US1515774A

US1515774A - Method of and apparatus for automatically stopping automatic presses

Info

Publication number: US1515774A
Authority: US
Publication date: 1924-11-18
Anticipated expiration: 1941-11-18

Description

Nov. 18, 1924. 1,515,774

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATIC PRESSES Filed Sent. 14 1921 6 Sheets-Sheet l VENTOR A. L. ONE-5 Arm/M578 WITNESSES Nov. 18, 1924. 1,515,774

1.. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATIC PHESSBS Filed Sent. 14 1921 6 Sheets-Sheet 2 INVENTOR L. L, Jon/5.5

fllwuj A TTORNEYS L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATIC FRESSES Filed Sent. 14 192; 6 Sheets-Sheet 3 INVENTOR All .dozvas,

/ TNESSE A ITO/HIE Y8 Nov. 18, 1924. 1,515,774

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATIC PRESSES v Filed Sent. 14 192 6 Sheets-Sheet 4 v K\\\ l WITNESSES I EN TOR I, L.L ONES A TTOR/VEYS Nov. 18, 1 1,515,774

' L. L. JQNES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPKNG AUTOMATIC PRESSES Filed Sent. 14 N12 6 Sheets-Sheet 5 WITNESSES lM/E/VTO}? 7/4. 1, arm 56 i 4 a t C A TTOHNEYS Nov. 18, '1924. 1,515.774'

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATIC PRESSES Filed Sent. 14 1921 6 Sheets-Slgetfi 4&9 74

INVENTOR WITNESSES 11.4 .JON

Patented Nov. 18, 1

UNITED STATES; PATENT OFFICE.

LYMAN LLEWELLYNJ'ONBS 0F SEATTLE. WASHINGTON.

METHOD OF AND APPA Application filed September 14, 1921.

To 1111' whom 51- may 3c it known that concern:

LYMA N; LLE pLLYN JONES, it citizen of Canada, and "ti resident of Seattle, in the county of King' and stete of \Vashington,

have invented certain new :mzl useful improvements in "Metho'd s' of and Apparatus for AutomaticaHy'Stopping Automatic Presses, of

is a specification.

which the following My invention relates to improvements in stop-motion mechanism, only in the construction,

ib d endjfdm ed,

arrangement herein but also in the meth the operation thereof;

and it consists not q etwni n 0d oil accomplishing vention is to provide means i r, eutqmetrcally stopping an automat c "or, c'ptl i e r type of press for stumping tin ;c

the happening a like, upon of 21 number or false o anf e. :cess1\ -ely' thick ging of the can top" of thescrap chute'.

ler'idjtheifz esm g If" A further and most, import rr tobje'ct pi the invention j is, to provid mally;

til a strain beyond a as described, in [the] operet'v e, is imposed on the pressthrough i t slse 4' e es-Lees pre e rmined tioning, whereby the, starting le iger l s dfi lflefll a single operatorican of such presses.

Other objects and pear in the ence being had to the ings, in whicli:

, ,oi Ln-" L nirention is to f' l command 7 a --number advantages 3p followin s ecificati'on refer- D r 7 r accompanying, draw} Figure l is a perspective zie vofengulines, illustrating invention in heavier press. light 6'11t' 'o'f, the lines,

Figure 2 is a similar vie'w f of thzit por- Lion-of the press vindicated'ibyjtliei arrow,,a

in Figure 1,

Figure 3 is a vertical section of the-tin strip contact which strips fed Fig. 3 structure in Fig. 3.

Figures 4, 5 and 6 parts of the tin -strip gauges the size of. tin into the machine,

is a detail plan-mew, o f the are CIELAILVIEWS of contact disassembled,

sticking; of the die-.in thfe' ifiblk; t li i c liig RATUS FOR AUTOMATICALLY STOPPING AUTOMATIC PRESSES.

Serial no; 500,717.

Figure 7 is a cross section, taken substantiallypn the line 77 of Figured, illustrating 'the, construction of one of the junction blocks,.'

