Rotating electrical machine

Abstract

Provided is a rotating electric machine having improved cooling performance, including a stator (12) having a stator core (24) and a stator coil (26), a first bracket (16) covering one end surface of the stator core, a second bracket (18) covering the other end surface of the stator core, and a rotor (28). A first flow path forming portion (40) provided on the outer periphery of the stator core has a first flow path (F1) extending from one end to the other end in the axial direction of the stator core, and a second flow path (F2) provided on the outer side in the radial direction of the first flow path and extending from one end to the other end in the axial direction of the stator core. The first bracket includes a ring-shaped peripheral wall (16a) having an open end opposed to one end surface of the stator core, a bottom wall (16b) opposed to one end surface of the stator core at a distance, and a second flow path forming portion (48) formed by a portion of the peripheral wall. The second flow path forming portion forms an external air flow path (RA) and an internal air flow path (RI).

Description

[0001] Citation of priority-based applications and related applications

[0002] This application is based on Japanese Patent Application 2021-153136 (filed on September 21, 2021) and claims the benefit of its priority. The entire contents of that application are incorporated herein by reference. Technical Field

[0003] The embodiments described herein relate to rotary electric machines. Background Technology

[0004] In recent years, permanent magnet rotary motors with permanent magnets arranged on the rotor's magnetic poles have been proposed. Furthermore, rotary motors for vehicle drives require miniaturization and high output. With the increase in output, the temperature rise of the stator coils and permanent magnets may become a problem. Therefore, it is necessary to improve the cooling performance of rotary motors. Summary of the Invention

[0005] The objective of embodiments of the present invention is to provide a rotary motor with improved cooling performance.

[0006] According to an embodiment, a rotary electric motor includes: a stator having a cylindrical stator core having a first end face at one end in the axial direction and a second end face at the other end in the axial direction, and an outer peripheral surface; a stator coil mounted on the stator core; and a first flow path forming portion provided on the outer periphery of the stator core, the first flow path forming portion forming a first flow path extending from one end in the axial direction of the stator core to the other end, and a second flow path located radially outside the first flow path and extending from one end in the axial direction of the stator core to the other end; a first bracket having an annular peripheral wall having an open end facing the first end face, a bottom wall spaced apart from the first end face, and a second flow path forming portion formed by a portion of the peripheral wall; and a second bracket having an annular peripheral wall having an open end facing the second end face, and a bottom wall spaced apart from the second end face. The second flow path forming portion of the first bracket includes: a first end wall extending radially from the open end of the peripheral wall and having a circumferential width; a pair of first side walls extending axially from one end and the other end of the first end wall to the bottom wall, respectively, and erected radially and spaced apart from each other in the circumferential direction; a first bottom wall located between the pair of first side walls, extending axially from the end of the first end wall at the open end side to the bottom wall and having a first circumferential width; a first partition wall located between the pair of first side walls, extending axially from the first end wall to the bottom wall and having a first circumferential width, and spaced apart from the first bottom wall in the radial direction; a first top wall located between the pair of first side walls, extending axially from the end of the first end wall at the extended end side to the bottom wall and having a first circumferential width, and spaced apart from the first partition wall in the radial direction; a first flow path forming portion includes: a first flow path forming portion ... An outlet is formed on the first end wall and has a predetermined circumferential width, opposite one end of the first flow path; a second flow outlet is formed on the first end wall and has a predetermined circumferential width, located radially outward relative to the first flow outlet and opposite one end of the second flow path; a first flow inlet is formed on the first bottom wall and located adjacent to the bottom wall, having a first circumferential width; a second flow inlet is formed on the first bottom wall and located on the side of the first end wall relative to the first flow inlet, having a second circumferential width smaller than the first width; a flow port is formed on the first partition wall and located opposite the second flow inlet, having a third circumferential width smaller than the first width; and a cylindrical second partition wall is located between the first bottom wall and the first partition wall, having one end connected to the first bottom wall and located around the second flow inlet, and another end connected to the first partition wall and located around the flow port.An external gas flow path connecting the first inlet and the first outlet is formed by the first bottom wall, the first partition wall, the pair of first side walls, and the second partition wall. An internal gas flow path connecting the second inlet and the second outlet is formed by the first partition wall, the first top wall, the pair of first side walls, and the second partition wall. Attached Figure Description

[0007] Figure 1 This is a perspective view showing the appearance of the rotary electric motor according to the embodiment.

[0008] Figure 2 This is an exploded perspective view of the rotary motor, showing the first bracket and the cover plate separately.

[0009] Figure 3 It is along Figure 1 A cross-sectional view of the rotary motor of line AA.

[0010] Figure 4 It is along Figure 3 A cross-sectional view of the first bracket portion of line CC.

[0011] Figure 5 It is along Figure 3 A cross-sectional view of the first bracket portion of line DD.

[0012] Figure 6 It is along Figure 3 A cross-sectional view of the rotary motor described in line BB.

[0013] Figure 7 This is a cross-sectional view of the rotary motor, showing a portion of its longitudinal section.

[0014] Figure 8 It is a three-dimensional diagram schematically showing the external and internal gas flow paths of the first bracket.

[0015] Figure 9 It includes along Figure 8 A three-dimensional view of the cross-section of the flow path forming part of the FF line.

[0016] Figure 10 It includes along Figure 8 A three-dimensional view of the cross-section of the flow path forming part of the GG line.

[0017] Figure 11 It includes along Figure 8 A three-dimensional view of the cross-section of the flow path forming part of line HH.

[0018] Figure 12 It includes along Figure 3 A cross-sectional view of the second bracket portion of the EE line. Detailed Implementation

[0019] The rotary motor of the embodiment will be described below with reference to the accompanying drawings.

[0020] Furthermore, this disclosure is merely one example, and appropriate modifications that can be readily conceived by those skilled in the art while maintaining the spirit of the invention are of course included within the scope of this invention. In all embodiments, common components are labeled with the same reference numerals, and repeated descriptions are omitted. Moreover, the figures are schematic diagrams used to facilitate the implementation and understanding of the embodiments; their shapes, sizes, proportions, etc., may differ from actual devices, but can be appropriately designed and modified with reference to the following description and known techniques.

