JP2021173255A - Pump device and water supply device - Google Patents

Abstract

To provide a small-sized pump device with a high lift while improving suction performance.SOLUTION: A pump device 100 comprises a plurality of pump units 1A, 1B, 1C connected continuously in series. Each pump unit 1 comprises: an impeller 14 in which the magnet 5 is embedded; a motor stator 6 arranged at a position facing the magnet 5; a pump casing 2 that houses the impeller 14; and a motor casing 3 that houses the motor stator 6. The first stage pump unit 1A located at the earliest stage among the plurality of pump units 1A, 1B, 1C has suction performance that allows handling liquid to be transferred at a desired flow rate to the second stage pump unit 2B following the first stage pump unit 1A.SELECTED DRAWING: Figure 2

Description

The present invention relates to a pump device, and more particularly to a pump device equipped with a motor pump. Furthermore, the present invention relates to a water supply device equipped with such a pump device.

The pump device is a device used to transfer the handling liquid from a transfer source such as a suction tank to a transfer destination such as a discharge tank, and has a pump for applying the required pressure to the handling liquid. .. In addition, the pump device may be arranged in a circulation line for circulating the handling liquid. In this case, the pump of the pump device raises the pressure of the handling liquid so that the handling liquid flows appropriately through the circulation line.

Depending on the installation location of the pump device and / or the type of liquid to be handled, leakage of the liquid to be handled from the pump device may be disliked by the user. For example, when the leakage of the handling liquid causes the gas detector installed in the factory to erroneously detect, it is necessary to avoid the leakage of the handling liquid as much as possible. Further, even when the handling liquid is an expensive liquid, it is desired to prevent leakage of the handling liquid so that the running cost does not increase.

In order to prevent leakage of the handling liquid from the pump device, a canned motor pump (hereinafter, simply referred to as "motor pump") may be used as the pump of the pump device. Patent Document 1 discloses a motor pump in which an impeller in which a permanent magnet is embedded is rotated by a magnetic field generated by a motor stator. Such a motor pump can be relatively small in size while preventing leakage of the handling liquid.

Japanese Patent No. 2544825 U.S. Pat. No. 9,879,680

However, since the impeller of the motor pump is operated at a relatively high rotation speed, it is difficult to secure the suction performance of the pump device. That is, it is not possible to suck an appropriate amount of the handling liquid into the pump device while adjusting the pressure of the handling liquid discharged from the pump device to the user's request.

Patent Document 2 discloses a pump device in which a plurality of impellers are connected in series with a common rotating shaft. With such a configuration, there is a possibility that the suction performance of the pump device can be improved to some extent.

However, since all of the plurality of impellers are rotated at the same rotation speed, there is a limit to improving the suction performance of the pump device while matching the pressure of the handling liquid discharged from the pump device to the user's request. be.

Therefore, an object of the present invention is to provide a small pump device with a high lift while improving the suction performance. Furthermore, an object of the present invention is to provide a water supply device equipped with such a pump device.

In one aspect, it is a pump device that transfers a handling liquid, and includes a plurality of pump units that are continuously connected in series, and each pump unit has an impeller in which a magnet is embedded and a position facing the magnet. A first-stage pump located in the frontmost stage of the plurality of pump units, comprising a motor stator arranged in, a pump casing accommodating the impeller, and a motor casing accommodating the motor stator. The unit is provided with a pump device having a suction performance capable of transferring the handling liquid at a desired flow rate to a second stage pump unit following the first stage pump unit.

In one aspect, the impeller of at least one of the plurality of pump units is operated at a rotation speed different from the rotation speed of the impellers of the other pump units.
In one aspect, the impeller of the first stage pump unit is operated at a rotation speed lower than the rotation speed of the impeller of a pump unit other than the first stage pump unit.
In one aspect, the suction diameter of the impeller of the first stage pump unit is larger than the suction diameter of the impeller of the pump unit other than the first stage pump unit.
In one aspect, the outlet width of the impeller of the first stage pump unit is larger than the outlet width of the impeller of a pump unit other than the first stage pump unit.
In one aspect, the impellers of the plurality of pump units have the same shape.

In one aspect, the motor casing has a motor chamber in which the motor stator is housed and at least one motor chamber inlet hole for allowing the handling liquid to flow into the motor chamber.
In one aspect, the motor casing has at least one motor chamber outlet hole for discharging the handling liquid in the motor chamber by the handling liquid flowing into the motor chamber through the motor chamber inlet hole. There is.
In one aspect, the first-stage pump unit further includes a suction casing having a suction port, and the suction casing is a guide member that guides the handling liquid that has passed through the suction port so as to pass through the motor chamber inlet hole. Is placed.

In one aspect, each pump unit of the plurality of pump units has an inverter device for operating the impeller at a variable speed.
In one aspect, each pump unit further comprises an inverter casing having an inverter chamber in which the inverter device is housed, the inverter casing having at least one inverter chamber inlet hole for allowing the handling liquid to flow into the inverter chamber. have.
In one aspect, the inverter casing is connected to the motor casing, and the inverter casing has at least one communication hole for allowing the handling liquid in the inverter chamber to flow into the motor casing.
In one aspect, each pump unit of the plurality of pump units further includes an inverter device for operating the impeller at a variable speed, and an inverter casing having an inverter chamber in which the inverter device is housed. It is connected to the motor casing, and the inverter casing is made to flow into the inverter chamber through at least one communication hole for flowing the handling liquid in the motor chamber into the inverter chamber and the communication hole. It has at least one inverter chamber outlet hole for discharging the handling liquid in the inverter chamber depending on the handling liquid.
In one aspect, the handling liquid has an insulating property.

In one aspect, a control unit that controls the operation of the plurality of pump units is further provided, and the control unit first starts the first stage pump unit when a predetermined start condition is satisfied, and when a predetermined stop condition is satisfied, the control unit is described. Automatic operation control is performed to stop the first stage pump unit at the end.
In one aspect, a pressure sensor for measuring the discharge pressures of the plurality of pump units is further provided, and the control unit determines that the start condition is satisfied when the discharge pressure drops to a predetermined starting pressure. ..
In one aspect, a flow rate detector for detecting a small amount of water in which the flow rate of the handling liquid discharged from the plurality of pump units is equal to or less than a predetermined small amount of water is further provided, and the control unit is provided with a flow rate detector for which the flow rate detector has a small amount of water. When the state is detected, it is determined that the stop condition is satisfied.

In one aspect, the control unit starts a second pump unit different from the first stage pump unit when the next pump unit start condition is satisfied during the operation of the first stage pump unit.
In one aspect, a pressure sensor for measuring the discharge pressure of the plurality of pump units is further provided, and the control unit receives when the discharge pressure becomes equal to or lower than a predetermined threshold value during the operation of the first stage pump unit. It is determined that the conditions for starting the next pump unit are satisfied.
In one aspect, the control unit stops the second pump unit before the first stage pump unit when the next pump unit stop condition is satisfied during the operation of the first stage pump unit and the second pump unit.
In one aspect, the control unit determines that the next pump unit stop condition is satisfied when the discharge pressure becomes equal to or higher than a predetermined threshold value during the operation of the first stage pump unit.

In one aspect, a water supply device including at least one pump device is provided, wherein the pump device is the pump device.

According to the present invention, the pump device includes a plurality of pump units that are continuously connected in series, and the rotation speed of the impeller of each pump unit can be controlled independently. Further, the first-stage pump unit has a suction performance capable of transferring the handling liquid to the second-stage pump unit at a desired flow rate. Therefore, by freely adjusting the pressure of the handling liquid having a desired flow rate in the pump unit after the first stage pump unit, it is possible to provide a small pump device with a high lift with improved suction performance.

FIG. 1 (a) is a schematic view showing an example of the arrangement of the pump device according to the embodiment, and FIG. 1 (b) is a schematic diagram showing another example of the arrangement of the pump device shown in FIG. 1 (a). It is a figure. FIG. 2 is a schematic cross-sectional view of the pump device shown in FIG. 1 (a). FIG. 3A is a schematic view showing an example of a drive circuit and a control unit connected to a plurality of pump units, and FIG. 3B is a schematic diagram of a drive circuit and a control unit connected to the plurality of pump units. FIG. 3C is a schematic diagram showing another example, and FIG. 3C is a schematic diagram showing still another example of a drive circuit and a control unit connected to a plurality of pump units. FIG. 4 is a schematic cross-sectional view showing an enlarged impeller of the first stage pump unit. FIG. 5A is a graph schematically showing an example of noise generated when a plurality of pump units each having an impeller having the same configuration are operated at the same rotation speed. b) is a graph schematically showing an example of noise generated when a plurality of pump units each having an impeller having the same configuration are operated at different rotation speeds. FIG. 6 is a schematic cross-sectional view of the pump device according to another embodiment. FIG. 7 is a schematic cross-sectional view of the pump device according to still another embodiment. FIG. 8 is a schematic view showing a plurality of opening holes formed in the bottom wall of the suction casing. FIG. 9 is a schematic cross-sectional view for explaining a modified example of the pump device shown in FIG. 7. FIG. 10 is a schematic cross-sectional view of the pump device according to still another embodiment. FIG. 11 is a schematic cross-sectional view of the flow path of the inverter casing provided with the heat radiation fins. FIG. 12 is a schematic cross-sectional view of the pump device according to still another embodiment. FIG. 13 is a schematic cross-sectional view for explaining a modified example of the pump device shown in FIG. FIG. 14 is a schematic cross-sectional view for explaining a modified example of the pump device shown in FIG. FIG. 15 is a schematic cross-sectional view for explaining another modification of the pump device shown in FIG. FIG. 16 is a schematic view showing an example of a water supply device equipped with the pump device according to the above-described embodiment. FIG. 17 is a flowchart for explaining an example of a starting operation of the pump device mounted on the water supply device shown in FIG. FIG. 18 is a flowchart for explaining an example of a stop operation of the pump device mounted on the water supply device shown in FIG. FIG. 19 is a schematic view showing another example of the water supply device equipped with the pump device according to the above-described embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding components are designated by the same reference numerals, and duplicate description will be omitted. Further, in the drawings and description below, the subscripts (A, B, C), which are uppercase alphabets, are added to the end of each code, and the components with the subscripts are attached to any pump unit of the pump device. It is a comprehensive symbol indicating whether or not it belongs. For example, the subscript "A" is attached to the component of the first stage pump unit located at the frontmost stage among the plurality of pump units, and the subscript "B" is attached to the component of the second stage pump unit following the first stage pump unit. Attached. Further, the subscripts "A, B, C" may be omitted when it is not necessary to distinguish them and when the components common to a plurality of pump units are represented.

FIG. 1 (a) is a schematic view showing an example of the arrangement of the pump device according to the embodiment, and FIG. 1 (b) is a schematic diagram showing another example of the arrangement of the pump device shown in FIG. 1 (a). It is a figure. The pump device 100 shown in FIGS. 1A and 1B has a plurality of pump units 1A, 1B, and 1C, and transfers the handling liquid stored in the suction tank 110, which is an example of the transfer source. Transfer to the destination (not shown). Although the detailed configuration of the pump device 100 will be described later, these pump units 1A, 1B, and 1C are continuously arranged in series.

In the pump device 100 shown in FIG. 1 (a), the plurality of pump units 1A, 1B, 1C are arranged in the vertical direction, and in the pump device 100 shown in FIG. 1 (b), the plurality of pump units 1A, 1B, 1B, 1Cs are arranged horizontally. In the embodiment shown in FIGS. 1 (a) and 1 (b), the pump device 100 sucks in the handling liquid having a liquid level located below the pump device 100 (pump units 1A, 1B, 1C). The pump units 1A, 1B, and 1C increase the pressure of the handling liquid to transfer the handling liquid to the transfer destination.

The position of the pump device 100 with respect to the liquid level of the liquid to be handled in the suction tank 110 is arbitrary, and is not limited to the examples shown in FIGS. 1 (a) and 1 (b). For example, the pump device 100 may be located below the liquid level of the liquid to be handled in the suction tank 110. Further, the plurality of pump units 1 of the pump device 100 may be arranged obliquely with respect to the horizontal direction or the vertical direction. Further, the number of pump units 1 included in the pump device 100 is also arbitrary. For example, the pump device 100 may have two or less pump units 1 or may have four or more pump units 1.

FIG. 2 is a schematic cross-sectional view of the pump device 100 shown in FIG. 1 (a). The pump device 100 has a plurality of (three in FIG. 2) pump units 1A, 1B, and 1C connected in series. These pump units 1A, 1B, and 1C are motor pumps (canned motor pumps) capable of preventing leakage of the handling liquid. Hereinafter, the configuration of the first stage pump unit 1A located at the earliest stage among the plurality of pump units 1A, 1B, 1C will be described, but the pump units 1A, 1B, 1C have the same configuration unless otherwise specified. However, the duplicate description will be omitted.

The first-stage pump unit 1A includes an impeller 14A in which an annular permanent magnet 5A is embedded, a motor stator 6A that generates a magnetic force acting on the permanent magnet 5A, a pump casing 2A that houses the impeller 14A, and a motor stator. It includes a motor casing 3A having a motor chamber 33A accommodating 6A, and a bearing 10A supporting the radial load and the thrust load of the impeller 14A.

An O-ring 9A as a sealing member is provided between the pump casing 2A and the motor casing 3A. The impeller 14A and the motor casing 3A face each other through a minute gap, and the impeller 14A rotates when the rotating magnetic field generated by the motor stator 6A acts on the permanent magnet 5A. The size of the gap between the impeller 14A and the motor casing 3A is arbitrary as long as the impeller 14A can be rotated by the rotating magnetic field generated by the motor stator 6A. However, the size of this gap is preferably as small as possible so that the impeller 14A and the motor casing 3A do not come into contact with each other.

The motor stator 6A and the bearing 10A are arranged on the suction side of the impeller 14A, and the impeller 14A is rotatably supported by a single bearing 10A. In the present embodiment, the bearing 10A is a slide bearing (dynamic pressure bearing) that utilizes the dynamic pressure of the handling liquid. In one embodiment, the bearing 10A may be a plain bearing that does not utilize the dynamic pressure of the handling liquid.

