Method of manufacture of hollow reinforced plastic articles

• US 3,205,288 A
• Filed: 07/24/1961
• Issued: 09/07/1965
• Est. Priority Date: 07/24/1961
• Status: Expired due to Term

• Current Assignee: Curtiss-Wright Flight Systems Incorporated Fairfield NJ 07006 A Corporation O de
• Original Assignee: William E. Bates
• Inventors: Bates, William E.
• Application Number:
  US04/126,117
• Time in Patent Office: 1,506 Days
• US Class Current: 264/255
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 33/54 made of powdered or granular material
• CPC Class Codes: B29C 43/12 using bags surrounding the moulding material or using membranes contacting the moulding material
• CPC Class Codes: B29C 70/34 and shaping or impregnating by compression , i.e. combined with compressing after the lay-up operation
• CPC Class Codes: B29C 70/44 using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
• CPC Class Codes: B29C 70/446 Moulding structures having an axis of symmetry or at least one channel, e.g. tubular structures, frames
• CPC Class Codes: B29C 70/46 using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
• CPC Class Codes: B29C 70/86 Incorporated in coherent impregnated reinforcing layers, e.g. by winding
• CPC Class Codes: B29C 70/865 completely encapsulated
• CPC Class Codes: B29D 99/0028 hollow blades
• CPC Class Codes: B29K 2711/14 Wood, e.g. woodboard or fibreboard

Claims

1. A METHOD OF MAKING A HOLLOW PROPELLER BLADE COMPRISING THE STEPS OF PROVIDING A PAIR OF COMPOSITE SHEETS EACH CONSISTING OF A LAYER FORMED OF RESIN IMPREGNATED REINFORCING GLASS CLOTH ON ONE SIDE OF A THICKER LAYER OF LESS DENSE MATERIAL, HEATING SAID COMPOSITE SHEETS, APPLYING RESIN IMPREGNATED GLASS CLOTH TO THE OTHER SIDE OF THE THICKER LAYER OF EACH OF THE COMPOSITE SHEETS BEFORE SUCH SHEETS HAVE COOLED SUBSTANTIALLY, PERFORMING THE RESULTING MULTILAYERED SHEETS ON OPPOSITE SIDES OF AN EXPANDABLE AND CONTRACTABLE MANDREL IN A MOLD TO SUBSTANTIALLY THE CONFIGURATION OF THE PROPELLER BLADE, CURING THE PERFORMED SHEETS UNDER HEAT AND PRESSURE IN THE MOLD, REMOVING THE PERFORMED SHEETS FROM THE MANDREL, APPLYING RESIN IMPREGNATED REINFORCING GLASS CLOTH TO THE OPPOSITE SIDES AND OVER EDGES OF THE MANDREL, REPLACING THE PERFORMED SHEETS ON THE MANDREL, APPLYING ADDITIONAL RESIN IMPREGNATED REINFORCING GLASS CLOTH TO THE OPPOSITE SIDES OF THE MANDREL AND OVER THE PERFORMED SHEET AS WELL AS OVER EDGES OF THE MANDREL, EXPANDING THE MANDREL IN A MOLD HAVING THE DESIRED CONTOUR FOR THE PROPELLER BLADE, CURING THE MOLDED FORM THEREIN UNDER HEAT AND PRESSURE, AND COLLAPSING AND REMOVING THE MANDREL FROM THE FORMED PROPELLER BLADE.