JP4562093B2 - Rotating electric machine and method of manufacturing rotating electric machine - Google Patents

Description

  The present invention relates to a rotating electrical machine and a method for manufacturing the rotating electrical machine, and in particular, has little deterioration in characteristics due to stress of the stator of the rotating electrical machine, can suppress electrical loss, and has excellent electrical efficiency.

  A conventional rotating electrical machine has a “shrink fit” method as a process for accommodating a stator of the rotating electrical machine in a frame. “Shrink fit” heats the outer part, expands the hole, and fits the inner part outside, shrinking as the temperature of the outer part decreases to room temperature, the inner one Is a method of tightening at the contact surface and fastening both. There is a manufacturing method called “cold fitting” based on the exact same principle. This is a method of cooling the inner side and fitting it inside the outer side. In either case, the frame and the stator are fastened using the force with which the frame tends to contract. These methods can apply uniform stress to the direction of the rotation axis of the stator, and have been used for a long time.

  However, recent research has revealed that the compressive stress applied to the stator during the above-mentioned “shrink fitting” and “cold fitting” deteriorates the electromagnetic properties of the magnetic steel sheet material of the stator, and is particularly important as a magnetic path. In the vicinity of the inner peripheral side of such a stator, it is strongly desired that no compressive stress remains during manufacturing. This is because the deterioration of the electromagnetic properties increases the thermal loss when the rotating electrical machine is driven. In order to solve this problem, an example is shown in which the abutting portion of the stator is shifted from the portion corresponding to the outer angle of the substantially polygonal shape (see, for example, Patent Document 1).

JP-A-2005-130552

  The conventional rotating electric machine has a problem in that strong stress is generated in an inner portion important as a magnetic path of the stator, particularly in a portion corresponding to an outer angle of a substantially polygon on the inner peripheral surface of the stator. When the magnetic properties of the magnetic steel sheet of the stator deteriorate due to stress, the magnetic permeability, which is the reciprocal of the magnetic resistance, decreases, and the iron loss, that is, thermal loss increases. This has the problem that the efficiency of the rotating machine is lowered, in other words, the power consumption of the electric product is increased.

  The present invention has been made in order to solve the above-described problems. The rotating electric machine and the rotating machine have excellent electrical efficiency and are capable of suppressing electrical loss to a low level with little deterioration in characteristics due to the stress of the stator of the rotating electric machine. It aims at providing the manufacturing method of an electric machine.

  In the present invention, a rotor having a rotation shaft is opposed to an inner circumferential surface side through a radial gap portion and a plurality of teeth are formed on the inner circumferential surface side at predetermined intervals in the circumferential direction. In a rotating electrical machine comprising a stator, a stator coil formed by winding a conductive wire around each tooth multiple times, and a frame covering the outer peripheral surface of the stator, a surface perpendicular to the rotation axis on the outer peripheral surface side of the stator A concave portion that is recessed in the direction of the rotation axis is formed at a location including the center position in the circumferential direction between the teeth on the top, and two locations sandwiching the circumferential recess between the teeth on the surface perpendicular to the rotation axis, and The frame fastening portion provided on the inner peripheral surface side of the frame and the frame fastening portion provided on the outer peripheral surface side of the stator at a position where the interval in the circumferential direction of the two places is ½ or less of the predetermined interval between the teeth. Each stator fastening part to be Is, the stator fastening part and the frame fastening portion is intended to stress so as to sandwich the circumferential direction is fitted to the stator and the frame is fastened acting between the teeth of the recess of the stator.

