US2234448A - Method of fastening and apparatus therefor - Google Patents

Description

March 11, 1941. E. R. PosNAcK METHOD OF FASTENING AND APPARATUS THEREFOR Filed Nov. 4, 1,958 2 Sheets-Sheet 1 Afl/25 March 11, 1941. E. R. PosNAcK METHOD OF FASTENIG AND APPARATUS THEREFOR Filed Nov. 4, 195e 2 Sheets-Sheet 2 `lNvx-:NTOR

Patented Mar. il, 94l

UNE'EED STATES METHOD 0F FASTENING AND APPARATUS THEREFOR Emanuel R. Posnack, New York, N. Y. Application November 4, 1938, Serial No. 238,820

14 Claims.

This invention relates to fastening methods and devices for securing together several sheets or layers of paper or other material, as well' as for effecting temporary or permanent closures for containers made of corrugated board and the like, forv top and bottom sealing, and for tacking, tagging or similar operations, this being a continuation in part of my application filed on March 3, 1937, Serial No. 128,832, and which matured into Patent No. 2,172,259. r

In the several conventional methods of stapling, the most commonly employed staple is that having two prongs or legs, either straight or substantially arcuate, driven into the work by a plunger traveling normal to the plane of the work. Another form of fastener, only occasionally employed, is the single-legged or fiat Wire type the top and bottom of which are clenched by o positive deflecting means such as by a top and bottom anvil-this type of fastener also being driven by a plunger moving perpendicularly to the surface of the work. Both of these fasteners involve the use of relatively intricate clenching 0r deflecting mechanisms, and the fasteners themselves, particularly of the two-legged type, are usually quite expensive due to the length of the wire stock and the forming operations'required to produce them. It is within the contemplation of my invention to overcome these short-comings by simplifying fastening operations and reducing the cost thereofan objective which I attain by employing an inclined drive with single-legged fasteners also inclined with respect to the surface of the work. By means of such method. a rela- 35 tively simple and inexpensive fastener can readily be drivenint'o the work whereby the material being fastened'will, in certain forms of my invention where the fastener is formed with a head, l be held between the head and the inclined leg 40 of the fastener to resist a vertical upward pull.

A further object of my invention is to enable single-legged fasteners arranged in stack formation to be readily and positively detached from the stack one at a time upon theoperative stroke 5 of the plunger.

, It is also within the contemplation ofthis invention to employ a preferably straight singlelegged fastener to bedriven into the work simultaneously with the formation' of a head thereon whereby the device serves both .as a fastener forming and driving mechanism. Due to the employment of an inclined' drive, a collapse of the upper portion-of the partially driven inclined fastener against the work can be effected when the support for the fastener is either eliminated or retracted, thereby obviating the necessity of 'employing special dies or anvils for forming the top head of the fastener.

Another object of this invention is to provide a fastener whereby` a secure operative grip upon the work will be effected by employing the method above referred to. and whereby a plurality of fasteners adapted to be driven thereby can be economically housed in the driving mechanism.

It is also within the contemplation of this invention to enable afastener to be clenchedor bent within the work without the use of an underlying anvil, an objective which is attained by causing the prongor leg of the fastener being driven to be curled into the work due to the engagement thereof with a relatively rigid member positioned upon the work, preferably aided by the resistance afforded by the material being fastened.

Another object of this invention is to enable the method above-referred-to to be used in conjunction with an Iunderlying anvil whereby it can `be employed particularly for bottom sealing of cartons, and for the fastening together of several sheets of paper substantially in the manner of other. conventional desk stapling devices.

And it is also within the contemplation of my invention to enable -the above method to be effectively performed by employing fasteners of the aforesaid type conveniently contained in novel stack formation.

Other objects, features and advantages will' appear from the drawings and the description hereinafter given.

In the drawings, Y

Figure 1 is a perspective view of a preferred form of fastener employed Vin connection with this invention.

Figure 2 is a perspective view of a stack of inclined fasteners substantially similar to theform of Figure l.

Figure 3 is a fragmentary. vertical section of a device employing one method of my invention, the drawing showing the fastener driven into the work by an inclined plunger.

Figure 4 is a, fragmentary vertical sectionof another machine embodying my invention and adapted to house a stack of fasteners, showing by broken lines a fastener driven completely into thev work.

