|  | F |
SECTION F — MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

|  | F01 - F04 |
Subsection index
MACHINES |
positive displacement |
rotary or oscillating piston |
liquid and elastic fluid or elastic fluid | F01C
liquid only | F04C
reciprocating piston or other |
liquid and elastic fluid or elastic fluid | F01B
liquid only | F04B
non-positive displacement |
liquid and elastic fluid or elastic fluid | F01D
liquid only | F03B
ENGINES |
positive displacement |
rotary or oscillating piston |
liquid and elastic fluid or elastic fluid | F01C
liquid only | F03C
reciprocating piston or other |
liquid and elastic fluid or elastic fluid | F01B
liquid only | F03C
non-positive displacement |
liquid and elastic fluid or elastic fluid | F01D
liquid only | F03B
PUMPS |
positive displacement |
rotary or oscillating piston | F04C
reciprocating piston or other | F04B
non-positive displacement | F04D

LIGHTING; HEATING

|  | F27 |
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 Fulltext... Hierarchy... Expanded...A21B, glass melting furnaces Fulltext... Hierarchy... Expanded...C03B, coke or gas-making apparatus Fulltext... Hierarchy... Expanded...C10B, Fulltext... Hierarchy... Expanded...C10J, apparatus for cracking hydrocarbons Fulltext... Hierarchy... Expanded...C10G, blast furnaces Fulltext... Hierarchy... Expanded...C21B, converters for making steel Fulltext... Hierarchy... Expanded...C21C, furnaces for heat treatment of metal Fulltext... Hierarchy... Expanded...C21D; furnaces for electroslag or arc remelting of metals Fulltext... Hierarchy... Expanded...C22B 9/00; enamelling ovens Fulltext... Hierarchy... Expanded...C23D; combustion apparatus Fulltext... Hierarchy... Expanded...F23; electric heating Fulltext... Hierarchy... Expanded...H05B) [4]

|  | F27 |
Note(s) This class covers: furnaces, kilns, ovens, retorts, open sintering apparatus and other similar apparatus for heat treatment of materials or articles, and details or accessories therefor, in general; the arrangement of electrical heating elements in or on furnaces. This class does not cover: combustion apparatus per se, i.e. apparatus for direct combination of oxygen gas and a burnable substance; [7] electrical heating elements per se; processes carried on within the furnaces. In this class, the following term is used with the meaning indicated: "furnaces" covers kilns, ovens, or retorts.

|  | F27B |
FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS

|  | F27B |
Note(s) Attention is drawn to the references and Notes following the title of class Fulltext... Hierarchy... Expanded...F27 and the Note (3) of section H.

|  | F27B |
Subclass index
FURNACES WITH STATIONARY CHARGE |
Shaft furnaces | 1/00
Horizontal furnaces | 3/00, 5/00
Bell-type furnaces | 11/00
With progression of heating | 13/00
Crucible furnaces, tank furnaces | 14/00
STATIONARY FURNACES WITH MECHANICALLY-MOVED CHARGE | 9/00
ROTARY FURNACES | 7/00, 13/00
OTHER FURNACES; COMBINATIONS | 15/00, 17/00; 19/00
OPEN SINTERING OR LIKE APPARATUS | 21/00

|  | F27D |
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 Fulltext... Hierarchy... Expanded...F23)

|  | F27D |
Note(s) Attention is drawn to the references and Notes following the title of class Fulltext... Hierarchy... Expanded...F27 and Note (3) of section H.

|  | F27D |
Subclass index
CONSTRUCTIONAL FEATURES | 1/00
HANDLING AND SUPPORTING CHARGE | 3/00, 5/00, 15/00
PREHEATING CHARGE; COOLING; USING WASTE HEAT OR GASES | 13/00; 9/00, 15/02; 17/00
ARRANGEMENTS OF ELECTRIC HEATING ELEMENTS | 11/00
ARRANGEMENTS OF CONTROL AND SAFETY DEVICES | 19/00, 21/00
OTHER FEATURES; OTHER DETAILS | 7/00; 23/00