US2914983A - Explosively driven fastener having axially collapsible radially expandable locking sleeve - Google Patents

Description

Dec. 1, 1959 R. J. KOPF ETAL 2,914,983

EXPLOSIVELY DRIVEN FASTENER HAVING AXIALLY COLLAPSIBLE RADIALLY EXPANDABLE LOCKING SLEEVE Filed Dec. 9. 1953 l 3 Sheets-Sheet 1 22 v i6 2O INVENToRs RowLA/vo .1. Kopf YALBERT 7T MASTERS ATTORNEY Dec. 1, 1959 KOPF E1' L 2,914,983

EXPLOSIVELY DRIVEN FASTENER HAVING A'XIALLY COLLAPSIBLE RVADIALLY EXPANDABLE LOCKING SLEEVE v Filed nec. 9, 1953 s sheets-sheet 2 INVENTORS KOP F ROWLAND J.

ALBERT T. MASTERS BYV ATTORNEY Decl, 1959 R. J. KOPF rs1-AL v EXPLOSIVELY DRIVEN FASTENER HAVING XIALLY COLLAPSIBLE RADIALLY EXPANDABLE LOCKING sLEEvE 3 Sheets-Sheet 3 Filed Dec. 9. 1955 XBX n 26| 'cyg /z A e2 vs al eo INVENTUM ROWLAND J. KOPF ALBERT 7'. MASTERS United States Patent EXPLOSIVELY DRIVEN FASTENER HAVING AXIALLY COLLAPSBLE RADIALLY EX- PANDABLE LOCKING SLEEVE Rowland J. Kopf, Rocky River, and Albert T. Masters, Fairview Park, Ghio, assignornby4 mesne assignments, to Olin MathiesonChemical Corporation, a corporation of Virginia Application December 9, 1953, Serial No. 397,198

4 Claims. (Cl. 85-2;4)

This invention relates to fasteners and more particularly to a stud orv bolt of the. type whichis to be driven either through or into wood, metal plate, masonry, concrete or other materials of construction by means of an explosive poweredtool.

In the use of' explosive driven fasteners it is often necessary todrive. them into materials or parts of rnaterials not quite capablev of giving a satisfactory hold upon this type of fastener as a result of penetration into the bodyof the material. Examples of` such materials, characterized by a certain softness, tendency to spall or splinter, are certain types of wood, soft aggregate concrete, softV brick or masonry, macadam and even mild steel. The usual explosive driven stud of the type shown in U.S. Patent No. 1,365,870 will not hold under the least appreciable pull in some instances in such materials; and often the very act of screwing a nut down on the threaded end of the fastener willpull it out..

Therefore an object of this invention is the provision of a fastener capable of not only being driven explosively but of also having an improved holding power ineven those soft materials heretofore'deemed unsuited for explosive driven fasteners.

Another object is'provision of an explosiveI drivenfastener having enhancedholding power inlanytypeof material with which such fasteners have,I been heretofore found usable so` as to be4 capable of sustaining: heavier loads.

In accordance with this inventionlhere is provided a fastener adapted not only for facilitating` projectionl of therfastenerwithout interference into materials under the action of an explosive but also for enabling` subsequent better anchoring of the fastener. Accordingly afstudsis providedhaving a-suitably pointed front'end'for penetratingthe material into whichfit is to be-firedandalong., the

shank of the stud back of thepoint aportionfadapted forradial enlargement preferably by expansion or-otherV deformation.

This portion comprisesa sleeve member theV wall of which is deformable at a desired poi-nt southat the wall ofthe sleeve at such point can be expanded-radially out,- wardly after the fastener or stud has been-driven bymeans of an explosive operated tool intothe mate-rial` of some object on which it is desiredto `fastener support other objects. Expansion of the-sleeve is preferably i accomplished by compression axially between the point or head of the stud and a compression or screw-down member or isbrought about with the aid of a wedge.` Infanyevent" the forepart of the shank: of the studfis so 'constructed` as to provide a piercingy form anda shoulderfdesigned to act as an abutment-fortune end` of the expandable portion and-as a protecting cover for the sleeveduring penetration ofthe stud upon itsl being tired. It has beenfound that by providing 4on the` stud a piercingfrhead; or: point having the outermost part of its diameter' not less `than and preferably slightly-inexcessof the outside diameter of the expandable sleeve at least at and ahead of the deformable section of the sleeve, the stud may be i ce driven very much like the ordinary explosive driven stud without interference from and disruption of the expandable portion.