Figure 5 is a section of Figure 4 taken along line 5 5. y

A Figure 6 is a fragmentary vertical section of another-dorm of my invention illustrating a retractable mechanism for causing a, collapse of the fasteners during thedriving operation to form a head thereon, as indicated by broken lines.

Figure 7 is a fragmentary side elevation illustrating the front portion of the machine of Figure 6 with the plunger in a raised position and the retractable mechanism in its forward position.

Figure 8 is a view similar to Figure 7 showing the plunger at the completion of its stroke and in its retracted position.

Figure 9 is a fragmentary sectional plan of Figure 7 taken along line ,Q -9.

to form a head thereon, the plunger and fastener y holding mechanism being in their retracted posi--y tions. f

Figure 13 is a fragmentary vertical section of a structure similar to that of Figure 12 but with the plunger containing a downwardly protruding portion to cause an additional bending ofthe head of the fastener into the work.

Figure 14 is a vertical section of a modified form of my invention, the driving plunger con--v taining a pivotally supported tip for forming a head on the fastener, the plunger being shown in a partly raised position.

Figure l5 shows the position of certain` of the parts of the device of Figure 14 after a completion of the driving stroke.

Figure 16 is a fragmentary vertical section of another modification of my invention, containing a def-lecting element at the base of the machine. the broken lines showing the approximate driven `position of the fastener after encountering the deflecting element.

Figure 17 is a fragmentary vertical section of a device similar to that shown in Figures 11 and 12 but with an underlying anvil to cause a positive defiection of the lowermost portion of the fastener. v

Figure 18 represents the parts of Figure 17 in their nal operative positions after the retraction of the fastener and plunger supporting Y structure, showing the formation of the complete clench. t

Figure 19 is a fragmentary side elevation of the structure of Figure 17, and

Figure 20 is a semi-diagrammatic representation of a form of my invention illustrating the manner in which a positive severance of a fastener can be effectuated by a slightly inclined plunger.

In the forms of my invention as described in my said Patent No. 2,172,259, one or more staples, each containing a head portion substantially parallel to the Work and a leg portion inclined with respect thereto, is driven downwardly by one or more inclined plungers whereby, upon the completion of the stroke, the head portion of each staple will engage the surface of the work'and the penetrating portion thereof will be inclined at an angle thereto. Hence in this position the head and penetrating portions of the staple will hold therebetween the portion of the material being stapled, which will obviously present a resistance to a straight upward vertical pull exerted upon the staple. A detailed description of the gripping action of a staple thus driven has been adequately vset forth in the said Patent No. 2,172,259, and hence will not be repeated here. However, it is intended by my present invention toobviate the use of -a preformed staple containing a head thereon, and to obtain a substantially similar eect by employing only a simple straight strip of flat wire which, during the driving operation in accordance with certain forms of this invention, will be deformed to provide a driven fastener presenting a head and an inclined leg similar to the performed staple described in my said Patent No. 2,172,259. And in this aspect of my invention, it is a further objective to effectuate a drive of an inclined fastener for obtaining an operative grip upon the work without the necessity 'of forming a head thereon, as will more `specifically hereinafter appear.

In all the forms of my invention illustrated in my said Patent No. 2,172,259, the penetrating leg of the staple is shown as extendingl straight -into the material. This will obviously occur when the toughness or density of the material being stapled is not sufficient to cause a bending of the leg of the staple. However, in certain types of corrugated board with a tough. upper layer, or in dense cardboard or fibre board, the material may .afford a partial resistance to penetration. Thus, in Figure 3, aswell asin certain other figures ofthe drawings herein, the ultimate shape of 'the fastener may be slightly curved, particularly' if the terminal point of the fastener is bevelled as indicated. In each of these cases, the fastener illustrated is not sufficiently rigid to completely withstand thebending effect produced by the drive of the plunger and the resistance afforded by the material being fastened. thereby causing a slight curvature of the fastener as it il being driven. This tendency to produce curved driven fasteners is enhanced particularly in those structures where th driven fastener is in effect an inclined column supported during its driving movement only at two points-the wall of the penetrated portion of the work, and the lower portion of the fastener supporting member which is spaced above the work-as exemplified by the structures of Figures 6 and 11 to 18.` Where itis, however, desired to obtain a more positive clench, the structure oi' Figures 17, 18 and 19 can be used wherein an underlying anvil is employed, all in a manner to be more fully hereinafter set forth.

