Improvements in Boring Machines.
Year: 1892

page_text: Date of Application, 19th Mar., 1892
Complete Specification Left, 19th Dec., 1892-Accepted, 11th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in Boring Machines.
We, EDWIN BRYAN DONKIN, of Southwark Park Road, Bermondsey, in the
County of Surrey, Engineer, and FRANCIS HARMER BACON of 37 Somerville
Road, Queen's Road, S.E. Mechanical Engineer, do hereby declare the nature of
this invention to be as follows :-
This invention has reference to a construction of boring machine designed to
enable the casings of gas exhausters, rotary blowers, and other articles to which it
is desired to impart an oval or other non-circular curved form internally, to be
accurately bored to the desired form in a convenient and economical manner.
For this purpose each end of the boring bar is journalled in a bearing arranged
to slide transversely in a guide-way formed in a standard or support, and to it are
fixed two peculiarly shaped cams each adapted to work against a roller carried by
the standard or support, the arrangement being such that as the boring bar is
rotated, its axis will be caused by the action of the cams against the rollers to
reciprocate transversely to such an extent that the point of a boring tool carried
by such bar will be caused to travel in an oval or other curved path and impart a
corresponding oval or curved form to the interior of the casing or other article
in which it is arranged to work.
In order that the rollers may be kept in close contact with their respective cams,
one of each pair may be made adjustable in the direction of the cam against which
it is to work.
The boring bar can be rotated by a worm wheel driven by a worm on a driving
shaft mounted in one of the standards or supports which may be made adjustable
in the direction of the axis of the boring bar by means of a toothed wheel arranged
to gear with a fixed rack and driven by suitable means such as worm gearing.
Dend this 10th dow of March 1899.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Boring Machines.
We, EDWIN BRYan Donkin, of Southwark Park Road, Bermondsey, in the
County of Surrey, Engineer, and FRANCIS HARMER BACON of 37 Somerville
Road, Queen's Road, S.E. Mechanical Engineer, do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention has reference to a construction of boring machine designed to
enable the casings of gas exhausters, rotary blowers, and other articles to which it
is desired to impart an oval or other non-circular curved form internally, to be
accurately bored to the desired form in a convenient and economical manner.
For this purpose each end of the boring bar is journalled in a bearing arranged
to slide transversely in a guide-way formed in a standard or support, and to it are
fixed two peculiarly shaped cams each adapted to work against a roller carried by
the standard or support, the arrangement being such that as the boring bar is
rotated, its axis will be caused by the action of the cams against the rollers to
reciprocate transversely to such an extent that the point of a boring tool carried
by such bar will be caused to travel in an oval or other curved path and impart a

page_text: ww
which it is arranged to work.
In order that the. rollers may be kept in close contact with their respective
cams, one of each pair may be made adjustable in the direction of the cam against
which it is to work.
The boring bar can be rotated by a worm wheel driven by a worm on a driving
shaft mounted in one of the standards or supports the other of which may be
made adjustable in the direction of the axis of the boring bar by means of a
toothed wheel arranged to gear with a fixed rack and driven by suitable means
such as worm gearing.
In the accompanying illustrative drawings,
Fig. 1 is a side elevation; and
Fig. 2 is an end elevation of a boring machine constructed according to this
invention.
Fig. 3 is a front elevation; and
Fig. 4 is a plan of one of the standards or supports.
Fig. 5 is a side elevation showing the mode of mounting and adjusting one of
the rollers against which the cams fixed on the boring bar work.
Figs. 6 and 7 are sections on the lines a b and c d respectively of Fig. 5.
Figs. 8 and 9 are respectively side and end elevations of one of the fixed rollers,
and the bracket in which it is mounted.
Fig. 10 is a diagrammatic view to a larger scale.
A is a boring bar carrying a boring tool B and journalled at the ends in
bearings C each arranged to slide transversely in a guide way D formed in the
corresponding standards. E E. To each end of the boring bar are fixed two
cams F, F¹ arranged to work between and against two rollers G G¹ mounted to
Fotate about pins H H' carried by brackets I I¹ respectively fixed to the outer end
the corresponding standard.
For boring a blower casing or other article to an oval or elliptical form as
shown in Fig. 10, the cams F and F at each end of the boring bar A are made of
the peculiar form shown in that figure and are arranged so that one of them vis. F
works against the roller G and moves the shaft laterally in one direction, and then
the other viz. F works against the roller G and moves the shaft laterally in the
opposite direction with the result that the bar whilst being rotated is simultaneously
reciprocated laterally in a horizontal plane and the point B¹ of the boring tool
carried by such bar will be caused to travel in an oval path represented by the
line P. By varying the form of the cams, the form of the path can be corre
spondingly varied. The pin H upon which the roller -G is directly mounted, is
fixed in place it may be by a pin H (Figs. 8 and 9). The pin H' for the roller G
is of square or rectangular form in cross section and is fitted with a sleeve K
through which the pin H can slide and around which the roller G¹ can turn
(Figs. 56 and 7). The said pin H' is arranged to slide in a corresponding
recess L formed in the bracket L', the pin and the surfaces M M' against which
it bears being made inclined or tapered as shown so that when the pin is moved
endways in an inward direction by the aid of nuts N N¹ working on the screw
threaded portion I* of the pin, which passes through a plain hole in a fixed stirrup
piece O, the axis of the pin about which the roller G₁ turns will be moved nearer
to the axis of the boring bar for the purpose herein before mentioned. The boring
bar is rotated by a worm wheel Q driven by a worm R on a driving shaft S
mounted in bearings at the base of the standard E. The standard E is made
adjustable in the direction of the axis of the boring bar A to admit of work being
placed in position for the boring tool to act thereon, and to be afterward removed.
For this purpose the said standard has mounted in the base thereof a toothed
wheel T that gears with a rack U fixed to the bed plate V of the machine and is
driven by a hand wheel W shaft X worm Y and worm wheel Z. E' is a
supplementary standard for the boring bar. It is provided with a sliding bearing
like the others,

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that
what we claim is :-
1. A boring machine wherein the boring bar is journalled in bearings arranged
to slide transversely in suitable guide-ways and has fixed to each of its ends two
cams each adapted to work against a roller turning about a fixed axis, the arrange-
ment being such that when the boring bar is rotated its axis will be caused by the
action of the cams against the rollers to reciprocate transversely and cause the
outting point of a boring tool carried by such bar to travel in an oval or other
curved path depending upon the form of the cams substantially as herein described
for the purpose specified.
2. The improved boring machine constructed substantially as described and
shown.
LS LL 1
n1000
EDWIN BRYAN DONKIN.
W. Lloyd Wise,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.Č., Agent for the Applicants.