JP2016167940A - Liquid sealed motor and pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact liquid sealed motor capable of coping with a pressure variation caused by a temperature change of a sealed liquid.SOLUTION: The liquid sealed motor includes a sealed liquid that is sealed. The liquid sealed motor includes: a casing; an absorption mechanism, and a check valve. The casing seals the sealed liquid and is formed so that an external fluid is inhibited from intruding inside. The absorption mechanism absorbs a pressure difference between inside and outside of the casing. The check valve discharges the sealed liquid sealed in the casing toward outside.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a liquid ring motor and a pump device.

  Conventionally, when pumping up deep underground water, pumping is carried out by installing a pump device deep underground. In this case, since a high water pressure is applied to the motor of the pump device, a liquid ring motor that encloses liquid inside the motor is used. In this liquid ring motor, the motor is cooled by a liquid sealed inside (hereinafter also referred to as a sealed liquid), and the bearing of the output shaft is lubricated by the filled liquid.

  In a liquid ring motor, when the motor is driven, the temperature of the sealed liquid rises as the motor generates heat. When the encapsulated liquid expands due to the temperature rise and the internal pressure of the motor increases, the encapsulated liquid tends to flow out from the bearing portion to the outside. As the liquid sealed in the liquid ring motor, for example, antifreeze or oil that is harmless to the human body is used in consideration of flowing out of the motor, but it is preferable that impurities are not mixed in the pumped liquid as much as possible. . Also, if a large amount of sealed liquid is discharged to the outside, when the motor is stopped and the temperature of the sealed liquid drops, the internal pressure of the motor will drop greatly, and there is a risk that a large amount of liquid outside the motor will be mixed into the sealed liquid. is there. For this reason, the liquid ring motor employs an absorption mechanism such as a diaphragm that absorbs the expansion of the sealed liquid to some extent.

JP 59-123439 A

  Such liquid ring motors may be used to pump hot liquids such as hot spring water. In this case, since the sealing liquid is warmed by the external high-temperature liquid, the temperature of the sealing liquid becomes higher than when the low-temperature liquid is pumped. In general, the absorption mechanism such as a diaphragm increases in size according to the volume (pressure) that can be absorbed. Therefore, if the absorption mechanism absorbs the expansion of the sealed liquid in the liquid ring motor, the absorption mechanism becomes large. The liquid ring motor will be enlarged.

  In addition, when using a liquid ring motor to pump hot liquids such as hot spring water, even if a liquid with a high boiling point is used as the sealing liquid, the liquid that has invaded when an external liquid enters the sealing liquid May be heated by the encapsulated liquid and vaporize. When bubbles generated in the casing move to the bearing portion, the bearing cannot be sufficiently lubricated with the filled liquid.

  The present invention has been made in view of at least a part of the above problems, and an object of the present invention is to provide a small liquid ring motor that can cope with a pressure fluctuation caused by a temperature change of the sealed liquid.

  The liquid ring motor of the present invention is a liquid ring motor in which a liquid to be sealed is sealed. The liquid ring motor includes a casing, an absorption mechanism, and a check valve. The casing is formed so as to enclose the encapsulated liquid and to block the outside fluid from entering the inside. The absorption mechanism absorbs a pressure difference between the inside and the outside of the casing. The check valve discharges the sealed liquid sealed in the casing to the outside.

  Such a liquid ring motor includes an absorption mechanism that absorbs the pressure difference between the inside and the outside of the casing, and a check valve that discharges a part of the sealed liquid to the outside. It is possible to prevent the difference from occurring. Further, an absorption mechanism having a small absorption amount can be used, and the liquid ring motor can be downsized. Furthermore, since the casing is formed so as to block external fluid from entering the inside, it is possible to suppress the generation of bubbles in the casing.

Also, a rotor that rotates in the casing, an output shaft that is attached to the rotor and protrudes from a through hole formed in the casing, and a shaft sealing mechanism that is provided in the through hole portion and seals the inside and the outside of the casing And may be further provided. The casing may be formed with a communication hole communicating from the shaft seal mechanism to the outside, and the check valve may be provided in the communication hole.
In this way, when there is a bubble in the vicinity of the bearing, the bubble can be suitably discharged to the outside through the communication hole and the check valve.

