US1790041A - Power press - Google Patents

Description

Jan. 27, 1931. CROSSLEY 1,790,041

POWER PRESS Filed Nov. 16, 1928 2 Sheets-Sheet l 00 wk/ C'roSa/gy Jan. 27,-1931. c ss 1,796,041

POWER PRESS Filed Nov. 16, 1928 2 Sheets-Sheet 2 Patented Jan. 27, 1931 T UNITED sTA r-"Es eem a g DAVID oRossLEY, or TREN'r-omN -W JERSEY rowns PRESS,

itpplication filed November 16,1928. 'Sriilfioi'fii'fifi. t

object by disengagin the driving disksfr'om the. horizontal 'wheel as the plunger completes its ,upstroke, or by provid ng a; brake to bring the horizontal Wheel to rest as it approaches the upward limit of its travel. A serious objection to these arrangenjien't's is that they either allow the driving disk to remain in contact with the horizontal Wheel when the latter is held against movement by a brake, thus causing wear of the'parts'i'n the form of a flat spot? on the horizontal Wheel, or they do not properly absorb the'inertia of the horizontal Wheel. 'It is an object of my invention to provide means for automatically disengaging the driving disksfroin the horizontal Wheel as the plunger approaches the upward limit of its travel, and to combine with this arrangement a brake to bringfthe horizontal Wheel to rest immediately after neutral position. In other Words, my-iiive'ntion contemplates means for disengaging the .friction drive before the driven 'ineinber is braked, so that the Wearing of fiat spots on effectually prevented.

A further objectis to provide apress of the reciprocating plunger type adapted to compress inaterial in a two-part die with fluid pressure means for positioning the die parts automatically, under the control of'an operator, as the compressing plunge r head moves to and from the die. I accomplish'this ing meansto control fluid pressure for openapproaches the limit of its upstroke] Ithas heretofore been proposed-t0"accemplisl gthis tion proceeds.

'bodying my invention;

the drivingdisks have been placed in their the friction surface of the driven wheel is,

object byproviding'a valveaiid Valve operating the die torece'ive tliemateiial to be t'z'oifn- I pressed, for removingfluid'pressure as the plunger moves toward the'die'injits com- 'pressing stroke, and rorreversing the fluid pressure to close'o'r strip-thedie and eject the compressed material asthe phmgr move's away from the die :after completion of the compressing stroke. 7 r

' Another object is tepr'o'v'ide means to inalte possible ready and ac'ci'irate' aujustmeiite the 60 capacity attire-die forreceivingmaterial t i V be compressed, thereby varying, at the Will of an operator, thethickne ss er the" resulting product. Various means have been proposed,

to regulate'th'e diecapa'c 'y, h far'as'l 55 i "ssible 1)r'ior'to-'inyam aware it has not beenp present invention to make this a'djustn'ient' instantly-and accurately {While the {press-is in operation; 7 7 e i r Other-and-fur'ther o'b eet's and advantages 3 of the invention 'ivill appear -as'theldescrip- In the accompanying" drawings which form parto'f this application for Letters Patent, which illustrate the embodiment of my iiivention, and in which like reference charac- 'ter's designate the same parts in the several views,

'7 Figure 1 is a front summon of a press em- 7 r to ig. 2 is also arrest elevation, being'a detail vieiv'of the lower part of 1, with certain o-fthe parts shown insection;

