Maintenance And Inspection - Hitachi DH 50MB Mode D'emploi

English
CAUTION:
During operation, be sure to grip the handle and
the side handle firmly to prevent your body from
swaying.
(1) Switching to "rotation + hammering"
For switching to "rotation + hammering", follow the
same procedures mentioned in [3. When drilling
at "rotation + hammering"].
(2) Attaching chuck adapter to drill chuck (Fig. 14)
(a) Attach the chuck adapter to the drill chuck.
(b) The SDS max shank of the chuck adapter is
equivalent to the drill bit. Therefore, follow the
same procedures as [How to install tool] for
attaching and detaching drill bits.
(3) Drilling
(a) Even if you apply more-than-required pressure
to the machine body, drilling can never be
performed as quickly as you expect. Applying
more force or pressure to the machine body
than what is needed, on the contrary, damages
the drill tip, resulting in the declined working
efficiency and shortened life of this machine.
(b) A drill can snap sometimes when drilling is
almost finished. It is important to relax your
thrusting pressure when drilling is nearing the
end.
HOW TO HANDLE A CORE BIT
When a core bit is used, large diameter holes and blind
holes can be drilled. In this case, use optional accessories
for core bits (such as a center pin and core bit shank) for
more efficient operation.
1. Mounting
CAUTION:
Prior to mounting a core bit, always disconnect the
plug from the receptacle.
(1) Mount the core bit on the core bit shank. (Fig. 15)
Before that, feed oil to the screw portion of core
bit shank for easy dismounting.
(2) Mount the core bit shank on the main body in the
same manner as in mounting the drill bit and the
bull point. (Fig. 16)
(3) Insert the center pin into the guide plate until it
reaches the extremity.
(4) Fit in the guide plate by aligning its concaved
portion with the core bit tip. When the position of
the concave is shifted by turning the guide plate
right or left, the guide plate never slips off even
when the drill is used in a downward direction.
(Fig. 17)
2. Drilling holes
(1) Insert the plug into a receptacle.
(2) A spring is built in the center pin. By straightly and
gently pressing it to the wall or floor surface, the
entire surface of the core bit tip attains contact to
start the hole drilling job. (Fig. 18)
(3) When the hole depth reaches approximately 5 mm,
the hole position can be determined. Then remove
the center pin and guide plate from the core bit and
continue the hole drilling job.
CAUTION:
When removing the center pin and guide plate,
always disconnect the plug from the receptacle.
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3. How to dismount the core bit
By holding the rotary hammer (with the core bit
inserted) in an upward position, drive the rotary
hammer to repeat impact operation two or three
times, whereby the screw is loosened and the rotary
hammer becomes ready for disassembly. (Fig. 19)
Remove the core bit shank from the rotary hammer,
hold the core bit with one hand, and strongly strike
the head of the SDS max shank portion of the core
bit shank with a manual hammer two or three
times, whereby the round head screw is loosened
and the rotary hammer is ready for disassembly.
(Fig. 20)
HOW TO REPLACE GREASE
This machine is of full air-tight construction to protect
against dust and to prevent lubricant leakage. Therefore,
the machine can be used without lubrication for long
periods. Replace the grease as described below.
1. Grease replacement period
After purchase, replace grease after every 6 months
of usage. Ask for grease replacement at the nearest
Hitachi Authorized Service Center. Proceed for
replacement of grease.
2. Grease replenishment
CAUTION:
Before replenishing the grease, turn the power off
and pull out the power plug.
(1) Remove the crank case cover and wipe off the
grease inside. (Fig. 21)
(2) Supply 20g of Hitachi Electric Hammer Grease A
(Standard accessory, contained in a tube) into the
crank case.
As the tube contain 30g of grease, supply 2/3 of
the contained grease.
(3) After replenishing the grease, install the crank case
cover securely.
NOTE:
The Hitachi Electric Hammer Grease A is of the low
viscosity type. If necessary purchase from an Hitachi
Authorized Service Center.

MAINTENANCE AND INSPECTION

1. Inspecting the tool
Since use of a dull tool will degrade efficiency and
cause possible motor malfunction, sharpen or
replace the tool as soon as abrasion is noted.
2. 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. Failure
to do so could result in serious hazard.
3. 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.
4. Regarding indication lamp (red) for carbon brush
replacement (Fig. 22)
When the time for carbon brush replacement nears,
an indication lamp will light up in red as you turn
the switch on. When the indication lamp lights up,
replace both carbon brushes with new ones as early
as you can.