Abstract: A path module for a linear motor system includes a controller coupled to one or more amplifiers that are operative to control associated windings in the module. The controller receives control information via a communications link. The controller controls the amplifier based on the received control information so as to selectively energize the associated windings in the module. In one aspect, a plurality of such modules may be connected together to form a path along which one or more stages are moveable according to energization of the windings in the path.

Abstract: A magnet assembly includes a back iron and an array of magnets. The back iron is in the form of a plate having opposed surfaces. The magnets are arranged along one of the surfaces, with the other surface being dimensioned and configured according to the magnetic field distribution associated with the magnets. The back iron geometry provides for reduced mass, reduced leakage flux, and high flux densities to improve performance of a linear motor that employs such a magnet assembly.

Abstract: A rotary-linear actuator system, method of manufacturing and method of using a linear actuator are provided. An aspect of the invention includes a rotary-linear actuator having a spindle assembly and a housing assembly. The spindle assembly includes a plurality of annular magnets and a plurality of bar magnets affixed to a rotor. The plurality of annular magnets can be arranged with alternating polarity. The plurality of bar magnets can likewise be arranged with alternating polarity. The housing assembly includes a first set of coil(s) and a second set of coil(s). The spindle assembly can be movable and/or rotatable along a longitudinal axis extending through the spindle assembly. The first set of coil(s) can be arranged to, when energized, interact with at least one of the plurality of annular magnets to move the spindle assembly in a linear mode.

Abstract: A three phase linear motor system includes a forcer having three pole pairs, which are moveable relative to a platen. The pole pairs are arranged to oppose associated teeth of the platen. The platen teeth are spaced apart from each other in a travel direction according to a predefined tooth pitch. Each of the pole pairs includes a set of teeth that extend from magnetically coupled poles toward the platen. The set of teeth of one of the pole pairs is spaced from the sets of teeth for the other two poles by distances functionally related to about 120 degrees and 240 degrees, respectively, of the tooth pitch.

Abstract: A path for a linear motor system includes routing system between a trunk of the path and two or more branches. The routing system is operative to couple the trunk with a selected branch to enable a stage to travel between the trunk and the selected branch. The routing system includes armature windings that may be energized to effect movement of the stage in a desired direction between the trunk and the selected branch.

Abstract: A rotary-linear system is configured to operate an associated tool. The system includes a rotary-linear actuator having first and second portions that can move linearly and/or rotationally relative to each other, such as about a central axis extending through the actuator. An elongated drive rod extends axially through at least a portion of the actuator, which is operative to rotate about a longitudinal axis thereof generally independently of the actuator. While the rotation of the drive rod can be independent of movement of the actuator, such rotation can be controlled based on the position and/or movement of the actuator. An end of the drive rod near a distal end of the actuator is operative to actuate an associated tool, such as can be mounted at a distal end of the actuator.

Abstract: The present invention relates to a stability brake for absorbing parasitic vibrations of a stage moved to a working position in a motion system. The stability brake includes a motor coupled to a flexure plate through a translation system. The translation system translates horizontal motion of the motor into vertical motion of the flexure plate. The stability brake can be mounted to a stage in a motion system, such as a linear motion system. The stability brake is operative to absorb jitters and vibrations of the stage when the stage is moved to a working position in a motion system and held under servo at the working position.

Abstract: A system and method for a linear motor for driving a plurality of stages along a path are provided. The linear motor system includes a plurality of armature windings arranged to form a path, such as may be straight, curved, opened or closed. The stages include motor magnets that provide a magnet field. An encoder sensor is connected for movement with the stages so as to sense relative movement between the stages and the path. The encoder sensor further is operative to provide an encoder signal having an electrical characteristic indicative of relative movement between the stages and the path.

Abstract: The present invention relates to a stability brake for absorbing parasitic vibrations of a stage moved to a working position in a motion system. The stability brake includes a motor coupled to a flexure plate through a translation system. The translation system translates horizontal motion of the motor into vertical motion of the flexure plate. The stability brake can be mounted to a stage in a motion system, such as a linear motion system. The stability brake is operative to absorb jitters and vibrations of the stage when the stage is moved to a working position in a motion system and held under servo at the working position.

Abstract: A system and method are disclosed for improving resolution of an encoder or other position sensing device that provides one or more signals indicative of relative movement between two bodies. The signals are employed to determine an operating mode, which varies as a function of relative speed between the two bodies. In one operating mode, the system determines an indication of position by interpolating between position information of a table. Position also can be predicted in this operating mode, which can be used to update the position information. The table is populated with position information based on a sample of the signals from the position sensing device, such as to provide the position information for the table. In another operating mode, an indication of position is determined as a function of velocity and time.

Abstract: A three phase linear motor system includes a forcer having three pole pairs, which are moveable relative to a platen. The pole pairs are arranged to oppose associated teeth of the platen. The platen teeth are spaced apart from each other in a travel direction according to a predefined tooth pitch. Each of the pole pairs includes a set of teeth that extend from magnetically coupled poles toward the platen. The set of teeth of one of the pole pairs is spaced from the sets of teeth for the other two poles by distances functionally related to about 120 degrees and 240 degrees, respectively, of the tooth pitch.

