JP4394079B2 - Motor rotor, motor and air conditioner - Google Patents

Description

  The present invention relates to a rotor of an electric motor such as a brushless motor or a stepping motor.

  Conventionally, this small motor rotor has a rotating shaft and a rotary shaft in order to increase the production efficiency in order to achieve sufficient performance from all the small to large in a small motor, and to roughen the dimensional accuracy of each member. In order to integrate the permanent magnet and the rotating shaft with the permanent magnet, it has an intervening resin portion that is interposed between the two and made of resin used during insert molding, and contains a soft magnetic material in the intervening resin portion In this intervening resin portion, a rotor for a small motor is proposed in which the polyamide resin is preferably 8 to 20% by weight and the soft magnetic material is 80 to 92% by weight (see, for example, Patent Document 1).

  In addition, to provide an inexpensive rotor structure for a rotating electrical machine that is simple in structure, and the rotor, coupling portion, and cylindrical magnet are firmly coupled, and the ring-shaped thin magnet is not damaged during assembly. In a rotor structure of a rotating electrical machine in which a cylindrical magnet is fixed to a rotating shaft, a cylindrical magnet in which grooves inclined inward from the outer peripheral direction to the inner peripheral direction and a stepped portion subsequent thereto are formed on both side surfaces. A rim portion bent inward is formed in the central portion, a side plate disposed on the side surface of the cylindrical magnet, a position inside the cylindrical magnet, a separate rotary shaft portion, and a cylinder And a coupling portion for coupling the mold magnet and the rotating shaft portion and for applying a force for pressing the step portion of the cylindrical magnet in the direction of the rotating shaft and a force for pressing the side plate against the side portion of the cylindrical magnet. Resin mold Rotor structure having a concrete has been proposed (e.g., see Patent Document 2).

  In addition, it is possible to assemble the shaft and the outer diameter of the resin magnet of the rotor with high precision, and to obtain a rotor for the motor that can improve productivity and quality. In the rotor of an electric motor in which a detection magnet and a shaft are integrally molded with a resin, a plurality of notches for positioning during resin molding are provided on the inner diameter of one end surface of the ring-shaped rotor magnet. An electric motor rotor has been proposed (see, for example, Patent Document 3).

In addition, in order to obtain a plastic magnet rotor that can reduce transmission vibration force and reduce noise at a low price, a magnetic pole portion formed of a polar-oriented plastic magnet, a shaft arranged on the central axis, a shaft And a connecting part formed of a thermoplastic resin softer than a plastic magnet, with axial ribs arranged radially in the radial direction with a hollow formed in the axial direction between the ribs. There has been proposed a plastic magnet rotor in which a portion is coupled to a shaft via a connecting part (see, for example, Patent Document 4).
Japanese Patent Application Laid-Open No. 10-257701 (5th page, FIG. 1) Japanese Patent Laid-Open No. 7-31120 (pages 2 and 3, FIG. 1) Japanese Patent Laying-Open No. 2005-102390 (page 8, FIG. 1) JP 2001-320844 A (page 3, FIG. 1)

  In a conventional rotor in which a magnetic path is formed using a back yoke, a permanent magnet and a shaft are inserted, and a back yoke is formed by molding integrally with a thermoplastic resin containing a soft magnetic material. The shaft was integrated. A thermoplastic resin containing a soft magnetic material is an expensive resin, and a thermoplastic resin containing a soft magnetic material is used for both a back yoke portion functioning as a back yoke and an intervening resin portion integrating a permanent magnet and a shaft. If used, the weight of the resin used increases and the price increases.

  When a back yoke formed of a thermoplastic resin containing a permanent magnet, shaft, and soft magnetic material is molded integrally with a general-purpose thermoplastic resin, the cost is low, but there is a gap between the back yoke due to the shrinkage of the thermoplastic resin. Occurs and causes noise. Therefore, as in Patent Document 2, on both side surfaces of the back yoke formed of a resin containing a soft magnetic material, a groove inclined inward from the outer peripheral direction toward the inner peripheral direction and a stepped portion subsequent thereto are formed. It is possible to generate a pressing force to the shaft side by shrinkage after integral molding with the shaft so that there is no gap, but a groove inclined inwardly from the outer peripheral direction to the inner peripheral direction and the following step Since the portion is formed in the back yoke, the back yoke becomes large and expensive.

