JP6754207B2 - Armature manufacturing method - Google Patents

Description

The present invention relates to a method of manufacturing an armature including a permanent magnet.

An armature having a structure in which a permanent magnet is embedded inside a laminated iron core, such as a rotor of an IPM motor, is known. Since the permanent magnet is embedded in the rotor core of the IPM motor, the magnet does not pop out due to centrifugal force during the rotation of the motor, and the mechanical safety is high. Further, the IPM motor can obtain high efficiency and high torque. Therefore, the use of IPM motors has been rapidly expanding in recent years as a power source for automobiles, railroad vehicles, and other industries.

In many cases, the rotor constituting the IPM motor inserts a permanent magnet into each of the magnet insertion holes formed in the laminated iron core, and then injects resin into the magnet insertion holes to insert the resin into the magnet insertion holes. It is cured and the permanent magnet is fixed to the laminated iron core (Patent Documents 1 and 2). Patent Document 1 describes that after inserting a permanent magnet into a magnet insertion hole of a laminated iron core, the laminated iron core is heated, and then resin is injected into the magnet insertion hole (Nos. 0021 to 0025). Paragraph).

Further, a neodymium (neodymium) magnet is known as a permanent magnet embedded in a rotor constituting an IPM motor. Neodymium magnets have a high magnetic flux density and have a very strong magnetic force. Therefore, when neodymium magnets are embedded in a rotor, a small and powerful motor can be obtained.

Neodymium magnets are known to exhibit a positive coefficient of thermal expansion in the magnetization (easy) direction and a negative coefficient of thermal expansion in the non-magnetizing direction (direction orthogonal to the magnetization direction) (Patent Document 3 (0049th). Paragraph), Patent Document 4 (paragraph 0005)). That is, it is known that when a neodymium magnet is heated, the neodymium magnet expands in the magnetizing direction and contracts in the non-magnetizing direction.

The laminated iron core is a core obtained by punching a thin steel plate (called an "electromagnetic steel plate" based on its application or a "silicon steel plate" based on an alloy component) manufactured through a rolling process with a die. It is composed of laminated sheets. The core sheet that constitutes the rotor has a circular contour. The outline of the die that punches out the core sheet is also made into a perfect circle. However, even if the thin steel plate is punched out with a die having a perfect circular contour, the contour of the core sheet may become elliptical. That is, the core sheet may be distorted after punching.

For example, paragraph 0007 of Patent Document 5 states, "In a stator core sheet having a circular outer circumference, as shown in FIG. 9, the outer diameter dimension is large in the rolling direction of the electromagnetic steel plate, and the outer diameter dimension is large in the direction orthogonal to the rolling direction. On the contrary, the outer diameter dimension may be smaller in the rolling direction of the electromagnetic steel plate, and the outer diameter dimension may be larger in the direction orthogonal to the rolling direction. "

When a laminated iron core having a shape defect due to distortion of the core sheet is attached to the housing of a rotary electric machine, the housing is distorted. When the housing is distorted, various problems occur in the rotary electric machine. Further, when the laminated iron core having a defective shape is shrink-fitted into the housing and attached, a gap is formed between the laminated iron core and the housing in a part thereof. Therefore, the contact area between the laminated iron core and the housing becomes small. As a result, the fixing of the laminated iron core becomes insufficient, and the fixing of the laminated iron core may be lost to the torque generated by the rotary electric machine during high load operation, and the laminated iron core may rotate.

In the invention described in Patent Document 5, in order to solve the above problem, in the housing of the rotary electric machine, the position where the portion where the outer diameter dimension of the punched stator core sheet becomes larger than the normal dimension abuts is set to a non-fixed position. , The fixed position is the position where the part where the difference in outer diameter dimension from the regular dimension is small comes into contact.

According to the invention described in Patent Document 5, various problems caused by the mismatch between the shapes of the laminated iron core and the housing may be solved. However, the poor shape of the laminated iron core itself is not improved. Therefore, depending on the invention described in Patent Document 5, problems caused by poor shape of the laminated iron core, for example, problems of torque fluctuation and vibration caused by fluctuation of the gap (air gap) between the rotor and the stator. Is not resolved.

However, an invention aimed at suppressing the occurrence of shape defects in the laminated iron core has already been filed. For example, Patent Document 6 discloses a method for punching a non-oriented electrical steel sheet, which comprises controlling the roundness of the cutting edge of a punching die according to the elongation rate of the non-oriented electrical steel sheet. There is.

