Pump equipment

Abstract

To provide a pump device capable of preventing a drive magnet from being cracked while suppressing decentration of a rotor and the drive magnet.SOLUTION: In a pump device 1, a rotor 4 comprises: a seat part 42 supporting one end 81 of a cylindrical drive magnet 8; and a cylindrical part 40 extending from the seat part 42 along a rotation center axial line L. The cylindrical part 40 is fitted inside of the drive magnet 8. Ribs 46 extending along the rotation center axial line L are provided at a plurality of positions in a circumferential direction on an outer peripheral surface of the cylindrical part 40, and the drive magnet 8 is press-fitted into the cylindrical part 40 so as to be in contact with the ribs 46 at the plurality of positions from the outside in a radial direction. Therefore, a space between two ribs 46 which are adjacent to each other in the circumferential direction between the cylindrical part 40 and the drive magnet 8 becomes a gap G.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a pump device in which an impeller is rotated by a motor. [Background technology]

[0002] In a pump device, a motor rotates an impeller located in a pump chamber. The rotor of the motor has 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. Because the rotor and drive magnet have different thermal expansion coefficients, there is a risk that the drive magnet will crack if a large stress is applied to it during a sudden temperature change. To address this issue, a structure has been proposed in which a gap is provided between the rotor and drive magnet, and an elastic sealant such as an adhesive is filled in the gap (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-246238 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a structure such as that described in Patent Document 1, in which a gap is provided between the rotor and the drive magnet to place an elastic sealing material, eccentricity can occur between the rotor and the drive magnet, which can cause the rotor to easily vibrate in rotation.

[0005] In view of the above problems, an object of the present invention is to provide a pump device that can prevent cracking of the drive magnet while suppressing eccentricity between the rotor and the drive magnet. [Means for solving the problem]

[0006] In order to solve the above problems, the pump device of the present invention comprises a motor, an impeller arranged in a pump chamber provided on one side of the rotational axis of the motor and connected to the rotor of the motor, the rotor being made of resin, the rotor comprising a seat portion supporting one end of a cylindrical drive magnet, and a cylindrical portion extending from the seat portion along the rotational axis and fitted inside the drive magnet, the outer surface of the cylindrical portion being provided with ribs extending along the rotational axis at multiple locations in the circumferential direction, and the drive magnet being pressed into the cylindrical portion so as to contact the ribs from the radial outside.

[0007] In the present invention, the rotor of the motor that drives the impeller is provided with a cylindrical portion that fits inside the drive magnet, and the outer peripheral surface of the cylindrical portion is provided with ribs extending along the central axis of rotation at multiple locations in the circumferential direction. Therefore, when the drive magnet is press-fitted into the cylindrical portion, eccentricity between the drive magnet and the cylindrical portion can be suppressed. Furthermore, because the drive magnet and the cylindrical portion are in contact with each other via the ribs, large stress is unlikely to be applied to the drive magnet even when a sudden temperature change occurs, and cracking of the drive magnet can be suppressed.

[0008] In the present invention, an embodiment can be adopted in which recesses are provided in the seat at a plurality of positions in the circumferential direction, and a gap between the cylindrical portion and the drive magnet, sandwiched between two adjacent ribs in the circumferential direction, is connected to the recesses. According to this embodiment, the fluid flowing through the pump device flows through the recesses in the seat and the gap between the cylindrical portion and the drive magnet. Therefore, the rotor and the drive magnet can be cooled, and heat generation by the drive magnet and the like can be suppressed.

[0009] In the present invention, an embodiment can be adopted in which crimped portions that overlap the drive magnet are provided at multiple locations in the circumferential direction on the end of the cylindrical portion opposite the seat portion, and at least a portion of the gap is open between two circumferentially adjacent crimped portions among the multiple crimped portions. According to this embodiment, even when the drive magnet is fixed by the crimped portions of the cylindrical portion, fluid flowing through the recess of the seat portion and the gap between the cylindrical portion and the drive magnet can pass between the crimped portions, thereby efficiently suppressing heat generation from the drive magnet, etc.

