F
SECTION F — MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  
ENGINES OR PUMPS
 F01 - 
F04

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

          Machines; engines; pumps.

        2. 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.

        3. 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.

        4. 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 subsection index below.

It is seen from this index that:

 F01 - 
F04
Subsection index
MACHINES
positive displacement
rotary or oscillating piston
liquid and elastic fluid or elastic fluidF01C
liquid onlyF04C
reciprocating piston or other
liquid and elastic fluid or elastic fluidF01B
liquid onlyF04B
non-positive displacement
liquid and elastic fluid or elastic fluidF01D
liquid onlyF03B
ENGINES
positive displacement
rotary or oscillating piston
liquid and elastic fluid or elastic fluidF01C
liquid onlyF03C
reciprocating piston or other
liquid and elastic fluid or elastic fluidF01B
liquid onlyF03C
non-positive displacement
liquid and elastic fluid or elastic fluidF01D
liquid onlyF03B
PUMPS
positive displacement
rotary or oscillating pistonF04C
reciprocating piston or otherF04B
non-positive displacementF04D
 F04
POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS (portable fire extinguishers with manually-operated pumps A62C 11/00, with power-driven pumps A62C 25/00; charging or scavenging combustion engines by pumps F02B; engine fuel-injection pumps F02M; ion pumps H01J 41/12; electrodynamic pumps H02K 44/02)
 F04

Note(s)

Combinations of positive-displacement and non-positive-displacement pumps are classified in subclass F04B as a general subclass for pumps, and in subclasses F04C, F04D in respect of matter specific to those subclasses.

 F04B
POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F; crankshafts, crossheads, connecting-rods F16C; flywheels F16F; gearings for interconverting rotary motion and reciprocating motion in general F16H; pistons, piston-rods, cylinders, in general F16J)
 F04B

Note(s)

