Atmosphere control system for growing mushrooms and the like

Claim 2

In a closed mushroom growing chamber including means for storing a plurality of mushroom growing trays under controlled environmental conditions, the improvement comprising a ventilation system including a. means for continuously withdrawing air from said chamber, b. means for measuring the concentration of carbon dioxide in said chamber and comparing said concentration to a preselected desired concentration, c. means for transmitting an output signal proportional to the amount by which said carbon dioxide concentration exceeds said pre-selected desired concentration, d. means responsive to said output signal for separating a portion of said air withdrawn from said chamber and exhausting said separated portion from the system and for adding to the air withdrawn from said chamber, after said portion has been separated, a quantity of fresh air, the quantity of said fresh air added and of the portion of withdrawn air separated being calculated to reduce said carbon dioxide concentration in said chamber to said pre-selected desired concentration, and e. means for continuously supplying to said chamber said withdrawn air remaining after said portion has been removed therefrom and said quantity of fresh air has been added thereto.

Claim 3

An improved mushroom growing chamber, as recited in claim 1, wherein said continuous withdrawal means includes (i) a first outlet duct with a first damper and automatically controlled damper operator, said first duct communicating with the ambient atmosphere and (ii) a second outlet duct with a second damper and automatically controlled damper operator, and said continuous introducing means includes an inlet duct with a third damper and automatically controlled damper operator, said inlet duct communicating with the ambient atmosphere, said second damper being proportionally closed and said first and third dampers being proportionally opened in response to said signal, said first and third damper and said second damper being normally closed and said second damper being normally opened when said signal indicates said carbon dioxide concentration not to exceed said pre-selected desired concentration, said outlet duct communicating with said inlet duct downstream of said second damper.

Claim 4

An improved mushroom growing chamber, as recited in claim 2, wherein said continuous air withdrawing means and said continuous air supplying means consist of fans communicating, respectively, with ventilation return ducts and ventilation supply ducts in said chamber, said fans being of sufficiently high capacity to replace the total volume of air in said chamber in a time interval of from 1 to 5 minutes.

Claim 5

An improved mushroom growing chamber, as recited in claim 3, wherein said air withdrawing means includes temperature sensing means and relative humidity sensing means and said air supplying means includes air heating, cooling, and humidifying means, said heating, cooling, and humidifying including automatic control means responsive to differences between the temperature and relative humidity indicated by said sensing means and pre-selected desired temperature and humidity levels.

Claim 6

An improved mushroom growing chamber, as recited in claim 4, wherein said heating means consists of a resistance heater located downstream of said ventilation air supply fan, said cooling means consists of a chilled water coil located just upstream of said ventilation air supply fan, and said humidifying means consists of steam inlets disposed downstream of said heating means.

Claim 7

An improved mushroom growing chamber, as recited in claim 5, wherein said pre-selected desired temperature and humidity levels are 62*F. and 95 percent relative humidity respectively.

Claim 8

An improved mushroom growing system including a plurality of improved mushroom growing chambers as recited in claim 4, wherein each such chamber is one of several elongated chambers, half of which are disposed on an upper level and half of which are disposed on a lower level of a common housing, each of said chambers providing means for storing said mushroom growing trays in stacks along the elongated side-walls of said chamber with an access aisle therebetween, said ventilation return ducts being disposed generally along said aisle and said ventilation supply ducts being disposed generally along both elongated side-walls of each said chamber.

Claim 9

An improved mushroom growing sYstem, as recited in claim 7, wherein said supply and return ducts are disposed along the ceiling of said upper chambers and along the floor of said lower chambers.

Claim 10

An improved mushroom growing system, as recited in claim 8, wherein said supply and return ducts include a plurality of inlet and outlet openings distributed along the length of said elongated chambers, said inlet and outlets of said supply and return ducts being horizontally directed.

Claim 11

An improved mushroom growing system, as recited in claim 9, wherein said outlet openings of said supply ducts are directed toward the respective side-walls of said chambers along which said supply ducts are disposed and a deflector is disposed between said outlet openings and the remainder of said chamber to direct air from said outlet opening into a sheet flow along said sidewall.

Claim 12

An improved mushroom growing system including a plurality of improved mushroom growing chambers as recited in claim 1, wherein fresh air is supplied to all of said ventilation systems from a controlled rate heat exchange unit and exhaust air from all of said ventilation systems is exhausted to said heated exchange unit, said unit consisting of: a. two adjacent compartments, one of said compartments having an inlet for receiving said exhaust air from said ventilation systems and an outlet to the ambient atmosphere and the second of said compartments having an inlet from the ambient atmosphere and an outlet communicating with the supply side of said ventilation systems, b. a heat transfer member having relatively large surface area and high heat capacity and heat transfer constants, and adapted to continuously move from one of said compartments to the other of said compartments and back, said member being adapted to transfer heat between the air in the respective compartments and thereby to tend to equilibrate the temperature of said air, and c. means to cause said heat transfer member to move between said chambers at a rate proportional to the difference between a pre-selected temperature and the temperature of fresh air received by said heat exchange unit.

