Drive unit
By integrating the motor, reduction mechanism, and inverter with overlapping designs and optimized cooling air passages, the drive unit is miniaturized and efficiently cooled, addressing protrusion and air resistance issues.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- ASTEMO LTD
- Filing Date
- 2022-11-07
- Publication Date
- 2026-07-24
Smart Images
Figure 0007894795000001 
Figure 0007894795000002 
Figure 0007894795000003
Abstract
Description
Technical Field
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[0001] The present invention relates to a drive unit using a motor.
Background Art
[0002] Patent Document 1 discloses a saddle-riding type vehicle including a drive unit and a control unit (such as an inverter). This drive unit includes an electric motor and a reduction unit. The reduction unit is disposed on the left side of the electric motor. Further, the control unit is disposed on the right side of the electric motor.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0007] According to the present invention, the protrusion of the inverter from the motor and reduction mechanism can be suppressed, which can contribute to miniaturizing the drive unit. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 is a schematic diagram of a saddle-type vehicle. [Figure 2] Figure 2 is a perspective view of the drive unit. [Figure 3] Figure 3 is a plan view of the drive unit. [Figure 4] Figure 4 is a bottom view of the drive unit. [Figure 5] Figure 5 is a front view of the drive unit. [Figure 6] Figure 6 is a right side view of the drive unit. [Figure 7] Figure 7 is a cross-sectional view taken along line VII-VII in Figure 6. [Figure 8] Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 3. [Figure 9] Figure 9 is a cross-sectional view taken along the line IX-IX in Figure 3. [Figure 10] Figure 10 is a cross-sectional view taken along line XX in Figure 6. [Figure 11] Figure 11 is a plan view of the drive unit with the cover removed. [Figure 12] Figure 12 is a partial enlargement view of a partial passageway. [Modes for carrying out the invention]
[0009] [1 Saddle-type vehicle 10] Figure 1 is a schematic diagram of a saddle-type vehicle 10. The saddle-type vehicle 10 is an electric vehicle. For example, the saddle-type vehicle 10 is an electric two-wheeled vehicle. The saddle-type vehicle 10 is equipped with a drive unit 12. The power of the drive unit 12 is transmitted to the rear wheel 14 via drive system components (chain, belt, drive shaft, etc.) not shown. The saddle-type vehicle 10 moves forward as the rear wheel 14 is driven.
[0010] [2. Structure of drive unit 12] Figure 2 is a perspective view of the drive unit 12. Figure 3 is a top view of the drive unit 12. Figure 4 is a bottom view of the drive unit 12. Figure 5 is a front view of the drive unit 12. Figure 6 is a right side view of the drive unit 12. Figure 7 is a cross-sectional view taken along line VII-VII of Figure 6. Figure 8 is a cross-sectional view taken along line VIII-VIII of Figure 3. Figure 9 is a cross-sectional view taken along line IX-IX of Figure 3. Figure 10 is a cross-sectional view taken along line XX of Figure 6. Figure 11 is a top view of the drive unit 12 with the cover 62 removed. Note that "front-rear direction" as used in the following description corresponds to the "front-rear direction" of the saddle-type vehicle 10. Also, "up-down direction" as used in the following description corresponds to the "up-down direction" of the saddle-type vehicle 10. Also, "left-right direction" as used in the following description corresponds to the "left-right direction" of the saddle-type vehicle 10.
[0011] As shown in Figure 2, the drive unit 12 comprises a motor 16, a reduction mechanism 18, an inverter 20, and a fan 22 (Figure 7). The motor 16, reduction mechanism 18, inverter 20, and fan 22 are integrated. Furthermore, as shown in Figures 8 and 9, the drive unit 12 includes a cooling air passage 24 through which cooling air flows. Cooling air (outside air) introduced into the drive unit 12 by the fan 22 flows through the cooling air passage 24. The cooling air cools the motor 16 and the inverter 20.
