Motor pump

Abstract

This invention relates to a motor pump. The motor pump (MP) includes: a rotor holder (200) for holding a rotor (2); and an impeller (1) which is a press-formed product, wherein the rotor holder (200) is fixed to the impeller (1).

Description

Technical Field

[0001] This invention relates to motor pumps. Prior Technology

[0002] Pumping devices comprising a motor and a pump connected by a connector are known. Such pumping devices have a structure that transmits the driving force of the motor to the impeller of the pump through the connector. [Previous Technical Documents] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2000-303986 Summary of the Invention

[0004] [The problem that the invention aims to solve]

[0005] However, in such pumping devices, the installation area increases because the pump and motor are arranged side by side. On the other hand, the increasing demand for compactness (and energy saving) in recent years has also increased the requirements for the integrated structure of the pump and motor.

[0006] Therefore, the object of the present invention is to provide a motor pump with a compact structure. [Methods for solving problems]

[0007] In one embodiment, a motor pump is provided, comprising: a rotor; a stator disposed on the radial side of the rotor; a rotor holder for holding the rotor; and an impeller, which is a press-formed product, wherein the rotor holder is fixed to the impeller.

[0008] In one embodiment, the aforementioned rotor holder comprises: an annular receiving portion formed by stamping, which receives the aforementioned rotor; and an annular cover plate that closes the aforementioned receiving portion. In one embodiment, the aforementioned rotor holder has a sealing member disposed between the aforementioned receiving portion and the aforementioned cover plate. In one state, the aforementioned rotor holder has a filler filling the aforementioned receiving portion.

[0009] In one embodiment, the aforementioned rotor holder includes a spacer disposed between the aforementioned receiving portion and the aforementioned rotor. In one embodiment, the aforementioned receiving portion has an outer annular portion and an inner annular portion disposed on the radially inner side of the aforementioned outer annular portion; the aforementioned inner annular portion has a plurality of protrusions, which form contact portions that contact the aforementioned rotor. In one state, the inner surface of the rotor that contacts the aforementioned inner annular portion has a polygonal shape.

[0010] In one embodiment, the aforementioned motor pump has a bearing that supports the aforementioned impeller and is disposed outside the flow path of the aforementioned impeller. The aforementioned bearing has a rotating side bearing body installed on the aforementioned rotor holder and a fixed side bearing body disposed on the suction side of the aforementioned rotating side bearing body. In one embodiment, the aforementioned motor pump has a stator housing that houses the aforementioned stator and is integrally formed with the aforementioned stator by resin molding. In one embodiment, the aforementioned motor pump has a motor frame that covers the outer peripheral surface of the aforementioned stator housing and is in contact with the aforementioned stator. In one state, the aforementioned rotor and the aforementioned bearing are disposed in the suction side region of the aforementioned impeller.

[0011] In one embodiment, a motor pump is provided, comprising: a rotor; a stator disposed on the radial side of the rotor; a rotor holder for holding the rotor; and an impeller, which is a resin molded article, the resin molded article being integrally formed with the rotor holder.

[0012] In one embodiment, the aforementioned rotor holder comprises: an annular receiving portion formed by a resin mold to receive the aforementioned rotor; and an annular holder to close the aforementioned receiving portion. In one state, the aforementioned annular retainer has a rotation stop structure, which forms a connection portion connected to the aforementioned receiving portion. In one state, the aforementioned rotation stop structure is an embedded hole, and a portion of the aforementioned receiving part is embedded therein.

[0013] In the first state, the aforementioned rotation stop structure is a bent part, which is bent into a U-shape. In one state, the aforementioned rotor holder has a spacer disposed between the aforementioned annular holder and the aforementioned rotor. In one state, the aforementioned annular retainer has multiple protrusions, which form contact portions that contact the aforementioned rotor.

[0014] In one state, the inner surface of the rotor that contacts the aforementioned annular holder has a polygonal shape. In one embodiment, the aforementioned motor pump has a bearing that supports the aforementioned impeller and is disposed outside the flow path of the aforementioned impeller. The aforementioned bearing has a rotating side bearing body mounted on the aforementioned rotor holder and a fixed side bearing body disposed on the suction side of the aforementioned rotating side bearing body. In one embodiment, the aforementioned motor pump has a stator housing that houses the aforementioned stator and is integrally formed with the aforementioned stator by resin molding.

[0015] In one embodiment, the aforementioned motor pump has a motor frame that covers the outer peripheral surface of the aforementioned stator housing and is in contact with the aforementioned stator. In one state, the aforementioned rotor and the aforementioned bearing are disposed in the suction side region of the aforementioned impeller. [Effects of the Invention]

[0016] The motor pump has an impeller connected to a rotor holder that holds the rotor. Therefore, it is not necessary to arrange the pump and motor side by side, resulting in a compact structure for the motor pump. Simple Explanation of the Diagram

[0017] Figure 1 shows one embodiment of the motor pump. Figure 2 shows the flow of the processing fluid through the gap between the rotating side bearing and the fixed side bearing. Figure 3 is a diagram showing one embodiment of multiple grooves formed on the flange portion of the fixed-side bearing body. Figure 4A shows one embodiment of multiple grooves formed on the cylindrical portion of the fixed-side bearing housing. Figure 4B shows another embodiment of the groove formed on the cylindrical portion of the fixed-side bearing body. Figure 4C shows another embodiment of the groove formed on the cylindrical portion of the fixed-side bearing body. Figure 5A shows one embodiment of the thrust load reduction structure located on the back of the impeller. Figure 5B is a view of Figure 5A viewed from the arrow on line A. Figure 6 shows another implementation of the thrust load reduction structure. Figure 7A shows a rotor with a stator misalignment relative to the stator. Figure 7B shows a rotor with a stator misalignment relative to the stator. Figure 8 shows one embodiment of a bearing with a tapered structure. Figure 9 shows another embodiment of a bearing with a tapered structure. Figure 10 shows a pumping unit equipped with multiple motor pumps. Figure 11 shows another embodiment of the pump unit. Figure 12 shows another embodiment of the pump unit. Figure 13A shows a diagram of a motor pump as a comparative example. Figure 13B shows another embodiment of the motor pump. Figure 13C shows another embodiment of the motor pump. Figure 14 shows one of the implementation methods of the balance adjustment method. Figure 15 shows one of the implementation methods of the balance adjustment method. Figure 16 shows one of the implementation methods of the balance adjustment method. Figure 17 shows one of the implementation methods of the balance adjustment method. Figure 18 shows one of the implementation methods of the balance adjustment method. Figure 19 shows another implementation of the balance adjustment fixture. Figure 20 shows another implementation of the balancing adjustment method. Figure 21A is a perspective view showing another embodiment of the pumping unit. Figure 21B shows a top view of the pump unit shown in Figure 21A. Figure 22 is a diagram showing the process of controlling the motor pump by the control device. Figure 23 shows another embodiment of the impeller. Figure 24 shows another embodiment of the impeller. Figure 25 shows a sealing member configured between the cover and the side plate. Figure 26 shows another embodiment of the impeller. Figure 27 shows another embodiment of the motor pump. Figure 28 shows another embodiment of the motor pump. Figure 29 shows another embodiment of the motor pump. Figure 30 shows a diagram of motor pumps with various components that can be selected according to operating conditions. Figure 31A is a cross-sectional view of another embodiment of the motor pump. Figure 31B is a view of the motor pump shown in Figure 31A when viewed from the axial direction. Figure 32A is a cross-sectional view of another embodiment of the motor pump. Figure 32B is a front view of the suction housing of the motor pump shown in Figure 32A. Figure 33 shows a pump unit with motors connected in series. Figure 34 shows another embodiment of the impeller. Figure 35 shows another embodiment of the motor pump. Figure 36 shows an enlarged view of the rotor holder. Figure 37 shows another embodiment of the spacer. Figure 38 shows a diagram of the rotor inserted into the rotor holder. Figure 39 shows a diagram of the rotor inserted into the rotor holder. Figure 40 shows another embodiment of the impeller. Figure 41 shows an enlarged view of the rotor holder. Figure 42 shows another embodiment of the rotation stop structure. Figure 43 shows another embodiment of the motor pump. Figure 44 shows another embodiment of the motor pump. Figure 45 shows an enlarged view of the first and second impellers of the series. Figure 46 shows another embodiment of the connection structure between the first impeller and the second impeller and the connecting shaft. Figure 47 shows another embodiment of the fastener. Figure 48 shows another embodiment of the second bearing. Figure 49 shows another embodiment of the second bearing. Figure 50 shows the side plate installed in the motor pump of the above embodiment. Figure 51 shows another embodiment of the side panel. Figure 52 shows another embodiment of the motor pump. Implementation

[0018] The following describes embodiments of the motor pump with reference to the drawings. In the following embodiments, the same or equivalent components are given the same symbols and repeated descriptions are omitted.

[0019] Figure 1 shows one embodiment of a motor pump. As shown in Figure 1, the motor pump MP includes: an impeller 1; an annular rotor 2 fixed to the impeller 1; a stator 3 disposed on the outer side of the rotor 2 in the radial direction; and a bearing 5 supporting the impeller 1. The impeller 1 has a flow path formed therein, and the bearing 5 is disposed on the outer side of the flow path (e.g., the inlet flow path) of the impeller 1.

[0020] In the embodiment shown in Figure 1, the motor pump MP is a rotating machine equipped with a permanent magnet motor, but the type of motor pump MP is not limited to this embodiment. In one embodiment, the motor pump MP may be equipped with an induction motor or a reluctance motor. When the motor pump MP is equipped with a permanent magnet motor, the rotor 2 is a permanent magnet. When the motor pump MP is equipped with an induction motor, the rotor 2 is a cage rotor.

[0021] In the embodiment shown in Figure 1, the impeller 1 is a centrifugal impeller. More specifically, the impeller 1 includes: a disc-shaped main plate 10; side plates 11, arranged opposite to the main plate 10; and multiple blades 12, arranged between the main plate 10 and the side plates 11. The motor pump MP, equipped with the impeller 1 as a centrifugal impeller, has superior pressure-generating characteristics compared to axial flow pumps or mixed flow pumps, and can generate high pressure. Furthermore, in this embodiment, the motor pump MP contributes to the rotational stability of the impeller 1 by utilizing the pressure difference generated within it.

[0022] The side plate 11 has a suction section 15 formed in its central portion and a body section 16 connected to the suction section 15. The suction section 15 extends in the direction of the centerline CL of the motor pump MP, and the body section 16 extends in a direction inclined relative to the centerline CL (more specifically, in a vertical direction). The centerline CL is parallel to the flow direction of the liquid (processing fluid) flowing due to the operation of the motor pump MP.

[0023] As shown in Figure 1, the side plate 11 has an annular protrusion 17 that extends from the outer edge 11a of the side plate 11 (more specifically, the end of the body portion 16) toward the suction portion 15. In the embodiment shown in Figure 1, the body portion 16 and the protrusion 17 are integral, but the protrusion 17 and the body portion 16 may also be separate components.

[0024] The rotor 2 has an inner diameter larger than the outer diameter of the protrusion 17 and is fixed to the outer peripheral surface 17a of the protrusion 17. The stator 3 is arranged to surround the rotor 2 and is housed in the stator housing 20. The stator housing 20 is located on the outer side of the impeller 1 in the radial direction.

[0025] The motor pump MP includes an intake housing 21 and an outlet housing 22 disposed on both sides of the stator housing 20. The intake housing 21 is disposed on the intake side of the impeller 1, and the outlet housing 22 is disposed on the outlet side of the impeller 1. The impeller 1, rotor 2, and bearing 5 are disposed on the inner side of the stator housing 20 in the radial direction, and are disposed between the intake housing 21 and the outlet housing 22.

[0026] The suction housing 21 has a suction port 21a in its central portion. The discharge housing 22 has a discharge port 22a in its central portion. These suction ports 21a and discharge ports 22a are arranged side by side along a centerline CL. Therefore, the treatment liquid drawn in from the suction port 21a and discharged from the discharge port 22a flows in a straight line.

[0027] As shown in Figure 1, with the stator housing 20 clamped between the suction housing 21 and the discharge housing 22, the operator inserts the through bolt 25 into the suction housing 21 and the discharge housing 22, and tightens the through bolt 25 to secure it. Thus, the motor pump (MP) assembly is complete.

[0028] When the motor pump MP is running, the treatment fluid is drawn in from the suction port 21a of the suction housing 21 (see the black arrow in Figure 1). The impeller 1, by rotating, pressurizes the treatment fluid, which flows inside the impeller 1 in a direction perpendicular to the centerline CL (i.e., the centrifugal direction). The treatment fluid discharged to the outside of the impeller 1 impacts the inner circumferential surface 20a of the stator housing 20, changing its direction. Then, the treatment fluid passes through the gap between the back of the impeller 1 (more specifically, the main plate 10) and the discharge housing 22, and is discharged from the discharge port 22a.

[0029] As shown in Figure 1, the motor pump MP includes return vanes 30 disposed on the back side of the impeller 1. In the embodiment shown in Figure 1, multiple return vanes 30 are provided, extending in a spiral shape. These multiple return vanes 30 are fixed to the discharge housing 22 and face the main plate 10 of the impeller 1. By providing the return vanes 30, the processed liquid discharged from the impeller 1 is smoothly guided to the discharge port 22a. The return vanes 30 help convert the velocity energy of the processed liquid discharged from the impeller 1 into pressure energy.

