Fastener Assemblage

Abstract

An assemblage of collated fasteners is provided for use in a powered fastener-driving tool. The fasteners are provided with elongated shanks arranged in spaced substantially parallel relation. A plurality of elongated flexible strips engage the fastener shanks and retain same in predetermined spaced relation. Each strip includes sleeve portions encompassing the shanks of the fasteners, and thin web portions interconnecting adjoining sleeve portions. Each web portion has formed therein, an elongated relatively thick reinforcing rib spanning the distance between adjoining sleeve portions. The ribs of one strip are less resistant to forces applied transversely to the accommodated shanks causing same to move closer together than the remaining strip of reinforcing ribs. The ribs cooperate with the sleeve and web portions to provide controlled fracturing across the web portions connecting the endmost fastener and next-in-line fastener, when the endmost fastener is driven by the tool into a workpiece.

Description

BACKGROUND OF THE INVENTION

In many types of pneumatically, or electrically powered fastener-driving tools it is customary for the tools to be loaded with sticks of collated fasteners. The length of the stick will depend upon the type and size of the tool and fasteners being utilized. The sticks, in some instances, are relatively stiff with the fasteners thereof normally oriented in a spaced, substantially parallel, coplanar relation. In other instances, the collated fasteners are spiral-wound to form a cartridge. With either package of collated fasteners, the endmost fastener of the collated fasteners is successively fed automatically by a feed mechanism incorporated on the tool to a firing station whereupon it is then driven by the tool into a workpiece. Collating of the fasteners greatly facilitates loading and reloading of the tool; however, notwithstanding this fact, the fasteners frequently became jammed in the feed mechanism or the firing chamber of the tool, or the driven fastener does not break cleanly from the remaining collated fasteners and thus, cause fragments of the assemblage to be carried by the driven fastener into the workpiece and interfere with the proper seating of the fastener in said workpiece. Furthermore, in certain sticks of collated fasteners, accidental fragmenting of the sticks occurred even when subjected to normal handling and thus, seriously impeded loading and reloading of the tool.

In still other prior packages of collated fasteners, the material utilized to collate the fasteners would become brittle and when the endmost fastener was driven by the tool into the workpiece, said collating material would fracture into a multitude of small particles which would be expelled rapidly outwardly in random directions thereby becoming hazardous to the person using the tool.

SUMMARY OF THE INVENTION

Thus, it is an object of this invention to provide a fastener assemblage which enables collated fasteners to be packaged in various forms such as, for example, elongated sticks or spiral-wound cartridges.

It is a further object of this invention to provide a fastener assemblage which enables the endmost fastener to be separated from the next-in-line collated fastener along a controlled line of fracture and thus, avoid jamming of the fasteners within the fastener-driving tool.

It is a still further object of this invention to provide an assemblage of collated fasteners wherein bunching or corrugating together of the fasteners thereof is avoided while said fasteners are being automatically fed through the fastener-driving tool.

It is a still further object of this invention to provide an assemblage which is adapted to accommodate a variety of fasteners.

It is a still further object of this invention to provide a fastener assemblage which greatly facilitates loading and reloading of a powered fastener-driving tool.

Further and additional objects will appear from the description, accompanying drawings, and appended claims.

In accordance with one embodiment of the invention a fastener assemblage is pr vided which is adapted for use in a powered fastener-driving tool. The assemblage includes a plurality of elongated fasteners arranged in spaced, substantially parallel relation. A plurality of elongated flexible strips are provided which extend angularly of the fasteners and interconnect and retain said fasteners in said spaced relation. Each strip has a plurality of sleeve portions which snugly accommodate the shanks of the fasteners and a plurality of thin web portions which interconnect adjoining sleeve portions.

Each web portion includes an elongated reinforcing rib which spans the distance between the adjoining sleeve portions. The ribs of the strip, disposed closest to the trailing ends of the interconnected fasteners, are angularly disposed relative to the longitudinal axis of the strip and thus, effect controlled fracturing across the web portion intermediate the endmost fastener and the next-in-line fastener when said endmost fastener is driven by the tool into the workpiece.

