JPH08322173A - Motor rotor - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the number of rotor parts with permanent magnets,
Improve the assemblability. [Structure] An iron core 1 in which an output shaft is fitted in the center, a permanent magnet 2 which is circumferentially divided so as to surround the outer peripheral surface of the iron core 1, and a permanent magnet 2 which is attached to the outer periphery of the permanent magnet 2. The rotor of the motor having the metal cylinder 3 and the two side plates 4 mounted so as to cover both end surfaces of the permanent magnet 2 in the axial direction. The space is kept constant by fitting of radially protruding structure 7 integrally formed on at least one of the side plates 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a motor, and more particularly to a rotor having a permanent magnet used in a brushless motor or the like.

[0002]

2. Description of the Related Art The rotor of a conventional motor of this type is
A permanent magnet divided in the circumferential direction is provided on the outer circumference of an iron core in which the output shaft is fitted in the center, and the outer circumference of this permanent magnet is covered with a metal cylinder. There is something. The former is, for example, JP-A-64
No. 8850, Japanese Patent Application Laid-Open No. 2-174538, and Japanese Patent Application Laid-Open No. 2-36743, the permanent magnets are provided on the outer circumference of the iron core, and a certain gap is formed between the permanent magnets. As described above, the metal cylinder is fitted, and then the gap between the permanent magnets is filled with the Daigast metal. Since this type of rotor is integrally formed by die casting, it has high structural stability and is widely used.

The latter has a structure as shown in JP-A-2-246746 and JP-A-2-246747. For example, as shown in FIGS. 8 and 9, the permanent magnet 101 is provided between the permanent magnets 101. The spacer 102, which keeps the distance between them constant, is attached to the outer periphery of the iron core 103,
The outer periphery of the metal cylinder 104 is covered by fitting the metal cylinder 104.
The side plates 105 are fixed to both ends of 04, respectively. Since this type of rotor does not require die casting equipment, it has an advantage that manufacturing cost can be kept low.

[0004]

In the conventional rotor as described above, it is difficult to bond the permanent magnets to the iron core at equal intervals in the die cast molding, and the permanent magnets are heated by the pressure of the hot water during the die casting. There is a problem that it is difficult to obtain stable motor performance due to the change of the position of. Also, in the case where the permanent magnet 101 is fixed by sandwiching the spacer 102, the spacer 102 is required, and the number of parts is large, and since the spacers 102 must be sandwiched one by one in assembly, it is troublesome and the cost is considerably high. There is a problem such as.

The present invention has been made in order to solve the above-mentioned conventional problems, and its object is to reduce the number of parts of a rotor having a permanent magnet and to improve the assemblability. It is to obtain a rotor of a motor that can improve the positioning accuracy of a permanent magnet in die casting and contribute to stable motor performance.

[0006]

In order to achieve the above object, the invention of claim 1 is provided so as to surround the outer peripheral surface of an iron core in which an output shaft is fitted at the center, and is divided in the circumferential direction. A projecting structure is formed integrally with at least one of the two side plates attached to both ends of the metal cylinder to be covered so as to cover both end faces in the axial direction of the permanent magnet, and the projecting structure of the side plates is integrally formed. The structure is fitted between the permanent magnets, and a means for maintaining a constant gap between the permanent magnets is adopted.

In order to achieve the above-mentioned object, the invention of claim 2 is arranged so as to surround the outer peripheral surface of the iron core in which the output shaft is fitted in the center thereof, and the permanent magnets are divided in the circumferential direction in the axial direction. A projecting structure that is radially aligned inside the two side plates that are attached to both ends of the metal cylinder that is to be installed so as to cover both end faces, is integrally formed by cutting and raising, and the projecting structure of each side plate is formed between the permanent magnets. Means for fitting the gap between the permanent magnets and keeping the distance between the permanent magnets constant, and configuring the open part of the side plate formed by cutting and raising this protruding structure as a runner at the time of die casting for the die casting metal that integrates each member To adopt.

