JP2023024031A - Rotary machine - Google Patents

Abstract

To provide a motor in which a rotor can be better cooled.SOLUTION: A motor 1 includes a rotatable rotor 2, a stator 3 covering the outer peripheral surface of the rotor 2 with a gap, and a housing 52 that accommodates the rotor 2 and the stator 3 in its own accommodation space 52a. A shaft 55 has a shaft oil passage 55a. The rotor 2 includes a core oil passage 2a. The housing 52 includes a liquid passage 54. The shaft oil passage 55a of the shaft 55 and the core oil passage 2a of the rotor 2 communicate with each other and do not communicate with the liquid passage 54 of the housing 52 directly or indirectly.SELECTED DRAWING: Figure 1

Description

The present invention relates to rotating machines such as motors.

2. Description of the Related Art Conventionally, a rotating machine is known that includes a rotatable rotor, a stator that covers the outer peripheral surface of the rotor with a gap therebetween, and a housing that accommodates the rotor and the stator, and the housing includes a coolant flow path through which coolant flows. .

For example, a rotating electrical machine as a rotating machine described in Patent Document 1 includes a cooling pipe as a coolant flow path extending spirally in a cylindrical frame as a housing that accommodates a rotor and a stator. The coolant that has flowed into the cooling pipe from one end of the cooling pipe flows along the helical path and is then discharged to the outside from the other end of the cooling pipe. A stator, which is placed inside the tubular frame, is directly fixed to the frame.

JP 2019-213350 A

In the rotating electric machine having such a configuration, the stator is directly fixed to the frame, and thus cooled by the coolant through the frame and the cooling pipe. However, the rotor arranged inside the stator is not connected to the stator, and air with low thermal conductivity is present in the gap between the rotor and the stator. Therefore, the efficiency of cooling the rotor by the refrigerant in the cooling pipes arranged in the frame is low, and there is a possibility that the rotor cannot be sufficiently cooled.

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and an object of the present invention is to provide a rotating machine capable of cooling the rotor better.

One aspect of the present invention includes a rotatable rotor, a stator that covers the outer peripheral surface of the rotor with a gap therebetween, and a housing that accommodates the rotor and the stator in its own accommodation space, wherein the housing: A rotating machine comprising a coolant flow path through which a coolant flows, comprising a shaft penetrating the rotor and rotating together with the rotor, wherein each of the shaft and the rotor has a coolant flow path through which the coolant flows, and the shaft and the coolant flow path of the rotor communicate with each other, and do not directly or indirectly communicate with the coolant flow path of the housing.

ADVANTAGE OF THE INVENTION According to this invention, there exists an outstanding effect that a rotor can be cooled more favorably.

1 is a vertical cross-sectional view showing essential parts of a motor according to an embodiment; FIG. It is a diagram. It is a longitudinal cross-sectional view showing a housing of the same motor. FIG. 4 is an exploded view of the housing; FIG. 2 is a transverse cross-sectional view showing the X1-X1′ cross section in FIG. 1 of the same housing; FIG. 2 is a cross-sectional view showing the X2-X2' section of the same housing in FIG. 1; FIG. 2 is a cross-sectional view of the same housing taken along the line X3-X3′ in FIG. 1; and FIG. 9 is an exploded perspective view showing a housing of a motor according to a modification.

An embodiment of a motor as a rotating machine to which the present invention is applied will be described below with reference to the drawings.
In order to facilitate the understanding of the description in the embodiments, structures and elements other than the main part of the present invention will be described with simplification or omission. Moreover, in each figure, the same code|symbol is attached|subjected to the same element. It should be noted that the shape, dimensions, etc. of each element shown in each drawing are schematically shown, and do not represent the actual shape, dimensions, etc.

First, the basic configuration of the motor according to the embodiment will be described. FIG. 1 is a vertical cross-sectional view showing essential parts of a motor 1 according to an embodiment. 1, for the sake of convenience, illustration of a part of an oil passage 53 and a part of a liquid passage 54 provided in the housing 52, which will be described later, is omitted.

