JP6406310B2 - Electric motor structure and electric motor manufacturing method - Google Patents

Description

  The present invention relates to an electric motor structure and a method of manufacturing an electric motor, and more particularly, a liquid-tight seal made of a synthetic resin that liquid-tightly seals an inner peripheral side of a stator and an inner peripheral side and a part of an outer end of a coil end. It is related with the technique which employs a member.

  Conventionally, electric motors (electric motors) have been used as power sources in various fields. When the electric motor rotates by converting electric energy into kinetic energy, a part of the electric energy is converted into heat energy to generate heat. In particular, various cooling structures have been proposed in order to increase the amount of heat generated as a high-output electric motor mounted on an electric vehicle increases the efficiency of the electric motor.

Patent Document 1 discloses an electric motor in which a storage tank for storing cooling oil is formed on the bottom side in a housing and the bottom side portion of the coil end of the stator is immersed in oil.
Patent Document 2 discloses an electric motor in which an annular cooling passage (cooling chamber) is formed by a cooling cover and a synthetic resin film wall at both end portions of a stator, and the entire coil end is immersed in a refrigerant. Is disclosed.

JP 2014-225971 A JP 2015-33299 A

  The electric motor of Patent Document 1 has a structure in which only the bottom side portion of the coil end of the stator is submerged, and most of the coil end is not submerged, so that an instantaneous temperature rise of the coil end (for example, several seconds) The cooling capacity is insufficient with respect to 200 ° C., and it is difficult to further reduce the size of the electric motor.

  Since the electric motor of Patent Document 2 has a structure in which one end face of the cooling passage is partitioned by a synthetic resin film wall, the coil end slightly vibrates at high speed, so the liquid tightness and durability of the synthetic resin film wall. It is not easy to ensure.

  Since the conventional electric motor does not employ a liquid-tight sealing member that covers the inner periphery of the stator and the pair of coil ends, the structure of the coolant chamber that cools the pair of coil ends is complicated and enlarged. .

  An object of the present invention is to provide an electric motor structure and an electric motor employing a liquid-tight sealing member made of synthetic resin that liquid-tightly seals at least a part of the inner peripheral side of the stator and the inner peripheral side and outer end side of the coil end. It is to provide a method of manufacturing a motor.

The electric motor structure of claim 1 includes a rotor, a pair of bearings that support the rotor, a stator in which a coil is wound around a stator core, and a pair of side housings that are disposed at both end portions in the axial direction. in the structure of the electric motor, a cylindrical portion for accommodating the rotor than the inside inner peripheral surface and has covered the inner peripheral surface of the stator core, of both of the coil end in the stator axial direction inside of the pair of side housings a peripheral surface and an outer end at least part of the pair of annular portion that covers the surface, formed by integrally forming the impregnated portion of the pair impregnated with synthetic resin to the both coil ends synthetic resin fluid-tight for sealing and stop members, and the pre-Symbol 1-one pair of bearing holding surface formed on the annular portion of the pair of side housings and the stator and the one pair of coil end the pair of annular portions and said pair in the impregnation unit It is characterized in that a coolant storage chamber of the pair of annular demarcated to accommodate liquid-tight却液.

  According to this electric motor structure, a liquid-tight sealing member made of a synthetic resin formed by integrally forming the cylindrical portion, the pair of annular portions, and the pair of impregnated portions is provided, and the pair of side housings and the stator are provided. And a pair of coil ends, and the pair of annular portions and the pair of impregnated portions form an annular pair of cooling liquid storage chambers that are liquid-tightly partitioned. Can be simplified and downsized.

  According to a second aspect of the present invention, there is provided the electric motor structure according to the first aspect of the present invention, further comprising fine bubble generating means for generating fine bubbles in the heated coolant near the pair of coil ends.

  In order to generate a fine bubble in the heated coolant near the pair of coil ends by this fine bubble generating means, a high-temperature coolant gas is sealed in the fine bubble at a high pressure. The cooling performance at the time of a rapid heat generation can be ensured.

According to a third aspect of the present invention, there is provided the electric motor structure according to the first aspect, wherein the circulation flow forming means connected to the pair of cooling liquid storage chambers and the heat radiation means for radiating heat from the coolant circulated by the circulation flow forming means. It is characterized by having.

  Since heat dissipating means for dissipating heat from the coolant circulated by the circulating flow forming means is provided, it is possible to circulate the high-temperature coolant that absorbs the heat generated from the coil end to the outside of the coolant housing chamber and to dissipate the heat from the high-temperature coolant. .

According to a fourth aspect of the present invention, there is provided the electric motor structure according to the second aspect of the invention, wherein the fine bubble generating means includes the coil end that vibrates at high speed. Therefore, the configuration of the fine bubble generating means can be simplified.

According to a fifth aspect of the present invention, there is provided the electric motor structure according to the fourth aspect of the invention, wherein the fine bubble generating means includes ultrasonic wave generating means for applying an ultrasonic wave to the coil end . Therefore, the particle size and generation amount of the fine bubbles can be controlled via the ultrasonic waves generated by the ultrasonic wave generation means, and the cooling performance can be controlled.