[0010] In the present invention, a configuration can be adopted in which the cylindrical portion is provided with through-holes that penetrate both sides of the rotational axis at angular positions that overlap the ribs when viewed from the radial direction. By providing through-holes in the cylindrical portion of the rotor, the pressure difference on both sides of the rotor in the rotational axis direction can be reduced, thereby suppressing vibration in the rotational axis direction of the rotor. Even in this case, if the through-holes are configured to overlap the ribs when viewed from the radial direction, the ribs can prevent the cylindrical portion from becoming too thin. [Effects of the Invention]

[0011] In the present invention, the rotor of the motor that drives the impeller is provided with a cylindrical portion that fits inside the drive magnet, and the outer peripheral surface of the cylindrical portion is provided with ribs extending along the central axis of rotation at multiple locations in the circumferential direction. Therefore, when the drive magnet is press-fitted into the cylindrical portion, eccentricity between the drive magnet and the cylindrical portion can be suppressed. Furthermore, because the drive magnet and the cylindrical portion are in contact with each other via the ribs, large stress is unlikely to be applied to the drive magnet even when a sudden temperature change occurs, and cracking of the drive magnet can be suppressed. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view showing an embodiment of a pump device and a motor to which the present invention is applied; [Figure 2] FIG. 2 is a longitudinal cross-sectional view of the pump device and motor shown in FIG. 1. [Figure 3] FIG. 3 is an explanatory diagram of the impeller and other components shown in FIG. 2. [Figure 4] FIG. 3 is a perspective view of the rotor and other components shown in FIG. 2. [Figure 5] FIG. 3 is a longitudinal cross-sectional view showing a state in which a drive magnet is fixed to the rotor shown in FIG. 2. [Figure 6] FIG. 3 is a cross-sectional view showing a state in which a drive magnet is fixed to the rotor shown in FIG. 2. [Figure 7] FIG. 3 is a cross-sectional view of the rotor shown in FIG. 2. [Figure 8] 3 is a perspective view of the rotor and other components shown in FIG. 2 as viewed from the other side in the direction of the central axis of rotation. [Figure 9] 3 is a bottom view of the rotor and the like shown in FIG. 2 as viewed from the other side in the direction of the central axis of rotation. [Figure 10] 3 is a plan view of the rotor and other components shown in FIG. 2 as viewed from one side in the direction of the central axis of rotation. DETAILED DESCRIPTION OF THE INVENTION

[0013] A motor 10 and a pump device 1 according to an embodiment of the present invention will be described below with reference to the drawings. In the following description, the direction of the central axis of rotation L means the direction in which the central axis of rotation L extends, the radial direction on the radially inner side and the radially outer side means the radial direction centered on the central axis of rotation L, and the circumferential direction means the direction of rotation centered on the central axis of rotation L.

[0014] (Overall composition) FIG. 1 is a perspective view showing one embodiment of a pump device 1 and a motor 10 to which the present invention is applied. FIG. 2 is a vertical cross-sectional view of the pump device 1 and the motor 10 shown in FIG. 1. FIG. 3 is an explanatory diagram of an impeller 25 and the like shown in FIG. 2. In FIGS. 1 and 2, the pump device 1 comprises a case 2 having an intake port 21a and a discharge port 22a, and a rotor 21a extending in the direction of a rotational center axis L relative to the case 2. The pump device 1 has a motor 10 disposed on the other side L2 and an impeller 25 disposed in a pump chamber 20 inside the case 2, and the impeller 25 is driven to rotate about a central rotation axis L by the motor 10. The motor 10 includes a cylindrical stator 3, a rotor 4 disposed inside the stator 3, a resin housing 6 that covers the stator 3, and a round rod-shaped support shaft 5 that rotatably supports the rotor 4. The support shaft 5 is made of metal or ceramic. In the pump device 1 of this embodiment, the fluid is a liquid, and the pump device 1 is used under conditions where the environmental temperature and fluid temperature are prone to change.

[0015] The case 2 forms a wall surface 23 on one side L1 of the pump chamber 20 in the direction of the rotation axis L, and a side wall 29 extending in the circumferential direction. The case 2 is provided with a suction pipe 21 extending along the rotation axis L and a discharge pipe 22 extending in a direction perpendicular to the rotation axis L, and the suction pipe 21 and the discharge pipe 22 are provided with a suction port 21a and a discharge port 22a at their ends, respectively. The suction pipe 21 is provided concentrically with the rotation axis L.

[0016] In the motor 10, the stator 3 has a stator core 31, insulators 32 and 33 held by the stator core 31, and a coil 35 wound around the stator core 31 with the insulators 32 and 33 interposed therebetween.

