US2665654A

US2665654A - Feed mechanism and control for continuous stock material

Info

Publication number: US2665654A
Application number: US123730A
Authority: US
Inventors: Lyon George Albert
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-10-26
Filing date: 1949-10-26
Publication date: 1954-01-12
Anticipated expiration: 1971-01-12

Description

Jan. 12, 1954 LYON 2,665,654

FEED MECHANISM AND CONTROL. FOR CONTINUOUS STOCK MATERIAL Filed Oct. 26, 1949 r 4 Sheets-Shea} l PQMA &

In 1 517 T02" Hffys G. A. LYON Jan. 12, 1954 FEED MECHANISM AND CONTROL FOR CONTINUOUS STOCK MATERIAL 4 Sheets-Sheet 2 Filed Oct. 26, 1949 Jan. 12, 1954 LYON 2,665,654

. FEED MECHANISM AND CONTROL FOR CONTINUOUS STOCK MATERIAL Filed Oct. 26, 1949 4 Sheets-Sheet 3 "J 10" y 16 I 1 45 1 1 w wan M Fi /5 Jan. 12, 1954 G. A. LYON 2,665,654

FEED MECHANISM AND CONTROL FOR CONTINUOUS STOCK MATERIAL Filed Oct. 26. 1949 4 Sheets-Sheet 4 I: 51% El 1 W H w 2 19m mm, M a 39 1765 i 2 9 c ii 14; 1%

Q 56 x //M 66 A? Lg: V X07149 I "H "'h 6@ I |h.. =1; ii 142 I V 5 g? y II M f a 5;;

fnz s rzfar GEO/ yaA [fie/ 2 ,Zya'z Fif 5 Patented Jan. 12, 1954 UNITED STATES PATENT OFFICE FEED MECHANISM AND CONTROL FOR- CONTINUOUS STOCK MATERIAL George Albert Lyon, Detroit, Mich;

Application ctoberf26, 1949,. SerialNm 123;730.

Claims. 1

Another object of my invention is to provide a novel andeificient form of control for feeding sheet material to a work performing apparatus, actuated by operation of the apparatus. duringits variouswork performing operations, and so constructed and arranged as to automatically and accurately feed predetermined lengths of sheet material in. a more positive and facile manner than formerly.

"Still another object of my invention is to provide a reciprocably movable table. with gripping means thereon to positively grip the sheet stock, with a novel form of operating and control means therefor operable to effect positive gripping of the sheet stock and translational movement thereof to. a working station, operable by the position of the table and operating parts of the working station with respect to the stock to be worked upon.

Still another object of my invention is to provide a coordinated control for feeding stock to a press, so arranged as to effect translation movement of the stock toward the press upon predetermined positions of the working head thereof.

Still another and more detailed object of my invention is to provide a novel and improved form of feed adapted to feed sheet stock to apress' of the type having a vertically movable cushion coming into engagement with the material during the working stroke of the press, and including means for gripping the stock and translationally moving it-toward the press into position to be worked upon, together with fluid valves controlling the various gripping and. feeding operations, and actuating. and. control means therefor operated by the various moving parts of the press and feeding de vice.

In carrying out my invention I provide a translationally movable. table to support the sheet material to be worked upon and provide clamping devices on the table together with means for positively moving the clamping devices into and out of engagement with the material to be worked upon. I'also provide means for moving the table toward and from the press and provide solenoids tocontrol. operationof the gripping and feedin means together with a. novel form and arrangemerit of switches on the press and the feeding mechanism, controlled by movement of the press toward and from the work and connected to operate the solenoids at predetermined time intervals dependent upon the position of the cushion of the presswith respectto the stock to be worked upon.

This invention is a continuation-in-part of an application SerialNumber 100,365, filed by me on June 21, 1949, and entitled Continuous Web Feeding'Mechanism.

