IMPROVED MACHINERY FOR CUTTING AND SHAPING METALS
Year: 1885

page_text: I GEORGE GREENWOOD of Albion Works, Leeds in the County of York,
Engineer do hereby declare the nature of the invention for IMPROVED MACHINERY
FOR CUTTING AND SHAPING METALS and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to a novel construction of machine suitable for a great
variety of work. It is specially applicable for cutting milling tools of an irregular
form, and that, whether their teeth run in straight lines or helically, also for
cutting twist drills, toothed wheels, and reamers, and for grooving screw taps.
A peculiar feature of the improved machine is, that the cutter spindle headstock
is capable of being swivelled on axes which cross each other at right angles and of
being locked in any desired position.
Another feature of novelty, is the use of a former, which is made capable of being
traversed at a superior speed to that of the work, for the purpose of minimising
any inequalities in the working of the milling tool, while reproducing irregular
forms.
Besides these peculiarities, the machine has the merit of compactness in its
construction, is capable of accurate adjustment for working, and provides for the
advance of the work to the cutter in a vertical, a transverse, and a longitudinal
direction, as well as of its moving axially under the cutter.
In the accompanying drawings:
Fig: 1 is a front elevation of the machine, and
Fig 2 is a side elevation of the same.
Fig: 3 is a partial elevation on an enlarged scale of the opposite side of the
machine to that shown at Fig: 2.
In these Figures A is a hollow standard of cast iron which serves to support the
various working parts of the machine.
B is a transverse driving shaft having its bearings in the hollow standard, and
fitted with fast and loose band pulleys b. 6¹ is a mitre wheel keyed to the driving
shaft and gearing into a mitre wheel c on a horizontal shaft C mounted at right
angles to the driving shaft and having its bearings in the standard A and in a
[Prine 8

page_text: bracket arm A' cast with the standard. Keyed to this shaft C is a group of four-
speed driving pulleys c¹ which through a band serve to transmit rotary motion to
a longitudinal shaft D through a second group of four-speed driving pulleys d
keyed to that shaft.
On the top of the standard is fitted a slide D¹ which is capable of receiving a
transverse sliding motion. Upon this slide D¹ is mounted a slide D² which is
capable of receiving a longitudinal motion or a movement in the line of the
shaft D. This shaft D is mounted upon the slide D' and it is supported at its
opposite ends by bearings, the one carried by the bracket arm D¹* cast with the
slide D¹ and the other by an arm E pivotted on the slide D³. This arm which is
made with a forked extremity is capable of being shifted axially around the shaft D
and locked in its adjusted position on the slide D²
The pulleys d are keyed to a sleeve d' which turns freely in the bearing of the
bracket arm D¹* and receives the rear end of the shaft D to which it is connected
by a feather This arrangement permits of the shaft sliding endwise without
disturbing the position of the pulleys & with respect to the pulleys c¹ when the
slide D³ is shifted. The object of this movement of the shaft D is to enlarge the
range of action of the milling tool.
Mounted in the forked end of the arm E is the headstock E' which turns on
trunnions or pivots foring a divided axle The axis of these trunnions cuts at
right angles the axis of the arm. In this headstock is carried the spindle E' of the
milling tool e the axis of which cuts the point of intersection of the axes of the
forked arm E and the trunnions of the headstock. Rotary motion is imparted to
the spindle and tool which it carries by bevil gearing 1, 2, 3 the bevil wheel 2
being interposed between the pinions 1 and 3 and mounted loosely on one of the
trunnions of the headstock for the purpose of transmitting motion from the
pinion 1 on the shaft D to the pinion 3 on the spindle E³ whatever position that
spindle may take (through the swivelling of the headstock) with respect to a
vertical plane at right angles to the side of the machine.
For
The work is presented to the milling tool by a pair of adjustable headstocks F
suitably fitted to allow of the work being turned on its axis and either inter-
mittently or continuously according to the work in hand. This pair of headstocks
is mounted on a table F¹ which is free to receive a traverse motion transversely
of the machine and thereby move the longitudinally under the cutter e
giving the work a traverse motion at right angles to this movement the table,
is mounted on a slide F2 and this again on a slide F3 which is itself carried by a
vertically sliding bracket support F4 working in vertical slides in the front face of
the standard A. A tendency is given to the slide F³ to move inwards by means of
an adjustably weighted lever f which movement is controlled by means of a former
or pattern piece G mounted on the inner side of the table F¹ and bearing against a
stationary bowle g carried by the standard. Mounted on the slide F³ is a
traversing screw f1 which passes through a tapped lug carried by the slide F³ and
is furnished with a hand wheel for turning it. By this means a traverse motion
longitudinal of the machine and at right angles to the main driving shaft may be
imparted to the slide F2 for the purpose of moving the work under the cutter e as
desired. Similarly the table F1 is provided with a traversing screw ƒ* mounted
at right angles to the screw f¹ for the purpose of taking into a tapped lug secured
to the slide F and imparting to the table its traverse motion. This screw is also
provided with a handwheel for working it.
The supporting bracket F4 receives a vertical motion from a screw F³ the upper
end of which is fitted loosely to the bracket while its lower end enters a threaded
socket Fe secured to the standard A. The screw is turned by means of a loose
lever f³ passing through a transverse hole in an enlargement formed on the screw
and according to the direction in which it is turned, it will raise the bracket F' and
thereby carry the work up to the tool or lower it clear of the tool.
Before describing the action of the machine it will be well to explain the mode
of securing the parts above referred to in their adjusted positions. I have said that