[0030] In the embodiment shown in Figure 1, the motor pump MP is divided into an intake side region Ra, an exhaust side region Rb, and an intermediate region Rc between the intake side region Ra and the exhaust side region Rb. The intake side region Ra is the region between the intake housing 21 (more specifically, the intake port 21a of the intake housing 21) and the impeller 1 (more specifically, the side plate 11 of the impeller 1). The exhaust side region Rb is the region between the exhaust housing 22 (more specifically, the exhaust port 22a of the exhaust housing 22) and the impeller 1 (more specifically, the main plate 10 of the impeller 1). The intermediate region Rc is equipped with multiple blades 12.

[0031] The rotor 2 and bearing 5 are disposed in the suction side region Ra of the impeller 1. In this embodiment, the impeller 1 has a conical side plate 11 extending from the suction side region Ra toward the discharge side region Rb. Therefore, a space (dead space) is formed in the suction side region Ra of the impeller 1. According to this embodiment, by disposing the rotor 2 and bearing 5 in the suction side region Ra, the motor pump MP has a structure that can effectively utilize the dead space, resulting in a compact structure.

[0032] The bearing 5 includes a rotating side bearing body 6 mounted on the protrusion 17 of the side plate 11 and a fixed side bearing body 7 mounted on the suction housing 21. The fixed side bearing body 7 is disposed on the suction side of the rotating side bearing body 6. The rotating side bearing body 6 is a rotating component that rotates together with the impeller 1, while the fixed side bearing body 7 is a stationary component that does not rotate even if the impeller 1 rotates.

[0033] The rotating bearing body 6 has a cylindrical portion 6a with an outer diameter smaller than the inner diameter of the protrusion 17, and a disc portion 6b protruding outward from the cylindrical portion 6a. Therefore, the cross-section of the rotating bearing body 6 has an L-shape. A sealing member (e.g., an O-ring) 31 is disposed between the inner circumferential surface 17b of the protrusion 17 and the cylindrical portion 6a.

[0034] The rotating side bearing body 6 is installed on the protrusion 17 of the impeller 1 with the sealing member 31 installed on the cylindrical part 6a. By installing the rotating side bearing body 6, the rotor 2 is arranged adjacent to the shaft disk part 6b of the rotating side bearing body 6.

[0035] The fixed-side bearing body 7 includes a cylindrical portion 7a facing the cylindrical portion 6a of the rotating-side bearing body 6, and a shaft disc portion 7b facing the shaft disc portion 6b of the rotating-side bearing body 6. The cross-section of the fixed-side bearing body 7 is the same as that of the rotating-side bearing body 6, and has an L-shape. Sealing members 32 and 33 are disposed between the cylindrical portion 7a of the fixed-side bearing body 7 and the suction housing 21. Although two sealing members 32 and 33 are disposed in this embodiment, the number of sealing members is not limited to this embodiment.

[0036] Figure 2 shows the flow of the treatment fluid through the gap between the rotating side bearing and the fixed side bearing. The treatment fluid is pressurized due to the rotation of impeller 1, therefore the pressure of the treatment fluid in the discharge side region Rb is greater than the pressure of the treatment fluid in the suction side region Ra. Consequently, a portion of the treatment fluid discharged from impeller 1 flows back to the suction side region Ra (see the black arrow in Figure 2).

[0037] More specifically, a part of the processing liquid flows through the gap between the stator housing 20 and the rotor 2 and into the gap between the disk portion 6b of the rotating-side bearing body 6 and the disk portion 7b of the fixed-side bearing body 7.

[0038] FIG. 3 is a diagram showing an embodiment of a plurality of grooves formed in the disk portion of the fixed-side bearing body. As shown in FIG. 3, the fixed-side bearing body 7 has a plurality of grooves 40 formed in the disk portion 7b. These plurality of grooves 40 are formed on the surface of the disk portion 7b facing the disk portion 6b of the rotating-side bearing body 6. The plurality of grooves 40 are formed to generate hydrodynamic pressure of the processing liquid in the gap between the disk portion 7b and the disk portion 6b. In this embodiment, the plurality of grooves 40 are spiral grooves extending spirally. In one embodiment, the plurality of grooves 40 are radial grooves extending radially. By forming the plurality of grooves 40, the bearing 5 can support the thrust load of the impeller 1 in a non-contact manner.

[0039] In the embodiment shown in FIG. 3, the plurality of grooves 40 are formed in the disk portion 7b, but in one embodiment, the plurality of grooves 40 may also be formed in the disk portion 6b of the rotating-side bearing body 6. By forming them in this way, the bearing 5 can support the thrust load of the impeller 1 in a non-contact manner.

[0040] FIG. 4A is a diagram showing an embodiment of a plurality of grooves formed in the cylindrical portion of the fixed-side bearing body. FIG. 4A shows the plurality of grooves 41 when viewed in the direction of the center line CL. The fixed-side bearing body 7 may also have a plurality of grooves 41 formed along the circumferential direction of the cylindrical portion 7a on the cylindrical portion 7a. In the embodiment shown in FIG. 4A, the plurality of grooves 41 are arranged at equal intervals, but they may also be arranged at non-uniform intervals.

[0041] These plurality of grooves 41 are formed on the surface of the cylindrical portion 7a facing the cylindrical portion 6a of the rotating-side bearing body 6 and extend parallel to the cylindrical portion 7a (i.e., in the direction of the center line CL). In the embodiment shown in FIG. 4A, when viewed in the direction of the center line CL, the plurality of grooves 41 each have a shape of an arc-shaped depression. The shape of the plurality of grooves 41 is not limited to this embodiment. In one embodiment, when viewed in the direction of the center line CL, the plurality of grooves 41 may each have a shape with a depression in the shape of the Chinese character '凹'.

[0042] Figures 4B and 4C show another embodiment of the groove formed on the cylindrical portion of the fixed-side bearing housing. As shown in Figures 4B and 4C, the fixed-side bearing housing 7 has an annular groove 42 formed on the cylindrical portion 7a along the circumferential direction. The groove 42 is formed on a part of the cylindrical portion 7a and has a U-shape when viewed from a direction perpendicular to the centerline CL (see Figures 4B and 4C). The cylindrical portions 7a are present at both ends 42a, 42a of the groove 42 in the centerline CL direction. With this structure, even if a radial load is applied to the impeller 1, the fixed-side bearing housing 7 (more specifically the cylindrical portion 7a) can reliably support the impeller 1 through the rotating-side bearing housing 6. In addition, the length of the groove 42 in the centerline CL direction is not particularly limited. In the embodiments shown in Figures 4B and 4C, the fixed-side bearing body 7 has a single groove 42. In another embodiment, the fixed-side bearing body 7 may also have multiple grooves 42 arranged along the centerline CL.

[0043] The processing fluid flowing through the gap between the shaft disc portion 6b and the shaft disc portion 7b flows into the gap between the cylindrical portion 6a and the cylindrical portion 7a. If the rotating side bearing housing 6 rotates together with the impeller 1, viscous resistance will be generated in the processing fluid flowing in this gap. There is a concern that this viscous resistance may adversely affect the operating efficiency of the motor pump MP.

[0044] As shown in the above embodiment, by forming multiple grooves 41 (or grooves 42), the size of the narrow area formed in the gap between the cylindrical portion 6a and the cylindrical portion 7a is reduced. Therefore, the viscous resistance generated in the processing fluid can be reduced. Furthermore, by forming multiple grooves 41 (or grooves 42), dynamic pressure of the processing fluid is generated, and the bearing 5 can support the radial load of the impeller 1 in a non-contact manner. The effect of reducing viscous resistance by reducing the size of the narrow area formed between the shaft disk portion 6b and the shaft disk portion 7b can also be achieved by providing multiple grooves 40 (see Figure 3).

[0045] In the embodiments shown in Figures 4A to 4C, grooves 41 and 42 are formed in the cylindrical portion 7a. However, in another embodiment, grooves 41 and 42 may also be formed in the cylindrical portion 6a of the rotating side bearing body 6. By forming them in this way, the bearing 5 can support the radial load of the impeller 1 in a non-contact manner.

[0046] As shown in Figure 2, the treatment fluid passing through the gap between the cylindrical portion 6a of the rotating side bearing 6 and the cylindrical portion 7a of the fixed side bearing 7 returns to the suction side of the motor pump MP through the gap between the side plate 11 of the impeller 1 and the suction housing 21. In this embodiment, the bearing 5 is positioned in the path of the treatment fluid leakage. With this configuration, a portion of the treatment fluid flows into the tiny gap between the rotating side bearing 6 and the fixed side bearing 7, thereby suppressing the leakage of the treatment fluid by the motor pump MP.

[0047] As described above, the pressure of the processing fluid in the discharge side region Rb is greater than the pressure of the processing fluid in the suction side region Ra. Therefore, the thrust load acts on the impeller 1 from the discharge port 22a of the discharge housing 22 toward the suction port 21a of the suction housing 21 (see the hollow arrow in Figure 1). The motor pump MP of this embodiment has a structure that reduces the thrust load.

[0048] Figure 5A shows one embodiment of the thrust load reduction structure located on the back side of the impeller. Figure 5B is a view of Figure 5A viewed from the arrow along line A. As shown in Figures 5A and 5B, the motor pump MP includes a thrust load reduction structure 45 located on the back side of the impeller 1 (more specifically, the main plate 10). In the embodiments shown in Figures 5A and 5B, the thrust load reduction structure 45 consists of a plurality of spirally extending back blades 46 mounted on the main plate 10. These plurality of back blades 46 can generate a load in the opposite direction to the thrust load by the rotation of the impeller 1. As a result, the thrust load reduction structure 45 can reduce the thrust load generated in the motor pump MP.

[0049] Figure 6 shows another embodiment of the thrust load reduction structure. As shown in Figure 6, the thrust load reduction structure 45 can also be a plurality of notches formed along the circumferential direction of the impeller 1 (more specifically, the main plate 10) and extending toward the center of the impeller 1. In the embodiment shown in Figure 6, a plurality of notches 47 are formed on the main plate 10 of the impeller 1. By forming a plurality of notches 47, the contact area between the processing fluid and the main plate 10 is reduced. As a result, the thrust load reduction structure 45 can reduce the thrust load generated in the motor pump MP. Although not shown in the figure, the embodiments shown in Figure 5 and Figure 6 can also be combined.

[0050] In this embodiment, the impeller 1 normally bears the thrust load from the discharge side to the suction side. Furthermore, the bearing 5 supports the impeller 1, which generates rotational force. Therefore, the impeller 1 body remains parallel, suppressing impeller sway. As a result, by using a structure that places only a single bearing 5 in the suction side region Ra (i.e., a single bearing structure), the motor pump MP can operate stably and continuously.

[0051] In one embodiment, at least one of the impeller 1 and bearing 5 may be made of a lightweight material. Examples of lightweight materials include resin or metals with low specific gravity (e.g., aluminum alloy, magnesium alloy, titanium alloy, etc.). This structure reduces the weight of the motor pump MP body and allows for further compaction of the bearing 5 (and impeller 1). Furthermore, the materials of components in contact with the liquid, such as the impeller 1 and bearing 5 (i.e., liquid-contacting components), are not particularly limited and can be appropriately changed to any material depending on the type of liquid.

[0052] Furthermore, in this embodiment, the plurality of return blades 30 (see Figure 1) can reduce the radial load generated in the impeller 1. The plurality of return blades 30 are arranged at equal intervals along the circumferential direction of the discharge port 22a. With such an arrangement, the radial load is evenly distributed, resulting in a reduction of the radial load generated in the impeller 1.

[0053] In this embodiment, the motor pump MP is equipped with a permanent magnet type motor. Therefore, when the motor pump MP starts, a predetermined load is applied to the bearing 5 to convert the repulsive force caused by the magnetic force into a rotational force. This load is a force generated in the rotor 2, and the bearing 5 supports this load.

[0054] Figures 7A and 7B show the rotors misaligned relative to the stator. As shown in Figure 7A, when the rotor 2 is misaligned relative to the stator 3 on the discharge side, the impeller 1 experiences a force from the rotating-side bearing 6 acting in the direction approaching the fixed-side bearing 7 due to the magnetic force generated between the rotor 2 and the stator 3 (refer to the arrows in Figure 7A). This configuration allows for adjustment (increase) of the thrust load acting on the rotating-side bearing 6 of the fixed-side bearing 7.

[0055] As shown in Figure 7B, when the rotor 2 is misaligned on the suction side relative to the stator 3, the impeller 1 is subjected to a force from the rotating side bearing 6 in the direction away from the fixed side bearing 7 due to the magnetic force generated between the rotor 2 and the stator 3 (see Figure 7B). With this configuration, the thrust load acting on the rotating side bearing 6 of the fixed side bearing 7 can be adjusted (reduced).

[0056] Figure 8 shows one embodiment of a bearing with a tapered structure. In the embodiment shown in Figure 8, the gap between the rotating side bearing body 6 and the fixed side bearing body 7 of the bearing 5 has a tapered structure extending from the suction side to the discharge side in a direction close to the centerline CL (i.e., the center portion of the impeller 1). As shown in Figure 8, the rotating side bearing body 6 and the fixed side bearing body 7 each have mutually opposing inclined surfaces 50 and 51. With this configuration, the radial load and thrust load acting on the rotating side bearing body 6 and the fixed side bearing body 7 can be concentrated on the inclined surfaces 50 and 51, and the bearing 5 can have a simple structure.

