Pump

Abstract

A pump (1) is provided with a casing (3) having a discharge port (33). The casing (3) is provided with a deformable surface (38) and a plurality of ribs (37) provided on the surface (38). The plurality of ribs (37) extend from the inside (38a) toward the outside (38b) of the surface (38), and a first rib (37A) from among the plurality of ribs (37) has a first portion (37c) curved in the circumferential direction.

Description

Pump

[0001] The present invention relates to a pump.

[0002] For example, Patent Document 1 discloses a pump in which a plurality of ribs are provided on the upper surface of a casing. In one example, the plurality of ribs each extend linearly in a radial direction from the liquid inlet. For example, when the inlet is connected to a water pipe, the internal pressure in the pump increases.

[0003] Japanese Unexamined Patent Application Publication No. 2019-157701

[0004] Due to the increase in internal pressure, the upper surface of the casing tends to deform so as to bulge upward centering on the inlet. At this time, stress concentrates on a connection portion, for example, with a side surface of the rib that extends linearly in the radial direction. The portion where stress concentrates can become a starting point for rib fracture.

[0005] The present invention has been made in view of the above problems, and an object of the present invention is to provide a pump capable of suppressing stress concentration on ribs.

[0006] A pump according to one aspect of the present invention includes a casing having a discharge port, the casing includes a deformable surface and a plurality of ribs provided on the surface, the plurality of ribs extend from an inner side to an outer side of the surface, and a first rib among the plurality of ribs has a first portion curved in a circumferential direction.

[0007] FIG. 1 is a perspective view schematically showing the structure of a pump 1 according to an embodiment of the present invention. It is a cross-sectional view taken along line 2-2 in FIG. 1. It is a cross-sectional view taken along line 3-3 in FIG. 2. It is a plan view schematically showing the structure of a casing 3 according to a specific example. It is a cross-sectional view taken along line 5-5 in FIG. 4. It is a cross-sectional view taken along line 6-6 in FIG. 4. It is a partially enlarged plan view schematically showing the structure of a part of the casing 3 according to a specific example. It is a partially enlarged perspective view schematically showing the structure of a part of the casing 3 according to a specific example.

[0008] An embodiment of the present invention will be described below with reference to the attached drawings. Figure 1 is a schematic perspective view showing the structure of a pump 1 according to an embodiment of the present invention. This pump 1 is, for example, a water pump. A water pump is a centrifugal pump for transferring (pressurizing) fluids, i.e., liquids. In one example, the pump 1 is connected to a floor heating system that uses tap water and is used to transfer tap water from a water pipe to the floor heating system. In addition, the pump 1 may be used to transfer coolant to, for example, the engine room of a gasoline-powered vehicle or the motor room of an electric vehicle (EV).

[0009] In pump 1, the direction along axis x is defined as the axial direction. In this axial direction, one side is defined as the upper side, and the other side in the opposite direction of the upper side is defined as the lower side. The upper and lower sides do not necessarily coincide with the upper and lower sides in the direction of gravity. Furthermore, the direction perpendicular to axis x is defined as the radial direction. In the radial direction, the direction approaching axis x is defined as the inner circumference, and the direction moving away from axis x is defined as the outer circumference. In addition, the direction around axis x is defined as the circumferential direction. In the circumferential direction, clockwise and counterclockwise directions are defined. The clockwise and counterclockwise directions are defined as the directions when viewed from the upper side in the axial direction.

[0010] Pump 1 includes a housing 2 that is generally cylindrical in shape with respect to an axis x. The housing 2 has a casing 3, a case 4, and a cover 5. In this example, the casing 3 covers the upper side of the case 4, while the cover 5 covers the lower side of the case 4. The casing 3, case 4, and cover 5 are each formed (e.g., by injection molding) from a thermoplastic resin material, such as PPS (polyphenylene sulfide). The PPS may be filled with, for example, glass fiber fillers. The cover 5 may be formed from a metal material, such as aluminum, instead of a resin material.

