US2317440A - Press - Google Patents

Description

April 27, 1943.

E. CANNON PRESS 32 as 34 I 35 4 iNVENTOR 6 m w BY 9 A ORNEM mm W w km S o 7 A Z! NM m w 4 a mm fix b n w wm 2 m F G Q .w. AH JUN 0 1.11 o o lw. @r E 1 H A rii 27, 1943.

E. CANNON April 27, 1943.

PRESS Filed Feb. 25, 1941 8 Sheets-Sheet 5 has HM wax b U QQN NNN

k u 3m DWN INVENT R om m BY M E. CANNON April 27, 1943.

PRESS Filed Feb. 25. 1941.

8 Sheets-Sheet 6 A rij 27, 1943.

. E. CANN ON PRESS Filed Feb. 25, 1941 8 Sheets-Sheet 7 W QQN April 27, 1943. E. CANNON PRES S Filed Feb. 25, 1941 8 Sheets-Sheet s QMNQDNU swga v "WI-1125 ORNE Patented Apr. 27, 1943 4 PRESS Earl Cannon, Rockville Centre, N. Y assignor to E. W. Bliss Company, Brooklyn,

ration of Delaware N. 22, a corpo- Application February,- 25, 1941, Serial N... 330,493

35 Claims.

This invention .relates to improvements in presses, and more particularly to that type of press wherein a die, having the shape and contour of the articleto be formed, is used with a pressing member adapted to coact with said die in the pressingoperation, the contour of which member, however, is not complementary to the contour of said die but is in the form of a resilient pad which, underpressure, will engage a blank to be processed and press it into the said die to give the blank the desired form of finished article or to give an intermediate form to the blank so that it may, by subsequent operations, be processed into its final form.

The invention is particularly. useful inindustries wherein the output of products is relatively low in number but the parts going into such products are of a large variety of sizes and shapes. In the production of a single plant in such an industry the total number of completed products put out in a period of time may be relatively low, and each completed article produced might comprise one or only a relatively few of each of a large number of parts of difierent sizes. and shapes; Although the present invention may be useful in numerous industries, the production problems in the aviation industry serve to illustrate the need for the invention. -Any given plant in that industry might produce, say, 100

planes per month. In each of those planes there would be hundreds of parts of different sizes and shapes, and each completed plane might possibly embody only one or two of each of such parts. Thus, to satisfy the requirements of one months production in that plant, it would be necessary to make only 100 to 200 of each of those parts per month. Ihe present invention is considered to be particularly valuable in solving production problems of this character, namely, the production of a large total quantity of numerous parts while producing relativelyfew of any one part.

Many parts going into'completed products are formed by pressing relatively thin and easily deformable material into the desired shapes. If, in producing such parts, the press used-is one which accommodates only a single die or pair of dies, it would be necessary to change the dies in the press many times in producing the variety of parts constituting the plants requirements for a given-period of time, such as two weeks or a month. Such a press could be operated quite rapidly only if the dies used therein were designed to produce only one part or an extremely limited number of parts in a single pressing operation. If it were attempted to employ a single multiple dieor a pair of multiple dies adapted to produce a number of different parts therefrom in a single pressing operation, it would probably take one or more operators considerable time, possibly from five to fifteen minutes, to load the die with the proper blanks for each operation,

and during the period of that leading operation. the press itself would be entirely inactive. On

the other hand, if the die used were one which would form only one or two parts in each pressing operation, it would be necessary to change dies many times to produce the numerous'different parts required.

An important object of the present invention is the provision of a press having a plurality of die-carriers which may be substituted rapidly for each other, so that, while a die on one carrier is being loaded by one or more operators with the proper blank material, the blanks loaded by other operators .onto dies on other carriers may go through the pressing operation, thus keeping the press in substantially continuous operation and affording substantial economy in the production of small numbers of each of a large number of different parts.

-' Another object of the invention is the pro vision of means whereby the various die-carriers and dies thereon, loaded with blanks, may be moved into the press for the pressing operation while avoiding any interference of two or 1 more dies with each other during the substitution of dies.

Another object of the invention is the provision of a press having a plurality of radially movable, interchangeable die-carriers and a resilient pressing member for coacting with a die on any one of said die-carriers in a pressing operation, and means whereby the action of the diecarriers and the said pressing member is so interrelated that, although the die-carriers move into and remain in the press in diiferent radial 1 positions, the pressing member, however, is

caused to automatically move to a position cor-v responding to the position of whatever die-carrier is in the press, so that the proper coaction v 7 between the die on said carrier and the pressing v member may be attained. Still another object of the invention is the provision of means by which the action of the press in closing and opening is interrelated to the action of the several die-carriers and the I movement of the pressing member, so that the desired coaction in the operation of the said parts of the press during apressing operation'is' obtained.

Another object of the invention isthe pro- Another object of the invention is the provision of operating means for the press which are substantially automatic, and still further objects and advantages of the present invention will be perceived from thefollowing specification and the accompanying drawings.

The objects and advantages of the present invention may be attained in a press having a plurality of die-carriers, radially arranged in a common horizontal plane, each adapted to be moved radially, with a die thereon, to a central point where it may rest upon the bed of the press, and having a pressing member in the form of a resilient pad disposed coaxially relatively to the bed of the press and adapted to coact with a die on any one of said carriers which may be positioned upon the bed of the press, in order to, perform a pressing operation.

Inasmuch as several of the radially arranged die-carriers in such a press would be disposed in different radial positions when resting upon the press-bed, the resilient pad is preferably mounted in such manner that it may be rotated to the several radial positions corresponding to the positions of the several die-carriers, so that itmay properly coact with whatever die is in the press.

The dies and die-carriers which support them are preferably rectangular in shape and somewhat elongated, so that several operators may conveniently work together on each die to load it with blanks. The size and shape or the resilient pad should preferably be substantially the same as as an indication that the invention is to be limited to this disclosure.

The embodiment of the invention disclosed herein, for illustrative purposes, is shown in the drawings, in which:

Figure 1 is a perspective view of a hydraulic press embodying the principles of the invention.

Fig. 2 is a plan view of the bed of the press showing three of a plurality of die-carriers. The remaining die-carriers are similar to those shown but are omitted to permit suitable enlargement in order to show details more clearly.

Fig. 3 is a horizontal section looking upward on the line 33 01 Fig.- 1, showing the mounting of a holder for a'resilient pad Dressing member and showing also certain means aflectlng the rotation of said pad-holder.

Fig. 4 is a vertical side elevation oi the main press slide, being broken away to a considerable extent to show in vertical section a pad-holder, a turntable -or dial upon which it is mounted. means by which the turntable is rotatably mounted upon said slide, and also a motor for rotating said turntable.

Fig. 5 is a vertical sectional view of yieldable die-carrier supports which may b provided in 'the bcd of the press.

Fig. 6 is a side elevation of a die-carrier and its support, and a motor for operating said diecarrier.

Fig. 7 is an end elevation of a die-carrier as viewed-from the right of Fig, 6, partly broken away to show the arrangement of rollers upon which said die-carrier, moves.

Fig. 8 is a vertical, transverse section on the irregular line 8-4 of Fig. 6. Fig. 9 is a detail view, in vertical section, oi a .die-carrier supportingroller.

the dies, and said pad should preferably be mounted within a box-like structure, the side walls of which may iunction to restrict the outward flow of the resilient material or the pad under pressure, for, unless such outward flow is substantially restricted, the pressing eil'ect of the pad in coaction with the dies would be unsatisfactory in many, if not all, instances. Thus arises the necessity of rotating the resilient pad trom time to time in order that its position may coincide with the position of the die with which it is next to perform a pressing operation.

The several die-carriers may be moved into and out of the press by suitable motors, such, for example, as electric motors, the controlling circuits of which are preferably so interrelated that only one die-carrier may be moved into the press ata time. The resilient pad, likewise, may be rotated by a motor, such as an electric motor, the circuit or which may be adapted to cause said motor'to turn said resilient pad either to the right Or to the left to a sumcient extent to bring the pad into mating relationship with av substitute dieafter one die has been moved out of the press.

