Rotary electric machine, railway vehicle using the same, and mobility device

Abstract

To be able to securely support and fix a magnetic wedge even in the event of temperature changes due to starting, stopping, or changes in load, etc., to achieve long-term reliability and of course to prevent vibrations due to electromagnetic vibration forces by making the magnetic wedge more robust.SOLUTION: A rotary electric machine consists of a stator and a rotor. The stator is configured with stator coils and a stator iron core. The stator iron core has stator slots that store the stator coils. Slot opening parts are formed on the gap side of the stator slots. Magnetic wedges 10 are arranged in the slot opening parts to hold the stator coils. The magnetic wedges are inserted into grooves 9a on the side of the slot opening parts in the stator iron core. Clearances 15 are provided between the magnetic wedges and the stator iron core on the anti-gap side facing the circumferential edge parts of the magnetic wedges. The clearances are filled with varnish 16.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a rotating electric motor and a railway vehicle and mobility device using the same, and in particular to a rotating electric motor suitable for one having a magnetic wedge installed at the slot opening after the stator coil is inserted to prevent the stator coil from detaching from the stator slot, and a railway vehicle and mobility device using the same. [Background technology]

[0002] In recent years, there has been a demand for high efficiency rotating electrical machines to save energy and reduce carbon dioxide emissions as electrification advances. In particular, it is important to improve the efficiency of induction motors, which are already widely used in industry and for mobility, including railways.

[0003] Induction motors have conductor bars in the rotor, but it is known that a loss called high-frequency secondary copper loss occurs in these conductor bars due to permeance changes in the slots, which reduces efficiency. The use of magnetic wedges has been proposed as an item for reducing this high-frequency secondary copper loss.

[0004] A wedge is a component placed at the slot opening after the stator coil of an induction motor is inserted to prevent the stator coil from coming off the stator slot. Generally, a non-magnetic material is used as the material for the wedge, but a magnetic wedge is a wedge that has been made magnetic.

[0005] Since efficiency can be easily increased by simply replacing conventional non-magnetic wedges with magnetic wedges, in recent years magnetic wedges have come to be regarded as an important item for increasing the efficiency of not only induction motors but also a wide range of rotating electrical machines.

[0006] However, since the magnetic wedge itself is magnetic and is subjected to electromagnetic excitation force, there is a risk of noise increase due to vibration of the magnetic wedge and failure of the rotating electric machine due to the magnetic wedge being broken. Therefore, the technology for fixing the magnetic wedge is important for obtaining a highly efficient rotating electric machine.

[0007] An example of a prior art document related to the above-mentioned fixing technology of the magnetic wedge is "Magnetic Wedge of Rotating Electric Machine" in Patent Document 1.

[0008] Paragraph 1 of this patent document

[0009] Patent Document 1 states that "A magnetic wedge 5 is inserted into the opening 2a of the slot 2 to support and fix the winding 4. The magnetic wedge 5 is fixed in a groove provided in the side wall of the core teeth 1a, 1b, and holds the magnetic wedge 5 itself and supports and fixes the winding 4." In Patent Document 1, grooves are provided in the side wall of the core teeth 1a, 1b of the slot 2 of the stator core 1, and the magnetic wedge 5 is inserted into the groove to be fixed. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 5-22885 Summary of the Invention [Problem to be solved by the invention]

[0010] Typically, rotating electric machines have a thickness in the axial direction, which results in three-dimensional dimensional variation. Due to this three-dimensional dimensional variation, the magnetic wedge fixing technology described in Patent Document 1 mentioned above has problems with areas where contact cannot be made between the magnetic wedge and the groove of the stator, and these areas where contact cannot be made become weak, making the magnetic wedge susceptible to vibration due to electromagnetic excitation forces.

[0011] Furthermore, it is known that actual rotating electric machines repeatedly undergo temperature changes, such as high and low temperatures, due to starting and stopping or changes in load, and the magnetic wedge fixing technology described in the above-mentioned Patent Document 1 does not take into account the effects of the magnetic wedge becoming tightly fixed or, conversely, loosening, due to the above-mentioned temperature changes, and is therefore insufficient in terms of long-term reliability.

[0012] The present invention has been developed in consideration of the above-mentioned points, and its object is to provide a rotating electric machine that can not only securely hold the magnetic wedge to prevent vibrations caused by electromagnetic excitation forces, but also reliably support and fix the magnetic wedge even when subjected to temperature changes due to starting, stopping, or changes in load, etc., thereby achieving long-term reliability, and a railway vehicle and mobility device using the same. [Means for solving the problem]

[0013] In order to achieve the above-mentioned object, the rotating electric machine of the present invention comprises a stator and a rotor arranged radially from the stator with a predetermined gap therebetween, the stator being composed of a stator coil and a stator core, the stator core having stator slots for accommodating the stator coil, a slot opening being formed on the gap side of the stator slot, and a magnetic wedge for holding the stator coil being disposed in the slot opening, the magnetic wedge being inserted into a groove on the side of the slot opening of the stator core, and a clearance being provided in the groove between the magnetic wedge and the stator core on the anti-gap side facing the circumferential end of the magnetic wedge, and the clearance being filled with varnish.

