US1298105A

US1298105A - Tie-rod-withdrawing jack.

Info

Publication number: US1298105A
Application number: US26529218A
Authority: US
Inventors: Robert Sharp
Original assignee: Individual
Current assignee: Individual
Priority date: 1918-12-04
Filing date: 1918-12-04
Publication date: 1919-03-25
Anticipated expiration: 1936-03-25

Description

y R. SHARP.

TIE ROD WITHDRAWING JACK. APPLICATION FILED DEC. 4, l9l8.

W/T/VESSES Patented Mar. 25,1919.

PATENT onirica.

ROBERT SHARP, OF TUCKAHOE, NEW YORK.

TIE-ROD-WITHDRAWING- JACK.

Application filed December 4., 1918.

To all whom t may concern:

Be it known that I, ROBERT SHARP, a citiprovement in the method of forming con-v crete constructions in those situations where the mold boards of the form are tied together by metal rods embedded in the concrete and which usually remain in position at least until the concrete -hasset The primary object of the invention is to provide a concrete mold construction, and particularly a tie rod therefor, all the parts of which mold construction maybe used repeatedly without the necessity of reforming the parts7 and incidental to this primary object it is desirable to provide in such a construction, a tie rod for the concrete which will permit the form boards to be removed earlier than these boards can be removed Linder present practices.

Broadly the invention contemplates a form of tie rod which will not only act to tie the boards together durino` the pouring and initial stages of the setting operation but which will also tie together the outer portions where the setting process has farthest advanced. With this form of concrete tying rod it is possible, as soon as these outer shells of concrete have a rigidity suiiicient to hold the configuration of the structure to remove the boards so that they may be used iii-another location.

It has been suggested that tie rods for the molds be made smooth and when the concrete has set sufficiently to permit the removal of the form to withdraw the rods by means of a turn-buckle arrangement one threaded portion of which bears on the outer wall of the mold and another similar portion engages a crimped portion of the smooth rod.

In the improved method, herein disclosed, however, it is necessary to allow the rods to remain in the concrete after the premature removal of the boards and especially where the rods are allowed to remain for any material time the concrete adheres to the rod tov such an extent that the adoption of the Specification of Letters Patent.

Patented Mar. 25, 1919.

Serial No. 265,292.

suggested use of a turn-buckle to pull the rods loose is impossible and impractical.

Accordingly, the invention features a powerful rod withdrawing device capable of loosening the adhesion between the rod and concrete and designed to Withdraw the rod rapidly and without bending after it has been loosened from its original position in the concrete.

With the concrete exposed any attempt to pull the tie rod longitudinally out of position would result in the rod bringing with it some of the concrete. This is avoided by first giving the rod a slightly rotary movement about its own axis soa that the initial withdrawing movement is somewhat in the nature of a -screw action. When loosened the rod may be withdrawn longitudinally without any material damage to the concrete.

In Such operations there is grave danger of bending the rods and especially where the rods are screw-threaded, any such bending would minimize the possibility of immediately reusing the rods in another part of the structure.

Accordingly, another object of the invention is to provide a guiding means for engaging as much of the tie rod as possible, taking into consideration the commercial necessity of making the device of the least practical length so as to apportion the portable weight of material into a minimum number of massive parts rather than feature a long screwing device.

Various other objects and advantages of the invention will be in part obvious from an inspection of the accompanying drawings and in part will be more fully set forth in the following particular description of one form of mechanism embodying my invention, and the invention also consists in certain new and novel features of construction and combination of parts hereinafter set forth and claimed.

In the accompanying drawings Figure l Vis a view in vertical section transversely of a concrete wall with the form boards in position, tied together by means of a tie rod constituting a part of a preferred form of my invention;

Fig. Q is a perspective view of the wall shown in Fig. l with the mold boards removed and showing the parts of a preferred form of my invention in operative engagement with one of the rods to withdraw the same; and

F ig. 3 is a view in side elevation of the jack constituting a part of the withdrawing means shown in Fig. 2.

In the following description and in the claims, -parts will be identified by specific names for convenience of expression lbut they are intended to be as lgeneric in their application to similar parts as the art will permit.

There is shown a wall A ot concrete or similar self-hardening plastic material which has been poured into the form and between the boards B thereof. During the` pouring operation and during the initial periods of the setting operation the boa-rds l are held in position by means ot tie rods l() which extend beyond opposite faces of the boards B and the boards are held in position by means ot' nuts C in threaded engagement with the rods 10. For this purpose the end portions of the rods are providedwith screw threads 1l and in one phase of the invention the threads are arranged so as to extend into the outer portions of t-he concrete as shown in Figs. 1 and 2. These threads are'arran'ged to form corresponding threads 1Q, in the outer yportions of the concrete as it becomes set. As is known the concrete sets progressively Yfrom the outer exposed sides inwardly toward vthe interior of the concrete structure and by connecting these "set portions it possible to utilize the mold-board-tie-rods for the purpose ot' tying `together the outer portions of the wall A. There is therefore formed, in effect, a pair of spaced apart and tied together shells whichwill maintain the configuration of the wall until the concrete has entirelyl set. By this means it is possible to remove the mold boards shortly after the wall is poured. This exposes the outer sidesI of the wall earlier than usual and tends to facilitate the rapid setting of the concrete. The lrods therefore remain in the concrete longer than has been usual in prior situations where it is suggested t0 withdrav,v the rods prior to or at the same time that the mold boards areremoved.

