US2789437A - Drive apparatus - Google Patents

Description

DRIVE APPARATUS 3 Sheets-Sheet 2 Filed May 11, 1955 INVENTOR.

April 23, 1957 w. FQ LoNGFlELD DRIVE APPARATUS 3 Sheets-Sheet 5 Filed May 11, 1955 IN V EN TOR. W/L/AM LONGF/[LD BY Attorney DRIVE ArPARATUs William F. Long-field, Warren, Ohio, assigner to The Fed` eral Machine and Welder Company,:WarrenOhio, 'a

corporation of Ohio Application May 11', v195`5, "S`e'i'al N0. 5

7 Claims, (Ctr/4444) The present invention relates nto drivev apparatus, more particularly to' apparatus for effecting twospeed operation of a press o'r other device, and the principal object of the invention is to providencw and improved apparatus of the character described. v

As is well-known in the art, high speed operation of drawing presses and the like is limited by the fact that the drawing operation cannot be accelerated beyond a certain rate of speed without tearing the material being drawn. In the past, attempts have been made to increase th'e production of drawing presses by operating them at their optimum speed during the drawing portion of the press cycle and` at a higher speed during theyother portions of the press cycle preceding and subsequent to the drawing portion. This theory of operation has proven practical; however, it is believed that the prior art 'mechanisms devised for this purpose have not been entirely satisfactory.

One of the earliest attempts to accomplish multiple speed operation ofv presses andthe like 'is-l disclosed in Patent No. 1,060,662 issued to Bauroth. The ca'm mechanism disclosed in this patent extremely'f-bulky and is' unsuit'ed for high'speed operations and/ or heavy duty, long stroke presses.

A later approach to the problem is disclosed-ih Patent No. 2,073,239 issued to Byerlein ',Th e Byerleinconstruction is' more practical than that'v of B auroth; vhowever, Byerlein requires' cumbersome reduction gearing which'is noisy and is troblesonreto maintain since the" gearing is subjected to considerable shock, Moreover, since the speed ratios of the Byerlein ydevice are established lby gearing, changing suchfratios requires that the heavy reduction gearing be changed. This, it will be understood, is an expensive, time consuming operation.

The present invention possesses none vof the `disagi; vantages of the prior art deviees mentionedand since it employs a novel principle of operation which utilizesonly that gearing vfound necessary in ordinary, single speed presses, it is easily' adapted to conventionalpress designs. Other advantages will readily become apparent from a` study of the following description and from the drawings appended hereto. 'In' the drawings accompanying'- this specification. and forming apart of this application' there is shown, for purpose of illustration, anembodimen't which the'inven# tion'ma'y assume, and in these' drawings:

Figurel isa front elevational view 'of' a pressentbo'dy'ing' tliepresen't'invention,

`,Figure 2` is' a top planview,

'Figur'es3' and 4 are enlarged,` complementary.vievvs'f ,W n65 joinedtogether at the brealcdinev to form the; :o1"npl 'etedl taken along line x-'-x' of Figure 2 andadapted t'o b'e section; and

Figure 5 is' a schematic diagram of c'onibination electrical-iluid circuit found= suitable for' controlling operation of the invention and for'ccordinatin'g'itsoperaiJ tion with the-press with whichit isjemployed;l

' speed is desirousl ice A 2 employed with a drawing press, it is to be 'clearly under-l stood that this use is illustrative only and' that the iuvenf' tion may be advantageously employed with any other suitable apparatus whose' operation at "Figure 1 illustrates a conventional fpressfl0havingja v rewcfiprocable slide l 1 'connectedtq a 'cr an ks haft 12 b'y' means of a connecting rod 1 3. The crankshaft '12.is suit- "alirly` journalled .inf' the frame of th e press ,andi rotation of the former -reciprocates the slide 11 toward and, away fro'rn the bed 14 of the press.; AlthoughnQt '-'showm'th'e fb'ed 14 may carry one'part of a f91l1lig .dif '\vhilfthe' slide 11 may cairy a complementary/ part jofr the die.;A Se: cured to onek end vof crankshaft 12 is a bull gearv 145 which is adapted eshwith a suitable driVef pinion which, in conventional single speed press constructions, is usually carried" by a suitable lcountershaft.A The countershaft usually carries a flywheel for storing energy and the countershaft `is adapted to berotatedV by any' suit'f` able'ineans.

