GB1349001A - Controlled environment apparatus and process for plant husbandry - Google Patents

Abstract

1349001 Air conditioning ENVIRONMENT ONE CORP 31 March 1971 8315/71 Heading F4V [Also in Division A1] An apparatus for growing plants in a controlled environment comprises a growing chamber 3 and a removable top section 8 which contains fluorescent lights 31 and incandescent lights, the latter serving to heat the growing chamber 3 and being controlled by a thermostat 80 therein. The lights are turned on and off by a timer 20. A fan 37 powered by an electric motor 39 draws outside air through pivotable louvres 36 at one end of the top section 8, and circulates it past the motor 39 and the lights to cool them; the air leaves through louvres 40. A fan 42 powered by the motor 39 circulates air through the growing chamber 3 when a vent valve 43 is open. Carbon dioxide is supplied to the growing chamber 3 from a control volume chamber 60; this is supplied from an exchangeable pressurized cylinder 52 via a pressure regulator 53, adjustable by means of a linkage from a control panel 16, and via a three-way valve 57. An expansible chamber actuator 44 is connected to the control volume chamber 60, so that while the latter is pressurized the actuator 44 acts to hold the vent valve 43 open against spring pressure. When the timer 20 actuates the lights it also actuates a solenoid 63 which rotates the three-way valve 57 to cut off the cylinder 52 and connect the control volume chamber 60 to the growing chamber 3 via line 62; the vent valve 43 then closes since the actuator 44 is also vented to the lower pressure in the growing chamber 3. The pressure regulator 53 is connected to a dial 17 on the control panel 16 which can be calibrated to indicate the carbon dioxide concentration in the growing chamber 3. The relative humidity is maintained at a high level in the presence of the carbon dioxide, the plants being held in soil in holed plant pots 1 supported on spaced slats above a reservoir of liquid nutrient. Manual override switches may be provided on the control panel. An automatic electric coupling 70 connects the top section 8 to the remainder of the apparatus when the top section 8 is placed in position.