Water resistant type outer bearing device for vertical shaft pump

Abstract

To provide a water resistant type outer bearing device for a vertical shaft pump which can prevent exterior water from invading.SOLUTION: A water resistant type outer bearing device 43 includes bearings 47, 48 rotatably supporting a rotation shaft 15, a bearing housing 51 having a bearing chamber 50 inside thereof in which the bearings 47, 48 are accommodated, a bearing cover 52 covering the bearing chamber 50, a journal 62 fixed to an outer peripheral surface of the rotation shaft 15, an adjustment nut 60 in contact with an upper face of the journal 62, a nut cover 200 accommodating the adjustment nut 60, a first seal 201 for sealing a gap between the bearing cover 52 and an outer peripheral surface of the journal 62, a second seal 202 for sealing a gap between the nut cover 200 and the outer peripheral surface of the rotation shaft 15, and a third seal 203 for sealing a gap between the nut cover 200 and the journal 62. The adjustment nut 60 is screwed on a thread part 64 formed on the outer peripheral surface of the rotation shaft 15.SELECTED DRAWING: Figure 30

Description

[Technical field]

[0001] The present invention relates to a water-resistant outer bearing device that rotatably supports the rotating shaft of a vertical pump, and more particularly to a water-resistant outer bearing device that can prevent water from entering a bearing chamber. [Background technology]

[0002] Pumping stations that drain storm water use vertical pumps with a rotating shaft that extends vertically. In pumping stations where the vertical pump is installed below ground level, there is concern that the pump room may be flooded during the approach of a large typhoon. If flooding of such pumping stations is assumed, a sufficient flood prevention measure is to install the drive machine, reducer, electrical equipment, etc. that drives the vertical pump in the prime mover room that is above ground level.

[0003] However, there is currently no established technology to prevent flooding (water resistance) of the vertical pump itself. If a vertical pump becomes flooded, the outer bearing device on top of the vertical pump is thought to be the most susceptible to damage. The outer bearing device is installed above the pump casing, and is positioned so that it does not come into contact with the water pumped up by the vertical pump.

[0004] A bearing that supports the rotating shaft of the vertical pump is provided inside the bearing chamber of the outer bearing device. If water gets into the bearing chamber and comes into contact with the bearing, the bearing will corrode and eventually the vertical pump will be unable to operate. Therefore, bearing devices with water-resistant measures have been proposed in the past, as shown below. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-153541 A [Patent Document 2] Japanese Patent Application Publication No. 11-294690 Summary of the Invention [Problem to be solved by the invention]

[0006] The above-mentioned Patent Document 1 discloses a structure in which a double cylindrical member is raised from the discharge elbow to the flooding set water level (flooding water level) so as to surround the bearing case. However, the top of the double cylindrical member is open, and if the flooding level is higher than the double cylindrical member, water will enter the double cylindrical member. In addition, the structure is such that dust and dirt are likely to accumulate inside the double cylindrical member when the cooling fan is operated, and furthermore, it is necessary to remove the double cylindrical member to replenish oil in the bearing chamber, which is expected to cause problems with regular maintenance work.

[0007] The above-mentioned Patent Document 2 discloses a structure in which, when a pump becomes flooded, the water that has entered the bearing chamber is discharged to the outside together with some of the lubricating liquid, due to the difference in specific gravity between the water and the lubricating liquid (turbine oil, etc.) and the structure of the bearing case. However, since this technology is premised on the intrusion of water into the bearing chamber, in actual operation, the pump cannot be restarted after flooding without inspecting the bearings inside the bearing chamber. In addition, the need to discharge the lubricating liquid to the outside leaves concerns about environmental pollution.

[0008] Therefore, the present invention provides a water-resistant outer bearing device for a vertical pump that can prevent water from entering from the outside. [Means for solving the problem]

[0009] In one aspect, a water-resistant outer bearing device for supporting a rotating shaft of a vertical pump is provided, the water-resistant outer bearing device comprising: a bearing for rotatably supporting the rotating shaft; a bearing housing having a bearing chamber therein in which the bearing is accommodated; a bearing cover covering the bearing chamber; a journal fixed to the outer peripheral surface of the rotating shaft; an adjusting nut in contact with the upper surface of the journal; a nut cover accommodating the adjusting nut; a first seal for sealing a gap between the bearing cover and the outer peripheral surface of the journal; a second seal for sealing a gap between the nut cover and the outer peripheral surface of the rotating shaft; and a third seal for sealing a gap between the nut cover and the journal, wherein the adjusting nut is screwed into a threaded portion formed on the outer peripheral surface of the rotating shaft.

[0010] In one aspect, the nut cover is removably secured to the journal by a screw. In one aspect, the water-resistant outer bearing device further includes an air vent pipe removably connected to the journal, the air vent pipe communicating with an air vent passage formed inside the journal. In one embodiment, the water-resistant outer bearing device further includes a lower seal for sealing a gap between the bearing housing and the rotating shaft. In one aspect, the lower seal includes a fixed side member fixed to the bearing housing, a rotating side member fixed to the rotating shaft, and a seal element supported by the fixed side member and pressed against the rotating side member.

[0011] In one aspect, a water-resistant outer bearing device for supporting a rotating shaft of a vertical pump is provided, comprising a bearing for rotatably supporting the rotating shaft, a bearing housing having a bearing chamber therein in which the bearing is accommodated, an inner bearing cover covering the bearing chamber, an upper bearing cover covering the inner bearing cover, and an upper seal for sealing a gap between the upper bearing cover and the rotating shaft.

[0012] In one aspect, the water-resistant outer bearing device further includes a ventilation pipe extending upward from the upper bearing cover, the ventilation pipe communicating with the space between the upper bearing cover and the inner bearing cover, and the space communicating with the bearing chamber. In one aspect, the water-resistant outer bearing device further includes a vent pipe connected to the upper bearing cover and a float valve connected to the vent pipe, the vent pipe communicating with the space between the upper bearing cover and the inner bearing cover, and the space communicating with the bearing chamber. In one aspect, the water-resistant outer bearing device further includes a buffer tank fixed to the upper bearing cover, the buffer tank communicating with the space between the upper bearing cover and the inner bearing cover, and the space communicating with the bearing chamber. In one aspect, the water-resistant outer bearing device further includes an adjusting nut arranged in the space between the upper bearing cover and the inner bearing cover, and a journal fixed to the outer peripheral surface of the rotating shaft, the adjusting nut being screwed into a threaded portion formed on the outer peripheral surface of the rotating shaft, and the adjusting nut being in contact with the upper surface of the journal.

[0013] In one embodiment, the water-resistant outer bearing device further includes an upper seal positioning device that switches the position of the upper seal between a contact position in which the upper seal contacts a first outer peripheral surface of the rotating shaft and a non-contact position in which the upper seal is spaced apart from a second outer peripheral surface of the rotating shaft, the second outer peripheral surface having a smaller diameter than the first outer peripheral surface. In one aspect, the upper positioning device is configured to vertically position the upper seal. In one embodiment, the water-resistant outer bearing device further includes at least one spare upper seal arranged above the upper seal, and an upper seal storage container in which the spare upper seal is stored. In one aspect, the water-resistant outer bearing device further includes an upper movable sleeve having an inner peripheral thread portion screwed into an outer peripheral thread portion formed on the outer peripheral surface of the rotating shaft, and the upper movable sleeve is movable on the rotating shaft between a contact position in contact with the upper seal and a non-contact position away from the upper seal.

[0014] In one aspect, the upper seal is a magnetic fluid seal having an electromagnet that creates a magnetic field and a magnetic fluid disposed within the magnetic field. In one aspect, the upper seal is a gas expansion seal capable of contacting and disengaging from the shaft. In one embodiment, the water-resistant outer bearing device further includes a lower seal for sealing a gap between the bearing housing and the rotating shaft. In one aspect, the lower seal includes a fixed side member fixed to the bearing housing, a rotating side member fixed to the rotating shaft, and a seal element supported by the fixed side member and pressed against the rotating side member.

[0015] In one aspect, a water-resistant outer bearing device for supporting a rotating shaft of a vertical pump is provided, comprising a bearing for rotatably supporting the rotating shaft, a bearing housing having a bearing chamber therein in which the bearing is accommodated, a bearing cover covering the bearing chamber, a journal fixed to the outer peripheral surface of the rotating shaft, a seal holder in contact with the upper surface of the journal, a first seal for sealing a gap between the bearing cover and the outer peripheral surface of the journal, a second seal for sealing a gap between the seal holder and the outer peripheral surface of the rotating shaft, and a third seal for sealing a gap between the seal holder and the upper surface of the journal, wherein the second seal and the third seal are held by the seal holder.

[0016] In one embodiment, the seal holder is an adjustment nut that is screwed onto a threaded portion formed on an outer circumferential surface of the rotating shaft. In one embodiment, the water-resistant outer bearing device further includes an adjustment nut screwed into a threaded portion formed on the outer peripheral surface of the rotating shaft, and the seal holder is disposed between the adjustment nut and the journal. In one aspect, the water-resistant outer bearing device further includes an air vent pipe removably connected to the journal, the air vent pipe communicating with an air vent passage formed inside the journal. In one embodiment, the water-resistant outer bearing device further includes a lower seal for sealing a gap between the bearing housing and the rotating shaft. In one aspect, the lower seal includes a fixed side member fixed to the bearing housing, a rotating side member fixed to the rotating shaft, and a seal element supported by the fixed side member and pressed against the rotating side member.

