Enhanced permanent magnet electromagnetic actuator for an electronic valve actuation system of an engine

• US 7,249,579 B2
• Filed: 06/21/2004
• Issued: 07/31/2007
• Est. Priority Date: 03/25/2004
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Liang, Feng, Degner, Michael
• Primary Examiner(s): Denion; Thomas
• Assistant Examiner(s): Riddle; Kyle M.
• Application Number:
  US10/873,711
• Publication Number:
  US 20050211200A1
• Time in Patent Office: 1,135 Days
• Field of Search: 123/90.11, 251/129.09, 251/129.16, 335/229, 335/268, 335/304, 310/12, 310/30
• US Class Current: 123/90.11
• CPC Class Codes: F01L 2009/2136 Two opposed springs for intermediate resting position of the armature
• CPC Class Codes: F01L 2009/2148 using permanent magnet
• CPC Class Codes: F01L 9/20 by electric means
• CPC Class Codes: H02K 3/28 Layout of windings or of connections between windings windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32
• CPC Class Codes: H02K 3/34 between conductors or between conductor and core, e.g. slot insulation

Abstract

A valve actuator for an internal combustion engine is described having a core having a wound coil located therein, said core further having at least one permanent magnet located at least partially inside or outside said coil and positioned at an angle relative to a direction of movement of an armature. Further, various recesses, indentations, chamfers, bevels, and/or depressions may be included to affect flux leakage, and/or force generation.

Claims

1. A valve actuator for an internal combustion engine, comprising:

at least one electromagnet having a coil wound about a core, said core having a center pole, a first side pole and a second side pole;

an armature fixed to an armature shaft extending axially through the core, and axially movable relative thereto;

a first permanent magnet contained at least partially within a body of the first side pole, extending at least partially along the first side pole and said first permanent magnet exterior to said coil, wherein said first permanent magnet has a surface angled relative to axial movement of said shaft; and

a second permanent magnet contained at least partially within a body of the second side pole, extending at least partially along the second side pole, and said second permanent magnet exterior said coil, wherein said second permanent magnet has a surface angled relative to axial movement of said shaft;

wherein said first permanent magnet and said second permanent magnet are arranged symmetrically about an axis of said axial movement of said shaft.

2. The actuator of claim 1 further comprising a first air gap in the body of said first side pole adjacent to said first permanent magnet.

3. The actuator of claim 2 wherein said core separates said coil from said air gap.

4. The actuator of claim 1 wherein the first and the second permanent magnets are at least partially angled relative to axial movement of said shaft.

5. The actuator of claim 1 wherein the first permanent magnet has a cross-sectional shape wit a peak on an opposite side from said armature, and two ends extending toward said armature at an angle.

6. A valve actuator for an internal combustion engine, comprising:

a core having a wound coil located therein, said core further including a first permanent magnet located at least partially along a first side of said coil and a second permanent magnet located at least partially along a second side of said coil opposite said first side, wherein said first and second permanent magnets are external a region defined by said coil, are incline relative to an axis of movement of an armature and are arranged symmetrically about an axis of said movement of the armature, said core further having a recess in a surface of one of an armature end and a non-armature end of said core for increasing force when current flows in a first direction, and decreasing force when current flows in a second direction.

7. The valve actuator of claim 6 wherein said recess is located in a center pole of said core.

8. The valve actuator of claim 6 wherein said recess is located in a side pole of said core.

9. The valve actuator of claim 6 wherein said recess is angled.

10. The valve actuator of claim 6 wherein said recess is curved.

11. The valve actuator of claim 6 wherein said recess is a notch.

12. The valve actuator of claim 6 wherein said recess is located adjacent to an end of said first permanent magnet.

13. A valve actuator for an internal combustion engine, comprising:

at least one electromagnet having a coil wound about a core, said core having at least a first, second, and third section, wherein said second section is located at least partially between said first and third sections;

an armature fixed to an armature shaft extending axially through the core, and axially movable relative thereto; and

at least one permanent magnet in each of said first and third sections extending at least partially into an interior portion of the coil, wherein said at least one permanent magnet is at least partially angled relative to axial movement of said shaft; and

wherein said second section contains at least one permanent extending at least partially into said interior portion of the coil, where said permanent magnet of said second section is smaller than said permanent magnet of one of said first and third section.