In the embodiment ofthe, invention herein disclosed,` the conventional countershaft is replaced by a drive'- sh'aft 16 mounted on the press by means of suitable brackets 17, 18. Shaft carries a. drive pinion -19jwhich m'e'sh'es with bull gear 1 5 and, in the' present'construcf" tion, brackety 18 provides a't least a partial guard for the'gears. .N AsI best shown in Figures 3 ar1 d 4, housing l17 rotatably support the' shaft 1 6 by means o f an anti-jfrictio-11I bearing 20 while housing 1 8 rotatablysupports the "shaft by means of amantifriction bearing 21.5 I n thepresent embodiment, shaft 16' supports Va* pair o f spaeed' ywheels 22, y23 eac'h'nof which-is' independently vrota t' 1 ble Awith respect to the' straft.'V The -flywheels are-.adaptedjtofb' rotated at different.spee'l'al means later to be disclosed',- and each is preferably ofahdilferent'size,

Secured yto ilywheel 2 2 (see Figure` 4) gby suitable bolts', are axially 'spa'cedlapartnd Walls 2 4, 2 5 and" an. in'ter'nled iatev wall End'fwal-llly is rotatably mounted en shaft 16'by 'means of abearingl27 whileintermediatewall 2 6 is mounted o'r i' tl ie'- shaft bymeans of ,a bearing 2s. shaft 16 'terminates' intermediate wausgzs, 26.for a purpose "to bec'onie clear. End `wall 25 is formed" to p r'ovide yan inwardly facing cylinder portion 29 in which aQpiston` member' 30 `having a transverse face 31jis' reciprocable axially lo f thel shaft. Means arei provided -32 and end wall 2 5 toyieldably urge the terial. For a purposeto be seen, the youter periphery of disk M is formedto provide teeth, or sp lines, j whichnie'sh with teeth formed in' the inner periphery of airing member 36 secured"t o end v'v'all 25 by,mean s of bolts 37. This construction locks disk 34 agai n st rotation :relative to' the tlywheel but permits the disk a limited amount ofaxlial movement.' In'oder to reducethe numbei' or different parts, disk 35 is sirnilar to disk and 1 isi'rnount'ed in a similar manner (but against intermediate wall 426) ever1 though it is'unne'ces'sa'ry to provide for axial movement of this disk.

more than one' l having* axiallyIsraicge'ii,A oppositely facing surfaces avea-tsv' ber 38 has an inner periphery formed to provide teeth, or splines, which mesh with teeth formed in the outer periphery of a collar 39 securely keyed to the adjoining end of shaft 16. Accordingly, friction member 33 is locked to shaft 16 for rotation therewith but is movable axially of the shaft for reasons to appear.

End wall 25 provides a passage 40 which communicates with the interior of the cylinder formed by portion 29 of this wall. A suitable conduit (not shown) connects passage 40 with a fluid control valve later to bedescribed, any-suitable swivel connection being interposed between the-conduit and end wall 25 to permit the flywheel to rotate relative to the conduit.

Operation of flywheel 22 and the above-described clutch mechanism carried thereby is as follows: Assuming that flywheel 22 is being rotated by means later to be disclosed and that the parts carried by the flywheel are in the position shown, shaft 16 will remain stationary since disks 34, 35 are out of engagement with friction member 38. If fluid under pressure is now admitted to thefcylinder formed in end wall 25, piston member 30 will be shifted to the left against the resiliency of springs 33. Disk 34 and friction member 38 will also'be moved axially to the left until the friction member is tightly clamped between the two disks 35, 34. This will lock flywheel 22 and shaft 16 together and thus cause the shaft to rotate with the flywheel.

