公开(公告)号：US5570030A

公开(公告)日：1996-10-29

申请号：US423555

申请日：1995-04-17

申请人： William E. Wightman

发明人： William E. Wightman

IPC分类号： G01N27/04 ,  G01R27/26

CPC分类号： G01N27/048 ,  G01N27/043 ,  Y10T137/1939

摘要： A sensor for measuring moisture changes in soil and having an electrically insulating cylindrical body along which bare electrical conductors are placed. A transmitter produces constant alternating current which is supplied to the sensor. The voltage which this current creates in the soil is detected by the electrical conductors on the sensor and is fed to a receiver. The receiver consists of electronic circuitry for determining the necessity for allowing irrigation to occur, and if so, switches on a solenoid controlling the water supply. When the sensor indicates sufficient irrigation has occurred, the electronic controls switch the irrigation off. A tube sensor comprising rigid metal tubes of equal length and secured by end members such that no two tubes touch is also provided, for example to measure moisture content changes of any granular material. A plurality of the tube sensors are connected in series with insulated electrically conducting cables to form a string of tube sensors, thereby providing a means to obtain an average moisture content of large surface areas or volumes of material.

摘要翻译： 用于测量土壤湿度变化的传感器，具有电绝缘圆柱体，裸电导体沿着该电绝缘圆柱体放置。 发射机产生恒定的交流电流，供给传感器。 该电流在土壤中产生的电压由传感器上的电导体检测，并被馈送到接收器。 接收器包括用于确定允许发生冲洗的必要性的电子电路，如果是，则开启控制供水的螺线管。 当传感器表示发生充分的灌溉时，电子控制器将关闭灌溉。 一种管传感器，其包括相等长度的刚性金属管并由端部构件固定，使得也不提供任何两根管接触，例如以测量任何颗粒材料的水分含量变化。 多个管传感器与绝缘导电电缆串联连接以形成一串管传感器，从而提供获得大表面积或体积材料的平均含水量的方法。