Aug. 22, 1967 R. w. MOORE VIBRATORY FINISHING Filed July 2, 1964 www www, www
www www @my A@ M www 4/ N www E@ ph 'f1/.Moore BMMW/ ATTCRNEYS United States Patent O 3,336,701 VIBRATORY FlNlSI-HNG Ralph W. Moore, Hagerstown, Md., assignor to The Pangborn Corporation, Hagerstown, Md., a corporation of Delaware Filed July 2, 1964, Ser. No. 379,814 7 Claims. (Cl. 51-7) This invention relates to vibratory finishing, more particularly the type of vibratory or gyratory finishing suitable for treatment of Work pieces of metal or the like for the purpose of deburring, descaling, cleaning, polishing, burnishing, rounding corners and edges, etc.
The use of vibration or gyration for the above purpose has been known for some time. However, machines built for these purposes have been relatively complicated and cumbersome as well as somewhat awkard to use when adapted for variable loading.
Among the objects of the present invention is the provision of novel equipment land techniques for the above type of finishing that simplifies the handling of widely varying loads and reduces the cost of such treatment.
The above as well as additional objects of the present invention will be more clearly understood from the following description of several of its exemplications, reference being made to the accompanying drawings wherein:
FiG. l is a front elevation with a portion broken away of a representataive of the present invention; and
FIGS. 2-3 are fragmental views of modified apparatus representative of the present invention.
According to the present invention the vibratory finishing apparatus has a container for the work articles, and vibrating structure connected to gyrate the container. The container is supported by air cushions as in the Iabove-identified parent applications. These air cushions are preferably arranged effectively below the container, preferably with four or more such cushions in symmetrically spaced relationship although fewer can be used if desired. It is found particularly helpful, however, to have at each supported location an air cushion effectively below the container and at least one pre-loading device such as another air cushion or spring effec- A tively above the container, since `this is found to provide better control over the operation of the apparatus and to increase its loading range. A cushion is effectively below the container when the container or a supporting member secured .to the container rests on top of the cushion. Conversely ya cushion or spring is effectively above the container when the container or a supporting member secured to the container depends from the cush- 1on.
The vibrating movement of the container is advantageously utilized in such a manner to produce continuous flow through the container. This continuous flow results by providing a greater amplitude of viibration at the discharge end of the container than lat the container inlet so that the contents move toward the discharge end. The difference in amplitude of vibration can be effected in a number of advantageous ways. For example, an eccentric weight can be mounted on the vibrating inducing shaft under the container with `the shaft slightly skewed with respect `to the longitudinal axis 0f the container. In another particularly advantageous form of this invention a pair of shafts are mounted under the container with different eccentric weights on each shaft. These shafts may be driven by a single motor, or each shaft may be individually driven.
FIG. 1 illustrates an embodiment of the present invention as applied to machines for subjecting a stream of work articles to vibratory treatment on a continuous basis.
Here there is provided a work container 210 of generally elongated shape and suspended on air cushions 242, 243 which in turn rest on fixed piers 254, 255. Vibration is supplied by an electric motor 268 having a shaft 218 projecting in opposite directions and held in bearings 222 secured to the container by means of transverse plates 224 depending from the bottom of the container and reinforced with side plates 226. Eccentric weights 220 fastened to the ends of the shaft 218- are orientated so that they have identical eccentricity.
Under the discharge end 211 `of container 210 is a second electric motor 269 having a second shaft 271 axially aligned with shaft 218 and projecting in opposite directions from motor 269. Shaft 271 is held in bearings 273 secured to container 210 by transverse plates 275. Eccentric weights 277 are fastened to the ends of shaft 271 and are so oriented that they are of different eccentricity than weights 220, These weights 277 are arranged to produce a greater amplitude of vibration at discharge end 211 than at front or receiving end 209. As a result, the contents How smoothly through container 210 without the necessity of elevating end 209 although the container 210 may be inclined as illustrated in FIG. 1.
For continuous operation there is provided a loading device such as the chute 213 which delivers the work articles to the front end 209 of the container. At the same time an unloading device is provided at the rear end 211 of the container and in the construction of FIG. 1 is shown in the form of a lip 215 under the outer edge of which is positioned a pair of screens 227 and 229. Screen 227 is directly below lip 215 and is inclined in a direction that feeds to a removal conveyor 231 objects such as work articles which drop on the screen and are too large to fall through between the screens openings. Screen 229 is directly below screen 227 and is inclined laterally toward a recycling conveyor 233 where it guides objects such las abrasive vibration media, which drop through screen 227 land are too large to fall through the openings of screen 229. Under screen 229 can be placed a receiver 235 for fine particles such as fragments of vibration media, scale and burrs removed from the work articles, etc., as they fall through the openings of screen 229.
