WO2005090716A1

WO2005090716A1 - Apparatus for recovering barrier

Info

Publication number: WO2005090716A1
Application number: PCT/ZA2005/000052
Authority: WO
Inventors: Richard Bruce Cochrane
Original assignee: Richard Bruce Cochrane
Priority date: 2004-03-19
Filing date: 2005-03-16
Publication date: 2005-09-29
Also published as: ZA200608423B

Abstract

Apparatus (10) for recovering an extended length of coiled barbed tape which includes an endless conveyor (80, 82) chain which has a number of spring loaded catches (90) which engage with the coils and draw the coils onto a beam. The catches (90) deflect resiliently if subjected to excessive loading forces.

Description

APPARATUS FOR RECOVERING A BARRIER

BACKGROUND OF THE INVENTION

[0001] This invention relates to apparatus for recovering a barrier such as an elongate, extended, flexible coil barrier of barb tape, barb wire or a similar material.

[0002] South African patent No. 98/10149 describes a mobile barrier module which makes use of coils of deterrent material which can rapidly be deployed onto the ground. The barrier is recovered by using a mechanism which feeds the coils, in a compressed configuration, onto a collecting beam. The collector mechanism makes use of a chain conveyor with a plurality of hooks which are engageable with coils of the deterrent material. The conveyor is driven by means of a dc motor which operates through a clutch and a reduction gearbox.

[0003] It has been found that the collector mechanism is at times largely ineffectual. The hooks on the chain conveyor do not always readily disengage from the coils of the deterrent material with the result that portions of the deterrent material are held captive by the hooks and are drawn along with the chain conveyor. The deterrent material can then become entangled with the conveyor causing the drive motor to stall or burn out, or causing one or more gears in the gearbox to be stripped.

SUMMARY OF INVENTION

[0004] The present invention is concerned with recovery apparatus which at least partly alleviates the aforementioned problem. [0005] The invention provides apparatus for recovering an elongate, extended, flexible, coil barrier which includes a beam, and a conveyor which includes at least one support which is positioned adjacent at least a portion of the beam, a plurality of catch members which are pivotally attached at spaced intervals to the support, a plurality of biasing devices which are respectively associated with the catch members, with each biasing device being mounted to bias a respective catch member in a first direction relatively to the support, and a drive mechanism for driving the support whereby the catch members are successively engageable with respective sections of the barrier thereby to draw the sections in succession onto the beam and wherein each catch member is pivotally deflectable relatively to the support in a second direction opposite to the first direction against the biasing action of the respective biasing device if force which is exerted on the catch member, as a result of its engagement with the barrier, exceeds a force exerted on the catch member by the respective biasing device.

[0006] The support may take on any suitable form and may be one of a plurality of similar supports. Preferably though each support is an endless flexible element eg. an endless chain or cable.

[0007] In a preferred embodiment use is made of two elongate lengths of chain which are closed loops and which are positioned on respective opposed sides of the beam substantially parallel to each other. The chains are driven in unison by the drive mechanism. Each chain includes a plurality of the catch members.

[0008] In a horizontal sense each catch member has an extremity which is moved to a point which is higher than an adjacent uppermost surface of the beam as the support (endless chain) is driven by the drive mechanism. [0009] The support may be mounted for limited pivotal movement about a horizontal axis. This enables the inclination of the support to be varied which means that the angle at which each endless chain is moved, is also varied.

[0010] The beam may be positioned at one end of an elongate support on which the recovered barrier is stored.

[0011] The apparatus of the invention may be mounted on a load bed of a vehicle. A smooth guide may be positioned adjacent the conveyor, at least at a location which is near a free end of the beam, with the catch members being positioned between the beam and the smooth guide.

[0012] The apparatus may be near an extremity of the beam or at an intermediate position on the beam. A first apparatus and a second apparatus may be positioned at selected locations on the beam.

[0013] In one arrangement the apparatus is mounted to a device which may be in the nature of a fork lifter so that the apparatus is at least vertically movable and, preferably, horizontally movable.

