In this section, the following term is used with the meaning indicated:
"variable" (as a noun) means a feature or property (e.g., a dimension, a physical condition such as temperature, a quality such as density or colour) which, in respect of a particular entity (e.g., an object, a quantity of a substance, a beam of light) and at a particular instant, is capable of being measured; the variable may change, so that its numerical expression may assume different values at different times, in different conditions or in individual cases, but may be constant in respect of a particular entity in certain conditions or for practical purposes (e.g., the length of a bar may be regarded as constant for many purposes).
Attention is drawn to the definitions of terms or expressions used, appearing in the notes of several of the classes in this section, in particular those of "measuring" in class Fulltext... Hierarchy... Expanded...G01 and "control" and "regulation" in class Fulltext... Hierarchy... Expanded...G05.
Classification in this section may present more difficulty than in other sections, because the distinction between different fields of use rests to a considerable extent on differences in the intention of the user rather than on any constructional differences or differences in the manner of use, and because the subjects dealt with are often in effect systems or combinations, which have features or parts in common, rather than "things", which are readily distinguishable as a whole. For example, information (e.g., a set of figures) may be displayed for the purpose of education or advertising (Fulltext... Hierarchy... Expanded...G09), for enabling the result of a measurement to be known (Fulltext... Hierarchy... Expanded...G01), for signalling the information to a distant point or for giving information which has been signalled from a distant point (Fulltext... Hierarchy... Expanded...G08). The words used to describe the purpose depend on features that may be irrelevant to the form of the apparatus concerned, for example, such features as the desired effect on the person who sees the display, or whether the display is controlled from a remote point. Again, a device which responds to some change in a condition, e.g., in the pressure of a fluid, may be used, without modification of the device itself, to give information about the pressure (Fulltext... Hierarchy... Expanded...G01L) or about some other condition linked to the pressure (another subclass of class Fulltext... Hierarchy... Expanded...G01, e.g., Fulltext... Hierarchy... Expanded...G01K for temperature), to make a record of the pressure or of its occurrence (Fulltext... Hierarchy... Expanded...G07C), to give an alarm (Fulltext... Hierarchy... Expanded...G08B), or to control another apparatus (Fulltext... Hierarchy... Expanded...G05).
The classification scheme is intended to enable things of a similar nature (as indicated above) to be classified together. It is therefore particularly necessary for the real nature of any technical subject to be decided before it can be properly classified.
This class covers methods, systems, and apparatus for controlling, in general.
In this class, the following terms or expressions are used with the meanings indicated:
"controlling" means influencing a variable in any way, e.g. changing its direction or its value (including changing it to or from zero), maintaining it constant, limiting its range of variation;
"regulation" means maintaining a variable automatically at a desired value or within a desired range of values. The desired value or range may be fixed, or manually varied, or may vary with time according to a predetermined "programme" or according to variation of another variable. Regulation is a form of control;
"automatic control" is often used in the art as a synonym for "regulation".
Attention is drawn to the Notes following the title of section G, especially as regards the definition of the term "variable".
This subclass does not cover features of general applicability to regulating systems, e.g. anti-hunting arrangements, which are covered by subclass Fulltext... Hierarchy... Expanded...G05B.
In this subclass, the following term is used with the meaning indicated:
"systems" includes self-contained devices such as speed governors, pressure regulators.
Control systems specially adapted for particular apparatus, machines or processes are classified in the subclasses for the apparatus, machines or processes, provided that there is specific provision for control or regulation relevant to the special adaptation, either at a detailed level (e.g. Fulltext... Hierarchy... Expanded...A21B 1/40: "for regulating temperature in bakers' ovens") or at a general level (e.g. Fulltext... Hierarchy... Expanded...B23K 9/095: "for automatic control of welding parameters in arc welding"). Otherwise, classification is made in the most appropriate place in this subclass.
