Patent ID: 7674343

Claim:
A method of manufacturing double glazing having glass plates, a spacer disposed between peripheries of the glass plates, and an airtightly sealed air space surrounded by the spacer between the glass plates, the method using a spacer forming device including an applicator head for applying a spacer forming material, and spacer forming material supply means having an extruding means that extrudes the spacer forming material while melting and mixing the material and a fixed displacement pump for supplying the spacer forming material extruded from the extruding means to the applicator head, wherein, at a tip end of a pump housing of the fixed displacement pump, a pipe is connected to the extruding means and at a rear part of an outer surface of the pump housing, a pipe is connected to the applicator head and further, an extrusion rod is provided in a pump chamber of the pump housing which is slidably inserted from a top portion of the pump housing opposite to the tip end of the pump housing, the method comprising the steps of: feeding the spacer forming material to the pump chamber such that the extrusion rod is moved backward by extrusion pressure of the spacer forming material extruded from the extruding means; supplying the spacer forming material fed into the pump chamber to the applicator head by the extrusion rod being moved forward, which causes all of the spacer forming material displaced by the extrusion rod and supplied to the applicator head to pass through between the inner peripheral surface of the pump housing and the outer peripheral surface of the extrusion rod; applying the spacer forming material from the applicator head along the periphery of an upper surface of one of the glass plates thereon to form the spacer; and attaching by press the other one of the glass plates to the spacer.