[0014] The invention also extends to a method of recovering an elongate coiled barrier which includes the steps of directing a guide into coils at one end of the barrier, engaging catch members on a conveyor with uppermost sections of the coils, actuating the conveyor to draw the barrier onto a support thereby to compress the coils on the support, and allowing a catch member to deflect, to disengage from a respective coil section, if a force exerted on the catch member by the coil section exceeds a predetermined biasing force. BRIEF DESCRIPTION OF THE^{^}DRAWINGS

[0015] The invention is further described by way of examples with reference to the accompanying drawings in which:

Figure 1 is a side view of apparatus according to the invention in different modes of operation;

Figure 2 has two views namely an end view of the apparatus of Figure 1 installed on a vehicle, and an enlarged end view of the apparatus;

Figure 3 has two enlarged views of a portion of a conveyor used in the apparatus of the invention illustrating the mounting arrangement of a catch member which is used in the conveyor;

Figure 4 is a side view, on a reduced scale, showing the recovery apparatus on a vehicle which is used for deploying and then recovering a barrier;

Figure 5 shows a different installation position of the apparatus;

Figure 6 shows the apparatus on a fork lifter; and Figure 7 illustrates the use of the fork lifter.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0016] Figures 1 to 4 of the accompanying drawings illustrate apparatus 10 according to the invention mounted on a load bed 12 of a deploying and recovery vehicle 14.

[0017] The load bed includes an elongate support or beam 16 which extends over the load bed. A plurality of coils of barb tape 18 are normally supported on the beam 16 in a compressed state for storage and transport purposes. In this example the barb tape is arranged in first and second underlying coils 20 and 22 and an uppermost coil 24, see Figure 2 which shows the coils in cross section. The coils, when compressed, are supported on the beam which extends through the uppermost coil 24. This aspect is known in the art and for this reason is not further described herein.

[0018] The compressed coils are readily deployed on ground simply by moving the coils along the beam 16 so that free ends thereof rest on the ground. The vehicle is then slowly driven forward and the compressed coils are paid out from the beam taking up an extended configuration on the ground to form a barrier.

[0019] When the barrier is to be recovered it is necessary to draw the barrier onto the beam and to compress the various coils. This aspect has presented considerable difficulties in the past and the apparatus 10 has been developed to assist in this regard.

[0020] The apparatus 10 includes a curved beam extension piece 32 which extends upwardly and then downwardly from an end 34 of the beam 16. The beam 16 is normally supported, inter alia, by a brace 36 which extends from fixed structure on the load bed to a point 38 which underlies the end 34 of the beam 16.

[0021] A guide 40 is positioned against the beam extension 32. The guide is made from an elongate length of smooth pipe which is bent into an extended curved U- form. Ends of the guide are attached at pivot points 42 to the brace 36. Two strut members 46 are secured to respective opposed sides of the guide and brace central upwardly extending sections 48 of the guide. Two supports 50 are positioned on opposing sides of the curved beam extension 32 and each is pivotally attached at a respective pivot point 52 to the corresponding strut member 46, and at a respective lower pivot point 54 to a corresponding rod 56 which, in turn, is pivotally attached to the brace 36 at a point 58.

[0022] A threaded shank 60 is pivotally attached to the point 38 and extends downwardly. A hand wheel 62 is threadedly engaged with the shank and acts against a plate 64 which bears on the supports 50 and the rods 56 at the pivot point

54. If the wheel is turned in one direction it urges the supports and rods upwardly and, as a consequence, the guide 40 is also moved upwardly. If the wheel is rotated in the opposing direction the guide is lowered relatively to the beam.

[0023] An electric motor 70 (shown in outline only) is fixed to the strut members 46. The electric motor is of conventional construction and operates via a suitable control, not shown, to drive a pair of sprockets 72 which are mounted for rotation about a common axis 74. An opposed pair of similar sprockets 76 is mounted for rotation about a common axis 78. Two endless chains 80 and 82 are engaged with the sprockets. As is shown in Figure 2 the chains are positioned on opposed sides of the beam extension 32 and are respectively flanked by lengths 84 of the guide 40.

[0024] Each chain has a plurality of outwardly extending catch members 90 fixed to it. Each catch member is mounted for pivotal movement about a respective pivot point 92, on the chain, and a coil spring 94, which is centred on the pivot point 92, is placed in a predetermined state of tension and biases the catch member 90 forwardly, relatively to the chain, in a direction 96 (see the inset drawing in Figure 3) i.e. in a "forward" direction of the vehicle.

