US2165616A

US2165616A - Polishing machine

Info

Publication number: US2165616A
Application number: US151426A
Authority: US
Inventors: John P Cox
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1937-07-01
Filing date: 1937-07-01
Publication date: 1939-07-11
Anticipated expiration: 1956-07-11

Description

July 11, 1939. p cox 2,165,616

POLISHING MACHINE Filed July 1, 1937 2 Sheet S-Sheet 1" -53 I L5 HTTOENEKS:

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' July 11, 1939. J. P cox 2,165,616

POLISHING MACHINE Filed July 1, 1937' 2 Sheets-Sheet 2 lnllllml Patented July 11, 1939 POLISHING MACHINE John P. Cox, St. Louis, Mo., asslgnor to General Motors Corporation, Detroit, Mich" a corporation of Delaware Application July 1, 1937, Serial No. 151,426

My invention relates to polishing machines, particularly to machines for sandpaperirig the metal tops of automobile bodies. The invention has for its principal object a machine which will do sandpapering automatically, including the feeding of. the sandpaper across the work engaging member. The invention consists principally in a polishing shoe mounted above the work on a support that swings in a vertical plane and is capable of free tilting movement longitudinally and transversely of the work, together with automatic means for intermittently feeding sandpaper or the like across the work engaging member. The invention further consists in the polishing machine and in the parts and combinations and arrangements of parts hereinafter described and claimed.

In the accompanying drawings,

Fig. 1 is a front elevation of apolishing machine embodying my invention,

Fig. 2 is a side elevation,

Fig. 3 is a plan view looking in the directions of the arrows 3-3 in Fig. 1,

Fig. 4 is a sectional view on the line 4-4 in Fig. 3, v

Fig. 5 is a sectional view on the line 55 in Fig. 6 is a sectional view on the line 66 in Fig. 1,

Fig. 7 is a detailed view of the ratchet and pawl mecham'smfor feeding the sandpaper,

Fig. 8 is a bottom plan view of the work engaging shoe-with the cover therefor removed,

Fig. 9 is a plan view showing the mounting of the polishing machine and the drive meanstherefor; and

Fig. 10 is aside elevation.

The present operation of polishing or sandpapering the tops of metalautomobile bodies requires the services of four workmen, each of whom sandpapers one-fourth of the top surface as the body moves longitudinally along the assembly line.

My invention greatly expedites this polishing operation by mounting the abrasive material on.

hrough holes 8 in bosses 9 projecting from said carriage I. Collars Hi on said arms 6 engage the inner faces of the bosses 9 and nuts II on the threaded outer end portions 12 of said arm-s engage the outer faces of said bosses 9. Thus, the hanger arms 6 are movable in a vertical plane about the horizontal axis formed by the end portions I of the arms 6. The downward, movement of the hanger arms is limited by stop members 13 projecting from the carriage 4.

Said arms 6 converge toward their lower ends ll. Said ends H are bent into a position approaching the horizontal and to them is secured, as by welding, a hanger plate l5 having depending plates It in which is mounted a shaft I'l that is disposed longitudinally of the work and assembly line. Plvotally mounted on said shaft I1, preferably with a bearing sleeve l8 interposed therebetween, is a hanger block l9 through which extends a shaft 20 that is disposed at right angles to said shaft II, that is, transversely of the work. A bearing sleeve 21 is interposed between said block 19 and said shaft 20. The ends of said transverse shaft 20 extend into upstanding side walls 22 of the shoe or work engaging member l and are secured thereto by means of set screws 23 and nuts 24. The shoe proper I can thus pivot about said transverse shaft-.20 in a vertical plane extending longitudinally of the work and said hanger block l9 canpivot about said longitudinal shaft ll in a vertical plane transverse to the work, so that the shoe as a whole is freely tilt-' able, substantially universally, with respect to the work and can accommodate itself to curvature of the work, whether the work be curved longitudinally or transversely, or both, as in the case of the top of the automobile body 3, diagrammatically indicated in the drawings.