Japanese Unexamined Patent Publication No. 2014-138533 Japanese Unexamined Patent Publication No. 2014-220911 JP-A-2007-273850 Japanese Unexamined Patent Publication No. 2012-152869 JP-A-2009-112096 Japanese Unexamined Patent Publication No. 10-24333

According to Patent Document 6, the contour of the core sheet can be made a perfect circle by controlling the roundness of the cutting edge of the punching die. As a result, it is said that the shape defect of the laminated iron core is eliminated and the fluctuation of the output torque of the rotary electric machine is also eliminated. However, Patent Document 6 describes the roundness of the cutting edge of the punching die applied when punching a non-oriented electrical steel sheet containing Si: 4% or less and Al: 2% or less in weight%. The control formula is disclosed, but the control formula in other cases is not disclosed. Therefore, the invention described in Patent Document 6 has a problem that it can be applied when punching the above-mentioned non-oriented electrical steel sheet, but cannot be applied in other cases. That is, when a core sheet is manufactured by punching a steel plate other than the above-mentioned electromagnetic steel plate, the distortion of the core sheet cannot be eliminated by the invention described in Patent Document 6.

Therefore, in the invention described in Patent Document 6, with respect to the armature formed by laminating core sheets made of steel plates other than the above-mentioned electromagnetic steel plates, the shape defects are improved and various problems caused by the shape defects are solved. There is a problem that it cannot be solved.

The present invention has been made in view of such circumstances, and is a method for manufacturing an armature capable of improving the shape defect of the armature and solving various problems caused by the shape defect, and constitutes a laminated iron core. It is an object of the present invention to provide a highly versatile armature manufacturing method that can be applied regardless of the type of steel sheet to be used.

In the method for manufacturing an armature according to the present invention, a permanent magnet having a negative thermal expansion rate in the non-magnetizing direction is inserted into each of a plurality of magnet insertion holes formed in a laminated iron core, and then the magnet insertion holes are inserted. In the method of manufacturing an armature in which a resin is injected and cured in a magnet insertion hole to fix a permanent magnet to a laminated iron core , the permanent magnet is inserted into all of a plurality of magnet insertion holes provided in the laminated iron core. After that, the laminated iron core and the permanent magnet are heated, and when the laminated iron core is in a specific temperature range, resin is injected into a specific magnet insertion hole, and then another temperature range in which the laminated iron core is different from the specific temperature range. When it is in, the resin is injected into another magnet insertion hole.

After injecting the resin into the specific magnet insertion hole, the laminated iron core may be cooled so that the resin is injected into another magnet insertion hole when the temperature of the laminated iron core becomes lower than the specific temperature range. ..

Even if the resin is injected into a specific magnet insertion hole and then the laminated iron core is heated so that the resin is injected into another magnet insertion hole when the temperature of the laminated iron core becomes higher than the specific temperature range. good.

The specific magnet insertion holes may be a group of magnet insertion holes arranged in a direction forming a specific angle with respect to the rolling direction of the material of the laminated iron core.

The temperature of the laminated iron core may be changed each time the resin is injected into one magnet insertion hole, and then the resin may be injected into another magnet insertion hole.

When the temperature of the laminated iron core is in the range of 120 ° C. to 200 ° C., the resin may be injected into the magnet insertion hole.

According to the present invention, it is possible to correct a shape defect of an armature configured by embedding a permanent magnet inside a laminated iron core. As a result, in the rotary electric machine provided with the armature, the occurrence of problems such as torque fluctuation is suppressed, and the performance of the rotary electric machine is improved.

It is a top view which shows the structure of the armature manufacturing apparatus used in the armature manufacturing method which concerns on embodiment of this invention. It is a front view which shows the structure of the preheating device provided in the armature manufacturing apparatus shown in FIG. It is a front view which shows the structure of the resin sealing apparatus included in the armature manufacturing apparatus shown in FIG. It is a block diagram of the laminated iron core which concerns on embodiment of this invention, FIG. 4A is a plan view of the laminated iron core, and FIG. 4B is a side view of the laminated iron core. It is explanatory drawing which shows the manufacturing method of the base plate which comprises the laminated iron core which concerns on embodiment of this invention. It is explanatory drawing which shows the manufacturing method of the armature which concerns on embodiment of this invention, and is the top view of the laminated iron core. It is explanatory drawing which shows another example of the manufacturing method of the armature which concerns on embodiment of this invention, and is the top view of the laminated iron core. In the embodiment of the present invention, it is explanatory drawing which shows the principle that the strain of a laminated iron core is corrected, and FIGS. 8 (a)-(d) 8 (a)-(d) show the process of correcting the strain of a laminated iron core in chronological order. It is a figure which shows.

Hereinafter, a method for manufacturing an armature according to an embodiment of the present invention will be described in detail with reference to the drawings.

