EP0035247A2

EP0035247A2 - Lateral seal for collapsible dams

Info

Publication number: EP0035247A2
Application number: EP81101409A
Authority: EP
Inventors: Arturo Colamussi; Vittorio Merli
Original assignee: Pirelli Furlanis Applicazioni Idrauliche Agricole Gomma SpA
Current assignee: Pirelli Furlanis Applicazioni Idrauliche Agricole Gomma SpA
Priority date: 1980-02-29
Filing date: 1981-02-26
Publication date: 1981-09-09
Also published as: EP0035247A3; IT8020250A0; JPS56135614A; IT1140723B

Abstract

The subject matter of the present invention is a lateral seal for collapsible dams (1 or 15) of the type which comprises at least one metallic tank (2 or 16) hinged to the bottom of a waterway and which oscillates around the said hinge (6 or 17), where said lateral sealing comprises ledge means in the area of the lateral walls of the waferway.

Description

The present invention refers to a lateral seal for collapsible dams, and in particular to a lateral seal for collapsible dams of the type comprising at least one rigid element hinged at one of their ends to the bottom of the waterway inside of which the dam is arranged.
There exist known collapsible dams of the previously defined type which have as a lateral sealing element sealing strips for example of rubber which when the rigid element rotates around the axis on which it is arranged, slide on the surface on the side of the waterway.
However, this type of lateral seal for collapsible dams presents the drawback of wearing-out the sealing strips as well as of acting as a brake for the movement of the rigid lateral element or elements hinged to the bottom of the waterway, particularly for dams having limited overall dimensions.
The aim of the present invention is to provide a lateral seal for collapsible dams of the previously defined type which is durable, which increases its sealing capacity when the pressures exercised by the water on the collapsible dam itself increase, and which can be controlled so as to provide the sealing in any raised position assumed by the dam itself.
One object of the present invention is a lateral seal for collapsible dams of the type comprising at least one rigid element hinged at one of their ends to the bottom of a respective waterway, characterized by the fact of comprising ledge sealing means on the lateral walls of the waterway.
The present invention will be better understood from the following detailed description, made by way of a non limiting example, with reference to the attached sheets of drawings, wherein:

- Figure 1 shows a perspective view of a collapsible dam provided with lateral sealing means according to the present invention:
- Figure 2 shows a perspective view of a large size collapsible dam provided with lateral sealing means according to the present invention;
- Figures 3 and 4 show in cross-section two types of sealing strips that can be associated to the lateral sealing means according to the present invention.

