JP2017099147A - Motor and electrically-driven supercharger with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor which supplies a fluid to a fluid bearing in a simple fluid supply structure and is capable of cooling a stator by utilizing the fluid.SOLUTION: A motor 1 comprises a housing 8, a stator 9 and a rotor 10. In the housing, first and second fluid bearings 11 and 12 which support a rotary shaft 10a of the rotor in a rotatable manner are provided. The housing includes a first holding part 23 and a second holding part 24 and in the housing, a first supply flow passage 31 of which one end side is opened outside of the housing and the other end side is connected to the first fluid bearing, a branch flow passage 32 which is branched from the first supply flow passage and of which one end side is opened at a holding surface side of the first holding part, and a second supply flow passage 44 of which one end side is opened at a holding surface side of the second holding part and the other end side is connected to the second fluid bearing are formed. Further, in the stator, a penetrating flow passage 50 which penetrates in an axial direction in such a manner that the one end side of the branch flow passage and the one end side of the second supply flow passage are connected is formed, and the penetrating flow passage cools the stator with a fluid flowing within the penetrating flow passage.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor and an electric supercharger including the motor, and more specifically, a motor provided with a first fluid bearing and a second fluid bearing that rotatably support a rotating shaft of a rotor in a housing, and the motor. The present invention relates to an electric supercharger.

  As a conventional motor, a motor including a housing, a cylindrical stator attached in the housing, and a rotor provided on the inner peripheral side of the stator is generally known. In this motor, when a fluid bearing is employed as a bearing for the rotor rotation shaft, a configuration in which the fluid bearing is disposed on one side (so-called cantilever configuration) and a configuration in which the fluid bearing is disposed on both sides with respect to the rotor rotation shaft (so-called so-called configuration) , Both-sided form). This one-sided configuration of the hydrodynamic bearing has poor durability against vibrations during rotor rotation, external vibrations, or impacts. In addition, extremely high-precision processing and assembly are required to suppress the vibration of the rotor itself. On the other hand, the both-side arrangement form of the fluid bearing is excellent in durability against vibration or impact, but it is necessary to provide an individual flow path for each fluid bearing and to connect an individual fluid supply source to each flow path. It becomes a complicated fluid supply structure, and the number of parts increases.

  Thus, motors having a simple fluid supply structure have been proposed as motors in which fluid bearings are arranged on both sides (see, for example, Patent Documents 1 and 2). In Patent Document 1, for example, as shown in FIG. 6, an oil supply pipe 113 connected to each fluid bearing 111, 112 is provided in a housing 108, and a hydraulic pump 114 is connected to one end side of the oil supply pipe 113. A motor 107 that supplies oil to the fluid bearings 111 and 112 through an oil supply pipe 113 is disclosed. In the motor 107, a cooling jacket 119 for cooling the stator 109 is provided outside the housing 108. Further, in Patent Document 2, for example, as shown in FIG. 7, a first supply flow path 213 a connected to one fluid bearing 211 and a second supply connected to the other fluid bearing 212 are connected to a housing 208. The first and second supply channels 213a and 213b are connected to the oil pump 214, and oil is supplied to the fluid bearings 211 and 212 through the first and second supply channels 213a and 213b. A motor 207 is disclosed. In the motor 207, a cooling water passage 219 for cooling the stator 209 is formed in the housing 208.

JP-A-9-46974 JP 2008-115731 A

  However, in the technique disclosed in Patent Document 1, the oil supply pipe 113 is inserted into the slot of the stator 109 together with the coil (see paragraph [0017]) and is not intended to cool the stator 109. For this reason, a cooling jacket 119 is separately provided on the outside of the housing 108, which increases cost and physique. In the technique disclosed in Patent Document 2, the first and second supply channels 213a and 213b are not intended to cool the stator 209, and therefore a cooling water passage 219 is separately formed in the housing 208. The cost and physique will increase.

  The present invention has been made in view of the above situation, and can supply fluid with a simple fluid supply structure to the first fluid bearing and the second fluid bearing that pivotally support the rotating shaft of the rotor. An object of the present invention is to provide a motor that can cool a stator by using the motor and an electric supercharger including the motor.

