JP4427427B2 - Flexible membrane undulation weir - Google Patents

Description

  The present invention relates to a flexible membrane undulation weir provided in a water channel.

  In general, there is known a flexible membrane undulation weir that is provided across a water channel and dams the water channel so that it can be opened.

  In this type of flexible membrane type undulation weir, the edge of the flexible membrane is fixed to the bottom of the water channel to form a bag, and when the fluid is supplied to the inside, it expands to take a standing posture. When the fluid inside is discharged, it contracts and takes a lying posture.

  Specifically, as shown in FIG. 5 (a), the flexible membrane type undulation weir takes an upright posture inclined toward the downstream side (for example, Patent Documents 1 and 2) 50, and FIG. As shown in (b), a device 60 having a fin F on its surface while taking a standing posture similar to the above is known.

In these movable membrane type undulation weirs, the weir height H in the standing posture is set in advance, and when the water level exceeds the weir height H, an amount of water corresponding to the water level flows out.
JP-A-56-414 JP 56-415

  However, in the flexible membrane type undulation weirs 50 and 60, water flow exceeding the weir height H (hereinafter referred to as overflow) causes so-called weir body vibration in which the flexible membranes 51 and 61 vibrate. .

  That is, since the standing posture of the flexible membrane type undulation weir 50 is inclined to the downstream side, the overflow overflows from the flexible membrane 51 at the separation point 52 and falls to the bottom of the water channel. However, the air pocket S1 is formed between the flexible film 51 and the overflow due to the separation of the overflow. Since the air pocket S1 has a negative pressure due to overflow (Bernoulli's theorem), the flexible membrane 51 receives a force in the expanding direction. The negative pressure increases and decreases with changes in the position of the separation point 52 that changes according to the flow velocity of the overflow, and changes in the energy of the overflow itself, so that the force applied to the flexible film 51 increases and decreases. As a result, weir vibration occurs.

  On the other hand, in the flexible membrane type undulating weir 60, although the separation point 62 is always constant by the fin F, an air pocket S2 is formed between the overflow and the flexible membrane 61. A weir body vibration is generated by a pressure change in the air pocket S2 according to its own energy change or the like.

  Furthermore, in the flexible membrane type undulation weirs 50 and 60, since an overflow is formed from the separation points 52 and 62 to the bottom of the water channel, the overflow and the bottom of the water channel or the water surface The impact noise, that is, the falling water noise was generated.

  This invention is made | formed in view of the said subject, and it aims at providing the flexible membrane type undulation weir which can suppress generation | occurrence | production of a weir body vibration and falling noise.

In order to solve the above problems, the present invention has a flexible membrane that is fixed to the bottom of a water channel and that defines a fluid storage chamber between the bottom and supplying fluid to the fluid storage chamber. A flexible membrane type weir that takes a standing posture while taking a lying posture by discharging a fluid, and is downstream of a flexible membrane disposed downstream of a water channel in the standing posture further comprising a support portion for supporting the part, the support part is in the upright position, so as to maintain the rising angle of the downstream side opening into the fluid housing chamber side between the bottom and the downstream side at an acute angle The flexible membrane is made of rubberized cloth, and the support part is made of a branched part that branches from the rubberized cloth in the thickness direction and is connected to the bottom of the water channel in the liquid storage chamber. is there.

In the flexible membrane type undulation weir, it is formed between the bottom portion and the downstream side portion of the water channel, so that the fluid storage chamber is formed in a film shape that divides the chamber into two chambers, and these chambers communicate with each other. It is preferable to have a through hole .

In the flexible membrane undulation weir, it is preferable that the rising angle is set to 30 ° or less .

  According to the present invention, the support portion can maintain the rising angle of the downstream side portion in the standing posture (opening angle toward the fluid storage chamber) at an acute angle, and therefore, the downstream downstream smoothly with respect to the bottom portion of the water channel. Overflow along the outer surface of the side can be formed.

  Therefore, in this invention, it can prevent that an air pocket is formed between an overflow and a flexible film | membrane, and can suppress generation | occurrence | production of the weir body vibration resulting from the said air pocket.

  Furthermore, in the present invention, an overflow that gently enters the bottom or the water surface can be formed along the outer surface of the downstream side portion, so that the occurrence of waterfall noise can be suppressed.

  The “rising angle of the downstream side portion in the standing posture” is a rising angle of the downstream side portion in a state where water pressure is applied from the upstream side to the flexible membrane.