(manufacturing device)
FIG. 1 is a plan view showing a configuration of an armature manufacturing apparatus 1 according to an embodiment of the present invention. As shown in FIG. 1, the manufacturing apparatus 1 includes a conveyor 2, a preheating apparatus 3, and a resin sealing apparatus 4. Further, the manufacturing apparatus 1 includes a computer 100, and the transfer conveyor 2, the preheating device 3, and the resin sealing device 4 are controlled by the computer 100 to operate.

(Conveyor)
The conveyor 2 is an apparatus for carrying the laminated iron core 6 manufactured in an upstream process (not shown) arranged on the left side of the manufacturing apparatus 1 in FIG. 1 into the manufacturing apparatus 1. The laminated iron core 6 that has been processed in the manufacturing apparatus 1 is carried out by the conveyor 2 to a downstream process (not shown) arranged on the right side of the manufacturing apparatus 1 in FIG.

The laminated iron core 6 carried into the manufacturing apparatus 1 from the upstream process is transferred from the transport conveyor 2 to the preheating device 3 by a transfer device (not shown). The preheating device 3 is a device that heats the laminated iron core 6 to raise the temperature of the preheating device 3 to a predetermined temperature. The detailed configuration of the preheating device 3 will be described later.

The laminated iron core 6 that has been heated in the preheating device 3 is returned to the transfer conveyor 2, and is transferred from the transfer conveyor 2 to the resin sealing device 4 by another transfer device (not shown). In the resin sealing device 4, resin is injected and filled into the laminated iron core 6. The laminated iron core 6 for which the resin filling is completed is taken out from the resin sealing device 4, returned to the transport conveyor 2, and carried out to a downstream process (not shown). The detailed configuration of the resin sealing device 4 will be described later.

(Preheating device)
As shown in FIG. 2, the preheating device 3 includes a lower heating unit 31 on which a transport tray 5 on which the laminated iron core 6 is placed is placed, and a fixed pedestal 32 fixed to the installation location. An elevating means (for example, a jack) 33 for raising and lowering the lower heating portion 31 up and down is fixed to the fixed pedestal 32. Further, the preheating device 3 includes an upper heating portion 34 located above the laminated iron core 6 (indicated by a broken line in FIG. 2) raised to the upper limit position by the elevating means 33, and a side surrounding the laminated iron core 6 from the side. It has a part heating part 35. The side heating portion 35 is divided into two in the horizontal direction, and the divided portions can be opened and closed by moving the divided portions in the horizontal direction (indicated by arrows in FIG. 2) around the laminated iron core 6. .. Further, electric heaters (not shown) are provided in the heating units 31, 34, and 35 provided in the preheating device 3, and the laminated iron core 6 is heated by the electric heaters. Further, as described above, the preheating device 3 operates under the control of the computer 100.

(Resin sealing device)
As shown in FIG. 3, the resin sealing device 4 includes a lower mold 41 on which the transport tray 5 on which the laminated iron core 6 is placed is placed, and an upper mold 42 on which the laminated iron core 6 is placed. ing. Further, a dummy plate 7 is sandwiched between the laminated iron core 6 and the upper mold 42. That is, the lower surface of the dummy plate 7 is in contact with the upper surface of the laminated iron core 6, and the upper surface of the dummy plate 7 is in contact with the lower surface of the upper mold 42. The dummy plate 7 is a kind of cover that prevents the resin material 8 injected from the upper mold 42 into the magnet insertion hole 61 of the laminated iron core 6 from spreading on the upper surface of the laminated iron core 6 and adhering to the upper surface of the laminated iron core 6. Is. The dummy plate 7 is also called a cal plate.

The upper mold 42 includes the same number of resin injection ports 43 as the magnet insertion holes 61 included in the laminated iron core 6. That is, the resin injection port 43 is arranged in the upper mold 42 so as to correspond one-to-one with the magnet insertion hole 61 provided in the laminated iron core 6. Each resin injection port 43 penetrates the upper mold 42 up and down.

A resin injection port 71 is provided at a portion of the dummy plate 7 that comes into contact with the resin injection port 43 of the upper die 42. The resin material 8 filled in the magnet insertion hole 61 is injected into the magnet insertion hole 61 in a molten liquid state through the resin injection port 43 of the upper mold 42 and the resin injection port 71 of the dummy plate 7. Ru. A permanent magnet 9 is inserted into each magnet insertion hole 61 in the upstream process. The resin material 8 injected into the magnet insertion hole 61 is cured in the magnet insertion hole 61, and the permanent magnet 9 is fixed in the magnet insertion hole 61.