Where a drive of considerable inclination is employed, the fastener deecting tendency of the material being fastened can be advantageously utilized for various purposes, including that of effecting temporary closures. 'I'hus in Figure 3, the two abutting portions and 28 are held together by the straight wire fastener 21 driven into the work'by the plunger 28. It will be noted that the base 29 of the machine rests flatly upon -the surface of the work and contains an inclinedk channel therein for plunger 28, said plunger being adapted to penetrate the surface of the work to practically hide the fastener from view. The terminal point 30being bevelled as indicated, will cooperate with the material to cause an upward deflection of the fastener, although a satisfactory temporary closure can obviously be effected with a straight substantially unbent fastener driven into the work at a considerable inclination.

Where it is desired to economically house a relatively large number of fasteners in a suitable driving machine, to be driven in accordance'with the methods of my invention, I prefer the employment of a stack of straight fasteners secured Y togetherby any conventional adhesive means.

the fasteners being disposed at an inclination to the longitudinal direction of the stack, similar in arrangement to the stack 3l .shown in Figure -2, or the stack-s of fasteners illustrated in Figures 4, 6 and 1l of the drawings. Each individual fastener is preferablybevelled at the bottom edge 32 thereof (see Figure 2), the uppermost edge 33 of each fastener being preferably normal to thev front and rear sides thereof. Hence a stack of fasteners of my invention contains a stepped formation at the upper edge thereof so that the division between the individual fasteners is well defined, as' distinguished from certain conventional stacks of fasteners that are adapted to 'be driven in a direction normal to the plane of the work thereby presenting 'an upper edge of the stack of such smoothness as to render the lines of demarcation between adjacent fasteners hardly discernible. With this stepped formation of the inclined stack of fasteners, a driving plunger can be made to separate a fastener from l its stack more readily than with the aforesaid conventional arrangement where there always is some danger that the slightest play in the driving plunger may cause it to engage the next adjacent fastener and inadvertently detach it from the stack.

To more clearly understand this action, reference will be made to Figures 4, 6 and 20 in which stacks of fasteners similar to that of Figure 2 are employed. In Figure 4, the foremost staple 34 is in abutment with the front fastener 35, the stack of fasteners being operatively supported upon the fastener rack or base 36 Within the framework 31 of the machine. The stack of fasteners is urged forwardly by the push member 38 under the influence of spring 39 in the conventional manner wel] known in the art. The plunger 4D is movable within the channel 4| in the direction of the inclination of the fasteners, and is positioned to drive the foremost fastener into the'work 42, In this form of my invention.

it is preferred that the thickness of plunger 40 be no greater, and preferably less than the thickness of the underlying fasteners such as 34.

It will be noted that the uppermost edge 43 of fastener 34 projects above the most proximate portion 44 of the next adjacent fastener 45, so that the plunger 40 definitely encounters only the fastener 34 at the beginning of its downward drive. As the drive continues, the detached foremost fastener 34 will be driven into the work as indicated by the broken lines; and if, as in the structure illustrated, the plunger 4I is designed to extend at the completion of its operative drive slightly below the base 39. it will cause a countersinking of the driven fastener. It will also be observed that the fastener may be slightly bent due to the bevelled point thereof and the resistance of the material 42, for the reasons hereinabove set forth.

In Figure 6, a detailed description of which will be hereinafter set forth, the plunger 41 is positoned at that end of the stack opposite from the plungers position in Figure 4. so that fastener 46 is in the foremost position ready to receive the operative drive of said plunger 41. It will be noted that, in the structure illustrated, the uppermost edge 48 of fastener 46 will receive the first impact of the plunger, being closest thereto-and hence will cause said foremost fastener 46 to be detached from the stack the instant after the plunger reaches the level of point 4S.

In Figure 20, the driving edge 41o of the plunger 41a is operatively cngageable with the upper edges 33a of the fasteners 3la. The plunger is in this form of my invention, directed downwardly at a lesser inclination than that ofy the fasteners. Upon a downward operative movement of the plunger, the driving edge 41b will engage the top edge 33a of the underlyingl fastener to detach it from the stack and driveit downwardly. It is apparent that thewall 33o of the second fastener, exposed to the plunger because of the stepped formation of the top edge of the stack, will receive the lowermost point 41e of theplunger and prevent lit from sliding rearwardly (because of excessive play or looseness for any -other reason) and inadvertently engaging the top of the second staple. During the continued driving movement of the plunger the stack of fasteners will be urged rearwardly against the action of spring 55a, leaving room for the plunger in its lowermost Adriving position, as indicated by dot-dash lines in the figure.

