US2440479A - Stapling apparatus - Google Patents

Description

I April 27, 1948. I J. c. LANG 2,440,479

STAPLING APPARATUS Filed Nov. :50, 1942 '3 Sheets-Sheet 1 B" r I ZZFIF H L y W u INVENTOR April 27,- 1948.

, J. c. LANG STAPLING APPARATUS Filed Nov. 50, 1942 s Sheets -Sheet s .mw i

Patented Apr. 27, 1948 STAPLING APPARATUS Joseph C. Lang, Pittsburgh, Pa, assignor to Bocjl Corporation, a corporation of Delaware Application November 30, 1942, Serial No. 467,365

17 Claims.

This invention pertains to the art of staplin and is for an apparatus wherein the staple is of special form whereby it is reinforced against bending during driving and wherein it has an increased holding power over the conventional U-shaped staple, and is for a machine in which the staple is clinched while it is being driven without the use of any anvil under the work and without bending the legs of the staple after they have penetrated the material.

The invention is complementary to the invention disclosed in my copending application Serial No. 467,366 filed November 30, 1942, issued as U. S. Letters Patent No. 2,393,327 on Jan. 8, 1946, for Staple driving method and apparatus. Insofar as any subject matter of the present application is common to my said copending application the. broad subject matter is covered in the said copending application and the present application is directed primarily to an instrument for driving a specially formed staple according, however, to the general principle disclosed in the said copending application.

The present application also is a companion application to my copending application Serial No. 467,367 filed November 30, 1942, issued as U. S. Letters Patent No. 2,380,655, on July 31, 1945, for an improvement in staples and method of stapling, wherein the specific form of staple is separately claimed. I

In the latter application there is disclosed a staple having a crown which is longer than the spread between the legs of the staple. The staple has spaced parallel legs which are joined to the crown by an outwardly turned fold or lobe so that the lobes project outwardly beyond the legs of the staple. In the preferred form of staple the crown is depressed so that the undersurface of the crown occupies the same plane as the undersurface of the lobes of the staple. This form of and as the staple progressively moves through the kerfs the succeeding portions of the legs are bent so that the legs of the staple enter the material on a curved path and this curvature is followed throughout the driving of the staple. When the staple has been completely driven it will beclinched. For use with such an operation a specially formed staple of the type referred to presents a further difilculty in that the legs of the staple must be very accurately guided into the kerfs in order for the machine to function properly.

It is a purpose of the present invention to pro vide a driver for specially formed staples of the type referred to in which means is provided for guiding the legs of the staple, such means being moved out of the way when the staple has been completely driven. This means assures the legs of the staple properly entering the kerfs in the masking means and it also supports the legs against buckling during the driving operation. The invention further provides means for applying a desired amount of friction to the staple to prevent it from dropping freely when it enters I the staple guide so that it is pushed down by the staple has certain advantages which are clearly pointed out in the said copending application. While it has certain advantages it also presents a problem from the standpoint of driving it. The conventional U-shaped staple, when it enters the staple guide, fits into the guide, the legs being received in the staple guide which hold the staple so that it can not tilt. The legs can not how outwardly during the driving of the staple because of their engagement with the Walls of the staple guide. However, when the staple is modified to the shape shown in the latter of the .two above mentioned applications, only the lobes or ears on the staple engage in the staple guides and the legs of the staple have no lateral support to predriver instead of falling clear of the end of the driver. The present invention also provides a masking means for cooperation with the specially formed staple. The invention also provides certain other improvements, particularly in the manner of supporting the staples in the magazine prior to being driven. My invention may be readily understood by reference to the'accompanying drawings, in which:

Figure 1 is a side elevation of a complete machine for closing boxes, the machine being constructed in accordance with the present invention;

Figure 2 is a longitudinal section on a larger scale than Figure 1, showing the staple feeding and driving mechanism;

