Rotating machine

Abstract

The purpose of the present invention is to improve the cooling structure of a rotating machine. A rotating machine according to the present invention comprises: a resolver that measures the rotation angle of a rotor; a resolver chamber that accommodates the resolver at one side in the axial direction of a shaft; a guide part that guides a refrigerant to the resolver chamber; a frame that accommodates a stator and the rotor; and a bracket arranged on one side of the frame in the axial direction. The shaft comprises: a hollow section that extends from an opening section that is open at one side in the axial direction to the other side in the axial direction; and a refrigerant oil passage that penetrates through the shaft from the hollow section to the outside in the radial direction. The shaft is pivotally supported by the bracket via a bearing. The opening section is in communication with the resolver chamber. One end of the shaft in the axial direction penetrates through the bracket from the other side in the axial direction to the one side in the axial direction. The resolver chamber is a space at one side of the bracket in the axial direction. An opening in one side of the resolver chamber in the axial direction is blocked by a sensor cover. Additionally, the guide part includes a through-hole that penetrates through the bracket from the other side in the axial direction to the one side in the axial direction.

Description

Rotating machines

[0001] The present invention relates to a rotating machine.

[0002] Conventionally, rotating machines with cooling structures have been known. Patent Document 1 discloses a structure for cooling the rotor of an electric motor from the inside through a hollow portion of the rotor shaft, which is the rotating shaft of the electric motor. Also, Patent Document 2 discloses a structure having a shaft oil passage provided in the shaft, which is the rotating shaft of a rotating electric machine.

[0003] JP 2021-93869 A Patent No. 6355750 A

[0004] However, conventionally, the oil passages for supplying oil to the rotor shaft or shaft are complicated, requiring separate piping, etc., which hinders downsizing and increases costs due to the additional parts. For this reason, there has been room for improvement in the cooling structure of rotating machines.

[0005] An object of the present invention is to improve the cooling structure of a rotating machine.

[0006] A rotating machine according to one aspect of the present invention includes a stator, a rotor facing the stator across a gap, a shaft that is a rotation axis fixed to the rotor, a resolver that measures a rotation angle of the rotor, a resolver chamber that houses the resolver on one axial side of the shaft, a guide part that guides a refrigerant to the resolver chamber, a frame that houses the stator and the rotor, and a bracket that is arranged on one axial side of the frame, wherein the shaft has a hollow part that extends from an opening that opens on one axial side to the other axial side, and a front and a refrigerant oil passage that penetrates the shaft radially outward from the hollow portion, the shaft is journaled to the bracket via a bearing, the opening is connected to the resolver chamber, one axial end of the shaft penetrates the bracket from the other axial side to the one axial side, the resolver chamber is a space on the one axial side of the bracket, the opening on the one axial side of the resolver chamber is blocked by a sensor cover, and the guide portion includes a through hole that penetrates the bracket from the other axial side to the one axial side.

[0007] In the rotating machine according to one aspect of the present invention, the guide portion includes a flow path formed by a rib provided on the bracket.

[0008] In the rotating machine according to one aspect of the present invention, the refrigerant flows from the other axial side of the bracket to the one axial side via the bearing and is guided to the resolver chamber.

[0009] According to one aspect of the present invention, it is possible to improve the cooling structure of a rotating machine.

[0010] Fig. 2 is a side cross-sectional view of the motor 100 according to the first embodiment of the present invention. Fig. 3 is a perspective view showing a state in which a frame 140 is removed from the motor 100. Fig. 4 is a side view of a bracket 160 as seen from the other axial side.

[0011] Hereinafter, a rotating machine according to an embodiment of the present invention will be described with reference to the drawings. In the drawings, the scale and number of components may differ from the actual structure in order to make each component easier to understand.

[0012] In addition, in the drawings, an XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system as appropriate. In the XYZ coordinate system, the Y axis direction is a direction parallel to the axis of the central axis J shown in Figure 1. The Z axis direction is a radial direction relative to the central axis J, which is the up-down direction in Figure 1. The X axis direction is a direction perpendicular to both the Y axis direction and the Z axis direction. In each of the X axis direction, the side indicated by the arrow in the drawing is the + side, and the opposite side is the - side.

[0013] In the following description, the positive side in the Y-axis direction (+Y side) will be referred to as "one side," and the negative side in the Y-axis direction (-Y side) will be referred to as "the other side." Note that "one side" and "the other side" are names used merely for the purpose of explanation and do not limit the actual positional relationship or direction. Unless otherwise specified, the direction parallel to the central axis J (Y-axis direction) will be referred to simply as "axial direction," the radial direction centered on the central axis J will be referred to simply as "radial direction," and the circumferential direction centered on the central axis J, i.e., around the axis of the central axis J, will be referred to simply as "circumferential direction." In the radial direction, the side closer to the central axis J will be referred to as "radially inner," and the side away from the central axis J will be referred to as "radially outer." In the circumferential direction, the clockwise side when viewed from the +Y side to the -Y side will be referred to as "one circumferential side," and the counterclockwise side will be referred to as "the other circumferential side."

