JP5567418B2 - Underwater rotating equipment - Google Patents

Description

  The present invention relates to a submersible rotating device such as a submersible pump used for water supply or drainage or a submerged mixer that stirs water in a water tank, and more specifically, an electric motor that rotationally drives an impeller connected to an output shaft is accommodated. A first shaft sealing mechanism provided on the impeller side of the output shaft, and a shaft sealing chamber provided between the motor chamber and the impeller. The present invention relates to an underwater rotating device that is shaft-sealed by a second shaft-sealing mechanism provided on the electric motor chamber side.

  As shown in FIG. 9, a vertical shaft submersible pump 80 as an example of a submersible rotating device includes an electric motor chamber 82 in which an electric motor 81 that rotates and drives an impeller 87 connected to an output shaft 86, an electric motor chamber 82, A shaft sealing chamber 84 provided between the impeller 87, a pump casing 83 having the shaft sealing chamber 84 and a discharge port 89, a suction bell 85 having a suction port 88 in the lower portion and accommodating the impeller 87, and the like. The water is sucked from the suction port 88 and discharged from the discharge port 89 by the rotation of the impeller 87.

  The shaft seal chamber 84 is shaft-sealed by a mechanical seal 91 provided on the impeller 87 side of the output shaft 86 and a mechanical seal 92 provided on the motor chamber 82 side, and lubricating oil is contained in the shaft seal chamber 84. It is enclosed. The sliding surface of the mechanical seal 91 is not lubricated and cooled by the water in the pump casing 83, and the sliding surface of the mechanical seal 92 is lubricated and cooled by the lubricating oil sealed in the shaft sealing chamber 84.

  In Patent Document 1, as shown in FIG. 1 in Patent Document 1, an electric motor casing 1 in which an electric motor having an output shaft 3 arranged in a vertical direction is accommodated, and an electric motor casing 1 positioned on the output shaft 3 and below the electric motor. Are provided between the hydraulic pressure part 2 and the motor casing 1 and the hydraulic pressure part 2, surround the output shaft 3, and both the hydraulic pressure part 2 and the motor casing 1 through mechanical seals 5 and 6. A submersible pump with an intermediate chamber 4 sealed from is disclosed. In addition, the code | symbol of each structure respond | corresponds to the description of patent document 1. FIG.

  The intermediate chamber 4 is divided into an inner annular chamber 8 and an outer annular chamber 9 by a dividing wall 7, and the inner annular chamber 8 and the outer annular chamber 9 are communicated by an overflow pipe 22. The internal annular chamber 8 is preliminarily filled with a predetermined amount of lubricating oil, and is configured to lubricate and cool the mechanical seals 5 and 6.

  In Patent Document 2, as shown in FIG. 1 in Patent Document 2, an electric motor chamber 9 in which an electric motor that rotationally drives an impeller 6 connected to an output shaft 7 is housed, an electric motor chamber 9, an impeller 6, A shaft seal chamber 4 provided between the pump chamber 8 and the pump chamber 8 for accommodating the impeller 6 and the like. From the gas supply device 1 provided outside, the motor chamber 9 or the shaft seal chamber 4 is connected to the hose and the pipe 2, A submersible pump is disclosed that is configured so that gas is constantly supplied little by little through the hose connector 3. In addition, the code | symbol of each structure respond | corresponds to the description of patent document 2. FIG.

Japanese National Patent Publication No. 3-504150 Japanese Patent Laying-Open No. 2005-2777

  In the submersible pump 80 in which the lubricating oil is sealed in the shaft sealing chamber 84 as shown in FIG. 9, the lubricating oil gradually deteriorates due to the deterioration of the lubricating oil over time or the water leaked from the mechanical seal 91 into the shaft sealing chamber 84. Therefore, it is necessary to change the lubricating oil periodically.

  If the injection amount of the lubricating oil is too large, the internal pressure of the shaft seal chamber 84 may increase and the mechanical seals 91 and 92 may be damaged. If the amount is too small, the mechanical seal 92 may be seized or the life may be shortened. Need to be injected. In addition, it is necessary to dispose of the discharged lubricating oil so as not to cause environmental pollution, and the replacement operation of the lubricating oil itself is very complicated.

  Further, in the submersible pump 80, when the mechanical seal 91 is broken, the lubricating oil sealed in the shaft sealing chamber 84 may leak to the outside and contaminate the environment.

  Further, in order to inject and discharge the lubricating oil, an injection passage 93 and a discharge passage 94 for communicating the outer surface of the peripheral wall portion of the pump casing 83 and the shaft sealing chamber 84, and an air passage 95 for extracting air in the shaft sealing chamber 84. Therefore, the structure is complicated.

  Similar to the above-described submersible pump 80, the submersible pump described in Patent Document 1 is expected to have a problem that the replacement work of the lubricating oil is complicated and a problem that the lubricating oil may leak to the outside and contaminate the environment. The

  The submersible pump described in Patent Document 2 maintains a pressure of an airtight portion such as the electric motor chamber 9 and the shaft seal chamber 4 higher than the outside by the gas supplied from the gas supply device 1, so that Even if it does not use the shaft seal mechanism and the lubricating oil of the shaft seal mechanism, water can be prevented from entering the motor chamber 9 and the shaft seal chamber 4.

  However, since it is necessary to arrange a hose and a pipe 2 from the gas supply device 1 installed on the ground to the submersible pump, there is a problem that the equipment cost is excessive. Moreover, since the hose and the pipe 2 are disposed in water, there is a possibility that the hose and the pipe 2 may be damaged due to a water flow or a collision of foreign matter in the water.

  When the gas supply device 1 is cooled in the electric motor chamber 9 or the shaft seal chamber 4 at a pressure higher than the maximum water depth of the pump and the pump warmed during operation is cooled after being stopped, Since it is necessary to inject an amount of gas that exceeds the rate at which the gas in the motor chamber 9 contracts, a large compressor is required in accordance with the depth of water in which the submersible pump is installed, and there is a problem that equipment costs and operating costs increase. there were.

