Thermoelectric device

A thermoelectric system includes a pair of substrates, a plurality of semiconductor elements, and first, second, and third terminals. The semiconductor elements are positioned between the opposing faces of the substrates, and the semiconductor elements include at least two groups of dissimilar semiconductor elements. The semiconductor elements are electrically coupled in series by conductor elements arranged so the two groups of dissimilar semiconductor elements are connected in an alternating pattern. The first, second and third terminals are connected to the conductor elements with the third terminal positioned between the first and second terminals. The electrically coupled semiconductor elements include first nodes and second nodes. The first and second nodes emit or absorb heat according to electric current flowing through the semiconductor elements, and impedance of the thermoelectric system is controlled by switching the switch.

BACKGROUND OF THE INVENTION

1. Field of the Inventions

The present application relates generally to thermoelectric devices, and more specifically, to thermoelectric devices configured for use in climate control systems for seating assemblies and the like.

2. Description of the Related Art

A Peltier circuit is a type of thermoelectric device that comprises two sides, each of which is either heated or cooled when current is delivered through the circuit. For example, when voltage is applied in a first direction through the thermoelectric device, one side generally generates heat while the opposite side absorbs heat. The thermoelectric device can be configured so that switching the polarity of the circuit can create the opposite effect. Typically, thermoelectric devices comprise a closed circuit that includes dissimilar materials. As a DC voltage is applied across the closed circuit, a temperature change is generated at the junction of the dissimilar materials. Thus, depending on the direction that electrical current flows through the thermoelectric device, heat is either emitted or absorbed. Thermoelectric devices can include several such junctions connected electrically in series. The junctions can be sandwiched between two ceramic plates that generally form the cold side and the hot side of the device. The cold side and hot side can be thermally coupled to one or more heat transfer devices (e.g., fins) that help heat the heat transfer with a volume of air or other fluid.

A vehicle ventilation system that includes such a thermoelectric device to selectively heat and/or cool a seating assembly is disclosed in U.S. patent application Ser. No. 11/047,077, filed on Jan. 31, 2005 and published as U.S. Patent Publication No. 2006/0130490. Thus, air or other fluid can be passed through or near the cold and/or hot side of a thermoelectric device (e.g., Peltier circuit) to selectively heat and/or cool the air or other fluid. The thermally conditioned air or other fluid can then be directed to one or more portions of the vehicle seat (e.g., seat back portion, seat bottom portion, neck area, etc.). Such arrangements can be particularly advantageous because thermoelectric devices are typically compact and simple.

SUMMARY

A thermoelectric system according a first embodiment of the invention comprises a pair of substrates, a plurality of semiconductor elements, and first, second, and third terminals. Each of the pair of opposing substrates has a peripheral edge and a face that generally opposes a face of the other opposing substrate. In some embodiments, the plurality of semiconductor elements are positioned between the opposing faces of the opposing substrates. In other embodiments, the plurality of semiconductor elements comprises at least two groups of dissimilar semiconductor elements. The plurality of semiconductor elements are electrically coupled in series by conductor elements arranged so the two groups of dissimilar semiconductor elements are connected in an alternating pattern.

In other arrangements, the first, second and third terminals are connected to the conductor elements with the third terminal being positioned between the first and second terminals along the circuit created by the plurality of semiconductor elements electrically coupled in series by conductor elements, and the third terminal comprises a switch. In some embodiments, the electrically coupled semiconductor elements comprise a plurality of first nodes and a plurality of second nodes. The first and second nodes emit or absorb heat according to electric current flowing through the semiconductor elements, and impedance of the thermoelectric system is controlled by switching the switch provided in the third terminal.

A thermoelectric system according to a second embodiment of the present invention comprises first and second couples of and second dissimilar conductive elements, a first terminal, a second terminal and a third terminal. The first and second dissimilar conductive elements of the first couple are connected to each other at a first common node, and the first couple comprises a first end and a second end. In some embodiments, the first and second dissimilar conductive elements of the second couple are connected to each other at a second node, and the second couple comprises a first end and a second end. The first end of the second couple is connected to the second end of the first couple at a second node. In one embodiment, the first terminal is connected to the first end of the first couple, the second terminal to the second end of the second couple, and the third terminal to the second node through a switch. The switch controls the impedance of the thermoelectric system by switching electric current through the third terminal. The switching of the switch may be associated with flowing direction of the electric current through the thermoelectric system.

