JP2012090411A - Cooling structure of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate work to connect coolant supply pipes to two coolant supply ports of two coolant chambers which are formed by covering coil end portions on both axial sides.SOLUTION: A cooling structure 10 of a rotary electric machine, which cools a coil end portion 24 with a coolant in a stator 12 including a stator core 14 and a coil 16, includes a lead side cover member 28a covering a lead side coil end portion 24a and forming a first cooling oil chamber 26a, a lead opposite side cover member 28b covering a lead opposite side coil end portion 24b and forming a second cooling oil chamber 26b, a coolant supply pipe 60 connecting to a first and second cooling oil supply ports 38a, 38b for supplying cooling oil to the first and second cooling oil chambers 26a, 26b. The first and second cooling oil supply ports 38a, 38b are separately formed on the lead side cover member 28a so as to face in the same direction.

Description

  The present invention relates to a rotating electrical machine cooling structure, and more particularly to a rotating electrical machine cooling structure that cools a coil end portion of a stator coil with a coolant.

  2. Description of the Related Art Conventionally, there has been known a rotating electrical machine including a stator in which a plurality of stator coils (hereinafter referred to simply as coils) are arranged in the circumferential direction on the inner peripheral portion of a cylindrical stator core. The coil is wound around a tooth portion projecting radially inwardly on the inner peripheral portion of the stator core, and both ends of the coil project outward at both ends in the axial direction of the stator. It constitutes the end part.

  The coil is connected to a lead wire, and a current flows through the coil when a voltage is applied from the outside through the lead wire. At this time, a so-called copper loss due to electrical resistance occurs inside a conductive element wire such as an insulation-coated copper wire constituting the coil, and the coil generates heat. When the coil temperature rises due to this heat generation, the insulation performance of the coil decreases. When the rotating electrical machine is a multiphase AC motor, discharge tends to occur particularly between the coil end portions of the different phase coils where the potential difference becomes large. In order to prevent such discharge, the coil end portion of the coil is cooled by a coolant such as cooling oil.

  JP-A-2006-271150 (Patent Document 1) is a related art document related to this. Patent Document 1 discloses a motor generator cooling structure. In this cooling structure, the coil end portion that protrudes outward in a ring shape on the end surface in the axial direction of the stator core is liquid-tightly covered with a cooling jacket, and the jacket is filled with cooling oil, thereby supplying the coil end. It is described that the coil is cooled by bringing the part into contact with the cooling oil in the entire circumferential direction. In this cooling structure, the stator is housed in a cylindrical case, and side plates are attached to both sides of the case in the axial direction. An oil supply port is formed in the side plate and the cooling jacket, and the oil supply ports are provided on both sides in the axial direction corresponding to the coil end portions at both ends in the axial direction.

JP 2006-271150 A

  In the cooling structure of Patent Document 1, oil supply ports are provided in cooling jackets provided on both axial sides of the stator, and cooling oil is supplied from the respective oil supply ports to the coil end portions on both axial sides. is there. And these two oil supply ports are each formed as an opening toward the opposite side in the axial direction. Therefore, if the motor generator incorporating this cooling structure is used as a driving power source and an attempt is made to connect the oil supply pipe to the oil supply port formed in the opposite direction as described above when the transmission is assembled, The pipe connection work may be difficult due to the relationship between the assembly posture, the assembly space, the work space, and the like.

  An object of the present invention is to connect a coolant supply pipe to two coolant supply ports for supplying coolant to two coolant chambers formed on both sides in the axial direction so as to cover the coil end portion in an annular shape. It is an object of the present invention to provide a cooling structure for a rotating electrical machine that can easily perform the work to be performed.

  A cooling structure for a rotating electrical machine according to the present invention includes a coil end portion that protrudes outward from both end faces of the stator core in the stator axial direction in a stator including a cylindrical stator core and a plurality of coils wound in the circumferential direction of the stator core. A cooling structure for a rotating electrical machine that cools with a cooling liquid, the lead side forming a first cooling liquid chamber that covers a lead side coil end portion to which a lead wire for supplying power to the coil is connected and accommodates the cooling liquid therein An anti-lead-side cover member that covers the cover member and the anti-lead-side coil end portion that is positioned opposite to the axial direction with respect to the lead-side coil end portion to form a second cooling liquid chamber that contains the cooling liquid therein And a cooling connected to a first cooling liquid supply port for supplying a cooling liquid to the first cooling liquid chamber and a second cooling liquid supply port for supplying a cooling liquid to the second cooling liquid chamber. It includes a supply pipe, the said first and second coolant supply port are formed separately in the same direction in at least one of the cover member.