In order to solve the above problem, an invention according to claim 1 includes a housing, a cylindrical stator attached in the housing, and a rotor provided on an inner peripheral side of the stator, and the housing includes Is a motor provided with a first fluid bearing and a second fluid bearing that rotatably support the rotating shaft of the rotor, wherein the housing is between the first sandwiching portion and the first sandwiching portion. And a second holding portion for holding the stator in the axial direction, wherein the housing has a first supply channel in which one end side opens to the outside of the housing and the other end side is connected to the first fluid bearing. A branch channel that branches from the first supply channel and has one end opened to the clamping surface of the first clamping unit, one end opened to the clamping surface of the second clamping unit, and the other end Second supply connected to the second fluid bearing A flow passage is formed, and the stator is formed with a through flow passage penetrating in the axial direction so as to connect one end side of the branch flow passage and one end side of the second supply flow passage. In addition, the gist of the through-flow passage is configured to cool the stator with a fluid flowing through the passage.
According to a second aspect of the present invention, in the first aspect of the present invention, the through passage is formed along the axial direction of the stator, and a plurality of through passages are formed in the circumferential direction of the stator. A first annular channel that communicates between one end side of the branch channel and one end side of the plurality of through channels between the clamping surface of the first clamping part and one shaft end surface of the stator. Between the clamping surface of the second clamping part and the other shaft end surface of the stator, one end side of the second supply channel and each other side of the plurality of through channels. The gist is that a second annular flow path is formed.
According to a third aspect of the present invention, in the second aspect of the present invention, the first annular flow path blocks the first annular groove and the first annular groove formed on the sandwiching surface of the first sandwiching portion. The second annular channel is formed by a shaft end surface of the stator, and the second annular channel is formed on the clamping surface of the second clamping part, and the other of the stator that blocks the second annular groove. The gist of the present invention is that it is formed by the shaft end face.
According to a fourth aspect of the present invention, in the invention according to the second or third aspect, the stator includes a cylindrical stator core provided with a plurality of winding portions protruding in the circumferential direction, and a plurality of winding portions protruding in an inner circumferential side. A coil wound around each of the winding portions, and each of the plurality of through flow paths is disposed on the centrifugal side of the winding portion in the radial direction of the stator core.
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the stator has a cylindrical shape in which a plurality of winding portions projecting toward the inner peripheral side are provided in the circumferential direction. A stator core, a coil wound around each of the plurality of winding portions, and a resin mold portion provided between the winding portions adjacent to each other in the circumferential direction so as to cover the coils, and the resin mold The gist is that the portion is in close contact with the inner surface of the housing.
In order to solve the above problem, an invention described in claim 6 is an electric supercharger for supplying compressed air to an internal combustion engine, and the motor according to any one of claims 1 to 5. And a compressor having an impeller attached to one end of the rotating shaft of the rotor.

According to the motor of the present invention, the housing includes the first clamping portion and the second clamping portion that clamps the stator in the axial direction between the first clamping portion, and one end side of the housing is located outside the housing. A first supply channel that opens and has the other end connected to the first fluid bearing; a branch channel that branches from the first supply channel and that opens at one end side to the clamping surface of the first clamping unit; and one end side A second supply channel is formed that opens to the clamping surface side of the second clamping part and has the other end connected to the second fluid bearing. The stator is formed with a through channel that penetrates in the axial direction so as to connect one end side of the branch channel and one end side of the second supply channel, and the through channel flows through the inside. The stator is configured to be cooled with a fluid. Thereby, the fluid flowing from the opening into the first supply channel by the fluid supply source is supplied to the first fluid bearing through the first supply channel, and the branch channel, the through channel, and the second channel. It is supplied to the second fluid bearing through the supply channel. Then, the stator is cooled by an endothermic action when the fluid flows through the through flow path. Therefore, the fluid can be supplied to the first fluid bearing and the second fluid bearing that support the rotating shaft of the rotor with a simple fluid supply structure, and the stator can be cooled using the fluid. In particular, it is not necessary to separately provide a complicated stator cooling structure as in the prior art, which leads to cost reduction and physique reduction. Furthermore, since the viscosity of the fluid itself flowing through the through flow path is lowered by heat absorption, the resistance due to the fluid viscosity in the second fluid bearing is reduced, which can contribute to higher efficiency.
In addition, the through channel is formed along the axial direction of the stator, and a plurality of the through channels are formed in the circumferential direction of the stator, and the clamping surface of the first clamping part and one axis of the stator A first annular channel is formed between the end surface and the second annular channel is formed between the clamping surface of the second clamping unit and the other shaft end surface of the stator; The fluid flowing through the flow path spreads in a ring shape in the first annular flow path, passes through each through flow path, and is then aggregated in the second annular flow path to flow through the second supply flow path. And a stator is cooled over the circumferential direction by the heat absorption effect | action at the time of a fluid flowing through several through flow paths.
The first annular flow path is formed by a first annular groove formed on a sandwiching surface of the first sandwiching portion and one shaft end surface of the stator that closes the first annular groove, When the two annular channels are formed by the second annular groove formed on the clamping surface of the second clamping part and the other shaft end surface of the stator closing the second annular groove, the annular channel is annular on the stator side. Compared with the one forming the flow path, a large magnetic path area can be secured and the motor output can be improved.
Further, when the stator includes a stator core and a coil, and each of the plurality of through passages is disposed on the centrifugal side of the winding portion in the radial direction of the stator core, It is possible to effectively cool a portion where heat generation is easily transmitted.
Further, when the stator includes a stator core, a coil, and a resin mold portion, and the resin mold portion is in close contact with the inner surface of the housing, heat generation of the coil is easily transmitted to the stator and the housing. It is easy to be done.
According to the electric supercharger of the present invention, the above-described motor and a compressor having an impeller attached to one end side of the rotating shaft of the rotor are provided. As a result, compressed air generated by the impeller rotating at high speed is supplied to the internal combustion engine.