In the more general idea of solution of a lateral seal for collapsible dams of the type comprising one or several rigid elements hinged at one of their ends to the bottom of a waterway, said lateral seam is provided by means of a ledge sealing means.
In Figure 1 there is shown a perspective view of a collapsible dam 1, provided with lateral sealing means according to the present invention.
Said collapsible dam 1 comprises a rigid element 2, formed for example by a metallic tank into which air can be introduced for causing it to float and to raise it with respect to the upstream water basin 3 formed by the dam 1 itself.
Said rigid element 2 is connected along its end 4 by a hinge 6 to the bottom 5 of the waterway.
The seal between the side edges 7 of the rigid element 2 (only one can be seen in Figure 1) and the lateral walls 8 and 9 of the waterway, is provided by means of a ledge sealing means.
Said ledge sealing means in the particular embodiment represented in Figure 1 and applicable in particular to collapsible dams having limited overall dimensions, can oscillate around an axis parallel to the axis of the hinge 6 which connects the rigid element 2 to the bottom 5 of the waterway.
Said ledge sealing means comprises in the embodiment represented in said Figure 1, a rigid and preferably metallic L-shaped bar lo, hinged at its end 11 to an axis parallel t& the axis of the hinge 6. In particular, as shown in the Figure, the said two axes can coincide.
As an alternative, said bar lo can be hinged to the bottom 5 of the waterway by means of a ball joint (not shown in the Figures).
Said ledge sealing means comprises moreover blind threaded holes 12 present in the lateral sides 8 and 9 of the waterway, so that bolts 13, associated to said bar lo, can be engaged through the holes present on the side of said bar lo facing the lateral sides 8 and 9 of the waterway.
As an alternative to blind threaded holes 12 and bolts 13 a hydraulic-jack (not shown) can be connected to the bar lo for varying the position of said bar lo on the lateral sides 8 and 9 of the waterway.
Said ledge sealing means lo can also be seen in detail in Figure 3, where is shown a type of gasket that can be applied to said ledge sealing means.
In the particular embodiment shown in said Figure 3, said gasket is a labyrinth seal 14 comprising a series of staggered grooves and projections present on the facing surfaces of the rigid bar lo and of the side edge 7 of the rigid element 2.
As an alternative to the solution shown in Figure 3, said gasket can be formed by one or several continuous elements of elastomeric material or by one or several inflatable seals, always of elastomeric material.
In Figure 2 there is shown a large size collapsible dam 15 for great depths, comprising one or more rigid elements 16, connected at one of their ends 17, by a hinge 18, to the bottom 19 of the waterway.
Said rigid elements 16 comprise air tanks 2₀, into which can be introduced air for causing them to be lifted from their seat 21 found in the bottom 19 of the waterway, which seat 21 is suitable to receive said rigid elements 16 when the collapsible dam 15 is in its collapsed position.
A sheet 22, for example of a rubberized fabric, closes the opening that exists between the upper lip 21' of the seat 21 and the upper edge 23 of the rigid elements 16, for preventing any eventual sediment from settling in said seat 21, when the collapsible dam 15 is raised.
Said rigid elements 16 are connected to each other in a water-tight manner by sealing elements 24 formed for example by appropriate gaskets or rubberized fabrics.
The lateral seal between said rigid elements 16 and the banks 25 of the waterway comprises ledge sealing means.
Said means comprise in the particular embodiment represented in Figure 2 a shoulder 26, projecting from the lateral bank 25 of the waterway, itself,, which is contacted by the lateral edge 27 of the rigid element 16 adjacent to the said lateral bank 25 of the waterway.
Said ledge sealing means can comprise gaskets (see Figure 4) such as for example one or more'continuous sealing strips 28 of elastomeric material, present either on the surface of shoulder 26 facing the rigid element 16, or on the surface of the lateral edge 27 of rigid element 16 facing the said shoulder 26, or on both of the said facing surfaces.
As an alternative to said continuous sealing strips 28 there can be either a labyrinth-type seal, such as the one shown in Figure 3, or an inflatable gasket of elastomeric material.
For collapsible dams having large dimensions and for great depths such as those represented in Figures 2, said rigid elements 16 can be connected to the bottom of the waterway by tie rods, so as to limit the amplitude of the raising oscillations, in order not to stress sheet 22.
Said tie rods comprise in the particular embodiment shown in said Figure 2, chains 29 for example in two rows connected at one end to the bottom of the seat 21 and at the other end to said rigid elements 16.
As can easily be understood from the previous descpript- ion, the lateral sealing means for collapsible dams according to the present invention achieves the above mentioned aims.
In fact, the solution represented in Figures 1 and 3, allows small sized collapsible dams provided with the lateral sealing means according to the present invention, to effect the sealing for any position assumed by the dam itself, since said ledge sealing means can also be raised or lowered, as desired.
Moreover the collapsible dams provided with sealing means according to the present invention increase their own sealing capacity, just as the head of water in the basin 3 upstream is increased, since the thrust that the water exercises upon the dam (see arrow in Figure 1) is unloaded on the ledge sealing means, increasing, as a consequence, the pressure exercised between the side edges of the rigid element and the ledge sealing means themselves.
Moreover, since during the raising and lowering of the rigid elements constituting the dam itself, there occurs no sliding of the sealing means and the gasket against the surfaces, there is eliminated any wearing-out of the said sealing means and the gaskets.
The solution represented in Figures 2 and 4 also guarantees for large dimension collapsible dams 15 provided with sealing means according to the present invention, an efficient seal even if the pressure that the water exercises on the dam itself, increases (see arrow of Figure 2).
In fact, the increase in the thrust of the water also increases the pressure that the lateral rigid elements 16 exercise against the shoulder 26 present on the banks 25 of the waterway.
Moreover the tie rods which connect the rigid elements 16 to the bottom of the seat 21 and which are received by the seat 21 if the rigid elements 16 lie on the bottom, prevent in particular overturning of the rigid elements 16 not adjacent to the banks 25 of the waterway in case of very high water thrusts besides maintaining the sheet 22 which protects--said seat 21 free from any stress.
What is more, both the solutions represented permit the collapsible dam to support differences in depths, even from the side where there is the hinge that connects the rigid element of the collapsible dam to the bottom of the waterway (i.e. from the direction opposite to that indicated by the arrows in Figures 1 and 2).
In fact, the upward thrust resulting from the air present in the air tanks of the rigid elements, can compensate the pressure exercised on the dam by the higher water level present on the side of the collapsible dam where said dam is hinged.
Moreover for the dam represented in Figures 1 and 3 the resistance also to great differences in depth, opposed to those indicated by the arrows of Figure 1, can be obtained by rendering the bar lo fast with the rigid element 2, and effecting the seal between the bar lo and lateral side 8 or 9 of the waterway with the eventual interpositioning of gaskets.
Although several particular embodiments of a lateral seal for collapsible dams according to this invention have been illustrated and described, it is understood that also included in its scope are any other alternative embodiments accessible to a technician of this field.

Claims

1. Lateral seal for collapsible dams of the type comprising rigid elements hinged at one of their ends to the bottom of a waterway into which the dam itself has been placed, characterized by the fact of comprising ledge sealing means (lo or 26) in the area of the lateral walls (8, 9 or 25) of the waterway.

2. Lateral seal for collapsible dams according to claim 1, characterized by the fact that said ledge sealing means (lo) can oscillate around the axis (6) at which the rigid elements (2) of the dam itself are hinged.

3. Lateral seal for collapsible dams according to claims 1 and 2, characterized by the fact that said sealing means comprise an L-shaped bar (lo) hinged at one end blind threaded holes (12) in the lateral walls (8, 9) of the waterway, and bolts (13) associated to said bar engageable in said holes.

4. Lateral seal for collapsible dams according to claim 1, characterized by the fact that said lateral ledge sealing means (26) are fixed.

5. Lateral seal for collapsible dams according to claim 4, characterized by the fact that said ledge sealing means comprise a shoulder (26) projecting from each lateral wall (25) of the waterway.

6. Lateral seal for collapsible dams according to claims 1, 4 or 5, characterized by the fact that the said rigid-elements hinged at one of their ends are associated tie rods (29) for limiting their oscillating movement.

7. Lateral seal for collapsible dams according to any of the preceding claims, characterized by the fact that said ledge sealing means comprise gaskets (14 or 28).