  In the rotating electrical machine cooling structure according to the present invention, the coolant supply pipe is a branch pipe that discharges the coolant received from one end portion from two other end portions, and the two other end portions are the first end portions. The first and second coolant supply ports may be inserted from one direction and connected to the cover member.

  Moreover, in the cooling structure for a rotating electrical machine according to the present invention, the first and second coolant supply ports may be formed so as to open to an axial end surface of the lead side cover member.

  In the rotating electrical machine cooling structure according to the present invention, the first coolant supply port and the second coolant supply may be used to adjust the amount of coolant supplied to each of the first and second coolant chambers. The opening diameter may be different depending on the opening, or the inner diameter of the cooling liquid supply pipe connected to each of the cooling liquid supply ports may be different.

  Furthermore, in the cooling structure for a rotating electrical machine according to the present invention, the coolant entrance path to the first and second coolant chambers is substantially directed in an oblique direction that is not orthogonal to the radially outer peripheral surface of the coil end portion. It may be formed in a V shape.

  In the rotating electrical machine cooling structure according to the present invention, the first coolant supply port for supplying the coolant to the first coolant chamber on the lead side and the second coolant for supplying the coolant to the second coolant chamber on the non-lead side are provided. Two coolant supply ports are formed separately in at least one cover member in the same direction. For this reason, the operation | work which connects a coolant supply pipe | tube to a 1st and 2nd coolant supply port can be easily performed from one direction, confirming the sealing state of a connection part.

It is a perspective view of the stator provided with the cooling structure which is one embodiment of the present invention. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. FIG. 2 is an enlarged cross-sectional view of the cooling oil supply pipe in FIG. It is an expanded sectional view similar to FIG. 4A which shows another example of a cooling oil supply pipe. It is the DD sectional view taken on the line in FIG. It is a figure which shows another aspect regarding the connection of a 2nd cooling oil supply path. It is a figure which shows another aspect regarding the connection of a 2nd cooling oil supply path. It is the EE sectional view taken on the line in FIG. It is an enlarged view which shows the sealing state of the slot inner peripheral opening part of a stator. It is a figure which shows the sealing member inserted in a slot inner peripheral opening part. It is a figure which shows the modification by which the cooling oil supply pipe | tube was connected to the 1st and 2nd cooling oil supply port formed separately in each cover member.

  Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the application, purpose, specification, and the like.

  In the following description, the cooling liquid used in the cooling structure for a rotating electrical machine according to the present embodiment is described as cooling oil or cooling oil, but the cooling liquid in the cooling structure in the present invention is limited to this. Instead, other cooling liquids such as cooling water (eg, LLC) may be used.

  FIG. 1 is a perspective view showing a cooling structure 10 for a rotating electrical machine according to this embodiment assembled to a stator 12 for a rotating electrical machine, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. It is BB sectional drawing in FIG. Here, in FIG. 1, the axis X is the central axis of the stator and the stator core formed in a cylindrical shape, the direction along the central axis X is the axial direction, the direction orthogonal to the central axis X is the radial direction, and the central axis X A direction along the circumference of a circle drawn on the orthogonal plane centering on an upper point is called a circumferential direction. 2 and 3, the axial section on one radial side in the circumferential direction of the cylindrical stator 12, that is, the vertical when the rotating electric machine is mounted on the vehicle so that the central axis X is along the horizontal direction. Only the axial section of the lower half of the direction is shown.

  As shown in FIG. 1, the stator 12 includes a cylindrical stator core 14 and a coil 16 provided on the inner periphery of the stator core 14. The stator core 14 is configured by stacking and caulking a plurality of electromagnetic steel plates such as silicon steel plates that have been punched into a ring shape, and connecting them together by a technique such as welding, adhesion, or clamping. An IPM type rotor (not shown) is rotatably provided in the stator 12, and the rotor is driven to rotate by a rotating magnetic field electrically formed in the stator 12.

