Motor and pump equipment

Abstract

This prevents rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor. [Solution] In this motor, the rotor 6 comprises a drive magnet 14 and a magnet holding member 15 to which the drive magnet 14 is attached on the outer circumference. The magnet holding member 15 has a magnet contact portion 15d to which the magnet-side contact surface, which is one end face of the drive magnet 14 in the axial direction of the rotor 6, contacts the holding member-side contact surface. The magnet contact portion 15d has a convex portion 15g that protrudes toward the drive magnet 14 from the holding member-side contact surface, and the drive magnet 14 has a recess 14c that is recessed in the axial direction of the rotor 6 from the magnet-side contact surface and in which the convex portion 15g is located. On the side surface of the recess 14c in the circumferential direction of the rotor 6, a projection is formed that contacts the side surface of the convex portion 15g in the circumferential direction of the rotor 6 with a predetermined contact pressure.

Description

Technical Field

[0001] The present invention relates to a motor and a pump device.

Background Art

[0002] Conventionally, a motor incorporated and used in a pump device is known (see, for example, Patent Document 1). The motor described in Patent Document 1 includes a rotor disposed on the inner peripheral side of a cylindrical stator. The rotor includes a cylindrical portion that holds a cylindrical drive magnet (drive magnet). An annular seat portion that extends in the radial direction of the rotor is formed on the outer peripheral side of the cylindrical portion. A portion of the cylindrical portion on one side in the axial direction of the rotor with respect to the seat portion is a magnet holding portion (magnet holding portion) that fits inside the inner circumference of the drive magnet and holds the drive magnet. One end face of the drive magnet in the axial direction of the rotor is in contact with one face of the seat portion.

[0003] In the motor described in Patent Document 1, a plurality of ribs extending in the axial direction of the rotor are formed on the outer peripheral surface of the magnet holding portion. The drive magnet is press-fitted into the magnet holding portion so as to contact the plurality of ribs from the outside in the radial direction of the rotor. A convex portion protruding in the axial direction is formed on one face of the seat portion. A concave portion formed on one end face of the drive magnet in the axial direction of the rotor fits into the convex portion. In the motor described in Patent Document 1, the position of the drive magnet with respect to the magnet holding portion in the circumferential direction of the rotor is defined by the convex portion and the concave portion. Further, rotation of the drive magnet with respect to the magnet holding portion is prevented by the convex portion and the concave portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the motor described in Patent Document 1, a gap may occur between the convex portion and the concave portion in the circumferential direction of the rotor due to the influence of the dimensional tolerance of the convex portion formed on the seat and the dimensional tolerance of the concave portion formed on the drive magnet. In the motor described in Patent Document 1, since the drive magnet is press-fitted into the magnet holder, even if a gap occurs between the convex portion and the concave portion in the circumferential direction of the rotor, it is possible to prevent the drive magnet from rattling relative to the magnet holder in the circumferential direction of the rotor.

[0006] On the other hand, in the motor described in Patent Document 1, even if a gap occurs between the convex and concave portions in the circumferential direction of the rotor, it is necessary to bring the inner surface of the drive magnet and the outer surfaces of the multiple ribs into contact with a predetermined contact pressure in order to prevent rattling of the drive magnet relative to the magnet holder in the circumferential direction of the rotor. In order to ensure that the inner surface of the drive magnet and the outer surfaces of the multiple ribs are reliably brought into contact with a predetermined contact pressure, the dimensional tolerances of the drive magnet and the magnet holder must be made stricter. Therefore, in the motor described in Patent Document 1, the cost of components such as the drive magnet may be high.

[0007] Therefore, an object of the present invention is to provide a motor that has a rotor having a cylindrical drive magnet and a magnet holding member to which the drive magnet is attached on the outer circumference, and that can prevent rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor, while also being able to reduce the component costs of the drive magnet and the magnet holding member. Another object of the present invention is to provide a pump device equipped with such a motor. [Means for solving the problem]

[0008] To solve the above problems, a motor according to one aspect of the present invention comprises a rotor and a stator formed in a cylindrical shape and arranged on the outer circumference of the rotor, the rotor comprises a cylindrical drive magnet and a cylindrical magnet holding member to which the drive magnet is attached on the outer circumference, the axial direction of the cylindrical drive magnet and the axial direction of the cylindrical magnet holding member coincide with the axial direction of the rotor, the magnet holding member has a magnet contact portion to which the magnet-side contact surface, which is one end face of the drive magnet in the axial direction of the rotor, contacts the holding member-side contact surface, and either the drive magnet or the magnet contact portion has a magnet-side contact surface or a magnet-side contact surface that is more efficient for the drive magnet and the magnet A convex portion is formed that protrudes in the axial direction of the rotor toward the other side of either the contact portion, and a recess is formed in either the drive magnet or the other side of the magnet contact portion, which is recessed in the axial direction of the rotor from the magnet-side contact surface or the holding member-side contact surface, and the convex portion is positioned thereon, thereby restricting the movement of the drive magnet relative to the magnet contact portion in the circumferential direction of the rotor by the convex portion and recess, and a projection is formed on the side surface of the convex portion in the circumferential direction of the rotor that contacts the side surface of the recess in the circumferential direction of the rotor with a predetermined contact pressure, or a projection is formed on the side surface of the recess in the circumferential direction of the rotor that contacts the side surface of the convex portion in the circumferential direction of the rotor with a predetermined contact pressure.

