Motor device

Abstract

To cool a DCDC converter while minimizing the number of cooling pipes.SOLUTION: To provide a motor device that stores, in an identical case, a motor and a power control unit on which at least a DCDC converter is mounted, the case having a partition wall between the motor and the power control unit, the motor device including a cooling pipe which is arranged on the motor, through which a cooling medium circulates, and which has a first cooling hole for discharging the cooling medium to the motor and a second cooling hole for discharging the cooling medium to the partition wall. As a result, the DCDC converter can be cooled while limiting an increase in the number of cooling pipes.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a motor device. [Background technology]

[0002] Conventionally, as this type of motor device, one that has been proposed is equipped with a power control unit (PCU) having a drive circuit for driving the motor, and a cooling circuit that cools the power control unit with a cooling medium (cooling water) (see, for example, Patent Document 1). In this device, the cooling medium that cools the power control unit is circulated in a water jacket in the cylinder head of the engine. In this way, when there is a margin in the cooling performance of the cooling medium that cools the power control unit, the engine is cooled by the margin of cooling performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-25242 A Summary of the Invention [Problem to be solved by the invention]

[0004] In some motor devices that include a motor housed in a case, a cooling pipe through which a cooling medium flows is arranged above the motor, and the cooling medium is discharged from cooling holes formed in the cooling pipe to cool the motor. When a power control unit is housed in such a case, it is recognized that cooling the DC-DC converter in the power control unit is an important issue. One method for cooling the DC-DC converter is to add a new cooling pipe through which a cooling medium flows near the power control unit. However, this method increases the number of cooling pipes, making the entire device larger.

[0005] The motor device of the present disclosure has a primary object to cool the DC-DC converter while suppressing an increase in the number of cooling pipes. [Means for solving the problem]

[0006] The motor device of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The motor device of the present disclosure is A motor device in which a motor and a power control unit having at least a DC-DC converter are housed in the same case, the case having a partition between the motor and the power control unit, a cooling pipe disposed above the motor, through which a cooling medium flows, the cooling pipe having a first cooling hole for discharging the cooling medium to the motor and a second cooling hole for discharging the cooling medium to the partition wall; The gist of the project is to provide the following:

[0008] In the motor device disclosed herein, a cooling pipe is disposed above the motor. The cooling pipe includes a first cooling hole through which a cooling medium flows and for discharging the cooling medium to the motor, and a second cooling hole for discharging the cooling medium to the partition wall. This allows the power control unit and, in turn, the DCDC converter to be cooled via the partition wall by the cooling medium discharged from the second cooling hole to the partition wall using one cooling pipe. As a result, the DCDC converter can be cooled while suppressing an increase in the number of cooling pipes. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing an outline of the configuration of a motor device 20 according to the present embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing a cross-sectional configuration taken along line BB in FIG. [Diagram 3] FIG. 11 is an explanatory diagram for illustrating an outline of the configuration of a motor device 120 according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of the configuration of a motor device 20 of this embodiment. FIG. 1(a) is a diagram showing an outline of the configuration of a side of the motor device 20 with a portion cut away. FIG. 1(b) is a diagram showing an outline of the configuration of a cross section taken along line AA in FIG. 1(a). FIG. 2 is a diagram showing an outline of the configuration of a cross section taken along line BB in FIG. 1(b). In FIG. 2, the thick arrow indicates an example of the discharge direction of cooling oil.

[0011] 1 is a diagram showing an outline of the configuration of a motor device 20 of this embodiment. The motor device 20 is mounted on a hybrid vehicle that includes an engine, motors MG1 and MG2, a planetary gear whose carrier is connected to the crankshaft of the engine, a battery that exchanges power with the motors MG1 and MG2, and a power control unit (hereinafter referred to as "PCU") 30. The motor device 20 includes the motors MG1 and MG2, the PCU 30, and a cooling device 40.

