Hitachi DH 18DPA User manual

REPAIR GUIDE ---------------------------------------------------------------------------------------------------------------- 1
1. Precautions on disassembly and reassembly ----------------------------------------------------------- 1
• Disassembly -------------------------------------------------------------------------------------------------- 1
• Reassembly -------------------------------------------------------------------------------------------------- 4
• Checking after reassembly ----------------------------------------------------------------------------- 12
• Tightening torque ------------------------------------------------------------------------------------------ 12
• No-load current -------------------------------------------------------------------------------------------- 12
• Lubrication points and types of lubricant ------------------------------------------------------------ 13
• Wiring diagram --------------------------------------------------------------------------------------------- 16
2. Precautions on disassembly and reassembly of the charger---------------------------------------- 17
CONTENTS Page
D
CONFIDENTIAL
Jan. 2021
Overseas Sales Management Dept.
PRODUCT NAME
Cordless Rotary Hammer
Models 18 V DH 18DPA
10.8 V DH 12DD
DH 18DPA
DH 12DD
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-1-
Fig. 1 • Disassembly of the tool retainer ass’y
WARNING: Be sure to remove the battery from the main body before starting repair or maintenance
work. If the switch is activated inadvertently with the battery still mounted on the main
body, the motor may turn unexpectedly and could cause serious injury.
1. Precautions on disassembly and reassembly
[Bold] numbers in the description below correspond to the item numbers in the parts list and exploded
assembly diagram for the Model DH 18DPA and {Bold} numbers to those for the Model DH 12DD.
1. Disassembly of the tool retainer ass’y
Fully pull the Grip [4]{4} in the arrow direction and remove the Front Cap [2]{2}. Remove the Stopper Ring
[3]{3} with a retaining ring puller while pulling the Grip [4]{4} in the arrow direction. Remove the Grip [4]{4},
Ball Holder [5]{5}, Steel Ball D7.0 [19]{19}, Holder Plate [6]{6}, and Holder Spring [7]{7} from the Cylinder
[20]{20}.
NOTE: Do not reuse the removed Stopper Ring [3]{3} as it is deformed at disassembly. Be sure to
use the new Stopper Ring [3]{3} at reassembly.
Disassembly
REPAIR GUIDE
[3]{3}
[7]{7} [5]{5}
[4]{4}
[2]{2}
[20]{20}
[19]{19}
[3]{3}
[6]{6}
[4]{4}
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-2-
Fig. 2 • Disassembly of inner cover (B) ass’y
Fig. 3 • Disassembly of second shaft (A) ass’y
2. Disassembly of the hammering mechanism
(1) Removal of the gear cover
Set the Change Lever [11]{11} to the "Rotation + Hammering" ( mark) position. Remove the four
Tapping Screws (W/Flange) D4 x 30 (Black) [8]{8} to remove the Gear Cover [9]{9}.
(2) Disassembly of inner cover (B) ass’y
Remove the two Seal Lock Hex. Socket Hd. Bolts M5 x 14 [34]{34} from Inner Cover (B) [35]{35}.
Remove the assembly of the Piston [31]{31} and Second Shaft (A) [43]{43} from Inner Cover (A) Ass’y
[49]{49}.
NOTE: The Seal Lock Hex. Socket Hd. Bolt M5 x 14 [34]{34} loses its bonding force if removed.
Use the new Seal Lock Hex. Socket Hd. Bolt M5 x 14 [34]{34} at reassembly.
(3) Disassembly of second shaft (A) ass’y
Engage the claw of the Clutch [44]{44} with the claw of the Reciprocating Bearing [45]{45} and place
the Clutch [44]{44} on a cradle as shown in Fig. 3. Push the rear end of Second Shaft (A) [43]{43} with
a hand press to push out the Bevel Gear [48]{48} from Second Shaft (A) [43]{43}. Then, remove Thrust
Washer (C) [47]{47}, Reciprocating Bearing [45]{45}, Needle Cage [46]{46}, and Clutch [44]{44} from
Second Shaft (A) [43]{43}.
[49]{49} [31]{31}
[35]{35}
[43]{43}
[48]{48}
[47]{47} [45]{45}
[44]{44}
[43]{43} [46]{46}
Hand press
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-3-
Fig. 4 • Removal of the parts from the inside of the cylinder
3. Disassembly of the cylinder assembly
(1) Disassembly of the slip clutch ass’y
Remove the Machine Screw M4 x 5 [14]{14} that fixes the Change Lever [11]{11} and Stopper [13]{13}
in the Gear Cover [9]{9}. Pull out the Change Lever [11]{11} and Stopper [13]{13} from the Gear Cover
[9]{9}. Push the tip of the Cylinder [20]{20} to remove it from the Gear Cover [9]{9}. Use the retaining
ring puller to pull out the Retaining Ring for D25 Shaft [15]{15} from the Cylinder [20]{20}. Then remove
the Second Gear [18]{18}, Spring (A) [17]{17}, and Washer [16]{16} from the Cylinder [20]{20}.
