PTO Manual of Classification for US patents

PTO Manual of Classification for US patents

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363-131 121-55A 14-.5
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Class Number: 122
 Class Title: LIQUID HEATERS AND VAPORIZERS

Subclass  Subclass
Number    Title

  1 R     PLANTS
  2       .Garbage
  3       .Motor vehicle
  1 A     .Air heaters
  1 B     .Once through
  1 C     .Feed water heaters
  4 R     MISCELLANEOUS
  4 A     .Electric boiler
  4 C     .Water-cooled stoker
  4 D     .Catalyst
  5       GAS-PRODUCER
  5.51    AIR-INJECTED
  5.52    .Combustion gas and vapor contact
  6 R     INDUSTRIAL
  6.5     .Port
  6.6     .Tuyeres
  6.7     ..Forge
  7 R     .Waste heat
  7 A     ..Steel converter
  7 B     ..Additional burner
  7 C     ..Waste sulfite
  7 D     ..Carbon monoxide
  8       .Water firebox
  9       ..Water tube type
  6 A     .Water-cooled walls
  6 B     .Bosh plates
  6 C     .Skew arch coolers
  10      FOR FLUID FUEL BURNER
  11      ROTARY
  12      ROTATABLY SUPPORTED
  13.1    STAND BOILER
  13.2    .Electric
         .Fire tube and water tube
  16      ..Fluid fuel
         .Fire tube
  17      ..Fluid fuel
         .Water tube
         ..Below boiler
  18      ...Fluid fuel
         ..Casing
  19      ...Fluid fuel
  14      .Fluid fuel
  15      .Solid fuel
  20 R    SUBSIDIARY
  20 A    .Subsidiary-heater firebox
  20 B    .Subsidiary-heater offtake flue
  29      ANNULAR FIREBOX
  30      MAGAZINE
  *       INDIRECTLY HEATED
         .Separate fluid
  32      ..Surface
  33      ...Furnacee
  34      ...Separator
  31.1    INDIRECTLY HEATED SEPARATE INJECTED FLUID
  31.2    .Submerged flame
  35      ACCUMULATOR
  36      AUXILIARY STEAM HEATER
  37      COMPARTMENT
         .Auxiliary
  38      ..Draft regulator
  39      FILM
  40      FLASHER
  41      .Fluid fuel
  42      FIRE AND WATER TUBE
  43      .Fluid fuel
  44.1    FIRE TUBE
  44.2    .With baffle in flue
  49      .Horizontal and vertical
         .Horizontal or inclined
         ..Water firebox
  50      ...Flue
  51      .Horizontal
  52      ..Plural
  53      ...Water tube
         ..Central firebox
  54      ...Double outlet
  55      ..Cylinder
         ..Depending fire tube
  56      ...Rear of bridge wall
         ..Double water firebox
  57      ...Alternate smoke return
  58 R    ..Drop water firebox
  59      ...Circulation conduit
         ...Double
  60      ....Alternate smoke return
  61      ...Drop water baffle
  62      ...Front and rear water baffle
  63      ...Front water baffle
  64      ...Interposed combustion chamber
  65      ...Rear water baffle
  66      ...Water coking chamber
         ...Water grate
  67      ....Intermediate draft
  68      ...Water tube
         ....Feed heater
  69      .....Check-valved
  70      ....Feeding air
  71      ....Solid baffle
  58 FB   ...Fire box construction
  72      ..Projecting into firebox
  73      ...Drop water firebox
         ..Return and reverse
  74      ...Drop water firebox
  75      ..Return fire tube
  76      ...Drop water firebox
  77      ....Internal water tube
         ...Water firebox
  78      ....Flue
  79      ..Subjacent water arch
  80      ..Subjacent fluee
  81      ..Subjacent transverse fire tube
         ..Superjacent feed heater
  82      ...In communication
  83      ..Transverse diaphragm
         ..Two diameters
  84      ...Great diameter over firebox
  85      ...Small diameter over firebox
  86      ....Water firebox
  87      ..U-coupling
  88      ..Upper drum
         ..Water arch
  89      ...Rear of fire tube
  90      ..Water firebox
         ...Firebox water heater
  91      ....Trapped circuit
  92      ...Magazine
  93      ...Offset
  94.1    ....Water tube type
  95.1    ...Plural with common combustion chamber
  95.2    ....Multiboilers
  96      ...Superposed
         ...Water grate
  97      ....Downdraft
  98      ....Updraft
         ...Water tube
  99      ....Straddle
         ...Water tube type
  100     ....Interposed flue
  101     ..Water smoke box
         ..Water tube
