JP2005012989A - Cooling structure of stator in rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To sufficiently cool a stator coil of a motor with cooling coil. <P>SOLUTION: The stator core 2000 of the motor includes a slot for housing the stator coil 2012 in the stator core 2000, and the cooling oil passage of a direction perpendicular to a rotary central axis communicating with the outer periphery of the stator core 2000. Thus, the cooling oil is supplied from the outer circumferential direction of the stator core 2000 into the slot, the cooling coil supplied to the slot is permeated into air gaps of copper wires for constituting the stator coil housed in the slot to cool the stator coil. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a structure of a rotary electric machine such as a motor, and more particularly to a cooling structure of a liquid-cooled rotary electric machine mounted on a vehicle such as an automobile.

  A motor or a generator mounted on a vehicle such as an automobile has a rotor (rotor) and a stator core that is disposed around the rotor and is wound with a stator coil. The motor energizes the stator coil to obtain a rotational force, and the generator extracts the current flowing through the stator coil by the rotation of the rotor. When a current flows through the stator coil during rotor rotation, the stator core and the stator coil generate heat. Such heat generation affects the magnetic flux penetrating the inside of the motor or the generator, and decreases the operation efficiency. In order to maintain the operation efficiency, it is necessary to cool the motor and the generator.

  Such a motor or generator is mounted on the vehicle in a form covered with a housing. Therefore, for cooling the motor and the generator, a cooling medium passage is provided in the housing, and cooling with a refrigerant passing through the passage, that is, liquid cooling is often applied. At this time, since it is necessary to ensure insulation of the coil of the electric motor, cooling is performed by a method of flowing cooling water through a refrigerant path provided in a non-contact portion with the coil in the housing or in the vicinity of the heat generating portion. It is performed by a method of flowing or spraying an insulating machine oil or the like. In the method using an insulating refrigerant such as machine oil, it is not necessary to provide a refrigerant path in the housing while maintaining the insulating property. Therefore, the housing can be downsized and the refrigerant is supplied in the vicinity of the heat generating portion. Because it can, it is excellent in terms of large cooling capacity.

  Moreover, since the motor and the generator have a structure in which a rotatable rotor is housed in an annular stator, there are many air layers inside. Since the stator usually has a laminated structure in which a plurality of thin steel plates are stacked, the stator itself has many air layers. This air layer has a heat insulating effect. If such an air layer is eliminated, it is possible to improve the thermal conductivity in the motor or generator.

  Techniques relating to cooling for suppressing such heat generation are disclosed in the following publications.

  Japanese Patent Laid-Open No. 11-318055 (Patent Document 1) discloses a cooling control device for a rotating electrical machine that efficiently transfers heat in the rotating electrical machine to a housing or the like and dissipates heat to the outside. This cooling control device is a cooling control for a rotating electrical machine including a ring-shaped stator having a plurality of slots and teeth alternately formed on the inner peripheral surface and fitted with a coil, and a rotatable rotor disposed on the inner peripheral portion of the stator. A medium supply unit that supplies a cooling medium from the outer peripheral surface of the stator toward the inner peripheral surface, a medium storage unit that collects and temporarily stores the cooling medium from the inside of the stator, a medium supply unit, and a stator A control unit that circulates the cooling medium with the medium storage unit and controls the cooling medium in the stator to a predetermined amount or less.

  According to the cooling control device disclosed in Patent Document 1, a cooling medium can be directly supplied to a coil and a stator, which are heat generation sources, and the cooling medium passes through the coil and the stator by eliminating an air layer in the stator portion. Thus, the generated heat can be efficiently transmitted to the outside of the stator. Further, since the continuous contact between the cooling medium and the rotor can be eliminated by controlling the amount of the cooling medium to a predetermined amount or less, heat transfer is efficiently performed in the rotating electrical machine without forming a new heat source. , Can dissipate heat.

  Japanese Patent Laid-Open No. 59-2222057 (Patent Document 2) discloses a rotating electrical machine including a liquid cooling stator that is resistant to vibration and heating. This rotating electrical machine includes a thin plate laminated cylindrical stator core having a plurality of axial slots on the inner peripheral surface side in which a stator winding is housed, and an iron core provided at an axial end of the stator core. An end plate having an end surface having substantially the same shape as the end surface, and an end plate assembly comprising a seal ring extending in a substantially cylindrical shape on the inner peripheral surface side of the end plate on the opposite side of the iron core; A liquid-tight stator frame that forms a vacant end of the wire ring that covers the end of the ring ring by contacting the end of the seal ring of the assembly, and a liquid inlet / outlet that supplies and discharges the cooling liquid to the vacant end of the wire ring A rotary cooling machine comprising a liquid cooling stator comprising an aggregate formed on the inner peripheral surface of the iron core and the inner peripheral surface of the seal ring and a barrier layer made of a glass composite containing glass as a component, And a thermal expansion relaxation member that is softer than both of them. It was.