The objects, advantages and results, hereinbefore briefly summarized, may be achieved in a structure as described hereinafter in this specification and illustrated in the accompanying drawings, it being understood, however, that this description and the said drawings are employed only for illustrative purposes and should not be taken Figs. 10a and 10b are explanatory diagrams of certain electric symbols employed in the wiring diagram shown in Figs. 11a, 11b, 11c and 11d.

Fig. 11a is a first portion of an electric wiring diagram adapted foroperating and controlling the press illustrated and described herein.

Fig. 11?) is a second portion 'of said wiring diar Fig. 11c is a third portion or said wiring diagram.

Fig. lid is a fourth portion of said wiring diagram.

' It will be helpful in gaining an understanding bi the present invention to observe that Figs. 11b, 11c and 11d are continuations, respectively, of

' Figs. 11a, 11b and 11c, and that when so arranged the principal circuits begin and end at substantiallydirectly opposite points in the diagram. Where this could not be arranged, the circuits have been extended, where possible, almost to such opposite points, and then, where necessary, have been carried into other related circuits. The press shown in the drawings is a hydraulic press having a base II and a crown 22 fixedly held together by tie-rods 23 in a well understood manher. A main press slide 24 may be secured by bolts 25 to the lower end ore. ram 2.,as best seen in Fig. 4, and may be arranged to slide vertically upon the tie-rods 23, suitable bores being provided in said slide to accommodate said tie-rods, and suitable bushings 21 being provided within said bores and extending about said tie-rods.

As is well understood in the art relating to hydraulic presses, the ram 28 is adapted to receive hydraulic pressure at its upper end to move it and I the slide 24 downwardly to perform a pressing operation. The return orupstroke of the slide 24 may be accomplished through the medium of pistons 28 adapted to be pushed upwardly by hydraulic pressure applied at their lower ends, which upward movement is transmittedthrough cross-head 29 to pull-back rods 30, and thence to the main slide 24 into which said pull-back rods.

are screwed or otherwise fixedly secured. It will be observed that the pull-back rods may pass through suitable bores in the crown 22, as illus trated, and may be secured at their upper ends to the cross-heads 29 by nuts 3 I.

The press illustrated in the drawings is a sixsided press. A flat, horizontal bed 32 is provided 'upon the base 2|, and six die-carrier runways 33 l, to an operative position wherein its center is substantially in vertical alignment with the center of the bed 32. In'the last-mentioned'position a die (not shown), supported on the die- 7 carrier, will be in a position to coact with a pressing member carried on the underside of the slide 24 when the latter is moved downwardly.

It should be understood that one or more anerators may tend each of the die-carriers, the number assigned to each carrier being governed chiefly by thenature and number of blanks to be pressed by the die on that carrier in each pressing operation. The radial arrangement of the die-carriers affords areas therebetween wherein the operators and tables for blanks may be positioned.

The die-carriers 35 are all alike and function alike. Each has a flat top 36 having suitable provisions (not shown) for mounting a die thereon. The top 36 is preferably substantially rectan ular in shape, as best seen in Fig. 2, and the die or dies I sometimes referred to hereinafter as a "die assembly) used on a carrier would be arranged within the rectangular area of the die-carrier top. The die-carrier 35 is preferably movable longitudinally upon a plurality of wheels 31 suitably mounted on opposite sides of the die-carrier, as best seen in Figs. 6, '7, 8 and 9, through the medium of ball bearings 38 disposed upon stub bolts act with that die-carrier. For example, referring to Fig. 2, the wheels 31a, 31b, 31c, 31d, 311a and 31f will, when their related die-carrier is in operative position in the press, rest, respectively. upon plugs 44a, 44b, 44c, 44d, 44c and 44); and, when any other die-carrier is moved into operative position, a similar combination, including different plugs, will .coact with the wheels 31 on such other carrier and support the latter.

One form of yieldable plug which may be employed for this purpose is illustrated in detail in v Fig. 5. In this particular structure a bore 45, of suitable depth, isprovided inthe bed 32,-and

' within the said bore may be disposed one or more 39 which may be.screwed into or otherwise held within lugs 40 formed on the underside of the die-carrier. In the embodiment illustrated, six wheels are provided on each die-carrier, three on each side, and these wheels roll upon a horizontal portion 4| of angular tracks 42. Vertical side .rails 43 of said tracks extend upwardly beyond the wheels 31, where they serve as guides which may coact with adjacent sides of the die-carrier to assure proper linear movement of the latter.

The bottom of each die-carrier is substantially flat and, as best seen in Figs. 7 and 8, is in a horizontal plane slightly above the bottoms of the wheels 31. tire bottom of the die-carrier may rest upon and be supported by the bed 32 during a pressing operation, yi eldable 'plugs 44 are provided at suitable points in the bed of the press. These plugs are so disposed that when any one of the die-carriers 35 is moved into operative position upon the bed of the press, all the wheels of said die-carrier will rest upon certain of the plugs 44 arranged to c0- In order that substantially the en'- helical compression springs 46 of such characteristics that a carrier 35 with die and blanks disposed thereon may be supported without yielding.

The springs 46 rest upon the bottom of the bore and press upwardly upon a cap 41 having a dependiing, vertical, annular flange 48 terminating at its lower end in a horizontal annular flange '49 which may be engaged by a shoulder 50 of a suitable keeper 5|, in the form of an annular ring, which may be screwed into the bore 45 or otherwise retained therewithin in any suitable manner. It will be seen that by means of this arrangement the wheels 31 of the'die-carriers are free to roll upon the plugs 44, but, when pressure is applied to the die on said :carrier during a pressing operation, the plugs 44 will yield and permit the flat bottom of the die-carrier to rest upon and be amply supported by the bed '32 of the press. Y t

Each of the die-carriers is provided with similar means for moving it into and out of the press between operative and inoperative positions. These means may be best understood by reference to Figs. 6, 7 and 8, from which it will be seen that each die-carrier is provided on the underside thereof with a longitudinally extending rack 52 suitably fixed to the carrier by machine bolts 53. The rack52 is driven through the medium of a pinion 54 which is turned, through suitable reduction gearing, by a reversible electric motor 55, mounted upon a support 56 suitably secured to a lug 51 on one of the legs 34 by one or more bolt 58, and to a projection 59 on the base 2| of the press by a bolt 60 which passes through a suitable hole in a lug 6! on the support 56 and is screwed into said projection; all as best seen in Fig. 6.

a The motor 55 may, if desired in actual practice, be adapted to operate at several speedsfin each direction, but, as such arrangement forms no essential part of the present invention, the motor as described may be considered as a single-speed, reversible motor.

Means are preferably. provided, independently of the characteristics'of the motor, whereby the die-carrier "may start and stopat relatively low speed and may be caused to step at a precise de-, sired point. The results, just referred to, may be accomplished by the use of a mechanical movement'which is immediately hereinafter described. Members 62 and 63, shaped somewhat like beaver tails, and hereinafter referred to by that name, are fixed at the inner and outer ends, re-

spectively, of the rack 52; the beaver tail 62 being "adapted to control the starting and stopping, re-

spectively, of the die-carrierin its movement from and to its outermost or inoperative position; while the beavertail 63 is adapted to control the stopping and starting, respectively, of the die-carrier in its movement into and from its innermost or operative position.

As shown in Fig. 6, the die-carrier 35 is in its outermost position, and a pair of rollers 64, carried at the outer ends of an arm 65 suitably arranged to rotate with the pinion 54, are in rolling engagement with opposite outer points of the beaver tail 62 in a horizontal line substantially coincident with the center of said pinion. The

- teeth'fla of the rack 52 are cut away, as best seen at 52b, at the portionthereof which is overlaid by or coincident with the beaver tail 62, so that, when the-motor as is started to initiate the movement of the die-carrier 35 toward the left, the pinion 54 and, with the latter, the arm pinion 54, and the right side of the beaver tail 62.

