Pump device

Abstract

To suppress reduction in form accuracy of a rotor when a drive magnet is fixed by thermal caulking, and to achieve miniaturization in an axial direction of a rotor.SOLUTION: A rotor 4 of a pump device 1 includes: a rotor member 40 having a first cylindrical part 41 extending in an axial direction; and a drive magnet 8 surrounding an outer periphery of the first cylindrical part 41, wherein a radial bearing 11 is held inside the first cylindrical part 41. The drive magnet 8 includes: a second cylindrical part 81 extending in the axial direction; and an annular rib 82 projecting from an end portion at the other side L2 in the axial direction of the second cylindrical part 81 to a radially inner side. The rotor member 40 includes: a seat part 42 projecting from the first cylindrical part 41 to a radially outer side and supporting an end portion on one side L1 in the axial direction of the second cylindrical part 81; and a caulking part 43 expanding from an end portion on the other side L2 in the axial direction of the first cylindrical part 41 to the radially outer side, and overlapping with the annular rib 82 from the other side L2 in the axial direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pump device including a rotor that rotates integrally with an impeller. [Background technology]

[0002] Patent Document 1 describes a pump device in which an impeller disposed in a pump chamber is rotated by a motor. The motor includes a rotor that rotates integrally with the impeller. The rotor includes a cylindrical portion that holds a cylindrical radial bearing inside, and a cylindrical drive magnet is fixed to the outer periphery of the cylindrical portion. The drive magnet is held between a seat portion that protrudes radially outward from the cylindrical portion and a crimped portion formed at the tip of the cylindrical portion.

[0003] The rotor is rotatably supported on a fixed shaft via a radial bearing. When the rotor rotates, friction and the like causes the radial bearing to heat up, and the drive magnet also heats up, causing problems such as a shortened component life and a deterioration in the magnetic properties of the drive magnet. In the pump device of Patent Document 1, the drive magnet is cooled by having the fluid in the pump chamber flow through the gap between the drive magnet and the cylindrical part of the rotor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-183753 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a rotor that has a structure in which a drive magnet is held between a seat provided on a cylindrical portion and a crimped portion, the end face of the drive magnet is covered by the crimped portion. If the radial thickness of the drive magnet is thin, the radial width of the end face of the drive magnet is narrow. As a result, the crimped portion may protrude to the outer periphery of the drive magnet, causing burrs, which may reduce the shape precision of the rotor.

[0006] In addition, the rotor has a radial bearing held inside the cylindrical portion, which is pressed axially against a receiving member such as a washer by the magnetic attractive force generated by the drive magnet. The drive magnet needs to have a size (volume) that can generate the magnetic attractive force necessary to press the radial bearing against the receiving member. For this reason, the drive magnet has a long axial dimension, which makes the rotor's axial dimension long as well.

[0007] Furthermore, when the fluid in the pump chamber is caused to flow into the gap between the cylindrical portion of the rotor and the drive magnet to cool the radial bearing and the drive magnet, there has been a demand for ensuring a sufficient flow rate in order to enhance the cooling effect.

[0008] In view of the above, an object of the present invention is to suppress a decrease in the shape accuracy of a rotor when a drive magnet is fixed by thermal caulking, and to reduce the size of the rotor in the axial direction.

[0009] Another object of the present invention is to form a flow passage with a high flow rate inside the drive magnet. [Means for solving the problem]

[0010] In order to solve the above problems, the pump device of the present invention includes a motor including a rotor and a stator surrounding an outer periphery of the rotor, and a pump having an axial direction along a rotation axis of the rotor. and an impeller disposed in a pump chamber provided on one side of the stator in the axial direction and rotating integrally with the rotor, the rotor comprising a rotor member having a first cylindrical portion extending in the axial direction, and a drive magnet surrounding an outer periphery of the first cylindrical portion, a radial bearing is held inside the first cylindrical portion, the drive magnet comprising a second cylindrical portion surrounding the outer periphery of the first cylindrical portion and extending in the axial direction, and an annular rib protruding radially inward from an end of the second cylindrical portion on the other side in the axial direction, the rotor member comprising a seat portion protruding radially outward from the first cylindrical portion and supporting an end of the second cylindrical portion on one side in the axial direction, and a crimp portion extending radially outward from the end of the first cylindrical portion on the other side in the axial direction and overlapping the annular rib from the other side in the axial direction.

[0011] According to the present invention, the drive magnet is held between the seat and the crimped portion provided on the first cylindrical portion of the rotor member. The drive magnet is provided with an annular rib that protrudes radially inward at an end portion located on the tip side (the side where the crimped portion is provided) of the first cylindrical portion. In this way, by providing the drive magnet with a portion (annular rib) that protrudes to the inner periphery side instead of making it a simple cylindrical shape, it is possible to ensure the volume and the necessary magnetic attraction force even if the axial length is shortened. In addition, since the annular rib is provided on the end portion on the side where the crimped portion is provided, the radial width of the end face that receives the crimped portion is large. Therefore, there is little risk that the crimped portion will protrude radially outward from the drive magnet, and therefore it is possible to suppress the deterioration of the shape accuracy of the rotor due to thermal crimping.

[0012] In the present invention, it is preferable that there is a radial gap between the first cylindrical portion and the second cylindrical portion, the gap functions as a flow channel through which the fluid in the pump chamber flows, and the other side of the flow channel in the axial direction is blocked by the annular rib and the crimped portion. In this way, the flow channel has a depth (diameter) according to the protruding dimension of the annular rib, so that the volume of the flow channel can be secured and a large amount of fluid can flow between the drive magnet and the first cylindrical portion. Therefore, the cooling effect of the radial bearing held inside the first cylindrical portion and the cooling effect of the drive magnet can be improved. Therefore, the shortening of the life of the parts and the deterioration of the magnetic properties of the drive magnet due to high temperatures can be suppressed.

[0013] In the present invention, it is preferable that a plurality of magnet-side ribs that protrude radially inward and extend in the axial direction are arranged in the circumferential direction on the inner peripheral surface of the second cylindrical portion, and the gaps between adjacent ribs in the circumferential direction function as the flow channel. In this way, the first cylindrical portion can be fitted inside the radially arranged magnet-side ribs, so that a flow channel with a large volume can be secured and the drive magnet can be assembled with high precision. In addition, the second cylindrical portion can be reinforced by the magnet-side ribs, so that the strength of the drive magnet can be increased.