[0009] In this embodiment of the motor, a convex portion is formed on either the magnetic contact portion of the magnet holding member that holds the drive magnet or the drive magnet, projecting in the axial direction of the rotor toward the other side of the drive magnet or the magnetic contact portion. A recess is formed on the other side of the drive magnet or the magnetic contact portion, recessing in the axial direction of the rotor from the contact surface on the magnet side or the contact surface on the holding member side, and the convex portion is positioned thereon. Furthermore, in this embodiment, a projection is formed on the side surface of the convex portion in the circumferential direction of the rotor, contacting the side surface of the recess in the circumferential direction of the rotor with a predetermined contact pressure, or a projection is formed on the side surface of the recess in the circumferential direction of the rotor, contacting the side surface of the convex portion in the circumferential direction of the rotor with a predetermined contact pressure.

[0010] Therefore, in this embodiment, even if the dimensional tolerances of the drive magnet and the magnet holding member are made somewhat loose, it is possible to prevent rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor by the side surfaces of the protrusions and recesses that contact with a predetermined contact pressure in the circumferential direction of the rotor, or by the side surfaces of the protrusions and convexes that contact with a predetermined contact pressure in the circumferential direction of the rotor. Consequently, in this embodiment, even if it is possible to prevent rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor, it is possible to reduce the component costs of the drive magnet and the magnet holding member.

[0011] The motor of this embodiment can be used, for example, in a pump device comprising an impeller that rotates together with a rotor, and a pump chamber through which the impeller and rotor are arranged and through which fluid passes. In this pump device, it is possible to prevent rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor, while reducing the component costs of the drive magnet and the magnet holding member. [Effects of the Invention]

[0012] As described above, in one aspect of the present invention, in a motor equipped with a rotor having a cylindrical drive magnet and a magnet holding member to which the drive magnet is attached on the outer circumference, it is possible to prevent rattling of the drive magnet relative to the magnet holding member in the circumferential direction of the rotor, while also reducing the component costs of the drive magnet and the magnet holding member. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a cross-sectional view of a pump device according to an embodiment of the present invention. [Figure 2] Figure 2 is a perspective view of the impeller and rotor shown in Figure 1. [Figure 3] Figure 3 is a perspective view showing the magnet holding member and the second wing member shown in Figure 2 from different directions. [Figure 4] Figure 4 is a bottom view of the magnet holding member shown in Figure 3. [Figure 5] Figure 5 is a perspective view of the drive magnet shown in Figure 2. [Figure 6] Figure 6 is a plan view of the drive magnet shown in Figure 5. [Figure 7] Figure 7 is a side view illustrating the procedure for pressing the protrusion into the recess shown in Figure 2. [Figure 8] Figure 8 is a side view illustrating the procedure for pressing the protrusion into the recess shown in Figure 2. [Modes for carrying out the invention]

[0014] Embodiments of the present invention will be described below with reference to the drawings.

[0015] (Overall configuration of the pump system) Figure 1 is a cross-sectional view of a pump device 2 according to an embodiment of the present invention. Figure 2 is a perspective view of the impeller 3 and rotor 6 shown in Figure 1. In the following description, the side in the Z1 direction as shown in Figure 1 will be referred to as the "upper" side, and the side in the Z2 direction as shown in Figure 1, which is opposite the upper side, will be referred to as the "lower" side. Note that the "upper and lower directions" in the following description are defined for the sake of explanation and do not necessarily coincide with the direction of the vertical line (vertical direction).

[0016] The pump device 2 in this embodiment is a type of pump called a canned pump (canned motor pump), and is used, for example, to circulate a cooling liquid such as cooling water. The pump device 2 comprises an impeller 3, a motor 4 that rotates the impeller 3, and a circuit board 5 for controlling the motor 4. The motor 4 consists of a rotor 6 and a stator 7. The impeller 3, motor 4, and circuit board 5 are arranged inside a case body 11, which consists of a housing 8, a case 9 that covers the upper side of the housing 8, and a cover 10 that covers the lower side of the housing 8. The axial direction of the rotor 6 coincides with the vertical direction. That is, the vertical direction is the axial direction of the rotor 6.

[0017] The housing 8, the case 9, and the cover 10 are formed of resin. The case 9 is joined to the upper end portion of the housing 8 by ultrasonic welding or vibration welding, and the cover 10 is joined to the lower end portion of the housing 8 by ultrasonic welding or vibration welding. In the case 9, a fluid (specifically, a liquid) suction portion 9b and a fluid discharge portion 9c are formed. Inside the case body 11, a pump chamber 12 through which the fluid sucked from the suction portion 9b passes toward the discharge portion 9c is formed. The pump chamber 12 is defined by the housing 8 and the case 9. In the pump device 2, the fluid is sucked from above the pump device 2 and discharged in a direction orthogonal to the vertical direction.

[0018] The rotor 6 includes a cylindrical drive magnet 14, a magnet holding member 15 that holds the drive magnet 14, and a cylindrical sleeve 16 held by the magnet holding member 15. The drive magnet 14 and the sleeve 16 are formed in a cylindrical shape. The magnet holding member 15 is formed in a cylindrical shape. Specifically, the magnet holding member 15 is formed in a substantially cylindrical shape. The magnet holding member 15 is formed of resin.

