US 3157004 A
Description (OCR text may contain errors)
Nov. 17, 1964 ussel-100 3,157,004
TILTABLE VIBRATING BURNISHING MACHINE Filed May 18, 1960 3 Sheets-Sheet l l o I I I 1 I 1 I I 1 I I I I I n l I.
INVENTOR. ALBERT MUSSCHOOT ATTORNEYS Nov. 17, 1964 A. MUSSCHOOT TILTABLE VIBRATING BURNISHING MACHINE 3 Sheets-Sheet 2 Filed May 18, 1960 INVEN TOR. ALBERT MUSSCHOOT Wane/wits UM ATTORNEYS United States Patent TILTABIJE VIEBRATING EURNISHING MACHINE Albert Musschoot, Anchorage, Ky, assignor to Chain Belt Company, Miiwaukee, Wis a corporation of Wisconsin Filed May 18, 196i), Ser. No. 29364 13 Claims. (Cl. 51-7) This invention relates to vibratory mills and in particular to an improved structure in which the vibratory force is applied along a straight line to produce a linear vibration of the container of the mill and in which the container is carried on trunnion bearings so that it may be tilted to any position including a variety of working positions and a generally horizontal discharge position to which the vibration from the vibration exciter conveys the contents of the mill over a lip of the mill and onto a screen vibrated by the vibration exciter.
It has been found that the eificiency of tumbling mills and burnishing mills may be increased very materially by applying vibration to the container of the mill. Ordinarily this vibration is along an orbit so that the vibration produces a conveying action in the mill tending to thoroughly mix the working medium md work members as well as cause them to circulate in the mill so that all parts of each work piece is accurately processed. The burnishing mills or tumbling mills that are in use and that operate by vibration are quite small in size and there is a need for larger sized machines.
It has been found that the design used for the small machines cannot be readily applied to the larger machines. It has further been found that the orbital motion heretofore used in vibratory burnishing and tumbling mills is not suitable for all types of work and that improved results may be obtained by employing a substantially linear vibration, i.e. a vibration having components in one direction only.
The principal object of this invention is to provide a commercial size vibratory burnishing machine that may be constructed in large sizes, that is ei-licient in operation and adaptable to automatic processing systems.
Another object of the invention is to provide a vibratory burnishing machine in which the vibration generator for the burnishing machine also vibrates a screen for separating the work pieces from the work material at the close or finish of each burnishing cycle.
A still further object of the invention is to provide a self-container vibratory mill employing a direct drive tuned vibration exciter.
These and other objects and advantages are obtained in a vibratory burnishing mill constructed according to the invention.
According to the invention a generally U-shaped tub or container of a burnishing mill is mounted on trunnion bearings from a frame which in turn is resiliently mounted from a base so that the mill and frame may vibrate together. Vibratory force is applied directly to the U- shaped container by a tuned vibration exciter mounted directly on the container and arranged, when the container is in its upright position, to provide vibratory force acting along an inclined line passing through the container. When the container is tipped to its discharge position the vibratory force is again along an inclined line tending to produce conveying action along a now horizontal side of the container to discharge the material from the container.
A screen incorporated either in the frame or in the container itself is driven by the vibratory force to separate the work material from the Work pieces as they are discharged from the container.
A preferred form of the invention is illustrated in the accompanying drawings.
In the drawings:
FIG. I is a side elevation parts being shown in section and parts in outline showing the improved vibratory burnishing machine in working and discharging positions.
FIG. II is a front elevation of the machine as seen from the left in FIG. I.
FIG. III is a view of the vibration exciter as may be seen looking upwardly toward the exciter as shown in FIG. 1.
FIG. IV is a transverse section of the vibration exciter as seen from the line IV-IV of FIG. III.
FIG. V and FIG. Va are fragmentary sections taken along the line V-V of FIG. I showing the means for limiting the relative motion between the container and the frame.
FIG. V1 is a fragmentary section of the upper portion of the side walls of the container of the burnishing mill illustrating a modified form of these parts.
These specific figures and the accompanying description are intended merely to illustrate the invention and not to impose limitations on its scope.
The improved burnishing mill includes a U-shaped container or tub 10 that has trunnions 11 extending from each end of the container 10 and received in journals 12 mounted at the aplces of generally triangular end members 13 of a frame 14. The frame 14' is resiliently mounted on a plurality of springs or cushions such as air springs 15 from a base or foundation indicated by I- beams 16.
Each end of the container 10 is reinforced by a heavy channel iron 17 extending diagonally thereacross and inclined upwardly to the right as seen in FIG. I. The trunnions 11 are mounted or attached to this channel iron 17 to distribute the stress across the end of the U- shaped container 10. The upper right end of each channel iron 17 is rigidly attached to a cross plate 18 to which a vibration generator 20 is attached. The vibration generator 2t), described in detail in connection with FIGS. III and IV, is a tuned vibratory system that produces a rectilinear or straight line vibratory force acting lengthwise along the channel irons 17.