The present invention will be further described in the following detailed description with reference to the drawings referred to, with reference to non-limiting examples of exemplary embodiments according to the present invention. Similar parts are shown throughout the several figures.
It is a longitudinal section of an electric supercharger provided with a motor concerning an example. It is the II-II sectional view taken on the line of FIG. It is a principal part enlarged view of FIG. It is a perspective view of the stator core which concerns on an Example. It is explanatory drawing of the annular flow path of another form. It is a longitudinal cross-sectional view of the conventional motor. It is a longitudinal cross-sectional view of another conventional motor.

  The items shown here are exemplary and illustrative of the embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

<Motor>
The motor according to the present embodiment includes a housing (8), a cylindrical stator (9) mounted in the housing, and a rotor (10) provided on the inner peripheral side of the stator. This is a motor (7) provided with a first fluid bearing (11) and a second fluid bearing (12) that rotatably support the rotation shaft (10a) (see, for example, FIGS. 1 and 2). The housing (8) includes a first clamping part (23) and a second clamping part (24) that clamps the stator (9) in the axial direction between the first clamping part and the housing (8 ), A first supply channel (31) whose one end side opens to the outside of the housing and the other end side is connected to the first fluid bearing (11), and one end side is branched from the first supply channel. The branch flow path (32) opened to the clamping surface (23a) side of the clamping part (23), one end side opened to the clamping surface (24a) side of the second clamping part (24), and the other end side was the second fluid bearing. And a second supply channel (44) connected to (12). Further, the stator (9) is formed with a through channel (50) penetrating in the axial direction so as to connect one end side of the branch channel (32) and one end side of the second supply channel (44). The through-flow path is configured to cool the stator (9) with a fluid flowing through the through-flow path.

  As the motor according to the present embodiment, for example, the through channel (50) is formed along the axial direction of the stator (9), and a plurality of the through flow paths (50) are formed in the circumferential direction of the stator. Between the clamping surface (23a) of the clamping part (23) and one shaft end surface (9a) of the stator (9), each of the one end side of the branch channel (32) and the plurality of through channels (50) is provided. A first annular channel (51) that communicates with one end side is formed, and is between the clamping surface (24a) of the second clamping part (24) and the other shaft end surface (9b) of the stator (9). Is formed with a second annular channel (52) that connects one end side of the second supply channel (44) and the other end side of the plurality of through channels (50) (for example, FIG. 1). And FIG. 2).

  In the case of the above-described embodiment, for example, the first annular channel (51) closes the first annular groove (53) and the first annular groove formed in the clamping surface (23a) of the first clamping part (23). The second annular channel (52) is formed on the clamping surface (24a) of the second clamping part (24), and is formed by one shaft end surface (9a) of the stator (9). (54) and the other shaft end surface (9b) of the stator (9) that closes the second annular groove (see, for example, FIG. 3).

  In the case of the above-mentioned form, for example, the stator (9) includes a cylindrical stator core (15) provided with a plurality of winding portions (15a) protruding in the circumferential direction and a plurality of windings. A coil (16) wound around each of the portions, and each of the plurality of through flow paths (50) is disposed on the centrifugal side of the winding portion (15a) in the radial direction of the stator core (15). (See, for example, FIG. 2).

  As the motor according to the present embodiment, for example, the stator (9) includes a cylindrical stator core (15) provided with a plurality of winding portions (15a) protruding in the circumferential direction and a plurality of winding portions (15a) protruding in the circumferential direction. A coil (16) wound around each of the winding parts, and a resin mold part (17) provided between the winding parts adjacent to each other in the circumferential direction so as to cover the coil, The form (for example, refer FIG.1 and FIG.2 etc.) closely_contact | adhered to the inner surface of a housing (8) can be mentioned.