[0014] In addition, in order to achieve the above-mentioned objective, the railway vehicle of the present invention is a railway vehicle comprising a rotating electric machine, wheels that are rotated and driven by the rotating electric machine via axles, and a bogie that supports the rotating electric machine via a support member, and is characterized in that the rotating electric machine is a rotating electric machine of the above-mentioned configuration.

[0015] In addition, in order to achieve the above-mentioned object, the mobility device of the present invention is a mobility device comprising a rotating electric motor, a wheel that is rotated and driven by the rotating electric motor via an axle, and a mobility that supports the rotating electric motor via a support member, wherein the rotating electric motor is a rotating electric motor of the above-mentioned configuration. Effect of the Invention

[0016] According to the present invention, the magnetic wedge can be held firmly to prevent vibration caused by electromagnetic excitation force, and the magnetic wedge can be reliably supported and fixed even against temperature changes caused by starting, stopping, or load changes, etc., thereby achieving long-term reliability. [Brief description of the drawings]

[0017] [Figure 1] 1 is a half sectional view showing an overall configuration of a rotating electric machine according to a first embodiment of the present invention; [Diagram 2] FIG. 2 is a cross-sectional view taken along the line AA′ in FIG. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of a stator slot portion in FIG. 2. [Figure 4] 4 is a diagram showing a state in which the stator coil has contracted from the state shown in FIG. 3, forming a gap (space) between the stator coil and the magnetic wedge. [Diagram 5] FIG. 2 shows a rotary electric machine according to a second embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. [Figure 6] FIG. 11 shows a rotary electric machine according to a third embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. [Figure 7] FIG. 11 shows a rotary electric machine according to a fourth embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. [Figure 8] FIG. 11 is a diagram showing an example in which a buffer member used in a rotating electric machine according to a fourth embodiment of the present invention is made of a plurality of laminated insulating papers, and corresponds to FIG. 3 in the first embodiment. [Figure 9] FIG. 11 is a diagram showing an example in which a buffer member used in a rotating electric machine according to a fourth embodiment of the present invention is made of folded insulating paper, and corresponds to FIG. 3 in the first embodiment. [Figure 10] FIG. 11 shows a rotary electric machine according to a fifth embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. [Figure 11] FIG. 11 shows a rotating electric machine according to a sixth embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. [Figure 12] FIG. 11 is a schematic configuration diagram showing a seventh embodiment of the present invention, which is a railway vehicle employing any one of the rotating electric machines of the first to sixth embodiments. [Figure 13]FIG. 13 is a schematic configuration diagram showing a mobility device according to an eighth embodiment of the present invention, which employs any one of the rotating electric machines according to the first to sixth embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, a rotating electric machine according to the present invention and a railway vehicle and a mobility device using the same will be described based on the illustrated embodiments. In each embodiment described below, the same reference numerals will be used for the same components. EXAMPLES

[0019] FIG. 1 shows a half cross-sectional view of the overall configuration of a rotating electric machine 100 according to a first embodiment of the present invention, and FIG. 2 shows a cross-sectional view taken along line AA' in FIG.

[0020] 1, in a rotating electric machine 100 of this embodiment, a rotor 2 and a stator 3 are arranged in a frame 1 so as to face the rotor 2 in the radial direction with a predetermined gap 14 between them. Bearings 4a and 4b that support the rotor 2 for rotation are installed in the frame 1.

[0021] The rotor 2 is fastened to the shaft 5 and has conductor bars 12 arranged in slots of the rotor core 7, the conductor bars 12 protruding in the axial direction from both axial ends and end rings 8 connected to both axial ends.

[0022] On the other hand, the stator 3 is fixed to the frame 1, and is provided with a stator coil 13 arranged in a stator slot 11 of the stator core 9, and this stator coil 13 has stator coil ends 13a protruding in the axial direction from both axial ends.

[0023] As shown in Figures 1 and 2, the main components that make up the rotor 2 and stator 3 are roughly composed of a rotor core 7, a stator core 9, conductor bars 12, a stator coil 13, a gap 14, and a magnetic wedge 10 made of an iron-based magnetic material that prevents the stator coil 13 from popping out.

[0024] An axial duct 18 for flowing the coolant in the axial direction may be provided on the inner diameter side of the rotor core 7, and a frame 1 fixed to the stator 3 is arranged on the outer diameter side of the stator 3, with the fixing parts of the stator 3 and the frame 1 fixed at a predetermined interval in the circumferential direction, and a ventilation duct 19 for flowing the coolant in the axial direction may be provided between the fixing parts. Reference numeral 6 denotes stator teeth.

