ELECTROMAGNETIC CLAMPING DEVICE

• US 20100071192A1
• Filed: 11/03/2008
• Published: 03/25/2010
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Menon, Manas Chandran, Sarh, Branko, Asada, Harry
• Granted Patent: US 8,490,955 B2
• Time in Patent Office: Days
• US Class Current: 29/525.60
• CPC Class Codes: B21J 15/14 specially adapted for riveting specific articles, e.g. brake lining machines
• CPC Class Codes: B21J 15/142 Aerospace structures
• CPC Class Codes: B21J 15/28 Control devices specially adapted to riveting machines not restricted to one of the preceding subgroups
• CPC Class Codes: B21J 15/42 Special clamping devices for workpieces to be riveted together, e.g. operating through the rivet holes
• CPC Class Codes: B23B 2270/08 Clamping mechanisms; Provisions for clamping B23B2210/00 takes precedence
• CPC Class Codes: B23B 35/00 Methods for boring or drilling, or for working essentially requiring the use of boring or drilling machines; Use of auxiliary equipment in connection with such methods
• CPC Class Codes: B23Q 3/1543 using electromagnets
• CPC Class Codes: B23Q 3/1546 using permanent magnets
• CPC Class Codes: B25B 11/002 Magnetic work holders
• CPC Class Codes: Y10T 279/23 with magnetic or electrostatic means
• CPC Class Codes: Y10T 29/49075 including permanent magnet or core
• CPC Class Codes: Y10T 29/49622 Vehicular structural member making
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 29/49947 by applying separate fastener
• CPC Class Codes: Y10T 29/49956 Riveting
• CPC Class Codes: Y10T 29/49998 Work holding
• CPC Class Codes: Y10T 408/03 Processes

Abstract

An apparatus may comprise a permanent magnet unit, an end effector, and an electromagnetic clamping device. The end effector may be capable of performing workpiece operations. The electromagnetic clamping device may have an activated state and a deactivated state.

Claims

1. An apparatus comprising:

a permanent magnet unit;

an end effector capable of performing workpiece operations; and

an electromagnetic clamping device having an activated state and a deactivated state.

2. The apparatus of claim 1, wherein the electromagnetic clamping device generates a magnetic field in the activated state at a strength causing the permanent magnet unit to clamp a workpiece to the electromagnetic clamping device.

3. The apparatus of claim 2, wherein the electromagnetic clamping device changes the strength of the magnetic field in the deactivated state to a level causing the permanent magnet unit to become moveable along a surface of the workpiece.

4. The apparatus of claim 1, wherein the end effector comprises at least one of a drill and a riveter.

5. The apparatus of claim 1, wherein the permanent magnet unit comprises:

a housing;

a number of permanent magnets; and

a number of low friction surfaces.

6. The apparatus of claim 5, wherein the number of low friction surfaces comprises a number of wheels.

7. The apparatus of claim 6, wherein when the electromagnetic clamping device in the deactivated state, the permanent magnet unit is in a rolling mode in which the number of wheels engage a surface of a workpiece and the number of permanent magnets moves away from the surface of the workpiece.

8. The apparatus of claim 7, wherein when the electromagnetic clamping device in the deactivated state the permanent magnet unit generates a magnetic field such that movement of the electromagnetic clamping device pulls the permanent magnet unit.

9. The apparatus of claim 6, wherein when the electromagnetic clamping device is in the activated state, the permanent magnetic unit is in a fixed mode in which the number of wheels is disengaged from a surface of a workpiece and the number of permanent magnets moves to engage the surface of the workpiece.

10. The apparatus of claim 1, wherein the electromagnetic clamping device comprises:

a first coil system capable of generating a first magnetic field causing a number of normal forces on the permanent magnet unit and the electromagnetic clamping device; and

a second coil system capable of generating a second magnetic field causing a side force on the permanent magnet unit.

11. The apparatus of claim 10, wherein the electromagnetic clamping device further comprises:

a third coil system capable of generating a third magnetic field causing a rotational force on the permanent magnet unit.

12. The apparatus of claim 1, wherein the electromagnetic clamping device comprises:

a coil system capable of generating a number of magnetic fields; and

a core, capable of providing access to a surface of a workpiece to perform work operations.

13. The apparatus of claim 12, wherein the core is capable of concentrating a force from the number of magnetic fields on a surface of the core contacting the surface of the workpiece.

