JP2015091202A - Member for preventing magnet flotation and shatter, and rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a member for preventing magnet flotation and shatter, achieving weight reduction of a rotor, capable of preventing magnet flotation and shatter during high-speed rotation and to provide a rotor.SOLUTION: The cylindrical member for preventing magnet flotation and shatter that prevents flotation and shatter of a magnet 2 includes: a shaft 1; and the magnet 2 formed by coupling in cylindrical shape split bodies provided around the shaft 1, and is provided on an outside of the magnet 2 of a rotor that rotates at a speed of equal to or more than 5000 rpm. A member 3 of preventing magnet flotation and shatter is made of a carbon fiber reinforced resin formed by winding and laminating carbon fibers along an external circumferential direction of the magnet 2. A volume content of the carbon fiber is equal to or more than 75 vol%.

Description

  The present invention relates to, for example, a magnet floating and scattering preventing member for preventing floating and scattering of a magnet of a rotor of a blower motor, and a rotor.

  A blower with a structure in which an impeller (blade) is directly attached to a rotor shaft portion of an electric motor that rotates at high speed (5000 rpm to 50000 rpm) does not require a speed increaser. Is also highly efficient and requires less power. However, a rotor rotating at a high speed with a structure in which a cylindrical magnet is fixed to the outer periphery of the rotor has a problem that the magnet on the outer periphery floats or scatters due to centrifugal force.

  Therefore, in order to solve the above problem, it is generally performed to prevent the magnet from rising and scattering by covering the entire outer peripheral surface of the magnet with a cylindrical reinforcing material.

  As this reinforcing material, there is a material made of so-called fiber reinforced resin (FRP) in which glass fiber or the like is impregnated with resin and hardened as disclosed in Patent Document 1, for example.

JP 2010-200440 A

  However, when the FRP reinforcing material prevents the floating and scattering of the magnet of the rotor that rotates at high speed, the fiber with low tensile elastic modulus such as glass fiber has a low rigidity of the entire FRP. It is affected and distortion and deformation occur.

  Furthermore, when the fiber is not arranged in the direction in which the rotor rotates, the FRP cannot obtain the strength against centrifugal force and cannot prevent the magnet from floating and scattering (FRP is the strength against the direction in which the fibers are not oriented). Because it is weak.)

  In addition, since FRP has a relatively low fiber content (fiber volume content is 40 to 60 vol%), it is assumed that a fiber having a high tensile elastic modulus is used and the fiber is arranged in the rotational direction of the rotor. However, the effect of preventing the floating and scattering of the magnet is not sufficient.

  That is, in order to prevent the floating and scattering of the magnet using FRP, a) using a fiber having a high tensile elastic modulus, b) arranging the fiber in the direction in which the rotor rotates, and c) the fiber of the FRP It is essential to increase the content.

  The present invention has been completed on the basis of the above-mentioned knowledge of the present inventors and the like, and is excellent in practicality that can achieve weight reduction of the rotor and can prevent the magnet from rising and scattering during high-speed rotation. A magnet floating and scattering prevention member and a rotor are provided.

  The gist of the present invention will be described with reference to the accompanying drawings.

  The magnet 1 is provided outside the magnet 2 of a rotor that has a shaft 1 and a magnet 2 formed by continuously connecting the divided bodies provided around the shaft 1 in a cylindrical shape, and rotates at 5000 rpm or more. This is a cylindrical magnet floating and scattering preventing member that prevents scatter and scattering, and this magnet floating and scattering preventing member 3 is a carbon formed by winding and laminating carbon fibers along the outer peripheral direction of the magnet 2. It is a thing made from fiber reinforced resin, and the volume content rate of the said carbon fiber concerns on the magnet floating and scattering prevention member characterized by being 75 vol% or more.

  2. The magnet lifting and scattering prevention member according to claim 1, wherein the carbon fiber has a tensile elastic modulus of 230 GPa or more.

  The magnet floating and scattering preventing member according to claim 2, wherein the carbon fiber has a tensile elastic modulus of 475 GPa or less.

  Further, in the magnet lifting and scattering prevention member according to any one of claims 1 to 3, the glass transition temperature of the matrix resin is 150 ° C or more, and the magnet lifting and scattering prevention member is characterized in that It is.

