Humidity control system

• US 5,400,608 A
• Filed: 02/05/1993
• Issued: 03/28/1995
• Est. Priority Date: 02/05/1993
• Status: Expired due to Fees

• Current Assignee: Sensitech Incorporated (Carrier Global Corporation)
• Original Assignee: Ryan Instruments LP (Carrier Global Corporation)
• Inventors: Steed, Robert L., Ferris, Frank R. Jr.
• Primary Examiner(s): Tanner, Harry B.
• Application Number:
  US08/014,448
• Time in Patent Office: 781 Days
• Field of Search: 62/176.4, 62/171, 62/91, 62/288, 62/289, 62/291, 236/44 A, 236/44 R, 236/44 B, 236/44 C
• US Class Current: 62/91
• CPC Class Codes: B60H 1/3232 particularly adapted for load transporting vehicles B60H1/3226 takes precedence
• CPC Class Codes: B60H 1/32331 comprising means for the use of condensed liquid, e.g. for humidification or for improving condenser performance
• CPC Class Codes: B60H 3/022 for only humidifying the air
• CPC Class Codes: F25D 17/042 Air treating means within refrigerated spaces air conditioning in general F24F
• CPC Class Codes: F25D 2317/04131 Control means therefor

Abstract

A humidity control system is provided for controlling the humidity of the air confined within a container. The humidity control system includes sensors for determining the temperature of the air both within and outside the container. The sensors are also constructed to determine the humidity of the air inside the container. A controlled droplet applicator that is responsive to a humidity control signal is provided for increasing the humidity of the air within the container. A data processor is responsive to the sensors for providing the humidity control signal to increase and decrease the humidity of the air within the container. The humidity control system also includes a water flow control system for controlling the flow of water within the container. The water flow control system is responsive to the data processor for substantially preventing water from freezing in the controlled droplet applicator. In a preferred embodiment of the invention, the water flow control system further includes a drain pan for recycling water provided to the air by the controlled droplet applicator.

Claims

1. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially confines a quantity of air and wherein outside air is outside of the confined space, the confined space further including refrigerating coils for cooling the quantity of air in the confined space, said humidity control system comprising:

a first temperature sensor for determining the temperature of the quantity of air in the confined space, said first temperature sensor being constructed to provide a first temperature signal indicative of the temperature of the quantity of air in the confined space;

a second temperature sensor for determining the temperature of the outside air, said second temperature sensor being constructed to provide a second temperature signal indicative of the temperature of the outside air;

a humidity sensor for determining the humidity of the quantity of air in the confined space, said humidity sensor being constructed to provide a humidity sample signal indicative of the humidity of the quantity of air in the confined space;

a reservoir, positioned proximate the outside air, for containing water used to increase the humidity of the quantity of air in the confined space, said reservoir being constructed to contain no more than five gallons of water, said reservoir being further constructed with substantially flexible side portions to permit said reservoir to expand when the water contained therein freezes thereby to prevent damage to said reservoir;

a heater thermally coupled to said reservoir for providing heat to the water contained in said reservoir, said heater being responsive to a heat control signal for providing heat to the water contained in said reservoir;

a third temperature sensor for determining the temperature of the water contained in said reservoir, said third temperature sensor being constructed to provide a third temperature signal indicative of the temperature of the water contained in said reservoir;

a humidity system controller responsive to said humidity sample signal and said first, second, and third temperature signals for controlling the operation of the humidity control system, said humidity system controller being constructed to respond to said second and third temperature signals to provide said heat control signal to control the operation of said heater, said humidity system controller being further constructed to control the operation of said heater so that, when the temperature of the outside air proximate said reservoir is intermediate first and second predetermined temperatures, wherein said first predetermined temperature is greater than said second predetermined temperature, said heater is controlled to provide heat to the water contained in said reservoir, said humidity system controller being responsive to said third temperature signal to modulate said heat control signal to prevent the water contained in said reservoir from freezing;

