Title of Invention

A SWING GATE FOR REGULATING OUTFLOW OF WATER FROM TIDAL REGULATORS

Abstract

The fluctuation of sea water level between low tide and high tide causes ingress of saline water into the river near its junction with the sea. Whenever the high tide level is above the water level in the river, the sea water travels upto several kilometers inside the river and makes the adjacent land saline and unfit for crop cultivation. Tidal regulators are constructed near the junction of river & sea to overcome this problem. These regulators consist of a concrete or masonry weir, with electrically operated vertical lift or radial gates. The gates are normally kept in closed position, so that the sea water does not enter the river during high tide. When there is flood in the river, the gates are opened with electrically operated hoists to enable flood waters to pass out to the sea. Daily monitoring of river water and sea water levels needs to be done during monsoons to decide the timing and extent of gate operation. The present invention solves this problem by automatically excluding the possibility of sea water ingress, obviating the need for electricity for operation of gates, and also by eliminating the need for monitoring of sea and river water levels. The present invention comprises of a gate that swings about a horizontal axis with its hinges near the top end of the gate. The upstream or river side water exerts an opening moment on the gate while the sea water on downstream exerts a closing moment on the gate, simultaneously. Whenever the river water level is above the sea water level, the gate automatically opens and allows the river water to flow into the sea. Whenever the river water level is lower than the sea water level, the gate automatically closes and prevents entry of sea water into the river. The gate can also be manually closed or opened by means of a hydraulic hoist, to enable maintenance works like rubber seal changing and painting etc. The novelty of the invention lies in the use of the water pressure as the actuating force to open or close the gate automatically, obviating the need for electricity for its operation. The differential water pressure caused by different water levels in the river and sea, automatically determines whether the gate should swing towards opening direction or closing direction. It also acts like a one way valve by preventing entry of sea water into the river as long as the water level in the river is below the sea water level. Another novelty of the invention lies in the use of a special design of the hydraulic hoist to enable its manual operation. The third novelty of the invention lies in the use of a by pass tube and a check valve in the hydraulic hoist to allow automatic operation of the gate or to lock the gate in closed, partially open or fully open position.