Further, the communication hole may be formed such that the end on the outside side is located in the direction in which the output shaft protrudes from the end on the shaft sealing mechanism side.
In this way, when the liquid ring motor is installed so that the output shaft protrudes vertically upward, the air bubbles in the casing can be suitably discharged to the outside.

In addition, the sealing liquid may further include a sealing liquid, and the sealing liquid may have a propylene glycol concentration of 95% by mass or more.
In this way, it is possible to further suppress the generation of bubbles from the sealed liquid when the liquid ring motor is driven.

  Moreover, the secondary conductor formed with the electroconductive material containing aluminum and further attached to the output shaft of a liquid ring motor may be provided, and the secondary conductor may be in direct contact with the sealed liquid sealed in the casing.

  The absorption mechanism absorbs the pressure difference between the inside and the outside of the casing within a range of a first predetermined amount, and the check valve has a pressure inside the casing that is less than the first predetermined amount than the external pressure. A part of the sealing liquid may be discharged to the outside when it becomes larger than the second predetermined amount.

  The stator may further include a stator disposed in a region in contact with the sealing liquid, and the stator may have a winding coated with any of polyethylene, polypropylene, fluororesin, and polyetheretherketone.

  A rotor attached to the output shaft of the liquid ring motor and in contact with the filled liquid; a stator disposed outside the rotor; a can disposed between the rotor and the stator to isolate the rotor from the stator; , May be further provided.

  The liquid ring motor is used to drive a pump that pumps high-temperature liquid, and may be installed in the high-temperature liquid.

A pump device according to the present invention includes a liquid ring motor according to the present invention and a pump attached to an output shaft of the liquid ring motor.
According to such a pump device, the same effect as the liquid ring motor according to the present invention can be obtained.

It is a figure which shows the external appearance of the pump apparatus of this embodiment. It is a figure which shows the cross section of the liquid ring motor of this embodiment. It is a figure which expands and shows the shaft seal mechanism periphery of FIG. It is a figure which shows the non-return valve of this embodiment. It is a time chart which shows the change of the motor internal pressure at the time of operating the liquid ring motor of this embodiment. It is a figure which shows the external appearance of the liquid-sealed motor of a modification.

  Hereinafter, a liquid ring motor and a pump device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an appearance of the pump device according to the present embodiment. As shown in FIG. 1, the pump device 500 includes a liquid ring motor 100 and a submersible pump 200 connected to the liquid ring motor 100.

  The submersible pump 200 has a drive shaft 202 connected to the output shaft 110 of the liquid ring motor 100 and a plurality of blades 204 attached to the drive shaft 202. In the submersible pump 200, the drive shaft 202 and the blades 204 rotate in accordance with the rotational drive of the output shaft 110 of the liquid ring motor 100, thereby pumping up water.

  Next, details of the liquid ring motor of this embodiment will be described. FIG. 2 is a view showing a cross section of the liquid ring motor of the present embodiment. The liquid ring motor 100 is installed in a high-temperature liquid in order to pump a high-temperature liquid such as hot spring water.

  As shown in FIG. 2, the liquid ring motor 100 includes a casing 101. The casing 101 includes a cylindrical frame 102, a first frame side plate 120, and a second frame side plate 130. The liquid ring motor 100 includes a stator (stator) 104 fixed in the frame 102, a rotor (rotor) 107 provided inside the stator 104, and an output shaft 110 attached to the rotor 107. . Further, the liquid ring motor 100 includes a cylindrical can 111 interposed between the stator 104 and the rotor 107.

  Stator 104 has a stator core 105 formed by laminating electromagnetic steel plates, and a stator coil 106 wound around stator core 105. A cable connector 112 for energizing the stator coil 106 is connected to the stator coil 106. The rotor 107 includes a rotor core 108 formed by laminating electromagnetic steel plates, and a secondary conductor 109 that is electrically connected to the rotor core 108. In this embodiment, the rotor core 108 has a slot (not shown) penetrating in the axial direction of the output shaft 110, and a conductive material containing aluminum is inserted into the slot by die casting or the like. Further, the secondary conductor 109 is formed of a conductive material containing aluminum, for example. In the liquid ring motor 100, the rotor 107 rotates within the frame 102 by electromagnetic induction caused by energization of the stator coil 106, and the output shaft 110 also rotates as the rotor 107 rotates.