According to a sixth aspect of the present invention, there is provided the electric motor structure according to the fourth or fifth aspect, wherein the circulation flow forming means connected to the pair of cooling liquid storage chambers removes a part of the fine bubbles from the cooling liquid containing the fine bubbles. It has the fine bubble separation means to isolate | separate, and circulates the cooling fluid after separation to the said cooling fluid storage chamber.

  In order to separate a part of the fine bubbles from the cooling liquid containing the fine bubbles and to circulate the separated cooling liquid to the cooling liquid storage chamber, the fine bubbles having a calorific value are recirculated to the cooling liquid storage chamber. It can suppress and can improve cooling performance.

  According to a seventh aspect of the present invention, there is provided the electric motor structure according to the sixth aspect, wherein the fine bubble separating means is configured to separate a part of the fine bubbles by a centrifugal force. Therefore, the configuration of the fine bubble separating means can be simplified.

The method of manufacturing an electric motor according to claim 8 includes a rotor, a pair of bearings that support the rotor, a stator in which a coil is wound around a stator core, and a pair of side housings that are disposed at both end portions in the axial direction. The stator is set in a mold, a synthetic resin in a molten state is injected into the mold, covers the inner peripheral surface of the stator core, and is inside the inner peripheral surface. A cylindrical portion that can accommodate the rotor, a pair of annular portions that cover at least a part of the inner peripheral surface and the outer end surface of both coil ends, and both of the pair of side housings on the inner side in the stator axial direction. a first step of molding the integrally formed and made of synthetic resin of a liquid-tight for sealing member and the impregnated portion of the pair impregnated with synthetic resin to the coil end, the pair of the opposite ends portions of the stator Side howe Wearing the ring, is capable of accommodating partitions liquid-tightly coolant between the pair of side housings and the stator and the first annular portion of the coil end and the pair of to-and the pair of impregnation portion And a second step of forming a pair of annular coolant storage chambers.

  In the first step, a liquid-tight sealing member made of a synthetic resin formed by integrally forming a cylindrical portion, a pair of annular portions, and a pair of impregnated portions is formed. In the second step, both end sides of the stator In order to form a pair of annular coolant housing chambers that are liquid-tightly partitioned by a pair of side housings, a stator, a pair of coil ends, a pair of annular portions, and a pair of impregnated portions. A pair of cooling liquid storage chambers having a simple structure and capable of being reduced in size can be formed by effectively utilizing the sealing member for sealing.

According to a ninth aspect of the present invention, there is provided a method for manufacturing an electric motor according to the eighth aspect of the invention, wherein the liquid-tight sealing member is cut after the first step and before the second step, and the cylindrical portion is provided with a rotor accommodating portion. And a third step of forming a pair of bearing holding surfaces on the pair of annular portions. Therefore, the liquid-tight sealing member is cut to form a rotor accommodating portion in the cylindrical portion, and a pair of bearing holding surfaces are formed in the pair of annular portions. Compared with the case of forming a pair of bearing holding surfaces , the bearing holding surfaces can be downsized and the manufacturing cost of the bearing holding surfaces can be reduced.

  As described above, according to the electric motor structure of the present invention, a liquid-tight sealing member made of synthetic resin is provided, and an annular pair of cooling liquid storage chambers is formed using the liquid-tight sealing member. Therefore, the structure of the pair of cooling liquid storage chambers can be simplified and downsized. In addition, various effects as described above can be obtained.

According to the method for manufacturing an electric motor of the present invention, a liquid-tight sealing member made of synthetic resin is formed in the first step, and a pair of cooling liquids is accommodated by utilizing the liquid-tight sealing member in the second step. Since the chambers are formed, a pair of cooling liquid storage chambers having a simple structure and capable of being reduced in size can be formed. Further, the bearing holding surface can be downsized, and the manufacturing cost of the bearing holding surface can be reduced.

It is a side surface of the stator core of the electric motor which concerns on Example 1 of this invention. It is sectional drawing of a stator core. It is sectional drawing of the stator which wound the stator coil around the stator core. It is sectional drawing of the sealing member raw material made from a synthetic resin which covers a stator, its inner peripheral surface, and both outer end surfaces. It is sectional drawing of the stator and the synthetic resin sealing member after a cutting process, the bearing with which this is mounted | worn, and a right side housing. It is sectional drawing of a stator, a sealing member, a bearing, and a right side housing. It is sectional drawing of the left side housing main body with which a stator, a sealing member, a bearing, a right side housing, and this are mounted | worn. FIG. 3 is a cross-sectional view of a stator, a sealing member, a bearing, a right side housing, a left side housing main body, a rotor mounted on the right side housing, and a bearing. It is sectional drawing of the electric motor before an end plate mounting | wearing. It is sectional drawing of the electric motor before end plate mounting | wearing, and the end plate mounted | worn with this. It is sectional drawing of an electric motor. It is sectional drawing of the state which accommodated the cooling fluid in a pair of cooling fluid storage chamber of an electric motor. It is sectional drawing of an electric motor and an attached mechanism. It is sectional drawing of the electric motor and attachment mechanism which concern on Example 2 of this invention. It is sectional drawing of the electric motor and attachment mechanism which concern on Example 3 of this invention. It is a block diagram of the pulse drive pump which concerns on Example 4 of this invention. It is a time chart of a drive pulse.

