An Improved Mode of Manufacturing Rotary Paring Cutters.
Year: 1892

page_text: Date of Application, 8th Mar., 1892
Complete Specification Left, 8th Dec., 1892-Accepted, 28th Jan., 1893 .
PROVISIONAL SPECIFICATION.
An Improved Mode of Manufacturing Rotary Paring Cutters.
1, ARTHUR KEATS, Machine Maker, of Marston Road, Stafford, in the County
of Stafford, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to manufacture rotary paring cutters (such
more economical manner than
as those used in sole-paring machines) in a
heretofore.
To this end I prepare discs of steel as cutter blanks, of a thickness corresponding
to the breadth of cutter desired to be produced, and turn them down in a lathe
to the profile corresponding to the work to be done. The blanks thus prepared I
mount severally on a horizontal spindle carried by a slide, and fitted to a dividing
wheel. Supposing the cutter is to be made with 12 cutting edges, the divisions of
the dividing wheel will correspond, thereto, and the blank will be locked in position
on the slide, to meet the action of the milling tool.
The first operation on this shaped blank, to mill off a portion of the periphery,
by traversing the blank under a stationary milling tool until it is reduced to a
polygonal form. The milling tool is formed with a profile corresponding to the
profile of the blank, and in traversing the blank under the milling tool, the profile
As cach cut is made,
will be preserved in the flattened portions of the blank.
the blank is drawn back, and is moved round on its axis, to bring it in position to
receive a second cut from the milling tool. In this way, the blank is reduced to a
12-sided figure, by passing it a corresponding number of times under the action of
the profile milling tool. The next operation is to convert these flattened portions
of the blank into cutters.
To this end, the blank is removed to another milling machine, and presented by
the aid of a dividing wheel to a descending milling tool, which will pass through
the perimeter of the disc, making a tangential cut through the same, and forming
thereby a cutter which overlies the space that provides for the escape of parings
from the cutter's edge when the tool is in use. This milling tool is brought down
and caused to enter the blank at the angle where the adjacent flattened portions
meet, and the blank being presented 12 times to this descending milling tool, by
means of a dividing wheel the required number of cutting edges will be formed in
the paring tool.
The sharpening of this tool will readily be effected by passing through the
tangential cuts an emery disc, which, in its action, will maintain the original form of
the cutter. From the above description it will be readily understood that the
rake of the cutters produced by the action of the first milling tool, will be maintained
throughout the existence of the paring tool, and that without requiring any special
operation for the purpose.
Dated this 8th day of March 1892.
NEWTON & SON,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
An Improved Mode of Manufacturing Rotary Paring Cutters.
I, ARTHUR KEATS, Machine Maker, of Marston Road, Stafford, in the County
of Stafford, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and, ascertained in and
by the following statement :-
The object of this invention is to manufacture rotary edge-paring cutters (suit-
able for use in sole paring machines) in a more economical manner than heretofore.
To this end, I prepare, by forging, hollow cylindrical discs of steel, as cutter
blanks, of a thickness corresponding to the breadth of cutter desired to be
produced, and I turn them down in a lathe to the profile corresponding to the work
to be done.
In the accompanying drawing,
Fig. 1 shews in side view, and Fig. 2 in cross section, a blank turned down to the
form of profile desired for the edge-paring cutter.
A flange 1 is thus formed on one edge of the disc, and two annular indents serve
to form the part 2, which is rounded in cross section, while the part marked 3 at
the other edge of the blank, is untouched by the profile-turning tool.
This configuration of the profile. of the cutter is intended to produce a cutting
edge of the width of the disc, the flanged portion serving to make a chamfer cut, the
rounded part to hollow out the work, and the flat part beyond it, to limit, for the
reason to be presently mentioned, the depth of the cut.
The blanks thus prepared I mount severally on a horizontal spindle (see Figs. 3
and 4), which spindle is carried by a slide that has fitted on it a dividing wheel.
Supposing it is desired to make the cutter with 12 cutting edges, the divisions of
the dividing wheel will correspond thereto, and the blank will be locked in position
on the slide,, to meet the action of a profile milling tool.
Fig. 3 shews in side view, and Fig. 4 in edge view, the blank A under the action
of. a rotatory profile cutter B, for the conversion of the same into a twelve sided
figure.
Two cuts, it will be seen, have been already made, and the work is now advancing
under the profile cutter, to undergo a third operation of the milling tool. By
reference to Fig. 4, it will be seen that the whole breadth of the cutter blank is
not touched by the milling tool, but the part marked 3 remains unchanged, or as it
left the lathe. The rest of the breadth of the disc included in the cut of the
milling tool. (which cut, covers one twelfth of the perimeter of the disc) is flattened,
while still retaining its profile figure. Thus, the parts
and 2 lose the convex line
of Fig. 1, and take the straight, line indicated. at Figure 3.
The traverse of the blank under the stationary milling tool, is continued until it
is reduced to the desired polygonal form (see Fig. 5). The milling tool is formed
with a profile corresponding to the profile of the blank, and in traversing the blank
under the milling, tool, the profile will be preserved in the flattened portions of the
blank. As each cut is made, the blank is drawn back, and it is moved round on its
axis by hand or otherwise, to bring it into position to receive a second cut from the
milling tool, and so on, until the profile shaping is completed. The next operation
is to convert these flattened, portions of the blank into cutters.
To this end, the blank is removed to another milling machine, and presented, by
the aid of a dividing wheel, to a descending milling tool, which will pass through
the perimeter of the disc, making an inclined cut through the same.
Fig. 5 shews in side view the cutter blank as being operated upon by a milling
tool C, to produce the cutting edges, which overlie the spaces that provide for the
escape of parings from the cutting edges, when the tool is in use. This milling tool,
it will be seen, is wedge shaped in section, to provide for a comparatively wide cut

page_text: at the periphery of the blank, while a comparatively small amount of metal is
removed from the root of the cutting teeth formed by the tool.
The milling tool is proportioned to the perimeter of the blank, it being designed
to remove, say, one half of the perimeter by its transverse cut.
The proper inclination given to the cut of the milling tool, to ensure a good
clearance, is best attained by following the rule indicated at Fig. 5, where 4 is a
dotted circle concentric with the blank, and of which the dotted line 5 is a tangent.
This line 5 indicates the direction in which the cut of the descending milling tool
is to be made.
The diameter of this circle, which is 14 inches, gives a suitable proportion
for a cutter of the size indicated at Fig. 5, and measuring 28th inches in diameter.
The milling tool is caused to enter the blank at the angle where the adjacent
flattened portions meet, and thus, in the act of producing the edge of one cutter, it
forms the heel of the adjacent. cutter, the radius of which is less than that of the
cutting edge. An efficient rake is therefore provided for the cutting edge, which
acts after the manner of a chisel in paring the leather presented to it. The blank
being presented 12 times to the descending milling tool by means of a dividing
wheel, the required number of cutting edges will be formed, and the paring tool
will then present the appearance shewn in side view at Fig. and in edge view
at Fig. 7.
The sharpening of this tool will readily be effected by passing through the
transverse cuts an emery disc, which, in its action, will maintain the original form of
the cutter. From the above description it will be readily understood, that the rake
of the cutters produced by the action of the first milling tool, will be maintained
throughout the existence of the paring tool, and that without requiring any special
operation for the purpose.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
The mode of manufacturing paring cutters as described with reference to the
accompanying drawing, and for the purpose set forth..
Dated this 8th day of December 1892.
►במזזו
NEWTON & SON,
Agents for the Applicant.