JP2012231647A - Stator cooling structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively cool a coil end by appropriately preventing cooling oil from flowing along an inner peripheral side of a tub.SOLUTION: A stator cooling structure 1 according to this disclosure includes: a stator core 11; a coil end 14a projecting from an axial end of the stator core; a tub 20, 20A, and 20B which is disposed along the outer peripheral face of the coil end on the upper side in the vertical direction relative to the outer peripheral face of the coil end and has a plurality of communication holes 50 communicating the inner peripheral side with the outer peripheral side; and a cooling oil supply portion 70 supplying cooling oil to the outer peripheral side of the tub. The tub includes a plurality of horizontal portions 30 on the inner peripheral side and is formed to have a stepped shape viewed in the axial direction of the stator core, and an opening 50a of the communication hole on the inner peripheral side of the tub is disposed in the horizontal portion.

Description

  The present invention relates to a stator cooling structure for cooling coil ends with cooling oil.

  Conventionally, an oil dropping hole is formed in the frame above the coil end, an insulating member having a tongue-like cut is provided below the oil dropping hole, and the lubricating oil flowing out through the oil dropping hole is cut into a tongue A structure that leads to the coil end portion is known (for example, see Patent Document 1).

  Further, a stator cooling structure is known that includes a flange extending along the outer peripheral surface of the coil end at a position spaced vertically upward from the outer peripheral surface of the coil end (see, for example, Patent Document 2). The rod includes a plurality of communication holes that allow communication between the inner peripheral side and the outer peripheral side. The cooling oil supplied to the outer peripheral side of the rod moves from the outer peripheral side to the inner peripheral side of the rod through the plurality of communication holes due to gravity, and drops on the coil end. Both the inner peripheral side and the outer peripheral side of the collar are formed with curved surfaces corresponding to the outer peripheral surface of the coil end.

JP 2010-76678 A JP 2004-180376 A

  However, in the configuration described in Patent Document 1, when the supply amount of the cooling oil is not sufficient, the cooling oil that should fall downward from the oil dripping hole of the frame does not fall downward to the insulating member. There is a case where a sufficient amount of cooling oil cannot be supplied to the coil end by being transmitted through the back surface (lower surface) of the frame.

  Moreover, in the structure of said patent document 2, since the inner peripheral side of the coffin is formed in the curved surface, the cooling oil which came out to the inner peripheral side of the coffin becomes easy to propagate along the inner peripheral side of the coffin. In particular, when the inner circumferential side of the kite is a curved surface, the cooling oil that travels on the inner circumferential side of the kite increases the circumferential speed component, and therefore, along with the surface tension, reaches the circumferential end of the kite. It tends to travel along the inner periphery of the kite.

  Therefore, an object of the present invention is to provide a stator cooling structure that can appropriately prevent the cooling oil from propagating along the inner peripheral side of the rod and effectively cool the coil end.

In order to achieve the above object, according to one aspect of the present invention, a stator core;
A coil end protruding from an axial end of the stator core;
A scissor provided with a plurality of communication holes that are disposed vertically above the outer peripheral surface of the coil end along the outer peripheral surface of the coil end and communicate with the inner peripheral side and the outer peripheral side;
A cooling oil supply section for supplying cooling oil to the outer peripheral side of the basket,
The scissors are provided with a plurality of horizontal portions on the inner peripheral side, and the inner peripheral side is formed in a step shape when viewed in the axial direction of the stator core,
The stator cooling structure is provided in which the opening of the communication hole on the inner peripheral side of the flange is disposed in the horizontal portion.

  ADVANTAGE OF THE INVENTION According to this invention, the stator cooling structure which can prevent a cooling oil from propagating along the inner peripheral side of a flame | frame appropriately, and can cool a coil end effectively is obtained.

It is a perspective view which shows the stator cooling structure 1 by one Example of this invention. It is the figure which looked at the stator cooling structure 1 shown in FIG. 1 in the stator axial direction. It is the perspective view which looked at the collar 20 from upper direction. It is a figure which shows typically the flow of the cooling oil supplied to the eaves. FIG. 3 is a diagram schematically showing a cooling oil dropping mode from a communication hole 50 of each discharge chamber 202 in FIG. 2. It is explanatory drawing of the main effect by the scissors 20 of a present Example, and is a figure which shows typically the behavior tendency of the cooling oil in the inner peripheral side of a scissors by contrast with a comparative example. It is an enlarged view of the P section of FIG. It is a figure which shows the alternative structure of the structure shown in FIG. It is the perspective view which looked at the bag 20A by another Example from the upper direction. It is a figure which shows the cross sectional view of the collar 20B by further another Example.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing a stator cooling structure 1 according to an embodiment of the present invention. FIG. 2 is a view of the stator cooling structure 1 shown in FIG. 1 as viewed in the stator axial direction.

