JP2004132426A - Shaft sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shaft sealing device suitable for a submersible pump, in particular, having low cost and good assembling workability without manufacturing a special shaft, and holding its sealing performance without the abnormal wear of a shaft even in liquid including sand and slurry, the residence of the liquid in a circular gap on the outer periphery of a shaft guide-down portion and the face roughness and opening due to the accumulation of deposits resulting in the poor start of the pump or biting between sliding faces. <P>SOLUTION: A fixed sealing ring 6 is supported by a housing 1, the shaft guide-down portion 7 having a fitted shaft sleeve 14 is loosely fitted to the fixed sealing ring 6 and a shaft through-hole 4 to hold a circular gap 8 on the outer peripheral face of the shaft sleeve 14, a rotary sealing ring 9 is fitted to the shaft sleeve 14 so that it is rotated right over the fixed sealing ring 6 together with the shaft and has slide contact with the fixed sealing ring with spring energization, and a stirring blade 13 extending decliningly to the rotating direction of the shaft is attached to the outer peripheral face of the shaft sleeve 14. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shaft sealing device mounted on a submersible pump or the like.
[0002]
[Prior art and its problems]
As is well known, in a submersible pump, generally, a shaft through-hole is formed in the center of a partition wall interposed between a pump vortex chamber and an oil chamber, and an annular groove recessed on the outer periphery of the upper end of the through-hole is provided. A fixed sealing ring of the shaft sealing device is fitted, and an annular gap is provided on the outer periphery of the fixed sealing ring and the shaft guiding portion loosely fitted in the shaft through-hole. The rotating seal ring is fitted to the lower portion of the shaft guide so as to be in sliding contact with the fixed seal ring by force, but the liquid retained in the annular gap precipitates solids due to sliding heat and the like, and the deposits are fixed. It adheres to the inner circumference of the seal ring and the shaft through-hole and accumulates and causes a start failure of the pump. In addition, the above-mentioned deposits are caught between the sliding contact surfaces of the fixed seal ring and the rotary seal ring, and the surface is caught. Seal performance due to roughening and face opening It will be inhibited. In order to solve such a problem, there is a method in which a spiral groove is formed on the outer periphery of the shaft guiding lower portion so as to push out the precipitate to the pump chamber side by a screw pump action accompanying rotation of the shaft (for example, Patent Document 1). 1).
[0003]
[Patent Document 1]
JP 2000-274380 A (FIG. 1)
[0004]
[Problems to be solved by the invention]
However, in the structure of Patent Document 1, a general-purpose shaft cannot be used, and it is necessary to manufacture a special-purpose shaft. Therefore, the cost increases and the strength of the shaft remains problematic. In addition, there is also a difficulty in assembling such that the auxiliary member such as the O-ring is easily damaged by the spiral groove when the rotary seal ring is assembled. Further, according to the structure of Patent Document 1, it is suitable for use in a highly viscous liquid such as oil, but if it is used in a liquid containing sand, slurry, etc. as in a construction site, the shaft can be used. The engraved spiral groove causes abnormal wear and causes an early breakage accident of the shaft. In addition, the repair work associated with the wear of the spiral groove is a major repair in which the entire shaft is replaced, requiring a large repair cost.
[0005]
The present invention solves the above-mentioned problems, does not require a special-purpose shaft to be manufactured, uses a general-purpose shaft, does not reduce the strength, can be easily assembled at low cost, and uses sand, slurry, etc. There is no abnormal wear of the shaft due to the agitation, the agitation in the annular gap around the lower part of the shaft guide prevents the liquid from stagnating, and the pump does not start poorly due to the accumulation of deposits, and bites between the sliding contact surfaces. It is an object of the present invention to provide a shaft sealing device that maintains sealing performance without causing surface roughening and surface opening due to the above, and is particularly suitable for a submersible pump.
[0006]
Configuration of the Invention