The beaver tailis so shaped above and below its central horizontal diameter, coinciding with the center of the pinion 54, that the said coaction between the rollers 64 and the side edges of the beaver taili2 causes the die-carrier to move relatively slowly at first and to increase its speed somewhat as the rack 52 moves to a point beyond where the teeth 52a are cut away andwhere the said teeth then enga e the pinion 54. The progressive increase in speed of the die-carrier, resulting from the said coaction ofthe rollers 64 and the beaver tail 62, preferably is such that the die-carrier speed, at the moment the said coaction ceases, is substantially the same a the speed at which it will be driven as a result of the direct coaction between the teeth of the pinion I4 and the teeth of the rack 52.

As the die-carrier approaches its innermost position and reaches a point where the teeth of the rack 52, coincident with the beaver tall 63, are cut away, the rollers 64, as they rotate with the arm 65, engage the beaver tall 63 and slow down and stop the die-carrier by a coaction which functions oppositely to that Just described with respect to the starting movement of the diecarrier.. As the rollers 64 first enter into coaction with the beaver tall 83, one of said rollers engages the beaver tail substantially at its lower-v most point and, in its counter-clockwise movement, mils upwardly to the right along the lower right side of the beaver tail, the other roller 84 meanwhile coacting with an upper portion of the left side of said beaver tail until the die-carrier It comes to rest, at which time the arm 45 is in a substantially horizontal position.

It should be observed that the beaver tails 6,2 and 63 function similarly and that their coaction with the rollers 64 is reversed when the movement of the die-carrier is reversed to bring the latter again to its outermost position. It should also be understood, and it will hereinafter be explained in greater detail, that suitable means are provided for breaking the electric circuit to the motor 5! at the proper time in order to cause the diecarrier 35 to stop at the desired point.

The beaver tail arrangement is useful not only for imparting relatively slow movement to the die-carrier in starting and stoppin but also for assuring that the die-carrier will stop at the precise point desired both in its innermost and its outermost positions. The latter desirable result flows from the fact that, during a limited portion of the rotation of the arm 65 when thelatter is in or nearly in a horizontal position'upon the starting and stopping of the motor, the rollers 64 coact with opposite surfaces of material circumferential length, on the beaver tail, which surfaces are substantially concentric with respect to a point on the beaver tail which coincides with the axis of the pinion '54. During movement of the rollers 64 over such opposite concentric surfaces on the beaver tail, there can be no resulting movement of the die-carrier; hence, to assure stopping of the latter at a precise desired point, it is onl necessary to so arrange the circuit cutoif of the motor 55 that the coasting of the latter causes the rollers 64 to move into engagement with said concentric siu'faces and to stop while in such engagement. Such a motor cutoff arrangement, of course, may be easily provided.

In order that the beaver tails 62 and 63' may be in positions wherein they may coact with the rollers 64 when the die-carrier is at the precise operative and inoperative positions desired, the said beaver tails are mounted on extensions 66 and 61 at each end of the die-carrier 35, as best seen in Fig. 2. Also, as may be observed from Figs. 6, 'l and 8, the beaver tails extend substantially below the bottom of the die-carrier. This disposition of the beaver tails enables them to be used not only in controlling the starting and stopping of the die-carriers in the manner already explained, but also in guiding a die-carrier as it My" moves to and from its operative position upon position posed die-carriers are in a common line extending through the center of said b'ed, it will be seen that each slot may receive and coact with the beaver tails on either of two opposite die-carriers. The vertical side rails 43 on the die-carrier runways may, of course, only coact with the diecarrier as guides for the latter while the diecarrier is substantially over said runways. The beaver tails perform an important function in guiding the die-carriers at a time when the diecarriers are substantially clear of the vertical side rails 43 of said runways.

A further advantage is'derived from using the describedbeaver tail construction on the diecarriers, inasmuch as the cutaway portion of the teeth 62a, at 5211 aflords ample clearance between the top of the pinion 54 and the adjacent surface of the rack 42 to accommodate the vertical movement of said rack which occurs when the die-carrier is pushed downwardly somewhat upon the yieldabie plugs 44 at the time the press c oses.

In the embodiment illustrated in the drawings, a resilient pressing member is mounted on the underside of the slide 24 and is adapted to coact, in the pressing operation, with a die or dies mounted on any one of the several die-carriers which may be moved into operative position upon the bed of the press. In order that such a pressing member may coact properly with any one of said dies, the mounting of said pressing member is such that it may be rotated about a vertical axis passing through the center of the bed 32.

Such a pressing-member, in the form of a resilient pad '69 (Figs. 3 and 4) which may be formed of relatively soft rubber or other suitable resilient material, is preferably mounted within dimensions of the saidpad-holder are preferably.

slightly greater than the corresponding dimen-. sions of the die-carrierand die to be used in the press, so that during the pressing operation the die-carrier may extend partly into the padholder and compress the material being processed between the die and the pad. The pad-holder Ill may be provided with mounting flanges ii,- and with strengthening webs I2, and may be secured in any suitable manner, as, for example, by bolts i3 in a central position upon the underside of a rotatable, horizontally disposed dial I4.

A spindle I5 formed integrally with the dial It, or otherwise fixedly secured thereto, extends upwardly from the center of said dial through a bushing I6 fixed within a bore 11 in the slide 24 and into a suitably dimensioned recess I8 in the lower end of the ram 26. A ball bearing assembly I9 is arranged to receive the thrust of a thrust plate 80 which is suitably secured upon the upper end of the spindle I5, as by a screw 8|. By this arrangement the dial is effectively supported and may turn freely upon the ball bearing assembly i8.

The dial 14 may be rotated in either direction by a reversible electric motor 82 fixed upon the side of the main slide 24. The said motor drives a pinion 83, preferably through reduction gearing (not shown), which may be carried within the motor casing, and the said pinion may mesh I with teeth formed in the periphery of the dial I4 or with similar teeth of a ring gear which may be fixed in any suitable mannerupon the periphery of said dial.

As best seen in Fig. 3, a plurality of beaver tails 85 are bolted to and extend outwardly from the dial I4 at desired points thereabout to coact with rollers 86, arranged to turn with the pinion 83 similarly to the coaction of the roller and beaver tail arrangement provided on the diecarriers 35. Thebeaver tails 85 function similarly to the beaver tails 62 and 63 to control somewhat the speed of the dial in starting and stopping, and to assure stopping of the dial at a precise point desired. It is to be observed that the several beaver tails .85 are so positioned that one of them may coact with the rollers 86 at any one of the six stopping points of the dial.

The press is equipped with various electric switches which control the operation of the moving parts of the press'andwith suitable dogs for actuating various electric switches, As is well known to those skilled in the desi construction and operation of presses, such dogs and the switches with which they coact may be mounted optionally in various positions, and, as the functloning of said dogs and switches relates primarily to the electric control system of the press,

they have not been shown in any of the figures hereinbefore described in detail but are shown diagrammatically in Figs. 11a, 11b, 11c and 11d,

which illustrate the said electric control system.

tact switches control various relays which,.in turn, control motors actuating certain moving parts of the press and electric solenoids which, through a suitable valve arrangement, control the closing and opening of the press.

In the said electric diagram, straight lines are employed to indicate wiring connections between the various pieces of apparatus. The said lines necessarily cross in many places but such crossing should be taken as representing connections of wires only where clearly indicated by the use of solid black circular spots at such crossing points.

Referring generally to the several said relays, the latter, structurally, each comprise 'an electromagnet and various contactors constituting switches which are opened or closed when said magnet is energized and de-ehergized. Fig. 10a shows symbolically such a relay comprising a magnet 2H and five contactors Zllb, 2I'Ic, ZI'Id, 2 He and Zllf, in positions underneath said magnet from which (assuming said contactors to be linked together to move in unison) they may be moved upwardly toward the said magnet, when the latter is energized, so that contactors 2H?) and 2I'Ie move from contacting or closed positions to non-contacting or open positions while contactors 2H0, 2nd and 2H move from open to closed positions. Hereinafter the several contactors in the several relays willbe'referred to as switches, and said switches may be referred to as normally open or normally closed, depending upon their positions when their actuating magnet is in de-energized condition.