The positive detaching and driving action above described is primarily due to the inclined a straight inclined drive in the aforementioned manner is effected for the major portion of the stroke, leaving a portion of the fastener protruding upwardly at an inclination in the form of what` may be considered an inclined column. Thereafter the fastener supporting means is retracted and the plunger permitted to continue in a general downward direction, thereby forcing the said upward projecting inclined column to be collapsed against the surface of the work. In

this manner a straight single-legged fastener consisting only of a single strip of wire is operatively driven into the work and shaped into a form having a head and leg portion embracing therebetween a portion of the'work. as illustrated in Figure 12 and other guresin the drawings.

One method by which this operation is effectuated within the scope of my invention is shown in Figures 6 to 12 inclusive. The base 49 of the machine is adapted to rest upon the surface 50 of the work; and .in spaced relation to the base is the fastener supporting floor 5I upon which the stack 52 of inclined fasteners is supported. The entire stack is operatively housed within the casing 53 which, together with supporting floor 5|, constitutes a fastener magazine. Slldably supported within the magazine isthe push member 54 urged forwardly by the spring 55 in conventional manner. the specific anchorage of the spring not being shown inasmuch as it may'be of conventional structure well known in the art.

engagement with the wall 51 constituting part' of the framework 58 of the machine. It is not deemed necessary to showv the details of the entirestructure inasmuch as that is not essential for ,a complete understanding. of this invention. The relative position of the parts during the various operating conditions have been clearly shown in Figures 6 to 12 inclusive.

The front plate 59 contains an inwardly extending guide member 60 in constant abutment with the foremost fastener 46, the 'width of said guide member being such as to permit said foremost fastener 46 to project forwardly a sufficient amount under the influence of spring 55 to enable it to be operatively driven by plunger 41, and particularly to permit said driven fastener'to slidably move between the said guidermember 88 and the second fastener 8l. In one arrangement of my invention, the said guide member contains a single wall intermediate the lateral edges of the foremost fastener, the plunger 41 having bifurcated terminals 82 and 88 to straddle said guiding member 80, as clearly indicated in Figure 9.

Referring particularly to Figures 7 to 10 inclusive, it will be noted that the lateral walls 88 and 81 contain slotted portions 88 of substantially L-shaped formation, the upper portion 88 extending in a direction parallel to the inclination of the driver, and the lower portion 18 extending rearwardly and downwardly. Pivotally attached at point 1| at the base of the machine are the actuators 12 each consisting of an arm and upper terminal portion 13 positioned adjacent the said lower portion 10 of the slot 88. The arms 12 are each so positioned and so mounted that upon a pivotal or rotatable movement thereof, the terminals 13 will move along the path of said lower slot 18. The said actuators 12 are each normally maintained by springs 14 in an elevated position so that said terminals 13 are positioned substantially at the bottom of upper slot 88. And it should further be observed that the said lower slot 10 is inclined rearwardly in a direction intersecting the foremost portion 18 of the casing 88, said foremost portion being of U-shaped cross-section and adapted to slidably embrace the plunger 41. In other words, portion 18 constitutes a three-n sided housing for slidably supporting the plunger 41 during its operative stroke.

-The plunger carries, inthe region of the lower portion thereof, the two outwardly extending pins 18 slidably movable within the said slot 88; and suitably attached upon the extremities of these pins are the contactors 11 extending beyond the lateral walls 68 and 81 of the framework of the device, the undersides of these contacting elements being recessed to enable them to operatively receive the upper terminals 18 of actuators 12 in a manner to be hereinafter set forth.