DESCRIPTION

For a more complete understanding of the invention reference should be made to the drawing wherein:

FIG. 1 is a fragmentary vertical sectional view of one form of the improved fastener assemblage shown disposed in the fastener feed assembly of a powered fastener-driving tool and with the endmost fastener bing driven into a work piece.

FIG. 2 is an enlarged fragmentary side elevational view of portions of the shanks of collated fasteners comprising the fastener assemblage shown in FIG. 1.

FIG. 3 is similar to FIG. 2, but showing the left hand fastener being driven in the direction of the arrows relative to the other fastener which remains in a relatively fixed position.

FIGS. 4 and 5 are sectional views taken, respectively, along lines 4--4 and 5--5 of FIG. 2.

Referring now to the drawing and more particularly to FIG. 1, one form of the improved fastener assemblage 10 is shown disposed within a guideway 11, the latter forming a part of the feed assembly of a pneumatically, or electrically powered fastener-driving tool 12. The guideway 11 terminates at a firing station 13 formed in the nose piece 14 of the tool. The station 13 is adapted to receive the endmost fastener A of the assemblage 10. When the fastener A is in position within station 13, it is engaged by the reciprocating driver blade or rod 15 of the tool and is caused to be severed from the assemblage and expelled out the bottom of the nose piece 14 and into a workpiece 16. The guideway 11, firing station 13, nose piece 14, and driver blade 15, are of conventional design and form no part of the instant invention to be hereafter described. The guideway 11 is provided with a suitable fastener-feeding mechanism, not shown, which works in cooperation with the movement of the driver blade 15 to effect automatic feeding of the endmost fastener of the assemblage into the firing station 13 as the driver blade moves to a retracted position.

When utilizing collated fasteners in a powered driving tool, it is essential that the fasteners move in a controlled, intermittent manner through the guideway 11 toward the firing station and not become jammed either in the guideway or the firing station. Furthermore, when the endmost fastener A is engaged by the driver blade 15, as seen in FIG. 1, there should be a clean break away from the remaining collated fasteners of the assemblage, so that no obstruction will remain which will interfere with the proper positioning of the next fastener in the firing station. In addition, whatever fragment of the assemblage, which might remain attached to the driven fastener, must in no way impede the penetration of the fastener into the workpiece or cause the fragment to shatter into small particles while the fastener is penetrating the workpiece which would rapidly propel the particles outwardly creating a hazardous condition for the user of the tool. Lastly, when the endmost fastener breaks away from the assemblage by reason of being driven by the driver blade, the driven fastener must not cause the remaining endmost fastener to assume an askewed position in the guideway and thereby interfere with the feeding of the fastener into the firing station.

The fastener assemblage 10, herein disclosed, meets the afore-noted requisites and consists of a plurality of collated fasteners 17 which may be roundheaded nails, T-headed nails, screws, brads, etc; however, for purposes of facilitating understanding of the invention, the fasteners 17 will be described and illustrated as roundheaded nails. Each nail 17 is of conventional design and has an elongated shank 17a with a pointed leading end 17b, and an enlarged head 17c formed at the trailing end of the shank. In the illustrated embodiment of the assemblage, the nails 17 are arranged in spaced, substantially parallel, coplanar relation with the enlarged heads thereof in stepped, abutting relation; that is to say, the head of each succeeding nail rests above the preceding head and the periphery of the lower head of the forwardly disposed nail tangentially engages the shank of the rearwardly disposed nail. Thus, the nail heads serve to properly space apart the trailing ends of the nail shanks. If desired, however, the nail heads may be arranged in laterally spaced, side-by-side relation.

