Climatic control especially for animal buildings

Claim 2

In a control mechanism for controlling ventilation, a thermostatic switch having a winter mode and a summer mode, a sensing element having a variable resistor connected to the thermostatic switch in the winter mode, responding to an electrical quantity which dominates the control, a transistor switching mechanism energized and connected to the sensing resistor in the winter mode to respond to its change in resistance, a relay connected to the output side of the transistor switching mechanism, a series of ventilators, means for energizing the relay and when this occurs to operate the ventilators, a timer switch energized in the summer mode, operatively connected to a rain switch, means for opening the ventilators in the summer mode if the timer switch indicatEs night and the rain switch indicates fair weather, means for closing the ventilators in the summer mode if the timer switch indicates night and the rain switch indicates precipitation, and means for closing the ventilators in the summer mode if the timer switch indicates day.

Claim 3

In a mechanism of claim 1, having for the winter mode interposed electrically between the sensing resistor and the transistor switching mechanism, a time delay network for delaying the response of the transistor switching mechanism, the transistor switching mechanism including a PNP junction transistor and a NPN junction transistor, the input side of the switching mechanism being connected with the collector of the PNP junction transistor and the base of the PNP junction transistor being also connected to the input, the output side of the transistor switching mechanism being connected with the collector of the NPN junction transistor and the base of the PNP junction transistor being connected also to the output, the respective emitters of the transistors being connected to the high and low side of the power source.

Claim 4

A mechanism of claim 2, in which the time delay network includes a time delay capacitor and time delay resistors, a first time delay resistor being connected in series with the capacitor between the sensing resistor and the input of the switching transistors, and a second time delay resistor being connected in parallel with a condenser and in series with the first time delay resistor.

Claim 5

A mechanism of claim 3, in which the first and second time delay resistors are part of a potentiometer which includes means for increasing and reducing their resistance in unison.

Claim 6

A mechanism of claim 4, in which the time delay network also includes a third time delay resistor in parallel with the first time delay resistors and with the capacitor.

Claim 7

A mechanism of claim 5, in which the time delay network also includes a fourth time delay resistor and a fifth time delay resistor which are in series with the first time delay resistor and in parallel with the capacitor, and the second time delay resistor, the input of the switching transistors being connected between the fourth and fifth time delay resistors.

Claim 8

A mechanism of claim 6, in which the switching transistor mechanism includes a first PNP junction transistor, a second NPN junction transistor and a third PNP junction transistor, and first, second and third switching resistors, the first transistor being connected with its collector on the input side, its emitter connected through the first switching resistor to the high side of the power source and its base connected through the second switching resistor to the base of the third switching resistor, the second switching transistor having its base connected to the input, its emitter connected to the grounded side of the power source, and its collector connected to the second switching resistor and through it to the base of the third switching transistor, the third switching resistor being connected between the base of the third switching transistor and the high side of the power source, the emitter of the third switching resistor being connected to the high side of the power source, and the collector of the third switching transistor, being connected to one side of the relay.