[0019] The axial direction of the drive magnet 14, the axial direction of the magnet holding member 15, and the axial direction of the sleeve 16 coincide with the vertical direction. That is, the axial direction of the drive magnet 14, the axial direction of the magnet holding member 15, and the axial direction of the sleeve 16 coincide with the axial direction of the rotor 6. The drive magnet 14 is attached to the outer peripheral side of the magnet holding member 15, and the sleeve 16 is attached to the inner peripheral side of the magnet holding member 15. Specific configurations of the drive magnet 14 and the magnet holding member 15 will be described later.

[0020] The rotor 6 is rotatably supported on a fixed shaft 17 and rotates about the fixed shaft 17. The fixed shaft 17 is positioned such that its axial direction coincides with its vertical direction. The case 9 has a recess in which the upper end of the fixed shaft 17 is positioned. The lower end of the fixed shaft 17 is held in the housing 8. A portion of the fixed shaft 17 is positioned on the inner circumference side of the sleeve 16. A thrust bearing member 18 is attached to the fixed shaft 17, which contacts the upper end surface of the sleeve 16. In this embodiment, the sleeve 16 functions as the radial bearing of the rotor 6, and the sleeve 16 and the thrust bearing member 18 function as the thrust bearing of the rotor 6.

[0021] The impeller 3 is installed at the upper end of the rotor 6. The impeller 3 rotates together with the rotor 6. The impeller 3 and rotor 6 are located in the pump chamber 12. The impeller 3 comprises a first blade member 21 made of resin having a plurality of blades 21b arranged at a constant pitch in the circumferential direction of the rotor 6, and a second blade member 22 made of resin which is formed separately from the first blade member 21 and to which the first blade member 21 is fixed. In this embodiment, the impeller 3 is composed of the first blade member 21 and the second blade member 22.

[0022] The first blade member 21 is fixed to the upper side of the second blade member 22. The first blade member 21 is composed of a plurality of blades 21b and a top plate portion 21c to which the upper ends of the plurality of blades 21b are connected. The second blade member 22 is integrally formed with the magnet holding member 15 by injection molding. That is, the magnet holding member 15 and the second blade member 22 are a single integrally molded resin part. The second blade member 22 is formed in a flange shape that widens radially outward from the upper end of the magnet holding member 15. Alternatively, the second blade member 22 may be formed separately from the magnet holding member 15 and fixed to the upper end of the magnet holding member 15.

[0023] The stator 7 is formed in a cylindrical shape. Specifically, the stator 7 is formed in a substantially cylindrical shape. The stator 7 is located on the outer circumference side of the rotor 6. The stator 7 is positioned so that its axial direction coincides with its vertical direction. The stator 7 comprises a drive coil 23, a stator core 24, and an insulator 25. The stator core 24 comprises an annular outer ring portion and a plurality of salient pole portions that protrude radially inward from the outer ring portion toward the rotor 6. The tip surfaces of the salient pole portions (radially inward surfaces of the rotor 6) face the outer surface of the drive magnet 14 via a cylindrical portion 8b, which will be described later and constitutes a part of the housing 8. The insulator 25 is made of an insulating material such as resin. The drive coil 23 is wound around the salient pole portions of the stator core 24 via the insulator 25.

[0024] As described above, the housing 8 is made of resin. The housing 8 is integrally formed with the stator 7 so as to cover the drive coil 23, the stator core 24, and the insulator 25. In this embodiment, the housing 8 is integrally formed with the stator 7 by insert molding. The housing 8 includes a cylindrical portion 8b positioned between the tip surface of the salient pole of the stator core 24 and the outer circumferential surface of the drive magnet 14, and a bottom portion 8c that closes the lower end of the cylindrical portion 8b. The circuit board 5 is positioned below the bottom portion 8c.

[0025] The circuit board 5 is a rigid substrate such as a glass epoxy substrate and is formed in a flat plate shape. The circuit board 5 is positioned so that its thickness direction and vertical direction coincide. The circuit board 5 is also positioned outside the pump chamber 12. The circuit board 5 is fixed to the housing 8 by fixing screws 26. A drive coil 23 is electrically connected to the circuit board 5. The housing 8 serves to prevent fluid from the pump chamber 12 from flowing into the locations where the stator 7 and circuit board 5 are positioned. The cover 10 is fixed to the lower end of the housing 8 so as to cover the circuit board 5 from below.

[0026] (Configuration of magnet holding member and driving magnet) Figure 3 is a perspective view showing the magnet holding member 15 and the second wing member 22 shown in Figure 2 from different directions. Figure 4 is a bottom view of the magnet holding member 15 shown in Figure 3. Figure 5 is a perspective view of the driving magnet 14 shown in Figure 2. Figure 6 is a plan view of the driving magnet 14 shown in Figure 5. Figures 7 and 8 are side views illustrating the procedure for press-fitting the protrusion 15g into the recess 14c shown in Figure 2.

[0027] In the following explanation, the clockwise direction when viewed from above (CW direction in Figures 4 and 6) will be referred to as the "clockwise direction," and the opposite direction to the clockwise direction (CCW direction in Figures 4 and 6) will be referred to as the "counterclockwise direction." In this embodiment, the rotor 6 rotates in one direction relative to the stator 7. Specifically, the rotor 6 rotates only in the clockwise direction relative to the stator 7. That is, in the pump device 2, when the rotor 6 rotates clockwise relative to the stator 7, fluid is discharged from the discharge section 9c. The counterclockwise direction (CCW direction) in this embodiment is the "counter-rotation direction," which is the opposite direction to the rotation direction of the rotor 6 relative to the stator 7.