In some embodiments, the first terminal may be connected to a first voltage, and the second terminal to a second voltage. The switch may be open such that electric current flows through the first and second couples of first and second dissimilar conductive elements. The first terminal may be connected to a first voltage, and the second terminal to a second voltage. The third terminal may be connected to the second voltage, and the switch may be closed such that electric current flows only through the first couple of first and second dissimilar conductive elements.

A thermoelectric system according to another embodiment of the present invention comprises first and second dissimilar conductive elements, first and second terminals, and a third terminal. The first dissimilar conductive element has a first end and a second end. The second dissimilar conductive element has a first end and a second end, and the first end of the second dissimilar conductive element is connected to the second end of the first dissimilar conductive element. In some embodiments, the first terminal is connected to the first end of the first dissimilar conductive element. And the second terminal is connected to the second end of the second dissimilar conductive element at a first node. Further, the third terminal is connected to a contact point between the first end of the first dissimilar conductive element and the first node through a switch.

In some embodiments, the switch controls impedance of the thermoelectric system by switching electric current through the third terminal. The switch may comprise a slidable leg connected to the contact point between the first end of the first dissimilar conductive element and the first node. In one embodiment, the switch comprises multiple taps connected to a plurality of contact points between the first end of the first dissimilar conductive element and the first node, and the switch closes one of the multiple taps when activated. In other embodiments, the switch is configured to select one of the multiple taps, and electric current through the first dissimilar conductive element is controlled by selecting of one of the multiple taps.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The thermoelectric devices disclosed herein and the various systems and features associated with them are described in the context of a climate control system for a seating assembly (e.g., automobile seat, bed, sofa, etc.) because they have particular utility in this context. However, the various embodiments, discussed and/or illustrated herein can be used in other contexts as well, such as, for example, but without limitation, other heating and/or cooling devices or systems.

With reference to the schematic ofFIG. 1, a thermoelectric device1can include a pair of terminals T1, T2that are located at opposite ends. In some or all of the embodiments disclosed herein, the thermoelectric device1comprises a Peltier circuit. However, the thermoelectric device1can comprise a different type of electrical circuit or configuration. Thus, the features and benefits described herein can be applied to any type of electrical arrangement that is used to selectively heat and/or cool a volume of air or other fluid. In the embodiment illustrated inFIG. 1, a DC voltage may be applied across the thermoelectric device1between the end terminals T1, T2. As described in greater detail herein, the cooling or heating effect of the thermoelectric device1can be selectively reversed by switching the polarity of the applied voltage at the terminals T1, T2.

As illustrated inFIG. 1, the thermoelectric device1can include a plurality of dissimilar conductive elements2,4that are arranged in series. Pairs of conductive elements2,4can be coupled together by a series of opposing conductor tabs8, which in turn, can be situated between a pair of opposing substrates (seeFIG. 8). Each substrate can be thermally coupled to fins or other heat transfer members (not shown) through a thermal conductive element.

In some arrangements, the thermoelectric device1is configured to be operated at a fixed voltage, such as, for example, the voltage of a battery to which it is electrically connected (e.g., approximately 13.5V if a typical automotive battery is utilized). The impedance or other electrical characteristics of the thermoelectric device1can be selected to produce the optimal cooling affect at a specific voltage. However, in fixed voltage systems, the chosen impedance is typically not optimal when the direction of the electrical current through the thermoelectric device1is reversed (e.g., to produce heat).

FIG. 2illustrates another embodiment of a thermoelectric device10that includes more than two electrical terminals T1, T2, T3. As described herein, such a configuration can permit for multiple levels of heating and/or cooling. InFIG. 2, the thermoelectric device10comprises a total of three terminals T1, T2, T3. Two of the terminals T1, T2are end terminals generally located at opposite ends of the circuit. The third terminal T3is an intermediate terminal located between the end terminals T1, T2.

