Displacement device

A displacement device with a first part and a second part which are displaceable relative to one another in at least one direction (x), said first part comprising a carrier which extends substantially parallel to the displacement direction and on which a system of magnets is fastened in accordance with a pattern whereby magnets of a first kind (N) with a magnetization direction perpendicular to the carrier and directed towards the second part and magnets of a second kind (Z) with a magnetization direction perpendicular to the carrier and directed away from the second part are arranged so as to alternate with one another, which system of magnets has a magnetic flux density which repeats itself periodically in accordance with B(x)=B(x+2τ), in which τ is the magnetic pole pitch, while the second part is provided with an electric coil system with at least one coil block unit comprising k coil blocks, with k≧2, which coil blocks have current conductors which are situated in a magnetic field of the system of magnets, all current conductors belonging to one coil block unit being oriented in the same direction and being fed by an n-phase system, with n≧2, while furthermore the magnets of the magnetic system are arranged such that, viewed in a direction perpendicular to the current conductors, the flux of the magnetic system varies substantially sinusoidally in accordance with

• 10 Φ = sin ⁢ π ⁡ ( x + x 0 ) 2 ⁢ τ .
• characterized in that it is true for all coil blocks belonging to one coil block unit that the distance between mass centers of consecutive coil blocks, viewed in a direction perpendicular to the conductors, is substantially equal to
• 11 τ k + p × τ , with ⁢ ⁢ p = 2 , 3 , … ⁢ .