[0028] As described above, the magnet holding member 15 is formed in a substantially cylindrical shape. The magnet holding member 15 comprises a first cylindrical portion 15b which constitutes the lower part of the magnet holding member 15, a second cylindrical portion 15c which constitutes the upper part of the magnet holding member 15, and a flange-shaped magnet contact portion 15d which is positioned between the first cylindrical portion 15b and the second cylindrical portion 15c in the vertical direction (i.e., positioned at an intermediate position in the vertical direction of the magnet holding member 15). In this embodiment, the magnet holding member 15 is composed of the first cylindrical portion 15b, the second cylindrical portion 15c, and the magnet contact portion 15d.

[0029] The first cylindrical portion 15b and the second cylindrical portion 15c are formed in a cylindrical shape. The outer diameter of the second cylindrical portion 15c is larger than the outer diameter of the first cylindrical portion 15b. The second blade member 22 is connected to the upper end of the second cylindrical portion 15c. The magnetic contact portion 15d is formed in a flange shape that widens radially outward from the rotor 6. The magnetic contact portion 15d is formed in a flat plate shape with the vertical direction as the thickness direction. The magnetic contact portion 15d is also formed in an annular shape. The outer diameter of the magnetic contact portion 15d is larger than the outer diameter of the second cylindrical portion 15c.

[0030] The drive magnet 14 is positioned on the outer circumference of the first cylindrical portion 15b. Multiple ribs 15e are formed on the outer circumference of the first cylindrical portion 15b, which contact the inner circumference of the drive magnet 14. The ribs 15e are formed in a straight line extending in the vertical direction. The multiple ribs 15e are formed at a constant pitch in the circumferential direction of the rotor 6. The inner circumference of the lower end of the drive magnet 14 is crimped and fixed to the lower end of the first cylindrical portion 15b.

[0031] The upper end surface of the drive magnet 14 is in contact with the lower surface of the magnet contact portion 15d. In this embodiment, the upper end surface of the drive magnet 14 is the magnet-side contact surface 14b. The lower surface of the magnet contact portion 15d is the holding member-side contact surface 15f, which the magnet-side contact surface 14b contacts. That is, the magnet contact portion 15d has a holding member-side contact surface 15f that the magnet-side contact surface 14b contacts. The outer diameter of the drive magnet 14 is approximately equal to the outer diameter of the magnet contact portion 15d.

[0032] The magnetic contact portion 15d has a protrusion 15g that projects downward from the contact surface 15f on the holding member side. That is, the magnetic contact portion 15d has a protrusion 15g that projects vertically toward the drive magnet 14 from the contact surface 15f on the holding member side. In this embodiment, three protrusions 15g are formed on the lower surface of the magnetic contact portion 15d. The three protrusions 15g are arranged at a constant pitch in the circumferential direction of the rotor 6. Furthermore, the protrusions 15g are formed in a rectangular parallelepiped shape that extends radially from the rotor 6. That is, the magnetic contact portion 15d has three protrusions 15g arranged radially. Note that the number of protrusions 15g formed on the magnetic contact portion 15d may be one, two, or four or more.

[0033] When viewed from above, the outer shape of the protrusion 15g is rectangular, with the radial direction of the rotor 6 as the direction of the longer side. That is, the side surface of the protrusion 15g in the circumferential direction of the rotor 6 is a plane perpendicular to the circumferential direction. The lower surface of the protrusion 15g is a plane perpendicular to the vertical direction. The outer end face of the protrusion 15g in the radial direction of the rotor 6 constitutes part of the outer circumferential surface of the magnet contact portion 15d. The inner end face of the protrusion 15g in the radial direction of the rotor 6 is connected to the outer circumferential surface of the first cylindrical portion 15b. That is, the protrusion 15g is formed in the radial direction of the rotor 6 between the outer circumferential surface of the first cylindrical portion 15b and the outer circumferential surface of the magnet contact portion 15d.

[0034] A second protrusion 15h is formed on the inner end portion of the radial protrusion 15g of the rotor 6, protruding downward from the protrusion 15g. That is, the magnet contact portion 15d has a second protrusion 15h that protrudes vertically from the protrusion 15g toward the drive magnet 14. The second protrusion 15h is formed in the shape of a rectangular parallelepiped. The upper end of the second protrusion 15h is connected to the lower surface of the protrusion 15g. The lower end surface of the second protrusion 15h is a plane perpendicular to the vertical direction.

[0035] The inner end of the second protrusion 15h in the radial direction of the rotor 6 is connected to the outer circumferential surface of the first cylindrical portion 15b. The side surface of the second protrusion 15h in the circumferential direction of the rotor 6 is a plane perpendicular to the circumferential direction. The width of the second protrusion 15h in the circumferential direction of the rotor 6 is equal to the width of the protrusion 15g in the circumferential direction of the rotor 6. The side surface of the second protrusion 15h in the circumferential direction of the rotor 6 is coplanar with the side surface of the protrusion 15g in the circumferential direction of the rotor 6.

[0036] The lower end surface of the second protrusion 15h has chamfered edges at both ends in the circumferential direction of the rotor 6. The clockwise end of the lower end surface of the protrusion 15g has also been chamfered. On both sides of the protrusion 15g and the second protrusion 15h in the circumferential direction of the rotor 6, recesses 15k are formed that are recessed upward from the contact surface 15f on the holding member side. The recesses 15k are formed in the shape of a rectangular groove parallel to the protrusion 15g. The recesses 15k are formed in the radial direction of the rotor 6 between the outer circumferential surface of the first cylindrical portion 15b and the outer circumferential surface of the magnet contact portion 15d.

