JPH037045A - Manufacture of electrical rotary machine - Google Patents

Abstract

PURPOSE:To eliminate abrasive finishing work by compression molding magnetic powder mixed with binder in a groove formed in the rotor or stator casing and forming a permanent magnet having profile conformable to the shape of the groove. CONSTITUTION:A groove 36 is made in the end face of a casing 31 at the side of a permanent magnet, and a yoke member 33 composed of soft magnetic material is arranged in the groove 36. Then mixture of magnetic powder and thermosetting resin binder is injected into the groove 36 and the mixture material is compression molded to form a mold magnet 57, thereafter the binder is hardened. Then the mold magnet 57 is magnetized such that a plurality of magnetic poles having alternating polarities are produced in the circumferential direction on the pole face 58 at the open end side of the groove 36. By such arrangement, a permanent magnet having profile conformable to the shape of the groove can be formed and since the permanent magnet can be assembled as it is, abrasive finishing work of the permanent magnet can be eliminated resulting in cost reduction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a rotating power machine such as an electric motor or a generator.

(Prior Art) Conventionally, rotary power machines such as electric motors have been commercialized as single units. Therefore, when driving the rotation of a cross-flow fan in an indoor unit of an air conditioner, a separate electric motor such as an AC induction motor is required. This requires space to accommodate the inside of the device, which has the disadvantage of increasing the size of the device. Therefore, in recent years, attempts have been made to downsize the device by employing a DC brushless morph as the electric motor. A specific example of such a device is, for example, Japanese Unexamined Patent Publication No. 1986-
41696, and in that device, a substantially cup-shaped casing of a rotor is connected to a side plate of a fan rotor of a cross flow fan, and a permanent The magnet is configured to surround the outer periphery of the stator.

By the way, in the so-called outer row type motor in which 6 two rotors surround the outer periphery of the stator as described above, the shape of the rotor is large and therefore the weight is large, so the axis misalignment with the fan rotor may occur. There is a problem in that large vibrations occur even when a small amount of vibration occurs. Therefore, it is conceivable to adopt a so-called axial gap type motor configuration in which the rotor and stator face each other in the axial direction.

In this case, the rotor has a rotor configuration in which, for example, a ring-shaped yoke and a permanent magnet are sequentially arranged on the end face of the fan rotor, and the rotor can be made smaller in shape and therefore lighter in weight. The generation of vibration can be reduced.

(Problems to be Solved by the Invention) Incidentally, as the above permanent magnet, a sintered body of a magnetic material such as ferrite is usually used. Since such a sintered body of magnetic material is highly hard and brittle, finishing to a shape with a predetermined thickness is performed by polishing, which raises the problem of high manufacturing costs. In addition, if the magnetic pole surface of the permanent magnet facing the stator is configured to be flat, and the gap between it and the stator, that is, the air gap is uniform over the entire circumference, the rotation During driving, for example, cogging becomes large, causing a problem that good rotational performance cannot be obtained. That is, when one salient pole of the stator core is located at a position facing the boundary area of different poles adjacent in the circumferential direction of the permanent magnet, the opposite poles of the permanent magnet adjacent to each other are This is because leakage magnetic flux increases between the two, and this leakage magnetic flux acts as a force that tries to stop rotation. This type of cogging causes the magnetic pole surface of the permanent magnet to have an uneven shape, and the air gap between the stator and the boundary area between adjacent different poles is larger than the air gap at the center area of each magnetic pole. This can be reduced by configuring as follows. However, when polishing the magnetic pole face of a permanent magnet into a shape different from a flat surface, the manufacturing cost becomes even higher.

The present invention has been made in view of the above, and an object thereof is to provide a method for manufacturing a rotating power machine that can reduce manufacturing costs and improve characteristics.

