DEK高级培训资料.pdf - 第140页
Linear Encoder Theory • The optical read head measures positional information from the encode r strip running the length of the permanent magnet track • Two pul se trains allow direction and velocity to be calculated Iss…
•
A EuroFlex card supplies power sequentially to the three phase windings in the
Forcer. The windings are physically 120 degrees out of phase.
•
Magnetic attraction between the in-phase winding and the permanent magnetic
poles in the magnet track causes the forcer to move.
•
The 3 Hall Effect switches are used during start up to establish the position of
the forcer relative to the N-S magnets.Their outputs are used by the EuroFlex
drive cards to establish the initial current levels and polarity to be supplied to
Linear Motors Theory
Issue 2: July 2007
drive cards to establish the initial current levels and polarity to be supplied to
the forcer. Once speed and direction is established motion detection passes
over to the encoder.
Linear Encoder Theory
•
The optical read head measures positional information
from the encoder strip running the length of the permanent
magnet track
•
Two pulse trains allow direction and velocity to be
calculated
Issue 2: July 2007
Linear Motor Components
Permanent Magnet Track
Camera
Home
sensor
Issue 2: July 2007
Forcer
Read Head
Encoder
strip
‘index’ Sensor
used on early
machines. No
longer fitted.