Upon an operative driving stroke of the plunger 41, the said pins 18 slidably move within the upper inclined portions 88 of'slots 88 until the contacting elements 11 engage the terminals 18 of the actuators 12. Such anengagement will cause a counter-clockwise pivotal rotation of said actuators, carrying with it the contacting elements 11 and the pins 18 along the path of the lower portion 18 of slot 88. Inasmuch as the said pins are flxedly attached to the plunger 41, the entire plunger will be rearwardly actuated thereby exerting a rearward pressure upon the entire housing 83 against the action of spring 88, to cause retraction of the housing and the fasteners carried thereby. This retraction occurs before the termination of the driving stroke of plunger 41. inasmuch as the rearward movement of the pins 18 occurs substantially at the juncture of slotted portions 88 and 18. Hence just before retraction starts, there is an `upwardly inclined portion of the driven fastener protruding from the work; and' as the plunger continues downwardly and rearwardly during its operative stroke it will cause a bending and subsequent collapse of the said protruding portion of the fastener against the surface of the work,'all as will be more clearly hereinafter set forth.

By referring particularly to Figures 11 and 1,2

the above-described action will be clearly under'- .pivotally mounted tip 84.

stood. In Figure l1 the fastener 48 has been partly driven into the work under the influence of the plunger 41, the housing 88 and the plunger being in their respective positions Just prior to the beginning of the retreating operation above downwardly directed drive in the general direction of the inclination of the fasteners. It should be noted here that the base 8| of housing 53 is elevated above the surface of the work being fastened, forming a space 18 thereabove. Preferably at this point retraction of housing 88 occurs, in the direction of the arrow shown in Figure 14, all in the manner above described. Obviously the plunger ln moving with the housing 83 towards the left will continue its operative engagement with the unsupported inclined top portion 46a of the fastener to cause a collapse thereof against the surface 80 of the work. Hence a head will be formed on the fastener upon the completion of the driving action of the plunger, which, together with the penetrating portion of the fastener, yembraces therebetween a portion of the adjacent material being fastened. In this manner Ithe driven fastener can effectively serve, among other purposes, that of a tacker or temporary sealing device. When the base of the plunger 41d (see Figure 13) contains a downwardly extending projection 18, the portion of the head 80 underlying the projection will be bent downwardly to produce the burr 8|, thereby effectuating a still stronger clench.

Instead of employing a retractable guide for the plunger, such as the housing 84 of the forms above described, a stationary magazine and guide 82 (see Figures 14 vand 15) can be used, the plunger containing at the lower portion thereof a Upon a downward movement of the plunger between guide 82 and front wall 88, the fastener 88 will be driven downwardly into the work in the manner hereinabove described. But when the said tip 84 of the plunger reaches the spaces 81 between the base 82a' and the work 88, it will tend to straighten itself out in a direction substantially normal to the surface of the work, inasmuch as it is no longer being confined within its oblique path when the wall guide 88 is no longer in engagement therewith. In the preferred form. the abutment 88, yieldably urged by spring 88 towards the channel `8| so that the extreme terminal 82 of the abutment extends-slightly into said channel, will in-V tercept the bevelled lower portion 88 of the tipl pact. It is thus apparent that upon a completion of the operative stroke, the upper portion of the fastener, comprising an unsupported inclined column, will be collapsed downwardly against the work under the influence of plunger 88 to form a head 88a thereon. The stack of fasteners, being adhesively secured together, as aforesaid, can be operatively moved forwardly or maintained in place within magazine 82 as a unit. It may be held in place and moved forwardly manually so that the foremost fastener underlies the plunger. or the stack may be moved forwardly by any other means within the contemplation of this 'invention; and if spring means like 88 (Figure 6) are used to urge the stack of fasteners forwardly a guide member like 60 can be employed to hold the fasteners against being forwardly expelled when the plunger is fully raised.

In most of the forms hereinabove, described, the fastener is shown to curl inwardly, due primarily to the resistance afforded by the work being fastened and the bevelled penetrating point of the staple. In Figure 16, the curling effect is more positively obtained by providing an abutment 94 positioned at the `base of the machine and being urged by spring 95 to its foremost position as indicated in said figure. It will be noted that said abutment is positioned in the path of the fastener moving under the driving force of plunger 01. During the operative movement of the fastener, it will obviously engage the wall of the abutment 94 and be deflected thereby in such manner as to cause it to curl into the work as shown in the drawings, the space 98 permitting such an action. In this manner the entire fastener or any predetermined portion thereof can be made in a positive manner to assume a substantially arcuate shape within the material. The spring 95 is employed to provide against any possible undesirable shock which the plunger 91 may impart to theabutment when it comes into engagement therewith.

