Pump device

Abstract

A pump apparatus suppresses surface pressure between contact surfaces of a thrust bearing and a rotor. A pump device (1) is provided with: a rotor (4) that rotates about a rotation axis in a first rotation direction (CW); a stator (3) disposed around the rotor; an impeller (25) connected to the rotor on one side (L1); a housing (2) that defines a pump chamber (20) that accommodates the impeller; a partition wall (60) which is covered by the housing from one side and divides the pump chamber, and which is disposed between the rotor and the stator; and a thrust bearing (12) which is in contact with a contact surface (410) facing one side of the rotor and supports the rotor in the thrust direction. The rotor is provided with a protrusion (44) protruding radially outward from the outer peripheral surface of the rotor. The protruding part is provided with an inclined surface (441) which faces one side and receives a force that presses the rotor toward the other side (L2) in the axial direction from the fluid in the pump chamber (20) when the rotor rotates in the first rotational direction.

Description

Technical Field

[0001] The invention relates to a pump device. Background Art

[0002] Patent document 1 describes a pump device for circulating a fluid. The pump device of the document includes: a rotor that rotates in a first rotation direction around a rotation axis; a shaft that rotatably supports the rotor; a stator that is disposed around the rotor; an impeller that is connected to one side of the rotor; a first housing that defines a pump chamber that accommodates the impeller; and a friction plate that contacts a contact surface of an upper side portion of the rotor that faces one side, thereby supporting the rotor in a thrust direction. Prior art literature Patent Literature

[0003] Patent Document 1: Japanese Patent Application Publication No. 2017-025905 Summary of the invention

[0004] In a pump device such as Patent Document 1, when the rotor rotates, due to the pressure fluctuation in the pump chamber, a force acts on the rotor to push the rotor toward the side where the pump chamber is located. Therefore, the friction plate always receives surface pressure from the contact surface of the rotor. Here, when the rotation speed of the rotor is increased in order to increase the discharge volume of the pump device, the pressure fluctuation in the pump chamber also increases, so the force pressing the rotor toward one side increases, and the surface pressure received by the friction plate from the contact surface of the rotor increases. Therefore, depending on the use of the pump device, there is a problem that the life of the contact surface between the friction plate and the rotor is easily reduced.

[0005] In view of the above problems, an object of the present invention is to provide a pump device that suppresses the surface pressure of the contact surface between the thrust bearing and the rotor.

[0006] In order to solve the above-mentioned problems, the pump device of the present invention comprises: a rotor, which rotates in a first rotation direction around a rotation axis; a support shaft, which supports the rotor so as to be rotatable; a stator, which is arranged around the rotor; an impeller, which is connected to the rotor on one side of the rotor along the axial direction of the rotation axis; a casing, which divides a pump chamber for accommodating the impeller; a partition wall, which is covered by the casing from the one side to divide the pump chamber and is arranged between the rotor and the stator; and a thrust bearing, which contacts with a contact surface of the rotor facing the one side and supports the rotor in a thrust direction, the rotor having a protrusion protruding radially outward from the outer peripheral surface of the rotor, the protrusion having an inclined surface, the inclined surface facing the one side, and when the rotor rotates in the first rotation direction, the fluid in the pump chamber receives a force that pushes the rotor toward the other side in the axial direction.

[0007] According to the present invention, when the rotor rotates in the first direction, the inclined surface receives the force from the fluid that pushes the rotor toward the other side in the axial direction, thereby reducing the surface pressure between the thrust bearing and the contact surface, thereby preventing the thrust bearing and the contact surface from being shortened in life.

[0008] Furthermore, since the surface pressure between the thrust bearing and the contact surface can be reduced, even when the rotor is rotated at a high speed, an increase in the current flowing through the motor of the pump device can be suppressed, and vibration of the pump device can be suppressed.

[0009] In the present invention, it is preferred that a plurality of protrusions are provided at equal angles in the circumferential direction around the rotation axis. In this way, compared with a case where there is only one protrusion, the force that pushes the rotor to the other side in the axial direction is uniform around the rotation axis. Thus, even when the rotor is pushed to the other side in the axial direction, the rotor can be stably rotated.

