Patent ID: 12212209

DETAILED DESCRIPTION

Hereinafter, an embodiment will be described with reference toFIGS.1to3. Note that, in this specification, components according to the embodiment and the description of the components will be described by a plurality of expressions. The components and the description thereof serve as an example, and are not limited by the expressions in this specification. The components can be identified by names different from those in this specification. In addition, the components can be described by expressions different from those in this specification.

FIG.1is a cross-sectional view schematically illustrating a hydraulic control device10according to an embodiment. The hydraulic control device10is an example of a motor unit, and can also be referred to as a pump unit. The hydraulic control device10is mounted on a vehicle1such as an automobile, for example. The hydraulic control device10adjusts pressure (hydraulic pressure) on a flow path of a brake device of the vehicle1. Note that the motor unit is not limited to the hydraulic control device10.

As illustrated in each drawing, in this specification, an X-axis, a Y-axis, and a Z-axis are defined for the sake of convenience. The X-axis, the Y-axis, and the Z-axis are orthogonal to each other. The X-axis is provided along the width of the hydraulic control device10. The Y-axis is provided along the length of the hydraulic control device10. The Z-axis is provided along the height of the hydraulic control device10.

Furthermore, in this specification, an X direction, a Y direction, and a Z direction are defined. The X direction is a direction extending along the X-axis, and includes a +X direction indicated by an arrow of the X-axis, and a −X direction being an opposite direction of the arrow of the X-axis. The Y direction is a direction extending along the Y-axis, and includes a +Y direction indicated by an arrow of the Y-axis, and a −Y direction being an opposite direction of the arrow of the Y-axis. The Z direction is a direction extending along the Z-axis, and includes a +Z direction (upper direction) indicated by an arrow of the Z-axis, and a −Z direction (lower direction) being an opposite direction of the arrow of the Z-axis.

The +Z direction is a vertical upper direction set in a case where the vehicle1is arranged on a horizontal ground surface, for example. The −Z direction is a vertical lower direction set in a case where the vehicle1is similarly arranged on a horizontal ground surface. Note that the hydraulic control device10may be arranged in such a manner that the Z direction is different from a vertical direction.

The hydraulic control device10includes a housing11, a motor12, a pump13, a coupling14, and an electronic control unit (ECU)15. The coupling14is an example of a joint. The hydraulic control device10further includes various components such as a solenoid valve, a pressure sensor, and a reservoir.

The housing11is a substantially rectangular parallelepiped block formed of metal or synthetic resin, for example. Note that the housing11is not limited to this example. The motor12, the pump13, and the ECU15are attached to the housing11. Other various components are also attached to the housing11.

The housing11includes a first mounting surface21and a second mounting surface22. The first mounting surface21and the second mounting surface22are outer surfaces of the housing11. The first mounting surface21is substantially flat, and faces the +Y direction. The second mounting surface22is opposite the first mounting surface21. The second mounting surface22is substantially flat, and faces the −Y direction.

The housing11is provided with a pump mounting hole25, a through-hole26, and a communication groove27. The pump mounting hole25is an example of a second chamber. The through-hole26is an example of a fifth chamber. The communication groove27is an example of a fourth chamber. In addition, the housing11may be provided with another hole and another groove. Furthermore, the housing11is provided with various flow paths.

The pump mounting hole25is a recess recessed from the first mounting surface21substantially in the −Y direction. The pump mounting hole25is open to an approximate center of the first mounting surface21. The pump mounting hole25is connected to a flow path of the brake device through a flow path provided in the housing11, for example.

The through-hole26penetrates through the housing11substantially in the Y direction. Thus, the through-hole26is open to the first mounting surface21and the second mounting surface22. The through-hole26is separated from the pump mounting hole25in the −Z direction. Thus, the through-hole26is located below the pump mounting hole25. Note that the through-hole26may be separated from the pump mounting hole25in another direction.

The communication groove27is open to the first mounting surface21, and extends between the pump mounting hole25and the through-hole26. Thus, the communication groove27is open to an inner surface25aof the pump mounting hole25and to an inner surface26aof the through-hole26. The inner surface25ais an inner surface of the housing11that forms, defines, or sections the pump mounting hole25. The inner surface26ais an inner surface of the housing11that forms the through-hole26. The pump mounting hole25and the through-hole26each communicate with the communication groove27. In addition, the through-hole26communicates with the pump mounting hole25through the communication groove27.

The motor12is a three-phase brushless motor, for example. Note that the motor12may be a motor of another type. The motor12includes a casing31, a motor shaft32, two bearings33, a rotor34, a stator35, an electrode36, and a slope member37. The motor shaft32is an example of a shaft. The slope member37is an example of a guide member. The slope member37in the present embodiment is included in the motor12. Nevertheless, the slope member37may be a component different from the motor12.