  Here, for convenience of explanation, it is assumed that the stator 10 is mounted in such a direction that its axial center extends in a horizontal plane. Moreover, the stator 10 shall be mounted in the direction in which the vertical direction in FIG. 2 is the vertical direction. That is, in FIGS. 1 and 2, the xy plane corresponds to the horizontal plane, and the downward direction of the z axis corresponds to the downward direction of the vertical direction. However, the mounting method (direction) of the stator 10 is arbitrary.

  Further, in the following description, the terms “axial direction”, “circumferential direction”, and “radial direction” are based on the axial center of the stator 10 unless otherwise specified. Further, the term “upper” represents the upper side in the vertical direction in the usage state of the stator 10, and the term “lower” represents the lower side in the vertical direction in the usage state of the stator 10. For example, when the stator 10 is a stator for a rotating electrical machine as a driving force source for a vehicle such as a hybrid vehicle or an electric vehicle, the state mounted on the vehicle corresponds to the use state.

  In FIG. 2, the flange 20 constituting the stator cooling structure 1 is shown as a cross-sectional view cut along a plane connecting the centers of communication holes 50 (described later) in order to facilitate understanding of the configuration.

  Stator 10 includes a stator core 11 and a coil 14. The stator 10 is configured as an armature for a rotating electrical machine. The term “rotary electric machine” includes any of a motor (electric motor), a generator (generator), and a motor / generator having both functions. In the illustrated example, although not illustrated, a rotor including a permanent magnet or an electromagnet is provided on the radially inner side of the stator core 11.

  The stator core 11 has a cylindrical shape as a whole, and may be formed from an annular ferromagnetic laminated steel plate, or may be formed using a powdered material obtained by pressure-forming magnetic material powder. The stator core 11 has a cylindrical core body 11a, a plurality of teeth 11b protruding radially inward from the core body 11a and formed at predetermined intervals along the circumferential direction, and a diameter from the outer peripheral surface of the core body 11a. And a protruding portion 11c protruding outward in the direction. As shown in FIG. 2, the protrusion 11 c may be formed at a position that equally divides the outer periphery of the core body 11 a into three. The stator core 11 may be fastened and fixed to a case (not shown) by a fastening bolt 90 inserted in an insertion hole formed in the protrusion 11c.

  The coil 14 is wound around a slot formed between the plurality of teeth 11 b of the stator core 11. The coil end 14 a is a part of the coil 14 and corresponds to a portion protruding from the axial end of the stator core 11. The coil end 14 a may be formed at both ends of the stator core 11 in the axial direction. In this case, a later-described flange 20 constituting the stator cooling structure 1 may be provided corresponding to each coil end 14a, or may be provided only for one of the coil ends 14a.

  The configuration of the stator 10 may be arbitrary as long as the coil end 14a is defined in relation to the coil 14. For example, the stator 10 may be a stator of an outer rotor type rotating electrical machine, or may be a stator of an inner rotor type rotating electrical machine as illustrated. In the illustrated example, the stator 10 is a stator used for a rotating electrical machine driven by a three-phase alternating current, but may be a stator used for other types of rotating electrical machines.

  Next, the structure of the flange 20 which is a main member constituting the stator cooling structure 1 will be described.

  FIG. 3 is a perspective view of the bag 20 as viewed from above.

  The gutter 20 has a function of dripping the supplied cooling oil onto the coil end 14a in order to cool the coil end 14a. Hereinafter, the terms “inner peripheral side” and “outer peripheral side” will be used to describe the components of the flange 20. The inner circumferential side corresponds to the side facing the radially inner side of the stator 10 (vertical lower side), and the outer circumferential side corresponds to the side facing the radial outer side of the stator 10 (vertical upper side).

  The collar 20 is formed of an insulating material (for example, resin). However, the collar 20 may be formed of a material other than an insulating material such as metal. The flange 20 may be configured by combining a plurality of members, or may be integrally formed.

  As shown in FIGS. 1 and 2, the flange 20 is disposed vertically above the outer peripheral surface of the coil end 14a. The outer peripheral surface of the coil end 14a refers to a radially outer surface of the coil end 14a (in the illustrated example, a cylindrical surface corresponding to the cylindrical coil end 14a). For example, the flange 20 may be attached to the stator core 11 or may be attached to a case (not shown). In the illustrated example, the flange 20 is fastened and fixed together with the stator core 11 to the case using the upper two protrusions 11c. More specifically, the flange 20 has a mounting portion 22 that extends toward the inner peripheral side at both ends in the circumferential direction, and the mounting portion 22 is fastened and fixed together with the protruding portion 11c. The flange 20 is provided to be separated from the outer peripheral surface of the coil end 14a in the vertical direction. In addition, although the separation distance is arbitrary, in order to save space, the flange 20 may be set to a minimum necessary distance to ensure an appropriate clearance that does not interfere with the outer peripheral surface of the coil end 14a. .

