Pump device

Abstract

The present invention provides a pump device that can suppress eccentricity between a rotor and a driving magnet and prevent the driving magnet from breaking. In the pump device (1), the rotor (4) has a seat (42) that supports one end (81) of a cylindrical driving magnet and a cylindrical portion (40) that extends from the seat (42) along the rotation center axis (L), and the cylindrical portion (40) is embedded in the inner side of the driving magnet (8). Ribs (46) extending along the rotation center axis (L) are provided at multiple locations in the circumferential direction on the outer peripheral surface of the cylindrical portion (40), and the driving magnet (8) is pressed into the cylindrical portion (40) in a manner that contacts the ribs (46) at multiple locations from the radial outside. Therefore, a gap (G) is formed between the cylindrical portion (40) and the driving magnet (8) between two ribs (46) adjacent in the circumferential direction.

Description

Technical Field

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

[0002] In a pump device, an impeller arranged in a pump chamber is rotated by an electric motor. In the electric motor, the rotor has a cylindrical portion that holds a cylindrical radial bearing on the inside, and a cylindrical driving magnet is fixed to the outer circumference of the cylindrical portion. Here, the rotor and the driving magnet have different thermal expansion coefficients. Therefore, when a sudden temperature change occurs, if a large stress is applied to the driving magnet, the driving magnet may break. Therefore, a structure has been proposed in which a gap is provided between the rotor and the driving magnet, and an elastic seal composed of an adhesive or the like is filled into the gap (see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-246238 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] However, in a structure such as that described in Patent Document 1 in which a gap having an elastic seal is provided between the rotor and the driving magnet, eccentricity may occur between the rotor and the driving magnet. In this case, there is a problem in that the rotation of the rotor is prone to wobble.

[0008] In view of the above problems, an object of the present invention is to provide a pump device capable of suppressing eccentricity between a rotor and a driving magnet while preventing cracking of the driving magnet.

[0009] Technical solutions used to solve technical problems

[0010] In order to solve the above-mentioned problems, the present invention provides a pump device, comprising an electric motor and an impeller arranged in a pump chamber arranged on one side of the rotation center axis relative to the electric motor and connected to the rotor of the electric motor, the rotor being made of resin, and comprising: a seat portion which supports one end portion of a cylindrical driving magnet; and a cylindrical portion which extends from the seat portion along the rotation center axis and is embedded in the inner side of the driving magnet, and ribs extending along the rotation center axis are provided at multiple circumferential positions on the outer peripheral surface of the cylindrical portion, and the driving magnet is pressed into the cylindrical portion in a manner that contacts the ribs from the radial outside.

[0011] In the present invention, a cylindrical portion is provided on the rotor of the electric motor that drives the impeller, into which a driving magnet is embedded. Ribs extending along the axis of rotation are provided at multiple locations in the circumferential direction on the outer peripheral surface of the cylindrical portion. Therefore, when the driving magnet is pressed into the cylindrical portion, eccentricity between the driving magnet and the cylindrical portion can be suppressed. In addition, since the driving magnet and the cylindrical portion are in contact via the ribs, it is difficult to apply large stress to the driving magnet even in the event of a sudden temperature change, thereby suppressing cracking of the driving magnet.

[0012] In the present invention, the seat portion may be provided with recesses at multiple locations along the circumference, and the gap between the cylindrical portion and the driving magnet, formed by two circumferentially adjacent ribs, may be connected to the recesses. This configuration allows the fluid flowing through the pump device to flow through both the recesses in the seat portion and the gap between the cylindrical portion and the driving magnet. This allows the rotor and driving magnet to be cooled, thereby suppressing heat generation in the driving magnet and the like.

