JPH0110443Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a Pelton water turbine, and particularly to a Pelton water turbine in which air inlets and outlets are provided in the casing. Conventional Pelton turbines have holes at the top of the casing that allow air to freely enter and exit in order to maintain the pressure inside the casing at approximately atmospheric pressure, and form a maze to prevent liquid from leaking outside. It is structured so that However, in such a configuration, a small amount of liquid may rotate with the runner and be blown outward by centrifugal force at the top of the casing and enter the air hole. Furthermore, if the runner is at high speed, the centrifugal force is large. , a small amount of liquid may leak to the outside through the air hole. Furthermore, in order to prevent this, it is uneconomical to complicate the structure of the air hole or to position the air hole further above.

In order to eliminate the above-mentioned drawbacks, this invention provides an air hole below the center of the runner, which also serves as a drain for the shaft seal.

To explain the figures, Fig. 1 is a side sectional view of a conventional Pelton water turbine, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and 1 is a water conduit pipe that guides high-pressure water from a high place. , 2 is a needle valve, 3 is a casing, 31 is an upper half of the casing, 32 is a lower half, 4 is a nozzle, 5 is a runner, 6 is a bucket for the runner, 7 is a packing, and 8 is a packing presser. ,
9 indicates a main shaft, and 10 indicates a bearing. Reference numeral 11 denotes an air hole provided in the upper part of the upper half 31 of the casing 3, and 12 is a cover thereof, so that the outlet of the air hole forms a labyrinth.

However, in such a configuration, as mentioned above, a small amount of liquid rotates with the runner, is blown outward by centrifugal force, and may enter the air hole.Furthermore, if the runner is at high speed, the centrifugal force is large, so
However, a small amount of liquid may leak out through the air holes, which is a drawback.

Figure 3 is a side sectional view of the Pelton turbine of this invention.
FIG. 4 is a sectional view taken along the line A--A in FIG. 3, and the same reference numerals as in FIGS. 1 and 2 represent the same parts.

In this invention, the air hole 21 is connected to the shaft sealing part 20.
It is located outside the runner in the lower half of the casing, below the center of the runner, and communicates with the inside of the casing 3. The liquid injected from the nozzle 4 hits the bucket 6 of the runner 5, imparts rotational force to the runner 5, and then falls due to gravity as shown by arrow F.
At this time, a small amount of the liquid that hits the runner rotates with the runner and is splashed into the casing by centrifugal force, but it travels along the inner wall of the casing and falls to the bottom. Since the air hole 21 is located in the lower half of the casing, is located below the center of the runner, and faces downward, there is no fear that the splashed liquid will leak from the air hole 21. In this manner, with this invention, air can freely enter and exit from the air holes 21 without fear of liquid leakage, and the inside of the casing can be maintained at approximately atmospheric pressure.

Furthermore, since the air hole 21 is provided outside the shaft seal 20, the liquid leaking from the shaft seal 20 can return to the inside of the casing 3 through the air hole 21, so there is no need to provide a separate drain hole.

The Pelton turbine of this invention has the above-mentioned configuration, and has a relatively simple structure that can maintain the pressure inside the casing at approximately atmospheric pressure, reliably prevent leakage of liquid to the outside, and prevent the shaft from leaking. This provides an extremely low-cost Pelton water wheel that has an air hole that can also serve as a drain hole in the sealing part.

[Brief explanation of drawings]

Figure 1 is a side sectional view of a conventional Pelton turbine, Figure 2
The figure is a sectional view taken along line A-A in Figure 1, Figure 3 is a side sectional view of the Pelton turbine of this invention, and Figure 4 is a sectional view of the Pelton turbine of this invention.
FIG. 3 is a cross-sectional view taken along line A-A in the figure. Explanation of symbols: 1... Water pipe, 2... Needle valve, 3... Cover, 4... Nozzle, 5... Runner, 6... Bucket, 7... Bucking, 8...
Packing foot, 9...Main shaft, 10...Bearing, 1
1... Air hole, 12... Cover, 20... Shaft seal, 21... Air hole.

Claims (1)

[Scope of utility model registration request] In Pelton water turbines where the rotating shaft of the water turbine is installed horizontally, a hole that allows air to freely enter and exit the casing is provided outside the shaft seal and at a position lower than the center of the runner of the water turbine. The characteristic Pelton water wheel.