Lightweight linear motor

Claim 2

A linear positioning motor comprising: a support structure including a central linear guide rod extending over the full effective length of the support structure and further including channel means spaced from and parallel to the rod and extending over at least a portion of the rod length; a voice coil assembly: means mounting the voice coil assembly for linear movements along the rod; magnet means spaced from and parallel to the rod extending over a portion of the rod length; means connected with the assembly and extending into the channel means to prevent rotational movements of the assembly; and means for subjecting the assembly to current for moving the assembly along the rod.

Claim 3

A motor according to claim 1 wherein the magnet means includes a surface parallel to the rod, and including means supporting a portion of the assembly on the surface during all movements of the assembly along the rod.

Claim 4

A motor according to claim 1 wherein the assembly mounting means comprises sleeve bearings.

Claim 5

A low-cost, lightweight linear motor for accurately positioning a recording head or the like along a straight line comprising: a support structure; magnet means secured to the structure and defining an annular elongate space; an annular electric coil assembly insertable into the annular space; sliding bearing means affixed to said assembly for supporting a portion of the assembly on said magnet means and permitting linear assembly movements along the axis of the annular space and means for mounting the recording head or the like to an end of the assembly.

Claim 6

A low-cost, lightweight linear motor for accurately positioning a recording head or the like along a straight line comprising: a support structure; magnet means secured to the structure and defining an annular elongate space; an annular electric coil assembly insertable into the annular space; sliding bearing means affixed to said assembly for supporting a portion of the assembly on said magnet means and permitting linear assembly movements along the axis of the annular space and means for mounting the recording head or the like to an end of the assembly.

Claim 7

A motor according to claim 4 including a guide rod secured to the support structure and disposed concentrically with the annular space, wherein the assembly includes carriage means disposed at one end of the assembly, and wehrein the sliding bearing means includes a first sleeve bearing disposed adjacent another end of the assembly, and a second sleeve bearing secured to the carriage means and engaging the rod for slidable movement therealong.

Claim 8

A motor according to claim 5 including bar means projecting from the structure and oriented parallel to the guide rod, and including sliding pads mounted to the carriage means engaging the bar means and preventing rotational movements of the carriage means and the assembly about the concave surface and the guide rod.

Claim 9

A motor according to claim 4 including a guide rod secured to the support structure concentrically with the annular space and having a length at least about twice the length of the annular space, wherein the magnet means is defined by an outer annular magnet and an inner annular magnet pole piece spaced from the outer magnet to define the annular space, the pole piece being further spaced from the guide rod, means concentrically supporting the magnet and the pole piece, the supporting means including disk means facing in the direction of the guide rod, and wherein the coil assembly includes a carriage slidable along the guide rod between a free end thereof and the disk means for supporting one end of the coil assembly.

Claim 10

A motor according to claim 7 including at least one annular stop ring disposed about the guide rod and resting against the disk means for limiting the movement of the coil assembly, the stop ring being constructed of a resilient material to limit the deceleration forces when the moving carriage means engages the ring.

Claim 11

A lightweight linear motor for precision positioning an object along a straight line comprising a support structure, a guide rod having ends secured to the support structure and an intermediate portion spaced from the structure, an annular pole piece having a lesser length than the guide rod and a first end secured to the support structure adjacent a point where an end of the guide rod is secured to the structure, the pole piece extending in the direction of the rod and having a free second end, an annular magnet having a first end securEd to the support structure adjacent the point, the magnet terminating at a second end approximately aligned with the second end of the pole piece, the pole piece and the magnet being spaced from each other to define an annular space between them defined by at least one cylindrical surface which is concentric with the rod, an annular voice coil assembly having a lesser length than the rod, and being dimensioned to be insertable into the annular space, one end of the assembly including a first sliding sleeve engaging the cylindrical surface for guidance during linear slidable movements of the assembly, another end of the assembly being defined by a carriage having a second sleeve bearing in sliding engagement with the rod for linear slidable movement therealong and an arm extending generally radially away from the bearing towards the support structure, at least one elongate protrusion parallel to the rod defined by the support structure, means defined by the arm for preventing rotational movements of the assembly, means for securing the object to the carriage, a conductor secured to the assembly and dimensioned to be disposed within the annular space at all operative positions of the assembly in the annular space, and means for supplying the conductor with electric current so that an electromotive force generated between the conductor and the magnets linearly moves the assembly along the rod and the cylindrical surface.

