GB2518373A

GB2518373A - Apparatus and method for moving a payload within a submarine

Info

Publication number: GB2518373A
Application number: GB1316588.1A
Authority: GB
Inventors: Robert Lovell
Original assignee: Babcock Integrated Technology Ltd
Current assignee: Babcock Integrated Technology Ltd
Priority date: 2013-09-18
Filing date: 2013-09-18
Publication date: 2015-03-25
Anticipated expiration: 2033-09-18
Also published as: GB201316588D0; GB2518373B

Abstract

A submarine payload movement arrangement comprises an apparatus operable to move a payload within a submarine to a payload delivery destination. The apparatus comprises a means 2 for moving a payload T, at least one chain (4, Fig 4), at least one sprocket (5, Fig 3) for driving the at least one chain and a power source 6 for driving the at least one sprocket. The means for moving a payload is coupled with the chain such that movement of the chain causes movement of the means for moving a payload. The at least one chain is provided with a plurality of rollers 41 and 42, the apparatus comprises a first chain guide (7, Fig 4) defining a path along which the at least one chain and rollers are movable, the chain guide inhibiting movement of the chain and rollers in a lateral direction and/or movement in a direction normal to a lateral direction and normal to the path. An arrangement where chain guides are formed as a single piece is also disclosed.

Description

Apparatus and method for moving a payload within a submarine

Field of the Invention

The present invention relates to an apparatus and method for moving payloads within submarines.

Background of -the invention

Payloads are moved into, out of, and around submarines in a variety of vays. For example, pulley systems may be used to lift payloads into a submarine. Hydraulic lifts may be used to -lift heavy items, such as torpedoes, from a storage area to a deployment area from which the torpedoes are moved into the torpedo tubes. Hydraulic rams are sometimes used to move torpedoes into the torpedo tubes. Such hydraulic-based systems are often heavy which is undesirable. Whilst such hydraulic-based systems are capable of moving payloads of high mass (such as torpedoes), they aae often not capable of moving high masses with precision. It is also sometimes difficult to control the movement of a ram. The present invention seeks to ameliorate one or more of the problems mentioned aboye.

Summary of the invention

In accordance with a first aspect of the present invention, there is provided an apparatus for moving a *payload within a submarine, the apparatus comprising a means for moving a payload, at least one chain, at least one sprocket for driving the at least one chain and a power source for driving the at least one sprocket; the means for moving a payload being coupled with the chain such that movement of the chain causes movement of the means for moving a payload.

The present invention provides an apparatus which may be relatively light and relatively inexpensive. Furthermore, control of the movement of the chain using the sprocket may be reasonably pztcise. For the avoidance of doubt, the teeth of the sprocket mesh with the chain.

The apparatus may comprise more than one chain and/or more than dna powered sprocket. Such an arrangement may be useful if the payload to be moved is particularly heavy. More than one sprocket nay be used to drive a single chain, for example, if the chain in question comprises parallel links.

The at least one sprocket is typically driveable in two directions, thereby being able to move the means for moving the payload in two directions (typically forwards and backwards or in apushing and pulling manner).

At least one chain may be a non-continuous chain i.e. a chain with two ends. Such a chain is lighter than a continuous loop of chain of the same gauge. If the chain has two ends, the chain may optionally have a length of no more than 5m, optionally no more than 4m and optionally no more than 3m. If the chain has two ends, the chain may optionally have a mass of no more than 40kg, no more than 32kg and no more than 24kg.

The apparatus may comprise a platform for receiving and supporting a payload. The platform may comprise one or more payload-receiving surfaces.

The apparatus of the present invention is optionally operable to move the payload in a straight line.

The apparatus may be operable to move a payload having a mass of at least 2000kg.

The apparatus May be operable to move a payload having a length of at least 2m, optionallyat least 4m and optionally up to 8m.