[0011] The casing 3 has a main body 31 formed in an annular shape around an axis x, and an inlet 32 ​​and an outlet 33 integrally formed on the main body 31. The main body 31 as a whole has a flat cylindrical outer shape centered on the axis x. In one example, the inlet 32 ​​is formed to protrude upward from the main body 31 along the axis x. The inlet 32 ​​is formed, for example, in a cylindrical shape centered on the axis x. The inlet 32 ​​can allow fluid (for example, tap water) to flow into the internal space of the housing 2, which will be described later. Note that the inlet 32 ​​may be formed directly on the upper surface of the main body 31. That is, the inlet 32 ​​does not have to protrude upward from the main body 31.

[0012] In one example, the discharge port 33 is formed to protrude outward from the side of the main body 31 along the tangent to a virtual circle defined with the position of axis x as the center in a virtual plane perpendicular to axis x. The discharge port 33 allows fluid to flow out from the internal space of the housing 2. In this way, the liquid (tap water in one example) that flows into the internal space of the housing 2 axially through the inlet 32 ​​flows out to the outside from the internal space of the housing 2 in a tangential direction through the discharge port 33. Note that the discharge port 33 may be formed directly on the side of the main body 31. That is, the discharge port 33 does not have to protrude outward from the main body 31. Details of the structure of the casing 3 will be described later.

[0013] Figure 2 is a cross-sectional view along line 2-2 in Figure 1. Referring to both Figures 1 and 2, the case 4 has a lower section 41, an inner wall 42, an upper section 43, and an outer wall 44. The inner wall 42 and the outer wall 44 are formed in a cylindrical shape centered on axis x. In the radial direction, the outer circumferential surface of the inner wall 42 faces the inner circumferential surface of the outer wall 44. The lower end of the inner wall 42 is closed by the lower section 41. The upper section 43 is formed as an annular plate along a plane perpendicular to axis x. The upper section 43 connects the upper ends of the inner wall 42 and the outer wall 44 to each other. In a plan view in the axial direction, the upper section 43 is located on the outer circumferential side of the lower section 41. In this example, the main body 31 of the casing 3 is supported by the upper section 43 and the upper ends of the outer wall 44.

[0014] In the housing 2, a first internal space S1 and a second internal space S2 are formed by the casing 3 and the case 4. The first internal space S1 is formed by the main body 31 of the casing 3 and the upper part 43 of the case 4. The second internal space S2 is formed by the lower part 41 of the case 4 and the inner wall 42. In this example, the first internal space S1 and the second internal space S2 are defined, for example, as roughly cylindrical spaces centered on axis x. The inlet 32 ​​and the outlet 33 are connected to the first internal space S1. Tap water that flows downward from the inlet 32 ​​along axis x into the first internal space S1 flows radially and circumferentially within the first internal space S1, and then is discharged to the outside of the pump 1 roughly radially through the outlet 33.

[0015] The lower end of case 4 is closed by cover 5. Specifically, cover 5 is attached to the lower end of the outer wall 44 of case 4. Cover 5 is formed, for example, of a disc-shaped flat plate that extends along a plane perpendicular to the axis x. In the axial direction, cover 5 faces the lower part 41 of case 4. In housing 2, a third internal space S3 is formed by case 4 and cover 5. The third internal space S3 is formed by the lower part 41, inner wall 42, upper part 43 and outer wall 44 of case 4 and cover 5. The third internal space S3 is separated from the first internal space S1 and the second internal space S2 by case 4. The third internal space S3 surrounds the second internal space S2 in the radial direction.

[0016] Figure 3 is a cross-sectional view along line 3-3 in Figure 2. Referring to both Figures 2 and 3, a motor 6 is incorporated within the housing 2. The motor 6 includes a stator 7 and a rotor 8 that is rotatable relative to the stator 7 around axis x. The stator 7 is positioned radially on the outer circumference of the rotor 8. The stator 7 as a whole is formed in an annular shape with axis x as its central axis. This annular stator 7 is positioned in a part of the annular third internal space S3 between the inner wall 42 and the outer wall 44. In one example, the stator 7 is fixed, for example, to the inner circumferential surface of the outer wall 44. However, the stator 7 may also be fixed, for example, to the outer circumferential surface of the inner wall 42.

