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
 F25
REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION OR SOLIDIFICATION OF GASES
 F25B
REFRIGERATION MACHINES, PLANTS, OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS (pumps, compressors F04; use of heat pumps for domestic or space-heating or for domestic hot-water supply F24D; air-conditioning, air-humidification F24F; fluid heaters using heat pumps F24H)
 F25B

Note(s)

  1. Attention is drawn to Note (2) following the title of subclass F24F[5]
  2. When classifying heat pump circuits or systems, groups F25B 1/00-F25B 25/00 and F25B 29/00 take precedence over group F25B 30/00[5]
 F25B
Subclass index
MODE OF OPERATION
Compression type
characterised by the cycle 1/00, 13/00
characterised by the arrangement
self-contained rotary; with several evaporation circuits; with several condenser circuits; with cascade operation 3/00; 5/00; 6/00; 7/00
characterised by the refrigerant 9/00
using turbines 11/00
Sorption type 15/00, 17/00
Other types having a single mode of operation, using: evaporation without recovery; electric or magnetic effects; other effect 19/00; 21/00; 23/00
Combinations: of above modes of operation; of heating and refrigerating 25/00; 29/00
Heat pumps 30/00
Using special energy source 27/00
DETAILS, ARRANGEMENTS, OR COMPONENTS
Components: boilers, analysers, rectifiers; boiler-absorbers; absorbers, adsorbers; evaporators, condensers; subcoolers, desuper- heaters, superheaters 33/00; 35/00; 37/00; 39/00; 40/00
Arrangements
compressor arrangement; fluid circulation; separating or purifying gases 31/00; 41/00; 43/00
for charging or discharging refrigerant; for combating corrosion or deposits 45/00; 47/00
Mounting of control and safety devices 49/00

 F25C
PRODUCTION, WORKING, STORING, OR DISTRIBUTION OF ICE (frozen sweets, including ice-cream, their production A23G 9/00; concentrating solutions by removing frozen solvents B01D 9/04; purification of water by freezing C02F 1/22; refrigeration machines, plants, or systems F25B; solidification of gases or gaseous mixtures F25J; freeze-drying F26B)  [2]
 F25C

Note(s)

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

  • "ice" means any frozen liquid and also covers frozen semiliquids or pasty substances. [2]


 F25D
REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT COVERED BY ANY OTHER SUBCLASS (refrigerated showcases A47F 3/04; thermally-insulated vessels for domestic use A47J 41/00; refrigerated vehicles, see the appropriate subclasses of classes B60-B64; containers with thermal insulation in general B65D 81/38; thermally-insulated vessels for liquefied or solidified gases F17C; air-conditioning or air-humidification F24F; refrigeration machines, plants, or systems F25B; cooling of instruments or comparable apparatus without refrigeration G12B; cooling of engines or pumps, see the relevant classes)
 F25D

Note(s)

  1. In this subclass, the following term is used with the meaning indicated:
    • "device" means an enclosed space to be cooled; such devices being associated either with refrigerating machinery, e.g. in a refrigerator, or with other cold sources, e.g. in an ice-box.
  2. Attention is drawn to Note (2) following the title of subclass F24F[5]
 F25D
Subclass index
DEVICES NOT ASSOCIATED WITH REFRIGERATING MACHINERY
Using cold air or water; other cold materials or bodies 1/00; 3/00
Using endothermic chemical reactions, or evaporation without recovery 5/00, 7/00
Other devices, combinations 9/00
DEVICES ASSOCIATED WITH REFRIGERATING MACHINERY: SELF-CONTAINED MOVABLE; STATIONARY; OTHER 11/00; 13/00; 15/00, 16/00
STRUCTURAL PARTS OR ARRANGEMENTS, OF GENERAL APPLICATION: GENERAL; DEFROSTING; HANDLING OF ARTICLES TO BE COOLED 23/00; 21/00; 25/00
CIRCULATING COOLING FLUID OR GAS; LIGHTING 17/00; 27/00
ARRANGEMENT OR MOUNTING: OF REFRIGERATION UNITS; OF CONTROL OR SAFETY DEVICES 19/00; 29/00
OTHER APPARATUS 31/00

 F25J
LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT (cryogenic pumps F04B 37/08; gas storage vessels, gas-holders F17; filling vessels with, or discharging from vessels, compressed, liquefied, or solidified gases F17C; refrigeration machines, plants, or systems F25B)