  As shown in FIGS. 1 and 2, the flange 20 is disposed along the outer peripheral surface of the coil end 14a. The flange 20 may be arranged along at least a part of the outer peripheral surface of the coil end 14a. Preferably, in order to increase the cooling capacity, the coil 20 has a wide angle range (angle range viewed in the axial direction) as much as possible. It arrange | positions along the outer peripheral surface of the end 14a. In the illustrated example, the flange 20 is provided so as to face the outer peripheral surface of the upper half of the coil end 14a from above in the vertical direction.

  The flange 20 includes a plurality of horizontal portions 30 (hereinafter referred to as inner peripheral side horizontal portions 30) on the inner peripheral side. One unit of the inner peripheral horizontal portion 30 is a portion (region) having a substantially continuous surface extending on the same horizontal plane. Note that “substantially continuous” means that one inner peripheral horizontal portion 30 may include an additional portion such as a concave portion 52 or a convex portion 54 described later. Thus, for example, the two inner horizontal portions 30 mean that each extends on a horizontal plane having a different height, or each extends in the same water surface but is discontinuous with each other. . In the illustrated example, the basket 20 has five inner peripheral side horizontal portions 30. More specifically, as shown in FIG. 2, the inner peripheral side horizontal portion 30 has one in the center facing the highest portion of the outer peripheral surface of the coil end 14a and two on each side in the circumferential direction. Five are provided. Each inner peripheral horizontal portion 30 may be set in such a manner that the circumferential direction is longer than the axial direction.

  As shown in FIG. 2, the plurality of inner peripheral horizontal portions 30 are arranged in such a manner that the inner peripheral side of the flange 20 is stepped when viewed in the axial direction. In the illustrated example, the five inner peripheral side horizontal portions 30 are set at the highest position in the center along the outer peripheral surface of the opposing coil end 14a. The height located on the side is set higher than the height located on the outer side in the circumferential direction. As shown in FIG. 2, a vertical wall portion 32 extending perpendicularly to the inner peripheral horizontal portion 30 is formed between the adjacent inner peripheral horizontal portions 30. In other words, two adjacent inner peripheral horizontal portions 30 having different heights are continuous via the vertical wall portion 32 extending vertically. The vertical length of the vertical wall portion 32 corresponds to the height of the staircase “staircase”. The vertical lengths of the vertical wall portions 32 formed between the adjacent inner peripheral horizontal portions 30 may be the same or different. For example, as in the illustrated example, the vertical length of each vertical wall portion 32 is such that the lower end of each vertical wall portion 32 is spaced from the outer peripheral surface of the coil end 14a by the same distance in the radial direction. It may be set.

  The flange 20 includes a plurality of horizontal portions 40 (hereinafter referred to as an outer peripheral side horizontal portion 40) on the outer peripheral side. As shown in FIG. 2, the outer peripheral side horizontal portion 40 is provided with respect to the inner peripheral side horizontal portion 30. That is, the outer peripheral side horizontal portion 40 is formed on the back side (vertical direction upper side) of the inner peripheral side horizontal portion 30. As shown in FIG. 3, a peripheral wall portion 42 is erected on the outer edge (boundary) of the outer peripheral side horizontal portion 40 toward the outer peripheral side. That is, the peripheral wall portion 42 is provided for each of the outer peripheral side horizontal portions 40 so as to surround the outer peripheral side horizontal portion 40. The peripheral wall portion 42 defines a discharge chamber 202 to be described later with respect to each outer peripheral side horizontal portion 40 with the outer peripheral side horizontal portion 40 as a bottom portion.

  The flange 20 includes a plurality of communication holes 50 that allow communication between the inner peripheral side and the outer peripheral side. The communication hole 50 is formed to have an opening (discharge-side opening) 50a (see FIG. 7) in the inner peripheral side horizontal portion 30. In the illustrated example, the communication hole 50 is formed so as to have an opening 50a in the vicinity of the approximate center of the inner peripheral side horizontal portion 30 (near the middle in the circumferential direction). The communication hole 50 is formed to have an opening (opening side opening) 50 b (see FIG. 7) in the outer peripheral side horizontal portion 40. In the illustrated example, the communication hole 50 is formed in such a manner that the inner peripheral side and the outer peripheral side communicate in the vertical direction in the outer peripheral side horizontal portion 40 and the inner peripheral side horizontal portion 30. The position of the opening 50 b on the introduction side of the communication hole 50 may be a place other than the outer peripheral side horizontal portion 40. Further, the direction of the communication hole 50 (communication direction) is not necessarily the vertical direction, and may be any direction as long as the inner peripheral side horizontal portion 30 has the discharge side opening 50a.