It is of course apparent that the fastener 9B, being made of relatively thin wire, will not be able to cause an appreciable retraction of the abutment if the spring 95 is made sufficiently strong, whereas the plunger 91 being generally made of heavy steel or some other sturdy material, will be able to cause such a retraction.'

To obtain even agreater bending of the penetrating fastener and a more positive defiection thereof, the form of my invention illustratedin Figures 17, 18. and 19 may be effectively employed. The general construction of the fastener housing 53a, plunger 41a, and framework 58 and associated partsare substantially similar to that shown in Figures 6 to 14 inclusive. However, employed in conjunction with plunger 41a is the anvil 99 adapted to underly the Work |00 being stapled. In this case, the lower. portion |0| of the fastener will be clenched upwardly by the anvil before the top head |02 is completely formed by a collapse thereof under the influence of plunger 41a. The anvil also serves to support the fastener during the formation of head |02. It is preferable that the underlying anvil be provided with a downwardly. tapering receiving recess I03 to facilitate the formation of the bottom clench. With this construction, a stack of inclined straight wire fasteners of the type above described can hence be operatively driven to obtain a top and bottom clench effective for use not only in sealing containers, but also adapted for ofiice stapling and tagging operations.

It is of course understood that other additional forms and modifications of the apparatus andadaptations of the method constitutingthis in- I vention can be employed beyond and in addition to those hereinabove described, all within the scope of the appended claims.

What I claim is:

1. In a machine for driving a single-pronged fastener, a plunger operatively engageable with the fastener, and an inclined support for supporting the plunger and fastener and directing them at an inclination with respect to the surface of the work' being fastened, said support being wholly removed and in spaced relation to the work whereby a partially driven ,fastener that has passed -beyond said support will contain a laterally unsupported inclined column extending out of the work and in the path of the plunger, the plunger during its operative movement being at all times substantially parallel to the fastener and being engagable with said column to cause a collapse thereof' against the work.

2. Ina machine for driving a single-pronged fastener, a plunger operatively engagable with the fastener, an inclined retractible support for suppotring the plunger and fastener and directing them during a predetermined portion of the stroke at an inclination with respect to the surface, of the work being fastened, said support beingr wholly removed from and in spaced relation to the work, and means for retracting said support before the compeltion of the driving stroke wherebythe partially driven fastener will contain a laterally unsupported inclined column extending out of the work and in the path of the plunger, the plunger being movable with its said support during the retraction thereof and being engageable during its continued operative movement with said column to cause a collapse thereof against the work, the plunger being at all times substantially parallel to the fastener.

3. In a machine for driving a single pronged fastener from a stack of fasteners inclined with respect to the surface of the work being fastened, a magazine for operatively supporting said stack, an inclined plunger operatively engageable. with the top of the foremost fastener, and guiding means having an inclined surface adjacent the front surface of the plunger and adapted to cooperate with the second fastener in the stack for directing the plunger and fastener at an inclination with respect to the surface of the work, said plunger and said guiding means surface being disposed substantially parallel to the fasteners, the said magazine being slidably engageable with the plunger and in spaced relation to the Work whereby a partially driven fastener that had passed out of engagement with the magazine will contain a laterally unsupported inclined combination according .to claim 2, the said retractible support comprising a housing for the fastenersand containing an open forward end the peripheral edge of which is in the plane of the front surface of the second fastener of said .stack whereby the plunger during its operative movement will vslidably engage andl be supported by said peripheral edge of the support and the said second fastener.

5. In a machine for driving a single pronged fastener from a stack o'f inclined fasteners, a framework, an inclined plunger channel, a magazine for operatively supporting said stack and containing an open forward end through which the fasteners are operatively fed, inclined guiding means extending rearwardly from the front portion of said framework and engageable with the foremost fastener of said stack, yieldable means for urging said stack of fasteners towards the channel and into engagement with said guiding means, and inclined plunger operativelyengageable with the top of thek foremost fastener and movable within said channel during its operative stroke, the forward portion of said magazine being in supporting engagement with said plunger, said magazine being in spaced relation with the work being fastened whereby a partialment with the magazine will contain a laterally unsupported inclined column extending out of the work and in the path of the plunger, the plunger during its operative movement being engageable with said column to cause a collapse thereof against the work.