[0012] The motor 16 is an alternating current motor. The motor 16 operates by being supplied with current from the inverter 20. As shown in FIGS. 7, 9, etc., the motor 16 includes a motor housing 26, a stator 28, a rotor 30, and a rotating shaft 32. The motor 16 shown in FIGS. 7, 9, etc. is an inner rotor type motor. The motor 16 is arranged such that the axis A of the motor 16 (the axis A of each of the stator 28, the rotor 30, and the rotating shaft 32) is orthogonal to the front-rear direction (the first direction) and the up-down direction. In other words, the motor 16 is arranged such that the axis A of the motor 16 extends in the left-right direction (the second direction).
[0013] In this specification, the portion of the motor 16 that is relatively located in the rear direction is referred to as the rear portion 34. Also, the portion of the motor 16 that is relatively located in the front direction is referred to as the front portion 36. The boundary between the rear portion 34 and the front portion 36 in the front-rear direction is a plane that includes the axis A of the motor 16 and extends in the up-down direction and the left-right direction. Further, in this specification, the portion of the outer wall surface of the motor housing 26 that surrounds the stator 28 around the axis is defined as the outer peripheral surface 38 of the motor 16.
[0014] As shown in FIG. 9, etc., in the rear portion 34, the outer peripheral surface 38 of the motor housing 26 includes an upper surface 40, a rear surface 42, and a lower surface 44. The upper surface 40 is directed upward. The rear surface 42 is directed rearward. The lower surface 44 is directed downward. On the other hand, in the front portion 36, the outer peripheral surface 38 of the motor 16 includes a curved surface 48. The curved surface 48 is located at a portion from the front end of the upper surface 40 to the front end of the lower surface 44. The curved surface 48 is an arc shape that protrudes forward along the outer periphery of the stator 28. Since the outer peripheral surface 38 of the front portion 36 is an arc shape, the air resistance generated in the drive unit 12 during traveling can be reduced. Also, as shown in FIG. 7, etc., the right surface 50 of the motor housing 26 is directed rightward. The left surface 52 of the motor housing 26 is directed leftward.
[0015] As shown in FIG. 9, FIG. 11, etc., a rear groove 54 is formed in the rear surface 42. Note that the inner surface of the rear groove 54 is included in the rear surface 42. The rear groove 54 extends in a direction (vertical direction) perpendicular to the rotation axis 32 along the rear surface 42. The rear groove 54 extends linearly from the lower end portion to the upper end portion of the rear surface 42. An upper groove 56 is formed in the upper surface 40. Note that the inner surface of the upper groove 56 is included in the upper surface 40. The upper groove 56 extends in a direction (front-rear direction) perpendicular to the rotation axis 32 along the upper surface 40. The upper groove 56 extends linearly from the rear end portion of the upper surface 40 to the boundary between the upper surface 40 and the curved surface 48. A curved groove 58 is formed in the curved surface 48. Note that the inner surface of the curved groove 58 is included in the curved surface 48. The curved groove 58 extends in a direction (circumferential direction of the stator 28) perpendicular to the rotation axis 32 along the curved surface 48. The curved groove 58 extends from the boundary between the upper surface 40 and the curved surface 48 to the boundary between the curved surface 48 and the lower surface 44.
[0016] As shown in FIG. 9, etc., the upper end portion of the rear groove 54 and the rear end portion of the upper groove 56 are connected to each other. Also, the front end portion of the upper groove 56 and the rear end portion of the curved groove 58 are connected to each other. Further, a plurality of heat radiation fins 60 are formed inside the upper groove 56 and inside the curved groove 58. The heat radiation fins 60 project from the bottom of the groove toward the outside of the groove. The heat radiation fins 60 extend along the longitudinal direction of the groove.