[0017] The stator 7 comprises a stator core 71, a plurality of coils 72, and an insulator 73. The stator core 71 is formed from a laminate of multiple thin plates (magnetic material) stacked in the axial direction. The laminate of multiple thin plates is made of a magnetic material. The coils 72 are windings made of, for example, copper wire. The insulator 73 is placed between the stator core 71 and the coils 72. In this way, the insulator 73 electrically insulates the stator core 71 from the plurality of coils 72. The insulator 73 is made of an insulating material. The insulating material includes, for example, a resin material.

[0018] As shown in Figure 3, the stator core 71 has an annular portion 74, a plurality of (six in this example) magnetic pole portions 75, and spokes 76 connecting the annular portion 74 and each magnetic pole portion 75. The annular portion 74 is defined in an annular shape around the axis x. In this example, the annular portion 74 is fixed to the inner circumferential surface of the outer wall 44 of the case 4. Each spoke 76 protrudes inward from the inner circumferential surface of the annular portion 74. The inner circumferential surface of each magnetic pole portion 75 faces the inner wall 42 of the case 4. The windings of the coil 72 are wound around the insulator 73 that covers each magnetic pole portion 75. The number of magnetic pole portions 75 may be any number, such as nine or eighteen. Thus, the number of poles of the rotor 8 may be changed in accordance with the change in the number of magnetic pole portions 75.

[0019] Returning to Figure 2, the rotor 8 is rotatably supported about axis x on a shaft 21 held in the housing 2. In this example, the shaft 21 extends axially within the second internal space S2. The shaft 21 is formed, for example, in a cylindrical shape centered on axis x. The upper end of the shaft 21 is fixed to a retaining portion 34 of the casing 3. The retaining portion 34 has a body 34a of the retaining portion 34 and one or more spokes 34b that connect the body 34a of the retaining portion 34 to the body 31 of the casing 3. In this example, three spokes 34b are arranged circumferentially at predetermined intervals (for example, equally spaced). The body 34a and spokes 34b are integrally formed with the body 31.

[0020] The main body 34a of the holding portion 34 is positioned to enter the first internal space S1 and the second internal space S2 from the lower end of the inlet 32 ​​along the axis x. In this example, the main body 34a extends further down in the axial direction than the lower end of the main body 31. The main body 34a extends in a long length along the axis x. The three spokes 34b extend from the upper end side of the main body 34a to the inner circumferential surface of the inlet 32. Each spoke 34b is formed, for example, of a flat plate extending along a plane containing the axis x. The upper end of the shaft 21 is held and fixed, for example, by press-fitting, into a recess (a hole with a bottom) formed on the lower surface of the main body 34a.

[0021] On the other hand, the lower end of the shaft 21 is fixed to the lower part 41 of the case 4. In this example, the lower part 41 has an annular portion 41a formed in an annular shape and a projection 41b that protrudes upward in the axial direction from the annular portion 41a. The annular portion 41a is formed, for example, from an annular flat plate extending along a plane perpendicular to the axis x. The outer peripheral end of the annular portion 41a is continuous with the lower end of the inner wall 42. The projection 41b extends upward from the annular portion 41a within the second internal space S2. The lower end of the shaft 21 is held and fixed by press-fitting into the recess (hole with a bottom) of the projection 41b. Note that a through hole may be formed in the projection 41b instead of a recess (hole with a bottom).

[0022] The rotor 8 is housed within the first internal space S1 and the second internal space S2 of the housing 2. The rotor 8 includes a bearing 81, an impeller 82, and a magnet 83. In one example, the bearing 81 is formed in a cylindrical shape along the axis x. The inner circumferential surface of the bearing 81 faces the outer circumferential surface of the shaft 21 with a predetermined gap between them. Thus, the bearing 81 is configured to be rotatable relative to the shaft 21 about the axis x and to be displaceable relative to the shaft 21 in the vertical direction along the axis x. In other words, the bearing 81 is a so-called sliding bearing. The bearing 81 is made of, for example, a resin material. An annular washer 87 may be placed between the upper surface of the bearing 81 and the lower surface of the main body 34a of the retaining part 34.

