US1050345A - Expansion-bolt. - Google Patents

Description

J. R. CONRAD.

EXPANSION BOLT.

APPLIOATION FILED APB. 19, 1912.

1,050,345. Panendaan. 14, 1913.

W'nesseg: Ins/enfer:

sep/v R. Conrad.

" Uiviifnn s'rrtrns PATENT onirica.

JOSEPH R.' CONRAD, OF CHICAGO, ILLINOIS. ASSIGNOR, BY IESNE ASSGNMENTS, TO U: S. EXPANSIONBOLT CO., O' NEW YORK, N. Y., A CORPORATION OF NEW' YORK.

vsXPaNsioN-isoifi.

Specification of Letters-Patent.

Patented Jan. 14, 191

ppiicetion filed April 19, 1912. SerialNo. 691,839. i

.o all whom t may concern i Beit known that I, Josiirii R, CONRAD,

and security than has been heretofore posa citizen ofthe United States, residing at '.(l-'hicag0, in the county1 ot Coolr 'and State of Illinois,` have invented certain new and useful-Improvements i'n EXpansion-Bolts,

'of which t-hel following,r isi-a specification.

' This invention relates to bolts adaptedto lbe anchored lwithin a solid substance, and

particularly snc-h as are designed for attaching fixtures to brick or concrete walls. lThe principal objects of' the present in vention aretoconstruct an expansion bolt4 having but va parts, which may be anchored vwithin a wall with greater firmness sible; and toprodnce an expansion bolt .having shells adapted to be shifted or eX- The expansion bolt. of the present invention comprises essentiallyv three principal panded away from each other, which operation of shifting or expanding' shall be automaticalt'vv predetermined in such manner as not to"Wea-lren or iiiipairlthe wall at thepoint. where it is locked therein.

'Other' objects of my invention will appear from a detailed description .of the drawing and'l operation of the parts, as hereinafter set forth and'cl'aimed.

In the drawing, Figure 1 is a 'section of a wall and an expansion bolt tl'ierein showing the position of the holt and-shells before expansion has coinmencedg-Fig-2 isa simi lar View, but shows the 'positionl assumed by the parts of the expansion bolt at the coinnieneenient of tlie expanding operation; Fig. 3 is a similar view showing, however,

the position assui'nedbi-1 the part-s of the expansion bolt after the operation of ex'- pansion iscompleted; and Fig. is a View similar to Fig. 3 showingr 'the expansion bolt in elevation. l

. parts,"'viz., a pair .of segmental symn'retrical shells 5,.an expanding;1 .in'eiiiber G adapted to tr'Yello-ngitinJ-inally therein, and a bolt 7, upon which in snd e.\'pandiii(I member lis threaded, andfby whichxtlie 'saiu longitu dinal n ioveineiit is impart-ed thereto.' VThe I'shells illustrated in the drawing` are each forined on the interior with two lfaces at right angles to each other and inclined =from the inner to the outer .end thereof, and

are adapted-to present contactl faces for an v etpaiider in the form of a square nut which hears each of its sides against one of the r.lliis forni of construction is described at length and claimed in my pending application, Serial No. (322,109, filed April i9, ]911. lt should he understood that the 55 said inclined interior faces of the shells` present invention is equallyapljilicable in conil'iinatnin with any Aexpanding` nicniber and shells (littering materially inferossvsection.

At .the inner end. -of each voli' the shells,

there is foi-ined a. web 8^liaving a portion thereoteut away to provide in effect a pocket 9. The arrangement of each of the webs Sand cut-away portions therein. is such that, when the shellsl are placed together in position, a complete closure is provided at-.the inner end thereof with zthe tapered pocket formed in substantiallyY the axial line of the shells. The pocket. at the sidevhich faces the interior of the shells is of a suitable diameter to receive the inner er acting end of thebolt 7, andtapers inwardly in such a manner that 'upon ad vancenient of the bolt therein, the shells will of necessity be forcedapartat their inner ends as bv a wedge-action;

The exterior of theshells is'provided Wit-h i i a number of spirallv-fornied threads 10 u thereon adapted to effect a tightl and secure hold against-'the wall within which the exvpansion -bolt is anchored. Locking means when bent inwardly t-o embrace neck por'- tion 12 upon the other of said shells. A

flange 13 formed at the outer end of one of the shells Serves as a capV to cover'the edges of the hole within which the expansion' bolt is secured, as well vas to predetermine its proper longitudinal position therein. Y

In putting' into use the-expansion bolt `of the present invention. the steps and operations"in\'ol\ed are substantially as follows: The expansion bolt.. is A'first assembled hy in# serting` the bolt through the flanged' end of one ofl the 'shells and threadingr the nut. thereon. The other shell is then broughtinto proper registering position and -is locked with respect to its oo-acting shell by means of the bendahle lugs orined at' the. outer end'thereof. ,With the mit in eosiv which I am aware.

