Convective cushion with positive coefficient of resistance heating mode

• US 20090126110A1
• Filed: 01/06/2009
• Published: 05/21/2009
• Est. Priority Date: 09/13/2005
• Status: Active Grant

• Current Assignee: Steve Feher
• Original Assignee: Steve Feher
• Inventors: Feher, Steve
• Granted Patent: US 7,937,789 B2
• Time in Patent Office: Days
• US Class Current: 5/423
• CPC Class Codes: A47C 21/044 with active means, e.g. by using air blowers or liquid pumps
• CPC Class Codes: A47C 21/048 for heating
• CPC Class Codes: A47C 27/008 protecting against wear or damage
• CPC Class Codes: A47C 27/082 with non-manual inflation, e.g. with electric pumps
• CPC Class Codes: A47C 31/006 Use of three-dimensional fabrics
• CPC Class Codes: A47C 7/74 for ventilation, heating or cooling actuated by rocking the chair A47C3/02
• CPC Class Codes: A47C 7/742 for ventilating or cooling A47C31/116 takes precedence
• CPC Class Codes: A47C 7/748 for heating
• CPC Class Codes: B60N 2/5635 coming from the passenger compartment
• CPC Class Codes: B60N 2/5657 blown towards the seat surface
• CPC Class Codes: Y10S 5/941 Blanket with forced air flow

Abstract

A cushion heated convectively using a positive temperature coefficient of resistance type resistive heating includes a mattress pad, seat or the like with a bottom surface secured around its perimeter to an air permeable top surface, forming a plenum and containing tubular spacer material or other air flow structure therein. The plenum is connected to a power unit housing a blower, a heating module and a controller unit. The heating module includes a PTC type heating element. A remote control is provided, and a foldable antenna attachable to the convective unit facilitates wireless communication with the controller unit. The user resting atop the cushion controls the blower and heating module to deliver air of a desired temperature and quantity to the cushion and through the top surface.

Claims

1. A convective cushion comprising:

a plenum defined by a laterally extending bottom surface and a laterally extending top surface secured around a perimeter extending transversely therebetween to contain an open air space, an air flow structure formed of flexible open cell material disposed in the air flow space, said air flow structure spacing the top surface from the bottom surface, said top surface adapted for convective air flow delivered from said air flow structure over substantially the entire top surface responsive to a flow of air blown laterally through said plenum, said top surface being sufficiently impervious to air to retain greater air pressure within the air flow space, said air flow structure maintaining a substantial portion of said flow of air within a venting air flow in a coplanar direction laterally between said top and bottom surfaces to be directed laterally outward through said plenum proximate said perimeter, a portion of the flow of air venting through said top surface;

a power unit in fluid communication with the plenum, and housing a blower in fluid communication with a heating element;

a controller unit in communication with the blower and heating module;

whereby a user resting atop the cushion is able to control the blower and heating module to deliver air of a desired temperature and quantity into the cushion to said air flow structure, to deliver said air of desired temperature and quantity to said top surface producing the convective air flow over substantially the entire top surface.

2. The convective cushion of claim 1 wherein the heating element is one or more positive temperature coefficient type heating modules.

3. The convective cushion of claim 1 wherein the power unit is located outside the plenum and the plenum has an opening at one end, and further comprising an air duct with one end sized to be received into the plenum opening and a second end extending to the power unit.

4. The convective cushion of claim 2 wherein the heating modules comprise a heat exchanger in conduction with the positive temperature coefficient type heating module.

5. The convective cushion of claim 4 wherein the heat exchanger comprises a base plate coupled in thermally conductive manner to the positive temperature coefficient type heating element, and a plurality of heat exchanging fins.

6. The convective cushion of claim 5 wherein the heating element is sandwiched between a pair of the base plates coupled in thermally conductive manner and the plurality of heat exchanging fins.

7. The convective cushion of claim 6 further comprising a seal between the base plates to minimize air flow from passing therebetween.