[0021] (Implementation Method)

[0022] Figure 1 This is a perspective view showing the appearance of the rotary electric motor according to the embodiment. Figure 2 This is an exploded perspective view of the rotary motor, showing the first bracket and the cover plate separately. Figure 3 It is along Figure 1 A cross-sectional view of a rotating electric machine with line AA. In the following description, the direction of the central axis C1 of the rotating electric machine is called the axial direction, the direction orthogonal to the central axis C1 is called the radial direction, and the direction around the central axis C1 is called the circumferential direction.

[0023] like Figure 1 as well as Figure 2 As shown, the rotary motor 10 is configured as a so-called fully enclosed rotary motor. The rotary motor 10 includes a stator 12, a first core pressing member 14a fixed to one axial end face of the stator 12, a second core pressing member 14b fixed to the other axial end face of the stator 12, a bowl-shaped first bracket 16 fixed to the first core pressing member 14a and covering one end side (drive side) of the stator 12, a bowl-shaped second bracket 18 fixed to the second core pressing member 14b and covering the other end side (non-drive side) of the stator 12, and multiple, for example, four cover plates 20 fixed to the outer periphery of the stator 12. The first bracket 16 and the second bracket 18, together with the stator 12, constitute an internally sealed housing (outer shell). Bearing seats with built-in bearings B1 and B2 (described later) are mounted on the first bracket 16 and the second bracket 18. Inside the housing, a rotor 28 (described later) is provided, which rotates freely relative to the stator 12. The two ends of the rotor's rotating shaft are supported by bearings and are rotatably configured about the central axis C1.

[0024] like Figure 3As shown, the stator 12 has a generally annular or cylindrical stator core 24 and a stator coil 26 wound around the stator core. The stator core 24 is constructed by stacking multiple sheets of magnetic material, such as annular metal sheets (electromagnetic steel sheets) P1 made of silicon steel plates, along the axial direction. The stator coil 26 is disposed in multiple slots of the stator core 24 and has coil ends 27a and 27b extending axially from one end face 24a and the other end face 24b of the stator core 24. A first core pressing member 14a and a second core pressing member 14b are disposed overlapping one end face and the other end face of the stator core 24 along the axial direction, clamping the stator core 24 from both sides along the axial direction.

[0025] The first bracket 16 is formed into a bowl shape, for example, by means of aluminum or aluminum alloy, and integrally has a generally cylindrical peripheral wall 16a and a disc-shaped bottom wall 16b that seals one end of the peripheral wall 16a. The first bracket 16 is coaxially configured with respect to the central axis C1 and covers the drive side of the stator 12 by fixing one end of the peripheral wall 16a to the first core pressing member 14a. The bottom wall 16b is axially spaced from one end face of the stator core 24. The annular first bearing bracket 53 is fastened to the center of the bottom wall 16b by bolts. The first bearing seat 54, which houses the first bearing B1, is fastened to the center of the first bearing bracket 53. Around the first bearing B1, the first bearing bracket 53 is provided with a plurality of air inlets 55.

[0026] Figure 4 It is along Figure 3 The figure shows a cross-sectional view of the first bracket 16 of the bearing CC. As shown, the first bearing bracket 53 is provided with a plurality of air inlets 55. The plurality of air inlets 55 are located around the rotating shaft 30 and are arranged at equal intervals in the circumferential direction.

[0027] like Figure 3 As shown, the second bracket 18 is formed into a generally bowl shape, for example, from aluminum or aluminum alloy, and integrally has a generally cylindrical peripheral wall 18a, a disc-shaped bottom wall 18b that seals one end of the peripheral wall 18a, and an annular partition wall 18c located on the inner surface of the bottom wall 18b and spaced apart from the peripheral wall 18a. The second bracket 18 is coaxially arranged with the central axis C1 and covers the non-drive side of the stator 12 by fixing one open end of the peripheral wall 18a to the second core pressing member 14b. A second bearing seat 62, which houses the second bearing B2, is fastened to the center of the bottom wall 18b. Around the second bearing B2, a plurality of air inlets 55 are provided in the bottom wall 18b.

[0028] The rotor 28 has a rotating shaft 30, a rotor core 32, and multiple permanent magnets M embedded in the rotor core 32. The rotating shaft 30 is coaxially disposed within the housing with the central axis C1, and one end of the shaft is rotatably supported by a first bearing B1 and a second bearing B2, respectively. One end of the rotating shaft 30 extends outward through the bearing B1, forming the drive end 30a.

[0029] The rotor core 32 is constructed by stacking multiple annular metal sheets (electromagnetic steel sheets) P2 of magnetic material, such as silicon steel sheets, along the axial direction, forming a generally cylindrical shape. The rotor core 32 is mounted approximately at the center of the rotating shaft 30, inside the stator core 24, and coaxially with the central axis C1. The outer circumferential surface of the rotor core 32 faces the inner circumferential surface of the stator core 24 with an air gap. The axial length of the rotor core 32 is approximately equal to the axial length of the stator core 24, and the rotor core 32 spans its entire length opposite the stator core 24.

[0030] A plurality of magnet insertion holes 50 extending axially are formed on the outer periphery of the rotor core 32 and are arranged at circumferential intervals. The magnet insertion holes 50 are formed by penetrating the rotor core 32 axially and opening at both end faces of the rotor core 32. A rectangular plate-shaped permanent magnet M is filled into each magnet insertion hole 50. The permanent magnet M extends across the entire axial length of the rotor core 32.

[0031] The rotor core 32 is supported by a pair of circular core pressing members 28a and 28b mounted on the rotating shaft 30, which clamp it from both axial end faces. The core pressing members 28a and 28b are formed in annular shape, and their outer diameter is formed to be slightly smaller than the outer diameter of the rotor core 32.

[0032] A first fan FA is installed on the rotating shaft 30 between the rotor core 32 and the first bearing B1, and rotates freely integrally with the rotating shaft 30. A second fan FB is installed on the rotating shaft 30 between the rotor core 32 and the second bearing B2, and rotates freely integrally with the rotating shaft 30.

[0033] The first fan FA is configured as a centrifugal fan, generating radial airflow through rotation. The first fan FA has a fan body 70a in the shape of a trumpet or fan. The fan body 70a is fixed to the rotating shaft 30, extending radially outward from the rotor core 32 towards the first bracket 16. The outer peripheral edge of the fan body 70a is located inside the peripheral wall 16a of the first bracket 16, and is arranged radially with a portion of the peripheral wall 16a. This outer peripheral edge and the inner peripheral part of the peripheral wall 16a engage with each other through a small annular gap. The small annular gap is formed into two approximately concave-convex sections, creating a labyrinthine structure X.