According to the rotating electrical machine disclosed in Patent Literature 2, a softer thermal expansion relaxation member is interposed between the stator core and the end plate assembly, and the seal ring of the end plate assembly is inserted from the inner periphery side of the stator core. Since the barrier layer made of the glass composite is formed on the inner peripheral surface, it is possible to realize a highly reliable and highly efficient rotating electric machine that prevents liquid leakage due to the barrier layer breakage while reducing the gap with the rotor.
Japanese Patent Laid-Open No. 11-318055 JP 59-2222057

  However, the rotating electrical machine disclosed in the above-described patent document has the following problems.

  In the cooling control device for a rotating electrical machine disclosed in Patent Document 1, the rotating electrical machine includes an annular stator in which a plurality of slots and a plurality of teeth are alternately formed on an inner peripheral surface inside a cylindrical housing, and a center And a rotor having a shaft functioning as an output shaft. Such a stator and rotor are formed by laminating a plurality of thin electromagnetic steel sheets processed into a predetermined shape by pressing or the like. Since the stator is configured by laminating a plurality of thin electromagnetic steel plates formed by pressing or the like, a gap of about 1/100 mm is formed between the electromagnetic steel plates. The coil portion is cooled while cooling oil penetrates into the gap. However, the supply of the cooling oil for the stator in such a rotating electric machine uses only a slight gap between the electromagnetic steel sheets, and cannot supply sufficient cooling oil for cooling the stator coil and the stator core. Absent.

  In the rotating electrical machine disclosed in Patent Document 2, the stator wire ring (stator coil and stator coil end) is surrounded in a liquid-tight manner by the stator frame, the seal ring portion, and the blocking layer, and the liquid inlet / outlet of the stator frame is provided. The cooling liquid is supplied / discharged through the slot space of the stator (stator) to cool the stator coil and the stator coil end. However, in this way, enclosing the entire portion of the stator including the stator wire ring in a liquid-tight manner makes the structure very complicated and requires a very large number of man-hours for production. Become. For this reason, it leads to a cost increase. Also, processing in this way increases the weight of the electric motor, and the increase in the vehicle weight ultimately leads to a deterioration in the fuel consumption of the vehicle.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a simple structure in a rotating electrical machine that cools a stator by supplying a cooling medium from outside the stator. It is another object of the present invention to provide a stator cooling structure in a rotating electrical machine that can efficiently cool a stator.

  A cooling structure in a rotating electrical machine according to a first aspect of the present invention includes a hollow cylindrical stator in which a plurality of slots and teeth are alternately formed, and a coil is mounted in the slot, and an inner peripheral side of the hollow portion of the stator. The stator in the rotating electric machine composed of the freely rotatable rotor is cooled. In this cooling structure, the stator core is provided with a communication hole that communicates the slot and the outer peripheral surface of the stator.

  According to the first invention, the stator has a hollow cylindrical shape, and the rotor is disposed on the inner peripheral side of the hollow portion of the stator. The rotor is rotated by a magnetic field generated when an electric current is passed through the stator coil, and becomes a driving force of the vehicle, for example. The stator coil is wound around a plurality of slots provided in the stator. The stator is a hollow cylinder, and the slot is provided so as to open on the inner peripheral surface of the stator. In the stator cooling structure according to the first aspect of the present invention, a communication hole that communicates the slot of the stator and the outer peripheral surface of the stator is provided. For example, a cooling medium passage is provided in the outer housing of the stator, and cooling oil, which is a cooling medium, is supplied from the passage to a slot in which the stator coil is mounted through a communication hole. In this way, since the communication hole communicates with the slot on the inner peripheral side from the outside on the outer peripheral side of the stator, the cooling oil can be positively supplied to the slot. As a result, in a rotating electrical machine that supplies cooling oil to the stator from the outside of the stator, the stator can be efficiently cooled with a simple structure. Note that the rotating electric machine includes an electric motor such as a motor, a generator such as a generator and an alternator, and the like.

  In the cooling structure for a rotating electrical machine according to the second invention, in addition to the structure of the first invention, the stator core is formed by laminating a number of thin steel plates having a hollow disk shape. Each steel plate has a plurality of slots and teeth alternately formed, and in each steel plate, at least one of the plurality of slots is formed by a notch portion connecting the outer periphery of the slot and the outer periphery of the steel plate. A communication hole is formed.

