Patent Application
20120052789
The invention at hand relates to either heating or cooling the air in a building, especially with a floor area having a multiple of persons working therein. The invention is directed 1) primarily to the personal comfort and health of a person working at a desk by directing conditioned air to the immediate vicinity of the person or persons present at those workstations and by giving those workstations the use and control of the conditioned air, and 2) to provide displacement air ventilation to the surrounding area, while at the same time providing for a cleaner environment using less energy, and 3) to provide other services required. This method of total space conditioning is known as task/ambient conditioning.
In the field of heating and cooling, generally known as “air conditioning” there are known problems causing discomfort to the occupants in the building or a room. Inefficiencies in the system result in excessive operating costs in the operation of the building and control of the present system. Also, present systems tend to have a poor indoor air quality (IAQ) because of the mixing effect and exacerbate the spread of infections by cross-contamination from person to person.
U.S. Pat. No. 374,424 discloses a system for supplying fresh air to the environment of an auditorium and wherein the air blows directly to chair which is occupied by a person without any mechanical control.
U.S. Pat. No. 1,194,527 shows the ventilation of a class room through a ventilated floor panel and is further distributed into a desk where the pupil is sitting. The pupil may have some control over the amount of air flowing to or through the desk. In both the above cited patents, the air is not conditioned or modified as to heat, cold or relative humidity.
U.S. Pat. No. 2,140,829 describes an air conditioning system wherein there is cooling of high ceiling rooms by providing a stratum of cooled and dehumidified air in their lower levels of the room up to the height of the occupants without a personal control over the flow of the air without considering the relatively large cost and the complications of treating all of the air in the room, that is, the heating and cooling and without the benefit of displacement ventilation to maintain the surrounding room with no room air control.
U.S. Pat. No. 2,341,125 illustrates a way of ventilating a desk at a workstation by simply mounting a fan within the rear of the desk and by blowing air at the person and by giving the person working at the desk somewhat of a control of the fan by positioning the same or by controlling the speed of the air flow. Air is not conditioned.
U.S. Pat. No. 2,507,634 teaches the ventilation of restaurant equipment by supplying air to and from restaurant tables. The person or persons seated at the tables have no control over the flow and/or direction of the flow of the air, and there is no displacement ventilation for the remaining space.
U.S. Pat. No. 2,572,120 shows a ventilated table having a fan mounted in a horizontal position which is emitting air in a horizontal direction and the air flows out of the lateral sides of the table without the benefit of displacement ventilation.
U.S. Pat. No. 2,616,617 illustrates a ventilated table similarly constructed as the table shown in the immediately above cited patent without displacement ventilation.
U.S. Pat. No. 2,734,990 discloses a desk as a workstation having a combination fan and heater mounted therein. The fan blows the conditioned air (heat) directly at the person sitting at the desk. The direction of the air is adjustable by tilting the fan in one direction or the other and the level of the heat is adjustable by way of a rheostat but there is no displacement ventilation.
U.S. Pat. No. 2,835,186 discloses an air conditioning system wherein there are upstanding air emitting columns receiving air through ducts in the floor system. It is considered to be a local or spot air conditioning system and there is no displacement ventilation system.
U.S. Pat. No. 2,877,990 discloses a novel building structure embodying a multi-cellular load supporting floor having an air distributing and an electrical wiring system wherein both the heated and the cooled air and the electric wires are distributed through selected ones of the cells in the floor.
U.S. Pat. No. 3,322,055 teaches the elimination of duct work in a building by adding fan driven diffusers in the ceiling whereby the air in the chamber in the ceiling may be used as an unpressurized distribution chamber. Again, there is no description of an air displacement ventilation system.
U.S. Pat. No. 3,516,374 shows the use of a double plenum air conditioning system which creates a space between a structure and the floor of the roof above the building and the double plenum is divided by a horizontal partition into an upper part and a lower plenum and a supply of air is fed to one of the plenum and return air is withdrawn from the other of the plenums. The supply of air can be hot or cold or neutral. Inlets and outlets connect the plenums through the slab to the room below or through to the room above, but there is no personalized control or a displacement ventilation system.
