US 2954561 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Oct. 4, 1960 H. J. STARR 2,954,561
STAPLE MACHINE Filed Sept. 9, 1957 2 Sheets-Sheet 1 7a 8,2 Y@ 6 /ol 87 /02/07 afgani/LLI' un j/Ob HU/5w,
/g/d /00 /O /05 76 /967 5 Tlqfi- INVENTOR HENRY d.' STAP-R ATTORNEY H. J. STARR STAPLE MACHINE Oct. 4, 1960 Filed Slept. 9, 1957 2 Sheets-Sheet 2 ed f INVENTQR #Lf/Ry d. STARR MQ IM A oRNEY United States Patent() STAPLE MACHINE Henry J. Starr, 7 Sedgwick Ave., Darien, Conn. Filed sept. 9, 1957, ser. No. 682,812
9 Claims. (Cl. 1 49) This invention relates to new and useful improvements in staple driving machines.
In air-powered staplers, in order that the stapling mechanism be adapted for use in the fastening of a large variety of articles, it is necessary that the staple be driven into the material to be fastened with a maximum of force. The usual stapler heretofore Afrequently employed in the stapling of articles comprises an air piston having a driver element which propels a staple into fastening position. This type of stapler is objectionable in many instances since the distance the piston travels is relatively short and consequently the piston terminal velocity is considerably less than the optimum velocity that can be achieved for a given power source.
'This difficulty is eliminated when the movement of the piston is delayed until a sufficient air pressure has been built up behind the piston. With the full force of the air pressure behind the piston, the initial movement of the piston is sharp and quick and a high speed driving action is effected. It is also found that less power is required to operate a machine of this character.
Another diiculty involves the provision of an adequate supply of staples-normally the `amount of staples iitting in a staple track is determined by the track length. In order to provide an increased supply of staples, the track length must be lengthened which means the spring which feeds the staples is extremely long, and entire unit iscumbersome and diicult to manipulate.
This problem is eliminated by providing a staple magazine having two or more feed tracks. When the supply of staples in one -feed track is exhausted, a full feed track can be readily switched into operative position. 'Ihe result is a saving in the time-consuming operation of loading the stapler. In this manner, the progress of the work which has been stopped by Van empty staple track can be resumed with a minimum of delay.
It is, therefore, an important object of the present invention to provide an improved air powered stapler construction comprising an air valve and air-driven piston combination so constructed and arranged as to restrain movement of the piston during the opening of the air Valve and to permit a high speed movement of the piston after a sufficient buildup of air pressure for driving the piston has been effected.
Another object of the present invention is to provide an improved stapler having a novel magazine construction equipped with multiple feed tracks and having improved features for switching the feed tracks into operative positions.
Another object of the present invention is to provide a novel means for loading a magazine having `dual staple channels, wherein a pair of staple sticks in the as packed position, ie., oppositely facing overlapping position, may be handled as a unit and inserted into said staple channels, whereby simultaneous loading of said channels is eieoted.
Another object of the present invention is to provide a new and improved construction of an air powered stapler including an air valve, an air driven piston and a magazine assembly so constructed as to provide maximum utilization of the air supply in driving staples into a material to be fastened and affording novel means for loading a relatively large supply of staples. into the magazine unit. p
Other objects, features, and advantages of the present invention will be apparent from the following detailed description of certain preferred embodiments thereof taken in conjunction with the following drawings in which:
Fig. 1 is an elevational view partly in section of an air driven stapler unit constructed in accordance with the principles of the present invention;
Fig. 3 is an enlarged sectional view taken substan-` tially on the line 3 3 of Fig. 2 showing the locking cam for holding the stapler magazine cam in Ilocked position: Fig. 4 is a fragment of a sectional view similar to Fig. 3 showing the locking cam in its open position;
Fig. 5 is a view taken `along line 5 5 in Fig. 3;
Fig. 6 is a section on the line 6 6 of Fig. 3;
Fig. 7 is a section on the line 7 7 of Fig. 3;
Fig. 8 is the valve portion of the view shown in Fig. 1 but showing a modification thereof; p
Fig. 9 is longitudinal sectional view of a modified stapler magazine;
Fig. 10 is an enlarged sectional View taken along line 10 10 in Fig. 9;
Fig. 11 is an elevational view of the loading end of the modified stapler magazine shown 4in Fig. 9'
Fig. 12 is a view similar to Fig. 11, showing the posil tioning of the pusher element during the staple loading operation of the magazine; and
Fig. 13 is a sectional view taken along line 13 13 in Fig. 12.
