US2187462A

US2187462A - Polishing machine

Info

Publication number: US2187462A
Application number: US108846A
Authority: US
Inventors: David E Mulholland
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-11-02
Filing date: 1936-11-02
Publication date: 1940-01-16
Anticipated expiration: 1957-01-16

Description

JUL 16 1940 D. E. MuLHoLLAND rousanm means Filed Nevjz, 1936 5 Sheets-Sheet 1 Y am' mw/am Jn. 16, 1940. n. E. MULHOLLAND PDLISHING MACHINE Filed Nov. 2. 1936 5 Sheets-Sheet 2 Jan. 16, 1940. lz.4 E. 4M-uLi-IOLLAIM'J POLISHING MACHINE 5 Sheets-Sheet 3 Filed Nov. 2. 1936 3 rwa/wbvb @Mingo/fand Jan. 1161,41940. D. E. MULHOLLAND POLISHING MACHINE Filed Nov. 2, 193e' 5 Sheets-Sheet 4 Jan. c16, 1940. D. E. MuLHoLLAND POLISHING MACHINE Filed Nov. 2. 1936 .aa'd E: @Zio/fand Patented Jan. l@ l entre"- sjrarss maaier Parser euries 44 Claims.

My invention relates to machines for polishm ing metal surfaces.. more particularly the surfaces of sheets of stainless steel and the like, for removing the open surface andi other defects usually present in metal sheets to produce what is customarily called a fundamental surface coni dition.

One of the principal objects of the invention is to provide extremely sensitive means for accurately controlling the pressure between the polishing roll or wheel and the-metal sheet.

Another object ofthe invention is to provide means for producing the desired pressure between the work and the polishing roll which will readily accommodate itself to variations in' thickness of a metal sheet but yet will resist. suelo.J

sudden. or abrupt movements 'as' would produce sudden changes in pressure on the sheetfthereby avoiding any change in the character of cut being made by the polishing roll which would result in marring the finish of the surface.

Another object of the invention is to control the rate of travel of the work past the polishing roll by the pressure producing means.

A further object of the invention is to provide improved means for supplying a coolantA to the metal sheet, so that the heat generated therein Y by the polishing roll will be rapidly dissipated and thus enable a greater amount of stools to be removed per pass than has heretofore been possible due to warping anti burning: of the sheet caused by the failure of the generated heat of abrasion to escape.

A primary feature of the invention consists in providingl the polishing machine with a pivoted' carriage upon which is mounted o. rotatable work supporting roll, the carriage being movm vabvle about its pivot to cause the work support ing? roll to move toward the polishing roll of the machine. l

Another feature of the invention consists in4 providing' the pivoted carriage with means for counterbslancing: the work supporting roll., so that the carriage itself will be in a state of equilibrium. i l

Another feature of the invention'consists in providing the machine with uuid pressure means for inducing pivotal movement of the carriage to move the work supportingn roll toward the polishing roll, the fluid pressure means," through the worlz supporting roll, serving to maintain the work in yielding engagement with the polm ishing roll,

A further feature of .the invention consists in providing an adjustable `stop limitins movement vworlr supporting roll away. from the ofthe work supporting roll towarthe polishing roll .so as to` prevent the rolls from contacting each other. v

Still another feature ci the invention consists in providing mechanism for rotating the work o supporting roll at a lpredetermined speed, the

mechanism including means preventing rotation of the supporting roll at a speed substantially in excess of the predetermined speed whereby the supporting roll will control the rate of movement lo of the work past the polishing roll. f

A still further feature of the invention consists in providing the carriage adjacent the work supporting roll with slrids for supporting the work, which are preferably vertically and angu- 15 larly adjustable with respect to the carriage.

A still further feature of the invention consists in providing means for supplying a coolant. under pressure to a portion of the work immediately adjacent the portion thereof in contact .2li with the polishing roll, the means discharging the coolant onto the work toward the polishing roll at-an oblique angle to the direction of travel of the work. l

Other and more speciilc features of the inven- 25 tion, residing in advantageous forms, combina.- tions and relations of parts. will hereinafter l appear and he pointed out in the claims.

In the drawings:

Figure l is a side elevation of machine. A

Figure 2 is a plan view of the machine. l

Figure 3 is a vertical sectional view taken on line @-3 of Fleurs 2. A h

Figure 4 is a vertical sectional view taken on 35 `line l-ii of l.

Figure 5 is a verticalsectional View line {iw-il of Maure l.

Figure o is a plan view of the coolantsupplying means.

