motor

Abstract

This invention provides a motor that suppresses corrosion that occurs at the connection point between the terminal electrodes and the aluminum rotor coil. [Solution] The motor 10 of the present disclosure is a motor comprising a stator and a wound-field type rotor, the rotor comprising a rotor core, an aluminum rotor coil wound around the rotor core, an aluminum terminal electrode provided at the end of the rotor coil, and a rotor shaft attached to the rotor core and rotating together with the rotor core, the aluminum terminal electrode being attached to the rotor shaft and configured to receive power from an electrode connected to an external power source.

Description

Technical Field

[0001] The present disclosure relates to a wound-field type motor.

Background Art

[0002] Patent Document 1 discloses a rotor of a rotating electric machine (so-called motor) having windings on a rotor. The rotor includes a cylindrical rotor core and windings wound around the rotor core. The rotor core includes a plurality of winding slots formed in the peripheral portion of the rotor core, pole teeth portions formed equidistantly in the circumferential direction in the winding slots, and a winding holding portion that is located outside the winding slots, integrated with the pole teeth portions, holds the windings in the winding slots from the outside, and is continuous between adjacent pole teeth portions. The windings are wound around the pole teeth portions two or more turns.

[0003] And the windings (hereinafter also referred to as rotor coils) are conductive wires obtained by applying an insulating coating such as enamel to a wire material of copper or aluminum.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, considering electrical connection with the outside, it is desirable to provide terminal electrodes suitable for connection at the ends of the rotor coils.

[0006] However, if the rotor coil is made of aluminum, and the terminal electrodes are made of copper or other materials, the connection between the copper terminal electrodes and the aluminum rotor coil becomes an aluminum-to-copper connection, which can easily lead to corrosion (galvanic corrosion). On the other hand, if the rotor coil is made of copper, corrosion will not occur at the connection point with the copper rotor coil if the terminal electrodes are also copper, but since copper is heavier than aluminum, the motor will be heavier, more expensive, and less recyclable. The increased weight also results in greater centrifugal force during motor rotation, and for the same strength, it is not possible to achieve a higher rotational speed compared to an aluminum rotor coil.

[0007] For example, in the case of high-power motors, the rotor is sometimes cooled with oil, but if it is affected by moisture contained in the oil, corrosion is expected to become even more severe.

[0008] This disclosure has been made in view of these circumstances, and one of its objectives is to provide a motor that suppresses corrosion occurring at the connection between the terminal electrode and the aluminum rotor coil. [Means for solving the problem]

[0009] The motor of this disclosure is a motor comprising a stator and a wound-field rotor, The rotor comprises a rotor core and An aluminum rotor coil wound around the rotor core, An aluminum terminal electrode provided at the end of the rotor coil, The rotor core is attached to the rotor shaft, which rotates together with the rotor core, The aforementioned aluminum terminal electrode is attached to the rotor shaft and is configured to receive power from an electrode connected to an external power source. [Effects of the Invention]

[0010] This disclosure provides a motor that suppresses corrosion occurring at the connection between the terminal electrodes and the aluminum rotor coil. Furthermore, aluminum is lighter than copper, allowing for weight reduction, cost reduction, and good recyclability. The reduced weight also reduces the centrifugal force during motor rotation, enabling higher rotational speeds for the same strength. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view showing the rotor of the first embodiment relating to this disclosure. [Figure 2] This is a partial cross-sectional view of a motor along the rotor shaft of the first embodiment of the present disclosure. [Figure 3] This is a cross-sectional view showing the resin mold portion of the second embodiment according to the present disclosure. [Figure 4] This is a cross-sectional view showing the resin mold portion of the third embodiment according to this disclosure. [Figure 5] This is a cross-sectional view showing the resin mold portion of the fourth embodiment according to this disclosure. [Figure 6] This is a partial cross-sectional view of a motor along the rotor shaft of the fifth embodiment of the present disclosure. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "embodiments") will be described in detail with reference to the attached drawings. Throughout the description of the embodiments, the same elements are assigned the same numbers or reference numerals.