  A plurality of teeth portions 18 (see FIGS. 9 and 10) are formed on the inner peripheral portion of the stator core 14. The teeth portions 18 are arranged at predetermined intervals in the radial direction and project inward in the radial direction. The teeth portions 18 have the same axial length as the stator core 14 and are extended in the axial direction. Between the tooth portions 18 adjacent in the radial direction, the same number of slots 20 as the tooth portions 18 are formed. As will be described later, a part of the coil 16 is accommodated in the slot 20 which is a space portion.

  The coil 16 is configured by winding a conductive element wire such as an enameled copper wire around the teeth portion 18. The winding method of the coil 16 may be concentrated winding or distributed winding. Further, the conductive wire constituting the coil 16 may have a circular cross section or a rectangular cross section. Furthermore, the coil 16 may be mounted by being fitted with a tooth part 18 from the inside in the radial direction by being wound using a jig or the like, or by using a winding machine. The coil 16 may be formed while winding a conductive wire around the periphery, or, for example, a segment conductor formed in a U shape by bending a relatively rigid square wire having a rectangular cross section is slotted from one end in the axial direction. 20 are inserted in a state in which a plurality of them are arranged in the radial direction and straddling the teeth portion 18, and one of the two leg portions of the segment conductor protruding from the opening on the other side in the axial direction of the slot 20 is separated from the adjacent one in the radial direction. The coil 16 may be configured by connecting to the other of the two leg portions of the segment conductor.

  The coil 16 includes a slot portion 22 positioned in the slot 20 of the stator core 14 and coil end portions 24a and 24b formed to protrude axially outward from both axial end surfaces 13a and 13b of the stator core 14, respectively. ing. The coil end portions 24a and 24b have a generally annular shape on the end surfaces 13a and 13b of the stator core 14 when the stator 12 is viewed from the axial direction.

  As shown in FIG. 1, lead wires 2 u, 2 v, 2 w are electrically connected to one coil end portion 24 of the coil 16 of the stator 12. The lead wires 2u, 2v, 2w are for applying a voltage to the coil 16 from the outside. If the stator 12 is used in, for example, a three-phase AC rotating electric machine, the plurality of coils 16 are divided into U-phase, V-phase, and W-phase coil groups, and three lead wires 2u, 2v, 2w The phase coil group is connected to one end of the phase coil group, and the other end of each phase coil is electrically connected to each other at a neutral point. Hereinafter, the coil end portion 24a to which the lead wires 2u, 2v, 2w are connected is referred to as a lead side coil end portion, and the other coil end portion 24b located on the opposite side in the axial direction is referred to as an anti-lead side coil end portion.

  The cooling structure 10 for a rotating electrical machine according to the present embodiment includes a lead side cover member 28a that covers the lead side coil end portion 24a and forms a first cooling oil chamber 26a in a liquid-tight manner therein, and an anti-lead side coil end portion 24b. And an anti-lead-side cover member 28b that forms a second cooling oil chamber 26b therein, and a cooling oil supply pipe 60 that will be described in detail later. Hereinafter, the two cover members are collectively referred to as a cover member 28. The same applies to reference numerals indicating other elements.

  The cover member 28 can be suitably formed by, for example, a metal casting or a combination such as drawing of a metal plate or welding of a metal tube. The cover member 28 is formed as an annular member having a substantially U-shaped or L-shaped cross section so as to cover the coil end portions 24a and 24b over the entire circumference. Furthermore, the cover member 28 is fixed on the end surfaces 13a and 13b of the stator core 14 via a seal member such as a rubber packing. As a result, the cooling oil is prevented from leaking from the first and second cooling oil chambers 26 and 26b on the end faces 13a and 13b of the stator core 14.

  Referring to FIG. 1, three tabs 30 (only two are shown in FIG. 1) 30 project radially outward at equal positions in the circumferential direction at the edge of the cover member 28 in the axial direction. Each tab 30 is formed with a bolt insertion hole 32 therethrough. On the other hand, on the outer peripheral surface of the stator core 14, a bolt insertion portion 34 is bulged and formed at a position corresponding to the tab 30, and a bolt insertion hole (not shown) is formed through the inside in the axial direction. ing. As a result, the stator 12 and the cover member 28 are assembled in the state shown in FIG. 1, and the bolt insertion part 34 of the stator core 14 and the two tabs 30 above and below it are inserted through the bolts and tightened with nuts. The cover member 28 is fixed to the stator 12 in a liquid-tight state.

