Improvements in Screwing or Thread Cutting Machines.
Year: 1897

page_text: Date of Application, 27th May, 1897-Accepted, 31st July, 1897
COMPLETE SPECIFICATION.
Improvements in Screwing or Thread Cutting Machines.
I HENRY ALEXANDER FERGUSSON of 514 Summit Avenue, Jersey City, New Jersey,
U.S.A., Mechanic, do hereby declare the nature of this invention and in what mauner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :—
In the accompanying drawing Fig. 1 is a plan view of a portion of the screwing or
thread cutting machine of this invention. Fig. 2 is a vertical longitudinal section on
line 2-2 of Fig 1. Fig. 3 a tranverse section on line 3-3 of Figs. 1 and 2. Fig. 4 a
longitudinal central section on an enlarged scale through the screw or bolt carrier and
its operating mechanism. Fig. 5 a bottom view of said carrier and parts connected
therewith. Fig. 6 a detail view on an enlarged scale of the locking mechanism.
Fig. 7 a plan view of a modified form of screw or bolt carrier and Fig. 8 a vertical
longitudinal section of the same. Fig. 9 shews the screw or holt holding ring
developed. Fig. 10 a detail view in front elevation of a vise or bolt holder which may
be employed in place of the carrier, and Fig. 11 is a plan view and Fig. 12 a
longitudinal central section of the same.
A is one end of a holt screwing machine which may be suitably constructed and
supported. The cutting or threading dies may be of the usual construction and are not
shewn. At one end of the bed plate is secured a bolt carrier I with supporting frame
and guide B. This frame has flanges which are securely bolted to the bed, and
upwardly projecting sides having enlarged heads 2 that have a dovetail
connection with lugs e projecting downwardly from the carriage C the arrangement
being such that the carriage or plate C is not only supported in a horizontal
position, but is guided as it is reciprocated longitudinally towards and from the
cutting dies. The dovetail connection is such as to prevent a vertical movement.
The frame B is formed with, or supports a cylinder D having a reciprocating
piston D1 the rod of which is connected with an arm E secured at e to the
carriage C. The cylinder should be equipped suitably to be operated by fluid
pressure.
Preferably, compressed air is employed which is admitted through a pipe F to a
valve casing from which project branch pipes F, F, leading to the front and rear
ends of the cylinder. An arm f' extends from the valve f2 and by suitably operating
this arm air may be admitted to either end of the cylinder. Any suitable exhaust
may be employed. When the mechanism is properly operated, the carriage C and the
carrier I which is connected therewith will be reciprocated automatically towards and
from the cutting dies.
In order to automatically reverse the movement of the apparatus at proper times,
stops G, G¹, are employed secured to a rod G2 fastened to brackets
that are
secured to the carriage C. Preferably the rod G² is square, so as to prevent the
stops G, G¹ from turning. These stops are provided with set screws g¹ by which they
may be set properly and in any desired positions on the rod, and they are provided
with laterally projecting lugs g² that are adapted to engage with the arm f" the
arrangement being such that at the end of each stroke of the carriage the arm fis
shifted to operate the valve to admit compressed air to one or the other end of the
cylinder to cause a uniform and constant reciprocation of the carrier. A bracket H
'

page_text: is secured to the carriage C and it supports a rod H¹ having stops h, h¹, that operate
the mechanism for opening and closing the cutting dies. These stops are adjustable
and may be set correspondingly with the stops G, G¹, to open and close the dies at
the proper time to conform to the stroke of the carrier I and the length of bolts
carried thereby.
The bolt carrier I is preferably cylindrical and is formed with a boss i that extends
through the carriage C. Beneath the carriage C is a disc J through which extends
the squared shank K of a bolt k. The squared shank also extends through the boss i
and the bolt passes through the carrier I and receives on its upper end a nut
and a washer 2. Thus the carrier I and the disc J are free to turn relatively 1
to the plate or carriage C. The carrier is provided with a series of recesses M in
which are fitted recessed blocks M. Preferably the blocks have a dovetail sliding
connection with the carrier and may be inserted and removed vertically. Each of
the blocks is recessed in such manner as to receive the head of a bolt, and it is slotted
at m to receive the shank of the bolt, (Fig. 4). The recess in the block preferably 1
extends from top to bottom thereof, while the slot. m which is narrower than the
recess, extends from the top downwardly about one half the depth of the block.