  According to the second invention, in general, when a stator is formed by laminating a large number of thin steel plates such as silicon, each thin steel plate has a hollow disk shape and faces the hollow portion. A number of slots around which the coil is wound are opened. Furthermore, it has a notch part connected to a slot from the outer periphery of a hollow disc. Cooling oil is supplied to the inside of the slot from the outer peripheral direction of the stator through this notch, and the stator coil wound around the slot is cooled. At this time, the cooling oil permeates the air layer, which is a gap between a large number of strands (copper wires) constituting the stator coil, and the temperature rise due to Joule heat generated by current flowing through the stator coil is suppressed by the cooling oil. Is done.

  In the cooling structure for the rotating electrical machine according to the third aspect of the invention, in addition to the configuration of the second aspect, the notch formed in each steel plate does not affect the magnetic flux generated by the current flowing through the stator coil. Is formed.

  According to the third invention, the notch is provided in the stator, but at this time, the notch is provided so as not to affect the magnetic flux generated in the stator core by passing a current through the stator coil. And the performance of the generator is not degraded.

  In the cooling structure in the rotating electrical machine according to the fourth invention, in addition to the configuration of any one of the first to third inventions, the cooling medium is communicated from the outer peripheral side to the inner peripheral side of the stator core through the communication hole, The cooling medium is permeated into the gaps of the wire forming the stator coil in the slot.

  According to the fourth aspect of the invention, the cooling oil permeates the air layer, which is a gap between a number of copper wires constituting the stator coil, and the temperature rise due to Joule heat generated by current flowing through the stator coil is suppressed by the cooling oil. Is done.

  A cooling structure in a rotating electrical machine according to a fifth aspect of the present invention is a hollow cylindrical stator in which a plurality of slots and teeth are alternately formed, and a coil is mounted in the slot, and is disposed on the inner peripheral side of the hollow portion of the stator. The stator in the rotating electric machine composed of the freely rotatable rotor is cooled. In this cooling structure, the stator core is provided with a communication space that communicates the coil and the outer peripheral surface of the stator core.

  According to the fifth invention, the stator has a hollow cylindrical shape, and the rotor is disposed on the inner peripheral side of the hollow portion of the stator. The rotor is rotated by a magnetic field generated when an electric current is passed through the stator coil, and becomes a driving force of the vehicle, for example. The stator coil is wound around a plurality of slots provided in the stator. The stator is a hollow cylinder, and the slot is provided so as to open on the inner peripheral surface of the stator. In the stator cooling structure according to the fifth aspect of the present invention, a communication space that communicates the stator coil and the outer peripheral surface of the stator is provided. For example, a spacer is provided between a number of thin steel plates constituting the stator core, and a gap (gap) is provided between the thin steel plates. Cooling oil as a cooling medium is supplied to the stator coil through this communication space. In this way, a large gap can be provided (as long as it does not affect the magnetic path formation) rather than a gap of about 1/100 mm of the thin steel plate as in Patent Document 1, so that the cooling oil passage is enlarged. can do. Therefore, since the communication space is configured to communicate with the stator coil on the inner peripheral side from the outer peripheral side of the stator, the cooling oil can be positively supplied to the stator coil. As a result, in a rotating electrical machine that supplies cooling oil to the stator from the outside of the stator, the stator can be efficiently cooled with a simple structure.

  In the cooling structure for the rotating electrical machine according to the sixth invention, in addition to the configuration of the fifth invention, the communication space is a gap between the thin steel plates, and the stator core has a number of thin plates having a hollow disk shape. Each of the thin steel plates is configured by laminating steel plates, and a spacer for providing a gap between the thin steel plates is provided between the thin steel plates.

  According to the sixth invention, the gap that is the communication space is formed simply by inserting the spacer between the thin steel plates, so that the communication space for supplying the cooling oil to the stator coil can be formed with a simple configuration. .

  In the cooling structure for the rotating electrical machine according to the seventh invention, in addition to the configuration of the sixth invention, the spacer is provided between the thin steel plates so as to be symmetrical with respect to the cross-sectional shape of the stator core. is there.

  According to the seventh invention, since the spacer is arranged so as to be point-symmetric or line-symmetric in the cross-sectional shape of the stator core having a circular shape, there is no occurrence of play due to the spacer inserted between the thin steel plates. .

