JP5558211B2 - Rotor shaft for rotating electrical machine and rotor for rotating electrical machine - Google Patents

Description

  The present invention relates to a rotor shaft for a rotating electrical machine including a hollow portion having a hole at the center and a key groove, and a rotor for a rotating electrical machine.

  The rotating electrical machine includes a rotor and a stator facing the rotor. Moreover, the structure comprised by the rotor shaft which can rotate as a rotor, and the rotor core fixed to the rotor shaft is known. In such a rotor, when the rotor shaft is manufactured, the material constituting the rotor shaft is subjected to heat treatment such as carburizing quenching or induction quenching to ensure desired performance such as desired hardness and strength. Has been done.

On the other hand, in order to fix the rotor core to the rotor shaft, keys are placed on the shaft-side key grooves provided on the peripheral surface such as the outer peripheral surface of the rotor shaft and the core-side key grooves provided on the peripheral surface such as the inner peripheral surface of the rotor core. The rotor shaft and the rotor core can be integrally rotated by engaging with each other. In this case, key grooves are formed at a plurality of locations such as one or two locations on the circumferential surface of the rotor shaft.
Note that Patent Documents 1 to 3 are prior art documents related to the present invention.

JP 2009-268164 A JP 2008-272712 A JP 2007-330030 A

  When the key groove is formed on the circumferential surface of the rotor shaft as described above, when the heat treatment such as quenching is performed on the material of the rotor shaft, the shape of the rotor shaft is divided into the formed part of the key groove and the non-formed part. The heat capacity may be nonuniform in the circumferential direction, and the heat capacity may be nonuniform in the circumferential direction between the key groove formed portion and the non-formed portion. For this reason, thermal distortion tends to occur in the rotor shaft due to heat treatment, and the roundness of the rotor shaft may not be sufficiently high. In addition, when another shaft is spline-coupled to the rotor shaft, the rotor shaft is configured to have a hollow portion having a hole at the center, and one of the inner and outer peripheral surfaces of the hollow portion is splined on one peripheral surface. May be provided. In this case, a keyway is formed on the peripheral surface of the hollow portion opposite to the side where the splines are provided. When heat treatment is performed on the material constituting such a rotor shaft, the heat capacity of the hollow portion is reduced, so that thermal distortion is more likely to occur in the hollow portion, and the tip circle and root circle of the spline of the rotor shaft are more likely to occur. It becomes difficult to make the circularity sufficiently high. In this case, the accuracy of the size and shape of the spline is deteriorated, and it may be difficult to spline the rotor shaft to another shaft. Further, when the roundness of the hollow portion, the spline tip circle and the root circle of the spline is deteriorated, the vibration during rotation of the rotor shaft increases, which may increase the vibration and noise.

  In order to reduce the weight of the rotor shaft, it is also considered to promote the reduction of the radial thickness of the hollow portion. In this case, however, the heat capacity is further reduced, so that the distortion after heat treatment is larger. As a result, the roundness is more likely to deteriorate.

  In addition, the rotor shaft may be provided with a hollow portion that does not have a spline for weight reduction. In this case, the roundness of the hollow portion is deteriorated when heat treatment is performed on the material constituting the rotor shaft. there is a possibility.

  From such circumstances, in the configuration in which the rotor shaft has a hollow portion, even when heat treatment is performed on the material constituting the rotor shaft, the roundness of the circumferential surface of the hollow portion and the case where a spline is formed on this circumferential surface It is desired to easily and sufficiently increase the roundness of the tip circle and the root circle.

  On the other hand, Patent Document 1 describes a configuration in which an annular core plate is caulked and joined to each other in a laminated core of a rotor including an arc-shaped unit core for forming a rotor core having a permanent magnet mounting portion. Has been. Moreover, the unit core is provided with a plurality of rotor key grooves for positioning when the rotor core is fitted to the shaft on the surface opposite to the permanent magnet mounting portion in the radial direction.

  Further, in Patent Document 2, in a pulverizing roll including a pedestal roll having a rotating shaft and a plurality of pulverized segment members, the pedestal roll and the pulverized segment member include key grooves provided at six locations of the pedestal roll, and pulverization It describes that it connects via the common key accommodated in the keyway of a segment member.

