WO1999030040A1

WO1999030040A1 - Pumping device formed by sheet-metal working

Info

Publication number: WO1999030040A1
Application number: PCT/JP1997/004484
Authority: WO
Inventors: Yukimasa Nakatsukasa
Original assignee: Ebara Corporation
Priority date: 1997-12-08
Filing date: 1997-12-08
Publication date: 1999-06-17
Also published as: AU5138298A

Abstract

A pumping device formed by sheet-metal working which is prevented from being deformed due to pressure change and has a good efficiency. According to the invention, a pumping device comprises a motor section (M) and a pump section (P) which are integrally formed, an impeller (7) provided in a pump casing (4) and rotated by a motor (2), a mechanical seal (11) supported by a cover casing (5) to seal a rotating shaft (3) of the impeller, and a support member (21, 12A) secured on a side of the motor (2) to support a radially inner side of the cover casing (5) so as to prevent the cover casing (5) from being moved toward the motor by pressure changes. Thus the cover casing is supported from the side of the motor by the support member, and so malfunction of the mechanical seal is eliminated.

Description

Description Sheet metal processed pump device

BACKGROUND OF THE INVENTION The present invention relates to a sheet-metal-worked pump device comprising an integral motor portion and a pump portion and having an impeller rotated by a motor in a pump casing.

As is well known, it is known that, with the development of sheet metal processing technology, the pump device is made of sheet metal to reduce the weight. However, since pressure is applied to the pump, deformation of the sheet metal, such as stainless steel, is slow, which causes problems such as leakage of liquid and reduction in efficiency.

Accordingly, it is a primary object of the present invention to provide a pump apparatus which is made of a sheet metal and is not easily deformed by pressure fluctuation.

Another object of the present invention is to prevent the deformation of the cover casing and prevent the mechanical seal that seals the rotating shaft from being unable to seal.

Another object of the present invention is to prevent deformation of the venturi tube communicating with the suction port, to prevent the 0-ring provided at that portion from falling off, and to prevent liquid leakage.

Yet another object of the present invention is to provide a liner that works effectively in the event of pressure fluctuations, thereby reducing the amount of leakage between the impeller and the casing and preventing seizure of the liner ring. is there.

Still another object of the present invention is to provide a sheet metal processed pump device capable of easily forming an air vent hole for discharging air near the center of the impeller.

It is another object of the present invention to provide a sheet-metal-pumped pump apparatus in which a passage casing of a multi-stage pump is not damaged.

Still another object of the present invention is to provide a multi-stage pump capable of shortening the axial length of a multi-stage pump. The present invention provides a pump device that has been improved. Disclosure of the invention

ADVANTAGE OF THE INVENTION According to this invention, it comprises the motor part and the pump part integrally comprised, The impeller which rotates by a motor in pump casing is provided, and the rotating shaft is sealed by the mechanical seal supported by the cover casing. In the above-described sheet metal processed pump device, the inside of the cover casing in the radial direction is supported by a support member fixed to the motor side, thereby preventing axial deformation to the motor side.

Further, according to the present invention, an impeller, which is constituted by a motor portion and a pump portion integrally formed, is provided in a pump casing and is rotated by a motor, and a suction port provided in the suction casing is connected to the impeller via a venturi tube. In a sheet metal machined pump device communicating with the inlet, the suction casing has a guide portion extending inward at the suction port, the guide portion engaging the inside of the bench lily tube, and the bench lily. A 0-ring is housed in a step formed at the tip of the tube, and a stopper is provided outside the 0-ring.

Further, according to the present invention, a motor part and a pump part which are integrally formed are provided, an impeller rotated by a motor is provided in the pump casing, and a liner is provided between the impeller and the casing part. In the sheet metal machined pump device, the liner was provided with a U-shaped cross-section liner with the high-pressure side open, and the flange portion radially outward of the liner was attached to a step formed in the casing part. Attached to the liner holder, the inner radial flange is provided with a lip, and the outer radial flange and the inner radial flange are connected by an appropriate number of ribs. I have.

Furthermore, according to the present invention, a pump unit includes an integral motor portion and a pump portion, the pump casing includes an impeller that is rotated by the motor, and the rotating shaft is supported by the cover casing. In a sheet metal processed pump device sealed with a cull seal, an impeller is provided with an air vent hole, and the impeller is mounted on a boss mounted on a rotating shaft, and the air vent is a radius of the boss. It is partially covered by a flange that extends outward in the direction. Further, according to the present invention, a plurality of impellers, each of which includes a motor portion and a pump portion, which are integrally formed, is provided in a pump casing and is rotated by a motor, and a guide vane and a passage are provided between the impellers. In a sheet metal working pump device partitioned by a cover, a rectifying blade provided between the guide vane and the passage cover is fixed to the guide vane.