[0017] In one aspect, a water-resistant outer bearing device for supporting a rotating shaft of a vertical pump is provided, comprising: a bearing for rotatably supporting the rotating shaft; a bearing housing having a bearing chamber therein in which the bearing is accommodated; a bearing cover covering the bearing chamber; a journal fixed to the outer peripheral surface of the rotating shaft; an adjusting nut screwed into a threaded portion formed on the outer peripheral surface of the rotating shaft; a coupling forming an enclosed space therein in which the adjusting nut and an upper end of the rotating shaft are disposed; a first seal for sealing a gap between the bearing cover and the outer peripheral surface of the journal; and a second seal for sealing a gap between the coupling and the journal.

[0018] In one aspect, the water-resistant outer bearing device further includes an air vent pipe removably connected to the journal, the air vent pipe communicating with an air vent passage formed inside the journal. In one embodiment, the water-resistant outer bearing device further includes a lower seal for sealing a gap between the bearing housing and the rotating shaft. In one aspect, the lower seal includes a fixed side member fixed to the bearing housing, a rotating side member fixed to the rotating shaft, and a seal element supported by the fixed side member and pressed against the rotating side member. Effect of the Invention

[0019] According to the above aspect, the bearing chamber is covered by a double wall structure of the inner bearing cover and the outer bearing cover, and the gap between the outer bearing cover and the rotating shaft is sealed by the upper seal. With this configuration, even if the water level rises and the water-resistant outer bearing device is submerged, water can be prevented from entering the bearing chamber.

[0020] According to the above aspect, the first seal for sealing the gap between the bearing cover and the outer peripheral surface of the journal can prevent water from entering the bearing chamber through the gap between the bearing cover and the outer peripheral surface of the journal. Also, the second seal for sealing the gap between the nut cover and the outer peripheral surface of the rotating shaft and the third seal for sealing the gap between the nut cover and the journal can prevent water from entering the bearing chamber through the gap between the journal and the rotating shaft.

[0021] According to the above aspect, the first seal for sealing the gap between the bearing cover and the outer peripheral surface of the journal can prevent water from entering the bearing chamber through the gap between the bearing cover and the outer peripheral surface of the journal. Also, the second seal for sealing the gap between the seal holder and the outer peripheral surface of the rotating shaft and the third seal for sealing the gap between the seal holder and the journal can prevent water from entering the bearing chamber through the gap between the journal and the rotating shaft.

[0022] According to the above aspect, the first seal for sealing the gap between the bearing cover and the outer peripheral surface of the journal can prevent water from entering the bearing chamber through the gap between the bearing cover and the outer peripheral surface of the journal. Also, the second seal for sealing the gap between the coupling and the journal, and the coupling forming an internal sealed space in which the adjusting nut and the upper end of the rotating shaft are disposed, can prevent water from entering the bearing chamber through the gap between the journal and the rotating shaft and the gap between the adjusting nut and the rotating shaft. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic diagram showing one embodiment of a vertical pump. [Diagram 2] FIG. 2 is a cross-sectional view showing one embodiment of a water-resistant outer bearing device. [Diagram 3] FIG. 13 is an enlarged cross-sectional view of one embodiment of the upper seal. [Figure 4] FIG. 11 is an enlarged cross-sectional view of another embodiment of the upper seal. [Diagram 5] FIG. 1 illustrates one embodiment of a lower seal. [Figure 6] FIG. 13 illustrates another embodiment of the lower seal. [Figure 7] FIG. 11 is a cross-sectional view showing another embodiment of a water-resistant outer bearing device. [Figure 8] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 9] FIG. 2 is an enlarged cross-sectional view of an embodiment of a float valve. [Figure 10] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 11] 11 is a diagram showing a state in which the upper seal and the upper seal holder have been moved from the non-contact position shown in FIG. 10 to a contact position in which the upper seal is in contact with the outer circumferential surface of the rotating shaft. [Figure 12] 1 illustrates one embodiment of a lower seal positioning device. [Figure 13] 1 illustrates one embodiment of a lower seal positioning device. [Figure 14]A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 15] 15 is a diagram showing a state in which the upper seal and the upper seal holder have been moved from the non-contact position shown in FIG. 14 to a contact position in which the upper seal is in contact with the outer circumferential surface of the rotating shaft. [Figure 16] 16(a) to 16(c) are plan views showing some examples of spacers. [Figure 17] 1 illustrates one embodiment of a lower seal positioning device. [Figure 18] 1 illustrates one embodiment of a lower seal positioning device. [Figure 19] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 20] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 21] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 22] 13 is a diagram illustrating a state in which the upper movable sleeve is lowered to a contact position and the upper seal is in contact with the outer circumferential surface of the upper movable sleeve. FIG. [Diagram 23] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 24] 13 is a diagram illustrating a state in which the lower movable sleeve rises to a contact position and the lower seal comes into contact with the outer circumferential surface of the lower movable sleeve. FIG. [Diagram 25] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Figure 26] FIG. 13 is a cross-sectional view of one embodiment of an upper seal constructed from a gas expansion seal. [Figure 27] FIG. 13 shows the balloon ring in an inflated state. [Figure 28] FIG. 13 is a cross-sectional view of one embodiment of a lower seal constructed from a gas expansion seal. [Figure 29] FIG. 13 shows the balloon ring in an inflated state. [Diagram 30] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Diagram 31] FIG. 13 shows an embodiment in which a nut cover is secured to the journal by a screw. [Diagram 32] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Diagram 33] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. [Diagram 34] A cross-sectional view showing yet another embodiment of the water-resistant outer bearing device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a schematic diagram showing one embodiment of a vertical pump. As shown in Fig. 1, the vertical pump 1 is a pump for pumping up liquid in a suction tank 2. The vertical pump 1 shown in Fig. 1 is installed in a drainage pumping station for transporting drinking water, rainwater, agricultural water, etc.

[0025] The vertical pump 1 includes a rotating shaft 15 extending in the vertical direction, an impeller 10 fixed to the rotating shaft 15, and a pump casing 27 that forms a flow path for water pressurized by the impeller 10. The pump casing 27 includes a discharge bowl 24 in which the impeller 10 is disposed, a suction bell mouth 22 connected to the lower end of the discharge bowl 24, a lift pipe 28 connected to the upper end of the discharge bowl 24, a discharge bend 30 connected to the upper end of the lift pipe 28, and a discharge piping 34 connected to the discharge end of the discharge bend 30. The rotating shaft 15 is connected to a driving source 7 via a coupling 35. Examples of the driving source 7 include an electric motor, a diesel engine, and a gas turbine engine. The driving source 7 is installed on an installation floor 8 that is disposed above the pump installation floor 3.

[0026] The discharge bowl 24 and the suction bell mouth 22 are suspended within the suction tank 2 by a lifting pipe 28. The suction bell mouth 22 has a suction port 22a that opens downward, and the upper end of the suction bell mouth 22 is connected to the lower end of the discharge bowl 24. The suction port 22a is formed at the lower end of the pump casing 27.

[0027] The lift pipe 28 extends downward through an opening 5 formed in the pump installation floor 3 that constitutes the upper wall of the suction tank 2. A mounting flange 33 is fixed to the upper end of the lift pipe 28. The mounting flange 33 is fixed to the pump installation floor 3 by foundation bolts (not shown). The rotating shaft 15 extends vertically through the discharge bent pipe 30 and the lift pipe 28, and the lower end of the rotating shaft 15 is located in the discharge bowl 24.

[0028] The vertical pump 1 is equipped with a submerged bearing 41 and a water-resistant outer bearing device 43 for rotatably supporting the rotating shaft 15. The water-resistant outer bearing device 43 is disposed outside the flow path of the pump casing 27, and more specifically, is fixed to the upper part of the discharge bent pipe 30 that constitutes a part of the pump casing 27.

[0029] The rotating shaft 15 protrudes upward from the discharge bent pipe 30 and is connected to the drive source 7 via a coupling 35. A water-resistant outer bearing device 43 rotatably supports the part of the rotating shaft 15 protruding upward from the discharge bent pipe 30. The submerged bearing 41 is disposed in the discharge bowl 24 and supports the lower part of the rotating shaft 15. An additional submerged bearing supporting the rotating shaft 15 may be disposed in the lift pipe 28. An inspection port 45 is formed below the water-resistant outer bearing device 43 for inspecting the shaft seal device (not shown) that seals the gap between the rotating shaft 15 and the discharge bent pipe 30.

[0030] An inner bowl 25 is disposed inside the discharge bowl 24, and the inner bowl 25 is connected to the discharge bowl 24 by a plurality of guide vanes 37. An underwater bearing 41 is disposed within the inner bowl 25. The plurality of guide vanes 37 are disposed above the impeller 10 (on the discharge side). A liquid flow path is formed between the inner surface of the discharge bowl 24 and the outer surface of the inner bowl 25.

[0031] The impeller 10 is disposed in the suction sump 2. The driving source 7 rotates the rotary shaft 15 and the impeller 10 together. When the impeller 10 rotates, the liquid in the suction sump 2 is sucked in through the suction port 22a of the pump casing 27. As the impeller 10 rotates, the liquid is transported through the suction bell mouth 22, the discharge bowl 24, the lifting pipe 28, the discharge bend 30, and the discharge piping 34 that constitute the pump casing 27.