[0014] In the present invention, it is preferable that the other end of the magnet-side rib in the axial direction is connected to the annular rib, whereby the second cylindrical portion and the annular rib are connected via the magnet-side rib, thereby increasing the strength of the drive magnet.

[0015] In the present invention, it is preferable that a plurality of rotor member-side ribs that protrude radially outward and extend in the axial direction are arranged in the circumferential direction on the outer circumferential surface of the first cylindrical portion, and the flow channel is defined in the circumferential direction by the tip end surface of the magnet-side rib abutting against the tip end surface of the rotor member-side rib. In this way, by forming ribs not only on the drive magnet but also on the rotor member, the depth (radial width) of the flow channel can be made larger. Therefore, the volume of the flow channel can be secured.

[0016] In the present invention, an inlet communicating with the flow channel is provided between the seat portion and the second cylindrical portion. In this way, the fluid in the pump chamber can be made to flow into the flow passage groove through the gap on the outer circumferential side of the drive magnet.

[0017] In the present invention, the flow channel includes a first groove portion extending in the axial direction, a second groove portion extending in the axial direction on the rear side of the first groove portion in the rotation direction of the rotor, and a third groove portion extending in the circumferential direction and connecting the other end of the first groove portion and the second groove portion in the axial direction, and the inlet is preferably connected to the first groove portion. In this way, the flow channel has a shape in which the first groove portion and the second groove portion extending in the axial direction are connected to each other by the third groove portion in a shape (U-shape) that is folded back once in the axial direction. This makes it possible to increase the area in contact with the fluid compared to a case where a flow channel is simply provided in a straight line, and thus the cooling effect can be improved. In addition, when the rotor rotates, the fluid flows to the rear side in the rotation direction due to inertia force, so that the inlet side becomes negative pressure and the fluid in the pump chamber continues to flow in. Therefore, the cooling effect can be improved.

[0018] In the present invention, it is preferable that the seat portion has a recess recessed toward one side in the axial direction, and the inlet is a gap between a bottom surface of the recess and an end surface of the second cylindrical portion on one side in the axial direction. In this way, a flow path that communicates between the outer periphery and the inner periphery of the drive magnet can be formed with a simple structure without providing a through hole in a part.

[0019] In the present invention, it is preferable that a first protrusion protruding from the bottom surface of the recess is fitted into a first recess provided on the end surface of the drive magnet, and both circumferential sides of the first protrusion in the recess form the inflow ports in two locations. In this way, a rotation stopper can be provided to prevent the drive magnet from rotating relative to the rotor member. Also, since the angular position of the inflow port can be adjusted with respect to the drive magnet, the inflow port can be provided at an appropriate angular position.

[0020] In the present invention, the impeller includes a flange portion provided at one end of the rotor member in the axial direction and an impeller fixed to the flange portion from one side in the axial direction, the first cylindrical portion includes a connection portion extending in the axial direction between the flange portion and the seat portion, and a magnet holding portion fitted inside the drive magnet, the radial bearing is held inside the magnet holding portion, the inside of the connection portion is a first space through which the fluid of the pump chamber flows through a through hole that penetrates the connection portion in the radial direction, and the first space is preferably connected to a bearing cooling passage that penetrates the magnet holding portion in the axial direction. In this way, the fluid of the pump chamber can be made to flow into the bearing cooling passage from a position (first space) different from the outer circumferential side of the drive magnet. Therefore, the cooling effect can be improved. Effect of the Invention

[0021] According to the present invention, even if the axial length of the drive magnet is shortened, the volume can be secured to ensure the necessary magnetic attraction force. Also, since an annular rib is provided at the end where the crimped portion is provided, the radial width of the end face that receives the crimped portion is large. Therefore, there is little risk that the crimped portion will protrude radially outward from the drive magnet, and the deterioration of the rotor shape accuracy due to thermal crimping can be suppressed.

[0022] Furthermore, in the present invention, a flow passage groove with a depth according to the protruding dimension of the annular rib can be secured inside the drive magnet, so a flow passage with a high flow rate can be formed. This improves the cooling effect of the radial bearing held inside the first cylindrical portion and the cooling effect of the drive magnet. This makes it possible to suppress the shortening of the lifespan of parts and the deterioration of the magnetic properties of the drive magnet due to high temperatures. [Brief description of the drawings]

[0023] [Figure 1] 1 is an external perspective view of a pump device to which the present invention is applied; [Diagram 2] 2 is a cross-sectional view of the pump device shown in FIG. 1 taken along a plane including a rotation axis. [Diagram 3] FIG. [Figure 4] FIG. 2 is an exploded perspective view of a rotor and a radial bearing as viewed from one side in the axial direction. [Diagram 5] 4 is an exploded perspective view of the rotor and the radial bearing as viewed from the other axial side. FIG. [Figure 6] FIG. [Figure 7] 2 is a partial cross-sectional view of a rotor, a radial bearing, and a support shaft cut along a plane including a rotation axis. [Figure 8] 8 is a cross-sectional perspective view of the rotor, the radial bearing, and the support shaft cut by a plane perpendicular to the rotation axis (a view cut at the position AA in FIG. 7). [Figure 9] 8 is a cross-sectional perspective view of the rotor, the radial bearing, and the support shaft cut by a plane perpendicular to the rotation axis (cut at position BB in FIG. 7). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, a pump device 1 according to an embodiment of the present invention will be described with reference to the drawings. In this specification, the axial direction means the direction in which the rotation axis L of the motor 10 extends. One side in the axial direction is designated as L1, and the other side in the axial direction is designated as L2. The radial direction on the radially inner side and the radially outer side means the radial direction centered on the rotation axis L. The circumferential direction means the rotation direction centered on the rotation axis L.