Hereinafter, modes for carrying out the present invention will be described based on examples.
The following description exemplifies what is applied to a permanent magnet synchronous motor whose drive is controlled by a predetermined control unit, and does not limit the present invention, its application, and its use. In the following description, the left side in the figure is the left side and the upper side is the upper side.

First, the electric motor 1 and the attached mechanism 2 attached to the electric motor 1 will be described with reference to FIG. The electric motor 1 is a small high-power motor including a high-performance cooling unit that cools both coil ends 14a and 14b of the stator coil 14 with a coolant C.
The electric motor 1 includes a rotor 3, a pair of bearings 4, 5, a stator 6, a liquid-tight sealing member 7 made of a synthetic resin (for example, polycarbonate), a left side housing 8, and a right side housing. 9, three connecting bolts 10, an annular pair of cooling liquid storage chambers 11 and 12, and a cooling liquid C stored in the pair of cooling liquid storage chambers 11 and 12. The electric motor 1 is attached to the motor support member 13 by fitting the right end portion of the right side housing 9 into the mounting hole 13 a of the motor support member 13.

  The rotor 3 is obtained by externally fixing and fixing a rotor main body 3b (including a plurality of permanent magnets not shown) formed on a rotor shaft 3a to a rotor shaft 3a, and most of the rotor shaft 3a and the rotor main body 3b are formed. It is shaped like a columnar body. A support shaft portion 3c having a small step diameter is formed at the left end portion of the rotor shaft 3a, the support shaft portion 3c is rotatably supported by the bearing 4, and a support shaft portion 3d having a small step diameter is formed at the right end portion of the rotor shaft 3a. The support shaft portion 3d is rotatably supported by the bearing 5, and the tip shaft portion 3e of the support shaft portion 3d protrudes outward. In order to reduce the thermal load on the bearings 4 and 5, large bearings 4 and 5 having an outer diameter of about three times the outer diameter of the support shaft portions 3c and 3d are employed as the bearings 4 and 5.

The stator 6 is made of a laminate of electromagnetic steel sheets, and a plurality of stator coils 14 are wound around a stator core 6a in which a plurality of slots 6b and teeth 6c are formed (see FIG. 3). A plurality of (three-phase) stator coils 14 are wound around a plurality of teeth 6c via a plurality of slots 6b of the stator core 6a, and coil ends 14a and 14b are formed outside both outer ends of the stator core 6a ( (See FIG. 3 ).

  The rotor 3 is rotatably accommodated in a rotor accommodating portion 15 a on the center side of the stator 6, and the electric motor 1 rotates the rotor 3 by a rotating magnetic field generated by flowing a controlled alternating current through the stator coil 14. It is configured.

The liquid-tight sealing member 7 made of synthetic resin includes a cylindrical portion 15 that covers the inner peripheral surface of the stator core 6a, and a pair of annular portions 16 that cover the inner peripheral surface and outer end surfaces of both coil ends 14a and 14b. 17 and a pair of impregnated portions 18a and 18b in which both coil ends 14a and 14b are impregnated with synthetic resin are integrally formed. The left annular portion 16 has an annular thick portion 19 that fills the space between the left end surface of the coil end 14 a and the end plate 8 b of the left side housing 8 without a gap. The right annular portion 17 has an annular thick portion 20 that fills the space between the right end surface of the coil end 14 b and the end wall portion 9 b of the right side housing 9 without any gap.

  The impregnated portions 18a and 18b are portions that are not clearly shown in the drawing, but are portions in which the synthetic resin is impregnated in the gap between the coil wire and the coil wire existing in the coil ends 14a and 14b and other gaps.

A rotor accommodating portion 15a having a circular cross section is formed inside the cylindrical portion 15 of the liquid-tight sealing member 7, and a slight gap is formed between the outer peripheral surface of the rotor 3 and the inner peripheral surface of the rotor accommodating portion 15a. Yes. The pair of annular portions 16, 17 are formed bearing holding surface 21, 22 of slightly larger diameter of the pair than the rotor accommodating portion 15a (bearing holding hole) is 1 to the bearing holding surface 21 and 22 of the pair The pair of bearings 4 and 5 are mounted in an internally fitted state, and are received by the step portions 21 a and 22 a on the cylindrical portion 15 side of the bearing holding surfaces 21 and 22.

The left and right side housings 8 and 9 are made of aluminum alloy. The left side housing 8 includes a cylindrical member 8 a and an end plate 8 b that is a separate end plate 8 b and closes the left end surface of the electric motor 1. An annular protrusion 23 is formed on the inner surface of the end plate 8b, and a bearing retainer 23a for pressing the outer end surface and outer periphery of the outer race of the bearing 4 is formed on the annular protrusion 23.
An annular groove located on the outer peripheral side of the annular projection 23 is formed on the inner surface of the end plate 8b, and an O-ring 24 is attached to the annular groove. The O-ring 24 allows the end plate 8b and the annular thick part 19 to be connected. Is hermetically sealed.

