BRUEL & KJAER System V - Perm a Nent Magnet Body, Ty Pe 4 8 05

5. PERMANENT MAGI\IET BODY, TYPE 4805
Centre Post
Hale for Loeating Pin
Magnetic Structure------! ....... ~
~ ____ Permanent
Magnets
Hale
for Cooling
Fo
am Rubber -----IIjool,~
7 40015
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Fig.5 . 1. Cross-sectional drawing of the Permanent Magnet Body
Fig.5.1 shows a cross-sectional drawing of the Permanent Magnet Body. The magnetic
field is supplied by a stack of annular magnets held in position by a cast iron magnetic
structure, which also serves to contain the magnetic fie ld in the Exciter Body as much as
possible The stainless steel center post is basically the same as that of the Type 4801 in
order that all the Heads may fit. The 10 mm mounti ng holes are also shown. A foam rub-
ber annulus at the base serves to isolate the Shaker from its surroundings.
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NOTE:
U sers working around the 4805 are advised to remove wristwatches. Even w hen
the Head is mounted, there is a strong field down the side of the Body, at just about the
point where one might wrap one's arms around it to li ft it.
E
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