|  | G |
SECTION G — PHYSICS

|  | G |
Note(s) 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.

INSTRUMENTS

|  | G01 |
MEASURING (counting Fulltext... Hierarchy... Expanded...G06M); TESTING

|  | G01 |
Note(s) This class covers, in addition to "true" measuring instruments, other indicating or recording devices of analogous construction, and also signalling or control devices insofar as they are concerned with measurement (as defined in Note 2 below) and are not specially adapted to the particular purpose of signalling or control. In this class, the following term is used with the meaning indicated: "measuring" is used to cover considerably more than its primary or basic meaning. In this primary sense, it means finding a numerical expression of the value of a variable in relation to a unit or datum or to another variable of the same nature, e.g. expressing a length in terms of another length as in measuring a length with a scale; the value may be obtained directly (as just suggested) or by measuring some other variable of which the value can be related to the value of the required variable, as in measuring a change in temperature by measuring a resultant change in the length of a column of mercury. However, since the same device or instrument may, instead of giving an immediate indication, be used to produce a record or to initiate a signal to produce an indication or control effect, or may be used in combination with other devices or instruments to give a conjoint result from measurement of two or more variables of the same or different kinds, it is necessary to interpret "measuring" as including also any operation that would make it possible to obtain such a numerical expression by the additional use of some way of converting a value into figures. Thus the expression in figures may be actually made by a digital presentation or by reading a scale, or an indication of it may be given without the use of figures, e.g. by some perceptible feature (variable) of the entity (e.g. object, substance, beam of light) of which the variable being measured is a property or condition or by an analogue of such a feature (e.g. the corresponding position of a member without any scale, a corresponding voltage generated in some way). In many cases there is no such value indication but only an indication of difference or equality in relation to a standard or datum (of which the value may or may not be known in figures); the standard or datum may be the value of another variable of the same nature but of a different entity (e.g. a standard measure) or of the same entity at a different time. In its simplest form, measurement may give merely an indication of presence or absence of a certain condition or quality, e.g. movement (in any direction or in a particular direction), or whether a variable exceeds a predetermined value. Attention is drawn to the Notes following the title of section G, especially as regards the definition of the term "variable". In many measuring arrangements, a first variable to be measured is transformed into a second, or further, variables. The second, or further, variables may be (a) a condition related to the first variable and produced in a member, or (b) a displacement of a member. Further transformation may be needed. [6] When classifying such an arrangement, (i) the transformation step, or each transformation step, that is of interest is classified, or (ii) if interest lies only in the system as a whole, the first variable is classified in the appropriate place. [6] This is particularly important where two or more conversions take place, for instance where a first variable, for example pressure, is transformed into a second variable, for example an optical property of a sensing body, and that second variable is expressed by means of a third variable, for example an electric effect. In such a case, the following classification places should be considered: the place for the transformation of the first variable, that for sensing the condition caused by that variable, subclass Fulltext... Hierarchy... Expanded...G01D for expression of the measurement, and finally the place for the overall system, if any. [6] The measurement of change in the value of a physical property is classified in the same subclass as the measurement of that physical property, e.g. measurement of expansion of length is classified in subclass Fulltext... Hierarchy... Expanded...G01B.

|  | G01D |
MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED BY A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR (means structurally associated with lightning or other overvoltage discharging apparatus for recording the operation thereof Fulltext... Hierarchy... Expanded...G01R; displaying information in general Fulltext... Hierarchy... Expanded...G09F; recording in a way which requires playback through a transducer Fulltext... Hierarchy... Expanded...G11B)

|  | G01D |
Note(s) This subclass covers: devices for indicating or recording the results of measurements, not peculiar to variables covered by a single other subclass; analogous arrangements but in which the input is not a variable to be measured, e.g. a hand operation; details of measuring instruments, which are of general interest; measurement transducers not adapted solely for the measurement of a single specified variable and not provided for elsewhere, i.e. means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; measuring or testing not otherwise provided for. Attention is drawn to the Notes following the title of class Fulltext... Hierarchy... Expanded...G01.