[0037] The drive magnet 14 is a resin magnet (plastic magnet) manufactured by mixing magnetic powder with resin and molding it. The hardness of the drive magnet 14 is lower than the hardness of the resin magnet holding member 15. In this embodiment, the drive magnet 14 is made of a low-hardness material with lower hardness than the magnet holding member 15. The drive magnet 14 has a recess 14c formed therein that is recessed downward from the magnet-side contact surface 14b, which is the upper end surface of the drive magnet 14. That is, the drive magnet 14 has a recess 14c formed therein that is recessed vertically from the magnet-side contact surface 14b.

[0038] In this embodiment, three recesses 14c are formed on the magnet-side contact surface 14b. That is, the same number of recesses 14c as the number of protrusions 15g are formed on the drive magnet 14. The three recesses 14c are arranged at a constant pitch in the circumferential direction of the rotor 6. Furthermore, the recesses 14c are formed in the shape of a square groove extending in the radial direction of the rotor 6, and the drive magnet 14 has three recesses 14c arranged radially. The outer ends of the recesses 14c in the radial direction of the rotor 6 are connected to the outer circumferential surface of the drive magnet 14. The inner ends of the recesses 14c in the radial direction of the rotor 6 are connected to the inner circumferential surface of the drive magnet 14. That is, the recesses 14c are formed between the outer circumferential surface and the inner circumferential surface of the drive magnet 14 in the radial direction of the rotor 6.

[0039] The bottom surface (lower surface) of the recess 14c is a plane perpendicular to the vertical direction. The sides 14d and 14e of the recess 14c in the circumferential direction of the rotor 6 are planes perpendicular to the circumferential direction. In this embodiment, side 14d constitutes the clockwise side of the recess 14c, and side 14e constitutes the counterclockwise side of the recess 14c. A second recess 14f is formed at the inner end portion of the recess 14c in the radial direction of the rotor 6, recessing below the recess 14c. That is, the drive magnet 14 has a second recess 14f that is recessed vertically below the recess 14c. The outer shape of the second recess 14f when viewed from the radial direction of the rotor 6 is rectangular.

[0040] The inner end of the second recess 14f in the radial direction of the rotor 6 is connected to the inner circumferential surface of the drive magnet 14. The lower surface of the second recess 14f is a plane perpendicular to the vertical direction. The side surface of the second recess 14f in the circumferential direction of the rotor 6 is a plane perpendicular to the circumferential direction. The width of the second recess 14f in the circumferential direction of the rotor 6 is equal to the width of the recess 14c in the circumferential direction of the rotor 6. The side surface of the second recess 14f in the circumferential direction of the rotor 6 is coplanar with the side surfaces 14d and 14e of the recess 14c.

[0041] The protrusion 15g of the magnetic contact portion 15d is positioned in the recess 14c. That is, the protrusion 15g is fitted into the recess 14c. In this embodiment, the movement of the drive magnet 14 relative to the magnetic contact portion 15d in the circumferential direction of the rotor 6 is restricted by the protrusion 15g and the recess 14c. A gap is formed between the bottom surface of the recess 14c and the lower surface of the protrusion 15g. A projection 14g is formed on the side surface 14e of the recess 14c that contacts the side surface of the protrusion 15g in the circumferential direction of the rotor 6 (specifically, the counterclockwise side surface of the protrusion 15g) with a predetermined contact pressure. On the other hand, no projection 14g is formed on the side surface 14d of the recess 14c. That is, in the recess 14c, the projection 14g is formed only on the counterclockwise (i.e., counter-rotation) side surface 14e.

[0042] Before the protrusion 15g is fitted into the recess 14c, the projection 14g is formed in the shape of a semi-cylindrical rod extending in the vertical direction. Also, before the protrusion 15g is fitted into the recess 14c, the lower end of the projection 14g is chamfered. Multiple projections 14g are formed on the side surface 14e of the recess 14c, spaced apart in the radial direction of the rotor 6. In this embodiment, three projections 14g are formed on the side surface 14e. As described above, the projections 14g are in contact with the counterclockwise side surface of the protrusion 15g with a predetermined contact pressure. Also, the side surface 14d of the recess 14c is in contact with the clockwise side surface of the protrusion 15g with a predetermined contact pressure. In other words, the protrusion 15g is press-fitted into the recess 14c.

[0043] The second protrusion 15h of the magnetic contact portion 15d is positioned in the second recess 14f. A gap is formed between the lower surface of the second recess 14f and the lower surface of the second protrusion 15h. The clockwise side surface of the second protrusion 15h is in contact with the clockwise side surface of the second recess 14f. On the other hand, a gap is formed between the counterclockwise side surface of the second protrusion 15h and the counterclockwise side surface of the second recess 14f. In this embodiment, before moving the driving magnet 14 upward relative to the magnetic contact portion 15d and pressing the protrusion 15g into the recess 14c, the magnetic contact portion 15d and the driving magnet 14 are positioned in the circumferential direction of the rotor 6 using the second protrusion 15h and the second recess 14f.

