Claims
- 1. An apparatus for creating an air curtain for a cooler having a refrigerated compartment, the apparatus comprising:
a) at least one air moving device drawing air in from the refrigerated compartment and emitting said air; b) at least one motor powering the air moving device; c) a control system including a sensor detecting whether a door of the cooler is open, the control system providing power to operate the motor when the sensor detects that the door of the cooler is open; and d) one or more air discharge nozzles directing air emitted by the at least one air moving device to create a curtain of air that flows horizontally across at least a portion of a doorway of the cooler normally closed by said door, the one or more nozzles being configured to be mounted adjacent to a doorway of the cooler such that air is discharged at an angle of at least 5° in relation to a plane of the doorway.
- 2. The apparatus of claim 1 wherein the nozzles are configured to be mounted by being attached to a blower housing that has a flat side, with the nozzles being directed to discharge air at an angle of at least 5° in relation to said flat side.
- 3. The apparatus of claim 1 wherein the sensor comprises an electromechanical switch detecting the opening of the door.
- 4. The apparatus of claim 1 wherein the one or more air discharge nozzles discharge air at a velocity of at least 200 feet/min.
- 5. The apparatus of claim 1 wherein the one or more air discharge nozzles discharge air at a velocity of between 500 and 2000 feet/min.
- 6. The apparatus of claim 1 wherein the at least one air-moving device comprises one or more tangential blowers.
- 7. The apparatus of claim 1 wherein the at least one air-moving device comprises one or more centrifugal blowers.
- 8. The apparatus of claim 1 wherein the at least one air-moving device comprises four blowers powered by two dual shaft motors.
- 9. The apparatus of claim 1 wherein the at least one motor is a permanent split capacitance (PSC) motor.
- 10. The apparatus of claim 1 wherein the at least one motor is a solid state commutated (SSC) motor.
- 11. The apparatus of claim 1 wherein the at least one motor is a C-frame motor.
- 12. The apparatus of claim 1 wherein the at least one motor is a shaded pole motor.
- 13. The apparatus of claim 1 wherein the at least one motor is a DC motor.
- 14. The apparatus of claim 1 wherein the at least one motor is a split phase motor.
- 15. The apparatus of claim 1 wherein the at least one motor can achieve a speed of at least 1000 rpm.
- 16. The apparatus of claim 1 wherein the at least one motor can achieve a speed of at least 1500 rpm.
- 17. The apparatus of claim 1 wherein the one or more air discharge nozzles have a rectangular discharge area configuration with a width of between about ½ and 5 inches.
- 18. The apparatus of claim 1 wherein the one or more air discharge nozzles have a rectangular discharge area configuration with a width of between ¾ and 2 inches.
- 19. The apparatus of claim 1 wherein the air moving device and the one or more nozzles are designed and positioned to blow air only across a bottom portion of the doorway, the bottom portion comprising between about ⅔ and about ¾ of the height of the doorway of the cooler.
- 20. The apparatus of claim 1 wherein the control system turns the air moving device on instantaneously when the sensor senses that the door is opened.
- 21. The apparatus of claim 1 wherein the control system cuts the power to the least one motor when the sensor senses that the door is closed.
- 22. The apparatus of claim 1 wherein the one or more air discharge nozzles are mounted directly adjacent to the air moving device.
- 23. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of between 5° and 45° in relation to a plane of the doorway.
- 24. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of between 5° and 40° in relation to a plane of the doorway.
- 25. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of between 10° and 38° in relation to a plane of the doorway.
- 26. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of between 15° and 36.5° in relation to a plane of the doorway.
- 27. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of between 20° and 35° in relation to a plane of the doorway.
- 28. The apparatus of claim 1 wherein the one or more air discharge nozzles are configured to be mounted adjacent to a doorway such that air is discharged at an angle of about 30° in relation to a plane of the doorway.
- 29. A method of operating a cooler having insulated walls defining a refrigerated compartment, a doorway in one of the walls having a normally closed door, and a refrigeration system cooling the cooler, the method comprising the steps of:
a) starting a motor powering one or more blowers in conjunction with the door being opened; b) the one or more blowers drawing air from the refrigerated compartment and emitting the air via one or more nozzles to produce a horizontal air curtain when the motor drives the one or more blowers, the one or more nozzles discharging the air at an angle of at least 5° in relation to a plane of the doorway; and c) stopping the motor by cutting off power to the motor in conjunction with the door being closed.
- 30. The method of claim 29 wherein the motor is started as soon as the door is opened.
- 31. The method of claim 29 wherein the motor is an electric motor and electrical current to the motor is cut off as soon as the door is closed.
- 32. The method of claim 29 wherein the air flows horizontally across a lower portion of the doorway.