In some embodiments, the operational voltage to the third terminal T3can be controlled by a hard wire contact, by an electronic switch16and/or some other method or device. A thermoelectric device10comprising one or more intermediate terminals T3can be used to selectively energize one or more desired portions of the circuit. Thus, unlike conventional two terminal thermoelectric devices (FIG. 1), such a modified thermoelectric device10can be configured to vary the heating and/or cooling effect when the amount of electrical current being delivered to the device10is generally constant. It will be appreciated that the position of the third terminal T3(or any additional intermediate terminals) can be varied as desired or required by a particular application or use. For example, the intermediate terminal T2can be located approximately halfway between the end terminals T1, T2. In other embodiments, the intermediate terminal T3can be located closer to one of the end terminals T1, T2.

With continued reference toFIG. 2, the electronic switch16can be a semiconductor switch, such as, for example, an integrated field-effect transistor (FET) switch or the like. Thus, as discussed, the switch16can be used to vary the impedance through the thermoelectric device10. For example, the impedance of the device10can be increased when a cooling effect is desired (e.g., the voltage is directed between the end terminals T1, T2) or decreased when a heating effect is desired (e.g., the voltage is directed between an end terminal T1, T2and an intermediate terminal T3). Thus, depending on the desired heating and/or cooling effect, electrical current can be delivered through only a portion of the thermoelectric device10.

With further reference toFIG. 2, a thermoelectric device10can comprise a first thermoelectric material12and a second thermoelectric material14, both of which are connected in series by a plurality of conductor elements18. As discussed, the device10can further comprise a first terminal T1at one end of the circuit, a second terminal T2at another end of the circuit and a third terminal T3positioned along an intermediate location generally between the first and second terminals T1, T2. In some embodiments, the first terminal T1is connected to a first voltage and the second terminal T2is connected to a second voltage. Further, the third terminal T3can be connected to the second voltage through a switch16(e.g., hard wire contact, electronic switch16, etc.).

Therefore, when the device10operates in a first mode (e.g., cooling), the switch16can be opened such that the difference between the first and second voltages is applied between the first and second terminals T1, T2(e.g., the end terminals). Accordingly, electrical current can flow through the entire or substantially the entire circuit (e.g., through the first and second thermoelectric materials12,14in series). Alternatively, when the device10operates in a second mode (e.g., heating), the switch16can be closed such that electrical current is applied through only a portion of the circuit (e.g., between the second and third terminals T2, T3). This can effectively reduce the impedance of the device10and create a different level of heating and/or cooling for a particular fixed voltage, as desired or required by a particular application or use.

With reference toFIG. 3, the switching of the intermediate terminal T3can be accomplished using a semi-conductor switch26or other similar device. In addition, as illustrated inFIG. 4, the selective switching of the intermediate terminal T3can be accomplished through a hard wire tap36. In other embodiments, a semiconductor switch can be incorporated into the thermoelectric materials of a device. In such arrangements, the need for a high current carrying wire could be eliminated.

It should be appreciated that the direction of the electrical current through any of the devices described and/or illustrated herein can be reversed to create a different heating and/or cooling effect, as desired or required. Thus, a thermoelectric device can be sized, designed and otherwise configured for a particular heating effect at a specific fixed voltage. When the electrical current is reversed to create a cooling effect, the thermoelectric device can comprise one or more intermediate terminals to selectively direct the current through only a portion of the circuit. Consequently, for a specific voltage, both a desired heating and cooling effect can be attained using the same thermoelectric device.

As discussed, thermoelectric devices that comprise one or more intermediate terminals can be sized, designed and otherwise configured to create a generally optimized cooling and/or heating effect at a specific voltage (e.g., the voltage provided by a car battery or other DC power source). Without an intermediate terminal, it may be difficult to create a desired opposite thermal conditioning effect (e.g., heating and/or cooling) when the current is reversed. This is because in fixed voltage systems the impedance used to create a desired thermal conditioning effect in a first thermal conditioning mode (e.g., cooling) is unlikely to create a desired opposite thermal conditioning effect in a second mode (e.g., heating). Therefore, the use of intermediate terminals and switches or other current routing devices to selectively modify the impedance through the device to create a desired heating and/or cooling effect.

