APPARATUS AND METHOD FOR BURNISHING METAL OBJECTS
United States Patent 3680266
A vibratory burnishing machine includes a drum which is supported on a table for vibratory movement. A frame on the drum includes a rotating counterweight which during rotation imparts vibratory movement to the drum. The vibratory movement is imparted to burnishing media in the form of steel balls or shot which burnish metal articles within the drum. The machine is particularly adapted for polishing small articles of flat and circular configuration such as coins by the combination of an open end cylinder which is freely moveable in the drum in response to movement of the burnishing media.
US Patent References:
Apparatus for cleaning elongated metal objects
Hilbish et al. - October 1939 - 2174879
Apparatus for cleaning elongated metal objects
Hilbish et al. - October 1939 - 2174879
Application Number:
05/115615
Publication Date:
08/01/1972
Filing Date:
02/16/1971
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
451/330, 366/112
International Classes:
B24B31/06; B24B31/00; B24B31/00
Field of Search:
259/72,DIG.42 51/7,163,313,317,164 29/90
Primary Examiner:
Hosar, Francis S.
Claims:
What is claimed is
1. A vibratory burnishing apparatus including;
2. The invention in accordance with claim 1,
3. The invention in accordance with claim 2,
4. The invention in accordance with claim 2,
5. The invention in accordance with claim 4,
6. The invention in accordance with claim 5,
7. The invention in accordance with claim 1,
8. The invention in accordance with claim 7,
9. The invention in accordance with claim 7,
10. A method of burnishing metal articles of relatively small size comprising the steps of;
11. The method in accordance with claim 10,
12. The method in accordance with claim 11,
13. A vibratory burnishing apparatus including;
14. The invention in accordance with claim 13,
15. The invention in accordance with claim 14,
16. The invention in accordance with claim 1,
17. In a burnishing apparatus,
18. The method of polishing objects comprising the steps of:
19. placing a burnishing media in the form of a plurality of burnishing elements within a burnishing drum,
20. placing an aperture hollow turbulence creating member in the burnishing drum,
21. causing movement of the burnishing media within the drum whereby the apertured member moves within an orbital path within the movement of the burnishing media resulting in a turbulent dispersal of the media in and out of the member within the drum, and
22. subjecting objects to be burnished To such turbulent media.
1. A vibratory burnishing apparatus including;
2. The invention in accordance with claim 1,
3. The invention in accordance with claim 2,
4. The invention in accordance with claim 2,
5. The invention in accordance with claim 4,
6. The invention in accordance with claim 5,
7. The invention in accordance with claim 1,
8. The invention in accordance with claim 7,
9. The invention in accordance with claim 7,
10. A method of burnishing metal articles of relatively small size comprising the steps of;
11. The method in accordance with claim 10,
12. The method in accordance with claim 11,
13. A vibratory burnishing apparatus including;
14. The invention in accordance with claim 13,
15. The invention in accordance with claim 14,
16. The invention in accordance with claim 1,
17. In a burnishing apparatus,
18. The method of polishing objects comprising the steps of:
19. placing a burnishing media in the form of a plurality of burnishing elements within a burnishing drum,
20. placing an aperture hollow turbulence creating member in the burnishing drum,
21. causing movement of the burnishing media within the drum whereby the apertured member moves within an orbital path within the movement of the burnishing media resulting in a turbulent dispersal of the media in and out of the member within the drum, and
22. subjecting objects to be burnished To such turbulent media.
Description:
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to the art of burnishing or polishing machines.
2. Description of the Prior Art
The prior art relates to burnishing machines which are especially adapted to polishing metal parts which include a vessel or drum containing a burnishing media generally consisting of small steel balls and a burnishing compound. Such machines are suitable for polishing silver or other metals simply by placing the articles in the vessel and subjecting them to the vibration of the burnishing media. Certain of the machines include fixtures which moveably support the parts to be burnished.
