GB2154687A - Securing elongate elements within openings - Google Patents

Abstract

A locking device for securing an elongate element (22;110;210) such as a rod of a wall tie in an opening (15;114;214), comprises an abutment (25;125;225), a locking part (26;160;260) and at least one locking ring (27-29; 128;230), the locking ring being positioned between the locking part (26;160;260) and the abutment (25;125;225), the locking ring having a plurality of fingers (30;130;230) extending radially outwardly of the element towards the other end (22;122) of the element, and engaging the abutment, the locking part (26;160;266) being movable towards the abutment to reduce the separation therebetween and to cause the fingers (30;130;230) of the locking ring to move further outwardly into engagement with the inside surface (50;150;250) of the opening, the locking part having means such as a threaded engagement or tangs (T,T') to resist axial movement of the locking part away from the abutment. <IMAGE>

Description

SPECIFICATION Locking device for an elongate element This invention relates to a locking device for securing an elongate element within an opening in a structure and more particularly, but not exclusively, to a locking device for securing an elongate element comprising a wall tie, in an opening. However, the invention may be used to secure other elongate elements such as screws or bolts which are used to attach articles such as brackets to a surface of a structure, which brackets may be used to support shelves or the like. Alternatively, such elongate elements comprise studding to which articles are attached, spaced from the surface of the structure, which studs or other elongate elements may be used to rest articles such as shelves thereon directly.

Original wall ties, i.e. those which are secured in position by the bricklayer during the original construction of a cavity wall structure, tend in time to rust through due to the presence of moisture in the cavity, and the inner and outer walls thus become relatively movable. To prevent the building collapsing, it is necessary to secure new wall ties in position.

In the past, because access cannot be gained to the cavity, it has been necessary to dismantle the inner, or more usually outer, wall, secure new ties in position and reconstruct the inner or outer wall. This is obviously costly, time consuming and very inconvenient.

More recently, remedial wall ties have been developed which can be located in position without the need to dismantle either the inner or the outer wall. An opening is bored through, usually the outer wall for each tie, into the inner wall but usually not extending through the inner wall. The tie is then passed through the bore in the outer wall, an inner end of the tie extending into a blind bore in the inner wall and being provided with a device to lock the inner end of the wall tie in the blind bore in the innerl wall. The outer end of the wall tie is then secured relative to the outer wall.

In other applications, such as securing an elongate element, such as a screw within an opening in a structure such as, for example, a masonry wall, the usual method of securing the screw is to plug the opening with an insert and insert a screw threaded end of the screw by rotation, into the insert. The insert expands and hence frictionally grips the inside surface of the opening and prevents withdrawal of the elongate element.

Where studding is concerned, it is at present necessary to fix the studding in position, with for example cement, the cement trapping an abutment such as a hook, to prevent withdrawal.

It is an object of the resent invention to provide a new or improved locking device for securing an elongate element within an opening in a structure.

According to one aspect of the invention, we provide a locking device for securing an elongate element in an opening, the device comprising an abutment, a locking part, and at least one locking ring, the locking ring being positioned inwardly of the end of the element between the locking part which is outermost, and the abutment, the locking ring having a plurality of fingers extending radially outwardly of the element towards the other end of the element, and engaging the abutment, the locking part being movable towards the abutment to reduce the separation therebetween and to cause the fingers of the locking ring to move further outwardly into engagement with the inside surface of the opening, the locking part having means to resist axial movement of the locking part away from the abutment.

Such an arrangement provides a more versatile locking device than those hitherto used and may be ued to secure the elongate element in a wide variety of structures. This is achieved because the fingers extend both radially outwardly of the axis of the element and towards said other end. In soft materials, the fingers can thus dig into the surface of the opening, whereas in harder materials, the fingers can dig in and/or provide adequate friction, to resist high withdrawal forces.

In one embodiment, the locking part and locking ring are separate, whereas in another embodiment the locking part and locking ring are provided as an integral assembly. The abutment may be separate from but secured relative to the elongate element, or may be provided by an integral part thereof. For example, the one end of the element may be threaded and the abutment may comprise a nut screwed thereon to a predetermined position along the element. The locking part may in this instance comprisd a nut or other female threaded part movable towards the abutment upon relative rotation between the female threaded part and the element. Axial movement of the nut or other female threaded part along the rod towards said one end would be due to the engagement of the threads of the nut and the element.In this case, means are preferably provided, such as washers, to facilitate relative rotation between the locking ring whose fingers are engaged with the inside wall of the opening and the abutment and a locking member may be provided to lock the locking part against rotation with the element.