Illustrated in Fig. 1 is a stapler unit 10 embodying the principles of the present invention and comprising an assembly of a hand grip portion or handle unit 12 rigidly secured to one end of a body portion or stapler housing generally indicated at 14 and a stapler magazine 16 attached to Ithe other end thereof. The body portion 14 comprises a cylinder 18 provided with a cup-shaped piston 20 which is slidably `disposed therein and normally held in its uppermost position by a piston return coil spring 22 having one end iitting within a recess or cup 24 the plug after air has been admitted into the cylinder. i
Pinned to the piston 20 is a staple driver 31 which reciprocates in a staple drive track 32 having an upper track portion 32a lower portion of the stapler housing 1'4 and a lower track portion 32b dened by a ,slotted jamb plate 33 fastened to the 4lower nose piece 34 of the body portion 14.
The handle 12 is provided with a longitudinal bore 36 which is internally threaded at its rear end to receive a n threaded pipe or supply line 37 which is connected to a` suitable source of compressed air. The bore 36 communicates with a valve chamber 38 provided with a removable servicing closure cap 40 which is gas-tightly l `threadedly attached in the upper surface of the handle 12,. Adjacent the forward end of the handle and below Patented Oct.V 4, 1960' projecting end or the valve chamber 38 is a vertical bore 41 having its upper end terminating at the valve chamber.
Proper sealing between the valve chamber 38 and the vertical bore 41 is provided in the valve chamber by a valve head 42 disposed in axialV alignment with the bore 41A and the cap 40. Normally, the valve head 42 is maintained in overlying and closed relation with respect tothefbore 41 -by means of a compression coil spring 43. disposed between the valve head 42 and the closure cap 40, the valve head having a cylindrical projection 44 which serves as a support for the lower end of the spring 43, and the cap 40 having a recess 46 of a diameter slightly larger than spring diameter to receive therein the upper end of the spring 43.
Slidable within the bore 41 is an elongated operating button 47 'which can be actuated by a button head or trigger as desired, a trigger 48 pivoted about a pivot pin 50 being shown and illustrated herein. The button 47 comprises a stepped cylindrical member having outer and inner portions 51, 52 which are integrally united at shoulder 53. Within the bore 41`is a spring 54 disposed about inner'button portion 52 which urges the button 47 away from the valve-closed end of the bore.
Also provided in the forward end of the handle \12 is a cylinder inlet port or passageway 56 which communicates with the cylinder 18 and the vertical bore 41. An exhaust passageway 57 cut in the handle 12 runs from the inner or upper end of the bore 41 to the outer or lower end of the bore 41, where it registers with a transverse opening 58 inthe outer button portion 51, and terminates at the handle surface. A blind end recess 59 in the lower-face of the valve head 42 provides a predetermined clearance space for Ithe free end of button portion 52 equal to or slightly greater than the diameter of the exhaust port 57 as seen most clearly in Figure l.
i Mounted within the handle 12 is a movable latch 60 which is adapted to releasably hold the piston against the plug 28 by reciprocably moving in an elongated cavity 61 which traverses bore 41. The traversing portions of the latch 60 and the operating button 47 are cut away so fasi-toprovide respec-tively a latch shank 62 incorporating a beveled face '63 land a correspondingly angled button face"64 engaging against the beveled face '63. In this manner the latch 60 is urged into piston locking position by a'latch spring -66 in the cavity 61. A latch shoulder `67 and cylinder flange 68 limits the projection of the latch 60into the cylinder 18.
In operation, as the trigger 48 is initially squeezed against the relatively weak pressure of the'spirng 54, the free end of the inner button portion 52 enters the clearance space 59 and the transverse button opening 58 moves past and out of registry with the exhaust port 57, thereby blocking the exhaust port 57. Continued depression of the button 47 /causes it to engage with the valve head 42 and thus raise the valve into the open position. As soon as the valve 42 is opened, air under pressure in valve chamber 38 will enter the inlet port 56 and the annular space behind the piston 20 delined by the cham-fered plug surface 30, and break the seal between the top face of the piston 20 and the plug 28.