SUMMARY OF THE INVENTION
It is a prime object of the present invention to provide an improvement to a conventional burnishing or polishing machine which permits the utilization of the machine as an apparatus, and in a method, for polishing small flat cylindrical or circular metal articles such as coins. The machine includes a conventional drum which is mounted for vibratory movement on a table. The drum has an arcuate bottom and contains burnishing balls and a conventional comPound which may be liquid, is directed to and from the vessel in a re-circulatory cycle. Such a system is disclosed in the D. E. Roberts U.S. Patent No. 3,353,796, patented Nov. 21, 1967. In the present invention a cylindrical open end member is freely dispersed within the drum to move in response to vibration with the balls in a circulatory path which adapts that machine for the efficient and effective burnishing of relatively small flat objects such as coins. Thus the machine is particularly effective for coin polishing or the like.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of a vibratory drum mounted on a table;
FIG. 2 is a cross sectional view taken particularly along the line of 2--2 of FIG. 1;
FIG. 3 is a perspective view of an open end cylinder; and;
FIG. 4 is a cross sectional view of a modified drum arrangement including means for discharging burnishing balls from the drum.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 discloses a vibratory machine generally designated at 10 which includes a suitable table 11 having an opening 12 within which a work drum 13 is supported. The drum 13 is provided with an arcuate or semi-cylindrical wall 14 and opposite side walls 15. The walls 14 and 15 are provided with a conventional rubber-like liner designated at 16. Brackets 17 project outwardly at upper opposite ends of the drum 13 and suitable spring means 18 support the drum 13 on the table 11 to provide for vibratory movement of said drum 13. A suitable nozzle 19 is provided which will direct a liquid burnishing compound to the drum and which may be pumped therefrom in a circulatory system from an outlet fitting 20.
The drum 13 has connected thereto a frame 21 comprising vertical plates 22 which are interconnected at their lower portion by a suitable support bracket 23. An electric motor 24 is mounted on the bracket 12 and includes a drive pulley which by means of a belt 26 drives a driven pulley 27 mounted on a shaft 28 which is suitably supported on the plates 22 for rotation. One or more counterweights 29 are connected to the shaft 28 for rotation therewith and during rotation impart vibratory movement to the drum 13. The motor need not necessarily be mounted on the frame 21 but can be mounted on a suitable table frame (not shown). This type of machine is conventional as disclosed in the Ferrara U.S. Pat. No. 3,464,163 patented Sept. 2, 1969.
As best shown in FIG. 3, a cylinder 30 includes a plurality of openings 31 and the cylinder 30 is open at opposite ends. The openings 31 may be of various sizes and shapes to freely permit the burnishing media in the form of steel balls 32 and the liquid compound to flow freely therethrough during the burnishing operation. As indicated in the Figures, a charge of monetary coins 33 is placed in the drum 13 to be subjected to the burnishing or polishing operation.
In the modification shown in FIG. 4 the machine is identical to that above described. However in addition the drum 13 is provided with means permitting the burnishing balls 32 to be discharged from the drum and thereby the coins 33 are retained therein so that they can be easily removed. In this modification the drum 13 includes a plurality of openings 34 which extend throuGh the wall 14 and through the adjacent liner 16. The openings 34 are of a size so that the balls 32 can easilY pass therethrough but are small enough to prevent the smallest coin burnished from passing from the drum 13.
A cover 35 is hingedly connected as indicated at 36 to the wall 14 and the same is shown in the open position. The cover 35 includes a suitable gasket 37 which is in the closed position, shown in broken lines sealingly covers the openings 34. A latch element 38 may be rotated over the cover 35 to tightly maintain the cover in it's latched or closed position. A chute 39 is placed in position between the plates 22 for directing the discharged balls 32 into a container 40 carried on a support 41.
OPERATION
In conventional fashion the rotation of the counterweight 29 causes vibratory movement of the drum 13 and the balls 32 contained therein. Simultaneously burnishing compound is recirculated from a suitable pump and reservoir not shown from the nozzle 19 through the drain fitting 20. The counterweights 29 are so positioned to create within the drum an orbital flow of the media as indicated by the arrows.
The cylinder 30 is placed in the drum as shown in FIG. 2, with its axis extending normal to the side walls 15. A charge of coins 33 is now placed into the drum 13. During vibration the coins, balls, and cylinder move in a direction as indicated by the arrows in FIG. 1. This may be described as an orbital or circular path flow, the parts within the drum arriving at the top on the left hand side and then flowing in an arcuate path to the right downwardly to the bottom of the drum, then arcuately again to the top. At the same time the flow of the balls imparts a rOtating movement to the cylinder 30 about its own axis, and also in a smaller orbital movement to remain in a more submerged position relative to the balls and simultaneously dragging coins with the balls downwardly toward the bottom of the drum where the most effective burnishing action occurs.
