US2239963A

US2239963A - Stapling machine

Info

Publication number: US2239963A
Application number: US225473A
Authority: US
Inventors: Roy G Hoffert
Original assignee: AJAX TOOL AND DIE Co
Current assignee: AJAX TOOL AND DIE Co
Priority date: 1938-08-17
Filing date: 1938-08-17
Publication date: 1941-04-29
Anticipated expiration: 1958-04-29

Description

April 29, 1941. R. G. HOFFERT 2,239,963

STAPL'ING MACHINE Fled'Aug. 17, 1938 56 54 2 39 X05 L Y' )l J5 M 12gi f5 45 55:' 57 55 Z3 2 2 l i5 024? S 7 25 5X6 28 l 42 l J5 Z/v, 4,22 6k ATTORNEY.

Patented Apr. 29, 1941 STAPLING MACHINE Roy G. Hoffert, Racine, Wis., assignor to Ajax Tool and Die Company, Racine, Wis., a corporation of Wisconsin Applicatien August 17, 1938, Serial No. 225,473

9 Claims. (Cl. 1 3) This invention relates to stapling machines, particularly for desk use. t

An object of the present invention is to smplify and otherwise improve stapling machines of the type mentioned.

Another object is to provide an eiective, du-

v rable, foolproof stapling machine that may be inexpensively produced.

Other more'specic objects and advantages will appear, expressed or implied, from the following description of a stapling machine constructed in accordance with the present invention.

In the accompanying drawing:

Figure 1 is a llongitudinal sectional view of a stapling machine embodying the present invention.

Fig. 2 is a horizontal sectional view taken substantially along the line 2 2 of Fig. 1.

Fig. 3 is a Vertical transverse sectional viewv taken substantially along the line 3 3 of Fig. 1.

Fig. 4 is an enlarged sectional View of the lower front portion of the stapling arm shown in Fig. 1, with the plunger in depressed position.

The stap-ling machine selected for illustration comprises a base Il! in thev form of a flanged sheet metal stamping, recessed adjacent oneend to receive and support I a conventionalv fixed clincher die I I, and having not far from its other end a pair of struck-upears I2 between which a stapling arm I3 is rockably supported.

In this instance a bolt I4, passing through the ears I2 and through the arm, constitutes a fulcrum support for the latter, and a leaf spring I5,

releasably attached at one end I6 to the base I0 rearwardly of the bolt I4, and bearing at its other end I1 ,against the arm I3 forwardly of the bolt, yieldably retains the forward end of the arm elevated above the base so as to provide the usual entrance throat between the base and arm into which material to be stapled may be entered in the usual manner. 'I'he lower end It of the spring is shown engaged in a slot I8 formed in the base I0 and shaped to provide cantilever support therefor, the spring being retained by -a lug I9 on the base which lug projects into the slot I8 and through an appropriate hole in the spring I.

The stapling arm` I3 shown is of sheet metal. It comprises longitudinally extended, laterally spaced, upright side plates 20, joined along their lower margins by an intermediate core member 2|, riveted or otherwise rigidly xed thereto, and additionally rigidly joined at their forward ends by a vertical end plate 22 bent to `embrace and substantially close the forward end of the arm and riveted or otherwise fixed thereto. The arm thus constitutes a rigid box-like structure which is preferably additionally braced by a horizontal 3 cross-plate 23 joining upper portions of the side plates 20 not far from their rear ends.

The core member 2| constitutes a support and guide for a conventional train of staples S` and cooperates with the side plates 20 (see Fig. 3) of *.v the arm to form a magazine for the staples. The

core member 2| in this instance comprises a hollow sheet metal stamping of inverted channel form, the upper portion thereof being laterally reduced to accommodate in the usual manner the Y depending legs of the staples between it and the -meta1 stamping of inverted `channel form slidably mounted upon and loosely embracing the core member. The follower 25 is provided with upstanding ears 26 perforated to slidably receive a spring retainer rod 21 having a compression spring 28. thereon interposed between the rearward ear 26 of the follower and a lug formation 29 on the rod. The rod 21 extends loosely above and lengthwise of the core 2| and is provided at its forward end with a lug lformation 3|) adapted ".to limit the forward advance of the follower 25 by engagement with the forward ear 26 thereof. The rod 21 is positioned by the earsl 2S on the follower and by an appropriate hook formation 3| at its rear end adapted to releasably engage a perforation 32 in the rear end of the core.