The motor 1 is an inner rotor type motor, and includes a cylindrical housing 52, a shaft 55, a rotor (rotor) 2, a stator (stator) 3, an electric oil pump 61, an oil cooler 62, an electric coolant pump 63, and a coolant cooler 64 . The rotor 2 is an embedded magnet rotor. The motor 1 is an interior permanent magnet synchronous motor (IPMSM), such as a vehicle motor, which requires high power density. As the motor 1, SPM (surface permanent magnetic)

The axial shaft 55 passes through the cylindrical rotor 2 along the direction of the rotation axis A of the rotor 2 (hereinafter simply referred to as the axial direction) and is positioned on the rotation axis A. As shown in FIG. The shaft 55 is rotationally driven around the rotational axis A together with the rotor 2 . The cylindrical housing 52 has an accommodation space 52 a that accommodates the rotor 2 , stator 3 and shaft 55 . The housing 52 also serves as a yoke and holds the cylindrical stator 3 on its inner peripheral surface. The rotor 2 is housed inside the hollow of the stator 3 .

A stator 3 is arranged on the outer peripheral side of the rotor 2 with an air gap therebetween. That is, the hollow stator 3 includes the rotor 2 in the hollow. The motor 1 rotates the rotor 2 around the rotation axis A by sequentially switching the magnetic field of the stator 3 by controlling the current of the coil to generate an attractive force or a repulsive force with the magnetic field of the rotor 2 .

The rotor 2 has a rotor core and a plurality of permanent magnets. The rotor core of the rotor 2 is, for example, a cylindrical member formed by stacking stamped silicon steel plates in the axial direction. An insulating adhesive is interposed between the individual silicon steel plates forming the rotor core, and the individual silicon steel plates are insulated from each other. A shaft 55 is fitted along the rotation axis A into a hollow formed in the axial center portion of the rotor core. In the motor 1, the shaft 55 is rotatably supported by bearings (not shown).

The stator 3 has a stator core. A plurality of teeth protruding inward in a radial direction centered on the rotation axis A (hereinafter simply referred to as a radial direction) are arranged on the inner peripheral surface side of the cylindrical stator core. The respective teeth are arranged at regular intervals in the circumferential direction centered on the rotation axis A (hereinafter simply referred to as the circumferential direction). The spaces between adjacent teeth each form a slot. A coil is wound around the slot.

The motor 1 is designed on the premise that it is arranged in a posture in which the rotation axis A is parallel to the horizontal direction as shown in the drawing. Hereinafter, the posture described above will be referred to as a normal posture. In the figure, the dashed-dotted line labeled Tp (Top) indicates the vertex position of the motor 1 installed in the normal posture. A dashed-dotted line labeled BL (Bottom point) indicates the bottom position of the motor 1 installed in the normal posture.

Next, a characteristic configuration of the motor 1 according to the embodiment will be described.
The housing 52 has an oil passage 53 and a liquid passage 54 . Each of the oil passage 53 and the liquid passage 54 is hollow and functions as a refrigerant passage. Cooling oil as a coolant flows through the oil passage 53 . In addition, a cooling liquid as a coolant flows through the liquid path 54 .

The oil passage 53 includes a first oil passage 53a, a second oil passage 53b, a third oil passage 53c, a fourth oil passage 53d, and a fifth oil passage 54e. The first oil passage 53a is arranged in the vicinity of the vertex Tp of the housing 52 so as to extend in the axial direction. The second oil passage 53b communicates with the axial front side (F side) end of the first oil passage 53a and extends radially inward from the outer side. The third oil passage 53c communicates with the radially inner end of the second oil passage 53b, and extends from the front side to the rear side (R side) in the axial direction. The fifth oil passage 54e is a flow passage provided in the rear wall of the housing 52 and communicating between the housing space 52a and the outside. The fourth oil passage 53d will be detailed later.

The fluid path 54 includes a first fluid path 54a, a second fluid path 54b, and a third fluid path 54c. A first fluid passage 54 is provided at the upper end of the front wall of the housing 52 and extends axially. The third liquid passage 54c is provided at the upper end of the rear wall of the housing 52 and extends in the axial direction. The second liquid path 54b will be detailed later.