[0032] FIG. 2 is a cross-sectional view showing one embodiment of the waterproof outer bearing device 43. The waterproof outer bearing device 43 includes a bearing 47 and a bearing 48 that rotatably support the rotating shaft 15, a bearing housing 51 having a bearing chamber 50 in which the bearing 47 and the bearing 48 are accommodated, an inner bearing cover 52 that covers the bearing chamber 50, and an outer bearing cover 53 that covers the inner bearing cover 52. The bearing 47 is located above the bearing 48. The upper part of the rotating shaft 15 is connected to the coupling 35. More specifically, the coupling 35 has a lower coupling 35A that is connected to the rotating shaft 15 and an upper coupling 35B that is connected to the driving source 7 shown in FIG. 1, and the upper part of the rotating shaft 15 is accommodated in an accommodating hole 55 formed in the lower coupling 35A. The upper coupling 35B and the lower coupling 35A are fixed to each other by bolts and nuts not shown. A coupling cover that covers the entire coupling 35 may be provided.

[0033] The rotating shaft 15 has a threaded portion 57 formed on its outer circumferential surface. A set ring nut 58 is screwed onto the threaded portion 57. The lower surface of the lower coupling 35A is in contact with the set ring nut 58. When the set ring nut 58 is rotated, the set ring nut 58 moves vertically on the threaded portion 57. This set ring nut 58 is provided for determining the vertical positioning of the rotating shaft 15 and the entire coupling 35.

[0034] The rotating shaft 15 extends vertically through the entire water-resistant outer bearing device 43. The rotating shaft 15 may be composed of a single element, or may be composed of a rotating assembly including a main shaft and a shaft sleeve surrounding the periphery of the main shaft. The shaft sleeve forms a part of the outer circumferential surface of the rotating shaft 15.

[0035] The water-resistant outer bearing device 43 further includes an adjusting nut 60 disposed in the space Q between the outer bearing cover 53 and the inner bearing cover 52, and a journal 62 fixed to the outer circumferential surface of the rotating shaft 15. The journal 62 has a cylindrical shape, and the rotating shaft 15 extends through the journal 62. The journal 62 is capable of rotating integrally with the rotating shaft 15. The upper surface of the journal 62 is located in the space Q between the outer bearing cover 53 and the inner bearing cover 52, and the lower part of the journal 62 is located below the inner bearing cover 52 and within the bearing chamber 50.

[0036] The inner ring of the bearing 47 and the inner ring of the bearing 48 rotatably support the journal 62. Therefore, the rotating shaft 15 and the journal 62 are rotatably supported by the bearing 47 and the bearing 48. The outer ring of the bearing 47 and the outer ring of the bearing 48 are held in a bearing housing 51. In this embodiment, the bearing 47 is a radial rolling bearing configured to receive the radial load of the rotating shaft 15, and the bearing 48 is an angular rolling bearing configured to receive the radial load and the axial load of the rotating shaft 15. However, the configurations of the bearing 47 and the bearing 48 are not particularly limited as long as they can receive the radial load and the axial load of the rotating shaft 15.

[0037] The rotating shaft 15 extends through the adjusting nut 60. The adjusting nut 60 is screwed into a threaded portion 64 formed on the outer circumferential surface of the rotating shaft 15. More specifically, the adjusting nut 60 has an inner threaded portion 65 that is screwed into the threaded portion 64 of the rotating shaft 15. The adjusting nut 60 is in contact with the upper surface of the journal 62. When the adjusting nut 60 is rotated, the rotating shaft 15 moves up and down relative to the entire water-resistant outer bearing device 43. This adjusting nut 60 is provided for the purpose of positioning the rotating shaft 15 in the up and down direction relative to the water-resistant outer bearing device 43.

[0038] The water-resistant outer bearing device 43 has an oil cylinder 67 disposed inside the journal 62. The oil cylinder 67 is a cylindrical member extending upward from the lower part of the bearing housing 51, and the upper part of the oil cylinder 67 is located inside the journal 62. The oil cylinder 67 is provided to prevent the lubricating oil for the bearings 47 and 48 from leaking from the bearing chamber 50. The oil cylinder 67 extends upward to a position higher than the bearing 47, and extends downward to a position lower than the bearing 48. The rotating shaft 15 extends through the oil cylinder 67. The lower end of the oil cylinder 67 is fixed to the seal holder 68. In one embodiment, the lower end of the oil cylinder 67 may be fixed to the bearing housing 51.

[0039] The journal 62 has an air vent passage 70 therein. The upper end of the air vent passage 70 opens into the space Q between the outer bearing cover 53 and the inner bearing cover 52, and the lower end of the air vent passage 70 opens into an internal space 71 of the journal 62 in which the upper part of the oil cylinder 67 is disposed.

[0040] The waterproof outer bearing device 43 includes a ventilation pipe 73 extending upward from the outer bearing cover 53. The ventilation pipe 73 is removably connected to the outer bearing cover 53. The ventilation pipe 73 communicates with a space Q between the outer bearing cover 53 and the inner bearing cover 52, and the space Q communicates with the bearing chamber 50 through a through hole 74 formed in the inner bearing cover 52. The ventilation pipe 73 extends upward to a position higher than the coupling 35, and may extend upward to a position higher than the installation floor 8 on which the driving source 7 shown in FIG. 1 is installed, for example.

[0041] In the bearing chamber 50, a rotating part and a stationary part exist, and a pressure difference occurs between the rotating part and the stationary part. This pressure difference generates a force that draws in air from outside the bearing chamber 50. In addition, the air in the bearing chamber 50 expands due to heat generated by the bearings 47 and 48. This force that draws in the air and the expansion of the air allow air to circulate between the inside and outside of the bearing chamber 50 through the air vent passage 70 and the ventilation pipe 73. The air vent passage 70 communicates with the space Q between the outer bearing cover 53 and the inner bearing cover 52, and the ventilation pipe 73 communicates with this space Q. Since the ventilation pipe 73 extends upward, water will not flow into the space Q and the bearing chamber 50 through the ventilation pipe 73 even if the entire waterproof outer bearing device 43 is submerged in water.

[0042] The waterproof outer bearing device 43 further includes an upper seal 81 for sealing the gap between the outer bearing cover 53 and the rotating shaft 15, and a lower seal 82 for sealing the gap between the bearing housing 51 and the rotating shaft 15. The upper seal 81 and the lower seal 82 are sliding seals that come into sliding contact with the outer circumferential surface of the rotating shaft 15. The waterproof outer bearing device 43 further includes an intermediate seal 83 for sealing the gap between the inner bearing cover 52 and the journal 62. The intermediate seal 83 is a sliding seal that comes into sliding contact with the outer circumferential surface of the journal 62.

[0043] The lower seal 82 is held by a seal holder 68 arranged on the bottom surface of the bearing housing 51. A seal 69 (e.g., an O-ring) surrounding the periphery of the rotating shaft 15 is arranged between the bottom surface of the bearing housing 51 and the upper surface of the seal holder 68. The water-resistant outer bearing device 43 further includes a stationary seal 86 (e.g., an O-ring) arranged between the outer bearing cover 53 and the inner bearing cover 52, and a stationary seal 87 (e.g., an O-ring) arranged between the inner bearing cover 52 and the bearing housing 51.

[0044] The upper seal 81, the lower seal 82, the static seal 86, and the static seal 87 can prevent water from entering the space Q and the bearing chamber 50 when the entire water-resistant outer bearing device 43 is submerged. More specifically, the upper seal 81 prevents water from entering the gap between the outer bearing cover 53 and the rotating shaft 15, the static seal 86 prevents water from entering the gap between the outer bearing cover 53 and the inner bearing cover 52, the static seal 87 prevents water from entering the gap between the inner bearing cover 52 and the bearing housing 51, and the lower seal 82 prevents water from entering the gap between the bearing housing 51 and the rotating shaft 15. If there is no inspection hatch 45 shown in FIG. 1 or if the inspection hatch 45 can be closed with a sealing lid, the lower seal 82 may not be provided.

[0045] The portion of the outer circumferential surface of the rotating shaft 15 with which the upper seal 81 comes into contact is a smooth surface 90 formed by processing to smooth the surface (for example, surface grinding). The smooth surface 90 can improve contact with the upper seal 81 and more reliably prevent water intrusion. In addition, the smooth surface 90 can reduce wear of the upper seal 81, which is a sliding seal. The portion of the outer circumferential surface of the rotating shaft 15 with which the lower seal 82 comes into contact is also a smooth surface 91 formed by processing to smooth the surface (for example, surface grinding). The smooth surfaces 90, 91 may be formed on the outer circumferential surface of a shaft sleeve that constitutes a part of the rotating shaft 15.

[0046] FIG. 3 is an enlarged cross-sectional view showing one embodiment of the upper seal 81. As shown in FIG. 3, the upper seal 81 has a cross-sectional shape that opens to the outside. In the embodiment shown in FIG. 3, the upper seal 81 has a U-shaped cross-section that opens to the outside. When water enters the gap between the outer bearing cover 53 and the rotating shaft 15, the water pressure is applied to the upper seal 81, and the upper seal 81 expands outward. As a result, the lip of the upper seal 81 is pressed against the outer circumferential surface of the rotating shaft 15 by the water pressure, and thus the upper seal 81 can seal the gap between the outer bearing cover 53 and the rotating shaft 15.

