Abstract:
A lever electromechanical valve actuator assembly and arrangement of electromechanical valve actuators that creates a compact actuator assembly to increase ease of serviceability, provide space for engine components and eliminate interference between the actuators and components in the vehicle engine compartment.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a continuation-in-part of U.S. patent application Ser. No. 10/963,892, filed Oct. 13, 2004 which claims the benefit of U.S. Provisional Application No. 60/510,988, filed Oct. 14, 2003, the entire disclosure of each application is considered part of the disclosure of this application and is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to electromechanical valves actuators and, more particularly, to compact electromechanical valve actuator assemblies and the arrangement of electromechanical valve actuators on an engine.  
         [0003]     As engine technology advances and manufacturers strive to increase engine power, improve fuel economy, decrease emissions, and provide more control over engines, manufacturers are developing electromechanical valve actuators (also known as electromagnetic valve actuators or EMVA) to replace cam shafts for opening and closing engine valves. Electromechanical valve actuators allow selective opening and closing of the valves in response to various engine conditions.  
         [0004]     Electromechanical valve actuators generally include two electromagnets and a spring loaded armature plate disposed between the electromagnets. The armature plate is movable between the electromagnets as the power coils are selectively energized to create a magnetic force to attract the armature plate to the energized electromagnet. The surface of the electromagnets to which the armature is attracted is generally referred to as a pole face, and the armature is operationally coupled to the valve so that as the armature moves between pole faces in a pole-face-to-pole-face operation, the valve is opened and closed.  
         [0005]     Electromechanical valve actuators are generally formed as linear electromechanical valve actuators or lever electromechanical valve actuators. One problem with linear electromechanical valve actuators is that each linear electromechanical valve actuator operationally coupled to the associated valve includes a relatively large set of electromagnets for opening and closing the valves ( FIG. 1 ). The size of the electromagnets makes it difficult to position all of the linear electromechanical valve actuators over a particular cylinder, especially for engines that have four or more valves per cylinder. The size of linear electromechanical valve actuators may also limit the ease of serviceability of the engine, such as restricting the space available for changing the spark plug. Another problem with linear electromechanical valve actuators is that linear electromechanical valve actuators generally have a substantial height extending from the cylinder head of an engine. The height of the linear electromechanical valve actuators creates difficulty in packaging the linear actuators on engines in today&#39;s compact engines and in today&#39;s full engine compartments. For example, linear electromechanical valve actuators may interfere with other engine parts, other components or accessories located in the engine compartment, and even the vehicle body, such as, the hood. Yet another problem with linear electromechanical valve actuators is that they generally draw a substantial amount of power from the vehicle&#39;s electrical system, as compared with lever electromechanical valve actuators, thereby putting additional demand on the alternator in today&#39;s power hungry vehicles.  
         [0006]     In view of the drawbacks associated with linear electromechanical valve actuators, many manufacturers have recently turned to lever electromechanical valve actuators, which, due to their mechanical and magnetic properties, generally have substantial power savings over linear electromechanical valve actuators. Lever electromechanical valve actuators also generally do not protrude as far from the cylinder head as linear electromechanical valve actuators. However, a major problem with lever electromechanical valve actuators is still the package size required on the cylinder head. Due to the set locations of valves and spark plugs by engine designers, designs for lever electromechanical valve actuator assemblies on the engine have been traditionally limited. Most lever electromechanical valve actuators packaged on the cylinder head are arranged longitudinally in line with the elongated longitudinal cylindrical head extent of the cylinder head, as shown in  FIG. 2 . Therefore, each actuator group within the actuator assembly, and associated with a particular cylinder, is arranged laterally across the cylinder head with each individual actuator being arranged longitudinally with the cylinder head. More specifically, the pivot axes of each actuator aligned with the cylinder head longitudinal extent. As shown in  FIG. 2 , the lever electromechanical valve actuators on an engine having four valves  20  per cylinder  16  require significantly more space across a cylinder head than camshafts, thereby presenting packaging concerns in engine compartments where space is limited. Also, the arrangement of lever electromechanical valve actuators shown in  FIG. 2  raises additional serviceability concerns, especially for the ease of servicing and replacing the spark plugs and in some arrangements, the space available for fuel injectors. The difficulty in changing the spark plug as well as servicing the actuators is compounded in that at least two of the actuators are completely within the perimeter of the cylinder walls extended toward the actuators. Therefore, there is a need for additional electromechanical valve actuator arrangements that minimize package space, provide ease of serviceability, and provide room for wiring assemblies and control modules communicating with the individual actuators.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention relates to electromechanical valve actuators and, more particularly, to compact electromechanical valve actuator assemblies and the arrangement of electromechanical valve actuators on an engine.  
