Namerically-controlled positioning system has been increasing in popularity and is applied to simpler and cheaper machines lately.
Then there is a demand for the simpler and cheaper NC positioning system, so the authors tried to make such a system.
The authors employed for each axis the measuring system which consists of a 5-phase synchro and two digital potentiometers instead of the multi-speed synchro system and the drive unit which consists of a induction motor and two electromagnetic disc clutches.
The 5-phase synchro has five stator windings and has the advantage of its D-A conversion being simple, in comparison with usual synchro.
This paper presents analysis of the operation of the 5-phase synchro and the static error caused by the command voltage transformer.
The output torque of the electromagnetic disc clutch can be controlled continuously by controlling the clutch current. Characteristics and heating energy losses of the clutch in such a situation is examined.
The specification of this system is following. Minimum setting unit 0.01mm, Maximum length of travel 999.99mm, Maximum speed 3m/min.