The mechanism for withdrawing' the rods features a massive construction made sulliciently light'in weight so as to be handled by one man but with the metal so proportioned as to give the'maximum resist-ance to bending 'or distortion when in use. Feat-uring the simplicityof construction there ris shown a=screw jack 14;7 formed primarily ottwo screw parts. One ofthe partsis a hollow casting flha'vi-ng one end enlarged to form a flange 16 for engaging theconcrete overamateiial area thereof andwhich a is held against rotary movement by the frictional engagement with the concrete engaging surface 17 forming the adjacent side of the concrete construction. This bearing element forms the female member of the screw combination and Vhas a bore 18 of relatively large diameter ovided with internal screw threads prefera ly of the square threaded type which have been found most effective to give the requisite strength to the threaded part of `this rodv withdrawing jack. The other member of the screw connection is relatively long and isl provided with abore 19 4extending "axially therethrough. This bore has a diameter suiicient to acconimodate the rod 10 passed therethrough as shown in Fig. 2. In its most perfected construction the rod should have a sliding tit in the bore so that the rod would beguided tor the entire length of this member, but as these rods are usually made up ot rough stock'there should be sufficient clearance between the rod and'shiftablemember to permit a free movement of the rod but this clearance should'be no niore than necessary so that the membermay actas a guide Jfor engagingttl'ie greatest possible length of rod, and thus tend to prevent distortion of the rod in' the wit-l'idrawal of the same fromthe lconcrete. Y

This member 1s provided centrally thereof witha massivey head 20 having openings Q1 extending laterallytherethrough to accommodate a long crow-bari@ or similar leverage tool necessary when suchdevices are-ac tuated by manual force.

AWhere it is desired to rotate the rod 10 .slightly in the initial loosening of thesame from lthe concrete, the rod 10' is provided with al1-opening extending therethrough and `which opening is designed to be alined with one ot the openings 21 in the head thus permitting the insert-ion of the crow- Y end ot the member opposite the shank is reduced to forma relatively small bearing tube 25 upon which vis loosely mounted a washer 26, one side of which is in bearing engagement with the head and the opposite side of which constitutes a nut engaging surtace 27. A nut- 28 is threaded on therod l() and inthe actuation ofthe device'whenit is desired tomove the rod@longitudinallythis nut screwed up intofengagement witltthe washer.

In operation yand with' the mold boards removed, or even with Vthe mold boards in position, the jackie slippedon the projecting end of the rod and with the shank telescoped fully into the female member. The

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nut 28 is then screwed onto the rod until it is in bearing engagement with the washer 26. 'Ihen by inserting the crow-bar into the opening 2l but not into the opening the male member may be rotated in a direction to withdraw the same out of the female member and to yact through the washer and nut to withdraw the rod longitudinally out of the set concrete. v

In those situations where it is desired to rst loosen the rod by a rotary movement thereof, the nut 28 is omitted and the crowbar passed entirely through the rod, so that with the rotation of the male member the rod will be unscrewed from the threaded concrete part and when the rod is thus ini tially loosened the nut 28 may be screwed up into position as previously' suggested and the rod rapidly withdrawn by the rotation of the male member. It is preferable from a mechanical standpoint to make the shank relatively short and as it approaches the outward limit of its movement to rotate the same back into its collapsed position, then rotate the nut into the advanced position to again engage the washer and the operation is continued, and if necessary repeated until the rod is fully withdrawn from the Set concrete.

By means of a device of this character it is possible to remove the mold boards, so that on a given undertaking the amount of lumber utilized is reduced and withdrawing the rods without bending maintains the threads thereon intact and permits the repeated use of the rod, Without the necessity of straightening the same. The jack can be quickly installed in position and as there are but two screw parts, and these parts are necessarily made quite rugged the possibility of distorting the parts through the excessive force necessary in such a situation is reduced to a minimum.

It is obvious that the jack illustrated may be utilized in other locations, for instance, where it is desired to draw on a rod or cable. As one illustration of such a use, it niay be noted that the ack could be mounted on a tripod and a lifting rod disposed vertically in place of the rod l0 or the jack could be mounted on a suspension bridge tower to draw the cables taut.

Having thus described my invention. I claim:

l. In a device of the class described, the combination with' a tie rod for connecting the mold boards of a concrete form, one end of said rod which is designed to extend beyond the concrete being threaded and provided with a hole extending transversely therethrough, of a `iack provided with an opening extending axially therethrough for receiving the threaded portion of the rod, said jack including a female bearing member internally screw threaded and provided with a concrete engaging end, a male member provided with a massive head and a shank portion in threaded engagement with the bearing member, said head provided with an opening extending therethrough and designed to be alined with the opening in the rod whereby a crow-bar or similar leverage tool may be inserted in said alined openings and the head and rod rotated simultaneously thereby to screw the rod out of the concrete.

