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Timestamp: 2019-04-18 10:22:40+00:00

Document:
patent is extended or adjusted under 35 U.S.C. 154(b) by 343 days.
12/1996 Wright et al. 1/1997 Atarashi et al. 2/1997 Park et al.
11/1997 De Viilbiss et al.
2/1999 Ghoshal 5/1999 Harman 7/1999 Imaizumi et al.
(63) Continuation of application No. 09/860,725, filed on May 18, 2001, now Pat. No. 6,672,076 (60) Provisional application No. 60/267,657, filed on Feb. 9, 2001.
International Search Report for PCT/US 02/06285 dated May 11, 2002.
1/1978 Fenton et al. ................. 62/3.3 8/1981 Berthet et al.
3/1988 Schlicklin et al. 3/1988 Ralston et al.
Kim et al. McGrew Kadotani et al. Bielinski Bathelor et al.
11/2002 Ohkubo et al. 11/2002 Carr et al.
Miner, A., Majumdar, A., and U. Ghoshal, Thermo-Elec tro-Mechanical Refrigeration Based on Transient Thermo electric Effects, Applied Physics letters, vol. 75, pp.
Buist, R. and Lau, P., Theoretical Analysis of Thermoelectric Cooling Performance Enhancement Via Thermal and Elec trical Pulsing, Journal of Thermoelectricity, No. 4, 1996. Copending U.S. Application No. 09/844,818 filed on Apr.
27, 2001 (Atty No. 001A) and pending claims.
Copending U.S. Application No. 10/227,398 filed on Aug.
International Search Report for PCT/US 02/03654 dated May 20, 2002. International Search Report for PCT/US 02/03659 dated Jul.
23, 2002 (Atty No. 001CP1) and pending claims.
International Search Report for PCT/US 02/25233 dated Sep. 24, 2002. International Search Report for PCT/US 03/17834 dated Jul. 29, 2003.
18, 2001 (Atty No. 002A) and pending claims.
2001 (Atty No. 002CP1) and pending claims.
2002 (Atty No. 004A) and pending claims.
2001 (Atty No. 006A) and pending claims.
ing System (Numerical Analysis for Heating System), 16"
2002 (Atty No. 009A) and pending claims.
International Conference on Thermoelectrics (1997).
Copending U.S. Application No. 10/074,543 filed on Feb.
This Application is a continuation of application Ser. No. 09/860,725, filed May 18, 2001, now U.S. Pat. No. 6,672, 076, and is related to and claims the benefit of the filing date of prior filed U.S. Provisional Patent Application No. 60/267,657, filed Feb. 9, 2001.
4 configured to permit flow of at least one convective medium through the at least a portion of the array to provide generally Steady-state convective heat transport toward at least one side of at least a portion the thermoelectric array. The thermoelectric System may be used for cooling, heating or both cooling and heating.
Note, as a check if Z - co, B - C.
Several commercial materials have a ZTA approaching 1 over Some narrow temperature range, but ZTA is limited to unity in present commercial materials. Typical values of Zas a function of temperature are illustrated in FIG. 4. Some experimental materials exhibit ZTA=2 to 4, but these are not in production. Generally, as better materials may become commercially available, they do not obviate the benefits of the present inventions. Several configurations for thermoelectric devices are in current use in applications where benefits from other quali ties of TES outweigh their low efficiency. Examples of uses are in automobile Seat cooling Systems, portable coolers and refrigerators, liquid cooler/heater Systems for Scientific applications, the cooling of electronicS and fiber optic Sys tems and for cooling of infrared Sensing System.
a thermoelectric material of a different conductivity type from the first Set. Alternatively, the tubes may concentrically alternate between p-type thermoelectric material and n-type thermoelectric material.
S being thermoelectric elements of a Second conductivity type.
Sides exhibit a temperature gradient between them during operation. At least a portion of the thermoelectric array is configured to permit flow of at least one convective medium through the at least a portion of the array to provide generally Steady-state convective heat transport toward at least one side of at least a portion the thermoelectric array. According to this aspect of the present invention, the System has at least one control System, with at least one controller, at least one input coupled to the controller, and at least one output coupled to the controller and to the thermoelectric array. The output is advantageously controllable by the controller to modify at least one characteristic of at least a portion of the thermoelectric array. The at least one input may be at least one external Sensor, at least one Sensor internal to the thermoelectric array, or a user Selectable input, Such as a Switch or a thermostat, or any combination of these. In one embodiment, the controller operates in accordance with at least one algorithm responsive to the at least one input to control the at least one output. Preferably, the at least one characteristic impacts the convective heat transport, and the adjustment improves efficiency or power output by adjusting the characteristic. For example, the control System varies movement of at least Some of the convective medium in response to the input. In another embodiment, the control System adjusts other characteristics, Such as the current through at least Some of the thermoelectric elements. The adjustment of characteris tics other than the convection may be alone or in combina tion with adjustment of the convection. These and other aspects are described in more detail below in conjunction with the following figures.
