IPC 6 English version  Class F27
SECTION F– MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

F 27

FURNACES; KILNS; OVENS; RETORTS (specially adapted for a purpose covered by a single other class and specifically mentioned in that class, see the class in question, e.g. bakery ovens A 21 B, glass melting furnaces C 03 B, coke or gas-making apparatus C 10 B, C 10 J, apparatus for cracking hydrocarbons C 10 G, blast furnaces C 21 B, converters for making steel C 21 C, furnaces for heat treatment of metal C 21 D; furnaces for electroslag or arc remelting of metals C 22 B 9/00; enamelling ovens C 23 D; combustion apparatus F 23; electric heating H 05 B) [4]

Notes

(1)

This class covers:

furnaces, kilns, ovens, retorts, open sintering apparatus, and details or accessories therefor, in general;

the arrangement of electrical heating elements in or on furnaces.

(2)

This class does not cover:

electrical heating elements per se;

processes carried on within the furnaces.

(3)

In this class, the following term is used with the meaning indicated:

"furnaces" covers kilns, ovens, or retorts.

F 27 B

FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS

F 27 D

DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE (combustion apparatus F 23)

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