Rotor structure

Abstract

Provide a rotor structure. 【Solution means】It is composed of a core sheet, two ring covers, and a hollow shaft. The core sheet has a horizontal side surface and a plurality of relief holes arranged at equal angles. Each of the ring covers has a horizontal inner surface that contacts the outermost horizontal side surface of the core sheet, and the horizontal inner surface of the ring cover has a guide chunk that corresponds one by one to the relief hole. A guide groove is formed on the end face of the guide chunk, the oil passage inlet of the ring cover is located on the inner ring surface of the ring cover, and the oil passage outlet is located on the outer ring surface of the ring cover. The core sheet and the two ring covers are covered on the hollow shaft, and the oil passage inlet of the ring cover is fluidly connected to the oil supply hole of the hollow shaft. The guide chunk decelerates the flow velocity of separation into the oil passage by centrifugal force and keeps the amount of oil supplied and drained consistent.

Description

Technical Field

[0001] The present invention relates to a rotor structure, and more particularly to a rotor structure having a flow path structure capable of improving the temperature distribution on both side surfaces.

Background Art

[0002] When the rotor of a motor rotates at high speed, high temperature is generated, so it was necessary to install a cooling oil passage inside to assist heat dissipation. By installing a rotor oil passage, coolant is injected from the hollow axis of the rotor. A plurality of through holes are formed in the rotor core, and an axial cooling oil passage is formed in the through hole itself, or an axial cooling oil passage is formed by inserting an oil pipe into the through hole. The oil supply hole of the cooling oil passage is fluidly connected to the hollow axis, and the oil drain hole of the cooling oil passage is located in the outermost core (or end caps on both sides). The internal oil passage of the core can be installed at any position of the core. For example, the cooling oil passage may be adjacent to the periphery of the permanent magnet inside the core, or the coolant may be flowed so as to directly contact the permanent magnet.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Due to the centrifugal force of the rotor, the cooling liquid is introduced radially from the axial center into the core, and then radially led out from both sides of the core to the oil drain holes. However, if there are tolerances in the combination of cores, or if tolerances occur after combination due to differences in the materials of the cores and the end caps on both sides, gaps will occur on the adhering surfaces between the cores or between the core and the end cap. Due to the action of inertia during rotation, the fluid led out from the hollow axial center to the core is separated along the tangential direction and flows out from the gaps between the adhering surfaces, making it impossible to surely enter the rotor interior. This means that the amounts of oil contained in the plurality of axial flow paths within the same time are all different. Also, if the cooling liquid does not completely enter the oil path, the internal oil amount distribution will become uneven, differences will occur in the flow velocities of different flow paths inside the rotor, affecting the heat exchange rate, and particularly affecting the temperature distribution at the positions of the end caps on both sides.

[0004] Therefore, as a result of intensive studies, the inventors have found that the above object can be achieved by adopting the following configuration, and have thus completed the present invention.

[0005] The present invention has been made through the intensive research of the inventor in view of the above problems, and its object is to provide a rotor structure.

Means for Solving the Problems

[0006] To solve the above problems, a rotor structure according to an aspect of the present invention includes at least one core sheet, two ring covers, and a hollow shaft. The at least one core sheet has a horizontal side surface and a plurality of through holes. The plurality of through holes are mainly composed of a plurality of relief holes and a plurality of magnet mounting holes. The contours of the relief holes are the same and are arranged equiangularly at equal distances from the center of the circle. The ring cover has a horizontal inner surface that contacts the outermost horizontal side surface of the core sheet, and the horizontal inner surface has a plurality of guides With protrusions having, and the guides With protrusionsA part of the guide groove is formed on each end face thereof, a flow path inlet located on the inner ring surface of the ring cover is formed in the other part of several guide grooves, and a flow path outlet located on the outer ring surface of the ring cover is formed in the other part of several other guide grooves. The flow path inlet and the flow path outlet are provided so as to intersect along the circumferential direction. The core sheet and the two ring covers are covered outside the hollow shaft, and the flow path inlet of the ring cover is fluidly connected to the oil supply hole of the hollow shaft. Guide With protrusions enters the inside of the relief hole with respect to the horizontal inner surface.

