GB2289737A

GB2289737A - Anchor system

Info

Publication number: GB2289737A
Application number: GB9510601A
Authority: GB
Inventors: Sylvester Liem
Original assignee: ITW Construction Systems Australia Pty Ltd
Current assignee: ITW Construction Systems Australia Pty Ltd
Priority date: 1994-05-25
Filing date: 1995-05-25
Publication date: 1995-11-29
Also published as: GB9510601D0; NZ272159A; AUPM587694A0

Abstract

A chemically-set anchor system comprises a female anchor (2) with an internally beaded bore, a capsule (not shown) containing resin and a hardener, and a setting tool (4) which fits into the bore in the anchor (2). The capsule and anchor are inserted into a hole drilled into masonry, and the setting tool (4) is coupled to the anchor (2) by a connection (14, 16) which permits torque to be transmitted from the tool (4) to the anchor (2) whereby rotation of the anchor (2) breaks the capsule and mixes the resin and hardener. The connection (14, 16) is such that the setting tool can then be withdrawn from the anchor by simple axial movement without applying torque to the anchor (2), and without waiting for the adhesive to harden. The connection may be a drive pin (14) on the tool (4) engaging slots (16) in the anchor (2), or vice versa. Alternatively, the bore of the anchor (2) may be a square or hexagonal in cross-section, for engagement by a corresponding profile on the tool (4). The free end of the shank (12) may carry a spring clip (not shown) to frictionally hold the anchor (2) on the tool (4). <IMAGE>

Description

CHEMICALLY-SETANC:HOR SYSTEM The present invention relates to an anchor system of the type comprising an internally threaded (female) anchor which is set within a hole drilled into masonry by means of a hardenable adhesive. An anchor system of this type is commonly known as a chemically-set system.

A conventional chemicallyiet system of the type specified above comprises an internally threaded cylindrical anchor and a glass capsule consisting of a two-part adhesive, for example vinylester resin and hardener. The capsule is inserted into the bottom of the hole and then the anchor is inserted into the hole. The anchor is then driven further into the hole and is rotated in order to break the capsule, mix the components and cause the mixture to extrude rearwardly along the bolt of the anchor to thereby form a bond between the anchor and the wall of the hole. The setting action is achieved by means of a threaded setting tool having a shank which is screwed into the threaded bore of the anchor and a hexagonal head which can be mounted within a hexagonal socket mounted within the chuck of an electric drill which may be a hammer drill.The drill is actuated to cause rotation of the anchor, and the anchor, whilst being rotated, is pushed deeper into the hole by applying pressure to the drill. When the anchor has been set fully into the hole, the socket is disengaged from the head of the setting tool and the adhesive mixture is allowed to set and this may take up to half an hour or even longer depending on the ambient temperature. The setting tool is subsequently removed by unscrewing the tool from the anchor. With this type of system the setting tool cannot be removed until the adhesive has set at which time the anchor will be in a condition to withstand the release torque which must be applied to the setting tool to remove the tool.This means that not only must an installer maintain a large stock of setting tools to enable a series of anchors to be installed at the same time, but also the site of installation must be revisited some time after installation of the anchor in order to remove the setting tool. This can cause considerable inconvenience, particularly if the anchor is installed in a relatively inaccessible position.

According to the present invention, there is provided an anchor system comprising a female anchor adapted to be inserted into a hole drilled into masonry, said anchor including an internal bore, a capsule of hardenable adhesive formed by components which mix together when the capsule is broken, the capsule being insertable into the base of the hole such that the capsule will be broken and the components mixed when the anchor is thrust into the hole with rotation, and a tool for setting the anchor within the hole, said tool and anchor having interengaging coupling means which couple the anchor to the tool for rotation therewith and which can be disengaged by withdrawing the tool axially from the anchor when the anchor is set within the hole and without applying torque to the anchor.

In a preferred embodiment of the invention the coupling means may comprise one or more projections or slots on the tool engage able with corresponding slots or projections at the outer end portion of the anchor. Alternatively, the internal bore of the anchor may have at its outer end portion a cross-sectional shape of noncircular form, for example square or hexagonal to receive a correspondingly shaped part of the tool. Irrespective of the precise form of the connection, engagement and disengagement of the anchor relative to the tool is effected by a simple axial movement of one relative to the other whereby after setting of the anchor within the hole the tool can be immediately withdrawn without applying torque to the anchor and without waiting for the adhesive to harden.

Preferably, the setting tool includes an elongate shank having a substantial depth of extension into the bore of the anchor, the shank preferably including a spring clip or other means whereby the anchor can be held to the tool without falling off during handling.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view showing the outer end portion of the anchor and a setting tool; and Figure 2 shows schematically a capsule containing adhesive and hardener.

The anchor system in accordance with the preferred embodiment of the invention comprises an internally threaded, or female, anchor 2, a setting tool 4, and a capsule 6 of glass containing an adhesive 8 such as vinylester resin, and a hardener 10 contained separately within the capsule. Apart from the design of the anchor 2 at its outer end, the design of the anchor 2 is substantially conventional. The anchor 2 has at its inner end (not shown) a chisel point which is effective to break the capsule 6 and cause intermixing of the components.