[0013] In the present invention, the following method can be employed: rivets that overlap with the driving magnet are provided at multiple circumferential locations on the end portion of the cylindrical portion opposite the seat portion, and at least a portion of the gap is open between two circumferentially adjacent rivets among the multiple rivets. According to this method, even when the driving magnet is fixed by the rivets of the cylindrical portion, the fluid flowing in the recessed portion of the seat portion and the gap between the cylindrical portion and the driving magnet can pass between the rivets, thereby effectively suppressing heat generation of the driving magnet and the like.

[0014] In the present invention, a through-portion can be provided on the cylindrical portion at an angular position overlapping the rib when viewed radially, extending through both sides of the rotational axis. Providing the through-portion in the rotor's cylindrical portion reduces the pressure difference between the two sides of the rotor in the direction of the rotational axis, thereby suppressing rotor vibration in the direction of the rotational axis. Even in this case, if the through-portion is configured to overlap the rib when viewed radially, the rib can prevent the cylindrical portion from becoming excessively thin.

[0015] In the present invention, a mode may be adopted in which the cylindrical portion is provided with a through portion that penetrates both sides of the rotation center axis when viewed from the radial direction.

[0016] In the present invention, the following method can be adopted: a cylindrical radial bearing is maintained on the inner side of the cylindrical portion, and the through portion is provided by a first groove extending along the rotation center axis on the inner circumferential surface of the cylindrical portion, and a second groove extending along the rotation center axis on the outer circumferential surface of the radial bearing and overlapping with the first groove from the radial inside.

[0017] In the present invention, the rotor may be a resin molded product in which the radial bearing is insert-molded.

[0018] In the present invention, a mode may be adopted in which a mark indicating the position of the first groove is marked on one end portion of the radial bearing in the direction of the rotation center axis.

[0019] In the present invention, the first groove may be provided at an angular position overlapping with the rib when viewed from the radial direction.

[0020] Effects of the Invention

[0021] In the present invention, a cylindrical portion is provided on the rotor of the electric motor that drives the impeller, into which a driving magnet is embedded. Ribs extending along the axis of rotation are provided at multiple locations in the circumferential direction on the outer peripheral surface of the cylindrical portion. Therefore, when the driving magnet is pressed into the cylindrical portion, eccentricity between the driving magnet and the cylindrical portion can be suppressed. In addition, since the driving magnet and the cylindrical portion are in contact via the ribs, it is difficult to apply large stress to the driving magnet even in the event of a sudden temperature change, thereby suppressing cracking of the driving magnet. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a perspective view showing one embodiment of a pump device and a motor to which the present invention is applied.

[0023] Figure 2 yes Figure 1 A longitudinal sectional view of the pump device and the motor is shown.

[0024] Figure 3 yes Figure 2 An explanatory diagram of the impeller, etc. shown.

[0025] Figure 4 yes Figure 2 A perspective view of the rotor, etc. shown.

[0026] Figure 5 This means that the driving magnet is fixed to Figure 2 A longitudinal sectional view of the rotor is shown.

[0027] Figure 6 This means that the driving magnet is fixed to Figure 2 A cross-sectional view of the rotor in the illustrated state.

[0028] Figure 7 yes Figure 2 A cross-sectional view of the rotor is shown.

[0029] Figure 8 is viewed from the other side of the rotation center axis Figure 2 A perspective view of the rotor, etc. shown.

[0030] Figure 9 is viewed from the other side of the rotation center axis Figure 2 Bottom view of the rotor etc. shown.

[0031] Figure 10 Viewed from one side of the rotation center axis Figure 2 A top view of the rotor etc. shown.

[0032] Description of Reference Numerals

[0033] 1…Pump device; 2…Casing; 3…Stator; 4…Rotor; 5…Support shaft; 6…Casing; 8…Drive magnet; 10…Motor; 11…Radial bearing; 15…Through portion; 18…Hood; 19…Base plate; 20…Pump chamber; 25…Impeller; 35…Coil; 40…Cylinder; 42…Seat; 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…Riveted portion; G…Gap; L…Center axis of rotation. DETAILED DESCRIPTION

[0034] Hereinafter, an electric motor 10 and a pump device 1 according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the direction of the rotation center axis L refers to the direction in which the rotation center axis L extends, radial directions (radial inside and radial outside) refer to the radial directions centered on the rotation center axis L, and the circumferential direction refers to the direction of rotation centered on the rotation center axis L.