a peristaltic pump coupled to said reservoir, said peristaltic pump being responsive to a pump control signal for pumping water to and from said reservoir, said humidity system controller being constructed to provide said pump control signal to control the operation of said peristaltic pump, said humidity system controller being constructed to control the operation of said peristaltic pump so that when said second temperature signal indicates that the temperature of the outside air proximate said reservoir is below said second predetermined temperature, water is pumped into said reservoir and when said second temperature signal indicates that the temperature of the outside air proximate said reservoir is above said second predetermined temperature water is pumped out of said reservoir;

a controlled droplet applicator coupled to said peristaltic pump for fluid flow therebetween, said controlled droplet applicator being responsive to a humidity control signal for converting water received from said peristaltic pump into water droplets sized small enough to be absorbed into the quantity of air of the confined space, said humidity system controller being constructed to provide said humidity control signal for controlling the operation of said controlled droplet applicator, said humidity system controller being responsive to said first temperature signal and said humidity system for determining the amount of water to be added to the air confined within the container and for providing said pump control signal and said humidity control signal in a manner to proportionally decrease the amount of water droplets provided to the quantity of air by said controlled droplet applicator thereby to control the humidity of the quantity of air contained in the confined space; and

a drain pan positioned below the refrigerating coils for collecting water released therefrom, said drain pan being coupled to said reservoir for providing the collected water to said reservoir.

2. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas said humidity control system comprising:

first sensor means for sensing the temperature and the humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means for increasing the humidity of the quantity of gas contained in the confined space;

water supply means coupled to said controlled droplet applicator means for supplying the water used to increase the humidity of the quantity of gas contained in the confined space, said water supply means being responsive to a water supply control signal to supply water to said controlled droplet applicator means and to withdraw water from said controlled droplet application means;

second sensor means for sensing the temperature of a gas proximate said water supply means; and

data processing means responsive to said first sensor means for controlling the operation of said controlled droplet applicator means and said water supply means to maintain the humidity of the gas contained in the confined space within a predetermined range, said data processing means being further responsive to said second sensor means for providing said water supply control signal so that when the temperature of the gas proximate said water supply means is below a first predetermined temperature, said water supply means withdraws water from said controlled droplet applicator means.

3. The humidity control system as recited in claim 2 wherein said water supply means further comprises:

reservoir means for containing the water supplied to and withdrawn from said controlled droplet applicator means; and

heater means responsive to said data processing means for providing heat to the water contained in said reservoir means.

4. The humidity control system as recited in claim 2 wherein said water supply means further comprises:

reservoir means for containing the water supplied to and withdrawn from said controlled droplet applicator means said second sensor means being constructed for sensing the temperature of a gas proximate said reservoir means; and

heater means responsive to said data processing means for providing heat to the water contained in said reservoir means, said data processing means being responsive to said second sensor means to control said heater means to supply heat to the water contained in said reservoir means when the temperature of the gas proximate said reservoir means is below a second predetermined temperature, said second predetermined temperature being greater than said first predetermined temperature.

5. The humidity control system as recited in claim 2 wherein said water supply means further comprises:

reservoir means for containing the water supplied to and withdrawn from said controlled droplet applicator means;

third sensor means for providing a signal to said data processing means indicative of the temperature of the water contained in said reservoir means; and

heater means responsive to said data processing means for providing heat to the water contained in said reservoir means, said data processing means being responsive to said third sensor means to control said heater means to supply heat to the water contained in said reservoir means to prevent the water contained in said reservoir means from freezing.

6. The humidity control system as recited in claim 3 wherein said reservoir is constructed with substantially flexible side portions.

7. The humidity control system as recited in claim 2 wherein said water supply means further comprises peristaltic pump means coupled to said reservoir means for pumping water and the quantity of gas contained in the confined space from said reservoir means to said controlled droplet applicator means and for pumping water from said controlled droplet applicator means to said reservoir means.

8. The humidity control system as recited in claim 2 wherein the confined space further includes refrigerating coils for refrigerating the quantity of gas contained in the confined space, wherein water condenses on the refrigerating coils and is periodically released therefrom, said humidity control system further comprising:

water collection means for collecting water released from the refrigerating coils, said water collection means being coupled to said water supply means for supplying the collected water thereto to recycle the condensed water.

9. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas, said humidity control system comprising:

first sensor means for sensing the temperature and the humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means for increasing the humidity of the quantity of gas contained in the confined space;

reservoir means for containing water supplied to said controlled droplet applicator means, said reservoir means including heater means responsive to a heat control signal for providing heat to the water contained in said reservoir means;

second sensor means for sensing the temperature of a gas proximate said reservoir means;

data processing means responsive to said first sensor means for controlling the operation of said controlled droplet applicator means and said water supply means to maintain the humidity of the gas contained in the confined space within a predetermined range, said data processing means being further responsive said second sensor means to control said heater means to supply heat to the water contained in said reservoir means when the temperature of the gas proximate said reservoir means is below a first predetermined temperature; and

pump means responsive to a pump control signal for pumping water to and from said reservoir means, said data processing means being further constructed to provide said pump control signal for controlling the operation of said pump means, said data processing means being further responsive to said second sensor means for providing said pump control signal so that water is pumped from said controlled droplet applicator means to said reservoir means when the temperature of the gas proximate said reservoir means is below a second predetermined temperature.

10. The humidity control system as recited in claim 9 wherein aid pump means further comprises peristaltic pump means coupled to said reservoir means for pumping water said reservoir means to said controlled droplet applicator means and for pumping water from said controlled droplet applicator means to said reservoir means.

11. The humidity control system as recited in claim 9 wherein said reservoir means is constructed with substantially flexible side portions.

12. The humidity control system as recited in claim 9 wherein the confined space further includes refrigerating coils for refrigerating the quantity of gas contained in the confined space, wherein water condenses on the refrigerating coils and is periodically released therefrom, said humidity control system further comprising:

water collection means for collecting water released from the refrigerating coils, said water collection means being coupled to said reservoir means for supplying the collected water thereto to recycle the condensed water.

13. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas, the confined space further including refrigerating coils for refrigerating the quantity of gas contained in the confined space wherein water condenses on the refrigerating coils and is periodically released therefrom, said humidity control system further comprising:

first sensor means for sensing the temperature and the humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means for increasing the humidity of the quantity of gas contained in the confined space;

reservoir means for containing water supplied to said controlled droplet applicator means, said reservoir means including water collection means for collecting water released from the refrigerating coils, said water collection means being coupled to said water supply means for supplying the collected water thereto to recycle the collected water;

second sensor means for sensing the temperature of a gas proximate said reservoir means;

data processing means responsive to said first sensor means for controlling the operating of said controlled droplet applicator means and said water supply means to maintain the humidity of the gas contained in the confined space within a predetermined range, said data processing means being further responsive to said second sensor means to control said heater means to supply heat to the water contained in said reservoir means when the temperature of the gas proximate said reservoir means is intermediate first and second predetermined temperatures, said first predetermined temperature being greater said second predetermined temperature; and

pump means responsive to a pump control signal for pumping water to and from said reservoir means, said data processing means being further constructed to provide said pump control signal for controlling the operation of said pump means, said data processing means being responsive to said second sensor means for providing said pump control signal so that water is pumped from said controlled droplet applicator means to said reservoir means when the temperature of the gas proximate said reservoir means is below a second predetermined temperature.

14. The humidity control system as recited in claim 13 wherein said pump means further comprises peristaltic pump means coupled to said reservoir means for pumping water from said reservoir means to said controlled droplet applicator means and for pumping water from said controlled droplet applicator means to said reservoir means.

15. The humidity control system as recited in claim 13 wherein said reservoir means is constructed with substantially flexible side portions.

16. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas, said humidity control system further comprising:

first sensor means for sensing the temperature and the humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means, responsive to a humidity control signal, for increasing the humidity of the quantity of gas contained in the confined space;

water supply means, responsive to a water supply signal, for supplying water to said control droplet applicator means, said water supply means including heater means for heating a portion of the water contained in said water supply means;

second sensor means for sensing the temperature of a gas proximate said water supply means;