(Means for Solving the Problems) Therefore, the method for manufacturing a rotating power machine according to the first aspect of the present invention is such that the magnetic pole portions of the rotor 3 and the stator 4 are made to face each other in the axial direction, and the rotor 3 and a stator 4, the magnetic pole part of one 3 of the rotary electric machine is made of a permanent magnet 32, and the casing 31 on the side where the permanent magnet 32 is provided is made of a non-magnetic material. At the same time, an annular recessed groove 36 is formed in the end face of this casing 31, and a yoke member 33 made of a soft magnetic material is disposed on the bottom surface 38 side of this recessed groove 36, and then magnetic powder and heat are disposed. Is the mixed material with a binder made of curable resin etc. indented? 1436, and then the mixed material is compression-molded to form a molded magnet 57, the binder is hardened, and then the magnetic pole surface of the molded magnet 57 on the open end side of the recessed groove 36 is injected into the molded magnet 57. At 58, the magnet molded body 57 is magnetized so that a plurality of magnetic poles that are alternately different in the circumferential direction are generated.

Further, in the method for manufacturing a rotary power machine according to the second claim, in the method for manufacturing a rotary power machine according to the first claim, a boundary region of different poles adjacent to each other in the circumferential direction on the magnetic pole surface 5th A magnet molded body 57 having a recessed shape closer to the bottom surface 38 of the recessed groove 36 than the central region of the magnetic pole is formed by compression molding the mixed material.

The method for manufacturing a rotary power machine according to the third claim is the method for manufacturing a rotary power machine according to the first or second claim, in which a magnet is formed on the circumferential side of the recessed groove 36 toward the open end side. In order to prevent the body 57 from being pulled out, an engaging part 37 having a surface that intersects with the pulling out direction is provided, and the molded magnet body 57 having a circumferential side along the engaging part 37 is formed by compression molding the mixed material. Further, the method for manufacturing a rotary power machine according to the fourth claim is the method for manufacturing a rotary power machine according to the first, second or third claim, in which the recessed groove 36 is formed in the yoke member 33. In addition to providing a penetration part 41 that penetrates from the open end side to the bottom side,
A recessed hole 40 is formed in the bottom surface 38 of the recessed groove 36 at a location where the through-hole 41 is located, and a protrusion 56 is inserted into the through-hole 4I and the recessed hole 40 by compression molding of the mixed material. A magnet molded body 57 having a shape is formed by compression molding the mixed material, and the casing 3
1, the yoke member 33, and the magnet molded body 57 are prevented from idling.

(Function) In the method for manufacturing a rotating power machine according to the first aspect, a mixed material of magnetic powder and a binder is compression-molded in the recessed groove 3G of the casing 31 of the rotor 3 or stator 4. , a magnet molded body 57 that follows the shape of this recessed groove 36
is formed and configured as a permanent magnet 32 that is assembled into the casing 31 as it is. Therefore, polishing and finishing of the permanent magnet, which was necessary in the past, is no longer necessary.

Further, in the method for manufacturing a rotating electric machine according to the second aspect, the air gap at the boundary area of adjacent different poles is larger than the air gap at the center area of each magnetic pole on the magnetic pole surface of the permanent magnet 32. It is also formed in a shape that increases in size, thereby making it possible to reduce cogging in, for example, an electric motor. The shape of the magnetic pole face 58 of the permanent magnet 32, which can improve the characteristics as described above, is such that it does not need to be polished and finished.
It is formed during compression molding of the mixed material within the recessed groove 36 of the casing 31.

Further, in the method for manufacturing a rotating power machine according to the third aspect, the structure for preventing the permanent magnet 32 from coming out of the recessed groove 36 further includes: The idling prevention structure between the casing 31, the yoke member 33, and the permanent magnet 32 is provided in the casing 3, respectively.
It is formed during compression molding of the mixed material in the recessed groove 36 of I, and there is no need for parts or additional processing to prevent slippage or idle rotation.

(Example) Next, a specific example of the method for manufacturing a rotating electric power machine of the present invention will be described in detail with reference to the drawings.

FIG. 2 is an assembled cross-sectional view of the main parts of a cross-flow fan installed in an indoor unit of an air conditioner. Rotor 3 in fan drive motor
A stator 4 is disposed at a position facing the rotor 3 in the axial direction.

First, the configuration on the stator 4 side will be explained.

