Electric pump with improved cooling efficiency and straddle-type electric vehicle with such a pump

Abstract

Electric pump (14), characterized in that it comprises: a first pump chamber (141) configured to pump a first coolant using a first rotatable body (1411); a second pump chamber (142) opposite to the first pump chamber (141) in an axial direction of a rotation axis of the first rotatable body (1411) and configured to pump a second coolant using a second rotatable body (1422) having a rotation axis coaxial with the aforementioned rotation axis; a drive chamber (143) disposed axially adjacent to the second pump chamber (142) and containing an electric motor (143M) capable of supplying drive power to both the first and second rotatable bodies (1411, 1422) using a common shaft (140); a heat exchanger (144) provided between the first and second pump chambers (141, 142) and configured to perform heat exchange between the first and second coolants; and a tube (1442) forming a flow path for one of the first and second coolants, wherein the heat exchanger (144) has a plurality of fins (1441) arranged in the axial direction, and the tube (1442) is provided to extend through the plurality of ribs (1441).

Description

[0001] The present invention mainly relates to an electric pump in a vehicle.

[0002] JP 2013-199844 A discloses a configuration of an in-vehicle electric pump with two types of pump chambers: a water pump chamber and an oil pump chamber. The water pump chamber is equipped with an impeller for pumping water. The oil pump chamber is provided with an inner rotor and an outer rotor for pumping oil. A motor chamber is provided between the water pump chamber and the oil pump chamber, in which an electric motor is arranged. The electric motor drives the impeller and the inner rotor with a common shaft. According to Patent Literature 1, an electric pump in which two types of pump chambers are combined is realized with a relatively compact configuration.

[0003] JP S 54-44 339 U discloses a pump having a first pump chamber and a second pump chamber, wherein the first coolant and the second coolant are pumped using a first and second rotatable body, respectively. The first and second pump chambers, as well as a drive chamber, are arranged axially relative to each other. A heat exchanger is provided between the first and second pump chambers, allowing heat exchange between the first and second coolants.

[0004] Incidentally, it is conceivable to implement water cooling and oil cooling using water or oil as the coolant, respectively. Therefore, the electric pump in Patent Literature 1 requires structural improvements, taking into account the heat exchange of the coolant, to improve cooling efficiency.

[0005] The present invention is to improve the cooling efficiency of an electric pump comprising two types of pump chambers with a relatively simple configuration.

[0006] According to one aspect of the present invention, the electric pump is characterized by a first pump chamber configured to pump a first coolant using a first rotatable body; a second pump chamber opposite to the first pump chamber in an axial direction of a rotation axis of the first rotatable body and configured to pump a second coolant using a second rotatable body having a rotation axis coaxial with the aforementioned rotation axis; a drive chamber disposed axially adjacent to the second pump chamber and containing an electric motor capable of supplying drive power to both the first and second rotatable bodies using a common shaft;a heat exchanger provided between the first and second pump chambers and configured to perform heat exchange between the first and second coolants; and a tube forming a flow path for one of the first and second coolants, the heat exchanger having a plurality of fins arranged in the axial direction, and the tube being provided to extend through the plurality of fins.

[0007] Further features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings. It should be noted that the same reference numerals refer to the same or similar components throughout the accompanying drawings.

[0008] According to the present invention, it is possible to improve the cooling efficiency in the electric pump described above.

[0009] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. Fig. 1 is a left side view illustrating an example of the configuration of a straddle type electric vehicle (electric two-wheeled vehicle). Fig. 2 is a block diagram illustrating an example of the configuration of a straddle-seat type electric vehicle. Fig. 3 is a sectional view showing an example of the internal structure of an electric pump (electric pump unit). Fig. 4 is a sectional view showing an example of the configuration of a heat exchanger. Fig. 5 is a block diagram illustrating another example of the configuration of a straddle-seat type electric vehicle. Fig. Figure 6 is a sectional view illustrating the internal structure of an electric pump.

