GB2215420A - Wall anchors - Google Patents

Abstract

A one-piece wall anchor for fixing to a hollow wall comprises a head 2 adapted to engage the outer surface of the wall, an elongate arm 8 adapted to engage the inner surface of the wall, and a hooked portion 10 connecting the arm to the head to enable the arm to be fed through a hole in the wall by orientating the anchor so that the arm can pass into the hole, substantially in the direction of its longitudinal axis, the anchor then being progressively tilted so as to move the arm and the head into approximately parallel relation with the outer and inner surfaces of the wall. The arm 8 is adapted for screw-threaded engagement with a screw passing through the head 3 to draw the arm into firm engagement with the inner surface of the wall. The head 2 includes radial tangs 20a engageable into the outer surface of the wall to prevent rotation of the anchor during tightening of the screw. <IMAGE>

Description

"WALL ANCHORS" The present invention relates to wall anchors, and more particularly to wall anchors for fixing to a hollow wall such as a wall formed by a panel of plasterboard.

Wall anchors for use with hollow plasterboard walls conventionally include a toggle which is pushed into the wall with the toggle collapsed, the toggle then expanding within the hollow interior of the wall to prevent subsequent withdrawal of the anchor. Toggle-type anchors of this nature are frequently formed in one-piece from plastics and the toggles do not always expand to an extent necessary to hold the anchor firmly within the wall. Toggle-type anchors with separate spring-loaded wings are also well known and while these anchors perform satisfactorily, they are relatively expensive to produce.

According to the present invention, there is provided a wall anchor for fixing to a hollow wall comprising a head portion adapted to engage the outer surface of the wall, an elongate fixing portion adapted to engage the inner surface of the wall, means connecting the fixing portion to the head portion to enable the fixing portion to be fed through a hole in the wall by orientating the anchor so that the fixing portion can pass into the hole, substantially in the direction of the longitudinal axis of the fixing portion, the anchor then being progressively tilted so as to move the fixing portion and the head portion into approximately parallel relation with the outer and inner surfaces of the wall, the fixing portion being adapted for screw-threaded engagement with a screw passing through the head portion to draw the fixing portion into firm engagement with the inner surface of the panel, and the head portion including means engageable into the outer surface of the panel to prevent rotation of the anchor during tightening of the screw.

Preferably, the fixing portion is so shaped as to prevent bending of the fixing portion during tightening of the screw.

In a preferred embodiment, the rotationpreventing means comprises tangs orientated approximately radially with respect to the axis of the screw, and the fixing portion is formed into a shallow channel to prevent bending.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure l-is a perspective view of an anchor in accordance with the invention; Figure 2 is a section showning the anchor after intention into a wall panel; and Figure 3 is a section similar to Figure 2 but showing the anchor after tightening.

The wall anchor shown in the drawings is of hook-like form having a head portion 2 consisting of a plate 3 which lies flush against the outer surface of a wall panel 4. A leg 6 extends perpendicuarly from the plate 3 at a position intermediate the sides and ends of the plate, and carries at its remote end a fixing portion 8. The length of the leg 6 corresponds to the thickness of the wall panel 4 so that the fixing portion 8 will lie at the inner surface of the panel. The fixing portion 8 comprises a deformable, curved, hooking section 10 which merges with an arm 12 of substantially rectilinear form and which faces the head portion 2 at the opposite end of the anchor.

The plate 3 has an aperture 14 to receive a fastening screw 16 and the arm 12 includes an opening 18 of a form which provides threaded engagement with the screw 16, the opening 18 being aligned with the aperture 14. The plate 3 includes inwardly-directed tangs 20, 20a perpendicular to the plane of the plate to bite into the outer surface of the panel 4 to secure the anchor while the screw is being inserted and the article to be fixed is being positioned. In order to prevent the anchor from rotating during tightening of the screw, at least some of the tangs are so orientated that the major surfaces of the tangs extend approximately radially with respect to the screw 16, so as to provide a large bearing surface which resists rotation under the influence of the torque generated by the screw upon tightening.In the embodiment shown, the tangs 20a are orientated approximately radially while the tangs 20 are orientated in a tangental direction normal to the radial direction. These latter tangs are orientated tangentially to simplify fabrication of the anchor and the two radial tangs 20a will act to provide a sufficient torque-resisting effect. As may be apparent, if all of the tangs were tangentially orientated, the edges of the tangs could simply trepan a groove around the hole in the panel during tightening. It is also to be noted that while it is desirable for the radial tangs to be orientated as closely as possible to the radial direction to provide maximum torque resistance, it is not essential that the tangs are placed in precise radial orientation.Primarily, what is necessary is that the tangs are so arranged that a substantial surface component of the tang faces in such a direction as to resist rotation of the anchor.