  In the cooling structure for a rotating electrical machine according to the eighth invention, in addition to the structure of the seventh invention, a plurality of communication spaces are provided, at least two spacers are provided in the cross section of the stator core, and the spacers are in the cross section of the stator core. The center of rotation of the rotating electrical machine is the center of the point object. The cooling structure further includes a connecting member that connects the spacers that form the different communication spaces at the same angle in the point object.

  According to the eighth invention, for example, the communication space is provided at three locations, and the stator core is divided into four. Further, for example, in the cross section of the stator core, spacers are provided every 60 degrees from the vertically upper position which is the reference position, and six spacers are used between the thin steel plates to form one gap. The connecting member connects a plurality of spacers which are spacers at the same angle and form different gaps (in this example, there are three gaps which are communication spaces, so three spacers). In this example, there are six connecting members. By connecting the spacers using such connecting members and connecting the connecting members also to the thin steel plates, a stator core having a gap for allowing cooling oil to communicate can be formed with a simple structure.

  In the cooling structure for a rotating electrical machine according to the ninth invention, in addition to the structure of the eighth invention, the spacer, the connecting member, and the thin steel plate are joined by welding.

  According to the ninth invention, since the spacer, the connecting member, and the thin steel plate are joined by welding, the stator core can be formed with a simple configuration and a strong configuration can be obtained.

  In the cooling structure in the rotating electrical machine according to the tenth invention, in addition to the configuration of any one of the fifth to ninth inventions, the cooling medium is communicated from the outer peripheral side to the inner peripheral side of the stator core through the communication space, The stator coil in the slot is cooled.

  According to the tenth invention, the cooling oil is supplied to the stator coil, and the temperature rise due to the Joule heat generated by the current flowing through the stator coil is suppressed by the cooling oil.

  In the cooling structure for a rotating electrical machine according to the eleventh invention, in addition to the configuration of the fourth or tenth invention, the cooling medium is cooling oil, and in the cooling structure for the rotating electrical machine according to the twelfth invention, In addition to the configuration of the invention, the cooling oil is an automatic transmission fluid.

  According to the eleventh invention, the stator can be cooled by the cooling oil that is liquid, and according to the twelfth invention, the stator can be cooled by the automatic transmission fluid (ATF) of the automatic transmission.

<First Embodiment>
The first embodiment of the present invention will be described below with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  In the following description, the rotating electrical machine in the present invention is described as an electric motor, but the present invention is not limited to the electric motor and is not applied. For example, you may make it apply to generators, such as a generator and an alternator.

  With reference to FIG. 1, the electric motor mounted in the vehicle which concerns on the 1st Embodiment of this invention is demonstrated. As shown in FIG. 1, the vehicle is mounted with the rotating shaft horizontal or substantially horizontal.

  FIG. 1 shows a cross-sectional view of such an electric motor. This electric motor includes a rotor 1010 that is rotatably supported by two bearings 1020 and a stator portion that is installed in the outer circumferential direction of the rotor 1010. The rotor 1010 is supported by a bearing 1020, rotates about the rotation shaft 1000, and transmits rotational torque to the power train of the vehicle.

  A stator core 2000 is provided at a position corresponding to the rotor 1010 via a slight gap. A coil is wound around the stator core 2000 in a slit provided so as to penetrate the stator core 2000 in a direction parallel to the rotation axis. When a current is passed through the coil, the stator core 2000 generates a magnetic field for rotating the rotor 1010. An end portion of a coil wound around the stator core 2000 is formed as a stator coil end 2010. These components, which are the rotating shaft 1000, the rotor 1010, the bearing 1020, the stator core 2000, and the stator coil end 2010, are housed in the housing 3000.

  The housing 3000 is provided with a cooling oil supply unit 3100 that supplies cooling oil to the stator core 2000 so as to surround the stator core 2000. The cooling oil supply unit 3100 supplies, for example, cooling oil supplied by an oil pump to a cooling oil path that is a communication path provided in the stator core 2000 through an oil path (not shown). The cooling oil supplied to the slot penetrates into the gap of the copper wire in the slot and cools the copper wire. As a result, the stator core 2000 is cooled by the cooling oil such as ATF supplied to the slots of the stator core 2000 by the cooling oil supply unit 3100.

  FIG. 2 shows an enlarged view of a cross section of the stator core 2000. As shown in FIG. 2, the stator core 2000 is configured by laminating a number of electromagnetic steel plates 2100 described later. Inside, a cooling oil passage 2102 is provided so that the slot around which the stator coil 2012 is wound and the outer peripheral surface of the stator core 2000 communicate with each other. The cooling oil passage 2102 is provided in a direction perpendicular to the rotation shaft 1000. Although only one cooling oil passage 2102 shown in FIG. 2 is described, a large number (at least corresponding to the number of slots) is provided.