The'bottom'or work engaging portion of the shoe has marginal ribs 25which extend generally longitudinally of the work, but have concave inner faces 26. Extending from rib 25 to rib 25 and over the outer faces 21 thereof is a pad 28 of rubber or other-resilient material which is secured to the outer faces of the shoe as by screws Secured to the ends of the shoe I, as by screws 30, are end plates 3| which have upwardly projecting portions 32 at one end. Mounted on a roller 33 between the tops of said projecting portions is a roll of sandpaper 34 'or other abrasive material. Said sandpaper 34 passes under a steady roll 35 that is rotatably mounted between .the lower portions of the end plate projections, and over a large guide roll 36 rotatably mounted between the end plates 3|. The portion of the sandpaper 34 engaging the upper portion of said guide roll 38 is engaged by a Steady roll 81 rotat-' ably mounted. between the end plates ii and a steady roll 38 engages the lower portion of the sandpaper 34 .as it leaves said guide roll 38. The ends of said lower steady roll 38. project through slots 88 in the end plates 8| and springs 48 urge said lower steady roll toward the guide roll 38.

pends from one arm 41 of a feed lever (indicated generallyby- 48) pivotally mounted on one end of the feed roll 42. A spring 4s secured to the other arm 58 of said feed lever 48 and to one end plate 8| urges the lever 48 in a direction to let the pawl 48 slide over one or more ratchet wheel teeth iii to engage one tooth ready for the next feeding movement. An upwardly projecting contact arm 52 at the end of said feed lever. 48 remote from the pawl .48 has a contact screw 53 projecting therefrom for engagementwith a contact bar 54 projecting from the hanger plate I8,-said engagement causing swinging of the feed lever 48 to rotate the ratchet wheel 48. The operation of this feedmechanism will be fur ther described hereinafter.

Secured between the lower portions of the hanger arms Sis a brace 55 from which depends a leg 88 to the bent lower portion 81 of which is pivotally mounted a caster wheel 58 which is disposed slightly above the level of the bottom of the shoe l. Preferably said leg 51 has a telescoping sleeve portion 89 secured to the leg 58 by a set screw 88 so that the vertical position of the wheel or roller 88 may be-adjusted.

The drawings diagrammatically illustrate a suitable drive mechanism for the crane 4a on which the carriage 4 is mounted, including a motor 8 I drive belts 82, driven gears 88, chains 84, idler gears 85, a cross pin 88 secured to the two chains 84, and a connecting rod 81 having one end pivotally mounted on said cross pin 88 and the other end on apin 88 projecting from said crane. I

As the automobile body I or other work moves longitudinally along the assembly line (the mechanism therefor not being shown) it will pass under the hanger arms 8, which are in the position shown in Fig. 2 until the front end of the work engages the caster wheel 88, slightly raising the hanger arms and the shoe and bringing the shoe I into operative engagement with the top'2 of thework. Preferably the shoe and associated parts are so balanced that the shoe tilts slightly to present the working surface of the work. The shoe I will then move back andforth across the work as the work moves longitudinally, the two movements beingrso correlated asto give a thorough sandpapering of all portions of the top of the work. Ordinarily, the work will be sprayed with water during the sandpapering process. At one end of the travel of the shoe over the transversely curved work, the shoe will be tilted about the longitudinally extending axis so as to bring the contact screw 53 into engagement with the contact bar 84 and cause the feed lever to be swung to operate the ratchet wheel 48. By adjusting the position of the contact screw 88 and looking it in adjusted position bymeans-of a lock nut. 88, the'stroke of the feed lever 48 can be changed so as to increase or decrease the amount of rotation of the feed wheel 48 and hence the amount of sandpaper fed at each stroke. v

. Obviously, the above described machine is fully automatic in its operation. 'I'hework shoe is able to conform automatically to work that is curved longitudinally or transversely orboth and the resilient work pad permits the sandpaper to.

accommodateitself to any slight surface irregularities in the work The sandpaper is auto--' matically fed at intervalsacross the work pad so as to continuouslybring fresh areas of the sandpaper into engagement with the work.