The apparatus may comprise a support for the means for moving S a payload. The support is optionally coupled to a chain so that movement of the chain causes movement of the support and therefore tthe means for moving a payload. The means for moving a payload may be removably coupled to said support. For example, the means for moving a payload may comprise a coupling configuration to couple with a corresponding configuration provided on the support. For example, the means for moving a payload may comprise one or more projections (such as lugs) which are received in a groove, aperture or recess provided in said support. In use, the support for the means for moving a payload is optionally generally above or below the means for moving a payload. In certain arrangements, the support for the means for moving a payload may generally be above the means for moving the payload. In other arrangements, the support for the means for moving a payload may generally be below the means for moving the payload Furthermore, if the means for moving a payload is elongate, the majority of the means for moving a payload may optionally be located forward of the support. In this case, forward may be defined, for example, by the location of a torpedo tube into which a payload is to be moved and/or a pushing direcflon. the support and means for moving a payload may optionally be located fqrward to the at least one sprocket.

The support may be located between the chain and the means for moving a payload.

The means for moving a payload may, in use, optionally be located rearward of the payload.

At least one chain may optionally be provided with a plurality of rollers. Optionally, at least one chain is provided with a plurality of rollers on one lateral side of the chain and a plurality of rollers on the other lateal side of the chain.

Rollers are optionally arranged to either lateral side of the chain. Each chain link may optionally be provided with a.

roller. At least one (optionally more than one and optionally each) roller is rotatably mounted on an axle. Rollers have proved to be effective in assisting in the smooth atid quiet movement of the chain. For the avoidance of doubt, the term "roller" includes wheels.

The apparatus may be provided with one or more chain guides, each defining a path along which a chain is movable, each chain guide inhibiting lateral movement of the chain (and rollers, if present) and/or movement in a direction normal to a lateral direction and normal to the path (thereby inhibiting chain "bounce"). For example, the apparatus may comprise *a first chain guide and a second chain guide. The first chain guide may be associated with the means for moving a payload.

For example, the first chain guide may be provided with a slot for the receipt and passage therethrough of a support for the means for moving a payload. The chain guide may provide a return chain guide.

If at least one chain is provided with a plurality of rollers, at least one chain guide may optionally comprise one or more running surfaces for the rollers. For example, if the apparatus comprises first and second chain guides, each of the first and second chain guides optionally comprises one or more running surfaces for the rollers. . . One or more chain guides may comprise one or more chain guide lengths, each length of chain guide being one-piece. For the avoidance of doubt, in this case each length of chain guide defines a path along which the chain is movable. If each length of chain guide is one-piece, said lengths are typically extruded. This enables the chain guides to be manufactured cheaply and with reduced weight. If the apparatus comprises first and second chain guides, one or both of the first and second chain guides may comprise one or more chain guide lengths, each length of chain guide being one-piece.

One or more chain guides may comprise a single (i.e. only one) length of chain guide. Alternatively, one or more chain guides may each comprise more than one length of chain guide, joined so as to form the respective chain guide.

One or more chain guides define a channel along which the chain (and rollers, if present) may be moved, at the same time constraining the chain and rollers (if present) so as to limit lateral and vertical movement. At least one chain guide may be provided with; or defines, a slot for the receipt of a support for the means fo moving a payload. Movement of the chain causes movement of the support and thereby movement of the means for moving a payload.

At least one chain guide may be shaped to inhibit lateral * movement of the chain (and rollers, if present) . Alteztatively of additionally, at least one chain guide may be provided with one or more side walls for inhibiting lateral movement of the chain (and rollers if present) At least one chain guide optionally comprises a base portion and optionally a portion which faces the base portion, the base portion (and the facing portion, if present) inhibiting movement of the chain (and rollers, if present) in a direction normal to a lateral direction and to the path. The base portion (and the facing portion, if present) help inhibit chain "bounce".

At least onechain guideis optionally elongate, and optionally comprises a base portion from which projects two side wall portions. Optionally, at least one chainguide comprises two inwardly-'projecting arms, defining a slot therebetween for the receipt and passage therethroagh of a support for the means for moving a payload. Each of the two inwardly-projecting arms may optionally project from a respective side-wall portion. Optionally at least part of, optionally the majority of and optionally all of at least one chain guide may be located forward of the at least one sprocket. "Forward" may be defined, for example, by the _______ location of a torpedo tube into which a payload is to be moved and/or a pushing direction.