  As the motor according to the present embodiment, the housing (8) includes a cylindrical first case (21) capable of accommodating the stator (9), and a second case (22) joined to the first case in the axial direction. The first case (21) is provided with a first clamping part (23), a first fluid bearing (11), a first supply channel (31), and a branch channel (32). The second case (22) is provided with a second clamping part (24), a second fluid bearing (12), and a second supply channel (44) (see, for example, FIG. 1). Can be mentioned. Thereby, each flow path etc. can be formed easily and it can be set as a simple and cheap structure as a whole.

<Electric supercharger>
The electric supercharger according to the present embodiment is an electric supercharger (1) for supplying compressed air to an internal combustion engine, and includes a motor (7) according to the above embodiment and a rotating shaft of the rotor (10). A compressor (3) having an impeller (2) attached to one end of (10a) (see, for example, FIG. 1).

  In addition, the code | symbol in the parenthesis of each structure described in the said embodiment shows the correspondence with the specific structure as described in the Example mentioned later.

  Hereinafter, the present invention will be specifically described with reference to the drawings. In the present embodiment, as the “motor” according to the present invention, a motor provided in an electric supercharger (also referred to as “electric turbocharger”) incorporated in the intake passage of the internal combustion engine is exemplified.

  As shown in FIG. 1, the electric supercharger 1 includes a motor 7 which will be described later, and a compressor 3 having an impeller 2 attached to one end of a rotating shaft 10 a of a rotor 10 constituting the motor 7. . The compressor 3 includes a housing 4 that houses the impeller 2 and generates compressed air by the rotation of the impeller 2. The housing 4 is joined to a housing 8 described later (specifically, a second case 22 described later) by appropriate joining means (for example, a clamp, bolting, screwing, etc.).

(1) Configuration of Motor As shown in FIGS. 1 and 2, the motor 7 according to the present embodiment is provided on a housing 8, a cylindrical stator 9 attached in the housing 8, and an inner peripheral side of the stator 9. And a rotor 10 to be provided. The housing 8 is provided with a first fluid bearing 11 and a second fluid bearing 12 that rotatably support the rotating shaft 10 a of the rotor 10. The first and second fluid bearings 11 and 12 are fluid bearings ("semi-float bearings") that support the rotating shaft 10a by supplying oil from the supply holes 11a and 12a to the inner periphery thereof to form an oil film. Also called).

  The stator 9 is a cylindrical stator core 15 in which a plurality of teeth 15 a (exemplified as “winding portions” according to the present invention) projecting toward the inner peripheral side are provided in the circumferential direction (six in FIG. 2). And a coil 16 wound around each of the plurality of teeth 15a, and a resin mold portion 17 filled between the teeth 15a adjacent in the circumferential direction so as to cover the coil 16.

  The stator core 15 is formed of a laminated steel plate that is laminated in the axial direction. The coil 16 is formed by winding a wire around the tooth 15 a via the insulator 18. Further, the resin mold portion 17 is in close contact with the inner surface of the housing 8 (specifically, the surface of a housing recess 29 of the first case 21 described later). Further, the rotor 10 includes a permanent magnet 19 disposed on the outer peripheral side of the rotating shaft 10a. On the outer peripheral side of the permanent magnet 19, a holding cylinder 20 made of resin (for example, CFRP) for holding the permanent magnet 19 is provided. In the motor 7, an electromagnetic force is generated by supplying a current to the coil 16, and torque is applied to the rotor 10 by the electromagnetic force and the magnetic force of the permanent magnet 19 in the rotor 10.

  The housing 8 includes a first case 21 made of metal, and a second case 22 made of metal that is joined to the first case 21 in the axial direction by appropriate joining means (for example, a clamp, bolting, screwing, etc.) It is equipped with. The first case 21 includes an annular first clamping part 23, and the second case 22 is an annular second clamping part that clamps the stator 9 in the axial direction between the first case 21 and the second case 22. 24.

  The first case 21 includes a bottom portion 26a and a cylindrical portion 26b that rises from the bottom portion 26a. On the center side of the bottom portion 26a, an insertion hole 27 through which the rotary shaft 10a is inserted and the first fluid bearing 11 is provided is formed. A sealing member 28 provided on the outer peripheral side of the rotary shaft 20a is in pressure contact with the insertion hole 27. An accommodation recess 29 for accommodating the resin mold portion 17 is formed on the surface side of the bottom portion 26a where the cylindrical portion 26b rises. In addition, a first clamping portion 23 is provided on the outer peripheral side of the housing recess 29 of the bottom portion 26a.