[0013] Furthermore, the dimensional ratios in the drawings differ from the actual dimensional ratios and are merely for illustrative purposes to make the explanation easier to understand; there is no guarantee that identical parts are depicted with the same dimensions across different drawings.

[0014] Furthermore, for the sake of readability, in drawings, only some of the parts with the same attribute that exist in multiple locations may be assigned reference numerals.

[0015] <<First Embodiment>> The wound field type motor 10 according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 and 2.

[0016] FIG. 1 is a perspective view showing the rotor 30 according to the first embodiment of the present disclosure. FIG. 2 is a partial cross-sectional view of the motor 10 along the rotor shaft 31 according to the first embodiment of the present disclosure, and is a partial cross-sectional view of a portion of the motor 10 corresponding to the end side periphery of the rotor 30 on the left side of FIG. 1.

[0017] As shown in FIG. 2, the motor 10 according to the first embodiment includes a stator 20, a rotor 30 provided radially inside the stator 20, and a casing 40 that houses the stator 20 and the rotor 30. The rotor 30 may be an outer rotor provided radially outside the stator 20.

[0018] And in the internal space IS of the casing 40, a refrigerant (for example, oil such as ATF) for cooling the stator 20 and the rotor 30 is supplied, and it is a wet space. Note that the space OS outside the casing 40 is a dry space.

[0019] The stator 20 includes a stator core 21 and a stator coil 22 wound around the stator core 21.

[0020] As shown in FIG. 1, the rotor 30 includes a rotor shaft 31, a rotor core 32 provided on the rotor shaft 31, and an aluminum rotor coil 33 wound around the rotor core 32.

[0021] In the first embodiment, the rotor core 32 has an insulator 32A, and the rotor coil 33 is provided on the insulator 32A.

[0022] As shown in Figure 2, the rotor shaft 31 includes a hollow axial refrigerant passage 31A formed inside, and a radial refrigerant passage 31B located at the end of the axial refrigerant passage 31A and passing through radially to the end of the rotor coil 33 for guiding the refrigerant.

[0023] Furthermore, when the rotor 30 rotates, the centrifugal force caused by this rotation causes the refrigerant (for example, oil such as ATF) supplied to the axial refrigerant passage 31A to be discharged through the radial refrigerant passage 31B towards the end of the rotor coil 33.

[0024] Furthermore, as shown in Figure 2, the rotor 30 includes a resin molded portion 34 provided at one end (the other end in Figure 2) of either one or the other end of the rotor shaft 31, a pair of aluminum terminal electrodes 35 molded in the resin molded portion 34, and a ring member RP provided on the outer circumference of the resin molded portion 34.

[0025] Furthermore, a sealing member O1 (for example, an O-ring) is provided between the outer surface of the rotor shaft 31 and the inner surface of the resin molded portion 34, and a sealing member O2 (for example, an O-ring) is provided between the outer surface of the resin molded portion 34 and the inner surface of the ring member RP.

[0026] Furthermore, a rotational sealing member O3 (for example, a rotational oil seal) is provided between the outer surface of the ring member RP and the inner surface of the opening in the casing 40 that leads the rotor shaft 31 to the outside.

[0027] Furthermore, a bearing BG is provided in the casing 40 at a position inside the sealing member O3, which rotatably supports the ring member RP on the casing 40.

[0028] Therefore, the rotor 30 is allowed to rotate while preventing the refrigerant inside the casing 40 from leaking out of the casing 40.

[0029] As shown in Figure 2, one end 35A (right side in Figure 2) of the pair of terminal electrodes 35 is led out from the resin molded portion 34 into the wet space inside the casing 40.

[0030] Then, one end 35A is connected to the end 33A of the rotor coil 33, which is located inside the casing 40, which is a wet space, so that the terminal electrode 35 is provided on the end 33A of the rotor coil 33.

