JP7448412B2 - pump equipment - Google Patents

Description

The present invention relates to a pump device, and particularly to a pump device disposed in a water supply device.

BACKGROUND Water supply devices are widely used as devices for supplying water to buildings such as office buildings and condominiums (for example, see Patent Document 1). A water supply device generally includes at least a pump device for pumping water and a control unit that controls the operation of the pump device. The water supply device is connected, for example, directly to a water main or via a water tank, and supplies water flowing through the water main to a water supply destination such as a water supply device (for example, a faucet) in a building.

Unexamined Japanese Patent Publication No. 2017-137800

Since the water supply device is a lifeline facility that supplies water to the water supply destination, it is preferable that the water supply device be operated as continuously as possible so as not to cause a water outage to the water supply destination. However, if the pump device stops due to an abnormality occurring in the pump device, the water supply device will no longer be able to supply water to the water supply destination.

Therefore, an object of the present invention is to provide a pump device that can continue to supply handling liquid such as water as much as possible.

In one embodiment, there is provided a pump device that transfers a liquid to be handled, and the pump device includes a plurality of pump units connected in series and a control section that controls operations of the plurality of pump units, and each pump unit has a plurality of pump units. , an impeller in which a magnet is embedded, a motor stator disposed at a position facing the magnet, a pump casing accommodating the impeller, and a motor casing accommodating the motor stator. There is provided a pump device, wherein the control section is configured to be able to detect an abnormality occurring in each pump unit for each pump unit.

In one aspect, the control unit abnormally stops a pump unit in which an abnormality has occurred among the plurality of pump units.
In one aspect, when the pump unit in which the abnormality has occurred is a first-stage pump unit located at the forefront of the plurality of pump units, the control unit abnormally stops all pump units of the plurality of pump units. .
In one aspect, when an abnormality occurs in a pump unit other than the first-stage pump unit among the plurality of pump units, the control unit abnormally stops only the pump unit in which the abnormality has occurred.

In one aspect, the pump device further includes a temperature sensor that measures the temperature of each pump unit, and the detectable abnormality for each pump unit is such that the measured value of the temperature sensor is a predetermined first threshold value. This is a temperature anomaly where the temperature is higher than the normal temperature.
In one aspect, the control unit is configured to control, when a measured value of the temperature sensor of a second pump unit different from the first stage pump unit reaches a second threshold value set lower than the first threshold value. , the second pump unit is abnormally stopped, and at least the first stage pump unit is made operable.
In one aspect, after the second pump unit is abnormally stopped, the measured value of the temperature sensor of the second pump unit decreases to a third threshold value that is set lower than the second threshold value. At this time, the control section cancels the abnormal stop of the second pump unit.

In one aspect, the control section continues to operate the first-stage pump unit even if the measured value of the temperature sensor of the first-stage pump unit reaches the second threshold.
In one aspect, the pump device further includes current detection means for measuring a current value supplied to each pump unit, and the control unit monitors the measured value of the current detection means, and the control unit monitors the measured value of the current detection means, and The abnormality that can be detected for each unit is an overcurrent abnormality in which the measured value of the current detection means exceeds a predetermined limit value.
In one aspect, the limit value of the first-stage pump unit is different from the limit value of pump units other than the first-stage pump unit.

In one aspect, the rated capacity of the first stage pump unit is larger than the rated capacity of pump units other than the first stage pump unit.
In one aspect, the first stage pump unit has higher suction performance than pump units other than the first stage pump unit.
In one aspect, each pump unit further includes an inverter device that controls the impeller at variable speed, and the operating speed of the first-stage pump unit is slower than the operating speed of pump units other than the first-stage pump unit.

In one aspect, the pump device is configured to detect a small water flow state in which the flow rate of the handled liquid discharged from the final stage pump unit located at the rearmost stage of the plurality of pump units is less than or equal to a predetermined small water flow rate. and a pressure sensor that measures the discharge side pressure of the final stage pump unit, and the control unit controls the discharge side pressure of the plurality of pump units when the discharge side pressure decreases to a predetermined starting pressure or less. At least one of the pump units is activated, and when the low water flow state is detected, automatic operation control is performed to stop the activated pump unit with a low water flow, and among the plurality of pump units, the pump in which the abnormality has occurred is controlled. The automatic operation control is performed except for the unit.

According to the present invention, according to the present invention, abnormalities that occur in each pump unit can be determined for each pump unit. Therefore, by operating a pump unit different from the pump unit in which the abnormality has occurred, it is possible to continue supplying the handled liquid.

FIG. 1(a) is a schematic diagram showing an example of the arrangement of the pump device according to one 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 diagram. FIG. 2 is a schematic sectional view of the pump device shown in FIG. 1(a). FIG. 3(a) is a schematic diagram showing an example of a drive circuit and a control section connected to a plurality of pump units, and FIG. 3(b) is a schematic diagram showing an example of a drive circuit and a control section connected to a plurality of pump units. It is a schematic diagram which shows another example, and FIG.3(c) is a schematic diagram which shows still another example of the drive circuit and control part connected to several pump units. FIG. 4 is a schematic cross-sectional view showing an enlarged impeller of the first stage pump unit. FIG. 5(a) 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 rotational 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 rotational speeds. FIG. 6 is a schematic cross-sectional view of a pump device according to another embodiment. FIG. 7 is a schematic cross-sectional view of a pump device according to yet another embodiment. FIG. 8 is a schematic diagram showing a plurality of openings formed in the bottom wall of the suction casing. FIG. 9 is a schematic cross-sectional view for explaining a modification of the pump device shown in FIG. 7. FIG. 10 is a schematic cross-sectional view of a pump device according to yet another embodiment. FIG. 11 is a schematic cross-sectional view of a flow path of an inverter casing provided with radiation fins. FIG. 12 is a schematic cross-sectional view of a pump device according to yet another embodiment. FIG. 13 is a schematic cross-sectional view for explaining a modification of the pump device shown in FIG. 12. FIG. 14 is a schematic cross-sectional view for explaining a modification of the pump device shown in FIG. 13. FIG. 15 is a schematic cross-sectional view for explaining another modification of the pump device shown in FIG. 13. FIG. 16 is a schematic diagram showing an example of a water supply device equipped with the pump device according to the embodiment described above. FIG. 17 is a flowchart for explaining an example of the starting operation of the pump device installed in the water supply device shown in FIG. 16. FIG. 18 is a flowchart for explaining an example of the stopping operation of the pump device installed in the water supply device shown in FIG. 16. FIG. 19 is a schematic diagram showing another example of a water supply device equipped with the pump device according to the embodiment described above.

Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same or corresponding components are given the same reference numerals and redundant explanation will be omitted. In addition, in the following drawings and descriptions, the subscripts (A, B, C), which are uppercase letters, attached to the end of each symbol indicate which pump unit of the pump device the component with the subscript is attached to. This is an inclusive symbol that indicates whether the item belongs to the item. For example, the suffix "A" is attached to the component of the first-stage pump unit located at the forefront of multiple pump units, and the suffix "B" is attached to the component of the second-stage pump unit that follows the first-stage pump unit. will be attached. Furthermore, the subscripts "A, B, C" may be omitted when there is no particular need to distinguish them, and when components common to a plurality of pump units are representatively shown.

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

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

Note that the arrangement position of the pump device 100 with respect to the liquid level of the handled liquid in the suction tank 110 is arbitrary, and is not limited to the example 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. Furthermore, the plurality of pump units 1 of the pump device 100 may be arranged diagonally with respect to the horizontal or vertical direction. Furthermore, 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 includes 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) that can prevent leakage of handled liquid. In the following, the configuration of the first stage pump unit 1A located at the forefront of the plurality of pump units 1A, 1B, and 1C will be explained, but the pump units 1A, 1B, and 1C have the same configuration unless otherwise explained. Therefore, the repeated explanation 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 magnetic force acting on the permanent magnet 5A, a pump casing 2A that houses the impeller 14A, and a motor stator. The motor casing 3A has a motor chamber 33A that accommodates the impeller 14A, and a bearing 10A that supports the radial load and thrust load of the impeller 14A.

An O-ring 9A serving 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 small 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, it is preferable that the size of this gap is 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 the single bearing 10A. In this embodiment, the bearing 10A is a sliding bearing (dynamic pressure bearing) that utilizes the dynamic pressure of the handled liquid. In one embodiment, the bearing 10A may be a sliding bearing that does not utilize the dynamic pressure of the handling liquid.

