1. Field of the Invention
This present invention relates to improved convective cooling and heating of seats, mattresses, mattress pads and other articles used as a cushioning device.
2. Description of Related Art
There are many applications and situations where it is desirable to provide for convective cooling or heating of various articles including seats, mattresses and other articles used for supporting individuals while either sitting or laying down on the article. Many of the conventional devices that have been used suffer from serious drawbacks. As one example, the resistance heated type prior art mattresses and cushions do not provide for cooling or ventilation, a major disadvantage in many parts of the world that lack adequate air conditioning. Moreover, the conventional devices are very inefficient and lack adequate control to adjust the heating or cooling temperature to satisfy the needs of the user. In addition, because of the believed negative impact on the environment, certain materials, such as Freon used for cooling purposes, are being phased out for use in air conditioning systems in many countries.
In U.S. Pat. No. 6,085,369 by Steve Feher there is disclosed a selectively cooled or heated cushion and apparatus therefore and in U.S. Patent Publication No. 2006/0137099 also by Steve Feher, published Jun. 29, 2006, a convective cushion with a positive coefficient of resistance heating mode is disclosed. While each of the Feher '369 patent and the Feher '099 application is a substantial improvement over other known and conventional prior art techniques, there is believed to be room for improvement in apparatus and systems that provide selectively variable temperature air to convective cushions in a wide variety of applications, including home, office and in vehicles, including increasing the overall efficiency of operation. Thus, a need exists for improved systems and methods for convective cooling and heating of seats, mattresses, mattress pads and other articles.
A convective seating and sleeping apparatus, systems and methods for controlled convective cooling and heating for seats, mattresses, mattress pads and other articles. In one or more embodiments, the invention includes a convective cushion that provides selectively controlled convective cooling and heating delivered from a power unit and blower, such as a Stirling cycle heat pump or a Peltier thermoelectric device. The invention has air flow structures within the cushion including tubular spacer material. The invention includes remote activation and operation of the convective cushion by a telecommunications unit.
In one or more embodiments, the invention includes a convective cushion having removable modular pockets that when assembled together form the convective cushion. The pockets contain tubular spacer material and are arranged to deliver air of a selectively variable temperature and quantity to an air permeable top cover. Further embodiments include the use of a divider to create different sections within the cushion with different air inlets to provide for two or more temperature zones on the cushion for different users. Additional embodiments use tubular spacer material that has been cut to length along a cut line and along a film placed adjacent to the cut line that effectively limit the undesired unraveling of fibers of the tubular spacer material along said cut line.
Embodiments of the invention include the use of deep styling pleats that run longitudinally or laterally through the convective cushion. The invention includes a series panel air flow structure and a parallel panel air flow structure to deliver the selectively variable temperature air throughout the convective cushion without the pleats interrupting the air flow. Further embodiment include improved heating and cooling devices and their operation including a Stirling cycle heat pump and a thermoelectric device to provide the selectively variable temperature air to the convective cushion.
Embodiments of the invention include an improved Stirling cycle heat pump with a magnetic bearing powered by a permanent magnet that eliminates the input power requirement for a gas bearing on every stroke of the piston. One of the disadvantages of conventional gas bearings that is overcome is the fact that, when the conventional bearing is not energized sufficiently by the motion of the piston, such as when the machine is being started or stopped, the gas bearing function is significantly diminished, allowing the piston to “land” against the piston bore. This has been handled in the past by using a non-stick, low friction coating on the inside of the bore and on the piston itself. Although wear has been reduced significantly, it was not completely eliminated in these conventional systems.
The second and most important disadvantage overcome by the present invention is that the gas bearing requires a power input to function. The power input is in the form of the pumping action of the piston reciprocating in the cylinder. Part of the force applied to the piston is used to pump the gas bearing on each stroke. As these machines operate in the region of 60 Hertz or more, this is a loss mechanism that reduces the efficiency of the Stirling device. Because of the elimination of the gas bearing pumping requirement, the Stirling device will operate more efficiently and because piston “landing wear” on start-up and shut-down is substantially eliminated, the reliability of the Stirling cycle device will be improved.
Further embodiments of the invention include a Stirling device or a Peltier type thermoelectric device that includes a reheater and optionally a hygrometer and sensor to control the relative humidity of cooled air delivered to the convective cushion. Other embodiments provide for a method for remote control of the convective cushion in a vehicle by transmitting a control signal from a telecommunications unit located remotely from the vehicle to a receiver in the vehicle to activate delivery of cooling or heated air to the convective cushion or other vehicle article such as the steering wheel.
Other and further advantages and embodiments will appear to persons skilled in the art from the written description and the drawings herein.