In order to achieve the above-mentioned object, the invention of claim 3 places each projecting structure in the means according to claim 2 in the middle of the open portion, and both of the inside and the outside of the projecting structure are connected in series. The means of constructing as an open part of is adopted.

In order to achieve the above-mentioned object, the invention of claim 4 comprises means for mounting the side plate in the means according to claim 2 by a metal plate having a melting point higher than that of the die-cast metal, and mounting the side plate on both ends of the metal cylinder by press fitting. adopt.

In order to achieve the above object, the invention of claim 5 employs means for chamfering or rounding at least one corner of the circumferential end surface of each permanent magnet of the divided construction in the means according to claim 2. To do.

[0011]

According to the above-mentioned means, the protruding structure formed integrally with the side plate is fitted to the end portion of the metal cylinder of the side plate and is fitted between the permanent magnets so that the permanent magnets are fixed. It is positioned on the outer circumference of the iron core with a space of.

According to the second aspect of the present invention, the protruding structure formed integrally with each side plate is attached to both ends of the metal cylinder of each side plate and is fitted between the permanent magnets so that the permanent magnets are separated from each other. It is positioned on the outer periphery of the iron core with a constant interval. Then, when die-cast molding is performed by using the open portion formed by cutting and raising the protruding structure of the side plate as the runner, the open portion is located in the space between the permanent magnets, so that the die-cast metal is positioned between the positioned permanent magnets. It will be filled smoothly.

According to a third aspect of the present invention, there is provided the second aspect.
With this action, each protruding structure is located in the middle of the open part, and both the inner and outer sides of the protruding structure are a series of open parts. The part will face.

According to a fourth aspect of the present invention, there is provided the second aspect.
The side plate can be formed by drawing together with the action related to, and the side plate is firmly fixed.

According to a fifth aspect of the present invention, there is provided the second aspect.
In addition to the above action, the surrounding of the die-cast metal into the space between the permanent magnets becomes smoother.

[0016]

An embodiment of the present invention will be described below with reference to the drawings. Example 1. FIG. 1 is a longitudinal sectional view showing a rotor of a motor as an embodiment of the present invention, and FIG. 2 is a side view of the same. This rotor has a cylindrical iron core 1 on which an output shaft (not shown) is fitted in the center, and a plurality of circumferentially divided parts (in the example shown in the drawing) which are provided so as to surround the outer peripheral surface of the iron core 1. 4) curved permanent magnets 2 and the permanent magnets 2
A metal cylinder 3 made of a non-magnetic material such as stainless steel and attached to the outer periphery of the permanent magnet 2 and two side plates 4 mounted so as to cover both end surfaces of the permanent magnet 2 in the axial direction.

Each of the permanent magnets 2 has the same shape and size, and as shown in FIG. 3, the outer and inner corners of each circumferential end face 5 are easily chipped, so that chamfering or rounding 6 is applied.
It is fitted between the iron core 1 and the metal tube 3 so as to surround the iron core 1. The permanent magnets 2 are fixed to each other at a constant interval. The spacing between the permanent magnets 2 is maintained by a projecting structure 7 formed integrally with the two side plates 4 press-fitted and fixed in a lid-like shape in the openings at both ends of the metal tube 3.

That is, as shown in an enlarged view in FIGS. 4 and 5, the two side plates 4 are formed into a disk shape by drawing a metal plate, and a rising edge portion 8 for press-fitting is formed on the peripheral edge thereof. A burring shaft insertion hole 9 is formed at the center. Then, four protruding structures 7 are formed by cutting and raising them at equal intervals on the inner surface side that abuts the end surface of the permanent magnet 2 in the mounted state. Each projecting structure 7 is formed in a radial shape so as to have a thickness on the diameter line of the side plate 4.