In the present invention, since the bottom portion and the downstream side of the fluid housing chamber is connected by the supporting portion, by water pressure from the upstream side to the downstream side to be inclined to the downstream side than the downstream portion Can also be retained by a support fixed on the upstream side.

  According to the configuration in which the support portion is formed in a film shape and has a through hole, the longitudinal direction of the downstream side portion (the direction crossing the water channel) while allowing the fluid to flow through the through hole and the entire fluid storage chamber. The downstream side portion and the bottom portion can be connected to each other over a wide range along the line by the membrane-like support portion, thereby increasing the connection strength between them. Therefore, even when strong water pressure is applied, the downstream side portion can be supported more reliably.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side sectional view showing a state in which a flexible membrane type weir according to an embodiment of the present invention is in a standing posture, and FIG. 2 is a diagram in which the flexible membrane type weir in FIG. 1 is in a lying posture. FIG. 3 is a perspective view showing the flexible membrane-type undulation weir in FIG. 1 with a part thereof omitted.

  With reference to each figure, the flexible membrane-type undulation weir 1 is fixed to the bottom B of the water channel W so as to cross the water channel W (along a direction perpendicular to the paper surface of FIG. 1). A pipe G capable of injecting and discharging a predetermined fluid (for example, air) is formed on the bottom B. The flexible membrane undulation weir 1 takes a standing posture as shown in FIG. 1 when a fluid is supplied from the pipe G, and takes a lying posture by discharging the fluid from the pipe G. ing.

  Further, the flexible membrane-type undulating weir 1 maintains the rising angle R of the front branching portion 4 that opens to the fluid storage chamber 7 between the bottom B and the front branching portion 4 in the above-mentioned standing posture at an acute angle. Can be done. Hereinafter, a specific configuration of the flexible membrane type undulation weir 1 will be described.

  The flexible membrane type undulation weir 1 includes a belt-like rubberized cloth 2. The rubberized cloth 2 is formed into a thick portion 3 and a front branch portion 4 and a back branch portion 5 branched from the thick portion 3 into two in the thickness direction.

  The rubberized cloth 2 is arranged on the bottom B so that the long side edge 2a of the thick part 3 is upstream of the pipe G and the long side edge 2b of the front branch 4 is downstream of the pipe G. Has been. A presser foot 6 is placed on each of the long edge portions 2a and 2b. The presser foot 6 includes an anchor bolt provided on the bottom portion B and a nut screwed to the anchor bolt (both not shown). Etc., respectively.

  Furthermore, both ends in the longitudinal direction of the rubberized cloth 2 are airtightly fixed to the side walls of the water channel W (not shown), and thereby, between the rubberized cloth 2 and the bottom B of the water channel W. The fluid storage chamber 7 is partitioned.

  On the other hand, the long side edge 2c of the back branching part 5 is fixed to the bottom B via the presser foot 6 on the upstream side of the long side edge 2b. That is, the back branching portion 5 is arranged so as to partition the fluid containing chamber 7 into two chambers 7a and 7b. The back branching portion 5 has a plurality of chambers 7a and 7b communicating with each other. A slit 8 is formed. As shown in FIG. 4, the slits 8 are inverted V-shaped cuts extending from the long side edge 2c.

  Hereinafter, the operation of the flexible membrane type undulation weir 1 will be described.

  When fluid is injected from the pipe G into the fluid storage chamber 7, as shown in FIG. 1, the rubberized cloth 2 expands and assumes a standing posture. In this standing posture, when the weir height H is defined by the apex T of the rubberized cloth 2, that is, when the water level L exceeds the weir height H, an overflow E exceeding the rubberized cloth 2 is generated. Become.

  Further, in the standing posture, the front and back branch portions 4 and 5 are disposed downstream of the vertex T. That is, the thick wall portion 3 and the front branching portion 4 arranged on the downstream side of the vertex T constitute the downstream side portion in the present embodiment.

  In the standing posture, the rubberized cloth 2 is inclined to the downstream side due to the water pressure from the upstream side, but the front branching portion 4 is fixed to the bottom B by the back branching portion 5. Therefore, the rising angle is maintained at an acute angle R.

  That is, the front branching portion 4 is gently continuous to the bottom B along the water flow direction, and an overflow E flowing along the outer surface of the front branching portion 4 is formed. Therefore, in the flexible membrane type undulation weir 1, it is possible to suppress the formation of an air pocket between the overflow E and the front branching portion 4, so that the rubberized cloth 2 vibrates. The situation (weir body vibration) can be suppressed. Furthermore, in the flexible membrane type undulation weir 1, since the overflow E along the front branching portion 4 can be formed, the overflow E can be prevented from abruptly entering the bottom B or the water surface. Therefore, it is possible to suppress the occurrence of falling water noise.