The bearing 10A shown in FIG. 2 is constructed from a combination of a rotating bearing element 11A and a stationary bearing element 12A that are loosely engaged with each other. The rotating 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. This 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 an annular shape, and the inner circumferential surface of the rotating side bearing element 11A faces the radial surface 12Aa of the stationary side bearing element 12A, and the side surface of the rotating side bearing element 11A faces the stationary side bearing element 12A. It faces the thrust surface 12Ab of. A small gap is formed between the inner circumferential surface of the rotating bearing element 11A and the radial surface 12Aa, and between the side surface of the rotating bearing element 11A and the thrust surface 12Ab. Furthermore, spiral grooves (not shown) for generating dynamic pressure are formed on the inner circumferential surface and 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 small gap between the impeller 14A and the motor casing 3A. When the rotating side bearing element 11A rotates together with the impeller 14A, dynamic pressure of the handling liquid is generated between the rotating side bearing element 11A and the stationary side bearing element 12A, and as a result, the impeller 14A is supported by the bearing 10A in a non-contact manner. be done. Since the fixed side bearing element 12A supports the rotating side bearing element 11A by the orthogonal radial surface 12Aa and thrust surface 12Ab, the tilting of the impeller 14A is regulated by the bearing 10A. The bearing 10A (that is, the rotating bearing element 11A and the stationary bearing element 12A) is made of a material with excellent wear resistance, such as ceramic or carbon.

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

Note that, although one permanent magnet 5A having an annular shape is embedded in the impeller 14A shown in FIG. 2, the present 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, the plurality of permanent magnets 5A embedded in the impeller 14A are arranged in a ring shape, and each permanent magnet 5A has, for example, a fan shape.

The impeller 14A is formed from a non-magnetic material. Furthermore, impeller 14A is preferably formed from a material that is slippery and hard 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 from a magnetic material (for example, metal) or a non-magnetic material. If pump casing 2A is formed from a non-magnetic material, pump casing 2A may be formed from the same material as impeller 14A.

In this embodiment, the motor casing 3A has an annular motor chamber 33A. The motor stator 6A is housed in the motor chamber 33A. The motor stator 6A includes a stator core 23A having a plurality of teeth, and stator coils 24A wound around each of these teeth. The teeth and stator coil 24A are arranged annularly, and the impeller 14A and 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 electrical insulation of the motor stator 6A and preventing the generation of eddy currents, the motor casing 3A is preferably formed from a non-metallic material. Examples of non-metallic materials forming the motor casing 3A include resins such as PPS (polyphenylene sulfide), PFA (tetrafluoroethylene perfluoroalkyl vinyl ether copolymer), and PEEK (polyether ether ketone). . The motor casing 3A may be formed from the same resin material as the impeller 14A. The resin motor casing 3A has the advantage that even if the stator coil 24A comes into contact with the motor casing 3A, the stator coil 24A remains electrically insulated 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 source. 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, thereby causing the impeller 14A to rotate.

The first-stage pump unit 1A located at the forefront of the plurality of pump units 1A, 1B, and 1C has a suction casing 4 having a suction port 4a, unlike the other pump units 1B and 1C. 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 body 4b that is connected to the suction port 4a, and the suction port 4a is connected to an inlet line for handling liquid (not shown). The inlet line is, for example, a line that extends from a transfer source such as a suction tank to the pump device 100. In this embodiment, the suction port 4a is arranged at the center of the suction casing 4. Specifically, the center of the suction port 4a is on the central axis of the casing body 4b of the suction casing 4. The suction casing 4 may be formed from the same material as the impeller 14A. Furthermore, the suction port 4a may be formed integrally with the casing body 4b.

When the impeller 14A rotates, the treated liquid is introduced from the suction port 4a of the suction casing 4 to the liquid inlet of the impeller 14A. The handled liquid is pressurized by the rotation of the impeller 14A, and is 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 pressurized handling liquid. Since the bearing 10A is disposed on the suction side of the impeller 14A, it supports the thrust load of the impeller 14A from the suction side. According to the configuration according to the present embodiment, the radial load and thrust load of the impeller 14A can be supported by one bearing 10A without contact, thereby realizing a compact pump unit that does not generate particles. Can be done.

Since the other pump units 1B, 1C have similar configurations, each pump unit 1A, 1B, 1C can be configured compactly. Therefore, by connecting these pump units 1A, 1B, and 1C in series, it is possible to downsize the pump device 100.

A discharge port 16 is formed in the pump casing 2C of the third stage pump unit 1C which is arranged at the rearmost stage among the plurality of pump units 1A, 1B, and 1C. This discharge port 16 is connected to a handling liquid outlet line (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 this 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 pump casing 2A of the first stage pump unit 1A, the motor casing 3B and pump casing 2B of the second stage pump unit 1B, and the motor casing 3C and pump casing 2C of the third stage pump unit 1C, They are arranged in this order, and in this state they are connected together by a plurality of connection bolts (not shown).

In this embodiment, the first stage pump unit 1A has suction performance that allows the handling liquid to be transferred at a desired flow rate to the second stage pump unit 1B following the first stage pump unit 1A. For example, the first stage pump unit 1A has a lift H (see FIGS. 1(a) and 1(b)) that can transfer the handled liquid stored in the suction tank 110 at a desired flow rate to the second stage pump unit 1B. .

The handled liquid sucked into the first-stage pump unit 1A is transferred to the second-stage pump unit 1B, and is pressurized by the second-stage pump unit 1B. The handled liquid whose pressure has been increased by the second stage pump unit 1B is transferred to the third stage pump unit 1C, and the pressure of the handled liquid is further increased by the third stage pump unit 1C. Thereafter, the handled liquid is discharged from the discharge port 16 formed in the pump casing 2C of the third stage pump unit 1C to an outlet line (not shown).

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

As described above, the three lead wires 17A are connected to the stator coil 24A of the first stage pump unit 1A, and the ends of the lead wires 17A are 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 then 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 a control section 8A that controls the operation of the drive circuit 7A and a power source 9A. Similarly, the drive circuit 7B is connected to a control section 8B that controls the operation of the drive circuit 7B and a power source 9B, and the drive circuit 7C is connected to a control section 8C that controls the operation of the drive circuit 7C and a power source 9C. connected to. The drive circuits 7A, 7B, 7C are, for example, inverter devices, and the control units 8A, 8B, 8C control the power supply 9A by using power elements (for example, switching elements such as IGBT elements) arranged in the inverter devices. , 9B, 9C to the stator coils 24A, 24B, 24C, respectively.

In the example shown in FIG. 3(b), drive circuits 7A, 7B, and 7C are connected to a common power source 9. In the example shown in FIG. 3C, the operations of the drive circuits 7A, 7B, and 7C are further controlled by a common control section 8.

In any of the examples shown in FIGS. 3(a) to 3(c), the control unit 8A, 8B, 8C or the control unit 8 controls the rotational speed of the impeller 14A, 14B, 14C to the drive circuit 7A, 7B, 7C. each can be adjusted arbitrarily and independently via the . That is, the control units 8A, 8B, 8C or the control unit 8 can independently control the operating speed of each pump unit 1A, 1B, 1C via each drive circuit 7A, 7B, 7C.

According to such a configuration, the first stage pump unit 1A of the pump device 100 transfers the handled liquid at a desired flow rate from the transfer source (for example, the suction tank 110 shown in FIGS. 1(a) and 1(b)) to the second stage. can be transferred to the second pump unit 1B. As described above, the control units 8A, 8B, 8C or the control unit 8 can independently control the operating speed of each pump unit 1A, 1B, 1C. 1C allows the pressure of the liquid to be adjusted freely. As a result, it is possible to provide a small, high-head pump device 100 with improved suction performance.

As described above, the first stage pump unit 1A has suction performance capable of transferring the handled liquid to the second stage pump unit 1B at a desired flow rate. In this embodiment, the controllers 8A, 8B, 8C or the controller 8 operate the first stage pump unit 1A at a lower speed than the operating speeds of the other pump units 1B, 1C. Generally, by lowering the operating speed of the pump (ie, the rotational speed of the impeller), the suction performance of the pump can be increased more than when operating at high speed. However, the head of the pump will be lower than when operating at high speed.

In this embodiment, the first stage pump unit 1A transfers the handled liquid to the second stage pump unit 1B at a desired flow rate, and the pressure of the handled 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 made low, the pump device 100 can ensure the desired head. In this case, since the impellers 14A, 14B, and 14C having the same shape can be used, the manufacturing cost and management cost of the pump device 100 can be reduced. In addition, in order to ensure the desired head, it is of course possible to operate the pump units 1B and 1C other than the first stage pump unit 1A at different operating speeds.

In order to ensure the suction performance required of 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. It's okay.

FIG. 4 is a schematic cross-sectional view showing an enlarged view of the impeller 14A of the first stage pump unit 1A. In order to ensure the suction performance required of the first stage pump unit 1A, the suction aperture d1 of the impeller 14A of the first stage pump unit 1A is made larger than the suction apertures of the impellers 14B and 14C of the other pump units 1B and 1C. It's okay. In one embodiment, the suction diameters of the impellers 14B and 14C of the other pump units 1B and 1C may be made different from each other. Generally, the suction performance of the pump can be increased by increasing the suction diameter of the impeller of the pump. Note that the impeller 14A having a suction aperture d1 larger than the suction apertures 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 or in addition to making the suction aperture d1 of the impeller 14A larger than the suction apertures of the other impellers 14B and 14C, the outlet width b of the impeller 14A is made larger than the outlet width of the other impellers 14B and 14C. It 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 made different from each other. Generally, the suction performance of a pump can be increased by increasing the outlet width of the impeller of the pump. Note that the impeller 14A having a suction aperture d1 and/or an outlet width b larger than the suction aperture and/or outlet width b of the impellers 14B and 14C of the other pump units 1B and 1C is operated at a lower speed than the impellers 14B and 14C. You can also rotate it with

Furthermore, according to the pump device 100 according to the present embodiment, vibration and noise generated from the pump device 100 can be reduced. FIG. 5(a) 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 rotational 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 rotational speeds. In FIGS. 5(a) and 5(b), the vertical axis represents the sound pressure level of the noise, and the horizontal axis represents the frequency of the noise.