  Note that Patent Document 2 describes that an oil seal or the like may be provided in order to maintain airtightness for a short time, but in order to constantly pressurize the motor chamber 9 or the shaft seal chamber 4 with gas, A thin film of water or oil necessary for lubrication such as an oil seal could not be obtained, and there was a problem of heat generation and wear of the sliding part.

  In view of the above-described problems, an object of the present invention is to provide an inexpensive underwater rotating device that does not require lubricating oil for a shaft seal mechanism.

In order to achieve the above object, the first characteristic configuration of the underwater rotating device according to the present invention includes an electric motor that rotationally drives an impeller coupled to an output shaft, as described in claim 1 of the claims. A first shaft sealing mechanism provided on the impeller side of the output shaft, and a shaft sealing chamber provided between the motor chamber and the impeller. with the shaft seal by the second shaft seal mechanism provided in the electric motor chamber side, the lubricating oil is a rotating device in the water which is not sealed in the shaft sealing chamber, the shaft seal chamber, the first A heat exchange mechanism that promotes dew condensation of the steam that has entered the shaft sealing chamber from the first shaft sealing mechanism so as to function as a saturated steam chamber that condenses the steam that has entered the shaft sealing chamber from the shaft sealing mechanism. It is in the point comprised for the sealed room .

According to the above-described configuration, the shaft sealing chamber functions as a saturated steam chamber that condenses the vapor that has entered the shaft sealing chamber from the first shaft sealing mechanism, so that the steam that has entered the shaft sealing chamber from the first shaft sealing mechanism Condensation occurs in the shaft seal chamber. Therefore, it is possible to reduce the possibility that the vapor that has entered the shaft sealing chamber enters the motor chamber via the second shaft sealing mechanism, corrodes the bearing, and deteriorates the insulation of the motor . Since the heat exchange mechanism promotes condensation of the steam that has entered the shaft seal chamber from the first shaft seal mechanism, it is possible to further reduce the risk that the steam that has entered the shaft seal chamber will enter the motor chamber. Na us, together with condensation water can be used to cool the lubrication of the first shaft seal mechanism, through the first shaft seal mechanism to capture vapors coming penetrated into shaft seal chamber, the steam is second axis The possibility of entering the electric motor room through the sealing mechanism can be reduced.

  Even if the first shaft sealing mechanism is damaged and water enters the shaft sealing chamber, the second shaft sealing mechanism can prevent water from entering the motor chamber, so that the electric motor leaks. Such a fear can be reduced.

  The first shaft sealing mechanism is preferably a mechanical seal, and lubrication and cooling are performed with ambient water. As the second shaft sealing mechanism, a shaft sealing mechanism that does not require lubrication and cooling with a lubricating oil, for example, a non-water-filled mechanical seal, an oil seal, a V ring, an end face sliding rubber seal, or the like is preferably used.

  The shaft sealing chamber is sealed by a first shaft sealing mechanism provided on the impeller side of the output shaft and a second shaft sealing mechanism provided on the motor chamber side, and the second shaft sealing mechanism requires lubricating oil. This eliminates the need for periodic replacement work of the lubricant and disposal of the replaced lubricant. Furthermore, for example, even if the first shaft sealing mechanism is broken, there is no possibility that the lubricating oil leaks into water and pollutes the environment. Further, since no lubricating oil is required, it is not necessary to form a lubricating oil injection passage, a discharge passage and an air passage communicating with the shaft seal chamber, so that the structure can be simplified.

  As the submersible rotating device, a submersible pump such as an axial flow pump, a mixed flow pump, and a vortex pump, and a submersible mixer are preferable applications.

In the second feature configuration, as described in claim 2, in addition to the first feature configuration described above, the outer surface of the peripheral wall portion of the shaft sealing chamber is in contact with the flow path of the water discharged from the impeller. It is in the point which is comprised.

According to the above-described configuration, the outer surface of the peripheral wall portion of the shaft seal chamber is cooled by the water discharged from the impeller, so that the dew condensation of the infiltrated steam is further promoted by the heat exchange mechanism provided in the shaft seal chamber.

In the third characteristic configuration, as described in the third aspect, in addition to the first or second characteristic configuration described above , the heat exchange mechanism is directed from the inner surface of the peripheral wall portion of the shaft sealing chamber toward the output shaft. It is formed of a single or a plurality of heat radiating plates that are formed so as to condense on the surface the vapor that has entered the shaft sealing chamber from the first shaft sealing mechanism.

  According to the above-described configuration, the heat exchange mechanism is configured by a single or a plurality of heat radiating plates formed extending from the inner surface of the peripheral wall portion of the shaft sealing chamber toward the output shaft. Therefore, the vapor is likely to come into contact with the heat radiating plate, and condensation is more likely to occur. From the viewpoint of heat conduction, it is preferable that the heat radiating plate is integrally formed with the peripheral wall portion of the shaft sealing chamber.

In the fourth feature configuration, as described in claim 4, in addition to the first or second feature configuration described above , the heat exchanging mechanism is configured to be radial from the axis of the output shaft. A point that is formed to extend from the inner surface of the peripheral wall portion of the shaft seal chamber toward the output shaft, and is configured by a plurality of heat radiating plates that condense on the surface the vapor that has entered the shaft seal chamber from the first shaft seal mechanism. It is in.

  According to the above-described configuration, the heat exchange mechanism is configured by a plurality of heat radiating plates formed to extend from the inner surface of the peripheral wall portion of the shaft sealing chamber toward the output shaft so as to be radial from the shaft core of the output shaft. Therefore, the surface area of the heat exchange mechanism is increased, and the vapor easily comes into contact with the heat radiating plate, so that it is more likely to condense. From the viewpoint of heat conduction, it is preferable that the heat radiating plate is integrally formed with the peripheral wall portion of the shaft sealing chamber.

  In the fifth feature configuration, as described in claim 5, in addition to the fourth feature configuration described above, the surfaces of the plurality of heat radiating plates face each other along the axial direction of the output shaft. It is in the point where it is arranged.