[0047] The cross-sectional shape of the upper seal 81 is not particularly limited as long as it opens to the outside to receive water pressure. For example, as shown in Fig. 4, the upper seal 81 may have a V-shaped cross section that opens to the outside. Although not shown in the figure, the lower seal 82 may have the same configuration as the upper seal 81.

[0048] The intermediate seal 83, which is a sliding seal, may have the same structure as the upper seal 81 and the lower seal 82, or may have a seal of a simpler structure such as a felt ring.

[0049] Fig. 5 is a diagram showing another embodiment of the lower seal 82. In the embodiment shown in Fig. 5, the lower seal 82 is configured as a mechanical seal. More specifically, the lower seal 82 includes a fixed-side member 94 fixed to the bearing housing 51, a rotating-side member 95 fixed to the rotating shaft 15, a seal element 96 supported by the fixed-side member 94, and a spring 97 that presses the seal element 96 against the rotating-side member 95. The seal element 96 has an annular shape and is arranged around the rotating shaft 15.

[0050] Fig. 6 is a diagram showing still another embodiment of the lower seal 82. In the embodiment shown in Fig. 6, the lower seal 82 includes a fixed-side member 94 fixed to the bearing housing 51, a rotating-side member 95 fixed to the rotating shaft 15, and a seal element 96 supported by the fixed-side member 94 and pressed against the rotating-side member 95.

[0051] The lower end of the oil cylinder 67 is connected to the fixed-side member 94. An O-ring 98 is disposed between the bottom surface of the bearing housing 51 and the fixed-side member 94. The O-ring 98 extends so as to surround the rotating shaft 15. The gap between the bearing housing 51 and the fixed-side member 94 is sealed by the O-ring 98. In the embodiment shown in FIG. 6, the O-ring 98 is provided on the upper surface of the fixed-side member 94, but in one embodiment, the O-ring 98 may be provided on the bottom surface of the bearing housing 51.

[0052] The seal element 96 has an annular shape arranged around the rotating shaft 15. The seal element 96 is sandwiched between fixed side members 94. The configuration of the seal element 96 in Fig. 6 is not particularly limited, but for example, the seal element 96 may be a seal having a cross-sectional shape that opens outward to receive water pressure, as described with reference to Figs. 3 and 4.

[0053] FIG. 7 is a cross-sectional view showing another embodiment of the waterproof outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to FIG. 2 to FIG. 6, and therefore the overlapping description will be omitted. In the embodiment shown in FIG. 7, a buffer tank 100 is provided instead of the ventilation pipe 73 of FIG. 2. The buffer tank 100 is fixed to the outer bearing cover 53. The buffer tank 100 has an enclosed space S therein, and this enclosed space S communicates with the space Q between the outer bearing cover 53 and the inner bearing cover 52. The space Q communicates with the bearing chamber 50 through the through hole 74, and further communicates with the air vent passage 70.

[0054] The capacity of the buffer tank 100 (the volume of the sealed space S) is large enough to accommodate the force of sucking air generated in the bearing chamber 50 while the vertical pump 1 is in operation and the air flow caused by the expansion of the air. Therefore, the buffer tank 100 can ensure the required ventilation volume while the vertical pump 1 is in operation. Since the buffer tank 100 has no openings other than the opening communicating with the space Q, water will not flow into the buffer tank 100 even when the water-resistant outer bearing device 43 is submerged. The buffer tank 100 may also be applied as appropriate to the embodiments described below.

[0055] 8 is a cross-sectional view showing yet another embodiment of the waterproof outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to FIG. 2 to FIG. 6, so that the overlapping description will be omitted. The waterproof outer bearing device 43 includes a vent pipe 73 connected to the outer bearing cover 53 and a float valve 102 connected to the vent pipe 73. The inlet of the float valve 102 faces downward. The vent pipe 73 communicates with the space Q between the outer bearing cover 53 and the inner bearing cover 52, and the space Q communicates with the bearing chamber 50 through a through hole 74 formed in the inner bearing cover 52.

[0056] 9 is an enlarged cross-sectional view of one embodiment of the float valve 102. The float valve 102 is configured to close when the water level is higher than the float valve 102 and open when the water level is lower than the float valve 102. The float valve 102 has a ball housing 104 connected to the vent pipe 73 and a ball valve 103 disposed in the ball housing 104. The ball valve 103 can move up and down in the ball housing 104. During normal operation of the vertical pump 1, the ball valve 103 is located at the bottom of the ball housing 104 due to gravity, and the float valve 102 is in an open state. The vent pipe 73 is in communication with the atmosphere through the float valve 102.

[0057] When the flood level rises due to a typhoon, heavy rain, or the like, the ball valve 103 rises within the ball housing 104 due to buoyancy, blocking the vent pipe 73. The float valve 102 is therefore closed, preventing water from flowing into the vent pipe 73. The specific configuration of the float valve 102 is not limited to the embodiment described with reference to Fig. 9, and any configuration may be used as long as the float valve 102 has a structure that closes due to buoyancy.

[0058] Fig. 10 is a cross-sectional view showing yet another embodiment of the waterproof outer bearing device 43. The configuration and operation of this embodiment that are not particularly described are the same as those of the embodiment described with reference to Figs. 2 to 6, so duplicated descriptions will be omitted. The waterproof outer bearing device 43 is equipped with an upper seal positioning device 110 that switches the position of the upper seal 81 between a contact position where the upper seal 81 contacts the outer peripheral surface 15a of the rotating shaft 15 and a non-contact position where the upper seal 81 is separated from the outer peripheral surface 15b of the rotating shaft 15. The outer peripheral surface 15b has a smaller diameter than the outer peripheral surface 15a.

[0059] The upper seal positioning device 110 includes an upper seal holder 111 that holds the upper seal 81, a bolt 113 fixed to the upper wall of the outer bearing cover 53, and a plurality of nuts (two nuts in FIG. 10) 115, 116 screwed onto the bolt 113. An O-ring 117 is attached to the bottom surface of the upper seal holder 111. The O-ring 117 extends so as to surround the rotating shaft 15. The bolt 113 extends upward from the outer bearing cover 53 and is parallel to the rotating shaft 15. The upper seal 81 is held on the inner peripheral surface of the upper seal holder 111. The bolt 113 extends through the upper seal holder 111, and the upper seal holder 111 is sandwiched between a plurality of nuts 115, 116. Therefore, the vertical positions of the upper seal 81 and the upper seal holder 111 are fixed by these nuts 115, 116. These nuts 115 and 116 screwed onto the bolt 113 function to determine the position of the upper seal holder 111 in the vertical direction.

[0060] In FIG. 10, the upper seal 81 is in a non-contact position facing the outer peripheral surface 15b of the rotating shaft 15, and the upper seal 81 is separated from the outer peripheral surface 15b (i.e., not in contact with the outer peripheral surface 15b). FIG. 11 is a diagram showing a state in which the upper seal 81 and the upper seal holder 111 are moved from the non-contact position shown in FIG. 10 to a contact position in which the upper seal 81 contacts the outer peripheral surface 15a of the rotating shaft 15. As shown in FIG. 11, the nut 116 below the upper seal holder 111 is removed from the bolt 113, and the nut 115 above the upper seal holder 111 is tightened, whereby the upper seal holder 111 is pressed against the upper wall of the outer bearing cover 53, and the upper seal 81 contacts the outer peripheral surface 15a of the rotating shaft 15. The vertical positions of the upper seal 81 and the upper seal holder 111 are fixed by the upper nut 115. An O-ring 117 arranged on the bottom surface of upper seal holder 111 contacts the upper wall of outer bearing cover 53 , so that the gap between upper seal holder 111 and outer bearing cover 53 is sealed by O-ring 117 .

[0061] According to the embodiment described with reference to Figures 10 and 11, during normal operation, the upper seal 81 is in the non-contact position shown in Figure 10, and when a rise in the flood level is expected due to a typhoon, heavy rain, or the like, the upper seal 81 is moved to the contact position shown in Figure 11. Since the upper seal 81 comes into contact with the rotating shaft 15 only in an emergency, wear of the upper seal 81 can be prevented and the life of the upper seal 81 can be extended.

[0062] A lower seal positioning device 120 having a configuration similar to that of the upper seal positioning device 110 described with reference to Figures 10 and 11 may also be applied to the lower seal 82. Figures 12 and 13 are views showing an embodiment of the lower seal positioning device 120 that switches the position of the lower seal 82 between a contact position where the lower seal 82 contacts the outer circumferential surface 15c of the rotating shaft 15 and a non-contact position where the lower seal 82 is separated from the outer circumferential surface 15d of the rotating shaft 15. The outer circumferential surface 15d has a smaller diameter than the outer circumferential surface 15c.

[0063] In FIG. 12, the lower seal positioning device 120 includes a lower seal holder 121 that holds the lower seal 82, a bolt 123 fixed to the lower wall of the bearing housing 51, and a plurality of nuts (two nuts in FIG. 12) 125, 126 screwed onto the bolt 123. An O-ring 127 is attached to the upper surface of the lower seal holder 121. The O-ring 127 extends so as to surround the rotating shaft 15. The bolt 123 extends downward from the lower wall of the bearing housing 51 and is parallel to the rotating shaft 15. The lower seal 82 is held on the inner peripheral surface of the lower seal holder 121. The bolt 123 extends through the lower seal holder 121, and the lower seal holder 121 is sandwiched between the plurality of nuts 125, 126. Therefore, the vertical positions of the lower seal 82 and the lower seal holder 121 are fixed by these nuts 125, 126. These nuts 125 and 126 screwed onto the bolt 123 function to position the lower seal holder 121 in the vertical direction.