[0025] (Overall composition) FIG. 1 is an external perspective view of a pump device 1 to which the present invention is applied. FIG. 2 is a cross-sectional view of the pump device 1 shown in FIG. 1 cut along a plane including a rotation axis L. As shown in FIGS. 1 and 2, the pump device 1 has a case 2 having a suction pipe 21 and a discharge pipe 22 extending to one axial side L1, a motor 10 disposed on the other axial side L2 of the case 2, and an impeller 25 disposed in a pump chamber 20 inside the case 2. The impeller 25 is driven to rotate around the rotation axis L by the motor 10. In the pump device 1 of this embodiment, the fluid flowing through the pump chamber 20 is a liquid. The pump device 1 is used under conditions in which, for example, the environmental temperature and the fluid temperature are likely to change.

[0026] The motor 10 includes an annular stator 3, a rotor 4 arranged inside the stator 3, a support shaft that rotatably supports the rotor 4, and a resin housing 6 that covers the stator 3. The support shaft 5 is made of metal or ceramic. The impeller 25 rotates integrally with the rotor 4. As shown in FIG. 2, in the pump device 1, the impeller 25 and the pump chamber 20 are provided on one side L1 of the stator 3 in the axial direction.

[0027] As shown in Fig. 2, the pump chamber 20 is provided between the case 2 and the housing 6. The case 2 has an upper wall 23 located on one side L1 in the axial direction of the pump chamber 20, and a side wall 29 surrounding the outer periphery of the pump chamber 20 and extending in the circumferential direction. As shown in Fig. 1, the suction pipe 21 extends in the axial direction at the radial center of the case 2. The discharge pipe 22 extends from the side wall 29 in a direction perpendicular to the rotation axis L of the motor 10.

[0028] 2, the stator 3 includes a stator core 31, an insulator 32 overlapping the stator core 31 from one side L1 in the axial direction, an insulator 33 overlapping the stator core 31 from the other side L2 in the axial direction, and a plurality of coils 35 wound around a plurality of salient poles provided on the stator core 31 via the insulators 32 and 33. The motor 10 is a three-phase motor. Thus, the plurality of coils 35 includes a U-phase coil, a V-phase coil, and a W-phase coil.

[0029] The rotor 4 includes a rotor member 40 made of resin. The rotor member 40 extends in the axial direction. The pump stator 3 includes a first cylindrical portion 41 having a first end portion L1 and a flange portion 45 formed at an end portion of one side L1 in the axial direction of the first cylindrical portion 41. The first cylindrical portion 41 extends from the radial inside of the stator 3 towards the pump chamber 20 and opens at the pump chamber 20. A cylindrical drive magnet 8 is held on the outer circumferential surface of the first cylindrical portion 41. The drive magnet 8 faces the stator 3 on the radial inside. The drive magnet 8 is made of, for example, a neodymium bonded magnet.

[0030] The impeller 24 is connected to the flange portion 45 of the rotor member 40 from one side L1 in the axial direction. In this embodiment, the flange portion 45 and the impeller 24 constitute the impeller 25 connected to the first cylindrical portion 41 of the rotor member 40. The impeller 24 includes a disk portion 26 that faces the flange portion 45 in the axial direction, and a plurality of blade portions 261 that protrude from the disk portion 26 to the other side L2 in the axial direction. The impeller 24 is fixed to the flange portion 45 via the blade portions 261. A central hole 260 is formed in the center of the disk portion 26. The disk portion 26 is inclined toward the flange portion 45 as it moves radially outward. The plurality of blade portions 261 are arranged at equal angular intervals. Each blade portion 261 extends radially outward while curving in an arc from the periphery of the central hole 260.

[0031] In the rotor member 40, a cylindrical radial bearing 11 is held on the radial inside of the first cylindrical portion 41. The rotor 4 is rotatably supported on the support shaft 5 via the radial bearing 11. An end portion on the other axial side L2 of the support shaft 5 is held in a shaft hole 65 formed in a bottom wall 63 of the housing 6. The case 2 has three support portions 27 extending from the inner circumferential surface of the suction pipe 21 to the motor 10 side. The support portions 27 are each formed with a tube portion 28 that opens to the other axial side L2, and an end portion on one axial side L1 of the support shaft 5 is held by the tube portion 28.

[0032] An annular thrust bearing 12 is attached to the end of one axial side L1 of the support shaft 5, and the thrust bearing 12 is disposed between the radial bearing 11 and the end face of the cylindrical portion 28. The radial bearing 11 is pressed against the thrust bearing 12 from the other axial side L2 by the magnetic attraction force of the drive magnet 8. Here, at least a part of the end of the other axial side L2 of the support shaft 5 and the shaft hole 65 has a D-shaped cross section. In addition, the end of the one axial side L1 of the support shaft 5 and the hole of the thrust bearing 12 have a D-shaped cross section. Therefore, the support shaft 5 and the thrust bearing 12 are prevented from rotating relative to the housing 6.

[0033] The housing 6 is a resin sealing member 60 that covers the stator 3 from both radial and axial sides. The resin sealing member 60 is made of polyphenylene sulfide (PPS). The stator 3 is integrated with the resin sealing member 60 by insert molding. The housing 6 is a partition member having a first partition portion 61 facing the upper wall 23 that covers one axial side L1 of the pump chamber 20, a second partition portion 62 interposed between the stator 3 and the drive magnet 8, and a bottom wall 63 provided at the end of the second partition portion 62 on the other side L2. The housing 6 also has a cylindrical body portion 66 that covers the stator 3 from the radial outside.

[0034] As shown in Figs. 1 and 2, a cover 18 is fixed to an end portion 64 of the housing 6 on the other axial side L2 from the other axial side L2. As shown in Fig. 2, a board 19 on which a circuit for controlling power supply to the coil 35 is provided is disposed between the cover 18 and the bottom wall 63 of the housing 6. A metal winding terminal 71 protruding from the stator 3 through the bottom wall 63 of the housing 6 to the other axial side L2 is connected to the board 19 by soldering. The housing 6 has a columnar portion 67 protruding from the bottom wall 63 to the other axial side L2. The board 19 is fixed to the columnar portion 67 by a screw.