The aforementioned objects as well as other objects, advantages, and the specific nature of the invention will be better understood from the following description of the specific preferred and illustrative embodiments of the invention shown in the accompanying drawing in which:

Figure 1 is an elevational side View of one embodiment of the article of this invention;

Figure 2 is a cross sectional view of the embodiment of Figure l taken on line II-II of Figure 1;

Figure 3 is an elevational rear view of the embodiment of Figure l;

Figure 4 is a sectional view taken on line IV-IV of. Figure 1;

Figure 5 is a view partially in cross section showing a modified form of compression member;

Figure 6 is an elevational side view of another'embodiment;

Figure 7 is an elevational side view of a third embodiment having various modifications in the point and sleeve, part of which is broken away for clarity;

Figure 8 is an elevational side view of the fastener of Figure 7 after it has been driven and expanded for full anchorage inthe surrounding material.

Figure 9 is an elevational side View of a fourth embodiment with apart broken away for clarity;

Figure 10 is an elevational side view of a fifth embodiment, part of which is also shown broken away, employing a wedge;

Figure 11 is` an elevational side` view of still another embodiment of this invention shown driven, expanded and serving to attach a channel, for example;

Figure 12 is an elevational side view of another embodiment also'partly broken away;

nose; Zand a screw-down member 5 threadedly carriedv onthe rear endportion` 4. Sleeve 3 is longitudinally slotted to providea plurality off slots S, terminating short: of the, frontend of the sleeve3. These slots form a weakened orexpandable regionpreferably in the forepart of the sleeve 3 inasmuch as the material of the object' driven' into is`-r least disrupted" and better suited for anchorage thanparts `located nearer the surface driven into. A's shown` in Figure 3, the' screw-down member 5 is adapted toibe turned down on the threaded part 4 and for thispurpose is provided with diametrically opposedl flats Gifor engagement with vsome turning instrument as a` wrench. In this embodiment it is to be noted that, the body'or posterior section 7 of the conical point 2 has a diameter in excess of the outside diameter ofthe sleeve 3l which leaves a stepped Vabutment 9ybetween section 7 and"sl`eeve 3 for the purpose oflpreventingl seizing of the, forepart of" sleeve 3 during firing ,of the fastener and .re- Sultant undesirable disruptionatthe slots 8.

In operation the fastener of this embodiment is explo- Sivelyf driven in, the, usual manner and afterward the screw-down member or round nut 5 is lturned down to compresstsleeve 3: between-.nut `5 and stepped abutment 9- and cause: the. sleeve to.-expandradial 'at the; slots; 8` until further resistance to turning indicatesV thatftanchor age has been achieved. There is left protruding the threaded rear end 4 for attachment of some object and load to the fastener after it has been so anchored. Under circumstances where the full length of threaded section 4 is desired, the nut 5 may be withdrawn after it has served its function of causing enlargement of the sleeve. In this embodiment frictional forces between the head 2 and the target material are depended upon to prevent turning of the shank 1 and the threaded rear end 4 while nut 5 is being turned down.

Another way of obtaining a fully or longer threaded rear end on the fastener is to provide it with the screwdown member of Figure 5 in place of nut 5 of the foregoing embodiment. This special screw-down is of the same external diameter as sleeve 3 but has at its front face a recess 11 of the same diameter as threaded rear end 4 and internally threaded at 12 to a sui'licient depth to permit turning down of the threads 12 on the threaded rear end 4 for adequate compression and expansion of sleeve 3. The rear part of this special nut is shown sol-id except for the diametral hole 14 provided for permitting insertion of a rod for turning to compress the sleeve. However it will be understood that the rear face of part 10 may instead be provided with a recess in the form of a socket or may be cut to have a square or hexagonal end engageable with a socket head wrench. In any event the form of screw-down illustrated in Figure 5 has external threads 13 for reception of means such as a nut for securing objects to the fastener.

