Rotary electric machine

Abstract

A rotary electric machine according to the present invention comprises: a terminal holding member that holds a terminal of a circuit which supplies power to a coil of the rotary electric machine; and a refrigerant tank that is integrally formed with the terminal holding member, has a storage part which temporarily stores a refrigerant for cooling the rotary electric machine, and that allows the refrigerant to flow downward from a through hole formed in the bottom of the storage part.

Description

Rotating electric machines

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

[0002] Rotating electric machines, such as motors and generators, can sometimes be difficult to operate efficiently due to heat generated by coils during operation. For this reason, technologies for cooling the interior of rotating electric machines have been developed. One example of such a technology is the rotating electric machine disclosed in Patent Document 1. This rotating electric machine includes a coolant tank on the peripheral wall at the top of the coil end portion, which stores coolant for cooling the coil end portion. The coolant tank includes a coolant reservoir for storing the supplied coolant and at least two coolant supply ports connected to the coolant reservoir for distributing and supplying the coolant from the top side of the coil end portion to the peripheral wall on both sides of the coil end portion. Furthermore, rotating electric machines generally include a terminal holding member for holding terminals of a circuit that supplies power to the coil.

[0003] Japanese Patent Application Laid-Open No. 2005-229672

[0004] However, the rotating electric machine described above includes a coolant tank and a terminal holder that are independent of each other. Therefore, the rotating electric machine described above requires both a structure, components, etc. for installing the coolant tank and a structure, components, etc. for installing the terminal holder. Therefore, the rotating electric machine described above is difficult to miniaturize, and the manufacturing costs increase, which can make it difficult to manufacture.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a rotating electric machine that can be easily miniaturized, that can reduce the cost required for manufacturing, and that can be easily manufactured.

[0006] In order to solve the above-mentioned problems, the rotating electric machine of the present invention comprises a terminal holding member that holds terminals of a circuit that supplies power to the coil of the rotating electric machine, and a refrigerant tank that is formed integrally with the terminal holding member and has a storage section that temporarily stores a refrigerant that cools the rotating electric machine, and that flows the refrigerant downward through a through hole formed in the bottom of the storage section.

[0007] According to the present invention, it is possible to provide a rotating electric machine that can be easily miniaturized, the cost required for manufacturing can be reduced, and manufacturing can be facilitated.

[0008] 1A and 1B are diagrams illustrating examples of a stator, a terminal holding member, a refrigerant tank, a refrigerant discharge pipe, etc. of a motor according to an embodiment; FIG. 2A is a diagram illustrating examples of a refrigerant tank, a refrigerant discharge pipe, and the surrounding structure of these two according to an embodiment; and FIG. 3A is a diagram illustrating examples of a terminal holding member and a refrigerant tank according to an embodiment.

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a motor will be used as an example of a rotating electric machine. This motor is mounted on an electric vehicle to rotate the wheels of the electric vehicle, for example. In addition, in the description of this embodiment, an X-axis parallel to a rotation axis A of the motor (described later), a Y-axis perpendicular to the X-axis, and a Z-axis perpendicular to the X-axis and Y-axis are used. The X-axis, Y-axis, and Z-axis form a right-handed system. The Z-axis is parallel to the direction in which gravity is applied.

[0010] Fig. 1 is a diagram showing examples of a stator, terminal holding member, refrigerant tank, refrigerant discharge pipe, etc. of a motor according to an embodiment. Fig. 2 is a diagram showing examples of a refrigerant tank, a refrigerant discharge pipe, and the surrounding structure of these two components according to an embodiment. As shown in Figs. 1 and 2 , the motor according to an embodiment includes a stator 1, terminals 41, 42, 43, 44, bus bars 51, 52, 53, and 54. Also, as shown in Figs. 1 and 2 , the motor includes a terminal holding member 6, a refrigerant tank 7, a refrigerant discharge pipe 81, and a refrigerant discharge pipe 82.

[0011] As shown in Figures 1 and 2, the stator 1 includes a stator core 11 and a coil 12. The stator core 11 is a cylindrical member into which the rotor 2 and the shaft 3 are inserted. The stator core 11 is fastened to a housing (not shown) of the motor by bolts 111, 112, 113, and 114. The rotor 2 is a cylindrical member that rotates around a rotation axis A that is parallel to the X-axis. The shaft 3 is a rod-shaped member that supports the rotor 2 in a manner that allows the rotor 2 to rotate around the rotation axis A. The stator core 11 has a plurality of teeth formed on its inside.

[0012] The coil 12 includes a U-phase winding 121, a V-phase winding 122, and a W-phase winding 123. The windings 121, 122, and 123 are all copper wires wound around the teeth. The windings 121, 122, and 123 are star-connected. When a three-phase AC current is supplied to the coil 12, it generates a magnetic force that rotates the rotor 2.

[0013] Terminal 41 is a U-phase terminal of the circuit that supplies three-phase AC to coil 12. Terminal 41 is electrically connected to winding 121 and is a terminal for supplying U-phase power of the three-phase AC to winding 121. Terminal 42 is a V-phase terminal of the circuit that supplies three-phase AC to coil 12. Terminal 42 is electrically connected to winding 122 and is a terminal for supplying V-phase power of the three-phase AC to winding 122. Terminal 43 is a W-phase terminal of the circuit that supplies three-phase AC to coil 12. Terminal 43 is electrically connected to winding 123 and is a terminal for supplying W-phase power of the three-phase AC to winding 123. Terminal 44 is a terminal at the neutral point of star-connected windings 121, 122, and 123.