  The first frame side plate 120 is provided so as to cover an end portion on the side to which the submersible pump 200 is not connected (end portion on the anti-load side). Specifically, the first frame side plate 120 is fixed to the anti-load side bracket 122 by bolts 184. On the other hand, the second frame side plate 130 is provided so as to cover the end (load side end) on the side to which the submersible pump 200 is connected. Specifically, the second frame side plate 130 is fixed to the load side bracket 131 by bolts 194.

  The can 111 separates the outer stator chamber where the stator 104 is disposed from the inner rotor chamber where the rotor 107 is disposed. An insulating cooling oil 115 is enclosed in the stator chamber in order to cool the heat generated from the stator 104 and the like. The rotor chamber is filled with a sealing liquid 114 in order to cool the heat generated from the rotor 107 and the like and improve the slidability of the output shaft 110. The can 111 isolates the stator chamber and the rotor chamber so that the cooling liquid 114 and the cooling oil 115 are not mixed with each other. As described above, the stator chamber and the rotor chamber are separated from each other by the can 111, so that the stator 104 can be cooled by the insulating cooling oil 115 without coating the stator coil 106. Further, the cooling oil 115 can be prevented from being discharged to the outside of the liquid ring motor 100.

  In this embodiment, paraffin oil that is insulating oil is used as the cooling oil 115, and propylene glycol that is antifreeze is used as the cooling liquid 114. The cooling liquid 114 sealed in the rotor chamber preferably uses propylene glycol substantially free of impurities, and specifically, it is preferable to seal 95% by mass or more of propylene glycol. Propylene glycol, which contains almost no impurities, has a boiling point of 160 ° C. or higher. Therefore, when the liquid ring motor 100 is installed and operated in high-temperature groundwater such as hot spring water, the sealed liquid 114 in the rotor chamber is vaporized. Can be suppressed.

  A diaphragm (pressure fluctuation absorbing mechanism) 182 that absorbs pressure fluctuations in the rotor chamber is provided on the anti-load side of the liquid ring motor 100. The diaphragm 182 absorbs the pressure fluctuation between the rotor chamber and the external pressure of the liquid ring motor 100 by displacing the film in accordance with the pressure fluctuation in the rotor chamber. The diaphragm 182 has a predetermined value in consideration of the rating of the liquid ring motor 100, the depth and temperature of ground water in which the liquid ring motor 100 is installed (for example, 50 ° C. to 90 ° C.), the margin, and the like. What can absorb the volume (pressure difference) may be used.

  On the non-load side of the liquid ring motor 100, a radial bearing 188 and a thrust bearing 190 for supporting the output shaft 110 are provided. On the other hand, on the load side of the liquid ring motor 100, an O-ring 196 that seals between the second frame side plate 130 and the load side bracket 131, and a radial bearing 198 for supporting the output shaft 110 are provided. ing.

  A through hole 132 through which the output shaft 110 can pass is formed in the center portion of the second frame side plate 130 so that the tip of the output shaft 110 protrudes to the outside of the liquid ring motor 100. The output shaft 110 projects to the outside of the liquid ring motor 100 through the through hole 132 and is connected to the drive shaft 202 of the submersible pump 200.

  The through-hole 132 is provided with a shaft seal mechanism 150 that prevents the sealed liquid 114 from leaking to the outside and water outside the liquid seal motor 100 from entering the liquid seal motor 100. Yes. FIG. 3 is an enlarged view showing the periphery of the shaft sealing mechanism 150 of FIG. The shaft sealing mechanism 150 includes a mechanical seal 152 and a sand slinger 154.

  The mechanical seal 152 has a rotating ring 152a fixed to the output shaft 110 and a fixed attached to the load side bracket 131 in order to seal the sealed liquid 114 and water outside the liquid ring motor 100 from each other. A sliding surface 152c is formed between the ring 152b. The sand slinger 154 is provided so as to cover the upper part of the mechanical seal 152 and prevents foreign matters such as sand from entering the liquid ring motor 100. As the mechanical seal 152, a known seal having a synthetic rubber such as nitrile rubber and a metal ring can be used. The shaft seal mechanism 150 may include, for example, a mechanical seal that seals leakage of the sealing liquid 114 to the outside and a mechanical seal that seals external water or the like from entering the rotor chamber.