[0057] Figure 9 shows another embodiment of the bearing with a tapered structure. In the embodiment shown in Figure 9, the gap between the rotating side bearing body 6 and the fixed side bearing body 7 of the bearing 5 has a tapered structure extending from the suction side toward the discharge side in a direction away from the centerline CL (i.e., the center portion of the impeller 1). As shown in Figure 9, the rotating side bearing body 6 and the fixed side bearing body 7 each have mutually opposing inclined surfaces 53 and 54.

[0058] Figure 10 shows a pump unit equipped with multiple motor pumps. As shown in Figure 10, the pump unit PU may also include multiple motor pumps MP arranged in series and a converter 60 for controlling the operation of each of the multiple motor pumps MP. In the embodiment shown in Figure 10, the multiple motor pumps MP have the same structure as those shown in the above embodiment. Therefore, detailed descriptions of the motor pumps MP are omitted.

[0059] In the embodiment shown in Figure 10, the pump unit PU has three motor pumps MP, but the number of motor pumps MP is not limited to this embodiment. As described above, the suction port 21a and discharge port 22a of the pump unit PU are arranged side by side along the center line CL. Therefore, multiple motor pumps MP can be continuously arranged in a straight line, and the pump unit PU can easily have a multi-segment motor pump structure.

[0060] As shown in Figure 10, two intermediate housings 61 are arranged between the suction housing 21 adjacent to the impeller 1A of the first section and the discharge housing 22 adjacent to the impeller 1C of the third section. The impeller 1B of the second section is arranged between these intermediate housings 61 and 61. The intermediate housings 61 and 61 have a structure that is common to (or similar to) the suction housing 21. With the intermediate housings 61 and 61 sandwiched between the suction housing 21 and the discharge housing 22, the operator inserts the through bolts 25 into the suction housing 21, intermediate housings 61 and 61, and discharge housing 22 and tightens them to secure them, thereby assembling the pump unit.

[0061] As shown in Figure 10, a converter 60 is connected to the stator 3 of multiple motor pumps MP. The converter 60 can independently control each of the multiple motor pumps MP. Therefore, the operator can operate at least one motor pump MP at any time according to the operating conditions of the pump unit.

[0062] Figures 11 and 12 show another embodiment of the pumping unit. In the embodiment shown in Figures 11 and 12, the pumping unit PU has multiple motor pumps MP arranged in parallel. Although Figure 11 is simplified, these multiple motor pumps MP are respectively arranged inside the piping 65. Although Figure 11 shows 4 motor pumps MP, the number of motor pumps MP is not limited to this embodiment. As shown in Figure 12, 3 motor pumps MP can also be provided.

[0063] Figure 13A shows a motor pump as a comparative example. Figures 13B and 13C show another embodiment of the motor pump. As shown in Figure 13A, the motor pump as a comparative example has a rotating shaft RS, but the motor pump MP of this embodiment does not have a rotating shaft RS. Instead, the impeller 1 has a rounded protrusion 70 disposed at its center.

[0064] In the embodiment shown in Figure 13B, the impeller 1 has a protrusion 70A with a first radius of curvature. In the embodiment shown in Figure 13C, the impeller 1 has a protrusion 70B with a second radius of curvature different from the first radius of curvature. Hereinafter, protrusions 70A and 70B are sometimes referred to simply as protrusion 70 without distinction.

[0065] The protrusion 70 is disposed at the center of the main board 10 and is integral with the main board 10. In one embodiment, the protrusion 70 and the main board 10 may also be different components. In this case, the protrusion 70 with a different radius of curvature can be replaced according to the operating conditions of the motor pump.

[0066] The front end portion 71 of the protrusion 70 has a smooth convex shape, and the processing fluid flowing into the impeller 1 contacts the front end portion 71 of the protrusion 70. By providing the protrusion 70, the flow of the processing fluid is not obstructed and is smoothly and efficiently guided to the impeller 12. On the other hand, in the motor pump as a comparative example, the rotating shaft RS is fixed to the impeller by the nut Nt, so there is a concern that the flow of the processing fluid is obstructed by the nut Nt (and the rotating shaft RS).

[0067] The protrusion 70A shown in Figure 13B has a larger radius of curvature than the protrusion 70B shown in Figure 13C. By increasing the radius of curvature of the protrusion 70, the distance between the protrusion 70 and the side plate 11 decreases. Conversely, by decreasing the radius of curvature of the protrusion 70, the distance between the protrusion 70 and the side plate 11 increases. Thus, by changing the radius of curvature of the protrusion 70, the flow path size of the processing fluid in the impeller 1 can be adjusted. The flow path of the impeller 1 shown in Figure 13C is larger than that of the impeller 1 shown in Figure 13B.

[0068] According to this embodiment, since the motor pump MP does not have a rotating shaft, the number of parts can be reduced, and the size of the flow path can be adjusted. Furthermore, because there is no need to provide a rotating shaft, the impeller 1 can have a compact size. As a result, the overall size of the motor pump MP can be compact.

[0069] The motor pump causes impeller 1 to rotate at high speed. If the center of gravity of impeller 1 is off-center, impeller 1 will rotate at high speed in an eccentric state. This could result in noise, and in the worst case, motor pump failure.

[0070] Therefore, the operator performs a balancing (dynamic balancing) adjustment method to position the center of gravity of impeller 1 at the desired position. As shown in Figure 13A, if a rotating shaft RS is mounted on the impeller, the rotating shaft RS must be mounted on the testing machine, and the impeller and the rotating shaft RS must rotate together. In this embodiment, the rotating shaft RS is not mounted on impeller 1, so the operator can perform the balancing adjustment method described below.

[0071] Figures 14 to 18 illustrate one implementation of the balancing method. As shown in Figure 14, firstly, the operator performs the step of forming a through hole 10a at the center of the impeller 1 (more specifically, the main plate 10). Then, as shown in Figure 15, the operator inserts the shaft 76 of the balancing fixture 75 into the through hole 10a. The shaft 76 of the balancing fixture 75 is equivalent to a rotating shaft.

[0072] Next, as shown in Figure 16, the operator places the fixing body 77 on the back side of the impeller 1 and secures the shaft 76 to the fixing body 77. In this state, the operator determines the center of gravity position of the impeller 1 while rotating the impeller 1 together with the balancing fixture 75, and performs the step of adjusting the center of gravity position. Thus, the balancing fixture 75 has a structure that supports the center of the impeller 1. Therefore, the balancing fixture 75 is also called a center support adjustment fixture.

[0073] After the operator positions the center of gravity of the impeller 1 to the desired location, they remove the shaft 76 of the balancing fixture 75, and then insert the center cap 80 into the through hole 10a to close it (see Figures 17 and 18). The center cap 80, like the protrusion 70 in the embodiments shown in Figures 13B and 13C, has a rounded corner shape. Therefore, the flow of the treatment fluid is not obstructed and is smoothly and efficiently guided to the impeller 12.

[0074] Figure 19 shows another embodiment of the balancing fixture. In the embodiment shown in Figure 18, the balancing fixture 75 has a structure that supports the center of the impeller 1. In the embodiment shown in Figure 19, the balancing fixture 85 includes a support 86 that supports the rotating side bearing body 6 of the bearing 5, and a shaft portion 87 fixed to the support 86. Thus, the balancing fixture 85 has a structure that supports the end of the impeller 1. Therefore, the balancing fixture 85 is also called an edge support balancing fixture.

[0075] The support 86 is annular with an outer diameter smaller than the inner diameter of the rotating bearing body 6. By inserting the support 86 into the rotating bearing body 6, the balancing fixture 85 supports the impeller 1 through the rotating bearing body 6. In this state, the operator performs the step of rotating the impeller 1 together with the balancing fixture 85. Afterward, while the impeller 1 is rotating, the operator determines the center of gravity position of the impeller 1 and performs the step of adjusting the center of gravity position.

[0076] According to the embodiment shown in FIG19, the operator does not need to form a through hole 10a. In the embodiment shown in FIG19, the impeller 1 may also have a protrusion 70 formed at its center (see FIG13A and FIG13B).

[0077] Figure 20 shows another embodiment of the balance adjustment method. As shown in Figure 20, the rotor 2 has an annular iron core 2a and a plurality of magnets 2b embedded in the iron core 2a. The plurality of magnets 2b are arranged at equal intervals along the circumferential direction of the rotor 2 (more specifically the iron core 2a). The operator performs the step of forming a plurality of weight insertion holes 90 along the circumferential direction of the rotor 2. This step of forming weight insertion holes 90 is performed during the manufacture of the iron core 2a.

[0078] Weight insertion holes 90 are formed between adjacent magnets 2b. The operator performs the step of determining the center of gravity position of impeller 1, determining the current center of gravity position of impeller 1. If the center of gravity position of impeller 1 deviates, the operator inserts a weight 91 into at least one of the multiple weight insertion holes 90 to perform the step of adjusting the center of gravity position.

[0079] In one embodiment, if the center of gravity of impeller 1 deviates, the operator can remove the excessively heavy part that is the cause of the deviation and replace the weight 91 inserted into the weight insertion hole 90.

[0080] Figure 21A is a perspective view showing another embodiment of the pump unit. Figure 21B is a top view showing the pump unit shown in Figure 21A. As shown in Figures 21A and 21B, the pump unit PU includes multiple motor pumps (3 in this embodiment), a control device 100 that enables the multiple motor pumps MP to operate at variable speeds, and a current sensor 101 that is electrically connected to the control device 100 and detects the current supplied to the multiple motor pumps MP.

[0081] In this embodiment, two current sensors 101 are configured, but at least one current sensor 101 may also be configured. Examples of current sensors 101 include Hall elements and current converters (CTs).

[0082] The pump unit PU includes power lines 105 and signal lines 106 extending from the multiple motor pumps MP, a current sensor 101, and a protective sleeve 107 for the power lines 105 and the protection signal lines 106. The power lines 105 and signal lines 106 are electrically connected to the converter 60.

[0083] Copper rods (in other words, energizing plates, copper plates) 108 of phases U, V, and W span between multiple motor pumps MP, and a current sensor 101 is connected to one of these copper rods 108. Each motor pump MP has a terminal block 102, and the copper rods 108 are connected to the terminal block 102.

[0084] The control device 100 is electrically connected to the converter 60, and the control device 100 is configured to control the operation of the motor pump MP through the converter 60. The control device 100 can also be disposed outside the converter 60 or inside the converter 60.

[0085] The control device 100 includes a signal receiving unit 100a that receives signals from a current sensor 101 via a signal line 106, a storage unit 100b that stores information related to the operation of the motor pump MP and the operation program, and a control unit 100c that controls the operation of the motor pump MP based on the data received by the signal receiving unit and the data stored in the storage unit.

[0086] In this embodiment, the pump unit PU has one converter 60 for each of the multiple motor pumps MP. However, the pump unit PU may also have a number of converters 60 corresponding to the number of motor pumps MP. When multiple motor pumps MP are configured, the multiple converters 60 are controlled by the control device 100 to control the operation of each of the multiple motor pumps MP individually.

[0087] As described above, the motor pump MP has a compact structure that effectively utilizes unused space. Therefore, by connecting multiple motor pumps MP in series, the pump unit PU can operate at a high head without increasing the installation area.

[0088] The motor pump MP is a rotating machine equipped with a permanent magnet type motor. Such a motor rotates without control by forcibly applying voltage during startup. The inverter 60 controls the rotational speed of the motor pump MP in real time, after which the motor pump MP begins to operate at a constant speed.

[0089] In this embodiment, the pump unit PU has multiple motor pumps MP. Therefore, if the speed difference between the multiple motor pumps MP is eliminated before the speed of the motor pumps MP is controlled, there is no problem. However, if the speed difference is not eliminated, there is a concern that the motor pumps MP may not start properly.

[0090] Generally speaking, if the number of magnetic poles of rotor 2 increases, the motor pump MP will rotate smoothly, and the speed difference between multiple motor pumps MP can be easily eliminated. In this embodiment, the motor pump MP has a structure that forms a flow path inside rotor 2, and the outer diameter of rotor 2 is designed to be relatively large.

[0091] With a large outer diameter, the outer circumferential dimension of rotor 2 increases, allowing for easy configuration of multiple magnets and an increase in the number of magnetic poles. This configuration eliminates the speed difference between multiple motors pumping MP. Furthermore, in this embodiment, by using inexpensive planar magnets, the cost of rotor 2 can be reduced compared to conventional motors using bent magnets.

[0092] Furthermore, in this embodiment, the motor pump MP has a canned motor structure where the stator 3 is housed in the stator housing 20, and the distance between the rotor 2 and the stator 3 is greater than that of a typical motor. Therefore, the motor pump MP can reduce torque ripple, which represents the amplitude of torque variation, and as a result, the pump unit PU can eliminate the speed difference between multiple motor pump MPs.

[0093] In this way, the pump unit PU can eliminate the speed difference, and the motor pump MP can be expected to operate more stably during startup and / or constant operation.