  A long bolt is inserted into the tab 30 and the bolt insertion portion 34, and the tip of the bolt is screwed into a female screw hole formed in the inner wall surface of a case (not shown) in which the rotating electrical machine is housed. The stator 12 may be fixed in the case together with the assembly of the cover members 28a and 28b to the stator core 14 by tightening.

  An opening 29 for passing the lead wires 2u, 2v, 2w is formed on the outer circumferential surface of the lead side cover member 28 in the radial direction. The work of electrically connecting the lead wires 2u, 2v, 2w to the lead-side coil end portion 24a may be performed before the lead-side cover member 28a is attached to the stator 12, or the opening 29 is attached after the cover member 28a is attached. You may go through.

  The opening 29 of the lead-side cover member 28a is blocked by a seal member (not shown) for ensuring a liquid-tight state while passing through the lead wires 2u, 2v, 2w, or as described in detail later. You may use as a cooling oil discharge port which discharges the cooling oil supplied to the 1st cooling oil chamber 26a.

  Referring to FIGS. 1 and 2, a first supply path forming portion 36a bulging radially outward is formed on the outer peripheral portion of the lead side cover member 28a so as to extend in the axial direction. The first supply path forming portion 36a is formed to be longer in the axial direction than the portion of the lead-side cover member 28a that forms the first cooling oil chamber 26a, and is in contact with the stator 12 or with a gap therebetween. Extends to the center position in the axial direction of the outer peripheral surface. However, as will be described later, only the first cooling oil supply passage for supplying the cooling oil to the first cooling oil chamber 26a is formed in the first supply passage forming portion 36a, so the first cooling oil chamber 26a is formed. In this case, it is not necessary to provide a bulging portion corresponding to the first supply path forming portion 36a in the non-lead-side cover member 28b.

  A first cooling oil supply port 38a is formed on the axial end surface of the first supply path forming portion 36a, that is, the axial end surface of the lead side cover member 28a. A first cooling oil supply path 40a that connects the first cooling oil chamber 26a and the first cooling oil supply port 38 is formed in the first supply path forming portion 36a.

  Referring to FIGS. 1 and 3, the lead-side second supply that bulges outward in the radial direction at a predetermined distance in the circumferential direction from the first supply path forming portion 36a is provided on the outer periphery of the lead-side cover member 28a. The path forming part 36c is formed by extending in the axial direction. The second supply path forming portion 36c is formed longer in the axial direction than the portion of the lead-side cover member 28a that forms the first cooling oil chamber 26a, and is in contact with the stator 12 or with a gap therebetween. Extends to the center position in the axial direction of the outer peripheral surface.

  Further, an anti-lead-side second supply path forming portion 36b that bulges radially outward is also formed on the outer periphery of the anti-lead-side cover member 28b so as to extend in the axial direction. The anti-lead-side second supply path forming portion 36b is formed longer in the axial direction than the portion of the anti-lead-side cover member 28b that forms the second cooling oil chamber 26b, and is in contact with the stator 12 or has a gap. It extends to the axial center position of the outer peripheral surface of the stator core 14.

  The non-lead-side second supply path forming portion 36b is connected to the lead-side second supply path forming portion 36c of the lead-side cover member 28a so as to form one protrusion when the cooling structure 10 is assembled to the stator 12. It is configured. That is, the axial end portion (the lower end portion in FIG. 1, the left end portion in FIG. 3) 37a of the lead side second supply path forming portion 36c and the anti-lead side second supply path forming portion (the upper end portion in FIG. 1). 2 and the right end portion 37b in FIG. 2 are connected to each other on the outer peripheral surface of the stator core 14 by pressure contact with each other, whereby the second supply path forming section 36 is formed by the two second supply path forming sections 36b and 36c. It is configured.

  In the 2nd supply path formation part 36, the 2nd cooling oil supply path 40b connected to the 2nd cooling oil chamber 26b is extended | stretched and formed along the axial direction. The second cooling oil supply path 40b is configured by connecting a lead-side second supply path portion 42a and an anti-lead-side second supply path portion 42b. The connecting portion is sealed by an appropriate sealing member 44 such as an O-ring. Thereby, the cooling oil leak from a connection part is prevented reliably.

