US3404503A

US3404503A - Anchor insert and releasable pick-up unit therefor

Info

Publication number: US3404503A
Application number: US569360A
Authority: US
Inventors: Peter D Courtois; George J Eriksson
Original assignee: Superior Concrete Accessories Inc
Current assignee: Superior Concrete Accessories Inc
Priority date: 1966-08-01
Filing date: 1966-08-01
Publication date: 1968-10-08
Anticipated expiration: 1985-10-08

Description

Oct. 8, 1968 p, cou o s ET AL 3,404,503

ANCHOR INSERT AND RELEASABLE PICK-UP UNIT THEREFOR Filed Aug. 1, 1966 3 Sheets-Sheet 1 FIG.

F/GZ

l Q so 60 H h l 54 84 7 INVENTORS.

PETER 0. COURTOIS 94 GEORGE J. IKSSON Oct. 8, 1968 P. D. COURTOIS ET AL ANCHOR INSERT AND RELEASABLE PICK-UP UNIT THEREFOR I Filed Aug. 1, 1966 3 Sheets-Sheet 2 INVENTORS. PETER D. COURTOIS GEORGE "J. ER SON .Oct. 8, 1968 P. o. couRTo1s ET AL ANCHOR INSERT AND RELEASABLE PIGK'UP UNIT THEREFOR s Sheets-Sheet 5 Filed Aug. 1, 1966 INVENTORS. PETER D. COURTOIS GEORGE J. ERIK SSON United States Patent r 3,404,503 ANCHOR INSERT AND RELEASABLE PICK-UP UNIT THEREFOR Peter D. Courtois, Des Plaines, and George J. Eriksson, Morton Grove, Ill., assignors to Superior Concrete Accessories, Inc., Franklin Park, 1",, a corporation of Delaware Filed Aug. 1, 1966, Ser. No. 569,360

6 Claims. (Cl. 52-701) ABSTRACT OF THE DISCLOSURE A two-part separable anchor insert and pick-up unit therefor designed for use in handling poured concrete slabs after the concrete thereof has hardened. The pickup unit embodies a pivoted bail which withstands appreciably greater pulling or lifting force than flexible cable lifting devices heretofore employed, and locking means are provided for preventing dislodgment of the pick-up unit from the anchor insert after a given lift of the slab has been initiated.

The improved anchor insert and pick-up unit comprising the present invention is designed for use primarily in connection with a concrete wall slab of the tilt-up variety,

the anchor insert being adapted to be embedded in one corner portion of the wall slab during formation of the latter and serving, in connection with similar anchor inserts in the other corner portions of the slab and after hardening of the poured concrete, as a medium whereby the slab may be detachably connected to a crane or similar hoisting mechanism to the end that the slab may be first raised while in a horizontal position and then tilted into a vertical position adjacent to the concretefloor slab in order to form a principal part of a building or other concrete structure. The pick-up unitis a counterpart of the anchor insert and consists of a tubular vertically elongated, bail-equipped casting within which there is vertically slidable a locking stem having a T-head at its lower end. The T-head is receivable in the anchor insert and, by imparting a twisting or turning motion to the stem, the -T-head may be caused to move into releasable interlocking relationship with respect to the insert. After such interlocking relationship has been attained, a nut, which is threadedly received on the upper end of the stem, may be tightened against the upper end of the casting in order to prevent release of the interlocked parts until such time as the nut is subsequently loosened.

The novelty of the present invention resides primarily in the specific form of the pick-up unit, the anchor insert of which it is a counterpart being substantially the same as the anchor insert which is shown, described and claimed in our copending United States patent application Ser. No. 500,491, filed on Oct. 19, 1965, now abandoned and entitled, Anchor Insert and Cable Pick-Up Unit Therefor. The present pick-up unit is considered to be an important or vital improvement over the cable pick-up unit of our aforesaid copending patent application in that it is of more rugged construction, is devoid of a twisted cable length which becomes frayed and weakened after repeated use, is possessed of appreciably greater tensile strength, is more appropriately shaped for storage in a small space, and is more readily releasably applied to its counterpart anchor insert. An advantage of the present pick-up unit resides in a certain locking feature whereby, after the unit has been effectively latched in position with respect to the anchor insert, such unit may then be locked in position against inadvertent unlatching.

