JP2004360576A - Non-leakage pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a non-leakage pump capable of transferring even a fluid to be flowed with non-leakage and high slurry density. <P>SOLUTION: There is provided a magnetic non-leakage pump 1 whose rotating shaft 18 rotates by magnetic force. In the magnetic non-leakage pump 1, a portion between the anterior chamber 16f of a casing for housing the anterior part of the rotating shaft 18 and the posterior chamber 16b of the casing for housing the posterior part of the rotating shaft 18 is sealed by a mechanical seal 28. The inside of the posterior chamber 16b is filled with a lubricant fluid to lubricate the bearings 26a, 26b of the rotating shaft 18 inside the posterior chamber16b, and a thrust bush 50 by the lubricant fluid. A blade 48 formed in a holding portion 38 is rotated to give a centrifugal force to the lubricant fluid, while the centrifugal force circulates the lubricant fluid between the posterior chamber 16b and a lubricant fluid tank 58, and filters the lubricant fluid by a filter 62 inside the lubricant fluid tank 58. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a leak-free pump used for transporting a fluid containing a particulate component.
[0002]
[Prior art]
Conventionally, a gland packing or a mechanical seal has been used for a shaft sealing structure of a pump in order to prevent leakage of a fluid to be transmitted. However, it is difficult to completely prevent liquid leakage of the fluid to be transmitted by these shaft sealing structures. Therefore, the use of a non-leakage pump having a non-seal structure completely prevents leakage of the fluid to be transmitted. As a non-sealable non-leakage pump, there is a magnet type pump that rotates a rotating shaft magnetically and lubricates a bearing with a fluid to be transmitted (for example, see Patent Document 1). In this leak-free pump, a lubrication groove is formed in the bearing of the rotating shaft, and the fluid to be transmitted flowing through the lubrication groove lubricates the bearing.
[0003]
[Patent Document 1]
JP-A-11-324969
[Problems to be solved by the invention]
However, the non-sealable non-leakage pump in which the bearing is lubricated with the fluid to be transmitted has the following problems.
When the fluid to be transmitted contains particles, the particles may block the lubrication grooves. For this reason, the transmitted fluid that can be transported by the non-seal structure non-leakage pump is limited to those having a slurry concentration of 3% or less. For transporting the fluid to be fed having a slurry concentration of more than 3%, a pump using a gland packing or a mechanical seal as a shaft sealing structure is used, and liquid leakage of the fluid to be sent cannot be completely prevented.
The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a non-leakage pump capable of transporting a fluid having a high slurry concentration without causing liquid leakage. It is.
[0005]
[Means for Solving the Problems]
The present invention has the following configuration to solve the problem. A non-leakage pump according to the first aspect of the present invention includes a rotating shaft in a casing, an impeller mounted on a front portion of the rotating shaft, a bearing and an inner magnet mounted on a rear portion of the rotating shaft, and opposed to the inner magnet. A non-leakage pump in which the rotating shaft is magnetically rotated by the rotation of the disposed outer magnet, wherein a space between the front chamber of the casing that houses the front part of the rotating shaft and the rear chamber of the casing that houses the rear part of the rotating shaft is The casing is sealed by a mechanical seal, and the rear chamber of the casing is filled with a lubricating liquid for lubricating the bearings.
[0006]
According to the first aspect of the invention, the mechanical seal prevents the fluid to be transmitted from the front chamber of the casing from leaking to the rear chamber of the casing. Therefore, the lubricating fluid in the rear chamber of the casing is prevented from being contaminated by the fluid to be transmitted, and the bearing of the rotating shaft is lubricated with the clean lubricating fluid.
According to a second aspect of the present invention, there is provided the non-leakage pump according to the first aspect, wherein the holding portion of the inner magnet that rotates with the rotating shaft in the rear chamber of the casing forcibly lubricates the lubricating liquid in the rear chamber of the casing. A pressure generating mechanism for circulating the pressure is provided.
[0007]
According to the invention of claim 2, the lubricating liquid pressurized by the rotation of the holding portion of the inner magnet circulates in the rear chamber of the casing and flows continuously to the bearing of the rotating shaft.