Full Text

FORM 2 THE PATENTS ACT 1970 (39 of 1970) THE PATENTS RULES, 2003 COMPLETE SPECIFICATION (Refer Section 10, Rule 13) AN AUTOMATIC SWING GATE GODBOLE PRASHANT PRABHAKAR AN INDIAN NATIONAL 2/B, BUTY PLOTS, DHARAMPETH, NAGPUR-440010, MAHARASHTRA STATE, INDIA. The following specification particularly describes the invention and the manner in which it is to be performed. 1 This invention relates to tidal regulators which are constructed at the junction of river and sea to prevent entry of sea water into the river during high tides. The ingress of sea water inside the river makes the adjacent land saline and unfit for cultivation. Presently the tidal regulators, which consist of concrete or masonry weirs are provided with electrically operated vertical lift or radial gates. The gates are normally kept in closed position so that the sea water does not enter the river during high tide. When there is flood in the river, the gates are opened with electrically operated hoists to enable flood waters to pass out to the sea. Daily monitoring of river water and sea water levels is therefore absolutely necessary during monsoons to ensure correct timing and extent of gate operation. This task is not only tedious, but also poses extra risk to the structure as failure of electricity, which may lead to delayed or non operation of gates can cause over- topping of tidal regulator itself and also cause flooding of villages & towns immediately on upstream side. The present invention proposes to solve this problem by providing an automatic gate which prevents entry of sea water into the river but allows passage of river floodwaters to sea. This automatic gate, which does not need electricity for its operation, also obviates the need for continuous monitoring of sea & river water levels during monsoons. The principal objective of this invention is to act as an automatic or self regulated barrier for preventing entry of sea water to the river during high tides, when sea water level is higher than river water level. Another objective of this invention is to allow passage of floodwaters to the sea, whenever there are floods in the river and river water level rises above sea water level. 2 A further objective of this invention is to function without the need of electricity. Accordingly, the invention provides a top hinged swing type gate for use on tidal regulators and similar structures like weirs and barrages, which (i) normally remains in closed position and prevents entry of sea water into river when sea water level is higher than river water level and (ii) automatically swings open during floods when river water level rises above sea water level, to allow passage of floodwaters to the sea. The invention is now described herein with the help of Figures 1A ,1B & 1C (on sheet no.1), Figure 2 (on sheet no.2), Figure 3 (on sheet no.3), Figure 4 (on sheet no.4) and Figure 5 (on sheet no.5). FIG.1A is a diagrammatic representation of the Swing Gate in sectional side elevation, in its closed position. The figure shows that the upstream or river side water level is lower than downstream or sea side water level, representing a high tide condition. Fig.1B is a diagrammatic representation of the Swing Gate in sectional side elevation, in its partially open position. The figure shows a small flood condition, where river water level is above sea water level. Fig.1C is a diagrammatic representation of the Swing Gate in sectional side elevation in fully open position. The figure shows a high flood condition, where river water level is above sea water level. In all the above 3 figures, the direction of flow is shown as that from upstream or river side to downstream or sea side. 3 As shown in Figures 1A, 1B & 1C, the gate consists of the following main components :- 1. A rotating gate leaf marked 'a' 2. A pair of trunnion girders marked 'b' embedded in RCC piers (shown by dotted lines). 3. Hoisting system marked 'c' & 4. Sealing system marked 'd'. Figure '2' (on sheet no.2) shows the subcomponents of the gate leaf, which comprises of: 1. A pair of hubs marked'1' 2. A pair of bush bearings marked '2' 3. A pair of end girders marked '3' 4. Horizontal girders marked '4' 5. Upstream and Downstream skin plates marked '5' 6. Counter weight market '6', which is provided inside the cavity of gate leaf, formed by upstream skin plate, downstream skin plate & horizontal members. Figure '3' (on sheet no.3) shows the subcomponents of trunnion girder, which comprises of: 1. A pair of box girders marked 7', which are embedded in RCC piers & 2. A pair of cantilever axles marked '8', which are welded to box girders. Figure '4' (on sheet no.4) shows the subcomponents of hoisting system, which comprises of: 1. Hoisting bracket marked '9', which is welded to gate leaf 2. Axle for hoisting bracket marked '10', for connecting it with hydraulic jack. 4 3. Hydraulic jack marked'11' 4. Bypass tube marked '12' & Check valve marked '13', which are provided for the hydraulic jack 5. Support bracket marked '14' for hydraulic jack 6. Axle connecting hydraulic jack & support bracket marked '15' & 7. Cantilever support box marked '16' for support brackets of hydraulic jack. The hydraulic jack is connected at its front end to the hoisting bracket '9' which is welded to gate leaf. The hydraulic jack is connected at its rear end to support brackets '14' & the support brackets are in turn supported by the cantilever support box '16'. The cantilever support box is welded to the inspection bridge (shown by dotted lines). Figure '5' (on sheet no.5) shows the sub components of sealing system. These comprise of: 1. Side seal seats marked '17', which are embedded in the RCC piers 2. Bottom seal seat marked '18', which is embedded in the crest of weir concrete. 3. Bottom rubber seal marked '19', which is bolted to the bottom horizontal member of the gate leaf & 4. Side rubber seals marked '20', which are bolted to the end girders of gate leaf. The side & bottom rubber seals are clamped to gate leaf by means of bolts. Having described construction, the PRINCIPLE OF OPERATION of gate is now described herein for different conditions:- Normally the check valve mounted on by-pass tube of hydraulic jack is kept open, so that the hydraulic hoist does not interfere in normal automatic operation of gate. In this automatic mode the gate shall operate as described below :- 5 Case 1:- There is no water on upstream side or river side as well as on downstream side or sea side. As shown in figure 1A, the gate is inclined & is provided with a hinge near its top end. Due to this arrangement, self weight of gate tends to provide closing moment and therefore the gate remains in closed position, when there is no water on either sides. Case 2:- Water level on downstream or sea side is above gate sill level. The downstream water load provides a closing moment on the gate. Under these circumstances, there are three possible hydraulic conditions. The operation of gate under these 3 conditions will be as under :- (i) When there is no water on upstream side, the gate will remain in closed position, as downstream water load as well as self weight of gate will provide closing moments. (ii) When water level on upstream side is above gate sill level, but is lower than downstream water level, the closing moment due to self weight and downstream water load will be greater than opening moment due to upstream water load and therefore gate will remain in closed position. (iii) When the upstream water level rises well above the downstream water level, the opening moment due to upstream water load will become greater than total closing moment due to self weight and downstream water load, and therefore the gate will open out. 6 Case 3:- Water level on upstream side is higher than gate sill level. The upstream water load provides an opening moment on the gate. Under these circumstances, there are three possible hydraulic conditions. The operation of gate under these 3 conditions will be as under: (i) When water on downstream side is below gate sill level - the gate may close or open depending on whether the opening moment due to upstream water load is smaller or greater than the closing moment due to self weight. The upstream water level at which the gate shall open out can be pre-decided at design stage, as per site requirements. (ii) When water on downstream side rises above gate sill level but is below the upstream water level - the gate may close or open depending on whether the opening moment due to upstream water load is smaller or greater than the combined closing moment due to self weight and downstream water load. The difference in upstream and downstream water levels at which the gate shall open out can be pre-decided at design stage, as per site requirements. (iii) When water on downstream side rises above the upstream water level, the gate shall remain in closed position, as the combined closing moment due to self weight and downstream water load shall exceed the opening moment due to upstream water load. A counter weight provided within the gate leaf ensures its adequate weight for developing required closing moment, so that the gate opens out at pre-decided levels to suit the hydraulic conditions at site as described above. Thus, in automatic mode the gate will exhibit specific operational behavior described above under different combinations of upstream and downstream water levels. 