JP2002317793A - Movable inner ring for pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump having high durability by preventing the deterioration of a movable inner ring for holding an appropriate distance between the impeller by absorbing the deviation at the outer diameter of a mouth part of the impeller and restricting a leak of the pressure-raised liquid to a low- pressure side to improve the pumping characteristic of the pump by reducing the abrasion of the movable inner ring due to a contact with the impeller. SOLUTION: This pump is provided with the impellers fastened to the rotary shaft to be driven for rotation by a motor, and a casing for housing the impellers. The inside of a side wall of the casing is formed with a recessed part having a flat bottom surface, and the plate-like movable inner ring formed with a hole to be fitted on the outer diameter of the mouth part of the impellers with a clearance is provided in the recessed part freely to move in the radial direction to absorb the deviation at the outer diameter of the mouth part of the impeller. A side surface of the movable inner ring at a motor side thereof is provided with a ring cover for regulating the movement of the movable inner ring to the motor side through an elastic body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump having a movable inner ring provided on a side wall of a casing for suppressing a liquid pressurized by an impeller from leaking to a low pressure side.

[0002]

2. Description of the Related Art A first conventional example will be described with reference to FIG. FIG. 7 is a partial sectional view and a partially enlarged sectional view of a pump using a conventional impeller and a movable inner ring, and FIG. 7 (a) is a partial sectional view of a pump using an impeller,
FIG. 7B is a partially enlarged cross-sectional view thereof. In FIG. 7A, reference numeral 4a denotes an impeller, and the liquid flowing from a mouth portion (suction unit) of the impeller 4a is pressurized through the inside of the impeller 4a and discharged from the impeller 4a. Impeller 4a
A part of the liquid discharged from is discharged toward the movable inner ring 2a on the low pressure side, and the movable inner ring 2a prevents the liquid from leaking out of the casing 1a. The movable inner ring 2a is provided between a recess 12a provided in a side wall of the casing 1a perpendicular to the rotation axis of the impeller 4a and a ring cover 3a fixed to the casing 1a by screws 15a. That is, the casing 1a of the portion that houses the movable inner ring 2a
The thickness of the recess 12a is formed by reducing the thickness of the
The movable ring cover 2a is provided between the ring cover 3a and the movable ring cover 3a so as to be movable in the rotation axis direction of the impeller 4a.
When the movable inner ring 2a rotates the impeller 4a, the movable inner ring 2a rotates around the mouth 13a of the impeller 4a while swinging in the direction perpendicular to the rotation axis and in the axial direction.

Further, as a second embodiment, Japanese Utility Model Laid-Open No.
As disclosed in Japanese Patent No. 57400, there has been proposed a method of manufacturing an inner ring as a separate body, storing the inner ring in an outer periphery of the inner ring with an O-ring attached thereto, and press-fitting the inner ring.

[0004]

In the first conventional example, the inner ring 2a and the mouth portion 13a of the impeller 4a are provided.
By maintaining a proper gap of about 0.1 mm, the pump performance can be improved. However, when the rotation speed is 3
Although there is no problem at a low speed of 600 rpm or less, the rotation speed is 3 rpm.
When the rotation speed is 600 rpm or more, or when the water pressure is high, the influence of the contact between the mouth portion of the impeller and the inner diameter of the movable inner ring and the contact between the inner ring 2a and the casing 1a increases.

That is, since the movable inner ring 2a rotates following the rotation of the mouse 13a while sliding with the mouse 13a, the inner diameter of the movable inner ring 2a may come into contact with the mouse 13a. . For this reason,
The inner diameter of the movable inner ring 2a is worn. In particular, when the rotation speed is 3600 rpm or more, the inner diameter of the movable inner ring is greatly worn. Also, the inner ring 2a
Is driven by the rotation of the impeller 4a, and swings in the radial direction due to the eccentricity of the impeller 4a. At the same time,
The inner ring 2a is pressed against the side surface of the casing 1a by water pressure, and the end 24a of the side wall of the casing 1a is formed.
The side surface of the inner ring 2a made of a material softer than the casing 1a usually wears due to the edge.