These and other objects of my invention will appear from time to time as" the following specification proceeds and the reference to the accompanying drawings wherein:

Figure 1 is a view in side elevation of a stock feeding mechanism constructed in accordance with my invention;

Figure 2 is a top plan view of the device shown in Figure 1; showing: the sheet supported thereon, with a part thereof. broken away in order to more clearly illustrate certain details of the. feeding mechanism therefor;

Figure 3 is a view inside elevation of the feeding mechanism shown in Figure 1, drawn to a reduced scale and showing the feeding mechanism at the receiving end of a press adapted to work upon material supplied thereto;

Figure 4 is an enlarged fragmentary transverse sectional view taken through the mechanism for clamping the stock to the table of the feeding mechanism, and showing the clamping mechanismin a released position;

Figure 5 is afragmentary perspective view of apiece of material showing how the material is crimped by the clamping mechanism during the feeding operation;

Figure 6 is a fragmentary front end view of a hydraulic press diagrammatically showing the switches for controlling operation of the feeding mechanism; and

Figure 7518 a diagrammatic view showing the wiring diagram of the switches operated by the press and feeding mechanism and the solenoids controlling operation of the feeding mechanism.

In the-drawings [0 generally designates a feeding mechanism adapted to feed sheet stock II to a working table'or anvil 12 of a hydraulic press 13 which may be of a well known form, adapted to sever the stock and shape it to a desired form.

The feeding mechanism H] is clearly shown and.

described in my applicationserial Number 100,365

of which this application is a continuation-inpart, so need only herein be shown and described insofar as is necessary to make my present invention readily understandable.

The feeding mechanism In includes a frame structure I4 having a vertical longitudinally extending guide structure I5 extending along the top thereof for a portion of the length thereof, and forming a support and guide for a translationally movable stock feeding table I6, spaced thereabove and mounted thereon for slidable movement therealong. The table I6 has a central vertically extending web I8 depending therefrom and supported and slidably guided in the guide structure I6, as shown in my application, Serial Number 100,365.

The table I6 is translationally moved along the guide structure I5 by means of a longitudinally extending double acting cylinder I5, mounted on the top of the frame structure I4 in longitudinally spaced brackets 26, 2t projecting upwardly from the top surface of said frame structure. A piston rod 2 I, extensible from the cylinder I9 is pivotally connected at its forward end to an ear 22 extending laterally from the Web I8, to move said plate and the table I6 along the guide structure I5, upon extensible or retractable movement of said piston rod with respect to the cylinder I9.

Fluid under pressure such as air is admitted to the head end of the cylinder I9 to extensibly move the table I6 toward the press I3 by means of a valve 25 and a conduit 26 connected to the head end of the cylinder I9. The valve 25 may be any well known form of fluid or air valve, operable by depressing either one of two plungers 3|, 3i to admit air to or release it from the conduit 26 and cylinder I9, and is no part of my present invention, so need not be shown or described in detail herein.

A solenoid 21 having an armature 28 is provided to operate the valve 25. Said armature is pivotally connected at its upper end to one end of a lever arm 29 through a link 30. The lever arm 29 is pivotally connected adjacent its opposite end between a bifurcated fulcrum support 32, and has gaging the underside of the lever arm 29 and en- I circling a vertical rod 34, extending through said lever arm adjacent its center, is provided to extend the armature 28 and open the valve 25, for release of fluid from the head end of the cylinder I9. A nut and washer indicated by reference character 35 is provided to hold said lever arm to said rod and to preload the spring 33.

Fluid under pressure is admitted to and released from the piston rod end of the cylinder I3, to translationally move the table I 6 away from the press I 3 through a fluid valve 31. The valve 31 is like the valve 25 and is opened by a solenoid 39, to admit fluid to the piston rod end of the cylinder I9. A pressure line or conduit 4I connects said valve to the piston rod end of the cylinder I 9.