(2) Removal of the parts from the inside of the cylinder
NOTE: Use the special repair tools specified in the
table for removal of the parts from the
inside of the Cylinder [20]{20}.
Insert the J-407 stopper ring jig into the Cylinder
[20]{20} as shown in Fig. 4 until it contacts the end of
the Hammer Holder [24]{24}.
Clamp the ends of the Cylinder [20]{20} and J-407 stopper ring jig with a vise to compress the O-ring
[23]{23}. Insert the J-341 punch (C) into the two 4-mm dia. hole (2 places) on the Cylinder [20]{20} and
hammer the punch head to give force to the periphery of the Stopper Ring [25]{25} in order to detach
the Stopper Ring [25]{25} from the bore groove of the Cylinder [20]{20}. At this time, fully hammer along
the periphery of the Stopper Ring [25]{25} until the Stopper Ring [25]{25} disappears from the two 4-
mm dia. holes. Then unclamp the Cylinder [20]{20} from the vise and use J-341 ring puller jig (B) to pull
out the Stopper Ring [25]{25} from the inner circumference of the Cylinder [20]{20}.
NOTE: • Be careful not to let the Stopper Ring [25]{25} pop out. Once the Stopper Ring [25]{25}
is detached from the Cylinder [20]{20}, the Hammer Holder [24]{24}, O-ring [23]{23}, and
Second Hammer [22]{22} can be removed from the Cylinder [20]{20}.
• Do not reuse the removed Stopper Ring [25]{25} and O-ring (C) [23]{23} as they are
deformed at disassembly. Be sure to use the new Stopper Ring [25]{25} and O-ring (C)
[23]{23} at reassembly.
Hammer
J-341 punch (C)
4-mm dia. hole
Vise Vise
[25]{25}
J-407 stopper ring jig
[20]{20}
[24]{24}
Special repair tool Code No.
J-407 Stopper ring jig 376747
J-341 Ring puller jig (B) 324203
Punch (C) 324204
4-mm dia. hole
[23]{23}
[22]{22}
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-4-
Fig. 5 • Reassembly of the cylinder ass’y
Reassembly can generally be conducted by reversing the disassembly procedure. However, special
attention should be given to the following items.
1. Reassembly of the cylinder ass’y
NOTE: Use the special repair tool specified in the
table for mounting the parts to the inside
of the Cylinder [20]{20}.
(1) Insert the new O-ring [23]{23} into the Cylinder [20]{20} as shown in Fig. 5. Then, insert the assembly
of the Hammer Holder [24]{24}, O-ring (B) [21]{21}, and Second Hammer [22]{22} into the Cylinder
[20]{20} as shown in Fig. 5.
NOTE: • Insert the Second Hammer [22]{22} into the Cylinder [20]{20} without tilting so that O-
ring (B) [21]{21} is not damaged.
(2) Push the new Stopper Ring [25]{25} into the Cylinder [20]{20} and then insert the J-407 stopper ring jig
into the Cylinder [20]{20} as shown in Fig. 5.
NOTE: • The Stopper Ring [25]{25} has a white mark to differentiate from the Stopper Ring [3]{3}.
• Push the new Stopper Ring [25]{25} into the Cylinder [20]{20} with the break of the
Stopper Ring [25]{25} facing away from the 4-mm dia. hole on the Cylinder[20]{20} as
shown in Fig. 5. If the ring break is faced toward the 4-mm dia. hole, it may be hard to
disassemble the cylinder ass’y.
(3) Use a hand press to press against the upper end of the J-407 stopper ring jig until the Stopper Ring
[25]{25} is fitted into the bore groove of the Cylinder [20]{20}.
NOTE: Check that the Stopper Ring [25]{25} is fitted securely into the bore groove of the Cylinder
[20]{20} through the two 4-mm dia. holes on the periphery of the Cylinder [20]{20}.
Reassembly
Hand press
J-407 stopper ring jig
Break of [25]{25}
Special repair tool Code No.
