US 20080000025 A1
A heat pump for use in a variable temperature pillow includes a housing with an inlet and a blower motor to draw in outside air to a two stage Peltier effect module that forms a sealed wall between a sub-cool side and a warm side of the housing. At the bottom of the housing are a pair of outlets and a condensate trap spanning across that facilitates condensate transfer from the cool side to the warm side for evaporation out of the warm side outlet. The heat pump also preferably includes a heat pipe from the warm side to the cool side to transfer heat and reheat the air (at a lower relative humidity) exiting through the cool outlet. An air conditioned pillowcase includes a pair of air impervious layers connected together forming a plenum with tubular spacer material inside and having a plurality of outlet vents around the perimeter. A multi-channel air duct connects the plenum to the heat pump, and further there is an optional noise cancellation system, both to minimize noise from operation of the heat pump.
1. A variable temperature pillowcase for use with a heat pump and a pillow comprising:
a pair of fabric layers connected together to form a plenum containing a layer of tubular spacer material;
the pillowcase having an opening on one end sized to receive the conventional pillow below the tubular spacer layer; and,
a ducting means mounted to extend inside the plenum from the heat pump.
2. The variable temperature pillowcase of
3. The variable temperature pillowcase of
4. The variable temperature pillowcase of
a noise cancellation system connected to the pillowcase comprising a microphone in communication with a processor in communication with a speaker for detecting a noise waveform and broadcasting a waveform 180 degrees out of phase with the noise waveform.
5. The variable temperature pillowcase of
6. The variable temperature pillow system comprising:
a pair of fabric layers connected together to form a plenum containing a layer of tubular spacer material and a plurality of outlet vents around the perimeter of the plenum;
the pillowcase having an opening on one end sized to receive a conventional pillow below the tubular spacer material; and,
a ducting means mounted to extend inside the plenum from the heat pump and the ducting means has multiple channels.
a batting layer above the tubular spacer material to enhance the user's comfort. and,
means releasably connected to the air ducting means for selectively cooling or heating a pressurized air stream.
7. The variable temperature pillow system of
a noise cancellation system connected to the pillowcase comprising a microphone in communication with a processor in communication with a speaker for detecting a noise waveform and broadcasting a waveform 180 degrees out of phase with the noise waveform a noise cancellation system connected to the pillowcase comprising a microphone in communication with a processor in communication with a speaker for detecting a noise waveform and broadcasting a waveform 180 degrees out of phase with the noise waveform.
This application is a Divisional of application Ser. No. 11/024,073 filed Dec. 28, 2004.
1. Field of the Invention
The present invention relates to pillows or other cushion-like devices that can be selectively cooled (or heated) by the user and an improved thermoelectric heat pump for use in such applications.
2. Description of the Related Art
Air-conditioned seats are a reality in many luxury-car brands being sold in the United States. The configuration and advantages of such seats were described in two of Steve Feher's recent patents, U.S. Pat. Nos. 6,263,530 and 6,085,369. These seats work satisfactorily such that they have become a popular option for Lexus, Lincoln and other automakers, but efforts are ongoing to improve the operating efficiency and compactness of the associated heat pumps to cool better, use less energy and occupy less space.
Besides merely reducing the temperature of the air within the seats and that bleeds through the seat covers, it would also be desirable to reduce the relative humidity of that air to enhance the user's comfort. To do so it is necessary to further cool the air below the dew point, dispose of the resulting condensation, and then reheat the air to a more comfortable temperature (but lower relative humidity) for distribution inside the seat. Preferably, the condensation is disposed of by evaporating it into the larger volume of air outside the seat. At the same time, it is desirable to reduce the electrical power requirements for the heat pump and decrease the volume of space required for the pump. These objectives are addressed by the subject disclosure which significantly improves the cooling element of today's air-conditioned seats.
As mentioned above, the technology of the present invention has other applications in addition to vehicle cushions, for example, bedding such as mattress pads and mattresses as mentioned in Steve Feher's '530 and '369 patents and as disclosed in his earlier U.S. Pat. No. 4,777,802. Additionally, Feher has been developing this technology specifically for use in pillows and pillow cases. Physiologically, the head is among the best places in the human body to remove heat from (or add heat to) because of the large amount of circulation in the head and scalp. Accordingly, effective cooling (or warming) of the human body can be achieved to a large extent by cooling (or warming) the head, providing improved user comfort in all types of weather, but especially hot, humid weather.