As shown in FIG. 5(a), when a plurality of pump units 1A, 1B, 1C each equipped with impellers 14A, 14B, 14C having the same configuration are operated at the same rotational speed, each pump unit 1A, 1B , 1C may be superimposed and loud noise may be generated from the pump device 100. There is a possibility that the vibrations generated in each pump unit 1A, 1B, and 1C may also become large due to being superimposed (for example, resonating). Furthermore, there is a possibility that the frequency of the pulsation of the discharge pressure generated in each of the pump units 1A, 1B, and 1C becomes the same, and in this case, the amplitude of the vibration generated in the pump device 100 becomes large.

In this embodiment, the controllers 8A, 8B, 8C or the controller 8 can independently control the operating speed of each pump unit 1A, 1B, 1C. Therefore, the impeller 14 of at least one pump unit 1 of the plurality of pump units 1A, 1B, 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. Note that, as shown in FIG. 5(b), the vibrations and noise generated from the pump device 100 can be reduced most by making the operating speeds of the pump units 1A, 1B, and 1C different. Furthermore, since it is possible to avoid all the frequencies of the pulsations of the discharge pressure occurring in each pump unit 1A, 1B, and 1C being the same, the amplitude of vibrations occurring in the pump device 100 can also be reduced.

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

FIG. 6 is a schematic cross-sectional view of a 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 in the motor stators 6A, 6B, and 6C leads to deterioration and breakage of the motor stators 6A, 6B, and 6C. Therefore, the pump device 100 shown in FIG. 6 is provided with a configuration that efficiently cools the motor stators 6A, 6B, and 6C. Note that configurations that are not particularly explained in this embodiment are the same as those in the above-described embodiment, and therefore, redundant explanation 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 handled liquid sucked from the suction port 4a and guides the handled liquid so that it passes through the first stage diffuser 21 (described later). It 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 (the lower surface in FIG. 6) of the guide member 15 toward the outside in the radial direction of the suction casing 4, and flows toward the radially outer side of the suction casing 4. collides with the inner surface of the side wall. Then, the handled liquid flows around the other surface (the upper surface in FIG. 6) of the guide member 15 and flows toward the inside of the suction casing 4 in the radial direction. That is, the guide member 15 forms a suction flow path 4c for the handled liquid that radially spreads outward in the radial direction of the suction casing 4 and then converges in the radial direction of the suction casing 4. This suction passage 4c is formed in the casing body 4b, extends from the suction port 4a, and is connected to a passage 3Aa formed in the motor casing 3A.

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

Liquid flow paths 3Aa and 10Aa are formed in the center of the motor casing 3A and bearing 10A of the first stage pump unit 1A, respectively. These liquid channels 3Aa and 10Aa are connected in a line. The handling liquid that is sucked in from the suction port 4a and flows through the suction passage 4c of the suction casing 4 flows linearly through the passage 3Aa of the motor casing 3A and the passage 10Aa of the bearing 10A to the liquid inlet of the impeller 14A. It gets sucked in. In this way, the flow paths 4c, 3Aa, and 10Aa constitute 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 passage 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 channel 26A. An intermediate diffuser 22A is fixed to the wall of the communication channel 26A. More specifically, the intermediate diffuser 22A is fixed to the inner surface of the bottom wall of the pump casing 2A, which forms the wall surface of the communication channel 26A. The intermediate diffuser 22A guides the treated liquid discharged from the impeller 14A 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 bearing 10B of the second stage pump unit 1B, respectively, and the liquid flow paths 3Ba and 10Ba are also connected in a line. 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 channel 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 channel 26B. An intermediate diffuser 22B is fixed to the wall surface of the communication channel 26B. More specifically, the intermediate diffuser 22B is fixed to the inner surface of the bottom wall of the pump casing 2B, which forms the wall surface of the communication channel 26B. The intermediate diffuser 22B guides the treated liquid discharged from the impeller 14B to a 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 channel 26B of the second stage pump unit 1B flows through the liquid channels 3Ca and 10Ca formed in the center of the motor casing 3C and the bearing 10C. and is sucked into the liquid inlet of the impeller 14C. The handled liquid discharged from the impeller 14C flows through a communication channel 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, an intermediate diffuser 22C is disposed in the communication channel 26C, but this intermediate diffuser 22C may be omitted.

The motor stator 6A of the first stage pump unit 1A is in contact with the surface opposite to the wall surface to which the first stage diffuser 21 is fixed. More specifically, the motor stator 6A has an annular projection 25A, and the tip of the projection 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. are doing. Heat generated by the motor stator 6A is transmitted from the protrusion 25A to the first stage diffuser 21 via the casing body 4b. Since the first stage diffuser 21 is in contact with the handled liquid flowing through the suction channel 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 handled liquid. Ru. 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 to which the intermediate diffuser 22A is fixed, and the motor stator 6C of the third-stage pump unit 1C is in contact with the surface opposite to the wall surface to which the intermediate diffuser 22A is fixed. It is in contact with the surface opposite to the wall surface to which the diffuser 22B is fixed. More specifically, the tip of the annular projection 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 The tip of the annular projection 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 this configuration, the heat generated in the motor stator 6B is transmitted 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 channel 26A. Similarly, the heat generated by the motor stator 6C is transmitted from the protrusion 25C to the intermediate diffuser 22B via the pump casing 2B, and is dissipated from the intermediate diffuser 22B to the handled liquid flowing through the communication channel 26B. As a result, motor stators 6B and 6C can be efficiently cooled.

In this way, the first stage diffuser 21 and the intermediate diffusers 22A, 22B also function as heat radiating members for transmitting and dissipating the heat generated in the motor stators 6A, 6B, 6C to the treated liquid. As a result, a cooling device (for example, a cooling fin or a cooling fan) required in a conventional motor pump is not required, so that it is possible to suppress an increase in the size of the pump device 100 and increase in manufacturing cost. Furthermore, 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 first stage diffuser 21 and the intermediate diffusers 22A, 22B may be made of any material. However, the first stage diffuser 21 and the intermediate diffusers 22A, 22B are preferably formed from a material having high thermal conductivity in order to efficiently dissipate heat to the liquid to be handled. For example, the first stage diffuser 21 and the intermediate diffusers 22A, 22B are made of metal such as stainless steel. In one embodiment, the first stage diffuser 21 and the intermediate diffusers 22A, 22B may be formed from resin.

FIG. 7 is a schematic cross-sectional view of a pump device according to yet another embodiment. The pump device 100 shown in FIG. 7 also has a configuration that efficiently cools the motor stators 6A, 6B, and 6C. Note that configurations that are not particularly explained in this embodiment are the same as those in the above-described embodiment, and therefore, redundant explanation will be omitted.

Pump units 1A, 1B, and 1C of the pump device 100 shown in FIG. 7 each have at least one motor chamber inlet for flowing the handled liquid into the motor chambers 33A, 33B, and 33C instead of the diffusers 21, 22A, and 22B. It has holes. In this embodiment, since the handling liquid flows into the motor chambers 33A, 33B, and 33C, the handling liquid has insulation properties so that the stator coils 24A, 24B, and 24C of the motor stators 6A, 6B, and 6C do not short-circuit. (e.g., a fluorine-based insulating liquid).

In one embodiment, water-resistant insulated wires may be used as the windings of the stator coils 24A, 24B, and 24C. In this case, even if a conductive handling liquid (for example, water) flows into the motor chambers 33A, 33B, 33C, the stator coils 24A, 24B, 24C will not be short-circuited. Water-resistant insulated wire is a general term for wires whose windings themselves are liquid-proof (waterproof). A water-resistant insulated wire includes, 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 resin that has excellent water-resistant insulation performance. Such a resin is, for example, a polyolefin resin (eg, polyethylene, crosslinked polyethylene, polypropylene, etc.).

In one embodiment, the entire winding of each stator coil 24A, 24B, 24C may be molded with an insulating resin. Even with such a configuration, the stator coils 24A, 24B, 24C will not be short-circuited due to the conductive handling liquid that has flowed into the motor chambers 33A, 33B, 33C. Furthermore, in this embodiment, insulated covered electric wires, which are cheaper than water-resistant insulated electric wires, can be used as the windings of the stator coils 24A, 24B, and 24C.