Figure 'l is a side elevational view off one of the coolant supplying .means and the mechanism for adjusting it vertically.

Figure u is a detail view of the combined means for rendering inoperative the iluid pressure means 4 which rotates the carriage in onedirectiori for moving the work supportingn roll toward the pol-l the 4polishing# 3@ taken on I isiiing roll and for simultaneously rocking the x carriage in the opposite direction to move they polishing roll.

Figure 9 is an enlarged detail sectional view taken on a line corresponding to line 9 9 of Figure 1, illustrating the means for vertically 55 ad angularly adjusting the work supporting s ds.

Figure 10 is a detail side elevational view illustrating the mechanism for operating the means for actuating the movable stop which limits movement of the work supporting roll toward the polishing roll.`

I Figure 11 is an enlarged detail sectional view on line` II-II of Figure 3. i

Figure 12 isa detail sectional 'view taken on line I2--I2 of Figure 11. Y

Referring more particularly to the drawings, I the polishing machine comprises generally a work feeding table or section Ill, a work delivery table or section I I and a polishing unit or section I2 which is interposed between the feeding and delivery tables.

The polishing unit has a main frame I3 which is preferably formed as a unitary casting and includes side walls I4 connected by a base I5 which forms the bottom wall of .a coolant collecting chamber I6. The bottom wall I5 is spaced below ilanges or the like I1 projecting outwardly from the lower portions of the side walls I4 and resting upor the floor or other suitable support provided for the polishing unit. The side walls I4 are provided with upwardly projecting portions I9 aiording supports for bearings 20 ot the polishing roll 2l. 'I'he bearings, as well as their journals, are oaf exceedingly sturdy construction so as to provide in conjunction with the frame Il a very rigidV support for the polishing roll preventing it from vibrating or chattering.

The polishing roll is .preferably of the charace ter illustrated `and described in my Patent No. 2,106,186, andit may comprise abrasive grain of very small size, such as No. 240 or other sizes depending upon the character` of nish desired, bonded in a suitable organic material and made in the form of a sleeve to iit over a drum 22 mounted on an -axle 23. The axle projects beyond one ofits bearings 20 and is .provided witha pulley 24 having a plurality of peripheral yshaped grooves for cooperating with a drive belt 25 formed with a plurality of V-shaped portions on its inner surface-the belt being driven by -an electric motor 26 or other suitable means.

Pivotally mounted on the` frame I3 of the 'polishing unit adjacent one end thereof is a rigid carriage or the like ,21 having side members 2,8 which may advantageously be formed of cast metal.v Intermediate their ends, the side members are respectively formed with outwardly projecting hollow trunnions 29 which are* mounted in bearings 30 on the main frame Iiy and thus aord apivotal support for the carriage.

Mounted on the carriage so as to be positioned beneath the polishing rollJ2I is, the rotatable work supporting roll Il consisting of a drum 32 having an outer rubber covering 3l' and a shaft 34,'each end of which is provided with/a pair of spaced

bearing collars

36 and 36 which are journaled'lin the side members 26 of the carriage. Extending longitudinally of the carriage beneath the side members thereof for imparting rotation to the work supporting roll are shafts 31, each of which is provided 'at one end with a worm 38 and at its opposite end with a worm 'wheel 39. The worms 38 are disposed within housings 46 formed in the side members 28 of the carriage and they cooperate with worm wheeis 4 Iewhich are mounted -on shaft 34 between the bearing collars i6 and 36. Worm wheels 39 on shafts 31 are disposed A Within housings 42 in the side members 26 and they cooperate with worms 4l formed onta shaft 44 which is coincident with the pivotal axis of `the carriage and is journaled within the hollow pivotal axis of the carriage, it will be readily perceived that the work supporting or back-up roll 10 may be r tated in all pbsitionsof adjustment the carriageK may assume and that the mechanism for rotating it oers noresistance whetever to pivotal movement of the carriage. Moreover, as the roll is rotated through the intermedlacy of 15 Worm gears, it cannot be over-driven by the work, due to its, engagement with the more rapidly rotating polishing wheel, and 'accordingly the supporting roll serves to control the passage of the work past the polishing roll.

As the tendency of the polishing roll is to advance the travel of thesheet and the work supporting Aroll acts as a brake controlling the work travel, itis desirable to prevent any back-lash in the driving mechanism of the supporting roll 25 because, if there is lost motion in the mecha-A nism, the sheet, when it first enters between the rolls, will momentarily pause in its travel and its surface will be marked. To prevent this, shaft 44 is made in two sections which are adapted 30 to be rigidly connected by a coupling having flanges 44' for receiving securing bolts. The openings in one of the flanges are in` the form of arcuate slots so that before the bolts are tightened to rigidly connect the anges, the sections 35 of shaft 44 may be rotated in opposite directions until all lost motion in the train of parts is taken up.