In the shaft sealing device according to the present invention, a ring groove is recessed on the outer side of the upper end of the shaft through hole to form a housing for supporting a fixed sealing ring, and the fixed sealing ring of the shaft sealing device is fitted into the ring groove. The shaft guide lower part fitted with the shaft sleeve is loosely fitted in the fixed sealing ring and the shaft through-hole so as to have an annular gap on the outer periphery of the shaft sleeve. The rotary seal ring was fitted to the shaft sleeve so as to be in sliding contact with the stationary seal ring, and a stirring blade extending downward in the rotation direction of the shaft was attached to the outer peripheral surface of the shaft sleeve.
[0007]
【Example】
Hereinafter, description will be made with reference to FIGS. 1 and 2 in which the submersible pump is implemented.
[0008]
Reference numeral 1 denotes a partition wall interposed between the pump chamber 2 and the oil chamber 3, and a ring groove 5 is recessed outside the upper end of a shaft through hole 4 formed in the center to constitute a housing for a fixed seal ring support. Then, the fixed sealing ring 6 of the shaft sealing device is fitted into the ring groove 5. Reference numeral 7 denotes a shaft guide lower portion of the motor, and a shaft sleeve 14 is fitted in a portion extending from the oil chamber 3 to the pump chamber 2. The shaft sleeve 14 is loosely fitted in the fixed sealing ring 6 and the shaft through hole 4. The outer periphery of the sleeve 14 has an annular gap 8. Reference numeral 9 denotes a rotary seal ring which is loosely fitted to the outer periphery near the upper end of the shaft sleeve 14 immediately above the fixed seal ring 6 and is mounted so as to rotate with the shaft via a bellows 10 and a retainer 11. It is in sliding contact with the stationary sealing ring 6 by the bias. A stirring blade 13 is provided on the outer peripheral surface of the shaft sleeve 14 so as to extend downward in the rotation direction of the shaft.
[0009]
[Action]
When the shaft rotates and the submersible pump is driven, the liquid in the annular gap 8 is stirred by the stirring blade 13 and pushed out toward the pump chamber 2, and does not stay in the annular gap 8, so that precipitation in the liquid is prevented. In addition to preventing the matter from adhering and accumulating on the inner peripheral surface of the stationary sealing ring 6 and the shaft through-hole 4, the solid substance itself is prevented by the cooling action. In addition, accompanying members such as the bellows 10 are not damaged when the rotary seal ring 9 is assembled.
[0010]
【The invention's effect】
According to the present invention, the assembly work can be easily performed at low cost without reducing the strength by using a general-purpose shaft without manufacturing a dedicated shaft, and the annular gap on the outer periphery of the shaft guide portion 7 The liquid in the agitator 8 is agitated to prevent stagnation and to provide a cooling action, so that the pump does not start poorly due to deposition of deposits. The sealing performance is maintained without causing surface roughening or opening due to biting, there is no abnormal wear of the shaft against liquids including sand or slurry, and if the stirring blade 13 is worn, only the shaft sleeve 14 is worn. Has to be replaced, and the entire shaft does not need to be replaced, and there is an advantage that a shaft sealing device suitable particularly for a submersible pump can be obtained.
[Brief description of the drawings]
FIG. 1 is a vertical sectional side view of a main part of a shaft sealing device of the present invention mounted on a submersible pump.
FIG. 2 is a bottom view of a shaft sleeve in the device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing for fixed sealing ring support 4 Shaft through-hole 5 Ring groove 6 Fixed sealing ring 7 Shaft lower part 8 Annular gap 13 Stirring blade 14 Shaft sleeve

Claims (1)

A shaft in which a ring groove is recessed outside the upper end of the shaft through hole to form a housing for supporting a fixed sealing ring, a fixed sealing ring of a shaft sealing device is fitted into the ring groove, and a shaft sleeve is fitted therein. The guide portion is loosely fitted in the fixed sealing ring and the shaft through-hole to have an annular gap around the outer periphery of the shaft sleeve, and rotates together with the shaft immediately above the fixed sealing ring to rotate so as to slidably contact the fixed sealing ring by spring bias. A shaft sealing device, wherein a sealing ring is fitted to a shaft sleeve, and a stirring blade extending downward in a direction of rotation of the shaft is attached to an outer peripheral surface of the shaft sleeve.

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