  1. In this subclass, the following term is used with the meaning indicated:
    • "piston" also covers a plunger.
  2. Attention is drawn to the Notes following the titles of class B81 and subclass B81B relating to "micro-structural devices" and "micro-structural systems". [7]
  3. Attention is drawn to the Notes preceding class F01, especially as regards the definitions of "machines", "pumps", and "positive-displacement".
 F04B
Subclass index
POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS, PUMPS IN GENERAL
General characteristics of machines and pumps
multiple cylinders; single cylinders, pistons coacting in cylinder; differential-surface pistons; flexible working members 1/00; 3/00; 5/00; 43/00
positively-driven distribution members; driving or driven means to or from working members 7/00; 9/00
equalization of pulses, counteracting cavitation 11/00
other characteristics 19/00
Characteristics peculiar to pumps, their adaptations or combinations
delivering measured quantities; handling specific fluids; pumping from great depths 13/00; 15/00; 47/00
associated with specific driving engines 17/00
Other characteristics 19/00
Pumping installations or systems 23/00, 43/00, 47/00
Component parts, details or accessories 53/00
PUMPS FOR ELASTIC FLUIDS
General characteristics
multiple stages; multiple cylinders 25/00; 27/00
free piston; flexible working member; actuation by muscle power 31/00; 45/00; 33/00
driving means 35/00
For pumping from great depths 47/00
Other characteristics; other details or accessories 37/00; 39/00
Pumping installations or systems 41/00, 45/00, 47/00
CONTROL, SAFETY MEASURES; TESTING 49/00; 51/00
COMPONENT PARTS, DETAILS OR ACCESSORIES 53/00
 F04B 1/00 - 
F04B 23/00
Pumps for liquids or for liquid and elastic fluids; Positive-displacement machines for liquids (having flexible working members F04B 43/00; pumps for raising fluids from great depths F04B 47/00)
P:50 F04B 1/00
Multi-cylinder machines or pumps characterised by number or arrangement of cylinders (F04B 3/00 takes precedence; fluid-driven pumps F04B 9/08; control of reciprocating machines or pumps in general F04B 49/00)
 F04B 1/02
·  having two cylinders (in V-arrangement F04B 1/04)
 F04B 1/04
·  having cylinders in star- or fan-arrangement  [6]
 F04B 1/047
·  ·  with an actuating or actuated element at the outer ends of the cylinders  [6]
 F04B 1/053
·  ·  with an actuating or actuated element at the inner ends of the cylinders  [6]
 F04B 1/06
·  ·  Control
 F04B 1/07
·  ·  ·  by varying the relative eccentricity between two members, e.g. a cam and a drive shaft  [6]
 F04B 1/08
·  ·  ·  regulated by delivery pressure
 F04B 1/10
·  ·  the cylinders being movable, e.g. rotary  [6]
 F04B 1/107
·  ·  ·  with an actuating or actuated element at the outer ends of the cylinders  [6]
 F04B 1/113
·  ·  ·  with an actuating or actuated element at the inner ends of the cylinders  [6]
 F04B 1/12
·  having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
 F04B 1/14
·  ·  having stationary cylinders
 F04B 1/16
·  ·  ·  having two or more sets of cylinders or pistons
 F04B 1/18
·  ·  ·  having self-acting distribution members, i.e. actuated by working fluid
 F04B 1/20
·  ·  having rotary cylinder block
 F04B 1/22
·  ·  ·  having two or more sets of cylinders or pistons
 F04B 1/24
·  ·  ·  ·  inclined to main shaft axis
 F04B 1/26
·  ·  Control
 F04B 1/28
·  ·  ·  for machines or pumps with stationary cylinders
 F04B 1/29
·  ·  ·  ·  by varying the relative positions of a swash plate and a cylinder block  [6]
 F04B 1/30
·  ·  ·  for machines or pumps with rotary cylinder block
 F04B 1/32
·  ·  ·  ·  by varying the relative positions of a swash plate and a cylinder block  [6]
 F04B 1/34
·  Control not provided for in a single group of groups F04B 1/02-F04B 1/32  [6]
P:40 F04B 3/00
Machines or pumps with pistons coacting within one cylinder, e.g. multi-stage
P:60 F04B 5/00
Machines or pumps with differential-surface pistons
 F04B 5/02
·  with double-acting pistons  [6]
P:90 F04B 7/00
Piston machines or pumps characterised by having positively-driven valving (with cylinders in star- or fan-arrangement F04B 1/04; with cylinder axes coaxial with, or parallel or inclined to, main shaft axis F04B 1/12)
 F04B 7/02
·  the valving being fluid-actuated
 F04B 7/04
·  in which the valving is performed by pistons and cylinders coacting to open and close intake or outlet ports  [3]
 F04B 7/06
·  ·  the pistons and cylinders being relatively reciprocated and rotated  [3]
P:100 F04B 9/00
Piston machines or pumps characterised by the driving or driven means to or from their working members
 F04B 9/02
·  the means being mechanical
 F04B 9/04
·  ·  the means being cams, eccentrics, or pin-and-slot mechanisms (with cylinder axes coaxial with, or parallel or inclined to, main shaft axis F04B 1/12)
 F04B 9/06
·  ·  the means including spring- or weight-loaded lost-motion devices
 F04B 9/08
·  the means being fluid
 F04B 9/10
·  ·  the fluid being liquid
 F04B 9/103
·  ·  ·  having only one pumping chamber  [6]
 F04B 9/105
·  ·  ·  ·  reciprocating movement of the pumping member being obtained by a double-acting liquid motor  [6]
