US3025742A - Anchor bolt comprising separate shells having inclined ramp surfaces to be expanded by a wedge-shaped block drawn therebetween - Google Patents

Description

. J. LEMOINE 3,025,742 ANCHOR BOLT COMPRISING SEPARATE SHELLS HAVING INCLINED RAMP SURFACES TO BE EXPANDED BY A WEDGE-SHAPED BLOCK DRAWN THEREBETWEEN Filed April 2, 195a 2 Sheets-Sheet 1 March 20,1962 M.C

W AI E LEMOINE 3,025,742

' March 20, 1962 M. c. J.

ANCHOR BOLT COMPRISING SEPARATE SHELLS HAVING INCLINED RAMP SURFACES TO BE EXPANDED BY A WEDGE-SHAPED BLOCK DRAWN THEREBETWEEN 2 Sheets-$heef 2 Filed April 2, 1958 IIIIIIII I .V

W with;

Unite 3,625,742 Patented Mar. 26, 162

3,025,742 ANCHOR BOLT COMPRESING SEPARATE SHELLS HAVING INCLINED RAMP SURFACES TO BE EXPANDED BY A WEDGE-SHAPED BLOCK DRAWN THEREBETWEEN Marcel Camille .lean Lemoine, Saverne, France, assignor to Anciens Etablissements Goldenberg & Cie, Saverne, France, a corporation of France Filed Apr. 2, 1958, Ser. No. 725,838 Claims priority, application France Apr. 19, 1957 6 Claims. (Cl. 85-14) The present invention relates toanchoring devices, and in particular anchoring devices of the type comprising a traction rod provided with one or more groups of cams co-operating with corresponding groups of ramps provided on shells applied around the rod.

These anchoring devices are used for many purposes and in particular for setting objects in walls, bedding down machines, and for any application in which an object is held fast in material in which it is possible to make a hole. These devices are mostly used in mines for bolting roofing, facings and the wall.

One of the disadvantages of known anchoring devices is that the cams are not positively guided in the course of their displacement relative to the shells. There is consequently danger of offset occurring between the shells and the cams impairing the effectiveness of the anchorage obtained.

The object of the invention is to provide an anchoring device of the aforementioned type which remedies this disadvantage and provides further advantages.

The anchoring device of the invention is characterised in that one of the groups of cams is constituted by an apertured block in the aperture of which are inserted guide means protruding from the inner face of the shells.

These guide means ensure that the cams carried by the traction rod remain facing their corresponding ramps formed on the shells during the whole of the expansion of the shells.

Further, these guide means could be utilized as a support for connecting means which interconnects the shells and extends through said aperture. The aperture in the block is defined at its upper part by a wall which in contacting the guide means or the connecting means prevents separation of the shells and of the block.

In a preferred embodiment, the connecting means is constituted by a rigid pin, such as a rivet, slidably mounted in the guide means and permitting the transverse separation of the shells while preventing relative longitudinal movement between said shells.

Further features and advantages of the invention will be apparent from the ensuing description, with reference to the accompanying drawings, to which the invention is in no way restricted.

in the drawings:

FIG. 1 is a perspective view with a part cut away of one embodiment of the invention;

FIG. 2 is a longitudinal sectional view with a part cut away of a second embodiment of the invention;

FIG. 3 is a sectional view taken along line 33 of FIG. 6;

FIG. 4 is a longitudinal sectional view taken along line 44 of FIG. 6 of the first embodiment of the invention;

FIG. is a partial longitudinal sectional view of a detail of the embodiment shown in H6. 1, and

FIGS. 6, 7 and 8 are longitudinal sectional views of three stages of expansion of the anchoring device shown in FIG. 1.

In the embodiment shown in FIG. 1, the anchoring device comprises two shells 1 and 2 which constitute by their adjacent relationship a segmented tube. These shells comprise notches or recesses 3 on their outer face, adapted to facilitate the anchoring of the shells in the wall of the bored hole and are provided at their lower part with longitudinally-extending slots 4 the purpose of which will be described hereinafter.

The segmented tube formed by the shells 1 and 2 encompasses a traction rod 5 carrying a group of cams A.