[0035] (Overall structure)

[0036] Figure 1 This is a perspective view showing one embodiment of a pump device 1 and a motor 10 to which the present invention is applied. Figure 2 yes Figure 1 A longitudinal sectional view of the pump device 1 and the electric motor 10 is shown. Figure 3 yes Figure 2 The impeller 25 and the like are shown in FIG. Figure 1 and Figure 2 In the embodiment, the pump device 1 comprises: a housing 2 having a suction port 21a and a discharge port 22a; an electric motor 10 arranged on the other side L2 of the housing 2 in the direction of the rotation center axis L; and an impeller 25 arranged in a pump chamber 20 inside the housing 2, the impeller 25 being rotationally driven around the rotation center axis L by the electric motor 10. The electric motor 10 comprises: a cylindrical stator 3; a rotor 4 arranged inside the stator 3; a resin casing 6 covering 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 ambient temperature or the temperature of the fluid is prone to change.

[0037] The housing 2 defines a wall surface 23 on one side L1 of the pump chamber 20 in the direction of the rotation axis L, and a circumferentially extending sidewall 29. The housing 2 includes a suction pipe 21 extending along the rotation axis L and a discharge pipe 22 extending perpendicularly to the rotation axis L. The suction pipe 21 and the discharge pipe 22 each have a suction port 21a and a discharge port 22a at their ends. The suction pipe 21 is concentrically disposed with respect to the rotation axis L.

[0038] In the electric motor 10 , the stator 3 includes a stator core 31 , insulators 32 and 33 held by the stator core 31 , and a coil 35 wound around the stator core 31 via the insulators 32 and 33 .

[0039] The rotor 4 includes a cylindrical portion 40 extending from a position radially inwardly opposed to the stator 3 along the rotational center axis L toward the pump chamber 20. The cylindrical portion 40 opens into the pump chamber 20. A cylindrical drive magnet 8 is retained on the outer circumferential surface of the cylindrical portion 40 so as to radially inwardly oppose the stator 3. The drive magnet 8 is, for example, a neodymium bond magnet.

[0040] like Figure 2 and Figure 3 As shown, in the rotor 4, a disc-shaped flange 45 is formed at the end of one side L1 of the cylindrical portion 40 in the direction of the rotational axis L. A disc 26 is connected to the flange 45 from one side L1 in the direction of the rotational axis L. A central hole 260 is formed in the center of the disc 26. A plurality of blades 261 are formed at equal angular intervals on the surface of the disc 26 that faces the flange 45. These blades 261 are curved in an arc shape around the central hole 260 and extend radially outward. The disc 26 is fixed to the flange 45 via the blades 261. Thus, the flange 45 and the disc 26 constitute the impeller 25 connected to the cylindrical portion 40 of the rotor 4. In this embodiment, the disc 26 is tilted so that the radial outer side is located closer to the flange 45 than the radial inner side. In this embodiment, grooves 454 are formed in the flange 45 so that the ends of the blades 261 overlap. In addition, a hole 455 is formed in the flange portion 45 at a position overlapping with the groove 454, and a protrusion 265 is formed on the blade portion 261 of the disk 26 to fit into the hole 455. The hole 455 is referred to in the following description. Figure 8 It can be seen that it is a through hole.