The bearing 10A shown in FIG. 2 is composed of a combination of a rotating side bearing element 11A and a fixed side bearing element 12A that are loosely engaged with each other. The rotary side bearing element 11A is fixed to the impeller 14A and is arranged so as to surround the liquid inlet of the impeller 14A. The fixed side bearing element 12A is fixed to the motor casing 3A and is arranged on the suction side of the rotating side bearing element 11A. The fixed side bearing element 12A has a radial surface 12Aa that supports the radial load of the impeller 14A and a thrust surface 12Ab that supports the thrust load of the impeller 1. The radial surface 12Aa is parallel to the axis of the impeller 14A, and the thrust surface 12Ab is perpendicular to the axis of the impeller 14A.

The rotating side bearing element 11A has a ring shape, the inner peripheral surface of the rotating side bearing element 11A faces the radial surface 12Aa of the fixed side bearing element 12A, and the side surface of the rotating side bearing element 11A faces the fixed side bearing element 12A. Facing the thrust surface 12Ab of. A minute gap is formed between the inner peripheral surface of the rotating side bearing element 11A and the radial surface 12Aa, and between the side surface of the rotating side bearing element 11A and the thrust surface 12Ab. Further, a spiral groove (not shown) for generating dynamic pressure is formed on the inner peripheral surface and the side surface of the rotating side bearing element 11A.

A part of the handling liquid discharged from the impeller 14A is guided to the bearing 10A through a minute gap between the impeller 14A and the motor casing 3A. When the rotating side bearing element 11A rotates together with the impeller 14A, a dynamic pressure of the handling liquid is generated between the rotating side bearing element 11A and the fixed side bearing element 12A, whereby the impeller 14A is non-contactly supported by the bearing 10A. Will be done. Since the fixed side bearing element 12A supports the rotating side bearing element 11A by the orthogonal radial surface 12Aa and the thrust surface 12Ab, the tilt of the impeller 14A is regulated by the bearing 10A. The bearing 10A (that is, the rotating side bearing element 11A and the fixed side bearing element 12A) is formed of, for example, a material having excellent wear resistance such as ceramic or carbon.

An annular magnet yoke (magnetic material) 19A is embedded in the impeller 14A adjacent to the annular permanent magnet 5A. The permanent magnet 5A is arranged on the suction side of the magnet yoke 19A. The permanent magnet 5A and the motor stator 6A are arranged so as to face each other, and the motor stator 6A is arranged on the suction side of the impeller 14A.

In the impeller 14A shown in FIG. 2, one permanent magnet 5A having a ring shape is embedded, but this embodiment is not limited to this example. For example, a plurality of permanent magnets 5A may be embedded in the impeller 14A. In this case, a plurality of permanent magnets 5A embedded in the impeller 14A are arranged in an annular shape, and each permanent magnet 5A has, for example, a fan shape.

The impeller 14A is made of a non-magnetic material. Further, the impeller 14A is preferably made of a material that is slippery and less likely to wear. Examples of such materials include resins such as Teflon®, PPS (polyphenylene sulfide), and PEEK (polyetheretherketone), and ceramics.

The pump casing 2A may be formed of a magnetic material (for example, metal) or a non-magnetic material. When the pump casing 2A is made of a non-magnetic material, the pump casing 2A can be made of the same material as the impeller 14A.

In this embodiment, the motor casing 3A has a ring-shaped motor chamber 33A. The motor stator 6A is housed in the motor chamber 33A. The motor stator 6A has a stator core 23A having a plurality of teeth and a stator coil 24A wound around each of these teeth. The teeth and the stator coil 24A are arranged in an annular shape, and the impeller 14A and the motor stator 6A are arranged concentrically with the bearing 10A.

The motor casing 3A may be formed from a metal material. However, from the viewpoint of ensuring the electrical insulation of the motor stator 6A and preventing the generation of eddy currents, the motor casing 3A is preferably formed of a non-metallic material. Examples of the non-metallic material forming the motor casing 3A include resins such as PPS (polyphenylene sulfide), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), and PEEK (polyetheretherketone). .. The motor casing 3A may be formed of the same resin material as the impeller 14A. The resin motor casing 3A has an advantage that even if the stator coil 24A comes into contact with the motor casing 3A, the electrical insulation of the stator coil 24A is maintained and there is no risk of ground fault.

Three lead wires 17A are connected to the stator coil 24A. As will be described later, the end of the lead wire 17A is connected to a drive circuit, and this drive circuit is connected to a control unit that controls the operation of the drive circuit and a power supply. A rotating magnetic field is generated in the motor stator 6A by the current supplied from the drive circuit to the stator coil 24A via the lead wire 17A. The rotating magnetic field acts on the permanent magnet 5A embedded in the impeller 14A, which causes the impeller 14A to rotate.

Unlike the other pump units 1B and 1C, the first-stage pump unit 1A located at the foremost stage among the plurality of pump units 1A, 1B and 1C has a suction casing 4 having a suction port 4a. The motor casing 3A is sandwiched between the suction casing 4 and the pump casing 2A. More specifically, the suction casing 4 is connected to the liquid inlet side of the motor casing 3A, and the pump casing 2A is connected to the liquid outlet side of the motor casing 3A. The suction casing 4 has a suction port 4a that opens upward and a casing main body 4b that is connected to the suction port 4a, and the suction port 4a is connected to an inlet line for a handling liquid (not shown). The inlet line is a line extending from a transfer source such as a suction tank to the pump device 100. In the present embodiment, the suction port 4a is arranged in the center of the suction casing 4. Specifically, the center of the suction port 4a is on the central axis of the casing main body 4b of the suction casing 4. The suction casing 4 may be formed of the same material as the impeller 14A. Further, the suction port 4a may be formed integrally with the casing main body 4b.

When the impeller 14A rotates, the handling liquid is introduced into the liquid inlet of the impeller 14A from the suction port 4a of the suction casing 4. The handling liquid is boosted by the rotation of the impeller 14A and transferred to the second stage pump unit 1B following the first stage pump unit 1A. While the impeller 14A is rotating, the back surface of the impeller 14A is pressed toward the suction side (that is, toward the suction port 4a) by the boosted handling liquid. Since the bearing 10A is arranged on the suction side of the impeller 14A, the thrust load of the impeller 14A is supported from the suction side. According to the configuration according to the present embodiment, since the radial load and the thrust load of the impeller 14A can be supported by one bearing 10A in a non-contact manner, a compact pump unit that does not generate particles can be realized. Can be done.

Since the other pump units 1B and 1C have the same configuration, each pump unit 1A, 1B and 1C can be compactly configured. Therefore, by continuously connecting these pump units 1A, 1B, and 1C in series, it is possible to achieve miniaturization of the pump device 100.

A discharge port 16 is formed in the pump casing 2C of the third-stage pump unit 1C arranged at the rearmost stage of the plurality of pump units 1A, 1B, and 1C. The discharge port 16 is connected to an outlet line for a handling liquid (not shown). The outlet line is, for example, a line extending from the pump device 100 to a transfer destination such as a discharge tank. In the present embodiment, the discharge port 16 is arranged at the center of the pump casing 2C of the third stage pump unit 1C. Specifically, the center of the discharge port 16 is on the central axis of the pump casing 2C of the third stage pump unit 1C.

The suction casing 4, the motor casing 3A and the pump casing 2A of the first stage pump unit 1A, the motor casing 3B and the pump casing 2B of the second stage pump unit 1B, and the motor casing 3C and the pump casing 2C of the third stage pump unit 1C are They are arranged in this order, and in this state, they are integrally connected by a plurality of connecting bolts (not shown).

In the present embodiment, the first-stage pump unit 1A has a suction performance capable of transferring the handling liquid to the second-stage pump unit 1B following the first-stage pump unit 1A at a desired flow rate. For example, the first-stage pump unit 1A has a lift H (see FIGS. 1A and 1B) capable of transferring the handling liquid stored in the suction tank 110 to the second-stage pump unit 1B at a desired flow rate. ..

The handling liquid sucked into the first stage pump unit 1A is transferred to the second stage pump unit 1B and boosted by the second stage pump unit 1B. The handling liquid boosted by the second-stage pump unit 1B is transferred to the third-stage pump unit 1C, and is further boosted by the third-stage pump unit 1C. After that, the handling liquid is discharged from the discharge port 16 formed in the pump casing 2C of the third stage pump unit 1C to the outlet line (not shown).

FIG. 3A is a schematic view showing an example of a drive circuit and a control unit connected to a plurality of pump units 1A, 1B, 1C, and FIG. 3B is a schematic diagram showing a plurality of pump units 1A, 1B, 1C. 3 (c) is a schematic view showing another example of the drive circuit and the control unit connected to the pump unit 1A, 1B, 1C, and still another example of the drive circuit and the control unit connected to the plurality of pump units 1A, 1B, 1C. It is a schematic diagram which shows.

As described above, three lead wires 17A are connected to the stator coil 24A of the first stage pump unit 1A, and the end of the lead wires 17A is connected to the drive circuit 7A. Similarly, the ends of the three lead wires 17B connected to the stator coil 24B of the second stage pump unit 1B are connected to the drive circuit 7B and connected to the stator coil 24C of the third stage pump unit 1C. The ends of the three lead wires 17C are connected to the drive circuit 7C.

In the example shown in FIG. 3A, the drive circuit 7A is connected to the control unit 8A that controls the operation of the drive circuit 7A and the power supply 9A. Similarly, the drive circuit 7B is connected to the control unit 8B that controls the operation of the drive circuit 7B and the power supply 9B, and the drive circuit 7C has the control unit 8C and the power supply 9C that control the operation of the drive circuit 7C. Connected to. The drive circuits 7A, 7B, 7C are, for example, an inverter device, and the control units 8A, 8B, 8C use a power element (for example, a switching element such as an IGBT element) arranged in the inverter device to power the power supply 9A. , 9B, 9C control the timing of the current supplied to the stator coils 24A, 24B, 24C, respectively.

In the example shown in FIG. 3B, the drive circuits 7A, 7B, and 7C are connected to the common power supply 9. In the example shown in FIG. 3C, the operations of the drive circuits 7A, 7B, and 7C are further controlled by the common control unit 8.

In any of the examples shown in FIGS. 3A to 3C, the control unit 8A, 8B, 8C, or the control unit 8 determines the rotation speed of the impellers 14A, 14B, 14C to drive circuits 7A, 7B, 7C. Each can be adjusted arbitrarily and independently via. That is, the control units 8A, 8B, 8C, or the control unit 8 can independently control the operating speeds of the pump units 1A, 1B, and 1C via the drive circuits 7A, 7B, and 7C.

According to such a configuration, the first stage pump unit 1A of the pump device 100 transfers the handling liquid at a desired flow rate in two stages from the transfer source (for example, the suction tank 110 shown in FIGS. 1A and 1B). It can be transferred to the eye pump unit 1B. As described above, the control units 8A, 8B, 8C, or the control unit 8 can independently control the operating speeds of the pump units 1A, 1B, and 1C, so that the pump units 1B after the first stage pump unit 1A, With 1C, the pressure of the handling liquid can be freely adjusted. As a result, it is possible to provide a small pump device 100 with a high lift and improved suction performance.

As described above, the first-stage pump unit 1A has a suction performance capable of transferring the handling liquid to the second-stage pump unit 1B at a desired flow rate. In the present embodiment, the control unit 8A, 8B, 8C, or the control unit 8 operates the first stage pump unit 1A at a speed lower than the operating speed of the other pump units 1B, 1C. In general, by reducing the operating speed of the pump (that is, the rotational speed of the impeller), the suction performance of the pump can be increased as compared with the case of operating at high speed. However, the pump head is lower than when operating at high speed.

In the present embodiment, the first-stage pump unit 1A transfers the handling liquid to the second-stage pump unit 1B at a desired flow rate, and the pressure of the handling liquid is freely adjusted by the pump units 1B and 1C after the first-stage pump unit 1A. Therefore, even if the operating speed of the first stage pump unit 1A is reduced, the pump device 100 can secure a desired head. In this case, since the impellers 14A, 14B, and 14C having the same shape can be used, the manufacturing cost and the management cost of the pump device 100 can be reduced. Of course, in order to secure a desired lift, the pump units 1B and 1C other than the first stage pump unit 1A may be operated at different operating speeds.

In order to ensure the suction performance required for the first stage pump unit 1A, the configuration of the impeller 14A of the first stage pump unit 1A is different from the configuration of the impellers 14B and 14C of the pump units 1B and 1C other than the first stage pump unit 1A. You may.

FIG. 4 is an enlarged schematic cross-sectional view of the impeller 14A of the first stage pump unit 1A. In order to ensure the suction performance required for the first stage pump unit 1A, the suction diameter d1 of the impeller 14A of the first stage pump unit 1A is made larger than the suction diameter d1 of the impellers 14B and 14C of the other pump units 1B and 1C. You may. In one embodiment, the suction ports of the impellers 14B and 14C of the other pump units 1B and 1C may be different from each other. In general, the suction performance of the pump can be increased by increasing the suction diameter of the impeller of the pump. The impeller 14A having a suction diameter d1 larger than the suction diameters of the impellers 14B and 14C of the other pump units 1B and 1C may be rotated at a lower speed than the impellers 14B and 14C.

Instead of making the suction diameter d1 of the impeller 14A larger than the suction diameter of the other impellers 14B and 14C, or in addition to this, the outlet width b of the impeller 14A is changed to the outlet width of the other impellers 14B and 14C. May be larger than. In one embodiment, the outlet widths of the impellers 14B and 14C of the other pump units 1B and 1C may be different from each other. In general, the suction performance of the pump can be increased by increasing the outlet width of the impeller of the pump. The impeller 14A having a suction port diameter d1 and / or an outlet width b larger than the suction port diameter and / or the outlet width of the impellers 14B and 14C of the other pump units 1B and 1C is slower than the impellers 14B and 14C. You may rotate with.

