JP6466292B2 - Submersible electric pump - Google Patents

Description

  The present invention relates to a submersible electric pump.

  Conventionally, a small submersible electric pump including an oil chamber in which a mechanical seal is provided between the pump chamber and the motor is known so that the pressure water in the pump chamber does not enter the motor. However, this submersible electric pump has a disadvantage that pressure water, oil, or the like entering the oil chamber from the sliding portion may flow into the motor due to wear or surface roughness of the sliding portion of the mechanical seal.

  Therefore, in order to prevent pressure water, oil, etc. from flowing into the motor, a submersible pump that shuts off the power supply to the motor by installing a submersion detection sensor in the oil chamber and detecting the submersion in the oil chamber. (Submersible electric pump) has been proposed (see, for example, Patent Document 1). In addition, an additional immersion chamber is provided between the oil chamber and the motor to prevent the pressure water in the pump chamber and the oil in the oil chamber from entering the motor, so that the inundation detector can detect inundation in the immersion chamber. Based on this, a submersible pump (submersible electric pump) having a configuration that ensures a long time until the motor is de-energized has also been proposed (see, for example, Patent Document 2).

JP 2002-310091 A JP 2007-332825 A

  However, in the submersible pump (submersible electric pump) of the above-mentioned Patent Document 1, when the water detection sensor detects that the pressure water in the pump chamber has submerged in the oil chamber, the pressure water, oil, or the like flows into the motor. In order to minimize this, it is necessary to forcibly stop the submersible pump, pull it out of the water, remove the pump casing, the oil casing, etc., perform the maintenance work, and restore the pump. In this case, in order to continue the operation, it is necessary to have a spare submersible pump and take emergency measures with the spare submersible pump. For this reason, there is a problem that a lot of labor is required for maintenance.

  Also, in the submersible pump (submersible electric pump) of Patent Document 2, when the pressure water in the pump chamber is submerged in the oil chamber, the submersible pump is forcibly stopped in the same manner as the submersible pump of Patent Document 1. It is necessary to pull it out of the water, remove the pump casing, the oil casing, etc., perform the maintenance work, and restore it. In this case, in order to continue the operation, as in the case of Patent Document 1, it is necessary to make an emergency response with a spare submersible pump, and thus there is a problem that much labor is required for maintenance.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a submersible electric pump that can be easily maintained.

  The submersible electric pump according to one aspect of the present invention is provided with a motor, a pump chamber in which an impeller driven by the motor is disposed, and a mechanical seal having a sliding portion, and is disposed between the motor and the pump chamber. An oil chamber, a fluid return path that communicates between the motor and the oil chamber, a water immersion detection unit that detects water immersion in the oil chamber, and a valve member that is provided integrally with the water immersion detection unit and opens and closes the fluid return path. And a valve member drive mechanism for driving the valve member to open and close the fluid return path.

  In the submersible electric pump according to one aspect of the present invention, as described above, the fluid return path that communicates between the motor and the oil chamber, the submersion detection unit that detects submergence of the oil chamber, and the submersion detection unit are formed integrally. A valve member that opens and closes the fluid return path and a valve member drive mechanism that opens and closes the fluid return path by driving the valve member are provided. Thus, the valve member can be driven by the valve member driving mechanism to open and close the fluid return path, so that the fluid can be returned from the motor side to the oil chamber. As a result, since the fluid rising to the motor side from the oil chamber does not remain, there is no need to perform maintenance work by removing the pump casing or the oil casing. Further, even when fluid rise occurs, it is possible to prevent oil from flowing into the motor bearing and causing the grease of the motor bearing to flow. Moreover, it is not necessary to have a spare submersible pump in order to continue operation. As a result, maintenance and management of the submersible electric pump can be easily performed without requiring much labor and cost for maintenance. Further, since the valve member serves as a check valve, when the fluid return path is closed by the valve member, the fluid can be prevented from flowing back to the motor side through the fluid return path. Further, since the fluid return path that connects the motor and the oil chamber is opened and closed by the valve member, the pressure in the motor and the oil chamber can be made the same. As a result, the pressure between the motor and the oil chamber can be balanced.

  In the submersible electric pump according to the above aspect, the valve member driving mechanism preferably includes an electromagnet that drives the valve member. If comprised in this way, since a valve member can be opened and closed by controlling energization of an electromagnet, a fluid return way can be easily opened and closed by a valve member.