Shaft 16 will be disengaged from flywheel 22 by exhausting the fluid from the cylinder provided by end wall 25. This will permit springs 33 to move piston 30 to the right to thereby effect disengagement between friction member`38 and disks 34, 35 and thereupon permit the flywheel to rotate relative to the shaft.

' Referring now to Figure 3, flywheel 23 is similar to flywheel 22 (with the exception of size). Therefore, corresponding parts are identified by the same reference characters but with the suffix a added. Because of its size, flywheel 23 requires more support than does flywheel 22; accordingly, end wall 25a is provided with an outwardly directed axial extension which provides a stub shaft 41 coaxial with shaft 16 and rotatable in a bearing 42 carried by a bracket 43 secured to the press frame. Since the left side of flywheel 23 is rotatably carried by bracket 43, intermediate wall 26a is not sec ured directly to shaft 16 as isintermediate wall 26. Instead, wall 26a is apertured at 44 to pass shaft 16.

To facilitate assembly and disassembly by maintaining flywheel 23 generally in alignment with shaft 16 while bracket 43 is being installed or removed, aperture 44 is only slightly larger than shaft 16 so that the intermediate wall 26a can support the left end of the flywheel at such times. Since the clearance between wall 26a and shaft 16 is slight, a ring 45 of suitable bearing metal may be interposed between the wall and the shaft 4to protect the shaft against possible damage.

Securely keyed to shaft 16 intermediate flywheels 22, 23 is a drum 46 against the periphery of which a brake shoe' 47 is adapted to bear. As generally diagrammatically shown in Figure 3, brake shoe 47 is carried for movement toward and away from the drum by the piston 48 of a fluid cylinder 49. The brake shoe is preferably resiliently biased to engagement with the drum by any suitable means such as by means of a spring 50 interposed between the shoe and the cylinder. A conduit 51 connects the rod end of fluid cylinder 49 with a source of fluid pressure as will later be disclosed.

As previously mentioned, each flywheel 22, 23 is adapted to be independently driven and, in the presently disclosed embodiment and as best shown in Figure 2, separate motors are employed to drive the flywheels. Flywheel 22 is adapted to be driven by an electric motor 52 while flywheel 23 is adapted to be driven by an electric motor 53. It is preferably to connect motors 52, 53 with their respective flywheels by means of drive belts 54 running in grooves in therespective tlywheels and over suitable sheaves carried by the motor shafts. This type of drive eliminates noisy gears and tends to reduce shock because of the resiliency of the belts. Moreover, in the event it is desired to vary the speed rat-io between the flywheels, it is only necessary to change the size of the sheave on one and/ or both of the motor shafts. While the present embodiment employs two drive motors, it is to be clearly understoodthat a single motor could be employed to drive the llywheels. For example, a motor having a shaft extending from each end could be employed,y each shaft 'extension being adapted to drive a respective one of the tlywheels.

In theembodiment herein disclosed, drive motors 52, 53 operate at generally the same speed; accordingly, since the motor sheaves are the same size, while flywheel 22 is materially smaller than flywheel 23, the latter flywheel will be driven at a slower speed than will flywheel 22.

Referring to schematic diagram, Figure 5, there is shown a camshaft 55 which is movable in accordance with movement of the slide 11 of the press. Camshaft 55 may be driven by any suitable member which moves in a fixed ratio with the press slide. For example, the camshaft could be connected to crankshaft 12, drive shaft 16, or even driven by motion of the slide itself, the only requirement being that the camshaft rotate (at least in the present embodiment) one revolution for each stroke of the press. For a purpose to be pointed out, camshaft S5 carries an interrupter cam 56 having a lobe 57 and a speed control cam 53 having a lobe 59.