Claim 13

An improved mushroom growing system, as recited in claim 11, wherein said heat transfer member comprises at least one metallic wheel with a plurality of spokes mounted and adapted to rotate with parts thereof in both of said compartments at all times.

Claim 14

An improved mushroom growing system, as recited in claim 12, further including a sensor for sensing the temperature of air in said second compartment, comparing it to a preselected desired temperature and producing an output signal proportional to the difference between said temperatures and means responsive to said signal for controlling the speed of rotation of said wheel in proportion to said temperature difference.

Claim 15

An improved mushroom growing system, as recited in claim 13, wherein heating means is provided in the inlet of said second compartment to raise the temperature of incoming ambient air which is below 32* to 32*F.

Claim 16

An improved mushroom growing system including a plurality of improved mushroom growing chambers, as recited in claim 4, where fresh air is supplied to all of said ventilation systems from a controlled rate heat exchange unit and exhaust air from all of said ventilation systems is exhausted to said heated exchange unit, said unit consisting of: a. two adjacent compartments, one of said compartments having an inlet for receiving said exhaust air from said ventilation systems and an outlet to the ambient atmosphere and the second of said compartments having an inlet from the ambient atmosphere and an outlet communicating with the supply side of said ventilation systems, b. a heat transfer member having relatively large surface area and high heat capacity and heat transfer constants, and adapted to continuously move from one of said compartments to the other of said compartments and back, said member being adapted to transfer heat between the aiR in the respective compartments and thereby to tend to equilibrate the temperature of said air, and c. means to cause said heat transfer member to move between said chambers at a rate proportional to the difference between a pre-selected temperature and the temperature of fresh air received by said heat exchange unit.

Claim 17

An improved mushroom growing system, as recited in claim 15, wherein said heat transfer member comprises at least one metallic wheel with a plurality of spokes mounted and adapted to rotate with parts thereof in both of said compartments at all times.

Claim 18

An improved mushroom growing system, as recited in claim 16, further including a sensor for sensing the temperature of air in said outlet of said second compartment, comparing it to a pre-selected desired temperature and producing an output signal proportional to the difference between said temperatures and means responsive to said signal for controlling the speed of rotation of said wheel in proportion to said temperature difference.

Claim 19

An improved mushroom growing system, as recited in claim 17, wherein heating means is provided in the inlet of said second compartment to raise the temperature of incoming ambient air which is below 32* to 32*F.

Claim 20

In a mushroom growing system including a closed temperature-controlled atmosphere environment and a ventilation system therefor wherein fresh air at ambient temperature is introduced into the system and an equivalent amount of air from the closed atmosphere environment is exhausted to the ambient atmosphere, the improvement consisting of a controlled rate heat exchanger to thermally treat the incoming fresh air so that its temperature approaches that of said exhaust air, said heat exchanger consisting of a. two adjacent compartments, one of said compartments having an inlet for receiving said exhaust air from said ventilation system and an outlet to the ambient atmosphere and the second of said compartments having an inlet from the ambient atmosphere and an outlet communicating with the supply side of said ventilation system, b. a heat transfer member having relatively large surface area and high heat capacity and heat transfer constants, and adapted to continuously move from one of said compartments to the other of said compartments and back, said member being adapted to transfer heat between the air in the respective compartments and thereby to tend to equilibrate the temperature of said air and c. means to cause said heat transfer member to move between said chambers at a rate proportional to the difference between a preselected temperature and the temperature of fresh air received by said heat exchange unit.

Claim 21

In a mushroom growing system including a closed temperature-controlled atmosphere environment and a ventilation system therefor wherein fresh air at ambient temperature is introduced into the system and an equivalent amount of air from the closed atmosphere environment is exhausted to the ambient atmosphere, the improvement consisting of a controlled rate heat exchanger to thermally treat the incoming fresh air so that its temperature approaches that of said exhaust air, said heat exchanger consisting of a. two adjacent compartments, one of said compartments having an inlet for receiving said exhaust air from said ventilation system and an outlet to the ambient atmosphere and the second of said compartments having an inlet from the ambient atmosphere and an outlet communicating with the supply side of said ventilation system, b. a heat transfer member having relatively large surface area and high heat capacity and heat transfer constants, and adapted to continuously move from one of said compartments to the other of said compartments and back, said member being adapted to transfer heat between the air in the respective compartments and thereby to tend to equilibrate the temperature of said air and c. means to cause said heat transfer member to move between said chambers at a rate proportional to the difference between a preselected temperature and the temperature of fresh air received by said heat exchange unit.

Claim 22

An improved mushroom growing system, as recited in claim 19, wherein said heat transfer member comprises at least one metallic wheel with a plurality of spokes mounted and adapted to rotate with parts thereof in both of said compartments at all times.

Claim 23

An improved mushroom growing system, as recited in claim 20, further including a sensor for sensing the temperature of air in said outlet of said second compartment, comparing it to a pre-selected desired temperature and producing an output signal proportional to the difference between said temperatures and means responsive to said signal for controlling the speed of rotation of said wheel in proportion to said temperature difference.

Claim 24

An improved mushroom growing system, as recited in claim 21, wherein heating means is provided in the inlet of said second compartment to raise the temperature of incoming ambient air which is below 32* to 32*F.