The arm 12 of the fixing portion 8 is shaped to resist bending about a transverse axis particularly in the area of the screw opening 18 and this is preferably achieved by forming the arm 12 with a concave transverse cross-section which also facilitates location of the end of the screw into the opening 18. Preferably, the width (d) of the arm 12 is approximately equal to the diameter of the hole formed in the panel 4, and the length of the arm is from 4d to 8d. This relationship has been found to provide good bearing characteristics while enabling easy insertion of the anchor through the hole in the panel 4.

In order to fix the anchor, a hole is drilled into the panel 4 and the arm 12 is inserted end-on into the hole. As the arm 12 is fed through the hole, the anchor is progressively tilted so that the arm 12 moves into approximately parallel relationship with the rear face of the panel 4, this movement being facilitated by the curved hooking section 10 which is of a diameter approximately equal to the panel thickness. As shown in Figure 2, when the anchor is properly orientated, the tangs 20, 20a of the head portion 2 may be pushed into the panel, or alternatively this may occur automatically during tightening of the screw. The screw 16 is then inserted through the article to be fixed and into the anchor so that the end of the screw engages into the threaded opening 18 in the arm 12.As the screw 16 is tightened, the arm 12 is drawn progressively towards the rear surface of the panel 4, the hooking section 10 deforming to permit this movement. Final tightening of the screw 16 draws the arm into tight engagement with the panel surface as shown in Figure 3. Due to its shape, the arm 12 will not bend transversely under the forces of the tightened screw despite the reduced cross-sectional area in the zone of the screw opening and therefore constitutes a rigid bearing member for the screw, within the wall.

The anchor itself will remain firmly attached to the wall even upon subsequent removal of the screw.

The anchor may be formed in one piece by stamping or pressing from metal strip and may be appropriately heat treated to permit the necessary deformation of the hooking section 10.

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

Claims (8)

1. A wall anchor for fixing to a hollow wall comprising a head portion adapted to engage the outer surface of the wall, an elongate fixing portion adapted to engage the inner surface of the wall, means connecting the fixing portion to the head portion to enable the fixing portion to be fed through a hole in the wall by orientating the anchor so that the fixing portion can pass into the hole, substantially in the direction of the longitudinal axis of the fixing portion, the anchor then being progressively tilted so as to move the fixing portion and the head portion into approximately parallel relation with the outer and inner surfaces of the wall, the fixing portion being adapted for screw-threaded engagement with a screw passing through the head portion to draw the fixing portion into firm engagement with the inner surface of the panel, and the head portion including means engageable into the outer surface of the panel to prevent rotation of the anchor during tightening of the screw.

2. A wall anchor according to claim 1, wherein the means engageable into the outer surface of the panel to prevent rotation comprises at least one tang extending from the head portion, and being orientated approximately radially with respect to the axis of the screw.

3. A wall anchor according to claim 2, wherein the head portion comprises a plate arranged to lie flush against the outer surface of the wall, and the or each tang extends perpendicularly to the plane of the plate.

4. A wall anchor according to any one of claims 1 to 3, wherein the connecting means comprises a deformable curved hooking section which merges with the fixing portion, said fixing portion comprising an arm of substantially rectilinear form.

5. A wall anchor according to claim 4, wherein the arm is of channel section to resist bending.

6. A wall anchor according to claim 5, wherein the arm includes an opening of a form which provides threaded engagement with the fastening screw, said arm being of concave section in a direction facing towards the head, with the opening being in the base of the concave section.

7. A wall anchor according to any preceding claim, wherein the anchor is formed in one piece by stamping or pressing from metal strip.

8. A wall anchor substantially as hereinbefore described with reference to the accompanying drawings.