[0010] In the present invention, it is preferred that two protrusions are provided in the circumferential direction. Thus, since the two protrusions are 180° apart from each other in the circumferential direction, when the protrusions are formed by resin, it is easy to mold the protrusions.

[0011] In the present invention, the following structure can be adopted: the rotor includes a cylindrical portion and a magnet held on the outside of the cylindrical portion, and the cylindrical portion includes: a first cylindrical portion, which is connected to the impeller; a second cylindrical portion, which is located on the other side of the axial direction of the first cylindrical portion and holds the magnet on the outside; and a seat portion, which protrudes radially outward between the first cylindrical portion and the second cylindrical portion and supports the one side of the magnet, and the protrusion protrudes radially outward from the outer peripheral surface of the first cylindrical portion.

[0012] In the present invention, it is preferred that the protrusion is integrated with the end of the one side of the seat. In this way, the strength of the protrusion can be improved. Thus, even when the inclined surface is subjected to a force from the fluid, the protrusion is not easily deformed.

[0013] In the present invention, preferably, the rotor includes a radial bearing, the radial bearing is held inside the cylindrical portion and is rotatably supported by the support shaft, and the contact surface is a first end surface of the radial bearing facing the one side. Thus, the first end surface of the radial bearing becomes the contact surface, and thus the strength of the contact surface can be enhanced.

[0014] In the present invention, it is preferred that the rotor has a through hole that penetrates the first cylindrical portion in the radial direction, and the inclined surface is located closer to the other side than the through hole. In this way, garbage and the like that flows into between the rotor and the partition wall passes through the through hole together with the fluid and flows into the impeller from the inside of the first cylindrical portion. As a result, garbage and the like that flows into between the rotor and the partition wall can be discharged from the pump chamber.

[0015] In the present invention, it is preferred that the end portion of the inclined surface on one side overlaps the through hole in the axial direction. In this way, dust or the like flowing between the rotor and the partition wall can easily pass through the through hole together with the fluid.

[0016] In the present invention, it is preferred that the inclined surface has a curved shape that is curved so as to be concave toward the other side. In this way, the inclined surface is easily subjected to a force from the fluid that pushes the rotor toward the other side in the axial direction.

[0017] According to the present invention, since the rotor includes the inclined surface that receives the force from the fluid that presses the rotor to the other side in the axial direction when the rotor rotates in the first direction, the surface pressure between the thrust bearing and the contact surface can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a perspective view showing one embodiment of a pump device to which the present invention is applied. Figure 2 yes Figure 1 A cross-sectional view of a pump arrangement is shown. Figure 3 It is an exploded perspective view of the impeller, rotor and support shaft. Figure 4 It is a longitudinal cross-sectional view of the rotor. Figure 5 This is an exploded perspective view of the rotor. Figure 6 It is a three-dimensional diagram of the cylindrical part. Figure 7 It is a cross-sectional view of the cylindrical portion. Figure 8 This is a top view of the rotor as seen from one side. Fig. 9 It is a diagram for explaining the protrusion of the rotor. Fig.10 It is a diagram for explaining the forces acting on the rotor. DETAILED DESCRIPTION

[0019] Hereinafter, the motor and pump device according to the embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the axial direction refers to the direction along the rotation axis L, the radial direction of the radial inside and the radial outside refers to the radial direction with the rotation axis L as the center, and the circumferential direction refers to the rotation direction with the rotation axis L as the center.

[0020] (Overall structure) Figure 1 This is a perspective view showing one embodiment of a pump device 1 to which the present invention is applied. Figure 2 yes Figure 1 A sectional view of a pump device 1 is shown. Figure 3 FIG. 2 is an exploded perspective view of the impeller 25, the rotor 4 and the support shaft 5. Figure 1 and Figure 2 In the embodiment, the pump device 1 includes: a housing 2; a motor 10 arranged on the other side L2 in the axial direction relative to the housing 2; and an impeller 25 arranged in the pump chamber 20 inside the housing 2. The impeller 25 is driven by the motor 10 to rotate around the rotation axis L. The motor 10 includes: a cylindrical stator 3; a rotor 4 arranged on the inner side of the stator 3; a resin casing 6 covering the stator 3; and a round rod-shaped support shaft 5 that supports the rotor 4 so that it can rotate. 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 as a vehicle-mounted pump in which the ambient temperature and the fluid temperature are easily changed.