In accordance with the invention, this group of cams is formed by a block in the form of a wedge defined by two lateral opposed faces 6 interconnected at their upper part by a bridge 7. The space 8 between the two faces 6 is apertured forming two thin walls or strips 9 corresponding to the faces 6 of the block A. Thus these strips 9 constitute the cam faces of the block A and cooperate with similarly inclined ramps 19 formed at the joints of the shells 1 and 2.

The inner face of each of the shells comprises a projection or boss 11 (FIGS. 1 and 3) adapted to extend into the aperture 8 and'thus constitute guide means for the shells. The bosses 11 are provided with apertures 12 in which is slidably mounted a pin or rivet 13 which is burred or riveted over at each end 14. This pin interconnects the shells 1 and 2 through the aperture 3 and thus permits the shells to separate transversely of the anchoring device While preventing relative longitudinal movement between the shells. To ensure that the shells and the cams are held together before use, elastically yieldable connecting means 15, bearing in one of the notches 3 or in a recess provided for this purpose in the outer face of the shells, apply the shells against the cams A.

The rod 5 is connected to the cam block A by a second block or wedge 16 (FIG. 4). This block is provided with a tapped hole 17 at its upper part and receives the screw-threaded end 18 of the rod 5. A stud 19 is screwthreadedly engaged in the end 18 of the rod 5 and comprises at its upper end an abutment head 29.

The hollow block 16 is in the form of a truncated pyramid Whose lateral faces 21 constitute the second group of cams co-operating with similarly inclined ramps 22 provided in the inner face of the shells on either side of the longitudinal slot 4.

The lower end of the rod 5 carries a nut 23 which is engaged on the lower screw-threaded end portion 24 of the rod and retains a support plate 26. Th nut 23 is arranged in a special manner as shown in FIG. 5. It is not completely tapped, its lower part 27 being unfinished in that its diameter corresponds to the diameter of the hole drilled prior to tapping the nut.

It will be understood that owing to this arrangement, when the nut 23 is moved to the end of the screw-threaded portion 24 on the rod 5, it is rendered rigid with the latter as concerns rotation so long as a given driving rotational force, corresponding to the resistance of the material of the nut to the tapping force exerted thereon by the screw-threaded portion 24, is not exerted on the nut. As soon as this force is exceeded, the bottom 27 of the nut is tapped by the screw-threaded portion 24 and the nut is capable of being screwed along the portion 24 with which it is no longer rigid.

In the embodiment shown in FIG. 1 there are provided two groups of cams constituted respectively by the faces 9 of the block A and the faces 21 of the block 16. The faces of the cam 9 effect a diametral expansion of the upper part of the shells and the faces 21 effect a circumferential expansion of the lower part of the shells, permitted by the slots 4. The operation and the advantages of these two groups of cams arranged in this manner are described in detail in applicants co-pending patent application Serial No. 725,845 filed on the same day as the present application and entitled Anchoring Device.

' As concerns the present invention, it is by no means indispensable that the cams should be arranged in the manner shown in FIG. 1. The essential thing is that the traction rod carry at least one group of cams constituted by an apertured :block in the aperture of which extend the guide means protruding from the inner faces of the shells.

Thus in FIG. 2 there has been shown an embodiment of the anchoring device which is identical to that shown in FIG. 1 except that the block 16a is cylindrical and has no cam face, the only cams being those of the block A which are longer than those shown in FIG. 1. Consequently, the lower parts of the shells have no longitudinal slots 4.

Numerous other embodiments of the invention are possible in which a group of cams, such as the group A, is associated with one or more other groups of cams which have a diametral or circumferential action. The group of cams A could then constitute the upper or lower group of cams of the rod or an intermediate group located between two other groups.

The operation of the anchoring device of the invention will now be described, with reference to FIGS. 6-8.

In FIG. 6 the anchoring device has just been inserted in the bored hole T. Owing to the force of gravity or a manual traction, the rod and its groups of cams have descended slightly and slightly opened the shells 1 and 2. This ensures that the shells anchor or hook in the wall of the bored hole which hooking is favored by the recesses 3.

As can be seen in FIG. 6, the rod 5 has not been screwed sufficiently into the block 16 to permit the head 20 of the stud 19 to abut the guide means 11.