[0023] The impeller 82 is fixed to the bearing 81 so as not to rotate relative to it. The impeller 82 has a cylindrical portion 84, a base 85, and a plurality of blades 86. The impeller 82 is made of a thermoplastic resin material, such as PPS (polyphenylene sulfide). The cylindrical portion 84 is formed in a generally cylindrical shape with axis x as the center. The bearing 81 is fixed inside the cylindrical portion 84. The base 85 is integrally formed at the upper end of the cylindrical portion 84. The base 85 is formed in a disc shape with axis x as the center. A plurality of blades 86 rise upward from the upper surface of the base 85. Each blade 86 is arranged in a spiral shape in a plan view by curving and extending, for example, from its inner circumference to its outer circumference.

[0024] A magnet 83 is fixed to the outer circumferential surface of the cylindrical portion 84 below the base 85. In this example, the magnet 83 is formed in a cylindrical shape with axis x as the center. The magnet 83 is, for example, a permanent magnet. In the magnet 83, a region magnetized as the south pole and a region magnetized as the north pole are defined in the circumferential direction. In the rotor 8, the base 85 and the blades 86 are housed in a first internal space S1, while the magnet 83 and the cylindrical portion 84 are housed in a second internal space S2. The outer circumferential surface of the magnet 83 faces the inner circumferential surface of the inner wall 42 of the case 4. In this way, each magnetic pole portion 75 of the stator core 71 of the stator 7 faces the outer circumferential surface of each magnet 83 with a predetermined magnetic gap.

[0025] Returning to Figure 2, a circuit board 9 is housed in the third internal space S3. The circuit board 9 is formed in the shape of a circular flat plate that extends along a plane perpendicular to the axis x. In one example, the circuit board 9 is fixed to the insulator 73 of the stator 7. Multiple electronic components (not shown) are mounted on the top and bottom surfaces of the circuit board 9. These electronic components include, for example, field-effect transistors (FETs) and capacitors. Current and signals are supplied to the circuit board 9 from an external device via connectors and terminals (not shown) attached to the housing 2. Similarly, current is supplied from the circuit board 9 to the coil 72 via connection terminals (not shown).

[0026] Figure 4 is a schematic plan view showing the structure of a casing 3 according to one specific example. Figure 5 is a cross-sectional view along line 5-5 in Figure 4. Figure 6 is a cross-sectional view along line 6-6 in Figure 4. Referring together to Figures 1 and 4 to 6, the main body 31 of the casing 3 has an annular portion 35 with axis x as its central axis (hereinafter referred to as the "annular portion"), one or more fixing portions 36 that protrude outward from the annular portion 35 (in other words, positioned outside the outer circumference of the surface 38 described later, that is, surrounding the outer circumference of the surface 38), and a plurality of ribs 37 formed on the upper surface of the annular portion 35. The aforementioned inlet 32 ​​and outlet 33 are integrally formed in the annular portion 35. The annular portion 35, the fixing portions 36 and the plurality of ribs 37 are integrally formed.

[0027] Referring together to Figures 4 and 5, the annular portion 35 has a first plate portion 35a, a second plate portion 35b, an inner cylindrical portion (hereinafter referred to as the "inner cylindrical portion") 35c, and an outer cylindrical portion (hereinafter referred to as the "outer cylindrical portion") 35d. In one example, the first plate portion 35a and the second plate portion 35b are formed as annular flat plates extending along a plane intersecting (perpendicular to) the axis x. In the axial direction, the first plate portion 35a is positioned above the second plate portion 35b. Also, the first plate portion 35a is positioned on the inner side of the second plate portion 35b. The inlet 32 ​​is integrally formed with the first plate portion 35a. The first plate portion 35a, the second plate portion 35b, the inner cylindrical portion 35c, and the outer cylindrical portion 35d are integrally formed.