  Further, Patent Document 3 discloses that in a ring magnet fixing structure of a rotor in which a ring magnet is fitted and fixed to the outside of a rotor shaft constituting a rotating machine, there are 4 on the outer peripheral surface of the rotor core and the inner peripheral surface of the ring magnet. It is described that a key bar is formed, and a rectangular bar-shaped key member is fitted into a hole having a rectangular cross section formed by opposing the key grooves.

  In Patent Literature 1 to Patent Literature 3 described above, in the configuration in which the rotor shaft includes a hollow portion, even when heat treatment is performed on the material constituting the rotor shaft, the roundness of the circumferential surface of the hollow portion and the circumferential surface In addition, there is no description of means that can easily and sufficiently increase the roundness of the tip circle and the root circle when splines are formed on the rotor, and matters that suggest it, and a rotor that has a hollow portion. Even the shaft is not listed.

  The present invention relates to a rotor shaft for a rotating electrical machine and a rotor for a rotating electrical machine. In the configuration in which the rotor shaft has a hollow portion, even when the material is subjected to heat treatment, the roundness of the circumferential surface of the hollow portion or the circumferential surface It is an object of the present invention to easily and sufficiently increase the roundness of a tip circle and a root circle when a spline is formed.

Rotating electric machine rotor shaft according to the present invention, a hole was perforated in the center, among the inner and outer peripheral surfaces, and a keyway on the other hand provided so as to extend in the axial direction on the side peripheral surface, the one side periphery Oite the surface, the comprises a hollow portion with respect to the keyway and a notch which is provided so as to extend in the axial direction at a position shifted in the circumferential direction, by applying a heat treatment to the material which is formed of steel or alloy The notch is different from the key groove in any one or more of a circumferential width, an axial length, and a cross-sectional shape related to a plane perpendicular to the axial direction. This is a rotor shaft for a rotating electrical machine .

According to the rotor shaft for a rotating electrical machine according to the present invention, in the configuration in which the rotor shaft has a hollow portion, the key groove and the notch are provided on one peripheral surface of the hollow portion, so that regardless of the presence of the key groove The unevenness in the circumferential direction of the heat capacity of the hollow portion can be alleviated, and the occurrence of thermal distortion in the rotor shaft can be suppressed even when heat treatment is performed on the material constituting the rotor shaft during manufacturing. For this reason, even when heat-treating the material, the roundness of the peripheral surface of the hollow portion, or the roundness of the tip circle and bottom circle when the spline is formed on this peripheral surface can be easily and sufficiently Can be high. Further, when a rotor is configured by combining a rotor core with a rotor shaft, it is possible to effectively prevent erroneous assembly in which the positional relationship of the rotor core with respect to the rotor shaft is erroneously assembled.

In the rotor shaft for a rotating electrical machine according to the present invention, preferably, the hollow portion has a spline portion provided on the other peripheral surface of the inner and outer peripheral surfaces .

  In the rotor shaft for a rotating electrical machine according to the present invention, preferably, the notch has a smaller axial length than the keyway.

Further, the rotor for a rotating electrical machine according to the present invention includes a rotor shaft for a rotating electrical machine according to the present invention and a second key groove provided on one of the inner and outer peripheral surfaces so as to extend in the axial direction. wherein the rotor core is fitted and fixed to the one side circumferential surface of the rotor shaft, and a key that engages with the second key groove and the key groove, that the key to the cut is not engaged It is the rotor for rotary electric machines characterized. A rotor for a rotating electrical machine according to the present invention is a rotor for a rotating electrical machine including a rotor shaft for a rotating electrical machine, a rotor core, and a key, and the rotor shaft has a hole at the center, both inside and outside Of the peripheral surfaces, a key groove provided to extend in the axial direction on one side peripheral surface, and provided to extend in the axial direction at a position shifted in the circumferential direction with respect to the key groove on the one side peripheral surface. The rotor core is formed by subjecting a material formed of steel or an alloy to a heat treatment, and the rotor core extends in the axial direction to one of the inner and outer peripheral surfaces. A second key groove provided on the rotor shaft, and fitted and fixed to the one circumferential surface of the rotor shaft. The key is engaged with the second key groove and the key groove. Is not engaged with the rotating electrical machine A rotor.

