JP2578510B2 - Pump device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pump device for pumping a fluid by an impeller, and more particularly to a structure for preventing contamination of a fluid in a pump system.

(Prior Art) In a pump device such as a regenerative pump or a centrifugal pump (centrifugal pump), an impeller is disposed in a fluid passage provided in a casing, and the impeller is rotated from the outside of the fluid passage via a rotating shaft. The rotation of the impeller sucks fluid from the suction port of the fluid passage, and discharges the fluid from the discharge port of the fluid passage. A mechanical seal is provided to prevent the fluid from leaking to the outside.

Since this mechanical seal has a sliding portion on the rotating side and a fixed side, abrasion powder is generated by abrasion of this portion, and the abrasion powder generates impurities as a fluid on the fluid passage side, that is, in the pump system. Contaminates fluids by contaminating them.

Even if such contamination is slight, it is unsuitable as a pump device used in ultrapure water, food, biotechnology, medicine, the chemical industry, and the like.

For this reason, it has been considered to provide a discharge passage for discharging the fluid near the mechanical seal from the fluid passage side of the mechanical seal to the outside of the casing.

(Problems to be Solved by the Invention) As described above, in the pump device, when the discharge passage for discharging the fluid near the mechanical seal to the outside of the casing from the fluid passage side of the mechanical seal is provided, the sliding contact portion of the mechanical seal is provided. The generated abrasion powder can be excluded from the pump system, but merely providing the discharge passage causes another problem.

That is, if the discharge passage is open when the pump is stopped, air may enter the pump system as the pressure of the fluid in the pump system decreases, and impurities may enter the pump system together with the air. Then new pollution occurs,
In some cases, exposure to air in the fluid in the pumping system can cause bacteria to form and cause significant contamination. Further, if the liquid stops, and there is a contamination source at the discharge destination, there is a possibility that the inside of the pump may be contaminated by the diffusion action.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and when a pump is operated, abrasion powder generated from a sliding contact portion of a mechanical seal is discharged to the outside of a casing through a discharge passage, so that a fluid caused by the mechanical seal is discharged. It is an object of the present invention to provide a pump device capable of preventing contamination of the pump system and preventing entry of air and impurities into the pump system via a discharge passage when the pump is stopped.

(Means for Solving the Problems) A pump device according to claim 1, wherein a casing having a fluid passage, an impeller rotatably disposed in the fluid passage of the casing, and a connected rotary of the impeller. A pump having a shaft, a mechanical seal for sealing a fluid transmitted from the fluid passage to the outer periphery of the rotary shaft, and a discharge passage for discharging fluid near the mechanical seal from the fluid passage side of the mechanical seal to the outside of the casing. In the device,
An electromagnetic valve which is opened and closed by an electric signal interlocked with the operation of the pump is provided in the discharge passage.

A pump device according to claim 2, wherein the casing has a fluid passage, an impeller rotatably disposed in the fluid passage of the casing, a rotating shaft connected to the impeller, and a rotating shaft from the fluid passage. A mechanical seal that seals the fluid transmitted to the outer periphery of the pump, and a discharge passage that discharges a fluid near the mechanical seal from the fluid passage side of the mechanical seal to the outside of the casing.
A relief valve is provided in the discharge passage, the relief valve being opened and closed by a change in fluid pressure on the fluid passage side in conjunction with the operation of the pump.

A pump device according to a third aspect of the present invention is the pump device according to the first or second aspect, wherein a space for receiving fluid discharged from the vicinity of the mechanical seal is formed in the middle of the discharge passage, and a solenoid valve or relief is provided outside the space. A valve is provided.

(Operation) In the pump device according to the first aspect, the electromagnetic valve is opened by an electric signal interlocked with the operation of the pump, and wear powder generated from the sliding contact portion of the mechanical seal is discharged to the outside of the casing through the discharge passage. In addition, the electromagnetic valve is closed by an electric signal that is interlocked with the stop of the pump, and prevents air and impurities from flowing back into the pump system through the discharge passage.

In the pump device according to the second aspect, the relief valve is opened by a change in the fluid pressure on the fluid passage side interlocked with the operation of the pump, and wear powder generated from the sliding contact portion of the mechanical seal is discharged to the outside of the casing through the discharge passage. The relief valve closes due to a change in the fluid pressure on the fluid passage side that is discharged and interlocks with the stop of the pump, preventing air and impurities from flowing back into the pump system through the discharge passage.

According to the pump device of the third aspect, in addition to the operation of the pump device of the first or second aspect, since the fluid is discharged through the space of the discharge passage, even if the opening / closing operation of the solenoid valve or the relief valve is slightly delayed. The adverse effects of this do not occur immediately.

