Constant current vacuum regulator

Claim 2

An electromagnetic solenoid valve assembly comprising: a valve housing defining a fluid chamber; a fluid passageway communicating with said fluid chamber; a magnetic pole piece having a top and a bottom end; a seat member extending beyond the bottom end of said pole piece; a magnetic closure member located a predetermined distance from the bottom end of said pole piece and adapted to control the flow of fluid through said fluid passageway, said predeteremined distance between said magnetic closure member and the bottom end of said pole piece defining a primary air gap in the magnetic flux path of the solenoid; first flux collector means for completing the magnetic flux path from the top end of said pole piece to said magnetic closure member, said first flux collector means defining a secondary air gap in said magnetic flux path at the top end of said pole piece between said pole piece and said first flux collector means and hence a first flux path across said secondary air gap; adjustable flux collector means defining a supplemental flux path across aid secondary air gap in parallel with said first flux path; means for establishing the flow of electromagnetic flux through said flux paths; and calibration means for varying the position of said adjustable flux collector means relative to said first flux collector means to vary the reluctance in said supplemental flux path.

Claim 3

The solenoid valve assembly of claim 1 wherein said first flux collector means includes an upper magnetic segment that surrounds the top end of said pole piece.

Claim 4

The solenoid valve assembly of claim 2 wherein said solenoid has associated therewith an axis aligned with said pole piece and further wherein said upper magnetic segment is annular shaped and the secondary air gap is defined by the radial distance between said upper magnetic segment and said pole piece.

Claim 5

The solenoid valve assembly of claim 3 wherein said adjustable flux collector means comprises a magnetic member located adjacent to the top end of said pole piece and to said upper magnetic segment.

Claim 6

The solenoid valve assembly of claim 4 wherein said calibration means is adapted to vary the axial position of said adjustable flux collector means relative to said upper magnetic segment.

Claim 7

The solenoid valve assembly of claim 5 wherein said calibration means comprises a nonmagnetic screw that is fixedly connected to said adjustable flux collector means and threadedly engaged to the top of said pole piece.

Claim 8

The second valve assembly of claim 5 wherein said adjustable flux collector means comprises a substantially disc-shaped magnetic member that overlays the top end of said pole piece and at least a part of said annular-shaped upper magnetic segment.

Claim 9

The solenoid valve assembly of claim 5 wherein the calibrated position of said adjustable flux collector means is secured with a light-cured polymer adhesive

Claim 10

A proportional solenoid valve assembly adapted to be connected into a fluid circuit for controlling the pressure in said fluid circuit in accordance with an electrical signal provided to the solenoid, including: a valve housing defining a fluid chamber adapted to be connected to said fluid circuit for communication therewith; a magnetic pole piece having a top end and a bottom end and defining a fluid passageway having an inlet port adjacent said top end and an exit port adjacent said bottom end in communication with said fluid chamber; a nonmagnetic seat member extending beyond the bottom end of said pole piece; a flat disc-type magnetic armature located a predetermined distance from the bottom end of said pole piece and adapted to control the flow of fluid out of said exit port into said fluid chamber, said predetermined distance between the bottom end of said pole piece and said armature defining a primary air gap in the magnetic flux path of the solenoid; flux collector means for completing the return magnetic flux path from the top end of said pole piece to said armature including a first annular portion surrounding said armature, a second portion adjacent the top end of said pole piece and defining a secondary air gap in the magnetic flux path of the solenoid corresponding to the radial distance between said pole piece and said second portion, and a third portion connecting said first and second portions; an adjustable flux collector member spaced from and overlaying the top end of said pole piece and at least a part of said second portion for defining a supplemental flux path across said secondary air gap; means for establishing the flow of electromagnetic flux through said flux path; calibration means associated with said adjustable flux collector member for varying the position of said adjustable flux collector member relative to said pole piece and said second portion for varying the reluctance of said supplemental flux path.

Claim 11

A proportional solenoid valve assembly adapted to be connected into a fluid circuit for controlling the pressure in said fluid circuit in accordance with an electrical signal provided to the solenoid, including: a valve housing defining a fluid chamber adapted to be connected to said fluid circuit for communication therewith; a magnetic pole piece having a top end and a bottom end and defining a fluid passageway having an inlet port adjacent said top end and an exit port adjacent said bottom end in communication with said fluid chamber; a nonmagnetic seat member extending beyond the bottom end of said pole piece; a flat disc-type magnetic armature located a predetermined distance from the bottom end of said pole piece and adapted to control the flow of fluid out of said exit port into said fluid chamber, said predetermined distance between the bottom end of said pole piece and said armature defining a primary air gap in the magnetic flux path of the solenoid; flux collector means for completing the return magnetic flux path from the top end of said pole piece to said armature including a first annular portion surrounding said armature, a second portion adjacent the top end of said pole piece and defining a secondary air gap in the magnetic flux path of the solenoid corresponding to the radial distance between said pole piece and said second portion, and a third portion connecting said first and second portions; an adjustable flux collector member spaced from and overlaying the top end of said pole piece and at least a part of said second portion for defining a supplemental flux path across said secondary air gap; means for establishing the flow of electromagnetic flux through said flux path; calibration means associated with said adjustable flux collector member for varying the position of said adjustable flux collector member relative to said pole piece and said second portion for varying the reluctance of said supplemental flux path.