  In this case, preferably, the valve member drive mechanism includes a fixed portion and a movable portion that is moved together with the valve member with respect to the fixed portion, and one of the fixed portion and the movable portion is provided with an electromagnet, and the fixed portion The other of the movable parts is provided with an electromagnet or a permanent magnet, and the valve member drive mechanism is configured to open and close the valve member by moving the movable part relative to the fixed part. If comprised in this way, since a movable part can be easily moved with respect to a fixed part by supplying with electricity to an electromagnet, a fluid return path can be opened and closed easily by a valve member.

  In the submersible electric pump according to the above aspect, the fluid return path is preferably opened by the valve member drive mechanism when the motor is stopped. With this configuration, after the motor is stopped, the fluid return path is opened by the valve member drive mechanism, so that it is possible to prevent the fluid from flowing back through the fluid return path during operation of the submersible electric pump. it can.

  The submersible electric pump according to the above aspect preferably further includes an operation unit that receives a user operation to open and close the valve member by the valve member drive mechanism. If comprised in this way, a valve member can be opened and closed by a user's arbitrary timing by operation of the operation part by a user.

  In the submersible electric pump according to the above aspect, preferably, a fluid reservoir is provided in a lower portion inside the motor, and the valve member drive mechanism is disposed in the fluid reservoir. With this configuration, even when the fluid flows out above the oil chamber, the fluid can be stored in the fluid storage portion, so that the fluid is directly applied to the motor bearings and the power unit (parts of the stator and rotor). ) Can be effectively suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, as mentioned above, the submersible electric pump which can perform maintenance management easily can be provided.

It is the schematic which showed the submersible electric pump by 1st Embodiment of this invention. It is the schematic which showed the closed state of the 1st fluid return path of the submersible electric pump by 1st Embodiment of this invention. It is the schematic which showed the open state of the 1st fluid return path of the submersible electric pump by 1st Embodiment of this invention. It is a flowchart for demonstrating the fluid return process of the submersible electric pump by 1st Embodiment of this invention. It is the schematic which showed the submersible electric pump by 2nd Embodiment of this invention. It is the schematic which showed the submersible electric pump by 3rd Embodiment of this invention. It is an enlarged view of the fluid pressurization part by the modification of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
(Configuration of submersible electric pump)
A first embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the submersible electric pump 100 according to the first embodiment includes a motor 1, a rotating shaft 2, an impeller 3, a pump chamber 4, an oil chamber 5, and sliding portions 6a and 6b. A mechanical seal 6, an annular body 7, a water immersion detection unit 8, and a fluid return unit 9 are provided. A control unit 10 is connected to the submersible electric pump 100. The fluid return unit 9 is configured to return the fluid accumulated in the motor 1 (a fluid storage unit 14 described later) to the oil chamber 5 under the control of the control unit 10. Details will be described later. The submersible electric pump 100 is a vertical submersible electric pump in which the rotary shaft 2 extends in the vertical direction.

  The motor 1 includes a stator 11 and a rotor 12. The motor 1 is sealed so that water from the outside does not enter. Further, the motor 1 is configured to rotationally drive the impeller 3 (rotating shaft 2).

  The stator 11 has a coil. The stator 11 is disposed on the outer periphery of the motor 1. Further, the power is supplied from the cable 13 to the coil of the stator 11 so that a magnetic field is generated. The rotor 12 is disposed inside the motor 1 so as to face the stator 11. The rotor 12 is attached to the rotating shaft 2. The rotor 12 is configured to rotate by a magnetic field from the stator 11.

  In addition, a fluid reservoir 14 is provided in a lower portion inside the motor 1. The fluid storage unit 14 is provided to store the fluid when the fluid containing oil rises.

  The rotating shaft 2 is configured to rotate by driving the motor 1. The rotary shaft 2 is configured to transmit the drive of the motor 1 to the impeller 3. The rotating shaft 2 is configured to rotate clockwise (clockwise) in a plan view (when viewed from above). The rotating shaft 2 is rotatably supported by bearings 21 and 22. The bearing 21 is provided on the opposite side of the motor 1 (the side opposite to the pump chamber 4). The bearing 22 is provided on the load side (pump chamber 4 side) of the motor 1. The rotating shaft 2 is arranged so as to extend from the motor 1 through the oil chamber 5 to the pump chamber 4. An impeller 3 is attached to the end of the rotary shaft 2 on the pump chamber 4 side.