Figure 3 is a fragmentary transverse section in the plane of line III-III of Figure 2;

the slots 31 tends to cam the strips 36 inwardly or toward the right as they are pulled outwardly. However, the-strips 36 can move downwardly and outwardly. The strips 36 in conjunction with the shoulders Illb provide the grooves designated 46 in Figure 8 that constitute the lower portion of the staple guide or chute. The strips 36, as best shown in FiguresZ and 5, form an abutment against which the endmost staple at the left of the mechanism engages to limit the movement of the staples toward the left. When the staple is projected forwardly so that its lugs or lobes contact the strips 36, the staple will, be

directly under the driver. While the lugs or lobes of the staples will be guided in the slots 46 the legs of the staple will also be engaged in the grooves 49 but the legs will be spaced inwardly from the side plates. This is best seen in Figure 4 where the staple is shown in dotted lines and where it will be seen that the legs of the staple are guided by the strips 36 but that the legs arespaced inwardly from and unsupported by the side plates I9.

The strips 36, being urged inwardly to a limited extent by the cam slots 3'! and springs 39, exert a yielding frictional pressure against the staple so that it cannot fall freely down the staple guide but is frictionally held in the staple guide until the staple is actually forced downwardly by the driver.

The foregoing arrangement in which the strips 36 are used to exert pressure against the staple is a novel arrangement and is superior to mechanisms heretofore provided for frictionally engaging the staple to prevent it from dropping freely.

Pivoted to the exterior of each side plate IS on a pivot pin 4| is a bell crank 42 having a downwardly extending arm 43 and a horizontally extending arm 44. A tension spring 45 has one end attached to the arm 44 and the other end anchored at 46 to the side plate 19. The downwardly extending-arm 43 is turned inwardly at 43a and passes through a hole 41 in the side plate. Inside of this plate it extends downwardly and forwardly as indicated at 48, the terminal portion 48 being in the shape of a hoof and the hoof portion of each arm 43 projects across the staple guide. As best seen in Figure 4, this hoof is bifurcated, as indicated at 49, so that the legs of the staple, as the staple is pushed down the guide, pass through the bifurcated ortion 49 of the hoofs. These hoofs serve as guides to direct the points of the staple into kerfs 56 formed in the masking plate or guide plate 5| slidably carried on the bottom of the staple driving unit and which will be hereinafter more fully described. The forwardly and downwardly inclined surface of each hoof is engaged by the crown of the staple during the downward travel of the staple, thereby camming the hoof back out of the way of the crown or bridge of the staple. Figure 5 shows the terminal or hoof 46 in its normal position, and Figure 6 shows the hoof cammed back out of the way of the crown of the staple. The spring 45, acting through the bell crank lever, serves to return the hoofs or terminals 48 to their normal position after the staple has been driven and the driver has been retracted. These hoofs or slotted terminals of the bell crank lever are important factors in guiding the specially formed staples to assure the points of the staples being directed into the slots or kerfs 56 and are also important in preventing the legs of the staple from buckling either inwardly or outward- 1y during the driving of the staple. Their significance as a lateral support for the legs is best illustrated in Figure 7 4.

The stapling guide or masking plate 5| which effects the bending or clinching of the legs of the staple comprises a relatively thin, fiat part 5| at the bottom of the driving assembly. It has upwardly extending flanges 52 at each side thereof, these flanges embracing the lower edges of the side plates l9. Projecting out from the sides of the plates l9 are retaining pins 53, the pro- ,iecting ends of which are engaged in bayonet slots 54 in the flanges 52. This arrangement enables the plate 5| to be moved back and forth the length of the slots and it also permits the member 5|-52 to be removed should this be necessary for any purpose. The masking member 5| is resiliently urged toward the left as viewed in Figures 2 and 5 by means of a light metal strip 55 which is slidablyretained on the outer face of each plate l9 rearwardly of the member 5|. A tension spring 56 anchored to the plate at 5'1 and anchored to a stationary post 58 urges the plate 55 toward the left as viewed in Figure 5 to press against the end of the flange 52. When the plate 5| moves toward the right as viewed in Figure 5 it does so against the tension of the spring 56.