Within each recessed block is arranged a spring N. Its lower free end n is adapted
to bear against the head of the bolt, (Fig. 4). Its upper end is bent and secured
beneath a plate L. secured to the top of the carrier I which also serves to hold the 2
blocks in place. These springs not only serve to hold the bolts in a true horizontal
position, but also take strain or shock from the dies when the bolts come in contact
with them.
The carrier I is locked to the carriage C by means of a bolt O having a square
shank o extending through the carriage. The head of the bolt is adapted to fit, when 2
depressed, in a recess in the carriage, and it is normally pressed upward by a spring o¹.
The end of the bolt is adapted to enter a series of recesses o2 corresponding in
number with the number of bolt holding blocks M¹. The lower end of the shank of
the bolt () is secured to a latch lever P having a curved rear end p adapted to engage
with a tripping block Q secured to the frame B and adjustable thereon. This block 3
extends through a longitudinal slot q in the frame and is secured in place by a bolt
and nutq It is flanged at q2 and recessed at q³ to receive a pivotted dog R. The
The
block Qinay be adjusted to any desired position, within the limits of the slot
end p of the lever P is adapted to engage with the flange of the block Q. When thus,
engaged, (Fig. 6) the bolt will be withdrawn from engagement with the carrier, and
the latter will be free to turn relatively to the carriage C. As soon, however, as the
lever P is moved away from the block the bolt will be raised by its spring o¹ and thus
lock the carriage and carrier together. The disc J is provided with a series of
downwardly projecting pins S which are adapted to engage with the dog R which
projects from the block Q. This dog is pivotally connected with the block and is
held in position by a spring r. The pivotted dog is arranged in a recess in the block
and may be turned to the left, (Fig. 5) to enter the recess, but it is held against
farther movement to the right by the walls of the block. In Fig. 5 the parts are in
such position that the carriage C and the carrier I are locked together. When the
carriage and carrier are moved farther to the right, the latch lever P will first ride
over the top of the block Q thus disengaging the locking bolt O, and then one of the
pins S will strike against the dog R. As the carriage and carrier farther move to
the right the latter will be turned about its axis one sixth of a revolution. By this
arrangement the bolt holders in the carrier may be successively brought into
proper position to present bolts successively to the cutting dies. In operation
the pin which engages the dog R will, after it is turned, pass by the dog, but
on the return of the pin the dog will yield to allow the pin to pass it without
moving it, and the bolt O will properly operate to lock the carriage and carrier
together. The mechanism is so timed as to operate harmoniously. The carrier is
locked and unlocked and turned at or near the end of its backward stroke, and
the valve controlling the fluid pressure is correspondingly operated at the proper
time to advance and retract the carrier when it is in proper condition to present

page_text: a bolt to be threaded or to withdraw a threaded bolt from the dies. Likewise
the stops h, h¹ are adjusted to open and close the dies at proper times relatively
to the adjustment of the carrier operating mechanism.
The carrier may be constructed as shewn in Figs. 7, 8, and 9, this special
construction being preferred. In this instance the carrier is provided with a series of
recesses in which are mounted a series of recessed blocks or liners T having inwardly
projecting studs t abutting against spiral springs t located in radial recesses t² in the
cylinder. An annular plate V is secured around the periphery of the carrier, and is
provided with a series of slots or recesses to receive the shank of the bolts. The
slots are of different widths to accommodate bolts of different diameters (Fig. 9).
There should be a series of slots or recesses of the same width, and also separate series
of other slots or recesses, so that a number of bolts of the same diameter may be
operated upon when desired, and then the plate may be shifted to operate on bolts of
different diameters. The plate is provided with a series of holes u¹ to receive a bolt
or screw u² for securing it in position. The arrangement of the holes is such as to
properly locate the plate relatively to the recesses in the carrier. Sometimes it is
desirable to operate on bolts of great length or of larger diameter than usual. It is
then preferred to remove the carrier and replace it by a vise V of usual construction, such
as shewn in Figs. 10, 11, 12. The carrier may be readily removed by withdrawing the
bolt and the disc J and securing the vice in position on the carriage C by locking
devices W as indicated in Figs. 10, 11, 12.
