Hitachi DS 12DM Manual

TECHNICAL DATA
AND
SERVICE MANUAL
CORDLESS DRIVER DRILL
DS 12DM
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
LIST No. F894 Nov. 2003
D
MODEL
DS 12DM
Hitachi 
Power Tools

REMARK:
Throughout this TECHNICAL DATA AND SERVICE MANUAL, a symbol(s)
is(are) used in the place of company name(s) and model name(s) of our
competitor(s). The symbol(s) utilized here is(are) as follows:
Symbols Utilized Competitors
Company Name Model Name
BOSCH GSR12VE-2
B
MAKITA 6317D
C

Page
CONTENTS
1. PRODUCT NAME.............................................................................................................................. 1
2. MARKETING OBJECTIVE ................................................................................................................ 1
3. APPLICATIONS................................................................................................................................. 1
4. SELLING POINTS ............................................................................................................................. 1
4-1. Selling Point Descriptions ...................................................................................................................2
5. SPECIFICATIONS ............................................................................................................................. 5
6. COMPARISONS WITH SIMILAR PRODUCTS ................................................................................. 6
7. WORKING PERFORMANCE PER SINGLE CHARGE..................................................................... 7
8. PRECAUTIONS IN SALES PROMOTION ........................................................................................ 8
8-1. Safety Instructions ..............................................................................................................................8
8-2. Inherent Drawbacks of Cordless Driver Drills Requiring Particular Attention
During Sales Promotion ....................................................................................................................10
9. REFERENCE MATERIALS ............................................................................................................. 12
9-1. Feedback System .............................................................................................................................12
10. REPAIR GUIDE ............................................................................................................................. 13
10-1. Precautions in Disassembly and Reassembly................................................................................13
10-2. Precautions in Disassembly and Reassembly of Battery Charger .................................................21
11. STANDARD REPAIR TIME (UNIT) SCHEDULES......................................................................... 22
Assembly Diagram for DS 12DM

--- 1 ---
1. PRODUCT NAME
Hitachi 12 V Cordless Driver Drill, Model DS 12DM
2. MARKETING OBJECTIVE
The new Model DS 12DM is a compact and lightweight cordless driver drill that was developed to reinforce our
12-V product range including the well-reputed Model DS 12DVB. Thanks to the high-power rare-earth magnet
motor, the Model DS 12DM is as powerful as the bigger drills with the maximum torque 36 N•m {367 kgf•cm} while
it is compact (entire length 203 mm) and lightweight (1.7 kg). The Model DS 12DM provides improved
performance as it was developed under the concept for a higher-power, easier-to-operate and easier-to-maintain
cordless driver drill.
3. APPLICATIONS
Tightening and loosening wood screw, self-tapping screw and machine screw
Drilling into wood materials, plastic, mild steel and aluminum
4. SELLING POINTS
Compact and high power
It is as powerful as the bigger drills while it is compact and lightweight.
203 mm in entire length, 1.7 kg in weight and 36 N•m {367 kgf•cm} of
maximum torque
Easier to operate
Slip-resistant clutch dial
•It is soft and easy to turn
thanks to the elastomer resin.
Comfortably shaped handle
•It is soft and slip-resistant
thanks to the elastomer resin.
•Slim handle
One-touch hook
•Ready for use at anytime
(angle-adjustable in 5 steps)
•Mountable on either side
•Convenient bit holder
Flat battery
•Compact and stable
•Interchangeable with
conventional batteries
All new design
The cyber design descended from the Model WH 12DM
Higher power
Improved overload durability
(improved cooling efficiency)
•Large radial fan
•Optimally designed cooling
air path
22-stage clutch
•Fine torque adjustment
Keyless chuck is operable with
one hand and equipped with
locking mechanism
•Prevents the driver bit from
loosening.
•Operable with one hand
Manual tightening mechanism
•Usable as a manual
screwdriver
Easier to maintain
Externally replaceable carbon brushes
•The carbon brushes are singly
replaceable.
Separate-type motor
•The armature is singly replaceable.