A plunger 44 is attached to each resin injection port 43. The plunger 44 is a member that is supplied from a resin supply device (not shown) and pushes out the resin material 8 held in the resin injection port 43 toward the magnet insertion hole 61. The plunger 44 is driven by an actuator (not shown). Further, the plurality of plungers 44 (actuators (not shown) for driving the resin sealing device 4) are controlled by the computer 100 and operate all at once, individually, or in groups. Therefore, the resin sealing device 4 can simultaneously inject and fill all the magnet insertion holes 61 included in the laminated iron core 6 with the resin material 8. Further, the resin sealing device 4 can individually inject and fill the resin material 8 into all the magnet insertion holes 61 included in the laminated iron core 6 at different timings. Further, the resin sealing device 4 can divide all the magnet insertion holes 61 included in the laminated iron core 6 into a plurality of groups, and inject and fill the resin material 8 in each group at different timings.

(Laminated iron core)
Next, the configuration and structure of the laminated iron core 6 will be described. The laminated iron core 6 is a component that constitutes an armature of a rotary electric machine (for example, a rotor of an IPM motor), and is configured by laminating a plurality of base plates 10 as shown in FIG. 4 (b). .. Further, as shown in FIG. 4A, 16 magnet insertion holes 61 are formed in the laminated iron core 6. The magnet insertion holes 61 are arranged on the circumference centered on the center of the laminated iron core 6. As described above, the permanent magnet 9 is inserted into the magnet insertion hole 61, and the permanent magnet 9 is fixed to the laminated iron core 6 by the resin material 8 filled in the magnet insertion hole 61. Further, a shaft hole 62 penetrating the laminated iron core 6 is formed at the center of the laminated iron core 6. A rotating shaft of a rotating electric machine (not shown) is inserted into the shaft hole 62.

As shown in FIG. 5, the base plate 10 constituting the laminated iron core 6 is formed by punching from a strip-shaped blank 11. The blank 11 is manufactured by a rolling mill (not shown) and is supplied to the manufacturing process of the base plate 10 in the form of a coil wound into a roll. Then, the blank 11 is pulled out from a coil (not shown), transferred from left to right in FIG. 5, and sequentially processed. That is, in the first step, the magnet insertion hole 61 is punched out from the blank 11, and then the blank 11 is transferred to the second step. In the second step, the shaft hole 62 is punched from the blank 11, and then the blank 11 is transferred to the third step. In the third step, the outer ring 63 is punched from the blank 11, and in the fourth step, the base plate 10 is separated from the blank 11. As described above, since the blank 11 is pulled out from the coil wound in a roll shape, the longitudinal direction of the blank 11 (left-right direction in FIG. 5) coincides with the rolling direction of the blank 11. Further, in the step of laminating the base plates 10, the base plates 10 are laminated in the same direction so that the rolling directions of the base plates 10 face the same direction. That is, in FIG. 4A, when the base plate 10 on the uppermost layer of the laminated iron core 6 is placed so that the rolling direction is in the left-right direction of FIG. 4A, all the elements constituting the laminated iron core 6 are formed. The plate 10 is placed so that the rolling direction is the left-right direction shown in FIG. 4A.

(First Embodiment)
Next, a method of manufacturing an armature according to the first embodiment of the present invention will be described with reference to FIG. FIG. 6 is a plan view of the laminated iron core 6. In FIG. 6, each of the 16 magnet insertion holes 61 is attached with subscripts a, b, .... P to distinguish each of the magnet insertion holes 61.

In the first embodiment, the 16 magnet insertion holes 61a, 61b, ... 61p are divided into two groups. That is, the magnet insertion holes 61a, 61d and the magnet insertion holes 61i, 61l are the first group. The magnet insertion holes 61e, 61h and the magnet insertion holes 61m, 61p are the second group. As shown in FIG. 6, the magnet insertion holes 61 belonging to the first group are arranged in a direction parallel to the rolling direction of the base plate 10 constituting the laminated iron core 6. The magnet insertion holes 61 belonging to the second group are arranged in a direction orthogonal to the rolling direction of the base plate 10 constituting the laminated iron core 6.

