JP3686969B2 - Pump bearing device and pump device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to, for example, a bearing device that supports a pump main shaft of a vertical-axis rainwater drainage pump device installed in a drainage station, and a pump device that uses the bearing device.
[0002]
[Prior art]
Due to rapid urbanization in recent years, urban floods are more likely to occur in urban areas. In order to prevent such urban floods, construction of drainage stations that collect rainwater and drain it into rivers is underway.
[0003]
For example, as shown in FIG. 3, a vertical axis rainwater drainage pump device installed in a drainage station has been proposed. In the figure, a ceramic bearing 3 is supported at a predetermined position of the pump casing 1 via a casing flange portion 2. A sleeve 5 having at least a surface formed of cemented carbide is attached to the pump main shaft 4 at a position facing the bearing 3 and is rotatably supported by the bearing 3. A blade 6 is attached to the lower end of the pump main shaft 4.
[0004]
When the pump main shaft 4 is rotationally driven by a drive source (not shown), the blade 6 is rotated together with the pump main shaft 4 and pumped by the blade 6. Rainwater pumped up by the blades 6 rises in the pump casing 1 and is drained into the river.
[0005]
In the drainage station, when the area to be urbanized is expanded, the inflowing rainwater becomes abrupt and large in volume. Therefore, if the drainage pump is started after the inflow of rainwater, the inflowing rainwater However, the drainage pump may not be in time, and it is required to operate the drainage pump in advance standby. For this reason, normally, the bearing 3 supporting the pump main shaft is devised so as to reduce wear of the bearing and the pump main shaft during the preceding standby operation by using a ceramic bearing.
[0006]
However, during the pre-standby operation, it is in an air operation state in which rainwater is not pumped even if the pump spindle is rotating, and if this air operation state continues for a long time, abnormal wear of the bearing due to dry operation will occur. The occurrence of is inevitable.
[0007]
As means for solving such a problem, for example, in Japanese Patent Laid-Open No. 2-115592, lubricating air is supplied to the bearing portion from the outside of the drainage pump during the aerial operation period, and rainwater is supplied to the bearing portion by pumping up the pump. There has been proposed a lubrication method in which the supply of lubricating water is stopped when water is submerged.
[0008]
Japanese Laid-Open Patent Publication No. 59-155621 proposes that a bearing is formed of an oil-containing ceramic material and a small amount of oil that oozes out from the bearing is used as a lubricant.
[0009]
Further, Japanese Patent Application Laid-Open No. 55-90718 proposes that a protective pipe is provided on the pump main shaft, and the inside is used as a water reservoir to supply fresh water, and the bearing is lubricated with this fresh water.
Japanese Patent Application Laid-Open No. 6-94035 proposes a bearing device provided with a water storage tank so that the bearing portion is immersed in lubricating water.
[0010]
[Problems to be solved by the invention]
However, in the case of supplying lubricating water to the bearing portion, water must be poured into the bearing from the outside during the air operation, and a large amount of lubricating water is required when the air operation time becomes long. Moreover, since the water supply piping system is provided, maintenance management of the piping is required, and the burden for that is increased.
[0011]
Further, in the case of using the oil that oozes out from the bearing as the lubricant, the amount of oil contained in the bearing is small, so that the oil runs out, and when the air operation is repeated, the state becomes the same as the dry operation.
[0012]
Furthermore, water level management is required for structures that store water. In the case where the water reservoir is provided, maintenance management of the water supply piping system is required, and the burden for that is increased.
[0013]
In view of the above circumstances, an object of the present invention is to provide a pump bearing device and a pump device capable of repeatedly performing aerial operation in a stable state for a long period of time.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, in the first invention of the present application, a bearing that is disposed inside the pump casing via a bearing case and rotatably supports the pump spindle, and that surrounds the bearing case. In a pump bearing device comprising a liquid storage tank having a lower end fixed to the pump main shaft,
Non-volatile liquid is stored in the liquid storage tank ,
The non-volatile liquid has a specific gravity greater than that of the liquid pumped up by the pump and does not mix with the liquid pumped up by the pump.
[0015]
In the second invention of the present application, the non-volatile liquid in the first invention has lubricating characteristics.
[0016]
In the third invention of the present application, a liquid layer to be pumped up by a pump is provided on the non-volatile liquid in the first to second inventions.
[0017]
Furthermore, in the fourth invention of the present application, the pump main shaft is supported by the bearing device according to any one of the first to third inventions.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing a first embodiment of a bearing device for a pump according to the present invention.
