Patent
Rotational abrasive micro/nano-finishing
| العنوان: | Rotational abrasive micro/nano-finishing |
|---|---|
| Patent Number: | 10201,885 |
| تاريخ النشر: | February 12, 2019 |
| Appl. No: | 15/338382 |
| Application Filed: | October 29, 2016 |
| مستخلص: | Disclosed herein is a method for inner surface finishing of a workpiece, in which the inner surface of the workpiece defines an opening with axial symmetry around the longitudinal axis of the workpiece. The method may include the following steps. An abrasive medium may be poured inside the opening; urging the abrasive medium to rotate about the longitudinal axis, thereby imposing a centrifugal force on the abrasive medium to accelerate the abrasive medium outwards from the center of rotation towards the inner surface of the opening, where the abrasive medium impacts the inner surface of the opening; and the workpiece may be rotated about the longitudinal axis in a direction opposite the first direction, concurrently. |
| Inventors: | Azami Gilan, Aref (Kermanshah, IR); Azizi, Abdolhamid (Ilam, IR) |
| Claim: | 1. A method for inner surface finishing of a workpiece, wherein the inner surface of the workpiece includes an opening with axial symmetry around a longitudinal axis of the workpiece, the method comprising: pouring an abrasive medium between blades inside the opening; rotating the abrasive medium about the longitudinal axis in a first direction within the opening, thereby imposing a centrifugal force on the abrasive medium to accelerate the abrasive medium outwards from the center of rotation towards the inner surface of the opening, wherein the abrasive medium impacts the inner surface; and concurrently rotating the workpiece about the longitudinal axis in a second direction, wherein the first direction is opposite the second direction. |
| Claim: | 2. The method according to claim 1 , wherein the abrasive medium is a mixture of processing oil and nanoparticles. |
| Claim: | 3. The method according to claim 2 , wherein the nanoparticles are selected from the group consisting of boron carbide (B 4 C), silicon carbide (SiC), and combinations thereof. |
| Claim: | 4. The method according to claim 1 , wherein imposing the centrifugal force to the abrasive medium includes utilizing a rotor to accelerate the abrasive medium outwards from the center of rotation. |
| Claim: | 5. The method according to claim 4 , wherein the rotor is an impeller with blades of various shapes. |
| Claim: | 6. An apparatus for inner surface finishing of a workpiece, wherein the inner surface defines an opening inside the workpiece with axial symmetry around a longitudinal axis of the workpiece, the apparatus comprising: a fixture configured to house and grip the workpiece; a stirrer having a central shaft and a plurality of radially extending blades connected to the central shaft and rotatable therewith, wherein the blades are disposed within the opening defined by the inner surface of the workpiece; a first rotary actuator coupled to the central shaft and configured to drive a rotational movement of the stirrer about the longitudinal axis in a first direction; and a second rotary actuator coupled with the fixture and configured to drive a rotational movement of the fixture about the longitudinal axis in a second direction, wherein: the first direction is opposite the second direction; the abrasive medium is poured between the blades, inside the opening; and the stirrer is configured to accelerate the abrasive medium outwards form the center of rotation towards the inner surface of the opening. |
| Claim: | 7. The apparatus according to claim 6 , wherein the radially extending blades have a proximal edge and a distal edge, wherein the proximal edge is configured to be connected to the central shaft and the distal edge is shaped such that the horizontal distance between the distal edge and the inner surface of the opening is constant along the vertical length of the blades defining a working gap. |
| Claim: | 8. The apparatus according to claim 7 , wherein the working gap defines a contact zone for abrasive medium to rotate and impact the inner surface of the opening to perform surface finishing operation. |
| Claim: | 9. The apparatus according to claim 6 , further comprising an upper cap and a lower cap placed at either sides of the workpiece and tightly fixed thereon, configured to retain the abrasive medium inside the opening. |
| Claim: | 10. The apparatus according to claim 9 , wherein the upper cap is configured with a central opening for the central shaft to pass through. |
| Claim: | 11. The apparatus according to claim 8 , wherein the stirrer, the upper and lower caps are coaxially placed around the longitudinal axis of the workpiece without any eccentricity. |
| Claim: | 12. The method according to claim 4 , wherein rotating the abrasive medium about the longitudinal axis in a first direction within the, opening comprise rotating the abrasive medium by rotating the impeller placed within the opening. |
| Claim: | 13. The method according to claim 1 , wherein concurrently rotating the workpiece comprises rotating a fixture corresponding to shape of surface of the workpiece, wherein the workpiece is coupled to the fixture. |
| Patent References Cited: | 6688953 February 2004 Kawasaki 6905395 June 2005 Walch 6962522 November 2005 Kawasaki 2014/0220869 August 2014 Tzeng 100546764 October 2009 102501179 September 2013 2699/DEL/2011 October 2011 100257847 June 2000 |
| Other References: | Mamilla Ravi Sankar, Experimental investigations into rotating workpiece abrasive flow finishing, Wear , Nov. 2008, vol. 267, pp. 43-51. cited by applicant Mamilla Ravi Sankar, Rotational abrasive flow finishing (R-AFF) process and its effects on finished surface topography, International Journal of Machine Tools & Manufacture, Mar. 2010, vol. 50, pp. 637-650. cited by applicant R. S. Walia, Morphology and integrity of surfaces finished by centrifugal force assisted abrasive flow machining, Journal of advance manufacturing technology, Dec. 2007, vol. 39, pp. 1171-1179. cited by applicant V.K. Jain, Magnetic field assisted abrasive based micro-/nano-finishing, Journal of Materials Processing Technology , 2009, vol. 209, pp. 6022-6038. cited by applicant Biing-Hwa Yan, Finishing effects of spiral polishing method on micro lapping surface, International Journal of Machine Tools & Manufacture, Oct. 2006, vol. 47, pp. 920-926. cited by applicant |
| Primary Examiner: | Rose, Robert |
| Attorney, Agent or Firm: | Bajwa IP Law Firm Bajwa, Haris Zaheer |
| رقم الانضمام: | edspgr.10201885 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |