Sharp FDD-412A - Page 25

FDD412A/B
2.5.3 Magnetic Head Composition and Its Related Operations
(1) Magnetic head composition
As shown in Fig. 2.15, the magnetic head has 2 gaps as a read/write
head and an erase head. The magnetic head is housed in a slider
and secured with a "gimbals" mechanism to the carriage.
Table 2.10 shows how the magnetic head moves and what it features.
Erase head
oot; %=300 um TYP
ie
Envelope
\ Gimbals mechanism
Read/write head
Fig.
2.15
Magnetic
Head
Composition
Table
2.10
Movements
and
Features
of
Magnetic
Head
Item
Contents
_
Name
Tunnel-erase
type
magnetic
head
Features
(1)
The
read/write
head
and
erase
head
are
far
apart
and
do
not
affect
one
another.
(R/W
current:Erase
current
= 1:10)
(2)
Envelope
waveshapes,
with
both
sides
erased
by
the
the
erase
head,
are
much
better.
(3)
The
read/write
head
and
erase
head
need
to
be
electrically
corrected
in
operational
timing.
(ERASE
GATE)
|
(4)
The
disk
sides
and the
heads
come
into
stable.
contact
under
a
"pinching"
spring
pressure
from
the
gimbals
mechanism.
Head
on/off
O
eas
mechanism
)
6)
®
@
a
ae
@o
~—
Head
0
@ The FDD door is open.
@ The FDD door is closed.
@ The head is loaded on.
(2)
Tunnel
erase
system
The
tunnel
erase
system
is
used
to
guarantee
data
compatibility.
The
following
are
the
reasons
why
this
system
is
needed:
-19—