Improvements in Cutter Heads,
Year: 1899

page_text: Date of Application, 18th July, 1899-Accepted, 4th Nov., 1899
Improvements in Cutter Heads,
I, SAMUEL JOHNSTON SHIMER, of Milton, in the County of Northumberland
and State of Pennsylvania, United States of America, Manufacturer, 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:
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My invention relates to rotary cutter heads for wood working machinery of
that class or description known as expanding cutter heads, which consist of two
sections provided with flanges carrying the bits, one of which sections is movable
so that it may be caused to move away from or towards the other section to
vary the width of the groove cut. The object of the invention is to provide such
cutter heads with a scale by which the degree of expansion of the movable section
can be readily determined so as to cut a wider or narrower groove, as the case
may be.
The invention consists in the novel construction and combination of parts
hereinafter fully described and claimed.
In the accompanying drawings,
Fig. 1 is an elevation of a cutter head provided with my improved scale.
Figs. 2, 3 and 4 are similar views of the hub of the movable section, the
adjusting ring and retaining nut, showing them looking from different points.
Fig. 5 is a central longitudinal section of the same.
Fig. 6 is a plan view of the holding nut.
In the said drawings, the reference numeral 1 designates the lower section of
an expanding cutter head provided with flanges 2, formed with bit seats 3, to
receive the bits 4. This section is provided with a hub 5, having a screw bolt 6,
at the upper end provided with a jam nut 7, and means for holding the retaining
nut hereafter described, and preventing it from turning. These parts, however,
form no part of the present invention and a detailed description is therefore not
necessary.
The numeral 8 designates the upper section of the head which is movable with
respect to the lower section and is provided with flanges 9 formed with bit seats 10.
in the lower sides to receive the bits 12. The said sections are provided with
sleeves 13 and coiled springs 14 for expanding the same.
The hub of the inner or lower section is formed with peripheral screw
threads 15, there being sixteen to the inch. Fitting on this hub is an adjusting
ring 16 having corresponding threads by which the adjustment of the two sections
with respect to each other is effected. The adjacent ends of the hub of the upper
section and the said ring are serrated, as usual, in this class of heads. Above
said ring and working on the hub of the said lower section is a retaining nut 17.
The parts so far as described may be of any ordinary or suitable construction.
The hub of the upper section is formed below the nut with a number of
peripheral, concentric circles each of which is divided into four equal parts and
designated by suitable characters, the upper circle being designated by a cipher O,
and by the numerals 1, 2 and 3, consecutively arranged. The next circle is

page_text: designated by the numerals 4, 5, 6 and 7, consecutively arranged, and the next
circle by the numerals 8, 9, 10 and 11, also similarly arranged, these three
circles forming, of course, only a single continuous scale. Above the said ring
the retaining nut is formed with similar concentric circles also provided with
consecutively arranged numerals but which run in a reverse direction. The
adjusting ring at the limit of its movement is formed with characters numbered
17 which will be in coincidence with the ciphers on the hub and retaining nut
when said ring is at the lower and upward limit of its movement. The upper
end of said retaining nut on its upper side is provided with four marks or
characters 18, at equal distances apart. The said hub and retaining nut below
and above the adjusting ring are provided with arrows pointing in opposite
directions.
Before proceeding to describe the manner of using the invention, I would say
that in the present instance the head shown is designed to be used in connection
with either grooving or tonguing bits; the grooving bits when the head sections
are contracted to their limit partly overlap, but do not pass each other, and in
expanding said sections the bits of one section move away from those of the
other section, whereby the groove is enlarged, but the expansion is such that
the cutting edges are never far enough apart to be out of horizontal alignment,
but follow each other to cut the groove. The bits of the upper section cut the
upper side of the groove and the bits of the lower section cut the lower side.
When tonguing bits are used, they overlap and pass by each other and the
bits of the upper section cut the lower side of the tongue, while the bits of the
lower section cut the upper side, being the reverse of that above described with
respect to the grooving bits, so that when the sections are expanded the bits will
be brought nearer to each other, thus cutting a narrower tongue. This arrange-
ment of the bits, however, is not essential to the operation of the invention, as
the grooving bits may be arranged to overlap each other so that in expanding
they will cut a narrower groove, while the tonguing bits can be arranged to
cut a wider tongue when the sections are expanded. Again, two heads may be
employed, one to cut the groove and the other the tongue.
The manner of using the device is as follows:
The hub of the stationary section having threads on its periphery, sixteen to
the inch and the adjusting ring being correspondingly threaded, it follows that
at every quarter revolution of the said ring, the groove cut by the bits will be
one sixty-fourth of an inch wider or narrower according to the direction in which
the ring is turned, and that a complete rotation of the ring will cause the groove
cut to vary one sixteenth of an inch, and a rotation and a half will cause the
groove cut to vary 3/3 of an inch and so on. Supposing now that the adjustable
section is at its lowest limit and the retaining nut also at the lowest limit, then
the characters on the ring will register with the cipher marks on the hub and nut
as seen in Fig. 1, and supposing also that the bits are seven thirty-seconds of
an inch in thickness so that the groove cut will be one-fourth of an inch wide.
If the adjusting ring be now turned one quarter of a revolution to the right,
the sections will be expanded one sixty-fourth of an inch making the groove
cut one-fourth of an inch wide plus one sixty-fourth of an inch. The sections
will be expanded one sixty-fourth of an inch each quarter revolution of the
adjusting ring so that a complete revolution will give an expansion of four
sixty-fourths of an inch and four revolutions will give an expansion of one
quarter of an inch. The arrow on the retaining nut indicates the direction the
adjusting ring is to be turned in expanding the cutters to cut a groove while the
arrow on the hub is to indicate the direction of the movement for cutting a
tongue, because the groove bits or cutters work inside a groove while the tongue
bits or cutters work outside the tongue, and hence the section moves in the
opposite direction in expanding to cut an enlarged groove to that in which it
moves in cutting a tongue.