[0025] Next, the magnetic wedge 10 in the rotating electric machine 100 of this embodiment will be specifically described with reference to Fig. 3. Fig. 3 is an enlarged cross-sectional view of the stator slot 11 portion in Fig. 2. As shown in FIG. 3, the stator core 9 has stator slots 11 that house the stator coils 13, and a slot opening 11a is formed on the gap 14 side of the stator slots 11 (upper side in FIG. 3), and a magnetic wedge 10 that holds the stator coils 13 is arranged in the slot opening 11a.

[0026] In this embodiment, the magnetic wedge 10 is inserted into the groove 9a on the side of the slot opening 11a of the stator core 9, and in this groove 9a, a clearance 15 having a radial width of 0.1 to 2 mm is provided between the magnetic wedge 10 and the stator core 9 on the anti-gap side (lower side in Figure 3) facing the circumferential end (left / right direction in Figure 3) of the magnetic wedge 10, and this clearance 15 is filled with varnish 16.

[0027] The above-mentioned varnish 16 only needs to be filled into at least the clearance 15, but since the clearance 15 is connected to the stator slot 11 into which the stator coil 13 is inserted, the varnish 16 is filled not only into the clearance 15 but also into the stator slot 11 into which the stator coil 13 is inserted.

[0028] By providing the above-mentioned clearance 15, the magnetic wedge 10 and the varnish 16 are adhered not only to the opposing surfaces of the magnetic wedge 10 and the stator coil 13 but also to the opposing surfaces of the magnetic wedge 10 and the groove portion 9a.

[0029] Generally, the linear expansion coefficients of the stator core 9 and the stator coil 13 are different, so there is a risk that the varnish 16 on the opposing surface between the magnetic wedge 10 and the stator coil 13 will peel off due to thermal expansion and contraction of the stator core 9 and the stator coil 13 (expansion and contraction of parts due to heating and cooling) (a state in which a gap (space) 17 in Figure 4 is formed).

[0030] On the other hand, since the only surrounding material for the magnetic wedge 10 in the groove portion 9a is the stator core 9, there is almost no change in the width of the clearance 15 due to thermal contraction of the material, and the varnish 16 on the opposing surface between the magnetic wedge 10 and the groove portion 9a does not peel off even if there is a temperature change in the rotating motor 100, allowing the magnetic wedge 10 to be fixed and supported to the stator 3.

[0031] In this embodiment, the cross-sectional shape of the varnish 16 filled in both the clearance 15 and the stator slot 11 is approximately Γ-shaped (part G in Figures 3 and 4), or if there is a gap (space) between the magnetic wedge 10 and the stator coil 13, it is approximately Π-shaped (part P in Figure 5).

[0032] Next, a description will be given of the assembly of the stator 3 in the structure of this embodiment described above, and the holding state of the magnetic wedges 10 during operation.

[0033] In the assembly process of the stator 3, first, the stator coils 13 are inserted into the stator slots 11 of the stator core 9, and then the magnetic wedges 10 are inserted from the axial direction. Then, the stator 3 is heated, and varnish 16 is injected into the stator slots 11 in a high-temperature state and cured at high temperature.

[0034] At this time, since the stator 3 is in a high temperature state, each component that constitutes the stator 3 undergoes thermal expansion. In particular, when comparing the linear expansion coefficients of the stator core 9 (mainly iron) and the stator coil 13 (mainly copper), the stator coil 13 has a larger linear expansion coefficient. Therefore, due to the thermal expansion of the stator coil 13, the magnetic wedge 10 is subjected to surface pressure in the direction of the gap 14.

[0035] That is, since the magnetic wedge 10 and the stator coil 13 are in close contact with each other, the varnish 16 is hardly filled between the magnetic wedge 10 and the stator coil 13 .

[0036] However, in the groove 9a into which the magnetic wedge 10 is inserted, a clearance 15 is provided between the magnetic wedge 10 and the stator core 9 on the anti-gap side (lower side in FIG. 3) facing the circumferential end (left and right direction in FIG. 3) of the magnetic wedge 10, so the injected varnish 16 fills and hardens not only on the circumferential side surface of the stator coil 13, but also in the clearance 15 in the groove 9a. At this time, the cross-sectional shape of the varnish 16 filled in both the clearance 15 and the stator slot 11 is approximately Γ-shaped.

[0037] When the stator 3 is cooled after the hardening conditions of the varnish 16 are satisfied, the stator core 9 and stator coil 13, which have been thermally expanded, contract. At this time, the stator coil 13, which has expanded, tries to contract in the radial direction. Since there is no or almost no varnish 16 between the magnetic wedge 10 and the stator coil 13, which were in close contact when the varnish 16 was injected, the magnetic wedge 10 and the stator coil 13 easily peel off. On the other hand, the radial depth of the clearance 15 of the groove portion 9a is short (narrow) compared to the radial depth of the stator slot 11, so it is less susceptible to the effects of thermal contraction.

