US2576131A - Buffing apparatus - Google Patents

Description

BUF'FING APPARATUS 7 Filed Feb. 15, 1949 5 Sheets-Sheet l 62am?! law/Pr [raw NOV. 27, 1951 A, LYON 2,576,131

BUFFING APPARATUS Filed Feb. 15, 1949 5 Sheets-Sheet 3 ullllllllllllll ll Nov. 27, 1951 Filed Feb. 15, 1949 G. A. LYON BUFFING APPARATUS 5 Sheets-Sheet 4 Inf 22:72:71" 62020; $5597 [raw Nov. 27, 1951 G. A. LYON 2,576,131

BUFFING APPARATUS Filed Feb. 15, 1949' 5 Sheets-Sheet 5 Patented Nov. 27, 1951 UNITED STATES PATENT OFFICE BUFFING APPARATUS George Albert Lyon, Detroit, Mich.

Application February 15, 1949, Serial No. 76,479

The present invention relates to anapparatus for carrying out buffing or polishing operations.

In usual polishing operations, wherein rotating buffing wheels are brought into contact with different parts of the work as the same is rotatedi a block or rod of buffing compound against the periphery of the buffing wheel. Such manual treatment of the buffing wheel with the buffing compound has many inherent disadvantages. For one, it is dangerous to the operator because of the possibility of the operators arm being accidentally thrown against a moving part of the mechanism or against the moving workpiece.

Further, this method of applying a buffing compound is extremely wasteful as there is normally no means other than the operators skill for gauging the amount of buffing compound which is being applied to the wheel.- A definite minimum amount of buffing compound is necessary to adequately coat or impregnate the surface of the wheel, so that the buffing wheel will not be burned during the buffing operation. Hence, it is normal practice to provide an excess of the buffing compound for coating the surface of the wheel. Since buffing compounds are relatively expensive, this procedure is quite wasteful and represents a considerable part of the cost of any buffing operation.

Further, there is no assurance when a buffing compound is applied in this manner, that an even coating of the compound will be applied to the.

surface of the buffing wheel.

One of the main features of the present invention is that it provides a system whereby a buffing wheel is alternately contacted by a workpiece and by a block of buffing compound, each operation being carried out for predetermined periods of time and in such a manner that the buffing wheel always takes the same amount of buffing compound during each dressing operation, and always maintains the same alignment with the workpiece during the buffing operation.

In one preferred embodiment of the present invention, there is provided a tiltable housing which carries a buffing wheel thereon, the buffing of the workpiece being done at one end of the tilting movement, and the finishing application to the wheel of the buffing compound being carried out at the other end of such movement. Means are also provided whereby the tilting movement of the buffing wheel housing automatically indexes the 10 Claims. (Cl. 51-263) buffing compound toward the buffing wheel a predetermined amount to compensate for the amount of compound removed during the finishing operation. In addition, means are provided for extending the arc subtended by thetilting movement to compensate for the wear on the surface of the buffing wheel during the polishing operation. The aforementioned means are integrated into the assembly so that both functions are performed automatically.

As another feature of the present invention, there is provided a new type of holder for the bufiing compound designed in a manner such that there is a minimum of wastage of the buffing compound held therein. 7

It is, therefore, an object of the present invention to provide an apparatus for performing a polishing operation in which the loss of buffing compound is held to a minimum.

It is a further object of the invention to provide an apparatus for polishing operations with means therein for controlling the amount of buffing compound to be applied to the wheel.

It is a still furtherobject of the invention to provide an apparatus for polishing and buffing operations in which the buffing compound is automatically advanced a predetermined amount after each buifing operation, so that the buffing wheel takes off the same amount of compound during each operation.

Still another object of the present invention is to provide an apparatus for buffing assemblies which compensates for the wear of the surface of the buffing wheel itself during the buffing operation, and does so in an automatic manner.

A further object of the present invention is to provide an apparatus for applying a buifing com pound to buffing wheels without the hazards previously connected with this operation.

