IMPROVEMENTS IN MACHINERY AND TOOLS EMPLOYED IN TURNING."
Year: 1876

page_text: LETTERS PATENT to Andrew Charles Guy Thompson, of Cambridge Road,
Chiswick, in the County of Middlesex, for the Invention of "IMPROVEMENTS
IN MACHINERY AND TOOLS EMPLOYED IN TURNING."
PROVISIONAL SPECIFICATION left by the said Andrew Charles Guy
Thompson at the Office of the Commissioners of Patents on the 20th December
1876.
ANDREW CHARLES GUY THOMPSON, of Cambridge Road, Chiswick, in the
County of Middlesex. "IMPROVEMENTS IN MACHINERY AND TOOLS EMPLOYED
IN TURNING."
My Invention has for its object improvements in machinery and tools employed
in turning, and is more especially applicable to machinery of a like character to that
for which Letters Patent were granted to William Parsons, dated June 21, 1876,
Number 2569, and to other arrangements of machinery of a like character.
My improvements consist, first, in the employment of a hollow bush, which
according to my Invention is mounted with capability of rotating in bearings
carried by the saddle or travelling bed of the lathe. These rotating bushes I cause
to revolve with and at the same velocity as the articles being turned, and when
practicable I prefer to drive the bush itself, and consequently the article inside of it,
whereby I am enabled to dispense with the headstock and employ a second poppet
head in lieu thereof. The hole in this bush or rotating support may be of any
suitable form to suit the form of the article being turned, but the centre thereof
must be coincident with the centre of the article to be turned.
In some cases I cause the bush to be rotated by the rotation of the article therein,
in which cases the articles to be turned are mounted between the headstock and
poppet head as usual.
"
When the pieces of material to be turned do not vary much in form and
dimensions the one from the other, I prefer to employ a solid or inexpansive bush,
the hole or aperture therethrough having a slight taper or draw, that is to say, the
front part is somewhat larger than the back.
When the pieces of material to be turned are not sufficiently similar in form and
size, I use a rotating bush or hollow support, the sides of which are capable of
DC71

page_text: expanding and contracting so as to follow automatically the size and form of the
material to be turned.
When the article to be turned has angular sides I prefer to use grooved rollers to
form the supporting surfaces for the article being turned of the hollow rotating
bush, which grooved rollers may or may not be acted upon by springs, and which
are fitted preferably either on the back or front side, or on both sides of the bush,
round about the hole therein, and I prefer to keep the outer or rolling surface of
the bush as small as possible.
By using a revolving hollow bush or support I am enabled to dispense with the
roughing tool described in the Provisional Specification of the Patent herein-before
referred to, and I am also enabled to turn articles on which it is desired to preserve
one or two square ends.
The saddle which carries the rotary bush, slide rest, and shaping tool is brought
forward by means of the rack and pinion to the point at which it is desired the
patterns should commence. The square or original form, whatever it may be, is thus
preserved at both ends, and can by the same means, when so desired, be also
preserved at any other part of the article.
My improvements also relate to the form of the tools and the angle at which
they are set.
When it is desired to produce patterns containing acute angles or sharp deep
mouldings or curves it is essential that the tool should partake largely of the chisel
form, and although not absolutely necessary I find it beneficial to give clearance at
both the back and front of the cutting end by hollowing out the tool very similar
to a hollow ground razor. I also cause the cutting edge of the tool to act in a
nearly vertical line, and I round off the heel or lower corner, keeping the curved or
rounded part blunt; it is obvious the thinner or longer the cutting edge of the tool
the more intricate and delicate the pattern it is enabled to produce. The tool is set
in the holder (which may be of any suitable construction, or there may be several
tools set in a revolving holder, in which case it takes the form of a flying cutter), at
a cant or angle forward, 'inclining to the pitch of the leading screw, that is to say, if
straight lines were drawn from both the upper and lower edges of the tool, cutting
the leading screw at a right angle, the line produced from the upper edge would be
somewhat in advance of that from the lower.
Although not absolutely necessary I find the best results are obtained from a
tool the lower or rounded heel of which protrudes in advance of the upper.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew Charles Guy Thompson in the Great Seal Patent Office
on the 20th June 1877.
ANDREW CHALES GUY THOMPSON, of Cambridge Road, Chiswick, in the
County of Middlesex. "IMPROVEMENTS IN MACHINERY AND TOOLS EMPLOYED
IN TURNING."
My Invention has for its object improvements in machinery and tools employed
in turning, and is inore espcially applicable to machinery of a like character to that
for which Letters Patent were granted to William Parsons, dated June Twenty-
first, One thousand eight hundred and seventy-six, No. 2569, and to other arrange-
ments of machiney of a like character.
My improvements consist, first, in the employment of a hollow bush, which
according to my Invention is mounted with capability of rotating in bearings
carried by the saddle or travelling bed of the lathe. These rotating bushes I cause
to revolve with and at the same velocity as the article being turned, and when
practicable I prefer to drive the bush itself, and consequently the article inside of it,
whereby I am enabled to dispense with the headstock and employ a second poppet