The attainment of the above-enumerated and other advantages constitutes the principal object of the present 3,404,503 Patented. Oct. 8, 1968 See invention and other objects will readily suggest them selves as the nature of the invention is better understood from a consideration of the following detailed specification.

In the accompanying three sheets of drawings forming a part of this specification, one illustrative embodiment of the invention is shown.

In these drawings:

FIG. 1 is a top perspective View of an anchor insert embodying the principles of the present invention;

FIG. 2 is a bottom perspective View of the counterpart bail-equipped pick-up unit which is designed for cooperation with the anchor insert of FIG. 1;

FIG. 3 is a fragmentary side elevational view on an enlarged scale showing specifically the T -head construction that is employed in connection with the pick-up unit of FIG. 2;

FIG. 4 is a sectional view taken substantially centrally and vertically through the assembled anchor insert and pick-up unit, and showing the anchor insert operatively embedded and installed in a concrete wall slab;

FIG. 5 is a vertical sectional view taken on the line 5-5 of FIG. 4;

FIG. 6 is an exploded side elevational view, somewhat schematic in its representation, illustrating the anchor insert and the pick-up unit in the positions which they assume immediately prior to effecting the interlock operations between such parts;

FIG. 7 is a perspective view of the cable pick-up unit illustrating the manner in which it is manipulated when applied to its counterpart anchor insert; and

FIG. 8 is a top plan view of the anchor insert of FIG. 1.

Referring now to the drawings in detail and in particular to FIG. 1, the anchor insert 10 that is disclosed therein is substantially identical to the anchor insert of our copending patent application Ser. No. 500,491 above referred to. However, since this insert is a counterpart of the novel pick-up unit of the present invention and, in combination with such unit, involves a novel and useful combination, a full disclosure thereof is deemed necessary in the present application for United States Letters Patent. This anchor insert is designed for embedment in a tilt-up type concrete wall slab S and to form with similar inserts a medium whereby the slab may be detachably connected to a crane or other overhead hoisting mechanism to the end that the slab may be raised and subsequently tilted into a vertical position adjacent to a concrete floor slab in connection with the construction of a building or other concrete structure. Toward this end, the anchor insert 10 is designed for releasable cooperation with the novel pick-up device 12 that is illustrated in detail in FIGS. 2 to 7 of the drawings.

Still referring to FIG. 1, and additionally to FIG. 8, the anchor insert 10 involves in its general organization two crossed pairs of generally parallel rod lengths or sections 1 4 and 16, the latter being arranged in tic-tactoe fashion and welded together at their regions of crossing. The rod sections 14 are widely spaced and constitute a support for the anchor insert in its entirety so that the insert may rest or seat upon the foundation 18 of a slab form as shown in FIGS. 4 and 5. The rod sections 16 are more closely spaced and, together with the rod sections 14, constitute embedment rods which become widely distributed in the concrete slab S after a concrete pouring operation. The medial regions 20 of the rod sections 14 are linearly straight and extend horizontally while the end regions thereof are inclined downwardly as at 22 and then upwardly as at 24 to provide a pair of V-shaped foot portions which are covered at their apices with elastomeric sleeves 28. The latter are provided for the purpose of covering or shielding the metal foot portions which otherwise would become exposed at the bottom surface of the concrete wall slab S and would be likely to leave rust marks on such surface due to corrosion of these metal portions.

The rod sections 16 are provided with inverted wideangle' V-shaped medial regions 30 which merge with linearly 1 straight horizontal intermediate portions 32. These intermediate portions merge with outer, upwardly directed, reentrant hook-like portions 34. The apices of the inverted V-shaped medial regions 30 provide, in effect, downwardly facing thrust shoulders 36 which are designed for interlocking cooperation with counterpart shoulders on the associated pick-up unit 12 in a manner that will be set forth subsequently.

' Supported from the medial regions 30 of the rod sections 16 is a generally cylindrical, two-piece, sheet metal or plastic cage assembly 40, this assembly being comprised of telescopic sections including a lower cup-shaped section 42 and an upper ring section 44 of generally cylindrical configuration. The lower section 42 underlies the medial regions 30 of the rod section 16 while the upper ring section 44 overlies these medial regions. The upper rim region of the section 42 and the lower rim region of the section 44 are formed with

mating notches

46 and 48 which, when the lower rim region of the upper section is telescopically received within the upper rim region of the lower cup-shaped section 42, provide, in effect, a series of four spaced slots through which the medial regions of the rod section 16 pass when the cage assembly 40 is installed upon the welded wire assembly consisting of the

rod sections

14 and 16.