The casing31is attached to the first mounting surface21of the housing11. Thus, the first mounting surface21is oriented toward the motor12. The casing31covers the pump mounting hole25, the through-hole26, and the communication groove27.

The casing31has an internal space41. The internal space41is an example of a first chamber. A part of the motor shaft32, at least one of the bearings33, the rotor34, and the stator35are accommodated in the internal space41.

The motor shaft32is supported by the bearings33to be rotatable around an axis Ax. The axis Ax is an example of a rotation axis. The axis Ax is a center of the rotation of the motor shaft32.

The axis Ax is the axis of the motor shaft32, for example. Note that a center of the rotation of the motor shaft32may be different from the axis of the motor shaft32. In addition, the axis Ax includes not only an axis inside the motor shaft32, but also an extended line of the axis outside of the motor shaft32. The axis Ax extends substantially in the Y direction. A part of the motor shaft32protrudes from the internal space41in the −Y direction.

In the present embodiment, an axial direction, a radial direction, and a circumferential direction are defined for the sake of convenience. The axial direction is a direction extending along the axis Ax. In other words, the axial direction in the present embodiment is substantially equal to the Y direction. The radial direction is a direction orthogonal to the axis Ax. The circumferential direction is a direction around the axis Ax.

The pump mounting hole25of the housing11is located on the axis Ax. The through-hole26of the housing11is separated from the pump mounting hole25in the radial direction. In addition, the communication groove27of the housing11extends substantially in the radial direction, and allows the pump mounting hole25and the through-hole26to communicate with each other. Thus, the communication groove27is open to the inner surface25aof the pump mounting hole25substantially in the radial direction.

The rotor34is coupled to the motor shaft32. Thus, the rotor34is rotatable around the axis Ax together with the motor shaft32. The stator35surrounds the rotor34and is fixed to the casing31. By drive current flowing into the stator35, the rotor34and the motor shaft32integrally rotate around the axis Ax.

The casing31includes an outer frame45and an end frame46. The internal space41is a space surrounded by the outer frame45and the end frame46. In other words, the internal space41is defined by the outer frame45and the end frame46. Note that the internal space41is not limited to this example.

The outer frame45includes an outer wall51, an end wall52, and a mounting flange53. The outer wall51has a substantially cylindrical shape extending in the axial direction, and surrounds the axis Ax. The end wall52blocks an end portion in the +Y direction of the outer wall51. The end wall52supports one of the bearings33. The mounting flange53extends from an end portion in the −Y direction of the outer wall51toward the outside in the radial direction along the first mounting surface21.

The end frame46is attached to the outer frame45, and blocks the −Y directional end of the outer wall51. The end frame46includes an end wall55, an inner wall56, a bottom wall57, and a support wall58.

The end wall55has a substantially annular shape substantially orthogonal to the axis Ax and extending in the circumferential direction. The inner wall56has a substantially cylindrical shape extending in the +Y direction from the radially inside end of the end wall55, and surrounds the axis Ax.

The bottom wall57protrudes radially inward from the +Y direction end of the inner wall56. The bottom wall57has a substantially-annular shape, and surrounds the axis Ax. The support wall58has a substantially-cylindrical shape extending in the +Y direction from the radially inside end of the inner wall56, and surrounds the axis Ax. The support wall58supports the other one of the bearings33.

The end frame46includes an outer surface46aand a recessed surface46b. The outer surface46ais provided on the end wall55, and faces the outside of the motor12. The outer surface46ais oriented in the −Y direction, for example. The outer surface46aof the motor12and the first mounting surface21of the housing11face each other. The outer surface46ais separated from the first mounting surface21.

The recessed surface46bis provided on the inner wall56and the bottom wall57. The recessed surface46bis recessed from the outer surface46asubstantially in the +Y direction (axial direction). The recessed surface46bis located outside the internal space41. The space inside the recessed surface46bcommunicates with the internal space41through the space inside the support wall58. The bearing33supported by the support wall58separates the inside space of the recessed surface46band the internal space41.

The mounting flange53of the outer frame45is attached to the housing11using a screw, for example. For example, a seal material is provided between the mounting flange53and the first mounting surface21. The seal material seals a space between the casing31and the first mounting surface21in a liquid-tight manner.

The electrode36is a terminal for supplying drive current to the motor12, for example, and is electrically-connected to the stator35. Note that the electrode36may be a terminal electrically connected to a sensor provided in the motor12.

The electrode36protrudes substantially in the −Y direction from the outer surface46aof the end frame46. The electrode36penetrates through the through-hole26over the second mounting surface22. In other words, the electrode36is at least partially accommodated in the through-hole26.

