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Bill Fagal · 04-23-2003, 01:41 PM

Alright, here's a finite element flux density plot. I roughly modeled the outer dimensions based on the info on Adire's website. I specd 1006 steel pole/top-plate and grade-8 ceramic magnets. (I don't know if they use grade-8 or 5, so I gave them the benefit of the doubt--certainly enough to saturate the pole.)

I'm just guessing at the top-plate geometry, but a really scooped-out channel between the gaps seems to model best, and saves weight to boot.

Take the actual values with a grain of salt since there are so many unknown variables (like, for example, whether or not this is actually XBL2 at all.

)

http://image1ex.villagephotos.com/pu...sp?id_=2299011

Notice the symmetry of the fringing fields and negligible flux between the gaps. I believe these are crucial to the design to keep BL constant from inward VC excursion, across the gap crossover zone, and through outward excursion.

These twin gaps allow the VC to completely traverse a magnetic gap with each half cycle, shortening the winding hight necessary to achieve a given excursion. Brilliant!

I don't know if anyone else out there has any interest in this stuff, but driver design is what I do for fun, so I find this line of conjecture facinating.

Bill

Edit: Switched to a link--bandwidth, ya know..

04-23-2003, 01:41 PM	#4 of 34
Bill Fagal Member Join Date: Jul 2002 Local Time: 03:07 AM Local Date: 01-09-2009 Posts: 165	Alright, here's a finite element flux density plot. I roughly modeled the outer dimensions based on the info on Adire's website. I specd 1006 steel pole/top-plate and grade-8 ceramic magnets. (I don't know if they use grade-8 or 5, so I gave them the benefit of the doubt--certainly enough to saturate the pole.) I'm just guessing at the top-plate geometry, but a really scooped-out channel between the gaps seems to model best, and saves weight to boot. Take the actual values with a grain of salt since there are so many unknown variables (like, for example, whether or not this is actually XBL2 at all. ) http://image1ex.villagephotos.com/pu...sp?id_=2299011 Notice the symmetry of the fringing fields and negligible flux between the gaps. I believe these are crucial to the design to keep BL constant from inward VC excursion, across the gap crossover zone, and through outward excursion. These twin gaps allow the VC to completely traverse a magnetic gap with each half cycle, shortening the winding hight necessary to achieve a given excursion. Brilliant! I don't know if anyone else out there has any interest in this stuff, but driver design is what I do for fun, so I find this line of conjecture facinating. Bill Edit: Switched to a link--bandwidth, ya know..