Wire gripping device

A wire gripping device which comprises a body having an internal cavity. There is at least one opening into the cavity whereby a portion of a wire member can be located within the cavity. Inside the cavity there is at least one wire engaging member which is positioned therein by resilient means. The wire engaging member has a wire engaging surface which is located adjacent to but spaced from a fixed surface within the cavity so that a wire member can be moved longitudinally into the cavity in one direction but is prevented from being removed by the engaging member wedging the wire member between the engaging surface and the fixed surface.

This invention relates to a wire gripping device. 
There are many applications for a device which may be used to grip a length 
of wire. For example in wire fence lines it is often necessary to be able 
to join the ends of two lengths of wire. One method of connecting the ends 
is by twisting or crimping them together. This method is widely used and 
whilst it is effective it does involve time and in the case of crimping 
can involve specialised tools. In addition, and more particularly with the 
twisting together of the wire ends, unwanted stresses can be set up in the 
wire once it had been strained with resultant failure of the join. 
Further, the join once formed is difficult to release. 
In other applications such as in vineyards it is often necessary to be able 
to grip the end of a wire so that the said end can be anchored. Once again 
the fastening can be carried out by the wire end being passed through a 
locating point and then twisted or crimped back upon itself. The problems 
which are mentioned above can once more arise. 
The object of the present invention is thus to provide a wire gripping 
device having such a construction that a length of wire can be quickly and 
conveniently engaged and firmly retained in the device. 
A further object of the invention is to provide a wire gripping device 
whereby the wire can be released from the device if required. 
In its broadest aspect the invention provides a wire gripping device 
comprising a body, an internal cavity with inset body, an opening into 
said cavity whereby a portion of a wire member can locate within said 
cavity, at least one wire engaging member located within said cavity, 
resilient means which position said wire engaging member within the cavity 
such that a wire engaging surface of the wire engaging member is located 
adjacent to, but spaced from, a fixed surface so that a wire member can be 
moved longitudinally into said cavity in one direction but is prevented 
from being removed by said wire engaging member wedging the wire member 
between the wire engaging surface and said fixed surface. 
In its preferred form the device has a plurality of wire engaging members 
which is suspended in the cavity with the members being spaced apart from 
each other and the fixed surface by the resilient means. The wire engaging 
members can be of flat elongate shape and are located in a parallel spaced 
apart array by a resilient spacer member located between and coupling each 
pair of adjacent engaging members, the engaging member at each end of the 
array being coupled to a wall surface of the cavity by a resilient spacer 
member. In this form the wire engaging surface is formed by the edge of 
one short side of the elongate wire engaging member. The wire engaging 
surface can be provided with a gripping surface such as for example one or 
more longitudinal ridges. The wire engaging surface can also be formed as 
a curved recess. 
In a further form of the invention the body can include two cavities 
located side by side with each of the cavities however being a spacial 
array of the wire engaging members. Alternatively each of the wire 
engaging members can have a pair of wire engaging surfaces which locate 
opposite a fixed surface. 
The resilient spacer members can be formed of a suitable rubber or plastics 
material. In a preferred form each resilient spacer member is of disc 
shape and is adhered to a face surface of the elongate member.