data processing means for controlling the operation of said control droplet applicator means to maintain the humidity of the gas contained in the confined space above a predetermined value, said data means being responsive to said first sensor means for determining the amount of water that must be added to the gas contained in the container to increase the humidity above the predetermined value and for providing the humidity control signal to proportionally regulate the amount of water added to the gas contained in the container, said data processing means being further constructed to modulate said water supply signal in combination with said humidity control signal to proportionally regulate the amount of water added to the gas contained in the container, said heater means being responsive to said data processing means for heating a portion of water contained in said water supply means, said data processing means being responsive to said second sensor means to control said heater means to supply heat to the water contained in said water supply means when the temperature of the gas proximate said water supply means is below a first predetermined temperature; and

pump means responsive to a pump control signal for pumping water to and from said water supply means, said data processing means being further constructed to provide said pump control signal for controlling the operation of said pump means, said data processing means being responsive to said second sensor means for providing said pump control signal so that water is pumped from said controlled droplet applicator means to said water supply means means when the temperature of the gas proximate said water supply means is below a second predetermined temperature.

17. The humidity control system as recited in claim 16 wherein said pump means further comprises peristaltic pump means coupled to said reservoir means for pumping water from said reservoir means to said controlled droplet applicator means and for pumping water from said controlled droplet applicator means to said reservoir means.

18. A method for humidifying a confined space wherein the confined space contains a quantity of a gas and wherein the humidity of the gas is to be maintained at a predetermined value, the confined space including a reservoir for storing water, the reservoir being surrounded by outside air, the confined space also including refrigerating coils for cooling the quantity of the gas, said method comprising the steps of:

sensing the temperature and the humidity of the quantity of the gas in the confined space;

determining the difference between the sensed humidity and the predetermined value of humidity;

providing water droplets to the gas to proportionally decrease the difference between the sensed humidity and the predetermined value of humidity;

sensing the temperature of the outside air surrounding the reservoir and the temperature of the water stored in the reservoir;

heating the reservoir when the temperature of the outside air is within a predetermined range and the temperature of the water stored in the reservoir is below a predetermined value; and

collecting water that condenses upon the refrigerating coils and supplying the collected water to the reservoir to be stored until such time that the water is supplied to the quantity of gas contained in the confined space.

19. A method for humidifying a confined space wherein the confined space contains a quantity of a gas, the confined space including a reservoir for storing water, the reservoir being surrounded by outside air, said method comprising the steps of:

sensing the temperature and the humidity of the quantity of the gas in the confined space and providing water droplets to the quantity of the gas within the confined space to maintain the humidity within a predetermined range; and

sensing the temperature of the outside air surrounding the reservoir and sensing the temperature of the water stored in the reservoir and heating the reservoir when the temperature of the outside air is within a predetermined range and the temperature of the water stored in the reservoir is below a predetermined value.

20. The method as recited in claim 19 wherein the confined space further includes refrigerating coils for cooling the quantity of the gas, said method further comprising the step of collecting water that condenses upon the refrigerating coils and supplying the collected water to the reservoir to be stored until such time that the water is supplied to the quantity of gas contained in the confined space.

21. The method as recited in claim 19 wherein the humidity of the gas is to be maintained at a predetermined value, said method further comprising the steps of:

determining the difference between the sensed humidity and the predetermined value of humidity; and

providing water to the gas to proportionally decrease the difference between the sensed humidity and the predetermined value of humidity.

22. The method as recited in claim 21 wherein the confined space further includes refrigerating coils for cooling the quantity of the gas, said method further comprising the step of collecting water that condenses upon the refrigerating coils and supplying the collected water to the reservoir to be stored until such time that the water is supplied to the quantity of gas contained in the confined space.

23. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas and is surrounded by outside gas, said humidity control system comprising:

humidity sensor means for sensing the humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means for providing water to the confined space, said controlled droplet applicator means being constructed to receive a supply of water having a variable flow rate and being responsive to variation in the flow rate of the supply of water for varying the amount of water supplied to the confined space;

pump means for providing the supply of water to said controlled droplet applicator means, said pump means being responsive to a pump control signal for varying the flow rate of the supply of water being provided to said controlled droplet applicator means; and

data processing means for controlling the operation of said controlled droplet applicator means to maintain the humidity of the gas contained in the confined space above a predetermined value, said data processing means being responsive to said humidity sensor means for determining the amount of water that must be added to the gas contained in the container to increase the humidity above the predetermined value and for providing the pump control signal to vary the flow rate of the supply of water being provided to said controlled droplet applicator means so that the amount of water added to the gas contained in the container is proportionally controlled.