In some embodiments, a power system for an automobile or other vehicle typically includes a battery that provides approximately 13.5 volts when the alternator is properly operating. In certain arrangements, two circuits (e.g., the circuits disclosed inFIG. 1) can be connected in series to effectively provide about half of the battery's voltage across these circuits. A thermoelectric device can be configured to provide optimum or close to optimum cooling at a specific voltage (e.g., the voltage supplied by an automobile battery). However, this may impact the amount of heating that could be obtained through the circuit when the electrical current is reversed. Thus, using a thermoelectric device that includes an intermediate terminal, as illustrated and discussed herein, the circuit can be designed to provide a desired cooling and/or heating effect at the full voltage of the battery without sacrificing performance when operating in the opposite thermal conditioning mode (e.g., heating and/or cooling). Such embodiments can reduce the need to place the circuits in series, resulting in less complicated control modules. In addition, optimal or near optimal cooling and/or heating can be achieved using the same substrate at a particular voltage.

Schematic circuit diagrams of different embodiments of a thermoelectric device50A,50B,50C comprising an intermediate terminal56A,56B,56C are illustrated inFIGS. 5A-5C. InFIG. 5A, the depicted thermoelectric device50A comprises two end terminals52A,54A and one intermediate terminal56A. In the illustrated schematic, the intermediate terminal56A is located approximately halfway between the two end terminals52A,54A. However, in other embodiments, the intermediate terminal56A can be located closer to one of the two end terminals52A,54A, as desired or required by a particular application.

As discussed, in order to energize the thermoelectric device50A, a current can be supplied between two terminals. InFIG. 50A, the electrical current is directed between the two end terminals52A,54A in the direction generally indicated by arrow58A (e.g., from52A to54A). Consequently, under this operational scheme, electrical current is not permitted in the direction of the intermediate terminal56A. In one embodiment, the flow of electrical current in the direction of arrow58A creates a cooling effect along a first side of the thermoelectric device50A.

When the direction of electrical current is reversed, as schematically illustrated inFIG. 5B(e.g., from one end terminal54B towards52B in a direction generally represented by arrow58B), a heating effect can be created along the first side of the thermoelectric device50B.

As discussed in greater detail herein, electrical current can be routed from an end terminal52C,54C to and/or from an intermediate terminal56C. For example, in the embodiment illustrated inFIG. 5C, electrical current can be directed from end terminal54C to intermediate terminal56C in a direction generally represented by arrow58C. This can enable a user to direct electrical current through only a portion of the thermoelectric device50C. Consequently, the extent to which the thermoelectric device50C produces a heating and/or cooling effect can be selectively controlled. For example, if the current delivered to the end terminals54B,54B is identical and if the thermoelectric devices50B,50C are similarly configured, the heating effect created along the first side of the thermoelectric device50C illustrated inFIG. 5Cwill be less than that created along the first side of the device50B ofFIG. 5B. Similarly, if current is directed from the end terminal52A to the intermediate terminal56A inFIG. 5A, the cooling effect along the first side of the thermoelectric device50A can be reduced.

InFIG. 6A, the illustrated thermoelectric device includes an intermediate terminal66A that is located closer to one of the end terminals64A. Such designs and configurations can be used to selectively control the level of heating and/or cooling occurring at or near a thermoelectric device. InFIG. 6A, electrical current is routed from one end terminal62A to the intermediate terminal66A in a direction generally represented by arrow68A. Thus, the level of heating and/or cooling created by the thermoelectric device60A can be greater than the level of heating and/or cooling created by routing current from the opposite end terminal64A to the intermediate terminal66A.