[0017] As shown in FIG. 3, FIG. 5, FIG. 9, etc., a resin cover 62 is attached to the upper surface 40 and the curved surface 48. The cover 62 covers all of the upper groove 56 and a part of the curved groove 58. As shown in FIG. 9, a part of the cooling air passage 24 is defined by the upper groove 56, the curved groove 58, and the cover 62. This part of the cooling air passage 24 is referred to as a partial passage 24c. The partial passage 24c extends along the upper surface 40 and the curved surface 48 on the radially outer side of the motor 16. That is, the partial passage 24c bends so as to project to the radially outer side of the motor 16 in a right side view.
[0018] As shown in Figure 9, etc., the cover 62 extends from a first end located at the rear end of the upper surface 40 to a second end located between the front and lower ends of the curved surface 48. The second end of the cover 62 is located at the discharge position P. An opening 64 of the cooling air passage 24 is formed at the discharge position P. The opening 64 is the outlet for the cooling air. The opening 64 discharges the cooling air that has flowed through the cooling air passage 24 (partial passage 24c). The opening 64 is formed to discharge the cooling air in a direction between downward and rearward.
[0019] As shown in Figure 3, etc., the reduction mechanism 18 is located to the left of the motor 16. The reduction mechanism 18 reduces the rotation of the motor 16 and transmits it to the rear wheel 14. As shown in Figures 7, 10, etc., the reduction mechanism 18 comprises a reduction gear case 66, a plurality of gears 68, and an output shaft 70. The reduction gear case 66 is attached to the motor housing 26. The reduction gear case 66 covers the plurality of gears 68. The left end of the rotating shaft 32 protrudes from the left side 52 of the motor housing 26.
[0020] As shown in Figures 7 and 10, in this embodiment, the multiple gears 68 include a first gear 68a, a second gear 68b, a third gear 68c, and a fourth gear 68d. The first gear 68a is mounted on the left end of the rotating shaft 32. The second gear 68b and the third gear 68c are mounted on the intermediate shaft 69. The fourth gear 68d is mounted on the output shaft 70. The rotating shaft 32, the intermediate shaft 69, and the output shaft 70 are parallel to each other. The first gear 68a and the second gear 68b mesh with each other. The third gear 68c and the fourth gear 68d mesh with each other. The output shaft 70 is connected to the rear wheel 14 via drive system components (chain, belt, drive shaft, etc.). With the above configuration, the power of the motor 16 is transmitted to the rear wheels 14 via the rotating shaft 32, the first gear 68a, the second gear 68b, the intermediate shaft 69, the third gear 68c, the fourth gear 68d, the output shaft 70, and the drive system components.
[0021] The more gears 68 and shaft members included in the reduction mechanism 18, the larger the reduction gear case 66 becomes. As shown in Figures 7 and 10, the reduction gear case 66 of this embodiment protrudes rearward compared to the stator 28. In this specification, the portion of the reduction mechanism 18 located behind the rear end 29 of the stator 28 is referred to as the protruding portion 72. The output shaft 70 is included in the protruding portion 72. The output shaft 70 is parallel to the rotation axis 32 of the motor 16. In the left-right direction, the right end of the output shaft 70 is located to the left of the left surface 52 of the motor housing 26.
[0022] As shown in Figure 3, the inverter 20 is located behind the motor 16. The inverter 20 converts the DC current supplied from the battery (not shown) into AC current and supplies it to the motor 16. As shown in Figure 7, the inverter 20 comprises an inverter case 74, an inverter board 76, and a heat sink 78. The inverter board 76 and the inverter case 74 are attached to the rear of the heat sink 78. The inverter case 74 covers the inverter board 76. The inverter board 76 is sealed by the inverter case 74 and the heat sink 78. The portion of the heat sink 78 facing forward is called the front surface 80. The heat sink 78 is attached to the rear surface 42 of the motor housing 26. As described above, the rear surface 42 includes the interior surface of the rear groove 54. In other words, a part of the cooling air passage 24 is defined by the front surface 80 (first wall surface) of the heat sink 78 and the rear surface 42 (second wall surface) of the motor housing 26. In other words, a portion of the cooling air passage 24 is defined by the front surface 80 (first wall surface) and the inner surface of the rear groove 54. This portion of the cooling air passage 24 is referred to as partial passage 24b. As shown in Figure 9, partial passage 24b is connected to partial passage 24a. Partial passage 24b is located upstream of partial passage 24a.