When operating with a revolving carrier, it is necessary before admitting the
compressed air to the cylinder to accurately set the machine for the bolts to be cut.
Blocks M of proper construction are first placed in position, and the springs N are
clamped tightly in place. The blocks are filled with the bolts to be cut, and the
stop is set to open the die holder when a thread of sufficient length is cut, and the
stop G¹ is set to turn the valve fat the moment the die holder is opened to admit air
to the front end of the cylinder. The block Q is moved until the dog R strikes one
of the pins $ in the disc J. Ther the bolt ( will be withdrawn, and the block should
be firmly clamped in position. The carriage C is then drawn back until the carrier is
turned sufficiently to bring another bolt into position. Then the stop h should be
clamped so as to close the die holder in readiness for the next bolt. The stop G is, in
its turn, set to turn the valve to admit air to the back of the cylinder. When the
adjustments are thus made, the compressed air may be turned on and the machine
started. Compressed air enters the back of the cylinder, thus forcing the carriage
forward and pressing the bolt held in the carrier against the dies, which begin to cut
the thread. As the thread is being cut the valve will be gradually turned until air
is admitted to the opposite end of the cylinder. Then the die holder will open and the
slide will move back. The locking bolt is withdrawn, and the carrier is turned until
a new bolt is brought into proper alignment. Then the die is closed and the valve
again adınits air to the back of the cylinder. These movements are repeated to cause
the continuous operation of the machine. As each bolt is threaded it is removed
from the carrier and replaced by an unthreaded one. The machine, is entirely
automatic, the operator being only required to remove the threaded bolt and replace it
by an unthreaded one at each operation.
When the vise (Figs. 10 11 12) is used in place of the carrier, the stop G¹ is set to
turn the valve to withdraw the bolt from the die after the thread is cut, and the
stop G is slipped back out of use. When the uncut bolt has been clamped in the vise,
the valve is turned to admit air to the back the cylinder by hand.
said
Having now particularly described and ascertained the nature of my
invention and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination of a revolving bolt carrier having a series of devices for
carrying the bolts, a reciprocating carriage, fluid pressure operating mechanism for
actuating the carriage, a rod mounted on the carriage and carrying devices for opening
and closing the dies, devices carried by the carriage for controlling the operation of the

page_text: fluid pressure mechanism to reciprocate the carriage, and mechanism actuated by the
reciprocation of the carriage to turn the carrier, substantially as described and
shewn.
2. The combination of the sliding carriage, the revolving bolt carrier mounted
thereon, the pins projecting from the carrier for revolving it, the dog engaging the
pins at each reciprocation of the carriage to turn the carrier, a cylinder, a piston,
connections between the piston and the carriage, a valve for controlling the admission
of fluid to the opposite ends of the cylinder, devices carried by the carriage for
operating the valve, and devices also carried by the carriage for opening and closing
the dies, substantially as described and shewn.
3. The combination of a reciprocating carriage, the revolving bolt carrier mounted
thereon, a series of downwardly projecting pins connected with the carrier, a locking
bolt, a latch lever for operating it, an adjustable tripping block for operating the latch
lever, and a dog carried by the adjustable block, adapted to act on the pius to turn the
carrier, substantially as described and shewn.
4. The combination of the reciprocating carriage, the revolving bolt carrier carried
thereby, a bolt for locking the carrier to the carriage, a latch lever for operating the
bolt, downwardly projecting pins connected with the carrier, an adjustable tripping
block acting on the latch lever, a dog carried thereby, acting on the pins, a cylinder,
its piston, connections between the piston and the carriage, a valve for controlling the
admission of fluid to the cylinder, and adjustable stops carried by the carriage for
controlling the movement of the valve, substantially as described and shewn.
5. A bolt carrier having a series of recesses in its periphery, and an adjustable
annular plate secured to its periphery and provided with a series of slots or recesses of
different widths, substantially as described and shewn.
6. The general construction, arrangement, and combination of parts constituting
the screwing machine and means for operating the same, substantially as described and
shewn.
Dated this wrth dow of M. 1907
THOMAS R. SHILLITO,
89 Chancery Lane, London, W.C., Agent for the Applicant.