  The second cooling oil supply path 40b is formed on the axial end face of the lead side second supply path forming portion 36c, that is, on the axial end face of the lead side cover member 28a in which the first cooling oil supply port 38a is opened. Has been. This opening serves as a second cooling oil supply port 38b for supplying cooling oil to the second cooling oil chamber 26b. In other words, the first cooling oil supply port 38a and the second cooling oil supply port 38b are formed separately in the same direction on the lead side cover member 28a.

  In the present embodiment, an example in which the first and second cooling oil supply ports 38a and 38b are formed in the lead side cover member 28a will be described, but the present invention is not limited to this, and both supply ports are anti-lead. It may be formed on the side cover member 28b.

  As shown in FIG. 1, a cooling oil supply pipe 60 is connected to the first and second cooling oil supply ports 38a and 38b formed in the lead side cover member 28a. The cooling oil supply pipe 60 is a branch pipe formed in a lower case “h” shape as shown in FIG. 4A, and discharges the cooling oil received from one end 62 from the two other ends 64a and 64b. It is configured. The one other end 64a is connected to the first coolant supply port 38a by press fitting or the like, and the other other end 64b is connected to the second coolant supply port 38b by press fitting or the like. Each connecting portion is sealed by an appropriate sealing member 66 such as an O-ring, for example, so that the cooling oil supply port 38 and the cooling oil supply pipe 60 are connected in a liquid-tight state to prevent the cooling oil from leaking. It can be surely prevented.

  Here, the inner diameter d1 of one other end 64a connected to the first cooling oil supply port 38a is different from d2 of the other other end 64b connected to the second cooling oil supply port 38b. Also good. Specifically, the inner diameter d2 may be formed smaller than the inner diameter d1. By doing in this way, the amount of cooling oil supplied to the 1st and 2nd cooling oil chambers 26a and 26b can be adjusted as desired. For example, when the lead-side coil end portion 24a is formed larger than the anti-lead-side coil end portion 24b, the one other end is used as described above in order to relatively increase the cooling performance of the lead-side coil end portion 24a. The cooling oil supply amount to the first cooling oil chamber 26a may be increased by forming the inner diameter d1 of the portion 64a to be relatively large.

  The same thing as this may be carried out for at least one of the first and second cooling oil supply ports 38a, 38b and the first and second cooling oil supply paths 40a, 40b. That is, the opening diameters of the first and second cooling oil supply ports 38a and 38b may be made different, or the flow passage cross sections are made different for at least a part of the first and second cooling oil supply passages 40a and 40b. Also good. These may be implemented instead of or in combination with the pipe inner diameter of the cooling oil supply pipe 60 being different.

  In the present embodiment, the cooling oil supply pipe 60 having a lowercase letter “h” is used. However, the present invention is not limited to this. For example, as shown in FIG. 4B, a cooling oil supply pipe formed of a substantially Y-shaped branch pipe may be used. With such a shape, the cooling oil received from the one end 62 can be evenly branched and flowed to the two other end portions 64a and 64b, and the same as the first and second cooling oil chambers 26a and 26b. Effective for supplying a quantity of cooling oil. In the above description, the cooling oil supply pipe 60 is a branch pipe. However, the present invention is not limited to this, and individual cooling oil supply pipes may be connected to the first and second cooling oil supply ports 38a and 38b. Good. In this case, the amount of cooling oil supplied for each individual cooling oil supply pipe may be adjusted.

  FIG. 5 is a cross-sectional view taken along line DD in FIG. The first cooling oil supply path 40a is substantially V-shaped toward the oblique direction in which the cooling oil entry path to the first cooling oil chamber 26a is not orthogonal to the outer peripheral surface of the lead side coil end portion 24a in the radial direction. It includes two branch channels 41 and 41 that expand. Thereby, the cooling oil fed into the first cooling oil chamber 26a from the branch flow path 41 of the first cooling oil supply path 40a flows with low resistance along the outer peripheral surface on the radially outer side of the lead side coil end portion 24a. The cooling oil can be smoothly supplied to the first cooling oil chamber 26a. Since the same applies to the second cooling oil supply passage 40b for supplying the cooling oil to the second cooling oil chamber 26b, illustration and description thereof are omitted.