To maintain the carriage in a condition of I equilibrium', it is provided -with an adjustable 4I) counterweight 48. While any suitable means kmay be employed for adjusting the counterweight ^to effect perfect balance of the carriage, this may be advantageously accomplished by mounting the counterweight on a rotatable screw/threaded shaft 49 winch is supported atl its opposite ends by brackets 66 projecting downwardly from the carriage. At one end, shaft 49 is provided with a bevel gear 5I which meshes with a similar gear 82 formed on .one end of a shaft 53 which is also 50 Supporting roll constitutes, vin effect, a floating e0 member which may be ,delicately controlled for producing the precise pressure required between the polishing roll and the work to obtain optimum results. f

To induce pivotal movement of the carriage causing the work supporting roll to move toward the polishing roll and to yieldingly maintain the work in engagement with the latter .under the desired pressure, two fluid containing chambers 66 are provided. l These chambers are respective- 70' ly positioned below Vthe bearingsof the work supporting roll and elch consists of'a cup-'shaped base portion 56 .and a tubular guide portion 51 within which is disposed a rubber diaphragm 66 9,187,462 tween the base and guidepomions. Resting upon the diaphragme 58 are cylindrical bosses or the like t@ which are secured to and depend from the side members of the carriage adjacent the housings M for the worm gears -I oi the work supporting roll.

'Ihechambers 55 are connected to a fluid pressure reservoir (air being the iluid preferably used) having a capacity many times that of bothchambers by means of conduits 6b which branch from a common conduit ti provided with amanually controlled valve 62. Byemploying iiuid pressure for maintaining e work in engagement with the polishingroil, i will be appreciated that the pressure exerted by the supporting roll may be accurately controlled. Moreover, as the work supporting roll is lyieldingly maintained in engagement with the work bythe fluid pressure, it will readily accommodate itself to changes of thickness in the work and it will exert a constant and uniform pressure yin all positions it may assume dueto 'variations in thickness oi'v .the

.Furthermore while the carriage is mounted so as to be extremely sensitive to the changes in thickness of the work, it has sufdcient mass so that it will resist such sudden or abrupt movements as would produce sudden changes in the pressure exerted by the supporting roll, whichwould result in changing the character. ofl cut being made by the polishing roll` and thus mar the finish of the surface. I

As it is desirable to set the polishing and work supporting rolls in motion before the work is led to the machine, means is employed for preventing the rolls from coming in contact with each other.v This means may comprise horizontally adjustable stop members 83 which are slidably mounted upon T-headed projections 64 extending inwardly from the side walls Il of the frame adjacent the portion of the carriage upon which the work supporting roll is mounted. The inner end s of the members 83 are inclined upwardly and they are adapted to cooperate with ledges or shoulders 05 which project outwardly from the side members' of the carriage and have inclined upper faces disposed in planes parallel with the inclined forward ends of members 83. Thus )it will be seen that movement of the carriage in a direction causing the work supporting roll to move toward the polishing roll will be arrested by the shoulders 65 of the carriage engaging the stop members 63 and that, by shifting the latter horizontally, the gap between the polishingv and supporting rolls may be easily controlled.A

It has been found preferable to set the stop members so that the gap between the two rolls will be approximately .010 inch less than the thicknesslof the sheet to be polished. i As the sheet enters between the rolls, the supporting roll will, therefore, move downwardly .010 inch and thus be free to act -as a iloating support. The stops may be adjusted by any suitable means, such, for example, by a rack and pinion mechanism which includes. a shaft 66 on which are mounted two pinions B1 for cooperating with teeth 88 formed on the upper surfaces of the stops. Shaft 66 is supported by bracket 69 and'lll which may be conveniently formed integral with the mainframe I3 of the machine and at one end it is provided with a gear wheel 1| cooperating with a larger gear wheel 12 mounted on a stub shaft "i3, which is also preferably journaled :in the bracket lil. Shaft 'i3 is .provided 'with a hand wheel ld whereby it may be easily rotated to effect rotation of shait 56 and it is also provided with a calibrated dial "l5 for indicating,

with reference to a pointer 'lf3 also secured to brackets lil, 'the space between the polishing and work supporting rolls.