The use, in. the electric diagram, of a symbolic representation such as is illustrated in Fig. 10a, would immeasurably complicate said diagram, and, therefore, symbols as shown in Fig, 10b are employed in said diagram in place of symbols as shown in Fig, 10a. In the electric diagram a relay magnet ,and its associated contactors or switches are not shown in their actual structural relationship, but such relationship is 2.01 curately and clearly indicated in said diagram by applying to the several contactors or switches a reference character formed by adding a distinguishing letter, taken from the first part of the alphabet, to the number used as a reference character for the magnet which actuates such contactors or switches, irrespective of where said switches may be located in said diagram. Thus, Fig. 101) symbolizes magnet'fll in de-energized condition with switches 2112) and 2|Iein normally closed positions and switches ZI'Ic, 2nd

' and 2H in normally open positions. Throughout the drawings all relays are represented by the symbols shown in Fig. 10b, and the magnetically controlledswitches which are normally closed may be distinguished by the diagonal line extending through the representation of contact points, while the absence of such a diagonal line 'the several magnets and the switches controlled thereby are ordinarily mounted in practice upon a suitable panel usually disposed near the press.

In Fig. 11a, in order to simplify the electric diagram, onlythree of the six movable 'dieconsidered asviewed from above,

carriers are diagrammatically illustrated, such structure being shown in broken lines in order to cause the electric apparatus and wiring to stand out clearly. It should be understood that the three omitted die-carriers have similar associated electric apparatus and are operated and controlled similarly to those shown.

The several die-carriers 35 are distinguished from each other in Fig. 11a as A, B and C, and In Fig. 110 the same letters are employed within circles to indicate corresponding positions of the rotatable dial. In the latter figure positions D, E and F of said dial are similarly indicated, corresponding to the positions of the three die-carriers omitted from the diagram. In the various diagrams in Figs. 11a and 110 the several diecarrlers 35 and the rotatable dial 14 are to be Referring to Fig. 11a the die-carrier A has a dog AI mounted thereon on one side thereof and two dogs A2 and A3 on the other side. All these dogs may be mounted toward the outer end of said carrier by any suitable means, such as, for example, by a rigid extension I06. Adjacent to one side of the die-carrier and in positions wherein they may be actuated bythe dog AI are arranged dog-actuated switches Al I and AI 2, which are preferably fixedly mounted by any suitable means upon some non-movable portion of the press structure, the former switch being disposed toward the outer end of the die-carrier support and the latter switch toward the inner end of said support. Somewhat similarly arranged adjacent to the opposite side of the diecarrier, in positions wherein they may be actuated by the dogs A2 and A3, are dog-actuated switches A2l, A22, A32 and A42, which also are preferably fixedly mounted by any suitable means upon non-movable portions of the press structure. Switch A2I is disposed toward the outer end of the die-carrier support, and switches A22, A32 and A42 are disposed toward the inner end of said support. i

The several dog-actuated switches referred to in this specification may preferably be swingarmtype switches which operate when said arm is-engaged and swung angularly by a coacting dog. The normal" conditions of such switches (the conditions thereof when not engaged by any coacting dog) are indicated by legends on the electric diagram.

The dogs A2 and A3 are preferably so disposed.

that they move in different paths with the movement of the die-carrier. In the present disclosure it should be considered that they are disposed at different levels and that dog A3 protrudes sidewisely with respect tothe die-carrier, somewhat more than dog A2. It also should be understood that, in the present disclosure, switches A32 and A42 are disposed with their swing-arms in the path of dog A2, and, hence, are operated by said dog A2, and that switches A2I and A22 are disposed with their swing-arms in the path of dog A3 and, hence, are operated by said dog A3. The switch-engaging surfaces of dogs Al and A3 may be quite long, as indicated in the drawings, but dog A2 should preferably have only a relatively short surface, as illustrated, adapted to operate its associated switches, this being desirable because switch A32 should only be momentarily operated and switch A42 should be held closed only when the die-carrier is in the precise "in position in which it will coact properly with the pad 69 in a pressing operation, all as hereinafter more fully explained.

'lected die carried on any die-holder.

and A3, respectively, hold switches A42 and A22" closed. It will also .be helpful to observe that, as the die-carrierapproaches "in" position, dog A2 engages and momentarily closes switch A32. Said dog, however, passes beyond and disengages switch A32, permitting it to open, before the diecarrier comes to rest at its innermost position.

It should be understood that all die-carriers on the press are provided with coacting dogs and switches which are similar to and function as those described in this paragraph. They have been given reference characters comprising the same numerals as those here referred to, prefixed, however, by the letters used to identify the related die-carriers, thus, dogs BI, CI, etc., and switches BII, CII, etc.

Referring to the larger showing of the rotatable dial 14 toward the left of Fig. 11c, four similar dogs to, 0:. y, z are suitably formed or otherwise carried, in a common horizontal plane, about the periphery of and on said dial. The said dogs are disposed apart and are adapted to coact with and operate switches AL and AR, BL and BR, CL and CR, DL and DR, EL and ER, and FL and FR,.in a ma er hereinafter explained, whereby to control t e rotation of said dial so that the said dial and the pad-holder 10, carried thereby, may turn, if necessary, either to the right or left, as indicated by the directional arrow, to cause the pad-holder to mate with a se- The lastmentioned switches are fixedly mounted, by any suitable means, upon the slide 24 of the press, in such positions that they may coact with and be operated by the several dogs 10, :c, 11 and 2.

Also, in Fig. 110, two other horizontal planes are presented with reference to the dial 14. In the upper one of these presentations are shown six similar dogs I 01, suitably formed or otherwise carried in a common horizontal plane different from the plane of the dogs w, x, 1/ and 2, about the periphery of and on the dial 14. The dogs I" are disposed 60 apart and are adapted to coactwith and operate switch SL, in a manner hereinafter explained, whereby to stop left movement of the dial 14 as indicated by the directional arrow thereon. In the lower one of these presentations are shown six similar dogs I08, suitably formed or otherwise carried, in a common horizontal plane different from the planes of the dogs w, :c, 1/ and z and dogs I01, about the periphery of and on the dial 14. The dogs I00 are disposed 60 apart and are adapted to coact with and operate switch SR, in a manner hereinafter explained, whereby to stop right movement of the dial I4 as indicated by the directional arrow thereon. The switches SL and SR are fixedly mounted, by any suitable means, upon the slide 24 of the press, in such positions that they may coact with and be operated by the dogs I01 and I08 respectively. Also, in the lower the dogs |08 when the dial M is at rest in any one of the six positions in which the pad-hojder 10 may function in a praising operation. Said switch DS is adapted to function, in a manner hereinafter explained, to assure that the press may not close except when the dial I4 is in a proper pressing position.

It should be observed that the several dogs are not disposed directly over the dogs I08. Taking as a stopping point, the common circumferential point indicated on the two small diagrammatic presentations of the dial I4 by the arrows I09, it will be apparent that, whenever the dial stops rotating, the dog I0|- nearest said point will be somewhat to the left thereof, while the nearest dog I08 will be somewhat to the right thereof. The circumferential disposition of the so circumferentially disposed as to function similarly to dogs I01 to stop right rotation of the dial. Each of switches SL and SR should be of the type which operate when the swing-arm thereof is swung in one direction but not in the other direction, and be so disposed that on left rotation the switch SR is inoperative even though tripped, and on right rotation switch SL is similarly v inoperative.

Although the dogs 10, x, y, 2, I01 and I08 have been described herein as disposed in different horizontal planes, it will be understood that other arrangements thereof may be employed to yield the desired operation of the press.