Coincident with the initial opening of valve 42, the `angled button face l64 commences to retractingly cam the beveled vface 63 of the latch 60 against the pressure of the latch spring 66. The locking relation of the latch 60 and the piston 20 is maintained until the air flows -freely into the inlet port 56 and the latch 60 is suiciently retracted to clear the lower face of the piston 20. During this period, the valve 42 has time to reach its fully opened position and a plentiful supply of air under pressure is then available to drive the piston with a maximum of force.
.When the latch is so retracted that it clears the lower face of the piston 20, sudden movement of the piston will occur automatically. At that moment the quick action of the piston 20 will drive the staple driver 31 the drive track 32 with the full force of the air pressure behind it and drive a staple into the work with a maximum force. The drive of the piston is cushioned at the end of its travel by a suitably resilient pad 21 carried by the piston 20 and a shoulder or abutment 27, adjacent to the cylinder recess 26. By this arrangement a shorter driver movement having a more forceful driver movement than the conventional piston driver action may be effected.
Upon release of the trigger 48, the valve spring 43 seats the valve 42 against the end of bore 41, and the bore spring 54 moves the button opening 58 into registry with the exhaust port 57. Any suitable stop means may be used, the limiting pivotal movement of the trigger leg 49 against the staple housing 14 being illustrated herein.
Coincident with the registry of the buttonv opening S8 with the exhaust port 57, the piston spring 22 returns the piston 20 to its starting position, the piston depressing the latch 60 and overriding it into latching position. Y
'In this manner the speed' and uniformity of driver acp tion is constant for each staple driving operation and made independent of the operators touch Referring more particularly to Figs. l, 2 and 5, the nosepiece 34 is provided with a removable jamb plate 33 having a shallow slot which defines the lower end 32b of the drive track 32. This plate 33 rests against the nose piece and is held in position at its upper end by a plate tongue 70 which fits into a housing groove 70a. p lower end of the plate 33 contains a pair of hooked ears 71a which can be slidably guided along a complementarily formed channel 7'1b in the nose piece 34. A spring closure member 72 pivotally secured to the staple housing 14 and provided at its terminus with a detent 73 fits into a suitable aperture 74 in the jamb plate 33 to hold said `jamb plate in assembled position. In the event a staple tally-elongated, vertically-upright staple tracks 76 is disposed. The upper and lower peripheral edges of eac-h of the Yframe walls 75 is formed to provide an inwardly extending ange 77 which spacedly overlies the respective staple track 76 to `define a pair of open-ended slots 78a and 78h, see Figs. 6 and 7, and provide a pair of open-ended guideways, 80m and 8017, located in a longitudinal direction between said frame walls and said tracks for slidably receiving therein -a stick of staples 81a and 81b.
At spaced intervals along the length of the magazine 16 there is provided a series of transversely disposed stay bolts 82 which pass through registering opening provided for this purpose in the frame walls and the tracks 76 midway between the longitudinal edges thereof. 'Ilhese -bolts firmly fix the walls 75 `and tracks 76 in assembled position by means of track spacing sleeves 83 between the tracks 76, spacer rings 85 between the tracks 76 and the frame walls 75, and nuts 86 screwed on the outer ends of said stay bolts 82.
The tracks 76 include tapered rear portions 87 which extends rearwardly of the walls 75 and are slightly convergent to facilitate receiving a pair of staple sticks.
In accordance with the features of the present invention, a pair of staple sticks in the as packed position, i.e., oppositely Ifacing overlapping position, may be handled as a unit and inserted into the staple channels, a, vS0b. To illustrate, staple sticks packed in the usual way are arranged in pairs to form elongated, tubular passages of rectangular cross section. This pairing of staple sticks is utilized in the present invention to simultaneously load both staple Achannels of the magazine. This is accomplisfhed by inserting the free ends of tapered rear portions 87 into the hollow of the paired staple sticks and pushing the staple sticks into the magazine. As the staple The' NT t
Sticks are being pushed, they yield vertically `outwardly and horizontally outwardly in accordance with the guidance afforded by the tapered convergent rear portions 87, until the forward portions of the staple sticks pass over the high point of said portions 87. At this point, the forward portions of the staple sticks will have entered the staple channels 80a, 80b. Thereafter, as the staple sticks are pushed inwardly, they slide within the channels 80a, 80b until they reach the position illustrated in Fig. 1.