Each side plate so that each protruding structure 7 is fitted from both sides between the permanent magnets 2 of the respective permanent magnets 2 fitted so as to surround the iron core 1 between the iron core 1 and the metal cylinder 3. The rotors are completed by pressing the four together and press-fitting them into both ends of the metal cylinder 3 to fix them together. As a result, the permanent magnets 2 are held at a constant interval corresponding to the thickness of the protruding structures 7 of the side plate 4, and are constrained both in the circumferential direction and in the radial direction.
If the protruding structure 7 is fixedly attached to the side plate 4 by welding or the like, the protruding amount of the protruding structure 7 can be increased, and the spacing between the permanent magnets 2 can be maintained even with only one protruding structure 7. Since this is possible, it suffices to provide the protruding structure 7 only on one side plate 4.

Example 2. FIG. 6 is a longitudinal sectional view showing a rotor of a motor as an embodiment of the present invention, and FIG. 7 is a side view of the same. This rotor is composed of a cylindrical iron core 1 on which an output shaft is fitted in the center, and a plurality of (four in the example shown in the figure) divided circumferentially so as to surround the outer peripheral surface of the iron core 1. The permanent magnet 2 having a curved shape, the metal cylinder 3 made of a non-magnetic material such as stainless steel, which is attached to the outer circumference of the permanent magnet 2, and the axially opposite end surfaces of the permanent magnet 2 are mounted so as to cover the respective surfaces. Two side plates 4 are provided, and the whole is integrally formed by die casting.

The permanent magnets 2 have the same shape and size as those of the first embodiment, and the outer and inner corners of the respective circumferential end faces 5 thereof are chamfered or rounded as shown in FIG. And is fitted between the iron core 1 and the metal tube 3 so as to surround the iron core 1. The permanent magnets 2 are fixed to each other at a constant interval. The spacing between the permanent magnets 2 is maintained by the protruding structure 7 integrally formed with the two side plates 4 press-fitted and fixed to the openings at both ends of the metal tube 3 in the same manner as in the first embodiment.

That is, the two side plates 4 are formed in a disk shape by drawing a metal plate having a melting point higher than that of die-cast metal such as aluminum as shown in FIGS. , A rising edge portion 8 for press-fitting is formed on the periphery,
A burring shaft insertion hole 9 is formed at the center. Then, four protruding structures 7 are formed by cutting and raising them at equal intervals on the inner surface side that abuts the end surface of the permanent magnet 2 in the mounted state. Each projecting structure 7 is formed in a radial shape so as to have a thickness on the diameter line of the side plate 4. The open portion 10 obtained by cutting and raising these protruding structures 7 is formed as a heart-shaped runner as shown in FIG. That is, each protruding structure 7
Is located in the middle of the open part 10 which is a runner, and both the inside and the outside of the projecting structure 7 enter as the open part 11.

Each side plate so that each protruding structure 7 is fitted from both sides between the permanent magnets 2 of each permanent magnet 2 fitted so as to surround the iron core 1 between the iron core 1 and the metal cylinder 3. 4 are combined and press-fitted to both ends of the metal cylinder 3 respectively, and the die cast metal 12 is filled from the runner of the side plate 4 to complete the rotor by die casting. As a result, the permanent magnets 2 are integrated with each other at regular intervals corresponding to the thickness of the protruding structures 7 of the side plate 4, and are constrained both in the circumferential direction and in the radial direction.

During die casting, the permanent magnets 2 are positioned in a well-balanced manner by the protruding structure 7 of the side plate 4, and are not displaced by the pressure of the hot water. Since each projecting structure 7 is located in the middle of the open part 10 which is a runner, and both the inside and the outside of the projecting structure 7 are open parts 11, the permanent structure is provided in the middle part of the open part 10. Since the space between the magnets 2 faces each other, the die-cast metal 12
A smooth and well-balanced rotor is provided so that the permanent magnets 2 can be smoothly wrapped around the space between them. Particularly, in the second embodiment, since the corners of the end face 5 in the circumferential direction of the permanent magnet 2 are chamfered or rounded, the die cast metal 12 does not go around the space between the permanent magnets 2. It will be smoother. The side plate 4 obtained by drawing the sheet metal is convenient because it is easy to mass produce and does not cost much.