Further, according to the pump device 100 according to the present embodiment, vibration and noise generated from the pump device 100 can be reduced. FIG. 5A is a graph schematically showing an example of noise generated when a plurality of pump units each having an impeller having the same configuration are operated at the same rotation speed. b) is a graph schematically showing an example of noise generated when a plurality of pump units each having an impeller having the same configuration are operated at different rotation speeds. In FIGS. 5 (a) and 5 (b), the vertical axis represents the sound pressure level of noise, and the horizontal axis represents the frequency of noise.

As shown in FIG. 5A, when a plurality of pump units 1A, 1B, 1C each having impellers 14A, 14B, 14C having the same configuration are operated at the same rotation speed, the pump units 1A, 1B are operated. , The noise generated in 1C may be superimposed, and a large noise may be generated from the pump device 100. The vibrations generated in each of the pump units 1A, 1B, and 1C may be increased by being superimposed (for example, resonating) in the same manner. Further, the frequency of the pulsation of the discharge pressure generated in each of the pump units 1A, 1B, and 1C may be the same, and in this case, the amplitude of the vibration generated in the pump device 100 becomes large.

In the present embodiment, the control units 8A, 8B, 8C, or the control unit 8 can independently control the operating speeds of the pump units 1A, 1B, and 1C. Therefore, the impeller 14 of at least one pump unit 1 of the plurality of pump units 1A, 1B, and 1C can be operated at a rotation speed different from the rotation speed of the impeller 14 of the other pump units 1. As a result, vibration and noise generated from the pump device 100 can be reduced. As shown in FIG. 5B, by making the operating speeds of the pump units 1A, 1B, and 1C different, the vibration and noise generated from the pump device 100 can be reduced most. Further, since it is possible to prevent all the frequencies of the discharge pressure pulsations generated in the pump units 1A, 1B, and 1C from being the same, the amplitude of the vibration generated in the pump device 100 can be reduced.

In order to prevent all the vibrations and noises generated from the pump device 100 from being superimposed, and to prevent all the frequencies of the discharge pressure pulsations generated in the pump units 1A, 1B, and 1C from being the same. In addition, the configuration of the impeller 14 of at least one of the plurality of pump units 1A, 1B, 1C may be different from the configuration of the impeller 14 of the other pump unit 1. For example, the number of blades 20A (see FIG. 4) of the impeller 14A may be different from the number of blades of the other impellers 14B and 14C. Instead of or in addition to having different numbers of blades, the diameter d2 of the impeller 14A (see FIG. 4) may be different from the diameters of the other impellers 14B, 14C. In one embodiment, the configurations (eg, number of blades and / or diameter) of the impellers 14A, 14B, 14C of the plurality of pump units 1A, 1B, 1C may be different from each other.

FIG. 6 is a schematic cross-sectional view of the pump device according to another embodiment. When the pump device 100 having a plurality of pump units 1A, 1B, 1C is operated, the motor stators 6A, 6B, 6C (particularly, the stator coils 24A, 24B, 24C) generate heat. Excessive heat generation of the motor stators 6A, 6B, 6C leads to deterioration or damage of the motor stators 6A, 6B, 6C. Therefore, the pump device 100 shown in FIG. 6 has a configuration for efficiently cooling the motor stators 6A, 6B, and 6C. Since the configurations not particularly described in this embodiment are the same as those in the above-described embodiment, the duplicated description will be omitted.

The suction casing 4 of the first-stage pump unit 1A shown in FIG. 6 is a guide member that changes the flow direction of the handling liquid sucked from the suction port 4a to guide the handling liquid to pass through the first-stage diffuser 21 (described later). Has 15. In this embodiment, the guide member 15 has a substantially disk shape.

The handling liquid sucked into the suction casing 4 from the suction port 4a by the guide member 15 flows on one surface (lower surface in FIG. 6) of the guide member 15 toward the outer side in the radial direction of the suction casing 4, and the casing main body 4b Collides with the inner surface of the side wall of the. Then, the handling liquid wraps around the other surface (upper surface in FIG. 6) of the guide member 15 and flows inward in the radial direction of the suction casing 4. That is, the guide member 15 forms a suction flow path 4c for the handling liquid that radiates outward in the radial direction of the suction casing 4 and then converges inward in the radial direction of the suction casing 4. The suction flow path 4c is formed in the casing main body 4b, extends from the suction port 4a, and is connected to the flow path 3Aa formed in the motor casing 3A.

A plurality of first-stage diffusers 21 are arranged in the suction flow path 4c. The first-stage diffuser 21 appropriately guides the handling liquid flowing through the suction flow path 4c to the flow path 3Aa formed in the motor casing 3A. The first-stage diffuser 21 is fixed to the wall surface of the suction flow path 4c. More specifically, the first-stage diffuser 21 is fixed to the inner surface of the bottom wall of the casing main body 4b of the suction casing 4 that forms the wall surface of the suction flow path 4c. In the present embodiment, the guide member 15 is supported by a plurality of first-stage diffusers 21, and in this state, the center of the guide member 15 is on the central axis (of the casing main body 4b) of the suction casing 4.

Liquid flow paths 3Aa and 10Aa are formed in the central portions of the motor casing 3A and the bearing 10A of the first stage pump unit 1A, respectively. These liquid flow paths 3Aa and 10Aa are connected in a row. The handling liquid sucked from the suction port 4a and flowing through the suction flow path 4c of the suction casing 4 flows linearly through the flow path 3Aa of the motor casing 3A and the flow path 10Aa of the bearing 10A to the liquid inlet of the impeller 14A. Be sucked in. As described above, the flow paths 4c, 3Aa, and 10Aa form one liquid flow path extending from the suction port 4a to the liquid inlet of the impeller 14A.

The pump casing 2A of the first-stage pump unit 1A has a communication flow path 26A extending from the impeller 14A to the second-stage pump unit 1B. The handling liquid discharged from the impeller 14A flows into the motor casing 3B of the second stage pump unit 1B through the communication flow path 26A. An intermediate diffuser 22A is fixed to the wall surface of the communication flow path 26A. More specifically, the intermediate diffuser 22A is fixed to the inner surface of the bottom wall of the pump casing 2A forming the wall surface of the communication flow path 26A. The handling liquid discharged from the impeller 14A is guided by the intermediate diffuser 22A to the flow path 3Ba formed in the motor casing 3B of the second stage pump unit 1B.

Similar to the first stage pump unit 1A, liquid flow paths 3Ba and 10Ba are formed in the center of the motor casing 3B and the bearing 10B of the second stage pump unit 1B, respectively, and the liquid flow paths 3Ba and 10Ba are also connected in a row. Has been done. The handling liquid that has flowed from the first-stage pump unit 1A to the second-stage pump unit 1B flows linearly through the flow path 3Ba of the motor casing 3B and the flow path 10Ba of the bearing 10B, and is sucked into the liquid inlet of the impeller 14B.

The pump casing 2B of the second-stage pump unit 1B also has a communication flow path 26B extending from the impeller 14B to the third-stage pump unit 1C. The handling liquid discharged from the impeller 14B flows into the motor casing 3C of the third stage pump unit 1C through the communication flow path 26B. An intermediate diffuser 22B is fixed to the wall surface of the communication flow path 26B. More specifically, the intermediate diffuser 22B is fixed to the inner surface of the bottom wall of the pump casing 2B forming the wall surface of the communication flow path 26B. The handling liquid discharged from the impeller 14B is guided by the intermediate diffuser 22B to the flow path 3Ca formed in the motor casing 3C of the third stage pump unit 1C.

The third-stage pump unit 1C also has the same configuration as the second-stage pump unit 1B. That is, the handling liquid that has flowed into the third stage pump unit 1C through the communication flow path 26B of the second stage pump unit 1B flows through the liquid flow paths 3Ca and 10Ca formed in the central portions of the motor casing 3C and the bearing 10C. It is sucked into the liquid inlet of the impeller 14C. The handling liquid discharged from the impeller 14C flows through the communication flow path 26C formed in the pump casing 2C of the third stage pump unit 1C and is discharged from the discharge port 16. In the illustrated example, the intermediate diffuser 22C is arranged in the communication flow path 26C, but the intermediate diffuser 22C may be omitted.

The motor stator 6A of the first-stage pump unit 1A is in contact with a surface opposite to the wall surface on which the first-stage diffuser 21 is fixed. More specifically, the motor stator 6A has an annular protrusion 25A, and the tip of the protrusion 25A contacts the outer surface of the bottom wall of the casing body 4b of the suction casing 4 to which the first stage diffuser 21 is fixed. doing. The heat generated in the motor stator 6A is transferred from the protrusion 25A to the first stage diffuser 21 via the casing main body 4b. Since the first-stage diffuser 21 is in contact with the handling liquid flowing through the suction flow path 4c, the heat transferred from the protrusion 25A of the motor stator 6A to the first-stage diffuser 21 via the casing body 4b is efficiently dissipated to the handling liquid. NS. As a result, the motor stator 6A can be efficiently cooled.

Similarly, the motor stator 6B of the second stage pump unit 1B is in contact with the surface opposite to the wall surface on which the intermediate diffuser 22A is fixed, and the motor stator 6C of the third stage pump unit 1C is in the middle. The diffuser 22B is in contact with the surface opposite to the wall surface to which it is fixed. More specifically, the tip of the annular protrusion 25B of the motor stator 6B is in contact with the outer surface of the bottom wall of the pump casing 2A of the first stage pump unit 1A to which the intermediate diffuser 22A is fixed, and is in contact with the outer surface of the bottom wall of the motor stator 6C. The tip of the annular protrusion 25C is in contact with the outer surface of the bottom wall of the pump casing 2B of the second stage pump unit 1B to which the intermediate diffuser 22B is fixed. With such a configuration, the heat generated in the motor stator 6B is transferred from the protrusion 25B to the intermediate diffuser 22A via the pump casing 2A, and is dissipated from the intermediate diffuser 22A to the handling liquid flowing through the communication flow path 26A. Similarly, the heat generated in the motor stator 6C is transferred from the protrusion 25C to the intermediate diffuser 22B via the pump casing 2B, and is dissipated from the intermediate diffuser 22B to the handling liquid flowing through the communication flow path 26B. As a result, the motor stators 6B and 6C can be efficiently cooled.

As described above, the first-stage diffuser 21 and the intermediate diffusers 22A and 22B also function as heat-dissipating members for transmitting the heat generated by the motor stators 6A, 6B and 6C to the handling liquid and dissipating the heat. As a result, the cooling device (for example, cooling fins or cooling fan) required for the conventional motor pump becomes unnecessary, so that it is possible to suppress an increase in the size of the pump device 100 and an increase in the manufacturing cost. Further, since the upper limit of the temperature of the handling liquid flowing into the pump device 100 can be raised, the operating range of the pump device 100 can be expanded.

The material forming the first-stage diffuser 21 and the intermediate diffusers 22A and 22B is arbitrary. However, the first-stage diffuser 21 and the intermediate diffusers 22A and 22B are preferably formed from a material having a high thermal conductivity in order to efficiently dissipate heat to the handling liquid. For example, the first-stage diffuser 21 and the intermediate diffusers 22A and 22B are formed of a metal such as stainless steel. In one embodiment, the first-stage diffuser 21 and the intermediate diffusers 22A, 22B may be formed of resin.

FIG. 7 is a schematic cross-sectional view of the pump device according to still another embodiment. The pump device 100 shown in FIG. 7 also has a configuration for efficiently cooling the motor stators 6A, 6B, and 6C. Since the configurations not particularly described in this embodiment are the same as those in the above-described embodiment, the duplicated description will be omitted.

The pump units 1A, 1B, and 1C of the pump device 100 shown in FIG. 7 have at least one motor chamber inlet for flowing the handling liquid into the motor chambers 33A, 33B, and 33C instead of the diffusers 21, 22, 22A, and 22B, respectively. It has a hole. In the present embodiment, since the handling liquid flows into the motor chambers 33A, 33B, 33C, the handling liquid has an insulating property so that the stator coils 24A, 24B, 24C of the motor stators 6A, 6B, 6C are not short-circuited. It is a liquid (for example, a fluorine-based insulating liquid).

In one embodiment, a water resistant insulated wire may be used as the winding of the stator coils 24A, 24B, 24C. In this case, even if the handling liquid having conductivity (for example, water) flows into the motor chambers 33A, 33B, 33C, the stator coils 24A, 24B, 24C will not be short-circuited. Water-resistant and insulated electric wires are a general term for electric wires whose windings themselves are liquid-proof (waterproof). The water-resistant insulated wire has, for example, an insulating material layer such as enamel coated on the outer peripheral surface of a conductor such as a copper wire, and a resin layer further coated on the outer peripheral surface of the insulating material layer. This resin layer is made of a resin having excellent water and insulation resistance. Such a resin is, for example, a polyolefin resin (for example, polyethylene, cross-linked polyethylene, polypropylene, etc.).

In one embodiment, the entire winding of each stator coil 24A, 24B, 24C may be molded with an insulating resin. Even in such a configuration, the stator coils 24A, 24B, 24C are not short-circuited by the conductive handling liquid flowing into the motor chambers 33A, 33B, 33C. Further, in this embodiment, as the windings of the stator coils 24A, 24B, 24C, an insulating coated electric wire which is cheaper than the water resistant insulated electric wire can be used.

The first-stage pump unit 1A of the pump device 100 shown in FIG. 7 is formed with an annular opening hole 37A for allowing the handling liquid to flow into the motor chamber 33A. The opening hole 37A allows the motor chamber 33A of the motor casing 3A to communicate with the suction flow path 4c formed in the suction casing 4. Therefore, a part of the handling liquid flowing through the suction flow path 4c of the suction casing 4 flows into the motor chamber 33A through the opening hole 37A and fills the motor chamber 33A. That is, the opening hole 37A functions as a motor chamber inlet hole for allowing the handling liquid sucked from the suction port 4a to flow into the motor chamber 33A. The motor stator 6A is immersed in the handling liquid that has flowed from the suction flow path 4c through the opening hole 37A into the motor chamber 33A.

The heat generated in the motor stator 6A is transferred to the handling liquid that fills the motor chamber 33A, and raises the temperature of the handling liquid. However, during the operation of the pump device 100, the handling liquid in the motor chamber 33A always directly exchanges heat with the lower temperature handling liquid flowing through the suction flow path 4c of the suction casing 4 (see the black arrow in FIG. 7). ), This cools the motor stator 6A.

