GB2106609A

GB2106609A - Wedge

Info

Publication number: GB2106609A
Application number: GB08224444A
Authority: GB
Inventors: Dennis Morgan Emmett O'donovan
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-08-25
Filing date: 1982-08-25
Publication date: 1983-04-13

Abstract

A wedge 13 comprising a body 12 that tapers generally from a driving end to a thin end and having a pair of major wedging faces, each extending between the driving end and the thin end, defining an acute angle therebetween, at least one of which major wedging faces is provided with a plurality of ridges 14, 15 extending substantially parallel to at least one of the said ends of the wedge. <IMAGE>

Description

SPECIFICATION Wedge This invention relates to wedges.

According to the present invention there is provided a wedge comprising a body that tapers generally from a driving end to a thin end and having a pair of major wedging faces, each extending between the driving end and the thin end, defining an acute angle therebetween, at least one of which major wedging faces is provided with a plurality of ridges extending substantially parallel to at least one of the said ends of the wedge.

The ridges are desirably formed of a hard material, for example wood, metal or a plastics material. Preferably the ridges are made of a hard resilient plastics material even more preferably a plastics material having a high izod number. The whole body may be made of such a material or, alternatively, the body comprises a main wedge-shaped part of a rigid hard material such as wood and a surface portion made of hard resilient material fastened to at least one of the major faces of the main wedge-shaped part and having the ridges formed thereon.

The surface portion may comprise a plurality of abutted strips, each having the ridges extending lengthwise thereof. Such strips may have edges adapted to interengage with a corresponding edge of anotherstrip.

The ridges may extend over a part only of the said one major wedging face or may extend over substantially the whole of the said one major wedging face.

In use the wedge of the invention may be used as a single wedge in place of conventional wedges with substantially plantar major wedging surfaces. For certain applications, as for example, in supporting railway tracks, particularly in underground railway tunnels, during re-concreting of the sleepers, the wedges of the invention may be used in pairs to support a corresponding rail. In this case a first wedge is typically held in position underthe rail with its ridged wedging face uppermost and then the other wedge is inserted under the rail over the first wedge, with its ridged surface downwards and with the ridges thereon parallel to the ridges of the first wedge, and driven home so that its thin end is driven towards the driving end of the first wedge.During the wedge driving operation the ridges can slide one over another but, in the wedged position, the ridges on the two wedges interengage with one another and lock the wedges, thus preventing their with drawal in the wedging direction under normal circumstances. However it is readily possible to disengage the wedges one from another by means of a sideways blow delivered transverse to the wedge-driving direction or to dislodge the wedges as a pair by means of a sharp blow on one of their driving ends, e.g. the driving end of the lower wedge.

In a preferred embodiment the wedge may be provided with keying means extending in the wedging direction along the ridged weding surface for engagement with a complementary formation on a mating wedge to hinder relative movement between the two wedges transverse to the wedging direction in use thereof. Such a keying means may comprise a ridge or groove extending transverse to the ridges for engagement with a corresponding groove or ridge respectively on the mating wedge. With such a construction the wedges should be disengaged as a pair as described above.

The invention further provides a wedging device comprising a plurality of wedge portions fast one with another each of which wedge portions compris- es a body portion that tapers generally from a thick end to a thin end and has a pair of major wedging faces, each extending between the thick end and the thin end, defining an acute angle therebetween, at least one of which major wedging faces is provided with a plurality of ridges extending substantially parallel to at least one of the said ends of the respective wedge portions, and the wedging direction of each wedge portion being arranged to be substantially opposite to the wedging direction of at least one other of the wedge portions.In such a device the other major wedging face of each wedge portion is preferably planar and is co-planar with the corresponding wedging face of the other wedge portion or portions. In a particularly preferred form there are three wedge portions.

The wedging device of the invention is intended for use in conjunction with one or more wedges according to the invention. To support an article, such as a railway track or a pit prop, the wedging device is placed underneath and a wedge according to the invention is driven home into wedging relationship with each of the corresponding wedge portions, the or a ridged surface of each wedge liying in contact with and engaging the or a corresponding ridged surface of each wedge portion.