  The impeller 3 is disposed in the pump chamber 4. Moreover, the impeller 3 gives speed energy to water by rotationally driving. And it is comprised so that pressure may be acted on and sent to water, when the velocity energy of water is converted into pressure energy within the pump chamber 4. That is, by the rotational drive of the impeller 3, water is sucked up from the water suction port 41 of the pump chamber 4, and the water sucked up from the discharge port 42 is discharged.

  The oil chamber 5 is disposed between the motor 1 and the pump chamber 4, and the oil chamber 5 is filled with oil. A wall 51 is disposed on the motor 1 side of the oil chamber 5. An oil lifter 52 is provided around the rotation shaft 2 of the oil chamber 5. Also, a mechanical seal 6 having sliding portions 6a and 6b is provided in the oil chamber 5, and the sliding portions 6a and 6b are lubricated by the oil filled in the oil chamber 5, and the sliding portion 6a and 6b are configured to be cooled so as not to burn. Specifically, the sliding portion 6 a on the load side (pump chamber 4 side) of the mechanical seal 6 is provided on the pump chamber 4 side of the oil chamber 5. That is, the sliding portion 6 a on the load side (pump chamber 4 side) of the mechanical seal 6 is provided so that the pressure water in the pump chamber 4 does not enter the oil chamber 5. A sliding portion 6 b on the side opposite to the load side of the mechanical seal 6 (the side opposite to the pump chamber 4) is provided on the motor 1 side of the oil chamber 5. That is, the sliding portion 6b on the side opposite to the load side of the mechanical seal 6 (the side opposite to the pump chamber 4) is provided so that the fluid containing the oil in the oil chamber 5 does not enter the motor 1 side. At least the inner wall 5a of the oil chamber 5 is made of a metal material and serves as one electrode of the inundation detection unit 8. Details will be described together with the description of the inundation detection unit 8.

  The oil lifter 52 is provided in a cylindrical shape around the rotation shaft 2. The oil lifter 52 is configured to lift up the oil that moves as the rotary shaft 2 rotates. That is, the oil lifter 52 is configured to supply oil to the sliding portion 6b. A through hole 521 is provided in the lower part of the oil lifter 52. The oil is guided from the through hole 521 to the inner peripheral side of the oil lifter 52.

  The mechanical seal 6 includes a fixed member 61, a rotating member 62, and a spring 63. The fixing member 61 has a sliding surface 611. The rotating member 62 has a sliding surface 621. The fixing member 61 is fixed to the housing of the oil chamber 5. The fixing member 61 is formed in an annular shape so as to surround the rotating shaft 2. The rotating member 62 is attached to the rotating shaft 2. That is, the rotating member 62 is configured to rotate together with the rotating shaft 2. The rotating member 62 is formed in an annular shape so as to surround the rotating shaft 2. The rotating member 62 is urged toward the fixed member 61 by a spring 63.

  The fixed member 61 and the rotating member 62 are disposed so as to face each other in the axial direction of the rotating shaft 2. In the sliding portions 6a and 6b, the sliding surface 611 of the fixing member 61 and the sliding surface 621 of the rotating member 62 are configured to slide relative to each other. Further, the oil in the oil chamber 5 slightly enters between the sliding surfaces 611 and 621. As a result, the sliding surfaces 611 and 621 are lubricated, cooled by oil so that the sliding surfaces 611 and 621 are not seized, and the sliding portions 6a and 6b (oil chamber 5) are sealed. Has been.

  The annular body 7 is provided so as to protrude from the wall 51 on the side opposite to the load side of the oil chamber 5 (the side opposite to the pump chamber 4) to the motor 1 side. The annular body 7 is provided in an annular shape so as to surround the rotation shaft 2 with a predetermined distance from the rotation shaft 2. A seal 71 is provided at the end of the annular body 7 on the motor 1 side. As the seal 71, for example, an oil seal, a seal lip, or a seal having a mechanism for generating a thrust force on the load side such as an inclined rib or a groove at a lip portion that slides with the rotary shaft 2 is used. The seal 71 is disposed between the annular body 7 and the rotary shaft 2.

  Further, an oil rising channel 72 is formed in the annular body 7 on the motor 1 side with respect to the seal 71. The oil ascending flow path 72 is provided so as to communicate the inside of the annular body 7 (the space between the annular body 7 and the rotary shaft 2) and the motor 1 (fluid reservoir 14). The oil ascending flow path 72 is configured to guide a fluid containing oil flowing out from the oil chamber 5 side through the sliding portion 6 b of the mechanical seal 6 to the fluid storage portion 14. The oil ascending flow path 72 is preferably formed of a through-hole formed in the housing or an opening formed in a groove shape, but may be formed of a pipe member such as a pipe or a tube. The oil ascending flow path 72 is disposed at a position above the fluid storage unit 14.

