摘要:
Disclosed are various embodiments for a system and method of processing a surface using a mixture containing magnetic particles. A mixture is disposed on a workpiece and exposed to a dynamic magnetic field. In response to the dynamic magnetic field, the magnetic particles of the mixture may move along the workpiece. The movement of the magnetic particles creates a pattern of grooves on the surface of the workpiece.
摘要:
A system for magnetorheological finishing of a substrate. A spherical wheel meant for carrying a magnetorheological finishing fluid houses a variable-field permanent magnet system having north and south iron pole pieces separated by primary and secondary gaps with a cylindrical cavity bored through the center. A cylindrical permanent magnet magnetized normal to the cylinder axis is rotatably disposed in the cavity. An actuator allows rotation of the permanent magnet to any angle, which rotation changes the distribution of flux in the magnetic circuit through the pole pieces. Thus, one can control field intensity in the gaps by positioning the permanent magnet at whatever angle provides the required field strength. Because the field also passes above the pole pieces, defining a fringing field outside the wheel surface, the variable field extends through a layer of MR fluid on the wheel, thus varying the stiffness of the MR fluid as may be desired for finishing control.
摘要:
A system for magnetorheological finishing of a substrate. An integrated fluid management module (IFMM) provides dynamic control of the rheological fluid properties of the MR fluid on a conventional MR finishing apparatus, and dispensing of the fluid to the wheel. A magnetically shielded chamber charged with MR fluid is in contact with the carrier wheel. A transverse line removes the spent MR fluid from the wheel as the ribbon leaves the work zone. Replenishment fluid is added to the chamber via a dripper, and preferably an electric mixer agitates MR fluid in the chamber. A grooved magnetically-shielded insert at the exit of the chamber forms a polishing ribbon on the carrier wheel as the wheel is turned. A sensor sensitive to concentration of magnetic particles provides a signal for control of MR fluid properties, particularly, water content in the MR fluid. Means is provided for cooling fluid within the chamber.
摘要:
An edge finishing apparatus includes a surface, a fluid delivery device configured to deliver at least one magnetorheological polishing fluid (MPF) ribbon to the at least one well, at least one magnet placed adjacent to the surface to selectively apply a magnetic field in a vicinity of the surface, and at least one holder placed in opposing relation to the surface, the at least one holder being configured to support at least one article such that an edge of the at least one article can be selectively immersed in the MPF ribbon delivered to the at least one well.
摘要:
A method of finishing an optical element includes mounting the optical element in an optical mount having a plurality of fiducials overlapping with the optical element and obtaining a first metrology map for the optical element and the plurality of fiducials. The method also includes obtaining a second metrology map for the optical element without the plurality of fiducials, forming a difference map between the first metrology map and the second metrology map, and aligning the first metrology map and the second metrology map. The method further includes placing mathematical fiducials onto the second metrology map using the difference map to form a third metrology map and associating the third metrology map to the optical element. Moreover, the method includes mounting the optical element in the fixture in an MRF tool, positioning the optical element in the fixture; removing the plurality of fiducials, and finishing the optical element.
摘要:
This invention provides a polishing apparatus using a polishing material freely varying its shape in a tri-dimensional space in accordance with the shape of a work, and capable of polishing a narrow, recessed surface inaccessible to human hands or a tool, and a polishing method used therefor. A fluid containing grinding particles is solidified or gelatinized in accordance with the shape of a work; and the resulting solid body is moved relative to the work, thereby polishing or grinding the work. The fluid containing grinding particles is a magnetic fluid capable of controlling the orientation of grinding particles in the presence of a magnetic field; and the fluid is solidified or gelatinized while being exposed to a magnetic field. Alternatively, the grinding particles are dielectric grinding particles capable of polarizing in the presence of an electric field, and the fluid containing dielectric grinding particles is solidified or gelatinized while being exposed to an electric field. Further, a fluid containing grinding particles is poured on the surface of a work to be processed; and the fluid is solidified or gelatinized while it takes a shape in accordance with that of the surface of work to be processed, thereby producing a polishing material. A fluid containing grinding particles is solidified or gelatinized while it takes a shape in accordance with that of a work; and the resulting solid is moved relative to the work, thereby polishing or grinding the work.
摘要:
A magnetic wiper for removing magnetorheological fluid from a carrier surface includes a horseshoe magnet having north and south polepieces elongated in a first direction orthogonal to a second direction of magnetic flux in the magnet. The polepieces are generally parallel at their free ends in the first direction and are preferably arcuate such that the inner polepiece forms a trough for receiving magnetorheological fluid removed from the carrier surface and conveying it to an exit tube. The free ends are shaped to conform closely to the shape of the carrier surface, forming a narrow gap therebetween containing a magnetic fringing field extending beyond the free ends. Magnetorheological fluid conveyed into the gap by the carrier surface is magnetically stiffened to a very stiff paste which is retained in the gap by the fringing field, forming a dynamic liquid seal such that additional magnetorheological fluid carried by the carrier surface is wiped away from the surface and into the trough formed by the inner polepiece. Thus, the magnet forms an effective remover of magnetorheological fluid from the carrier surface without any mechanical contact with the surface.
摘要:
The present invention provides a method for processing such as deburring, polishing and washing of surfaces of slits of a workpiece, having slits with narrow width from outer surface toward inside, with high accuracy and high efficiency. Magnetic abrasive material is retained in a magnetic field formed between magnetic poles 3 and 4, and magnetic brushes 5 are formed. A workpiece 1 made of non-magnetic material and having slits 1f with narrow width is placed in said magnetic brushes 5, and by relatively vibrating said magnetic poles and said workpiece, surfaces of the slits are processed. It is more effective to tilt the slit surface with respect to the magnetic field after the slit surface is arranged in parallel to the magnetic field.
摘要:
An improved system for increasing the effectiveness of magnetorheological finishing of a substrate. An inline flowmeter is close-loop linked to the rotational speed of a pressurizing pump to assure that the flow of magnetorheological fluid (MRF) to the work zone is constant. A simplified capillary viscometer is disposed in the fluid delivery system at the exit thereof onto the wheel surface. Output signals from the flowmeter and the viscometer pressure sensor are sent to a computer which calculates the viscosity of MRF being delivered to the work zone and causes replenishment of carrier fluid to the work-concentrated MRF to return the viscosity to aim to assure that a constant concentration of magnetic solids is being provided to the work zone. Asymmetric pole pieces for the field magnet at the work zone extend the magnetic field along the wheel surface upstream of the work zone to permit full magnetic stiffening of the MRF before it engages the work piece, while minimizing fringing field in the vicinity of the viscometer, and to shorten the magnetic field along the wheel surface downstream of the work zone.
摘要:
The method envisages measuring strip tension and computing the difference between tensions at the inlet to and outlet from each descaling zone, comparing this difference is strip tension with a preset difference, and compensating for deviations in strip tension from the preset difference by varying the pressure exerted by the powder on the strip in each descaling zone.