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.
recording or playback of information by relative movement between a record track and a transducer, the transducer directly producing, or being directly actuated by, modulation in the track being recorded or played-back, and the extent of modulation corresponding to the signal being recorded or played-back;
apparatus and machines for recording or playback, and parts thereof, such as heads;
record carriers for use with such apparatus and machines;
associated working of other apparatus with such apparatus and machines.
In this subclass, the following terms or expressions are used with the meanings indicated:
"record carrier" means a body, such as a cylinder, disc, card, tape, or wire, capable of permanently holding information, which can be read-off by a sensing element movable relatively to the record carrier; [7]
"head" includes any means for converting sinusoidal or non-sinusoidal electric wave-forms into variations of the physical condition of at least the adjacent surface of the record carrier, or vice versa;
"near-field interaction" means a very short distance interaction using scanning-probe techniques, e.g. quasi- contact or evanescent contact between head and record carrier. [7]
Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor (Fulltext... Hierarchy... Expanded...G11B 11/00 takes precedence) [4]
Structure or manufacture of a head with more than one gap for erasing, recording or reproducing on the same track (Fulltext... Hierarchy... Expanded...G11B 5/33 takes precedence) [4]
G11B 5/29
· ·
Structure or manufacture of unitary devices formed of plural heads for more than one track [4]
Arrangements for functional testing of heads; Measuring arrangements for heads (measuring electric or magnetic properties Fulltext... Hierarchy... Expanded...G01R) [4]
with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following [2]
This group does not cover compositions, materials or processes, per se, which are covered by the relevant subclasses of section B or C. [4]
G11B 5/64
· ·
comprising only the magnetic material without bonding agent
G11B 5/66
· · ·
the record carriers consisting of several layers
G11B 5/68
· ·
comprising one or more layers of magnetisable particles homogeneously mixed with a bonding agent (layered products in general Fulltext... Hierarchy... Expanded...B32B)
with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following [4]
G11B 7/095
· · ·
specially adapted for discs, e.g. for compensation of eccentricity or wobble [4]
G11B 7/10
· ·
Interchangeable mountings, e.g. for replacement of head without readjustment
Dual-recording arrangements, i.e. in which the information is recorded in two different forms simultaneously on the same or related tracks, e.g. recording instantaneous and mean values (sound-recording combined with cinematography Fulltext... Hierarchy... Expanded...G03C)
G11B 7/22
· ·
Apparatus or processes specially adapted for the manufacture of heads, e.g. assembly
Re-recording, i.e. transcribing information from one optical record carrier on to one or more similar or dissimilar record carriers using optical sensing means
Recording simultaneously or selectively by methods or means covered by different main groups; Record carriers therefor; Reproducing simultaneously or selectively therefrom [1,7]
G11B 13/00
Note(s)
This group covers arrangements in which there are at least two recordings of information involving two different methods or means or two different physical properties, at the same or different locations, on the same record carrier, the recordings being made or reproduced simultaneously or selectively. [7]
Manually-operated control; Solenoid-operated control
G11B 15/12
· ·
Masking of heads; Selecting or switching of heads between operative and inoperative functions; Masking of beams, e.g. of light beams
G11B 15/16
· ·
by sensing presence, absence or position of record carrier or container
G11B 15/18
·
Driving; Starting; Stopping; Arrangements for control or regulation thereof
G11B 15/26
· ·
Driving record carriers by members acting directly or indirectly thereon
G11B 15/28
· · ·
through rollers driving by frictional contact with the record carrier, e.g. capstan; Multiple arrangements of capstans or drums coupled to means for controlling the speed of the drive; Multiple capstan systems alternately engageable with record carrier to provide reversal
G11B 15/43
· ·
Control or regulation of mechanical tension of record carrier, e.g. tape tension
G11B 15/44
· ·
Speed-changing arrangements; Reversing arrangements; Drive-transfer means therefor
G11B 15/46
· ·
Controlling, regulating, or indicating speed
G11B 15/467
· · ·
in arrangements for recording or reproducing wherein both record carriers and heads are driven [4]
G11B 15/473
· · · ·
by controlling the speed of the heads [4]
G11B 15/48
· · ·
Starting; Accelerating; Decelerating; Arrangements preventing malfunction during drive change
the magazine having a toroidal or part-toroidal shape
G11B 17/26
· ·
the magazine having a cylindrical shape with vertical axis
G11B 17/28
· ·
the magazine having a cylindrical shape with horizontal axis
G11B 17/30
· ·
wherein the playing unit is moved accordingly to the location of the selected record
G11B 17/32
·
Maintaining desired spacing between record carrier and head, e.g. by fluid-dynamic spacing [2]
P:80
G11B 19/00
Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function (guiding such record carriers Fulltext... Hierarchy... Expanded...G11B 17/00)
G11B 19/02
·
Control of operating function, e.g. switching from recording to reproducing [4]
G11B 19/04
· ·
Arrangements for preventing, inhibiting, or warning against, double recording on the same blank, or against other recording or reproducing malfunctions
Formatting, e.g. arrangement of data block or words on the record carriers [4]
G11B 20/14
· ·
using self-clocking codes [4]
G11B 20/16
· ·
using non self-clocking codes, i.e. the clock signals being either recorded in a separate clocking track or in a combination of several information tracks [4]
G11B 20/18
· ·
Error detection or correction; Testing [4]
G11B 20/20
·
for correction of skew for multitrack recording [4]
G11B 20/22
·
for reducing distortions [4]
G11B 20/24
·
for reducing noise [4]
P:110
G11B 21/00
Head arrangements not specific to the method of recording or reproducing
G11B 21/02
·
Driving or moving of heads
G11B 21/03
· ·
for correcting time base error [4]
G11B 21/04
· ·
Automatic feed mechanism producing a transducing traverse of the head in a direction which cuts across the direction of travel of the recording medium, e.g. helical scan
Raising and lowering; Back-spacing or forward-spacing along track; Returning to starting position
G11B 21/16
·
Supporting the heads; Supporting the sockets for plug-in heads
G11B 21/20
· ·
while the head is in operative position but stationary or permitting minor movements to follow irregularities in surface of record carrier
G11B 21/21
· · ·
with provision for maintaining desired spacing of head from record carrier, e.g. fluid-dynamic spacing, slider [4]
G11B 21/22
· ·
while the head is out of operative position
P:130
G11B 23/00
Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus [4]
Constructional parts, details or accessories not provided for in the other groups of this subclass (containers, packaging elements or packages specially adapted for record carriers Fulltext... Hierarchy... Expanded...B65D 85/00) [4]