The plate 55 has a forwardly extending tongue portion 5| and it is into this tongue portion that the kerfs 56 are out. As explained in my copending application Serial No. 467,366 filed No vember 30, 1942, issued as U, S. Letters Patent No. 2,392,327 on January 8, 1946 these kerfs are cut at a curvature such that the tops of the kerfs are separated a distance equal to the spread of the staple and the tops of the kerfs are also in the plane of the diameter of a circle Whose diameter is equal to the spread of the staples. The kerfs 56 are of a width equal to the thickness of the legs. As explained in my copending application, the kerfs may be either curved inwardly or outwardly, but in either case the curvature is substantially a portion of the arc of the circle. In

. Figure 4 the kerfs are curved inwardly and it will be seen that as the staple is forced down the legs of the staple are progressively curved in passing through the kerfs, causing the points to penetrate and travel through the material in a curved path. 011 the tongue 5| betweeen the two kerfs is an upwardly and rearwardly eX- tending inclined tongue or cam 59 which, as shown Figure 4, has a width less than the distance between the two hoofs 49. As shown in Figure 5 this tongue 59 is in the path of the downward movement of the driver 22 and also in the path of movement of the crown of a staple being forced down the guideway by the driver. As the driving of the staple nears completion the crown of the staple engaging the cam 59 exerts a horizontal component of force, tendin to move the masking or guide plate 5| toward the right as viewed in Figure 5. Consequently, by the time that the crown of the staple is down to theplane of the top of the tongue 5| the plate 5| has been cammed back to a point where the staple is clear of the part 5| and is no longer within the kerfs. This enables the crown of the staple to be forced down tightly against the work into which the staple is driven. Referring to Figure 5, the tongue 5| is in its normal position. Figure 6 shows the position of the tongue 5| at the time the staple has :been partly driven and the plate 5| starts to move back, and Figure 7 shows the driver all the way down withthe tongue 5| reamen-7.9.:

The operation of the machine maynow Ice-d8 scribed. Assuming the magazine to havebeen chargedwith a row of stapleatheendmost staple on the left asshown in Figure 2 is'under the riverazz. Its-further movement toward-the left is blocked by the guide strips 36. treadle is depressed the driving'un-it as a whole is lowered against the surface of-= the box B. When the slideplate Eil contacts the surface of the' box further downward movement of thestapling machine as an. entire unit isarrested; In orderto prevent undue pressure on the surface of. the box, thereis an adjustable screw 68' on the bracketzawhich forms an abutment to limit the downward movement ofthe lower arm assembly of-the machine, this bolt contacting w-ith;the undersu-rface of the bar it. Continued down.-

ward movement of the treadle, however, thencausesthe driver 22 to move relatively to the lower part of the assembly and the driver-engages the staple which is in the guide and forces it. downwardly. The staple is retarded from fallingby the frictionexerted through the two guide strips 36; through the bifurcated swinging guides or hooflike. guides "58 and by these guides they are accurately alined with the kerfs 50 in the tongue of: the guide plate. With the continued downward movement of the staple the legs are forced through the kerfs 5b, as best shown in Figure 4; and thisdirects the points of the staples into the. material in a curved path. As the legs of the staple continue to move-downwardly successive 'portions of the-staple are engaged and curved so that the legs, instead of travelingin a vertical path, travel in the arc of a circle. This is-fullyexplained in my copending application Serial No. 467,366 filed November 30, 1942, issued as. U. S. Letters Patent N 0. 2,392,327 on January 8, 1946; When the staple has been partially driven into the material the crown of the staple will engage the inclined surface of the swinging guides or hoofs 48 and force them backout of the way to the position shown in Figure 6. With continued downward movement the crown of the staplewill engage the inclined surface 59 on the guide plate fil'so as to earn the guide plate 5| toward the right as viewed in Figures-5 and 6. When the crown of the staple reaches the level of the top. of the tongue hi the tongue 5i will be entirely clear of the staple and the driver will press the staplehome against the top flap or lift of the box as illustrated. in either Figures 9 or 10. In Figure 9 the staple, designated 6|, has the crown 62-flush against the top lift B of the box while the'curved legs 63 areclinched in the lower lift B of the box. In Figure 9 the legs are curved inwardly so that in clinching they meet and overlap. In Figure 10, in which corresponding reference numerals have been used, the kerfs are curved in so as to deflect the legsoutwardly. This increases the spread over which the holding powerof the staple is exerted. Either the type of clinching shown'in Figure9 or FigurelO may be. used. Because of the special form of-thei When the The legs ofthe staple first pass' staple the. downward'force of thedriver iSBXEItEdr against the crown squarel over :the tops ofwthew legsv of: the stapleand'in. line with the. legs-. This:

enables the staple to bev driven intoveryadense: 7 material such ashard fiber boardiandatoasatislegs from buckling in the initial-part of thedrive; These hoofs or: guides da'compensatefor th'ea'be sence'of the lateral support which the-sidewalls: of the staple guide provide for-theconventional U-shaped' staple. As above indi-cated this specialform of staple can be more satisfactorily drivenintohardmaterialdue to the legsbeing set.-in-:

wardly fromtheguides because, the pressurevisr appliedubyith'e driver to. the staple: directly-over; the legs and the lobes cfthe staple :form-awreinforcement to make the staple stronger than the conventional u shaped staple.- Also, 7 as' explained inmyicopending application Serial-'No.

467,367 filed NovembenBO, 1942 issued --as U;- S.

Letters Patent No; 2,380.;655,;on'July;3l-,. 1945 :the special' form. of: staple has anaddedii. holding.

power over the conventional U.-shaped .staple. Another important function of the guides or hoofsi.

Mis-theguiding'of thetlegs of 'the'staple intothe lierfs 50.

In the'present. application; thezguiding plate 51:. is carnmed back by thedownward movemen't of the staple but it will'be understoodthat this risc only one way of retracting the guide plate antl, if desired, the linkage system disclosed -in-my=copending application Serial No; 467,366fild-N6- vember 30,1942i'issued as U. E3.- Let-tersPatentNo.

2,392,327 onJan'; 8,- 1946; may be used "or-that any other appropriate mechanism may; be employedforthis purpose;

Since the driver is designeddfor use with a. specially fornied staple it' would not operate if" the conventional U -shaped Jstaple were" inserted in the magazine. In order topreventauserfrom] jamming the machine by attempting, to use staples other than theories particularly. intended" for it, the. magazine is designed to 'supportithe staples by suspending them from the lobes rather than the usual construction .of resting the crowns of the-staples on a baralong. which thestaples slide. There wouldbe no way, of supporting.con-v ventional staplesin the machine and therefore the. operator could not jam the machin by. at-

tempting. to. use staples, which. COlllClxl'lOt. be

handled by the driving mechanism. Also, as best seen in Figures Zand 3,. metal strips-19 are usecured to" the inner faces of: plates. to, and. the lower edges of these plates engagethestaples: S to aid in keeping them in. place, and these strips would prevent the use-of staplesinithe magazine:

in: which the crown between the: lobes is-v not inner surface of this-bifurcated terminal-guides:

one: edge of 'the' leg, that passes therethrough :and.

9 the other edge is engaged by the movable guide strips 36.

I claim:

1. A stapling machine of the class described having a reciprocable driver, means forming a delivery chute along which the driver is movable, guide means normally projecting into the delivery chute extending across the path of the driver and having slots therein positioned to engage and support the legs of the staple moving along the chute, said guide means being movable out of staple-engaging position.

2. A stapling machine of the class described having a reciprocable driver, means forming a delivery chute along which the driver is movable, guide means normally projecting into the delivery chute extending across the path of the driver and having slots therein positioned to engage and support the legs of the staple moving along the chute, said guide means being movable out of staple-engaging position, said guide means having cam surfaces thereon to be engaged by the crown of a staple being driven for moving the guide means clear of the staple.