That is, in the above conventional example, a part of the pressurized liquid, for example, water discharged from the impeller 4a flows toward the movable inner ring 2a, and is filled between the impeller 4a and the movable inner ring 2a. The movable inner ring 2a is pressed as shown by an arrow A in FIG. Since the movable inner ring 2a rotates while sliding with the mouth portion 13a of the impeller 4a, when a pressing force in the direction of arrow A is applied,
Friction occurs between the end of the casing 1a and the vicinity of the end 17a,
The vicinity of the end 17a of the movable inner ring 2a made of a material softer than the casing 1a is worn. 16
Indicates the worn portion, that is, the worn portion. For this reason,
Conventionally, in consideration of the service life of the movable inner ring, the thickness of the movable inner ring has to be designed to withstand this wear, and the thickness of the movable inner ring has to be increased.

In the second prior art, when an O-ring is attached to the outer periphery of an inner ring manufactured separately and stored in an inner ring case, the concentricity of each component is shifted and the impeller is eccentric. As a result, the inner ring and the impeller come into contact with each other, and the sliding surfaces of the inner ring and the impeller are worn, resulting in increased leakage and reduced pump performance.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, to maintain a proper gap between the mouth portion of the impeller and the inner diameter of the movable inner ring, and to solve the problem when the conditions such as high speed rotation and high water pressure are severe. Another object of the present invention is to provide a pump in which the mouth portion of the impeller and the movable inner ring are prevented from coming into contact with each other to prevent the inner diameter of the movable inner ring from being worn and the pump performance from being reduced.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a pump having an impeller fastened to a rotating shaft driven by a motor, and a casing accommodating the impeller. A plate-shaped movable inner ring in which a flat side portion is formed inside the side wall portion of the casing, and a gap is formed in the outer wall of the mouth portion of the impeller so as to be fitted with a gap therebetween in a radial direction. An elastic body is interposed between the movable inner ring and the movable inner ring, and between the movable inner ring and the movable inner ring.

As described above, according to the above configuration, even when the concentricity of each component is poor, the center of the sliding portion (mouth portion) of the impeller fastened to the rotating shaft and the center of the inner diameter of the inner ring. The concentricity can be adjusted, and the gap between the mouth part (sliding part) of the impeller and the inner diameter of the inner ring can be maintained in an appropriate state to improve the pump performance. At the same time, the impeller mouse part and the inner part can be improved. By preventing contact with the ring, wear deterioration can be prevented even at high speed rotation and high water pressure, and high pump performance can be maintained without deterioration.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the drawings by using some embodiments. FIG. 1 is a sectional view showing a first embodiment of a pump using an impeller and a movable inner ring according to the present invention. FIG. 2 is an enlarged sectional view of a main part of FIG. FIGS. 1 and 2 show an embodiment in which the movable inner ring 2a is incorporated into the side walls of resin casings 1a and 1b manufactured by resin molding.

In FIGS. 1 and 2, for example, two-stage impellers 4a and 4b are attached to a main shaft 5 connected to a rotation output shaft of a motor (not shown).
For example, two-stage resin casings 1a and 1b produced by molding are provided around a and 4b. The liquid sucked from the suction part formed by the mouth part 13a of the impeller 4a is supplied to the first-stage resin casing 1a.
The pressure is increased by the first-stage impeller 4a provided in the inside. This liquid is pressurized by a resin-made flow path member 6a forming a diffuser and a return flow path, and guided to a mouth portion 13b suction port of a second stage impeller 4b through this flow path member 6a. The pressure is increased by the impeller 4b of the stage and discharged from the discharge port 10 of the metal outer cover 7a that covers the discharge port 10 provided in the casing 1b and the two-stage casings 1a and 1b. Reference numeral 7b denotes an inner cover 7b that seals the opening of the second-stage casing 1b.

The outer cover 7a is further provided with a fluid suction port 8, and the fluid flows in from the suction port 8,
The pressure is increased by the first and second stage impellers 4 a and 4 b and the diffuser and is discharged from the discharge ports 9 and 10.

FIG. 3 is a plan view of the movable inner ring. As shown, the movable inner rings 2a, 2b
Is a resin donut-shaped disk manufactured by resin molding or compression molding, for example.
a, 4b, the outer diameter of the mouse part 13a, 13b and the outer diameter of one side
Inner diameter 21 fitted with a gap of about 0.05 to 0.2 mm
It has a sliding surface of. As shown in FIG. 2, the movable inner rings 2a and 2b
a and 1b are incorporated into the depressions 12a and 12b. The recesses 12a and 12b are formed by reducing the thickness of the side walls 11a and 11b of the casings 1a and 1b, and the circular bottom surface formed inside (the side of the impeller) is flat.