[0035] As shown in FIG. 1, the housing 6 includes a cylindrical connector housing 69 that extends radially outward from a body portion 66 that surrounds the outer periphery of the stator 3. , and a connector terminal one end of which is connected to the board 19 is disposed. When the connector is connected to the connector housing 69, a drive current generated in a circuit mounted on the board 19 is supplied to each coil 35 via the winding terminal 71. As a result, the rotor 4 rotates about the rotation axis L of the motor 10. This causes the impeller 25 to rotate within the pump chamber 20, creating a negative pressure inside the pump chamber 20, so that the fluid is sucked from the suction pipe 21 into the pump chamber 20 and discharged from the discharge pipe 22.

[0036] (Drive magnet and radial bearing retention structure) FIG. 3 is a side view of the rotor. FIG. 4 is an exploded perspective view of the rotor 4 and the radial bearing 11 as viewed from one side L1 in the axial direction. FIG. 5 is an exploded perspective view of the rotor 4 and the radial bearing 11 as viewed from the other side L2 in the axial direction. FIG. 6 is a sectional perspective view of the rotor member 40. FIG. 7 is a partial sectional view of the rotor 4, the radial bearing 11, and the support shaft 5 cut along a plane including the rotation axis. FIG. 8 and FIG. 9 are sectional perspective views of the rotor 4, the radial bearing 11, and the support shaft 5 cut along a plane perpendicular to the rotation axis L. FIG. 8 is a partial sectional view cut along the AA position in FIG. 7, and FIG. 9 is a partial sectional view cut along the BB position in FIG. 7.

[0037] As shown in FIG. 2 and FIG. 5, the rotor member 40 includes an annular seat portion 42 that protrudes radially outward from the first cylindrical portion 41 at a position spaced from the flange portion 45 toward the other side L2 in the axial direction. The first cylindrical portion 41 includes a magnet holding portion 410 that extends from the seat portion 42 toward the other side L2 in the axial direction. The magnet holding portion 410 fits inside the drive magnet 8 to hold the drive magnet 8. At that time, the seat portion 42 supports an end portion of the drive magnet 8 on one side L1 in the axial direction. As shown in FIG. 2, FIG. 3, and FIG. 7, a crimped portion 43 is formed at an end portion of the other side L2 in the axial direction of the magnet holding portion 410, which overlaps with an end portion of the other side L2 of the drive magnet 8 from the other side L2 in the axial direction. The shape of the rotor member 40 shown in FIG. 4, FIG. 5, and FIG. 7 is a shape before the tip portion 411 on the other side L2 of the magnet holding portion 410 is crushed, and is a shape before the crimped portion 43 is formed.

[0038] 4 and 5, the radial bearing 11 includes a cylindrical portion 110 extending in the axial direction, and a large diameter portion 111 provided at an end portion on one side L1 in the axial direction of the cylindrical portion 110. The rotor member 40 is a resin molded product, and the radial bearing 11 is fixed to the magnet holding portion 410 by insert molding.

[0039] 2 and 7, the drive magnet 8 includes a second cylindrical portion 81 extending in the axial direction, and an annular rib 82 protruding radially inward from an end of the second cylindrical portion 81 on the other axial side L2. The second cylindrical portion 81 and the annular rib 82 are connected to each other so as to form an L-shaped cross-sectional shape as a whole. The rotor member 40 and the drive magnet 8 are assembled such that the magnet holding portion 410 of the rotor member 40 is inserted into the inside of the second cylindrical portion 81 of the drive magnet 8, and the tip portion 411 of the magnet holding portion 410 fits into the inside of the annular rib 82.

[0040] As shown in Figs. 4, 8 and 9, the drive magnet 8 has a plurality of magnet side ribs 83 protruding radially inward from the inner peripheral surface of the second cylindrical portion 81. The magnet side ribs 83 are arranged in the circumferential direction at regular angular intervals. In this embodiment, the magnet side ribs 83 are arranged at six locations at 60 degree intervals. As shown in Figs. 4 and 5, the end of the magnet side rib 83 on the other side L2 in the axial direction is connected to the annular rib 82. The magnet holding portion 410 fits inside the six magnet side ribs 83 arranged radially.

[0041] As shown in FIG. 4, the rotor member 40 has a plurality of cutouts 420, which are formed by cutting the outer periphery of the seat portion 42 toward the inner periphery, spaced apart in the circumferential direction. A recess 421 extending in the radial direction is provided at the circumferential center of each cutout 420. , and a first protrusion 422 protruding to the other axial side L2 is provided. The first protrusion 422 is connected to the outer peripheral surface of the magnet holding part 410 and extends to the outer edge of the seat part 42. The axial height of the first protrusion 422 is greater than the axial depth of the recess 421. In this embodiment, the notch 420 and the recess 421 are provided in three locations at intervals of 120 degrees.

[0042] As shown in FIG. 4, the drive magnet 8 has three first recesses 84 and three gate marks 85 alternately provided at equal angular intervals in the circumferential direction on the end face of one axial side L1 of the second cylindrical portion 81. When the drive magnet 8 is fixed to the magnet holding portion 410, the end face of one axial side L1 of the second cylindrical portion 81 is abutted against the seat portion 42 from the other axial side L2. At that time, the multiple first protrusions 422 are fitted into the first recesses 84 (see FIG. 4) formed on the end face of one axial side L1 of the second cylindrical portion 81, respectively, to form a rotation stopper portion E. This prevents the drive magnet 8 from rotating relative to the rotor member 40.

[0043] When the drive magnet 8 is attached to the outer periphery of the magnet holding portion 410, a tip portion 411 (see Figs. 4 and 5) of the other axial side L2 of the magnet holding portion 410 protrudes toward the other axial side L2 beyond an end face of the other axial side L2 of the drive magnet 8. When manufacturing the rotor 4, the crimped portion 43 is formed by crushing the tip portion 411 of the magnet holding portion 410 (see Figs. 3, 7 and 8). The crimped portion 43 overlaps the inner peripheral edge of the annular rib 82 of the drive magnet 8 over the entire circumference from the other axial side L2.

[0044] In this embodiment, the drive magnet 8 has six poles, and the stator 3 has nine slots. Therefore, the outer peripheral surface of the drive magnet 8 is magnetized with three alternating north and south poles. As described above, the drive magnet 8 has magnet side ribs 83 in six locations. The magnet side ribs 83 may be formed, for example, at the location where the magnetic flux density is greatest, that is, at the circumferential center of each magnetic pole.

