Switch and associated methods

Abstract

The present invention is related to a switching device having a contactor and an actuator. The contactor has at least a first contactor member and a second contactor member. The actuator is configured to actuate the contactor. At least one of the contactor members has a varying or variable thickness along its length such that the at least one of the contactor members has a relatively thick portion and a relatively thin portion.

Claims

1. A switching device comprising: a contactor comprising at least a first contactor member and a second contactor member; and an actuator configured to actuate the contactor, wherein at least one of the first and second contactor members comprises a bus-bar and a moving blade, wherein the bus-bar is electron beam welded to the moving blade, and wherein the switching device is a mains electricity smart meter remotely-operated switching device.

2. The switching device of claim 1, wherein the-bus-bar is configured to dissipate heat at an increased rate by comprising a surface area of at least one face that is substantially greater than the footprint and planar projection of said face, and the at least one contactor member comprises at least one of: a plurality of protrusions in the at least one face; and a plurality of recesses in the at least one face.

3. A method of-connecting the moving blade of the contactor member of the switching device of claim 1, the method comprising-electron beam welding the moving blade to the bus-bar.

4. The switching device of claim 1, wherein the contactor member comprising the bus-bar and the moving blade is a single unitary piece, wherein the bus-bar and the moving blade are integral.

5. The switching device of claim 1, comprising an aligned force transmission system configured to balance forces transmitted between the actuator and the contactor.

6. The switching device of claim 5, wherein the actuator and the contactor are arranged such that force is transmitted between components of the actuator and the contactor substantially in a plane.

7. The switching device of claim 1, wherein the bus-bar and moving blade are substantially continuous.

8. The method of claim 3, comprising transmitting forces between the actuator and contactor of the switching device through an aligned force transmission system.

9. The method of claim 8, comprising arranging the actuator and the contactor such that force is transmitted between components of the actuator and the contactor substantially in a plane.

10. The method of claim 3, comprising dissipating heat from the bus-bar at an increased rate by providing a surface area of at least one side or face of the bus-bar that is substantially greater than the footprint and the planar projection of said side or face.

11. A switching device comprising: a contactor comprising at least a first contactor member and a second contactor member; and an actuator configured to actuate the contactor, wherein at least one of the contactor members comprises a first, thick portion, which is thick relative to a second, thin portion, wherein the thick portion comprises a bus-bar and the thin portion comprises a moving blade, and wherein the bus-bar and the moving blade are homogenous, both comprising a same homogeneous property of at least one of: an electrical property; and a thermal property.

12. The switching device of claim 11, wherein the switching device is a mains electricity smart meter remote disconnect switching device.

13. The switching device of claim 11, wherein the bus-bar is configured to dissipate heat at an increased rate.

14. The switching device of claim 13, wherein the bus-bar comprises a surface area of at least one side or face that is substantially greater than the footprint and planar projection of said side or face.

15. The switching device of claim 11, comprising an aligned force transmission system configured to balance forces transmitted between the actuator and the contactor.

16. The switching device of claim 15, wherein the actuator and the contactor are arranged such that force is transmitted between components of the actuator and the contactor substantially in a plane.

17. The switching device of claim 11, wherein the bus-bar and the moving blade comprise a similar type of material and a similar electrical property and a similar thermal property.

18. The switching device of claim 11, wherein the at least one of the contactor members does not comprise a boundary between the bus-bar and the moving blade.

19. The switching device of claim 11, wherein the at least one of the contactor members is a continuous integral unitary contactor member of variable thickness, the moving blade and the bus-bar comprising at least one continuous surface extending from the bus-bar to the moving blade.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and other aspects of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

(2) FIG. 1 shows a switching device in accordance with a first embodiment of the invention in an ON configuration;

(3) FIG. 2 shows a cross sectional view of the switching device of FIG. 1;

(4) FIG. 3 shows a detail view of a portion of an actuator of the device of FIG. 1;

(5) FIG. 4 shows a side view of a portion of a contactor of the device of FIG. 1;

(6) FIG. 5 shows a first contactor member of the device of FIG. 1; and

(7) FIG. 6 shows a second contactor member of the device of FIG. 1.

DETAILED DESCRIPTION OF THE DRAWINGS

(8) Reference is first made to FIG. 1 of the drawings, which illustrates a switching device 10, in accordance with an embodiment of the present invention.