An annular opening hole 37A is formed in the first stage pump unit 1A of the pump device 100 shown in FIG. 7 for allowing the handling liquid to flow into the motor chamber 33A. The motor chamber 33A of the motor casing 3A communicates with the suction passage 4c formed in the suction casing 4 through the opening hole 37A. Therefore, a part of the handling liquid flowing through the suction channel 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 entrance hole through which the handling liquid sucked from the suction port 4a flows into the motor chamber 33A. The motor stator 6A is immersed in the handling liquid that has flowed into the motor chamber 33A from the suction channel 4c through the opening hole 37A.

The heat generated in the motor stator 6A is transmitted to the handling liquid filling the motor chamber 33A, increasing the temperature of the handling liquid. However, during operation of the pump device 100, the handled liquid in the motor chamber 33A always directly exchanges heat with the lower temperature handled liquid flowing through the suction passage 4c of the suction casing 4 (see the black arrow in FIG. 7). ), thereby cooling 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 handled liquid to flow into the motor chamber 33B. communicates with the communication channel 26A. The third stage pump unit 1C is formed with an annular opening hole (motor chamber inlet hole) 37C for allowing the handled liquid to flow into the motor chamber 33C. It communicates with the 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 motor in the motor chambers 33B and 33C 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. Stators 6B and 6C are immersed in the handling liquid. During operation of the pump device 100, the handling liquid in the motor chambers 33B, 33C always directly exchanges heat with the lower temperature handling liquid flowing through the communication channels 26A, 26B, so that the motor stators 6B, 6C are cooled. be done.

In this way, in this embodiment, the motor stators 6A, 6B, 6C can be efficiently operated with a simple configuration in which the opening holes (motor chamber inlet holes) 37A, 37B, 37C are provided in each pump unit 1A, 1B, 1C. can be cooled down. As a result, a cooling device (for example, a cooling fin or a cooling fan) required in a conventional motor pump is not required, so that it is possible to suppress an increase in the size of the pump device 100 and increase in manufacturing cost. Furthermore, 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 functioning as the motor chamber entrance hole is one hole having an annular shape, and 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 entrance holes may be provided in the bottom wall of the casing body 4b of the suction casing 4. When a plurality of opening holes 37A are provided in the bottom wall of the casing body 4b, the number, position, cross-sectional shape, and size (for example, diameter) of the opening holes 37A are arbitrary; It is preferable to arrange them at equal intervals along the circumferential direction. Furthermore, one or more opening holes 37A functioning as motor chamber inlet holes may be communicated with the liquid flow path 3Aa of the motor casing 3A.

Similarly, a plurality of opening holes 37B functioning as motor chamber inlet holes and a plurality of opening holes 37C functioning as motor chamber inlet holes are connected to 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. Although the number, position, cross-sectional shape, and size (e.g., diameter) of the opening holes 37B are arbitrary, it is preferable that the plurality of opening holes 37B are arranged at equal intervals along the circumferential direction of the pump casing 2A. . Similarly, the number, position, cross-sectional shape, and size (for example, 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. Furthermore, one or more opening holes 37B functioning as a motor chamber inlet hole may be communicated with the liquid flow path 3Ba of the motor casing 3B, and one or more opening holes 37C functioning as a motor chamber inlet hole may be communicated with the liquid flow path 3Ba of the motor casing 3B. , it may be communicated with the liquid flow path 3Ca of the motor casing 3C.

In this embodiment, the handling liquid that has passed through the suction port 4a is actively guided by the guide member 15 described above so that it passes through the opening hole (motor chamber entrance hole) 37A. Therefore, the guide member 15 always creates a flow of low-temperature handling liquid above the opening hole 37A, thereby efficiently cooling the motor stator 6A.

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

As shown in FIG. 9, the motor casing 3A includes an inner cylinder 30A, an outer cylinder 31A disposed radially outward of 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-described flow path 3Aa is formed in the center thereof. The outer cylinder 31A also has a substantially cylindrical shape, and the partition wall 32A has an annular shape. This partition 32A is located between the impeller 14A and the motor stator 6A, and the rotating magnetic field generated by the motor stator 6A passes through the partition 32A and reaches the permanent magnet 5A of the impeller 14A.

As shown in FIG. 9, the motor casing 3A differs 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 aperture 40A (and the apertures 40B and 40C shown in FIG. 9) are indicated by dotted lines. The motor chamber 33A communicates with the housing space of the impeller 14A formed in the pump casing 2A through the opening hole 40A formed in the partition wall 32A.

The pressure of the handled liquid discharged from the impeller 14A is higher than the pressure of the handled liquid before being sucked into the impeller 14A (that is, the handled liquid flowing through the channels 4c, 3Aa, and 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 this embodiment, the opening hole 40A formed in the partition wall 32 serves as a motor chamber 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. Functions as an entrance hole.

In this embodiment, the handling liquid that has filled the motor chamber 33A flows through the opening hole (motor chamber inlet hole) 40A into the motor chamber 33A, and the handling liquid flows into the suction casing 4 through the opening hole 37A. It is pushed out to path 4c. That is, the above-mentioned opening hole 37A functions as a motor chamber outlet hole for the handling liquid that flows into the motor chamber 33 from the opening hole 40A and is discharged into the suction channel 4c. According to such a configuration, while the impeller 14A is rotating, that is, while the pump device 100 is operating, the handled liquid in the motor chamber 33A is always mixed with the low-temperature handled 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 that the opening holes 40A are arranged at equal intervals along the circumferential direction of the partition wall 32A. In one embodiment, the number of apertures 40A matches the number of stator coils 24A, with one aperture 40A being assigned to each stator coil 24A.

FIG. 10 is a schematic cross-sectional view of a pump device according to yet another embodiment. A pump device 100 shown in FIG. 10 includes a first stage pump unit 1A and a second stage pump unit 1B following the first stage pump unit 1A. In this embodiment, the second stage pump unit 1B is the pump unit located at the rearmost stage among the plurality of pump units 1A and 1B. Although not shown, the pump device 100 may include a further pump unit 1 following the second stage pump unit 1B.

The pump device 100 shown in FIG. 10 differs from the pump device 100 shown in FIG. 7 in that drive circuits 7A and 7B are built into pump units 1A and 1B, respectively. By incorporating the drive circuits 7A, 7B into the pump device 100, there is no need to separately prepare a box body for accommodating the drive circuits 7A, 7B. Furthermore, maintenance of the pump device 100 becomes easier.

The drive circuit 7A is housed in a circuit casing 27A, and the drive circuit 7B is housed in a circuit casing 27B. Since the circuit casing 7B has the same configuration as the circuit casing 7A described below, the redundant description thereof 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 handling liquid is formed in the center thereof. The outer cylinder 27Ab also has a substantially cylindrical shape, and the bottom wall 27Ac has an annular shape. The drive circuit 7A is housed in a drive circuit chamber 27Ae surrounded by an inner tube 27Aa, an outer tube 27Ab, and a bottom wall 27Ac. In this embodiment, the drive circuit 7A is an inverter device and has a ring shape. Hereinafter, the drive circuit 7A may be referred to as the "inverter device 7A," the circuit casing 27A may be referred to as the "inverter casing 27A," and the drive circuit chamber 27Ae may be referred to as the "inverter chamber 27Ae." Similarly, the drive circuit 7B may be referred to as the "inverter device 7B," the circuit casing 27B may be referred to as the "inverter casing 27B," and the drive circuit chamber 27Be may be referred to as the "inverter chamber 27Be."

The inverter casing 27A is sandwiched between the suction casing 4 and the motor casing 3A, and the above-described suction passage 4c is connected to a passage 27Ad formed in the inverter casing 27A. The flow path 27Ad is further connected in a line to a flow path 3Aa formed in the motor casing 3A and a flow path 10Aa formed in the bearing 10A. The handling liquid that is sucked in from the suction port 4a and flows through the suction passage 4c of the suction casing 4 flows in a straight line through the passage 27Ad of the inverter casing 27A, the passage 3Aa of the motor casing 3A, and the passage 10Aa of the bearing 10A. The liquid 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 uses the power element 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 source of the inverter device 7A is the power element. In this embodiment, the power elements that are the main heat generating sources of the inverter device 7A are integrated into the power element module 29A.

As shown in FIG. 10, the inverter device 7A is in contact with the surface opposite to the wall surface to which the above-described 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 body 4b of the suction casing 4 to which the first stage diffuser 21 is fixed. Heat generated in the inverter device 7A, particularly the power element module 29A, is transmitted to the first stage diffuser 21 via the casing body 4b. Since the first stage diffuser 21 is in contact with the handled liquid flowing through the suction channel 4c, the heat transferred from the inverter device 7A to the first stage diffuser 21 via the casing body 4b is efficiently dissipated to the handled 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. Heat generated by the motor stator 6A is transmitted to the inverter casing 27A from the protrusion 25A. 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 to 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 this configuration, the heat generated in the inverter device 7B, particularly the power element module 29B, is transmitted 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 channel 26A. Ru. As a result, the inverter device 7B can be efficiently cooled.

Furthermore, 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 diffused into the handling liquid flowing through the flow path 27Bd. As a result, the motor stator 6B can be efficiently cooled.