[0023] Figure 12 is a partially enlarged view of the partial passage 24b. Figure 12 is a cross-sectional view in a plane parallel to the front-rear and left-right directions. The heat sink 78 is provided with a plurality of heat dissipation fins 82 that protrude into the interior of the partial passage 24b. The heat dissipation fins 82 extend along the longitudinal direction (up-down direction) of the partial passage 24b. The wall surface of the rear surface 42 located at the bottom of the rear groove 54 is referred to as the bottom surface 42b. The distance D1 between a plurality of adjacent heat dissipation fins 82 is greater than the distance D2 between the tip 84 of the heat dissipation fin 82 and the bottom surface 42b of the rear surface 42. If the distance D2 is greater than the distance D1, the cooling air will flow more easily between the tip 84 of the heat dissipation fin 82 and the bottom surface 42b. On the other hand, the cooling air will not flow as easily between adjacent heat dissipation fins 82. As a result, the cooling effect of the heat sink 78 will be reduced. As in this embodiment, by making the distance D1 greater than the distance D2, the cooling air can more easily flow between adjacent heat dissipation fins 82. As a result, the cooling effect of the heat sink 78 is enhanced.
[0024] As shown in Figure 7, etc., the fan 22 is located to the right of the motor 16. The fan 22 is, for example, a sirocco fan. The fan 22 introduces outside air as cooling air into the drive unit 12. The right end of the rotating shaft 32 protrudes from the right side 50 of the motor housing 26. The fan 22 is attached to the right end of the rotating shaft 32. The outer circumference of the fan 22 is covered with a resin shroud 88. The shroud 88 is attached to the motor housing 26. The shroud 88 has an opening 90 and an inlet 92.
[0025] The opening 90 is an intake for cooling air. The opening 90 introduces outside air as cooling air into the cooling air passage 24 from the outside. The opening 90 is formed to introduce outside air from the right side. As shown in Figure 8, the introduction section 92 covers the outer circumference of the fan 22. Furthermore, as shown in Figures 4, 8, etc., the introduction section 92 covers a portion of the lower surface 44 of the motor housing 26. The introduction section 92 extends to the lower end of the rear groove 54 (partial passage 24b). As a result, as shown in Figure 8, a portion of the cooling air passage 24 is defined by the right surface 50 of the motor housing 26, the lower surface 44 of the motor housing 26, and the shroud 88. This portion of the cooling air passage 24 is referred to as the partial passage 24a. As shown in Figure 9, the partial passage 24a is connected to the partial passage 24b. The partial passage 24a is located upstream of the partial passage 24b.
[0026] [3 Positional relationship between motor 16, reduction mechanism 18, and inverter 20] As can be seen from Figures 3 and 5, in the front view, the inverter 20 is hidden behind the motor 16. In other words, in the first view, the inverter 20 is hidden behind the motor 16. That is, in the front view (first view), the motor 16 and the inverter 20 overlap. Also, as can be seen from Figures 3 and 6, in the right side view, the reduction mechanism 18 is hidden behind the inverter 20 and the motor 16. In other words, in the second view, the reduction mechanism 18 is hidden behind the inverter 20 and the motor 16. That is, in the right side view (second view), the reduction mechanism 18 and the inverter 20 overlap. Also, in the right side view, the reduction mechanism 18 and the motor 16 overlap. Furthermore, as can be seen from Figure 10, in the right side view, the output shaft 70 in the protruding portion 72 and the partial passage 24b overlap. Note that in the right side view, the output shaft 70 in the protruding portion 72 and the inverter 20 may overlap. Thus, in this embodiment, the inverter 20 is positioned in the space located behind the motor 16 and to the right of the reduction mechanism 18. This structure suppresses the protrusion of the inverter 20 from the motor 16 and the reduction mechanism 18. As a result, the drive unit 12 can be made smaller.