  In the rotating electrical machine of the present invention, a rotor having a rotating shaft is opposed to the inner peripheral surface side via a radial gap portion and a plurality of teeth are provided on the inner peripheral surface side at predetermined intervals in the circumferential direction. In a rotating electrical machine comprising a stator to be formed, a stator coil formed by winding a conductive wire around each tooth, and a frame covering the outer peripheral surface of the stator, a rotating shaft on the outer peripheral surface side of the stator A concave portion that is recessed in the direction of the rotation axis is formed at a location that includes the center position in the circumferential direction between the teeth on the vertical surface, and two locations that sandwich the circumferential concave portion between the teeth on the surface that is perpendicular to the rotation axis. In addition, the frame fastening portion provided on the inner peripheral surface side of the frame and the outer peripheral surface side of the stator are provided at positions where the circumferential interval between the two locations is equal to or less than ½ of the predetermined interval between the teeth. The stator fastening part that fastens with the frame fastening part Since the stator fastening portion and the frame fastening portion are respectively formed and fastened by stress acting so that the concave portion of the stator is sandwiched between the teeth in the circumferential direction, the frame and the stator are fitted together. Since the compressive stress applied to the central position between the teeth on the inner peripheral surface side of the stator that forms a magnetic path is reduced, there is little electromagnetic loss, that is, power consumption can be kept low.

Embodiment 1 FIG.
Embodiments of the present invention will be described below. 1 is a diagram showing a configuration of a rotating electrical machine according to Embodiment 1 of the present invention, and particularly shows a state before shrinkage fastening, and is a part of a cross section perpendicular to a rotation axis. 2 is a diagram showing a stator fastening portion and a frame fastening portion of the configuration of the rotating electrical machine shown in FIG. 1, and particularly shows a state after shrinkage fastening, and FIG. 3 is a shrinkage fastening in the rotating electrical machine shown in FIG. FIG. 4 is a diagram showing the distribution of stress after the operation, FIG. 4 is a diagram showing the distribution of stress after the shrinkage fastening in another rotating electrical machine, and FIG. 5 is a diagram for explaining the contraction fastening of the rotating electrical machine shown in FIG. FIG. In the figure, the rotating electrical machine has a rotor 105 having a rotating shaft 100 and an inner peripheral surface facing the rotor 105 via a radial gap 106 and a plurality of teeth 103 on the inner peripheral surface side in the circumferential direction. The stator 101 is formed at a predetermined interval H1, the stator coil 51 is formed by winding the conductive wire 50 around each tooth 103, and the frame 102 covers the outer peripheral surface of the stator 101. Here, the predetermined interval H1 where the teeth 103 are formed refers to the interval between the teeth center line L1 and the teeth center line L2 of the adjacent teeth 103.

  Further, a recess 20 is formed at a location including the circumferential center position 104 between the teeth 103 on the outer peripheral surface side of the stator 101, and the circumferential direction between the teeth 103 on the surface perpendicular to the rotation shaft 100 of the rotor 105 is formed. At two locations sandwiching the recess 20 and at a position where the circumferential interval between the two locations becomes an interval H2 that is ½ or less of the predetermined circumferential interval H1 between the teeth 103, on the inner peripheral surface side of the frame 102 A frame fastening portion 22 provided and a stator fastening portion 21 provided on the outer peripheral surface side of the stator 101 and fastened to the frame fastening portion 22 are formed. The stator fastening portion 21 and the frame fastening portion 22 are fastened by a stress X that causes the concave portion 20 of the stator 101 to be sandwiched between the teeth 103 in the circumferential direction, and the frame 102 and the stator 101 are fitted. ing. The interval H2 equal to or less than ½ of the predetermined interval H1 mentioned here indicates a length equal to or less than ½ of the predetermined interval H1 between the teeth center lines L1 and L2, which are the stator fastening portion 22 and the frame fastening portion. 22 is set with reference to positions L3 and L4 on the center position 104 side.

  The stator fastening portion 21 and the frame fastening portion 22 can be formed by, for example, machining or die molding. Here, the fastening surfaces of the stator fastening portion 21 and the frame fastening portion 22 are substantially the same. The stator fastening portion 21 is formed by a substantially semicircular fastening recess that is recessed in the direction of the rotation axis 100 so as to have a semicircular shape, and the frame fastening portion 22 is a substantially semicircle that is fastened to the stator fastening portion 21. It is formed by a fastening projection that protrudes in the direction of the rotational axis 100 of the shape. The stator fastening portion 21, the frame fastening portion 22, and the recessed portion 20 are formed at all locations between the teeth 103.