[0007] Guide With protrusions prevents the coolant from leaking from the adhered surface, decelerates the flow rate of the coolant entering the flow path of the core sheet from the ring covers on both sides, increases the residence time of the coolant at the axis, and enables sufficient heat exchange with the axis.

[0008] Preferably, an oil pipe having a plurality of oil holes distributed along the axial direction is installed inside the hollow shaft, and the coolant inside the hollow shaft has directivity and the flow rate is limited.

[0009] Preferably, Guide With protrusions has a rounded corner at the boundary between the side surface and the end surface. When the coolant is guided from the core to the ring cover, it flows easily and smoothly along the boundary.

[0010] Preferably, Guide With protrusions has a space between its outer contour and the contour of the relief hole, so that Guide With protrusions further has the function of guiding the leaked coolant to the axial cooling flow path and stabilizing the internal oil quantity.

[0011] Preferably, a radial guide groove recessed with respect to the horizontal inner surface is formed in the other part of the guide groove and is used to maintain a stable flow rate.

[0012] Preferably, the radial guide groove and Guide With protrusionsThe boundary with the guide groove formed therein is an arc guide groove, which further decelerates the flow velocity of the coolant flowing into / out of the radial guide groove from the radial direction.

[0013] Preferably, a part of the side surface of the guide With protrusions is directed towards the hollow shaft, and the partial side surface has an arc surface extending in the circumferential direction, minimizing the coolant dispersed outside the flow path.

[0014] Preferably, the number of the core sheets is plural and they are offset along the circumferential direction.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0016] Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution means of the invention.

[0017] First, with reference to FIGS. 1 to 7, an embodiment of the rotor structure according to the present invention will be described.

[0018] The rotor structure includes a rotor core 20, ring covers 40A and 40B, and a hollow shaft 50. The rotor core 20 includes at least one core sheet 21. The hollow shaft 50 has an outwardly expanding base 55 and an outer ring surface 56 located on the side surface.

[0019] The ring cover 40A, the rotor core 20, and the ring cover 40B are sequentially covered on the outer ring surface 56 of the hollow shaft 50, and the inner ring surface of the ring cover 40A is restricted inside the base 55. The outer ring surface 56 conforms to the structure of the inner ring surface of the core sheet 21, and the core sheet 21 rotates synchronously with the hollow shaft 50. The above-mentioned structural conformity means that, for example, the inner ring surface positioning the core sheet 21 has bumps 215 fitted into the axial grooves 561 of the outer ring surface 56 and is also used for assisting in positioning. The end lock member 10 is locked from the other side surface of the hollow shaft 50, sandwiches the ring cover 40B, and forms a cooling oil passage inside the rotor.

[0020] The core sheets 21 are located on both sides and are horizontal, and have core side surfaces 211 and 212 parallel to each other and a plurality of through holes penetrating the core side surfaces 211 and 212. The through holes include a plurality of relief holes 23 and a plurality of magnet mounting holes 24. The contours of each of the relief holes 23 are the same and are arranged equiangularly at an equal distance from the center of the circle. In addition to reducing the weight of the rotor, the relief holes 23 are also used to define an axial flow path inside the core. The plurality of magnet mounting holes 24 are spaced from the center of the circle with respect to the relief holes 23 and are used to accommodate the permanent magnets 30.

[0021] A relief hole (a hollow channel is formed) and a flow path hole (a flow path is formed) are individually formed inside the core. In this embodiment, the relief hole is directly adopted to form the flow path, the size of the flow path of the relief hole and the oil storage amount are increased, and at the same injection speed of the coolant, the flow rate of the coolant is decelerated so that sufficient heat exchange can be performed inside the core. In a preferred embodiment, the relief hole 23 is made as close as possible to the magnet mounting hole 24 so that the coolant can take away the high temperature of the permanent magnet 30.

