Renishaw APCA 45, Installation And User Manual

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13
Pneumatic set-up
Introduction
The APC is a pneumatically operated probe cover
that is available in two main configurations:
• APCA where pressure is required for both
extending and retracting the cover.
• APCS where pressure is required for
extending the cover and an internal spring
retracts the cover.
“Air bleed” configuration
Both APCA and APCS can be configured to
provide an “air bleed” function. “Air bleed” is where
air flows at a constant rate over the stylus cube
when the APC cover is extended or retracted to
help prevent build-up of contamination on the
stylus cube and within the mechanism.
“Air bleed” is recommended when the cover is
extended and the machine tool is cutting.
It is also recommended to activate “air bleed”
momentarily when the cover is retracted prior to
measurement.
A flow control valve can be fitted to regulate the
“air bleed”.
NOTES:
“Air bleed” is not guaranteed to remove all debris.
This is dependent on the application and the
environment.
“Air bleed” is created when a pressure limited seal
is activated by the control circuit. This will occur
when pressure is applied to Port 1 when the cover
is fully retracted, or when pressure is applied to
Port 1 when the cover is extended and held with a
pressure greater than 4.5 bar (65.3 psi) on Port 3.