rThe embodiment of Figure 6 has back of the conical nose portion 15 and the cylindrical nose portion 22, a sleeve 16 having helical slots 21 instead of longitudinal slots for easier expansion. Back of sleeve 16 is a cylindrical screw-down member 17 screw threadedly carried on the rear end portion 18 of the fastener shank. Both the rear end portion 18 of the shank of the fastener and the member 17 are transversely perforated. Hole 19 in 18 is for connection with a tool which will be used to prevent turning of the shank of the stud while hole 20 in 17 isl for engagement with a wrench or the like used to operate the screw-down member 17. It will be appreciated that this embodiment has particular utility where greater torque is desired to severely deform the sleeve 16 at the slots 21 for maximum expansion in material which provides very little frictional resistance to undesired rotation of the nose portions 15 and 22 during turning down of member 17 under such torque.

The sleeve 16 of the embodiment of Figure 6 is further characterized by an outside diameter a large part of which is substantially identical with the diameter of the posterior cylindrical part 22 of the nose. However, at least the front edge of the sleeve is provided with a bevel at 23 which may in some cases be extended as far back as the rearmost part of the slots 21 so as to avoid inadvertent expansion of the sleeve 16 when it is undergoing penetration by explosive power.

The embodiment of Figure 7 also consists of an inner body or shank 24 the front of which is provided With an enlarged pointed head 25 and the rear end portion 26 which is screw threaded for reception of the compression member 27. About the intermediate portion of the shank there is expandable sleeve 28 all of the tubular wall of which, except for a minor portion 29 at the rear and a still smaller connecting band 30 at the front, is Weakened by helical slots 31 formed therein for obtaining maX- imum radial enlargement over an extended depth of the penetrated object with ease. It is to be further observed that the wall thickness of the sleeve 28 is at a minimum over all and tapers from least thickness at the connecting band 30 to a greater thickness at the unslotted section 29 where the outside diameter is not less than the maximum diameter of the nose portion and may exceed it slightly. The embodiment of Figure 7 is further characterized by a nose portion 25 having back of the tapered point 32 a cylindrical section 33 of greater diameter than part 32 and circumferentially serrated or longitudinally knurled so as to provide better resistance against rotation of the shank 24 during turning of the compression nut 27 than is obtainable by friction alone. Thus after the fastener illustrated in Figure 7 has been ired, the nut 27 may be turned down to cause sleeve 28 to mushroom at the slots 31 and make the enlargement 34 which anchors the fastener in the material 35 as shown in Figure 8 while serrations 33 hold the shank against turning and obviate the need for holding the protruding rear end portion 26.

In the embodiment of Figure 9 the inner body or shank of the fastener is provided at its ends with penetrating head 36 and threaded rear end portion 37. The expansion member 38 and the compression members 39 are modified. Member 38 is a shortened sleeve having slots 40, either longitudinal or helical although the former are shown, extending from one end of member 38 to nearly the other end where only a connecting band 41 is left. Member 39 is a sort of extended sleeve internally threaded at 42 adjacent the rear end of the bore of 39 for screw threaded engagement with the male threaded portion 37 of the shank. The rear edge of member 39 contains notches or castellations 43 for engaging with a turning tool such as a spannei wrench for screwing member 39 down to compress member 38 between the rear end of head 36 and the front end of 39 and cause expansion of 38 at the slots 40. This embodiment is adapted for turning compression member 39 down so as not to protrude above the surface penetrated by the fastener where it is desired that only threaded portion 37, all of it, protrude for connection and full usage. It also has the advantage of permitting the expandable section to be made of a soft material such as soft steel while all of the other and particularly the compressive force transmitting parts may be made of a strong hard steel.