[0045] (cooling flow path) As shown in FIGS. 2 and 7, in the rotor 4 of this embodiment, a radial gap is provided between the magnet holding portion 410 of the rotor member 40 and the drive magnet 8. This gap functions as a flow channel F through which the fluid in the pump chamber 20 flows. The flow channel F communicates with a gap G1 (see FIG. 2) between the drive magnet 8 and the second partition wall portion 62 of the housing 6 via an inlet 44 (see FIG. 3) provided between the second cylindrical portion 81 of the drive magnet 8 and the seat portion 42 of the rotor member 40. When the fluid in the pump chamber 20 flows through the flow channel F, the drive magnet 8 and the magnet holding portion 410 are cooled, and the radial bearing 11 is cooled via the magnet holding portion 410.

[0046] 3, the inlet 44 is provided between the second cylindrical portion 81 of the drive magnet 8 and the seat portion 42, and opens radially outward. As described above, the seat portion 42 is provided with a recess 421 recessed toward one side L1 in the axial direction, and the inlet 44 is formed by the end face of the one side L1 in the axial direction of the second cylindrical portion 81 and the recess 421. The inlet 44 is provided at one location on each side in the circumferential direction of the rotation stopper portion E where the first protrusion 422 of the rotor member 40 is fitted into the first recess 84 of the drive magnet 8.

[0047] As shown in Fig. 4 and Fig. 5, the rotor member 40 has a plurality of rotor member-side ribs 50 formed on the outer circumferential surface of the magnet holding portion 410 in the first cylindrical portion 41. The rotor member-side ribs 50 extend in the axial direction with a constant width. The rotor member-side ribs 50 have an end on one side L1 in the axial direction connected to the seat portion 42. In this embodiment, the rotor member-side ribs 50 include two types of ribs: a first rib 51 that extends to a tip portion 411 on the other side L2 of the magnet holding portion 410, and a second rib 52 that is shorter in the axial direction than the first rib 51.

[0048] As shown in Figs. 8 and 9, rotor member ribs 50 are provided at six locations at 60 degree intervals on the outer circumferential surface of the magnet holding portion 410. The rotor member 40 and the drive magnet 8 are assembled in such a manner that the angular positions of the rotor member ribs 50 and the magnet side ribs 83 match by engaging the above-mentioned rotation stopper E. The rotor member ribs 50 have a larger circumferential width than the magnet side ribs 83. The gap between the magnet holding portion 410 and the drive magnet 8 is defined in the circumferential direction by the contact between the tip end surface of the rotor member rib 50 and the tip end surface of the magnet side rib 83. This forms a flow path groove F extending in the axial direction.

[0049] 4, 5, 8, and 9, the R1 direction is the front side in the rotation direction of the rotor 4, and the R2 direction is the rear side in the rotation direction of the rotor 4. As shown in Fig. 5, the flow groove F includes a first groove portion F1 extending in the axial direction, a second groove portion F2 extending in the axial direction on the rear side R2 in the rotation direction of the rotor 4 relative to the first groove portion F1, and a third groove portion F3 extending in the circumferential direction and connecting the ends of the first groove portion F1 and the second groove portion F2 on the other side L2 in the axial direction. That is, a part of the flow groove F forms a substantially U-shaped groove that is folded back once in the axial direction.

[0050] 5, the third groove portion F3 extends circumferentially on the other axial side L2 of the second rib 52. The magnet-side rib 83 abutting against the second rib 52 extends toward the other side L2 further than the second rib 52. For this reason, a gap that becomes the third groove portion F3 is formed between the tip of the magnet-side rib 83 abutting against the second rib 52 and the outer circumferential surface of the magnet holding portion 410 (see FIG. 9).

[0051] As shown in FIG. 5, the recess 421 forming the inlet 44 is provided at an angular position that coincides with the first groove F1. Among the first groove F1, the second groove F2, and the third groove F3 that form a U-shaped flow passage as a whole, the third groove F3 and the second groove F2 are provided on the rear side R2 in the rotation direction with respect to the first groove F1 that communicates with the inlet 44 (recess 421). Therefore, when the rotor 4 rotates in the R1 direction, the fluid in the first groove F1 moves in the R2 direction due to inertia force and flows through the third groove F3 and the second groove F2, and a flow in the D direction shown in FIG. 5 occurs. As a result, the first groove F1 becomes negative pressure, and the fluid flows from the inlet 44 into the first groove F1. Therefore, while the rotor 4 rotates, the fluid continues to flow through the flow passage groove F in the D direction shown in FIG. 5.

[0052] The radially outer portion of the second groove F2 in the seat 42 is a flat surface that supports the drive magnet 8, and therefore a wide opening such as the inlet 44 is not formed on the radially outer side of the second groove F2. For this reason, a pressure difference occurs between the inlet and outlet sides of the first groove F1, the second groove F2, and the third groove F3 that form a U-shaped flow passage, making it easy for fluid to flow in.

[0053] As shown in FIG. 8, six flow grooves F are provided between the magnet holding portion 410 and the drive magnet 8, which are partitioned by six rotor member side ribs 50 and magnet side ribs 83 extending in the axial direction. Here, four of the six rotor member side ribs 50 are first ribs 51 extending to the tip of the other side L2 of the magnet holding portion 410, and the other two are second ribs 52 having a shorter axial length than the first ribs 51. The first ribs 51 and the second ribs 52 are alternately arranged in the circumferential direction. Therefore, four of the six flow grooves F form a flow path connected in a U-shape via the third groove portion F3 formed on the other side L2 of the second rib 52 as described above, while the other two form a flow path extending linearly from the seat portion 42 to the annular rib 82.

