temperature of the motor  2  is lower than the second temperature T 2 , the controller  70  stops drive of the oil pump  96  and maintains the state in which the output of the motor  2  is limited. On the other hand, if determining in step S 4 Af that the temperature of the motor  2  is equal to or higher than the second temperature T 2 , the controller  70  performs step S 4 Ag. In step S 4 Ag, the controller  70  resumes the drive of the oil pump  96  and releases the limitation of the output of the motor  2 . That is, in the present example embodiment, after limiting the output of the motor  2 , when the temperature of the motor  2  obtained based on the temperature sensor  71  is equal to or higher than the second temperature T 2 , the controller  70  resumes the drive of the oil pump  96  and releases the limitation of the output of the motor  2 . 
     Here, if the temperature of the motor  2  becomes relatively high, the viscosity of the oil O becomes relatively low, and hence the oil O can be easily sent by the oil pump  96 . Therefore, even if the drive of the oil pump  96  is resumed, the load applied to the oil pump  96  can be made relatively small. The motor  2  can be suitably cooled by the oil O sent from the oil pump  96 . 
     After step S 4 Ag, the controller  70  returns the processing to step S 4 Aa. That is, the flow rate of the oil O sent by the oil pump  96  when the drive is resumed in step S 4 Ag of the present example embodiment is set to the first flow rate. Thereafter, the controller  70  repeatedly executes steps S 4 Aa to S 4 Ag in step S 4 A described above until the ignition switch IGS is turned off. 
     The present disclosure is not limited to the example embodiment described above, but other configurations and methods can be employed. When the output of the motor is limited based on the detection result of the rotation sensor, the controller of the drive device may limit the output of the motor by any procedure and condition. For example, the controller may determine that the operation of the oil pump is abnormal and limit the output of the motor when the rotational speed of the pump unit obtained based on the rotation sensor fluctuates irregularly. The output of the motor limited based on the detection result of the rotation sensor is not particularly restricted and may include the torque change rate of the motor, may not include the rotational speed of the motor, and may not include the torque of the motor. The operation check of the oil pump by the controller may be performed other than immediately after the ignition switch of the vehicle is turned on. The operation check of the oil pump by the controller may be periodically performed from when the ignition switch of the vehicle is turned on to when the ignition switch is turned off. The controller may not limit the output of the motor based on the detection result of the rotation sensor. 
     When limiting the output of the motor based on the detection result of the temperature sensor, the controller of the drive device may limit the output of the motor by any procedure and condition. For example, the controller may limit the output of the motor when the temperature of the motor obtained based on the temperature sensor is relatively high. The output of the motor limited based on the detection result of the temperature sensor is not particularly restricted and may include the rotational speed of the motor, may not include the torque of the motor, and may not include the torque change rate of the motor. The controller may not stop the drive of the oil pump when limiting the output of the motor based on the detection result of the temperature sensor. When the temperature of the motor obtained based on the temperature sensor is equal to or higher than the first temperature and lower than the second temperature, the controller may stop the drive of the oil pump without limiting the output of the motor. In this case, the controller may resume the drive of the oil pump when the temperature of the motor becomes equal to or higher than the second temperature, and may limit the output of the motor when the temperature of the motor becomes lower than the first temperature. 
     The controller of the drive device may not limit the output of the motor based on the detection result of the temperature sensor. For example, the controller  70  of the first example embodiment described above may not limit the output of the motor  2  in step S 4 . In this case, step S 4  does not include steps S 4   b  to S 4   e , and includes only step S 4   a , for example. 
     The controller of the drive device may drive the oil pump under any procedure and condition when the oil pump, the refrigerant pump, and the fan device are driven after the ignition switch of the vehicle is turned off. For example, the controller may drive the oil pump, the refrigerant pump, and, the fan device after a certain period of time has elapsed after the ignition switch of the vehicle is turned off. The controller may not drive the refrigerant pump and the fan device after the ignition switch of the vehicle is turned off. The controller may stop the drive of the oil pump, the drive of the refrigerant pump, and the drive of the fan device under any condition after the ignition switch of the vehicle is turned off. The controller may stop the drive of the oil pump, the drive of the refrigerant pump, and the drive of the fan device regardless of the temperature of the motor after the ignition switch of the vehicle is turned off. The controller may not drive the oil pump after the ignition switch of the vehicle is turned off. 
     Each configuration and method described in this description can be combined as appropriate within a scope that does not give rise to mutual contraction. 
     Features of the above-described example embodiments and the modifications thereof may be combined appropriately as long as no conflict arises. 
     While example 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.