According to the present invention, a sheet metal processed pump comprising a motor portion and a pump portion integrally formed, a plurality of impellers rotated by a motor in a pump casing, and a suction port and a discharge port are provided. In the apparatus, a volute is formed radially outward of the last stage impeller, and the discharge port communicates through the volute. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a side sectional view of a pump device embodying the present invention, FIG. 2 is a diagram illustrating an effect of the pump device shown in FIG. 1, and FIG. 3 shows another modification of FIG. FIG. 4 is a side sectional view showing another modified example of FIG. 1, FIG. 5 is a side sectional view showing another modified example of FIG. 1, and FIG. , FIG. 7 is an enlarged view of a Z part of FIG. 1, FIG. 8 is an enlarged view of FIG. 7, viewed from the right side, and FIG. 9 is a view of a U of FIG. FIG. 10 is an enlarged view of a portion, FIG. 10 is a view of FIG. 9 viewed from the direction of arrow V, and FIG. 11 is a side sectional view showing one embodiment of a pump device using a number of impellers.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 shows a pump device embodying the present invention. In the figure, a pump device generally indicated by reference numeral A is composed of a pump portion P and a motor portion M, and the motor portion M is housed in a motor casing 1. The motor 2 is provided, and the rotating shaft 3 is rotated. The pump part P includes a pump casing 4 and a cover casing 5 provided on the motor portion M side of the pump casing 4, and is fixed in the pump casing 4 by the rotating shaft 3 and fixing means 10. The rotating impeller 7 is housed. But The liquid sucked from the suction port 8 provided in the pump casing 4 is pressurized by the impeller 7 and discharged from the discharge port 9 provided in the pump casing 4.

The rotating shaft 3 that drives the impeller 7 is supported by a bearing 10 on the motor side at a location penetrating through the cover casing 5, and the pump side is sealed with a mechanical seal. The central portion of the cover casing 5 is supported from the motor side by a support member, in the illustrated example, a thrust flange 12. This thrust flange 12 is made of sheet metal and formed in a frusto-conical shape.

FIG. 2 is a diagram showing the effect of the present invention. As can be seen from FIG. 1, pressure is applied to the impeller 7 side of the cover casing 5, that is, the left side of the drawing. Therefore, the cover casing 5 moves to the motor side, that is, the right side in the drawing. Then, as shown in FIG. 2, the mechanical seal 11 cannot slide between the first component 11a and the second component 11b, and leakage occurs as shown by the symbol X. However, in the present invention, since the support member 12 is provided, such a disadvantage does not occur.

FIG. 3 shows another embodiment of the present invention, which is an example in which a keyed boss 10 a is used as a fixing means of the impeller 7. The other points are substantially the same as those in FIG.

FIG. 4 shows another embodiment of the present invention. In this example, the supporting member 12A is configured by a protruding portion extending to the pump side of the front casing 15 of the module M. The other points are substantially the same as the embodiment of FIG. Each embodiment is effective for the cover casing 5 made of sheet metal.

FIG. 5 shows an example in which the support member 12A of FIG. 4 is used in the embodiment of FIG. Other points are substantially the same as those of the above-described embodiments.

FIG. 6 shows an enlarged view of the circle Y portion in FIG. As described above, the suction port 8 is attached to the pump casing 4 by, for example, welding 20.The pump casing 4 has a guide portion 6a which is bent inward at the suction port 8 and extends. 2 1 is engaged. The chamber H 1 outside the bench lily tube 21, that is, the pump casing 4 communicates with the discharge port 9 and has a high pressure. On the other hand, the chamber H 2 inside the bench lily tube 21 1 Is sucked by the impeller 7, so that the pressure is low. A 0-ring 22 is provided to prevent leakage between chambers H1 and H2. However, according to the prior art, only the 0-ring 22 is provided, and the pressure of the chamber Η1 may deform the guide portion 6a inward in the radial direction and the 0-ring may fall off. Was.

Therefore, in the present invention, a ring-shaped stopper 24 is fixed to the outside of the stepped portion 23 formed at the tip of the venturi tube 21, and the inner end 6 b of the guide portion 6 a is positioned inside the venturi tube 21. Along a predetermined length of one.

