Temperature controlled vehicle seats

A seat temperature control system having a temperature controlled seat for use in a vehicle is disclosed. The temperature controlled seat may comprise a seat bottom, a seat back and an air conditioning system. The seat bottom includes a bottom heat exchanger fluid coil configured to direct a cooling fluid therethrough from a bottom inlet end to a bottom outlet end. The seat back includes a back heat exchanger fluid coil configured to direct the cooling fluid therethrough from a back inlet end to a back outlet end. The air conditioning system includes a coils inlet line in fluid communication with the bottom inlet end and the back inlet end, and a coils outlet line in fluid communication with the bottom outlet end and the back outlet end. The air conditioning system provides cooling fluid to the coils and receives cooling fluid from the coils.

BACKGROUND OF INVENTION

The present invention relates generally to temperature controlled vehicle seats, and more particularly to vehicle seats having coils therein for passing refrigerant or coolant therethrough.

In order to improve the comfort of passengers in automotive vehicles, some have supplemented the vehicle heating, ventilation and air conditioning (HVAC) system with heated or cooled seats. For example, some seats include an electric element that heats up when a current is passed through it. Others route some of the cooled air from the HVAC system through the seats. While others employ thermoelectric based seat heating and cooling. These arrangements are meant to improve the passenger comfort by supplementing the heating or cooling provided by the vehicle HVAC system. But these seat systems do not achieve the heating and/or cooling as efficiently as is desired.

SUMMARY OF INVENTION

An embodiment contemplates a temperature controlled seat for use in a vehicle. The temperature controlled seat may comprise a seat bottom, a seat back and an air conditioning system. The seat bottom extends in a generally horizontal direction and includes a bottom heat exchanger fluid coil therein, with the bottom heat exchanger fluid coil configured to direct a cooling fluid therethrough from a bottom inlet end to a bottom outlet end. The seat back is located adjacent to the seat bottom and extends in a generally vertical direction and includes a back heat exchanger fluid coil therein, with the back heat exchanger fluid coil configured to direct the cooling fluid therethrough from a back inlet end to a back outlet end. The air conditioning system includes a coils inlet line in fluid communication with the bottom inlet end and the back inlet end, and a coils outlet line in fluid communication with the bottom outlet end and the back outlet end, with the air conditioning system configured to provide the cooling fluid to the coils inlet line and receive the cooling fluid from the coils outlet line.

An embodiment contemplates a seat temperature control system for a vehicle. The seat temperature control system may include a first temperature controlled seat and a first air conditioning system. The first temperature controlled seat includes a first seat bottom and a first seat back, with at least one of the first seat bottom and the first seat back including a first heat exchanger fluid coil therein configured to direct a cooling fluid therethrough from a first inlet end to a first outlet end. The first air conditioning system includes a first coils inlet line in fluid communication with the first inlet end and a first coils outlet line in fluid communication with the first outlet end, with the first air conditioning system configured to provide the cooling fluid to the first coils inlet line and receive the cooling fluid from the first coils outlet line.

An embodiment contemplates a seat temperature control system for a vehicle comprising a temperature controlled seat and a refrigeration unit. The temperature controlled seat includes a seat bottom and a seat back, at least one of the seat bottom and the seat back includes a heat exchanger fluid coil therein configured to direct a refrigerant therethrough from an inlet end to an outlet end. The refrigeration unit is mounted adjacent to at least one of the seat back and the seat bottom and includes an expansion device in fluid communication with the inlet end, a condenser in fluid communication with the expansion device, and an electrically driven compressor in fluid communication with the condenser and the outlet end.

An advantage of an embodiment is that the cooling and/or heating of vehicle seats is achieved relatively efficiently, thus providing additional passenger comfort with high efficiency. That is, improved time to occupant comfort is achieved with reduced energy consumption versus previous seat thermal management systems. Also, the cooling and/or heating of the seats can be accomplished before an occupant enters the vehicle, thus further improving passenger comfort.