[0021] The housing 2 is fixed to one side L1 of the motor 10 and is divided into a pump chamber 20 for accommodating an impeller 25. The housing 2 includes: 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. The suction pipe 21 includes a suction port 21a. The discharge pipe 22 includes a discharge port 22a. The suction pipe 21 is provided concentrically with respect to the rotation axis L.

[0022] The stator 3 includes a stator core 31 , an insulator 32 held by the stator core 31 , and a coil 35 wound around the stator core 31 via the insulator 32 .

[0023] like Figure 3 As shown, the rotor 4 rotates in the first rotation direction CW around the rotation axis L. Figure 2 and Figure 3 As shown, the rotor 4 has a cylindrical portion 40 extending from a position opposite to the stator 3 on the radial inner side to the pump chamber 20 along the axial direction. The cylindrical portion 40 is made of resin. The cylindrical portion 40 opens in the pump chamber 20. A cylindrical magnet 80 opposite to the radial inner side of the stator 3 is held on the outer peripheral surface of the cylindrical portion 40. The magnet 80 is a rare earth magnet.

[0024] A disc-shaped flange portion 45 is formed at the end of one side L1 in the axial direction of the cylindrical portion 40. The impeller 25 is fixed to the flange portion 45. The impeller 25 is made of resin. A central hole 250 is formed in the central portion of the impeller 25. The impeller 25 is formed with a plurality of blade portions 251 at equal angular intervals, and the plurality of blade portions are curved in an arc shape from the periphery of the central hole 250 and extend radially outward. The impeller 25 is fixed to the flange portion 45 via the blade portions 251.

[0025] like Figure 2 As shown, a cylindrical radial bearing 11 is held on the radial inner side of the cylindrical portion 40. The rotor 4 is rotatably supported on the support shaft 5 by the radial bearing 11. The first end portion 51 on the other side L2 in the axial direction of the support shaft 5 is held in the shaft hole 65 formed in the third partition wall 63 of the housing 6. An annular thrust bearing 12 is mounted on the second end portion 52 of the support shaft 5. The thrust bearing 12 is an annular plate member. The thrust bearing 12 contacts a contact surface 410 of the rotor 4 facing one side, and supports the rotor 4 in the thrust direction. In the present embodiment, the contact surface 410 is the first end surface 110 of the radial bearing 11 facing the one side L1. The thrust bearing 12 is arranged between the radial bearing 11 and the cylindrical portion 28 provided in the housing 2. As a result, the movement of the thrust bearing 12 in the axial direction is restricted.

[0026] Here, the first end portion 51 and at least a portion of the shaft hole 65 are formed to have a D-shaped cross section, and the second end portion 52 of the support shaft 5 and the hole of the thrust bearing 12 are formed to have a D-shaped cross section. Therefore, the rotation of the support shaft 5 and the thrust bearing 12 is prevented. In addition, the cross section of the second end portion 52 of the support shaft 5 and the hole of the thrust bearing 12 may not be a D-shape but a circular shape.

[0027] like Figure 1 and Figure 2 As shown, the housing 6 is covered with the housing 2 from one side L1 to divide the pump chamber 20, and is provided with: a partition wall 60 disposed between the rotor 4 and the stator 3; and a cylindrical main body 66 covering the stator 3 from the radially outer side. The partition wall 60 includes: a first partition wall 61 covered with the housing 2 from one side L1; a second partition wall 62 between the stator 3 and the magnet 80; and a third partition wall 63 blocking the other side L2 of the second partition wall 62. The first partition wall 61 is an annular surface facing the one side L1 and facing the housing 2. The second partition wall 62 is cylindrical and extends from the opening in the center of the first partition wall 61 to the other side L2.

[0028] The housing 6 is composed of a resin sealing member 70 that covers the stator 3 from both radial sides and both axial sides. The resin sealing member 70 is a resin portion obtained by insert molding the stator 3 using polyphenylene sulfide (PPS) or the like.