A non-leakage pump according to a third aspect of the present invention is the non-leakage pump according to the second aspect, wherein the lubricating liquid tank, a pipeline for supplying the lubricating liquid from the lubricating liquid tank to a rear chamber of the casing, It is provided with a pipeline for returning the lubricating liquid from the rear chamber to the lubricating liquid tank, and a filtration unit for filtering the lubricating liquid supplied to the rear chamber of the casing.
[0008]
According to the third aspect of the present invention, the pressurized lubricating liquid flows out of the rear chamber of the casing to the lubricating liquid tank, and the lubricating liquid corresponding to the amount of the flow returns from the lubricating liquid tank to the rear chamber of the casing. Since the filtration unit filters the lubricating liquid, the lubricating liquid returning from the lubricating liquid tank to the rear chamber of the casing is a clean lubricating liquid. Therefore, even if the fluid to be conveyed leaks from the mechanical seal to the rear chamber of the casing and contaminates the lubricating liquid, the contaminated lubricating liquid is filtered by the filtration unit to become a clean lubricating liquid.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a configuration diagram of a non-leakage pump according to the present embodiment, and FIG. 2 is an end view of a rear end side of a holding portion in which a part is cut away.
The magnet type non-leakage pump 1 shown in FIG. 1 includes a casing configured by stacking a front cover 10c, a front casing 10f, and a back casing 10b. The front casing 10f and the back casing 10b are fixed to a frame adapter (not shown), and a front chamber 16f of the casing is formed between the front cover 10c and the front casing 10f. The back casing 10b has a bottomed cylindrical shape including a cylindrical partition wall 12 and a bottom plate 14, and a rear chamber 16b of the casing is formed between the back casing 10b and the front casing 10f.
[0010]
The rotating shaft 18 is accommodated in the casing. The rotating shaft 18 penetrates a rotating shaft hole 20 of the front casing 10f, and an impeller 22 is mounted on a tip portion of the rotating shaft 18 in the front chamber 16f. In the rear chamber 16b, sleeves 24a and 24b are mounted on the intermediate portion and the rear end portion of the rotating shaft 18, respectively. The sleeve 24a is supported by the bearing 26a, and the sleeve 24b is supported by the bearing 26b. The bearing 26a is mounted on the edge of the inner peripheral surface of the rotary shaft hole 20 on the rear chamber 16b side, and the bearing 26b is mounted on the bottom plate 14.
[0011]
At the end of the rotary shaft hole 20 on the front chamber 16f side, a mechanical seal 28 seals between the front chamber 16f and the rear chamber 16b. The fixed ring 30 of the mechanical seal 28 is mounted on the edge of the inner peripheral surface of the rotary shaft hole 20 on the front chamber 16 f side, and the rotary ring 32 of the mechanical seal 28 is mounted on the rotary shaft 18. The fixed ring 30 is located on the front chamber 16f side.
[0012]
In the rotary shaft hole 20, two annular small chambers 34a and 34b are formed between the rotary shaft 18 and the inner peripheral surface of the rotary shaft hole 20 so as to be arranged side by side from the fixed ring 30 side to the bearing 26a side. The small rooms 34a and 34b form a part of the rear room 16b, and the small room 34a and the small room 34b are separated by a wall 36. The rotating ring 32 is provided in the small room 34a. The side opposite to the wall 36 of the small room 34b is closed by the sleeve 24a and the bearing 26a.
[0013]
In the rear chamber 16b, a holding portion 38 is mounted between the sleeve 24a and the sleeve 24b of the rotating shaft 18. The holding part 38 has a double cylindrical structure including an outer cylinder 40 and an inner cylinder 42. The outer cylinder 40 and the inner cylinder 42 are connected by a plurality of legs 44 to form a gap, and the gap forms a holding section passage 46. The inlet 46i of the holding portion passage 46 is open on the front end surface 42f side of the inner cylinder 42, and the outlet 46o of the holding portion passage 46 is open on the rear end surface 42b side of the inner cylinder 42.