page_text: head in lieu thereof. The hole in this bush or rotating support may be of any
suitable form to suit the form of the article being turned, but the centre thereof
must be coincident with the centre of the article to be turned.
In some cases I cause the bush to be rotated by the rotation of the article therein,
in which cases the articles to be turned are mounted between the headstock and
poppet head as usual.
When the piecos of material to be turned do not vary much in form and
dimensions the one from the other, I prefer to employ a solid or inexpansive bush,
the hole or aperture therethrough having a slight taper or draw, that is to say, the
front part is somewhat larger than the back.
When the pieces of material to be turned are not sufficiently similar in form and
size, I use a rotating bush or hollow support, the sides of which are capable of
expanding and contracting, so as to follow automatically the size and form of the
material to be turned.
When the article to be turned has angular sides I prefer to use grooved rollers to
form the supporting surfaces for the article being turned of the hollow rotating bush,
which grooved rollers may or may not be acted upon by springs, and which are
fitted preferably either on the back or front side, or on both sides of the bush, round
about the hole therein, and I prefer to keep the outer or rolling surface of the bush
as small as possible.
By using a revolving hollow bush or support I am enabled to dispense with the
roughing tool described in the Provisional Specification of the Patent herein-before
referred to, and I am also enabled to turn articles on which it is desired to preserve
one or two square ends.
The saddle which carries the rotary bush, slide rest, and shaping tool is brought
forward by means of the rack and pinion to the point at which it is desired the
pattern should commence. The square or original form, whatever it may be, is thus
preserved at both ends, and can by the same means, when so desired, be also preserved
at any other part of the articlc.
My improvements also relate to the form of the tools and the angle at which
they are set.
When it is desired to produce patterns containing acute angles or sharp deep
mouldings or curves it is essential that the tool should partake largely of the chisel
form, and although not absolutely necessary I find it beneficial to give clearance at
both the back and front of the cutting end by hollowing out the tool very similar
to a hollow ground razor. I also cause the cutting edge of the tool to act in a
nearly vertical line, and I round off the heel or lower corner, keeping the curved or
rounded part blunt; it is obvious the thinner or longer the cutting edge of the tool
the more intricate and delicate the pattern it is enabled to produce. The tool is set
in the holder (which may be of any suitable construction, or there may be several
tools set in a revolving holder, in which case it takes the form of a flying cutter), at
a cant or angle forward, inclining to the pitch of the leading screw, that is to say, if
straight lines were drawn from both the upper and lower edges of the tool, cutting
the leading screw at a right angle, the line produced from the upper edge would be
somewhat in advance of that from the lower.
Although not absolutely necessary I find the best results are obtained from a
tool, the lower or rounded heel of which protrudes in advance of the upper, as
represented in the accompanying Drawings.
And in order that the said Invention may be clearly understood and readily
carried into effect, I will proceed, aided by the accompanying Drawings, fully to
describe the same.
DESCRIPTION OF THE DRAWINGS.