- Fig. 3 is a side elevation ofthe parts shown V Fig. 4 is a detail View of'the brake and its appurtenant elements ';and V Fig. 5 is-a detail top plan viem't'aken on the line 5'-5 of F ig. '1, showing the arrangement of the tripping dogs and'ioller. Referring now'to'thedrawings, and first to Fig. v1, tlie iiuineral 1' designates the side frame, 2 the upper cross inemben andfi the bed of a press, all bolted together in rig-id, 9 rectangular relation, and provided with le s a 4 to bring the; bed to a convenient height Upstanding side brackets 5,50; are secured to i the upper cross-member 2 end carry'bearings 6 forthe transverse'drive' shaft 7 which is continuously'driven by any suitable means,

as, for example, by the electric motor 8 through the medium of the belt 9 and pulleys 10 and 11. I 'i The upper cross member 2 is provided with a central hub internally threaded toreceive the threaded spindle 12 which carries the non-rotating compressing plunger 13. This plungeris preferably polygonal in section V and is adapted to reciprocate vertically in a slideway 14 secured between opposite portions of the side frame 1. Thebotto-m of the plunger 13 is faced to form the plunger head 15, and fixed to the upper end of the spindle 12 isthe horizontal wheel16, which is provided about its periphery with a suitable friction surface 17, as, for example, leather. Keyed on the shaft 7, on opposite sides of the horizontalwheel 16, area lowering disk 18 and a raising disk 19, a sufficient distance apart to enable them, when in the neutral position shown in Fig. 1, to berotatedjust out of contact with wheel 16. v j I It will be apparent that when the shaft 7 is l rotated the plunger head will be raised or'lowered, depending on which of the disks 18, 19 is brought into engagement with the horizontal wheel 16. I This alternative engagement is effected by sliding the shaft 7 axially in its bearings 6, whether manually 'or automatically/by the" mechanism which will now be described. Y The bracket 5a is provided witha horizontal arm 20 to afiord a fulcrum-for the bellcrank 21 which is forked at its upper end to embrace the sleeve 22 rotatably mounted on the shaft 7 but fixed against axial movement along said shaft. The bellcrank is linked by means of the rod 23 and adjusting .nuts24 to a hand lever 25 pivoted conven- 7 end of the shaft 7 to urge the raising disk 19 into contact with the horizontal wheel 16. This spring 26 operates, through the parts 7, 22, 21 and 23, to lift the hand lever 25 when released by the operator after completion of a downstroke of the plunger head 15, to bring the raising disk 19 into contact with the horizontal wheel 16 and thus raise the plunger head 15. j

One object of my invention is to provide positive and unfailing means for disengaging the raising disk 19 from the horizontal wheel 16 automatically as the plunger 13 approache the limit of its upstroke, and to so dispose such throw-off means that regardless ofthe' heightto which the inertia'of the rising parts,

EXCESS power of the motor 8, or any other cause may raise the plunger 13,the driving disks 18, 19, will be shifted only. to their neutral position and no further, thus posi-' tively preventing, on the upstroke of the plunger 13, engagement of lowering disk 18 with horizontal wheel 16. I providesuch means as follows Pivoted to the stationary upper cross member2 of the press is a bellcrank 28, one arni of which is slotted to receive a pin 29 on the rod 23. The other arm of bellcrank 28 is adjustable, as by means of a roller carried.

by an adjusting screw 30. It will be appreciatedj that lifting the rollerarm' of bellcrank 28 will result in shifting shaft? to the left (in Fig. 1) to throw disks'lS, 19, into their neutral position, and it will be further appreciated that if this li'ftingof the roller arm persists beyond a certain-limit, the shifting of shaft 7 to the left will like- 'wise continue, movlng the dlsks beyond their neutral position, thereby engaging lowering disk 18 withthe horizontalwheel 16,

In. order to cause lifting of theplungcr, regardless of the extent of the lift, to do no more than move the driving disks to-their 7 neutral position (in other words, to prevent excess upwardmovenient of the plunger from v causing engagement of lowering disk 18 with horizontal wheel 16), 1 provide an element movablewith the plunger, ada'pte'd'to' contact with the roller arm, of the bell'cr'ank 28, to

move the throw-off "means to disengaging position'during a portion of itscontact, and to effect no further movement of the throwas means during further'relative movement of the element and the throw-oifmeans' One form of such'element issl1own in Fig. 1, consisting of a stem 27 mounted on the plunger-18. and having at its upper end a ;surface inclined tofthe axis of the plunger.

