Maintenance And Inspection - Hitachi DV 20V2 Handling Instructions Manual

English
CAUTIONS
Exercise care not to excessively prolong driving
time, otherwise, the screws may be damaged by
excessively force.
Apply the screwdriver perpendicularly to the screw
head when driving a screw; otherwise, the screw
head or bit will be damaged, or driving force will
not be fully transferred to the screw.
4. When driving wood screws
(1) Selecting a suitable driver bit
Employ plus-head screws, if possible, since the
driver bit easily slips off the heads of minus-head
screws.
(2) Driving in wood screws
Prior to driving in wood screws, make pilot holes
suitable for them in the wooden board. Apply the
bit to the screw head grooves and gently drive the
screws into the holes.
After rotating the screwdriver at low speed for a
while until a wood screw is partly driven into the
wood, squeeze the trigger more strongly to obtain
the optimum driving force.
CAUTION
Exercise care in preparing a pilot hole suitable for
the wood screw taking the hardness of the wood
into consideration. Should the hole the excessively
small or shallow, requiring much power to drive
the screw into it, the thread of the wood screw may
sometimes be damaged.

MAINTENANCE AND INSPECTION

1. Inspecting the driver bit
Since continued use of a worn driver bit will damage
screw heads, replace the driver bit as soon as
excessive wear is noticed.
2. Inspecting the drill bit
Continued use of a worn and/or damaged drill bit
will result in reduced drilling efficiency and may
seriously overload the drill motor. Inspect the drill
bit ferquently and replace it as necessary.
3. Inspecting the mounting screws
Regularly inspect all mounting screws and ensure
that they are properly tightened. Should any of the
screws be loose, retighten them immediately. Fail-
ure to do so could result in serious hazard.
4. Inspecting the carbon brushes (Fig. 4)
The motor employs carbon brushes which are
consumable parts. Since an excessively worn car-
bon brush can result in motor trouble, replace the
carbon brush with a new one having the same
carbon brush No. shown in the figure when it
becomes worn to or near the "wear limit". In
addition, always keep carbon brushes clean and
ensure that they slide freely within the brush holders.
5. Procedure of disassembling and reassembling the
handle for replacing a carbon brush, power supply
cord, etc. (Fig. 3 and 8)
Disassembling
(1) Loosen B three D4 × 16 tapping screws on the
handle (A). (Fig. 8)
(2) Turn over the body and loosen B two D4 × 16
tapping screws on the handle (B). (Fig. 3)
20
(3) Then remove the handle (B).
Reassembling
Reassembling can be accomplished by following
procedure of disassembling in reverse.
CAUTION
(1) When disassembling, be sure to remove the
handle (B). If the handle (A) is removed, the
internal wiring in the handle will be damaged.
(2) When reassembling, be sure that the internal
wiring is not prinched by the handle or does
not come in contact with the rotating parts of
the motor.
If the internal wiring is pinched by the handle
or comes in contact with the rotating parts of
the motor, a serious danger of electric shock to
the operator will be created.
6. Replacing a carbon brush (Fig. 5)
Disassembling
(1) Remove the handle (B) according to aforesaid "5.
Procedure of disassembling and reassembling the
handle for replacing a carbon brush, power supply
cord, etc. (Fig. 3 and 8)."
(2) Lift out the brush holder together with the carbon
brush.
(3) Withdraw the brush terminal, and remove the carbon
brush from the brush holder.
Reassembling
(1) Place a new carbon brush into the brush holder,
and connect the brush terminal to the carbon brush.
(2) Return the brush holder and other parts to their
original positions, as illustrated in Fig. 5.
(3) Ensure that the lead wire and other parts are properly
positioned.
(4) Reassemble the handle (B) according to aforesaid
"5. Procedure of disassembling and reassembling
the handle for replacing a carbon brush, power
supply cord, etc. (Fig. 3 and 8)."
7. Maintenance of the motor
The motor unit winding is the very "heart" of the
power tool. Exercise due care to ensure the winding
does not become damaged and/or wet with oil or
water.
NOTE
Due to HITACHI's continuing program of research and
development, the specifications herein are subject to
change without prior notice.
Information concerning airborne noise and vibration
The measured values were determined according to
EN50144.
The typical A-weighted sound pressure level:
102 dB (A) (DV20V2·DV20V3·DV20T)
98 dB (A) (DV14V)
The typical A-weighted sound power level:
115 dB (A) (DV20V2·DV20V3·DV20T)
111 dB (A) (DV14V)
Wear ear protection.
The typical weighted root mean square acceleration
2
value: 14,0 m/s (DV20V2·DV20V3·DV20T)
13,0 m/s 2 (DV14V)