'Fhe embodiment of Figure 10 has an inner body portion in the form of a solid cylindrical shank 44 with a smooth penetrating head 45 at one end and a threaded portion 46 at the rear end pierced by a diametral hole 47. Surrounding the shank 44, except for the head 45 and the rear end 46, is a sleeve 48 having a circular bore to permit both longitudinal and rotational motion between the shank and the sleeve, an expandable front part with slots 49 which run from and intersect with the front face of the sleeve #and having longitudinal serrations 50, i.e. grooves, fins or both, about the remainder thereof. Adjacent and encircling the head 45 there is a wedge portion 51 for operative engagement with the elongated sectors or ngers formed at the front of sleeve 48 by slots 49 for causing expansion of the sleeve as the wedge 51 is forced into the slotted section of sleeve 48 by the act of screwing the shank 46 backwardly through sleeve 48 with application of torque by means of a suitable instrumentality inserted at hole 47. It is to be observed that serrations 50 on sleeve 48 hold the sleeve against rotation thus permitting turning of the shank with respect to the sleeve. This embodiment is peculiarly suited for use where the head is free to move longitudinally as well as rotationally. Such situation occurs where the head even with serrations will not hold against rotation dependably as where the head passes entirely through the supporting object.

The embodiment of Figure 1l, shown driven through part of an upright supporting object 52 with a channel 53 supported thereon and held by means of a nut 54 on rear end 55, differs from that of Figure 10 in respects which adapt it for use where the head 56 provides no hold at all as where it is entirely free from the material into which -the fastener was fired and which will offer little resistance to rotation of the sleeve 57. The forepart of the sleeve, as in the previous embodiment, is provided with end slots 58 which permit expansion of the front of sleeve 57 coacting with the wedge 59 adjacent the exposed head 56 so as to positively anchor the fastener. The rear periphery of sleeve 57 is in any event provided with 'a suitable number of notches 60 for connection with Spanner tool in order to either turn or hold the sleeve during applicationof opposite torques to sleeve 57'and the shank of the fastener at notches 60 and hole 61 respectively after the fastener has been driven explosively.

The embodiment of Figure 12, likethe embodiments of Figures 1.0and 11, is also'characterized by employment of awedge to accomplish expansion. The-fastener shank 62 has a penetrating head-63 having serrated section 64 and has a threaded rear end portion 65. On the shank is an expansion sleeve 66 with elongated slots 67 intersecting the rear face of sleeve 66. Carried on the shank adjacent sleeve 66 is a screw down sleeve 68, the rearmost end of the bore of which is internally threaded for engagement with threaded rear section 65 and the front of which is conical and forms a wedge 69 for cooperation with the expandable slotted section of sleeve 66. Application of expansion force to the fastener of this embodiment occurs by way of the notches 70 in the rear edge of sleeve 68.

In Figure 13 there is illustrated a still further modication of the article of this invention wherein expansion s obtained by deformation of a relatively malleable or plastic element in the form of a sleeve or ring 71 of lead, synthetic or natural rubber, or of any suitable plastic such as polyethylene, for example, and the like carried about the shank 72 for compression between the penetrating head 73 and the compression sleeve section 74 also carried on shank 72. Although the deformable element 71 is shown unslotted, it will be understood that it may be slotted, if necessary, to even further enhance the expansion effect obtainable with this embodiment.

The fastener of Figure 14 also embodies the fundamental notion of this invention but is more suitable for use with installations wherein the fastener is driven through the supporting material so that both ends protrude and are accessible to the workman and for attachment of loads to both ends. This embodiment has a shank 75, a special head portion 76 for facilitating penetration and also the subsequent provision of a load holding means on the shank to better resist withdrawal of the fastener by a force or load applied through the threaded front end 78 or the rear end part 77 integral with shank 75. On the shank there is the threaded anterior protrusion 78 which engages with part of the internal threads 79 in the nose portion 76. Slidably mounted on shank 75 between head 76 and rear end 77 is an expandable sleeve 80 having slots 81. Expansion is obtained by compressing sleeve 80 by screwing in head 76 relative to the shaft 79 and its threaded rear portion 77. Application of torque to this fastener is facilitated by provision of a spline 82 or the like on head 76 and by provision of the socket recess 83 or the like on the rear end 77. Thus after projection this fastener is grasped at both ends by suitable tools and torque is applied until the sleeve 80 is compressed sufciently to work an expansion at the slots 81 thereby anchoring the fastener. While the rear end 77 is shown as an enlarged section integral with shaft 75, it will be appreciated that the rear end 77 may be a separate nut threaded upon shaft 75 similarly to the separable nut-like head 76 and that the sleeve 75 may be compressed between two nuts at opposite ends of the shank or body 75.