  The present invention has been made to solve the above-described problems, and aims to reduce the price, noise, productivity, and quality of a rotor of an electric motor.

  The rotor of the electric motor according to the present invention includes a rotor magnet having a shaft, a back yoke formed of a thermoplastic resin containing soft magnetic material or ferrite, and a plastic magnet disposed on the outer periphery of the back yoke, and a position detection In a rotor of an electric motor in which a magnet for molding is integrally formed of a thermoplastic resin, the back yoke has a plurality of recesses on one axial end face, and a pedestal for positioning the position detecting magnet on the other axial end face The shaft, the rotor magnet, and the position detection magnet are integrally formed of a thermoplastic resin so as to embed the recess and the base of the back yoke.

  The rotor of the electric motor according to the present invention can minimize the amount of the thermoplastic resin containing the soft magnetic material due to the above configuration, and is inexpensive. Also, since the shaft, the rotor magnet, and the position detection magnet are formed integrally with the shaft, the rotor magnet, and the position detection magnet so as to embed the recess and the pedestal, the thermoplastic resin is formed in the step of the gate recess when the thermoplastic resin is molded. Since the gap is not generated due to the hooking, the noise is reduced.

Embodiment 1 FIG.
1 to 9 are diagrams showing the first embodiment. FIG. 1 is a sectional view of the rotor 100 of the electric motor (AA sectional view of FIG. 2), and FIG. 3 is a side view of the position detecting magnet 11 side of FIG. 1, FIG. 4 is a view showing the rotor magnet 3 ((a) is a side view of the recess 6 side, and (b) is a side view of (a). FIG. 5 is a perspective view of the rotor magnet 3 as viewed from the recessed portion 6 side, and FIG. 6 is a perspective view of the rotor magnet 3 as viewed from the base 8 side. FIGS. 7 and 7 are diagrams showing the position detecting magnet 11 ((a) is a plan view, (b) is a cross-sectional view taken along the line CC in FIG. 8), and FIG. 8 is a partially enlarged view of the position detecting magnet 11. 9 is a view showing a manufacturing process of the rotor 100 of the electric motor.

  In the rotor 100 of the electric motor shown in FIG. 1, the shaft 1, the rotor magnet 3, and the position detection magnet 11 are set in a resin molding die, and a thermoplastic resin 17 such as PBT (polybutylene terephthalate) is placed. It is molded by being injected into a resin mold.

  A knurled portion 2 is applied to a portion of the shaft 1 that contacts the thermoplastic resin 17. Knurl means a jagged shape in French, and it is called knurling in English. It is generally called knurling at a manufacturing site in Japan, and is mainly applied to the outer periphery of a round object (here, shaft 1), and has a role as a slipper. For example, in an invisible part, the friction coefficient is mainly increased at the connection part of the press-fitting part (insert), or the jaggedness is eaten into the inner diameter, and the stopper is used as a detent.

  The rotor magnet 3 is obtained by forming a plastic magnet 5 on the outer periphery of a back yoke 4 formed of a thermoplastic resin containing a soft magnetic material by resin molding.

  As will be described in detail later, the back yoke 4 has a ring shape, the outer periphery has a corrugated shape, and the inner periphery has a tapered shape that widens with respect to both end faces to improve moldability. The back yoke 4 has a recess 6 on one end face in the axial direction. A gate for resin molding of the back yoke 4 is located in the recess 6 so that the gate mark is hidden in the recess 6.

  Further, the back yoke 4 has a tapered notch 7 on the inner periphery of one end face in the axial direction. At the time of resin molding of the plastic magnet 5 of the rotor magnet 3, the taper-shaped notch 7 is pressed and molded by a mold so that the uneven thickness of the plastic magnet 5 can be reduced.

  The back yoke 4 is provided with a plurality of pedestals 8 in the circumferential direction on the other end face in the axial direction. The axial end surface of the pedestal 8 serves as an installation surface for the position detection magnet 11, and the position detection magnet 11 is positioned in the axial direction.

  The protrusion 9 formed on the outer peripheral portion of the axial end of the base 8 has a distance between the opposing protrusions 9 substantially equal to the outer diameter of the ring-shaped position detection magnet 11. Positioning in the radial direction.

