Title:
METHOD FOR MOLDING FOAMED SYNTHETIC RESIN MOLDING
Document Type and Number:
Japanese Patent JP3680906
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To improve the molding efficiency of a foamed molding and to reduce equipment and production costs by supplying a material for a foamed synthetic resin molding into a cavity space which controls pressure under the atmospheric pressure, reducing the pressure after a mold being closed and before the material being packed, and restoring the pressure of the cavity to the atmospheric pressure after the gelling of the material and before demolding.
SOLUTION: Before the setting of an upper mold 3 and a lower mold 2, a soft polyurethane foam molding material is introduced into the lower mold 2, the upper and lower molds 3, 2 are set, a suction valve 26 is opened and an exhaust valve 24 is opened before the molding material being packed, and a vacuum pump 28 is actuated. The pressure of chamber 8 and a cavity space 4 through a fine clearance S, which is detected by a pressure sensor 30, is reduced to a prescribed pressure, and a control part 29 the pump 28, the valve 24, and an air supply valve 26. The molding material is packed under reduced pressure and gelled, at the end of the gelation, the pressure of the cavity 4 is restored to the atmospheric pressure, and the molding is demolded. A low density foamed resin of high expansion ratio is formed with good molding efficiency, reducing equipment and production costs.
Inventors:
Teruo Iwai
Yutaka Hirata
Yutaka Hirata
Application Number:
JP5276198A
Publication Date:
August 10, 2005
Filing Date:
February 18, 1998
Export Citation:
Assignee:
Bridgestone Corporation
International Classes:
B29C39/42; B29C39/02; B29K75/00; B29K105/04; B29L31/58; (IPC1-7): B29C39/02; B29C39/42
Domestic Patent References:
| JP55014297A | ||||
| JP10034678A | ||||
| JP2223407A |
Attorney, Agent or Firm:
Takashi Kojima
Yuko Nishikawa
Yuko Nishikawa