The liquid ring motor 100 includes a check valve 160 (see the broken line in FIG. 2 and FIG. 3).
. The check valve 160 is provided so that the sealed liquid 114 can be discharged from the vicinity of the shaft seal mechanism 150 to the upper part of the liquid seal motor 100. In the present embodiment, a communication hole 158 for attaching the check valve 160 is formed in the load side bracket 131. The communication hole 158 is formed so as to communicate from the shaft seal mechanism 150 toward the outside of the liquid seal motor 100. In other words, the communication hole 158 communicates the region adjacent to the shaft seal mechanism 150 and the outside of the liquid seal motor 100. Specifically, the communication hole 158 communicates the outer peripheral surface of the load side bracket 131 (the outer peripheral surface viewed from the output shaft 110) and the rotor chamber. In addition, the communication hole 158 is positioned in the direction Xm in which the output shaft 110 protrudes from the end 158a (for example, the center of the end 158a) on the outer side of the outer end 158b (for example, the center of the end 158b). It is formed as follows. That is, the communication hole 158 is formed so as to face vertically upward (inclined with respect to the horizontal direction) when the liquid ring motor 100 is installed. The check valve 160 is attached to the communication hole 158.

  FIG. 4 is a view showing the check valve of the present embodiment. The check valve 160 includes a check valve frame 161, a valve body 165, a spring 166, and a filter 167. The check valve frame 161 holds a valve body 165, a spring 166, and a filter 167. The check valve frame 161 is formed with a flow hole 162 for flowing the sealing liquid 114. The flow hole 162 is formed so that the hole diameter of the end 162 a on the inner side of the liquid ring motor 100 is narrow. The valve body 165 is disposed in the flow hole 162 and is urged by the spring 166 toward the inner end portion 162 a of the check valve frame 161. The valve body 165 is made of, for example, resin. The valve body 165 seals the sealed liquid 141 so that it cannot pass through the flow hole 162 when it comes into contact with the end 162 a by the urging force of the spring 166. The filter 167 is provided to prevent foreign matter outside the liquid ring motor 100 from entering the check valve 160 and the liquid ring motor 100, and a known liquid filter can be used.

  In the check valve 160, the valve body 165 moves outward against the biasing force of the spring 166 when the pressure of the filled liquid 114 in the rotor chamber becomes a predetermined amount or more larger than the external pressure of the liquid ring motor 100. The sealed liquid 114 in the rotor chamber is discharged to the outside. That is, the check valve 160 discharges the sealed liquid 114 to the outside according to the pressure difference between the rotor chamber and the external pressure. Here, the pressure difference at which the valve body 165 of the check valve 160 moves is made smaller than the volume (pressure difference) that can be absorbed by the diaphragm 182. For example, the check valve 160 only needs to determine the biasing force of the spring 166 in consideration of a margin for the volume (pressure difference) that can be absorbed by the diaphragm 182.

  FIG. 5 is a time chart showing changes in the motor internal pressure (rotor indoor pressure) when the liquid ring motor of the present embodiment is operated. In FIG. 5, the alternate long and short dash line indicates a comparative example that includes the diaphragm 182 but does not include the check valve 160. FIG. 5 shows an example in which the sealed liquid 114 is initially sealed in the rotor chamber at an initial set pressure P1 (for example, atmospheric pressure) at room temperature (for example, 20 ° C.) (time t0).

  When the liquid ring motor 100 is installed in high temperature (for example, 80 ° C.) groundwater (time t1), the filled liquid 114 inside the motor is warmed by the high temperature groundwater. For example, when 95% by mass of propylene glycol is used as the encapsulating liquid 114, when the temperature of the encapsulating liquid 114 increases from 20 ° C. to 80 ° C., the volume increases by several percent. Thus, the motor internal pressure Pm rises while a part of the fluctuation is absorbed by the diaphragm 182 (time t1 to t2).