  The rib 10 protruding in the radial direction from the base 8 is provided to set the back yoke 4 in the mold by aligning the rib 10 with the groove of the mold when the plastic magnet 5 is molded.

  Both end surfaces of the portion of the thermoplastic resin 17 that is fitted to the shaft 1 are surfaces 19 that hold the bearing.

  The shaft 1, the rotor magnet 3, and the position detection magnet 11 are set in a mold, and a thermoplastic resin 17 is injected into the mold from the gate 15 shown in FIG. The gate 15 is disposed on the convex portion 16 further inside than the inner diameter of the back yoke 4, thereby reducing the concentration of pressure, facilitating resin filling, and improving moldability. Further, it is possible to use the convex portion 16 for position detection and positioning by magnetizing a magnet in a later process.

  As shown in FIGS. 2 and 3, the shaft 1 and the rotor magnet 3 are connected and integrated by ribs 18 arranged radially in the radial direction.

  The rotor magnet 3 will be further described with reference to FIGS. As already described, the rotor magnet 3 has a configuration in which the plastic magnet 5 is formed on the outer periphery of the back yoke 4 formed of a thermoplastic resin containing a soft magnetic material.

  The shape of the back yoke 4 formed of a thermoplastic resin containing a soft magnetic material is a ring shape, the outer periphery is a corrugated shape, and the inner periphery is a tapered shape that expands with respect to both end faces to improve moldability (see FIG. 4 (b)). Therefore, it is easy to set the back yoke 4 in the mold.

  On one end face in the axial direction of the back yoke 4, a plurality of recesses 6 are provided so that the gate trace after molding does not protrude from the end face. Further, on the inner diameter side of the back yoke 4, notches 7 tapered from the end face are provided at equal intervals between the recesses 6 (see FIGS. 4A and 5).

  Further, on the other axial end surface of the back yoke 4, a plurality of pedestals 8 and ribs 10 including protrusions 9 protruding radially from the outer peripheral side of the pedestal 8 are provided in the circumferential direction at equal intervals ( FIG. 4 (c) and FIG. 6). The pedestal 8 serves as an installation surface for the position detection magnet 11, and the position detection magnet 11 is positioned in the axial direction at a predetermined distance from the end face of the back yoke 4. Further, the outer diameter of the position detecting magnet 11 is fitted between the opposing protrusions 9 of the base 8 of the back yoke 4, and the inner diameter pressing portion 14 (see FIG. 1) of the position detecting magnet is held in the mold. Thus, positioning is performed in the radial direction, and coaxiality with the shaft 1 and the rotor magnet 3 is ensured. Without using other parts such as spacers, positioning is not performed over the entire end face of the back yoke 4, and the volume of the thermoplastic resin containing the soft magnetic material, which is expensive, is reduced by setting the base 8 to the minimum necessary volume. Minimize the cost. The protrusion 9 may be provided on the inner peripheral side of the base 8 so that the inner diameter of the position detecting magnet 11 is fitted between the opposing protrusions 9.

  Next, the position detection magnet 11 will be described with reference to FIGS. As shown in FIGS. 7 and 8, the ring-shaped position detecting magnet 11 includes steps 12 at both axial ends on the inner diameter side, and is symmetrical in the thickness direction. The position detection magnet 11 is provided at one end in the axial direction of the rotor 100 of the electric motor (see FIG. 1), but a thermoplastic resin such as PBT is formed on the step 12 at both ends in the axial direction on the inner diameter side of the position detection magnet 11. 17 is filled to prevent the position detecting magnet 11 from coming off in the axial direction. Since the position detecting magnet 11 has a symmetrical shape in the thickness direction, it can be set in the mold without considering the direction, the working time can be shortened, productivity can be improved, and cost can be reduced.

  7 and 8 show a step 12 at both ends, but there is a step 12 at one end, which is located on the axial end of the rotor 100 of the motor. That's fine.

  Further, the position detection magnet 11 includes a rib 13 that prevents rotation when embedded in the thermoplastic resin 17.

  Next, a manufacturing process of the rotor 100 of the electric motor will be described with reference to FIG. Here, the thing before attaching a bearing is made into the rotor 100 of an electric motor.

  First, the back yoke 4 is molded with a thermoplastic resin containing a soft magnetic material (S10).