The apparatus may be configured to move a payload into a torpedo tube of a submarine. The means for moving a payload in such a case is often known to those skilled in the art as a load bar.

The means for moving a payload may be elongate. The longitudinal axis may, in use, be essentially parallel to the direction of movement. The means for moving a payload may be substantially rigid so that any movement of the chain is transferred to a payload without significant deformation of the means for moving a payload.

The means for moving a payload may have an adjustable length.

This may be of assistance if the apparatus of the present invention is used to move payloads of more than one length.

The means for moving a payload may optionally comprise a means for pushing a payload. Such a means for pushing a payload would typically be coupled to the at least one chain so that the at least one chain is operable to move the means for pushing a payload (and thereby pushing a payload) . Such an arrangement typically moves a payload along a payload-supporting platform. The means for pushing a payload may further be suitable for pulling a payload, especially if the means for pushing a payload is attachable to a payload.

The means for pushing a payload, in use, typically exerts a force on the rear of a payload to urge the payload forwards.

The means for pushing, a payload optionally comprises a means for coupling to a payload. The means for coupling to a payload may comprise a male or female portion for coupling with a corresponding female or male portion provided on, a payload.

The means for coupling to a payload may comprise fastening means for attachment to a payload. The fastening means may, for example, be in the form of a pin, such as a cotter pin.

The means for pushing a payload may comprise a payload pushing assembly. The payload pushing assembly may be of adjustable length. The payload pushing assembly may be elongate; The longitudinal axis of the elongate' payload pushing assembly is optionally arranged to be substantially parallel to the pushing direction.

20' The power source for powerinq the sprocket may comprise a prime mover, such as a hydraulic motor. The at least one sprocket may be configured to be manually powered, for example, in the case of failure of transmission of electrical power to the at least one sprocket.

In accordance with asecondaspect of the present invention, there' is provided a submarine payload movement arrangement comprising an apparatus in accordahce with the first aspect of the present invention, optionally being loCated proximate to a payload delivery destination of the submarine, the apparatus being operable to deliver the payload to the payload delivery destination. The apparatus may be operable to deliver a payload to a torpedo tube.

In accordance ith a third aspect of the present invention, there is provided a submarine provided with an apparatus in accordance with the first aspect of the present invention and/or a submarine payload movement arrangement in accordance with the second aspect of the present invention.

In accordance with a fourth aspect of the present invention, there is provided a kit for the assembly of an apparatus in accordance with the first aspect of the present-invention, the kit comprising a means for moving a payload, at least one chain, at least one sprocket suitable to drive the at least one chain and a power source for driving the at least one sprocket, and a support for supporting the means for moving a payload and for coupling the means for moving a payload to the chain such that movement of the chain would cause movement -of the means for moving a payLoad. The kit of the fourth aspect of the present invention may comprise the features described above in relation to the apparatus of the first aspect of the present invention.

It will of course be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention.

Description of the drawings

Embodiments of the present invention will now be described by way of example only with reference to the following Figures of which: -Figure 1 is a schematic perspective view of part of an example of an apparatus in accordance with the present embodiment; Figure 2 is a schematic side-on view of the apparatus of Figure 1; Figure 3 is a side-on view of part of the apparatus of Figure 1 showing the relationship between the sprocket and a chain driven by the sprocket; Figure 4 is simplified end-on view of part of the apparatus of Figure 1 showing the relationship between the chain, rollers and track; Figure 5 is a plan view of the chain used in the apparatus of the present embodiment; Figure 6 is a cut-away perseative view ofa load bar used in the apparatus of Figure 1; Figure 7 is a schematic side-on view of a further example of an apparatus in accordance with the present invention; Figure Ba is a schematic end-on dross-section of a first chain guide used in the example apparatus of Figure 7; and Figure Bb is a schematic end-on cross-section of a second chain guide used in the example apparatus of Figure 7.

