US2883809A

US2883809A - Polishing apparatus

Info

Publication number: US2883809A
Application number: US698015A
Authority: US
Inventors: Luther G Simjian
Original assignee: Reflectone Corp
Current assignee: Reflectone Corp
Priority date: 1957-11-21
Filing date: 1957-11-21
Publication date: 1959-04-28
Anticipated expiration: 1976-04-28

Description

April 8, 1959 L. G. SIMJIAN 2,883,809

POLISHING APPARATUS Filed vNOV. 21, 1957 LUTHER G. SI MJIAN INVENTOR.

United States Patent POLISHING APPARATUS Luther G. Simjian, Greenwich, Conn., assignor to The Reflectone Corporation, Stamford, Conn., a corporation of Connecticut Application November 21, 1957, Serial No. 698,015

7 Claims. (Cl. 51-281) This invention relates to polishing and has particular reference to the polishing of the surfaces of articles which are formed with re-entrant cavities and other surfaces that are diflicult to polish by the usual rigid or semi-rigid polishing means. The invention is particularly related, as set forth below, to those inventions described in my U.S. Letters Patent No. 2,735,231 granted February 21, 1956, and No. 2,735,232, dated February 21, 1956.

This application is itself a continuation-in-part of my application for patent, No. 566,571, filed February 20, 1956, now abandoned, in that I disclose in this application the method as Well as the apparatus set forth in said application Serial Number 566,571. Since I disclose in application 566,571 and also in this application, the method first described in my application resulting in Patent No. 2,735,231, supra, granted February 21, 1956, with which said earlier application 566,571 was co-pending. There are therefore in this application claims covering the method disclosed in said Patent No. 2,735,231. Further, the method claims of this application cover also the methods set forth in Patent No. 2,735,232, supra, as well as my further Patent No. 2,787,854, granted April 9, 1957.

My invention is further related to that set forth in my application Serial No. 689,569 dated October 11, 1957, for an Abrading Device. In this last application a plurality of parts to be abraded are so abraded while held in a fluent bath merely by the magnetized particles of the bath, although in one form of the invention, other support means are shown.

In general machine shop practice, polishing is accomplished by an operator using a bufling wheel which is rotated at high speed and which has been impregnated with a polishing compound. It is well known that such a device gives fast and satisfactory results only on fiat or convex surfaces. Concave surfaces, however, are more difficult to polish with a polishing wheel and small holes and cavities cannot be handled at all using this conventional polishing means. The present invention can be used to polish almost any sort of surface including plane surfaces, holes, and other cavities, and does not require the use of an operator.

In a typical embodiment, the present invention utilizes a container that contains a mixture of abrasive magneic particles and a liquid. The article to be polished or abraded is immersed in the mixture at a time when said mixture is not subjected to magnetic lines of force, or when said magnetic lines of force are so weak that said mixture is fluent. Naturally, when the mixture is subjected thereafter to magnetic lines of force, it becomes non-fluent in proportion to the magnetization of said magnetic lines of force, and is operable to abrade the article immersed therein. In the particular apparatus set forth in this application, the article to be polished or abraded, once applied to the mixture, is moved in and out of said mixture, or relatively to it. Naturally, movement relatively to the mixture of the article when the mixture is relatively less fluent, will bring about an Patented Apr. 28, 1959 abrading action, the degree of solidification or hardening of the mixture being controlled by means of a magnetic field applied to the mixture.

Naturally, there can be intermediate conditions of the mixture as will be appreciated by those skilled in the art. The more intense the magnetic lines of force, naturally, the harder will be the mixture. By synchronizing the mechanical motion of the object, and the application of the magnetic field to the mixture in such a manner that the consistency of the mixture is increased whenever the article is moved relatively to the mixture or otherwise manipulated relatively thereto, and immersing the article into the mixture when the mixture is substantially liquid or otherwise more fluent than before, the surface of the article becomes polished. Since the mixture will readily follow the contours of the object when fluent, it is apparent that surfaces of gears, jewelry, plastic molds and of many other articles can be polished in a convenient, economic manner.

One of the objects of this invention is to provide an improved polishing device which avoids one or more of the disadvantages and limitations of prior art arrangements.

Another object of the invention is to polish objects having small cavities.

Another object of this invention is to polish complex structures with complete safety to the operator.

Another object of this invention is to polish an object without the aid of rotating wheels or belts.

Another object of the invention is to provide a polishing operation which is automatic and does not require the skill and judgment of a trained operator.

Another and further object of the invention is the provision of a polishing apparatus which produces uniform results.

A still further object of the invention is the provision of a polishing device which readily can be adjusted for various conditions of hardness, of speed and surface characteristics.

The basic feature of my invention is the control through magnetism of a bath of abrasive material that is fluent when not magnetized, but which is rendered non-fluent to varying degrees when subjected to magnetic lines of force, all for the purpose of abrading an article. The article to be abraded is placed in the bath of abrasive material when the bath is not substantially magnetized and is at least sufliciently fluent for the placing of the article in the bath with the abrasive material of the bath moving into the recesses of the article to be abraded or polished. Thereafter, relative motion between the article and the bath effects the abrading action, it being, of course, possible to obtain this relative motion by many means including actual motion of the particles of abrasive material as the mixture is magnetized.

For a better understanding of the present invention together with other and further objects thereof reference is made to the following description taken in connection with the accompanying drawing in which the figure is a cross-sectional view of the polishing device, illustrating one typical embodiment.