[0031] Specifically, one end 35A of one of the pair of terminal electrodes 35 is connected to one end 33A1 of the end 33A of the rotor coil 33, and the other end 35A of the other terminal electrode 35 is connected to the other end 33A2 of the end 33A of the rotor coil 33.

[0032] Regarding the connection, any connection method is acceptable as long as it ensures a secure connection that will not come loose due to vibrations during the rotation of the rotor 30. For example, a secure connection can be achieved by methods such as laser welding, thermal scribing, ultrasonic bonding, or friction stir welding.

[0033] On the other hand, the other end tip 35B of the pair of terminal electrodes 35 is provided in a ring shape (see Figure 1) along the rotational direction of the rotor 30 on the outer surface of the resin molded portion 34 located outside the casing 40, so that it can come into contact with an electrode brush (not shown) that supplies power to the rotor 30 in the dry space outside the casing 40.

[0034] As described above, the terminal electrode 35 provided at the end 33A of the aluminum rotor coil 33 is made of aluminum; in other words, in the motor 10 of the first embodiment, the rotor 30 is equipped with an aluminum terminal electrode 35 provided at the end 33A of the rotor coil 33.

[0035] Furthermore, since the end portion 33A of the rotor coil 33 is located in a wet space, the connection portion between the aluminum terminal electrode 35 provided at the end portion 33A of the rotor coil 33 and the end portion 33A of the rotor coil 33 is also located in a wet space. However, since the connection portion is made of the same type of metal, the occurrence of corrosion (galvanic corrosion) at this connection portion can be suppressed.

[0036] Furthermore, since the other end of the pair of terminal electrodes 35 (the tip 35B of the other end) is located in a dry space, even if it comes into contact with an electrode brush made of a different metal than aluminum, it is significantly less susceptible to corrosion compared to corrosion in a wet space (galvanic corrosion).

[0037] <<Second Embodiment>> Next, a wound-field type motor 10 according to a second embodiment of the present invention will be described with reference to Figure 3.

[0038] In the first embodiment, the other end 35B of a pair of aluminum terminal electrodes 35 was provided on the outer surface of the resin molded portion 34 in a ring shape (see Figure 1) along the rotational direction of the rotor 30, and was in contact with an electrode brush (not shown).

[0039] However, aluminum tends to wear down quickly when rubbed with an electrode brush (not shown), and the second embodiment describes a configuration that addresses this wear problem.

[0040] Since the motor 10 of the second embodiment has the same basic configuration as the motor 10 of the first embodiment, the following will mainly describe the differences from the first embodiment, and explanations of similarities may be omitted.

[0041] Figure 3 is a cross-sectional view showing the resin molded portion 34 of the second embodiment according to this disclosure. In Figure 3, the boundary between the wet space IS inside the casing 40 and the dry space OS outside the casing 40 is shown by a dashed line, and the location of the internal space IS and the external space OS on either side of the dashed line is indicated by a dashed arrow.

[0042] As shown in Figure 3, the rotor 30 (not shown) of the second embodiment further includes a pair of metal parts 36 made of a material different from aluminum, an electrical contact EC that electrically connects the other end 35B of the terminal electrode 35 (left end in Figure 3) and the tip 36A of one end of the metal part 36, and a resin molded part 34 that serves as a corrosion prevention part to prevent corrosion at the electrical contact EC.

[0043] The electrical contact EC connecting the other end 35B (left side in Figure 3) of the terminal electrode 35 and the tip 36A of the metal part 36 may maintain contact solely through the resin molded part 34, but to ensure a stronger connection, it may be joined using a joining method such as ultrasonic bonding or friction stir bonding.

[0044] The metal part 36 is a copper busbar that connects the electrode brush (not shown) on the outside of the mold that supplies power to the rotor 30 (not shown) to the terminal electrode 35. The other end 36B of the metal part 36 that contacts the electrode brush (not shown) is ring-shaped and aligned with the rotational direction of the rotor 30.