Switches SU and SD, which, as hereinafter explained, respectively function to stop up and down movement of the press slide 24, are suitably fixed, the former upon the crown 22 of the press and the latter upon the base 2| of the press. The said switches, respectively, are operated by dogs H0 and III fixed pon a rod 2 which is suitably connected, as y an arm 3, to the slide 24, and adapted to move verticallywith said slide within guides I I4 and H5 suitably connected to the crown 22 and the base 2| of the press.

The relation of the electric apparatus to the press, whereby opening and closing of the latter be discharged from said valve through pipeline 93 into hydraulic chambers 92 to open the press, the fluid from chamber 89 meanwhile being exhausted through pipe line 90 into the distributing valve 9| and thence through pipe line as into' the fluid reservoir 95. When the plunger 99 is moved downwardly to a lowermost position, the pistons 99a, 99b and 990 will cause fluid, pumped into the valve through pipe 91, to be discharged from said valve through pipe line 90 into hydraulic chamber 89, causing the press to close, the chambers 92 meanwhile being exhausted through pipe 93 into.the distributing valve 9|, and thence through pipe line 98 into the fluid reservoir.

The movement of the plunger 99 to the several positions just referred to may be controlled by electric solenoids I00 and medium of a lever I02 which is pivoted at an intermediate point upon a bracket I03 suitably fastened to the casing of the distributing valve. The opposite ends of the lever I02 are connected to the two solenoids by links I04 and to an upperend extension of the plunger 99 by a link I05. When solenoid '|0I is energized, the right end of he lever |02 is drawn downwardly and the lunger 99 is moved to its uppermost position, thereby causing the press to open in the manner already explained. On the other hand, if solenoid I00 is energized, the right end of the lever I02 is drawn upwardly, thus moving plunger 99 to its lowermost position, thereby causing the press to close.

is accomplished, is shown in Fig. 11d. As illustrated therein, a hydraulic chamber 89, adapted to effect the closing stroke of the press, is suitably connected by a pipe line 90 to one chamber in a distributing valve 9|, and hydraulic chambers 92, adapted to effect the opening of the press, are connected by a pipe line 93 to another chamber in said valve. A fluid pump 94, which may be driven by an electric motor (not shown), draws fluid from a fluid reservoir 95 through a pipe line 96 and pumps it through a pipeline When neither of said solenoids is energized, the plunger 99 is moved to and held in an intermediate position by a spring (not shown) located at the lower end of said plunger within the" casing of the valve 9|, in which position the pistons 99a, 99b and 99care so disposed withinsald valve that fluid cannot move through either pipe line 90 or line 93. Thus, when neither solenoid is energized, the press slide 24 is held immovable. In order to handle the fluid discharged from the pump 94 while the plunger 99 is in said intermediate position, interconnected longitudinal duct 99d in said plunger and lateral ducts 99c in the pistons 99a, 99b and 990 are provided to pass fluid, from pipe 91, through the interior of said plunger and pistons, into pipe 98 and thence into reservoir 95. The two solenoids justreferred to are electrically controlled, in a mannerto be hereinafter explained, to automatically open and close the press.

Considering now Figs. 11a to 11d, inclusive, together, main power wires 30| and 302 are connected in parallel to a suitable source of electric energy. Each circuit includes only one relay magnet. The magnets have been given reference numbers in a 200 series, su'ch,'for example, as 20I, 2 I 9, etc., and all the wires which function only in one circuit are given reference numbers of the magnet in that circuit with a letter suffix from the latter part of the alphabet; thus, the wires 91 to a third chamber in the distributing valve,

while a fourth and a fifth chamber in said valve are connected by a pipe line 90 to the said reservoir.

The several chambers of the distributing valve and the inner construction thereof are substantially as shown in the drawing. The operation of said valve is such that when plunger 99 of said valve is in its'uppermost position, as shown in the diagram, the several pistons 99a, 99b and 990, formed integrally with said plunger, will cause fluid, pumped into the valve through pipe 91, to

3040, 304d, 3046 and 30 (Fig. 11a).

in circuit with magnet 20| have been numbered 20Il, 20Im, etc. the wires in circuit with magnet 2|9 have been numbered 2I9Z, 2|9m, etc. Other wires, common to several circuits, have been given reference numbers in a 300 series.

The wire 30| is connected to a main take-off wire 303 through a series of six, manually op,- erable, normally closed safety switches 304a, 304b, One of said safety switches is provided for and mounted conveniently near to each die-carrier, so that at any time, as in an emergency, an operator of any one switches, and selector push-button switches 30!,

301, etc., hereinafter referred to, are the only parts of the disclosed electric apparatus which the operators of the press must manipulate. .Most of the circuits are considered as proceeding from main take-oi! wir 303 or from other so-called take-oi! wires, hereinafter mentioned, to wire 302, and, as far as possible, the. various circuits have been arranged to begin and end at said wires at substantially similarlevels on the diagram.

A cycle of operation may be considered as starting with all the apparatus in the positions shown in Figs. 11a, 11b, 11c and lld, except that both solenoids I and Ni should be considered as deenergized and plunger 90 of valve 9| in its intermediate position, holding the press slide 24 in the up position indicated.

Assume that operator B (each operator being herein identified by reference to the letter characterizing the die-carrier which he operates) has finished loading his die with blanks and desires to move it into the press in order toperform the pressing operation on said blanks. He presses selector button switch 306, thereby momentarily closing a pre-selection circuit from main take-oi! wire 303 to wire 302 through then-closed switch 23'"), pre-selection take-off wire 3||,-wires 3" and .2021, magnet 202, wire 202m, switch B2| (then held closed by dog B2) and wires 2021i and 3. This closed pre-selection circuit energizes magnet 202, which thereupon simultaneouslyoperates all switches controlled thereby, i. e., it closes switches 202a, 202b, 202a (Fig. 11b), and 202d (Fig. 110), all of which-are normally open.

Switch 202a, upon being closed by magnet 202 at the beginning of the cycle, holds said pre-selection circuit closed even after button switch 300 is released by operator B by maintaining a con-, nection direct from main take-off wire 303 through wire 202p to wire 2021., Thus, the-said pre-selection circuit is maintained until switch DH is opened by disengaging dog B2 as carrier B moves inwardly in a manner hereinafter explained.

Switch 202b, upon being closed by magnet 202 at the beginning of the cycle, closes a circuit from main take-oi! wire 303 to wire 302, through wire 2.1m magnet and wire The function move into the press, such pre-selection may not of the latter circuit is to open switch 201p, the only switch operated by the magnet 2", thereby preventing the establishment of a pre-selection circuit for any of the other die-carriers until the I die-carrier first selected (carrier B in the present example), on moving inwardly, has opened switch B2|, thus de-energizing magnet 202, whereby switch 202!) is opened and magnet 201 de-energlued. This permits switch 20'lb to close again 80 that, at any time after one die-carrier has started to move inwardly, the operator of any other diecarrier may press the button switch controlling 1 his carrier to assure that it will be to enter the press.

Switch 202d (Fig. .magnet 202 at the beginning of the cycle, coacts with switch BL to assure that dial I3 and padholder on said dial will turn .60 to the left so that said pad-holder will move from the position the next one thereof indicated in solid lines (its disposition 7 at the beginning of the eycle) to the vertically indi ted position in whiohsaid pad;holder will tewith die on carrier .3 after the latter has moved into the press.

The further operation of 1m, upon beingclosed by fully explained hereinafter, following said diecarrier description.

