Control gates and valves

Abstract

The invention discloses an overshot control gate for use with trapezoidal irrigation channels. A gate has a rigid rectangular section adapted to, in use, be pivotally mounted to a base of a trapezoidal irrigation channel. A pair of triangular sections are pivotally mounted on opposite sides of the rigid rectangular section. Each of the triangular sections are divided into first and second triangular sections with a common apex at the base of the trapezoidal irrigation channel. Each of the first triangular sections are rigid and adapted to, in use, be pivotally mounted to opposite side walls of the trapezoidal irrigation channel. Each of the second triangular sections including the pivotal mounting on opposite sides of the rigid rectangular section are formed of a flexible material. Also disclosed is a pipe flow meter and a duckbill valve.

1 . A flexible pipe valve for controlling low pressure hydraulic networks, said valve including a flexible pipe member adapted to, in use, be connected to an entry or exit end of a pipe through which liquid is to flow, said valve having a lifting ring at its end opposite the connection to the entry or exit end of said pipe, said lifting ring being coupled to an actuator for raising and lowering said flexible pipe member above a surface level or static head of said liquid. 
     
     
         2 . The flexible pipe valve of  claim 1 , further including a coupling ring adapted to be coupled to said entry or exit end of said pipe and a plurality of struts pivotally attached between said lifting ring and said coupling ring to provide support for said flexible pipe member whilst being raised and lowered. 
     
     
         3 . The flexible pipe valve of  claim 2 , wherein said flexible pipe member includes a plurality of annular rings along its length to provide support for said flexible pipe member whilst being raised and lowered. 
     
     
         4 . The flexible pipe valve of  claim 2 , wherein said lifting ring has a U- or C-shaped member pivotally attached to said lifting ring and said actuator is pivotally attached to said U- or C-shaped member. 
     
     
         5 . The flexible pipe valve of  claim 2 , wherein said lifting ring is cylindrically shaped. 
     
     
         6 . The flexible pipe valve of  claim 1 , further including:
 a coupling ring adapted to be coupled to said entry or exit end of said pipe; and   a plurality of struts pivotally attached between said lifting ring and members on said coupling ring providing a vertical offset for the pivot attachment to provide support for said flexible pipe member whilst being raised and lowered.   
     
     
         7 . A valve system for controlling liquid flow in a hydraulic network, said valve system comprising:
 a flexible pipe member having a proximal end and a distal end, the proximal end being adapted to, in use, be coupled to a pipe through which liquid flows;   a lifting ring coupled to the distal end of said flexible pipe member;   an actuator coupled to the lifting ring; and   a motor coupled to a rigid point and to the actuator, the motor adapted to, in use, control a length of the actuator between the motor and the lifting ring, the controlled length of the actuator between the motor and the lifting ring causing the flexible pipe member to raise or lower to a height relative to a surface level or static head of said liquid and thereby controlling the liquid flow.   
     
     
         8 . The valve system of  claim 7 , further including:
 a coupling ring adapted to be coupled to the proximal end of said flexible pipe member; and   a plurality of struts pivotally attached between said lifting ring and said coupling ring to provide support for said flexible pipe member whilst being raised and lowered.   
     
     
         9 . The valve system of  claim 8 , wherein said flexible pipe member includes a plurality of annular rings along its length to provide support for said flexible pipe member whilst being raised and lowered. 
     
     
         10 . The valve system of  claim 8 , wherein said lifting ring has a U- or C-shaped member pivotally attached to said lifting ring and said actuator is pivotally attached to said U- or C-shaped member. 
     
     
         11 . The valve system of  claim 8 , wherein said lifting ring is cylindrically shaped. 
     
     
         12 . The valve system of  claim 7 , further including:
 a coupling ring adapted to be coupled to said proximal end of said flexible pipe member; and   a plurality of struts pivotally attached between said lifting ring and members on said coupling ring for providing a vertical offset and providing support for said flexible pipe member whilst being raised and lowered.   
     
     
         13 . A method of controlling liquid flow in a hydraulic network, said method comprising:
 allowing liquid to flow through a pipe and a flexible pipe member, the flexible pipe member having a proximal end and a distal end, the pipe coupled to the proximal end of the flexible pipe member, a lifting ring coupled to the distal end of the flexible pipe member, an actuator coupled to the lifting ring, and a motor coupled to a rigid point and to the actuator; and   controlling the motor to adjust a length of the actuator between the motor and the lifting ring, the controlled length of the actuator between the motor and the lifting ring causing the flexible pipe member to raise or lower to a height relative to a surface level or static head of the liquid and thereby controlling the liquid flow.