The shaft 55 is provided with a shaft oil passage 55a as a refrigerant passage extending axially at the position of the rotation axis A. As shown in FIG. The axial front end of the shaft oil passage 55 a communicates with the axial rear end of the third oil passage 52 c of the housing 52 .

A rotor core of the rotor 2 includes six core oil passages 2a. The six core oil passages 2a are arranged at positions shifted by 60[°] from each other in the circumferential direction, as shown in FIG. 4 which will be described later. The axial rear end of each core oil passage 2 a communicates with the axial rear end of the shaft oil passage 55 a of the shaft 55 . Each of the six core oil passages 2a has a first outlet 2a1 and a second outlet 2a2. The first discharge port 2a1 is arranged at the rear-side end in the axial direction of the core oil passage 2a and faces radially outward. Further, the second discharge port 2a2 is arranged at the end of the core oil passage 2a on the front side in the axial direction and faces the front side in the axial direction.

The electric oil pump 61 discharges cooling oil as a refrigerant. The cooling oil discharged from the electric oil pump 61 is cooled through the oil cooler 62 and then flows into the first oil passage 53 a of the housing 52 . After that, the cooling oil flows into the shaft oil passage 55 a of the shaft 55 after passing through the second oil passage 53 b and the third oil passage 53 c of the housing 52 . In the shaft oil passage 55 a , the cooling oil flows axially from the front side toward the rear side, and then splits into six core oil passages 2 a in the rotor core of the rotor 2 .

The cooling oil that has flowed from the shaft oil passage 55a of the shaft 55 into the core oil passage 2a of the rotor core of the rotor 2 is split into one that flows toward the first discharge port 2a1 and one that flows toward the second discharge port 2a2. . The cooling oil flowing toward the first discharge port 2a1 is discharged from the first discharge port 2a1 and scatters radially outward from the inside of the housing space 52a. In addition, the cooling oil flowing toward the second discharge port 2a2 is discharged from the second discharge port 2a2 after flowing in the core oil passage 2a from the rear side toward the front side along the axial direction. It scatters in 52a toward the front side from the rear side. After that, the aforementioned cooling oil accumulates at the bottom of the housing space 52a.

The electric coolant pump 63 discharges coolant as a coolant. The cooling liquid discharged from the electric cooling liquid pump 63 flows into the first liquid passage 54 a of the housing 52 after being cooled through the cooling liquid cooler 64 . After that, the cooling liquid is sucked into the electric cooling liquid pump 63 after passing through the second liquid passage 54b and the third liquid passage 54c.

FIG. 2 is a longitudinal sectional view showing the housing 52. As shown in FIG. The housing 52 includes an oil storage portion 59 that stores cooling oil. The oil storage portion 59 is arranged in the cylindrical portion of the housing 52 and opens toward the upper portion of the rear end portion of the entire area of the housing space 52a.

The fourth oil passage 53d of the housing 52 has a semi-helical structure. A rear-side end of the fourth oil passage 53 d communicates with the oil reservoir 59 . In addition, the fourth oil passage 53d has a first oil passage reversal portion 53d1 that reverses from the upward posture to the downward posture regardless of the spiral structure, and the upward posture to the downward posture regardless of the spiral structure. It is provided with the oil passage 2nd reversal part 53d2 which reverses. The second oil passage reversal portion 53d2 is arranged closer to the front side than the first oil passage reversal portion 53d1. In the fourth oil passage 53d, the cooling oil relatively flows from the rear side toward the front side.

