IMPROVEMENTS IN MACHINES FOR FLUTING OR GROOVING CYLINDRICAL SURFACES
Year: 1883

page_text: LETTERS PATENT to William Robertson of Johnstone in the County of
Renfrew Engineer for an Invention of "IMPROVEMENTS IN MACHINES FOR
FLUTING OR GROOVING CYLINDRICAL SURFACES”
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PROVISIONAL SPECIFICATION, left by the said William Robertson at the
Office of the Commissioners of Patents on the 6th July 1883.
WILLIAM ROBERTSON, of Johnstone, in the County of Renfrew, Engineer,
"IMPROVEMENTS IN MACHINES FOR FLUTING OR GROOVING CYLINDRICAL
SURFACES,"
This Invention relates to improvements in the construction of machines adapted
for spirally fluting or grooving cylindrical bodies, such as the rollers used in roller
grinding mills, for cutting screws and for rifling or cutting internal spiral grooves
in ordnance. Such fluting or grooving is effected by imparting a slow motion of
rotation to the roller or other body being operated upon, while the cutting tool is
traversed longitudinally.
In one modification the machine consists of a bed or frame on which are formed
two or more slides (on opposite sides of the work) fitted with carriages and tool
boxes which are worked to and fro by screws geared together at the ends by spur
wheels gearing into a central driving wheel which is fixed on a shaft passing up
the centre of the bed. This shaft, at the opposite end to the gearing, carries a
mitre wheel which gives motion to a cross shaft passing out at the side of the bed,
and which in turn gives motion to a train of change wheels, mounted on a swing
plate and gearing into a quadrant slung loose on a spindle which is fitted into a
headstock cast or fitted on the bed. The front end of the spindle is fitted with a
grab chuck for taking hold of the work to be operated on. This spindle also
carries a worm wheel which is keyed on and gears into a worm on an upright
shaft carried by brackets formed on the loose quadrant...
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The top part of the quadrant is formed with a swing plate and a train of change
wheels which give motion to the wheel on, the spindle, by a ratchet wheel acting
on a fixed pawl carried by an arm on the top of the head of the machine. This

page_text: arm is capable of being set to any angle on either side of the centre line of the
head, so that either right or left hand spirals may be cut. While the cutting tool
is moving longitudinally, a rotating motion is given to the work being operated on
through the first set of change wheels and the loose quadrant, but as the loose
quadrant also carries the upright .shaft and worm gearing into the fixed worm
wheel it is locked and carries the spindle and work along with it, thus giving the
desired twist to the groove. The top end of the quadrant and second swing plate
with the ratchet wheel, are carried on the forward stroke past the arm with the
fixed pawl (this pawl being hinged) without moving the gear; but on the back or
noncutting stroke of the machine, the ratchet comes in contact with the pawl and
moves one or more teeth, which. motion is communicated through the change
wheels, upright shaft and worm wheel and spindle; and the spindle is advanced
according to the pitch of the groove in the roller. The pitch and number of
grooves in the roller or other surface can be varied to any required. extent by
means of the change wheels. The slides and carriages are worked to and fro by
any convenient gearing to give a slow forward motion to the cut, and a quick
return; as in ordinary, planing machines, either by the use of an open, and a cross
belt, or by a saw-tooth clutch or a friction clutch, the reversal being effected by a
tappet rod acted on by one of the slides. I prefer to throw the tool or tools out
of the cut at the end of the stroke and keep it clear of the work when running
back and throwing it in when the machine reverses, which can be done in various
.ways, for example by having a spring at each end of the machine for each tool
holder with chains attached, and so set that the one pulls the tool out, and the
other pulls it in; or by having two shifting brackets fixed to 'the slide with
projecting fingers to act on the tool holder at front and back, or by connecting a
crank or eccentric to the tool to take it out of action at the back stroke.
To convert the machine into a screw cutting machine it is only necessary to
take off the quadrant and substitute a wheel which requires to be keyed on the
spindle.
One screw and one slide, may carry, two, three, or, more tools for either fluting or
screw cutting, and a set of change wheels and swing plate may be used for varying
the speed of the cutting tools
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robertson in the Patent Office on the 4th January: 1884..
WILLIAM ROBERTSON, of Johnstone, in the county of Renfrew, Engineer, 3
IMPROVEMENTS IN MACHINES FOR FLUTING OR GROOVING CYLINDRICAL.
"
SURFACES
"
.
My said Invention relates to improvements in the construction of machines
adapted for spirally fluting or grooving cylindrical bodies, such as the rollers used
in roller grinding mills, for cutting screws; and for rifling or cutting internal spiral 4
grooves in ordnance,
[!