  The infiltration detection unit 8 is formed in a rod shape extending from the fluid storage unit 14 to the oil chamber 5. Further, the lower end of the inundation detection unit 8 is disposed in the oil of the oil chamber 5. Further, the inundation detection unit 8 is configured to detect inundation from the pump chamber 4 into the oil chamber 5. More specifically, the inundation detection unit 8 is formed of a metal material and includes the other electrode with respect to the inner wall 5a (one electrode) of the oil chamber 5. The inundation detection unit 8 is connected to the pump chamber 4 by connecting the inner wall 5a (one electrode) of the oil chamber 5 and the infiltration detection unit 8 (the other electrode) with an increase in the ratio of water to oil. Is configured to detect water intrusion into the oil chamber 5.

  As shown in FIGS. 2 and 3, the fluid return unit 9 includes a first fluid return path 91, a valve member 92, and a valve member drive mechanism 93. The first fluid return path 91 is an example of the “fluid return path” in the claims.

  The first fluid return path 91 is provided so as to communicate the motor 1 (fluid reservoir 14) with the oil chamber 5. That is, the first fluid return path 91 is provided so as to penetrate the wall 51 in the vertical direction. Moreover, the 1st fluid return path 91 has the return path side inclination part 91a in the oil chamber 5 side (lower side) so that it may spread to the oil chamber 5 side.

  The valve member 92 is provided integrally with the inundation detection unit 8. The valve member 92 is formed of an elastic member such as rubber. Further, the valve member 92 is formed of an insulating member. Further, the valve member 92 is disposed in the oil chamber 5. Further, the valve member 92 has a valve member side inclined portion 92a formed in a shape corresponding to the return path side inclined portion 91a of the first fluid return path 91 on the motor 1 side (upper side). Further, the valve member 92 is configured to open and close the first fluid return path 91 from the oil chamber 5 side by being driven in the vertical direction together with the infiltration detection unit 8 by the valve member driving mechanism 93. Specifically, as shown in FIG. 2, the valve member 92 is moved upward and the first fluid return path 91 is closed. Moreover, as shown in FIG. 3, the valve member 92 is moved downward and the first fluid return path 91 is opened.

  The valve member drive mechanism 93 has a fixed portion 94 that is fixedly provided, and a movable portion 95 that is moved together with the valve member 92 and the water immersion detection portion 8 with respect to the fixed portion 94.

  The movable portion 95 is disposed between the fixed portion 94 and the wall 51. The inundation detection unit 8 is provided with a nut portion 96 between the fixed portion 94 and the movable portion 95, and is configured such that the spring 95c is compressed by tightening the nut portion 96. The valve member 92 is configured to abut against the return path side inclined portion 91a and seal the first fluid return path 91 by a force generated by the spring 95c being compressed by being fastened to the portion 96.

  Both the fixed portion 94 and the movable portion 95 are disposed in the fluid storage portion 14. The fixing portion 94 is provided with an electromagnet 94a. Further, the movable part 95 is provided with a permanent magnet 95a. The valve member driving mechanism 93 is configured to open and close the valve member 92 by moving the movable portion 95 relative to the fixed portion 94 by the electromagnet 94a and the permanent magnet 95a. The electromagnet 94a includes, for example, a coil. Further, for example, the electromagnet 94a and the permanent magnet 95a are both formed in an annular shape so as to surround the shaft portion where the water immersion detection unit 8 is provided.

  The fixed portion 94 has a plate-like member 94b on which the electromagnet 94a is installed. The plate-like member 94b is fixedly installed on the wall 51 through an insulating member 94c. That is, the wall 51 and the plate-like member 94b are insulated by the insulating member 94c. The movable portion 95 includes a plate-like member 95b on which the permanent magnet 95a is installed, and a spring 95c that urges the plate-like member 95b (permanent magnet 95a) from the wall 51 side toward the fixed portion 94 (electromagnet 94a). And an insulating member 95d that insulates the wall 51 (inner wall 5a) and the spring 95c. Further, the electromagnet 94a of the fixed portion 94 and the permanent magnet 95a of the movable portion 95 are arranged at positions facing each other in the vertical direction. The electromagnet 94a is configured to generate a magnetic field when energized. Further, the permanent magnet 95a is disposed so as to have a magnetic pole (S pole or N pole) on the surface facing the electromagnet 94a when the electromagnet 94a is energized. That is, the magnetic field is generated by energizing the electromagnet 94a, and a repulsive force acts between the electromagnet 94a and the permanent magnet 95a.