In the first embodiment, first, the laminated iron core 6 is heated to 180 ° C. or higher in the preheating device 3. Then, the laminated iron core 6 is carried into the resin sealing device 4 and the temperature of the laminated iron core 6 is measured. The means for measuring the temperature of the laminated iron core 6 is arbitrary. The lower die 41 or upper die 42 of the resin sealing device 4 may be provided with a contact-type temperature sensor such as a thermocouple, or a non-contact such as an infrared radiation thermometer may be provided around the resin sealing device 4. A type of temperature sensor may be provided. Then, when the temperature of the laminated iron core 6 reaches 180 ° C., the resin material 8 is injected into the magnet insertion holes 61 (61a, ... 61d and 61i, ... 61l) belonging to the first group. When the injection of the resin material 8 into the magnet insertion hole 61 belonging to the first group is completed, the laminated iron core 6 is naturally cooled. Then, when the temperature of the laminated iron core 6 reaches 170 ° C., the resin material 8 is injected into the magnet insertion holes 61 (61e, ... 61h and 61m, ... 61p) belonging to the second group. When the injection of the resin material 8 into the magnet insertion hole 61 belonging to the second group is completed, the laminated iron core 6 is naturally cooled. When the laminated iron core 6 is cooled and the resin material 8 injected into the magnet insertion hole 61 is cured, the laminated iron core 6 is carried out from the resin sealing device 4.

The heating target of the laminated iron core 6 in the preheating device 3 is a resin sealing device for the laminated iron core 6 from the preheating device 3 at a temperature (180 ° C.) at which the resin material 8 is injected into the magnet insertion hole 61 belonging to the first group. It is a value obtained by adding a temperature drop that occurs during transportation to 4 as a margin. That is, when the laminated iron core 6 is heated to 180 + α ° C. in the preheating device 3, α corresponds to the temperature drop that occurs while the laminated iron core 6 is transported from the preheating device 3 to the resin sealing device 4.

(Second embodiment)
The method for manufacturing an armature according to the present invention is not limited to the method in which 16 magnet insertion holes 61 are divided into two groups and the resin material 8 is injected into each group under different temperature conditions. The 16 magnet insertion holes 61 may be divided into three or more groups, and the resin material 8 may be injected into each group under different temperature conditions. Therefore, in the second embodiment, as shown in FIG. 7, the 16 magnet insertion holes 61 are divided into three groups. That is, the magnet insertion holes 61b, 61c, 61j, 61k are the first group, the magnet insertion holes 61d, 61e, 61h, 61i, 61l, 61m, 61p, 61a are the second group, and the magnet insertion holes 61f, 61g, 61n, 61o. Is the third group.

Then, the laminated iron core 6 is heated to 180 ° C. or higher in the preheating device 3. After that, the laminated iron core 6 is carried into the resin sealing device 4 and the temperature of the laminated iron core 6 is measured. When the temperature of the laminated iron core 6 reaches 180 ° C., the resin material 8 is injected into the magnet insertion holes 61 (61b, 61c, 61j, 61k) belonging to the first group. When the injection of the resin material 8 into the magnet insertion hole 61 belonging to the first group is completed, the laminated iron core 6 is naturally cooled. Then, when the temperature of the laminated iron core 6 reaches 160 ° C., the resin material 8 is injected into the magnet insertion holes 61 (61d, 61e, 61h, 61i, 61l, 61m, 61p, 61a) belonging to the second group. When the injection of the resin material 8 into the magnet insertion hole 61 belonging to the second group is completed, the laminated iron core 6 is naturally cooled. Then, when the temperature of the laminated iron core 6 reaches 140 ° C., the resin material 8 is injected into the magnet insertion holes 61 (61f, 61g, 61n, 61o) belonging to the third group. When the laminated iron core 6 is cooled and the resin material 8 injected into the magnet insertion hole 61 is cured, the laminated iron core 6 is carried out from the resin sealing device 4. The heating target of the laminated iron core 6 in the preheating device 3 is also the temperature (180 ° C.) at which the resin material 8 is injected into the magnet insertion hole 61 belonging to the first group, and the laminated iron core 6 is resin-sealed from the preheating device 3. It is a value obtained by adding a temperature drop that occurs during transportation to 4 as a margin.

(Correction of poor shape)
Finally, with reference to FIG. 8, the principle that the shape defect of the laminated iron core 6 is corrected by the method according to the first and second embodiments will be described. FIG. 8A is a plan view showing the shapes of the magnet insertion hole 61 and the permanent magnet 9 of the laminated iron core 6 at room temperature. The permanent magnet 9 is a neodymium magnet, and its magnetization easy performance differs depending on the direction. In each figure of FIG. 8, the X-axis shows the magnetized (easy) axis of the permanent magnet 9, and the Y-axis shows the non-magnetized axis of the permanent magnet 9. That is, the permanent magnet 9 is arranged in the magnet insertion hole 61 so that the magnetized (easy) axis coincides with the X axis and the non-magnetized axis coincides with the Y axis. Further, the neodymium magnet, that is, the permanent magnet 9, has a positive coefficient of thermal expansion in the magnetization axis (X-axis) direction and a negative coefficient of thermal expansion in the non-magnetization axis (Y-axis) direction. .. Therefore, when the permanent magnet 9 is heated, the permanent magnet 9 expands in the X-axis direction and contracts in the Y-axis direction.