FIG. 6Bschematically illustrates an embodiment of a thermoelectric device60B that comprises two intermediate terminals65B,66B. As with other embodiments discussed and illustrated herein, the intermediate terminals65B,66B can be located at any position along the length of the thermoelectric device60B. Further, a thermoelectric device60B can include more or fewer intermediate terminals65B,66B as desired or required by a particular application or use.

As discussed, electrical current can be delivered, in any direction, between two terminals62B,64B,65B,66B. For example, current can be directed from any end terminal62B,64B to another end terminal64B,62B or from any end terminal62B,64B to an intermediate terminal65B,66B. Likewise, current can be directed from any intermediate terminal65B,66B to any end terminal62B,64B or from any intermediate terminal65B,66B to any other intermediate terminal66B,65B.

For example, as illustrated inFIG. 6B, under one operational scheme, current can be directed from one end terminal62B to one of the intermediate terminals65B in a direction generally represented by arrow67B. Likewise, under a different operational scheme, current can be directed from the other end terminal64B to another intermediate terminal66B in a direction generally represented by arrow68B. As discussed, under other operation schemes, the thermoelectric device60B can be configured to deliver electrical current between any two electrical terminals62B,64B,65B,66B, regardless of whether they are end terminals or intermediate terminals.

FIGS. 7A and 7Billustrate embodiments of circuit diagrams in which electrical current can be simultaneously delivered through two different portions of a thermoelectric device70A,70B. For example, inFIG. 7A, current is routed from one end terminal72A to an intermediate terminal76A in a direction generally represented by arrow78A to create a heating or cooling effect along a first side of the device70A. At the same time, current is routed from one end terminal74A to the same intermediate terminal76A in a direction generally represented by arrow79A to create the opposite thermal effect along a first side of the device70A. Therefore, under such an operational scheme, a portion of the thermoelectric device70A can be heated while another portion can be cooled. As illustrated inFIG. 7B, when the electrical current is reversed, the cooled and heated portions of the thermoelectric device70B can also be advantageously reversed.

FIGS. 8-11illustrate one embodiment of a thermoelectric device110that can be configured to include one or more intermediate electrical terminals as disclosed herein.FIG. 8illustrates an exploded view of one embodiment of a thermoelectric device110with its various components separated for ease of inspection.FIG. 9illustrates a side perspective view of the assembled thermoelectric device110. In addition,FIG. 10illustrates a side view of the thermoelectric device110with portions removed. Further,FIG. 11illustrates an enlarged view of a portion of the thermoelectric device110depicted inFIG. 10.

With initial reference toFIGS. 8 and 9, the thermoelectric device110can include a plurality of dissimilar conductive elements122,124. As is discussed in greater detail herein, pairs of dissimilar conductive elements122,124can be coupled together by a plurality of opposing conductor tabs128. In some arrangements, such conductor tabs128are generally disposed between a pair of opposing substrates132. In the illustrated embodiment, each substrate32is thermally coupled to one or more heat transfer members138(e.g., fins) through a thermal conductive element134. A temperature sensor150can be positioned between the opposing substrates132. In addition, a seal160can be provided between the opposing substrates132to protect the sensor150and the elements between the substrates132.

FIGS. 10 and 11illustrate side views of the thermoelectric device110with the seal160omitted to facilitate inspection of the conductive elements122,124,128that are generally located between the substrates132. In one embodiment, the thermoelectric device110comprises alternating N-type semiconductor elements122and P-type semiconductor elements124. The N-type semiconductor elements122and P-type semiconductor elements124can comprise bismuth-tellurium alloy (Bi2Te3), other doped or non-doped metals and/or any other materials. The end of each of the N-type semiconductor elements122and P-type semiconductor elements124can be coated with a diffusion barrier (not shown). The diffusion barrier can advantageously inhibit the flow of electrons out of the semiconductor elements122,124. Such a diffusion barrier can comprise any of a number of materials, such as, for example, nickel, a titanium/tungsten alloy, molybdenum and/or the like.