[0022] Compared with the prior art, a flow path hole communicating with the magnet mounting hole is opened around the magnet mounting hole, and the coolant directly contacts the permanent magnet to achieve a cooling effect. However, if the flow resistance of the coolant becomes too large due to the size of the flow path hole, the coolant will be directly introduced into the flow path hole with a small size or it will be difficult to be led out at the junction of the radial flow path and the axial flow path due to the centrifugal force of rotation. The flow rates of all the cooling oil paths become uneven, affecting the temperature distribution of the entire rotor. In the prior art, since there are gaps on the adhering surfaces of adjacent members, actually less coolant enters the cooling oil path. When the rotor stops, the coolant will no longer flow out from the oil drain holes on both sides of the core, and the coolant accumulates inside, and the accumulated coolant enters the oil supply hole of the core. Therefore, when the coolant is not continuous during operation, the heat exchange effect is clearly limited.

[0023] In this embodiment, the structures of the ring covers 40A and 40B are the same. Taking the ring cover 40A as an example, it has a horizontal inner surface 401 and an outer surface 402. The inner surface 401 contacts the core side surface 212 which is the outermost of the rotor core 20, and the outer surface 402 is spaced apart from the rotor core 20 and directed outward. On the horizontal inner surface 401 of the ring cover 40A, there are a plurality of guides With protrusions 41 corresponding one by one to the quantity and position of the plurality of relief holes 23. When the assembly of the rotor is completed, the guide With protrusions 41 enters the inside of the relief hole 23 with respect to the horizontal inner surface 401. That is, the guide With protrusions41 is located within the inner ring wall 231 formed inside the core sheet 21 of the relief hole 23, and rotates the ring cover 40A and the core sheet 21 (hollow shaft 50) synchronously.

[0024] Guide With protrusions Each of the guides 41 has a side surface 411 and an end surface 412, and several guides With protrusions A part of the oil supply guide groove 451 is formed in the guide 41, and several other guides With protrusions A part of the oil discharge guide groove 452 is formed in the guide 41. The oil supply guide groove 451 is recessed inward along the end surface 412 and the side surface 411 of the guide 41, forming a bent flow path. The guide With protrusions extends axially along the side surface 411 of the guide 41, and a straight radial guide groove 461 is formed to be recessed in the inner side surface 401 of the ring cover 40A. Next, a flow path inlet 45A is formed in the inner ring surface 403 of the ring cover 40A. The oil discharge guide groove 452 is recessed inward along the end surface 412 and the side surface 411 of the guide 41, forming a bent flow path. The guide With protrusions extends outward along the side surface 411 of the guide 41, and a straight radial guide groove 462 is formed to be recessed in the inner side surface 401 of the ring cover 40A. Next, a flow path outlet 45B is formed in the outer ring surface 404 of the ring cover 40A. With protrusions extends outward along the side surface 411 of the guide 41, and a straight radial guide groove 462 is formed to be recessed in the inner side surface 401 of the ring cover 40A. Next, a flow path outlet 45B is formed in the outer ring surface 404 of the ring cover 40A. With protrusions extends outward along the side surface 411 of the guide 41, and a straight radial guide groove 462 is formed to be recessed in the inner side surface 401 of the ring cover 40A. Next, a flow path outlet 45B is formed in the outer ring surface 404 of the ring cover 40A.

[0025] Specifically, the direction of the cooling oil path according to this embodiment is that the rotor cooling oil path is injected from the axis of the hollow shaft 50 and flows into the flow path inlet 45A of the ring cover 40A (40B) from the oil supply holes 511 and 512 on both sides of the hollow shaft 50. Next, it enters the inside of the rotor core 20 and is led out to the outside of the rotor from the flow path outlet 45B of the other ring cover 40B (40A).

[0026] As shown in FIGS. 6 and 7, taking the ring cover 40A as an example in the same way, the side surface 411 of the ring cover 40A contacts the core side surface 212 that is the outermost, the oil supply guide groove 451, the oil discharge guide groove 452, and the radial guide grooves 461 and 462 are closed, and the flow path inlet 45A of the remaining inner ring surface 403 is joined to the oil supply hole 511 (see FIG. 3), and the flow path outlet 45B of the outer surface 402 is directed outward. The flow path inlet 45A and the flow path outlet 45B of the ring cover 40A are installed so as to cross each other along the circumferential direction. The flow path inlet 45A of the ring cover 40A and the flow path outlet 45B of the ring cover 40B are fluidly connected to the cooling oil path in the same axial direction, and the flow path inlet 45A of the ring cover 40B and the flow path outlet 45B of the ring cover 40A are fluidly connected to the cooling oil path in the same axial direction. The flow path inlet 45A of the ring cover 40A is aligned with the oil supply hole 511, and the flow path inlet 45A of the ring cover 40B is aligned with the oil supply hole 512 (see FIG. 3). The flow directions of the adjacent flow paths winding around the rotor core 20 along the circumferential direction cross each other, and the temperature distribution of all the rotor cores 20 becomes more uniform.