(Example) An example of a pump device of the present invention will be described with reference to the drawings.

First, FIG. 1 shows a regeneration pump according to the first embodiment.

In FIG. 1, reference numeral 1 denotes a hollow casing. A cover 3 is attached to one end (the right end in the drawing) of the casing 1 via an O-ring 2 in a liquid-tight manner to form a space 4 inside the casing 1. Are formed, and mechanical seals 5 and 6 are provided on one side and the other side in the space 4, respectively. One side of the mechanical seals 5 and 6 is rotatably supported by a bearing (not shown). Large diameter portion 7a of the rotating shaft 7
The cover 9 is rotatably and liquid-tightly penetrated, and the cover 9 is attached to the other end (left end in the drawing) of the casing 1 via an O-ring 8 in a liquid-tight manner. 1, a small-diameter male screw portion 7b on the tip side of the rotary shaft 7 protrudes from the space 10.

Here, the mechanical seal 5 on one side is provided with an annular fixed seal body 16 on the cover 3 via an O-ring 15 and a fixed ring 17 on the cover 3 with a screw (not shown).
By fixing the O-ring 15
Through the O-ring 18 around the large-diameter portion 7a of the rotating shaft 7 at the other side of the fixed seal body 16. The seal body 19 is provided in a liquid-tight manner, and the rotary ring 20 is fixed to the other side of the rotary seal body 19 around the large diameter portion 7a of the rotary shaft 7 with screws 21.
A coil spring 22 is provided between the rotary ring 20 and the rotary seal body 19.
Is interposed.

The mechanical seal 5 is for sealing a fluid transmitted to the outer periphery of the rotating shaft 7, and includes a rotating seal body 19.
When the rotary shaft 7 is rotated by a motor (not shown), the rotary seal 19 rotates together with the rotary ring 20 and the rotary shaft 7 and is fixed to the rotary seal 19 when the rotary shaft 7 is rotated by a motor (not shown). The seal body 16 is slidably contacted in a liquid-tight manner so as to stop the liquid leakage. The liquid leakage in other parts than the sliding contact portion is stopped by the O-rings 15 and 18.

Further, the mechanical seal 6 on the other side is provided by disposing an annular fixed seal body 26 on the casing 1 via an O-ring 25 and fixing the fixed ring 27 to the casing 1 with a screw (not shown). The fixed seal body 26 is pressed against the casing 1 in a liquid-tight manner via the O-ring 25, and is positioned on one side of the fixed seal body 26 around the large diameter portion 7a of the rotary shaft 7. A ring-shaped rotary seal 29 is provided in a liquid-tight manner via an O-ring 28, and a coil spring 30 is interposed between the rotary ring 20 and the rotary seal 29.

This mechanical seal is used for an impeller 35 described later.
To seal the fluid transmitted from the fluid passage 37 side to the outer periphery of the rotary shaft 7 so as not to enter the space 4 side.
Similarly to the mechanical seal 5, the rotary seal body 29 is in close contact with the fixed seal body 26 by the coil spring 30, and when the rotary shaft 7 is rotated by a motor (not shown), the rotary seal body 29 is The rotary seal body 29 and the stationary seal body 26 are slidably contacted in a liquid-tight manner so as to stop liquid leakage. To stop at.

Further, an impeller 35 is provided in the space 10 on the other side of the casing 1.
The impeller 35 is a male screw of the rotary shaft 7.
It is fixed to a nut 7b with a nut 36, and is fastened to a step 7c of the rotating shaft 7.

A large number of blade grooves 35b are formed on both sides of the outer periphery of the disk portion 35a of the impeller 35, and are formed on the outer peripheral surface and side surfaces of the disk portion 35a, and groove-shaped fluid passages 37 corresponding to the blade grooves 35b are formed.
Are formed on the inner periphery of the casing 1 in the shape of a circular arc with ends.
One end of the fluid passage 37 is formed with a suction port for liquid such as ultrapure water (not shown), and the other end of the fluid passage 37 is formed with a discharge port for liquid (not shown).

Then, in this regeneration pump, the fluid passage
When the rotating shaft 7 is driven by a motor and the impeller 35 is rotated in a state where the liquid is passed through 37, the liquid in the many blade grooves 35b of the impeller 35 receives velocity energy and pressure energy by centrifugal force, and The liquid in the groove 35b passes through the fluid passage from outside the blade groove 35b.
37, and the liquid in the fluid passage 37 flows into the blade groove 35b.
Flows into the blade groove 35b from the side of the blade, and a vortex of the liquid is generated.