[0041] Again in Figure 2In the rotor 4, a cylindrical radial bearing 11 is retained radially inside the cylindrical portion 40, and the rotor 4 is rotatably supported on the support shaft 5 via the radial bearing 11. The end 51 on the other side L2 in the direction of the rotation center axis L of the support shaft 5 is retained in the shaft hole 65 formed on the bottom wall 63 of the housing 6. A receiving portion 280 is formed on the housing 2, and the receiving portion 280 is opposed to the end 52 on the pump chamber 20 side of the support shaft 5 on the pump chamber 20 side to limit the movable range of the support shaft 5 toward the pump chamber 20 side. The housing 2 has three supporting portions 27 extending from the inner circumference of the suction pipe 21 toward the motor 10 side. A cylindrical portion 28 is formed at the end of the supporting portion 27, with the end 52 on the one side L1 in the direction of the rotation center axis L of the support shaft 5 located inside. The receiving portion 280 is formed by the bottom of the cylindrical portion 28 on the one side L1 in the direction of the rotation center axis L. An annular thrust bearing 12 is mounted on the end 52 of the support shaft 5, positioned between the radial bearing 11 and the cylindrical portion 28. The end 51 of the support shaft 5 and at least a portion of the shaft hole 65 are formed to have a D-shaped cross section, while the end 52 of the support shaft 5 and the hole of the thrust bearing 12 are also formed to have a D-shaped cross section. Therefore, the support shaft 5 and the thrust bearing 12 are prevented from rotating.

[0042] The housing 6 is a partition member having a first partition portion 61 opposed to 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. Furthermore, the housing 6 has a cylindrical main body portion 66 that covers the stator 3 from the radial outside. Therefore, the housing 6 is a resin sealing member 60 that covers the stator 3 from both radial sides and both sides in the direction of the rotation center axis L. It is the resin portion used when the stator 3 is insert-molded using polyphenylene sulfide (PPS) or the like.

[0043] A cover 18 is secured to the end 64 of the housing 6 on the other side L2 in the direction of the rotational axis L. A substrate 19 is disposed between the cover 18 and the bottom wall 63 of the housing 6. This substrate 19 includes circuitry for controlling the power supply to the coil 35. The substrate 19 is secured to the housing 6 by screws 92. Metal winding terminals 71, which extend from the stator 3 through the bottom wall 63 of the housing 6 and project toward the other side L2 in the direction of the rotational axis L, and metal connector terminals 75, which are retained by the housing 6, are soldered to the substrate 19. Electronic components constituting the drive circuit are mounted on the substrate 19. Wiring and other components are also formed on the substrate 19.

[0044] A cylindrical connector housing 69 is formed on the housing 6, and the ends 750 of the connector terminals 75 are located inside the connector housing 69. Therefore, when a connector is connected to the connector housing 69 to supply a signal, the signal is transmitted to each coil 35 via the connector terminals 75, the substrate 19, and the winding terminals 71. As a result, the rotor 4 rotates about the rotational axis L. This causes the impeller 25 to rotate within the pump chamber 20, creating a negative pressure inside the pump chamber 20. Consequently, fluid is drawn into the pump chamber 20 through the intake pipe 21 and discharged through the discharge pipe 22.

[0045] (Structure for Fixing the Driving Magnet 8 to the Cylindrical Portion 40 of the Rotor 4, etc.)

[0046] Figure 4 yes Figure 2 A perspective view of the rotor 4 etc. is shown. Figure 5 It means that the driving magnet 8 is fixed on Figure 2 A longitudinal sectional view of the rotor 4 is shown. Figure 6 It means that the driving magnet 8 is fixed on Figure 2 A cross-sectional view of the rotor 4 is shown in FIG. Figure 7 yes Figure 2 A longitudinal section through the rotor 4 is shown. Figure 8 When viewed from the other side L2 of the rotation center axis L Figure 2 A perspective view of the rotor 4 etc. is shown. Figure 9 When viewed from the other side L2 of the rotation center axis L Figure 2 The bottom view of the rotor 4 etc. is shown.