  The bottom portion 26 a of the first case 21 includes a first supply channel 31 having one end opened to the outside of the first case 21 and the other end connected to the first fluid bearing 11, and the first supply channel 31. A branch flow path 32 is formed that branches and opens at one end side toward the clamping surface 23 a of the first clamping part 23. The first supply channel 31 extends in the radial direction of the first case 21. Further, the branch flow path 32 extends in the axial direction of the first case 21. Further, the bottom portion 26a has a first discharge flow path 33 having one end opened to the outside of the first case 21 and the other end connected to one end of the first fluid bearing 11 of the insertion hole 27, and a first discharge flow. A branch flow path 34 that branches from the path 33 and that has one end connected to the other end of the first fluid bearing 11 of the insertion hole 27 is formed. The first discharge channel 33 extends in the radial direction of the first case 21. Further, the branch flow path 34 is inclined and extends in the axial direction of the first case 21.

  The second case 22 includes a bottom portion 37a and a cylindrical portion 37b that rises from the bottom portion 37a. An insertion hole 38 through which the rotary shaft 10a is inserted and the second fluid bearing 12 is provided is formed on the center side of the bottom portion 37a. A seal member 39 provided on the outer peripheral side of the rotary shaft 10a is in pressure contact with the insertion hole 38. Further, a flange-shaped second clamping portion 24 is provided on the distal end side of the cylindrical portion 37b. An annular seal member 40 is provided between the clamping surface 24 a of the second clamping part 24 and the shaft end surface 9 b of the stator 9 so as to surround a plurality of through passages 50 described later. The seal member 40 is mounted in a mounting groove 41 formed on the clamping surface 24a of the second clamping part 24 (see FIG. 3). Further, an annular seal member 42 is provided between the inner peripheral surface of the cylindrical portion 37 b and the outer peripheral surface of the resin mold portion 17.

  A second supply channel 44 is formed in the bottom portion 37a of the second case 22 so that one end side opens to the clamping surface 24a side of the second clamping unit 24 and the other end side is connected to the second fluid bearing 12. . The second supply channel 44 includes a portion extending in the radial direction of the second case 22 and a portion extending in the axial direction of the first case 22 from the distal end side of this portion. The bottom 37a has a second discharge passage 45 having one end opened to the outside of the second case 22 and the other end connected to one end of the second fluid bearing 12 of the insertion hole 38, and a second discharge flow. A branch flow path 46 branched from the path 45 and having one end connected to the other end of the second fluid bearing 12 of the insertion hole 38 is formed. The second discharge channel 45 extends in the radial direction of the second case 22. Further, the branch flow path 46 extends while inclining in the axial direction of the second case 22.

  Note that the opening sides of the first supply flow path 31, the first discharge flow path 33, and the second discharge flow path 45 are connected to an oil circulation path 47. The oil is supplied from the opening 31 a into the first supply flow path 31 by the oil pump 48 provided in the oil circulation path 47, while being discharged from the first discharge flow path 33 and the second discharge flow path 45. Is cooled by an oil cooler 49 provided in the oil circulation path 47.

  The stator 9 is formed with a through flow passage 50 penetrating in the axial direction so as to connect one end side of the branch flow passage 32 and one end side of the second supply flow passage 44 (see FIG. 4). The through channel 50 is configured to cool the stator 9 with oil flowing through the through channel 50. Specifically, the through-flow passage 50 is formed along the axial direction of the stator 9, and a plurality of (in FIG. 2) at regular angular intervals (60-degree intervals in FIG. 2) in the circumferential direction of the stator 9. 6) formed. Each of the plurality of through channels 50 is arranged on the distal side of the teeth 15 a in the radial direction of the stator core 15.

  Between the clamping surface 23a of the said 1st clamping part 23 and one axial end surface 9a of the stator 9, the 1st cyclic | annular form which connects the one end side of the branch flow path 32, and each one end side of the some through-flow path 50 is connected. A flow path 51 is formed. The first annular channel 51 is formed by a first annular groove 53 formed on the clamping surface 23 a of the first clamping part 23 and one shaft end surface 9 a of the stator 9 that closes the first annular groove 53 ( (See FIG. 3). Further, the first annular flow channel 51 is formed in an annular shape centering on the axis of the rotation shaft 10 a of the rotor 10. Furthermore, one end side of the branch flow path 32 is connected to an intermediate side of a position where one end side of the through flow path 50 adjacent to the first annular flow path 51 in the circumferential direction is connected (see FIG. 4). .