[0054] (Bearing cooling passage) 6, the first cylindrical portion 41 of the rotor member 40 includes a connection portion 412 that extends in the axial direction between the flange portion 45 and the seat portion 42. The first space H inside the connection portion 412 has one axial side L1 that opens to the center of the flange portion 45 and communicates with the pump chamber 20. The first space H communicates with the pump chamber 20 via a through hole 46 that penetrates the connection portion 412. The through holes 46 are provided at two locations on opposite sides in the radial direction. As shown in FIG. 2, an end of the support shaft 5 extends into the first space H and is inserted into the cylindrical portion 28 disposed in the first space H. A part of the large diameter portion 111 of the radial bearing 11 is disposed in the first space H and abuts against the thrust bearing 12.

[0055] The inner peripheral surface of the connection portion 412 is provided with a flow groove 47 having an arc-shaped cross section extending in the axial direction. Each flow groove 47 communicates with a bearing cooling flow path 48 that penetrates the magnet holding portion 410 in the axial direction. The flow groove 47 and the bearing cooling flow path 48 are provided at two locations on opposite sides in the radial direction. The other end of the bearing cooling flow path 48 in the axial direction communicates with a gap G2 (see FIG. 2) between the bottom wall 63 of the housing 6 and the magnet holding portion 410. Therefore, the fluid in the pump chamber 20 that flows in from the outer periphery side of the through hole 46 and the flange portion 45 side flows through the bearing cooling flow path 48, thereby cooling the radial bearing 11 and the magnet holding portion 410.

[0056] (Main effects of this embodiment) As described above, the pump device 1 of this embodiment includes the motor 10 including the rotor 4 and the stator 3 surrounding the outer periphery of the rotor 4, and the impeller 25 disposed in the pump chamber 20 provided on one side L1 in the axial direction relative to the stator 3 when the direction along the rotation axis L of the rotor 4 is defined as the axial direction, and rotates integrally with the rotor 4. The rotor 4 includes a rotor member 40 including a first cylindrical portion 41 extending in the axial direction, and a drive magnet 8 surrounding the outer periphery of the first cylindrical portion 41, and a radial bearing 11 is held inside the first cylindrical portion 41. The drive magnet 8 includes a second cylindrical portion 81 surrounding the outer periphery of the first cylindrical portion 41 and extending in the axial direction, and an annular rib 82 protruding radially inward from an end of the second cylindrical portion 81 on the other axial side L2. The rotor member 40 includes a seat portion 42 that protrudes radially outward from the first cylindrical portion 41 and supports an end portion of one axial side L1 of the second cylindrical portion 81, and a crimped portion 43 that extends radially outward from the end portion of the other axial side L2 of the first cylindrical portion 41 and overlaps the annular rib 82 from the other axial side L2.

[0057] According to this embodiment, the driving magnet 8 is held between the seat 42 and the crimped portion 43 provided on the first cylindrical portion 41 of the rotor member 40. The driving magnet 8 is provided with an annular rib 82 protruding radially inward at an end portion located on the tip side (the side where the crimped portion 43 is provided) of the first cylindrical portion 41. In this way, by providing the driving magnet 8 with a portion (annular rib 82) protruding toward the inner periphery side instead of making the driving magnet 8 simply cylindrical, it is possible to ensure the volume and the necessary magnetic attraction force even if the axial length is shortened. In addition, since the annular rib 82 is provided at the end portion on the side where the crimped portion 43 is provided, the radial width of the end face that receives the crimped portion 43 is large. Therefore, there is little risk that the crimped portion 43 will protrude radially outward from the driving magnet 8, and therefore it is possible to suppress the deterioration of the shape accuracy of the rotor 4 due to the thermal crimping.

[0058] In this embodiment, there is a radial gap between the first cylindrical portion 41 and the second cylindrical portion 81, and this gap functions as a flow channel F through which the fluid in the pump chamber 20 flows. The other axial side L2 of the flow channel F is blocked by the annular rib 82 and the crimped portion 43. With this configuration, the flow channel F has a depth (diameter) according to the protruding dimension of the annular rib 82, so that the volume of the flow channel F can be secured and a large amount of fluid can flow between the drive magnet 8 and the first cylindrical portion 41. Therefore, the cooling effect of the radial bearing 11 held inside the first cylindrical portion 41 and the cooling effect of the drive magnet 8 can be improved. Therefore, the shortening of the life of the parts and the deterioration of the magnetic properties of the drive magnet 8 due to high temperatures can be suppressed.

[0059] In this embodiment, a plurality of magnet-side ribs 83 that protrude radially inward and extend in the axial direction are arranged in the circumferential direction on the inner peripheral surface of the second cylindrical portion 81, and the gaps between adjacent magnet-side ribs 83 in the circumferential direction function as flow channel grooves F. With this structure, the magnet-side ribs 83 arranged radially Since the first cylindrical portion 41 can be fitted inside the magnet-side ribs 83, a flow channel F with a large volume can be secured, and the drive magnet 8 can be assembled with high precision. In addition, since the second cylindrical portion 81 can be reinforced by the magnet-side ribs 83, the strength of the drive magnet 8 can be increased.

[0060] In this embodiment, the end portion on the other axial side L2 of the magnet-side rib 83 is connected to the annular rib 82. This connects the second cylindrical portion 81 and the annular rib 82 via the magnet-side rib 83, thereby increasing the strength of the drive magnet 8.

[0061] In this embodiment, a plurality of rotor member-side ribs 50 that protrude radially outward and extend in the axial direction are arranged in the circumferential direction on the outer circumferential surface of the first cylindrical portion 41. The tip surfaces of the magnet-side ribs 83 abut against the tip surfaces of the rotor member-side ribs 50 to define flow path grooves F in the circumferential direction. In this manner, by forming ribs not only on the drive magnet 8 but also on the rotor member 40, the depth (radial dimension) of the flow path grooves F can be made larger. Therefore, the volume of the flow path grooves F can be secured.

[0062] In this embodiment, an inlet 44 communicating with the flow path groove F is provided between the seat portion 42 and the second cylindrical portion 81, so that the fluid in the pump chamber 20 can flow into the flow path groove F through the gap G1 on the outer periphery of the drive magnet 8.