--- 2 ---
4-1. Selling Point Descriptions
4-1-1. Compact, high power and all new design
Thanks to the high-power rare-earth magnet motor, the Model DS 12DM is as powerful as the bigger drills with the
maximum torque 36 N•m {367 kgf•cm} while it is compact (entire length 203 mm) and lightweight (1.7 kg) (see
Table 1). Besides, the Model DS 12DM is of a cyber design descended from the Model WH 12DM.
Table 1
4-1-2. Improved overload durability (improved cooling efficiency)
The Model DS 12DM is equipped with the separate-type motor that is the same as a driver drill with a power cord.
To improve the overload durability in continuous operation, the optimally designed cooling air path that is
descended from the Model WH 12DM increases the cooling efficiency as well as the large radial fan increases the
volume of air (see Fig. 1).
Fig. 1 Curves of motor temperature rise
L Entire length [mm]
H Entire height [mm]
W Entire width [mm]
Weight [kg]
Maximum torque [N•m]
DS 12DM
203
229
73
1.7
36 (367 kgf•cm)
DS 12DVB
242
234
73
1.9
36 (367 kgf•cm)
C
243
243
94
2.0
35 (357 kgf•cm)
B
256
260
86
2.2
Not indicated
DS 12DM C
B
Temperature rise outside the motor (K)
1.5 N•m {15 kgf•cm} intermittent load test [20 cycles/minute operation]
Cycle (time)
: Saturated (no abnormality)
: Burnt

--- 3 ---
0.49 N•m {5 kgf•cm}
0.98 N•m {10 kgf•cm}
1.96 N•m {20 kgf•cm}
2.94 N•m {30 kgf•cm}
3.92 N•m {40 kgf•cm}
4.40 N•m {45 kgf•cm}
4-1-3. 22-stage clutch and slip-resistant clutch dial
The 22-stage clutch ensures fine torque adjustment. The clutch dial is made of elastomer resin (soft resin). It is
soft and slip-resistant, and easy to change the torque.
4-1-4. Manual tightening mechanism
The Model DS 12DM can be used as a manual screwdriver. When a screw cannot be driven completely by the
operation with the clutch dial setting, flip off the switch and turn the main body by hand to drive the screw
completely (maximum manual tightening torque: 22.5 N•m {230 kgf•cm}).
4-1-5. Keyless chuck is operable with one hand and equipped with locking mechanism
The sleeve can be turned with one hand. The driver bits can be easily replaced by holding the main unit with one
hand while turning the sleeve with the other hand. The Model DS 12DM is also equipped with the locking
mechanism to prevent the sleeve from loosening during operation. A simple twist until a click is heard locks the
sleeve tight.
Elastomer resin
(soft resin)
Table 2. Guide for selection of tightening torque
* There may be difference in operation depending on the screw
shapes and workpieces. Perform a test before actual driving.
1
4 (indicated with " ")
9
14 (indicated with " ")
19
22
Tightening torque
Clutch dial position
Sleeve

--- 4 ---
4-1-6. Comfortably shaped handle
The handle grip is soft and slip-resistant thanks to the elastomer (soft resin). In addition, the handle shape is
improved so that it comfortably fits in a hand.
4-1-7. One-touch hook
The hook can be quickly slid out whenever necessary and slid in when not necessary.
The hook is mountable on either side using a flat-blade screwdriver or a coin.
The angle of the hook is adjustable in five steps.
The hook can hold a 65-mm double-ended bit. It is very convenient for holding a spare bit.
4-1-8. Externally replaceable carbon brushes and separate-type motor
The carbon brushes are replaceable from the outside. In addition, the armature is singly replaceable thanks to
the adoption of the separate-type motor that is the same as a driver drill with a power cord. Thus the Model
DS 12DM is easier to maintain.
4-1-9. Flat battery
The battery is flat enough to stand the Model DS 12DM upright stably. The conventional Hitachi 12-V batteries
are also usable.
Armature
Magnet
Carbon brush
DS 12DM
Gently shaped handle
comfortably fits in a hand.
Conventional model
Elastomer
(soft resin)
1
2
3
4
A bit can be held.
Slide out.
Mountable on either sideAngle-adjustable in 5 steps
Case-type motor (carbon brushes are built in)
[Conventional model]
Separate-type motor [Model DS 12DM]

