Patent · US Expired

Head control stand

US4621945A · kind A · utility

16Cited by
7References
3Claims
0Family size

Inventors

Key dates

Filing dateJan 11, 1985
Grant dateNov 11, 1986
Priority date
Expiry dateJan 11, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7494
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

In association with a subsurface drainage/irrigation tile system, a head control stand is provided to selectively control the flow of water through a drainage/irrigation tile system and in turn control the depth of the water table. An actuating unit which includes a water level sensor floating on the surface of the water table is disposed within a riser pipe which extends upward from a subsurface drainage tile. A valve disposed within the drainage tile is connected to the water level sensor and opens upon the sensor raising in response to a raising in the water table which allows water to flow through the valve and subsequently closes the valve upon lowering of the water table.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.