The cylinder is preferrably of a suitable steel, though other metals or materials may be utilized. By dimensioning the cylinder ends approximatelY relative to the side walls 15 as shown, stability of the same is maintained against substantial variation from the transverse rotational axis diSclosed.
It has been determined that the efficiency of burnishing of the coins is greatly increased, both from a quality and time standpoint, by the utilization of the freely dispersed or floating cylinder. Some of the coins may pass thru the openings 31 and then transversely through the cylinder intermingled with the burnishing balls and thus are subjected to a slide zone action. This action is created in tumbling machines which have also been utilized for the burnishing of materials. Thus the vibratory action of the balls is supplemented by a slide zone or bumbling action of the cylinder and greatly improved results are obtained. Thus the movement of the media is thru the openings 31 normal to the cylinder axis and then along said axis outwardly from the opposite open ends of the cylinder. The apertures or openings 31 also permit the balls 33 to freely pass therethrough and yet are small enough to prevent the coins from passing. Further the cylinder prevents the coins from adhering to each other which will occur without the cylinder and thus retard proper and effective burnishing. The cylinder during rotation also is effective to prevent the balls and coins from being thrown out of the drum during heavy loading of the drum. Thus more coins can be effectively processed.
The process of burnishing thus includes the steps of vibrating the balls within the drum wherein the vibratory motion is imparted to the coins which flow in a circular, or orbital path with the balls and the cylinder. The cylinder during such vibration also is freely carried in said circular, or orbital, path and rotates about it's own axis, in it's own orbit, thereby imparting a sliding action, such as occasioned by tumbling, to the burnishing media and the coins carried therein.
The arrows in FIG. 1 describe the rotation of the mass of media, cylindrical members and the charge of materials. As indicated above, the semi-cylindrical shape of the drum and the off-center positioning of the counterweight causes this flow in what is termed as an orbit or orbital movement. This is conventional. However, in the present process a portion of the media is treated to a separate smaller diameter orbit within the freely rotating cylindrical member, which second orbit moves with the cylinder in the firSt orbit. Media and a portion of the charge is temporarily confined in this smaller orbit, subjected to the burnishing tumbling action, is discharged from the cylindrical member and additional material as portions of the mass are then so treated.
The cylindrical member is also effective, by virtue of the apertures, or openings 31, through which the balls pass to agitate the mass of media and thus increase the effectiviness of the operation without all of the coins necessarily passing through the cylinder. As indicated in the operation hereinabove the passage of the steel balls through the cylinder is believed to be the primary causative factor for the improved operation. External visual observation indicates a phenomena occurring which provides for the increased effectiveness of the burnishing balls. The eccentric vibratory or oscillating of the drum causes the balls to move in an orbital flowing pattern and in a fluid like manner, the balls entering in the apertures of the cylinder and out from the opposite ends thereof. This creates a turbulence within the mass of balls below the upper surface thereof with the balls being moved by the drum to vary the density of a plurality of the balls in various places in the drum to create a multi-convectional flow of the burnishing balls. This results in increased contact of the balls with the coins resulting in a greater polishing effect in a shorter time. This increased polishing effect is present throughout the drum because the cylinder is carried in the orbital path in the drum and is in an orbit of its own, so that the balls are carried also in an orbital path around the cylinder.
After a certain period of operation, the door 37, in the modification of FIG. 4, is opened. The recirculation of liquid compound has been stopped and the vibration is continued until the majority of the balls have been discharged through the openings 34 thru the chute 39 and the container 40. The coins remain in the drum and these may now be gathered and removed.
1. Field of Invention
This invention relates to the art of burnishing or polishing machines.
2. Description of the Prior Art
The prior art relates to burnishing machines which are especially adapted to polishing metal parts which include a vessel or drum containing a burnishing media generally consisting of small steel balls and a burnishing compound. Such machines are suitable for polishing silver or other metals simply by placing the articles in the vessel and subjecting them to the vibration of the burnishing media. Certain of the machines include fixtures which moveably support the parts to be burnished.