The second stage of anchoring consists in driving the rod 5 in rotation by means of the nut 23 which is wedged against the end of the screw-threaded portion 24 of the rod. In the course of this rotation, the rod 5 screws into the block 16 and the cam remains stationary until the head 20 abuts the lateral face of the guide means 11 (FIG. 7). Thenceforth, further rotation of the rod, which cannot move longitudinally, causes a downward movement of the block 16 and of the cam block A rigid therewith.

In the course of their downward movement, these cams separate the shells, the expansion of the upper part being diametral and that of the lower part circumferential, as mentioned hereinbefore.

In the course of this separation of the shells, the bosses 11 guide the downward movement of the group of cams A and thus prevent any relative rotation between, on one hand, the unit comprising the rod 5 and the cams 9 and 21 carried thereby and the shells on the other. Thus, there is ensured a perfect co-operation between the cams and the ramps during the whole of the expansion. The bosses 11 slide transversely along the pin 13 so that the latter does not hinder the expansion. On the other hand, the pin prevents any longitudinal relative movement between the shells. The rotation of the rod 5 encounters an increasing resistance due to the resistance of the surrounding material or earth with increased separation of the shells. This resistance subsequently exceeds that which opposes the tapping of the end 27 of the nut 23 by the screw-threaded portion 24 of the rod 5. At this moment, the end 27 of the nut is tapped and the nut 23 is screwed along the rod and the latter ceases to rotate. T henceforth, anchoring can proceed, if necessary, by continuing to screw the nut 23 along the rod 5.

In the first stage, the screwing of this nut merely takes up the play, if any, between the plate 26 and the outer end of the bored hole. Once this play has been taken up, further screwing of the nut along the rod exerts traction on the latter which moves downwardly causing downward movement of the two groups of cams (FIG. 8).

It is clearly seen in FIG. 8, which represents the last stage of anchoring, that the head 20 has left the lower face of the guide means 11 and that the nut 23 has been screwed along the screw-threaded portion 24 of the rod i 5. The expansion of the anchoring device is terminated when the bridge 7 of the block A abuts the upper face of the guide means 11, as shown in FIG. 8.

The advantages of the guide means 11 will be obvious from the foregoing. These guide means ensure a correct positioning of the cams and ramps during the whole of the expansion. They permit moreover a positive connection between the shells by means of the pin 13. Further, the abutment of the head 26 against the guide means determines the expansion of the anchoring device, this expansion being limited by the abutment of the bridge 7 against the same guide means.

Although specific embodiments of the invention have been described, many modifications and changes may be made therein without departing from the scope of the invention as defined in the appended claims.

Thus, as mentioned hereinbefore, it is possible to associate the apertured block A with one or more other groups of cams or it can be the only group of cams. Further, the nut 23 could be held rigid with the rod 5 as concerns rotation up to a predetermined rotational force by means other than that shown in FIG. 5. Thus, this nut 23 could be provided with a pin which extends therethrough and through the rod 5 and shears upon application of a pre-determined rotational force. It is also possible to construct the nut 23 so that it has a blind. tapped hole the base of this nut shearing upon application of a predetermined rotational force.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

l. Anchoring device comprising separate shells assembled so as to form a segmented tube and provided with at least one group of inclined surfaces forming ramps, a rod longitudinally disposed in said tube, at least one group of inclined surfaces providing cams formed on a wedge-shaped block which has a transverse aperture, said block being carried by one end of said rod, and longitudinally movable therewith relative to said shells when a traction is exerted on said rod, said group of cams being adapted, when moving relative to said shells, to co operate with said group of ramps so as to effect an expansion of said shells, the latter further comprising guide and connecting means constituted by hollow projections having a transverse base extending from the inner face of said shells radially relative to said tube and protruding into said aperture and an element extending through said transverse bases and having headed ends normally spaced from said bases and positioned in said hollow projections without projecting externally of the shells and extending through said aperture, the other end of said rod comprising means for exerting a traction on said rod, whereby the latter and said wedge are moved longitudinally relative to said tube to expand it.