|  | G01D |
Subclass index
MEASURING ARRANGEMENTS IN GENERAL |
With data restitution in other form than their instantaneous value | 1/00
With provision for special purposes | 3/00
Transferring and converting arrangements, prevailing means used | 5/00
Component parts | 11/00
INDICATING; COMPONENT PARTS OF INDICATORS | 7/00, 13/00
RECORDING; COMPONENT PARTS OF RECORDERS | 9/00, 15/00
TESTING OR CALIBRATING | 18/00
MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR | 21/00
TARIFF METERING | 4/00

|  | G01D 1/00 |
Measuring arrangements giving results other than momentary value of variable, of general application (Fulltext... Hierarchy... Expanded...G01D 3/00 takes precedence; in tariff metering apparatus Fulltext... Hierarchy... Expanded...G01D 4/00; transducers not specially adapted for a specific variable Fulltext... Hierarchy... Expanded...G01D 5/00; computing Fulltext... Hierarchy... Expanded...G06)

|  | G01D 1/02 |
· | giving mean values, e.g. root mean square values (measuring root mean square values of currents or voltages Fulltext... Hierarchy... Expanded...G01R 19/02)

|  | G01D 1/04 |
· | giving integrated values (giving mean values Fulltext... Hierarchy... Expanded...G01D 1/02)

|  | G01D 1/06 |
· · | by intermittent summation

|  | G01D 1/08 |
· · · | over fixed periods of time

|  | G01D 1/10 |
· | giving differentiated values

|  | G01D 1/12 |
· | giving a maximum or minimum of a value

|  | G01D 1/14 |
· | giving a distribution function of a value, i.e. number of times the value comes within specified ranges of amplitude

|  | G01D 1/16 |
· | giving a value which is a function of two or more values, e.g. product, ratio

|  | G01D 1/18 |
· | with arrangements for signalling that a predetermined value of an unspecified parameter has been exceeded (Fulltext... Hierarchy... Expanded...G01D 1/14 takes precedence; for a specified parameter, see the subclass relevant to this parameter, e.g. level of a liquid exceeded Fulltext... Hierarchy... Expanded...G01F, temperature exceeded Fulltext... Hierarchy... Expanded...G01K) [3]

|  | G01D 3/00 |
Measuring arrangements with provision for the special purposes referred to in the subgroups of this group

|  | G01D 3/02 |
· | with provision for altering or correcting the transfer function

|  | G01D 3/024 |
· · | for range change; Arrangements for substituting one sensing member by another [6]

|  | G01D 3/028 |
· | mitigating undesired influences, e.g. temperature, pressure [6]

|  | G01D 3/032 |
· · | affecting incoming signal, e.g. by averaging; gating undesired signals [6]

|  | G01D 3/036 |
· · | on measuring arrangements themselves [6]

|  | G01D 3/04 |
( transferred to Fulltext... Hierarchy... Expanded...G01D 3/028 )

|  | G01D 3/06 |
· | with provision for operation by a null method

|  | G01D 3/08 |
· | with provision for safeguarding the apparatus, e.g. against abnormal operation, against breakdown

|  | G01D 3/10 |
· | with provision for switching-in of additional or auxiliary indicators or recorders

|  | G01D 4/00 |
Tariff metering apparatus (tariff meters for measuring the time integral of electric power or current Fulltext... Hierarchy... Expanded...G01R 11/56; in taximeters Fulltext... Hierarchy... Expanded...G07B 13/00; coin-freed mechanisms therefor Fulltext... Hierarchy... Expanded...G07F)

|  | G01D 4/02 |
· | Details

|  | G01D 4/04 |
· · | Resetting-mechanisms, e.g. for indicating members (for mechanical counters Fulltext... Hierarchy... Expanded...G06M 1/28)

|  | G01D 4/06 |
· · | Arrangement of clutches between driving and indicating member, e.g. of hysteresis clutch (Fulltext... Hierarchy... Expanded...G01D 4/04 takes precedence)

|  | G01D 4/08 |
· · | Transfer of indication from a counter into a summing counter (mechanical counters Fulltext... Hierarchy... Expanded...G06M)

|  | G01D 4/10 |
· | Maximum indicating or recording apparatus, i.e. where the tariff for a period is based on a maximum demand within that period

|  | G01D 4/12 |
· · | Apparatus for indicating or recording progressive maximum

|  | G01D 4/14 |
· · | Fixed-demand indicating or recording apparatus, i.e. where indication is made when a predetermined quantity has been consumed during a time interval greater or less than a predetermined time interval

|  | G01D 4/16 |
· | Apparatus for indicating or recording maximum or minimum load hours

|  | G01D 4/18 |
· | Apparatus for indicating or recording overconsumption with opposing torque which comes into effect when a predetermined level is exceeded, e.g. subtraction meters

