GB2140898A

GB2140898A - Weather proof canister

Info

Publication number: GB2140898A
Application number: GB08315031A
Authority: GB
Inventors: Henry Fitzgerald
Original assignee: Short Brothers PLC
Current assignee: Short Brothers PLC
Priority date: 1983-06-01
Filing date: 1983-06-01
Publication date: 1984-12-05
Also published as: GB2140898B

Abstract

The invention provides a means of keeping a missile in a weather-proof canister 10 until the moment of firing which avoids the dangerous debris from a sealing membrane 13 shattered by exit of the missile from the canister. An electrical resistance heating wire 19 is provided, in a sandwich structure of a membrane bonded around its periphery to the missile exit aperture 12, in a loop around the circumference of the aperture. The central part of the membrane is fastened to a hatch 15 which overlies the aperture. The firing sequence involves heating the wire so the central portion 14 of the membrane 13 is parted from its periphery and is then carried by the hatch 15 away from the aperture 12 in one piece which is not subsequently shattered by exit of the missile. <IMAGE>

Description

SPECIFICATION Weather proof canister This invention relates to a weather proof canister and, more particularly but not exclusively, to a weather proof canister for a missile.

Military missiles must be stored for long periods without deterioration, and one way of doing this is to provide the missiles in weather proof canisters from which they are fired. Sealing of the opening in the canister through which the missile is fired presents a problem in that, on the one hand, the quality of the seal should be unaffected by physical damage to the external surfaces of the canister as a whole yet, on the other hand, the sealing means should not be suchas to give rise to any debris arising from the swift departure of the missile from the opening. It is one object of the present invention to provide a solution to this problem.

According to the present invention there is provided a canister comprising wall surfaces which define an opening, through which any contents of the canister may leave the canister, and means to seal the opening against ingress of atmospheric moisture, characterised in that the sealing means comprises a sealing membrane and a hatch member, the sealing membrane having a peripheral portion which is bonded to the wall surfaces around the opening and a central portion which spans the opening, there being disposed between the central and peripheral portions a parting line which allows the outline of the opening, the hatch member, in a closing disposition, covering the opening and the external surface of. at least the central portion of the membrane to protect it against physical damage, the sealing means further comprising means to separate the two portions of the membrane along the parting line and a connection between the central portion and the hatch member whereby, when the hatch member moves from the closing disposition to an opening disposition in which it permits free passage of the contents out of the canister, the separated central portion of the membrane is also removed from the opening.

Preferably, the sealing membrane is laminated from plastics materials and the parting line is defined by an electrical resistance, heating wire sandwiched between adjacent layers of the sealing membrane and following the profile of the canister opening.

For a better understanding of the present invention, and to show more clearly how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figures 1,2 and 3 are similar, longitudinal, axial sections of part of a canister to contain a guided missile, the part of the canister which is shown being that which is adjacent to an opening in the canister through which a missile within the canister would be fired; and Figure 4 is a perspective view of the same part of the canister which is shown in the earlier Figures.

Referring to the drawings, a canister 10 has wall surfaces 11 which define an opening 12 at one end of the canister. The opening 12 is sealed against ingress into the canister 10 of atmospheric moisture by a sealing membrane 13, of which a peripheral portion 14 is bonded to the wall surfaces 11 and a central portion 14 spans the opening 12. A hatch member 15 is pivotably connected to the wall surfaces 11 at a hinge 16 for movement between a closing disposition (Figure 2) in which it covers the opening 12 and the membrane 13, and an opening disposition (Figure 3) in which it permits free passage of the missile out of the canister. During storage of the canister and its contents, the hatch member 15 is secured to the wall surfaces 11 by clamps, toggles, or other conventional means (not shown).

Referring now to Figure 1, there are bonded to the external surface of the central portion 14 of the membrane 12, a pair of anchor lines 17. These pass through small apertures 18 in the hatch member 15.

After the membrane 13 has been bonded to the wall surfaces 11, the anchor lines 17 are threaded through the apertures 18 as the hatch member 15 is moved to its closimg disposition. With the hatch member in this disposition, the anchor lines are tightened and then secured to the outer surface of the hatch member as shown in Figure 2.

Within the thickness of the membrane 13 is an electrical resistance, heating wire 19 which following the outline of the opening 12. One convenient way of providing the wire within the thickness of the membrane is to lay it between adjacent layers of a membrane of sandwich structure.

In use of the canister, the procedure to be followed when preparing the missile to be fired includes a step of actuating an electrical power supply to the resistance wire 19 so that the resultant heat generated by the wire burns away the membrane along the parting line. Because hatch member 15 does not in itself provide a weather proof seal, this burning away of the membrane along the parting line breaks the weather proof seal of the canister at the opening 12.In a subsequent step of the firing sequence, the hatch member 15 is moved from the closing to the opening disposition, that is to say, from the disposition shown in Figure 2 to that shown in Figure 3 and, by virtue of the separation of the central portion 4 of the membrane from its peripheral portion 14, and the connection between the central portion 14 and the hatch member 15 through the anchor lines 17, the central portion 14 is carried by the hatch member 15 out of the opening 12 to allow free passage of the missile. Because both the central and peripheral portions of the sealing membrane 13 remain securely fastened to the hatch member 15 and the wall surfaces 11 respectively, it is ensured that the membrane 13 does not give rise to any dangerous, flying debris.