[0094] Therefore, the control method of the motor pump MP is described below. In this embodiment, multiple motor pump MPs are connected in series. In this case, if the processing fluid contains foreign matter, the foreign matter may become stuck in the motor pump MP (especially the first motor pump MP), resulting in concerns that the foreign matter may obstruct the operation of the pump unit PU. Furthermore, there are also concerns that the difference in rotational speed between the multiple motor pump MPs may not be eliminated for certain reasons.

[0095] Figure 22 is a diagram showing the process of controlling the motor pump by the control device. As shown in step S101 of Figure 22, the control device 100, which is electrically connected to the converter 60, measures the current value of multiple motor pumps MP when the motor pump MP is currently running (more specifically, the sum of the current values ​​of each motor pump MP) based on the output current of the converter 60.

[0096] Subsequently, during normal operation of the motor pump MP (more specifically, during startup and constant operation), the control device 100 calculates a lower limit current value based on a preset predetermined current value, and compares the sum of the measured current values ​​(measured current value Amax) with the predetermined lower limit current value (refer to step S102). In one embodiment, the storage unit 100b of the control device 100 stores the predetermined current values ​​of each motor pump MP and the predetermined current values ​​of multiple motor pump MPs. The storage unit 100b can also calculate the predetermined current values ​​of multiple motor pump MPs from the predetermined current values ​​of each motor pump MP.

[0097] The control device 100 can also determine the "preset current value during normal operation" based on at least one of the rated current value and allowable current value of each motor pump MP, or it can determine the "preset current value during normal operation" based on the current value of multiple motor pump MP during operation.

[0098] In one embodiment, the control device 100 determines the lower limit current value based on the number of multiple motor pumps MP. For example, the lower limit current value is calculated using the following formula. Lower limit current value = Predetermined current value of multiple motor pumps MP × (1 - 1 / number of motor pumps n) In this embodiment, three motor pumps (MP) are configured, so the lower limit current value is 2 / 3 of the predetermined current value.

[0099] After step S102, the control device 100 compares the calculated lower limit current value with the measured current value (refer to step S103). More specifically, the control device 100 determines whether the measured current value is lower than the lower limit current value (measured current value Amax > lower limit current value).

[0100] If the measured current value is lower than the lower limit current value (refer to "Yes" in step S103), in this embodiment, if the measured current value is lower than 2 / 3 of the predetermined current value (i.e., the lower limit current value), the control device 100 determines that at least one of the multiple motor pumps MP has malfunctioned (refer to step S104). If the measured current value is not lower than the lower limit current value (refer to "No" in step S103), the control device 100 repeats steps S102 and S103.

[0101] If the control device 100 determines that an abnormal situation has occurred, the control device 100 may either continue to run the motor pump MP while issuing an alarm, or stop the operation of the motor pump MP and issue an alarm.

[0102] This control process can be implemented during the startup of the motor pump (MP) or during constant operation of the motor pump (MP). When the control process is implemented during the startup of the motor pump (MP), the measured current value is equivalent to the starting current value when multiple motor pumps (MP) are started, and the predetermined current value is equivalent to the preset current value when multiple motor pumps (MP) are started normally.

[0103] When the control process is performed while the motor pump MP is running at a constant speed, the measured current value is equivalent to the operating current value of multiple motor pump MPs during constant operation, and the predetermined current value is the preset current value of multiple motor pump MPs during normal constant operation.

[0104] The starting current value and the operating current value can be the same or different. Similarly, the preset current value during normal startup and the preset current value during normal constant operation can be the same or different.

[0105] In one embodiment, the control device 100 can also determine a predetermined current value based on the flow rate on the discharge side of the multiple motor pumps MP. In this case, the pump unit PU is equipped with a flow sensor (not shown in the figure) that detects the flow rate of the processed liquid, and the flow sensor is electrically connected to the control device 100.

[0106] The storage unit 100b of the control device 100 stores data showing the "correlation between the flow rate of the processing fluid during normal operation and the current supplied to multiple motor pumps MP during normal operation". The control device 100 determines a predetermined current value based on this data and calculates a lower limit current value based on the determined predetermined current value. The above formula can be cited as an example of a formula for calculating the lower limit current value.

[0107] The control device 100 compares the measured current value of multiple motor pumps MP with the lower limit current value when the measured current value is lower than the lower limit current value, and determines that at least one of the multiple motor pumps MP has malfunctioned.

[0108] In one embodiment, the control device 100 can also determine a predetermined current value based on the discharge side pressure of multiple motor pumps MP. In this case, the pump unit PU has a pressure sensor (not shown in the figure) that detects the pressure of the processing fluid, and the pressure sensor is electrically connected to the control device 100.

[0109] The storage unit 100b of the control device 100 stores data showing the "relationship between the pressure of the processing fluid and the current supplied to multiple motor pumps MP during normal operation". The control device 100 determines a predetermined current value based on this data and calculates a lower limit current value based on the determined predetermined current value. The above formula can be cited as an example of a formula for calculating the lower limit current value.

[0110] The control device 100 compares the measured current value of multiple motor pumps MP during constant operation with the lower limit current value. If the measured current value is lower than the lower limit current value, it determines that at least one of the multiple motor pumps MP has malfunctioned.

[0111] In the embodiments shown in Figures 21A and 21B, the pump unit PU includes a current sensor 101 (first current sensor 101) disposed between the first motor pump MP (first motor pump MP) and the second motor pump MP (second motor pump MP), and a current sensor 101 (second current sensor 101) disposed between the second motor pump MP and the third motor pump MP (third motor pump MP).

[0112] Therefore, the control device 100 can measure the current value of the first motor pump MP (i.e., the measured current value Aa1) based on the signal from the first current sensor 101, and measure the sum of the measured current value Aa1 of the first motor pump MP and the measured current value Aa2 of the second motor pump MP (i.e., the measured current value Ab(=Aa1+Aa2)) based on the signal from the second current sensor 101.

[0113] The control device 100 compares the measured current value Aa1 with the preset current value of each motor pump MP during normal operation (start-up, constant operation). If the measured current value Aa1 is lower than the preset current value (Aa1 < preset current value), it determines that the first motor pump MP is abnormal.

[0114] The control device 100 compares the measured current value Aa1 with the preset current value of each motor pump MP during normal operation (start-up and constant operation). If the measured current value Aa1 is greater than the preset current value (Aa1>preset current value) and the value obtained by subtracting the measured current value Aa1 from the measured current value Ab (i.e., Ab-Aa1) is less than the preset current value ((Ab-Aa1)<preset current value), it determines that the second motor pump MP has malfunctioned. The value obtained by subtracting the measured current value Aa1 from the measured current value Ab is equivalent to the measured current value Aa2.

[0115] If the control device 100 determines that the third motor pump MP is abnormal when it determines that the measured current value Amax is lower than the lower limit current value and the first motor pump MP and the second motor pump MP are not abnormal.

[0116] In the case where the pump unit PU has four motor pumps MP connected in series, the pump unit PU has a current sensor 101 (third current sensor 101) disposed between the third motor pump MP and the fourth motor pump MP (fourth motor pump MP).

[0117] The control device 100 can measure the sum of the measured current values ​​Aa1 of the first motor pump MP, Aa2 of the second motor pump MP, and Aa3 of the third motor pump MP (i.e., the measured current value Ac) based on the signal from the third current sensor 101.

[0118] The control device 100 determines that the third motor pump MP is malfunctioning when the measured current value Aa1 is greater than the predetermined current value (Aa1>predetermined current value), the value obtained by subtracting the measured current value Aa1 from the measured current value Ab (i.e., Ab-Aa1) is greater than the predetermined current value ((Ab-Aa1)>predetermined current value), and the value obtained by subtracting the measured current value Ab from the measured current value Ac (i.e., Ac-Ab, where Ab=Aa1+Aa2) is lower than the predetermined current value. The value obtained by subtracting the measured current value Ab from the measured current value Ac is equivalent to the predetermined current value Aa3.

[0119] If the control device 100 determines that the fourth motor pump MP is malfunctioning when it determines that the measured current value Amax is lower than the lower limit current value and that the first motor pump MP, the second motor pump MP, and the third motor pump MP are not malfunctioning, then the control device 100 determines that the fourth motor pump MP is malfunctioning. Furthermore, if the pump unit PU has five or more motor pump MPs connected in series, the control device 100 can also determine the malfunction of each motor pump MP using the same method described above.

[0120] The above embodiments illustrate a control method for multiple motor pumps MP connected in series, but the pump unit PU can also control multiple motor pumps MP connected in parallel. In the case of controlling multiple motor pumps MP connected in parallel (see Figures 11 and 12), the control device 100 can also be configured such that the starting times of each of the multiple motor pumps MP are staggered.

[0121] By staggering the start-up times, the pump unit PU can create a swirling flow within the piping 65. This swirling flow removes foreign matter and air adhering to the piping 65 and prevents the retention of the treatment fluid.

[0122] To create a swirling flow, the control device 100 can also start one of the multiple motor pumps MP (the first motor pump MP) after starting the first motor pump MP (the second motor pump MP). In this way, by continuously starting the adjacent motor pumps MP, a swirling flow that rotates along the starting sequence of the motor pumps MP can be formed in the pump unit PU.

[0123] For example, in the case of a configuration with 3 motor pumps MP, the control device 100 can start the 2nd motor pump MP after starting the 1st motor pump MP, or it can start the 1st motor pump MP adjacent to the 3rd motor pump MP after starting the 3rd motor pump MP.

[0124] Figure 23 shows another embodiment of the impeller. The bearing 5 is omitted in this embodiment. In the above embodiment, the impeller 1 has an annular protrusion 17 extending from the outer edge 11a of the side plate 11 toward the suction section 15 (see Figure 1). In the embodiment shown in Figure 23, the side plate 11 of the impeller 1 has an annular protrusion 117 disposed radially inside the outer edge 11a of the side plate 11.

[0125] The rotor 2 is disposed in an annular step portion formed between the outer edge 11a of the side plate 11 and the protrusion 117, and the exposed portion of the rotor 2 is covered by a protective layer 110. The protective layer 110 is one of the constituent components of the motor pump MP. Examples of the protective layer 110 include a corrosion-resistant shell, resin coating, or Ni-plated coating.

[0126] In one embodiment, the core 2a of the rotor 2 is joined to the protrusion 117 by means of adhesive, press-fitting, heat fitting, welding, etc. Similarly, the protective layer 110 is joined to the impeller 1 by means of adhesive, press-fitting, heat fitting, welding, etc.

[0127] Figure 24 shows another embodiment of the impeller. The bearing 5 is omitted in this embodiment. As shown in Figure 24, the impeller 1 may also have an annular mounting portion 118 disposed radially outside the protrusion 117. By inserting the rotor 2 into the annular space between the mounting portion 118 and the protrusion 117, the rotor 2 can be more securely fixed to the side plate 11. In this embodiment, the exposed portion of the rotor 2 is covered by a protective layer 110.

[0128] Figure 25 shows a sealing member disposed between the protective layer and the side plate. The bearing 5 is omitted in this embodiment. As shown in Figure 25, by disposing sealing members (e.g., O-rings) 120 and 121 between the protective layer 110 and the side plate 11 (more specifically, the outer edge 11a and protrusion 117 of the side plate 11), liquid contact with the rotor 2 can be reliably prevented.

[0129] The impeller 1 shown in Figures 1 to 25 is manufactured by means of casting, stainless steel stamping, or resin molding, for example. The impeller 1 shown in Figures 26 to 34 described below is the same and can also be manufactured by means of casting, stainless steel stamping, or resin molding.

[0130] Figure 26 shows another embodiment of the impeller. The bearing 5 is omitted in this embodiment. As shown in Figure 26, the rotor 2 is fixed to the outer edge 11a of the side plate 11 by stopping the flow path (i.e., the outlet flow path) of the impeller 1 formed between the main plate 10 and the side plate 11. In this embodiment, the rotor 2 is disposed in the suction side region Ra.

[0131] In the embodiment shown in Figure 26, the rotor 2 is not covered by the protective layer 110, and the rotor 2 is made of a corrosion-resistant material. In the above embodiment, the rotor 2 does not necessarily need to be covered by the protective layer 110, and may also be made of a corrosion-resistant material. In another embodiment, the rotor 2 may also be covered by the protective layer 110.

[0132] With this configuration, the processing fluid flowing through the outlet path impacts the inner circumferential surface of the rotor 2, changing the direction of the processing fluid. Then, the processing fluid is discharged from the outlet 22a through the gap between the main board 10 and the discharge housing 22.

[0133] In the embodiments shown in Figures 23 to 26, the rotor 2 and bearing 5 are arranged in the suction side region Ra of the impeller 1, thus the motor pump MP has a compact structure.

[0134] Figure 27 shows another embodiment of the motor pump. As shown in Figure 27, the motor pump MP includes a first impeller 1A disposed on the suction port 21a side, a second impeller 1B disposed on the discharge port 22a side, and a connecting shaft 126 connected to the first impeller 1A and the second impeller 1B. The rotor 2 is fixed to the first impeller 1A, and the stator 3 is disposed on the radially outer side of the rotor 2. The first impeller 1A is supported by a bearing 5, and the second impeller 1B is supported by the bearing 5 through the connecting shaft 126.

[0135] In the embodiment shown in Figure 27, the motor pump MP includes an intermediate housing 125 disposed between the first impeller 1A and the second impeller 1B. The intermediate housing 125 is an annular partition wall that separates the discharge side of the first impeller 1A from the suction side of the second impeller 1B. In this embodiment, the intermediate housing 125 is fixed to the stator housing 20.