Abstract: An encoder includes a plurality of magnetic zones of alternating polarity. At the opposed ends of the encoder magnet are magnetic end zones that provide substantially symmetric magnetic fields. The encoder sensors include first and second sensors that are spaced apart from each other a distance functionally related to the distance between the magnetic end zones. A plurality of first and second sensors are arranged so that the encoder magnet may move relative to the sensors. Each of the first and second sensors provides an associated output signal in response to magnetic influence of the encoder magnet moving past each respective encoder sensor. When each of the first and second encoder sensors senses one of the magnetic end zones of the encoder magnet, the associated output signals are substantially symmetric.

Abstract: A magnet configuration for a linear motor includes an array of a plurality of magnets having alternating polarity aligned to define a span. Additional magnets are positioned outside of the span near opposed ends of the span. Each of the additional magnets has a magnetic polarity opposite that of an adjacent one of the plurality of magnets at a corresponding opposed end of the span, such that the array of magnets provides a substantially sinusoidal magnetic field in the span.

Abstract: A force sensing system includes a pair of spaced apart magnets arranged to repel each other. A force sensor is operatively associated with one magnet of the pair of magnets and spaced apart from the other of the magnets. The one magnet preloads the force sensor based on interactions between magnetic fields of the magnets.

Abstract: A linear motor path forms a closed figure. Contactless power control and position feedback permit a linear motor stage to traverse the closed figure without interference from trailing wires. One embodiment of the closed figure includes a racetrack pattern with straight runs joined by curved ends. Axes of armature windings are skewed to lie across the path in the curved ends to maintain force on the linear motor stage. Other embodiments of the invention includes multilevel paths wherein one portion of the path crosses over another portion of the path. Disclosure is made of a linear motor stage supported below the path by magnetic attraction between permanent magnets on the stage and magnetic material in the path.

Abstract: An actuator, with two independent degrees of freedom, rotates a stage about an axis and moves the stage along the axis, the range of motion defining a cylinder or cylindrical section. The stage is mounted on a hollow cylindrical plunger fitting in an annular well. A bearing allows the plunger to move axially and rotationally, in the preferred embodiment the bearing is an air bearing. The plunger has an array of permanent magnets on its external cylindrical face opposite coils in the well. Equal numbers of oppositely-polarized permanent magnets are arranged in a regular cylindrical pattern at 50% packing density forming rings and columns of like-polarity magnets, the rings of one polarity alternating with rings of opposite polarity and the columns of one polarity alternating with columns of opposite polarity. A set of Z-axis coils (for axial movement) curve around the plunger and are shaped to allow a current in them to produce an axial force with respect to the rings of magnets.

Abstract: An actuator, with two independent degrees of freedom, rotates a stage about an axis and moves the stage along the axis, the range of motion defining a cylinder or cylindrical section. The stage is mounted on a hollow cylindrical plunger fitting in an annular well. A bearing allows the plunger to move axially and rotationally, in the preferred embodiment the bearing is an air bearing. The plunger has an array of permanent magnets on its external cylindrical face opposite coils in the well. Equal numbers of oppositely-polarized permanent magnets are arranged in a regular cylindrical pattern at 50% packing density forming rings and columns of like-polarity magnets, the rings of one polarity alternating with rings of opposite polarity and the columns of one polarity alternating with columns of opposite polarity. A set of Z-axis coils (for axial movement) curve around the plunger and are shaped to allow a current in them to produce an axial force with respect to the rings of magnets. A set of .phi.

Abstract: An X-Y positioning machine has a forcer, with armature coils, that moves around on a platen, supported by an air bearing. Magnets embedded in the motor platen generate a fixed magnetic field with which the armature coils interact. Perpendicular elongated coils interact with the fields of magnets in columns and rows. When a traditional rectangular pattern of the magnets is provided, a packing density and average peak magnetic flux intercepted by the coils are limited to 50%. The present invention provides magnet configurations that provide greater than 50% maximum peak flux density and up to 100% packing density. Several magnet arrangements are provided: a first in which round magnets are used instead of square, and a second in which diamond-shaped magnets are used. The latter can be used at 100% packing density arrangement. In addition to high peak flux density for a narrow coil, these embodiments exhibit low cogging forces. A method of making the magnet is also provided.

Abstract: An X-Y traversing machine employs optical pickups on a stage that moves around a base on an air bearing. A pattern of dots on the surface of the base forms a scale. Respective X- and Y-direction optical pickups are used to detect incremental movement in X- and Y-directions independently. Each pickup averages the reflected light from an elongated rectilinear region whose long axis is aligned perpendicular to the direction of movement the pickup detects. The dots are formed on an encoder scale element. According to an embodiment of the invention, forces are developed without using serrations in the stage and magnets so that a substantial spacing between the coils and field generator (permanent magnets in the preferred embodiment) can be tolerated. This allows the encoder scale to be placed on or protected by a sheet between the platen and the stage. [For example, the pattern may be printed on a flexible transparent Mylar sheet that can be readily replaced if damaged.

Abstract: An X-Y positioning machine has a forcer, with armature coils, that moves around on a platen, supported by an air bearing. Magnets embedded in the motor platen generate a fixed magnetic field with which the armature coils interact. Perpendicular elongated coils interact with the fields of magnets in columns and rows. When a traditional rectangular pattern of the magnets is provided, a packing density and average peak magnetic flux intercepted by the coils are limited to 50%. The present invention provides magnet configurations that provide greater than 50% maximum peak flux density and up to 100% packing density. Several magnet arrangements are provided: a first in which round magnets are used instead of square, and a second in which diamond shaped magnets are used. The latter can be used at 100% packing density arrangement. In addition to high peak flux density for a narrow coil, these embodiments exhibit low cogging forces. A method of making the magnet is also provided.