As illustrated in the embodiment ofFIG. 10, pairs of dissimilar conductive elements122,124can be coupled at their tops and bottoms using conductor tabs128. In some arrangements, conductive elements122,124of the same type are not disposed on the same tab128. For example, each conductor tab128can be coupled to only one N-type semiconductor element122and only one P-type semiconductor elements124. In addition, the upper and lower conductor tabs128can be configured so that the semiconductor elements122,124are disposed in an alternating series. In this manner, the semiconductor elements122,124are electrically connected in series with each other. However, with respect to thermal energy, the elements122,124include a parallel orientation relative to each other.

With continued reference toFIG. 10, a first N-type semiconductor element122can be coupled at its top to a first conductor tab128. Such a conductor tab128can also be coupled to a first the P-type semiconductor element124to the right of the first N-type semiconductor element122. At the bottom of the first N-type semiconductor element122, a second conductor tab128can be coupled to the first N-type semiconductor element122and can be coupled to a second P-type semiconductor element124to be disposed to the left of the first N-type thermoelectric element122. The thermoelectric device can be configured such that all the semiconductor elements122,124are connected in series with each other. It should be appreciated that the conductor tabs128can comprise a plurality of discrete elements coupled to the substrate132or an intermediate member. In modified embodiments, the tabs128can be formed by tracing or otherwise forming a layer of conductive material on the substrate and/or an intermediate element.

As illustrated inFIG. 10, a sensor150can be disposed on either substrate132between the semiconductor elements122,124. In other arrangements, one or more sensors150can be positioned at any other location of the thermoelectric device110. The sensor150can be adapted to measure a temperature of the device110, the air or other fluid being thermally conditioned by the device110and/or the like. It will be appreciated that the device110can comprise other types of sensors, either in addition to or in lieu of a temperature sensor.

As discussed, heat transfer assemblies138(e.g., fins) can be positioned on the top and/or bottom sides of the thermoelectric device110. According to some embodiments, the thermoelectric device110is configured to operate without the heat transfer assemblies138. However, the presence of such assemblies138can increase the efficiency of heat transfer from the thermoelectric device110to the air or other fluid passing near the thermoelectric device110.

With continued reference toFIGS. 10 and 11, an electrically-conducting solder (not shown) can be used to mount the N-type semiconductor elements122and P-type semiconductor elements124to the conductor tabs128. In one embodiment, the conducting solder can comprise one or more compounds of tin and antimony, other metals or non-metals and/or any other materials. For example, the solder can include an alloy comprising bismuth and tin. Other methods of affixing the semiconductor elements122,124to the conductor tabs128can be used, provided an electrical connection is permitted between the semiconductor elements122,124and the conductor tabs128. In some embodiments, the conductor tabs128are mounted to the substrate132via an adhesive or other material.

The substrates132can be configured to provide electrical insulation while simultaneously providing for heat conduction. In one embodiment, the substrates132comprise a ceramic material, such as, for example, alumina (ceramic), silicon and/or the like. However, various other types of materials, such as, for example, epoxy, may be used. The substrates132can be configured to be sufficiently rigid in order to maintain the shape of the thermoelectric device110. In other embodiments, flexible substrates can be used. When flexible substrates are used, a thermoelectric device can be constructed in various shapes and may have the ability to bend from one shape to another. As discussed, the substrates132can act an electrical insulator. The typical thickness for a substrate132can be between 50 and 500 micrometers. However, in other embodiments, the thickness of the substrate132can be less than 50 micrometer or greater than 500 micrometers, as desired or required. In some embodiments, the substrates132can be sufficiently large to completely cover the semiconductor elements122,124and the conductor tabs128. The conductor tabs128can be coupled to the electrically-insulating substrate132through solder, epoxy and/or any other mounting mechanism, device or method.