When the risingplun ger approaches the limit of its upstroke this inclined surface contacts with the roller arm of bellcrank 28, thereby actuating the throw-off means to move the driving disks to their neutral or disengaged position; The side. of stem 27 below the inclined surface is formed parallel to the axis of the plunger, and this side contacts with the roller arm of b-ellcrank 28 during further upward movement of the plunger.v The stem is so proportioned, and screw 30 may be so adjusted, that contact of the roller arm with the straight side of thest em during-further traverse of these parts o'peratesto communi-V cate no, further movement to the power throw-off means, but serves only to maintain the throw-off means inits'disengaging position.

It will be appreciated that the mechanism just described effectually prevents the wearing of flat spots on the friction surface 17 of horizontal wheel 16 by preventing reverse insert directional engagement of lowering disk 18 with this friction surface during" the lift:- ing of the reciprocating parts of the press; 7

In'order to bring-the reciprocating parts of the press speedily to rest at theend of "the power 'throw-oii'nieans to'pla ce the driving disks in their neutralposition. Brake 31. it will be appreciated.- e'ngages wheel only after the driving disks are shifted into neutraL-"its function being solely to absorb the inertia of the upwardly moving and rotating parts. This brake is the type usually employed in presses of this character, and will not be particularly described, the detalls of its construction suificientl a earin in i n 4, which also makes clear the position in which it-is mounted with relation to the wheel 16 and upper cross member 2. I

;A guide 32.1nay be provided for thestem '27 to support the latteragainst the bending stress of bellcrank "28. This guide consists of short section of L-iron with one" web bolted to the centralhub of upper crossmeniber 2 and the other pro ectingtherefrom at 7 right anglesto afford a slide ioroneedge plurality of tiles.

of the vertical stem 2'7. i The die whi ch I have chosento show in the embodimentofinyinvention illustrated 111" the accompanylng drawings 1s one designed to produce at a singlepressing a It consists of a number of stationary plunge'rs 33 mounted on the press bed 3 and-a die case 34: properly apertnred-to receive these plungers. This die case 34 constitutes the upper element of a rigidrectangular frame whose lower cross member is designated 35, and whose side members 36 pass thronghthe bed 3, so that the rec-- tangular diecase frame is capable of easy reciprocation relatively to the bed of the press. H a Bolted to the under side of the bed'iis a frame 37, the lower part of which provides a cylinder containing the piston 38 whi'chis connected to the lower cross member 35 by the connecting rod 39. The latter passes out of the cylinder through the cylinder head 40, provided with theusnalair tight packing 41. An air valve 42 at the sideof the frame 37 has an air inlet 43 and upper and lower ports H and 45, by which air under pressure passingiinto the valve through the inlet 43 may because-d to lower and raise the piston 38. I

. The two-part die is therefore capable of assuming two positions. in Fig. l'the die is shown in its closed or stri'pped position, the

Fig. 2'shows the hexagonalffaces otthe die plunger's being flush with the surface of the die casexfiin Fig. 2ythe 'die'is shown in its open position, the die 'case being' raised above its position in Fig. 1-t0createpockets toreceive the ma- I terial' to be. compressed. I

It will he understood, more'over, that the position-of the die parts at any time will be determined by the position oithe piungers inthe valve 42, plished by the following means A Pedal 46 is fulcrumed'asa lever of the 1 second orderon a depending bracket, 47 'securedin-the rear ofthe valve 42,. and is connected to the valve rod ifibytho iinl: 49. A coil spring; 50 under tension between the pedal and press bed normally holds the pedal in its uppern iost position. ma nta ning; the double 'valve'plungers at the highest oi" their three possible positions, so that air under pressure is admitted through upper port lite depress thepi'ston- 38 and strip the die. hen it is desired toraise the-die case to creation-pockets tor'the dust, the material "which is to be compressed to torm the tile,

the pedal 46 is depressed. This lowers the valve plungers to their-lowermost positron,

admits-air under pressure through :lower port 41-5., and places the upperport-inconi munication -with the atmosphere, thus littactuation or whieh'is accoining' the piston 38 andIwith 'it the die case plungers' is one intermediateoftlie two just described. In this intermediate position both ports are in communication with the pressed. I