As it is sometimes desirable to move'the work supporting roll away from the polishingamL suitable mechanism is provided for rendering the 'duid pressure means inoperative and for simultaneously vpivoting the carriage in a ydirection for causing downward movement of the work snpporting roll. l'his mechanism may advantageously consist oi an electric thrustor li hailing a plunger 'itl movably connectedto the outer end of a lever 79 which is pivotally mounted intermediate its ends on a suitably located bracket L50.

The inner end of lever 'i8 projects beneath the i outer end of ne carriage and itis adapted to engage any suitable portion thereof, such as one of the brackets 50, being guided in its movement between spaced lugs B2 formed integral with `the latter, so that. when the lever is rotated ina clockwise direction by downward movement'o'f the plunger 18 of the thrustor, the outer' end of the carriage will swing up and thus result in imoving the iwork supporting roll downwardly away from the polishing roll.

For cutting olf the supply of fluid pressure to the chambers 55 and for also relieving whatever pressure may be in the chambers at the time the thrustor is actuated to move the work supporting roll away from the polishing roll, a valve device 83 isdisposed in the main conduit fl. This device has a slide valve 84 which is mow/'ably connected to thel lever 19 so that, when the plunger of the thrustor is operated, the slide valve will move downwardly to shut oil the supply of uid and vent the chambers 55 to 'the atmosphere through a port 85 formed in the body of the valve. When the thrustor is in its normal inoperativeposition however, the slide valve is disposed inv a position enabling the free flow of iluid tothe chambers, provided, of course, the manually operable valve 62 is open. 'n

For bridging the spaces between the work supporting roll and the feeding and deliverytables, a skid 86 is mounted on the carriage closely adjacent the feeding side of the roll and a similar skid 81 is mounted on the carriage closely adjacent the delivery side of the roll. Each skid comprises a plurality of arms 88 suitably mounted in spaced relation on a supporting bar 39 which is provided adjacent each end with a pair of downwardlyextending spaced lugs Si! for receivingd '94, it will be perceived that the skids may be easily adjusted vertically and, by untightening the bolts 93, they may be adjusted angularly. Thus simple and eicient means is provided whereby the skids may be quickly adjusted so as to properly guide the work from the feeding table to the polishing roll and from the polishing roll to the delivery table.

The'

Mounted upon the main frame of the polishing unit on opposite sides of the polishing roll are chambers 91 for supplying coolant to portions of the work immediately adjacent the portion thereof in contact with the polishing roll. Each of the coolant supplying chambers, which may be advantageously formed of cast metal, progressively decreases in height toward Aits discharge end, so that the latter may be disposed near the point of contact between the work and the polishing roll and thus cause the coolant to diss charge directly onto portions of the work immediately adjacent. the 'portion in contact with thepolishing roll.l In the rear of each chamber 01 is formed a compartment 98 having a removable back plate 99 provided with means |00 through which coolant is supplied to the compartment. Communicating with the compartment 08 and extending forwardly therefrom are a plurality of ducts the discharge ends of ywhich are disposed as indicated at |02 so as to cause the coolant to issue therefrom at an oblique angle tothe direction of travel of the work. By causing the coolant to discharge onto the work in this manner under apressure preferably in excess of 250 pounds per square inch, the coolant will ilow transversely of the work at a velocity which will effect such emclent results' that the polishing wheel may remove a greater amount sidered possible.

nach of tneeooisnt Supplying chambers is' be conveniently jurnaled in brackets |00 rigid with the side walls of the frame I4 and at one end it extends through the adjacent side wall of the'fram'e where it is provided with a hand wheel |00. The polishing wheel is preferably enclosed by a sheet metal hood ||0 within which is mounted means for. freeing the periphery of the polishi g roll of particles of grit and other waste material which may adhere thereto. This means serves to forcibly project a fluid medium lat an exc l ly high pressure against the entire surface ,of the roll at least once in each revolution from a series fof nozzles mounted in a header ||2 which is connected to suitable means, not shown, for supplying iiuid under pressure.

