GB2149370A

GB2149370A - Anchor

Info

Publication number: GB2149370A
Application number: GB08329913A
Authority: GB
Inventors: Colin Ian Campbell; Roger Frederick Allen
Original assignee: Camal Ltd
Current assignee: Camal Ltd
Priority date: 1983-11-09
Filing date: 1983-11-09
Publication date: 1985-06-12
Also published as: GB8329913D0

Abstract

An anchor adapted to be fired from a gun, such as an air launchter 20, into the ground to secure a line 13, the anchor having a plurality of flukes 2 hinged to a pointed head 1 which eases penetration of the anchor into the ground. The flukes are initially retained by a ring 22 in a position one parallel to another inside the gun, the ring disintegrating on firing so that when the anchor penetrates the ground, the line can be tensioned pulling the anchor backwards causing the flukes to open out and dig into the ground holding the anchor and thereby the line fast. <IMAGE>

Description

SPECIFICATION Anchor The present invention relates to an anchor.

Traditional anchors are used by boats and ships. They comprise flukes for embedding in the seabed and a stem to which the flukes are secured and via which a line to the ship is secured to the flukes. Various known anchors have their flukes pivotably secured to the stem whereby the flukes may embed whichever way up the anchor lies on the seabed.

One such pivoted fluke anchor has its flukes so pivotably attached to the stem that they lie along the stem when it is not in use.

The anchor of the present invention has been invented for use on land-as well as on the seabed-where it is intended to force the anchor into the ground rather than rely on its weight to embed it.

An anchor for this purpose exists. It comprises a single fluke having an integral head arranged to point in the opposite direction from the point of the fluke. This anchor is intended to be driven into the ground with a rod engaging the anchor to drive its head forwards. A line is attached to the anchor intermediate its head and its fluke. When the rod is withdrawn and the anchor is pulled back by the line, its fluke digs into the side of the bore in the ground caused by its insertion.

This digging-in action turns the anchor until it lies transverse the bore whereupon it is fast in the ground, at least against its rated load for the particular soil of the ground.

The anchor of the present invention is intended to be "fired" into the ground by a gun. The single fluke anchor mentioned above is not symmetrical and relies on its driving rod to be guided straight into the ground. Hence it is not suitable for "firing" into the ground.

Conventional marine anchors, even those having their flukes stowed along their stems are not suitable for "firing" into the ground due to their heavy construction (they rely on their weight for embedding). Too heavy an anchor requires too heavy a gun.

The object of the present invention is to provide an anchor suited to being "fired" into the ground by a gun which may be a pyrotechnic gun or an air launcher-i.e. a gun using compressed gas as a propellant.

According to a first aspect of the invention, there is provided a spreadable anchor comprising at least one fluke and an anchor line, for firing from a gun the anchor being packable within a circular cylindrical space with the anchor line emerging from the rear end of the packed anchor and passing along the outside of the anchor but still within the circular cylindrical space whereby, when the anchor is loaded into the gun, the line passes out of the muzzle of the gun, the anchor further comprising means for frictionally retaning the packed anchor in the gun when the gun is angled down for firing of the anchor into the ground.

According to a second aspect of the invention there is provided a spreadable anchor comprising a head shaped to penetrate the ground, at least two flukes attached to the head and adapted to hinge symmetrically away from each other, and line attachment points provided on the head and/or on the flukes for a line to be held by the anchor, the arrangement being such that on "firing" of the anchor into the ground, the flukes dig in and spread symmetrically when the line is tensioned.

To allow the line to pass the anchor when packed and loaded into the gun, the head preferably has a groove or a flat. However the head is also preferably part-circular for centring the anchor in the barrel of the gun.

Although it is envisaged that the line may be attached solely to the head or solely to the flukes, it is preferred that it is attached to both the head and the flukes. Where the line is attached solely to the head, separate means is required for restraining the flukes from spreading past a point at which they cease to co-operate to hold the anchor, because they are angled back to form a Vee pointing towards the line. This restraining function is performed by attachment of the line to the flukes along via a division in the line where such attachment is provided.

Whilst it is envisaged that the flukes may be weakened to bend adjacent the head for hingeing away from each other, it is preferred that they be pivotably connected to the head.