Even if the projecting structure 7 is formed along the rim of the opening 10, it functions sufficiently as a runner, but it is more effective to position the projecting structure 7 in the middle of the runner. If the permanent magnet 2 is chamfered only on the inner peripheral side of the end face 5 in the circumferential direction, the pressure of the hot water at the time of die casting works to press the permanent magnet 2 against the inner surface of the metal cylinder 3 and the rotor having a better balance. And a stable motor with less vibration and noise can be constructed.

[0026]

As is apparent from the description of the embodiment, according to the invention of claim 1, the permanent magnet can be positioned without a spacer, the number of parts can be reduced and the assemblability can be improved, and the cost can be reduced. Reduce.

According to the second aspect of the present invention, the positioning accuracy of the permanent magnets is improved, and the open portions due to the cut-and-raising of the protruding structure of the side plates are located in the gaps between the permanent magnets. The die-cast metal can be smoothly filled in between, and the performance of the motor becomes stable.

According to the invention of claim 3, in addition to the effect according to claim 2, each projecting structure is located in the middle of the open portion, and the space between the permanent magnets faces the middle portion of the open portion. The die-cast metal can be more smoothly filled between the permanent magnets.

According to the invention of claim 4, in addition to the effect of claim 2, mass production of the side plate is easy, and the side plate is firmly fixed.

According to the invention of claim 5, in addition to the effect according to claim 2, the surrounding of the die-cast metal into the space between the permanent magnets becomes smoother.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing the structure of a rotor as an embodiment of the present invention.

FIG. 2 is a side view of the rotor of the embodiment.

FIG. 3 is a perspective view showing the structure of a permanent magnet of the rotor of the embodiment.

FIG. 4 is an enlarged front view of a side plate of the rotor of the embodiment.

5 is a cross-sectional view taken along the line AA in FIG.

FIG. 6 is a vertical sectional view showing the structure of a rotor according to a second embodiment of the present invention.

FIG. 7 is a side view of the rotor according to the second embodiment.

FIG. 8 is a sectional view showing a configuration of a conventional rotor.

FIG. 9 is a side view showing a conventional rotor with a side plate removed.

[Explanation of symbols]

 1 Iron core 2 Permanent magnet 3 Metal cylinder 4 Side plate 6 Chamfering or rounding 7 Projection structure 10 Opening part 11 Opening part 12 Die-cast metal

Claims (5)

[Claims] 1. An iron core having an output shaft fitted in the center thereof, a circumferentially divided permanent magnet provided so as to surround the outer peripheral surface of the iron core, and a permanent magnet attached to the outer circumference of the permanent magnet. A rotor of a motor provided with a metal cylinder and two side plates mounted so as to cover both end surfaces in the axial direction of the permanent magnet, wherein the spacing between the divided permanent magnets is A rotor of a motor, wherein the rotor is held constant by fitting a radially aligned protruding structure integrally formed on at least one of the side plates. 2. An iron core having an output shaft fitted in the center thereof, a circumferentially divided permanent magnet provided so as to surround the outer peripheral surface of the iron core, and a permanent magnet attached to the outer circumference of the permanent magnet. A rotor of a motor provided with a metal cylinder and two side plates mounted so as to cover both end surfaces in the axial direction of the permanent magnet, wherein the spacing between the divided permanent magnets is , Die-cast metal that integrally holds the above-mentioned members by holding the opening portions formed by cutting and raising the protruding structure while holding the same by fitting the protruding structure that is formed by cutting and raising integrally on the inside of each of the side plates A rotor of a motor, which is configured as a runner at the time of die casting. 3. The rotor for a motor according to claim 2, wherein each projecting structure is located in the middle of the open part, and both the inside and the outside of the projecting structure are configured as a series of open parts. A rotor of a motor characterized by the above. 4. The rotor for a motor according to claim 2, wherein the side plate is made of a metal plate having a melting point higher than that of the die-cast metal, and the metal plate is mounted on both ends of the metal cylinder by press fitting. Rotor. 5. The rotor of the motor according to claim 2, wherein at least one corner of the circumferential end surface of each of the split permanent magnets is chamfered or rounded. Rotor.