Motor

Abstract

To suitably fix a guide ring to a stator core.SOLUTION: A motor includes: a case having a case outer wall member and a case lid member; a stator housed in the case; and a guide ring housed in the case. A first end surface of the stator faces the case lid member. A coil wound around the stator core includes a first coil end provided on the first end surface and a second coil end provided on a second end surface. The guide ring is sandwiched and fixed between the case lid member and the first end surface. A coolant supply flow path is provided in the case lid member. An in-core coolant flow path extending from the first end surface to the second end surface is provided inside the stator core. The guide ring is provided with a connection coolant flow path that connects the coolant supply flow path and the internal coolant flow path.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a motor.

[0002] The motor disclosed in Patent Document 1 has a stator core provided with an in-core coolant flow path. In this motor, a ring-shaped cover member (hereinafter referred to as a guide ring) is attached to the stator core. The guide ring is provided with a coolant flow path that supplies coolant to the in-core coolant flow path. The stator core is cooled by the coolant flowing through the in-core coolant flow path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-141703 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, it is necessary to provide an attachment structure (protrusions, locking portions, etc.) for attaching the guide ring to the stator core, which makes the shape of the stator core complex. This makes it difficult to miniaturize the motor. This specification proposes a motor structure that can more suitably fix the guide ring to the stator core. [Means for solving the problem]

[0005] The motor disclosed in this specification includes a case having a cylindrical case outer wall member and a case lid member fixed to an end of the case outer wall member, a stator housed in the case, and a guide ring housed in the case. The stator has a stator core and a coil. The stator core has a cylindrical shape and has a first end face and a second end face located opposite the first end face, and is fixed to the case outer wall member with the first end face facing the case lid member. The coil is wound around the stator core. The coil has a first coil end provided on the first end face and a second coil end provided on the second end face. The guide ring is fixed between the case lid member and the first end face. A coolant supply channel is provided in the case lid member. An internal core coolant channel extending from the first end face to the second end face is provided inside the stator core. The guide ring is provided with a connecting coolant channel connecting the coolant supply channel and the internal coolant channel.

[0006] In this motor, the guide ring is fixed between the case lid member and the first end face of the stator core, which simplifies the structure of the stator core and allows for a more compact motor. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is an exploded perspective view of the motor according to the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the motor of the first embodiment. [Figure 3] 3A and 3B are cross-sectional views of motors according to a second embodiment (FIG. 3A) and a third embodiment (FIG. 3B). DETAILED DESCRIPTION OF THE INVENTION [Example]

[0008] The motor 10 of the first embodiment shown in FIG. 1 includes a rotor 20, a stator 30, a guide ring 60, and a case 50. The rotor 20 is disposed within the central hole of the stator 30 so that the central axis of the shaft 24 of the rotor 20 coincides with the central axis AX of the stator 30. Hereinafter, the direction parallel to the motor axis (i.e., the central axis AX) will be referred to as the axial direction, the direction along a circle centered on the motor axis will be referred to as the circumferential direction, and the direction along the radius of this circle will be referred to as the radial direction. The case 50 includes a case outer wall member 52 and a case lid member 56. The case outer wall member 52 has a cylindrical shape. A flange portion 52a is provided at one end of the case outer wall member 52. The case lid member 56 has a disk shape. A flange portion 56a is provided on the outer periphery of the case lid member 56. As shown in FIG. 2, the flange portion 56a of the case lid member 56 is fastened to the flange portion 52a of the case outer wall member 52 by bolts 72. The case lid member 56 covers one end of the case outer wall member 52. As shown in FIGS.

[0009] A coolant is stored inside the case 50. In this embodiment, the coolant is oil. The oil functions as a coolant and also as a lubricant that lubricates various parts of the motor 10. As shown in FIG. 2, a coolant supply passage 56c is provided in the case lid member 56. The coolant supply passage 56c penetrates the case lid member 56. During operation of the motor 10, the coolant stored in the case 50 is sent to the coolant supply passage 56c by a pump (not shown).

[0010] The stator 30 includes a stator core 32 and a coil 40. The coil 40 is wound around the stator core 32.