In eachfpressii'ig; operation the valve l2 must be placed successively in the three p0 sitions just described. aiiditis an object of my invention to provide means for the automatic actuation of the valve as the other parts ofthe press are put through their necessary movements. I accomplish'this purpose by certain-novel means which will now be described as the operation of the press as a whole is explained. i n ,The motor '8 being started so as to; turn therbelt- 9 in the direction indicated by the arrow, whatevermaybe the initial position of the raising andlowerin disks l9 and'18,

are at once brought to their neutral positlon, with, the horizontal wheel 16in its uppermost position. as shown'in Fig.1. An operator standing in front of the press then depresses the pedal 46, which brings the plungers' of the valve 42 to'their' lowest position and lifts the die'case 34, whereupon the dustis placed; in the pockets formed by'tlie parts-inf this'positionf T. 1e third'possible position of the valve The operator standing in front ofthe press thendepresses the hand lever to bring the lowering disk 18 into engagement with friction surface 17 of thehorizontal wheel 16,- and the plunger head 15 descends upon the die case. In order that the plunger head may compress the dust in the die pockets it is necessarythat-the die case beallowed to yield under pressure of theplunger head. Since in the 0 aeration of the press thus far described air pressure has been exerted against the underside of the piston 38, the plungers of the valve 4:2 must be movedto their intermediate position to placeportsd l and in communication with the atmosphere. This is done automatically as the plunger head .15 PflOVQStQWflNl the die, as follows: V

. Projecting horizontally from-one side of the top of the plunger 13 is an arm 51, carrying adepending bracket .52, upon which are mounted, instaggered relation, as appears inFig. 5, an upper dog53 and a lower dog 54. These dogs are pivoted as shown; and stop pins and small coil springs maintain them normally horizontal, the upper dog being free to swing down, and the lower dog being free to swing up. It will be notedthat the lower dog projects sli htly farther to the right than does the upper dog Thevalve rod'48 extends up as far as the slide way 14,

1 where it is pin-connected to one arm 'ofa bellcrank 55, which ispivoted to the slide way 14. The other arm of this, bellcrank carries a. roller 56 adapted to contact with the dogs 53 and From the foregoing description it will be clear that in the operation just described,

when the pedal is was'depressed to raise the die case, the roller 56 was drawn to its innerinost position. lVhen the plunger 13 began its descent, lower dog 52 rode over the roller 56 without altering the position of the bellcrank 55. lVhen,.ho'wever, upper dog contacted with roller 54, the bellcrank was moved slightly outward and there held by the upper dog 58, to lift the plungers of valve 42 to their intermediate position, the foot of the operator remaining on pedal 6 to oppose the lifting force of the spring 50 and hold the roller of bellcrank 55 against the upper dog 53. In this way only atmospheric pressure is exerted on both sides of the piston 38, andthe die caseis allowedto yield under pressure of the plunger head as he dust in the pockets is compressed.

l/V hen the compressing stroke has been completed the operator releases the hand lever 25, and the spring 26 pushes the r'"- disk 19 into engagement with surface 1"? of lower dog 54 has contacted with roller 56and moved bellcrank 55 to its outermost position.

