US3441968A - Automatic buffing machine - Google Patents

Description

Sheet INVENTOR FRANK H. KRAMEN F. H. KRAMEN AUTOMATIC BUFFING MACHINE ME u 5 7 me Q 2 g .Q mm \Qwh e M n: a R v I w a Na h IH i g e T T we i? l we: i ll e NW i we e e 3 n e 3% i 8 VP. m e we Mm B a mm 1 I WM vs Mm www a n we we e e NE & e

May 6, 1969 Filed Jan. 23, 1967 ATTORNEY Filed Jan. 23, 1967 F. H. KRAMEN I 3,441,968

AUTOMATIC BUFFING MACH INE Sheet 2 of2 1.\ 'VE.'\TOR. FRANK H. KRAMEN mam ATTORNEY United States Patent US. CI. 15-97 Claims ABSTRACT OF THE DISCLOSURE The bufiing machine of this invention includes a buff assembly having individual buffs mounted for uninterrupted synchronized movement in sequence with a series of successive workpiece holders supported on a continuously traveling conveyor for movement toward and away from the butt assembly while in registry with a buff.

This invention generally relates to bufiing machines and has a primary object the provision of an improved automatic bufiing machine for effecting registry of-polishing heads and workpieces in proper nesting relation to provide high quality product finishes essentially free of uneven wear in a high production operation wherein the workpieces are being continuously advanced.

Another object of the invention is to provide an improved high production buffing machine capable of finishing various workpieces of irregular shapes andsizes in a continuous machine operation involving minimal lost time and which provides an extensive danger-free work area for rapidly loading and unloading workpieces.

A further object of the invention is to provide a machine of the above described typejfor effecting a buffing operation wherein a buff axis is maintained at a constant height and wherein workpieces are placed in registry with a buff before contact is effected therebetween for minimizing uneven surface wear of the workpieces, while also compensating for buff wear.

Another object of the'invention is to provide an improved bufling machine in which successive workpieces supported on a continuously traveling conveyor are automatically registered in sequence with successive buffs and wherein the buffs progress in registry with the workpieces during bufling engagement thereb'etween.

A further object of the invention is to provide a machine of the type heretofore described in which the axes of the buds and the position of the associated workpieces are maintained in preselectable relationship during synchronized travel in bufiing engagement and wherein the amount which the buds lead or trail the associated workpieces can be preselected and maintained during engagement of each buff and its associated workpiece.

A still'further object is to provide a machine as heretofore described in which the synchronized travel of bufis and workpieces is along .a common arcuate path of constant radius and wherein the bull? shafts are radially disposed relative to the travel path and are adjustable to lead or trail the associated workpieces by a preselectable angle of travel.

Still another object'of the invention is to provide an improved buffing machine which is readily installed to provide reliable operation over a long service life with minimal maintenance-requirements.

' A still further object is to provide a machine of the "ice above described type particularly suited for enlarging and reducing the bufling capacity of the machine to meet changes in production requirements.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a side elevational view, partly broken away and partly in section, showing a preferred embodiment of a bufling machine constructed in accordance with the present invention; and

FIG. 2 is a plan view, partly broken away, of the bufling machine of FIG. 1. I

Referring now to the drawings in detail wherein a preferred embodiment of a 'bufiing machine constructed in accordance with this invention is illustrated, a stationary frame 10 is shown including a pair of beams 12, 14, resting in parallel spaced relationship on a floor 15, and supporting a pair of gear boxes 16, 18 which are spaced apart and fixed upon beams 12, 14. A pair of upstanding pedestals 20, 22 are mounted upon gear boxes 16, 18, and a pair of horizontally disposed turntables 24, 26 are respectively supported on the same level above floor 15 for rotation on the pedestals 20, 22.

As best seen in FIG. 2, turntable 24 is shown as having a pair of notched drive plates 28, 30 suitable secured together in vertically spaced relation on a shaft 31 for simultaneous rotation, and a series of peripheral notches are preferably formed in vertical alignment with one another on plates 28, 30 in groups of three equally spaced nests or notches such as at 32, 34, 36. The turntable 26 is shown as being of greater diameter than that of turntable 24, but is of similar construction and like numerals followed by the letter a have been utilized to identify like parts.