24. The humidity control system as recited in claim 23 further comprising inside temperature sensor means for sensing the temperature of the quantity of gas contained in the confined space, said data processing means being further responsive to said inside temperature sensor means for determining the amount of water that must be added to the gas contained in the container to increase the humidity above the predetermined value and for providing the pump control signal to vary the flow rate of the supply of water being provided to said controlled droplet applicator means so that the amount of water added to the gas contained in the container is proportionally controlled.

25. The humidity control system as recited in claim 23 wherein said controlled droplet applicator means is constructed to provide water droplets to the quantity of gas in the confined space and is responsive to a humidity control signal for varying the size of the water droplets supplied to the quantity of gas in the confined space, said data processing means being further constructed for providing the humidity control signal to vary the size of water droplets being added to the quantity of gas so that the amount of water added to the gas contained in the container is proportionally controlled.

26. The humidity control system as recited in claim 23 further comprising reservoir means for containing water supplied to said controlled droplet applicator means, said pump means being coupled to said reservoir means for pumping water from said reservoir means to said controlled droplet applicator means.

27. The humidity control system as recited in claim 26 further comprising heater means responsive to said data processing means for heating a portion of the water contained in said reservoir means.

28. The humidity control system as recited in claim 27 further comprising outside temperature sensor means for sensing the temperature of the outside gas surrounding the confined space, said data processing means being responsive to said outside temperature sensor means to control said heater means to supply heat to the water contained in said reservoir means when the temperature of the outside gas surrounding the confined space is below a first predetermined temperature.

29. The humidity control system as recited in claim 27 further comprising reservoir temperature sensor means for sensing the temperature of the water contained in said reservoir means, said data processing means being responsive to said third sensor means to control said heater means to supply heat sufficient to prevent the water contained in said reservoir means from freezing.

30. The humidity control system as recited in claim 26 wherein said pump means in further responsive to said pump control signal to pump water from said controlled applicator means to said reservoir means, said humidity control system further including outside temperature sensor means for sensing the temperature of the outside gas surrounding the confined space, said data processing means being responsive to said outside temperature sensor means for providing said pump control signal so that water is pumped from said controlled droplet applicator means to said reservoir means when the temperature of the outside gas surrounding the confined space is below a predetermined temperature.

31. The humidity control system as recited in claim 23 wherein said pump means further comprises a peristaltic pump.

32. A humidity control system for regulating the humidity of a confined space wherein the confined space substantially contains a quantity of gas and is surrounded by outside gas, said humidity control system comprising:

sensor means for sensing the temperature and humidity of the quantity of gas contained in the confined space;

controlled droplet applicator means for providing water to the confined space, said controlled droplet applicator means being constructed to receive a supply of water having a variable flow rate and being responsive to variation in the flow rate of the supply of water for varying the amount of water supplied to the confined space;

pump means for providing the supply of water to said controlled droplet applicator means, said pump means being responsive to a pump control signal for varying the flow rate of the supply of water being provided to said controlled droplet applicator means; and

data processing means for controlling the operation of said controlled droplet applicator means to maintain the humidity of the gas contained in the confined space above a predetermined value, said data processing means being responsive to said sensor means for determining the amount of water that must be added to the gas contained in the container to increase the humidity above the predetermined value and for providing the pump control signal to vary the flow rate of the supply of water being provided to said controlled droplet applicator means so that the amount of water added to the gas contained in the container is proportionally controlled.

33. A method for proportionally controlling the humidity of a quantity of gas contained in a confined space, said method comprising the steps of:

providing a controlled droplet applicator for providing water to the gas contained in the confined space wherein the controlled droplet applicator is constructed to receive a supply of water having a variable flow rate and responsive to the flow rate of the supply of water for varying the amount of water provided to the gas contained in the confined space;

determining the amount of water that must be added to the gas contained in the confined space to increase the humidity of the gas to a predetermined value; and

varying the flow rate of the supply of water to the controlled droplet applicator to proportionally vary the amount of water added to the gas contained in the confined space thereby to increase the humidity of the gas to the predetermined value.