DETAILED DESCRIPTION

Referring toFIGS. 1-2, a temperature controlled seat, indicated generally at10, is shown. The temperature controlled seat10includes a seat bottom12and a seat back14. The seat bottom12may include a seat fan15for moving air through the seat bottom12. Alternatively or in addition, a seat back fan (not shown) may also be employed. The seat back14includes heat exchanger fluid coils16, and the set bottom12includes heat exchanger fluid coils18. A coils inlet line20connects to the fluid coils16,18for directing a fluid, such as refrigerant or a liquid coolant, into the fluid coils16,18. A coils outlet line22connects to the fluid coils16,18for receiving the fluid from the coils16,18. The coils inlet and outlet lines20,22connect to refrigerant systems (not shown inFIGS. 1 and 2), which will be discussed below relative to the various embodiments.

FIG. 3illustrates a first embodiment of a seat temperature control system24having a pair of temperature controlled seats10. The seats10may be, for example, a vehicle right front seat and left front seat. Of course, other numbers of seats10may be employed in this system24. Each seat10has a seat bottom12, with heat exchanger fluid coils18, and a seat back14, with heat exchanger fluid coils16. The coils inlet and outlet lines20,22for the left and right seats10connect, respectively, to left and right miniature refrigeration units26, which form part of the seat temperature control system24.

Each miniature refrigeration unit26includes a refrigerant compressor28, a condenser30, a fan32for moving air through the condenser30, and an expansion device34. The compressors28may include integrated electric motors or, alternatively, separate electric motors (not shown) may drive each of the compressors28. Each fan32may also be driven by an electric motor. The expansion devices34may be, for example, orifice tubes, thermal expansion valves, or capillary lines.

The operation of the seat temperature control system24will now be discussed with reference toFIGS. 1-3. Upon a vehicle occupant requesting seat cooling for a particular seat10, the compressor28and fan32for that seat10are activated. A vehicle HVAC system does not have to be operating for the seat cooling to take place. Refrigerant compressed by the compressor28flows through the condenser30where heat is removed. The refrigerant then flows through the expansion device34, dropping the temperature of the refrigerant, and then flows through the coils inlet line20to the heat exchanger fluid coils16,18, of the seat back14and seat bottom12, respectively. The heat exchanger fluid coils16,18in effect act as an evaporator in a refrigerant loop, absorbing heat from the seat10. The seat fan15may also be activated in order to facilitate heat transfer. The cooled seat10, then, cools the vehicle occupant. Since each seat10has its own miniature refrigeration unit26, each may have separate controls to allow for different rates of cooling for each seat10.

Also, since the vehicle HVAC system does not need to be operating, the seat cooling may be accomplished as a preconditioning event prior to occupants entering the vehicle. For example, preconditioning of the seat10may occur simultaneously with a remote engine start feature on a hot day or may be a separate remotely activated feature.

On the other hand, if the HVAC system is operating during seat cooling, then the amount of seat cooling can be used as a factor to adjust the main HVAC system. That is, if the seat is at a certain temperature due to seat cooling, then the HVAC control temperature may be offset to account for this. Thus, the power consumption of the HVAC system may be reduced.

FIG. 4illustrates a second embodiment. Since this embodiment is similar to the first, similar element numbers will be used for similar elements, but employing 100-series numbers. While only one temperature controlled seat110is shown, more than one seat in a vehicle may be included as part of the seat temperature control system124.

In this embodiment, the seat bottom and back112,114still include heat exchanger fluid coils118,116, respectively. And, the heat exchanger fluid coils116,118are connected to the miniature refrigeration unit126. This miniature refrigeration unit126, however, can now operate as a heat pump, thus providing both cooling and heating to the seat110. The refrigeration unit126includes the expansion device134, condenser130and fan132. The refrigeration unit126also includes the compressor128connected to a four-way valve138, allowing for the reversal in direction of flow of the refrigerant through the fluid coils116,188, expansion device134and condenser130, thus allowing for seat heating in addition to seat cooling. While this refrigeration unit126may add more cost and complexity versus the cooling only unit ofFIG. 3, it provides the additional capability of heating the seat110.