In order that the invention may be clearly under- stood and readily carried into effect some preferred embodiments thereof will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, wherein: Figure 1 is a side view of a wedge constructed in accordance with the invention; Figure 2 is an enlarged view through a hard resilient plastics extrusion suitable for use in the construction of the wedge of Figure 1; Figure 3 is a side view of another form of wedge constructed in accordance with the invention; Figure 4 is an end view of the wedge of Figure 3 in the direction of the arrow A of Figure 3; Figure 5 is a side view of a wedging device according to the invention;; Figure 6 is an end view, in the direction of the arrow B of Figure 5, of the device of Figure 5; Figure 7 is a side view of a further form of wedge accordingtotheinvention; Figure 8 is an end view of the wedge of Figure 7 in the direction of the arrow C of Figure 7; and Figure 9 is a similar end view of a modified form of wedge designed to engage with the wedge of Figures 7 and 8.

Referring to Figure 1 of the drawings a wedge 1 has a main body part 2 of wood and a surface portion 3 of hard resilient plastics material fastened, e.g. by gluing, by nailing, or by means of screws, or in any other convenient manner, to one of the major surfaces of main body part 2. Main body part 2 tapers generally from a driving end 4 to a thin end 5.

Surface portion has a plurality of surface ridges 6 formed thereon, each separated by a trough 7 from its neighbour. These ridges 6 run substantially parallel to at least one, and preferably to both, of the driving and thin ends 4 and 5. As can be seen from Figure 1, the ridges 6 and troughs 7 together form a sinusoidal pattern about the plane 8 of the respective major wedging face of the wedge 1. This plane 8 defines, together with the other major wedging face 9, which is planar, an acute angle at, or beyond, the thin edge 5 of the wedge 1.

In Figure 1 the height of the ridges 6 is greatly exaggerated. In practice the height of the ridges 6 above the troughs 7 will usually be much smaller e.g. about one sixteenth inch (about 1.6 mm).

Figure 2 shows a strip-like extrusion 8 having a flat face 9. Typically the total height of the ridges 6 above the flat face 9 is about three sixteenths inch (about 4.8 mm), whilst the height of the troughs 7 above flat face 9 is about one eighth inch (about 3.2 mm). In a particularly preferred form extrusion 8 is about 4 inches (about 101.6 mm) wide and of indefinite length. Along one edge extrusion 8 has a generally V-shaped notch 10 whilst its other edge has a V-shaped protrusion 11 which is adapted to fit in a notch 10 of an identical piece of the same extrusion. In this way the surface of a wedge can be covered by a plurality of side-by-side interlocking strips to form the surface portion 3 of the wedge of Figure 1.

In use a pair of wedges 1 can be used to support the rails during re-concreting of the sleepers of an underground railway. To this end one wedge is driven in from either side of the rail, one with its surface portion 3 uppermost and the other with it undermost so that the surface portions 3 slide one over another. Afterthe wedges 1 have been driven home the ridges co-operate to prevent movement of the wedges in the wedging direction. It is, however, a simple matter to dislodge the wedges with a sideways blow in a direction transverse to the wedging direction, or to dislodge the wedges as a pair by means of a sharp blow on one of their driving ends 4, so that the wedges can be removed, after the concrete has set, for re-use. In some circumstances it may be beneficial to coat the wedges with a heavy grease prior to use.Not only does the grease help to lubricate the wedges during the driving operation but also it helps to prevent separation of the wedging surfaces due to vibration of the rail.

Figures 3 and 4 illustrate a further form of wedge 12. On one of its major wedging faces 13 it has a plurality of ridges 14 and troughs 15 forming together a generally sinusoidal wave pattern. Such a wedge is similar to wedge 1 of Figures 1 and 2 but is moulded in one piece from a plastics material having a high izod value.

Figures 5 and 6 illustrate a wedging device 21 according to the invention. This consists of a one piece moulding or casting having three wedge portions 22, 23, 24 arranged side-by-side so that the wedging direction of wedge portion 23 is opposite to the wedging direction of wedge portions 22 and 24.

As can be seen from Figure 5, each of the wedge portions 22 to 24 has a common major wedging face 25 whilst the other major wedging face of each wedge portion 22, 23 and 24 is provided with a sinusoidal pattern of ridges 26 and troughs 27 extending parallel to the ends of the respective wedge portion.