FIG. 4 is a plan view of the O-ring. The O-ring 14a is formed in a ring shape by an elastic body, and has a circular or elliptical cross section. The O-ring 14a is provided on the side wall 1 of the casing 1a, 1b.
It is supported by the projections 22a, 22b of the ring covers 3a, 3b fixed to the screws 1a, 11b by screws 15a, 15b, and is held between the casings 1a, 1b and the movable inner rings 2a, 2b.

The movable inner rings 2a, 2b inserted in the recesses 12a, 12b having flat bottoms so as to be movable in the radial direction of the impellers 4a, 4b are combined with the ring covers 3a, 3b and the movable inner rings 2a, 2b. The axial movement of the impellers 4a, 4b, that is, the inner sides thereof (i.e., the impeller side), is restricted by the O-rings 14a, 14b of the elastic body provided therebetween. In this case, O-ring 14
a and 14b are ring covers 3a and 3b for the casing 1
Due to the compressive force of the screws 15a and 15b attached to the screws a and 1b, they are deformed as shown in FIG. In the manufacture of the impellers 4a and 4b, the outer diameter of the mouth portions 13a and 13b can be formed with high accuracy to 0.05 mm or less.
The outer diameter may be eccentric with respect to the casings 1a and 1b due to misalignment. Also, the casing 1a,
1b is manufactured by resin injection molding, the side wall 11
Depressions 12a, 12b that provide flatness of the bottom surface that achieves a sealing effect of preventing the liquid from leaking due to the direct contact of the planes of the movable inner rings 2a, 2b with the respective a, 11b.
Can be easily manufactured by resin injection molding.

Therefore, the recesses 12a, 1
2b, and movable inner rings 2a, 2 nipped between ring covers 3a, 3b via O-rings 14a, 14b.
b, when assembling the pump, the mouse sections 13a, 13a
b in the radial direction following the outer diameter of the
The eccentricities of a and 13b are absorbed. When the pump is operating, the gap between the inner rings 2a, 2b and the mouth portions 13a, 13b of the impellers 4a, 4b is 0.05 to 0.2 mm.
Is kept at an appropriate value. Also, the inner rings 2a, 2b
The elastic recovery force from the O-rings 14a and 14b acts in the axial direction, and the gravitational force of the mouth portions 13a and
A constant gap is maintained without contacting the contact b. And
During the operation of the pump, the sucked liquid flows through the casings 1a and 1b.
The movable inner rings 2a and 2b are sequentially pressurized in the inside and the movable inner rings 2a and 2b are
It is possible to prevent the pressurized liquid from leaking in close contact with the bottom surfaces of 1a and 11b.

Accordingly, the movable inner rings 2a, 2b and the impellers 4a, 4b are formed by the O-rings 14a, 14b.
Of the movable inner rings 2a, 2b and the impellers 4a, 4b.
b can prevent the mouth portions 13a and 13b from coming into contact with each other, so that the wear resistance is improved even when the rotation speed is 3600 rpm or higher and the water pressure of the internal fluid is high, High pump performance can be maintained without deterioration. In addition, the movable inner rings 2a, 2
Since a gap of 0.5 mm or more is formed on one side between the outer diameter of b and the inner diameters of the depressions 12a and 12b,
The movable inner rings 2a, 2b can move radially within 0.5 mm on one side.

Next, a second embodiment of the pump according to the present invention will be described with reference to FIG. FIG. 5 is an enlarged sectional view of a main part showing a second embodiment of a pump using an impeller and a movable inner ring according to the present invention, wherein resin casings 1a and 1b are manufactured by molding movable inner rings 2a and 2b. An embodiment in the case of being incorporated in the side wall portion of the present invention will be described. In the figure, the difference from the first embodiment is
The O-ring 14a is engaged with the projection 17 formed inside the side wall 11a of the casing 1a, and the O-ring 14a
The movable inner ring 2a is arranged on the motor side surface of the motor, and a ring cover 3a is arranged on the motor side surface of the movable inner ring 2a to restrict the axial movement of the movable inner ring 2a. In this case, O-ring 14a
Is deformed by receiving a compressive force by a screw 15a attaching the ring cover 3a to the casing 1a. Then, the elastic recovery force from the O-ring 14a acts on the movable inner ring 2a in the axial direction, and a certain gap is maintained without contacting the mouth portions 13a and 13b of the impeller by its own gravity. Then, the sucked liquid is pressurized in the casing 1a, and the movable inner ring 2a is further pressed against the O-ring 14a by the pressurized liquid, so that leakage of the pressurized liquid is suppressed, and the same as in the first embodiment. The effect of is obtained. In this embodiment, even if the movable inner rings 2a, 2b are deformed toward the side walls of the casings 1a, 1b by the pressurized liquid, the protrusions 17 are formed.
Contact with the movable inner ring 2a,
No wear occurs on the surface facing the side wall of 2b.