[0034] The internal space of the first bracket 16 is divided by the fan body 70a into an outer space OA defined between the first fan FA and the bottom wall 16b, and an inner space IA defined between the first fan FA and the stator 12. The air inlet 55 of the first bracket 16 communicates with the outer space OA.

[0035] Figure 5 It is along Figure 3 The figure shows a cross-sectional view of the first bracket 16 portion of the line DD. As shown, the first fan FA has an annular inner cover 72 disposed opposite to the inner surface of the stator core 24 of the fan body 70a with a gap, multiple inner blades 73 disposed between the inner surface of the fan body 70a and the inner cover 72, and multiple outer blades 74 disposed on the outer surface of the fan body 70a on the side of the first bearing B1. The inner blades 73 are arranged at certain intervals in the circumferential direction and are located in the inner space IA. The outer blades 74 are arranged at certain intervals in the circumferential direction and are located in the outer space OA.

[0036] like Figure 3 As shown, the second fan FB is configured as a centrifugal fan, generating radial airflow through rotation. The second fan FB has a fan body 76a in the shape of a trumpet or fan. The fan body 76a is fixed to the rotating shaft 30 via a core pressing member 28b, extending radially outward from the rotor core 32 side towards the bottom wall 18b of the second bracket 18. The outer peripheral edge of the fan body 76a is located inside the partition wall 18c of the second bracket 18, and is arranged radially with the partition wall 18c. This outer peripheral edge and the inner peripheral edge of the partition wall 18c engage with each other through a small annular gap. The small annular gap is formed into two approximately concave-convex sections, creating a labyrinthine structure X.

[0037] The internal space of the second bracket 18 is divided by the fan body 76a and the partition wall 18c into an outer space OA defined between the second fan FB and the bottom wall 18b, and an inner space IA defined between the second fan FB and the stator 12. The air inlet 65 and the exhaust outlet of the second bracket 18 are connected to the outer space OA.

[0038] The second fan FB has an annular outer casing 77 disposed opposite to the outer surface of the second bearing B2 side of the fan body 76a with a gap, and multiple outer blades 78 disposed between the fan body 76a and the outer casing 77. The outer blades 78 are arranged at certain intervals in the circumferential direction and are located in the outer space OA.

[0039] Figure 6 It is along Figure 3 Cross-sectional views of the stator and rotor of the BB line.

[0040] like Figure 6As shown, in this embodiment, the rotor 28 is configured with multiple magnetic poles, for example, six magnetic poles. Two permanent magnets M are embedded in the rotor core 32 for each magnetic pole. When the axis passing through the central axis C1 and extending radially from the center of the circumferential magnetic pole is designated as the magnetic pole center axis (d-axis), magnet insertion holes 50 are provided on both sides of each d-axis in the circumferential direction. The magnet insertion holes 50 have a generally rectangular cross-sectional shape corresponding to the shape of the permanent magnets M, and are inclined relative to the d-axis. Two permanent magnets M are respectively filled and disposed within the magnet insertion holes 50. The permanent magnets M are fixed to the rotor core 32, for example, by adhesive.

[0041] The permanent magnet M is, for example, a long, narrow plate with a rectangular cross-section, and is disposed along the entire axial length of the rotor core 32. Each magnet insertion hole 50 has a generally rectangular filling area filled with the permanent magnet M, an inner circumferential gap 50a bulging from one end of the filling area toward the d-axis, and an outer circumferential gap 50b bulging from the other end of the filling area toward the outer circumferential surface of the rotor core 32. The two magnet insertion holes 50 and the two permanent magnets M are adjacent to each other across the d-axis at one end, and their outer circumferential ends are separated from the d-axis and located near the outer circumferential surface of the rotor core 32, arranged in a generally V-shape. As described later, cooling air can flow through the inner circumferential gap 50a and the outer circumferential gap 50b of each magnet insertion hole 50.

[0042] A plurality of slots 36 are formed on the inner circumference of the stator core 24. The plurality of slots 36 are arranged at equal intervals in the circumferential direction. Each slot 36 opens on the inner circumferential surface of the stator core 24 and extends radially from the inner circumferential surface. Each slot 36 extends across the entire axial length of the stator core 24. By forming a plurality of slots 36, the inner circumference of the stator core 24 forms a plurality of teeth 38 facing the rotor 28.

[0043] The stator coil 26 is, for example, composed of multiple flat conductors. Two stator coils 26 are arranged in each slot 36 and wound around the teeth 38. Current flows through the stator coil 26, thereby forming a predetermined linked magnetic flux in the stator 12 (teeth 38).

[0044] In this embodiment, the stator 12 has multiple flow path forming portions (first flow path forming portions) 40 located at, for example, four locations on its outer periphery. The four flow path forming portions 40 are equidistant in the circumferential direction, for example, at positions separated by 90 degrees. Each flow path forming portion 40 has a grid-like rib 42 extending radially outward from the outer periphery of each electromagnet plate P1 constituting the stator core 24. The rib 42 has a generally arc-shaped main rib 42a. The main rib 42a extends radially outward from one location on the outer periphery of the electromagnet plate P1 to other locations separated in the circumferential direction, and is spaced apart from the outer periphery. A first flow path F1 is defined between the main rib 42a and the outer periphery of the electromagnet plate P1. In addition, the rib 42 integrally includes a plurality of first rectifier ribs 42b extending radially from the outer periphery of the electromagnetic steel plate P1 to the main rib 42a and dividing the first flow path F1 into a plurality of multiple circumferentially, and a plurality of second rectifier ribs 42c extending radially outward from the outer periphery of the main rib 42a.

[0045] By stacking multiple electromagnetic steel plates P1 concentrically, the ribs 42 are arranged side by side in the axial direction. This forms a first flow path F1 that extends continuously in the axial direction between the ribs 42 and the outer peripheral surface of the stator core 24. The first rectifier rib 42b is located within the first flow path F1 and functions as a rectifier plate.