  According to the above-described configuration, the surfaces of the plurality of heat radiating plates are arranged so as to face each other along the axial direction of the output shaft, so that the steam that has entered the shaft sealing chamber from the first shaft sealing mechanism radiates heat. It moves to the 2nd shaft seal mechanism side along the surface of a board. Since the contact time with the heat radiating plate until the steam moves from the first shaft sealing mechanism side to the second shaft sealing mechanism side becomes longer, condensation tends to occur.

  In the sixth feature configuration, as described in claim 6, in addition to the fourth feature configuration described above, the surfaces of the plurality of heat radiating plates extend along the direction intersecting the axial direction of the output shaft. It exists in the point arrange | positioned so that it may oppose.

  According to the above-described configuration, since the surfaces of the plurality of heat sinks are arranged so as to face each other along the direction intersecting the axial direction of the output shaft, the first heat seal mechanism has entered the shaft seal chamber. The steam is prevented from moving to the second shaft seal mechanism side on the electric motor chamber side and is likely to condense by contacting the heat sink.

  In the seventh feature configuration, in addition to any of the third to sixth feature configurations described above, the shaft sealing chamber is openable and closable for draining condensed water to the outside. A drain mechanism is provided, and the heat radiating plate is provided with an inclined surface that is inclined toward the drain mechanism so as to be a guide plate that guides dew condensation water on the surface thereof toward the drain mechanism.

  According to the above-described configuration, the dew condensation water on the surface of the heat radiating plate is guided to the drain mechanism along the inclined surface that is inclined toward the drain mechanism so as to be a guide plate that is guided toward the drain mechanism. The condensed water accumulated in the shaft seal chamber can be drained from the drain mechanism to the outside without disassembling the shaft seal chamber.

  In the eighth feature configuration, as described in claim 8, in addition to the seventh feature configuration described above, the drain mechanism is provided with a check valve and a gas for supplying pressurizing gas to the shaft seal chamber A supply mechanism is provided, and the condensed water stored in the shaft sealing chamber by the gas supply mechanism is drained through the check valve.

  According to the above-described configuration, the shaft sealing chamber is pressurized with the pressurizing gas supplied by the gas supply mechanism, the check valve provided in the drain mechanism is opened, and the condensed water stored in the shaft sealing chamber is surely drained. Can do. Furthermore, for example, by supplying pressurized gas to the shaft seal chamber by a hose or piping from a gas supply mechanism installed on the ground, the condensed water stored in the shaft seal chamber is drained while the underwater rotating device is submerged. You can also.

  In the ninth feature configuration, in addition to any of the first to eighth feature configurations described above, in addition to the above-described first to eighth feature configurations, the condensed water has reached a predetermined amount in the shaft seal chamber. It is in the point provided with the water level sensor to detect.

  According to the above configuration, since the shaft seal chamber is equipped with the water level sensor, the condensed water accumulated in the shaft seal chamber reaches a predetermined amount without the operator checking the submersible rotating device to the ground. I understand that. In addition, if the dew condensation water is stored at a faster pace than the previously assumed pace, it can be seen that the first shaft sealing mechanism is broken and water has entered the shaft sealing chamber. The water level sensor is preferably a float type or an electrode type.

  In the tenth feature configuration, in addition to any one of the first to ninth feature configurations described above, the output shaft is installed in a vertical posture, and the first shaft sealing mechanism In the bottom surface of the shaft sealing chamber, a recess is formed around the output shaft so that the dew condensation water comes into contact therewith.

  According to the above-described configuration, since the concave portion is formed around the output shaft in the bottom surface of the shaft sealing chamber, the condensed water accumulates in the concave portion and comes into contact with the first shaft sealing mechanism to lubricate and cool the first shaft sealing mechanism. In addition, the steam entering the shaft sealing chamber via the first shaft sealing mechanism can be captured, and the risk of the vapor entering the motor chamber via the second shaft sealing mechanism can be reduced.

  According to the eleventh feature configuration, as described in claim 11, in addition to any one of the first to tenth feature configurations described above, the output shaft is installed in a vertical posture, and condensed water is output from the output. The water storage wall is provided around the output shaft so as to be stored along the shaft.

  According to the above-described configuration, since the water storage wall is provided around the output shaft, the condensed water accumulates in the water storage wall and comes into contact with the first shaft sealing mechanism to assist lubrication and cooling of the first shaft sealing mechanism, and The vapor entering the shaft sealing chamber via the single shaft sealing mechanism can be captured, and the risk of the vapor entering the motor chamber via the second shaft sealing mechanism can be reduced.

The twelfth characterizing feature is, as described in the claim 12, in addition to any characteristic feature of the first or al eleventh described above, the shaft sealing chamber, with the rotation of the output shaft The rotating blade is provided, and the steam that has entered the shaft-sealed chamber from the first shaft sealing mechanism is guided to the heat exchange mechanism by the stirring blade.

  According to the above-described configuration, since the air flow is generated in the shaft seal chamber by the rotation of the stirring blade and the steam that has entered the shaft seal chamber from the first shaft seal mechanism is guided to the heat exchange mechanism, the shaft seal chamber The invaded steam is guided by the heat exchange mechanism on the air stream and condensed. In addition, the heat exchange mechanism is cooled by the airflow itself generated by the stirring blades, and the steam comes into contact with the cooled heat exchange mechanism, so that condensation is more likely to occur. Since the stirring blade rotates with the rotation of the output shaft, there is no need to newly provide a drive mechanism for rotating the stirring blade.

  In the thirteenth feature configuration, as described in the thirteenth aspect, in addition to the twelfth feature configuration described above, the agitating blade may cause the steam that has entered the shaft seal chamber to enter the shaft seal chamber. In the inner wall surface of the shaft sealing chamber, the second shaft sealing mechanism is guided to the vicinity of the bearing holding the output shaft on the electric motor side.