  Further, in the magnet lifting and scattering prevention member according to any one of claims 1 to 4, the winding angle of the carbon fiber is set to 85 ° or more and less than 90 ° with respect to the rotation axis of the shaft 1. The present invention relates to a magnet floating and scattering preventing member characterized by having

  The magnet floating and scattering prevention member according to any one of claims 1 to 5, wherein the carbon fiber is wound and laminated by a filament winding method. This relates to the prevention member.

  Further, in the magnet lifting and scattering prevention member according to any one of claims 1 to 6, the volume content of the carbon fiber is 85 vol% or less, and the magnet lifting and scattering prevention member is provided. Is.

  The magnet floating and scattering prevention member according to any one of claims 1 to 7, wherein the magnet 2 is fixed to the shaft 1 by an appropriate fixing method. It concerns the member.

  The magnet floating and scattering preventing member according to any one of claims 1 to 8, wherein the rotor is a rotor rotating at 50000 rpm or less, and the magnet floating and scattering preventing member is characterized in that is there.

  The magnet floating and scattering prevention member according to any one of claims 1 to 9, wherein the rotor is a rotor for an electric motor or a generator. Is.

  A rotor that rotates at a speed of 5000 rpm or more provided with a shaft 1 and a magnet 2 that is formed by continuously connecting divided bodies provided around the shaft 1 in a cylindrical shape. This invention relates to a rotor characterized in that the magnet lifting and scattering prevention member according to any one of the above items is provided.

  Since the present invention is configured as described above, it is possible to reduce the weight of the rotor and to prevent the floating and scattering of the magnet during high-speed rotation, and the magnet floating and scattering preventing member and the rotor excellent in practicality can be prevented. It becomes.

It is a schematic explanatory perspective view of a present Example. It is a schematic explanatory side view of a present Example. It is a schematic explanatory sectional drawing of a present Example. It is a schematic explanatory sectional drawing of embodiment of a present Example. It is a schematic explanatory sectional drawing of embodiment of a present Example. It is a schematic explanatory drawing explaining the introduction angle of carbon fiber. It is a table | surface which shows an experimental condition and an experimental result. It is a figure which shows the relationship between Vf of a present Example, and the margin factor with respect to required tension | tensile_strength.

  An embodiment of the present invention which is considered to be suitable will be briefly described with reference to the drawings showing the operation of the present invention.

  For example, the rotor provided in the blower motor is rotated at a high speed of 5000 rpm or more. At this time, the carbon fiber disposed along the outer circumferential direction of the magnet 2 sufficiently exhibits the resistance to centrifugal force, and the magnet 2 is firmly fixed to the shaft 1 to prevent the magnet 2 from rising and scattering well. be able to.

  In addition, since the volume content of the carbon fiber is as high as 75 vol% or more, the characteristics of the carbon fiber that is lightweight and highly elastic are emphasized, and weight reduction can be achieved while ensuring the overall rigidity.

  Therefore, in the present invention, the magnet 2 can be lifted well by firmly fixing the magnet 2 to the shaft 1 without being strained or deformed even at a high speed of 5000 rpm or more, as well as being lightweight. Thus, the magnet floating and scattering preventing member 3 that can prevent scattering and can rotate at high speed are obtained.

  Specific embodiments of the present invention will be described with reference to the drawings.

  This embodiment is provided outside the magnet 2 of a rotor having a shaft 1 and a magnet 2 formed by continuously connecting the divided bodies provided around the shaft 1 in a cylindrical shape and rotating at 5000 rpm or more. A cylindrical magnet floating and scattering preventing member that prevents the magnet 2 from floating and scattering, and the magnet floating and scattering preventing member 3 winds carbon fiber along the outer circumferential direction of the magnet 2. It is made of carbon fiber reinforced resin formed by laminating, and the volume content of the carbon fiber is 75 vol% or more.

  Specifically, a rotor of a blower that blows air with an impeller provided at an end of a rotor of an electric motor that rotates at 5000 rpm or more and 50000 rpm or less, provided with a stator that rotates the rotor in cooperation with the magnet 2 of the shaft 1. It is an example applied to.

  Each part will be specifically described.