[0010] Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that each drawing is a schematic representation of the structure or configuration of the embodiment, and the dimensions of individual elements shown in the drawings do not necessarily correspond to the actual dimensions. Furthermore, in each drawing, the same or similar components are designated by the same reference numerals, and the description of overlapping contents will be omitted below.

[0011] Fig. 1 is a left side view of a straddle-seat type electric vehicle (electric two-wheeled vehicle) 1 according to an embodiment. The straddle-seat type electric vehicle 1 is a type of vehicle in which a rider operates the vehicle while standing above a vehicle body 10. In the present embodiment, the straddle-seat type electric vehicle 1 is assumed to be a motorcycle having a seat SH for the rider to sit on, and a front wheel FW and a rear wheel RW.

[0012] The straddle seat type electric vehicle 1 further includes a head tube 191, a main frame 192, a down frame 193, a seat rail 194, a rotating frame 195, and a swing arm 196 in the vehicle body 10. Although not shown, because Fig. 1 is a right side view. In the present embodiment, the main frame 192, the down frame 193, the seat rail 194, the pivot frame 195, and the swing arm 196 are provided as a left and right pair, respectively. In another embodiment, the main frame 192, the down frame 193, and the seat rail 194 may be provided individually (they may not be a left and right pair). Note that the above-described frames 192 to 195 may be collectively represented as a body frame or the like.

[0013] The head pipe 191 is arranged in front of the vehicle body 10 so as to rotatably support a handlebar, and the rider can perform steering by rotating the handlebar to change the orientation of the front wheel FW via a front fork.

[0014] The pair of left and right main frames 192 are extended from the comfort frame 191 in the longitudinal direction of the vehicle body while being spaced apart from each other in the left-right direction. In the present embodiment, the main frame 192 includes an upper frame portion 1921 and a lower frame portion 1922. In this embodiment, to improve the strength of the main frame 192, a truss frame (a reinforcing member) is installed between the upper frame portion 1921 and the lower frame portion 1922.

[0015] In this embodiment, the down frame 193 extends downward and rearward from a front portion of the lower frame section 1922. In another embodiment, the down frame 193 may extend downward and rearward from the head tube 191. After extending downward and rearward, the down frame 193 may extend rearward (to a pivot frame 195, described below) to accommodate various vehicle components within the vehicle body 10. A seat rail 194 extends rearward from a rear portion of the main frame 192 and supports the load applied to the seat SH. In the present embodiment, the seat rail 194 includes an upper frame section 1941 and a lower frame section 1942.Although not shown here, a truss frame (reinforcing member) may be installed as the main frame 192 between the upper frame section 1941 and the lower frame section 1942 to increase the strength of the seat rail 194.

[0016] The pivot frame 195 extends downward from a rear portion of the main frame 192, and a swing arm 196 is supported by the pivot frame 195 while rotatably supporting the rear wheel RW.

[0017] The straddle-type electric vehicle 1 further includes a battery 11, an electric drive unit 12, a controller 13, an electric pump 14, and a heat exchanger 15. A rechargeable secondary battery is used for the battery 11, and examples include a lithium-ion battery and a nickel-hydrogen battery. The battery 11 is installed in the vehicle body 10 and, in this embodiment, is fixed to a predetermined portion of the vehicle body frame between the pair of left and right main frames 192. A charging port is provided on an exposed surface of the vehicle body 10, and the battery 11 can be charged by connecting a predetermined charging plug to this port.

[0018] The electric drive unit 12 generates the driving force (rotation) based on the electric energy of the battery 11. In the present embodiment, the electric drive unit 12 is fixed to a predetermined area of ​​the body frame in a space below the main frame 192, behind the down frame 193, and in front of the rotating frame 195. Thereby, the electric drive unit 12 is fixed to a position where the driving force can be appropriately transmitted to the rear wheel RW, and the driving force is transmitted to the rear wheel RW via, for example, a chain. An electric motor such as a three-phase asynchronous motor is used for the electric drive unit 12. The electric drive unit 111 may be represented as a motor unit or the like. Although details will be described later, the electric drive unit 12 is configured to be cooled by a predetermined cooling medium (for example,oil), and a storage portion 121 (e.g., oil pan) capable of storing the coolant is provided in a lower portion of the electric drive unit 12.