         ...Horizontal
  102     ....Over bridge wall
  103     ...Rear of fire tube
         ...Rearwardly declined
  104     ....Over bridge wall
         ...Rearwardly inclined
  105     ....Over bridge wall
  106     ..Water wall
  107     ...Drop water firebox
  108     ...Subjacent water tube
  109     .Inclined
         .Transverse
  110     ..Horizontal boiler
  111     ..Vertical boiler
  112     ...Water firebox
  113     ..Water tube
  114     .Vertical
  116     ..Central fire dome
  117     ..Central magazine
         ..Circulation tube
  118     ...Internal
  119     ..Cylinder
  120     ..Offset firebox
  121     ..Return fire tube
  122     ...Water firebox
  123     ..Separate compartment
  124     ..Side magazine
  125     ..Top water chamberr
  126     ..Water firebox
  127     ...Annular
  128     ...Central magazine
         ..Water grate
  129     ...Downdraft
  130     ..Water tube
  131     ...Internal
  132     ...Radial loop
  133     ...Spur
  115     ..Fluid fuel
  134     .Volute
  46      .Magazine
         .Flue
  47      ..Horizontal
  48      ..Vertical
  45      .Fluid fuel
  135.1   FLUE
  135.2   .Alternative stack
  135.3   .Sinusoidal flue
  136 R   .Horizontal
  137     ..Plural
  138     ...Water tube
  139     ..Drop water firebox
  140.1   ..Internal water tube
  140.2   ...Having water tube in flue
         ...Longitudinal
  141     ....Drop water firebox
  142     ...Return fire tube
  143     ...Spur
  144     ...Subjacent firebox
  145     ...Transverse
  146     ....Drop water firebox
  147     ....Return fire tube
  148     ...Water firebox
  149     ..Return fire tube
  150     ...Rear water tube
         ...Water smoke box
  151     ....Separate
  152     ..Water grate in flue
  153     ..Water tube
  154     ...Over bridge wall
  136 C   ..Horizontal-corrugated or finned
  155.1   .Vertical
  155.2   ..With flue baffle
  155.3   ..Having exterior heating flue
  155.4   ..Having corrugated flue
  155.5   ..Having undulating flue
  157     ..Central magazine
  158     ...Water jacket
         ..Circulation tube
  159     ...Internal
  160     ..Concentric shell
  161     ...Fluid fuel
  162     ...Central magazine
  163     ..Exterior drum
  165     ..Internal water heater
  166.1   ..With internal water tube
  166.2   ...Loop-type tubee
  168     ...Central magazine
  169     ...Coil
  170     ....Header
  171     ...Contracted inlet
  172     ...Header
  173     ...Horizontal spur
  174     ...Internal fire tube
  175     ...Offset water firebox
  176     ...Transverse
  177     ....Fluid fuel
  178     ...Vertical aligned fire tube
  179     ....Fluid fuel
  180     ....Spur water tube
  181     ...Vertical spur
  167     ...Fluid fuel
  182.1   ..With return fire tube
  182.2   ...Having symmetrical arrangement of tubes
  182.3   ...Having tubes offset from firebox
         ..Spiral water conduit
  183     ...Fluid fuel
         ..Standpipe
         ...Water tube
  184     ....Annular firebox
  185     ....Loop
  186     ....Spur
  187     ..Transverse fire tube
  164     ..Insulated outlet flue
  156     ..Fluid fuel
  *       HORIZONTAL CYLINDER
  188     .Drop water baffle
         .Offset subjacent firebox
  189     ..Water roof
  190     ..Water tube
         .Subjacent fire tube
  191     ..Beyond bridge wall
  192     .Water bridge wall
  193     .Water firebox
  194     ..Water tube type
  195     .Water tube
         ..Feed heater
  196     ...Check-valved
  197     ..Lateral-longitudinal
  198     ..Lateral-vertical
  199     ...Firebox
  200     ..Over fuel grate
  201     ..Subjacent internal fire tube
  202     ..Trapped circuit
         ..Water grate
  203     ...Downdraft
  204     ...Intermediate draft
  205     ...Multiple series
  206     ...Solid and water bar
  207     ...Updraft
  *       PLATE
         .Zigzag conduit
  208     ..Fluid fuel
  209.1   SECTIONAL
  209.2   .Feeding airr
  213     .Plural firebox
         .Horizontal sections
  214     ..Superimposed
  215     ...Central connection
  216     ....Fluid fuel
  217     ....Water firebox
  218     ...Water firebox
  219     ....Central magazine