[0028] In one example, the inner cylindrical portion 35c and the outer cylindrical portion 35d are formed in a cylindrical shape with axis x as the central axis. The inner cylindrical portion 35c is located on the inner side of the outer cylindrical portion 35d. In the radial direction, the outer surface of the inner cylindrical portion 35c faces the inner surface of the outer cylindrical portion 35d. In this example, the entire outer surface of the inner cylindrical portion 35c faces a portion of the inner surface of the outer cylindrical portion 35d. The inner cylindrical portion 35c connects the outer end of the first plate portion 35a to the inner end of the second plate portion 35b. The outer cylindrical portion 35d rises upward from the outer end of the second plate portion 35b. The discharge port 33 is integrally formed with the first plate portion 35a, the second plate portion 35b, the inner cylindrical portion 35c, and the outer cylindrical portion 35d.

[0029] Referring together to Figures 1, 4, and 6, one or more fixing portions 36 are integrally formed on the outer surface of the outer cylindrical portion 35d. In this example, four fixing portions 36 are arranged at predetermined intervals (for example, at equal intervals) in the circumferential direction. Each fixing portion 36 protrudes outward from the outer cylindrical portion 35d. In one example, each fixing portion 36 is formed in a tapered shape that narrows towards the outer circumference in the radial direction when viewed from above. The fixing portion 36 has a through hole 36a for receiving a fixing member (not shown), such as a bolt. The through hole 36a penetrates the fixing portion 36 parallel to the axis x. The casing 3 is fixed to the case 4 by screwing the fixing member into a protruding portion 45 formed on the case 4 through the through hole 36a. In this example, the protruding portion 45 protrudes outward from the outer surface of the outer wall 44.

[0030] Multiple ribs 37 are provided on a surface 38 formed by the upper surface of the first plate portion 35a of the annular portion 35, the outer surface of the inner cylindrical portion 35c, and the upper surface of the second plate portion 35b. Each rib 37 is integrally formed with the surface 38. Multiple ribs 37 are continuous with the inner surface of the outer cylindrical portion 35d. As will be described later, the surface 38 is a deformable surface. Multiple ribs 37 as a whole generally extend in the radial direction. Specifically, each rib 37 extends from the inner circumferential portion 38a on the inside (inner side) of the surface 38 to the outer circumferential portion 38b on the outside (outer side). In this example, the inner circumferential portion 38a of the surface 38 is defined, in one example, by the upper surface of the first plate portion 35a. The outer circumferential portion 38b of the surface 38 is defined, in one example, by the outer surface of the inner cylindrical portion 35c, the upper surface of the second plate portion 35b, and the inner circumferential surface of the outer cylindrical portion 35d.

[0031] As shown in Figures 5 and 6, each of the multiple ribs 37 has a smooth end face 37a that extends radially. In this example, all end faces 37a of all ribs 37 are defined along a virtual plane perpendicular to the axis x. In this example, the end faces 37a are defined flush with the upper surface of the outer cylindrical portion 35d and the upper surface of the fixing portion 36. That is, the end faces 37a of the ribs 37, the upper surface of the outer cylindrical portion 35d and the upper surface of the fixing portion 36 are defined along the same virtual plane perpendicular to the axis x. The outer periphery 38b of the surface 38 has a recess 39 that extends circumferentially. The recess 39 is divided by the discharge port 33. Furthermore, the recess 39 is divided by the multiple ribs 37. The aforementioned fixing portion 36 surrounds the outer periphery 38b of the surface 38.

[0032] Figure 7 is a partially enlarged plan view schematically showing a part of the structure of a casing 3 according to one specific example. Figure 8 is a partially enlarged perspective view schematically showing a part of the structure of a casing 3 according to one specific example. Referring together to Figures 7 and 8, in one example, the plurality of ribs 37 have a first rib 37A, a second rib 37B, and a third rib 37C that extend toward the fixing portion 36. The third rib 37C is positioned between the first rib 37A and the second rib 37B in the circumferential direction. In this example, the third rib 37C extends linearly in the radial direction. Furthermore, in the circumferential direction, the third rib 37C is aligned with the through hole 36a of the fixing portion 36. That is, the third rib 37C extends toward the center position of the fixing portion 36 in the circumferential direction.