A pair of outwardly extending diametrically dispose wings 49 are formed on the upper ring section 44 of the cage assembly 40, these sections being conveniently formed by making the ring section in two 180 arcuate counter-part sections having laterally turned cars which, when brought into face-to-face contact and welded together, establish the two wings 49. The lower or bottom portions of these wings bear against the medial regions 20 of the rod sections 14 as shown in FIG. 1 and limit the extent of telescopic interfitting of the upper section 44 with respect to the lower section 42. Outwardly bowed circular ribs 56 serve to stiffen the upper ring section 44 in the medial region thereof and also serve to establish a bond 'for this section when it is embedded in the hardened concrete of the wall slab S.

The pick-up unit 12 of the present invention is comprised of a tubular body part 50 which is preferably in the form of a one-piece casting, is of generally cylindrical configuration, and includes an upper head portion 52, a lower pilot portion 54 of slightly reduced diameter, and an intermediate radial flange portion 56 of rectangular configuration. The wall of the upper head portion 52 is provided with diametrically disposed thickened regions 58 from which there project radially and outwardly two trunnions 60. A U-shaped bail 62 having parallel arms 64 and eyelets 66 at the lower ends of the arms is pivotally secured to the trunnions 60. The bight portion 68 of the bail is designed for cooperation with -a suitable lifting hook (not shown) which is associated with a crane or other hoisting mechanism by means of which the pick-up unit 12 may be hoisted after it has been operatively applied to and interlocked with the associated anchor unit in the hardened concrete slab S for slab-hoisting purposes as will be set forth in greater detail subsequently.

A vertically elongated torque stem 70 projects loosely and completely through the central bore 72 which is formed in the tubular body part 50 of the pick-up unit 12 and carries at its lower end a T-head 74. The upper portion of the stem 70 is formed with a comparatively coarse male screw thread 76 (commonly known as a contour thread) while the remaining portion of the stem is truly cylindrical. A knurled locking nut 78 is threadedly received on the upper portion of the stem and a horizontal rod 80 projects through, and fits with a drive fit in, a transverse hole or bore in the upper end of the stem and prevents removal of the nut 78. Said rod also forms a handle for stem-turning purposes. A washer 82 loosely surrounds the lower region of the stem 70 and a vertically extending coil spring 84 bears at its lower end against the washer 82 and at its upper end against a washer 86. The latter, in turn, bears upwardly against a pin 87 (see FIG. 3) which extends diametrically through the central or intermediate portion of the stem 70.

The effective length of the stem 70 is appreciably greater than the over-all vertical extent of the tubular body part 50 so that when the nut 78 is disposed on the upper region of the stem and the body part is freely suspended by way of the bail 62, the two

washers

82 and 86 and the spring 84 between them are fully exposed as shown in FIG. 3. However, when the stem 70 is raised relatively to the body part 50 as shown in the unnatural position of the parts shown in FIG. 2, the upper washer 86 and a portion of the spring 84 are drawn into a socket 88 that is formed in the lower pilot portion 54 of said body part.

In the operation of the herein-described anchor insert 10 and pick-up unit 12, in order to form a slab such as the slab S, the slab form is erected in the usual manner and at each location within the form where an anchor point is to be effected in the finished slab, one of the assembled anchor inserts 10 is positioned on the form foundation 18 with the four elastomeric sleeves 28 resting upon the upper surface of such foundation. A suitable hollow post or sleeve (not shown) is positioned in the upper rim region of the ring section 44 of the cage assembly 40 of each insert so that it projects vertically or upwardly to the level of the upper surface of the slab to be formed and excludes the entrance of concrete into the interior of the cage assembly 40. The cage assembly may be further sealed by forcing a suitable putty-like substance 90 into the

notches

46 and 48 and packing the same tightly about the ends of the medial regions 30 of the rod sections 16. The concrete is then poured into the form to the desired height or thickness and allowed to harden. Thereafter, the aforementioned posts or sleeves are removed from the upper rim regions of the ring section 44 of the various insert, thus leaving cylindrical passages or holes 92 in the concrete and in vertical register with each cage assembly 40. The anchor inserts 10 are then ready for interlocking cooperation with a corresponding number of pick-up units 12 for hoisting purposes.