  According to the above-described configuration, the airflow generated by the stirring blade cools the vicinity of the bearing that holds the output shaft on the motor side from the second shaft sealing mechanism on the inner wall surface of the shaft sealing chamber, thereby Since the bearing that generates heat by friction due to temperature rise or rotation of the output shaft can be indirectly cooled, frictional resistance due to thermal expansion of the bearing can be reduced. Further, when the viscosity of the lubricating oil of the bearing decreases due to heat generation, there is a risk that oil film formation is insufficient and abnormal wear or seizure may occur, but as described above, the bearing can be cooled. The trouble can be avoided. Therefore, it is possible to cope with high-speed rotation of the electric motor with the same bearing.

  As described above, according to the present invention, it is possible to provide an inexpensive underwater rotating device that does not require lubricating oil for the shaft seal mechanism.

Schematic of mixed flow pump according to the present invention (A) is a first explanatory view of a mixed flow pump, (b) is an AA end view of (a). (A) is 2nd explanatory drawing of a mixed flow pump, (b) is 3rd explanatory drawing of a mixed flow pump. (A) is a fourth explanatory view of a mixed flow pump, (b) is a BB end view of (a). (A) is a fifth explanatory view of the mixed flow pump, (b) is a CC end view of (a), (c) is an explanatory view of an angle formed by the shaft core of the output shaft and the heat sink. (A) is the sixth explanatory diagram of the mixed flow pump, (b) is the seventh explanatory diagram of the mixed flow pump. (A) is the eighth explanatory diagram of the mixed flow pump, (b) is the ninth explanatory diagram of the mixed flow pump. (A) is explanatory drawing of the heat sink which shows another embodiment, (b) is explanatory drawing of the heat sink which shows another embodiment. Illustration of conventional submersible pump

  Hereinafter, embodiments of the underwater rotating device according to the present invention will be described.

  As shown in FIG. 1, a vertical-shaft mixed flow pump 1 as an example of an underwater rotating device used for water supply or drainage contains an electric motor chamber 5 in which an electric motor 4 is accommodated, electrical components, etc., and a power supply cable 11. A suction bell that houses a fixed motor cover 12, a connection chamber 35 to which the power supply cable 11 and electrical components are connected, and an impeller 3 connected to the output shaft 2 of the motor 4. 36, a shaft sealing chamber 6 provided between the motor chamber 5 and the impeller 3, and a pump casing 13 including the shaft sealing chamber 6 and the discharge port 16 and connected to the suction bell 36. Electric power from a control panel installed on the ground is supplied to the electric motor 4 through the power supply cable 11, and the electric motor 4 rotates the impeller 3.

  The pump casing 13 is integrally formed by casting with the hollow shaft seal chamber 6 through the four guide vanes 17 formed in the circumferential direction on the inner wall portion 13a of the pump casing 13 with a discharge port 16 formed in the upper part. The space formed between the inner wall portion 13a and the outer surface 6a of the peripheral wall portion of the shaft sealing chamber 6 is configured to be a water flow path 14.

  The output shaft 2 of the electric motor 4 is vertically driven by a lower bearing 19 installed in a lower bracket 18 provided in the lower part of the electric motor room 5 and an upper bearing 21 installed in an upper bracket 20 provided in the upper part of the electric motor room 5. The lower part of the output shaft 2 is arranged to penetrate the shaft sealing chamber 6 in the vertical direction, and the impeller 3 is connected to the lower end portion thereof.

  The lower bearing 19 and the upper bearing 21 are each composed of a non-water-filled bearing such as a rolling bearing or a sliding bearing. This eliminates the need for the lubricating water and lubricating water injection mechanism of the bearing and the lubricating oil and lubricating oil injection mechanism.

  When the output shaft 2 of the electric motor 4 rotationally drives the impeller 3, water is sucked from the suction port 15 of the suction bell 36, guided by the guide blade 17, discharged from the discharge port 16, and arranged on the outer periphery of the pump casing 13. The discharged discharge pipe 22 is discharged.

  The shaft sealing chamber 6 is shaft sealed by a first shaft sealing mechanism 7 provided on the impeller 3 side of the output shaft 2 and a second shaft sealing mechanism 8 provided on the motor chamber 5 side.

  The electric motor chamber 5 is double-sealed by a first shaft sealing mechanism 7 and a second shaft sealing mechanism 8 so that water does not enter.

  The first shaft sealing mechanism 7 is constituted by a mechanical seal. The mechanical seal (first shaft sealing mechanism 7) is composed of a rotating ring 7a and a fixed ring 7b. The rotating ring 7a is fixed to the output shaft 2 and rotates with the rotation of the output shaft 2, and an O-ring is formed on the shaft sealing chamber 6 side. A seal surface is formed by a contact surface with the fixed ring 7b fixed through 7c. Between the rotary ring 7a and the output shaft 2, an O-ring 7d is used to prevent leakage. The O-ring 7d is deformed according to the vibration and eccentricity of the output shaft 2, and prevents the leakage of the role of buffering between the rotary ring 7a and the output shaft 2.

  Further, the mechanical seal (first shaft sealing mechanism 7) includes a spring 7e as an urging member. The rotating ring 7a is urged by the spring 7e to the fixed ring 7b, and the seal surface is kept in a constant contact state. . The sealing surface has a very small gap and a thin water film is formed. The mechanical seal (first shaft sealing mechanism 7) is lubricated and cooled by water on the impeller 3 side.

  The rotating ring 7a and the fixed ring 7b are made of carbon, silicon carbide (SiC), cemented carbide, or chromium oxide coating, and the O-rings 7c and 7d are made of an elastic body such as synthetic rubber or synthetic resin.

  The second shaft sealing mechanism 8 is constituted by an oil seal. In the oil seal (second shaft sealing mechanism 8), a ring-shaped lip 8a disposed around the output shaft 2 is fastened by a spring 8b, and a seal surface is formed by the inner peripheral surface of the lip 8a and the outer peripheral surface of the output shaft 2. Thus, even if the first shaft sealing mechanism 7 is broken and water enters the shaft sealing chamber 6 by providing the double shaft sealing mechanism, the second shaft sealing mechanism 8 is provided. As a result, water can be prevented from entering the electric motor chamber 5, so that the possibility of electric leakage of the electric motor 4 can be reduced.