  The cylindrical member 8a of the left side housing 8 is fitted on the left end side portion of the stator 6, and the right end portion of the cylindrical member 8a is fitted on the left end portion of the stator core 6a. The space between the left end surface of the cylindrical member 8a and the end plate 8b is liquid-tightly sealed with an O-ring 25, and the space between the cylindrical member 8a and the outer peripheral surface of the left end portion of the stator core 6a is liquid-tightly sealed with an O-ring 26. Yes. A plurality of coil lead wires 14c extending from the coil end 14a are led out from an opening formed in the cylindrical member 8a.

The right side housing 9 has a cylindrical wall portion 9a and an annular end wall portion 9b formed integrally therewith, and the right side housing 9 is externally fitted to the right end side portion of the stator 6 so that the right side housing 9 The annular end wall portion 9 b is in contact with the annular thick wall portion 20 and the bearing 5.
An O-ring 27 is attached to the annular groove formed in the annular end wall portion 9b, and the space between the annular end wall portion 9b and the annular thick portion 20 is liquid-tightly sealed by the O-ring 27. The position of the outer race of the bearing 5 is regulated by the bearing retainer 28 at the inner peripheral end of the annular end wall 9b.

The left end portion of the cylindrical wall portion 9a is fitted on the right end portion of the stator core 6a, and the O-ring 29 seals the space between the cylindrical wall portion 9a and the stator core 6a in a liquid-tight manner.
Three bolt connecting portions 30 projecting outside the outer periphery of the cylindrical member 8a are formed at three equal positions in the circumferential direction of the outer peripheral portion of the left end plate 8b. Each bolt connecting portion 30 has an axial center of the rotor 3. And a bolt hole 30a parallel to each other is formed. Three bolt connecting portions 31 projecting outside the outer periphery of the cylindrical member 9a are formed at three equal positions in the circumferential direction of the outer peripheral portion of the right cylindrical wall portion 9a. A bolt hole 31a parallel to the shaft center is formed.

  The left three bolt connecting portions 30 and the right three bolt connecting portions 31 are opposed to each other left and right, and the connecting bolts 10 are inserted into the left and right bolt holes 30a and 31a of each set, so The left side housing 8 and the right side housing 9 are firmly connected to each other so as to sandwich the stator 6 by fastening a pair of nuts 30b and 31b screwed together.

  An annular pair of cooling liquid storage chambers 11, 12 includes a pair of side housings 8, 9, a stator 6, a pair of coil ends 14 a, 14 b, and a pair of annular seal members 7 for liquid tightness. It is formed of parts 16, 17 and a pair of impregnated parts 18a, 18b and is liquid-tightly partitioned. A coolant C is stored in the pair of coolant storage chambers 11 and 12. As the coolant C, fluorocarbon is used in this embodiment, but ethanol, water, other hydrocarbons, and the like can be used.

  At the top of the left side housing 8 is formed a cylindrical passage forming portion 34 in which a part of the circulation passage 33 for circulating the coolant C in the left coolant storage chamber 11 is formed. Is formed with a cylindrical passage forming portion 36 in which a part of the circulation passage 35 for circulating the coolant C in the right coolant storage chamber 12 is formed.

Next, the manufacturing method of said electric motor 1 is demonstrated.
Since the manufacturing method of this electric motor 1 is as showing in FIGS. 1-12, it demonstrates easily. First, a stator core 6a as shown in FIGS. 1 and 2 is prepared, and then, as shown in FIG. 3, a plurality of stator coils 14 are wound around the stator core 6a to manufacture the stator 6. The coil ends 14a and 14b protrude from both sides of the stator core 6a in the axial direction.

  Next, as shown in FIG. 4, the stator 6 is accommodated in a predetermined mold of an injection molding machine, and a synthetic resin in a molten state is injected to thereby form a sealing member as a material for the liquid-tight sealing member 7. The sealing member material 7m that is the material 7m and covers the inner peripheral side and both end sides of the stator 6 is formed. The sealing member material 7m includes a cylindrical portion 15m covering the inner peripheral side of the stator core 6a, an annular portion 16m covering the inner peripheral surface and the outer end surface of the left coil end 14a, an inner peripheral surface of the right coil end 14b, and An annular portion 17m covering the outer end surface and impregnated portions 18a and 18b impregnated in both coil ends 14a and 14b are integrally formed. The annular portions 16m and 17m have thick wall portions 19m and 20m. In order to form the impregnated portions 18a and 18b, the outer peripheral sides of the coil ends 14a and 14b are evacuated during injection molding.

Next, as shown in FIG. 5, by cutting the inner peripheral side of the cylindrical portion 15m of the sealing member material 7m, the inner peripheral side of the annular portions 16m and 17m, and the left end surface of the annular portion 16m, the rotor accommodation a cylindrical portion 15 forming a part 15a, an annular portion 16 forming a bearing holding surface 21 to form an annular portion 17 forming a bearing retaining surface 22. An annular thick portion 19 is formed on the annular portion 16, and an annular thick portion 20 is formed on the annular portion 17.

