Valve assembly having electrical actuator with balanced stator

Patent metadata

Field	Value
Publication number	US-11459987-B2
Application number	US-202016992487-A
Country	US
Kind code	B2
Filing date	Aug 13, 2020
Priority date	Aug 13, 2020
Publication date	Oct 4, 2022
Grant date	Oct 4, 2022

Abstract

A valve assembly for a pump includes an electrical actuator having a stator and an armature. The stator includes an annular outer stator portion and an annular inner stator portion, and an annular channel formed radially between the outer stator portion and the inner stator portion. A first radial channel extending through the annular outer stator portion between an outer surface of the outer stator portion and the annular channel, and at least one second opening in the annular outer stator portion results in magnetic symmetry of the stator. Upon activating the electrical actuator, the attraction of the armature towards the stator is uniform thus displacing fluid between the stator and armature in a uniform manner and to avoid high velocity, potentially damaging fluid flow.

First claim

What is claimed is:

1. A valve assembly comprising:
a valve member operatively associated with a valve seat, the valve member being movable along a central axis between a first open position at which the valve member is spaced from the valve seat and a second closed position at which the valve member engages the valve seat to seal an opening of the valve assembly;
an electrical actuator including a stator, and an armature coupled to the valve member;
the stator includes an annular outer stator portion and an annular inner stator portion, and an annular channel formed radially between the outer stator portion and the inner stator portion, a first radial channel extending through the annular outer stator portion between an outer surface of the outer stator portion and the annular channel, and at least one second opening disposed in the annular outer stator portion on an opposite half of the stator from the first radial channel, the stator being magnetically symmetrical along a line bisecting the first radial channel and perpendicular to the central axis;
a winding and terminal assembly, the winding and terminal assembly comprises an electrically conductive winding disposed within the annular channel and between the outer stator portion and the inner stator portion and electrically conductive terminals electrically connected to the winding, a portion of the winding and terminal assembly extending through the first radial channel; and
the armature including an armature plate defining an armature center axis, the armature center axis being co-linear with the central axis and being movable between a rest position and an activated position to vary a position of the valve member, in response to a change to an energy state of the electrical actuator, the armature plate including a top armature surface facing the stator.

2. The valve assembly of claim 1 , wherein the at least one second opening comprises a second radial channel extending through the annular outer stator portion between the outer surface of the outer stator portion and the annular channel, the second radial channel being diametrically opposite the first radial channel.

3. The valve assembly of claim 1 , further including an insulative over-molding encasing the winding and disposed in the annular channel.

4. The valve assembly of claim 1 , wherein the outer stator portion includes an outer stator end face and the inner stator portion includes an inner stator end face, and the outer stator end face and the inner stator end face lie in a common plane.

5. The valve assembly of claim 1 , wherein the winding and terminal assembly further includes a bobbin assembly around which the windings are wrapped.

6. The valve assembly of claim 1 , wherein the at least one second opening comprises a second radial channel extending through the annular outer stator portion between the outer surface of the outer stator portion and the annular channel, the second radial channel being aligned with the first radial channel and on opposite sides of the central axis.

7. The valve assembly of claim 1 , wherein the stator has an upper surface and a lower surface, the lower surface being disposed closer to the armature plate than the upper surface, and the lower surface of the stator is diametrically symmetrical.

8. The valve assembly of claim 1 , wherein the stator has an upper surface and a lower surface, the lower surface being disposed closer to the armature plate than the upper surface, and the lower surface is symmetrical about a bisecting line through the first radial channel and intersecting with and perpendicular to the central axis.

9. The valve assembly of claim 8 , wherein the outer surface of the outer stator portion is symmetrical about the bisecting line.

10. The valve assembly of claim 8 , wherein the stator is symmetrical about the bisecting line.

11. The valve assembly of claim 1 , further comprising an over-molded body that extends about the stator and into each of the first and second radial channels.

12. A valve assembly comprising:
a valve member operatively associated with a valve seat, the valve member being movable along a central axis between a first open position at which the valve member is spaced from the valve seat and a second closed position at which the valve member engages the valve seat to seal an opening of the valve assembly;
an electrical actuator including a stator, and an armature coupled to the valve member;
the stator includes an annular outer stator portion and an annular inner stator portion, and an annular channel formed radially between the outer stator portion and the inner stator portion, a first radial channel extending through the annular outer stator portion between an outer surface of the outer stator portion and the annular channel, and at least one second opening disposed in the annular outer stator portion on an opposite half of the stator from the first radial channel, the stator being magnetically symmetrical along a line bisecting the first radial channel and perpendicular to the central axis;
a winding and terminal assembly, the winding and terminal assembly comprises an electrically conductive winding disposed within the annular channel and between the outer stator portion and the inner stator portion and electrically conductive terminals electrically connected to the winding, a portion of the winding and terminal assembly extending through the first radial channel;
an over-molded body that extends about the stator and into each of the first radial channel and the at least one second opening; and
the armature including an armature plate defining an armature center axis, the armature center axis being co-linear with the central axis and being movable between a rest position and an activated position to vary a position of the valve member, in response to a change to an energy state of the electrical actuator, the armature plate including a top armature surface facing the stator.

13. The valve assembly of claim 1 , further including an insulative over-molding encasing the winding and disposed in the annular channel.

14. The valve assembly of claim 12 , wherein the stator has an upper surface and a lower surface, the lower surface being disposed closer to the armature plate than the upper surface, and the lower surface of the stator is diametrically symmetrical.

15. The valve assembly of claim 12 , wherein the stator has an upper surface and a lower surface, the lower surface being disposed closer to the armature plate than the upper surface, and the lower surface is symmetrical about a bisecting line through the first and second radial channels and intersecting with the central axis.

16. The valve assembly of claim 15 , wherein the outer surface of the outer stator portion is symmetrical about the bisecting line.

17. The valve assembly of claim 15 , wherein the stator is symmetrical about the bisecting line.

18. The valve assembly of claim 1 , further comprising an over-molded body that extends about the stator and into each of the first and second radial channels.

19. A pump comprising:
a pump housing;
a pumping element movable between a retracted position and an advanced position within a pumping chamber formed in the pump housing;
a valve assembly for controlling a flow of a fluid to or from the pumping chamber, the valve assembly including
a valve member operatively associated with a valve seat, the valve member being movable along a central axis between a first open position at which the valve member is spaced from the valve seat and a second clos

Assignees

• Caterpillar Inc

Inventors

• Nelson Bryan E
• Arya Nikhil M
• Menssen Andrew J

Classifications

• H01F7/081

  Magnetic constructions · CPC title

• F02M2200/04

  Fuel-injection apparatus having means for avoiding effect of cavitation, e.g. erosion · CPC title

• H02K1/12

  Stationary parts of the magnetic circuit · CPC title

• F02M59/466 Primary

  Electrically operated valves, e.g. using electromagnetic or piezoelectric operating means · CPC title

• H02K16/00

  Machines with more than one rotor or stator {(machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029)} · CPC title