[0033] On the other hand, the first rib 37A and the second rib 37B also extend toward the fixing portion 36. However, the first rib 37A and the second rib 37B have a straight portion 37b that extends linearly in the radial direction on the inner circumference side of the surface 38, and a curved portion (first portion or second portion) 37c that curves in the circumferential direction on the outer circumference side of the surface 38. In the first rib 37A, the curved portion 37c curves in the circumferential direction toward the third rib 37C (counterclockwise) as it moves toward the outer circumference. On the other hand, in the second rib 37B, the curved portion 37c curves in the circumferential direction toward the third rib 37C (clockwise) as it moves toward the outer circumference. In other words, the curved portion 37c of the first rib 37A and the curved portion 37c of the second rib 37B curve toward each other as they move toward the outer circumference. In other words, the curved portions 37c of the first rib 37A and the second rib 37B extend toward the fixing portion 36.

[0034] In this example, a portion of the straight section 37b is located within the recess 39 in the radial direction. On the other hand, the entire curved section 37c is located within the recess 39. By arranging the entire curved section 37c within the recess 39 in this way, elastic deformation of the curved section 37c is permitted. Also, as shown in Figure 7, the first rib 37A and the second rib 37B are formed symmetrically with respect to a plane containing axis x along the center of the third rib 37C in the circumferential direction. Also, as shown in Figure 4, the same configuration as described above is formed in the ribs 37 extending toward the other three fixing sections 36, except for the fixing section 36 adjacent to the discharge port 33. On the other hand, only the third rib 37C is located between the two circumferentially adjacent fixing sections 36, 36.

[0035] In this pump 1, when current is supplied to the coil 72 from an external device, the rotor 8 rotates around the axis x due to the magnetic interaction between the coil 72 and the magnet 83. This rotation causes the multiple blades 86 of the impeller 82 to generate a flow of tap water that flows into the first internal space S1 through the inlet 32 ​​along the axial direction. The tap water flows radially outward, passing between the circumferentially adjacent blades 86, 86, and then flows circumferentially along the inner surface of the inner cylindrical portion 35c of the main body 31. After that, the tap water flows out of the main body 31 through the discharge port 33 towards the outside of the housing 2. In this way, the pump 1 pumps tap water to, for example, a floor heating system.

[0036] In the pump 1 described above, the casing 3 is fixed to the case 4 by fixing members such as bolts at four fixing parts 36 located on the outer circumference of the annular portion 35. Therefore, when the pressure in the first internal space S1 of the housing 2 increases, the annular portion 35, i.e., the surface 38, elastically deforms on the inner circumference side of the fixing parts 36 so as to bulge upward, for example, in a dome shape. Due to this elastic deformation of the annular portion 35, i.e., the surface 38, the fixing parts 36 deform in a direction that tilts the fixing members radially outward. Specifically, the upper part of the fixing member is displaced more significantly outward than the lower part. Due to this elastic deformation of the annular portion 35, the curved portions 37c of the first rib 37A and the second rib 37B deform toward a straight line. As a result, stress concentration can be suppressed at the connection between the first rib 37A and the second rib 37B and the outer cylindrical portion 35d. Furthermore, the expression that the deformed curved portion 37c is "straight" means that the curved portion 37c is deformed to a shape close to a straight line, and that the deformed curved portion 37c is closer to a straight line than the curved portion 37c before deformation.

[0037] Furthermore, since the upper surface of the rib 37 is formed by a smooth end face 37a, no bending or step is formed in the axial direction of the rib 37. With this configuration, when the casing 3 deforms due to the increase in pressure as described above, stress does not concentrate in the bent portion or step, so that fracture of the rib 37 in the region where the stress is concentrated can be avoided. Also, in the above example, since the three first ribs 37A, second rib 37B and third rib 37C are concentrated toward the region where one fixing portion 36 extends in the circumferential direction, the rigidity of the main body 31 of the casing 3 can be increased at the fixing portion 36. Note that the fixing portions 36 may be arranged at equal intervals in three, five, or six locations in the circumferential direction. In this case, at least two ribs having curved portions 37c (first rib 37A and second rib 37B) extend toward these fixing portions 36.