[0047] like Figure 2 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 、 Figure 8 and Figure 9 As shown, in the motor 10, an annular seat portion 42 is formed on the outer circumference of the cylindrical portion 40 of the rotor 4, extending radially outward at a position separated from the flange portion 45 toward the other side L2. The portion of the cylindrical portion 40 beyond the seat portion 42 on the other side L2 serves as a magnet retaining portion 43. The magnet retaining portion 43 is embedded inside the cylindrical drive magnet 8 to retain the drive magnet 8. At this time, the seat portion 42 supports the end portion 81 of the drive magnet 8 on the one side L1.

[0048] A first annular protrusion 441 extending radially inward is formed on the inner circumferential side of the cylindrical portion 40 of the rotor 4 at a position overlapping with the seat portion 442 when viewed from the radial direction, and a second annular protrusion 42 extending radially inward is formed on the other side L2 of the first protrusion 441 .

[0049] In addition, a space is provided between the seat portion 42 and the flange portion 45. Figure 8The through-hole 44 shown in FIG. Through-hole 44 radially extends through cylindrical portion 40. In this embodiment, through-hole 44 is provided at two locations in cylindrical portion 40, angularly offset by 180 degrees. Therefore, when impeller 25 rotates, a portion of the fluid flows from pump chamber 20 into the inner side of cylindrical portion 40 of rotor 4, then flows back into pump chamber 20 through through-hole 44 in cylindrical portion 40 and along bottom wall 24. Consequently, air and other substances mixed in the fluid are discharged from pump chamber 20.

[0050] In the rotor 4 thus constructed, ribs 46 extending along the rotation center axis L are provided at multiple locations in the circumferential direction on the outer peripheral surface of the magnet holding portion 43, and the driving magnet 8 is pressed into the magnet holding portion 43 so as to contact the multiple ribs 46 from the radially outer side. Therefore, a gap G is formed between the magnet holding portion 43 and the driving magnet 8 between two ribs 46 adjacent in the circumferential direction (see FIG. Figure 6 ).

[0051] In addition, a convex portion 421 is formed on the seat portion 42 to be embedded in the concave portion 811 formed at the end portion 81 of the one side L1 of the driving magnet 8. The convex portion 421 defines the circumferential angular position of the driving magnet 8 by being embedded in the concave portion 811, and prevents the driving magnet 8 from rotating. In addition, a concave portion 422 is formed on the seat portion 42 at a position separated in the circumferential direction relative to the convex portion 421, and the concave portion 422 extends from the inner edge to the outer edge of the seat portion 42. When the driving magnet 8 is fixed to the magnet holding portion 43, the concave portion 422 is connected to the gap G sandwiched between two ribs 46 adjacent in the circumferential direction.

[0052] The end portion 47 of the cylindrical portion 40 on the opposite side from the seat portion 42 is provided with rivet portions 471 (see FIG. Figure 9 ), at least a portion of the gap G opens between two circumferentially adjacent rivet portions 471 among the plurality of rivet portions 471.

[0053] In this embodiment, the ribs 46 and recesses 422 are formed at equal angular intervals at six locations along the circumference, and the recesses 811, protrusions 421, and rivets 471 are formed at equal angular intervals at three locations along the circumference. Furthermore, gate marks 812, formed when the drive magnet 8 was molded, are formed at equal angular intervals at three locations along the circumference of the end portion 81 of the drive magnet 8, at locations separated from the recesses 811 along the circumference.

[0054] In the pump device 1 having the motor 10 configured in this manner, when the driving magnet 8 is press-fitted into the cylindrical portion 40 in the motor 10 driving the impeller 25, the driving magnet 8 contacts the ribs 46 formed on the cylindrical portion 40 of the rotor 4 from the radially outer side. This prevents eccentricity between the driving magnet 8 and the cylindrical portion 40. Furthermore, since the driving magnet 8 and the cylindrical portion 40 are in contact via the ribs 46, even when a sudden temperature change occurs, significant stress is less likely to be applied to the driving magnet 8, thereby preventing cracking of the driving magnet 8.