page_text: Should the expansion of the movable section be considerable, it may have
given the groove cut an undesirable location within the edge of the board. For
re-adjustment of cutter head on the spindle to locate the groove at the right
place mechanically without the use of a try stand, I make the thread of the top
screw to agree with the thread proportions in the adjusting ring and mark the
head of the retaining nut with four equi-distant characters and provide the top
screw on the upper side of its head with a double arrow to enable the operator
to proportion his adjustments of the cutter head up or down on the spindle by
moving the top screw to the right or left, to agree with the adjustment made
upon head sections.
For example, the tongue and groove on opposite sides of the flooring strips
must be cut at same relative distance from the bed of the machine which carries
the board as it passes through between the cutter heads. Say ¼ of an inch is
allotted to the under part of the tongue and groove, 1½ of an inch to the tongue
and groove proper, and 16 to the edge of the board above the tongue and groove.
These two relative positions for the cutter head are had by resting the top screw
upon the top of the spindle within the cutter head. Should it be necessary
however, to change the thickness of tongue and groove to 5/16 for any portion
of the flooring which is being made, loosen the set screw so that the several
sections of the cutter heads have a free movement and turn the adjusting ring
on the tonguing head one full turn around. On the groove head, you turn the
adjusting ring one full turn around in the opposite direction. As specified on
the several heads, the tongue and groove cutters will now be set to cut 5/16 tongue
and 16 groove, but by changing for the tongue we have raised the under tongue-
forming bit 16 of an inch up which will cut a face 5/16 of an inch below the
tongue instead of ¼ of an inch to which the levels were first set. This makes
it necessary to loosen the jam nut about the top screw and turn the said top
screw one turn around and fasten the jam nut. The cutter heads will now
be again adjusted to one level and will cut 5/16 tongue and groove.
From the above it will be seen that the workman or operator can readily
determine at a glance the degree of adjustment to be given to the adjusting ring
to vary the distance between sections, and can also readily tell the exact width
of the groove cut by simply noting the numeral with which the characters on the
adjusting ring coincide and adding to the width of the cutter the degree of
expansion indicated by said numerals and characters.
It is not necessary that the hub threads described should run sixteen to the
inch, and the numerals and characters on the hub, retaining nut and adjusting
ring should be arranged exactly as illustrated, but I have found the arrangement
shown as the most convenient in use.
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:-
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1. As an improved article, an expanding cutter head comprising the two
sections one of which is provided with a hub having a predetermined number of
screw threads to the inch, the movable section provided with a hub having its
periphery divided by a series of consecutively arranged numerals into a number
of equi-distant parts, the correspondingly threaded expanding ring provided
with a peripheral mark adapted to register with said numerals when said ring
is rotated and the retaining nut having an arrow or other character for indicating
the direction in which the adjusting ring is to be turned for widening and narrow-
ing the groove, substantially as described.
2. As an improved article, an expanding cutter head comprising the two
sections one of which is provided with a hub having a predetermined number of
screw threads to the inch and having on its periphery an arrow or other character,
the correspondingly threaded adjusting ring provided with a peripheral mark,
and the retaining nut having its periphery divided by a series of consecutively

page_text: arranged numerals into a number of equi-distant parts adapted to register with
mark on the adjusting ring, substantially as described.
3. In an expanding cutter head, the combination with the section provided
with a hub having a series of peripheral screw threads of a predetermined number
to the inch, of the movable section provided with a hub having its periphery
divided by a series of consecutively arranged numerals into a number of equal
parts, the correspondingly threaded adjusting ring provided with peripheral
marks, and the retaining nut provided with a series of consecutively arranged
numerals similar to but running in the reverse direction to those of the hub of
said movable section, substantially as and for the purpose specified.
4. In an expanding cutter head, the combination with the retaining nut having
its upper end divided by a series of marks into a number of equi-distant parts,
of the top screw, the head of which is marked on the upper side by a double
arrow, substantially as and for the purpose specified.
Dated this 18th day of July 1899.
BOULT & WADE,
Agents for the Applicant.