  FIG. 3 shows a perspective view of the stator core 2000. In this figure, the thickness of the electrical steel sheet 2100 is shown in a large ratio with respect to its radial dimension (that is, the actual electrical steel sheet 2100 is compared with the size in the radial direction in FIG. Thinner than shown).

  As shown in FIG. 3, a hollow cylindrical stator core 2000 is constructed by laminating a number of hollow disk-shaped electromagnetic steel plates 2100. The electromagnetic steel plate 2100 is provided with a slot 2110 around which the stator coil 2012 is wound, and a cooling oil passage 2102 that connects the slot 2110 and the outer peripheral surface of the stator core 2000 is provided. The perspective view shown in FIG. 3 shows an example of the arrangement of the cooling oil passage 2102. As shown in FIG. 3, a cooling oil passage 2102 is provided at a predetermined position in a plurality of electromagnetic steel plates 2100, and they are stacked to constitute a stator core 2000. In this case, the arrangement of the cooling oil passage 2102 is determined so as not to affect the magnetic path formation generated in the stator core 2000 when a current is passed through the stator coil 2012.

  FIG. 4 shows a front view of the electromagnetic steel plate 2100. As shown in FIG. 4, in the electromagnetic steel plate 2100, a large number of slots 2110 and teeth 2120 are alternately formed, and the slot 2110 and the outer peripheral surface of the electromagnetic steel plate 2100 communicate with one of the numerous slots 2110. A cooling oil passage 2102 is provided.

  Note that the numbers and shapes of the slots 2110 and the teeth 2120 in the electromagnetic steel sheet shown in FIGS. 3 and 4 are examples, and the present invention is not limited to such an electromagnetic steel sheet 2100.

  FIG. 5 shows an enlarged view of a part of FIG. As shown in FIG. 5, insulating paper 2112 is provided in the slot 2110 of the electromagnetic steel plate 2100. The cooling oil supplied from the outer peripheral surface of the stator core 2000 via the cooling oil passage 2102 is supplied from the insulating paper 2112 to the gap between the copper wires constituting the stator coil 2012 wound inside the slot 2110.

  FIG. 6 is an enlarged view of a part of FIG. As shown in FIG. 6, the slot 2110 is provided with a number of copper wires 2130 that form the stator coil 2012 so as to be included in the insulating paper 2112. The slot 2110 includes a large number of copper wires 2130 and air gaps (air layers) between the copper wires 2130. At the time of manufacture, the stator coil 2012 is assembled in the slot 2110 and then varnished and fixed. Further, a wedge 2150 having a certain length in the direction of the rotating shaft 1000 is provided so that the stator coil 2012 assembled in the slot 2110 does not protrude from the slot 2110.

  As shown in FIG. 6, the cooling oil is supplied to the gap between the copper wires 2130 via the cooling oil passage 2102, the cooling oil comes into contact with the copper wires 2130, and between the copper wire 2130 and the cooling oil. Heat exchange is performed and Joule heat generated in the copper wire is taken away by the cooling oil, so that heat generation by Joule heat is suppressed.

  Through the cooling oil passage 2102 formed in this way, the cooling oil supplied from the cooling oil supply unit 3100 is guided to the gap 2140 between the copper wires 2130 of the slots 2110 of the stator core 2000, and the copper wire 2130 (stator coil 2012). Is cooled.

  In the electric motor having the above-described structure, it will be described that Joule heat generated in the copper wire 2130 in the slot 2110 is cooled by passing a current through the stator coil 2012 of the stator core 2000.

  In order for the electric motor to rotate about the rotation shaft 1000 and drive the vehicle, a predetermined current (for example, a current for generating a torque required for running the vehicle) is generated in the coil of the stator core 2000. Will be washed away. At this time, the stator coil 2012 of the stator core 2000 generates heat due to this current. Specifically, a large number of copper wires 2130 constituting the stator coil 2012 generate heat due to Joule heat.

  ATF, which is cooling oil, is supplied from the cooling oil supply unit 3100 to the inside of the stator core 2000 from the inlet of the cooling oil passage 2102 provided on the outer periphery of the stator core 2000. Since the cooling oil passage 2102 of the stator core 2000 communicates with the outer peripheral side of the slot 2110, the cooling oil penetrates into the slot 2110. The cooling oil penetrates into the gap 2140 between the copper wires 2130 constituting the stator coil 2102 wound inside the slot 2110, and the Joule heat generated in the copper wire 2130 is cooled by the cooling oil.