(9) The switching device 10 comprises an actuator 12 and a contactor 14. The actuator 12 is configured to actuate the contactor 14. The contactor 14 comprises a first contactor member 16 and a second contactor member 18.

(10) The first contactor member 16 comprise a variable thickness, with a relatively thin portion 20 with a moving blade 22, and a relatively thick portion in the form of a planar bus-bar or a blade-carrier 26. The relatively thick and thin portions 20, 26 are integral, the first contactor member 16 being a single unitary piece.

(11) The relatively thick and thin portions 20, 26 are substantially continuous. The relatively thick and thin portions 20, 26 are joined by electron beam welding to form the first contactor member 16.

(12) In the embodiment shown, the switching device 10 is a 60 Amp single pole switching device. However, in other embodiments, similar or like components may be used. For example, the same actuator 12, or at least components thereof, may be used in, for example, a 100 Amp device, or in a 200 Amp two pole device. Features or components may be modified, such as scaled appropriately, to provide embodiments for other ratings, such as 100 Amps. The switching device 10 shown is suitable for low short circuit or high short circuit conditions. The rating may correspond to a nominal load.

(13) The device 10 comprises an insulating housing 28. The actuator 12 comprises an electromagnetic coil 30 with a coil winding 32 and a pair of coil field pieces 34, 36. Here, both the first contactor member 16 and the second contactor member 18 extend through an opening or aperture from within the housing 28 to external to the housing 28. The relatively thick portion 26 extends through one of the openings or apertures from within the housing 28 to external to the housing 28. The first and second contactor members 16, 18 are configured for electrical connection external to the housing 28.

(14) Here, the actuator 12 is a permanent magnet latching actuator. The actuator 12 is configured to actuate the contactor 14 in response to a magnetic field generated by the coil winding 32 and the coil field pieces 34, 36.

(15) The actuator 12 comprises an actuator arrangement with a pivotable actuator member 38 in the form of a rotary actuator member. The pivotable actuator member 38 comprises an overmoulded permanent magnet, with respective pairs of field members 40, 42 for cooperation with the respective coil field pieces 34, 36. The pivotable actuating member is configured to pivot about an axis or pivot 44 in response to a magnetic field generated by the coil winding 32 and the coil field pieces 34, 36. The pivot 44 is arranged to allow the pivotable actuator member 38 to pivot about an axis perpendicular to a central plane of the device 10.

(16) The actuator arrangement comprises a substantially linear actuator member 46 configured to translate substantially linearly. In the embodiment shown, the linear actuator member 46 is guided in the housing 28 to translate substantially perpendicular to the moving blade 22. The actuator arrangement is configured to disconnect and connect a pair of contacts 48, 50 provided in the contactor 14. In the embodiment shown, the contacts 48, 50 are silver-coated or plated. In use, the linear actuator member 46 acts directly on the contactor 14 by engaging the moving blade 22.

(17) In the embodiment shown, the pivotable and linear actuator members 38, 46 are discrete. In other embodiments, the pivotable and linear members may be unitary, such as integrally formed.

(18) The actuator 12 comprises a resilient member 52. The resilient member 52 is configured to apply a compressive force to the linear actuator member 46. The resilient member 52 is configured to bias the actuator towards a particular state or configuration, which is the OFF configuration in the embodiment shown (noting that the OFF configuration is not depicted).

(19) Here, the resilient member 52 comprises a compression coil spring. In other embodiments alternative or additional resilient members or types of resilient members may be provided.

(20) In use, the device 10 is configured to balance forces. As illustrated in FIG. 2, showing a cross-section of the device 10, the device 10 comprises an aligned force transmission system. The device 10 is configured to balance forces transmitted between the actuator 12 and the contactor 14. The device 10 is configured to align contact points of force transmission. The transmission system comprises the coil 30 and the pivotable actuator member 38 and the linear actuator member 46 and the resilient member 52 and the pair of contacts 48, 50 and the contactor members 16, 18.