  6 and 7 show a modification of the connecting portion between the lead-side second supply path portion 42a and the anti-lead-side second supply path portion 42b. In the modification shown in FIG. 6, the end 37b of the second supply path forming portion 36b of the non-lead-side cover member 28b is formed thin, while the end 37a of the second supply path forming portion 36c of the lead-side cover member 28a. A recess 37c is formed inside. The concave portion 37c is formed to have an inner diameter and an axial length that allow the narrowed end portion 37b of the anti-lead-side supply path forming portion 36b to be fitted by press-fitting. Then, the fitting and connecting portions are sealed by an appropriate seal member 44 such as an O-ring. As described above, the connecting portion between the lead-side second supply path portion 42a and the anti-lead-side second supply path portion 42b is fitted and connected by press-fitting and sealed by the seal member, so that the cooling oil leaks at the connecting portion. Can be prevented more reliably.

  In the modification shown in FIG. 7, the axial length is set shorter than that shown in FIG. 2 so that a gap is provided between the end portions 37a and 37b of the second supply path forming portions 36b and 36c. Both ends of the second supply path portion 42a and the non-lead-side second supply path portion 42b are connected by a hollow connection tube 46 press-fitted at both ends. An appropriate seal member 44 such as an O-ring is disposed on the outer periphery in the vicinity of both ends of the connection pipe 46 for sealing. By connecting with the connecting pipe 46 and sealing with the sealing member 44 in this way, leakage of the cooling oil in the connecting portion can be prevented more reliably, and the two second supply path forming portions 36b and 36c can be prevented. Since the errors in the circumferential position and the axial length can be absorbed by interposing the connecting pipe 46, the assembly of the cooling structure 10 is also improved.

  7 is a cross-sectional view taken along line EE in FIG. The cooling structure 10 of the present embodiment communicates the first cooling oil chamber 26a formed around the lead-side coil end portion 24a and the second cooling oil chamber 26b formed around the non-lead-side coil end portion 24b. The communication path 48 is provided. As shown in FIG. 1, the communication passage 48 is formed in a communication passage forming portion 50 that is formed to bulge radially outward at the outer peripheral portion of the cover member 28 and to extend in the axial direction.

  In the present embodiment, two communication path forming portions 50 are provided between the first and second supply path forming portions of the cover member 28 at intervals in the circumferential direction, and communicate with each other in the communication path forming portions 50. Each passage 48 is formed. By providing the communication path 48 at such a position, the communication path 48 is also arranged on the lower side in the vertical direction in the same manner as the cooling oil supply path 40 when the rotating electrical machine is installed so that the central axis X is along the horizontal direction. Can be done.

  The communication path 48 is formed by connecting a lead side communication path part 48a and an anti-lead side communication path part 48b. The connection between the ends of the lead side communication path forming portion 50a including the lead side communication path portion 48a and the anti-lead side communication path forming portion 50b including the anti-lead side communication path portion 48b is described with reference to FIGS. Since it is the same as that of the case of the 2nd supply path formation parts 36b and 36c demonstrated, description here is abbreviate | omitted by assistance.

  Thus, even if the supply pressure and / or supply amount of the cooling oil to each cooling oil chamber differ by making the 1st and 2nd cooling oil chambers 26a and 26b communicate with each other via the communication path 48, the communication path As the coolant flows through 48, the amount and pressure of the coolant oil are leveled between the coolant chambers. As a result, the same cooling performance can be secured and maintained for the lead side coil end portion 24a and the anti-lead side coil end portion 24b.

  Next, referring to FIGS. 9 and 10, the seal of the inner peripheral portion of the slot of the stator 12 will be described. FIG. 9 is an enlarged view showing a sealed state of the slot inner peripheral opening of the stator 12. FIG. 10 is a view showing a seal member inserted into the slot inner peripheral opening. In FIG. 10, the coil is not shown.

  As shown in FIG. 9, a slot 20 formed in the tooth portion 18 extends in the axial direction and opens in the inner peripheral portion of the stator core 14. In the slot 20, for example, a slot portion 22 of the coil 16 is accommodated while being surrounded by a sheet-like insulating member 52.