[0044] For example, when press-fitting the protrusion 15g into the recess 14c, the drive magnet 14 and the magnet holding member 15 are inverted vertically, as shown in Figures 7 and 8. First, as shown in Figure 7, the drive magnet 14 is moved to the lower side of the magnet holding member 15, so that the first cylindrical portion 15b of the magnet holding member 15 is positioned on the inner circumference side of the drive magnet 14, and the magnet-side contact surface 14b is placed on the end face of the second protrusion 15h. Then, the drive magnet 14 is rotated relative to the magnet contact portion 15d.

[0045] When the drive magnet 14 rotates to a position where the second protrusion 15h and the second recess 14f coincide in the circumferential direction of the rotor 6, the second protrusion 15h fits into the recess 14c and the second recess 14f, and the drive magnet 14 lowers to a position where the projection 14g and the protrusion 15g come into contact, as shown in Figure 8. For example, the drive magnet 14 lowers by about 1 mm. When the drive magnet 14 lowers to a position where the projection 14g and the protrusion 15g come into contact, the magnet contact portion 15d and the drive magnet 14 are positioned in the circumferential direction of the rotor 6. In this state, if the drive magnet 14 is pushed down further, the protrusion 15g is pressed into the recess 14c.

[0046] (Main effects of this form) As described above, in this embodiment, a protrusion 15g is formed on the magnetic contact portion 15d of the magnet holding member 15, and a recess 14c into which the protrusion 15g fits is formed on the driving magnet 14. Furthermore, in this embodiment, a projection 14g is formed on the side surface 14e of the recess 14c, which contacts the side surface of the protrusion 15g in the circumferential direction of the rotor 6 with a predetermined contact pressure.

[0047] Therefore, in this embodiment, even if the dimensional tolerances of the drive magnet 14 and the magnet holding member 15 are made somewhat loose, the protrusions 14g and the sides of the convex portion 15g that contact the rotor 6 with a predetermined contact pressure in the circumferential direction make it possible to prevent the drive magnet 14 from rattling with respect to the magnet contact portion 15d in the circumferential direction of the rotor 6. Thus, in this embodiment, even if it is possible to prevent the drive magnet 14 from rattling with respect to the magnet holding member 15 in the circumferential direction of the rotor 6, it is possible to reduce the component costs of the drive magnet 14 and the magnet holding member 15.

[0048] In this embodiment, the rotor 6 rotates only clockwise relative to the stator 7. Furthermore, in this embodiment, the projection 14g is formed only on the counterclockwise side surface 14e of the recess 14c. Therefore, in this embodiment, it is possible to prevent excessive load from being placed on the projection 14g when the rotor 6 rotates. In addition, in this embodiment, multiple projections 14g are formed on the side surface 14e, spaced apart in the radial direction of the rotor 6, so it is possible to prevent excessive load from being placed on a single projection 14g. Consequently, in this embodiment, it is possible to suppress wear and tear on the projections 14g.

[0049] In this embodiment, a projection 14g is formed on the driving magnet 14, which has a lower hardness than the magnet holding member 15. Therefore, in this embodiment, the projection 14g is more likely to be crushed when the convex portion 15g is pressed into the recess 14c. Consequently, in this embodiment, the process of pressing the convex portion 15g into the recess 14c can be easily performed.

[0050] In this embodiment, a second protrusion 15h is formed on the magnet contact portion 15d, and a second recess 14f is formed on the drive magnet 14 where the second protrusion 15h is positioned. Therefore, in this embodiment, as described above, before press-fitting the protrusion 15g into the recess 14c, it is possible to position the magnet contact portion 15d and the drive magnet 14 in the circumferential direction of the rotor 6 using the recess 14c, the second recess 14f, and the second protrusion 15h. Thus, in this embodiment, the press-fitting operation of the protrusion 15g into the recess 14c can be easily performed.

[0051] Furthermore, in this embodiment, with the magnet-side contact surface 14b placed on the end face of the second protrusion 15h, the drive magnet 14 is moved in the circumferential direction of the rotor 6 relative to the magnet holding member 15, positioning the magnet contact portion 15d and the drive magnet 14 in the circumferential direction of the rotor 6 by the recess 14c, the second recess 14f and the second protrusion 15h, and then the drive magnet 14 is moved vertically relative to the magnet contact portion 15d to press-fit the protrusion 15g into the recess 14c. In other words, in this embodiment, the press-fit operation of pressing the protrusion 15g into the recess 14c is made possible by the automatic assembly machine.

[0052] (Other embodiments) The above-described embodiment is merely one example of a preferred embodiment of the present invention, and is not limited thereto. Various modifications can be made without altering the essence of the present invention.

[0053] In the above-described embodiment, the number of projections 14g formed on the side surface 14e may be one. Also, in the above-described embodiment, projections 14g may be formed on the side surface 14d instead of, or in addition to, the side surface 14e. Furthermore, in the above-described embodiment, projections 14g may not be formed on the side surface 14e. In this case, projections that contact the side surface 14e of the recess 14c are formed on the side surface of the convex portion 15g in the circumferential direction of the rotor 6 (specifically, the counterclockwise side surface).

[0054] In the above-described embodiment, the driving magnet 14 may have a protrusion that extends upward from the magnet-side contact surface 14b, and the magnet contact portion 15d may have a recess that is recessed upward from the holding member-side contact surface 15f and where the protrusion of the driving magnet 14 is positioned. That is, the driving magnet 14 may have a protrusion that extends vertically from the magnet-side contact surface 14b toward the magnet contact portion 15d, and the magnet contact portion 15d may have a recess that is recessed vertically from the holding member-side contact surface 15f.