U.S. Pat. No. 4,035,018 discloses a system whereby conditioned air is distributed through a floor plenum to a multiple of chairs having an air supply connected to each of the chairs to expel the conditioned air into the general environment of the room. The occupants of the chairs have no control over the speed and the direction of the air flowing to the chairs and there is no displacement ventilation or provision for space heating or cooling.
U.S. Pat. No. 4,135,440 illustrates an air conditioning system including both ceiling and floor plenums and each of the plenums has individual air outlets diffusing air into the room between the plenums. In addition, there are individual elongated air outlet tubes suspended from the ceiling plenums or upstanding from the floor plenum. Each of the outlet tubes can be directed against a person sitting at a workstation. The respective person has control over the direction of the air flowing from the outlets, but without the benefit of a displacement ventilation system or control of the space thermal load.
U.S. Pat. No. 4,378,727 shows an open office space system including a plurality of freestanding workstation which are constructed of vertical panels and are removably mounted to an upper board member to direct cooling air to a user of the organization permitting its use in a convenient manner in various environments.
Another prior art air conditioned workstation is known under the word “CLIMADESK”. It is described as a plenum which is installed under the top of the desk. The air plenum has an inlet to receive conditioned air from an air conditioning unit being placed apart from but adjacent to the desk. The air conditioning unit receives fresh air from the outside of the building through an air intake vent. The air plenum installed under the top surface of the desk is directing conditioned air toward a person sitting at the desk. The conditioned air is exiting toward the person by way of two front louvers and is further directed upwardly from the top surface of the desk in front of the person sitting at the desk. The temperature of the conditioned air can be controlled by way of a thermostat located on a front panel of the desk. This kind of an arrangement greatly reduces the mobility of such a workstation and thereby eliminates an effective arrangement of all of the workstations in an open office concept. There is no provision for air displacement ventilation to provide conditioning for the space.
German published specification (Offenlegungsschrift) No. 24 07 448 discloses a workstation in the form of a desk receiving conditioned air by way of a flexible hose through the floor having ducts therein. The occupant at the desk has no control over the flow of the air with regard to direction and/or speed and no displacement ventilation for space control.
German published specification (Offenlegungsschrift) No. 27 19 570 discloses a similar system as was disclosed in the German publication above. In this arrangement, the conditioned air is supplied by way of ducts located below the floor of the open office area. From there the conditioned air is funneled to upstanding tube located at each of the workstations. The conditioned air is blown into the room at a location above the desk surface at each of the workstations. The occupant of the workstation has some control over the direction and the speed of the air flowing through the outlets of the upstanding tubes, but no displacement ventilation.
German published specification (Offenlegungsschrift) 29 38 702 is similar to both German publications discussed above and does not add any more knowledge to the already known prior art.
Japanese Patent No. 61-11535 discloses an air conditioning system having a floor plenum installed over a slab of a building. The conditioned air is driven by a fan into a hollow partition situated over an opening in the floor. Conditioned air may exit into the room at a higher elevation than the height of the desk. At the bottom of the floor whereupon the desk is placed, there is a further air outlet which is directing conditioned air to the feet of a person sitting at the desk. It appears that the person has very little control over the volume, speed and direction of the conditioned air entering the vicinity of the desk. None of the above cited references disclose a system wherein a stand-alone unit is located in the vicinity of a workstation or provides for room control by displacement ventilation.
An object of the invention is to present a system for distributing various building services, including task/ambient air conditioning, throughout an open plan office environment in a most efficient and economical way. The inventive system provides local workstation access to various building services, simultaneous air conditioning to the space at large through displacement ventilation and individual control over personal supply air, and energy savings. In a building, large or small, or in individual rooms or at workstations, the control of temperature, air flow, humidity and the like leaves many persons dissatisfied with the, condition of their individual environments. Different persons have different levels of metabolism and, therefore, different needs for comfort. The inventive system provides a means to satisfy various individual thermal comfort needs and the space as a whole at the same time. Total air supply is controlled to satisfy the total cooling or heating requirement.