[0045] In particular, from the viewpoint of wear resistance due to friction with the electrode brush, it is preferable that the metal part 36 is a bronze busbar.

[0046] Furthermore, the ring-shaped tip 36B on the other end of the metal part 36 is located outside the casing 40 (not shown), which is a dry space, and has the same shape as the other end 35B of the pair of terminal electrodes 35 shown in Figure 1.

[0047] According to the motor 10 (not shown) of the second embodiment described above, the rotor 30 is equipped with a metal part 36 made of a material different from aluminum, and an electrical connection to the outside can be made at the metal part 36, so that an appropriate material can be selected for connection with the external electrodes.

[0048] Furthermore, the rotor 30 is equipped with a corrosion prevention part (in the above example, a resin molded part 34 that molds the electrical contact EC) that electrically connects the aluminum terminal electrode 35 to one side of the metal part 36 made of a material other than aluminum, thereby preventing the electrical contact EC from being exposed to a wet state.

[0049] In other words, although the electrical contact EC is located in a wet space, the corrosion prevention part (resin molded part 34) prevents the electrical contact EC from becoming wet.

[0050] Therefore, in the second embodiment, although the electrical contact EC, which is the connection point of dissimilar metals, is located in a wet space, the occurrence of corrosion (galvanic corrosion) can be significantly suppressed.

[0051] In the above description, the tip 36B on the other side of the metal part 36 is shown to be formed in a ring shape, similar to the first embodiment. However, the tip 36B on the other side of the metal part 36 may also be formed by attaching a separate copper member formed in a ring shape by welding, brazing, or the like.

[0052] In this case, since the tip 36B is made of a separate component, it is preferable to make the metal part 36 from oxygen-free copper or the like, which has low electrical resistance, and to make the separate component that forms the ring-shaped tip 63B from bronze.

[0053] Furthermore, similar to the first embodiment, since the other side of the metal part 36 (the tip 36B of the other side) is located in a dry space, even if it comes into contact with an electrode brush made of a different metal than the material of the metal part 36, it is significantly less susceptible to corrosion compared to corrosion in a wet space (galvanic corrosion).

[0054] <<Third Embodiment>> Next, a wound-field type motor 10 according to a third embodiment of the present invention will be described with reference to Figure 4.

[0055] Since the motor 10 of the third embodiment has the same basic configuration as the motor 10 of the second embodiment, the following will mainly describe the differences from the second embodiment, and explanations of similarities may be omitted.

[0056] Figure 4 is a cross-sectional view showing the resin molded portion 34 of the third embodiment according to this disclosure, and corresponds to Figure 3. In Figure 4, as in Figure 3, the boundary between the wet space IS inside the casing 40 and the dry space OS outside the casing 40 is shown by a dashed line, and the location of the internal space IS and the external space OS on either side of the dashed line is indicated by a dashed arrow.

[0057] As shown in Figure 4, the rotor 30 (not shown) of the third embodiment further includes, in addition to the resin molded portion 34, a plating 37 applied to the portion of the terminal electrode 35 corresponding to the electrical contact EC, as a corrosion prevention part.

[0058] For example, if the material is Sn (tin) or Ni (nickel), corrosion (galvanic corrosion) between it and copper and aluminum is less likely to occur, so the material of the plating 37 is preferably Sn (tin) or Ni (nickel).

[0059] In this way, for example, even if delamination occurs at the interface between the terminal electrode 35 and the resin molded part 34 due to expansion and contraction of the terminal electrode 35 caused by temperature changes during use of the motor 10, and refrigerant seeps into the electrical contact EC, corrosion (galvanic corrosion) can be suppressed because, as described above, a plating 37 that is resistant to corrosion (galvanic corrosion) is provided.

[0060] Furthermore, aluminum is prone to surface oxidation, which significantly increases its resistance. However, as described above, by providing the plating 37, it is possible to suppress the oxidative degradation of the surface of the terminal electrode 35, which is the contact surface between the metal part 36 and the terminal electrode 35.

