Hitachi DS 9DVA User Manual

MODEL DS 9DVA

− 1 −

1. REPAIR GUIDE

Be sure to remove the batteries from the main body before servicing. Inadv ert ent t r iggering of t he switch
with the battery connected w ill r esult in a danger of accidental turning of the motor.

1-1. Precautions in Disassembly and Reassembly

The

[Bold]

numbers in the description below correspond to the item numbers in the parts list and exploded

assembly diagram for the Model DS 9DVA.

1-1-1. Disassembly

(1) Remove the Housing (B)

[33]

.

Remove the seven Tapping Screws (W/Flange) D3 x 16

[28]

secured to the driver unit. Gently open

the Housings (A) and (B)

[33]

while holding their battery loading sections.

(2) With the Housing (B)

[33]

removed, all the internal parts, assembled or separate, can be taken out as
they are.
Lift the entire contents from the Housing (A)

[33]

while holding the Motor

[27]

and Cap

[6]

.

(3) Remove the Drill Chuck

[2]

. (See Fig. 4.)

(a) Turn the Motor

[27]

counterclockwise (when viewed from the rear) and remove it from the Rear Case

[17]

. Remove the Shift Knob

[39]

from the Shift Arm

[18]

. Take care not to remove the Shift Arm

[18]

from the Rear Case

[17]

in this operation.

(b) Mount the motor spacer (an accessory of the Special Repair Tool J-292) to the assembly of the Drill

Chuck

[2]

, Cap

[6]

, Front Case

[11]

and Rear Case

[17]

and then mount it to the Special Repair Tool
J-292 clamped in the vise as illustrated in Fig.4. In t his oper ation, check that the pinion press-fitted
in the Special Repair Tool J-292 and the Planet Gear (A)

[23]

are engaged properly.

(c) Turn the Cap

[6]

clockwise (when viewed from the front) until it can turn no further. In this posit ion

the drill mark “

” on the Cap

[6]

is positioned to the Shift Arm

[18]

side. Secure the Slide Ring

Gear

[19]

to the Front Case

[11]

side with the Shift Arm

[18]

.

(d) Turn the sleeve of the Drill Chuck

[2]

counterclockwise (when viewed from the front) to fully open the

jaws of the Drill Chuck

[2]

. Turn the Special Screw M6 x 23

[1]

clockwise and remove it. (Note that

the Special Screw is left-hand threaded.)

(e) Fit the hexagonal bar wrench for M10 into the Drill Chuck

[2]

as illustrated in Fig. 4 and remove the

Chuck by turning the bar wrench counterclockwise.

− 2 −

Fig. 4

(4) Disassembly of the gear unit.

Remove the Shift Arm

[18]

from the Rear Case

[17]

, then remove the four Screw Sets D3 x 12

[4]

connecting the Front Case

[11]

and the Rear Case

[17]

. Remove the Washer (A)

[16]

, the Planet Gear

(C) Set

[15]

, Carrier [

14]

, Ring Gear

[13]

and Steel Ball

[12]

from the Front Case

[11]

in order. Take

care not to lose the six Steel Balls

[12]

in this operation.

(5) Disassembly of the clutch unit.

Remove the two Screw Sets D3 x 12

[4]

, then remove the Plate

[5]

, Cap

[6]

, Clutch Plate

[7]

, Spring

[8]

, Spring Holder

[9]

and Thrust Plate

[10]

.

(Note) Do not remove the Front Case

[11]

.

(6) Disassembly of the power supply unit.

(Note) Do not disconnect the three FET internal wires soldered to the DC-Speed Control Swit ch

[36]

.

Disassembly of the Motor

[27]

, DC-Speed Control Switch

[36]

, Motor Spacer

[26]

and Fin

[43]

removed
in step (3) can be carried out in the following procedure.
Disconnect the Internal Wires

[35]

and

[38]

of the Motor

[27]

with a soldering iron.

With one Bind Screw M3 x 7

[42]

removed, the FET (Field Effect Transistor) of DC-Speed Control

Switch

[36]

and the Fin

[43]

can be taken apart.

Remove the two Machine Screws M4 x 6

[30]

and take the Motor

[27]

and the Motor Spacer

[26]

apart.

When removing the Internal Wires

[35]

and

[38]

of the Motor

[27]

from the DC-Speed Control Switch

[36]

, be sure to remove the two Machine Screws M3 x 5

[34]

securing the flag-shaped terminal. (See

Fig.5.)

Rear Case

[17]

Slide Ring Gear

[19]

Drill Chuck

[2]

Special Repair Tool (J-292)

Shift Arm

[18]

Hexagonal bar wrench

Vise

Front Case

[11]

Cap

[6]

M6 x 23

[1]

Special Screw

− 3 −

1-1-2. Reassembly

Reassembly can generally be carried out as the reverse of the disassembly procedure, with some items to
be noted as follows.

(1) Reassembly of the power supply unit

(a) Be sure to perform wiring connections as indicated in the wiring diagram (Fig.5).

Fig. 5

(Note) Do not deform the bendable legs of the FET attached to the DC-Speed Control Switch

[36]

.

(b) Pay attention to the polarity of t he Mot or

[27]

when soldering the Internal Wires

[35]

and

[38]

to the

Motor

[27]

. The red marking side of the Motor

[27]

is positive. (See Fig.6.)

(Note) When installing the Motor Spacer

[26]

to the Motor

[27]

, align the negative terminal of the

Motor

[27]

with the marking on the Motor Spacer

[26]

and tighten with the Machine Screw

M4 x 6

[30]

and the Spring Washer M4

[31]

.

(c) Apply grease (Hitachi Motor Grease No.29) to the pinion pressed into the Motor

[27]

.

Fig. 6

Negative side

Marking

[26]

[27]

Red marking

Positive side

Motor Spacer

[26]

Motor

[27]

Internal Wire(Red)

[35]

DC-Speed Control Switch

[36]

Internal
Wire(Black)

[38]

Machine Screw
M4 x 6

[30]

Spring Washer M4

[31]

Machine Screw M3 x 5

[34]

Flag-shaped terminal

Terminal
Housing(B) side

Terminal
Housing(A) side

Fin

[43]

Bind Screw M3 x 7

[42] [42]

Terminal Support(A)

[41]