JPS6116293A - Underwater bearing device in pump - Google Patents

Abstract

PURPOSE:To forcedly lubricate an underwater bearing to enhance the lubrication of the bearing, by determining the dimensions and shapes of two spatters such that a difference is effected between water pressures at both ends of the underwater bearing. CONSTITUTION:When spatters 11, 11' rotate in association with the rotation of a pump shaft 1, water between the spatters and a bearing support 7 creates a swirl stream under action of radial blades 11b, 11b' of the spatters. The dimentions of the radial blades 11b, 11b' are set such as Do>Do' in outer diameter, and Di=Di' in inner diameter, and therefore, the drop in static pressure around the underwater bearing, caused by the blades 11b is larger than that by the blades 11b', that is, PX<PY. Accordingly, due to a pressure differential between the points X, Y a stream passing through the underwater bearing from the point X to point Y is effected, thereby the bearing is forcedly lubricated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a submersible bearing for a pump that does not have a protection tube or external bearing water supply means.

[Background of the invention]

For example, as a means to prevent submerged bearings of pumps that do not have a protection pipe or external bearing water supply means from being worn out by foreign substances such as sand mixed in pumping water,
As shown in Japanese Patent No. 7-47796, sputters are provided on both sides of the underwater bearing, each fixed to a rotating shaft, and the rotational movement of the sputters scatters foreign matter such as sand in the water, thereby causing the connection between the underwater bearing and the sleeve. 2. Description of the Related Art A method is known that makes it possible to obtain lubricating water that does not contain foreign matter on sliding surfaces, thereby preventing underwater bearings from being worn out by foreign matter such as sand. That is, to explain with reference to FIG. 1, l is a pump shaft, 6 is an underwater bearing that supports the sleeve IO attached to the pump shaft 1, 7 is a bearing support that supports the underwater bearing 6, and 11 is a submersible bearing on both sides of the underwater bearing 6. The sputter 11 is composed of a disk 11a fixed to the rotation shaft 1, and radial blades 11b attached to both sides of the disk 11a.
As the sputter rotates together with the pump shaft, lubricating water that does not contain foreign matter is obtained as described above. In this example, there is no need for a protection tube or external bearing water supply means.
A simple device centrifuges foreign matter in the water pumped by the pump and obtains foreign matter-free bearing lubricating water, making it easy to apply to pumps that handle water containing sand, such as river water, rainwater, seawater, etc. This device has the advantage of extending the life of underwater bearings. However, this device does not consider providing such a forced lubrication effect. Therefore, the cooling effect against the frictional heat generated in the sliding parts of the underwater bearing and the rotating shaft is effective against the conventional water supply method (which has a protection tube and means for supplying lubricating water from the outside) that forcibly supplies lubricating water. Therefore, there was a problem that the bearing load and rotation speed could not be increased.

[Object of the Invention] The present invention is a submersible bearing installed in a pump body without a protection pipe or external bearing water supply means, and has spatter fixed to a rotating shaft on both sides of the bearing to prevent foreign matter from entering the water. The purpose of this invention is to forcibly supply lubricating water to the bearings, thereby improving the lubrication and cooling of the bearings.

[Summary of the invention]

The present invention focuses on the phenomenon that the water in the gap between the sputter and the underwater bearing rotates due to the rotation of the sputter, which causes a pressure drop from the outer circumference of the sputter toward the shaft side. The strength of the swirling flow is made different between the spatter on both sides of the bearing, which creates a difference in water pressure at both ends of the underwater bearing, and this pressure difference causes the sliding part between the underwater bearing and the shaft to It allows water to flow.

[Embodiments of the invention]

Hereinafter, FIG. 2 of the embodiment of the present invention will be explained.

In the figure, 1 is a pump shaft, 6 is an underwater bearing that supports the pump shaft, 7 is a bearing support that supports the underwater bearing 6, 11.1
1' is a sputter provided adjacent to both ends of the underwater bearing 6 and fixed to the rotating shaft, and this sputter 11.11
' denotes the disks 11a and lla' fixed to the rotating shaft 1, and this disk 11a.

It is composed of radial vanes 11b and llb' attached to the surface of 11a' facing the underwater bearing. And the outer diameter D of these two radial blades 11b and 11b'
0. D. ' are not equal to D.

＞　Do’.

When the sputter 11°11' rotates with the rotation of the pump shaft, its radial vane 11b.

11b' causes a swirling flow in the water between the sputter and the bearing support 7. Therefore, due to the action of the centrifugal force accompanying the swirling flow, foreign matter with a higher specific gravity than water, such as sand mixed in the water, is blown away to the outer circumferential side, and water with less foreign matter gathers on the shaft side and is supplied to the underwater bearing. . by the way,
It is known that when a swirling flow occurs, the static pressure is high on the outer circumferential side to maintain balance with the centrifugal force, and that the static pressure decreases at the small radius, and that the amount of decrease in static pressure is proportional to the square of the swirling speed. There is.

In the figure, the outer diameter of the radial blades 11b and 11b' is the same. >D. ' , inner radius, = D, ', so the static pressure drop at the underwater bearing due to the action of the radial vane is 1 l of the vane.
b is larger, and P,<R,y. Therefore, due to the difference in pressure between points X and Y, a flow is generated that passes through the underwater bearing from point Y to point X, and the bearing is forcibly lubricated.

Therefore, compared to when submersible bearings are used simply submerged in water, the lubrication and cooling of the bearings is improved, making them more reliable against seizure and damage, and allowing for higher bearing loads and rotational speeds. Can be used in

In addition, to change the strength of water swirl between the sputter and the underwater bearing support, in addition to changing the outer diameter of the radial vane as shown in the example in the figure, you can also change the inner diameter of the radial vane.

The number of blades (2), the blade height (h), etc. may be changed. Further, even if the sputter is not provided with radial vanes, a swirling flow is generated by the frictional force even if the sputter is provided with only a disk, so the sputter may be configured with only a disk.

〔Effect of the invention〕

As explained above, according to the present invention, lubricating water that does not contain foreign substances such as sand is obtained by the action of the sputter that rotates with the rotation of the pump shaft, and the bearing is forced by the differential pressure generated at both ends of the underwater bearing. The lubrication improves bearing lubrication and cooling compared to submerged bearings that are simply submerged in water, and prevents bearing seizure.

It is safer from damage and can increase the permissible load and rotation speed of the bearing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conventional underwater bearing device, and FIG. 2 is a sectional view showing an embodiment of the present invention. 1...Rotating shaft, 6...Underwater bearing, 11...Spatter. Gu - Figures

Claims (1)

[Scope of Claims] 1. Sputters are fixed to a rotating shaft adjacent to both ends of a submersible bearing provided in the body of a pump that does not have a protection pipe or bearing water supply means from the outside, and the above-mentioned A submersible bearing for a pump, characterized in that the dimensions or shapes of the two spatters are determined so as to create a difference in water pressure at both ends of the submersible bearing. 2. The underwater bearing for a pump according to claim 1, wherein the two spatters have different outer diameters. 3. A radial blade is provided on the surface of the two sputters facing the underwater bearing, and the outer diameter and inner diameter of the radial blade are
The submersible bearing for a pump according to claim 1, wherein either the number of blades or the height of the blades is different.