tion at the extreme inner end of the shells to permit of their lying close to one another the expansion bolt is then inserted into a hole of proper size which has been formed in ,the wall or ceilinowhere it is to be anchored. Rotation ot-J the holt is then commenced which will cause its acting end, to seat within the tapered pocket on the interior of the shells to apply a wedge pressure thereto. Inasmuch as the outer ends of the shells are held closely together by'means of the embrace of; the locking lugs, movement of the nut in that direction against the inclined faces of the shells cannot readily take place, with the result that the acting end of the bolt will be advanced farthen into the tapered pocket at the inner endvof the shells; this movement causes the `shells at their inner end to expand and bite into thematerial within which the expansion bolt is being anchored. It is'obvious after the acting end ofthe bolt has advanced a certain distance and has expanded the inner' ends of the shells against a constantly increasing pressure that further inward movement of the boltmust cease, and that resistance tothe travel of the nut being now less than that otl'ered to thelongitudinal movement of the bolt, the nut will be caused to travel out ward. y (See Fig. 2). During the longitudinal travel of the nu't to the position indicated in Fig. 3 the inner ends of the shells will be constantly maintained in expanded position, for the reason that/tire bolt coi1-` tinues to exert an end thrust against the inner end of the tapered pocket, thereby effectually preventingr any tendency of the shells to collapse at their inner ends. The limit of expansion will obviously be reached when the nut has advanced to the outer end of the shells, as shown in Fig. 3, which point can only be reachedafter sufficient expanding pressure'has been communicated to the outer end -of the shells to cause the locking lugs to release their holdV to permit of the shells shifting away from each other.

By the construction of an expansion bolt which operates substantially in the manner just described, I am enabledv to secure a hol-d within the hole more tight and secure than is possible with any other form of bolt of In order that. the outer edges of the hole may not be weakened or mutilated, beingobviously the partmost susceptibleto cruml'ilingr and chipping, it is eS- sential that the operation of expansion should take place initially at the inner end yof the holo. This I have accomplished by means of the acting end ol' the bolt which .is made to exert a wedge action` within the ta )cred pocket formed at the interior of the s tells, lt is not enough, however, that the expansion should be commenced at the inner end of the shells for the reason that greatest efticiency will result only when the whole ex- 4'other so as to facilitate their insertion withterior surface of the shells is made to grip and engage the interior of the hole within which the expansion bolt is anchored, thus guarding against possible slipping or slid 111g movement of the shells Within the hole.

As has just been explained, the' shells of the present invention are expanded` at their outer ends to attain the greatest locking efficiency, only after the inner ends thereof have first been firmly embedded against the sides of the hole. The successful operation ot' causing the expansionto take place in substantially the manner just described is assured throughthe agency of the locking lugs at the outer ends of the shells which by retarding the advancement of the nut causes the bolt to advance into the tapered pocket to expand first the inner ends of the shells.-

The pocket, as shown `in the drawing, is substantially in the form of a parabolic conoid and whenso shaped is admirablyI adapted for the purposes of this invention. lt will be noted that the acting end of the bolt must engage first with that portion .of the pocket where the sides taper only slightly, thereby conducing to the ready eX- pansion of the shells at the inne;` end. As the acting end of the bolt advances intothe pocket, however, the radius of the curve thereof decreases, with the result that increasing pressure is gradually brought upon the inner end ot the bolt to prevent its further ingress into the pocket. It is customar to form such bolts with their ends bevele as s hown in the drawing, so that the thrust of the bolt upon the faces of the pocket is not that ot' an edge so sharp as to mutilate either of the engaging parts, or to produce an undesirable amount of friction:

The lugs formed upon one of the shells adapted to embrace the other thereof for the purpose of effecting a releasable union therebetween operates not only in conjunction with the engaging action of the bolt in the tapered pocket at the inner end .of the shells to produce the novel expanding operation already explained, but serves as Well to lock the shells together in proper relation to each in the wall. It will be noted also that the neck portion of the shell which is embracedl bv the locking lugs is so formed as to pre-t vvent longitudinal movement` of one shellv with respect to the other, when embraced by the locking lugs. This is of particular importance in view of the fact that without ltheprovision of means to prevent' longi- ,tudinal movement of one shell with respect place 12'5 to the other expansion could not take at the inner end of the shells through the wedge action exerted by the acting end of the bolt.

Q' It will be observed that, although the expansion bolt of my invention is construct- Led-:so as-to expandupon a nove Aiprifn" i ple operation, and topresenticer a1 n .other `g-.to-increase expense or cioniplic'ation.

fpansion .of the shells may-be. ,of the ordinary standard pattern. -T'he means'also by @which the shells are relea'sa'bly held to- ,fgether, as well as the ca pfpiece'ui'ised, to predetermine .t-helongitudinal .position of the .stiell'sfwitliinjthe walls, and :to conceal the hfole therein, are formedintegral with the shells, thus' minimizing' the" numherof. pa'rts I ingl shells, each formed on its interior with adapted when rotated to advance its inner= longitudinally inclined faces, an,.exp ansion member within said shells 'adapted'. when tidvanced against said inclinednfaesto force said shells apart, awebformation attlie 1nner end of each of said Ashells having' a cutaway tapered portion'therein, a bolt in engagement with said expanslon member actingr end against'the tapered faces of said cut-away portion to forcethe inner enfls of said shells apart, and means for preventing; initial expansionof said shells at the outer ends thereof, siibstantiall';7 as described. Y