The slope member37is formed of an insulator such as synthetic resin, for example. Note that the material of the slope member37is not limited to this example. The slope member37includes an outer wall61, a peripheral wall62, a flange63, and a cover64. The flange63can also be referred to as a rib. The outer wall61, the peripheral wall62, the flange63, and the cover64are integrated together.

The outer wall61has a substantially annular shape substantially orthogonal to the axis Ax and extending in the circumferential direction. The outer wall61is located between the first mounting surface21of the housing11and the end wall55of the end frame46. The outer wall61is attached to the end frame46, for example, and covers the outer surface46a. Note that the outer wall61may be attached to the housing11.

The outer wall61covers the communication groove27open to the first mounting surface21. With this configuration, the communication groove27can serve as a flow path connecting the pump mounting hole25and the through-hole26. In other words, a flow path (the communication groove27) connecting the pump mounting hole25and the through-hole26extends between the housing11and the motor12. Note that, in the above-described configuration, the flow path connecting the pump mounting hole25and the through-hole26is formed by providing a groove (the communication groove27) on the housing11side, but the flow path may be formed by providing a groove on the motor12side such as the outer wall61, for example, in place of this.

FIG.2is a cross-sectional view schematically illustrating a part of the hydraulic control device10according to the present embodiment. As illustrated inFIG.2, the peripheral wall62has a tubular shape surrounding the axis Ax. A −Y directional end62aof the peripheral wall62is connected to a radially inside end of the outer wall61.

The peripheral wall62is located inside the recessed surface46bof the end frame46. Thus, the peripheral wall62is located in a space inside the recessed surface46bbetween the internal space41and the pump mounting hole25of the housing11. Note that at least a part of the peripheral wall62may fall outside the inside space of the recessed surface46b.

A connected space65is formed inside the peripheral wall62. The connected space65is an example of a third chamber. The connected space65is a space surrounded by the peripheral wall62, and is formed by the peripheral wall62. The connected space65communicates with the pump mounting hole25of the housing11. In addition, the connected space65communicates with the internal space41through a space inside the support wall58.

The peripheral wall62includes an inner surface65aof the connected space65. The inner surface65aalso serves as an inner surface of the peripheral wall62having a tubular shape. In other words, the inner surface65aof the peripheral wall62forms the connected space65. In the present embodiment, the inner surface65ais a curved surface having a substantially circular cone shape (funnel shape), for example.

The inner surface65atapers in the +Y direction. In other words, the inner surface65atapers toward the internal space41. Thus, the diameter of the inner surface65alengthens as is closer to the pump mounting hole25. In other words, as is closer to the pump mounting hole25in the axial direction, the inner surface65aextends farther away from the axis Ax. The diameter of the inner surface65amay change uniformly or in a stepwise manner. Note that the inner surface65ais not limited to this example.

The inner surface65aincludes a lower portion71and an upper portion72. The lower portion71is an example of a guide. The lower portion71is a part (lower half) of the inner surface65abelow the axis Ax. Thus, in the radial direction the lower portion71is closer to the through-hole26and the communication groove27than the axis Ax. The upper portion72is a part (upper half) of the inner surface65aabove the axis Ax.

As described above, the diameter of the inner surface65alengthens as is closer to the pump mounting hole25. In addition, the communication groove27is open to the inner surface25aof the pump mounting hole25. Thus, in the axial direction the lower portion71of the inner surface65aextends farther away from the axis Ax as is closer to the communication groove27.

The lower portion71includes a first end71aand a second end71b. The first end71ais a −Y directional end of the lower portion71. In other words, the first end71ais a closer one of two axial ends of the lower portion71relative to the pump mounting hole25. The second end71bis the other of the axial ends of the lower portion71. In other words, the second end71bis a +Y directional end of the lower portion71.

For example, an angle between the axis Ax and the lower portion71is set larger than an allowable angle between the axis Ax and the horizontal direction at the time of manufacturing the vehicle1. In this case, even in a manufactured vehicle1with the axis Ax tilting with respect to the horizontal direction within the allowable angle range, a lowermost portion of the first end71ais located below a lowermost portion of the second end71b. In other words, the lower portion71extends while tilting obliquely downward from the second end71bto the first end71a.

In the present embodiment, the entire inner surface65ahas a substantially circular cone shape. Nevertheless, the upper portion72may have a substantially cylindrical shape extending in the axial direction, for example. In addition, the shape of a cross-section of the connected space65that is orthogonal to the axis Ax is not limited to a circular shape, and may be another shape such as a square.

A plurality of recesses73may be provided on the inner surface65a. For example, the recesses73are used for chucking in manufacturing. The plurality of recesses73is arranged at intervals in the circumferential direction. The plurality of recesses73is separated from a lowermost portion of the inner surface65a, at each position in the axial direction.