         [0008]     Careful arrangement of electromechanical valve actuators to create a compact assembly increases ease of serviceability, provides space for access to various engine components such as the spark plug, provides additional package space for wiring harnesses and control modules of electromechanical valve actuators, and eliminates potential interference between the actuators and components in the vehicle engine compartment or the vehicle body.  
         [0009]     The present invention is directed to a lever electromechanical valve actuator assembly for a vehicle engine having cylinders and a cylinder head with a longitudinal cylinder extent, the cylinder head being disposed between the lever electromechanical valve actuator assembly and the cylinders. The electromechanical valve actuator assembly includes a first actuator having a first pivot axis, and a second actuator having a second pivot axis. The first and second pivot axes are each approximately within forty five degrees of perpendicular to the longitudinal cylinder extent.  
         [0010]     In another embodiment, the present invention is directed to a lever electromechanical valve actuator assembly for a vehicle engine having cylinders and a cylinder head defining spark plug holes and having a longitudinal cylinder head extent, the cylinder head being disposed between the lever electromechanical valve actuator assembly and the cylinders. The electromechanical valve actuator assembly includes a first actuator having a first pivot axis approximately aligned between two adjacent spark plug holes and approximately aligned with the longitudinal cylinder head extent.  
         [0011]     In yet another embodiment, the present invention is directed to a lever electromechanical valve actuator assembly for a vehicle engine having cylinders and a cylinder head with a longitudinal cylinder head extent, the cylinder head being disposed between the cylinders and the electromechanical valve actuator assembly. The electromechanical valve actuator assembly includes a first actuator having a first core and a first power coil, and a second actuator having a second core and a second power coil. Each of the power coils form an end turn on at least one end of each of the first and second cores. The end turns extend a distance beyond the at least one end of each of the first and said second cores and wherein the first core and the second core are arranged so that the first core and the second core are displaced less than two times said distance apart.  
         [0012]     Further scope of applicability of the present invention will become apparent from the following detailed description, claims, and drawings. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The present invention will become more fully understood from the detailed description given here below, the appended claims, and the accompanying drawings in which:  
         [0014]      FIG. 1  is a prior art top plan view of the placement of linear electromechanical valve actuators over cylinders;  
         [0015]      FIG. 2  is a prior art top plan view of the lever electromechanical valve actuators over cylinders;  
         [0016]      FIG. 3  is a top plan view of a lever electromechanical valve actuator assembly on a cylinder head;  
         [0017]      FIG. 4  is a cross-sectional view along lines  4 - 4  in  FIG. 3 ;  
         [0018]      FIG. 5  is a top plan view of a first alternative lever electromechanical valve actuator assembly arrangement on a cylinder head;  
         [0019]      FIG. 6  is a top plan view of a second alternative lever electromechanical valve actuator assembly arrangement on a cylinder head;  
         [0020]      FIG. 7  is a top plan view of a third alternative lever electromechanical valve actuator assembly on a cylinder head;  
         [0021]      FIG. 8  is an enlarged top plan view of a portion of the actuator assembly in  FIG. 7 ;  
         [0022]      FIG. 9  is a top plan view of a fourth alternative lever electromechanical valve actuator assembly on a cylinder head;  
         [0023]      FIG. 10  is a top plan view of a fifth alternative lever electromechanical valve actuator assembly on a cylinder head wherein a pair of actuators are coupled together;  
         [0024]      FIG. 11  is a top plan view of a sixth alternative lever electromechanical valve actuator assembly on a cylinder head;  
         [0025]      FIG. 12  is a top plan view of a seventh alternative lever electromechanical valve actuator assembly on a cylinder head;  
         [0026]      FIG. 13  is a top plan view of an eighth alternative lever electromechanical valve actuator assembly on a cylinder head;  
         [0027]      FIG. 14  is a top plan view of the lever electromechanical valve actuator assembly on a cylinder head with only intake actuators;  
         [0028]      FIG. 15  is a top plan view of the second alternative electromechanical valve actuator assembly on a cylinder head with only intake actuators. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0029]     A lever electromechanical valve actuator assembly shown generally at  10  in  FIG. 3  is mounted on a cylinder head  80  of an internal combustion engine  12  and with individual actuators  2 ,  4  being at least partially located over an associated cylinder  16 . The actuators  2 ,  4  operably associated with a particular cylinder  16  may be referred to as actuator groups  11 . Each actuator  2 ,  4  of the lever electromechanical valve actuator assembly  10  is connected to a valve  20 , such as an intake or exhaust valve, to open and close the valve  20  as desired. The electromechanical valve actuator assembly  10 , as illustrated in  FIG. 3 , and as illustrated in the alternative embodiments shown in  FIGS. 5-15 , provides a more compact arrangement while allowing greater serviceability and easier assembly.  