By virtue of the above described arrangement, the turntables 24, 26 are adapted for supporting an endless conveyor 38 comprised of a series of substantially identical carriages 40 coupled together at spaced intervals by links 42 having vertical sleeves 44 at their opposite ends for receiving pivot pins 46 pivotally connecting the links to the ends of the carriages 40. Each of the carriages 40 are engageable witha peripheral portion of the turntables 24, 26 upon being received in the above mentioned notches, and the endless conveyor 38 may be advanced by rotation of the turntable 24, e.g., in a clockwise direction as viewed in FIG. 2 upon energizing an electric motor, not shown, for rotating a drive shaft 48 drivingly connected to suitable gearing within gear box 16, the output of which is transmitted by shaft 31 to the turntable 24 of its rotary movement in turn effects simultaneous rotation of turntable 26 in unison therewith via the endless conveyor 38.

Proper positioning of the carriages 40 on the periphery of the turntables 24, 26 is facilitated by the provision of locating rollers 50 and 52 rotatably mounted on upper and lower portions of each pivot pin 46 in the preferred embodiment. In addition, each carriage 40 has an enlarged central housing 54 through which a vertical shaft 56 (FIG. 1) extends, the shaft 56 being supported within the housing 54 for both rotary and axial movement. The

vertical shaft 56 of each carriage 40 is provided with an enlarged lower end portion 58 positioned below the conveyor 38 and its opposite upper end portion, not shown, is suitably fixed to a workpiece holder 60 disposed above the plane of the upper drive plates 28, 28a of the turntables 24, 26, and annular stop plates 62 and 64 as illustrated are fixed relative to the upper and lower portions of the housing 54.

A sprocket 66 is mounted for rotation between the lower portion of each housing 54 and its stop plate 64, and it will be understood that the vertical shafts 56 can be splined, e.g., to the sprockets 66 thereby to couple the shaft and sprocket of each carriage 40 for simultaneous rotary movement while yet providing for axial movement of the shaft 56 relative to the sprocket 66.

In the preferred embodiment, each carriage 40 is desirably provided with expansible protective jackets 68, 70 suitably attached for enclosing upper and lower portions of the shaft 56 projecting from the carriage housing 54 whereby the entry of dirt, dust and similar undesirable particles between working parts of each carriage housing is essentially eliminated.

Referring now to the turntable 26, a turret assembly 72 is shown having a spider hub 74 and a underlying horizontal plate portion 75 which removably supports and locates the spider hub 74 with locating pins 76 on a headstand 77. The headstand 77 is concentric with the turntable 26 and is mounted upon the upper plate 28a of the turntable 26 for rotation therewith upon rotary movement of the turntable 24. The headstand 77 is angularly adjustable relative to the upper plate 28a about their common axis by bolts 78 which adjustably secure the headstand 77 to the upper plate 28a through arcuate slots 79 in a flange portion 80 of the headstand 77.

A plurality of turret mounts 81 project radially outwardly of the spider hub 74 in equiangularly spaced relation corresponding to the angular spacing between each group of peripheral notches formed on the turntable 26, there being eight turret mounts 81 shown in the preferred embodiment. Each turret mount 81 rotatably supports a buff shaft or spindle 82 for rotation with its longitudinal axis extending radially outwardly of the spider hub 74 generally perpendicular to the common rotational axis of the turret assembly 72 and the turntable 26, and a bevel gear 83 is provided on the inner end of each spindle 82 in meshing engagement with a ring gear 84 fixed upon the upper end of a vertically disposed spindle drive shaft 86. The latter extends axially downwardly of the spider hub 74 and is drivingly connected through suitable gearing in gear box 18 to 'a main drive shaft 88 power operated, e.g., by an electric motor, not shown, for rotating the spindles 82 at a preselected speed of operation. A buff wheel 90 is mounted on each spindle 82 so as to be spaced above a peripheral portion of the turntable 26, and each buff wheel 90 is fixed to its spindle between retaining members 92 on opposite axial ends of the buff wheel 90 by a nut 94 threadedly secured to the outer end of each spindle 82.

By virtue of the above described construction, the aforementioned angular adjustment of the headstand 77 relative to the turntable 26 about their common axis provides for proper location of the spindles 82 forward, on or back of the center of rotation of the carriage shafts 56 upon positioning the carriages 40 in the turntable notches 34a for appropriate buff action with respect to the workpieces 96.

The bufling machine of this invention is particularly suited to continuously advance workpieces, such as the automobile wheel disc shown at 96, without interruption in a manner heretofore associated with high production continuous machines while additionally providing for proper nesting of the buff wheels 90 with workpieces of various sizes and shapes to effect high quality finishing, free of uneven wear conventionally obtained only by 4 slower indexing rotary machines customarily requiring a dwell and interlock.

