G
SECTION G — PHYSICS
 G

Note(s)

  1. 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).
  2. 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 G01 and "control" and "regulation" in class G05.
  3. 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 (G09), for enabling the result of a measurement to be known (G01), for signalling the information to a distant point or for giving information which has been signalled from a distant point (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 (G01L) or about some other condition linked to the pressure (another subclass of class G01, e.g., G01K for temperature), to make a record of the pressure or of its occurrence (G07C), to give an alarm (G08B), or to control another apparatus (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
 G04
HOROLOGY
 G04C
ELECTROMECHANICAL CLOCKS OR WATCHES (mechanical parts of clocks or watches in general G04B; electronic time-pieces with no moving parts, electronic circuitry for producing timing pulses G04G)
 G04C

Note(s)

This subclass covers electric features of mechanically-driven clocks or watches, such as electric winding of such clocks or the provision of electric contacts thereon.

 G04C
Subclass index
ELECTRIC WINDING OF MECHANICAL CLOCKS 1/00
ELECTROMECHANICAL CLOCK MOVEMENTS; ELECTRIC OR MAGNETIC ESCAPEMENTS 3/00, 5/00
TIME INDICATING
Optical; acoustical means 17/00, 19/00; 21/00
TIME SETTING 9/00
POWER SUPPLIES 10/00
SYNCHRONISATION; MASTER-AND-SLAVE CLOCK SYSTEM; SYNCHRONOUS-MOTOR CLOCKS 11/00; 13/00; 15/00
CLOCKS FOR OPERATING A DEVICE AT A PRESELECTED TIME 23/00
SUBJECT MATTER NOT PROVIDED FOR IN OTHER GROUPS OF THIS SUBCLASS 99/00
 G04C 1/00 - 
G04C 10/00
Electric winding of mechanical clocks; Independent electric clocks or watches
P:70 G04C 1/00
Winding mechanical clocks electrically (winding mechanically G04B 3/00)
P:90 G04C 3/00
Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means (clocks driven by synchronous motors G04C 15/00)
P:100 G04C 5/00
Electric or magnetic means for converting oscillatory to rotary motion in time-pieces, i.e. electric or magnetic escapements (regulators G04C 3/00)  [3]
P:30 G04C 9/00
Electrically-actuated devices for setting the time-indicating means (of slave clocks G04C 13/00; mechanical setting devices G04B 27/00)  [3]
P:110 G04C 10/00
Arrangements of electric power supplies in time-pieces  [3]
 G04C 11/00 - 
G04C 15/00
Electric clock installations; Master-and-slave clock systems; Synchronous-motor clocks
P:0 G04C 11/00
Synchronisation of independently-driven clocks
P:10 G04C 13/00
Driving mechanisms for clocks by master clocks
P:80 G04C 15/00
Clocks driven by synchronous motors
 G04C 17/00 - 
G04C 21/00
Indicating the time or producing time signals electrically
P:50 G04C 17/00
Indicating the time optically by electric means (G04C 19/00 takes precedence; liquid crystal materials C09K 19/00; by mechanical means G04B 19/00)  [3]
P:40 G04C 19/00
Producing optical time signals at prefixed times by electric means
P:60 G04C 21/00
Producing acoustic time signals by electrical means
   
P:20 G04C 23/00
Clocks with attached or built-in means operating any device at preselected times or after preselected time-intervals (if restricted to producing acoustic time signals by electrical means G04C 21/00; mechanical alarm clocks G04B 23/00; apparatus which can be set and started to measure-off predetermined intervals G04F 3/00; time or time-programme switches which automatically terminate their operation after the programme is completed H01H 43/00)
P:120 G04C 99/00
Subject matter not provided for in other groups of this subclass  [8]