Nikon Corporation

Mainspring Energy, Inc.

Etagen, Inc.

Scott Coakley

Michael B Binnard

John Lawler

John Powers

Kevin Walters

David B DeGraaff

Pai-Hsueh Yang

Matt Svrcek

Bausan Yuan

Christopher David Gadda

Andrew H Hancock

Shannon Miller

Jodie Prudhomme

Kazuhiro Hirano

Matthew Svrcek

Cameron Wylie

Alan Crapo

Samuel Sherman

Sam Sherman

Shiang-Lung Koo

Douglas C Watson

Alexander H Cooper

Alton Hugh Phillips

Radka Tezaur

Kazuo Masaki

Xiao-Feng Yang

David Degraaff

A linear electromagnetic machine includes a stator, a translator, and a bearing system. The bearing system maintains alignment against lateral displacement of the translator relative to the stator, as the translator reciprocates axially. More particularly, the bearing system maintains a motor air gap between the stator and a magnetic section of the translator. The stator includes a plurality of stator teeth and windings, which form a plurality of phases. The stator teeth and windings are arranged using a hoop stack with spines to form a stator bore and define the motor air gap. The bearing system can include bearing housings that are configured to form a bearing interface with a surface of the translator. The bearing interface can include a contact bearing or a non-contact bearing, such as a gas bearing. Current is controlled in the phases to convert between electrical energy and kinetic energy of the translator.

Linear electromagnetic machine with a stator having stator teeth arranged to provide an anti-clocking force

An integrated linear generator system includes, for example, a generator assembly, a control system, a frame system, an exhaust system, an intake system, a cooling system, a bearing system, one or more auxiliary systems, or a combination thereof. The generator system is configured to generate power, as controlled by the control system. The generator assembly may include an opposed- and free-piston linear generator, configured to operate on a two-stroke cycle. The intake and exhaust systems are configured to provide reactants to and remove products from the generator assembly, respectively. The cooling system is configured to effect heat transfer, material temperature, or both, of components of the integrated linear generator system. The bearing system is configured to constrain the off-axis motion of translators of the generator assembly without applying significant friction forces. The frame system is configured to manage rigidity, flexibility, and alignment of components of the integrated linear generator system.

Integrated linear generator system

Linear electromagnetic machine system

Linear electromagnetic machine system with bearing housings having pressurized gas

An element is provided to maintain a clearance gap between a piston and a cylinder wall. In some embodiments, an element is included that is capable of spatial change. In some embodiments, the element is a component such as a clearance ring, a surface bearing, or a segment of a clearance ring or surface bearing. A clearance gap may be maintained by inward and outward motion of the component with respect to a piston assembly and a cylinder wall, where the motion is determined by a balance of forces acting on the component. In some embodiments, an inward force generated by an external gas pressure source is balanced by an outward preload force generated by, for example, a pneumatic piston. In some embodiments, a clearance gap is maintained based on in part on the ratio of inner to outer surface areas of a clearance ring.

Mechanism for maintaining a clearance gap

An exemplary stage assembly has movable stage mass and counter-mass. A stage motor is coupled to the stage mass and counter-mass such that stage-mass motion imparted by the stage motor causes a reactive motion of the counter-mass counter to the motion of the stage mass. At least one trim-motor is coupled to the counter-mass. A control system commands the trim-motor to regulate movement of the counter-mass in reaction to stage-mass motion. A PI feedback controller receives the following-error of the counter-mass and generates corresponding center-of-gravity (CG) force commands and trim-motor force commands to the trim-motor(s) to produce corrective counter-mass motion. A trim-motor force limiter receives trim-motor force commands and produces corresponding limited trim-motor force commands that are fed back as actual CG force commands to the feedback controller to modify integral terms of the feedback controller according to the limited trim-motor force commands.