[0136] In the embodiment shown in Figure 27, the motor pump MP has two impellers 1, but the number of impellers 1 is not limited to this embodiment. The motor pump MP may also have multiple intermediate housings 125 depending on the number of impellers 1. In other words, the motor pump MP may also have multiple impellers 1, including at least a first impeller 1A and a second impeller 1B.

[0137] Figure 28 shows another embodiment of the motor pump. As shown in Figure 28, the motor pump MP further includes a discharge-side bearing 128, which rotatably supports the connecting shaft 126 and is disposed on the discharge side of the second impeller 1B. The discharge-side bearing 128 is mounted on the discharge housing 22, and sealing members (e.g., O-rings) 127A and 127B are disposed in the gap between the discharge-side bearing 128 and the discharge housing 22. In addition, in the embodiment shown in Figure 28, the motor pump MP also has two impellers 1, but the number of impellers 1 is not limited to this embodiment. The motor pump MP may also have multiple impellers 1, including at least a first impeller 1A and a second impeller 1B.

[0138] As shown in Figure 28, the discharge housing 22 has a flow path 129 communicating with the discharge port 22a. The flow path 129 is located radially outside the connecting shaft 126. The treatment fluid discharged from the second impeller 1B is discharged to the outside through the flow path 129 and the discharge port 22a.

[0139] In the embodiment shown in Figure 28, the first impeller 1A and the second impeller 1B are supported not only by the bearing 5, but also by the discharge-side bearing 128. The discharge-side bearing 128 is a radial bearing. With this structure, radial displacement of the first impeller 1A and the second impeller 1B can be suppressed in the motor pump MP.

[0140] Figure 29 shows another embodiment of the motor pump. As shown in Figure 29, the motor pump MP may also have a connecting shaft 126 with an impeller 1 fixed thereon and a discharge side bearing 128 that rotatably supports the connecting shaft 126.

[0141] Figure 30 shows a motor pump with various components that can be selected according to operating conditions. In Figure 30, the horizontal axis represents flow rate, and the vertical axis represents head. As shown in Figure 30, the motor pump MP can be configured by selecting the optimal components according to various operating conditions (i.e., flow rate and head).

[0142] In the embodiment shown in Figure 30, the motor pump MP can be selected from a variety of different configurations (four in this embodiment) depending on the head and flow rate (see MPA~MPD in Figure 30). In this embodiment, the motor pump MP includes: multiple impellers 1 with different sizes; multiple rotors 2 fixed to the multiple impellers 1 and with different lengths; multiple stators 3 with lengths corresponding to the lengths of the multiple rotors 2; and multiple stator housings 20 that house the multiple stators 3 and have lengths corresponding to the lengths of the multiple stators 3.

[0143] The motor capacity of the motor pump MP is related to the length Lg of the stator 3. The head of the motor pump MP is related to the diameter D1 of the impeller 1. The flow rate of the motor pump MP is related to the size of the outlet flow path B2 of the impeller 1.

[0144] Multiple impellers 1 have multiple main plates 10, the diameter of which differs from that of multiple side plates 11 having the same diameter. In this specification, the diameter D1 of the impeller 1 is equivalent to the diameter of the main plate 10.

[0145] Explain the relationship between motor pumps MPA and MPB. As shown in Figure 30, motor pumps MPA and MPB have the same motor capacity (i.e., LgA = LgB). Motor pump MPA has a higher head capacity than motor pump MPB (i.e., D1A > D1B). Motor pump MPB has a higher flow capacity than motor pump MPA (i.e., B2B > B2A).

[0146] Explain the relationship between motor pumps MPA and MPC. MPC has a larger motor capacity than MPA (i.e., LgC > LgA). MPC has the same head capacity as MPA (i.e., D1A = D1C). MPC has a higher flow capacity than MPA (i.e., B2C > B2A).

[0147] Explain the relationship between motor pumps MPB and MPC. Motor pump MPC has a larger motor capacity than motor pump MPB (i.e., LgC > LgB). Motor pump MPC has a higher head capacity than motor pump MPB (i.e., D1C > D1B). The outlet flow path B2B of impeller 1 in motor pump MPB has the same or larger dimensions as the outlet flow path B2C of impeller 1 in motor pump MPC (i.e., B2B ≥ B2C).

[0148] Explain the relationship between motor pump MPC and motor pump MPD. Motor pump MPC has the same motor capacity as motor pump MPD (i.e., LgC = LgD). Motor pump MPC has a higher head capacity than motor pump MPD (i.e., D1C > D1D). Motor pump MPD has a higher flow capacity than motor pump MPC (i.e., B2D > B2C).

[0149] Explain the relationship between motor pumps MPB and MPD. Motor pump MPD has a larger motor capacity than motor pump MPB (i.e., LgD > LgB). Motor pump MPD has a higher flow capacity than motor pump MPB (i.e., B2D > B2B). Motor pump MPB has the same head capacity as motor pump MPD (i.e., D1B = D1D).

[0150] As shown in Figure 30, the inner diameter D2 and outer diameter D3 of the stator housing 20 are the same in all motor pumps (MP). Therefore, the operator can prepare components of different sizes in advance according to the head capacity and flow capacity, and then select the best component from multiple components based on the operating conditions of the motor pump (MP).

[0151] By making the inner diameter D2 and outer diameter D3 of the stator housing 20 the same, the pump unit PU can easily change its performance without changing the dimensions of components unrelated to head capacity and flow capacity (such as bearing 5, suction housing 21 and discharge housing 22).

[0152] Figure 31A is a cross-sectional view of another embodiment of the motor pump, and Figure 31B is a view of the motor pump shown in Figure 31A from the axial direction. As shown in Figures 31A and 31B, the motor pump MP may also have a vortex stop (in other words, a whirl stop) 130 disposed on the back side of the impeller 1.

[0153] The embodiment shown in Figure 31B includes one swirling stop 130, but at least one swirling stop 130 may also be provided. The swirling stop 130 is fixed to the discharge housing 22 and faces the main plate 10 of the impeller 1. The swirling stop 130 prevents the treatment fluid discharged from the impeller 1 from swirling between the impeller 1 and the discharge housing 22.

[0154] Figure 32A is a cross-sectional view of another embodiment of the motor pump, and Figure 32B is a front view of the suction housing of the motor pump shown in Figure 32A. As shown in Figures 32A and 32B, the motor pump MP has a suction housing 141 and a discharge housing 142 with a flat, disc-shaped shaft.

[0155] In the above embodiments, the intake port 21a of the intake housing 21 protrudes from the outer surface of the intake housing 21, and similarly, the discharge port 22a of the discharge housing 22 protrudes from the outer surface of the discharge housing 22. In this embodiment, the intake housing 141 has a flat disc shape, therefore the intake port 141a is formed on the same plane as the outer surface of the intake housing 141. Similarly, because the discharge housing 142 has a flat disc shape, the discharge port 142a is formed on the same plane as the outer surface of the discharge housing 142.

[0156] With this structure, the connecting pipe 140, which is connected to the motor pump MP, can be directly connected to the suction housing 141. Although not shown in the figure, the connecting pipe 140 can also be directly connected to the discharge housing 142, which has a flat disc shape.

[0157] With this configuration, there is no need to configure a component (connecting structure) to connect the connecting pipe 140 and the suction housing 141, which reduces the number of parts used to connect the piping (not shown in the figure) to the motor pump MP.

[0158] Connecting components are expected to leak, so by eliminating connecting components, leakage can be reliably prevented. In this embodiment, although not shown in the figure, a sealing component (such as an O-ring or gasket) is provided between the connecting pipe 140 and the suction housing 141.

[0159] An insertion hole 141b is formed on the radially outer side of the suction port 141a of the suction housing 141, for inserting a fastener 150 that secures the connecting pipe 140 to the suction housing 141. The connecting pipe 140 has a through hole 140a communicating with the insertion hole 141b. By inserting the fastener 150 into the through hole 140a and the insertion hole 141b, the operator can secure the connecting pipe 140 and the suction housing 141 together.

[0160] A bolt receiving portion 142b is formed on the outer radial side of the discharge port 142a of the discharge housing 142 to accommodate the head 25a of the through bolt 25. By accommodating the head 25a of the through bolt 25 in the bolt receiving portion 142b, the head 25a can be prevented from protruding from the discharge housing 22.

[0161] In one embodiment, the intake housing 141 may also have a bolt receiving portion corresponding to the bolt receiving portion 142b. That is, at least one of the intake housing 141 and the discharge housing 142 has a bolt receiving portion for accommodating the head 25a of the through bolt 25.

[0162] Figure 33 shows a pump unit with motor pumps connected in series. As shown in Figure 33, the motor pump MP shown in Figures 32A and 32B has a suction housing 141 and a discharge housing 142 with a flat, disc-shaped shaft, so that the suction housing 141 and discharge housing 142 arranged adjacent to each other can make surface contact with each other. The suction housing 141 and discharge housing 142 that make surface contact with each other are equivalent to an intermediate housing.

[0163] Although not shown in the figure, a sealing member (such as an O-ring or gasket) is also provided between the suction housing 141 and the discharge housing 142, which are in surface contact with each other.

[0164] According to this embodiment, there is no need to configure an intermediate housing 61 (see Figure 10). A pump unit PU with multiple motor pumps MP can be formed by simply connecting multiple motor pumps MP in series with the same structure.

[0165] The motor pump MP of this embodiment has simple main components (i.e., impeller 1, rotor 2, stator 3, and bearing 5), achieving a small size and lightweight design. Therefore, multiple motor pump MPs arranged in series can be easily fastened together by using through bolts 25.

[0166] Furthermore, by making the suction housing 141 and the discharge housing 142 in surface contact with each other, the thermal conductivity of the pump unit PU can be improved, and temperature balance can be achieved among multiple motor pumps MP. As a result, the pump unit PU can operate at a constant speed.

[0167] Figure 34 shows another embodiment of the impeller. In the above embodiment, the impeller 1 is a centrifugal impeller. More specifically, the impeller 1 has a main plate 10 extending perpendicularly to the centerline CL, and the liquid pressurized by the impeller 1 is discharged perpendicularly relative to the centerline CL. In the embodiment shown in Figure 34, the impeller 1 is a diagonal flow impeller. More specifically, the impeller 1 has a main plate 160 inclined at a predetermined angle relative to the centerline CL. The main plate 160 is inclined from the suction side to the discharge side, and the liquid pressurized by the impeller 1 is discharged to the outside of the direction inclined relative to the centerline CL.

[0168] Figure 35 shows another embodiment of the motor pump. As shown in Figure 35, the motor pump MP includes: a rotor holder 200 for holding the rotor 2; and an impeller 1, which is a press-formed product, with the rotor holder 200 fixed to the impeller 1. In this embodiment, the rotor 2 and the bearing 5 are disposed in the suction side region of the impeller 1 (see Figure 1).

[0169] The impeller 1 includes a main plate 10, side plates 11, and multiple blades 12. These main plates 10, side plates 11, and blades 12 are stamped products made of a metal material with excellent ductility. Stainless steel is an example of such a metal material. In one embodiment, the main plates 10, side plates 11, and blades 12 are each individually stamped and then joined together after forming.

[0170] By constructing the impeller 1 using a stamped part, the overall weight reduction of the impeller 1 can be achieved. This weight reduction of the impeller 1 helps to reduce (or eliminate) the balancing (dynamic balancing) adjustment that positions the center of gravity of the impeller 1 at the desired location. Furthermore, this configuration allows for a reduction in the distance between the main plate 10 and the side plate 11, resulting in further compactness of the motor pump MP.

[0171] The rotor holder 200 prevents corrosion of the rotor 2 due to contact with the processing fluid. The rotor holder 200 includes: an annular receiving portion 201, formed by stamping, for accommodating the rotor 2; and an annular cover plate 202 for closing the receiving portion 201. The receiving portion 201 has an annular U-shape, concentrically positioned with respect to the centerline CL, and is aligned with the impeller 1. For example, the receiving portion 201 can also be manufactured by deep drawing.

[0172] The receiving portion 201 is fixed (joined) to the side plate 11 of the impeller 1. In one embodiment, the receiving portion 201 is fused to the side plate 11. In order to easily fix the receiving portion 201 to the impeller 1, the impeller 1 and the receiving portion 201 are preferably made of the same material.

[0173] Figure 36 is an enlarged view of the rotor holder. As shown in Figure 36, in order to prevent the processing fluid from seeping into the gap between the receiving portion 201 and the cover plate 202, the rotor holder 200 includes a sealing member (e.g., an O-ring) 205 disposed between the receiving portion 201 and the cover plate 202. The sealing member 205 secures the cover plate 202 to the receiving portion 201 by its elastic force.

[0174] In one embodiment, the cover plate 202 can also be inserted into the rotor holder 200 by a mechanical insertion method. One example of this mechanical insertion method is pressing the cover plate 202 into the rotor holder 200. Another example is inserting the cover plate 202 into the thermally expanded rotor holder 200 after heating it (a shrink fit). In this case, to reduce the thermal impact on the magnetic force of the rotor 2 (i.e., thermal demagnetization), it is desirable to magnetize the rotor 2 after inserting the cover plate 202 into the rotor holder 200. Another example of this mechanical insertion method is inserting the cover plate 202 into the rotor holder 200 using a cold fit. Yet another example is inserting the cover plate 202 into the rotor holder 200 using an adhesive.

