Bosch GBH 3-28 DFR Perforateur Manuel De L'utilisateur page 19

OBJ_BUCH-770-008.book Page 18 Wednesday, June 15, 2016 2:12 PM
18 | English
Operation
Starting Operation
 Observe correct mains voltage! The voltage of the pow-
er source must agree with the voltage specified on the
nameplate of the machine. Power tools marked with
230 V can also be operated with 220 V.
Setting the operating mode
The operating mode of the power tool is selected with the
mode selector switch 9.
Note: Change the operating mode only when the machine is
switched off! Otherwise, the machine can be damaged.
– To change the operating mode, push the release button 8
and turn the mode selector switch 9 to the requested posi-
tion until it can be heard to latch.
Position for hammer drilling in concrete or
stone
Position for drilling without impact in wood,
metal, ceramic and plastic as well as for
screwdriving
Vario-Lock position for adjustment of the
chiselling position
The mode selector switch 9 does not latch in
this position.
Position for chiselling
Reversing the rotational direction
The rotational direction switch 13 is used to reverse the rota-
tional direction of the machine.
 Actuate the rotational direction switch 13 only when
the machine is at a standstill.
Right rotation: Turn the rotational direction switch 13 to
the stop in position .
Left rotation: Turn the rotational direction switch 13 to
the stop in position .
Set the direction of rotation for hammer drilling, drilling and
chiselling always to right rotation.
Switching On and Off
To save energy, only switch the power tool on when using it.
– To start the machine, press the On/Off switch 7.
– To switch off the machine, release the On/Off switch 7.
1 609 92A 2A9 | (15.6.16)
Setting the Speed/Impact Rate
The speed/impact rate of the switched on power tool can be
variably adjusted, depending on how far the On/Off switch 7
is pressed.
Light pressure on the On/Off switch 7 results in low speed/im-
pact rate. Further pressure on the switch increases the
speed/impact rate.
Overload Clutch
 If the tool insert becomes caught or jammed, the drive
to the drill spindle is interrupted. Because of the forces
that occur, always hold the power tool firmly with both
hands and provide for a secure stance.
 If the power tool jams, switch the machine off and loos-
en the tool insert. When switching the machine on with
the drilling tool jammed, high reaction torques can oc-
cur.
Working Advice
 Before any work on the machine itself, pull the mains
plug.
 Hold the tool by the insulated gripping surfaces when
performing operations where the application tool or
the screw could contact hidden wiring or its own power
cord. Contact with a "live" wire will also make exposed
metal parts of the power tool "live" and shock the operator.
Changing the Chiselling Position (Vario-Lock)
The chisel can be locked in 36 positions. In this manner, the
optimum working position can be set for each application.
– Insert the chisel into the tool holder.
– Turn the mode selector switch 9 to the "Vario-Lock" posi-
tion (see "Setting the operating mode", page 18).
– Turn the tool holder to the desired chiselling position.
– Turn the mode selector switch 9 to the "chiselling" posi-
tion. The tool holder is now locked.
– For chiselling, set the rotation direction to right rotation.
Inserting Screwdriver Bits (see figure L)
 Apply the power tool to the screw/nut only when it is
switched off. Rotating tool inserts can slip off.
To work with screwdriver bits, a universal bit holder 28 with
SDS-plus shank (accessory) is required.
– Clean the shank end of the adapter shank and apply a light
coat of grease.
– Insert the universal bit holder with a turning motion into
the tool holder until it automatically locks.
– Check the locking effect by pulling the universal bit holder.
– Insert a screwdriver bit into the universal bit holder. Use
only screwdriver bits that match the screw head.
– Turn the mode selector switch 9 to the "drilling" position.
– To remove the universal bit holder, pull the locking sleeve
5 toward the rear and remove the universal bit holder 28
out of the tool holder.
Bosch Power Tools