JPH0426698Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application This invention relates to an improvement of the bearing structure of the split guide vane portion of a once-through water turbine.

B. Summary of the design This design aims at a bearing structure for the split guide vane of a once-through water turbine that can reduce the water resistance caused by the partition plate in a once-through water turbine that uses split guide vanes, as well as reduce the surface pressure on the guide vane mounting shaft. The bearing structure of the guide vane part is formed by attaching a support pin protruding toward the divided guide vane side to a partition plate to form a guide vane mounting shaft part,
A guide vane attachment shaft insertion hole is formed in the partition plate side wall surface of the guide vane body, and the split guide vane is supported by inserting the guide vane attachment shaft portion into the guide vane attachment shaft insertion hole.

When the bearing structure of the divided guide vane portion is configured in this manner, the thickness of the partition plate can be reduced, and the surface pressure of the guide vane mounting shaft can be reduced.

C. Prior Art As shown in FIG. 4, in a once-through water turbine, a runner 1 is rotatably supported by a casing 4 via its rotating shaft 3, and a casing 4 is provided on the upstream side of the runner 1.
An inlet pipe 5 is connected to the runner 1, and on the outlet side of the inlet pipe 5 there is a guide vane 6 having an airfoil-shaped cross section that adjusts the amount of water flowing into the runner 1. Both ends of the guide vane 6 are supported by the casing 4 via bearings. It is attached so that it can be opened and closed freely. Further, a water discharge pipe 7 is provided on the downstream side of the runner 1 and connected to the casing 4, and the water flowing in from the inlet pipe 5 is adjusted in water amount by a guide vane 6 and enters the runner 1. The structure is such that water is discharged from the outer periphery and drained to the outside through a water discharge pipe 7.

A once-through water turbine with this structure cannot be operated efficiently when the amount of water is small, so in order to efficiently operate the once-through water turbine by supplying water only to a portion of the runner 1, a split guide vane in which the guide vane 6 is divided into two in the axial direction is used. There is a once-through water wheel of the type used.

As shown in FIG. 5, the bearing structure of the split guide vane portion of this type of once-through water turbine is such that two guide vanes 6a and 6b are connected to each other via bearings 10 at one end of the partition plate 9 that partitions the casing 4. are attached so that they can rotate independently, and the other end is attached to the casing 4 so that they can rotate via a bearing 8, and these guide vanes 6a, 6b are connected to a handle attached to the outside of the casing 4. 11 for opening and closing operations.

However, the divided guide vanes 6a, 6 of the above structure
Since the side ends of the partition plate 9 in b are supported separately by bearings 10 attached to the partition plate 9, the thickness B of the partition plate 9 has to be considerably thick, and water This not only creates resistance to the flow, but also causes the flow direction of the water to be oblique, resulting in an inconvenience that reduces the operating efficiency of the once-through water turbine.

The applicant of this invention has resolved this inconvenience,
In order to provide a divided guide vane for a once-through turbine that reduces resistance to water and does not disturb the water flow direction, Utility Model Application No. 56-48485 proposes a guide vane that is divided into two parts in the axial direction.
The thickness B of the partition plate 9 is reduced by rotatably supporting the outer ends of the guide vanes connected in a straight line on the casing, and by rotatably fitting the partition plate side connecting parts of each guide vane into each other. I showed what I tried to do. For example, as shown in FIG. 6, in the guide vane connection part A of the partition plate 9, the shaft 6e of one guide vane 6a is formed to have a larger diameter than the end part 6c on the casing 4 side, and is oriented in the axial direction of the center part. A hollow hole is formed, and a bearing 10 is placed on the inner periphery of the hollow hole.
The outer periphery of the shaft 6e is supported by a bearing 10 attached to the partition plate 9 so that it can rotate freely. The shaft 6f of the other guide vane 6b is rotatably supported by a bearing 10 installed in the hollow hole, so its outer diameter is smaller than that of the end 6d on the casing 4 side. axis 6e of 6a
The two guide vanes 6a and 6b are fitted in a hollow hole bearing 10 and arranged in a straight line in a connected state.

With such a structure, the thickness B of the partition plate 9 can be made thinner than in the case where the center sides of each guide vane 6a, 6b are independently supported on the partition plate 9.

Furthermore, as shown in FIGS. 7 and 8, the ends 6c and 6d of the respective shafts of the guide vanes 6a and 6b on the casing 4 side are rotatably supported via bearings 8 attached to the casing 4, respectively. In the connecting part A at the center, a hollow hole with a depth extending from the center side to the end on the casing 4 side is formed in one guide vane 6a, and bearings 10 are fitted into both ends of this hollow hole, respectively. be. The shaft 6f of the other guide vane 6b is supported by a bearing 10 in a hollow hole of the guide vane 6a, so that it can rotate freely.
It is formed long enough to exceed. Therefore, the guide vane 6a has a complete double shaft structure, and there is no need to provide a bearing in the partition plate 9. Therefore, the thickness B of the partition plate 9 can be made extremely thin since it only has the function of partitioning the casing 4.

D Problems to be solved by the invention However, if the bearing part of the guide vane of a once-through water turbine is made to have the bearing structure proposed in Utility Model Application No. 56-48485,
Although the thickness of the partition plate could be made thinner, it had the disadvantage of increasing the bearing surface pressure. This idea was made in order to eliminate the drawbacks of the split guide vanes in once-through water turbines mentioned above.In order to reduce the resistance of the partition plates to the flow of water, the thickness of the partition plates is made thinner, and the guide vanes are The present invention aims to provide a bearing section for a divided guide vane of a once-through water turbine that reduces surface pressure on the bearing section.