 F04B 9/107
·  ·  ·  ·  rectilinear movement of the pumping member in the working direction being obtained by a single-acting liquid motor, e.g. actuated in the other direction by gravity or a spring  [6]
 F04B 9/109
·  ·  ·  having plural pumping chambers  [6]
 F04B 9/111
·  ·  ·  ·  with two mechanically connected pumping members  [6]
 F04B 9/113
·  ·  ·  ·  ·  reciprocating movement of the pumping members being obtained by a double-acting liquid motor  [6]
 F04B 9/115
·  ·  ·  ·  ·  reciprocating movement of the pumping members being obtained by two single-acting liquid motors, each acting in one direction  [6]
 F04B 9/117
·  ·  ·  ·  the pumping members not being mechanically connected to each other  [6]
 F04B 9/12
·  ·  the fluid being elastic, e.g. steam or air
 F04B 9/123
·  ·  ·  having only one pumping chamber  [6]
 F04B 9/125
·  ·  ·  ·  reciprocating movement of the pumping member being obtained by a double-acting elastic-fluid motor  [6]
 F04B 9/127
·  ·  ·  ·  rectilinear movement of the pumping member in the working direction being obtained by a single-acting elastic-fluid motor, e.g. actuated in the other direction by gravity or a spring  [6]
 F04B 9/129
·  ·  ·  having plural pumping chambers  [6]
 F04B 9/131
·  ·  ·  ·  with two mechanically connected pumping members  [6]
 F04B 9/133
·  ·  ·  ·  ·  reciprocating movement of the pumping members being obtained by a double-acting elastic-fluid motor  [6]
 F04B 9/135
·  ·  ·  ·  ·  reciprocating movement of the pumping members being obtained by two single-acting elastic-fluid motors, each acting in one direction  [6]
 F04B 9/137
·  ·  ·  ·  the pumping members not being mechanically connected to each other  [6]
 F04B 9/14
·  Pumps characterised by muscle-power operation
P:70 F04B 11/00
Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation
P:80 F04B 13/00
Pumps specially modified to deliver fixed or variable measured quantities (for transferring liquid from bulk storage containers or reservoirs into vehicles or into portable containers B67D 5/40)
 F04B 13/02
·  of two or more fluids at the same time
P:110 F04B 15/00
Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
 F04B 15/02
·  the fluids being viscous or non-homogeneous
 F04B 15/04
·  the fluids being hot or corrosive (F04B 15/06 takes precedence)
 F04B 15/06
·  for liquids near their boiling point, e.g. under subnormal pressure
 F04B 15/08
·  ·  the liquids having low boiling points
P:120 F04B 17/00
Pumps characterised by combination with, or adaptation to, specific driving engines or motors
 F04B 17/02
·  driven by wind motors
 F04B 17/03
·  driven by electric motors  [6]
 F04B 17/04
·  ·  using solenoids  [6]
 F04B 17/05
·  driven by internal-combustion engines  [6]
 F04B 17/06
·  Mobile combinations
P:140 F04B 19/00
Machines or pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B 1/00-F04B 17/00
 F04B 19/02
·  having movable cylinders
 F04B 19/04
·  Pumps for special use (for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers B67D 5/40)
 F04B 19/06
·  ·  Pumps for delivery of both liquid and elastic fluids at the same time (wet gas pumps F04B 37/20)  [6]
 F04B 19/08
·  Scoop devices
 F04B 19/10
·  ·  of wheel type
 F04B 19/12
·  ·  of helical or screw type
 F04B 19/14
·  ·  of endless-chain type, e.g. with the chains carrying pistons co-operating with open-ended cylinders
 F04B 19/16
·  Adhesion-type liquid-lifting devices
 F04B 19/18
·  ·  Adhesion members therefor
 F04B 19/20
·  Other positive-displacement pumps
 F04B 19/22
·  ·  of reciprocating-piston type
 F04B 19/24
·  ·  Pumping by heat expansion of pumped fluid
P:130 F04B 23/00
Pumping installations or systems (F04B 17/00 takes precedence)
 F04B 23/02
·  having reservoirs
 F04B 23/04
·  Combinations of two or more pumps
 F04B 23/06
·  ·  the pumps being all of reciprocating positive-displacement type
 F04B 23/08
·  ·  the pumps being of different types
 F04B 23/10
·  ·  ·  at least one pump being of the reciprocating positive-displacement type
 F04B 23/12
·  ·  ·  at least one pump being of the rotary-piston positive-displacement type (F04B 23/10 takes precedence)
 F04B 23/14
·  ·  ·  at least one pump being of the non-positive-displacement type (F04B 23/10, F04B 23/12 take precedence)
 F04B 25/00 - 
F04B 41/00
Pumps specially adapted for elastic fluids (having a flexible working member F04B 45/00; for raising fluid from great depths F04B 47/00)
P:150 F04B 25/00
Multi-stage pumps
 F04B 25/02
·  of stepped-piston type
 F04B 25/04
·  having cylinders coaxial with, or parallel or inclined to, main shaft axis
P:160 F04B 27/00
Multi-cylinder pumps characterised by number or arrangement of cylinders (F04B 25/00 takes precedence; control of reciprocating machines or pumps in general F04B 49/00)
 F04B 27/02
·  having cylinders arranged oppositely relative to main shaft
 F04B 27/04
·  having cylinders in star- or fan-arrangement  [6]
 F04B 27/047
·  ·  with an actuating element at the outer ends of the cylinders  [6]
 F04B 27/053
·  ·  with an actuating element at the inner ends of the cylinders  [6]
 F04B 27/06
·  ·  the cylinders being movable, e.g. rotary
 F04B 27/067