[0017] The rotor 4 has a cylindrical portion 40 that extends from a position facing the stator 3 on the inside in the radial direction toward the pump chamber 20 along the central axis of rotation L, and the cylindrical portion 40 is open to the pump chamber 20. A cylindrical drive magnet 8 is held on the outer circumferential surface of the cylindrical portion 40 so as to face the stator 3 on the inside in the radial direction. The drive magnet 8 is, for example, a neodymium bonded magnet.

[0018] As shown in FIGS. 2 and 3 , in the rotor 4, a disk-shaped flange portion 45 is formed at the end of one side L1 of the cylindrical portion 40 in the direction of the rotational center axis L, and a disk 26 is connected to the flange portion 45 from the one side L1 in the direction of the rotational center axis L. A central hole 260 is formed in the center of the disk 26. A plurality of blade portions 261 are formed at equal angular intervals on the surface of the disk 26 facing the flange portion 45, and extend radially outward while curving in an arc from the periphery of the central hole 260. The disk 26 is fixed to the flange portion 45 via the blade portions 261. Therefore, the flange portion 45 and the disk 26 form an impeller 25 connected to the cylindrical portion 40 of the rotor 4. In this embodiment, the disk 26 is inclined so that the radially outer side is located closer to the flange portion 45 than the radially inner side. In this embodiment, a groove 454 is formed in the flange portion 45, and the ends of the blade portions 261 overlap with each other. Furthermore, holes 455 are formed in flange portion 45 at positions overlapping grooves 454, and protrusions 265 that fit into holes 455 are formed in blade portions 261 of disk 26. Holes 455 are through-holes, as can be seen from Fig. 8, which will be referred to in the description below.

[0019] 2 again, in the rotor 4, a cylindrical radial bearing 11 is held radially inside the cylindrical portion 40, and the rotor 4 is rotatably supported by the support shaft 5 via the radial bearing 11. An end portion 51 on the other side L2 of the support shaft 5 in the direction of the rotational axis L is held in a shaft hole 65 formed in a bottom wall 63 of the housing 6. In the case 2, a receiving portion 280 is formed opposite the end portion 52 of the support shaft 5 on the pump chamber 20 side, on the pump chamber 20 side, to limit the movable range of the support shaft 5 toward the pump chamber 20. The case 2 is provided with three support portions 27 extending from the inner circumferential surface of the suction pipe 21 toward the motor 10. A tubular portion 28 is formed at the end of the support portion 27, with the end portion 52 on one side L1 of the rotational axis L of the support shaft 5 located inside, and the receiving portion 280 is formed by the bottom portion of the tubular portion 28 on one side L1 in the direction of the rotational axis L. An annular thrust bearing 12 is attached to the end 52 of the support shaft 5, and the thrust bearing 12 is located between the radial bearing 11 and the cylindrical portion 28. At least a part of the end 51 of the support shaft 5 and the shaft hole 65 is formed to have a D-shaped cross section, and the end 52 of the support shaft 5 and the hole of the thrust bearing 12 are formed to have a D-shaped cross section. The surface is formed in a D-shape, so that the support shaft 5 and the thrust bearing 12 are prevented from rotating.

[0020] The housing 6 is a partition member having a first partition portion 61 facing the wall surface 23 of the pump chamber 20 and a second partition portion 62 interposed between the stator 3 and the drive magnet 8. The housing 6 also has a cylindrical body portion 66 that covers the stator 3 from the outside in the radial direction. Therefore, the housing 6 is a resin sealing member 60 that covers the stator 3 from both sides in the radial direction and both sides in the direction of the central axis of rotation L, and is a resin portion that is formed when the stator 3 is insert-molded using polyphenylene sulfide (PPS) or the like.

[0021] A cover 18 is fixed to an end portion 64 of the housing 6 on the other side L2 in the direction of the rotational axis L, and a circuit board 19, on which a circuit for controlling power supply to the coil 35 and the like is provided, is disposed between the cover 18 and the bottom wall 63 of the housing 6. The circuit board 19 is fixed to the housing 6 with screws 92. Metal winding terminals 71, which penetrate the bottom wall 63 of the housing 6 from the stator 3 and protrude to the other side L2 in the direction of the rotational axis L, and metal connector terminals 75 held by the housing 6 are connected to the circuit board 19 by solder. Electronic components constituting a drive circuit are mounted on the circuit board 19. Wiring and the like are also formed on the circuit board 19.