6. In a machine of the class described, the combination according to claim 5, the said magazine being retractible rearwardly, and means for retracting said support before; the completion of the driving stroke whereby a partially driven fastener will contain a laterally unsupported inclined column extending out of the work and in the path of the plunger, the plunger being movable with said magazine during the retraction thereof and being engageable during its continued operative movement with said column to cause a collapse thereof against the work.

'7. In a machine of the class described, the combination according to claim 1 wherein the plunger is provided with a tip for operative engagement with the top edge of the fastener during the driving stroke, said tip being substantially parallel to the work and thicker than the fastener and extending forwardly beyond the top edge thereof whereby it will engage the underlying upwardly extending inclined portion of the fastener upon the completion of the stroke to cause a collapse thereof against the work.

8. In a-machine of the class` described, the combination according to claim 1 wherein the plunger is provided with a tip for operative engagement with the top edge of the fastener during the driving stroke, said tip being substantially parallel to the work and extending forwardly beyondjthe top edge-thereof a distance l no less .than the height of the support above the work whereby it will engage substantially the entire underlying upwardly extending inclined portion of the fastener upon the completion of the stroke to cause a collapse thereof against plunger and`fastener anddirecting them at an the work.

9. In a machine for driving a straight singlepronged fastener, a plunger having a pivotally mounted tip operatively engageable with the top of the fastener and extending therebeyond, and an inclined support for slidably supporting the inclination to the surface of the work lbeing fastened, said support being in spaced relation to the work whereby a partially driven fastener that had passed beyond said support will contain a laterally unsupported inclined Ycolumn extending out of the work and in the path of the plunger, the said tip being pivotally movable during the operative movement of the plunger to a path subwith said column to cause a collapse thereof against the work, the plunger being movable in the direction of the inclination of the support.

10. In a machine for driving a straight singlepronged fastened, a plunger having a pivotally mounted tip operatively engageable with the top of the fastener and extending therebeyond, an

` inclined support for supporting the plunger fastener and directing them at an inclination tothe surface of the work being fastened, said support being in spaced relation tothe work whereby a partially driven fastener that had passed beyond said support will contain a laterally unsupported inclined column extending out of the work and in the path of the plunger, and an abutment ly driven fastener that had passed out of engagestantially normal to the work and engageablespaced from lsaid. support for engaging the said tip and diverting it to a path substantially normal to the work whereby it will engage said column during the operative movement of the plunger to cause a collapse of the columnagainst the work.

11. In a machine for driving a single-pronged fastener, an inclined plunger operatively engage'- able with the top of the fastener, an abutment at the base of the machine, yieldable means holding said abutment in predetermined normal position and inclined guiding means in spaced relation to the work being fastened for directing the plunger and fastener at an inclination with respect to the surface of the work Vand towards said abutment when in its normal position whereby the fastener will be diverted from its path as it encounters the abutment and curled into the work.

12. In a machine for driving a single-pronged fastener, a plunger operatively engageable with the fastened, and an inclined support for supporting the plunger and fastener and directing them at an inclination to the surface of the work being fastened, said support being in spaced relation to the work whereby a partially driven fastener that had passed beyond said support will contain a laterally unsupported inclined column extending out of the work and in the path'of the plunger, the base of the plunger containing a projection and being engageable with said column to cause a collapse thereof against the work and a bending into the work of the part of the fastener engaged by said projection.

13. In a machine for driving a straight singlepronged fastened, a plunger having a tip operatively engageable with the top of the fastener and extending therebeyond, an inclined support for supporting the plunger and fastener and directing them at an inclination to the surface of the work being fastened during a portion of the operative stroke of the plunger, and an anvil underlying the work to receive the penetrating portion of the driven fastener an'd deflect said portion against the undersurface of the work, the said support being in spaced relation to the work whereby a partially driven fastener out of engagement with said support will contain a laterally 'unsupported inclined column extending out of the work and in the path of the plunger, the plunger during its operative movement being en*- gageable with said column to cause a collapse thereof against the work, the said anvil being adapted to cooperate with the work in supporting the fastener` as the said column is being collapsed against the Work.

14. In a method of driving a straight singlepronged fastener, the steps of applying driving pressure upon the top of the fastener along an inclined path in the direction of the work being fastened until a predetermined portion of the fastener penetrates the work whereby an inclined column is left extending out of the work. sup-

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