Conditioning the air inside a pillow or pillow case presents certain challenges, however. The pillow must be as quiet as possible since the user's ear may be in direct contact with the pillow. Further, attention should be paid to the sleeping surface of the pillow that it is kept as comfortable and aesthetically appealing as possible. These objectives are addressed as well in the disclosure that follows.
An improved thermoelectric heat pump includes a housing having an inlet opening at the top end, a blower motor mounted in an upper portion of the housing to draw in outside air and cause airflow into a lower portion of the housing. A thermoelectric device is mounted in the housing and forms a sealed wall between a cool side and a warm side of the lower portion of the housing and serves to channel the air flowing through the housing. A condensate trap is mounted at a bottom end of the housing and spans across the warm and cool sides of the housing, facilitating condensate transfer from the cool side to the warm side. The thermoelectric heat pump draws outside air in where it is cooled on the cool side and the heat transferred to the warm side, and cool air passes out the cool outlet and warm air out the warm outlet, and condensate transferred from the cool side to the warm side is evaporated out the warm outlet.
Preferably the thermoelectric device is a multi-stage Peltier effect module having a first and second stage. Preferably the first and second stages have conductor plates of approximately the same size and a shared conductor plate, and the first stage includes about 50% the volume of pellets as the second stage and the pellets are about evenly distributed across the first and second stages. The thermoelectric heat pump also preferably includes a heat pipe from the warm to the cool side of the lower portion of the housing, to transfer heat and warm up the air exiting through the cool outlet. Alternatively, a resistance-type heater may be used on the bottom end of the cool side. Preferably there are a number of heat exchanger fins projecting out from the thermoelectric device and the heat pipe.
One application of the thermoelectric heat pump is for a variable temperature cushion such as a connected seat and backrest, which has an interior volume defining a plenum that accepts pressurized conditioned air from an air duct from the cool outlet of the heat pump. The air duct and heat pump are preferably located proximate the middle portion of the cushion, and optionally there is a damper valve proximate this location to control the air flow within the cushion. The seating surfaces of the cushion cover are preferably air permeable material while the other sides are air impervious, and there is preferably a thin layer of padding beneath the cover. Inside the plenum is a layer of tubular spacer material to always allow air flow through the cushion, and there are preferably a plurality of vents in the plenum away from the middle portion of the cushion. The present invention may be sold as a variable temperature cushion or as kit of parts to convert a conventional cushion into a variable temperature one, or as an aftermarket cushion for placement atop a conventional vehicle seat.
Another application of the heat pump technology of the present invention is in the field of air-conditioned bedding, or variable temperature mattresses, mattress pads, pillows and pillowcases or the like. A variable temperature pillowcase includes a top and a lower air impervious layer connected together forming a plenum, further containing a tubular spacer layer and having a plurality of outlet vents around the perimeter of the plenum. The pillowcase preferably has an opening on one end sized to receive a conventional pillow below the tubular spacer layer. A multi-channel air duct connects the plenum to the heat pump to minimize the noise generated by the air flow through the hoses. Still further, there is an optional noise cancellation system including a microphone, a processor and a speaker for detecting a noise waveform and determining and broadcasting a waveform 180 degrees out of phase with the noise waveform.
These and other objects and advantages of the present invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings.
Initially referring to
Now primarily referring to
Now also referring to
Inside an upper portion 68 of the housing 52 is an integrated, single blower 70 including a blower motor 72 (held by a pair of support struts 73) and a number of impellor blades 74. A single, vane-axial blower 70 is shown but other types or quantities of blowers or any source(s) of pressurized air may be used. Further down in the housing 52 is a thermoelectric device 80, preferably a Peltier effect module, sandwiched between a pair of thin metallic baseplates 85 that along with an upper seal 82 and a lower seal 84 form a wall between a cool side 86 (main heat exchanger) and a warm side 87 (auxiliary heat exchanger) of the lower portion 69 of the housing 52. The single-stage Peltier module 80 is capable of lowering the temperature on the cool side 86 approximately 18 degrees Fahrenheit with a coefficient of performance or efficiency of approximately 50%. Attached to the baseplates 85 are approximately 36-42 very fine pitch metal heat exchanger fins 88 spaced apart and closely stacked one behind the other (approx. 18-21 fins per inch) to aid in transferring heat from the cool side 82 to the warm side 84. The fins 88 are preferably fabricated of copper (approx. 0.004 inches in thickness) or aluminum (approx. 0.006 inches in thickness) Across the bottom end 90 of the housing 52 is a condensation trap or wick evaporator 92 spanning from the warm side 86 to the cool side 87.