  According to the rotor shaft for a rotating electrical machine and the rotor for a rotating electrical machine according to the present invention, in a configuration in which the rotor shaft includes a hollow portion, even when the material is subjected to heat treatment, the roundness of the peripheral surface of the hollow portion or the circumference thereof When the spline is formed on the surface, the roundness of the tip circle and the root circle can be easily and sufficiently increased.

It is a figure which shows the structure of one example of the drive device of the hybrid vehicle incorporating the motor generator which is a rotary electric machine provided with the rotor of embodiment which concerns on this invention. FIG. 4 is a cross-sectional view taken along the line A-O-A in FIG. 3, showing an example of the rotor according to the embodiment of the present invention. It is the figure which looked at the rotor of FIG. 2 from the axial direction one side to the other side. FIG. 6 is a cross-sectional view taken along the line B-O-B in FIG. 5, showing an example rotor shaft according to the embodiment of the present invention. It is the figure which looked at the rotor shaft of FIG. 4 from the axial direction one side to the other side. It is CC sectional drawing of FIG. 7 which shows the rotor shaft of a comparative example. It is the figure which looked at the rotor shaft of FIG. 6 from the axial direction one side to the other side. It is a figure which exaggerates the deformation | transformation of each part in the state after heat-processing to the rotor shaft of FIG. It is a figure corresponding to Drawing 5 showing the rotor shaft of the 1st example of another example of an embodiment concerning the present invention. It is a figure corresponding to Drawing 5 showing the rotor shaft of the 2nd example of another example of an embodiment concerning the present invention.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. 1 to 5 show an example of an embodiment according to the present invention. The rotating electrical machine constructed by incorporating the rotor shaft for rotating electrical machine (hereinafter simply referred to as the rotor shaft) of the present embodiment is, for example, the first motor generator (MG1) 12 or the second motor constituting the driving device 10 of the hybrid vehicle. Used as a motor generator (MG2) 14. Each motor generator 12, 14 has a function as a motor or a generator.

  First, an example of a drive device for a hybrid vehicle including these motor generators 12 and 14 will be described with reference to FIG. As shown in FIG. 1, the hybrid vehicle drive device 10 includes an engine 16, a first motor generator 12, a power split unit 18, a second motor generator 14, and a reduction gear unit 20. The hybrid vehicle uses at least one of the engine 16 and the second motor generator 14 as a drive source for the vehicle.

  A power split unit 18 is connected to a drive shaft 22 of the engine 16 via a damper, and a rotary shaft of the first motor generator 12 and a reduction gear unit 20 with a two-stage speed change mechanism are connected to the power split unit 18. . Further, a rotor shaft that is a rotation shaft of the second motor generator 14 is connected to the reduction gear unit 20.

  The power split unit 18 is a planetary gear mechanism that includes a sun gear 24, a ring gear 26, a plurality of pinion gears 28, and a carrier 30. A drive shaft 22 of the engine 16 is connected to the carrier 30 via a damper, and a rotor shaft that is a rotation shaft of the first motor generator 12 is connected to the sun gear 24. Further, the output shaft 32 is connected to the ring gear 26. The rotation of the output shaft 32 is transmitted to a wheel (not shown) via a power transmission mechanism (not shown).

  The reduction gear unit 20 includes a composite planetary gear mechanism 38 including a front sun gear 34 and a rear sun gear 36, and a first braking unit 40 and a second braking unit 42. In the compound planetary gear mechanism 38, two stages of planetary gear mechanisms on the front side (right side in FIG. 1) and rear side (left side in FIG. 1) are combined by a common ring gear 44 and a long pinion gear 46. Further, the rotor shaft of the second motor generator 14 is connected to the rear sun gear 36. The operations of the first braking unit 40 and the second braking unit 42 are controlled by a control unit (not shown).

  The reduction gear unit 20 decelerates the output of the second motor generator 14 to either the low speed side or the high speed side by the operation of the first braking unit 40 or the second braking unit 42, and then extracts the output to the output shaft 32. Is possible.

  Driving of the motor generators 12 and 14 and the engine 16 is controlled by a control unit (not shown). For this reason, the driving force of at least one element of each of the motor generators 12 and 14 and the engine 16 is controlled by the control unit, taken out from the output shaft 32, and drives the wheels.