[0019] The control unit 13 has the function of converting a direct current into an alternating current and is also referred to as a PDU (Power Drive Unit) or the like, or further has the function of converting an alternating current into a direct current, a function of converting a voltage level, or the like and is also referred to as a PCU (Power Control Unit). For example, the control unit 13 converts the electric power of the battery 11 into a predetermined mode and supplies the electric power to the electric drive unit 12 to control the electric drive unit 12. In addition, the control unit 13 can also charge the battery 11 by using electric power generated by regenerative braking of the electric drive unit 12.In the present embodiment, the control unit 13 is arranged below and behind the battery 11 and is located next to the electric drive unit 12 in the vehicle width direction. With such an arrangement, it is possible to make a wiring (cable harness) required to supply the electrical energy of the battery 11 to the electric drive unit 12 relatively short.

[0020] Although details will be described later, the electric pump 14 circulates a coolant to cool the electric drive unit 12 and the control unit 13, respectively. For example, the electric pump 14 is arranged in front of the storage area 121 of the electric drive unit 12 and circulates a coolant (e.g., oil for cooling the electric drive unit 12) in the storage area 121. In the present embodiment, the electric pump 14 is integrally provided with a plurality of elements, which will be described below, and can be represented as an electric pump unit or the like.

[0021] The heat exchanger 15 is arranged in front of the vehicle body 10 so that it is struck by the airflow when the straddle-seat type electric vehicle 1 is traveling. Although details will be described later, the heat exchanger 15 utilizes this airflow to perform heat exchange with another coolant (e.g., water) pumped by the electric pump 14.

[0022] Fig. Figure 2 is a block diagram showing the configuration of the straddle-seat type 1 electric vehicle. The electric pump 14 includes two types of pump chambers 141 and 142, a drive chamber 143, and a heat exchanger 144. In the present embodiment, the pump chamber 141 is assumed to be a water pump chamber that pumps water as a coolant, and the pump chamber 142 is assumed to be an oil pump chamber that pumps oil as another coolant. The drive chamber 143, which will be described in detail later, drives the pump chambers 141 and 142 by using an electric motor to realize the above-described pumping of water and oil.

[0023] In the drawing, a flow path for water is shown by arrows with dashed lines, and the pipes P WA to P WC are shown as the pipes that form the flow path. Pipe P WA connects the water pump chamber 141 with the heat exchanger 15. The pipe P WBconnects the heat exchanger 15 with the control unit 13. The pipe P WC connects the control unit 13 to the water pump chamber 141.

[0024] Similarly, the flow path for oil is indicated by dashed line arrows, and the pipes P OA to P OC are shown as the pipes that form the flow path. Pipe P OA connects the heat exchanger 144 with the electrical unit 12. The line P OB connects the electric drive unit 12 with the oil pump chamber 142. The pipe P OC connects the oil pump chamber 142 with the heat exchanger 144.

[0025] The water pump chamber 141 pumps water via the pipe P WA to the heat exchanger 15. The water that has flowed through the heat exchanger 15 is cooled by heat exchange, then passes through the line P WB -Cooling (water cooling) control unit 13 and returns via line P WCto the water pump chamber 141. Note that a radiator is used as the heat exchanger 15, and the water flowing through the heat exchanger 15 is cooled by the wind generated when the straddle-seat type electric vehicle 1 travels as described above.

[0026] The water pump chamber 141 pumps water to the heat exchanger 15 and also pumps water to the heat exchanger 144. Although details will be described later, the water that has passed through the heat exchanger 144 is intended to be heated by heat exchange and then return to the water pump chamber 141.

[0027] The oil pump chamber 142 pumps oil via line P OC to the heat exchanger 144. The oil that has flowed through the heat exchanger 144 is cooled by heat exchange, then flows through the line P OAthe electric drive unit 12 to cool the electric drive unit 12 (oil cooling) and finally returns via the line P OB back into the oil pump chamber 142. Although omitted here, an oil filter for cleaning the oil may be provided further in the middle of the oil flow path.