·  ·  Control  [6]
 F04B 27/073
·  ·  ·  by varying the relative eccentricity between two members, e.g. a cam and a drive shaft  [6]
 F04B 27/08
·  having cylinders coaxial with, or parallel or inclined to, main shaft axis
 F04B 27/10
·  ·  having stationary cylinders  [6]
 F04B 27/12
·  ·  ·  having plural sets of cylinders or pistons  [6]
 F04B 27/14
·  ·  Control  [6]
 F04B 27/16
·  ·  ·  of pumps with stationary cylinders  [6]
 F04B 27/18
·  ·  ·  ·  by varying the relative positions of a swash plate and a cylinder block  [6]
 F04B 27/20
·  ·  ·  of pumps with rotary cylinder block  [6]
 F04B 27/22
·  ·  ·  ·  by varying the relative positions of a swash plate and a cylinder block  [6]
 F04B 27/24
·  Control not provided for in a single group of groups F04B 27/02-F04B 27/22  [6]
P:170 F04B 31/00
Free-piston pumps; Systems incorporating such pumps (muscle-driven pumps in which the stroke is not defined by gearing F04B 33/00; free-piston combustion engines, free-piston gas generators F02B 71/00; systems predominated by prime mover aspects, see the relevant class for the prime mover)
P:180 F04B 33/00
Pumps actuated by muscle power, e.g. for inflating
 F04B 33/02
·  with intermediate gearing
P:190 F04B 35/00
Piston pumps characterised by the driving means to their working members, or by combination with, or adaptation to, specific driving engines or motors, not otherwise provided for (predominant aspects of the engines or motors, see the relevant classes)
 F04B 35/01
·  the means being mechanical  [6]
 F04B 35/02
·  the means being fluid
 F04B 35/04
·  the means being electric
 F04B 35/06
·  Mobile combinations
P:210 F04B 37/00
Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B 25/00-F04B 35/00
 F04B 37/02
·  for evacuating by absorption or adsorption (absorption or adsorption in general B01J)
 F04B 37/04
·  ·  Selection of specific absorption or adsorption materials
 F04B 37/06
·  for evacuating by thermal means
 F04B 37/08
·  ·  by condensing or freezing, e.g. cryogenic pumps (cold traps B01D 8/00)
 F04B 37/10
·  for special use (F04B 37/02, F04B 37/06 take precedence)
 F04B 37/12
·  ·  to obtain high pressure
 F04B 37/14
·  ·  to obtain high vacuum
 F04B 37/16
·  ·  ·  Means for nullifying unswept space
 F04B 37/18
·  ·  for specific elastic fluids
 F04B 37/20
·  ·  ·  for wet gases, e.g. wet air
P:220 F04B 39/00
Component parts, details, or accessories, of pumps or pumping systems, not otherwise provided for in, or of interest apart from, groups F04B 25/00-F04B 37/00 (for controlling F04B 49/00)
 F04B 39/02
·  Lubrication (of machines or engines in general F01M)
 F04B 39/04
·  Measures to avoid lubricant contaminating the pumped fluid
 F04B 39/06
·  Cooling (of machines or engines in general F01P); Heating; Prevention of freezing
 F04B 39/08
·  Actuation of distribution members
 F04B 39/10
·  Adaptation or arrangement of distribution members
 F04B 39/12
·  Casings (casings for machines or engines in general F16M); Cylinders; Cylinder heads; Fluid connections
 F04B 39/14
·  Provisions for readily assembling or disassembling
 F04B 39/16
·  Filtration; Moisture separation
P:200 F04B 41/00
Pumping installations or systems (F04B 31/00, F04B 35/00 take precedence)
 F04B 41/02
·  having reservoirs
 F04B 41/04
·  Conversion of internal-combustion engine cylinder units to pumps
 F04B 41/06
·  Combinations of two or more pumps
 F04B 43/00 - 
F04B 45/00
Machines or pumps having flexible working members
P:30 F04B 43/00
Machines, pumps, or pumping installations having flexible working members (pumps or pumping installations specially adapted for elastic fluids F04B 45/00)
 F04B 43/02
·  having plate-like flexible members, e.g. diaphragms (F04B 43/14 takes precedence)  [3]
 F04B 43/04
·  ·  Pumps having electric drive
 F04B 43/06
·  ·  Pumps having fluid drive
 F04B 43/067
·  ·  ·  the fluid being actuated directly by a piston  [6]
 F04B 43/073
·  ·  ·  the actuating fluid being controlled by at least one valve  [6]
 F04B 43/08
·  having tubular flexible members (F04B 43/12 takes precedence)
 F04B 43/09
·  ·  Pumps having electric drive  [6]
 F04B 43/10
·  ·  Pumps having fluid drive
 F04B 43/107
·  ·  ·  the fluid being actuated directly by a piston  [6]
 F04B 43/113
·  ·  ·  the actuating fluid being controlled by at least one valve  [6]
 F04B 43/12
·  having peristaltic action
 F04B 43/14
·  ·  having plate-like flexible members  [3]
P:20 F04B 45/00
Pumps or pumping installations having flexible working members and specially adapted for elastic fluids
 F04B 45/02
·  having bellows
 F04B 45/027
·  ·  having electric drive  [6]
 F04B 45/033
·  ·  having fluid drive  [6]
 F04B 45/04
·  having plate-like flexible members, e.g. diaphragms (F04B 45/10 takes precedence)  [3]
 F04B 45/047
·  ·  Pumps having electric drive  [6]
 F04B 45/053
·  ·  Pumps having fluid drive  [6]
 F04B 45/06
·  having tubular flexible members (F04B 45/02, F04B 45/08 take precedence)  [3]
 F04B 45/067
·  ·  Pumps having electric drive  [6]
 F04B 45/073
·  ·  Pumps having fluid drive  [6]
 F04B 45/08
·  having peristaltic action  [3]
 F04B 45/10
·  ·  having plate-like flexible members  [3]
   