In another embodiment, the locking part may comprise a collar substantially surrounding the elongate element, the collar being movable axially of the element towards the abutment to reduce the separation therebetween. Axial movement of the collar along the rod towards said one end may be resisted by one or more tangs integral with the collar or provided on a separate element which tangs extend towards the axis of the elongate element and engage the surface thereof.

Preferably the tangs extend in a direction away from the abutment to provide maximum resistance to movement of the locking part away from the abutment, and if necessary the elongate element may have one or more grooves therein, in which the tangs locate to provide further resistance to said axial movement.

In this case, no locking member would be required to prevent relative rotation between the locking part and the elongate element, as a decrease in the separation between the locking part and the abutment may be achieved purely by axial movement of the rod relative to the locking part.

In either embodiment the or each of the fingers of the locking ring may be made of a material such as plastics or soft metal which is malleable so that as the fingers are urged outwardly they become deformed making withdrawal of the element from the opening increasingly difficult.

The fingers may comprise a splayed end of the locking ring separated by slits cut axially of the ring, the splayed end decreasing in cross-sectional area along the ring, the outermost edges of the fingers providing abutment portions which engage i.e. frictionally engage and/or dig into the inside surface of the opening.

The locking device may comprise a plurality of such locking rings, each having an end opposite to its splayed end radially smaller than the splayed end of the next locking ring nearest the locking part, so that said opposite ends of the rings engage the fingers directly or through one or more intermediate members, such as one or more washers, to urge the fingers outwardly as the separation between the abutment and the locking part is reduced. The locking part may engage said opposite end of the or the nearest locking ring directly or through one or more intermediate members, or at least one of the locking rings may comprise a locking part integral therewith to resist movement of the locking part and hence locking ring away from the abutment.

The or each intermediate member between the locking rings, where provided, may comprise a plain washer and/or another washer, such as a cup washer, to ensure that the fingers of the locking ring on which the adjacent washer bears, moves uniformly outwardly to provide efficient grip of the inside surface of the opening.

The plain washers and/or the cup washers may be slightly smaller than the inside diameter of the opening so that the fingers of the locking rings do not extend outwardly of the washers until said separation is reduced, when the abutment portions of the fingers may be urged into a small space between the washer and the inside surface of the opening to provide strong resistance to withdrawal.

The elongate element may comprise a rod of a wall tie in which case the opening may be provided in an inner or outer wall of a cavity wall structure, the rod extending through a bore in the outer or inner wall of the structure and through the cavity, into the opening in the inner or outer wall.

The opposite end of the rod in the bore in the outer or inner wall may be secured relative to the outer or inner wall via one or more further locking rings trapped between a further abutment of the rod and a still further locking part, the further locking ring or rings each having a finger or fingers which extend radially outwardly of the axis of the rod, the fingers being urged outwardly into engagement with an inside surface of the opening as the separation between the further locking part and the abutment is reduced.

Where a plurality of rings are provided at said opposite end of the rod, again each locking ring may have an end opposite to a splayed end radially smaller than the splayed end of the next locking ring nearest the further locking part to urge the fingers outwardly, directly although an intermediate member such as again a plain and/or cup washer which act(s) to urge the fingers outwardly, as the further locking part is rotated relative to the rod. The further abutment may engage a further washer which is in turn engaged by the fingers of the nearest further locking ring, to allow relative rotation between the locking ring or rings and the element.

According to a second aspect of the invention, we provide a remedial wall tie having an elongate element comprising a rod, a locking device according to the first aspect of the invention for securing one end of the rod thereof in an opening in the inner or outer wall of a cavity wall structure, and a further locking device according to the first aspect of the invention for securing the opposite end of the rod in a bore in the outer or inner wall structure respectively.

According to a third apect of the invention, we provide a method of securing an elongate element within an opening in a structure, using a locking device according to the first aspect of the invention, said method comprising the steps of moving the locking part relatively towards the abutment to reduce the separation therebetween and to cause the fingers of the locking ring to move outwardly into engagement with the inside surface of the opening, the locking part having means to resist axial movement of the locking part away from the abutment.

The elongate element may be rotated relative to the locking part to reduce the separation between the abutment and the locking part. Alternatively, the elongate element may be moved axially, for example with the aid of a hammer or other striking tool to reduce the separation between the abutment and the locking part.

In the latter embodiment, the elongate element may be secured in the opening in the structure simply by tapping with a hammer or other striking tool; in the former embodiment, it is necessary both to move the elongate element axially into the opening and then to rotate the element relative to the locking part.

In the method according to the third aspect of the invention, the elongate element may be a rod of a wall tie according to the second aspect of the invention.