         ...Water tube
         ....Internal fire tube
  220     .....Water firebox
         .Vertical sections
  221     ..Annularly positioned
  222     ...Central magazine
  223     ..Longitudinally positioned
  224     ...Casing
  225 R   ..Transversely positioned
  226     ...Casing
  227     ....Divided section
  228     ...Divided section
  229     ...Water grate
  225 A   ...Water heater in flue
  225 B   ...Water heater in boiler
  225 F   ...Feeding air
  230     ..Two-section
  212.1   .With magazine
  212.2   ..With return or alternate flue
  211     .Fluid or solid fuel
  210     .Fluid fuel
  232     .Water grate
  231     .Accessories
  *       TANK
  233     .Horizontal
  234     .Vertical
  235.11  WATER TUBE
  235.12  .Wall structure
  235.13  .With fuel burners having posts and tuyeres
  235.14  .Tube structure
  235.15  .Headers and connections
  235.16  .For plural fluids
  235.17  .Having baffles
  235.18  .Having seals
  235.19  .D-type tube
  235.21  ..Multiple D-type tubes
  235.22  .Wall loop
  235.23  .Having specific tube patterns
  235.24  .Screens
  235.25  ..Floor screens
  235.26  .Having slag and ash disposal
  235.27  .Locomotive-type
  235.28  .Having rotary flame
  235.29  .Having forced circulation system
  235.31  .Having specific intenal drum and head structure
  235.32  .With combustion
  235.33  .With convection zone regulation
  235.34  .With parallel multiple fireboxes
  235.35  .With serial multiple fireboxes
  238     .Offset fireboxx
  239     .Superimposed firebox
  240.1   .Having plural fireboxes
  240.2   ..Series connected
  240.3   ..Parallel connected
  241     .Firebox in drum
  242     .Capillary
  243     ..Fluid fuel
         .Coil or loop
  244     ..Central standpipe
  245     ...Fluid fuel
  246     ...Annular firebox
  247     .Coil
         ..Horizontal
  248     ...Fluid fuel
  249     ..Vertical
  250 R   ...Fluid fuel
  250 S   ....Standpipe
  251     ...Central magazine
  252     ...Water firebox
  253     .Cross
  254     ..Over bridge wall
         ..Over firebox
         ...Longitudinal
         ....Header
  255     .....Drum
         ...Transverse
         ....Header
  256     .....Drum
         ..Transverse
         ...Header
  257     ....Drum
  258     .Downflow
  259     .Drum type
  260     .Flat
  261     ..Volute
  262     .Horizontal
  263     ..Over bridge wall
  264     ..Over firebox
  265     .Inclined
  266     .Internal fire tube
  267     ..Horizontal
  268     ..Inclined
  269     ..Plural fire tube
  270     ..Straddle
  271     ..Vertical
  272     ...Central magazine
  273     .Longitudinal upper drum
  274     ..Fluid fuel
  275     .Loop
  276     ..Firebox enclosing
  277     ..Over bridge wall
         ..Over firebox
  278     ...Cross
  279     ...Horizontal
         ...Rear of bridge wall
  280     ....Bridge wall header
  281     ...Standpipe
  282     ...Verticall
  283     ....Fluid fuel
         .Over bridge wall
  284     ..Headers at right angles
  285     ..Transverse water baffle
         ..Water grate
  286     ...Downdraft
  287     ...Intermediate draft
         .Over firebox
  288     ..Headers at right angles
         ..Water grate
  289     ...Updraft
         .Rearwardly declined
         ..Over bridge wall
  290     ...Front and rear header
  291     ....Horizontal-longitudinal drum
  292     .....Firebox tube
  293     .....Longitudinal water baffle
  294     .....Water wall
  295     ....Internal water tube
  296     ....Longitudinal-declined drum
  297     ....Transverse drum
         ..Over firebox
         ...Front and rear header
  298     ....Horizontal-longitudinal drum
  299     ....Transverse drum
  300     ....Tubes beyond side wall
         ..Plural upper transverse drum
  301     ...Plural lower transverse drum
  302     ...Single lower transverse drum
         .Rearwardly inclined
         ..Over firebox
         ...Front and rear header
  303     ....Transverse drum
         .Separate banks
  304     ..Opposite fireboxes
  305     .Spur
  306     ..Bridge wall header
  307     ..Central standpipe
  308     ...Fluid fuel