More specifically, a plurality of generally radially extending levers 98 corresponding in number to the spindles 82 are suspended below the turntable 26 for pivotal movement in a vertical plane extending through the 1ongitudinal axis of its corresponding spindle 82. Each lever 98 is pivotally connected to a pivot pin 100 secured to a bracket 102 depending from the lower drive plate 30a of the turntable 26 and is of sufficient length whereby its outer end 101 is disposed below a peripheral portion of the turntable 26 for registry with the lower end portion 58 of a carriage shaft 56 and for lifting the same into a raised position.

An inner end of each lever 98 is provided with a rotatable cam follower roll 104 for engaging a stationary cam 106 circumferentially extending about the pedestal 18 and having a downwardly sloping lift control surface 108 for pacing the lifting operation of the levers 98. A downward driving force is effected on each lever 98 by a vertical plunger 110, the lower end of which is pivotally connected thereto adjacent the cam follower roll 104 of the lever 98, and each plunger 110 is connected to and actuated by an associated air motor such as at 112, each of which is individually mounted on the lower plate 30a of the turntable 26 and connected to a suitable pneumatic circuit in accordance with conventional techniques.

To provide proper nesting of the buff wheels 90 with the workpieces carried by the holders 60, the sloping lift control surface 108 of the cam 106 is in a preselected angular position relative to the path of movement of the conveyor 38 such that proper registry is first obtained between each buff wheel 90 and a workpiece holder 60 before any lifting action is applied by the lever 98. Accordingly, an entrance edge 1-13 of the sloping surface 108 is angularly positioned at a point at which the path of movement of the workpiece holders 60 of the conveyor 38 is tangential to the orbital path of movement of the buff wheels 90, thereby ensuring that each carriage 40 will be properly located within peripheral notches 34a of the turntable 26 for travel therewith and the carriage shaft 56 will be in proper registry with a bufl? wheel 90 and the outer end of a lever 98 before the workpiece holder 60 is raised toward the buff wheel 90. The entrance edge 113 of the sloping surface 108 thus corresponds to an entrance end of a registry station and as the buff wheels 90 and the workpiece holders 60 are advanced in timed relation, the cam follower roll 104 of each lever 98 travels down the sloping surface 108 under the driving force of its air motor 112 whereby each of the shafts 56 are successively raised by the outer ends of the levers 98 to thereby raise the workpiece holders 60* in sequence toward the continually advancing buff wheels 90 to effect bufiing contact.

Buffing of the workpiece 96 will continue uninterrupted during the subsequent rotary movement of the conveyor 38 and buff wheels 90 in unison throughout an angular displacement hereafter referred to as a buffing zone. Cam 106 includes an upwardly sloping surface 114, substantially identical to surface 108, having an upper terminal edge 116 generally diametrically opposed to edge 113, and this additional sloping surface 114 corresponds to a separation station whereby each cam follower roll 104 is forced upwardly to cause downward pivotal movement of the outer ends of the levers 98 for retracting the holders 60 with the assistance of gravity. Each workpiece is then completely separated from buffing contact with its bufling wheel 90 after rotation through an angular displacement of about degrees from the entrance end of the registry station, defined by the edge 113 of the cam 106, to an exit end of the separation station defined by the edge 114 of the earn 106.

It will now be apparent that each of the workpieces piece carried thereby is constantly rotated during travel through the buffing zone. For this reason, a link chain 120 is provided to extend circumferentially about the peripheral margin of the turntable 26 and is fastened at opposite ends to rods 122, 124 supported in bearing brackets 126, 128. The latter are in turn fixed to L- shaped stanchions v130, 132 respectively secured in opposition to one another to supporting beams 12, 14.

The link chain 120 thus is adapted for meshing engagement with the sprockets 66 to walk the same along the length of chain 120 causing the sprockets 66 to rotate in a counterclockwise direction as viewed in FIG. 2 whereby rotation of each sprocket is transmitted by the carriage shaft 56 to the holder 60, the sprockets-66 and the shafts 56 being rotatably couipled for simultaneous rotary movement as described above. Thus, it will be seen that each workpiece 96 is counter-rotated in a direction opposite the angular direction of movement of the butf wheels 90 throughout travel of the workpieces through the bufiing zone.

In the preferred embodiment, proper tensioning of the chain 120 is facilitated by suitable springs 129, 131 coiled about rods 122, 124 and seated between brackets 126, 128 and nuts 134, 136 threadably secured to the ends of rods 122, 124 whereby a preselected tension may be effected on chain 120 by adjusting nuts 134, 136.

