초록 ▼

An apparatus for automatically controlling a watering system in response to a comparison of an ambient condition with a time-varying reference level having an adjustable maximum value is disclosed. The invention includes an electrical circuit for monitoring and sensing the magnitude of the ambient c

An apparatus for automatically controlling a watering system in response to a comparison of an ambient condition with a time-varying reference level having an adjustable maximum value is disclosed. The invention includes an electrical circuit for monitoring and sensing the magnitude of the ambient condition and for converting the sensed magnitude into a proportional electrical signal. The invention further includes a first timer circuit for generating a triggering signal when the time-varying reference level exceeds the magnitude of the proportional electrical signal. This triggering signal is applied to a second timer circuit which actuates the watering system for a predetermined period of time in response to the triggering signal. Furthermore, the present invention includes a disabling circuit which compares the proportional electrical signal with a predetermined cut-off level and prevents the first timer circuit from generating the triggering signal whenever the magnitude of the proportional electrical signal passes the cut-off level. The present invention further includes a plurality of controls by which the time periods of the first timer and second timer circuits may be adjusted. Also, there are controls whereby predetermined reference levels can be established so that the apparatus is in a lock-out condition whenever the reference levels are passed.

대표청구항 ▼

An apparatus for automatically controlling a watering system in response to a comparison of an ambient condition with a time-varying reference level having an adjustable maximum value, said apparatus comprising: monitor means for sensing the magnitude of the ambient condition and converting the sens

An apparatus for automatically controlling a watering system in response to a comparison of an ambient condition with a time-varying reference level having an adjustable maximum value, said apparatus comprising: monitor means for sensing the magnitude of the ambient condition and converting the sensed magnitude into a proportional electrical signal; first timer means for generating a triggering signal when the time-varying reference level exceeds the magnitude of the proportional electrical signal; second timer means, responsive to the triggering signal, for actuating the watering system for a predetermined period of time; and disabling means for comparing the proportional electrical signal with a predetermined cut-off level, and for preventing said first timer means from generating the triggering signal when the magnitude of the proportional electrical signal passes the cut-off level.