JP2019097220A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine capable of appropriately supplying a liquid refrigerant supplied to a hollow portion of a rotor shaft to a rotor core. SOLUTION: A rotor shaft 5 is supplied with an ATF 10 and extends in the axis Ax direction, and a refrigerant flow which leads to the hollow portion 15 and opens to an outer peripheral surface 5b and is connected to a cooling flow path 8 of a rotor core 4. The entrance 16 is formed. A pair of annular weirs 20 that are arranged on the inner peripheral surface 5a of the rotor shaft 5 at intervals in the axis Ax direction so as to sandwich the refrigerant inlet 16 and that make a round in the circumferential direction while projecting inward in the radial direction and a pair. An axial weir 21 is provided between the annular weirs 20 and extends in the radial direction while projecting inward in the radial direction. [Selection diagram] Fig. 2

Description

  The present invention relates to a rotating electrical machine that supplies liquid refrigerant to a rotor core for cooling.

  A rotor having a hollow rotor shaft to which a rotor core formed with a cooling flow path is fixed, and a refrigerant supply shaft for supplying liquid refrigerant to a hollow portion of the rotor shaft, the cooling flow path of the rotor core and the hollow of the rotor shaft DESCRIPTION OF RELATED ART The rotary electric machine by which the refrigerant | coolant inflow port which connects with the part was formed in the rotor shaft is known (patent document 1).

JP, 2016-146704, A

  The rotary electric machine of Patent Document 1 can guide the liquid refrigerant supplied to the hollow portion of the rotor shaft to the refrigerant inlet by centrifugal force and supply it to the rotor core. However, when the rotor is rotating at low speed, the liquid refrigerant supplied to the hollow portion of the rotor shaft stagnates vertically below the hollow portion due to the lack of centrifugal force, and the supply amount of liquid refrigerant to the rotor core may be reduced. On the other hand, when the rotor rotates at high speed, the side where the flow field of the liquid refrigerant is close to the inner circumferential surface of the rotor shaft may be laminar flow, and the side far from the inner circumferential surface may be turbulent flow. In this case, the liquid refrigerant far from the inner peripheral surface of the rotor shaft may not be properly guided to the refrigerant inlet and may leak from the open end of the rotor shaft to reduce the amount of liquid refrigerant supplied to the rotor core. .

  Then, an object of this invention is to provide the rotary electric machine which can supply suitably the liquid refrigerant supplied to the hollow part of the rotor shaft to a rotor core.

  The rotating electrical machine according to one aspect of the present invention is a rotating electrical machine including a rotor having a rotor core in which a cooling flow channel for guiding liquid refrigerant is formed, and a rotor shaft to which the rotor core is integrally rotatably mounted. The rotor shaft is formed with a hollow portion which is supplied with the liquid refrigerant and extends in the axial direction, and a refrigerant inlet communicating with the hollow portion and opening on the outer peripheral surface and connected to the cooling flow passage of the rotor core A pair of annular projecting portions are disposed on the inner peripheral surface of the rotor shaft at intervals in the axial direction so as to sandwich the refrigerant inlet, and project radially inward while making a round in the circumferential direction, and the pair And an axially extending protrusion extending in the axial direction while protruding radially inward.

Sectional drawing which showed the principal part of the motor generator which concerns on one form of this invention. The expanded sectional view which expanded the cross section regarding the II-II line of FIG. Assembly drawing of a rotor shaft. Sectional drawing which showed the rotor shaft which concerns on a 2nd form. The expanded sectional view which expanded the cross section regarding the VV line | wire of FIG. The figure which showed the structure of the 1st modification. The figure which showed the structure of the 2nd modification. The figure which showed the structure of the 3rd modification. The figure which showed the structure of the 4th modification. The figure which showed the structure of the 5th modification.

(First form)
As shown in FIG. 1, the motor generator 1 is coaxially disposed on the stator 2 fixed to a case (not shown) and the inner periphery of the stator 2 and supported by the case in a rotatable state about the axis Ax. And a rotor 3. The stator 2 includes a coil 2a, and an electric circuit (not shown) is connected to the coil 2a.

  The rotor 3 includes a hollow rotor core 4 in which a plurality of steel plates are stacked, and a rotor shaft 5 to which the rotor core 4 is integrally rotatably mounted while being inserted into the inner periphery of the rotor core 4. In the rotor core 4, a cooling flow passage 11 for guiding an automatic transmission fluid (ATF) 10 is formed. Cooling passage 11 includes a through passage 12 extending in the direction of axis Ax and penetrating through rotor core 4, and an introducing passage 13 extending radially from through passage 12 and opening in inner circumferential surface 4 a of rotor core 4. Although not shown, four introduction paths 13 are arranged at intervals of 90 ° in the circumferential direction.