[0014] In this specification, "extending in the axial direction" includes not only extending strictly in the axial direction (Z-axis direction) but also extending in a direction tilted by less than 45° with respect to the axial direction. In addition, in this specification, "extending in the radial direction" includes not only extending strictly in the radial direction, i.e., in a direction perpendicular to the axial direction (Z-axis direction), but also extending in a direction tilted by less than 45° with respect to the radial direction. Furthermore, "parallel" includes not only being strictly parallel but also being tilted by an angle of less than 45° with respect to each other. Furthermore, "extending in a direction perpendicular to the axial direction" includes not only extending in a direction perpendicular to the axial direction (Z-axis direction) but also extending in a direction tilted by less than 45° with respect to the direction perpendicular to the axial direction (Z-axis direction).

[0015] <First Embodiment> Fig. 1 is a perspective view of a motor according to a first embodiment of the present invention. Motor 100 is an example of a rotating machine. Motor 100 has a rotor 110 and a stator 120 disposed radially outward of rotor 110 with a gap therebetween. Motor 100 also has a frame 140 that houses rotor 110 and stator 120, and brackets 150 and 160 provided on both axial ends of frame 140. Frame 140 has a substantially cylindrical shape, bracket 150 is provided to close an opening on the other axial side of frame 140, and bracket 160 is provided to close an opening on one axial side of frame 140.

[0016] Motor 100 has shaft 130, which is a rotating shaft fixed to rotor 110. Shaft 130 is arranged along central axis J. Motor 100 has bearings 171 and 172 that rotatably support shaft 130. Bearing 171 has an outer ring fixed to bracket 150 and an inner ring fixed to shaft 130, thereby supporting shaft 130 on the other axial side of rotor 110. Bearing 172 has an outer ring fixed to bracket 160 and an inner ring fixed to shaft 130, thereby supporting shaft 130 on one axial side of rotor 110.

[0017] The shaft 130 has a hollow portion 130a, which is a hole extending from one axial end to the other axial end. The shaft 130 also has a hollow portion 130b, which is a hole extending from the other axial end of the hollow portion 130a to the other axial end. The hollow portion 130b has a larger diameter than the hollow portion 130a. The other axial end of the hollow portion 130b is not open in the axial direction. The one axial end of the hollow portion 130a is open in the axial direction at an opening 130aa. The shaft 130 has a refrigerant oil passage 130ba that penetrates the shaft 130 radially outward from the hollow portion 130b.

[0018] The bracket 160 has a base 160a that is located axially on one side of one axial end of the shaft 130 and extends radially inward, and a protrusion 160b that protrudes from the base 160a on the other axial side and also extends radially inward. The protrusion 160b has a through-hole 160g that penetrates it in the axial direction. The shaft 130 passes through the through-hole 160g. The bracket 160 has a resolver chamber 306, which is a space that accommodates a resolver 301, radially inward of the base 160a and on one axial side of the through-hole 160g. The opening on one axial side of the resolver chamber 306 is covered by a flat sensor cover 305.

[0019] The motor 100 has a resolver 301 that measures the rotation angle of the rotor 110. The resolver 301 has a resolver stator 302, a resolver rotor 303 arranged radially inside the resolver stator 302, and a resolver fixing portion 304 that fixes the resolver stator 302 to the protrusion 160b of the bracket 160. The resolver rotor 303 is fixed to the shaft 130, and rotates as the shaft 130 rotates. The resolver fixing portion 304 has a through-hole that penetrates in the axial direction at a position that at least partially overlaps in the radial direction with the opening 130aa on one axial side of the hollow portion 130a. As a result, the resolver chamber 306 communicates with the hollow portion 130b of the shaft 130.

[0020] The motor 100 has pipes 201 and 202 (see FIG. 2 ) that supply cooling oil (hereinafter referred to as “refrigerant”) from outside the motor 100. FIG. 2 is a perspective view showing the motor 100 with the frame 140 removed. The motor 100 is disposed so that its axial direction is perpendicular to the vertical direction, and the pipes 201 and 202 are disposed vertically above the shaft 130 and parallel to the axial direction. The refrigerant flows through the pipes 201 and 202 from the other axial side to the one axial side. The pipes 201 and 202 have openings at their ends on the one axial side, and the refrigerant flows out of the pipes 201 and 202 through these openings. Note that the motor 100 may not include the pipes 201 and 202, and an oil passage in place of the pipes 201 and 202 may be formed within the frame 140.