The following are lists of places where there is specific provision of the kind referred to above. Where such provision is at a detailed level, the places have been grouped according to the main groups of this subclass. Where the provision is at a general level (e.g. of a kind appropriate to more than one of the main groups specified in the lists, or to main groups Fulltext... Hierarchy... Expanded...G05D 27/00 or Fulltext... Hierarchy... Expanded...G05D 29/00), the places are listed under the title "General References".
Control of position, course, altitude, or attitude of land, water, air, or space vehicles, e.g. automatic pilot (radio navigation systems or analogous systems using other waves Fulltext... Hierarchy... Expanded...G01S)
G05D 1/02
·
Control of position or course in two dimensions [2]
G05D 1/03
· ·
using near-field transmission systems, e.g. inductive-loop type
G05D 1/04
·
Control of altitude or depth
G05D 1/06
· ·
Rate of change of altitude or depth
G05D 1/08
·
Control of attitude, i.e. control of roll, pitch, or yaw
Controlling ratio of two or more flows of fluid or fluent material
G05D 11/03
· ·
without auxiliary power
G05D 11/035
· ·
with auxiliary non-electric power [2]
G05D 11/04
· · ·
by sensing weight of individual components, e.g. gravimetric procedure
G05D 11/06
· · ·
by sensing density of mixture, e.g. using aerometer
G05D 11/08
· · ·
by sensing concentration of mixture, e.g. by measuring pH-value [3]
G05D 11/10
· · · ·
by sensing moisture of non-aqueous liquids
G05D 11/12
· · ·
by sensing viscosity of mixture
G05D 11/13
· ·
characterised by the use of electric means
G05D 11/16
·
Controlling mixing ratio of fluids having different temperatures, e.g. by sensing the temperature of a mixture of fluids having different viscosities
G05D 13/00
Control of linear speed; Control of angular speed; Control of acceleration or deceleration, e.g. of a prime mover (synchronising telegraph receiver and transmitter Fulltext... Hierarchy... Expanded...H04L 7/00)
G05D 13/02
·
Details
G05D 13/04
· ·
providing for emergency tripping of an engine in case of exceeding maximum speed
G05D 13/06
· ·
providing for damping of erratic vibrations in governors
G05D 13/08
·
without auxiliary power
G05D 13/10
· ·
Centrifugal governors with fly-weights
G05D 13/12
· · ·
Details
G05D 13/14
· · · ·
Fly-weights; Mountings thereof; Adjusting equipment for limits, e.g. temporarily
counterbalanced by spider springs acting immediately upon the fly-weights
G05D 13/20
· · ·
counterbalanced by spider springs acting upon the articulated riser
G05D 13/22
· · ·
counterbalanced by fluid pressure acting upon the articulated riser
G05D 13/24
· · ·
counterbalanced by two or more different appliances acting simultaneously upon the riser, e.g. with both spring force and fluid pressure, with both spring force and electromagnetic force
G05D 13/26
· · ·
with provision for modulating the degree of non-uniformity of speed
G05D 13/28
· · ·
with provision for performing braking effects in case of increased speed
G05D 13/30
· ·
Governors characterised by fluid features in which the speed of a shaft is converted into fluid pressure (transducers converting variations of physical quantities into fluid-pressure variations Fulltext... Hierarchy... Expanded...F15B 5/00)
using regulating devices with proportional band, i.e. P. regulating devices
G05D 13/38
· · ·
involving centrifugal governors of fly-weight type
G05D 13/40
· · ·
involving centrifugal governors of pump type
G05D 13/42
· · ·
involving fluid governors of flow-controller type, i.e. the width of liquid flow being controlled by fly-weights
G05D 13/44
· · ·
involving fluid governors of jet type
G05D 13/46
· ·
using regulating devices with proportional band and integral action, i.e. P.I. regulating devices
G05D 13/48
· · ·
involving resilient restoring mechanisms
G05D 13/50
· · ·
involving connecting means for superimposing a proportional regulating device and an integral regulating device
G05D 13/52