[0038] In the pump 1 described above, the formation of the third rib 37C among the ribs 37 extending radially toward the fixed portion 36 may be omitted. On the other hand, two third ribs 37C may be formed between the first rib 37A and the second rib 37B. Also, a fourth rib 37D and a fifth rib 37E may be formed on the opposite side of the first rib 37A and the second rib 37B from the third rib 37C, respectively. The fourth rib 37D and the fifth rib 37E have a straight portion 37b and a curved portion 37c, similar to the first rib 37A and the second rib 37B. That is, five ribs 37 may extend toward the fixed portion 36. Furthermore, curved portions 37c may be formed on the ribs 37 extending toward the outer cylindrical portion 35d in areas other than the fixed portion 36.

[0039] Although the present invention has been described above through the embodiments described above, the technical scope of the present invention is not limited to the scope described in the embodiments above. It will be obvious to those skilled in the art that various modifications or improvements can be made to the embodiments described above. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.

[0040] The embodiments described above are for the purpose of facilitating understanding of the present invention and are not intended to limit its interpretation. Furthermore, the embodiments described above do not limit the scope of application of the present invention, and the present invention may encompass anything as its target application. The components of the above embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those exemplified and can be modified as appropriate.

[0041] For example, the present invention includes differences that arise in the implementation of manufacturing tolerances, etc. Furthermore, components shown in different embodiments can be partially substituted or combined to the extent that they do not conflict with the technical requirements. In addition, each component can be selectively combined as appropriate to achieve at least some of the above-mentioned problems and effects.

[0042] 1 Pump, 2 Housing, 21 Shaft, 3 Casing, 31 Main body, 32 Inlet, 33 Outlet, 34 Holding part, 34a Main body, 34b Spoke, 35 Annular part (Annular section), 35a First plate section, 35b Second plate section, 35c Inner cylindrical section (Inner cylindrical section), 35d Outer cylindrical section (Outer cylindrical section), 36 Fixing part, 36a Through hole, 37 Rib, 37A First rib, 37B Second rib, 37C Third rib, 37a End face, 37b Straight section, 37c Curved section (First or Second section), 37D Fourth rib, 37E Fifth rib, 38 Surface, 38a Inside (Inner circumference), 38b Outside (Outer circumference), 39 Recess, 4 Case, 41 Lower part, 41a Annular section, 41b Protruding part, 42 Inner wall, 43 Upper part, 44 Outer wall, 45 Protruding part, 5 Cover, 6 Motor, 7 Stator, 71 Stator core, 72 Coil, 73 Insulator, 74 Annular part, 75 Magnetic pole part, 76 Spoke, 8 Rotor, 81 Bearing, 82 Impeller, 83 Magnet, 87 Washer, 84 Cylinder part, 85 Base, 86 Blade, 9 Circuit board, S1 First internal space, S2 Second internal space, S3 Third internal space, x axis

Claims

1. A pump comprising a casing having a discharge port, wherein the casing comprises a deformable surface and a plurality of ribs provided on the surface, the plurality of ribs extending from the inside to the outside of the surface, and the first rib of the plurality of ribs having a first portion that is curved in the circumferential direction.

2. The pump according to claim 1, wherein the casing comprises a plurality of fixing portions surrounding the outer circumference of the surface, and the first portion extends toward the fixing portions.

3. The pump according to claim 2, wherein the deformed first portion of the casing is linear.

4. The pump according to claim 3, wherein the second rib among the plurality of ribs has a second portion that is curved in the circumferential direction, and the third rib among the plurality of ribs is positioned between the first rib and the second rib.

5. The pump according to claim 4, wherein the outer periphery of the surface is provided with recesses extending in the circumferential direction, and the recesses are divided by the plurality of ribs.

6. The pump according to claim 5, wherein each of the plurality of ribs has a smooth end face extending in the radial direction.

Images