As shown most clearly in Figs. l land 3 the forward end of the magazine 16 is adapted to be received in the bite section formed by juncture of the bottom Wall 18a of the cylinder 13 with the rear face of the nose piece 34, the forward edges of the frame sides 75 and tracks 76 being in abutment with the nose piece, and the upper flanges 77 being slightly spaced from the underside of said cylinder. The nose piece 34 is provided with ya U- shaped feed slot 8S rin linear alignment with upper guideway `80a in the magazine 16, which allows free passage of the staples 81a from the staple guideway 80a into the drive track 32. The nose piece 34 also forms Ia stop for the lower stick of staples Slb.
An end wall 90, see Figs. 3 and 6, having a threaded opening therein is provided at the forward end of the tracks 76, and is pivotally secured to the nose piece 34 by a complementarily threaded bolt 91 which passes therethrough. In this manner, the entire magazine 16 may be pivotally rotated about the bolt 91 as an axis, whereby either of the sticks of staples 81a or l8119 may be rotatably moved into staple feed position, which of course obtains when either of the guideways 80a or 80b is in registry with the feed slot 88.
Indexing means Iare mounted on the staple housing 14 and magazine 16 for holding the staple parts in operating position, To this end, an upstanding stop bar 92 is secured, as by soldering, to one of the magazine walls 75, the stop bar extending at each end beyond the flanges 77 land being of such length as to abut the lower face 18a of the cylinder 18 when the feed slot 88 is in registry with the guideway 81a, Slb, respectively. Referring to Fig. 6 it will be seen that because of the opposition of the cylinder face 18a to the counterclockwise movement of the stop bar 92 only clockwise rotation of the magazine 16 about the pivot `bolt 91 is possible. Similarly, when the opposite end of said stop -bar abuts cylinder face 18a, only counterclockwise rotation of the magazine is possible. Thus it will lbe seen that the magazine 16 can be oscillated about the bolt 91 to successively `bring the staples from staple guideways '80a and `80b in operative position.
In order that the staple `guideway may be firmly retained in registry with the feed slot S8, locking means are provided. For this purpose, such means comprises a pair of oppositely projecting co-planar yokes or positioning ears 93a and 93b which bridge the magazine walls 75. 'I'he upper yoke 93a is clampingly held against the rear face 18h of the stapler body 14 by a dog or clamp 95 pivotally mounted on said rear face 18b. Referring particularly to Figs. 3 and 7, it will be seen that counterclockwise rotation of a thumb wing 96 causes the cammng surface 97 on the forward segment of clamp 95 to hold and lock the ear 93a fast against the housing face 18b yin the position shown in Fig. 3. Clockwise rotation of the thumb wing 96 frees the ear 93a', -as illustrated in Fig. 4, and allows the staple magazine 16 to be rotated in `a counterclockwise direction until the ear 9311 is in a position to be lockingly engaged by said clamp 95.
In order to feed staples uniformly into the feed slot 88 and thence into the ldrive track 32, there is provided a staple pusher assembly comprising U-shaped pusher elements 98a and 98h having cross sections similar in shape to staples 81 and which ride in the Staple guideways S0a and 801; respectively. Each pusher element, 98a, 98b, carries in its bight portion a sleeve 100, 100, through which passes a rod guide 101e, 101b. These 6 rods 101a, 101b are vertically spaced from each other and irmly secured at their ends to a cross piece or end wall 102 by means of set screws 103 in the manner illustrated in Figure 1.
