Patent Publication Number: US-6702657-B2

Title: Continuous polisher machine

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to machines for polishing the surface or surfaces of workpieces, such as for example workpieces made of glass, ceramic, silicon crystals and metals. Even more particularly this invention relates to an improved such polishing machine which eliminates the need for employing a plurality of different drive motors to effect various operations of the polisher. 
     There are currently available in the marketplace a number of machines for polishing products such as those made from glass, ceramic, silicon crystals and metals. U.S. Pat. No. 4,916,868, for example discloses a honing, lapping or polishing machine which utilizes three disc-shaped work holders each having therein a series of circular apertures for holding workpieces, and with the discs being mounted for rotation about their respective axes and also for revolution within a surrounding, circular gear type member. One disadvantage of this mechanism is that it requires a plurality of separate electric motors for driving various parts on the machine. U.S. Pat. No. 6,045,716 also discloses a plurality of carrier devices for holding workpieces, and which carrier devices are operated independently of each other. This is typical in most prior polishing machines in which the various work carriers are driven by a plurality of independently operated DC motors. 
     It is an object of this invention, therefore, to provide for a polishing machine improved drive means which utilizes a single electric motor for simultaneously rotating a polishing table, and a plurality of removable workpiece holders mounted on a polishing surface of the table for rotation therewith and for rotation relative thereto. 
     Another object of this invention is to provide improved drive means of the type described which rotates workpiece holders and the polishing table in the same direction about their axes. 
     A still further object of this invention is to provide for a machine of the type described improved, circular workpiece holders retained for rotation about stationary vertical axes during rotation of the table upon which they are mounted. 
     Other objects of the invention will be apparent from the specification and from the recital of the appended claims particularly when read in conjunction with the accompanying drawings. 
     SUMMARY OF THE INVENTION 
     A disc-shaped polishing table, which is mounted on a machine frame for rotation by an AC electric motor coaxially about a vertical axis, has thereon an upper, generally planar polishing surface for supporting for rotation thereon a plurality of circular workpiece carriers. A plurality of rigid arms are supported on the frame above the table to extend radially inwardly thereof in angularly spaced relation to each other, and in vertically spaced relation to the polishing surface. A pair of rollers are supported on each of the arms for rotation therebeneath about spaced, vertical axes, and for rolling engagement with the outer peripheral surface of one of said carriers at angularly spaced points thereabout. One roller of each pair thereof is operatively connected to the table to be rotated thereby, and is in rolling, driving engagement with one of said carriers to effect rotation thereof while the other roller of the pair is rotated by the carrier with which it is engaged. Also, each of the carriers is annular in configuration and has a disc-shaped workpiece holder removably mounted coaxially therein to be seated on the polishing surface, and each holder has therethrough spaced openings for accommodating the ends of the workpieces that are to be polished. 
    
    
     THE DRAWINGS 
     FIG. 1 is a perspective view of a continuous polisher machine made according to one embodiment of this invention; 
     FIG. 2 is a perspective view similar to FIG. 1, but with several of the covers shown in FIG. 1 removed to illustrate in greater detail the three drive mechanisms which are employed for driving workpiece carrier rings as noted hereinafter; 
     FIG. 3 is a plan view of the machine as shown in FIG. 1, illustrating the carrier rings which are employed in the three work stations on the machine; 
     FIG. 4 is an elevational view of one side of the machine with portions of the upper half of the view shown in section to illustrate in greater detail the drive mechanism for the carrier rings; 
     FIG. 5 is a detail plan view of one type of workpiece carrier ring employed with this invention; and 
     FIG. 6 is a sectional view taken generally along the line  6 — 6  in FIG.  5  and looking in the direction of the arrows. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings by numerals of reference and initially to FIGS. 2,  3  and  4 ,  10  denotes generally a rectangular frame or base made of metal, or the like, and having on each of its four corners vertical leg sections  11  equal in length and interconnected by horizontally disposed beams  12 . Fixed to the upper ends of the legs  11  of the base  10  is a rigid, rectangularly shaped top plate  14 . Secured at the bottom thereof on plate  14  centrally thereof is a circular recovery tank, which is annular in cross section, as shown in FIG. 4, and which has an outside diameter slightly larger than the width of the top plate  14 . Secured centrally on the upper surface of top plate  14 , and disposed in radially spaced, coaxial relation to the inside diameter of the annular tank  15  is a circular bearing assembly  16  (FIG.  4 ). Supported on its lower end on the circular bearing assembly  16  for rotation coaxially thereof is a large, heavy, generally disc-shaped granite or cast iron table  17 , which has a diameter slightly less than the outside diameter of tank  15 , and which has thereon a plane, flat upper surface covered with a material or fluid for polishing as noted hereinafter. 
