Residual magnetic devices and methods

• US 8,403,124 B2
• Filed: 03/30/2005
• Issued: 03/26/2013
• Est. Priority Date: 03/30/2005
• Status: Active Grant

• Current Assignee: Strattec Security Corporation
• Original Assignee: Strattec Security Corporation
• Inventors: Dimig, Steven J., Organek, Gregory J., Feucht, Michael G.
• Primary Examiner(s): BONCK, RODNEY H
• Application Number:
  US11/094,801
• Publication Number:
  US 20060225985A1
• Time in Patent Office: 2,918 Days
• Field of Search: 192/84.5, 192/84.92
• US Class Current: 192/84.9
• CPC Class Codes: B60N 2/919 Positioning and locking mechanisms B60N2/16, B60N2/18, B60N2/22, B60N2/225 take precedence
• CPC Class Codes: B60R 25/021 restraining movement of the steering column or steering wheel hub, e.g. restraining means controlled by ignition switch
• CPC Class Codes: B60R 25/02147 comprising a locking member having other than linear, axial or radial motion, e.g. rotatable; Steering column locking using balls, rollers or the like
• CPC Class Codes: B60R 25/08 operating on brakes or brake systems
• CPC Class Codes: E05B 47/0004 said core being linearly movable
• CPC Class Codes: E05B 47/0005 said core being rotary movable
• CPC Class Codes: E05B 47/0006 having a non-movable core; with permanent magnet
• CPC Class Codes: E05B 53/008 by planetary gears
• CPC Class Codes: E05B 81/00 Power-actuated vehicle locks
• CPC Class Codes: E05B 81/08 using electromagnets or solenoids
• CPC Class Codes: E05B 81/14 operating on bolt detents, e.g. for unlatching the bolt
• CPC Class Codes: E05C 17/003 Power-actuated devices for limiting the opening of vehicle doors
• CPC Class Codes: E05C 19/166 electromagnetic
• CPC Class Codes: F16D 27/004 with permanent magnets combined with electromagnets
• CPC Class Codes: F16D 27/06 with friction surfaces arranged within the flux
• CPC Class Codes: F16D 27/112 with flat friction surfaces, e.g. discs
• CPC Class Codes: H01F 13/00 Apparatus or processes for magnetising or demagnetising devices for holding workpieces using magnetic or electric force acting directly on the workpieces B23Q3/15 ; for degaussing ships B63G9/06; for clocks or watches G04D9/00; recording or erasing of information on magnetic record carriers G11B5/00 ; demagnetising arrangements for colour television H04N9/29
• CPC Class Codes: H01F 13/006 Methods and devices for demagnetising of magnetic bodies, e.g. workpieces, sheet material for erasing of information on magnetic record carriers G11B5/00
• CPC Class Codes: H01F 7/04 Means for releasing the attractive force
• CPC Class Codes: H01F 7/121 Guiding or setting position of armatures, e.g. retaining armatures in their end position
• CPC Class Codes: H01F 7/13 : characterised by pulling-force characteristics
• CPC Class Codes: H01F 7/18 : Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
• CPC Class Codes: H02K 33/02 : with armatures moved one way by energisation of a single coil system and returned by mechanical force, e.g. by springs
• CPC Class Codes: Y10T 70/7062 : Electrical type [e.g., solenoid]

Abstract

Residual magnetic locks, brakes, rotation inhibitors, clutches, actuators, and latches. The residual magnetic devices can include a core housing and an armature. The residual magnetic devices can include a coil that receives a magnetization current to create an irreversible residual magnetic force between the core housing and the armature.

Claims

1. A clutch for use in coupling a first element to a second element, the clutch comprising:

a core housing coupled to one of the first element and the second element;

an armature positioned adjacent to the core housing, the armature coupled to one of the first element and the second element; and

a coil positioned in the core housing, the coil receiving a magnetization current to create a substantially closed magnetic path including an air gap from approximately 0.002 inches to approximately 0.005 inches between the core housing and the armature in order to create an irreversible residual magnetic force with a magnetic air gap energy of at least 6652 (line-amp-turn)/cm³ and to couple the first element to the second element in the subsequent absence of the magnetization current and in the absence of any other magnetic force.

2. The clutch of claim 1 further comprising a controller to provide the coil with the magnetization current to create the irreversible residual magnetic force between the armature and the core housing.

3. The clutch of claim 1 wherein magnetic domains become misaligned in at least one of the armature and the core housing in order to null the irreversible residual magnetic force by at least one of a controller providing a demagnetization current to the coil and a release mechanism increasing an air gap between the armature and the core housing.

4. The clutch of claim 3 wherein the controller restores the irreversible residual magnetic force by providing the magnetization current again to the coil.

5. The clutch of claim 1 wherein the irreversible residual magnetic force substantially prevents a shear force from causing movement between the armature and the core housing.

6. The clutch of claim 1 wherein the irreversible residual magnetic force allows rotational movement of the first element.

7. The clutch of claim 6 wherein the irreversible residual magnetic force allows translational movement of the first element.

8. The clutch of claim 1 wherein the irreversible residual magnetic force allows translational movement of the first element.

9. The clutch of claim 1 wherein a first cross-sectional area of an inner core of the core housing is substantially equal to a second cross-sectional area of an outer core of the core housing, which is substantially equal to a third cross-sectional area of the armature, which is substantially equal to a fourth cross-sectional area of a yoke of the core housing.

10. The clutch of claim 1 wherein at least one of the armature and the core housing are constructed of at least one of SAE 1002 steel, SAE 1018 steel, SAE 1044 steel, SAE 1060 steel, SAE 1075 steel, and SAE 52100 steel.

11. The clutch of claim 1 wherein at least one of the armature and the core housing are constructed of chromium steel.

12. The clutch of claim 1 wherein a controller determines whether the irreversible residual magnetic force is present between the core housing and the armature.

13. The clutch of claim 1 wherein substantially all portions of the core housing and the armature magnetically saturate at substantially the same time.

14. The clutch of claim 1 wherein a demagnetization current is a substantially constant value due to the core housing and the armature being magnetically saturated when the irreversible residual magnetic force is created.

15. A clutch for use in coupling a first element to a second element, the clutch comprising:

electromagnetic assembly means coupled to the first element and the second element; and

controller means for providing a magnetization current to the electromagnetic assembly means to create a substantially closed magnetic path including an air gap from approximately 0.002 inches to approximately 0.005 inches in order to create an irreversible residual magnetic force with a magnetic air gap energy of at least 6652 (line-amp-turn)/cm³ and to couple the first element to the second element in a subsequent absence of the magnetization current and in the absence of any other magnetic force.

16. The clutch of claim 15 wherein the controller means provides a demagnetization current to the electromagnetic assembly means to null the irreversible residual magnetic force in order to allow the first element to move with respect to the second element.

17. The clutch of claim 15 and further comprising separation means for physically increasing an air gap between the armature and the core housing and substantially nulling the irreversible residual magnetic force.

18. The clutch of claim 15 and further comprising means for misaligning magnetic domains in the electromagnetic assembly means in order to null the irreversible residual magnetic force.

19. The brake of claim 18 wherein the controller means restores the irreversible residual magnetic force in the electromagnetic assembly means by providing the magnetization current again.