The table I6 has a clamping lever 43 pivotally mounted on each side thereof in laterally spaced relation with respect thereto. The clamping levers 43 each have an inwardly extending crimping end portion 44 movable to crimp and engage the edges of the sheet stock into V-shaped notches 45, 45 formed in the edges of support plate 46 (see Figure 4) This forms indentations 4'1 in opposite edges of the stock as shown in Figure 5 and 4 assures positive feed of the stock. to the press I3 upon translational movement of the table l6. The clamping levers 43, 43 on each side of the table I6 are of a similar construction and are supported and operated in a. similar manner, so one only need herein be shown and described in detail. Each lever 43 is herein shown as being pivoted intermediate its ends, but adjacent the crimping end 44 thereof, between two spaced ears 4B, 48 formed integrally with the support plate 46. The plate 46 is adjustably mounted in a slot 49 formed in the table I6, and is suitably secured thereto and affords a means for adjusting the po sition of the crimping end 44 of the clamping lever 43, to the various widths of stock desired. The outer end of the lever 43 is pivotally connected between a bifurcated end portion of a connecting member 50, threaded on the upper end of a rod 5|. The rod 5I is slidably guided in a support plate 53 extending laterally from the support plate 46 and table I6. A spring '54, encircling said rod, is interposed between the bottom of the support plate 53 and a washer 55, held to said rod by lock nut 56, 56, to yieldably hold the crimping end 44 of lever 43 out of engagement with the edge of the stock.

A cylinder 59 is mounted on the bottom of the plate 53 and depends therefrom and has a piston rod 60 extensible from the upper end thereof, to pivot the clamping lever 43 and hold the crimping end 44 thereof in engagement with the edge of the material. The piston rod 66, as herein shown, has an enlarged end =6I having an evenly rounded upper face forming an abutment surface engageable with the underside of the lever 43, intermediate its ends, to pivot said lever against the spring 54, and move the crimping end 44 thereof into crimping engagement with the sheet material.

The fluid pressure cylinder 59 is herein shown as being a double acting cylinder, and the admission and release of fluid under pressure to and from both ends of said cylinder is controlled by a fluid valve 63, operated by a solenoid 64 through a lever arm 65 pivoted thereto, in the same manner the valves 25 and 31 are operated by their associated solenoids. The valve 63 is connected to the head ends of the

cylinders

59, 59 by means of a conduit 66 connected to a trans versely extending pipe 61 and

conduits

69, 69, to supply fluid under pressure thereto and move the clamping levers 43, 43 into clamping engagement with the stock on the table I6. Said valve is connected to the piston rod ends of said cylinders through a conduit I6, a transversely extending pipe II and conduits I2, I2, connected from opposite ends of said pipe to the piston rod ends of said cylinders.

The sheet material is supported as it passes to the feeding table I6 on a transversely extending roller I3 at the entering end of the machine and journalled at its ends in bearing boxes I4, I4 mounted on the upper ends of upright support plates I5, I5 extending upwardly from opposite sides of said frame structure. Guide rollers I6, I6 are mounted in advance, but adjacent the roller I3 on vertical spindles TI, TI, extending upwardly from the plates I5, I5, to engage opposite sides of the material and align it with the table, during the feeding operation. Gibbed guides I8, 78 extend along opposite sides of the table I6 and the gibs thereof extend over the edges of the stock, to guide the stock along said table, and also to form a guide for the stock as the table is retracted to a Starting position, to

again feed the, sheettmateri'al'intoz the I3;

When the tables. Ifi ls in a retracted position; the: crimping I ends-44 44 of the: clamping levers.

43, 43 may: first be broughttintoaengagement with the edges'oftthe sheetiistoclo and positively hold it. in, engagement with, the. table. I;6:.. Fluid;

under pressuremay then: be admitted: to the head end. of" the cylinders I 9 to: extendjthepiston rodZI therefrom. and advance the. table It along the guide. structure I5, carryingxthesheet stock with itxand feeding it to the press" I3.. Eeed ing movementotthe. table It maybe so correlated' with movement of a working'head 19 ct; theapress' I3, thatthe piston rod. 2| will beat the end of itsstrokeandl the table I6 will. be

admitted to the piston rod ends ofthe cylinders I9, I9 and. released, from the headiendsof said cylinders, to retractably move the feeding table I6. into position to again grip opposite sides of the sheet stock material for advancing to the. press I3. It is obviousthat' the length oftranslational movement of the feeding table It may be varied by changing the; effective stroke of the piston rod 22, asby varying the volume of fluid admitted, to and released from. opposite ends'of said. cylinder;

The press may be ofany well known form, preferably ofthe hydraulic-type and, as shown in Figures 3 and 6, has a workinghead 19 suitably guided between two verticalcolumns 83, B3. Said working head hasthe cushion 80, mounted thereon, to first come into engagement with and to. hold the material being'worked upon and has a ram (not shown)" vertically movable with respect to said cushion, which performs the working operations.