According to the invention the U-shaped burnishing mill container 10 may be rocked from its work position shown in full lines in FIG. I to a discharge position, shown in broken lines, by means of a pair of hydraulic or pneumatic cylinders 22 the lower ends of which are mounted on brackets 23 attached to the frame 14. Piston rods 24 of the cylinders 22 are pivotally connected through joints 25 to a portion of the vibration exciter adjacent themounting plate 18.
The rocking movement of the container 10 relative to the frame 14 is limited by the engagement of stop blocks 3%) that are Welded or otherwise secured in the channel irons 17 and that have shoulders 31 and 32 cooperating with pairs of stop plates 33 and 34 rigidly attached to the side members 13 of the frame 14. In the position shown in FIG. I the shoulders 32 engage the plates 33 to prevent any further clockwise motion of the container relative to the frame. When the container is moved to its discharging position the shoulders 31 engage the stop plates 34 so that the container is then arrested in a position with its side walls substantially horizontal. It may be desirable under certain circumstances that the line of action of the vibration be nearly vertical to secure particular results in the tumbling or burnishing operation. This may be accomplished by interrupting the clockwise movement as by mounting stop plates 33a on the lower sides of the side members 13 to engage the shoulders 32 when the vibration generator is nearly vertical. Intermediate working positions may be obtained by suitably positioning the stops 33 or 33a.
The hydraulic or pneumatic cylinders 22 could possibly be used to position the container relative to the frame 14 but it is preferred to use the stops and allow the cylinders to push the container rigidly against the stops for the reason that the vibration transmitted through the trunnions to the frame 14 does not not act through the center of gravity of the frame 14 and therefore there is a vibratory force exerted tending to rotate the frame with respect to the container 10. This vibratory force would produce alternating forces in the pivotal connections to the hydraulic cylinders thus causing rapid wear at these points. By allowing the cylinders to push the container against the rigid stops formed by the plates 33 and stops 33, 34, or 33a all of the, backlash is taken up and there is no possibility of chatter or looseness in the connections or alternating stresses being transmitted through the pivotal connections to the hydraulic cylinders.
The rectilinear vibration generator 20, as seen at FIGS. III and IV, comprises an outer frame 40 that is bolted or otherwise rigidly attached to the cross plate 18 at the end of the channel irons 17. The frame 40 provides parallel spaced apart surfaces 41 and 42 that are normal to the line of action of the vibration and that serve as abutting faces for a plurality of air springs 43. An exciter member 44 in the form of a box-like frame is mounted between. the air springs 43 and is guided relative to the frame 40 by a plurality of rubber hushed links 45. The excited member 44 also carries an electric motor 46 having its armature shaft 47 extended at each end of the motor to receive eccentric weights 48. As may be seen in FIG. IV intermediate crossbraces or partitions 50 of the exciter member 44 are provided with slots 51 to receive the armature shaft 47 of the motor as it is inserted into place in the exciter member 44.
The electrical connections for the motor 46 are taken out through a conduit box 52 and conduit 53 the outer end of which is guided in an air spring assembly 54 used merely as an air seal to support and guide the outer end of the conduit 53. Thus when a cover plate 55, FIG. IV, is attached to the otherwise open side of the frame 40 the mechanism can be completely closed and may actually be sealed if such is desired. The air spring assembly 54 accommodates the fully motion of the exciter member 44 relative to the frame 40. The electrical leads may then be brought out through a connector 56 and taken through a flexible connection to .a suitable source of power. This arrangement avoids the use of any flexible leads inside of the vibration generator which might lead to trouble and difliculty of maintenance. When this vibration generator 20 is mounted on the container and the motor 46 is operating at its normal speed, the air pressure in the air springs 43 is adjust ed until the vibratory system is tuned substantially to resonance. 1
This vibratory system comprises the exciter member 44 including the motor 46 as one mass, the air springs as resilient coupling members or springs and the container 10 plus the frame 14 as the other mass. Preferably the mass of the exciter member 44 including the motor 46 is approximately twenty to thirty percent of the mass of the container 10 and frame 14. When the container is in its working position, as shown in FIG. I, or inclined or rotated a small amount counterclockwise from such position and the vibration generator is operating, working media in the tub or container 10 is not only vigorously vibrated but also is conveyed in the generally circulatory motion with the material moving in a counterclockwise path as seen in FIG. I. The rate of travel in the counterclockwise path is determined largely by the angle of inclination of the vibration exciter and in particular to the horizontal component of the vibration. When the ma- 'terial has been vibrated and circulates long enough to accomplish the processing the container including the vibration exciter is titled by actuation of the hydraulic or pneumatic cylinders 22 to its discharge position,
as indicated by the broken line in FIG. I, and the vibration generator is continued in operation. In this position since the horizontal component of the vibration has been reversed, because of the change of inclination of the generator, material is conveyed from right to left on the lower side of the container 10 so that it is discharged over the lip of the side wall of the container onto a screen 60 mounted in the frame 14. The screen 6% is preferably of a mesh that permits the burnishing media to readily drop through the screen to be collected in containers therebelow and to cause the work pieces of larger size than the mesh of the screen to move to the left as seen in FIG. I. The vibration of the screen 60 results from the fact that the frame 14 is connected directly to the container 10 by way of the trunnions 11 and journals 12 so that it partakes of the vibratory motion produced by the generator 20.