[0022] A cylindrical connector housing 69 is formed in the housing 6, and an end 750 of a connector terminal 75 is located inside the connector housing 69. Therefore, when a connector is connected to the connector housing 69 and a signal or the like is supplied, the signal is supplied to each coil 35 via the connector terminal 75, the circuit board 19, and the winding terminal 71. As a result, the rotor 4 rotates about the central axis of rotation L. This causes the impeller 25 to rotate within the pump chamber 20, creating a negative pressure inside the pump chamber 20. As a result, fluid is sucked into the pump chamber 20 from the suction pipe 21 and discharged from the discharge pipe 22.

[0023] (Fixing structure of drive magnet 8 to cylindrical portion 40 of rotor 4, etc.) FIG. 4 is a perspective view of the rotor 4 etc. shown in FIG. 2. FIG. 5 is a longitudinal sectional view showing the state in which the drive magnet 8 is fixed to the rotor 4 shown in FIG. 2. FIG. 6 is a transverse sectional view showing the state in which the drive magnet 8 is fixed to the rotor 4 shown in FIG. 2. FIG. 7 is a longitudinal sectional view of the rotor 4 shown in FIG. 2. FIG. 8 is a perspective view of the rotor 4 etc. shown in FIG. 2 as seen from the other side L2 in the direction of the rotational center axis L. FIG. 9 is a bottom view of the rotor 4 etc. shown in FIG. 2 as seen from the other side L2 in the direction of the rotational center axis L.

[0024] 2, 4, 5, 6, 7, 8, and 9, in the motor 10, an annular seat 42 is formed on the outer periphery of the cylindrical portion 40 of the rotor 4, protruding radially outward at a position spaced from the flange portion 45 toward the other side L2, and the portion of the cylindrical portion 40 from the seat 42 toward the other side L2 serves as a magnet holding portion 43. The magnet holding portion 43 fits inside the cylindrical drive magnet 8 to hold the drive magnet 8. In this case, the seat 42 supports an end 81 of the drive magnet 8 on one side L1.

[0025] On the inner peripheral side of the cylindrical portion 40 of the rotor 4, a first annular convex portion 441 is formed which protrudes radially inward at a position which overlaps with the seat portion 42 when viewed from the radial direction, and on the other side L2 of the first convex portion 441, a second annular convex portion 442 is formed which protrudes radially inward.

[0026] 8 is provided between the seat portion 42 and the flange portion 45. The through-hole 44 penetrates the cylindrical portion 40 in the radial direction. In this embodiment, the through-hole 44 is provided at two positions in the cylindrical portion 40 that are angularly offset by 180 degrees from each other. When the impeller 25 rotates, part of the fluid flows from the pump chamber 20 into the inside of the cylindrical portion 40 of the rotor 4, and then passes through the through-holes 44 of the cylindrical portion 40 and flows along the bottom wall 24 back into the pump chamber 20. As a result, air and other substances mixed in the fluid are discharged from the pump chamber 20.

[0027] In the rotor 4 configured in this manner, ribs 46 extending along the central axis of rotation L are provided at multiple locations in the circumferential direction on the outer peripheral surface of the magnet holding portion 43, and the drive magnet 8 is press-fitted into the magnet holding portion 43 so as to contact the multiple ribs 46 from the outside in the radial direction. Therefore, between the magnet holding portion 43 and the drive magnet 8, a gap G (see FIG. 6) is formed between two ribs 46 adjacent to each other in the circumferential direction.

[0028] The seat 42 is also formed with a protrusion 421 that fits into a recess 811 formed in the end 81 of one side L1 of the drive magnet 8. By fitting into the recess 811, the protrusion 421 determines the angular position of the drive magnet 8 in the circumferential direction and prevents rotation of the drive magnet 8. The seat 42 is also formed with a recess 422 at a position circumferentially spaced apart from the protrusion 421, and the recess 422 extends from the inner edge to the outer edge of the seat 42. When the drive magnet 8 is fixed to the magnet holder 43, the recess 422 is connected to a gap G sandwiched between two circumferentially adjacent ribs 46.