2. Anchoring device comprising separate shells assembled so as to form a segmented tube and provided with at least one group of inclined surfaces forming ramps, a rod longitudinaily disposed in said tube, at least one group of inclined surfaces providing cams formed on a wedgeshaped block which has a transverse aperture, one end of said rod being screw-threaded and screw-threadedly engaged in a threaded opening at the smaller end of said wedge block, whereby said block is mounted on said rod and longitudinally movable relative to the latter and to said shells, said group of cams being adapted, when moving relative to said shells, to co-operate with said group of ramps so as to effect an expansion of said shells, the latter further comprising guide and connecting means constituted by projections having a transverse base extending from the inner face of said shells radially relative to said tube and protruding into said aperture, said rod being capable of protruding longitudinally at one of its ends into said aperture and bearing against said guide and connecting means, the other end of said rod being screw-threaded, a nut engaged on said other rod end, means for maintaining said nut rigid with said rod end as concerns rotational movement so long as a pre-determined rotational force exerted on the rod is not exceeded, whereby when said rod bears against said guide means, said means for maintaining said nut will become inactive and said nut will move said rod and wedge relative to said tube to further expand it.

3. Anchoring device comprising separate shells assembled so as to form a segmented tube and provided with at least one group of inclined surfaces forming ramps, a rod longitudinally disposed in said tube, at least one group of inclined surfaces providing cams formed on a wedgeshaped block which has a transverse aperture, one end of said rod being screw-threaded and screw-threadedly engaged in a threaded opening at the smaller end of said wedge block, whereby said block is mounted on said rod and longitudinally movable relative to the latter and to said shells, said group of cams being adapted, when moving relative to said shells, to co-operate with said group of ramps so as to effect an expansion of said shells, the latter further comprising guide means constituted by projections having a transverse base extending from the inner face of said shells radially relative to said tube and protruding into said aperture, said rod being capable of protruding longitudinally at one of its ends into said aperture and bearing against said guide means, the other end of said rod being screw-threaded, a nut engaged on said other rod end, the thread of said nut being incomplete, whereby when said rod bears against said guide means said nut thread will be completed by said rod thread and said nut will move said rod and wedge relative to said tube to further expand it.

4. Anchoring device comprising separate shells assembled so as to form a segmented tube and provided with at least one group of inclined surfaces forming ramps, a rod longitudinally disposed in said tube, at least one group of inclined surfaces providing cams formed on a wedgeshaped block which has a transverse aperture, one end of said rod being screw-threaded and screw-threadedly engaged in a threaded opening at the smaller end of said Wedge block, whereby said block is mounted on said rod and longitudinally movable relative to the latter and to said shells, said group of cams being adapted, when moving relative to said shells, to co-operate with said group of ramps so as to effect an expansion of said shells, the

latter further comprising guide and connecting means constituted by hollow projections having a transverse base extending from the inner face of said shells radially relative to said tube and protruding into said aperture and an element extending through said transverse bases and having headed ends normally spaced from said bases and positioned in said hollow projections without projecting externally of the shells and extending through said aperture, said rod being capable of protruding longitudinally at one of its ends into said aperture and bearing against said guide and connecting means, the other end of said rod being screw-threaded, a nut engaged on said other rod end, the thread of said nut being incomplete, whereby when said rod bears against said guide and connecting means said nut thread will be completed by said rod thread and said nut will move said rod and wedge relative to said tube to further expand it.

5. Anchoring device as claimed in claim 4, wherein said one end of said rod comprises a longitudinal extension, whose length is adjustable and through which said one end of said rod is capable of bearing against said guide and connecting means.

6. Anchoring device as claimed in claim 5, wherein one end of said longitudinal extension is screw-threaded and screw-threadedly engaged in a threaded opening at said one end of said rod.

References Cited in the file of this patent UNITED STATES PATENTS 529,742 Meriwether Nov. 27, 1894 1,033,447 Mower July 23, 1912 1,420,532 Edwards June 20, 1922 1,960,405 Amor May 29, 1934 2,028,328 Herold Jan. 21, 1936 2,207,009 Hocher July 9, 1940 2,241,343 Fleaca May 6, 1941 2,774,273 Olson Dec. 18, 1956 FOREIGN PATENTS 515,957 Canada Aug. 23, 1955 754,482 Great Britain Aug. 8, 1956

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