  Next, a rotating electrical machine used as the motor generators 12 and 14 constituting such a driving apparatus 10 will be described. The rotating electrical machine includes a stator and a rotor 48 (FIGS. 2 and 3) facing the stator. As shown in FIGS. 2 and 3, the rotor 48 is configured by fixing a rotor core 52 to a rotor shaft 50 that is a rotating shaft. In use, the rotor shaft 50 connects the shafts connected to the sun gears 24 and 36 (FIG. 1) by spline coupling. For this reason, as shown in FIGS. 4 and 5, the rotor shaft 50 includes a stepped cylindrical cylindrical portion 56 that is a hollow portion having a through hole 54 that is a hole portion in the center portion and penetrates in the axial direction. . Further, a female spline that is a spline portion is provided on the inner peripheral surface of a portion near one end (right end portion in FIG. 4) of the cylindrical portion 56. Although illustration of the female spline is omitted, for example, the female spline is provided in a range portion indicated by an arrow α in FIG. 4 on the inner peripheral surface of the rotor shaft 50.

  When the rotor shaft 50 is used, the end of the shaft connected to the sun gears 24 and 36 (FIG. 1) is fitted inside the portion near the one end of the rotor shaft 50, and the male spline provided on the outer peripheral surface of this shaft ( (Not shown) is spline-engaged with a female spline provided on the rotor shaft 50.

  Further, a flange 58 is provided over the entire circumference on the outer peripheral surface of the cylindrical portion 56 constituting the rotor shaft 50 near the other end (portion near the left end in FIG. 4). Further, a large-diameter cylindrical portion 60 having a diameter larger than the cylindrical portions at both ends is provided on one end side (the right end side in FIG. 4) with respect to the flange 58 of the cylindrical portion 56. Further, the rotor shaft 50 includes key grooves 62 provided to extend in the axial direction at two positions opposite to the diameter direction of the outer peripheral surface of the large-diameter cylindrical portion 60. That is, the key groove 62 for engaging the key is provided on the peripheral surface of the rotor shaft 50 opposite to the peripheral surface provided with the female spline. The cross-sectional shape related to the plane orthogonal to the axial direction of the key groove 62 is substantially rectangular. Further, the axial length L1 of the key groove 62 is matched with the axial length L1 of the large diameter cylindrical portion 60. That is, one end (the left end in FIG. 4) of the key groove 62 coincides with one side surface (the right side surface in FIG. 4) of the flange 58, and the other end (the right end in FIG. 4) of the key groove 62 is the tip of the large-diameter cylindrical portion 60. Open to the surface.

  Further, the rotor shaft 50 is provided on the outer peripheral surface of the large-diameter cylindrical portion 60 so as to extend in the axial direction at two positions on the opposite side in the diameter direction, which are 90 ° out of phase with the keyway in the circumferential direction. A pseudo keyway 64 that is a cutout is provided. The key is not engaged with the pseudo key groove 64 even during use. Further, the cross-sectional shape related to the plane orthogonal to the axial direction of the pseudo key groove 64 is a substantially rectangular shape similar to the key groove 62. One end of the pseudo key groove 64 in the axial direction (the right end in FIG. 4) is opened at the front end surface of the large-diameter cylindrical portion 60. The axial length L2 of the pseudo key groove 64 is shorter than the axial length L1 of the key groove 62. Further, the circumferential direction of the pseudo key groove 64 (the “circumferential direction” refers to the circumferential direction of the rotor shaft 50. In the present specification and claims, the meaning of “circumferential direction” is the same). And the width W1 in the circumferential direction of the key groove 62 are the same (W2 = W1). The bottoms of the key grooves 62 and the pseudo key grooves 64 are positioned on the same cylindrical surface as the outer peripheral surfaces of both ends of the cylindrical portion 56.

  Such a rotor shaft 50 constitutes the rotor 48 by combining the rotor core 52 as shown in FIGS. In this case, the rotor core 52 is constituted by, for example, a laminated body of a plurality of magnetic steel plates or a dust magnetic core. In addition, permanent magnets (not shown) are fixed at a plurality of locations in the circumferential direction of the rotor core 52. Although illustration is omitted, a pair of end plates may be provided on both sides of the rotor core 52 in the axial direction, and the rotor core 52 may be sandwiched between the pair of end plates in the axial direction.