`A spring biased, sloenoid operated, fluid valve having an inlet, an outlet and an exhaust is connected to a spring biased, solenoid operated, fluid valve 61 having an inlet, an exhaust and outlets A and B. The outlet of valve 60 is connected to the inlet of valve 61 by means of a conduit 62 while conduit 51 connects conduit 62` with brakecylinder 49. The inlet of valve Y6i) is adapted tobe connected to a source of fluid pressure while outlet A of valve 61 is adapted to be connectedv to the interior of the clutch cylinder carried by flywheel 22 and outlet B is adapted to be connected to the interior of the clutch cylinder carried by flywheel 23.

The solenoid actuator of valve 60 is connected across power Vlines L1 and L2 by means of a circuit 63 which includes normally open contacts 64 of a relay 65 and normally open contacts 66, 67 of respective actuating switches 68, 69. The actuating coil vof relay is connected across the power lines by means of a circuit 70 which includes normally closed contacts 71, 72 of respective actuating Aswitches 68, 69. A shunt circuit 73 is provided around contacts 71, .72 through normally open contacts 74 of relay 65 and through the contacts of a normally closed switch 75 which is adapted to be i opened by lobe 57 of cam 56. The solenoid actuator cause valve 60 is (le-energized, and in this position, the' llet B of valve 61 will be in communication with the exhaust of rthis valve while outlet A will be in communication with the inlet sincethe valve is de-energized. No fluid will flow to the clutch of flywheel 22, however, be-

inlet is blocked from the outlet and the latter is connected to exhaust. When the valve 60 is de-energized, the cylinder 49 is also connected to exhaust by reason of its connection to the outlet 62 of valve 60, so that spring 50 holds the brake applied to shaft 16 and thus holds slide 11 -of the press in its uppermost position, as herein disclosed, or in any pre-selected position depending upon the angular adjustment of cam 56.

-Assuming that drive motors 52, 53 are running, the

operator may close a switch (not shown) to establish I flow of current throughl lines L1 and L2, which inturn will cause current to flow' through relay 65 via 'circuit 70. .andnormallyaclosed contacts `7 1, 7 2rof-factuating switches 68,169. Flow. ofi-.current `thrQl'Igh-the relay wlll closedcontacts 64 in .circuitlf63 and contacts y74 in-circuit 73. Since contacts66, 67 of switches 68,-69 arenormally open, no current will ow through-circuit 63 vat this time so that valve '60 will remain de-energized. \Note that losing of contacts 74 will ca-use current to ow through shuntcircuit 73 to thereupony hold relay 65 energized.

For safety purposes, it-is necessary. thatthe operator depress both switches 68, 69 in :order to effectoperation of thepressand, normally, the yoperator will be required to. operate one of these switches with one hand and the other switch with ythe other hand'.- .-Whennthe operator closes both switches 68,:69,` contac"ts 71,` 72 will be opened; however, since shunt circuit .73 ist-completed, :relay 654 will remainenergized. rClosing switchesv 68, 69 will close contacts 66, 567 wandcurrent will therefore flow through circuit 63 Ato energize solenoid valve/60. When this valve is energized, its outlet willQbej-placed in communication withitsinlet and fluid underpressure will thereupon ow to the inlet of valve 61Vvia'conduit162. Since valve 61 is not energized at this time, `tl'uid will ow through the valve from its inlet toaoutlet 'A and thence to the c lutchy carried by ilywheel 22.v

yFluid will also ow to cylinder 49 thus withdrawing brake shoe 47 from engagement with drum 46. Flow of fluid to the clutch carried by flywheel 22 will engage this llywheel with shaft 16 andy thus eiect rotation of this shaft and downward movement of slide 11 as before described. Since flywheel 22 is rotating at a relatively high speed, slide 11 will move downwardly at a relatively high speed and, as before described, camshaft 55 will be rotated in the direction of the arrow (Figure in synchronization with the slide.