The oil storage portion 59 is located above the first oil passage reversing portion 53d1 of the fourth oil passage 53d. Further, the first oil passage reversal portion 53d1 of the fourth oil passage 53d is located above the second oil passage reversal portion 53d2. During operation of the motor 1, the cooling oil stored in the oil storage portion 59 flows into the fourth oil passage 53d due to gravity. After that, the cooling oil flows along the semi-spiral path due to gravity, and then reverses the flow direction at the first oil passage reversing portion 53d1 regardless of the semi-spiral structure. Further, the cooling oil flows along a semi-spiral path in the front side region of the fourth oil passage 53d due to gravity, and then changes the direction of flow in the second oil passage reversal portion 53d2 to the semi-spiral structure. Flip regardless. Due to such behavior, the cooling oil flows relatively from the rear side toward the front side in the fourth oil passage 53d.

When the motor 1 is not in operation, all the cooling oil in the oil reservoir 59 flows into the fourth oil passage 53d and the oil reservoir 59 becomes empty. Further, in the fourth oil passage 53d when the motor 1 is not in operation, the cooling oil is stored only in the area below the second oil passage reversing portion 53d2.

The second liquid passage 54b of the housing 52 has a spiral structure. The front-side end of the second fluid path 54b communicates with the first fluid path 54a. In addition, the second liquid path 54b has a first liquid path reversing portion 54b1 that reverses from the upward posture to the downward posture regardless of the spiral structure, and the upward posture to the downward posture regardless of the spiral structure. and a liquid path second reversing portion 54b2 that reverses. The second liquid path reversing portion 54b2 is arranged on the front side of the first liquid path reversing portion 54b1. In the second liquid passage 54b, the liquid discharge pressure of the electric coolant pump 63 causes the coolant to flow relatively from the front side toward the rear side.

The first oil passage reversal portion 53d1 of the fourth oil passage 53d and the second liquid passage reversal portion 54b2 of the second liquid passage 54b are arranged at the same position in the axial direction. It is arranged above the liquid path second reversing portion 54b2. Further, the second oil passage reversal portion 53d2 of the fourth oil passage 53d and the first liquid passage reversal portion 54b1 of the second liquid passage 54b are arranged at the same position in the axial direction. is arranged above the first liquid path reversing portion 54b1.

3 is an exploded view of the housing 52. FIG. This development view shows a state in which the housing 52 is cut at the position of the vertex Tp and spread. As shown, the semi-spiral fourth oil passage 53d and the spiral second fluid passage 54b are not connected to each other and are independent.

4 is a cross-sectional view showing the X1-X1' section of the housing 52 in FIG. A part of the cooling oil discharged from the first discharge port 2 a 1 of the core oil passage 2 a of the rotor 2 flows into the oil reservoir 59 through the opening of the oil reservoir 59 of the housing 52 . After that, the cooling oil flows from the oil reservoir 59 into the fourth oil passage 53d by gravity, and then follows the semi-spiral path of the fourth oil passage 53d to reach the inside of the first oil passage reversing portion 53d1. Inside the first oil passage reversal portion 53d1, the cooling oil stored in the oil reservoir 59 located above the first oil passage reversal portion 53d1 receives pressure due to its own weight, and the first oil passage reversal portion 53d1 is opened. Reverse the flow inside.

FIG. 5 is a cross-sectional view of the housing 52 taken along line X2-X2' in FIG. The first oil passage reversal portion 53d1 of the fourth oil passage 53d is located higher than the second oil passage reversal portion (53d2 in FIG. 2) and the terminal opening (53d3 in FIG. 6) of the fourth oil passage 53d. For this reason, the cooling oil in the first oil passage reversing portion 53d1 has a pressure due to the weight of the cooling oil stored in the oil reservoir (55) and the weight of the cooling oil in the first oil passage reversing portion 53d1. Due to synergism, it follows a semi-helical path as shown.

FIG. 6 is a cross-sectional view showing the X3-X3' section of the housing 52 in FIG. 53 d of 4th oil paths are equipped with terminal opening 53d3 in the terminal position of a cooling oil flow direction. The end opening 53d3 is positioned at the lowest portion of the fourth oil passage 53d. At the end portion of the fourth oil passage 53d, the pressure due to the weight of the cooling oil existing above the end opening 53d3 on the upstream side of the end opening 53d3 causes the cooling oil to flow from the end opening into the housing space (52 in FIG. 1). flow out to The cooling oil that has flowed out is stored in the lower portion of the accommodation space 52a shown in FIG. 1 and is sucked into the electric oil pump 61 through the fifth oil passage 53e.