As shown in
Each of the pockets 22 contains tubular spacer material 30. The present inventor's U.S. Pat. Nos. 6,085,369 and 6,263,530 pioneered the use of tubular spacer fabric as an air flow structure for seats, mattresses, mattress pads and other articles of furniture that can be sat on or laid down upon. Although one embodiment of the invention utilizes the same tubular spacer fabric as described in the inventor's issued U.S. Pat. Nos. 6,085,369 and 6,263,530, it is within the scope of the present invention to utilize other air flow structures such as Muller Textile's 3 Mesh or Strahle and Hess' assembled woven fabric and other air flow structures, however there may be substantially reduced levels of performance when compared to the tubular spacer fabric disclosed in the above issued U.S. patents.
The pockets 22 secure the multiple sections of the tubular spacer material 30 close together while still allowing air to flow from one end of the plenum 12 to the other end of the plenum 12 through pockets 12 via the tubular spacer material 30. The pockets 22 may be arranged so that the longitudinal axes of the tubular spacer material in the pockets 22 are all aligned to allow substantially uninterrupted flow of air. If the pockets 22 were made of standard cotton sheeting, as the upper and lower layers are made, the pressure drops across the pocket walls between the tubular spacer material 30 layers would be too high and functional air flow within the plenum 12 would not be possible using a small, light, cost-effective and quiet main blower.
The use of multiple pockets 22 containing tubular spacer material 30 in one or more embodiments instead of one single mattress sized panel allows for the tubular spacer material 30 to be easier to handle in smaller pieces and it is generally not feasible to launder a single mattress size piece of tubular spacer material 30 in a standard washing machine. A single queen size piece of tubular spacer material 30 is not impossible to handle, but is much more difficult to handle than smaller pieces, even if laundering by washing in a shower or bathtub or a large washtub. For larger beds, such as King, California King, and larger, it may be more convenient to divide the plenum 12 into more pockets 22 to facilitate shipping, handling and laundering and these embodiments are within the scope of the present invention also.
As shown in
In one or more embodiments, the blower 46 delivers air to the air inlet nozzle 40 which may include a flexible hose portion as shown in
In one or more embodiments, the face plate 48 which is removable from the blower 46 and secured to the blower 46 by plastic fittings, snap-on connectors or other securing mechanisms that allow the face plate 48 to be removed, all of which are known to persons skilled in the art and included within the scope of the present invention. The face plate 48 may cover all or as shown merely a portion of the blower 46, and be a single color such as a neutral color or a dark color or may be a combination of colors. The face plate 48 may be made of one or more materials including plastic, wood or a combination of materials. The face plate 48 may also be a design such as a wood appearing veneer as selected by the user to present a more attractive appearing article to persons viewing the blower 46. Embodiments of the present invention allow a user to selectively change the face plate 48 as desired for a variety of color, color combinations and design arrangements that the user may wish to select.
In one or more embodiments shown in
In one or more embodiments, the thermistor or thermocouple 50 may be placed on the underside of the top cover 34 of the embodiment shown in
In further embodiments of the invention, the thermistor or thermocouple 50 is of the miniature type in order to minimize sensor mass and enable more rapid and sensitive reaction to changes in cover cloth temperature.
In cooling mode, if the user is large and hot, it will take longer for the sensor to cool down because the user's body heat will prevent the sensor from cooling down to the temperature of the air flowing by on the inside of the tubular spacer material 30. But if the user is small and relatively cool, or if the user has cooled down after sitting on the seat or lying on the mattress pad, the sensor will begin to read more of the internal air temperature, and this change in value can be interpreted as a signal to reduce cooling power in order to avoid overcooling.
The embedded thermocouple or thermistor 50 is applicable to both cooling and heating modes in the improved Peltier thermoelectric type convective cushion 10 because heating mode is a function of input power to the thermoelectric device and the air flow volume through the heat pump.
Also as shown in
It can be appreciated in
For example,
In one or more embodiments, two or more hog rings 70 are used on each Lister wire assembly 68. The Lister wire assembly 68 pulls a cover 74 down deeply into the gap, creating a deep styling pleat 62 that is securely anchored to the seat base foam 72. Additional hog rings 70 may also be located along the side edges as shown to create deep styling pleats on the sides of the cushion as well.
Other embodiments of the invention include seat rests that can be configured in the same manner for lateral and longitudinal deep pleats. An advantage of the parallel arrangement is that the air temperature change is substantially the same in all of the panels, whereas in the series arrangement, the temperature change will diminish as the air flows from one panel to the next because heat is absorbed from the user in cooling mode and is transferred to the user in heating mode.
