Abstract: An electromagnetic motor is described, the electromagnetic motor comprising: a magnet assembly configured to generate a two-dimensional alternating magnetic field having a pitch Pm1 in a first direction and a pitch Pm2 in a second direction; a coil assembly configured to co-operate with the magnet assembly to generate a first force in the first direction and a second force in the second direction, wherein the coil assembly comprises a first coil set comprising a plurality of first coils for generating the first force and a second coil set comprising a plurality of second coils for generating the second force, wherein a ratio R1 of a coil pitch Pc1 in the first coil set in the first direction over Pm1 is different from a ratio R2 of a coil pitch Pc2 in the second coil set in the second direction over Pm2.

Abstract: An electromagnetic motor is described, the electromagnetic motor comprising: a magnet assembly configured to generate a two-dimensional alternating magnetic field having a pitch Pm1 in a first direction and a pitch Pm2 in a second direction; a coil assembly configured to co-operate with the magnet assembly to generate a first force in the first direction and a second force in the second direction, wherein the coil assembly comprises a first coil set comprising a plurality of first coils for generating the first force and a second coil set comprising a plurality of second coils for generating the second force, wherein a ratio R1 of a coil pitch Pc1 in the first coil set in the first direction over Pm1 is different from a ratio R2 of a coil pitch Pc2 in the second coil set in the second direction over Pm2.

Abstract: An electromagnetic motor is described, the electromagnetic motor comprising: a magnet assembly configured to generate a two-dimensional alternating magnetic field having a pitch Pm1 in a first direction and a pitch Pm2 in a second direction; a coil assembly configured to co-operate with the magnet assembly to generate a first force in the first direction and a second force in the second direction, wherein the coil assembly comprises a first coil set comprising a plurality of first coils for generating the first force and a second coil set comprising a plurality of second coils for generating the second force, wherein a ratio R1 of a coil pitch Pc1 in the first coil set in the first direction over Pm1 is different from a ratio R2 of a coil pitch Pc2 in the second coil set in the second direction over Pm2.

Abstract: The present invention provides a tubular linear actuator, comprising: a tubular coil assembly comprising multiple tubular coils arranged next to each other in longitudinal direction of the tubular linear actuator and concentric with respect to a longitudinal axis of the tubular linear actuator, and a magnet assembly comprising a series of permanent magnets with alternating polarization direction extending in the longitudinal direction, wherein the magnet assembly is at least partially arranged in the coil assembly and movably with respect to the coil assembly, wherein the tubular coils comprise edge windings.

Abstract: The invention relates to a motor (LD) comprising: a stationary part (STP), comprising: a row of coil assemblies (UCA,LCA), the coil assemblies having multiple phases, a movable part (MP), comprising: a row of permanent magnets (UPM,LPM), wherein the row of coil assemblies has a first length and the row of permanent magnets has a second length, wherein the second length is smaller than the first length, wherein the coil assemblies are arranged to interact with permanent magnets aligned with the coil assemblies to generate a driving force, a comparator to compare a position measurement signal representative for an actual position of the movable part with a set-point signal representative for a desired position of the movable part to provide an error signal; a motion feedback controller configured to provide a control signal on the basis of the error signal; at least one current amplifier configured to provide an actuation signal to the coil assemblies on the basis of the control signal, wherein the motor compri

Abstract: The present invention provides a tubular linear actuator, comprising: a tubular coil assembly comprising multiple tubular coils arranged next to each other in longitudinal direction of the tubular linear actuator and concentric with respect to a longitudinal axis of the tubular linear actuator, and a magnet assembly comprising a series of permanent magnets with alternating polarization direction extending in the longitudinal direction, wherein the magnet assembly is at least partially arranged in the coil assembly and movably with respect to the coil assembly, wherein the tubular coils comprise edge windings.

Abstract: The invention relates to a motor (LD) comprising: a stationary part (STP), comprising: a row of coil assemblies (UCA,LCA), the coil assemblies having multiple phases, a movable part (MP), comprising: a row of permanent magnets (UPM,LPM), wherein the row of coil assemblies has a first length and the row of permanent magnets has a second length, wherein the second length is smaller than the first length, wherein the coil assemblies are arranged to interact with permanent magnets aligned with the coil assemblies to generate a driving force, a comparator to compare a position measurement signal representative for an actual position of the movable part with a set-point signal representative for a desired position of the movable part to provide an error signal; a motion feedback controller configured to provide a control signal on the basis of the error signal; at least one current amplifier configured to provide an actuation signal to the coil assemblies on the basis of the control signal, wherein the motor compri

Abstract: A reluctance actuator assembly comprising a reluctance actuator, a flux sensor to measure a magnetic flux in a gap of the reluctance actuator, and a flux amplifier to drive an actuator coil of the reluctance actuator based on a flux set point and the flux measured by the flux sensor. A method comprising providing to the flux amplifier a flux setpoint, the flux setpoint comprising a time constant component and a sinusoidally varying component at an excitation frequency, measuring a force generated by the reluctance actuator in response to the flux setpoint, and calibrating the reluctance actuator assembly from the measured force.