  In general, when pumping a liquid having a relatively low temperature (for example, about 20 ° C.), the temperature of the sealed liquid 114 does not rise to about 80 ° C. even if the underwater motor is operated. For this reason, the volume of the sealed liquid 114 of the liquid ring motor 100 placed in high-temperature groundwater is greatly increased as compared with the case of pumping a liquid at about 20 ° C. When the volume (pressure) fluctuation is absorbed only by the diaphragm 182, the diaphragm 182 increases in size because the larger the volume (pressure) fluctuation that can be absorbed, the larger the diaphragm size.

  On the other hand, the liquid ring motor 100 of this embodiment includes a check valve 160. Accordingly, when the motor internal pressure Pm becomes larger than a predetermined amount (for example, Pa) with respect to the external pressure (time t2), the check valve 160 is opened and the sealed liquid 114 is discharged to the outside, and the motor internal pressure Pm is constant pressure P2. It will not be larger than (= P1 + Pa). With this configuration, it is possible to suppress an excessive increase in the motor internal pressure Pm without using the diaphragm 182 having a large absorption amount.

  When the liquid ring motor 100 is driven in a state where the liquid ring motor 100 is installed in high-temperature groundwater, the temperature of the sealed liquid 114 further increases due to heat generated by driving the liquid ring motor 100. For this reason, in the motor of the comparative example indicated by the one-dot chain line, the motor internal pressure Pm further increases (time t3 to t4). On the other hand, in the liquid ring motor 100 of the present embodiment shown by the solid line, since the sealed liquid 140 is discharged from the check valve 160 to the outside, the motor internal pressure Pm does not become larger than the pressure P2.

  Next, when the driving of the liquid ring motor 100 is stopped, the heat generated by the driving of the liquid ring motor 100 is eliminated, so that the temperature of the sealing liquid 114 is lowered to the same temperature as the external ground water (for example, 80 ° C.). At this time, the motor internal pressure Pm decreases by the amount of the sealing liquid 114 released with the heat generation of the liquid ring motor 100 (time t4 to t5). However, since the decrease in the motor internal pressure Pm is offset by the pressure Pa absorbed by the diaphragm 182, the motor internal pressure Pm does not become an excessive negative pressure (time t5, pressure P5). Then, when the liquid ring motor 100 is driven again, the motor internal pressure Pm again changes within the range of the pressures P5 to P2.

  Since the liquid ring motor 100 of the present embodiment described above includes the diaphragm 182 and the check valve 160, the internal pressure and the external pressure of the liquid ring motor 100 can be increased even when pumping high-temperature liquid such as hot spring water. An increase in the difference can be suppressed. Further, a smaller diaphragm can be used as compared with an underwater motor having only the diaphragm 182, and the liquid ring motor 100 can be downsized. Further, the casing 101 does not include a valve for guiding fluid from the outside to the inside, and is formed so as to block the outside fluid from entering the inside, thereby suppressing the generation of bubbles in the rotor chamber. can do.

  Moreover, in the present embodiment, a communication hole 158 is formed in the load side bracket 131 from the shaft seal mechanism 150 to the outside, and a check valve 160 is provided in the communication hole 158. In general, in submersible motors, even if the liquid tightness in the rotor chamber is sufficiently secured, for example, gas remains in the gap formed during rotor manufacture, bubbles are generated during driving due to cavitation, etc. It is conceivable that air bubbles enter from. When such bubbles move to the shaft sealing mechanism 150, the shaft sealing mechanism 150 is not sufficiently lubricated. In particular, when the output shaft 110 is installed so as to face vertically upward as in the liquid ring motor 100 of the present embodiment, it is considered that bubbles generated in the rotor chamber easily move to the upper shaft sealing mechanism 150. It is done. On the other hand, by providing the check valve 160 in the communication hole 158 formed outward from the shaft seal mechanism 150, the bubbles near the shaft seal mechanism 150 are discharged to the outside along with the discharge of the sealing liquid 114. Can do.

  Further, the communication hole 158 in which the check valve 160 is provided is formed such that the end 158b on the outer side is positioned in the direction Xm in which the output shaft 110 protrudes from the end 158a on the rotor chamber side. That is, the communication hole 158 is formed so as to face vertically upward (inclined with respect to the horizontal direction) when the liquid ring motor 100 is installed. Accordingly, when bubbles are generated in the rotor chamber, the bubbles can be guided to the outside, and the bubbles in the vicinity of the shaft seal mechanism 150 can be discharged to the outside.