         [0030]     The electromechanical valve actuator assembly  10  generally includes both intake actuators  2  and exhaust actuators  4  as illustrated in  FIGS. 3 and 4 - 13 . Of course, the actuator assembly  10  may include only intake actuators  2  as illustrated in  FIGS. 14 and 15 , only exhaust actuators (not shown), or a combination of the illustrated and claimed embodiments varying by cylinder or by intake or exhaust sides. For example, one actuator assembly may be suited for the intake side while another actuator assembly may be better suited for the exhaust side, or different actuator assemblies may be used for different cylinders depending on engine configuration and packaging needs.  
         [0031]     The actuators  2 ,  4  each include an armature assembly shown generally at  30  having an armature plate  32  and a connecting rod  90 , an electromagnet assembly shown generally at  70  having electromagnets  72 ,  74 , and a spring assembly shown generally at  60 . The armature plate  32  is alternatively attracted to the electromagnets  72 ,  74 , thereby applying force to the spring assembly  60  and valve  20  through the connecting rod  90  to open and close the valve  20 . While the actuators  2 ,  4  are illustrated as having a connecting rod  90 , the actuators may be formed without the use of a connecting rod. Further, any lever electromechanical valve actuator configuration, shape, or assembly may be substituted for the illustrated electromechanical valve actuators in the figures, as the present invention is primarily directed to the arrangement of the electromechanical valve actuators  2 ,  4  relative to each other, relative to the cylinder head  80 , and relative to the cylinders  16 .  
         [0032]     The valve  20  is similar to traditional valves and generally includes a valve head  22  with a valve stem  24  extending therefrom. The valve  20  has an opened and closed position and is illustrated in  FIG. 4  in the closed position. In the closed position, the valve head  22  seals a valve port  14  to the corresponding cylinder  16 . The valve port  14  may be an exhaust port or intake port and the actuator  2 ,  4  operably controlling the valve  20  associated with the exhaust valve port is the exhaust actuator  4  and the valve  20  associated with the intake port is controlled by the intake actuator  2 . As shown in  FIG. 8 , the valve  20  generally moves along a valve axis  26  between the open and closed positions.  
         [0033]     The electromagnet assembly  70  controls the movement of the armature assembly and thereby the movement of the valve  20 . The electromagnets  72 ,  74  are generally secured to c-blocks  8 ,  9  which are in turn secured to the cylinder head  80 . A housing plate  6  may operably couple a pair of actuators together for ease of assembly, as illustrated in  FIG. 10 . The housing plate  6 , if used, may include a recess  105  to provide sufficient room for accessing the spark plug.  
         [0034]     The armature assembly  30  includes the armature plate  32  and the connecting rod  90 . The armature plate  32  pivots about a pivot axis  44  near a pivot end  49  of the armature plate  32  to open and close the valve  20 . The connecting rod  90  is coupled to or driven by the armature plate  32 . The armature plate  32  further includes a lever end  48  which is opposite the pivot end  49 . While any electromechanical valve actuator may be used in the present invention to create the lever electromechanical valve actuator assembly  10 , the electromechanical valve actuators  2 ,  4  described above and illustrated in  FIG. 4  provide further space savings and further facilitate the arrangement of the electromechanical valve actuators. Further, by locating the actuator so that the valve  20  is inward of the lever end  48 , additional space savings may be realized.  