[0046] The flow path forming section 40 has a cover plate 20. The cover plate 20 is disposed covering the rib 42, and the two side edges of the cover plate 20 are fixed to, for example, welded to the outer periphery of the stator core 24. Opposite end edges of the cover plate 20 are respectively welded to the first core pressing member 14a and the second core pressing member 14b. A second flow path F2 is defined by the outer peripheral surface of the stator core 24, the outer peripheral surface of the main rib 42a, and the inner surface of the cover plate 20. The second flow path F2 extends continuously axially from one end of the stator core 24 to the other end. The second rectifier rib 42c is located within the second flow path F2 and can function as a rectifier plate.

[0047] Figure 7 This is a three-dimensional view of a rotating electric motor, showing a longitudinal section of a portion thereof. For example... Figure 7 As shown, in this embodiment, multiple electromagnetic steel plates P2 constituting the stator core 24 are stacked around the central axis C1, staggered by several degrees in the direction of rotation. Consequently, the first flow path F1 of each flow path forming section 40 extends at a predetermined angle relative to the axial direction. Similarly, multiple second rectifier ribs 42c located within the second flow path F2 extend at a predetermined angle relative to the axial direction.

[0048] like Figure 2As shown, the first core pressing member 14a and the second core pressing member 14b of the stator 12 each have four flow ports 44 located at four positions on their outer periphery. The four flow ports 44 are located at equal intervals in the circumferential direction, for example, at positions separated by 90 degrees. Each flow port 44 includes a first flow port 44a and a second flow port 44b, each formed by an arc-shaped elongated hole extending circumferentially. The first and second flow ports 44a and 44b are arranged radially; in one example, the first flow port 44a is located radially inner, and the second flow port 44b is located radially outer. Alternatively, the first flow port 44a and the second flow port 44b may each be configured as multiple flow ports divided circumferentially.

[0049] like Figure 3 as well as Figure 7 As shown, with the first core pressing member 14a and the second core pressing member 14b installed on the end face of the stator core 24, the first flow port 44a of the first core pressing member 14a is located opposite one end of the first flow path F1 corresponding to the stator 12 and is connected to the first flow path F1. The second flow port 44b of the first core pressing member 14a is located opposite one end of the second flow path F2 corresponding to the stator 12 and is connected to the second flow path F2. Similarly, the first flow port 44a of the second core pressing member 14b is located opposite the other end of the first flow path F1 corresponding to the stator 12 and is connected to the first flow path F1. The second flow port 44b of the second core pressing member 14b is located opposite the other end of the second flow path F2 corresponding to the stator 12 and is connected to the second flow path F2.

[0050] like Figure 1 As shown, the first bracket 16 has flow path forming protrusions (second flow path forming portions) 48 at multiple locations on the peripheral wall 16a, specifically at four locations, with a predetermined width and thickness. The four flow path forming protrusions 48 are circumferentially spaced at equal intervals, for example, separated by 90 degrees. Each flow path forming protrusion 48 extends axially from the opening end of the peripheral wall 16a to the bottom wall 16b, and has a predetermined width in the circumferential direction. The flow path forming protrusions 48 are respectively opposed to the flow path forming portions 40 of the stator 12. In the flow path forming protrusions 48, the external gas flow path and the internal gas flow path, described later, are formed in a mutually separated state.

[0051] Between two adjacent flow path forming protrusions 48, flanges 52 are provided at the opening ends of the peripheral wall 16a. The outer diameter and shape of the peripheral wall 16a, including the flow path forming protrusions 48 and the flanges 52, are approximately the same as the outer diameter and shape of the first core pressing member 14a. The inner diameter of the peripheral wall 16a is set to be slightly smaller than the outer diameter of the stator core 24 (excluding the outer diameter of the flow path forming portion 40).

[0052] The first bracket 16 is fixed to the first core pressing member 14a at positions where the protrusions 48 in the four flow paths are respectively opposite to the flow ports 44 of the first core pressing member 14a. Here, the flange 52 is fastened to the first core pressing member 14a by bolts.

[0053] The second bracket 18 has flow path forming protrusions (third flow path forming portions) 58 at multiple locations on the peripheral wall 18a, specifically at four locations, with a predetermined width and thickness. The four flow path forming protrusions 58 are located at equal intervals in the circumferential direction, for example, at positions separated by 90 degrees. Each flow path forming protrusion 58 extends axially from one end of the peripheral wall 18a to the other, having a predetermined width in the circumferential direction. In the flow path forming protrusions 58, the external gas flow path and the internal gas flow path, described later, are formed in a mutually separated state.

[0054] Between two adjacent flow path forming protrusions 58, flanges 61 are provided at the opening ends of the peripheral wall 18a. The outer diameter and shape of the peripheral wall 18a, including the flow path forming protrusions 58 and the flanges 61, are approximately the same as the outer diameter and shape of the second core pressing member 14b. The inner diameter of the peripheral wall 18a is set to be slightly smaller than the outer diameter of the stator core 24 (excluding the outer diameter of the flow path forming portion 40).

[0055] The second bracket 18 has flow path forming protrusions (third flow path forming portions) 58 of a predetermined width and thickness located at multiple positions on the peripheral wall 18a, specifically at four locations. The four flow path forming protrusions 58 are located at equal intervals in the circumferential direction, for example, at positions separated by 90 degrees. Each flow path forming protrusion 58 extends axially from the opening end of the peripheral wall 18a to the bottom wall 18b, and has a predetermined width in the circumferential direction. In the flow path forming protrusions 58, the external gas flow path and the internal gas flow path (described later) are formed in a mutually separated state. The second bracket 18 is fixed to the second core pressing member 14a at positions where the four flow path forming protrusions 58 are respectively opposite to the flow opening 44 of the second core pressing member 14b. Here, the flange 61 is fastened to the second core pressing member 14b by bolts.

[0056] Next, the configuration of the flow path forming protrusion 48 of the first bracket 16 will be explained.

[0057] Figure 8This is a perspective view schematically showing the external gas flow path and the internal gas flow path of the flow path forming protrusion 48 formed on the first bracket. As shown, a first external gas flow path RA and a first internal gas flow path RI are formed within the flow path forming protrusion 48. The flow path forming protrusion 48 has a first inlet IP1 that opens into the outer space OA of the first bracket 16, and a first outlet OP1 that faces one end of the first flow path F1 of the stator 12. The first external gas flow path RA connects the first inlet IP1 and the first outlet OP1. The first external gas flow path RA extends axially from the first inlet IP1 to the first outlet OP1. The first external gas flow path RA has a first width W1 in the circumferential direction. At the midpoint of the axial direction, the first external gas flow path RA has a narrow portion WS whose circumferential width is narrower than other portions.