FIG. 8B is a plan view showing the shapes of the magnet insertion hole 61 and the permanent magnet 9 when the laminated iron core 6 is heated. In this case, the magnet insertion hole 61 expands in the X-axis and Y-axis directions (the dimension expands). The permanent magnet 9 expands (dimensions) in the X-axis direction and contracts (dimensions) in the Y-axis direction. As a result, the gap between the magnet insertion hole 61 and the permanent magnet 9 is expanded. In particular, the gap in the Y-axis direction expands.

When the resin material 8 is injected into the magnet insertion hole 61 while the laminated iron core 6 is heated in this way, as shown in FIG. 8C, the resin is formed in the gap between the magnet insertion hole 61 and the permanent magnet 9. The material 8 is filled.

After injecting the resin material 8 into the magnet insertion hole 61, the laminated iron core 6 is cooled to return the temperature of the laminated iron core 6 to room temperature, and the resin filled in the gap between the magnet insertion hole 61 and the permanent magnet 9 is filled. The material 8 is cured. At this time, the magnet insertion hole 61 contracts in the X-axis and Y-axis directions (dimensions are reduced). The permanent magnet 9 contracts (reduces in size) in the X-axis direction and expands (increases in size) in the Y-axis direction. That is, the magnet insertion hole 61 and the permanent magnet 9 try to return to the shape shown in FIG. 8A. However, as shown in FIG. 8D, since the resin material 8 is filled in the gap between the magnet insertion hole 61 and the permanent magnet 9, the dimension of the magnet insertion hole 61 in the Y-axis direction is the original dimension ( It does not return to the dimensions shown in FIG. 8A). The magnet insertion hole 61 is pressed from the inside by the permanent magnet 9 and the resin material 8 in the Y-axis direction. Therefore, the dimension of the magnet insertion hole 61 in the Y-axis direction is enlarged. As a result, the laminated iron core 6 is also deformed in the direction of expanding the dimension in the Y-axis direction around the magnet insertion hole 61. The thick solid line with an arrow in FIG. 8D indicates the pressing force acting on the magnet insertion hole 61 at this time.

Further, the difference in the dimensions of the laminated iron core 6 in the Y-axis direction in the state shown in FIG. 8 (d) with respect to the state shown in FIG. It changes depending on the temperature. If the temperature of the laminated iron core 6 when the resin material 8 is injected is set to a relatively high temperature, the gap between the magnet insertion hole 61 and the permanent magnet 9 in the state shown in FIG. 8B becomes large. Therefore, the amount of the resin material 8 injected into the magnet insertion hole 61 increases. Then, in the state shown in FIG. 8D, the thickness of the resin material 8 filled in the gap in the Y-axis direction between the magnet insertion hole 61 and the permanent magnet 9 increases. As a result, the magnet insertion hole 61 and the laminated iron core 6 are greatly expanded in the Y-axis direction.

On the other hand, if the temperature of the laminated iron core 6 when the resin material 8 is injected is lowered, the temperature between the magnet insertion hole 61 and the permanent magnet 9 in the state shown in FIG. 8 (b) is higher than that in the case of raising the temperature. The gap becomes smaller. Therefore, the amount of the resin material 8 injected into the magnet insertion hole 61 is reduced. Then, in the state shown in FIG. 8D, the thickness of the resin material 8 filled in the gap in the Y-axis direction between the magnet insertion hole 61 and the permanent magnet 9 is reduced. As a result, the amount of expansion of the dimensions of the magnet insertion hole 61 and the laminated iron core 6 in the Y-axis direction becomes small.

By adjusting the temperature of the laminated iron core 6 when the resin material 8 is injected in this way, the dimensions of the magnet insertion hole 61 and the laminated iron core 6 generated after the injected resin material 8 is cured in the Y-axis direction. The amount of enlargement can be adjusted. Then, by utilizing this phenomenon, it is possible to correct the shape defect of the laminated iron core 6. That is, the temperature of the laminated iron core 6 is greatly increased to inject the resin material 8 into the magnet insertion hole 61 at the position where the dimension in the Y-axis direction is desired to be greatly expanded, and the resin material 8 is injected into the other magnet insertion holes 61. The shape of the laminated iron core 6 can be modified by injecting the resin material 8 at a relatively low temperature of the laminated iron core 6.