page_text: the swivel arm E turns on the shaft D and that it is carried by the slide D³. For
this purpose the slide is flanged to form an abutting face for the arm. An under-
cut annular groove T shaped in cross section is turned in the base of the arm to
receive locking bolts which enter the groove from an opening at the back.
Coincident with this annular groove are bolt holes two or more to receive the
screwed ends of the locking bolts and to the projecting ends of these bolts nuts are
applied at the back of the pierced flange. By slackening these nuts the arm is
free to be turned on its axis to give the requisite inclination in one direction to the
cutter spindle. This adjustment having been effected by hand the arm is locked
in position by the tightening nuts.
For the purpose of securing the headstock in its adjusted position on the arm E
a similar provision for the employment of screw bolts is made. Thus the sides of
the headstock E¹ are formed with countersunk annular grooves T shaped in cross
section with entrances for the screw bolts to the grooves from behind, there being
coinciding bolt holes made in the forked ends of the arm for the bolts to project
through to receive the binding nuts.
Supposing now it is intended to make parallel tangential cuts in a piece of work
carried by the pair of headstocks F, the work is placed in the bite of these head-
stocks which are made in any well known or approved manner and the cutter
spindle is adjusted to the requisite inclination for making the tangential cut, and
secured in position by the binding nuts. The work is then brought up within
reach of the tool and is traversed under it by means of the traversing screw f' while
at the same time rotary motion is imparted to the cutter spindle through the
gearing 1, 2, 3 actuated by the shaft D.
If now it is desired to made a cut parallel to that just made and at a given
distance from it the work is adjusted axially in the headstock F by means of a
dividing plate in the usual way. In this manner tangential cuts equidistant from
each other may be made all around a cylindrical piece of work.
By adjusting the forked arm E so as to tip the cutter spindle in a plane at right
angles to the plane in which it is tipped on the trunnions of its headstock the same
cutter will be enabled to make a segment shaped cut in cross section. Again if
this cut is made while the work is traversed under the combined action of the
travelling table and the slowly rotating centre of the headstock F a helical groove
will be formed around a cylindrical piece of work, the section of the groove being
dependent on the position of the cutter with respect to the work. For giving an
automatic axial motion to the work to obtain the helical cut the arrangement of
change gear shown in Fig 2 is employed, the rotation of the gearing being derived
from the working by hand of the traversing screw f" which imparts the longi-
tudinal motion to the work.
This compound movement of the work is required when cutting twist drills.
For the production of milling tools that are to be used for cutting mouldings, a
former such as those shown at Figs 4 and 5 will be employed. In Fig 3 a
former is shown at G as carried by a slide G which is itself supported by and
capable of traversing over the inner side of the table F¹. To ensure the greatest
accuracy in the cutting of pattern milling tools I give the former an independent
traverse motion causing it to travel some three four or more times faster than the
work which it is designed to control The former I have said is borne up against.
a stationary bowle g by a weighted lever fin order that it may control the lateral
advance of the work towards the rotating cutter while the other movements of the
work already described are proceeding The independent traverse of the former
is effected through an arrangement of change gear g¹ which receives its motion
from the traversing screw f³ mounted on the table F¹. This gearing imparts
rotary motion to a traversing screw g² mounted on the inner side of the table
and working in a tapped lug carried by the slide G₁ on which the former is
secured.
At Figs: 4 I have shown a former such as that which employed in the production
of the milling tool Fig 4*. On comparing these figures it will be seen that the