The invention will now be described with the aid of the accompanying drawings, in which: Figure 1 is a section through a cavity wall structure showing an elongate element comprising a wall tie, secured in an opening by a first embodiment of a locking device in accordance with the invention, the tie and the locking device being shown partly in section, and partly in elevation; Figure 2 is an end view of a locking ring for use in the wall tie of Fig. 1.

Figure 3 is an enlarged view of part of Fig.

1.

Figure 4 is a section through a wall structure showing a stud secured in an opening by a second embodiment of a locking device in accordance with the invention; Figure 5 is a section through a wall structure showing a stud secured in an opening by a third embodiment of a locking device in accordance with the invention.

Referring to Figs. 1 to 3 of the drawings, a cavity wall structure 10 comprises an outer wall 11, an inner wall 1 2 and a cavity 1 3 therebetween. A bore 1 4 extends through the outer wall 11, and a continuation of the bore, indicated at 15, provides an opening which extends into the inner wall 1 2 but is blind, i.e. has a closed end 16.

It will be seen that the closed end 1 6 of the opening is conical due to the drill shape by which the opening was provided. Of course, if desired, the bore 1 4 and/or opening 1 5 need not be drilled, but could be provided by any other method as desired and the opening 1 5 may be closed by an abutment in the opening 1 5 rather than having a closed end 1 6.

Received within the bore 1 4 and opening 1 5 is a wall tie 20 having an elongate element comprising a rod 21, the ends 22 and 23 of which are threaded,the threads extending from the ends 22, 23 inwardly of the rod 21 over a distance generally equal to the length of the bore 14 and opening 1 5 respectively.

The wall tie 20 at the end 23 received within the blind opening 15, is shown in section, whereas the end 22 of the wall tie 20 received within bore 14 is shown in elevation.

In each case, the wall 12, 11 is sectioned.

A nut 25' is screw threadedly received on the end 23 of the rod 21, and provides part of an abutment 25 of the tie with which locking rings, hereinafter described, co-operate.

A further nut 26 comprising a first female threaded locking part is also received on the threaded end 23 of the rod 21.

A plurality, in the example shown three, locking rings 27, 28 and 29 are trapped between the abutment 25 and the female threaded part 26, each of the rings 27, 28, 29, being substantially identical and are described in detail with reference to ring 29 shown in Fig. 2.

A washer W (or washers) and a bush B are interposed between the nut 25' and the adjacent locking ring 27.

The ring 29 comprises a plurality, in the present example six, fingers 30 each being provided by a splayed end 32 of the locking ring, the fingers 30 being separated from one another by slits 33 which extend generally axially of the rod 21 from the edges 35 of the fingers 30 to the unsplayed part 36 of the ring.

In use, the ring 29 substantially completely surrounds the rod 21, although as the ring 29 is fabricated from sheet metal, there is one slit 37 extending along the entire length of the ring 29. If the locking ring 29 was fabricated in another manner or made for example of plastics material, such slit 37 may not be present, or if desired the slit may be closed by adhereing or otherwise permanently securing together the edges of the slit.

The unsplayed end 36 of the ring 29 bears on an intermediate member 40 comprising a washer, on which the locking part 26 directly bears.

The unsplayed end 36' of the next locking ring 28, is radially smaller than the splayed end 32 of locking ring 29 and engages and bears on a cup washer 42 and in turn on plain washer 42' which actually engages the insides of the fingers 30 of ring 29.

Similarly, the unsplayed end 36" of the locking ring 27 is radially smaller than the splayed end of the locking ring 28, and bears on a cup washer 42" and plain washer 42"' in the inside of the fingers 30 of the locking ring 28.

The purpose of the (indentical) plain wash ers 42' and 42"' is to ensure that the fingers of the next locking ring nearest the locking part 26 are urged uniformly outwardly as hereinafter described, to engage the inside surface of the opening 15, and the cup washers 42, 42" provide a double thickness of material of the unsplayed ends of the locking rings to prevent collapse of the locking rings in this region as force is exerted.

The fingers 30 of the locking ring 27 each engate bush B adjacent the nut 25, which nut 25, bus B, and washer W together provide the abutment of the rod 21, so that the locking ring 27 is permitted to rotate relative to the abutment 25.

It will be appreciated that as the locking part 26 is rotated relative to rod 21 (in practice rod 21 is rotated relative to locking part 26) that the distance between the abutment 25 and the locking part 26 will decrease. This will cause the locking rings 27-29 to be urged together so that the edges 35 of each of the fingers 36 of each of the locking rings 27 to 29, are urged outwardly into abutment with the inside surface 50 of the bore 15.