Similarly, the second-stage pump unit 1B is formed with an annular opening hole (motor chamber inlet hole) 37B for allowing the handling liquid to flow into the motor chamber 33B, and the opening hole 37B allows the motor chamber 33B of the motor casing 3B. Communicates with the communication flow path 26A. An annular opening hole (motor chamber inlet hole) 37C for allowing the handling liquid to flow into the motor chamber 33C is formed in the third stage pump unit 1C, and the motor chamber 33C of the motor casing 3C communicates with the opening hole 37C. Communicate with Road 26B. The handling liquid flows into the motor chamber 33B of the second-stage pump unit 1B and the motor chamber 33C of the third-stage pump unit 1C through the opening holes 37B and 37C, respectively, and the motors in the motor chambers 33B and 33C. The stators 6B and 6C are immersed in the handling liquid. During the operation of the pump device 100, the handling liquid in the motor chambers 33B and 33C always directly exchanges heat with the lower temperature handling liquid flowing through the communication flow paths 26A and 26B, so that the motor stators 6B and 6C are cooled. Will be done.

As described above, in the present embodiment, the motor stators 6A, 6B, 6C are efficiently provided with a simple configuration in which the opening holes (motor chamber inlet holes) 37A, 37B, 37C are provided in the pump units 1A, 1B, 1C. Can be cooled. As a result, the cooling device (for example, cooling fins or cooling fan) required for the conventional motor pump becomes unnecessary, so that it is possible to suppress an increase in the size of the pump device 100 and an increase in the manufacturing cost. Further, since the upper limit of the temperature of the handling liquid flowing into the pump device 100 can be raised, the operating range of the pump device 100 can be expanded.

In the example shown in FIG. 7, the opening hole 37A that functions as the motor chamber inlet hole is one ring-shaped hole that communicates with the suction flow path 4c. However, this embodiment is not limited to this example. For example, as shown in FIG. 8, a plurality of (six in FIG. 8) opening holes 37A functioning as motor chamber inlet holes may be provided on the bottom wall of the casing main body 4b of the suction casing 4. When a plurality of opening holes 37A are provided on the bottom wall of the casing main body 4b, the number, position, cross-sectional shape, and size (for example, diameter) of the opening holes 37A are arbitrary, but the opening holes 37A are provided in the casing main body 4b. It is preferable to arrange them at equal intervals along the circumferential direction. Further, one or a plurality of opening holes 37A that function as motor chamber inlet holes may be communicated with the liquid flow path 3Aa of the motor casing 3A.

Similarly, the plurality of opening holes 37B functioning as the motor chamber inlet holes and the plurality of opening holes 37C functioning as the motor chamber inlet holes are formed on the bottom wall of the pump casing 2A of the first stage pump unit 1A and the second stage pump, respectively. It may be provided on the bottom wall of the pump casing 2B of the unit 1B. The number, position, cross-sectional shape, and size (for example, diameter) of the opening holes 37B are arbitrary, but the plurality of opening holes 37B are preferably arranged at equal intervals along the circumferential direction of the pump casing 2A. .. Similarly, the number, position, cross-sectional shape, and size (eg, diameter) of the opening holes 37C are arbitrary, but the plurality of opening holes 37C are arranged at equal intervals along the circumferential direction of the pump casing 2B. Is preferable. Further, one or more opening holes 37B that function as motor chamber inlet holes may be communicated with the liquid flow path 3Ba of the motor casing 3B, and one or more opening holes 37C that function as motor chamber inlet holes may be communicated with each other. , May communicate with the liquid flow path 3Ca of the motor casing 3C.

In the present embodiment, the guide member 15 described above positively guides the handling liquid that has passed through the suction port 4a so as to pass through the opening hole (motor chamber inlet hole) 37A. Therefore, the guide member 15 always creates a flow of the handling liquid at a low temperature above the opening hole 37A, whereby the motor stator 6A can be efficiently cooled.

FIG. 9 is a schematic cross-sectional view for explaining a modified example of the pump device shown in FIG. 7. FIG. 9 shows an enlarged part of the motor casing 3A of the first stage pump unit 1A. Although not shown, the pump casings 3B and 3C of the pump units 1B and 1C after the first stage pump unit 1A may have the same configuration as that shown in FIG.

As shown in FIG. 9, the motor casing 3A includes an inner cylinder 30A, an outer cylinder 31A arranged radially outside the inner cylinder 30A, and a partition wall 32A connecting the inner cylinder 30A and the outer cylinder 31A. ing. The inner cylinder 30A has a substantially cylindrical shape, and the above-mentioned flow path 3Aa is formed in the central portion thereof. The outer cylinder 31A also has a substantially cylindrical shape, and the partition wall 32A has a ring shape. The partition wall 32A is located between the impeller 14A and the motor stator 6A, and the rotating magnetic field generated by the motor stator 6A reaches the permanent magnet 5A of the impeller 14A through the partition wall 32A.

As shown in FIG. 9, the partition wall 32A is different from the motor casing 3A shown in FIG. 7 in that an opening hole 40A is formed in the partition wall 32A. In order to deepen the understanding of the invention, in FIG. 7, the opening holes 40A (and the opening holes 40B and 40C) shown in FIG. 9 are also shown by dotted lines. The opening hole 40A formed in the partition wall 32A communicates the motor chamber 33A with the accommodation space of the impeller 14A formed in the pump casing 2A.

The pressure of the handling liquid discharged from the impeller 14A is higher than the pressure of the handling liquid before being sucked into the impeller 14A (that is, the handling liquid flowing through the flow paths 4c, 3Aa, 10Aa). Therefore, a part of the handling liquid discharged from the impeller 14A can flow into the motor chamber 33A filled with the handling liquid through the opening hole 40A. That is, in the present embodiment, the opening hole 40A formed in the partition wall 32 allows the handling liquid discharged from the impeller 14A (that is, the handling liquid sucked from the suction port 4a) to flow into the motor chamber 33A. Functions as an entrance hole.

In the present embodiment, the handling liquid that has filled the motor chamber 33A passes through the opening hole 37A and is sucked into the suction casing 4 by the handling liquid that has flowed into the motor chamber 33A through the opening hole (motor chamber inlet hole) 40A. It is pushed out to the road 4c. That is, the above-mentioned opening hole 37A functions as a motor chamber outlet hole of the handling liquid discharged into the suction flow path 4c by the handling liquid flowing into the motor chamber 33 from the opening hole 40A. According to such a configuration, while the impeller 14A is rotating, that is, during the operation of the pump device 100, the handling liquid in the motor chamber 33A is always the low-temperature handling liquid that has flowed in from the opening hole 40A. Can be replaced. Therefore, the motor stator 6A can be cooled more efficiently.

The number of opening holes 40A formed in the partition wall 32 is also arbitrary. For example, the partition wall 32A may have only one annular opening hole 40A, or may have two or more opening holes 40A. When a plurality of opening holes 40A are formed in the partition wall 32A, it is preferable to arrange the opening holes 40A at equal intervals along the circumferential direction of the partition wall 32A. In one embodiment, the number of opening holes 40A matches the number of stator coils 24A, and one opening hole 40A is assigned to each stator coil 24A.

FIG. 10 is a schematic cross-sectional view of the pump device according to still another embodiment. The pump device 100 shown in FIG. 10 has a first-stage pump unit 1A and a second-stage pump unit 1B following the first-stage pump unit 1A. In the present embodiment, the second stage pump unit 1B is a pump unit located at the rearmost stage among the plurality of pump units 1A and 1B. Although not shown, the pump device 100 may have an additional pump unit 1 following the second stage pump unit 1B.

The pump device 100 shown in FIG. 10 is different from the pump device 100 shown in FIG. 7 in that drive circuits 7A and 7B are built in the pump units 1A and 1B, respectively. By incorporating the drive circuits 7A and 7B in the pump device 100, it is not necessary to separately prepare a box body for accommodating the drive circuits 7A and 7B. In addition, maintenance of the pump device 100 becomes easy.

The drive circuit 7A is housed in the circuit casing 27A, and the drive circuit 7B is housed in the circuit casing 27B. Since the circuit casing 7B has the same configuration as the circuit casing 7A described below, the overlapping description will be omitted.

The circuit casing 27A includes an inner cylinder 27Aa, an outer cylinder 27Ab arranged radially outside the inner cylinder 27Aa, and a bottom wall 27Ac connecting the inner cylinder 27Aa and the outer cylinder 27Ab. The inner cylinder 27Aa has a substantially cylindrical shape, and a flow path 27Ad for the handling liquid is formed at the center thereof. The outer cylinder 27Ab also has a substantially cylindrical shape, and the bottom wall 27Ac has a ring shape. The drive circuit 7A is housed in a drive circuit chamber 27Ae surrounded by an inner cylinder 27Aa, an outer cylinder 27Ab, and a bottom wall 27Ac. In the present embodiment, the drive circuit 7A is an inverter device and has a ring shape. Hereinafter, the drive circuit 7A may be referred to as an “inverter device 7A”, the circuit casing 27A may be referred to as an “inverter casing 27A”, and the drive circuit chamber 27Ae may be referred to as an “inverter chamber 27Ae”. Similarly, the drive circuit 7B may be referred to as an "inverter device 7B", the circuit casing 27B may be referred to as an "inverter casing 27B", and the drive circuit chamber 27Be may be referred to as an "inverter chamber 27Be".

The inverter casing 27A is sandwiched between the suction casing 4 and the motor casing 3A, and the suction flow path 4c described above is connected to the flow path 27Ad formed in the inverter casing 27A. The flow path 27Ad is further connected in a row to the flow path 3Aa formed in the motor casing 3A and the flow path 10Aa formed in the bearing 10A. The handling liquid sucked from the suction port 4a and flowing through the suction flow path 4c of the suction casing 4 linearly aligns the flow path 27Ad of the inverter casing 27A, the flow path 3Aa of the motor casing 3A, and the flow path 10Aa of the bearing 10A. It flows and is sucked into the liquid inlet of the impeller 14A.

The inverter device 7A has a power element (for example, a switching element such as an IGBT), and the power element is used to control the timing of the current supplied to the stator coil 24A. The inverter device 7A has a power element module 29A in which power elements are integrated.

When the first stage pump unit 1A is operated, heat is mainly generated from the power element of the inverter device 7A. That is, the main heat generating source of the inverter device 7A is a power element. In the present embodiment, the power elements that are the main heat generating sources of the inverter device 7A are integrated in the power element module 29A.

As shown in FIG. 10, the inverter device 7A is in contact with a surface opposite to the wall surface on which the above-mentioned first-stage diffuser 21 is fixed. More specifically, the power element module 29A of the inverter device 7A is in contact with the outer surface of the bottom wall of the casing main body 4b of the suction casing 4 to which the first stage diffuser 21 is fixed. The heat generated in the inverter device 7A, particularly the power element module 29A, is transferred to the first stage diffuser 21 via the casing main body 4b. Since the first-stage diffuser 21 is in contact with the handling liquid flowing through the suction flow path 4c, the heat transferred from the inverter device 7A to the first-stage diffuser 21 via the casing main body 4b is efficiently dissipated to the handling liquid. As a result, the inverter device 7A can be efficiently cooled.

Further, the motor stator 6A is in contact with the inverter casing 27A. More specifically, the tip of the protrusion 25A of the motor stator 6A is in contact with the outer surface of the bottom wall 27Ac of the inverter casing 27A. The heat generated by the motor stator 6A is transferred from the protrusion 25A to the inverter casing 27A. Since the inverter casing 27A is in contact with the handling liquid flowing through the flow path 27Ad, the heat transferred from the protrusion 25A of the motor stator 6A to the inverter casing 27A is efficiently dissipated to the handling liquid. As a result, the motor stator 6A can be efficiently cooled.

Similarly, the inverter device 7B of the second stage pump unit 1B is in contact with the surface opposite to the wall surface on which the above-mentioned intermediate diffuser 22A is fixed. More specifically, the power element module 29B of the inverter device 7B is in contact with the outer surface of the bottom wall of the pump casing 2A of the first stage pump unit 1A to which the intermediate diffuser 22A is fixed. With such a configuration, the heat generated in the inverter device 7B, particularly the power element module 29B, is transferred to the intermediate diffuser 22A via the motor casing 3A, and is dissipated from the intermediate diffuser 22A to the handling liquid flowing through the communication flow path 26A. NS. As a result, the inverter device 7B can be efficiently cooled.

Further, the tip of the protrusion 25B of the motor stator 6B is also in contact with the outer surface of the bottom wall 27Bc of the inverter casing 27B, and the heat transferred from the protrusion 25B of the motor stator 6B to the inverter casing 27B is transferred to the inverter casing 27B. It is efficiently dissipated to the handling liquid flowing through the flow path 27Bd. As a result, the motor stator 6B can be efficiently cooled.

In the present embodiment, the first-stage diffuser 21 and the intermediate diffuser 22A also function as heat-dissipating members for transmitting the heat generated by the inverter devices 7A and 7B to the handling liquid and dissipating the heat. As a result, the cooling device (for example, cooling fins or cooling fan) required for the conventional motor pump becomes unnecessary, so that it is possible to suppress an increase in the size of the pump device 100 and an increase in the manufacturing cost. Further, since the upper limit of the temperature of the handling liquid flowing into the pump device 100 can be raised, the operating range of the pump device 100 can be expanded.

As shown in FIG. 10, the first-stage pump unit 1A may have heat dissipation fins (radiation member) 50A arranged in the flow path 27Ad of the inverter casing 27A. Similarly, the second-stage pump unit 1B may have heat dissipation fins (radiation member) 50B arranged in the flow path 27Bd of the inverter casing 27B. Since the heat radiating fin 50B has the same configuration as the heat radiating fin 50A, the overlapping description thereof will be omitted.

The heat radiation fin 50A is a plate member that projects from the inner surface of the inner cylinder 27Aa of the inverter casing 27A into the flow path 27Ad. The heat radiating fin 50A can dissipate the heat generated from the inverter device 7A and the motor stator 6A to the handling liquid flowing through the flow path 27Ad via the inner cylinder 27Aa of the inverter casing 27A. Therefore, the radiating fins 50A can more efficiently cool the inverter device 7A and the motor stator 6A.