Switch 202e, upon being closed by magnet 202 at the beginning of the cycle, closes a selectionmaintaining circuit from main take-off wire 303 to wire 302, through switch 2 lie, selection-maintaining take-oil wire 3|5, wires 3|! and 2|2l, magnet 2|2, wire 2|2n, switch 2||c, 'wire*3|l, switch 30, wire 320, switch 2|3b, wire 32l, and thence through switches 22|b and 2|0c, all the switches irrsaid circuit thenbeing in closed position in response to the then existing conditions of their respective controlling magnets. The circuit through magnet 2|2, just described,-energizes the. latter and,-hence, at the beginning of a cycle, operates switches 2|2a, 2| 2b, 2|2c and 2 I242,

Switch 2l2a, upon being operatedby magne 2| 2 when the latter is energized at the beginning of the cycle, closes to hold the circuit through 5 magnet 212 closed by maintaining a connection the dial 14 will be direct from main take-oil. wire 303 through wire 2 |2m to wire 2 I21. Thus, the said circuit is maintained through magnet 2 I 2, and, consequently, the selection of die-carrier B, as the next one to go into the press, is maintained until the arrival of the said die-carrier at in position, when switch 2|0b is opened by the energizing of magnet 2", which takes place when switch B32 is tripped closed by dog B2.

Switches H20 and 2|2d, upon being operated by magnet 2|2, when the latter is energized at the beginning of the cycle, open whereby to assure that, while the circuit through magnet H2 is functioning, the circuits through magnets 2| and H3, in which circuits said switches are located, will not function, thus assuring that no selection may then be maintained through the a medium of magnets 2H and 2|: for die-carriers 203, etc., immediately after one die-carrier (carrier B in the present explanation) has started to be carried into any of the selection-maintaining magnets 2||. 2l2, 2|3, etc., while die-carrier B (or any other carrier) is in other than its out position, for, during all 'of the latter period, switch 2|Ie is held open by magnet 2| I, which is energised during said period because switch B is closed while carrier B is in other than "on position. Thus double assurance is provided that only one die-carrier selection may become effective at one time.

Switch 2I2b, upon being operated by magnet 2 l2 whenthe latter is energized at the beginning and "out windings thereof. The said connec tion may continue'through the "in" winding of said motor. and thence by wire 323, switch 23|d and wire 324 to wire 302, whereby to cause said motor to operate andv move die-carrier B in- ,wardly. To cause outward movement of the said die-carrier, a similar connection may continue from said common terminal, through the "out winding oi" said motor. and thence by wire 325,

switch 232d and wire 328 to wire 302. The man.- ner in which switches 23id and 232d are closed to cause "in" and out" bperation, respectively, of the motor 65 of'die-carrier B will be hereinafter explained.

It should be understood that while the closing of switch 2i2b by magnet 2i2 establishes conand, in consequence, opening switch 2i'ib. This. considered alone, would, of course, open the above-described circuit through magnet 23i. but,

nection to the said common terminal of the motor of carrier B. the corresponding switches 2] lb and 2l3b, which are similarly related to carriers A and C, respectively, and similar switches (not shown), related to the three omitted carriers, all remain open, thus assuring that only the motor of carrier B will operate. Also, having a circuit partially established through the motor of carrier I B, it is evident that said motor circuit will be completed through the "in" winding thereof to cause carrier B to move inwardly ii switch 23id is closed, and will be completed through the "out" winding thereof to cause said carrier to move outwardly if switch 232d is closed. Various dogactuated switches operated by dogs carried by the carrier (carrier B in the cycle being described) control the circuits through magnets 2i! and 220, to operate switches which iunction to control the circuit through in" magnet 23l and "out" magnet 232. and, hence, to control the said switches 23ld and 232d operated, respectively, by the two'latter magnets. whereby the carrier may move in when it is out and may move out when it is in.

As it is desired to cause die-carrier B to move from its out" position into the press, the inter; relationship and coaction of magnets 2", 220. 23i and 232 and the switches operated thereby may best be considered by first observing the condition of such electric apparatus when all diecarriers are out."

When the said carriers are all out," magnet 220 is energized by reason of the fact that switches Ai2, Bi2, Cl2, and 2l9b, which are arranged in series and control the circuit through said magnet, are all in closed position, and magnet 2l1 is de-energized by reason of the fact that the switches All. Bil and CH. which are all connected in parallel relatively to each other and are collectively connected in series in the circuit through magnet 2li, are all held open by the dogs Ai, Bi and Cl.

Following the effect of the conditions stated in the preceding paragraph. into the circuit of magnet 23i, it will be seen that. when all die-carriers are out." said magnet is in a closed circuit between main take-off wire 303 and wire 302 which includes switch 2i'ib, then in its normally closed position because of magnet 2i! being de-energized, switch 232b. then in its normally closed position because of magnet 232 being do-energized as hereinafter explained, and wires 23il and 321. Hence, in" magnet 23l is energized and, in conseouonce, switch 23M is closed, completing a circuit through the in" winding oi the motor of die-carrier B. causing the latter to move inwardly. as is desired. -Meanwhiie, magnets 220 and 23i being energized as aforesaid, switches 22% and 23) are held open. ihlls krvping out" magnet 232 (lo-energized and keeping switch 232d open, thereby preventing the establishment of a closes switch Bil, thereby energizing magnet 2i1 as it is essential to keep the latter magnetized in order to hold switch 23id cl'osed,'whereby to maintain the circuit through the carrier motor until the carrier reaches in" position, a maintaining circuit was established around said switch 2l'ib while the carrier was-out. said circuit including switches 2200 and 23 la, the former switch being held closed because of magnet 220 being energized at all times except when a carrier is "in," and the latter switch being held closed as long as magnet 23i itself is otherwise maintained in energized condition. a

Also, as carrier B starts to move inwardly, the energizing of magnet 2", resulting from the closing of switch Bil, causes switch 2lle to Open, thus preventing any further selection circuits from being established and maintained. either through magnets 2li, 2i2 and 2l3, controlling the maintenance of die-carrier selection, or through the several dog-actuated switches controlling the direction of movement of the rotatable dial it. until the selection circuits already I established therethrough have fully performed their functions and have been broken.

Also, as carrier B starts to move inwardly, dog B3 disengages and opens switch B2|,"thereby deenergiz'ing magnet 202. In consequence, switches 202a, 202b, 2020 and 202d open, magnet 20'! is de-energized. and switch 20') closes, whereby to restore the several pre-selection circuits to a condition wherein they may function in the manner already explained when another diecarrier is loaded and ready to be moved into the press. As will be hereinafter explained, such further selection may be established as soon as one die-carrier (carrier B in the present cycle) has started to move into the press.

Having pursued the operation of the various electric circuits and apparatus to, the stage in the cycle wherein the carrier B, in moving inwardly, has caused dogs Bi and B3 to disengage switches Bil and B2i, it is apparent that the carrier B will continue to move inwardly and that there will be no further changes in the various die-carrier circuits until said carrier has moved inwardly sufiiciently to cause said dogs and dog B2 to engage and operate switches BI2, B22, B32 and B42. The effect of such operation of said switches, as bearing upon the operation of the die-carriers, will now be explained.

Upon carrier B reaching in" position, dog Bl engages and opens switch BI2,' de-energizing magnet 220,,thereby opening switch 2200 and thus breaking the maintaining circuit through "in" magnet 23i, de-energizing the latter. This causes switch 23id to open, thus breaking the circuit through the "in" winding oi the motor of carrier B, whereby to stop the "in" movement of the latter. Upon magnets 220 and 23l becoming de-ener'gized, as just explained, switches 22% and 23ib close, thereby energizing "out magnet 232 and, in consequence, closing switch 23211 which is connected by wires 325 and 326 between wire 302 and the "out winding of the motor of carrier B. -The said motor, however, will not then operate to cause carrier B to move out immediately, for switch 2i2b, which also controls the circuit of said motor, has been opened in the manner hereinafter described. and will not close again to complete the circuit through said motor and move-the die-carrier out until after the pressing operation has been completed and the press opened.

Similarly to the maintaining circuit which held "in magnet 23| energized while carrier B moved to its "in position, a maintaining circuit is established around switch 2201) to hold out magnet. 232 energized until carrier B, later, reaches its out position. The latter circuit includes switches 2 He and 232a, the former switch being held closed because of magnet 2 being energized when any carrier is in other than an out position, as already explained, and the latter switch being held closed as long as magnet 232 itself is otherwise maintained in energized condition.