[0038] Therefore, the varnish 16 filled in the clearance 15 adheres to the magnetic wedge 10 without peeling off, and the magnetic wedge 10 is fixed and supported by the stator core 9.

[0039] Since the varnish 16 is injected in liquid form and then hardened (solidified), it has a thickness in the axial direction of the rotating motor 100, and even if there is variation in three-dimensional dimensions, the varnish 16 can be reliably filled into the clearance 15 between the magnetic wedge 10 and the groove 9a of the stator core 9, so that the magnetic wedge 10 is reliably fixed and supported in the clearance 15 and will not vibrate even when subjected to electromagnetic excitation force.

[0040] In this manner, in the configuration of this embodiment, the magnetic wedge 10 can be fixed and supported in the stator slot 11 by the solid varnish 16 filled in the clearance 15, regardless of temperature conditions, and therefore the magnetic wedge 10 is securely fixed and supported, and will not vibrate even when subjected to electromagnetic excitation force.

[0041] This reduces the occurrence of an increase in noise caused by vibration of the magnetic wedge 10 and a malfunction of the rotating electric machine 100 caused by cracking of the magnetic wedge 10. In addition, since the magnetic wedge 10 can be reliably fixed and supported without problems even when the surrounding material is thermally contracted due to temperature changes, a rotating electric machine 100 including a stator 3 with high long-term reliability can be provided.

[0042] Furthermore, since it becomes possible to provide a rotating electric machine 100 using magnetic wedges 10 with long-term reliability, it is possible to reduce high-frequency loss due to high-frequency magnetic flux generated on the surface of gap 14 between stator 3 and rotor 2 of rotating electric machine 100, thereby making rotating electric machine 100 highly efficient. In particular, when rotating electric machine 100 is an induction motor, it is possible to reduce high-frequency secondary copper loss, thereby making it possible to achieve high efficiency of the induction motor at low cost.

[0043] In this embodiment, the difference in linear expansion coefficient between the stator core 9 and the magnetic wedge 10 is made smaller than the difference in linear expansion coefficient between the stator core 9 and the stator coil 13. That is, the stator core 9 is made mainly of iron, and the stator coil 13 is made mainly of copper, and the material of the magnetic wedge 10 is an iron-based magnetic member.

[0044] In this way, by making the difference in linear expansion coefficient between the stator core 9 and the magnetic wedge 10 smaller than the difference in linear expansion coefficient between the stator core 9 and the stator coil 13, the change in width of the clearance 15 of the groove portion 9a due to thermal contraction of the stator core 9 and the magnetic wedge 10 becomes relatively small.

[0045] As a result, the varnish 16 on the opposing surface of the magnetic wedge 10 and the groove portion 9a can adhere and hold the magnetic wedge 10 to the stator 3 without being subjected to thermal stress even when the temperature of the rotating motor 100 changes, thereby increasing the holding force of the magnetic wedge 10 by the varnish 16 and improving the long-term reliability of the rotating motor 100.

[0046] In addition, in this embodiment, the magnetic wedge 10 has a shape that is convex toward the gap 14 side (upper side in Figure 3), or the cross-sectional shape of the magnetic wedge 10 is a trapezoidal shape that is convex toward the gap 14 side (upper side in Figure 3).

[0047] As the magnetic wedge 10 is convex toward the gap 14, the magnetic wedge 10 protrudes radially (upper side in FIG. 3 ) toward the gap 14 beyond the groove 9a. As the tip of the magnetic wedge 10 approaches the gap 14, the pulsation of magnetic flux caused by high frequency generated on the gap 14 surface between the stator 3 and the rotor 2 is effectively mitigated.

[0048] This makes it possible to reduce high-frequency losses, for example, high-frequency secondary copper loss occurring in the conductor bars 12 of the rotor 2, and improve the efficiency of the rotating electric machine 100. Therefore, the power consumption required to operate the rotating electric machine 100 can be reduced, which contributes to reducing CO2 emissions.

[0049] In addition, since the cross-sectional shape of the magnetic wedge 10 is a trapezoid convex toward the gap 14 side, not only is the pulsation of magnetic flux caused by high frequency generated on the gap 14 surface between the stator 3 and the rotor 2 effectively mitigated, but also, since the cross section of the groove portion 9a on the gap 14 side and the cross section of the magnetic wedge 10 do not have any acute angles, including right angles, when the magnetic wedge 10 is subjected to pressure from the stator coil 13 at high temperatures, local concentration of stress generated in the stator teeth 6 and the magnetic wedge 10 is mitigated.