  The back yoke 4 is set in the mold by aligning the rib 10 of the base 8 of the back yoke 4 with the groove of the mold corresponding to the rib 10 (S20).

  The tapered notch 7 provided on the inner peripheral portion of the back yoke 4 is pressed with a mold to mold the plastic magnet 5, thereby completing the rotor magnet 3 (S30).

  The plastic magnet 5 is demagnetized (S40).

  The shaft 1 is processed in a separate process from the rotor magnet 3 (S50).

  Similarly, the position detecting magnet 11 is formed in a separate process from the rotor magnet 3 (S60).

  The position detecting magnet 11 is demagnetized (S70).

  The shaft 1, the rotor magnet 3, and the position detection magnet 11 are set in the mold (S80).

  A thermoplastic resin 17 such as PBT is injected into the mold, and the rotor 100 of the electric motor is integrally formed (S90).

  The plastic magnet 5 and the position detection magnet 11 are magnetized (S100).

  A bearing (described later) is assembled to the rotor 100 of the electric motor (S110).

  In S30, the back yoke 4 is set in accordance with the groove of the mold corresponding to the rib 10 of the base 8 of the back yoke 4 molded with a thermoplastic resin containing a soft magnetic material in the mold for molding the plastic magnet 5. By pressing the taper-shaped notch 7 with a mold and forming the plastic magnet 5, the plastic magnet 5 is disposed on the outer periphery of the back yoke 4 and becomes the rotor magnet 3. The taper-shaped notch 7 having an inner diameter of the back yoke 4 is pressed by a mold, so that the uneven thickness of the plastic magnet 5 can be reduced, noise can be reduced, and quality can be improved. Further, since the ribs 10 are arranged at equal intervals, the setting work is facilitated and the cost can be reduced. At this time, the inner periphery of the plastic magnet 5 is prevented from rotating because the waveform of the outer periphery of the back yoke 4 is transferred and meshes with each other. Further, since the magnetic path is formed by making the outer periphery of the back yoke 4 into a wave shape, the magnetic flux density distribution can be arbitrarily adjusted.

  In S80, the outer diameter of the position detecting magnet 11 is fitted between the opposing protrusions 9 of the base 8 of the back yoke 4, and the inner diameter pressing portion 14 (see FIG. 1) of the position detecting magnet is held in the mold. In this way, positioning is performed in the radial direction, and coaxiality with the shaft 1 and the rotor magnet 3 is ensured. Without using other parts such as spacers, positioning is not performed over the entire end face of the back yoke 4, and the volume of the thermoplastic resin containing the soft magnetic material, which is expensive, is reduced by setting the base 8 to the minimum necessary volume. Minimize the cost. Furthermore, since the position detecting magnet 11 has a symmetrical shape in the thickness direction, it can be set without considering the direction, work time can be shortened, productivity can be improved, and cost can be reduced.

  In S90, both end surfaces of the rotor magnet 3 are filled with the thermoplastic resin 17 up to the vicinity of the outer periphery of the plastic magnet 5 disposed on the outer periphery thereof, and are sandwiched by the thermoplastic resin 17 to prevent axial removal. By pressing both ends near the outer periphery of the plastic magnet 5 with a mold and filling the thermoplastic resin 17, burrs are prevented from occurring on the outer periphery of the plastic magnet, and the deburring operation is not generated, thereby improving productivity and quality. I can plan.

  In addition, a thermoplastic resin 17 is filled so that a part of the notch 7 of the back yoke 4, the recessed portion 6 of the gate, and the pedestal 8 are buried, thereby preventing torque transmission and rotation in the rotation direction. By completely filling the recessed portion 6 and the pedestal 8 of the gate, even if the thermoplastic resin 17 contracts to the inner diameter side, the thermoplastic resin 17 is caught by the outer peripheral surface of the recessed portion 6 and the pedestal 8 of the gate, thereby preventing a decrease in bonding force. It is possible. In other words, by using the recess 6 for eliminating the protrusion of the gate processing trace and the pedestal 8 for positioning the position detection magnet 11, it is not necessary to add a structure for preventing a decrease in the coupling force, thereby reducing the price. And low noise.

  The position detecting magnet 11 is filled with resin in the step 12 on the inner peripheral side, and is prevented from coming off by the step 12 and is prevented from rotating by the rib 13. Further, since the end surface on one side is pressed by the mold, it is possible to prevent the position detecting magnet 11 from being lifted during molding and to prevent burrs from occurring on the end surface, thereby improving productivity and quality.

