CA2359101A1

CA2359101A1 - Adapter kit to allow extended width wedgelock for use in a circuit card module

Info

Publication number: CA2359101A1
Application number: CA002359101A
Authority: CA
Inventors: Robert D. Habing; Thomas A. Odegard
Original assignee: Individual
Current assignee: Honeywell Inc
Priority date: 1998-12-30
Filing date: 1999-12-20
Publication date: 2000-07-13
Also published as: EP1236385A1; EP1236385B1; JP2003526199A; IL144078A0; DE69910848D1; WO2000041450A1; US6212075B1; DE69910848T2

Abstract

An adapter for commercial off-the-shelf (COTS) circuit card modules resultin g in increased cooling efficiency. COTS circuit card modules generally have at least one printed wiring board (PWB), at least one component mounted on the PWB, a heatsink or some type of heat path, a frame for supporting the cards, and a wedgelock for use with a conduction-cooled chassis. The adapter increases the cooling efficiency of such COTS modules while allowing them to remain compliant with IEEE 1101.2 Specifications. The invention is efficient in removing heat from the COTS circuit card modules as it increases the conduction contact area between the chassis cold wall and the COTS module. I n addition, the adapter allows for the use of an extended width wedgelock to increase the clamping force over the conduction contact area. The extended width wedgelock is mounted to one surface of the frame such that when installed in a conduction-cooled chassis, the opposite frame surface is forc ed against the chassis cold wall. The increased wedgelock size approximately doubles the clamping force applied. The net effect of these improvements are a reduction in the thermal resistance per inch of wedgelock length. This, in turn, reduces the module to chassis interface temperature rise. The improved thermal resistances anddecreased temperature rises boost the reliability of the COTS circuit cards, particularly in the stringent environments experienc ed in military applications.

Description

ADAPTER KIT TO ALLOW EXTENDED WIDTH WEDGELOCK FOR USE IN
A CIRCUIT CARD MODULE
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to co-pending application, filed on even date herewith, entitled "Interchangeable Stiffening Frame With Extended Width Wedgelock For Use in a Circuit Card Module."
BACKGROUND OF THE INVENTION
The present invention pertains generally to the field of computer card modules and the frames contained within the modules. More specifically, the present invention relates generally to circuit card modules having frames that can be adapted to improve the cooling properties of the modules but optionally remain compliant with Institute of Electrical and Electronics Engineers (IEEE) specifications.
Commercially-available, off the-shelf components that are included in circuit card modules are often unreliable when exposed to the high temperatures present in, for example, the military environment. This is due to the ineffectiveness of conventional methods of controlling component junction temperatures under stringent temperature conditions. Conventional cooling methods utilized in off the-shelf parts include normal convection, forced convection - such as fan cooling, liquid cooling, various forms of heat conductors or sinks, etc. - and combinations of two or more of these methods.
Numerous patents have issued to structural designs having cooling properties for use with circuit card modules. For example, U.S. Patent No. 5,280,411, issued to Dirks et al. discloses the addition of heat conducting rails to the edges of a circuit card. Meyer, IV et al., in U.S. Patent No. 5,549,155, teaches the use of a heat conductive pad and a heat pipe to disperse the unwanted heat from a computer chip. U.S. Patent Nos.
5,532,430 and 5,559,675, of Lanoe and Hsieh et al., respectively, disclose heat dissipating structures for use with circuit cards. In U.S. Patent No.
4,916,575, Van Asten discusses the use of a ribbed frame, which is structured to hold multiple cards.
Several patents, including U.S. Patent Nos. 4,558,395; 5,482,109; 5,714, 789;
and 5,625,227, disclose the use of a circulating coolant system to remove the generated heat.
However, none of these patents disclose or suggest a structure that satisfies the IEEE