[0027] Furthermore, if at least a portion of the motor 16 and at least a portion of the inverter 20 overlap in a front view, it is possible to miniaturize the drive unit 12 to some extent. Also, if at least a portion of the reduction mechanism 18 and at least a portion of the inverter 20 overlap in a right side view, it is possible to miniaturize the drive unit 12 to some extent.
[0028] [4. Cooling airflow] In this embodiment, cooling air is introduced into the cooling air passage 24 by the rotation of the fan 22.
[0029] The fan 22 rotates in conjunction with the motor 16. For example, as shown in Figure 8, the fan 22 rotates clockwise in a right-side view. This introduces cooling air from the outside into the drive unit 12 through the opening 90. As indicated by arrow 94a in Figures 8 and 9, the cooling air introduced through the opening 90 flows through the partial passage 24a and reaches the lower end of the partial passage 24b.
[0030] As indicated by arrow 94b in Figure 9, the cooling air flows from the lower end of the partial passage 24b towards the upper end of the partial passage 24b and reaches the rear end of the partial passage 24c. That is, the cooling air flows upward through the partial passage 24b (in a direction intersecting the axial direction of the motor 16). The cooling air flowing through the partial passage 24b comes into contact with the heat dissipation fins 82 attached to the inverter case 74 and the bottom surface 42b of the rear groove 54 formed in the motor housing 26. As a result, the cooling air absorbs heat from the inverter 20 and the motor 16. Consequently, the inverter 20 and the motor 16 are cooled.
[0031] As indicated by arrow 94c in Figure 9, the cooling air flows along the partial passage 24c and reaches the opening 64. The cooling air flowing through the partial passage 24c comes into contact with the inner wall of the upper groove 56 and the heat dissipation fins 60 inside the upper groove 56. The cooling air flowing through the partial passage 24c also comes into contact with the inner wall of the curved groove 58 and the heat dissipation fins 60 inside the curved groove 58. As a result, the cooling air absorbs heat from the motor 16. The cooling air is discharged from the opening 64 in a direction between downward and backward.
[0032] The inverter 20 has lower heat resistance compared to the motor 16. To address this, in the cooling air passage 24, the section passage 24b for cooling the inverter 20 is positioned relatively upstream. Furthermore, in the cooling air passage 24, the section passage 24c for cooling the motor 16 is positioned relatively downstream. This structure allows for priority cooling of the inverter 20, thereby preventing failure of the inverter 20.
[0033] According to this embodiment, the cooling air that flows through the cooling air passage 24 is discharged from the opening 64 in a direction between downward and rearward. The cooling air discharged from the opening 64 is unlikely to hit the occupant of the saddle-type vehicle 10. Furthermore, the opening 64 discharges the cooling air in the opposite direction to the direction of travel of the saddle-type vehicle 10. Therefore, the running resistance caused by the cooling air can be reduced. In addition, since the opening 64 is not oriented forward, it is difficult for foreign objects to enter the opening 64 while the saddle-type vehicle 10 is in motion.
[0034] [5 Other Embodiments] The drive unit 12 does not necessarily have to include a fan 22. For example, a partial passage 24a may be formed in a cover member attached to the motor housing 26, or in the motor housing 26 itself. In this case, the intake port of the partial passage 24a is directed forward. As a result, outside air is introduced into the partial passage 24a from the intake port as the saddle-type vehicle 10 moves.
[0035] In the above embodiment, the partial passage 24c located at the front 36 has a shape that curves forward when viewed from the right side. Alternatively, the partial passage 24c located at the front 36 may have a shape in which multiple straight passages are connected and bent when viewed from the right side.
[0036] [6. Inventions obtained from the embodiments] The inventions that can be understood from the above embodiments are described below.