  In addition, a pair of second key grooves 66 are provided on the inner peripheral surface of the rotor core 52 at two positions on the radially opposite side that are aligned with the key grooves 62 provided on the rotor shaft 50. The rotor core 52 is fitted and fixed to the outer peripheral surface of the large-diameter cylindrical portion 60 that is the peripheral surface provided with the key groove 62 of the rotor shaft 50. Further, the key 68 is engaged with the key groove 62 and the second key groove 66 aligned with each other. That is, the rotor 48 includes a rotor shaft 50, a rotor core 52, and a plurality of keys 68. The pseudo key groove 64 provided on the rotor shaft 50 is opposed to the cylindrical portion of the inner peripheral surface of the rotor core 52, and no key is engaged with the pseudo key groove 64.

  Further, the rotor shaft 50 is a material constituting the rotor shaft 50 at the time of manufacture, and in a state where the flange 58, the key groove 62, and the pseudo key groove 64 are formed by machining or the like on a material made of steel, an alloy, or the like, Heat treatment such as carburizing and induction hardening is performed to obtain desired performance such as hardness.

  According to such a rotor shaft 50 and the rotor 48, in the configuration in which the rotor shaft 50 includes the cylindrical portion 56 that is a hollow portion, the key groove 62 and the pseudo key groove 64 are formed on the outer peripheral surface that is one peripheral surface of the cylindrical portion 56. And are provided. For this reason, regardless of the presence of the key groove 62, the heat capacity of the cylindrical portion 56 can be alleviated in the circumferential direction, and the occurrence of thermal distortion in the rotor shaft 50 can be suppressed even when heat treatment is performed during manufacturing. Can do. Therefore, even when the material constituting the rotor shaft 50 is subjected to heat treatment, the roundness of the inner peripheral surface of the cylindrical portion 56 and the trueness of the tip circle and the root circle when the female spline is formed on the inner peripheral surface. Circularity can be easily and sufficiently high.

  Next, the effect of this embodiment will be described in detail in comparison with the case of a comparative example rotor shaft that is different from the present embodiment and deviates from the present invention. 6 to 8 show a rotor shaft 70 of a comparative example. 6 is a cross-sectional view taken along the line CC of FIG. 7 showing a rotor shaft 70 of a comparative example. FIG. 7 is a view of the rotor shaft 70 of FIG. 6 as viewed from one side in the axial direction to the other side. FIG. 8 is a diagram showing exaggerated deformation of each part after the heat treatment is performed on the rotor shaft 70 of FIG.

  In the case of the rotor shaft 70 of the comparative example shown in FIGS. 6 and 7, the pseudo key groove 64 (see FIGS. 4 and 5) has the same configuration as that of the rotor shaft 50 of the present embodiment shown in FIGS. ) Is not provided. In addition, key grooves 62 for engaging the keys are provided at two positions on the radially opposite side of the outer peripheral surface of the large-diameter cylindrical portion 60 provided on the outer peripheral surface of the rotor shaft 70. In the state in which the key groove 62 is formed in the material constituting the rotor shaft 70 of such a comparative example, the key groove 62 is formed only at two positions in the circumferential direction, so that the shape of the cylindrical portion 56 is large in the circumferential direction. It becomes uneven. For this reason, the heat capacity of the cylindrical portion 56 is also greatly uneven in the circumferential direction. When manufacturing the rotor shaft 70 of such a comparative example, if heat treatment such as quenching is performed in a state where the key groove 62 is formed in the material constituting the rotor shaft 70, as shown in an exaggerated manner in FIG. There is a possibility that the cylindrical portion 56 is thermally deformed so that the circumferential length of 62 increases toward the radially outer side of the rotor shaft 70. That is, in the cylindrical portion 56, two axes x and y that pass through the central axis O and are orthogonal to each other are defined. The y-axis passes through the two key grooves 62, and the x-axis is orthogonal to the y-axis. In this case, the cylindrical portion 56 is deformed so that the diameter is significantly reduced in the x-axis direction and the diameter is greatly increased in the y-axis direction by heat treatment, and the through hole 54 that is the inner peripheral surface of the cylindrical portion 56 is formed. The inner peripheral surface may be deformed into an ellipse. In this case, the tip deflection during rotation of the rotor shaft 70 may increase, or the shape accuracy of the female spline formed in the through hole 54 may deteriorate.