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1101.2 standards (i.e., IEEE Standard for Mechanical Core Specifications for Conduction-Cooled Eurocards), which specifies convection-cooled chassis nGquiremcnts and conduction-cooled chassis reduiz~ements.
The prior art has also recognized the utility of additional force at the contact points between module stn~ctures and the computer chassis. Morriaon, U.S. Patent No.
4,994,937, and Mosey, U.S. Patent No. 5,262,5$7, teach clamping structures to achieve this goal. Buzzelli, in U.S. Pateat No. 4,$53,829, discloses a locking mechanism having a sliding block which holds the module to the hcatsink plate. As nnartioned above, none of these references appear to satisfy the IEEE standards of current interest.
to The current methods for cooling carusnercial off the-shelf circuit catds,.such as Versa Module Eurocards (VMEs), are conduction-cooled modules that operate in a conduction- , cooled chassis or a convection-cooled chassis, such as described in ZFEE
1101.2 Speci&cations. In order to oo~mply with the IEEE 1101.2 Specif rations, the cards must be mechanically compliant with both chassis types. This requires an approximately O.Ib cm 1s thick x 0.249 cm wide protrusion aloag the card edge to engage the convection-cooled chassis card guides. This protrusion is offien en extension of the printed wiring board (PWH) or machined as part of PWH. A challenge posed by the IEEE 1101.2 Specifications is that the card modules must be compatible with existing forced-air cooled chassis or racks, which do not use wedgelocks far best exchange or mcehanical mounting. Instead, the existing 2o forced-air cooled chassis use the edge of the PWB as a guide and one of the mechanicat attacl>Dnent points for the chassis. In the convection-cooled configuration, air flow over the card is used to remove component heat. In the conduction-cooled configuration, the aamponent heat is removed by cattdtxtio~n to the chassis sold wall. The heat is then rernoved fmm the chassis by external means. The protrusion reduces the efficie~acy of heat removal 2S by reducing the available conduction contact area and by reducing the size of the wedgeloek that can be used, These two effects redact the efficiency of movement ofthe heat to the cold wall of the chassis. Because of these legacy requirements, the conduction-cooled modules do not take full advantage of the area available at the cold wall of the chassis.
Accordiagly, it is an objort of the present invention to provide an adapter for 3o COTS circuit card modules resulting in improved cooling efFciency.

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It is a further object of the prescsst invention to impmve the cooling efficiency of the circuit card module by developing an adapter for existing circuit card modules which provides a more direct path for the dissipation of heat from the components of the circuit card modules.
It is still a further object of the present invention to improve the cooling efficiency of the module through the use of an extended width (larger) wedgelock. .
It is yet a fiuther object of the present invention to in4-reasc the conductioa contact eras between the frame of the circuit card module and the chassis.
to BRIEF SUMMARY OF THE INVENTION
The following siusvtu<ry of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention, and is not intended to be a foil description. A full appreciation of the various aspects of the invention can only be gained by taking the entire specification, claims, drawings, and abstract as a whole.
t5 The present invention is an adapter kit for commetxial o~ the-shelf tCOTS) circuit card z~~odule chat has increased cooling efficiency when plbced in a conduction-cooled chassis. Generally, COTS circuit card modules eompiiaes one or morn printed ;
wiring boards (PWH), at least one cornponextt mounted on the PWH, and a hoaisink that creates a heat path from the component to the chassis, and a wcdgalock for s<,~ring the , 2o module to the conduction-cooled chassis. the adapter frame of the present invention comprises an extended width.wedgelock (13), an extended width shim {IS), and alt ' extension ( 1 ~ to the existing frame ( 1 ) so that tb~e circuit card module contacts the cold G
wall of the conduction-cooled chassis (2). The present invention is compatible with the IEEE 1 I 01.2 Specifications. The present invention increases the conductian contact arcs ;
2s i7etween the chassis cold wall and the module. In accordance with the present invention, existing wedgeloeks are increased in width from approximately O.b35 crn to ' approximately 0.889 cm. In the present invention, the wedgeloek is mounted to one surface of the frame such that when installed in a conduction-cooled chassis, the opposite frame surface is forced against the chassis cold wall. The increased wedgelock size so approxinuatcly doubles the clamping fozr~a applied with respect to conventional modules. , The net effect of these improvements are a reduction in the thermal resistance rev. vv vviv~ cr-n rvn.!r.:v~.ttt_u a i ~~_ _~ : .L~J-~- 1 - 1 . 2U :48 :
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per inch of wedgclock length in the range of, for example, approximately 0.42° C!W to approxiamately 0.21° ClW. This, in tam, reduces the module to chassis interface temperature rise. The improved thcrrnral resistances and decreased temperature rises boost the reliability of the COTS circuit cards as compared to the prior art, particularly in the s stringent environments experienced in military applications.
The novel featL~.res of the present inventian will become apparent to those of skill in the art upon examination of the following detailed descripticm of the invention or can be learned by practice ofthc present invention.
to HRIEF DESCRIPTION fJF THE DRAWINGS
'ihc accompanying ftgu~s, in which like rafcrcrrce numerals refer to identical or .
functionally-similar elements throughout the separate views and which arc inco:porated in and form part of the speciEcation, feather illustrate the present invcntian and, together with the detailed description of the invention, serve to explain the principles of the present 15 invention.
FIG. 1 illustrates a cross-sectional view of a prioz art COTS circuit card module installed in a conduction-coolod chassis (i~rlly cozopliant with IEEE 1101.2 '-Specifications). ;
FIG. 2 illustrates a cross-sectional view of a new stiffening frame installed in a i 2o conduction-cooled chassis (partially compliant with IEEE 1101.2 Specifications). ;
FIG. 3 illustrates a cross-sectional view of a prior art circuit card module installed in a convection-cooled at~assis {fully compliant with IEEE l 1 Ol .2 Specifications).
FIG. 4 illustrates a cross-sectional view of can alternate embodiment of the new ' stiffening flame installed in a convection-cooled chassis (fully compliant with IEEE .
25 1101.2 Specifications).

