JPH0118677Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a water lock for underground drainage. In general, in rice fields, surplus water must be removed through culverts in the winter to lower the groundwater level and dry the ground surface, or the flow within the culverts must be stopped and the water level adjusted during the irrigation season. Horizontal locks, head locks, overflow locks, and the like are known as locks used for such purposes. Piston type and valve type are mainly known as the water stop mechanism which is the main part of these water locks. These are illustrated in Figure 1 a, b, c and Figure 2 a, b, c. In other words, Fig. 1 shows the valve system, Fig. 1a shows the valve system for the horizontal lock, Fig. 1b shows the valve system for the head lock,
Figure 1c shows the valve system for an overflow lock, where 1 is the culvert 1 and 2 is the valve. Figure 2 shows the piston system, Figure 2a shows the piston system for horizontal locks, Figure 2b shows the piston system for head locks, and Figure 2c shows the piston system for overflow locks. It's a piston. Each of these water locks has its advantages and disadvantages, but a piston-type water stop mechanism causes sediment to accumulate in the recess 1a at the bottom, resulting in poor sweeping performance and functional problems, whereas a valve-type water stop mechanism has problems. Since there are no recesses in the bottom, it has good sweeping properties and also has a good water-stopping function. However, for example, in the case of a horizontal water lock using the valve system, as shown in FIG. is high or the inner diameter is large, large water pressure acts on the valve body 2a, and the valve body 2a
It becomes difficult to operate when a is fully open. The present invention was devised in view of the above circumstances, and its purpose is to provide a water lock for underdrain drainage whose valve body can be opened with a small force. Embodiments of the present invention will be described below with reference to FIG. 4 and subsequent figures. Figure 4 is an overall sectional view, and culvert 10 is paddy field 1.
An outer tube 12 is vertically connected to a part of the outer tube 1, and a cap 13 is provided at the upper end of the outer tube 12. Reference numeral 14 denotes a valve body made of a rubber body, which is provided diagonally in close contact with a part of the underdrain 10 and a part of the outer cylinder 12, and closes the upstream side 10a and the downstream side 10b, and also serves as a valve body. A hole 15 is formed in the center of the body 14, and an inner tube 16 is fixed around the hole 15. A piston 17 is fitted into the inner cylinder 16 so as to be vertically slidable, and a rod 18 serving as an operating rod is integrally provided on the piston 17. It extends and projects upward from the cap 13, and an operating handle 19 is provided at the projecting end. A drainage hole 20 is formed at a position of the rod 18 near the piston 17.
It opens at the lower end surface 17a of. Reference numeral 21 denotes a water-stopping rubber ring provided between the rod 18 and the upper hole 16a. As shown in FIG. 4, when the valve body 14 is closed, water enters the upstream side 10a of the culvert and the outer cylinder 12 up to the same water level as the paddy field 11, and the valve body 14 is H×S.
×P is pressed downward by the force W. H is the water level, S is the pressure receiving area of the valve body 14, and P is a coefficient. Here, the inner diameter D of the outer cylinder 12 is 50 mm, 80 mm, and 300 mm.
mm, and the water level of the outer cylinder 12 is 100 cm and 120 cm, the force W in the table below acts on the valve body 14.

[Table] Since such a large force W acts, the valve body 14
It is very difficult to open directly. On the other hand, according to the embodiment, when the valve body 14 is fully opened to adjust the water level during irrigation or to drain water in winter, the rod 18 is moved upward by holding the operation handle 19, as shown in FIG. the drain hole 20 to face the inside of the outer cylinder 12. At this time, since no force due to water pressure acts on the rod 18, it can be pulled up smoothly with a light force. As a result, the water in the outer cylinder 12 is drained from the drain hole 20 and the hole 15 of the valve body 14 to the downstream side 10b of the underdrain 10, and the water level decreases from H to h, so that the above-mentioned force acting on the valve body 14 W decreases. After this, the rod 18 is further pulled up, the piston 17 is brought into contact with the inner cylinder 16, the valve body 14 is pulled up together with the inner cylinder 16, the upstream side 10a and the downstream side 10b of the underdrain 10 are directly communicated, and the valve body 14 is brought up. is fully opened. At this time, the force for pulling up the valve body 14 becomes small, and the valve body 14 can be pulled up easily. In this way, the valve body 14 can be pulled up and fully opened with a very light force, so the operation of fully opening the valve body 14 can be made extremely simple. The present invention is as described above, and when the rod is slid downward and the valve body 14 closes the upstream and downstream sides of the underdrain 10, the drainage hole 20 formed in the rod opens into the inner cylinder 16, so that the upstream The inside of the inner cylinder 16 is cut off from the inside of the outer cylinder 12 communicating with the side 10a, and the upstream side 10 of the underdrain 10
a and the downstream side 10b can be reliably closed. When the rod is slid upward by a predetermined stroke from the above-mentioned state, the drainage hole 20 opens into the outer cylinder 12, and the water in the upstream side 10a of the underdrain 10 flows into the outer cylinder 12 and into the drainage hole 2.
0, the water flows out from the inner cylinder 16 and hole 15 to the downstream side 10b, and the water level in the outer cylinder 12 is lowered to the position where the drainage hole 20 is, reducing the force acting on the valve body 14.
After this, by moving the rod upward, the valve body 14 is moved upward with a light force along with the inner cylinder 16, and the underdrain 10 is moved upward.
The upstream side 10a and downstream side 10b of can be communicated. Therefore, the valve body 14 can be smoothly moved upward with a light force to connect the upstream side 10a and the downstream side 1 of the culvert 10.
0b can be fully opened with a simple operation.

[Brief explanation of drawings]

Fig. 1 a, b, c and Fig. 2 a, b, c are cross-sectional views of the conventional example, Fig. 3 is a diagram illustrating defects in the conventional example, Fig. 4 is a cross-sectional view showing the embodiment of the present invention; 5 and 6 are operation explanatory diagrams. 10 is a culvert, 10a is an upstream side, 10b is a downstream side, 14 is a valve body, 15 is a hole, and 18 is a rod.

Claims (1)

[Scope of utility model registration request] An outer cylinder 12 is vertically connected to the middle of the underdrain 10 in the longitudinal direction, and a valve body 14 for opening and closing the upstream side 10a and the downstream side 10b of the underdrain 10 is installed along the outer cylinder 12 at the connection part of the outer cylinder 12. The upstream side 10a of the underdrain 10 is provided on the valve body 14 so as to be movable up and down.
and the downstream side 10b, and an inner cylinder 16 is installed around the hole 15, and the lower part of the rod is fitted into the inner cylinder 16 so as to be relatively slidable up and down by a predetermined stroke. In addition, the upper part of the rod protrudes upward from the outer cylinder 12, and a drainage hole 20 is formed in the lower part of the rod, extending from the lower end surface to the circumferential surface, so that when the rod is slid downward by a predetermined stroke, the drain hole 20 is inserted into the inner cylinder 16. A water lock for underdrain drainage, characterized in that it is opened and is formed so as to open into an outer cylinder 12 when the rod is slid upward by a predetermined stroke.