System Description - Renishaw ACR2 Guia De Instalacion

INTRODUCTION

1.2 System description

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The ACR2 rack consists of pairs of ports that store arms. The arms are
either head adapters (HA) or head extensions (HE).
The ports allow arms stored in them to be automatically locked and unlocked
onto a PHS1 servo positioning head.
To change probe arms automatically, the CMM must be programmed to
complete a series of movements using positions calculated during the port
datum routine. These movements cause a mechanism inside the port to
rotate a screwdriver which engages a slot on the arm. The slot activates a
cam which, when rotated, locks the arm in place.
Manual fitment of probe arms can be achieved using the S10 autojoint key
supplied.
Arms are located in the rack port on two steel pins which pass through holes
in the arm. A spring-loaded lid secures the arm in position and seals the
spring-loaded electrical contacts and kinematic locations against
contamination.
Signals to indicate when an arm is present on the head and whether the arm
is locked correctly and safely are provided by the servo positioning head.
This ensures that arms are always positively locked on the head.
Crash protection is provided by the head overtravel unit. Any machine move
errors or mis-programmed moves which cause an unexpected collision will
cause the head overtravel to operate, sending a signal to stop the machine.
The maximum operating speed of the ACR2 autochange rack should not
exceed 100mm/sec.
NOTE
Manual No. H-1000-4045