IMPROVEMENTS IN SCREW-CUTTING MACHINERY
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN SCREW-CUTTING MACHINERY." A communication from
abroad by Edward Nugent and David Tilton, both of Brooklyn, New York,
United States of America.
Sealed the 14th February 1879, and dated the 16th December 1878.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 16th December 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. IMPROVEMENTS IN SCREW-CUTTING MACHINERY."
A communication from abroad by Edward Nugent and David Tilton, both of
Brooklyn, New York, United States of America.
The objects of this Invention are as follows, namely:-To produce a screw-
cutting or threading machine so constructed that its parts will yield to any
irregularities for the purpose of avoiding breakage of the same; to construct a tool,
post, or cutter holder that may be more readily adjusted than others in use; to
provide a reversible die to take differently sized and shaped blanks and a moving
pan for carrying away the finished screws, so that they will not be mixed with the
chips from the cutter; also, to construct a more compact hopper than those now in
use with an improved automatic delivery into the feed race.

page_text: Figure Brews the reversible are, and Figure 6 the yielding clutch herein-after
described.
A is the main shaft; A' is the cutter shaft; E is the cutter holder; A is the
cutter; F is a gauge by which to set the cutter; is the screwdriver; N is the
former; O is an arm, the upper end of which is fast to the cutter shaft, its lower
end resting against the former N, and connected with the cam M by an arm N¹¹.
A spring P', connected with the frame and a lever running down from the former
holds the former against the lever O, thus holding the arm N against the cam M,
and these, by their joint action, communicate a rocking motion to the cutter shaft,
the spring P¹ acting to force the shaft inward to bring the cutter in contact with
the work, and the cam M to force it back.
The hopper which receives the blanks has a stationary part A", to which the
race N is attached, and a part B, which revolves with the shaft S¹. The two
parts are concave, their concaved sides facing each other, and at a distance from
each other sufficient to allow the body or shank of a screw blank to drop between
them; by these means the blank is suspended by its head, the shank hanging
between the parts B" and A".
A spring pin T, on the edge of the revolving part B engages the head of the
blank and carries it forward to the race N111, from which, suspended by its head, it
gravitates to the feeder, and drops into the socket R¹.
A bar C has a longitudinal motion, which it takes from a cam D.
A rock shaft C¹, attached to the feeder B, reaches up across the bar C, and is con-
nected to the frame by a spring V¹. On the bar C is a projection C"; this
projection engages a hook O' on the rock shaft C¹, and forces it back against the
tension of the spring V₁; thus as the bar C moves longitudinally it gives a rocking
motion to the rock shaft C¹ which carries the feeder B, the spring forcing it forward
and the bar C forcing it back.
A button J¹ is arranged to be turned against the rock shaft C', and thus stop the
feeder, while by the yielding of the spring V' the other parts may continue to move
without interruption.
I is a screwdriver which has both a longitudinal and a rotary motion. It takes
its longitudinal motion from the bar C by means of the arm T¹ which is firm and
unyielding. A part J is hinged to the part T¹ at one end, and held by a spring Ju
at the other end.
The screwdriver shaft is provided with a flange R", which enters and is held
between the two parts T and J, so that should the blank catch in the operation of
screw-cutting or threading, the screwdriver would be forced back and caused to
relax its hold on the blank. The screwdriver takes its rotary motion from a gear
wheel L on its own shaft meshing into a gear wheel K on the main shaft.
The cam D that moves the bar C takes its motion from a gear wheel T on its
own shaft meshing into a gear wheel U on the shaft with the cam Q, as also does
the cam M, which moves the former N. The cam Q forces the cutter shaft forward
longitudinally, a spring Kforcing it back, which is for the purpose of causing the
cutter to traverse the blank the proper distance and number of times to cut the
thread thereon.
The tool or cutter holder is provided with a collar C, which clasps the shaft,
and is held to it by a set screw, and kept from turning by a spline or feather.
'
A screw F¹ is provided with a large head which engages one end of the collar Cu
and a flange which engages the other end of the collar C. Said screw enters the
tool or cutter holder at the same radius as the outside radius of the collar C, so
as to continue its hold of the collar while the cutter holder may be turned on the
shaft. By turning the screw F1 the said cutter holder is moved lengthwise
along the shaft, and by turning the set screws K it is moved crosswise or trans-
versely to the said shaft, the one adjustment not interfering with or changing the
other adjustment. The cutter is provided with a stop gauge F", by which it is set

page_text: much more easily and readily than without it; as when it is taken out to sharpen
it is by this gauge readily put back in the same position as before.
Reversible dies are provided, which are made round, and provided with different
grooves to receive differently sized and shaped blanks; said die is shown by
Figure 5.
The gear wheel S is connected to the main shaft by means of a bevelled clutch X,
held by a spring Z of sufficient strength to carry the working parts, but so that it
will allow the clutch to slip out should any part of the machine get caught, thus
avoiding breakage.
The operation of this machine is as follows, that is to say:-The blanks are
taken from the race N¹¹ by the feeder B, and carried downward to the back die F,
which is forced forward by an incline on the bar C, and grips the blank with its
head toward the screwdriver I against the die E¹, the latter having a spring Y
enabling it to yield if a screw fails to drop into its proper position. At this time
the screwdriver moves lengthwise, its point enters the nick in the head of the blank
and revolves it against the cutter A, the former forces the cutter inward, and
brings its point in contact with the blank; the cutter shaft is forced lengthwise by
this cam Q, and is each time forced back by the spring K¹, which operation is
repeated a sufficient number of times to finish the thread when the parts recede,
and the finished screw drops into the receptacle below. As the screw drops it
is caught by a moving pan 0", which is made to present itself just at the proper
time by means of a connection with a trip on the main shaft (not shewn in the
Drawing). This last contrivance is for the purpose of preventing the mixing of
the chips with the screws.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it under-
stood that I claim,―
First. The combination of the cam, the spring, the lever, and the former N,
arranged to produce the rocking motion of the cutter shaft as and for the purpose
set forth.
Second. The tool or cutter holder arranged on the cutter shaft in combination
with the collar and screw for effecting the adjustment, either lengthwise or trans-
versely to the shaft, in such a manner that the one adjustment does not affect or
interfere with the other, as above set forth.
Third. The stop gauge by which to set the cutter in combination with the cutter
and tool holder, as and for the purpose set forth.
Fourth. The combination of the die E' with the die holder and spring, as and for
the purpose set forth.
Fifth. The hinged part J attached to the arm T¹ by the spring in combination
with the screwdriver shaft, and connected thereto by the flange, as and for the
purpose set forth.
Sixth. The spring connecting the rock shaft of the feeder to give to it the forward
motion necessary to convey the blank downward to the cutter in combination
with the projection on the bar C for forcing it back, as and for the purpose set
forth.
Seventh. The hopper having a stationary part and a revolving part in combina-
tion with the race N111, as and for the purpose set forth.
Eighth. The connecting of the main gear wheel by means of the yielding clutch
to its shaft, as and for the purpose set forth.
Ninth. The reversible die shown in Figure 5 of the Drawing, and adaptable
to different kinds of screws, as and for the purpose set forth.
Tenth. The moving pan for catching and carrying off the screws to preserve
them from the falling chips, as and for the purpose set forth.
Eleventh. A screw-cutting or screw-threading machine, consisting of the parts

page_text: shewn in the accompanying Drawings, and constructed and operating as above
set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Sixteenth day of December, in the year of our Lord
One thousand eight hundred and seventy-eight.
W. ROB, LAKE. (L.S.)