The heat radiating fin 50A preferably has a high thermal conductivity in order to efficiently dissipate heat to the handling liquid. For example, the radiating fin 50A is made of a metal such as stainless steel.

As shown in FIG. 11, it is preferable that the heat radiation fins 50A are evenly arranged in the circumferential direction of the inner cylinder 27Aa of the inverter casing 27A. FIG. 11 shows an example in which eight heat radiation fins 50A are provided on the inner surface of the inner cylinder 27Aa of the inverter casing 27A, but the number of heat radiation fins 50A is arbitrary.

Further, the heat radiation fin 50A preferably extends parallel to the flow direction of the handling liquid in the flow path 27Ad so as not to disturb the flow of the handling liquid in the flow path 27Ad of the inverter casing 27A. In FIG. 10, the flow direction of the handling liquid in the flow path 27Ad is a direction parallel to the axial direction of the impeller 14A.

FIG. 12 is a schematic cross-sectional view of the pump device according to still another embodiment. The pump device 100 shown in FIG. 12 also has a configuration for efficiently cooling the inverter devices 7A and 7B and the motor stators 6A and 6B. Since the configurations not particularly described in this embodiment are the same as those in the embodiment shown in FIG. 10, the duplicated description will be omitted.

The pump device 100 shown in FIG. 12 has at least one inverter chamber inlet hole for flowing the handling liquid into the inverter chambers 27Ae and 27Be instead of the diffusers 21 and 22A. In the present embodiment, since the handling liquid flows into the inverter chambers 27Ae and 27Be, the handling liquid is an insulating liquid (for example, a fluorine-based insulating liquid) so that the inverter devices 7A and 7B are not short-circuited. ..

In one embodiment, the entire inverter devices 7A and 7B may be molded with an insulating resin. In this case, even if the handling liquid (for example, water) having conductivity flows into the inverter chambers 27Ae and 27Be, the inverter devices 7A and 7B will not be short-circuited.

In the present embodiment as well, unless otherwise specified, the inverter casing 7B has the same configuration as the inverter casing 7A described below, and thus the duplicate description thereof will be omitted.

The first-stage pump unit 1A shown in FIG. 12 is formed with a plurality of opening holes 53A for allowing the handling liquid to flow into the inverter chamber 27Ae. More specifically, the plurality of opening holes 53A are formed in the bottom wall of the casing main body 4b of the suction casing 4. The plurality of opening holes 53A are preferably arranged at equal intervals along the circumferential direction of the suction casing 4. The opening hole 53A allows the inverter chamber 27Ae of the inverter casing 27A to communicate with the suction flow path 4c of the suction casing 4. Therefore, a part of the handling liquid flowing through the suction flow path 4c of the suction casing 4 flows into the inverter chamber 27Ae through the opening hole 53A and fills the inverter chamber 27Ae. That is, the opening hole 53A functions as an inverter chamber inlet hole for allowing the handling liquid sucked from the suction port 4a to flow into the inverter chamber 27Ae. The inverter device 7A is immersed in the handling liquid that has flowed from the suction flow path 4c through the opening hole 53A into the inverter chamber 27Ae.

The heat generated in the inverter device 7A is transferred to the handling liquid that fills the inverter chamber 27Ae, and raises the temperature of the handling liquid. However, during the operation of the pump device 100, the handling liquid in the inverter chamber 27Ae always directly exchanges heat with the lower temperature handling liquid flowing through the suction flow path 4c of the suction casing 4, whereby the inverter device 7A can perform heat exchange. It is cooled.

Further, since the tip of the protrusion 25A of the motor stator 6A is in contact with the outer surface of the bottom wall of the inverter casing 27A, the heat generated by the motor stator 6A is transferred from the protrusion 25A to the inverter casing 27A. Since the inside of the inverter chamber 27Ae of the inverter casing 27A is filled with the handling liquid, the heat transferred from the protrusion 25A of the motor stator 6A to the inverter casing 27A is efficiently dissipated to the handling liquid in the inverter chamber 27Ae. As a result, the motor stator 6A can be efficiently cooled.

Similarly, in the second stage pump unit 1B, a plurality of opening holes (inverter chamber inlet holes) 53B for flowing the handling liquid into the inverter chamber 27Be are formed, and the opening holes 53B form the inverter chamber 27Be of the inverter casing 27B. Communicates with the communication flow path 26A of the first stage pump unit 1A. The handling liquid flows into the inverter chamber 27Be of the second stage pump unit 1B through the opening hole 53B, and the inverter device 7B in the inverter chamber 27Be is immersed in the handling liquid. During the operation of the pump device 100, the handling liquid in the inverter chamber 27Be always directly exchanges heat with the lower temperature handling liquid flowing through the communication flow path 26A, so that the inverter device 7B is cooled. Further, since the tip of the protrusion 25B of the motor stator 6B is in contact with the outer surface of the bottom wall of the inverter casing 27B, the heat generated in the motor stator 6B is transferred from the protrusion 25B to the inside of the inverter chamber 27Be via the inverter casing 27B. Efficiently dissipates to the handling liquid of. As a result, the motor stator 6B can be efficiently cooled.

In the embodiment shown in FIG. 12, the first-stage pump unit 1A has a plurality of opening holes 53A that communicate with the suction flow path 4c and function as inverter chamber inlet holes, but the present embodiment is not limited to this example. .. For example, the first stage pump unit 1A may have one opening hole 53A that functions as an inverter chamber inlet hole. Further, one or more opening holes 53A that function as inverter chamber inlet holes may communicate with the flow path 27Ae of the inverter casing 27A.

Similarly, the second-stage pump unit 1B has a plurality of opening holes 53B that communicate with the communication flow path 26A and function as inverter chamber inlet holes, but the present embodiment is not limited to this example. For example, the first stage pump unit 1B may have one opening hole 53B that functions as an inverter chamber inlet hole. Further, one or a plurality of opening holes 53B that function as inverter chamber inlet holes may be communicated with the flow path 27Be of the inverter casing 27B.

As described above, in the present embodiment, the inverter devices 7A and 7B and the motor stators 6A and 6B are made efficient by providing the opening holes (inverter chamber inlet holes) 53A and 53B in the pump units 1A and 1B. Can be cooled. As a result, the cooling device (for example, cooling fins or cooling fan) required for the conventional motor pump becomes unnecessary, so that it is possible to suppress an increase in the size of the pump device 100 and an increase in the manufacturing cost. Further, since the upper limit of the temperature of the handling liquid flowing into the pump device 100 can be raised, the operating range of the pump device 100 can be expanded.

In the embodiment shown in FIG. 12, the guide member 15 described above positively guides the handling liquid that has passed through the suction port 4a so as to pass through the opening hole (inverter chamber inlet hole) 53A. Therefore, the guide member 15 always creates a flow of the handling liquid having a low temperature above the opening hole 53A, whereby the inverter device 7A and the motor stator 6A can be efficiently cooled. Further, the entire inverter device 7A can be directly cooled by the handling liquid filled in the inverter chamber 27Ae of the inverter casing 27A. Therefore, the inverter device 7A may have the power element module 29A arranged inside the inverter device 7A. Similarly, the inverter device 7B may have the power element module 29B arranged inside the inverter device 7B.

FIG. 13 is a schematic cross-sectional view for explaining a modified example of the pump device shown in FIG. FIG. 13 shows an enlarged view of the inverter casing 27A and the motor casing 3A of the first stage pump unit 1A. Although not shown, the inverter casing 27B and the motor casing 3B of the pump unit 1B after the first stage pump unit 1A may have the same configuration as that shown in FIG. Since the configuration of the present embodiment, which is not particularly described, is the same as the configuration of the pump device 100 shown in FIG. 12, the duplicate description thereof will be omitted.

In the embodiment shown in FIG. 13, a plurality of opening holes 53A that function as inverter chamber inlet holes are formed in the inner cylinder 27Aa of the inverter casing 27A. The handling liquid flowing through the flow path 27Ad of the inverter casing 27A flows into the inverter chamber 27Ae.

Further, at least one opening hole 54A is formed in the bottom wall 27Ac of the inverter casing 27A. As shown in FIG. 13, the motor casing 3A is connected to the inverter casing 27A. More specifically, the motor casing 3A is connected to the bottom wall 27Ac of the inverter casing 27A. Therefore, the opening hole 54A allows the motor chamber 33A to communicate with the inverter chamber 27Ae. The opening hole 54A formed in the bottom wall 27Ac functions as at least one communication hole for allowing the handling liquid in the inverter chamber 27Ae to flow into the motor chamber 33A of the motor casing 3A.

The heat generated in the motor stator 6A is transferred to the handling liquid flowing into the motor chamber 33A through the communication hole 54A, and further to the handling liquid in the inverter chamber 27Ae. However, since the handling liquid in the inverter chamber 27Ae always directly exchanges heat with the lower temperature handling liquid flowing through the flow path 27Ad of the inverter casing 27A, the inverter device 7A and the motor stator 6A should be cooled efficiently. Can be done. In the present embodiment, the entire motor stator 6A is cooled by the handling liquid that fills the motor chamber 33A. Therefore, the protrusion 25A of the motor stator 6A can be omitted.

Instead of the opening hole 54A that functions as a communication hole, the above-mentioned opening hole 37A (see the dotted line in FIG. 13) may be provided in the inner cylinder 30A of the motor casing 3A. The opening hole 37A functions as a motor chamber inlet hole for allowing the handling liquid flowing through the flow path 3Aa of the motor casing 3A to flow into the motor chamber 33A. In this case, the inverter chamber 27Ae is filled with the handling liquid flowing from the flow path 27Ad of the inverter casing 27A through the opening hole 53A, and the motor chamber 33A is handled to flow in from the flow path 3Aa of the motor casing 3A through the opening hole 37A. Filled with liquid.

In one embodiment, the opening hole 40A may be formed in the partition wall 32A of the motor casing 3A. As described above, the pressure of the handling liquid discharged from the impeller 14A is higher than the pressure of the handling liquid before being sucked into the impeller 14A (that is, the handling liquid flowing through the flow paths 4c, 27Ad, 3Aa, 10Aa). .. Therefore, a part of the handling liquid discharged from the impeller 14A can flow into the motor chamber 33A filled with the handling liquid through the opening hole 40A, and further into the inverter chamber 27Ae. That is, also in the present embodiment, the opening hole 40A formed in the partition wall 32A allows the handling liquid discharged from the impeller 14A (that is, the handling liquid sucked from the suction port 4a) to flow into the motor chamber 33A. Functions as an entrance hole.

The handling liquid that has flowed into the motor chamber 33A through the opening hole (motor chamber inlet hole) 40A pushes the handling liquid that fills the motor chamber 33A into the inverter chamber 27Ae of the inverter casing 27A through the communication hole 54A. The handling liquid that has flowed into the inverter chamber 27Ae through the communication hole 54A pushes the handling liquid that fills the inverter chamber 27Ae into the flow path 27Ad of the inverter casing 27A through the opening hole 53A. That is, the above-mentioned opening hole 53A functions as an inverter chamber outlet hole of the handling liquid discharged into the flow path 27Ad of the inverter casing 27A by the handling liquid flowing into the inverter chamber 27Ae from the communication hole 54A. According to such a configuration, while the impeller 14A is rotating, that is, during the operation of the pump device 100, the handling liquid in the motor chamber 33A and the inverter chamber 27Ae always flows in from the opening hole 40A at a low temperature. It can be replaced with the handling liquid of. Therefore, the motor stator 6A and the inverter device 7A can be cooled more efficiently.

As shown in FIG. 14, the inverter casing 27A may have a large opening hole 54A in which the opening hole 54A is connected to the opening hole 53A. With such a configuration, the first stage pump unit 1A can be provided with a large opening hole capable of simultaneously and easily guiding the handling liquid to the inverter chamber 27Ae and the motor chamber 33A.

FIG. 15 is a schematic cross-sectional view for explaining another modification of the pump device shown in FIG. Since the configuration of the present embodiment, which is not particularly described, is the same as that of the embodiment shown in FIG. 13, the duplicated description will be omitted.

In the embodiment shown in FIG. 15, at least one opening hole (inverter chamber inlet hole) 53A of the inverter casing 27A is opened in the flow path 4c formed in the suction casing 4. Through the opening hole 53A, the inverter chamber 27Ae of the inverter casing 27A communicates with the flow path 4c, and the handling liquid flowing through the flow path 4c flows into the inverter chamber 27Ae. The inverter chamber 27Ae is filled with the handling liquid that has flowed in from the flow path 4c through the opening hole 53A.

Further, the handling liquid that has flowed into the inverter chamber 27Ae flows into the motor chamber 33A through the opening hole (communication hole) 54A and fills the motor chamber 33A. In the present embodiment, the handling liquid in the inverter chamber 27Ae always directly exchanges heat with the lower temperature handling liquid flowing through the flow path 4c of the suction casing 4, so that the inverter device 7A and the motor stator 6A are efficiently exchanged. Can be cooled.

Similar to the embodiment described with reference to FIG. 13, the above-mentioned opening hole 37A (see the dotted line in FIG. 15) is provided in the inner cylinder 30A of the motor casing 3A instead of the opening hole 54A that functions as a communication hole. May be good. The opening hole 37A functions as a motor chamber inlet hole for allowing the handling liquid flowing through the flow path 3Aa of the motor casing 3A to flow into the motor chamber 33A.

Further, the opening hole 40A may be formed in the partition wall 32A of the motor casing 3A. In this case, the opening hole 40A formed in the partition wall 32A functions as a motor chamber inlet hole for allowing the handling liquid discharged from the impeller 14A (that is, the handling liquid sucked from the suction port 4a) to flow into the motor chamber 33A. do. A part of the handling liquid discharged from the impeller 14A may flow into the motor chamber 33A filled with the handling liquid through the opening hole 40A, and further flow into the inverter chamber 27Ae through the opening hole 54A. can.