One of the problems encountered in the operation of vibratory burnishing mills is that if a part being burnished rises to the top of the mixture of parts and working media adjacent a side wall of the container it may be struck by such side wall during the vibration cycleand jammed against other pieces with sufiicient force to scratch the pieces or otherwise mar their surfaces. Ordinarily this occurs only at the surface of the mixture in the container since the work pieces and work media in a mixture below the surface are well distributed and the relative motion between the work pieces and media is relatively much less than the amplitude of the vibration of the container. In order to guard against marring of the pieces from this effect an upper side wall of the container 10a is provided with an elastic lining 65 that is cushioned from the side wall of the container 18a as by means of foam rubber or similar resilient material 66 so that any parts striking such resilient surface are not sharply driven back into the mixture where they may scratch or mar other pieces. Likewise on the opposite side of the container, on the downhill side as the material is being circulated, a hinged flap 67 covered with resilient mate-- rial 63 is provided to guide the material into the circulat ing paths without allowing the pieces floating at the surface of the mixture to be struck by the side walls during the vibration cycle. Preferably the hinged flap 67 extends nearly parallel to the direction of vibration so that the parts approaching this particular surface have little or no motion or components of motion perpendicular to that surface.
FIG. VI also shows the addition of a separating screen 70 as an extension of the discharge lip of the container 16a. When the container is tipped to the discharge position as shown in the broken lines of FIG. I and the vibration generator 26 is operated the material is conveyed along the now lowermost side of the container and across the screen 70 which, partaking of the vibration of the container, provides a separation of the work pieces from the work media. It may be noted that the hinged flap 67 folds fiat against the side wall of the container during the discharge operation so that it does not interfere with the complete emptying of the container 10a.
The improved arrangement of burnishing or tumbling mill, as just described, may be readily incorporated in automatic processing equipment or processing systems because of its automatic unloading features and its ready access for loading when in its working position. By applying the vibratory force directly to the container rather than through its bearings a very vigorous vibration may be employed to secure rapid burnishing action without imposing excessive forces on the trunnions or the journal bearings carrying the trunnions. These bearings are subjected only to the forces corresponding to the weight of the frame 14 and the acceleration of the container 10. Since the frame 14 may be only a fraction of the weight of the container this means that the forces are correspondingly minimized.
Various modifications in the structure and arrangement of the parts may be made without departing from the spirit and scope of the invention.
Having described the invention, I claim:
1. A vibratory burnishing machine, comprising in combination, a frame, resilient means supporting the frame, a container that is pivotally mounted on the frame for movement from an upright position to at least a horizontal position, a rectilinear vibration generator rigidly mounted on the container, said generator being adapted to apply vibratory force to the container along a substantially straight line inclined to the horizontal when the container is in either its upright or horizontal positions, and means for moving the container from one position to the other.
2. A vibratory burnishing machine, comprising in combination, a frame, resilient means supporting the frame, a container mounted on the frame, and a rectilinear vibration generator mounted on the container, said generator including a tuned vibratory system having a mass vibrating along a straight path inclined to the side of the container whereby said container is vibrated along a straight path inclined to its side walls.
3. A vibratory burnishing machine, comprising in combination, a container having generally straight side walls, resilient means supporting the container, means for moving said container from a substantially upright position to a substantially horizontal position, and a rectilinear vibration generator rigidly attached to the container, said generator including a substantial mass that moves along a substantially straight line, said generator being oriented on the container to vibrate the container along a straight inclined path that conveys material from the container when the container is in its substantially horizontal position.
4. A vibratory burnishing machine, comprising in combination, a container having generally straight side walls, resilient means supporting the container, means for moving said container from a substantially upright working position to a substantially horizontal position, a rectilinear vibration generator including a tuned vibratory system comprising a mass resiliently coupled to the container and vibrating along a generally straight path, said generator being rigidly attached to the container with said path inclined to one side of the vertical when the container is upright and inclined to the other side of the vertical when the container is horizontal.