[0029] like Figure 2 As shown, a cover 18 is fixed to the end 64 on the other side L2 of the axial direction of the housing 6 from the other side L2 of the rotation axis L. A circuit substrate 19 is arranged between the cover 18 and the third partition wall 63 of the housing 6, and the circuit substrate 19 is provided with a circuit for controlling the power supply to the coil 35, etc.

[0030] (Details of the rotor) Figure 4 It is a longitudinal sectional view of the rotor 4 . Figure 5 It is an exploded perspective view of the rotor 4. Figure 6 It is a perspective view of the cylindrical portion 40 . Figure 7 It is a cross-sectional view of the cylindrical portion 40 . Figure 8 It is a plan view of the rotor 4 as seen from one side L1. Fig. 9 It is a diagram for explaining the protrusion 44 of the rotor 4 . Fig.10 It is a diagram for explaining the force acting on the rotor 4 .

[0031] like Figure 3 to Figure 6 As shown, the rotor 4 includes a cylindrical portion 40 having a cylindrical shape and a magnet 80 held outside the cylindrical portion 40. The cylindrical portion 40 includes: a first cylindrical portion 41 connected to the impeller 25; a second cylindrical portion 42 located on the other side L2 of the first cylindrical portion 41 and holding the magnet 80 outside; and a seat portion 43 protruding radially outward between the first cylindrical portion 41 and the second cylindrical portion 42 and supporting one side L1 of the magnet 80.

[0032] The first cylindrical portion 41 and the second cylindrical portion 42 are cylindrical and coaxially arranged. The outer dimension of the second cylindrical portion 42 is larger than the outer diameter of the first cylindrical portion 41. The flange portion 45 protrudes radially outward from one end of the first cylindrical portion 41.

[0033] The seat portion 43 is provided with a convex portion 431 which is engaged with a concave portion 811 formed on the end portion 81 of one side L1 of the magnet 80. The convex portion 431 is engaged with the concave portion 811 to define the angular position of the magnet 80 in the circumferential direction and prevent the magnet 80 from rotating. The end portion of the second cylindrical portion 42 on the other side L2 is provided with a rivet portion 421 overlapping with the magnet 80. The magnet 80 is fixed to the second cylindrical portion 42 by the rivet portion 421 while being pressed into the second cylindrical portion 42.

[0034] The cylindrical portion 40 includes: a third cylindrical portion 47 that holds the radial bearing 11 inside; and an annular plate portion 48 that protrudes from the inner peripheral surface of the first cylindrical portion 41 and connects to the third cylindrical portion 47. The radial bearing 11 is accommodated inside the third cylindrical portion 47. The radial bearing 11 is positioned relative to the third cylindrical portion 47 in the axial direction by the contact between the flange portion 111 of the radial bearing 11 and the annular end surface 471 of the third cylindrical portion 47. The step portion 472 provided at the end of the one side L1 of the third cylindrical portion 47 contacts the annular step portion 112 provided on the outer peripheral surface of the flange portion 111 of the radial bearing 11 from the one side L1. As a result, the movement of the radial bearing 11 to the one side L1 relative to the third cylindrical portion 47 is restricted.

[0035] like Figure 4 , Figure 7 and Figure 8 As shown, a plurality of through holes 49 are provided in the annular plate portion 48 and pass through in the axial direction. In this embodiment, six through holes 49 are provided at equal angles in the circumferential direction. Through the through holes 49, the interior of the first cylindrical portion 41 is connected to the interior of the second cylindrical portion 42.

[0036] like Figure 3 , Figure 5 , Figure 6 , Figure 7 and Fig. 9 As shown, the rotor 4 includes: a protrusion 44 protruding radially outward from the outer circumferential surface of the first cylindrical portion 41; and a through hole 46 penetrating the first cylindrical portion 41 in the radial direction. Two protrusions 44 are provided at positions 180 degrees apart from each other in the circumferential direction. The protrusion 44 is integrated with an end 43a of one side L1 of the seat portion 43. The protrusion 44 includes an inclined surface 441 facing the one side L1. The inclined surface 441 is inclined in a manner that receives force from the fluid in the pump chamber 20 when the rotor 4 rotates in the first rotation direction CW. The inclined surface 441 has a curved shape that is curved in a manner that is recessed toward the other side L2.

