Abstract: A linear electrical machine (LEM) comprising a stator mounted in a housing, the housing and stator defining a working cylinder, a central core within the working cylinder and defining a cylindrical stator bore cavity therebetween, a hollow translator axially movable within the working cylinder, extending into the stator bore cavity and forming an exterior magnetic circuit airgap between the translator and the stator, at least one fluid bearing between the central core and the translator providing a bearing gap, wherein the central core is axially fixed in relation to the stator, wherein the at least one fluid bearing provides coaxial location of the translator and central core.

Abstract: An actuator comprising a linear electrical machine (LEM) having a stator with a stator bore and a translator axially movable within the stator bore and defining a magnetic circuit airgap therebetween, at least one fluid bearing journal formed on the translator, at least one fluid bearing providing a bearing gap adjacent the translator to allow the translator to move axially within the stator bore, a preload chamber for applying a preload force to the translator, wherein the preload chamber is defined by a side wall, a first end wall and a second end wall at least part of which is movable with the translator, and wherein the bearing gap and the magnetic circuit airgap are coaxial.

Abstract: A linear electrical machine (LEM) comprising: at least onestator mounted in a housing, the housing and stator defining a working cylinder; a two-section central core within the working cylinder, wherein the two sections of the core are co-axial, separate and cantilever mounted within the working cylinder; a cylindrical stator bore cavity between the working cylinder and the two central core sections; and one or more hollow translators, each translator being axially movable within the stator bore cavity, such that each section of the central core is traversed by part of the one or more translators, thereby forming an exterior magnetic circuit airgap between the respective translator and stator.

Abstract: An actuator comprising a linear electrical machine (LEM) having a stator with a stator bore and a translator axially movable within the stator bore and defining a magnetic circuit airgap therebetween, at least one fluid bearing journal formed on the translator, at least one fluid bearing providing a bearing gap adjacent the translator to allow the translator to move axially within the stator bore, a preload chamber for applying a preload force to the translator, wherein the preload chamber is defined by a side wall, a first end wall and a second end wall at least part of which is movable with the translator, and wherein the bearing gap and the magnetic circuit airgap are coaxial.

Abstract: A linear electrical machine (LEM) comprising a stator mounted in a housing, the housing and stator defining a working cylinder, a central core within the working cylinder and defining a cylindrical stator bore cavity therebetween, a hollow translator axially movable within the working cylinder, extending into the stator bore cavity and forming an exterior magnetic circuit airgap between the translator and the stator, at least one fluid bearing between the central core and the translator providing a bearing gap, wherein the central core is axially fixed in relation to the stator, wherein the at least one fluid bearing provides coaxial location of the translator and central core.