  Next, the operation of the first embodiment configured as described above will be described. In this relationship, when shrinkage fastening is performed by shrink fitting or cold fitting between the stator 101 and the frame 102, the contraction force of the frame fastening portion 22 provided on the frame 102 causes the space between the stator fastening portions 21 of the stator 101. This member also acts as a contraction force. Note that when a method using thermal shrinkage due to a temperature difference such as “shrink fitting” or “cool fitting” is used, this temperature difference is usually set to about 100 degrees. At this time, due to the presence of the concave portion 20 between the stator fastening portions 21 provided in the stator 101, stress X (action point) acts on the stator 101 in a “leverage principle”, and the stress X is a fulcrum. Stress Y (power point) acts as Z. Therefore, a low tensile stress acts on the portion of the center position 104 corresponding to the outer angle of the substantially polygon L on the inner peripheral surface of the stator 101. Since this position is a flow path of the magnetic flux of the stator coil 51 formed by the winding 50, it is important to lower the magnetic resistance. Compared to a conventional rotating electric machine in which the magnetic resistance is increased by compressive stress, the magnetic resistance is reduced. There is little loss, that is, power consumption can be reduced.

  The action of the tensile stress will be described with reference to FIGS. 3 and 4 of the stress simulation. This stress simulation is a stress contour level diagram as a result of calculation of the stress state applied to the stator 101 as the frame 102 is cooled. The stress value is shown as the Mises equivalent stress value that is most often used as the stress of metal. The value was normalized by the maximum stress value in the calculation area. In this case, the stress distribution (contour level) is indicated by contour lines from 1.00 where the stress is strongly received to 0.10 where the stress is low. FIG. 3 is a result of stress simulation on the stator 101 in the shape of the inner peripheral surface of the frame 102 according to the first embodiment of the present invention. FIG. 4 is different from the present invention and FIG. 4 shows the stator fastening portion 21 and the frame of the present invention. The stator fastening part 210 and the frame fastening part 220 corresponding to the fastening part 22 are formed at intervals of 1/2 or more of the predetermined spacing between the teeth 103, and the recess 200 between the stator fastening part 210 and the frame fastening part 220 is formed. FIG. 6 is a diagram showing the results of a stress simulation applied to the stator 101 in the shape of the inner peripheral surface of the frame 102 when forming. Each figure shows only half of the teeth 103 protruding in the direction of the rotation axis 100 from the stator 101 by utilizing the geometric symmetry in the plane perpendicular to the rotation axis 100 of the stator 101 and the frame 102. .

  As is clear from FIG. 4, when different from the present invention, the stator 101 receives the contraction fastening force from the frame 102 to fit the frame 102 and the stator 101, but the teeth 103 are virtually connected to the stator 101. It can be seen that a strong compressive stress is generated at the center position 104 corresponding to the outer angle of the substantially polygon L of the inner circumferential surface of the stator obtained when the removal is performed. On the other hand, as apparent from FIG. 3, in the present invention, the stator 101 receives the contraction fastening force from the frame 102, so that the frame 102 and the stator 101 are fitted, but the teeth 103 are virtually connected to the stator 101. It can be seen that almost no compressive stress is generated at the central position 104 corresponding to the outer angle of the substantially polygonal L of the inner circumferential surface of the stator obtained when it is removed.

  Moreover, in this Embodiment 1, the rotary electric machine with which the fastening surface of the stator fastening part 21 and the frame fastening part 22 is a substantially semicircle shape is shown. The stator 101 in contact with the frame 102 is formed so that the shape of the stator fastening portion 21 has a substantially semicircular shape, and the shape of the frame fastening portion 22 of the opposing frame 102 also has a substantially semicircular shape. It is processed as follows. Thus, when the frame 102 and the stator 101 are separated from each other due to the temperature difference, that is, when the state of FIG. 5A is shifted to the state of FIG. Even if the center L22 is slightly displaced in the circumferential direction with respect to the center L21 of the stator fastening portion 21, the fastening surfaces of the stator fastening portion 21 and the frame fastening portion 22 are substantially semicircular. As shown in FIG. 5B, the center L22 and the center L21 are overlapped with each other while causing slippage relatively, and contraction fastening at a desired position can be performed.