  Between the clamping surface 24 a of the second clamping part 24 and the other shaft end surface 9 b of the stator 9, one end side of the second supply channel 44 and each other side of the plurality of through channels 50 are communicated. A second annular channel 52 is formed. The second annular channel 52 is formed by a second annular groove 54 formed on the clamping surface 24a of the second clamping part 24 and the other shaft end surface 9b of the stator 9 that closes the second annular groove 54 ( (See FIG. 3). The second annular flow path 52 is formed in an annular shape centered on the axis of the rotation shaft 10 a of the rotor 10. Furthermore, one end side of the second supply channel 44 is connected to an intermediate side of the position where the other end side of the through channel 50 adjacent to the second annular channel 52 in the circumferential direction is connected (see FIG. 4).

  In this embodiment, the first case 21 is used as a part of the mold, and a resin mold is placed in the housing recess 29 of the first case 21 by pouring the resin into the first case 21 and evacuating it. The part 17 shall be formed in close contact.

(2) Operation of Electric Supercharger Next, the operation of the electric supercharger 1 having the above configuration will be described. By driving the motor 7, the impeller 2 of the compressor 3 is rotated at a high speed to generate compressed air in the housing 4, and the compressed air is supplied to the internal combustion engine. When the motor 7 is driven, oil flows into the first supply flow path 31 from the opening 31 a by the oil pump 48. The inflowing oil is supplied to the first fluid bearing 11 through the first supply flow path 31 and through the branch flow path 32 in the first annular flow path 51 as indicated by the broken line arrow in FIG. After expanding in an annular shape and passing through each through-flow channel 50, they are aggregated in the second annular channel 52 and supplied to the second fluid bearing 12 through the second supply channel 44. The oil supplied to the first fluid bearing 11 is returned to the oil circulation passage 47 through the first discharge passage 33 and the branch passage 34, and the oil supplied to the second fluid bearing 12 is second The oil is returned to the oil circulation path 47 through the discharge flow path 45 and the branch flow path 46.

  Here, the stator 9 is cooled in the circumferential direction by an endothermic action when oil flows through the plurality of through passages 50. Specifically, the heat generated by the coil 16 is received by the stator 9 after being received by the resin mold portion 17, and is removed by the endothermic action of oil flowing through each through passage 50, and the housing 4 (particularly, the first case). 21) heat is received and released.

(3) Effects of Example According to the motor 7 of this example, the housing 8 includes the first clamping unit 23 and the second clamping unit 24 that clamps the stator 9 in the axial direction between the first clamping unit 23 and the first clamping unit 23. The housing 8 has a first supply flow path 31 having one end opened to the outside of the housing 8 and the other end connected to the first fluid bearing 11, and one end branched from the first supply flow path 31. A branch channel 32 having a side opened to the clamping surface 23a side of the first clamping unit 23, a second channel having one end opened to the clamping surface 24a side of the second clamping unit 24 and the other end connected to the second fluid bearing 12. A supply flow path 44 is formed. The stator 9 is formed with a through channel 50 penetrating in the axial direction so as to connect one end side of the branch channel 32 and one end side of the second supply channel 44. The stator 9 is cooled by oil flowing through the inside. As a result, oil that flows from the opening 31a into the first supply flow path 31 by the oil pump 48 is supplied to the first fluid bearing 11 through the first supply flow path 31, and the branch flow path 32, through The fluid is supplied to the second fluid bearing 12 through the channel 50 and the second supply channel 44. Then, the stator 9 is cooled by an endothermic action when the oil flows through the through passage 50. Therefore, oil can be supplied to the first fluid bearing 11 and the second fluid bearing 12 that support the rotating shaft 10a of the rotor 10 with a simple fluid supply structure, and the stator 9 is cooled using the oil. Can do. In particular, it is not necessary to separately provide a complicated stator cooling structure as in the prior art, which leads to cost reduction and physique reduction. Furthermore, since the viscosity of the oil itself flowing through the through passage 50 is lowered by heat absorption, the resistance due to the oil viscosity in the second fluid bearing 12 is reduced, which can contribute to higher efficiency.

  In the present embodiment, the through flow path 50 is formed along the axial direction of the stator 9 and is formed in a plurality in the circumferential direction of the stator 9. A first annular channel 51 is formed between one shaft end surface 9 a of the stator 9, and a second annular channel 51 is formed between the clamping surface 24 a of the second clamping portion 24 and the other shaft end surface 9 b of the stator 9. An annular channel 52 is formed. As a result, the oil flowing through the branch flow path 32 spreads in a ring shape in the first annular flow path 51, passes through each through flow path 50, and then aggregates in the second annular flow path 52 to flow through the second supply flow path 44. . Then, the stator 9 is cooled in the circumferential direction by an endothermic action when the oil flows through the plurality of through passages 50.