  The second shaft sealing mechanism 8 may be a shaft sealing mechanism such as a non-water-filled mechanical seal, a V-ring, or an end surface sliding rubber seal. A shaft seal mechanism that does not require lubrication and cooling with a lubricant is preferably used.

  Thus, the shaft sealing chamber 6 is sealed by the first shaft sealing mechanism 7 provided on the impeller 3 side of the output shaft 2, and the second shaft sealing mechanism 8 does not require lubricating oil. This eliminates the need for periodic replacement work and disposal of replaced lubricating oil. Further, for example, even if the first shaft sealing mechanism 7 is broken, there is no possibility that the lubricating oil leaks into the water and pollutes the environment because no lubricating oil is used in the shaft sealing chamber 6. Further, since no lubricating oil is required, it is not necessary to form a lubricating oil injection passage, a discharge passage and an air passage communicating with the shaft sealing chamber 6, so that the structure of the shaft sealing chamber 6 and the pump casing 13 is simplified. It can be manufactured at low cost.

  As described above, the shaft sealing chamber 6 is shaft sealed by the first shaft sealing mechanism 7, but water evaporates due to sliding friction of the seal surface of the first shaft sealing mechanism 7, and the shaft sealing chamber 6 enters the shaft sealing chamber 6. Steam may enter.

  Therefore, the shaft seal chamber 6 is configured to function as a saturated steam chamber that condenses the steam that has entered the shaft seal chamber 6 from the first shaft seal mechanism 7.

  The outer surface 6 a of the peripheral wall portion of the shaft sealing chamber 6 is integrally formed by casting via the pump casing 13 and the guide vanes 17 and is in contact with water flowing through the flow path 14. Therefore, the outer peripheral surface 6a is always cooled by the water flowing through the flow path 14. That is, the shaft seal chamber 6 is cooled by water, and the vapor that has entered the shaft seal chamber 6 is condensed in the shaft seal chamber 6 when it is cooled to the saturation temperature or lower.

  Further, the shaft sealing chamber 6 is provided with a heat exchange mechanism that promotes the condensation of the vapor that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7. Furthermore, an openable / closable drain mechanism 9 is formed at the bottom of the shaft seal chamber 6 for draining condensed water to the outside.

  As shown in FIGS. 2A and 2B, the heat exchange mechanism is formed to extend horizontally from the inner surface 6 b of the peripheral wall portion of the shaft sealing chamber 6 toward the output shaft 2, and from the first shaft sealing mechanism 7. It is comprised with the heat sink 23 which condenses the vapor | steam which entered the shaft sealing chamber 6 on the surface. The heat radiating plate 23 has a disk shape in which an opening 23 a through which the output shaft 2 is inserted is formed at the center. The opening 23a may be large enough to be inserted through the output shaft 2 or may be sufficiently larger than the diameter of the output shaft 2.

  Furthermore, in this embodiment, the heat exchange mechanism is configured by a single heat radiating plate 23, but may be configured by providing a plurality of disk-shaped heat radiating plates in the direction of the axis CL. When the number of heat sinks is increased, the surface area of the heat exchange mechanism is increased, so that the shaft seal chamber 6 is further cooled, and the steam is more likely to come into contact with the heat sink 23, so that the steam that has entered the shaft seal chamber 6 can be more reliably removed. Condensation can occur.

  Further, in this embodiment, the heat exchange mechanism is configured by the disk-shaped radiator plate 23. However, as shown in FIG. 8A, the heat exchange mechanism is divided into a semi-disc shape, a rectangle shape, a rod shape, or the like. There may be, and it is not limited to a disk-shaped heat sink.

  The heat radiating plate 23 is integrally formed with the inner surface 6b of the peripheral wall portion of the shaft sealing chamber 6 by casting, and is configured to efficiently conduct heat to the peripheral wall portion of the shaft sealing chamber 6.

  On the lower surface of the heat radiating plate 23, an inclined surface 24 that is inclined toward the drain mechanism 9 is provided so as to serve as a guide plate that guides the condensed water on the surface toward the drain mechanism 9. The condensed water on the surface of the radiator plate 23 is surely guided to the drain mechanism 9 along the surface of the inclined surface 24, so that the condensed water is easily drained. Note that an opening 23b is formed at the end of the heat radiating plate 23 on the drain mechanism 9 side to allow condensed water on the upper surface to pass through the lower surface.

  As described above, the shaft seal chamber 6 functions as a saturated vapor chamber that condenses the vapor that has entered the shaft seal chamber 6 from the first shaft seal mechanism 7, and the steam is condensed in the shaft seal chamber 6. Therefore, it is possible to reduce the possibility that the steam that has entered the motor 6 enters the motor chamber 5 as it is to corrode the lower bearing 19 and the upper bearing 21, deteriorate the insulation of the motor 4, or cause the motor 4 to break down. The condensed water collected at the bottom of the shaft seal chamber 6 can be used for cooling the first shaft seal mechanism 7.

  Further, the shaft seal chamber 6 is provided with a water level sensor 10. The water level sensor 10 is preferably a float type or an electrode type.

  When the water level sensor 10 detects that the dew condensation water accumulated in the shaft seal chamber 6 has reached a predetermined amount, the water level sensor 10 is configured to notify the worker of the fact by an alarm device (not shown). When the worker confirms the alarm, the worker raises the mixed flow pump 1 and drains the condensed water in the shaft seal chamber 6 from the drain mechanism 9. As described above, by providing the water level sensor 10, it is possible to detect that the condensed water accumulated in the shaft seal chamber 6 has reached a predetermined amount without lifting the mixed flow pump 1 to the ground and checking by an operator. It is. Moreover, if the pace at which the dew condensation water is stored is earlier than the pace assumed in advance, it can be predicted that the first shaft sealing mechanism 7 is broken and water has entered the shaft sealing chamber 6.

  In the present embodiment, the configuration in which the water level sensor 10 is disposed so as to be positioned above the upper surface of the radiator plate 23 has been described. However, an opening is formed in the radiator plate 23 and the water level sensor 10 is inserted through the opening. The water level sensor 10 may be arranged so as to be positioned below the lower surface of the heat sink 23.

