US3024575A

US3024575A - Apparatus for polishing articles

Info

Publication number: US3024575A
Application number: US638767A
Authority: US
Inventors: Peter M Dreiling
Original assignee: HI LITE POLISHING MACHINE CO I
Current assignee: HI LITE POLISHING MACHINE CO I; HI-LITE POLISHING MACHINE Co Inc
Priority date: 1957-02-07
Filing date: 1957-02-07
Publication date: 1962-03-13
Anticipated expiration: 1979-03-13

Description

March 13, 1962 P. M. D RElLlNG 3,024,575

APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 9 Sheets-Sheet l INVENTOR. PETER M. DREILING %4Zuu (ex/ 4:44

At iorneys March 13, 1962 P. M. DREILING 3,02

APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 9 Sheets-Sheet 2 PETER M. DREILING %mm KM March 1962 P. M. DRElLlNG APPARATUS FOR POLISHING ARTICLES 9 Sheets-Sheet 3 Filed Feb. 7, 1957 FIG. 5.

INVENTOR M. DREILING FIG. 4.

March 13, 1962 P. M. DREILING APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 9 Sheets-Sheet 4 FIG. 6.

mn I VIII INVENTOR. 1 PETER M, DREILING BY \v Attorneys 9 Sheets-Sheet 5 INVENTOR. PETER M. DREILING jaw z ww Attorneys March 13, 1962 P. M. DREILING APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 March 13, 1962 P. M. DREILING 3,024,575

APPARATUS FOR POLISHING ARTICLES Filed Feb. '7, 1957 9 Sheets-Sheet 6 INVENTOR. PETER M. DREILING Attorneys March 13, 1962 IN 3,024,575

APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 9 Sheets-Sheet 7 FIG. l4. FIG. I5. FIG. l6.

INVENTOR. PETER M. DREILING Attorneys March 13,1962 P. M. DREILING APPARATUS FOR POLISHING ARTICLES Filed Feb. 7, 1957 9 Sheets-Sheet 8 INVENTOR. PETER M. DREILING FIG. 2|.

United States Patent Ofifice 3,024,515 Patented Mar. 13, 179,62

ration of Wisconsin Filed Feb. 7, 1957, Ser. No. 638,767 25 Claims. (Cl. 51-3) This invention relates to an automatic power-driven apparatus for polishing or otherwise finishing a workpiece.

The present invention is directed to an apparatus for grinding, polishing, bufiing or otherwise finishing an irregularly shaped workpiece, and is particularly directed to the complete and automatic finishing of aworkpiece having side walls and inside corners such as electric frying pans, stainless steel sinks, cookware, etc.

According to the invention, the workpiece is finished by a series of abrading or polishing members which are successively moved to a position above the workpiece and subsequently lowered into contact with the workpiece. The workpiece itself is moved in a series of movements so that successive increments of the surface of the workpiece move relatively into contact with the abrasive member in a given pattern to finish a specific portion of the surface of the workpiece.

More specifically, the workpiece is given three separate and distinct movements which are arranged in automatic sequence. The movements are designed to finish specific surfaces or angles on the inside or outside of the workpiece. Similarly, the a-brading members to be employed during each movement of the workpiece are designed to effectively finish that particular portion of the workpiece on which the abrading member is acting.

The abrading member is disposed in floating contact with the workpiece and may take the form of an abrasive wheel, belt or the like which is moved into contact with the moving workpiece. By the course of all three movements of the workpiece and the use of the various abrasive members during these movements, all parts of the inside surface are completely finished including the side wall surfaces and the corners of the workpiece.

In the first of its movements, the workpiece is rotated while at the same time the axis of the workpiece is oscillated in a linear path.

The second movement is a true rotary movement in which the workpiece is rotated around the central axis thereof. In the third movement, the workpiece is moved parallel to the side walls and rotated around the corners thereof and thus the center of the workpiece moves or oscillates in two directions during the movement of the workpiece.

While the invention primarily relates to polishing or buffing of the inside of cookware, sinks, etc., it can also be used for polishing or bufling the outside surfaces of the members.

Although the principal use of the invention is for polishing or bufiing metal ware, it can also be used on any number of other products such as wood or ceramic materials. In addition, the apparatus can be used to finish ware of irregular shape such as square, oval, round, triangular, etc., having deep or shallow side walls which extend perpendicular to the bottom surface of the workpiece or which extend at an angle to the bottom surface.

Other objects and advantages of the invention will ap pear in the course of the following description.

The drawings illustrate the best mode presently contemplated for carrying out the invention.

In the drawings:

FIGURE 1 is a top plan view of the apparatus of the invention;

FIG. 2 is a view taken along line 2-2 of FIGURE 1;

articles.

FIG. 3 is a view taken along line 33 of FIG. 2 with parts broken away and sectioned;

FIG. 4 is an enlarged fragmentary side elevation of the chain tensioning apparatus for the chuck drive mechanism; FIG. 5 is a section taken along line 5-5 of FIG. 4;

FIG. 6 is an enlarged vertical section of the chuck drive and supporting mechanism;

FIG. 7 is an enlarged fragmentary vertical section of the central post showing the attachment of the heads and, the head lowering and raising apparatus;

FIG. 8 is a view taken along line 88 of FIG. 7;

FIG. 9 is an enlarged top plan view of a head with parts broken away and sectioned;

FIG. 10 is a side elevation of the structure shown in FIG. 9;

FIG. 11 is a side elevation of the base housing with parts broken away and sectioned;

FIG. 12 is an enlarged top plan view of the backing bar mechanism with parts broken away and sectioned;

FIG. 13 is an end view of one of the heads;

FIG. 14 is a top plan view of the index drive mechanism at the start of operation with the heads 45 out of alignment with the chuck;

FIG. 15 is a View similar to FIG. 14 showing the looking pin in engagement with the index disc and the drive pawl out of engagement with the disc;

FIG. 16 is a view similar to FIG. 14 showing the drive pawl in position to engage to the next succeeding notch in the index disc;

FIG. 17 is a diagrammatic view showing the motion of the chuck and workpiece when the chuck support shaft is not restrained in movement;

FIG. 18 is a diagrammatic view showing the motion of the chuck and workpiece when the chuck support shaft is restrained in movement in both a lateral and longitudinal direction with respect to the direction of chain travel;

FIG.19 is a diagrammatic view showing the motion of the chuck and workpiece when the chuck support shaft is restrained in movement in a direction longitudinally of the direction of chain travel;

FIG. 20 is a side elevation of the lower head of FIG. 1;

FIG. 21 is a wiring diagram of the electrical control system of the apparatus;

FIG. 22 is a continuation of the wiring diagram of FIG. 21;

FIG. 23 is a plan view of a modified sprocket having teeth extending around the entire periphery; and

FIG. 24 is a second modified form of sprocket for use with the invention.

The drawings illustrate an apparatus for polishing or otherwise finishing the inside and bottom surfaces of containers such as frying pans, kitchen sinks or other similar The apparatus is designed to polish or finish the bottom, side walls and corners of the workpiece in an automatic operation by moving the workpiece in a series of different movements while simultaneously engaging the workpiece with a corresponding series of working heads designed to polish a particular portion of the workp1ece.

The apparatus comprises, in general, a base 1, a work chuck 2 adapted to support and move the workpiece 3 during the polishing operation, and a plurality of abrading

heads

4, 5, 6 and 7 mounted on a drum or turret 8 to rotate into indexed positions for successive operations upon the workpiece.

The base 1 may have any suitable construction and is shown as a rectangular box-like housing having four sides 9 and a flat top plate 10. The base is suitably reilnzforced by corner angle plates 11 and side wall stiffeners The chuck 2 is carried above plate 10 and on the upper end of a vertical shaft 13 which extends downwardly through a large central opening 14 in the plate. The shaft 13 is supported inside base 1 by an extensible arm 15 pivotally carried by a vertical post 16 secured near one corner of the base 1.

The arm 15 has two end sections pivotally joined, as at 17, on a vertical axis disposed centrally of the arm, whereby the arm may be folded and extended as desired to give chucks 2 and workpiece 3 various horizontal movements.

The upper surface of chuck 2 is provided with centering bars 18 which serve to properly align the workpiece on the chuck surface. As shown in the drawings, the workpiece 3 is a shallow pan having a bottom and inner side walls to be polished or otherwise finished. The pan is shown having four sides although it is contemplated that the pan may have any desired configuration such as circular, elliptical, polygonal. etc.

To firmly hold the workpiece 3 on the upper surface of the chuck 2, the support shaft 13 is hollow and the hollow interior 19 of the shaft communicates with an opening 20 in the chuck. A vacuum is drawn through the hollow interior of shaft 13 by any suitable evacuating apparatus and the vacuum tends to hold the workpiece 3 firmly on the upper surface of the chuck 2.