[0058] The flow path forming protrusion has a second inlet IP2 with an opening in the inner space IA of the first bracket 16, and a second outlet OP2 opposite to one end of the second flow path F2 of the stator 12. The second inlet IP2 and the narrow portion WS of the first external gas flow path RA are arranged side by side in the circumferential direction. The second outlet OP2 is located radially outward relative to the first outlet OP1. A first internal gas flow path RI connects the second inlet IP2 and the second outlet OP2. The first internal gas flow path RI extends radially outward from the second inlet IP2 across the first external gas flow path RA, and also extends axially to the second outlet OP2. The axially extending portion of the first internal gas flow path RI has a first width W1 in the circumferential direction and is located radially outward relative to the first external gas flow path RA.

[0059] Next, the structure of the wall portion forming the first external gas flow path RA and the first internal gas flow path RI will be described. Figure 9 It means along Figure 8 A three-dimensional view of the cross-section of the convex portion formed by the flow path of the FF line. Figure 10 It means along Figure 8 A three-dimensional view of the cross-section of the convex portion formed by the flow path of the GG line. Figure 11 It means along Figure 6 A three-dimensional view of the cross-section of the convex portion formed by the flow path of line HH.

[0060] like Figure 9As shown, the flow path forming protrusion 48 has a first end wall 48a extending radially from the open end of the peripheral wall 16a and having a circumferential width W; a pair of first side walls 48b, each radially erected on the peripheral wall 16a and extending axially from one end and the other end of the first end wall 48a to the bottom wall 16b, and spaced apart circumferentially by a first width W1; and a first bottom wall 48c, located between the pair of first side walls 48b and extending axially from the end of the first end wall 48a on the side of the open end to the bottom wall 16b, having a circumferential width W1. In this embodiment, the first bottom wall 48c is formed by a portion of the peripheral wall 16a of the first bracket 16.

[0061] A first outlet OP1 and a second outlet OP2 are formed on the first end wall 48a. The first outlet OP1 and the second outlet OP2 are elongated holes extending circumferentially and having a predetermined circumferential width (<W1). The first outlet OP1 is located on the opening end side of the peripheral wall 16a, and the second outlet OP2 is located radially outward relative to the first outlet OP1.

[0062] The flow path forming protrusion 48 has a first partition wall 48d located between a pair of first sidewalls 48b and extending axially from the midpoint of the first end wall 48a to the bottom wall 16b, and radially spaced from the first bottom wall 48c; and a first top wall 48e located between the pair of first sidewalls 48b and extending axially from the protruding end of the first end wall 48a to the bottom wall 16b, and radially spaced from the first partition wall 48d. The first partition wall 48d and the first top wall 48e each have a circumferential first width W1. The end of the first top wall 48e on the bottom wall 16b side is connected to the end of the first partition wall 48d on the bottom wall 16b side.

[0063] like Figure 9 As shown, a first inlet IP1 and a second inlet IP2 are formed in the first bottom wall 48c. The first inlet IP1 is located adjacent to the bottom wall 16b. The first inlet IP1 is an elongated hole extending circumferentially and has a second width W2 in the circumferential direction. The second width W2 is slightly smaller than the first width W1 of the first bottom wall 48c. The second inlet IP2 is located on the side of the first end wall 48a relative to the first inlet IP1 and is located adjacent to one of the side walls 48b. The second inlet IP2 is an elongated hole extending circumferentially from one side wall 48b to the other side wall 48b and has a third width W3 in the circumferential direction. The third width W3 is smaller than the second width W2, for example, set to about 1 / 2 of the first width W1.

[0064] like Figure 10 as well as Figure 11As shown, a flow port CP1 is formed in the first partition wall 48d. The flow port CP1 is located radially opposite to the second inlet IP2. The flow port CP1 is an elongated hole extending circumferentially from one sidewall 48b to the other sidewall 48b, having a third circumferential width W3.

[0065] The flow path forming protrusion 48 has a cylindrical second partition wall 48f located between the first bottom wall 48c and the first partition wall and extending radially. One end of the second partition wall 48f is connected to the first bottom wall 48c and located around the second inlet IP2, and the other end of the second partition wall 48f is connected to the first partition wall 48d and located around the flow port CP1. In this embodiment, a portion of the second partition wall 48f is formed by a side wall 48b. The flow path connecting the second inlet IP2 and the flow port CP1 is defined through the inner circumferential surface of the second partition wall 48f.

[0066] In the flow path forming protrusion 48 constructed above, a first external gas flow path RA connecting the first flow inlet IP1 and the first flow outlet OP1 is defined by the first bottom wall 48c, the first partition wall 48d, a pair of first side walls 48b, and the second partition wall 48f. A first internal gas flow path IR connecting the second flow inlet IP2 and the second flow outlet OP2 is defined by the first partition wall 48d, the first top wall 48e, a pair of first side walls 48b, and the second partition wall 48f.

[0067] like Figure 5 As shown, the four flow path forming protrusions 48 of the first bracket 16 are located at equal intervals in the circumferential direction, for example, at positions separated by 90 degrees. In this embodiment, the narrow portion WS of the first external gas flow path RA of one flow path forming protrusion 48 is formed adjacent to one sidewall 48b, and the narrow portions WS of the other flow path forming protrusions 48 adjacent in the circumferential direction are formed adjacent to the other sidewall 48b. That is, two flow path forming protrusions adjacent in the circumferential direction are formed in a left-right symmetrical shape with respect to the virtual line L1 passing through the space between these two flow path forming protrusions 48 and the central axis C1.

[0068] like Figure 3As shown, with the first bracket 16 fixed to the first core pressing member 14a, the first outlet OP1 of each flow path forming protrusion 48 is opposite to the first flow port 44a of the first core pressing member 14a and one end of the first flow path F1 of the stator 12. Thus, the first external gas flow path RA of the flow path forming protrusion 48 is connected to one end of the first flow path F1 via the first outlet OP1 and the first flow port 44a. The second outlet OP2 of each flow path forming protrusion 48 is opposite to the first flow port 44b of the first core pressing member 14a and one end of the second flow path F2 of the stator 12. Thus, the first internal gas flow path RI of the flow path forming protrusion 48 is connected to one end of the second flow path F2 via the second outlet OP2 and the second flow port 44b.