[0037] An aspect of the present invention is a drive unit (12) for driving a saddle-type vehicle (10), comprising a motor (16), a reduction mechanism (18) that reduces the rotation of the motor and transmits it to an output shaft (70), and an inverter (20) that controls the motor, wherein the motor, the reduction mechanism and the inverter are integrated, and the reduction mechanism has a protruding portion (72) that protrudes from the outer circumference of the stator (28) of the motor in a first direction intersecting the axial direction of the motor, wherein the motor and the inverter overlap in a first view along the first direction, and the protruding portion and the inverter overlap in a second view along the axial direction.
[0038] According to the above configuration, the protrusion of the inverter from the motor and reduction mechanism can be suppressed. As a result, the drive unit can be made smaller.
[0039] In an embodiment of the present invention, the axial direction of the motor corresponds to the left-right direction of the saddle-type vehicle, the front portion (36) of the motor is shaped in an arc in the second view, and the inverter may be located on the rear side of the motor.
[0040] According to the above configuration, the outer surface of the front part is arc-shaped, and the inverter is located behind the motor. This reduces the amount of protrusion of the inverter from the up-down and left-right directions of the motor. As a result, the air resistance generated in the drive unit when the vehicle is running can be reduced. In addition, according to the above configuration, since the inverter is located behind the motor, foreign objects such as stones are less likely to hit the inverter when the vehicle is running.
[0041] In an embodiment of the present invention, the drive unit may include a fan (22) that rotates in conjunction with the motor's rotating shaft (32) to supply cooling air, consisting of outside air, to at least one of the areas around the inverter and the motor.
[0042] According to the above configuration, the motor or inverter can be efficiently cooled by the cooling air introduced by the fan.
[0043] In an embodiment of the present invention, the drive unit includes a cooling air passage (24) through which cooling air introduced from outside the saddle-type vehicle flows, and a first partial passage (24b), which is part of the cooling air passage, may be located between the inverter and the motor.
[0044] With the above configuration, the motor and inverter can be cooled simultaneously. Furthermore, with the above configuration, since the cooling air passage is located between the motor and the inverter, in a first view along the first direction, the motor and the cooling air passage overlap, and in a second view along the axial direction, the protrusion and the cooling air passage overlap, thereby suppressing the protrusion of the cooling air passage from the motor and the reduction mechanism.
[0045] In an embodiment of the present invention, the first partial passage may be formed such that the direction of travel of the cooling air flowing inside the first partial passage intersects with the axial direction of the motor.
[0046] If the direction of travel of the cooling air flowing through the first section passage is aligned with the axial direction of the motor, the protrusion of the reduction mechanism will be positioned to obstruct the flow of the cooling air through the first section passage. As a result, the cooling air will not flow smoothly through the first section passage, and the cooling efficiency between the motor and the inverter will decrease. In contrast, in the above configuration, the direction of travel of the cooling air flowing through the first section passage intersects with the axial direction of the motor. In this case, there is nothing obstructing the direction of travel of the cooling air. As a result, the cooling air flows smoothly, and the cooling efficiency between the motor and the inverter is high.
[0047] In an embodiment of the present invention, the drive unit may include a fan that rotates in conjunction with the motor's rotating shaft to introduce the cooling air, which consists of outside air, into the cooling air passage.
[0048] According to the above configuration, the motor or inverter can be efficiently cooled by the cooling air introduced by the fan.
[0049] In an embodiment of the present invention, the inverter is provided with a heat sink (78) protruding into the first partial passage, and the heat sink may include a plurality of heat dissipation fins (82) extending along the longitudinal direction of the first partial passage.
[0050] With the above configuration, the inverter can be efficiently cooled by the heat dissipation fins.
[0051] In an embodiment of the present invention, the first partial passage is defined by a first wall surface (80) which is the wall surface of the inverter and a second wall surface (42, 42b) which is along the first wall surface and is the wall surface of the motor, and the heat sink is provided on the first wall surface, and the distance (D1) between a plurality of adjacent heat dissipation fins may be greater than the distance (D2) between the tip (84) of the heat dissipation fin and the second wall surface.