As herein shown two vertically spacedcams 84' and 85 are mounted on the workinghead I9 adjacent one column 83-; The cam. 84 is shown inFigure 6 as' extending vertically along the working head I9 in parallelrelation' with respect to the column 83 and as having sloping upper and lowerend portions. The cam 841s adapted to engage inwardly extending operating levers- 86 and 81 oflimit switches 88' and 89 respectively. Said limit switches are-mounted on the right handcolumn 83 in vertically spaced relation with" respect to each other.

The limit. switches 88 and. 8.9 may be of anywell known form and are no part of my present inventionso need not herein be shown. or describedv in detail"; The limit switch. 88, as'shown in. Figure 7, has two contacts 90 and 9I, the contact QO'being closed-when'thetlever 8B is engaged by' the cam184 at the completionofi'the down stroke of theworki'ng head T9,:and the contact 9I being closed when the cam 841mves out of engagement with the lever 86'; The. limit switch 89 is also so arranged that a contact 93 thereof is closed when its operating lever 81 is engaged by the cam 84 upon the return strokeof theworking head I9, and'remains opened whensaid cam engages said: lever uponthe down stroke of said working head.

sclimit svzitch. 95:. having: an. operating 98; extending; therefrom and adapted. to: be. en:

gagedbythecam at the end of the up. strokea of: the pressris .li'kewise'mountedzon' the right hand column 83 above the limit switches 88 and 89; and'has a contact: 91" which normally remains open and is. closed uponz engagement; of; the; cam. 85 with the operating lever 96. thereof on the extreme upper ends of thestrokesv of the-working.

head. I9, to control the. energization of the Working. or return cycle.- of the press. The limit switch. is shown in Figure 7 as being: con:-

nected. in" series with a limit switch 99. mounted.

prevent energization thereof until the feeding table I6 is: at the extreme end ofits feeding stroke.

A limit switch I03 is. mounted on the guide structure I5 adjacent the entering end thereof.

and is adapted to be. closed at the extreme end of return travel of the feeding table Ifiand con trols energization of, the solenoids: $4, 64 and gripping of the material withclarnping levers 43,. 43. The limit switch I03 is like the limit-switches previously mentioned and has anpoperating lever I 04 projecting upwardly therefrom, adaptedtto. be-engaged by the end .of' a trip bar I05, extending rearwardly from the web I8, to close a contact. I 06 of said switch and close a circuit to a coil I 01 of a rela I09, and. energize said coil, and close contacts, IIII, III and H2 of said relay, to complete thecircuit through a coil H3 of the solenoid 64, and cause the clamping levers 43, 43 to come into clamping engagement with the sheet materialonthe table I6.

In. Figure 7, a. positive conductor H4 and a negative conductor II5 are shown. A starting switch II6 is shown as being connected in said positive and negative conductors inseries with contact II9 of a. relay I2I and a coil I22 of said relay. The switch H5 is herein shown as being a. push button type of switch, the contacts of which open upon energization of the circuit and. removal of the hand therefrom. The contact H9 is closed when. the. coil I 22 is deenergized and opens when said coil is energized. Closing starting switch I I6 will thus energize the. coil I22 and. open the contact II9. It will close contact I23.- of said relay in conductor I24 connecting said coil withthe conductor I I4 through a stop switch I25. It will also close contact I26 in series. with the limitswitch 89 and contact I21in series with the limit switches. 35 and. 99-. The. push button switch I25. connects the. conductor l24, contact I23 and coil I22 of relay I2I to. the positive line I I4 and, is normally closed. Saidswitch I25 serves todeenergize the. control system and stop operationofthefeeding mechanism when opened, by breaking, the circuit to the coil I22 of the contactor I2.I, and closes as soon as the hand is removed therefrom.