[0014]
The inner cylinder 42 is fixed to the rotating shaft 18 by a key (not shown). A thrust bush 50 is mounted on the rear end surface 42b of the inner cylinder 42 so as to be adjacent to the bearing 26b.
An inner magnet 64 is embedded in the outer cylinder 40. On the rear end face 40b of the outer cylinder 40, a plurality of blades 48 that are continuous from the inner peripheral edge to the outer peripheral edge of the rear end face 40b are formed as a pressure generating mechanism. A gap 52a is provided between the front end face 40f of the outer cylinder 40 and the rear face of the front casing 10f, a gap 52b is provided between the outer peripheral face of the outer cylinder 40 and the inner peripheral face of the cylindrical partition wall 12, and a rear end face 40b of the outer cylinder 40 is provided. A gap 52c is formed between the gap and the bottom plate 14, and the gap 52a, the gap 52b, and the gap 52c are continuous with each other.
[0015]
A labyrinth is formed between the edge of the inner peripheral surface on the front end surface 40f side of the outer cylinder 40 and the back surface of the front casing 10f, and the labyrinth seals between the gap 52a and the inlet 46i of the holding portion passage 46. are doing.
A continuous groove from the small chamber 34b to the entrance 46i of the holding portion passage 46 is formed in the inner peripheral portion of the bearing 26a and the side wall portion of the sleeve 24a, and this groove forms a communication passage 54a.
[0016]
A bottom plate passage 56 is formed in the bottom plate 14. One end of the bottom plate passage 56 opens on the inner surface of the bottom plate 14 facing the outlet 46o of the holding portion passage 46, and the other end opens in the gap 52d between the rear end surface 18b of the rotating shaft 18 and the inner surface of the bottom plate 14. are doing. On the inner peripheral portion of the bearing 26b and on the side wall portion of the thrust bush 50 fixed to the rear end surface 42b of the inner cylinder 42, a groove 57 is formed which is continuous from the gap 52d to the outlet 46o of the holding portion passage 46. 57 and the bottom plate passage 56 are connected via a gap 52d to form a communication passage 54b.
[0017]
A communication path 54c is formed in the front casing 10f, and one end of the communication path 54c opens to the gap 52a, and the other end opens to the small room 34a.
A lubricating liquid tank 58 is formed outside the casing, and a filter 62 as a filtering unit is provided in the lubricating liquid tank 58. The lubricating liquid tank 58 is connected to the small room 34b via the supply pipe 60s, and is connected to the small room 34a via the return pipe 60r. The interior of the rear chamber 16b is completely filled with the lubricating liquid supplied from the lubricating liquid tank 58.
[0018]
An outer magnet 66 is arranged outside the cylindrical partition 12 in correspondence with the inner magnet 64, and the outer magnet 66 is rotatably supported by a rotation drive shaft 68 provided on a frame adapter.
Next, the operation will be described.
When the outer magnet 66 is rotated, the inner magnet 64 is magnetically synchronously rotated with the holding portion 38, and the rotating shaft 18 is also rotated. The impeller 22 rotates together with the rotating shaft 18, and the fluid to be transmitted is discharged from the front chamber 16f.
[0019]
As shown in FIG. 1, when the holding portion 38 rotates, the blade 48 of the outer cylinder 40 rotates, and the lubricating liquid in the gap 52c is centrifugally acted to have a high pressure and flows through the gap 52b to the gap 52a.
The high-pressure lubricating liquid flowing into the gap 52a flows to the small room 34a through the communication passage 54c, and further flows to the lubricating liquid tank 58 through the return pipe 60r. A rotating ring 32 of the mechanical seal 28 is provided in the small room 34a, and a high-pressure lubricating liquid flows to a sliding contact portion between the rotating ring 32 and the fixed ring 30, and the sliding contact portion is always lubricated with the lubricating liquid.
[0020]
The lubricating liquid continuously flows from the holding portion passage 46 to the gap 52c after the lubricating liquid flows out to the gap 52a. The low-pressure lubricating liquid flows from the lubricating liquid tank 58 to the holding portion passage 46 through the supply pipe 60s, the small room 34b, and the communication passage 54a. The lubricating liquid flowing through the communication passage 54a lubricates the bearing 26a.
