Ventilation – Having inlet airway – Including structure for mixing plural air streams together
Reexamination Certificate
2000-01-12
2001-04-10
Joyce, Harold (Department: 3742)
Ventilation
Having inlet airway
Including structure for mixing plural air streams together
C454S261000
Reexamination Certificate
active
06213867
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to an air handling system for a building and, in particular, such a system employing one or more induction units adapted to mix two air flows.
A variety of air handling systems for both large and small buildings are already known in the air handling industry. Air handling systems both for residential and commercial buildings can include the use of a central heating system that includes a fan unit capable of blowing heated air through air ducts that deliver the air to the various rooms of the building. When this system is used in conjunction with a central air conditioner, it is also capable of providing cool air to the various rooms through the air ducts. A relatively large fan is generally required for a large commercial or industrial building. Air silencers can be installed on both the inlet side and outlet side of these large fans to reduce the noise levels created by the operation of such fans.
It is also known to provide so called induction units that employ the venturi effect to mix together both return air from a building and primary air. The two air flows are mixed in a mixing chamber located adjacent an elongate air plenum with a primary air inlet at one end. Tapered nozzles extend into the mixing chamber and are connected to a wall of the air plenum. The return air from serviced space enters the mixing chamber which is flanked by the induction unit's coils on one side and five sides of the enclosure of the unit. There is an opening on the sixth side of the enclosure for entry of the return air. These units can typically be mounted on a wall of a room with the air plenum section located near the floor and the air outlet located at the top of the unit. Such induction units have at least several advantages including the ability to operate at very low noise levels since they do not employ any fans or similar air circulating devices. They can also be used in conjunction with both high pressure as well as low pressure air duct systems and they provide for a reasonably efficient mixing of the primary air and the return air.
Systems for delivering treated air to a room through an outlet located in the ceiling are already known. For example, U.S. Pat. No. 4,672,887 which issued Jun. 16, 1987 to Fred Sproul Sr. describes an air delivery system located above a horizontal ceiling in a dwelling. The air duct system delivers treated air to a valance/diffuser air system that can be located adjacent one wall of the dwelling. The conditioned or treated air is forced into the air delivery system by a blower of a conditioning unit such as a forced air furnace. At the wall the air is initially distributed lengthwise along an elongate horizontal chamber and then distributed through apertures in a downwardly direction. However, this known system does not use air induction units for mixing return air and primary air. In this known system the return air system is located beneath the floor of the dwelling.
More recent U.S. Pat. No. 5,577,958 issued to Mitsubishi Denki Kabushiki Kaisha in November, 1996 describes a ceiling-embedded cassette type air conditioner located above a decorative grate or panel through which return air can pass. A blower is located centrally in this air conditioner and it forces the return air through two or more heat exchangers located on the perimeter of the blower. The conditioned air is returned to the room through two or more outlets located at the ceiling level. Air directing plates can be positioned in the air outlets and these can direct the outflowing air to flow into the room at an angle to the horizontal. This known air conditioning system does not employ any induction unit that relies on the venturi effect and, because it employs a blower, it will be quite noisy when it is operating.
It is an object of the present invention to provide an air handling system for a building which employs at least two induction units and which is capable of mixing return air and primary air efficiently and quietly.
It is a further object of the present invention to provide an air handling apparatus for a building that includes two induction units, which apparatus can be manufactured and installed at a reasonable cost and can be operated and maintained at a low cost.
SUMMARY OF THE INVENTION
According to one aspect of the invention, an air handling system for a building having a horizontally extending ceiling and an enclosed space below this ceiling includes two induction units adapted for mounting adjacent the ceiling, each unit having an air mixing section forming a relatively long air mixing chamber and an elongate horizontally extending air plenum section mounted at an upper end of the air mixing chamber and having a primary air inlet formed therein. Air nozzles extend into the air mixing chamber of each unit and are mounted on a side of the air plenum section. Each air nozzle has an inlet end that is open to an interior chamber of the air plenum section. The air mixing section has an air outlet formed at a lower end thereof and a side air inlet for permitting return air to flow through a side of the air mixing section and into the air mixing chamber. Supporting members are also provided for mounting the two induction units so that each air mixing section extends at a substantial acute angle to the ceiling and is located adjacent the ceiling. During use of this system, the return air is drawn by the venturi effect created by the nozzles into each air mixing chamber. Each induction unit is capable of delivering a mixture of primary air, that passes through the plenum section and the nozzles, and return air through its air outlet to the enclosed air space.
Preferably a heat exchanging coil unit is mounted adjacent to the side of at least one air mixing section so that return air flowing through the side air inlet first passes through the coil unit in order to be heated or cooled thereby.
According to a further aspect of the invention, there is provided a combination of a building structure having an enclosed space and an air handling system capable of providing a mixture of primary air and return air to the enclosed space. This combination includes a horizontally extending ceiling and walls forming the building structure and defining the enclosed space. Two induction units are mounted adjacent the ceiling and each unit has an air plenum section with a primary air inlet and an air mixing section forming an air mixing chamber and mounted on a side of the air plenum section. Air nozzles extend into each air mixing chamber and are mounted on the side of the air plenum section. These air nozzles each have an inlet end that is open to a primary air high pressure plenum chamber in the air plenum section. A side return air inlet in one side of the air mixing section permits return air to flow into the air mixing chamber from the enclosed space. Each air mixing section has an air outlet at an end thereof furthest from its plenum section. There are also supporting frame members mounting the two induction units adjacent the ceiling so that each air mixing section extends down from the air plenum section to its air outlet and extends at an acute angle to the ceiling. During use of this system, the return air from the enclosed space is drawn by a venturi effect created by the nozzles into each air mixing chamber and the two induction units deliver the mixture of primary air and return air through their air outlets to the enclosed space.
Further features and advantages will become apparent from the following detailed description of a preferred embodiment, taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 1138470 (1915-05-01), Hackney
patent: 4672887 (1987-06-01), Sproul
patent: 5324229 (1994-06-01), Weisbecker
patent: 5350337 (1994-09-01), Kondo et al.
patent: 5577958 (1996-11-01), Kumekawa et al.
M & I Induction Unit Brochure, 1996, pp. 1 to 3,8 to 10, 13, 14.
Fisher Tom
Granek Gerhard
Yazici Muammer
Air Handling Engineering Ltd.
Baker & Daniels
Boles Derek S.
Joyce Harold
LandOfFree
Venturi type air distribution system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Venturi type air distribution system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Venturi type air distribution system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2538644