Next, as shown in FIGS. 5 and 6, the bearing 5 is mounted on the bearing holding surface 22, and the right side housing 9 is externally fitted to the right end portion of the stator 6. Next, as shown in FIGS. 7 and 8, the cylindrical member 8 a of the left side housing 8 is externally fitted to the left end portion of the stator 6.
Next, as shown in FIGS. 8 and 9, the bearing 4 is mounted on the support shaft portion 3 c of the rotor 3, and then the rotor 3 is inserted into the rotor housing portion 15 a of the stator 6 from the left side. The rotor 3 and the bearing 4 are mounted by inserting the support shaft portion 3 d into the shaft hole of the bearing 5.

  Next, as shown in FIGS. 10 and 11, after the end plate 8b of the left side housing 8 is mounted, the three connecting bolts 10 are mounted in the bolt holes 30a and 31a of the bolt connecting portions 30 and 31, respectively. The nuts 30b and 31b are fastened to both ends of the bolt 10 to firmly connect the left and right side housings 8 and 9 to the state in which the stator 6 is sandwiched.

  Thus, the left side housing 8, the stator 6, the coil end 14 a, the annular portion 16, and the impregnation portion 18 a form the left annular cooling liquid storage chamber 11 in a liquid-tight manner. 6, the coil end 14 b, the annular portion 17, and the impregnation portion 18 b, the right-side annular cooling liquid storage chamber 12 is formed in a liquid-tight manner. Next, the cooling liquid storage chambers 11 and 12 are filled with the cooling liquid C.

Next, the attachment mechanism 2 attached to the electric motor 1 will be described.
As described above, when the electric motor 1 is driven, the coil ends 14a and 14b vibrate at a high speed, so that fine bubbles having a particle size of nano-order or micron order are generated in the coolant C in the coolant storage chambers 11 and 12. Occur. In this embodiment, the fine bubble generating means 37 is constituted by the coil ends 14a and 14b.

  The coolant C is heated to a high temperature by the heat generated in the coil ends 14a and 14b, and a high-temperature and high-pressure coolant gas compressed to a high pressure by the surface tension is generated inside the fine bubbles generated in the coolant C. It becomes a fine bubble with high density.

  The attachment mechanism 2 circulates the cooling liquid C in the cooling liquid storage chambers 11 and 12 to an external separation and cooling system, separates most of the fine bubbles from the cooling liquid C, and determines the cooling liquid ratio after the separation. A high coolant (high density coolant) is circulated in the coolant storage chambers 11 and 12, and most of the fine bubbles contained in the coolant (low density coolant) having a high ratio of fine bubbles and a low coolant ratio are removed. After being ruptured by ultrasonic waves, the high-temperature coolant is cooled by the cooling means, and the cooled coolant is circulated again to the coolant storage chambers 11 and 12.

  As shown in FIG. 13, the auxiliary mechanism 2 includes a circulating flow forming means 40 that forms a circulating flow in the cooling liquid C in the cooling liquid storage chambers 11 and 12, and fine bubble separation incorporated in the circulating flow forming means 40. Means 41, a plurality of ultrasonic generators 42 that burst most of the separated fine bubbles, and a cooling means 43 that cools the high-temperature coolant gas and coolant C after bursting the fine bubbles. The ultrasonic generator 42 and the cooling means 43 constitute a heat radiating means 38 for radiating heat from the coolant C.

  The circulating flow forming means 40 is constituted by a centrifugal pump having a large-diameter short cylindrical case 44, an impeller 45 accommodated in the case 44, and a drive motor 46, and on the upper side of the impeller 45 in the case 44. A separation space 47 for swirling flow formation and fine bubble separation is provided. The impeller 45 is flat and has a large diameter in order to form a high-speed swirling flow.

Circulation passages 3 3 and 35 communicated with the cooling liquid storage chambers 11 and 12 are connected to the cylindrical portion 44a projecting from the lower surface side central portion of the case 44, and the cooling liquid C sucked into the cylindrical portion 44a is The impeller 45 that is rotated at a high speed is pushed out to the outer peripheral side to form a high-speed swirling flow at the outer peripheral portion in the case 44. Circulation passages 48 and 49 communicating with the cooling liquid storage chambers 11 and 12 are formed at portions adjacent to the circulation passages 3 3 and 35, respectively. The circulation passages 48 and 49 are connected to the outer periphery near the upper end of the case 44. ing. The cooling fluid housing chamber 11 between the passage forming component of the circulation passage 3 3 of the passage forming portion 34 and the circulation passage 48 is partitioned, between the passage forming component of the passage forming component 36 and the circulation passage 49 of the circulation path 35 The cooling liquid storage chamber 12 is partitioned.

  The fine bubble separating means 41 moves the high density cooling liquid having a low ratio of fine bubbles to the outer peripheral side by centrifugal force acting on the high-speed swirling flow of the cooling liquid in the case 44, and the low density cooling having a high ratio of fine bubbles. By moving the liquid to the inner peripheral side, most of the fine bubbles are separated.