[0028] Fig. Figure 3 is a schematic sectional view illustrating the internal structure of the electric pump 14. In this drawing, an X-axis, a Y-axis, and a Z-axis are shown intersecting each other to facilitate understanding of the structure (the same applies to the sectional views described later). The drawing shows a sectional view of the individual elements of the electric pump 14, while a water flow path is indicated by dashed arrows, and an oil flow path is indicated by dashed arrows.

[0029] The water pump chamber 141, the oil pump chamber 142, the drive chamber 143, and the above-described heat exchanger 144 are formed by dividing them by a casing 14H of the electric pump 14. The casing 14H may be formed by joining two or more parts by welding or fastening, or may be integrally cast. The water pump chamber 141 includes an impeller 1411 as a rotatable body for pumping water. The oil pump chamber 142 includes an inner rotor 1421 and an outer rotor 1422 as rotatable bodies for pumping oil. The drive chamber 143 includes an inner rotor 1431 provided with a magnet and an outer stator 1432 provided with a coil, and the inner rotor 1431 and the outer stator 1432 form an electric motor 143M.

[0030] The driving force (rotation) of the electric motor 143M is transmitted to the impeller 1411 in the water pump chamber 141 and the inner rotor 1421 in the oil pump chamber 142 via a common shaft 140. That is, the rotational axis of the impeller 1411 and the rotational axis of the inner rotor 1421 are supported on the same axis, and the impeller 1411 and the inner rotor 1421 are jointly driven by the electric motor 143M via the shaft 140. Here, it is assumed that the rotational axis of the impeller 1411 and the inner rotor 1421 is an axis AX1, and the axial direction corresponds to the X direction in the drawing.

[0031] As can be seen from the enlarged section (section through a YZ plane) of the water pump chamber 141 shown in the drawing, the shaft 140 is provided with a plurality of impellers 1411 around the shaft 140, and the plurality of impellers 1411 receive driving force from the electric motor 143M via the shaft 140 to be rotated. As a result, the water in the water pump chamber 141 is pumped as indicated by dashed arrows.

[0032] As can be seen from the enlarged sectional view (cross-section through a YZ plane) of the oil pump chamber 142 shown below in the drawing, the outer rotor 1422 is rotatably supported outside the inner rotor 1421 in accordance with the housing 14H. When the inner rotor 1421 rotates, receiving driving force from the electric motor 143M via the shaft 140, the outer rotor 1422 also rotates accordingly (the outer rotor 1422 rotates on a rotational axis different from the axis AX1). Meanwhile, the oil is to be sucked into a space between the inner rotor 1421 and the outer rotor 1422 through a suction port 1423 and then discharged from the space to a discharge port 1424. As a result, the oil in the oil pump chamber 142 is pumped, as indicated by the arrows of the dashed line.

[0033] In summary, a water pump chamber 141, which pumps water with the impeller 1411, and an oil pump chamber 142, which pumps oil with the inner rotor 1421 and the outer rotor 1422, are arranged adjacent to each other in the X direction. The impeller 1411 and the inner rotor 1421 are arranged so that their rotation axes are coaxial (on the axis AX1). Furthermore, the drive chamber 143 is arranged adjacent to the oil pump chamber 142 in the X direction, and the electric motor 143M of the drive chamber 143 supplies driving power to both the impeller 1411 and the inner rotor 1421 via the common shaft 140.

[0034] The heat exchanger 144 is provided between the water pump chamber 141 and the oil pump chamber 142. That is, in the present embodiment, the drive chamber 143, the oil pump chamber 142, the heat exchanger 144, and the water pump chamber 141 are arranged in this order in a +X direction. The heat exchanger 144 performs heat exchange between water and oil. This will be described below by focusing on the water w1 to w8 and oil o1 to o7, respectively, which form predetermined flow paths.