Other objects and features of the present invention will become apparent from the following description of the attached sheet of drawings, in which:

Figure 1 is an end elevational view of the assembly embodying my invention;

' Figure 2 is a side elevational view of the apparatus. 1

Figure 3 is a top plan view of the apparatus showing the buffing wheel in contact with a workpiece;

Figure 4 is an enlarged fragmentary sectional view of the indexing mechanism of the present invention taken along the line IV-IV of Figure 2;

Figure 5 is an enlarged, fragmentary, side the yoke I2. upon a base frame [1, from which depend bearinghousings l8 and l9. 7

receive a shaft 26 which is sta-tionarily held at, .its ends in supporting blocks 2| and 22 projecting from the base 23 of the assembly.

; ing a drive shaft 33.

wheel 31.

as ch annel beams 49. r

the bufling wheel in contact with the buffing com- V pound after a considerable portion of the compound has been used; V Figure 9 is a fragmentary, enlargedend elevational view of the holder containing a block of buffing compound; and a s Attached to the table 46 are a pair of bearing members 56 and 5| in which are journaled the smooth cylindrical end portions of a threaded lead shaft 52. The shaft 52 is threaded, as at 53, along the major portion thereof, and also has a reduced unthreaded portion 54. Rotation of the shaft 52 may be effected by operation of a ratchet wheel 55 keyed to one end thereof or by means of a manually operable wheel 56 located atthe opposite end thereof. As the shaft 52 is rotated, the rotation causes a movement of a sliding block 51 which is in threaded engagement with the shaft 52 and slideable along the table 46. -.Such movement of the block 51 causes a lever 58,

attached to the block. to pivot the arm 44 about the axisof the shaft 26 and-move the holder 46 Figure 10 is a perspective view of'the holder with the block of bufiing compound removedl As shown on the drawings:

Reference numeral I6 denotes in general a housing containing a pair of angularly disposed yokes II and |2 (Figures 1 and 2) secured together at their uppermost portions by means of bolts l3 and [4 which pass through flanges l5 and I6 of the yoke II and corresponding flanges on The yokes II and I2 are mounted The housings l8 and I9 Disposed within the housing I!) and within the yoke H and i2, is a supporting table 24 mounted from the base frame I1. Said table 24 is apertured at its corners to receive bolts 25, which are threaded through the base H of the housing I0 and held therein by means of nuts 28.

A strap 3| is anchored to said supporting table 24 and serves to retain thereon a motor 32 hav- The a conventional buffing wheel 31.

The housing I6 is capable of rocking movement about the shaft by means of the double acting cylinder 38 (Figures 1 and 2). The cylinder 38 may also be used to index the various workpieces into alignment with the surface of the bumng The operation of the cylinder 38 is conventional, as will-be readily appreciated by jthose'skilled in the art.

At one end of its rocking movement, as illustrated by the dotted lines of Figure l, the periphcry of the buffing wheel 31 is brought into contact with a solid block of bufiing compound 39 held '4! is fixedly secured to an arm 44. The arm 44 is mounted by means of a sleeve 45 for pivotal movement about the shaft 26.

To provide indexing of the assembly to compensate for both the wear on the bufling wheel .and the removal of buffing compound from the block 39 during each cycle of operation, a novel indexing assembly is herein provided. The in- Rotational torque produced of the motor 32 is supplied from the drive shaft 33 by means of V-belts 34 to a spindle 35. spindle 35 is journaled for rotation within a housing 36 carried by the yokes II and I2 and drives dexing assembly (Figures 1, 2, 4 and 5) consists turn rigidly secured to supporting means such and the buffing compound 39 a predetermined amount toward'the surface of the buffing wheel 31. As will be hereinafter described, the assembly is calibrated so that the eventual movement of the block ofbuffing compound 39 compensates exactly for the amount of surface worn from the buffing compound 39 during its contact with the bufiing wheel 31.

To impart the desired amount of rotation to the shaft 52 andthereby move the block of buffing the shaft 64 is rotatably held within aslot 65 of a bracket 66. This bracket 66 is fixedly secured to an arm 61. The arm 61 is rigidly secured, as by welding or the like, to a second arm 69 carried by the tilting housing NJ.

