Cellular core

Claim 2

In a structural member of the type comprising a metal cellular core sandwiched between two parallel metal skin sheets, the improvement which comprises: a ceLlular core formed of interconnected corrugated metal ribbons comprising a plurality of identical interconnected core cells, all of which are identically configured, arranged in a matrix pattern and defining a core plane having a specified height, each of said identical core cells established by directly connecting, only at corrugation nodes, alternated and interleaved first and second type ribbons having respectively large corrugations and small corrugations, each of said identical cells being defined by a. a single large corrugation of said first type ribbon having two relatively large flat rectangular sections separated by a relatively small flat intermediate rectangular section angled with respect to said large sections, said both sections having a height measured normal to said core plane which is equal to the height of said cellular core, b. an integral number, in excess of one, of small corrugations of said second type ribbon, each corrugation having three flat interconnecting rectangular sections with the height of each section equal to the height of said cellular core, adjacent ones of said three interconnecting sections being angled relative to each other, and the area of any one of said rectangular sections of the corrugations of said second type ribbon being less than the area of said large rectangular sections of the corrugations of said first type ribbon, and c. said alternated and interleaved interconnected ribbons of said first and second type forming a plurality of identical cells, each of said identical cells being of generally triangular configuration, each of said skin sheets being secured to the edges of said ribbons, between which edges the core height is measured, to orient the axes of the core cells perpendicularly to the plane of said skin sheets.

Claim 3

A structural member of the type having sandwiched between two parallel metal skin sheets a metal cellular core characterized by a high degree of formability, comprising: a pair of faces of thin sheet metal stock, a plurality of first elongated metal ribbons disposed substantially parallel to each other, said first ribbons each having corrugations which include periodic nodes interconnected by ribbon sections, with the corrugations of said first ribbons having the same phase, pitch and amplitude, and the same height measured between opposite edges thereof, a plurality of second elongated metal ribbons disposed substantially parallel to each other, each of said second ribbons having corrugations which include periodic nodes interconnected by ribbon sections, with the corrugations of said second ribbons having the same phase, pitch and amplitude, and the same height measured between opposite edges thereof, the height of said second ribbons being equal to the height of said first ribbons, said first and second ribbons being secured at said opposite edges thereof to said faces with the planes of said ribbons being generally perpendicular to said faces, the ratio of said pitch of said first ribbons to said pitch of said second ribbons being an integer greater than one and of relatively low value, the ratio of said amplitude of said first ribbons to said amplitude of said second ribbons being greater than one and of relatively low value, and said first ribbons being alternated and interleaved and in phase with said second ribbons, with said alternated and interleaved first and second ribbons being joined to each other only at nodes thereof, providing a plurality of identical cells of generally triangular configuration having their axes perpendicular to said faces.

Claim 4

A structural member of the type having sandwiched between two parallel metal skin sheets a metal cellular core characterized by a high degree of formability, comprising: a pair of faces of thin sheet metal stock, a plurality of first elongated metal ribbons disposed substantially parallel to each other, said first ribbons each having corrugations which include periodic nodes interconnected by ribbon sections, with the corrugations of said first ribbons having the same phase, pitch and amplitude, and the same height measured between opposite edges thereof, a plurality of second elongated metal ribbons disposed substantially parallel to each other, each of said second ribbons having corrugations which include periodic nodes interconnected by ribbon sections, with the corrugations of said second ribbons having the same phase, pitch and amplitude, and the same height measured between opposite edges thereof, the height of said second ribbons being equal to the height of said first ribbons, said first and second ribbons being secured at said opposite edges thereof to said faces with the planes of said ribbons being generally perpendicular to said faces, the ratio of said pitch of said first ribbons to said pitch of said second ribbons being an integer greater than one and of relatively low value, the ratio of said amplitude of said first ribbons to said amplitude of said second ribbons being greater than one and of relatively low value, and said first ribbons being alternated and interleaved and in phase with said second ribbons, with said alternated and interleaved first and second ribbons being joined to each other only at nodes thereof, providing a plurality of identical cells of generally triangular configuration having their axes perpendicular to said faces.

Claim 5

The structural member of claim 2 wherein said amplitude ratio is approximately 2.5 and said pitch ratio is an integer in the range of 3.

Claim 6

The structural member of claim 3 wherein said ribbon nodes of said first and second ribbons and the ribbon sections intermediate said nodes of said first and second ribbons are flat rectangular surfaces, with said rectangular sections of sAid first and second ribbons larger than said rectangular nodes of said first and second ribbons.