  In the eaves 20, an oil distribution path 200 for distributing the cooling oil supplied to the eaves 20 to the plurality of communication holes 50 is formed on the outer peripheral side of the eaves 20.

  As shown in FIG. 3, the oil distribution path 200 includes a plurality of chambers 202 and 204 partitioned by partition walls 222 and 224, and an inter-chamber communication path that communicates between the adjacent chambers 202 and 204. In the illustrated example, the inter-chamber communication path is defined by the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224, as will be described later. In the oil distribution path 200, the branching location and the flow direction of the cooling oil are determined by the formation position of the inter-chamber communication path and the height relationship of the bottom surfaces of the different inter-chamber communication paths.

  The chamber 202 is a chamber in which the communication hole 50 described above is formed, and is also referred to as a discharge chamber 202 hereinafter. In the illustrated example, the discharge chamber 202 is a space whose bottom surface is constituted by the outer peripheral horizontal portion 40 and surrounded by the peripheral wall portion 42 as described above. The partition wall 224 constitutes a part of the peripheral wall portion 42 of the discharge chamber 202.

  The chamber 204 is a chamber that branches the oil distribution path by distributing the cooling oil introduced into the chamber 204 to a plurality of inter-chamber communication paths, and is also referred to as an oil distribution chamber 204 hereinafter. The oil distribution chamber 204 cooperates with the inter-chamber communication passage to distribute the cooling oil supplied to the tank 20 to the plurality of discharge chambers 202 (and thus the plurality of communication holes 50 formed therein) at a desired ratio. To function. In the example shown in the drawing, the oil distribution chambers 204 are respectively arranged in a manner adjacent to each of the three discharge chambers 202 on the center side in the axial direction. The oil distribution chambers 204 are adjacent to each other in the circumferential direction, and the central oil distribution chamber 204 has a bottom surface at a height higher than the oil distribution chambers 204 on both sides in the circumferential direction. The height of the bottom surface of each oil distribution chamber 204 may be the same as the height of the bottom surface of the discharge chamber 202 adjacent to each other in the axial direction (that is, the height of the outer peripheral side horizontal portion 40). In the example shown in the figure, the chambers 202 and 204 are formed in a tank shape that opens upward, but are covered with a lid or the like as long as a flow path such as an inter-chamber communication path to the basket 20 is secured. May be.

  The oil distribution chamber 204 is defined by partition walls 222 and 224 and a wall portion 226.

  The partition wall 222 functions to partition each oil distribution chamber 204 in the circumferential direction, and also functions to form a circumferential passage of cooling oil from the oil distribution chamber 204 to the other oil distribution chamber 204 or the discharge chamber 202. Due to the latter function, the upper edge of the partition wall 222 is set to such a height that the cooling oil can flow down to the adjacent chambers 202 and 204 in the circumferential direction. Therefore, the upper edge of the partition 222 constitutes an inter-chamber communication path. More specifically, the upper edge of the circumferential partition wall 222 of the central oil distribution chamber 204 is lower than the upper edge of the axial partition wall 224 and the upper edge of the wall portion 226 of the central oil distribution chamber 204. Set to Further, for each of the oil distribution chambers 204 on both sides in the circumferential direction of the central oil distribution chamber 204, the upper edge of the partition wall 222 on the outer side in the circumferential direction as viewed from the central oil distribution chamber 204 is the axial direction of the oil distribution chamber 204. The upper edge of the partition wall 224 (or the peripheral wall portion 42 extending in the same plane continuously to the partition wall 222) and the height lower than the upper edge of the wall portion 226 are set. However, here, the height of the upper edge of the partition wall 224 refers to the height of the upper edge of the partition wall 224 at a portion where a notch 224a described later is not provided.

  The partition wall 224 is disposed on the outer side in the axial direction of each oil distribution chamber 204 (on the discharge chamber 202 side). The partition wall 224 functions to partition each oil distribution chamber 204 and each discharge chamber 202 axially adjacent to each other in the axial direction, and a passage in the axial direction of cooling oil from the oil distribution chamber 204 to the discharge chamber 202. Fulfills the function of forming. Due to the latter function, the upper edge of the partition wall 224 is set to such a height that the cooling oil can flow down to the discharge chamber 202 adjacent in the circumferential direction. In the illustrated example, the partition 224 is formed with a notch 224a in a part thereof, so that an upper edge having a lower height than other portions is formed. That is, the upper edge of the notch 224a of the partition wall 224 forms an inter-chamber communication path. Note that the partition wall 222 may be formed with a similar notch in a part of the upper edge, so that the height of the upper edge is lower than the surrounding area.