- 33. The method of claim 32 wherein the horizontal air curtain blows across approximately the lower ⅔ to ¾ of the area of the doorway.
- 34. The method of claim 29 wherein the air curtain reduces the amount of cool air escaping from approximately the lower ⅓ of the area of the doorway compared to a doorway without an air curtain on a cooler operating under the same internal and external temperature conditions.
- 35. The method of claim 29 wherein the air curtain reduces the amount of warm air entering through approximately the upper ⅓ of the area of the doorway.
- 36. The method of claim 29 wherein the air is drawn directly into the one or more blowers from the refrigerated compartment.
- 37. An apparatus mounted inside of a refrigerated compartment of a walk-in cooler for creating a horizontal air curtain for a doorway of the cooler comprising:
a) four 12″ long tangential blowers wherein each blower circulates the cool air from within the cooler and operates at the rotation speed of about 1650 RPM, and has a wheel with diameter of about 65 mm.; b) two {fraction (1/25)} horsepower dual shaft PSC motors, each motor being positioned between and powering two blowers; c) an air discharge nozzle mounted adjacent each blower to discharge an air stream at an angle of about 30° from a plane of a doorway of the cooler, the nozzles having a discharge area of rectangular cross section and about 1⅛ inches wide; d) the nozzles directing the stream of air emitted by the blowers to create a horizontal air curtain that flows across approximately the lower ¾ of the area of the doorway and inhibiting cold air from escaping approximately the lower ¾ of the doorway of a cooler, the nozzles emitting air at a velocity such that the air still has a velocity of about 250 feet/min at a far side of the doorway; e) a control system, including an electromechanical switch detecting whether the door of the cooler is open, that turns the blowers on when the sensor senses that the door is open and off when the sensor senses that the door is closed; and f) a safety guard covering the blowers, the motors and the nozzles for protection of people using the cooler.
- 38. A cooler having a refrigerated compartment defined by insulated walls, a doorway in one of the walls and a door normally closing the doorway, the cooler also comprising an air curtain device comprising:
a) one or more blowers drawing air from the refrigerated compartment and emitting said air; b) one or more motors powering the one or more blowers; c) a control system comprising a sensor detecting whether the door of the cooler is open, the control system providing power to operate the one or more motors when the sensor detects that the door is open; and d) one or more air discharge nozzles directing air from the one or more blowers to form a curtain of air that flows horizontally across at least a portion of the doorway only when the door is open and at an angle of at least 5° in relation to a plane of the doorway.
- 39. The cooler of claim 38 wherein the curtain of air reduces the amount of warm air entering the cooler via approximately the upper ¼ of the doorway compared to a doorway without an air curtain on a cooler operating under the same internal and external temperature conditions.
- 40. The cooler of claim 39 wherein the curtain of air reduces the amount of warm air entering the cooler via approximately the upper ½ of the doorway.
- 41. The cooler of claim 38 wherein the door is about 34″ wide and about 78″ tall.
- 42. The cooler of claim 38 wherein the one or more air discharge nozzles direct the curtain of air at an angle of between about 5° and about 45° in relation to a plane of the doorway.
- 43. The cooler of claim 38 wherein the blowers comprise at least two blowers mounted with a vertical axis of rotation adjacent the doorway of the cooler.
- 44. The cooler of claim 38 wherein the sensor comprises an electro-mechanical switch.
- 45. The cooler of claim 44 wherein the switch forms part of an electrical circuit in the control system and turns power on when the door of the cooler is opened.
- 46. The cooler of claim 44 wherein the switch forms part of an electrical circuit in the control system and turns power off when the door of the cooler is closed.
- 47. The cooler of claim 38 wherein the air curtain reduces energy consumption of the cooler by reducing the amount of cold air escaping through the doorway of the cooler when the door is open.
- 48. The cooler of claim 38 wherein the doorway is wider than 60 inches and the curtain comprises two air streams blowing towards each other.
- 49. The cooler of claim 38 wherein the air curtain device reduces refrigerated compartment energy consumption by at least 4.5% compared to a cooler that does not include the air curtain device, as measured when the refrigerated compartment is empty, the ambient temperature is 80° and the cooler is set to maintain a temperature of 35°, and when the door is opened periodically for 3 minutes and closed 17 minutes between each time it is opened during an eight hour test period.
- 50. The cooler of claim 38 wherein the air curtain device reduces the rise in the cooler's average temperature when the door is left open for 15 minutes by at least 2.5° F. compared to not using the air curtain device, when tested on an empty refrigerated compartment of about 935 cubic feet.
- 51. The cooler of claim 38 wherein the one or more blowers are covered with a safety guard for protection of the people using the cooler.
- 52. The cooler of claim 38 wherein the angle of the one or more air discharges nozzles is not adjustable.