page_text: pattern of the former is four times the length of the tool. This allows for the
traverse of the former at four times the speed of the work. In like manner at
Fig: 5 I have shewn a former suitable for use in the production of a cutter like
that shown at Fig 5* Both the tools figs 4* and 5* are intended for cutting
mouldings or other work of irregular form and they and their formers are
represented in full size.
As the former is raised and lowered with the table to adjust the height of the
work to the cutter the bowle g is also made adjustable vertically to correspond to
the rise and fall of the former. The bowle g has also an adjustment to and from
the standard A. It is to provide for these adjustments of the bowle that it
is carried in a fork g³ projecting from a slide g capable of sliding vertically on the
face of the standard A. Turning freely on the stem of the fork is a threaded
socket g screwed into the slide g and the end of the fork stem passes through and
is made fast to a squared guide piece which enters a squared hole in the slide
By turning this socket the forked stem may be drawn back from or advanced
towards the former. The slide g' is fitted with clamping screws which secure it in
its adjusted position to the standard A.
I will now describe the means for holding the former up to the bowle and yet
allowing of the former travelling over the bowle as the work is advanced under the
rotating cutter.
Fitted to the underside of the slide F³ immediately below the screw fl is a
rack into which gears a pinion ƒ³ keyed to a transverse shaft ƒª which is carried
in bearings on the slide F. This pinion f" gears into a spur wheel f" on a
transverse shaft f8 also carried by the slide F. Upon a third transverse shaft ƒ³
geared with the second transverse shaft f by a spur wheel f10 and pinion fis
keyed a pulley f¹ to which is fitted adjustably a counterbalancing weighted strap
or chain f¹s Fulcrummed on the second transverse shaft ƒ8 is the hand lever f
which by means of a loose pin is locked to the spur wheel f10 there being a series
of holes in the spur wheel to allow of the application of the locking pin to the spur
wheel in various positions of that spur wheel.
It will now be understood that the tendency of the weighted lever f over-
balancing the weighted strap f13 is to hold the former G in contact with its
bowle g When however the workman desires to draw back the work from the
cutter for the purpose of inspecting the progress of the work or for other reasons
he has merely to lift the hand lever f when through the gearing just described he
will rack back the slide F3 and withdraw the work from the cutter.
For determining with great accuracy the limit of traverse of the work under the
cutter both in the direction of its length and of its width adjustable stops h are
provided the construction of which is best shown at Fig 6. For limiting the
traverse of the table F¹ the slide. F is provided with stops for controlling it and
similarly the slide F³ is provided with stops for limiting the movement of the
slide F and consequently the lateral movement of the table. Referring to Figs 1
and 2 these stops will be seen in position and between each pair is a lug projecting
from the part whose motion it is desired to arrest. h Fig 6 is a stop which is free
to slide in guides formed in the slide which carries the stop. A clamping screw
also fitted to the same guide serves to hold the stop in its roughly adjusted
.position. This stop is made hollow and tapped to receive a screw h³ which near its
milled head is furnished with division lines on its periphery to indicate the
amount of axial motion given to the screw the stop being furnished with an index
line near the graduations to assist in the adjustment of the screw h¹. The opposite
end of the stop is slit and pierced and lugs are formed on either side of the slit to
receive a screw which when tightened up will bind the slit portion upon the
adjusting screw.
For adjusting the cutter spindle to the proper inclination whether in a plane
parallel to the axis of the work or in a plane at right angles thereto, suitable
provision is made for securing the same with facility and accuracy. Thus the base
of the swivel arm E is graduated on its periphery and the cutter spindle headstock

page_text: is also graduated on its periphery there being index lines on the stationary parts
adjacent thereto for guiding the attendant in his adjustment.
The vertical screw F5 which raises and lowers the table F1 with its headstocks is
furnished with division lines for facilitating the accurate vertical adjustment of the
work and a pointer extending down from the slide F* in close proximity to the
graduations serves to indicate the amount of axial motion imparted to the screw
after the rough adjustment.has been obtained.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is
1. The general arrangement of machinery above described for cutting and
shaping metals whereby in addition to the work receiving an accurately limited
traverse motion in two directions at right angles to each other, a vertical motion
and an axial motion, the rotating cutter spindle is made capable of accurate
adjustment in vertical planes at right angles to each other and is capable also of
being shifted in the line of the axis of its driving shaft and at right angles thereto
as and for the purpose above set forth.
2. Mounting the cutter spindle in a headstock that is capable of swivelling in
planes at right angles to each other for the purpose of presenting the rotary cutter
at various inclinations to the work.
3. The application to the table of milling machines of a former having a speed of
traverse greater than that of the work carried by the table for the purpose above
set forth.