Vapor pressure control system for drying and curing products
OwnerDavid Sandelmaninventor
Life of this patent
Estimating the term…
Abstract
A system to control the conditions of an aging room, also known as a conditioned space, for products in which independent feedback loops control the dry bulb temperature and the dew point while controlling the difference between the vapor pressure in the room and the vapor pressure of the products being dried, thereby controlling the amount of and rate of water or water vapor loss of the products and, therefore controlling its quality, the system also including target controls, a thermoelectric cooler and lighting controls.
Claims14
A system for controlling the drying of a product, said product having a specific vapor pressure, said product located within a conditioned space, said system comprising:
- a first sensor to determine a dry bulb temperature in said conditioned space;
- a second sensor to determine the dew point value in said conditioned space;
- a controller responsive to the dew point value in said conditioned space with respect to the vapor pressure of the product to control the aging of said product by removing water vapor from said conditioned space,
- wherein said controller comprises two independent PID control loops, one of said two PID control loops is connected to receive the dry bulb temperature from the first sensor and a set point value for the dry bulb temperature to control the dry bulb temperature in said conditioned space and the other of said two PID control loops is connected to receive the dew point value from the second sensor and a set point value for the dew point to control said dew point value of said conditioned space;
- cooling coils, said controller responsive to the dew point value in said conditioned space controlling the temperature of said cooling coils;
- a fan, said controller also responsive to the dry bulb temperature to control the air flow through said cooling coils with said fan;
- a compensator which communicates an error signal in said dry bulb control loop to bias the dew point control loop;
- and
- a user interface that is configured to receive as input from a user, and to set, based on the input from the user, for the conditioned space, a schedule of target vapor pressures, target dry bulb temperatures, and target air flow values;
- wherein the one PID control loop uses the dry bulb temperature from the first sensor and the set point value for the dry bulb temperature to calculate an error value that is used to control the flow of air through said cooling coils,
- wherein the other PID control loop uses the dew point value and the set point value for the dew point value to calculate an error value that is used to control a temperature of said cooling coils,
- wherein said controller controls an amount of water removed, and a rate of water removal from said product by controlling the addition or extraction of moisture or heat to or from the conditioned space over the period of time by automatically adjusting the set point for the dew point and the set point for the dry bulb temperature to adjust the vapor pressure, the dry bulb temperature and the air flow based on the schedule of target vapor pressures, target dry bulb temperatures, and target air flow values.
Dependencies are inferred from the claim text.