| 摘要 |
<p>PURPOSE: To ensure structural strength while enhancing the heat insulating performance by making an evacuation opening for injecting foam into a space defined by inner and outer plates and covering the opening with an elastic sealing material. CONSTITUTION: A heat insulator comprises inner and outer plates 3, 2 defining a space being filled with a ventilating foamed body 8 of an open cell foamable material. The outer plate 2 is previously provided with an opening 9 sealed with an elastic sealing material 10, e.g. silicon rubber. In order to discharge gas contained in the foamed body 8 within the heat insulator 7, a hypodermic syringe connected with a vacuum pump is pulled out of the sealing material 10 and the resin layer of the foamed body 8, i.e., the skin 11, into the foamed body 8 and the inner gas is discharged thus reducing the pressure to a specified level. When the needle is drawn out, the hole made in the skin 11 is closed by the elasticity of the sealing material 10 and vacuum is sustained in the heat insulator. Since the foamed body 8 is filled while touching inner and outer plates 3, 2 tightly, structural strength can be ensured.</p> |
