US2438712A - Fastener-applying implement - Google Patents

Description

March 30, 1948. c. M. LINDSTROM FASTENER-APPLYING IMPLEMENT Original Filed March 29, 1945 2 Sheets-Sheet 1 Charles March 30, 1948. c. M. LINDSTROM 2,438,712

- FASTENER-APPLYING IMPLEMENT Original Filed March 29, 1945 2 Sheets-Sheet 2 fiwen 110k.-

I 0/2 arlesAZLjndsZrom Ifatented Mar. 30, 1948 to Boston'Wire Stitcher 'Comp a1iy', S't6il-ln'g'ton, 1 a car enter of i Ori ina appli atio a h" 435 No- -1 This invention relates to improvements in fastener-applying implements and the present application is a division of my prior application for United States Letters'Patent Serial No. 8 5,;- 486, filed March 29, 1945.

. fastener-applying means as elevated in position One object of the present invention is to provide an implement of the type indicated comprising improved fastener-feeding and driving means for preventing the driving of a s cond fastener before the first one has been discharged from the implement.

Another object is to provide an implement of the type indicated having a magazine in which the fasteners are fed forwardly and the fore most one in the series first carried" down onto} rest in reserve position before it is applied to the work at the next operationof the fas ener-as;

plying means.

Another object is to provide an implement for applying fasteners of a type having crowned heads or crossbars by first flattening their heads and thereafter driving them into the work and clinching their legs on the underside thereof with close contact of the'parts of theffas'tene'rs against the work.

Another object is to provide an implement of the type indicated in which the crowned head or crossbar of the fastener is flattened by the driver as the fastener is carried down into reserve po sition on a rest and the legs of the fastener are spread apart so that the ends of the crossbar underlie hold-down or retaining means to prevent the fastener from rising up.

Further objects of the improvement are set forth in the following specification which describes'a preferred form of construction of the invention, by way of example, as illustrated by the accompanying drawings. In the' drawings:

Fig. '1 is a sectional view ofthe implement taken in a vertical plane coincident with its longitudinal axis and showing the operating parts within its interior;

Fig. 2 is a plan view of the implement with the fastener applying arm shown in transverse section to illustrate the parts enclosed therein;

Fig. 3 is an enlarged transverse part-sectional view of the forward part of the implement taken on line 33 of Fig. 1; H

Fig. 4 is a similarly enlarged longitudinal sectional view of the forepart of the implement showing the parts in the same position as in Fig. 3;

Fig. 5 is an enlarged sectional View similar to Fig. 3 but showing the parts of the implement in position with the fastener-applying means depressed toward the clinching means;

Fig. 6 is an enlarged longitudinal sectional view of the forepart of the implement showing its operating parts in the same position as in Fig. 5;