  The valve member drive mechanism 93 is configured to be opened and closed under the control of the control unit 10.

  Specifically, as shown in FIG. 2, the valve member drive mechanism 93 releases the energization to the electromagnet 94a (extinguishes the magnetic field), thereby moving the movable portion 95 (valve member 92) upward by the spring 95c. It is configured to move (to the fixed portion 94 side). As a result, the valve member 92 is pressed against the first fluid return path 91 to close the first fluid return path 91 (becomes a closed state). In this state, the return path side inclined portion 91a of the first fluid return path 91 and the valve member side inclined portion 92a of the valve member 92 are in contact with each other.

  As shown in FIG. 3, the valve member driving mechanism 93 causes the electromagnet 94a and the permanent magnet 95a to be separated from each other when a repulsive force acts between the electromagnet 94a and the permanent magnet 95a by energizing the electromagnet 94a. Thus, the movable portion 95 (valve member 92) is configured to move downward (to the oil chamber 5 side). As a result, the valve member 92 is separated from the first fluid return path 91 and opens the first fluid return path 91 (becomes an open state).

  As shown in FIG. 1, the control unit 10 is connected to the submersible electric pump 100 via a cable 13. The control unit 10 is provided on a control panel for driving the submersible electric pump 100. The control unit 10 is configured to control the driving of the motor 1. The control unit 10 is configured to control the opening and closing of the fluid return path 91 (the operation of the valve member drive mechanism 93 (see FIGS. 2 and 3)).

(Description of fluid return processing)
Next, the fluid return process of the submersible electric pump 100 of the first embodiment will be described with reference to FIG. The oil return control process is performed by the control unit 10.

  While the submersible electric pump 100 is being driven, it is determined in step S1 whether or not the driving of the submersible electric pump 100 (motor 1) has been stopped. If the driving of the submersible electric pump 100 (motor 1) is not stopped, the determination in step S1 is repeated until the driving is stopped. If the driving of the submersible electric pump 100 (motor 1) is stopped, in step S2, the electromagnet 94a is energized to move the valve member 92 downward, and the first fluid return path 91 is opened.

  In step S3, it is determined whether or not a predetermined time (for example, 30 seconds) has elapsed since the first fluid return path 91 was opened. That is, it is determined whether or not the first fluid return path 91 is opened and the fluid in the fluid reservoir 14 is returned to the oil chamber 5 for a predetermined time. The determination in step S3 is repeated until a predetermined time has elapsed.

  When the predetermined time has elapsed, in step S4, the valve member 92 is moved upward, and the first fluid return path 91 is closed.

(Effect of 1st Embodiment)
In the first embodiment, the following effects can be obtained.

  In the first embodiment, as described above, the first fluid return path 91 that allows the motor 1 and the oil chamber 5 to communicate with each other, the inundation detection unit 8 that detects inundation of the oil chamber 5, and the inundation detection unit 8 are integrated. And a valve member 92 that opens and closes the first fluid return path 91, and a valve member drive mechanism 93 that drives the valve member 92 to open and close the first fluid return path 91. Thus, the valve member 92 can be driven by the valve member drive mechanism 93 to open and close the first fluid return path 91, so that the fluid can be returned from the motor 1 side to the oil chamber 5. As a result, since the fluid rising to the motor 1 side from the oil chamber 5 does not remain, there is no need to perform maintenance work by removing the pump casing, the oil casing, and the like. Further, even when the fluid rises, oil can be prevented from flowing into the bearing 22 of the motor 1 and flowing the grease of the bearing 22 of the motor 1. Moreover, it is not necessary to have a spare submersible pump in order to continue operation. As a result, maintenance and management of the submersible electric pump 100 can be easily performed without requiring much labor and cost for maintenance. Further, since the valve member 92 serves as a check valve, when the fluid return path is closed by the valve member 92, the fluid is prevented from flowing back to the motor 1 side through the first fluid return path 91. Can do. In addition, since the first fluid return path 91 that communicates the motor 1 and the oil chamber 5 is opened and closed by the valve member 92, the pressure of the motor 1 and the oil chamber 5 can be made the same pressure. As a result, the pressure of the motor 1 and the oil chamber 5 can be balanced.