In this embodiment, the first stage diffuser 21 and the intermediate diffuser 22A also function as heat radiating members for transmitting and dissipating the heat generated in the inverter devices 7A and 7B to the treated liquid. As a result, a cooling device (for example, a cooling fin or a cooling fan) required in a conventional motor pump is not required, so that it is possible to suppress an increase in the size of the pump device 100 and increase in manufacturing cost. Furthermore, 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 a heat radiation fin (heat radiation member) 50A arranged in a flow path 27Ad of an inverter casing 27A. Similarly, the second stage pump unit 1B may have a heat radiation fin (heat radiation member) 50B arranged in the flow path 27Bd of the inverter casing 27B. The radiation fin 50B has the same configuration as the radiation fin 50A, so a redundant explanation thereof will be omitted.

The radiation fin 50A is a plate member that protrudes from the inner surface of the inner cylinder 27Aa of the inverter casing 27A into the flow path 27Ad. The radiation fins 50A can radiate heat generated from the inverter device 7A and the motor stator 6A to the handled liquid flowing through the flow path 27Ad via the inner cylinder 27Aa of the inverter casing 27A. Therefore, the inverter device 7A and the motor stator 6A can be further efficiently cooled by the radiation fins 50A.

The radiation fins 50A preferably have high thermal conductivity in order to efficiently dissipate heat to the liquid to be handled. For example, the radiation fins 50A are made of metal such as stainless steel.

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

Furthermore, it is preferable that the radiation fins 50A extend 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 handled 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 a pump device according to yet another embodiment. Pump device 100 shown in FIG. 12 also has a configuration that efficiently cools inverter devices 7A, 7B and motor stators 6A, 6B. Note that configurations that are not particularly described in this embodiment are the same as those in the embodiment shown in FIG. 10, and thus redundant description thereof will be omitted.

The pump device 100 shown in FIG. 12 has at least one inverter chamber inlet hole for allowing the treated liquid to flow into the inverter chambers 27Ae, 27Be instead of the diffusers 21, 22A. In this 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 do not short-circuit. .

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

In this embodiment as well, unless otherwise specified, the inverter casing 7B has the same configuration as the inverter casing 7A described below, and thus the duplicated explanation will be omitted.

A plurality of opening holes 53A are formed in the first stage pump unit 1A shown in FIG. 12 for allowing the treated 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 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 inverter chamber 27Ae of the inverter casing 27A communicates with the suction passage 4c of the suction casing 4 through the opening hole 53A. Therefore, a part of the handled liquid flowing through the suction channel 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 through which the handling liquid sucked from the suction port 4a flows into the inverter chamber 27Ae. The inverter device 7A is immersed in the handling liquid that has flowed into the inverter chamber 27Ae from the suction channel 4c through the opening hole 53A.

The heat generated in the inverter device 7A is transmitted to the handling liquid filling the inverter chamber 27Ae, increasing the temperature of the handling liquid. However, during operation of the pump device 100, the handled liquid in the inverter chamber 27Ae always directly exchanges heat with the lower temperature handled liquid flowing through the suction passage 4c of the suction casing 4, and as a result, the inverter device 7A cooled down.

Furthermore, 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 in the motor stator 6A is transmitted from the protrusion 25A to the inverter casing 27A. Since the inverter chamber 27Ae of the inverter casing 27A is filled with the liquid to be handled, the heat transferred from the protrusion 25A of the motor stator 6A to the inverter casing 27A is efficiently dissipated to the liquid in the inverter chamber 27Ae. As a result, the motor stator 6A can be efficiently cooled.

Similarly, the second stage pump unit 1B is formed with a plurality of opening holes (inverter chamber inlet holes) 53B for allowing the handled liquid to flow into the inverter chamber 27Be. communicates with the communication channel 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 operation of the pump device 100, the handled liquid in the inverter chamber 27Be always directly exchanges heat with the lower temperature handled liquid flowing through the communication channel 26A, so that the inverter device 7B is cooled. Furthermore, 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 through the inverter casing 27B into the inverter chamber 27Be. is efficiently dissipated into the handling liquid. 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 entrance hole. Furthermore, one or more opening holes 53A functioning as inverter chamber inlet holes may be communicated 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 channel 26A and function as inverter chamber entrance 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 entrance hole. Furthermore, one or more opening holes 53B functioning as inverter chamber entrance holes may be communicated with the flow path 27Be of the inverter casing 27B.

In this way, in this embodiment, the inverter devices 7A, 7B and the motor stators 6A, 6B can be efficiently operated with a simple configuration in which the opening holes (inverter chamber inlet holes) 53A, 53B are provided in each pump unit 1A, 1B. can be cooled down. As a result, a cooling device (for example, a cooling fin or a cooling fan) required in a conventional motor pump is not required, so that it is possible to suppress an increase in the size of the pump device 100 and increase in manufacturing cost. Furthermore, 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 handling liquid that has passed through the suction port 4a is actively guided by the guide member 15 described above so as to pass through the opening hole (inverter chamber entrance hole) 53A. Therefore, the guide member 15 always creates a flow of low-temperature handling liquid above the opening hole 53A, thereby efficiently cooling the inverter device 7A and the motor stator 6A. Furthermore, 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 disposed therein. Similarly, the inverter device 7B may have a power element module 29B disposed therein.

FIG. 13 is a schematic cross-sectional view for explaining a modification of the pump device shown in FIG. 12. FIG. 13 shows an enlarged view of the inverter casing 27A and motor casing 3A of the first stage pump unit 1A. Although not shown, the inverter casing 27B and motor casing 3B of the pump units 1B after the first stage pump unit 1A may also have the same configuration as that shown in FIG. 13. The configuration of this embodiment, which will not be particularly described, is the same as the configuration of the pump device 100 shown in FIG. 12, and thus the redundant explanation will be omitted.

In the embodiment shown in FIG. 13, a plurality of opening holes 53A functioning as inverter chamber entrance 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.

Furthermore, at least one opening hole 54A is formed in the bottom wall 27Ac of the inverter casing 27A. As shown in FIG. 13, motor casing 3A is connected to inverter casing 27A. More specifically, motor casing 3A is connected to bottom wall 27Ac of inverter casing 27A. Therefore, the motor chamber 33A communicates with the inverter chamber 27Ae through the opening hole 54A. The opening hole 54A formed in the bottom wall 27Ac functions as at least one communication hole for causing 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 transmitted to the handling liquid that has flowed into the motor chamber 33A via the communication hole 54A, and further to the handling liquid in the inverter chamber 27Ae. However, since the handled liquid in the inverter chamber 27Ae always directly exchanges heat with the lower temperature handled liquid flowing through the flow path 27Ad of the inverter casing 27A, it is not possible to efficiently cool the inverter device 7A and the motor stator 6A. Can be done. In this 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 functioning 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 through which the handling liquid flowing through the flow path 3Aa of the motor casing 3A flows into the motor chamber 33A. In this case, the inverter chamber 27Ae is filled with handling liquid flowing from the flow path 27Ad of the inverter casing 27A through the opening hole 53A, and the motor chamber 33A is filled with handling liquid flowing from the flow path 3Aa of the motor casing 3A through the opening hole 37A. filled with liquid.

In one embodiment, an opening hole 40A may be formed in the partition wall 32A of the motor casing 3A. As described above, the pressure of the handled liquid discharged from the impeller 14A is higher than the pressure of the handled liquid before being sucked into the impeller 14A (i.e., the handled liquid flowing through the channels 4c, 27Ad, 3Aa, and 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, in this embodiment as well, the opening hole 40A formed in the partition wall 32A serves as a motor chamber 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. Functions as an entrance hole.

By the handling liquid that has flowed into the motor chamber 33A through the opening hole (motor chamber inlet hole) 40A, the handling liquid that has filled the motor chamber 33A is pushed out through the communication hole 54A and into the inverter chamber 27Ae of the inverter casing 27A. The handling liquid that has flowed into the inverter chamber 27Ae through the communication hole 54A pushes out the handling liquid that had filled the inverter chamber 27Ae through the opening hole 53A into the flow path 27Ad of the inverter casing 27A. That is, the above-mentioned opening hole 53A functions as an inverter chamber outlet hole for the handling liquid that flows into the inverter chamber 27Ae from the communication hole 54A and is discharged to the flow path 27Ad of the inverter casing 27A. According to such a configuration, while the impeller 14A is rotating, that is, while the pump device 100 is operating, the handled liquid in the motor chamber 33A and the inverter chamber 27Ae is always kept at a low temperature flowing through the opening hole 40A. It can be replaced with the handling liquid. 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 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 that allows the handled liquid to be simultaneously and easily guided 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. 13. The configuration of this embodiment, which is not particularly described, is the same as that of the embodiment shown in FIG. 13, so the redundant explanation 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 opens to a flow path 4c formed in the suction casing 4. Through this 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 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 this 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 can be efficiently operated. Can be cooled.

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

Furthermore, an 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 passes through the opening hole 40A, flows into the motor chamber 33A filled with handling liquid, and further flows into the inverter chamber 27Ae through the opening hole 54A. can.

