Improvements applicable to Machines for Cutting Elliptical and other Eccentric Forms.
Year: 1898

page_text: Date of Application, 23rd June, 1898
Complete Specification Left, 22nd Mar., 1899-Accepted, 13th May,
1899
PROVISIONAL DIE
Improvements applicable to Machines for Cutting Elliptical and
other Eccentric Forms.
We, JOHN BARR, of 39, Dundonald Road, Kilmarnock, in the County of Ayr,
North Britain, Engineer, and ROBERT THOMSON, of 45, Dundonald Road, afore-
said, Engineer, do hereby declare the nature of this invention to be as follows, that
is to say:-
Our said invention relates to machines used for cutting elliptical forms, such
as those of manholes and manhole doors, or the like in metal plates; and it
has for its object by simple and convenient devices to adapt such machines for
cutting eccentric or non-circular forms differing more or less from ellipses, and
more suitable for some applications.
In a machine to which our improved devices are applicable the plate to be cut
is fixed upon a saddle or chuck plate which is fitted to and receives motion from
a circular plate or frame having fixed to or in one piece with it a worm-toothed
ring gearing with a worm on a power-driven shaft. The cutting tool is carried
by a holder which is adjustable towards or from the chuck plate, and also in a
direction parallel thereto. Within the rotating frame carrying the chuck plate
there is a stationary pin which is adjusted eccentrically to suit the proportion of
ellipse required in each case, and which has loose on it a block engaging in a
Ordinarily the eccentric pin is
groove on the inner side of the chuck plate.
adjusted only at the commencement of each cutting operation, the resulting forin
being an ellipse. By our invention the eccentric pin has applied to it mechanism
which moves it during a cutting operation, the movement being derived from a
rotating crank, eccentric, or cam, the form thereby obtained differing more or
less as desired from that of a simple ellipse. In a similar way we apply to the
cutting tool mechanism which moves it during a cutting operation, the movement
This movement of the
being derived from a rotating crank, eccentric or cam.
tool holder may in some cases be employed instead of the movement of the
eccentric pin and in some cases movements of the eccentric pin and of the tool
holder may be combined.
1
& Tune 1808
EDMUND HUNT,
Applicants' Agent.
Improvements applicable to Machines for Cutting Eliptical and
other Eccentric Forms.
We, JOHN BARR, of 39, Dundonald Road, Kilmarnock, in the County of Ayr,
North Britain, Engineer, and ROBERT THOMSON, of 45, Dundonald Road, afore-
11

page_text: said, Engineer, do hereby declare the nature of this invention and in what manne
the same is to be performed, to be particularly described and ascertained in and
by the following statement, that is to say;-
-
Our said invention relates to machines used for cutting elliptical forms, such
as those of manholes and manhole doors, or the like in metal plates; and it
has for its object by simple and convenient devices to adapt such machines for
cutting eccentric or non-circular forms differing more or less from ellipses, and
more suitable for some applications.
And in order that our said invention and the manner of performing the same
may be properly understood we hereunto append two sheets of explanatory drawings
to be hereinafter referred to in describing our improvements.
In the accompanying drawings Figures, 1, 2, and 3, are respectively a plan,
a side elevation and an end elevation of a machine provided with our improve-
ments. Figure, 4, is a plan, and Figure, 5, is a transverse vertical section on
an enlarged scale of details in connection therewith. In these drawings the same
reference letters and numerals are used to mark the same or like parts wherever they
are repeated.
In a machine to which our improved devices are applicable the plate, A, to be
cut (shown in dotted lines) is fixed upon a saddle or chuck plate, B. The chuck
plate is fixed by screw bolts, B 1, to a grooved block, B2, of cruciform shape
which works in a slotted part, B3, of a circular plate or frame, C, and thereby
transmits motion from the circular plate to the chuck plate. The circular plate, C,
is fitted to rotate in a V-shaped circular guide, J, on a bed frame, J 1, and it has
fixed or formed on it a wormi-toothed ring, C1, which gears with a worm, D), on
a power driven shaft, D) 1. The cutting tool, E, is carried by a holder, E1,
working in guide brackets, E2, on a saddle, E3, fitted to slide on a cross
frame, E4, arranged to work on vertical guides E5, formed on the framing.
The cutting tool, E, can be moved either towards or from the chuck plate by
means of the spindles, F, and G, and also in a direction parallel to the chuck plate
by means of the spindle, F 1, a power driven vertical shaft, F2, being arranged to
work the hand actuated spindles, F, F1, when desired through worm and spur
gearing, F3, as in similar classes of machines hitherto constructed. Within the
rotating frame, C, carrying the chuck plate, B, there is fitted a stationary pin, H,
which engages in the lower part of the block, B2, and is adjusted eccentrically
to suit the proportion of ellipse required in each case. As ordinarily arranged
the eccentric pin, H, engaging in the block, B2, is adjusted only at the commence-
ment of each cutting operation, while the machine is stopped, the resulting form
being an ellipse. By our invention the eccentric pin, H, has also applied to it
mechanism to be hereinafter described which moves it during a cutting operation.
The eccentric pin, H, is according to our invention fixed to a block, K, fitted to
slide in guides, K1, formed on the frame, J1, and is adjusted by a screwed
spindle, L, which works in the block and has its outer end carried by a bracket, L 1,
fixed to the bed frame, J 1, a pointer, L2, and scale, L3, being provided to indicate
the position of the eccentric pin at any time during a cutting operation. The
eccentric pin, H, can be fixed in any desired position by means of a pinching
screw, K2, which is arranged to act against the side of the block, K. A rod, M,
attached to the block, K, passes through a guide gland, M1, and receives motion
through a connecting rod, M2, fixed to it and to a crank pin, M 3, on a disk, M4,
fixed to a shaft, M5, mounted on a bracket, M6, the disk being rotated through
a worm-wheel, N, gearing with a worm, N 1, on a shaft, N 2, driven from the
main shaft, 11, through pinions, N3, N4. When it is desired to move the
ercentric pin, H, during a cutting operation, and thereby form an irregular
figure other than a true ellipse, the adjusting spindle, L, is disconnected from the
block, K and the rod, M, being connected to the block, and rotating disk, M4,
thereby gives movement to the eccentric pin and forms the type of figure desired.
When it is desired to move the eccentric pin, H, by hand only, during a cutting
operation, the adjusting spindle, L, is connected to the block, K, and the rod, M,