In addition, since the check valve 160 is provided on the outer peripheral surface of the load side bracket 131, the check valve 160 suppresses intrusion of foreign matters such as sand as compared with the valve provided on the upper surface of the liquid ring motor 100. be able to. Furthermore, since the check valve 160 includes the filter 167, it is possible to more reliably prevent foreign matter from entering.

  In this embodiment, 95 mass% or more of propylene glycol is used for the sealing liquid 114 that lubricates the shaft seal mechanism 150. Propylene glycol is harmless to the human body, has a very low freezing point, and a very high boiling point. For this reason, it is possible to prevent the groundwater to be pumped from being unusable, and it can be used even in a cold region, and it is possible to suppress the sealing liquid 114 from boiling and being vaporized.

  Moreover, since propylene glycol is highly water-soluble, even if outside water enters the rotor chamber unintentionally, the intruding water mixes with the sealing liquid 114. For this reason, it can suppress that the water which penetrate | invaded boiled and a bubble arises inside. Furthermore, when propylene glycol contains almost no impurities, bubbles such as hydrogen gas are not generated in the rotor chamber, so that it is not necessary to perform protective treatment such as painting on the rotor.

  In the liquid ring motor 100 of the above-described embodiment, a so-called canned motor in which the rotor 107 provided on the output shaft 110 and the stator 104 provided on the outer periphery of the rotor 107 are separated by a cylindrical can 111. Although described, it is not limited to this example. For example, as shown in the liquid ring motor 300 of the modification of FIG. 6, the rotor 107 and the stator 104 may not be isolated without the can 111. In FIG. 6, the same components as those in FIG. 1 are denoted by the same reference numerals. In this case, the sealed liquid 314 that is sealed inside the liquid seal motor 100 and lubricates the shaft seal mechanism 150 comes into contact with the rotor 107 and the stator 104, respectively. In this case, as the sealing liquid 314, an insulating oil such as paraffin oil may be used, or an antifreeze liquid such as propylene glycol may be used.

  In the liquid-sealed motor 300 according to the modification, when an antifreeze liquid is used as the sealing liquid 314, it is preferable to use propylene glycol having a concentration of 95% by mass or more as in the case of the sealing liquid 114 of the embodiment. Further, when an antifreeze liquid is used as the sealing liquid 314, the stator coil 106 may be protected for insulation. As an example, the stator coil 106 is preferably coated with one of polyethylene, polypropylene, fluororesin, and polyetheretherketone (PEEK). In particular, when the temperature of the sealing liquid 314 is expected to be higher than 100 ° C., it is preferable to use a fluororesin or a polyether ether ketone.

  In order to ensure the insulation of the stator 104, a stator coil 106 previously coated with a nonconductive material may be wound around the stator core 105. Moreover, you may coat all the outer surfaces of the part which contacts the sealing liquid 314 among the stators 104 with a nonelectroconductive thermoplastic resin. In this case, the stator 104 may be coated by a method of immersing the stator 104 in a molten non-conductive thermoplastic resin and forming a film of the thermoplastic resin on the outer surface of the stator 104.

  In the above embodiment, the diaphragm 182 that absorbs the motor internal pressure is provided. However, for example, any bellows that is capable of absorbing fluctuations in the motor internal pressure, such as a bellows that is displaced according to a change in the motor internal pressure, may be used. Good.

In the above-described embodiment, the check valve 160 is provided in the communication hole 158 communicating from the shaft sealing mechanism 150 toward the outside, and discharges the sealed liquid 114 toward the upper outside. However, the check valve 160 is limited to this example. Not. The check valve 160 may be provided at any place such as attached to the lower part of the liquid ring motor 100 or 300. In addition, the direction of the sealing liquid 114 can be arbitrarily determined, for example, by discharging the sealing liquid 114 downward to the outside. Further, the check valve 160 is not limited to the one attached to the outer peripheral surface of the load side bracket 131, and may be attached to the upper surface of the load side bracket 131. Further, instead of the load side bracket 131, the second frame side plate 130 may be provided. Further, the check valve 160 is not limited to the one attached to the load side bracket 131 or the second frame side plate 130, and may be configured integrally therewith.