As the fingers 30 of the locking rings 27 to 29 each extend radially outwardly of the axis of the rod 21, and rearwardly away from the locking part 26, a considerable resistive force to withdrawal of the rod 21 from the bore 15 is exerted.

In practice, when the wall tie 20 is inserted into the bore 14 and opening 15, as the locking part 26 is then inaccessible, the rod 21 is rotated relative to the female threaded part 26.

Referring to Fig. 3, an enlarged view of a finger 30 of ring 29 is shown. It can be seen that washer 42' is only slightly smaller in diameter than the opening 1 5 and thus only a small annular space S is left between them.

As the finger 30 and washer 42' are urged together, the outermost edge 35 of the finger 30, which provides an abutment portion, is urged into the space S. To ensure that the maximum outward force is exerted, the angle of the finger 30 to the axis of the rod 21, is preferably about 45". If the material of wall 1 2 is not too hard, the finger 30 will cut into the surface of the opening 1 5 as shown.

Otherwise a tight frictional grip will be achieved.

It will be appreciated that unless the locking part 26 is locked against rotation in the opening 15, the locking part 26 will simply rotate in the opening 1 5 as the rod 21 is rotated, and thus the distance between the locking part 26 and the abutment 25 will not decrease. Hence a locking member 60 is provided to prevent the locking part 26 rotating.

The locking member 60 is of similar configuration to the locking rings 27 to 29 although the unsplayed end 61 thereof is longer.

Upon insertion of the tie 10, the edge 62 of the unsplayed end 61 engages the inside conical surface of the blind end 1 6 of the opening 1 5 to provide engagement between the locking member 60 and the opening 1 5.

Fingers 63 of the locking member 60 each engage a flat of the female threaded part 26 to prevent relative rotation between the female threaded part 26 and the locking member 60 as the rod 21 is rotated.

A further female threaded part 65 is provided radially between the unsplayed end 61 and the rod 21, the part 65 serving to maintain the locking member 60 in correct position during operation.

Operation of the wall tie 20, and in particular the manner in which it becomes locked in the opening 15, will now be described.

Once the opening 1 5 has been provided in wall 1 2, end 23 of the tie 20 is inserted into the opening 1 5 through bore 14. At this point, the fingers 32 and 63 of the locking rings 27 to 29 and locking member 60 are a minimum distance from the axis of the rod 21. Their external dimensions may be slightly greater than the internal dimension of the base 14, opening 15, in which case the locking rings 27 to 29 and locking member 60 may need to be urged along the bore 14/opening 1 5 with the aid of a gentle tap with a hammer although preferably the fingers 30 do not extend outwarly beyond the washers 42', 42"' and W.In any case, when the edge 62 of the locking member 60 engages the conical surface 1 6 of the blind end of the bore, a gentle tapping at the end 22 of the wall tie, will move the locking part 26 axially, relatively inwardly of the splayed end 63 of the locking member 60 and thus cause the fingers 63 of the locking member 60 to move outwardly into abutting engagement with the inside surface 50 of the opening 1 5.

It will be appreciated that the further female threaded part 65 is an interference fit with the unsplayed end 61 of the locking member 60 and thus sliding relative movement is permitted between the two.

This tapping of end 22 will secure the locking member 60 relative to the opening 15, and due to the engagement between the fingers 63 and the locking part 26, the locking part 26 will thus become secured against rotation in the opening 1 5. Thereafter, the rod 21 is rotated by a suitable tool such as a clamp means, engaging the end 22 thereof, this rotation causing the distance between the abutment 25 and locking part 26 to decrease and hence the abutment 25 will be urged towards the splayed end 32 of locking ring 27 which will in turn be urged towards the washers 42", 42"' adjacent the splayed end 52 of locking ring 26 which will in turn be urged towards the washers 42', 42 adjacent the splayed 32 of locking ring 29 so that the fingers 30 of each of the locking rings 27 to 29 will be urged outwardly into increasingly tight abutting engagement with the inside surface 50 of the opening 1 5 as the rod 21 is rotated.

It can be seen from Fig. 2 that the fingers 30 are radiused to give added strength but, being made of sheet material, may tend to deform as they are urged outwardly and become tightly trapped in space S. This defor mation will increase the tightness of engagement between the abutment portions 35 which engage the inside surface 50 of the opening, and the opening 1 5.

The purpose of the washer 40 betwen the unsplayed end 36 of locking ring 29 and nut 26, is to permit relative rotation therebetween as the rod 21 is initially rotated. Rotation of the rod may be controlled by a torque wrench or the like used for rotating the rod 21 so that a predetermined deformation of the fingers 30, and a predetermined resistance to pull out, is obtained.

