Regulating temp. and ventilation in animal breeding house - using resistance probe above animals and electronic circuit to control motor operated ventilator flaps

摘要

The temp. and ventilation of a farm bldg. such as a breeding house are controlled to maintain a constant temp. The controller operates a ventilation fan as well as a heat generator. The temp. is measured by a resistance probe (2) mounted directly above the animals. The probe is connected to an amplifier which detects voltage changes which are passed to operational amplifiers acting as pulse generators when a triangular waveform is applied to their other inputs from a sawtooth generator. The pulse generators drive transistors which operate relays with contacts in motor (5, 6, 7) circuits. These motors open or close ventilator flaps while a third relay circuit operates a heating circuit when the temp. falls below a threshold level.