  The opening 21 on the radially inner side of the slot 20 is closed in a liquid-tight state by a seal member 54 made of, for example, a resin molded product. As shown in FIG. 10, the seal member 54 is inserted into the radial opening 21 of the slot 20 from the axial direction and fixed by a method such as adhesion. Further, the plurality of seal members 54 divided in the circumferential direction are attached to the entire inner periphery of the stator core 14, so that all the slot openings 21 are sealed. Here, the seal member 54 is attached to the slot opening 21 after the coil 16 is disposed in the slot 20. However, in the case of a segment type coil, the seal member 54 may be attached to the stator core 14 before the coil is attached. Good.

  Since the radial opening 21 of the slot 20 is sealed by the seal member 54 in this way, even if the cooling oil flows from at least one of the cooling oil chambers 26a and 26b into the gap of the coil slot portion in the slot 20, the stator As a result, the leaked cooling oil can be prevented from coming into contact with the rotor in the stator 12 and hindering rotation.

  In the present embodiment, the seal member is inserted into the slot opening portion from the axial direction and sealed, but the slot opening portion 21 may be sealed in any manner. For example, a coil may be wound around the tooth portion 18 and then put into the slot opening 21 to bury it, for example, to prevent oil leakage, or a thin adhesive sheet may be attached to the inner periphery of the stator core 14. The slot opening 21 may be closed, or a sealing member is provided between the cover member 28 and the stator core 14 so that the cooling oil does not flow into the slot 20 from the axial opening of the slot 20. May be.

  Subsequently, the operation of the rotating electrical machine including the cooling structure 10 having the above-described configuration will be described.

  When a three-phase AC voltage is applied to the stator coil 16 via the lead wires 2u, 2v, and 2w, the teeth portion 18 around which the coil 16 is wound is excited, thereby forming a rotating magnetic field in the stator 12. The And the rotor in the stator 12 is rotationally driven by this rotating magnetic field.

  When energized, the coil 16 generates heat and the temperature rises. If this is left as it is, the insulation performance is deteriorated, and in particular, discharge tends to occur between the different-phase coils in which the potential difference is large at the coil end portion 24. However, in the cooling structure 10 of the present embodiment, the cooling oil chamber 26 is formed so as to cover the entire circumference of the coil end portion 24, and the cooling oil supplied from the cooling oil supply port 38 is received in the cooling oil chamber 26. be satisfied. Therefore, the coil end portion 24 is efficiently cooled by being in contact with the cooling oil on all the inner and outer surfaces in the radial direction and on the entire side surface of the axial end surface. Therefore, in the rotating electrical machine provided with the cooling structure 10 of the present embodiment, the insulation performance of the coil 16 can be maintained or improved. As a result, the size of the rotating electrical machine can be reduced by increasing the current density flowing through the coil 16, and the coil Cost reduction can be achieved by eliminating the insulating paper sandwiched between the different-phase coils at the end.

  The cooling oil whose temperature has been increased by cooling the coil end portion 24 is discharged to the outside through, for example, the lead opening 29, and the temperature is lowered by dissipating heat through an oil cooler or the like, and the cooling oil is supplied by an oil pump. Circulation and supply to the port 38 will be performed.

  In the cooling structure 10 of the present embodiment, the first and second cooling oil supply ports 38a and 38b for supplying the cooling oil to the first and second cooling liquid chambers 26a and 26b are provided on the lead side on one axial side. Since the cover member 28a is formed in the same direction on the axial end face of the cover member 28a, an operation of connecting the cooling oil supply pipe 60 by assembling the rotating electrical machine incorporating the cooling structure 10 to the transmission as a driving power source. When performing, the connection work can be easily performed from one direction while confirming the sealing state of the connection part only by ensuring the work space only on the axial end surface side of the lead side cover member 28a.

  In addition, the cooling structure of the rotary electric machine which concerns on this invention is not limited to embodiment mentioned above, A various improvement and change are possible.

  In the above description, the first and second coolant supply ports 38a and 38b are formed on the end face in the axial direction of the lead side cover member 28a. However, the present invention is not limited to this. For example, the circumferential direction of the lead side cover member 28a An opening may be formed on the outer side wall. In this case, if the circumferential interval between the first and second cooling oil supply ports is not so large, it can be said that the first and second cooling oil supply ports face in the same direction. Is possible.