Recycling conveyor 233 receives the vibration media and returns them to the feed end of the container 210. It is shown as mounted on a set of three rollers 237, 239, 241. Rollers 237 and 239 are at the ends of the recycling conveyor and are tilted with respect to each other, Whereas roller 241 is a guide roller near the upper end of the conveyor positioned parallel to roller 237. Rollers 237 and 241 are in horizontal position whereas roller 239 has its end near the container tilted downwardly so as to cause the upper flight of the -conveyor to incline after it passes guide roller 241. Alongside this tilted portion `of the conveyor the container 2li) has a lip 261 that projects out under the adjacent edge of the tilted conveyor portion.
The recycling conveyor 233 collects the vibration media and raises it up to the level of the guide roller 241 after which its tilted portion causes the raised media to fall into the container. To assure that the media falling onto the conveyor at its lower end does not fall off, a fixed three-sided retainer box 263 can be provided so as to rest lightly against the portion of the upper conveyor flight underneath screen 229. Also to assure that the recycling media all return to the container, a fixed deflecting bar 265 can be rested lightly against the tilted portion of the conveyor.
In operation the construction of FIG. 1 can first have its container supplied with a liquid to be used in the desired vibration treatment and can also be loaded with the abrasive media. The work articles can be fed to it, the vibration started, and the eccentricity adjusted so that the work articles take the desired time in transversing the container and then appearing on the unloading screen 227. Once set in this operation, it can be so maintained indefinitely so long as the work-article feed is continued. For prolonged operations, the liquid in the container may have to be replenished and this can be done either on a batch basis or on a continuous basis. Siphons not shown are conveniently used to remove the old liquid while fresh liquid is added gradually so as to effect the change-over. If desired, the fresh liquid can be added at the feed end, and overflow of liquid at the discharge end can then merely be discarded. The abrasive media can also be treated if desired, as by washing, during their recycling travel on conveyor 233. When the continuous treatment draws to a close and the feed of Work articles is terminated, the vibration treatment is continued with the abrasive media recycled until all the work articles are unloaded by entrainment with the media. The abrasive media can then be unloaded, if desired, as by shoveling it out of the container, or the container can be made to tilt so as to dump its contents or to increase the longitudinal inclination to such a degree that continued vibration will completely or substantially empty it. Alternatively the container may have a wall or panel at the discharge end 211 made removable so that upon removal its contents will be more readily discharged.
Flow through container 210 is particularly effective when, for example, the difference in Weight between weights 277 on shaft 271 and weights 220 on shaft 218 is for example pounds, such as weight 277 being 2O pounds and Weight 220 being l5 pounds. The difference in amplitude of vibration between ends 209 and 211 of container 210 can also be aided by having one end, such as receiving end 209, made heavier than the other end.
Other modifications of the invention can be made, as for example the pair of shafts 218 and 271 under container 500 and driven by known motor drives.
Additionally, shafts 218 and 271 can be operated by a single motor or can be positioned parallel to each other across the longitudinal axis of the container as shown in FIGS. 2-3, respectively.
The continuous flow produced by the above described arrangements is particularly effective for large production in which pieces are continuously fed from loading chute 213 into receiving end 209 of container 210. Eccentric carrying shafts 218 and 271 effectively move the workpieces smoothly through container 210 while the workpieces are being cleaned or descaled, etc. and continuously discharges the finished workpieces from end 211 of container 210.
Obviously, many modifications and variations of the present invention are possible in the light of the above teachings, lt is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. An apparatus for subjecting work articles to vibratory finishing treatment comprising a container for said work articles, said container being elongated and having a longitudinal axis, said container having an inlet end and an opposite outlet end, said container being inclined toward said outlet end, resilient mounting means for said container, vibrating means connected t0 said container for imparting a greater amplitude of vibration to said outlet end of said container than to said inlet end whereby th work articles are simultaneously treated and continuously flow through said container toward said outlet end having said greater amplitude of vibration, said vibrating means including a pair of shafts mounted under said container with eccentric weights being on said shafts, said eccentric weights at said outlet end being of greater mass than said weights at said inlet end, and said shafts being co-planar in a plane parallel to said longitudinal axis of said container.
2. The apparatus of claim 1 wherein said shafts are parallel to each other and disposed across the longitudinal axis of said container.
3. The apparatus of claim 1 wherein said shafts are aligned with each other and disposed parallel to the longitudinal axis of said container.
4. The apparatus of claim 3 wherein a single motorized drive means is operably connected to both of said shafts.
5. The apparatus of claim 3 wherein automatic feed means is connected to the inlet end of said container, and automatic unloading means being connected to the outlet end of said container.
6. The apparatus of claim 3 wherein one of said inlet end and of said outlet end of said container is heavier than the other of said inlet end and of said outlet end.
7. The apparatus of claim 6 wherein said heavier end of said container is the inlet end.
References Cited UNITED STATES PATENTS 1,590,339 6/1929 Wood.
1,858,328 5/1932 Heymann 198-220 1,908,104 5/1933 Bell 51-163 2,200,724 5/ 1940 Robins 517 2,968,424 1/1961 Lawson 198-220 3,148,483 9/1964 Fossen 51-7 HAROLD D. WHITEHEAD, Primary Examiner.