CLAiMS

1. A canister comprising wall surfaces which define an opening, through which any contents of the canister may leave the canister, and means to seal the opening against ingress of atmospheric

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Weather proof canister This invention relates to a weather proof canister and, more particularly but not exclusively, to a weather proof canister for a missile. Military missiles must be stored for long periods without deterioration, and one way of doing this is to provide the missiles in weather proof canisters from which they are fired. Sealing of the opening in the canister through which the missile is fired presents a problem in that, on the one hand, the quality of the seal should be unaffected by physical damage to the external surfaces of the canister as a whole yet, on the other hand, the sealing means should not be suchas to give rise to any debris arising from the swift departure of the missile from the opening. It is one object of the present invention to provide a solution to this problem. According to the present invention there is provided a canister comprising wall surfaces which define an opening, through which any contents of the canister may leave the canister, and means to seal the opening against ingress of atmospheric moisture, characterised in that the sealing means comprises a sealing membrane and a hatch member, the sealing membrane having a peripheral portion which is bonded to the wall surfaces around the opening and a central portion which spans the opening, there being disposed between the central and peripheral portions a parting line which allows the outline of the opening, the hatch member, in a closing disposition, covering the opening and the external surface of. at least the central portion of the membrane to protect it against physical damage, the sealing means further comprising means to separate the two portions of the membrane along the parting line and a connection between the central portion and the hatch member whereby, when the hatch member moves from the closing disposition to an opening disposition in which it permits free passage of the contents out of the canister, the separated central portion of the membrane is also removed from the opening. Preferably, the sealing membrane is laminated from plastics materials and the parting line is defined by an electrical resistance, heating wire sandwiched between adjacent layers of the sealing membrane and following the profile of the canister opening. For a better understanding of the present invention, and to show more clearly how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figures 1,2 and 3 are similar, longitudinal, axial sections of part of a canister to contain a guided missile, the part of the canister which is shown being that which is adjacent to an opening in the canister through which a missile within the canister would be fired; and Figure 4 is a perspective view of the same part of the canister which is shown in the earlier Figures. Referring to the drawings, a canister 10 has wall surfaces 11 which define an opening 12 at one end of the canister. The opening 12 is sealed against ingress into the canister 10 of atmospheric moisture by a sealing membrane 13, of which a peripheral portion 14 is bonded to the wall surfaces 11 and a central portion 14 spans the opening 12. A hatch member 15 is pivotably connected to the wall surfaces 11 at a hinge 16 for movement between a closing disposition (Figure 2) in which it covers the opening 12 and the membrane 13, and an opening disposition (Figure 3) in which it permits free passage of the missile out of the canister. During storage of the canister and its contents, the hatch member 15 is secured to the wall surfaces 11 by clamps, toggles, or other conventional means (not shown). Referring now to Figure 1, there are bonded to the external surface of the central portion 14 of the membrane 12, a pair of anchor lines 17. These pass through small apertures 18 in the hatch member 15. After the membrane 13 has been bonded to the wall surfaces 11, the anchor lines 17 are threaded through the apertures 18 as the hatch member 15 is moved to its closimg disposition. With the hatch member in this disposition, the anchor lines are tightened and then secured to the outer surface of the hatch member as shown in Figure 2. Within the thickness of the membrane 13 is an electrical resistance, heating wire 19 which following the outline of the opening 12. One convenient way of providing the wire within the thickness of the membrane is to lay it between adjacent layers of a membrane of sandwich structure. In use of the canister, the procedure to be followed when preparing the missile to be fired includes a step of actuating an electrical power supply to the resistance wire 19 so that the resultant heat generated by the wire burns away the membrane along the parting line. Because hatch member 15 does not in itself provide a weather proof seal, this burning away of the membrane along the parting line breaks the weather proof seal of the canister at the opening 12.In a subsequent step of the firing sequence, the hatch member 15 is moved from the closing to the opening disposition, that is to say, from the disposition shown in Figure 2 to that shown in Figure 3 and, by virtue of the separation of the central portion 4 of the membrane from its peripheral portion 14, and the connection between the central portion 14 and the hatch member 15 through the anchor lines 17, the central portion 14 is carried by the hatch member 15 out of the opening 12 to allow free passage of the missile. Because both the central and peripheral portions of the sealing membrane 13 remain securely fastened to the hatch member 15 and the wall surfaces 11 respectively, it is ensured that the membrane 13 does not give rise to any dangerous, flying debris. CLAiMS

1. A canister comprising wall surfaces which define an opening, through which any contents of the canister may leave the canister, and means to seal the opening against ingress of atmospheric moisture characterised in that the sealing means comprises a sealing membrane and a hatch member, the sealing membrane having a peripheral portion which is bonded to the wall surfaces around the opening and a central portion which spans the opening, there being disposed between the central and peripheral portions a parting line which follows the outline of the opening, the hatch member in a closing disposition covering the opening and the external surface of at least the central portion of the membrane to protect it against physical damage, the sealing means further comprising means to separate the two portions of the membrane along the parting line and a connection between the central portion and the hatch member whereby, when the hatch member moves from the closing disposition to an opening disposition in which it permits free passage of the contents out of the canister, the separated central portion of the membrane is also removed from the opening.

2. A canister as claimed in claim 1 wherein the contents is a missile.

3. A canister as claimed in claim 2 containing a military missile.

4. A canister as claimed in claim 1,2 or 3 wherein the sealing membrane is of plastics material.

5. A canister as claimed in any one of the preceding claims wherein the parting line is defined by an electrical resistance heating wire.

6. A canister as claimed in claim 6 wherein the membrane is laminated and the heating wire is sandwiched between adjacent laminations thereof.

7. A canister as claimed in any one of the preceding claims wherein the hatch member is secured in the closing disposition by clamps or toggles.

8. A canister as claimed in any one of the preceding claims wherein the hatch member is connected by hinges to the canister.

9. A canister as claimed in claim 8 wherein the central portion of the membrane is connected to the portion of the hatch member which overlies it when the hatch member is in a closing disposition by anchor lines for carrying the central portion out of the opening when the hatch member is moved to the opening disposition.

10. A canister substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.