42 results about "Magnetorheological finishing" patented technology

The invention relates to a dynamic magnetic field self-sharpening finishing device for a flexible magnetorheological finishing pad and a finishing method for the dynamic magnetic field self-sharpening finishing device. The dynamic magnetic field self-sharpening finishing device comprises a finishing disk revolution mechanism and a multi-magnetic-pole synchronous rotation driving mechanism, wherein the finishing disk revolution mechanism comprises a driving shaft motor, a drive shaft, an adapting disk, an eccentric shaft fixing disk, a cup-like finishing disk and a driving shaft transmission mechanism; the multi-magnetic-pole synchronous rotation driving mechanism comprises an eccentric spindle, synchronous rotation driving plates, flexible eccentric rotating shafts, eccentric sleeves, magnetic poles, the eccentric shaft fixing disk, a spindle motor and the like. According to the finishing device and the finishing method disclosed by the invention, the conditions that a circulating device is adopted for updating magnetorheological fluid and the magnetorheological fluid is changed in the processing process are avoided, so that the space is saved, and the whole process from rough finishing to fine finishing can be realized by one-time processing; obtained workpieces are good in surface consistency, high in processing efficiency, free from of surface and subsurface damage and low in cost, so the finishing device and the finishing method are suitable for high-efficiency ultra-smooth uniform finishing processing of planes of large-diameter optical elements; meanwhile, the finishing device and the finishing method disclosed by the invention are also suitable for experimental researches such as a material removing mechanism and subsurface damage detection of optical planar materials.

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.

A method of preparing an edge-strengthened article comprises polishing of an edge of an article having a first edge strength using magnetorheological finishing, wherein after the polishing the article has a second edge strength and the second edge strength is greater than the first edge strength.

The invention discloses a constant pressure ultrasonic wave aiding magnetorheological finishing method and a constant pressure ultrasonic wave aiding magnetorheological finishing device. The method includes the steps of firstly, mounting a workpiece on a double-rotating workbench; secondly, adjusting distance between a small ball milling head and the workpiece to allow a clearance to be formed between the two, and setting a threshold P1 and a threshold P2 of a force cell at an extending position of an electromagnetic coil iron core mounted above the small ball milling head through a control system; thirdly, starting a spindle to drive the small ball milling head to rotate, simultaneously starting an ultrasonic wave vibrating device to allow ultrasonic vibration of the small ball milling head, and jetting magnetorheological fluid in the clearance formed by the small ball milling head and the workpiece through an output pipeline; and fourthly, repeatedly finishing the workpiece according to the surface shape of the to-be-machined workpiece until the machining of the workpiece is completed. Accurate point removing can be performed on the workpiece surface by the method.

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.

The invention relates to a magneto-rheological polishing device suitable for ultra-large aperture optical processing, comprising: a magneto-rheological fluid polishing device, which includes a magnet device capable of providing a magnetic field; a horizontal protruding section is provided at the lower end of the magnet device; The variable fluid circulation device can make the magneto-rheological fluid circulate through the horizontal protrusion section, and form ribbon protrusions under the action of a magnetic field perpendicular to the flow direction. The invention provides a magneto-rheological polishing device suitable for ultra-large-diameter optical processing, which can be rebuilt on a polishing machine tool, and can replace the polishing head of the polishing machine tool, such as a stress plate, a small grinding head, etc., without changing the original mechanical structure of the machine tool. The magnetorheological polishing device of the present invention not only reduces the volume of the system, simplifies the mechanical structure, but also increases the material removal efficiency, thereby solving the problems of low removal efficiency and long processing cycle of the current large-diameter aspheric surface.

The invention discloses a manufacturing method for preparing a composite particle from a ferromagnetic particle and an abrasive material for magnetorheological finishing. In particular, the surface ofthe ferromagnetic particle is wrapped with the abrasive material, or the abrasive material is embedded into the surface of the ferromagnetic particle; when the composite particle prepared from the ferromagnetic particle and the abrasive material encounters a magnetic field, the composite particle is arrayed by the action of a magnetic force line to form a self-adaptive flexible solid; and when the magnetic field moves, the composite particle moves with the magnetic field. When the movable self-adaptive flexible solid comprising the composite particle acts on the surface of a workpiece, the abrasive material compounded on the surface of the ferromagnetic particle generates an abrading or finishing effect on the surface of the workpiece. The effect of finishing is correspondingly changed with presence and intensity of the magnetic field. That is to say, the finishing is the magnetorheological finishing. The composite particle comprising the ferromagnetic particle and the abrasive material can perform dry abrading and finishing on the workpiece and be put in carrier liquid (including water-based liquid, a solvent or oil-base liquid and assistants of the water-based liquid, the solvent or the oil-base liquid) for the wet magnetorheological finishing of the workpiece.

The invention discloses a magneto-rheological polishing device for large-diameter aspheric optical parts, which includes a machine tool, a polishing device, a magnetorheological polishing liquid circulation system for providing stable performance polishing liquid, and the components connected with the above components For the control system, the machine tool has four or more degrees of freedom, and the polishing device is fixed on the machine tool and located directly above the workpiece to be processed on the machine tool. The invention is a magnetorheological polishing device for large-diameter aspherical optical parts with simple and compact structure, low cost, simple control, wide application range and strong processing ability.