  In the first embodiment, as described above, the valve member driving mechanism 93 is provided with the electromagnet 94a and the permanent magnet 95a for driving the valve member 92. Thereby, since the valve member 92 can be opened and closed by controlling the energization of the electromagnet 94a, the first fluid return path 91 can be easily opened and closed by the valve member 92.

  In the first embodiment, as described above, the valve member driving mechanism 93 is provided with the fixed portion 94 and the movable portion 95 that is moved together with the valve member 92 with respect to the fixed portion 94. Further, the fixed portion 94 and the movable portion 95 are provided with an electromagnet 94a and a permanent magnet 95a, respectively, and the valve member driving mechanism 93 moves the movable portion 95 relative to the fixed portion 94, thereby opening and closing the valve member 92. Configure as follows. Thereby, since the movable part 95 can be easily moved with respect to the fixed part 94 by energizing the electromagnet 94a, the first fluid return path 91 can be easily opened and closed by the valve member 92.

  In the first embodiment, as described above, the first fluid return path 91 is opened by the valve member drive mechanism 93 when the motor 1 is stopped. Thus, after the motor 1 is stopped, the first fluid return path 91 is opened by the valve member drive mechanism 93, so that the fluid flows to the motor 1 via the first fluid return path 91 when the submersible electric pump 100 is operated. Backflow can be prevented.

  Further, in the first embodiment, as described above, the fluid reservoir 14 is provided in the lower portion inside the motor 1, and the valve member drive mechanism 93 is disposed in the fluid reservoir 14. Thereby, even when the fluid flows out above the oil chamber 5, the fluid can be stored in the fluid storage unit 14, so that the fluid directly flows into the bearing 22 or the power unit (the stator 11 and the rotor of the motor 1). 12 portion) can be effectively suppressed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, a configuration in which a fluid pressurizing unit 201 and a second fluid return path 202 are provided in addition to the configuration of the first embodiment will be described.

  As shown in FIG. 5, the submersible electric pump 200 according to the second embodiment includes a motor 1, a rotating shaft 2, an impeller 3, a pump chamber 4, an oil chamber 5, and sliding portions 6a and 6b. A mechanical seal 6, an annular body 7, a water immersion detection unit 8, a fluid return unit 9, a fluid pressurization unit 201, and a second fluid return path 202 are provided. Further, the controller 10 is connected to the submersible electric pump 200. The submersible electric pump 200 is a vertical submersible electric pump in which the rotary shaft 2 extends in the up-down direction.

  Here, in 2nd Embodiment, the fluid pressurization part 201 is arrange | positioned in the space inside the annular body 7. FIG. In addition, the fluid pressurizing unit 201 is disposed between the motor 1 and the oil chamber 5. The fluid pressurizing unit 201 is configured to pressurize the fluid toward the oil chamber 5 side. Further, the fluid pressurizing unit 201 is formed of an annular cylindrical body in which a groove 201a that is inclined with respect to a horizontal plane is formed on the outer peripheral portion. A plurality of (for example, two) groove portions 201a of the fluid pressurizing unit 201 are provided.

  The fluid pressurizing unit 201 is disposed between the motor 1 and the oil chamber 5 and seals between the motor 1 and the oil chamber 5. The fluid pressurizing unit 201 is attached to the rotating shaft 2 that transmits the drive of the motor 1 to the impeller 3. Thereby, the fluid pressurization part 201 is comprised so that it may rotate with the rotating shaft 2. FIG. The fluid pressurizing unit 201 is made of, for example, a rubber material. The groove 201a of the fluid pressurizing unit 201 is formed so as to have a downward slope when viewed from the side.

  Further, in the first embodiment, as shown in FIG. 5, a second fluid return path 202 is formed on the oil chamber 5 side of the annular body 7 from the fluid pressurizing unit 201. The second fluid return path 202 is provided to communicate the inside of the annular body 7 with the oil chamber 5. That is, the second fluid return path 202 is configured to return the fluid containing oil that has risen inside the annular body 7 to the oil chamber 5. In addition, the second fluid return path 202 is preferably configured by a through-hole formed in the housing or an opening formed in a groove shape, but may be configured by a pipe member such as a pipe or a tube. That is, the second fluid return path 202 only needs to be configured so that the fluid pressurization unit 201 (inside the annular body 7) and the oil chamber 5 communicate with each other.