move-the compressed product. Thev first operator may thendepress the pedal l6 to 'raise thedie case, dust is placed inthe die pockets, and all is in readiness'for a second pressing operation. I

lVhen presses of the character described areusedin the manufacture of tile, it is of great importance that, the finishedpro-duct be of uniform thickness. Of the several factors which principally affect the thickness of the tile produced by a given prcss the most easily controlled is the depth of the die pockets into which the dust is inserted. However, even if the pocket depth be kept uniform over a perio-dlof time, the tile have been found by experience to vary considerably in thickness, some of the causes of the variation being different consistencies of dust used, changes in temperature and humidity of the atmosphere, and wear of the parts of the press. Heretofore, in order to (affect adjustment of pocket depth when is noticed that the ti'leare running too thick orltoo thin, it has been'necessaryitostop the machine and take up on whatever adjusting means mayhave been provided, which gene I orally consisted'in moving the die case up or down on 1 the die side members. Besides necessitatmg that the, press be stopped, the

making of an adjustment of this kind is a matter of some nicety, requiring more skill than that usually possessed by the operator of a press, since the elevation of both sides of the die case must be exactly the same to maintain the'die case precisely perpendicular to the axes'of the die plungers.

It is an object of my invention to provide means for eii'ecting accurate and instantaneous adjustment of the depth of the pockets while the press is in operation, by the operator who stands behind the press and who, by this act of removing'the finished tile is bestable to observe anyyariation in their thickness. The .mea-ns which I provide eliminates the old adjustment of die case and side members, these parts being maintained in rigid relation with the lower cross member 35, but contemplates instead the provision of means to vary the upward limit of travel of the rectangular di'e'case frame.

One means of accomplishing this object is shown in the drawings. Referring especially to Fig. 2, 57 designates a rod fixed into the upper side of the piston 38 in alignment with the connecting rod 39 and projecting from the cylinder head through a suitable packingnut 58. Thisrod 57 constitutesa follower for the cam surface 59 of the cylinder 60 which is journalled transversely of the driving disks alternatively engageable With,

the horizontal wheel, throwpil-means for the driving disks, means cooperating with the plunger and the throwfofi means to place the driving disks in ,aqneutral position when the v plunger approaches the'lnnit of its upstroke,

and a brake operating upon the horizontal Wheel only after the driving disks are, placed in their neutral position; V V l ll, Ina'press ofthe character described, a compressing plunger, ahorizontal wheel adapted when rotated to" move the plunger,

, driving disks -alternati vely iengageable with the horizontal wheel, throwroll means forthe driv ng d sks ncluding a lever fulcrumed on the press, stem on the plunger adapted to contact with an arm of the lever asLthe plunger approachesthe limit of its upstroke'to place the driving disksin their neutral posi tion ,and a brake operating upon the horizontal wheel only after the driving disks are placed in their neutral position. v

1 2. In a press of the, character described,

a coin yressin linwer a horizontal Wheel b b i adaptedwhen rotated'to move the plunger, driving disks alternatively engageable with the horizontal wheel, a control rod for the driving'disks, a lever fulcrumed on the press with one arm pivoted to the control rod,.a stem. on the plunger adapted to contact with the other arm of the lever as the plunger approaches the limit "of its upstroke toplace the driving disks in their-neutral position, anda" guide on the press to support the stem against bending stress oi" the lever. 13. In a press of the character described. a compressing plunger, a h'orizontalwheel adapted when rotated to move? the plunger,

driving disks alternatively engageable with the horizontal wheel','a control rod for he driving disks, a lever fulcrumed' on the press with one arm pivoted to the control rod, a stem on the plunger adapted. to con: tact with the other arm of the lever as the plunger approaches the limit of. its upstroke to place the driving disks in their neutral position, and an inertia-absorbing brake operating upon the horizontal wheel only after the driving disks are placed in their neutral position.