  In the present embodiment, the rising angle R is set to about 60 °, but is not limited to 60 °, and may be at least less than 90 ° (acute angle). From the viewpoint of preventing the occurrence of falling water noise, it is more preferably 30 ° or less.

  On the other hand, by making the rising angle R relatively large, there is also an advantage that the width dimension Wd (see FIG. 1) required for installing the flexible membrane type undulation weir 1 can be reduced. Specifically, when the rising angle R is about 60 ° as in the above embodiment, the width Wd can be made smaller than twice the weir height H, so that the compact flexibility It can be set as the membrane type undulation weir 1.

  That is, the rising angle R can be appropriately selected from an angle (acute angle) of less than 90 ° according to the installation space of the flexible membrane-type hoisting weir 1 and the like.

  When the fluid in the fluid storage chamber 7 is discharged from the pipe G, as shown in FIG. 2, the rubberized cloth 2 contracts according to the water flow in the water channel W, and the weir is opened.

  As described above, according to the flexible membrane-type undulating weir 1, the rising angle R of the front branching portion 4 in the standing posture can be maintained at an acute angle by the back branching portion 5. An overflow E can be formed along the outer surface of the front branching portion 4 that is gently continuous with the bottom B.

  Therefore, in the flexible membrane type undulation weir 1, it is possible to prevent an air pocket from being formed between the overflow E and the rubberized cloth 2 (the front branching portion 4). The occurrence of dam body vibration can be suppressed.

  Furthermore, in the flexible membrane type undulation weir 1, it is possible to form the overflow E that gently enters the bottom B or the water surface along the outer surface of the front branching portion 4. Can be suppressed.

  According to the configuration in which the bottom B in the fluid storage chamber 7 and the front branching portion 4 are connected by the back branching portion 5, the front branching portion 4 that is inclined to the downstream side by the water pressure from the upstream side is It can be stopped by the back branching portion 5 fixed upstream of the branching portion 4.

  According to the configuration in which the back branching portion 5 is formed in a film shape and the slit 8 is provided, the longitudinal direction of the front branching portion 4 (FIG. 1) while fluid is circulated through the slit 8 and the entire fluid storage chamber 7. The front branching portion 4 and the bottom B can be connected to each other by the back branching portion 5 over a wide range along the direction perpendicular to the paper surface, thereby increasing the connection strength between them. Therefore, even if a strong water pressure is applied, the front branching portion 4 can be supported more reliably.

It is side surface sectional drawing which shows the state by which the flexible membrane type undulation weir based on embodiment of this invention was made into the standing posture. It is side surface sectional drawing which shows the state by which the flexible film type | formula undulation weir of FIG. It is a perspective view which abbreviate | omits and shows a part of flexible membrane type undulation weir of FIG. It is a front view which shows the slit of FIG. It is side surface sectional drawing which shows the structure of the conventional flexible membrane type undulation weir.

Explanation of symbols

1 Flexible membrane type undulation weir 2 Rubberized cloth (flexible membrane)
4 Front branch part 5 Back branch part (support part)
7 Fluid storage chambers 7a, 7b chamber B bottom R rising angle W water channel

Claims (3)

By having a flexible membrane that is fixed to the bottom of the water channel and that divides the fluid storage chamber between the bottom and taking a standing posture by supplying fluid into the fluid storage chamber, and by discharging the fluid A flexible membrane undulation dam designed to take a lying posture,
A support portion for supporting the downstream side portion of the flexible membrane disposed on the downstream side of the water channel in the standing posture;
The support portion is configured to maintain the rising angle of the downstream side portion that opens to the fluid storage chamber side between the bottom portion and the downstream side portion at an acute angle in the standing posture ,
The flexible membrane is made of rubberized cloth,
The flexible membrane-type undulation weir is characterized in that the support portion includes a branch portion branched from the rubberized cloth in the thickness direction and connected to the bottom portion of the water channel in the liquid storage chamber . The support portion is provided between the bottom portion and the downstream side portion of the water channel so as to be formed in a film shape that divides the fluid storage chamber into two chambers, and includes a through hole that communicates these chambers. The flexible membrane-type undulating weir according to claim 1. The flexible membrane type undulation weir according to claim 1 or 2, wherein the rising angle is set to 30 ° or less.

Images