Fi '7 is a View similar to Fig. 3 showing: the

test prior to driving a staple into the work; Fig. si'sfa longi'tudinalsectional view of the iorepaft of the implement showing the partsi n th'esiame position as in Fig.7; 7 19 isa det iled view illustrating the relations'hip between the fastener and its driving meansjust prior to flattening its crowned eross bar; and Fig. 10 shows the driving meansdepressed to straightener flatten the crossbar of a fastener whilesp'reading its legs to position the. fastener beneath the hold-down means. H The present improvements are shown in substantially the same form as in my prior applica tion fiohi which this application is divided and only such parts as are necessary to an unders"tanclirig of the fastener-applying means will be described in'detail herein; In general, theimplementcompr'ises'a magazine Zin the form of a trough-shaped arm, a fastener applying arml pivotallyeoniiected to the magazine arm in. overlying relation theretofa clinching arm tunderlying the'magaz'ine-arm and pivoted thereto; and a manually-operable force-multiplying"lever; 5 connected to' actuate i the fastener-applying ineans andclincher-arm. The magazine 2 is oi channel-shape in crosssectioncornprising a bottom'wall B and parallel sidewalls 9 extending upwardly therefrom: as shown" in Figsfl, 2 and'3; l The forward ends. of theside walls 9 of the magazine projectbeyond its bottom wall 8 and are'iolded inwardlyi in flange-like portions llljsee Figs; 1 and'2'. I Atthe forward end oi the' inaga'zine 2' the side walls 9 are extended upwardly in'wing-iike portions I-2 formed with outwardly-projecting ears l3"bent top of'thes'ide walls folded inwardly toward each other. In the present form of construction of theimplemen't the side flanges l8 arev relatively narrow throughout the greater portion ofthe length of the core 15, but adjacentthe forward end they are extended in opposite angular relationship to' meetsubstantially at the center, see dottedlines in Fig; 3, in rectangularly shape'd portions'or tabs'2fi". These meeting 'portion'szor tabs 26 are inclined upwardly toward; the. center of. the core to provide'a beveled rest for staples s having" crowned heads or crossbars .In. other 3 cases the rest formed by the tab portions 20 may take different shapes, for example, they may 3 arm 3 is widened transversely by offset portions have a curved contour for an arcuate form of the flanges l at the front of the magazine-arm 2 to provide vertical guide-ways or grooves 2| adapted to receive a slidable staple-driver 25, to be described later. overlying the top of the core -|5 at its forward end in spaced relation to the tabs 20 31 of its side walls 34 while the forepart of the arm narrows again in conformity with its rear- I ward portion. Along its rearward portion the side walls 34 of the'arm 3 are joined together by a top wall 38, but forwardly thereof throughout its widened and front portions the top wall is cut away with an extended opening 40 to provide a window or doorway for inserting staples therethrough into the magazine-arm 2. Adjacent the forward endof the arm 3 its side walls are staked is a substantially U-shaped guard-member 22 having its sides welded or otherwise suitablysecured to the upstanding wing-like portions l2 on the sides 9 of the magazine-arm 2. The forward edgesof the sides of the member 22 are spaced rearwardly from the flanges It] on the arm 2 to form a continuation of the grooves 2| for slidably mounting the staple-driver 25. The bottom transverse portion 23 of the guard member 22 is crowned or shaped to correspond with that of the tabs 25 to conform to the crowned crossbars of the staples as they rest on the tabs.

, Referring particularly to the enlarged Views, Figs/l, 6 and 8, it is to be noted that the staplerest comprising the tabs 20 is offset rearwardly from the forward edges of the side walls I"! of the core l5 to form relatively narrow shoulders 24 disposed below the rest and at the rear of the grooves 2|. These shoulders 24 serve as detents or auxiliary'rests for supporting each staple as it is fed off from the forward end of the core I5, see Fig. 6, it being noted by reference to Fig. 8 that the transverse portion 23 of the guard 22 is cut back to provide an open space above the shoulders 24. Above the shoulders 24 the sides 9 of the arm 2 are sheared to form extruded portions or lugs 3| which project inwardly therefrom for a purpose explained hereinafter.

The staple-driver 25 is in'the form of a hardened metal blade of varying thickness from top to bottom and provided with relatively narrow guiding fins or runners 23 adapted to slide in the grooves 2| at the forward end of the magazinearm 2. The blade of the driver 25 tapers in thickness from the top toward the bottom throughout its central portion, see Fig. 1, and then is recessed rearwardly at its lower end. The

or punched to force the metal inwardly in a pair of substantially arcuate portions, shown in Fig. l, which form abutments 4| adapted to be engaged by the lower edges of the ears or lugs l3 which project from the sides of the arm 2 as shown in Fig. 3, whereof to limit the upward movement of said arm 3 with respect to the arm 2. Suitably secured to theinner faces of the widened portions of the sides 34 of thearm 3, as by welding or'riveting, are a pair of studs 45 having reduced central portions bounded by flanges as shown most clearly in Fig. 2. The studs 45 are engaged by the ends of the manually-operative lever 5 in lower recessed end of the driver 25 is thus formed with an olTset shoulder 28 raised slightly above its forward edge. Near this end of the driver 25 is a circular hole 21 for connecting it with the staple-applying arm 3. On its rearward face the upper portion of the driver 25 is thickened toprovide a substantially rectangular pad or projection 29 having its lower edge in the form of a horizontal shoulder 30 which overhangs the detentshoulders 24 at the forward end of the-core l5. The lower edge of the pad 29, that is the shoulder 30 formed thereby, is straight across the width of the driver, the purpose of this form of construction being to adapt it to engage with and flatten or straighten the crowns of the staples.

