Maintenance And Inspection - Hitachi P 20SB Handling Instructions Manual

(2) As shown in Fig. 5, slide the rear side of the cutter blade
in the direction indicated by the arrow to disassemble the
cutter blade.
CAUTIONS
○ Be careful not to injure your hands.
○ It is not necessary to disassemble the back metal from
the cutter blade. (See Fig. 6)
○ Disassembling the back metal from the cutter blade is to
be made only at grinding the cutter blade.
2. Cutter blade assembly
CAUTION
○ Prior to assembly, thoroughly wipe off all swarf
accumulated on the cutter blade.
(1) Turn the cutter block fl at surface sideways, and assemble
the adjusted cutter blade as shown in Fig. 7. Ensuring
that the leaf spring on the cutter block is correctly fi tted
to the hole on the rear plate, push the back of the cutter
blade with a fi ngertip in the direction indicated by the
arrow, until the edge of the back metal is properly fi tted to
the cutter block surface. Correct installation is illustrated
in Fig. 8.
(2) Place the blade holder on the completed assembly,
as shown in Fig. 10, and fasten it with the three bolts.
Ensure that the bolts are securely tightened.
(3) Turn the cutter block over, and set the other side in the
same manner.
3. Adjustment of cutter blade height
CAUTION
○ As the set gauge has been accurately factory adjusted,
never attempt to loosen it.
(1) After attaching the back metal to the cutter blade,
temporarily fasten them together with machine screws,
as shown in Fig. 11.
(2) Insert the set gauge plate spring into the hole on the back
metal and heavily push the plate spring in the direction
indicated by the arrow in Fig. 12 until it snaps into the
correct position.
(3) Holding the set gauge with the blade edge facing
downward as shown in Fig. 13, loosen the temporarily
fastened machine screws and lightly push the cutter
blade with a thumb until the cutter blade gently touches
plate.
CAUTION
○ Do not push the blade with excessive pressure.
Excessive pressure could cause maladjustment of the
blade height.
(4) Finally, retighten the machine screws to securely fasten
the cutter blade and the back metal, thereby completing
the blade height adjustment procedure.
(5) Holding the set gauge as shown in Fig. 14, push upward
on the back metal and remove it from the set gauge.
(6) The cutter blade is now ready to be mounted on the planer
as described in the section on cutter blade assembly.
CARBIDE BLADE ASSEMBLY AND
DISASSEMBLY AND ADJUSTMENT OF CUTTER
BLADE HEIGHT (FOR DOUBLE EDGED BLADE
TYPE)
1. Carbide blade disassembly
(1) As shown in Fig. 15, loosen the blade holder with the
attached box wrench.
(2) As shown in Fig. 16, remove the carbide blade by sliding
it with the attached box wrench.
CAUTION
○ Be careful not to injure your hands.
2. Carbide blade assembly
CAUTION
○ Prior to assembly, thoroughly wipe off all swarf
accumulated on the carbide blade.
(1) As shown in Fig. 17, lift set plate (B) and insert the new
carbide blade between cutter block and set plate (B).
(2) As shown in Fig. 18, mount the new carbide blade by
sliding it on the set plate (B) so that the blade tip projects
by 1mm from the end of the cutter block.
(3) As shown in Fig. 19, fi x the bolts at the blade holder after
blade replacement has been completed.
(4) Turn the cutter block over, and set the other side in the
same manner.
3. Adjustment of carbide blade height
CAUTION
○ If the carbide blade's heights are inaccurate after
above procedures have been completed, carry out the
procedures described below.
(1) As shown in Fig. 4, use the box wrench to loosen the
three bolts used to retain the carbide blade, and remove
the blade holder.
(2) As shown in Fig. 20, after removing the carbide blade,
slide set plate (B) in the direction indicated by the arrow
to disassemble set plate (B).
(3) Loosen the 2 screws holding on the carbide blade and
set plate (A), set plate (B).
(4) As shown in Fig. 21, 22, press the turned surface of
set plate (A) to the wall surface (B) while adjusting the
carbide blade edge to the wall surface a of the set gauge.
Then, tighten them with the 2 screws.
(5) As shown in Fig. 23, 24, insert a turned portion of set
plate (A) attached to set plate (B) into a groove on the fl at
portion of the cutter block.
(6) As shown in Fig. 25, place the blade holder on the
completed assembly and fasten it with the three bolts.
Ensure that the bolts are securely tightened. Follow the
same procedures for the opposite side carbide blade.
SHARPENING THE RESHARPENABLE CUTTER
BLADES
Use of the optional accessory Blade Sharpening Ass'y is
recommended for convenience.
1. Use of Blade Sharpening Ass'y
As shown in Fig. 26, two blades can be mounted on
the blade sharpening ass'y to ensure that the blade tips
are ground at uniform angles. During grinding, adjust
the position of the cutter blades so that their edges
simultaneously contact the dressing stone as shown in
Fig. 27.
2. Cutter blade sharpening intervals
Cutter blade sharpening intervals depend on the type
of wood being cut and the cutting depth. However,
sharpening should generally be eff ected after each 500
meters of cutting operation.
3. Grinding allowance of the cutter blades
As illustrated in Fig. 28, a grinding allowance of 3.5 mm
is provided for on the cutter blade. That is , the cutter
blade can be repeatedly sharpened until its total height
is reduced to 24.5 mm.
4. Dressing stone
When a water dressing stone is available, use it after
dipping it suffi ciently in water since such a dressing stone
may be worn during grinding works, fl atten the upper
surface of the dressing stone as often as necessary.

MAINTENANCE AND INSPECTION

1. Inspecting the blades
Continued use of dull or damaged cutter blades will result
in reduced cutting effi ciency and may cause overloading
of the motor. Sharpen or replace the cutter blades as
often as necessary.
English
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