In order to establish such interlocking cooperation between an anchor unit 10 and a pick-up unit 12, the opera.- tor utilizing the bail 62 as a handle will align the pilot portion 54 of the tubular body part 50 with the selected hole 92 in the concrete with the T-head 74 oriented as shown in FIG. 6 so that it will pass freely between the two inverted V-shaped medial regions 30 of the rod sections 16 and extend into the lower cup-shaped section 42 of the cage assembly 40 well below the level of such medial regions 30. Thereafter, the entire pick-up unit 12 may be bodily lowered to project the pilot portion 54 into the hole 92 and cause the rectangular flange portion 56 to seat upon the upper surface of the concrete slab S as shown in FIG. 7. At the same time, the lower end of the pilot portion 54 will seat upon the upper rim of the upper ring section 44. The nut 78 at this time will assume a position adjacent to the top or upper portion of the stem 70. The diameter of the washer 82 is appreciably greater than the distance between the two rod sections 16 so that this washer will come to rest upon the apices of the V- shaped medial regions 30 of said rod sections and the stem 70 will be yieldingly supported from the washer 82 through the medium of the spring 84 and the cross pin 87 to the end that the T-head 74 will come to rest substantially at the level of the V-shaped medial regions 30 of the two rod sections 16. Thereafter, as shown in FIG.

7, the Operator will apply downward pressure to the stem 70 to force the same downwardly against the yielding action of the spring and cause the T-head 74 to become lowered below the level of the V-shaped medial regions 30 of the rod sections 16, thereby compressing the spring 84. As soon as the T-head has thus cleared these medial regions 30, the operator will then turn or twist the stem 70 in either direction so as to bring the axis of the T- head into transverse relationship with respect to the vertical planes of the rod sections 16, at which time the T-head 74 will then underlie said medial regions 30. Upon release of the stem 70, the spring 84 will serve to raise the stem to the position wherein it is illustrated in FIGS. 4 and 5 with the upper faces of the T-head on each side of the stem 70 bearing upwardly against the medial re gions 30 of the rods 16. In order to maintain such interlocking relationship between the T-head 74 and the rod sections 16, a pair of recesses 94 are formed in the upper side of the T-head, the extreme apices of the V-shaped medial portions 30 of the rods 16 seating within these recesses after manual pressure on the stem 70 has been discontinued. These recesses 94 establish lift shoulders which are designed for engagement with the downwardly facing thrust shoulders that are established by the apices of the V-shaped medial regions 30 of the rod sections 16.

As soon as the interlocking relationship between the T-head and the rod sections 16 of the cage assembly 40 has been attained, the operator will then screw the nut 78 downwardly on the stem 70 in order to draw the latter upwardly under tension and positively lock the T-head in position against dislodgrnent. The nut 78, in addition to serving as a locking element, further serves as a reaction member to assimilate the upward thrust of the body part 50 when the latter is lifted upwardly by the bail 62 under the influence of the aforementioned crane or overhead hoisting mechanism. At such time as the crane hook has been attached to the bail 62 and hoisting operations have commenced, the stem 70 and the nut 78 will assimilate the entire downward pulling force of the anchor insert and the mass of hardened concrete which is served by the particular embedded insert under consideration. This downward pulling force is exerted on the nut 78 through the tension in the torque stem 76.

At such time as the slab has been hoisted to its final position as, for example, to a vertical position when h slab is to be used in the formation of a vertical wall, release of the interlocking connection between the pick-up unit 12 and the anchor insert 10 may be effected by backing off of the nut 78 to such an extent that downward pressure upon the latch stem 70 will permit lowering of the same so as to force the T-head out of engagement with the two rod sections 16. After such depression of the stem 70, torque or turning movement may be applied to the stem through the medium of the handle-forming rod 80 so as to bring the T-head to a position of angular register with the space existing between the two rod sections 16 whereupon the entire lower region of the pickup unit may be withdrawn axially from the anchor insert and the hole 92.