[0064] In FIG. 12, the lower seal 82 is in a non-contact position facing the outer peripheral surface 15d of the rotating shaft 15, and the lower seal 82 is separated from the outer peripheral surface 15d (i.e., not in contact with the outer peripheral surface 15d). FIG. 13 is a diagram showing a state in which the lower seal 82 and the lower seal holder 121 are moved from the non-contact position shown in FIG. 12 to a contact position in which the lower seal 82 contacts the outer peripheral surface 15c of the rotating shaft 15. As shown in FIG. 13, the nut 125 on the lower seal holder 121 is removed from the bolt 123, and the nut 126 on the lower seal holder 121 is tightened, whereby the lower seal holder 121 is pressed against the lower wall of the bearing housing 51, and the lower seal 82 contacts the outer peripheral surface 15c of the rotating shaft 15. The vertical positions of the lower seal 82 and the lower seal holder 121 are fixed by the lower nut 126. An O-ring 127 arranged on the upper surface of lower seal holder 121 comes into contact with the bottom surface of bearing housing 51 , so that the gap between lower seal holder 121 and bearing housing 51 is sealed by O-ring 127 .

[0065] Fig. 14 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to Figs. 10 and 11, so the overlapping description will be omitted. In the upper seal positioning device 110 of the embodiment shown in Fig. 14, a spacer 130 is used instead of the nut 116 on the lower side of the upper seal holder 111 shown in Fig. 10. The bolt 113 extends through the spacer 130, and the spacer 130 is sandwiched between the upper wall of the outer bearing cover 53 and the upper seal holder 111.

[0066] In FIG. 14, the upper seal 81 is in a non-contact position facing the outer peripheral surface 15b of the rotating shaft 15, and the upper seal 81 is separated from the outer peripheral surface 15b (i.e., not in contact with the outer peripheral surface 15b). FIG. 15 is a diagram showing a state in which the upper seal 81 and the upper seal holder 111 are moved from the non-contact position shown in FIG. 14 to a contact position in which the upper seal 81 contacts the outer peripheral surface 15a of the rotating shaft 15. As shown in FIG. 15, the spacer 130 below the upper seal holder 111 is removed from the bolt 113, and the nut 115 above the upper seal holder 111 is tightened, whereby the upper seal holder 111 is pressed against the upper wall of the outer bearing cover 53, and the upper seal 81 contacts the outer peripheral surface 15a of the rotating shaft 15. The vertical positions of the upper seal 81 and the upper seal holder 111 are fixed by the upper nut 115. An O-ring 117 arranged on the bottom surface of upper seal holder 111 contacts the upper wall of outer bearing cover 53 , so that the gap between upper seal holder 111 and outer bearing cover 53 is sealed by O-ring 117 .

[0067] 16(a) to 16(c) are plan views showing some examples of the spacer 130. The spacer 130 shown in FIG. 16(a) has a plurality of through holes 131 through which the plurality of bolts 113 shown in FIG. 14 penetrate. The spacer 130 shown in FIG. 16(b) and FIG. 16(c) has a plurality of notches 132 through which the plurality of bolts 113 penetrate. Furthermore, the spacer 130 shown in FIG. 16(b) is divided into a plurality of parts 130A, 130B, 130C, and 130D, and the spacer 130 shown in FIG. 16(c) is divided into a plurality of parts 130E and 130F. Therefore, the spacer 130 can be removed from the bolt 113 simply by loosening the nut 115 shown in FIG. 14.

[0068] The lower seal positioning device 120 having the same configuration as the upper seal positioning device 110 described with reference to Figs. 14 to 16 may also be applied to the lower seal 82. Figs. 17 and 18 are views showing an embodiment of the lower seal positioning device 120 that switches the position of the lower seal 82 between a contact position where the lower seal 82 contacts the outer peripheral surface 15c of the rotating shaft 15 and a non-contact position where the lower seal 82 is separated from the outer peripheral surface 15d of the rotating shaft 15. The configuration and operation of this embodiment that are not particularly described are the same as those of the embodiment described with reference to Figs. 12 and 13, so that redundant description will be omitted. The outer peripheral surface 15d has a smaller diameter than the outer peripheral surface 15c. The spacer 140 is sandwiched between the lower wall of the bearing housing 51 and the lower seal holder 121. The spacer 140 may have the same configuration as the spacer 140 described with reference to Figs. 14 to 16.

[0069] In FIG. 17, the lower seal 82 is in a non-contact position facing the outer peripheral surface 15d of the rotating shaft 15, and the lower seal 82 is separated from the outer peripheral surface 15d (i.e., not in contact with the outer peripheral surface 15d). FIG. 18 is a diagram showing a state in which the lower seal 82 and the lower seal holder 121 shown in FIG. 17 are moved from the non-contact position shown in FIG. 17 to a contact position in which the lower seal 82 contacts the outer peripheral surface 15c of the rotating shaft 15. As shown in FIG. 18, the spacer 140 on the lower seal holder 121 is removed from the bolt 123, and the nut 126 below the lower seal holder 121 is tightened, whereby the lower seal holder 121 is pressed against the lower wall of the bearing housing 51, and the lower seal 82 contacts the outer peripheral surface 15c of the rotating shaft 15. The vertical positions of the lower seal 82 and the lower seal holder 121 are fixed by the lower nut 126. An O-ring 127 arranged on the upper surface of lower seal holder 121 comes into contact with the bottom surface of bearing housing 51 , so that the gap between lower seal holder 121 and bearing housing 51 is sealed by O-ring 127 .

[0070] Fig. 19 is a cross-sectional view showing yet another embodiment of the waterproof outer bearing device 43. The configuration and operation of this embodiment that are not particularly described are the same as those of the embodiment described with reference to Figs. 10 and 11, so that the overlapping description will be omitted. The waterproof outer bearing device 43 includes a plurality of spare upper seals 145 and a plurality of spare upper seal holders 146 arranged above the upper seal 81 and the upper seal holder 111, and an upper seal storage container 147 in which the plurality of spare upper seals 145 and the plurality of spare upper seal holders 146 are accommodated. Each of the plurality of spare upper seals 145 has the same structure as the upper seal 81, and each of the plurality of spare upper seal holders 146 has the same structure as the upper seal holder 111.

[0071] The upper seal storage container 147 is fixed to the outer bearing cover 53 by a bracket 148. In another example, the upper seal storage container 147 may be fixed to a coupling cover (not shown). The spare upper seals 145 and the spare upper seal holders 146 are stored in the upper seal storage container 147 with the rotating shaft 15 passing through. An O-ring 149 is attached to the upper surface of the outer bearing cover 53. The O-ring 149 is disposed at a position facing the bottom surface of the upper seal holder 111. The O-ring 149 extends to surround the rotating shaft 15. No O-ring is attached to the upper seal holder 111 and the spare upper seal holder 146.

[0072] When the upper seal 81 is worn down and reaches the end of its life, the upper seal 81 and the upper seal holder 111 are disassembled and removed from the water-resistant outer bearing device 43. Next, one of the multiple spare upper seals 145 and one of the multiple spare upper seal holders 146 stored in the upper seal storage container 147 are lowered and held by the upper seal positioning device 110. More specifically, the spare upper seal 145 and the spare upper seal holder 146 are held by the nuts 115, 116 and the bolts 113. In an emergency in which the flood level has risen, the spare upper seal 145 and the spare upper seal holder 146 are moved to the contact position to bring the spare upper seal 145 into contact with the outer circumferential surface 15a of the rotating shaft 15, as described with reference to FIG. 11. The bottom surface of the spare upper seal holder 146 comes into contact with an O-ring 149 attached to the upper surface of the outer bearing cover 53 , thereby sealing the gap between the outer bearing cover 53 and the spare upper seal holder 146 .

[0073] According to this embodiment, when the upper seal 81 wears out and reaches the end of its life, the worn upper seal 81 can be replaced with a new upper seal without disassembling the water-resistant outer bearing device 43. The number of spare upper seals 145 and the number of spare upper seal holders 146 are not limited to the embodiment shown in Fig. 19. For example, one spare upper seal 145 and one spare upper seal holder 146 may be stored in the upper seal storage container 147.

[0074] 20 , the water-resistant outer bearing device 43 may include a plurality of spare lower seals 151 and a plurality of spare lower seal holders 152 arranged below the lower seal 82 and the lower seal holder 121, and a lower seal storage container 153 in which the plurality of spare lower seals 151 and the plurality of spare lower seal holders 152 are housed. The lower seal storage container 153 is fixed to the bearing housing 51 by a bracket 154. Each of the plurality of spare lower seals 151 has the same structure as the lower seal 82, and each of the plurality of spare lower seal holders 152 has the same structure as the lower seal holder 121.

[0075] An O-ring 155 is attached to the bottom surface of bearing housing 51. O-ring 155 is disposed in a position facing the upper surface of lower seal holder 121. O-ring 155 extends so as to surround rotating shaft 15. No O-ring is attached to lower seal holder 121 and spare lower seal holder 152.