[0035] First, in the water pump chamber 141, the water that has flowed through the heat exchanger 15 and the control unit 13 is pumped through the pipe P WC (see w1) electric pump to the electric pump 14, and the water w1 that has returned to the water pump chamber 141 is pumped by the rotation of the pump impeller 1411 (see w2). Part of the pumped water w2 is discharged via the line P WA(see w3) is pumped to the heat exchanger 15, and another portion is pumped to the heat exchanger 144 (see w4). The water w4 pumped to the heat exchanger 144 flows into the heat exchanger 144 (see w5). The water w5 that has flowed into the heat exchanger 144 flows out of the heat exchanger 144 (see w6) after the heat exchange to be described later (see w6) and returns to the water pump chamber 141 (see w8) through a water path in the housing 14H (see w7). Subsequently, in the oil pump chamber 142, the oil that has passed through the electric drive unit 12 is pumped through the line P OB (see o1) to the electric pump 14 and returns to the oil pump chamber 142 through an oil path in the housing 14H (see o2). The oil o2 in the oil pump chamber 142 is pumped by the rotation of the inner rotor 1421 and the outer rotor 1422 (see o3). The pumped oil o3 is discharged through an oil path in the housing 14H (see o4) corresponding to the pipe P OC in Fig. 2, to the heat exchanger 144 (see o5). Note that the oil path to the heat exchanger 144 is annular in the circumferential direction of the shaft 140, and this oil o5 is also shown on the underside in the drawing. Although details will be described later, heat exchange takes place in the heat exchanger 144 between the oil o5 and the water w5 described above. After that, a portion of the oil 5 that has flowed through the heat exchanger 144 is supplied as lubricating oil to the bearings provided on the shaft 140 (see o6) and via line P OA (see o7) to the electric drive unit 12.

[0036] Fig. 4 is a schematic sectional view (a YZ plane sectional view) illustrating the internal structure of the heat exchanger 144. The heat exchanger 144 is formed by arranging a plurality of heat radiation fins 1441 within a heat exchange chamber 1440 formed by the casing 14H. In the present embodiment, the plurality of fins 1441 are arranged in the X direction, and each of the plurality of fins 1441 is a plate member (disk-shaped) having a disc shape. Note that a metal with a relatively high thermal conductivity, such as aluminum (Al) and iron (Fe), can be used for each fin 1441.

[0037] Below the heat exchange chamber 1440 there is an inlet connection 1443 through which the water w5 from Fig. 3, and above the heat exchange chamber 1440 a drain connection 1444 through which the water w6 from Fig. 3. This is intended to fill the heat exchange chamber 1440 with the water pumped from the water pump chamber 141. The heat exchange chamber 1440 will form part of the flow path for the water pumped from the water pump chamber 141.

[0038] In the heat exchange chamber 1440, a tube 1442 forming an oil flow path is provided so as to extend through a plurality of fins 1441. The tube 1442 includes a plurality of tubes 1442 provided so as to extend along the path between the tubes P OA and P OC in Fig. 3 and are arranged circumferentially around the shaft 140. As a result of oil flowing through the plurality of tubes 1442, the heat of the oil is transferred to the plurality of fins 1441, and heat exchange occurs between the oil and the water in the heat exchange chamber 1440, which accommodates both the plurality of tubes 1442 and the plurality of fins 1441. That is, the oil flowing through the tube 1442 is cooled by the water in the heat exchange chamber 1440.

[0039] Each of the plurality of fins 1441 can be arranged in an array parallel to a YZ plane. Furthermore, the inflow port 1443 and the outflow port 1444 can be arranged to face each other in the Z direction in the heat exchange chamber 1440. This allows the water in the heat exchange chamber 1440 to flow along the plurality of fins 1441 from the inflow port 1443 to the outflow port 1444, improving the heat exchange rate of the heat exchanger 144, i.e., cooling the oil accordingly.

[0040] In the present embodiment, since each of the plurality of fins 1441 has a disk shape, the heat exchange chamber 1440 accommodating them can be configured in a relatively simple manner, and the structure of the electric pump 14 can be made compact.