It will be appreciated that the locking member 60, locking rings 27, 28, 29, washers 42, 42', 42", 42"', and abutment 25 and female threaded parts 26, 65, together provide a locking device to ensure that the tie 20 will be firmly locked in the opening 1 5 against axial withdrawal of the end 23 of the rod 21 from the opening 15.

Preferably, such a wall tie is capable of withstanding a withdrawal force of at least 600 Ibs, and more preferably up to more than 2000 Ibs, provided that the material of the structure in which the opening is provided, is capable of withstanding such withdrawal force.

The end 22 of the rod can be secured relative to wall 11 as follows.

Received on the end 22 of the rod 21 are further locking rings 70, 70', 70" substantially identical to locking ring 29, but the fingers 73 thereof extend radially outwardly of the axis of rod 21 in a direction opposite to the fingers 30 of the locking ring 29.

The fingers 73 of the innermost locking ring 70 engage an abutment 75 comprising a washer 74, bush 74' and an adjacent nut 75'. Thus, the locking ring 70 is pemitted to rotate relative to the nut 75.

The outermost locking ring 70" is engaged through the intermediary of a plain washer 76, with a further female threaded locking part 77 comprising a nut received on the threaded end 22 of the rod 21. Thus, upon rotation of the locking part 77, for example with a socket spanner with a torque wrench, the distance between the locking part 77 and the abutment 75 will decrease, again urging the locking rings 70, 70', 70" together so that their fingers 73 move outwardly into increasingly tight frictional engagement with the inside surface 80 of the bore 14.

It can be seen that the outermost part 91 of the bore 1 4 is enlarged to permit insertion of a socket spanner. Alternatively, the locking part, i.e. nut 77 may be smaller than shown, to permit introduction of a spanner.

Further alternatively, instead of the body part comprising a nut 77, this may comprise a threaded collar, the collar extending beyond the end 22 of the rod 21, the collar having aligned slots in the end thereof to receive a screwdriver bit, for tightening.

Again, plain and cup washers 81, 81' are positioned between pairs of adjacent locking rings 70, 70', 70" to give the advantages hereinbefore described with reference to washers 42, 42', 42", 42"'.

The locking rings 70, 70', 70" and locking part 77 may be received on the end 22 of the wall tie 20 once the other end 23 of the wall tie has been secured in the opening 15, although the entire wall tie is preferably fully assembled ready for locking, before the end 23 is inserted into bore 14/opening 1 5. The locking rings 70, 70' and 70" and washers 74, 76, 81, 81', abutment 75 and locking part 77 together provide a further locking device to secure end 22 of the tie rod in the bore 14.

Within the cavity 13, the rod 21 is provided with a rubber grommet 90 or other transversely extending member to cause any moisture accumulating on the wall tie 20 to drip therefrom into the cavity 13, rather than onto the inside surfaces of the walls 11 and 12.

Preferably the wall tie 20 and locking devices, apart from rubber grommet 90, are entirely made from a rust resistant material, such as a high grade stainless steel, although any other suitable alloy or material giving adequate strength may be provided.

The wall tie 21 is intended to be used as a remedial wall tie, that is for insertion into existing cavity wall structures where the original wall ties have rusted through or otherwise become damaged.

Many modifications may be made to the wall tie described without departing from the scope of the invention. For example, instead of providing cup washers and plain washers and between adjacent pairs of locking rings, if desired the locking rings may be of such configuration that their unsplayed ends can provide a uniform and adequate force, without risk of the unsplayed end collapsing, to the fingers in order to urge them outwardly. In this case, the cup washers and/or plain washers may be omitted.

The further female threaded part 65 provided within the locking member 60 may not be required, where the locking ring 60 is of some alternative self-supporting configuration, or this may be provided integrally with the nut 26.

The abutments 25 and 75 need not be provided by nuts washers and bushes as described, although this is the most convenient, but could be provided by locking collars or outwardly extending integral parts of the rod 21 for examples.

The locking rings need not be of the exact configuration and number described. For example, differing numbers of fingers 30 or 63 may be provided as necessary, or the fingers may be provided with other contours to give strength as necessary, rather than the radius described.

The rod 21 need not be turned by a clamp means to secure the elongate element in the opening 1 5 as described. For example if desired, the end 22 may be slotted to receive a screwdriver bit. The inside surface of bore 14 need not be enlarged at 91 as described, but a special tool to engage the flats of the nut 77 may be used which does not require the additional space.