[0025] When the compressed barrier on the beam 16 is to be deployed the hand wheel 62 is operated to drop the motor and chain conveyor assembly downwardly to the dotted line position snown in Figure 1. The catch members are then substantially lower than the uppermost surface of the beam extension 32 and the adjacent surfaces of the guide 40. The circular coils of the barrier can therefore be moved across the beam extension 32 without risk of the catch members fouling, or otherwise engaging with, the barrier. In other words it is possible for the barrier to be deployed from the vehicle in a conventional manner.

[0026] If the barrier is to be recovered then the hand wheel is operated to raise the guide and chain conveyor assembly upwardly to the solid line position shown in Figure 1. As is evident particularly from Figure 2 the uppermost extremities of the catch members are then higher than the uppermost adjacent surfaces of the beam extension 32 and of the adjacent sections 84 of the smooth guide 40. The vehicle is reversed so that a lowermost end 100 of the curved beam extension is moved into the interior of the uppermost coil 24 which is to be recovered. The motor 70 is then operated and the chain conveyors are driven in unison in the direction of an arrow 102. If necessary the vehicle is slowly reversed further towards the barrier and the catch members are thereby brought into contact with upper sections of the uppermost coil 24. The catch members are moved in the direction 102 and sections of the uppermost coil are thereby progressively brought, in succession, onto the curved beam extension 32.

[0027] The forces which are exerted by the coil springs 94 in the relevant catch members are sufficiently high to ensure that the barrier is pulled upwardly along the curved beam extension and passes over a hump 104. Thereafter the barrier sections move downwardly towards the end 34 of the beam 16. At this point the chain conveyor moves downwardly relatively to the beam extension 32 and there is a natural tendency for the catch members to disengage from the coils in the barrier. Nonetheless as the windings of the coil 24 become stacked on the beam 16 considerable resistance to movement occurs and, as a consequence, at least one of the catch members may tend to remain engaged with windings of the coil 24.

[0028] When this occurs the respective catch member can be subjected to considerable force. However once the catch member is subjected to a force which is excess of the biasing force exerted by the corresponding coil spring 94 the catch member deflects about its pivot point in a second direction 106, which opposes the direction 96. It is therefore possible for the catch member to deflect and, in this way, the catch member is disengaged from the uppermost coil 24.

[0029] During the aforementioned process, particularly as an increasing number of windings of the upper coil 24 is moved onto the beam 16, it may be necessary for an operator to move the windings of the coil 24 along the beam 16 away from the chain conveyors ie. to the right in Figure 1. This can be done manually or in any appropriate way for example by using hook-shaped implements which are engaged with the windings and which allow the windings to be physically drawn along the beam 16.

[0030] It has been found that, by allowing the catch members to deflect about the pivot points once they are subjected to loading forces in excess of a predetermined value, a highly effective coil recovery operation is achieved. The windings, between successive catch members, ride on uppermost surfaces of the beam extension and the guide and the likelihood of the windings fouling on these components is, for practical purposes, negligable. [0031] During the recovery operation it is normally necessary for the vehicle to be reversed towards the barrier, which is lying on the ground, for the force which is otherwise needed to draw the barrier onto the curved beam extension 32 can be considerable.

[0032] Figure 5 illustrates, somewhat schematically, apparatus 10A, generally of the type described hereinbefore, mounted to a beam 16A of a suitable recovery vehicle.

[0033] The beam 16A is similar to the beam 16 but the apparatus 10A is elongated, in the direction of the beam 16A, and is positioned not on the curved extension piece 32 but rather on a longer substantially horizontally extending section 16B of the beam.