[0175] The receiving portion 201 of the rotor holder 200 includes: an outer annular portion 231; an inner annular portion 232 disposed inside the outer annular portion 231 in the radial direction; and an annular back portion 233 connecting the outer annular portion 231 and the inner annular portion 232.

[0176] The rotating side bearing body 6 is mounted on the rotor holder 200, and the fixed side bearing body 7 is disposed on the suction side of the rotating side bearing body 6 (see Figure 35). Sealing members 31A and 31B are disposed between the inner annular portion 232 and the cylindrical portion 6a of the rotating side bearing body 6. In this embodiment, two sealing members are disposed, but the number of sealing members is not limited to this embodiment.

[0177] In order to seal the sealing members 31A and 31B within the inner annular portion 232, the inner annular portion 232 is machined into a smooth shape during the stamping process of the rotor holder 200. Thus, by performing the stamping process, the additional step required to seal the sealing members 31A and 31B within the inner annular portion 232 can be omitted.

[0178] The receiving portion 201 (more specifically, the outer annular portion 231 and the inner annular portion 232) extends parallel to the cylindrical portion 6a of the rotating side bearing body 6, and the cylindrical portion 6a is disposed inside the inner annular portion 232 of the rotor holder 200 in the radial direction. The shaft disc portion 6b of the rotating side bearing body 6 extends parallel to the cover plate 202 and is disposed adjacent to the cover plate 202.

[0179] If air is present inside the receiving portion 201, there is a concern that the expansion of the air inside the receiving portion 201 may cause the cover plate 202 to move away from the receiving portion 201. In this embodiment, the shaft disc portion 6b of the rotating side bearing body 6 adjacent to the cover plate 202 can restrict the movement of the cover plate 202.

[0180] In one embodiment, in order to reduce the amount of air expansion in the receiving part 201, the rotor holder 200 may also be equipped with a filler (e.g., lubricating grease, potting material, adhesive, etc.) filled in the receiving part 201.

[0181] The receiving portion 201 includes: an outer surface 201a that contacts the rotating side bearing body 6; an inner surface 201b that contacts the rotor 2; and a corner surface 201c formed at the corner of the inner surface 201b. As described above, since the rotor holder 200 is a stamped product, the corner surface 201c is a smooth curved surface. On the other hand, the rotor 2 is manufactured by overlapping laminated core materials, which are blanks from stamped and sheared iron sheets, so the rotor 2 has sharp corners.

[0182] Therefore, even when the rotor 2 is inserted into the receiving part 201, the sharp corners of the rotor 2 will contact the smooth corner surface 201c, causing the rotor 2 to not be able to fit completely into the back part 233. As a result, the operator cannot reliably position the rotor 2 relative to the rotor holder 200, and there is a concern that the rotor 2 cannot be stably accommodated in the rotor holder 200.

[0183] Therefore, the rotor holder 200 includes a spacer 203 disposed between the receiving portion 201 and the rotor 2. In the embodiment shown in FIG36, the spacer 203 is a precision adjustment plate disposed between the back portion 233 and the rotor 2. By disposing of the spacer 203, the rotor 2 is prevented from contacting the corner surface 201c. As a result, the rotor 2 and the spacer 203 are closely fitted and accommodated in the rotor holder 200, so the operator can reliably position the rotor 2 relative to the rotor holder 200. With this configuration, the operator can stably accommodate the rotor 2 in the rotor holder 200.

[0184] Figure 37 shows another embodiment of the spacer. As shown in Figure 37, the rotor holder 200 may also include a spacer 210 disposed between the receiving portion 201 and the rotor 2. In the embodiment shown in Figure 37, the spacer 210 is a protrusion extending from the back portion 233 of the rotor holder 200.

[0185] Methods for securing the rotor 2 to the rotor holder 200 include, for example, fastening with an adhesive, fastening with a heat-shrink fitting, and fastening with a cold-shrink fitting. When using a fastening method that adapts to the temperature changes of the rotor 2 and / or the rotor holder 200 (e.g., heat-shrink fitting or cold-shrink fitting), the dimensions of the rotor 2 and the rotor holder 200 must be appropriately determined. Therefore, as a simple fastening method, a fastening method at room temperature is preferred.

[0186] Figure 38 shows the rotor inserted into the rotor holder. As shown in Figure 38, the inner surface 230 of the rotor 2, which contacts the inner annular portion 232, has a polygonal shape (an octagon in this embodiment). Because the inner surface 230 of the rotor 2 has a polygonal shape, when the rotor 2 is inserted into the rotor holder 200 at room temperature, the inner annular portion 232 of the rotor holder 200 can make linear contact with the inner surface 230 of the rotor 2.

[0187] This contact prevents the rotor 2 from making full contact with the inner annular portion 232 of the rotor holder 200. Therefore, even if the rotor 2 is pressed into the rotor holder 200, the contact area between the rotor 2 and the rotor holder 200 can be reduced, thus preventing deformation of the rotor holder 200.

[0188] Figure 39 shows the rotor inserted into the rotor holder. As shown in Figure 39, the inner annular portion 232 may also have multiple protrusions 235, which form contact areas with the rotor 2. The protrusions 235 of the inner annular portion 232 face the inner surface 230 of the rotor 2, and the rotor 2 contacts the protrusions 235. With this configuration, the contact area between the rotor 2 and the rotor holder 200 can be reduced, thereby preventing deformation of the rotor holder 200.

[0189] Returning to Figure 35, the motor pump MP has a stator housing 20 that houses the stator 3, and is integrally formed with the stator 3 by resin molding. As shown in Figure 35, the stator 3 includes a stator core 3a and a coil 3b wound around the stator core 3a with an insulating material 220 in between. Examples of the insulating material 220 include insulating paper, resin, etc. The resin constituting the stator housing 20 is insulating and is made of a material with excellent thermal conductivity (the same material as the filler material).

[0190] The motor pump MP includes a motor frame 221, which covers the outer peripheral surface of the stator housing 20 and contacts the stator 3. The motor frame 221 has through holes 242 through which power lines 105 and signal lines 106 extending from the coil 3b pass. The motor frame 221 is made of a material with excellent thermal conductivity (e.g., a metal). Thus, the stator 3 is covered by the thermally conductive stator housing 20 and contacts the thermally conductive motor frame 221. Therefore, heat emitted from the coil 3b of the stator 3 is released to the outside through the stator housing 20 and the motor frame 221.

[0191] A sealing member (e.g., an O-ring) 241 is provided between the suction housing 21 and the discharge housing 22 and the stator housing 20 to prevent the treatment fluid from leaking to the outside. The stator housing 20 has a sealing groove 229 in which the sealing member 241 is installed.

[0192] The stator housing 20 is formed by injecting resin into a mold. By pre-forming protrusions corresponding to the sealing groove 229 in the mold, the step of separately forming the sealing groove 229 after manufacturing the stator housing 20 can be omitted. In one embodiment, sealing grooves for mounting sealing members 241 can also be formed on the intake housing 21 and the discharge housing 22 (not shown in the figure).

[0193] In this embodiment, the stator housing 20, the return blade 30, and the partition plate 240 fixed to the return blade 30 are integrally molded components manufactured by resin molding. The return blade 30 sometimes has a non-linear shape characteristic of flow paths. According to this embodiment, by using resin molding where resin is injected into a mold, the stator housing 20, the return blade 30, and the partition plate 240 can be easily mass-produced in an integral molding manner.

[0194] In one embodiment, to improve heat dissipation from the coil 3b, the stator housing 20 may also be covered with the stator core 3a and the coil 3b covered with filler material. Thus, by covering the coil 3b with filler material, the filler material enters between the wires constituting the coil 3b, thereby improving the heat dissipation of the coil 3b. In this state, further coating the stator core 3a and the coil 3b with the resin constituting the stator housing 20 can further improve the heat dissipation of the stator 3.

[0195] Examples of resins constituting the stator housing 20 include two-component curing resins (e.g., dicyclopentadiene resin) or heat-curing resins (e.g., epoxy resin) that exhibit excellent flowability at room temperature. In one embodiment, the strength of the stator housing 20 can be improved by incorporating fibers as additives into the resin. In another embodiment, the thermal conductivity of the stator housing 20 can be improved by incorporating a material with high thermal conductivity as an additive. Alternatively, both fibers and high thermal conductivity materials can be used as additives and incorporated into the resin constituting the stator housing 20.

[0196] Figure 40 shows another embodiment of the impeller. As shown in Figure 40, the motor pump MP includes an impeller 1, which is a resin molded article integrally formed with a rotor holder 200. The impeller 1 is integrally formed from a main plate 10, side plates 11, and blades 12, and is made of resin. In one embodiment, the strength of the impeller 1 can be improved by incorporating fibers as an additive into the resin.

[0197] The rotor holder 200 includes: an annular receiving portion 251, which is molded from resin and accommodates the rotor 2; and an annular holder 252, which closes the receiving portion 251. The impeller 1 and the receiving portion 251 of the rotor holder 200 are integrally formed and are made of resin.

[0198] The annular retainer 252 is made of a corrosion-resistant material (such as stainless steel) formed by stamping. The annular retainer 252 and the rotor 2 are fastened by mechanical methods such as heat fitting, cold fitting, and pressing. In one embodiment, the annular retainer 252 and the rotor 2 are fastened to each other by an adhesive.

[0199] When the rotor 2 is fastened to the annular retainer 252, in order to reduce the pressure load on the rotor 2, the inner surface 230 of the rotor 2 that contacts the annular retainer 252 may also be polygonal (see Figure 38). The annular retainer 252 may also have a plurality of protrusions 235, which form contact portions that contact the rotor 2 (see Figure 39).

[0200] Figure 41 is an enlarged view of the rotor holder. As shown in Figure 41, the annular holder 252 includes: a ring portion 253 having an L-shaped cross-section; and a bent portion 254 that bends from the ring portion 253. The ring portion 253 of the annular holder 252, which is a stamped product, has a smooth corner surface 257 formed on its bent portion.

[0201] In this embodiment, the rotor 2 and bearing 5 are also disposed in the suction side region of the impeller 1 (see Figure 1). The rotating side bearing body 6 is mounted on the annular retainer 252, and the fixed side bearing body 7 is disposed on the suction side of the rotating side bearing body 6. Sealing members 31A and 31B are disposed between the annular portion 253 of the annular retainer 252 and the cylindrical portion 6a of the rotating side bearing body 6. In this embodiment, the annular portion 253 is also stamped, so the additional step of making the sealing members 31A and 31B fit tightly into the annular portion 253 can be omitted.

[0202] As described above, rotor 2 has sharp corners. Therefore, when rotor 2 is mounted on an annular holder 252, the sharp corners of rotor 2 will also come into contact with the smooth corner surface 257, resulting in concerns that the operator may not be able to stably accommodate rotor 2 in rotor holder 200.

[0203] Therefore, the rotor holder 200 includes a spacer 260 disposed between the annular holder 252 and the rotor 2. In the embodiment shown in FIG41, the spacer 260 is a thin plate for precision adjustment disposed between the annular holder 252 and the rotor 2. In another embodiment, the spacer 260 may also be a protrusion (not shown in the figure) protruding from the annular holder 252 (see FIG37).

[0204] When manufacturing the rotor holder 200, resin is injected into the mold while the annular holder 252 and the rotor 2 mounted on the annular holder 252 are placed in the mold. By this manufacturing method, the resin constituting the receiving portion 251 of the rotor holder 200 encapsulates the rotor 2, and as a result, the receiving portion 251 seals the rotor 2.

[0205] The resin injected into the mold is at a high temperature. Therefore, if the high-temperature resin comes into contact with the rotor 2 mounted on the annular holder 252, the rotor 2 will undergo thermal demagnetization. Therefore, the rotor 2 must be magnetized after the rotor holder 200 is manufactured.

[0206] In this embodiment, the receiving portion 251 of the rotor holder 200 and the impeller 1 are integrally molded components manufactured by resin molding. The impeller 1, like the return blade 30, sometimes has a non-linear shape characteristic of a flow path. According to this embodiment, by employing resin molding where resin is injected into a mold, the receiving portion 251 of the rotor holder 200 and the impeller 1 can be easily mass-produced in an integral molding manner.

[0207] The annular retainer 252 has a rotation stop structure, which forms a connection point with the receiving portion 251. Through the operation of the motor pump MP, the torque of the rotor 2 is transmitted to the impeller 1. Because the annular retainer 252 has a rotation stop structure, even if the impeller 1 rotates, the annular retainer 252 will not rotate relative to the receiving portion 251. The specific configuration of the rotation stop structure is described below.

[0208] As shown in Figure 41, the receiving portion 251 includes a body portion 255 that surrounds most of the rotor 2, and a bent portion 256 formed by bending the body portion 255. The annular portion 253 of the annular retainer 252 has an insertion hole 253a in which a portion of the receiving portion 251 (more specifically, the bent portion 256) is embedded. Multiple insertion holes 253a are formed along the circumferential direction of the annular retainer 252.

[0209] The annular retainer 252 and the receiving portion 251 are strongly fastened together by embedding a portion of the bent portion 256 into the embedment hole 253a. This embedding can be performed by injecting resin into the mold during the manufacture of the rotor retainer 200.