  Further, as shown in FIG. 11, the first cooling oil supply port 38a is formed in the circumferential outer wall of the lead side cover member 28a, while the second cooling oil supply port is formed in the circumferential outer wall of the non-lead side cover member 28b. 38b may be formed separately in the same direction. Here, the first and second cooling oil supply ports 38a and 38b may be aligned along the axial direction, or may be provided at positions that are not aligned in the axial direction. In any case, the two ends 64a and 64b of the cooling oil supply pipe 61 having a substantially F shape are inserted and connected to the first and second cooling oil supply ports 38a and 38b from below the stator 12 of the rotating electrical machine. And the same effects as described above can be obtained.

  2u, 2v, 2w Lead wire, 10 Cooling structure for rotating electrical machine, 12 Stator, 13a, 13b End face of stator core, 14 Stator core, 16 Stator coil or coil, 18 teeth, 20 slots, 21 Slot radial opening, 22 Coil slot Part, 24 coil end part, 24a lead side coil end part, 24b counter lead side coil end part, 26 cooling oil chamber, 26a first cooling oil chamber, 26b second cooling oil chamber, 28 cover member, 28a lead side cover member 28b Anti-lead side cover member, 29 Lead opening, 30 Tab, 32 Bolt insertion hole, 34 Bolt insertion part, 36a First supply path forming part, 36b Anti-lead side second supply path forming part, 36c Lead side second Supply path forming part, 37a, 37b end part, 37c recessed part, 38 Cooling oil Supply port, 38a 1st cooling oil supply port, 38b 2nd cooling oil supply port, 40a 1st cooling oil supply channel, 40b 2nd cooling oil supply channel, 41 branch channel, 42a Lead side 2nd supply channel part, 42b Lead side second supply path part, 44, 66 seal member, 46 connecting pipe, 48 communication path, 48a lead side communication path part, 48b anti-lead side communication path part, 50 path forming part, 50a lead side communication path forming part, 50b Anti-lead side communication path forming part, 52 Insulating member, 54 Seal member, 60, 61 Cooling oil supply pipe, 62 One end part, 64a, 64b The other end part, X Central axis.

Claims (5)

In a stator including a cylindrical stator core and a plurality of coils wound in the circumferential direction of the stator core, a cooling structure for a rotating electrical machine that cools coil end portions protruding outward from both end faces of the stator core in the stator axial direction with a coolant. There,
A lead-side cover member that forms a first coolant chamber that covers a lead-side coil end portion to which a lead wire that feeds power to the coil is connected and accommodates a coolant therein;
An anti-lead-side cover member that covers the anti-lead-side coil end portion located opposite to the lead-side coil end portion in the axial direction and forms a second cooling liquid chamber that contains cooling liquid therein;
A coolant supply pipe connected to a first coolant supply port for supplying coolant to the first coolant chamber and a second coolant supply port for supplying coolant to the second coolant chamber; With
The first and second coolant supply ports are formed separately in at least one cover member in the same direction,
Cooling structure for rotating electrical machines. The cooling structure for a rotating electrical machine according to claim 1,
The cooling liquid supply pipe is a branch pipe that discharges the cooling liquid received from one end portion from two other end portions, and the two other end portions are connected to the first and second cooling liquid supply ports. A cooling structure for a rotating electrical machine that is inserted from one direction and connected to a cover member. The cooling structure for a rotating electrical machine according to claim 1 or 2,
A cooling structure for a rotating electrical machine, wherein the first and second coolant supply ports are formed to open in an axial end surface of the lead side cover member. In the cooling structure of the rotating electrical machine according to any one of claims 1 to 3,
In order to adjust the amount of the coolant supplied to each of the first and second coolant chambers, the first coolant supply port and the second coolant supply port have different opening diameters, or A cooling structure for a rotating electric machine, wherein inner diameters of the cooling liquid supply pipes connected to the respective cooling liquid supply ports are made different. In the rotating electrical machine cooling structure according to any one of claims 1 to 4,
Cooling of the rotating electrical machine, wherein the coolant entrance path to the first and second coolant chambers is formed in a substantially V shape in an oblique direction that is not orthogonal to the outer peripheral surface of the coil end portion on the radially outer side. Construction.

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