Patent ID: 6713899
Filing Date: 2004-03-30
Classification: H02K

Abstract:
A linear synchronous motor comprising:a) at least one primary part (1) and at least one secondary part (6); b) the secondary part (6) has a sequence of poles (10) formed by permanent magnets; c) the length of the secondary part (6) is greater than the length of the primary part (1) in the movement direction (5), d) the primary part (1) has primary part slots (9) which are suitable for holding monophase or polyphase windings, e) the primary part (1) has means which lead to a change in the magnetic force in the movement direction (5) of the linear motor in the region of the end pieces (2) of the primary part (1), and f) the end faces (14) of the end pieces (2) extend perpendicular to the movement direction (5) of the linear motor, wherein the air gap between the end pieces (2) and the part (6) changes gradually within a single pole pitch so as to realize a continuous increase or decrease in the magnetic force in the movement direction (5) of the linear motor in the region of the end pieces (2) of the primary part (1), wherein the geometry of the parts, facing the air gap, of the end pieces (2) is selected in accordance with the following relationship: y&it;â€ƒ&it;(x)=Î´0&af;[11-xx0&CenterDot;[1-(11+y0Î´0)]-1]wherein &dgr;0 is the magnetically active air gap between the secondary part and the primary part, including the height of the permanent magnets, x0 is the extent of the part of the end piece in the direction of movement of the linear motor having a non-constant air gap, y0 is a height of the part of the end piece having a non-constant air gap at x0 and, y(x) is the coordinate of the part of the end piece having a non-constant air gap at the point x.