The operation of the indexing device is as follows:

As the tiltable housing In carrying the bufiing ,wheel 31 is tilted by the reciprocating action of the cylinder 38 to effect contact between the periphery of the bufiing wheel 31 and the block of buffing compound 39 as shown by the dotted line portion of Figure 1, the arm 69 swings downwardly and carries with it the arm 61 and the slide 66. The horizontal component of such motion is compensated for by movement of the roller 63 in the slot 65, so that the slide 66 moves only in a downward direction. As the slide 66 moves downwardly, the pawl 6| drops to a position below the next succeeding tooth on the ratchet wheel against the bias afforded by the spring 16. As is best shown in Figures 2, 3,

and 5, the pawl 6| is set back into a recess in the slide 60, the movement of the pawl 6| being limited by inclined faces 66a and 661; formed on the surface of the slide 66. With reference to Figure 5, the downward movement of the slide 66 will carry the pawl 6| from its position adjacent the tooth A of the ratchet wheel 55 to a position below the next tooth B. When the tiltable housing In is tilted in the opposite direction, the arms 69 and 61 force the slide 66 upwardly within the sleeve 59, and the pawl 6| will contact the base of the tooth B and rotate it into the position formerly assumed by the tooth A. It will be evident that the pawl 6| is free to pivot in one direction only, that is, during the downward stroke of the slide 60, since it is held against pivoting in the other direction by means of the faces c and 60d formed in the face of the slide 60. This rotation 9 th r ch t h el .55 tr nsmitted. to the shaft horizontally within the ways 16 and 11.

52 by virtue or the direct connection between the two elements, and causes the sliding block 51 to move forwardly toward the ratchet wheel 55. This movement is imparted to the buifing compound holder 4!] and the bufling compound 39 held therein by means of the lever 58 which is pivotally mounted to the sliding block 51 on one surface thereof by means of a pin 1] and to the arm 44 by means of a pin 12 (Figure 2). The pitch of the threaded portion 53 is such that the resultant movement imparted to the block of buffing compound 39 in the direction of the periphery of the buffing wheel 31 corresponds to the amount of bufling compound to beapplied to the surface of the wheel during each dressing operation. Normally, this will be on the order of .005 inch.

Thus, upon each cycle of tilting movement by the housing In, the buffing compound 39 is advanced the same predetermined amount toward the surface of the buffing wheel 31. It will be noted that the bufhng compound is automatically applied to the surface of the buff wheel at a point remote from the point where the bufiing wheel contacts the workpiece.

The time of contact between the buffing wheel 38 and a fixed workpiece W, shown in Figure 3,

vance the buffing compound toward the buffing wheel also functions to compensate for the wear on the buffing wheel during each buffing operation. In specific instances, this wear will amount to approximately .00075 inch for every operation.

To make this compensation, the assembly is provided with means for advancing the tilting arc of the housing and the buffing wheel so that the wheel and the workpiece are brought into the correct pressure relationship for each buffing operation.

To accomplish this purpose, there is provided a flanged plate 13 which is affixed to the sliding block 51 by means of bolts 14 and 15. The flanged plate 13 is slidable along ways 18 and 11 formed at the base of the horizontal table 46. of the sliding plate 13 slopes downwardly from the horizontal, and carries a bar 18 secured in a channel in the under surface of said plate 13. The limit to which the buffing wheel assembly can be tilted in the direction of the workpiece is determined by the point of contact between the bar 18 and an adjusting screw 19, which is threaded into a sleeve 80 held by the aforementioned arm 61. It will be noted that as the sliding block 51 moves horizontally along the horizontal table 46, the plate 13 and bar 18 will be advanced Thus, the adjusting screw 19 will contact a difierent point along the inclined base of the bar 18 during each movement of the bufiing wheel 31 toward the workpiece. The inclination of the bar 18 will determine the amount that the tilting movement of the buffing wheel will be displaced during each cycle. By the proper adjustment of the inclina- The base ments exactly equal to the radial shrinkage of the bufhng wheel due to wear in its contact with a workpiece.

As another feature of the present invention, I have herein provided a novel type of holder for the buffing compound which provides for maximum utilization of the rather expensive compound. The holder 40 comprises a base 8| (Figures 6 and 10) having a notch 82 along one edge thereof, and to which are secured a pair of upstanding wall portions 83 and 84 having upper outturned flanges 85 and 86. The spacing between the walls 83 and 84 is slightly larger than the thickness of the. buffing wheel 31, so that the buffing wheel 31 is movable within the holder assembly. The rear of the holder assembly is provided with an inclined backing member 81 having holes 91 therein to allow the bufling compound to become anchored within the holder as a result of the pressure exerted on the compound by the contact with the bufilng wheel. Extending from the backing member 81 to the base 81 is an arcuate backing piece 88 which has a radius of curvature corresponding approximately to the mean working radius of the buifing wheel 31.