  Furthermore, in addition to the water level sensor 10 provided in the shaft seal chamber 6, a water immersion sensor may be provided in the electric motor chamber 5. For example, vapor that has not condensed in the shaft seal chamber 6 enters the motor chamber 5 from the second shaft seal mechanism 8 to cause condensation, or both the first shaft seal mechanism 7 and the second shaft seal mechanism 8 have failed. Sometimes, it can be detected that water has entered the electric motor chamber 5.

  The drain mechanism 9 includes a check valve (not shown) at the drain port 9a of the drain mechanism 9 and a gas supply mechanism that supplies pressurized gas to the shaft seal chamber 6 from the ground via a hose or a pipe. In addition, the condensed water stored in the shaft sealing chamber 6 by the gas supply mechanism may be drained through the check valve.

  Pressurizing the inside of the shaft sealing chamber 6 with the pressurizing gas supplied by the gas supply mechanism to open the check valve provided in the drain mechanism 9 to reliably drain the condensed water stored in the shaft sealing chamber 6. it can. Furthermore, the mixed flow pump 1 is submerged by supplying pressurized gas to the shaft sealing chamber 6 from a gas supply mechanism installed on the ground by a hose or a pipe. Also, the condensed water stored in the shaft sealing chamber 6 is removed from the outside. It can also be drained. When the water level sucked by the mixed flow pump 1 becomes a level equal to or lower than the check valve, the check valve is opened by the pressure of the condensed water in the shaft seal chamber 6, and the condensed water is automatically drained from the drain mechanism. Is done.

  Further, a hose or a pipe may be connected to the drain port 9a of the drain mechanism 9 from the ground, and the condensed water may be sucked by a suction mechanism such as a vacuum pump.

  You may comprise the disk-shaped heat sink which comprises a heat exchange mechanism as follows. In addition, about the structure similar to embodiment mentioned above to Fig.2 (a), (b), the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 3A, the heat radiating plate 25 is directed toward the bottom portion of the shaft seal chamber 6 so that the entire heat radiating plate 25 serves as a guide plate for guiding condensed water on the surface thereof toward the bottom portion of the shaft seal chamber 6. It is composed of an inclined surface inclined. More specifically, an opening through which the output shaft 2 is inserted is formed in the center of the heat radiating plate 25, and the upper surface of the heat radiating plate 25 is an inclined surface that is inclined downward from the inner surface 6 b of the peripheral wall portion of the shaft sealing chamber 6 toward the opening. The lower surface of the heat radiating plate 25 is formed of an inclined surface that is inclined downward from the opening toward the inner surface 6b of the peripheral wall portion of the shaft sealing chamber 6.

  With this configuration, the dew condensation water on the upper surface of the heat radiating plate 25 is guided to the central opening through the inclined surface constituting the upper surface, flows to the lower surface side of the heat radiating plate 25, and the heat radiating plate 25. Condensed water on the lower surface of the shaft is guided to the inner surface 6b of the peripheral wall portion of the shaft sealing chamber 6 through the inclined surface forming the lower surface, is guided to the bottom portion of the shaft sealing chamber 6, and accumulates at the bottom portion of the shaft sealing chamber 6. The condensed water is guided to the drain mechanism 9.

  Further, as shown in FIG. 3B, the heat radiating plate 26 is inclined toward the drain mechanism 9 so that the whole of the heat radiating plate 26 becomes a guide plate for guiding the condensed water on the surface thereof toward the drain mechanism 9. You may comprise an inclined surface. More specifically, the heat radiating plate 26 is configured to be inclined so that the closer to the drain mechanism 9 is lower and the farther is higher. An opening through which the output shaft 2 is inserted is formed at the center of the heat radiating plate 26, and an opening 26 a through which condensed water on the upper surface passes through the lower surface is formed at the end on the drain mechanism 9 side.

  Thus, since the whole heat sink 26 inclines toward the drain mechanism 9, the dew condensation water on the surface of the heat sink 26 is reliably guide | induced to the drain mechanism 9 along the surface.

  Moreover, you may comprise the heat sink which comprises a heat exchange mechanism as follows. In addition, about the structure similar to embodiment mentioned above to Fig.2 (a), (b), the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 4A, the heat exchanging mechanism is directed in the direction of the axis CL from the peripheral wall inner surface 6b of the shaft sealing chamber 6 toward the output shaft 2 so as to radiate from the axis CL of the output shaft 2. It is formed with a plurality of heat dissipating plates 27 that extend with a width and allow the vapor that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7 to condense on the surface thereof.

  As shown in FIG. 4B, the shaft sealing chamber 6 has a total of eight heat radiating plates 27 that radiate from the axis CL every 45 degrees in the circumferential direction, and the surface of the heat radiating plate 27. Are arranged around the axis CL so as to face each other along the direction of the axis CL of the output shaft 2. In the present embodiment, the number of the heat radiating plates 27 is eight, but the number of the heat radiating plates 27 may be two or more, for example, four or six. The water level sensor 10 is disposed at an appropriate position between the opposed surfaces of the adjacent heat radiating plates 27. Moreover, as shown in FIG.8 (b), the heat sink 27 does not need to oppose along the axial center CL.

  By configuring the heat radiating plate 27 in this way, the vapor that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7 passes along the surface of the heat radiating plate 27 to the second shaft sealing mechanism 8 on the motor chamber 5 side. Will move. Since the contact time with the heat radiating plate 27 until the steam moves from the first shaft sealing mechanism 7 side to the second shaft sealing mechanism 8 side becomes longer, condensation tends to occur. The heat radiating plate 27 may be formed from the bottom surface to the upper end of the shaft seal chamber 6. If it is this structure, the contact time of a vapor | steam and the heat sink 27 will become longer, and also it will become easy to dew condensation.