  As described above, in the electric motor according to the present embodiment, the cooling oil passage communicating with the outer peripheral side of the stator core is provided in the slot of the stator core. Cooling oil such as ATF is supplied to the cooling oil passage from the cooling oil supply unit. The ATF penetrates into the slot through the cooling oil passage, and the ATF penetrates into the gap between the copper wire and the copper wire constituting the stator coil wound around the slot. Heat exchange is performed between them, and Joule heat generated in the copper wire is cooled by the cooling oil. As a result, in a rotating electrical machine that supplies cooling oil to the stator from the outside of the stator, the stator can be efficiently cooled with a simple structure.

  In the above-described embodiment, the stator core has a structure in which a large number of electromagnetic steel sheets are laminated. The present invention is limited to a stator core formed by laminating such a large number of electromagnetic steel sheets. Is not to be done.

<Second Embodiment>
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. The electric motor according to the second embodiment described below is mounted on a vehicle and has a feature in the cooling structure of the stator portion, as in the first embodiment described above. In the electric motor according to the above-described embodiment, a cooling oil passage communicating with the outer peripheral side of the stator core is provided in a slot of the stator core, and cooling oil such as ATF is supplied to the stator coil to improve cooling efficiency. In the electric motor according to the present embodiment, a plurality of electromagnetic steel plates are laminated to form a stator core, a spacer that can be welded is inserted between the electromagnetic steel plates, a gap is provided between the electromagnetic steel plates, and ATF or the like is provided. Cooling oil was supplied to the stator coil to increase cooling efficiency. In the following description, parts having the same configurations as those of the electric motor according to the present embodiment and the electric motor according to the first embodiment described above are denoted by the same reference numerals. Its structure and function are the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 7, the electric motor mounted in the vehicle which concerns on the 2nd Embodiment of this invention is demonstrated. As shown in FIG. 7, the vehicle is mounted with the rotating shaft horizontal or substantially horizontal. FIG. 7 shows a cross-sectional view of such an electric motor.

  As shown in FIG. 7, the electric motor has a stator portion formed by laminating a plurality of electromagnetic steel plates. In this laminated portion, one spacer is provided for each predetermined number of electromagnetic steel sheets, and a gap for supplying cooling oil is formed between the electromagnetic steel sheets. In the following description, spacers are inserted into three locations of the stator core 4000 to make the stator core 4000 into four partial stators (first stator 4010, second stator 4020, third stator 4030, and fourth stator 4040). At this time, as shown in FIG. 7, three gaps 4100 (a first gap 4110, a second gap 4120, and a third gap 4130) are formed.

  A cooling oil (for example, ATF) can be permeated into the gap 4100 to cool the stator coil. That is, the copper loss generated in the stator coil is cooled by the cooling oil. Part of the heat generated by the copper loss is transferred to the stator core 4000 and radiated from the housing 3000 to the outside of the electric motor.

  FIG. 8 shows a perspective view of the stator core 4000. In this figure, as in the first embodiment, the thickness of the electromagnetic steel sheet 2100 is shown in a large ratio with respect to its radial dimension.

  As shown in FIG. 8, a hollow cylindrical stator core 4000 is configured by laminating a number of hollow disk-shaped electromagnetic steel plates 2100. Spacers 4210, 4220, 4230 are provided for each predetermined number of electromagnetic steel plates 2100, and gaps 4100 ((first gap 4110, second gap 4120, third gap 4130) are formed between the electromagnetic steel plates 2100. The spacers 4210, 4220, and 4230 are provided so as to be symmetrical (for example, at intervals of 60 degrees) in the cross section of the stator core 4000. Therefore, for example, the spacer 4210 is provided along the circumferential direction of the spacer 4210. In addition, a spacer 4211, a spacer 4212, a spacer 4213, a spacer 4214, and a spacer 4215 are provided.

  The spacer 4210, the spacer 4220, and the spacer 4230 are provided with a connecting member 4200 for fixing the spacers to the electromagnetic steel plate 2100. The spacer 4210, the spacer 4220, the spacer 4230, the electromagnetic steel plate 2100, and the connecting member 4200 are weldable members, and the stator core 4000 having a gap is integrated by welding.