  As shown in FIGS. 1 and 2, the ATF 10 is supplied to the rotor shaft 5, and a hollow portion 15 extending in the direction of the axis Ax and an inner peripheral surface 5a communicate with the hollow portion 15 and open to the outer peripheral surface 5b 4 One refrigerant inlet 16 is formed. As shown in FIG. 2, the refrigerant inlets 16 are arranged at equal intervals every 90 ° in the circumferential direction. Each refrigerant inlet 16 is connected to the introduction passage 13 of the cooling passage 8 of the rotor core 4. A feed pipe 17 for feeding the ATF 10 is inserted into the hollow portion 15 of the rotor shaft 5. The ATF 10 pressure-fed by the oil pump P is introduced to the supply pipe 17. The ATF 10 led to the supply pipe 17 is supplied to the hollow portion 15 of the rotor shaft 5 by being discharged radially outward from the tip end of the supply pipe 17 as shown by the arrow.

  As shown in FIG. 1 and FIG. 2, on the inner peripheral surface 5 a of the rotor shaft 5, a pair of annular ridges 20 spaced apart in the direction of the axis Ax so as to sandwich the refrigerant inlet 16, and a pair of annular ridges A plurality of (four in this embodiment) axial weirs 21 which are disposed between the two 20 and project radially inward and extend in the direction of the axis Ax are provided. Each annular ridge 20 makes a round in the circumferential direction while projecting radially inward. As shown in FIG. 2, the axial direction ridges 21 are arranged at equal intervals every 90 ° in the circumferential direction. Further, each axial direction ridge 21 has a substantially rectangular cross-sectional shape, and a pair of side surfaces aligned in the circumferential direction are respectively formed by planes orthogonal to the tangential direction.

  As shown in FIG. 3, each axial weir 21 is connected at each end to a pair of annular weirs 20. The pair of annular ridges 20 and the axial ridges 21 constitute an inner sleeve 25 in which they are integrated. By pressing the inner sleeve 25 into the hollow portion 15 of the rotor shaft 5, the pair of annular ridges 20 and the axial ridges 21 are provided on the inner circumferential surface 5 b so as to be integrally rotatable with the rotor shaft 5.

(Effect of the first form)
With the above configuration, when the ATF 10 is supplied to the hollow portion 15 of the rotor shaft 5, the ATF 10 is blocked by the pair of annular wedges 20. As shown in FIG. 2, when the rotor 3 is rotated in the direction of the arrow, the ATFs 10 held by the pair of annular ridges 20 are scraped up by the axial ridges 21 and thus the same direction as the rotation direction of the rotor 3. A rotational force is applied. The ATF 10 to which the rotational force is applied obtains a discharge pressure which is pushed radially outward from each refrigerant inlet 16 by centrifugal force. As a result, the ATF 10 supplied to the hollow portion 15 of the low shaft 5 is led to the cooling flow passage 8 of the rotor core 4 through the respective refrigerant inlets 16 as indicated by the arrows. Therefore, even if the rotational speed of the rotor 3 is low, the ATF 10 can be prevented from stagnating below the rotor shaft 5, so that the decrease in the amount of ATF 10 supplied to the rotor core 4 can be suppressed.

  Further, the ATF 10 is scraped up at each axial direction weir 21 so that the flow velocity distribution of the ATF 10 in the radial direction from the inner peripheral surface 5 a of the rotor shaft 5 is flattened in the range of the projecting height of each axial direction weir 21 . In addition, since the side surface of the axial direction ridge 21 which extends in the direction of the protrusion height and scrapes the ATF is orthogonal to the tangential direction, the flow velocity distribution of the ATF 10 is further flattened in the range of the protrusion height. Therefore, even when the rotational speed of the rotor 3 is high, it is possible to suppress the flow field of the ATF 10 from becoming laminar flow only on the side close to the inner peripheral surface 5 a of the rotor shaft 5 and becoming turbulent flow other than that. Thereby, the flow field of ATF10 becomes a turbulent flow, and it can suppress that ATF10 leaks from the opening end of rotor shaft 5, and the supply of ATF10 to rotor core 4 falls.

(Second form)
Next, the second embodiment will be described with reference to FIGS. 4 and 5. Hereinafter, the description of the configuration common to the first embodiment is omitted. The rotor shaft 30 according to the second embodiment can be replaced with the rotor shaft 5 of the first embodiment. The rotor shaft 30 is formed with a hollow portion 31 to which the ATF 10 is supplied, and four refrigerant inlets 32 communicating with the hollow portion 31 at the inner peripheral surface 30 a and opening at the outer peripheral surface 30 b. The inner circumferential surface 30 a is provided with a pair of annular ridges 33 and four axial ridges 34. Each axial weir 34 is provided integrally with the rotor shaft 30 by machining the inner peripheral surface 30a of the rotor shaft 30 such as broaching. An annular collar 33 configured as an annular component is press-fitted one by one until the end of each axial ridge 34 abuts against the rotor shaft 30 processed in this manner. Thus, the pair of annular ridges 33 is provided on the inner circumferential surface 30 a of the rotor shaft 30 in a state where it can rotate integrally with the rotor shaft 30. The second form can obtain the same effect as the first form, but in particular, it is easy to change the height (protrusion amount) of the pair of annular ridges 33 independently of each axial direction ridge 34 Benefits.