[0052] With the above configuration, cooling air flows more easily between adjacent heat sink fins than between the tip of a heat sink fin and the second wall. As a result, the cooling effect of the heat sink is enhanced.
[0053] In an embodiment of the present invention, the cooling air passage is formed to intersect the axial direction of the motor, and the cooling air passage includes a second partial passage (24c) extending along the radially outer outer surface (40, 48) of the motor, the second partial passage may be bent so as to protrude radially outward from the motor in the second view.
[0054] According to the above configuration, the contact area between the outer surface of the motor and the cooling air can be increased. Therefore, the temperature rise of the motor can be further suppressed, and the efficiency of the motor can be improved.
[0055] In an embodiment of the present invention, the first partial passage may be located upstream of the second partial passage.
[0056] With the above configuration, the inverter can be cooled preferentially over the motor, thereby improving the durability of the inverter.
[0057] In an embodiment of the present invention, the second partial passage includes an opening (64) for discharging the cooling air to the outside of the saddle-type vehicle, and the opening may be formed to discharge the cooling air in a direction between downward and rearward.
[0058] With the above configuration, the cooling air discharged from the opening is less likely to hit the occupant of the saddle-type vehicle. Furthermore, with the above configuration, the opening discharges the cooling air in the opposite direction to the direction of travel of the saddle-type vehicle. Therefore, the running resistance caused by the cooling air can be reduced. In addition, with the above configuration, since the opening is not oriented forward, foreign objects are less likely to enter the saddle-type vehicle through the opening while it is in motion.
[0059] In an embodiment of the present invention, the drive unit is provided with a resin shroud (88) around the fan, and a third partial passage (24a), which is part of the cooling air passage, is formed by the shroud, and the third partial passage may introduce outside air drawn in by the fan into the first partial passage.
[0060] The resin shroud is easy to mold. Therefore, with the above configuration, a portion of the cooling air passage can be easily formed.
[0061] In an embodiment of the present invention, the motor is provided with a resin cover (62) that covers the outer circumferential surface, and the second partial passage may be formed between the outer circumferential surface of the motor and the cover.
[0062] The resin cover is easy to mold. Therefore, with the above configuration, a portion of the cooling air passage can be easily formed.
[0063] In an embodiment of the present invention, the output shaft of the reduction mechanism is provided on the protruding portion, and the output shaft does not protrude from the protruding portion toward the inverter, and in the second view, the inverter or the first partial passage and the output shaft may overlap.
[0064] According to the above configuration, space can be secured for the inverter or the first partial passage to be positioned next to the protruding portion. According to the above configuration, the protrusion of the inverter or the first partial passage from the motor and reduction mechanism can be suppressed. As a result, the drive unit can be made smaller.
[0065] Furthermore, the present invention is not limited to the disclosure described above, and can take various configurations without departing from the spirit of the invention. [Explanation of symbols]
[0066] 10... Saddle-type vehicle 12... Drive unit 16…Motor 18…Reduction mechanism 20...Inverter 22...Fan 24…Cooling air passage 24a...Partial passage (3rd partial passage) 24b...Partial passage (first partial passage) 24c...Partial passage (second partial passage) 28...Stator 32...Rotation axis 36...Front 40…Top surface (outer surface) 42…Rear surface (second wall surface) 42b...Bottom surface (second wall surface) 48...Curved surface (outer surface) 62...Cover 64...Opening 70...Output shaft 72...Protruding part 78…Heat sink 80…Front (first wall) 82... Heat dissipation fins 84... Tip 88... Shroud
Claims
1. A drive unit for driving a saddle-type vehicle, Motor and, A reduction mechanism that reduces the rotation of the motor and transmits it to the output shaft, An inverter that controls the motor, A cooling air passage through which cooling air introduced from the outside of the aforementioned saddle-type vehicle flows, Equipped with, The motor, the reduction mechanism, and the inverter are integrated into one unit. The reduction mechanism includes a protruding portion that extends beyond the outer circumference of the stator of the motor in a first direction intersecting the axial direction of the motor, In a first view along the first direction, the motor and the inverter overlap, In a second view along the axial direction, the protruding portion and the inverter overlap. The first partial passage, which is part of the cooling air passage, is located between the inverter and the motor. The inverter is provided with a heat sink that protrudes into the first partial passage. The heat sink comprises a plurality of heat dissipation fins extending along the longitudinal direction of the first partial passage. Drive unit.