[0210] Similarly, the bent portion 254 of the annular retainer 252 has an insertion hole 254a into which a portion of the body portion 255 of the receiving portion 251 is embedded. Multiple insertion holes 254a are formed along the circumferential direction of the annular retainer 252. By embedding a portion of the body portion 255 into the insertion hole 254a, the annular retainer 252 and the receiving portion 251 are strongly fastened together. This embedding can be performed by injecting resin into a mold during the manufacture of the rotor retainer 200. According to this embodiment, the rotor retainer 200 can be mechanically prevented from peeling off from the rotor 2 due to the difference in linear expansion between the rotor 2 and the rotor retainer 200 caused by temperature changes.

[0211] Figure 42 shows another embodiment of the rotation stop structure. As shown in Figure 42, the rotation stop structure can also be a U-shaped bent portion 253b, 254b. More specifically, the annular retainer 252 has an annular portion 253b bent into a U-shape, and similarly, the bent portion 254 has an annular portion 254b bent into a U-shape. With this structure, the annular retainer 252 and the receiving portion 251 are strongly fastened together. Alternatively, the embodiment shown in Figure 41 can be combined with the embodiment shown in Figure 42.

[0212] In one embodiment, the rotation stop structure may also be a gear-shaped cut (not shown in the figure) formed on the ring portion 253 and the bent portion 254 respectively. Multiple such cuts are formed along the circumferential direction of the annular retainer 252.

[0213] In one embodiment, in order to improve the fit between the receiving part 251 and the annular retainer 252, a primer can be applied to the surface of the annular retainer 252 in advance to perform a primer treatment to remove oxides from the surface of the annular retainer 252.

[0214] In the embodiments shown in Figures 40 to 42, the stator housing 20 also has the same structure as the stator housing 20 in the embodiments shown in Figures 35 to 39. More specifically, the motor pump MP includes: a stator housing 20 that houses the stator 3 and is integrally formed with the stator 3 by resin molding; and a motor frame 221 that covers the outer peripheral surface of the stator housing 20 and contacts the stator 3.

[0215] Figure 43 shows another embodiment of the motor pump. In this embodiment, the same symbols are used for the same or equivalent components as in the above embodiments, and repeated descriptions are omitted.

[0216] As shown in Figure 43, the motor pump MP includes multiple impellers 1, including at least a first impeller 1A disposed on the suction port 21a side and a second impeller 1B disposed on the discharge port 22a side. In one embodiment, at least one impeller 1 may also be disposed between the first impeller 1A and the second impeller 1B. The rotor holder 200 holding the rotor 2 is fixed to the first impeller 1A, and a stator 3 is disposed on the outer side of the rotor 2 in the radial direction and accommodated in the resin stator housing 20.

[0217] As shown in Figure 43, the rotor 2, housed in the rotor holder 200, is fixed to the first impeller 1A. Therefore, the rotational force of the rotor 2 acts on the first impeller 1A. The rotational force acting on the first impeller 1A is transmitted to the second impeller 1B through the connecting shaft 270. Thus, the first impeller 1A bears the entire rotational force of the rotor 2, resulting in a larger load on the first impeller 1A and raising concerns about the possibility of damage to the first impeller 1A.

[0218] Therefore, the first impeller 1A is expected to have higher strength than the other impellers 1 (the second impeller 1B in this embodiment). Furthermore, in order to achieve the high head of the motor pump MP of this embodiment, the first impeller 1A is expected to have high strength. Thus, the motor pump MP, which has multiple impellers 1, is expected to have both a compact structure and a high-strength structure. With such a structure, the motor pump MP can operate at a constant speed.

[0219] Therefore, the motor pump MP of this embodiment not only has a compact structure, but also a structure capable of constant operation. The structure of the motor pump MP is described below with reference to the drawings.

[0220] The first impeller 1A is supported by the first bearing 5 and is connected to the connecting shaft 270. The second impeller 1B is also connected to the connecting shaft 270. The motor pump MP has an intermediate housing 275 disposed between the first impeller 1A and the second impeller 1B, and a liner ring 276 is connected to the intermediate housing 275. The liner ring 276 is a ring member that suppresses the backflow of the processing fluid sucked into the second impeller 1B.

[0221] In the embodiment shown in Figure 43, the intermediate housing 275 is composed of a component separate from the stator housing 20, but the intermediate housing 275 and the stator housing 20 can also be composed of the same component. In this embodiment, the return blade 30 fixed to the intermediate housing 275 also serves as a guide blade to guide the processing liquid discharged from the first impeller 1A to the second impeller 1B. The return blade (and guide blade) 30 can efficiently convert the flow rate of the processing liquid generated by the centrifugal force of the first impeller 1A into pressure and guide it to the liquid inlet of the first impeller 1B.

[0222] The ejector housing 22 is integrally formed with the return blade 30 and the partition 245 fixed to the return blade 30. That is, the ejector housing 22, the return blade 30, and the partition 245 are integrally formed components. These integrally formed ejector housing 22, return blade 30, and partition 245 can also be integrally formed by resin molding. In one embodiment, the ejector housing 22, return blade 30, and partition 245 can also be separate components. The return blade 30 fixed to the ejector housing 22 also performs the same function as the return blade 30 fixed to the intermediate housing 275.

[0223] Figure 44 shows another embodiment of the motor pump. In the embodiment shown in Figure 43, the rotor holder 200 has the same structure as the rotor holder 200 in the embodiment shown in Figure 35. As shown in Figure 44, the rotor holder 200 may also have the same structure as the rotor holder 200 in the embodiment shown in Figure 40.

[0224] Figure 45 shows an enlarged view of the first impeller and the second impeller. As shown in Figure 45, the hub 281 of the first impeller 1A has a larger size than the hub 282 of the second impeller 1B. Hub 281 is the part where the first impeller 1A connects to the connecting shaft 270, and hub 282 is the part where the second impeller 1B connects to the connecting shaft 270.

[0225] In the embodiment shown in Figure 45, the length L1 of the centerline CL of hub 281 is longer than the length L2 of the centerline CL of hub 282. As described above, with the rotation of rotor 2, the load acting on the first impeller 1A is greater than the load acting on the second impeller 1B. According to this embodiment, because the hub 281 of the first impeller 1A has a larger size than the hub 282 of the second impeller 1B, the first impeller 1A can sufficiently withstand the rotational force of rotor 2. As a result, damage to the first impeller 1A can be prevented in the motor pump MP.

[0226] As shown in Figure 45, the motor pump MP includes a sleeve 280 that forms a predetermined distance between the first impeller 1A and the second impeller 1B. The sleeve 280 is disposed between the first impeller 1A and the second impeller 1B. By configuring the sleeve 280, the operator can easily manage the distance between the first impeller 1A and the second impeller 1B.

[0227] The first impeller 1A and the second impeller 1B each have a transmission structure (key structure, double chamfer structure, bolt groove structure, etc.), which are connected to the connecting shaft 270 by means of such a structure.

[0228] In this embodiment, the first impeller 1A and the second impeller 1B are respectively fixed to the connecting shaft 270 by fasteners (e.g., nuts) 273 fastened to the connecting shaft 270. A sleeve 280 is disposed between the first impeller 1A and the second impeller 1B, and a rotating side bearing body 272 (described later) is disposed between the fastener 273 and the second impeller 1B.

[0229] Therefore, by tightening the fastener 273, the sleeve 280 is pressed onto the first impeller 1A, and the rotating side bearing body 272 is pressed onto the second impeller 1B. As a result, the first impeller 1A is sandwiched between the front end 270a of the connecting shaft 270 and the sleeve 280, and the second impeller 1B is sandwiched between the sleeve 280 and the rotating side bearing body 272. Thus, the first impeller 1A and the second impeller 1B are securely fixed to the connecting shaft 270.

[0230] In this embodiment, the front end portion 270a of the connecting shaft 270 is disposed on the suction side, and the fastener 273 is disposed on the discharge side. In another embodiment, the front end portion 270a of the connecting shaft 270 may also have a hexagonal head or a hexagonal hole. With this structure, the operator can securely lock the fastener 273 onto the connecting shaft 270 while the front end portion 270a is fixed.

[0231] Figure 46 shows another embodiment of the connection structure between the first impeller and the second impeller and the connecting shaft. As shown in Figure 46, the motor pump MP includes collets 285 and 286, which respectively secure the first impeller 1A and the second impeller 1B to the connecting shaft 270. Since collets 285 and 286 have the same structure, the structure of collet 285 will be described below.

[0232] The collet 285 is a tapered cylindrical member with a notch extending in the direction of the centerline CL (not shown). By inserting the collet 285 into the first impeller 1A from its back side, the collet 285 is embedded in the first impeller 1A, and the first impeller 1A is secured to the connecting shaft 270. Similarly, by inserting the collet 286 into the second impeller 1B, the collet 286 is embedded in the second impeller 1B, and the second impeller 1B is secured to the connecting shaft 270. With this structure, the first impeller 1A and the second impeller 1B are more firmly secured to the connecting shaft 270.

[0233] When the first impeller 1A is fastened to the connecting shaft 270, a gap is formed between the front end portion of the collet 285 and the front end portion 270a of the connecting shaft 270. When the second impeller 1B is fastened to the connecting shaft 270, a gap is formed between the front end portion of the collet 286 and the sleeve 280.

[0234] Returning to Figures 43 and 44, the motor pump MP includes a second bearing (sliding bearing) 277, which is disposed at the rear section of the second impeller 1B and rotatably supports the connecting shaft 270. The second bearing 277 includes a rotating side bearing body 272 disposed on the side of the connecting shaft 270 and a fixed side bearing body 271 disposed on the side of the discharge housing 22.

[0235] The rotating-side bearing housing 272 is mounted on the rotating-side cylindrical body of the connecting shaft 270, and the fixed-side bearing housing 271 is mounted on the discharge housing 22, surrounding the rotating-side cylindrical body that is the rotating-side cylindrical body. The partition 245 of the discharge housing 22 has a bearing support portion 246 that supports the fixed-side bearing housing 271. The fixed-side bearing housing 271 is fixed to the bearing support portion 246. A slight gap is formed between the fixed-side bearing housing 271 and the rotating-side bearing housing 272.

[0236] Examples of materials for the second bearing 277 include ceramic or resin. If the connecting shaft 270 rotates with the rotation of the first impeller 1A, liquid enters between the fixed-side bearing body 271 and the rotating-side bearing body 272, and the fixed-side bearing body 271 supports the rotating-side bearing body 272 by the dynamic pressure of the liquid.

[0237] By configuring the second bearing 277, the connecting shaft 270 is supported not only by the first bearing 5 fixed to the first impeller 1A, but also by the second bearing 277. The connecting shaft 270, which connects to multiple impellers 1, has an increased length along its centerline CL. The motor pump MP, equipped with the first bearing 5 and the second bearing 277, suppresses shaft vibration of the connecting shaft 270 caused by its increased length, resulting in stable operation.

[0238] The assembly procedure for the motor pump MP is described below. First, fasten the first impeller 1A to the connecting shaft 270 (Step 1). Next, insert the intermediate housing 275 (refer to Figures 43 and 44) ​​into the connecting shaft 270 (Step 2), and insert the sleeve 280 into the connecting shaft 270 (Step 3). Then, insert the second impeller 1B into the connecting shaft 270, and fasten the second impeller 1B and the connecting shaft 270 (Step 4). Next, insert the rotating side bearing body 272 into the connecting shaft 270 (Step 5), and fasten the discharge housing 22 to the stator housing 20 (Step 6). Finally, fasten the fastener 273 to the connecting shaft 270 (Step 7).

[0239] In one implementation, the operator can perform step 5, then step 7, and then step 6. However, as the number of impellers 1 fixed to the connecting shaft 270 increases, the connecting shaft 270 tilts, resulting in concerns that the position of the connecting shaft 270 may deviate from the centerline CL.

[0240] Therefore, the operator preferably installs the discharge housing 22, confirming the positional relationship between the rotating side bearing 272 and the fixed side bearing 271, and fastening the fastener 273 to the connecting shaft 270. According to this embodiment, the motor pump MP is a linear motor pump with the suction port 21a and the discharge port 22a arranged side by side in a straight line. Therefore, the connecting shaft 270 can be supported by the second bearing 277, and the fastener 273 can be fastened to the connecting shaft 270.

[0241] Figure 47 shows another embodiment of the fastener. As shown in Figure 47, the fastener 290 has a diameter smaller than that of the rotating side bearing body 272. In one embodiment, the fastener 290 may also have the same diameter as the rotating side bearing body 272. A spacer 291 is disposed between the fastener 290 and the connecting shaft 270. By inserting the fastener 290 into the screw hole 270b formed at the end of the connecting shaft 270, the spacer 291 presses the rotating side bearing body 272 onto the second impeller 1B. According to this embodiment, even if the fixed side bearing body 271 is inserted, contact between the fastener 290 and the fixed side bearing body 271 can be reliably prevented.

[0242] In this embodiment, by inserting the collets 285 and 286 into the first impeller 1A and the second impeller 1B respectively, the first impeller 1A and the second impeller 1B are sufficiently secured to the connecting shaft 270. Therefore, the fastener 290 only needs to have a fastening force that restricts the rotational bearing body 272 from moving in the direction of the centerline CL.

