JP5483862B2 - Rotating machine - Google Patents

Description

  The present invention relates to a rotating machine having a stator core and a stator outer frame, and more particularly to a technique for improving the efficiency of such a rotating machine.

  Generally, a rotating machine such as a motor includes a stator (stator) core, a rotor (rotor) core, and an outer frame for the stator that fixes the stator core. There are various methods for fixing the stator core to the outer frame for the stator. However, in a small electric induction machine or the like, it is common to fit the stator core to the outer frame for the stator with a squeeze. . There are methods such as “frozen”, “cooled”, and “press-fit” as the method of fitting, but the basic idea of each method is that the stator core has an inner diameter of the stator outer frame. By enlarging the outer diameter, after entering the outer frame for the stator, a tensile stress is generated in the outer frame for the stator, and a compressive stress is generated in the stator core to be fixed.

However, the compressive stress generated in the stator core at this time deteriorates the characteristics of the stator core and increases the iron loss, leading to a reduction in the efficiency of the rotating machine. Conventionally, in order to prevent a reduction in the efficiency of a rotating machine due to the compressive stress generated in such a stator core, for example, Patent Document 1 is provided with a hole for relaxing the stress generated in the stator core. A rotating machine has been proposed. Further, Patent Document 2 proposes a rotating machine in which a notch for reducing a compressive stress generated in the stator core is provided on the outer periphery of the stator core.
JP 2005-354870 A JP 2005-261158 A

  In conventional rotating machines, the efficiency of the rotating machine is reduced by providing holes in the stator core or by providing notches on the outer periphery of the stator core in order to reduce the compressive stress generated inside the stator core. It is preventing.

  However, if holes or notches are provided inside the stator core to suppress an increase in iron loss due to compressive stress, the flow of magnetic flux may be hindered depending on the location and shape of the holes and notches. In some cases, the efficiency of the rotating machine is deteriorated.

  In addition, the stator outer frame has a role of fixing the stator core, and also has a role of discharging heat generated inside the stator outer frame to the outside of the stator outer frame. The internal temperature of the rotating machine itself also decreases. As the temperature of the winding used inside the rotating machine decreases, the resistance decreases, leading to a reduction in copper loss generated inside the rotating machine, and the efficiency increases. For this reason, reducing the contact area between the stator core and the outer frame for the stator leads to a reduction in heat dissipation and causes deterioration in efficiency. In addition, the temperature rise inside the rotating machine shortens the life of each component used in the rotating machine, leading to product deterioration from the viewpoint of reliability.

  In view of the above problems, the present invention suppresses an increase in iron loss by reducing the compressive stress while keeping the magnetic flux flow optimal in the rotating machine, and without reducing the heat dissipation inside the rotating machine, The object is to provide an efficient rotating machine.

  In order to solve the above problems, the present invention relieves the compressive stress generated in the stator core by providing a notch in the circumferential direction of the inner peripheral surface of the stator outer frame. In addition, the portion where the stator core and the stator outer frame are not in contact with each other is filled with a high heat conduction member, thereby promoting the heat conduction from the stator core to the stator outer frame. By suppressing the temperature rise, a highly efficient rotating machine with suppressed loss increase is obtained.

  According to the present invention, in order to keep the flow of magnetic flux optimally in the rotating machine, a notch is added to the inner peripheral surface of the outer frame for the stator without changing the shape of the stator core, which occurs in the stator core. Reducing the compressive stress to suppress an increase in iron loss, and filling the cutout portion of the outer frame for the stator, that is, the gap between the stator core and the outer frame for the stator, with a high thermal conductivity member Thus, an efficient rotating machine can be provided without reducing the heat dissipation inside the rotating machine.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is an axial sectional view of a rotating machine in which a stator core 10 is contact-fixed to an outer frame 11 for a stator. A coil is wound around the stator core 10 to form a stator winding 13. When a current is supplied to the stator winding 13, a rotor (not shown) rotates. In this embodiment, the notch 12 is provided in the outer frame 11 for the stator, and both end portions of the stator core 10 are not in contact with the inner diameter of the outer frame 11 for the stator to form the gap 20. The compressive stress generated in 10 is reduced as compared with the case where all are in contact. As a result, an increase in iron loss generated in the stator core 10 is also suppressed, and a reduction in the efficiency of the rotating machine is suppressed.

  2 is an axial cross-sectional view of a rotating machine in which a gap 20 between the stator core 10 and the stator outer frame 11 is filled with a high heat conductive member 21 with respect to the rotating machine of FIG. In addition to the purpose of holding the stator core 10, the outer frame 11 for the stator discharges heat generated inside the rotating machine to the outside of the outer frame for the stator, thereby reducing the temperature inside the rotating machine. It also has the purpose of contributing to efficiency and long life. In FIG. 1 described above, the gap portion 20 between the stator core 10 and the stator outer frame 11 may deteriorate the heat dissipation of the heat generated inside the rotor, leading to a reduction in efficiency. Therefore, the gap portion 20 is filled with the high heat conductive member 21 to increase the heat dissipation, reduce the loss inside the rotating machine, and suppress the reduction of the rotating machine efficiency.