2. In an expansion bolt, a pair of co-act.v ing'shells, each formed on its interior withlongitudinally inclined faces, an expansion member within said shells adapted when advanced against said inclined faces to force Said shells apart, a web formation at the inner end of each of said .shells-.having a cut-away tapered portion therein, a bolt in engagement with' said expansion member adapted when rotated to advance its inner acting end against the tapered faces of said cut-away portion to force the inner ends of said shells apart, and means for preventing initial expansion of said shells at the outer ends'thercof, said means comprisingr a'pair of bendable lugs formed atthe outer end of one of said shells adapted to yieldingly embrace a. portion of the other of said shells,

Substantially as described.

3. In an expansion bolt, a pair of co-acting shells, each formed on its interior with longitudinally inclined faces, an expansion member within said shells adapted wheny featilres ofradvanta'ge and iniportance,.the i'e l1s not provided any additional part-s-,tend-` enut and bolt employed to'eflect theexf other pocket substantially the' cessary ,toft-he operation `of the -ex'p .nsionaeting'i'end against the taperediwalls ofsaid vpocket td force the inner 'ends of saidshelils apart,su`bstantially'as described.

4. ln anv expansion bolt, appair 'of comet- .in'g shells, each V formed onits interior with.

longitudinallyinclined faces, an'fexpansion member within'said'shells-adapted when adifaneed'against said inclined faces to force said shells apart, a web portion fatthe inner cndof each of 'said shells having a ciit-an-'a 'yY tapered portionA therein constituting when brought into registering po tion with .each forinof a .m 'int A"ivitli parabolic conoid, a b ol't in en,i;a",

said fexpanslon meinberfadapt'ed.when -rotated to -adi'fance'its actingiendzlagainst the tapered .portionof said pochette' force the tially as described.

- 5. 'ln an expans Vinner ends of saii'lsliellsgapart, and means "for ",preventingrV initial `expansi.o`n". ots vshell-s at the outer ends thereof' substan- '85 ing shells, each formed on its interior with longitudinally inclined faces, an expansion member wil liin said shells adapted. n'lien ad-l vanced Vagainst .said inclined faces to force said shells apart, a we.) adjacent the inner end of each of said shells, the facing walls of of said webs tapering toward the inner ends thereof, a bolt in engagement with said expansion member adapted when rctated to advance its inner acting end lie-- tween the tapering facing walls of said webs to force the inner ends of said shells apart, means for retardii'ig the advancement of said expansion member' toward the outer ends of said shells, said means serving also to maintain a fixed longitudinal -relationbetween said shells, substantial ly as described.

6. In an expansion bolt, a pair nico-actingshells, each formed on its vinterioiwith longitudinallyinclined faccs,-an expansion member within said shells adapted when ad- `vanccd against said inclined faces to force'- said shells apart, a web adjacent. the inner end of each of said shells, the facing. walls of each of said webs taperingr toward the in ner ends thereof, a. bolt in engagement with said expansion member, adapted when rotated to advance its inner acting end between said tapering faces -to force said inner ends of said shells apart, and means for retarding the advancement of said. expansion member within said shells to-z ward tlie outer ends thereof comprising a.. pair of lugs integrally torincilja-'illi one -of said shells and adapted to ieldinfrlv ern f Abrace i'iie vother thereof, said iiicans serving also to maintain a (ixcfl loiigiti-idina-l relation between lsaid shells, substantially as described..

7.. In an expansion bolt, a pair ofen-acting shells, each formed on its interior with longitiidii'ially inclined facesLan expansion meinbeirwithin said shells adapted when advanced against said inclined faces to force said shellsapart, a web adjacent the inner' end of each of said shells, the facing walls of each of said Webs tapering toward lthe inn'er ends thereof, a bolt/.in engagement with said expansion member, adapted when rotated to advance its inner acting end be-- tween said tapering -facesto force the inner ends of said shells apart, means for retarding the initial advancement of said'expansion member within said shells toward theouter ends thereof comprising alpair of lugs integrally formed with one ofsaid shells, and adapted to yieldingly embrace the other thereof, said means serving also to maintain a fixed longitudinal relation between said shells, and a flange member-secured to the outer end of one of said shells adapted to rest against the exterior surfaceof the an-v said`shells apart,. means for advancing said 30 Y expansion member agalnst sald inclined faces, means for expanding the inner ends of' said shells, and means for retarding the ad# vancement of said expansion member to permit initial expansion at the inner ends o said shells, substantially Aas described.

9. In an expanslon bolt,.a plurality of segments adapted to be expanded within a A substance, means for expanding said seg` ments at their inner ends, means forex- 40 panding said segments-at their outer ends, and means for retarding the expansion of said segments at theirouter ends to permit initial expansion at the inner ends thereof, substantially as described. l y

JOSEPH R. CONRAD.A

Witnesses: l

WALTER S. ROTH, EPHRAIM BANNING.

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