The stator 4 is composed of an iron core 5 made of laminated electrical iron plates and a coil 6 wound around the iron core 5.
As shown in FIGS. 3 and 4, the iron core 5 includes a ring-shaped portion 7 on the axis side, and six magnetic path portions 8 extending radially outward from the ring-shaped portion 7. 8 and each magnetic path section 8.
- The stator magnetic pole part 9 is formed by bending the wide part on the tip side of the stator pole part 8 at a right angle to the axial direction.

As shown in FIG. 2, in order to fix the stator 4, which is constructed by winding the coils 6...6 around each of the magnetic path sections 8...8, into the indoor unit of the air conditioner,
A cylindrical stator housing 11 surrounding the outer periphery of the stator 4 and a fixed case 13 further surrounding the outer periphery of the stator housing 11 and fixed to the frame 12 of the indoor unit are provided. The stator 4 is fixed in the stator housing 11 by press-fitting the outer circumferential side of the stator magnetic pole part 9 along the inner circumferential surface of the cylindrical part of the stator housing 11 on the fan rotor 1 side, and The above-mentioned fixed case 1
3, the stator housing 11 is assembled by pressing the outer periphery of the stator housing 11, and the stator 4 is inserted into the indoor unit.

The side of the stator housing 11 opposite to the fan rotor l is formed to have a rectangular cross section, and a stepped portion is provided between the stator housing 11 and the cylindrical portion of the fan rotor. The stator magnetic pole part 9 is formed without bending the other end.
It is constructed by further laminating copper plates that protrude outward from the base plate, and the protrusion is assembled so that the protrusion comes into contact with the stepped portion.

This provides a structure for preventing movement of the stator 4 in the axial direction when a magnetic attraction force is applied from the permanent magnets 32 of the rotor 3, which will be described later.

The inner space of the rectangular section of the stator housing 11 is configured as a control circuit component storage chamber, and a circuit board 15 having a DC brushless morph control circuit is disposed within this space. On this circuit board 15, in addition to the power transistor 16, electronic components such as a capacitor, a resistor, and a control IC are mounted, although not shown.

Further, a heat sink 17 is disposed facing the circuit board 15, and the heat sink of the power transistor 16, which generates a large amount of heat, is attached in close contact with the heat sink 17.

On the other hand, there is a bearing 1 inside the axial center through hole of the stator 4.
A ring-shaped bearing case 19 made of an elastic material such as synthetic rubber and housing the bearing case 8 is attached by press-fitting the small diameter portion on the right end side thereof.

Furthermore, a Hall element 21 is disposed at a radially inward position near the tip surface of the stator magnetic pole part 9, and the rotor 3 rotational position is detected.

Next, the configuration of the rotor 3 will be explained.

As shown in FIG. 2, the rotor 3 includes a substantially disk-shaped casing 31 fixed along the side plate 2 of the fan rotor l, and a casing 31 facing the stator magnetic pole portion 9 inside the casing 31. The permanent magnet 32 is disposed at a position opposite to the stator 4, and a yoke member 33 forms a magnetic path for the permanent magnet 32 on the side opposite to the stator 4.

5 and 6 show the shape of the casing 31. As shown in FIG. This casing 31 is a component made of a non-magnetic material such as a synthetic resin material, and has an axial center hole 34 formed at the axial center position, and an end face 3 of the four stators.
A recessed groove 36 having a substantially rectangular cross section in the axial direction is formed on the outer circumferential side of 5 along a circumference concentric with the axial center.

An engagement groove 37 that is recessed inward in the radial direction is further formed at a midway position on the circumferential surface of the recessed groove 36 on the radially inner circumferential side, and the bottom surface 38 of the recessed groove 36 is , recessed holes 40 . . . 40 that are further recessed from the bottom surface 38 to the end surface 39 side of the two side plates are bored at each point dividing the same circumference into four equal parts.

On the other hand, FIG. 7 and FIG. 8 show the shape of the yoke member 33, and this yoke member 33 has the shape of the recessed groove 3.
It is a ring-shaped part having an outer circumferential diameter and an inner circumferential diameter that are approximately the same size as 6, and is placed at a position corresponding to each of the above-mentioned recessed holes 40 . . . Small through holes 41...41 are bored. After arranging this yoke member 33 on the bottom surface 38 side of the recessed groove 36,
The permanent magnet 32 is formed in this recessed groove 36, and the manufacturing procedure will be explained below.