Interconnecting the nail shanks of the assemblage are a pair of elongated, narrow strips 18 and 20 formed of a suitable thermoplastic material (e.g. polypropylene with a talcum additive). More than two strips may be utilized where the shanks to be collated are of substantial length. The longitudinal axes of the strips, in the illustrated embodiment, are angularly disposed relative to the shanks and conform substantially to the step angle of the heads. Where, however, the fastener heads are in-line spaced relation, the strips will be disposed at right angles to the fastener shanks. Strip 18 is disposed closest to the enlarged heads 17c of the nails.

Each strip includes a plurality of sleeve, or cagelike portions 21, which snugly embrace the nail shanks. Interconnecting the sleeve portions of the adjoining nails of the assemblage are very thin (e.g. 0.004 inch) web portions 22. Formed in the web portions 22 of strip 18 are relatively thick elongated reinforcing ribs 23, each of which extends substantially diagonally across the web portion, see FIG. 2. In the illustrated embodiment, one end 23a of the rib is integral with the upper periphery of sleeve portion 21 of the leading nail (A in FIG. 2) and the opposite end 23b of the rib is integral with the lower periphery of the sleeve portion of the next-in-line nail (B in FIG. 2). The angular disposition of rib 23, with respect to the nail shanks, will depend upon the spacing between the adjoining nails and the axial length of the sleeve portions 21. In certain instances, it is not essential that the ends of the rib 23 terminate at the upper and lower peripheries of the adjacent sleeve portions, as shown. By reason of the angular disposition of the ribs 23 in strip 18, the latter is less resistant to forces tending to bunch the nails together and also will be more prone to fracture when the leading nail is being driven by the driver blade 15. In all instances the thickness of the web portion is substantially less than the thickness of the wall of the sleeve portion and the cross-sectional thickness of the rib as well.

Strip 20 is the same construction as strip 18, except that the reinforcing rib 23', formed in each web portion 22' thereof, is disposed substantially parallel to, or coaxial with, the longitudinal axis of the strip. By reason of the in-line disposition of the rib 23' in strip 20, the latter is more resistant to compressive forces tending to bunch together successive nail shanks. The bunching together of the shanks is commonly referred to in the art as corrugating of the collated fasteners. Corrugating of the fasteners has heretofore frequently occurred in the magazine and feed assembly of high-speed driving tools and is a principal cause of the tool becoming jammed. Both ribs 23 and 23' permit lateral bending of the collated fasteners thereby enabling same to be coiled or spiral-wound to form a cartridge, not shown. Spiral-wound cartridges are commonly used in cylindrically-shaped canisters forming the magazines of certain types of power tools. Whatever way the collated fasteners are packaged, either as an elongated substantially straight stick which comprises a predetermined number of fasteners (e.g. 25 in number), or as a cartridge, the fasteners, while passing through the guideway 11, must assume a flat or coplanar relation, as shown in FIG. 1. Where the tool is adapted to receive only a stick of collated fasteners, one or more of said sticks are placed in a suitable track, which comprises a part of the guideway 11. On the other hand, where a cartridge of collated fasteners is disposed and is loaded into a cylindrical canister, the outer end portion of the cartridge is unwound a predetermined amount and positioned in the guideway 11. The rate the collated fasteners move through the guideway is dependent upon the rate at which the fasteners are driven into the workpiece.

Once the strips and fasteners have been assembled, an outer coating C may be applied over the strips and the adjacent portions of the shanks. Normally, the coating will extend to and include the leading ends 17b of the fasteners. Coating C serves a dual function: (a) it effectively holds, or bonds, the strips and fasteners in a relatively fixed relation, and (b) the coating substantially increases the holding strength of the fastener once it has been driven into the workpiece 16. A suitable coating for this purpose is identified by the trademark "SPOT-O-LON Z."

The assembly of the fasteners and strips, and the application of the coating thereon, may be readily accomplished by automatic high-speed equipment presently available.