7 Under emergency or extra ordinary conditions, where the gate needs to be operated manually i.e. Opened or closed, irrespective of upstream and downstream water levels existing at site, the same can be done by use of hydraulic hoist. When the gate is to be operated manually, first the check valve of the bypass tube of hydraulic jack shall be closed. The hydraulic pump(not shown in drawings) shall be operated manually to actuate the hydraulic jack to enable opening or closing operation of gate. As long as the check valve of the by-pass tube remains in 'closed' position, the gate will remain 'locked' in the current position i.e. Closed, partially open or fully open. The gate can be returned to automatic mode by opening the check valve of by-pass tube. The novelty of the invention lies in the use of the water pressure as the actuating force to open or close the gate automatically, obviating the need for electricity for its operation. The differential water pressure caused by different water levels on upstream and downstream side automatically determines whether the gate should swing towards opening direction or closing direction. It also acts like a one way valve by preventing entry of sea water into the river as long as the water level in the river is below the sea water level. Another novelty of the invention lies in the use of a special design of the hydraulic hoist to enable its manual operation. The third novelty of the invention lies in the use of a by pass tube and a check valve in the hydraulic hoist which either allows automatic operation of the gate or enables locking of the gate in closed, partially open or fully open position. 8 Although the invention has been described with reference to a tidal regulator, which is a salinity ingress prevention structure, the application of invention is not limited to such structures. The invention shall also find use on other gated structures like barrages, weirs & dams constructed across rivers for storage, diversion or regulation of water. In such case, the terms upstream and downstream side shall correspond to up-the-river and down-the-river sides respectively. It shall also find use on canal structures like cross regulators and escapes. Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined. 9. I claim : 1. An automatic swing gate for use on tidal regulators, weirs, barrages, dams and canals, comprising of a gate leaf, a pair of trunnion girders embedded in supporting structure, a sealing system and a hydraulic hoisting system; wherein, the gate leaf is hung at its top end by a pair of hinges and swings about a horizontal axis, the direction of rotation and the angle of swing being determined by the water loads due to water on upstream and downstream sides of gate. 2. An automatic swing gate, as claimed in Claim no.1, wherein the rotating or swinging gate leaf comprises of an upstream skin plate, a downstream skin plate, horizontal stiffeners between the two skin plates, counterweights, a pair of end girders and a pair of trunnion hubs with bearings. 3. An automatic swing gate, as claimed in Claim no.1 & 2, wherein the gate leaf swing over a pair of cantilever axles welded to a pair of trunnion girders which are in turn embedded in supporting structure. 4. An automatic swing gate as claimed in Claim nos.1,2, & 3, which can be manually operated by means of single or a pair of hydraulic hoisting systems, wherein each hydraulic hoisting system comprises of a hydraulic cylinder or jack provided with a bypass tube, a check valve and a hydraulic hand pump with hoses, pipes and necessary fitments. 5. An automatic swing gate as claimed in claim nos.1, 2, 3, & 4 wherein the gate leaf is provided with a internal counterweight made of steel or concrete or other material filled inside the cavity formed by two skin plates & horizontal members or an external counterweight, welded anywhere on gate leaf, to suit the operating levels for automatic operation of the gate. 10 6. An automatic swing gate as claimed in claim nos.1, 2, 3, 4, & 5 wherein the structural components of gate leaf & trunnion girders are manufactured out of iron, steel, stainless steel, alloy steel, aluminum, bronze, fiber reinforced plastic or any other structural material. 7. A swing gate substantially as herein above described in the specification with reference to accompanying drawings. Dated this 23rdday of August 2007 11 ABSTRACT AN AUTOMATIC SWING GATE FOR USE ON TIDAL REGULATORS The fluctuation of sea water level between low tide and high tide causes ingress of saline water into the river near its junction with the sea. Whenever the high tide level is above the water level in the river, the sea water travels upto several kilometers inside the river and makes the adjacent land saline and unfit for crop cultivation. Tidal regulators are constructed near the junction of river & sea to overcome this problem. These regulators consist of a concrete or masonry weir, with electrically operated vertical lift or radial gates. The gates are normally kept in closed position, so that the sea water does not enter the river during high tide. When there is flood in the river, the gates are opened with electrically operated hoists to enable flood waters to pass out to the sea. Daily monitoring of river water and sea water levels needs to be done during monsoons to decide the timing and extent of gate operation. The present invention solves this problem by automatically excluding the possibility of sea water ingress, obviating the need for electricity for operation of gates, and also by eliminating the need for monitoring of sea and river water levels. The present invention comprises of a gate that swings about a horizontal axis with its hinges near the top end of the gate. The upstream or river side water exerts an opening moment on the gate while the sea water on downstream exerts a closing moment on the gate, simultaneously. Whenever the river water level is above the sea water level, the gate automatically opens and allows the river water to flow into the sea. Whenever the river water level is lower than the sea water level, the gate automatically closes and prevents entry of sea water into the river. The gate can also be manually closed or opened by means of a hydraulic hoist, to enable maintenance works like rubber seal changing and painting etc. The novelty of the invention lies in the use of the water pressure as the actuating force to open or close the gate automatically, obviating the need for electricity for its operation. The differential water pressure caused by different water levels in the river and sea, automatically determines whether the gate should swing towards opening direction or closing direction. It also acts like a one way valve by preventing entry of sea water into the river as long as the water level in the river is below the sea water level. Another novelty of the invention lies in the use of a special design of the hydraulic hoist to enable its manual operation. The third novelty of the invention lies in the use of a by pass tube and a check valve in the hydraulic hoist to allow automatic operation of the gate or to lock the gate in closed, partially open or fully open position.