  Further, although there is no particular description about the fastening allowance of each stator fastening portion 21 and the frame fastening portion 22, for example, it is formed so that there is almost no fastening allowance on the A portion side near the recess 20, and the B portion side far from the recess 20. Then, if it is formed so as to have a larger fastening allowance than the part A side, the stress on the A part side close to the recessed part 20 is stronger than that on the B part side when fastening each stator fastening part 21 and the frame fastening part 22. In addition, the compressive stress at the central position 140 can be further reduced.

  According to the first embodiment configured as described above, a strong compressive stress is applied to the outer peripheral portion of the stator due to the contraction of the frame, and the central position between the teeth of the inner peripheral portion of the stator, which is important as a magnetic circuit, is low. It can be in a stress state or a tension state. Therefore, the deterioration of the magnetic characteristics of the magnetic steel sheet of the stator is prevented, leading to a reduction in magnetic loss, that is, an improvement in motor efficiency. In addition, since the fastening surfaces of the frame fastening portion and the stator fastening portion are formed in a substantially semicircular shape, the frame fastening portion of the frame and the stator fastening portion of the stator are not baked in a state where they are not completely matched. Even when fitting or cooling fitting is performed, the frame fastening portion and the stator fastening portion can be matched while the frame and the stator slide relative to each other in the circumferential direction.

  In the first embodiment, an example in which the center of the concave portion is formed at a substantially central position of the central position is shown. However, if the concave portion is formed in such a positional relationship as the central position, the first embodiment is described. Needless to say, the same effect can be achieved. Moreover, although the example which forms a fastening convex part as a frame fastening part in a frame and a fastening recessed part as a stator fastening part in a stator was shown, it is not restricted to this, a frame fastening part is formed as a fastening recessed part, and it fixes Even if the child fastening portion is formed as a fastening convex portion fastened by the frame fastening portion, the same effect can be obtained. Furthermore, in the first embodiment, the example in which the frame fastening portion, the stator fastening portion, and the recess are linearly formed in parallel to the rotation axis is shown, but the present invention is not limited to this. It suffices if it is formed in a cross section perpendicular to the rotation axis, and does not need to be formed through the rotation axis.

Embodiment 2. FIG.
6, 7 and 8 are cross-sectional views showing the configurations of the stator fastening portion and the frame fastening portion of the rotating electric machine according to Embodiment 2 of the present invention. In addition, in each figure, only the structure of the stator fastening part and frame fastening part different from the said Embodiment 1 is demonstrated. In addition, since other portions are the same as those in the first embodiment, description thereof will be omitted as appropriate, and other portions will be described with reference to FIG. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted. First, in Embodiment 2 of the present invention, the stator fastening portion is formed by a fastening recess that is recessed in the direction of the rotation axis, and the frame fastening portion is urged against and abuts on both side walls of the fastening recess. It shows about what is formed by the fastening convex part which protrudes in the direction.

  As an example, as shown in FIG. 6, a stator fastening portion 24 composed of a rectangular groove-like fastening recess recessed in the rotation axis direction on the outer peripheral surface of the stator 101, A frame fastening portion 25 which is fastened to the stator fastening portion 24 on the peripheral surface side, is urged against both side walls of the stator fastening portion 24 and abuts and protrudes in the direction of the rotation axis, and has a plate spring shape. It is composed of. First, from the state before fastening shown in FIG. 6 (a), by inserting the frame fastening part 25 into the stator fastening part 24 as shown in FIG. 6 (b), the leaf spring shape of the frame fastening part 25 is The stator fastening portion 24 is urged against and brought into contact with both side walls of the fastening concave portion and fastened.

  According to the rotating electric machine of the second embodiment formed as described above, the frame fastening portion is inserted into the stator fastening portion due to the principle of the leaf spring, so that compressive stress is applied in the circumferential direction. As a reaction, the frame fastening portion tries to open, and this acts as a force that pushes both side walls of the stator fastening portion in the circumferential direction. Therefore, as in the first embodiment, the center position between the teeth of the inner peripheral portion of the stator, which is important as a magnetic circuit, can be in a low stress state or a tensile state. Further, this can be achieved with a simple shape called a leaf spring shape.