Part of the lubricating liquid that has exited the outlet 46o of the holding portion passage 46 flows through the communication passage 54b from the bottom plate passage 56 to the groove 57. The lubricating liquid flowing in the groove 57 lubricates the bearing 26b and the thrust bush 50.
[0021]
Although the mechanical seal 28 seals between the front chamber 16f and the rear chamber 16b, it is difficult to completely prevent the fluid to be transmitted from the front chamber 16f from leaking into the rear chamber 16b. The transmitted fluid leaked from the front chamber 16f into the rear chamber 16b enters the small room 34a and contaminates the lubricating liquid in the small room 34a. The contaminated lubricating liquid flows through the return pipe 60r to the lubricating liquid tank 58, is filtered by the filter 62, and the cleaned lubricating liquid is circulated and supplied to the rear chamber 16b.
[0022]
Therefore, the particles in the fluid to be transmitted do not hinder the lubrication of the bearings 26a, 26b and the thrust bush 50, and even the fluid to be transmitted having a slurry concentration of more than 3% is transported by the non-leakage pump 1 without causing liquid leakage. it can.
Further, the bearing 26a, the bearing 26b, and the thrust bush 50, which are lubricated by the lubricating liquid, can be formed of a metal, a resin, or the like.
[0023]
Further, since the mechanical seal 28 seals between the front chamber 16f and the rear chamber 16b, the bearings 26a and 26b can be arranged near the front chamber 16f, and the rotating shaft 18 can be stably supported. Rotation becomes possible.
In this embodiment, it is also possible to form the legs 44 in the form of axial flow blades and pressurize the lubricating liquid with the legs 44.
[0024]
【The invention's effect】
ADVANTAGE OF THE INVENTION The leak-free pump of this invention has the effect that the transmitted fluid with a high slurry concentration can be transported, without causing a liquid leak.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a non-leakage pump showing one embodiment of the present invention.
FIG. 2 is an end view of a rear end side of a holding part with a part cut away.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Leakless pump 10c Front cover 10f Front casing 10b Back casing 12 Cylindrical partition wall 14 Bottom plate 16f Casing front chamber 16b Casing rear chamber 18 Rotation shaft 18b Rotation shaft rear end face 20 Rotation shaft hole 22 Impellers 24a, 24b Sleeves 26a, 26b Bearing 28 Mechanical seal 30 Fixed ring 32 Rotating ring 34a, 34b Small chamber 36 Wall 38 Holding section 40 Outer cylinder 42 Inner cylinder 44 Leg 46 Holding section passage 48 Blade 50 Thrust bush 52a, 52b, 52c, 52d Gap 54a, 54b, 54c Communication path 56 Bottom plate path 57 Groove 58 Lubricating liquid tank 60r Return pipe 60s Supply pipe 62 Filter 64 Inner magnet 66 Outer magnet 68 Rotation drive shaft

Claims (3)

A rotating shaft is provided in the casing, an impeller is mounted on the front of the rotating shaft, a bearing and an inner magnet are mounted on the rear of the rotating shaft, and the rotating shaft is magnetically driven by the rotation of an outer magnet placed opposite the inner magnet. A rotating leak-free pump,
The front chamber of the casing accommodating the front part of the rotating shaft and the rear chamber of the casing accommodating the rear part of the rotating shaft are sealed by a mechanical seal,
A leak-free pump characterized in that a rear chamber of a casing is filled with a lubricating liquid for lubricating a bearing. The leak-free pump according to claim 1, wherein the holding portion of the inner magnet that rotates together with the rotating shaft in the rear chamber of the casing has a pressure generating mechanism for forcibly circulating the lubricating liquid in the rear chamber of the casing. A lubricating liquid tank, a pipe for supplying the lubricating liquid from the lubricating liquid tank to the rear chamber of the casing, a pipe for returning the lubricating liquid from the rear chamber of the casing to the lubricating liquid tank, and a lubricating liquid supplied to the rear chamber of the casing 3. The non-leakage pump according to claim 2, further comprising: a filtration unit that filters the water.

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