The handling liquid that has flowed into the motor chamber 33A through the opening hole (motor chamber inlet hole) 40A pushes the handling liquid that fills the motor chamber 33A into the inverter chamber 27Ae of the inverter casing 27A through the communication hole 54A. The handling liquid that has flowed into the inverter chamber 27Ae through the communication hole 54A pushes the handling liquid that fills the inverter chamber 27Ae into the flow path 27Ad of the inverter casing 27A through the opening hole 53A. Therefore, when the opening hole 40A is provided in the partition wall 32A of the motor casing 3A, the above-mentioned opening hole 53A is discharged to the flow path 27Ad of the inverter casing 27A by the handling liquid flowing into the inverter chamber 27Ae from the communication hole 54A. Functions as an outlet hole for the liquid inverter chamber. According to such a configuration, while the impeller 14A is rotating, that is, during the operation of the pump device 100, the handling liquid in the motor chamber 33A and the inverter chamber 27Ae always flows in from the opening hole 40A at a low temperature. It can be replaced with the handling liquid of. Therefore, the motor stator 6A and the inverter device 7A can be cooled more efficiently.

FIG. 16 is a schematic view showing an example of a water supply device equipped with the pump device 100 according to the above-described embodiment. The water supply device is a device for supplying water to a building such as an office building or a condominium.

The water supply device 200 shown in FIG. 16 includes a pump device 100 according to the above-described embodiment. In the present embodiment, the control unit 8 described above is used as a control unit that controls the operation of the entire water supply device 200. The suction port 4a of the suction casing 4 of the first stage pump unit 1A of the pump device 100 is connected to the water main 209 via a suction pipe 219. The discharge port 16 formed in the pump unit 1C located at the rearmost stage of the pump device 100 is connected to the water supply pipe 207 via the drain pipe 220. The water supply pipe 207 communicates with a water faucet (faucet or the like) of a building (not shown).

Although the drive circuits 7A, 7B, and 7C for adjusting the operating speed of the pump units 1A, 1B, and 1C are omitted in FIG. 16, these drive circuits 7A, 7B, and 7C are the pump units 1A, 1B, respectively. , 1C may be arranged outside (see FIGS. 3 (a) to 3 (c)), or may be built in each of the pump units 1A, 1B, 1C (FIGS. 10, 12, and FIG. 13, FIG. 14, and FIG. 15).

The water supply device 200 of the present embodiment is configured to supply water to each faucet of the building by using the pressure of the water main 209 and increasing the pressure as needed. This type of water supply device 200 is called a direct connection type water supply device because the suction side is directly connected to the water main 209. However, the present invention is not limited to the present embodiment, and the water supply device 200 may be a water receiving tank type water supply device in which the suction side is connected to the water receiving tank.

The water supply device 200 shown in FIG. 16 is arranged on the discharge side of the pump device 100 having a plurality of pump units 1A, 1B, 1C for pressurizing water and the pump unit 1C located at the rearmost stage of the pump device 100. It includes a check valve 222, a flow switch 224 arranged on the discharge side of the check valve 222, a discharge pressure sensor 226 arranged on the discharge side of the flow switch 224, and a pressure tank 223.

The check valve 222 and the flow switch 224 are attached to the drain pipe 220. The discharge pressure sensor 226 and the pressure tank 223 are connected to the drain pipe 220. The check valve 222 is a valve for preventing backflow of water when all of the plurality of pump units 1A, 1B, and 1C are stopped. The flow switch 224 is a flow rate detector that detects the flow rate of water flowing through the plurality of pump units 1A, 1B, and 1C. The flow switch 224 in the present embodiment detects that the flow rate of the water discharged from the plurality of pump units 1A, 1B, 1C has decreased to a predetermined value or less. In one embodiment, the flow switch 224 may detect the flow rate of water flowing into the plurality of pump units 1A, 1B, 1C.

The discharge pressure sensor 226 is a water pressure measuring device for measuring the discharge pressures of a plurality of pump units 1A, 1B, 1C. The pressure tank 223 is a pressure retainer for holding the discharge pressure while the plurality of pump units 1A, 1B, and 1C are stopped.

Power lines (lead wires) 17A, 17B, and 17C extending from the power supply (commercial power supply) 9 are connected to the pump units 1A, 1B, and 1C, respectively. Earth Leakage Circuit Breaker (ELB) 238 is provided on each of the power lines 17A, 17B, and 17C.

Although not shown, when the drive circuits 7A, 7B, and 7C are arranged outside the pump units 1A, 1B, and 1C, the drive circuits 7A, 7B, and 7C are the earth-leakage circuit breakers 238 and the pump units 1A, respectively. , 1B, 1C are arranged on the power lines 17A, 17b, 17C.

The pump units 1A, 1B and 1C have temperature sensors 18A, 18B and 18C for measuring the temperature of the pump units 1A, 1B and 1C, respectively. As shown in FIGS. 9, 12, 13, 14, and 15, the temperature sensor 18A is attached to, for example, the motor stator 6A. Similarly, the temperature sensors 18B and 18C are also attached to the motor stators 6B and 6C, respectively. The temperature sensors 18A, 18B, 18C send the measured values to the control unit 8.

Further, as shown in FIGS. 9, 12, 13, 14, and 15, the first-stage pump unit 1A may have a vibration sensor 20A that detects the vibration of the first-stage pump unit 1A. The vibration sensor 20A detects the vibration generated during the operation of the first stage pump unit 1A. The vibration sensor 20A is, for example, a sensor capable of detecting the amplitude (magnitude), direction, and / or acceleration of vibration. In the present embodiment, the vibration sensor 20A is arranged in the inner cylinder 30A of the motor casing 3A and is connected to the control unit 8. The vibration sensor 20A sends the measured value to the control unit 8. Similarly, the second-stage pump unit 1B and the third-stage pump unit 1C also measure the vibration generated during the operation of the second-stage pump unit 1B and the vibration generated during the operation of the third-stage pump unit 1C, respectively. It may have a vibration sensor. These vibration sensors are also connected to the control unit 8 and send the measured values to the control unit 8.

The control unit 8 is a first storage device 227 that stores various set values required for the operation of the water supply device 200 and a program, and a processing device that executes an operation according to an instruction included in the program stored in the first storage device 227. (For example, CPU) 228 is provided. The flow switch 224, the discharge pressure sensor 226, and the temperature sensors 18A, 18B, 18C are connected to the control unit 8 by a signal line. When the vibration sensors (see the vibration sensors 20A shown in FIGS. 9, 12, 13, 14, and 15) are provided in the pump units 1A, 1B, and 1C, respectively, these vibration sensors are also controlled by signal lines. Connected to 8.

The drive circuits 7A, 7B, 7C of each pump unit 1A, 1B, 1C are connected to the control unit 8 by a communication line 230. One end of the communication line 230 is connected to the communication port 226 of the control unit 8. The other end of the communication line 230 is branched according to the number of pump units 1A, 1B, 1C provided in the pump device 100, and is connected to each drive circuit 7A, 7B, 7C. The control unit 8 and the drive circuits 7A, 7B, and 7C communicate with each other for transmitting and receiving various commands and various set values.

The control unit 8 supplies water by automatic operation described below. In automatic operation, the plurality of pump units 1A, 1B, 1C are controlled by the control unit 8 so that the first stage pump unit 1A is started first, and then the remaining pump units 1B, 1C are basically started alternately. Will be done. When all of the plurality of pump units 1A, 1B, and 1C are stopped, the first stage pump unit 1A is stopped at the end. The control unit 8 controls the operation of the pump units 1B and 1C so that the number of operations and the stop time of the pump units 1B and 1C other than the first stage pump unit 1A are equalized. The control unit 8 may store the number of pump units other than the first-stage pump unit 1A and the number of pump units operated in parallel as set values required for the operation of the water supply device 200.

Next, an example of the operation operation of the water supply device 200 will be described with reference to FIGS. 17 and 18. FIG. 17 is a flowchart for explaining an example of the starting operation of the pump device 100 mounted on the water supply device 200 shown in FIG. 16, and FIG. 18 is a flowchart of the pump device 100 mounted on the water supply device 200 shown in FIG. It is a flowchart for demonstrating an example of the stop operation of.

As shown in FIG. 17, when all the pump units 1A, 1B, and 1C are in the stopped state, the control unit 8 monitors whether or not a predetermined starting condition is satisfied (see step 1). For example, the control unit 8 monitors whether or not the discharge pressure measured by the discharge pressure sensor 226 is equal to or lower than a predetermined starting pressure. If the water in the building is used while all the pump units 1A, 1B, 1C are stopped, the water held in the pressure tank 223 is supplied to the building. The pressure tank 223 acts to prevent frequent start-ups and stops of the pump units 1A, 1B, and 1C, and to keep the change in the water supply pressure smooth. As more water is used in the building, the water in the pressure tank 223 is reduced, resulting in a discharge pressure below a predetermined starting pressure. The control unit 8 stores a predetermined starting pressure in advance, and determines that the predetermined starting condition is satisfied when the discharge pressure drops to the predetermined starting pressure or less.

When a predetermined starting condition is satisfied (see YES in step 1), the control unit 8 first starts the first stage pump unit 1A (see step 2). The reason for this is that the first-stage pump unit 1A has a suction performance capable of transferring the handling liquid to the second-stage pump unit 1B following the first-stage pump unit 1A at a desired flow rate. The control unit 8 may store the operating speed of the first-stage pump unit 1A at the time of starting as a set value required for operating the water supply device 200.

During the operation of the first stage pump unit 1A, the control unit 8 executes the estimated terminal pressure constant control or the discharge pressure constant control based on the measured value of the discharge pressure sent from the discharge pressure sensor 226. In the constant discharge pressure control, the discharge pressure is constantly controlled so as to maintain a predetermined target value (set pressure). By appropriately changing the target value of the discharge pressure by controlling the estimated terminal pressure to be constant, the water pressure (terminal pressure) at the terminal faucet in the building maintains a predetermined pressure (set pressure). To control.

If the demand for water at the water supply destination increases during the operation of the first stage pump unit 1A, the control unit 8 additionally operates one of the standby pump units 1B and 1C. Specifically, the control unit 8 monitors whether or not the conditions for determining whether or not to additionally operate the next pump unit are satisfied after starting the first stage pump unit 1A (step 3). reference). Hereinafter, the conditions for determining whether or not to additionally operate the next pump unit will be referred to as "next pump unit starting conditions". The control unit 8 stores in advance the next pump unit start condition as a set value required for the operation of the water supply device 200.

The next pump unit starting condition is, for example, the operating speed of the first stage pump unit 1A or the discharge pressure measured by the discharge pressure sensor 226. If the demand for water at the water supply destination increases during the operation of the first-stage pump unit 1A, the operating speed of the first-stage pump unit 1A increases. The control unit 8 stores in advance the threshold value of the operating speed of the first stage pump unit 1A as the starting condition of the next pump unit. When the operating speed of the first-stage pump unit 1A exceeds the threshold value, the control unit 8 determines that the next pump unit start condition is satisfied.

Alternatively, the control unit 8 may store the threshold value of the discharge pressure in advance as the start condition of the next pump unit. If the demand for water at the water supply destination increases during the operation of the first stage pump unit 1A, the discharge pressure decreases. The control unit 8 determines that the next pump unit start condition is satisfied when the discharge pressure drops below the threshold value.

When the next pump unit start condition is satisfied (see YES in step 3), the control unit 8 starts the next pump unit (see step 4). The next pump unit is a pump unit different from the first stage pump unit 1A, and in the water supply device shown in FIG. 16, it is the second stage pump unit 1B or the third stage pump unit 1C. The control unit 8 selects either the second stage pump unit 1B or the third stage pump unit 1C as the next pump unit so that the pump units 1B and 1C are started alternately, and starts the next pump unit. ..

Even during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C), the control unit 8 controls the estimated end pressure constant control or the discharge pressure constant control based on the measured value of the discharge pressure sent from the discharge pressure sensor 226. To execute.

When the demand for water at the water supply destination further increases, the control unit 8 additionally operates the standby pump unit 1C (or 1B). Specifically, whether or not the condition for determining whether or not the control unit 8 additionally operates the pump units one after another after starting the first stage pump unit 1A and the second pump unit 1B (or 1C) is satisfied. Is being monitored (see step 5). Hereinafter, the conditions for determining whether or not to additionally operate the pump units one after another are referred to as "one after another pump unit starting conditions". The control unit 8 stores the pump unit start conditions one after another as set values necessary for the operation of the water supply device 200 in advance.

The pump unit starting conditions one after another are, for example, the operating speed of the next pump unit 1B (or 1C), or the discharge pressure measured by the discharge pressure sensor 226. If the demand for water at the water supply destination increases during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C), the operating speed of the next pump unit 1B (or 1C) increases. The control unit 8 stores in advance the threshold value of the operating speed of the next pump unit 1B (or 1C) as a pump unit starting condition one after another. When the operating speed of the next pump unit 1B (or 1C) exceeds the threshold value, the control unit 8 determines that the pump unit start conditions are satisfied one after another.

Alternatively, similarly to the next pump unit starting condition, the control unit 8 may store the threshold value of the discharge pressure in advance as the pump unit starting condition one after another. If the demand for water at the water supply destination increases during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C), the discharge pressure decreases. The control unit 8 determines that the pump unit start conditions are satisfied one after another when the discharge pressure drops below the threshold value.

When the pump unit start conditions are satisfied one after another (see YES in step 5), the control unit 8 starts the pump units one after another (see step 6). The pump units one after another are different pump units from the first stage pump unit 1A and the next pump unit. In the water supply device 200 shown in FIG. 16, when the next pump unit is the pump unit 1B (or 1C), the pump units are the pump unit 1C (or 1B) one after another.

Even during the operation of the first stage pump unit 1A, the second pump unit 1B (or 1C), and the pump unit 1C (or 1B) one after another, the control unit 8 is based on the measured value of the discharge pressure sent from the discharge pressure sensor 226. Performs estimated end pressure constant control or discharge pressure constant control.