[0027] guide With protrusions The oil supply guide groove 451 and the oil discharge guide groove 452 formed on the surface of 41 are guide With protrusions Since 41 protrudes from the horizontal inner surface 401, a plurality of guide With protrusions 41 are arranged at equal angles along the circumference, and guide With protrusions The remaining surface (side surface 411) of 41 prevents the coolant from entering from the horizontal adhering surface (401, 212) between the core sheet 21 and the ring cover 40A, reduces the coolant dispersed outside the flow path, allows the coolant to accumulate only on the horizontal adhering surface in front of the side surface 411, enables the coolant to enter the flow path inlet 45A more easily, and stabilizes the internal oil volume.

[0028] Also, based on Bernoulli's theorem, velocity and pressure are inversely proportional. When the rotor rotates, when the high-speed liquid collides with the side surface 411 or the oil supply guide groove 451 of the guide With protrusions 41 of the ring cover 40A, the instantaneous velocity of the liquid decreases, the pressure of the liquid increases, the residence time of the liquid at the axis also increases, the heat exchange amount between the liquid and the axis sufficiently increases, and the oil volume inside the flow path is stabilized.

[0029] As shown in FIG. 5, in addition to the above-described structure, in a preferred embodiment, the guide With protrusions 41 and the contour of the relief hole 23 correspond to each other, and the guide With protrusions A part of the side surface 411 of 41 is directed toward the hollow shaft 50, and the side surface 411 of the said part has an arc surface 413 distributed in the circumferential direction, reducing the coolant dispersed outside the flow path as much as possible. When the above-described contours correspond to each other, it means that the sizes of the contours of the guide With protrusions 41 and the relief hole 23 completely match, or the shapes of the contours are the same but the sizes are different.

[0030] In addition to the above structure, in other embodiments, in the example of FIG. 2, an oil pipe 53 is installed inside the hollow shaft 50, and the oil pipe 53 has a plurality of oil holes 531 distributed along the axial direction. By doing so, the coolant inside the hollow shaft 50 has directivity, the flow rate is limited, the instantaneous rotational speed generated by the rotation of the rotor is decelerated, and the speed of the fluid to be supplied is modified.

[0031] In addition to the above structure, in other embodiments, the guide With protrusions 41 further has a rounded corner 414 at the boundary between the side surface 411 and the end surface 412. By doing so, when the coolant is guided from the rotor core 20 to the ring cover 40A (40B), it flows more smoothly along the rounded corner 414 at the boundary.

[0032] In addition to the above structure, in other embodiments, the guide With protrusions There is further a gap G between the outer contour formed on the side surface 411 of 41 and the contour of the relief hole 23, and the related specific structure is shown in FIGS. 5 and 7. The entering coolant is blocked by the side surface 411 of the guide With protrusions 41 and drawn back into the relief hole 23, the amount of oil inside the flow path is stabilized, the pressures at the flow path outlets 45B on both sides are made to coincide, the amount of oil discharged from both sides is improved, and the temperatures on both sides of the rotor become uniform.

[0033] In addition to the above structure, in other embodiments, the radial guide groove 461 and the guide With protrusions 41 is formed with a fuel supply guide groove 451 (or the radial guide groove 462 and the guide With protrusions 41 is formed with an oil discharge guide groove 452) and the boundary therebetween further presents an arc guide groove 471 recessed inward, further reducing the flow velocity of the coolant flowing in and out in the radial direction in the radial guide groove 461 (radial guide groove 462), further extending the residence time of the coolant in the relief hole 23, and enabling sufficient heat exchange.