  Further, when the heat radiating plate constituting the heat exchanging mechanism is arranged so as to radiate from the axis CL of the output shaft 2, the surface of the heat radiating plate 28 is output as shown in FIGS. You may arrange | position so that it may oppose along the axis | shaft CL direction of the axis | shaft 2 along a predetermined angle, for example, the direction which cross | intersects at 75 degree | times as shown in FIG.5 (c). The angle is set in the range of greater than 0 degrees and less than 90 degrees. The angle formed between the heat sink 28 and the axis CL may be set alternately. Alternatively, the angle formed between the heat sink 28 and the axis CL may be set differently.

  Moreover, the heat sink 28 may arrange | position every other heat sink 28 of FIG.5 (b), for example, leaving a clearance gap in the circumferential direction of the axial center CL. Furthermore, a plurality of stages may be arranged in the direction of the axis CL, and in this case, the surface area of the heat exchange mechanism increases, so that the vapor is more likely to condense.

  Further, the shaft sealing chamber 6 may be configured as follows. In addition, about the structure similar to embodiment mentioned above to Fig.2 (a), (b), the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 6 (a), a cylindrical recess 30 for storing condensed water condensed in the shaft seal chamber 6 is formed around the output shaft 2 in the bottom surface of the shaft seal chamber 6. The stored dew condensation water is configured to be surely in contact with the first shaft sealing mechanism 7. The heat radiating plate 29 constituting the heat exchanging mechanism is preferably configured to be inclined downward from the inner surface 6b of the peripheral wall portion of the shaft seal chamber 6 toward the concave portion 30 so as to guide the condensed water on the surface to the concave portion 30.

  According to the above configuration, the dew condensation water accumulates in the recess 30 and comes into contact with the first shaft sealing mechanism 7 to help cool the first shaft sealing mechanism 7 and enters the shaft sealing chamber 6 via the first shaft sealing mechanism 7. It is possible to capture incoming steam and reduce the risk of the steam entering the motor chamber 5 via the second shaft sealing mechanism 8.

  As shown in FIG. 6B, a cylindrical water storage wall 31 may be provided around the output shaft 2 so that condensed water is stored along the output shaft 2.

  According to the above configuration, the condensed water accumulates in the water storage wall 31 and comes into contact with the first shaft sealing mechanism 7, assists cooling of the first shaft sealing mechanism 7, and enters the shaft sealing chamber 6 via the first shaft sealing mechanism 7. It is possible to capture the invading steam and reduce the possibility that the steam enters the electric motor chamber 5 via the second shaft sealing mechanism 8.

  Moreover, the structure provided with both the recessed part 30 shown to Fig.6 (a) and the water storage wall 31 shown to FIG.6 (b) in the shaft seal chamber 6 may be sufficient.

  Further, as shown in FIG. 7A, the shaft sealing chamber 6 may be provided with a stirring blade 34 that rotates as the output shaft 2 rotates. The stirring blade 34 is installed according to the rotation direction of the output shaft 2 so as to guide the steam that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7 toward the heat radiating plate 32 that functions as a heat exchange mechanism. . The heat radiating plate 32 has a disk shape with an opening through which the output shaft 2 is inserted at the center.

  According to the above-described configuration, the rotation of the stirring blade 34 generates an air flow in the shaft sealing chamber 6, and the steam that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7 enters the heat radiating plate 32 as a heat exchange mechanism. Since it guides towards, vapor | steam will be made to collide positively with the heat sink 32, and dew condensation will occur. In addition, since the air flow itself generated by the stirring blade 34 is cooled by the heat radiating plate 32, the temperature in the shaft seal chamber 6 is lowered and the vapor is likely to be condensed. In addition, since the stirring blade 34 rotates with the rotation of the output shaft 2, it is not necessary to separately provide a drive mechanism for rotating the stirring blade 34.

  Further, as shown in FIG. 7B, when the shaft sealing chamber 6 is provided with the stirring blade 34, the stirring blade 34 removes the vapor that has entered the shaft sealing chamber 6 from the first shaft sealing mechanism 7 into the shaft sealing chamber. The inner wall surface of 6 may be configured to be guided to the vicinity of the lower bearing 19 that holds the output shaft 2 on the electric motor 4 side from the second shaft sealing mechanism 8. The heat radiating plate 33 is arranged so that it radiates from the axis CL every 45 degrees in the circumferential direction, and the surface of the heat radiating plate 33 faces the direction of the axis CL of the output shaft 2. Yes. In addition, it is preferable to comprise the heat sink 33 in the shape which does not disturb the airflow which the stirring blade 34 generates, the shape which guides an airflow, or arrange | positions it in the position.

  By directing the airflow generated by the rotation of the stirring blade 34 toward the lower bearing 19 and facilitating dew condensation around the lower bearing 19, the lower portion that generates heat due to the temperature rise in the motor chamber 5 and friction due to the rotation of the output shaft 2 Since the bearing 19 can be indirectly cooled, the frictional resistance due to the thermal expansion of the lower bearing 19 can be reduced. Further, when the viscosity of the lubricating oil of the lower bearing 19 is reduced due to heat generation, the oil film is not sufficiently formed and abnormal bearing wear or seizure may occur. However, as described above, the lower bearing 19 may be cooled. Since this is possible, such a problem can be avoided. Therefore, it is possible to cope with high-speed rotation of the electric motor with the same bearing.

  Further, an air flow toward the bottom of the shaft seal chamber 6 may be generated in the shaft seal chamber 6 by the rotation of the stirring blade 34, and the vapor may be directly condensed at the bottom of the shaft seal chamber 6 and stored.

  In any of the above-described embodiments, the heat radiating plate has been described as a flat plate, but the surface may have irregularities. By having irregularities on the surface of the heat sink, the surface area increases and the vapor is more likely to condense.

  In any of the above-described embodiments, the configuration including the heat radiating plate as the heat exchange mechanism has been described. However, the heat exchange mechanism is disposed inside the shaft seal chamber and is capable of passing water around the shaft seal chamber. You may comprise by piping. A part of the water pumped by the submersible pump is passed through the cooling pipe to cool the pipe surface, and the vapor that has entered the shaft seal chamber is condensed on the pipe surface. Moreover, it is good also considering the surrounding wall part inner surface 6b itself of a shaft seal chamber as a heat exchange mechanism, without providing a heat sink and cooling piping.