The staple-driver 25 is connected to be reciprocated by the arm 3, this connection comprising a stud 33 fastened in the forward end of the arm 3 and having its projecting portion engaging through the hole 27 near the lower end of the driver, see Fig. 1. The staple-applying arm 3 is of inverted channel shape in cross-section with its side walls 34 tapering slightly toward its rearward end which is formed with semicircular ears 35 pivotally connected to the sides of the magazine-arm 2 by means of a crosspin 36, see Figs. 1 1

and 2. Substantially midway of its length the a manner as later explained.

The clinching arm 4 is generally of channel shape in cross-section having its forward longitudinally-tapered portion offset below its main rearward portion, the sides of the latter being of greater depth. .At its rearward end the sides of the arm 4 overlap the sides of the magazine-arm 2 and are provided with holes for receiving the cross-pin 36, previously mentioned, to pivotally connect the arm 4 to the arms 2 and 3. Positioned within the forward end of thearm 4 and welded or otherwise suitably secured to the walls thereof is a hardened block 41 formed with clincher-grooves 48 of usual construction, see Figs. 1 and 5, which are in substantial alinement with the lower edge of the staple-driver 25.

The manually-operative lever 5 is of channel shape in cross section with its rearward portion formed with a rounded bottom wall providing a hand-grip and its forward side walls 49 extended upwardly at an angle to adapt them to straddle the sides of the clincher-arm 4. A crosspin 50, see Fig. 2, projects through holes in the sides of the arm 4 and the side walls of the lever 5 for pivotally mounting the latter on the arm. The upper ends of the side wal1s43 terminate in hooks 5| engaging around the studs 45 which project inwardly from the walls of the staple-applying arm 3, see Figs. 1 and 2, whereby to connect the lever 5 for rocking said arm downwardly to reciprocate the driver 25 across thee nd of the magazine-arm 2. Rearwardly of the hook portions 5| of the lever 5 the sides 49 are formed with cam-faces 52 which operate on the studs 45 with an increased pressure or mechanical advantage, see Fig. 1, during the completion of driving and clinchingthe staples. The clinching arm 4 is normallymaintainedin spaced relation to the magazine-arm 2 and the staple-applying arm 3 through the means of a leaf-spring 55 end of the spring 55 bears on the under side pin 50 to connect this end of the magazine-arm 2 and its forward end engages under the crosspin 5|] while its central bowed portion bears against the bottom 'wall of the arm '4. A tongue 56 formed by a portion of the metal slit fromthe end of the spring 55 is bent upwardly and curved around the top'of the of the spring therewith. a i

Referring particularly to Fig. 1 of the drawings,

their cross-bars and is slidable longitudinally of.

the magazine 2 to adapt it to'open' it for receiving the staples inserted through the window or door id in the top of the staple-applying arm 3. The cover 50 may be crowned along its central portion to adapt it to conform to the shape of conventionally-crowned staples and at its rearward end it is bent downwardly to form a tailpiece ti adapted to be gripped in the fingers to draw the cover rearwardly along the top of the magazine 2. The cover '60 is maintained in'position overlying the upper edges of the sides 9 of the magazine-arm 2 by means of a leaf-spring 63 bearing against the top wall of the stapleapplying arm 3. ward end of the spring fitbears against the under side ofthe top wall 38 of the arm 3,its middle bowed portion bears against the top of the cover 5, and its forward end. is fastened to the top wall 33 by a lug 6d of the metal slitted therefrom and bent downwardly to project through a hole 65 in the spring.

The staples s are advanced along the core l5 in the magazine-arm Z'by means of a staplepusher 68 of usual construction adapted to overlie and straddle the core. Referring to Figs. 1 and 2, the staple-pusher 66 is constructed of sheet-metal with a top wall 61 and downwardlybent flanges or side walls 68. The side walls 68 extend forwardly beyond the forward end of the top wall 8'! which is bent downwardly with a portion 69 therebetween as shown most clearly in Figs. 1 and 2. walls GB-are adapted to engage the legs of the rearmost staple in the magazine 2 to slide the while series forward on the core l5. The staplepusher 5 5' is slid forwardly along the core l5 under the tension of a helical spring l,'the forward end of which bears against the bent down portion 69 of its top wall 51. The rearward-end of the spring ll! encloses a hollow stud H and bears against its flanged end 12 to press it against the crosspin 36 which pivotally connects the arms 2, 3 and 4.