[0063] In this embodiment, the flow channel F includes a first groove portion F1 extending in the axial direction, a second groove portion F2 extending in the axial direction on the rear side (R2 direction) of the rotation direction of the rotor 4 relative to the first groove portion F1, and a third groove portion F3 extending in the circumferential direction and connecting the ends of the first groove portion F1 and the second groove portion F2 on the other side L2 in the axial direction. The inlet 44 communicates with the first groove portion F1. That is, the flow channel F in this embodiment has a shape in which the first groove portion F1 and the second groove portion F2 extending in the axial direction are connected to each other in the axial direction by the third groove portion F3 in a shape (U-shape) that is folded back once in the axial direction. This makes it possible to increase the area in contact with the fluid compared to a case in which a flow channel is simply provided in a straight line, thereby improving the cooling effect. In addition, when the rotor 4 rotates, the fluid flows to the rear side (R2 direction) in the rotation direction due to inertia force, so that the inlet 44 side becomes negative pressure and the fluid in the pump chamber 20 continues to flow in. Therefore, the cooling effect can be improved.

[0064] In this embodiment, the seat portion 42 is provided with a recess 421 recessed toward one side L1 in the axial direction, and the inlet 44 is a gap between the bottom surface of the recess 421 and an end face of the one side L1 in the axial direction of the second cylindrical portion 81. Therefore, the inlet 44 that communicates between the outer circumferential side and the inner circumferential side of the drive magnet 8 can be formed with a simple structure without providing a through hole in the part.

[0065] In this embodiment, the first protrusion 422 protruding from the bottom surface of the recess 421 fits into the first recess 84 provided on the end surface of the drive magnet 8, and the portions on both sides of the recess 421 in the circumferential direction of the first protrusion 422 form two inlets 44. In this way, it is possible to provide a rotation stopper E for preventing relative rotation of the drive magnet 8 with respect to the rotor member 40. Also, since the angular position of the inlet 44 with respect to the drive magnet 8 can be adjusted, the inlet 44 can be provided at an appropriate angular position.

[0066] In this embodiment, the impeller 25 includes a flange portion 45 provided at an end of one axial side L1 of the rotor member 40, and an impeller 24 fixed to the flange portion 45 from the one axial side L1. The first cylindrical portion 41 includes a connection portion 412 extending in the axial direction between the flange portion 45 and the seat portion 42, and a magnet holding portion 410 that fits inside the drive magnet 8, and the radial bearing 11 is held inside the magnet holding portion 410. The inside of the connection portion 412 is a first space H through which the fluid of the pump chamber 20 flows via a through hole 46 that penetrates the connection portion 412 in the radial direction, and the first space H is a through hole 46 that penetrates the magnet holding portion 410 in the axial direction. The gap G1 communicates with the bearing cooling passage 48. By providing such a structure, the fluid in the pump chamber 20 can be made to flow into the bearing cooling passage 48 from a position (the center of the flange portion 45) different from the gap G1 on the outer periphery side of the drive magnet 8. This improves the cooling effect.

[0067] (Other forms) The present invention includes the same configuration as the rotor 4 described above, except that no flow channel F is provided between the drive magnet 8 and the magnet holding portion 410. In other words, the present invention includes a configuration in which the outer circumferential surface of the magnet holding portion 410 is in close contact with the inner circumferential surface of the second cylindrical portion 81 of the drive magnet 8, with no gap being formed.

[0068] The present invention can have the following configurations. (1) a motor including a rotor and a stator surrounding an outer periphery of the rotor; an impeller disposed in a pump chamber provided on one side of the stator in the axial direction, the impeller rotating integrally with the rotor, the impeller being defined as an axial direction of the rotor along a rotation axis of the rotor; The rotor includes a rotor member having a first cylindrical portion extending in the axial direction, and a drive magnet surrounding an outer periphery of the first cylindrical portion, and a radial bearing is held inside the first cylindrical portion. the drive magnet includes a second cylindrical portion that surrounds an outer periphery of the first cylindrical portion and extends in the axial direction, and an annular rib that protrudes radially inward from an end portion of the second cylindrical portion on the other side in the axial direction, The pump device is characterized in that the rotor member includes a seat portion that protrudes radially outward from the first cylindrical portion and supports one end of the second cylindrical portion in the axial direction, and a crimped portion that extends radially outward from the other end of the first cylindrical portion in the axial direction and overlaps the annular rib from the other side in the axial direction.

[0069] (2) a radial gap is provided between the first cylindrical portion and the second cylindrical portion, the gap functions as a flow path groove through which fluid in the pump chamber flows; The pump device according to (1) above, wherein the flow passage groove is blocked on the other side in the axial direction by the annular rib.

[0070] (3) A plurality of magnet-side ribs are arranged in a circumferential direction on an inner peripheral surface of the second cylindrical portion, the magnet-side ribs protruding radially inward and extending in the axial direction, The pump device according to (2) above, characterized in that the gaps between the magnet-side ribs adjacent to each other in the circumferential direction function as the flow passage grooves.

[0071] (4) The pump device according to (3) above, wherein the other end of the magnet-side rib in the axial direction is connected to the annular rib.

[0072] (5) A plurality of rotor member-side ribs are arranged in a circumferential direction on an outer circumferential surface of the first cylindrical portion, the rotor member-side ribs protruding radially outward and extending in the axial direction, The pump device according to (3) or (4) above, characterized in that the flow passage grooves are defined in the circumferential direction by the tip surfaces of the ribs on the magnet side abutting against the tip surfaces of the ribs on the rotor member side.

[0073] (6) The pump device according to any one of (2) to (5) above, wherein an inlet communicating with the flow passage groove is provided between the seat portion and the second cylindrical portion.

[0074] (7) the flow passage groove includes a first groove portion extending in the axial direction, a second groove portion extending in the axial direction on a rear side of the first groove portion in a rotational direction of the rotor, and a third groove portion extending in a circumferential direction and connecting ends of the first groove portion and the second groove portion on the other side in the axial direction, The pump device according to (6) above, wherein the inlet is in communication with the first groove portion.

[0075] (8) The seat portion is provided with a recess that is recessed toward one side in the axial direction, The pump device according to (6) or (7) above, wherein the inlet is a gap between a bottom surface of the recess and an end surface on one side in the axial direction of the second cylindrical portion.