With continued reference toFIGS. 10 and 11, a heat transfer layer134can be disposed between the substrate132and the heat transfer member138. Accordingly, the heat transfer layer134can be disposed on the outside of each of the substrates132. In one embodiment, the heat transfer layer134comprises a plate composed of copper and/or other materials that have a relatively high thermal conductivity. In some arrangements, the thickness of the heat transfer layer134can be between 10 and 400 micrometers. However, the thickness of the heat transfer layer134can be different as desired or required by a particular application. The heat transfer member138can be coupled to the heat transfer layer by a layer of heat-conducting solder136. In the illustrated embodiment, the heat transfer member138comprises a material of high thermal conductivity (e.g., copper) that is generally shaped into a plurality of fins. Other materials or shapes can also be used, such as copper alloys or circular members. Additionally, the heat transfer between the heat transfer member138and the surrounding environment can be enhanced by providing a fluid transfer device (e.g., a fan) to move fluid (e.g., air) over and/or through the heat transfer member138.

When a current is passed through the N-type semiconductor elements122in series with the P-type semiconductor elements124, one junction128on one side of the semiconductor elements122,124is heated and a junction128on the other side of the thermoelectric elements122,124is cooled. That is, when a voltage is applied in one direction in series through the semiconductor elements122,124, alternating junctions128of the N-type semiconductor elements122and P-type semiconductor elements124will heat and cool respectively. In the embodiment depicted inFIG. 10, the junctions128of the semiconductor elements122,124alternate along the top and bottom of the device110. Thus, when a voltage is applied in one direction through the semiconductor elements122,124, the top of the thermoelectric device110heats and the bottom of the thermoelectric device110cools. When the current direction is reversed, the top of the thermoelectric device110is cooled and the bottom is heated. Current can be applied to the device110through electrical connectors140, which can be electrically coupled one of the junctions128.

The thermoelectric device110illustrated and described herein can comprise one or more intermediate electrical terminals as discussed with reference toFIGS. 1-7B. In addition, the device110can include one or more switches or other components, as desired or required for the proper operation of the device110.

As discussed, a sensor150can be disposed between the semiconductor elements122,124. The sensor150can be configured to determine any of a number of states of operation of the thermoelectric device110. For example, the sensor150can comprise a temperature sensor, such as a thermistor. In some embodiments, a thermistor with an internal resistance of about 1000Ω can be used. Sensors having other resistances and/or completely different types of sensors that detect different operating states of the device110can also be used (e.g., thermocouples, resistance thermometers, etc.). In some arrangements, the sensor150can determine the temperature of the thermoelectric device110at a point located among the semiconductor elements122,124. The sensor150can be disposed on a conductor tab128(e.g., element152) generally between an N-type semiconductor element122and a P-type semiconductor element124. Alternatively, the sensor150can be located between any two conductor elements122,124while mounted or placed on the substrate132. In a modified embodiment, the sensor150can be disposed between a semiconductor element122,124and the edge of the substrate132.

As illustrated inFIG. 10, the electrical connectors140can form the end terminals T1and T2as described herein with reference toFIGS. 1-7B. To provide one or more intermediate terminals in accordance with some of the embodiments disclosed herein, one or more connectors can be provided between the first and second terminals T1, T2.

InFIG. 12, a climate control system199for a seat assembly200is shown in combination with a pair of thermoelectric devices210a,210b. Such thermoelectric devices210a,210bcan be arranged and configured as described above. For example, in some embodiments, one or more of the thermoelectric devices210a,210bcomprise an intermediate terminal to selectively direct electrical current through only a portion of the respective circuit. In some embodiments, the seat assembly200is similar to a standard automotive or other vehicle seat. However, it should be appreciated that certain features and aspects of the climate control system199and seat assembly200disclosed herein can also be used in a variety of other applications and environments. For example, certain features and aspects of the system199and assembly200may be adapted for use in other vehicles, such as, for example, airplane, trains, boats and the like. In addition, the features, aspects and other details of the system199and assembly200can be applied to other types of seating assemblies, such as, for example, wheelchairs, beds, sofas, office chairs and other types of chairs, theater seats and/or the like.

