Apparatus and method for filament winding cylindrical bodies with closed end

Claim 3

A method as claimed in claim 1 wherein the curing time of the resin is selected to be greater than the time taken to wind the complete hollow body.

Claim 4

A method as claimed in claim 2 wherein the filament retainers are upstanding spigots and upon completion of winding the body and before curing of the resin, circumferential rovings are wound on one or both sides of the spigots and the spigots then removed.

Claim 5

A method as claimed in claim 3 wherein the body is rotated after removal of the spigots until curing of the resin is substantially complete, such that resin migration fills the holes left by the spigot removal in a substantially uniform manner.

Claim 6

A method as claimed in claim 4 wherein after curing of the resin a recess groove is formed along the line of the spigots and then the groove is filled by winding in further filaments as a guard against porosity.

Claim 7

A filament winding machine for winding cylindrical bodies closed at one end thereof, said machine comprising means to support a former, filament guide means to guide at least one filament in spaced relationship to the former, means to reversibly move the filament guide means relative to the former such that the filament guide means traverses the length of the former and means to rotate the former relative to the filament guide means about an axis parallel to the traversing movement, wherein the improvement lies in that: the former is secured to a support at one axial end, the remote end being free; a circumferential array of filament retainers is attached to the periphery of the former near said remote end to limit slippage of the filament as it is laid between pairs of adjacent filament retainers; and the means to move the filament guide means traverses to a position beyond said remote end of the former whereby the filament is wound over the end of the former.

Claim 8

A filament winding machine for winding cylindrical bodies closed at one end thereof, said machine comprising means to support a former, filament guide means to guide at least one filament in spaced relationship to the former, means to reversibly move the filament guide means relative to the former such that the filament guide means traverses the length of the former and means to rotate the former relative to the filament guide means about an axis parallel to the traversing movement, wherein the improvement lies in that: the former is secured to a support at one axial end, the remote end being free; a circumferential array of filament retainers is attached to the periphery of the former near said remote end to limit slippage of the filament as it is laid between pairs of adjacent filament retainers; and the means to move the filament guide means traverses to a position beyond said remote end of the former whereby the filament is wound over the end of the former.

Claim 9

A filament winding machine as claimed in claim 1 wherein the filament guide means comprises an annular spider supporting a plurality of circumferentially spaced filament guides whereby a plurality of filaments can be wound simultaneously onto the former.

Claim 10

A filament winding machine as claimed in claim 7 wherein the filament guides are distributed asymmetrically around the spider.

Claim 11

A filament winding machine as claimed in claim 8 wherein each filament guide includes a tensioning device.

Claim 12

A filament winding machine as claimed in claim 9 wherein each filament guide comprises a non-rotating satin-finished fairlead.

Claim 13

A filament machine as claimed in claim 10 wherein there is included a resin bath and means to splay out individual fibres of each multi-fibre filament to improve the resin loading of the filaments prior to laying on the former.

Claim 14

A filament winding machine as claimed in claim 6 wherein each filament guide includes a tensioning device.

Claim 15

A filament winding machine as claimed in claim 12 wherein the filament guide comprises a non rotating, satin-finished fairlead.

Claim 16

A filament winding machine as claimed in claim 13 wherein there is included a resin bath and means to splay out individual fibres of each multi-fibre filament to improve the resin loading of the filaments prior to laying on the former.