The lower surface of the chuck 2 carries a generally square cam 21 having an inner cam surface of the same size and shape as the inner surface of the workpiece 3. The cam 21 is disposed axially of the chuck and workpiece, and a cam follower 22 is adapted to ride against the inner surface of the cam 21. Cam follower 22 is rotatably supported on a cam follower plate 23 secured diagonally across the base housing. The ends of the cam follower plate 23 are secured to the side wall stiffeners 12.

The chuck 2 is driven in a series of paths of movement by means of sprocket 24 which is secured to support shaft 13. A pair of supporting plates 25 are secured to the shaft 13 on either side of the sprocket 24. As shown in the drawings. the sprocket 24 has a generally square shape corresponding to the shape and size of the workpiece 3 and can] 21.

While the sprocket 24 is shown in FIG. 3 as having a series of teeth extending only around the corners thereof, it is contemplated that a sprocket 24a, as shown in FIG. 23, having teeth extending completely around the periphery may be used, or four small fixed sprockets 24b located at each corner of the square configuration may be employed as shown in FIG. 24.

The sprocket 24 engages an endless chain 26 which is supported by a drive sprocket 27 and an adjustable idler sprocket 28. The drive sprocket 27 is driven by a motor 29 secured to one of the side walls 9 and the chain 26 travels through a slot 30 in the side wall. The drive shaft 31 of the motor carries a pulley 32 which is connected by a belt 33 to a pulley 34 on the shaft 35 of a worm drive 36. Rotation of the worm drive 36 is trans mitted through suitable gears located in gear box 37 to shaft 38 which carries the drive sprocket 27.

To maintain spring tension on the chain 26 and also permit the chain to deflect during certain movements of the chuck 2 and sprocket 24. a guide bar 39 is secured to each end of the idler sprocket shaft 40. The bars 39 are adapted to slide within ways defined by bars 41 attached to upper and

lower support plates

42 and 43. The inner ends of

plates

42 and 43 are secured to side wall 9 while the outer ends of the plates are connected by an end plate 44.

The outer ends of guide bars 39 are connected together by a vertical bar 45 and a stud 46 is secured to bar 45 and extends outwardly through a suitable opening in end plate 44. The stud 46 carries a spring 47 which is interposed between end plate 44 and an adjustable nut 48. With this construction the spring 47 urges the idler sprocket 28 outwardly but permits the sprocket to move inwardly toward drive sprocket 27 during deflections of the chain.

As previously set forth, the support shaft 13 and chuck 2 are free to move universally in a horizontal plane with respect to post 16. With a side edge of the sprocket 24 in engagement with chain 26, the sprocket and the chuck 2 move longitudinally of the chain. During this longitudinal movement, the cam follower 22 rides against the corresponding side Wall of the cam 21. When the cam follower 22 reaches the corner of the cam, longitudinal movement of the chuck 2 and sprocket 24 with respect to the direction of chain travel is stopped and the chain engages the teeth at the corner of sprocket 24 thereby pivoting the chuck and sprocket around that corner. This movement is best seen in FIG. 17. If the chain 26 is held against lateral movement, both the chuck 2 and sprocket 24 move laterally away from the chain as they pivot around the corner.

After pivoting about the corner the next succeeding side of the sprocket 24 engages the chain and the cam follower then rides along the corresponding side of the cam. Once again the chuck will move longitudinally of the chain until the cam follower reaches the next succeeding corner of the cam. When the cam follower 22 reaches this corner of the cam the sprocket 24 and chuck 2 will again be pivoted around the corner in the manner described above. This procedure is repeated throughout the cycle of movement.

To hold the chain 26 against lateral deflection as the sprocket 24 pivots about its corner, a backing bar 49 is disposed against the inner surface of the portion of the chain traveling in engagement with the sprocket 24. The backing bar 49 is supported by a pair of brackets 50 at each end of the bar and the brackets 50 are connected to one end of a bell crank 51. Each bell crank 51 is fulcrumed about a pin 52 which is secured to the upper surface of the bell crank. The upper end of pin 52 receives a nut 53 and the pin is journalled within a bearing 54. The upper end of bearing 54 is provided with a generally oval head 55 and the head is secured by bolts 56 to the lower surface of plate 23.

To move the backing bar 49 toward and away from the chain 26, the outer end of each bell crank 51 is connected by a pair of connecting bars 57. The ram or piston rod 58 of a double acting air cylinder 59 is pivotally connected to the connecting bars 57 by a link 60. The outer end of the cylinder 59 is pivotally supported by a bracket 61 which is secured to the outer surface of side wall 9. As the ram 58 of cylinder 59 is extended, the bell cranks 51 are pivoted to move the backing bar 49 away from the chain 26. Conversely, as the ram 58 is withdrawn into the cylinder the bell cranks are pivoted in the opposite direction to move the bar 49 into engagement with the chain 26.

If the backing bar 49 is supporting chain 26 and the chuck shaft 13 is free to move both laterally and longitudinally of the chain 26, the sprocket 24 and chuck will move longitudinally of the chain, then pivot about the corner of the sprocket 24. As the chain will not defleet to accommodate this pivotal movement, the axis of the sprocket will move laterally. After the pivotal movement has been completed and the next succeeding side of the sprocket 24 is in engagement with the chain, the sprocket will once again move longitudinally and the cycle is repeated. This movement is shown in FIG. 17. However, by withdrawing the backing bar 49 from chain 26, the pivotal movement of the sprocket 24 and chuck 2 will cause the chain 26 to be deflected inwardly so that the shaft 13 and chuck 2 do not move laterally during the pivotal movement. Thus, for example, if simple rotary movement of the chuck about the axis of shaft 13 is desired, this can be accomplished by restraining the lateral and longitudinal movement of the shaft and releasing bar 49. With the shaft restrained in both lateral and longitudinal movement, the pivotal action of the,

chuck will be taken up by a deflection of chain 26. This is shown in FIG. 18. Similarly, other motions of the chuck can be provided by restraining either the lateral or longitudinal movement of the shaft 13 and correspondingly releasing or applying the back bar 49 to the chain.

To restrain movement of shaft 13 and chuck 2 in a direction longitudinal of chain travel,

arms

62 and 63 are disposed on either side of shaft 13.

Arms

62 and 63 are adapted to open and close, and, when in the opened position, permit free movement of shaft 13 in the direction of chain travel. In the closed position the

arms

62 and 63 prevent movement of shaft 13 in the direction of chain travel but permit free movement of the shaft and the chuck 2- laterally of the direction of chain travel.

The outer end of each of the

arms

62 and 63 is pivotally connected to the triangular plate 11 by pin 64, and the ends of the arms are connected together by a pair of links 65.

To open and close the arms, a ram or piston rod 66 of a fluid cylinder 67 is connected by link 68 to the arm 63 inwardly of the position of pivotal attachment to plate 11. The outer end of cylinder 67 is pivotally connected to a bracket 69 secured to side wall 9.

With this construction, an extension of ram 66 from cylinder 67 closes the arms and brings them into engagement with a bearing 70 secured to the shaft 13, while a retraction of ram 66 opens the arms and permits free movement of the shaft 13 and chuck 2 in the direction of chain travel.

To restrain the shaft 13 and chuck 2 in lateral movement with respect to chain 26, a block 71 is slidably disposed on arm 63. The ram 72 of a fluid cylinder 73 is connected to block 71, and the outer end of cylinder 73 is pivotally attached to the end of arm 63. When ram 72 is extended, the block 71 is moved inwardly into engagement with hearing 70 on shaft 13. With block 71 in engagement with bearing 70, the shaft 13 will be prevented from moving laterally with respect to the chain 26.

As the chuck 2 is traveling through its series of paths of movement, the series of

heads

4, 5, 6 and 7, which are mounted on drum 8 and carry abrading or polishing members, are successively rotated to a position over the chuck and lowered into contact with the workpiece to polish a particular portion of the workpiece.

The drum 8 is supported for rotation on a central post 78 which is mounted on the base housing. The lower end of post 78 is welded to ring 79. The ring 79 is secured to plate 89 by bolts 81 and the plate 80 is secured to the upper triangular plate 11.

The lower end of drum 8 is attached to a post housing 82 which is disposed concentrically around the lower portion of post '78. The post housing 82 and drum 8 are adapted to rotate around the post 78 to successively position the heads over the chuck 2.

To mount the post housing 82 for rotation, the lower portion of the housing is enlarged in diameter, as indicated by 83, and defines a recess to house bearings 84. The bearing 84 are retained within the recess by a retaining ring 85 which rests on a shoulder 86 formed on the outer surface of the post. The bearings 84 serve to take up the thrust of the rotating post housing 82 as well as journaling the housing for rotation on the post 73.

