Magnetic field latch assembly

• US 5,782,512 A
• Filed: 01/13/1997
• Issued: 07/21/1998
• Est. Priority Date: 01/13/1997
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Cargnoni, James P.
• Primary Examiner(s): BARRETT, SUZANNE LALE DINO
• Application Number:
  US08/781,305
• Time in Patent Office: 554 Days
• Field of Search: 292/251.5, 292/341.12, 292/DIG. 73, 292/DIG. 60
• US Class Current: 292/251.5
• CPC Class Codes: E05C 19/16 Devices holding the wing by magnetic or electromagnetic attraction E05C17/56 takes precedence
• CPC Class Codes: E05C 19/166 electromagnetic
• CPC Class Codes: Y10S 292/60 Adjustment provisions
• CPC Class Codes: Y10T 292/11 Magnetic

Abstract

A magnetic field latch assembly for an apparatus having a first element and a second element with the second element having a disengaged position and an engaged position with respect to the first element. The magnetic field latch assembly employs permanent or electromagnets for shock absorption, positioning and latching the first element and the second element. The magnetic field latch assembly includes magnets associated with the first and second elements such that as the first and second elements approach each other, the magnets initially repel each other causing a braking force to slow the relative motion of the first and second elements. When the first and second elements are in the engaged position, the magnets hold the first and second elements in position and minimize vibration and chatter.

Claims

1. A magnetic field latch assembly, comprising:

a first magnet associated with a first element;

a second magnet associated with a second element, the second element having a disengaged position and an engaged position with respect to the first element; and

adjustment means for adjusting a position of at least one of the first magnet and the second magnet, the adjustment means allowing adjustment of at least an angular position of the first magnet relative to the second magnet, wherein a force between the first and the second magnets tends to separate the first and the second elements when in the disengaged position and the force between the first and the second magnets tends to draw the first and the second elements together when in the engaged position.

2. The magnetic field latch assembly of claim 1, wherein a longitudinal axis of the second magnet is in a first plane that is parallel to a second plane containing longitudinal axes of the first and the second elements, the first plane being substantially parallel to the second plane, the first and the second magnets overlapping when the first and the second elements are in the engaged position.

3. The magnetic field latch assembly of claim 2, wherein the first and the second magnets include a plurality of magnets, each of the plurality of magnets having a pole surface that is aligned with pole surfaces of other ones of the plurality of magnets, magnet axes of the plurality of magnets being aligned in a third plane, the third plane being substantially parallel to the second plane.

4. The magnetic field latch assembly of claim 2, wherein the first and the second magnets include a plurality of magnets, each of the plurality of magnets having a pole surface that is aligned with pole surfaces of other ones of the plurality of magnets, magnet axes of the plurality of magnets being aligned in a third plane, the third plane being perpendicular to the second plane.

5. The magnetic field latch assembly according to claim 4, wherein the first and the second magnets contact each other when in the engaged position.

6. The magnetic field latch assembly according to claim 4, wherein the adjustment means further allows adjustment of a longitudinal position of the first magnet relative to the second magnet.

7. The magnetic field latch assembly according to claim 6, wherein the adjusting means includes a flexible lever.

8. The magnetic field latch assembly according to claim 5, wherein the first magnets are permanent magnets and the second magnets are electromagnets.

9. The magnetic field latch assembly according to claim 5, wherein the second magnets are permanent magnets and the first magnets are electromagnets.

10. The magnetic field latch assembly according to claim 1, wherein the first and the second magnets are at least one of iron magnets, ceramic magnets and electromagnets.

11. The magnetic field latch assembly according to claim 10, wherein the first and the second magnets are electromagnets and magnetic poles of the electromagnets are activated to apply a braking force between the first and the second elements when the first and the second elements are in the disengaged position, and the magnetic poles of the electromagnets and are reversed, applying an attracting force between the first and the second elements when the first and the second elements are in the engaged position to latch the first and the second elements.

12. The magnetic field latch assembly of claim 1, wherein the first and second magnets repel each other in a first direction when the first and the second elements are in the disengaged position and repel each other in a second direction when the first and the second elements are in the engaged position, the first and second directions being different.

13. The magnetic field latch assembly of claim 12, wherein the first magnets include a first number of magnets and the second magnets include a second number of magnets.

14. The magnetic field latch assembly of claim 13, wherein the first number of magnets is two and the second number of magnets is three, the three magnets arranged so that magnetic poles of a center magnet of the second number of magnets are of opposite polarity to magnetic poles of each of an outer magnet of the second number of magnets.

15. The magnetic field latch assembly of claim 1, further comprising:

shields that enclose the first and the second magnets.

16. The magnetic latch assembly according to claim 4, wherein the first and the second magnets contact each other beginning immediately before the engaged position, so as to provide a frictional force for slowing a motion of the first element toward the second element.

17. A magnetic field latch assembly, comprising:

at least a first magnet associated with a first element;

at least a second magnet associated with a second element, the second element having a disengaged position and an engaged position with respect to the first element; and

a lever coupled to the second magnet, the lever allowing adjustment of at least an angular position of the second magnet relative to the first magnet, wherein the first and the second magnets repel each other in a first direction when the first and the second elements are in the disengaged position and the first and the second magnets repel each other in a second direction when the first and the second elements are in the engaged position, the first and the second directions being different.

18. The magnetic field latch assembly according to claim 17, wherein the lever further allows adjustment of a longitudinal position of the second magnets.

19. The magnetic latch assembly according to claim 18, wherein the first and the second magnets contact each other beginning immediately before the engaged position so as to provide a frictional force for slowing a motion of the first element toward the second element.