Patent ID: 6132826
Filing Date: 2000-10-17
Classification: B29C,B29L,F04D,F05D,Y10T

Abstract:
A method of manufacturing a hollow blade whereby first and second resin-made blade bodies formed by injection molding are put together and are joined by welding by means of an ultrasonic welding device to form a hollow blade internally provided with a hollow part, comprising the steps of:injection-molding the first and second blade bodies, forming respective convex parts swelling from respective surfaces of the first and second blade bodies at positions contiguous with and opposed to each other when both the blade bodies are put together;placing a horn of the ultrasonic welding device at a position that the horn crosses both the convex parts to come into contact with the top surfaces of the convex parts while pressing them at the same time and then, in this state, operating the ultrasonic welding device; andwelding contact surfaces of the first and second blade bodies which extend in a direction approximately orthogonal to a direction of putting together both the blade bodies at their portions corresponding to a pressing direction of the horn, and concurrently deforming both the convex parts by melting under pressure through the horn to trickle melting resin of both the convex parts into a clearance between the first and second blade bodies so that both the blade bodies are welded, thereby joining both the blade bodies into one piece to form a hollow blade.