[0034] In the embodiment shown in FIG. 1, the number of core sheets 21 of the rotor core 20 is plural, and the plural core sheets 21 are laminated and positioned along the axial groove 561 on the outer circumferential surface of the hollow shaft 50, and the corresponding relief holes 23 are deposited along the axial direction, and the relief holes 23 of the core sheets 21 in different layers form a plurality of flow paths that do not intersect inside the rotor. However, the structure according to the above-described embodiment may also be a rotor core 20 composed of one core sheet 21, and the horizontal inner surfaces 401 of the two ring covers 40A and 40B are respectively adhered to the front core side surface 211 and the rear core side surface 212 of the core sheet 21.

[0035] In addition to the above structure, in other embodiments, the core sheets 21 in different layers are offset at equal angles along the circumferential direction, and the relief holes 23 of the core sheets 21 are also offset along the circumferential direction, and inclined flow paths may be formed in the axial cooling oil path.

[0036] In this embodiment, the radial guide groove 461 of the ring cover 40A and the radial guide groove 462 of the ring cover 40B communicating with the same axial cooling oil path are not on the same straight line. However, in other embodiments, the radial guide groove 461 of the ring cover 40A (of the fuel supply guide groove 451) communicating with the same axial cooling oil path is aligned with the radial guide groove 462 of the ring cover 40B (of the oil discharge guide groove 452).

[0037] The embodiments disclosed this time should be considered illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims be included.

Explanation of Signs

[0038] 10 End lock member 20 Rotor core 21 Core sheet 211 Core side surface 212 Core side surface 215 Bump 23 Relief hole 231 Inner ring wall 24 Magnet mounting hole 30 Permanent magnet 40A Ring cover 40B Ring cover 401 Inner surface 402 Outer surface 403 Inner ring surface 404 Outer ring surface 41 Guide With protrusions 411 Side surface 412 End surface 413 Arc surface 414 Rounded corner 45A Flow path inlet 45B Flow path outlet 451 Oil supply guide groove 452 Oil discharge guide groove 461 Radial guide groove 462 Radial guide groove 471 Arc guide groove 50 Hollow shaft 511 Oil supply hole 512 Oil supply hole 53 Oil pipe 531 Oil hole 55 Base 56 Outer ring surface 561 Axial groove G Gap

Claims

1. At least one core sheet having a horizontal side and a plurality of through holes, the through holes being composed of a plurality of lightening holes and a plurality of magnet mounting holes, the contours of the lightening holes being the same and being arranged equiangularly and equidistantly from the center of the circle; two ring covers, each of the ring covers having a horizontal inner side surface in contact with the outermost horizontal side surface of the core sheet, the horizontal inner side surface having a plurality of guide protrusions corresponding to the relief holes one by one, a portion of a guide groove being formed on an end face of each of the guide protrusions, some of the guide grooves having flow passage inlets located on the inner ring surfaces of the ring covers, and some of the guide grooves having flow passage outlets located on the outer ring surfaces of the ring covers, the flow passage inlets and the flow passage outlets being provided at intervals along the circumferential direction; a hollow shaft having the core sheet and the two ring covers on its outside, the flow passage inlet of the ring cover being fluidly connected to an oil supply hole of the hollow shaft; A rotor structure characterized in that the guide projections enter into the relief holes relative to the horizontal inner surface.

2. 2. The rotor structure according to claim 1, wherein an oil pipe having a plurality of oil holes distributed along the axial direction is installed inside the hollow shaft.

3. 2. The rotor structure according to claim 1, wherein the boundary between the side surface and the end surface of the guide projection has a rounded corner.

4. 2. The rotor structure of claim 1, wherein an outer contour of said guide projection is spaced from said contour of said relief hole.

5. 2. A rotor structure according to claim 1, wherein a radial guide groove is formed in another portion of said guide groove so as to be recessed into said horizontal inner surface.

6. 6. The rotor structure according to claim 5, wherein a boundary between the radial guide groove and the guide groove formed in the guide projection is an arc guide groove.

7. 2. The rotor structure according to claim 1, wherein a portion of a side surface of the guide projection faces the hollow shaft, and the side surface of the portion has an arcuate surface extending in a circumferential direction.

8. 2. The rotor structure according to claim 1, wherein the number of the core sheets is multiple, and the multiple core sheets are stacked in the axial direction of the hollow shaft.

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