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
 F22
STEAM GENERATION (chemical or physical apparatus for generating gases B01J; chemical generation of gas, e.g. under pressure, Section C; removal of combustion products or residues, e.g. cleaning of the combustion contaminated surfaces of tubes of boilers, F23J; generating combustion products of high pressure or high velocity F23R; water heaters not for steam generation F24H, F28; cleaning of internal or external surfaces of heat-transfer conduits, e.g. water tubes of boilers, F28G)
 F22

Note(s)

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

  • "steam" covers also other condensable vapours, e.g. mercury, diphenyl, diphenyl oxide.

 F22D
PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER; FEED-WATER SUPPLY; CONTROLLING WATER LEVEL; CIRCULATING WATER WITHIN BOILERS (chemical treatment of water, e.g. purification, C02F; enclosed heat-exchange apparatus in general F28D; controlling in general G05)
 F22D 1/00
Feed-water heaters, e.g. preheaters
 F22D 1/02
·  with water tubes arranged in the boiler furnace, fire tubes, or flue ways (heat-exchange tubes in general F28F)
 F22D 1/04
·  ·  the tubes having plain outer surfaces, e.g. in vertical arrangement
 F22D 1/06
·  ·  ·  in horizontal arrangement
 F22D 1/08
·  ·  the tubes having fins, ribs, gills, corrugations, or the like on their outer surfaces, e.g. in vertical arrangement
 F22D 1/10
·  ·  ·  in horizontal arrangement (hollow fire-bars, grates, or the like used as water tubes F23H 3/02)
 F22D 1/12
·  ·  Control devices, e.g. for regulating steam temperature
 F22D 1/14
·  ·  Safety or venting devices (safety devices for boilers in general F22B 37/42)
 F22D 1/16
·  with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways
 F22D 1/18
·  ·  and heated indirectly
 F22D 1/20
·  ·  and directly connected to boilers
 F22D 1/22
·  ·  and provided for rotary movement
 F22D 1/24
·  with fire tubes or flue ways traversing feed-water vessels
 F22D 1/26
·  with means, other than tubes, to separate water and heating medium, e.g. bulk heaters without internal flues or tubes, jacketted smoke-boxes or flues
 F22D 1/28
·  for direct heat transfer, e.g. by mixing water and steam
 F22D 1/30
·  ·  with stages, steps, baffles, dishes, circular troughs, or other means to cause interrupted or cascading fall of water
 F22D 1/32
·  arranged to be heated by steam, e.g. bled from turbines
 F22D 1/34
·  ·  and returning condensate to boiler with main feed supply
 F22D 1/36
·  Water and air preheating systems
 F22D 1/38
·  ·  Constructional features of water and air preheating systems
 F22D 1/40
·  Combinations of exhaust-steam and smoke-gas preheaters (for locomotives F22D 1/42)
 F22D 1/42
·  specially adapted for locomotives
 F22D 1/44
·  ·  Smoke-gas preheaters
 F22D 1/46
·  ·  Exhaust-steam preheaters
 F22D 1/48
·  ·  Details
 F22D 1/50
·  incorporating thermal de-aeration of feed-water (de-aeration produced in the course of direct heat transfer F22D 1/28; thermal de-aeration of water per se B01D 19/00, C02F 1/20; valves for venting F16K 24/04)  [3]
 F22D 3/00
Accumulators for preheated water
 F22D 3/02
·  arranged within combustion chambers
 F22D 3/04
·  combined with steam accumulators
 F22D 3/06
·  directly connected to boilers
 F22D 3/08
·  specially adapted for locomotives (locomotive boilers F22B 13/06)
 F22D 3/10
·  ·  Control devices (controlling water feed to boilers, or water level F22D 5/00)
 F22D 5/00
Controlling water feed or water level; Automatic water feeding or water-level regulators (steam traps F16T; measuring or indicating instruments G01; for indicating water level G01F; level control in general G05D 9/00)
 F22D 5/02
·  with an intermediate compartment from which the water is fed by gravity after mechanically moving the compartment, the movement being controlled according to water level
 F22D 5/04
·  with pivoting buckets
 F22D 5/06
·  with receptacles external to, but in free communication with, the boilers and adapted to move up and down in accordance with change in water level
 F22D 5/08
·  with float-actuated valves
 F22D 5/10
·  ·  and with pistons or membranes unitary with the feed inlet valves
 F22D 5/12
·  ·  and with dipping tubes
 F22D 5/14
·  responsive to thermal expansion and contraction, e.g. of solid elements
 F22D 5/16
·  ·  of fluids
 F22D 5/18
·  for varying the speed or delivery pressure of feed pumps
 F22D 5/20
·  ·  without floats
 F22D 5/22
·  ·  with floats
 F22D 5/24
·  with electric switches
 F22D 5/26
·  Automatic feed-control systems (automatic safety devices F22B 37/42; controlling in general G05)
 F22D 5/28
·  ·  responsive to amount of steam withdrawn; responsive to steam pressure
 F22D 5/30
·  ·  responsive to both water level and amount of steam withdrawn or steam pressure
 F22D 5/32
·  ·  influencing the speed or delivery pressure of the feed pumps
 F22D 5/34
·  ·  Applications of valves (valves per se F16K)
 F22D 5/36
·  ·  for feeding a number of steam boilers designed for different ranges of temperature and pressure
 F22D 7/00
Auxiliary devices or apparatus for promoting water circulation
 F22D 7/02
·  Saddles or like directing plates fitted to furnace tubes
 F22D 7/04
·  Injectors for water or steam
 F22D 7/06
·  Rotary devices, e.g. propellers
 F22D 7/08
·  ·  Arrangements of pumps, e.g. outside the boilers
 F22D 7/10
·  ·  ·  within the boilers
 F22D 7/12
·  Control devices
 F22D 7/14
·  specially adapted for locomotive boilers
 F22D 11/00
Feed-water supply not provided for in other main groups
 F22D 11/02
·  Arrangements of feed-water pumps (F22D 11/06 takes precedence; pumps per se F04)
 F22D 11/04
·  ·  with means to eliminate steam formation
 F22D 11/06
·  ·  for returning condensate to boiler