- The discharge ends of the nozzles are disposed closely adjacent the periphery of the pol- .hhing roll, so that the fluid issuing therefrom lwill. upon each revolution ofthe roll,. readily dislodge Particles of grit and other matter adhering to its surface before the adhering matter i becomes impacted by repeated contacts with the work and gathers additional matter which would result in an adhering aggregate being built up on the surface of the roll. j; In addition' to the fluid pressure means for vipaning the surface of the polishing roll, a plu- 'ility. of deiiecting bellies ||3 are mounted within hood ill which serve to deflect and conduct .olthalidesoftherollthecoolantandcieanof stock per pass than has heretofore been con- A.

of the chamber.. The horizontal shaft |04 may ing fluid which discharges. tangentially from the roll and4 is ladened with abrasive wastes and thereby prevent this adulterated fluid, by being deflected from the hood, from entering the stream of ltered coolant emerging fromthe nozzles on the entry side of theroll. Each of the deflected bames ||3 is formed with a main body portion of arcuate shape, one end of which is attached to the inside of the hood and the opposite or free end of which is provided with a. strip of rubber III for engaging the surface of the roll.

While the work feeding table may be of any suitable construction, it is preferably provided withv a plurality of rollers ||5 which are driven through a train of gears H6. The axes of the rollers Il! are preferably 4inclined with respect to the axes of the polishing and work supporting rolls so asto maintain the work against the guide bar with which the table is provided and thus insure' the work being fed in the proper position to the polishing roll. e

The delivery. table is also provided with a plurality of rollers ||0 but these rollers need not 1 be positively driven. Interposed between the for-'- ward end of the deliveryA table and the rear end of the skid 01 are a plurality of rollers ||9 for conducting the work from the skid to the delivery table. These rollers are mounted in sup--l whereby theyy may be vertically adjusted so that they may, at all times, be disposed at substantially the same elevation as the skids 06 and 81 which are adjustable to take care of the work level as wear occurs on the grinding drum and the work supporting roll. The means for vertically adjusting theA elevation of the rear end of the feeding table and the front end of the delivery table may, if desired, consist of floor engaging pads or the like |22- having screw threaded portions |23 which extend upwardly into the vertical supports |24 of the tables and aresprovided with nuts |25 engaging the lower ends of the vertical supports. The feeding table is of such height at its front end that it will be several inches above the `highest point to which it is ever necessary to elevate the rear end and the rear end of the delivery table is likewise several inches higher than the front end thereof so that the coolant, as git spreads upon the work, will always tend to flow toward the center of the vmachine where it may be collected in the cham- From the foregoing, it will be perceived that? I have devised a rugged polishing machine having extremely sensitive means which may be ac curately controlled to maintain the work against the polishingl roll under the precise pressure desired. Furthermore, by reason of the means employed for supplying coolant to portions of gree is obtained.

The operation of applicants device is as fol lows: The sheet to be polished is placed upon thedriven-rolls illan'dduetotheangulari'gl aisance tated at high speed inthe direction of the arrows,

shown on Figures 1 and 3 tends to force the sheetA at a. high rate of 'speed toward the rolls lib.. This action is prevented owing to the fact 'that the work supporting roll is positively driven at a definite rate of speed and therefore limits the speed of passage of the plate. The supporting roll, owing to its pivotal support andto the diaphragm, is capable of une adjustment m that i lthe pressure of the plate against the poiis'hing roll may be regulated so as to limit the amountv of material removed from the surface of the plate. The adjustment of the skid table permits the skid table to be moved to compensate for the diil'erence :ln/diameter oi the 'polishing roll due to wear of 'its abrasive surface'.v The stop mechanism illustrated in detail in Figures 10, 11 and 12 provides for anqexceedingly accurate gage of the pressure which will be applied by the work supporting roll and at the same time prevents the work supporting roll from contacting with the polishing or abrasive the passage of one plate and the nex Various modications and changes in details of construction of the speciiic embodiment of the invention described and illustrated/herein may, of course, be made without departing from the spirit of the invention as denedrby the appended claims. v l l What I claim is: f

1. A machine for polishing metal sheets and the like, including a rotatable polishing roll, means for driving the polishing roll, a work supporting roll disposed beneath the polishing roll and movable with respect thereto in a substantially vertical direction, and mechanism -ior rotating the work supporting roll at a predetermined speed, said mechanism including means preventing the rotation of the supporting roll at a speed submantlally in excess of said predetermined speed whereby said supporting roll controls the movement of the work past the polishing roll.

2. A machine for polishing sheets and the like, including a polishing roll, means :for rotating the polishing rolLIo/vertically adjustable work supporting roll beneath the polishing roll, iluid pressure means for moving the work supporting roll upwardly to force the work into engagement ,with the polishing roll, andfmechanism for rotating said work supporting roll at a speed less than the speed of the polishing r ll, said mechanism including means for ma taining `the speed of rotation of the supporting roll less 'than the speed of rotation of the polishing roll.