  309     ...Annular firebox
  310     ...Central magazine
  311     ..Cross
  312     ..Horizontal-longitudinal drum
  313     ..Over bridge wall
         ..Over firebox
  314     ...Central header
  315     ...Declined
  316     ...Horizontal
  317     ..Straddle
  318     ..Vertical
  319     ...Fluid fuel
  320     ...Central magazine
  321     .Standpipe
  322     ..Fluid fuel
  323     ..Annular firebox
  324     .Straddle
         ..Plural upper drum
  325     ...Plural lower drumm
  326     ....Cross
         ..Single upper drum
  327     ...Plural lower drum
  328     ....Fluid fuel
  329     ....Cross
  330     ....Plural firebox
  331     .Transverse horizontal drum
  332     .Vertical
  333     ..Fluid fuel
  334     ..Side magazine
  335     ..Annular firebox
  336     ..Offset firebox
  337     ...Elevated
         ..Annular lower drum
  338     ...Annular upper drum
  339     ....Central magazine
  340     ....Tubes over firebox
  341     ...Fire tube upper drum
  342     ...Spur tube upper drum
  343     ...Upper drum
  344     ....Central magazine
  345     ..Beyond bridge wall
  346     ...Gas return
         ...Longitudinal upper drum
  347     ....Longitudinal lower drum
         ..Internal fire tube
  348     ...Fluid fuel
  349     ..Over firebox
  350     ...Gas return
         ..Plural upper longitudinal drum
  351     ...Plural lower longitudinal drum
         ..Plural upper transverse drum
         ...Plural lower transverse drum
  352     ....Offset firebox
  353     .Water grate
  354     ..Downdraft
  355     .Zigzag
  356     ..Fluid fuel
         ..Over bridge wall
  357     ...Longitudinal drum
  358     ...Transverse drum
  359     ..Over firebox
  237     .Magazine
  236     .Fluid fuel
         .Headers
  360     ..Closures and couplings
  361     ...Cleaning
  362     ...Concentric tube
  363     ...Drum
  364     ...Tube closures
  365     .Drums and couplings
  366     WICK
  367.1   HEAT TRANSMITTER
  367.2   .Double immersed heat transmitters
  367.3   .Corrugated and finned heat transmitters
  367.4   .Pebble furnaces
  368     WATER FIREBOX
  369     .Mud ringg
  370     .Plural
  371     WATER GRATE
         .Plural firebox
         ..Superimposed
         ...Water grate
  372     ....Updraft
  373     .Cage
  374     .Grate structure
  375     ..Solid and water bar
  376     .Progressive feed
         .Water firebox
         ..Solid and water bar
  377     ...Updraft
  378     ..Updraft
  21      CHEMICAL
  22      FLUID AND SOLID FUEL
  23      FLUID FUEL
  24      .Explosion
         .Plural burner
  25      ..Superimposed
  26      FRICTION GENERATOR
  *       NONCOMBUSTIBLE HEATER
  27      .Surface
  28      .Water in contact
  379     CLEANING
  380     .Agitating circulator
         .Blow off
  381     ..Bottom and surface
  382     ..Bottom
  383     ...Internal conduit
  384     ....Ejector
  385     ....Mud ring
  386     ....Pan
  387     ....Scraper
  388     ....Valved
  389     ..Surface exit
  390     .Fluid jet
  391     ..Horizontal fire tube boiler
  392     ..Water tube boiler
  393     .Mud drum
  394     .Pans
  395     .Sandblast
  396     .Systems
  397     .Trapped circuit
  398     ..Feeding water
  399     ..Surface and bottom exit
  400     ..Surface exit
  401     ...Chemical feeder
  402     ...Circulating pump
  403     ...Feed heater
  404     ...Steam injector
  405     .Wash-out nozzle
  406.1   CIRCULATION
  406.2   .Having anticavitation devices
  406.3   .Having restrictors and orifices
  406.4   .Once through
  406.5   .With start-up operations
  407     .Injectorr
  408.1   .Having internal conduit
  408.2   ..With internal geyser tube
  409     ..Horizontal flue boiler
  410     ...Return fire tube
         .Mechanical
  411     ..Internal
  412     FEED HEATERS
  413     .Ash pan
         .Boiler circuit
  414     ..Feed-injected
         .Circulatioon
         ..Surface exit
         ...Mechanical pump
  415     ....Feed-injected
  417     .Drip plate in boiler
         .Fire-engine boiler
         ..Auxiliary
  418     ...Attached
  419     ...Detachable
  420     .Furnace gases