[0037] A plurality of through holes 46 are provided at equal angles in the circumferential direction. In this embodiment, two through holes 46 are provided in the circumferential direction. Fig. 9 As shown, the inclined surface 441 is located closer to the other side L2 than the through hole 46 , and one end 441 a of the inclined surface 441 overlaps with the through hole 46 in the axial direction.

[0038] like Fig.10 As shown in FIG. 1 , when the impeller 25 (rotor 4) rotates in the first rotation direction CW, the inclined surface 441 is inclined in such a manner that it receives force from the fluid in the pump chamber 20, and therefore, a force acts on the inclined surface 441 toward the other side L2. That is, the inclined surface 441 receives a force from the fluid in the pump chamber 20 that pushes the rotor 4 toward the other side L2. As a result, the force on the other side L2 is as follows: Fig.10 Since the thrust bearing 12 acts on the rotor 4 as indicated by the arrow B, the surface pressure between the thrust bearing 12 and the first end surface 110 of the radial bearing 11 is reduced.

[0039] In addition, when the rotation speed of the impeller 25 increases, the pressure change in the pump chamber 25 increases, so the force pushing the rotor 4 to one side increases, but the force received by the inclined surface 441 from the fluid in the pump chamber 20 also increases, so the force pushing the rotor 4 to the other side also increases. Therefore, the surface pressure between the thrust bearing 12 and the first end surface 110 of the radial bearing 11 decreases according to the rotation speed of the impeller 25.

[0040] Here, when the impeller 25 rotates in the first rotation direction CW, the dirt and the like contained in the fluid may not be discharged from the discharge port 22a but flow into between the flange portion 45 and the partition wall 60. At this time, the inclined surface 441 is located at the other side L2 relative to the through hole 46, and the end 441a of one side of the inclined surface 441 overlaps with the through hole 46 in the axial direction. Therefore, the fluid flowing along the inclined surface 441 is Fig.10 The fluid flows toward the through hole 46 as shown by the arrow A, and is guided into the first cylindrical portion 41 through the through hole 46. Thus, the fluid containing the dust and the like flows from the first cylindrical portion 41 into the impeller 25 through the through hole 46, and is discharged from the discharge port 22a.

[0041] (Function and Effect) The pump of this embodiment includes: a rotor 4 that rotates in a first rotation direction CW with a rotation axis L as a center; a support shaft 5 that supports the rotor 4 so that it can rotate; a stator 3 that is arranged around the rotor 4; an impeller 25 that is connected to the rotor 4 on one side L1 in the axial direction of the rotor 4; a housing 2 that divides a pump chamber 20 that accommodates the impeller 25; a partition wall 60 that is covered by the housing 2 from one side L1 to divide the pump chamber 20 and is arranged between the rotor 4 and the stator 3; and a thrust bearing 12 that contacts a contact surface 410 of the rotor 4 that faces the one side L1 and supports the rotor 4 in the thrust direction. The rotor 4 includes a protrusion 44 that protrudes radially outward from the outer peripheral surface of the rotor 4. The protrusion 44 includes an inclined surface 441, which faces the one side L1, and when the rotor 4 rotates in the first rotation direction CW, the fluid in the pump chamber 20 receives a force that pushes the rotor 4 toward the other side L2 in the axial direction.

[0042] According to the present embodiment, when the rotor 4 rotates in the first direction CW, the inclined surface 441 receives a force from the fluid that presses the rotor 4 toward the other side L2 in the axial direction, thereby reducing the surface pressure between the thrust bearing 12 and the contact surface 410. This can suppress reduction in the life of the thrust bearing 12 and the contact surface 410.

[0043] Since the surface pressure between the thrust bearing 12 and the contact surface 410 can be reduced, even when the rotor 4 is rotated at a high speed, an increase in the current flowing through the motor 10 of the pump device 1 can be suppressed, and vibration of the pump device 1 can be suppressed.

[0044] Two protrusions 44 are provided in the circumferential direction with the rotation axis as the center. In this way, compared with the case where there is only one protrusion 44, the force that pushes the rotor 4 toward the other side L2 in the axial direction is uniform with the rotation axis as the center. Therefore, even when the rotor 4 is pressed toward the other side L2 in the axial direction, the rotor 4 can be stably rotated. In addition, since the two protrusions 44 are separated from each other by 180 degrees in the circumferential direction, when the protrusion 44 is formed by resin, it is easy to form the protrusion by a mold.