3. A machine forpolishing metal sheets and the like, including a rotatable polishing roll having a substantially unyielding surface, means for driving the polishing roll, a work supporting roll.

having a yielding surface disposed neath the polishing roll and movable with respect thereto in a substantially vertical direction, and mechanism for rotating the work supporting roll at -a predetermined speed which is less than the speed of the polishing roll, said mechanism including means preventing rotation oi the suprollv between porting roll at a speed substantially in excess of, said predetermined speed whereby said supporting roll controls the movement of the work past the polishing roll.

4. Aimachine for polishing metal sheets and the like, including a polishing roll, a vertically movable work supporting roll disposed beneath the polishing roll, fluid pressure means providing a yielding support for the work supporting roll and for moving it toward the polishing roll, and mechanism for rotating said supporting roll in- I cluding meansnmovable with 'the latter whereby said mechanism is operative to drive said supporting roll in all positions it may assume.

5. ,A machine gior polishing metal sheets ,and the like, including a polishing roll, a work supporting roll, means for -rotating the work supporting roll, .iluid pressure means for moving the Work supporting roll toward the polishing roll, and an adjustable stop for limiting the extent of movement of-said work supporting lroll toward -the polishing roll.

6. A machine for polishing metal sheets and the like, including a polishing roll, a work supporting roll movable toward the polishing roll, nuid pressure means for yieldingly-maintaining the supporting roll in contact with the work, and adjustable means limiting movement of the supporting roll toward the polishing roll whereby the supportingl roll may be initially set so as to provide a predetermined gap between it and the polishing roll.

7. A machine for polishing metal sheets and the like, including a polishing roll, a pivotally mounted carriage, a rotatable Work supporting roll mounted on the carriage and disposed beneath the polishing roll, the axis of the supporting roll and the pivotal axis of the carriage being laterally spaced and being disposed in substantially the same horizontal plane, and means cooperable with the carriage adjacent the supporting ln'oll to cause said carriage to pivot and thereby move'the supporting roll relatively to the polishing roll. i

8.,"A machine :for polishing sheets and the like, including a polishing roll, a pivoted carriage,`a rotatable work supporting roll disposed beneath the polishing roll and mounted on said carriage, said work supporting rollfbeing spaced horizontally from the pivotal axis o1' the carriage, and yieldable means cooperable with the carriage at a point spaced from the pivotal anis thereof for causing the supporting roll to maintain the work in contact with 'the polishing roll.

9. A machine iorfpolishing metal sheets and the like, including a polishing roll, a pivoted carriage, a Ywork supporting roll disposed beneath the polishing roll and mounted on said carriage, :duid pressure means :lor causing said carriage to move the work supporting roll toward the polishing roll, said huid pressure means serving to maintain the work with the' polishing roll.

10. A machine for polishing metal sheets and the like, including a polishing roll, a pivoted carriage, a work supporting roll disposed beheath the polishing roll and :mounted on said carriage on one side of the pivotal axis thereof, means inducing pivotal movement of the carriage for causing the work supporting roll to move toward the polishing roll, and means on said carriage for counterbalancing the work supporting ro l.

l1. A machine for polishing metal sheets and in yielding engagement the like, including a polishing roll, a pivotally mounted carriage, a work supporting roll dis-l posed beneath the polishing roll and mounted on said carriage, means on said carriage counterbalancing said work supporting roll, means for pivoting said carriage to move the work supporti-ng roll ,toward the polishing roll, and adjustable means for limiting movement of said carriage in a direction causing. the work supporting roll to move toward the polishing roll, said adjustable means serving to prevent the supporting roll from contacting the polishing roll.

12. A machine for polishing metal sheets and the like, including ir-polishing roll, a carriage pivlotally mountedi intermediate its ends, a work supporting roll mounted on the carriage on one side of its pivotal axis, means on the carriage on the other side of its pivotal axis for counterbalancing the work supporting roll, and iluid pressure means for inducing pivotal movement of the carriage to move the work supporting roll toward the polishing roll.\ n V 13. A machine for polishing metal sheets and the like, including a polishing roll, a carriage pivotally mounted intermediate its ends, al work supporting roll mounted onvthe carriage on one side of its pivotal axis and movable toward the polishing roll upon pivotal movement of the carriage in one direction, means mounted on the carriage for counterbalancing the work supporting roll, and yieldable means cooperable with the carriage forresisting movement thereof in a direction causing the supporting roll to move away from the polishing roll.