Then, in the fluid passage 37, the velocity energy is converted into pressure energy, and by repeating such an operation in a large number of blade grooves 35b of the impeller 35, the pressure of the liquid in the fluid passage 37 is gradually increased. The liquid is sucked from the suction port, the pressure is increased in the fluid passage 37, and then the liquid is discharged from the discharge port.

At this time, in the mechanical seal 6 for the fluid passage 37, the rotary seal body 29 and the fixed seal body 26
Are in sliding contact with each other, and this part wears and generates abrasion powder,
This abrasion powder may be mixed as impurities into the fluid on the fluid passage 37 side, that is, the fluid in the pump system, and contaminate the fluid discharged from the discharge port.

Therefore, in this pump device, the mechanical seal 6
A discharge passage 41 for discharging the fluid near the mechanical seal 6 from the fluid passage 37 side to the outside of the casing 1 is provided, and the fluid mixed with the abrasion powder as an impurity is removed from the fluid passage 37 side.

That is, in this embodiment, a shaft hole is formed at the center of the rotating shaft 7.
42, through holes 43, 44 are formed in the shaft hole 42 from both sides of the O-ring 28 on the outer surface of the rotary shaft 7, and further, a through hole 45 is formed in the upper part of the casing 1. As a result, the rotating shaft 7 is moved from the fluid passage 37 side of the mechanical seal 6.
Through the through hole 43, the shaft hole 42, and the through hole 44, through the space 4, through the through hole 45 in the casing 1, and to the outside.
And an on-off valve 46 in the through hole 45 of the discharge passage 41.
Is arranged.

Here, the on-off valve 46 for opening and closing the discharge passage 41 is, in conjunction with the operation of the pump, automatically opened at the time of operation and automatically closed at the time of stoppage, for example, switching which is switched according to the operation of the pump. A switch, a pressure switch for detecting a fluid pressure due to the operation of the pump, a solenoid valve which is opened and closed by an electric signal from a flow switch for detecting a fluid flow rate due to the operation of the pump, or a pressure increase of the liquid in the space 4 due to the operation of the pump. Use a relief valve that opens.

Therefore, during operation of the pump, the pressure of the fluid in the fluid passage 37 increases, so that the fluid mixed with the abrasion powder in the vicinity of the mechanical seal 6 on the fluid passage 37 side as impurities passes through the through hole 43 and the shaft hole 42 of the discharge passage 41. The fluid is discharged into the space 4 through the through hole 44, and when the pump is operated, the on-off valve 46 is automatically opened, so that the fluid discharged into the space 4 flows through the through hole 45 of the discharge passage 41. Then, it is discharged outside the casing 1.

Thus, when the pump stops, the pressure of the fluid in the fluid passage 37 decreases.
Automatically closes, the discharge passage 41 including the space 4 is closed, and air or fluid flows from the space 4 through the through hole 44, the shaft hole 42, and the through hole 43 of the discharge passage 41 to the fluid passage 37 side, That is, it does not enter the pump system.

In addition, 47 is a closing body, and this closing body 47
In order to form the shaft hole 42, a through hole 48 formed at the tip of the rotating shaft 7 is closed.

FIG. 2 shows a regeneration pump according to a second embodiment.

In FIG. 2, reference numeral 51 denotes a discharge passage.
As in the case of the discharge passage 41 of the first embodiment, the mechanical seal 6 is moved from the fluid passage 37 side of the mechanical seal 6.
The fluid in the vicinity is discharged to the outside of the casing 1.

The discharge passage 51 is formed by forming a through hole 52 in the rotary seal body 29 of the mechanical seal 6 and further forming a through hole 45 in the upper part of the casing 1 as in the first embodiment. A discharge passage 51 extending from the fluid passage 37 side to the outside through the through hole 52 of the rotary seal body 29, through the space 4, through the through hole 45 of the casing 1, is formed.

In the second embodiment, since the configuration and operation of other parts than the discharge passage 51 are the same as those of the first embodiment,
The same portions are denoted by the same reference numerals and description thereof will be omitted.

Therefore, also in the case of the regenerative pump of the second embodiment, when the pump is operated, the pressure of the fluid in the fluid passage 37 increases, so that the fluid in which the abrasion powder near the mechanical seal 6 on the fluid passage 37 side is mixed as an impurity. Is discharged into the space 4 through the through hole 52 of the discharge passage 51, and when the pump is operated, the on-off valve 46 is automatically opened. It is discharged to the outside of the casing 1 through the through hole 45.