  A short cylindrical cooling case 51 is connected to the upper surface of the case 44 via a connecting cylinder 50, and an annular cooling liquid chamber 52 is formed in the cooling case 51. On the upper surface of the cooling case 51, for example, four sets of ultrasonic generators 42 for irradiating the low-density cooling liquid in the cooling liquid chamber 52 with ultrasonic waves for bursting fine bubbles are attached. A cooling water jacket 43 that covers the portion is provided, and cooling water is circulated through the cooling water jacket 43. In addition, the high-density coolant flows from the outer periphery of the lower surface of the cooling case 51 to the outer periphery of the upper end of the separation space 47 in the case 44 through the reflux passages 53 and 54.

  When the low-density coolant in the central portion of the separation space 47 flows into the coolant chamber 52 through the connection tube 50 and the fine bubbles are destroyed by the ultrasonic waves irradiated from the ultrasonic generator 42, the fine bubbles Is decomposed into a coolant gas and a high-temperature coolant, which are effectively cooled by the coolant in the coolant jacket 43, and the cooled coolant returns to the separation space 47 from the reflux passages 53 and 54. The cooled cooling liquid is mixed with the high-density cooling liquid in a high-speed swirling state and circulates from the circulation passages 48 and 49 to the cooling liquid storage chambers 11 and 12.

Next, the operation and effect of the electric motor 1 including the attachment mechanism 2 will be described.
According to this electric motor 1, a liquid-tight sealing member 7 made of synthetic resin is provided, in which a cylindrical portion 15, a pair of annular portions 16, 17 and a pair of impregnation portions 18a, 18b are integrated. A pair of coolings that are liquid-tightly partitioned by the side housings 8, 9 and the stator 6, a pair of coil ends 14a, 14b, a pair of annular portions 16, 17 and a pair of impregnated portions 18a, 18b. Since the liquid storage chambers 11 and 12 are formed, the structure of the cooling liquid storage chambers 11 and 12 can be simplified and downsized.

  In order to generate fine bubbles in the heated coolant near the pair of coil ends 14a and 14b by the fine bubble generating means 37, a high-temperature coolant gas is confined at high pressure in the fine bubbles. Thus, by utilizing the phase change of the coolant, it is possible to ensure the cooling performance at the time of instantaneous rapid heat generation immediately after the start in the case where the drive wheels of the automobile are driven by the electric motor 1.

In order to provide the heat radiating means 38 for radiating heat from the cooling liquid C circulated by the circulating flow forming means 40, the high-temperature cooling liquid C absorbing heat generated from the coil ends 14a, 14b is circulated outside the cooling liquid storage chambers 11, 12. The heat can be dissipated from the high-temperature coolant C.
Since the fine bubble generating means 37 includes end coils 14a and 14b that vibrate at high speed, the configuration of the fine bubble generating means 37 can be simplified.

  The circulating flow forming means 40 has the fine bubble separating means 41 for separating a part of the fine bubbles from the cooling liquid C containing the fine bubbles and circulates the separated cooling liquid C to the cooling liquid storage chambers 11 and 12. A part of the fine bubbles is separated from the cooling liquid C including the fine bubbles, and the separated cooling liquid C is circulated to the cooling liquid storage chambers 11 and 12, so that the fine bubbles having the heat amount are stored in the cooling liquid storage chambers 11 and 12. It is possible to suppress recirculation and improve the cooling performance.

  Since the fine bubble separation means 41 is configured to separate a part of the fine bubbles by centrifugal force, the configuration of the fine bubble separation means 41 can be simplified.

  In the method of manufacturing the electric motor 1, a liquid-tight sealing member 7 made of a synthetic resin, in which a cylindrical portion 15, a pair of annular portions 16, 17 and a pair of impregnation portions 18a, 18b are integrally formed, is formed. Next, a pair of side housings 8 and 9, a pair of stators 6, a pair of coil ends 14 a and 14 b, a pair of annular portions 16 and 17, and a pair of impregnated portions 18 a and 18 b are disposed at both ends of the stator 6. In order to form a pair of closely spaced annular coolant chambers 11, 12, the coolant chambers 11, 12 can be made simple and downsized by effectively utilizing the liquid-tight sealing member 7. Can be formed.

Since the liquid-tight sealing member 7 is cut to form the rotor accommodating portion 15a in the cylindrical portion 15 and to form the pair of bearing holding surfaces 21 and 22 in the pair of annular portions 16 and 17, a pair of as compared with the case of forming the bearing retaining surface 21, 22 of the pair to the side housing 8,9, a bearing holding surface 21 and 22 can be miniaturized to reduce the manufacturing cost of the bearing holding surface 21 and 22.

The electric motor 1 and its attachment mechanism 2 according to the second embodiment will be described with reference to FIG.
The same components as those of the electric motor 1 according to the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different configurations will be described. In order to increase the volume of the cooling liquid storage chambers 11A and 12A, the outer diameters of the O-rings 24 and 27 are reduced, and the outer diameters of the annular thick portions 19A and 20A are reduced to the same extent as the outer diameters of the O-rings 24 and 27. It has become.

  In addition, when a sufficient amount of fine bubbles are not generated due to the minute vibration of the coil ends 14a and 14b, a plurality of ultrasonic wave generating means 39a for applying ultrasonic waves to the coil end 14a is provided as needed and the coil A plurality of ultrasonic wave generating means 39b for applying ultrasonic waves to the end 14b may be provided. Through the ultrasonic waves generated by the ultrasonic wave generation means 39a, 39b, the particle size, generation amount, etc. of the fine bubbles can be controlled, and the cooling performance can be controlled.