Such removal of the pick-up unit 12 from the anchor unit 10 exposes the hole 92 for filling with a suitable patching cement. Such cement, when applied to the hole and smoothed to the general plane of the upper surface of the slab S which now extends in a vertical plane, serves completely to conceal the anchor insert and restore the upper surface of the slab to a smooth unbroken configuration. The removed pick-up unit is then available for reuse in a subsequent installation and pick-up operation.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings 01' described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. Therefore, only insofar as the invention is particularly pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

1. In combination, an anchor insert adapted for embedment in a concrete slab and a cooperating pick-up unit therefor, said anchor insert comprising a concrete-excluding cage across which there extends internally thereof a pair of parallel parts defining downwardly facing spaced apart thrust shoulders, said cage having an open upper rim, said pick-up unit comprising a generally cylindrical body part adapted to be positioned on the upper surface of the slab and having therethrough a central vertical bore designed for register with said open upper rim when the body part is in position on the slab, a vertical torque stem projecting completely and loosely through said bore and provided with a T-head at its lower end, said T-head defining a pair of upwardly facing lift shoulders on opposite sides of the stem and designed for interlocking engagement with said downwardly facing thrust shoulders when the stem is projected through said open rim to an extent sufficient to project the T-head below the level of and between said parallel parts and then turned through an angle of approximately the upper region of said stem being threaded, a locking nut threadedly received on said upper region of the stem and designed for engagement with the upper rim of said bore to draw said stem upwardly and thus pull the lift shoulders hard against said thrust shoulders, attachment means on said body part whereby the pick-up unit may be attached to an overhead hoist, said attachment means comprising a pair of trunnions projecting outwardly on opposite sides of said body part, and a U-shaped bail having arms provided at the outer ends thereof with eyelets through which the trunnions extend.

2. The combination set forth in claim 1 and including, additionally, spring means effective when said T-head is disposed below the level of the parallel parts for yieldingly urging the T head upwardly into engagement with said parallel parts.

3. The combination set forth in claim 1 and including, additionally, a handle-forming rod projecting through said torque stem transversely thereof adjacent to the upper end of the latter.

4. The combination set forth in claim 2 and wherein the spring means comprises a washer loosely surrounding said torque stem immediately above said T-head, means defining a downwardly facing shoulder on the torque stern, and a coil spring surrounding the torque stem and effectively interposed between said washer and said downwardly facing shoulder, the diameter of the washer being greater than the distance between said rod portions whereby the Washer will seat upon said parallel parts when the torque stem is initially introduced into the cage through the open upper rim thereof.

5. The combination set forth in claim 2 and wherein the downwardly facing shoulder on the torque stem is established by a cross pin which projects diametrically through the stem.

6. In combination, an anchor insert adapted for embedment in a concrete slab and a cooperating pick-up unit therefor, said anchor insert comprising a concreteexcluding cage across which there extends internally thereof a pair of parallel parts defining downwardly facing spaced apart thrust shoulders, said cage having an open upper rim, said pick-up unit comprising a generally cylindrical body part adapted to be positioned on the upper surface of the slab and having therethrough a central vertical bore designed for register with said open upper rim when the body part is in position on the slab, said body part comprising an upper head portion, an intermediate radial flange portion and a lower pilot portion, said flange portion being designed for seating engagement with the upper surface of the slab within which the anchor insert is embedded, said pilot portion being adapted for projection through a preformed hole in the slab in register with said open upper rim of the cage, a vertical torque stem projecting completely and loosely through said bore 7 and provided with a T-head at its lower end, said T-head defining a pair .of. upwardly facing lift shoulders on opposite sides of the stern and designed for interlocking engagement with said downwardly facing thrust shoulders when the stem is projected through said openrim to an extent sufiicient to project the T-head below the level of and between said parallel parts and then turned through an angle of approximately 90, the upper region of said stern being threaded, a locking nut threadedly received on said upper region of the stern and designed for engagement with the upper rim of said bore to draw said stem upwardly and thus pull the lift shoulder hard against said thrust shoulders, and attachment means on said body part whereby the pick-up unit may be attached to an over- 8 trunnions projecting outwardly on opposite sides of said body part, and a U-shaped bail having arms provided at the outer ends thereof with eyelets through which the trunnions extend.

References Cited UNITED STATES PATENTS 1,037,142 8/1912 Hazen 52701 2,719,747 10/1955 Layne 29489 3,124,385 3/1964 Neptune 52 711 XR 3,297,293 1/1967 Andrews et a1. 248361 BOBBY R. GAY, Primary Examiner.

head hoist, said attachment means comprising a pair of 15 CALVERT, A-Ysislalll Examine!-