"Figure 8 is a perspective View of the can lid discharge chute of the press, also illustrating the disk by means of which the lid edges are curled, r

a Figure!) is a cross section on the line 9-9 of Figure 8, illustrating the construction ofthe kniie-ed e contact foriclosiiig an electrical'cir'cuit en theflli'ds jam in the chute,

Figure IO 'is 'zi perspective"view oi the tin lscrap'l discharge chute also shown at the righpnf Figure 2) i l l i is triiting the posi} t i'oi rpf the' 'elec' eircnitminei fme' 1 tii of the totem Ti r m s'ii nis idi reti ng i fi ms;-

li-l DIL. r h u 2 nd l figur 83se wire rf ileeip r fi; irbfl qo i; t sp nesepo e ili'gimdeof operates and he li t me ,e ds 396? ipp rat ns f h invent oni'rxiey jkrio i' i'i'. The, press coinpris'e's at frame 1', niith e. rack 2 Ioii which the tir'ifstr'ipssT arepile d, in. readiness to bcl"laced on' the'shelfor ledge 3, as shown in. g refl this shelf or ledge; single sheets of tir'riiripicked up by's'uction cups 4, fed l t' h l' e wi I'eege iw '.(F 7 of the pressend-"th'en to "the righrio eijthedie 5 ,(see Fig; l0) t-o be z ctedon by the punch or,]dol1y'6,' see Figsfl and 2), and: thus fproduoe tin cen ,tops 15, two of which are shown thefdischarge chute 7 in Figure 8.' The mechanism by which the tin sheets are fed intothe press includes pusherfrods 4 (Fig. 2) which hare heads 4 fitted with glen-011549 to properly enga'gef the slieets'for the purpose stated. The scrap tin is carried away by the scrap chute Lit) lit)

8 (see Fig. 1.) into which tlie'metal is kicked by the properly timed impeller 9, shown in Figure 2. The construction of the scrap chute 8 includes the opposed angle irons S which provide a supporting frame work for the chute proper 8"; (Fig. 1'). Situated at the left and right respectively of the chute (Fig. 10) are members 8 and 8 for functioning to properly guide the scrap 10 until the chute portion 8 is reached.

The press is subject to a number of maloperations, which the invention is designed to remedy to the extent of promptly stopping the press so that the cause of such operation may be removed. Such causes are the introduction into the machine of two plates T or of an excessively thick plate, sticking of the metal on the die 5 due to improper sharpening of the latter, clogging of the chute 7 by can tops, and clogging of the chute 8 by pieces of scrap metal.

The tin strip contact 10 comprises a plunger with a ball-end 11, normally pressed down by the spring 12 (see Fig. 3) so that a sheet of tinT must be forced into position therebeneath after having been picked up by the suction cups 4 in Figure 2. A tin plate of normal thickness simply raises the plunger 10 without bringing the

contacts

13 and 14 into engagement, but when a plate of unusual thickness (see dotted lines ig. 3) or two plates are forced under the ball 11, the

contacts

13 and 14 will then .be brought into engagement and short-circuit the electro-magnet 15 (Fig. 1) which in turn release the lever 16 so thatth'e press is stopped. The lever 16 falls by gravity against the rubber cushion 17.

It is necessary to understand the electrical circuit which embraces the electro-magnets 15, and which is affected by the closure of the

contacts

13 and 14. A suitable source G furnishes electrical current, one wire 18 being grounded to the frame 1 of the press, another wire 19 running to the binding screw 20 of a metal ring 21 on one of two junction blocks. A lamp L is connected in the wire 19 for the purpose of providing a resistance. A wire 22 runs from the binding posts 23 on the junction ring 21, to one of the binding posts 24 of the electro-magnets 15 (see Fig. 16) the other binding post being grounded to the iron base 25, and so to the frame of the press as indicated in Figure 1.

Under normal conditions, i. e. the proper operation of the press, current flows from the source G, through lamp L over wire 19, junction ring 21, magnets 15 to ground at the frame, returning therefrom over wire 18 to the source G. The resultant energization of the electro-magnets 15- is sufiiciently strong to maintain the attraction of the starting lever 16 through the normal jarring of the press due to the operation thereof.

An abnormal jar \villshake the lever 16 loose so that it falls and stops the machine.

The closure of the contacts 13 and 14 (described above). short circuits the electromagnets 15 with the same result, current then flowing alon the following path: From the source ir over wire 19 to the binding post20 and ring 21 of the first junction block, out at binding post 26, over wire 27 through the binding post 28 of the metal ri 29 of the second junction block, out at bin ing post 30, over wire 31 to the contacts 14, from thence to the contact 13 (now in engagement) and back to the negative pole of the source G through the ground connections and wire 18.