As slide 11 approaches the working portion of its stroke, lobe 59 of speed controIcamSS will 'close the contacts of switch 77` Vand thereupon energize solenoid valve 61. Energization lof va1v`e-f61 will connect outlet A with the exhaust to release thesclutch carried'by'ywheel 22 and simultaneouslyaconnect outlet B with the inlet to engage the clutch carrie'djby flywheel 23. With flywheel 23 engaged with shaft 16-the slide will progress at a slower speed so that` the proper-'drawing action can take place. .Us

At the completion of thefdrawingoperation, camshaft 55 will have rotated sufficiently thatl lobe 59 of cam 58 will no longer hold the contacts vof switch 77 closed. This will deenergize solenoid'valve 61 and once again engage the clutch carried by :ywheel 22 and disengage the clutch carried by flywheel 23. vAccordingly, slide 11 will once again move at high speed.

As the slide approaches itsauppermost or other preselected stopping position,l'obe 57 of interrupter cam 56 will momentarily open the contacts of switch 75. This will break shunt circuit 73 and de-energize relay 65. Deenergization of relay 65 will open contacts 64 in circuit 63 and contacts 74 in circuit 73.4 With circuit 63 open, solenoid 6ft will be de-energized to close this valves inlet from its outlet and to connect its 'outlet to exhaust. This will disengage the clutch carried by flywheel 22 and also permit spring Si) to apply the brake to shaft 16 to thereupon stop the slide at the top of its stroke.

It will be noted that although the contacts of switch 75 are only momentarily broken, relay 65 will remain de-energized until such time as the operator releases both actuating switches 68, 69 to permit the latter to return to the position shown in the drawing. Only when the latter occurs, will relay 65 be re-energized to prepare the circuits for the next cycle which will commence when switches 68, 69 are once again depressed by the operator. Accordingly, it will be understood that the hereindisclosed apparatus provides for onestroke, non-repeat operation of a press or the like at relatively low speed during part of the press cycle and at relatively high speed during the remainder of the cycle,

vention possesses considerable flexibility-ankliitsistoibefl noted that one or the other of the llywheel'drivesmv be employed alone to operate the pressinaconv'entonl' manner and to permit repair of one of the gdr'iveswithot stoppage of production. l I In vew of the foregoing .it will; be kapparents"to those skilled in the art that -I have accomplished fat-least the principal object of my invention and Sit willalsof-he parent to those skilled in the artztha't 'thev ernbiciirneiit'- herein described may be variously changed and.

without departing from the spirit -of theinlvetion, and,

that the invention is capable of uses and has jadvantge'sf not herein specifically described,;h'enceA Tit'I \iJill.-l:zap" y preciated that the herein disclosed embodiment isl illus'- trative only, and that my inveritionds not limited't-heretb'.

I claim: g Y l. A powerV press having a. reciprocable slide,fa'c"rank shaft having drive connection with said slide .to effect:

reciprocation thereof, a shaft rotatably supportedby'said press and having driving connection `with said'lcrankf" shaft, a pair of iywheels, eachvof lconsiderablemass and.

eachmounted on said shaftl for rotation-relative-theret, means for rotating said ywheels on said shaftone y1- wheel rotating at a greater speed than the other; andy clutch means for said flywheels and .selectively operable'- to engage one or the other of said ywheelswithf'said shaft and thereby provide rotation of said-shaft and'conw-K: sequent rotation of said crankshaft and-'reciprocation of.

said slide at a speed governed bythe engaged flywheel;

2. A power presshaving a reciprocable` slide, avcrankshaft having drive connection with said slide to effect reciprocation thereof, a shaft rotatably supported` by said press and having driving 'connection with said. crankshaft, a pair of flywheels of dilierentY diameten, eachA mounted on said shaft for rotation relative thereto, means. l

for rotating said ywheels on said shaft and-constructed and arranged whereby the larger ywheelis driveniax' a lower rotational speed, Iand a clutch for :.each'offsaid tlywheels and selectively operable to engage-arespective'-I tlywheel with said shaft, whereby said crankshaftis rof tated and said slide is reciprocated selectively atfsjpeeds governed by the speed of the engaged llywheel.`