First, as shown in
Align the circumferential position of each recessed hole 40 . . . 40 and each through hole 41 . Next, a predetermined amount of a paste-like mixed material prepared by mixing magnetic powder, which will be described later, with, for example, a thermosetting epoxy resin as a binder, is injected into the recessed groove 36 .

As shown in FIG. 1, the casing 3I
is placed in a compression molding mold to perform compression molding of the mixed material. In FIG. 1, 51 is the lower mold of the compression molding die, and after the casing 31 is installed in the recess 52 inside the lower mold 51, the upper mold 5 of the compression molding mold is
3 into the recess 52 and pressurized downward in the figure.

The upper mold 53 has the casing 31 at its lower end.
A molded part 54 having the same cross-sectional shape as the opening shape of the recessed groove 36 is provided, so that the mixed material in the recessed groove 36 is compressed into the recessed groove 36 by the pressing force from the molded part 54. The shape that fills the space, that is, the flange-shaped portion 55 that has entered the engagement groove 37 on the circumferential side of the recessed groove 36, and each recessed hole 40 in the bottom surface 38 of the recessed groove 36 through the through hole 41 of the yoke member 33. The protrusion 56 that has entered the inside
. . 56 is molded as a magnet molded body 57.

Furthermore, the end face of the magnet molded body 57 on the opening side of the recessed groove 36, that is, the magnetic pole face 58, has a shape that follows the lower end face of the molded part 54 of the upper die 53. As shown in FIGS. 9 and 10, the end surface has a shape in which concave curved surfaces recessed upward in the axial direction are arranged every 90 degrees in the circumferential direction. More specifically, the upper vertex of the highest end of one concave curved surface is defined as point a, the lower vertex at a position 45 degrees in the circumferential direction from this point a is defined as point b, and from this point b to the above point a When the axial dimension of is T, each of the concave curved surfaces is formed such that the axial dimension from the above point at a position θ degrees away from the above point a in the circumferential direction is L=Tcos2θ. There is. Therefore, the magnetic pole face 58 of the magnet molded body 57 is formed into an uneven shape in the axial direction along the end face shape of the molded part 54 of the upper die 53 as described above.

As shown in FIG. 1, a shaft portion 59 for concentric positioning that extends upward is provided at the axial center position of the lower mold 51, and this shaft portion 59 is connected to the shaft center hole 34 of the casing 31 and the upper mold. 53
The lower mold 51, the casing 31, and the upper mold 5 during the compression molding are inserted into the axial center through hole 60 of the
The concentric state with 3 is maintained.

After performing the above compression molding, the casing 31 is molded from the lower mold 51.
Take out the. Note that the extraction jig 61 used at this time
are shown in FIGS. 11 and 12, and the four knockout pins 62 . A through hole 63 that penetrates from the bottom surface to the lower end surface
...63 from below, and then remove the above-mentioned extraction jig 6.
1, the casing 31 is moved into the recess 5.
This casing 31 is removed by pushing it up to the upper end position of 2.

Thereafter, the casing 31 is placed in a constant temperature bath and heated to the hardening temperature of the binder to harden the binder. Then, the casing 31 is applied to a magnetizing machine, and the magnet molded body 57 is magnetized so that four magnetic poles in the circumferential direction N, S, N, and S are generated on the magnetic pole surface 5th, and the permanent magnet 32 is formed. Configure. In this case, the magnetic pole surface 5 is formed as an uneven surface in the axial direction; The center of each magnetic pole is located at the apex position, and the boundary between adjacent different poles is located at each recessed apex position in the axial direction formed along each lower apex portion of the molded portion 54, The magnetizing yoke of the magnetizer and the circumferential position of the magnet molded body 57 are aligned and magnetized.