The invention has been described hereinbefore in relation to a locking device for a wall tie. However it will be appreciated that a locking device such as shown at either end 22, 23 of the rod 21 may be used to secure any elongate element in an opening/bore. For example the device may be used to secure a stud received in an opening in a wall. Such a locking device is also applicable where the structure in which the elongate element is received is soft e.g. made of wood or plastic, as the fingers will dig deep into the surface of the opening to provide efficient grip and resistance against withdrawal rather than a mere shallow digging into the surface and, frictional force where the wall of the opening in which the element is received, is hard, e.g. brick, concrete, metal or the like.

In suitable applications, the fingers of one locking ring may extend relative to the axis of the element at angles different to the fingers or others of the locking rings. For example, the angles may decrease along the element, to provide a graduated force to the inside surface of the opening/bore, as the rod 21 is rotated relative to the female threaded part.

Of course, the fingers at the greater angle to the axis will tend to be urged outwardly prior to the fingers at smaller angles and thus the locking ring having the fingers at the greater angle will become locked in the opening/bore first.

Refering to Fig. 4, a second embodiment of a locking device in accordance with the invention is shown. The locking device for securing an elongate member 110 in an opening 114 in a wall structure 112, comprises in this example, a plurality, in the example three, locking rings 127, 1 28 and 1 29 each substantially identical to locking ring 29 shown in Fig. 2, an abutment 125, comprising a washer W' and bush B', which is secured against axial movement relative to the element 110 in a rearwards direction, by a collar C on the element 110, and in a forwards direction by a separate locking part 160, the locking rings 127, 128, 1 29 being located between the abutment 1 25 and the locking part 160, the locking part 1 60 being outermost of the end 123 of the element 110.

The locking rings are separated from one another by means of cup washers 142 and plain washers 142', the cup washers each serving to prevent the collapse of an adjacent plain end 1 36 of a locking ring, and the plain washers (and the bush B') serving to urge fingers 1 30 of the locking rings 127, 128, 129 outwardly as they are moved towards one another, as hereinafter explained.

The locking part 1 60 has a surrounding flange 1 63 which abuts the plain part 1 36a of locking ring 129, through a cup washer 142", the other end 1 62 of the locking part 1 60 engaging the conical closed end 11 6 of the opening 114 in the wall structure 11 2.

The locking part 1 60 is preferably made of metal, cut and deformed so that parts thereof comprise tangs T which extend inwardly towards the element 110, in a direction away from the abutment 125 and the engagement of the rangs T with the element 110 thus resists movement of the locking part 1 60 away from the abutment.

The locking part 1 60 may alternatively be made of plastics, in which case tangs T may be moulded integrally therewith.

Operation of the locking device will now be described.

The element 110, locking rings 1 27 to 129, abutment 1 25 and locking part 1 60 are inserted into the opening 114 until the end 1 62 of the locking part 1 60 engages the closed end 116 of the opening 114.

The other end 1 22 of the element 110 is then struck with a hammer or other striking tool. This will cause the element 110 to move axially relative to the locking part 116. Because the tangs T extend towards the closed end 11 6 of the opening 114, this movement is not greatly resisted. However the tangs T resist reverse movement of the element 110.

Of course, because abutment 1 25 is fixed relative to the element 110, this movement will urge the flange 1 63 of the locking part 1 60 towards the abutment 1 25 to reduce the separation between the two and the locking rings will be urged towards one another. Their fingers 1 30 will, due to their engagement with the plain washers 142', be urged outwardly into frictional engagement with the inside surface 1 50 of the opening 114, to thus prevent withdrawal of the element 110 and locking member 1 60.

As shown, the elongate element 110 is provided with a circumferential groove G adjacent the end thereof, in which the tangs T can locate when the elongate element 110 has moved a predetermined amount. As shown in Fig. 4, the element 110 has been moved by the hammer blows by this amount so that the tangs T are actually located within the groove G.

As in the Figs. 1 to 3 embodiment, many modifications may be made. As shown only two tangs T are provided in the locking part 1 60 and these are opposite one another. If desired, more than two tanges T may be provided, one or more being provided at spaced longitudinal positions of the locking part 1 60. Preferably though the tangs T are as short as possible so as to provide a maximum resistance to distortion. The tangs need not be provided integrally with the wall of the locking-part 1 60 as shown, but if desired may be provided on a separate element of the locking part, such as a starlock washer secured relative to the remainder of the locking part.

A series of grooves rather than a single groove G may be provided, to achieve a ratchet-like effect as the element 110 moves relative to the locking part 1 60.

Further, the locking rings may be of other configurations such as described above with reference to the first embodiment, and the abutment 1 25 need not be provided by a waher W' and bush B' as described, but could be provided by any other means as required.

As shown, three locking rings are provided which give considerable resistance to withdrawal; where only a lesser resistance to withdrawal is required, less than three locking rings may be provided. For example, only one locking ring may be provided where the elongate element 110 is only subjected to relatively small pull-out loads.