[0061] <<Fourth Embodiment>> Next, a wound-field type motor 10 according to the fourth embodiment of the present invention will be described with reference to Figure 5.

[0062] Since the motor 10 of the fourth embodiment has the same basic configuration as the motor 10 of the second embodiment, the following will mainly describe the differences from the second embodiment, and explanations of similarities may be omitted.

[0063] Figure 5 is a cross-sectional view showing the resin molded portion 34 of the fourth embodiment according to the present disclosure, and corresponds to Figure 3. In Figure 5, as in Figure 3, the boundary between the wet space IS inside the casing 40 and the dry space OS outside the casing 40 is shown by a dashed line, and the location of the internal space IS and the external space OS on either side of the dashed line is indicated by a dashed arrow.

[0064] As shown in Figure 5, the rotor 30 (not shown) of the fourth embodiment further includes, in addition to the resin molded portion 34, a pair of oil seal portions 38 located within the resin molded portion 34 and provided on a pair of terminal electrodes 35 on the rotor coil 33 side (see Figure 2) from the electrical contact EC, as corrosion prevention parts. The oil seal portions 38 are, for example, primers.

[0065] Furthermore, because the primer has high adhesion to the aluminum and the molded resin of the resin molded portion 34, there is a possibility that delamination may occur at the interface between the terminal electrode 35 and the resin molded portion 34 as described in the third embodiment. However, at least at the oil seal portion 38, the occurrence of delamination is suppressed, thereby preventing the refrigerant from seeping into the electrical contact EC and suppressing corrosion (galvanic corrosion).

[0066] Furthermore, the oil seal portion 38 can be formed from aluminum and a resin-based material that has high adhesion to the molded resin of the resin mold portion 34, and is not limited to a primer.

[0067] Furthermore, although the oil seal portion 38 is provided on the rotor coil 33 side of the electrical contact EC (see Figure 2) as described above, an oil seal portion similar to the oil seal portion 38 may also be provided on the opposite side of the oil seal portion 38 across the electrical contact EC (left side of Figure 5).

[0068] In other words, oil seals may be provided on both sides of the electrical contact EC. In this way, if delamination or the like occurs at the interface between the metal part 36 and the resin molded part 34, outside air can enter the electrical contact EC, preventing oxidative deterioration of the surface of the terminal electrode 35, which is the contact surface between the metal part 36 and the terminal electrode 35.

[0069] Furthermore, if the outside air contains a lot of moisture, condensation may occur if the outside air enters the electrical contact EC, potentially causing corrosion (galvanic corrosion). However, as mentioned above, by providing oil seals on both sides of the electrical contact EC, it is possible to prevent outside air from entering the electrical contact EC and suppress corrosion (galvanic corrosion).

[0070] Furthermore, because the oil seal section is double-layered, it is possible to reliably prevent refrigerant from seeping out through the peeled area when a peeling occurs.

[0071] Furthermore, the plating 37 described in the third embodiment may be included as a corrosion-preventive component to further suppress corrosion (galvanic corrosion).

[0072] <<Fifth Embodiment>> Next, a wound-field type motor 10 according to a fifth embodiment of the present invention will be described with reference to Figure 6. In the previous embodiments, we have described a brushed motor 10 that supplies power to the rotor 30 by electrode brushes. In the fifth embodiment, we will describe a case where a motor 10 supplies power to the rotor 30 in a non-contact manner.

[0073] However, since the configuration of each part of the motor 10 of the fifth embodiment is similar to that of the motor 10 of the first embodiment, the same numbers will be assigned to similar components as in the first embodiment. Below, we will mainly describe the differences from the first embodiment, and omit explanations of similar components.

[0074] Figure 6 is a partial cross-sectional view of the motor 10 along the rotor shaft 31 of the fifth embodiment according to the present disclosure, and corresponds to Figure 2.