3. A power press having a reciprocable slide, a" crankshaft having drive connection with said slideto effect reciprocation thereof, a shaft rotatably supported by said press and having driving connection with said crankshaft, a pair of iiywheels mounted on said shaft for rotation relative thereto, drive motor means for said flywheels, belt and pulley connections between said drive motor means and said ilywhecls whereby said lywheels may be rotated at different speeds, and clutch means for said ywheels and selectively operable to engage one or the other of said flywheels with said shaft and thereby provide rotation of said shaft and consequent rotation of said crankshaft and reciprocation of said slide at a speed governed by the engaged ywheel.

4. A power press having a reciprocable slide, and means for reciprocating said slide, including a pair of rotatably mounted flywheels of different diameters, a separate drive motor for each of said lywheels, each drive motor having a pulley on its driving shaft and a belt engaged over such pulley and over the periphery of a respective flywheel whereby said pulleys may be related in size to drive the larger flywheel at a slower rotational speed, and a clutch for each of said ywheels and selectively operable to engage a respective flywheel and thereby provide for reciprocation of said slide at a speed governed hytheengaged ywheel.

. A Y. 7 f5. A drawing press having a stationary die supporting pprtirmA and a. reciprocable die supporting portion movable' v"through'a cycle at one speed during drawing operation and aty a higher speed preceding and subsequent to said drawing operation, comprising a pair ofrotatably mounted flywheels, one rotating at a higher speed than the otherclutch means for said ywheels and selectively operable to engage one or the other of saidywheels and establish a drive connection with said reciprocable diesupporting portion, and control means operable during selected portions of the cycle of said reciprocable die supporting portion to engage said clutch means with the slower rotating ywheel during the drawing'operation of said press and to disengage said clutch meansfrom said slower flywheel and engage said clutch means withthe faster rotating ywheel during the time preceding and subsequent to said drawing operation.

6'.v Adx'awing press having a stationary die supporting portion and a reciprocable die supporting portion movable through a cycle at one speed during drawing operation and at'a higher speed preceding and subsequent to saiddrawing operation, comprising a pair of rotatably mounted ywheels and means for driving said lywheels, olie flywheel being of greater diameter than the other and'rotating at a slower speed, a clutch for each of said ywheelsrand selectively operable to engage a respective y'wheel'and establish a drive connection with said reciprocable die supporting portion, and control means pera'blefduringselected portions of the cycle of said reciprocable die supporting portion to engage one clutch with the larger and slower'rotating ywheel during the drawing operation of said press and to disengage said one clutch and engage the other clutch with the smaller and faster rotating flywheel during the time preceding and subsequent to said drawingoperation.

7. A drawing press having a lstationary die support` ing portion and a reciprocable die supporting portion movable through a cycle at one speed during drawing operation and at a higher speed preceding and subsequent to said drawing operation, comprising a shaft rotatably mounted on said press and having driving connection with said reciprocable die supporting portion, a pair of ilywheels of differentdiameters, each mounted on said shaft for ro-` portions of the cycle of said reciprocable die supportingv portion to operate the clutch associated with the larger and slower rotating ywheel to engage such ywheel with said shaft during the drawing operation of said press, and being operable to operate the other clutch associated with the smaller and faster rotating flywheel to engage such ywheel with said shaft during the time preceding and subsequent to said drawing operation while rendering said rst clutch inelective.

References Cited in the le of this patent UNlTED STATES PATENTS 2,488,892 Arzt Nov. 22, 1949" 2,557,896 Soule et al. June 19, 1951 2,577,641 Wissman Dec. 4, 1951 FOREIGN PATENTS Great Britain Oct. l5,

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