The opposite ends of the rods 101 are slightly flared at 104 'to prevent disengagement of said rods from saidi sleeves 100. A slot 105 may be provided in the sleeve 100 to engage the flared end 104 and thereby avoid relative rotation between said rod and pusher element if so desired. A coil spring 106 disposed about each of the rod guides 101:1 and 101b resiliently moves the staple pusher toward the feed slot 88 and thereby uniformly urges the staples into the drive track 32. The staple pusher parts are held in assembly with the magazine 16 by means of elongated lingers 107, see Figs. 2 and 3, which are pivotally rockably mounted on the sides of cross piece 102 and provided with hooked ends 108 which llt in apertures 109 (see Fig. 1) in the convergent tapered ends 87 of tracks 76. Removal of the linger hooks 108- from engagement in the apertures 109 may be effected rby pressing the handle l10n of the lingers inwardly `against the pressure of linger spring 110b.
Referring to Figs l, 3, and 4, each of the pusher elements 98u and 98b is provided with a projecting tab 111 extending between and through the spaced flanges 77, which tab constitutes a stop catch to engage ia projection 1:12 on the clamp 95 and arrest the progress of the pusher element. This arresting action prevents the edge of the pusher element, for example 98a, from entering the drive track 32 and coming under the driver 31 when the guideway 80a is empty of staples. As shown in Fig. 3 when the guideway 80a is exhausted of staples 81a, the pusher 98a illustrated in dotted outline stops short of the drive track 32.
It will also be noted that under the conditions illustnated in Fig. 3 means must be provided for retraoting the staple pusher 98./zout of feed slot S8 before the magazine may be rotatably moved to bring `guideway 80b into feeding relation with respect to said feed slot. 88. For `this purpose, the clamp 95 is provided with a rear camming surface 113 which acts to retract the pusher element 98a out of engagement with the slot 88 simultaneously with the unclamping of the yoke 93a in the manner shown in Fig. 4. p
In the modification shown in Fig. 8, the operating button is provided with closely spaced, rounded openings 12.1, 122 for spherically seating the end 123 of latch 125. i
Also formed in the button 120 is a longitudinal groove 126 communicating with an exhaust port 127.
As the trigger 48 is initially pressed inwardly, the free end of the button 120 enters the clearance space 59, and iat `the same time the button causes the latch to ad- Vance through the cylinder wall yaperture 128 and ret-ain the cylinder piston 20, the latch 125 being held in this positi-on by the ridge 130 between the openings 121 yand 122. Simultaneously, the exhaust port 127 is closed by the initial movement of the button. Fuither movement of the button cracks the seal around the valve head 42 and allows compressed lair Ito flow therepast through the inlet port 56 and into the space behind the piston 20. The pressure of the piston 20 as a result of the free flow of air behind it, together with the fact that the button opening 122 has moved into registry with the latch end 123, causes retraction of the -latch 125 and allows the piston to start its driving stroke. The force of the -air pressure on top of the piston 20 'also helps to -move the latch 125 into retracted position, making the trigger squeeze very light, which is highly desirable. Upon release of the trigger 48, the button 120 springs back to its starting position and thereby pushes the latch laterally. The return stroke of the piston then returns the latch into engagement with the opening 121 and forces the air in the space behind the piston out through the exhaust port 127.
Fig. 9 illustrates va modied magazine assembly wherein the pusher assembly is permanently secured to the magazine 16. This is accomplished by providing a pair of pusher elements 13111, 13111, each of which is resiliently urged toward the nose end of the magazine by an elongated helical spring 13211, 132b. The springs 13211, 132b run between the staple tracks 76 and over sheaves 133:1, 133b, which are mounted on a common shaft 135, and terminate 'at pins 136, 136 fastened to the staple tracks 76, 76. Each track 76, 76 has a slot 137 yat its outer end which permits the pusher element 13111, 131b to be retracted out of the guideway 80a, Stil), so that the straight section 13811, 138b of the spring 13211, 13215, may be passed through the slot 137 and lodged in bracket 14011, 140]), disposed on the outer side of magazine in the manner illustrated in Figs. l2 and 13. In this manner both hands of the operator are available for use in reloading the magazine without the possibi-lity of dropping or misplacing the pusher elements.
It is noted that the handle unit, stapler housing and magazine constructions shown herein are merely illustrat-ive of the means which may be em-ployed for providing a stapler unit embodying the features of the present invention. The invention is not limited in this respect as any other suitable means or mechanism for effecting this function may be employed. Other modifications and variations may be effected without departing from the spirit and scope of the invention.