[0050] This not only reduces high-frequency secondary copper loss, but also alleviates local concentration of stress on the stator teeth 6 and the magnetic wedges 10, thereby preventing plastic deformation and cracking of the tips of the stator teeth 6 and the magnetic wedges 10, thereby improving the long-term reliability of the rotating electric motor 100.

[0051] According to the configuration of this embodiment, the magnetic wedge 10 is held firmly to prevent vibration due to electromagnetic excitation force, and the magnetic wedge 10 can be reliably supported and fixed even against temperature changes due to starting, stopping, or load changes, etc., thereby obtaining long-term reliability. EXAMPLES

[0052] Second Embodiment Fig. 5 shows a rotating electric machine 100 according to a second embodiment of the present invention. Fig. 5 is a diagram corresponding to Fig. 3 of the first embodiment.

[0053] As shown in FIG. 5, in this embodiment, a second clearance 15a is provided between the magnetic wedge 10 and the stator coil 13, and the second clearance 15a is filled with varnish 16.

[0054] By configuring this embodiment in this manner, it is possible to obtain the same effects as in the first embodiment, and also the change in pressure caused by the thermal expansion and contraction of the stator coil 13 can be mitigated by the viscoelasticity of the varnish 16 filled in the second clearance 15a, thereby mitigating the impact load applied to the magnetic wedge 10. This makes the magnetic wedge 10 less likely to crack, improving the long-term reliability of the rotating electric machine 100.

[0055] The injected varnish 16 fills and hardens not only the circumferential side surfaces of the stator coil 13 but also the clearances 15 and second clearances 15a in the grooves 9a. That is, the cross-sectional shape of the varnish 16 filled in the clearances 15, second clearances 15a and stator slots 11 becomes approximately Π-shaped.

[0056] This increases the contact area between the magnetic wedge 10 and the varnish 16, thereby increasing the holding force of the magnetic wedge 10 by the varnish 16 and improving the long-term reliability of the rotating electric machine 100. EXAMPLES

[0057] Third Embodiment Fig. 6 shows a third embodiment of the rotating electric machine 100 according to the present invention. Fig. 6 is a diagram corresponding to Fig. 3 of the first embodiment.

[0058] As shown in FIG. 6, in this embodiment, a second clearance 15a is provided between the magnetic wedge 10 and the stator coil 13, and a buffer member 20 is disposed in this second clearance 15a.

[0059] By configuring this embodiment in this manner, it is possible to obtain the same effects as in the first embodiment, and also the change in pressure caused by the thermal expansion and contraction of the stator coil 13 can be mitigated by the viscoelasticity of the buffer material 20 filled in the second clearance 15a, thereby mitigating the impact load applied to the magnetic wedge 10. This makes the magnetic wedge 10 less likely to crack, improving the long-term reliability of the rotating electric machine 100.

[0060] Furthermore, when the buffer member 20 is made of a material that absorbs the varnish 16, such as insulating paper, the varnish is filled and hardened not only on the circumferential side surface of the stator coil 13 but also in the clearance 15 in the groove 9a and the buffer member 20. That is, the cross-sectional shape of the varnish 16 filled in the clearance 15, the buffer member 20, and the stator slot 11 becomes approximately Π-shaped.

[0061] This increases the contact area between the magnetic wedge 10 and the varnish 16 (including the buffer member 20), thereby increasing the holding force of the magnetic wedge 10 by the varnish 16 and improving the long-term reliability of the rotating electric machine 100. EXAMPLES

[0062] Fourth embodiment of the rotating electric machine 100 of the present invention is shown in Fig. 7. Fig. 7 is a diagram corresponding to Fig. 3 of the first embodiment.

[0063] As shown in FIG. 7, in this embodiment, a second clearance 15a is provided between the magnetic wedge 10 and the stator coil 13, and a buffer member 20a is disposed in the clearance 15 of the groove portion 9a and the second clearance 15a.

[0064] By configuring this embodiment in this manner, it is of course possible to obtain the same effects as in embodiment 1, and since a buffer member 20a made of a solid material is disposed in groove portion 9a, the magnetic wedge 10 is fixed and held to the stator core 9 by the static friction force between the magnetic wedge 10 and buffer member 20a.

[0065] When the buffer member 20a is made of a material that absorbs the varnish 16, such as insulating paper, the magnetic wedge 10 is fixed and held to the stator core 9 not only by the static friction force between the magnetic wedge 10 and the buffer member 20a but also by the adhesive force of the varnish 16, thereby increasing the holding force of the magnetic wedge 10 and improving the long-term reliability of the rotating electric motor 100.

