Hitachi C 12FSA Technical Data And Service Manual page 11

Measuring methods and surface roughness
Fig. 16 shows an example of roughness (extent of
surface unevenness) measured at points A , B and
C of the workpiece (cut in the conditions indicated
in Table 7) by moving the probe of the roughness
gauge in the direction indicated by the arrow in
Fig. 15. Table 8 shows the maximum values
obtained by such measurement. As seen in
Table 8, the C 12FSA produces a smoothly finished
surface with minute roughness as the C 10FS.
Table 8 Surface roughness (Max. values)
Maker
Model
Measuring
points
A
B
C
(7) Minimized reaction during motor start
The C 12FSA uses the soft-start system to suppress sound pressure level when starting and reaction
transmitted through the handle.
Sound pressure level and reaction when starting are as indicated in Table 9.
A normal speed is reached quickly with minimum sound pressure level when starting.
It is readily seen from Table 9 that the electronically controlled soft start is highly effective.
Item
Sound pressure
level when starting (dB/A) *2
Reaction (P) when
starting (kg) *3
*2 Sound pressure level when starting: Maximum
value measured at 1 m distance from the front
(8) Poly V belt overload protection
C 12FSA utilizes the poly V belt to transmit the rotation of the motor to the saw blade instead of a conventional
gear transmission system. This is to reduce noise, however, there is a fear of cutting the poly V belt during
overload. To protect the poly V belt, an overload protection circuit is equipped in C 12FSA. The overload
protection circuit stops the motor revolution before the motor locks when an excessive or abnormal load is
applied to the poly V belt, and so protects the poly V belt.
(Unit: µm)
HITACHI HITACHI
C 12FSA C 10FS
39 36
39 38
38 39
Table 9
Maker
HITACHI
Model
C 12FSA
86
0.5 or less
Press cutting
A : Around the start
of press cutting
B : Around the lower bottom
at press cutting
*3 Reaction when starting is a force exerted to
the handle in the direction of lifting the handle.
--- 7 ---
Slide cutting
300 mm (11-13/16")
: Slide cutting
C
Fig. 16
P
Fig. 17
Saw
marks
64 mm 2-17/32"
(Left 45˚ bevel
cutting surface
height)
Handle