J-407 Stopper ring jig 376747
[25]{25}
[22]{22}
[21]{21}
4-mm dia. hole
[23]{23}
[24]{24}
Bore groove of [20]{20}
[23]{23}
[20]{20}
4-mm dia. hole
4-mm dia. hole
4-mm dia. hole
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-5-
Fig. 6 • Reassembly of the gear cover and cylinder ass’y
2. Reassembly of the gear cover and cylinder ass’y
(1) Mount the Second Gear [18]{18}, Spring (A) [17]{17}, and Washer [16]{16} on the Cylinder [20]{20}
ass’y and fix them with the Retaining Ring for D25 Shaft [15]{15}. Mount the Damper [26]{26}, Thrust
Washer (A) [27]{27}, and Thrust Washer (B) [28]{28} from the rear end of the Cylinder [20]{20}. Then,
push this ass’y into the Gear Cover [9]{9} as far as it will go.
NOTE: Be sure to mount the parts in the correct order as shown in Fig. 6.
(2) Mount the O-ring [12]{12} to the Change Lever [11]{11} and put it in the hole on the Gear Cover [9]{9}.
Insert the Stopper [13]{13} into the groove inside the Change Lever [11]{11}. Then, push the Change
Lever [11]{11} in the hole of the Gear Cover [9]{9} as far as it will go.
NOTE: Push the Change Lever [11]{11} in the Gear Cover [9]{9} without tilting so that the O-ring
[12]{12} is not twisted.
(3) Set the Change Lever [11]{11} to the "Rotation + Hammering" ( mark) position. Tighten the Machine
Screw M4 x 5 [14]{14} to fix the Change Lever [11]{11} to the Gear Cover [9]{9}.
(4) Mount the Holder Spring [7]{7}, Holder Plate [6]{6}, and Steel Ball D7.0 [19]{19} to the tip of the Cylinder
[20]{20}. Mount the Ball Holder [5]{5} to the Grip [4]{4} and mount it to the Cylinder [20]{20}. Then,
mount the Stopper Ring [3]{3} and Front Cap [2]{2} to the Cylinder [20]{20}.
[27]{27}
[28]{28} [26]{26}
[17]{17}
[16]{16}
[15]{15}
[18]{18}
[11]{11}
[13]{13}
[14]{14}
[7]{7} [6]{6}
[5]{5}
[5]{5}
[3]{3}
[4]{4}
[2]{2}
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-6-
Fig. 7 • Reassembly of the second shaft ass’y (1)
Fig. 8 • Reassembly of the second shaft ass’y (2)
3. Reassembly of the second shaft ass’y
NOTE: Use the special repair tool specified in the
table for reassembly of the second shaft
ass’y.
(1) Mount the Clutch [44]{44}, Reciprocating Bearing [45]{45}, Needle Cage [46]{46}, and Thrust Washer
(C) [47]{47} on Second Shaft (A) [43]{43}. Then, mount the Bevel Gear [48]{48} and the J-408 bevel
gear jig on Second Shaft (A) [43]{43} as shown in Fig. 7. Push Second Shaft (A) [43]{43} with a hand
press until the end of Second Shaft (A) [43]{43} contacts the end of the J-408 bevel gear jig. Then,
remove the J-408 bevel gear jig and mount it in reverse direction as shown in Fig. 8 and push Second
Shaft (A) [43]{43} with a hand press until the end of Second Shaft (A) [43]{43} contacts the end of the
J-408 bevel gear jig.
NOTE: After reassembly of the second shaft ass’y, check the following.
• Check that the Reciprocating Bearing [45]{45} rotates around Second Shaft (A) [43]{43}
smoothly.
• Check that the Reciprocating Bearing [45]{45} has an appropriate clearance by moving
it back and forth.
Special repair tool Code No.
J-408 Bevel gear jig 376748
J-408 bevel gear jig
[47]{47}
[45]{45}
[48]{48}
[44]{44}
[46]{46}
End of [43]{43}
Hand press
J-408 bevel gear jig
End of [43]{43}
Hand press
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-7-
Fig. 9 • Reassembly of the hammering mechanism
4. Reassembly of the hammering mechanism
NOTE: Degrease the M5 screw hole on Inner Cover (A) Ass’y [49]{49} using the parts cleaner before
reassembly of the hammering mechanism. Otherwise, the screw may be loosened and it may
cause troubles.
(1) Mount O-ring (A) [30]{30} to the Striker [29]{29} and push it in the Piston [31]{31} as shown in Fig. 9.
Mount the two Washers [42]{42} to the Piston [31]{31} and insert the Piston Pin [41]{41} into the Piston
[31]{31}.
(2) Mount O-ring (A) [36]{36} to Inner Cover (A) Ass’y [49]{49}. Put 6 grams of grease for rotary hammer in
the cylinder of Inner Cover (A) Ass’y [49]{49}.