- 53. The cooler of claim 38 wherein the width of the one or more air discharge nozzles is not adjustable.
- 54. The cooler of claim 38 wherein the speed of the one or more blowers is not adjustable.
- 55. The cooler of claim 38 wherein the cooler is a walk-in refrigerator.
- 56. The cooler of claim 38 wherein the cooler is a walk-in freezer.
- 57. The cooler of claim 38 wherein the air curtain extends across approximately the lower ¾ area of the doorway.
- 58. The cooler of claim 38 wherein the one or more nozzles are positioned directly adjacent to the one or more blowers.
- 59. The cooler of claim 59 wherein the angle of the air curtain emitted from the one or more nozzles serves to balance the convection pressure from temperature differences from inside the cooler to the environment surrounding the cooler.
- 60. The cooler of claim 38 wherein the one or more nozzles cause the air to spread out at an angle of between about 2° and 15° as it is discharged from the blower.
- 61. A method of designing an energy efficient cooler comprising:
a) identifying parameters specific to a given cooler design that have a bearing on the characteristics of a horizontal air curtain that will economically inhibit cold air from leaving the cooler when a door to the cooler is open; and b) selecting a blower and an air discharge nozzle, and configuring the blower and nozzle such that i) the volume of air emitted by the blower, ii) the angle of the air discharge nozzle compared to plane of a doorway of the cooler and iii) the velocity of an air stream emitted from the air discharge nozzle are selected to minimize power consumption required to operate the combined cooler and air curtain.
- 62. The method of claim 61 wherein the width of the discharge nozzle and the velocity of air are chosen to fit a specific door size.
- 63. The method of claim 61 wherein the angle of the discharge nozzle is designed to ensure that air leaving the nozzle counters the cool air attempting to leave the cooler when the door is open.
- 64. The method of claim 61 wherein the velocity of air emission is designed to ensure that air leaving the nozzle counters the air attempting to leave the cooler when the door is open.
- 65. The apparatus of claim 1 wherein the temperature of the air discharged by the one or more nozzles is the same over the height of the air curtain.
- 66. The apparatus of claim 1 wherein the velocity of the air discharged by the one or more nozzles in emission is substantially the same over the height of the air curtain.
- 67. The apparatus of claim 1 wherein the angle at which the air discharged by the one or more nozzles is generally uniform over the height of the air curtain.
- 68. The apparatus of claim 1 wherein the air is drawn directly into the air moving device from the refrigerated compartment.
- 69. The apparatus of claim 1 wherein the air moving device comprises multiple blowers each mounted so as to have a vertical axis of rotation.
- 70. The apparatus of claim 1 wherein the air moving device is located in close proximity to the one or more air discharge nozzles such that no duct is disposed between the air moving device and the one or more air discharge nozzles.
- 71. A compact apparatus for creating a horizontal air curtain for a doorway of a cooler comprising:
a) at least one blower; b) at least one motor powering the blower; c) at least one air discharge nozzle; d) the at least one motor and blower being vertically mounted together in a stacked manner; e) a sensor detecting whether a door of the cooler is open; and f) a control system that provides power to operate the motor when the sensor detects a door-open condition.
- 72. The apparatus of claim 71 wherein the device has four blowers and two PSC motors, and all the components of the device fit within an assembly having a volume of less than 1 cubic foot.
- 73. The apparatus of claim 72 wherein the assembly is designed for installation in an existing cooler to retrofit the cooler with a horizontal air curtain.
- 74. A method of conserving energy during operation of a walk-in cooler comprising the steps of:
a) providing a walk-in cooler having a refrigeration system and insulated walls with a doorway in one of the walls and a door normally closing the doorway with a horizontal air curtain apparatus, the air curtain apparatus comprising
i) at least one air moving deice; ii) at least one motor powering the air moving device; iii) a control system that detects when the door is open and provides power to operate the at least one motor only when the door is open; and iv) one or more air discharge nozzles directing air emitted by the at least one air moving device to create a curtain of air that flows horizontally across at least a portion of the doorway; and b) operating the air curtain apparatus such that the energy consumed to create the air curtain is less than the energy saved as the refrigeration system has to do less work because air flow in and out of the doorway is inhibited by the air curtain when the door is open.
- 75. The method of claim 74 wherein the walk-in cooler is a walk-in cooler that has previously been used and the method involves retrofitting the cooler by installing the horizontal air curtain apparatus.
REFERENCE TO EARLIER FILED APPLICATION
[0001] This application claims the benefit under 35 U.S.C. § 119(e) of the filing date of Provisional U.S. Patent Application Serial No. 60/381,304, filed May 17, 2002, which is hereby incorporated by reference.
Provisional Applications (1)
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Number |
Date |
Country |
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60381304 |
May 2002 |
US |