(21) The device 10 is configured to prevent or at least reduce torsional forces. The device 10 is configured to prevent or at least reduce twisting. The actuator 12 and the contactor 14 are arranged such that force is transmitted between components of the actuator 12 and the contactor 14 substantially in a plane, represented by the broken line 54 in FIG. 2. The plane 54 is substantially perpendicular to the moving blade 22 and the bus-bar 26 of the first contactor member 16 and to the second contactor member 18. In use, the movement of the moving blade 22 is substantially in plane with the force transmission system. The plane 54 comprises a central plane, passing through centroids of the contactor 12 and the actuator 14. In the embodiment shown, the plane 54 passes through a center or central axis of each contactor member 16, 18.

(22) The device 10 is configured to substantially centrally load the force transmission system. A center of the pivotable actuator member 38 is located in the central plane 54. The centroid of the pivotable actuator member 38 is located in the central plane 54.

(23) The device 10 is configured to prevent out of plane forces. The device 10 is configured to substantially transmit all forces in plane 54. The device 10 is configured to prevent pivoting, twisting or torsion of components, such as out of the plane 54. The forces act along the central plane 54 of the device 10. The forces act along a centreline of the device 10.

(24) The actuator arrangement is configured to act upon or transmit force to the first contactor member 16 at a central portion of the contactor member 16. The linear actuator member 46 contacts the moving blade 22 at a central location, equidistant from either edge of the moving blade 22.

(25) The actuator arrangement is configured to force the moving blade 22 towards the ON configuration (e.g. to push). The actuator arrangement is configured to provide a force to the moving blade 22 in the ON configuration to maintain engagement of the contacts 48, 50 between the first and second contactor members 16, 18. The actuator arrangement is configured to force the moving blade 22 towards the OFF configurations (e.g. to pull).

(26) Although not shown, it will be appreciated that the device 10 can be toggled between the ON configuration as shown and the OFF configuration (not shown) by selectively activating the coil 30 to move the linear actuator member 46 relatively up or down to respectively close or separate the contacts 50, 48.

(27) Reference is now made to FIG. 3, showing a detail view of a portion of the actuator 12. The view shows a partial cross-section.

(28) The pivotable actuator member 38 is configured to cooperate with the linear actuator member 46 to convert a substantially rotational force, such as generated by the coil 30, into a substantially linear force. The actuator 12 comprises an interengaging coupling arrangement 56 between the pivotable actuator member 38 and the linear actuator member 46. In the embodiment shown, the linear actuator member 46 comprises a recess and the pivotable actuator member 38 comprises a corresponding protrusion 60, in the form of a lever arm.

(29) The coupling arrangement 56 is configured to eliminate or at least reduce play between the actuator members 38, 46. Here, the coupling arrangement 56 comprises a snug fit in the ON and OFF configurations; and configurations therebetween.

(30) The coupling arrangement 56 is configured to ensure engagement between the actuator members 38, 46. The coupling arrangement 56 is configured to provide full engagement between the pivotable actuator member 38 and the linear actuator member 46 at all times, such as throughout all movements and/or reconfigurations. The coupling arrangement 56 is configured to provide engagement between the pivotable actuator member 38 and the linear actuator member 46 at the same contact points or surfaces at all times. For example the coupling arrangement 56 comprises a first interface for transferring load between the pivotable and linear actuator members 38, 46 in a first direction of movement, such as a first linear direction of movement; and a second interface for transferring load between the pivotable and linear actuator members 38, 46 in a second direction of movement, such as opposite to the first direction of movement. The coupling arrangement 56 ensures engagement at the first and second interfaces at all times. Each interface comprise contact points or surfaces of the actuator members 38, 46. Engagement comprises contact, such as load-bearing contact.

(31) The coupling arrangement 56 is configured to provide a maximum contact surface area between the linear and the pivotable actuation members 38, 46 at or around the initiation of an actuation, such as a connect and/or a disconnect. Providing a maximum contact surface area may reduce pressure for a given force, such as a maximum force and/or a static force. The coupling arrangement is configured to provide a maximum contact surface area between the linear and the pivotable actuation members 38, 46 in a direction of movement at or around the initiation of an actuation, such as a connect and/or a disconnect.

(32) The coupling arrangement is configured to provide a minimum contact surface area between the linear and the pivotable actuation members 38, 46 in the direction of movement at or around the completion of an actuation, such as a connect and/or a disconnect.