  As the high thermal conductive member 21, for example, a conductive silicon-containing resin sheet or a member in which a periphery of a high thermal conductive metal such as aluminum is covered with a resin can be used.

  3 is an axial sectional view of a rotating machine in which a fixing pin 30 is installed so as to penetrate the stator core 10 and the stator outer frame 11 with respect to the rotating machine of FIG. Since the contact area between the stator core 10 and the stator outer frame 11 is reduced, the force for holding the stator core is reduced, so that the holding force of the stator core is compensated by penetrating the fixing pin. is there. By providing the fixing pin 30 at the contact portion between the stator core 10 and the outer frame 11 for the stator, the holding force of the stator core 10 can be improved with a simple configuration, but the relative rotation between the two is restricted. If possible, it is not limited to this. Moreover, although the fixed location by the fixing pin 30 is one place in this figure, it does not interfere even if it is a multiple location. When a single fixing pin 30 is used, it is preferable to fix at the center of the contact portion between the stator core 10 and the stator outer frame 11.

  The rotating machine of FIGS. 4-6 reduces the contact area of the stator core 10 and the outer frame 11 for a stator with respect to the rotating machine of FIG. It is an axial sectional view of a rotating machine provided with a fixing pin 30 for holding a stator core 10. 1, the contact area between the stator core 10 and the stator outer frame 11 is reduced, so that the compressive stress generated in the stator core 10 is reduced, and the stator core 10 The iron loss that occurs is also reduced. In addition, since the gap 20 between the stator core 10 and the outer frame 11 for the stator is filled with the high heat conduction member 21, the heat dissipation of the heat generated inside the rotating machine is not deteriorated, and the efficiency is improved. Reduction can be suppressed and an efficient rotating machine can be provided.

構成内容Ａ（現状）では、固定子コアと固定子用外枠との間に空隙がなく、固定子コア全周において圧縮応力が発生し鉄損が増加し、効率の低下を招いている。全周において接触することにより、固定子用外枠への放熱性は良好であり、また固定子コアの空転防止の目的でも接触面積が大きい為、有効である。しかしながら、総合効率としての効果は少ない。 Table 1 summarizes the evaluation of the efficiency of a rotating machine positioned from the relationship between iron loss reduction, heat dissipation, stator core holding power, and iron loss and heat dissipation in each configuration.

In the configuration content A (current state), there is no gap between the stator core and the outer frame for the stator, compressive stress is generated around the entire circumference of the stator core, iron loss is increased, and efficiency is lowered. By contacting the entire circumference, heat dissipation to the outer frame for the stator is good, and the contact area is large for the purpose of preventing idling of the stator core, which is effective. However, the effect on the overall efficiency is small.

  In the configuration content B (known example), by arranging holes and notches in the stator core, the compressive stress generated in the stator core is reduced, and an increase in iron loss can be suppressed. However, by arranging holes or notches in the stator core, there is a possibility that the magnetic properties of the stator core may be deteriorated, and the heat dissipation from the stator core to the outer frame for the stator is deteriorated. Incurs a decline. Further, since the contact area is reduced, the effect as a detent of the stator core is also reduced. Although iron loss is somewhat improved, copper loss may be increased due to a decrease in heat dissipation, and the overall efficiency is less effective.

  The configuration content C (stack thickness 2/3) is 1/3 the length of the stator core stack thickness along the circumferential direction of the inner peripheral surface of the stator outer frame with respect to the configuration content A (current state). It is the structure where the notch part of this is arrange | positioned. In other words, 2/3 of the stator core thickness is in contact with the stator outer frame. This configuration content C is a structure intended to suppress the deterioration of the magnetic properties of the stator core with respect to the configuration content B (known example), and the effect is considered to be equivalent to the configuration content B. The stack thickness is the axial length of the stator core.

  The configuration content D (configuration content C + high heat conduction member) is a structure in which the gap between the stator core and the outer frame for the stator is filled with the high content heat conduction member with respect to the configuration content C. The overall efficiency is improved.

  For configuration content E (configuration content D + pin), the anti-rotation effect whose effect is reduced by the above configuration content B, C, D is arranged so that the fixing pin penetrates the stator core and the outer frame for the stator. By doing so, it is possible to prevent idling of the stator while maintaining efficiency, and the structure is effective as a rotating machine.

  The configuration content F (configuration content E + stack thickness 1/2) is less than the configuration content E by reducing the contact area between the stator core and the outer frame for the stator from 2/3 to 1/2. The increase can be further suppressed, and the heat dissipation is not deteriorated by filling the gap portion with a high heat conduction member, and the anti-spinning effect is provided by arranging the fixed pin, the overall efficiency is improved, and the effective rotating machine It is the composition.

  In the above-described embodiment, the rotating machine is described. However, the rotating machine is always generated for the rotating machine in which the stator core is held against the stator outer frame by shrink fitting or press fitting. Clearly it is a challenge. That is, it is apparent that the present invention can be applied to any rotating machine such as a brushless motor, an induction motor, and a DC motor as long as the rotating machine is used. Moreover, since the increase in the iron loss due to stress can be suppressed, the effect of improving the efficiency according to the present invention becomes larger as the ratio of the iron loss to the loss of the rotating machine is larger than the copper loss.