  In the above embodiment, the check valve 160 includes the check valve frame 161, the valve body 165, the spring 166, and the filter 167. However, as long as the internal pressure of the motor becomes larger than a predetermined amount with respect to the external pressure, any liquid may be used as long as the liquid is discharged to the outside and the external liquid is not allowed to enter the liquid 114. For example, the check valve 160 may not have the filter 167.

  In the above embodiment, the liquid ring motors 100 and 300 are installed so that the output shaft 110 protrudes vertically upward. However, the present invention is not limited to this example, and may be installed and used sideways. Good.

  Although the embodiments of the present invention have been described above, the above-described embodiments of the present invention are for facilitating the understanding of the present invention and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof. In addition, any combination of the embodiment and the modified example is possible within a range where at least a part of the above-described problems can be solved or a range where at least a part of the effect can be achieved, and is described in the claims and the specification. Any combination or omission of each component is possible.

100 Liquid-sealed motor 101 Casing 102 Frame 104 Stator 106 Stator coil 107 Rotor 109 Secondary conductor 110 Output shaft 114 Filled liquid 120 First frame side plate 122 Anti-load side bracket 130 Second frame side plate 131 Load side bracket 132 Through hole 150 Shaft seal mechanism 152 Mechanical seal 152a Rotating ring 152b Fixed ring 152c Sliding surface 154 Sand slinger 158 Communication hole 160 Check valve 200 Submersible pump 300 Liquid ring motor 500 Pump device

Claims (10)

A liquid ring motor in which an encapsulated liquid is enclosed,
A casing formed so as to enclose the encapsulated liquid and to block external fluid from entering the interior;
An absorption mechanism for absorbing the pressure difference between the inside and the outside of the casing;
A check valve that discharges the sealed liquid sealed in the casing to the outside;
A liquid ring motor. The liquid ring motor according to claim 1,
A rotor rotating within the casing;
An output shaft attached to the rotor and projecting from a through hole formed in the casing;
A shaft sealing mechanism that is provided in the through-hole portion and seals the inside and the outside of the casing;
Further comprising
In the casing, a communication hole communicating from the shaft sealing mechanism toward the outside is formed,
The check valve is provided in the communication hole.
Liquid ring motor. The liquid ring motor according to claim 2,
The communication hole is formed such that an end on the outer side is positioned in a direction in which the output shaft protrudes from an end on the shaft sealing mechanism side.
Liquid ring motor. A liquid ring motor according to any one of claims 1 to 3,
Further comprising a sealing liquid sealed in the casing;
The sealing liquid has a propylene glycol concentration of 95% by mass or more.
Liquid ring motor. A liquid ring motor according to any one of claims 1 to 4,
A secondary conductor formed of a conductive material containing aluminum and attached to the output shaft of the liquid ring motor;
The secondary conductor is in direct contact with the sealing liquid sealed in the casing;
Liquid ring motor. A liquid ring motor according to any one of claims 1 to 5,
The absorption mechanism absorbs a pressure difference between the inside and the outside of the casing within a first predetermined amount range,
The check valve discharges a part of the sealed liquid to the outside when the pressure inside the casing exceeds a second predetermined amount smaller than the first predetermined amount than the external pressure. ,
Liquid ring motor. The liquid ring motor according to any one of claims 1 to 6,
A stator disposed in a region where the sealing liquid comes into contact;
The stator has windings coated with any of polyethylene, polypropylene, fluororesin, polyetheretherketone,
Liquid ring motor. A liquid ring motor according to any one of claims 1 to 7,
A rotor attached to the output shaft of the liquid ring motor and in contact with the sealed liquid;
A stator disposed outside the rotor;
A can that is disposed between the rotor and the stator and that separates the rotor and the stator;
A liquid ring motor further comprising: A liquid ring motor according to any one of claims 1 to 8,
Used to drive a pump that pumps hot liquid and installed in the hot liquid;
Liquid ring motor. The liquid ring motor according to any one of claims 1 to 9,
A pump attached to the output shaft of the liquid ring motor;
A pump device comprising:

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