'14. A machine for polishing metal sheets and the like, including a polishing roll, a carriage pivotally mounted intermediate its ends, a work supporting roll mounted on the carriage on one side of its pivotal axis. and adjustable means mounted on the carriage on the other side of its pivotal axis for counterbalancing the work supporting means, and means for inducing pivotal 'movement of the carriage to cause the work supporting roll to, move toward the polishing roll.

l5. AA machine for polishing metal sheets and the like, including 'a polishing roll, a pivoted carriage, a work supporting roll mounted on the carriage in spaced relation to the pivotal axis thereof, and mechanism for inducing pivotal movement of the carriage to move the work supporting roll toward the polishing roll, said mech-'- anism including a flexible diaphragm, a member mounted on the Vcarrlage'engageable with the diaphragm, and iiuid pressure means for actuating said diaphragm.

. 16. A machine for polishing metal sheets and the like, including a polishing roll, a pivoted carriage, a rotatable work supporting roll mounted on the carriage in spaced relation to the pivotal axis thereof, means for inducing pivotal mo'vement of the carriage to move the work supporting roll toward the polishing roll, and mechanism for rotating the work supporting roll including a rotatable shaft having its axis coincident with the pivotal axis of the carriage.

17. A machine for polishing metal sheets and the like including a polishing roll, a pivoted carriage, a rotatable work supporting roll mounted on the carriage in spaced relation to the pi'votal axis thereof, means for inducing pivotal movement of the carriage to move the work supporting roll toward the polishing roll, and mechanism for rotating the work supporting roll including a main drive shaft having its-axis coincident with the pivotal axis of the carriage and means carried by the carriage operatively ctnaumen opposite direction.

necting said drive shaft and for imparting rotation to the latter. s

18. A machine for polishing metal sheets and the like, including a polishing roll, a pivoted carriage, a work supporting roll mounted on the carriage in spaced relation to the pivotal axis thereof, skids mounted on the carriage adjacent the supporting roll for supporting the work, means for inducing-pivotal movement 'of the carriage fr moving the supportingroll and skids toward the polishing roll.

19. A machine for polishing metal sheets and the like, including a polishing roll, a pivoted carriage, a-.work supporting roll mounted on the carriage in spaced relation to the pivotal axis thereof, skids carried by said carriage and disposed on opposite sides of the supporting roll for supporting the work, and meansvfor inducing pivotal` movement of the carriageto move the supporting roll and skids toward the polishing roll. n I K 2&5. A machine for polishing metal sheets and the like, including a polishing roll, a pivoted carriage, a work supporting roll mounted on the carriage in spaced relation to the pivotal axis thereof, skids mounted on the, carriage adjacent thesupporting roll for supporting the work, means for inducing pivotal movement ofthe carwork supporting roll riage i'or moving the supporting roll and skids toward the polishing roll, and means for vertical- 1y adjusting said skids with reference to said carriage.

21. A machine for polishing metal sheets and the like, including a vpolishing roll, a pivoted carriage, a work supporting roll, mounted on the carriage in spaced relation to the pivotal axis thereof,'.skids can'ied by said carriage and disposed on opposite sides of the supporting roll for supporting the work, means for inducing pivotal movement of the to move the supporting roll and skids toward the polishing roll, and means for vertically and angularly adjusting said skids with reference to the carriage.

22. A machine for polishing metal sheets and the like, vincluding a polishing roll, a pivoted carriage, a work supporting roll mounted on the carriage, iluid pressure means'for inducing pivotal movement of the carriage to move the supporting roll toward the polishing roll, and means for pivoting the carriage to cause the supporting roll to move away from the polishing roll.

23. A machinei'or polishing metal sheets and the like, including a polishing roll, a pivoted car-v riage. a work supporting roll mounted on the carriage, fluid pressure means for inducing pivotal movement of the carriage to move lthe supportingv ing through the axis oi'. the polishing roll for supplylng a coolant under pressure to the portions of the work immediately adjacent theportion thereof in contact with the polishing roll,v one o! said coolant supplying means causing the' coolant discharging therefrom to iiow parallel to the axis i of said roll in one direction and the other of said gieans causing the coolant discharging from it to owparalleltotheaxisoftherolllmtintheh ter-balancing means on the work support on the other 'side of said pivot means to neutralize gravitational eiiect on the work-engaging means, a diaphragm, a boss attached to said work supvport resting on said diaphragmand vout of {rictional sliding contact with other parts, controlled pressure means for moving said diaphragm to urge the work through the work-engaging means toward said polishing wheel, and means to limit the movement of the work-engaging means to prevent its contacting the polishing wheel.