The assembly may be filled by moulding a buffing compound 39 within the holder 49 and may be repeatedly reused.

The assembly shown in Figure 10 is inserted within a channel defined by the upturned flanges 42 and 43 of the arm 44 by means of two upstanding plates 89 and 99 (Figure 6) having a series of longitudinally extending notched channels 91. The plates 99 and 90 are provided with inclined sidewall portions 92 (Figure 9) which determine the extent to which the holder assembly can be inserted into the plates 89 and 98. The holder 49, containing the buffing compound 39, is inserted between the plates by sliding the base 8| into the appropriate set of channels 9| until the inclined sidewall 92 is in contactwith a rod 93, which is welded or otherwise secured to the base 8|. Figures 6, 8, and 9 show the condition where the holder 40 is inserted in the lowermost set of notches 9|. The holder 49 is locked in position by means of a locking screw 94 which threads into the notch 82 in the base 8|. The holder 4|] will be inserted in the lowermost set of notches while the buffing wheel has its maximum diameter, 1. e., before an appreciable amount has been worn from the surface of the bufiing wheel 31 by extended buffing operations.

When the block of bufling compound has worn down to a point where it is no longer usable, the holder 49 is released by threading back the screw 94 and a fresh block of compound in another holder is moved into the middle set of channels, a condition illustrated in Figure 7. As there shown, the use of the first block of bufiing compound over a number of cycles of bufling operation sufficient to completely use up the first block of compound results in a reduction of the periphery of the buffing wheel 31 from the original periphery represented by the dotted-line to that shown by the solid line. Thus, by inserting a new block of compound in the middle series of channels 9i, compensation is made for the wear on the bufling wheel occurring during the use of the previous block of compound. As will be noted from Figure 9, the line through the row of staggered adjusting screws 94, 95 and 98 is parallel to the inclined face 92 of the plate 99. Thus, the notch 82 is in alignment with the second locking screw 95 when the holder 40 is placed in the second series of channels.

tion, the tilting arc can be extended by incre- 76 After theme of the second block of compound,

7 'the holder is again removed and-a -new blockof compound inserted into the uppermost set of channels 9|. The notch 82 is then in alignment 'withthe adjusting screw 96 and the holder may be held between the plates 89 and 90 by the ad- -justment of the locking screw 96. 7

Upon the completion of the use of three separate blocks of buffing compound, the bufi'ing wheel 31 is normally reduced to a diameter which is no longer usable. When this occurs, the buffing wheel 31 is replaced and the indexing mechanism realigned. This realignment is accomplished by turning the operating handle 56 to move the sliding block 51 back and away from the ratchet wheel 55. The adjusting screw 19 is threaded back into the sleeve 80. The bufiing wheel is then brought into contact manually with the workpiece, the wheel is held against the work- 1 piece at the desired amount of pressure, and the screw 19 is then threaded against the bar 18 to maintain the desired pressure.

To summarize the operation of the device, the assembly provides a buffing wheel movable into position to buff a fixed workpiece at one end of its movement and to contact a bufiing compound at the other end of its movement. Means are provided for advancing the buffing compound toward the surface of the wheel operable when the wheel is out of contact with the buffing compound, so that the contacting surface of the solid bumng compound is returned to the same position in each cycle. At the same time, means are provided for incrementally extending the arc of movement of the wheel toward the fixed workpiece during each cycle of operation to compensate for shrinkage in the radius of the wheel due to wear,

It will be evident from the foregoing that I have here provided an apparatus for buffing operations in which the amount of buffing compound to be applied to the surface of the bufling wheel is carefully controlled and compensation is made for the wear of the bufling compound during each cycle of operation and also for the wear resulting to the surface of buffing wheel from contacting the workpiece.

I claim as my invention:

l. A buffing wheel assembly comprising a tiltable buffing Wheel adapted to buff a workpiece at one end of its tilting movement, means for holding a buffing compound in contacting relation with the surface of said wheel when said wheel is at the other end of said tilting movement, means for advancing said holding means a predetermined distance towards said wheel operable when said wheel is out of contact with said bufiing compound, and means for advancing said wheel towards said workpiece a predetermined distance before each bufilng operation.