By the handling liquid that has flowed into the motor chamber 33A through the opening hole (motor chamber inlet hole) 40A, the handling liquid that has filled the motor chamber 33A is pushed out through the communication hole 54A and into the inverter chamber 27Ae of the inverter casing 27A. The handling liquid that has flowed into the inverter chamber 27Ae through the communication hole 54A pushes out the handling liquid that had filled the inverter chamber 27Ae through the opening hole 53A into the flow path 27Ad of the inverter casing 27A. 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 used for handling liquid that flows into the inverter chamber 27Ae from the communication hole 54A and is discharged into the flow path 27Ad of the inverter casing 27A. Functions as an inverter chamber outlet hole for liquid. According to such a configuration, while the impeller 14A is rotating, that is, while the pump device 100 is operating, the handled liquid in the motor chamber 33A and the inverter chamber 27Ae is always kept at a low temperature flowing through the opening hole 40A. It can be replaced with the handling liquid. Therefore, the motor stator 6A and the inverter device 7A can be cooled more efficiently.

FIG. 16 is a schematic diagram showing an example of a water supply device equipped with the pump device 100 according to the embodiment described above. The water supply device is, for example, a device for supplying water to buildings such as office buildings and condominiums.

A water supply device 200 shown in FIG. 16 includes the pump device 100 according to the embodiment described above. In this 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 pipe 209 via a suction pipe 219. A discharge port 16 formed in the pump unit 1C located at the rearmost stage of the pump device 100 is connected to a water supply pipe 207 via a drain pipe 220. This water supply pipe 207 communicates with a water supply valve (faucet, etc.) of a building (not shown).

In FIG. 16, illustration of drive circuits 7A, 7B, 7C that adjust the operating speed of each pump unit 1A, 1B, 1C is omitted, but these drive circuits 7A, 7B, 7C are , 1C (see FIGS. 3(a) to 3(c)), or may be built into each pump unit 1A, 1B, 1C (FIGS. 10, 12, 1C). 13, FIG. 14, and FIG. 15).

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

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

A check valve 222 and a flow switch 224 are attached to the drain pipe 220. Discharge pressure sensor 226 and pressure tank 223 are connected to 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 this embodiment detects that the flow rate of water discharged from the plurality of pump units 1A, 1B, and 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, and 1C.

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

Power lines (lead wires) 17A, 17B, 17C extending from a power source (commercial power source) 9 are connected to each pump unit 1A, 1B, 1C. Earth leakage circuit breakers (ELBs) 238 are provided on the power lines 17A, 17B, and 17C, respectively.

Although not shown, if the drive circuits 7A, 7B, 7C are arranged outside each pump unit 1A, 1B, 1C, the drive circuits 7A, 7B, 7C are connected to the earth leakage breaker 238 and each pump unit 1A. , 1B, and 1C on power lines 17A, 17b, and 17C.

Pump units 1A, 1B, and 1C have temperature sensors 18A, 18B, and 18C that measure the temperatures of 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, temperature sensors 18B and 18C are also attached to motor stators 6B and 6C, respectively. The temperature sensors 18A, 18B, and 18C send their measured values to the control unit 8.

Furthermore, as shown in FIGS. 9, 12, 13, 14, and 15, the first stage pump unit 1A may include a vibration sensor 20A that detects vibrations of the first stage pump unit 1A. The vibration sensor 20A detects vibrations generated during 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 this embodiment, the vibration sensor 20A is arranged in the inner cylinder 30A of the motor casing 3A, and is connected to the control section 8. The vibration sensor 20A sends its measured value to the control unit 8. Similarly, the second-stage pump unit 1B and the third-stage pump unit 1C also measure the vibrations that occur during the operation of the second-stage pump unit 1B and the vibrations that occur during the operation of the third-stage pump unit 1C, respectively. It may also include a vibration sensor. These vibration sensors are also connected to the control section 8 and send their measured values to the control section 8.

The control unit 8 includes a first storage device 227 that stores various setting values and programs necessary for operating the water supply device 200, and a processing device that executes calculations according to instructions included in the programs stored in the first storage device 227. (for example, a CPU) 228. The flow switch 224, the discharge pressure sensor 226, and the temperature sensors 18A, 18B, and 18C are connected to the control unit 8 by signal lines. When the vibration sensors described above (see vibration sensors 20A shown in FIGS. 9, 12, 13, 14, and 15) are provided in the pump units 1A, 1B, and 1C, these vibration sensors are also connected to the control unit by signal lines. Connected to 8.

The drive circuits 7A, 7B, and 7C of each pump unit 1A, 1B, and 1C are connected to the control section 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 connected to each drive circuit 7A, 7B, 7C. The control unit 8 and each of the drive circuits 7A, 7B, and 7C perform communication for transmitting and receiving various commands and various setting values.

The control unit 8 performs water supply through automatic operation, which will be described below. In automatic operation, the plurality of pump units 1A, 1B, and 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 and 1C are basically started alternately. be done. When all of the plurality of pump units 1A, 1B, and 1C are stopped, the first stage pump unit 1A is stopped last. The control unit 8 controls the operation of the pump units 1B and 1C other than the first-stage pump unit 1A so that the number of times of operation and the stop time of each 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 necessary for operation of the water supply device 200.

Next, an example of the 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 installed in the water supply device 200 shown in FIG. 16, and FIG. 2 is a flowchart for explaining an example of a stopping operation.

As shown in FIG. 17, when all the pump units 1A, 1B, and 1C are in a stopped state, the control unit 8 monitors whether a predetermined starting condition is satisfied (see step 1). For example, the control unit 8 monitors whether the discharge pressure measured by the discharge pressure sensor 226 is equal to or lower than a predetermined starting pressure. When water in the building is used when all pump units 1A, 1B, 1C are in a stopped state, the water held in the pressure tank 223 is supplied to the building. The pressure tank 223 functions to prevent frequent starting and stopping of the pump units 1A, 1B, and 1C, and to maintain smooth changes in water supply pressure. As more water is used in the building, the water in the pressure tank 223 decreases, resulting in the discharge pressure dropping below the 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 decreases to a predetermined starting pressure or less.

When the predetermined starting condition is satisfied (see YES in step 1), the control section 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 suction performance that allows the handling liquid to be transferred at a desired flow rate to the second stage pump unit 1B following the first stage pump unit 1A. It is preferable that the control unit 8 stores the operating speed of the first-stage pump unit 1A at startup as a set value necessary for operating the water supply device 200.

During operation of the first stage pump unit 1A, the control unit 8 executes estimated terminal pressure constant control or 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 controlled to be constant so as to maintain a predetermined target value (set pressure). In the estimated terminal pressure constant control, the control unit 8 maintains the water pressure (terminal pressure) at the terminal water faucet in the building at a predetermined pressure (set pressure) by appropriately changing the target value of the discharge pressure. Control as follows.

If the demand for water at the water supply destination increases while the first-stage pump unit 1A is in operation, the control section 8 additionally operates one of the standby pump units 1B and 1C. Specifically, after starting the first stage pump unit 1A, the control unit 8 monitors whether a condition for determining whether or not to additionally operate the next pump unit is satisfied (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 the next pump unit starting condition in advance as a set value necessary for 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 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 a threshold value of the operating speed of the first stage pump unit 1A as a next pump unit starting condition. 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 starting condition is satisfied.

Alternatively, the control unit 8 may previously store a threshold value of the discharge pressure as the next pump unit starting condition. During operation of the first stage pump unit 1A, when the demand for water at the water supply destination increases, the discharge pressure decreases. The control unit 8 determines that the next pump unit starting condition is satisfied when the discharge pressure falls below the threshold value.

When the next pump unit starting condition is satisfied (see YES in step 3), the control section 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, 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 and starts the next pump unit so that the pump units 1B and 1C are started alternately. .

Even while the first stage pump unit 1A and the next pump unit 1B (or 1C) are operating, the control unit 8 performs estimated terminal pressure constant control or discharge pressure constant control based on the measured value of the discharge pressure sent from the discharge pressure sensor 226. Execute.

When the demand for water at the water supply destination increases further, the control unit 8 additionally operates the pump unit 1C (or 1B) that is on standby. Specifically, after starting the first pump unit 1A and the next pump unit 1B (or 1C), the control unit 8 determines whether conditions for determining whether to additionally operate the pump units one after another are satisfied. (See step 5). Hereinafter, the conditions for determining whether or not to additionally operate the pump units one after another will be referred to as "successive pump unit starting conditions." The control unit 8 stores in advance the pump unit starting conditions one after another as set values necessary for operation of the water supply device 200.

The successive pump unit starting 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 increases while the first stage pump unit 1A and the next pump unit 1B (or 1C) are operating, the operating speed of the next pump unit 1B (or 1C) increases. The control unit 8 stores in advance a threshold value of the operating speed of the next pump unit 1B (or 1C) as a successive pump unit starting condition. 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 condition is satisfied one after another.