In all the foregoing embodiments the actuating sleeve or screw-down member, such as member 6 of Figures l to 4, also serves as a means of retaining the expansion member, such as member 3 upon the shank 1, during handling of the fastener before driving as Well as during driving of the fastener. In a sense, therefore, another modification of the fastener of this invention is attained by elimination of the screw-down member and replacement thereof with an expansion member retaining means such as a protruding circumferential upset or enlargement or even a burr formed on the shank back of the expansion member after assembly of the expansion member on the shank in such a way as to permit compressive force to be applied to the expansion member. With this` modification expansion. may be worked either` by Iblows appliedV through a Spanner sleeveinserted over the rear end ofthe shank or by a screw jack tool applied over fands engaging with the threaded rear end of the fastener. It will be appreciated, however, that the inclusion. of thecompression or screw down member is preferredinasmuch this forms a shield against the explosion force applied back of this type of fastening device and prevents undesired enlargement of the fastener' during the driving operation by such force of explosion acting upon the deformable member. It will also be appreciated that as a further modication the rear end portion of certain of the foregoing embodiments may be of enlarged diameter so as to operate per se as an object holding or securing means in the nature of a nail head.

Since other combinations of the various features de- V scribed herein and even other embodiments of this invention may occur to those skilled in the art, it is to be further understood that the foregoing is intended by Way of illustration of preferred embodiments and not as a limitation of the scope of the present invention except as set forth in the appended claims.

What is claimed is:

1. A fastener adapted to be driven from an explosive operated tool comprising an elongated cylindrical shank one end of which is threaded, a pointed piercing head portion of the projectile type described on the other end of said shank for penetrating the surface of a supporting object under the force of an explosive charge, a compression member screw threadedly carried on the first end of said shank and a tubular sleeve surrounding the intermediate.. portion of said shank between said head portion and compression member, said intermediate portion of the shank having a diameter less than the maximum diameter of said head and forming with the head at the junction therewith an annular shoulder, said sleeve `having a diameter not in excess of the maximum diameter of said head and being provided with longitudinally extending slots whereby the slotted portion is weakened and is adapted for expansion after the driving operation by turning of the compression member down against the sleeve in abutment with said shoulder.

2. A fastener adapted to be driven from an explosive operated tool comprising an elongated cylindrical shank one end of which is threaded, a pointed piercing head portion of the projectile type described on the other end of said shank for penetrating the surface of a supporting object under the force of an explosive charge, a compression member screw threadedly carried on the first end of said shank and a tubular sleeve surrounding the intermediate portion of said shank between said head portion and compression member, said intermediate portion of the shank having a diameter less than the maximum diameter of said head and forming with the head at lthe junction therewith an annular shoulder, said sleeve having a diameter not in excess of the maximum diam- -eter of said head and being longitudinally slotted intermediate the ends of said sleeve whereby the slotted por tion is weakened and is adapted for expansion after the driving operation by turning of the compression member down against the sleeve in abutment with said shoulder. 3. The fastener of claim 1 wherein the slots are helical. 4. The fastener of claim 2 wherein the slots are adjacent the front end of the sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 1,164,322 vearman Dec. 14, 1915 1,224,926 Hindmarsh May 8, 1917 1,232,274 Gay July 3, 1917 1,342,201 Beckwith June l, 1920 (Other references on following page) 8 Catlin Dec. 22, *1953 Murphy May 8, 1956'l FOREIGN PATENTS Great Britain 1938 Great Britain Feb. 25, 1948 Great Britain Nov. 24, 1948 Australia July 21, 1950

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