[0069] The first inlet IP1 of each flow path forming protrusion 48 opens in the outer space OA of the first bracket 16, and the first external gas flow path RA communicates with the outer space OA through the first inlet IP1. The second inlet IP2 of each flow path forming protrusion 48 opens in the inner space IA of the first bracket 16, and the first internal gas flow path RI communicates with the inner space IA through the second inlet IP2.

[0070] Next, the configuration of the flow path forming protrusion 58 of the second bracket 18 will be explained.

[0071] Figure 12 It is along Figure 3 A cross-sectional view of the second bracket portion of the EE line.

[0072] like Figure 3 , Figure 7 as well as Figure 12As shown, the flow path forming protrusion 58 integrally has a second end wall 58a extending radially from the open end of the peripheral wall 18a and having a predetermined circumferential width; a pair of second side walls 58b extending axially from one and the other end of the second end wall 58a to the bottom wall 18b, respectively, and erected radially and spaced apart circumferentially by a predetermined width; a second bottom wall 58c located between the pair of second side walls 58b and extending axially from the end of the second end wall 58a at the open end side to the bottom wall 18b; and a second bottom wall 58c located between the pair of second side walls 58b. A third partition wall 58d, located between the second side walls 58b and extending axially from the second end wall 58a to the bottom wall 18b and radially spaced from the second bottom wall 58c, is formed between the second side walls 58b and extends axially from the protruding end of the second end wall 58a to the bottom wall and radially spaced from the second partition wall 18b. A second top wall 58e, located between the second bottom wall 58c and the third partition wall 58d and connected to the second bottom wall 58c and the third partition wall 58d, is formed between the second bottom wall 58c and the third partition wall 58d. The flow path forming protrusion 58 has a third flow inlet IP3 formed on the second end wall 58a and opposite the other end of the first flow path F1, a fourth flow inlet IP4 formed on the second end wall 58a and located radially outside the third flow inlet IP3 and opposite the other end of the second flow path F2, and an exhaust port 60 formed on each of the second side walls 58b.

[0073] like Figure 7 As shown, the second flow path forming protrusion 58 also has a third flow outlet OP3 formed on the second bottom wall 58c and located adjacent to the bottom wall 18b, and a second flow port CP2 formed on the third partition wall 58d and opposite to the third flow outlet OP3. The aforementioned fourth partition wall 58f has one end connected to the second bottom wall 58c between the exhaust port 60 and the third flow outlet OP3, and the other end connected to the third partition wall 58d between the exhaust port 60 and the second flow port CP2, and defines a flow path connecting the second flow port CP2 and the third flow outlet OP3.

[0074] A second external gas flow path RA is formed by the second bottom wall 58c, the third partition wall 58d, a pair of second side walls 58b, and the fourth partition wall 58f, connecting the third inlet IP3 to the exhaust port 60. The second external gas flow path RA extends axially from the third inlet IP3 to the fourth partition wall 58f, between the second bottom wall 58c and the third partition wall 58d, and is connected to the exhaust port 60 formed on the pair of second side walls 58b.

[0075] A second internal gas flow path RI is formed by the third partition wall 58d, the second top wall 58e, the fourth partition wall 58f, and a pair of second side walls 58b, connecting the third outlet OP3 and the fourth inlet IP4. The second internal gas flow path RI extends axially from the fourth inlet IP4 to the vicinity of the bottom wall 18b, between the third partition wall 58d and the second top wall 58e, and further through the second flow port CP2 to the third outlet OP3. The circumferential widths of the second external gas flow path RA and the second internal gas flow path RI are formed to be approximately equal to the circumferential width of the flow path forming protrusion 58.

[0076] like Figure 3 As shown, with the second bracket 18 fixed to the second core pressing member 14b, the third inlet IP3 of each flow path forming protrusion 58 is opposite to the first flow port 44a of the second core pressing member 14b and the other end of the first flow path F1 of the stator 12. Thus, the second external gas flow path RA of the flow path forming protrusion 58 is connected to the other end of the first flow path F1 via the third inlet IP3 and the first flow port 44a. The fourth inlet IP4 of each flow path forming protrusion 58 is opposite to the second flow port 44b of the second core pressing member 14b and the other end of the second flow path F2 of the stator 12. Thus, the second internal gas flow path RI of the flow path forming protrusion 58 is connected to the other end of the second flow path F2 via the fourth inlet IP4 and the second flow port 44b. The third outlet OP3 of each flow path forming protrusion 58 opens into the outer space OA of the second bracket 18, and the second external gas flow path RA is connected to the outer space OA via the third outlet OP3.

[0077] The operation and cooling function of the rotary motor 10 configured as described above will be explained.

[0078] like Figure 3 As shown, when the rotary motor 10 is running, the stator coil 26 is energized and the rotor 28 rotates around the central axis C1. At this time, the stator coil 26 and the permanent magnet M generate heat, which is transferred to various parts within the rotary motor 10, causing the temperature to rise. The first fan FA and the second fan FB rotate together with the rotor 28's rotation shaft 30 around the central axis C1.

[0079] In addition, Figure 3In the diagram, solid arrows indicate the flow of external gas, and hollow arrows indicate the flow of internal gas. When the first fan FA rotates, airflow is generated in the outer space OA of the first bracket 16 through the outer blades 74. As a result, external gas is drawn into the outer space OA through the air inlet 55 located on the bottom wall 16b. The incoming external gas, i.e., cooling air, flows around the first bearing B1 and then radially along the fan body 70a and the bottom wall 16b within the outer space OA. A portion of this airflow flows into the first external gas flow path RA from the first inlet IP1 forming the protrusions 48 in each flow path. The cooling air flows through the first external gas flow path RA into the first flow path F1 of the stator 12, and after flowing through the first flow path F1, it flows into the second external gas flow path RA of the second bracket 18. After flowing through the second external gas flow path RA, the cooling air is discharged outside the machine from the exhaust port 60.

[0080] By introducing cooling air into the outer space OA through the air inlet 55 as described above, the first bearing B1 and the fan body 70a are cooled and their temperatures decrease. At this time, the heat from the rotor 28 and the inner space IA is transferred to the fan body 70a, and heat is dissipated from the fan body 70a to the cooling air. This helps to reduce the temperature of the rotor 28 and the inner space IA.