36I In a machine or polishing metal surfaces, a rotatable polishing wheel, a work support,

. means for pivoting saidwork support intermediate its ends, means on said work support on one side of the pivot means to engage the work for backing up the latter and to control the feed thereof, counter-balancingmeans on the work support on the other side of said pivot means to neutralise gravitational effect-on the work-engaging means, a diaphragm, a boss attached to said work support resting on said diaa phragm and out o! frictional sliding contact with other parts, controlled pressure means :tor moving said diaphragm to urge the work through the work-engaging means of said work support toward said polishing wheel, and separate means at the counter-balancing end of the work support to rock the latter away from the work.

' 37, In a machine' for polishing metal surfaces.

va rotatable polishing wheel, a work support,

lmeans for pivoting said work support intermediate its ends, means on said work support on one side or the pivot means to engage the work for backing up the .latter and to control the feed thereof, counter-balancing means on the carriagev on the other side of said pivot means to neutralize gravitational eil'ect on the workengaging means, a diaphragm, a boss attached to said carriage resting on said diaphragm and out oi' trictional sliding contact with other parts, l

' andan air pressure chamber for operating said diaphragm,-`and means to adjust the counterbalancing means.

38. In a machine for polishing metal surfaces. a rotatable polishing wheel, a work support, means for pivoting said work support intermediate its ends, means on said work support on one side of the pivot means to engage the work :for backing up the latter'and to control the reed thereof, counter-balancing means on the work support on the other sideoi said pivot means to neutralise gravitational elect on the work-engaging means, a diaphragm. a boss -attached to said .work support resting on said diaphragm and out of frictional sliding contact with other parts, andan air pressure chamber for operating said diaphragm, and means to move the work-engaging means on said work support 'away from, the polishing wheel.

sa. 1n a machine for ponsmng menu surfaces.'

portion `attached ito said work 4,support'andanV vairgpressure chamber. ioroperating said disphragm, and means to move the work-engaging means in said work support away from'the polishing wheel and at the same timeautomatically relieve the diaphragm pressure thereon.

40. In a machine for polishing reotilineal metal surfaces, a rotatable polishing wheel having a peripheral work engaging surface oi a denite character which is maintained during the polishing operation, a rockable work-support arranged Vbeneath said wheel, meansior counter-balancing said work support and movable to a plurality of adjusted positions relative to said support, a controlled iluid pressure -device operable by uid at predetermined pressure values for transmitting a predetermined pressure value corresponding to the intensity ofl the applied huid, and means-responsivel with said pressure device and actuated thereby to rock said work support toward the polishing wheel and lift the work upwardiy into engagement therewith.

41., In a machine for polishing metal surfaces, a rotatable polishing wheel, a work support, means for pivoting said work support intermediate of its ends, means on said work support on one side of the pivotlmeans to engage the work for backing up the latter, a diaphragm, and controlled i'iuid pressure means for movingy said diaphragm to urge the work through the work engaging means of said work support toward said polishing wheel.

42.- In a machine for polishing metal surfaces, a rotatable polishing wheel, a work support, means for pivoting said work support intermediate of its ends, means on said work support on one side oi the pivot means to engage the work .for backing up the latter, a diaphragm, a boss atached to said work support resting on said dia-.- phragm and out of irictional contact with the other parts, and a iluid pressure chamber for operating vsaid diaphragm to urge the work through the work engaging means of said work support toward said polishing wheel.

43. In a machine flor polishing metal surfaces, a rotatable polishing wheel, a work support, means for pivoting said work support intermediate of its ends, a rotatable member on said worksupport on one side of the pivot means to engage the workfor backing up the latter, a diaphragm, a boss attached to said workv supportresting on said diaphragm and out of frictionaf'sliding contact with the other parts, and a contrwolled uid '1 pressure means for operating said diaphragm to urge the work through the work engaging means of said worksupport toward said polishing wheel.

`4i.'In a machine for polishing metal surfaces,

a rotatable polishing wheel, a work support. means for pivoting said work support intermediate of its ends, means on said work support on one side of the pivot means to engage thel work for backing upthe latter, a diaphragm, aA boss attached to said work Support resting on said diaphragnr and out of frictional sliding contact with the other parts, a iluid pressure chamber for operating said diaphragm to urge the work through the work' engagingmeans of said work support toward said polishing wheel, and means to move the work engaging means on said work support away from the polishing wheel and at the samel time automatically. relieve the diaphragm pressure' thereon.

Y DAVID E. MULHOLLAND.