A. conductor I3I connects the positive line II4 with the coil III! of the relay I09 through the y starting switch. I I6, to energize said coila-nd close the contacts o1'saidrelay, upon closing of said switch II6. A conductor I32 connects the return side of the coil I9! to the contact 9| of the limit switch 88. Said coil I! is connected to the negative line through said switch 86 and a conductor I 34. The limit switch I93 is connected from the positive line II4 to the conductor I3I, and serves to energize the coil I91 of the relay I99, at the end of return travel of the table I6 when the starting switch I I6 is open. Energizing coil I 97 of relay I99 will close the contacts II9, III and H2 of said relay and energize the coil I I3 of the solenoid 64 to bring the crimping ends of the clamping levers 43, 43 into clamping engagement with the sheet material. As the trip bar I95 moves away from the lever I96, the switch I93 will open. The contact II9, however, will complete the circuit to the coil I91, and will lock said relay in a closed position, until cushion 89 moves into engagement with the stock, and the cam 84 breaks the circuit through the contact 9I. At this time the circuit to said coil I9! will be broken and the clamping levers 43, 43 will move to disengaged positions. The contact 99 will then be closed, to complete a circuit to a coil I39 of the solenoid 39, to energize said solenoid and actuate the back stroke of the table I6.

The contact 93 of the limit switch 89 is closed upon engagement of the cam 94 with the lever 81 during the return path of travel of the press. This closes a circuit to a coil I49 of the solenoid 21, through the contact I26 of the relay I2 I. This will effect opening of the valve 25 and translational movement of the table I6 toward the press I3, as the working head 19 thereof moves upwardly along the

columns

83, 83.

In starting operation of the press and feeding device, the switch I I6 may be closed by hand, energizing the coil I22 of the relay I2I. This will close the contacts I23, I26 and I2! of said relay and will open contact II9 thereof. The switch II6 will then open when the hand is removed therefrom, the switch I25 being closed. Assuming that the working head of the press is in its extreme uppermost position when starting the press, as shown in Figure 6, and the feeding table I6 is in the extreme extended position shown in Figures 1 and 3, the cam 85 will close the limit switch 95. The trip bar I9I will also close the limit switch 99. This will energize the working cycle of the press, through suitable control devices, not herein shown or described since they are no part of my present invention.

Upon downward movement of the press the cam 84 will first engage the lever 81 of the limit switch 89, but due to the construction of said switch as previously explained, said switch will remain open. As the cushion 89 engages the stock II, the cam 84 will come into engagement with the lever 86 of the limit switch 88. This will open the contact 9! of said switch and deenergize the coil I9! of the relay I99, opening the contacts H9, III and H2 thereof. Opening of contact N9 of the relay I99 will deenergize the coil H3 of the solenoid 64, allowing. the springs 54, 54 to disengage the crimping ends 44, 44 of the clamping levers 43, 43 from the stock. The contact 90 will then close. This will energize the coil I39 of the solenoid 39 and open the valve 31 to supply fluid under pressure to the piston rod end of the cylinder I9, and retract the feeding table I6 along the guide structure I5. The cam 84 is of sufficient length tohold the contact 99 of the switch 88 closed until the table l6 moves to an extreme retracted position and the trip bar I95 comes into engagement with the arm I96 of the limit switch I93, closing the contact I96 of said switch. At this point the cam 84 will be moved out of engagement with the lever 86 and the contact 99 of the limit switch 88 will open, while the contact '9I thereof will close. Closing of the contact I96 of the switch I93 will energize the coil I91 and close the contacts II9, III and H2 thereof. This will energize the coil II3 of the solenoid 64 and eifect engagement of the clamping levers 43, 43 with the stock. As the cam 84 moves upwardly a further distance it will come into engagement with the lever 81 of the limit switch 89, closing contact 93 of said switch and completing the circuit through the coil I49 of the solenoid 21 through the contact I26 of the relay I22, energizing said solenoid and effecting opening of the valve 25, to supply fluid under pressure to the head end of the cylinder I9 and translationally move the feeding table I6 and the stock II clamped thereon toward the press I3. At the end of feeding movement of the table I6 the end of the trip bar I9I will engage the lever I99 of the limit switch 99 and close said switch and initiate another working cycle of the press, assuming the cam has closed the switch 95.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. In a feeding mechanism and in combination with a press having a vertically movable cushion and head, supporting structure means carried by said supporting structure for feeding stock to the press comprising a table and gripping means thereon for gripping the stock, means for moving the gripping means and table toward and from the press, two fluid valves controlling movement of the gripping means and table toward and from the press, a third fluid valve controlling engagement of said gripping means with the stock, a separate solenoid operatively connected with each of said valves, to operate the same, and control means for said solenoids and valves energizing saidsolenoids in a predetermined sequence by operation of said press and feeding mechanism comprising two spaced switches on the press, each being connected with one of said solenoids to effect the sequential energization thereof, and the operation of said two fluid valves, a third switch on said supporting structure and connected with the solenoid for operating said third fluid valve, a cam movable with the cushion and head of the press to engage said first two switches in a predetermined sequence and energize the associated solenoids at predetermined points in the cycle of operation of said press, another switch on said press closed upon extreme retractable movement of the cushion and head and controlling energization of the working cycle of said press, a switch operating member on said table for operating said third switch and energizing the solenoid associated therewith at the end of the return stroke of said table to effect gripping of the stock, and a further switch on said supporting structure closed by a switch actuator on said table upon movement of said gripping means to an extreme advance position, said further switch having its contacts connected in series with the contacts of said last mentioned switch on the press for energizing the working cycle tof the press upon movement of the gripping means to the extreme end of the feeding stroke thereof.

