GB2478019A

GB2478019A - Chaff package assembly system

Info

Publication number: GB2478019A
Application number: GB1012834A
Authority: GB
Inventors: Stuart Cutler
Original assignee: Wallop Defence Systems Ltd
Current assignee: EST Defence Company UK Ltd
Priority date: 2010-07-30
Filing date: 2010-07-30
Publication date: 2011-08-24
Anticipated expiration: 2030-07-30
Also published as: GB2478019B; WO2012013954A1; GB201012834D0

Abstract

A chaff package is assembled by picking up a plurality of fibre bundles and placing the bundles into a compression means. The fibre bundles are then compressed to a diameter smaller than that of a fixed diameter sleeve. The compressed bundles are ten moved into the fixed diameter sleeve, the compressed bundles are supported at both ends, and the chaff package is ejected.

Description

CHAFF PACKAGE ASSEMBLY SYSTEM

Field of the Invention

The invention relates to chaff package assembly systems.

Background of the Invention

The closest prior art is the Applicant's own process of manually assembling chaff packages from an array of glass fibre sub-bundles. Each sub-bundle is cut by a guillotine to a predetermined length, typically 8 millimetres. Each glass fibre contained within the bundle is known as a dipole, therefore any reference to the fibres within the sub bundles will be known as dipoles.

This process incorporates the following steps: * Manually obtaining an array of sub-bundles and arranging them so that they are adjacent to each other.

* Manually compressing the sub-bundles by hand, and placing them into a first containing sleeve which is known as a "nest".

* Once the nest has been manually populated, it is then manually loaded into a diameter reducing apparatus, which incorporates a tapered device. The Manual activation of a cylindrical ram forces the nest sleeve through the tapered device, which reduces the diameter of the nest sleeve.

The converged sub-bundles exit the tapered device and are fed directly into a second over-wrapping sleeve. For example, an operator may manually load a nest which has a 50mm diameter. When the bundles are drawn through the tapered device, the diameter is reduced again to be loaded straight into a 40mm diameter sleeve.

The disadvantage of this process is that the cylindrical ram has the same diameter as the reduced exit aperture of the tapered device. Therefore, when the cylinder forces the nest sleeve through the tapered device, the dipoles located between the periphery of the cylinder and the containing sleeve are not adequately compressed. This results in a stepped outer ring being formed within the outer surface, at one end of the formed chaff package. The stepped outer ring is an undesired by-product of the assembly process, which has to be manually removed before the assembly process is completed. The removal requires an operator to manually tap/knock the formed chaff package against a flat surface so that the stepped outer diploes are adjusted within the containing sleeve, so that all the contained dipoles are at an even length, and the end surfaces have been dressed so that they are uniformly flat. The manual dressing of the formed chaff package is a labour intensive and inefficient process; this is not desirable as the process is already manually labour intensive.

Summary of the Invention

In a first broad independent aspect, the invention provides a system for assembling a chaff package comprising: * Means for picking up a plurality of fibre bundles and placing said bundles into a compression means; * Means for compressing said fibre bundles into a smaller diameter in relation to a fixed diameter sleeve which, in use, contains said compressed fibre bundles; * Means for moving said compressed fibre bundles into said fixed diameter sleeve to form said chaff package; * Means for supporting said compressed fibre bundles at both ends; and * Means for ejecting said chaff package.

The advantage of this configuration is that the chaff system provides a low cost, high volume solution to the assembly of chaff packages. The system provides a means of assembling a chaff package with multiple configurations and pack lengths without minimal setup or change over times.

Furthermore, the system provides a solution of automatically assembling chaff packages while maintaining a continued high level of throughput, which is not manually labour intensive. The system eliminates all the sub-assembly processes which require manual labour to prepare the chaff package for the next operation within the chaff assembly process. The system is able to provide fully assembled chaff packages, which require no subsequent rework or dressing of the contained dipoles to obtain the correct length of the package.

Preferably, said picking up and placing means is provided by a combined pick and place unit. This unit automatically picks up the fibre bundles and places them within the compression jaws of the machine at high speed. This contributes to providing the high volume assembly of the chaff packages through the machine.

Preferably, said fibre bundles are compressed to a diameter of substantially two millimetres less than said fixed diameter sleeve. This enables the automatic insertion of the compressed bundles into the fixed diameter sleeving without any direct interference from the sleeving.

Preferably, said compression means is provided by a plurality of jaws which locate about said fibre bundles. The jaws provide an automatic compression means for compressing the fibre bundles, which can be Loaded automatically.