To assist initial spreading of the flukes they may diverge slightly at their free ends remote from the head. Such shaping can help in transferring load from an obturating ring in the gun to the anchor on firing and can also help in retaining an initial antispreading ring which is preferably provided. The antispreading ring may be of plastics material and sized to retain the anchor in the gun prior to firing.

The antispreading ring preferably performs the function of frictionally retaining the anchor in the gun prior to firing.

According to another aspect of the invention there is provided a method of anchoring a line to the ground, consisting in firing from a gun into the ground an anchor adapted to spread on movement backwards in the ground and equipped with an anchor line, and after firing drawing the anchor backwards with its lines thereby spreading it until it is fast in the ground.

To help understanding of the invention a specific embodiment thereof will now be described with reference to the accompanying drawings in which: Figure 1 is a side view of an anchor of the invention ready for loading into a gun, Figure 2 is a front view of the anchor of Fig. 1, Figure 3 is a front end view of the anchor, Figure 4 is a side view of the anchor when spread, Figure 5 is a cross-sectional view of a gun loaded with the anchor prior to firing, and Figure 6 is a diagrammatic view of the anchor when spread in the ground after firing.

The anchor shown in the drawings comprises a head 1 and two flukes 2 pivotally attached to the head 1 at part-circular crosssection, transverse grooves 3 in the head in which ribs 4 on the forward ends of the flukes engage. The ribs 4 may be of round bar welded to the flukes or may be formed as turned over heads of the forward ends of the flukes. The left-hand rib 4 in Fig. 1 is shown as being of the former construction, whilst the right-hand rib is of the latter construction. The flukes are generally flat and have turned in flanges 6 running forwards along their side edges from the free ends 7 of the flukes. The flanges 6 do not extend completely to the forward ends of the flukes to permit clearance at the rear part 8 of the head having the grooves 3. The ends of the grooves are closed by pins 9 to retain the ribs 4 therein.

The forward end 10 of the head is pointed for easing penetration into the ground. An intermediate portion of the head is of circular cross-section save for flats 11 in alignment with the generally flat flukes, see Fig. 3. At the rearward end of the anchor, the flats of the flukes spread slightly at 12.

Fig. 4 shows the anchor when spread as in the ground. A line 1 3 divides at eye 14 into two fluke lines 15 and a head line 16. The flukes are provided close to their free ends 7 with welded on eyes 1 7 for the fluke lines 1 5 and the head is provided at its rear part 8 with a welded on eye 18 for the head line.

The lines are of such length as to restrain the flukes from spreading beyond a required angle when the head line 1 6 as well as the fluke lines 1 5 are taut.

Fig. 5 shows the anchor loaded into the barrel 19 of a gun 20 having propellant gas providing means 21. The head 1 of the anchor centres itself in the barrel by its part circular cross-section. The rear end of the anchor is centred by an antispreading ring 22 of plastics material which has been fitted onto the anchor from its forward end until it rests against the spreadings 12. The antispreading ring 22 is a tight fit in the barrel 1 9, to retain the anchor in the barrel when pointed down for firing, and a tighter fit on the flukes to maintain itself in position against the spreadings during loading of the anchor into the barrel 1 9. The line 1 3 passes out of the rear of the anchor via a slot 23 in one of the flukes and a groove 24 in the antispreading ring 22 and lies along the anchor prior to firing.An obturating disc 25 is provided behind the anchor.

On firing the anchor penetrates the ground to a certain depth according to the nature of the ground and the propellant charge. During penetration the antispreading ring 22 disintegrates. When the line 1 3 is tensioned, the spreadings 1 2 dig into the ground at the edge of the bore formed by the anchor on firing and cause the anchor flukes to spread to their Figs. 4 and 6 position. Tensile load in the line 1 3 is spread to the head 1 and the rear end of the flukes via the lines 16, 1 5 and reacted as compression in the ground in "front" of the flukes. Should the angle of the line 1 3 change, the anchor will shift in the ground to align with the line.

The invention is not intended to be restricted to the details of the above described anchor. For instance three or more flukes may be provided. The lines may be secured to the flukes at fingers stamped out from the flukes.