Claim 7

A structural member of the type having a metal cellular core sandwiched between two parallel metal skin sheets, comprising: a pair of faces of metal sheet material, dissimilar sets of first and second elongated interleaved equal height corrugated metal ribbons running parallel to each other, said first and second ribbons being joined at opposite edges thereof to said faces, the planes of said first and second ribbons being generally perpendicular to said faces, said first and second ribbons having periodically occurring nodes defining first and second corrugation pitches which differ by an integral multiple, said first and second ribbons being joined to each other only at nodes, and said first and second ribbons also having respectively different amplitudes with the amplitude of the lesser pitch ribbons less than the amplitude of the greater pitch ribbons, said alternated and interleaved first and second joined corrugated ribbons forming a plurality of generally triangular-shaped cells, all of which are identical and oriented with the axes of said cells perpendicular to said faces.

Claim 8

A structural member of the type having a metal cellular core sandwiched between two parallel metal skin sheets, comprising: a pair of faces of metal sheet material, dissimilar sets of first and second elongated interleaved equal height corrugated metal ribbons running parallel to each other, said first and second ribbons being joined at opposite edges thereof to said faces, the planes of said first and second ribbons being generally perpendicular to said faces, said first and second ribbons having periodically occurring nodes defining first and second corrugation pitches which differ by an integral multiple, said first and second ribbons being joined to each other only at nodes, and said first and second ribbons also having respectively different amplitudes with the amplitude of the lesser pitch ribbons less than the amplitude of the greater pitch ribbons, said alternated and interleaved first and second joined corrugated ribbons forming a plurality of generally triangular-shaped cells, all of which are identical and oriented with the axes of said cells perpendicular to said faces.

Claim 9

The structural member of claim 5 wherein said nodes of said first and second ribbons and the ribbon sections intermediate said nodes of said first and second sections are flat rectangular surfaces, with said intermediate rectangular ribbon sections of said first and second ribbons larger than said rectangular nodes of said first and second ribbons.

Claim 10

A structural member of the type having sandwiched between two parallel metal skin sheets a metal cellular core plane structure characterized by a high degree of formability, comprising: a plurality of first elongated metal ribbons, disposed substantially parallel to each other with their respective edges aligned, said first ribbons each being corrugated to include periodic nodes interconnected by ribbon sections, with the corrugations of each first ribbon having the same phase, pitch and amplitude, a plurality of second elongated metal ribbons, disposed substantially parallel to each other with their respective edges aligned with each other and to said edges of said first ribbons, each of said second ribbons being corrugated to include periodic nodes interconnected by ribbon sections with the corrugations having the same phase, pitch and amplitude, said first and second ribbons having equal height, the ratio of said pitch of said first ribbons to said pitch of said second ribbons being an integer greater than one and of relatively low value, the ratio of said amplitude of said first ribbons to said amplitude of said second ribbons being greater than one and of relatively low value, said first ribbons being alternated and interleaved and in phase with said second ribbons, with said first and second alternated and interleaved ribbons being joined to each other only at nodes thereof to form a core having identical generally triangular cells, the widths of said first and second ribbons being defined as the ribbon dimension transverse of the elongated ribbon direction, said widths being less than said elongated ribbon direction, and said widths being less than the combined amplitudes of said first and second ribbons, whereby said widths of said first and second ribbons define the thickness of said cellular core, and the lengths of said ribbons in said elongated ribbon direction and said combined amplitudes define the dimensions of said cellular core, and a pair of metal sheets secured to the opposite edges of said first and second ribbons whereby the axes of the core cells extend perpendicularly to the plane of said sheets.