14. The apparatus of claim 2, wherein the workpiece comprises a plurality of components.

15. An electromagnetic clamping system for clamping a workpiece having a plurality of components, the electromagnetic clamping system comprises:

a permanent magnet unit comprising;

a housing;

a number of permanent magnets;

a number of low friction surfaces comprising a number of wheels;

an end effector capable of performing workpiece operations, wherein the end effector comprises at least one of a drill and a riveter;

an electromagnetic clamping device having an activated state and a deactivated state, wherein the electromagnetic clamping device comprises;

a first coil system capable of generating a first magnetic field causing a number of normal forces on the permanent magnet unit and the electromagnetic clamping device;

a second coil system capable of generating a second magnetic field causing a side force on the permanent magnet unit;

a third coil system capable of generating a third magnetic field causing a rotational force on the permanent magnet unit;

a core, capable of providing access to a surface of the workpiece to perform the operations on the workpiece, wherein the core is capable of concentrating a force from a number of magnetic fields on a surface of the core contacting the surface of the workpiece; and

wherein the electromagnetic clamping device generates the number of magnetic fields in the activated state at a strength causing the permanent magnet unit to clamp the workpiece to the electromagnetic clamping device;

wherein the electromagnetic clamping device changes the strength of the number of magnetic fields in the deactivated state to a level causing the permanent magnet unit to become moveable along the surface of the workpiece;

wherein when the electromagnetic clamping device is in the deactivated state, the permanent magnet unit is in a rolling mode in which the number of wheels engages the surface of the workpiece and the number of permanent magnets moves away from the surface of the workpiece;

wherein when the electromagnetic clamping device is in the deactivated state, the permanent magnet unit generates a magnetic field such that movement of the electromagnetic clamping device pulls the permanent magnet unit;

wherein when the electromagnetic clamping device is in the activated state, the permanent magnetic unit is in a fixed mode in which the number of wheels is disengaged from the surface of the workpiece and the number of permanent magnets moves to engage the surface of the workpiece.

16. A method for performing an operation on a workpiece, the method comprising:

positioning a permanent magnet unit on a first surface of the workpiece;

positioning an electromagnetic clamping device on a second surface of the workpiece, wherein the first surface opposes the second surface;

placing the electromagnetic clamping device in an activated state such that a number of forces caused by magnetic field clamps the workpiece between the electromagnetic clamping device and the permanent magnet unit; and

performing an operation on the workpiece.

17. The method of claim 16 further comprising:

placing the electromagnetic clamping device in a deactivated state after performing the operation such that the electromagnetic clamping device changes the magnetic field to change a strength of the number of clamping forces allowing the permanent magnet unit to become moveable on the first surface; and

moving the permanent magnet unit with the electromagnetic clamping device.

18. The method of claim 17, wherein the moving step comprises:

moving the electromagnetic clamping device, wherein the electromagnetic clamping device pulls the permanent magnet unit.

19. The method of claim 17, wherein the moving step comprises:

generating another magnetic field to cause a side force to move the permanent magnetic unit on the first surface.

20. The method of claim 16, wherein the workpiece comprises two components.

21. The method of claim 16, wherein the operation is selected from at least one of a drilling operation and a fastening operation.

22. A method for performing an operation on a workpiece having at least two components with an electromagnetic clamping system, the method comprising:

positioning a permanent magnet unit in the electromagnetic clamping system on a first surface of the workpiece;

positioning an electromagnetic clamping device in the electromagnetic clamping system on a second surface of the workpiece, wherein the first surface opposes the second surface;

placing the electromagnetic clamping device in an activated state such that a number of forces caused by a magnetic field clamps the workpiece between the electromagnetic clamping device and the permanent magnet unit;

performing the operation on the workpiece, wherein the operation is selected from at least one of a drilling operation and a fastening operation;

placing the electromagnetic clamping device in a deactivated state after performing the operation such that the electromagnetic clamping device changes the magnetic field to a strength of the number of forces allowing the permanent magnet unit to become moveable on the first surface; and

moving the permanent magnet unit with the electromagnetic clamping device by at least one of moving the electromagnetic clamping device, wherein the electromagnetic clamping device pulls the permanent magnet unit, and generating another magnetic field causing a side force to move the permanent magnetic unit on the first surface.

23. A method for assembling parts, the method comprising:

placing a sealant between a plurality of parts in a stack up to form a workpiece;

clamping the workpiece using a permanent magnet unit and an electromagnetic clamping device in an activated state such that a number of forces caused by a magnetic field clamps the workpiece between the electromagnetic clamping device and the permanent magnet unit;

drilling a number of holes in the work piece; and

installing a number of fasteners in the number of holes.