[0243] Figure 48 shows another embodiment of the second bearing. As shown in Figure 48, the rotating side bearing body 272 can also be integrally formed with the connecting shaft 270. In this case, the connecting shaft 270 is made of the same bearing material (e.g., ceramic or steel) as the rotating side bearing body 272. In the embodiment shown in Figure 48, a fixed side bearing body 271 is arranged around the connecting shaft 270, which is integrally formed with the rotating side bearing body 272.

[0244] Figure 49 shows another embodiment of the second bearing. In the embodiment shown in Figure 49, the fixed-side bearing body 271 and the bearing support portion 246 of the ejection housing 22 are integrally formed. In this embodiment, the bearing support portion 246 is made of the same bearing material (e.g., ceramic, steel, or resin) as the fixed-side bearing body 271.

[0245] Thus, the motor pump MP may also have a first impeller 1A with the same structure as the impeller 1 shown in the embodiments of Figures 35 to 39, or it may have a first impeller 1A with the same structure as the impeller 1 shown in the embodiments of Figures 40 to 42. In one embodiment, the motor pump MP may also have a first impeller 1A with the same structure as the impeller 1 shown in the embodiments of Figures 1 to 34. In other words, the embodiments shown in Figures 1 to 49 can be combined as long as it is feasible.

[0246] Figure 50 shows the side plate provided in the motor pump of the above embodiment. As shown in Figure 50, the motor pump MP may also have a side plate 300 that restricts the liquid (processing liquid) pressurized by the impeller 1 from flowing out of the discharge housing 22. In the embodiment shown in Figure 50, the side plate 300 has a disc shape and is fixed to the return blade 30.

[0247] The side plate 300 is disposed between the main plate 10 and the return blade 30 of the impeller 1. A portion of the liquid pressurized by the impeller 1 passes through the return blade 30, through the gap between the side plate 300 and the discharge housing 22, and is discharged from the discharge port 22a. The remaining portion of the liquid pressurized by the impeller 1 flows into the gap between the side plate 300 and the main plate 10 of the impeller 1.

[0248] If impeller 1 rotates, the force (i.e., fluid force) that pushes the liquid towards the discharge housing 22 is applied to impeller 1. The liquid flow into the gap between side plate 300 and main plate 10 is restricted by side plate 300, so the pressurized liquid is retained in the gap between side plate 300 and main plate 10. The liquid retained in the gap between side plate 300 and main plate 10 is subjected to the fluid force acting on impeller 1, thus restricting the movement of impeller 1 towards the discharge housing 22.

[0249] If the motor pump MP operates at a constant speed, the thrust from the discharge housing 22 side to the suction housing 21 side acts on the impeller 1. Therefore, even if fluid force acts on the impeller 1, the impeller 1 can be stably held by the bearing 5. The embodiment shown in FIG50 illustrates an embodiment in which the side plate 300 is applied to the motor pump MP of the embodiment shown in FIG1, but the side plate 300 can also be applied to the motor pump MP of the embodiments shown in FIG2 to FIG49.

[0250] Figure 51 shows another embodiment of the side panel. As shown in Figure 51, the side panel 300 may also have an opening 300a formed in its center. As described above, liquid flowing into the gap between the side panel 300 and the main board 10 may sometimes remain in the gap between the side panel 300 and the main board 10.

[0251] In this situation, there is a concern that the liquid retained due to the rotation of impeller 1 may swirl and generate heat. By forming an opening 300a on the side plate 300, a circulating flow of liquid can be formed between the gap between the side plate 300 and the discharge housing 22 and the gap between the side plate 300 and the impeller 1. Therefore, the liquid present between the side plate 300 and the impeller 1 flows into the discharge housing 22 side, preventing the liquid from generating heat and keeping the liquid temperature constant. Furthermore, the opening 300a can also discharge the air contained in the retained liquid to the discharge housing 22 side.

[0252] In the embodiment shown in Figure 51, the opening 300a of the side plate 300 is a single opening formed on the centerline CL, and the number of openings 300a is not limited to this embodiment. The side plate 300 may also have multiple openings 300a as long as it can restrict the movement of the impeller 1 toward the discharge housing 22.

[0253] Furthermore, the opening 300a does not necessarily need to be formed on the centerline CL, as long as it can form a circulating flow of liquid. For example, the side plate 300 may also have at least one opening 300a arranged in concentric circles with the centerline CL as the center.

[0254] The shape of the opening 300a is not particularly limited; it can be circular or polygonal (e.g., triangular or quadrilateral). The size (i.e., area) of the opening 300a is also not particularly limited, as long as it can restrict the movement of the side plate 300 toward the ejection housing 22.

[0255] Figure 52 shows another embodiment of the motor pump. In the embodiment shown in Figure 52, the motor pump MP has a discharge housing 22 with a discharge port 322 extending in a vertical direction perpendicular to the centerline CL of the motor pump MP. The discharge port 322 has an upwardly opening discharge outlet 322a, and the suction inlet 21a and the discharge outlet 322a are orthogonal to each other.

[0256] In the embodiment shown in Figure 52, the motor pump MP is a so-called end-top type motor pump with an orthogonal suction inlet 21a and discharge outlet 322a. This type of motor pump MP has a compact structure. For example, depending on the installation environment of the motor pump MP, it is sometimes impossible to install a motor pump MP with a structure in which the suction inlet 21a and discharge outlet 22a are arranged side-by-side in a straight line. In such cases, an end-top type motor pump MP can also be installed. Thus, in this embodiment, the motor pump MP can be installed according to all installation environments.

[0257] As shown in Figure 52, the motor pump MP may also include a side plate 300 that restricts the flow of liquid (processing fluid) pressurized by the impeller 1 to the discharge port 322. Thus, the side plate 300 can also be applied to an upper edge type motor pump MP. In addition, in the embodiment shown in Figure 52, the side plate 300 may also have an opening 300a (see Figure 51).

[0258] The purpose of describing the above embodiments is to enable those skilled in the art to implement the present invention. It is natural that those skilled in the art can perform various modifications of the above embodiments, and the technical concept of the present invention can also be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is interpreted within the maximum scope of the technical concept defined in the claims. [Industry availability]

[0259] This invention can be used in motor pumps.

[0260] 1,1A,1B,1C: Impeller 2: Rotor 2a: Iron Heart 2b: Magnet 3: Stator 3a: Stator core 3b: Coil 5: Bearings 6: Rotating side bearing body 6a: Cylindrical section 6b: Shaft disk section 7: Fixed side bearing body 7a: Cylindrical section 7b: Shaft disk section 10: Motherboard 10a: Through hole 11: Side panel 11a: Outer edge 12: Wing 15: Inhalation section 16: Ontology part 17: Protrusion 17a: outer peripheral surface 17b: Inner circumferential surface 20: Stator housing 20a: Inner circumferential surface 21: Suction housing 21a: Inlet 22: Spitting out the shell 22a: Exhale 25: Through bolt 25a: Head 30: Return to blade 31: Sealing components 31A: Sealing component 31B: Sealing component 32, 33: Sealing components 40, 41, 42: Ditch 42a: Both ends 45: Load Reduction Structure 46: Back blades 47: Gap 50, 51: Inclined surfaces 53, 54: Inclined surfaces 60: Converter 61: Intermediate shell 65:Piping 70,70A,70B:convex part 71: Front end 75: Balance Adjustment Fixture (Central Support Adjustment Fixture) 76: Shaft 77: Fixed body 80: Center Cap 85: Balance Adjustment Fixture (Edge Support Adjustment Fixture) 86: Support 87: Shaft 90: Weight insertion hole 91: Weights 100: Control device 100a: Signal Receiving Unit 100b: Storage Department 100c: Control Unit 101: Current Sensor 102: Terminal block 105: Power Line 106: Signal Line 107: Protective Case 108: Copper Rod 110: Protective layer (cover) 117: Protrusion 118: Installation Department 120: Sealing component 121: Sealing component 125: Intermediate shell 126: Connecting axis 127A: Sealing components 127B: Sealing components 128: Extrusion side bearing 129:Flow path 130: Rotary stop 140: Connecting pipe 140a: Through hole 141: Suction housing 141a: Inlet 141b: Insertion hole 142: Spitting out the shell 142a: Exit 142b: Bolt receiving part 150: Fasteners 160: Motherboard 200: Rotor holder 201: Accommodation Department 201a: Outer surface 201b: Inner surface 201c: Corner 202: Cover plate 203: Spacer 205: Sealing components 220: Insulating materials 221: Motor frame 229: Sealing trench 230: Inner surface 231: Outer annular portion 232: Inner annular portion 233: Back side 235: Protrusion 240: partition 241: Sealing component 242: Through the hole 245: Partition 246: Bearing support section 251: Reception Department 252: Ring-shaped retainer 253: Ring Section 253a: Embedded Hole 253b: Bending section 254: Bending section 254a: Embedded Hole 254b: Bending section 255: Ontology Department 256: Bending section 257: Smooth corner surface 260: Spacer 270: Connecting axis 270a: Front end 270b: Screw hole 271: Fixed side bearing body 272: Rotating side bearing body 273: Fasteners 275: Intermediate shell 276: Liner ring 277: Second bearing 280: Sleeve 281: Hub 282: Hub 285, 286: Collets 290: Fasteners 291: Spacer 300: Side panel 300a: Opening 322: Outbound Port 322a: Exit CL: Centerline MP: Motor pump Nt: Nut PU: Pump Unit Ra: Inhalation side region Rb: Ejection side region Rc: Middle area RS: Rotary Axis S101~S104: Steps

Claims

1. A motor pump comprising: a rotor; a stator disposed radially outside the rotor; a rotor holder for holding the rotor; and an impeller, which is a press-formed article, the rotor holder being fixed to the impeller, the rotor holder comprising: an annular receiving portion formed by press forming for receiving the rotor; and an annular cover plate for closing the receiving portion.

2. The motor pump of claim 1, wherein the rotor holder has a sealing member disposed between the aforementioned receiving portion and the aforementioned cover plate.

3. The motor pump of claim 1 or 2, wherein the aforementioned rotor holder has a filler filled in the aforementioned receiving portion.

4. The motor pump of claim 1 or 2, wherein the rotor holder has a spacer disposed between the aforementioned receiving portion and the aforementioned rotor.

5. As in request item 1 or 2, the motor pump, wherein, The aforementioned receiving portion includes: an outer annular portion; and an inner annular portion disposed inside the radial direction of the aforementioned outer annular portion; the aforementioned inner annular portion has a plurality of protrusions, which form contact portions that contact the aforementioned rotor.

6. The motor pump of claim 5, wherein the inner surface of the rotor that contacts the aforementioned inner annular portion has a polygonal shape.

7. The motor pump of claim 1 or 2, wherein the motor pump has a bearing supporting the impeller and disposed outside the flow path of the impeller; the bearing has: a rotating side bearing body mounted on the rotor holder; and a fixed side bearing body disposed on the suction side of the rotating side bearing body.

8. The motor pump of claim 1 or 2, wherein the motor pump has a stator housing that houses the stator and is integrally formed with the stator by resin molding.

9. The motor pump of claim 8, wherein the motor pump has a motor frame that covers the outer peripheral surface of the stator housing and contacts the stator.

10. The motor pump of claim 7, wherein the aforementioned rotor and the aforementioned bearing are disposed in the suction side region of the aforementioned impeller.

11. A motor pump comprising: a rotor; a stator disposed radially outside the rotor; a rotor holder for holding the rotor; and an impeller, which is a resin molded article integrally formed with the rotor holder, the rotor holder comprising: an annular receiving portion formed by the resin mold for receiving the rotor; and an annular holder for closing the receiving portion, the annular holder extending along the inner circumferential surface of the rotor to transmit power applied to the rotor to the impeller.

12. The motor pump of claim 11, wherein the aforementioned annular retainer has a rotation stop structure that forms a connection portion connected to the aforementioned receiving portion.

13. The motor pump of claim 12, wherein the aforementioned rotation stop structure is an embedded hole in which a portion of the aforementioned receiving portion is embedded.

14. The motor pump as requested in item 12 or 13, wherein the aforementioned rotation stop structure is a bent portion in the shape of a U.

15. The motor pump of any one of claims 11 to 13, wherein the rotor holder has a spacer disposed between the annular holder and the rotor.

16. The motor pump of any one of claims 11 to 13, wherein the aforementioned annular retainer has a plurality of protrusions that form contact portions that contact the aforementioned rotor.

17. A motor pump as claimed in any of claims 11 to 13, wherein the inner surface of the rotor that contacts the aforementioned annular retainer has a polygonal shape.

18. A motor pump according to any one of claims 11 to 13, wherein the motor pump has a bearing supporting the impeller and disposed outside the flow path of the impeller; the bearing has: a rotating side bearing body mounted on the rotor holder; and a fixed side bearing body disposed on the suction side of the rotating side bearing body.

19. The motor pump of any one of claims 11 to 13, wherein the motor pump has a stator housing that houses the stator and is integrally formed with the stator by resin molding.

20. The motor pump of claim 19, wherein the motor pump has a motor frame that covers the outer peripheral surface of the stator housing and contacts the stator.

21. The motor pump of claim 18, wherein the aforementioned rotor and the aforementioned bearing are disposed in the suction side region of the aforementioned impeller.

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