8. The convective cushion of claim 1 further comprising a remote control in communication with the controller unit.

9. The convective cushion of claim 1 wherein the controller unit includes a speed control for the blower.

10. The convective cushion of claim 1 further comprising one or more vents in the perimeter of the plenum.

11. The convective cushion of claim 1 wherein the bottom surface of the plenum is generally air impermeable.

12. The convective cushion of claim 1 wherein the plenum is adapted to be inserted within a vehicle seat.

13. The selectively-controlled convective cushion of claim 1 wherein the air flow structure is tubular spacer material.

14. A mattress pad comprising:

a plenum defined by a laterally extending air permeable top surface secured around a perimeter extending transversely therebetween, the plenum containing an air flow space, an air flow structure formed of flexible open cell material and having an opening at one end disposed in the air flow space, said air flow structure below the top surface, said top surface adapted for convective air flow delivered from said air flow structure over substantially the entire top surface responsive to the flow of air blown laterally into said plenum, said top surface being substantially impervious to air to retain greater air pressure within the air flow space, said air flow structure guiding a substantial portion of said flow of air to maintain a venting air flow passing in a coplanar direction laterally below said top surface to be directed laterally outward through said plenum perimeter, a portion of the flow of air venting through said top surface;

a power unit housing a blower in fluid communication with a heating module and the plenum;

a controller unit in communication with the power unit; and

,

whereby a user resting atop the mattress pad is able to control the blower and heating module to deliver air of a desired temperature and quantity to the pad and to said air flow structure, to deliver said air of desired temperature and quantity to said top surface to produce the convective air flow over substantially all of the top surface.

15. The mattress pad of claim 14 wherein the heating module comprises a positive temperature coefficient type heating element in conduction with a heat exchanger.

16. The mattress pad of claim 15 wherein the heat exchanger comprises a base plate coupled in thermally conductive manner to the positive temperature coefficient type heating element, and a plurality of heat exchanging fins.

17. The mattress pad of claim 16 wherein the heating element is sandwiched between a pair of the base plates coupled in thermally conductive manner thereto and the plurality of heat exchanging fins.

18. The mattress pad of claim 17 further comprising a seal between the base plates to minimize air flow from the blower from passing therebetween.

19. The mattress pad of claim 14 further comprising a remote control in communication with the controller unit and including a speed control for the motor.

20. The mattress pad of claim 14 further comprising one or more vents in the perimeter of the plenum.

21. The mattress pad of claim 14 wherein the air flow structure is tubular spacer material.

22. The mattress pad of claim 14 wherein the mattress pad is incorporated into a mattress.

23. A cushion having effective and safe temperature control comprising:

a plenum containing an air flow space and a top surface sufficiently impervious to air to retain greater pressure within the air flow space while allowing only a portion of air to vent from the air flow space through the top surface; and

,

means for moving the air in the air flow space adjacent the top surface such that heat is transferred between the air and the top surface.

24. The cushion having effective and safe temperature control of claim 23 further comprising means for controlling the means for moving the air in the air flow space.

25. The cushion having effective and safe temperature control of claim 23 wherein the plenum contains an air flow structure formed of flexible open cell material disposed in the air flow space supporting the top surface of the plenum from excessive deformation when a user rests atop the cushion.

26. The cushion having effective and safe temperature control of claim 23 further comprising a power unit housing a heating element in fluid communication with the plenum.

27. The cushion having effective and safe temperature control of claim 26 wherein the heating element is one or more positive temperature coefficient type heating modules.

28. The cushion having effective and safe temperature control of claim 23 wherein the power unit is located outside the plenum and further comprising one or more ducts connecting the one or more heating modules to the plenum.

29. The cushion having effective and safe temperature control of claim 23 further comprising one or more vents in the plenum.

30. The cushion having effective and safe temperature control of claim 23 wherein the cushion is in the form of a mattress pad.