|  | G01D 5/00 |
Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable (Fulltext... Hierarchy... Expanded...G01D 3/00 takes precedence; specially adapted for apparatus giving results other than momentary value of variable Fulltext... Hierarchy... Expanded...G01D 1/00; sensing members, see the relevant subclasses, e.g. of Fulltext... Hierarchy... Expanded...G01, Fulltext... Hierarchy... Expanded...H01; for converting a single current or a single voltage into a mechanical displacement Fulltext... Hierarchy... Expanded...G01R 5/00; specially adapted for high-voltage or high-current measuring arrangements Fulltext... Hierarchy... Expanded...G01R 15/04, Fulltext... Hierarchy... Expanded...G01R 15/14; measuring currents or voltages using digital measurement techniques Fulltext... Hierarchy... Expanded...G01R 19/25; transmission systems for measured values, control or similar signals Fulltext... Hierarchy... Expanded...G08C, e.g. electrical signals Fulltext... Hierarchy... Expanded...G08C 19/00) [6]

|  | G01D 5/00 |
Note(s) The subgroups of this main group are distinguished by the means which is of major importance. Thus the mere application of other means for giving a final indication does not affect the classification.

|  | G01D 5/02 |
· | using mechanical means

|  | G01D 5/04 |
· · | using levers; using cams; using gearing (gearing in general Fulltext... Hierarchy... Expanded...F16)

|  | G01D 5/06 |
· · | acting through a wall or enclosure, e.g. by bellows, by magnetic coupling (in general Fulltext... Hierarchy... Expanded...F16)

|  | G01D 5/08 |
· · | Reducing the effects of friction, e.g. by applying vibrations

|  | G01D 5/10 |
· · | Applying external forces to increase force available for operation of indicating or recording part

|  | G01D 5/12 |
· | using electric or magnetic means (Fulltext... Hierarchy... Expanded...G01D 5/06 takes precedence) [3]

|  | G01D 5/14 |
· · | influencing the magnitude of a current or voltage

|  | G01D 5/16 |
· · · | by varying resistance

|  | G01D 5/165 |
· · · · | by relative movement of a point of contact and a resistive track [6]

|  | G01D 5/18 |
· · · | by varying effective impedance of discharge tubes or semiconductor devices

|  | G01D 5/20 |
· · · | by varying inductance, e.g. by a movable armature

|  | G01D 5/22 |
· · · · | differentially influencing two coils

|  | G01D 5/24 |
· · · | by varying capacitance

|  | G01D 5/241 |
· · · · | by relative movement of capacitor electrodes [6]

|  | G01D 5/242 |
· · · | by varying output of an electrodynamic device, e.g. of a tachodynamo

|  | G01D 5/243 |
· · | influencing the phase or frequency of ac

|  | G01D 5/244 |
· · | influencing characteristics of pulses or pulse trains; generating pulses or pulse trains [6]

|  | G01D 5/245 |
· · · | using a variable number of pulses in a train

|  | G01D 5/246 |
· · · | by varying the duration of individual pulses

|  | G01D 5/247 |
· · · | using time shifts of pulses

|  | G01D 5/248 |
· · · | by varying pulse repetition frequency

|  | G01D 5/249 |
· · · | using pulse code

|  | G01D 5/25 |
· · | Selecting one or more conductors or channels from a plurality of conductors or channels, e.g. by closing contacts

|  | G01D 5/251 |
· · · | one conductor or channel

|  | G01D 5/252 |
· · · | a combination of conductors or channels

|  | G01D 5/26 |
· | using optical means, i.e. using infra-red, visible or ultra-violet light

|  | G01D 5/28 |
· · | with deflection of beams of light, e.g. for direct optical indication (Fulltext... Hierarchy... Expanded...G01D 5/40 takes precedence)

|  | G01D 5/30 |
· · · | the beams of light being detected by photocells

|  | G01D 5/32 |
· · | with attenuation or whole or partial obturation of beams of light (Fulltext... Hierarchy... Expanded...G01D 5/40 takes precedence)

|  | G01D 5/34 |
· · · | the beams of light being detected by photocells

|  | G01D 5/347 |
· · · · | using displacement encoding scales [6]

|  | G01D 5/353 |
· · · · | influencing the transmission properties of an optical fibre [6]

|  | G01D 5/36 |
· · · · | Forming the light into pulses

|  | G01D 5/38 |
· · · · · | by diffraction gratings

|  | G01D 5/39 |
· · | Scanning a visible indication of the measured value and reproducing this indication at a remote place, e.g. on the screen of a cathode-ray tube

|  | G01D 5/40 |
· · | specially adapted for use with infra-red light

|  | G01D 5/42 |
· | using fluid means

|  | G01D 5/44 |
· · | using jets of fluid

|  | G01D 5/46 |
· · · | by deflecting or throttling the flow

|  | G01D 5/48 |
· | using wave or particle radiation means (Fulltext... Hierarchy... Expanded...G01D 5/26 takes precedence)

|  | G01D 5/50 |
· · | derived from a radioactive source

|  | G01D 5/52 |
· · · | detected by a counter tube

|  | G01D 5/54 |
· | using means specified in two or more of groups Fulltext... Hierarchy... Expanded...G01D 5/02, Fulltext... Hierarchy... Expanded...G01D 5/12, Fulltext... Hierarchy... Expanded...G01D 5/26, Fulltext... Hierarchy... Expanded...G01D 5/42, and Fulltext... Hierarchy... Expanded...G01D 5/48

|  | G01D 5/54 |
Note(s) For a combination of two or more of the means specified, the first applicable one of the subgroups below takes precedence over any others of these groups. Classification is made in this group only if no other group can be selected as being predominantly applicable.