Detailed description

A first example of an apparatus and submarine paiload movement arrangement of the present invention will now be described principally with reference to Figures 1 to 5. Referring to Figure 1, the apparatus according to the embodiment is denoted generally by reference numeral 1. The apparatus 1 comprises *a load bar 2 mounted on a support 3 which is coupled to a movable chain 4, best seen in Figures 3 and 4. The movable bhain 4 is driven by two powered sprockets, one of which 5 is visible in Figure 3. The sprockets are driven by a hydraulic motor 6 which is visible in Figure 1. Very briefly, the hydraulic motor 6 drives a shaft (not shown) which rotates the sprockets 5 which, in turn, cause the chain 4 to move, thereby moving the support 3 and associated load bar 2. Movement of the load bar 2 causes movement of the payload, in this case a torpedo T, into a torpedo tube (not labelled) . The apparatus 1 will now be described in more detail.

The teeth not labelled) of sprockets 5 engage in the spaces formedin the links of the chain 4. The chain 4 has two ends i.e. it is not a loop of chain, but merely a length of chain in which the two ends are not attached to form a loop. In this case, chain 4 comprises two parallel connected chain portions 4a, 4b, each of which is driven by a respective sprocket. The chain is a Renold Synergy ® duplex roller chain (GY2OB2, Renold plc, Manchester, 13K) . The chain 4 is provided with a plurality of rollers, some of which are labelled 41, 42, 43, 44. Each roller is rotatably mounted on an extended bearing pin 45, as shown in Figure 5. A track 7 is provided to form a "run" for the rollers, as can best be seen from Figure 4, and a chain guide for the chain and rollers. The track 7 houses the chain 4, and the rollers, relatively snugly and provides support to the chain. The track 7 is shaped and sized to allow movement of the chain and rollers along the track, whilst limiting unwanted lateral and vertical movement. This arrangement allows transfer of a compression load to the chain without buckling the chain. The supporE 3 is attached to chain 4 so that when the chain 4 moves the support 3 moves too. The support 3 extends through a gap 71 provided in the track 7. A return track 77 is provided to house the chain and rollers when they are moved in a respective direction.

During use, the rollers contact track running surfaces 46, 47, and the rollers rotate relative to the axles on which they are mounted. The rollers facilitate the smooth and quiet running of the chain.

The structure and interaction of the load bar 2 and support 3 in relation to the torpedo T will, now be described in more detail with reference to Figures 1, 2 and 6. The load bar 2 is generally cylindrical in shape and comprises two lugs 21, 22, each of which is received in a respective channel 31, 32 provided in the upper portion of sflpport 3. The lugs' 21, 22 are located towards one end (the aft end) 23 of the load bar 2. The other end 24 (the fore end) of the load bar 2 is essentially tubular and provides an opening 25 for the insertion therein of a projection provided on the aft end of the torpedo T. The projection is typically known as a button B. On correct insertion of the button B into opening 25, a load bar pin insertion path is formed by apertures provided in the load bar 2 and a channel provided in button B. A load bar pin 206 is provided in the load bar ihsertion path to attach the torpedo T to the load bar 2. The attachment of the load bar 2 to the torpedo T ensures that any movement of the load bar is transferred to the torpedo T. For example, the attachment ensures that any movement in a fore to aft direction results in the torpedo T being pulled by the load bar2.

The support 3 is provided with a base 33 which provides stability in particular when the load bar 2 is attached. The lower surface of the base 33 is proximate to, or lightly contacts, supporting surfaces 41, 42. Support 3 is rigidly attaohed to chain 4 as shown in Figure 4 so that when the chain moves, the support 3 and load bar 2 move.

The load bar 2 used in the apparatus 1 will now be described in more detail with pa±ticular reference to Figure 6. The load bar 2 is adjustable in length which is particularly useful when a vessel is carrying payloads of more than one length, ince the length of the load bar can be adjusted to a length which suits the particular length of a payload. For example, mined are typically shorter than torpedoes, so a load bar for a mine may be longer than for a torpedo. Similarly, a boat may carry torpedoes of more than one length, in which case it may be useful to have a load bar of adjustable length.

Furthermore, the length of the chain 4 is finite, and it is desirable for the chain length to be as short as possible. In this case, the length of the load bar 2 may be *adjusted to take into consideration the movement range of the chain and payload length.