[0076] As in the embodiment of FIG. 19, when the lower seal 82 wears out and reaches the end of its life, the lower seal 82 and the lower seal holder 121 are disassembled and removed from the water-resistant outer bearing device 43. Next, one of the multiple spare lower seals 151 and one of the multiple spare lower seal holders 152 stored in the lower seal storage container 153 are raised and held by the lower seal positioning device 120. As described with reference to FIG. 13, the spare lower seal 151 comes into contact with the outer circumferential surface 15c of the rotating shaft 15. The upper surface of the spare lower seal holder 152 comes into contact with the O-ring 155 attached to the bottom surface of the bearing housing 51, thereby sealing the gap between the bearing housing 51 and the spare lower seal holder 152.

[0077] According to this embodiment, when the lower seal 82 wears out and reaches the end of its life, the worn lower seal 82 can be replaced with a new lower seal without disassembling the water-resistant outer bearing device 43. The number of spare lower seals 151 and the number of spare lower seal holders 152 are not limited to the embodiment shown in Fig. 20. For example, one spare lower seal 151 and one spare lower seal holder 152 may be stored in the lower seal storage container 153.

[0078] Fig. 21 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to Figs. 10 and 11, and therefore the duplicated description will be omitted. The water-resistant outer bearing device 43 is provided with an upper movable sleeve 160 having an inner peripheral threaded portion 162 that is screwed into an outer peripheral threaded portion 161 formed on the outer peripheral surface of the rotating shaft 15. The upper movable sleeve 160 has a cylindrical shape and a smooth outer peripheral surface.

[0079] The upper movable sleeve 160 is movable on the rotating shaft 15 between a contact position where it contacts the upper seal 81 and a non-contact position where it is separated from the upper seal 81. More specifically, in the non-contact position shown in FIG. 21 , the upper movable sleeve 160 is located higher than the upper seal 81 and is not in contact with the upper seal 81. The upper seal 81 does not contact the outer circumferential surface of the rotating shaft 15. In other words, the inner diameter of the upper seal 81 is larger than the diameter of the rotating shaft 15.

[0080] 22, when the upper movable sleeve 160 is rotated, the upper movable sleeve 160 descends to the contact position, and the upper seal 81 comes into contact with the outer peripheral surface of the upper movable sleeve 160. As a result, the gap between the outer bearing cover 53 and the outer peripheral surface of the rotating shaft 15 is sealed by the upper seal 81 and the upper movable sleeve 160.

[0081] According to the embodiment described with reference to Figures 21 and 22, during normal operation of the vertical pump 1, the upper movable sleeve 160 is in the non-contact position shown in Figure 21, and when a rise in the flood level is expected due to a typhoon, heavy rain, or the like, the upper movable sleeve 160 is moved to the contact position shown in Figure 22. Since the upper seal 81 comes into contact with the upper movable sleeve 160 only in an emergency, wear on the upper seal 81 can be prevented and the life of the upper seal 81 can be extended.

[0082] As shown in FIG. 23, the water-resistant outer bearing device 43 may include a lower movable sleeve 170 having an inner peripheral thread portion 172 screwed into an outer peripheral thread portion 171 formed on the outer peripheral surface of the rotating shaft 15. The lower movable sleeve 170 has a cylindrical shape and a smooth outer peripheral surface. The lower seal 82 is held by a lower seal holder 173 fixed to the lower wall of the bearing housing 51. An O-ring 174 is disposed between the bottom surface of the bearing housing 51 and the lower seal holder 173. In the embodiment shown in FIG. 23, the O-ring 174 is disposed on the upper surface of the lower seal holder 173. In one embodiment, the O-ring 174 may be disposed on the bottom surface of the bearing housing 51.

[0083] The lower movable sleeve 170 is movable on the rotating shaft 15 between a contact position where it contacts the lower seal 82 and a non-contact position where it is separated from the lower seal 82. More specifically, in the non-contact position shown in FIG. 23 , the lower movable sleeve 170 is located lower than the lower seal 82 and is not in contact with the lower seal 82. The lower seal 82 does not contact the outer circumferential surface of the rotating shaft 15. In other words, the inner diameter of the lower seal 82 is larger than the diameter of the rotating shaft 15.

[0084] 24, when the lower movable sleeve 170 is rotated, the lower movable sleeve 170 rises to the contact position, and the lower seal 82 comes into contact with the outer circumferential surface of the lower movable sleeve 170. As a result, the gap between the bearing housing 51 and the outer circumferential surface of the rotating shaft 15 is sealed by the lower seal 82 and the lower movable sleeve 170.

[0085] Fig. 25 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to Figs. 2 to 6, and therefore the overlapping description will be omitted. The upper seal 81 of this embodiment is a magnetic fluid seal having an electromagnet 181 that forms a magnetic field and a magnetic fluid 182 disposed within the magnetic field. The electromagnet 181 is connected to a power supply device (not shown). The magnetic fluid 182 has an annular shape extending around the rotating shaft 15.

[0086] An O-ring 183 is disposed between the upper seal 81 and the outer bearing cover 53. The O-ring 183 extends so as to surround the rotating shaft 15. The gap between the outer bearing cover 53 and the upper seal 81 is sealed by the O-ring 183. In the embodiment shown in FIG. 25 , the O-ring 183 is disposed on the upper surface of the outer bearing cover 53. In one embodiment, the O-ring 183 may be disposed on the lower surface of the upper seal 81.

[0087] During normal operation of the vertical pump 1, no power is supplied to the electromagnet 181, and the magnetic fluid 182 is not in contact with the rotating shaft 15. When a rise in the flood level is expected due to a typhoon, heavy rain, or the like, power is supplied from a power supply device to the electromagnet 181. The electromagnet 181 forms a magnetic field, and the magnetic fluid 182 is deformed within the magnetic field. As a result, the magnetic fluid 182 comes into contact with the outer peripheral surface of the rotating shaft 15, forming a seal between the outer bearing cover 53 and the rotating shaft 15.

[0088] Similarly, the lower seal 82 is a magnetic fluid seal having an electromagnet 184 that forms a magnetic field and a magnetic fluid 185 disposed within the magnetic field. The electromagnet 184 is connected to the power supply device. The magnetic fluid 185 has an annular shape that extends around the rotating shaft 15. An O-ring 186 is disposed between the lower seal 82 and the bottom surface of the bearing housing 51. The O-ring 186 extends so as to surround the rotating shaft 15. The gap between the bottom surface of the bearing housing 51 and the lower seal 82 is sealed by the O-ring 186. In the embodiment shown in FIG. 25, the O-ring 186 is disposed on the bottom surface of the bearing housing 51. In one embodiment, the O-ring 186 may be disposed on the upper surface of the lower seal 82.

[0089] During normal operation of the vertical pump 1, no power is supplied to the electromagnet 184, and the magnetic fluid 185 is not in contact with the rotating shaft 15. When a rise in the flood level is expected due to a typhoon, heavy rain, or the like, power is supplied from the power supply device to the electromagnet 184. As a result, the magnetic fluid 185 comes into contact with the outer circumferential surface of the rotating shaft 15, forming a seal between the bearing housing 51 and the rotating shaft 15.

[0090] FIG. 26 is a cross-sectional view showing yet another embodiment of the waterproof outer bearing device 43. The configuration and operation of this embodiment that are not particularly described are the same as those of the embodiment described with reference to FIG. 2 to FIG. 6, so that the overlapping description will be omitted. The upper seal 81 of this embodiment is a gas expansion seal including a balloon ring 191 that can contact the rotating shaft 15 and separate from the rotating shaft 15, and a balloon housing 192 that houses the balloon ring 191 therein. The balloon ring 191 is connected to a gas supply device (not shown). The balloon ring 191 has an annular shape that extends around the rotating shaft 15.

[0091] An O-ring 193 is disposed between the upper seal 81 and the outer bearing cover 53. The O-ring 193 extends so as to surround the rotating shaft 15. The gap between the outer bearing cover 53 and the upper seal 81 is sealed by the O-ring 193. In the embodiment shown in FIG. 26 , the O-ring 193 is disposed on the upper surface of the outer bearing cover 53. In one embodiment, the O-ring 193 may be disposed on the lower surface of the upper seal 81.

[0092] During normal operation of the vertical pump 1, no gas is supplied to the balloon ring 191, and the balloon ring 191 is not in contact with the rotating shaft 15. When a rise in the flood level is expected due to a typhoon, heavy rain, or the like, gas is supplied from the gas supply device to the balloon ring 191, and the balloon ring 191 expands, as shown in Fig. 27. As a result, the balloon ring 191 comes into contact with the outer peripheral surface of the rotating shaft 15, and forms a seal between the outer bearing cover 53 and the rotating shaft 15.

[0093] 28, the lower seal 82 is a gas expansion seal including a balloon ring 195 that can contact the rotating shaft 15 and move away from the rotating shaft 15, and a balloon housing 196 that houses the balloon ring 195. The balloon ring 195 is connected to the gas supply device. The balloon ring 195 has an annular shape that extends around the rotating shaft 15.

[0094] An O-ring 197 is disposed between the lower seal 82 and the bottom surface of the bearing housing 51. The O-ring 197 extends so as to surround the rotating shaft 15. The gap between the bottom surface of the bearing housing 51 and the lower seal 82 is sealed by the O-ring 197. In the embodiment shown in FIG. 28 , the O-ring 197 is disposed on the bottom surface of the bearing housing 51, but in one embodiment, the O-ring 197 may be disposed on the upper surface of the lower seal 82.