The invention is applicable to either wet or dry polishing operations and to operations using other polishing material than sandpaper.

0bvious1y, numerous changes may be made without departing from the invention and I do not wish to be limited to the preciseconstruction shown. 1

What I claim is: d

1. Automatic polishing tudinally and transversely curving work moving mechanism for longilongitudinally, comprising a support pivotally I mounted for vertical-:swinging movement above.

the work, a shoe suspended from said support to engage the .work and freely tiltable longitudinally and transversely of thework, said shoe having marginal ribs extending lonsitudinallyof they work, a resilient pad extending from rib to rib and secured to the outer facesthereof, a sheet.

of polishing material covering said resilient pad, and means for reciprocating said shoe transversely of the work as it moves longitudinally.-

2. Automatic polishing mechanismfor longitudinally and transversely curving work moving longitudinally, comprising a support pivotally mounted for vertical swinging movement above the work, a shoe suspended from said support toengage the work and freely tiltable longitudinally and transversely of the work, said shoe having marginal ribs extending longitudinally of the work, a resilient pad extending from rib to rib and secured to the-outer faces thereof, a sheet of polishing material covering said resilient pad,- means for intermittently feeding said sheet of polishing material across said resilient pad and means for reciprocating said shoe transversely of the work as it moves longitudinally.

3. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a support pivotally mounted for vertical swinging movement above the work, a shoe suspended from said support to engage the work and freely tiltablelongitudinally and transversely of the work, said shoe having marginal ribs extending longitudinally of the work, a resilient padextending from rib to rib and secured to the outer faces thereof, a sheet of polishing material covering said resilient pad,

means actuated by the tilting of said work shoe .at one end of its movement over the work for intermittently feeding said sheet of polishing material across said resilient pad and-means for reciprocating said shoe transversely as it moves longitudinally.

4. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a carriage mounted on a track extending transversely of the work some distance thereabove, means for reciprocating said of the work carriage along said track, a pair of hanger arms ing plates depending from the ends of said hanger plate, a shaft mounted in said mounting plates, a hanger block pivotally mounted on said shaft, a shaft pivotally mounted in said hanger block at right angles to said first shaft, a work shoe having upstanding ribs spaced from the sides of said hanger block and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted over said ribs, a sheet of abrasive material extending across, said resilient pad and supporting and feed means for said abrasive material.

5. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a carriage mounted on a track extending transversely of the work some distance thereabove, means for reciprocating said carriage along said track, a pair of hanger arms pivotally secured to said carriage for vertical swinging movement, said arms converging downwardly, a hanger plate secured to the approximately horizontal lower end portions of said arms and disposed longitudinally of the work, mounting plates depending from the ends of said hanger plate, a shaft mounted in said mounting plates, a hanger block pivotally mounted on said shaft, a shaft pivotally mounted in said hanger block at right angles to said first shaft, a work shoe having upstanding ribs spaced from the sides of said hanger block and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted over said ribs, a sheet of abrasive material extending across said resilient pad, supporting and feed means for said abrasive material including a feed roll having a ratchet wheel secured thereto, a feed lever pivotally mounted on the end of said feed roll adjacent to said ratchet wheel, a feed pawl depending from one arm of said feed lever, a retracting spring for said feed lever, a contact arm projecting from said feed lever at the end remote from said pawl, a contact screw projecting upwardly from said contact arm and a contact bar projecting from said hanger plate in position to be engaged by said contact screw when the shoe is tilted at one end of its movement over the transversely curving work.

6. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a carriage mounted on a track extending transversely of the work some distance thereabove, means forreciprocating said carriage along said track, a pair of hanger arms pivotally secured to said carriage for vertical swinging movement, said arms converging downwardly, stops for limiting the downward movement of said arms, a hanger plate secured to the approximately horizontal lower end portions of said arms and disposed longitudinally of the work, mounting plates depending from the ends of said hanger plate, a shaft mounted in said mounting plates, a hanger block pivotally mounted on said shaft, a shaft pivotally mounted in said hanger block at right angles to said first shaft, a work shoe having upstanding ribs spaced from the sides of said hanger block and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted over said ribs, a'sheet of abrasive material extending across said resilient pad, and supporting and feedmeans for said abrasive material.

'7. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a carriage mounted on a track extending transversely of the work some,

distance thereabove, means for reciprocating said carriage along said track, a pair of hanger arms pivotally secured to said carriage for vertical swinging movement, said arms converging downwardly, a hanger plate-secured to the approximately horizontal lower end portions of said arms and disposed longitudinally of the work, mounting plates depending from the ends of said hanger plate, a shaft mounted in said mounting plates, a hanger block pivotally mounted on said shaft, a shaftpivotally mounted in said hanger block at right angles to said first shaft, a work shoe having upstanding ribs spaced from the sides of said hanger block and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted on said ribs, a sheet of abrasive material extending across said resilient pad, a depending leg having its upper end mounted between the lower end portions of said converging arms, a caster wheel mounted at the bottom of said legs to be engaged by the work in advance of said shoe, thereby raising the shoe into operative position, and feed means for said abrasive material actuated by the tilting of the shoe at one end of its movement over the transversely curving work.

8. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudnally, comprising a carriage mounted on a track extending transversely of the work some distance thereabove, means for reciprocating said carriage along said track, a pair of hanger arms pivotally secured to said carriage for vertical swinging movement, said arms converging downwardly, a hanger plate secured to the approximately horizontal 'lower end portions of said arms and disposed longitudinally of the work, mounting plates depending from the ends of said hanger plate, a shaft mounted in said mounting plates, a hanger block pivotally mounted on said shaft, a shaft pivotally mounted in said hanger block at right angles to said first shaft, a work shoe having upstanding ribs spaced from the sides of said hanger block-and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted on said ribs, a sheet of abrasive material extending across said resilient pad, a depending leg having its upper end mounted between the lower end portions of said converging arms, a caster wheel mounted at the bottom of said legs to be engaged by the work in advance of said shoe, thereby raising the shoe into operative position, means for adjusting the vertical position of said caster wheel, and feed means for said abrasive material actuated by the tilting of the shoe at one end of its movement over the transversely curving work.

9. Automatic polishing mechanism for longitudinally and transversely curving work moving longitudinally, comprising a carriage mounted on a track extending transversely of the work some distance thereabove, means for reciprocating said carriage along said track, a pair of hanger arms pivotally secured to said carriage for vertical swinging movement, said arms converging downwardly. a-hanger plate secured to the approximately horizontal lower end portions of'said arms and disposed longitudinally of the work, mounting plates depending-from the-ends of said hanger plate. a shaft mounted in said mounting plates and disposed longitudinally with respect to the work, a hanger block pivotally mounted on said shaft, a shaft pivotally mounted in said hanger block transversely to said first shaft and to the work, a work shoe having upstanding ribs spaced from the sides of said hanger block and secured to said transverse shaft, said shoe having depending ribs on its lower or work face extending substantially longitudinally of the work, a resilient pad mounted over said ribs, end plates secured to the ends of said shoe and having upstanding supports at one end, a roll of abrasive material rotatably mounted in said supports, said abrasive material being directed across said resilient pad, feed means for said abrasive material including a feed roll having a ratchet wheel secured thereto, a feed lever pivotally mounted on the end of said feed roll adiacent to said ratchet wheel. a feed pawl depending from one arm of said feed lever, a retracting spring for said feed lever. a contact arm projecting from said feed lever at the end remote'from said pawl, a'contact screw projecting upwardly from said contact arm and a contactbar projecting from said hanger plate in position to be engaged by said contact screw when the shoe is tilted at one end 'of its movement over the transversely curving work.

JOHN P. cox.