In the present case, the length of the load bar 2 is adjustable as follows. The load bar 2 comprises an inner tubular portion 26 generally disposed within an outer tubular portion 27. The inner tubular portion 26 is provided with a nut 28 bearing a screw thread (not shown) . The screw thread of nut 28 is coupled with a screw thread (not shown) of lead screw 29. Lead screw 29 is part of a threaded bar which is provided with a square headed portion 201 which can be used to cause rotation of lead screw 29. A bearing 207 is provided to facilitate rotation of lead screw 29. In use, a socket (not shown) having a recess for the recess of square headed portion 201 is placed over the square headed portion.201. A handle is used to rotate the socket which, in turn, rotates the square headed portion 201 and the lead screw 29. Rotation of lead screw 29 causes movement of nut 28 and thereby movement of inner tubular portion 26. The movement of inner tubular portion 26 causes the effective length of the load br 2 to be adjusted. The load bar 2 is further provided with an indicator 202 for indicating the length of the load bar 2. The indicator 202 is associated with the nut 28. A scale or markers (not shown) are provided on outer tubular portion 27! adjacent to indicator 202. The scale or markers indicate a particular length setting for a particular type of payload so that a user can adjust the length of the load bar 2 to suit the payload. A bush 204 is provided between the inner 26 and outer 27 portions of load bar 2 to allow sliding motion. An end stop 205 is provided on one end of lead screw 29 which abuts with a corresponding surface on nut 28 when the load bar 2 is fully extehded.

Operation of the apparatus 1 will now be described. A payload, in this case torpedoT, is delivered from a storage area to a position from which it is to be loaded into a torpedo tube.

The torpedo T rests on several inclinedsurfaces (not shown) *which provide a platform which supports the payload, as is well known to those skilled in the art. An angled plate 50 shown in Figure 1 is additionally provided to inhibit the torpedo T from rolling from its desired position. The support 3, without the load bar! 2 in position, is moved into approximately the correct position using the sprocket/chain arrangement. In order to position the load bar 2, button B of torpedo T in inserted into opening 25 of load bar 2 and the load bar manhandled onto support 3, typically with the lugs 21, 22 resting in position P shown as a dotted circle in Figure 2 (i.e. the load bar 2 is angled) . The support 3 is then moved forward using the sprockets so that the load bar 2 drops under the influence of gravity so that the load bar 2 is horizontal and lugs 21, 22 engage in the channels 31, 32 provided in the upper portion of support 3. The load bar pin 206 is then inserted to attach the torpedo T to the load bar 2. The sprocket/chain arrangement is then used to move the load bar 2 so as to push the torpedo into the torpedo tube.

Once the torpedo is in the desired Position, the load bar pin 206 is removed, thereby disconnecting the load bar from the payload. The torpedo T is then typically moved further into the torpedo tube ready for launching. The load bar is then moved rearwardly so that it is in position to push another payload into a torpedo tube.

While the load bar and payload are connected the load bar may be used to pull, as well as push, the payload. This may be desirable, for example, if it is no longer desirable to load the torpedo tube.

A further example of an apparatus for moving a payload in a submarine will now be described with reference to Figures 7, 8a and Sb. The apparatus is denoted generally be reference numeral 501 and comprises a chain 504 similar t chain 4 described above in relation to the apparatus of Figs. 1. to 6.

The chain 504 is coupled to a load bar support 503 which, in turn, is coupled to a load bar 502, in essentially the same manner as that described above in relation to the apparatus of Figs. 1 to 6. Rotation of sprocket 515 causes the chain 504 to move which, in turn, causes movement of load bar 502 which causes movemeht of the payload. The chain 504 is provided with rollers 505, 506 to facilitate smooth and quiet running of the chain. The apparatus 501 is provided with tracks 507, 577 which act as guides for the chain and rollers. Track 507 is associated with the load bar support 503 and is provided *with a slot 571 through which the load bar support 503 can project and be moved. Track 577 is a return track. There are differences between apparatus 1 arid apparatus 501 as will now be explained. Firstly, the track 507 associated with the load bar support and the load bar support 503 is located generally above the payload to be moved. This is in contrast to apparatus 1 in which the track 7 and load bar support 3 are generally below the payoad to be moved. Furthermore, both track 507 and return track 507 are single-piece tracks ot about Era in length and which are made by extruding steel. The resulting tracks are light and are made cheaply.