The arrangement is such that the spring 28, acting against the rear follower ear 25, urges the follower 25 and the staples forwardly, and thus maintains the foremost staple of the train against the forward end plate 22 of the stapling ytical end plate 22 so as toA form therewith a narrow vertical guideway through which the foremost staple of the staple train may be vertically ejected. Above this guideway and vertically aligned therewith is a staple driver 33 which, in the device shown, comprises a steel plate slidalbly seated face-to-face against the end plate 22 and depending from an appropriate actuating plunger 34 to which it is securely attached by riveting or otherwise. In this instance the plunger 34 is of tubular form, rectangular in cross-section, and dimensioned to provide a close sliding fit within the vertical guide channel formed by and between the side plates 23 and the end plate 22 of the stapling arm. A bolt 35, passing through the side plates and through a Vertical slot 36 in the plunger, retains the plunger in proper working position within this guide channel.

The plunger 34 is yieldably retained in the upper position shown by a leaf spring 3'I, releasably held at its lower end 38 in the crossplate 23 in a manner similar to the mounting of the spring I5 above described, and reduced at its upper end to form a tongue 39 engaged in an appropriate slot in the plunger 34. The plunger carries an operating head 4-preferably eccentrically disposed slightly rearwardly of the axis of the plunger and of the guide bolt 35.

It will of course be understood that papers or other material to be stapled are inserted between the clincher die I I and the elevated end of the stapling arm I3, and that upon applying a downward blow to the plunger head 4I), the end of the stapling arm is vfirst depressed into contact with the papers, and that thereafter the plunger 34 and driver plate 33 descend through the vertical guideway at the end of the arm 22, driving ahead of it the foremost staple of the train and causing the staple to penetrate and to be clinched onto the papers in a well known manner.

In stapling machines of this type, a return of the plunger and staple driver to upper position, after a partial depression of the latter, will sometimes permit partial entry of a second staple into the narrow vertical guideway before the foremost staple has been lowered suiiiciently to clear the second staple. This results in clogging of the guideway. In the machine shown, provision is made to avoid this difliculty by automatically returning the first or foremost staple into its original upper position in the event that it has not been depressed sufficiently to avoid interference with the next staple. For this purpose, a spring clip 4I is provided (see Figs. 1 and 4), the clip shown being formed of a strip of spring steel bent into loop form with one leg 42 riveted or otherwise attached to the end plate 22 and the other leg 43 extending substantially horizontally through the vertical staple guideway and through the foremost staple in the staple train. l

The arrangement is such that, as the driver plate 33 is forced downwardly forcing a staple ahead of it, the staple engages the lower leg 43 of the clip, depressing the same and deiiecting the clip toward the position shown in Fig 4, permitting the staple and driver ultimately to continue downwardly into staple clinching position. However, in the event that the driver plate 33 is returned to upper position before the staple has been depressed clear of the clip, the lower leg 43 of the clip, urging the staple upwardly. causes the staple to follow the driver plate 33 on its upward return movement, and thereby prevents entry of a second staple into the narrow vertical guideway.

In the machine shown, the stapling arm I3 and parts carried thereby are substantially wholly enclosed by an appropriate housing which in this instance comprises two separable shells 44 each having an inturned flange 45 adapted to abut the flange of the other member substantially throughout the forward end and top of the housing, the flanges having appropriate mating recesses to accommodate the clip 4I, the plunger 34, the rear end of the core 2| and associated rod 21 and staple feed mechanism. 'Ihe shells 44 are retained in position preferably by the two bolts I4 and 35 which extend through them.