  The shaft 1 is made of metal, and a columnar base member 4 made of metal concentric with the shaft 1 is fixed to the central portion of the shaft 1 in the axial direction. A plurality of tile-shaped magnets 2 are fixed to the outer peripheral surface of the base member 4 by an appropriate fixing method so as to form a cylindrical shape concentric with the shaft 1 as a whole (FIGS. 1 to 3). Therefore, the shaft 1 and the magnet 2 rotate integrally. In the present embodiment, the magnet 2 is attached so as to cover substantially the entire outer peripheral surface of the base member 4. As a method for fixing the magnet 2 to the base member 4, fixing with an adhesive (for example, epoxy), fixing with screws 7 and bolts as shown in FIG. 4 (see FIGS. 4A and 4C). ), Or fixing by winding the electrical insulating tape 8 or the like around (see FIG. 4B). 4A is an example in which a screw 7 is passed through the center of the magnet 2 and is fixed to the base member 4. FIG. 4C is a divided body of the magnet 2 through a presser plate 9. FIG. This is an example of fixing to the base member 4 through the screw 7 at the boundary portion. In FIG. 4C, the screw 7 passes through the diamond-shaped notch 10 formed by chamfering the corners of the adjacent magnets 2.

  About the base member 4 and the magnet 2, the thing of various shapes other than the shape shown in FIGS. 1-3 can be employ | adopted suitably. For example, as the base member 4, a cylindrical base member 4 having a length that is about half of the total length is connected near the center in the axial direction of the shaft 1, or the shaft 1 (the base member 4) is integrated. Can be adopted. Moreover, as the magnet 2, what connected the semicircle magnet 2 in the cylinder shape is employable. FIG. 5 shows a rotor mode in which the various base members 4 and magnets 2 described above are appropriately combined. 5A to 5F are longitudinal sectional views, and FIGS. 5G and 5H are transverse sectional views. 5A shows the present embodiment, FIG. 5B shows an example in which the shaft 1 and the base member 4 are integrated in FIG. 5A, and FIG. 5C shows the base member 4 and the magnet 2 in the shaft axial direction in FIG. (D) is an example in which the magnet 2 is divided into a large number in the shaft axial direction in (a), (e) is an example in which the base member 4 and the shaft 1 are integrated in (d), (f) is In (c), an example in which the magnet 2 is further divided into a large number in the shaft axis direction, (g) is an example in which the magnet 2 is divided into a semi-cylindrical shape in two upper and lower parts, and (h) is this embodiment.

  In the present embodiment, the magnet 2 is fitted so as to cover substantially the entire outer peripheral surface.

  Specifically, the present embodiment is made of a carbon fiber reinforced resin formed by accurately winding and laminating carbon fibers impregnated with a resin on the magnet 2 using a known filament winding method. Is formed by hoop winding with a fiber winding angle of 85 ° or more and less than 90 ° (more preferably 88 ° or more and less than 90 °).

  Therefore, the carbon fiber is disposed along the outer circumferential direction of the magnet 2 (substantially parallel to the rotation direction of the rotor), so that the resistance to centrifugal force is sufficiently exhibited.

  Moreover, the volume content (Vf) of the carbon fiber of a present Example is set to 75 vol% or more and 85 vol% or less. If it is less than 75 vol%, the characteristics of the carbon fiber are not fully utilized and the proof stress becomes insufficient. On the other hand, if it is larger than 85 vol%, the fibers are easily broken and the proof stress is insufficient.

  Here, in order to make Vf 75 vol% or more, the amount of resin impregnated in the fiber must be about 18 wt%, which is about half of the case of molding a general FRP. However, with this amount of resin, the amount of resin necessary to control the fiber orientation cannot be secured, and the fibers are likely to be scattered.

  In this regard, in this embodiment, when the carbon fiber is wound and laminated on the outer periphery of the magnet 2, the angle of introduction of the carbon fiber 6 drawn from the bobbin 5 into the magnet 2 is determined as shown in FIG. The yarn path is optimized by setting the positional relationship between the bobbin 5 and the winding part so as to be as close to 90 ° as possible with respect to one axis. Further, the tension applied to the fiber is optimized by making it uniform.

  Thereby, even if the amount of resin is reduced as much as possible in order to increase the volume content of the fiber as much as possible, the fiber orientation can be controlled without causing the fibers to be separated.

  Further, as described above, in order to wind the fiber around the magnet 2 on the circumference, the fiber must follow the curved surface of the magnet 2. This followability becomes better as the elongation of the fiber is larger. Here, when the base fiber is a glass fiber, the elongation is large and the followability is high, so that the fiber can be wound well around the magnet 2 on the circumference. On the other hand, the carbon fiber has an elongation of less than half that of the glass fiber and has low followability, so that it is generally difficult to wind the fiber well around the magnet 2 on the circumference. In the above, by optimizing the tension applied to the yarn path and the fiber as described above, even a fiber having low followability can be satisfactorily wound around the magnet 2 on the circumference.