         [0035]     To facilitate the description of the electromechanical valve actuator assembly  10  and the specific arrangement of the actuators  2 ,  4  relative to each other, the geometry and directional arrangement such as longitudinal and lateral extents of the cylinder head  80 , the cylinder  16 , and the actuators  2 ,  4  must first be described. The internal combustion engine  12  includes a desired number of cylinders  16 . The cylinders  16  may be arranged in any shape or configuration possible for the operation of an internal combustion, such as an in-line four cylinder engine or a V-6 engine. The cylinders  16  each include a cylinder axis  18  along which the piston  15  travels. Cylinders  16  also include a perimeter wall  17 . In this application and in the claims, when the perimeter is referred to as being extended toward the actuators  2 ,  4  or the extended perimeter, that description generally refers to not the actual extent of the perimeter  17  defined by the cylinder walls but a theoretical or virtual extension of the perimeter of the cylinder walls, beyond where the cylinder wall perimeter  17  actually stops when it meets the cylinder head  80 , toward the actuators  2 ,  4 . The cylinders  16  may further be described as being arranged along a cylinder longitudinal extent  19 , which is generally along a longitudinal extent of the engine or parallel to a longitudinal extent of the engine, specifically along a line drawn through the axes  18  of the cylinder  16 . The cylinder head  80  also includes a longitudinal extent  86  that generally corresponds to the direction in which the cylinder longitudinal extent  19  extends and a cylinder head lateral extent  84 , which is generally perpendicular to the cylinder longitudinal extent  19 . The cylinder head  80  also defines spark plug holes  88 , and is generally banked, as best illustrated in  FIG. 4 .  
         [0036]     The actuators  2 ,  4  generally include a longitudinal actuator extent  52  which is generally aligned with the pivot axis  44  and a lateral actuator extent  54  which is somewhat perpendicular to the pivot axis  44  ( FIGS. 3 and 5 - 13 ). The actuators  2 ,  4  may also include a longitudinal actuator center  58 , which is approximately the center of the longitudinal actuator extent  52 , and a lateral actuator center  56  which is approximately the center of the lateral actuator extent  54 . As illustrated in  FIG. 7 , due to the bank of the actuator, the longitudinal center may be viewed as an angled plane. The longitudinal actuator center  58  is illustrated as different between the top and bottom of the actuators, even though each of the lines is at the longitudinal center  58  due to the angle of view from which the figure is illustrated.  
         [0037]     In the primary embodiment, illustrated in  FIG. 3 , the lever electromechanical valve actuator assembly  10  is arranged so that intake actuators  2  are arranged so that the pivot axes  44  are approximately perpendicular to the cylinder head longitudinal extent  86 . More specifically, the longitudinal actuator extent  52  is arranged approximately perpendicular to the cylinder head longitudinal extent  86 . Therefore, as illustrated in  FIG. 3 , the actuators  2 ,  4  are arranged on the cylinder head  80  in a lateral configuration, wherein the intake actuators  2  are approximately aligned along their longitudinal extent and laterally relative to the cylinder longitudinal extent  86 . The exhaust actuators  4  are also approximately aligned along their longitudinal extent and laterally relative to the cylinder longitudinal extent  86 . In this arrangement and as illustrated in  FIG. 3 , the pivot end  49  of one actuator is arranged in closer proximity to the lever end  48  of the adjacent actuator over the same cylinder  16 , than the pivot end  49  of one actuator is in proximity to the pivot end  49  of the adjacent actuator. The arrangement of the pivot end  49  being in close proximity to the lever end  48  of the adjacent actuator arranges the actuators so that the actuators are oriented in the same direction and that the pivot end  49  of one actuator is closer to the lever end  48  of the adjacent actuator than the pivot end  49  of adjacent actuator. Further, as illustrated in  FIG. 3 , the intake actuators  2  all face the same direction and if included, as shown in  FIG. 3 , the exhaust actuators also face the same direction. Of course, the intake actuators  2  may all face the same direction while the exhaust actuators  4  all face the same direction, but opposite the direction of the intake actuators  2  (not shown). As further illustrated in  FIG. 3 , the pivot axes  44  of the intake actuators  2  are substantially parallel and the pivot axes  44  of the exhaust actuators  4  are also parallel, although not necessarily parallel to the intake actuators  2 . As further illustrated in  FIGS. 3 and 4 , the pivot axes  44  of the intake actuators  2  and the exhaust actuators  4  are generally angled relative to each other due to the angled arrangement of the valves  20  and the banking of the cylinder head  80 . Therefore, even though the intake actuators  2  may be aligned along the cylinder head longitudinal extent  86  with an exhaust actuators  4 , such that the pivot axes  44  of an intake actuator  2  is aligned along the longitudinal extent  86  with a pivot axis  44  of an exhaust actuator  4 , the pivot axes  44  are generally angled relative to each other.  