Claim 12

The proportional solenoid valve of claim 9 wherein said solenoid has associated therewith an axis aligned with said pole piece and wherein said calibration means is adapted to vary the axial distance between the top of said pole piece and said adjustable flux collector member.

Claim 13

The proportional solenoid valve of claim 10 wherein said calibration means is further adapted to simultaneously vary the axial distance between said second portion and said adjustable flux collector member.

Claim 14

The proportional solenoid valve of claim 11 wherein said calibration means comprises a nonmagnetic screw that is fixedly connected to said adjustable flux collector member and threadedly engaged to the top of said pole piece.

Claim 15

The proportional solenoid valve of claim 12 wherein said adjustable flux collector member comprises a substantially disc-shaped member having a central bore for receiving said calibration screw

Claim 16

The proportional solenoid valve of claim 13 wherein said second portion surrounds the top end of said pole piece and the top of said pole piece is substantially flush in the axial direction with said second portion.

Claim 17

The proportional solenoid valve of claim 13 wherein the calibrated position of said adjustable flux collector member is secured with a curable material that is applied in a flowable state.

Claim 18

In an electromagnetic solenoid valve assembly comprising a plurality of magnetic segments defining a flux path including a pole piece, an armature spaced from one end of the pole piece so as to define a primary air gap therebetween, and flux collector means for completing the return magnetic flux path from said armature to the other end of said pole piece including an upper magnetic segment located adjacent to the other end of said pole piece, and means for establishing the flow of electromagnetic flux through said flux path; the improvement comprising: a secondary air gap in said magnetic flux path at the other end of said pole piece between said upper magnetic segment and said pole piece; a first flux path across said secondary air gap from said pole piece to said upper magnetic segment; and an adjustable magnetic segment located adjacent to the other end of said pole piece and adjacent to said upper magnetic segment for creating a supplemental flux path across said secondary air gap in parallel with said first flux path from said pole piece through said adjustable magnetic segment to said upper magnetic segment; the position of said adjustable magnetic segment relative to said upper magnetic segment being adjustable to vary the reluctance in said supplemental flux path.

Claim 19

In an electromagnetic solenoid valve assembly comprising a plurality of magnetic segments defining a flux path including a pole piece, an armature spaced from one end of the pole piece so as to define a primary air gap therebetween, and flux collector means for completing the return magnetic flux path from said armature to the other end of said pole piece including an upper magnetic segment located adjacent to the other end of said pole piece, and means for establishing the flow of electromagnetic flux through said flux path; the improvement comprising: a secondary air gap in said magnetic flux path at the other end of said pole piece between said upper magnetic segment and said pole piece; a first flux path across said secondary air gap from said pole piece to said upper magnetic segment; and an adjustable magnetic segment located adjacent to the other end of said pole piece and adjacent to said upper magnetic segment for creating a supplemental flux path across said secondary air gap in parallel with said first flux path from said pole piece through said adjustable magnetic segment to said upper magnetic segment; the position of said adjustable magnetic segment relative to said upper magnetic segment being adjustable to vary the reluctance in said supplemental flux path.

Claim 20

The solenoid valve assembly of claim 16 wherein said upper magnetic segment substantially surrounds the other end of said pole piece and said secondary air gap is defined by the radial distance between said upper magnetic segment and said pole piece.

Claim 21

The solenoid valve assembly of claim 17 wherein said solenoid has associated therewith an axis aligned with said pole piece and further wherein said adjustable magnetic segment is axially spaced from and overlays the other end of said pole piece and at least a part of said upper magnetic segment.

Claim 22

The solenoid valve assembly of claim 18 wherein the axial position of said adjustable magnetic segment relative to the other end of said pole piece and to said upper magnetic segment is adjustable.

Claim 23

The solenoid valve assembly of claim 19 further including a nonmagnetic screw fixedly connected to said adjustable magnetic segment and threadedly engaged to the other end of said pole piece.

Claim 24

The solenoid valve assembly of claim 16 wherein the calibrated position of said adjustable magnetic segment is secured by a curable material that is applied in a flowable state.

Claim 27

The method of claim 22 further including the step of securing the calibrated position of said adjustable magnetic segment.

Claim 28

The method of claim 23 wherein said securing step is performed by applying a light-curable polymer adhesive to said adjustable magnetic segment and thereafter exposing said polymer adhesive to light.