  Note that the connecting member 4201 is provided to fix the spacer 4211, the spacer 4221, and the spacer 4231 that are hidden in the connecting member 4201 in the drawing to the electromagnetic steel plate 2100, and the connecting member 4202 is hidden in the connecting member 4202 in the drawing. The spacer 4212, the spacer 4222, and the spacer 4232 are provided to fix the electromagnetic steel plate 2100. Such connecting members are provided, for example, every 60 degrees. When such a gap is formed, the gap interval, the number, the size of the spacer, and the size of the connecting member are set so as not to affect the formation of the magnetic path generated in the stator core 4000 when a current is passed through the stator coil 2012. Is determined.

  FIG. 9 shows a cross section A of FIG. This section is a section that does not include the connecting member. As shown in FIG. 9, a first gap 4110 is provided by a first spacer 4210 between the first stator 4010 and the second stator 4020, and between the second stator 4020 and the third stator 4030, A second gap 4120 is provided by the second spacer 4220, and a third gap 4130 is provided by the third spacer 4230 between the third stator 4030 and the fourth stator 4040. The gap 4100 allows the cooling oil to penetrate to the stator coil 2012.

  FIG. 10 shows a cross section B of FIG. This cross section includes a connecting member. As shown in FIG. 10, a first spacer 4210 is provided between the first stator 4010 and the second stator 4020, and a second spacer 4220 is provided between the second stator 4020 and the third stator 4030. The third spacer 4230 is provided between the third stator 4030 and the fourth stator 4040. The first spacer 4210, the second spacer 4220, and the third spacer 4230 are connected to the connecting member 4200, the electromagnetic steel plate 2100, and the like. And an integrated stator 4000 is formed.

  FIG. 11 is a front view of the electromagnetic steel plate 2100, and FIG. 12 is a front view of the electromagnetic steel plate 2100 combined with the connecting member 4200 and the spacer 4210. Note that the numbers and shapes of the slots 2110 and the teeth 2120 in the electromagnetic steel sheet shown in FIGS. 11 and 12 are examples, and the present invention is not limited to such an electromagnetic steel sheet 2100.

  An electromagnetic steel plate 2100 shown in FIG. 11 is a normal electromagnetic steel plate, and the electromagnetic steel plate 2100 has a large number of slots 2110 and teeth 2120 formed alternately. FIG. 12 is a diagram in which spacers and connecting members are described together on the electromagnetic steel plate 2100 shown in FIG. As shown in FIG. 12, the spacer and the connecting member are provided at six locations every about 60 degrees. The position and number are not limited.

  FIG. 12 shows the arrangement of spacers and connecting members provided between the first stator 4010 and the second stator 4020 in order to form the first gap 4110. The first spacer 4210, the second spacer 4211, the third spacer 4212, the fourth spacer 4213, the fifth spacer 4214, and the sixth spacer 4215 are respectively the first connecting member 4200, the second connecting member 4201, the third spacer. In the same phase, the connecting member 4202, the fourth connecting member 4203, the fifth connecting member 4204, and the sixth connecting member 4205 join the spacer for forming another gap and the electromagnetic steel plate 2100 by welding.

  In the electric motor having the above-described structure, it will be described that Joule heat generated in the copper wire 2130 in the slot 2110 is cooled by passing a current through the stator coil 2012 of the stator core 4000.

  In order for the electric motor to rotate about the rotation shaft 1000 and drive the vehicle, a predetermined current (for example, a current for generating a torque required to drive the vehicle) is generated in the coil of the stator core 4000. Will be washed away. At this time, the stator coil 2012 of the stator core 4000 generates heat due to this current. Specifically, a large number of copper wires 2130 constituting the stator coil 2012 generate heat due to Joule heat.

  ATF, which is cooling oil, is supplied into the stator core 4000 from the inlet of the outer periphery of the stator core 4000 in the gap 4100. Since the gap 4100 of the stator core 4000 communicates with the stator coil 2012, the cooling oil cools the stator coil 2012. The cooling oil cools Joule heat generated in the copper wire 2130.

  As described above, in the electric motor according to the present embodiment, a gap having a predetermined interval is provided for each predetermined number of electromagnetic steel sheets forming the stator core. Cooling oil such as ATF is supplied to this gap. The ATF reaches the stator coil through this gap, heat exchange is performed between the copper wire constituting the stator coil and the cooling oil, and Joule heat generated in the copper wire is cooled by the cooling oil. As a result, in a rotating electrical machine that supplies cooling oil to the stator from the outside of the stator, the stator can be efficiently cooled with a simple structure.