  In the present embodiment, the first annular channel 51 includes a first annular groove 53 formed on the clamping surface 23 a of the first clamping part 23, and one shaft end surface 9 a of the stator 9 that closes the first annular groove 53. The second annular channel 52 is formed by a second annular groove 54 formed on the clamping surface 24a of the second clamping part 24 and the other shaft end surface 9b of the stator 9 that closes the second annular groove 54. Is formed. Thereby, compared with what forms an annular flow path in the stator side, a magnetic path area can be ensured large and a motor output can be improved.

  In the present embodiment, the stator 9 includes a stator core 15 and a coil 16, and each of the plurality of through passages 50 is disposed on the centrifugal side of the teeth 15 a in the radial direction of the stator core 15. Thereby, the part in which the heat of the coil 16 is easily transmitted in the stator 9 can be effectively cooled.

  In the present embodiment, the stator 9 includes a stator core 15, a coil 16, and a resin mold part 17, and the resin mold part 17 is in close contact with the inner surface of the housing 8. Thereby, the heat generated by the coil 16 is easily transmitted to the stator 9 and the housing 8 and is easily removed.

  Further, in the present embodiment, the housing 8 includes a cylindrical first case 21 that can accommodate the stator 9, and a second case 22 that is joined to the first case 21 in the axial direction. Are provided with a first clamping part 23, a first fluid bearing 11, a first supply channel 31 and a branch channel 32, and the second case 22 has a second clamping unit 24, a second fluid bearing 12. And the 2nd supply flow path 44 is provided. Thereby, each flow path 31, 32, 44 etc. can be formed easily, and it can be set as a simple and cheap structure as a whole. In particular, by using the first case 21 as a part of the mold, the resin mold portion 17 can be easily adhered to the inner surface of the first case 21.

  Furthermore, according to the electric supercharger 1 of the present embodiment, the motor 7 described above and the compressor 3 having the impeller 2 attached to one end side of the rotating shaft 10a of the rotor 10 are provided. Thereby, the compressed air produced | generated with the impeller 2 rotated at high speed is supplied to an internal combustion engine.

  In the present invention, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention depending on the purpose and application. That is, in the above-described embodiment, the through flow path 50 that extends linearly along the axial direction of the stator 9 is illustrated, but the present invention is not limited to this. For example, the through flow that spirally extends with respect to the axial direction of the stator 9 It may be a road. Even in this case, the stator is cooled in the circumferential direction by the endothermic action when the fluid flows through the spiral through passage.

  Moreover, in the said Example, although the penetration flow path 50 arrange | positioned in the radial direction of the stator core 15 at the centrifugal side of the teeth 15a was illustrated, it is not limited to this, For example, it adjoins the circumferential direction in the radial direction of the stator core 15 It is good also as a penetration channel arranged at the centrifugal side of the middle part of teeth 15a to do. The size, shape, number, location, etc. of the through flow channel 50 are appropriately selected in consideration of the fluid supply amount, the cooling performance of the stator, and the like.

  Moreover, in the said Example, although the annular flow paths 51 and 52 formed by the annular grooves 53 and 54 formed in the clamping surfaces 23a and 24a of the clamping parts 23 and 24 of the housing 8 were illustrated, it is not limited to this. For example, as shown in FIG. 5, instead of or in addition to the annular grooves 53, 54, an annular flow path 51 formed by annular grooves 53 ′, 54 ′ formed on the shaft end surfaces 9 a, 9 b of the stator 9. It may be ', 52'. The size, shape, installation location, open / closed state, and the like of the annular channels 51 and 52 are appropriately selected as long as the branch channel 32 or the second supply channel 44 can be communicated with each through channel 50. The

  Moreover, in the said Example, although the 1st and 2nd discharge flow paths 33 and 45 opened to the exterior of the housing 8 were illustrated, it is not limited to this, For example, a 1st and 2nd discharge flow path is provided in the stator 9. A communicating through channel may be formed, and only one discharge channel may be opened to the outside of the housing 8.

  Moreover, in the said Example, although the fluid bearings 11 and 12 which pivotally support the rotating shaft 10a of the rotor 10 with the oil film of oil were illustrated, it is not limited to this, For example, liquid films other than oil, or gas films, such as air Thus, a fluid bearing that pivotally supports the rotating shaft 10a of the rotor 10 may be used.