The flange63protrudes toward the axis Ax from an end62bof the peripheral wall62. The end62bis a closer one of two axial ends of the peripheral wall62relative to the internal space41. The flange63has a substantially annular shape, and surrounds the axis Ax. Thus, the flange63is provided with a hole75inside. The axis Ax extends through the hole75.

As illustrated inFIG.1, the cover64is located below the peripheral wall62, and protrudes substantially in the −Y direction from the outer wall61. The electrode36extends through the inside of the cover64. The cover64is accommodated in the through-hole26of the housing11together with the electrode36. In the through-hole26, the cover64covers the electrode36and protects the electrode36. In the vicinity of the second mounting surface22, a clearance gap between the inner surface26aof the through-hole26and the cover64is sealed in a liquid-tight manner.

The pump13is a gear pump, for example. Note that the pump13may be a pump of another type. At least a part of the pump13is accommodated in the pump mounting hole25. The pump13can feed operating oil to a flow path of the brake device.

The pump13includes a pump shaft81. The pump shaft81is an example of a rotary member. The pump shaft81is disposed substantially concentric with respect to the motor shaft32, and extends in the axial direction. Note that the axis of the pump shaft81and the axis Ax of the motor shaft32may deviate slightly from each other.

The pump shaft81is coupled to a rotator of the pump13, for example. The pump shaft81is rotatable around the axis Ax together with the rotator of the pump13. By the rotation of the pump shaft81and the rotator of the pump13around the axis Ax, the pump13feeds the operating oil.

A part of the pump shaft81and the rotator of the pump13are accommodated in the pump mounting hole25. The other part of the pump shaft81protrudes toward the outside of the pump mounting hole25, and is accommodated in the connected space65.

The motor shaft32and the pump shaft81are coupled to each other in the connected space65via the coupling14. In other words, the motor shaft32and the pump shaft81are coupled to each other inside the recessed surface46b, which is outside the internal space41. Note that the motor shaft32and the pump shaft81may be directly coupled to each other.

FIG.3is a perspective view illustrating the coupling14, the motor shaft32, and the pump shaft81according to the present embodiment in an exploded manner. As illustrated inFIG.3, the pump shaft81includes a base portion85and two clicks86.

The base portion85is a part of the pump shaft81at least partially accommodated in the connected space65. The base portion85has a substantially columnar shape extending in the axial direction. The two clicks86protrude substantially in the +Y direction from the base portion85. The two clicks86are arranged at a substantially-equal interval in the circumferential direction.

The motor shaft32includes a base portion91, two clicks92, and an intermediate portion93. As illustrated inFIG.2, the base portion91is a part of the motor shaft32that is outside of the internal space41. The base portion91has a substantially columnar shape extending in the axial direction. The base portion91extends through the hole75, and is surrounded by the flange63. A part of the base portion91is positioned in the connected space65.

The two clicks92protrude substantially in the −Y direction from the base portion91. The two clicks92are arranged at a substantially-equal interval in the circumferential direction. The clicks92are positioned between the base portion91and the base portion85of the pump shaft81. The clicks92are closer to the pump mounting hole25than the base portion91. The clicks92of the motor shaft32and the clicks86of the pump shaft81are alternately arranged in the circumferential direction.

The coupling14is interposed between the clicks92of the motor shaft32and the clicks86of the pump shaft81. Thus, the clicks92of the motor shaft32and the clicks86of the pump shaft81can convey force for rotation around the axis Ax to each other via the coupling14. In this manner, the coupling14couples the motor shaft32and the pump shaft81. Note that the motor shaft32and the pump shaft81may be coupled by another joint such as a universal joint.

As illustrated inFIG.3, the base portion91of the motor shaft32includes an outer circumferential surface91a. The outer circumferential surface91ais an example of a first outer circumferential surface. The outer circumferential surface91ais a curved surface having a cylindrical shape extending substantially in the axial direction, and is oriented outward in the radial direction. The outer circumferential surface91ais surrounded by the flange63.

The two clicks92each include an outer circumferential surface92a. The outer circumferential surface92ais an example of a second outer circumferential surface. The outer circumferential surface92ais a curved surface having a cylindrical shape extending substantially in the axial direction, and is oriented outward in the radial direction. The outer circumferential surface92ais closer to the pump mounting hole25than the outer circumferential surface91aof the base portion91. The outer circumferential surface92aof the click92is shorter in outer diameter than the outer circumferential surface91aof the base portion91.

The outer circumferential surface91aand the outer circumferential surface92amay not have a cylindrical shape. In this case, a portion of an end of the outer circumferential surface92ain the +Y direction that is farthest from the axis Ax is closer to the axis Ax than a portion of an end of the outer circumferential surface91ain the −Y direction that is farthest from the axis Ax.