1-}. In a press of the characterdescribed,

a compressing plunger, a lhorizontal wheel adapted when rotatedto move the plunger, a

raising disk and a lowering disk alternative ly cngagcable "with the horizontal wheel, manually controllable means for engagii'lg the lowering disk with the horizontal Wheel, means for urging the raising disk into on gagomcnt witlrthe horizontak wheel as the plunger 'is' driven"downwardly, means ac tuated by the plunger for Jlacing the disks in a neutral position as the plunger approaches the limitof its upstroke, and a brake operating upon the horizontal'vvheel 7 element.

nvedoiif only after the :driving arei pla c ed their nentral position. 1:

' I 15; A die consisting of a movable and a stationary member, an elemenc'earn d by the movable member, iafcam; carried b'y' the St tlonary member, and means foradpistlng the-.,cam to vary the limit of{ motion of the 16. Ar die consisting of the stationary memberf fo'r adjusting inseam to vary the limit of motion ot the element. p 7 v 17 A die consisting ofa movableand ia stationary member, anelement carried bythemovable member in. substantial alignment with'the center of area thereof,- a second ele inent carried by the stationary 'member adapted to be engaged by said first element during operation of the die, in combination :withmeansfor adjusting said second element to vary the ,limit of motion of saidfirst element. a V Y' Y V 18. A dieconsisting of a movable: and a stationary member, an element carried by themovable member, a second element carried by the stationarymember and :liavinga surface adaptedto be engaged by said first element-during operationof the die, in combination with means fixedly associated with the stationarymember and connectedWith the second element for adjusting. said second element tovary thelimit of motion of said first element. v V. I y, z

' 19. In combination with a presshaving' a plunger, driving means i for moving said plunger on its working stroke and other drivoff means'adapted to be moved to disen aging position whereby said plunger is rendered inoperable vby both of said driving means,

and means for actuating said throw-01f ,means comprising an element movable synchronously with the plunger and in contact with said throw-off means, said element .be ing adapted by said contact to move said throw-off means to its disengaging position regardless of the extent of continued relative movement of said element and said throwoff means after the beginning of said contact.

gaging position, and during the remainder a movablejand a stationary member, an element carried by the movable vmember,-a cam carried by the sta-' tionary member, and means associated with lng means for retracting'said plunger, throw H of its contact to. communicate no further movement to said throw-off means;

21. In combination with a press having a ,7

plunger, driving means for moving said plunger on its working stroke andother driving means for retractingsaidiplunger, throwofl means adapted to bemoved to disengaging position whereby said plunger is rendered inoperable. bytboth of said driving means, and means for actuating said throw- 011? means comprising an element movable synchronouslywith the plunger to traverse sa d throw-off means, said element being adapted during said traverse to move said throw-off meansto its disengaging position,-

and during the remainder of its traverse to maintain said throw-ofl' means in its disengaging position.

22. A press including a plunger, a horizontal wheel adapted when rotated to move the plunger, driving disks alternatively engageable with the horizontal wheel to raise and lower the plunger, in combination with" power throw-off mechanism including means and adapted in one position to disengage said associated with the driving disks disks from saidhorizontal wheel, and a member associated with said plunger and movable synchronously therewith having a surface adapted to be engaged withsaid means, one portion of said surface being adapted to move said means to disengage said disks from said horizontalwheel, and another portion of said surface being adapted to maintain said disks disengaged from said horizontal Wheel.

23. The combination claimed in claim 19, in which the throw-off means is a pivoted element, the means for actuating the throw-off means is a stem mounted on the plunger, and the surface of the actuating means adapted to contact with the throw-ofi-means is in part inclined to the axis of the plunger and in part parallel therewith.

24v The combination claimed in claim 19, in which the throw-off means is a bellcrank pivoted to a stationary part of the press, and

the means for actuating the throw-off means is' a stem mounted on the plunger and adapted to be moved by the plunger into contact with an arm of the bellcrank, the portion of the surface of the actuating means first adaptedto contact with the arm of the bellcrank "being inclined to' the axis of the plunger, and the remaining portion of said surface adapted to contact with the arm of the bellcrank upon further movement of tho plungerbeing parallel to the axis of the plunger.

25. The combination claimed in claim 19 1n comb nation with a member movable with said plunger anda brake adapted to engage said member after said throw-01f means-has been moved to its disengaging position.

In testlmony whereof I afiix my signature.

DAVID CROSSLEY.

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