Upon carrier B reaching in position, dog B3 engages and closes switch B22 and as the latter is in series with then-closed switches H31) and CI2, said switches form a connection between main take-off wire 303 and the side of magnet 2l2 which is remote from wire 302. The circuit through magnet 212, however, cannot be reestablished at that time, nor thereafter, to close switch 2l2b in order to start carrier B moving outwardly, until the press has closed and opened again. This is due to the fact that switch 22|b -is opened immediately upon carrier B reaching "in" position and held open during the closing stroke of the press slide 24, and also because switch 2l0b, in the circuit of said magnet 2|2, is opened upon carrier B reaching "in position and cannot close again until the slide 24 has completed its subsequent opening stroke, all as hereinafter more fully explained.

Upon carrier B approaching "in position, dog

B2 engages and momentarily closes switch B32, completing a circuit between main take-of! wire 303 and wire 302, including wires 2l8l and 2l8r, switch'B32, wires 2|8s and 2l8v, magnet 218 and then-closed switches HM and 224d. Upon magnet 2! becoming energized through this circuit,

switch 2| 8b opens, thus tie-energizing magnet 2l2 and opening switches 2l2a and 2l2b, the latter of which controls the motor of carrier B. Thus, said motor is stopped and cannot operate again until a circuit is again established through the out winding thereof upon the completion of a pressing operation. Although, as just stated,

switch B32 is closed only momentarily. that. momentary closing and the consequent energizing of magnet 2I8 causes switch 2l8a to close and the latter switch replaces switch B32 in holding magnet 2l8 energized even after dog B2, in completing its "in" movement, has passed beyond and disengaged and opened switch B32. i

' After dog B2, in the latter part of its in movement, disengages switch B32, it engages and closes switch B42, which is connected in series with magnet 22! by wires 328, 329, 330 and 33I. Dog B2, as:- may be observed, has a very small switch-engaging surface, and, hence, switch B42 may not be held closed by said dog unless the die- .carrier is in the precise in" position in which dies carried thereby may properly cooperate with the pad 69 and the pad-holder l0. 'I'he disposition of the dog B2 and of the switch B42 should be such that said switch will not be held closed by said dog unless the die-carrier B comes to rest in that position upon the bed of the press in which such proper cooperation may occur. Under this arrangement, the switch B42 will be 0 held closed and magnet 22l may be energized to close the press, in the manner hereinafter de-.

scribed, only if the die-carrier is in the proper position on the bed of the press.

to move downwardly to perform a pressing operation, and immediately upon said slide reaching a point where such pressing operation is complete, said slide automatically returns to its uppermost or open position and thereautomatically stops, whereupon the die-carrier that has been in the press is automatically caused to move from an operative position within the press to an inoperative position alongside the press. This automatic operation is largely controlled through magnets 218, 2|9, 22l, 223 and 224 and solenoids I00 and IN, most of which are shown in the diagram in Fig. 11d. As the circuits in the latter figure are so clearly defined in the drawings, it appears unnecessary to refer to the various wires in said circuits by any particular reference characters.

The solenoid I00 is adapted to operate valve 3| in order to cause downward or closing movement of the press, and the circuit through said solenoid is completed through switches 22 Id and 22in, both of which are operated by magnet 22l. Solenoid I01 operates said valve inorder to efiect upward or opening movement of the press, and its circuit is controlled by switches 22311 and 223e, both of which are operated by magnet 223.

It should be helpful, at this point, to observe that magnet 2 l0 and the switches which it operates perform important functions not only in stopping the in movement of the die-carrier in the manner already explained, but, also in initiating the closing of the press and in initiating the out movement of the die-carrier upon the press slide completing its opening stroke. I

As hereinbefore stated, magnet 2! is energized upon completion of the "in movement of carrier B by reason of switch B32 being actuated by dog B2. Upon magnet 2|! thus becoming energized, switch 2I8c in the circuit of magnet 22! is caused to close to initiate closing of the press. Of the other switches in said circuit, switch 220e is in its normally closed position, switch 211] is held closed due to the fact that magnet 21'! is energized while any carrier (in this case, carrier B) is in other than out" position, switches 233c and 2340 are in their normally closed positions, switch 224b is held closed by reason 01 the fact that at that time magnet 224 is in. energized condition, and, it the diecarrier and the dial are in their precise pressing a circuit through magnet 22l, energizing the latter, whereupon switches Hill and 22Ie close,

completing a circuit through and energizing the down solenoid I00. The said solenoid operates valve 3l, causing plunger 33 thereof to move to its lowermost position so that fluid pumped into said valve through pipe 01 may pass from said valve, through pipe 90, into chamber 83, whereby to effect the downstroke of the press.

At this point, it is well to observe that, during the closing and opening of the press, magnet 2l2 must remain de-energized to prevent the closing of switch 212b, which if it occurred during the said portion of the operating cycle, would cause the die-carrier to start moving outwardly in conflict with the closing and opening of the press. The holding of magnet 2 l2 in its de-cnergized condition to prevent such conflict is as- Switch 2i8c remains closed until the down movement of the press slide 24 causes dog 0 to disengage switch SU, mounted on the crown 22 of the press, whereupon the latter switch opens and de-energizes magnet 2 I 9, as'a result of which switch 2l8c opens, thus causing a further break in the clrcuit through magnet 2l2. Upon the completion of the downstroke of the press, switch 22) closes, but switch 2i9c remains open and cannot close until the dog H0 re-engages and closes switch SU upon the completion of the opening stroke of the press slide 24. Hence, it is assured that the die-carrier may only move when the press is open. As will be hereinafter explained, said switches H90 and 22lb also serve to assure that the dial 14 may only rotate when the press is open.

Although switches 2i9c and Hit; serve toprevent magnet 2i2 from becoming energized during the closing and opening of the press. nevertheless, in order to avoid possible conflict, at the moment dog B2 closes switch B32, between magnet 2i2, which at that moment would tend to hold the circuit closed through the carrier motor, thus tending to reverse the carrier and move it outwardly. and magnet 22!, which at that moment should become effective to start the down movement of the press slide 24. switch 2i8b in the circuit of magnet H2 is caused toopen by reason of magnet 2l8 becoming energized immediately upon the closing of the switch 332 by the dog B2. In this way the opening of switch 2l8b operates to de-energize magnet 2l2 independently of the action of switch 22ib. Thus, it may be said that the circuit through magnet 2l2 is broken on the carrier reaching in" position, primarily by the opening of switch 2i8b. and, secondarily, by the opening of switches 22") and 2l9c. the latter switch serving to hold magnet 2 l2 de-energized until the press has completed its closing and opening strokes.

Having the foregoing understanding of the manner in which the various dog-actuated switches function upon die-carrier B reaching its "in" position. the further operation of the press may now be considered. When the circuit through magnet 22I is closed by the closing of switch 2l8c. as already explained, the press slide 24 starts to move downwardly in response to hydraulic pressure established in chamber 89 by reason oi the operation of the down" sclenoid I00 and the valve 91, under the control of the said circuit. Thereupon, the dog H0 disengages and opens switch SU, thereby de-energizing magnet M9, in consequence. not only opening switch 2i9c to hold open the circuit through magnet 2i2, as just explained, but also opening switch 2i9b. thereby breaking the connection which extends through switch B22 between the main take-off line 303 and the side of magnet 2 which is remote from wire 302,

so that. while the said slide 24 is in any position other. than its open position. the circuit through magnet M2 is broken at both ends thereof.

termined "down position or a position wherein the restraint oflered by the blank or blanks being pressed has built up sufiicient back pressure in chamber 89, the said slide is caused to stop its down movement and automatically start moving upwardly. To accomplish this, there are provided two normally closed switches in series in the circuit of. magnet 224. One of these switches, switch SD, is a dog-actuated switch which may be opened by dog iii if the press slide moves downwardly to the said predetermined "down" position; the other switch, switch P8, is a pressure switch which is hydraulically connected to pipe 80 through pipe 90a, the electric contacts As the press slide 24 reaches either a prede- 76 ofsaid'swltch being connected, of course, in the wiring comprising the circuit through magnet 224. The latter switch may be adjusted so that it will open upon thepressure in chamber 89 rising to a predetermined point, so that the press slide may be caused to reverse its movement and start moving upwardly, in the manner now to be described, even though it does not move downwardly sufficiently to operate switch SD.