  In this embodiment, as shown in FIG. 4, the rotor magnet 3 in which the outer periphery of the back yoke 4 has a wave shape and the plastic magnet 5 is integrally formed on the outer periphery is used. Alternatively, the rotor magnet 3 may be formed by forming a plastic magnet 5 on the outer periphery of the back yoke 4 having a concave shape or a convex shape.

  Alternatively, a sintered magnet or a molded plastic magnet 5 may be bonded to the back yoke 4 to form the rotor magnet 3.

  Regardless of the outer peripheral shape of the back yoke 4, the material of the magnet disposed on the outer periphery, and the fixing method, the gate processing trace provided on one end surface of the back yoke 4 formed of a thermoplastic resin containing a soft magnetic material is seen from the end surface. It is possible to obtain the same effect by molding with a general-purpose thermoplastic resin 17 so as to bury the concave portion 6 so as not to protrude and integrating the shaft 1, the rotor magnet 3 and the position detection magnet 11. Needless to say.

  In addition, it has been shown that the positioning of the rotor magnet 3 when integrally molded with the general-purpose thermoplastic resin 17 is the notch 7 in the inner diameter of the back yoke 4, but when the positioning cannot be installed on the inner diameter due to the mold structure, The rib 10 provided on the outer periphery of the pedestal 8 on the end face of the back yoke 4 may be extended until it protrudes from the surface of the thermoplastic resin 17 for positioning.

Further, a rib 10 may be provided on the end face of the plastic magnet 5 disposed on the outer periphery of the back yoke 4 for positioning.
When the plastic magnet 5 is a rare earth, the back yoke 4 may be formed of a thermoplastic resin containing low grade ferrite.

Embodiment 2. FIG.
FIGS. 10 to 13 are diagrams showing the second embodiment. FIG. 10 is a sectional view of the rotor 200 of the motor (DD sectional view of FIG. 11). FIG. 12 is a side view of the position detecting magnet 11 side of FIG. 10, FIG. 13 is a view showing the rotor magnet 3 ((a) is a side view of the recess 6 side, and (b) is a side view of (a). EE sectional drawing, (c) is a side view by the side of the base 8).

  In FIG. 10, the rotor magnet 3 is formed by polar orientation of a plastic magnet. Others are the same as those in the first embodiment, and a description thereof will be omitted.

  As shown in FIGS. 10 to 12, a shaft 1, a rotor magnet 3 formed by polar orientation of plastic magnets, and a position detection magnet 11 are molded and integrated with a thermoplastic resin 17 such as PBT.

  The rotor magnet 3 has a ring shape as shown in FIG. 13, and both end surfaces of the inner periphery are tapered. A plurality of recesses 6 are provided in the circumferential direction on one axial end face, and the center of the recess 6 is a gate for injecting a plastic magnet. The recessed part 6 is for preventing the gate processing trace after shaping | molding from protruding from an end surface.

  A plurality of notches 7 tapered from one axial end face are provided on the inner diameter side of the rotor magnet 3.

  A plurality of pedestals 8 are provided on the other axial end face. On the outer peripheral side of the pedestal 8, a rib 10 having a protrusion 9 on the end surface is provided. The base 8 is used to position the position detection magnet 11 in the axial direction. The distance between the opposing protrusions 9 is equal to the outer diameter of the position detection magnet 11 so that the protrusions 9 are positioned in the radial direction.

  In the first embodiment, the rotor magnet 3 that forms a magnetic path using the back yoke 4 formed of a thermoplastic resin containing a soft magnetic material is used. However, the rotor magnet 3 of the present embodiment is a soft magnetic material. The magnetic yoke is formed by polar-orienting the plastic magnet without using the back yoke 4 formed of the thermoplastic resin containing the magnetic material, and the overall shape is the rotor magnet 3 of the first embodiment. Is the same.

  The rotor magnet 3 formed by polar orientation of the above plastic magnets, the shaft 1 and the position detection magnet 11 similar to those of the first embodiment are integrally molded with the thermoplastic resin 17, so that the first embodiment is formed. Similarly to the above, the rotor 200 of the electric motor with low noise and improved productivity and quality can be obtained without causing a decrease in the bonding force between the rotor magnet 3 and the thermoplastic resin 17.