[0075] As shown in Figure 6, the motor 10 of the fifth embodiment is equipped with a power supply mechanism 50 (a so-called rotary transformer) that supplies power to the rotor 30 in a non-contact manner.

[0076] Furthermore, the rotor 30 is equipped with a rectifier diode RD, and the electrodes of the rectifier diode RD are generally made of copper for electrical connection.

[0077] As will be described later, the copper electrodes of this rectifier diode RD correspond to the metal part 36 made of a different material than aluminum.

[0078] Furthermore, the motor 10 of the fifth embodiment also includes a casing 40 that houses the stator 20 and the rotor 30. The casing 40 comprises a casing body 40A and a lid portion 40B attached to the casing body 40A to prevent refrigerant and the like from leaking to the outside. The lid portion 40B also forms a space that houses a part of the rotor 30.

[0079] Furthermore, in the fifth embodiment, since airtightness is ensured by the lid portion 40B, the sealing members O1, O2, and O3 of the first embodiment are not provided.

[0080] Therefore, the space inside the casing body 40A and the space inside the lid 40B become a wet space IS inside the casing 40 due to the refrigerant (for example, an oil such as ATF).

[0081] As shown in Figure 6, the power supply mechanism 50 includes a power transmission unit 51 provided on the lid 40B and connected to an external power source, and a power receiving unit 52 provided on the rotor 30 and rotating together with the rotor 30.

[0082] In the fifth embodiment, the power transmission unit 51 is provided with respect to the cover portion 40B, but depending on the structure of the motor 10, the power transmission unit 51 may also be provided with respect to the casing body 40A.

[0083] The power transmission unit 51 comprises a power transmission side core 51A having a recess that opens to one side (right side in Figure 6), and a power transmission side coil 51B provided in the recess of the power transmission side core 51A. The power transmission coil 51B may have a configuration in which a coil wire is wound within a recess, but it may also have, for example, a coil-shaped conductive pattern formed on a substrate.

[0084] The power receiving section 52 comprises a power receiving core 52A having a recess that opens to the other side (left side in Figure 6), and a power receiving coil 52B provided in the recess of the power receiving core 52A. The receiving coil 52B may also have a configuration in which coil wires are wound within a recess, similar to the transmitting coil 51B, but it may also have a coil-shaped conductive pattern formed on a substrate, for example.

[0085] Then, when alternating current is supplied to the power transmission unit 51 from an external power source, alternating current is generated in the power receiving unit 52, and the rectifier diode RD converts this alternating current to direct current.

[0086] Therefore, although not visible in the diagram, the rectifier diode RD is connected to the power receiving unit 52, which receives power in a non-contact manner. Specifically, the end of the receiving coil 52B is connected to the rectifier diode RD.

[0087] Furthermore, the DC voltage converted by the rectifier diode RD is supplied from the rectifier diode RD to the aluminum rotor coil 33 via the aluminum terminal electrode 35.

[0088] Furthermore, as shown in Figure 6, since the rectifier diode RD itself is located within the wet space IS inside the casing 40, the copper electrodes of the rectifier diode RD are also located within the wet space.

[0089] However, since the receiving coil 52B uses a coil wire with an insulating coating applied to the copper wire, the electrical contacts between the end of the receiving coil 52B and the rectifier diode RD are made of the same type of metal, thus suppressing corrosion (galvanic corrosion).

[0090] On the other hand, since the terminal electrode 35 is made of aluminum, as in the first embodiment, the electrical contact EC between the copper electrode (metal part 36) of the rectifier diode RD and the terminal electrode 35 electrically connects the aluminum terminal electrode 35 with a metal part made of a different material (copper).

[0091] In the fifth embodiment, the copper electrode (metal part 36) and terminal electrode 35 of the rectifier diode RD are fastened together with a bolt BLT so that they come into contact at the electrical contact EC.