The shaft oil passage 55 a of the shaft 55 and the core oil passage 2 a of the rotor 2 communicate with each other, and do not communicate directly or indirectly with the liquid passage 54 of the housing 52 . In such a configuration, the coolant flowing through the liquid passage 54 of the housing 52 directly cools the housing 52 and indirectly cools the stator 3 fixed to the housing 52 . In addition, the shaft 55 and the rotor 2 are directly cooled by the cooling oil that flows through the shaft oil passage 55a and the core oil passage 2a that are completely independent of the liquid passage 54 . As a result, the rotor 2 can be cooled better than in the conventional configuration.

Next, a modified example of the motor 1 will be described. Note that the configuration of the motor 1 according to the modification is the same as that of the embodiment unless otherwise specified.

FIG. 7 is an exploded perspective view showing the housing 52 of the motor 1 according to the modification. The housing 52 has a first groove 57 and a second groove 58 on its inner peripheral surface. Each of the first groove 57 and the second groove 58 extends in the axial direction. The first oil passage reversing portion 53d1 of the fourth oil passage (53d in FIG. 2) opens radially inward. In addition, the oil passage second reversal portion 53d2 of the fourth oil passage also opens radially inward. The first groove 57 starts from a position immediately below the oil reservoir 59 in the axial direction and connects to the opening of the first oil passage reversal portion 53d1. Also, the second groove 58 starts from a position immediately below the oil reservoir 59 in the axial direction and connects to the opening of the second oil passage reversal portion 53d2.

The motor 1 according to the modification is arranged in a posture in which the axial direction is slightly inclined from the horizontal direction. The housing 52 takes a posture with a slight downward slope from the rear side to the front side.

Some of the cooling oil discharged from the six first discharge ports (2a1 in FIG. 1) of the rotor (2 in FIG. 1) flows into the rear-side ends of the first grooves 57 or the second grooves 58 in the axial direction. flow in. Then, it flows downward along the inside of the first groove 57 or the second groove 58 and flows into the first oil passage reversal portion 53d1 or the second oil passage reversal portion 53d2.

Although an example in which the present invention is applied to the motor 1 as a rotating machine has been described, the present invention may be applied to a generator (dynamo) as a rotating machine.

The present invention is not limited to the above-described embodiment and modifications, and a configuration different from the embodiment can be adopted within the scope to which the configuration of the present invention can be applied. The present invention provides unique effects for each of the aspects described below.

[First aspect]
A first mode includes a rotatable rotor (for example, rotor 2), a stator (for example, stator 3) covering the outer peripheral surface of the rotor through a gap, and an accommodation space (for example, accommodation space 52a) for the rotor and the stator. ) and a housing (e.g., housing 52) to be housed in a rotating machine (e.g., motor 1) provided with a coolant flow path through which a coolant flows. A shaft (e.g., shaft 55) is provided, and each of the shaft and the rotor includes a coolant flow path through which a coolant flows. core oil passages 2a) communicate with each other, and do not directly or indirectly communicate with the coolant passages (for example liquid passages 54) of the housing.

In such a configuration, the coolant flowing through the coolant channel of the housing directly cools the housing and indirectly cools the stator fixed to the housing. In addition, the shaft and rotor are directly cooled by coolant flowing in the shaft coolant flow path and the rotor coolant flow path, completely independent of the housing coolant flow path. As a result, the rotor can be cooled better than in the conventional configuration.

[Second aspect]
A second aspect is the rotary machine according to the first aspect, wherein the refrigerant flow path (eg, core oil path 2a) of the rotor includes a discharge port (eg, first discharge port 2a1) directed outward in the radial direction. It is characterized by

With such a configuration, the housing can be cooled from the inner peripheral surface side by causing the coolant discharged from the outlet of the coolant flow path of the rotor to adhere to the inner peripheral surface of the housing.