A typical operating cycle of a machine embodying this invention involves loading workpieces 96 into the holders 60 while their carriages 40 are engaged with the turntable 24. As the turntable 24 is driven to advance the conveyor 38 and to thereby rotate the turntable 26 and its turret assembly 72, each of the holders 60 is successively placed in registry with a buif wheel 90 before contact is established. The lifting operation applied by the levers 98 to the shafts 56 is paced by the cam 104 and the air motors I112 furnish the driving force to raise the holders 60 where-upon the workpieces 96 are lifted into and dropped out of contact with the buff wheels 90 while in registry therewith as the turret assembly 72 is rotated in unison with the carriages 40. In addition, each work holder 60 is automatically counterrotated in a direction opposite the angular direction of travel of the conveyor 38 for ensuring a properly buffed, even finish on the workpieces.

A bufiing machine of the above described structure provides for proper nesting contact between each workpiece and a buif wheel which is automatically established in a high speed production operation providing high quality polishing and finishing while substantially eliminating uneven buff wear. In addition, the described structural arrangement significantly facilities loading and unloading of the workpieces in a position removed from the bufiing zone whereby an operator is provide freedom of movement to work efiiciently in complete safety.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

I claim:

-1. An automatic buffing machine adapted for continuously feeding workpieces along a path and comprising a frame,

a buff and an endless conveyor supported for movement on the frame,

the conveyor having a workpiece holder continuously movable in timed relation to, with and away from the buff along a path including a registry station, a bufiing zone and a separation station,

the buff and the workpiece holder being in spaced registry within the registry station and at least one of the last two named elements being movable toward the other thereof while in registry for effecting bufling contact in the bufling zone.

2. The bufiing machine of claim 1 further including control means selectively operable in response to the workpiece holder passing into the registry station for moving the workpiece holder toward the buff and for presenting a workpiece thereto in buffin-g contact in the buffing zone.

3. The bufling machine of claim 1 wherein the buff is continuously operable at a constant level relative to the conveyor, and

wherein the workpiece holder of the conveyor is mounted for reciprocal movement toward and away from the buff while in registry therewith.

4; The buffing machine of claim 1 wherein the buff is mounted for rotary movement on the frame and is also supported thereon for orbital movement in one angular direction about an axis generally perpendicular to the rotational axis of the buff.

5. The bufiing machine of claim 4 wherein the path of movement of the workpiece holder is tangential to the Orbital path of movement of the butf at an entrance end of the registry station and an exit end of the separation station.

6. The buffing-machine of claim 4 wherein the workpiece holder is mounted on the conveyor for rotation in a direction opposite said one angular direction while in registry with the buff and is also supported on the conveyor for reciprocal movement generally perpendicular to the direction of movement of the conveyor, toward and away from the buff while in registry therewith.

7. The bufling machine of claim 1 wherein the frame further includes a driven turntable mounted for rotation in a generally horizontal plane,

the conveyor being supported on peripheral portions of the turntable for movement in unison therewith, and

a spindle mounted on the turntable supporting the buff for rotation above a peripheral portion thereof and for orbital movement in one angular direction in timed relation to the turntable about the rotational axis thereof in a generally horizontal plane spaced above the turntable.

8. The buffingmachine of claim 7 further including a lever for actuating the workpiece holder, the lever being pivotally mounted to the turntable below the same for swinging movement in a vertical plane extending through a longitudinal axis of the spindle,

biasing means acting upon the lever for urging the workpiece holder into a raised position,

a cam fixed to the frame, and

a cam follower connected to the lever for lowering the workpiece holder into a retracted position as placed by the cam.

9. The machine of claim 7 further including a sprocket carried by the conveyor and rotatably coupled to the workpiece holder for imparting rotation thereto, and

a horizontally disposed chain carried by the frame and extending circumferentially of the turntable for meshing engagement with the sprocket whereby upon movement of the conveyor along said path, the sprocket is walked along the chain for rotating the workpiece holder in a direction opposite said one angular direction.

10. A bufiing machine of claim 7 further including mounting means securing the spindle relative to the turntable with the spindle axis in a generally horizontal plane, the mounting means being adjustable for selectively vary- 7 8 ing the positional arrangement of the spindle axis relative 2,886,165 5/1959 Eger 198-19 to the workpiece holder. 3,313,392 4/ 1967 Stott et a1. 19819 References Cited FOREIGN PATENTS 252,818 10/1912 Germany.

UNITED STATES PATENTS 5 1 40 133 19 5 France.

2,262,697 11/ 1941 Pearson 15--101 2,872,693 2/1959 A d at a]. WALTER A. SCHEEL, Przmary Exammer.

2,765,590 10/ 1956 Belejack et a1 198-19 L. G. MACHLIN, Assistant Examiner.

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