Referring now to the figure, a container 10 preferably made of non-magnetic material is employed, filled with a mixture 11 which comprises abrasive magnetic particles, such as iron filings, steel powder, powdered Alnico material, etc. mixed with a liquid, as for instance oil. In proximity to said container there is located a magnetic core 12 having an electromagnetic coil 13 mounted thereon which when energized with electric current establishes a magnetic flux through the mixture 11 so as to solidify it or increase its consistency.

Within said mixture 11 and intersecting the magnetic field, there is disposed an object, the surface of which is to be polished, such as three spur gears 14, which are retained on a stud 15. This stud is moved vertically by means of a motor 16 driving a wheel 17 connected via pin 18 to a connecting rod 19 and coupling pin means 20.

The container and magnetic parts are surrounded by a housing 21 which is equipped with a top cover 22 in which there is disposed a bearing 23 which serves to guide stud 15 in vertical position.

In synchronism with the motion of Wheel 17 there is being driven a cam 30 which is employed to actuate an electrical circuit switch 31. This circuit switch 31 serves as timing switch to energize electromagnetic coil 13 when the object is raised from the mixture and to deenergize the coil when the object is lowered. In this manner, when the object is moved out of the mixture, the magnetic particles by virtue of the magnetic field are urged in intimate contact with. the object and because of the increase of consistency of the mixture, an abrading action of the particles against the object surface is achieved. In the conventional manner, drive motor 16 is energized from a source of energy 35 via a control switch 34. Similarly the electric circuit to the electromagnetic coil includes a source of energy 36 and a control switch 37.

It will be apparent to those skilled in the art that the instant device is well suited for polishing complex surfaces since the mixture will shape itself to follow the contours of the object. By varying the particle size of the mixture, the intensity of the magnetic field, etc. a great variety of conditions is achieved to satisfy the great majority of prevalent conditions.

While there have been described certain embodiments of the instant invention, it will be apparent to those skilled in the art that various other modifications may be made without departing from the spirit of the present invention which should be limited only by the scope of the appended claims.

What is claimed is:

1. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable fluent material at a time when said magnetizable material is not magnetized and is therefore fluent to permit the insertion of the article thereinto with the surfaces of the article to be abraded inundated in said bath, magnetizing said fluent material to render the bath non-fluent with the magnetizable material in intimate contact with the surfaces of the article to be abraded, and thereafter de-magnetizing and magnetizing said bath at predetermined intervals with the article movable in said bath relatively to said fluent material while said fluent material is not magnetized.

2. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable fluent material at a time when said magnetizable material is in that magnetic state rendering it sufliciently fluent to permit the insertion of the article thereinto with the surfaces of the article to be abraded inundated in said bath, magnetizing said fluent material to render the bath relatively non-fluent with the magnetizable material held in intimate contact with the surfaces of the article to be abraded, and thereafter de-magnetizing and magnetizing said bath to a predetermined degree at predetermined intervals.

3. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable abrasive fluent material at a time when said magnetizable material is in that magnetic state rendering it sufficiently fluent to permit the insertion of the article thercinto with the surfaces of the article to be abraded inundated in said bath, and the abrasive material flowing into intimate contact with interior surfaces to be abraded, magnetizing said fluent material to render the bath nonfluent with the magnetizable material held in intimate contact with the surfaces of the article to be abraded, and moving said article and said magnetized fluent material relatively to one another.

4. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable fluent material, applying magnetic lines of force to said fluent material to render the bath less fluent than prior to the application of said magnetic lines of force and in proportion to the strength of the magnetic force so applied thereto, with the magnetizable material in intimate contact with the surfaces of the article to be abraded, and moving said article and said magnetized fluent material relatively to one another.

5. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable abrasive fluent material at a time when said magnetizable material is in that magnetic state rendering it sufficiently fluent to permit the insertion of the article thereinto with the surfaces of the article to be abraded inundated in said bath, and the abrasive material moving into intimate contact with the surfaces to be abraded, applying magnetic lines of force to said magnetized fluent material to render the bath less fluent in accordance with the strength of said magnetic lines of force, and moving the article and abrasive material relatively to one another to effect the abrading action.

6. The method of abrading the surface of an article that comprises placing the article in a bath of magnetizable abrasive fluent material at a time when said magnetiz able material is in that magnetic state rendering it sufliciently fluent to permit the insertion of the article thereinto with the surfaces of the article to be abraded inundated in said bath and the abrasive material moving into intimate contact with the surfaces to be abraded, magnetizing said fluent material to hold the magnetizable abrasive material firmly in intimate contact with the surfaces of the article to be abraded, and moving the article and said abrasive material relatively to one another to effect the abrading action.

7. The steps in the method of abrading the surface of an article that comprise placing the article in a bath of magnetizable fluent material at a time when said magnetizable fluent material is in that magnetic state rendering it sufiiciently fluent to permit the insertion of the article thereinto with the surfaces of the article to be abraded inundated in said bath, and the abrasive material flowing into intimate contact with interior surfaces to be abraded, and thereafter magnetizing said fluent material to hold the magnetizable material in said intimate contact with the surface of the article to be abraded whereby to make possible the abrading of said surfaces.

References Cited in the file of this patent UNITED STATES PATENTS 2,735,231 Simjian Feb. 21, 1956 2,735,232 Sirnjian Feb. 21, 1956 2,796,702 Bodine June 25, 1957