  In this example, a resin having a glass transition temperature (Tg) of 150 ° C. or higher is used as a base material. Specifically, what consists of the mixture of the polyfunctional epoxy resin as a main ingredient and an acid anhydride type hardening | curing agent is employ | adopted. Therefore, rigidity can be maintained against heat generated by high-speed rotation, and the floating and scattering prevention of the magnet 2 can be achieved more reliably.

As the carbon fiber, density of 1.76 g / cm ³ or more 1.88 g / cm ³ or less, the tensile modulus to adopt the following 475GPa least 230 GPa. For example, it can be employed in manufactured by Toray Industries, Inc. T300 (density 1.76 g / cm ^3, tensile modulus 230 GPa) and, M50JB (density 1.88 g / cm ^3, tensile modulus 475GPa) and the like. The carbon fibers described above are PAN-based, but pitch-based carbon fibers having an equivalent tensile elastic modulus can also be used.

On the other hand, the glass fiber generally has a density of 2.54 g / cm ³ and a tensile elastic modulus of 7.0 GPa. When this is indicated by an index value (tensile modulus / density) indicating the balance between the tensile modulus and density, 7.0 / 2.54≈2.76. On the other hand, the index value of the carbon fiber of the present example is 230 / 1.76 to 475 / 1.88≈131 to 253. A higher index value indicates that the fiber has a better balance between lightness and tensile modulus. That is, the carbon fiber is a fiber significantly superior to glass fiber in terms of the balance between lightness and tensile elastic modulus, and can be said to be a base material suitable for the fiber base material of FRP used in the rotor.

  A mechanism in which the carbon fiber reinforced resin according to the above configuration has high rigidity will be described.

  The elastic modulus of FRP is calculated from the equation (Ef × Vf) + (Em × Vm). Here, Ef is the tensile modulus of the fiber, Vf is the volume content of the fiber, Em is the elastic modulus of the resin, and Vm is the volume content of the resin. If Vf is determined in the FRP, Ef is 3 orders or more larger than Em, and the elastic modulus of FRP greatly depends on the value of Ef × Vf (particularly Ef).

  The carbon fiber employed in this example has a tensile modulus of 475 GPa, for example, and the VRP of FRP is 75 vol% or more. Accordingly, the value of Ef × Vf is 475 × 0.75, which is 356.25 or more. On the other hand, when a general glass fiber is used, the tensile elastic modulus of the glass fiber is 7.0 GPa, and the average Vf (of FRP using the glass fiber) is 55 vol%. Thus, the value of Ef × Vf is 7.0 × 0.55 = 3.85.

  As described above, the carbon fiber reinforced resin according to the above configuration has a significantly higher elastic modulus than a general FRP using glass fibers, and is an excellent member as a high-speed rotating member of a rotor.

  Since the present embodiment is configured as described above, when the rotor provided in the motor that rotates at high speed is rotated at a high speed of 5000 rpm or higher, the carbon fiber disposed along the outer circumferential direction of the magnet 2 is sufficiently resistant to centrifugal force. As a result, the magnet 2 can be firmly fixed to the shaft 1 and the floating and scattering of the magnet 2 can be satisfactorily prevented.

In addition, since the volume content of the carbon fiber is as high as 75 vol% or more, the characteristics of the carbon fiber that is lightweight and highly elastic are emphasized, and weight reduction can be achieved while ensuring the overall rigidity.
Therefore, in this embodiment, the magnet 2 can be lifted well by firmly fixing the magnet 2 to the shaft 1 without being strained or deformed even at a high speed of 5000 rpm or more, as well as being lightweight. Thus, the magnet floating and scattering preventing member 3 capable of high-speed rotation can be prevented.

  An experimental example supporting the effect of the present embodiment will be described.

  FIG. 7 is a table showing experimental conditions and experimental results for evaluating the appearance of the rotor (such as the presence or absence of deformation) by changing the Vf of the magnet floating and scattering prevention member 3, the tensile modulus of the fiber, and the glass transition temperature. . All samples are formed by hoop winding using a filament winding method. Moreover, the matrix resin of the sample except the comparative example 3 is made into the mixture of a polyfunctional epoxy resin and an acid anhydride, and the comparative example 3 is made into the mixture of a bifunctional epoxy resin and an acid anhydride.

  From the experimental results, in Comparative Example 1 in which Vf is less than 75%, Comparative Example 2 in which glass fiber is used instead of carbon fiber, and Comparative Example 3 in which the glass transition temperature is less than 150 ° C., FRP breakage or magnet It was confirmed that the floating of the part would occur. On the other hand, it was confirmed that Examples 1 to 3 were not deformed and the magnet 2 could be firmly fixed to the shaft 1.

  FIG. 8 is a graph showing the relationship between Vf in the magnet lifting and scattering prevention member 3 of this embodiment and the margin ratio with respect to the required tension. The margin ratio with respect to the required tension is the relative value expressed as a percentage with the margin ratio with respect to the required tension as a reference (100%), which is the lower limit at which no distortion or deformation occurs when the rotational speed of the rotor is 5000 rpm. From the graph, it is possible to grasp Vf necessary for the margin ratio with respect to the necessary tension to exceed 100%, that is, Vf necessary for preventing distortion and deformation when the rotational speed of the rotor is 5000 rpm.

  Here, it can be confirmed from the graph that when Vf is 75.0% or more, the margin ratio to the required tension exceeds 100%. That is, when the rotational speed of the rotor is 5000 rpm and the Vf of the magnet lifting and scattering prevention member 3 is 75.0% or more (the magnet lifting and scattering prevention member 3 of this embodiment) is not distorted or deformed. It was confirmed that it did not occur. By preventing distortion and deformation, the magnet lifting and scattering prevention member 3 can firmly prevent the magnet 2 from rising and scattering by firmly fixing the magnet 2 to the shaft 1.

  From the above, according to the configuration of the present invention, it was confirmed that the magnet lifting and scattering preventing member 3 capable of satisfactorily preventing the lifting and scattering of the magnet 2 during high-speed rotation of the rotor can be obtained.

  The magnet lifting and scattering prevention member 3 and the rotor according to the present invention are not only a rotating electric machine such as an electric motor and a generator rotating at high speed, but also an industrial apparatus such as a blower, a blower, a compressor, a turbine, and a pump using these. It can be applied to a wide range of applications.

1 Shaft 2 Magnet 3 Magnet floating and scattering prevention member

Claims (11)

  It is provided outside the magnet of the rotor that has a shaft and a magnet formed by continuously connecting the divided bodies provided around the shaft in a cylindrical shape and rotates at 5000 rpm or more, and prevents the magnet from rising and scattering. A cylindrical magnet floating and scattering prevention member, which is made of carbon fiber reinforced resin formed by winding and laminating carbon fibers along the outer circumferential direction of the magnet. A magnet floating and scattering prevention member, wherein the carbon fiber has a volume content of 75 vol% or more.   The magnet lifting and scattering prevention member according to claim 1, wherein the carbon fiber has a tensile elastic modulus of 230 GPa or more.   The magnet floating and scattering preventing member according to claim 2, wherein the carbon fiber has a tensile elastic modulus of 475 GPa or less.   The magnet floating and scattering prevention member according to any one of claims 1 to 3, wherein the matrix resin has a glass transition temperature of 150 ° C or higher.   5. The magnet lifting and scattering prevention member according to claim 1, wherein a winding angle of the carbon fiber is set to be 85 ° or more and less than 90 ° with respect to a rotation axis of the shaft. Characteristic magnet lifting and scattering prevention member.   The magnet floating and scattering preventing member according to any one of claims 1 to 5, wherein the carbon fiber is wound and laminated by a filament winding method. .   The magnet lifting and scattering prevention member according to any one of claims 1 to 6, wherein the carbon fiber has a volume content of 85 vol% or less.   The magnet floating and scattering preventing member according to any one of claims 1 to 7, wherein the magnet is fixed to the shaft by an appropriate fixing method.   The magnet floating and scattering prevention member according to any one of claims 1 to 8, wherein the rotor is a rotor rotating at 50000 rpm or less.   The magnet floating and scattering prevention member according to any one of claims 1 to 9, wherein the rotor is a rotor for an electric motor or a generator.   A rotor that rotates at 5000 rpm or more provided with a shaft and a magnet formed by continuously connecting divided bodies provided around the shaft in a cylindrical shape, and the rotor according to any one of claims 1 to 10 A rotor characterized in that the magnet lifting and scattering prevention member is provided.

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