F
SECTION F — MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
 F01 - 
F42

Note(s)

Guide to the use of this subsection (classes F01-F04)

The following notes are meant to assist in the use of this part of the classification scheme.

  1. In this subsection, subclasses or groups designating "engines" or "pumps" cover methods of operating the same, unless otherwise specifically provided for.
  2. In this subsection, the following terms or expressions are used with the meanings indicated:
    • "engine" means a device for continuously converting fluid energy into mechanical power. Thus, this term includes, for example, steam piston engines or steam turbines, per se, or internal-combustion piston engines, but it excludes single-stroke devices. "Engine" also includes the fluid-motive portion of a meter unless such portion is particularly adapted for use in a meter;
    • "pump" means a device for continuously raising, forcing, compressing, or exhausting fluid by mechanical or other means. Thus, this term includes fans or blowers;
    • "machine" means a device which could equally be an engine and a pump, and not a device which is restricted to an engine or one which is restricted to a pump;
    • "positive displacement" means the way the energy of a working fluid is transformed into mechanical energy, in which variations of volume created by the working fluid in a working chamber produce equivalent displacements of the mechanical member transmitting the energy, the dynamic effect of the fluid being of minor importance, and vice versa;
    • "non-positive displacement" means the way the energy of a working fluid is transformed into mechanical energy, by transformation of the energy of the working fluid into kinetic energy, and vice versa;
    • "oscillating-piston machine" means a positive-displacement machine in which a fluid-engaging work-transmitting member oscillates. This definition applies also to engines and pumps;
    • "rotary-piston machine" means a positive-displacement machine in which a fluid-engaging work-transmitting member rotates about a fixed axis or about an axis moving along a circular or similar orbit. This definition applies also to engines and pumps;
    • "rotary piston" means the work-transmitting member of a rotary-piston machine and may be of any suitable form, e.g., like a toothed gear;
    • "cooperating members" means the "oscillating piston" or "rotary piston" and another member, e.g., the working-chamber wall, which assists in the driving or pumping action;
    • "movement of the co-operating members" is to be interpreted as relative, so that one of the "co-operating members" may be stationary, even though reference may be made to its rotational axis, or both may move;
    • "teeth or tooth equivalents" include lobes, projections or abutments;
    • "internal-axis type" means that the rotational axes of the inner and outer co-operating members remain at all times within the outer member, e.g., in a similar manner to that of a pinion meshing with the internal teeth of a ring gear;
    • "free piston" means a piston of which the length of stroke is not defined by any member driven thereby;
    • "cylinders" means positive-displacement working chambers in general. Thus, this term is not restricted to cylinders of circular cross-section;
    • "main shaft" means the shaft which converts reciprocating piston motion into rotary motion or vice versa;
    • "plant" means an engine together with such additional apparatus as is necessary to run the engine. For example, a steam engine plant includes a steam engine and means for generating the steam;
    • "working fluid" means the driven fluid in a pump and the driving fluid in an engine. The working fluid may be in a gaseous state, i.e., compressible, or liquid. In the former case coexistence of two states is possible;
    • "steam" includes condensable vapours in general, and "special vapour" is used when steam is excluded;
    • "reaction type" as applied to non-positive-displacement machines or engines means machines or engines in which pressure/velocity transformation takes place wholly or partly in the rotor. Mmachines or engines with no, or only slight, pressure/velocity transformation in the rotor are called "impulse type".
  3. In this subsection:
  4. For use of this subsection with a good understanding, it is essential to remember, so far as subclasses F01B, F01C, F01D, F03B, and F04B, F04C, F04D, which form its skeleton, are concerned:
    • the principle which resides in their elaboration,
    • the classifying characteristics which they call for, and
    • their complementarity.
      1. Principle

        This concerns essentially the subclasses listed above. Other subclasses, notably those of class F02, which cover better-defined matter, are not considered here.