Various changes may be made in the embodiment of the invention hereinabove specifically described without departing from or sacrificing the advantages of the invention as defined in the appended claims.

I claim:

1. In a stapling machine,a stapling arm, a staple magazine extending length-wise of and within said arm, staple driving means at one end of said arm operable to eject one staple at a time from said magazine and a resilient clip attached to the same end of said arm, said clip projecting forwardly from said arm and being doubled back upon itself to form an inwardly directed leg normally projecting across the path of travel of the ejected staples for the purpose described.

2. In a stapling machine, a stapling arm having a staple magazine extending lengthwise of and within said arm, staple driving means at the forward end of said arm operable to eject staples one at a time from said magazine, and a resilient substantially U-shaped clip having a lower leg normally projecting across the path of travel of the ejected staples, and a resilient upper leg attached to the forward end of said arm for resiliently suspending said first named leg forwardly of said arm.

3. In a stapling machine, a staple arm, a staple magazine extending lengthwise of and within said arm, staple driving means at the forward end of said arm operable to eject one staple at a time from said magazine, a strip hav- '.ing a portion normally projecting across the path of travel of the ejected staples and havingr a portion disposed substantially forward of said Vpath, and resilient means connecting the forward portion of said strip with said arm and :forming a resilient suspension for said strip permitting movement of the suspension point under the influence of said staple driving means while resiliently urging said strip into normal position between operations of said staple driving means.

4. In a stapling machine the combination of a base. a frame rockably supported on said base and forming a stapling arm, a separate housing attached to and enclosing said frame and rockable therewith, and staple feeding and driving mechanism carried by said frame independently of said housing, said mechanism being enclosed in said housing and including an actuator projecting through said housing.

5. In a stapling machine the combination of a base, a frame forming a stapling arm. means including an element for rockably supporting said arm on said base, a separate housing enclosing said frame and rockable therewith. means including said element securing said housing to said frame, and staple feeding and driving mechanism carried by said frame independently of said housing, said mechanism being enclosed within said housing and including actuating means projecting from said housing.

6. In a stapling mechanism, the combination of a base, a clincher die thereon, a stapling arm, means including a bolt for rockably supporting said arm on said base, staple driving mechanism including a plunger carried by said arm, a second bolt in said arm for retaining said plunger in Working position, and a two-part housing carried by and rockable with said arm for enclosing said arm and mechanism, each of said bolts extending through both parts of said housing for securing said parts together and on said arm.

7. In a device of the character described, the combination with a base, of a stapling head frame tiltable with respect to the base, pintle means providing a fulcrum upon which said frame is tiltable, stapling mechanism in the head operatively mounted on the frame, and a casing enclosing said frame and mechanism through which said pintle means extends, said casing comprising separable parts and said pintle means comprising means whereby said parts are secured together.

8. In a device of the character described, the combination with a base, of a tiltable stapling head pivotally connected with the base, a casing comprising two shallow box-like parts having marginal flanges in edge abutment and enclosing said head, a rod extending transversely through the head, stapling mechanism guided in part on said rod for movement within the head, and means at the ends of said rod engaging said casing parts to maintain them in assembly upon the head.

9'. In a device of the character described, the combination with a base, of a stapling head frame pivotally connected with the base for tiltable movement with respect thereto, stapling mechanism operatively mounted on the frame to tilt therewith and including a plunger provided With a staple driver and a follower slide provided with a compression spring and spring guide rod, and a casing enclosing said frame and stap-ling mechanism and provided with openings for the plunger and the rod, said casing comprising shallow box-like parts at opposite sides of the frame having complementary flanges in marginal abutment, said flanges being notched at corresponding points to provide openings for the plunger and the guide rod respectively, and means for maintaining said casing parts in assembly.

ROY G. HOFFERT.