The example abOve illustrates the use of a non-continuous chain i.e. not a loop. A continuous loop of chain may be used.

The example above illustrates how the length of the load bar can be adjusted. The length of the load bar need not be

adjustable.

The example above illustrates the movement of a payload into a torpedo tube. Those skilled in the art will realise that the apparatus and method of the present invention may be used to move payloads more generally around the submarine (for example, introducing the payload into the submarine and for moving payloads laterally between stowage locations) The example above uses two sprockets ±o move the chain. Those skilled in the art will realise that a different number of sprockets may be used. For example, one sprocket may be used.

Alternetively, two independently-driven sprockets may be used instead of the two sprockets being driven by one shaft.

Furthermore, the example above uses one chain. Those skilled in the art will realise that more than one chain may be used.

Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. fleference should be made to the claims for determining the true scope of the present invention, which-should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that, integers or features of the invention that are described as preferable, advantageous, convenient or the like are ---optional and do not limit the scope of the independent claims.

Claims

Claims 1. A submarine payload movement arrangement comprising an apparatus operable to move a payload within a submarine to a payload delivery destination, the apparatus comprising a means for moving a payload, at least one chain, at least one sprocket for driving the at least one chain and a power source for driving the at least one sprocket; the means for moving a payload being coupled with the chain such that movement of the chain causes movement of the meatis for moving a payload, At least one chain being provided with a plurality of rollers, the apparatus comprising a first chain guide defining a pathalong which the at least one chain and rollers are movable, the chain guide inhibiting movement of the chain and rcllers in a lateral direction and/or movement in a direction normal to a lateral direction and normal to the path.
2. A submarine payload movement arrangement according to claim 1 wherein the first chain guide comprises one or more running surfaces for the rollers.
3. A submarine payload movement arrangement accQrding to claim 1 or claim 2 wherein the apparatus is operable to move a payload into a torpedo tube.
4. A submarine payload movement arrangement according to any preceding claim wherein the -at least one sprocket is -driveable -in two directions corresponding to a pushing and a pulling of a payload. --
5. A submarine payload movement arrangement according to any preceding claim wherein the means for moving a payload comprises a means for pushing a payload.
6. A submarine payload movement arrangement according to claim 5 wherein the means for pushing a payload is coupled to the at least one chain sc that the at least one chain is operable to move the means for pushing a payload, Sand thereby push the payload to a payload delivery destination.
7. A submarine payload movement arrangement according to claim 5 or claim 6 wherein the means for pushing a payload, in use, exerts a force on the rear of a payload to urge the payload forwards.B. A submarine payload movement arrangement according to any of claims 5 to 7 wherein the means for pushing a payload comprises a means for coupling to a payload.9. A submarine payload movement arrangement according to claim B wherein the means for coupling to a payload comprises a male or female portion for coupling with a corresponding female or male portion provided on a payload.10. A submarine payload movement arrangement according to claim 8 or claim 9 wherein the means for coupling to a payload comprises fastening means for attachment to a payload.11. A submarine payload moyement arrangement according to any of claims 5 to 10 wherein the means for pushing a payload comprises a payload pushing assembly ofadjustable length.12. A submarine payload movement arrangement according to claim 11 wherein the longitudinal axis of the payload pushing assembly is substantially parallel to the pushing direction. - 13. A submarine payload movement arrangement according to any preceding claim wherein at least one chain has two ends.14. A submarine payload movement arrangement according to claim 13 wherein the chain with two ends has a length of no more than Sm.15. A submarine payload movement arrangement according to claim 13 or claim 14 wherein the chain with two ends has a mass of no more than 40kg.16. A submarine payload movement arrangement according to any preceding claim wherein the first chain guide defines a channel along which the chain and *rollers are movable.17. A submarine payload moyement arrangement according to any preceding claim wherein the chain guide is provided with, Cr defines,, a slot for the receipt of a support for the means for moving the payload.18. A submarine payload movement arrangement according to any preceding claim wherein the first chain guide is elongate and comprises a base portion from which projects two side wall portion.19. A submarine payload movement arrangement according to claim 18 when dependent on claim 17 wherein the first chain guide comprises two inwardly-projecting arms, defining said slot therebetweei-i.