In the first embodiment, the magnet insertion hole 61 belonging to the first group has a relatively large size in the Y-axis direction after the resin material 8 is cured. The amount of expansion of the dimension of the magnet insertion hole 61 belonging to the second group in the Y-axis direction after the resin material 8 is cured is smaller than that of the magnet insertion hole 61 belonging to the first group. Also in the second embodiment, the magnet insertion hole 61 belonging to the first group has a relatively large size in the Y-axis direction after the resin material 8 is cured. The amount of expansion of the magnet insertion hole 61 belonging to the second group in the Y-axis direction after curing of the resin material 8 is the amount of expansion of the dimension of the magnet insertion hole 61 after curing of the resin material 8 in the Y-axis direction. The first group is the largest, the second group is the second, and the third group is the smallest.

As described above, according to the embodiment of the present invention, it is possible to correct the shape defect of the armature formed by embedding the permanent magnet 9 inside the laminated iron core 6. As a result, in the rotary electric machine provided with the armature, the occurrence of problems such as torque fluctuation is suppressed, and the performance of the rotary electric machine is improved. Further, the method for manufacturing an armature according to the above embodiment can be applied regardless of the type of steel plate constituting the laminated iron core.

However, the technical scope of the present invention is not limited by the above embodiments. The present invention can be freely modified, applied or improved within the scope of the technical ideas described in the claims.

For example, the unit for changing the temperature of the laminated iron core 6 when the resin material 8 is injected is not limited to the “group of magnet insertion holes 61”. The temperature of the laminated iron core 6 may be changed for each magnet insertion hole 61 to inject the resin material 8. Further, the number of magnet insertion holes 61 forming the "group" is also arbitrary.

Further, in the first embodiment, as specific examples of the "direction forming a specific angle with respect to the rolling direction of the material of the laminated iron core 6," the "direction parallel to the rolling direction of the base plate 10" and the "elementary plate 10". The direction orthogonal to the rolling direction of the plate 10 ”is exemplified. However, the "direction forming a specific angle" is not limited to the "parallel direction" and the "orthogonal direction". The "specific angle" can be arbitrarily selected.

In the above embodiment, the manufacturing apparatus 1 is provided with the preheating device 3 separately from the resin sealing device 4, but the preheating device 3 may be integrally configured with the resin sealing device 4. For example, a heat source may be attached to the resin sealing device 4 so that the laminated iron core 6 can be heated while the laminated iron core 6 is attached to the resin sealing device 4.

In the above embodiment, an example is shown in which the preheating device 3 is provided with an electric heater as a heat source for heating the laminated iron core 6. However, the heat source included in the preheating device 3 and the heat source included in the resin sealing device 4 when the preheating device 3 and the resin sealing device 4 are integrally configured are not limited to the electric heater. The heat source may be one that heats the laminated iron core 6 by induction heating or hot air. Alternatively, the heat source may be one that heats the laminated iron core 6 by combining any two or more of heating by an electric heater, induction heating, and heating by hot air.

In the above embodiment, in the resin sealing device 4, the resin material 8 is injected into the magnet insertion hole 61 while cooling the laminated iron core 6. That is, when the laminated iron core 6 is in a specific temperature range, the resin material 8 is injected into the specific magnet insertion hole 61, and then the laminated iron core 6 is cooled so that the laminated iron core 6 is lower than the specific temperature range. An example of injecting the resin material 8 into another magnet insertion hole 61 when the temperature reaches the above temperature range is shown. However, the technical scope of the present invention is not limited to such objects. The resin material 8 may be injected into the magnet insertion hole 61 while heating the laminated iron core 6. For example, when the resin sealing device 4 is provided with a heat source for heating the laminated iron core 6, when the laminated iron core 6 is in a specific temperature range, the resin material 8 is injected into a specific magnet insertion hole 61, and then the laminated iron core 6 is provided. 6 may be heated so that the resin material 8 is injected into another magnet insertion hole 61 when the laminated iron core 6 reaches another temperature range higher than the specific temperature range.