elements. An example of Such heat transfer feature is a convective medium flow disturbing feature. Another aspect of the present invention involves a method of improving efficiency in a thermoelectric System having a plurality of thermoelectric elements forming a thermoelec tric array. The thermoelectric array has at least one first side and at least one Second Side exhibiting a temperature gra dient between them during operation of the thermoelectric array. The method involves actively convecting thermal power through at least a portion of the array in a generally Steady-state manner. Generally, the Step of convecting ther mal power involves flowing at least one convective medium through at least a portion of the thermoelectric array. The convective medium may be fluid, Solid or a combination of fluid and solid. The method may be used for cooling, for heating or for both cooling and heating applications. In one advantageous embodiment, the Step of flowing involves flowing at least Some of the convective medium through at least Some of the thermoelectric elements. For example, the thermoelectric elements are constructed to be permeable or porous. The thermoelectric elements may also be hollow, Such as having a tubular or honeycomb configu ration.
hollow form forming the at least Some thermoelectric ele mentS.
the need for a fluid Source or fluid on that side.
FIG. 17 depicts an existing device used to both heat and cool that can be improved in its efficiency by convective heat transfer in accordance with the present invention; and FIG. 18 depicts an embodiment with convective heat transfer of an improvement of the device of FIG. 17 in accordance with the present invention. FIG. 19 illustrates a control system for use with thermo electric Systems of the present invention.
the IR heating within the TE elements.
Ko)(c) == x 19.- e.
energy balance requirement that CpMAT (the power required to heat or cool the fluid) cannot exceed q, (the heat generated by the TE) or q (the heat absorbed by the TE).
Typically, this restricts 8 to less than 5. Actual improvement in COP for allowable values for 8 ranges up to about 100%. Similarly, q improves by up to about 50%.
and circuitry 705 on the cold side substrate 703. Similarly, x=L is interface between the TE elements 704 and circuitry 705 on the hot side substrate 702. The temperature 711 is TA at X=0 and T at X=L. FIG. 8A depicts one embodiment of a TE system 820 in accordance with the present invention. This TE system 820 is similar to the TE system 700 but has convective heat transport. The TE system 820 has many parts corresponding to those of the TE system 700 shown in FIG. 7A which are labeled with the same reference numerals.
heating transported to the cold end by IR heating.
in the resistive heating term from convection. The net result is that under many important practical operating conditions, cooling efficiency increases. Calculations for Specific TE Systems are required to determine conditions that exhibit gain when utilizing convective transport. The basic concept of improvement in efficiency by Steady State convective heat transport through the array is explained using FIGS. 7 and 8. FIG. 7A depicts a conventional TE system 700 without convective heat transport. ATE element array 701 is constructed with a hot side substrate 702 and a cool side Substrate 703 sandwiching a plurality of TE elements 704, electrically connected in series by circuitry 705. A power source 710 is applied across the TE array 701.
912 are also contained within heat exchangers 908 that are connected to two finned tube arrays which are electrically insulated from one another. There are two Sets of channels 910 in the cool side heat Sink 906.
ductance of the TE element 902. In one embodiment, the sleeves 924 are formed of Solid thermoelectric material.
along the direction of fluid flow (e.g., as indicated by the line 1008).
rials are described by A. F. Loffe, in Semiconductor Thermal Elements, and Thermoelectric Cooling, InfoSearch, London, 1957. Another example is P-type Bismuth Telluride slurried in mercury and N-type Bismuth Telluride slurried in mer cury.
1612 convects heat from an external heat sink to the cold side of the TE elements 1605.
(convective medium) 1307 to flow through the array.
1710 is heated. The housing 1708 is constructed so as to minimize both thermal losses to the environment and heat transfer between the main and waste Sides.
causes adjustments to be made to the System in accordance with the Sensor inputs. When System complexity warrants it, an algorithm may be employed within the control circuitry or its Software.
