Manual of U.S. Patent Classification
as of June 30, 2000

Class
373
INDUSTRIAL ELECTRIC HEATING FURNACES

Class definitions may be accessed by clicking on the class title, above.
Subclass definitions may be accessed by clicking on the subclass number, below.

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Subclass		Title
ClassTitle		===> INDUSTRIAL ELECTRIC HEATING FURNACES
1		PLURAL DIVERSE HEATING MEANS
2		. Arc
3		. . With resistance
4		. . With induction
5		. Resistance
6		. . With induction
7		. Induction
8		ENVIRONMENTAL CONTROL
9		. Arc furnace
10		ELECTRON BEAM FURNACE DEVICE
11		. Vaporizing furnace
12		. . Power supply and control circuit
13		. . Gun assembly
14		. . . With deflection control
15		. Ingot remelting
16		. With plural beam devices
17		. Zone melting
18		PLASMA FURNACE DEVICE
19		. Indirect heating
20		. . Rotary furnace
21		. Remelting furnace (i.e., ingot remelting)
22		. Direct furnace (i.e., plasma flame impinges on the melt)
23		. . Expanded arc column
24		. . Sidewall mounted plasmatron
25		. . Control system
26		GLOW DISCHARGE FURNACE DEVICE
27		GLASS FURNACE DEVICE
28		. Filament discharge (i.e., bushing)
29		. Joule effect heating
30		. . Furnace body detail
31		. . . Multi-chamber
32		. . . . With heating between chambers
33		. . Charging or discharging
34		. . . Including batch pre-heating
35		. . . Including discharge area heating
36		. . Electrode assembly
37		. . . Protection means
38		. . . Holder
39		. . Electrical system
40		. . . Regulation
41		. . . Electrode arrangement (e.g., array)
42		ELECTROSLAG REMELTING DEVICE
43		. Plural furnace units
44		. Body detail
45		. . Crucible
46		. Start-up
47		. Power supply system
48		. . Conductor arrangement
49		. . Control
50		. . . By changing electrode position
51		. Electrode replacement
52		. Electrode support
53		. . Plural electrodes
54		. Electrode
55		. . With protective shield
56		WITH CONDENSATING DEVICE
57		. Including resistance furnace detail
58		. . With open circuit (i.e., charge internal resistance heating)
59		. Including induction furnace detail
60		ARC FURNACE DEVICE
61		. Indirect
62		. . Arc between spaced electrodes
63		. . . Charge fed into space
64		. . . With arc deflection means
65		. . Arc between electrode and crucible exterior
66		. . Combined with or convertible to direct arc furnace
67		. Ingot remelting
68		. . With internal atmosphere control (e.g., pressure, vacuum, etc.)
69		. . With electrode holder or guide
70		. . With power regulation
71		. Furnace body detail
72		. . Hearth or crucible
73		. . Roof
74		. . . With cooling
75		. . Sidewall
76		. . . With cooling
77		. . With internal atmosphere control (e.g., pressure, vacuum, etc.)
78		. Plural furnace units
79		. Charging or discharging
80		. . With charge pre-heating
81		. . Top charging
82		. . . Through electrode
83		. . Bottom pour
84		. . Discharge by tilting
85		. For manipulation of the charge or melt (e.g., stirring)
86		. . Mechanical
87		. . Crust breaking device
88		. Electrode
89		. . Self-baking (i.e., Soderberg)
90		. . Non-consumable
91		. . Sectional
92		. . . With means to join sections
93		. . Composite (e.g., water cooled body with carbon tip)
94		. Electrode support
95		. . Seal
96		. . With electrode shield
97		. . For Soderberg electrode (e.g., casing)
98		. . Mast
99		. . . Crosshead
100		. . Slipping holder
101		. . With electrical contact or terminal
102		. Power supply system
103		. . Cable or cable suspension arrangement
104		. . With power regulation
105		. . . By changing arc length
106		. . . . Using a hydraulic or pneumatic device
107		. . With magnetically influenced arc
108		. . D.C. power
109		RESISTANCE FURNACE DEVICE
110		. With internal atmosphere control (e.g., pressure, vacuum, etc.)
111		. . Having tubular charge containing or supporting element
112		. . Vacuum
113		. For cooling
114		. . Terminal
115		. Charging or discharging
116		. For manipulation of the charge or melt (e.g., stirring)
117		. With heating element detail
118		. . Resistance crucible
119		. . Wall contained
120		. . Open circuit (e.g., charge internal resistance heating)
121		. . . Salt bath heating
122		. . . Including crucible or hearth structure details
123		. . . With preheating
124		. . . . Including starting resistor
125		. . . Including terminal detail
126		. . . . With axial bore
127		. . Having resistance encasement means
128		. . Mounting
129		. . . Base
130		. . . Side wall
131		. . . . With resistor element compression
132		. . Non-metallic resistor
133		. . . Rod-like
134		. . Including resistor shape detail
135		. Control
136		. . Temperature
137		. Lining
138		INDUCTION FURNACE DEVICE
139		. Zone melting
140		. With internal atmosphere control (e.g., pressure, vacuum, etc.)
141		. . Vacuum
142		. For charging or discharging
143		. . By tilting
144		. Having plural heating elements
145		. Having condition signaling means
146		. With means for manipulation of the charge or melt (e.g., stirring)
147		. Power supply system
148		. . Regulating
149		. For furnace regulating
150		. . Electrical
151		. Coreless
152		. . Coil
153		. . . Support
154		. . . Cooling
155		. . Lining
156		. . Crucible
157		. . . Conducting (e.g., graphite)
158		. . Cooling
159		. Core-type (i.e., channel)
160		. . Coil
161		. . Channel
162		. . . Lining
163		. . Crucible or hearth
164		. . Lining
165		. . Cooling
166		MISCELLANEOUS

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Last Modified: 6 October 2000