[0011] The stator core 32 is composed of multiple electromagnetic steel plates stacked in the axial direction. The stator core 32 has a cylindrical shape concentric with the central axis AX. The stator core 32 is disposed inside the case outer wall member 52 so that the outer peripheral surface of the stator core 32 faces the inner peripheral surface of the case outer wall member 52. The stator core 32 is fixed to the case outer wall member 52 with bolts 70. The stator core 32 has a first end face 32a and a second end face 32b on both sides in the axial direction. The first end face 32a is the end face facing the case lid member 56. The first end face 32a faces the case lid member 56. The second end face 32b is the end face located opposite the first end face 32a. Although not shown, the stator core 32 has multiple teeth on its inner peripheral surface. The coil 40 is wound around each tooth of the stator core 32. The coil 40 has a coil end 42a and a coil end 42b. Note that the coil ends 42a and 42b are shown in a simplified form in FIG. 2. The coil ends 42a and 42b are bent portions of the coil 40 wound around the stator core 32. The coil end 42a is provided on the first end face 32a. The coil end 42a protrudes from the first end face 32a. The coil ends 42a are distributed in an annular pattern on the first end face 32a. A gap is provided between the case lid member 56 and the first end face 32a, and the coil ends 42a are arranged within this gap. The coil end 42b is provided on the second end face 32b. The coil end 42b protrudes from the second end face 32b. The coil ends 42b are distributed in an annular pattern on the second end face 32b.

[0012] A plurality of in-core coolant flow paths 39 are provided inside the stator core 32. Note that, although one in-core coolant flow path 39 is shown in the cross section of FIG. 2, other in-core coolant flow paths 39 are provided at positions different from those shown in FIG. 2. Each in-core coolant flow path 39 extends along the axial direction. One end of each in-core coolant flow path 39 opens to the first end face 32a, and the other end of each in-core coolant flow path 39 opens to the second end face 32b. The multiple in-core coolant flow paths 39 are provided dispersed in the circumferential direction.

[0013] As described above, rotor 20 has shaft 24 and is disposed in the center hole of stator 30 so that the center axis of shaft 24 coincides with the center axis AX of stator 30. Shaft 24 of rotor 20 is inserted into through-hole 56b provided in the center of case lid member 56. Rotor 20 is rotatably supported by bearings and the like (not shown).

[0014] The guide ring 60 has a ring shape. The guide ring 60 is disposed so that its central axis coincides with the central axis AX of the stator 30. The guide ring 60 is disposed axially between the first end face 32a of the stator core 32 and the case lid member 56. One end of the guide ring 60 contacts the first end face 32a of the stator core 32, and the other end of the guide ring 60 contacts the case lid member 56. The guide ring 60 is fixed in the axial direction by being sandwiched between the case lid member 56 and the first end face 32a. A spigot joint 56d provided on the case lid member 56 positions the guide ring 60 radially. The coil end 42a is disposed on the inner circumferential side of the guide ring 60.

[0015] A connecting coolant flow passage 62 is provided within the guide ring 60. The connecting coolant flow passage 62 extends in a ring shape along the guide ring 60. The connecting coolant flow passage 62 is connected to the coolant supply flow passage 56c of the case lid member 56. The connecting coolant flow passage 62 is connected to each of the in-core coolant flow passages 39 at the first end surface 32a. That is, the connecting coolant flow passage 62 connects the coolant supply flow passage 56c to each of the in-core coolant flow passages 39. Furthermore, multiple coolant discharge flow passages 64 are provided within the guide ring 60. Note that while one coolant discharge flow passage 64 is shown in the cross section of FIG. 2, other coolant discharge flow passages 64 are provided at positions different from those shown in FIG. 2. Each coolant discharge flow passage 64 branches from the connecting coolant flow passage 62 and extends to the inner circumferential surface of the guide ring 60. Each coolant discharge flow passage 64 discharges coolant radially inward of the guide ring 60. The coolant discharge flow passages 64 are provided in a circumferentially dispersed manner.

[0016] When the motor 10 is operating, a pump (not shown) supplies coolant to the coolant supply passage 56c of the case lid member 56. The coolant flows as indicated by the dashed arrows in FIG. 2 . That is, the coolant flows from the coolant supply passage 56c to the connecting coolant passage 62. A portion of the coolant in the connecting coolant passage 62 is discharged from each coolant discharge passage 64 toward the coil end 42a, thereby cooling the coil end 42a. The coolant in the connecting coolant passage 62 is also supplied to each in-core coolant passage 39. In each in-core coolant passage 39, the coolant flows from the first end face 32a to the second end face 32b. The coolant flowing through each in-core coolant passage 39 cools the stator core 32. The coolant in each in-core coolant passage 39 is discharged from the second end face 32b. The coolant discharged from the second end face 32b splashes on the coil end 42b, thereby cooling the coil end 42b. In this way, the motor 10 can effectively cool the stator core 32 and the coils 40.