As shown in
As shown in detail in
In one or more embodiments, the piston 116 is made of a lightweight material other than that used for the magnetic ring and known to persons skilled in the art in order to minimize the magnetic flux, and hence bearing size, required to levitate and maintain the piston 116 and magnetic piston ring 158 on center within the annular structure of the magnetic bearing assembly and the cylinder 150 during reciprocation. The present invention includes the use of such lightweight materials. The piston 116 moves essentially in pure reciprocating motion, with little if any angular moment, which is ideal for a magnetic bearing, particularly of the passive type, as described here, and does not require auxiliary control coils or an active feedback controller to maintain bearing and piston concentricity.
In an embodiment of the invention, a surface coating or treatment resulting in a very low coefficient of friction is used. For example, in the event that the Stirling device 110 is subjected to a sharp bump or high acceleration force and the piston is momentarily displaced within the magnetic bearing and the cylinder bore, low friction surfaces will minimize undesirable wear during a “hard landing” of the piston.
In one or more embodiments, a ferrofluid 160 is placed in the magnetic circuit gap 162 between the stator pole 130 and piston driver coil 132 as shown in
Ferrofluid is a liquid well known to persons skilled in the art that contains ferromagnetic particles in suspension so that the fluid itself acquires magnetic properties and behaves as though it is magnetic. The magnetic field of the stator magnet holds the Ferrofluid in place, while allowing the Ferrofluid to exhibit low viscosity and shear strength for low pumping losses due to the reciprocating motion of the piston driver coil. The Ferrofluid 160 increases the magnetic permeability of the air gap and increases magnetic field strength and efficiency. Another advantage of the Ferrofluid in the air gap is that heat generated in the piston driver coil is more efficiently conducted across the Ferrofluid to the stator pole and then outward to the ambient environment than it is with a gap of helium separating the piston driver coil from the stator pole. This helps to reduce temperature rise in the piston drive coil, which reduces electrical resistance changes as a function of temperature and makes for increased coil insulation life and greater reliability.
In further embodiments, the invention allows a user to activate and control a Variable Temperature Steering Wheel, (“VTSW”), which is the subject of the inventor's U.S. Pat. No. 5,850,7641. In additional embodiments, the VTSW may be energized simultaneously with the vehicle seat using the present invention, in order to provide a steering wheel grip surface temperature that corresponds with the seat mode.
For example, in warm weather, especially with bright sunlight impinging upon the interior surfaces of a vehicle, both the steering wheel grip surface and seat surfaces may become relatively very hot. It would then be desirable to cool these surfaces down to a pleasant temperature, preferably before entering the vehicle, to avoid heat stress.
In embodiments of the invention, both the steering wheel and the seat can be left in cooling mode while driving in order to maintain vehicle occupant thermal comfort while using little, if any, conventional space air conditioning. This saves on fuel and reduces emissions and improves vehicle performance, as vehicle air conditioning systems typically require approximately 3-5+ horsepower, and the single convective cushion+VTSW combination requires not more than approximately 80 watts total for the Stirling Cycle type convective cushion with VTSW, and approximately 140-160 watts for the Peltier thermoelectric convective cushion with VTSW. Each additional convective cushion requires approximately 20 watts for the Stirling cycle device and approximately 80-100 watts for the Peltier thermoelectric device.
In the embodiments shown schematically in
Cooling air that contains water in vapor form to below the dew point precipitates a percentage of that water vapor as condensate. The amount of condensate depends on how far below the dew point the air is cooled. After cooling down to the dew point, or sub-cooling below the dew point, the air can be said to be saturated with vapor, or at 100% relative humidity, because it is holding all of the water that is theoretically soluble in that volume of air, as vapor, at that temperature and barometric pressure.
The greater the drop in temperature for a given starting water vapor content, or relative humidity, the more condensate will be precipitated out of the air when that air is cooled. The greater the subsequent rise in temperature, (re-heat), the lower the relative humidity of that air will be because some of the water that was originally entrained in the air as water vapor has been removed as condensate, and as the temperature of that air rises it's capacity for holding water vapor increases again. However, since some of the water vapor that was originally entrained in that air has been precipitated out as condensate, the relative humidity of that air is now lower.
One procedure is to first drop the conditioned air temperature enough, if the starting relative humidity is higher than desired, to get rid of some of the water vapor, then raise it enough to reduce its relative humidity, (relative humidity is simply the amount of water vapor contained in a given unit volume of air divided by the theoretical maximum amount of water vapor that can be contained in that volume of air at that given temperature and barometric pressure), without heating it up beyond the ideal or desired comfort temperature. This process is desired to provide true air conditioning, wherein the relative humidity of the environment is controlled in addition to the temperature.
In one or more operating embodiments of the invention, a basic operational logic includes the following:
1. If the hygrometer, (relative humidity gauge or sensor), senses relative humidity below 50%, for example, (or any other desired relative humidity), at any output air temperature, the re-heater is not energized.