     Referring now to FIG. 4, supported by the cross beams  12  adjacent one side of frame  10  is an AC electric motor  21  having an output shaft (not illustrated) drivingly connected to a single speed reducer  22  of conventional design, such as offered for sale by Boston Gear. The output shaft of reducer  22  is connected to a pulley  23 , which in turn is connected by a V-belt  24  to another pulley  25  that is secured to the lower end of a shaft  26  which is mounted in frame  10  for rotation coaxially of table  17 . Shaft  26  is drivingly connected to the lower end of a spindle assembly drive shaft  27 , the upper end of which extends through a registering opening in plate  14 , and part way into a central opening in table  17 . Intermediate its ends the spindle drive shaft  27  has integral therewith and coaxially thereof, an enlarged-diameter spindle plate  28 , which extends through a registering opening in the top plate  14 , and is bolted or otherwise secured against the underside of table  17  coaxially thereof, so that any rotation imparted to the shaft  26  is also imparted to table  17 . 
     The upper end of the spindle assembly drive shaft  27 , which projects into the central opening in the table  17 , is drivingly connected coaxially to the lower end of a reduced-diameter sun gear shaft  30  which, as shown in FIG. 4, extends vertically above the upper surface of table  17  and coaxially through a coupling member  31 . Secured coaxially to shaft  30  adjacent the upper end thereof is a large spur gear  32 , which functions as a sun gear for driving a plurality of smaller spur gears as noted in greater detail hereinafter. 
     Secured at their lower ends to the upper surface of table  17  adjacent each of its four corners, and projecting vertically upwardly equidistantly above the upper surface of table  17  are four, cylindrically shaped pillar assemblies  34 . Secured to the upper end of each pillar assembly  34  is the slightly offset end of one of four, similar, rigid arms, three of which are denoted by numerals  35  and one by numeral  36 . The opposite ends of arms  35  and  36  project horizontally and radially inwardly over the face of plate  17  and part way toward the center thereof at approximately 90° intervals about its centerline. At their inner ends the arms  35  and  36  are secured to the underside of a circular sun plate  37  having therethrough a central, circular opening in which are secured a pair of flanged, annular bearings  38  through the centers of which the sun gear shaft  30  extends rotatably and coaxially. Each of three, identical gear shafts  40  is rotatably mounted adjacent one end thereof in a circular opening formed adjacent the inner end of each of the three arms  35  by a pair of circular bearings  41  (FIGS. 2 and 4) secured to the upper and lower surfaces, respectively, of a respective arm  35 . Each shaft  40  projects vertically above its bearings  41  in radially spaced parallel relation to shaft  30 , and has secured to its upper end a small spur gear  42 . The teeth of the spur gears  42  are in driving, meshing engagement with the teeth of the sun gear  32 . 
     Intermediate its ends each of the three arms  35  has secured to opposite sides thereof, and in coaxial registry with each other, a pair of circular bearing blocks  44  and  45 , the axial bores of which register coaxially with a circular opening in the respective arm  35 . Rotatably mounted in the registering bores of each pair of bearing blocks  44  and  45 , and extending rotatably through the registering opening in the associated arm  35  is a drive roller shaft  46 , which projects coaxially beyond opposite ends of the associated pair of bearings  44  and  45 . Secured to the lower end of each shaft  46  is a drive roller  47  which is employed, as noted hereinafter, for driving a workpiece carrier ring. A pulley which is fixed to the upper end of each shaft  46  is connected by a timing belt  48  to a like pulley which is secured to the upper end of the associated gear shaft  40  that is rotatably mounted in the inner end of the associated arm  35 . In this manner, when motor  21  drives shafts  26  and  30  and hence gear  32  in, for example, a counterclockwise direction as shown in FIG. 3, then the spur gears  42  drive shafts  40 , and hence belts  48 , shafts  46  and rollers  47  thereon in a clockwise direction. Moreover, all shafts  46  and their drive rollers  47  are thus rotated at the same speed. 