         [0038]     As further illustrated in  FIG. 3 , the connecting rod  90  which is coupled to the valve  20  is connected to approximately the center of the longitudinal actuator extent  52 , or along the longitudinal actuator center  58 . However, the connecting rod  90  may be coupled to a position on the actuators  2 ,  4  which is offset from the longitudinal actuator center  58 . This offset configuration may allow greater serviceability of the engine and easier access to the spark plug hole  88  defined by the cylinder head  80 .  
         [0039]     In the illustrated embodiment, the actuator assembly  10  is arranged over the cylinders  16 . As shown in  FIGS. 3 and 5 - 13 , if the cylinder outer perimeter  17  is extended toward the actuators  2 ,  4 , each of the lever electromechanical valve actuators  2 ,  4  is located at least partially outside the extended perimeter.  
         [0040]     In the first alternative embodiment illustrated in  FIG. 5 , the actuator assembly  10  is also arranged such that the pivot axes  44  are parallel. More specifically, in the first alternative embodiment, the intake actuators over a particular cylinder  16  are arranged such that they are opposing the adjacent intake actuator. Therefore, the adjacent actuators over a particular cylinder  16  are arranged such that the lever ends  48  are closer together than the lever end  48  of a particular actuator is to its pivot end  49 . As illustrated in  FIG. 5 , the intake actuators over a particular cylinder  16  are offset relative to each other. Further, the exhaust actuators  4  in the illustrated embodiment are offset approximately the same amount so that one pair of intake and exhaust actuators  2 ,  4  is laterally aligned along the cylinder longitudinal extent  86  while the other pair is also aligned along the cylinder longitudinal extent  86 . More specifically, each of the intake and exhaust actuators  2 ,  4  are offset relative to the adjacent actuator  2 ,  4  on the same cylinder  16  along their longitudinal actuator extent. Although the valve  20  and connecting rod  90  are illustrated as being approximately centered along the longitudinal actuator extent  52 , the valve coupled to the actuators  2 ,  4  may be offset from the longitudinal actuator center  58 . Further, in this embodiment each one of the actuators  2 ,  4  is at least partially located outside the extended outer perimeter wall  17  of the cylinder  16 . With the perimeter  17  extended toward the actuators  2 ,  4 , the area within the extended perimeter  17  is less than half filled by the actuators  2 ,  4 , providing substantial room on the cylinder head  80  between the actuators  2 ,  4  for serviceability.  
         [0041]     The second alternative embodiment illustrated in  FIG. 6  further provides serviceability by increasing the area around the spark plug hole  88  on the cylinder head  80  to create a spark plug access area  106 . The arrangement illustrated in  FIG. 6  is similar to the arrangement in  FIG. 5 , except that the actuators  2 ,  4  are shifted in one direction along the cylinder head longitudinal extent  86 , with the valve  20  coupled to actuators  2 ,  4  shifted to one side.  
         [0042]     The third alternative embodiment as illustrated in  FIGS. 7 and 8 , the valve  20  may be located approximately near the center of the actuator and therefore near the center of the armature plate  32  and therefore approximately near the longitudinal actuator center  58  and lateral actuator center  56 . The third alternative embodiment is very similar to the embodiments shown in  FIGS. 5 and 6 , with the actuators  2 ,  4  being adjacent to each other and with each actuator being at least partially disposed outside the extended perimeter  17 . Similar to the second embodiment, the actuator assembly  10  in the third alternative embodiment is arranged such that the pivot axes  44  are parallel. However, as compared to the second alternative embodiment the pivot axes  44  as illustrated in  FIGS. 7 and 8  are arranged such that they extend laterally across the cylinder head  80 . Therefore, the pivot axes  44  are arranged similar to the assembly in  FIG. 3 , except that the actuators individually are arranged such that the lever ends  48  are closer together than the lever end  48  of a particular actuator  2 ,  4  is to its pivot end  49  or to the pivot end of the adjacent actuator. The relative closeness of two adjacent pivot ends  49  or two adjacent lever ends  48  may vary as needed. The actuators  2 ,  4  are illustrated as being independently arranged on the cylinder head  80  although, as illustrated in the fifth alternative embodiment in  FIG. 10 , the actuators may be attached to a common housing plate  6  to be coupled as a unit to the cylinder head  80  for ease of assembly. In place of a common housing plate  6 , a common housing holding the actuators as a unit such as an extended c-block (not shown) may also be used to couple the actuators of a particular cylinder together.  