[Third aspect]
A third aspect is the rotary machine according to the second aspect, wherein the housing is a first system refrigerant flow path as a refrigerant flow path that communicates with neither the refrigerant flow path of the shaft nor the refrigerant flow path of the rotor. (for example, the liquid path 54), and a second system refrigerant flow path (for example, a fourth oil path 53d) independent of the first system refrigerant flow path.

In such a configuration, the housing is cooled from the inside by the refrigerant flowing through the first system refrigerant flow path, and the housing is also cooled from the inside by the refrigerant flowing through the second system refrigerant flow path that is completely independent of the first system refrigerant flow path. Cooling. Thereby, the cooling efficiency of the housing can be further enhanced.

[Fourth aspect]
A fourth aspect is the rotary machine according to the third aspect, wherein a refrigerant reservoir (e.g., an oil reservoir) communicates with the second system refrigerant flow path above the second system refrigerant flow path and stores the refrigerant. 59), wherein the refrigerant reservoir has an opening facing radially inward and receives the refrigerant discharged from the discharge port of the rotor, and the second system refrigerant flow path extends from the refrigerant reservoir is arranged below.

In such a configuration, the refrigerant discharged from the rotor outlet is stored in the refrigerant reservoir. Then, the refrigerant stored in the refrigerant reservoir can flow into the second system refrigerant flow channel by the principle of siphon.

[Fifth aspect]
A fifth aspect is the rotating machine of the fourth aspect, wherein the second system refrigerant flow path has a terminal opening ( For example, a terminal opening 53d3) is provided, and the terminal opening is positioned at the bottom of the second system refrigerant flow path.

[Sixth aspect]
With such a configuration, the refrigerant stored in the refrigerant reservoir can flow from the inlet of the second system refrigerant flow path to the end flow path by the siphon principle.

The present invention can be applied to rotating machines such as motors and dynamos.

DESCRIPTION OF SYMBOLS 1... Motor (rotating machine) 2... Rotor 2a... Core oil passage (refrigerant flow path of rotor) 2a1... First discharge port (discharge port) 3... Stator, 52...Housing 52a...Accommodating space 53...Oil path 53d...Fourth oil path (second system refrigerant flow path) 53d3...End opening 54...Liquid path (First system refrigerant flow path) 55... Shaft 55a... Shaft oil path 59... Oil reservoir (refrigerant reservoir)

Claims (5)

A rotatable rotor, a stator that covers the outer peripheral surface of the rotor with a gap therebetween, and a housing that accommodates the rotor and the stator in its own accommodation space, wherein the housing defines a coolant flow path through which coolant flows. A rotating machine comprising
A shaft penetrating the rotor and rotating together with the rotor,
each of the shaft and the rotor includes a coolant channel through which a coolant flows;
the coolant flow path of the shaft and the coolant flow path of the rotor communicate with each other and do not directly or indirectly communicate with the coolant flow path of the housing;
A rotating machine characterized by: The rotating machine according to claim 1,
wherein the coolant channel of the rotor includes a discharge port facing radially outward;
A rotating machine characterized by: The rotating machine according to claim 2,
In addition to a first system refrigerant flow path as a refrigerant flow path that communicates with neither the shaft refrigerant flow path nor the rotor refrigerant flow path, the housing has a first system refrigerant flow path that is independent of the first system refrigerant flow path. Equipped with two refrigerant flow paths,
A rotating machine characterized by: A rotating machine according to claim 3,
a refrigerant reservoir that is above the second system refrigerant flow path and communicates with the second system refrigerant flow path and that stores the refrigerant;
the coolant reservoir has an opening facing radially inward for receiving the coolant discharged from the discharge port of the rotor;
The second system refrigerant flow path is arranged below the refrigerant reservoir,
A rotating machine characterized by: The rotating machine according to claim 4,
wherein the second system refrigerant flow path has a terminal opening through which the refrigerant flows out into the housing space at the end of the second system refrigerant flow path in the refrigerant flow direction,
The terminal opening is located at the lowest part in the second system refrigerant flow path,
A rotating machine characterized by:

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