  Further, if necessary, a plurality of wire mesh grid electrodes 55 are arranged in a separation space 47 in the case 44 in order to promote separation of fine bubbles in the coolant C, and direct current is applied to the grid electrodes 55. You may comprise so that a positive predetermined voltage may be applied from a power supply means. Since the fluorocarbon is used as the cooling liquid C, the fine bubbles are negatively charged. Therefore, the fine bubbles are attracted toward the grid electrode 55 by electric force, so that the separation of the fine bubbles can be promoted. In this case, the fine bubble generating means 37 is composed of the coil ends 14a and 14b and the ultrasonic generating means 39a and 39b.

An electric motor 1 and its attachment mechanism 2 according to Embodiment 3 will be described with reference to FIG.
The same components as those of the electric motor 1 according to the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different configurations will be described.

  As shown in FIG. 15, in order to increase the cooling capacity for cooling the stator 6, a graphene sheet laminate 61 in which a plurality of graphene sheets 60 excellent in heat conduction are laminated is wound around the outer peripheral surface of the stator 6, and the graphene sheet laminate In order to press 61 against the stator 6, a steel cylinder 62 externally fitted to the stator 6 and the graphene sheet laminate 61, which is formed by bolting a semi-cylindrical two-part body, is provided. Then, one end portion of the graphene sheet laminate 61 is led out to the outside of the steel cylinder 62, and is brought into contact with a heat sink (not shown) and fastened by a pressing plate 63 and a plurality of bolts 64.

Instead of the centrifugal pump employed in the circulating flow forming means 40, the following pulse drive pump 70 may be employed.
As shown in FIG. 16, a passage 72 through which a coolant C flows is formed inside a cylindrical body 71 made of synthetic resin, and a plurality of wire mesh-like grid electrodes 73 a to 73 a crossing the passage 72 are formed inside the cylindrical body 71. 73i are fixed to the cylindrical body 71 at predetermined intervals in the coolant flow direction. A conducting wire 74 for applying a predetermined positive pulse voltage is connected to each of the plurality of grid electrodes 73 a to 73 i, and these conducting wires 74 are electrically connected to the drive control unit 75.

The drive control unit 75 is configured to repeatedly apply drive pulses 76a to 76i having a predetermined voltage (for example, about 60 to 100V) as shown in FIG. 17 to the plurality of grid electrodes 73a to 73i at short time intervals. . When fluorocarbon is adopted as the cooling liquid, since the fluorocarbon has a negatively charged micelle structure, the fine bubbles are negatively charged.

  Therefore, when the drive pulses 76a to 76i as shown in FIG. 17 are applied to the grid electrodes 73a to 73i, the fine bubbles are sequentially driven to the downstream side by the electric force acting between the grid electrodes 73a to 73i. At the same time, the coolant other than the fine bubbles also flows with the fine bubbles. FIG. 16 shows the coolant containing fine bubbles by sequentially repeating the application of the drive pulses 76a to 76i in the second column after a predetermined short time from the application of the drive pulses 76a to 76i in the first column. Can flow to the right. That is, a coolant pump that pressurizes and flows the coolant can be configured.

The number of grid electrodes 73a to 73i is merely an example, more grid electrodes may be provided, and the spacing between the grid electrodes is also an example and is appropriately set. The drive pulse applied to the grid electrode is also an example, and is not limited to the above.

  When the above-described pulse-driven pump 70 is employed, a conical cyclone is employed as the fine bubble separating means for separating fine bubbles, and a high-speed flow of the coolant formed by the pump 70 is introduced into the cyclone and centrifuged. It can be separated into a high density cooling liquid and a low density cooling liquid by the action of force. In order to rupture the fine bubbles in the low-density cooling liquid, ultrasonic waves may be employed as in the first embodiment. As a cooling means for cooling the hot cooling liquid, cooling water is used as in the first embodiment. A jacket or air-cooled fins may be used.

  Next, an example in which the above embodiment is partially changed will be described.

1 ) Instead of the cooling water jacket 43 of the accessory mechanism 2, a plurality of air cooling fins are integrally formed on the outer peripheral portion and the upper surface portion of the cooling case 51, and the cooling gas and cooling liquid in the cooling case 51 are cooled by air cooling. You may comprise so that it may cool.

2 ) The fluorocarbon used in the coolant is hydrofluoroether (HFE),
Hypochlorous acid (HFO), hydrofluorocarbon (HFC), perfluorocarbon (PFC) and the like are desirable. Alternatively, an alcohol-based liquid may be used as a base, and HFE may be mixed therein to employ a multistage boiling type coolant.

3 ) As fine bubble separation means, it is possible to separate fine bubbles by using the principle of the pulse drive pump 70 of FIG.
In this case, for example, in the pulse-driven pump 70 of FIG. 16, if a plurality of semicircular grid electrodes are provided only in the upper half of the passage in the cylinder 71, a plurality of low density cooling liquids with a high ratio of fine bubbles are obtained. The high density cooling liquid with a low ratio of fine bubbles flows in the lower half side by being sucked to the grid electrode side (upper half side) and driven in the flow direction, so the low density cooling liquid and the high density cooling liquid are separated. can do.