[0012] The motors MG1 and MG2 are configured as, for example, synchronous generator motors. The motors MG1 and MG2 each include a rotor. The configuration of the rotor will be described in detail in another embodiment below. The rotor of the motor MG1 is connected to a sun gear of the planetary gear. The rotor of the motor MG2 is connected to a ring gear of the planetary gear.

[0013] The PCU 30 is disposed above the motors MG1 and MG2, and includes a drive circuit 32 and a DCDC converter 34. The drive circuit 32 is configured as a circuit for driving the motors MG1 and MG2, and includes two inverters for driving the motors MG1 and MG2, and a boost converter for boosting the voltage from the battery and supplying it to the inverter, although not shown. The drive circuit 32 is disposed above the DCDC converter 34. The DCDC converter 34 exchanges power between the drive circuit 32 and auxiliary devices or an auxiliary battery (not shown), with voltage conversion.

[0014] The motors MG1, MG2, and the PCU 30 are housed in the same case 22. The case 22 has a partition wall 22a between the motors MG1, MG2, and the PCU 30.

[0015] The cooling device 40 includes a strainer 42, axial cooling oil passages 44 and 46, and a cooling pipe 48. The strainer 42 is provided in an oil passage Pl for cooling oil as a cooling medium, and removes foreign matter contained in the cooling oil stored at the bottom of the case 22 and pumped up by an oil pump (not shown). The axial cooling oil passages 44 and 46 will be described in detail in another embodiment described later. The cooling pipe 48 is disposed above the motor MG2. The cooling pipe 48 extends in the axial direction of the motor MG2, with one end connected to the oil passage Pl and the other end reaching the vicinity of the DCDC converter 34. Cooling oil flows through the inside of the cooling pipe 48. The cooling pipe 48 includes a first cooling hole 48a and a second cooling hole 48b. The first cooling hole 48a is formed to face downward so that the cooling oil is discharged to the motor MG2. The second cooling hole 48b is formed to face diagonally downward so that the cooling oil is discharged to the partition wall 22a separating the DCDC converter 34 of the PCU 30 and the motor MG2. The cooling oil discharged from the first and second cooling holes 48a, 48b cools the motor MG2 and the DCDC converter 34, and falls to the bottom of the case 22. In this way, the motor MG2 is cooled by the cooling oil discharged from the first cooling hole 48a, and the DCDC converter 34 is cooled by the cooling oil discharged from the second cooling hole 48b. Therefore, the power control unit and the DCDC converter 34 can be cooled through the partition wall 22a by the cooling medium discharged from the second cooling hole 48b to the partition wall 22a using one cooling pipe 48. This allows the DCDC converter 34 to be cooled without adding a cooling pipe dedicated to cooling the DCDC converter 34, that is, while suppressing an increase in the number of cooling pipes. In the embodiment, the cooling oil is used as the cooling medium, but cooling water may be used instead of the cooling oil.

[0016] The motor device 20 of the present embodiment described above is provided with a cooling pipe 48 that is disposed above the motor MG2, through which cooling oil flows, and has a first cooling hole 48a for discharging the cooling oil to the motor MG2 and a second cooling hole 48b for discharging the cooling oil to the partition wall 22a. Therefore, the DC-DC converter 34 can be cooled while suppressing an increase in the number of cooling pipes.

[0017] In the above-described embodiment, the motor MG2 and the DCDC converter 34 are cooled by providing the first and second cooling holes 48a, 48b in the cooling pipe 48. However, the motor MG2 and the DCDC converter 34 may be cooled using the shaft cooling oil passage 46. FIG. 3 is an explanatory diagram for explaining an outline of the configuration of a motor device 120 of another embodiment. In the figure, the thick arrow indicates an example of the discharge direction of the cooling oil. The motor device 120 has the same configuration as the motor device 20, except that a part of the end plate Pe of the rotor R2 of the motor MG2 is bent. Therefore, detailed description of the same configuration as the motor device 20 is omitted.