  In contrast, in the rotor shaft 50 of the present embodiment shown in FIGS. 4 and 5, the pseudo key groove 64 is provided at a position shifted from the key groove 62 of the cylindrical portion 56 in the circumferential direction. For this reason, it can relieve | moderate that the heat capacity of the cylinder part 56 becomes non-uniform | heterogenous regarding the circumferential direction. Therefore, even when heat treatment is performed on the material of the rotor shaft 50 in a state where the key groove 62 and the pseudo key groove 64 are formed on the material constituting the rotor shaft 50, the roundness of the inner peripheral surface of the cylindrical portion 56, When the female spline is formed on the peripheral surface, the roundness of the tip circle and the root circle can be easily and sufficiently increased, and a desired shape and dimensions can be easily secured. Therefore, the end of the shaft connected to the sun gears 24 and 36 (FIG. 1) is fitted to the female spline formed in the cylindrical portion 56, and the male spline provided on the outer peripheral surface of the shaft is easily engaged. Can be made. In addition, since the shape accuracy of the cylindrical portion 56 can be sufficiently increased, it is possible to suppress tip deflection during rotation of the rotor shaft 50.

  Further, in the present embodiment, the axial lengths of the key groove 62 and the pseudo key groove 64 are made different so that the axial length L2 of the pseudo key groove 64 is shorter than the axial length L1 of the key groove 62. doing. Therefore, when the rotor shaft 50 and the rotor core 52 are combined to form the rotor core 52, the operator aligns the key groove 62 and the second key groove 66 with the rotor shaft 52 on the rotor core 52. Can be easily fitted, and erroneous assembly of the rotor 48 such that the pseudo key groove 64 and the second key groove 66 are aligned and combined can be effectively prevented. That is, it is possible to effectively prevent erroneous assembly in which the positional relationship of the rotor core 52 with respect to the rotor shaft 50 is erroneously assembled. Further, since the axial length L2 of the pseudo key groove 64 is shortened, the machining operation time can be shortened. The axial length L2 of the pseudo key groove 64 is set to a length sufficient to prevent deformation of the inner peripheral surface of the cylindrical portion 56.

  Further, when the rotor 48 is configured, even if the operator mistakenly faces the pseudo key groove 64 and the second key groove and engages the rotor core 52 with the rotor shaft 50, the key 68 is moved by the pseudo key groove 64. The key can be inserted only partway through the second key groove 66, and the rest of the key 68 protrudes from the second key groove 66 in the axial direction. For this reason, the operator can easily recognize that it is necessary to reassemble again, and erroneous assembly of the rotor 48 can be effectively prevented.

  The axial length L2 of the pseudo key groove 64 may be the same as the axial length L1 of the key groove 62. However, in this case, the effect that the incorrect assembly of the rotor 48 can be effectively prevented is inferior to that of the present embodiment.

  Further, the rotor 48 of the present embodiment is not limited to the rotor constituting the rotating electrical machine used as the motor generators 12 and 14 of the drive device 10 of FIG. The rotor shaft 50 includes a hollow portion, and a key groove 62 and a pseudo key groove 64 that is a notch are formed on one of the inner and outer peripheral surfaces of the hollow portion, and a spline is formed on the other peripheral surface. That's fine.

  FIG. 9 is a view corresponding to FIG. 5 and showing a rotor shaft 50 of a first example of another example of the embodiment according to the present invention. In the rotor shaft 50 of the example shown in FIG. 9, in the same configuration as the rotor shaft 50 of the embodiment shown in FIGS. 4 and 5, the width W2 in the circumferential direction of each pseudo key groove 64 is set to each key. The circumferential width W1 of each of the pseudo key grooves 64 is made different from the circumferential width W1 of each of the pseudo key grooves 64, which is smaller than the circumferential width W1 of the groove 62 (W2 <W1).