  FIG. 4 is a diagram schematically showing the flow of the cooling oil supplied to the gutter 20. FIG. 5 is a diagram schematically showing a cooling oil dripping mode from the communication hole 50 of each discharge chamber 202 in FIG. 2.

  Cooling oil is supplied to the flange 20 from the outer peripheral side by the cooling oil supply unit 70. In the illustrated example, the cooling oil is supplied to the central oil distribution chamber 204 by the cooling oil supply unit 70 as indicated by an arrow A1 in FIG. The cooling oil supply unit 70 corresponds to a cooling oil introduction unit to the basket 20 and is schematically illustrated. A pipe line, a pump, a reservoir tank, and the like may be connected to the cooling oil supply unit 70. In addition, the cooling oil may be dropped from the cooling oil supply unit 70 to the scissors 20 and introduced in the vertical direction, or may be introduced by being pumped in the axial direction, or the cooling oil to the scissors 20 The introduction mode of is arbitrary.

  The cooling oil introduced into the central oil distribution chamber 204 in this way is transferred to the oil distribution chambers 204 on both sides in the circumferential direction of the central oil distribution chamber 204 as shown by an arrow A2 in FIG. While flowing down beyond the edge, as shown by arrow A3 in FIG. 4, it flows down to the central discharge chamber 202 over the upper edge of the notch 224a of the partition wall 224. The distribution of these flow rates may be adjusted by adjusting the height and width of the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224 (the opening width of the inter-chamber communication path). For example, when the cooling oil is supplied to the five discharge chambers 202 at the same ratio, the flow rate indicated by the arrow A2 and the flow rate indicated by the arrow A3 are 4: 1. Accordingly, with respect to the central oil distribution chamber 204, the height of the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224 are the same, and the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224 The width ratio may be 2: 1.

  The cooling oil distributed to the oil distribution chambers 204 on both sides in the circumferential direction of the central oil distribution chamber 204 in this way is separated into the discharge chamber 202 adjacent in the circumferential direction as shown by an arrow A4 in FIG. While flowing down over the upper edge of the partition wall 222 on the outer side in the circumferential direction when viewed from the central oil distribution chamber 204, the partition wall 224 is moved to the discharge chamber 202 adjacent in the axial direction as indicated by an arrow A5 in FIG. It flows down over the upper edge of the notch 224a. Similarly, the distribution of these flow rates may be adjusted by adjusting the height and width of the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224. For example, when the cooling oil is supplied to the five discharge chambers 202 at the same ratio, the flow rate indicated by the arrow A4 and the flow rate indicated by the arrow A5 are 1: 1. Therefore, with respect to the oil distribution chambers 204 on both sides in the circumferential direction of the central oil distribution chamber 204, the height of the upper edge of the partition wall 222 and the upper edge of the notch 224 a of the partition wall 224 when viewed from the center oil distribution chamber 204. And the ratio of the width of the upper edge of the partition wall 222 to the upper edge of the notch 224a of the partition wall 224 may be 1: 1.

  The cooling oil distributed to the five discharge chambers 202 in this way is transferred from the outer peripheral side of the flange 20 to the inner peripheral side through the communication hole 50 of each discharge chamber 202 as indicated by an arrow A6 in FIG. And then drop by gravity. Thereby, as shown by arrow A6 in FIG. 5, the cooling oil can be dripped onto the outer peripheral surface of the coil end 14a to cool the coil end 14a.

  According to such an oil distribution path 200, a desired ratio of the cooling oil supplied to the eaves 20 is supplied to a plurality of discharge chambers 202 (and thus a plurality of communication holes 50 formed there) along the circumferential direction. Can be distributed. Thereby, it becomes possible to supply cooling oil to the outer peripheral surface of the coil end 14a without unevenness. Further, since the oil distribution path 200 is formed so as not to merge after branching from the oil distribution chamber 204, the ratio of the width of the upper edge of the partition wall 222 to the width of the upper edge of the notch 224a of the partition wall 224 is adjusted. This makes it possible to easily adjust the distribution ratio of the cooling oil to each discharge chamber 202.