[0029] At the end 47 of the cylindrical portion 40 opposite the seat portion 42, crimped portions 471 (see Figure 9) that overlap the drive magnet 8 are provided at multiple locations in the circumferential direction, and at least a portion of the gap G is open between two crimped portions 471 that are adjacent to each other in the circumferential direction among the multiple crimped portions 471.

[0030] In this embodiment, ribs 46 and recesses 422 are formed at six circumferential positions at equal angular intervals, while recesses 811, protrusions 421, and crimped portions 471 are formed at three circumferential positions at equal angular intervals. Note that gate marks 812, which were formed when driving magnet 8 was molded, are formed at three circumferential positions at equal angular intervals at positions circumferentially spaced from recesses 811 at end 81 of driving magnet 8.

[0031] In the pump device 1 equipped with the motor 10 configured in this manner, when the drive magnet 8 is press-fitted into the cylindrical portion 40 of the motor 10 that drives the impeller 25, the drive magnet 8 abuts against the ribs 46 formed on the cylindrical portion 40 of the rotor 4 from the radially outer side. This makes it possible to suppress eccentricity between the drive magnet 8 and the cylindrical portion 40. Furthermore, because the drive magnet 8 and the cylindrical portion 40 are in contact with each other via the ribs 46, large stress is unlikely to be applied to the drive magnet 8 even when a sudden temperature change occurs, so cracking of the drive magnet 8 can be suppressed.

[0032] Furthermore, recesses 422 are provided at multiple locations in the circumferential direction in the seat portion 42 that supports the end portion 81 of the drive magnet 8 in the rotor 4, and a gap G formed between two circumferentially adjacent ribs 46 between the cylindrical portion 40 and the drive magnet 8 is connected to the recesses 422. Therefore, the fluid flowing through the pump device 1 can flow through the recesses 422 in the seat portion 42 and the gap G between the cylindrical portion 40 and the drive magnet 8. This allows the rotor 4 and drive magnet 8 to be cooled, thereby suppressing heat generation from the drive magnet 8, etc.

[0033] Furthermore, crimped portions 471 that overlap the drive magnet 8 are provided at multiple locations in the circumferential direction on the end 47 of the cylindrical portion 40 opposite the seat portion 42, and at least a portion of the gap G is open between two crimped portions 471 that are adjacent in the circumferential direction among the multiple crimped portions 471. Therefore, the fluid that flows through the recess 422 of the seat portion 42 and the gap G between the cylindrical portion 40 and the drive magnet 8 can pass between the crimped portions 471, so heat generated by the drive magnet 8, etc., can be effectively dissipated. It can be effectively suppressed.

[0034] (Structure of the through-hole 15 of the rotor 45) FIG. 10 is a plan view of the rotor 4 and other components shown in FIG. 2 as viewed from one side L1 in the direction of the rotational axis L. As shown in FIGS. 4, 5, 6, and 7, in the motor 10 and pump device 1, a through-hole 15 is provided between the cylindrical portion 40 of the rotor 4 and the radial bearing 11. The through-hole 15 penetrates both sides of the rotational axis L. The through-hole 15 is formed by a first groove 48 extending along the rotational axis L on the inner circumferential surface of the cylindrical portion 40 and a second groove 111 extending along the rotational axis L on the outer circumferential surface of the radial bearing 11. More specifically, the second groove 111 overlaps the first groove 48 from the radially inner side and, together with the first groove 48, forms the through-hole 15. The first groove 48 and the second groove 111 each have a semicircular cross section. Therefore, the through-hole 15 extends linearly as a circular hole. Here, the second grooves 111 are formed at four positions in the circumferential direction at equal angular intervals, and the first grooves 48 are formed at two positions in the circumferential direction at equal angular intervals. Therefore, the two first grooves 48 overlap two of the four second grooves 111 from the radial outside to form the through-portions 15.

[0035] In the cylindrical portion 40, the first grooves 48 are provided at angular positions that overlap with the ribs 46 when viewed from the radial direction. Therefore, the formation of the first grooves 48 can prevent the wall thickness of the cylindrical portion 40 from becoming too thin, by the ribs 46.