(33) The coupling arrangement 56 is configured to vary the location or position of the maximum and/or minimum contact surface area/s between the linear and the pivotable actuation members 38, 46 according to the direction of travel. The coupling arrangement 56 comprises the first interface for transferring load from the pivotable actuator member 38 to the linear actuator member 46 in the first direction of movement. The second interface is for transferring load from the pivotable actuator member 38 to the linear actuator member 46 in the second direction of movement. The first interface is opposite the second interface. The first interface is located on a first side of the pivotable actuator member 38 (e.g. the first side being in the direction of movement in a first stage or portion of actuation); and the second interface is located on a second side of the pivotable actuator member 38 (e.g. the second side being in the direction of movement in a second stage or portion of actuation or of a different actuation or deactuation). The first direction of movement is in a direction of a connect actuation. The second direction of movement is in a direction of a disconnect actuation, or a deactuation.

(34) The coupling arrangement 56 is configured to provide a maximum contact surface area between the linear and the pivotable actuation members 38, 46 opposite the direction of movement at or around the completion of an actuation, such as a connect and/or a disconnect. Providing a maximum contact surface area opposite the direction of movement towards the completion of an actuation may provide for a reliable and/or consistent and/or accurate positioning of the actuation members 38, 46 upon completion of the actuation. In the embodiment shown a relatively large contact surface area 62 is provided in the direction of movement if the linear actuator 46 were to be moved from the ON configuration of FIG. 3 towards an OFF configuration (not shown). The relatively large contact surface area 62 provides a better alignment between the linear and the pivotable actuation members 38, 46; such as compared to the relatively small contact surface area 64.

(35) The protrusion 60 comprises an angular portion, such as a wedge, in the embodiment shown. The angular portion comprises an angle 66 corresponding to an angle of rotation of the pivotable member 38 between configurations, such as between the On and OFF configurations.

(36) The recess 58 and protrusion 60 each comprise a pair of corresponding engagement surfaces. The coupling arrangement is configured to substantially maintain contact between the corresponding engagement surfaces, such as throughout actuation and/or during periods of ON and/or OFF configurations.

(37) The protrusion 60 is substantially parallel to the first contactor member 16, such as to the moving blade 22. The protrusion 60 is substantially parallel to the first contactor member 60 in a neutral configuration, such as midway between the ON and OFF configurations.

(38) Reference is now made to FIG. 4, which shows a side view of a portion of the device 10, including the contactor 14. The device 10 is configured to minimise a net force between the contacts 50, 48 in response to current flowing (e.g. Lorenz force). The device 10 is configured to generate a similar repulsive force between the moving blade 22 and the first bus-bar 26 and between the moving blade 22 and the second bus-bar 18. The moving blade 22 is substantially equidistant the first and second bus-bars 18, 26 (e.g. the moving blade 22 is positioned halfway between and substantially parallel to each of the first and second bus-bars 18, 26). The moving blade 22 is substantially equidistant the first and second bus-bars 18, 26 in at least the ON configuration, as shown in FIG. 4.

(39) The first contactor member 16 comprises a hinge 68 in the form of a U-bend. Accordingly, the first contactor member 16 comprises a U-shape. The hinge 68 comprises a defined bending radius. The radius provides for a predetermined separation of portions of the first contactor member 16 either side of the hinge 68, such as adjacent the hinge. The radius provides for a similar separation of the moving blade 22 from the first and second bus-bars 18, 26. The hinge 68 defines a virtual pivot axis.

(40) At least a part of the relatively thick portion 26 and at least a part of the relatively thin portion 20 are arranged substantially parallel to each other in the OFF configuration. At least a part of the relatively thick portion 26 and at least a part of the relatively thin portion 20 are angularly offset. The moving blade 22 carrying the contact 48 is angularly offset such that the moving blade 22 and the bus-bar 26 diverge away from the hinge 68 in the ON configuration shown in FIG. 4. Here, the angular offset comprises an angle of about 6°.

(41) Reference is now made to FIG. 5, which shows the first contactor member 16 in isolation. In the embodiment shown, the first contactor member 16 comprises a second hinge 70 in the form of a portion of reduced stiffness. The second hinge 70 is configured to reduce a required opening force.