Thus, when the pump stops, the pressure of the fluid in the fluid passage 37 decreases.
Automatically closes, so that the discharge passage 51 including the space 4 is closed, and air or fluid enters the fluid passage 37 side from the space 4 through the through hole 51 of the discharge passage 51, that is, into the pump system. There is no.

FIG. 3 shows a regeneration pump according to a third embodiment.

In FIG. 3, reference numeral 61 denotes a mechanical seal. The mechanical seal 61 is, like the mechanical seal 6 of the first and second embodiments described above, a large-diameter portion of the rotary shaft 7.
7a is rotatably and liquid-tightly penetrated so that the fluid transmitted from the fluid passage 37 side where the impeller 35 is located to the outer periphery of the rotary shaft 7 is sealed so as not to enter the space 4.

The mechanical seal 61 is provided on the casing 1
A holding ring 65 holding an annular fixed seal body 64 is provided via rings 62 and 63, and the fixed ring 66 is attached to the casing 1 with screws 67.
To fix the fixed ring 66 to the holding ring 65 and the casing 1 in a liquid-tight manner via the O-ring 68, and the holding ring 65 to the casing via the O-rings 62 and 63. 1 in a liquid-tight manner, and
64, a holding ring 71 holding an annular rotating seal body 70 is provided in a liquid-tight manner around the large-diameter portion 7a of the rotating shaft 7 via an O-ring 69. A rotating ring 72 is fixed around the large diameter portion 7a of the rotating shaft 7 with a screw 73 at one side of the ring 71, and a coil spring 74 is interposed between the rotating ring 72 and the holding ring 71. Structure.

Also, similarly to the mechanical seal 6 of the first and second embodiments described above, the mechanical seal 61 has the rotary seal body 70 in close contact with the fixed seal body 64 by the coil spring 74, and is driven by a motor (not shown). When the rotary shaft 7 rotates, the rotary seal 70 is held by the holding ring 71 and the rotary ring.
The rotary seal member 70 and the stationary seal member 64 are slidably contacted with each other in a liquid-tight manner to stop liquid leakage.
It stops at 2,63,65,69.

Reference numeral 81 denotes a discharge passage. The discharge passage 81 is formed from the fluid passage 37 side of the mechanical seal 61 in the same manner as the discharge passage 41 of the first embodiment and the discharge passage 51 of the embodiment of FIG. A fluid near the casing 4 is discharged to the outside of the casing 4. A through-hole 82 is formed in an upper portion of a holding ring 65 that holds the fixed seal body 64 of the mechanical seal 61. By forming a through-hole 83 in the upper part of the casing 1, a discharge passage 81 from the fluid passage 37 side of the mechanical seal 61 to the outside through the through-hole 82 of the holding ring 65 and the through-hole 83 of the casing 1 is formed. is there.

In the third embodiment, the configuration and operation of other parts than the mechanical seal 61 and the discharge passage 81 are the same as those of the first and second embodiments. The same reference numerals are given and the description is omitted.

Therefore, also in the case of the regenerative pump of the third embodiment, when the pump is operated, the pressure of the fluid in the fluid passage 37 increases, and the on-off valve 46 is automatically opened. The fluid mixed with the abrasion powder as an impurity is discharged to the outside of the casing 1 through the through holes 82 and 83 of the discharge passage 81.

Thus, when the pump stops, the pressure of the fluid in the fluid passage 37 decreases.
Automatically closes, so that the discharge passage 81 is closed, and air or fluid flows through the discharge passage 71 to the fluid passage 37 side,
That is, it does not enter the pump system.

FIG. 4 shows a regeneration pump according to a fourth embodiment.

In FIG. 4, reference numeral 91 denotes a discharge passage.
Similarly to the discharge passage 41 of the first embodiment, the discharge passage 51 of the embodiment of FIG. 2 and the discharge passage 81 of the third embodiment, the mechanical seal 61 is moved from the fluid passage 37 side of the mechanical seal 61. A fluid near to the outside of the casing 1 is discharged to the outside of the casing 1.
By forming a through hole 92 with respect to the distal end of the casing 1, a discharge passage 91 extending from the fluid passage 37 side of the mechanical seal 61 to the outside through the through hole 92 of the casing 1 is formed.

In the fourth embodiment, the configuration and operation of other parts than the discharge passage 91 are the same as those of the third embodiment.
The same parts are denoted by the same reference numerals and description thereof is omitted.

Therefore, also in the case of the regenerative pump of the fourth embodiment, during operation of the pump, the pressure of the fluid in the fluid passage 37 increases, and the on-off valve 46 is automatically opened. The fluid mixed with the abrasion powder is discharged to the outside of the casing 1 through the through hole 92 of the discharge passage 91.