In use the wedging device 21 is used in conjunction with three wedges of the type illustrated in Figure 1 or in Figures 3 and 4. After placing the device in position under the article to be supported, e.g. a railway line or a pit prop, the wedges are driven home in turn. In each case the ridged wedging surface of the wedge is positioned to contact and engage with the corresponding ridged surface of one of the wedge portions 22 to 24. In each case the thin end of the wedge is driven towards the thick end of each wedge portion. As two of the wedges are driven home in the opposite direction to the third wedge, the combination is held in place securely and supports the article securely.

Wedge 31 of Figures 7 and 8 has a driving end 32 and a thin end 33. It has a planarface 34 and a ridged wedging face formed with ridges 35 and valleys 36 extending parallel to the ends 32 and 33. Extending at right angles to and between the ends 32 and 33 is a key portion 37; this is designed to engage in a corresponding keyway 38 provided in wedge 41 of Figure 9 so as to prevent movement of the wedges 31 and 41 relative to one another, after they have been driven home, in a direction transverse to the driving direction.

In the illustrated embodiments the ridges and troughs form an essentially sinusoidal wave pattern.

It is, however, possible to use ridges of other shapes, for example, ridges of saw-tooth form in conjunction with arcuate section troughs or with V-section troughs. Similarly one can combine round-topped ridges with V-section troughs.

In the illustrated embodiments the major wedging faces extend over the whole distance between the driving end and the thin end. It is equally possible to have other forms of wedge in which there are, for example, bevel surfaces adjacent one or both of the ends and between that end and the corresponding major wedging face.

Claims

1. A wedge comprising a body that tapers generally from a driving end to a thin end and having a pair of major wedging faces, each extending between the driving end and the thin end, defining an acute angle therebetween, at least one of which major wedging faces is provided with a plurality of ridges extending substantially parallel to at least one of the said ends of the wedge.

2. A wedge according to claim 1, in which the ridges are formed of a hard resilient material.

3. A wedge according to claim 1 or claim 2, in which the body comprises a main wedge-shaped part and a surface portion made of hard resilient material fastened to at least one of the major faces of the main wedge-shaped part and having the ridges formed thereon.

4. A wedge according to claim 3, in which the surface portion comprises a plurality of abutted strips, each having the ridges extending lengthwise thereof.

5. A wedge according to claim 4, in which the strips have edges adapted to interengage with a corresponding edge of another strip.

6. A wedge according to any one of claims 1 to 5, in which the ridges form part of a sinusoidal wave pattern.

7. A wedge according to any one of claims 1 to 6, in which keying means are provided extending in the wedging direction along the ridged wedging surface for engagement with a complementary formation on a mating wedge to hinder movement between the two wedges transverse to the wedging direction in use thereof.

8. Awedge according to claim 1 constructed substantially as herein described with particular reference to Figures 1 and 2 of the accompanying drawings.

9. Awedge according to claim 1 constructed substantially as herein described with particular reference to Figures 3 and 4 of the accompanying drawings.

10. Awedge according to claim 1 constructed substantially as herein described with particular reference to Figures 7 and 8 or 9 of the accompanying drawings.

11. A wedging device comprising a plurality of wedge portions fast one with another, each of which wedge portions comprises a body portion that tapers generally from a thick end to a thin end and has a pair of major wedging faces, each extending between the thick end and the thin end, defining an acute angle therebetween, at least one of which major wedging faces is provided with a plurality of ridges extending substantially parallel to at least one of the said ends of the respective wedge portion, and the wedging direction of each wedge portion being arranged to be substantially opposite to the wedging direction of at least one other of the wedge portions.

12. A wedging device according to claim 11, in which the other major wedging face of each wedge portion is planar.

13. Awedging device according to claim 12, in which the other major wedging faces of the wedge portions are co-planar one with another.

14. Awedging device according to claim 11 constructed and arranged substantially as herein described with particular reference to Figures 5 and 6 of the accompanying drawings.

15. Support means comprising, in combination, a wedging device according to any one of claims 11 to 14 and at least one wedge according to any one of claims 1 to 10.