Embodiment 3 FIG.
FIG. 14 is a diagram illustrating the third embodiment, and is a diagram illustrating the electric motor 1000 ((a) is a side view, and (b) is an FF cross-sectional view of (a)).

  As shown in FIG. 14, the electric motor 1000 includes the stator 20, the electric motor rotor 100 according to the first embodiment, or the electric motor rotor 200 according to the second embodiment, a bearing 22, and a bracket 23.

  In FIG. 14, the rotation of the rotor 100 of the electric motor of the first embodiment or the electric motor of the second embodiment in which the bearing 22 is press-fitted and fixed until it contacts the surface 19 of the thermoplastic resin 17 formed by integrally molding the shaft 1. The child 200 is inserted into the hollow portion inside the stator 20, and the bracket 23 is press-fitted into the stator 20 so that the bearing 22 is held by the surface stator 20 and the bracket 23, thereby obtaining the electric motor 1000.

  By using the electric motor rotor 100 according to the first embodiment or the electric motor rotor 200 according to the second embodiment, the motor 1000 can be reduced in price, noise, and productivity and quality can be improved.

Embodiment 4 FIG.
FIG. 15 is a diagram showing the fourth embodiment and is a configuration diagram of the air conditioner 30.

  The air conditioner 30 includes an indoor unit 24 and an outdoor unit 25. The indoor unit 24 is connected to the outdoor unit 25. The indoor unit 24 and the outdoor unit 25 include a blower 26 that is driven by the electric motor 1000 of the third embodiment. The blower 26 of the indoor unit 24 is not shown.

  In recent years, the air conditioner 30 has been reduced in price and noise, and it is preferable to use the electric motor 1000 of Embodiment 3 as the electric motor of the blower 26 that is a main part of the air conditioner 30.

  Thereby, the blower 26 of the air conditioner 30 is reduced in price, reduced in noise, and improved in productivity and quality.

It is a figure which shows Embodiment 1, and is sectional drawing (AA sectional drawing of FIG. 2) of the rotor 100 of an electric motor. FIG. 3 is a diagram showing the first embodiment, and is a side view on the opposite position detection magnet 11 side of FIG. 1. FIG. 3 is a diagram showing the first embodiment and is a side view on the position detection magnet 11 side of FIG. 1. FIG. 2 is a diagram illustrating the first embodiment, and is a diagram illustrating the rotor magnet 3 ((a) is a side view on the concave portion 6 side, (b) is a cross-sectional view along BB of (a), and (c) is a diagram on the pedestal 8 side. Side view). FIG. 5 shows the first embodiment, and is a perspective view of the rotor magnet 3 as viewed from the concave portion 6 side. FIG. 5 shows the first embodiment, and is a perspective view of the rotor magnet 3 as viewed from the pedestal 8 side. FIG. 5 is a diagram illustrating the first embodiment, and is a diagram illustrating a position detection magnet 11 ((a) is a plan view, and (b) is a cross-sectional view taken along the line CC in (a)). FIG. 5 shows the first embodiment and is a partially enlarged view of a position detection magnet 11. It is a figure which shows Embodiment 1 and is a figure which shows the manufacturing process of the rotor 100 of an electric motor. It is a figure which shows Embodiment 2, and is sectional drawing (DD sectional drawing of FIG. 11) of the rotor 200 of an electric motor. It is a figure which shows Embodiment 2, and is a side view by the side of the opposite position detection magnet 11 of FIG. It is a figure which shows Embodiment 2, and is a side view by the side of the position detection magnet 11 of FIG. FIG. 6 is a diagram illustrating the second embodiment, and is a diagram illustrating the rotor magnet 3 ((a) is a side view on the concave portion 6 side, (b) is a cross-sectional view taken along line EE of (a), and (c) is a diagram on the base 8 side). Side view). It is a figure which shows Embodiment 3, The figure ((a) is a side view, (b) is FF sectional drawing of (a)) which shows the electric motor 1000. It is a figure which shows Embodiment 4, and is a block diagram of the air conditioner 30. FIG.