[0095] During normal operation of the vertical pump 1, no gas is supplied to the balloon ring 195, and the balloon ring 195 is not in contact with the rotating shaft 15. When a rise in the flood level is expected due to a typhoon, heavy rain, or the like, gas is supplied from the gas supply device to the balloon ring 195, and the balloon ring 195 expands, as shown in Fig. 29. As a result, the balloon ring 195 comes into contact with the outer circumferential surface of the rotating shaft 15, and forms a seal between the bearing housing 51 and the rotating shaft 15.

[0096] Figure 30 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment that are not specifically described are the same as those of the embodiment described with reference to Figures 2 to 6, and therefore the duplicated description will be omitted. In this embodiment, an upper seal 81 is not provided. Also, an outer bearing cover 53 is not provided. In the embodiment described below, the inner bearing cover 52 is simply referred to as the bearing cover 52.

[0097] The water-resistant outer bearing device 43 includes a nut cover 200 that accommodates the adjustment nut 60, a seal 201 for sealing the gap between the bearing cover 52 and the outer peripheral surface of the journal 62, a seal 202 for sealing the gap between the nut cover 200 and the outer peripheral surface of the rotating shaft 15, and a seal 203 for sealing the gap between the nut cover 200 and the journal 62.

[0098] The adjusting nut 60 is screwed into a threaded portion 64 formed on the outer circumferential surface of the rotating shaft 15. More specifically, an inner threaded portion 65 of the adjusting nut 60 is screwed into the threaded portion 64 of the rotating shaft 15. The upper surface of the journal 62 is located above the bearing cover 52, and the lower portion of the journal 62 is located below the bearing cover 52 and within the bearing chamber 50. The journal 62 is rotatably supported by the bearings 47 and 48 within the bearing chamber 50.

[0099] The configuration of the seal 201 is not particularly limited, but for example, the seal 201 may be a sliding seal having a cross-sectional shape that opens to the outside to receive water pressure, as described with reference to Figures 3 and 4. The seal 201 can prevent water from flowing in through the gap between the bearing cover 52 and the outer circumferential surface of the journal 62 when the flood level rises due to a typhoon, heavy rain, or the like.

[0100] The seal 202 and the seal 203 are held by the nut cover 200. The nut cover 200, the adjusting nut 60, the seal 202, and the seal 203 rotate integrally with the rotating shaft 15. An example of the seal 202 and the seal 203 is an O-ring. The nut cover 200 is disposed on the upper surface of the journal 62, and surrounds the entire adjusting nut 60. The seal 202 is disposed between the inner peripheral surface of the nut cover 200 and the outer peripheral surface of the rotating shaft 15, and seals the gap between the inner peripheral surface of the nut cover 200 and the outer peripheral surface of the rotating shaft 15. The seal 203 is disposed between the lower surface of the nut cover 200 and the upper surface of the journal 62, and seals the gap between the lower surface of the nut cover 200 and the upper surface of the journal 62. The nut cover 200 itself has a structure that does not allow the flow of fluid (i.e., a structure without holes). Therefore, a sealed space is formed inside the nut cover 200, and the adjusting nut 60 is disposed in this sealed space.

[0101] Even if the flood level rises due to a typhoon or heavy rain, water will not reach the sealed space inside the nut cover 200. Therefore, water will not come into contact with the adjusting nut 60, and further water will not enter through the gap between the adjusting nut 60 and the rotating shaft 15, or the gap between the journal 62 and the rotating shaft 15.

[0102] The vent pipe 73 is detachably connected to the outer circumferential surface of the journal 62. The vent pipe 73 communicates with the air vent passage 70. The vent pipe 73 is detached during normal operation of the vertical shaft pump 1. Therefore, air flows in and out through the air vent passage 70 during operation of the vertical shaft pump 1. When the flood level is expected to rise due to a typhoon or heavy rain, the rotation of the rotating shaft 15 is stopped and the vent pipe 73 is attached to the outer circumferential surface of the journal 62. The vent pipe 73 extends upward to a position higher than the coupling 35, and may extend upward to a position higher than the installation floor 8 on which the driving source 7 shown in FIG. 1 is installed, for example. Therefore, even if the entire water-resistant outer bearing device 43 is submerged, water will not flow into the space Q and the bearing chamber 50 through the vent pipe 73.

[0103] FIG. 31 is a cross-sectional view showing another embodiment of the nut cover 200 and the adjustment nut 60. The configuration and operation of this embodiment that are not particularly described are the same as those of the embodiment described with reference to FIG. 30, so the overlapping description will be omitted. The nut cover 200 is removably fixed to the journal 62 by a screw 220. In this embodiment, the nut cover 200 is removably fixed to the journal 62 by a plurality of screws 220. More specifically, the nut cover 200 has a flange 222 that contacts the upper surface of the journal 62, and the flange 222 is formed with a plurality of through holes (not shown) through which the plurality of screws 220 can pass. The plurality of screws 220 are screwed into screw holes 223 formed in the journal 62 through the flange 222.

[0104] When the screws 220 are tightened, the nut cover 200 is secured to the top surface of the journal 62, pressing the seal 203 against the top surface of the journal 62. When the screws 220 are removed, the nut cover 200 can be lifted off the journal 62.

[0105] Figure 32 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment that are not specifically described are the same as those of the embodiment described with reference to Figures 2 to 6, and therefore the duplicated description will be omitted. In this embodiment, the upper seal 81 is not provided either. Furthermore, the outer bearing cover 53 is not provided. In the embodiment described below, the inner bearing cover 52 is simply referred to as the bearing cover 52.

[0106] 32, the waterproof outer bearing device 43 includes a seal holder 230 in contact with the upper surface of the journal 62, a seal 201 for sealing the gap between the bearing cover 52 and the outer circumferential surface of the journal 62, a seal 232 for sealing the gap between the seal holder 230 and the outer circumferential surface of the rotating shaft 15, and a seal 233 for sealing the gap between the seal holder 230 and the upper surface of the journal 62. The upper surface of the journal 62 is located above the bearing cover 52, and the lower part of the journal 62 is located below the bearing cover 52 and within the bearing chamber 50. The journal 62 is rotatably supported by bearings 47 and 48 within the bearing chamber 50.

[0107] Seal holder 230 has a shape that surrounds the outer circumferential surface of rotating shaft 15. Rotating shaft 15 extends through seal holder 230. Seal 232 and seal 233 are held in seal holder 230. Seal 232 is disposed on the inner circumferential surface of seal holder 230, and seal 233 is disposed on the bottom surface of seal holder 230.

[0108] The seal holder 230 not only holds the seal 232 and the seal 233, but also functions as an adjusting nut (see reference symbol 60) in the embodiments described so far. That is, the seal holder 230 as an adjusting nut has an inner threaded portion 235 that is screwed into a threaded portion 64 formed on the outer circumferential surface of the rotating shaft 15. By rotating the seal holder 230, the rotating shaft 15 can be moved up and down relative to the entire water-resistant outer bearing device 43. The seal holder 230 as an adjusting nut achieves the vertical positioning of the rotating shaft 15 with respect to the water-resistant outer bearing device 43.

[0109] The configuration of the seal 201 is not particularly limited, but for example, the seal 201 may be a sliding seal having a cross-sectional shape that opens outward to receive water pressure, as described with reference to Figs. 3 and 4. The seal 201 can prevent water from flowing in through the gap between the bearing cover 52 and the outer circumferential surface of the journal 62 when the flood level rises due to a typhoon, heavy rain, or the like. The seal holder (adjusting nut) 230, the seal 232, and the seal 233 rotate integrally with the rotating shaft 15. An example of the seal 232 and the seal 233 is an O-ring.

[0110] Seal 232 seals the gap between seal holder (adjusting nut) 230 and the outer circumferential surface of rotating shaft 15, and seal 233 seals the gap between seal holder (adjusting nut) 230 and the upper surface of journal 62. Therefore, even if the flood level rises due to a typhoon or heavy rain, water will not enter through the gap between seal holder (adjusting nut) 230 and rotating shaft 15, and the gap between journal 62 and rotating shaft 15.

[0111] The vent pipe 73 is detachably connected to the outer circumferential surface of the journal 62. The vent pipe 73 communicates with the air vent passage 70. The vent pipe 73 is detached during normal operation of the vertical shaft pump 1. Therefore, air flows in and out through the air vent passage 70 during operation of the vertical shaft pump 1. When the flood level is expected to rise due to a typhoon or heavy rain, the rotation of the rotating shaft 15 is stopped and the vent pipe 73 is attached to the outer circumferential surface of the journal 62. The vent pipe 73 extends upward to a position higher than the coupling 35, and may extend upward to a position higher than the installation floor 8 on which the driving source 7 shown in FIG. 1 is installed, for example. Therefore, even if the entire water-resistant outer bearing device 43 is submerged, water will not flow into the space Q and the bearing chamber 50 through the vent pipe 73.

[0112] Fig. 33 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to Fig. 32, and therefore the overlapping descriptions will be omitted. In this embodiment, the seal holder 230 and the adjusting nut 60 are provided as separate elements. That is, as shown in Fig. 33, the adjusting nut 60 and the seal holder 230 are arranged in series. The adjusting nut 60 is disposed above the seal holder 230.

[0113] Seal 232 is disposed on the inner circumferential surface of seal holder 230, and seal 233 is disposed on the bottom surface of seal holder 230. Seal holder 230 has a function of holding seal 232 and seal 233, and is not screwed into threaded portion 64 of rotating shaft 15. Adjusting nut 60 has an inner threaded portion 65 that screws into threaded portion 64 of rotating shaft 15, similar to the above-described embodiment.