(42) The second hinge 70 comprises a portion of increased flexibility. The second hinge 70 comprises a portion of reduced cross-sectional area relative to the thick and thin portions 20, 26 of the first contactor member 16. Increased flexibility may allow the moving blade 22 to deflect easily, such as to allow the contact 48 mounted to the moving blade to oscillate or rock in use (e.g. to prevent welding of the contacts 48, 50).

(43) Here, the portion of increased flexibility comprises a reduced width, such as a necking or a waisting. The first and second hinges 68, 70 are located proximal or adjacent to each other. The portion of reduced stiffness may be located adjacent the U-bend. Here, both the hinges 68, 70 are located distal to the transition portion 24, and are both located in the relatively thin portion 20. The hinges 68, 70 are located between the relatively thick portion 26 and the contact 48.

(44) The hinges 68, 70 provide for a similar deflection at a reduce force. The hinges 68, 70 provide for an increased deflection at a similar force. The hinges 68, 70 allow for a reduced length of the first contactor member 16.

(45) The hinges 68, 70 are located distal to the contact 48 of the first contactor member 16. The contact 48 is located at or towards a free end of the moving blade 22, the free end of the moving blade 22 being distal to the first hinge 68.

(46) In use, the actuator arrangement transmits force to the moving blade 22 distal to the hinges 68, 70. The actuator arrangement is configured to transmit force to the moving blade at a maximum separation from the first hinge 68. The actuator arrangement is configured to transmit force to the moving blade 22 proximal to the contact 48. The actuator arrangement is configured to transmit force to the free end of the moving blade 22, thus maximising leverage.

(47) Here, the relatively thin portion 20 comprises a thickness, such as a nominal thickness, less than or equal to about 30% of the thickness of the relatively thick portion 26. In other embodiments, other thickness ratios may be provided.

(48) The first contactor member 16 comprises the transition portion 24 between the relatively thick portion 26 and the relatively thin portion 20. The transition portion 24 is configured to provide a smooth transfer between the relatively thick portion 26 and the relatively thin portion 20. The transition portion 24 is configured to provide a smooth transfer of electrical load between the relatively thick portion 26 and the relatively thin portion 20. The transition portion 24 is configured to provide a smooth transfer of mechanical load between the relatively thick portion 26 and the relatively thin portion 20. The transition portion 24 is configured to provide a smooth transfer of thermal load between the relatively thick portion 26 and the relatively thin portion 20.

(49) The transition portion 24 and the relatively thick portion 26 and the relatively thin portion 20 are substantially homogenous. In the embodiment shown, the transition portion 24 and the relatively thick portion 26 and the relatively thin portion 20 comprise a similar material in the form of homogenous copper with similar mechanical and electrical and thermal properties.

(50) In alternative embodiments, devices may appear similar to that shown in the Figures. However, the transition portion and/or the relatively thick portion and/or the relatively thin portion may be substantially dissimilar in at least one property. For example, the transition portion and/or the relatively thick portion and/or the relatively thin portion may comprise dissimilar properties from at least one of the other portions. The dissimilar property/ies may comprise a type of material and/or a mechanical property and/or an electrical property and/or a thermal property. For example, in other embodiments, the contactor member comprises a bimetallic contactor member, such as with copper in the relatively thick portion and a copper alloy (e.g. copper/zirconium alloy or the like) in the relatively thin portion.

(51) The relatively thick portion 26 and the relatively thin portion 20 are axially aligned at the transition portion such that the relatively thin portion 20 is an axial extension of the relatively thick portion 26.

(52) The transition portion 24 comprises a chamfer. The transition portion 24 is configured to prevent peeling of the relatively thin portion 20 from the relatively thick portion 26. The first contactor member 16 is configured to substantially tensionally or compressively load the transition portion 24.

(53) The transition portion 24 is comprises a fused portion, formed by electron beam welding. In the embodiment shown, the transition portion 24 comprises a lap connection between the relatively thin portion 20 and the relatively thick portion 26. In other embodiments, the transition portion comprises a butt connection, such as a butt fusion.