FIGS. 2 and 3 illustrate how the endmost fastener A is readily severed from the next-in-line fastener B, when driven by the descending driver blade 15. As shank A moves downwardly relative to shank B, rib 23 of strip 18 moves in a counter-clockwise direction about end 23b; however, because nails A and B remain in substantially the same lateral spacing, rib 23 is subjected to compressive forces causing stresses to buildup therein. By reason of this force buildup, end 23b of the rib snaps or tears away from the sleeve portion embracing shank B upon the rib assuming a substantially perpendicular position relative to the fastener shanks, thereby causing a controlled break to occur between the web and the sleeve portion along a line of fracture X-X which is adjacent the sleeve portion of shank of fastener B and is substantially parallel to the axis of said shank. As rib 23 of strip 18 pivots about end 23b, the rib pushes against fastener B and causes same to remain within the guideway in an upright position until it is subsequently moved into the firing station 13 by the automatic feed mechanism of the tool. It has been found that fracturing of the rib and web portion of strip 18 precedes that of strip 20 and the fracturing of the latter also occurs substantially along the same line of fracture X-X, see FIG. 3.

It will be noted in FIGS. 1 and 3 that only a minute amount of the severed strips remains affixed to the endmost fastener and thus, in no way interferes with locating the fastener in the firing station 13. The sleeve portions and the strip fragments, which remain affixed to the shank of the driven fastener, will be readily stripped from the shank by the workpiece as the fastener penetrates the latter and the stripped fragment will not interfere with the fastener being driven into the workpiece the proper amount. The strips, as aforementioned, are formed of a suitable plastic material, which is semi-pliable, and thus, no minute particles or pieces of the stripped fragments will be formed which might be propelled outwardly causing injury to the user of the tool.

Thus, it will be seen that a fastener assemblage has been provided which effectively retains the collated fasteners in proper spaced relation while they are being successively fed to the firing station, permits controlled breaking of the web portion interconnecting the endmost fastener and the next-in-line fastener when the endmost fastener is being driven by the driver blade, and is possessed of sufficient stiffness to facilitate handling of a plurality of collated fasteners.

Claims

We claim:

1. An assemblage of collated fasteners for use in a fastener-driving tool wherein successive fasteners are driven by the tool from the assemblage into a workpiece, said assemblage comprising a plurality of fasteners, each fastener having an elongated shank provided with a leading end and a trailing end, the fastener shanks being disposed in spaced, substantially parallel relation; and a plurality of spaced elongated flexible strips angularly disposed relative to, and interconnecting said shanks, one strip being disposed closest to the shank trailing ends and a second strip being disposed closest to the shank leading ends; each strip including sleeve portions encompassing said shanks, web portions interconnecting adjoining sleeve portions, and an elongated reinforcing rib formed in each web portion and spanning the distance between adjoining sleeve portions and retaining same in predetermined spaced relation; the thickness of said web portions being less than the thickness of either said sleeve portion or said reinforcing rib; the reinforcing ribs of one strip being angularly disposed relative to the longitudinal axis thereof whereby the latter is less resistant to a force tending to move adjacent fastener shanks together than any other of said strips; each reinforcing rib of the one of said strips causing controlled fracturing of the web portion between an endmost fastener and the next-in-line fastener along a line substantially parallel to the fastener shank and adjacent the sleeve portion accommodating the next-in-line fastener when said endmost fastener is driven endwise by the tool into the workpiece.

2. The assemblage of claim 1 wherein the strip closest to the fastener heads is provided with the less resistant reinforcing ribs, each latter rib extending angularly rearwardly and downwardly from the sleeve portion accommodating the forwardly positioned fastener shank to the sleeve portion accommodating the next-in-line fastener shank; the reinforcing ribs of the strip closest to the leading ends of the shanks being substantially parallel to the longitudinal axis of the latter strip.

3. The assemblage of claim 2 including a coating applied to the exterior of said strips and the portions of the fastener shanks extending therefrom towards the leading ends to effect bonding between said strips and the fastener shanks; each of said strips being of thermoplastic material.