Improvements in Cutter-heads for Wood-working Machines, and in Cutting-bits for the same.
Year: 1891

page_text: Date of Application, 28th Apr., 1891-Accepted, 27th June, 1891
COMPLETE SPECIFICATION.
Improvements in Cutter-heads for Wood-working Machines, and in
Cutting-bits for the same.
I, SAMUEL JOHNSTON SHIMER, a citizen of the United States of America,
residing at the town of Milton, in the County of Northumberland, in the State
of Pennsylvania, Gentleman, do hereby declare the nature of my invention for
CUTTER-HEADS FOR WOOD-WORKING MACHINES, AND FOR CUTTING-BITS
FOR THE SAME, and in what manner the same is to be performed, to be
particularly described, and ascertained in and by the following statement:-
My invention has relation to cutter-heads for wood-working machines, of that
class wherein the cutter-head is secured to a vertically rotatable spindle or arbor,
and provided with bit-seats formed on opposite surfaces of the body flange of
the cutter-head, and having bits in the bit-seats, arranged to give a clearance
cut in tongue and groove cutting usually styled matcher-heads, and the object
is to provide improved constructions for securing the bits in their seats in the
cutter-head; my invention therefore, consists in the novel construction of parts or
elements, and their combination, as will be fully specified, and particularly pointed
out in the claims.
I have fully illustrated my invention in the accompanying drawings, wherein :-
Figure 1 is a perspective of my improved cutter-head, equipped with bits.
Fi
Figure 2 is a bottom view of the same.
Figure 3 is a perspective of the head without the bits.
Figure 4 is a vertical central sectional view, showing the bits in the seats and
one of them removed.
Figure 5 is a top view of a bit.
Figure 6 is a bottom view of a bit.
Figure 7 is a bottom view of another form of bit.
Figure 8 is a section on the lines 1-1 of Figure 6.
Figure 9 is a view on the line 2-2 of Figure 6.
Figure 10 is a view of the clamping-bolt.
A designates the cutter-head formed with a hub 3, having a bore 4, for the
spindle and formed with an extending body-part 5, constituting the part or flange
in which are located the bit-seats. These bit-seats are arranged in pairs, two 6, 7,
being oppositely arranged in the under surface at right angles to those shown;
so that the bits are carried by the head at substantially right angles to cach
other, at radii of the flange. The bottom or floors of the respective bit-seats have
a general inclination to the plane of revolution of the cutter-head, the two upper
seats being inclined upwards and the two lower ones inclined downwards from the
direction of rotation, so that the bits secured therein may have their proper
relative positions and be given the requisite clearance in the cup. Substantially in
the centre of each bit-seat, where the circle of the seat is completed, is formed a
bolt-hole 10, to receive the bolts which hold the respective bits in their seats, and
in each bolt-hole is a lug 11, which engages a groove in the bolts and keeps them
from turning when being screwed up or when removing the holding-nuts.
My present invention as applied to the cutter-head consists in constructing the
bit-seats in the cutter-head with dished out middle portion 12, forming a cup-
shaped or conical depression, constituting a seat to receive and hold the similarly
shaped bottom of the bits. The wall of the conical seats terminates, preferably,
in an annular flange or shoulder 13, surrounding the hole through which the
clamping-bolt passes.

page_text: B designates the bits, which are formed with a cutting rim or flange as shown
and are of the circular form employed in matcher cutter-heads for tongueing and
grooving boards. My invention as forming a part of the bits consists in making
them with a conical bottom or middle portion 14, surrounding the bolt-holes in the
bit and adapted to set flush in the depressions or bit-seats in the head so that the
clamping-bolts will draw them tight on the head. The bottom of the conical or
cup-shaped projection preferably terminates in an annular rim-flange 15, which
leaves the wall of the conical part stronger at this part and less liable to chip
or crack.
About the top of the conical bottom may be a shoulder, or the extended flange
of the bit may be extended immediately therefrom, as shown in Figures 6 and 7 of
the drawings. The interior of the bits are dished out as seen at 16, making the
middle portion surrounding the bolt-hole concavo-convex, the concave surface
forming a conical seat for the under face of the clamping-bolts 17. The clamping-
bolts have a groove 18, cut in them in which the lug 11 sets when the bolt is in
place, and as stated, the bolts are thereby kept from turning when being tightened
or loosened.
The conical constructions of the bottoms and the bit-seats give a stronger grip
The
on the bits in the seats in the head than in the flat bottomed constructions.
bits also, have a greater seating surface and are located out of the direct line of the
force of the cut.
It will be perceived by examination of the drawings that the bits rest in the
The con-
conical seats and do not rest on the extensions surrounding them.
struction also, serves as a guide in keeping the bits accurately in position when
loosened and when adjusting them.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In combination the cutter-head formed with bit-seats having the middle
portions around the bolt-holes dished out in conical shaped seats, circular cutting-
bits formed with conical shaped bottoms projecting from the body of the bit to set
in the bit-seats of the cutter-head, and clamping-bolts projected through the bits
and head, substantially as described.
2. In combination the cutter-head formed with inclined bit-seats alternately
arranged on opposite sides of the head-flange and formed with conical depressions
in their middle portions, circular bits in the bit-seats formed with conical pro-
jections on their bottoms to set in the conical depressions of the seats in the
head, and clamping-bolts projected through the bits and head substantially as
specified.
3. In combination the cutter-head having inclined bit-seats alternately arranged
on opposite sides of the head-flange and formed with conical depressions in the
middle portions, circular cutting-bits in the bit-seats formed with concavo-convex
portions surrounding the bolt-holes to set in the conical depressions of the bit-seats
and take the under side of the head of the clamping-bolts, and clamping-bolts
having heads to set in the concavity of the bit, substantially as described.
4. The circular bit for a cutter-head herein described, consisting of a body
formed with a cutting rim or flange a clamping-bolt-hole, and a conical shaped
bottom portion projecting from the body of the bit, and surrounding the bolt-hole,
substantially as and for the purpose specified.
5. The circular bit for a cutter-head herein described, consisting of a body
formed with a cutting-rim or flange, a clamping-bolt-hole and a concavo-convex
middle portion projecting from the body of the bit and surrounding the bolt-hole,
substantially as and for the purpose specified.
6. The cutter-head herein described formed with bit-seats alternately arranged
on opposite sides of the head-flange, bolt-holes in the seats, and conical depressions

page_text: surrounding the bolt-holes, which latter are in parallel plane with the spindle bore
of the cutter-head, substantially as and for the purpose specified.
Dated this 28th day of April 1891.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.