i FIG. 5 illustrates a cross-sectional view of the alternate embodiment of the new stiffening frame installed in a conduction-cooled chassis (fully compliant with IEEE
1101.2 Specifications).
FIG. 6 illustrates a cross-sectional view of a COTS circuit card module modified 5 with an adapter to increase thermal efficiency in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The discussion of FIGS. 1 through 5 is related to a new stiffening frame (i.e., FIGS. 2, 4, and 5) that is being filed as a patent application on even date herewith with a title of "Interchangeable Stiffening Frame With Extended Width Wedgelock For Use in a Circuit Card Module" by the same inventors of the present invention. The discussion of FIGS. 1 through 5 provides a discussion of the problems experienced in the art and solutions thereto, and thus, this discussion has been retained for an understanding of the present invention. The present invention is depicted in FIG. 6 and the discussion thereof.
Referring to FIG. l, there is shown a cross-sectional view (top or side view) of a conventional circuit card module design installed in a conduction-cooled chassis 2. The module of FIG. 1 comprises two circuit cards: a mezzanine card 8 and a base card 7 although the number and type of cards can vary. A plurality of electrical components 6 (e.g., integrated circuits, high-power die-up devices, etc.) are mounted (e.g., soldered, ball grid array, etc.) on circuit cards 7 and 8, although FIG. 1 illustrates component 6 mounted on card 7 only. Component 6 generates heat during its normal operation, and two thermal paths for heat removal are provided. The first thermal path is through the lower surface of component 6 to the end of circuit card 7 to chassis cold wall 2 via metal strip S (or shim). The metal strip 5 acts both as a heatsink and as protection for the card 7 against damage when it is inserted and removed from the chassis 2. The other thermal path for component 6 (shown by the dotted arrow in FIG. 1 ), and the primary one of interest, is through the top surface of component 6 to thermally-conductive heatsink 9 to module frame 1 and to chassis cold wall 2 via card 7 and metal strip 5.
Optionally, heatsink 9 and frame 1 can be constructed from one piece of material. The heat efficiency of this thermal path is directly affected by the clamping force exerted by wedgelock 3 (i.e., the higher the pressure, the lower the thermal resistance) and the RCV. ~J()N: FPA Hii. ~k:VCIiEN a 1 : 19- 1. - 1 . ~0 : q.y : , .' , ., =-'_ +.i.fi F3._ ~ 35.J4~G~ . a! 7 J
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contact area 10 between the cold wail chassis and the card ? or strip 5 depending upon the configuration (i.e., strip 5 may not always be present). An end portion of the circuit card ? often includes a protrusion ~ (often machined from base card ?), which allows this module to be compliant with a convection cooled chassis as deFmed in IEEE 11 Ol .2 s Specifications (see, e.g., FIG. 3 for a conventional 11 Ol .2 compliant module used in a convection-cooled chassis). The problett>stic thermal resistances in the module of FIG. i -include the resistance betwoen the metal strip 5 and the chassis cold wall 2 (e.g., about 0.23° C/Vh, between the metal strip 5 end the card 7 (e.g., about 0.3° C!W), and betv<<cen the card 7 and the fraate 1 (e.g., about 0.1 I ° CJV4~. The hatch marks in F1G. 1 represtttt io air gaps. The module of FIG. 1 fails to use appmximatel.y 40°~'s of the cold wall of chassis 2 surface contact area available for conduction; it uses only the surface contact area 10 far thermal conduction, which is typically about 0.635 cm in width.
Additionally, for IEEE 1101.2 purposes, the module must be compliant with the conviction-cooled ' chassis (see, e.g., FIG. 3) so it typically includes the protrusion 4. ;
is In carntrast, the module illustrated in FIG. 2, an embodiment of the new stiffening frame, has improved cooling efficiency when used in a conduction-cooled chassis 2. The .
improved cooling e~clency is achieved, at least in part, through the use of a largo wedgelock 13. In the caibodirnent of FIG. Z, tire wedgelock 3 of FIG. 1 is increased in ;
width from x to x', e.g., from about 0.635 cm to about 0.889 crn. The width is not to be 2p confused with the height which is the expandable portion of the wedgelock.
The , incrwidth x' of the wedgelock 13 identically increases the contact area 20 between .
the frame 11 and the chassis cold wall 2. A second in>portsnt result of the alteration or augmentation is that the fraruc 11 (a restructured frame 1 of FI~G.1 ) is in direct contact with chassis 2, which rrsults in a more direct thermal path. The card T is either the same !
2~ card 7 of F1G. l,pulled back to allow for the placement of frame 11 or a ' i modifiedlshortened version of card 7 with the protrusion 4 removed. The restructuring results in a frame I I that optionally eliminates the protrusion 4 of FIG. I
necessary for use with convection-cooled chassis (but not necessary in a eonduction..c,ooled chassis) or ' optionally maintains the protrusion as in FIGS. 4 and 5. Further, the frame 11 eliminates i 3o the naed for the metal strip 5 of FIG. 1. It should be noted that a reduction and simptificatioa in thermal rcsistances i9 realized in the embodiment illustrated in FIG. 2, .