[0041] As described so far, according to the electric pump 14 of the present embodiment, the water pump chamber 141 and the oil pump chamber 142 are adjacent to each other in the X direction. The axis of the impeller 1411 of the water pump chamber 141 and the axis of the inner rotor 1421 of the oil pump chamber 142 are supported on the same axis (on the axis AX1). The impeller 1411 and the inner rotor 1421 receive the driving force from the electric motor 143M in the driving chamber 143 via the common shaft 140. In such a configuration, a heat exchanger 144 is provided between the water pump chamber 141 and the oil pump chamber 142 to perform heat exchange between water and oil. Thus, according to the present embodiment, it becomes possible to realize a structure configured by unifying the two types of pump chambers 141 and 142 and performing a heat exchange function therewith in a relatively compact manner.Therefore, according to the present embodiment, it is possible to improve the cooling efficiency in such an electric pump 14 with a relatively simple configuration.

[0042] The above-described configuration of the electric pump 14 is merely an example, and various changes may be made to the configuration of the electric pump 14 depending on the purpose or the like. For example, regarding the flow path for the coolant (water and oil in the embodiment), the order or path of the elements through which the coolant flows may be changed.

[0043] Fig. 5 is a block diagram as shown in Fig. 2, which shows the structure of an electric vehicle of straddle seat type 1 with an electric pump 14' instead of the electric pump 14 as another embodiment. While in the above-described electric pump 14 (see Fig. 2) the heat exchanger 144 and the heat exchanger 15 are arranged in parallel downstream of the water pump chamber 141, the heat exchanger 144 and the heat exchanger 15 are arranged in series corresponding to the electric pump 14' (see Fig. 5). Therefore, in the electric pump 14', all the water pumped from the water pump chamber 141 will flow through the heat exchanger 15 after passing through the heat exchanger 144. Fig. 6 shows how Fig. 3, a schematic sectional view illustrating the internal structure of the electric pump 14'. After the electric pump 14', all the water w2 pumped from the water pump chamber 141 is pumped to the heat exchanger 144 (see w4), ie the flow path for the water w3 from Fig. 3 is not provided. In addition, the water w7, which has flowed through the heat exchanger 144 in the electric pump 14', is then discharged via line P WApumped to the heat exchanger 15 (see w9), ie the flow path for the water w8 from Fig. 3 is not provided.

[0044] After the electric pump 14', all the water pumped from the water pump chamber 141 flows through the heat exchanger 144. This means that the flow path between the water pump chamber 141 and the heat exchanger 144 does not branch off. Therefore, all the water pumped from the water pump chamber 141 flows through the heat exchanger 144, allowing for effective heat exchange with the oil and cooling the oil accordingly. Therefore, a similar or better effect can be achieved with the electric pump 14' than with the electric pump 14'.

[0045] Note that in the examples of Fig. 5 and Fig.6 the above-described water (see w6, w7 and w9) which has received heat from the oil is pumped to the heat exchanger 15 to be cooled, and then flows through the control unit 13, thereby cooling the control unit 13, and then returns to the water pump chamber 141 (see w1).

[0046] As another example, the positions of the control unit 13 and the heat exchanger 15 in the water flow path may be reversed. This means that the water (see w6, w7, and w9) that absorbs heat from the oil is pumped to the control unit 13 to cool the control unit 13, then flows through the heat exchanger 15 for cooling, and can then return to the water pump chamber 141 (see w1).

[0047] Although some preferred modes have been exemplified above, the present invention is not limited to them, and some of them may be modified or combined within a range that does not deviate from the spirit of the present invention. Furthermore, it goes without saying that individual terms described in the present specification are used merely for the purpose of explaining the present invention, and the present invention is not limited to the strict meaning of the terms and may include their equivalents.