In the first embodiment, when the temperature of the laminated iron core 6 is 180 ° C., the resin material 8 is injected into the magnet insertion hole 61 belonging to the first group, and when the temperature of the laminated iron core 6 is 170 ° C. An example of injecting the resin material 8 into the magnet insertion hole 61 belonging to the second group is shown. In this case, 180 ° C. corresponds to "a specific temperature range" and 170 ° C. corresponds to "another temperature range". Further, in the second embodiment, when the temperature of the laminated iron core 6 is 180 ° C., the resin material 8 is injected into the magnet insertion hole 61 belonging to the first group, and the temperature of the laminated iron core 6 is 160 ° C. An example is shown in which the resin material 8 is sometimes injected into the magnet insertion hole 61 belonging to the second group, and the resin material 8 is injected into the magnet insertion hole 61 belonging to the third group when the temperature of the laminated iron core 6 is 140 ° C. It was. In this case, 180 ° C. corresponds to "a specific temperature range", 160 ° C. corresponds to "a specific temperature range" or "another temperature range", and 140 ° C. corresponds to "another temperature range". However, the "specific temperature range" and the "other temperature range" are not limited to these. "Specific temperature range" and "another temperature range" can be arbitrarily selected and set. However, if the temperature of the laminated iron core 6 is too high, the resin material 8 injected into the magnet insertion hole 61 may be deteriorated. If the temperature of the laminated iron core 6 is too low, the fluidity of the resin material 8 injected into the magnet insertion hole 61 decreases, which is not preferable. Therefore, it is desirable to select and set the "specific temperature range" and the "other temperature range" in the range of 120 ° C. to 200 ° C.

In the above embodiment, an example in which the "specific temperature range" and the "other temperature range" are set pinpointly such as 180 ° C., 170 ° C., or 140 ° C. is shown, but the present invention pinpoints the "temperature range". It is not limited to what is set by points. The "temperature range" may be set by an upper limit or a lower limit, or may be set by an upper limit and a lower limit.

In the above embodiment, a neodymium magnet is exemplified as a specific example of a "permanent magnet having a negative coefficient of thermal expansion in the non-magnetizing direction", but a "permanent magnet having a negative coefficient of thermal expansion in the non-magnetizing direction" is a neodymium magnet. Is not limited. The present invention is widely applied in the manufacture of armatures comprising "permanent magnets having a negative coefficient of thermal expansion in the non-magnetizing direction" that are present or will emerge in the future.

In the above embodiment, the rotor of the IPM motor has been exemplified as a specific example of the armature, but the armature to which the present invention is applied is not limited to the rotor of the IPM motor. The armature to which the present invention is applied may be a stator, or may be a rotor or a stator provided in a motor other than an IPM motor. Further, the armature to which the present invention is applied is not limited to the armature constituting the electric motor. The present invention is also applied to the manufacture of armatures constituting a generator.

1 Manufacturing equipment 2 Conveyance conveyor 3 Preheating equipment 4 Resin encapsulation equipment 5 Conveyance tray 6 Laminated iron core 7 Dummy plate 8 Resin material 9 Permanent magnet 10 Base plate 11 Blank 31 Lower heating unit 32 Fixed stand 33 Lifting means 34 Upper heating unit 35 side Part Heating part 41 Lower type 42 Upper type 43 Resin injection port 44 Plunger 61 Magnet insertion hole 61a, ... 61p Magnet insertion hole 62 Shaft hole 63 Outer ring 71 Resin injection port 100 Computer

Claims (6)

A permanent magnet having a negative thermal expansion coefficient in the non-magnetizing direction is inserted into each of the plurality of magnet insertion holes formed in the laminated iron core, and then resin is injected into the magnet insertion holes to insert the magnet insertion holes. In the method of manufacturing an armature in which the permanent magnet is fixed to the laminated iron core by curing in the inside.
When the permanent magnet is inserted into all of the plurality of magnet insertion holes provided in the laminated iron core, and then the laminated iron core and the permanent magnet are heated to bring the laminated iron core into a specific temperature range. The resin is injected into the specific magnet insertion hole,
Then, when the laminated iron core is in a different temperature range different from the specific temperature range, the resin is injected into the other magnet insertion hole.
How to make an armature. After injecting the resin into the specific magnet insertion hole, the laminated iron core is cooled, and when the laminated iron core reaches a temperature lower than the specific temperature range, the resin is placed in another magnet insertion hole. Characterized by injecting,
The method for manufacturing an armature according to claim 1. After injecting the resin into the specific magnet insertion hole, the laminated iron core is heated, and when the laminated iron core reaches a temperature higher than the specific temperature range, the resin is inserted into another magnet insertion hole. Characterized by injecting,
The method for manufacturing an armature according to claim 1. The specific magnet insertion holes are a group of the magnet insertion holes arranged in a direction forming a specific angle with respect to the rolling direction of the material of the laminated iron core.
The method for manufacturing an armature according to any one of claims 1 to 3. Each time the resin is injected into one magnet insertion hole, the temperature of the laminated iron core is changed, and then the resin is injected into another magnet insertion hole.
The method for manufacturing an armature according to any one of claims 1 to 3. When the temperature of the laminated iron core is in the range of 120 ° C. to 200 ° C., the resin is injected into the magnet insertion hole.
The method for manufacturing an armature according to any one of claims 1 to 5.

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