[0081] When cooling air flows through the first flow path F1 of the stator 12, it flows in direct contact with the outer peripheral surface of the stator core 24. Heat from the stator core 24 is dissipated to the cooling air, thus cooling the stator core 24. Because multiple first rectifier ribs 42b are provided in the first flow path F1, the cooling air flows approximately uniformly throughout the entire circumferential region without bias towards one side of the circumference. Simultaneously, by providing the first rectifier ribs 42b, the contact area between the stator core 24 and the cooling air is increased, which helps the stator core 24 dissipate heat and cool more efficiently.

[0082] Simultaneously, if the first fan FA rotates, an internal airflow is generated within the inner space IA of the first bracket 16 through the inner blades 73. The internal airflow flows out radially between the inner blades 73 and the inner cover 72 of the first fan FA. The outflowing internal gas passes around the coil end 27a and flows into the first internal gas flow path RI from the second inlet IP2 forming the flow path protrusion 48. After the inflowing internal gas flows through the first internal gas flow path RI, it flows into the second flow path F2 of the stator 12 and passes through the second flow path F2. Moreover, the internal gas passes through the second internal gas flow path RI of the second bracket 18 from the second flow path F2, flows into the inner space IA of the second bracket 18, and after flowing around the coil end 27b, it passes through the magnet insertion holes (inner peripheral gap 50a, outer peripheral gap 50b) 50 of the rotor core 32 and the gap (air gap) between the rotor core 32 and the stator core 24, returning to the inner space IA of the first bracket 16.

[0083] During the internal gas flow through the internal gas flow path RI of the first bracket 16, the internal gas is cooled by the external gas flowing through the first external gas flow path RA, separated by a partition wall, thus reducing its temperature. Furthermore, during the internal gas flow through the second flow path F2 of the stator 12, the internal gas is cooled by heat dissipation to the outside of the machine via the cover plate 20, thus reducing its temperature. Simultaneously, the internal gas is cooled by the cooling air flowing through the first flow path F1, separated by the main rib 42a, thus reducing its temperature. Because multiple second rectifying ribs 42c are provided in the second flow path F2, the internal gas flows approximately uniformly throughout the entire circumferential region without bias towards one side of the circumference. At the same time, by providing the second rectifying ribs 42c, the contact area of ​​the ribs on the stator core 24 side is increased, which helps to dissipate heat and cool the internal gas more efficiently. By circulating the cooled internal gas within the machine as described above, the heat from the stator coil 26, stator core 24, rotor core 32, and permanent magnet M can be dissipated to the internal gas, contributing to their cooling.

[0084] On the other hand, when the second fan FB rotates, an airflow is generated in the outer space OA of the second bracket 18 through the outer blades 78 and the outer casing 77. As a result, external gas is drawn into the outer space OA through the air inlet 65 provided in the bottom wall 18b. After flowing in, the external gas, i.e., the cooling air, flows around the second bearing B2 and along the outer surface of the fan body 76a, and then flows out of the machine from the exhaust port of the bottom wall 18b.

[0085] By introducing cooling air into the outer space OA, the second bearing B2 and the fan body 76a are cooled, thus reducing their temperature. At this time, heat from the rotor 28 and the inner space IA is transferred to the fan body 76a, and heat is dissipated from the fan body 76a to the cooling air. This helps to reduce the temperature of the rotor 28 and the inner space IA.

[0086] The rotary electric motor of this embodiment, configured as described above, has a first flow path F1 that is in contact with the outer peripheral surface of the stator core 24, and a second flow path that covers the radial outer peripheral side of the first flow path F1. By employing a configuration in which external gas flows in the first flow path F1 and internal gas flows in the second flow path F2, the stator core 24 can be efficiently cooled by the external gas, and the heat of the internal gas flowing through the second flow path F2 can be dissipated to the outside of the machine, thus cooling the internal gas by the external gas. By circulating the cooled internal gas within the rotary electric motor, it is beneficial to cool the stator coils, rotor core, permanent magnets, and other components inside the machine.

[0087] The first flow path F1 of the stator 12 is formed by a flow path forming part 40 that includes a rib 42 integrally formed with the electromagnetic steel plate P1 constituting the stator core 24. Therefore, it is not necessary to provide a separate ventilation duct on the outer periphery of the stator, which can reduce the number of parts and miniaturize the rotary motor.

[0088] Furthermore, the first bracket 16 has multiple flow path forming protrusions 48, within which are formed external gas flow paths RA communicating with the first flow path F1 of the stator 12 and internal gas flow paths RI communicating with the second flow path F2 of the stator 12. That is, the first bracket 16 is integrally constructed with multiple external gas flow paths RA and multiple internal gas flow paths RI. Similarly, the second bracket 18 is integrally constructed with multiple external gas flow paths RA and multiple internal gas flow paths RI. Therefore, it is unnecessary to provide separate ventilation ducts for the first and second brackets, enabling a reduction in the number of components and miniaturization of the rotary motor.

[0089] Based on the above description, according to this embodiment, a fully enclosed rotary motor with improved cooling capacity and miniaturization can be provided.

[0090] While embodiments of the invention have been described, they are presented as examples and are not intended to limit the scope of the invention. The novel embodiments described above can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments are included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

[0091] For example, in the above embodiment, the flow path forming portions of the stator are provided at four locations on the outer periphery of the stator core, but this is not a limitation; the flow path forming portions may also be provided in two, three, or five or more configurations. The number of flow path forming protrusions on the first and second brackets can be increased or decreased depending on the number of flow path forming portions. The rotary motor of the present invention is not limited to permanent magnet type rotary motors, but can also be applied to induction rotary motors with cage-type rotors.