  In the case of the configuration of FIG. 9 as well, the roundness of the inner peripheral surface of the cylindrical portion 56 can be reduced even when the material constituting the rotor shaft 50 is subjected to heat treatment, as in the configurations of FIGS. When the female spline is formed on the inner peripheral surface, the roundness of the tip circle and the root circle can be easily and sufficiently increased. 9, the circumferential width W2 of each pseudo key groove 64 is smaller than the circumferential width W1 of each key groove 62. Therefore, the circumferential width of each pseudo key groove 64 is By setting W2 to a size that does not allow the key 68 (see FIGS. 2 and 3) to enter, incorrect assembly of the rotor can be more effectively prevented. For this reason, in the configuration of FIG. 9, even when the axial length of the pseudo key groove 64 is the same as the axial length of the key groove 62, erroneous assembly can be effectively prevented. Other configurations and operations are the same as those in the embodiment shown in FIGS.

  FIG. 10 is a view corresponding to FIG. 5 and showing a rotor shaft 50 of a second example of another example of the embodiment according to the present invention. The rotor shaft 50 of the example shown in FIG. 10 has a configuration similar to that of the rotor shaft 50 of the embodiment shown in FIGS. 4 and 5 described above, and a cross-section related to a plane orthogonal to the axial direction of each pseudo key groove 64. The shape is not a rectangle but a substantially semicircular shape, which is different from a cross-sectional shape related to a plane orthogonal to the axial direction of each key groove 62.

  In the case of such a configuration of FIG. 10, it is possible to prevent the key 68 from being erroneously inserted into the pseudo key groove 64 by using a configuration having a substantially rectangular cross section as the key 68 (see FIGS. 2 and 3). Therefore, when the circumferential width of each pseudo key groove 64 is the same as the circumferential width of each key groove 62, or the axial length of each pseudo key groove 64 is equal to the axial direction of each key groove 62. Even when the length is the same, incorrect assembly of the rotor can be more effectively prevented. Other configurations and operations are the same as those in the embodiment shown in FIGS. In the configuration of FIG. 10, the cross-sectional shape related to the plane orthogonal to the axial direction of each pseudo key groove 64 is different from the cross-sectional shape related to the plane orthogonal to the axial direction of each key groove 62 other than a substantially semicircular shape. It can also be.

  As a means for effectively preventing the rotor from being misassembled, the pseudo key groove 64 has a circumferential width, an axial length, and a cross-sectional shape with respect to a plane orthogonal to the axial direction. Any one or two or more may be different. For example, the pseudo key groove 64 may be different from the key groove 62 in the circumferential width and the axial length.

  In the embodiment shown in FIGS. 1 to 5 and the embodiment shown in FIGS. 9 and 10, the key groove 62 and the pseudo key groove 64 are not limited to two. For example, only one key groove 62 and one pseudo key groove 64 may be provided, or three or more pseudo key grooves 64 may be provided.

  Further, in the embodiment of FIGS. 1 to 5 and the embodiment of FIGS. 9 and 10, the case where the spline is formed on the inner peripheral surface of the cylindrical portion 56 has been described. However, the present invention is not limited to this. For example, if the rotor shaft 50 includes a hollow portion having a hole at the center, that is, a cylindrical portion, the inner peripheral surface of the cylindrical portion is a spline. It can also be a simple cylindrical surface that does not form. Even in this case, the presence of the pseudo key groove 64 can alleviate the unevenness of the heat capacity in the circumferential direction, and the shape accuracy of the inner peripheral surface of the cylindrical portion can be ensured. For this reason, it is possible to sufficiently suppress the tip deflection during rotation of the rotor shaft 50.

  In the embodiment shown in FIGS. 1 to 5 and the embodiment shown in FIGS. 9 and 10, the rotor core 52 is fitted on the radially outer side of the rotor shaft 50 to constitute the rotor 48 (FIG. 2). However, the present invention is not limited to this. For example, a rotating electrical machine including a rotor may have a configuration in which a stator is disposed opposite to a radially inner side of a rotatable rotor, and a rotor core may be fixed to a radially inner side of a rotor shaft. In this case, the end of the shaft connected to the sun gear is fitted to the outer peripheral surface of the rotor shaft, and the female spline provided on the inner peripheral surface of the shaft is splined to the male spline provided on the outer peripheral surface of the rotor shaft. Engage. Further, a key groove and a pseudo key groove which is a notch are provided on the inner peripheral surface of the rotor shaft where no male spline is formed. Even in such a configuration, even when heat treatment is performed on the material constituting the rotor shaft, the roundness of the outer peripheral surface of the cylindrical portion that is the hollow portion of the rotor shaft and the case where a male spline is formed on this outer peripheral surface It is possible to easily and sufficiently increase the roundness of the tip circle and the root circle.