The intermediate portion93is located between the base portion91and the clicks92. The intermediate portion93includes an outer circumferential surface93a. The outer circumferential surface93ais an example of a third outer circumferential surface. The outer circumferential surface93aconnects the outer circumferential surface91aof the base portion91and the outer circumferential surface92aof the click92. Since the outer circumferential surface92ais shorter in outer diameter than the outer circumferential surface91a, the outer circumferential surface93aintersects with the outer circumferential surface91aand the outer circumferential surface92a.

For example, the outer circumferential surface93aextends in a substantially circular cone shape between the outer circumferential surface91aof the base portion91and the outer circumferential surface92aof the click92. Note that the outer circumferential surface93amay be orthogonal to the outer circumferential surface91aand the outer circumferential surface92a.

The ECU15inFIG.1includes a substrate and various electric components mounted on the substrate, for example. Furthermore, the ECU15is electrically-connected to the motor12, for example, and controls the entire hydraulic control device10. For example, the electrode36of the motor12is electrically-connected to the ECU15by being connected to a connector mounted on the substrate. The ECU15supplies drive current to the motor12through the electrode36.

In the hydraulic control device10described above, operating oil sometimes leaks from the pump13. The operating oil moves downward by gravity. The communication groove27is open to the lower end of the pump mounting hole25in which the pump13is accommodated. Thus, the operating oil is discharged from the pump mounting hole25to the through-hole26through the communication groove27.

As described above, a space between the casing31and the first mounting surface21, and a clearance gap between the inner surface26aof the through-hole26and the cover64are sealed. Thus, the hydraulic control device10can reserve operating oil in the through-hole26and the communication groove27, and can prevent operating oil from flowing out to the outside of the hydraulic control device10.

On the other hand, if the ECU15drives the motor12, the motor shaft32, the coupling14, the pump shaft81, and the rotator of the pump13rotate around the axis Ax. The operating oil sometimes adheres to the motor shaft32, the coupling14, and the pump shaft81. Thus, the motor shaft32, the coupling14, and the pump shaft81that are rotating sometimes scatter operating oil substantially in the radial direction in the connected space65by centrifugal force.

The peripheral wall62surrounds the axis Ax. Thus, the peripheral wall62surrounds the motor shaft32extending in the axis Ax, the coupling14, and the pump shaft81. The inner surface65aof the peripheral wall62receives operating oil scattered substantially in the radial direction in the connected space65.

The lower portion71extends obliquely downward from the second end71btoward the first end71a. Thus, operating oil flows toward the first end71aalong the lower portion71. In other words, operating oil flows toward the communication groove27open to the inner surface25aof the pump mounting hole25.

Operating oil adhering to the upper portion72flows substantially in the circumferential direction along the upper portion72by gravity. The diameter of the upper portion72is longer as is closer to the pump mounting hole25. Thus, operating oil flowing along the upper portion72flows in such a manner as to get closer to the communication groove27in the axial direction.

As described above, operating oil received by the inner surface65aof the peripheral wall62(the connected space65) flows in such a manner as to get closer to the communication groove27. The communication groove27of the present embodiment communicates with the connected space65via the pump mounting hole25. Thus, operating oil flowing along the inner surface65ais discharged from the connected space65to the communication groove27.

The connected space65, the pump mounting hole25, the communication groove27, and the through-hole26are all located outside of the internal space41. Accordingly, by guiding the operating oil scattered in the connected space65to the communication groove27, the hydraulic control device10can prevent the operating oil from entering the internal space41.

For example, operating oil received by the upper portion72sometimes flows toward the internal space41along the upper portion72. In this case, the flange63receives the operating oil flowing along the upper portion72. The operating oil flows toward the lower portion71along the flange63having an annular shape, and is discharged to the communication groove27from the lower portion71.

In addition, for example, by braking of the vehicle1, the first end71aof the lower portion71is sometimes temporarily positioned superiorly to the second end71b. In this case, the operating oil sometimes flows toward the internal space41along the lower portion71. Nevertheless, the flange63receives the operating oil flowing along the lower portion71. If tilt caused by braking recovers, operating oil flows toward the communication groove27along the lower portion71.

As described above, the flange63receives operating oil flowing on the inner surface65atoward the internal space41. Accordingly, the hydraulic control device10can prevent operating oil from entering the internal space41.

The flange63is separated from the base portion91of the motor shaft32. A distance between the flange63and the base portion91is set to a length that can prevent a clearance gap between the flange63and the base portion91from holding operating oil.

In the motor shaft32, an outer diameter of the outer circumferential surface92aof the click92is shorter than an outer diameter of the outer circumferential surface91aof the base portion91. Thus, the outer circumferential surface93aof the intermediate portion93forms a stepwise portion between the outer circumferential surface91aand the outer circumferential surface92a.