After the cover 6 has been withdrawn along the top of the magazine 2 and the pusher 66 has been retracted therein, the stick S of staples is inserted'through the opening 4!] in the arm 3 and placed in the magazine with the legs of the staples straddling the core l5. The cover 60 is then slid forwardly on the magazine 2 into the position illustrated in Fig. 1 where its forward end brings up against the guard member 22.

The cover 6 will thus serve to hold the staples from riding up on the core l5 and the implement is ready for operation.

To apply a staple to the'work the implement is grasped with the palm of the hand overlying the staple-applying arm 3 and the fingers pressing against the rounded under side of the operatlever 52. Then by applying pressure to the lever 5 its hooked connection with the studs 45 on the arm 3 will act to swing the latter and the clincher-arm l toward each other. During this relative movement between the arm 3 and arm 4 the leaf-spring 55 is compressed, but the spring 63 will resist relative movement between the arm J and the magazine-arm 2. When, however, the forward end of the magazine-arm is brought into contact with the work the arm 3 will continue its motion to compress the spring 63. The motion of the arm 3 relative to the magazine-arm 2 will cause the staple-driver 25 to be slid down- As shown in Fig. l the rear- The forward edges of the side 6 wardly in the grooves 2|". at. the forward; end of the magazine-arm. When the magazine is first'supplied' with staples s, that; is unless staples. already remain therein, the first action of the,

staple-driver 25: will be to separate a staple, s from thefstick and;carry it down onto the detentshoulders 24;

wardly projecting lugs 3| so that the lugs will prevent the'staple from rising to any considerable extent above the detent-shoulders 25.

The staple separated fromthe strip and moved into reserve position resting on the shoulders 24. beneath the lugs 31 thus willbe retained invthis.

position until the driver 25 is raised again by release of the pressure on the lever 5. As the rearward edge 28. of the driver 25. rises above the shoulders 24, see Figs. 7 andB, the staple s, resting on the shoulders 24 will be pushedoif,

therefrom by the legs of the next succeeding staple on the core 15 as the whole series of staples is advanced bythe pusher. 56, At the next descentof the staple-driver 25, as the implement,

is again operated, the, driver will engage the top of the staple. 5 advanced into position beneath its edge 28,to force it down into the grooves 2i and drive it through'the work as itslegs are bent inwardly by the curved clincher-grooves and clinched on the under side of the work. The purpose o-f this form of construction and arrangementof the parts is the same as that shown in U. 8., Letters Patent No. 2,420,830 granted to Arthur H. MaynardMay 20,. 1947', the present invention embodying simplification and improvement thereover. The objectof this arrangement is to prevent asecond staple being drivenbefore the first one has been. discharged from the machine or, in other words, to. avoid driving one staple on top of another which would be liable to clog the machine. It will be observed.

that ifithe driver25shlould be depressed insufiiciently'to complete the driving andclinchin of a staple, a second staple could not be entered into the grooves beneaththe driver until the latter has completed the application of the first staple, that is, the staple being driven and remaining in the grooves beneath the driver willprevent another staple being fed off from the detentshoulders 24.

The implement may be operated continuously in the manner explained above to apply staples to the work in multiple and usually a fresh supply is inserted in the magazine before all the staples have been exhausted therefrom.

It will be observed from the foregoing specifie cation that the present invention provides an extremely simple and compact form-of implement of the plier-type for applying fasteners while operating it in one hand. The structure and arrangement of the parts of the implement are considerably simplified and'improved over previously useddevices of thesame type to render the implement more economical to manufacture without loss of efficiency in its operation.