(3) Insert the arm of the Reciprocating Bearing [45]{45} of the second shaft ass’y into the Piston [31]{31}
so that the arm of the Reciprocating Bearing [45]{45} is sandwiched between the two Washers [42]{42}
as shown in Fig. 9. Insert the rear end of Second Shaft (A) [43]{43} into Inner Cover (A) Ass’y [49]{49}.
(4) Allow the inner ring of the Reciprocating Bearing [45]{45} to make one rotation and check that the Piston
[31]{31} makes one reciprocation. Pull the Piston [31]{31} to check that it does not come off.
(5) Fit Inner Cover (B) [35]{35} in Inner Cover (A) Ass’y [49]{49} and tighten the two Seal Lock Hex. Socket
Hd. Bolts M5 x 14 [34]{34}.
Arm of [45]{45}
Put 6 grams of grease
for rotary hammer in it.
[49]{49}
[36]{36}
[30]{30} [31]{31}
[29]{29}
[34]{34}
[42]{42}
[35]{35}
[41]{41}
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-8-
Fig. 10 • Reassembly of the gear cover ass’y
5. Reassembly of the gear cover ass’y
(1) After mounting the hammering mechanism to Inner Cover (A) Ass’y [49]{49}, insert Spring (B) [33]{33}
into the tip of Inner Cover (B) [35]{35}. Mount the Thrust Plate [32]{32} to the Piston [31]{31} fitting its
bottom in the outside groove on the Clutch [44]{44}. At this time, mount the Thrust Plate [32]{32} so that
its notch is aligned with the Change Lever [11]{11} receiving portion of Inner Cover (A) Ass’y [49]{49}.
(2) Check that Thrust Washer (A) [27]{27} and Thrust Washer (B) [28]{28} are mounted to the rear of the
Cylinder [20]{20} in the Gear Cover [9]{9}. Put 15 grams of grease for rotary hammer in the Gear Cover
[9]{9}.
NOTE: When putting grease for rotary hammer in the Gear Cover [9]{9}, do not put grease in the
Cylinder [20]{20}. Do not apply grease to the 13-mm dia. shaft of the Change Lever [11]{11}
and Machine Screw M4 x 5 [14]{14}.
(3) Set the Change Lever [11]{11} on the Gear Cover [9]{9} to the “Rotation + Hammering” ( mark)
position. Press the Gear Cover [9]{9} against Housing (A).(B) Set [63]{63} so that they are properly
mounted. At this time, check that the Piston [31]{31} is inserted into the Cylinder [20]{20}.
NOTE: • Be careful not to get O-ring (A) [36]{36} caught between the Gear Cover [9]{9} and
Housing (A).(B) Set [63]{63}.
• If the Gear Cover [9]{9} cannot be mounted to Housing (A).(B) Set [63]{63} due to
improper engagement between the Second Gear [18]{18} and Second Shaft (A) [43]{43},
insert the SDS-plus shank into the Cylinder [20]{20} and turn the Cylinder [20]{20} to
properly engage the Second Gear [18]{18} with Second Shaft (A) [43]{43}.
[27]{27}
[28]{28}
Put 15 grams of grease
for rotary hammer in it.
[44]{44}
[20]{20}
[9]{9}
[32]{32}
[35]{35}
[33]{33}
[31]{31}
[63]{63}
[36]{36}
[49]{49}
[32]{32}
Change Lever [11]{11}
receiving portion
Notch
[49]{49}
13-mm dia. shaft of [11]{11}
[14]{14}
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-9-
Fig. 11
Fig. 12
Fig. 13
6. Wiring of the wiring ass’y
(1) Insert the connector cable into the connector of the DC-Speed Control Switch [61]{61} until it is securely
locked.
(2) Apply grease for cordless rotary hammer to the Wiring [65]{64} as specified in Fig. 12.
CAUTION: The grease for cordless rotary hammer is a special grease having conducting
properties. Do not apply any grease other than the grease for rotary hammer to the
battery terminals. Otherwise, it may cause a malfunction or accident.
(3) Put the panel ass’y in housing (A) so that the internal wires between the panel ass’y and the main PCB
ass’y are positioned as shown in Fig. 13.
NOTE: Align the internal wires between the panel ass’y and the main PCB ass’y horizontally to
prevent disconnection.
[61]{61}
Connector
Connector cable
Insert the connector cable
securely until it is locked.
Battery terminal
(Model DH 18DPA: 3 places)
Model DH 12DD
Outside of the cable sleeve (2 places)
Model DH 18DPA
Battery terminal
(Model DH 12DD: 4 places)
Panel ass’y
Internal wires
Housing (A)
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