[0114] Seal 201 seals the gap between bearing cover 52 and the outer circumferential surface of journal 62. Therefore, even if the flood level rises due to a typhoon or heavy rain, water will not flow in through the gap between bearing cover 52 and the outer circumferential surface of journal 62. Seal 232 seals the gap between seal holder 230 and the outer circumferential surface of rotating shaft 15, and seal 233 seals the gap between seal holder 230 and the upper surface of journal 62. Therefore, even if the flood level rises due to a typhoon or heavy rain, water will not enter through the gap between seal holder 230 and rotating shaft 15 and the gap between journal 62 and rotating shaft 15.

[0115] Fig. 34 is a cross-sectional view showing yet another embodiment of the water-resistant outer bearing device 43. The configuration and operation of this embodiment not specifically described are the same as those of the embodiment described with reference to Fig. 33, and therefore the overlapping descriptions will be omitted.

[0116] The water-resistant outer bearing device 43 of this embodiment includes bearings 47 and 48 that rotatably support the rotating shaft 15, a bearing housing 51 having a bearing chamber 50 therein in which the bearings 47, 48 are accommodated, a bearing cover 52 that covers the bearing chamber 50, a journal 62 fixed to the outer peripheral surface of the rotating shaft 15, an adjusting nut 60 screwed into a threaded portion 64 formed on the outer peripheral surface of the rotating shaft 15, a coupling 35 that forms a sealed space U therein in which the adjusting nut 60 and the upper end 15e of the rotating shaft 15 are disposed, a seal 201 for sealing the gap between the bearing cover 52 and the outer peripheral surface of the journal 62, and a seal 240 for sealing the gap between the coupling 35 and the journal 62.

[0117] The coupling 35 is in contact with the upper surface of the journal 62, and the adjusting nut 60 is located above the journal 62. The coupling 35 has a lower coupling 35A connected to the rotating shaft 15, an upper coupling 35B connected to the driving source 7 shown in FIG. 1, and an intermediate coupling 35C arranged between the upper coupling 35B and the lower coupling 35A. The lower coupling 35A has a through hole 244 through which the rotating shaft 15 passes. The lower surface of the lower coupling 35A is in contact with the upper surface of the journal 62.

[0118] The upper coupling 35B and the intermediate coupling 35C are connected by bolts and nuts (not shown). The intermediate coupling 35C and the lower coupling 35A are also connected by bolts and nuts (not shown). The coupling 35 has a coupling seal 246 that seals the gap between the intermediate coupling 35C and the lower coupling 35A. An example of the coupling seal 246 is an O-ring.

[0119] The intermediate coupling 35C has an outer peripheral wall 251 and a ceiling wall 252, and the lower end of the outer peripheral wall 251 is in contact with the upper surface of the lower coupling 35A. The coupling seal 246 seals the gap between the lower end of the outer peripheral wall 251 and the lower coupling 35A. Therefore, a sealed space U sealed by the coupling seal 246 is formed between the intermediate coupling 35C and the lower coupling 35A.

[0120] The adjusting nut 60 is disposed in the sealed space U and is in contact with the upper surface of the lower coupling 35A. At least a portion of a threaded portion 64 formed on the outer circumferential surface of the rotating shaft 15 is located in the sealed space U. The adjusting nut 60 has an inner threaded portion 65 that is screwed into the threaded portion 64. The upper end 15e of the rotating shaft 15 is located in the sealed space U and is not in contact with the ceiling wall 252 of the intermediate coupling 35C.

[0121] When the adjusting nut 60 is rotated with the intermediate coupling 35C detached from the lower coupling 35A, the rotating shaft 15 moves up and down relative to the entire water-resistant outer bearing device 43. This adjusting nut 60 is provided for positioning the rotating shaft 15 in the up and down direction relative to the water-resistant outer bearing device 43, as in the previously described embodiment.

[0122] The seal 240 is sandwiched between the lower surface of the lower coupling 35A and the upper surface of the journal 62, and seals the gap between the lower surface of the lower coupling 35A and the upper surface of the journal 62.

[0123] Seal 201 for sealing the gap between bearing cover 52 and the outer circumferential surface of journal 62 can prevent water from entering bearing chamber 50 through the gap between bearing cover 52 and the outer circumferential surface of journal 62. Furthermore, seal 240 for sealing the gap between coupling 35 and journal 62, and coupling 35 which forms sealed space U therein in which adjusting nut 60 and upper end 15e of rotating shaft 15 are disposed can prevent water from entering bearing chamber 50 through the gap between journal 62 and rotating shaft 15 and the gap between adjusting nut 60 and rotating shaft 15.

[0124] The above-mentioned embodiments can be combined as appropriate. For example, the buffer tank 100 described with reference to Fig. 7 and the float valve 102 described with reference to Figs. 8 and 9 can be applied to other embodiments. In addition, the lower seal 82 and its associated structure described with reference to Figs. 5, 6, 12, 13, 17, 18, 20, 23, 24, 25, 28, 29, etc. may be applied to the embodiment described with reference to Figs. 30 to 34.

[0125] The above-described embodiments have been described for the purpose of enabling a person having ordinary skill in the art to practice the present invention. Various modifications of the above-described embodiments are naturally possible for a person skilled in the art, and the technical idea of ​​the present invention can be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is to be interpreted in the broadest scope according to the technical idea defined by the claims. [Explanation of symbols]

[0126] 1 Vertical pump 2. Suction tank 3 Pump installation floor 5 aperture 7. Power Source 8 Installation floor 10 Impeller 15 Rotational Axis 22 Suction bell mouth 22a Intake port 24 Discharge Bowl 25 Inner Bowl 27 Pump casing 28 Lift pipe 30 Discharge bent pipe 33 Mounting flange 34 Discharge piping 35 Coupling 35A Lower Coupling 35B Upper coupling 35C Intermediate coupling 37 Guide vane 41 Underwater bearings 43 Water-resistant outer bearing device 45 Inspection hatch 47,48 Bearings 50 Bearing chamber 51 Bearing housing 52 Inner bearing cover 53 Outer bearing cover 55 Storage Cave 57 Threaded part 58 Set ring nut 60 Adjustment nut 62 Journals 65 Internal thread 67 Oil cylinder 68 Seal holder 69 Seal 70 Air vent passage 71 Interior Space 73 Vent pipe 74 Through hole 81, 82, 83 Seal 86,87 Static seal 90,91 smooth surface 94 Fixed side member 95 Rotating member 96 Sealing Element 97 Spring 98 O-ring 100 Buffer Tank 102 Float valve 103 Ball valve 104 Ball housing 110 Upper seal positioning device 111 Upper seal holder 113 Volts 115,116 Nut 117 O-ring 120 Lower seal positioning device 121 Lower seal holder 123 Volts 125,126 Nut 127 O-ring 130 Spacer 131 Through hole 132 Notch 140 Spacer 145 Spare upper seal 146 Spare upper seal holder 147 Upper Seal Storage Container 148 Bracket 149 O-ring 151 Spare lower seal 152 Spare lower seal holder 153 Lower seal storage container 154 Bracket 155 O-ring 160 Upper movable sleeve 161 Outer thread 162 Internal thread 170 Lower movable sleeve 171 Outer thread 172 Internal thread 173 Lower seal holder 174 O-ring 181,184 Electromagnets 182,185 magnetic fluid 183 O-ring 186 O-ring 191,195 Balloon Ring 192,196 Balloon housing 193 O-ring 197 O-ring 200 Nut cover 201,202,203 Seal 206 Internal thread 210 Outer thread 212 Spacer 220 Screw 222 Flange 223 Screw hole 230 Seal holder 232,233 Seal 235 Internal thread 240 Seals 244 Through hole 246 Coupling seal 251 Outer wall 252 Ceiling Wall Q Space S closed space U-shaped sealing space

Claims

1. A water-resistant outer bearing device for supporting a rotating shaft of a vertical pump, a bearing that rotatably supports the rotating shaft; a bearing housing having a bearing chamber therein in which the bearing is accommodated; A bearing cover that covers the bearing chamber; a journal fixed to an outer circumferential surface of the rotating shaft; an adjustment nut contacting an upper surface of the journal; A nut cover that accommodates the adjustment nut; a first seal for sealing a gap between the bearing cover and an outer circumferential surface of the journal; A second seal for sealing a gap between the nut cover and an outer circumferential surface of the rotating shaft; a third seal for sealing a gap between the nut cover and the journal; The adjustment nut is screwed into a threaded portion formed on the outer circumferential surface of the rotating shaft, thereby forming a water-resistant outer bearing device.

2. 2. The water-resistant outer bearing device according to claim 1, wherein the nut cover is removably fixed to the journal by a screw.

3. a vent tube removably connected to the journal; 2. The water-resistant outer bearing device according to claim 1, wherein the ventilation pipe is connected to an air vent passage formed inside the journal.

4. The water-resistant outer bearing device according to claim 1 , further comprising a lower seal for sealing a gap between the bearing housing and the rotating shaft.

5. The lower seal is a fixed member fixed to the bearing housing; A rotating member fixed to the rotating shaft; 5. The water-resistant outer bearing device according to claim 4, further comprising a seal element supported by the fixed member and pressed against the rotating member.

Images