  In addition, the other structure of 2nd Embodiment is the same as that of the said 1st Embodiment.

(Effect of 2nd Embodiment)
In the second embodiment, the following effects can be obtained.

  In the second embodiment, as in the first embodiment, the first fluid return path 91 that allows the motor 1 and the oil chamber 5 to communicate with each other, the inundation detection unit 8 that detects inundation of the oil chamber 5, and the inundation detection unit. 8, a valve member 92 that opens and closes the first fluid return path 91, and a valve member drive mechanism 93 that drives the valve member 92 to open and close the first fluid return path 91 are provided. Thereby, maintenance management of submersible electric pump 200 can be performed easily.

  In the second embodiment, as described above, the fluid pressurization unit 201 that pressurizes the fluid toward the oil chamber 5 is provided between the motor 1 and the oil chamber 5. As a result, pressure can be applied to the fluid that is about to flow into the motor 1 from the oil chamber 5, so that oil rising from the oil chamber 5 can be suppressed. Further, the oil flowing from the oil chamber 5 to the motor 1 side can be effectively returned to the oil chamber 5 by the pressurization by the fluid pressurizing unit 201.

  The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. In the third embodiment, unlike the configuration of the first embodiment in which the valve member driving mechanism 93 is driven to return the fluid under the control of the control unit 10, the valve member driving mechanism is operated by the operation of the operation unit 301 by the user. The structure which drives 93 and returns a fluid is demonstrated.

  As shown in FIG. 6, the submersible electric pump 300 according to the third embodiment includes a motor 1, a rotating shaft 2, an impeller 3, a pump chamber 4, an oil chamber 5, and sliding portions 6a and 6b. A fluid return unit 9 including a mechanical seal 6, an annular body 7, a water immersion detection unit 8, a valve member 92 (see FIG. 2), and a valve member drive mechanism 93 (see FIG. 2) is provided. The submersible electric pump 300 is provided with an operation unit 301. The submersible electric pump 300 is a vertical submersible electric pump in which the rotary shaft 2 extends in the vertical direction.

  The operation unit 301 is configured to receive an operation for opening and closing the valve member 92 by the valve member driving mechanism 93. Specifically, both the operation unit 301 and the valve member driving mechanism 93 have a wireless communication unit (not shown). Further, the operation unit 301 is configured to be able to open and close the first fluid return path 91 by the valve member 92 by driving the valve member driving mechanism 93 by wireless communication. The operation unit 301 can open the first fluid return path 91 even when the motor 1 is driven.

  The remaining configuration of the third embodiment is similar to that of the aforementioned first embodiment.

(Effect of the third embodiment)
In the third embodiment, the following effects can be obtained.

  In the third embodiment, similarly to the first embodiment, the first fluid return path 91 that allows the motor 1 and the oil chamber 5 to communicate with each other, the inundation detection unit 8 that detects inundation of the oil chamber 5, and the inundation detection unit. 8, a valve member 92 that opens and closes the first fluid return path 91, and a valve member drive mechanism 93 that drives the valve member 92 to open and close the first fluid return path 91 are provided. Thereby, maintenance management of submersible electric pump 300 can be performed easily.

  Moreover, in 3rd Embodiment, the operation part 301 which receives the user's operation which opens and closes the valve member 92 by the valve member drive mechanism 93 is provided as mentioned above. Thereby, the valve member 92 can be opened and closed by a user's arbitrary timing by operation of the operation part by a user.

  The remaining effects of the third embodiment are similar to those of the aforementioned first embodiment.

(Modification)
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the third embodiment, the example in which the valve member driving mechanism is driven by the operation of the operation unit by wireless communication is shown, but the present invention is not limited to this. In this invention, you may comprise so that a valve member drive mechanism may be driven by operation of the operation part by wired communication.

  Moreover, in the said 3rd Embodiment, although the operation part and the valve member drive mechanism showed the example comprised so that radio | wireless communication might be performed directly, this invention is not limited to this. In this invention, you may comprise so that an operation part and a valve member drive mechanism may perform wireless communication indirectly. For example, a control unit that can control the valve member drive mechanism may be connected to the submersible electric pump so that the operation unit and the control unit perform wireless communication.