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

When the pump unit starting conditions are satisfied one after another (see YES in step 5), the control section 8 starts the pump units one after another (see step 6). The successive pump unit is a pump unit different 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 pump unit 1B (or 1C), the next pump unit is pump unit 1C (or 1B).

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

Next, the stopping operation of the pump device 100 will be explained with reference to FIG. 18. If 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, after all the pump units 1A, 1B, and 1C start operating, the control unit 8 determines that the conditions for determining whether to stop the pump units 1C (or 1B) one after another are satisfied. (See step 7). Hereinafter, the conditions for determining whether to stop the pump units 1C (or 1B) one after another will be referred to as "sequential pump unit stop conditions." The control unit 8 stores in advance the conditions for stopping the pump units one after another as set values necessary for operation of the water supply device 200.

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

Alternatively, the control unit 8 may store in advance a threshold value of the discharge pressure as a condition for stopping the pump units one after another. During operation of all pump units 1A, 1B, and 1C, when the demand for water at the water supply destination decreases, 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 above the threshold value. When the pump unit stop conditions are satisfied one after another (see YES in step 7), the control section 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, while the first stage pump unit 1A and the next pump unit 1B (or 1C) are in operation), if the demand for water at the water supply destination further decreases, the control unit 8 stops the next pump unit 1B (or 1C). Specifically, after stopping the pump units 1C (or 1B) one after another, the control unit 8 monitors whether a condition for determining whether to stop the next pump unit is satisfied or not. (see step 9). Hereinafter, the conditions for determining whether to stop the next pump unit 1B (or 1C) will be referred to as "next pump unit stop conditions." The control unit 8 stores the next pump unit stop condition in advance as a set value necessary for 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. When the demand for water at the water supply destination decreases while the first stage pump unit 1A and the next pump unit 1B (or 1C) are operating, the operating speed of the next pump unit 1B (or 1C) decreases. The control unit 8 stores in advance a threshold value of the operating speed of the next pump unit 1B (or 1C) as a next pump unit stop condition. When the operating speed of the next pump unit 1B (or 1C) falls below the threshold value, the control unit 8 determines that the next pump unit stop condition is satisfied.

Alternatively, similarly to the successive pump unit stop condition, the control unit 8 may previously store a threshold value of the discharge pressure as the next pump unit stop condition. During operation of the first stage pump unit 1A and the next pump unit 1B (or 1C), when the demand for water at the water supply destination decreases, 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 section 8 stops the next pump unit 1B (or 1C) (see step 10).

After stopping the next pump unit 1B (or 1C) (that is, while only the first pump unit 1A is in operation), if the water usage at the water supply destination further decreases (for example, the water usage at the water supply destination decreases). (when the first stage pump unit 1A is stopped), the control section 8 stops the first stage pump unit 1A. Specifically, after stopping the next pump unit 1B, the control unit 8 monitors whether a predetermined condition for determining whether to stop the first stage pump unit 1A is satisfied. (See step 11). Hereinafter, a predetermined condition for determining whether to stop the first stage pump unit 1A will be referred to as a "full stop condition". The control unit 8 stores the full stop condition in advance as a set value necessary for operation of the water supply device 200.

The complete stop condition is, for example, whether or not an insufficient flow rate detection signal transmitted from the flow switch 224 is received. When the use of water at the water supply destination decreases, the flow rate of water flowing through the plurality of pump units 1A, 1B, and 1C decreases. When the flow switch 224 detects that the flow rate of water flowing through the plurality of pump units 1A, 1B, and 1C has decreased to a predetermined value or less (insufficient flow rate), it sends an insufficient flow detection signal to the control unit 8. When the control unit 8 receives this low flow rate detection signal, the control unit 8 determines that the full stop condition is satisfied.

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

When the full stop condition is met (see YES in step 11), the control unit 8 performs a pressure accumulation operation in which the rotational speed of the first stage pump unit 1A is temporarily increased until the discharge pressure reaches a predetermined stop pressure, and the pressure tank After the pressure is accumulated at 223, the first stage pump unit 1A is stopped. Such a stopping operation of the first stage pump unit 1A is called a small water flow stopping operation. Further, a state in which all the pump units 1A, 1B, and 1C are stopped in the small water flow stopping operation is referred to as a small water flow stopping state.

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

In this manner, in the automatic operation control of the pump device 100 of the water supply device 200, when a predetermined starting condition is satisfied, the first stage pump unit 1A is started first. Furthermore, 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 stopped last.

As shown in FIG. 16, the control unit 8 includes 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 Temperature signal input terminals 235 are provided to which signal lines extending from the sensors 18 are connected. The measured value of the discharge pressure, the low flow rate detection signal, and the measured value of the temperature of each pump unit 1 are sent to the processing device 228 of the control unit 8 through the pressure signal input terminal 233, the flow rate signal input terminal 234, and the temperature signal input terminal 235. It is now entered into When the measured temperature values of the pump units 1 sent from the temperature sensors 18 exceed the upper limit, the control unit 8 detects an abnormality of pump overheating and abnormally stops the operation of the corresponding pump unit 1. .

In this embodiment, an abnormal stop refers to forcing the pump unit 1 in which an abnormality has occurred to become inoperable. Specifically, when the pump unit 1 in operation is abnormally stopped, the operation of the pump unit 1 is stopped. If the stopped pump unit 1 is brought to an abnormal stop, the pump unit 1 is kept in a stopped state and cannot be started.

The control unit 8 is connected to a power line 242 that branches from a power line extending from the power source 9, and power is supplied to the control unit 8 through the power line 242. The control section 8 includes a power switch 243, and when the power switch 243 is turned on, power is supplied to the control section 8 through the power line 242. The control unit 8 sends an operation signal, which is an ON/OFF signal indicating whether each pump unit 1 is in operation (on/off of each pump unit 1), and a failure signal that indicates a failure of each pump unit 1, etc. It further includes 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 breaker 238 is connected. When the earth leakage breaker 238 detects an earth leakage, the earth leakage breaker 238 issues a trip signal to the control unit 8 . This trip signal is input to the processing device 228 of the control section 8 through the trip signal input terminal 239. When the control unit 8 receives the trip signal from the earth leakage circuit breaker 238, it determines that an abnormality has been detected and abnormally stops the operation of the corresponding pump unit 1.

Furthermore, current sensors (current detection means) 251 are arranged on the power lines 17A, 17B, and 17C that supply current to the drive circuits 7A, 7B, and 7C, respectively. These current sensors 251 measure the value of the current flowing through each pump unit 1, respectively. These current sensors 251 are also connected to the control unit 8 and send measured values of the currents flowing through the power lines 17A, 17B, and 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 to avoid complicating the diagram. 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 section 8 . Note that 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 section 8, and is sent to the processing device 228. is input.

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.

Furthermore, if the pump device 100 has vibration sensors 20 that measure the vibrations of each pump unit 1, these vibration sensors 20 are also connected to the control section 8 and send measured values of vibration to the control section 8. The vibration measurement values sent to the control unit 8 are 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 vibrations generated in the pump unit 1 during operation. For example, if a problem occurs in the impeller 14 and/or the bearing 10, the amplitude and acceleration of vibrations generated in the pump unit 1 will increase. Therefore, when the vibration measurement value (measurement value of vibration amplitude, direction, and/or acceleration) transmitted from the vibration sensor 20 exceeds a predetermined threshold, the control unit 8 detects a vibration abnormality. As a result, the corresponding pump unit 1 is abnormally stopped.

In this way, the control section 8 is configured to be able to detect an abnormality occurring in each pump unit 1 for each pump unit 1. The control unit 8 abnormally stops only the pump unit 1 in which an abnormality has occurred among the plurality of pump units 1A, 1B, and 1C. Since the water supply device 200 that supplies water to buildings is a lifeline, it is desirable to avoid water outages as much as possible. According to the water supply device 200 including the pump device 100 according to the present embodiment, by operating a pump unit 1 different from the pump unit 1 in which the abnormality has occurred, tap water, which is the handled liquid, can be supplied to the building. I can continue. An example of this operation control operation will be explained below.

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. If the abnormally stopped pump unit 1B (or 1C) is in operation, the control unit 8 continues to operate the first stage pump unit 1A while controlling the abnormally stopped pump unit 1B (or 1C). Start a different pump unit 1C (or 1B).

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

When the abnormally stopped pump unit is the first stage pump unit 1A, the control section 8 abnormally stops all the pump units 1A, 1B, and 1C. 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, although the flow rate of water that can be supplied to the water supply destination may be smaller than the desired flow rate, it is possible to prevent water outages in the building.

In one embodiment, the control unit 8 stores a first threshold value for causing an emergency stop of each pump unit 1 due to overheating, and the control unit 8 stores a first threshold value for causing an emergency stop of each pump unit 1 due to overheating. When the measured temperature value exceeds this first threshold value, the corresponding pump unit 1 is brought to an emergency stop.

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

Further, the control unit 8 starts the pump units 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 that has been abnormally stopped due to temperature abnormality can be quickly lowered.