Claim 12

A lightweight linear motor for precision positioning an object along a straight line comprising a support structure, a guide rod having ends secured to the support structure and an intermediate portion spaced from the structure, an annular pole piece having a lesser length than the guide rod and a first end secured to the support structure adjacent a point where an end of the guide rod is secured to the structure, the pole piece extending in the direction of the rod and having a free second end, an annular magnet having a first end securEd to the support structure adjacent the point, the magnet terminating at a second end approximately aligned with the second end of the pole piece, the pole piece and the magnet being spaced from each other to define an annular space between them defined by at least one cylindrical surface which is concentric with the rod, an annular voice coil assembly having a lesser length than the rod, and being dimensioned to be insertable into the annular space, one end of the assembly including a first sliding sleeve engaging the cylindrical surface for guidance during linear slidable movements of the assembly, another end of the assembly being defined by a carriage having a second sleeve bearing in sliding engagement with the rod for linear slidable movement therealong and an arm extending generally radially away from the bearing towards the support structure, at least one elongate protrusion parallel to the rod defined by the support structure, means defined by the arm for preventing rotational movements of the assembly, means for securing the object to the carriage, a conductor secured to the assembly and dimensioned to be disposed within the annular space at all operative positions of the assembly in the annular space, and means for supplying the conductor with electric current so that an electromotive force generated between the conductor and the magnets linearly moves the assembly along the rod and the cylindrical surface.

Claim 13

A motor according to claim 9 wherein the carriage comprises a lightweight plastic molding.

Claim 14

A motor according to claim 10 wherein th molding is defined by a disk portion disposed about the rod, and wherein the arm extends radially outwardly from the disk portion, the disk portion defining a hub mounting the second bearing to the carriage and a plurality of apertures permitting air communication from one side of the disk portion to the other side to prevent the formation of a vacuum or the build-up of pressure within spaces enclosed by the magnets during operation of the motor.

Claim 15

A motor according to claim 11 wherein the assembly includes a tubular plastic shell insertable into the annular space, and wherein the conductor is wound about the exterior of the plastic shell.

Claim 16

A motor according to claim 12 including means supporting the free second end of the pole piece on the rod, and including at least one resilient O-ring disposed on the side of the last mentioned means facing towards the carriage for providing a resilient stop limiting slidable movements of the carriage towards the pole piece and reducing the deceleration forces to which the carriage is exposed. like

Claim 17

A motor according to claim 9 wherein the magnet comprises a permanent ceramic magnet, wherein the pole piece defines the cylindrical surface in the form of a concave surface, and wherein the first bearing slidably engages the concave surface of the pole piece.

Claim 18

A motor according to claim 9 wherein the protrusion comprises a pair of parallel, spaced apart protrusions constructed integrally with the support structure and defining parallel opposing faces extending parallel to the rod, and wherein the arm includes an end portion and friction pads positioned to engage and slide along the parallel protrusion faces to thereby prevent rotational movements of the assembly about the rod.

Claim 19

A motor according to claim 9 wherein the support structure includes an end plate demountably fastened to a base plate and extending substantially perpendicularly away therefrom, the end plate including first and second annular shoulders for securing the magnets to the end plate, and a bore concentric with the shoulders for engaging the guide rod, and including means demountably fastening the magnets and the guide bar to the support structure.

Claim 20

A linear positioning motor, comprising: a support structure including a central linear guide rod; magnet means spaced from and concentric with said guide rod and extending over at least a portion of the rod length, said magnet means defining an annular channel spaced outwardly from said rod; a voice coil assembly adapted for movement within said channel axially of said rod; slidable bearing means associated with said assembly and mounting at least a portion of said assembly on said magnet means for reciprocal linear movement within said channel; and means for subjecting said assembly to electrical current for movement within said channel.

Claim 21

A linear positioning motor, comprising: a support structure including a central linear guide rod; magnet means spaced from and concentric with said guide rod and extending over at least a portion of the rod length, said magnet means defining an annular channel spaced outwardly from said rod; a voice coil assembly adapted for movement within said channel axially of said rod; slidable bearing means associated with said assembly and mounting at least a portion of said assembly on said magnet means for reciprocal linear movement within said channel; and means for subjecting said assembly to electrical current for movement within said channel.

Claim 22

A motor according to claim 17, wherein said slidable bearing means comprises at least one sleeve-bearing affixed to at least a portion of the interior surface of said voice coil assembly and adapted for slidable movement along a convex surface of said magnet means defining a wall of said annular channel.

Claim 23

A linear positioning motor comprising: a support structure including a central linear guide rod; a voice coil assembly; means slidably mounting a portion of the voice coil assembly on the rod for linear movement therealong; magnet means parallel to and spaced outwardly from the rod and extending over a portion of the rod length; means slidably mounting another portion of the voice coil assembly on a surface of the magnet means for linear movement therealong; and means for subjecting the assembly to current for moving the assembly along the rod.

Claim 24

A linear positioning motor comprising: a support structure including a central linear guide rod; a voice coil assembly; means slidably mounting a portion of the voice coil assembly on the rod for linear movement therealong; magnet means parallel to and spaced outwardly from the rod and extending over a portion of the rod length; means slidably mounting another portion of the voice coil assembly on a surface of the magnet means for linear movement therealong; and means for subjecting the assembly to current for moving the assembly along the rod.