Explanation of symbols

  1 axis, 2 knurls, 3 rotor magnets, 4 back yoke, 5 plastic magnets, 6 recesses, 7 notches, 8 bases, 9 protrusions, 10 ribs, 11 position detection magnets, 12 steps, 13 ribs, 14 position detection Inner diameter pressing part, 15 gate, 16 convex part, 17 thermoplastic resin, 18 rib, 19 bearing stop surface, 20 stator, 22 bearing, 23 bracket, 24 indoor unit, 25 outdoor unit, 26 blower , 30 air conditioner, 100 electric motor rotor, 200 electric motor rotor, 1000 electric motor.

Claims (11)

A rotor magnet having a shaft, a back yoke formed of a thermoplastic resin containing soft magnetic material or ferrite, a plastic magnet disposed on the outer periphery of the back yoke, and a position detection magnet are integrated with the thermoplastic resin. In the rotor of the electric motor to be molded into
The back yoke has a plurality of recesses on one axial end face, and a pedestal for positioning the position detecting magnet on the other axial end face,
The shaft, the rotor magnet, and the position detection magnet are integrally formed of a thermoplastic resin so as to embed the recess and the pedestal of the back yoke ,
A motor rotor characterized in that a gate at the time of resin molding of the back yoke is located in the recess, and the gate mark remains in the recess . A rotor magnet having a shaft, a back yoke formed of a thermoplastic resin containing soft magnetic material or ferrite, a plastic magnet disposed on the outer periphery of the back yoke, and a position detection magnet are integrated with the thermoplastic resin. In the rotor of the electric motor to be molded into
The back yoke is formed on the outer side of the inner peripheral surface of the back yoke on one axial end surface, has a plurality of recesses with a predetermined depth in the axial direction, and the position detecting magnet on the other axial end surface. It has a pedestal that becomes the positioning of
The motor rotor, wherein the shaft, the rotor magnet, and the position detection magnet are integrally formed of a thermoplastic resin so as to embed the recess and the base of the back yoke. The outer peripheral side axial end surface of the plastic magnet of the rotor magnet is pressed by a mold, and the shaft, the rotor magnet, and the position detection magnet are integrally formed of the thermoplastic resin. The rotor of the electric motor according to claim 1 or 2 . The position detection magnet is in contact with the pedestal of the back yoke, the position detection magnet is arranged at a predetermined distance from the end face of the back yoke, and the thermoplastic resin is filled between the back yoke and the position detection magnet. The rotor of the electric motor according to claim 1 , wherein the rotor is an electric motor. The rotor of the electric motor according to claim 1 or 2 , wherein a protrusion for positioning the position detecting magnet in a radial direction is provided on a base of the back yoke. 2. A radially projecting rib for setting the back yoke to a mold in accordance with a groove of the mold when the plastic magnet is molded is provided on an outer peripheral side of the back yoke base. The rotor of the electric motor according to claim 1 or 2 . 3. The electric motor rotor according to claim 1, wherein a plurality of notches for positioning at the time of molding with the thermoplastic resin are provided in an inner diameter of one axial end face of the back yoke. In a rotor of an electric motor in which a shaft, a rotor magnet formed by polar orientation of a plastic magnet, and a position detection magnet are integrally formed of a thermoplastic resin,
The rotor magnet has a plurality of recesses on one axial end face, and a pedestal that serves as a positioning of the position detection magnet on the other axial end face,
The shaft, the rotor magnet, and the position detection magnet are integrally formed with a thermoplastic resin so as to embed the recess and the pedestal of the rotor magnet ,
A motor rotor characterized in that a gate at the time of molding with the plastic magnet is located in the recess, and the trace of the gate remains in the recess . In a rotor of an electric motor in which a shaft, a rotor magnet formed by polar orientation of a plastic magnet, and a position detection magnet are integrally formed of a thermoplastic resin,
  The rotor magnet is formed on the outer side of the inner peripheral surface of the rotor magnet on one axial end surface, has a plurality of concave portions with a predetermined depth in the axial direction, and detects the position on the other axial end surface. Has a pedestal for positioning the magnet
  The rotation of the electric motor, wherein the shaft, the rotor magnet, and the position detection magnet are integrally formed of a thermoplastic resin so as to embed the recess and the pedestal of the rotor magnet. Child. An electric motor using the rotor of any one of claims 1 to 9 as the rotor. An air conditioner using the electric motor according to claim 10 as a blower.

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