Operating oil sometimes flows toward the internal space41along the outer circumferential surface92aof the click92. In this case, the stepwise portion of the outer circumferential surface93areceives the operating oil. The outer circumferential surface93arestricts operating oil from flowing toward the internal space41over the outer circumferential surface93a. The operating oil of which the movement is disturbed by the outer circumferential surface93ascatters toward the inner surface65aof the connected space65by centrifugal force. Accordingly, the hydraulic control device10can prevent operating oil adhering to the motor shaft32, from entering the internal space41over the hole75.

In the present embodiment, the peripheral wall62and the flange63are provided over the entire circumference around the axis Ax. Nevertheless, a hole, a cutout, or a slit may be provided on the peripheral wall62and the flange63.

In addition, in the present embodiment, the operating oil is discharged to the communication groove27open to the inner surface25aof the pump mounting hole25. Alternatively, the operating oil may be discharged in a direction intersecting with the axis Ax to a space (fourth chamber) open to the inner surface65aof the connected space65.

In addition, in the present embodiment, the coupling14, the motor shaft32, and the pump shaft81are positioned in the connected space65. Nevertheless, one or two of the coupling14, the motor shaft32, and the pump shaft81may be located outside of the connected space65.

In addition, in the present embodiment, the motor shaft32includes the outer circumferential surfaces91a,92a, and93a. Nevertheless, the coupling14or the pump shaft81may include a first outer surface surrounded by the flange63, a second outer surface being closer to the pump mounting hole25and having a short outer diameter, and a third outer surface connecting the first outer surface and the second outer surface, and intersecting with the first outer surface and the second outer surface.

In the hydraulic control device10according to the present embodiment described above, the slope member37includes the peripheral wall62. The peripheral wall62is located between the internal space41and the pump mounting hole25of the housing11. The peripheral wall62surrounds the axis Ax. The connected space65communicates with the pump mounting hole25inside the peripheral wall62. The communication groove27extends outside the internal space41and is open to at least one of the inner surface25aof the pump mounting hole25and the inner surface65aof the connected space65in a direction intersecting with the axis Ax. The inner surface65aof the connected space65includes the lower portion71being closer to the communication groove27than the axis Ax in the radial direction orthogonal to the axis Ax. The lower portion71extends farther away from the axis Ax as is closer to the communication groove27in the axial direction extending along the axis Ax. The motor shaft32and the pump shaft81may rotate while having the operating oil adhered thereto. In such a case, the operating oil scatters by centrifugal force. Since the peripheral wall62surrounds the axis Ax, such scattered operating oil can be received by the inner surface65aof the connected space65. By placing the hydraulic control device10with the communication groove27located below the axis Ax, the operating oil received by the inner surface65aof the connected space65flows by gravity toward the communication groove27along the lower portion71. As such, the hydraulic control device10can prevent the scattered operating oil from entering the internal space41and adhering to the rotor34and the stator35.

The inner surface65aof the connected space65extends farther away from the axis Ax as is closer to the communication groove27in the axial direction. In other words, not only the lower portion71but also substantially the entire inner surface65aof the connected space65extend farther away from the axis Ax as are closer to the communication groove27in the axial direction. With this configuration, the operating oil received by the inner surface65aof the connected space65above the axis Ax can flow toward the communication groove27while flowing downward by gravity. Thus, the hydraulic control device10can more efficiently prevent the scattered operating oil from entering the internal space41.

The motor12includes the outer surface46afacing the housing11, and the recessed surface46bbeing recessed from the outer surface46ain the axial direction and located outside the internal space41. The motor shaft32is coupled to the pump shaft81inside the recessed surface46b. The peripheral wall62is located inside the recessed surface46b. In other words, the peripheral wall62is located in a space inside the recessed surface46bin which the motor shaft32is coupled to the pump shaft81. This can avoid the hydraulic control device10from increasing in size in the axial direction as compared with the one including the peripheral wall62located outside of the recessed surface46b.

Between the two axial ends of the lower portion71, the lowermost portion of the first end71acloser to the pump mounting hole25is located below the lowermost portion of the second end71b. In other words, the lower portion71extends downward toward the pump mounting hole25. Thus, the operating oil can flow into the communication groove27along the lower portion71. In this manner, the hydraulic control device10can prevent the scattered operating oil from entering the internal space41.

The slope member37includes the flange63. The flange63surrounds the axis Ax and protrudes toward the axis Ax from the end62bof the peripheral wall62, the end62bbeing closer to the internal space41between the two axial ends. Thus, the flange63can receive the operating oil while flowing toward the internal space41along the inner surface65aof the connected space65. Accordingly, the hydraulic control device10can more surely prevent the scattered operating oil from entering the internal space41.