As the magnetic powder material, rare earth magnetic powder consisting of neodymium, iron, and boron is used. These rare earth permanent magnets have an energy product that is 3.6 times larger than the conventionally widely used ferrite magnets, and therefore can be configured with a shape that is about 1/3 the size of conventional permanent magnets. It is possible. Regarding the mixing amount of the binder, if the amount is too small and the surface of the magnet molded body 570 is not sufficiently covered, problems such as surface peeling and rust will occur, whereas if the mixing amount is too large, problems such as surface peeling and rust will occur. In this case, the energy product per unit volume becomes smaller and the surface layer becomes thicker, which causes a reduction in rotational force similar to an increase in the air gap between the stator and the stator. sets the mixing ratio to the magnetic powder at about 2% by weight, thereby suppressing the occurrence of the above-mentioned problems and maximizing the energy product per unit volume.

The rotor 3 manufactured as described above is attached to the side plate 2 of the fan rotor 1 as shown in FIG. In this case, the rotor 3 is assembled by inserting the rotary support shaft 71 erected at the axial position of the side plate 2 into the axial hole 34 of the casing 31 of the rotor 3. After fitting the spacer 72 onto the rotating shaft 71, the tip of the rotating shaft 71 is inserted into the bearing 18 housed in the bearing case 19, thereby fixing the rotor 3. An assembly is performed to rotatably support the fan rotor 1. At this time, the spacer 72 located between the left end face of the inner ring of the bearing and the casing 31 of the rotor 3 allows the magnetic pole faces 58 of the permanent magnets 32 of the rotor 3 to face each other in the axial direction. The assembled state is such that the distance between the stator magnetic pole portion 9 and the tip end face is maintained at a predetermined dimension.

In the fan device having the above configuration, a drive signal is generated by the control IC at a predetermined timing upon receiving a detection signal of the rotational position of the rotor 3 by the Hall element 21, and this causes the IL power to be applied to each coil 6. is periodically controlled to generate a rotating magnetic field on the stator 4 side. The rotor 3 and fan rotor 1 are rotationally driven by this rotating magnetic field.

In such a rotational drive state, in the above device, the air gap between the magnetic pole surface 58 of the permanent magnet 32 and the stator magnetic pole portion 9 is larger in the boundary region of adjacent different poles than in the center region of each magnetic pole. As shown, the magnetic pole face 58 is formed in an uneven shape.

This results in an operation with reduced cogging and therefore less vibration. and a permanent magnet 32 as described above.
The shape of the magnetic pole surface 58 can be made without polishing and finishing.
Since it is formed during compression molding of the mixed material within the recessed groove 36 of the casing 31, an electric motor with improved characteristics can be manufactured at a lower cost.

Further, in the rotor 3, as described above, the magnet molded body 57 is connected to the flange portion 55 fitted into the engagement groove 37 of the casing 31, the through hole 4I of the yoke member 33, and the recessed hole 40 of the casing 31. The recessed groove 36 of the permanent magnet 32 is
casing 31, yoke member 3
3. A structure is provided to prevent idling between the permanent magnets 32, and there is no need for separate parts to prevent removal or idling, and no additional processing is required, which also makes manufacturing cheaper. It has become possible.

The specific embodiments of the present invention have been described above, taking as an example the configuration of a DC brushless morph type electric motor that drives a cross-flow fan. Furthermore, it is possible to apply the present invention to a generator as well.

(Effects of the Invention) As described above, in the method for manufacturing a rotating power machine according to the first claim of the present invention, magnetic powder mixed with a binder is compression-molded in the recessed groove of the casing of the rotor or stator. By doing so, a permanent magnet is formed that follows the shape of the recessed groove, and the structure is assembled as is, and there is no need for polishing and finishing the permanent magnet, so manufacturing costs can be lowered. .

Further, in the method for manufacturing a rotating electric power machine according to the second aspect, the uneven magnetic pole surface shape of the permanent magnet, which can reduce cogging in an electric motor, for example, can be formed into the concave groove of the casing without performing polishing finishing. Since it is formed during compression molding of a mixed material, a rotary power machine with improved characteristics can be manufactured at a lower cost.

