JPH0355822Y2 - - Google Patents

Description

[Detailed description of the invention] (A) Industrial application field The present invention relates to an improvement of an air introduction device for a cross-flow water turbine.

(B) Conventional technology A cross-flow turbine is generally configured as shown in Figure 2. That is, FIG. 2 is a schematic configuration diagram of a general cross-flow water turbine, in which the water flowing into the water turbine runner 4 from the inlet pipe 1 through the guide ben 3 rotates the water turbine runner 4, and the water that exits the water turbine runner 4 rotates. The water is discharged through the draft pipe 5 to the water discharge yard 6, and the water level 7 is discharged from the lower part of the water turbine runner 4.
Draft water level to effectively utilize the head up to
Hs is raised to near the lower end of the water turbine runner 4 by adjusting the air introduction device 8. Furthermore, water and air mix to form bubbles within the water turbine runner 4, and a large amount of air is discharged from the draft pipe 5 to the water garden 6, resulting in negative pressure inside the water turbine casing 2. For this purpose, the water turbine casing 2 is provided with an air introduction device 8 for adjusting the draft water level to supply air into the casing 2. As shown in FIG. 3, when the water turbine is stopped, the air introducing device 8 uses a coil spring 13 installed between the air regulating valve 10 and the spring seat 12 to close the air regulating valve 1 with a constant force.
0 and the valve seat 9, and when the water turbine is operated and the inside of the water turbine casing 2 becomes negative pressure, the air regulating valve 1
0 and the spring seat 12 are simultaneously pushed down to the position of the imaginary line so that the atmosphere flows into the water turbine casing 2. In FIG. 3, reference numeral 11 is an adjustment bolt whose lower end is welded to the center of the air adjustment valve 10, and whose upper end is threaded. An adjustment bolt 11 is screwed into the center of the spring seat 12. 13 is a coil spring, which has a valve seat 9 and a spring seat 1.
2, and provides a force that constantly presses the air regulating valve 10 against the valve seat 9. A locking screw nut 14 is screwed onto the adjustment bolt 11 and prevents the adjustment bolt 11 and the spring seat 12 from loosening.

(C) Problems to be solved by the invention The conventional cross-flow turbine has the above-mentioned configuration, but when air flows into the turbine casing 2, the incoming air flows as shown by the arrow in Figure 3. pass through the gap between the spring wires of the coil spring 13 and change the direction.
It changes direction by 180 degrees and passes through the gap between the valve seat 9 and the air regulating valve 10, then changes its direction by 90 degrees and flows into the water turbine casing 2. In addition, the inflow air passage is formed by a coil spring 13.
When passing between the spring wires, the coil spring 13 is reduced in size.
It expands when it leaves the air, contracts when it passes through the gap between the valve seat 9 and the air adjustment valve 10, and expands when it leaves there. Such incoming air has a complicated flow, and Karman vortices, surging, etc. occur especially near the gap between the valve seat 9 and the air regulating valve 10, which causes large noise and causes the air regulating valve 10 to vibrate. The valve seat 9 and the air regulating valve 10 collide with each other, causing noise, and further abrading the contact surface between the valve seat 9 and the air regulating valve 10, shortening the service life. It had the following problems.

(D) Measures to solve the problem The valve seat has a conical inner wall, and an air inlet is provided in the valve seat to allow air to flow when it comes into contact with the inner wall of the valve seat. An air regulating valve is provided to stop the air and allow the air to flow when the water is released, and a pressure regulating device made of an elastic body is provided to press the air regulating valve against the valve seat, so that when the inside of the water turbine casing becomes negative pressure, the valve seat This solves the problems of the prior art by creating a gap between the air inlet and the air regulating valve to allow air to pass through the air inlet into the water turbine casing to prevent noise, vibration, etc.