5. A vibratory burnishing machine, comprising in combination, a container having generally straight side walls, a sifting screen mounted in the upper portion of one side wall, resilient means supporting the container, means for moving the container from a substantially upright position to a substantially horizontal position with said one side wall lowermost, a rectilinear vibration generator rigidly attached to the container to vibrate the container along a generally straight path that inclines upwardly away from the bottom of the container when the container occupies its horizontal position to convey material across the screen and that inclines upwardly away from said screen to circulate material in the container when in its upright position.
6. A vibratory burnishing machine, comprising in combination, a container, a frame, resilient means supporting the frame, said container being pivotally mounted in the frame, means for moving the container from a generally upright position to an unloading position, a rectilinear vibration generator mounted on the container, a screen mounted on the frame in position to receive material discharged from the container, said vibration generator being arranged when the container is in unloading position to transmit vibration along an inclined path to said frame whereby materials are conveyed across said screen.
7. A vibratory burnishing machine, comprising in combination, a frame, resilient means supporting the frame, a container that is U-shaped in cross section pivotally 3 mounted in the frame, means for moving the container from a generally upright position to a generally horizontal position, means for limiting the movement of the con tainer at intermediate positions and cooperating with the moving means for effectively locking the container to the frame at such positions, a screen mounted on the frame in position to receive material discharged from the container, a rectilinear vibration generator mounted on the container and oriented to vibrate the container and frame along an inclined path that conveys material across the screen when the container is in its generally horizontal position and that circulates material in the container when the container is upright.
8. A vibratory burnishing machine, comprising in combination, a frame, resilient means supporting the frame, a container that is generally U-shaped in cross section pivotally mounted on the frame, said container being movable from a generally upright position to a generally horizontal position, means acting between. the container and frame for selectively positioning the container with respect to the frame, a rectilinear vibration generator attached to the container, said generator including a vibratory system for producing substantially straight line vibratory motion of the container and frame along a vertical path when the container is positioned intermediate the ends of its range of travel relative to the frame.
9. In a vibratory burnishing machine, according to claim 8, a screen mounted in said frame in position to receive material discharged from the container, the vibration of the container and frame when the container is in discharging position serving to convey material across the screen.
10. A vibratory burnishing machine, comprising in combination, a frame including spaced apart upstanding side members, resilient means supporting the frame a container that is generally U-shaped in end elevation, a pair of parallel drive members extending diagonally across the ends of the container, a tuned rectilinear vibration generator mounted on said parallel drive members for transmitting linear vibration force along said members, a pair of trunnions extending axially from the con tainer generally in line with the combined center of gravity of the container and vibration generator, journals in the side members of the frames that receive the trunnions, means for rocking the container and vibration generator assembly on the trunnions and for locking the assembly with respect to the frame at selected positions, and a screen mounted in the frame to receive material discharged from the container, said vibration generator serving to transmit vibrational force through the frame to vibrate the screen to convey material thereacross.
11. In a vibratory burnishing machine, in combination, a container comprising side and end walls and a bottom, a rectilinear vibration generator rigidly connected to the container and extending from the container along a line inclined to the side walls of the container, and a resilient pad on at least one side wall of the container at the working level of burnishing media in the container.
12. In a vibratory burnishing machine, in combination, a container comprising side and end walls and a bottom, a rectilinear vibration generator rigidly connected to the container and extending from the container along a line inclined to the side walls of the container for vibrating the container along such lines, and a flap attached to one side wall and extending toward the other along a line generally parallel to said line at the surface of the work ing media in the container.
13. In a tiltable vibratory burnishing machine, in combination, a container comprising side walls and a bottom, a rectilinear vibration generator rigidly connected to the container and extending from the container along a line inclined to the side walls of the container, said container being tiltable from a vertical to at least a horizontal position, a flap hingedly connected to that 3 side wall toward which the container is tiltable, said flap being covered with resilient material and arranged to lie fiat against the side wall when the container is tilted and to lie generally parallel to the line of action of the vibration generator at the surface of theworking 5 media when the container is upright.
References Cited in the file of this patent UNITED STATES PATENTS 526,389 Gerhardt et a1. Sept. 25, 1894 10 8 Strang Sept. 29, 1942 Cottrell Feb. 18, 1947 Bodine Feb. 8, 1949 Brandt Mar. 7, 1961 Brevik Aug. 1, 1961 Brandt Aug. 29, 1961 Carrier Dec. 5, 1961 FOREIGN PATENTS Germany Oct. 20, 1955