Further, in the method for manufacturing a rotating electric power machine according to the third aspect, a structure for preventing the permanent magnet from coming out of the recessed groove further includes a fourth aspect.
In the method for manufacturing a rotating power machine according to the claims, the idling prevention structure between the casing, the yoke member, and the permanent magnet is formed during compression molding of the mixed material in the recessed groove of the casing, and prevents slippage. Since there is no need for parts or additional processing to prevent idle running, the structure becomes less expensive and the number of manufacturing steps can be reduced, which also reduces manufacturing costs. can.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a compression molding die for explaining the compression molding process when forming a rotor of a fan drive motor by applying the manufacturing method of a rotating electric power machine of the present invention, and FIG. FIG. 3 is a front view of the iron core in the stator of the fan driving motor, and FIG. 4 is IV-rV of FIG. 3.
5 is a sectional view of the casing of the rotor, FIG. 6 is a sectional view of the yoke member of the rotor, FIG. 6 is a sectional view of the yoke member of the rotor, and FIG. Figure 8 is the ■− of Figure 7.
■ Figure 9 is a front view of the upper mold of the compression molding mold, Figure 10 is a view taken along the line X-X in Figure 9, and Figure 11 is a view for removal used after the compression molding process. Cross-sectional view of jig, 12th
The figure is a view taken along the line xri-xn in FIG. 11. 3... Rotor, 4... Stator, 31... Casing, 32... Permanent magnet, 33... Yoke member, 36
... Recessed groove, 37... Engagement groove (engaging part), 38...
・Bottom surface, 40...Four holes, 41...Through hole (penetrating part), 56...Protrusion, 57...Magnet molded body, 58...
...Magnetic pole surface. Figure 5 Figure 7 Figure 6 h$8 Figure 9 Figure 3 / Figure 10

Claims (1)

[Claims] 1. The magnetic pole portions of the rotor (3) and stator (4) are made to face each other in the axial direction, and the rotor (3) and stator (4)
A method for manufacturing a rotating electric machine in which the magnetic pole part of one (3) of said permanent magnet (32) is composed of a permanent magnet (32).
2) is made of a non-magnetic material, and an annular recessed groove (36) is formed in the end face of this casing (31), and the bottom surface inside this recessed groove (36) is made of a non-magnetic material. The yoke member (33) made of soft magnetic material is located on the (38) side.
), a mixed material of magnetic powder and a binder made of thermosetting resin or the like is injected into the recessed groove (36),
Next, the mixed material is compression molded to form a magnet molded body (57).
After forming, the binder is hardened, and then a plurality of different magnetic poles are arranged alternately in the circumferential direction on the magnetic pole surface (58) on the open end side of the recessed groove (36) in the magnet molded body (57). A method for manufacturing a rotating power machine, characterized in that the magnet molded body (57) is magnetized as much as possible. 2. The magnetic pole face (58) has a shape in which the boundary region of different poles adjacent to each other in the circumferential direction is recessed closer to the bottom surface (38) of the recessed groove (36) than the central region of the magnetic pole. 2. The method of manufacturing a rotating power machine according to claim 1, wherein the magnet molded body (57) is formed by compression molding the mixed material. 3. An engaging portion (37) having a surface that intersects with the withdrawal direction is provided on the circumferential side of the recessed groove (36) in order to prevent the magnet molded body (57) from being withdrawn toward the open end side. , manufacturing a rotary power machine according to claim 1 or 2, characterized in that a molded magnet (57) having a circumferential side along the engaging portion (37) is formed by compression molding the mixed material. Method. 4. The yoke member (33) is provided with a through portion (41) that penetrates from the open end side of the recessed groove (36) to the bottom side, and the A recessed hole (40) is formed at the location where the penetration part (41) is located, and the penetration part (40) is formed by compression molding into the mixed material.
A molded magnet (57) having a projection (56) inserted into the casing (31) and the recessed hole (40) is formed by compression molding the mixed material. 33) and the molded magnet body (57), the method for manufacturing a rotating power machine according to claim 1, 2 or 3, characterized in that idle rotation between the molded magnet body (57) and the molded magnet body (57) is prevented.