  Moreover, although the example which has arrange | positioned the valve member drive mechanism in the fluid storage part was shown in the said 1st-3rd embodiment, this invention is not limited to this. In the present invention, for example, the valve member drive mechanism may be disposed in the oil chamber.

  Moreover, although the example which has arrange | positioned the valve member in the oil chamber was shown in the said 1st-3rd embodiment, this invention is not limited to this. In the present invention, for example, the valve member may be disposed closer to the motor side (fluid reservoir) than the oil chamber.

  Moreover, although the example which comprised the valve member drive mechanism from the electromagnet, the plate-shaped member, the insulating member, and the spring was shown in the said 1st-3rd embodiment, this invention is not limited to this. In the present invention, for example, the valve member drive mechanism may be constituted by a solenoid valve.

  Moreover, in the said 1st-3rd embodiment, although the example which comprised the water immersion detection part by the electrode type detection part was shown, this invention is not limited to this. In the present invention, for example, the inundation detection unit may be configured by a float type detection unit.

  In the first to third embodiments, an example is shown in which the fluid return path is opened based on the stop of the motor, or the fluid return path is opened based on the operation of the operation unit of the user. The present invention is not limited to this. In this invention, you may comprise so that a fluid return path may be opened based on the detection result of a water immersion detection part, for example. Moreover, you may comprise so that a fluid return path may be opened for every predetermined time at the time of a driving | operation of a motor.

  Moreover, in the said 1st-3rd embodiment, although the example which comprised the fixed part had an electromagnet and the movable part had a permanent magnet was shown, this invention is not limited to this. In this invention, you may comprise so that a fixed part may have a permanent magnet and a movable part may have an electromagnet. Moreover, you may comprise so that both a fixed part and a movable part may have an electromagnet.

  Moreover, in the said 1st-3rd embodiment, although the valve member drive mechanism showed the example comprised so that a fluid return path might be opened and closed with an electromagnet, this invention is not limited to this. In the present invention, for example, the fluid return path may be opened and closed by a gas cylinder.

  Moreover, in the said 2nd Embodiment, although the example provided with the fluid pressurization part 301 containing the groove part 301a inclined with respect to the horizontal surface was shown, this invention is not limited to this. In the present invention, for example, as in the modification shown in FIG. 7, the groove 201 b of the fluid pressurizing unit 201 may be formed in a spiral shape of one or more rounds.

  Moreover, in the said 2nd Embodiment, although the two groove parts were provided in the fluid pressurization part, the present invention is not restricted to this. In the present invention, one groove portion may be provided in the fluid pressurizing portion, or three or more groove portions may be provided.

DESCRIPTION OF SYMBOLS 1 Motor 3 Impeller 4 Pump chamber 5 Oil chamber 6 Mechanical seal 6a, 6b Sliding part 8 Infiltration detection part 14 Fluid storage part 91 1st fluid return path (fluid return path)
92 Valve member 93 Valve member drive mechanism 94 Fixed part 94a, 95a Electromagnet 95 Movable part 100, 200, 300 Submersible electric pump 301 Operation part

Claims (6)

A motor,
A pump chamber in which an impeller driven by the motor is disposed;
An oil chamber provided with a mechanical seal having a sliding portion, and disposed between the motor and the pump chamber;
A fluid return path communicating the motor and the oil chamber;
An inundation detection unit for detecting inundation of the oil chamber;
A valve member provided integrally with the inundation detection unit and opening and closing the fluid return path;
A submersible electric pump comprising: a valve member drive mechanism that drives the valve member to open and close the fluid return path. The submersible electric pump according to claim 1, wherein the valve member driving mechanism includes an electromagnet that drives the valve member. The valve member drive mechanism includes a fixed portion and a movable portion that is moved together with the valve member with respect to the fixed portion,
One of the fixed part and the movable part is provided with the electromagnet, and the other of the fixed part and the movable part is provided with the electromagnet or permanent magnet,
The submersible electric pump according to claim 2, wherein the valve member driving mechanism is configured to open and close the valve member by moving the movable portion relative to the fixed portion.   The submersible electric pump according to any one of claims 1 to 3, wherein the fluid return path is opened by the valve member drive mechanism when the motor is stopped.   The submersible electric pump according to any one of claims 1 to 3, further comprising an operation unit that receives an operation of a user that opens and closes the valve member by the valve member driving mechanism. A fluid reservoir is provided at the lower part inside the motor,
The submersible electric pump according to any one of claims 1 to 5, wherein the valve member driving mechanism is disposed in the fluid reservoir.

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