To rotate the drum 8 and post housing 82, an index disc 87 is secured to the lower edge of the post housing. The index disc, shown in FIG. 2, is provided with four notches 88 in the periphery and which are disposed at the cardinal points of the disc. The notches 88 are adapted to be engaged by a pawl 89 and movement of the pawl 89 while engaged with the notch rotates the indexing disc 87, post housing 82 and drum 8.

The pawl 89 is pivotally connected to an indexing plate 90 and the inner edge of the indexing plate is secured to a split bearing 91 which is secured around the post 78 to permit rotational movement of the plate around the post.

The pawl 89 is inserted within the notches 88 and withdrawn therefrom by an air cylinder 92. The inner end of cylinder 92 is secured to a bracket 93 which is mounted on the indexing plate 90. The air cylinder 92 carries a ram or piston rod 94 and the inner end of the rod is attached to the outer end of the pawl 89.

To oscillate the pawl 89 about the axis of post 78, the indexing plate 90 is pivotally connected to the peripheral edge portion of a crank plate 95 by a connecting rod 96. The crank plate 95 is rotated about its axis by a motor 97 which is suitably secured to the outer surface of side wall 1. The drive shaft 98 of motor 97 carries a pulley 99 and a belt 100 is connected between pulley 99 and pulley 101 mounted on the drive shaft of a worm drive 102. Rotation of the worm drive is transmitted through gear box 103 to the crank plate shaft to rotate crank plate 95.

Rotation of crank plate 95 provides the indexing plate 98 and pawl 89 with a generally oscillating motion about the axis of post 78. If the pawl 89 is engaged within the notch 88, the oscillating motion of the pawl will rotate the post housing 82. However, if the pawl is not engaged within the notch the pawl will ride freely on the outer periphery of the indexing disc 87 and will not rotate the post housing 82.

To lock the indexing disc 87 and prevent rotation thereof and corresponding rotation of post housing 82 and drum 8, a lock pin 104 is disposed to engage the notches 88 in the indexing drum. The pin 104 is mounted for sliding movement within a bearing 105 which is supported by a bracket 106. An air cylinder 107 is also supported by bracket 106 and carries a piston rod 108 which is attached to the outer end of pin 104. With this construction, a retraction of piston rod 108 results in the lock pin 104 being moved out of engagement with the notch 88 so that the index disc 87 is free to rotate.

Each of the

heads

4, 5, 6 and 7 which are connected to the drum 8 includes an abrasive wheel or belt which is adapted to polish or finished a particular portion of the workpiece. The drum 8 is rotated to successively position each head directly above the workpiece, the head is subsequently lowered to bring the abrasive member into contact with the workpiece and raised after the polishing operation is completed and the drum is subsequently rotated to bring the next succeeding head into position over the workpiece.

The connection between the drum 8 and post housing 82 is accomplished by bolts 110 which secure the lower end of drum 8 to the upper outwardly extending flange 111 of the post housing. The drum 8 and housing 82 then are connected integrally so that they rotate together around the post 78.

The upper end of drum 8 is journalled for rotation by a bearing assembly 112. The flange 113 of a bearing assembly 112 is secured to the upper end of the drum 8 by suitable bolts and the bearing serves to journal the drum for rotation on the post 78.

To permit vertical movement of each head with respect to drum 8, a ring 114 is secured to the upper edge of the drum and a series of guides 115, one for each of the heads, are suspended from the ring 114 at cardinal positions. Each guide 115 is slidably received within a guide way 116 which is secured to the respective heads so that the heads may move vertically with respect to the chuck and workpiece.

Each of the

heads

4, 5, 6 and 7 includes a frame 117 which carries the abrading or polishing member. The polishing members may all be of similar construction or may be different types depending on the particular polishing action to be provided by that member. The head frames 117 include a pair of upper arms 118 which are connected to the upper end portions of the corresponding guide ways 116. A pair of vertical depending arms 119 are pivotally connected to each upper arm 118 adjacent the guide way 116. In addition, a pair of outer depending arms 120 are pivotally connected to each upper arm 118 at the outer end thereof. The lower ends of the

arms

119 and 120 are connected by bottom arms 121 to provide a generally square frame structure. With this construction, the

arms

119, 120 and 121 can swing back and forth radially with respect to the post 78 while the arms 118 are fixed with respect to movement in that direction. However, the entire head frame 117, being connected to guide way 116, can move vertically with respect to the drum 8.

The abrading members are mounted for adjustable pivotal movement on the respective head frames 117. However, as the abrading or polishing members on each head are of somewhat different structure, the attachment of the polishing member to the head frame varies with each head. In regard to head 7, a shaft 122 is rotatably secured between lower arms 121 by means of studs 123 which are journalled within suitable openings in each of the arms 121 and are threadedly engaged with the ends of the shaft 122. A pair of brackets 124 are secured in spaced relation to shaft 122 and the brackets 124 carry a channel shaped support 125. The lower flange of channel support 125 supports a bearing 126 which receives a wheel shaft 127. The upper end of shaft 127 is also journaled within a bearing 128 carried by the upper flange of support 125.

The lower end of wheel shaft 127 carries a wheel 129 having an abrasive covering or an abrasive surface. The lower edges of the wheel, indicated by 131 in FIG. 2, are rounded to the curvature of the corner of the workpiece. This wheel configuration permits the wheel 129 to polish the corner of the workpiece and also the portion of the bottom of the workpiece adjacent the corner.

The polishing wheel 129 is driven by a motor 131 mounted on support 132 which is attached to brackets 124. A drive shaft 133 of the motor carries a pulley 134 which drives a pulley 135 through a belt 136. The pulley 135 is suitably secured to the wheel shaft 127.

To vary the grinding or polishing angle of the wheel 129 to accommodate different side wall contours in the workpiece, a stud 137 is secured to a shaft 138 which is journaled between the upper ends of the brackets 124. A pair of pedestals 139 extend upwardly from the arms 121 and each of the pedestals 139 supports a block 140 having a series of holes 141 therein. To attach the pedestals 139 to the stud 137, a rod 142 is connected between the blocks by studs which extend through holes 141 and are threadedly engaged within openings in ends of the rod. The rod 142 carries a block 143 having an opening which receives the stud 137, and the stud 137 is removably secured within the opening by nuts 144.

By changing the position of attachment of rod 142 to the block 140 by selection of the proper holes 141, the brackets 124 can be pivoted around shaft 122 to thereby pivot the polishing wheel 129. This permits the angle of grinding to be changed for any particular grinding operation.

The head 6 carries an abrading member adapted t abrade or polish the inner side wall surface of the workpiece 3. As best shown in FIG. 2, a pair of bars 45 are pivotally connected by pins 146 to the arms 121 of the frame 117, and a pair of cross bars 147 connect the bars 145 together to provide an integral structure pivotally attached to frame 117.

A pair of supporting braces 148 are secured to cross bars 147 and the inner ends of the braces 148 carry a bearing bracket 149 which houses a bearing 150. The bearing 150 journals a roller shaft 151 which carries a roller 152 and an endless polishing belt 153 is driven by the roller.

The drive for roller 152 is provided by a motor 154 secured to a support. bracket 155 which is welded to 8 the outer ends of braces 148. The drive shaft 156 of motor 154 carries a pulley 157 which drives pulley 158 on roller shaft 151 through an endless belt 159.

The polishing belt 153 travels over a series of rollers journaled on a framework 160 which is secured to the support bracket 155. As shown in FIG. 13, the belt 153, after passing over the polishing roller 152, extends over roller 161 rotatably attached to the lower portion of framework 160, then over upper roller 162 and finally over lower roller 163 to polishing roller 152.

To provide the proper tension on belt 153, a suitable belt tensioning device is employed. As shown in FIG. 13, the belt 153, after leaving upper roller 162, extends around a fixed roller 164 and a spring biased roller 165. Roller 165 is slidably mounted on framework 160 and a spring 166 is connected between the roller bearing bracket 167 and a fixed pin 168. The force of spring 166 urges roller 165 downwardly and keeps a fixed degree of tension on belt 153.

As the supporting structure for the polishing belt 153 and roller 152 is pivotally attached to head frame 117, the roller 152 can be pivoted about pins 146 with respect to the frame 117 and with respect to the workpiece 3 to accommodate changes in slope of the inner side wall surface of the workpiece or pan.

The frame 117 and roller 152 can be locked at any desired angle by means of the stud 137, block 143 and rod 142. In the case of head 6, the outer end of stud 137 is pivotally attached to lugs 169 on framework 160 rather than being attached to brackets 124 as in the case of head 7. However, with head 6, the adjustable attachment of the stud 137 to the blocks 140 on pedestals 139 is identical with that of head 7.