page_text: Such fluting or grooving is effected by imparting a slow motion of rotation to
the roller or other body being operated upon, while the cutting tool is traversed
longitudinally.
My Invention is illustrated by the accompanying Drawings, in which Figure 1
is a side elevation, Figure 2 is a plan, and Figure 3 is an end elevation showing
one modification of the improved roller-fluting machine. This machine consists of -
a bed or frame A, on which are formed two or more slides A' (on opposite sides of
the work) fitted with carriages B and tool boxes B', which are worked to-and-fro
by long screws C geared together at the ends by spur wheels D D gearing into a
central driving wheel D' which is fixed on a shaft E, passing up the centre of the
bed A. This shaft E, at the opposite end to the gearing, carries a mitre wheel E';
which gives motion through a wheel E³ to a cross shaft F passing out at the side
of the bed A, and which by means of a pinion F¹ on it, gives motion to a single or
double train of change wheels g g, mounted on a swing plate H pivotted on a
stud h, and through a worm i, actuating a quadrant or worm wheel I, slung loose
on a spindle I, which is fitted into a headstock A² cast or fitted on the bed A.
The front or inner end of the spindle I' is fitted with a grab chuck or catch I³ for
taking hold of-the work to be operated on; that is, for example, for gripping the
shaft or mandrel, on which the roller to be grooved is carried, bearing blocks i being
provided to support and steady the work. This spindle I also carries a worm
wheel J which is keyed on and gears into a worm J¹ on an upright shaft Jª carried
by brackets formed on the loose quadrant or wheel I. The top part of the
quadrant I is formed or fitted with a swing plate K and a single or double train of
change wheels k le k, which give motion to the wheel J on the spindle I' by a
ratchet wheel L acting on a fixed pawl carried by an arm or bracket L'on the
top of the head A2 of the machine. This arm is capable of being set to any angle.
ou either side of the centre line of the head A', so that either right or left hand
screws may be cut in the rollers. The cutting tools carried by the carriages B
are traversed longitudinally by means of the screw shafts C, as in a slide lathe,
while a rotating motion is given to the rollers or other work being operated on,
through the first set of change wheels g, g, and the loose quadrant or wheel I, and
spindle I¹; but as the loose quadrant or wheel I also carries the upright shaft Ja
and worm J¹ gearing into the fixed worm wheel J, this wheel is locked and carries
the spindle I' and the work along with it, the desired twist being given to the
groove cut in the roller by the combined traverse of the cutting tool and motion of
rotation of the work. The top end or a bracket I* fixed on the quadrant or wheel I
and second swing-plate K with the ratchet wheel L are carried, on the forward stroke,
past the arm L¹ with the fixed pawl without moving the gear, this pawl being.
hinged or jointed; but on the backward stroke of the tool, carriages or non-cutting
stroke of the machine, the ratchet L' comes in contact with the stationary pawl land.
moves one or more teeth, which motion is communicated through the change.
wheels kk, upright shaft J', worm and worm wheels J J, and spindle I¹; and the
spindle I is advanced according to the extent of motion given to the ratchet L by
the pawl on the arm L' which can be set to suit any pitch of the groove in the
roller being cut. The pitch and number of grooves. in the roller or other surface
can be varied to any required extent by means of the change wheels k k k through
which motion is communicated. The screws C, which work the sliding tool
carriages B may be actuated by any convenient gearing to give a slow forward
motion to the cut and a quick return, as in ordinary planing machines, either by
the use of an open and a cross belt, or as is indicated in the Drawings by a saw-
tooth clutch M, or a friction clutch, fitted on the shaft E by a groove and feather,.
and arranged to engage with corresponding saw teeth or friction surfaces on the
boss of a worm wheel N actuated through speed-reducing gearing N¹, or by means
of a mitre wheel O, directly actuated from the driving shaft P, which may be
driven by a belt and fast and loose pulleys P¹. The reversing action is effected by
a tappet rod Q, connected by a weighted lever Q1 to the clutch M, this rod being
fitted with spring tappets or stops q against which a bracket B' fixed to the

page_text: carriage B presses when the carriage comes to the end of its stroke. I prefer to
throw the tool or tools b out of the cut at the end of the stroke and keep it clear
of the work when running back and throw it in when the machine reverses.
This may be done in various ways, for example, by having a spring at each end
of the machine for each tool holder with chains attached, and so set that the one
pulls the tool out and the other pulls it in; or by having two shifting brackets
fixed to the slide with projecting fingers to act on the tool holder at front and back,
or by connecting a crank or eccentric to the tool to take it out of action at the back
stroke.
To convert the machine into a screw-cutting machine it is only necessary to take
off the quadrant I, and substitute a wheel which requires to be keyed on the
spindle I¹.
One screw C and one slide A¹ may carry two, three, or more tools b on the same
carriage, or on separate carriages, for either fluting or screw-cutting; and a set of
change wheels and swing plate may be used for varying the speed of traverse of
the cutting tools.
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Having now particularly described the nature of my said Invention and in what
manner the same is to be performed, I declare that what I claim is,―
First. The arrangement or combination of parts forming the improved machine
for fluting or grooving cylindrical surfaces, substantially as herein described, and
illustrated in the accompanying Drawings.
Second. In machines of the class described for fluting or grooving cylindrical
surfaces, the combination with the slide bed A of the two screw shafts actuated by
suitable gearing and one or more sliding tool carriages arranged to act on both sides
of the work, substantially as herein described and illustrated by the accompanying
Drawings.
Third. In machines of the class described for fluting or grooving cylindrical
surfaces, the arrangement or combination of the quadrant or wheel I, with the
change wheels g, and worm gearing, operated from the main shaft E, substantially
as and for the purpose herein set forth.
Fourth. In machines of the class described for fluting or grooving cylindrical
surfaces, the arrangement or combination of the ratchet L and adjustable pawl l,
with the change wheels carried by the quadrant or wheel I and actuating the
spindle I through the worm gearing J, J', substantially as and for the purpose
herein set forth..
Fifth. In fluting machines of the class described, the arrangement of gearing
described and illustrated, for effecting a rapid reversing action of the sliding tool.
carriage or carriages.
. In witness whereof, I, the said William Robertson, have hereunto set my hand
and seal this Second day of January, in the year of our Lord, One thousand eight
hundred and eighty-four.