The motor shaft32, the pump shaft81, or the coupling14includes the outer circumferential surface91a, the outer circumferential surface92a, and the outer circumferential surface93a. The outer circumferential surface91ais surrounded by the flange63. The outer circumferential surface92ais closer to the pump mounting hole25than the outer circumferential surface91a, and shorter in outer diameter than the outer circumferential surface91a. The outer circumferential surface93aconnects the outer circumferential surface91aand the outer circumferential surface92a, and intersects with the outer circumferential surface91aand the outer circumferential surface92a. Thus, the operating oil is received by the outer circumferential surface93awhile flowing toward the outer circumferential surface91aalong the outer circumferential surface92a. The operating oil received by the outer circumferential surface93ascatters in the radial direction by centrifugal force. In other words, the outer circumferential surface93acan prevent the operating oil from flowing from the outer circumferential surface92ato the outer circumferential surface91a. In this manner, the hydraulic control device10can prevent the operating oil adhering to the outer circumferential surface92afrom entering the internal space41through the outer circumferential surface91a.

The motor shaft32includes the outer circumferential surface91a, the outer circumferential surface92a, and the outer circumferential surface93a. Among the motor shaft32, the pump shaft81, and the coupling14, the motor shaft32is closest to the internal space41. Most of the operating oil adhering to the pump shaft81and the coupling14scatters by centrifugal force in the pump shaft81and the coupling14in the radial direction. In other words, the pump shaft81and the coupling14can reduce the amount of the operating oil flowing toward the motor shaft32along the pump shaft81and the coupling14. The operating oil, when flowing to the motor shaft32from the pump shaft81and the coupling14, is received by the outer circumferential surface93a, and scatters in the radial direction by centrifugal force. As such, the hydraulic control device10can reduce the amount of the operating oil flowing toward the outer circumferential surface93aby the pump shaft81and the coupling14, and more surely prevent the operating oil from entering the internal space41through the outer circumferential surface91a.

The housing11is provided with the through-hole26communicating with the communication groove27. The motor12includes the electrode36accommodated in the through-hole26. The slope member37includes the cover64being integrated with the peripheral wall62to cover the electrode36in the through-hole26. Thus, the operating oil, when received by the inner surface65aof the connected space65, flows into the through-hole26through the communication groove27. The integration of the peripheral wall62forming the connected space65and the cover64covering the electrode36makes it possible to prevent the operating oil from adhering to the electrode36. Furthermore, as compared with the one including the peripheral wall62and the cover64separated, the hydraulic control device10can prevent the operating oil from entering the clearance gap between the slope member37and another component, and allows the operating oil to smoothly flow from the connected space65to the through-hole26. In addition, the hydraulic control device10can reserve the operating oil in a wider space by allowing the operating oil to flow into the through-hole26.

In the embodiment, the pump shaft81of the pump13is an example of a rotary member. Nevertheless, the rotary member is not limited to this example, and may be a gear, an arm, or another rotary member. The motor shaft32may be coupled to a rotary member different from the pump13. In such a case, the slope member37can prevent the lubricating oil on the rotary member from entering the internal space41, for example.

A motor unit according to at least one embodiment described above includes, as an example: a motor provided with a first chamber and including a shaft rotatable around a rotation axis, a rotor rotatable around the rotation axis together with the shaft, and a stator surrounding the rotor, the rotor and the stator being accommodated in the first chamber; a rotary member coupled to the shaft outside the first chamber, and rotatable around the rotation axis; a housing to which the motor is attached, and being provided with a second chamber accommodating at least a part of the rotary member; and a guide member including a peripheral wall located between the first chamber and the second chamber and surrounding the rotation axis, the guide member being provided with a third chamber communicating with the second chamber inside the peripheral wall, wherein the motor unit is provided with a fourth chamber which is outside the first chamber and is open to at least one of an inner surface of the second chamber and an inner surface of the third chamber in a direction intersecting with the rotation axis, the inner surface of the third chamber includes a guide being closer to the fourth chamber than the rotation axis in a radial direction orthogonal to the rotation axis, and the guide extends farther away from the rotation axis as is closer to the fourth chamber in an axial direction extending along the rotation axis. As an example, when the shaft and the rotary member rotate while having liquid adhered thereto, the liquid scatters by centrifugal force. Because of the peripheral wall surrounding the rotation axis, the scattering liquid can be received by the inner surface of the third chamber. By placing the motor unit with the fourth chamber located below the rotation axis, the liquid, when received by the inner surface of the third chamber, flows into the fourth chamber along the guide by gravity. In this manner, the motor unit can prevent the scattered liquid from entering the first chamber and adhering to the rotor and the stator.