[0019]
In the figure, 1 is a pump casing. A casing flange portion 2 is formed with a plurality of holes 2 a through which pumped liquid pumped by the pump is passed, and is fixed to the pump casing 1. A ceramic bearing 3 is fixed to the casing flange portion 2 via a bearing case 7. The bearing case 7 may be formed with a plurality of holes 7a radially.
[0020]
4 is a pump shaft. A sleeve 5 made of cemented carbide or coated with cemented carbide is fixed to the pump main shaft 4 so as to face the bearing 3. A liquid storage tank 8 is fixed to the pump main shaft 4 so as to surround the bearing 3. The upper end portion of the liquid storage tank 8 is bent in a U shape toward the bearing case 7 to prevent the liquid 9 supplied therein from being scattered due to the centrifugal force.
[0021]
The liquid 9 is non-volatile, has lubrication characteristics, has a specific gravity greater than that of a liquid pumped up by a pump (for example, rainwater), and does not mix with the liquid. Trifluoroethane can be used.
[0022]
In such a configuration, when the pump main shaft 4 is rotated, the liquid storage tank 8 and the liquid 9 are also rotated at the same time, and the centrifugal force causes the liquid 9 in the liquid storage tank 8 to circulate as indicated by the arrows. Since the bearing 3 is always immersed in the liquid 9, lubrication with the liquid 9 is performed, and a stable operation can be performed even in the air operation state during the preceding standby operation.
[0023]
Further, since the liquid 9 circulates in the liquid storage tank 8, even if heat is generated due to contact between the bearing 3 and the sleeve 5, the liquid 9 is cooled by the circulation of the liquid 9, and the temperature rise of the bearing 3 can be suppressed. It is possible to improve the load bearing characteristics. Furthermore, since the liquid 9 is non-volatile, the labor for management can be reduced.
[0024]
FIG. 2 is a cross-sectional view showing a second embodiment of the bearing device of the pump according to the present invention.
In the figure, the same components as those in FIG. 1 are denoted by the same reference numerals. 10 is a liquid that does not mix with the liquid 9 and has a specific gravity smaller than that of the liquid 9 (for example, water, a pumped liquid, or a liquid that has a higher specific gravity than the pumped liquid without mixing with the pumped liquid). .
[0025]
With such a configuration, it is possible to completely separate the pumping liquid and the liquid 9 flowing into the liquid storage tank 8 from the gap around the pump main shaft 4 during pumping. Regardless of the type of liquid, lubrication with the liquid 9 can be performed, and a stable operation can be performed.
[0026]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the bearings are always immersed in a non-volatile liquid, lubrication by the liquid is performed, the aerial operation state at the time of the prior standby operation even, it is possible to perform stable operation. Moreover, the management of the liquid can be facilitated. In addition, since the specific gravity of the non-volatile liquid is larger than the specific gravity of the liquid pumped up by the pump and does not mix with the liquid pumped up by the pump, it can be lubricated only by the non-volatile liquid. The reliability can be further improved.
[0028]
According to the second invention of the present application, since the non-volatile liquid is a liquid having a lubricating characteristic, the lubricating characteristic of the bearing portion can be improved.
[0029]
According to the third invention of the present application, since the liquid layer pumped up by the pump is provided on the non-volatile liquid, the pumped liquid is not mixed with the liquid supplied to the bearing portion. Furthermore, the lubrication characteristics of the bearing portion can be improved.
[0030]
Furthermore, according to the fourth aspect of the present invention, by supporting the bearing device according to the pump main shaft to one of claims 1 to 3, the reliability of the installed pump apparatus such as pumping stations Can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a pump bearing device according to the present invention.
FIG. 2 is a sectional view showing a second embodiment of a pump bearing device according to the present invention.
FIG. 3 is a sectional view showing an installation state of a pump device in a drainage station.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Pump casing, 3 ... Bearing, 4 ... Pump main shaft,
7 ... Bearing case, 8 ... Liquid storage tank, 9, 10 ... Liquid.

Claims (4)

A pump including a bearing disposed inside a pump casing via a bearing case and rotatably supporting the pump main shaft, and a liquid storage tank having a lower end fixed to the pump main shaft so as to surround the bearing case In the bearing device of
Non-volatile liquid is stored in the liquid storage tank ,
A pump bearing device , wherein the specific gravity of the non-volatile liquid is greater than the specific gravity of the liquid pumped up, and the liquid does not mix with the liquid pumped up by the pump. 2. The pump bearing device according to claim 1, wherein the non-volatile liquid is a liquid having a lubricating characteristic. Wherein on a non-volatile liquid, characterized in that a layer of liquid pumping in the pump, the bearing device of the pump according to claim 1 or claim 2. A pump device, wherein the pump main shaft is supported by the bearing device according to any one of claims 1 to 3 .

Images