Q. In a device of the class described, the combination with a tie rod for connecting the mold 'boards of a concrete form, and provided with a hole extending transversely therethrough, of a jack provided with an opening extending axially therethrough for vreceiving a projecting port-ion of the rod, said ack including a female bearing member internally screw threaded and provided with a concrete engaging end, a male member provided with a massive head and a shank portion in threaded engagement with the bearing member, said head provided with an opening extending therethrough and designed to be alined with the opening in the rod whereby a crow-bar or similar leverage tool may be inserted in said alined openings and the head and rod rotated simultaneously thereby to loosen the adhesion between the rod and the concrete.

3. In a device of the class described. the combination with a tie rod for connecting the mold boards of a concrete form, one end of said rod, which is designed to extend beyond the concrete, being threaded, of a screw jack provided with a hole extending axially therethrough for receiving the threaded portion of the rod, said jack including a female bearing member internally screw threaded and provided with a concrete engaging end, a male member provided with a head adapted to be engaged by a rotating tool and provided with a shank in threaded engagement in said female member and a nut in threaded engagement with said rod to the outside of said male member whereby the rotation of said head in one direction will move the same into bearing engagement with the nut and act thereon to draw the rod axially out of the lconcrete and without bending the rod, said nut adapted to be advanced on the rod.

4. In a device of the class described, the combination with a tie rod for connecting the mold boards of a concrete form`r` one end of said rod, which is designed to extend beyond the concrete, being threaded, of a screw jack provided with a hole extending axially therethrough for receiving the threaded portion of the rod,'said jack including a female bearing member internally screw threaded and provided with a head adapted to be engaged by a rotating tool and provided with a shank in threaded engagement in said female member, a nut in threaded engagement with said rod to the outside of said male member whereby the rotation of said head in one direction will move the same into bearing engagement with the nut and act thereon to draw the rod axially out of the concrete and without bending the rod, said nut adapted to be advanced on the rod, and a washer loosely mounted on the male member and disposed between the revoluble head and the nut threaded on the rod.

5. In a device for withdrawing a tie rod from a concrete construction, a screw jack Aformed of two parts, one of said parts constituting a female short bearing member with one end enlarged to form a concrete engaging end designed to extend over an extensive area of the concrete and the other part constituting a male member provided with a head and a shank portion threaded finto said female member, said male member provided with an opening extending axially therethrough and having a diameter designed to accommodate the rod acted upon and approximately to engage said rod to minimize any tendency of the rod to bend,

said head provided with means for receiv-` ing a leverage tool to rotate the male mem- 'ber out of the female member.

6. A screw jack for withdrawing tie rods from concrete constructions, including a female Ibearing member with one end forming a concrete engaging end and having a bore of relatively large diameter extending axially therethrough, a shiftable rod guiding member provided with a bore extending axially therethrough for accommodating the tie rod for a distance substantially equal to the length of the jack when collapsed, said guiding member provided centrally thereof with a head adapted to be engaged by a leverage tool to rotate the guiding member, a shank of relatively large diameter constituting a male member and fitted `in said large diametered bore and in screw threaded engagement with said female member, a

bearing tube of relatively small external diameter extending from the side of the hea-d opposite the shank and a washer loosely mounted on said tube whereby the rod guid ing member may be rotated about the rod being withdrawn, relative to both the washer and the female member while being withdrawn from the female member.

7. A screw jack for withdrawing tie rods from concrete constructions including a female bearing member with one end enlarged to form a concrete engaging end and having a relatively large bore extending axially therethrough and internally screw threaded, a male member having a head adapted to be engaged by a tool to rotate the member and having a shank fitted in said large bore, externally screw threaded and engaging the threads of the female member, said head and shank having a smooth bore extending axially therethrough and adapted substantially to engage the rod along the entire length of the male member thereby to assist in minimizing any tendency of the rod to become bent during the withdrawal thereof` from the concrete.

8. A screw jack for withdrawing tie rods from concrete construction, comprising two threaded parts, one part constituting a female member adapted to be held in yfixe/d position relative to the concrete structure and the other part constituting a coacting male member threaded into said female member, said `male member provided with a rod receiving bore extending axially therethrough and a washer mounted loosely on said head at the end thereof oppositethe end in threaded engagement in the female member, the outer end of said washer provided with a nut-engaging surface.

Q. In a device of the class described, the combination of a screw jack comprising two threaded parts, one part constituting a female member adapted to `be held in fixed position relative to the concrete construction and the other part constituting a coacting male member threaded into said female member, said male member provided with a rod receiving bore extending axially therethrough and washer mounted loosely on said head at the end thereof opposite the end in threaded engagement in the female member, the outer end of said washer provided with a nut engaging surface and a nut adapted to be threaded on the rod and engaged by said nut engaging surface to withdraw the rod from the concrete when the male member is rotated in one direction.

Signed aft New York city, in the county of New York and State of New York this '27th day of November A. D. 1918.

ROBERT SHARP.V

k(Jolcl o! this patent mary be obtained for ve cents each, by addressing the Commissioner of Intenta.

-Wnshington, D. c.