[0045] The protrusion 44 is formed integrally with the end portion 43a on the one side L1 of the seat portion 43. As a result, the strength of the protrusion is improved, and therefore, even when the inclined surface receives a force from the fluid, the protrusion is less likely to deform.

[0046] The rotor 4 includes a radial bearing 11, which is held inside the cylindrical portion 40 and rotatably supported on the support shaft 5. The contact surface 410 is a first end surface 110 of the radial bearing 11 facing one side. Thus, the first end surface 110 of the radial bearing 11 serves as the contact surface 410, and thus the strength of the contact surface 410 can be increased.

[0047] The rotor 4 has a through hole 46 that radially passes through the first cylindrical portion 41. The inclined surface 441 is located closer to the other side L2 than the through hole 46. In this way, the dust and the like that flows into between the rotor 4 and the partition wall 60 passes through the through hole 46 together with the fluid, and flows from the inside of the first cylindrical portion 41 into the inside of the impeller 25. Thus, the dust and the like that flows into between the rotor 4 and the partition wall 60 can be discharged from the pump chamber 20.

[0048] The end portion 441a of the inclined surface 441 on one side L1 overlaps the through hole 46 in the axial direction. Thus, dust or the like flowing between the rotor 4 and the partition wall 60 can easily pass through the through hole 46 together with the fluid.

[0049] The inclined surface 441 has a curved shape that is curved so as to be recessed toward the other side L2. Thus, the inclined surface 441 is easily subjected to a force from the fluid that pushes the rotor 4 toward the other side L2.

[0050] (Variation Example) In the above embodiment, two protrusions 44 are provided, but the number of protrusions 44 is not limited to two. The number of protrusions 44 may be three or more. In addition, a plurality of protrusions 44 may be arranged in the axial direction.

[0051] In the above embodiment, the protrusion 44 is integrated with the end portion 43 a on the one side L1 of the seat portion 43 , but the protrusion 44 may be separated from the seat portion 43 .

[0052] In the above embodiment, the inclined surface 441 has a curved shape, but the inclined surface 441 may have a flat shape.

[0053] Note that the present technology can adopt the following configurations.

[0054] (1) A pump device comprising: A rotor that rotates in a first rotation direction around a rotation axis; a support shaft that rotatably supports the rotor; a stator disposed around the rotor; an impeller connected to the rotor at one side of the rotor along the axial direction of the rotation axis; a casing that divides a pump chamber for accommodating the impeller; a partition wall which is covered by the housing from the one side to partition the pump chamber and is arranged between the rotor and the stator; and a thrust bearing which contacts the contact surface of the rotor facing the one side and supports the rotor in a thrust direction, The rotor includes a protrusion that protrudes radially outward from an outer peripheral surface of the rotor. The protrusion has an inclined surface that faces the one side and receives a force for pressing the rotor toward the other side in the axial direction from the fluid in the pump chamber when the rotor rotates in the first rotation direction.

[0055] (2) In the pump device described in (1), A plurality of the protrusions are provided at equal angles in a circumferential direction around the rotation axis.

[0056] (3) In the pump device described in (2), Two protrusions are provided in the circumferential direction.

[0057] (4) In the pump device described in any one of (1) to (3), The rotor includes a cylindrical portion and a magnet held outside the cylindrical portion. The cylindrical portion includes: a first cylindrical portion connected to the impeller; a second cylindrical portion located on the other side of the axial direction of the first cylindrical portion and holding the magnet on the outside; and a seat portion protruding radially outward between the first cylindrical portion and the second cylindrical portion and supporting the one side of the magnet. The protrusion protrudes radially outward from the outer peripheral surface of the first cylindrical portion.

[0058] (5) In the pump device described in (4), The protrusion is integrated with the one end portion of the seat.

[0059] (6) In the pump device described in (4) or (5), The rotor includes a radial bearing held inside the cylindrical portion and rotatably supported by the support shaft. The contact surface is a first end surface of the radial bearing facing the one side.

