US4794890A — Electromagnetic valve actuator

Claim 1

Independent Claim 122 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated valve stem; motive means for causing the valve to move in the direction of stem elongation between valve-open and valve-closed positions; means for decelerating the valve as the valve nears one of said valve-open and valve-closed positions including at least two separate damping arrangements jointly effective to slow valve motion as the valve gets close to said one position; a latching arrangement for maintaining the valve in one of said valve-open and valve-closed positions; the motive means including an electromagnetic repulsion arrangement operable when energized to override the latching arrangement and dislodge the valve from the position in which the valve was maintained.

Claim 2

Dependent Claim 122 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated valve stem; motive means for causing the valve to move in the direction of stem elongation between valve-open and valve-closed positions; means for decelerating the valve as the valve nears one of said valve-open and valve-closed positions including at least two separate damping arrangements jointly effective to slow valve motion as the valve gets close to said one position; a latching arrangement for maintaining the valve in one of said valve-open and valve-closed positions; the motive means including an electromagnetic repulsion arrangement operable when energized to override the latching arrangement and dislodge the valve from the position in which the valve was maintained.

Claim 3

Dependent Claim 55 words

The electronically controllable valve mechanism of claim 1 wherein the electromagnetic repulsion arrangement includes a relatively fixed annular coil, an annular conductor movable with the valve stem and juxtaposed with the coil when the valve is in one of said valve-open and valve-closed positions, and electrical circuitry for providing a sudden current through the coil.

Claim 4

Dependent Claim 21 words

The electronically controllable valve mechanism of claim 2 wherein the electrical circuitry includes a pair of individually enableable field effect transistors.

Claim 5

Dependent Claim 32 words

The electronically controllable valve mechanism of claim 1 further comprising a housing at least partially surrounding the valve stem and means for circulating a liquid coolant through a portion of the housing.

Claim 6

Dependent Claim 89 words

The electronically controllable valve mechanism of claim 1 further comprising a housing at least partially surrounding the valve stem: the electromagnetic repulsion arrangement comprising first and second annular coils each fixed relative to the housing and surrounding the valve stem; and first and second spaced apart annular conductors surrounding and fixed to the valve stem, the first coil and first conductor being in juxtaposition when the valve is in the valve-open position and the second coil and second conductor being juxtaposed when the valve is in the valve-closed position.

Claim 7

Dependent Claim 75 words

The electronically controllable valve mechanism of claim 5 wherein said latching arrangement includes a permanent magnet fixed to the housing intermediate the first and second conductors, and first and second ferromagnetic members fixed to and movable with the valve stem, the valve being held in the valve-closed position by magnetic attraction between the magnet and the first ferromagnetic member and in the valve-open position by magnetic attraction between the magnetic and the second ferromagnetic member.

Claim 8

Dependent Claim 77 words

The electronically controllable valve mechanism of claim 6 wherein the permanent magnet is an annular member radially magnetized and further including inner and outer ferromagnetic pole pieces defining a first small annular air gap magnetic field which is shunted by the first ferromagnetic member when the valve is in the valve-closed position and a second small annular air gap magnetic field which is shunted by the second ferromagnetic member when the valve is in the valve-open position.

Claim 9

Dependent Claim 21 words

The electronically controllable valve mechanism of claim 1 wherein one of said damping arrangements comprises an axially compressible annular spring disk.

Claim 10

Dependent Claim 36 words

The electronically controllable valve mechanism of claim 8 wherein the annular spring is strained when the valve is in the valve-closed position to compensate for relative thermal expansion of the valve stem and insure valve closure.

Claim 11

Dependent Claim 62 words

The electronically controllable valve mechanism of claim 1 further comprising a housing at least partially surrounding the valve stem, one of said damping arrangements comprising a pneumatic damping arrangement including a housing region of reduced size and a piston fixed to the valve stem which enters the region of reduced size as the valve nears one of said valve-open and valve-closed positions.

Claim 12

Dependent Claim 85 words

The electronically controllable valve mechanism of claim 10 wherein the motive means comprises first and second annular coils each fixed relative to the housing and surrounding the valve stem; and first and second spaced apart annular conductors surrounding and fixed to the valve stem, the first coil and first conductor being in juxtaposition when the valve is in the valve-open position and the second coil and second conductor being juxtaposed when the valve is in the valve-closed position, said piston comprising one of said conductors.

Claim 13

Dependent Claim 59 words

The electronically controllable valve mechanism of claim 1 wherein one of said damping arrangements comprises a hydraulic damping arrangement including a fixed fluid filled cavity and a piston movable independent of the valve stem, the piston being impacted and driven from one cavity extreme to another cavity extreme as the valve nears one of said valve-open and valve-closed positions.

Claim 14

Dependent Claim 37 words

The electronically controllable valve mechanism of claim 1 wherein the motive means comprises a pair of like electromagnetic repulsion arrangements, one of said damping arrangements comprising one of said electromagnetic repulsion arrangements electrically connected for dynamic breaking.

Claim 15

Dependent Claim 146 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated axial stem; a housing at least partially surrounding the valve stem having a hollow interior generally shaped as a surface of revolution about the axis of the valve stem; and means within the housing and surrounding the valve stem for moving the valve along the stem axis between valve-open and valve-closed positions including in order along the stem; a first annular coil fixed relative to the housing, a first conductor fixed to the valve stem, a first spring damping device, a hydraulic damping device including a fluid filled cavity fixed to the housing and a piston movable independent of the valve stem within the cavity, a second spring damping device, a second conductor fixed to the valve stem, a second annular coil fixed relative to the housing.