In the Fig. 4 arrangement it will be appreciated that only axial movement of the element 110 is requird to secure the elongate element in the opening 114. This contrasts with the arrangement shown in Figs. 1 to 3 where the elongate element requires both an axial movement to secure the locking member and a rotational movement to cause the separation between the locking part 26 and abutment 25 to reduce.

As described with reference to Figs. 1 to 3, if desired plain washers 142' and cup washers 1 42 may be omitted if these are not required, for example if the locking rings 1 27 to 1 29 are of configurations other than shown, in which case they do not require the additional support of the cup washers or the presence of the plain washers to cause them to expand outwardly.

It will be appreciated that the elongate element 110 shown in Fig. 4 may comprise one end of a remedial wall tie in which case, the arrangement of Fig. 4 may be substituted instead of the arrangement shown at end 23 of the wall tie 10 of the Figs. 1 to 3 embodiment.

However, the elongate element 110 may comprise a stud as shown to which further articles may be secured. The stud may have a threaded end 27 to enable articles to be secured adjacent the wall surface in which the opening 114 is provided.

Referring now to Fig. 5, a third embodiment of the invention is shown. Again, an opening 214 is provided in a wall 212 to receive one end 223 of an elongate element 210 which it is required to secure in the opening 214.

In this embodiment, the end 223 of the elongate element 210 is of reduced diameter and contrasting with the Figs. 1 to 4 embodiments, the remainder of the elongate element 210 is of a diameter only slightly smaller than that of the opening 214.

In this embodiment, a locking part and locking ring are provided as an integral assembly 260. The assembly 260 has a plurality of fingers 230 which extend radially outwardly of the axis of the element 210 and away from the end 223 thereof, the fingers 230 acting in a substantially identical manner to the fingers 30 and 1 30 of the Figs. 1 to 4 embodiments.

The fingers 230, in use, engage the edge 225 of the element 210 which thus provides an abutment, the fingers being urged into a small space S' between the outer surface of the element 210 and the inner surface 250 of the opening 214.

The fingers 230 comprise a splayed end of the member 260, edge 262 of the unsplayed end engaging the conical end surface 216 of the opening 214 and thus preventing further movement of the member 260 inwardly of the opening 214.

It will be appreciated that upon axial movement of the element 210 inwardly of the opening 214, that the abutment provided by the edge 225 of the element will be urged inside the region bounded by the fingers 230 of the assembly 260 to urge them outwardly into tight frictional engagement with the inside surface 250 of the opening 214.

To prevent movement of the element 210 out of the opening, the assembly 260 is again provided with integral tangs T' which extend radially inwardly towards the closed end 216 of the opening 214 away from the abutment 25 and engage a groove in the reduced diameter end 223 of the element 210.

Such an arrangement is suitable where the element 210 is only to be subjected to smaller pull-out loads, as only one set of fingers 230 and tangs T' are provided to resist withdrawal. If required to increase resistance to pull out, a series of assemblies 260 may be received on the end of an elongate element 210 in similar manner to the locking rings of the previous embodiments, but each assembly 260 having tangs T' to prevent withdrawal of the elongate element from the locking ring/ locking part assembly 260.

Again, many modifications may be made.

For example more than the two tangs T' as shown may be provided, and if desired, a separate abutment may be provided instead of the edge 225 of the element 210, in which case the element 210 may be of smaller diameter than that shown, for example substantially the same diameter as the element shown at 110 in Fig. 4.

Claims (29)

1. A locking device for securing an elon gate element in an opening, the device comprising an abutment, a locking part, and at least one locking ring, the locking ring being positioned inwardly of the end of the element between the locking part which is outermost, and the abutment, the locking ring having a plurality of fingers extending radially outwardly of the element towards the other end of the element, and engaging the abutment, the locking part being movable towards the abutment to reduce the separation therebetwen and to cause the fingers of the locking ring to move further outwardly into engagement with the inside surface of the opening, the locking part having means to resist axial movement of the locking part away from the abutment.

2. A device according to Claim 1 wherein the locking part and locking ring are separate.

3. A device according to Claim 1 wherein the locking part and locking ring are provided as an integral assembly.

4. A device according to any one of Claims 1 to 3 wherein the one end of the element is threaded and the abutment comprises a nut screwed thereon to a predetermined position along the element.

5. A device according to Claim 4 wherein the locking part comprises a female threaded part movable towards the abutment upon relative rotation between the female threaded part and the element.

6. A device according to Claim 5 wherein means are provided to facilitate relative rotation between the locking ring and the abutment.