What is claimed is:
l. In combination with a stapler housing having a drivetrack, a staple driver movable in said drive track, and a feed slot for admitting staples into said drivetrack for driving a staple into a piece of work, a magazine pivotally mounted on said housing comprising a pair of spaced apart upper and lower elongated staple guideways, each guideway adapted toreceive a stick of staples, said upper guideway being normally fixed in registry with said feed slot, means for urging the stick of staples in said upper guideway through said feed slot into said drivetrack, said lower guideway being rotatably movable about the pivot axis of said magazine into registry with said feed track, said stapler having locking means cooperative with said housing and said magazine for firmly retaining said magazine and said housing in fixed position relative to each other when said magazine and said housing are disposed in operative position, said means for urging staples through said feed slot including a staple pusher, said staple pusher being -spring biased and `adapted to follow staples through said feed slot, and said locking means having an abutment thereon to prevent entry of said pusher into said drivetrack when said staples are exhausted.
2. In combination with a stapler housing having la drivetrack, .a staple `driver movable in said drive track, and a feed slot for admitting staples into said drivetrack for driving a staple into a piece of work7 a magazine pivotally mounted on said housing comprising a pair of spaced apart upper and lower elongated staple guideways, each guideway adapted to receive a stick of staples, said upper guideway being normally fixed in registry with said Ifeed slot, means for urging the stick of staples in said upper guideway 1through said feed slot into said idrivetrack, said lower guideway being rotatably lmovable about the pivot axis of said magazine into registry with said feed track, said stapler having iocking means cooperative with said housing and said magazine for firmly retaining said magazine and said housing in fixed position relative to each other when said magazine and said housing are disposed in operative position, said mean-s for urging 4staples through said feed slot including a staple pusher, said staple pusher being spring biased and adapted to follow staples .through said feed slot, and said locking means having an abutment thereon to retract said pusher from said feed -slot when said locking means'is'unlocketktracks each having a tapered convergent extension, whereby a pair of sticks of U-staples arranged with the leg portions of each stick disposed respectively -inside and outside the leg portions of the other stick may be readily received on said track extensions and guidably moved linto said staple channels.
4. A reversible magazine having dual staple channels. comprising a pair of spaced apart, substantially parallel` staple tracks adapted to be straddled at the top thereof by a stick of staples having depending legs and at the bottom thereof by a stick of staples having upstanding legs and a pair of side walls straddling said tracks and defining with said tracks dual staple channels for receiving said sticks of staples, respectively.
5. A magazine according vto claim 4, said -tracks having tapered convergent extension-s to guidably receive Ysaid sticks of staples.
6. In combination with the magazine of claim 4, a stapler housing having a drive track provided therein with -a staple feed slot and a staple driver, said magazine being pivotably mounted on said stapler housing for selective registry of said staple feed slot with each of said staple tracks.
7. A combination according to claim 6, said magazine and said housing having interlocking coopera-tive means for securing said staple feed slot in selective registry with each of said staple tracks.
S. A combination according to claim 7, a staple pusher mounted in said magazine for urging staples through said feed slot, and an abutment on said interlocking cooperative means to prevent entry of said pusher into said drivetrack when said staples are exhausted.
9. A reversible magazine having dual staple channels comprising a pair of spaced apart, substantially parallel staple tracks adapted to be straddled at the top thereof by a stick of staples having depending legs and at the bottom thereof by a stick of staples having upstanding legs and a pair of side walls straddling said tracks and defining with said tracks dual staple channeis for receiving said `sticks of staples, respectively, said tracks having tapered convergent extensions extending beyond said sidewalls, a pair yof spring 'biased staple pushers connected to said magazine and removably insertable in said staple channels respectively, and bracket means on said extensions for holding said pushers, whereby the insertion of sticks of `staples in said channels is facilitated.
References Cited in the file of this patent UNITED STATES PATENTS 2,368,552 LaPlace Jan..30, 1945 2,585,942 Juilfs Feb, 19, 1952 2,671,214 luilfs Mar. 9, 1954 2,771,609 Klopstock Nov. 27, 1956 2,781,515 Iuilfs Feb. 19, 1957 2,792,571 Klopstock May 21, 1957 2,801,418 Jenny Aug. 6r, 1957 2,818,570 Faccau Ian. 7, 1958