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where it is r~uced to about O.I ° C/VV bctwccn the framt I 1 and chassis 2 cold wall. In surtvmary~ the ta~rger.sur~arcc contact area betwccn the frame 11 and chassis .
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cold wall as well as the additioantl clamping force from the larger wedgelock 13 results in overall lower component running tempemturcs for this embodiment. The embodiment of FIG. 2 is partially camplia~at with the IEEE I 101.2 Specifications as it does ~aot include a protrusion for use is a tom action-cooled chassis. Ernbadiments having frames that maintain the protrusion and still use a larger wedgelock far increased cooling efficiency are also contemplated, and are discussed below with respect to FIGS. 4 and 5.
A c;otnmetcially-available wedgelock I3 suitable for use in the present invention is the Card-Lok product which can be obtaiu~d from Calnasrk Corp., San Gabriel, CA. In particular, the. adapta~ frame structure of the present invention is designed to allow the use to of large wcdgelocks, e.g., those utilizing larger screws, As described about, the removal of the protrusion 4 allows for as inereast in the width of the contact surface between the frame 1 and chassis 2 by fiom about 0.635 cm to about 0.889 em. Not only is thtre an increase in the surface contact stns of the wedgelock 13 that is in contact with the ether parts of the circuit card module, but the larger wedgelock 13 exerts greater force between t s the frame I to the chassis cold wall 2 than the smaller wedgelack 3 of the prior art. As clamping force is increased, the interface conductance is increased, thus increasing the efficiency of heat movement from the component 6 to the cold wall of chassis 2.
Optionally, the clamping force caa be further increased by using a wedgelock 13 that has a friction-coducing finish applied to it and by installing the wedgelock ~13 with washers.
2o Wedgelocks made of aluminum are profaned, although other materials can be used.
The increased fozce, in combination with the additional contacting surface antes, significaatly reduces the thermal resistance between the franne and the chassis 2 cold wall.
In particular, typical thcrrnal resistances across the wedgalack of conduction-cooled YME 6U modules is about 0.42° CIW. Thus, with an approximately 40 Watt (W) 25 module, for example, thtra is an average 8.3° C tanperaturc rise.
This temperature rise is significantly avoided using the adapter of the prtsent invention. The reduction of thermal resistances and temperature rises is reflected in a reduced running temperature for component 6.
Referring to FIG. 3, there ix shown a prior art circuit card module that is compliant 3o with the IEEE I 101 ~ Specifications and is installed in a convection-cooled chassis 12. A card guide 18 is attached to the convection-cooled chassis 12 with for example, screws, for receiving the card 7 by its protrusion 4. In a conduction-cooled chassis, on the other hand, the channel for receiving the protrusion 4 is machined into the chassis 2 itself as shown in FIGS. l, 2, 5, and 6. The remaining structure of the S circuit card module in FIG. 3 is similar to that discussed above with respect to FIG. 1 (similar reference numerals indicate similar components), with the exclusion of wedgelock 3 and strip 5 which are not present in convection-cooled applications, and need not be discussed again as its structure will be apparent to those skilled in the art.
In a convection-cooled chassis as shown in FIG. 3, airflow, for example, over the circuit card module removes the heat to the ambient environment.
Referring to FIG. 4, there is shown an alternate embodiment of the new stiffening frame installed in a convection-cooled chassis 12. The circuit card module comprises a frame 21, which includes a protrusion 14 that fits in the card guide 18 of the chassis 12 as shown. Although the wedgelock 3 would most likely be used in practice, a larger wedgelock can also be used in this alternate embodiment. The frame 21 allows for a larger wedgelock to be used and for the strip 5 to be eliminated. The remaining structure of the circuit card module in FIG. 4 is similar to that discussed above with respect to FIG. 2 (similar reference numerals indicate similar components) and need not be discussed again as its structure will be apparent to those skilled in the art. However, in the event that the circuit card module is to be used in commercial (non-military) applications and convection cooled, then the wedgelock 3 would not be present.
It is contemplated, however, that certain convection-cooled applications would require the use of an extended width wedgelock and thus, it is shown for purposes of illustration.
For example, if the circuit card modules are integrated (first tested) in a commercial, convection-cooled chassis in a laboratory environment and then installed into the actual chassis, then an extended width wedgelock would be used.
Referring to FIG. 5, there is shown the embodiment as illustrated in FIG. 4 except that the circuit card module is mounted in a conduction-cooled chassis 2. This embodiment has a protrusion 14 and thus, is compliant with the IEEE 1101.2 Specifications. Similar to the embodiment of FIG. 2, the embodiment of FIG. 5 has increased cooling efficiency but remains compatible with a convection-cooled chassis 12. In the embodiment of FIG. 5, however, the surface contact area 30 is not as large as RCV.~\~01~~ : EPA 141UENCIIE~ G 1. : 1 J- 1- 7 . 20 : 50 : . ..". .~ . .,~, °~~E~ 13:)365Ei4-~ +49 t39 23~~'~4 F;o' : il 14 ._~«
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the surface contact area 20 in FIG. 2. Also similar to the embodiment of FIG.
2, a reduction and simplification in thermal resistances is realised in the embodiments illustrated in FIG..S,~whare it is reduced to only between tile frame 21 and chassis cold wall 2 (strip 5 is eliminaud). In any event, an extended width wedgelock allows for s greater surface contact area 30 to improve the thermal performanec.