· ·
using regulating devices with proportional band and derivative action, i.e. P.D. regulating devices
G05D 13/54
· · ·
involving centrifugal governors of fly-weight type exerting an acceleratory effect
G05D 13/56
· · ·
involving restoring mechanisms exerting a delay effect
G05D 13/58
· · ·
involving means for connecting a speed- regulating device and an acceleration- regulating device
G05D 13/60
· ·
using regulating devices with proportional band, derivative, and integral action, i.e. P.I.D. regulating devices
G05D 13/62
·
characterised by the use of electric means, e.g. use of a tachometric dynamo, use of a transducer converting an electric value into a displacement
G05D 13/64
·
Compensating the speed difference between engines meshing by a differential gearing or the speed difference between a controlling shaft and a controlled shaft
G05D 13/66
·
Governor units providing for co-operation with control dependent upon a variable other than speed
G05D 15/00
Control of mechanical force or stress; Control of mechanical pressure
G05D 15/01
·
characterised by the use of electric means
G05D 16/00
Control of fluid pressure
G05D 16/02
·
Modifications to reduce the effects of instability, e.g. due to vibrations, friction, abnormal temperature, overloading, unbalance (vibration-dampers Fulltext... Hierarchy... Expanded...F16F 7/00)
G05D 16/04
·
without auxiliary power
G05D 16/06
· ·
the sensing element being a flexible member yielding to pressure, e.g. diaphragm, bellows, capsule
G05D 16/08
· · ·
Control of liquid pressure
G05D 16/10
· ·
the sensing element being a piston or plunger
G05D 16/12
· ·
the sensing element being a float
G05D 16/14
·
with auxiliary non-electric power [2]
G05D 16/16
· ·
derived from the controlled fluid
G05D 16/18
· ·
derived from an external source
G05D 16/20
·
characterised by the use of electric means
G05D 17/00
Control of torque; Control of mechanical power
G05D 17/02
·
characterised by the use of electric means
G05D 19/00
Control of mechanical oscillations, e.g. of amplitude, of frequency, of phase
G05D 19/02
·
characterised by the use of electric means
G05D 21/00
Control of chemical or physico-chemical variables, e.g. pH-value [3]
the sensing element having a resistance varying with temperature, e.g. thermistor
G05D 23/26
· · ·
the sensing element having a permeability varying with temperature
G05D 23/27
· ·
with sensing element responsive to radiation
G05D 23/275
· ·
with sensing element expanding, contracting, or fusing in response to changes of temperature
G05D 23/30
· ·
Automatic controllers with an auxiliary heating device affecting the sensing element, e.g. for anticipating change of temperature (automatic controllers in general and not restricted to control of temperature Fulltext... Hierarchy... Expanded...G05B)
G05D 23/32
· · ·
with provision for adjustment of the effect of the auxiliary heating device, e.g. as a function of time
G05D 24/00
Control of viscosity
G05D 24/02
·
characterised by the use of electric means
G05D 25/00
Control of light, e.g. intensity, colour, phase (mechanically operable parts of lighting devices for the control of light Fulltext... Hierarchy... Expanded...F21V; optical devices or arrangements using movable or deformable elements for controlling light independent of the light source Fulltext... Hierarchy... Expanded...G02B 26/00; devices or arrangements, the optical operation of which is modified by changing the optical properties of the medium of the devices or arrangements for the control of light, circuit arrangements specially adapted therefor, control of light by electro-magnetic waves, electrons or other elementary particles Fulltext... Hierarchy... Expanded...G02F 1/00) [4]
G05D 25/02
·
characterised by the use of electric means
G05D 27/00
Simultaneous control of variables covered by two or more of the preceding main groups
G05D 27/02
·
characterised by the use of electric means
G05D 29/00
Simultaneous control of electric and non-electric variables