[0060] (7) In the pump device described in any one of (4) to (6), The rotor includes a through hole that penetrates the first cylindrical portion in a radial direction. The inclined surface is located closer to the other side than the through hole.

[0061] (8) In the pump device described in (7), The one end portion of the inclined surface overlaps with the through hole in the axial direction.

[0062] (9) In the pump device described in any one of (1) to (8), The inclined surface has a curved shape that is curved so as to be recessed toward the other side. Explanation of symbols

[0063] 1 ... pump device, 2 ... housing, 3 ... stator, 4 ... rotor, 5 ... support shaft, 6 ... housing, 10 ... motor, 11 ... radial bearing, 12 ... thrust bearing, 18 ... cover, 19 ... circuit board, 20 ... pump chamber, 21 ... suction pipe, 21a ... suction port, 22 ... discharge pipe, 22a ... discharge port, 25 ... impeller, 28 ... cylinder, 31 ... stator core, 32 ... insulator, 35 ... coil, 40 ... cylinder, 41 ... first cylinder portion, 42 ... second cylinder portion, 43 ... seat portion, 43a ... end portion, 44 ... protrusion, 45 ... flange portion, 46 ... through hole, 47 ... third cylinder portion, 48 ... annular plate portion, 49 ... through hole, 5 1…first end portion, 52…second end portion, 60…partition wall, 61…first partition wall, 62…second partition wall, 63…third partition wall, 64…end portion, 65…axial hole, 66…main body portion, 70…resin sealing member, 80…magnet, 81…end portion, 110…first end surface, 111…flange portion, 112…step portion, 250…central hole, 251…blade portion, 410…contact surface, 421…rivet portion, 431…convex portion, 441…inclined surface, 441a…end portion, 471…annular end surface, 472…step portion, 811…recessed portion, CW…first rotation direction, L…rotation axis, L1…one side, L2…other side.

Claims

1. A pump device, characterized in that: have: A rotor, the rotor rotating in a first rotation direction around a rotation axis; a support shaft that rotatably supports the rotor; a stator, the stator being arranged around the rotor; an impeller connected to the rotor at one side of the rotor along the axial direction of the rotation axis; a casing, the casing dividing a pump chamber for accommodating the impeller; a partition wall that is covered by the housing from the one side to partition the pump chamber and is disposed between the rotor and the stator; and a thrust bearing that contacts the contact surface of the rotor facing the one side and supports the rotor in a thrust direction, The rotor includes a protrusion that protrudes radially outward from an outer peripheral surface of the rotor. The protrusion has an inclined surface that faces the one side and receives a force from the fluid in the pump chamber to press the rotor toward the other side in the axial direction when the rotor rotates in the first rotation direction.

2. The pump device according to claim 1, characterized in that A plurality of the protrusions are provided at equal angles in a circumferential direction around the rotation axis.

3. The pump device according to claim 2, characterized in that Two protrusions are provided in the circumferential direction.

4. The pump device according to any one of claims 1 to 3, characterized in that The rotor includes a cylindrical portion and a magnet held outside the cylindrical portion. The cylindrical portion includes: a first cylindrical portion connected to the impeller; a second cylindrical portion located on the other side of the axial direction of the first cylindrical portion and holding the magnet on the outside; and a seat portion protruding radially outward between the first cylindrical portion and the second cylindrical portion and supporting the one side of the magnet. The protrusion protrudes radially outward from the outer peripheral surface of the first cylindrical portion.

5. The pump device according to claim 4, characterized in that The protrusion is integrated with the one end portion of the seat.

6. The pump device according to claim 4, characterized in that The rotor includes a radial bearing held inside the cylindrical portion and rotatably supported by the support shaft. The contact surface is a first end surface of the radial bearing facing the one side.

7. The pump device according to claim 4, characterized in that The rotor includes a through hole that penetrates the first cylindrical portion in a radial direction. The inclined surface is located closer to the other side than the through hole.

8. The pump device according to claim 7, characterized in that The one end portion of the inclined surface overlaps with the through hole in the axial direction.

9. The pump device according to claim 1, characterized in that The inclined surface has a curved shape that is curved so as to be recessed toward the other side.

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