ELECTROMECHANICAL VALVE ACTUATOR

CROSS-REFERENCE TO RELATED APPLICATION

This application claims benefit to U.S. Provisional Application Serial No.

60/605,660 filed August 30, 2004, and entitled "3D Depiction of Prototype

Electromechanical Valve Actuator," incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

This invention relates generally to valve devices. More particularly, this

invention relates to an electromechanical valve actuator which utilizes a piston

assembly incorporating magnets.

BACKGROUND AND SUMMARY OF THE INVENTION

Improvement is desired in the field of valves, particularly in regard to

valves for use with internal combustion engines. Conventional engine valves have

undesirable friction and other sources of energy loss. The disclosure relates to an

improved valve system that is particularly configured for use with internal combustion

engines. The valve system advantageously eliminates the need for valve springs and

other mechanical resistance components associated with conventional valves.

In a preferred embodiment, the valve system provides a valve system for

an internal combustion engine. The valve system includes an actuator assembly having

a plurality of coil assemblies arranged in a substantially stacked configuration. Each

coil assembly includes a support made of an electrically insulative material, an

electrically conductive coil positioned about the support and placeable in electrical

communication with a source of electrical power, and a magnetic material substantially

surrounding the electrically conductive coil.

A piston assembly is also provided and includes a non-magnetic plunger

and a plurality of magnets and flux conduits arranged in a substantially stacked and

alternating configuration on the plunger. A valve member is attached to the piston

assembly.

The piston assembly and the valve member are receivable within the

actuator assembly. The coil assemblies are desirably energized by the source of

electrical energy to enable incremental travel of the valve member between positions

corresponding to open and closed positions during a combustion cycle of an internal

combustion engine.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of preferred embodiments of the invention will become

apparent by reference to the detailed description of preferred embodiments when

considered in conjunction with the figures, which are not to scale, wherein like

reference numbers, indicate like elements through the several views, and wherein,

FIG. 1 is a perspective view of a electromechanical valve actuator in

accordance with a preferred embodiment.

FIG. 2 is an exploded view of the assembly of FIG. 1.

FIQ. 3 is an exploded view of a piston component of the assembly of

FIGS, l and 2.

FIG.4 is an exploded view of a coil component of the assembly of FIGS.

1 and 2.

FIG. 5 is a partial cutaway view of the coil component of FIG. 4.

FIG. 6 is a partial cutaway view of an alternative embodiment of a coil

component.

DETAILED DESCRIPTION

With initial reference to FIGS. 1 and 2, there is shown a valve system 10

particularly configured for use with internal combustion engines. The valve system 10

preferably includes, as major components, an actuator assembly 12 including a plurality

of coil assemblies 14, 16, and 18, a piston assembly 20, and a valve 22.

The piston assembly 20 attaches to the valve 22. The coil assemblies 14-

18 are configured to receive the valve 20 and piston assembly 22. The coil assemblies

14-18 are desirably energized to enable incremental travel of the valve 22 between

positions corresponding to the open and closed positions during a combustion cycle of

an internal combustion engine.

With reference to FIG. 3, the piston assembly 22 preferably includes a

non-magnetic plunger 24 having a base 26 and a shaft 28. A plurality of ring magnets

30 and a plurality of flux conduits 32 are positioned in alternating stacked fashion

along the shaft 28 and maintained in position by a non-magnetic retainer 34. The

plunger 24 and the retainer 34 are preferably made of brass or the like. Each of the ring

magnets 30 may be a single magnet or a plurality of thinner ring magnets stacked to

provide the desired thickness.

In a preferred embodiment, the desired thickness is about 0.250 inches.

In this regard, the ring magnets 30 are preferably provided by rare earth magnets and

preferably have an inner diameter of about 0.375 inches and an outer diameter of about

0.75 inches. The flux conduits 32 are preferably steel rings dimensioned similar to the

magnets. The plunger 24 is preferably sized to function as a bearing surface on the

inside of the actuator assembly 10. Thus, the magnets and the flux conduits are

provided on the plunger in a configuration to avoid excessive frictional interference

during movement thereof in operation.

With reference to FIGS.4 and 5, there is shown an exploded view of the

coil assembly 14, but with a magnetic material removed. It will be understood that the

coil assemblies 16 and 18 are preferably identical to the coil assembly 14.

The coil assembly 14 preferably includes a center support 40 in the form

of a cylinder made of an electrically insulative material, such as a plastic material, most

preferably polyvinyl chloride (PVC). A pair of washer shaped inner walls 42,

preferably made of the same material as the center support 40, are preferably secured

adjacent opposite ends of the center support 40, as by adhesive.

An electrically conductive coil 44, preferably made of copper wire, is

wound on a bobbin structure provided by the center support 40 and the walls 42.

Opposite ends of the copper wire preferably extend from the coil 44 to serve as

electrical leads 46. Once the coil 44 is provided on the support 40, a protective coating,

such as epoxy, is preferably applied to the windings of the coil 44 to protect it from

contamination from magnetic material and the like.

A shell 50 and one of two outer walls 52 are next installed around the

center support and coil assembly as shown in FIG. 5, with the wall 52 secured to the

shell 50 as by use of adhesive. The shell 50 and the walls 52 are made of electrically

insulative material, preferably the same material as used for the center support 40 and

the inner walls 42. The leads 46 pass through apertures provide through the shell 50

and are preferably electrically insulated.

Magnetic material 54 is supplied within the annular space between the

center support 40 and the shell 50. For example, iron filings may be used to provide

the magnetic material 54, and the second outer wall 52 installed to provide structure

to retain the magnetic material 54 in place.

Alternatively, and withreference to FIG.6, the magnetic material 54 may

be provided as by a high permeability anisotropic magnetic material provided in pre¬

formed toroids 60, each preferably having an epoxy or other protective coating. In

such case, the toroid 60 adjacent the coil 44 is preferably slit as at 62 to enable passage

of the leads 46.

In operation, electrical energy is applied to the leads 46 of the system 10

as by direct current supplied from a battery operatively associated with a

controller/drive unit. The ^' controller/drive unit is operatively associated with a

crankshaft position sensor to supply position information which may be utilized by the

controller/drive unit to provide desired phasing or firing of the system 10. As will be

appreciated, the desired firing is dependent upon the number of cylinders, duration of

opening, and lift required. The controller/drive unit is preferably microprocessor

controlled and generates a firing pulse for each valve of the combustion engine.

Accordingly, each valve will include a drive circuit or amplifier or the like to supply

a desired current to operate the valve as well as to hold the valve in place when not in

motion.

The valve system advantageously eliminates the use of valve springs and

other mechanical force components and substantially reduces mechanical resistance

and the like so as to eliminate many of the energy losses associated with the operation

of conventional engine valves.

The foregoing description of certain exemplary embodiments of the

present invention has been provided for purposes of illustration only, and it is

understood that numerous modifications or alterations may be made in and to the

illustrated embodiments without departing from the spirit and scope of the invention

as defined in the following claims.