Next, the stop operation of the pump device 100 will be described with reference to FIG. When the demand for water at the water supply destination decreases while all the pump units 1A, 1B, and 1C are in operation, the control unit 8 stops the operation of the pump units 1C (or 1B) one after another. Specifically, the control unit 8 satisfies the condition for determining whether or not to stop the pump units 1C (or 1B) one after another after all the pump units 1A, 1B, and 1C have started the operation. Whether or not it is monitored (see step 7). Hereinafter, the condition for determining whether or not to stop the pump units 1C (or 1B) one after another is referred to as "one after another pump unit stop condition". The control unit 8 stores the pump unit stop conditions one after another as set values necessary for the operation of the water supply device 200 in advance.

The pump unit stop operation condition one after another is, for example, the operating speed of the pump unit 1C (or 1B) one after another, or the discharge pressure measured by the discharge pressure sensor 226. If the demand for water at the water supply destination decreases during the operation of all the pump units 1A, 1B, 1C, the operating speed of the pump units 1C (or 1B) decreases one after another. The control unit 8 stores in advance the threshold value of the operating speed of the pump units 1C (or 1B) one after another as a condition for stopping the pump units one after another. The control unit 8 determines that the pump unit stop condition is satisfied one after another when the operating speed of the pump units 1C (or 1B) is lowered below the threshold value one after another.

Alternatively, the control unit 8 may store the threshold value of the discharge pressure in advance as a pump unit stop condition one after another. If the demand for water at the water supply destination decreases during the operation of all the pump units 1A, 1B, 1C, the discharge pressure increases. The control unit 8 determines that the pump unit stop condition is satisfied one after another when the discharge pressure increases from the threshold value. When the pump unit stop conditions are satisfied one after another (see YES in step 7), the control unit 8 stops the pump units 1C (or 1B) one after another (see step 8).

After stopping the pump units 1C (or 1B) one after another (that is, during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C)), when the demand for water at the water supply destination further decreases, the control unit 8 stops the next pump unit 1B (or 1C). Specifically, the control unit 8 monitors whether or not the conditions for determining whether or not to stop the next pump unit are satisfied after stopping the pump units 1C (or 1B) one after another. Yes (see step 9). Hereinafter, the condition for determining whether or not to stop the next pump unit 1B (or 1C) is referred to as a "next pump unit stop condition". The control unit 8 stores in advance the next pump unit stop condition as a set value required for the operation of the water supply device 200.

The next pump unit stop condition is, for example, the operating speed of the next pump unit 1B (or 1C) or the discharge pressure measured by the discharge pressure sensor 226. If the demand for water at the water supply destination decreases during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C), the operating speed of the next pump unit 1B (or 1C) decreases. The control unit 8 stores in advance the threshold value of the operating speed of the next pump unit 1B (or 1C) as a condition for stopping the next pump unit. When the operating speed of the next pump unit 1B (or 1C) becomes lower than the threshold value, the control unit 8 determines that the next pump unit stop condition is satisfied.

Alternatively, similarly to the pump unit stop condition one after another, the control unit 8 may store the threshold value of the discharge pressure in advance as the next pump unit stop condition. When the demand for water at the water supply destination decreases during the operation of the first stage pump unit 1A and the second pump unit 1B (or 1C), the discharge pressure increases. The control unit 8 determines that the next pump unit stop condition is satisfied when the discharge pressure rises above the threshold value. When the next pump unit stop condition is satisfied (see YES in step 9), the control unit 8 stops the next pump unit 1B (or 1C) (see step 10).

After stopping the next pump unit 1B (or 1C) (that is, while operating only the first stage pump unit 1A), if the use of water at the water supply destination is further reduced (for example, the use of water at the water supply destination) When stopped), the control unit 8 stops the first stage pump unit 1A. Specifically, the control unit 8 monitors whether or not a predetermined condition for determining whether or not to stop the first stage pump unit 1A is satisfied after stopping the next pump unit 1B. (See step 11). Hereinafter, a predetermined condition for determining whether or not to stop the first stage pump unit 1A is referred to as a “total stop condition”. The control unit 8 stores all the stop conditions in advance as set values required for the operation of the water supply device 200.

The all stop condition is, for example, the presence or absence of reception of the underflow detection signal transmitted from the flow switch 224. As the use of water at the water supply destination decreases, the flow rate of water flowing through the plurality of pump units 1A, 1B, 1C decreases. When the flow switch 224 detects that the flow rate of water flowing through the plurality of pump units 1A, 1B, 1C has dropped to a predetermined value or less (underflow rate), the flow switch 224 sends an underflow rate detection signal to the control unit 8. When the control unit 8 receives this underflow detection signal, the control unit 8 determines that the all stop condition is satisfied.

Alternatively, the control unit 8 may store the threshold value of the discharge pressure in advance as a total stop condition. If the demand for water at the water supply destination decreases during the operation of the first stage pump unit 1A, the discharge pressure increases. The control unit 8 determines that the all stop condition is satisfied when the discharge pressure rises above the threshold value.

When all the stop conditions are satisfied (see YES in step 11), the control unit 8 performs an accumulator operation for temporarily increasing the rotation speed of the first stage pump unit 1A until the discharge pressure reaches a predetermined stop pressure, and the pressure tank is operated. After accumulating pressure at 223, the first stage pump unit 1A is stopped. Such a stop operation of the first stage pump unit 1A is called a small water amount stop operation. Further, a state in which all the pump units 1A, 1B, and 1C are stopped by the small water amount stop operation is referred to as a small water amount stop state.

After stopping the next pump unit 1B (or 1C) (that is, after step 10), when the next pump unit start condition is satisfied (see Yes in step 3), the control unit 8 again performs the next pump unit. Start 1B (or 1C) (see step 4). Similarly, after the pump units 1C (or 1B) are stopped one after another (that is, after step 8), when the pump unit start conditions are satisfied one after another (see Yes in step 5), the control unit 8 again performs the control unit 8. The pump units 1C (or 1B) are started one after another (see step 6).

As described above, in the automatic operation control of the pump device 100 of the water supply device 200, the first stage pump unit 1A is started first when a predetermined starting condition is satisfied. Further, the first stage pump unit 1A continues its operation until a predetermined stop condition is satisfied after the other pump units 1B and 1C are stopped. That is, the first stage pump unit 1A is finally stopped.

As shown in FIG. 16, the control unit 8 has a pressure signal input terminal 233 to which a signal line extending from the discharge pressure sensor 226 is connected, a flow rate signal input terminal 234 to which a signal line extending from the flow switch 224 is connected, and a temperature. It is provided with a temperature signal input terminal 235 to which a signal line extending from each of the sensors 18 is connected. The measured value of the discharge pressure, the underflow detection signal, and the measured value of the temperature of each pump unit 1 are measured by the processing device 228 of the control unit 8 through the pressure signal input terminal 233, the flow signal input terminal 234, and the temperature signal input terminal 235. It is designed to be entered in. When the measured value of the temperature of the pump unit 1 sent from the temperature sensor 18 exceeds the upper limit value, the control unit 8 abnormally stops the operation of the corresponding pump unit 1 on the assumption that an abnormality of pump overheating is detected. ..

In the present embodiment, abnormal stop means forcibly making the pump unit 1 in which an abnormality has occurred into an inoperable state. Specifically, when the operating pump unit 1 is abnormally stopped, the operation of the pump unit 1 is stopped. When the stopped pump unit 1 is abnormally stopped, the stopped state of the pump unit 1 is maintained and the pump unit 1 cannot be started.

The control unit 8 is connected to a power line 242 branching from a power line extending from the power supply 9, and power is supplied to the control unit 8 through the power line 242. The control unit 8 includes a power switch 243, and when the power switch 243 is turned on, electric power is supplied to the control unit 8 through the power line 242. The control unit 8 sets an operation signal which is an ON / OFF signal indicating whether or not each pump unit 1 is in operation (starting and stopping of each pump unit 1) and a failure signal indicating a failure of each pump unit 1 or the like. It is further provided with an output terminal 245 for outputting to the outside.

The control unit 8 further includes a trip signal input terminal 239 to which a signal line extending from each earth-leakage circuit breaker 238 is connected. When the earth-leakage circuit breaker 238 detects the earth leakage, the earth-leakage circuit breaker 238 issues a trip signal to the control unit 8. This trip signal is input to the processing device 228 of the control unit 8 through the trip signal input terminal 239. When the control unit 8 receives the trip signal from the earth leakage circuit breaker 238, the control unit 8 determines that the abnormality has been detected and abnormally stops the operation of the corresponding pump unit 1.

Further, a current sensor (current detecting means) 251 is arranged on each of the power lines 17A, 17B, 17C for supplying a current to the drive circuits 7A, 7B, 7C. These current sensors 251 measure the current value flowing through each pump unit 1. These current sensors 251 are also connected to the control unit 8 and send the measured values of the currents flowing through the power lines 17A, 17B, 17C to the control unit 8. In FIG. 16, the signal line extending from the current sensor 251 to the control unit 8 is omitted in order to avoid complicating the figure. The current value supplied to each pump unit 1 measured by the current sensor 251 is also input to the processing device 228 of the control unit 8. When the drive circuits 7A, 7B, and 7C are inverter devices, the magnitude of the current supplied from the drive circuits 7A, 7B, and 7C to each pump unit 1 is sent to the control unit 8 and sent to the processing device 228. Entered.

The control unit 8 stores in advance the limit value of the current supplied to each pump unit 1, and detects an overcurrent abnormality when the measured value of the current supplied to each pump unit 1 exceeds the limit value. If so, the corresponding pump unit 1 is abnormally stopped.

Further, when the pump device 100 has a vibration sensor 20 for measuring the vibration of each pump unit 1, these vibration sensors 20 are also connected to the control unit 8 and send the measured value of the vibration to the control unit 8. The measured value of vibration sent to the control unit 8 is also input to the processing device 228.

The operating state of each pump unit 1 (whether or not the pump unit 1 is operating normally) can be determined based on the vibration generated in the pump unit 1 during operation. For example, if a defect occurs in the impeller 14 and / or the bearing 10, the amplitude and acceleration of the vibration generated in the pump unit 1 become large. Therefore, when the measured value of vibration (measured value of vibration amplitude, direction, and / or acceleration) transmitted from the vibration sensor 20 exceeds a predetermined threshold value, the control unit 8 detects a vibration abnormality. As a result, the corresponding pump unit 1 is abnormally stopped.

In this way, the control unit 8 is configured to be able to detect the abnormality generated in each pump unit 1 for each pump unit 1. The control unit 8 abnormally stops only the pump unit 1 in which the abnormality has occurred among the plurality of pump units 1A, 1B, and 1C. Since the water supply device 200 that supplies water to the building is a lifeline, it is desired to avoid water outage as much as possible. According to the water supply device 200 provided with the pump device 100 according to the present embodiment, tap water, which is the handling liquid, is supplied to the building by operating the pump unit 1 different from the pump unit 1 in which the abnormality has occurred. You can continue. Hereinafter, an example of this operation control operation will be described.

When an abnormality occurs in the pump units 1B and 1C other than the first stage pump unit 1A, the control unit 8 abnormally stops only the pump unit 1B (or 1C) in which the abnormality has occurred. When the abnormally stopped pump unit 1B (or 1C) is in operation, the control unit 8 refers to the abnormally stopped pump unit 1B (or 1C) while continuing the operation of the first stage pump unit 1A. Start different pump units 1C (or 1B).

If the abnormally stopped pump unit 1B (or 1C) is stopped, the pump unit 1B (or 1C) cannot be started. In this case, when the next pump unit start condition is satisfied (see Yes in step 3 of FIG. 14), the control unit 8 sets the pump unit 1C (or 1B) different from the pump unit 1B (or 1C) that is abnormally stopped. Start. Therefore, the water supply device 200 can send water having a desired flow rate to the water supply destination at a desired discharge pressure.

When the pump unit abnormally stopped is the first stage pump unit 1A, the control unit 8 causes all the pump units 1A, 1B, and 1C to be abnormally stopped. In one embodiment, when the first stage pump unit 1A is abnormally stopped, the other pump units 1B and 1C may be operated to supply water to the water supply destination. In this case, the flow rate of water that can be supplied to the water supply destination may be smaller than the desired flow rate, but it is possible to prevent the building from being cut off.

In one embodiment, the control unit 8 stores a first threshold value for emergency stopping each pump unit 1 due to overheating, and a pump output from a temperature sensor 18 attached to each pump unit 1. When the measured value of the temperature becomes equal to or higher than this first threshold value, the corresponding pump unit 1 is stopped in an emergency.

Further, the control unit 8 stores in advance a second threshold value lower than the first threshold value. The first threshold value is the temperature of the pump unit 1 in which the pump unit 1 is emergency stopped due to overheating, for example, 60 ° C. The second threshold is lower than this first threshold, for example set to 50 ° C. When the pump temperature measured by the temperature sensor 18 is higher than the second threshold value, the control unit 8 determines that a temperature abnormality has occurred in the corresponding pump unit 1, and abnormally stops only the corresponding pump unit 1. Let (temperature stop).

Further, the control unit 8 starts the pump unit 1 other than the pump unit 1 that has been abnormally stopped, and continues to send water having a desired flow rate to the water supply destination at a desired discharge pressure. As a result, water flows through the plurality of pump units 1A, 1B, and 1C, so that the temperature of the pump unit 1 abnormally stopped due to a temperature abnormality can be quickly lowered.

The control unit 8 may have a third threshold value lower than the second threshold value. The third threshold value is a temperature at which the pump unit 1 abnormally stopped due to a temperature abnormality can be restarted, and is sometimes referred to as a “return temperature”. When the temperature of the abnormally stopped pump unit 1 becomes equal to or lower than the third threshold value, the control unit 8 releases the abnormally stopped pump unit 1. As a result, all the pump units 1 can be operated.

In order to avoid water interruption to the building as much as possible, the rated capacity of the first stage pump unit 1A may be larger than the rated capacity of the other pump units 1B and 1C. Further, the limit value of the current supplied to the first stage pump unit 1A may be different from the limit value of the current supplied to the other pump units 1B and 1C. For example, the limit value of the current supplied to the first stage pump unit 1A may be set smaller than the limit value of the current supplied to the other pump units 1B and 1C. By taking such measures, the first stage pump unit 1A can be operated with a margin, and the life of the first stage pump unit 1A can be expected to be extended.