The tin strip contact comprises a metal bushing 32 with threads at the bottom and a non-circular head by means of which the bushing is screwed into a suitable opening in the press frame. This bushing has internal bores of several sizes; the bore 33, which accommodates the plunger 10, is tapered, the bore 34 is larger than the latter, and the bore 35 is threaded to receive the insulating plug 36. An opening 37, communicating with the bore 34, reveals the

contacts

13 and 14. A contact screw 38, occupying a threaded bore in the bushing 36, carries the contact 14 which in turn is aflixed' to a' spring'38 in a bore of the screw 38. The spring is held in place by a plug 39 through which the connection of the wire 31 tothetin strip contact is made. The insulating bushing or pin 36 has kerfs at quarters. (see Fig. 5) so 5m upon screwing the pin down into the bushing 32, the adjustment of the contact screw 38 becomes fixed.

The can top contact 41 consits of a piece of metal bent into L-shape and having the lowermost edge (Fi s. 8 and 9) sharpened so as to cut throng the enamel or other covering on the can top and complete an electrical circuit, in the event that one or more of such can tops ride on top of others and thus clog the chute 7 The electrical circuit mentioned, may be traced in Figure 1: Gurrent flows from the source G over wire 19, junction ring 21 and wire 27.to the second junction ring 29, out at the binding post 42, over Wire 43 to the knife edge contact 41, through the metal of the can top to ground at the frame of the press, thence returning to the source Gr via wire 18.

The completion of this circuit again results in short circuiting the electro-magnets 15 so that the latter lose strength and are comelled to release the lever 16 so that the press is stopped. The connection of the wire 43 is made directly to the contact 41 as shown in Figure 8. This contact is supported by a bracket 44, and the latter in turn by the side of the chute 7. A block of insulation 45 separates the contact from the bracket.

Although the description immediately following has no direct bearing on the invention itself, it may not be out of place to say that the can tops from the chute 7 are discharged into the semi-circularwthroat 46 wherein the edges are curled by'comin in contact with the groove-edged curler-w eel 47. The can'tops sometimes clognat the mouth of the throat 46 before being engaged by the curler wheel 47, and under such cir-.

cumstances, it :is necessary to stop the press. This is accomplished through the function of the knife-edge contact 41 and in the manner just disclosed i The scrap-chute contact 48 is much on the order of the contact/41- just described, the exception/being :that the knife edge of the latter is now mitted, and thecontact is turned up instead of down. =/Ihe :contact 48 has a beveled approach 49. It is mounted beneath the scrap chute- 8 *(seeFig; 10) aninsulating block lroweverriintervening. It is only'whenthe chuteii8'abecomes clogged by an accumuiationwofvscra'p. =t1n, that the contact 48 functions-21m :stopithe press, this being accomplished by: short .cir cuiting the electro-magnets 15, current flowing along 'thefollowing patli:;-,-Erom.- the source Gover wire l9 to 'theiijunction ring 21, out at the binding post 51, ovenwire 52, to the contact 48, returning tozthei negative pole'of the source ofenergy-Wia thegronnd connection 'and wire"* 18.-* As? before, the elcctro-magnets 15 areshort circuited, caus: ing the release of the leveril61and -the consequent stopping ofthe press. 5 4 The lever-.16 has a connection 53 which-extends to: the means (not-shown) by which: the press is stopped.

The edge or the contact 48-(Fig. 10) does not reach high enough to make contact with the scrap so long as it lays flat in the trough above it, and does not .become jammed. But the scrap is so light from having ends cut out of it, that if it happens to catch in the chute it wads up so that the impeller 9 (Fig 2) pushes the scrap down against the contact edge 48. The normal function of the impeller is to kick the scrap out of the chute.

It sometimes happens that the scrap chute is not adjusted properly, permitting the scrap to get underneath the chute. In such event, it strikes the beveled approach 49 which, again, short circuits the current and stops the press. It may also happen that the stripper-ring on the punch of the press may push jammed scrap against the contact. In any event, the tendency of the scrap to jam in the chute soon causes a suflicicnt piling or doubling up of the scrap between the two pieces of angle iron of which the chute is composed, thereupon making contact with the member 48 and performing the function mentioned.

The bearing bracket 54 (Fig' 1) supports the outer end of the starting lever shaft 55 (Fig. 14) the reduced end of which moves freely in it. It is important that the stopping lever 16 should have very little friction at the moment when it is disengaged from the magnet 15. To further this purpose, the frame 1 has an aperture at the right side madesufliciently large to avoid contact with the starting-lever shaft 55. The left reduced endof the shaft 55 has bearing in the left side of the frame. The lever 16 is fixed on the shaft The bracket 54-is. secured by means of a screw 56 and dowels 57. It is desirable that the starting' rlever shaft should be loose enough in its bearing to allow a rolling motion and thereby vfacilitate the movement .of the leverupondeenergization of the magnet.