Claims

1. A rotary electric motor, characterized in that, have: A stator includes a cylindrical stator core having a first end face at one end in the axial direction and a second end face at the other end in the axial direction, and an outer peripheral surface; a stator coil mounted on the stator core; and a first flow path forming portion provided on the outer periphery of the stator core. The first flow path forming portion forms a first flow path extending from one end in the axial direction of the stator core to the other end, and a second flow path located outside the first flow path in the radial direction of the stator core and extending from one end in the axial direction of the stator core to the other end. The first bracket has an annular peripheral wall having an open end facing the first end face, a bottom wall facing the first end face at a distance, and a second flow path forming portion formed by a part of the peripheral wall. as well as The second bracket has an annular peripheral wall with an open end facing the second end face, and a bottom wall that is spaced apart from the second end face. The second flow path forming part of the first bracket includes: The first end wall extends radially from the open end of the peripheral wall and has a circumferential width; A pair of first sidewalls, extending axially from one end and the other end of the first endwall in the circumferential direction to the bottom wall, and erected radially and spaced apart from each other in the circumferential direction; A first bottom wall, located between the pair of first side walls, extends axially from the end of the first end wall at the open end side to the bottom wall and has the first circumferential width; A first partition wall, located between the pair of first sidewalls, extends from the first endwall along the axial direction to the bottom wall and has the first circumferential width, and is radially spaced apart from the first bottom wall; A first top wall, located between the pair of first side walls, extends axially from the end of the protruding side of the first end wall to the bottom wall and has the first circumferential width, and is radially spaced apart from the first partition wall; A first flow outlet is formed on the first end wall and has a predetermined circumferential width, and is opposite to one end of the first flow path; A second flow outlet is formed on the first end wall and has a predetermined width in the circumferential direction, located on the outer side of the radial direction relative to the first flow outlet and opposite one end of the second flow path; A first inlet is formed on the first bottom wall and located adjacent to the bottom wall, having the first width in the circumferential direction; The second inlet is formed on the first bottom wall and located on the side of the first end wall relative to the first inlet, and has a second circumferential width smaller than the first width; A flow opening, formed in the first partition wall and located opposite the second flow inlet, has a third circumferential width smaller than the first width; as well as A cylindrical second partition wall, located between the first bottom wall and the first partition wall, has one end connected to the first bottom wall and located around the second inlet, and another end connected to the first partition wall and located around the flow outlet. An external gas flow path connecting the first inlet and the first outlet is formed by the first bottom wall, the first partition wall, the pair of first side walls, and the second partition wall. An internal gas flow path connecting the second inlet and the second outlet is formed by the first partition wall, the first top wall, the pair of first side walls, and the second partition wall.

2. The rotary motor as described in claim 1, characterized in that, The second bracket has a third flow path forming portion formed by a part of the peripheral wall. The third flow path forming unit includes: The second end wall extends radially from the opening end of the peripheral wall and has a predetermined width in the circumferential direction; A third flow inlet is formed on the second end wall and is opposite to the other end of the first flow path; A fourth flow inlet is formed on the second end wall, located radially outside the third flow inlet, and opposite the other end of the second flow path; A pair of second sidewalls extend axially from one end and the other end of the first endwall in the circumferential direction to the bottom wall, and are erected radially and opposed to each other in the circumferential direction across the first width; An exhaust port is formed on the second sidewall; The second bottom wall is located between the pair of second side walls and extends axially from the end of the second end wall at the open end side to the bottom wall; A third partition wall, located between the pair of second side walls, extends from the second end wall along the axial direction to the bottom wall and is radially opposed to the second bottom wall by a gap; The second top wall, located between the pair of second side walls, extends axially from the protruding end of the second end wall to the bottom wall and is radially opposed to the second partition wall by a gap; A third outlet is formed in the second bottom wall and located adjacent to the bottom wall; A second flow port is formed in the third partition wall and is opposite to the third flow inlet; as well as The fourth partition wall, located between the second bottom wall and the second partition wall, has one end connected to the second bottom wall between the exhaust port and the third outlet, and another end connected to the third partition wall between the exhaust port and the second flow port. An external gas flow path connecting the third inlet and the exhaust port is formed by the second bottom wall, the third partition wall, the pair of second side walls, and the fourth partition wall. An internal gas flow path connecting the fourth inlet and the third outlet is formed by the third partition wall, the fourth partition wall, the second top wall, and the pair of second side walls.

3. The rotary motor as described in claim 2, characterized in that, It also has: A first bearing is disposed on the bottom wall of the first bracket; The second bearing is disposed on the bottom wall of the second bracket; The rotor has a rotating shaft that is rotatably supported by the first bearing and the second bearing about a central axis and is coaxially arranged with the stator, and a rotor core that is mounted on the rotating shaft and coaxially arranged inside the stator core. A first fan is mounted on the rotating shaft between the first bearing and the rotor core, and rotates freely integrally with the rotating shaft; and The second fan is mounted on the rotating shaft between the second bearing and the rotor core, and rotates freely integrally with the rotating shaft. The first fan has a fan body, multiple outer blades, and multiple inner blades. The fan body is fixed to the rotating shaft, dividing the internal space of the first bracket into an outer space located between the bottom wall and the first fan and communicating with the first flow inlet and the air inlet located on the bottom wall, and an inner space located between the stator core and the rotor core and the first fan and communicating with the second flow inlet. The multiple outer blades are located on the outer surface of the fan body and in the outer space, and the multiple inner blades are located on the inner surface of the fan body and in the inner space.

4. The rotary motor as described in claim 3, characterized in that, The second fan has a fan body and multiple outer blades. The fan body is fixed to the rotating shaft and divides the internal space of the second bracket into an outer space located between the bottom wall and the second fan and communicating with the air inlet located on the bottom wall, and an inner space located between the stator core and the rotor core and the second fan and communicating with the third outlet. The multiple outer blades are located on the outer surface of the fan body and in the outer space.

5. The rotary motor as described in claim 1, characterized in that, The stator core is a stacked core formed by stacking multiple magnetic steel plates concentrically. The first flow path forming part has ribs integrally formed on the outer periphery of each magnetic steel plate. The ribs include main ribs that extend radially outward from the outer periphery of the magnetic steel plate and define the first flow path between the main ribs and the outer periphery, multiple first rectifying ribs that extend between the main ribs and the outer periphery and are circumferentially separated from each other, and multiple second rectifying ribs that extend radially outward from the outer edge of the main ribs.

6. The rotary electric motor as described in claim 5, characterized in that, The first rectifier rib is located within the first flow path, forming a rectifier plate that extends axially from one end of the stator core to the other end.

7. The rotary electric motor as described in claim 6, characterized in that, The first flow path forming part has a cover plate fixed to the outer peripheral surface of the stator core and covering the rib. The second flow path is defined between the outer edge of the main rib and the inner surface of the cover plate. The second rectifier rib is located in the second flow path, forming a rectifier plate extending from one end of the stator core to the other end in the axial direction.

Images