GB2233045A

GB2233045A - Hydraulic control system

Info

Publication number: GB2233045A
Application number: GB9002465A
Authority: GB
Inventors: William Kingston
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-02-07
Filing date: 1990-02-05
Publication date: 1991-01-02
Also published as: GB9002465D0

Abstract

Energy is extracted from a water stream by cyclicly letting water into and out of a container 1 so that the oscillating water level in the container drives an air turbine. A weighted float 9, 10 within the container operates the container's valves 5, 6 through cables 27, (31), Fig 5, at prescribed upper and lower internal water levels. External floats (18), (19) Figs 2 and 3 similarly control the internal levels at which the weighted float acts, in accordance with the level of water in the stream. The valves 5, 6 are counterweighted, Fig 1, for ease of operation. <IMAGE>

Description

HYDRC-POWER CONTROL SYSTEM TECHNICAL FIELD The invention relates to low-head hydro energy devices.

BACKGROUND INFORMATION The invention provides a control means for the already knawn type of device in which water from a stream is allowed to enter and leave a container cyclically so that its oscillating level within the container drives an air turbine.

This invention discloses means for controiling water entry and exit in such a system.

DISCLOSURE OF THE INVENTION In this invention, water entrv and exit is b upstream and downstream apertures which can be closed by vertically sliding gates counterbalanced to minimise the amount of power required to open or close them. An internal float/weight combination is connected by cables in such a way as to open and close each of them cyclically. when the internal water level rencheC prescribed upper and lower limits. Upstream and downstream floats similarly control these limits in accordance with the level of water in the stream.

BRIEF DESCRIPTION OF THE DRAWIN Fig. 1 is a sectional view. showing the arrangement of the upstream and downstream sates and the cable and pullev arrangements linking them so that they counterweiht each other for ease of operation.

Fig. 2 is a sectional view. showing the float, cable and pulley arrangement to compensate for different upstream water levels.

Fig. 3 is a sectional view , showing the float, cable and pulley arrangement to compensate for different downstream water levels.

Fi. 4 is a sectional view, showing the float and cable arrangement at a point in the operating cycle just before the opening of the downstream gate.

Fi. 5 is a sectional view showing: the float and cable arrangement at a point in the operating cycle just before the opening of the upstream gat.

DESCRIPTION OF THE PREFERRED EMBODIMENT In Fig. 1, 1 is the water container, set in the water stream, and 2 is the outlet for air to a turbine. 3 is an upstream aperture and 4 a downstream aperture in the walls of container 1, each adapted to be closed by vertical movement in slides (not shown) of corresponding gates 5, 6 Gates 5,6 are lied by cable 7, which passes over pulleys 4 so that each gate ats as a counterweight to the other so reducn ~ the amount of force required to open and close them.

In Fig 2, 9 is a float inside container 1, which is capable of lifting attached weight 10, tn which is attached lower pulley array 11, the function of which will be described below. Cable iJ leads from pulley array 11. around pulley t3 to oe end of tension spring 14. the other end of which is fixed to the wall of container 1 Cable 15 is also attached to the same end of spring 14 as cable 12, and leads through opening 16 in the wall of container 1, around pulley 17, to external upstream float 18. It will be evident that if float 18 rises because there is more water in the stream, it will extend spring 14, thus allowing the anchoring point of pulley array 11 to rise an equal distance.In the same way, if float 18 falls, spring 14 will be allowed to contract, lowering the anchoring point of pulley array 11 correspondingly.

In Fig. 3, 19 is an external downstream float, from which cable 20 leads around pulley 21, through opening 22 in the wall of container 1, around pulleys 23, 4.

and 25 to upper pulley array 26. As in the case of external upstream float la. the connection through cable will act so as to move the anchoring point of upper pulley array 26 in line with the downstream water level.

In Fig. 4, cable 27 is attached to float 9 and weight 10 and runs through pulley array 11 and over pulleys 25.

29, to gate 6.

In Fig. 5. cable 31 is attached to float 9 and weight 10. and runs through pulley array 26 and over pulleys 32.

and 32, to gate 5.

Operation of the preferred embodiment will now be described, with particular reference to Figs. 4 and 5.

In Fi. ,. with downstream gate 6 closed. water flows in through the open upstream aperture . and float 9 rises.

Until cable 12 (see Fig. 2) reaches its maximum extension, no force is exercised on either gate by float 9. However, as the water approaches the upstream external level. cable 12 anchors the lower end of pulley array 11. Further rise of float 9 then raises the upper end of pulley array 11. which is only possible if there is a considerable shortening of the length of cable 27 that is external t pulley array 11. This shortening of cable 27 lifts gate 6 open. Upstream gate 5 then falls under its own weight and closes.

In Fig, 5, with upstream gate 5 closed water leaves container 1 through open downstream aperture 4, and the water level inside container 1 drops, taking float 9 with it. As the water level approaches that downstream of the container. cable 2 (seeFig. 3) prevents the upper end of pulley array 26 from moving any further downwards. Weight 10 then acts through pulley array 26.

to shorten the length of cable 1 that is external to pulley array 26, This lifts open upstream gate 5, which in turn allows downstream gate 6 to fall under its own weight and close.