The control unit 8 may have a third threshold value that is lower than the second threshold value. The third threshold is a temperature at which the pump unit 1 that has been abnormally stopped due to temperature abnormality can be restarted, and is sometimes referred to as a "return temperature." When the temperature of the pump unit 1 that has been abnormally stopped becomes equal to or lower than the third threshold value, the control section 8 cancels the abnormal stop of the pump unit 1 concerned. As a result, all pump units 1 can be operated.

In order to avoid water outage 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. Furthermore, 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, it becomes possible to operate the first stage pump unit 1A with sufficient margin, and it is expected that the life of the first stage pump unit 1A will be extended.

Some users of the water supply device 200 may wish to continue operating the water supply device 200 as much as possible. In this case, the control section 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 section 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 an emergency stop is performed.

As shown in FIG. 16, the pump device 100 mounted on the water supply device 200 may further include an operating device 247 connected to the control unit 8. In this embodiment, the operating device 247 is placed on the control unit 8, but as long as it is electrically connected to the control unit 8, the operating device 247 may be placed apart from the control unit 8. For example, the operating device 247 may be an external display that is connected to the control unit 8 through wireless communication such as near field communication (NFC) or BLUETOOTH (registered trademark), or wired communication such as a wired network or serial communication. It may be a container (not shown). The operating device 247 shown in FIG. 16 includes an operation selector switch 252 for selecting test/stop/automatic operation of each pump unit 1, a lamp 253 for indicating operation/failure, and various setting values ( For example, the control unit 255 includes an operation unit 255 as an input device having an operation button 254 for inputting a discharge pressure (for example, discharge pressure, etc.) to the control unit 8. Further, the operating device 247 includes a display device 256 such as a liquid crystal display for displaying information regarding the water supply and the drive circuits 7A, 7B, and 7C. The operating unit 255 as an input device and the display device 256 have an integrated configuration, but in one embodiment, the operating unit 255 and the display device 256 may be arranged separately.

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

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

FIG. 19 is a schematic diagram showing another example of a water supply device equipped with the pump device according to the embodiment described above. More specifically, FIG. 19 is a schematic diagram showing an example of a water supply device 200 equipped with a plurality of pump devices 100 according to the embodiment described above. The configuration of this embodiment, which is not particularly described, is the same as the configuration of the water supply device 200 shown in FIG. 16, and therefore, the redundant explanation will be omitted.

Each pump device 100 shown in FIG. 19 includes a plurality of pump units 1A, 1B, and 1C having the same configuration as the pump device 100 shown in FIG. 16. 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 a branch drain pipe 220A. The branch drain pipe 220A joins the drain collection pipe 220.

Each pump device 100 includes the check valve 222 and flow switch 224 described above. 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 flow switch 224 of each pump device 100 are attached to the branch suction pipe 219A, and the discharge pressure sensor 226 and 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 section 8 having the same configuration as the control section 8 described with reference to FIG. 16, and this control section 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 for each pump device 100. In one embodiment, each pump device 100 may have a dedicated control 8. In this case, each control unit 8 is configured to be able to send 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 tank 206, and the water supply device 200 transfers the tap water stored in the water tank 206 to a destination (for example, a water tap in a building). Transport. The water tank 206 is connected to a water pipe 209 via an introduction pipe 210, and water flowing through the water pipe 209 is transferred to the water tank 206 through the introduction pipe 210.

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

The water supply device 200 of this embodiment uses the plurality of pump units 1A, 1B, and 1C of each pump device 100 to transfer tap water stored in a water receiving tank 206 to a destination. As described above, the first stage pump unit 1A has suction performance that allows the handling liquid to be transferred at a desired flow rate to the second stage pump unit 1B following the first stage pump unit 1A. 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 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 destination can be transferred to the destination at a desired pressure.

Each pump device 100 is operated with the starting and stopping operations described with reference to FIGS. 17 and 18. Further, the control unit 8 is configured to be able to detect abnormalities occurring in each pump device 100 for each pump unit 1. Although the pump unit 1 in which an abnormality has been detected is abnormally stopped, tap water can be transferred to a destination such as a water tap in a building using another pump unit 1. Therefore, water outage in the building is prevented.

In this embodiment, the water supply device 200 includes a plurality of (two in FIG. 19) pump devices 100 that are operated in this manner. While one pump device 100 is in operation, the other pump device 100 is on standby as a backup pump device. In the water supply device 200 equipped with three or more pump devices 100, at least one pump device 100 is preferably in a standby state as a backup pump device. The control unit 8 controls the operation of these pump devices 100 so that the number of times the pump devices 100 are operated and the stop time of each pump device 100 are equalized. For example, when the water supply device 200 has two pump devices 100, the control unit 8 operates these pump devices 100 alternately.

According to the water supply device 200 according to this embodiment, each pump device 100 can be expected to have a longer lifespan. Furthermore, even if one pump device 100 becomes inoperable, tap water can be transferred to the building using another pump device 100. Therefore, water outage in the building can be prevented.

In one embodiment, one pump device 100 among the plurality of pump devices 100 may be always on standby as an emergency pump device. The 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 a water outage from occurring in the building.

The embodiments described above have been described to enable those skilled in the art to carry out the invention. Various modifications of the above embodiments 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 invention is not limited to the described embodiments, but is to be construed in the broadest scope according to the spirit 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 part 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 Projection 26A, 26B, 26C Communication passage 27A, 27B Circuit casing (inverter casing)
33A, 33B, 33C Motor chamber 37A, 37B, 37C Opening hole 40 Opening hole 50A, 50B Heat radiation fin (heat radiation member)
53A, 53B Opening hole 54A, 54B Opening hole 100 Pump device 200 Water supply device 224 Flow switch 226 Pressure sensor 251 Current detector

Claims (13)

A pump device for transferring handling liquid,
multiple pump units connected in series,
a control unit that controls operations of the plurality of pump units;
a flow rate detector that detects a small water flow state in which the flow rate of the handling liquid discharged from the final stage pump unit located at the rearmost stage of the plurality of pump units is less than or equal to a predetermined small water volume;
A pressure sensor that measures the discharge side pressure of the final stage pump unit,
Each pump unit is
an impeller in which a magnet is buried;
a motor stator disposed at a position facing the magnet;
a pump casing that houses the impeller;
a motor casing that accommodates the motor stator;
The pump unit located at the forefront of the plurality of pump units is a first stage pump unit,
The control unit includes:
activating at least one pump unit of the plurality of pump units when the discharge side pressure falls below a predetermined starting pressure;
When the low water flow state is detected, automatic operation control is performed to stop the activated pump unit with a low water flow;
The control unit includes:
It is configured so that abnormalities occurring in each pump unit can be detected for each pump unit,
The pump device is characterized in that, among the plurality of pump units, the automatic operation control is performed except for a pump unit in which an abnormality has occurred . The pump device according to claim 1, wherein the control unit abnormally stops a pump unit in which an abnormality has occurred among the plurality of pump units. The pump device according to claim 2, wherein the control section abnormally stops all pump units of the plurality of pump units when the pump unit in which the abnormality has occurred is the first stage pump unit. The pump according to claim 3, wherein when an abnormality occurs in a pump unit other than the first-stage pump unit among the plurality of pump units, the control unit abnormally stops only the pump unit in which the abnormality has occurred. Device. The pump device further includes a temperature sensor that measures the temperature of each pump unit,
5. The abnormality detectable for each pump unit is a temperature abnormality in which the measured value of the temperature sensor is higher than a predetermined first threshold value. Pump device described in. When the measured value of the temperature sensor of a second pump unit different from the first stage pump unit reaches a second threshold value set lower than the first threshold value, the control unit Stops the pump unit abnormally,
6. The pump device according to claim 5, wherein at least the first stage pump unit is operable. After the second pump unit is abnormally stopped, when the measured value of the temperature sensor of the second pump unit decreases to a third threshold value that is set lower than the second threshold value, the The pump device according to claim 6, wherein the control section releases the abnormal stop of the second pump unit. The pump according to claim 6, wherein the control unit continues to operate the first stage pump unit even if the measured value of the temperature sensor of the first stage pump unit reaches the second threshold. Device. The pump device further includes current detection means for measuring the current value supplied to each pump unit,
The control unit monitors the measured value of the current detection means,
The pump according to any one of claims 1 to 8, wherein the abnormality that can be detected for each pump unit is an overcurrent abnormality in which a measured value of the current detection means is equal to or higher than a predetermined limit value. Device. The pump device according to claim 9, wherein the limit value of the first-stage pump unit is different from the limit value of pump units other than the first-stage pump unit. The pump device according to any one of claims 3 to 10, wherein the rated capacity of the first stage pump unit is larger than the rated capacity of pump units other than the first stage pump unit. The pump device according to any one of claims 3 to 11, wherein the first stage pump unit has higher suction performance than pump units other than the first stage pump unit. Each pump unit further includes an inverter device that controls the impeller at variable speed,
13. The pump device according to claim 12, wherein the operating speed of the first-stage pump unit is slower than the operating speed of pump units other than the first-stage pump unit.

Images