  In the embodiment described above, the submersible rotating device has been described with respect to the vertical mixed flow pump in which the output shaft is arranged in the vertical direction, but may be a horizontal mixed flow pump in which the output shaft is arranged in the horizontal direction. . Moreover, not only a mixed flow pump but submersible pumps, such as an axial flow pump and a centrifugal pump, may be sufficient. Furthermore, the submersible pump can be applied to a submersible pump used for water supply or drainage in various fields such as clean water, sewage, and industrial water.

  The submersible rotating device is not limited to the submersible pump. It may be an underwater mixer that is installed in a water tank and includes a shaft seal chamber between an impeller that stirs water and an electric motor that rotates the impeller. An electric motor chamber that houses an electric motor that rotationally drives an impeller coupled to an output shaft; and a shaft sealing chamber that is provided between the electric motor chamber and the impeller, wherein the shaft sealing chamber is the output shaft. Of these, any underwater rotating device that is shaft-sealed by a first shaft-seal mechanism provided on the impeller side and a second shaft-seal mechanism provided on the motor chamber side may be used.

  Each of the above-described embodiments is an example of the present invention, and the present invention is not limited by the description. The specific configuration of each part can be appropriately changed and designed within the range where the effects of the present invention are exhibited. Needless to say.

1: Mixed flow pump 2: Output shaft 3: Impeller 4: Motor 5: Motor chamber 6: Shaft seal chamber 6a: Outer wall portion outer surface 6b: Perimeter wall portion inner surface 7: First shaft seal mechanism 7a: Rotating ring 7b: Fixed ring 7c: O-ring 7d: O-ring 7e: Spring 8: Second shaft sealing mechanism 8a: Lip 8b: Spring 9: Drain mechanism 9a: Drain port 10: Water level sensor 11: Power supply cable 12: Motor cover 13: Pump casing 14: Flow path 15: Suction port 16: Discharge port 17: Guide vane 18: Lower bracket 19: Lower bearing 20: Upper bracket 21: Upper bearing 22: Discharge pipe 23: Heat sink 23a: Opening 23b: Opening 24: Inclined surface 25: Heat sink 26: Heat sink 27: Heat sink 30: Recess 31: Water storage wall 32: Heat sink 33: Heat sink 34: Stirring blade 35: Connection chamber 36: Suction bell

Claims (13)

An electric motor chamber that houses an electric motor that rotationally drives an impeller coupled to an output shaft; and a shaft sealing chamber that is provided between the electric motor chamber and the impeller, wherein the shaft sealing chamber is the output shaft. Of which the shaft is sealed by a first shaft sealing mechanism provided on the impeller side and a second shaft sealing mechanism provided on the motor chamber side, and no lubricating oil is sealed in the shaft sealing chamber. Medium rotating equipment,
Condensation of steam that has entered the shaft sealing chamber from the first shaft sealing mechanism so that the shaft sealing chamber functions as a saturated steam chamber that condenses the steam that has entered the shaft sealing chamber from the first shaft sealing mechanism. An underwater rotating device configured to include a heat exchange mechanism for promoting the shaft seal chamber . The underwater rotating device according to claim 1, wherein an outer surface of a peripheral wall portion of the shaft sealing chamber is configured to contact a flow path of water discharged from the impeller. The heat exchange mechanism is formed so as to extend from the inner surface of the peripheral wall portion of the shaft seal chamber toward the output shaft, and allows the vapor that has entered the shaft seal chamber from the first shaft seal mechanism to condense on the surface thereof. The underwater rotating device according to claim 1 or 2 , comprising a plurality of heat sinks. The heat exchange mechanism is formed to extend from the inner surface of the peripheral wall portion of the shaft sealing chamber toward the output shaft so as to radiate from the shaft center of the output shaft, and from the first shaft sealing mechanism to the shaft sealing chamber. The underwater rotating device according to claim 1 or 2 , comprising a plurality of heat radiating plates that condense the vapor that has entered the surface on the surface thereof.   The underwater rotating device according to claim 4, wherein surfaces of the plurality of heat radiating plates are arranged so as to face each other along an axial direction of the output shaft.   The underwater rotating device according to claim 4, wherein surfaces of the plurality of heat radiating plates are arranged so as to face each other along a direction intersecting with an axial direction of the output shaft.   The shaft sealing chamber includes an openable / closable drain mechanism for draining condensed water to the outside, and the heat sink is a guide plate for guiding the condensed water on the surface toward the drain mechanism. The underwater rotating device according to any one of claims 3 to 6, further comprising an inclined surface inclined toward the surface.   The drain mechanism includes a check valve, and a gas supply mechanism that supplies pressurizing gas to the shaft sealing chamber. The condensed water stored in the shaft sealing chamber by the gas supply mechanism is supplied with the check valve. The underwater rotating device according to claim 7, wherein the rotating device is configured to drain water through the underwater rotating device.   The underwater rotating device according to any one of claims 1 to 8, wherein the shaft seal chamber includes a water level sensor that detects that condensed water has reached a predetermined amount.   The output shaft is installed in a vertical posture, and a concave portion is formed around the output shaft in the bottom surface of the shaft sealing chamber so that condensed water is in contact with the first shaft sealing mechanism. The underwater rotating device according to any one of the above.   The underwater rotation according to any one of claims 1 to 10, wherein the output shaft is installed in a vertical posture, and a water storage wall is provided around the output shaft so that condensed water is stored along the output shaft. machine. The shaft sealing chamber is provided with a stirring blade that rotates as the output shaft rotates, and the steam that has entered the shaft sealing chamber from the first shaft sealing mechanism is guided toward the heat exchange mechanism by the stirring blade. water rotating device according to claim 1 or al 11 that is configured to.   The agitating blade causes the vapor that has entered the shaft sealing chamber from the first shaft sealing mechanism to be close to the bearing that holds the output shaft on the electric motor side of the second shaft sealing mechanism on the inner wall surface of the shaft sealing chamber. The underwater rotating device according to claim 12 configured to guide.

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