GB2051995A

GB2051995A - Wall plug

Info

Publication number: GB2051995A
Application number: GB7923317A
Authority: GB
Original assignee: COUPE R
Current assignee: COUPE R
Priority date: 1979-07-04
Filing date: 1979-07-04
Publication date: 1981-01-21

Abstract

A wall plug having a cylindrical body portion 10 and a tapering nose portion 12 each of which has a diametrical slot 20, 22 therethrough, the slots being arranged at 90 DEG to each other, wherein plate-like extension members 30 are hingedly attached to the plug so that they can be accommodated in the body slot 20 when the plug is inserted into a hole in a wall and pushed out of the slot to engage the wall when a screw nail is driven into a central passage 16 in the plug. <IMAGE>

Description

SPECIFICATION Improvements in or relating to wall plugs The present invention concerns improvements in or relating to wall plugs, especially but not exclusively wall plugs for use in soft walling materials, for example breeze blocks, plaster board, etc.

A problem associated with the use of standard plastics material wall plugs in walls of certain materials, for example breeze blocks, is that the plug tends to pull out of the wall as the frictional resistance to axial movement thereof is low. A further problem is that owing to the soft nature of the wall the plug's resistance to turning with the screw relative to the wall is considerably reduced.

It is an object of the present invention to obviate or mitigate these disadvantages.

According to the present invention there is provided a wall plug having a body with at least one longitudinally extending slot therein and a plate-like extension member associated with the or each slot attached to the plug the dimensions of said member or members and the location thereof being such that it or they can be accommodated in the associated slot.

Preferably the slot is diametrical and there are two extension members.

Preferably the body and the extension members are injection moulded in one piece from plastics material. The attachment of the extension member to the surface of the wall plug may be by a thin fillet which acts as a hinge and which may extend rearwardly of its point of attachment to the body and said extension member is attached to said fillet extension.

An edge of the extension member is preferably angled and substantially coincident with the outer surface of the wall plug when the member is in an outer position. The edge of the plate-like member opposite the fillet extension is preferably parallel thereto and the dimension between the fillet extension and said edge is preferably slightly less than the radius of the body such that the two diametrically opposed extensions can be accommodated within the slot.

A cut-out-portion may be provided the junction between the said opposite edge and the rear edge of the member.

An inwardly tapering passage is provided in the body for the reception of the screw and so that screws of a different diameter can be accommodated the passage may be provided with longitudinally extending inwardly projecting ribs.

To enhance the grip of the plug on the surrounding wail pyramidal protrusions may be formed on its surfac.

Preferably the plug body has a converging nose portion and a substantially cylindrical portion, the fillet being located substantially at the junction between the said portions, the said diametrical slot being formed in said cylindrical portion and a further diametrical slot being formed in said converging portion, this slot being arranged at 900 to the said slot.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings, in which: Fig. 1 shows a perspective view of a wall plug; and Fig. 2 shows a side elevation of a wall plug in a hole in a wall.

A wall plug injection moulded from plastics material comprises a body having a cylindrical portion 10 and a tapering end portion 12, the cylindrical portion 10 having a flanged end 14.

The cylindrical portion 10 is provided with an inwardly tapering central passage 1 6 which terminates approximately in the area of the junction between the cylindrical and tapered portion 10, 12 of the plug and a plurality of inwardly extending ridges 1 8 are formed in the passage. The cylindrical portion is provided with two longitudinally extending diametrically opposed slots 20 extending from the surface to the passage, the slots terminating short of the junction between the portions 1 0, 12.

A longitudinally extending slot 22 extending diametrically across the tapered portion 12 is arranged at 900 to the plane of the slot 20 and extends over the tapered portion 1 2 and a small portion of the cylindrical portion 1 0. Pyramidal protrusions 24 are formed on the external surface of the tapered portion 12.

An external fillet 26 of substantially triangular cross-section is formed on the surface of the cylindrical portion 10 of the plug in line with and extending from the termination of the slots 20, one fillet 26 being provided at each slot. Each fillet 26 is provided with an extension 28 and on the face of the fillet extension 28 adjacent the cylindrical portion of the plug there is attached a piate-like wing member 30 having a first inner angied edge 32 which normally lies co-incident with the surface of the cylindrical portion of the plug, and edge 34 substantially parallel to and opposite the fillet extension 28 and an end edge 36 at right angles to said edge 34. A cut-out 38 is provided at the junction between the edges 34 and 36.