4 ) As shown in FIG. 4, when the molten synthetic resin is injected, the outer peripheral side of the coil ends 14a, 14b is injection-molded without evacuation, and the inner peripheral vicinity and the outer end surface of the coil ends 14a, 14b The thin impregnated portions 18a and 18b may be formed only in the portions, and the cooling liquid may be permeated from the outer peripheral side into most of the coil ends 14a and 14b. By allowing the coolant to penetrate between the coil wires, the cooling performance of the stator coil 14 can be enhanced.

5 ) The present invention can be similarly applied to an electric motor that cools the coil ends 14a, 14b with the coolant C circulated in the coolant chambers 11, 12 without generating the fine bubbles. In this case, the fine bubble generating means 37, the fine bubble separating means 41, the fine bubble separating space 47, the ultrasonic generator 42, the ultrasonic generating means 39a, 39b and the like are omitted.

6 ) In addition, those skilled in the art can implement the present invention by adding various modifications without departing from the spirit of the present invention, and the present invention includes such modifications.

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Attached mechanism 3 Rotor 4, 5 Bearing 6 Stator 6a Stator core 7 Liquid-tight sealing member 8, 9 Side housing 11, 12 Coolant accommodating chamber 11A, 12A Coolant accommodating chamber 14 Stator coils 14a, 14b Coil end 15 Cylindrical portion 15a Rotor accommodating portion 16, 17 Annular portion 18a, 18b impregnated portion 21, 22 Bearing holding surface 37 Fine bubble generating means 38 Heat radiating means 39a, 39b Ultrasonic generating means 40 Circulating flow forming means 41 Fine bubble separating means 70 Pulse Drive type pump 73a-73i Grid electrode

Claims (9)

In the structure of an electric motor having a rotor, a pair of bearings that support the rotor, a stator in which a coil is wound around a stator core, and a pair of side housings disposed at both end portions in the axial direction,
A cylindrical portion that houses the rotor than the inside inner peripheral surface and has covered the inner peripheral surface of the stator core, the inner peripheral surface and the outer end surface of both of the coil end in the stator axial direction inside of the pair of side housings an annular portion of a pair of covering at least a portion, a pair integrally formed comprising synthetic resin fluid-tight for sealing member and the impregnated portion of the impregnated synthetic resin to the both coil ends,
And the bearing holding surface of a pair of the ring section of the front Symbol pair,
The pair of side housings and the stator the pair of coil end and the pair annulus and a pair of annular demarcated to accommodate liquid-tight coolant in impregnation of said pair An electric motor structure comprising a cooling liquid storage chamber.   2. The electric motor structure according to claim 1, further comprising fine bubble generating means for generating fine bubbles in the heated coolant near the pair of coil ends. Electric according to claim 1, comprising: the respective connected circulating flow formation means to the cooling liquid receiving chamber of the pair, and a heat radiating means for radiating the cooling liquid circulating through the circulation flow forming means Motor structure. 3. The electric motor structure according to claim 2, wherein the fine bubble generating means includes the coil end that vibrates at high speed. 5. The electric motor structure according to claim 4, wherein the fine bubble generating means includes ultrasonic generating means for applying ultrasonic waves to the coil end . The circulation flow forming means connected to each of the pair of cooling liquid storage chambers has a fine bubble separating means for separating a part of the fine bubbles from the cooling liquid containing the fine bubbles, and a separation for separating a part of the fine bubbles. 6. The electric motor structure according to claim 4, wherein the cooling liquid is circulated to the cooling liquid storage chamber.   The electric motor structure according to claim 6, wherein the fine bubble separating means is configured to separate a part of the fine bubbles by centrifugal force. In a method of manufacturing an electric motor having a rotor, a pair of bearings that support the rotor, a stator in which a coil is wound around a stator core, and a pair of side housings disposed at both end portions in the axial direction,
Set the stator into the mold, this into the mold by injecting a molten synthetic resin, the inner peripheral surface and has covering can accommodate the rotor from inside the inner peripheral surface of the cylindrical portion of the stator core If, with the pair of side inner peripheral surface of both of the coil end in the stator axial direction inside of the housing and an outer end face a pair of annular portion covering at least a portion of, impregnated with synthetic resin to the both coil end A first step of molding a liquid-tight sealing member made of synthetic resin formed integrally with a pair of impregnated parts;
By mounting the pair of side housings at both end portion of the stator, between the pair of side housings and the stator and the annular portion of the coil end and said pair of said pair and the pair of impregnation portion And a second step of forming a pair of annular cooling liquid storage chambers partitioned so as to be capable of storing the cooling liquid in a liquid-tight manner. After the first step and before the second step, the liquid-tight sealing member is cut to form a rotor accommodating portion in the cylindrical portion, and a pair of bearing holding surfaces is provided on the pair of annular portions. The method for manufacturing an electric motor according to claim 8, further comprising a third step of forming.