Thus, when the pump stops, the pressure of the fluid in the fluid passage 37 decreases.
Automatically closes, so that the discharge passage 91 is closed, and air or fluid flows through the discharge passage 91 to the fluid passage 37 side,
That is, it does not enter the pump system.

In each of the embodiments described above, the discharge passages 41, 51, 81, 91
The on-off valve 46 that opens and closes automatically opens in operation and automatically closes when stopped in conjunction with the operation of the pump. It is possible to eliminate the adverse effects caused by the delay.

In the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. 2 among the above-described embodiments, since the space 4 is provided in the middle of the discharge passages 41 and 51, the fluid of the mechanical seal 6 is The fluid discharged from the passage 37 side is temporarily stored in the space 4 and then discharged to the outside. Therefore, even if the opening / closing operation of the on-off valve 46 is slightly delayed, the adverse effect immediately occurs. Never.

In each of the above-described embodiments, in addition to the on-off valve 46,
When the throttle valve is disposed in the discharge passage, the discharge amount of the fluid during operation of the pump can be adjusted. In particular, among the above-described embodiments, the first embodiment of FIG. 1 and the first embodiment of FIG. In the second embodiment, when a valve that is manually opened and closed is used as the on-off valve 46, the amount of fluid discharged during operation of the pump can be adjusted by the on-off valve 46.

(Effect of the Invention) According to the pump device of the first aspect, the electromagnetic valve is opened by an electric signal interlocked with the operation of the pump, and wear powder generated from the sliding contact portion of the mechanical seal is discharged through the discharge passage together with the fluid in the vicinity thereof. Through the pump system to the outside to prevent wear powder from being mixed as impurities into the fluid discharged from the pump.Also, the solenoid valve is closed by an electric signal that interlocks with the stoppage of the pump, and the exhaust valve passes through the discharge passage. As a result, air and impurities can be prevented from flowing back into the pump system, and the fluid in the pump system can be prevented from being contaminated and bacterial growth can be prevented.

According to the pump device of the second aspect, the relief valve opens due to a change in the fluid pressure on the fluid passage side in conjunction with the operation of the pump, and the abrasion powder generated from the sliding contact portion of the mechanical seal is discharged together with the fluid near the discharge passage. Through the pump system to the outside to prevent wear powder from being mixed as impurities into the fluid discharged from the pump. Also, a relief valve is provided by a change in fluid pressure on the fluid passage side in conjunction with the stoppage of the pump. Is closed, and air or impurities can be prevented from flowing back into the pump system through the discharge passage, so that the fluid in the pump system is not contaminated and bacterial growth can be prevented.

According to the pump device of the third aspect, in addition to the effect of the pump device of the first or second aspect, since the fluid is discharged through the space of the discharge passage, the opening / closing operation of the solenoid valve or the relief valve is somewhat delayed. However, it is possible to prevent the adverse effects from occurring immediately.

[Brief description of the drawings]

1 to 4 are cross-sectional views of a regenerative pump showing first to fourth embodiments of the pump device of the present invention, respectively. DESCRIPTION OF SYMBOLS 1 ... Casing, 4 ... Space, 6 ... Mechanical seal, 7 ... Rotating shaft, 35 ... Impeller, 37 ... Fluid passage, 4
1, 51, 81, 91 ... discharge passage, 46 ... on-off valve.

Claims (3)

(57) [Claims] 1. A casing having a fluid passage, an impeller rotatably disposed in the fluid passage of the casing, a rotating shaft connected to the impeller, and transmission from the fluid passage to the outer periphery of the rotating shaft. A mechanical seal for sealing the fluid,
A pump device comprising: a discharge passage for discharging a fluid near the mechanical seal from the fluid passage side of the mechanical seal to the outside of the casing; an electromagnetic valve that opens and closes the discharge passage with an electric signal interlocking with operation of a pump. A pump device comprising: 2. A casing having a fluid passage, an impeller rotatably disposed in the fluid passage of the casing, a rotating shaft connected to the impeller, and transmission from the fluid passage to the outer periphery of the rotating shaft. A mechanical seal for sealing the fluid,
A pump device comprising a discharge passage for discharging a fluid near the mechanical seal from the fluid passage side of the mechanical seal to the outside of the casing, wherein a change in fluid pressure on the fluid passage side interlocked with the operation of the pump is provided in the discharge passage. A relief valve that opens and closes according to the following. 3. A space for receiving fluid discharged from the vicinity of the mechanical seal is formed in the middle of the discharge passage, and an electromagnetic valve or a relief valve is disposed outside the space. A pump device as described.