Claim 11

A structural member of the type having sandwiched between two parallel metal skin sheets a metal cellular core plane structure characterized by a high degree of formability, comprising: a plurality of first elongated metal ribbons, disposed substantially parallel to each other with their respective edges aligned, said first ribbons each being corrugated to include periodic nodes interconnected by ribbon sections, with the corrugations of each first ribbon having the same phase, pitch and amplitude, a plurality of second elongated metal ribbons, disposed substantially parallel to each other with their respective edges aligned with each other and to said edges of said first ribbons, each of said second ribbons being corrugated to include periodic nodes interconnected by ribbon sections with the corrugations having the same phase, pitch and amplitude, said first and second ribbons having equal height, the ratio of said pitch of said first ribbons to said pitch of said second ribbons being an integer greater than one and of relatively low value, the ratio of said amplitude of said first ribbons to said amplitude of said second ribbons being greater than one and of relatively low value, said first ribbons being alternated and interleaved and in phase with said second ribbons, with said first and second alternated and interleaved ribbons being joined to each other only at nodes thereof to form a core having identical generally triangular cells, the widths of said first and second ribbons being defined as the ribbon dimension transverse of the elongated ribbon direction, said widths being less than said elongated ribbon direction, and said widths being less than the combined amplitudes of said first and second ribbons, whereby said widths of said first and second ribbons define the thickness of said cellular core, and the lengths of said ribbons in said elongated ribbon direction and said combined amplitudes define the dimensions of said cellular core, and a pair of metal sheets secured to the opposite edges of said first and second ribbons whereby the axes of the core cells extend perpendicularly to the plane of said sheets.

Claim 12

The structural member of claim 7 wherein said amplitude ratio is approximately 2.5 and said pitch ratio is an integer in the range of 3.

Claim 13

The structural member of claim 8 wherein said nodes of said first and second ribbons and the ribbon sectioNs intermediate said nodes of said first and second ribbons are flat rectangular surfaces, with said intermediate rectangular ribbon sections of said first and second ribbons larger than said rectangular nodes of said first and second ribbons.

Claim 14

A structural member of the type in which a metal cellular core plane structure is sandwiched between metal skin sheets, comprising: dissimilar sets of first and second elongated interleaved equal height metal corrugated ribbons running parallel to each other, said first and second ribbons having periodically occurring nodes defining first and second corrugation pitches which differ by an integral multiple, said first and second ribbons being joined only at nodes, and said first and second ribbons also having respectively different first and second amplitudes with the amplitude of the lesser pitch ribbons less than the amplitude of the greater pitch ribbons, the widths of said first and second ribbons being defined as the ribbon dimension transverse of the elongated ribbon direction, said widths of said first and second ribbons being less than said elongated ribbon direction, and said widths of said first and second ribbons being less than the combined amplitudes of the plurality of first and second ribbons, a pair of metal skins secured to the edges of said first and second ribbons on opposite sides thereof to orient the axes of said cells perpendicular to said skins, said widths of said first and second ribbons define the thickness of said cellular core, and the lengths of said first and second ribbons in each elongated ribbon direction and said combined amplitudes of the plurality of said first and second ribbons define the dimensions of the plane of said cellular core, said cellular including a plurality of cells which are identical and of generally triangular cell configuration with the axes of said cells perpendicular to said skins.

Claim 15

A structural member of the type in which a metal cellular core plane structure is sandwiched between metal skin sheets, comprising: dissimilar sets of first and second elongated interleaved equal height metal corrugated ribbons running parallel to each other, said first and second ribbons having periodically occurring nodes defining first and second corrugation pitches which differ by an integral multiple, said first and second ribbons being joined only at nodes, and said first and second ribbons also having respectively different first and second amplitudes with the amplitude of the lesser pitch ribbons less than the amplitude of the greater pitch ribbons, the widths of said first and second ribbons being defined as the ribbon dimension transverse of the elongated ribbon direction, said widths of said first and second ribbons being less than said elongated ribbon direction, and said widths of said first and second ribbons being less than the combined amplitudes of the plurality of first and second ribbons, a pair of metal skins secured to the edges of said first and second ribbons on opposite sides thereof to orient the axes of said cells perpendicular to said skins, said widths of said first and second ribbons define the thickness of said cellular core, and the lengths of said first and second ribbons in each elongated ribbon direction and said combined amplitudes of the plurality of said first and second ribbons define the dimensions of the plane of said cellular core, said cellular including a plurality of cells which are identical and of generally triangular cell configuration with the axes of said cells perpendicular to said skins.

Claim 16

The structural member of claim 10 wherein said first and second ribbons have a pitch ratio equal to an integer in the approximate range of three, and have an amplitude ratio equal to approximately 2.5.

Claim 17

The structural member of claim 11 wherein said ribbon nodes of said first and second ribbons and the ribbon sections intermediate said nodes of said first and second ribbons are flat rectangular surfaces, with said intermediate rectangular ribbon sections of said first and second ribbons larger than said rectangular nodes of said first and second ribbons.