[0092] Thus, the rotor 30 of the fifth embodiment also includes a metal part 36 made of a material different from aluminum, and an electrical contact EC that electrically connects the terminal electrode 35 and the metal part 36. Furthermore, the rotor 30 is equipped with a corrosion prevention part to prevent corrosion at the electrical contact EC.

[0093] Specifically, in the fifth embodiment, as described in the third embodiment, the corrosion prevention portion includes plating 37 applied to the portion of the terminal electrode 35 corresponding to the electrical contact EC. The corrosion-preventive portion may consist only of the plated 37, but it may also include a resin mold or the like.

[0094] Therefore, in the fifth embodiment as well, although the copper electrodes of the rectifier diode RD, which are metal parts 36 made of a different material than aluminum, are located in a wet space, they are equipped with a plating 37 as a corrosion-preventive part to prevent corrosion of the electrical contact EC, thus suppressing corrosion (galvanic corrosion).

[0095] On the other hand, in the fifth embodiment, the sealing members O1, O2, and O3 of the first embodiment may be provided, and the rectifier diode RD may be located in a space without refrigerant.

[0096] In this case, the electrical contact EC is also located in a space without refrigerant, but even in this case, it is equipped with plating 37 as a corrosion prevention part, so corrosion (galvanic corrosion) that may occur due to condensation can be suppressed, and oxidation deterioration of the contact surface of the aluminum terminal electrode 35 of the electrical contact EC can be prevented.

[0097] Although the above has been explained based on specific embodiments, this disclosure is not limited to the embodiments described above.

[0098] In the above embodiment, a space containing a refrigerant was shown as an example of a wet space, but any space that is prone to corrosion (galvanic corrosion) can be considered a wet space.

[0099] Thus, the scope of this disclosure also includes modifications and improvements to the embodiments, which will be apparent to those skilled in the art from the claims. [Explanation of Symbols]

[0100] 10...Motor, 20...Stator, 30...Rotor, 32...Rotor core, 33...Rotor coil, 33A...End, 34...Resin molded part, 35...Terminal electrode, 36...Metal part, 37...Plating, 38...Oil seal part, 40...Casing, EC...Electrical contact, RD...Rectifier diode

Claims

1. A motor comprising a stator and a wound-field rotor, The rotor comprises a rotor core and An aluminum rotor coil wound around the rotor core, An aluminum terminal electrode provided at the end of the rotor coil, The rotor core is attached to the rotor shaft, which rotates together with the rotor core, The aforementioned aluminum terminal electrode is attached to the rotor shaft and is configured to receive power from an electrode connected to an external power source.

2. The rotor is The electrode connected to the external power supply is made of a metal material different from aluminum, An electrical contact that electrically connects the terminal electrode and one side of the metal part, The motor according to claim 1, further comprising a corrosion prevention unit for preventing corrosion at the electrical contacts.

3. The end of the rotor coil is located in the wet space, The motor according to claim 2, wherein the other side of the metal part is located in a dry space.

4. The motor according to claim 2 or claim 3, wherein the corrosion prevention portion includes a resin molded portion for molding the electrical contacts.

5. The motor according to claim 4, wherein the corrosion prevention portion is located within the resin mold portion and includes an oil seal portion provided on the terminal electrode on the rotor coil side of the electrical contact.

6. The aforementioned metal part is a copper busbar that connects the electrode brush on the outside of the mold that supplies power to the rotor with the terminal electrode. The motor according to claim 5, wherein the tip of the metal part on the other side that contacts the electrode brush is ring-shaped along the rotational direction of the rotor.

7. The motor according to claim 2 or claim 3, wherein the corrosion-preventive portion includes plating applied to the portion of the terminal electrode corresponding to the electrical contact.

8. The aforementioned metal part is a copper electrode of a rectifier diode connected to a power receiving unit that receives power in a non-contact manner. The motor according to claim 2, wherein the corrosion-preventive portion includes plating applied to the portion of the terminal electrode corresponding to the electrical contact.

Images