Therefore, not only the 0-ring 22 can come off, but also sufficient sealing performance can be obtained at this portion. When assembling, it is sufficient to insert the 0-ring 22 before fixing the stopper 24. The stopper 24 has an effect of receiving the high pressure of the chamber H2 and preventing the high pressure from being applied to the inner end 6b of the guide portion 6a. Therefore, it is effective for sheet metal casings. It should be noted that embodiments other than FIG. 1 can be similarly implemented.

FIG. 7 is an enlarged view of a portion surrounded by a circle Z in FIG. As is well known, a liner is provided between the impeller 7 and the casing portion 25 to seal between the rotating portion of the impeller 7 and the casing portion 25 as a fixing member. However, according to the conventional technology, the casing portion 25 has a solid type ring-shaped liner ring fixed thereto. Therefore, if the gap between the liner ring and the impeller 7 is large, the leakage is large and the pump efficiency is reduced, and if the gap is small, penetration occurs.

Therefore, in the present invention, as shown in FIG. 7, a step portion 25a is formed in the casing portion 25 extending toward the boss portion of the impeller 7, and the step portion 25a has an L-shaped cross section. A liner holder 26 is provided, and a rubber liner ring indicated generally by reference numeral 27 is attached to the liner holder 26. The liner 27 has a U-shaped cross section, and its high-pressure side is open. Accordingly, the liner ring 27 is formed of the flange portion 27a attached to the liner ring holder 26, the web portion 27b extending radially inward from the flange portion 27a, and the web portion 27b. The flange portion 27c has a lip portion 27d extending substantially perpendicularly from the radial inner edge.

Therefore, an opening 28 is formed by the flange portions 27a and 27c and the web portion 27b, and when high-pressure water flows into the opening 28, the opening 28 expands, The lip portion 27 d comes into engagement with the impeller 7. However, since excessive deformation does not favor wear and the like, an appropriate number of ribs 29 are provided at angular intervals in the circumferential direction as shown in FIG. 8 to regulate the amount of deformation.

As described above, according to the present invention, by providing the linering 27 having a U-shaped cross section, leakage can be reduced and galling can be prevented. Therefore, it is very suitable for a deformable part such as a sheet metal casing or an impeller. Incidentally, an example has been described in FIGS. 1, 3, 4, clearly der that the present invention can be applied to the example of FIG. 5 ₀

FIG. 9 is an enlarged view of a portion surrounded by a circle U in FIG. 3, and FIG. 10 is a view seen in the direction of arrow V in FIG. As is well known in FIG. 9, an air layer Ai is likely to be formed in the chamber H3 between the impeller 7 and the cover casing 5 due to a difference in centrifugal force. It is known that an air vent hole 30 is provided at an appropriate position of the impeller 7 in order to remove the air layer Ai. The reason is that the mechanical seal 11 becomes dry touch due to the air layer Ai, and there is a risk of seizure.

However, the diameter of the air vent hole 30 is preferably about 2 mm, because if the air vent hole 30 is too large, the efficiency will decrease due to leakage. On the other hand, in the impeller 7 made of sheet metal, it is easy to form a hole having a diameter of about 3.5 mm or more. However, that would make the hole too large and reduce efficiency. Therefore, in the present invention, the air vent hole 30 is configured to cover about half of the air vent hole 30 as shown in FIG. 10 by using the flange portion 10b that extends radially outward of the boss portion 10a of the impeller. is there. By doing so, the processing of the hole 30 is facilitated, and the air can be effectively exhausted.

The present invention can be applied not only to a single-stage pump but also to a multi-stage pump as in the above embodiment. An example is shown in FIG. In FIG. 11, components corresponding to FIGS. 1, 3, 4, and 5 are denoted by the same reference numerals. In the illustrated embodiment, a first-stage impeller 7a and a second-stage impeller 7b are mounted on the rotating shaft 3, and a guide is provided to partition between the impellers 7a and 7b. Daven 31 and passage cover 33 are provided. A rectifying blade 32 is provided between the guide vane 31 and the passage cover 33, and the blade 32 is fixed to the guide vane 31 by welding. Therefore, the blade 3 2 becomes free with respect to the passage cover 3 3. I have. The passage cover 33 has a pressure difference in the axial direction of the pump P. Therefore, the passage cover 33 is easily deformed during operation. On the other hand, the guide vane 31 does not deform because there is almost no pressure difference in the axial direction.