-.Both electric 'unction blocks are alike in construction. ne is shown in detail in Figure The junction ring 21 (mentioned before) issecured on. the thick insulating washer 58 by the four binding screws. "This washer is fitted-against a larger but thinner insulatingwasher59, all being held in place on-the side of the frame bv the central Screw 60.

-Whilethe construction and arrangement of the improved automatic stop motion mechanism as herein described and claimed, is that of a enerally'preferred form, obviously modi 'ations and changes may be made without departing from the spirit of the invention or the scope of the claims.

Iclaim:.- -lHStopLmotion mechanism, including a starting-and stopping lever, and electromagnetic means energized to hold the lever in the starting position with a predetermined force, to withstand vibrations of a strength equal to said force but not those in excess thereof.

2. Stop motion mechanism. comprising a starting and stopping lever subject to vibrations, electromagnetic means for holding the lever in the starting position, and an electrical circuit for energizing said means to produce a holding force of a predetermined strength on the lever to counteract vibrations of equal force but not those in excess thereof.

3. Stop motion mechanism, comprising a starting and stopping lever subject to vibration, electro-magnetic means for holding the lever in the starting position, and a closed electrical circuit furnishing current to said means to hold the lever during vibrations of a strength equal to that of said means, but not in excess thereof.

4. Stop motion mechanism, comprising a starting and stopping lever subject to vibration, electromagnetic means for holding the lever in the starting position, a closed electrical circuit furnishing current to said means to hold the lever during vibra tions of a strength equal to that of said means, but not in excess thereof, and associated means for short-circuiting said electromagnetic means to weaken the hold of the latter for the release of the lever.

5. In combination with a machine causing vibration in operation, a lever for starting and stopping the machine, and means to which the lever adheres in the starting posi tion during vibrations of a predetermined normal strength but which is overcome by vibrations exceeding said strength to drop the lever to the stopping position. 7

6. In combination with a machine causing vibration in operation, a lever by which the machine is started and stopped, an electro-magnet in a circuit which remains closed to continuously energize the magnet at a certain strength to hold the lever in the starting position during normal vibrations which if exceeded jarsthe lever loose, and electrical contact means distributed among a plurality of locations throughout the machine, closable by a malfunctioning of machine parts at such locations to short circuit the electro-magnet for the weakening thereof and the release of the lever.

7. In combination with an automatic press including sheet feed mechanism, a die, a chute for the product, a scrap chute and a lever for starting andstopping the press; an electro-magnet continuously ener 'zed at a predetermined strength to hold the liver in the running position but being adapted to be jarred loose by vibrations exceeding the strength of the magnet when the sheet sticks on the die, and electrical contact means closable to short circuit and weaken the electromagnet for the dropping of the lever and stopping of the press, upon the feeding in of an extra thick sheet, or the clogging of the product chute or the clogging of the scrap chute respectively.

8. The method of automatically stopping a press, consisting of jarring its starting and stopping lever loose from an energized electromagnet while in a running position by vibrations caused by the press and exceeding the strength of the electromagnet.

9. The method of automatically stopping a press, consisting of holding its starting and stopping lever in a running position by a predetermined force, jarring the lever loose to fall to the stopping position, by vibrations of a strength exceeding said force and caused by the operation otthe press; and diminishing said force for the release of the lever through instrumentalities becoming active upon the mail-functioning of parts of the press.

10. In an automatic strip feed press. a starting and stopping lever, continuously energized electro-magnetic means for holding the lever in the running position, and a contact associated with the feed mechanism and in shunt circuit with said electro-magnetic means, including a stem moved to close a circuit by a strip of extra thickness, and thus short-circuit the electro-magnetic means for the release of the lever.

11. In an automatic strip feed press including a starting and stopping lever, continuously energized electro-magnetic means for holding the lever in the running position, and contact means associated with the feed prom mechanism and in shunt circuit with said electro-magnetic means, including a relatively fixed contact point and a relatively movable'contact point pressed into engagement with the relatively fixed contact point by the admission of a strip of extra thicknew to close the associated circuit and short circuit the electromagnetic means for the release of the lever.

121111 an automatic strip feed press including a starting and stopping lever, and a discharge chute; a closed circuit embracing and continuously energizing electro-magnetic means for holding the lever in the running position, and insulated contact means in the chute, closing a circuit when the latter becomes clogged to short-circuit the electro-magnetie means and cause the release of the lever. V

LYMAN LLEWELLYN JONES.