[0055] Furthermore, in the rotor 4, recesses 422 are provided at multiple locations along the circumference of the seat 42 that supports the end 81 of the driving magnet 8. A gap G between the cylindrical portion 40 and the driving magnet 8, sandwiched between two circumferentially adjacent ribs 46, is connected to the recesses 422. Therefore, the fluid flowing through the pump device 1 can flow through the recesses 422 of the seat 42 and the gap G between the cylindrical portion 40 and the driving magnet 8. This allows the rotor 4 and the driving magnet 8 to be cooled, thereby suppressing heat generation by the driving magnet 8 and the like.

[0056] Furthermore, rivets 471 that overlap with the drive magnet 8 are provided at multiple locations along the circumference of the end portion 47 of the cylindrical portion 40 on the side opposite the seat 42. At least a portion of the gap G opens between two circumferentially adjacent rivets 471 among the multiple rivets 471. Therefore, fluid flowing through the recess 422 of the seat 42 and the gap G between the cylindrical portion 40 and the drive magnet 8 can pass between the rivets 471, effectively suppressing heat generation by the drive magnet 8 and the like.

[0057] (Structure of the Through-Portion 15 of the Rotor 45)

[0058] Figure 10 It is viewed from one side L1 in the direction of the rotation center axis L. Figure 2 The top view of the rotor 4 etc. is shown. Figure 4 、 Figure 5 、 Figure 6 、 Figure 7As shown, in the motor 10 and pump device 1, a through-portion 15 is provided between the cylindrical portion 40 of the rotor 4 and the radial bearing 11. The through-portion 15 extends along both sides of the rotation center axis L, formed by a first groove 48 extending along the rotation center axis L on the inner circumference of the cylindrical portion 40 and a second groove 111 extending along the rotation center axis L on the outer circumference of the radial bearing 11. More specifically, the second groove 111 overlaps with the first groove 48 from the radial inside and, together with the first groove 48, forms the through-portion 15. The first groove 48 and the second groove 111 are each semicircular in cross-section. Therefore, the through-portion 15 extends linearly as a circular hole. Here, the second grooves 111 are formed at four circumferential locations at equal angular intervals, while the first grooves 48 are formed at two circumferential locations at equal angular intervals. Therefore, the two first grooves 48 overlap with two of the four second grooves 111 from the radial outside to form the through-portion 15.

[0059] In the cylindrical portion 40, the first groove 48 is provided at an angular position overlapping the rib 46 when viewed from the radial direction. Therefore, by forming the first groove 48, the rib 46 can suppress the cylindrical portion 40 from becoming too thin.

[0060] Here, an annular first protrusion 441 and a second protrusion 442 are formed on the cylindrical portion 40. These annular first and second protrusions 441, 442 extend radially inward and overlap with the step 116 on one side L1 in the direction of the rotational axis L of the radial bearing 11 and the step 117 on the other side L2 in the direction of the rotational axis L. Meanwhile, a first groove 48 is formed along the inner circumferential surface of the cylindrical portion 40. Thus, the first groove 48 extends through the first and second protrusions 441, 442 as a circular hole, but does not reach the inner edges of the first and second protrusions 441, 442. Consequently, the inner edges of the first and second protrusions 441, 442 each form a continuous arc shape.

[0061] Thus, in this embodiment, the provision of the through-portion 15 extending through both sides of the rotor 4's rotational axis L reduces the likelihood of a large pressure difference occurring on either side of the rotor 4 in the direction of the rotational axis L. Consequently, the rotor 4 is less likely to vibrate in the direction of the rotational axis L. The through-portion 15 is formed by radially overlapping the first groove 48 formed on the inner circumferential surface of the cylindrical portion 40 and the second groove 111 formed on the outer circumferential surface of the radial bearing 111. Therefore, even when the through-portion 15 is formed with a sufficient opening area, the opening area of ​​the first groove 48 can be relatively narrow. Consequently, the strength of the cylindrical portion 40 is less likely to be reduced by the first groove 48, eliminating the need to increase the outer diameter of the cylindrical portion 40.