        Each subclass covers fundamentally a genus of apparatus (engine or pump) and by extension covers equally "machines" of the same kind. Two different subjects, one having a more general character than the other, are thus covered by the same subclass.

        Subclasses F01B, F03B, F04B, beyond the two subjects which they cover, have further a character of generality in relation to other subclasses concerning the different species of apparatus in the genus concerned.

        This generality applies as well for the two subjects dealt with, without these always being in relation to the same subclasses.

        Thus, subclass F03B, in its part dealing with "machines", should be considered as being the general class relating to subclasses F04B, F04C, and in its part dealing with "engines" as being general in relation to subclass F03C.

      2. Characteristics

        The principal classifying characteristic of the subclass is that of genera of apparatus, of which there are three possible:

        Machines; engines; pumps.

        As stated above, "machines" are always associated with one of the other two genera. These main genera are subdivided according to the general principles of operation of the apparatus:

        Positive displacement; non-positive displacement.

        The positive displacement apparatus are further subdivided according to the ways of putting into effect the principle of operation, that is, to the kind of apparatus:

        Simple reciprocating piston; rotary or oscillating piston; other kind.

        Another classifying characteristic is that of the working fluid, in respect of which three kinds of apparatus are possible, namely:

        Liquid and elastic fluid; elastic fluid; liquid.

      3. Complementarity

        This resides in association of pairs of the subclasses listed above, according to the characteristics under consideration in respect of kind of apparatus or working fluid.

        The subclasses concerned with the various principles, characteristics and complementarity are shown in the following table:

It is seen from this table that:

  
LIGHTING; HEATING
 F24
HEATING; RANGES; VENTILATING (protecting plants by heating in gardens, orchards, or forests A01G 13/06; baking ovens and apparatus A21B; cooking devices other than ranges A47J; forging B21J, B21K; specially adapted for vehicles, see the relevant subclasses of classes B60-B64; combustion apparatus in general F23; drying F26B; ovens in general F27; electric heating elements or arrangements H05B)
 F24

Note(s)

In this class, the following terms are used with the meanings indicated:

  • "stove" includes apparatus which may have an open fire, e.g. fireplace;
  • "range" means an apparatus for cooking having elements that perform different cooking operations or cooking and heating operations.

 F24D
DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR (preventing corrosion C23F; water supply in general E03; using steam or condensate extracted or exhausted from steam engine plants for heating purposes F01K 17/02; steam traps F16T; domestic stoves or ranges F24B, F24C; water or air heaters having heat generating means F24H; combined heating and refrigeration systems F25B; heat exchange apparatus or elements F28; removing furring F28G)
 F24D

Note(s)

In this subclass, the following expression is used with the meaning indicated:

  • "central heating system" means a system in which heat is generated or stored at central sources and is distributed by means of a transfer fluid to the spaces or areas to be heated. [5]