Abstract: An electromagnetic motor is described, the electromagnetic motor comprising: a magnet assembly configured to generate a two-dimensional alternating magnetic field having a pitch Pm1 in a first direction and a pitch Pm2 in a second direction; a coil assembly configured to co-operate with the magnet assembly to generate a first force in the first direction and a second force in the second direction, wherein the coil assembly comprises a first coil set comprising a plurality of first coils for generating the first force and a second coil set comprising a plurality of second coils for generating the second force, wherein a ratio R1 of a coil pitch Pc1 in the first coil set in the first direction over Pm1 is different from a ratio R2 of a coil pitch Pc2 in the second coil set in the second direction over Pm2.

Abstract: An actuator includes coil assemblies arranged in an array, wherein each coil assembly defines a core chamber having a core chamber height; and at least one magnetic member that extends partly along the core chamber height of the core chamber of a corresponding at least one coil assembly, wherein the at least one magnetic member is made of a magnetic material. A shape of the at least one magnetic member, a size of the at least one magnetic member, a position of the at least one magnetic member and/or the magnetic material of the at least one magnetic member may be selected so as to control one or more parameters of the actuator.

Abstract: An electromagnetic actuator includes a coil assembly including a coil; a magnet assembly including a first and a second magnet unit, each magnet unit including a magnetic yoke and a plurality of permanent magnets mounted to the magnetic yoke, the first and second magnet unit forming a magnetic circuit for receiving the coil assembly and, upon energizing the coil, generating a force in a first direction; and a holder for holding the magnet units, wherein a weight ratio of the magnet assembly over the coil assembly is smaller than the weight ratio of the magnet assembly over the coil assembly when the ratio of force over electrical power is maximized.

Abstract: An actuator includes coil assemblies arranged in an array, wherein each coil assembly defines a core chamber having a core chamber height; and at least one magnetic member that extends partly along the core chamber height of the core chamber of a corresponding at least one coil assembly, wherein the at least one magnetic member is made of a magnetic material. A shape of the at least one magnetic member, a size of the at least one magnetic member, a position of the at least one magnetic member and/or the magnetic material of the at least one magnetic member may be selected so as to control one or more parameters of the actuator.

Abstract: A lithographic apparatus includes an actuator for producing a force in a first direction between a first and a second part including a first magnet assembly and a second magnet assembly each attached opposite to each other to the first part of the apparatus, the first magnet assembly including a first main magnet system and a first outer subsidiary magnet system, and the second magnet assembly including a second main magnet system and a second outer subsidiary magnet system, the first and second main magnet system defining a space between them in a second direction perpendicular to the first direction. The actuator includes a coil attached to the second part. The distance between the first outer subsidiary magnet system and the second outer subsidiary magnet system in the second direction is substantially zero.

Abstract: A reluctance actuator assembly comprising a reluctance actuator, a flux sensor to measure a magnetic flux in a gap of the reluctance actuator, and a flux amplifier to drive an actuator coil of the reluctance actuator based on a flux set point and the flux measured by the flux sensor. A method comprising providing to the flux amplifier a flux setpoint, the flux setpoint comprising a time constant component and a sinusoidally varying component at an excitation frequency, measuring a force generated by the reluctance actuator in response to the flux setpoint, and calibrating the reluctance actuator assembly from the measured force.

Abstract: A lithographic apparatus includes an actuator for producing a force in a first direction between a first and a second part including a first magnet assembly and a second magnet assembly each attached opposite to each other to the first part of the apparatus, the first magnet assembly including a first main magnet system and a first outer subsidiary magnet system, and the second magnet assembly including a second main magnet system and a second outer subsidiary magnet system, the first and second main magnet system defining a space between them in a second direction perpendicular to the first direction. The actuator includes a coil attached to the second part. The distance between the first outer subsidiary magnet system and the second outer subsidiary magnet system in the second direction is substantially zero.