2. The re-heater is not energized in heating mode, unless ambient temperature is so low that it is necessary or desirable.
3. If re-heat is necessary in either cooling mode or heating mode, the controller energizes the re-heater on a curve until the desired relative humidity is reached for a given selected air temperature, or until the selected temperature is maintained at a predetermined relative humidity.
In further embodiments, a condensate trap (not shown) may be provided, however it is in one or more embodiments simply a small volume container with a small aperture that allows condensation produced in the main heat exchanger to drain out without allowing ambient air to leak into the cooling mode air stream. This can be accomplished in one or more embodiments by using a drain hole of approximately 0.10-0.20″ diameter plugged with a short length of wicking material (not shown) that blocks air flow while wicking liquid into the condensate trap chamber. The wick can also be extended in length and extended to reach to surface of the auxiliary heat exchanger in order to provide some evaporative cooling to the auxiliary heat exchanger, reducing its temperature and thereby increasing the coefficient of performance (“COP”) of the Stirling heat pump device by reducing the overall temperature change between the cold and hot sides.
In additional embodiments of the invention, the re-heater 172 is configured to provide heated air for a heating mode that delivers heated air to the convective cushion 10 in addition to re-heat in a cooling mode as described above.
In cooling mode, the Stirling Cycle heat pump cools air that is drawn through the main heat exchanger 171, (main heat exchanger 171 as also shown in
In addition to lowering the relative humidity of the cushion air, other functions that may be provided include:
1. The thermal transfer efficiency of heat from the auxiliary heat exchanger 173 to the ambient air is increased because reducing the temperature of the ambient air increases the temperature change between the auxiliary heat exchanger and the ambient air.
2. Because of increased thermal transfer efficiency, and a lower auxiliary heat exchanger temperature, the total heat pump temperature change from hot side to cold side is reduced, increasing the COP of the Stirling heat pump device, which increases the energy efficiency of the Stirling Cycle heat pump device. In one or more embodiments, a positive temperature coefficient (“PTC”) device 175 and heat exchanger 171 shown in
The divider 190 is relatively impermeable to air and extends from the top surface 14 to the bottom surface 18 as shown in
In embodiments of the invention, the divider 190 substantially prevents lateral mixing or mingling of the different air flows, such as from air inlet nozzle 192 and second inlet nozzle 194 as shown in
After the adhesive has cured, the tubular spacer material 30 is cut down the middle of the tape or film leaving a margin of film 200 on each side of the cut line 202 as shown in
The cooled air results in a lower auxiliary heat exchanger temperature, which lowers the overall temperature difference between the cold side and the hot side of the Peltier device, increasing its coefficient of performance and energy efficiency. The relative humidity of the cooled air delivered to the convective cushion (as shown in arrow 222) is thereby reduced.
A condensate wick 224 is shown communicating between the main heat exchanger 218 and the auxiliary heat exchanger 214. Condensation produced in the main heat exchanger 218 in cooling mode is drawn to the auxiliary heat exchanger 214 by the wick 224, without allowing the two air streams to co-mingle, providing whatever condensate is available to the auxiliary heat exchanger 214. The condensation evaporates on the relatively warm auxiliary heat exchanger producing an additional cooling effect which increases the COP of the thermoelectric device 210 and improves its energy efficiency further beyond what is provided by the counter-regenerative auxiliary air cooling system.
In further embodiments, if a thermoelectric device has sufficient capability, such as, for example, that described in the inventor's U.S. Pat. No. 6,855,880 entitled Modular Thermoelectric Couple and Stack, it is useful to control main blower air relative humidity by using the active reheater to raise cooling air temperature and thereby reduce its relative humidity if desired.
Since the main exchanger 218 is hot in heating mode, the warmer the auxiliary heat exchanger 220 is, the lower the overall temperature change, hence the higher the COP, or energy efficiency of the Peltier thermoelectric heat pump. In one embodiment, the device 210 is designed with enough capacity to produce the desired net heating mode air temperature even with a bit of cooling provided by the regenerator.
While the present invention has been described with regards to particular embodiments, it is recognized that additional variations of the present invention may be devised without departing from the inventive concepts in the claims and the invention includes the full breadth and scope of the claims including all equivalents.
This application is a continuation-in-part of pending application Ser. No. 11/225,605 filed on Sep. 13, 2005 which is a continuation-in-part of pending application Ser. No. 11/024,073 filed on Dec. 28, 2004, the disclosures of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | 11225605 | Sep 2005 | US |
Child | 11824260 | Jun 2007 | US |
Parent | 11024073 | Dec 2004 | US |
Child | 11225605 | Sep 2005 | US |