  DESCRIPTION OF SYMBOLS 10 Drive apparatus, 12 1st motor generator (MG1), 14 2nd motor generator (MG2), 16 Engine, 18 Power split part, 20 Reduction gear part, 22 Drive shaft, 24 Sun gear, 26 Ring gear, 28 Pinion gear, 30 Carrier , 32 output shaft, 34 front sun gear, 36 rear sun gear, 38 compound planetary gear mechanism, 40 first braking section, 42 second braking section, 44 ring gear, 46 long pinion gear, 48 rotor, 50 rotor shaft, 52 rotor core, 54 through Hole, 56 cylinder part, 58 flange, 60 large diameter cylindrical part, 62 key groove, 64 pseudo key groove, 66 second key groove, 68 key, 70 rotor shaft.

Claims (9)

The holes were perforated in the center, among the inner and outer peripheral surfaces, whereas the key groove provided so as to extend in the axial direction on the side peripheral surface, said one Oite the side peripheral surface, circumferential to said keyway A hollow portion having a notch provided to extend in the axial direction at a position shifted in the direction, and formed by subjecting a material formed of steel or an alloy to a heat treatment, and the notch is formed in the key groove On the other hand, a rotor shaft for a rotating electrical machine, wherein any one or more of a circumferential width, an axial length, and a cross-sectional shape with respect to a plane orthogonal to the axial direction are different. The rotor shaft for a rotating electrical machine according to claim 1,
The hollow portion, of the inner and outer peripheral surfaces, the rotational electric machine rotor shaft, characterized in that it comprises a spline portion provided on the other side periphery. In the rotor shaft for a rotating electrical machine according to claim 1 or 2,
The cut-out to said keyway, rotating electric machine rotor shaft, wherein a length in the axial direction is small. In the rotor shaft for rotating electrical machines according to any one of claims 1 to 3,
The rotor shaft for a rotating electrical machine, wherein the notch has a circumferential width smaller than the keyway. In the rotor shaft for rotating electrical machines according to any one of claims 1 to 4,
At least two of the key grooves are provided at positions shifted in the circumferential direction on the one side peripheral surface of the hollow portion,
The rotor shaft for a rotating electrical machine, wherein the notch is provided at a circumferential intermediate position between the two key grooves on one circumferential surface of the hollow portion. A rotor shaft for a rotating electrical machine according to any one of claims 1 to 5 ,
Of the inner and outer peripheral surfaces, a rotor core whereas comprises a second key groove provided so as to extend in the axial direction on the side peripheral surface, which is fitted and fixed to the one side circumferential surface of the rotor shaft,
And a key for engaging the said key groove and said second key groove,
A rotor for a rotating electrical machine, wherein a key is not engaged with the notch. A rotor for a rotating electrical machine comprising a rotor shaft for a rotating electrical machine, a rotor core, and a key,
The rotor shaft is
A key groove having a hole in the center and provided on one of the inner and outer peripheral surfaces so as to extend in the axial direction, and a shift in the circumferential direction relative to the key groove on the one peripheral surface A hollow portion having a notch provided so as to extend in the axial direction at a certain position, and formed by subjecting a material formed of steel or an alloy to heat treatment,
The rotor core includes a second key groove provided so as to extend in the axial direction on one side peripheral surface of the inner and outer peripheral surfaces, and is fitted and fixed to the one side peripheral surface of the rotor shaft,
The key is engaged with the second keyway and the keyway;
A rotor for a rotating electrical machine, wherein a key is not engaged with the notch. The rotor for a rotating electrical machine according to claim 7,
The said hollow part has a spline part provided in the other side peripheral surface among internal and external peripheral surfaces, The rotor for rotary electric machines characterized by the above-mentioned. The rotor for a rotating electrical machine according to claim 7 or 8,
At least two of the key grooves are provided at positions shifted in the circumferential direction on the one side peripheral surface of the hollow portion,
The rotor for a rotating electrical machine, wherein the notch is provided at a circumferential intermediate position between the two key grooves on one circumferential surface of the hollow portion.

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