[0048] For example, the straddle type refers to a type in which a driver rides a vehicle straddling the vehicle body, and the concept of the "straddle type electric vehicle" described in the embodiment includes, in addition to two-wheeled vehicles (including scooter-type vehicles), three-wheeled vehicles (vehicles with one front wheel and two rear wheels or two front wheels and one rear wheel) and others. In addition, the electric pump 14 described in the embodiment can be used for various purposes and is not limited to application to the straddle type vehicle or the electric vehicle.

[0049] The features of the above-mentioned embodiments are summarized below: A first aspect relates to an electric pump (e.g., 14), and the electric pump comprises: a first pump chamber (e.g., 141) configured to pump a first coolant (e.g., water) using a first rotatable body (e.g., 1411); a second pump chamber (e.g., 142) opposite to the first pump chamber in an axial direction (e.g., X direction) of the rotation axis (e.g., AX1) of the first rotatable body and configured to pump a second coolant (e.g., oil) using a second rotatable body (e.g., 1422) having a rotation axis coaxial with the aforementioned rotation axis; a drive chamber (e.g. 143) arranged axially adjacent to the second pump chamber and containing an electric motor (e.g. 143M, 1431, 1432) capable of supplying drive power to both the first and second rotatable bodies using a common shaft (e.g. 140); and a heat exchanger (e.g.144) provided between the first and second pump chambers and configured to perform heat exchange between the first and second coolants.

[0050] According to the first aspect, it is possible to realize a compact structure that combines two types of pump chambers and further incorporates a heat exchange function by using them. This makes it possible to realize an electric pump capable of improving cooling performance with a relatively simple configuration. According to the invention, the electric pump further comprises a tube (e.g., 1442) forming a flow path for one of the first and second coolants, the heat exchanger comprising a plurality of fins (e.g., 1441) arranged in the axial direction, and the tube is provided so as to extend through the plurality of fins.

[0051] This makes it possible to carry out appropriate cooling (heat exchange with) one coolant (e.g. oil).

[0052] In a second aspect, each of the plurality of ribs is a plate member (e.g., 1441) having a disc shape.

[0053] According to the second aspect, it becomes possible to achieve a compact design of the electric pump described above.

[0054] In a third aspect, the tube comprises a plurality of tubes arranged so as to be circumferentially arranged around the shaft.

[0055] According to the third aspect, it becomes possible to carry out further suitable cooling (heat exchange with) the one coolant (e.g. oil).

[0056] In a fourth aspect, the heat exchanger comprises a heat exchange chamber (e.g., 1440) that receives a tube (e.g., 1442) that forms a flow path for one of the first and second coolants and operates as a flow path for another of the first and second coolants.

[0057] According to the fourth aspect, it becomes possible to carry out further suitable cooling (heat exchange with) the one coolant (e.g. oil).

[0058] In a fifth aspect, the heat exchanger comprises a plurality of fins (e.g., 1441) arranged in the axial direction; each of the plurality of fins is fixed at a position intersecting with the axial direction; an inflow port (e.g., 1443) of the other of the first and second coolants and an outflow port (e.g., 1444) of the other of the first and second coolants are provided in the heat exchange chamber; and the inflow port and the outflow port are opposed to each other in a direction (e.g., Z direction) intersecting the axial direction in the heat exchange chamber.

[0059] According to the fifth aspect, the other coolant (e.g. water) is more likely to flow along the fins, which can improve the efficiency of heat exchange between the two types of coolant.

[0060] In a sixth aspect, one of the first and second coolants is oil, and another of the first and second coolants is water.

[0061] According to the sixth aspect, it becomes possible to perform adequate cooling of (heat exchange with) oil, which is the only coolant.

[0062] A seventh aspect relates to a straddle type electric vehicle (e.g., 1), and the straddle type electric vehicle includes the above-described electric pump (e.g., 14) and the electric drive unit (e.g., 12) configured to drive a wheel (e.g., RW).

[0063] According to the seventh aspect, the electric pump described above can be appropriately applied to a typical / usual straddle type electric vehicle.

[0064] In an eighth aspect, the electric drive unit is configured to be cooled by one of the first and second coolants.