P:10 F04B 47/00
Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps (by using positive or negative pressurised fluid medium acting directly on the liquid to be pumped F04F 1/00)
 F04B 47/02
·  the driving mechanisms being situated at ground level (F04B 47/12 takes precedence)
 F04B 47/04
·  ·  the driving means incorporating fluid means
 F04B 47/06
·  having motor-pump units situated at great depth
 F04B 47/08
·  ·  the motors being actuated by fluid
 F04B 47/10
·  ·  ·  the units or parts thereof being liftable to ground level by fluid pressure
 F04B 47/12
·  having free plunger lifting the fluid to the surface
 F04B 47/14
·  Counterbalancing
P:230 F04B 49/00
Control of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for in, or of interest apart from, groups F04B 1/00-F04B 47/00
 F04B 49/02
·  Stopping, starting, unloading, or idling control (controlled electrically F04B 49/06)  [6]
 F04B 49/025
·  ·  by means of floats  [6]
 F04B 49/03
·  ·  by means of valves  [6]
 F04B 49/035
·  ·  ·  Bypassing  [6]
 F04B 49/04
·  Regulating by means of floats (F04B 49/025 takes precedence)  [6]
 F04B 49/06
·  Control using electricity (regulating by means of floats actuating electric switches F04B 49/04)
 F04B 49/08
·  Regulating by delivery pressure
 F04B 49/10
·  Other safety measures
 F04B 49/12
·  by varying the length of stroke of the working members  [6]
 F04B 49/14
·  ·  Adjusting abutments located in the path of reciprocation  [6]
 F04B 49/16
·  by adjusting the capacity of dead spaces of working chambers  [6]
 F04B 49/18
·  by changing the effective cross-section of the working surface of the piston  [6]
 F04B 49/20
·  by changing the driving speed (controlled electrically F04B 49/06)  [6]
 F04B 49/22
·  by means of valves (F04B 49/03 takes precedence)  [6]
 F04B 49/24
·  ·  Bypassing  [6]
P:0 F04B 51/00
Testing machines, pumps, or pumping installations
P:240 F04B 53/00
Component parts, details or accessories not provided for in, or of interest apart from, groups F04B 1/00-F04B 23/00 or F04B 39/00-F04B 47/00  [6]
 F04B 53/02
·  Packing the free space between cylinders and pistons  [6]
 F04B 53/04
·  Draining  [6]
 F04B 53/06
·  Venting  [6]
 F04B 53/08
·  Cooling (of machines or engines in general F01P); Heating; Preventing freezing  [6]
 F04B 53/10
·  Valves; Arrangement of valves  [6]
 F04B 53/12
·  ·  arranged in or on pistons  [6]
 F04B 53/14
·  Pistons, piston-rods or piston-rod connections  [6]
 F04B 53/16
·  Casings; Cylinders; Cylinder liners or heads; Fluid connections  [6]
 F04B 53/18
·  Lubricating (of machines or engines in general F01M)  [6]
 F04B 53/20
·  Filtering  [6]
 F04B 53/22
·  Arrangements for enabling ready assembly or disassembly  [6]