This paper describes a linear dc motor (LDM) with an exciting circuit that uses Reed switches to simplify the exciting circuit (R-LDM). The Reed switches are connected to both sides of the exciting coils, thus simplifying the structure of the exciting circuit The switches are changed by switching magnets arranged on the mover. The characteristics of the manufactured LDM are as follows:
1. To use the magnetic fluxes of the magnets effectively, an LDM with an odd number of poles is more suitable than one with an even number of poles.
2. The measured thrust constant is 2.13 N.
3. The value of the pole pitch which minimizes pulsating coefficient of the static thrust is 32 mm for the coil pitch of 40 mm and then pulsating coefficient of the static thrust is 4.6% at the maximum. It is clear that the pole pitch of the manufactured R-LDM may be given fittingly.