[0034] In other respects the apparatus 10A is substantially the same as the apparatus 10 and functions in the same way. However it is necessary to ensure that the beam extension 32 is fully inserted into the uppermost coil (not shown) which is to be recovered and that the catch members 90 are engaged with upper sections of the uppermost coil 24. In general terms the catch members will be engaged with a larger number of windings in the uppermost coil than what is the case, for example, in the Figure 4 embodiment and the catch members will continuously be moved into engagement with, and out of engagement from, the windings. This is because the windings will be stacked in compressed form over the apparatus as the coils are recovered. As a larger number of catches are engaged with the windings than in the Figure 4 embodiment each coil spring will generally have a lower force of deflection than what is the case with the smaller apparatus 10 shown in Figure 4. Nonetheless the effectiveness of recovery is substantially the same, with the Figure 5 arrangement having the advantage that it is capable of compressing the coils, to a substantial extent, on the beam section 16B.

[0035] The apparatus 10A could also be shortened, to a length X, which is significantly less than the length Y of the beam section 16B. Another possibility is to use the apparatus 10A on the section 16B, with the apparatus 10 on the beam extension 32.

[0036] Figure 6 illustrates a further arrangement wherein apparatus 10C, similar to the apparatus 10, is constructed so that it can be secured to tines of a fork lifter 120 or by means of a suitable framework 122 directly to structure 124 to which the tines are normally attached. The tines, if used, may be extended in the horizontal

direction as appropriate and the apparatus 10C may be positioned at any appropriate point on the tines or extend the full length of the tines. The use of the fork lifter has the particular benefit that the fork lifter can be manoeuvred, as required, so that a leading end of a beam extension 32A (if used), or a leading end of the apparatus 10C, can be inserted into the interior of the uppermost coil 24 of a barrier wherein the coil 24 rests on underlying coils 20 and 22, as shown in Figure 2. This engagement action can more readily be accomplished by adjusting the height of the apparatus, as necessary, as is indicated by a double arrow 130 in Figure 7.

[0037] The barrier is then collected in the manner shown in Figure 7. A twofold action results in that the apparatus is used for drawing the barrier onto a collector beam 16D in the manner which has been described, while at the same time the fork lifter 120 is capable of being moved continuously towards the barrier in the direction of an arrow 132, and vertically if required so that the collection or recovery process is facilitated. [0038] The motor 70 which is used to drive the apparatus 10C may be powered by means of a motor generator set 134 which is mounted to the fork lifter at any appropriate location.

Claims

1. Apparatus for recovering an elongate, extended, flexible, coil barrier which includes a beam, and a conveyor which includes at least one support which is positioned adjacent at least a portion of the beam, a plurality of catch members which are pivotally attached at spaced intervals to the support, and a drive mechanism for driving the support whereby the catch members are successively engageable with respective sections of the barrier thereby to draw the sections in succession onto the beam characterised in that a plurality of biasing devices are respectively associated with the catch members, with each biasing device being mounted to bias a respective catch member in a first direction relatively to the support and in that each catch member is pivotally deflectable relatively to the support in a second direction opposite to the first direction against the biasing action of the respective biasing device if force which is exerted on the catch member, as a result of its engagement with the barrier, exceeds a force exerted on the catch member by the respective biasing device.

2. Apparatus according to claim 1 wherein the at least one support is an endless flexible element.

3. Apparatus according to claim 1 which includes two of the supports which respectively comprise two elongate lengths of chain which are closed loops and which are positioned on respective opposed sides of the beam substantially parallel to each other and each chain includes a plurality of the catch members.

4. Apparatus according to claim 1 wherein each catch member has an extremity which is moved to a point which is higher than an adjacent uppermost surface of the beam as the support is driven by the drive mechanism.

5. Apparatus according to claim 1 wherein the at least one support is mounted for limited pivotal movement about a horizontal axis.

6. Apparatus according to claim 1 which is mounted on a load bed of a vehicle and wherein a guide is positioned adjacent the conveyor, at least at a location which is near a free end of the beam, with the catch members being positioned between the beam and the guide.

7. Apparatus according to claim 1 which is mounted to a vehicle which includes means for moving the apparatus to a limited extent in a vertical direction.

8. A method of recovering an elongate coiled barrier which includes the steps of directing a guide into coils at one end of the barrier, engaging catch members on a conveyor with uppermost sections of the coils, and actuating the conveyor to draw the barrier onto a support thereby to compress the coils on the support, and which is characterised by the step of allowing a catch member to deflect, to disengage from a respective coil section, if a force exerted on the catch member by the coil section exceeds a predetermined biasing force.