| | This subclass is indented under the class definition. Apparatus or method (1) employing a multitoothed cutting
tool characterized in that: (a) the functional edges of the tool
teeth are so related to one another that the tip of one tooth extends
further than that of an adjacent tooth from a datum line interior
to the tool and paralleling the path of relative movement of tool
and work (which extent is measured along the normal to such datum
line through the tip); and (b) the differences in such extent between
adjacent teeth are progressive from tooth to tooth (or group of
teeth to group of teeth) along such path of relative movement, resulting
in a stair-step arrangement of teeth (or groups of teeth) along
such path and relative to the datum line of reference; and (2) in
whose operation or performance the teeth succesively engage the work
in substantially overlying paths, each tooth removing a predetermined
amount of material so that the work modification produced is congruent
to the last acting tooth.
| | (1)
Note. Illustrative broach tools are shown in the accompanying
drawings. (See accompanying drawings below).
|
| | (2)
Note. In the case of rotary tool motion, it will be noted
that the normal to the datum line (referred to in the definition) is
the radius extending through the tooth tip. |
| | (3)
Note. As indicated by the parenthetical material in part
(1,b) of the above definition, the progressive extent of differences
between the tips (or outer cutting edges) and the datum line is
intended to include a tool comprising a plurality of groups or units
of several teeth each, the tooth elements of each group having the same
extent from the datum line and extending further therefrom than
the tooth elements of the next preceding group, so as to form a
stair-step arrangement of such groups. |
| | (4)
Note. A patent directed to a tool having a unit of tooth
elements of uniform characteristic (such as described in (3) Note, above)
but intended to perform another function (such as scraping or burnishing) will
be found in the class relating to such other function(s). |
| | (5)
Note. Included in this specific subclass, as at least a cross-reference
copy, will be a patent claiming significant machine frame structure.
Patents of this character are generally directed to adjustability
of frame means for convertibility of the machine from or to a vertical
or horizontal operation or for a push or pull operation, or to frame
structure adapted to accentuate accessibility to machine parts,
or to means for transferring broaching tool thrust to the machine
bed. |
| | (6)
Note. A patent wherein the work feed system imparts energy
to the work support so as to absorb contemplated broach thrust will
be found in subclass 269 below; an example of such will be a crank
pin which positions a work table at the dead center position of
such crank pin but wherein the drive force actuating the crank is
above that necessary to obtain said dead center position. |
| | (7)
Note. A single-edged cutter device for shaping work, though
described as a broaching machine, is excluded from this and indented
subclasses. Such devices are classified in Class 409, Gear Cutting,
Milling, or Planing, subclasses 288+ (for which see (1)
Note thereunder) and Class 83, Cutting, subclasses 875+. |
| | (8)
Note. A patent to apparatus for combined machining operations,
including broaching, is generally found in Class 29, Metal Working,
subclasses 33+, except in some instances where the combination
is specifically provided for in the class schedule of the other
(i.e., nonbroaching) machining operation. |
SEE OR SEARCH CLASS:
| 29, | Metal Working,
subclasses 90.01+ for a broacher combined with a burnisher where
the former is intended only to allow the latter to perform its function;
and subclasses 33+ for a combined machine which broaches
and performs another metal working operation. |
| 83, | Cutting, the generic residual class of cutting. |
| 407, | Cutters, for Shaping,
subclass 12 and 13+ for a broaching tool, per se. |
|