Assem Bling And Disassem Bling The Depressed Center Wheel; Maintenance And Inspection - Hitachi Koki G 23MR Handling Instructions Manual

Too m uch pressure w ill result in reduced rotational
speed, inferior surface finish, and overloading w hich
could reduce the life of the m achine.
2. Grinding angle
Do not apply the entire surface of the depressed
center w heel to the m aterial to be ground. As
show n in Fig. 3, the m achine should be held at an
angle of 15° – 30° so that the external edge of the
depressed center w heel contacts the m aterial at an
optim um angle.
3. To prevent a new depressed center w heel from
digging into the w orkpiece, initial grinding should
be perform ed by draw ing the grinder across the
w orkpiece tow ard the operator (Fig. 3 direction B).
Once the leading edge of the depressed center
w heel is properly abraded, grinding m ay be
conducted in either direction.
4. Sw itch operation
Sw itch ON: Push the locking button forw ard and
then press the sw itch lever.
* For continuous use, press the sw itch
lever. The sw itch lever is locked by
pushing the locking button forw ard
once again.
(* Subject to change depending on
area.)
Sw itch OFF: Press and release the sw itch lever.
5. Precautions immediately after finishing operation
After sw itching off the m achine, do not put it dow n
until the depressed center w heel has com e to a
co m p l et e st o p . A p ar t f r o m av o i d i n g ser i o u s
accidents, this precaution w ill reduce the am ount
of dust and sw arf sucked into the m achine.
CAUTIONS
Check that the w ork piece is properly supported.
Ensure that ventilation openings are kept clear w hen
w orking in dusty conditions.
If it should becom e necessary to clear dust, first
disconnect the tool from the m ains supply (use non-
m etallic objects) and avoid dam aging internal parts.
Ensure that sparks resulting from use do not create
a hazard e.g. do not hit persons, or ignite flam m able
substances.
Alw ays use eye and ear protection.
Other personal protective equipm ent such as dust
m ask, gloves, helm et and apron should be w orn
w hen necessary.
If in doubt, w ear the protective equipm ent.
When the m achine is not use, the pow er source
should be disconnected.
ASSEM BLING AND DISASSEM BLING THE
DEPRESSED CENTER WHEEL
CAUTION Be sure to sw itch OFF and disconnect the
attachm ent plug from the receptacle to avoid
a serious accident.
1. Assembling (Fig. 1)
(1) Turn the m achine upside dow n so that the spindle
is facing upw ard.
(2) M ount the w heel w asher onto the spindle.
(3) Fit the protruding part of the depressed center
w heel or diam ond w heel onto the w heel w asher.
(4) Screw the w heel nut onto the spindle.
(For diam ond w heel assem bling, use the w heel nut
w ith the convex side against the diam ond w heel.)
(5) Insert the push button to prevent rotation of the
spindle, and tighten the w heel nut w ith the accessory
w rench, as show n in Fig. 1.
2. Disassembling
Follow the above procedures in reverse.
CAUTIONS
Com firm that the depressed center w heel is m ounted
firm ly.
Confirm that the push button is disengaged by
pushing push button tw o or three tim es before
sw itching the pow er tool on.
M AINTENANCE AND INSPECTION
1. Inspecting the depressed center w heel
Ensure that the depressed center w heel is free of
cracks and surface defects.
2. Inspecting the mounting screw s
Regularly inspect all m ounting screw s and ensure
that they are properly tightened. Should any of the
screw s be loose, retighten them im m ediately. Failure
to do so could result in serious hazard.
3. Inspecting the carbon brushes (Fig. 4)
The m otor em ploys carbon brushes w hich are
consum able parts.
When they becom e w orn to or near the " w ear
lim it" , it could result in m otor trouble. When an
auto-stop carbon brush is equipped, the m otor w ill
stop autom atically.
At that tim e, replace both carbon brushes w ith new
ones w hich have the sam e carbon brush num bers
show n in the figure. In addition, alw ays keep carbon
brushes clean and ensure that they slide freely
w ithin the brush holders.
4. Replacing carbon brushes (Fig. 5)
〈 Disassem bly 〉
(1) Loosen the D4 tapping screw retaining the brush
cover and rem ove the brush cover.
(2) Use the auxiliary hexagonal w rench or sm all
screw driver to pull up the edge of the spring that
is holding dow n the carbon brush. Rem ove the
edge of the spring tow ard the outside of the brush
holder.
(3) Rem ove the end of the pig-tail on the carbon brush
from the term inal section of brush holder and then
rem ove the carbon brush form the brush holder.
〈 Assem bly 〉
(1) Insert the end of the pig-tail of the carbon brush
in the term inal section of brush holder.
(2) Insert the carbon brush in the brush holder.
(3) Use the auxiliary hexagonal w rench or sm all
screw driver to return the edge of the spring to the
head of the carbon brush.
(4) M ount the tail cover and tighten the D4 tapping
screw .
5. M aintenance of the motor
The m otor unit w inding is the very " heart" of the
pow er tool. Exercise due care to ensure the w inding
does not becom e dam aged and/or w et w ith oil or
w ater.
6. Service parts list
A: Item No.
B: Code No.
C: No. Used
D: Rem arks
English
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