(E) Embodiment FIG. 1 is a sectional view showing an embodiment of the present invention. In FIG. 1, a valve seat 90 is shaped like a bell with a wide base and has a conical inner wall. The valve seat 90 has a flange portion 90a at its bottom portion, and the flange portion 90a is fixed to the upper part of the water turbine casing 2 with bolts. In the embodiment shown in FIG. 1, the conical inner wall of the valve seat 90 is provided with two rows of 8s arranged at four equal intervals in the circumferential direction.
Air inlets 90b are provided. However, it is not limited to the inner wall side, and may be provided on the ceiling. Reference numeral 100 designates an air regulating valve, the outer peripheral side surface of which is conical so as to fit into the conical inner wall of the valve seat 90. Further, an air inlet 90b is located within the side surface of this conical shape, and a concave hole opening at the bottom is formed inside. A groove is machined in the lower part of the outer peripheral side of the air regulating valve 100, into which an O-ring 150 is fitted, and the lower end 100a is rounded to reduce air resistance. 130 is an elastic body such as a coil spring, which is installed inside the air regulating valve 100, and whose lower end is supported by the spring seat 120.
The lower end surface of the spring seat 120 is located inside the lower end surface of the air regulating valve 100. Reference numeral 110 denotes an adjustment bolt, the lower end of which is welded to the spring seat 120, the upper end formed with a thread, and screwed into the upper end of the valve seat 90. 140 is a locking butterfly nut,
After adjusting the spring pressure between the valve seat 90 and the air regulating valve 100, it is screwed onto the adjusting bolt 110 to prevent the adjusting bolt 110 from loosening. These adjustment bolts 11
0, a spring seat 120, an elastic body 130, a locking wing nut 140, and the like constitute a pressure adjustment device 160. Note that the elastic body 130 does not necessarily need to be provided inside the air adjustment valve 100, and may be provided, for example, between the upper part of the valve seat 90 and the wing nut 140. It is sufficient to apply a force to do so and to install it outside the air inflow path.

Next, to explain the operation, when the water turbine is stopped, the elastic body 130 applies a constant force to the valve seat 90 and the air adjustment valve 100.
is closed and sealed by an O-ring 150. When the water turbine is operated, the air regulating valve 100 is pushed down to the imaginary line by the negative pressure inside the water turbine casing 2, and the air regulating valve 100 is pushed down to the imaginary line, causing the valve seat 90 and the air regulating valve 10 to
A gap is created between the valve seat 90 and the air inlet 9 of the valve seat 90.
Atmospheric air is introduced into the water turbine casing 2 from 0b.
The force of the elastic body 130 and the negative pressure inside the water turbine casing 2 are balanced, and the pressure inside the water turbine casing 2 can be kept constant.

(F) Effect of the invention As described above, the present invention provides an air regulating valve 100 in the valve seat 90 having a conical inner wall, which adjusts the inflow of air by coming into contact with and separating from the inner wall of the valve seat 90, and this air regulating valve. 100 is configured to be pressed against the inner wall of the valve seat 90 by a pressure adjustment device 160 that can adjust the pressing force, so that the air introduced from the air introduction port 90b is applied to the air adjustment valve 100 disposed inside. Since the elastic body 130 is provided outside the air flow path, the flow of air cannot be prevented by the elastic body 130, and when air is introduced into the water turbine casing 2. Karman vortices, surging, etc. are less likely to occur, and accompanying noise and vibration can be prevented from occurring. Furthermore, the air introduction device of the prior art has a configuration in which the air adjustment valve 100, the spring seat 120, and the adjustment bolt 110 move, but in the present invention, only the air adjustment valve 100 moves, so stable air adjustment can be maintained. . Furthermore, in the present invention, the flow passage in the gap between the valve seat 90 and the air regulating valve 100 is lengthened in the direction of movement of the air regulating valve 100 to increase the flow resistance, thereby eliminating vertical vibration of the air regulating valve 100. , valve seat 90 and air regulating valve 10
This has various excellent effects, such as eliminating collisions with zero, reducing noise, reducing wear, and extending life.

[Brief explanation of drawings]

Figure 1 is a sectional view of the air introduction device of the present invention, Figure 2 is a sectional view of the air introduction device of the present invention.
The figure is a schematic configuration diagram of a cross-flow water turbine, and FIG. 3 is a sectional view of a conventional air introduction device. 2 is a water turbine casing, 90 is a valve seat, 90b is an air inlet, 100 is an air adjustment valve, 130 is an elastic body, and 160 is a pressure adjustment device.

Claims (1)

[Scope of utility model registration request] A valve seat having a wide conical inner wall and having a lower end opening fixed to the upper part of the water turbine casing, an air inlet bored in the valve seat, and an air inlet that is freely joined to the inner wall of the valve seat. A cross-flow water system comprising: an air adjustment valve that adjusts the inflow of air; and a pressure adjustment device made of an elastic body that is attached to the valve seat and presses the air adjustment valve against the inner wall of the valve seat. Air introduction device for cars.