Documents:

1622-MUM-2007-ABSTRACT(21-3-2012).pdf

1622-MUM-2007-ABSTRACT(23-9-2014).pdf

1622-mum-2007-abstract.doc

1622-mum-2007-abstract.pdf

1622-MUM-2007-ANNEXURE 2(23-9-2014).pdf

1622-MUM-2007-CANCELLED PAGES(21-3-2012).pdf

1622-MUM-2007-CLAIMS(AMENDED)-(21-3-2012).pdf

1622-MUM-2007-CLAIMS(AMENDED)-(23-9-2014).pdf

1622-MUM-2007-CLAIMS(AMENDED)-(7-10-2014).pdf

1622-MUM-2007-CLAIMS(MARKED COPY)-(7-10-2014).pdf

1622-mum-2007-claims.doc

1622-mum-2007-claims.pdf

1622-mum-2007-correspondence(2-5-2008).pdf

1622-MUM-2007-CORRESPONDENCE(21-4-2014).pdf

1622-mum-2007-correspondence(5-8-2008).pdf

1622-mum-2007-correspondence-received.pdf

1622-mum-2007-description (complete).pdf

1622-MUM-2007-DRAWING(21-3-2012).pdf

1622-MUM-2007-DRAWING(23-9-2014).pdf

1622-mum-2007-drawings.pdf

1622-MUM-2007-FORM 1(23-9-2014).pdf

1622-MUM-2007-FORM 13(23-9-2014).pdf

1622-mum-2007-form 18(5-5-2008).pdf

1622-MUM-2007-FORM 2(TITLE PAGE)-(21-3-2012).pdf

1622-MUM-2007-FORM 2(TITLE PAGE)-(23-9-2014).pdf

1622-mum-2007-form 2(title page)-(24-8-2007).pdf

1622-MUM-2007-FORM 3(23-9-2014).pdf

1622-mum-2007-form 9(5-5-2008).pdf

1622-mum-2007-form-1.pdf

1622-mum-2007-form-2.doc

1622-mum-2007-form-2.pdf

1622-mum-2007-form-3.pdf

1622-mum-2007-form-5.pdf

1622-MUM-2007-MARKED COPY(23-9-2014).pdf

1622-MUM-2007-REPLY TO EXAMINATION REPORT(21-3-2012).pdf

1622-MUM-2007-REPLY TO HEARING(23-9-2014).pdf

1622-MUM-2007-REPLY TO HEARING(7-10-2014).pdf

1622-MUM-2007-SPECIFICATION(AMENDED)-(21-3-2012).pdf

1622-MUM-2007-SPECIFICATION(AMENDED)-(23-9-2014).pdf