[0062] Furthermore, the first groove 48 and the second groove 111 extend linearly. Therefore, the rotor 4 can be configured as a resin molded article in which the radial bearing 11 is insert-molded. More specifically, during insert molding, a pin with a circular cross-section is placed in the second groove 111 of the radial bearing 11 within a mold, and after insert molding, the pin is removed to form the through-portion 15, and the rotor 4 is manufactured by insert molding.

[0063] Furthermore, a groove-shaped mark 119 indicating the position of the second groove 111 is marked on the end 118 on one side L1 in the direction of the rotation center axis L of the radial bearing 111. Therefore, during insert molding, the pin placement and the like can be determined based on the mark 119 marked on the end 118 of the radial bearing 11.

[0064] [Other embodiments]

[0065] In the above embodiment, the housing 6 is a resin sealing member 60 that covers the stator 3 from both radial sides and both sides in the direction of the rotation center axis L. However, the present invention can also be applied to a case where the housing 6 is a member that covers only the radial inner side of the stator 3 and the other side L2 in the direction of the rotation center axis L. Furthermore, the present invention can also be applied to a case where only the through portion is provided in the cylindrical portion 40.

Claims

1. A pump device, characterized in that: The pump comprises an electric motor and an impeller which is arranged in a pump chamber provided on one side of a rotation center axis relative to the electric motor and connected to a rotor of the electric motor. The rotor is made of resin. The rotor includes: a seat portion supporting one end of a cylindrical driving magnet; and a cylindrical portion extending from the seat portion along the rotation center axis and embedded in the inner side of the driving magnet. Ribs extending along the rotation center axis are provided at multiple locations in the circumferential direction on the outer peripheral surface of the cylindrical portion. The driving magnet is pressed into the cylindrical portion so as to contact the rib from the radially outer side of the rib. On the seat, recesses are provided at multiple locations along the circumference. A gap between the cylindrical portion and the driving magnet, which is sandwiched between two ribs adjacent to each other in the circumferential direction, is connected to the recessed portion. At the end of the cylindrical portion on the opposite side from the seat portion, rivet portions overlapping with the driving magnet are provided at a plurality of locations in the circumferential direction. At least a portion of the gap opens between two circumferentially adjacent caulking portions among the plurality of caulking portions.

2. The pump device according to claim 1, characterized in that The cylindrical portion is provided with a through portion that penetrates both sides of the rotation center axis at an angular position overlapping with the rib when viewed from the radial direction.

3. A pump device, characterized in that: The pump comprises an electric motor and an impeller which is arranged in a pump chamber provided on one side of a rotation center axis relative to the electric motor and connected to a rotor of the electric motor. The rotor is made of resin. The rotor includes: a seat portion supporting one end of a cylindrical driving magnet; and a cylindrical portion extending from the seat portion along the rotation center axis and embedded in the inner side of the driving magnet. Ribs extending along the rotation center axis are provided at multiple locations in the circumferential direction on the outer peripheral surface of the cylindrical portion. The driving magnet is pressed into the cylindrical portion so as to contact the rib from the radially outer side of the rib. The cylindrical portion is provided with a through portion that penetrates both sides of the rotation center axis when viewed from the radial direction. On the cylindrical portion, a cylindrical radial bearing is held inside. The through portion is provided by a first groove extending along the rotation center axis on the inner peripheral surface of the cylindrical portion and a second groove extending along the rotation center axis on the outer peripheral surface of the radial bearing and overlapping with the first groove from the radial inside.

4. The pump device according to claim 3, characterized in that The rotor is a resin molded product in which the radial bearing is insert-molded.

5. The pump device according to claim 4, characterized in that A mark indicating the position of the first groove is marked on one end portion of the radial bearing in the direction of the rotation center axis.

6. The pump device according to claim 3, characterized in that The first groove is provided at an angular position overlapping with the rib when viewed from the radial direction.

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