Vibratory finishing machine

A vibratory finishing machine comprising a tub-like container having a substantially open upper side and defining a peripheral rim portion, the container adapted to receive workpieces and finishing media, means for imparting vibratory movement to the container and thereby causing the media to perform a finishing operation on the workpieces, a support structure for the container and including a base adapted to rest upon a support surface, the support structure also including a bin support section projecting upwardly from the base to a position subjacent the rim portion of the container, spring connected between the uppermost part of the support section and the container rim for resiliently supporting the container thereon, a vibratory mechanism including an eccentrically weighted vibratory shaft arranged substantially parallel to the longitudinal axis of the container at a position located below the container and offset asymmetrically from the center of the container.

BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention is generally directed toward vibratory finishing 
machines and more particularly, toward a new and improved finishing 
machine of the type adapted to be used with steel finishing media. 
One of the objectionable characteristics of utilizing steel finishing media 
in vibratory finishing machines is the difficulty in obtaining the desired 
"flow" of the media. One of the significant reasons for such difficulty 
resides in the need for utilizing certain chemical compound additives in 
the finishing operation which have been found to severely hinder or 
preclude media flow, which in turn results in precluding effective 
workpiece finishing. Although satisfactory media flow has been obtainable 
in the past through the use of large counterweights, such an approach has 
not been feasible with steel media because of the high magnitude of 
media-workpiece impact which prevents obtaining the fine finish desired 
for the type of parts that are traditionally processed with steel 
finishing media. 
The present invention provides a new and improved vibratory finishing 
machine which has been found to provide highly improved media flow at low 
magnitudes of media-workpiece impact, thereby obviating the various 
objectionable characteristics of the prior art machines. The finishing 
machine of the present invention utilizes a unique combination of 
features, including the provision of support springs for the finishing tub 
at a position adjacent the peripheral rim or edge of the tub, the use of 
an asymmetrically located weighted vibratory shaft and the additional use 
of an asymmetrically located tub weight that is preferably located on the 
opposite side of the longitudinal axis of the tub from the vibratory 
shaft, as will hereinafter be described in detail. 
It is accordingly a general object of the present invention to provide a 
new and improved vibratory finishing machine. 
It is a more particular object of the present invention to provide a new 
and improved vibratory finishing machine that is particularly, although 
not necessarily, adapted for use with steel finishing media and is 
intended to provide improved finishing action, as compared to prior known 
finishing machines. 
It is another object of the present invention to provide a new and improved 
finishing machine of the above described type which incorporates a 
plurality of suspension or support springs that are located above the 
center of gravity of the finishing tub, and specifically are located 
directly beneath the peripheral flange or rim of the tub. 
It is still another object of the present invention to provide a new and 
improved finishing machine that is provided with an asymmetrically located 
weighted vibratory shaft. 
It is a further object of the present invention to provide a new and 
improved vibratory finishing machine that may be provided with an 
asymmetrically located tub weight which is preferably located on the 
laterally opposite side of the longitudinal tub axis from the weighted 
vibratory shaft. 
It is still a further object of the present invention to provide a new and 
improved vibratory finishing machine wherein improved media flow is 
achieved in the range of low media impact with the media workpieces, 
whereby to improve the operational performance of the machine of the 
present invention. 
Other objects and advantages of the present invention will become apparent 
from the following detailed description taken in conjunction with the 
accompanying drawings.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now in detail to the drawings and in particular to FIG. 1 
thereof, a vibratory finishing machine 10, in accordance with one 
preferred embodiment of the present invention, is shown as comprising a 
tub-like container 12 that defines an open upper sided finishing chamber C 
adapted to receive a quantity charge of finishing media and a plurality of 
workpieces upon which a finishing operation is to be performed. The 
container 12 is operatively mounted upon a support structure, generally 
designated by the numeral 14, which is provided with drive means in the 
form of a motor 16 that is drivingly connected to an eccentrically 
weighted shaft 18, rotation of which shaft 18 imparts vibratory movement 
to the container 12 so that the aforementioned finishing operation may 
occur. 
As best seen in FIG. 3, the container 12 comprises laterally spaced 
parallel, generally vertically disposed side sections 20 and 22 between 
which longitudinally spaced, vertically extending end sections 24 and 26 
are located. The lower end of the container 12 is closed by a generally 
arcuate-shaped bottom section 28, with the top or upper end of the 
container 12 being open so as to provide an access opening 30 for 
receiving the aforementioned finishing media and workpieces. Typically, 
the container 12 would be provided with an interior liner 31, fabricated, 
for example, of a material such as disclosed in U.S. Pat. No. 3,707,058. 
The upper end of the container 12 includes a peripheral rim portion 32 
which is formed with a pair of longitudinally extending laterally 
outwardly projecting flanges 34 and 36 which are affixed to the upper 
terminal edges of the tub side sections 20 and 22. The end section 26 of 
the container 12 is provided with a discharge chute 38 having a closure 
door 40 which may be selectively moved to an open position to permit 
discharge of the finishing media and workpieces upon completion of a 
finishing cycle. Typically, the closure door 40 would be provided with 
suitable locking or latching means 42 in a manner well known in the art. 