Next, a third embodiment of the pump according to the present invention will be described with reference to FIG. FIG. 6 is an enlarged sectional view showing a main part of a third embodiment of a pump using an impeller and a movable inner ring according to the present invention. This embodiment is shown in FIG.
This is an improvement of the embodiment shown in FIG. In the embodiment shown in FIGS. 1 and 2, the pressurized liquid presses the movable inner rings 2a and 2b toward the side walls of the casings 1a and 1b. Since the movable inner ring 2a rotates while sliding with the mouth portion 13a of the impeller 4a, friction occurs between the movable inner ring 2a and the vicinity of the end 23a of the casing 1a, and the movable inner ring 2a is formed of a material softer than the casing 1a. The vicinity of the end 23a of the ring 2a is worn. On the other hand, in the embodiment of FIG.
A mouth portion 13a of the side wall portions 11a and 11b of the 12b portion,
The inner diameters of the ends 24a, 24b facing the 13b side (suction port side) are formed smaller than the inner diameters of the movable inner rings 2a, 2b, so that the inner diameters 21 of the movable inner rings 2a, 2b are the side walls 11a, 11b. Ends 24a, 24b
Never touch the edge of the Therefore, the casing 1
Since the contact surface pressure acting on the movable inner rings 2a, 2b made of a material softer than a, 1b is reduced, abrasion can be suppressed and breakage can be prevented, and the liquid sealing performance can be maintained. In particular, in this embodiment, the impeller 4
Since the flow path of the fluid drained from a and 4b is bent and reaches the movable inner rings 2a and 2b, the sealing performance can be further improved by the labyrinth effect.

Accordingly, the gap between the movable inner rings 2a, 2b and the mouth portions 13a, 13b of the impellers 4a, 4b is maintained at an appropriate amount, and the movable inner rings 2a, 2b
And a recess 12 having a flat bottom surface of the casing 1a, 1b.
Since the contact surface pressure with the a and 12b can be reduced, the abrasion resistance is improved even at a high rotation speed of 3600 rpm or more and when the water pressure of the internal fluid is high, without deteriorating the high pump performance. Can be maintained. In this embodiment, the side wall 11 provided with the depressions 12a and 12b is provided.
The ends 24a and 24b of the mouse parts 13a and 1b
3b extends to approximately the same plane as the inner diameter of the end 13a,
13b may be smaller than the inner diameter 21 of the movable inner rings 2a, 2b. For example, even in the vicinity of the outer diameter of the mouth portions 13a, 13b, wear of the movable inner rings 2a, 2b can be prevented.

As described above, according to the present invention, while maintaining a proper gap between the mouth portion of the impeller and the inner diameter of the movable inner ring, high pump performance can be obtained, and high-speed rotation and high water pressure can be achieved. Even when the conditions are severe, it is possible to prevent the mouth portion of the impeller from contacting with the movable inner ring, prevent deterioration due to wear, and suppress a decrease in pump performance.

Furthermore, according to the present invention, it is configured such that contact between the side wall of the casing and the movable inner ring can be avoided. Alternatively, even when the side wall of the casing is in contact with the movable inner ring, the inner diameter of the end of the side wall facing the mouth portion is smaller than the inner diameter of the movable inner ring. Thus, it is possible to prevent the surface of the movable inner ring facing the side wall from being worn. Therefore, the thickness of the movable inner ring can be made smaller than the thickness of the conventional movable inner ring.

Further, the eccentricity (variation in concentricity) of the mouth portion of the impeller fastened to the rotary shaft is absorbed, the gap between the impeller and the inner ring is maintained at an appropriate amount, and the pressurized liquid moves to the low pressure side. By providing a movable inner ring on the side wall of the casing for suppressing the leakage of water and improving the lift characteristics of the pump, it is possible to realize a pump having a long life of the movable inner ring by eliminating parts that deteriorate due to wear.