Referring to FIG. b, there is shown a cross-sectional view of a COTS circuit card module modified with the adapter of the present invelrtion to increase thermal ci~icicncy .
usiae the principles described above (i.e., greater pressure from an extended width wedgelock, increased surface contact area 40, aid extended frat»a to increase the to conduction contact area). The circuit card module of F1G. 6 dots not necessarily have to be co>arlpliant with the IEEE 1101.2 Specifications anal can be any commercially-available ;
circuit card. Many of the COTS conduction-cooled Vhf circuit card modules suffer from the thermal problems described above. The adapter of the present invention shown -in FIG. 6 allows COTS circuit cgrd tnodulcs to obtain the improved thermal performance is and be in compliance with IEEE 11 Ol .2 Specifications when used in a conduction-cooled , chassis. The premise behind the present invention is to provide a wedgclocklchassis interface modification kit to existing modules to increase the cold wall contact area for i improved cooling e~lLciency without a complete redesign of the PWB mechanical interface. The adapter of the present irrvendon requires the removal of the COTS
2o backside abrasion strip (strip 5 in FIG. 1 ), and pountially replacement of wedgelock 3 , with an extended width wedgelock. The attached width dimension should not be confused with the height dimension which consists of the expandable portion of the wcdgelock. These items are replaced with the adapter of the present invention to increaRe the surface area contract between ttie cold waU of the chassis and the strip in contact with 25 card 7 without impaxcting the COTS design. Qnce adapted, however, the CATS
module is not backwards compatible with the convection-cooled type racks. As can be seen from FIG. 5, elements 3 (which can have an extended width),16 and 15 combine to increase .
the conduction contact between the COTS circuit card module and the cold wall of the ' chassis 2. v 3o In the circuit card module of FIG. b, the stxip I 5 (an eletrtent of the adapter) fully cooperates with the bottom surface of tl~ card 7 and its protrusion 4 for an increased REPLACEMENT PAGE
~urfacc contact area 40r i,e., the air gaps of FIG. 1 (shown by hauh msr)cs) between the ,",y, ~ : -~ ~ ~ ... ' . ~~, _ 1 _ 1 . m, : ;» . :?U 1:393EWEi4-~ +~~.cJ. gc~
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chassis cold well, the card 7, and the strip 5 arc substantially filled by the adapter of the presr..nt invention. The frame 1 is either adapted with another piece of material extension 16 to extend to the chassis 2 cold wall or is constructed of one piece (frame 1 integrated with extension 16). The adapter allows the COTS circuit card module to fully utilize the surface contact area 40 between the underside of card 7 and the chassis 2 cold wall, and optionally, the contact area between the wedgelock and frame 1 with 5 extension 16. Thus, the surface contact area between the circuit card module is increased and the thermal performance improved without impacting the existing COTS
design. Also, the wedgelock 3 can be an extended width wedgelock as described above with respect to FIGS. 2, 4, and 5 to further increase the contact area with the frame 1 and extension 16. Comparing the COTS card module of FIG. 1 with that of FIG.
6, it 10 can be seen that the air gaps (shown by hatch marks in FIG. 1 ) have been substantially filled by the adapter (i.e., elements 15 and 16) of the present invention. In particular, the frame 1 is extended with extension 16 to utilize the contact area 40, the width of wedgelock 3 can be extended, and the strip 15 fully utilizes the space under the protrusion 4. The configuration of FIG. 6 significantly reduces the thermal resistance between card 7, strip 15, and chassis 2 cold wall, which reduces the overall junction temperature of the components resulting in improved module reliability.
Predictions using standard thermal analysis software were preformed to measure the expected improvements with the various embodiments of the adapter frame.
The analysis showed that the conventional design, as illustrated in FIG. 1, had a component running temperature of about 98° C. The embodiment illustrated in FIG.
6 had a component running temperature of about 93° C. Such a reduction in running temperatures significantly increases the reliability of the circuit card module, particularly when subjected to the environmental temperatures present when the cards are used in military applications. An additional manner in which to analyze the increased ability of the adapter frame to dissipate heat is to examine the difference in the temperature rise from the base 71 ° C chassis to the component junction. The present invention has the ability to more effectively and dramatically transfer heat from the component 6 of a circuit card to the chassis 2 cold wall.
Other variations and modifications of the present invention will be apparent to those of skill in the art, and it is the intent of the appended claims that such variations and modifications be covered. The particular values and configurations discussed above can be varied and are cited merely to illustrate a particular embodiment of the present invention and are not intended to limit the scope of the invention. It is contemplated that the use of the present invention can involve components having different characteristics as long as the principle is followed, i.e., the presentation of an adapter to existing frames of COTS circuit card modules for improving their thermal efficiency allowing for a larger surface area contact between the chassis and the frame.
It is intended that the scope of the present invention be defined by the claims appended hereto.