--- 5 ---
Main body (including battery) •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1.7 kg (3.7 Ibs.)
Charger unit (including cord) ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 0.6 kg (1.3 Ibs.)
Gross with charger and case •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 4.7 kg (10.4 Ibs.)
Screwdriver Machine screw ••••••••6 mm (1/4")
Wood screw ••••••••••••6.8 dia. x 50 mm (#16 x 2")
Drill Metal ••••••Mild steel 13 mm (1/2") [Thickness 1.6 mm (1/16")]
Aluminum 13 mm (1/2") [Thickness 1.6 mm (1/16")]
Wood••••••••••••••••••••••27 mm (1-1/16") [Thickness 18 mm (11/16")]
Mount type ••••••Screw-on (UNF 1/2" --- 20)
Diameter •••••••••1.5 --- 13 mm (1/16" --- 1/2")
Low: 0 --- 350/min High: 0 --- 1,200/min
Slip torque •••••••• 0.5 --- 4.4 N•m (5 --- 45 kgf•cm, 4.3 --- 39 in-lbs.) [22 stages]
Max. torque ••••••• Low: 36 N•m (367 kgf•cm, 319 in-lbs.)/High: 9 N•m (92 kgf•cm, 80 in-lbs.)
Fan cooled rare-earth magnet motor
Trigger switch with pushing button for forward and reverse rotation changeover (with brake)
T-type
Body ••••••••••• Glassfiber reinforced polyamide resin (green)
and thermoplastic elastomer (gray)
Battery •••••••• ABS resin (black)
Charger •••••• ABS resin (black)
Sealed cylindrical nickel-cadmium battery
Nominal voltage ••••••••••••••• DC 12 V
Nominal life ••••••••••••••••••••• Charging/discharging: approximately 1,000 times
Nominal Capacity •••••••••••••2.0 Ah
Sealed cylindrical nickel-metal hydride battery
Nominal voltage ••••••••••••••• DC 12 V
Nominal life ••••••••••••••••••••• Charging/discharging: approximately 500 times
Nominal Capacity ••••••••••••• 3.0 Ah
Overcharge protection system: (1) Battery voltage detection ( 2V system)
(2) Battery surface temperature detection
(thermostat or thermistor)
(3) 120-minute timer
Power input: 56 W
Charging time: Approx. 50 minutes [for type EB 1220BL battery at 20˚C (68˚F)]
Approx. 70 minutes [for type EB 1230HL battery at 20˚C (68˚F)]
Operable ambient temperature range: 0 ˚C --- 40˚C (32˚F --- 104˚F)
The maximum allowable temperature of the type EB 1220BL battery is 60˚C (140˚F) and
the type EB 1230HL battery is 45˚C (113˚F).
Indication method of battery charging function:
5. SPECIFICATIONS
Capacity
Keyless chuck
(13VLRG-N)
Rotation speed (No-load)
Type of motor
Torque
Type of switch
Handle configuration
Enclosure
Battery
(Type EB 1220BL)
Charger
(Model UC 14YFA)
Weight
Standard accessories
Battery
(Type EB 1230HL)
Charger •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Extra battery •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Phillips (plus) driver bit (No. 2) ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Case •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1