[0066] Furthermore, by disposing the buffer member 20a in the second clearance 15a, the change in pressure caused by the thermal expansion and contraction of the stator coil 13 can be mitigated by the viscoelasticity of the buffer member 20a filled in the second clearance 15a, and the impact load applied to the magnetic wedge 10 is mitigated. This makes the magnetic wedge 10 less likely to crack, improving the long-term reliability of the rotating electric machine 100.

[0067] Furthermore, if the buffer material 20a is made of a material that absorbs the varnish 16, such as insulating paper, the varnish is filled and hardened not only on the circumferential side surface of the stator coil 13, but also in the buffer material 20a in the clearance 15 in the groove 9a and the buffer material 20a in the second clearance 15a. That is, the cross-sectional shape of the varnish 16 filled in the buffer material 20a and the stator slot 11 becomes approximately Π-shaped.

[0068] This increases the contact area between the magnetic wedge 10 and the varnish 16 absorbed in the buffer member 20a, thereby increasing the holding force of the varnish 16 on the magnetic wedge 10 and improving the long-term reliability of the rotating electric machine 100.

[0069] In this embodiment, the cushioning member 20a is made of multiple laminated sheets of insulating paper 20a1 as shown in FIG. 8, or is made of folded insulating paper 20a2 as shown in FIG. 9.

[0070] By forming the buffer member 20a from a plurality of laminated insulating papers 20a1, the workability of inserting the magnetic wedge 10 into the groove 9a is improved.

[0071] In other words, in the conventional structure, after inserting the stator coil 13 into the stator slot 11, when the magnetic wedge 10 is inserted from the axial direction, there is a pressure from the stator coil 13, and the magnetic wedge 10 is inserted while being subjected to kinetic friction force with the groove portion 9a and the stator coil 13. However, since the friction coefficient of the surfaces of each component is large, a large force acts on the magnetic wedge 10 when it is inserted, which could lead to damage to the magnetic wedge 10 or destruction of the insulating coating of the stator coil 13.

[0072] In contrast, in the buffer member 20a composed of multiple stacked sheets of insulating paper 20a1 as shown in FIG. 8, when the magnetic wedge 10 is inserted from the axial direction, slippage occurs between the multiple stacked sheets of insulating paper 20a1, making it easier to insert the stator coil 13 from the axial direction, eliminating the possibility of damage to the magnetic wedge 10 or destruction of the insulating coating of the stator coil 13 during assembly, and improving the long-term reliability of the rotating electric machine 100.

[0073] In addition, the cushioning member 20a made of folded insulating paper 20a2 as shown in Figure 9 makes it easy to secure the clearance 15 for filling with varnish 16 due to the springiness of the folded insulating paper 20a2, making it easier to assemble the rotating electric machine 100.

[0074] Incidentally, since the varnish 16 is also absorbed by the folded insulating paper 20a2, even if the folded insulating paper 20a2 is placed in the clearance 15 of the groove portion 9a, the clearance 15 is filled with the varnish 16 necessary for adhering the magnetic wedge 10, so even in the structure shown in Figure 9, the magnetic wedge 10 can be fixed and held to the stator core 9 by the adhesive force of the varnish 16 filled in the clearance 15 of the groove portion 9a. EXAMPLES

[0075] Fig. 10 shows a fifth embodiment of the rotating electric machine 100 according to the present invention. Fig. 10 is a diagram corresponding to Fig. 3 of the first embodiment.

[0076] As shown in Figure 10, in this embodiment, the groove portion 9a is formed in a stepped shape, and the end of the magnetic wedge 10 is inserted into the deepest point (deepest part) 9a1 in the circumferential direction (left and right direction in Figure 10) of this stepped groove portion 9a, and the stator core 9 and the magnetic wedge 10 are in contact with each other at the deepest part 9a1 in the circumferential direction of the stepped groove portion 9a.

[0077] By configuring this embodiment in this manner, it is of course possible to obtain the same effects as in embodiment 1, and since the magnetic wedge 10 is in contact with the stator core 9 at the deepest part 9a1 of the stepped groove portion 9a, the magnetic wedge 10 is fixed and supported not only by the adhesive strength of the varnish 16 but also by metal-to-metal contact with the stator core 9.

[0078] Therefore, even if the adhesive strength of the varnish 16 weakens, the magnetic wedge 10 is held by the stator core 9, and therefore the magnetic wedge 10 can be prevented from vibrating immediately and becoming damaged.

[0079] Furthermore, even if the magnetic wedge 10 heats up and expands due to an increase in the amount of harmonic magnetic flux, the thermal expansion of the magnetic wedge 10 can be suppressed by the metal-touch portion with the stator core 9, eliminating the risk of crushing the varnish 16 in the clearance 15 in the groove portion 9a.

[0080] As a result, the magnetic wedge 10 is held to the stator core 9 by the stable adhesive force of the varnish 16, thereby improving the long-term reliability of the rotating electric machine 100. EXAMPLES

[0081] Sixth embodiment of the rotating electric machine 100 according to the present invention is shown in Fig. 11. Fig. 11 is a diagram corresponding to Fig. 3 of the first embodiment.