  421     .Offtake flue
  422     .Furnace gases and steam
         .Horizontal fire tube boiler
  423     ..Smoke box
  424     ...Exhaust pipe
  425     ...Furnace gases and steam
  426     ...Water tube
  427     ..Smoke chamber
  428     .Internal conduit
  429     ..Automatic sediment valve
  430     ..Blow-off delivery
  431     ..Filter in boiler
  432     ..Furnace gases
  433     ..Trap outside boiler
  434     .Locomotive tender
  435     .Pan in steam space
  436     ..Spray
  437     .Safety valve
  438     .Spray to steam space
  439     .Stack
  441     .Steam
  442     ..Injected
         ...Superposed
  443     ....Open to steam space
  444     .Water tube boiler
  *       REGULATION
         .Fuel and water
  446     ..Fluid fuel
  447     ...Cutoff
         ..Automatic control
  449     ...Solid fuel
  450     .Suspended boiler
  448.1   AUTOMATIC CONTROL OF FLUID FUEL AND WATER
  448.2   .Having fuel or feed bypass
  448.3   .Multiple boiler regulation
  448.4   .Once through
  451 R   FEEDERS
  451.1   .Automaticc
  451.1   ..Thermally controlled
  451.2   ...Pressure-operated valve
  452     .Boiler pressure
         .Gravity
  456     ..Automatic
  457     ...Heater
  458     ..Heater
  451 S   .Once through
  459     STEAM TREATMENT
  460     .Boilers with superheaters
         .Fire tube boiler
         ..Horizontal
  461     ...Superheater
         ....In fire tube
  462     .....From smoke box
         ....Interior steam space
  463     .....Internal fire tube
         ....Smoke box
  464     .....Fire tube
  465     .....Steam tube
  466     ..Superheater and feed heater
         ..Vertical
  467     ...Superheater
         .Flue boiler
         ..Vertical
         ...Internal water tube
  468     ....Superheater
         .Horizontal boiler
         ..Superheater
  469     ...Rear of firebox
  470     ...Waste-heat flue
         .Water tube boiler
         ..Declined over bridge wall
         ...Front and rear header
         ....Declined drum
  471     .....Superheater
         ....Longitudinal drum
  472     .....Superheater
         ..Longitudinal drum
  473     ...Superheater
         ..Over bridge wall
  474     ...Superheater
         ..Standpipe
         ...Spur tube
  475     ....Superheater
         ..Transverse drum
  478     ...Superheater
  477     ..Superheater and feed heater
  476     ..Superheater
         .Superheater
  480     ..Damper-controlled
  481     ..Firebox
  482     ..Fire tube in steam space
  483     ..Indirectly heated
  484     ..Separate charges
  485     ..Separate furnace
  486     ..Steam dome
  487     ..Water-injectedd
  479.1   .Automatic heat regulation of superheater
  479.2   ..Having gas recirculation
  479.3   ..Having flame positioning
  479.4   ..With variable firing
  479.5   ..Having dampers
  479.6   ..Plural furnaces
  479.7   ..Once through
  *       SEPARATORS
  488     .Boiler circulation
  489     .Boiler return
  490     .For tilting boilers
  491     .Interior of boilers
  492     .Steam dome
  493     BRACES AND STAYS
  494     CASINGS
  495     CROWN SHEETS PROTECTING
  496     CROWN SHEETS AND STAYS
  497     FRONTS
  498     .Doors
  499     .Mouths
  500     ..Water firebox
  501     FLUID-DISPLACER
  502     .Fluid fuel
  503     FUEL BAFFLES
  504     SAFETY DEVICES
  504.1   .Fusible control
  504.2   .Alarms or indicators
  504.3   .Fire extinguishers
  504.3   ..Fusible control
  505     ..Float-controlled
  506     ..Pressure-controlled
  507     .Self-closing valve
  508     STEAM DOMES
  509     SUBMERGED STEAM CHAMBER
  510     SUPPORTS
  511     TUBES AND CONNECTIONS
  512     TUBE SHEETS
  *       ******************************
  *       DIGESTS
  *       ******************************
  DIG 1   Air heater
  DIG 2   Air heater - indirectly heated
  DIG 3   Gas flow baffles
  DIG 4   Once through boilers
  DIG 5   Critical pressure
  DIG 6   Damper-directed radiation
  DIG 7   Feeding air
  DIG 10  Portable units
  DIG 11  Removable steam-heating elements
  DIG 13  Tubes - composition and protection
  DIG 14  Tube replacement
  DIG 15  Valves
  DIG 16  Welding