3. A stapling machine of the class described having a reciprocable driver, means forming delivery chute along which the driver is movable, guide means projecting into the delivery chute normally extending across the path of the driver and having slots therein through which the legs of a staple moving down the chute will pass, means resiliently urging the guide means into normal position, and a surface on the guide means for engagement by the staple being driven or the driver by means of which the guide means is moved clear of the staple after the staple has been partially driven.

i. A stapling machine of the class described having means providing a staple delivery chute, a driver for moving the staples along the chute and forcing them into the material into which the staple is to be driven, and guide means normally extending into the chute in the path of movement of the staple, said guide means having open-ended slots therein the width substantially equal to the width of the staple being driven and through which the legs of the staple pass in beingdriven, said slots supporting the inner and outer faces of the legs of the staple, and means for retracting the guide means after the staple has been partially driven.

5. A stapling machine for driving staples of the type wherein the crown projects at each end beyond the legs of the staple, said machine comprising a driver, a guide chute along which the staples are moved by the driver and in which the ends of the crown of the staple being driven is guided, and movable guide means spaced inwardly from the sides of the chute for engaging and supporting the inner and outer surfaces of the legs of the staple while they are passing down said chute, said guide means being movable through the operation of the driving of the staple to a position clear of the legs.

6. A stapling machine for driving staples of the type wherein the crown projects at each end beyond the legs of the staple, said machine comprising a driver, a guide chute along which the staples are moved by the driver and in which the ends of the crown of the staple being driven is guided, and movable guide means spaced inwardly from the sides of the chute for engaging and supporting the inner and outer surfaces of the legs of the staple While they are passing down said chute, said guide means being movable through the operation of the driving of thestaple to a position clear of the legs, said guide means having cam surfaces thereon by means of which said means are engaged by the crown of a staple being driven and forced out of engagement with the staple after the staple has traveled a predetermined distance along the guide chute.

7. A stapling machine of the class described having a movable driver, means forming a staple cam surfaces which are engaged by the crown of the staple being driven for moving the said terminal portions clear of the legs of the staple, and resilient means for urging the levers to normal position after the terminals thereof have been displaced.

8. A stapling machine of the class described having a, reciprocable driver, means forming a delivery chute along which the driver is movable, guide means normally projecting into the delivery chute extending across the path of the driver and having slots therein to engage and support the legs of the staple moving along the chute, said guide means being movable out of stapleengaging position, there being stripsfiiiirming a portion of the guide chute at each side thereof, said strips being diagonally movable with respect to the face of the driver; and means for resiliently urging the strips upwardly and inwardly toward the driver for frictionally exerting pressure against staples in the chute.

9. A stapling machine of the class described having a driver, a supporting structure on which the driver is movable, means on the supporting structure providing a staple delivery chute along which the driver moves, masking means on the supporting structure movable in a, plane at right angles to the direction in which a staple moves and being driven, said masking means having open-ended slots therein positioned to receive the legs of the staple being driven, said slots being curved in the direction of travel of the staple for bending the legs, means for withdrawing the masking means from engagement with the staple after the staple has been partially driven, and a staple guiding means in the chute above the masking means having straight slots therein for supporting the inner and outer faces of the legs of the staple passing down the chute, said guiding means also being movable out of staple engaging position.

10. A stapling machine of the class described comprising a supporting structure, a reciprocable driver on the supporting structure, means in the supporting structure providing a chute along which staples being driven are moved by the driver, means for delivering staples to the chute,

masking means on the bottom of the supporting structure at the end of the staple delivery chute having slots therein normally positioned to receive the free end of the legs of the staple as the staple is being driven, said slots being curved to bend the legs of the staple as the staple passes through the masking means, means for withdrawing the masking means from engagement with the staple after the staple has been driven 11 to,a predetermined extent, and guide means normally projecting intothe chute across the path of travel ofthe driver and having guide slots therein for guiding the legs of the staple into the slots in the mask and for supporting the inner and outer faces of the staple against buckling, said guide means being movable to a position clear'of the staple.