The control circuitry 1901 can provide electrical outputs to a variety of devices that can adjust for example, power to the TE elements, resistance of TE elements, or flow of fluids.
through the thermoelectric elements. In other words, a convective medium may flow from a point between the hotter Side and the colder Side along the thermoelectric elements toward both the hotter side and the cooler side.
Similarly, in the embodiment of FIG. 18, with the convective material entering from between the hotter Side and the colder side, flow could be toward one or the other sides.
18 To optimize overall performance operation in both cool ing and heating, design tradeoffs are made and it is advan tageous to allow material movement or fluid rates to vary, along with current, and independently, with the proportions of flow to the cold and hot Sides.
The concepts and designs that were discussed in the context of heating apply to cooling as well. In many designs the same device can be used in both the cooling and heating mode with very little, if any, physical change to the System. For example, the modified CCS system presented in FIG. 18 could be used in both heating and cooling mode by adjusting current flow and direction and varying fan speed.
elements either individually or as groups.
side and at least one second Side exhibiting a tempera ture gradient between them during operation, wherein the at least one thermoelectric element is configured to permit flow of at least one convective medium through the at least one element to provide generally steady state convective heat transport toward at least one side of the thermoelectric element.
2. The thermoelectric system of claim 1, wherein the at least one convective medium flows through the at least one thermoelectric element.
3. The thermoelectric system of claim 2, wherein the at least one thermoelectric element is permeable. 4. The thermoelectric system of claim 3, wherein the at least one thermoelectric element is porous. 5. The thermoelectric system of claim 2, wherein the at least one thermoelectric element is tubular.
the first and the second sides toward the first side or toward the Second Side.
8. The thermoelectric system of claim 2, wherein the at least one convective medium flows generally from the first Side to the Second Side.
9. The thermoelectric system of claim 2, wherein the at least one convective medium flows generally from the Second Side to the first Side.
at least Some of the at least one convective medium and the at least one thermoelectric element.
the first side and the second side toward the first side and toward the Second Side.
13. The thermoelectric system of claim 12, wherein the at least one convective medium flows along the at least one thermoelectric element in a single general direction. 14. The thermoelectric system of claim 13, wherein the at least one convective medium flows generally from between the first side and the second side toward the first side or toward the Second Side.
Side to the Second Side.
16. The thermoelectric system of claim 12, wherein the at least one convective medium flows generally from the Second Side to the first Side.
heat transfer feature is inside the tubular thermoelectric element.
least two thermoelectric elements form concentric tubes with the convective medium flow between the concentric tubes.
medium thermoelectric material flows through the Solid tubular thermoelectric material, the combination forming the 26. The thermoelectric system of claim 1, wherein at least part of the convective medium is a fluid.
43. The method of claim 37, wherein the step of flowing comprises flowing the at least one convective medium in at least two general directions. 44. The method of claim 43, wherein the step of flowing comprises flowing the at least one convective medium generally from between the first Side and the Second Side toward the first side and toward the second side.
Solid thermoelectric material is tubular, and the convective thermoelectric element.
41. The method of claim 37, wherein the step of flowing comprises flowing the at least one convective medium generally from the first Side to the Second Side. 42. The method of claim 37, wherein the step of flowing comprises flowing the at least one convective medium generally from between the first Side and the Second Side toward the first side or toward the second side.
electric element having a similar shape. 48. The method of claim 37, wherein at least a portion of the convective medium is a fluid.
US 6,948,321 B2 21 49. The method of claim 48, wherein at least a portion of the convective medium is air.
50. The method of claim 37, wherein at least a portion of the convective medium is a Solid.
the convective medium is a mixture of fluid and Solid.
System is used for cooling.
System is used for heating.
acteristic of Said thermoelectric element.
59. The thermoelectric system of claim 55, wherein the at least one input comprises at least one external Sensor. 60. The thermoelectric system of claim 55, wherein the at least one input comprises at least one Sensor internal to the at least one thermoelectric element.
least one user Selectable input. 62. The thermoelectric system of claim 55, wherein the at least one input is a user Selectable input. 63. The thermoelectric system of claim 55, wherein at least one controller operates in accordance with at least one algorithm responsive to the at least one input to control the at least one output.
..) insert --. -- (period).
Line 14, replace “Ti, with -- TA --.
Line 19, after “conductivity insert --. -- (period).
Line 16, after “claim 30 insert --, -- (comma).
Report "(12) United States Patent (10) Patent No.: US 6,948,321 B2"

References: application No. 09
 application No. 60
 Application No. 09
 Application No. 10
 Application No. 10
 Application No. 60