Also, different locations in a building or on a floor, or even in a single room or in the vicinity of a workstation, are not satisfactorily heated or cooled, that is, air conditioned, which will give rise to complaints about discomfort and illness, resulting in absenteeism and, of course, loss of productivity and wasted energy.
Further, conventional air conditioning systems generally require expensive duct work installations, usually in ceilings or floors or both. This causes unnecessary heating or cooling of unused space. For example, the approximately six feet of space that is occupied in a room having a 12 foot ceiling has an unoccupied space of approximately six feet, and the air in that space can be warmer and thereby save energy. The above mentioned duct work also increases an energy demand for the movement of the air through the ducts and presents difficulties in cleaning.
Prior art and known systems with slab floor and/or wall mounted air outlet grilles limited the location of workstations, furniture and equipment to positions at locations which would enhance the flow of air. Such prior art systems also created complaints of discomfort caused by high or low air velocities, or high or low temperatures, depending on the location of the air outlet grilles. Also, air conditioning outlet grilles and the ducts associated therewith frequently need to be removed to accommodate changes in air conditioning loads, or a rearrangement of the work space or individual workstations in an open office layout, and do not provide for displacement ventilation.
While workstations may be economically beneficial with regard to the amount of floor space being used, the use of partitions creates an impediment to the flow of the conditioned air throughout the room. Conditioned air flows freely in the area above and around workstations; however, within the workstations or between the room dividers or partitions, there is limited means for providing the workstation occupant with an acceptable flow of conditioned air. Workers often become uncomfortable or even ill, which in turn decreases productivity and/or causes absenteeism.
Consequently, in the field of heating and cooling there exists a need for providing a flow of conditioned air directly to or near a person sitting at or in the vicinity of a workstation, without creating a draft, as well as to occupants of the surrounding area. More particularly, there exists a need for a workstation to be so equipped whereby the occupant can individually control and obtain the amount of conditioned air supplied within the workstation while maintaining a desirable amount of conditioned air to surrounding areas. The amount and direction of conditioned air flow within the workstation is controlled by the occupant to maximize his or her comfort level, well being, health and productivity, while maintaining a desirable amount of conditioned air for surrounding areas by the displacement ventilation system (not by mixing, which causes cross-contamination).
Conventional room dividers for workstations may supply conditioned air to workstations, with continuous air flows through an air flow grille at about the height where the worker is sitting, but the worker has very little control over the flow of air or its direction. Such room dividers consist of hollow spaces being created by panels that are spaced from each other by a predetermined distance to define an air flow there between, but there is no provision for displacement ventilation or effective personal control. The hollow room divider is placed on an opening in the floor, which floor is spaced above the concrete slab of the building which constitutes the building floor to thereby form a large or major air plenum. This air plenum, therefore, is formed by a slab of the building and the raised floor being spaced above the slab of the building. The air plenum is charged with conditioned air (hot or cold). Applicants' prior U.S. Pat. Nos. 4,646,966; 4,860,642; 5,135,436; 5,238,452 and 6,318,113 are directed to conditioned air being supplied through a floor plenum and from there distributed to individual workstations through various forms of air delivery. All the noted patents above operate in various satisfactory manners, but there is still room for improvements. In all the known prior art patents as well as applicants' own patents there is a tendency of the air that is introduced into the workstations and various open spaces to create air streams or air whirls that have a detrimental effect on the overall indoor air quality within the room where persons are working. This circulating air does not contribute to the cleanliness of the ambient air. On the contrary, the circulating air will pick
Displacement ventilation is an innovative concept for the supply of conditioned air and ventilation of buildings. It uses the natural buoyancy of warm air to provide ventilation and comfort. In a displacement ventilation system, supply air is introduced to the space at or near floor level, at a low velocity and at a temperature only slightly below the desired room temperature. The cooler supplied air “displaces” the warmer air, creating a zone of fresh cool air at the occupied level. Heat and contaminants produced by the activities in the occupied space are carried to the ceiling, where they are exhausted, thus providing cleaner space.