|  | G01D 5/56 |
· · | using electric or magnetic means

|  | G01D 5/58 |
· · | using optical means, i.e. using infra-red, visible or ultra-violet light

|  | G01D 5/60 |
· · | using fluid means

|  | G01D 5/62 |
· · | using wave or particle radiation means not covered by group Fulltext... Hierarchy... Expanded...G01D 5/58

|  | G01D 7/00 |
Indicating measured values

|  | G01D 7/02 |
· | Indicating value of two or more variables simultaneously

|  | G01D 7/04 |
· · | using a separate indicating element for each variable

|  | G01D 7/06 |
· · · | Luminous indications projected on a common screen

|  | G01D 7/08 |
· · | using a common indicating element for two or more variables

|  | G01D 7/10 |
· · · | giving indication in co-ordinate form

|  | G01D 7/12 |
· | Audible indication of meter readings, e.g. for the blind [2]

|  | G01D 9/00 |
Recording measured values

|  | G01D 9/02 |
· | Producing one or more recordings of the values of a single variable

|  | G01D 9/04 |
· · | with provision for multiple or alternative recording

|  | G01D 9/06 |
· · · | Multiple recording, e.g. duplicating

|  | G01D 9/08 |
· · · · | giving both graphical and numerical recording

|  | G01D 9/10 |
· · | the recording element, e.g. stylus, being controlled in accordance with the variable, and the recording medium, e.g. paper roll, being controlled in accordance with time

|  | G01D 9/12 |
· · · | recording occurring continuously

|  | G01D 9/14 |
· · · · | with provision for altering speed of recording medium in accordance with the magnitude of the variable to be recorded

|  | G01D 9/16 |
· · · | recording occurring at separated intervals, e.g. by chopper bar

|  | G01D 9/18 |
· · · · | recording element actuated only upon change in value of variable

|  | G01D 9/20 |
· · | the recording element, e.g. stylus, being controlled in accordance with time and the recording medium, e.g. paper roll, being controlled in accordance with the variable

|  | G01D 9/22 |
· · · | recording occurring continuously

|  | G01D 9/24 |
· · · | recording occurring at separated intervals, e.g. by chopper bar

|  | G01D 9/26 |
· · | either the recording element, e.g. stylus, or the recording medium, e.g. paper roll, being controlled in accordance with both time and the variable

|  | G01D 9/28 |
· | Producing one or more recordings, each recording being of the values of two or more different variables (Fulltext... Hierarchy... Expanded...G01D 9/38, Fulltext... Hierarchy... Expanded...G01D 9/40 take precedence)

|  | G01D 9/30 |
· · | there being a separate recording element for each variable, e.g. multiple-pen recorder

|  | G01D 9/32 |
· · | there being a common recording element for two or more variables

|  | G01D 9/34 |
· · · | the variables being recorded in predetermined sequence

|  | G01D 9/36 |
· · · · | in separate columns

|  | G01D 9/38 |
· | Producing one or more recordings, each recording being produced by controlling the recording element, e.g. stylus, in accordance with one variable and controlling the recording medium, e.g. paper roll, in accordance with another variable

|  | G01D 9/40 |
· | Producing one or more recordings, each recording being produced by controlling either the recording element, e.g. stylus, or the recording medium, e.g. paper roll, in accordance with two or more variables

|  | G01D 9/42 |
· | Recording indications of measuring instruments by photographic means, e.g. of counters

|  | G01D 11/00 |
Component parts of measuring arrangements not specially adapted for a specific variable (Fulltext... Hierarchy... Expanded...G01D 13/00, Fulltext... Hierarchy... Expanded...G01D 15/00 take precedence)

|  | G01D 11/02 |
· | Bearings or suspensions for moving parts (bearings in general Fulltext... Hierarchy... Expanded...F16C)