The support structure 14 includes a generally horizontally disposed base 
section 46 having lower support legs 48 adapted to rest or bear upon a 
suitable support surface 49, as seen in FIG. 1. The base section 46 
includes a longitudinally outwardly extending end section 50 upon which 
the aforementioned drive means 16 is secured, for example, by suitable 
screws, bolts or the like 52. Located directly above the drive means or 
motor 16 are conventional operating controls, generally designated by the 
numeral 54, by which the operational timing cycle may be controlled, as 
well as the magnitude of the vibrational movement of the container 12, in 
a manner well known in the art. 
In accordance with some of the principles of the present invention, the 
support structure 14 includes a plurality of four vertically disposed 
support columns, generally designated 56, which are arranged two on each 
side of the container 12, as best seen in FIGS. 1 and 4. The support 
columns 16 on each side of the container 12 are generally longitudinally 
aligned with one another, and the pairs of columns 56 at the opposite 
longitudinal ends of the container 12 are generally laterally aligned with 
one another. The lower ends of the columns 56 are provided with mounting 
flanges 58 which are adapted to be secured by suitable screws, bolts, 
welding, etc., 60 to the base section 46, whereby to rigidly secure the 
columns 56 to the support structure 14. As best seen in FIG. 5, the upper 
end of each of the support columns 56 is provided with an upper end member 
62 upon which is mounted a lower spring seat 64. The spring seats 64 may 
be fabricated of an elastomeric material and be secured to the upper end 
members 62 by suitable bolts 66 that extend downwardly through the seats 
64 and are threadably received within central threaded openings 68 of the 
members 62. The spring seats 64 serve to operatively support the lower 
ends of a plurality of helical coil springs 70 which extend vertically 
upwardly from the seats 64 to a position directly below the flanges 34, 
36. The upper ends of the springs 70 are engaged with suitable upper 
spring seats 72 which are secured to the underside of the flanges 34, 36 
by suitable screws, bolts or the like 74. 
In accordance with another feature of the present invention, the 
eccentrically weighted shaft 18 is provided with a plurality of eccentric 
weights, generally designated by the numeral 76, and which, when rotated 
via a drive shaft 78 connecting the shaft 18 with the drive means 16 and 
suitable couplings 80, 82, serves to impart vibratory movement to the 
container 12 and hence to the finishing media and workpieces contained 
within the chamber C thereof. Suitable connecting means or structure, as 
designated at 84 in FIG. 4, operatively connects the shaft 18 to the 
underside of the container 12, in a manner well known in the art. As best 
seen in FIG. 4, the longitudinal axis of the shaft 18 is offset laterally 
a distance D from the longitudinal center line of the container 12. The 
magnitude of the offset distance D may be varied in accordance with the 
desired vibratory dynamics and one satisfactory magnitude of the offset D 
has been found to be equal to approximately one-half the lateral distance 
between the axis of the opposed pairs of coil springs 70. Of course, 
various other offset distances are intended to come within the scope of 
the present invention. 
In accordance with another feature of the present invention, the flange 36 
is provided with counterweight means which is representatively designated 
by the numeral 86. The weight 86 is preferably substantially co-extensive 
of the longitudinal length of the container 12 and is secured to the upper 
side of the flange 36, for example, by the aforementioned screws, bolts 74 
that are utilized to connect the upper spring seats 72 to the flange 36. 
The cross-sectional shape of the counterweight 86 may be variable, 
although in a preferred construction of the present invention, the 
counterweight is of uniform cross-sectional shape along its entire length 
and is located on the flange of the container 12 that is disposed on the 
opposite side of the longitudinal center line of the container 12 from the 
shaft 18. In other words, in a preferred construction of the present 
invention, the shaft 18 is offset laterally in one direction from the 
longitudinal center line of the container 12, while the counterweight 86 
is located on the container flange disposed on the opposite side of said 
center line. 
The aforegoing combination of elements pursuant to the present invention, 
provides a vibratory finishing machine which exhibits highly improved 
media flow, particularly at low magnitudes of media-workpiece impact, 
whereby to particularly adapt the present invention for use with steel 
media without the requirement of large amounts of chemical compound 
additives that have been necessitated in the past. Of course, the present 
invention will find wide and varied use and the various alternative types 
of media of the present invention is not intended to be solely limited in 
its application to steel finishing media. By virtue of the fact that the 
vibratory finishing machine of the present invention is of a relatively 
straightforward design which incorporates a number of components of 
similar type finishing machines already in existence, the improved 
features of the present invention may be obtained without incurring 
significant additional tooling expenses. Additionally, by virtue of the 
fact that the counterweight 86 may be varied in size in accordance with 
the desired media flow dynamics, the present invention will find 
universality of application. 
While it will be apparent that the preferred embodiment of the invention 
disclosed is well calculated to fulfill the objects above stated, it will 
be appreciated that the invention is susceptible to modification, 
variation and change without departing from the proper scope or fair 
meaning of the subjoined claims.