Some users of the water supply device 200 may desire to continue the operation of the water supply device 200 as much as possible. In this case, the control unit 8 may continue the operation of the first stage pump unit 1A even if the pump temperature of the first stage pump unit 1A measured by the temperature sensor 18A reaches the second threshold value. That is, the control unit 8 may continue the operation of the first stage pump unit 1A until the pump temperature of the first stage pump unit 1A reaches the first threshold value and is stopped in an emergency.

As shown in FIG. 16, the pump device 100 mounted on the water supply device 200 may further include an operation device 247 connected to the control unit 8. In the present embodiment, the operating device 247 is arranged on the control unit 8, but the operating device 247 may be arranged away from the control unit 8 as long as it is electrically connected to the control unit 8. For example, the operating device 247 is a display-operable external display connected to the control unit 8 by wireless communication such as short-range wireless communication (NFC) or BLUETOOTH (registered trademark), or wired communication such as wired network or serial communication. It may be a vessel (not shown). The operation device 247 shown in FIG. 16 includes an operation changeover switch 252 that selects test / stop / automatic operation of each pump unit 1, a lamp 253 that indicates operation / failure, and various set values necessary for the operation of the water supply device 200 ( It is provided with an operation unit 255 as an input device having an operation button 254 for inputting (for example, discharge pressure) to the control unit 8. Further, the operation device 247 includes a display device 256 including a liquid crystal display for displaying information on water supply and drive circuits 7A, 7B, 7C. The operation unit 255 and the display device 256 as an input device have an integrated configuration, but in one embodiment, the operation unit 255 and the display device 256 may be arranged apart from each other.

By operating the operation changeover switch 252, the operation state of each pump unit 1 can be switched. Specifically, when "automatic" is selected by the operation changeover switch 252 of the operation device 247, the control unit 8 supplies water by the above-mentioned automatic operation, so that the drive circuits 7A, 7B, and 7C, which are inverter devices, are the control units. The operation of each pump unit 1 is controlled at a variable speed according to the command from 8. When "stop" is selected with the operation changeover switch 252, the control unit 8 stops the operation of each pump unit 1 regardless of the state of the discharge pressure. Further, when "test" is selected by the operation changeover switch 252, the user can manually operate each pump unit 1 via the control unit 8.

Further, by operating the operation button 254 of the operation unit 255, various setting values necessary for the operation of the water supply device 200 can be input, and settings used for variable speed control of the drive circuits 7A, 7B, 7C (for example, acceleration time and acceleration time). Variable speed control parameters such as deceleration time and stall current value) and the contents displayed on the display device 256 can be changed (switched). Examples of various set values required for the operation of the water supply device 200 include set values of discharge pressure, first to third threshold values relating to the temperature of each pump unit 1, and the like. Specifically, the set value of the discharge pressure is the set pressure of the constant pressure control and / and the set pressure of the estimated end pressure constant control. The set pressure of the estimated terminal pressure constant control may be the target value of the discharge pressures of the plurality of pump units 1A, 1B, 1C at the maximum flow rate. In addition, starting conditions, next pump unit starting conditions, one after another pump unit starting conditions, one after another pump unit stopping conditions, next pump unit stopping conditions, and all stopping conditions are also included in various set values necessary for the operation of the water supply device 200. Further, the above-mentioned abnormal stop detection parameter is also included in various set values required for the operation of the water supply device 200.

FIG. 19 is a schematic view showing another example of the water supply device equipped with the pump device according to the above-described embodiment. More specifically, FIG. 19 is a schematic view showing an example of a water supply device 200 equipped with a plurality of pump devices 100 according to the above-described embodiment. Since the configuration of the present embodiment, which is not particularly described, is the same as the configuration of the water supply device 200 shown in FIG. 16, the duplicate description thereof will be omitted.

Each pump device 100 shown in FIG. 19 includes a plurality of pump units 1A, 1B, 1C having the same configuration as the pump device 100 shown in FIG. The first stage pump unit 1A of each pump device 100 is connected to a branch suction pipe 219A branched from the suction collecting pipe 219, and the pump unit 1C located at the rearmost stage is connected to the branch drain pipe 220A. The branch drainage pipe 220A joins the drainage collecting pipe 220.

Each pump device 100 includes the check valve 222 and a flow switch 224. On the other hand, each pump device 100 includes a common discharge pressure sensor 226 and a pressure tank 223. The check valve 222 and the flow switch 224 of each pump device 100 are attached to the branch suction pipe 219A, and the discharge pressure sensor 226 and the pressure tank 223 common to each pump device 100 are connected to the drainage collecting pipe 220. ing.

The water supply device 200 shown in FIG. 19 has a control unit 8 having the same configuration as the control unit 8 described with reference to FIG. 16, and the control unit 8 controls the operation of each pump device 100. do. That is, the control unit 8 shown in FIG. 19 functions as a common control unit in each pump device 100. In one embodiment, each pump device 100 may have a dedicated control unit 8. In this case, each control unit 8 is configured to be able to transmit and receive information to and from each other, and is connected by, for example, a signal line and / or a communication line.

As shown in FIG. 19, the suction collecting pipe 219 of the water supply device 200 is connected to the water receiving tank 206, and the water supply device 200 transfers the tap water stored in the water receiving tank 206 to the transfer destination (for example, the faucet of the building). Transfer. The water receiving tank 206 is connected to the water pipe 209 via the introduction pipe 210, and the water flowing through the water pipe 209 is transferred to the water receiving tank 206 through the introduction pipe 210.

A water level detector 260 for detecting the water level in the water receiving tank 206 is attached to the water receiving tank 206. The water level detector 260 shown in FIG. 19 is an electrode rod type water level detector that detects a water level using a plurality of electrode rods. The water level detector 260 is also connected to the control device 8 via a signal line. In one embodiment, the water level detector 260 may be a float switch type water level detector or an ultrasonic type water level detector.

The water supply device 200 of the present embodiment uses a plurality of pump units 1A, 1B, 1C of each pump device 100 to transfer tap water stored in the water receiving tank 206 to a transfer destination. As described above, the first-stage pump unit 1A has a suction performance capable of transferring the handling liquid to the second-stage pump unit 1B following the first-stage pump unit 1A at a desired flow rate. Therefore, even when the water supply device 200 is installed at a position higher than the liquid level of the water receiving tank 206, tap water can be transferred to the transfer destination. Further, each pump device 100 can freely adjust the pressure of the liquid to be handled by the pump units 1B and 1C after the first stage pump unit 1A. Therefore, tap water having a flow rate required at the transfer destination can be transferred to the transfer destination at a desired pressure.

Each pump device 100 is operated in the start and stop operations described with reference to FIGS. 17 and 18. Further, the control unit 8 is configured to be able to detect an abnormality generated in each pump device 100 for each pump unit 1. Although the pump unit 1 in which the abnormality is detected is abnormally stopped, tap water can be transferred to a transfer destination such as a faucet of a building by using another pump unit 1. Therefore, it is possible to prevent water outages in the building.

In this embodiment, the water supply device 200 includes a plurality of (two in FIG. 19) pump devices 100 that are operated in this way. When one pump device 100 is in operation, the other pump device 100 is in a standby state as a spare pump device. In the water supply device 200 equipped with three or more pump devices 100, it is preferable that at least one pump device 100 is in a standby state as a spare pump device. The control unit 8 controls the operation of the pump devices 100 so that the number of operations and the stop time of each of the pump devices 100 are leveled. For example, when the water supply device 200 has two pump devices 100, the control unit 8 operates the pump devices 100 alternately.

According to the water supply device 200 according to the present embodiment, the life of each pump device 100 can be expected to be extended. Further, even if one pump device 100 becomes inoperable, tap water can be transferred to the building by another pump device 100. Therefore, it is possible to prevent the water from being cut off in the building.

In one embodiment, one of the plurality of pumping devices 100, the pumping device 100, may be set as an emergency pumping device at all times in a standby state. An emergency pump device is a pump device that is operated when all pump devices other than the emergency pump device fail. In this case as well, it is possible to prevent the building from being cut off.

The above-described embodiment is described for the purpose of enabling a person having ordinary knowledge in the technical field to which the present invention belongs to carry out the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is construed in the broadest range according to the technical idea defined by the claims.

1A, 1B, 1C Pump unit 2A, 2B, 2C Pump casing 3A, 3B, 3C Motor casing 4 Suction casing 5A, 5B, 5C Permanent magnet 6A, 6B, 6C Motor stator 7A, 7B, 7C Drive circuit (inverter device)
8,8A, 8B, 8C Control unit 9,9A, 9B, 9C Power supply 10A, 10B, 10C Bearing 14A, 14B, 14C Impeller 15 Guide member 18A, 18B, 18C Temperature sensor 20A Vibration sensor 21 First stage diffuser 22A, 21B, 22C Intermediate diffuser 23A, 23B, 23C Stator core 24A, 24B, 24C Stator coil 25A, 25B, 25C Protrusions 26A, 26B, 26C Communication flow path 27A, 27B Circuit casing (inverter casing)
33A, 33B, 33C Motor chamber 37A, 37B, 37C Opening hole 40 Opening hole 50A, 50B Heat dissipation fin (heat dissipation member)
53A, 53B Opening hole 54A, 54B Opening hole 100 Pump device 200 Water supply device 224 Float switch 226 Pressure sensor 251 Current detector

Claims (22)

A pump device that transfers the handling liquid.
Equipped with multiple pump units connected continuously in series,
Each pump unit
An impeller with embedded magnets and
A motor stator arranged at a position facing the magnet and
The pump casing that houses the impeller and
A motor casing for accommodating the motor stator and a motor casing are provided.
The first-stage pump unit located at the earliest stage among the plurality of pump units is characterized by having a suction performance capable of transferring the handling liquid to a second-stage pump unit following the first-stage pump unit at a desired flow rate. Pump device. The pump device according to claim 1, wherein the impeller of at least one of the plurality of pump units is operated at a rotation speed different from the rotation speed of the impellers of the other pump units. The pump device according to claim 2, wherein the impeller of the first-stage pump unit is operated at a rotation speed lower than the rotation speed of the impeller of a pump unit other than the first-stage pump unit. The pump device according to any one of claims 1 to 3, wherein the suction diameter of the impeller of the first-stage pump unit is larger than the suction diameter of the impeller of a pump unit other than the first-stage pump unit. The pump device according to any one of claims 1 to 4, wherein the outlet width of the impeller of the first-stage pump unit is larger than the outlet width of the impeller of a pump unit other than the first-stage pump unit. The pump device according to claim 3, wherein the impellers of the plurality of pump units have the same shape. The motor casing
The motor chamber in which the motor stator is housed and
The pump device according to any one of claims 1 to 6, further comprising at least one motor chamber inlet hole for allowing the handling liquid to flow into the motor chamber. The motor casing is characterized by having at least one motor chamber outlet hole for discharging the handling liquid in the motor chamber by the handling liquid flowing into the motor chamber through the motor chamber inlet hole. The pump device according to claim 7. The first stage pump unit further includes a suction casing having a suction port.
The pump device according to claim 7, wherein the suction casing is provided with a guide member for guiding the handling liquid that has passed through the suction port so as to pass through the inlet hole of the motor chamber. The pump device according to any one of claims 1 to 9, wherein each pump unit of the plurality of pump units has an inverter device for operating the impeller at a variable speed. Each pump unit further comprises an inverter casing having an inverter chamber in which the inverter device is housed.
The pump device according to claim 10, wherein the inverter casing has at least one inverter chamber inlet hole for allowing the handling liquid to flow into the inverter chamber. The inverter casing is connected to the motor casing and is connected to the motor casing.
The pump device according to claim 11, wherein the inverter casing has at least one communication hole for allowing the handling liquid in the inverter chamber to flow into the motor casing. Each pump unit of the plurality of pump units
An inverter device for operating the impeller at variable speed,
Further provided with an inverter casing having an inverter chamber in which the inverter device is housed,
The inverter casing is connected to the motor casing and is connected to the motor casing.
The inverter casing
At least one communication hole for allowing the handling liquid in the motor chamber to flow into the inverter chamber,
7. A claim 7 is characterized in that it has at least one inverter chamber outlet hole for discharging the handling liquid in the inverter chamber by the handling liquid flowing into the inverter chamber through the communication hole. The pump device described in. The pump device according to any one of claims 1 to 13, wherein the handling liquid has an insulating property. A control unit that controls the operation of the plurality of pump units is further provided.
The control unit is characterized in that it performs automatic operation control for first starting the first-stage pump unit when a predetermined start condition is satisfied and finally stopping the first-stage pump unit when a predetermined stop condition is satisfied. The pump device according to 1. A pressure sensor for measuring the discharge pressure of the plurality of pump units is further provided.
The pump device according to claim 15, wherein the control unit determines that the starting condition is satisfied when the discharge pressure drops to a predetermined starting pressure. Further provided with a flow rate detector for detecting a small amount of water state in which the flow rate of the handling liquid discharged from the plurality of pump units is equal to or less than a predetermined small amount of water.
The pump device according to claim 15 or 16, wherein the control unit determines that the stop condition is satisfied when the flow rate detector detects a small amount of water state. The pump device according to claim 15, wherein the control unit starts a second pump unit different from the first-stage pump unit when the next pump unit start condition is satisfied during the operation of the first-stage pump unit. .. A pressure sensor for measuring the discharge pressure of the plurality of pump units is further provided.
18. The control unit determines that the next pump unit start condition is satisfied when the discharge pressure becomes equal to or lower than a predetermined threshold value during the operation of the first stage pump unit. The pump device described. The control unit is characterized in that, when the next pump unit stop condition is satisfied during the operation of the first stage pump unit and the second stage pump unit, the second pump unit is stopped before the first stage pump unit. The pump device according to claim 18 or 19. 20. The control unit determines that the next pump unit stop condition is satisfied when the discharge pressure exceeds a predetermined threshold value during the operation of the first stage pump unit. The pump device described. A water supply device equipped with at least one pump device.
The water supply device according to any one of claims 1 to 21, wherein the pump device is the pump device.

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