[0021] 3 is a side view of bracket 160 as viewed from the other axial side. Bracket 160 has ribs 160c, 160d, 160e, and 160f protruding from base 160a to the other axial side. Bracket 160 has flow path 161 sandwiched between rib 160c and rib 160e. Bracket 160 has flow path 161 sandwiched between rib 160d and rib 160f. Refrigerant flowing out from the opening at one axial end of pipe 201 flows down flow path 161 formed by rib 160c and rib 160e due to its own weight. Refrigerant flowing out from the opening at one axial end of pipe 202 flows down flow path 162 formed by rib 160d and rib 160f due to its own weight.

[0022] Bracket 160 has through holes 163 and 164 that penetrate bracket 160 from the other axial side to one axial side. Through hole 163 is located downstream of flow path 161, and the refrigerant flowing down flow path 161 on the other axial side of bracket 160 passes through through hole 163 and reaches one axial side of bracket 160. Through hole 164 is located downstream of flow path 162, and the refrigerant flowing down flow path 162 on the other axial side of bracket 160 passes through through hole 163 and reaches one axial side of bracket 160. The side walls of through holes 163 and 164 are tapered so that one axial side is positioned vertically lower than the other axial side, thereby making it easier for the refrigerant flowing down flow paths 161 and 162 to pass through through holes 163 and 164.

[0023] The through holes 163 and 164 communicate with the resolver chamber 306 on one axial side of the bracket 160. The refrigerant that passes through the through holes 163 and 164 and reaches the one axial side of the bracket 160 is stored in the resolver chamber 306.

[0024] The refrigerant flowing out from the openings at the ends of the pipes 201 and 202 on one side in the axial direction can also reach the resolver chamber 306 via a route passing through the bearing 172 .

[0025] An inverter (not shown) that drives the motor 100 is arranged on one axial side of the resolver chamber 306 in the bracket 160, but by blocking one axial side of the resolver chamber 306 with a sensor cover 305, the refrigerant stored in the resolver chamber 306 is prevented from leaking to the inverter side.

[0026] The refrigerant stored in the resolver chamber 306 reaches the hollow portion 130b through the through hole of the resolver fixing portion 304 and the opening 130aa of the shaft 130. When the rotor 110 rotates, the refrigerant in the hollow portion 130b is sprayed radially outward of the shaft 130 through the refrigerant oil passage 130ba by centrifugal force, thereby cooling the rotor 110.

[0027] The resolver chamber 306 may have only the hollow portion 130b as a destination for the refrigerant in the resolver chamber 306, or may have a discharge hole on the vertically lower side that discharges the refrigerant in the resolver chamber 306 to the outside. In this case, by setting the amount of refrigerant discharged from the discharge hole to be less than the amount of refrigerant supplied to the resolver chamber 306, it is possible to ensure that the refrigerant is supplied to the hollow portion 130b.

[0028] The ribs 160 c , 160 d , 160 e , and 160 f of the bracket 160 , and the through holes 163 and 164 function as guide portions that guide the refrigerant to the resolver chamber 306 .

[0029] According to this embodiment, the refrigerant can be supplied to the hollow portion 130b of the shaft 130 from the resolver chamber 306 that has been provided conventionally, and no new configuration is required to supply the refrigerant to the shaft 130, so this does not hinder size reduction and also reduces costs.

[0030] The present invention is not limited to the above-described embodiments, and various improvements and design changes may be made without departing from the spirit of the present invention. In addition, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0031] This application claims priority based on Japanese Patent Application No. 2024-043218, filed on March 19, 2024, and incorporates by reference all the contents of said Japanese Patent Application.

[0032] REFERENCE SIGNS LIST 100...motor, 110...rotor, 120...stator, 130...shaft, 130a...hollow portion, 130aa...opening, 130b...hollow portion, 140...frame, 150...bracket, 160...bracket, 301...resolver, 306...resolver chamber

Claims

1. A device comprising: a stator; a rotor facing the stator across a gap; a shaft that is a rotating shaft fixed to the rotor; a resolver that measures the rotation angle of the rotor; a resolver chamber that houses the resolver on one axial side of the shaft; a guide portion that guides refrigerant to the resolver chamber; a frame that houses the stator and the rotor; and a bracket that is arranged on one axial side of the frame, wherein the shaft has a hollow portion that extends from an opening that opens on one axial side to the other axial side, and a refrigerant oil passage that passes through the shaft radially outward from the hollow portion, the shaft is journaled by the bracket via a bearing, the opening is in communication with the resolver chamber, and the one axial end of the shaft passes through the bracket from the other axial side to one axial side, the resolver chamber is a space on one axial side of the bracket, and the opening on one axial side of the resolver chamber is closed by a sensor cover, the guide portion includes a through-hole that passes through the bracket from the other axial side to the one axial side.

2. The rotating machine according to claim 1, wherein the guide portion includes a flow path formed by a rib provided on the bracket.

3. A rotating machine according to claim 1, characterized in that the refrigerant flows from the other axial side of the bracket to the one axial side via the bearing and is introduced into the resolver chamber.

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