The body 10 of the device is essentially tubular and referring to the first 
form of the invention preferably has a shape which is more clearly 
illustrated in FIGS. 2 and 4. The body can be of any suitable construction 
such as being fabricated from sheet steel or formed as an extrusion. The 
diameter of the lower wire receiving portion of body 10 is such as to 
accommodate the diameter of the wire which is to be gripped by the device. 
The body 10 has end walls 11 which are fastened to body 10 in any 
convenient manner for example by crimping therein. 
Situated between the end walls 11 are a plurality of wire engaging members 
12 which are elongate and have a shape which is complementary to the 
internal shape of the cavity 14 within body 10. The wire engaging ends of 
members 12 have wire engaging surfaces which are formed by a curved recess 
15 which is of a radius similar to that of the wire W. Members 12 are 
basically situated parallel to one another and are spaced apart by 
resilient spacer members 16. These spacer members 16 are of a suitable 
resilient material such as natural or synthetic rubber, foamed natural or 
synthetic rubber, resilient plastics material or foamed resilient plastics 
material. A spacer 16 is situated between the end walls 11 and the 
adjacent wire engaging members 12. 
In use a wire is inserted through opening 17 in one end wall 11 and pushed 
through cavity 14 so as to project from the opening 17 in the other end 
wall 11. In the arrangement shown in FIG. 1 the movement of the wire W is 
shown by arrow A. During this movement the wire engaging members 12 
incline away from the advancing wire so that free passage of the wire 
between recesses 15 and curved wall surface of cavity 14 is permitted. If, 
however, the wire is pulled in the direction of arrow B the wire engaging 
members 12 become wedged between wire W and the upper wall surface of 
cavity 14 so gripping the wire W between recesses 15 and lower curved wall 
surface of cavity 14. The wire W is thus firmly gripped by the device 
meaning that substantial force can be applied in the direction of arrow B 
without the wire W slipping through body 10. 
Body 10 can be provided with means (not shown) whereby the body can be 
clamped to a fixture such as for example a post. Accordingly the body 10 
can be placed in position and a wire W inserted therein and strained in 
the direction of arrow A until the required strain has been achieved. 
Release of the pulling force on wire W would mean that normally it would 
move in a direction of arrow B but this is prevented by the clamping force 
set up between wire engaging members 12 and the wall surface of cavity 14. 
When two wires are to be joined together an arrangement such as illustrated 
in FIG. 5 can be employed. In this arrangement the body 10 is formed with 
two cavities 14 and as can be seen from FIG. 5 the resultant device is 
basically a pair of the devices as shown in FIGS. 1 to 4 but coupled side 
by side. 
A further form of the invention is shown in FIGS. 6 to 8 where in a pair of 
wires can be joined together. The device is constructed in the same manner 
as previously disclosed except that the wire engagement members have a 
circular recess 15 formed at each end thereof. Once again the wire 
engaging members are so shaped that they may slide within cavity 14 but 
are not permitted to rotate therein. 
Referring to FIG. 9 of the drawings yet a further form of the invention is 
shown. In this form wire engaging members 12 have a flat wire engaging 
surface 15' rather than the recess 15 of the previously disclosed forms. 
As shown in FIG. 10 the wire engaging surface 15' is so formed as to 
provide a serrated or other gripping surface. As shown the preferred form 
is provided by a number of parallel longitudinal sharp ridges 17. 
Wires W are inserted into opposite ends of body 10 in a manner shown in 
FIG. 6. During movement in the directions indicated by arrows A the wires 
are free to move through the body due to the inclined positions taken up 
by the wire engaging members 12. When a pulling force is applied to one or 
other of the wires in the direction of arrow B the wire engaging members 
tend to incline in the opposite direction and thus wedge the two wires W 
between the respective circular recesses 15, or in the form of FIGS. 9 and 
10 the flat surface 15', and curved wall surfaces of the cavity 14. The 
two wires can thus be strained to the required amount of strain and then 
released whereby they will be wedgedly retained within body 10. 
It will be appreciated that the wire(s) W can be inserted into body 10 in 
either direction as the spacer members 16 will allow the wire engaging 
members 12 to tilt away in the direction of movement of the wire and so 
permit the wire to freely move through the body. Reverse movement of the 
wire will result in the wedging action set up by wire engaging members 12 
to take place. Once a wire is engaged within the body it will be retained 
in position until the wire is once more pulled in the direction of arrow 
A. The device can thus be removed from a wire by pulling the wire in the 
direction of arrow A until it becomes clear of the body. 
The invention thus provides a device which can be quickly and conveniently 
placed on a wire and will automatically grip the wire when said wire is 
pulled in a direction which is the reverse of which the wire was inserted 
into the body. The device can provide a means of anchoring a wire to a 
fixture or else for joining the ends of two wires.