Alternative core material based vacuum insulated panels

Patent metadata

Field	Value
Publication number	US-2017227165-A1
Application number	US-201615040413-A
Country	US
Kind code	A1
Filing date	Feb 10, 2016
Priority date	Feb 10, 2016
Publication date	Aug 10, 2017
Grant date	—

Abstract

A vacuum insulated panel (VIP) and a method of manufacturing a VIP includes a rigid core material having high insulation and low conductivity properties. The rigid core may be made of an inorganic material that effectively mimics a porous silica core material. The core material includes large particles of an inorganic material having a diameter in a range of 10 μm to 50 μm. A portion of these large particles may be ground into small particles having a diameter of less than 1 μm. The small particles are mixed with a portion of the large particles to form a core material which is then mixed with a fiber skeleton and compacted under vacuum along with a fibrous skeleton for structure. The resulting structure provides a porosity ranging from 10 nm to 1 μm in diameter.

First claim

What is claimed is:

1 . A vacuum insulated panel comprising:
a core having a porosity in a range of approximately 10 nm to approximately 1 μm, wherein the core comprises: a plurality of large particles of an inorganic material with a diameter in a range of approximately 10 μm to approximately 50 μm; a plurality of small particles of the inorganic material with a diameter in a range of approximately 0.01 μm to approximately 10 μm, at least some of the small particles attached to at least some of the large particles; a fiber skeleton intermixed with the large and small particles; and an envelope having a cavity, wherein the core is disposed within the cavity and vacuum compacted.

2 . The vacuum insulated panel of claim 1 , wherein the inorganic material is at least one of (a)-(g); (a) perlite, (b) pumice, (c) natural gypsum, (d) calcium sulfate hemi hydrate, (e) anhydrite calcium sulfate, (f) calcium sulfate di-hydrate, and (g) wollastonite.

3 . The vacuum insulated panel of claim 1 , wherein the fiber skeleton is at least one of (a)-(e): (a) mineral fiber, (b) high density glass fiber, (c) mineral oxide fiber, (d) loose microfiber, and (e) woven fiber.

4 . The vacuum insulated panel of claim 1 , wherein each of the plurality of small particles has a diameter in a range of approximately 0.01 μm to approximately 1 μm.

5 . The vacuum insulated panel of claim 1 , wherein the envelope is a metallic coated polymer.

6 . The vacuum insulated panel of claim 1 , wherein each of the plurality of large particles is at least partially covered by a portion of the plurality of small particles.

7 . The vacuum insulated panel of claim 1 , wherein the core has a core material to fiber skeleton ratio of at least 1:1.

8 . The vacuum insulated panel of claim 1 , wherein the core consists of the large particles, small particles, and the fiber skeleton.

9 . A vacuum insulated panel comprising:
a pair of barrier walls; a core sandwiched between the pair of barrier walls, the core including a core material and a fiber skeleton; wherein the core material is an inorganic material and includes a first class of particles with a diameter in a range of approximately 10 μm to approximately 50 μm and a second class of particles with a diameter in a range of approximately 0.01 μm to approximately 10 μm; wherein the fiber skeleton is mixed with the core material forming a porous structure; and wherein the porous structure includes a plurality of the first class of particles mixed with a plurality of the second class of particles, wherein each of the plurality of first class particles is at least partially covered by a portion of the plurality of second class particles.

10 . The vacuum insulated panel of claim 9 , wherein the porous structure has a porosity in a range of approximately 10 nm to approximately 1 μm when compacted under vacuum.

11 . The vacuum insulated panel of claim 9 , wherein the inorganic material is at least one of (a)-(g); (a) perlite, (b) pumice, (c) natural gypsum, (d) calcium sulfate hemi hydrate, (e) anhydrite calcium sulfate, (f) calcium sulfate di-hydrate, and (g) wollastonite.

12 . The vacuum insulated panel of claim 9 , wherein the fiber skeleton is at least one of (a)-(e); (a) mineral fiber, (b) high density glass fiber, (c) mineral oxide fiber, (d) loose microfiber, and (e) woven fiber.

13 . The vacuum insulated panel of claim 1 , wherein the pair of barrier walls is metallic coated polymer.

14 . The vacuum insulated panel of claim 1 , wherein the porous structure includes a core material to fiber skeleton ratio of at least 1:1.

15 . The vacuum insulated panel of claim 1 , wherein each of the small particles has a diameter in a range of approximately 0.01 μm to approximately 1 μm.

16 . The vacuum insulated panel of claim 1 , wherein the core consists of the large particles, small particles, and the fiber skeleton.

17 . A method of manufacturing a vacuum insulated panel, the method comprising:
dividing a plurality of large particles of an inorganic material into a first portion and a second portion, wherein each of the large particles has a diameter in a range of approximately 10 μm to approximately 50 μm; grinding the first portion of large particles into a plurality of small particles, wherein each of the plurality of small particles has a diameter of less than 1 μm; mixing the plurality of small particles of the first portion with the plurality of large particles of the second portion to create a core material; mixing a fiber skeleton with the core material to create a core mixture; inserting the core mixture into a cavity of an envelope; and compacting the core mixture within the envelop under vacuum.

18 . The method of claim 17 , wherein grinding the first portion includes grinding the plurality of large particles of the first portion into small particles with a diameter in a range of approximately 0.01 μm to approximately 1 μm.

19 . The method of claim 18 , wherein compacting the core mixture includes forming a porous structure having a porosity in a range of approximately 10 nm to approximately 1 μm.

20 . The method of any one of claim 17 , wherein mixing the fiber skeleton with the core material includes mixing a first mass of the core material with a second mass of the fiber skeleton, the first mass being at least equal to the second mass.

Assignees

• United States Gypsum Co

Inventors

• Ray Suman Sinha
• Rao Ajith

Classifications

• E04C2/44

  characterised by the purpose · CPC title

• B29C70/88

  characterised primarily by possessing specific properties, e.g. electrically conductive or locally reinforced · CPC title

• B29K2105/251

  Particles, powder or granules (expandable particles B29K2105/046) · CPC title

• E04C2/30

  characterised by the shape or structure (translucent E04C2/54) · CPC title

• F17C3/08 Primary

  by vacuum spaces, e.g. Dewar flask (for household use A47J41/02) · CPC title