Displacement Ventilation systems are typically more energy efficient and quieter than conventional overhead systems. They also provide better ventilation efficiency and improve indoor air quality. Displacement Ventilation systems are appropriate in spaces such as class rooms or conference rooms with high ventilation requirements. They are also being used with great success in an open office space architecture.
In order to achieve the relatively lower speed supply air flow necessary for effective displacement ventilation, the supply air outlets must be of larger area to maintain sufficient volume of air flow to meet cooling load requirements. It is often difficult to find sufficient surface area in a typical office environment to accommodate larger outlets. The inventive movable stand-alone terminal meets this need by providing adequate surface area in one of its side panels where none exists without the terminal, such as next to workstations or in room locations away from walls.
Experience has shown that in an office layout stand-alone units may be equipped with more features. For example, it is desirable that one stand-alone unit can serve at least two adjacent workstations that are independent of but located in the vicinity of the stand-alone unit. This could be accomplished by one stand-alone unit having two personal air outlets or discharge areas operating in different directions.
One type of office architecture can have air in underfloor plenums that are at zero air pressure relative to the ambient air. In this type of installation, the stand alone-unit can have an air fan installed therein that will pull the conditioned air from the underfloor plenum. The basic principle would be the same, which is, that a stand-alone unit can be positioned anywhere desired. It merely would be a task of moving a respective modified tile from the floor and positioning the stand-alone unit right over some opening in a different location, as will be explained below. In certain buildings which have no underfloor plenum, the conditioned air would be supplied through ducts lying on a floor in an inconspicuous area, or by ducts or channels embedded in the floor concrete slab.
It has also been shown that different damper systems can be used instead of the dampers explained below, such as opposed blade dampers. Such dampers would allow a more fine tuned control over the flow of the air through the stand-alone unit.
Modem and up-to-date workstations require quite a few convenience outlets, such as telephone jacks, computer outlets or data ports, coaxial cables and regular electrical outlets that are commonly in use on regular workstations. One object of the stand-alone unit can be to have installed therein a terminal or connector panel or box. The respective cable connections or feeders can be supplied from conduits located in the underfloor plenum, or could be supplied through conduits located and embedded in the concrete slab. The electrical system, as suggested above, could also incorporate a local relay to override a central shut-off, including fusing, and a shut off to turn off the stand-alone unit altogether. An override control allows an after hours reset of the stand-alone unit. This system can also include a motion detector that should shut down the unit when a person just leaves the area and turns it on again when that person returns. This system would fall under the idea of saving energy.
It has also been found that under certain environmental circumstances, it is desirable that heat should be supplied to a certain workstation instead of cooled air. This could be accomplished by incorporating a heater in the stand-alone unit. Such heat could be supplied by a resistance heater, a convection heater or an infrared heater.
The unit 1 has several controls therein. There is a damper 35 within the unit that controls the air flowing into the front of the unit. The damper control consists of plates 36 and 38 that can move relative to each other. The plate 36 has openings 37 therein and the plate 38 has openings 39 therein. Once the plates 36 and 38 are moved relative to each other, the openings 37 and 39 will more or less overlap each other to control the amount of air (arrow D) passing through these openings 37 and 39. The volume control consists of a rotatable sheet of metal such as a vane 34 that is controlled by the knob 5 located on top of the unit 1. The rotational direction of the vane 34 is indicated by the arrow C. The front outlet of the unit has several louvers 33 therein that will control the flow of air either up or down and left to right.
On the front panel of the cabinet 4 various controls could be located that would have an impact on the whole operation of the system. At 65 there is shown a relay that could influence the control and operation of the system at the will of the operator to save power. Then there could be a motion detector 66 that would simply turn off the operation of the system when a person leaves the premises and turn it on again upon return of that person. The knob 64 indicates a control knob for the opposed blade louvers, which are operated by a well known mechanism. The representation 67 indicates the presence of a smoke or heat detector, the structure of which is well known. While most office layouts are tobacco smoke-less environments, it is desirable to include a smoke detector in case of a fire within the stand-alone unit or in the vicinity thereof.