With continued reference toFIG. 12, the seat assembly200can comprise a seat portion202and a back portion204. The seat portion202and back portion204can each comprise a cushion206a,206band a plurality of channels208a,208bdisposed within and/or extending through the cushions206a,206b. Each of the channels208a,208bcan be placed in fluid communication with the climate control system199through a conduit210a,210b. The conduits210a,210b, in turn, can be in fluid communication with separate climate control devices212a,212b. In the illustrated embodiment, the channels208aassociated with the seat portion202are in communication with a different climate control device212athan the channels208bin the back portion204. However, in other embodiments, a single climate control device can be in fluid communication with the channels208a,208bof both the seat portion202and back portion204. In yet other embodiments, multiple climate control devices can be associated with either the seat portion202and/or the back portion204. In some embodiments, the channels208a,208band/or conduits210a,210bcan include resistive heating elements (not shown).

In the illustrated embodiment, the climate control devices212a,212bcan each comprise a thermoelectric device210a,210b, which can be configured as described above (e.g., having one or more intermediate electrical terminals), and a fluid transfer device230a,230b. The fluid transfer device230a,230bcan comprise a radial or axial fan, or any other device for transferring a fluid. Each thermoelectric device210a,210bcan be disposed between a fluid transfer device230a,230band the respective conduit210a,210b. As discussed, the thermoelectric device210a,210bcan be configured to selectively heat or cool a fluid (e.g., air) delivered by the fluid transfer device230a,230bto the seat portion202and/or back portion204. The fluid transfer device230a,230bcan be configured to transfer air or other fluid to the channels208a,208bthat is drawn past only one side of the thermoelectric device210a,210b. Accordingly, the climate control devices212a,212bcan be configured to selectively supply heated or cooled air222a,222bthrough the plurality of conduits210a,210bto the seat assembly200. The fluid transfer device230a,230bcan also be used to withdraw air through the conduits210a,210b. In yet other arrangements, heated and/or cooled air or other fluid can be delivered to any other portion of the seat assembly200(e.g., neck rest area), either in lieu of or in addition to the plurality of conduits210a,210b.

In the embodiment illustrated inFIG. 12, each of the thermoelectric devices210a,210bincludes a pair of heat transfer members238as described herein. The heat transfer members238form a waste heat exchanger and a generally opposing main heat exchanger, which can be thermally exposed to the air or other fluid transferred by the fluid transfer device230a,230b. Depending upon the mode of operation, heat can be transferred to the air or other fluid through the main heat exchanger or withdrawn from the air or other fluid through the main heat exchanger.

The climate control devices212a,212bcan be controlled and operatively connected by an electronic control device214a,214b. The electronic control devices214a,214bcan receive signals from a plurality of input sources216,218,220. In the illustrated embodiment, three input sources are shown, but more or fewer can be used. The electronic control devices214a,214bcan be operatively connected with each other through an information connection224. The electronic control devices214a,214bcan be configured change the operating state of the climate control devices212a,212bin response to a control signal or setting. For example, the electronic control devices214a,214bcan alter the speed at which fluid is transferred by the fluid transfer devices230a,230bor the operating state of the thermoelectric devices210a,210bto heat or cool the fluid. One or more sensors150(FIGS. 8-11) disposed in the thermoelectric devices210a,210bcan impart information through one or more hardwired and/or wireless connections to the electronic control devices214a,214b. This can permit the devices214a,214bto accurately determine the operating temperature of the climate control devices212a,212b. The electronic control devices214a,214bcan adjust the operation of the climate control devices212a,212bbased at least in part on information provided by a sensor. For example, the electronic control devices214a,214bcan change the direction or strength of current in the thermoelectric devices210a,210b, change the speed of operation of the fluid transfer device230a,230b, and/or shut down the devices210a,210bif there is a malfunction.

In other embodiments, the electronic devices214a,214bcan direct the electrical current through an end terminal or an intermediate terminal to a specific end terminal or other intermediate terminal as disclosed herein. This can permit the thermoelectric devices210a,210bto provide a desired or required level of heating and/or cooling.

Various components are described as being “operatively connected” to the control unit. It should be appreciated that this is a broad term that includes physical connections (e.g., electrical wires or hard wire circuits) and non-physical connections (e.g., radio or infrared signals). It should also be appreciated that “operatively connected” includes direct connections and indirect connections (e.g., through additional intermediate device(s)).