* 20. A submarine payload movement arrangement according to any preceding claim wherein the payload delivery destination is defined as being in a forward direction, * and the majority of the track is located forward of the at least one sprocket.21. A submarine payload movement arrangement according to any preceding claim comprising a second chain guide defining a path along which a chain is movable, t'he second chain guide. inhibiting movement of the chain and rollers in a direction lateral of the at least one chain and/or in a direction normal to said, lateral direction and normal to the path.22. A submarine paylbad movement arrangement according to any preceding claim wherein one or both of the first and secbnd chain guides comprises one or more chain guide lengths, each length of chain guide being one-piece.23. A submarine payload movement arrangement according to claim 22 wherein each length of chain guide has been extruded.24. A submarine payload thovement arrangement according to any preceding claim wherein the apparatus is operable to move a payload in a straight line.25. A submarine payload movement arrangement according to any preceding claim operable to move a payload having a mass of at least 2000kg and a length of at least 2m.26. A submarine payload movement arrangement according to any preceding claim comprising a support for the means for moving a payload.27., A submarine payload movement arrangement according to claim 26 wherein the support is coupled to a chain so that movement of the chain causes rñovement of the support and the means for moving a payload.28. A submarine payload movement arrangement according to claim 27 whereih the means for moving a payload may be renovably coupled to.said support.29. A submarine payload movement arrangement according to claim 28 wherein the means for moving a payload comprises a coupling configuration to couple with a corresponding configuration provided on the support.30. A submarine payload movement arrangement according to any of claims 26 to 29 wherein the payload delivery destination is defined as being in a forward direction and the means for moving a payload is elongate, the majority of the means for moving a payload being located forward of the support.31. A submarine payload movement arrangement according to any of claims 26 to 30 wherein the payload delivery destination is defined as beihg in a forward direction and the support and means for moving a payload are located forward to the at least one sprocket.32. A submarine payload movemeht arrangement according to any preceding claim wherein the payload delivery detination is defined as being in a forward direction and the means for moving a payload is located rearward of a payload.33. A submarine payload movement arrangement according to any preceding ciajm wherein the means for moving a payload has an adjustable length.34. A submarine payload rñovement arrangement comprising an apparatus operable to move a payload within a submarine to a payload delivery destination, the apparatus comprising a means for moving a payload, at least one chain, at least one sprocket for driving the at least one chain and a power source for driving the at least one sprocket; the means for moving a payload being coupled with the chain such that movement of the chain causes movement of the means for moving a payload, the apparatus comprisihg a one or more chain guides defining a path along which the at least one chain is movable, movement of the chain along said path being associated with movement of the means for moving a payload, the one or more chain guide inhibiting movement of the chain in a lateral direction lateral and/or movement in a direction normal to a lateral direction and normal to the path, wherein at least one chain guide comprises one or more lengths of chain guide, each length of chain guide being one-piece.35. A submarine payload movement arrangement according to claim 34 comprising first and second chain guides, at least one of the first and second chain guides comprising one or more lengths of chain guide, each length of chain guide being one piece.36. A submarine payload arrangement according to claim 35 wherein the first chain guide is provided with a slot for the receipt, and passage therethrough, of a support for the means for moving a payload.37. A submarine payload arrangement according to claim 36 wherein the second chain guide comprises one or more lengths of chain guide, each length bf chain guide being one piece.38. An apparatus for moving a payload within a submarine suitable for use in the submarine payload movement arrangethent according to any preceding claim.39. A submarine provided with an apparatus in accordance with claim 38 or a submarine payload, movement arrangement according to any of claims 1 to.37.40. A kit for the assembly of an apparatus in accordance with claim 38, the kit comprising a means for moving a payload, at least one chain, at least one sprocket, suitable to drive the at least one chain and a power source for driving the at least one sprocket, and a support for supporting the means for moving a payload and for coupling the means for moving a payload to the chain such that movement of the chain would cause movement of the means for moving' a payload.