  Here, with reference to FIG. 6, the main effect by the scissors 20 of a present Example is demonstrated. FIG. 6 (A) shows the behavior tendency of the cooling oil on the inner periphery side of the ridge in the comparative example, and FIG. 6 (B) shows the behavior tendency in the present embodiment. 6 (A) and 6 (B) show the shape of the inner peripheral side of the ridge when viewed in the same direction as FIG. 2 by line segments T1 and T2, and the cooling oil flowing out to the inner peripheral side of the ridge The liquid droplet is schematically indicated by D. The line segment T2 corresponds to the shapes of the inner peripheral horizontal portion 30 and the vertical wall portion 32.

  The comparative example is a configuration in which the inner peripheral surface of the ridge is formed with a curved surface. In this case, particularly when the supply amount of the cooling oil is small, the cooling oil that has come out from the communication hole to the inner peripheral side of the rod is easily transmitted along the curved surface due to surface tension, as indicated by an arrow B1. Further, since the velocity component in the circumferential direction is obtained when traveling along the curved surface, it becomes easier to follow along the curved surface. Therefore, according to the comparative example, as shown by the arrow B2, the surface tends to travel along the inner peripheral surface of the heel until reaching the circumferential end of the heel. In such a configuration, the coil end may not be uniformly cooled even if the discharge side openings of the communication holes are evenly arranged in the circumferential direction on the inner peripheral surface of the flange.

  On the other hand, according to the present embodiment, the communication hole 50 having the discharge-side opening 50a is formed in the inner peripheral side horizontal portion 30. Thereby, even when the supply amount of the cooling oil is small, the cooling oil that has come out from the communication hole 50 to the inner peripheral side of the rod remains in the inner peripheral side horizontal portion 30 where the communication hole 50 is located and drops (for example, , The communication hole 50 of the central discharge chamber 202 is effectively prevented from flowing along the inner peripheral side of the flange 20 (see arrow B3). Moreover, even when flowing along the inner peripheral side horizontal portion 30 of the ridge 20 (see arrow B4), the cooling oil is dripped at stepped corners (the corners of the inner peripheral side horizontal portion 30 and the vertical wall portion 32). Therefore (refer to arrows B5 and B6), it is effectively prevented that the gas flows along the circumferential end of the flange 20 (an event that occurs in the comparative example). Therefore, according to the present embodiment, the cooling oil can be accurately dropped at a desired position even when the supply amount of the cooling oil is small. Thereby, even when the supply amount of the cooling oil is small, the coil end 14a can be cooled in a desired manner.

  Further, in this embodiment, when each inner peripheral side horizontal portion 30 is provided in a mode in which the circumferential direction is longer than the axial direction, the circumferential direction becomes longer, so that the cooling oil surrounds the inner peripheral side of the flange 20. Propagating in the direction can be more effectively prevented.

  FIG. 7 is an enlarged view of a portion P in FIG. The inner peripheral side horizontal portion 30 may be horizontal around the communication hole 50, but preferably, a concave portion 52 is provided as shown in FIG. The recess 52 may be formed over the entire circumference so as to surround the communication hole 50. By providing the recess 52 around the communication hole 50, the cooling oil attached to the tip of the protruding portion 53 formed by the recess 52 is easily dropped by its own weight. Thereby, it is possible to more effectively prevent the cooling oil from propagating along the inner peripheral side of the flange 20, and the cooling oil can be dropped more accurately at a desired position. Moreover, since the recessed part 52 does not protrude vertically downward from the basic surface (horizontal plane) of the inner peripheral side horizontal part 30, space saving in the vertical direction can be achieved.

  Alternatively, the inner peripheral side horizontal portion 30 may be provided with a convex portion 54 around the communication hole 50 as shown in FIG. 8. The convex portion 54 may be formed over the entire circumference so as to surround the communication hole 50. By providing the convex portion 54 around the communication hole 50, the cooling oil attached to the tip of the convex portion 54 easily falls due to its own weight. Thereby, it is possible to more effectively prevent the cooling oil from propagating along the inner peripheral side of the flange 20, and the cooling oil can be dropped more accurately at a desired position. In the example shown in FIG. 8, the convex portion 54 is formed at a certain distance from the periphery of the communication hole 50, but may be formed at the periphery of the communication hole 50.

  Next, some other embodiments will be described.

  FIG. 9 is a perspective view of a bag 20A according to another embodiment as viewed from above. The scissors 20A according to the present embodiment are different from the scissors 20 according to the above-described embodiments only in the configuration on the outer peripheral side. As shown in FIG. 3, the scissor 20 according to the above-described embodiment includes the oil distribution chamber 204 and the inter-chamber communication path, but these may be omitted. For example, as shown in FIG. 9, the flange 20 </ b> A has a stepped outer peripheral side horizontal portion 40 on the outer peripheral side, and the adjacent outer peripheral side horizontal portions 40 are not partitioned in the circumferential direction. Also in this case, the same effect as described with reference to FIG. 6 can be obtained by providing the same configuration on the inner peripheral side as the bag 20 according to the above-described embodiment.