Upon the opening of one or the other of switches SD or PS, magnet 224 becomes deenergized, thereby opening switch 224!) in the circuit of magnet 22 I, whereby to de-energize the latter, and closing switch 224c in the circuit of magnet 223 to energize the latter, switch 2 l9d in the latter circuit, at that time, being in its normally closed position, and switch 22ic in said latter circuit being closed at the completion of the downstroke of the press slide 24 by the deenergizing of magnet 22L Upon magnet 22! becoming de-energized and magnet 223 becoming energized in the manner just explained, switches Mid and 22le open. thereby de-energizing the down solenoid liili while switches 22311 and 223e close, thereby energizing the up solenoid IIJI. This reversal of the condition of the solenoids I00 and IM operates to shift the plunger 99 of the valve 8| from its lowermost position to its uppermost position. In the latter position of said valve the fluid entering said valve through pipe 91, instead of being pumped into chamber 89, as was the case during the downstroke of the press, is pumped into push-back chambers 92 through the pipe 93. thus imposing pressure on the lower ends of push-back pistons 28 and thereby causing the press slide 24 to start moving upwardly.

It will be seen that, although magnet 22l becomes de-energized upon the completion of the downstroke of the press slide 24 and thereby closes switch Till). the circuit through magnet 2l2 cannot at that time be rc-established for the reason that switches 2l8b and H90, in the latter circuit, still are open and will remain open until magnet 2i9 is energized upon the completion of the upstroke of the press slide 24.

The de-energizing of magnet 224 in the manner Just explained. upon completion of the downstroke oi the press slide 24, causes switch 224d in the circuit of magnet 2|! to open, thereby de-energizing said magnet and. in consequence.

opening switch 2i8a in the circuit or said magnet and closing switch 2l8h in the circuit of magnet 2i2. After such dc-energizing of magnet 2l8, it may not be again energized until the die-carrier that is in the press has moved outwardly and it, or another die-carrier, has moved into the press in a new cycle similar to that thus far described; this because magnet MS may only be energized by the closing of switch B32 as carrier B moves inwardly, or when one of the ment, and hence on the out movement of they die-carrier no circuit will be established through magnet 2I8. It is therefore apparent that switch 2l8b in the circuit of magnet2l2 remains closed during the up movement of the press slide, during the outward movement of any die-carrier, and until some die-carrier has moved inwardly and again energized magnet 2I8 and Thus, although switch opened said switch 2l8b in the manner already 3 described. Notwithstanding the fact that switch 2I8b is closed during the part of the cycle just referred to, nevertheless it is apparent that magnet 2l2 may not be energized to close switch 2l2b, whereby to start die-carrier B moving outwardly, until the press slide 24 completes its upstroke and energizes magnet 2I9 whereby to close switches 2I9b and 2l3c in the manner about to be explained.

As the press slide 24 approaches its uppermost position, dog I I0 engages and closes switch SU, thereby energizing magnet 2I9. One result of magnet 2I9 becoming energized is the opening of switch 2I9d in the circuit through magnet 223, which de-energizes the latter and causes switches 223:! and 223e to open, thus de-energizing up solenoid IOI, whereupon, in the manner already explained, plunger 95 moves to its intermediate position, thus stopping all further movement of the press slide 24. Upon magnet 223 becoming de-energized, switch 223b in the circult of magnet 224 closes, energizing said magnet, whereupon switch 224a in the circuit of magnet 223 opens, thus opening the connections at both ends of the latter magnet, to assure that it may not again be energized and function until the-press has again been closed.

Another result of magnet'2l9 becoming energized, upon completion of the upstroke of the press, is that switches H92) and 2I9c are caused to close, thereupon completing a circuit through said magnet extending from main take-off wire 303 through switch 2I9b, wire 220l, switch CI2, wire 220m, wire 2l2r, switch B22 (then closed because of die-carrier B being in), wire 2I2p, magnet 2I2, wire 2I2n, switch 2Ilc, wire 3), switch 2I3c, wire 320, switch 2l8b, wire 32I, and switches 22 lb and 2 I 90, to wire 302. Upon magnet 2I2 being thus energized, switch 2l2a closes, thus establishing a connection from main take-off wire 303 through said switch 2l2a and wires 2I2l and 2l2m, to function in place of the aboveenumerated connections between main take-01f wire 303 and magnet 2l2, which connections will, of course, be broken as soon as die-carrier B starts moving outwardly, and thus permit switch 1322 to open. Thus, through switch 2l2a the circuit through magnet 2 I 2 is maintained during the entire out movement of thedie-carrier B.

Upon magnet 2 I2 becoming energized, and during the period when it is held energized as just explained, switch 2I2b is opened, and held open, thus establishing a circuit through the out cuit extending from main take-off wire 303 to wire 302 and including switch 2 I21), wire 322, the out winding of the motor of carrier B, wire 325, switch 232d (then held closed because of the fact that out magnet 232 is then energized, and is held energized through the entire out movement of any die-carrier), and wire 326.

Upon the said circuit being established through the said out winding of the motor of carrier B, the latter starts moving outwardly, opening dogactuated switches B42 and B22 and closing dogactuated switch BI2. Upon die-carrier B reaching its outermost position, dog BI opens switch BII and dog B3 closes switch 32!, thus restoring the electric connections of die-carrier B to the same state as the connections of the other live die-carriers of the press.-

In order to fully understand the complete automatic functioning of the press disclosed in the present application, let us assume that after diecarrier B has been started into the press at the beginning of its operating cycle, the operator in charge of die-carrier A, upon completing the loading of the dies thereon, presses selector button switch 305. The pressing of said button switch completes a circuit through and energizes magnet 20I in the same manner as the pressing of the selector button switch 306 by the operator of die-carrier B energized magnet 202 at the bewinding of the motor of die-carrier B, said cirginning of the operating cycle of carrier B.

"The efiect of such selection of carrier A, however, cannot function immediately to energize magnet 2| I in order to operate carrier A, for the reason that a circuit through the latter magnet to energize it may only be initiated through selection-maintaining take-off wire 3I5, which, while carrier B remains in the press, is dead, due to the fact that switch 2I1e, in the circuit through said wir 3 I5, is held open because magnet 2 I 1 is energized during the entire period when carrier B or any other carrier is in the press. However, as soon as carrier B reaches its outermost position in the cycle of operations just described, dog BI engages and opens switch Bll, thereby de-energizing magnet 2i! and closing switch 2IIe. Therefore, in view of the fact that carrier A has been pre-selected as the next carrier to go into the press, and as such pro-selection has been primarily stablished in magnet 20 I the closing of switch 2I1e in the manner just described completes a circuit from main take-oil wire 303 through said switch 2I'Ie, wire 3I5, wire 3I6, switch 20Ic, wire 2Ill, magnet 2, wire 2Iln, switches 2l2a, 2I3c, wire 320, switch 2l0b, wire 32I, and switches 22Ib and 2l9c, thus energizing magnet 2H and closing switch 2l lb in the circuit through the in winding of the motor of die-carrier A, so that, immediately upon diecarrier B reaching its outermost position, diecarrier A automatically starts moving inwardly. Thereafter, the function of the various parts of the electric circuit to control the movement of die-carrier A into andout of the press is the same as has already been described with respect to die-carrier B.

It is to be understood, of course, that all of the die-carriers have similar electric apparatus and wiring controlling their operation, so that the foregoing description of the operation of diecarrier B and of the manner in which die-carrier A would automatically function upon the-completion of the outward movement of die-carrier B should sufiice as an illustration of the mode-of operation involved where other die-carriers are

Images