page_text: is disconnected from the rotating disk, M4. The eccentricity of the crank,
pin, M3, can be varied, and the sticke of the rod, M, thereby altered by means of
a screwed spindle, MT, which is fitted in the disk, M4, so as to engage with the
crank pin and shift it either towards or from the centre of the disk. Instead of
employing a rotating cranked disk, M 4, to give motion to the block, K, an eccen-
tric, or cam, may be employed if desired. In a similar way we apply to the cutting
tool, 1, mechanism which moves it during a cutting operation. The movement
is derived from a cam, P, formed on a shaft, P1, mounted on brackets P2, P3,
on the cross frame, E4. An upper shaft, Q, mounted on the framing is driven
by belt gearing from the main shaft, D1, and through a worm, Q1, and a worm-
wheel, Q2, drives a vertical shaft, Q3, which likewise through a worm, Q4,
acting on a worm wheel, Q, on the cam shaft, P1, thereby drives the cam, P.
The cam, P, engages between two antifriction rollers, R, fitted on a tappet R 1,
fixed to a tappet rod, R2, the rod being guided in the bracket, P3, and fixed in
lugs, E6, on the saddle, E3, by pinching screws, R3, so that the tappet rod can
be easily disconnected when desired. The cam, P, in rotating thereby moves the
tappet, R1, rod R2, and saddle, E3, and thus gives the desired movement to
the cutting tool, E, during a cutting operation, similar to that described with
reference to the eccentric pin, H. The bracket, P3, by means of the slot, P4,
can be adjusted inwards or outward. so as to suit different sizes of cams. Instead
of employing a cam, 1', for giving movement to the cutting tool, E, a rotating
crank, or eccentric, may be employed if desired. This movement of the cutting
tool, E, may in some cases be employed instead of the movement of the eccentric
pin, I, as herein before described, and in some cases movements of the eccentric
pin, H, and of the cutting tool, E, may be combined.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. In machines for cutting elliptical and other eccentric forms, making the
eccentric pin capable of being moved by hand during a cutting operation, by
fixing it to a block sliding in guides within the rotating frame carrying the
chuck plate, the block being moved by a hand actuated screwed spindle, engaging
in it, and provided with an indicator for indicating the position of the eccentric
pin or capable of being moved automatically, by a rod which is fixed to the
eccentric pin sliding block, and is connected to a rotating crank eccentric, or
cam, driven through gearing from the main shaft of the machine substantially
as and for the purposes hereinbefore described.
:
2. In machines for cutting elliptical and other eccentric forms, moving the
cutting tool during a cutting operation by a cam, eccentric, or crank, driven
through gearing from the main shaft of the machine and acting through a rod
or equivalent on the saddle carrying the tool holder, substantially as and for the
purposes hereinbefore described.
Dated this Twenty-first day of March 1899.
EDMUND HUNT,
Applicants' Agent.