2. In a feedingmechanisin and in combination with a press having "a vertically movable cushion and head, supporting structure, means carried by the supporting structure for feeding stock to the press comprising a table movable toward and from the'press and gripping means on said table for gripping the stock, other means for'translationally moving the tabl'e and gripping means toward and from the press, two fiuid valves, one controlling translational movement of the table and gripping means toward the press and the other controlling translational rnovem'ent of the table and gripping means from the press, a third fluid valve controlling engagement of said gripping means with the stock, a separate solenoid operatively connected with each of said valves, to operate the same, andlsequentially operated control means for said solenoids and valves comprising two spaced switches on the press, each connected with one of said solenoids to sequentially energize saidsolenoids, a switch on the supporting structure connected with the solenoid ifor operating said third fluid valve, to energize said solenoid, a cam movable with the cushion and head of the press to sequentially close said switches on the press, a switch actuator movable with said gripping means to efiect closing of said switch on the supporting structure, upon movement of said table and gripping means to a retracted position, to energize said solenoid for operating said third valve and effect engagement of said gripping means with the stock, a relayhaving a coil connected in series with the contacts of said switch on the supporting structure and energized upon the closing of such switch, the switch on said press energizing the solenoid operating the valve controlling retractable movement of said feeding means, having contacts in series with the coil of said relay to energize the same upon the closing of said switch on the supporting structure, and also having a second set of contacts connected to energize said solenoid controlling retractable movement of said feeding means upon opening of the first mentioned contacts thereof, another switch on said press closed upon extreme upward travel of said cushion and head and controlling energization of the working cycle of said press, and a further switch on said supporting structure, closed by movement of said table and gripping means to an extreme advanced position, said further switch having its contacts connected in series with the contacts of said switch on the press for controlling the energization of the working cycle of the press, and preventing energization of the working cycle of the press until said gripping means has reached the extreme end of its feeding stroke.