--- 6 ---
6. COMPARISONS WITH SIMILAR PRODUCTS
Maker
Model name
Max. capacity
Screw
driving
Drilling
Rotation
speed Low
High
Slip torque
Max. torque
HITACHI
DS 12DM
0 to 350/min
0 to 1,200/min 1.0 to 5.9 N•m
10 to 60 kgf•cm
(8.7 to 52 in-lbs.)
[22 positions]
36 N•m
367 kgf•cm
(319 in-lbs.)
0 to 350/min
0 to 1,300/min
0.5 to 4.4 N•m
5 to 45 kgf•cm
(4.3 to 39 in-lbs.)
[22 positions] 36 N•m
367 kgf•cm
(319 in-lbs.)
DS 12DVB C
0 to 400/min
0 to 1,300/min
Not indicated
35 N•m
357 kgf•cm
(310 in-lbs.)
B
0 to 400/min
0 to 1,400/min
Feedback circuit
Switch
Dimensions
Equipped
Equipped
203 mm (8")
Remarks* •••••••• Charging time may vary depending on charger to be used.
Equipped
Equipped
242 mm (9-17/32")
Not indicated
Equipped
243 mm (9-9/16")
Not indicated
Equipped
256 mm (10-5/64")
Electric brake
Weight 1.7 kg
(3.7 lbs.) 1.9 kg (4.2 lbs.) 2.0 kg (4.4 lbs.) 2.2 kg (4.9 lbs.)
Overall length
Overall height 229 mm (9") 234 mm (9-13/64") 243 mm (9-9/16")
260 mm (10-15/64")
[16 positions]
Mild steel
Aluminum
Wood
13 mm (1/2")
13 mm (1/2")
27 mm (1-1/16")
13 mm (1/2")
13 mm (1/2")
32 mm (1-1/4")
13 mm (1/2")
13 mm (1/2")
25.4 mm (1")
13 mm (1/2")
13 mm (1/2")
32 mm (1-1/4")
Machine screw
Wood screw
6 mm (1/4" dia.)
8 dia. x 38
(#20 x 1-1/2")
6 mm (1/4" dia.)
6.8 dia. x 50
(#16 x 2")
Not indicated Not indicated
8 dia. x ---
(#20 x ---)
6 dia. x 75
(1/4 x 3")
2.0 to 10 N•m
20 to 102 kgf•cm
(17.7 to 89 in-lbs.)
[15 positions]
Not indicated
Equipped Equipped Equipped Equipped
Locking device
Drill chuck
Single sleeve Single sleeve Double sleeve Single sleeve
Type
13 mm (1/2") 13 mm (1/2") 13 mm (1/2") 13 mm (1/2")
Capacity
Battery
Charging time* 50 min. 70 min. 60 min. 60 min.
Type Variable speed Variable speedVariable speed Variable speed
Automatic spindle lock
Reversing switch
Equipped
Push-button
Equipped
Push-button
None
Push-button
Equipped
Push-button
Rare-earth magnet
Replaceable armature
Equipped
Equipped
None
None
None
Equipped
None
None
Replaceable carbon brushes
Handle shape
Equipped
T-type
None
T-type
Equipped
T-type
Equipped
T-type
Soft grip handle Equipped Equipped Equipped Equipped
Clutch dial with elastomer resin
Strap
Equipped
Equipped
None
Equipped
None
None
None
None
Belt hook Equipped None None None
Nominal capacity 2.0 Ah 3.0 Ah 2.0 Ah 3.0 Ah 2.6 Ah 2.4 Ah
Nominal voltage 12 V 12 V 12 V 12 V
50 min. 70 min.
Overall width 73 mm (2-7/8") 73 mm (2-7/8") 94 mm (3-45/64") 86 mm (3-13/32")
○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○○

--- 7 ---
Test condition Maker Model name
No. of drilling or fastening operations per charge (*1)
Working
time
(sec./pc.)
0*400
100 *800 200 *1200
300
"High speed"
5.7
6.6
5.4
6.4
140 (93)
135 (90)
96
105
DS 12DM
HITACHI
C
B
DS 12DVB
DS 12DM
HITACHI
C
B
DS 12DVB
1.2
1.3
1.3
1.3
5.7
5.9
5.5
5.8
290 (193)
305 (203)
240
260
110 (73)
115 (77)
95
105
DS 12DM
HITACHI
C
B
DS 12DVB
DS 12DM
HITACHI
C
B
DS 12DVB
880 (587)
750 (500)
530
660
0.6
0.7
0.7
0.7
"High speed"
"High speed"
"Low speed"
7. WORKING PERFORMANCE PER SINGLE CHARGE
Drilling and fastening performance comparison per charge
Remarks* Number of machine screws fastened per charge
Remarks*1 Number of holes or fasteners per charge
The above table shows an example of test data. The batteries used in this test data are as follows:
Models DS 12DM and DS 12DVB: 3.0 Ah
C: 2.6 Ah
B: 2.4 Ah
Figures in parentheses ( ) indicate the values for a 2.0 Ah battery.
As actually measured values listed in the above table may vary depending on sharpness of drill bit, workpiece
hardness (particularly in wood materials), moisture content of wood, charging condition, operator skill, etc. This
data should be used as a comparative guide only.