The head 4 carries a polishing member adapted to polish the bottom surface of the workpiece or pan. In head 4, a control support is secured to the

arms

118 and 121 and carries an endless polishing belt. The central support includes a pair of bars 170 which extend between the

arms

118 and 121 respectively and are connected together by a plate 171. The lower bar is connected to the arms 121 by a pair of studs which extend through openings in the arms 121 and are threaded y engaged within openings in the ends of lower bars 170.

To provide a small degree of adjustment a slotted bracket 172 is attached to each end of upper bar and a stud is secured within the slot in bracket 172 and within an aligned opening in the respective arm 118. This slotted connection permits a small amount of pivotal movement or adjustment of the central support.

A grinding roller 173 is journaled within a bracket 174 secured to the lower end of plate 171 and carries the wide belt 175 which is adapted to contact the bottom surface of the workpiece to polish the same. The corners of roller 173 may be rounded to complement the corners of the workpiece.

The belt 175 is driven by a motor 176 mounted on a plate 177 which in turn is secured to the upper end of plate 171. The drive shaft of motor 176 carries the roller 173 and drives the same to move the belt.

The

rollers

179 and 180 are tensioning rollers similar to

rollers

164 and 165 of head 6. The roller 179 is journaled in fixed relation to plate 171, while roller 180 is biased downwardly to thereby maintain the proper tension on the belt 175.

The head 5 is similar to head 7 and carries a polishing roller or wheel 181, similar to wheel 129. However, wheel 181 is adapted to polish the upper portion of the side wall of the workpiece as well as the upper edge thereof.

To move the frame 117 and abrading member, such as the grinding wheel 129, radially inward toward the inner side wall of the workpiece, an air cylinder 182 is suitably secured between a pair of depending arms 183 which are attached to ends of guide way 116 and extend downwardly therefrom. A piston rod 134 is slidably disposed within cylinder 182 and extends through a suitable opening in bearing 185 and the bearing in turn is secured to the pedestals 139. To cushion the movement of the head frame, a pair of springs 186 are disposed on the piston rod 184 on either side of the bearing 185. Suitable spring stops 187 are threaded onto the rod 184 and the springs are interposed between the bearing 185 and the respective stops 187. The resilient connection provided by springs 186 allows the lower portion of head frame 117, namely the

arms

119, 120' and 121 to float radially with respect to the axis of post 78. This floating action allows for variation in the wall thickness of the workpiece against which the grinding wheel 129 or other polishing member is operating. As the grinding wheel 129 moves along the surface of the side wall of the workpiece, the wheel is biased toward the side wall and yet is permitted to move inwardly and outwardly with variations in wall thickness due to the resilient connection between the piston rod 184 and the head frame 117.

As previously described, the post housing 82, drum 8 and attached

heads

4, 5, 6 and 7 rotate about the post 73 and each head is successively positioned and indexed over the workpiece disposed on chuck 2. To lower the head disposed over the chuck 2, an air cylinder 188 is secured to post 78 and carries a piston rod 189 which extends downwardly therefrom. The lower end rod 189 carries an adjustable pad 190'.

The pad 190 is disposed to engage the undersurface of a foot 191 which extends inwardly from the arms 183 of each of the head frames. By extending the piston rod 139, the head is lowered and when the piston rod is contracted the pad 1911, being in engagement with foot 191, will raise the head upwardly.

The lower end of drum 8 is provided with suitable notches at the locations of the heads to permit the downward movement of the rod 189.

The heads are supported during rotation around post 73 by the sliding contact of feet 191 on ring 192. The ring 192 is supported on a suitable shoulder 193 formed on post 78 and is maintained in position on post 78 by a ring lock 194. As the heads are rotated about the post 78 the feet 1911 slide on the ring 192 to support the heads.

To permit the head which is positioned over the chuck 16 to be lowered downwardly toward the chuck, a recess 195 is provided in ring 192. The recess 195 is disposed in radial alignment with the axis of the cam follower 22. When the piston rod 139 is fully contracted, the pad 190 is brought into engagement with the recess 195. The pad 190 and recess 195 have complementary tapered surfaces so that there is a wedging engagement between the pad and the recess. In this position, the lower end of the piston rod 189 is disposed above the lower end of the drum 8 so that the drum is free to rotate without interference with the piston rod. Furthermore, the top of the pad 190 is disposed generally flush with the upper surface of ring 192 so that the heads can be rotated and the next succeeding foot 191 can slide over the upper surface of the ring 192 to a position in alignment with the recess 195.

When the piston rod 189 is extended the pad 199 is moved downwardly out of engagement with the recess 195 and the head correspondingly is lowered to a position where the grinding wheel 129 or other polishing member will engage the workpiece. After the polishing or finishing operation is completed the head is moved upwardly by retraction of the piston rod 189.

Electrical energy is supplied to the apparatus through brushes 196 which engage collector rings 197 mounted on hollow post 198. Electrical leads, not shown, are connected to collector rings 197 and extend downwardly through post 78 to the locations of use. Similarly, suitable lines for supplying air and oil to the apparatus may be disposed within post 198 and extend within post 78 to the location of use.

The rotation of the heads, lowering and raising of the heads and chuck movement are controlled through an electrical system, as shown in FIGS. 21 and 22.

In the electrical control diagram the main power lines are indicated by 199 and horizontal branch lines connected across the power lines are designated by an L series of numbers, such as L1, L2, etc. The contacts actuated by a given relay are designated by the reference number of the relay and a hyphenated number.

To begin operation of the polishing apparatus, the automatic cycle normally starts with all of the

heads

4, 5, 6 and 7 in the raised position with the head 4 disposed approximately 45 counterclockwise of a position directly over chuck 2. In this 45 position the normally closed limit switch 201) in L12 is held open by the engagement of the switch by a projection 291 on index disc 87.

To set up the automatic cycle, push button 2112 in L9 is actuated to energize main control relay 203. The light 204 indicates the control power is on. The mercoid vacown control switch 205 and pressure control switch 206 in L9 are closed if vacuum and pressure conditions are proper. Relay 203 is locked in by closing of contacts 203-1 in L10. Energizing relay 203 also closes contacts 203-2 and 203-3 in power lines 199.

At this time, the drive for the polishing members such as wheels 129 and 1.81 and

belts

153 and 175 may be started by actuating

push buttons

207, 203, 209 and 210 in L1, L3, L5 and L7, respectively. Depressing push button 207 energizes motor relay 211 which is in series with the normally closed manual reset overload contacts 212. Motor relay 211 is locked in by closing of contacts 211-1 in L2.

Similarly, actuation of

push buttons

298, 209 and 210 energize

motor relays

213, 214, and 215 in L3, L5 and L7, respectively, which are in series with normally closed overload contacts 216, 21.7 and 218, respectively. The motor relays 213, 214 and 215 are locked in by closing of contacts 213-1, 214-1 and 215-1, respectively.

Energizing motor relay 211 serves to start motor 131 to drive polishing wheel 129, while energizing motor relay 213 serves to start motor 154 to drive belt 153. Similarly, energizing motor relays 2.14 and 215 start motors 176 and 219, respectively, to drive belt 175 and wheel 181.

A normally closed emergency stop button 220 is provided in L1 to stop the motors and the automatic cycle, if necessary.

To begin the automatic cycle, the start-cycle push button 221 in L11 is depressed thereby energizing control relay 222, and closing contacts 222-1 in L12, 222-2 in L13. 222-3 in L20, 222-4 in L25, 222-5 in L27 and 222- 6 in L31. Closing of contacts 222-6 in L31 latches mechanically held relay 223 in L32 due to the fact that limit switch 200 in L31 is closed at the start of the cycle.

Energizing of relay 223 closes load contacts 223-1 in L34 to energize

solenoids

224 and 225. Solenoid 224 actuates cylinder 59 to move backing bar 49 out of engagement with chain 26, and solenoid 225 actuates cylinder 67 to close the

arms

62 and 63. This sets up the chuck mechanism for circular and lateral movement of the chuck but prevents longitudinal movement of the chuck with respect to the direction of travel of chain 26.

Energizing relay 223 also opens contacts 223-1 in L26 and 223-2 and L31 and closes contacts 223-3 in L33.

Simultaneously, with the above action, index motor relay 226 in L13 is energized to start index motor 97 due to the fact that normally open switch 227 in L13 is closed because lock pin 104 is out of engagement with notch 88. Switch 227 is in multiple with normally closed limit switch 228 in L14 which is open at the start of operation. Switch 228 is actuated by a collar 229 secured to crank plate and functions when actuated to keep index motor relay 226 in L13 energized after switch 227 opens or resets.

Energizing motor relay 226 starts the index motor caus- 11 ing pawl 89 to engage one of the notches 88 in index disc 87 and thereby rotate the heads.