[0055] In this case, the movement of the drive magnet 14 relative to the magnet contact portion 15d in the circumferential direction of the rotor 6 is restricted by the convex portion of the drive magnet 14 and the concave portion of the magnet contact portion 15d. In this case, either a projection is formed on the side surface of the convex portion of the drive magnet 14 in the circumferential direction of the rotor 6, which contacts the side surface of the concave portion of the magnet contact portion 15d in the circumferential direction of the rotor 6 with a predetermined contact pressure, or a projection is formed on the side surface of the concave portion of the magnet contact portion 15d in the circumferential direction of the rotor 6, which contacts the side surface of the convex portion of the drive magnet 14 in the circumferential direction of the rotor 6 with a predetermined contact pressure.

[0056] In the above-described embodiment, a second protrusion 15h may be formed in the middle or outer end portion of the radial protrusion 15g of the rotor 6, and a second recess 14f on which the second protrusion 15h is positioned may be formed in the middle or outer end portion of the radial recess 14c of the rotor 6. Furthermore, in the above-described embodiment, a second protrusion 15h may not be formed on the magnet contact portion 15d. In this case, the second recess 14f is not formed on the drive magnet 14.

[0057] In the above-described configuration, the hardness of the drive magnet 14 may be higher than the hardness of the magnet holding member 15. That is, the magnet holding member 15 may be made of a low-hardness material with lower hardness than the drive magnet 14. Also, in the above-described configuration, the hardness of the drive magnet 14 and the hardness of the magnet holding member 15 may be equal. Furthermore, in the above-described configuration, the motor 4 may be used in devices other than the pump device 2.

[0058] (Configuration of this technology) Furthermore, this technology can be configured as follows: (1) comprising a rotor and a stator formed in a cylindrical shape and arranged on the outer circumference side of the rotor, The rotor comprises a cylindrical drive magnet and a cylindrical magnet holding member to which the drive magnet is attached on the outer circumference. The axial direction of the cylindrical drive magnet and the axial direction of the cylindrical magnet holding member coincide with the axial direction of the rotor. The magnet holding member includes a magnet contact portion where a holding member side contact surface is formed, which is the magnet side contact surface that contacts the end face of the drive magnet on one side in the axial direction of the rotor. A protrusion is formed on either the driving magnet or the magnetic contact portion, which protrudes in the axial direction of the rotor toward the other side of the driving magnet or the magnetic contact portion, compared to the contact surface on the magnet side or the contact surface on the holding member side. The other of the drive magnet and the magnet contact portion has a recess formed in the rotor that is recessed in the axial direction from the magnet-side contact surface or the holding member-side contact surface, and in which the protrusion is positioned. The convex portion and the concave portion restrict the movement of the drive magnet relative to the magnet contact portion in the circumferential direction of the rotor. A motor characterized in that a projection is formed on the side surface of the convex portion in the circumferential direction of the rotor, which contacts the side surface of the concave portion in the circumferential direction of the rotor with a predetermined contact pressure, or a projection is formed on the side surface of the concave portion in the circumferential direction of the rotor, which contacts the side surface of the convex portion in the circumferential direction of the rotor with a predetermined contact pressure. (2) The rotor rotates in one direction relative to the stator, If the direction opposite to the rotation direction of the rotor relative to the stator is defined as the counter-rotation direction, The motor according to (1), characterized in that the projection is formed only on the side surface in the counter-rotation direction of the convex portion or the concave portion on which the projection is formed. (3) The motor according to (1) or (2), characterized in that a plurality of projections are formed on the side surface of the convex or concave portion in the circumferential direction of the rotor, and are spaced apart in the radial direction of the rotor. (4) The driving magnet is made of a low-hardness material that is less hard than the magnet holding member, or the magnet holding member is made of a low-hardness material that is less hard than the driving magnet, The motor according to any one of (1) to (3), characterized in that the projection is formed in the low-hardness material. (5) The protrusion is formed on the magnetic contact portion, The recess is formed in the drive magnet, The motor according to any one of (1) to (4), characterized in that the projection is formed on the side surface of the recess in the circumferential direction of the rotor. (6) A second protrusion is formed on either the driving magnet or the magnetic contact portion, which protrudes more in the axial direction of the rotor than the protrusion toward the other side of the driving magnet or the magnetic contact portion. The motor according to any one of (1) to (5), characterized in that the other of the drive magnet and the magnet contact portion has a second recess formed therein, which is recessed in the axial direction of the rotor more than the recess and in which the second protrusion is positioned. (7) A pump device comprising a motor as described in any of (1) to (6), an impeller that rotates together with the rotor, and a pump chamber through which the impeller and the rotor are arranged and through which fluid passes.

[0059] In this technology, the rotor rotates in one direction relative to the stator, and the direction opposite to the rotor's rotation relative to the stator is considered the counter-rotation direction. In the convex or concave portions where the protrusions are formed, it is preferable that the protrusions are formed only on the side surface in the counter-rotation direction. This configuration makes it possible to prevent excessive load from being placed on the protrusions when the rotor rotates. Therefore, it is possible to suppress wear on the protrusions.

[0060] In this technology, it is preferable that multiple protrusions are formed on the side surface of a convex or concave portion in the circumferential direction of the rotor, spaced apart in the radial direction of the rotor. This configuration makes it possible to prevent excessive load from being placed on a single protrusion. Therefore, it is possible to prevent wear and tear on the protrusions.