The function of upper and lower pulley arrays 11 and 26 is to provide delayed action to the way in which internal float 9 and weight 10 cause movement of upstream and downstream gates 5 and 6. The usual function of such an array is such that a large movement of the cable which passes through it. brings about a small change in the distance between the end of the array, so as to multiply the force which can be applied to some object. In the present case, the operation is reversed: a small change in the distance between the ends of the array is used to bring about a large movement in the cable which passes through it. By this means, only the last few inches of movement of float 9 and weight 10 at the end of a cycle, as a result of the rise or fall of the water within container 1. will be transmitted to the gates through cables 27 and 31, but then the gates will be forced to move rapidly. Without the pulley arrays, the gates would be in constant movement at the same relative speed as the filling or emptying of container 1, and the operation would therefore be less efficient.

Claims

1 In a hydraulic energy system of the type wherein water cvclicallv floods into and empties from a container in a stream through upstream and downstream apertures fitted with alternately operating closure means. control means for said closure means comprising.

in combination. weighted flotation means within said container, connecting means between said flotation means and said aperture closure means, said connecting means being adapted t close said upstream aperture and open said downstream aperture when said flotation means is at a first prescribed level. and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level. said second level being lower than said first level.

2. In a hydraulic energy system of the type wherein water cyclically floods into and empties from 9 container in a stream through upstream and downstream apertures fitted with alternately operating closure means, control means for said closure means comprising.

in combination, weighted flotation means within said container, connect means between said flotation means and said aperture closure means. said ~connecting means being adapted to close said upstream aperture and open said downstream aperture when said flotation means is at first prescribed level, and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level said second level being lower than said first level and connecting means between said closure means said connecting means being adapted to enable one closure means to act as a counterweight to the other.

3. In a hydraulic energy system of the type wherein water cyclically floods into and empties from å container in a stream through upstream and downstream apertures fitted with alternately operating closure means. control means for said closure means comprising, lr, combination, weighted flotation means within said container. connection means between said flotation means and said aperture closure means said connecting means bring adapted to close said upstream aperture and open said downstream aperture when said flotation means is at a first prescribed level and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level. said second level being lower than said first level. and means for varying said first level in accordance with the upstream level. and said second level in accordance with the downstream level, of said stream.

4. Control means as in Claim 1, additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said gates.

5. Control means as in Claim 2 additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said gates.

6. Control means as in Claim 3. additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said sates.

Control means as in Claim 2. additionally incorporating means for varying said first level in accordance with the upstream level. and said second level in accordance with the downstream level, of said stream.

Amendments to the claims have been filed as follows 1. A hydraulic energy system of the type wherein water cyclically floods into and empties from a container in a stream through upstream and downstream apertures fitted with alternately operating closure means, wherein the improvement consists in means for varying the volume of water permitted to pass through said closure means on each cycle of operation in accordance with variations in the water level of said stream.

2. In a hydraulic energy system of the type wherein water cyclically floods into and empties from a container in a stream through upstream and downstream apertures fitted with alternately operating closure means, control means for said closure means comprising, in combination, weighted flotation means within said container, connecting means between said flotation means and said aperture closure means, said connecting means being adapted to close said upstream aperture and open said downstream aperture when said flotation means is at a first prescribed level, and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level, said second level being lower than said first level.

2. In a hydraulic energy system of the type wherein water cyclically floods into and empties from a container in a stream through upstream and downstream apertures fitted with alternately operating closure means, control means for said closure means comprising, in combination, weighted flotation means within said container, connecting means between said flotation means and said aperture closure means, said connecting means being adapted to close said upstream aperture and open said downstream aperture when said flotation means is at a first prescribed level, and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level, said second level being lower than said first level and connecting means between said closure means, said connecting means being adapted to enable one closure means to act as a counterweight to the other.

4. In a hydraulic energy system of the type wherein water cyclically floods into and empties from a container in a stream through upstream and downstream apertures fitted with alternately operating closure means, control means for said closure means comprising, in combination, weighted flotation means within said container, connecting means between said flotation means and said aperture closure means, said connecting means being adapted to close said upstream aperture and open said downstream aperture when said flotation means is at a first prescribed level, and to open said upstream aperture and close said downstream aperture when said flotation means is at a second prescribed level, said second level being lower than said first level, and means for varying said first level in accordance with the upstream level and said second level in accordance with the downstream level, of said stream.

5. Control means as in Claim 2, additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said aperture closing means.

Control means as in Claim 3, additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said aperture closing means.

7. Control means as in Claim 4, additionally incorporating means whereby only the final section of the movement of said flotation means between said prescribed levels acts to move either of said aperture closing means.

8. Control means as in Claim 3, additionally incorporating means for varying said first level in accordance with the upstream level, and said second level in accordance with the downstream level, of said stream.

9. Control means for a hydraulic energy system substantially as hereinbefore described with reference to the accompanying drawings.