Note(s)

• This class covers:
  • operations not provided for in any other class;
  • combinations of operations covered by different subclasses of classes B21-B24, which combinations are covered by subclass B23P, with the exception of subsidiary operations performed in conjunction with main operations covered by a single subclass;
  • features, specific to machine tools, which relate to a requirement or problem of a nature which is not peculiar to a particular kind of machine tool, e.g. feeding work, which are covered by subclass B23Q, although the realisation of these features may differ according to the kind of machine tool concerned. The said subclass covers such features, in general, even if the feature or a specific function, in any particular case, is to some extent peculiar to, or is claimed only for, machine tools designed for one particular operation; only in exceptional cases are such features classified in the subclass for the machine tool concerned. Certain features of this general nature are, however, referred to subclasses relating to particular metal-working operations, especially B23B, in which case the subclasses in question are not restricted, in respect of those features, to the kind of machine tool with which they are primarily concerned.
• In this class, the following terms or expressions are used with the meanings indicated:
  • "metal-working" covers the working of other materials unless the context requires otherwise;
  • "kind of operations" and similar expressions relate to such metal-working operations as boring, drilling, milling and grinding;
  • "kind of machine" means a machine designed for a particular kind of metal-working operation (e.g. a lathe);
  • "form of machine" means a machine of a particular kind adapted or arranged for a particular way of working or for particular work, e.g. face-plate lathe, tailstock lathe, turret lathe;
  • "different machines" covers different forms of machines for performing the same type of metal-working operation, e.g. vertical and horizontal boring machines.
• If details, components, or accessories have no essential feature specific to machine tools, the more general class, e.g. F16, takes precedence.

Note(s)

• This subclass covers:
  • the use of methods or apparatus specially designed to produce accurately the shapes of gear teeth which are essential for proper intermeshing of toothed gearing elements to ensure the required relative motions;
  • the use of similar methods or apparatus in the production of other articles of toothed or like form, e.g. dog clutches, splined shafts, milling cutters.
• This subclass does not cover the production of such other articles of toothed or like form using methods or apparatus other than those mentioned under Note (1) above.
• In this subclass, the following terms or expressions are used with the meanings indicated:
  • "gear teeth" covers the teeth or lobes of other accurately-intermeshing members having relative movement of a similar kind, such as rotors of rotary pumps and blowers;
  • "profile" may include the outline of both faces or only one face of a tooth, or the opposing faces of adjacent teeth;
  • "straight" means that a tooth as a whole (ignoring any curvature of the tooth-face alone, e.g. crowning) is straight in the direction of its length, for example as seen in the direction of a radius of a spur wheel. It accordingly includes the teeth of helical gears and of the normal type of bevel gear;
  • "broach-milling" means milling with a rotary cutter having a number of teeth of progressively increasing depth or width.