If the blade 32 is fixed to the passage cover 33, the deformation may cause stress concentration at the fixed welded portion, which may cause damage.In the present invention, the blade is fixed to the guide vane 31. No stress concentration occurs. Therefore, it is suitable for sheet metal O

Further, according to the present invention, a volute chamber 35 is formed radially outward of the final stage, that is, the second stage impeller 7 b, and communicates with the discharge port 9. That is, no guide vane is provided for the impeller 7b in the final part (the second stage in the example of FIG. 3).

When the liquid is guided from the last stage impeller through the guide vane as in the prior art, it is deviated in the axial direction from the last stage impeller 7 b at the position of the discharge port 9, and the length in the axial direction is reduced accordingly. To increase. However, in the present invention, since the discharge port 9 is provided through the polytube 35, the discharge port 9 can be located radially outward of the impeller 7b, and the length in the axial direction can be shortened.

Although all of the above embodiments have been illustrated with respect to a centrifugal pump, it is apparent that the present invention can be applied to other pump devices. The invention's effect

As described above, according to the present invention, since the cover casing supporting the mechanical seal provided on the rotating shaft is supported by the support member from the motor side, the mechanical seal does not fail.

In addition, the O-ring, which seals the fluid path from the suction port to the venturi tube, is supported by stoppers to receive high-pressure liquid, so the sealing effect is reduced and the 0-ring may fall off due to deformation. Absent.

In addition, the liner between the impeller and the casing has a U-shaped cross section with the high-pressure side open, so that leakage is small and galling can be prevented. Then, holes for letting out the air accumulated in the motor side chamber of the impeller Since part of the hole is covered, large holes can be drilled, improving workability.

In a multi-stage pump, the flow regulating blades are fixed to guide vanes that are not affected by changes in pressure, and are free from the passage cover. Therefore, stress concentration does not occur even if the passage cover is deformed.

Further, since the discharge port is communicated through the radially outer volute of the last stage impeller, the length in the axial direction can be shortened. Therefore, the present invention can be suitably implemented in a sheet metal pump device that is lightweight but relatively easily deformed.

Claims

The scope of the claims

1. A pump device made of sheet metal with a motor part and a pump part that are integrally configured, an impeller that is rotated by a motor in a pump casing, and a rotating shaft that is sealed with a mechanical seal supported by a cover casing. 3. The pump apparatus according to claim 1, wherein the cover casing has a radially inner side supported by a supporting member fixed to the motor side to prevent deformation in the axial direction toward the motor side.

2 .- The motor consists of a body and a pump. The pump casing has an impeller that rotates by the motor. The suction port provided in the suction casing is connected to the inlet of the impeller via a venturi tube. In a communicating sheet metal stamping device, the suction casing has a guide portion extending inward at the suction port, the guide portion engaging the inside of the venturi tube and the bench lily tube. A pump device made of sheet metal, characterized in that a 0-ring is accommodated in a step formed at the tip, and a stop is provided outside the 0-ring.

3. A sheet metal comprising a motor part and a pump part which are integrally formed, an impeller rotated by a motor in the pump casing, and a liner provided between the impeller and the casing part. In the machined pump device, the liner has a U-shaped cross-section liner with an open high-pressure side, and the radially outward flange portion of the liner is a liner attached to a step formed in the casing. Attached to the holder, its inner radial flange is provided with a lip, and the outer radial flange and the inner radial flange are connected by an appropriate number of ribs. A pump device processed by sheet metal.

4. A sheet metal processing machine consisting of a motor part and a pump part that are integrally formed, an impeller that is rotated by the motor inside the pump casing, and a rotating shaft that is sealed with a mechanical seal supported by a cover casing. In the pump device, the impeller has an air vent hole, and the impeller is mounted on the boss mounted on the rotating shaft. The pump device according to claim 1, wherein the air vent hole is partially covered with a flange extending radially outward of the boss portion.

5. It consists of a motor part and a pump part that are integrally formed, and has a plurality of impellers that are rotated by a motor in a pump casing, and the space between these impellers is divided by a guide vane and a passage cover. The rectifying blade provided between the guide vane and the passage cover is fixed to the guide vane.

6 .—In a sheet metal-worked pump device comprising a motor portion and a pump portion formed on the body, a plurality of impellers rotated by a motor in a pump casing, and a suction port and a discharge port are provided. A pump device formed by sheet metal processing, wherein a volute is formed radially outward of the last stage impeller, and a discharge port communicates through the volute.