As the index drum rotates, the lock pin 104, which is spring loaded, rides on the edge of the index disc and is free to position itself in the next notch 88. At this time, the lock pin solenoid 238 in L19 is energized because switch 231 in L19 is closed. Lock pin solenoid 230 actuates cylinder 197 to withdraw pin 184 from the notch. Switch 231 rides on collar 229 and is open when the crank plate 95 rotates.

When lock pin 194 drops into the next notch as index disc 87 rotates, switch 227 in L13 is actuated by a projection on the pin and opened while the normally closed switch 227A in L16 closes. Closing of switch 227A in L16 energizes relay 232 and also energizes index pawl solenoid 233 in L17, as the contacts 226-1 and 226-2 in L17 and L18 respectively are closed when the index motor relay 226 is energized.

The energization relay 232 closes contacts 232-1 in L25 and opens contacts 232-2 in L38.

Energizing index pawl solenoid 233 operates cylinder 92 to pull the index pawl 89 out of the drive notch 88 and this action stops rotation of the drum 8 with head 4 then being disposed directly above the chuck 2 and workpiece 3.

The index motor 97 is then under control of switch 228 in L14 which is closed as the crank plate 95 began rotation. The index motor 97 continues to operate, moving pawl 89 clockwise about post 73, until switch 228 is opened by riding off the collar 229 on crank plate 95. The opening of switch 228 stops index motor 97 and at this time pawl 89 is positioned immediately adjacent the next succeeding drive notch 88.

Simultaneously, with energizing index pawl solenoid 233 to pull pawl 89 out of the drive notch, the closing of switch 227A in L16 energizes relay 234 in L22 and opens contacts 234-1 in L19, opens contacts 234-2 in L24, closes contacts 234-3 in L25, closes contacts 234-4 in L27 and opens contacts 234-5 in L33.

The closing of

arms

62 and 63 through energizing of solenoid 225, closes switch 235 in L36 thereby energizing relay 236. Energizing relay 236 closes contacts 236-1 in L25.

Thus, closing contacts 234-3 in L25, in combination with the previously closed contacts 222-4, 232-1 and 236-1, energizes solenoid 237 to operate cylinder 188 to lower head 4 toward the workpiece.

To assure that head 4, which is positioned above chuck 2, will not lower until lock pin 104 is in engagement with notch 88 and that the

arms

62 and 63 are closed, relay 232 must be energized and contacts 232-1 in L25 closed before the solenoid 237 is energized.

The normally closed contacts 223-1 in L26 are in multiple with contacts 236-1, and contacts 223-1 are open during operation of heads 4 and 5 and closed for the operation of the third and fourth heads 6 and 7. As the

arms

62 and 63 are not closed during operation of the third and fourth heads, the heads will be lowered without the need for energizing relay 236 and closing of contacts 236-1.

Head 4 is lowered by cylinder 188 and as pad 190 is lowered out of recess 195 switch 238 in L20 is opened and to energize chuck motor relay 239, thereby starting chuck motor 29 and closing contacts 239-1 in L27. Also, as the chuck begins to rotate, the head 4 engages and closes switch 240, thereby energizing solenoid 241 in L27 to actuate cylinder 182 and move the grinding roller 171 toward the side wall of the workpiece 3. In addition, suitable oil spray solenoids, not shown, may be located in L27 to operate oil sprays for the polishing operation.

The function of contacts 239-1 in L27 is to release pressure of roller 171, should the chuck motor stop, for excessive metal would be removed with the chuck stalled and pressure on the polishing wheel.

The contacts 234-4 in L27 are closed when relay 234 is transferred to the lower head position, as previously described, and later as the head is raised, relay 234 opens providing fast release of the pressure on roller 171 even though switch 240 is still closed.

Closing of switch 240 also seals in relay 242 in L35 and the function of relay 242 will follow. Energizing relay 242 opens contacts 242-1 in L37 and closes contacts 242-2 in L38.

As previously described, chuck drive motor 29 is operating and the chuck 2 is rotating as well as moving laterally of the direction of travel of chain 26, as shown in FIG. 18. This is due to the

arms

62 and 63 being closed and preventing longitudinal movement of the chuck. However, the block 71 is not in engagement with the chuck shaft bearing 70 so that the chuck is free to float laterally to accommodate the pivotal movement of the sprocket 24 and chuck 2 about the corners thereof. This chuck motion serves to polish the bottom surface and the corners of the workpiece After the fifth turn or quarter revolution of chuck 2, switch 243 in L37 is actuated and closed. This is accomplished by securing a sprocket 244 on the lower end of chuck shaft 13 and sprocket 244 meshes with a second sprocket 245 mounted on arm 15. The

sprockets

244 and 245 are provided with a tooth ratio of 4 to 5 with sprocket 244 having the lesser number of teeth and thereby rotating 5 revolutions to 4 revolutions of sprocket 245.

Sprocket 245 carries a pin 246 which engages switch 243 and with the gearing ratio between

sprockets

244 and 245, switch 243 is momentarily actuated after one and one-quarter revolutions of shaft 13.

Closing of switch 243 in L37 provides a Ledex rotary solenoid 247 with one impulse thereby rotating

pointers

248 and 249 of the selector step switch one step. This one step movement of pointer 249 energizes solenoid 250 in L38, as contacts 242-2 have previously been closed, to actuate cylinder 73 and move block 71 into engagement with hearing 70 on shaft 13.

The chuck continues to rotate and with longitudinal movement in the direction of chain travel prevented by the

closed arms

62 and 63 and with lateral movement of the shaft 13 prevented by block 71, the chuck 2 will merely rotate about its central axis. This simple rotary movement results in belt polishing the bottom surface of the workpiece except for the four corner portions.

At the tenth turn or quarter revolution of chuck 2, switch 243 is again momentarily actuated to provide the Ledex solenoid 247 with a second impulse to move the pointers 248 and 249 a second step. This second step trips relay 234 through the closed trip contacts 234-6 in L21 and thereby closes contacts 234-2 in L24 to encrgize solenoid 251. Energizing solenoid 251 actuates cylinder 188 to raise the head 4.

With the operation of the first head 4, in the polishing cycle, two impulses of the Ledex solenoid are required to raise the head, as contacts 242-1 in L37 are open. However, with the operation of the second, third and fourth heads, contacts 242-1 are closed and thus only one impulse of the Ledex solenoid is necessary to trip relay 234 and energize solenoid 251. Therefore, the first head 4 acts on the workpiece for 10 quarter revolutions or turns of the chuck and the remaining heads act on the workpiece for only 5 quarter revolutions of the chuck. In the case of the first head, during the first 5 quarter revolutions or turns, the chuck has one motion and has a second purely rotary motion during the remaining five turns.

With relay 234 now tripped and raise-head solenoid 251 energized, contacts 234-4 and L27 are opened to deenergize contact pressure solenoid 241.

As the head raises, switch 240 in L27 opens thereby deenergizing relay 242 and closing contacts 242-1 and opening contacts 242-2. Opening contacts 242-1 de-energizes 13 solenoid 250 to withdraw block 71 from the shaft bearing 70.

Also as the head raises, switch 238 in L20 is opened to de-energize chuck motor relay 239 and stop the chuck motor. De-energizing relay 239 opens contacts 239-1 in L27.

As the head reaches its maximum position in upward travel, it closes switch 252 carried by ring 114 in L19, which was opened when the head was lowered, to energiz lock pin solenoid 230 through

closed switches

253, 254, 255 and 231 and the closed contacts 234-1. Solenoid 230 actuates cylinder 107 to pull lock pin 104 out of the notch 88 and this outward movement of lock pin 104 actuates switch 227 in L13 to close the same and energize index motor relay 226 to start the index motor 97.

Closing switch 227 opens switch 227A in L16 to deenergize relay 232 and close contacts 232-2 in L38. Closing of contacts 232-2 in series with the closed homing contacts 247-1 resets the Ledex solenoid and brings

pointers

248 and 249 back to their original setting.

The lock pin solenoid 230 in L19 remains energized as long as switch 231 is closed by contact with the switch actuator 229. This duration of contact of switch 231 and actuator 229 is sutficient to permit the lock pin 104 to clear the notch 88 as the index disc 87 is rotated by the motor 97. Switch 231 then opens to de-energize lock pin solenoid 230, releasing lock pin 104 so that the spring loaded pin can ride on the periphery of index disc 87.

As the index disc 87 rotates, the second head 5 thereby moves to a position directly over chuck 2 and the lock pin 104 falls into the next succeeding notch 88 to lock the second head in this position over chuck 2. When lock pin 104 falls in notch 88, switch 227 opens and switch 227A in L16 closes, as in the case of the first head, to seal in relay 232, energize relay 234 through the closed contacts 226-1 in L17 and 234-7 in L23, and energize solenoid 233 to withdraw index pawl 89 from the drive notch 88.

