Heating furnace

Patent metadata

Field	Value
Publication number	US-11085698-B2
Application number	US-201916290027-A
Country	US
Kind code	B2
Filing date	Mar 1, 2019
Priority date	Mar 28, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A heating furnace comprising a furnace body; an accommodation space in the furnace body, the accommodation space accommodating a work; an exhaust port; and a heat insulator provided between the accommodation space and the exhaust port, the heat insulator including a pillar-shaped honeycomb structure including ceramic partition walls sectioning a plurality of cells extending from one bottom to another bottom.

First claim

The invention claimed is:

1. A heating furnace comprising:
a furnace body;
an accommodation space in the furnace body, the accommodation space is adapted for accommodating a work;
an exhaust port comprising an opening in the furnace body; and
a heat insulator provided between the accommodation space and the opening of the exhaust port, the heat insulator including a pillar-shaped honeycomb structure including ceramic partition walls sectioning a plurality of cells extending from one bottom to another bottom, wherein
a kiln tool having vertically arranged one or ore shelf boards on which a work is to be placed is installed in the accommodation space, and
the exhaust port is provided below a lowermost shelf board.

2. The heating furnace according to claim 1 , wherein the porosity of the partition wall of the pillar-shaped honeycomb structure is greater than or equal to 13%.

3. The heating furnace according to claim 1 , wherein the thermal conductivity of the pillar-shaped honeycomb structure at 20° C. is less than or equal to 300 W/(m K).

4. The heating furnace according to claim 1 , wherein a softening point of the pillar-shaped honeycomb structure is greater than or equal to 1200° C.

5. The heating furnace according to claim 1 , wherein an angle between a direction of gravity and a direction in which at least part of the plurality of cells included in the pillar-shaped honeycomb structure extends is 0° to 30°.

6. The heating furnace according to claim 5 , wherein an apparent aperture ratio of the pillar-shaped honeycomb structure is less than or equal to 94%.

7. The heating furnace according to claim 1 , wherein an angle between a direction of gravity and a direction in which at least part of the plurality of cells included in the pillar-shaped honeycomb structure extends is 60° to 90°.

8. The heating furnace according to claim 1 , wherein the lowermost shelf board includes the heat insulator.

9. The heating furnace according to claim 8 , wherein when an arbitrary cross section of the heat insulator, constituting the lowermost shelf board, parallel to a placement surface of the lowermost shelf board is vertically projected onto the placement surface, a proportion of an overlapping area between a projected figure of the cross section and the placement surface to an area of the placement surface of the lowermost shelf board is greater than or equal to 40%.

10. The heating furnace according to claim 8 , wherein the lowermost shelf board has a laminate structure in which the heat insulator is sandwiched between upper and lower support plates.

Assignees

• Ngk Insulators Ltd

Inventors

• Nakamura Tomoo

Classifications

• F27B17/0016 Primary

  Chamber type furnaces · CPC title

• F27D3/12

  Travelling or movable supports or containers for the charge · CPC title

• F27D5/0018

  Separating elements · CPC title

• F27B9/36

  Arrangements of heating devices · CPC title

• F27B11/00

  Bell-type furnaces · CPC title