[0018] Here, the rotor R2 and the shaft cooling oil passages 44, 46 of the motor MG2 will be described. The rotor R2 includes a rotor core Rcore having a plurality of laminated electromagnetic steel sheets in a hollow disk shape, end plates Pe arranged at both ends in the lamination direction of the electromagnetic steel sheets (axial direction of the motor MG2), and a rotor shaft Raxl penetrating the hollow of the rotor core Rcore. The shaft cooling oil passage 46 is formed so that one end is connected to the oil passage Pl, passes through the rotor shaft Raxl and the rotor core Rco of the rotor R2 of the motor MG2, and reaches the end plate Pe and opens at the other end. The rotor of the motor MG1 has the same configuration as the rotor R2 of the motor MG2 except for the different dimensions, so a detailed description will be omitted. The shaft cooling oil passages 44, 46 are supplied with cooling oil from the oil passage Pl. The cooling oil supplied to the shaft cooling oil passage 46 flows through the shaft cooling oil passage 46 and is discharged from the other end of the shaft cooling oil passage 46. The shaft core cooling oil passage 44 has the same configuration as the shaft core cooling oil passage 46 except that it is provided in the motor MG1, and therefore a detailed description thereof will be omitted.

[0019] In the motor device 120, a bent portion Pef that bends outward is formed around the opening of the shaft core cooling oil passage 46 of the end plate Pe. Such a bent portion Pef allows the cooling oil to be discharged from the opening of the shaft core cooling oil passage 46 in the direction toward the stator and the direction toward the partition wall 22a. This makes it possible to cool the DCDC converter 34 without adding a cooling pipe dedicated to cooling the DCDC converter 34, that is, while suppressing an increase in the number of cooling pipes.

[0020] In the above-described embodiment, the vehicle on which the motor device 20, 120 is mounted is in the form of a hybrid vehicle equipped with an engine, motors MG1, MG2, and planetary gears. However, the vehicle may be in the form of a hybrid vehicle in which the engine and motor MG2 are connected via a clutch without the motor MG1 or planetary gears, or in the form of an electric vehicle equipped with a motor MG2 without the engine, motor MG1, or planetary gears.

[0021] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be described. In the embodiment, the motor MG2 corresponds to the "motor", the PCU 30 corresponds to the "power control unit", the DCDC converter 34 corresponds to the "DCDC converter", the cooling pipe 48 corresponds to the "cooling pipe", the first cooling hole 48a corresponds to the "first cooling hole", and the second cooling hole 48b corresponds to the "second cooling hole".

[0022] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the Means for Solving the Problem column does not limit the elements of the invention described in the Means for Solving the Problem column, since the embodiment is an example for specifically explaining the form for implementing the invention described in the Means for Solving the Problem column. In other words, the interpretation of the invention described in the Means for Solving the Problem column should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the Means for Solving the Problem column.

[0023] The above describes embodiments for implementing the present disclosure, but the present disclosure is not limited to these embodiments, and it goes without saying that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure. [Industrial Applicability]

[0024] The present disclosure is applicable to the motor device manufacturing industry and the like. [Explanation of symbols]

[0025] 20, 120 motor device, 22a bulkhead, 30 power control unit (PCU), 32 drive circuit, 34 DCDC converter, 40 cooling device, 42 strainer, 44, 46 shaft core cooling oil passage, MG1, MG2 motor, Pe end plate, Pef bent portion, Pl oil passage, R2 rotor, Rcore rotor core, Raxl rotor shaft.

Claims

[Claim 1] A motor device in which a motor and a power control unit having at least a DC-DC converter are housed in a same case, the case having a partition between the motor and the power control unit, a cooling pipe disposed above the motor, through which a cooling medium flows, the cooling pipe having a first cooling hole for discharging the cooling medium to the motor and a second cooling hole in the partition wall for discharging the cooling medium A motor device comprising:

Images