  7 to 9, the notch 12 of the stator outer frame 11 is installed in the axial direction, the stator core 10 is fitted, and the stator core 10 and the stator outer frame 11 are spaced from each other. This is a rotating machine in which the gap portion 20 is filled with a high heat conductive member 21.

  FIG. 8 shows a cross-sectional view taken along line C-C ′ of FIG. 7. FIG. 9 is a sectional view taken along line D-D ′ of FIG. 8. 7 to 9, the notch 12 is formed in the axial direction on the inner peripheral surface of the stator outer frame 11, and the notch between the stator core 10 and the stator outer frame 11 is formed. The high thermal conductive member 21 is filled in the gap 20 between the portions 12. As shown in FIG. 7, a fixing pin 30 for fixing may be provided.

  10-13, the notch part 12 of the outer frame 11 for stators is installed in both the axial direction and the circumferential direction, the stator core 10 is fitted, and the stator core 10 and the stator This is a rotating machine in which a gap portion 20 between the outer frame 11 and the cutout portion 12 is filled with a high heat conductive member 21.

  11 and 12 are cross-sectional views taken along lines E-E ′ and F-F ′ of FIG. 10, respectively. As shown in FIG. 11, in the cross section taken along the line EE ′, a plurality of cutout portions 12 are provided in the axial direction, and a plurality of cutout portions 12, 12,. .. Are filled with high heat conductive members 21, 21,...

  As shown in FIG. 12, in the cross section taken along the line FF ′, the notches 12 are provided on the entire circumference in the circumferential direction, and between the stator core 10 and the notches 12 of the stator outer frame. The high thermal conductive member 21 is filled in the gap portion.

  FIG. 13 is a cross-sectional view taken along line G-G ′ in FIG. 11. In Example 6 of FIGS. 10-13, the increase in a core loss can further be suppressed by further reducing the contact area of a stator core and the outer frame for stators.

FIG. 1 is an axial cross-sectional view of a rotating machine according to a first embodiment of the present invention in which a notch is provided along the circumferential direction of the inner peripheral surface of the stator outer frame. FIG. 2 is an axial cross-sectional view of the rotating machine according to the second embodiment of the present invention having a structure in which a high heat conductive member is embedded in a gap between the notch and the stator core along the circumferential direction. FIG. 3 is an axial cross-sectional view of a rotating machine according to a third embodiment of the present invention having a structure in which a fixing pin is driven so as to penetrate the stator core and the stator outer frame at the same time. FIG. 4 shows the axial direction of the rotating machine according to the fourth embodiment of the present invention in which a notch is provided in the outer frame for the stator, the space between the stator cores is filled with a high heat conductive member, and the fixing pin is driven. It is sectional drawing. FIG. 5 is a cross-sectional view taken along line A-A ′ of the rotating machine in FIG. 4. FIG. 6 is a cross-sectional view taken along line B-B ′ of the rotating machine in FIG. 4. FIG. 7 is a cross-sectional view of a rotating machine in which a notch portion of the stator outer frame is installed in the axial direction, and a gap between the stator core and the stator outer frame is filled with a high heat conductive member. 8 is a cross-sectional view taken along line C-C ′ of the rotating machine in FIG. 7. FIG. 9 is a cross-sectional view taken along line D-D ′ of the rotating machine in FIG. 8. FIG. 10 shows that the notch portion of the outer frame for the stator is installed in both the axial direction and the circumferential direction, and the gap between the stator core and the notch portion of the outer frame for the stator is filled with a high heat conduction member. It is the rotating machine of Example 5 of this invention. 11 is a cross-sectional view taken along line E-E ′ of the rotating machine in FIG. 10. FIG. 12 is a cross-sectional view taken along the line F-F ′ of the rotating machine in FIG. 10. 13 is a cross-sectional view taken along the line G-G ′ of the rotating machine in FIG. 11.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Stator core 11 Stator outer frame 12 Notch part 13 Stator winding 20 Cavity part 21 High heat conduction member 30 Fixing pin

Claims (2)

A stator core, a rotor core that rotates within the stator core, and a stator outer frame that fixes the stator core, and the stator core is fitted into the stator outer frame. In the rotating machine,
The outer frame for the stator has the same length in the axial direction and the same length in the axial direction at both ends in the axial direction at the portion where the stator core is fitted. horizontal notches is kept short than the axial length of the axial length of the stator for outer frame between the notch said stator core with provided, of the cutout portion and the stator core against The inner periphery of the part to be fitted has the same radius ,
In the gap between the notch and the stator core, a high thermal conductivity member is installed,
For the stator, the central part of the axial length of the fitting portion of the outer frame for the stator with the stator core matches the substantially central part of the axial length of the stator core. The outer frame and the stator core are fitted,
A rotating machine having a structure in which a fixing pin is driven so as to penetrate the stator core and a central portion of the stator outer frame at the same time. The rotating machine according to claim 1,
The rotating machine characterized in that an axial length of the stator outer frame between the notches is at least 1/2 or more of an axial length of the stator core.

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