Heat exchange – Flexible envelope or cover type
Reexamination Certificate
1997-12-18
2001-04-17
Flanigan, Allen (Department: 3743)
Heat exchange
Flexible envelope or cover type
C165SDIG119, C165S104330, C361S699000
Reexamination Certificate
active
06216771
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for fluid based transport of heat, in connection with electrical equipment, such as e.g. printed circuit boards.
DESCRIPTION OF RELATED ART
In practice, all electrical components generate heat when in operation. This is of particular interest, and usually also a source of problems, in situations and applications where many electrical components are situated close together in confined spaces. Since most components have an upper temperature limit at which they can operate reliably, removal of excess heat is of vital importance. Many solutions to this problem exist, and a separation into two types of cooling systems can be identified. One group of solutions is characterized by air-flow around the heat generating equipment. This is a common case, and usually calls for relatively large heat sinks mounted on the heat generating components. An obvious drawback of constructions of that type is that they are bulky. It is also difficult to create air-flows large enough and in the right place, in order to cool the components efficiently. Usually large fans are needed, making the constructions even more complicated and bulky.
In a second type of solution, cooling is obtained by direct or indirect thermal contact between the components and a heat transporting fluid inside a pipe or tube. Both of these kinds of fluid based solutions have disadvantages, as will be exemplified below by a few previously disclosed inventions.
The German patent DD-139513 discloses an apparatus for cooling sealed electric equipment. Flexible metal pipe coils are situated inside a housing containing electric modules. Air is forced through the pipe, and acts as a heat carrying fluid. One end of the pipe can be connected to a fan in order to increase the flow of fluid through the pipe.
A drawback of the apparatus presented in DD-139513 is that there is no direct thermal contact between the pipe and the heat generating modules. There is an air interface which makes the transport of heat ineffective.
Another cooling device is disclosed in the American patent U.S. Pat. No. 4,851,856. A rigid tube with a multitude of slots along its length is situated adjacent to heat generating electric modules. Inside the rigid tube is a flexible hose, through which hose a coolant fluid is introduced under pressure. The pressure of the fluid expands the hose outwards through the slots, creating direct contact between the walls of the hose and the heat generating modules.
A drawback of the invention disclosed in U.S. Pat. No. 4,851,856 is that it is necessary to have a rigid tube holding the flexible hose in place. Also, the locations of the slots are fixed and can not be altered unless the rigid tube is exchanged. This means that it is a complicated construction which is difficult to adjust to different configurations of heat generating modules.
A third disclosure of cooling electric equipment by fluid, can be found in U.S. Pat. No. 5,404,270. Cooling units with flexible walls are situated between electric circuitry packages. The cooling units and the packages having more or less the same physical dimensions. Pressurized fluid bring the cooling units in contact with the heat generating electric packages.
A drawback of the invention disclosed in U.S. Pat. No. 5,404,270 is that, in order to cool several electric packages, a plurality of cooling units coupled in parallel is needed. This leads to a system comprising a plurality of coupling units, which in turn means large complexity and increased probability of leaks.
SUMMARY OF THE INVENTION
The problems addressed by the present invention, as suggested by the drawbacks of the documents cited above, can be stated as follows.
A first problem is how to transfer heat in connection with electric equipment without using bulky heat sinks and fans.
Another problem is how to accomplish heat transfer means that are simple in construction and easy to install and reconfigure with respect to varying configurations of electric equipment.
Yet another problem is how to accomplish heat transfer means that are reliable with respect to leaks.
Although not explicitly mentioned in the problems, as stated above, it is obviously the case that the heat transfer methods means should also be capable of transporting heat to electric equipment (i.e. heating), as well as the more common case of transporting heat from the equipment (i.e. cooling).
The object of the present invention is hence to overcome the problems stated above. This is accomplished by arranging a flexible tube, said tube being pressurized and brought in direct thermal contact with heat generating components, through which tube a heat carrying fluid is flowing.
A method for solving the problems stated above, discloses how to arrange heat transport in connection with electric components. The components are situated on sub-units, such as e.g. printed circuit boards. The sub-units can be housed in main units, such as e.g. cabinets. A flexible tube is arranged in connection with the sub-units. The tube is connected to means capable of supplying fluid into the tube and also pressurizing the fluid. Fluid is then introduced into the tube and pressurized. By the pressure, the fluid flows through the tube and the tube wall gets in thermal contact with the electric components and heat can be transferred between the fluid and the components.
A system for heat transport is also disclosed, which system comprises electric components on sub-units. The sub-units being in contact with a flexible tube through which tube a pressurized fluid is flowing.
An advantage of the invention is that it facilitates both the installation and the re-configuration. The tube is in one single piece and it is flat and flexible until it is pressurized. When de-pressurized it is easy to remove from the system without need to remove the electric equipment.
Another advantage is that, since the tube is flexible and can be of almost arbitrary length, it is easy to configure a flexible system, where modules of electric equipment can be added and removed without having to change tube. One tube can be used for different sized units comprising the electric equipment.
Yet another advantage is that, by having a tube in one single piece, the risk of leaks is minimized. This is due to the fact that there are no couplings inside the units where the tube is arranged.
Yet another advantage is that smaller cabinets can be used, as compared to systems that are cooled by air freely streaming in the cabinet. There is no need for large heat sinks and fans.
Yet another advantage by having a tube containing the heat carrying fluid, is that the disadvantage of having potentially dirty air flowing around electric components, which may harm the components.
REFERENCES:
patent: 790971 (1905-05-01), Nicholls
patent: 2254406 (1941-09-01), Zarotschenzeff
patent: 3032357 (1962-05-01), Shames et al.
patent: 4020399 (1977-04-01), Suzuki et al.
patent: 4109707 (1978-08-01), Wilson et al.
patent: 4851856 (1989-07-01), Altoz
patent: 4938279 (1990-07-01), Betker
patent: 4997032 (1991-03-01), Danielson et al.
patent: 5000256 (1991-03-01), Tousignant
patent: 5006924 (1991-04-01), Frankeny et al.
patent: 5007478 (1991-04-01), Senupta
patent: 5343940 (1994-09-01), Jean
patent: 5404270 (1995-04-01), Carlstedt
patent: 5740018 (1998-04-01), Rumbut, Jr.
patent: 26 38 702B2 (1978-03-01), None
patent: 139 513 (1980-01-01), None
patent: 0 014 249A1 (1980-08-01), None
patent: 0 014 249 (1980-08-01), None
patent: 0 309 279 (1989-03-01), None
patent: 0 573 533 (1993-12-01), None
patent: 0 580 412A1 (1994-01-01), None
patent: 0 580 412 (1994-01-01), None
patent: 92/10692 (1992-09-01), None
Print of English Abstract from JP 3 60-0220954A, cited in Altoz reference, Published Nov. 1985.*
Patent Abstracts of Japan, vol. 15, No. 159, E-1059, abstract of JP A 3-30399, Feb. 8, 1991 (Matsugi).
Piled Electronics AB “The cool company”, Pile it up! Increase the speed!, 8 pages.
Gudmundsson Bjorn
Holmberg Ulf I.
Burns Doane Swecker & Mathis L.L.P.
Flanigan Allen
Telefonaktiebolaget LM Ericsson (publ)
LandOfFree
Method and apparatus for arranging heat transport does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for arranging heat transport, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for arranging heat transport will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2441739