Claim 16

Dependent Claim 146 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated axial stem; a housing at least partially surrounding the valve stem having a hollow interior generally shaped as a surface of revolution about the axis of the valve stem; and means within the housing and surrounding the valve stem for moving the valve along the stem axis between valve-open and valve-closed positions including in order along the stem; a first annular coil fixed relative to the housing, a first conductor fixed to the valve stem, a first spring damping device, a hydraulic damping device including a fluid filled cavity fixed to the housing and a piston movable independent of the valve stem within the cavity, a second spring damping device, a second conductor fixed to the valve stem, a second annular coil fixed relative to the housing.

Claim 17

Dependent Claim 114 words

The electronically controllable valve mechanism of claim 14 further comprising a latching arrangement for maintaining the valve in one of said valve-open and valve-closed positions including a first ferromagnetic member intermediate the first conductor and the first spring damping device, a second ferromagnetic member intermediate the second conductor and the second spring damping device, and first and second small annular air gap magnetic poles intermediate the first and second ferromagnetic members and fixed relative to ±he housing, the first poles being shunted by the first ferromagnetic member when the valve is in the valve-closed position and the second poles being shunted by the second ferromagnetic member when the valve is in the valve-open position.

Claim 18

Dependent Claim 143 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated valve stem; a housing at least partially surrounding the valve stem; means for circulating a liquid coolant through a portion of the housing; motive means for causing the valve to move in the direction of stem elongation between valve-open and valve-closed positions; means for decelerating the valve as the valve nears one of said valve-open and valve-closed positions including at least two separate damping arrangements jointly effective to slow valve motion as the valve gets close to said one position; a latching arrangement for maintaining the valve in one of said valve-open and valve-closed positions; the motive means comprising an electromagnetic repulsion arrangement operable when energized to override the latching arrangement and dislodge the valve from the position in which the valve was maintained.

Claim 19

Dependent Claim 143 words

An electronically controllable valve mechanism for use in an internal combustion engine comprising: an engine valve having an elongated valve stem; a housing at least partially surrounding the valve stem; means for circulating a liquid coolant through a portion of the housing; motive means for causing the valve to move in the direction of stem elongation between valve-open and valve-closed positions; means for decelerating the valve as the valve nears one of said valve-open and valve-closed positions including at least two separate damping arrangements jointly effective to slow valve motion as the valve gets close to said one position; a latching arrangement for maintaining the valve in one of said valve-open and valve-closed positions; the motive means comprising an electromagnetic repulsion arrangement operable when energized to override the latching arrangement and dislodge the valve from the position in which the valve was maintained.

Claim 20

Dependent Claim 55 words

The electronically controllable valve mechanism of claim 16 wherein the electromagnetic repulsion arrangement includes a relatively fixed annular coil, an annular conductor movable with the valve stem and juxtaposed with the coil when the valve is in one of said valve-open and valve-closed positions, and electrical circuitry for providing a sudden current through the coil.

Claim 21

Dependent Claim 21 words

The electronically controllable valve mechansim of claim 17 wherein the electrical circuitry includes a pair of individually enableable field effect transistors.

Claim 22

Dependent Claim 21 words

The electronically controllable valve mechanism of claim 16 wherein one of said damping arrangements comprises an axially compressible annular spring disk.

Claim 23

Dependent Claim 36 words

The electronically controllable valve mechanism of claim 19 wherein the annular spring is strained when the valve is in the valve-closed position to compensate for relative thermal expansion of the valve stem and insure valve closure.

Claim 24

Dependent Claim 62 words

The electronically controllable valve mechanism of claim 16 further comprising a housing at least partially surrounding the valve stem, one of said damping arrangements comprising a pneumatic damping arrangement including a housing region of reduced size and a piston fixed to the valve stem which enters the region of reduced size as the valve nears one of said valve-open and valve-closed positions.

Claim 25

Dependent Claim 86 words

The electronically controllable valve mechanism of claim 21 wherein the electromagnetic repulsion arrangement comprises first and second annular coils each fixed relative to the housing and surrounding the valve stem; and first and second spaced apart annular conductors surrounding and fixed to the valve stem, the first coil and first conductor being in juxtaposition when the valve is in the valve-open position and the second coil and second conductor being juxtaposed when the valve is in the valve-closed position, said piston comprising one of said conductors.

Claim 26

Dependent Claim 59 words

The electronically controllable valve mechanism of claim 16 wherein one of said damping arrangements comprises a hydraulic damping arrangement including a fixed fluid filled cavity and a piston movable independent of the valve stem, the piston being impacted and driven from one cavity extreme to another cavity extreme as the valve nears one of said valve-open and valve-closed positions.

Claim 27

Dependent Claim 37 words

The electronically controllable valve mechanism of claim 16 wherein the motive means comprises a pair of like electromagnetic repulsion arrangements, one of said damping arrangements comprising one of said electromagnetic repulsion arrangements electrically connected for dynamic breaking.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1992-01-03	1992-07-04	1993-01-03	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1996-01-03	1996-07-04	1997-01-03	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2000-01-03	2000-07-04	2001-01-03	$7700.00	Window Closed / Lapsed

Electromagnetic valve actuator

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