E Means and operation for solving the problem The bearing structure of the divided guide vane portion of the once-through water turbine of this invention to achieve the above object is such that a support pin protruding toward the divided guide vane side is attached to the partition plate to guide the divided guide vane. While forming a vane mounting shaft, a guide vane mounting shaft insertion hole is formed on the side wall surface of the partition plate of the guide vane body, and the guide vane mounting shaft is inserted into the guide vane mounting shaft insertion hole. It is characterized by supporting the.

Since the guide vane mounting shaft that supports the split guide vane is made up of support pins attached to the partition plate, it can sufficiently support the split guide vane even if the partition plate is made thinner, reducing water resistance. can be made smaller.

Furthermore, the bearing on the outer periphery of the guide vane mounting shaft can reduce the surface pressure that the bearing of the guide vane receives.

Furthermore, the structure allows the guide vane mounting shaft to be freely attached to the guide vane body, and the partition plate is removably attached to the guide vane mounting shaft, making it easy to assemble and disassemble the split guide vane. can be done.

F. Embodiment An embodiment of this invention will be described below based on the drawings.

FIG. 1 and FIG. 2 respectively show a partial cross-sectional perspective view of a bearing structure of a divided guide vane portion of a once-through water turbine according to an embodiment, and a cross-section of an essential part thereof taken along line X-X. The illustrated bearing structure of the divided guide vane section includes a support pin 20 attached to the center of the partition plate 9 so as to protrude toward the divided guide vanes 6a and 6b, and a bearing 10 on the outer periphery of the support pin 20. Installed guide vane mounting shaft and guide vanes 6a, 6b
It has a guide vane attachment shaft insertion hole 21 formed on the side wall surface of the partition plate of the main body.

In addition to the above-mentioned mounting shaft, the divided guide vanes 6a and 6b are rotatably connected to a bearing 8 attached to the casing 4 so as to rotatably support the guide vane shaft 6c.

Providing a center hole 22 at the tip of the guide vane attachment shaft insertion hole 21 in the wall surface of the split guide vanes 6a and 6b described above is convenient for processing the guide vanes.

The support pin 20 can be attached to the partition plate 9 by making a hole in the partition plate 9 and then shrink-fitting the pin 20.
As shown in FIG. 9, from one side of the partition plate 9, push the small diameter end of the support pin 20 into the hole 9a of the support plate, make the tip protrude toward the other divided guide vane side, and then insert the small diameter part. An outer cylinder 20a having the same diameter as the pin part 20
After mounting, the plate 20b is further fitted to the tip of the narrow diameter part, and the plate 20 is attached via the screws 20c, 20c.
b and the outer cylinder 20a may be fixed to the pin 20.

Also, as shown in Figure 3b, a pin 20 is attached to the tip.
After inserting a rod having a diameter 20a different from the diameter 20a into the hole of the partition plate 9, leave a bevel on the entire circumference or part of the hole provided in the partition plate 9, and weld it as shown in B to partition the pin 20. Fix it to the plate 9. In this case, the pin will have guide vane attachment shaft portions with different diameters on both guide vane sides.

In addition, the plate thickness B of 9 should be the minimum plate thickness that can support the load applied to this fulcrum pin. Therefore, as shown in Figures 4 and 5, the thickness of B is Although it is necessary to increase the thickness of the plate to some extent, this proposal allows for a very thin plate. In addition, in the structure shown in Fig. 6, the shaft of 6f is thin and long, and the load applied to it is the sum of the loads of both guide vanes 6a and 6b, so a thick shaft is required, and the size of the guide vane also increases. Due to the large size, the range that can be manufactured is limited, but since the proposed structure has no restrictions on the length of the shaft and bearings, it can be applied to once-through turbines of all sizes and has practical effects. It's big.

G. Effects of the invention As is clear from the above explanation, the bearing structure of the divided guide vane portion of the once-through water turbine according to this invention allows the partition plate to be made thinner, thereby making it possible to downsize the entire water turbine.

If the partition plate is thick, the resistance of the water (which becomes an obstacle in the flow) will increase and the efficiency will decrease.
This method provides a highly efficient water turbine with minimal resistance.

Material cost savings.

In conventional manufacturing methods, this part was extremely difficult to process because it was located inside the box-shaped structure, but with this method, the process is extremely simple as the pin is inserted into a simple hole. can be converted into

[Brief explanation of the drawing]

Figures 1 and 2 are partially sectional perspective views of the bearing structure of the divided guide vane portion of the once-through water turbine of the embodiment, and sectional views of main parts thereof taken along line X-X. Figure 4 is a partial cross-sectional perspective view showing the structure of a conventional once-through water turbine. Figure 5 is a bearing structure of the divided guide vane of a conventional once-through water turbine. 6 is a sectional view of the main part showing the bearing structure of the split guide vane part of another conventional once-through water turbine.
7 and 8 are a sectional view of a main part showing a bearing structure of a divided guide vane part of another conventional once-through water turbine, and a sectional view of the main part along Y-Y. In the drawing, 4 is a casing, 6a, 6b are guide vanes, 6c, 6d, 6e, 6f are guide vane shafts, 8, 10 are bearings, 9 is a partition plate, 20, 20
a is a support pin, and 21 is a guide vane attachment shaft insertion hole.

Claims (1)

[Scope of utility model registration request] A guide vane mounting shaft is formed by attaching a support pin protruding toward the divided guide vane side to the partition plate, and a guide vane mounting shaft insertion hole is formed on the partition plate side wall surface of the guide vane body to form a guide vane mounting shaft. A bearing structure for a divided guide vane portion of a once-through water turbine, characterized in that the divided guide vane is supported by inserting the divided guide vane portion into a guide vane mounting shaft insertion hole.