More preferably, said jaws are interlocked together when in a closed configuration. The interlockable jaws provide means of automatically enclosing the fibre bundles, with out trapping any of the dipoles or containing sleeving between them.

More preferably, said jaws are powered by a high pressure actuator. The actuators provide the power to the compressor jaws which is required to compress the fibre bundles. The pressure required to compress the bundles is approximately 1.3 tonnes per square inch.

Preferably, said supporting means is provided by a plurality of cylinders which, in use, sandwiches said fibre bundles at both ends. This provides the automatic support of the fibre bundles, while they are being compressed.

More preferably, said plurality of cylinders compresses said fibre bundles to form the length of said chaff package. This enables the automatic "dressing" of the chaff pack so the contained dipoles are maintained at an even length and that the end surfaces are uniformly flat.

More preferably, said plurality of cylinders cooperate and move in tandem to facilitate the movement of said sandwiched fibre bundles into said fixed diameter sleeve. This enables the automatic transportation of the compressed fibre bundles into the containing sleeve.

Preferably, further comprising a cutting means which cooperates with said jaws and said cylinders and cuts said compressed fibre bundles while they are securely held in place. This enables the compressed bundles to be automatically cut into small lengths, typically 3 mm prior to being inserted into the containing sleeve.

More preferably, said cutting means is a die and press tooling. This provides a means of automatically cutting the compressed fibre bundles, which works in synergy with the compressor jaws and supporting cylinders.

In a second broad independent aspect, the invention provides a method of assembling a chaff package comprising the steps of: * Picking up a plurality of fibre bundles and placing said bundles into a compression means; * Compressing said fibre bundles into a smaller diameter in relation to a fixed diameter sleeve which, in use, contains said compressed fibre bundles; * Moving said compressed fibre bundles into said fixed diameter sleeve to form said chaff package; * Supporting said compressed fibre bundles at both ends; and * Ejecting said chaff package.

Preferably, comprising a further step of compressing both ends of said compressed fibre bundles to form the length of said chaff package.

Brief Description of the Drawings

Figure 1 shows a perspective view of the compressor jaws and holding cylinders.

Figure 2 shows a schematic view of the compressor jaws loaded with an array of glass fibre bundles.

Figure 3 shows a schematic view of the compressor jaws and holding cylinders in a configuration which encloses the configuration of the glass fibre bundles.

Figure 4 shows a schematic view of the holding cylinder moving the compressed fibre bundle into a containing sleeve.

Figure 5 shows a perspective view of an assembled chaff package.

Detailed Description of the Drawings

Figure 1 shows the two compressor jaws 2 and 3, and two cylindrical rams 4 and 5, which provide the essential features of a chaff package automation machine generally indicated by 1. The compressor jaws 2 and 3 are shown to be curved, to form a forming region within the compressor jaws 2 and 3 to facilitate the forming of loaded glass fibre bundles into an overall slug' configuration. Each compressor jaw 2 and 3 incorporates an array of equally spaced "fingers" 6 and 7, which interlock together when compressor jaws 2 and 3 close together.

In use, two compressor jaws 2 and 3 are automatically loaded with an array of glass fibre bundles supplied from a pick and place unit. The glass fibre bundles are also known as sub-bundles. The pick and place unit (not shown) quickly loads the compressor jaws 2 and 9, which contribute to providing a high volume of assembled chaff packages through the machine 1. The pick and place unit provides a means of loading a set of bundles of different lengths in any predetermined multiple pack cut configurations and pack lengths, while maintaining a high volume throughput of the assembly of the chaff packs without minimal set up or change over times. The two compressor jaws 2 and 3 are operated by one or more high pressure cylinders/actuators and are used to automaticalLy compress the loaded glass fibre bundles down to a reduced diameter. The reduced diameter enables the compressed bundles to be inserted within a fixed diameter, containing sleeve to form the completed chaff package. The reduced diameter is typically 2 millimetres smaller than the "containing sleeving", which allows the compressed bundles to expand against the sleeve to form a tight friction fit.

Figure 2 shows an array of loaded glass fibre bundles 8 to 15. The bundles have been arranged into two horizontal rows 16 and 17, which are adjacent to each other. Each horizontal row 16 and 1 7 is formed from four glass fibre bundles of differing lengths. Each horizontal row 16 and 1 7 is symmetrical to the adjacent horizontal row.

In use, the gLass fibre bundles are automatically loaded by the pick and place unit in a predetermined configuration, which determines the frequency characteristics of the assembled chaff package.

Figure 3 shows the compressor jaws 2 and 3 in a closed configuration, which encloses and compresses the enclosed array of loaded glass fibre bundles. The two cylindrical rams 4 and 5 are shown to move in the directions indicated by arrows 18 and 19, which locate against both ends of the compressed array of glass fibre bundles.