(Modification)
Next, first to fifth modifications in which the axial direction ridge and the like according to the first embodiment are changed will be described with reference to FIGS. In the following description, the same reference numerals as in the first embodiment denote the same parts as in the first embodiment, and a description thereof will be omitted.

  The first modified example shown in FIG. 6 has an axial weir 21A having a lower projecting height than each axial weir 21 according to the first embodiment. According to the first modification, the rotation of the rotor 3 reduces the amount of ATF 10 scraped up in each axial direction weir 21A, and reduces the amount of ATF 10 to which the centrifugal force is applied. Therefore, since the discharge pressure of the ATF 10 is lower than that of the first embodiment, the amount of ATF 10 supplied to the rotor core 4 can be reduced more than that of the first embodiment.

  The 2nd modification shown in Drawing 7 has axial direction ridge 21B whose projection height is higher than each axial direction ridge 21 concerning a 1st form. According to the second modification, the rotation of the rotor 3 increases the amount of ATF 10 scraped up in each axial direction ridge 21B, and increases the amount of ATF 10 to which a centrifugal force is applied. Therefore, since the discharge pressure of the ATF 10 is higher than that of the first embodiment, the amount of ATF 10 supplied to the rotor core 4 can be increased more than that of the first embodiment.

  The third modified example shown in FIG. 8 corresponds to a combination of the first modified example and the second modified example, and two types of axial ridges 21A and 21B of high and low are alternately provided in the circumferential direction. ing. According to the third modification, since the supply amount of the ATF 10 can be changed for each refrigerant inlet 16, precise cooling can be performed.

  The 4th modification shown in Drawing 9 changes the interval of the peripheral direction of axial direction ridge 21 concerning the 1st form. According to the fourth modification, since the amount of ATF 10 existing between the widely spaced axial direction ridges 21 and the amount of ATF 10 existing between the narrowly spaced axial direction ridges 21 are different from each other, these effects are obtained. The centrifugal force is also different. Therefore, the amount of ATF 10 supplied to the refrigerant inlet 16 located between the widely spaced axial weirs 21 is large, and the amount of ATF 10 supplied to the refrigerant inlet 16 located between the closely spaced axial weds 21 is Since the amount of ATF 10 supplied can be changed for each refrigerant inlet 16, for example, it is possible to achieve precise cooling.

  In the fifth modification shown in FIG. 10, the rotor shaft 5 is formed with refrigerant inlets 16 ′ which are close to the axial direction ridges 21 and disposed on both sides of the axial direction ridges 21. According to the fifth modification, the discharge pressure of the ATF 10 can be obtained even when the rotational speed of the rotor 3 is extremely low because the coolant inlet port 16 'approaches the axial weir 21. Further, since the refrigerant inlets 16 'are disposed on both sides of each axial direction ridge 21, even if the rotation direction of the rotor 3 is switched between the normal rotation direction R1 and the reverse rotation direction R2, the discharge condition of the ATF 10 is set in both directions. Can be aligned. Therefore, there is an advantage in applying to a rotating electrical machine for applications in which the rotational direction of the rotor 3 is frequently switched and the rotational speed is extremely low.

(Other modifications)
Each of the above-described embodiments is an embodiment in which the rotary electric machine is implemented as a motor generator, but may be changed to an embodiment in which a motor or a generator is used. Further, the number of axial direction ridges in each of the above-described embodiments is not limited, and the number of axial direction ridges can be changed to a form.

  In each of the above-described embodiments, the axial weir extends in the axial direction and both ends thereof are coupled to each of the pair of annular weirs so that the axial weir and the annular weir are integrated, or both ends of the axial weir are a pair It strikes each of the annular cages. In other words, the axial weir extends axially continuously between the pair of annular weirs. However, it is an example that an axial weir joins or strikes each of a pair of annular weirs. For example, the axial weir can be changed to a form in which only one of the annular weirs is joined or abuts. In addition, the axial weir and the pair of annular weirs may not be coupled or not collided, in other words, it may be changed to a form in which a space is provided between both ends of the axial weir and each of the pair of annular weirs .