  FIG. 10 is a diagram showing a cross-sectional view of a bag 20B according to still another embodiment. In FIG. 10, as in FIG. 2, the flange 20 </ b> B is shown as a cross-sectional view cut along a plane connecting the centers of the communication holes 50. The scissors 20B according to this embodiment are different from the scissors 20 according to the above-described embodiments only in the configuration on the outer peripheral side. As shown in FIG. 2 and the like, the kite 20 according to the above-described embodiment has the outer peripheral side horizontal portion 40, but the outer peripheral side may not be horizontal. That is, the bottom surface of the discharge chamber 202 does not need to be configured in a horizontal plane, and may include an inclined surface or a curved surface. For example, as shown in FIG. 10, the flange 20 </ b> B may have an inclined surface 40 </ b> B that is inclined in a direction downward along the circumferential direction toward the communication hole 50. In this case, the opening 50b (see FIG. 7) on the introduction side of the communication hole 50 is provided in a region whose height is lower than the surroundings. When the entire bottom surface of the discharge chamber 202 is configured by the outer peripheral side horizontal portion 40 as in the case of the flange 20 according to the above-described embodiment, the cooling oil is accumulated in the discharge chamber 202 at a uniform depth. The cooling oil can be discharged uniformly from 50. On the other hand, when the inclined surface 40B is inclined toward the opening 50b on the introduction side of the communication hole 50 as in the case 20B according to the present embodiment, the amount of cooling oil introduced into the discharge chamber 202 is small. However, the cooling oil can be efficiently guided toward the opening 50b on the introduction side of the communication hole 50.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the inner peripheral horizontal portion 30 extends not only to the inner peripheral side of the discharge chamber 202 in the ridge 20, but also to the inner peripheral side of the oil distribution chamber 204 in the ridge 20. It is also possible to extend only to the inner peripheral side of the discharge chamber 202 in the tub 20. In this case, the inner peripheral side of the oil distribution chamber 204 in the ridge 20 may be formed by a surface including an inclined surface or a curved surface. In this case, a protrusion or groove that partitions the inner peripheral side portion of the oil distribution chamber 204 in the flange 20 from the inner peripheral horizontal portion 30 (the inner peripheral side of the discharge chamber 202 in the flange 20) may be formed.

  Further, in the above-described embodiment, the inner peripheral side horizontal portion 30 is provided over the entire inner peripheral side of the discharge chamber 202 in the ridge 20, but the inner peripheral side horizontal portion 30 is provided in the discharge chamber in the ridge 20. It may be formed on a part of the inner peripheral side of 202. That is, the inner peripheral horizontal portion 30 may be provided in an appropriate range around the discharge-side opening 50a of the communication hole 50 in a mode in which the effect described with reference to FIG. .

  In the above-described embodiment, one communication hole 50 is provided for one inner peripheral horizontal portion 30, but the number of communication holes 50 is arbitrary. For example, two or more communication holes 50 may be set for one inner peripheral horizontal portion 30. In this case, the arrangement form is also arbitrary. For example, the two or more communication holes 50 may be arranged side by side in the axial direction, or may be arranged in a staggered manner apart from each other in the axial direction and the circumferential direction. You may arrange | position along with the circumferential direction.

  In the embodiment described above, the discharge-side opening 50a of the communication hole 50 is located at the center of the inner peripheral horizontal portion 30, but the present invention is not limited to this. However, it is desirable that the discharge-side opening 50 a of the communication hole 50 be separated from the vertical wall portion 32 of the inner peripheral horizontal portion 30 by a predetermined distance or more. This is to prevent the cooling oil coming out from the opening 50 a on the discharge side of the communication hole 50 from being transmitted through the vertical wall portion 32.

  Moreover, in the Example mentioned above, although the whole vertical wall part 32 is extended in the perpendicular direction, one part may incline and the like. For example, the vertical wall portion 32 forms a right angle with respect to the one inner peripheral horizontal portion 30 to be connected, but may form an angle of less than 90 degrees with respect to the other inner peripheral horizontal portion 30 to be connected. Good (see, for example, vertical wall 322 in FIG. 10). Also in this case, since dripping occurs at a right angle between the inner peripheral horizontal portion 30 and the vertical wall portion 32, the effect described in FIG. 6 can be partially enjoyed. Moreover, the vertical wall part 32 may be comprised from an inclined surface and may make an angle of less than 90 degree | times with respect to the both inner peripheral side horizontal parts 30 to connect. In this case, although dripping at a right angle between the inner peripheral horizontal portion 30 and the vertical wall portion 32 cannot be expected, the effect of dripping on the inner peripheral horizontal portion 30 (see arrow B3 in FIG. 6) is enjoyed. be able to.