Methods for limiting counter-mass trim-motor force and stage assemblies incorporating same

A method for determining a commutation offset for a mover (A) of a mover assembly (C) that moves and positions a stage (A) relative to a stage base (B) includes controlling the mover assembly (C) in a closed loop fashion to maintain the position of the stage (A) along a first axis and along a second axis with the stage (A) levitated above the stage base (B). The method also includes the steps of (i) directing current to a coil array () of the mover assembly (C) so that the mover assembly (C) imparts a disturbance on the stage (A); and (ii) evaluating one or more forces generated by the mover assembly (C) as a result of the disturbance on the stage (A) created by the mover (A). Further, a method for generating a compensation map () includes sequentially directing a plurality of excitation signals to the control of the mover assembly (C) and determining the control commands that result from the plurality of excitation signals.

Method for determining a commutation offset and for determining a compensation map for a stage

Method for determing a commutation offset and for determining a compensation map for a stage

Embodiments of the invention compensate for one or more effects of a stage motor in a precision stage device. A feedforward module receives an input signal corresponding to the effect of the motor and generates a feedforward control signal that can be used to modify a motor control signal to compensate for the effect of the motor. In some embodiments, a control system is provided to compensate for a back-electromotive force generated by a motor, while in other embodiments, a control system may compensate for an inductive effect of a motor. Embodiments of the invention may be useful in precision stage devices, for example, lithography devices such as steppers and scanners.

Control systems and methods for compensating for effects of a stage motor

Embodiments of the invention provide improved thermal conductivity within, among other things, electromagnetic coils, coil assemblies, electric motors, and lithography devices. In one embodiment, a thermally conductive coil includes at least two adjacent coil layers. The coil layers include windings of wires formed from a conductor and an insulator that electrically insulates the windings within each coil layer. In some cases the insulator of the wires is at least partially absent along an outer surface of one or both coil layers to increase the thermal conductivity between the coil layers. In some embodiments, an insulation layer is provided between the coil layers to electrically insulate the coil layers. In some cases the insulation layer has a thermal conductivity greater than the thermal conductivity of the wire insulator.

Thermally conductive coil and methods and systems

Methods and apparatus for adjusting the amount of current provided to a magnetic actuator to compensate for a temperature change associated with the magnetic actuator are disclosed. According to one aspect of the present invention, an apparatus includes an actuator, which has at least one magnet and an associated force constant. The apparatus also includes a temperature sensing arrangement and a control arrangement, the temperature sensing arrangement being arranged to determine or measure a temperature of the magnet. The control arrangement adjusts the current provided to the actuator based on the temperature of the magnet. The current is adjusted to maintain a correct or desired force in light of temperature-induced variations to a force constant.

Compensating temperature effects in magnetic actuators

An exemplary stage apparatus has a motor, stage, and position-measuring device. The motor has a planar stator and moving-coil mover (planar motor). The stator is a checkerboard magnet array extending in an x-y plane and producing a magnetic field having a field period of 2&#x3c0; in a u-v coordinate system rotated 45&#xb0; from the x-y coordinate system of the plane. The stage, coupled to the mover, moves with corresponding motions of the mover relative to the stator. The position-measurement device includes a first group of four magnetic-field sensors that are movable with the stage. The sensors are situated at integer multiples of &#x3c0;/2 from each other in u- and v-directions of the u-v coordinate system. The sensors produce respective data regarding a respective component of the magnetic field at, and hence the position of, the respective sensor within the period of the magnetic field.

Apparatus and methods for determining an initially unknown commutation position of a member moved by a planar motor

A mover () moving a stage () along a first axis, along a second axis and along a third axis includes a magnetic component (), a conductor component (), and a control system (). The magnetic component () includes a plurality of magnets (D) that are surrounded by a magnetic field. The conductor component () is positioned near the magnetic component () in the magnetic field. Further, the conductor component () interacts with the magnetic component () when current is directed to the conductor component () to generate a controllable force along the first axis, a controllable force along the second axis, and a controllable force along the third axis. The conductor component () can include a split coil design, having a first conductor array (A) and a second conductor array (B) that is positioned substantially adjacent to the first conductor array (A). The conductor component () and the magnetic component () can be displaced relative to each other along the third axis. The control system () independently directs current to each of the conductor arrays (A,B) to generate a controllable force along the first axis, along the second axis, and along the third axis. With this design, the same mover can be used to move the stage along three degrees of freedom ('DOF').

Three axis linear actuator

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Belmont, CA, United States of America

Scott Coakley