3. In a control for a stock feeding apparatus adapted to feed stock to a press having an anvil and a cushion movable toward and from said anvil, said stock feeding apparatus having a table, means for translationally moving said table toward and from the press, gripping means on said table, means for moving said gripping means into gripping engagement with the stock, to feed the stock to said press upon translational movement of said table toward the press, and means operated by vertical movement of said cushion to control feeding movement of the stock thereto including a first solenoid controlling travel of said table away from the press, a second solenoid controlling "travel of said table toward the press,

a third solenoid controllingengagement of said gripping means withthe stock, a cam mounted #onthe cushion of the press-and movable therewith upon vertical movement of "said cushion, a firstswitch mounted on the press, said switch having two :conta'cts oneof which is closed and the other of which is open during movement or said table toward the press, a relay having a coil connected with the closed contact 'of said switch and energized upon closing ofsaid 'contact, the open'conta'ct of said switch being connected with said first solenoid to energize said solenoidavhen closed, said relay having contacts connected with said third solenoid, to hold said solenoid closed, and said first switch having an operating lever connected and positioned to be engaged by said cam upon engagement of said cushion with said anvil, to move said switch to open said closed contact and break the circuit "to said relay coil, causing opening thereof and release of said gripping means, and to close said open contact and' close the circuit to said first solenoid, energizing said solenoid, to effect travel :of said table away from the press, and a second switch spaced from said first switch on said press and having an operating lever connected thereto and positioned to be closed by engagement of :said cam urmnupward travel of said ram and cushion only, to close the circuit to said second solenoid, and energize said second solenoid and effect travel Olf said table toward the press, said first switch closing the circuit to the coil of said relay upon "disengagement of said cam from its operating handle, to energize and close said relay upon upward travel of said cushion and disengagement of said cam from said first switch,

and a third switch on the feeding apparatus closed by engagement with said table at the end of retractibletravel thereof, to energize said third solenoid, to effectengagement of said gripping means with the stock prior to the feeding stroke of said table.

4. In a press having a vertically movable reciprocating cushion and head, a supporting structure, a stock feeding mechanism carried by said supporting structure and arranged to feed stock to the press and including a reciprocably movable table, gripping means on said table for clampingly engaging the stock, means moving said table toward and from the press, means engaging said gripping means with the stock, valve means controlling the engagement of said gripping means with the stock, valve means controlling movement of said table toward the press, other valve means controlling return movement of said table, and individual solenoids connected with said valve means to operate the same, the improvements comprising a relay, a cam movable with the cushion and head of the press, two spaced switches on the press and operated by said cam in a predetermined sequence, one being associated with said relay and having a contact connected to energize the coil of said relay when closed and a second contact closing upon opening of said first contact, to energize said solenoid effecting movement of said feeding mechanism from the press, the other of said switches being associated with said solenoid controlling movement of said table toward the press and energizing the same upon the closing of said relay, and a switch on the supporting structure closed by movement of said table at the end of return travel thereof and having a contact in series with the coil of said relay and the first 11 contact on said one switch, said first contact of said one switch closing upon the engagement of said head with the stock, and said switch on said supporting structure closing at the end of return travel of said table and. completing a circuit through the coil of said relay and the first contact of said one switch to close said relay and maintain said relay closed and also to enersaid table toward and from the press and other means moving said gripping means into engagement with the stock, a first valve controlling engagement of said gripping means with the stock, a second valve controlling movement of said table toward the press, a third valve controlling return movement of said table, and individual solenoids connected with said valves to operate the same, the improvements comprising a relay, a cam movable with the cushion and head of the press, two spaced switches on the press and operated by said cam in a predetermined sequence, one of said switches being associated with said relay and having a first contact connected to energize the coil of said relay when closed and a second contact closing upon opening of said first contact to energize the solenoid operating said third valve and effect return movement of said table, the other of said switches having one contact energizing said solenoid operating said second valve controlling movement of said table toward the press, a switch on the supporting structure closed by movement of said table at the end of return travel thereof and having a contact in series with the coil of said relay and the first contact on said one switch, said first contact of said one switch closing upon engagement of the cushion with the stock and completing a circuit through said switch on said supporting structure to energize the coil of said relay and maintain said relay closed and hold said gripping means in engagement with the stock during travel of said feeding means toward the press, a third switch on said press closed upon extreme upward travel of said head and controlling energization of the working cycle of the press, and a further switch on the supporting structure closed by said table at the end of its feeding stroke, said last mentioned switch having contacts in series with the contacts of said third switch on the press and preventing energization of the working cycle of the press until said table is at the end of its feeding stroke.

GEORGE ALBERT LYON.

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