Two longitudinally extending ridges 40 are provided on the outer surface of the cylindrical portion 10 of the plug, the ridges extending from the flange 14 and having triangular cross-sections.

The thickness of the wing 30 is equal to or less than the width of its associated slot 20 such that by deforming the fillet extension 26 the wing can be pushed into the slot, both wings being accommodated within the plug body as a result of their transverse dimensions.

In use the plug is used in a manner similar to a normal plastics wall plug, that is an appropriately sized hole is drilled in a wall to be plugged, normally a wail of soft material for example breeze block, the plug is pushed into the hole tapered portion 1 2 first and owing to the swept back configuration of the members 30 and fillet extensions 28, continued movement of the plug into the hole forces the wings into the appropriate slots 20 such that the plug assumes a substantially circular cross-section and can readily be fully inserted into the hole until the flange 14 abuts the outer surface of the wall being plugged.

A screw-naii is then inserted into the passage 16 the threads of the screw gripping with the ridges 18 which permit screws of differing diameters to be used with the same diameter wall plug. When the leading end of the screw meets with the cut-out 38 in the members 30 its threads begin to engage the members 30 and further rotation of the screw causing deeper penetration into the plug and forces the members outwardly to a position intermediate the position shown in dotted lines in Fig. 2 and that shown in full lines in Fig. 2.The members 30 are thus forced into the soft material of the wall surrounding the hole and prevent axial movement and rotation of the plug relative to the hole, further penetration of the screw causing the tapered end portion to deform outwardly away from the slot 22 such that its outer surface and especially the pyramidal protrusions 24 engage the internal surface of the hole to enhance the grip of the plug. The ridges 40 on the outer surface of the body portion serve to hold the plug against rotation especially during the initial stages of screw insertion. that is before the wings are forced outwardly.

Various modifications can be made without departing from the scope of the invention. For example it will be readily appreciated that additional slots 20 and 22 and additional members 30 can be provided, one for each additional slot 20. The number and dimensions of the ridges 1 8 can be modified as can the number and design of the protrusions 24 from the tapered portion of the plug.

It will be realised that if the plug is used on a hard wall the members 30 will be prevented from moving outwardly of the plug body but this will serve to increase the efficiency of the plug as it causes an increase in the concentration of the material between the screw and the plug which in turn increases the efficiency of the plug's grip on the wall.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to whether or not particular emphasis has been placed thereon.

Claims

1. A wall plug having a body with at least one longitudinally extending slot therein and a platelike extension member associated with the or each slot attached to the plug, the dimensions of said member or members and the location thereof being such that it or they can be accommodated in the associated slot.

2. A wall plug as claimed in claim 1, in which the slot is diametrical.

3. A wall plug as claimed in claim 1 or claim 2, in which there are two extension members.

4. A wall plug as claimed in claim 1 to 3, in which the body and the extension members are injection moulded in one piece from plastics material.

5. A wall plug as claimed in any one of claims 1 to 4, in which the attachment of the extension member to the surface of the wall plug is by a thin fillet which acts as a hinge.

6. A wall plug as claimed in claim 5, in which the fillet extends rearwardly of its point of attachment to the body and said extension member is attached to said fillet extension.

7. A wall plug as claimed in claim 6, in which the edge of the extension member opposite the fillet extension is parallel thereto.

8. A wall plug as claimed in claim 7, in which the dimension between the fillet extension and said edge is slightly less than the radius of the body such that the two diametrically opposed extensions can be accommodated within the slot.

9. A wall plug as claimed in claim 7 or claim 8, in which a cut-out portion is provided the junction between the said opposite edge and the rear edge of the member.

10. A wall plug as claimed in any one of the preceding claims, in which an inwardly tapering passage is provided in the body for the reception of the screw.

11. A wall plug as claimed in claim 10, in which the passage is provided with longitudinally extending inwardly projecting ribs.

12. A wall plug as claimed in any one of the preceding claims in which pyramidal protrusions are formed on the external surface of the plug.

13. A wall plug as claimed in any one of the preceding claims, in which the plug body has a converging nose portion and a substantially cylindrical body portion.

14. A wall plug as claimed in claim 13, in which the fillet is located substantially at the junction between the said nose and body portions.

15. A wall plug as claimed in claim 13 or claim 14, in which the said diametrical slot is formed in said cylindrical portion and a further diametrical slot is formed in said converging portion, this slot being arranged at 900 to the said slot.

1 6. A wall plug substantially as hereinbefore described with reference to the accompanying drawings.

1 7. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scop of or relating to the same invention as any of the preceding claims.