  Furthermore, in the said Example, although the electric supercharger 1 act | operated only with the driving force of the motor 7 was illustrated, it is not limited to this, For example, it act | operates with the exhaust energy of an internal combustion engine with the driving force of the motor 7. It may be an electric auxiliary supercharger. Furthermore, in the said Example, although the motor 7 used with the electric supercharger 1 was illustrated, it is not limited to this, For example, it is good also as a motor used with a dental spindle, an air compressor for oxygen supply of an aircraft, etc.

  The foregoing examples are for illustrative purposes only and are not to be construed as limiting the invention. Although the invention has been described with reference to exemplary embodiments, it is to be understood that the language used in the description and illustration of the invention is illustrative and exemplary rather than limiting. As detailed herein, changes may be made in its form within the scope of the appended claims without departing from the scope or spirit of the invention. Although specific structures, materials, and examples have been referred to in the detailed description of the invention herein, it is not intended to limit the invention to the disclosure herein, but rather, the invention is claimed. It covers all functionally equivalent structures, methods and uses within the scope of

  The present invention is not limited to the embodiments described in detail above, and various modifications or changes can be made within the scope of the claims of the present invention.

  The present invention is widely used as a technique related to a motor in which a rotating shaft of a rotor used in an electric supercharger or the like of an internal combustion engine rotates at high speed.

  DESCRIPTION OF SYMBOLS 1; Electric supercharger, 2; Impeller, 3; Compressor, 7; Motor, 8; Housing, 9; Stator, 9a, 9b; Shaft end surface, 10: Rotor, 10a; Rotating shaft, 11; 12; 2nd fluid bearing, 15; Stator core, 15a; Teeth, 16; Coil, 17; Resin mold part, 23; 1st clamping part, 23a; Clamping surface, 24; 2nd clamping part, 24a; First supply channel, 32; branch channel, 44; second supply channel, 50; through channel, 51, 51 '; first annular channel, 52, 52'; second annular channel, 53; , 53 ′; first annular groove, 54, 54 ′; second annular groove.

Claims (6)

A first fluid dynamic bearing that includes a housing, a cylindrical stator mounted in the housing, and a rotor provided on an inner peripheral side of the stator, and rotatably supports a rotating shaft of the rotor in the housing. And a motor provided with the second fluid bearing,
The housing includes a first clamping unit and a second clamping unit that clamps the stator in the axial direction between the first clamping unit and the first clamping unit.
The housing has a first supply flow path having one end opened to the outside of the housing and the other end connected to the first fluid bearing, and one end side of the housing sandwiched by the first supply flow path. A branch flow path that opens to the clamping surface side of the portion, and a second supply flow path that opens at one end side to the clamping surface side of the second clamping portion and is connected to the second fluid bearing at the other end side. And
The stator is formed with a through-flow passage penetrating in the axial direction so as to connect one end side of the branch flow passage and one end side of the second supply flow passage,
The through-flow channel is configured to cool the stator with a fluid flowing in the inside thereof. The through channel is formed along the axial direction of the stator, and a plurality of through channels are formed in the circumferential direction of the stator,
Between the clamping surface of the first clamping part and one shaft end surface of the stator, there is a first annular channel that connects one end side of the branch channel and one end side of the plurality of through channels. Formed,
A second ring connecting the one end side of the second supply flow path and the other end sides of the plurality of through flow paths between the holding face of the second holding portion and the other shaft end face of the stator. The motor according to claim 1, wherein a flow path is formed. The first annular flow path is formed by a first annular groove formed on a sandwiching surface of the first sandwiching portion and one shaft end face of the stator that closes the first annular groove,
The said 2nd annular flow path is formed of the 2nd annular groove formed in the clamping surface of the said 2nd clamping part, and the other axial end surface of the said stator which plugs up the said 2nd annular groove. motor. The stator includes a cylindrical stator core provided with a plurality of winding portions protruding in the circumferential direction on the inner peripheral side, and a coil wound around each of the plurality of winding portions,
4. The motor according to claim 2, wherein each of the plurality of through passages is disposed on a centrifugal side of the winding portion in a radial direction of the stator core. The stator includes a cylindrical stator core having a plurality of winding portions protruding in an inner circumferential side in a circumferential direction, a coil wound around each of the plurality of winding portions, and a circle so as to cover the coils. A resin mold part provided between the winding parts adjacent in the circumferential direction,
The motor according to any one of claims 1 to 4, wherein the resin mold portion is in close contact with an inner surface of the housing. An electric supercharger for supplying compressed air to an internal combustion engine,
A motor according to any one of claims 1 to 5;
And a compressor having an impeller attached to one end of the rotating shaft of the rotor.

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