As the

arms

62 and 63 are closed, switch 235 is closed energizing relay 236 in L36 and closing contacts 236-1 in L25. As contacts 222-4, 234-3, 232-1 and 236-1 in L25 are closed solenoid 237 is energized to lower the head toward the chuck.

As the second head 5 lowers, switch 238 is closed, starting chuck motor 29 through motor relay 239 as in the case of the first head operation. Downward movement of the head also closes switch 256 in L28 energizing solenoid 257 to actuate cylinder 188 of the second head and provide contact pressure against the side wall of the workpiece. In addition, switch 256A in L33 is closed when the second head is lowered.

As the

arms

62 and 63 are closed, but block 71 is withdrawn, the chuck is free to move laterally of the chain as well as rotate. As the chuck 2 travels in its path of movement, switch 243 is again momentarily actuated after the fifth chuck turn to provide an impulse to Ledex solenoid 247 and move

pointers

248 and 249 one step. As relay 242 in L35 is not sealed in due to switch 240 being open, contacts 242-1 in L37 are closed, and the one step advance of pointer 248 trips mechanically held relay 234 to thereby energize the raise head solenoid 251 in L24.

Also, as relay 242 is not sealed in, solenoid 250 which actuates cylinder 73 to move block 71 toward shaft 13, is not energized, thereby permitting lateral movement of the chuck with respect to chain 26.

As the second head 5 raises, the chuck motion stops as switch 238 is opened. Before switch 256 is reset by raising of the second head, the closed switch 256A in L33 in series with contacts 234-5, which are now closed due to switch 243 tripping relay 234, and closed contacts 223-3 trips mechanically held relay 223 to open contacts 223-4 in L34 and de-energize

solenoids

224 and 225. The deenergizing of

solenoids

224 and 225 moves hacking bar 49 toward chain 26 and opens

arms

62 and 63 to set the chuck mechanism for the third and fourthheads.

When the second head 5 reaches its maximum upward travel, switch 253 in L19 is closed and lock pin solenoid 230 is again energized to initiate index drive motion as previously described.

The drum 8 is then rotated to position the third head 6 over chuck 2 and with the lock pin 104 engaged with the next notch 88 the head 6 is lowered and the polishing cycle is repeated. As the third head is lowered, switch 258 in L29 is actuated to energize solenoid 259 and actuate contact pressure cylinder 188.

The polishing cycle of the third head is shown in FIG. 17. In this motion the chuck 2 moves longitudinally of the chain due to the open condition of

arms

62 and 63, then pivots around its corners as the cam follower 22 moves into the corner of cam 21, with the shaft 13of the chuck moving laterally of the chain to accommodate the pivotal movement. This motion is repeated for 5 sides or quarter revolutions of the chuck.

The third head is then raised, in a manner similar to that described with the first two heads, and switch 254 is closed to again initiate the index motor mechanism to rotate the drum 8 and position the fourth head 7 over the chuck. The fourth head is lowered, closing switch 260 and energizing solenoid 261 to provide contact pressure, similar to the action provided by switch 258 with the third head, and the polishing cycle is repeated with the same chuck movement as was used with the third head to complete the polishing or finishing operation.

Raising of the fourth head closes switch 255 in L19, again starting index drive motor to rotate the index disc 87 and heads to a position where switch 200 is actuated. Opening of switch 200 in L12 tie-energizes relay 222 and stops all action. This stoppage occurs with the first head approximately 45 from a position directly over chuck 2. This 45 position of the heads permits convenient loading and unloading of the workpiece on the chuck.

While the above description is directed to an automatic operation for finishing the workpiece, it is contemplated that all or any portion of the operation cycle may be controlled manually in place of the automatic operation.

Similarly, while th description has been directed to the use of the four heads with a particular type of abraiding or polishing member associated with each head, it is contemplated that any desired number of heads may be employed on the drum 8 and the abrading members may be varied to meet the particular grinding or polishing operations to be accomplished.

The present invention provides an automatic apparatus for polishing the entire inside surface of a pan or similar workpiece in an automatic sequential operation. The workpiece or ware is merely placed on the chuck and through a series of automatic operations, heretofore described, the entire inside surface of the workpiece, including the side walls and the corners, are completely finished in a single operation.

The apparatus can be used to finish any type of workpiece having any desired shape. For example, the workpiece may be oval, round, triangular or the like in place of the square workpiece described above. In order to finish the irregular workpiece, the only requirement is that the cam 21 and sprocket 24 be provided with the same configuration as the workpiece to be finished.

It is also contemplated that any one of the three movements can be performed separately for a particular polishing operation rather than in the sequence as described. In this situation, the machine may have a single head which can be raised or lowered toward the workpiece which in turn may be given one or a series of different movements.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

I claim:

1. An automatic abrading apparatus for finishing a workpiece, comprising, chuck means mounted for universal movement in a given plane, a flexible endless drive member, a driven member connected to said chuck means and disposed in engagement with said drive member, cam means associated with said chuck means to provide a given path of movement for said chuck means as the driven member is driven by said driving member, said driven member and said cam means both having a peripheral configuration substantially similar to that of the workpiece to be finished, an abrading member adapted to engage the workpiece and finish the same as the chuck moves in said path of movement, and means for moving said abrading member toward the chuck to effect engagement of said abrading member with the workpiece and for moving said abrading member away from the chuck after termination of said finishing operation.

2. An automatic abrading apparatus for finishing a workpiece, comprising, chuck means mounted for universal movement in a given plane, a flexible endless drive member, a driven member connected to said chuck means and disposed in engagement with said drive member, cam means associated with said chuck means to provide a given path of movement for said chuck means as the driven member is driven by said driving member, said driven member and said cam means both having a pcripheral configuration substantially similar to that of the workpiece to be finished, means for selectively preventing movement of said chuck means in a direction parallel to the direction of travel of said endless drive member, and an abrading member disposed in alignment with said chuck means and adapted to engage said workpiece as the chuck means moves in said path of movement.

3. An automatic abrading apparatus for finishing a workpiece, comprising, chuck means mounted for universal movement in a given plane, an endless drive member, a driven member connected to said chuck means and disposed in engagement with said drive member, cam means associated with said chuck means to provide a given path of movement for said chuck means as the driven member is driven by said driving member, said driven member and said cam means both having a peripheral configuration substantially similar to that of the workpiece to be finished, first holding means for selectively preventing movement of said chuck means in a direction parallel to the longitudinal dimension of said endless drive member, second holding means for selectively preventing movement of said chuck means in a direction normal to the longitudinal dimension of said endless drive member, and an abrading member disposed in alignment with said chuck means and adapted to engage said workpiece as the chuck means moves in said path of movement.

4. An automatic abrading apparatus for finishing a polygonal shaped workpiece, comprising, a supporting structure, chuck means mounted on said supporting struo ture for universal movement in a given plane, a flexible endless drive member, a driven member connected to said chuck means and disposed in engagement with said drive member, a cam member associated with said chuck means and disposed in axial alignment with said driven mem ber, said driven member and said cam member both having a peripheral configuration substantially similar to that of the workpiece to be finished, a cam follower connected to said supporting structure and disposed to ride on said cam member as said chuck means is driven by said drive member and thereby provide said chuck means with a given path of movement whereby a side of the driven member and the corresponding side of the Workpiece are moved parallel to the direction of travel of the endless drive member and subsequently rotated about a corner thereof to bring the next succeeding side in parallel alignment with said direction of travel of the endless drive member, an abrading member disposed in alignment with said cam follower and adapted to engage and finish the workpiece, and means for moving said abrading i6 member toward the chuck to effect engagement of said abrading member with the workpiece and for moving said abrading member away from the chuck after termination of said finishing operation,

5. An automatic abrading apparatus for finishing a polygonal shaped workpiece, comprising, a supporting structure, chuck means mounted on said supporting structure for universal movement in a given plane, an endless drive member, a driven member connected to said chuck means and disposed in engagement with said drive memher, a cam member associated with said chuck means and disposed in axial alignment with said driven member, said driven member and said cam means both having a peripheral configuration substantially similar to that of the workpiece to be finished, a cam follower connected to said supporting structure and disposed to ride on same cam member as said chuck means is driven by drive member and thereby provide said chuck means with a given path of movement whereby a side of the driven member and the corresponding side of the workpiece are moved parallel to the longitudinal dimension of the endless drive member and subsequently rotated about a corner thereof to bring the next succeeding side in parallel alignment with said longitudinal dimension of the endless drive member, means for preventing deflection of the endless drive member as the driven member is pivoted about a corner thereof to thereby effect a lateral movement of the axis of the driven member and said workpiece with respect to the longitudinal dimension of the endless drive member during the pivotal movement of said driven member, and an abrading member disposed in axial alignment with said cam follower and adapted to engage said workpiece as the chuck means moves in said path of movement.

