Linear motor

Claim 2

A linear motor comprising a stator having a generally tubular shape, an even number of ferromagnetic elements having the shape of a helix disposed coaxially within said stator, and a movable member disposed within said stator and including means for producing a rotating field coaxial with said stator so as to produce a linear movement of said movable member along the axis of said stator as a result of the interaction between said rotating field and said ferromagnetic elements, said stator being longitudinally interrupted along a line parallel to its axis and said movable member being mechanically connected to an object to be moved, placed outside of the stator by a linkage traversing said longitudinal interruption.

Claim 3

A linear motor according to claim 1 wherein said stator is made from a material other than ferromagnetic material.

Claim 4

A linear motor according to claim 2 wherein said ferromagnetic elements are directly connected mechanically to said stator.

Claim 5

A linear motor according to claim 1 wherein said stator is entirely constituted of a ferromagnetic material, and wherein said ferromagnetic elements in helical form are provided as projections disposed on the internal surface of the generally tube-shaped stator.

Claim 6

A linear motor according to claim 1 wherein two identical movable members are disposed iN said stator and connected to said object, said members being spaced by one-half a pitch of said helical shaped ferromagnetic elements.

Claim 7

A linear motor according to claim 5, characterized in that said movable members include bipolar inductive elements disposed in such a manner that their respective fields are in the same direction.

Claim 8

A linear motor according to claim 1, characterized in that said movable member includes a polyphase winding supplied with an alternating electric current.

Claim 9

A linear motor according to claim 7, characterized in that said polyphase windings are inclined at the same pitch as said ferromagnetic elements.

Claim 10

A linear motor according to claim 1, characterized in that said movable member is constituted by a permanent magnet, and in that said permanent magnet is driven in rotation about the axis of said stator by an auxiliary motor.

Claim 11

A linear motor according to claim 9, characterized in that the poles of said permanent magnet are inclined at the pitch of said ferromagnetic elements.

Claim 12

A linear motor according to claim 5, characterized in that a ferromagnetic piece is disposed parallel to the axis of the stator at the level of the longitudinal opening therein and is connected by means of a non-magnetic support to a non-magnetic connecting element for connecting the two movable members.

Claim 13

A linear motor according to claim 1, characterized in that the width of the longitudinal interruption of the stator is smaller than the width of said movable member.

Claim 14

A linear motor according to claim 1, characterized in that said ferromagnetic elements are laminated.

Claim 15

A linear motor according to claim 1, characterized in that said stator comprises n movable members distributed in such a manner that the magnetic field of each movable member is dephased by 2 pi /n with respect to the magnetic field of the preceding movable member.

Claim 16

A linear motor according to claim 1, characterized in that said movable member is constituted by a winding connected to a source of direct current, and in that said winding is driven in rotation about the axis of said stator by an auxiliary motor.

Claim 17

A linear motor comprising a stator having a generally cylindrical hollow and being interrupted longitudinally along a line parallel to its axis, said stator including an even number of active parts made from ferromagnetic material having the form of helices disposed coaxially within said cylindrical hollow, and inactive parts made from a non-ferromagnetic material forming said cylindrical hollow and providing the support of said active parts therein, and means for guiding and supporting a structural member disposed outside of the stator and mechanically connected to at least one assembly of two inductors disposed within said cylindrical hollow, said inductors comprising polyphase windings, placed concentrically within said cylindrical hollow, the two inductors being connected by a non-magnetic mechanical connection on which there is mounted a support on which is secured a ferromagnetic piece disposed parallel to the axis of the cylindrical hollow and placed at the level of the longitudinal interruption in said stator which serves to periodically open said helices.

Claim 18

A linear motor comprising a stator having a generally cylindrical hollow and being interrupted longitudinally along a line parallel to its axis, said stator including an even number of active parts made from ferromagnetic material having the form of helices disposed coaxially within said cylindrical hollow, and inactive parts made from a non-ferromagnetic material forming said cylindrical hollow and providing the support of said active parts therein, and means for guiding and supporting a structural member disposed outside of the stator and mechanically connected to at least one assembly of two inductors disposed within said cylindrical hollow, said inductors comprising polyphase windings, placed concentrically within said cylindrical hollow, the two inductors being connected by a non-magnetic mechanical connection on which there is mounted a support on which is secured a ferromagnetic piece disposed parallel to the axis of the cylindrical hollow and placed at the level of the longitudinal interruption in said stator which serves to periodically open said helices.