[0082] As shown in Figure 11, in this embodiment, groove portion 9a is formed in a tapered shape, and the end of magnetic wedge 10 is inserted into the deepest point (deepest part) 9a1 in the circumferential direction (left and right direction in Figure 11) of groove portion 9a, and the stator core 9 and magnetic wedge 10 are in contact with each other at the deepest part 9a1 in the circumferential direction of the tapered groove portion 9a.

[0083] By configuring this embodiment in this manner, it is of course possible to obtain the same effects as in embodiment 1, and since the magnetic wedge 10 is in contact with the stator core 9 at the deepest part 9a1 of the tapered groove portion 9a, the magnetic wedge 10 is fixed and supported not only by the adhesive strength of the varnish 16 but also by metal-to-metal contact with the stator core 9.

[0084] Therefore, even if the adhesive strength of the varnish 16 weakens, the magnetic wedge 10 is held by the stator core 9, and therefore the magnetic wedge 10 can be prevented from vibrating immediately and becoming damaged.

[0085] Furthermore, even if the magnetic wedge 10 heats up and expands due to an increase in the amount of harmonic magnetic flux, the thermal expansion of the magnetic wedge 10 can be suppressed by the metal-touch portion with the stator core 9, eliminating the risk of crushing the varnish 16 in the clearance 15 in the groove portion 9a.

[0086] As a result, the magnetic wedge 10 is held to the stator core 9 by the stable adhesive force of the varnish 16, thereby improving the long-term reliability of the rotating electric machine 100.

[0087] Furthermore, by forming groove 9a in a tapered shape, the tapered portion also serves as a guide for positioning when magnetic wedge 10 is inserted from the axial direction, improving manufacturability. EXAMPLES

[0088] FIG. 12 shows a schematic configuration of a railway vehicle 200 employing any one of the rotating electric machines 100 according to the first to sixth embodiments described above, as a seventh embodiment of the present invention.

[0089] As shown in FIG. 12, the railway vehicle 200 is roughly composed of a rotating electric machine 100, wheels 102a that are rotated and driven by the rotating electric machine 100 via axles 101a, and a bogie 104 that supports the rotating electric machine 100 via support members 103a, where the rotating electric machine 100 is any one of the rotating electric machines 100 described in the above-mentioned Examples 1 to 6.

[0090] That is, the rotating electric machine 100 of the railway vehicle 200 is fixedly supported on a bogie 104 by a support member 103a, the rotor 2 of the rotating electric machine 100 is directly connected to an axle 101a, and the rotating electric machine 100 is configured to drive wheels 102a via the axle 101a.

[0091] Generally, the rotating electric machine 100 that drives the railway vehicle 200 is mounted on a bogie 104, and is therefore subjected to vibrations caused not only by the rotating electric machine 100 but also by external factors, such as vibrations caused by distortions or unevenness of the rails, or vibrations caused by distortions or unevenness of the wheels 102a.

[0092] For this reason, they are more susceptible to vibration than general rotating electrical machines such as industrial motors, and are therefore required to have high resistance to vibration.

[0093] For these reasons, the conventional magnetic wedge holding structure only had sufficient magnetic wedge holding power, and there was a problem with long-term reliability.

[0094] In contrast, in the present embodiment, as described above, the magnetic wedge 10 can be held reliably for a long period of time, thereby reducing the risk of vibration or cracking of the magnetic wedge 10, allowing a highly efficient rotating motor 100 to be installed in the railway vehicle 200, and making it possible to reduce the power consumption of the railway vehicle 200. EXAMPLES

[0095] FIG. 13 shows a schematic configuration of a mobility device 300 that employs any one of the rotating electric machines 100 according to the first to sixth embodiments described above, as an eighth embodiment of the present invention.

[0096] As shown in FIG. 13, the mobility device 300 is roughly composed of a rotating electric machine 100, a wheel 102b that is rotated and driven by the rotating electric machine 100 via an axle 101b, and a mobility 105 that supports the rotating electric machine 100 via a support member 103b, and the rotating electric machine 100 is any one of the rotating electric machines 100 described in the above-mentioned Examples 1 to 6.

[0097] That is, the rotating electric machine 100 of the mobility device 300 is fixedly supported to the mobility 105 by a support member 103b, or is integrated with the wheel 102b and fixedly supported in a spring-loaded state. In either form, the rotor 2 of the rotating electric machine 100 is directly connected to the axle 101b, and the rotating electric machine 100 is configured to drive the wheel 102b via the axle 101b.

[0098] In addition, in any of the configurations, since the motor is subject to vibrations caused by the external environment such as the wheels 102b and the road surface environment, it is more susceptible to vibrations than general rotating electrical machines such as industrial motors, and is therefore required to have high resistance to vibrations.