2. A drive unit for driving a saddle-type vehicle, Motor and, A reduction mechanism that reduces the rotation of the motor and transmits it to the output shaft, An inverter that controls the motor, A cooling air passage through which cooling air introduced from the outside of the aforementioned saddle-type vehicle flows, Equipped with, The motor, the reduction mechanism, and the inverter are integrated into one unit. The reduction mechanism includes a protruding portion that extends beyond the outer circumference of the stator of the motor in a first direction intersecting the axial direction of the motor, In a first view along the first direction, the motor and the inverter overlap, In a second view along the axial direction, the protruding portion and the inverter overlap. In the cooling air passage, a first partial passage for cooling the inverter is located relatively upstream, and a second partial passage for cooling the motor is located relatively downstream. Drive unit.
3. A drive unit according to claim 1 or 2, The axial direction of the motor corresponds to the left-right direction of the saddle-type vehicle. The front part of the motor is shaped in an arc in the second view, The inverter is located behind the motor, Drive unit.
4. A drive unit according to claim 1 or 2, The inverter is equipped with a fan that rotates in conjunction with the motor's rotating shaft to supply the cooling air, which consists of outside air, to at least one of the surroundings of the inverter and the motor. Drive unit.
5. The drive unit according to claim 2, The first partial passage is located between the inverter and the motor, Drive unit.
6. The drive unit according to claim 1, The first partial passage is formed such that the direction of travel of the cooling air flowing inside the first partial passage intersects with the axial direction of the motor. Drive unit.
7. The drive unit according to claim 2, The first partial passage is formed such that the direction of travel of the cooling air flowing inside the first partial passage intersects with the axial direction of the motor. Drive unit.
8. A drive unit according to claim 1 or 2, The system includes a fan that rotates in conjunction with the motor's rotating shaft to introduce the cooling air, which consists of outside air, into the cooling air passage. Drive unit.
9. The drive unit according to claim 1, The first partial passage is defined by a first wall surface which is the wall surface of the inverter and a second wall surface which is the wall surface of the motor and runs along the first wall surface. The heat sink is provided on the first wall surface, The distance between a plurality of adjacent heat dissipation fins is greater than the distance between the tip of the heat dissipation fin and the second wall surface. Drive unit.
10. The drive unit according to claim 6, The cooling air passage is formed to intersect with the axial direction of the motor, The cooling air passage includes a second partial passage extending along the radially outer outer surface of the motor. The second partial passage is bent so as to protrude radially outward from the motor in the second viewing direction. Drive unit.
11. The drive unit according to claim 2, The second partial passage is provided with an opening for discharging the cooling air to the outside of the saddle-type vehicle. The opening is formed to discharge the cooling air in a direction between downward and backward. Drive unit.
12. The drive unit according to claim 8, The aforementioned fan is surrounded by a resin shroud, The third partial passage, which is part of the cooling air passage, is formed by the shroud. The third partial passage introduces outside air drawn in by the fan into the first partial passage. Drive unit.
13. The drive unit according to claim 10, The motor is equipped with a resin cover that covers the outer surface of the motor, The second partial passage is formed between the outer surface of the motor and the cover. Drive unit.
14. A drive unit according to claim 1 or 5, The output shaft of the reduction mechanism is provided on the protruding portion, The output shaft does not protrude from the protruding portion toward the inverter side. In the second view, the inverter or the first partial passage and the output shaft overlap. Drive unit.