Claims

What is claimed is:

1. An improvement to a circuit card module cooperating with a conduction-cooled chassis (2) that receives the circuit card module resulting in increased cooling efficiency, the circuit card module having at least one printed wiring board (PWB) (7, 8), the PWB (7, 8) having a protrusion (4) at one end thereof, at least one component (6) operatively connected to the PWB (7, 8), a heat path between the component (6) and the chassis (2), and a frame (1) in contact with the PWB (7, 8) for stiffening the PWB (7, 8), the improvement comprising:

an adapter, wherein said adapter comprises a thermally conductive strip (15) axed to a bottom surface of the PWB (7), wherein said strip (13) comprises a predetermined surface area of the PWB and the protrusion (4), and a frame extension (16) affixed to a top surface of the protrusion (4), wherein said frame extension (16) comprises substantially all of a top surface area of the protrusion (4).

2. The circuit card module of Claim 1, wherein said frame extension (16) comprises an integrated frame extension with the frame (1).

3. The circuit card module of Claim 1, wherein said adapter is constructed of two ar more pieces.

4. The circuit card module of Claim 1, further comprising a wedgelock (3) comprising a predetermined surface area of said frame (1) and a frame extension (16) that secures said adapter to the chassis (2) via pressure, wherein the wedgelock (3) causes a pressure to be exerted over the increased surface area between said adapter and the chassis

5. The circuit card module of Claim 4, wherein said wedgelock (3) has a temperature rise per watt of power dissipation of approximately .21°C/W.