The setting tool 4 comprises a shank 12 of a diameter to fit closely within the internally-threaded bore of the anchor 2. It is to be noted that the shank 12 is not threaded so as to screw into the threaded bore but is, instead, a sliding fit. A transverse pin 14 is carried at the distal end of the shank 12 so that the opposed end portions of the pin project from opposite sides of the shank 12. When the shank 12 is inserted into the outer end of the anchor the projecting end portions of the pin 14 engage within opposed slots 16 formed axially in the anchor and opening onto the outer end face 17 of the anchor. Beyond the pin 14 the tool is stepped outwardly to a larger diameter portion 18 having an outer diameter substantially equal to that of the anchor body.The outer end of the tool forms a driving head 20 which is configured to mate with a drive member carried within the chuck of a drill. As shown the head 20 is formed with a female driving socket 22 adapted to receive a male driving member within the drill chuck, but alternatively the external surface of the head 20 may be of square or hexagonal section to fit within a female driving socket mounted within the drill chuck. The outwards stepping of the tool beyond the pin 14 forms an axial thrust shoulder 24 which engages against the outer end face 17 of the anchor when the shank 12 has been inserted into the anchor with the end portions of the pin 14 engaged with the slots 16 in the anchor whereby to form a rotational connection between the tool 4 and anchor 2 with subsequent release being effected by simple axial withdrawal of the tool 4.

To set the anchor, the capsule 6 is inserted into the hole and then the anchor 2 is driven into the hole by means of the setting tool 4 which rotationally engages with the anchor to rotate the anchor 2 and drive the anchor 2 deeper into the hole to break the capsule 6, cause intermixing of the components 8,10 and extrusion of the mixture between the outer surface of the anchor 2 and the wall of the hole, axial thrust being applied to the anchor through the engagement of the shoulder 24 with the end face 17 of the anchor 2. When the anchor has been inserted to the required depth the setting tool 4 can be axially withdrawn from the anchor 2 without applying any torque to the anchor 2 and hence without disturbing the setting of the anchor 2.Therefore the setting tool 4 can be withdrawn immediately after the anchor 2 has been set to the required depth and without waiting for the adhesive to harden.

Accordingly only a single setting tool will be required and, more importantly, the installer will not need to revisit the site of the installation to remove the setting tool.

Although as described the driving connection between the setting tool 4 and the anchor 2 is achieved by means of a transverse pin on the tool engaged within axial slots at the outer end of the anchor 2, other means capable of providing a driving connection with axial release could alternatively be used. For example the bore of the anchor 2 could be formed at its outer end portion with a square, hexagonal, or other non-circular profile to mate with a surface of corresponding profile formed on the exterior of the setting tool 4.

It will be noted that while the extension of the shank 12 beyond the zone of rotational driving engagement between the setting tool 4 and anchor 2 is not essential to effect setting of the anchor, it is desirable as the substantial penetration of the shank 12 of the setting tool 4 into the bore of the anchor 2 facilitates correct centring of the anchor 2 within the hole. Also this portion of the shank preferably carries a spring clip (not shown) which frictionally engages with the threaded bore of the anchor 2 to prevent the anchor 2 from falling from the setting tool prior to insertion into the hole. The coupling between the setting tool 4 and the driving member within the drill bit is advantageously such that the setting tool 4 cannot accidentally fall from the driving member and accordingly setting of the anchor 2 can be quickly achieved by mounting the anchor 2 on the shank 12 of the setting tool 4, with the spring clip ensuring that the anchor 2 is held sufficiently to the tool 4 to prevent the anchor 2 from falling from the tool 4, and then inserting the anchor 2 into the hole by appropriate movement of the drill. The enlargement of the setting tool 4 outwardly of the pin 14 to a diameter substantially equal to the external diameter of the anchor to provide the thrust shoulder 24 enables the anchor 2 to be set into the hole below the surface of the masonry.

The embodiment has been described by way of example only and modifications are possible within the scope of the invention.

Claims

CLAIMS:

1. An anchor system comprising a female anchor adapted to be inserted into a hole drilled into masonry, said anchor including an internal bore, a capsule of hardenable adhesive formed by components which mix together when the capsule is broken, the capsule being insertable into the base of the hole such that the capsule will be broken and the components mixed when the anchor is thrust into the hole with rotation, and a tool for setting the anchor within the hole, said tool and anchor having interengaging coupling means which couple the anchor to the tool for rotation therewith and which can be disengaged by withdrawing the tool axially from the anchor when the anchor is set within the hole and without applying torque to the anchor.

2. An anchor system according to claim 1, wherein the coupling means comprise at least one projection or slot on the tool engageable with a corresponding slot or projection at the outer end portion of the anchor.

3. An anchor system according to claim 2, wherein the coupling means comprise at least two angularly spaced slots in the anchor extending axially from the outer end edge of the anchor, and at least two angularly spaced projections on the tool and engageable with the slots.

4. An anchor system according to claim 1, wherein the internal bore of the anchor has at its outer end portion a cross-sectional shape of non-circular form, to receive a correspondingly-shaped part of the tool, said bore portion and said part of the tool forming said interengaging coupling means.

5. An anchor system according to any one of claims 1 to 4, wherein the tool includes an elongate shank having a substantial depth of extension into the bore of the anchor.

6. An anchor system according to claim 5, wherein the shank of the tool includes means for holding the anchor to the tool such that the anchor will not fall from the tool during handling.

7. An anchor system substantially as hereinbefore described with reference to the accompanying drawings.