In use, the jaws 2 and 3 are linked and interLocked together so that they compress the enclosed array of glass fibre bundles into one slug' of compressed glass fibre, which forms the overall chaff package. The two cylinders 4 and 5 automatically locate against both ends of the compressed array of glass fibre bundles to provide an automatic "dressing" of the chaff pack so the contained dipoles are maintained at an even length and that the end surfaces are uniformly flat.

Figure 4 shows the glass slugl 8 formed by the compressed bundles 8 to 1 5 being automatically transported from the closed compressor jaws 2 and 3, in a direction indicated by arrow 19. When the glass slugl8 vacates the compressor jaws, it is inserted into a fixed diameter sleeve 20. The slug 18 is transported between two cylinders 4 and 5, in a tandem configuration that presses / transports the compressed glass fibre bundles 8 to 1 5 into the fixed diameter sleeve 20. The completed chaff pack is then automatically ejected from the machine 1.

Figure 5 shows a completed chaff package which has been formed by compressing an array of glass fibre bundles 21 into a glass slug, contained within a fixed diameter sleeve 20. The fixed diameter sleeve 20 is typically a mandrel wound sleeve, manufactured from a bi-axially oriented polyethylene terphthalate film, such as Mylar TM In an alternative embodiment of the invention, the chaff package automation machine further incorporates a specially ground die set and press tooling. The die and press tooling enable the manufacture of the chaff packages, which incorporate compressed glass fibre bundles cut to small lengths, typically about 3mm in length; this process is known as "millimetric cuts". The compressor jaws and two supporting end cylinders hold the wrapped chaff fibres in place whilst the die set engages the chaff package through the jaws and cuts the chaff fibres whist they are held securely in place. This tightly controls the cut length and quality. The cuts are then moved into the "fixed diameter sleeving" as per the previous embodiment.

Claims

Claims 1. A system for assembling a chaff package comprising: * Means for picking up a plurality of fibre bundles and placing said bundles into a compression means; * Means for compressing said fibre bundles into a smaller diameter in relation to a fixed diameter sleeve which, in use, contains said compressed fibre bundles; * Means for moving said compressed fibre bundles into said fixed diameter sleeve to form said chaff package; * Means for supporting said compressed fibre bundles at both ends; and * Means for ejecting said chaff package.
2. A system in accordance with claim 1, wherein said picking up and placing means is provided by a combined pick and place unit.
3. A system in accordance with either of the preceding claims, wherein said fibre bundles are compressed to a diameter of substantially two millimetres less than said fixed diameter sleeve.
4. A system in accordance with any of the preceding claims, wherein said compression means is provided by a plurality of jaws which locate about said fibre bundles.
5. A system in accordance with claim 4, wherein said jaws are interlocked together when in a closed configuration.
6. A system in accordance with either of claims 4 and 5, wherein said jaws are powered by a high pressure actuator.
7. A system in accordance with any of claims 1 to 6, wherein said supporting means is provided by a plurality of cylinders which, in use, sandwiches said fibre bundles at both ends.
8. A system in accordance with claim 7, wherein said plurality of cylinders compresses said fibre bundles to form the length of said chaff package.
9. A system in accordance with either of claims 7 and 8, wherein said plurality of cylinders cooperate and move in tandem to facilitate the movement of said sandwiched fibre bundles into said fixed diameter sleeve.
10. A system according to any of claims 7, 8 or 9 when dependent from any of claims 4,5 and 6, further comprising a cutting means which cooperates with said jaws and said cylinders and cuts said compressed fibre bundles while they are securely held in place.
11. A system according to claim 10, wherein said cutting means is a die and press tooling.
12. A method of assembling a chaff package comprising the steps of: * Picking up a plurality of fibre bundles and placing said bundles into a compression means; * Compressing said fibre bundles into a smaller diameter in relation to a fixed diameter sleeve which, in use, contains said compressed fibre bundles; * Moving said compressed fibre bundles into said fixed diameter sleeve to form said chaff package; * Supporting said compressed fibre bundles at both ends; and * Ejecting said chaff package.
13. A method in accordance with claim 12, comprising a further step of compressing both ends of said compressed fibre bundles to form the length of said chaff package.
14. A system for assembling a chaff package as hereinbefore described and/or illustrated in any appropriate combination of the accompanying text and/or Figures.
1 5. A method of assembling a chaff package as hereinbefore described and/or illustrated in any appropriate combination of the accompanying text and/or Figures.