  In each of the above-described embodiments, the axial weir extends continuously in the axial direction between the pair of annular weirs. For example, the axial weir extends in the axial direction as a whole, but one of the axial weirs It is also possible to change to a form in which parts or parts are divided.

  In each of the above-described embodiments, the direction in which the axial ridge extends is in the same direction as the axial direction of the rotor shaft, but various forms may be used as long as both ends of the axial ridge are positioned on one side and the other of the axial direction. Can be changed to For example, a configuration in which both ends of the axial ridge are located at one side and the other in the axial direction and extend obliquely with respect to the axial direction, or both ends of the axial ridge are located at the one and the other in the axial direction It is also possible to change it into a form extending obliquely in relation to the axial direction and changing the inclination angle in the opposite direction midway, or in a form extending non-linearly such as bending or meandering in the axial direction.

  Aspects of the present invention derived from each of the above-described embodiment and modification will be described below.

  The rotating electrical machine according to one aspect of the present invention is a rotating electrical machine including a rotor having a rotor core in which a cooling flow channel for guiding liquid refrigerant is formed, and a rotor shaft to which the rotor core is integrally rotatably mounted. The rotor shaft is formed with a hollow portion which is supplied with the liquid refrigerant and extends in the axial direction, and a refrigerant inlet communicating with the hollow portion and opening on the outer peripheral surface and connected to the cooling flow passage of the rotor core A pair of annular projecting portions are disposed on the inner peripheral surface of the rotor shaft at intervals in the axial direction so as to sandwich the refrigerant inlet, and project radially inward while making a round in the circumferential direction, and the pair And an axially extending protrusion extending in the axial direction while protruding radially inward. For example, in each of the above-described embodiments and the above-described modifications, the motor / generator 1, the motor, or the generator corresponds to an example of a rotating electrical machine, the ATF 10 corresponds to an example of a liquid refrigerant, and a pair of annular ridges 20 or a pair The annular ridge 33 corresponds to an example of a pair of annular projections, and the axial ridges 21, 34, 21A, 21B or various axial ridges according to the above-mentioned modification correspond to an example of an axial projection.

  According to the rotating electrical machine of this aspect, when the liquid refrigerant is supplied to the hollow portion of the rotor shaft, the liquid refrigerant is blocked by the pair of annular projecting portions. The liquid refrigerant trapped in the pair of annular projections is scraped up by the axial projections by the rotation of the rotor, so that a rotational force in the same direction as the rotational direction of the rotor is applied. The liquid refrigerant to which the rotational force is applied obtains a discharge pressure which is pushed radially outward from the refrigerant inlet by centrifugal force. Thereby, the liquid refrigerant supplied to the hollow portion of the low shaft is led to the cooling flow passage of the rotor core through the refrigerant inlet. Therefore, even if the rotational speed of the rotor is low, it is possible to prevent the liquid refrigerant from stagnating below the rotor shaft, so it is possible to suppress a decrease in the amount of liquid refrigerant supplied to the rotor core.

  Further, the liquid refrigerant is scraped up at the axially projecting portion, whereby the flow velocity distribution of the liquid refrigerant in the radial direction from the inner peripheral surface of the rotor shaft is flattened within the range of the projecting height of the axially projecting portion. Therefore, even when the rotational speed of the rotor is high, it is possible to suppress the flow field of the liquid refrigerant from becoming laminar flow only on the side close to the inner peripheral surface of the rotor shaft and becoming turbulent flow other than that. As a result, the flow field of the liquid refrigerant becomes turbulent and it can be suppressed that the liquid refrigerant leaks from the open end of the rotor shaft and the supply amount of the liquid refrigerant to the rotor core is reduced.

1 Motor generator (rotary electric machine)
3 Rotor 4 Rotor core 5, 30 Rotor shaft 5a, 30a Inner circumferential surface 5b, 30b Outer circumferential surface 10 ATF (liquid refrigerant)
11 cooling channel 15 hollow portion 16, 32, 16 'refrigerant inlet 20, 33 annular ridge (annular projecting portion)
21, 34, 21A, 21B axial wedges (axial protrusions)

Claims (1)

A rotating electrical machine comprising: a rotor core having a cooling flow path for guiding a liquid refrigerant, and a rotor shaft to which the rotor core is integrally rotatably mounted.
The rotor shaft is formed with a hollow portion which is supplied with the liquid refrigerant and extends in the axial direction, and a refrigerant inlet communicating with the hollow portion and opening on the outer peripheral surface and connected to the cooling flow passage of the rotor core ,
A pair of annular projecting portions are disposed on the inner peripheral surface of the rotor shaft at intervals in the axial direction so as to sandwich the refrigerant inlet, and project radially inward while making a round in the circumferential direction; An electric rotating machine provided between an annular projection and provided with an axial projection extending in the axial direction while projecting inward in the radial direction.

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