         [0043]     As further illustrated in  FIG. 8 , the valve stem  24  extending from the valve may be arranged relative to a line  40  extended between the bolt centers of the bolt holes  38  of the actuators. The line  40  may cross the axis or perimeter of the valve stem extended toward the line  40 . Aligning the line  40  between the bolts approximately over the valve stem distributes clamping loads along a line that contains the load associated with the valve stem and connecting rod  90 . Although not required, it may be beneficial to make the axis of the valve stem  24  approximately perpendicular to the line  40 . As illustrated in  FIG. 8 , the actuators may further include a bolt slot  34  allowing ease of assembly on various engines with different bolt patterns.  
         [0044]     In the fourth alternative embodiment, as illustrated in  FIG. 9 , the actuators may be shifted so that actuators on adjacent cylinders are in closer proximity than the actuators operationally over a particular cylinder. This shift as compared to the third alternative embodiment illustrated in  FIGS. 7 and 8  allows more room above the spark plug hole  88 , thereby providing a larger spark plug access area  106 . Although not illustrated, in some embodiments the actuators over adjacent cylinders may be coupled in a common housing for ease of assembly. The sixth alternative embodiment illustrated in  FIG. 11  is also similar to the fourth alternative embodiment illustrated in  FIG. 9 , except that in the sixth alternative embodiment, the adjacent actuators over adjacent cylinders share a pivot axis  44  so that the armature plate  32  of adjacent actuators each being associated within a different cylinder pivot about the same axis. Although not illustrated, it should be relatively apparent to one skilled in the art based upon the illustration in  FIG. 11  that the adjacent actuators may share the same hinge pin. Therefore, as illustrated in  FIG. 11 , the pivot ends of adjacent actuators over adjacent cylinders are not only closer in proximity than the lever ends of adjacent actuators over the same cylinder, but the pivot ends overlap and extend within the adjacent armature plate  32 . This overlapping of the pivot ends  49  allows the actuators to be associated in closer proximity, thereby allowing the actuator assembly  10  to be placed on a more compact cylinder head  80 .  
         [0045]     The seventh alternative embodiment illustrated in  FIG. 12  is similar to the third alternative embodiment illustrated in  FIG. 6 . As illustrated in  FIG. 12 , the actuators  2 ,  4 , as well as the armature plate  32 , include a protrusion  36  which is coupled to the valve  20 . By coupling the valve  20  to the protrusion  36 , various arrangements may be used, allowing a more compact actuator assembly  10 . As shown in  FIG. 12 , by shifting the actuators along the longitudinal actuator extent  52  relative to each other and along the longitudinal cylinder head extent  86 , the actuators may be brought in closer proximity to each other. However, the actuators in close proximity to each are generally actuators operationally associated with adjacent cylinders  16 . Even though not illustrated, the actuators may be longitudinally aligned. The embodiment illustrated in  FIG. 12  also provides a wide area A to receive a control module (not illustrated).  
         [0046]     An eighth alternative embodiment is illustrated in  FIG. 13 . In  FIG. 13 , the actuators are arranged such that the end turn  77  of a power coil  76  exiting a core  78  is disposed in close proximity to the adjacent actuator&#39;s core  78 . The power coils  76  exit the core  78  on one end and turn back into the core  78  on the same end to create an end turn  77 . The end turn  77  of the power coil  76  requires a minimum distance  75  from the end of the core  78  of the actuator in order to make a loop back into the core  78 . Typically, the actuators, specifically the cores  78 , must be spaced at least two times the minimum distance required by the coil  76  to make the end turn  77  to provide sufficient spacing. Therefore, the actuators are arranged in an offset manner both laterally and longitudinally along a cylinder head  80  such that the actuators are spaced apart less than the two times the distance required for end turn  77 . In the embodiment illustrated in  FIG. 13 , careful placement of the actuators on the cylinder head  80  and relative to the cylinder  16  allows the actuators to be placed in closer proximity between two adjacent cores  78  than two times the distance  75  required for the end turn  77  of the power coil  76 . As illustrated in  FIG. 13 , the actuators may be placed within approximately the distance  75  required for one end turn  77  of the coil  76  from the core. Therefore, the cores  78  are in close proximity, allowing better placement of the valves relative to the actuators as well as providing plenty of spark plug access area  106 .  
         [0047]     The remaining actuator assemblies in  FIGS. 14 and 15  illustrate how the actuators may just be used for the intake side of a cylinder head or the exhaust side.  
         [0048]     The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.