[0065] According to the eighth aspect, it is possible to perform adequate cooling (heat exchange with) the electric drive unit included in the straddle-seat type electric vehicle using one cooling medium (e.g., oil).

[0066] In a ninth aspect, the straddle-seat type electric vehicle further comprises: a second heat exchanger (e.g. 15) connected via a second conduit (e.g. P WA ) is connected to the electric pump and forms a flow path for another of the first and second cooling media; and a control device (e.g. 13) configured to control the electric drive unit based on the electrical energy of a battery (e.g. 11), wherein the control device is connected to the second heat exchanger and the electric pump via a third pipe (e.g. P WB or P WC) which forms a flow path for the other of the first and second coolants, so that the other of the first and second coolants which has passed through the second heat exchanger flows through the control unit and returns to the electric pump.

[0067] According to the ninth aspect, it becomes possible to carry out appropriate cooling of (heat exchange with) the other coolant (e.g. water), which is heated by heat exchange with the one coolant (e.g. oil) in the heat exchanger, in the second heat exchanger accordingly.

Claims

[1] Electric pump (14), characterized by that it includes: a first pump chamber (141) configured to pump a first coolant using a first rotatable body (1411); a second pump chamber (142) opposite to the first pump chamber (141) in an axial direction of a rotation axis of the first rotatable body (1411) and configured to pump a second coolant using a second rotatable body (1422) having a rotation axis coaxial with the aforementioned rotation axis; a drive chamber (143) disposed axially adjacent to the second pump chamber (142) and containing an electric motor (143M) capable of supplying drive power to both the first and second rotatable bodies (1411, 1422) using a common shaft (140); a heat exchanger (144) provided between the first and second pump chambers (141, 142) and configured to perform heat exchange between the first and second coolants; and a tube (1442) forming a flow path for one of the first and second coolants, wherein the heat exchanger (144) has a plurality of fins (1441) arranged in the axial direction, and the tube (1442) is provided to extend through the plurality of ribs (1441). [2] Electric pump (14) according to claim 1, characterized by that each of the plurality of ribs (1441) is a plate element having a disc shape. [3] Electric pump (14) according to claim 2, characterized by that the tube (1442) comprises a plurality of tubes (1442) which are provided so that they can be arranged circumferentially around the shaft (140). [4] Electric pump (14) according to one of claims 1 to 3, characterized by that the heat exchanger (144) includes a heat exchange chamber (1440) that receives a tube (1442) that forms a flow path for one of the first and second coolants and operates as a flow path for another of the first and second coolants. [5] Electric pump (14) according to claim 4, characterized by , that the heat exchanger (144) has a plurality of fins (1441) arranged in the axial direction; each of the plurality of ribs (1441) is fixed in a posture intersecting with the axial direction; an inlet port (1443) for the other of the first and second coolants and an outlet port (1444) for the other of the first and second coolants are provided in the heat exchange chamber (1440); and the inflow port (1443) and the outflow port (1444) face each other in a direction that intersects with the axial direction in the heat exchange chamber (1440). [6] Electric pump (14) according to claim 4 or 5, characterized by that one of the first and second coolants is oil, and the other of the first and second coolants is water. [7] Electric vehicle of straddle seat type (1), characterized by that it includes: an electric pump (14) according to one of claims 1 to 6; and an electric drive unit (12) configured to drive a wheel. [8] Electric vehicle of straddle type (1) according to claim 7 characterized by that the electric drive unit (12) is configured to be cooled by one of the first and second coolants. [9] Electric vehicle of straddle type (1) according to claim 8, characterized by that it further includes: a second heat exchanger (15) connected to the electric pump (14) via a second pipe forming a flow path for another of the first and second coolants; and a control unit (13) configured to control the electric drive unit (12) based on the electrical energy of a battery (11), wherein the control unit (13) is connected to the second heat exchanger (15) and the electric pump (14) via a third pipe which forms a flow path for the other of the first and second coolants, so that the other of the first and second coolants which has flowed through the second heat exchanger (15) passes through the control unit (13) and returns to the electric pump (14).

Images