6. An automatic abrading apparatus for finishing a polygonal workpiece, comprising, chuck means mounted for universal movement in a given plane, a drive sprocket, an idler sprocket, an endless chain connecting said sprockets, means for biasing said idler sprocket away from said drive sprocket to provide tension on the chain and permit deflection of the chain, a polygonal sprocket secured to said chuck means and disposed in engagement with said chain, polygonal cam means associated with said chuck means for moving said chuck means in a path of movement as the polygonal sprocket is driven by said chain, said cam means and said polygonal sprocket and said workpiece having substantially the same polygonal configuration and size, said path of movement including movement of a side of the polygonal sprocket and the corresponding side of the workpiece parallel to the direction of chain travel and a subsequent pivotal movement of the polygonal sprocket about a corner thereof to position the next succeeding side thereof in parallel relation with said direction of chain travel, said chain being prevented from deflecting by the pivotal movement of said polygonal sprocket to thereby move the lateral position of the axis of said chuck means with respect to the direction of chain travel, and an abrading member disposed outwardly of the chuck means and adapted to engage the workpiece and abrade the same during movement of said chuck means.

7. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece, comprising a supporting structure, chuck means mounted on said supporting structure and adapted to support the workpiece, drive means for moving said chuck means in a given linear path of movement, a support column secured to the supporting structure, a series of heads disposed in circularly spaced relation to said column and each of said heads having an abrading member, means for slidably mounting each of said heads on said column to permit vertical movement of the heads with respect to the column, means for rotating said heads around the column to successivel-y position each of the heads over said chuck means, and means for lowering the head positioned over the chuck 17 means toward said chuck means to effect engagement of said abrading member with the workpiece and for raising the head away from the chuck means after termination of said polishing operation.

8. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece having a bottom surface and side walls, comprising chuck means adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column, a head slidably mounted on said column, an abrading member carried by said head and adapted to engage the workpiece to polish the same, means for rotating said head around said column to position said abrading member in alignment with said chuck means, means for moving said head axially of the column to efiect engagement of the abrading member with the workpiece and to effect disengagement of the abrading memher with the workpiece after completion of the polishing operation, and means for biasing said abrading member toward the side wall of the workpiece to effect polishing of said side wall.

9. An automatic apparatus for polishing or otherwise abrading a workpiece, comprising a supporting structure, chuck means mounted on said supporting structure and adapted to support the workpiece, drive means for moving said chuck means in a given linear path of movement, a support column secured to the supporting structure, a frame slidably mounted on said column, an abrading member carried by said frame and adapted to engage the workpiece and abrade the same, means for pivotally connecting said abrading member and said frame to selectively vary the angle of attack of said abrading member on said workpiece, means for rotating said frame around said column to position said abrading member in alignment with said chuck means, means for moving said frame axially of the column to effect engagement of the abrading member with the workpiece and to effect disengagement .of the abrading member with the workpiece after completion of the abrading operation.

10. An automatic apparatus for polishing or otherwise abrading a workpiece, comprising a supporting structure, chuck means mounted on said supporting structure and adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column secured to the supporting structure, a frame slidably mounted on said column, an abrading member carried by said frame and adapted to engage the workpiece and abrade the same, means for effecting radial movement of at least a portion of the frame with respect to the column, and means connected to said portion of the frame for biasing said portion toward said column and thereby urging said abrading member into contact with the side wall of the workpiece.

11. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece, comprising chuck means adapted to support .the workpiece, drive means for moving said chuck means in a given path of movement, a support column, a head slidably mounted on said column, an abrading member carried by said head and adapted to engage the workpiece to polish the same, second drive means for rotating said head around the column to position said abrading member in alignment with said chuck means, reciprocating means for moving said head axially of the column to effect engagement of the abrading member with the workpiece and to effect disengagement of the abrading member with the workpiece after completion of the polishing operation, means actuated by the head as the same is moved toward said chuck means 'by said reciprocating means for starting said first drive means to move said chuck means in said path of movement, and means actuated by the head as the same moves ,away from said chuck means after completion of polishing for stopping said first drive means to stop movement of saidrchuck means.

12. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece having a bottom surface and side walls, comprising chuck means adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support member, a head slidably mounted on said member, an abrading member carried by said head and adapted to engage the workpiece to polish the same, second drive means for rotating said head around the support member to position said abrading member in alignment with said chuck means, locking means for locking said head against rotation when said head is in alignment with said chuck means, reciprocating means for moving said head axially of the member to effect engagement of the abrading member with the workpiece and to effect disengagement of the abrading member with the workpiece after completion of the polishing operation, means responsive to locking of said head by said locking means for actuating said reciprocating means to move said head toward said chuck means, means actuated by the head as the same is moved toward said chuck means by said reciprocating means for starting said first drive means to move said chuck means, means responsive .to a predetermined amount of movement of said chuck means for actuating said reciprocating means to move said head away from the chuck means, means actuated by the head as the same moves away from said chuck means for stopping said first drive means to stop movement of said chuck means, and means actuated by the head as the same reaches substantially the outermost position in the movement away from the chuck means for releasing said locking means and permitting free rotation of said head.

13. An automatic apparatus for polishing or-otherwise abrading and finishing a workpiece, comprising chuck means adapted to support the workpiece, drive means for moving said chuck means in a given path of movement in a horizontal plane, a vertical support column, a head slidably mounted on said column, an abrading member carried by said head and adapted to engage the workpiece to polish the same, second drive means for rotating said head around the column to position said abrading member in alignment with said chuck means, locking means for locking said head against rotation when said head is in alignment with said chuck means, reciprocating means for moving said head axially of the column to effect engagement of the abrading member with the workpiece and to effect disengagement of the abrading member with the workpiece after completion of the polishing operating, means responsive to locking of said head by said locking means for actuating said reciprocating means to lower the head with respect to the chuck means and effect engagement of the abrading member and the workpiece, means responsive to the completion of a given path of travel of said chuck means for actuating said reciprocating means and raising said head, means actuated by the head in the ,upper position thereof for releasing said locking means and permitting free rotation of said head, and means actuated by release of said locking lmealns to operate said second drive means and rotate said 14. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece, comprising a supporting structure, chuck means mounted on said supporting structure and adapted to support the workpiece, .drive means for moving said chuck means in a given path of movement, a support column secured to the supporting structure, a series of heads disposed in circularly spaced relation to said column and each of said heads having an abrading member, means for slidably mounting each of said heads on said column to permit vertical movement of the heads with respect to the column, second drive means for rotating said heads around the ,col-

umn to successively position each of the heads over said chuck means, reciprocating means for lowering the head positioned over the chuck means toward said chuck means to effect engagement of said abrading member with the workpiece and for raising the head away from the chuck means after termination of said polishing operation, locking means for locking the heads against rotation with a first of said heads being disposed in vertical alignment with said chuck means when said locking means is engaged, means responsive to engagement of said locking means for actuating said reciprocating means to lower said first head and efiect engagement of the abrading member and the workpiece, means responsive to the completion of a given path of travel of said chuck means for actuating said reciprocating means and raising said first head, means actuated by said first head on returning to the upper position thereof for releasing said locking means and permitting free rotation of said heads, means actuated by release of said locking means to operate said second drive means and rotate said heads to position the second of the heads over said chuck means, and means responsive to the positioning of said second head over said chuck means for actuating said locking means and thereby repeating the cycle of operations.

15. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece, comprising a supporting structure, chuck means mounted on said supporting structure and adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column secured to the supporting structure, a series of heads disposed in circularly spaced relation to said column and each of said heads having an abrading member, means for slidably mounting each of said heads on said column to permit vertical movement of the heads with respect to the column, second drive means for rotating said heads around the column to successively position each of the heads over said chuck means, reciprocating means for lowering the head positioned over the chuck means toward said chuck means to eifect engagement of said abrading member with the workpiece and for raising the head away from the chuck means after termination of said polishing operation, locking means for locking the heads against rotation with a first of said heads being disposed in vertical alignment with said chuck means when said locking means is engaged, means responsive to engagement of said locking means for actuating said reciprocating means to lower said first head and effect engagement of the abrading member and the workpiece, means actuated by the first head as the same is lowered for starting said first drive means and initiating movement of said chuck means, means responsive to the completion of a given path of travel of said chuck means for actuating said reciprocating means and raising said first head, means actuated by the first head as the same is raised for stopping said first drive means, means actuated by said first head on returning to the upper position thereof for releasing said locking means and permitting free rotation of said heads, means actuated by release of said locking means to operate said second drive means and rotate said heads to position the second of the heads over said chuck means, and means responsive to the positioning of said second head over said chuck means for actuating said locking means and thereby repeating the cycle of operation.

16. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece having a bottom surface and side walls, comprising chuck means adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column, a head slidably mounted on said column, an abrading member carried by said head and adapted to engage the workpiece to polish the same, second drive means for rotating said head around the column to position said abrading member in alignment with said chuck means, reciprocating means for moving said head axially of the column to effect engagement of the abrading member with the workpiece and to effect disengagement of the abrading memher with the workpiece after completion of the polishing operation, biasing means for biasing said abrading member toward the side wall of the workpiece to effect polishing of said side wall, means actuated by the head as the same is moved toward said chuck means by said reciprocating means for starting said first drive means to move said chuck means, and means actuated by said head as the same is moved toward said chuck means and responsive to actuation of said last named means for operating said biasing means.

17. An automatic apparatus for polishing or otherwise abrading and finishing a workpiece having a bottom surface and side walls, comprising chuck means adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column, a head slidably mounted on said column, an abrading member carried by said head and adapted to engage the workpiece to polish the same, second drive means for rotating said head around the column to position said abrading member in alignment with said chuck means, reciprocating means for moving said head axially of the column to effect engagement of the abrading member with the workpiece and to effect disengagement of the abrading member with the workpiece after completion of the polishing operation, biasing means for biasing said abrading member toward the side wall of the workpiece to effect polishing of said side wall, means actuated by the head as the same is moved toward said chuck means by said reciprocating means for starting said first drive means to move said chuck means, means actuated by said head as the same is moved toward said chuck means and responsive to actuation of said last named means for operating said biasing means, means responsive to the completion of a given path of travel of said chuck means for actuating said reciprocating means and raising said head, means actuated by a predetermined amount of movement of the head away from the chuck means to release engagement of said biasing means, and means actuated by said head and responsive to operation of said last named means for stopping said first drive means to stop movement of said chuck means.

18. An automatic apparatus for polishing or otherwise abrasing and finishing a workpiece, comprising a supporting structure, chuck means mounted on said supportstructure and adapted to support the workpiece, drive means for moving said chuck means in a given path of movement, a support column secured to the supporting structure, a series of heads disposed in circularly spaced relation to said column and each of said heads having an abrading member, means for slidably mounting each of said heads on said column to permit vertical movement of the heads with respect to the column, second drive means for rotating said heads around the column to successively position each of the heads over said chuck means, reciprocating means for lowering the head positioned over the chuck means toward said chuck means to effect engagement of said abrading member with the workpiece and for raising the head way from the chuck means after termination of said polishing operation, locking means for locking the heads against rotation with a first of said heads being disposed in vertical alignment with said chuck means when said locking means is engaged, biasing means for biasing said abrading member toward the side wall of the workpiece to effect polishing of said side wall, means responsive to engagement of said locking means for actuating said reciprocating means to lower said first head and effect engagement of the abrading member and the workpiece, means actuated by the first head as the same is lowered for starting said first drive means and initiating movement of said chuck means, means actuated by the first head as the same is lowered to actuate said biasing means, means responsive to the completion of a given path of travel of said chuck means for actuating said reciprocating means and raising said first head, means actuated by the first head as the same is raised for stopping said first drive means, means actuated by said first head as the same is raised for releasing engagement of said biasing means, means actuated by said first head on returning to the upper posit on thereof for releasing said locking means and permitting free rotation of said heads, means actuated by release of said locking means to operate said second drive means and rotate said heads to position the second of the heads over said chuck means, and means responsive to the POSI- tioning of said second head over said chuck means for actuating said locking means and thereby repeating the cycle of operations.

19. An automatic apparatus for abrading a workpiece, comprising chuck means to support the workpiece, drive means for moving said chuck means in a path of movement, a drum, a series of heads mounted in circularly spaced relation on said drum, an abrading member carried by each head and adapted to engage the workpiece to abrade a portion of the same, an indexing disc secured to the drum and having a series of notches spaced in conformity with the location of said heads, a drive pawl selectively engageable with said notches to rotate the drum a given increment and successively position each of the heads over the chuck means, means for lowering the head disposed over the chuck means to elfect engagement of the abrading member and the workpiece to thereby abrade the workpiece, and a locking member selectively engageable with said notches in said indexing disc to prevent rotation of said drum during the abrading operation.

20. In an automatic abrading apparatus for finishing a workpiece, chuck means mounted for universal movement in a given plane, a flexible endless drive member, a driven member connected to the chuck means and disposed in engagement with said endless drive member, cam means associated with said chuck means to provide a given path of movement for said chuck means as the driven member is driven by said endless drive member, said driven member and said cam means both having a polygonal peripheral configuration substantially similar to that of the workpiece to be finished, means for selectively preventing movement of said chuck means in a direction parallel to the longitudinal dimension of said endless drive member, means for selectively preventing movement of said chuck means in a direction normal to the longitudinal dimension of said endless drive member, resilient means connected to the endless drive member for permitting deflection of the flexible endless drive member as the driven member is pivoted about a corner thereof and the chuck means is restricted in movement normal to the longitudinal dimension of said endless member and for maintaining said endless drive member under a predetermined amount of tension during the deflection, and an abrading member disposed in alignment with said chuck means and adapted to engage the workpiece as the chuck means moves in the path of movement.

21. In an automatic abrading apparatus for finishing a workpiece, a polygonal-shaped chuck means including a central support column, means for mounting the central column for universal movement in a given plane, a flexible endless drive member, a driven member connected to said chuck means and disposed in engagement with said endless drive member, cam means associated with said chuck means to provide a given path of movement for said chuck means as the driven member is driven by said driving member, said driven member and said cam means both having a polygonal peripheral configuration substantially similar to that of the workpiece to be finished, means engageable with said support column for selectively preventing movement of said chuck means in a direction parallel to the longitudinal dimension of said endless drive member, means engageable with said central support column for selectively preventing movement of said chuck means in a direction normal to the longitudinal dimension of said endless drive member, and an abrading member disposed in alignment with said chuck means and adapted to engage the workpiece as the chuck means moves in said path of movement, said flexible drive member being deflected when the corners of the polygonal driven member engage said endless member and said first and second holding means are in engagement with said support column.

22. The structure of claim 3 and including a backing member associated with the endless drive member for preventing deflection of said endless member when said first and second holding means are out of engagement with said chuck means and said driven member is pivoted about a corner thereof to thereby elfect a lateral movement of the axis of the driven member and the workpiece with respect to the endless drive member, and means for moving said backing member out of association with said endless drive member when said first and second holding means are in engagement with said chuck means to thereby permit deflection of said endless drive member during rotary movement of said chuck means.

23. An automatic abrading apparatus for finishing a polygonal-shaped workpiece, comprising a supporting structure, chuck means mounted on said supporting structure for universal movement in a given plane, a flexible endless drive chain, a sprocket connected to said chuck means and disposed in engagement with said drive chain, a cam member associated with said chuck means and disposed in axial alignment with said sprocket, said sprocket and said cam means both having a polygonal configuration substantially similar to that of the workpiece to be finished, a cam follower connected to said supporting structure and disposed to ride on said cam member as the chuck means is driven by the sprocket and thereby provide said chuck means with a given path of movement, a backing member operably engageable with the endless drive chain for preventing deflection of the endless member, holding means engageable with the chuck means for selectively preventing linear movement of said chuck means, and means for moving said backing member out of operable engagement with said drive chain when said holding means is in engagement with said chuck means to thereby permit the drive chain to deflect during rotary movement of said chuck means.

24. An automatic apparatus for abrading a workpiece, comprising chuck means to support the workpiece, drive means for moving said chuck means in a path of movement, a turret, a series of abrading heads mounted in circularly spaced relation on said turret, an abrading member carried by each head and adapted to engage the workpiece to abrade a portion of the same, indexing means secured to the turret and having a series of indexing members spaced in conformity with the location of said heads, a drive member selectively engageable with said indexing members to rotate the turret a given increment and successively position each of the heads over the chuck means, and a locking member selectively engageable with said indexing means to prevent rotation of said turret during the abrading operation.

25. An automatic abrading apparatus for abrading a workpiece, comprising chuck means adapted to support the workpiece to be finished, said chuck means being mounted for movement in a plurality of directions within a plane and being mounted for rotary movement about an axis of rotation normal to said plane, holding means selectively and operably engageable with said chuck means for preventing movement of said chuck means in said directions within said plane, drive means separate from said holding means and synchronized with said holding means for rotating said chuck means about said axis when said holding means is in engagement with said chuck means and for moving said chuck means in said directions within said plane when said holding means is out of engagement with said chuck means, and an abrading member adapted to engage the workpiece and