  In the above-described embodiment, the stator core has a structure in which a large number of electromagnetic steel sheets are laminated. The present invention is limited to a stator core formed by laminating such a large number of electromagnetic steel sheets. Is not to be done. That is, the first stator core 4010, the second stator core 4020, the third stator core 4030, and the fourth stator core 4040 may be configured integrally.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing of the electric motor which concerns on the 1st Embodiment of this invention. It is an enlarged view of the stator part which concerns on the 1st Embodiment of this invention. It is a perspective view of the stator part which concerns on the 1st Embodiment of this invention. It is a front view of the electromagnetic steel plate which concerns on the 1st Embodiment of this invention. It is the elements on larger scale of FIG. It is the elements on larger scale of FIG. It is sectional drawing of the electric motor which concerns on the 2nd Embodiment of this invention. It is a perspective view of the stator part which concerns on the 2nd Embodiment of this invention. It is an enlarged view of the stator part in the A cross section of FIG. It is an enlarged view of the stator part in the B cross section of FIG. It is a front view of the electromagnetic steel plate which concerns on the 2nd Embodiment of this invention. It is a front view of the electrical steel sheet which added the spacer and connecting member which comprise the gap which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  1000 Rotating shaft, 1010 Rotor, 1020 Bearing, 2000 Stator core, 2010 Stator coil end, 2012 Stator coil, 2100 Electrical steel plate, 2102 Cooling oil passage, 2110 Slot, 2112 Insulating paper, 2120 Teeth, 2130 Copper wire, 2140 Air gap, 2150 Wedge 3000 Housing, 3100 Cooling oil supply unit, 4000 Stator core, 4010 First stator, 4020 Second stator, 4030 Third stator, 4040 Fourth stator, 4100 gap, 4110 First gap, 4120 Second gap, 4130 Third gap 4200 1st connection member 4202 2nd connection member 4202 3rd connection member 4203 4th connection member 4204 5th connection member 4205 6th connection member 210,4220,4230 first spacer, 4211 second spacers, 4212 third spacers, 4213 fourth spacers 4214 Fifth spacer, 4215 sixth spacers.

Claims (12)

A rotation composed of a hollow cylindrical stator in which a plurality of slots and teeth are alternately formed, and a coil is mounted in the slot, and a rotatable rotor disposed on the inner peripheral side of the hollow portion of the stator. A stator cooling structure in an electric machine,
The cooling structure which provided the communicating hole which connects the said slot and the outer peripheral surface of the said stator in the stator core. The stator core is configured by laminating a number of thin steel plates having a hollow disk shape,
Each of the steel plates is formed with a plurality of slots and teeth alternately,
In each said steel plate, the said communicating hole is formed in the at least 1 slot of these slots by the notch part which connected the outer peripheral part of the said slot, and the outer peripheral part of the said steel plate. Cooling structure.   The notch part formed in each said steel plate is a cooling structure of Claim 2 formed so that the magnetic flux which generate | occur | produces with the electric current which flows into a stator coil may not be affected.   The cooling medium is communicated from the outer peripheral side to the inner peripheral side of the stator core through the communication hole, and the cooling medium is permeated into the gaps of the wire forming the stator coil in the slot. The cooling structure as described in. A rotation composed of a hollow cylindrical stator in which a plurality of slots and teeth are alternately formed, and a coil is mounted in the slot, and a rotatable rotor disposed on the inner peripheral side of the hollow portion of the stator. A stator cooling structure in an electric machine,
The cooling structure which provided the communication space which connects the said coil and the outer peripheral surface of the said stator core in the said stator core. The communication space is a gap between the thin steel plates,
The stator core is configured by laminating a number of thin steel plates having a hollow disk shape,
The cooling structure according to claim 5, wherein a spacer for providing the gap between the thin steel plates is provided between the thin steel plates for each predetermined number of the thin steel plates.   The cooling structure according to claim 6, wherein the spacer is provided between the thin steel plates so as to be symmetrical with respect to a cross-sectional shape of the stator core. A plurality of the communication spaces are provided,
At least two spacers are provided in the cross section of the stator core, and the spacers are provided in the cross section of the stator core so that the rotation axis center of the rotating electrical machine is the center of the point object,
The cooling structure according to claim 7, further comprising a connecting member that connects spacers that form the same communication space at the same angle in a point object.   The cooling structure according to claim 8, wherein the spacer, the connecting member, and the thin steel plate are joined by welding.   The cooling structure according to claim 5, wherein a cooling medium is communicated from the outer peripheral side to the inner peripheral side of the stator core through the communication space to cool the stator coil in the slot.   The cooling structure according to claim 4 or 10, wherein the cooling medium is cooling oil.   The cooling structure according to claim 11, wherein the cooling oil is an automatic transmission fluid.

Images