SUMMARY OF THE INVENTION
It is a prime object of the present invention to provide an improvement to a conventional burnishing or polishing machine which permits the utilization of the machine as an apparatus, and in a method, for polishing small flat cylindrical or circular metal articles such as coins. The machine includes a conventional drum which is mounted for vibratory movement on a table. The drum has an arcuate bottom and contains burnishing balls and a conventional comPound which may be liquid, is directed to and from the vessel in a re-circulatory cycle. Such a system is disclosed in the D. E. Roberts U.S. Patent No. 3,353,796, patented Nov. 21, 1967. In the present invention a cylindrical open end member is freely dispersed within the drum to move in response to vibration with the balls in a circulatory path which adapts that machine for the efficient and effective burnishing of relatively small flat objects such as coins. Thus the machine is particularly effective for coin polishing or the like.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of a vibratory drum mounted on a table;
FIG. 2 is a cross sectional view taken particularly along the line of 2--2 of FIG. 1;
FIG. 3 is a perspective view of an open end cylinder; and;
FIG. 4 is a cross sectional view of a modified drum arrangement including means for discharging burnishing balls from the drum.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 discloses a vibratory machine generally designated at 10 which includes a suitable table 11 having an opening 12 within which a work drum 13 is supported. The drum 13 is provided with an arcuate or semi-cylindrical wall 14 and opposite side walls 15. The walls 14 and 15 are provided with a conventional rubber-like liner designated at 16. Brackets 17 project outwardly at upper opposite ends of the drum 13 and suitable spring means 18 support the drum 13 on the table 11 to provide for vibratory movement of said drum 13. A suitable nozzle 19 is provided which will direct a liquid burnishing compound to the drum and which may be pumped therefrom in a circulatory system from an outlet fitting 20.
The drum 13 has connected thereto a frame 21 comprising vertical plates 22 which are interconnected at their lower portion by a suitable support bracket 23. An electric motor 24 is mounted on the bracket 12 and includes a drive pulley which by means of a belt 26 drives a driven pulley 27 mounted on a shaft 28 which is suitably supported on the plates 22 for rotation. One or more counterweights 29 are connected to the shaft 28 for rotation therewith and during rotation impart vibratory movement to the drum 13. The motor need not necessarily be mounted on the frame 21 but can be mounted on a suitable table frame (not shown). This type of machine is conventional as disclosed in the Ferrara U.S. Pat. No. 3,464,163 patented Sept. 2, 1969.
As best shown in FIG. 3, a cylinder 30 includes a plurality of openings 31 and the cylinder 30 is open at opposite ends. The openings 31 may be of various sizes and shapes to freely permit the burnishing media in the form of steel balls 32 and the liquid compound to flow freely therethrough during the burnishing operation. As indicated in the Figures, a charge of monetary coins 33 is placed in the drum 13 to be subjected to the burnishing or polishing operation.
In the modification shown in FIG. 4 the machine is identical to that above described. However in addition the drum 13 is provided with means permitting the burnishing balls 32 to be discharged from the drum and thereby the coins 33 are retained therein so that they can be easily removed. In this modification the drum 13 includes a plurality of openings 34 which extend throuGh the wall 14 and through the adjacent liner 16. The openings 34 are of a size so that the balls 32 can easilY pass therethrough but are small enough to prevent the smallest coin burnished from passing from the drum 13.
A cover 35 is hingedly connected as indicated at 36 to the wall 14 and the same is shown in the open position. The cover 35 includes a suitable gasket 37 which is in the closed position, shown in broken lines sealingly covers the openings 34. A latch element 38 may be rotated over the cover 35 to tightly maintain the cover in it's latched or closed position. A chute 39 is placed in position between the plates 22 for directing the discharged balls 32 into a container 40 carried on a support 41.
OPERATION
In conventional fashion the rotation of the counterweight 29 causes vibratory movement of the drum 13 and the balls 32 contained therein. Simultaneously burnishing compound is recirculated from a suitable pump and reservoir not shown from the nozzle 19 through the drain fitting 20. The counterweights 29 are so positioned to create within the drum an orbital flow of the media as indicated by the arrows.