2. A bufling wheel assembly comprising a buffing wheel movable into position to buff a workpiece at one end of its movement, means for holding a buffing compound in contact with the surface of said wheel when said wheel is at the other end of said movement, means operable while said wheel is out of contact with said buffing compound for advancing said holding means a predetermined distance towards said Wheel, and means automatically increasing the length, of movement of said wheel towards said workpiece to compensate for shrinkage in the radius of said wheel due to wear.

3. A bufling wheel assembly comprising a tiltable frame, a buffing Wheel carried by said frame ada t d bugawor r ece t one and ,ofits 8 tilting movement, an arm pivotally mounted about the tilting axis of said frame, means carried by said arm for holding a buffing compound in contact with the surface of said wheel when said wheel is at the other end of said tilting movement, means for advancing said holding means a predetermined amount towards said wheel operable while said wheel is out of contact with said buffing compound, and means for incrementally increasing the length of travel of said wheel towards said workpiece to compensate for the amount of surface worn from said wheel during each bufing operation. V

4. A buifing wheel assembly comprising a tiltable frame, a bufling wheel assembly carried by said frame adapted to buff the surface of a workpiece at one end of its tilting movement, means for holding a buffing compound against the surface of said wheel at the other end of said tilting movement, means for advancing said holding means a predetermined amount towards said wheel operable when said wheel is out of contact with said buffing compound, and means cooperating with said advancing means to extend the arc of said tilting movement between successive bufling operations to compensate for the amount of surface worn from said wheel during each buffing operation.

5. A buffing wheel assembly comprisinga tiltable frame, a buffing wheel carried by said frame adapted to buff the surface of a workpiece at one end of its tilting movement, an adjustable limiting means for limiting the extent of tilting move.- ment, means for holding a buffing compound against the surface of said wheel at the other end of its tilting movement, means for advancing said holding means a predetermined amount toward the bufiing wheel operable when said buffing wheel is out of contact with said bufilng compound, and means for extending the arc of displacement of said frame operable after each buffing operation to compensate for wear on said wheel during each buffing operation. a

6. In a bufiing wheel assembly having, a, buffing wheel adapted to-alternately buff a workpiece and contact a bufiing compound, indexing means for advancing said buifing compound a predetermined amount towards said wheel after each buffing operation comprising a holder for said buffing compound, an arm extending from said holder, a lever pivotally mounted to said arm, a threaded shaft, a block in threaded engagement with said shaft and movable therealong, said block being pivotally connected to the other end of said lever, and pawl and ratchet means for periodically rotating said shaft to thereby cause displacement of said lever, said arm, and said holder a predetermined distance towards said bufling wheel.

7. In a buffing assembly having a rotatable bu'ifing wheel adapted to periodically contact a block of solid buffing compound, means for holdingsaid compound in contactwith the surface of said wheel comprising an arm, a pair of upstanding .plates secured to said arm, said plates having ward said tiltable bufiing wheel, said mechanism comprising a holder for said compound, an arm extending from said holder pivotally mounted about said axis of tilting movement, a lever pivotally secured to one end of said arm for advancing the arm and holder to said wheel, and means actuated by the tilting movement of said assembly for moving said lever and thereby said arm and holder a predetermined distance toward said Wheel during the tilting movement thereon.

9. A bufling assembly including a buflmg wheel with a periphery positioned for contacting a workpiece, means for moving the buffing wheel through an arcuate path into engagement with the work, said means being operable to move said wheel out of contact with the work and into contact with a buifing compound such that a predetermined amount of buffing compound is applied to said wheel, and means for contemporaneously advancing the compound toward the Wheel during each cycle of movement of said bufiing wheel to compensate for the use of said compound.

10. A bufiing assembly comprising a bufiing wheel with a periphery positioned for contacting a workpiece, means for moving the bufiing wheel into engagement with the work and operable to move the bufling wheel out of contact with the work and into contact with a buffing compound such that a predetermined amount of bufling compound is applied to said wheel, advancing means for moving the compound toward the wheel, and compensating means for adjusting the movement of the wheel to compensate for the extent of surface removed from said wheel during each bufling operation, said advancing means and said compensating means being operable during each cycle of motion of said bufiing wheel.

GEORGE ALBERT LYON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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