Need heat sink sources (manufacturers or distributors)

[jode]

Hello all, I am working on a project for an automotive ignition module. The module requires a heatsink, and we thought the best solution might be to use a heatsink that could also double as the exterior casing of the product. Car stereo amplifiers and AC/DC power inverters often do the same thing in that when you look at the product, you are actually seeing the heat sink. Usually, they are (what appears to be) an extruded tube with exterior fins with the electronics inside, and metal end caps to close off the extruded tube.

I would like to use something similar for this project, and wonder if any of you could point me to a manufacturer or distributor of something that might meet the following requirements. As of now, the extrusion must be between 3-7" wide, and between 1-3" tall.

Thanks in advance....

 

[sreid]

Take a look at

Aavid

Themalloy

R-Theta

All sell unfinished extrusions whitch can then be cut/machined/finished as needed.

 

[ko99]

There are many aluminum extruders who can do this. You can google to find some in your area. Some of the bigger houses may already have a die that meets your needs:

http://www.aavidthermalloy.com/

http://www.alexandriaextrusion.com/aec/index.cfm

http://www.taconet.com.tw/altec/

http://www.jmcproducts.com/index.shtml

http://www.psiextrusions.com/contact.html

http://www.wakefield.com/

There's also aluminum metal injection molding:

http://www.amt-mat.com/products_alumim.htm

And aluminum casting: many sources

Note that the molded and cast parts do NOT have the same conductivity as extruded parts, but often it can be compensated for in the design.

I also recommend you do some homework to find the optimal fin thickness and spacing. The wrong design could easily be 2-3X hotter than an optimal design in the same volume. Some extruders have thermal engineers that can help you.

ko (

http://www.ecooling.biz)

 

[jode]

Thanks to all for the responses. It has been amazing to me how difficult it has been to find a suitable product. I guess the reason may be that I am looking for a combination case/heat sink.

The case seen at the following link (copy and paste it into your browser):

http://www.taconet.com.tw/AdTaconet...O=cecf258282780de657d70eaf9384304d|1119475853

is pretty much what we are looking for. However, there is one problem, since we will be using the case itself as a heat sink, the bottom of the case needs to be of sufficient thermal mass that it can absorb, and distribute the heat to the rest of the body of the case. The heat load is not great, and the case itself will have plenty of surface area to conduct the heat away, but we are concerned that with such a thin section of aluminum right where the heat load is applied, that it will not be able to take advantage of the rest of the surface area of the case as a heat sink.
Does anyone have any thoughts on this?
Also, does anyone know of a case manufacturer that would be able to offer an off-the-shelf case that has a thicker bottom plate?
Thanks again

 

[sreid]

Possibly "Rose Boxes" from Rose+Bopla.

http://www.rose-bopla.com/PMX/RSBPC...c802b739a9b04f7f85256bb5004eb68d?OpenDocument

 

[ko99]

I couldn't read your link and I'm not aware of any off-the-shelf finned cases. In the long run it may make more sense to spend $500-1000 for a custom extrusion or simply fasten a heat sink to your case. But as you said, the heat must spread (conduct) to take advantage of the case surface area for convection.

Check out the following link for a method (and calculator) for estimating the thermal spreading resistance of your case

http://www.coolingzone.com/Content/DesignCaorner/CZ_Calc/baseframe.htm

ko (

http://www.ecooling.biz)

 

[jode]

Because of some funky stuff in that link, you will have to copy it and paste the link into your browser in order to view it.
The reason we don't want to go the custom extrusion route is that these cases are found commonly in all kinds of inverters and amplifiers. They are out there, someone is making them, and we just want to get some that are already being made.

 

[ScottyUK]

jode,

They are out there (the extrusions, not the little green men), but the high volume users probably own the extrusion die or have paid a steep tooling charge for exclusive use of it. Speak directly to Aavid Thermalloy or IMI-Marston directly rather than trawling their websites. Aavid in particular have some very clued up guys in their tech. sales. They've helped me in the past, and if they don't make what you're after I'm sure they will have some ideas who does. It is their industry after all.



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