[0036] Here, the cylindrical portion 40 is formed with annular first and second protrusions 441 and 442 that protrude radially inward and overlap with a step 116 on one side L1 of the radial bearing 11 in the direction of the rotational center axis L and a step 117 on the other side L2 in the direction of the rotational center axis L. Meanwhile, the first groove 48 is formed along the inner circumferential surface of the cylindrical portion 40. Therefore, the first groove 48 penetrates the first and second protrusions 441 and 442 as a circular hole, but does not reach the inner edges of the first and second protrusions 441 and 442. Therefore, the inner edges of the first and second protrusions 441 and 442 each have a continuous arc shape.

[0037] As described above, in this embodiment, the through-holes 15 are provided to penetrate both sides of the rotational axis L of the rotor 4, so a large pressure difference is unlikely to occur on both sides of the rotational axis L with respect to the rotor 4. Therefore, the rotor 4 is unlikely to vibrate in the direction of the rotational axis L. Here, the through-holes 15 are formed by the first grooves 48 formed on the inner peripheral surface of the cylindrical portion 40 and the second grooves 111 formed on the outer peripheral surface of the radial bearing 11 overlapping in the radial direction. Therefore, even when the through-holes 15 are formed with a sufficient opening area, the opening area of ​​the first grooves 48 can be small. Therefore, the strength of the cylindrical portion 40 is unlikely to be reduced by the first grooves 48, so there is no need to increase the outer diameter of the cylindrical portion 40.

[0038] Furthermore, the first groove 48 and the second groove 111 extend linearly. Therefore, the rotor 4 can be configured as a resin molded product in which the radial bearing 11 is insert-molded. More specifically, when performing insert molding, a pin with a circular cross section is placed in the second groove 111 of the radial bearing 11 inside a mold and insert-molded, and then the pin is removed, allowing the rotor 4 to be manufactured by insert molding while forming the through-hole 15.

[0039] Furthermore, a groove-shaped mark 119 indicating the position of the second groove 111 is provided on an end 118 on one side L1 in the direction of the rotation center axis L of the radial bearing 11. Therefore, during insert molding, pin placement and the like can be performed using the mark 119 provided on the end 118 of the radial bearing 11 as a reference.

[0040] [Other embodiments] In the above embodiment, the housing 6 is the resin sealing member 60 that covers the stator 3 from both sides in the radial direction and both sides in the direction of the central axis of rotation L. The present invention may be applied to a member that covers only the inside and the other side L2 in the direction of the rotation center axis L. The present invention may also be applied to a case where a through-hole is provided only in the cylindrical portion 40. [Explanation of symbols]

[0041] 1...pump device, 2...case, 3...stator, 4...rotor, 5...support shaft, 6...housing, 8...drive magnet, 10...motor, 11...radial bearing, 15...penetration portion, 18...cover, 19...substrate, 20...pump chamber, 25...impeller, 35...coil, 40...cylindrical portion, 42...seat portion, 43...magnet holding portion, 45...flange portion, 46...rib, 48...first groove, 60...resin sealing member, 65...shaft hole, 111...second groove, 119...mark, 261...blade portion, 471...crimped portion, G...gap, L...rotational center axis

Claims

1. a motor; and an impeller disposed in a pump chamber provided on one side of a rotational center axis of the motor and connected to a rotor of the motor, the rotor is made of resin, the rotor includes a seat portion that supports one end of a cylindrical drive magnet, and a cylindrical portion that extends from the seat portion along the rotational central axis and is fitted inside the drive magnet, ribs extending along the rotational center axis are provided at a plurality of positions in the circumferential direction on the outer peripheral surface of the cylindrical portion, the drive magnet is press-fitted into the cylindrical portion so as to contact the rib from the outside in the radial direction, The seat portion is provided with recesses at a plurality of positions in the circumferential direction, a gap sandwiched between two adjacent ribs in the circumferential direction between the cylindrical portion and the drive magnet is connected to the outside in the radial direction of the rotor via the recess, When a fluid flows into the pump chamber, the fluid flows from the recess into the gap.

2. 2. The pump device according to claim 1, a plurality of crimped portions that overlap the drive magnet are provided at a circumferential end of the cylindrical portion opposite to the seat portion; The pump device is characterized in that at least a portion of the gap is open between two circumferentially adjacent crimped portions among the plurality of crimped portions.

3. 3. The pump device according to claim 1, the cylindrical portion is provided with a through-portion that passes through both sides of the rotation central axis at an angular position that overlaps with the rib when viewed from a radial direction, The pump device is characterized in that the through portion is a groove provided on the inner circumferential surface of the cylindrical portion.

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