  As another example, as shown in FIG. 7, the frame is formed of a fastening convex portion that is fastened to the stator fastening portion 24 and protrudes in the rotation axis direction and the rotation axis opposite direction on the inner peripheral surface side of the frame 102. A fastening portion 26 and a clamping jig portion 27 that is fitted and fastened to a portion of the frame fastening portion 26 protruding in the direction opposite to the rotation axis are provided. Then, as shown in FIG. 7 (a), the frame fastening portion 26 is inserted into the stator fastening portion 24, and then, as shown in FIG. 7 (b), a portion that protrudes to the outer peripheral side of the frame fastening portion 26 By fitting the clamping jig portion 27 into the flange, the projecting portion on the inner peripheral side of the frame fastening portion 26 is urged against and abutted on both side walls of the stator fastening portion 24 and fastened.

  According to the rotating electrical machine of the second embodiment formed in this way, for example, after the stator and the frame are temporarily fixed with a low temperature difference in shrinkage fastening in a state where there is almost no fastening allowance, the rotating shaft of the frame fastening portion Covering the protruding part of the frame fastening part in the opposite direction of the rotation axis of the frame fastening part with a method such as press-fitting, with respect to the part protruding in the opposite direction, the holding jig part having a width narrower than that width is applied. The portion projecting in the direction of the rotation axis serves as a force that pushes both side walls in the circumferential direction against the stator fastening portion, and can fix the stator and the frame. Therefore, as in the first embodiment, the center position between the teeth of the inner peripheral portion of the stator, which is important as a magnetic circuit, can be in a low stress state or a tensile state. In addition, since it is possible to finally fix with the clamping jig portion even if the fastening allowance between the stator and the frame is not strictly formed, the manufacture of the frame fastening portion and the stator fastening portion becomes simple. .

  As another example, as shown in FIG. 8, a frame fastening portion 28 is provided on the inner peripheral surface side of the frame 102. The frame fastening portion 28 is a fastening convex portion that is fastened to the stator fastening portion 24 and protrudes in the rotation axis direction. The frame fastening portion 28 is formed in a pressing shape formed by pressing against the stator fastening portion 24 from the outer peripheral side of the frame 102 by the pressing jig 29. Therefore, as shown in FIG. 8A, the frame fastening portion 28 is pressed against the stator fastening portion 24 from the outer peripheral side of the frame 102 by the holding jig 29, and finally, as shown in FIG. 7B. In addition, the protruding portion of the frame fastening portion 28 having a pressing shape in the rotational axis direction is urged against and abutted on both side walls of the stator fastening portion 24 and fastened.

  According to the rotary electric motor of Embodiment 2 formed in this way, a substantially circular frame is fitted on the outer periphery of the stator, and then the frame is recessed from the outer peripheral side of the frame using a pressing jig, Caulking to the stator fastening portion of the stator with a frame fastening portion having a pressing shape. Therefore, as in the first embodiment, the center position between the teeth of the inner peripheral portion of the stator, which is important as a magnetic circuit, can be in a low stress state or a tensile state. In addition, the frame fastening portion can be easily manufactured, and hence the stator fastening portion can be easily manufactured.

Embodiment 3 FIG.
FIG. 9 is a diagram showing a configuration of a rotating electrical machine according to Embodiment 3 of the present invention. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. The third embodiment of the present invention differs from the above embodiments in that the stator 101 is divided. The split portion 107 of the stator 101 is between the two rotor fastening portions 21 formed between the teeth 103 and is directed from the inner peripheral surface side of the stator 101 toward the outer peripheral surface side of the stator 101. Are divided and formed. A stress X from the frame fastening portion 22 and the stator fastening portion 21 that is generated by fastening the frame fastening portion 22 and the stator fastening portion 21 is applied to the divided portion 107 and is pushed in the circumferential direction. Therefore, the accuracy of the shape is maintained.

  The rotating electrical machine of the third embodiment configured as described above has the same effects as those of the above-described embodiments, but the stator is divided efficiently by fastening the frame fastening portion and the stator fastening portion. Since it is often held in the circumferential direction, the machining accuracy is improved and the gap between the divided portions is reduced. Thereby, the harmonics generated by the unbalance of the gaps between the divided portions can be suppressed.