|  | G01D 11/04 |
· · | Knive-edge bearings

|  | G01D 11/06 |
· · | Strip or thread suspensions, e.g. in tension

|  | G01D 11/08 |
· | Elements for balancing moving parts

|  | G01D 11/10 |
· | Elements for damping the movement of parts

|  | G01D 11/12 |
· · | using fluid damping

|  | G01D 11/14 |
· · | using magnetic induction damping

|  | G01D 11/16 |
· | Elements for restraining or preventing the movement of parts, e.g. for zeroising (caging of moving parts when not in use Fulltext... Hierarchy... Expanded...G01D 11/20)

|  | G01D 11/18 |
· · | Springs (Fulltext... Hierarchy... Expanded...G01D 11/06 takes precedence)

|  | G01D 11/20 |
· | Caging devices for moving parts when not in use

|  | G01D 11/22 |
· · | automatically actuated

|  | G01D 11/24 |
· | Housings

|  | G01D 11/26 |
· · | Windows; Cover glasses; Sealings therefor

|  | G01D 11/28 |
· | Structurally-combined illuminating devices

|  | G01D 11/30 |
· | Supports specially adapted for an instrument; Supports specially adapted for a set of instruments (in general Fulltext... Hierarchy... Expanded...F16M; specially adapted for aircraft or vehicles, see the relevant subclasses)

|  | G01D 13/00 |
Component parts of indicators for measuring arrangements not specially adapted for a specific variable

|  | G01D 13/02 |
· | Scales; Dials

|  | G01D 13/04 |
· · | Construction

|  | G01D 13/06 |
· · · | Moving bands (Fulltext... Hierarchy... Expanded...G01D 13/10 takes precedence)

|  | G01D 13/08 |
· · · | Rotating drums (Fulltext... Hierarchy... Expanded...G01D 13/10 takes precedence)

|  | G01D 13/10 |
· · · | with adjustable scales; with auxiliary scales, e.g. vernier

|  | G01D 13/12 |
· · | Graduation

|  | G01D 13/14 |
· · · | for rotations of more than 360°

|  | G01D 13/16 |
· · · | with staggered markings

|  | G01D 13/18 |
· · · | with raised or recessed markings

|  | G01D 13/20 |
· · · | with luminescent markings

|  | G01D 13/22 |
· | Pointers, e.g. settable pointer

|  | G01D 13/24 |
· · | for indicating a maximum or minimum

|  | G01D 13/26 |
· · | adapted to perform a further operation, e.g. making electrical contact

|  | G01D 13/28 |
· · | with luminescent markings

|  | G01D 15/00 |
Component parts of recorders for measuring arrangements not specially adapted for a specific variable

|  | G01D 15/02 |
· | Styli or other recording elements acting to mechanically deform or perforate the recording surface (printing recording elements Fulltext... Hierarchy... Expanded...G01D 15/20)

|  | G01D 15/04 |
· · | acting to punch holes in the recording surface

|  | G01D 15/06 |
· | Electric recording elements, e.g. electrolytic

|  | G01D 15/08 |
· · | for spark erosion

|  | G01D 15/10 |
· | Heated recording elements acting on heat-sensitive layers

|  | G01D 15/12 |
· | Magnetic recording elements

|  | G01D 15/14 |
· | Optical recording elements; Recording elements using X- or nuclear radiation

|  | G01D 15/16 |
· | Recording elements transferring recording material, e.g. ink, to the recording surface (printing recording elements Fulltext... Hierarchy... Expanded...G01D 15/20; implements for writing or drawing in general Fulltext... Hierarchy... Expanded...B43K)

|  | G01D 15/18 |
· · | Nozzles emitting recording material

|  | G01D 15/20 |
· | Recording elements for printing with ink or for printing by deformation or perforation of the recording surface, e.g. embossing

|  | G01D 15/22 |
· | Chopper bars for bringing recording element into contact with recording surface

|  | G01D 15/24 |
· | Drives for recording elements or surfaces, not covered by group Fulltext... Hierarchy... Expanded...G01D 5/00

|  | G01D 15/26 |
· · | operating by clockwork (clockworks per se Fulltext... Hierarchy... Expanded...G04B, Fulltext... Hierarchy... Expanded...G04C)

|  | G01D 15/28 |
· | Holding means for recording surfaces; Guiding means for recording surfaces; Exchanging means for recording surfaces

|  | G01D 15/30 |
· · | for foldable strip charts

|  | G01D 15/32 |
· · | for circular charts

|  | G01D 15/34 |
· | Recording surfaces

|  | G01D 18/00 |
Testing or calibrating of apparatus or arrangements provided for in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...G01D 1/00-G01D 15/00

|  | G01D 21/00 |
Measuring or testing not otherwise provided for

|  | G01D 21/02 |
· | Measuring two or more variables by means not covered by a single other subclass