     Each of four rather small, rigid, straight arms  51  is pivotally connected at one end thereof to the lower end of one of four bolts  52 , each of which is secured adjacent its upper end in one of the arms  35  and  36  adjacent its slightly offset outer end. Rotatably mounted on the opposite end of each arm  51  for rotation slightly therebeneath about an axis that extends parallel to the axis in a rotation of table  17 , is a nylon guide roller  54 . Intermediate its ends each arm  51  is pivotally coupled to a threaded scissor rod  55  intermediate the ends thereof. Each rod  55  adjustably threads at its inner end into an internally threaded rod coupling  56  (FIGS.  1  and  3 ), which is pivotally connected at its inner end to the associated arm  35 ,  36 , and which in the case of the arms  35  has secured to its outer end a circular, palm grip head  57  for manually rotating the associated rod  55  selectively in opposite directions. Rods  55  associated with the arms  35  normally prevent any pivotal movement of the arms  51  to which they are connected, but can be manually rotated to cause the associated arms  51  to adjust their respective guide rollers  54  inwardly or outwardly relative to the outer peripheral surface of the table  17 . 
     Referring now to FIGS. 5 and 6,  60  denotes generally one type of workpiece carrier ring which is adapted to be employed with the polishing machine disclosed herein. Each ring  60  comprises an outer, metallic ring  61  having an integral, generally rectangularly-shaped key  62  protecting radially inwardly from its inner peripheral surface adjacent one end thereof. Removably mounted coaxially in one end of the ring  61 , the lower end as shown in FIG. 6, is a circular, generally disc-shaped layer  63  of plastic material, such as Lexan, which has in its outer peripheral surface a rectangularly-shaped notch for accommodating the key  62  on the ring  61 . Layer  63  has therethrough a plurality of spaced openings  64 , which in the embodiment illustrated in FIG. 6 happen to be illustrated in rectangular configurations, but as shown in FIG. 3 can be of any desired shape which would be suitable for accommodating the workpieces that are to be polished. 
     In use, as shown for example in FIG. 3, three of the carrier rings  60  are placed upon the table  17  with the outer, metal ring  16  of each carrier ring having its outer peripheral surface engaged both with the drive roller  47  that rotates beneath one of the arms  35 , and also, at another point on its peripheral surface with the nylon guide roller  54  carried by the arm  51  which is pivotally mounted at its opposite end to the associated arm  35 . Thus, when the electric motor  21  drives the sun gear  32  in a counterclockwise direction, as illustrated in FIG. 3, the drive rollers  47  rotate the three carrier rings  60  that are engaged therewith also in a counterclockwise direction about stationary vertical axes, so that as the surface of the table  17  rotates beneath the carriers  60  the metal rings  61  and hence the plastic layers  63  that are drivingly connected to the rings  61  by the keys  62 , are likewise rotated by the associated surrounding ring  61 , and at the same rpm. Although not shown specifically in FIG. 3, the apertures in the disc-shaped layers  63  are disposed to have releasably disposed therein the correspondingly-shaped ends of glass items or the like, the bottom surfaces of which are engaged directly with the polishing material disposed on the upper surface of the table  17 . Therefore the plane bottom surfaces of such workpieces (not illustrated) would be exposed to the polishing materials on the face of the table  17 , and also would be rotated relative to the table  17  as its rotates beneath the carrier rings  60 . The motion of table  17  tends to urge each of the carrier rings  60  into engagement with the rollers  47  and  54  that are supported by the associated arm  35  so that each ring  61  is rotated by virtue of the frictional engagement of its outer peripheral surface with one of the drive rollers  47 . The associated rotatable guide roller  54 , as noted above, can be adjusted in a somewhat radial direction relative to the outer peripheral surface of the table  17 , so that the relative position of a particular carrier ring  60  can be adjusted with respect to the rollers  47  and  54  engaged therewith. 
     As shown in FIG. 1, before placing the machine  10  in use, it is customary to enclose the sun gear  32  and upper end of its drive shaft  30  in a circular housing  70  which is supported on the inner ends of arms  35  and  36 . Also, each of three, similar, generally rectangularly shaped housings  71  is mounted on a different one of the three arms  35  to overlie and enclose the timing belt  48  and pulleys of the associated arm  35 . 
     While this invention has been illustrated and described in connection with only certain embodiments thereby, it will be apparent that it is capable of still further modification, and that this application is intended to cover any such modifications which fall within the scope of one skilled in the art or the appended claims.