That is to say, as the driVerZB descends the shoulder 30. on. its rearward. face It is to be understood that while the present' improvements are shown as applied to'a pliertype of stapling implement they may be adapted for fastener-applying devices of other types and therefore the inventionis' not limited in respect to its particular use as herein shown. Likewise, various'modificatiosn may be made in the structure and arrangement of the parts of the implement, without departing from. the spirit or scope of the invention. Therefore, without limiting myself in this respect, I claim:

1. A fastener applying implement comprising a magazine for containing a supply of fasteners having crowned crlossbars, means to support the fasteners in the magazine, a rest for supporting a fastener below its normal position in the magazine at the forward end thereof to hold it in reserve position, fixed hold-down means engageable across the ends of a fastener on the rest to prevent it from rising up therefrom, a reciprocable driver slidable across the front of the magazine and having a portion engageable with a fastener to carry it down onto the rest, straighten its crowned crossbar and position the ends thereof beneath the hold-down means, and resilientlyoperated means for feeding the fasteners forwardly to position the foremost one beneath the driver and cause it to be forced down onto the rest, said feeding means operative thereafter to advance the reserve fastener into position to be driven into the work at a subsequent stroke the driver.

2. A fastener-applying implement comprising a magazine for containing a supply of U-shaped fasteners having crowned crossbars, a throat at the forward end of the magazine through which the fasteners may be driven to apply them to the work, a core in the magazine for supporting the fasteners in straddled relation thereon, a rest below the top of the core at the forward end of the magazine adapted to support a fastener in reserve position at the rear of the throat, holddown means projecting across the top of the rest at the sides thereof, a driver reciprocable in the throat of the magazine and formed with a straight edge overlying the rest at the front of the core, means for reciprocating the driver to cause its rearward edge to engage the foremost fastener in the magazine and force it down onto the rest while straightening its crossbar to cause its legs to be separated and the ends of its crossbar carried into position beneath the hold-down means, and means operative to advance the fasteners in the magazine to feed the reserve fastener off from the rest into the throat beneath the bottom of the driver to adapt it to be driven into the work. 7

3. In a fastener-applying implement, a channel-shaped magazine for containing a supply of fasteners, a throat at the end of the magazine through which the fasteners are driven, means for feeding the fasteners forwardly into the to flatten said crossbar and spread the legs of.

the staple into position beneath the hold-down means, and means operative to feed the fastener off from the detent-shoulderswhen the driver-is raised to'cause it tojbe engaged; by the bottom edge of the driver to drive'it'into the work.

4. Ina fastener-applying implement, amagazinefor containing-a-supply of fasteners having crowned tops", a core in the magazine adapted to support the fasteners in straddled relation there-. across, ,detent-shoulders offset "below' the forward end of the core anol adapted to support a fastener in reserveposition thereon, hold-down means for the fasteners above the detent-shoulders, a driver slidable across the front'of the magazine and having a portion of its rearward face formed with. a straight transverse shoulder adapted to engage a fastener advanced beyond the end of the core to carry it down onto the detent-shoulders, said shoulder on the driver acting to straighten the crowned top of a fastener to force its legs outwardly into position'beneath the holddown means, and means operative to feed-the straddled thereacross, detent-shoulders at the" forward end of the magazine below the top of the core to adapt them to receive a staple in reserve position, lugs projecting inwardly from the sides of the magazine above the detent-shoulders, a driver reciprocable in the throat of the magazine and having a rearwardly-projecting edge overlying the detent-shoulders at the front of the magazine, means for reciprocating the driver to cause its rearward edge toengage the foremost staple in the magazine to carry it down onto the detent-shoulders while compressing its crossbar to spread its legs into positionbeneath the lugs on the sides of the magazine, and'means opera- 7 tive to advance the staples in the magazine to feed the foremost staple off from the detentshoulders into position beneath the lower edge of the driver to adapt it to be driven 'into the work.

6. In a fastener-applying implement, a magazine for containinga supply of U-shaped staples having crowned Crossbars, a core in the magazine for supporting vthestaples in straddled relation thereon, detent-shoulders disposed below and in advance of the forward end of'the core to adapt them to support a staple in reserve position thereon, lugs projecting inwardly from the sides of the magazine above the detent-shoulders,

a throat in advance of the detent-shoulders through which the staples maybe driven, a driver slidable in said'throat and having a rearward portion formed with a transverse shoulder overlying the detent-shoulders at the end of the core, means for resiliently feeding the staples forward in the magazine, and means for reciprocating the driver to cause it to first carry a staple down onto the detent-shoulders and flatten its crown to spread its legs toward the sides of the magazine beneath the lugs thereon and to thereafter engage a staple fed off from the'detentshoulders to drive it downwardly in the throat and'into the work.

CHARLES M. LINDSTROM.

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