[0076] (9) a first protrusion protruding from a bottom surface of the recessed portion is fitted into a first recessed portion provided on an end surface of the drive magnet, thereby forming a rotation stopper for preventing relative rotation of the drive magnet with respect to the rotor member, The pump device according to (8) above, wherein the recess has two circumferentially opposite portions of the first recess that define the inlet ports at two locations adjacent to each other in the circumferential direction in the rotation stopper portion.

[0077] (10) the impeller includes a flange portion provided at one end of the rotor member in the axial direction, and an impeller fixed to the flange portion from one side in the axial direction, the first cylindrical portion includes a connection portion extending in an axial direction between the flange portion and the seat portion, and a magnet holding portion that fits inside the drive magnet, and the radial bearing is held inside the magnet holding portion; The inside of the connection portion is a first space through which fluid of the pump chamber flows via a through hole that radially penetrates the connection portion, The pump device according to any one of (1) to (9) above, wherein the first space is in communication with a bearing cooling passage passing through the magnet holding portion in the axial direction. [Explanation of symbols]

[0078] 1...pump device, 2...case, 3...stator, 4...rotor, 5...support shaft, 6...housing, 8...drive magnet, 10...motor, 11...radial bearing, 12...thrust bearing, 18...cover, 19...substrate, 20...pump chamber, 21...suction pipe, 22...discharge pipe, 23...upper wall, 24...impeller, 25...impeller, 26...disk portion, 27...support portion, 28...tubular portion, 29...side wall, 31...stator core, 32, 33...insulator, 35...coil, 40...rotor member, 41...first cylindrical portion, 42...seat portion, 43...crimping portion, 44...inlet, 45...flange portion, 46...through hole, 47...flow groove, 48...bearing cooling flow path, 50...rotor member side rib, 51...first rib, 52...second rib, 60...resin sealing member, 61...first partition wall portion, 62...second partition wall portion, 63...bottom wall, 64...end portion, 65...shaft hole, 66...body portion, 67...columnar portion, 69...connector housing, 71...winding terminal, 81...cylindrical portion, 82...annular rib, 83...magnet side rib, 84...first recess, 85...gate mark, 110...cylindrical portion, 111...large diameter portion, 260...center hole, 261...wing portion, 410...ma Magnet holding portion, 411...tip portion, 412...connection portion, 420...notch portion, 421...recess portion, 422...first protrusion portion, E...rotation stop portion, F...flow path groove, F1...first groove portion, F2...second groove portion, F3...third groove portion, G1, G2...gap, H...first space, L...rotation axis, L1...one side in the axial direction, L2...the other side in the axial direction, R1...front side in the rotation direction, R2...rotation Rear side of rotation direction

Claims

1. a motor including a rotor and a stator surrounding an outer periphery of the rotor; an impeller disposed in a pump chamber provided on one side of the stator in the axial direction, the impeller rotating integrally with the rotor, the impeller being defined as an axial direction along a rotation axis of the rotor; The rotor includes a rotor member having a first cylindrical portion extending in the axial direction, and a drive magnet surrounding an outer periphery of the first cylindrical portion, and a radial bearing is held inside the first cylindrical portion. the drive magnet includes a second cylindrical portion that surrounds an outer periphery of the first cylindrical portion and extends in the axial direction, and an annular rib that protrudes radially inward from an end portion of the second cylindrical portion on the other side in the axial direction, The rotor member is characterized in that it comprises a seat portion that protrudes radially outward from the first cylindrical portion and supports one end of the second cylindrical portion in the axial direction, and a crimped portion that extends radially outward from the other end of the first cylindrical portion in the axial direction and overlaps the annular rib from the other side in the axial direction.

2. a radial gap is provided between the first cylindrical portion and the second cylindrical portion, the gap functions as a flow path groove through which a fluid in the pump chamber flows; 2. The pump device according to claim 1, wherein the flow passage groove is closed at the other side in the axial direction by the annular rib and the crimped portion.

3. A plurality of magnet-side ribs are arranged in a circumferential direction on an inner peripheral surface of the second cylindrical portion, the magnet-side ribs protruding radially inward and extending in the axial direction, 3. The pump device according to claim 2, wherein a gap between the magnet-side ribs adjacent to each other in the circumferential direction functions as the flow passage groove.

4. 4. The pump device according to claim 3, wherein the other end of the magnet-side rib in the axial direction is connected to the annular rib.

5. A plurality of rotor member-side ribs are arranged in a circumferential direction on an outer circumferential surface of the first cylindrical portion, the rotor member-side ribs protruding radially outward and extending in the axial direction, 4. The pump device according to claim 3, wherein the flow passage grooves are defined in the circumferential direction by abutting a tip surface of the magnet side rib against a tip surface of the rotor member side rib.

6. The pump device according to claim 2 , wherein an inlet port communicating with the flow passage groove is provided between the seat portion and the second cylindrical portion.

7. the flow passage groove includes a first groove portion extending in the axial direction, a second groove portion extending in the axial direction on a rear side of the first groove portion in a rotational direction of the rotor, and a third groove portion extending in a circumferential direction and connecting ends of the first groove portion and the second groove portion on the other side in the axial direction, The pump device according to claim 6 , wherein the inlet is in communication with the first groove portion.

8. The seat portion is provided with a recess that is recessed toward one side in the axial direction, 7. The pump device according to claim 6, wherein the inlet is a gap between a bottom surface of the recess and an end surface on one side in the axial direction of the second cylindrical portion.

9. a first protrusion protruding from a bottom surface of the recessed portion is fitted into a first recessed portion provided on an end surface of the drive magnet; The pump device according to claim 8 , wherein portions of the recess on both sides in a circumferential direction of the first protrusion form the inflow openings at two locations.

10. the impeller includes a flange portion provided at one end of the rotor member in the axial direction, and an impeller fixed to the flange portion from one side in the axial direction, the first cylindrical portion includes a connection portion extending in an axial direction between the flange portion and the seat portion, and a magnet holding portion that fits inside the drive magnet, and the radial bearing is held inside the magnet holding portion; The inside of the connection portion is a first space through which fluid of the pump chamber flows via a through hole that radially penetrates the connection portion, 2. The pump device according to claim 1, wherein the first space communicates with a bearing cooling passage that passes through the magnet holder in the axial direction.

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