  Further, in the above-described embodiment, each oil distribution chamber 204 is arranged in a manner adjacent to the circumferential direction, each discharge chamber 202 is arranged in a manner adjacent to the circumferential direction, and the three discharge chambers 202 and three in the center side are arranged. The oil distribution chambers 204 are arranged in an axially adjacent manner, but such an arrangement is merely an example, and the oil distribution chamber 204 and the discharge chamber 202 are arranged adjacent to each other in the circumferential direction. The chamber 202 and the discharge chamber 202 are disposed adjacent to each other in the axial direction, the oil distribution chamber 204 and the oil distribution chamber 204 are disposed adjacent to each other in the axial direction, or a combination thereof. Various arrangements are possible. Further, the discharge chamber 202 may further have a function of the oil distribution chamber 204 (that is, a function of distributing the cooling oil to the adjacent chambers). You may further have a function (namely, a function which has a communicating hole and discharges cooling oil below).

  In the above-described embodiment, the inter-chamber communication path is defined by the upper edge of the partition wall 222 and the upper edge of the notch 224a of the partition wall 224, but the openings (upper edge) formed in the partition wall 222 and the partition wall 224. May be defined by holes that do not extend to The shape of the notch 224a (or opening) is also arbitrary, and may be a polygonal shape such as a circle or a rectangle, or a partial shape of an ellipse.

  In the above-described embodiment, the openings 50a and 50b of the communication hole 50 are circular, but may be other shapes (for example, a polygon such as a rectangle or an ellipse). Further, the opening areas of the openings 50 a and 50 b of the communication hole 50 may be common to all the communication holes 50 or may be different depending on the communication holes 50.

  Moreover, in the Example mentioned above, although the outer peripheral surface of the coil end 14a was a cylindrical peripheral surface, the shape of the outer peripheral surface of the coil end 14a may be arbitrary.

DESCRIPTION OF SYMBOLS 1 Stator cooling structure 10 Stator 11c Projection part 11 Stator core 11a Core main part 11b Teeth 14 Coil 14a Coil end 20, 20A, 20B 桶 22 Mounting part 30 Inner peripheral side horizontal part 32 Vertical wall part 40 Outer peripheral side horizontal part 40B Inclined surface 42 Peripheral wall portion 50 Communication hole 50a Discharge side opening 50b Inlet side opening 52 Concavity 53 Protrusion portion 54 Convex portion 70 Cooling oil supply portion 90 Fastening bolt 200 Oil distribution path 202 Discharge chamber 204 Oil distribution chamber 222, 224 Partition 224a Notch 226 wall

Claims (5)

A stator core;
A coil end protruding from an axial end of the stator core;
A scissor provided with a plurality of communication holes that are arranged vertically above the outer peripheral surface of the coil end along the outer peripheral surface of the coil end and communicate with the inner peripheral side and the outer peripheral side;
A cooling oil supply unit that supplies cooling oil to the outer peripheral side of the basket,
The scissors are provided with a plurality of horizontal portions on the inner peripheral side and the inner peripheral side is formed in a step shape when viewed in the axial direction of the stator core,
The stator cooling structure according to claim 1, wherein the opening of the communication hole on the inner peripheral side of the flange is disposed in the horizontal portion.   The stator cooling structure according to claim 1, wherein a convex portion or a concave portion is provided around the communication hole on an inner peripheral side of the flange. An oil distribution path for distributing the cooling oil supplied from the cooling oil supply unit to the plurality of communication holes is formed on the outer peripheral side of the flange.
The oil distribution path has a plurality of chambers partitioned by partition walls, and an inter-chamber communication passage formed in the partition walls and communicating between the adjacent chambers.
The plurality of chambers include at least one oil distribution chamber that divides the oil distribution path by distributing cooling oil introduced into the chamber to the plurality of inter-chamber communication paths, and a plurality of the communication holes formed therein. A discharge chamber,
The stator cooling structure according to claim 1, wherein the oil distribution path is formed so as not to merge after branching from the oil distribution chamber. The scissors include a plurality of horizontal portions on the outer peripheral side,
The stator cooling structure according to claim 3, wherein the discharge chamber is formed in a horizontal portion on the outer peripheral side.   The stator cooling structure according to any one of claims 1 to 4, wherein a dimension of the horizontal portion on the inner peripheral side of the flange is longer in the circumferential direction than in the axial direction of the stator core.

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