HOWA MACHINERY H3EF, Инструкция по эксплуатации, Страница: 39 / 52

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To obtain better accuracy, use the forming plug shown in Fig.4 Table.7. This plug can be
detached without removing the top jaws.
Table6
Chuck size 6 8
S1
+0.2
0
(mm) 58 80
S4 (mm) 22 32
S6 M8 M8
Fig.13
Remark: In case that the forming procedure is done using the stoppers designed
by customer, determine the dimension s4 considering the height of
stoppers.
Table7
Chuck size 6 8
S1
+0.2
0
(mm) 58 80
S2 (mm) 49 64
S3 (mm) 35 45
S4 (mm) 22 32
S5 (mm) 10 18
Fig.14
S6 M8 M8
Fig.12
１ １ １ １
●
Prepare a plug for forming the top jaws.
・
In case using the standard top jaws, determine
φ
d of a forming plug referring Fig.13
and Table6.
・ φ
d is determined as to be that the clamping jaw stroke is the middle of full jaw stroke.
・
The finish of
φ
d part is to be around
▽▽▽
. Forming plug should have enough rigidity
to avoid the deformation by the clamping force.
・
Make a screw at the center of the forming plug to insert a bolt as a handle.
This bolt must be long enough to work as a handle when gripping the forming plug so
that the operator does not catch his/her hand in it.
２ ２ ２ ２
●
Clamp the forming plug.
・
Remove the stopper and top jaws if those are installed.
・
Put the forming plug on the front face of the chuck, and then install the top jaws with
lighter fastening torque.
・
Clamp the forming plug with lower pressure operating the hydraulic circuit.(Approx.
0.5MPa)
Note: In case that installing the top jaws or clamping pressure is inappropriate, forming
plug may rise up, causing inferior accuracy.
・
Press the forming plug against the front face of the chuck, and then grip it preventing the
inclination of plug.
・
In this condition, fasten the top jaw mounting bolts with prescribed torque.
・
Under the state of unclamping the top jaws, adjust the pressure to required value, and
then clamp the plug again.
Note: Press the forming plug against the front face of the chuck, and then grip it
preventing the inclination of plug. Inclination of plug causes inferior accuracy.
３ ３ ３ ３
●
Form
φ
d' part where the work piece is held, keeping the plug as above-mentioned.
・
Diameter
φ
d' should be formed in the same diameter as the gripping diameter of the
work piece (approx. allowance H7) and its surface finish should be better than 1.6a.
・
Minimize the cutting depth and feed to obtain the better surface when finishing.
・
Pressure for the jaw forming is to be the same as that of actual operation.
４ ４ ４ ４
●
After finished forming of top jaws, grip the work piece in jaws and check that required jaw
stroke and gripping accuracy are obtained.
・
After finishing the forming procedure, remove the top jaws before detaching the forming
plug.
・
Install the stopper, and then mount the formed top jaws.
・
Like the procedure of clamping the forming plug, top jaw is mounted with lighter torque
and clamp the work piece with lower pressure to fasten the jaw mounting bolts with
prescribed torque.
・
Try the test cut to ensure the accuracy and no slippage.
Use care not to pinch your hand when gripping
the formed plug, or you will suffer injury to your
hand.
CAUTION