[0014] The bus bar 51 is a conductor that electrically connects the winding 121 to the terminal 41. The bus bar 52 is a conductor that electrically connects the winding 122 to the terminal 42. The bus bar 53 is a conductor that electrically connects the winding 123 to the terminal 43. The bus bar 54 is a conductor that electrically connects the winding 121, the winding 122, and the winding 123 to the terminal 44.

[0015] 3 is a diagram showing an example of a terminal holding member and a refrigerant tank according to an embodiment. As shown in FIG. 3, the terminal holding member 6 and the refrigerant tank 7 are integrally formed. For example, the terminal holding member 6 and the refrigerant tank 7 are integrally formed by insert molding, which is performed with the bus bars 51, 52, and 53 housed in an injection molding die. Alternatively, the terminal holding member 6 and the refrigerant tank 7 may be integrally formed by resin injection molding.

[0016] 2, the terminal holding member 6 and the refrigerant tank 7 are disposed on the +Z direction side of the portion of the coil 12 that is not covered by the stator core 11. The terminal holding member 6 is a member that holds terminals 41, 42, and 43 of a circuit that supplies three-phase AC power to the coil 12. The refrigerant tank 7 is disposed on the +Z direction side of the stator 1, as shown in FIGS. 1 and 2. The refrigerant tank 7 also includes a storage portion 71, a recessed portion 72, and through holes 721, 722, and 723, as shown in FIGS. 2 and 3.

[0017] The storage portion 71 is a recess in which the refrigerant discharged from the refrigerant discharge pipe 81 or the refrigerant discharge pipe 82 is temporarily stored. The storage portion 71 has a constant depth except for a portion where the recess portion 72 is formed. The recess portion 72 is a long, narrow recess formed in the Y direction at the bottom of the storage portion 71. The recess portion 72 has a constant depth except for a portion where the through hole 721, the through hole 722, or the through hole 723 is formed. The through hole 721, the through hole 722, and the through hole 723 are all cylindrical holes that penetrate the bottom of the recess portion 72. The through hole 721, the through hole 722, and the through hole 723 are all formed to cool the coil 12, the bus bar 54, etc. by flowing the refrigerant temporarily stored in the storage portion 71 downward.

[0018] As shown in FIGS. 1 and 2 , the refrigerant discharge pipe 81 and the refrigerant discharge pipe 82 are both arranged parallel to the X direction and are pipes through which a refrigerant flows. Each of the refrigerant discharge pipes 81 and 82 has at least one hole formed therein for discharging the refrigerant that cools the motor into the storage section 71. The position, shape, dimensions, etc. of this hole are not particularly limited as long as it is possible to discharge the refrigerant into the storage section 71. Furthermore, the refrigerant flowing through the refrigerant discharge pipe 81 or the refrigerant discharge pipe 82 is discharged from the hole and a pressure necessary for the refrigerant to be stored in the storage section 71 is applied by a pump. Furthermore, because each of the refrigerant discharge pipes 81 and 82 needs to discharge the refrigerant from the hole and store the refrigerant in the storage section 71, they are arranged a certain distance in the +Z direction from the storage section 71.

[0019] Next, the flow of refrigerant according to this embodiment will be described with reference to FIGS. 1 and 2 . First, the refrigerant is discharged from a hole formed in the refrigerant discharge pipe 81 or 82, as indicated by the solid arrows in FIG. 2 , and temporarily stored in the storage section 71. Next, the refrigerant flows down to the −Z direction side of the refrigerant tank 7 via the recess 72 and the through-hole 721, 722, or 723, as indicated by the dotted arrows in FIG. 2 . Then, the refrigerant flows down to the −Z direction side while traveling through the coil 12, bus bar 54, etc., as indicated by the solid arrows in FIGS. 1 and 2 . Thereafter, the refrigerant is temporarily stored in an oil pan located on the −Z direction side of the stator 1, and is then supplied again to the refrigerant discharge pipe 81 or 82 via a pump that applies pressure to the refrigerant and a cooler that cools the refrigerant.

[0020] The motor, which is an example of a rotating electric machine according to an embodiment, has been described above. In the motor according to the embodiment, the terminal holding member 6 and the refrigerant tank 7 are integrally formed. As a result, the motor according to the embodiment only needs to include structures, components, etc. for installing the terminal holding member 6 and the refrigerant tank 7, which are integrally formed, and does not require structures, components, etc. for installing the terminal holding member and the refrigerant tank, which are formed separately. Therefore, the motor according to the embodiment can be easily made compact, the manufacturing costs can be reduced, and it can be easily manufactured.

[0021] In the above-described embodiment, a motor is used as an example of a rotating electric machine, but the rotating electric machine according to the embodiment may be a generator that converts mechanical energy into electrical energy, instead of a motor that converts electrical energy into mechanical energy.

[0022] In the above-described embodiment, the case where the recess 72, the through-hole 721, the through-hole 722, and the through-hole 723 are formed in the bottom of the refrigerant tank 7 has been described as an example, but the present invention is not limited to this. Instead of these structures, the refrigerant tank according to the embodiment may have a conical through-hole formed in the bottom, the diameter of which in a cross section taken along a plane parallel to the XY plane decreases from the bottom surface toward the −Z direction.

[0023] The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. In other words, the present invention includes embodiments in which various modifications, substitutions, design changes, etc. have been made based on the spirit of the present invention, and does not exclude these embodiments.

[0024] 6...Terminal holding member 7...Refrigerant tank

Claims

1. A rotating electric machine comprising: a terminal holding member that holds terminals of a circuit that supplies power to a coil of the rotating electric machine; and a refrigerant tank that is formed integrally with the terminal holding member and has a storage section that temporarily stores a refrigerant that cools the rotating electric machine, and through which the refrigerant flows downward from a through hole formed in the bottom of the storage section.

Images