JPS6212880Y2 - - Google Patents

Description

[Detailed description of the invention] This invention consists of a fixed ring fixed to the casing side of a mechanical seal provided on the pump shaft, and a rotating ring attached to the pump shaft that allows floating to press against the fixed ring to prevent leakage from the sliding surface of the rotating ring attached to the pump shaft. In this way, the leakage liquid leaking into the casing from the play between the fixed ring and the pump shaft is removed from the drain hole formed in the casing before reaching the bearing attached to the casing to support the pump shaft. The mechanical seal device for the pump is configured to completely drain the leaked liquid, and the first purpose is to completely drain the leaked liquid, and the length between the bearing insertion part of the pump shaft and the impeller is shortened as much as possible to prevent vibration. However, the second purpose is to prevent the bearing from being affected by leaked liquid at all.

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a vertical land pump, in which a casing 1 has a motor case part 2, a large fixed ring fitting hole 3,
A pump casing part 4 and a discharge passage 5 are provided, and a drain plate hole 6 is provided on the side of the fitting hole 3. The insertion opening of the fitting hole 3 is provided in the upper end wall of the lower pump casing part 4. Inside the pump casing part 4,
A support arm 7 of any shape, such as a ring shape, protruding from the side is provided at a position that does not interfere with the aforementioned insertion opening of the fitting hole 3, and an end plate 8 with a suction passage 9 formed therein is attached to the lower end opening. A vortex chamber 11 having a suction port 10 at the center of the side is formed, and the vortex chamber 11 is communicated with the discharge path 5.

A pump shaft 13 serving as a main shaft is passed through the center of the fitting hole 3 and a motor main portion 12 protruding into the volute chamber 11 is fitted into the motor case portion 2, and the pump shaft 13 is inserted into the support hole immediately above the fitting hole 3. 15 is supported by a bearing 14 fitted from above. After a large fixed ring 29 (to be described later) is fitted into the fitting hole 3 and fixed to the support arm 7, an impeller back plate 16 having a cylindrical part 17 in the center is attached, and a boss 19 is attached to the lower end of the pump shaft 13. The impeller 18 whose upper end fits into the cylindrical part 17
to fix.

Reference numeral 21 denotes a mechanical seal composed of a rotating ring 22 and a fixed ring 23, and the pump shaft 13
A V-shaped ring 2 on the lower surface of the rotary ring 22 is fitted with an O-ring 24 on the inner circumference so as to be able to move slightly in the axial direction.
5 and the V-shaped ring 2 on the top surface of the boss 19 of the impeller 18
6, fit the upper and lower ends of the approximately diamond-shaped elastic ring 27 into the cross section slightly compressed in the axial direction, and
7 in the height direction is compressed by a spring fastening ring 28 and fastened to the pump shaft 13 so as not to rotate. Fixed ring 23 whose lower end surface contacts the rotating ring 22
is fitted into the fitting hole 3 and onto the lower surface of the large fixed ring 29 fixed by a retaining ring 43. Large fixed ring 29
An annular hole 30 surrounding the outer periphery of the pump shaft 13 is provided inside the annular hole 30, and an outflow port 31 made by cutting out a part of the peripheral wall communicates with the drain hole 6 to connect to the first wall 32 on the lower side.
and an upper second wall 33, and a fitting hole 34 for the fixed ring 23 is provided on the lower surface of the first wall 32.
A cylindrical part 35 that protrudes into the annular hole 30 is formed on the upper side, and the fixed ring 23 and the pump shaft 13 are attached to the cylindrical part 35.
A first drain hole 36 communicating the annular hole 30 with the gap between the holes and a first tapered hole 37 on the inner periphery of the upper end are provided. The second wall 33 is located slightly below the bearing 14, and is provided with a second drain hole 38 communicating with the annular hole 30 and a second tapered hole 39. The first tapered hole 37 and the second tapered hole 39 are formed concentrically in a portion through which the pump shaft 13 passes, and the first tapered hole 37 has a slightly smaller diameter.

The pump shaft 13 has a first taper 40 and a second taper hole 3 that fit into the first taper hole 37 with a slight distance between them.
A labyrinth 41 is provided between the second-stage taper 42 and the second-stage taper 42 that fit into the annular hole 30 with a slight distance between them. position within.