Having described the structure and hardware of the variable temperature cushion 30 and heat pumps 50, 100 and 120, their operation, function and use may be discussed. The cushion 30 is placed atop a conventional vehicle seat and the heat pump 50, 110 or 120 secured preferably at the bite line between the seat rest 32 and backrest 34, or alternatively forward of the seat rest 32 or above the backrest 34, using the appropriate air ducts 94, and 95 or 96. The heat pump 50, 110 or 120 is turned on by controls directly on the unit itself or a wired or remote control (not shown). The blower motor 70 causing the impellors 74 to rotate and draw in ambient air through the inlet opening 56 into the upper portion 68 of the housing. The air continues to travel downward into the lower portion 69 of the housing, either the cool side 86 (main heat exchanger) or the warm side 87 (auxiliary heat exchanger) and past the heat exchanger fins 88. The air on the cool side is chilled approximately 18-35 degrees Fahrenheit depending upon the type of Peltier module 80 or 110 in the unit, and the air on the warm side 87 heated approximately 40-50 degrees Fahrenheit.
Especially if the two-stage Peltier module 110 is used and the air cooled 35 degrees it should be well below the dew point and a good amount of condensate should form in the air. The condensate tends to accumulate on the fins 88 and then drip down onto the condensate trap or wick evaporator 92 and be retained therein. The cooler, drier air will pass out the cool outlet 60 and through the ducting 94, 95 or 96 and into the cushion 30. The moisture in the condensate trap 92 will travel along the bottom end 90 of the unit across into the drier, warm side 87, where the warm air passing by will cause it to evaporate out the warm outlet 66 and into the outside ambient air. Again, especially if the two-stage Peltier module 110 is used, it will be desirable to reheat the cool air back up to a more comfortable temperature about 18-20 degrees below ambient. This is accomplished by the cool air passing through a second heat exchanger lower set of heat exchanger fins 108, the heat coming from a passive heating element 102 (extending from the warm side 87) or alternatively an active resistance heater 122.
Next the cool air is flowing into the cushion 30 and through the tubular space layer 36 away from the heat pump 50, 110 or 120. Some of the cooled air may bleed through an air-permeable cushion cover 40 and/or the cooled air is released through small vents or ducting in the cushion 30 remote from the entry point of the cooled air. The damper valve 98 may be utilized, either in a wide open, partially closed or completely closed state as desired by the user, to control the flow of air and thereby the temperature of the seat rest 32 portion relative the backrest 34 portion of the cushion. Although the embodiments described thus far have been directed to a variable temperature cushion 30 for placement on a vehicle seat, the technology presented herein is applicable to cooled (or heated) mattress pads, futons, and other articles worn by persons such as helmets, vests, etc.
Now referring to
The air-conditioned pillow system operates and functions as follows. The multi-channel inlet nozzle 162 is connected to a heat pump and a stream of air-conditioned air, be it cool with reduced humidity or warm, is quietly supplied to the plenum 156 or enclosed space in the top portion of the pillowcase 150. The conditioned air travels through the tubular spacer layer 158 towards the outlet vents 164, thereby cooling (or warming) the top outer surface of the pillowcase. Optionally, the noise cancellation system samples a noise source through a miniature microphone 170 and sends it to a processing unit 172, which analyzes the noise and creates a waveform 180 degrees out of phase with the source which is broadcast through the speaker 174. The user is able to control the temperature of the pillowcase 150 in accordance with his or her preferences.
The present invention has been described in connection with preferred and alternate embodiments, but it is understood that modifications will occur to those skilled in the appertaining arts that are within the spirit of the invention disclosed and within the scope of the claims.