Rollable Magnetic Clamp
A magnetic clamping device which uses rollers or wheels to create an air-gap between the clamping edges and a ferromagnetic work-piece, thereby reducing friction so that the clamp is able to be rolled or easily moved upon the surface or surfaces to which it is clamped.
The present Utility Patent Application claims priority benefit of the U.S. Provisional Application for patent No. 60/706,726 filed on Aug. 10, 2005 under 35 U.S.C 119(e)
FIELD OF THE INVENTIONThe invention pertains to permanent magnetic clamping devices and specifically to permanent magnetic clamping devices used to clamp ferromagnetic workpieces together during fusion of said workpieces such as by welding or other joining processes.
BACKGROUND OF THE INVENTIONThe clamping together of ferromagnetic workpieces with magnetic clamping devices during welding or similar processes is made awkward by the limited manoueverability of such clamping devices once they are magnetically clamped to such workpieces.
This limitation in manoueverability makes it difficult to adjust a workpiece to a pre-determined position or mark once the magnetic clamping device has gripped the surface of either of the ferromagnetic workpieces. It is common to use hammers or other implements to effect such adjustment, with the consequent risk of damage to either the workpieces or the magnetic clamping device.
Furthermore, such clamping devices often require relatively excessive force to remove from the workpieces after use.
In view of the foregoing, there is a need for a magnetic clamping device that can more easily be manouevered once in position on a workpiece or workpieces.
DETAILED DESCRIPTION OF THE INVENTIONThe present invention is illustrated by way of example, and not by way of limitation in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
To achieve the foregoing and other objectives of the purpose of the invention a typical embodiment is described. In one embodiment rotatable rollers or wheels of preferably non-magnetic material which could be plastic or non-magnetic metal such as brass or aluminum are of such diameter and so disposed on the magnetic clamping device as to provide a small air-gap between the clamping edges of the pole plates and the surface on which the clamping device is placed, such that there is no frictional contact between the edges of the pole plates and the clamped surface. This small air-gap, provided by the rollers or wheels ensures that magnetic clamping is still effected but also that the clamping device may be manually propelled along the ferromagnetic surface to which it is magnetically clamped. In a typical embodiment these rollers or wheels have their axle through the pole plates of the clamping device. The rollers or wheels may be near the corners or disposed at any points around the perimeter of the clamping device. In an alternative embodiment the rollers or wheels may be disposed on the outside of the pole plates. In a further alternative embodiment the rollers or wheels may be of ferromagnetic material and disposed within or outside the pole plates in such a manner that they do or do not not provide a shunt to the magnetic field between the pole plates. Further alternative embodiments may include rollers or wheels that are not rotatable or a combination of rotatable and non-rotatable elements to provide the necessary air-gap.
The embodiments disclosed are not intended to limit the invention to those forms. The invention is thus to cover all modifications, equivalents and alternatives falling within the spirit and scope of the following claims.
Claims
1. A magnetic clamping device of the type having two or more ferromagnetic pole plates with a magnetizing element between them, having rollers or wheels of preferably non-magnetic material such as aluminium or brass or plastic fixed rotatably between the pole plates at several points around the perimeter of the device and of such diameter and location that the perimeter of the rollers always provides a small air-gap between the edges of the pole plates and any surface upon which the clamp is placed for the purpose of clamping.
2. A magnetic clamping device of the type having two or more ferromagnetic pole plates with a magnetizing element between them, having rollers or wheels of preferably non-magnetic material such as aluminium or brass or plastic fixed rotatably on the outer side of the pole plates at sveral points around the perimeter of the device and of such diameter and location that the perimeter of the rollers always provides a small air-gap between the edges of the pole plates and any surface upon which the clamp is placed for the purpose of clamping.
3. A magnetic clamping device of the type having two or more ferromagnetic pole plates with a magnetizing element between them, having rollers or wheels of ferromagnetic material fixed rotatably either between or on the outer side of the pole plates at several points around the perimeter of the device and of such diameter and location that the perimeter of the rollers always provides a small air-gap between the edges of the pole plates and any surface upon which the clamp is placed for the purpose of clamping.
4. A magnetic clamping device of the type having two or more ferromagnetic pole plates with a magnetizing element between them, having non-rotatable elements fixed as for any of the above claims so as to provide a small air-gap between the edges of the pole plates and any surface upon which the clamp is placed and to provide decreased friction between the clamp and the surface upon which it is clamped.
5. A magnetic clamp as described in claims 1 to 4 where the element to provide an air-gap between the clamping edges of the clamp and the surface to which it clamps is a magnetic or non-magnetic and non-rotatable skid or protrusion.
6. A magnetic clamp as decribed in claims 1 to 3 where the rotating rollers or wheels are of a type that enables movement in more than one direction.
Type: Application
Filed: Aug 4, 2006
Publication Date: Feb 15, 2007
Inventor: Ian Heard (Elanora Heights)
Application Number: 11/462,365
International Classification: A47G 1/17 (20060101);