In the pump of the above embodiment, as the pump shaft 13 rotates, water and other liquids blown in by the impeller 18 are compressed in the swirl chamber 11, and are discharged into the discharge passage 5 through the upper surface of the impeller back plate 16. Rotating ring 22 and fixed ring 2 of mechanical seal 21
The sliding friction of the seal ring on the corresponding surface of No. 3 seals the pump shaft 13 to prevent liquid from rising, but if a small amount of leakage liquid increases the looseness between the fixed ring 23 and the pump shaft 13. , most of it is blocked by the first stage taper 40 and leaked from the first drain hole 36 into the annular hole 30, and a small amount of leaked liquid rises in the minute space between the first stage taper 40 and the first taper hole 37. The labyrinth 41 is prevented from rising further due to the labyrinth of uneven circumferential surfaces and is shaken off into the annular hole 30 by centrifugal force.However, the extremely small amount of leaked liquid that could not be shaken off from the pump shaft 13 is leaked to the second stage taper 42 and the second stage taper 42. When a small amount of water between the taper holes 39 rises, it is shaken off by the slope of the second stage taper 42 and returned to the annular hole 30 from the second drain hole 38, and all of it is discharged to the outside from the drain hole 6. Drain the leaked liquid.

As clarified by the description of the above embodiments, in the present invention, the pump shaft 13 is passed through a large fixed ring 29 that is fitted into a casing and then supported by a bearing 14. Inside the large fixed ring 29, there are:
An annular hole 30 surrounding the pump shaft and communicating with the drain hole 6 of the casing by cutting a part of the peripheral wall.
The large fixed ring 29 is provided with a first wall 32 on the side to which the fixed ring 23 is fixed, and a second wall 33 in front of the bearing 14.
The inner diameter is reduced in the direction of the tapered hole 3 of the first wall 32.
A first stage taper 40 that fits into the taper hole 39 of the second wall 33 with a slight distance between them is provided, and a second stage taper 42 that fits into the taper hole 39 of the second wall 33 with a slight distance between the first and second stage tapers 4.
Since a labyrinth 41 is formed between 0 and 42, this structure allows even if a small amount of liquid leaks from between the fixed ring 22 fixed to the pump shaft 13 and the fixed ring 22, the first stage The taper 40, the labyrinth 41, and the second stage taper 40 shake off the water by centrifugal force before it reaches the bearing 14, enter the annular hole 30 of the large fixed ring 29, and be discharged from the drain hole 6. First stage taper and taper hole 3
In front of 7, a tapered hole 3 is used to collect a small amount of liquid that leaks from between the movable ring 22 and the fixed ring 23 and is shaken off by centrifugal force.
A first drain hole 36 that enters the annular groove 30 from the first wall 32 without passing through the pump shaft 13 is provided.
In addition to reducing the amount of leaked liquid adhering to the first stage taper 40 of the second stage taper 40 of the second stage taper 40 of the second stage taper 42 of the second stage taper 42 of the second stage taper 42 of the second wall 33, although this is almost impossible, , bearing 1
4, the second drain hole 38 of the second wall 33 is returned to the annular hole 30.
4 is prevented from being affected by leaked liquid, the mechanical seal reliably prevents even the slightest liquid leakage, and has the effect of preventing the bearing 14 from leaking.

[Brief explanation of the drawing]

The accompanying drawings show an embodiment of the present invention, with FIG. 1 being a partially cutaway front view showing the main part, and FIG. 2 being an enlarged cutaway front view of the main part. 4... Pump casing part, 6... Drain plate hole, 11... Volute chamber, 13... Pump shaft, 14...
... Bearing, 18 ... Impeller, 21 ... Mechanical seal, 22 ... Rotating ring, 23 ... Fixed ring, 27 ... Elastic ring, 29 ... Large fixed ring, 3
0... Annular hole, 31... Outlet, 32... First wall, 33... Second wall, 36... First drain hole, 3
7...First tapered hole, 38...Second drain hole, 3
9...Second tapered hole, 40...First stage taper, 4
1... Labyrinth, 42... Second stage taper.

Claims (1)

[Scope of utility model registration request] The fixed ring 23 of the mechanical seal is fixed to a large fixed ring 29 that passes through the pump shaft in the center, and a part of the peripheral wall surrounding the pump shaft is cut out to drain the casing inside the large fixed ring 29. A first wall 32 is provided with an annular hole 30 communicating with the plate hole 6 to fix the fixed ring 23 to the large fixed ring 29, and a second wall 33 on the side of the bearing 14 is provided.
A fixed ring 2 is attached to the first wall 32 and the second wall 33.
A tapered hole 37 whose inner diameter is reduced in the direction of 3,
A first step taper 40 and a second step taper 42 are fitted with a slight distance between the two tapers 39, and a labyrinth 41 is provided between the first and second step tapers to match the annular hole 30.
A fixed ring 23 is formed on the first wall 32 described above.
A pump characterized in that a first drain hole 36 is provided which communicates the play between the pump shaft 13 and the annular hole 30, and a second drain hole 38 is formed in the second wall 33 and which communicates with the annular hole 30. mechanical seal device.