[0099] For these reasons, the conventional magnetic wedge holding structure only had sufficient magnetic wedge holding power, and there was a problem with long-term reliability.

[0100] In contrast, in the present embodiment, as described above, the magnetic wedge 10 can be held reliably for a long period of time, thereby reducing the risk of vibration or cracking of the magnetic wedge 10, so that a highly efficient rotating motor 100 can be installed in the mobility device 300, and the power consumption of the mobility device 300 can be reduced.

[0101] This makes it possible to reduce CO2 emissions caused by the power consumption of the mobility device 300.

[0102] The mobility device 300 includes motorized vehicles such as EVs, HVs, and the like, and trains that use electric motors. Furthermore, the present invention is not limited to the above-described embodiments, and various modifications are included. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those having all of the configurations described. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration. [Explanation of symbols]

[0103] REFERENCE SIGNS LIST 1...frame, 2...rotor, 3...stator, 4a, 4b...bearing, 5...shaft, 6...stator teeth, 7...rotor core, 8...end ring, 9...stator core, 9a...groove, 9a1...circumferentially deepest part of groove, 10...magnetic wedge, 11...stator slot, 11a...slot opening, 12...conductor bar, 13...stator coil, 13a...stator coil end, 14...gap, 15...clearance, 15a...second Clearance, 16... varnish, 17... gap (space), 18... axial duct, 19... ventilation duct, 20, 20a... cushioning material, 20a1... multiple sheets of laminated insulating paper, 20a2... folded insulating paper, 100... rotating electric machine, 101a, 101b... axle, 102a, 102b... wheel, 103a, 103b... support member, 104... bogie, 105... mobility, 200... railway vehicle, 300... mobility device.

Claims

1. A rotating electric machine comprising a stator and a rotor disposed radially from the stator with a predetermined gap therebetween, the stator being composed of a stator coil and a stator core, the stator core being provided with stator slots for accommodating the stator coil, a slot opening being formed on the gap side of the stator slot, and a magnetic wedge for holding the stator coil being disposed in the slot opening, A rotating electric machine characterized in that the magnetic wedge is inserted into a groove on a side surface of the slot opening of the stator core, and a clearance is provided in the groove between the magnetic wedge and the stator core on the opposite gap side facing the circumferential end of the magnetic wedge, and the clearance is filled with varnish.

2. 2. The rotating electric machine according to claim 1, A rotating electric machine, characterized in that a difference in linear expansion coefficient between the stator core and the magnetic wedge is smaller than a difference in linear expansion coefficient between the stator core and the stator coil.

3. 3. The rotating electric machine according to claim 2, The rotating electric machine according to claim 1, wherein the magnetic wedge has a convex shape facing the gap side.

4. 3. The rotating electric machine according to claim 2, A rotating electric machine characterized in that the cross-sectional shape of the magnetic wedge is a trapezoid that is convex toward the gap side.

5. 5. The rotating electric machine according to claim 4, A rotating electric machine characterized in that the groove portion is formed in a stepped shape, the end of the magnetic wedge is inserted into the deepest circumferential point (deepest part) of the groove portion, and the stator core and the magnetic wedge are in contact at the deepest part.

6. 5. The rotating electric machine according to claim 4, A rotating electric machine characterized in that the groove portion is formed in a tapered shape, the end of the magnetic wedge is inserted into the deepest circumferential point (deepest part) of the groove portion, and the stator core and the magnetic wedge are in contact at the deepest part.

7. 5. The rotating electric machine according to claim 4, a second clearance is provided between the magnetic wedge and the stator coil, and the second clearance is filled with the varnish.

8. 5. The rotating electric machine according to claim 4, a second clearance is provided between the magnetic wedge and the stator coil, and a buffer member is disposed in the second clearance,

9. 5. The rotating electric machine according to claim 4, a second clearance is provided between the magnetic wedge and the stator coil, and a buffer member is disposed between the first clearance and the second clearance.

10. 10. A rotating electric machine according to claim 9, A rotating electric machine characterized in that the buffer member is made of a plurality of laminated insulating papers.

11. 10. A rotating electric machine according to claim 9, A rotating electric machine, characterized in that the buffer member is made of folded insulating paper.

12. A railway vehicle including a rotating electric machine, wheels that are rotationally driven by the rotating electric machine via axles, and a bogie that supports the rotating electric machine via a support member, A railway vehicle, wherein the rotating electric machine is the rotating electric machine according to any one of claims 1 to 11.

13. A mobility device including a rotating electric machine, a wheel that is rotationally driven by the rotating electric machine via an axle, and a mobility that supports the rotating electric machine via a support member, A mobility device, wherein the rotating electric machine is the rotating electric machine according to any one of claims 1 to 11.

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