7. A device according to Claim 5 or Claim 6 wherein a locking member is provided to lock the locking part against rotation with the element.

8. A device according to any one of Claims 1 to 4 wherein the locking part comprises a collar substantially surrounding the elongate element, the collar being movable axially of the element towards the abutment to reduce the separation therebetween.

9. A device according to Claim 8 wherein axial movement of the collar along the rod towards said one end is resisted by one or more tangs integral with the collar or provided on a separate element which tangs extend towards the axis of the elongate element and engage the surface thereof.

1 0. A device according to Claim 9 wherein the tangs extend in a direction away from the abutment.

11. A device according to Claim 9 or Claim 10 wherein the elongate element has one or more grooves therein, in which the tangs locate.

1 2. A device according to any one of Claims 1 to 11 wherein the or each of the fingers of the locking ring are made of a material which is malleable so that as the fingers are urged outwardly they become deformed making withdrawal of the element from the opening inreasingly difficult.

1 3. A device according to any one of Claims 1 to 1 2 wherein the fingers comprise a splayed end of the locking ring separated by slits cut axially of the ring, the splayed end decreasing in cross-sectional area along the ring, the outermost edges of the fingers providing abutment portions which engage the inside surface of the opening.

14. A device according to Claim 1 3 wherein the locking device comprise a plurality of such locking rings, each having an end opposite to its splayed end radially seller than the splayed end of the next locking ring nearest the locking part, so that said opposite ends of the rings engage the fingers directly or through one or more intermediate members, to urge the fingers outwardly as the separation between the abutment and the locking part is reduced.

1 5. A device according to Claim 1 3 or Claim 14 wherein the locking part engages said opposite end of the or the nearest locking ring directly or through one or more intermediate members.

1 6. A device according to Claim 1 3 or Claim 14 wherein at least one of the locking rings comprises a locking part integral therewith to resist movement of the locking part and hence locking ring away from the abut ment.

17. A device according to Claim 13 wherein the or each intermediate member between the locking rings, where provided, comprises a washer to ensure that the fingers of the locking ring on which the adjacent washer bears, moves uniformly outwardly to provide efficient grip of the inside surface of the opening.

1 8. A device according to Claim 1 7 wherein the washer is slightly smaller than the inside diameter of the opening so that the fingers of the locking rings do not extend outwardly of the washers until said separation is reduced, when the abutment portions of the fingers are urged into a small space between the washer and the inside surface of the opening to provide strong resistance to with drawal.

1 9. A locking device according to any one of the preceding claims wherein the elongate element comprises a rod of a wall tie, the opening being provided in an inner or outer wall of a cavity wall structure, the rod extend ing through a bore in an outer or inner wall of the structure and through the cavity, into the opening in the inner or outer wall.

20. A locking device according to Claim 1 9 wherein the other end of the rod in the bore in the outer or inner wall is secured relative to the outer or inner wall via one or more further locking rings trapped between a further abutment of the rod and a still further locking part, the further locking ring or rings each having a finger or fingers which extend radially outwardly of the axis of the rod, the fingers being urged outwardly into engagement with an inside surface of the opening as the separation between the further locking part and the abutment is reduced.

21. A locking device substantially as hereinbefore described with reference to and as shown in the Figs. 1 to 3 or Fig. 4 or Fig. 5 of the accompanying drawings.

22. A remedial wall tie having an elongate element comprising a rod, a locking device according to any one of the preceding claims for securing one end of the rod thereof in an opening in the inner or outer wall of a cavity wall structure, and a further locking device according to any one of the preceding claims for securing the opposite end of the rod in a bore in the outer or inner wall structure respectively.

23. A wall tie substantially as hereinbefore described with reference to Figs. 1 to 3 of the accompanying drawings.

24. A method of securing an elongate element within an opening in a structure, using a locking device according to any one of Claims 1 to 21, said method comprising the steps of moving the locking part relatively towards the abutment to reduce the separation therebetween and to cause the fingers of the locking ring to move outwardly into engagement with the inside surface of the opening, the locking part having means to resist axial movement of the locking part away from the abutment.

25. A method according to Claim 24 wherein the elongate element is rotated relative to the locking part to reduce the separation between the abutment and the locking part.

26. A method according to Claim 25 wherein the elongate element is moved axially between the abutment and the locking part.

27. A method according to any one of Claims 24 to 26 wherein the elongate element is a rod of a wall tie according to Claim 22 or Claim 23.

28. A method of securing an elongate element substantially as hereinbefore described with reference to Figs. 1 to 3 or Fig. 4 or Fig. 5 of the accompanying drawings.

29. Any novel feature or novel combination of features disclosed herein and/or shown in the accompanying drawings.