  In each of the above embodiments, an example in which the concave portion, the stator fastening portion, and the frame fastening portion are all formed between the teeth has been described. However, the present invention is not limited to this, and the concave portion is formed only between some teeth. If the stator fastening portion and the frame fastening portion are formed, the compressive stress concentration at the center position between the teeth on the inner peripheral side of the corresponding stator is eliminated, and the same effects as those in the above embodiments can be obtained. Moreover, in each said embodiment, although the example which forms all the stator fastening parts and a frame fastening part by the same shape between each tooth | gear was shown, actually the shape of a stator fastening part and a frame fastening part Is formed with some variation depending on the location between each tooth to prevent the occurrence of coking torque.

It is the figure which showed the structure of the rotary electric machine in Embodiment 1 of this invention. It is a figure which shows the structure of the stator fastening part and frame fastening part of the rotary electric machine shown in FIG. It is the figure which showed distribution of the stress after shrinkage fastening in the rotary electric machine shown in FIG. It is the figure which showed distribution of the stress after shrinkage fastening in another rotary electric machine. It is a figure for demonstrating the shrinkage | contraction fastening of the rotary electric machine shown in FIG. It is sectional drawing which showed the structure of the stator fastening part and frame fastening part of the rotary electric machine in Embodiment 2 of this invention. It is sectional drawing which showed the structure of the stator fastening part and frame fastening part of the rotary electric machine in Embodiment 2 of this invention. It is sectional drawing which showed the structure of the stator fastening part and frame fastening part of the rotary electric machine in Embodiment 2 of this invention. It is the figure which showed the structure of the rotary electric machine in Embodiment 3 of this invention.

Explanation of symbols

20 recesses, 21, 24, 210 stator fastening parts,
22, 25, 26, 28, 220 Frame fastening part, 50 windings, 51 stator coil,
100 rotating shaft, 101 stator, 102 frame, 103 teeth,
104 center position, 105 rotator, 106 gap, 107 split location,
H1 predetermined interval, L1, L2 teeth center line.

Claims (6)

A rotor having a rotating shaft and a stator in which an inner peripheral surface is opposed to the rotor via a radial gap and a plurality of teeth are formed on the inner peripheral surface at predetermined intervals in the circumferential direction. And a stator coil formed by winding the conductive wire around each of the teeth a plurality of times, and a frame that covers the outer peripheral surface of the stator, and is perpendicular to the rotating shaft on the outer peripheral surface side of the stator A recess that is recessed in the direction of the rotation axis is formed at a location including a center position in the circumferential direction between the teeth on a smooth surface, and the recess in the circumferential direction between the teeth on a surface perpendicular to the rotation axis is sandwiched The frame fastening portion provided on the inner peripheral surface side of the frame and the fixing at the two positions and the position where the circumferential distance between the two positions is ½ or less of the predetermined distance between the teeth. Provided on the outer peripheral side of the child The stator fastening portion that is fastened to the frame fastening portion is formed, and the stator fastening portion and the frame fastening portion are fastened by stress acting so as to sandwich the concave portion of the stator between the teeth in the circumferential direction. And the frame and the stator are fitted together. The shape of the said frame fastening part and the said stator fastening part is comprised so that the fastening surface of the said frame fastening part and the said stator fastening part may become a substantially semicircular shape. Rotating electric machine. A fastening projection formed by a fastening recess formed by the stator fastening portion being recessed in the rotation axis direction, and the frame fastening portion being urged against and in contact with both side walls of the fastening recess and projecting in the rotation axis direction The rotating electrical machine according to claim 1, wherein The said fastening convex part is formed in the shape of a leaf | plate spring, or is formed in the press shape formed by pressing with respect to the said fastening recessed part from the outer peripheral side of the said frame. The rotating electrical machine according to 3. 2. The stator according to claim 1, wherein when the stator is divided and formed, the divided portion of the stator is formed between the two rotor fastening portions formed between the teeth. The rotating electrical machine according to any one of claims 4 to 4. The method for manufacturing a rotating electrical machine according to any one of claims 1 to 5, wherein the fitting of the frame and the stator is performed by either a shrink fitting method or a cold fitting method. .

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