[0017] As described above, the case lid member 56 is fixed to the case outer wall member 52 by bolts 72 extending along the axial direction of the motor 10. The guide ring 60 is sandwiched and fixed between the case lid member 56 and the first end face 32a by the pressure generated by fastening the bolts 72. Therefore, pressure is applied to the guide ring 60 along the axial direction. Therefore, pressure is applied to the contact surface between the guide ring 60 and the case lid member 56 and the contact surface between the guide ring 60 and the first end face 32a, preventing leakage of coolant from these contact surfaces. In particular, in the range R (radial range) shown in FIG. 2 , the guide ring 60 extends from the case lid member 56 to the first end face 32a, making it easy for pressure to be applied to the guide ring 60. Therefore, leakage of coolant from each contact surface can be effectively prevented. If necessary, a seal member 80 may be provided at the interface between the guide ring 60 and the case lid member 56. Preventing coolant leakage allows an appropriate amount of coolant to flow through each coolant flow path, efficiently cooling the motor 10. Furthermore, this guide ring fixing structure allows the shape of the stator core 32 to be simplified, thereby enabling the motor 10 to be made more compact.

[0018] Furthermore, in the motor 10 of the first embodiment, each in-core coolant flow passage 39 extends linearly from the first end face 32a to the second end face 32b, so that pressure loss is unlikely to occur in each in-core coolant flow passage 39. [Example]

[0019] In the motor of Example 2 shown in Fig. 3a, a coil spring 82 is provided axially between the guide ring 60 and the case lid member 56. The coil spring 82 can pressurize the guide ring 60 toward the first end face 32a, thereby applying appropriate pressure to the contact surface between the guide ring 60 and the first end face 32a. This effectively prevents leakage of the coolant. [Example]

[0020] In the motor of Example 3 shown in FIG. 3b, a pressure chamber 63 is provided inside the guide ring 60. The pressure chamber 63 is connected to the connecting coolant flow path 62. A portion of the wall of the pressure chamber 63 is formed by the inner surface of the case lid member 56 (more specifically, the inner surface facing the first end face 32a). The pressure chamber 63 is filled with coolant. The area A1 of the area where the case lid member 56 receives pressure from the coolant in the pressure chamber 63 is larger than the area A2 of the area where the stator core 32 receives pressure from the coolant in the guide ring 60. In the motor of Example 3, when coolant is supplied to the connecting coolant flow path 62 by the pump, the supply pressure of the pump is applied to the coolant in the pressure chamber 63. The pressure in the pressure chamber 63 then pressurizes the guide ring 60 toward the first end face 32a. This allows appropriate pressure to be applied to the contact surface between the guide ring 60 and the first end face 32a. This effectively prevents coolant leakage.

[0021] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings simultaneously achieves multiple objectives, and achieving one of these objectives itself has technical utility. [Explanation of symbols]

[0022] 20:Rotor 32: Stator core 32a: First end surface 32b: Second end surface 39: Coolant flow path in the core 42a: Coil end 42b: Coil end 52: Case outer wall material 56: Case cover material 56c: Coolant supply channel 60: Guide ring 62: Connecting coolant flow path

Claims

[Claim 1] A motor, a case having a cylindrical outer wall member and a case lid member fixed to an end of the outer wall member; a stator housed in the case; a guide ring housed in the case; and The stator is a stator core having a cylindrical shape, a first end surface and a second end surface located opposite to the first end surface, and fixed to the case outer wall member with the first end surface facing the case lid member; a coil wound around the stator core, the coil having a first coil end provided on the first end surface and a second coil end provided on the second end surface; and the guide ring is fixed between the case lid member and the first end surface, a coolant supply passage is provided in the case lid member, an inner-core coolant flow path extending from the first end surface to the second end surface is provided inside the stator core; a connecting coolant flow path that connects the coolant supply flow path and the internal coolant flow path is provided in the guide ring; Motor.

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