Precision matthews PM-1440GS, Руководство пользователя

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Copyright © 2020 Quality Machine Tools, LLC PM-1440GS v3 2020-10
ENGAGING THE POWER FEED
Power feed controls are located on the apron, Figure 3-14.
The split-nut lever engages the leadscrew, and is typically
used only for screw cutting (W-X-Y knob on gear box set to
either W or Y).
The power feed lever is active only when the feed shaft is
rotating, W-X-Y knob on gear box set to X. When the lever is
pushed LEFT (cross slide) or RIGHT (saddle), the lever tip is
captive to prevent incorrect up/down movement.
When engaging power feed, move the lever gently , feeling
for the gears to mesh as you go. If the gears don’t engage at
the first try, use the appropriate handwheel to jog the saddle or
cross slide, whichever one you wish to move under power.
The split-nut lever, used only for screw cutting, cannot be
engaged unless the power feed lever is NEUTRAL, neither
up or down
FEEDSHAFT CLUTCH
The clutch shown in Figure 3-15 disengages the power feed if
the saddle or cross slide hits an obstruction when power feed-
ing, thus minimizing the potential for damage. This could be
the result of either an accidental event, or deliberately stopping
the saddle at a precise location set by the stop, Figure 3-16.
The clutch comprises a pair of spring loaded steel balls bear-
ing on a detent disc driven by the saddle feed gearbox. Spring
pressure is adjusted by two set screws on either side of the
feed shaft, arrowed in Figure 3-15. Setting the spring pressure
is a process of aiming for the best compromise between too
high — damaging feed pressure — and too low, which might
mean unexpected stopping for no good reason.
Setting the clutch to work reliably with the micrometer carriage
stop is a good example of such a compromise: start with low
spring force, then work up in small increments until the car-
riage stops in the same location (say ± 0.002”, assuming a
constant depth of cut and feed rate).
SADDLE STO P
The stop assembly, Figure 3-16, has a micrometer-style collar
graduated in 0.001 in. divisions. It can be clamped at any point
along the lathe bed (two M6 socket head screws on the under -
side secure the clamp plate to the block). Make certain that the
stop rod seats firmly on the saddle casting.
Figure 3-14 Feed control levers on apron
Saddle Power feed lever RIGHT & UP to engage. Cross-slide Lever
LEFT & DOWN to engage. Test for dis-engagement by turning the
saddle and cross-slide handwheels.
Figure 3-15 Feedshaft clutch
Figure 3-16
Micrometer saddle stop