In the motor unit, as an example, the inner surface of the third chamber extends farther away from the rotation axis as is closer to the fourth chamber in the axial direction. As an example, the liquid received by the inner surface of the third chamber above the rotation axis can flow toward the fourth chamber while flowing downward by gravity. As such, the motor unit can more efficiently prevent the scattered liquid from entering the first chamber.

In the motor unit, as an example, the motor includes an outer surface facing the housing, and a recessed surface recessed from the outer surface in the axial direction and located outside the first chamber, the shaft is coupled to the rotary member inside the recessed surface, and the peripheral wall is located inside the recessed surface. As an example, the peripheral wall is placed in the space inside the recessed surface in which the shaft is coupled to the rotary member. As such, the motor unit can be prevented from increasing in size in the axial direction as compared with the one including the peripheral wall located outside the recessed surface.

In the motor unit, as an example, between two axial ends of the guide, a lowermost portion of one axial end closer to the second chamber is located below a lowermost portion of the other axial end. As an example, the guide extends downward toward the second chamber. Thus, the liquid flows into the fourth chamber along the guide. In this manner, the motor unit can prevent the scattered liquid from entering the first chamber.

In the motor unit, as an example, the guide member includes a flange that surrounds the rotation axis and protrudes toward the rotation axis from one of two axial ends of the peripheral wall, the one being closer to the first chamber. As an example, the flange can receive the liquid while flowing toward the first chamber along the inner surface of the third chamber. In this manner, the motor unit can more surely prevent the scattered liquid from entering the first chamber.

In the motor unit, as an example, the shaft, the rotary member, or a joint that couples the shaft and the rotary member includes a first outer circumferential surface surrounded by the flange, a second outer circumferential surface closer to the second chamber than the first outer circumferential surface, and a third outer circumferential surface connecting the first outer circumferential surface and the second outer circumferential surface and intersecting with the first outer circumferential surface and the second outer circumferential surface, and the second outer circumferential surface is shorter in outer diameter than the first outer circumferential surface. As an example, the liquid can be received by the third outer circumferential surface while flowing toward the first outer circumferential surface along the second outer circumferential surface. The liquid, when received by the third outer circumferential surface, scatters in the radial direction by centrifugal force. In other words, the third outer circumferential surface can prevent the liquid from flowing from the second outer circumferential surface to the first outer circumferential surface. As such, the motor unit can prevent the liquid adhering to the second outer circumferential surface from entering the first chamber through the first outer circumferential surface.

In the motor unit, as an example, the shaft includes the first outer circumferential surface, the second outer circumferential surface, and the third outer circumferential surface. As an example, since the shaft is closest to the first chamber among the shaft, the rotary member, and the joint, most of the liquid adhering to the rotary member and the joint scatters by centrifugal force within the rotary member and the joint in the radial direction. In other words, the rotary member and the joint can reduce the amount of the liquid flowing toward the shaft along the rotary member and the joint. The liquid, when flowing to the shaft from the rotary member and the joint, is received by the third outer circumferential surface, and scatters in the radial direction by centrifugal force. In this manner, the motor unit can reduce the amount of the liquid flowing toward the third outer circumferential surface by the rotary member and the joint, and more surely prevent the liquid from entering the first chamber through the first outer circumferential surface.

In the motor unit, as an example, the housing is provided with a fifth chamber communicating with the fourth chamber, the motor includes an electrode at least partially accommodated in the fifth chamber, and the guide member includes a cover being integrated with the peripheral wall to cover the electrode in the fifth chamber. As an example, the liquid received by the inner surface of the third chamber flows into the fifth chamber through the fourth chamber. Owing to the integration of the peripheral wall forming the third chamber and the cover covering the electrode, it is possible to prevent the liquid from adhering to the electrode. Furthermore, as compared with the one including the peripheral wall and the cover separated, the motor unit can prevent the liquid from entering the clearance gap between the guide member and another component, and allows the liquid to smoothly flow from the third chamber to the fifth chamber. In addition, the motor unit can reserve liquid in a wider space by allowing the liquid to flow into the fifth chamber.

In the above description, the word “prevent” is defined as preventing the occurrence of an event, an operation, or influence, for example, or reducing the extent of an event, an operation, or influence. In addition, in the above description, the word “restrict” is defined as preventing movement or rotation, or allowing movement or rotation within a predetermined range and preventing movement or rotation that falls outside the predetermined range, for example.

Heretofore, an embodiment of the present invention has been exemplified, but the above-described embodiment and a modified example merely serve as an example, and are not intended to limit the scope of the invention. The above-described embodiment and a modified can be implemented in other various forms, and various omissions, substitutions, combinations, and changes can be made without departing from the gist of the invention. In addition, configurations and shapes in each embodiment and each modified example can be implemented with being partially replaced.