Hitachi DH 50MB Technical Data And Service Manual page 23

Handle and side handle
The handle section is of a two-layer structure consisting of a molded plastic base reinforced with glassfiber and
a soft plastic layer molded together on the base.
The side handle is also constructed of two layers consisting of a reinforced plastic base molded together with
steel nut and soft plastic surrounding the base.
This newly designed handle and side-handle structure ensure a lower vibration and a better, more comfortable
grip for a improved operability.
Front cap
Front cover
Cylinder case
Crank case
Rubber seal
Grip O-ring
Crank case cover
O-ring
Tool holder
O-ring
O-ring
Oil seal
Gear cover
Oil seal
Housing
Fig. 15
Sealing and dust-proof structure
The crank case and cylinder case section are tightly sealed with four O-rings, two oil seals and rubber seals
as shown in Fig. 15. This prevents leakage of grease from the cases, while also protecting them against dust
from the outside.
The tool holder is also protected from foreign dust by means of a rubber front cap.
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