FIG. 5illustrates a third embodiment. Since this embodiment is similar to the first, similar element numbers will be used for similar elements, but employing 200-series numbers. While only one temperature controlled seat210is shown, more than one seat in a vehicle may be included as part of the seat temperature control system224.

In this embodiment, the heat exchanger fluid coils216in the seat back214have a separate coils outlet line240connecting to the miniature refrigeration unit226. This coils outlet line240includes a seat back shut-off valve242that can selectively stop the flow of refrigerant through the seat back fluid coils216. Also, the coils outlet line222extending from the fluid coils218in the seat bottom212includes a seat bottom shut-off valve244that can selectively stop the flow of refrigerant through the seat bottom fluid coils218. This provides added flexibility for the temperature controlled seat210in that a seat occupant may wish to only cool the seat back214or the seat bottom212rather than both.

The seat temperature control system224of this embodiment may include the additional functionality of the heat pump refrigeration unit described with reference toFIG. 4. In addition, to reduce the cost, one may employ only one of the two shut-off valves242,244—even though the functionality is now reduced somewhat.

FIG. 6illustrates a fourth embodiment. Since this embodiment is similar to the first, similar element numbers will be used for similar elements, but employing 300-series numbers. This seat temperature control system324is shown with four temperature controlled seats310, a right front seat, a left front seat, a right rear seat and a left rear seat. The number of seats310shown is only an example, and other numbers of seats may be included in the seat temperature control system324.

In this embodiment, the refrigerant for the temperature controlled seats310is provided by the vehicle refrigerant system326. The vehicle refrigerant system326includes a compressor328, a condenser330and a fan332, but the refrigerant flowing from the condenser330does not all flow through an expansion device346leading to an HVAC module evaporator348. Some of the refrigerant is directed to individual expansion devices334, each connected to the coils inlet line320for the corresponding seat310. Each seat310also includes fluid coils318in the seat bottom312and fluid coils316in the seat back314and may include a seat fan315.

While this embodiment minimizes the number of compressors and condensers in the vehicle (versus the previously discussed embodiments) and thus the cost, seat cooling is limited to operating only when the overall vehicle refrigerant system326is operating.

FIG. 7illustrates a fifth embodiment. Since this embodiment is similar to the fourth, similar element numbers will be used for similar elements, but employing 400-series numbers.

As with the fourth embodiment a vehicle air conditioning system426is employed rather than miniature refrigeration units for each seat in the seat temperature control system424. However, this air conditioning system426is a secondary loop type of system. That is, the refrigerant (primary) loop452may be contained entirely within an engine compartment454of a vehicle456. The primary loop452may include a compressor428, a condenser430, a fan432and an expansion device434. Also, a refrigerant-to-liquid heat exchanger458is part of the primary loop452and a secondary (coolant) loop460.

The secondary loop460employs a liquid, such as, for example, engine coolant, which transfers its heat to the refrigerant in the refrigerant-to-liquid heat exchanger458. The secondary loop460may also include a liquid pump462, a coolant inlet line464that directs the liquid to a chiller466and to coils inlet lines420, coils outlet lines422that direct coolant back to the refrigerant-to-liquid heat exchanger458, and seat back fluid coils416and seat bottom fluid coils418for each seat410that connect between the corresponding coils inlet and outlet lines420,422. The secondary loop460may be located partially in the engine compartment454and partially in a passenger compartment468of the vehicle456.

Each seat410may also have a seat shut-off valve470for selectively blocking the flow of coolant into the coils416,418for that particular seat410. Accordingly, seats where no one is sitting will not be cooled. In addition, an extra valve and coolant line (not shown) may be added for each seat to allow the additional flexibility of controlling seat back cooling separate from seat bottom cooling (similar to that shown inFIG. 5). Also, each seat may have a seat fan415for facilitating the cooling effect for the seat occupants.