[0061] In this technology, it is preferable that the driving magnet is made of a low-hardness material with lower hardness than the magnet holding member, or that the magnet holding member is made of a low-hardness material with lower hardness than the driving magnet, and the protrusion is made of the low-hardness material. With this configuration, when the protrusion is pressed into the recess to bring the side surface of the recess or the side surface of the convex part into contact with the protrusion at a predetermined contact pressure in the circumferential direction of the rotor, the protrusion becomes more easily crushed. Therefore, the work of pressing the convex part into the recess becomes easier.

[0062] In this technology, for example, the convex portion is formed on the magnetic contact portion, the concave portion is formed on the driving magnet, and the projection portion is formed on the side surface of the concave portion in the circumferential direction of the rotor.

[0063] In this technology, it is preferable that either the driving magnet or the magnetic contact portion has a second protrusion that protrudes more in the axial direction of the rotor than the convex portion toward the other side of the driving magnet or magnetic contact portion, and that the other side of the driving magnet or magnetic contact portion has a second recess that is recessed more in the axial direction of the rotor than the recess and where the second protrusion is located.

[0064] With this configuration, it becomes possible to position the magnet contact portion and the drive magnet in the circumferential direction of the rotor using the recess, the second recess, and the second protrusion, before moving the drive magnet in the axial direction of the rotor relative to the magnet contact portion to press the protrusion into the recess, in order to bring the side surface of the recess or the side surface of the protrusion into contact with the projection at a predetermined contact pressure in the circumferential direction of the rotor. Therefore, the work of press-fitting the protrusion into the recess becomes easier. Furthermore, with this configuration, it becomes possible to have the automatic assembly machine perform the operation of moving the drive magnet in the circumferential direction of the rotor relative to the magnet holding member to position the magnet contact portion and the drive magnet in the circumferential direction of the rotor using the recess, the second recess, and the second protrusion, and then moving the drive magnet in the axial direction of the rotor relative to the magnet contact portion to press-fit the protrusion into the recess. In other words, it becomes possible to have the automatic assembly machine perform the press-fitting operation of pressing the protrusion into the recess. [Explanation of Symbols]

[0065] 2. Pumping device 3-Paddle Wheel 4 motors 6 rotors 7 Status 12 Pump Room 14. Drive magnets (low hardness material) 14b Magnet side contact surface 14c recess 14f Second recess 14g protrusion 15 Magnet holding member 15d Magnet contact part 15f Holding member side contact surface 15g protrusion 15h Second protrusion CCW (Counter-Clockwise)

Claims

1. It comprises a rotor and a stator that is formed in a cylindrical shape and positioned on the outer circumference of the rotor, The rotor comprises a cylindrical drive magnet and a cylindrical magnet holding member to which the drive magnet is attached on the outer circumference. The axial direction of the cylindrical drive magnet and the axial direction of the cylindrical magnet holding member coincide with the axial direction of the rotor. The magnet holding member includes a magnet contact portion where a holding member side contact surface is formed, which is the magnet side contact surface that contacts the end face of the drive magnet on one side in the axial direction of the rotor. A protrusion is formed on either the driving magnet or the magnetic contact portion, which protrudes in the axial direction of the rotor toward the other side of the driving magnet or the magnetic contact portion, compared to the contact surface on the magnet side or the contact surface on the holding member side. The other of the drive magnet and the magnet contact portion has a recess formed in the rotor that is recessed in the axial direction from the magnet-side contact surface or the holding member-side contact surface, and in which the protrusion is positioned. The convex portion and the concave portion restrict the movement of the drive magnet relative to the magnet contact portion in the circumferential direction of the rotor. A motor characterized in that a projection is formed on the side surface of the convex portion in the circumferential direction of the rotor, which contacts the side surface of the concave portion in the circumferential direction of the rotor with a predetermined contact pressure, or a projection is formed on the side surface of the concave portion in the circumferential direction of the rotor, which contacts the side surface of the convex portion in the circumferential direction of the rotor with a predetermined contact pressure.

2. The rotor rotates in one direction relative to the stator, If the direction opposite to the rotation direction of the rotor relative to the stator is defined as the counter-rotation direction, The motor according to claim 1, characterized in that the projection is formed only on the side surface in the counter-rotation direction of the convex portion or the concave portion on which the projection is formed.

3. The motor according to claim 1 or 2, characterized in that a plurality of projections are formed on the side surface of the convex or concave portion in the circumferential direction of the rotor, and are arranged at intervals in the radial direction of the rotor.

4. The driving magnet is made of a low-hardness material with lower hardness than the magnet holding member, or the magnet holding member is made of a low-hardness material with lower hardness than the driving magnet. The motor according to claim 1 or 2, characterized in that the projection is formed in the low-hardness material.

5. The aforementioned protrusion is formed on the magnetic contact portion, The recess is formed in the drive magnet, The motor according to claim 1 or 2, characterized in that the projection is formed on the side surface of the recess in the circumferential direction of the rotor.

6. A second protrusion is formed on either the driving magnet or the magnetic contact portion, which protrudes more in the axial direction of the rotor than the protrusion toward the other side of the driving magnet or the magnetic contact portion. The motor according to claim 1 or 2, characterized in that the other of the drive magnet and the magnet contact portion has a second recess formed therein, which is recessed in the axial direction of the rotor more than the recess and on which the second protrusion is located.

7. A pump device comprising a motor according to claim 1 or 2, an impeller that rotates together with the rotor, and a pump chamber through which the impeller and the rotor are arranged and through which fluid passes.

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