11. A stapling machine of the class described comprising a supporting structure, a reciprocable driver on the supporting structure, means in the supporting structure providing a chute along which staples being driven are moved'by the driver, means for delivering staples to the chute, masking means on the bottomof the supporting structure at the end of the staple delivery chute having slots therein normally positioned to receive the free end of the legs of the staple as the staple is being driven, sai'd slots being curved, to bend the legs of the staple as the staple passes through the masking means, means for withdrawing the masking means from engagement with the staple after the staple has been driven to a predetermined extent, andguide means normally projecting into the chute across the path of travel of the driver and having guide slots therein for guiding the legs of the staple into the slots in the mask and for supporting the inner and outer faces of the staple against buckling, said guide means being movable to a position clear of the staple, the guiding means having cam surfaces thereon positioned to be, engaged by the crown of a staple being driven for moving the guide means out of engagement-with the stapleas the crown moves down the chute.

12. The combination in a stapling machine of the class described having a staple chute and driver, of bifurcated means for engaging and guiding the inner and outer faces and one edge of the legs of a staple moving down said chute,

said means being movable from a position to engage and guide the staple to aposition clear,

thereof.

13. The combination in a stapling machineof the class described having a staple chuteandv driver, of bifurcated means for engaging and guiding the inner and outer faces and one edge, of the legs of a staple moving down said chute:

said means being arcuately movable from a DQSL tion to engage and guide the staple to a position clear thereof.

driver, of bifurcated mean for engaging and guiding the inner and outer faces and one edge of the legs of a staple moving down said chute,

said means being movable from a position to en- 1'2 gage and guide the staple to a po ition clear thereof, and means yieldably pressing againstthe other edges of said staple. 15. A fastener-applying implement comprising means for driving U-shaped staples into the Work, a retractable deflector-element mounted on into the work, and means operable by the driving of a staple to retract the deflector-element out,

' of range of the driving means.

17. A fastener-applying implement comprising means for driving U-shaped staples into the work, a yieldable deflector-element mounted on the implement and provided with means engageable With the legs of a staple to deflect them inwardly toward each other as they are driven into the work, and means integrally formed on said deflector-element and operable by the drivingof, a staple to yieldably move the deflector-element out of range of the driving means.

JOSEPH "C. LANG.

REFERENCES omeo The following references'are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 66,968 Kendig July 23,1867 249,851 McGill Nov, 22,1881 275,435 Sweet 1 Apr. 10,1883 313,948 Mower Mar, 17,1885 438,399 Bradley et al. Oct. 14,1890 987,024 Sturtevant Max: 14, 1911; 1,309,731 Hawkins 1 July 15, 1919. 1,586,064- Briggs May 25, 1926; 1,865,597 Svvitzeny July5, 1932; 1,907,849 Maynard May'9, 1933, 1,983,398 Polzer Dec 4,- 1936: 2,150,332- Maynard Mar l4, 1939 2,161,449 Blumenbaum Juned, 1939 2,181,387 Weber 1 Nov-.-28;,1939 2,238,736 Humphreys Apr, 15, 1941 2,268,102 Attula Dec.-30, 1941 2,298,123 Harred Oct. 6,l942;

Certificate of Correction Patent No. 2,440,479. April 27, 1948. JOSEPH O. LANG It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Column 1, line 14, for the patent number 2,393,327 read 2,392,327; column 12, line 51, list of references cited, under the heading UNITED STATES PATENTS for the date Dec. 4, 1936 read Dec. 4, 1934; andthat the said Letters Patent should be read with these corrections therein that the same may conform to the record of the casein the Patent Oflice.

Signed and sealed this 15th day of June, A. D. 1948.

' THOMAS F. MURPHY,

Assistant Oommissibner of Patents.

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