The flanges 6 may extend to the very forward end of the flukes to abut the rear part 8 of the heat, thus obviating the need for the pins 9.

The grooves 3 may be bores to accommodate pins extending between the forward ends of the flanges for pivoting of the flukes. In certain ground it may be necessary to provide a spring to initially spread the flukes.

It is envisaged that the head will usually be a forging. The material of the anchor will vary according to its use. Light-weight anchors may be of aluminium alloy. Medium duty anchors may be of galvanised steel. Long service anchors may be of stainless steel.

Claims

1. An anchor comprising a head shaped to penetrate the ground, at least two flukes attached to the head and adapted to hinge away from each other, and line attachment points on the head and/or flukes for an anchor line, the arrangement being such that on insertion of the anchor into the ground, the flukes dig in and spread outwardly when the anchor line is tensioned.

2. An anchor as claimed in claim 1, wherein the anchor is packable within a circular cylindrical space and adapted and arranged when so packed for loading into a gun that the anchor line can be attached to the attachment points, emerge from the rear end of the packed anchor and pass along the outside of the anchor within the circular cylindrical space for passing out of the muzzle of the gun when the anchor is loaded therein.

3. An anchor as claimed in claim 2, further comprising means for frictionally retaining the packed anchor in a gun when the gun is angled down for firing of the anchor into the ground.

4. An anchor as claimed in claim 3, wherein the retaining means is a retaining ring for holding the flukes together prior to insertion of the anchor in the ground, the retaining ring disintegrating on or before the anchor penetrates the ground.

5. An anchor as claimed in claim 2, wherein the head includes a front conical section to ease penetration of the anchor in to the ground and a rear section adapted for pivotal connection of the flukes thereto.

6. An anchor as claimed in claim 5, wherein each fluke has at its forward end a rib transverse to its longitudinal axis and the rear section of the head includes a plurality of grooves in each one of which a respective one of the ribs are free to rotate.

7. An anchor as claimed in claim 6, wherein each rib is formed by turning over the forward end of its fluke.

8. An anchor as claimed in claim 6, wherein each rib is a length of round bar welded to the forward end of its fluke.

9. An anchor as claimed in any preceding claim wherein each fluke is generally flat and has edge flanges along at least the major portion of its length.

10. An anchor as claimed in claim 9, as appendant to claim 6, wherein the flanges of each fluke terminate short of the rib and pins are provided in the head for retaining the rib in its groove.

11. An anchor as claimed in claim 4 or any one of claims 5 to 10 as appendant to claim 4, wherein a projection is provided on each fluke at its rear end against which the retaining ring abuts when encircling the flukes for holding them together prior to insertion of the anchor in the ground.

1 2. An anchor as claimed in any preceding claim, wherein said attachment points comprise an eye on each fluke near its rear end; the anchor including an anchor line comprising fluke lines, each attached to its eye and the end of the main line, the length of the fluke line being such as to allow the flukes to open out to a predetermined angle.

1 3. An anchor as claimed in claim 1 2, wherein a further attachment point is provided as an eye on the head and a head line is attached to this eye and the end of the main line.

14. The combination of an anchor and a gun, the anchor as claimed in claim 4 or any one of claims 5 to 1 3 as appendant to claim 4, the gun having a barrel into which the anchor is inserted for firing, the retaining ring being dimensioned to be a snug fit in the barrel to thereby retain the anchor therein prior to firing.

1 5. The combination of an anchor and a gun, the anchor being as claimed in claim 2 or any claim appendant thereto and the gun having a barrel into which the anchor is inserted for firing, the anchor including an anchor line attached thereto and passing from the rear end thereof, outside of the anchor and inside the barrel to emerge from the muzzle of the gun.

1 6. The combination of claim 14 and claim 1 5 wherein the retaining ring and the head of the anchor are cut away to allow passage of the anchor line.

1 7. A method of anchoring a line to the ground comprising firing from a gun into the ground an anchor having the line attached thereto and flukes which are adapted to spread from an unspread position when in the gun, and then pulling the line and anchor in a direction opposite to that in which it was fired into the ground to spread the flukes outwards to dig into the ground and thereby retain the anchor fast in the ground.

18. An anchor substantially as hereinbefore described with reference to the accompanying drawings.