 F24D
Subclass index
CENTRAL HEATING SYSTEMS
With heat-transfer fluid: steam; hot water; hot air or exhaust gas; other fluid 1/00; 3/00; 5/00; 7/00
Combinations 9/00
District heating systems 10/00
By heat storage 11/00
Other systems 12/00
OTHER DOMESTIC- OR SPACE-HEATING SYSTEMS
Electric; Other 13/00; 15/00
DOMESTIC HOT-WATER SUPPLY 17/00
DETAILS 19/00
 F24D 1/00 - 
F24D 12/00
Central heating systems
 F24D 1/00
Steam central heating systems (F24D 10/00, F24D 11/00 take precedence)
 F24D 1/02
·  operating with live steam
 F24D 1/04
·  operating with exhaust steam
 F24D 1/06
·  operating with superheated steam
 F24D 1/08
·  Feed-line arrangements, e.g. providing for one-pipe system
 F24D 3/00
Hot-water central heating systems (F24D 10/00, F24D 11/00 take precedence)
 F24D 3/02
·  with forced circulation, e.g. by pumps
 F24D 3/04
·  with the water under high pressure
 F24D 3/06
·  ·  Arrangements or devices for maintaining high pressure
 F24D 3/08
·  in combination with systems for domestic hot-water supply
 F24D 3/10
·  Feed-line arrangements, e.g. providing for heat-accumulator tanks, expansion tanks
 F24D 3/12
·  Tube and panel arrangements for ceiling, wall, or underfloor heating (electric underfloor heating F24D 13/02; special adaptations of floors for incorporating ducts, e.g. for heating or ventilating, E04B 5/48; building elements of block or other shape for the construction of parts of buildings characterised by special adaptations, e.g. serving for locating conduits, E04C 1/39; building elements of relatively thin form for the construction of parts of buildings with special adaptations for auxiliary purposes, e.g. serving for locating conduits, E04C 2/52)  [4]
 F24D 3/14
·  ·  incorporated in a ceiling, wall or floor  [4]
 F24D 3/16
·  ·  mounted on, or adjacent to, a ceiling, wall or floor  [4]
 F24D 3/18
·  using heat pumps  [5]
 F24D 5/00
Hot-air central heating systems (F24D 10/00, F24D 11/00 take precedence; air conditioning F24F); Exhaust-gas central heating systems
 F24D 5/02
·  operating with discharge of hot air into the space or area to be heated
 F24D 5/04
·  ·  with return of the air to the air heater
 F24D 5/06
·  operating without discharge of hot air into the space or area to be heated
 F24D 5/08
·  ·  with hot air led through radiators
 F24D 5/10
·  ·  with hot air led through heat-exchange ducts in the walls, floor, or ceiling
 F24D 5/12
·  using heat pumps  [5]
 F24D 7/00
Central heating systems employing heat-transfer fluids not covered by groups F24D 1/00-F24D 5/00, e.g. oil, salt, gas (F24D 10/00, F24D 11/00 take precedence)
 F24D 9/00
Central heating systems employing combinations of heat-transfer fluids covered by two or more of groups F24D 1/00-F24D 7/00 (F24D 10/00, F24D 11/00 take precedence)
 F24D 9/02
·  Hot water and steam systems
 F24D 10/00
District heating systems  [5]
 F24D 11/00
Central heating systems using heat accumulated in storage masses (self-contained storage heating units F24D 15/02; storage masses, see the relevant subclasses)
 F24D 11/02
·  using heat pumps
 F24D 12/00
Other central heating systems
 F24D 12/02
·  having more than one heat source (F24D 3/18, F24D 5/12, F24D 11/02 take precedence)  [5]
 F24D 13/00 - 
F24D 15/00
Other domestic- or space-heating systems
 F24D 13/00
Electric heating systems (electric water or air heaters F24H)
 F24D 13/02
·  solely using resistance heating, e.g. underfloor heating
 F24D 13/04
·  using electric heating of heat-transfer fluid in separate units of the system
 F24D 15/00
Other domestic- or space-heating systems
 F24D 15/02
·  consisting of self-contained heating units, e.g. storage heaters  [3]
 F24D 15/04
·  using heat pumps  [5]
 F24D 17/00
Domestic hot-water supply systems (combined with domestic- or space-heating systems F24D 1/00-F24D 15/00)
 F24D 17/02
·  using heat pumps  [5]
 F24D 19/00
Details (of water or air heaters F24H 9/00; of heat-exchange or heat-transfer apparatus, of general application F28F)  [3]
 F24D 19/02
·  Arrangement of mountings or supports for radiators  [3]
 F24D 19/04
·  ·  in skirtings  [3]
 F24D 19/06
·  Casings, cover lids or ornamental panels, for radiators  [3]
 F24D 19/08
·  Arrangements for drainage, venting or aerating (valves for drainage F16K, e.g. F16K 21/00, for venting or aerating F16K 24/00)  [3]
 F24D 19/10
·  Arrangement or mounting of control or safety devices (control valves F16K; only the heater being controlled F24H 9/20)  [3]