The cylinder 30 is placed in the drum as shown in FIG. 2, with its axis extending normal to the side walls 15. A charge of coins 33 is now placed into the drum 13. During vibration the coins, balls, and cylinder move in a direction as indicated by the arrows in FIG. 1. This may be described as an orbital or circular path flow, the parts within the drum arriving at the top on the left hand side and then flowing in an arcuate path to the right downwardly to the bottom of the drum, then arcuately again to the top. At the same time the flow of the balls imparts a rOtating movement to the cylinder 30 about its own axis, and also in a smaller orbital movement to remain in a more submerged position relative to the balls and simultaneously dragging coins with the balls downwardly toward the bottom of the drum where the most effective burnishing action occurs.
The cylinder is preferrably of a suitable steel, though other metals or materials may be utilized. By dimensioning the cylinder ends approximatelY relative to the side walls 15 as shown, stability of the same is maintained against substantial variation from the transverse rotational axis diSclosed.
It has been determined that the efficiency of burnishing of the coins is greatly increased, both from a quality and time standpoint, by the utilization of the freely dispersed or floating cylinder. Some of the coins may pass thru the openings 31 and then transversely through the cylinder intermingled with the burnishing balls and thus are subjected to a slide zone action. This action is created in tumbling machines which have also been utilized for the burnishing of materials. Thus the vibratory action of the balls is supplemented by a slide zone or bumbling action of the cylinder and greatly improved results are obtained. Thus the movement of the media is thru the openings 31 normal to the cylinder axis and then along said axis outwardly from the opposite open ends of the cylinder. The apertures or openings 31 also permit the balls 33 to freely pass therethrough and yet are small enough to prevent the coins from passing. Further the cylinder prevents the coins from adhering to each other which will occur without the cylinder and thus retard proper and effective burnishing. The cylinder during rotation also is effective to prevent the balls and coins from being thrown out of the drum during heavy loading of the drum. Thus more coins can be effectively processed.
The process of burnishing thus includes the steps of vibrating the balls within the drum wherein the vibratory motion is imparted to the coins which flow in a circular, or orbital path with the balls and the cylinder. The cylinder during such vibration also is freely carried in said circular, or orbital, path and rotates about it's own axis, in it's own orbit, thereby imparting a sliding action, such as occasioned by tumbling, to the burnishing media and the coins carried therein.
The arrows in FIG. 1 describe the rotation of the mass of media, cylindrical members and the charge of materials. As indicated above, the semi-cylindrical shape of the drum and the off-center positioning of the counterweight causes this flow in what is termed as an orbit or orbital movement. This is conventional. However, in the present process a portion of the media is treated to a separate smaller diameter orbit within the freely rotating cylindrical member, which second orbit moves with the cylinder in the firSt orbit. Media and a portion of the charge is temporarily confined in this smaller orbit, subjected to the burnishing tumbling action, is discharged from the cylindrical member and additional material as portions of the mass are then so treated.
The cylindrical member is also effective, by virtue of the apertures, or openings 31, through which the balls pass to agitate the mass of media and thus increase the effectiviness of the operation without all of the coins necessarily passing through the cylinder. As indicated in the operation hereinabove the passage of the steel balls through the cylinder is believed to be the primary causative factor for the improved operation. External visual observation indicates a phenomena occurring which provides for the increased effectiveness of the burnishing balls. The eccentric vibratory or oscillating of the drum causes the balls to move in an orbital flowing pattern and in a fluid like manner, the balls entering in the apertures of the cylinder and out from the opposite ends thereof. This creates a turbulence within the mass of balls below the upper surface thereof with the balls being moved by the drum to vary the density of a plurality of the balls in various places in the drum to create a multi-convectional flow of the burnishing balls. This results in increased contact of the balls with the coins resulting in a greater polishing effect in a shorter time. This increased polishing effect is present throughout the drum because the cylinder is carried in the orbital path in the drum and is in an orbit of its own, so that the balls are carried also in an orbital path around the cylinder.
After a certain period of operation, the door 37, in the modification of FIG. 4, is opened. The recirculation of liquid compound has been stopped and the vibration is continued until the majority of the balls have been discharged through the openings 34 thru the chute 39 and the container 40. The coins remain in the drum and these may now be gathered and removed.