(54) The device 10 is configured to allow the actuator 12 to act directly on a central portion of the first contactor member 16. The device 10 is configured to allow the actuator arrangement to act directly on the moving blade 22. The first contactor member 16 comprises a slot or opening 72 to allow the actuator arrangement to pass through. The opening 72 is centrally located in the contactor member 16. The opening 72 allows the actuator arrangement to pass through centrally. The opening 72 allows the aperture arrangement to transmit force to the first contactor member 16 substantially linearly, with the linear actuator member 46. The opening 72 allows the linear actuator member 46 to transmit force internally centrally. The opening 72 allows the linear actuator member 46 to transmit force directly to the moving blade 22. The opening 72 allows the linear actuator member 46 to be substantially purely compressively or tensionally loaded.

(55) Reference is now made to FIGS. 5 and 6. FIG. 6 shows the second contactor member 18 in isolation. The first and second contactor members 16, 18 are configured to dissipate heat at an increased rate.

(56) The first and second contactor members 16, 18 comprise increased surface areas. The first and second contactor members 16, 18 comprise surface areas of at least one side or face 74, 76 that are substantially greater than the footprint and/or planar projection of said side or face 74, 76.

(57) The surface areas of the at least one side or face 74, 76 are substantially discontinuous. The surface areas of the at least one side or face 74, 76 are configured to dissipate substantially more heat than an equivalent continuous or planar surface. The first and second contactor members 16, 18 comprise non-uniform and non-homogenous and asymmetrical and anisotropic cross-sections at at least one portion.

(58) The first and second contactor members 16, 18 comprise a plurality of recesses 78, 80 longitudinally and laterally arranged along and perpendicular to a longitudinal axis of the contactor member, in the at least one side or face 74, 76. In the embodiment shown, the recesses 78, 80 comprise blind recesses, in the form of indentations or depressions. In other embodiments, the recess comprises a continuous recess. For example, the recess comprises a continuous slot, such as a serpentine or a labyrinthine slot. In other embodiments, the contactor member/s comprise protrusions in addition or alternatively to recesses.

(59) In the embodiment shown, cross-sections of the first and second contactor members 16, 18 comprise a variable thickness, such as parallel and perpendicular to a longitudinal axis of the contactor members 16, 18. The recesses 78, 80 do not have corresponding protrusions in faces opposing the increased surface area faces 74, 76.

(60) Here, each contactor member 16, 18 comprises an internal portion within the housing 28 and an external portion outside the housing 28. The relatively thick portion 26 comprises internal and external portions. The internal and external portions are configured to dissipate heat at the increased rate. The internal and the external portions of the first and second contactor members 16, 18 comprise the sides or faces 74, 76 with the surface area that is substantially greater than the footprint and/or planar projection of said side or face 74, 76.

(61) In the embodiment shown the second contactor member 18 comprises a static contactor member in the form of a fixed bus-bar. In other embodiments, the second contactor member is substantially similar to the first contactor member 16; such as comprising a bus-bar 26 and a moving blade 22.

(62) Here, the switching device 10 comprises a remote disconnect switching device, such as a remotely-operable or remotely-operated disconnect switching device. The switching device 10 comprises a disconnect relay, such as for a smart meter. The switching device 10 comprises a switching device for connecting and/or disconnecting a power load from a voltage source, such as from AC mains electricity. The switching device 10 comprises a high current switching device. The switching device 10 is configured to withstand a short circuit load, such as thirty times the nominal load. The switching device 10 comprises a domestic or residential electricity switching device. The switching device 10 comprises a cyclical switching device, rated and/or suitable for at least 5000; at least 10000; at least 15000 operating cycles respectively, such as electrically operating cycles.

(63) Other switching devices may be suitable for kiloampere loads; such as for 6000 Amps or more. Other switching devices comprise an industrial electricity switching device. Other switching devices comprise a DC switching device, such as for low voltage sources (e.g. for vehicle batteries).

(64) It will be appreciated that any of the aforementioned apparatus may have other functions in addition to the mentioned functions, and that these functions may be performed by the same apparatus.

(65) The applicant hereby discloses in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. The applicant indicates that aspects of the present invention may consist of any such individual feature or combination of features. It should be understood that the embodiments described herein are merely exemplary and that various modifications may be made thereto without departing from the scope of the invention. For example, it will be appreciated that although shown here as continuous, the moving blade may comprise a bifurcation/s. Although shown hear as planar, other embodiments of contactor member may be curved, such as convex and/or concave.