[0025]

As described above, according to the present invention, it is possible to prevent the mouth portion of the impeller from contacting the inner diameter of the movable inner ring, thereby preventing the inner diameter of the movable inner ring from being deteriorated by abrasion. Further, it is possible to prevent the surface of the movable inner ring facing the side wall from being worn.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a pump using an impeller and a movable inner ring according to the present invention.

Figure 2 is an enlarged sectional view of FIG.

FIG. 3 is a plan view of a movable inner ring.

FIG. 4 is a plan view of an O-ring.

FIG. 5 is an enlarged sectional view of a main part of a second embodiment of the pump using the impeller and the movable inner ring according to the present invention.

FIG. 6 is an enlarged sectional view of a main part showing a third embodiment of a pump using an impeller and a movable inner ring according to the present invention.

FIG. 7 is a partial sectional view and a partially enlarged sectional view of a conventional pump using an impeller and a movable inner ring.

[Explanation of symbols]

1a, 1b: casing, 2a, 2b: movable inner ring, 3a, 3b: ring cover, 4a, 4b: impeller, 5: main shaft (rotating shaft), 6a, 6b: flow path member, 7a
... Outer cover, 7b ... Inner cover, 8 ... Suction port, 9,1
0: discharge port, 11a, 11b: side wall, 12a, 12b
... recess, 13a, 13b ... mouse part of impeller, 14a,
14b: O-ring, 15a, 15b: Screw, 17: Projection, 21: Inner diameter of movable inner ring, 22a, 22
b: protrusion, 23a: end.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Tanaka 7-1-1, Higashi Narashino, Narashino-shi, Chiba Industrial Machinery Group, Hitachi, Ltd. (72) Inventor Sachio Fujita 7-1-1, Higashi-Narashino, Narashino-shi, Chiba No. F term in the Industrial Equipment Group, Hitachi, Ltd. (reference) 3H022 AA01 BA02 CA34 CA54 DA08 DA13 3H034 AA01 BB01 BB06 CC04 DD02 DD24 EE09 EE11 EE13 3J040 BA02 BA03 FA05 HA04

Claims (4)

[Claims] An impeller fastened to a rotating shaft driven by a motor, a casing accommodating the impeller, and a side surface formed by flattening an inside of a side wall of the casing. A plate-shaped movable inner ring having a hole to be fitted with a gap provided with respect to the outer diameter of the mouth portion of the impeller, an elastic body, and movement of the movable inner ring toward the impeller are regulated. A ring cover, wherein the movable inner ring is disposed between the side portion and the ring cover so as to be movable in a radial direction of the mouth portion, and between the side portion provided on the side wall portion and the movable inner ring. And an elastic body interposed between any one of the movable inner ring and the ring cover. 2. An impeller fastened to a rotating shaft driven to rotate by a motor, a casing accommodating the impeller, and a side surface formed by flattening the inside of a side wall of the casing. A plate-shaped movable inner ring formed with a hole to be fitted and provided with a gap with respect to the outer diameter of the mouth portion of the impeller, an O-ring made of an elastic body, and a projection supporting the O-ring. A ring cover for restricting movement of the movable inner ring toward the impeller, wherein the movable inner ring is movable between the side surface and the ring cover in a radial direction of the mouth part. The pump is arranged, and the O-ring is supported by a protrusion of the ring cover, and the O-ring is interposed between the movable inner ring and the ring cover. 3. The pump according to claim 2, wherein an inner diameter of said side surface portion facing said mouth portion is smaller than an inner diameter of said movable inner ring. 4. An impeller fastened to a rotating shaft driven to rotate by a motor, a casing accommodating the impeller, and a side surface formed by flattening the inside of a side wall of the casing. A projection provided at an end of the side surface, a plate-shaped movable inner ring having a hole formed to provide a gap with an outer diameter of a mouth portion of the impeller, and an elastic body; An o-ring, and a ring cover that regulates the movement of the movable inner ring toward the impeller, wherein the movable inner ring is formed so that the movable inner ring can be moved in the radial direction of the mouth portion. A pump disposed between the movable inner ring and the side ring, the O-ring being supported by the protrusion, and the O-ring being interposed between the side surface and the movable inner ring.