page_text: Figure 5 is a plan of the slide rest and saddle with the revolving hollow bushes
removed.
Figure 6 is a plan, Figure 7 a sectional plan, Figure 8 a side elevation, and
Figure 9, an edge elevation of portions of the saddle and slide rest with one of the
cutters, and one revolving hollow bush drawn to a larger scale.
Figure 10 is a side view of a hollow revolving bush and its support, separately,
and Figures 11 are respectively a side view, a bottom edge view, and a top edge
view of one of my improved cutters separately.
a is the bed plate of the machine which is supported by suitable standards in the
usual manner. This bed plate is represented in the Drawing as currying two
headstocks b, the mandrils of which are fitted with chucks or face plates b' to
carry the ends of the material to be turned which is kept in its place against the
chucks b by poppet heads c of the usual construction, a set screw be being employed
to prevent endway motion of the material being turned; or a dog chuck may be
employed in licu thereof. If desired, however, only one or more than two head-
stocks and poppet heads may be combined in one machine. To the bed a is fitted
a saddled which is capable of being moved backwards and forwards between the
headstocks b and poppet heads c by means of a leading screw e running from one
end of the machine to the other, and caused to revolve by a strap or band acting on
a pulley e fixed on one end of the screw e or by other suitable means.
In order,
however, to facilitate the speedy back motion of the saddle d, instead of causing
the screw e to act in combination with a complete nut formed or fixed in a pro-
jection from the saddle d, I employ a half nut f, which is connected by a link ƒ¹ to
a lever f, by which it can when desired be raised out of gear with the screw e when
the saddle & can be run quickly back by means of the toothed pinion g and toothed
rack has is well understood. At right angles to the bed a is a rest or support j for
the material to be turned, fixed to, and standing vertically from the face of the
saddle d. In bearings formed in the rest or support are mounted bushes, provided
with holes of different sizes, according to the size of the material to be turned.
These bushes are according to my Invention mounted with capability of rotation in
their bearings, and they are caused to revolve with and at the same velocity as the
article being turned, and when practicable I prefer to drive the bush itself and by
it the article passing through it, whereby I am enabled to dispense with the head-
stock b, and to employ a second poppet head in lieu thereof. I have not thought it
necessary to show this modification, as such will be readily understood by the above
description. The holes in these bushes or rotating supports may be of any suitable
form to suit the form of the article being turned, but the centre thereof must be
coincident with the centre of the article to be turned.
k
In some cases, as shown in the Drawings, I cause the bush or hollow support to
be rotated by the rotation of the article therein, in which cases the articles to be
turned are mounted between the headstock band poppet head c as usual.
When the pieces of material to be turned do not vary much in form and
dimensions, the one from the other, I prefer to employ a solid or inexpansible
bush or hollow support having the hole or aperture therethrough formed with
a slight taper or draw, that is to say, the front part is somewhat larger than
the back.
When the pieces of material to be turned are not sufficiently similar in form and
size, I use a rotating bush or hollow support the sides of which are capable of
expanding and contracting by means of springs acting thereon so as to follow
automatically the size and form of the material to be turned.
When the article to be turned has angular sides I prefer to use grooved rollers
to form the supporting surfaces for the article being turned of the hollow rotating
bush or support, which grooved rollers are mounted in bearings formed in lugs or
projections carried by the hollow rotating bush, and these grooved rollers ¹
may be acted upon by india-rubbor springs or tubes interposed between the axes
thereof and their bearings. These grooved rollers are fitted preferably for con-
venience of manufacture, either on the back or front side, or on both sides of the

page_text: bush, round about the hole therein, and I prefer to keep the outer or rolling surface
of the bush as small as possible.
By using a revolving hollow bush or support for the material to be turned, I am
enabled to dispense with roughing tools required for cutting the material to the size
of the holes in the bushes when stationary or non-rotating bushes or supports are
employed, and I am also enabled to turn articles on which it is desired to preserve
one or two square ends, whilst any portion intermediate of the ends may also be
left square or unturned, as may be required. The material to be turned passes
through the bushes to the pattern cutting knives or tools, which are fixed in
tool holders m, carried by a slide n at right angles to the bed a, which is capable of
sliding backwards and forwards on guides o, bolted to the saddle d. The slide
rest n has elongated holes n' formed therein, as shewn at Figure 5, to enable the
rest or support to be fixed rigidly to the saddle d, and yet permit the free motion
of the slide rest n on its guides o. A template p of the pattern or design to be cut
on the wood or other material is held on the brackets 7 bolted to the side of the
bed a.
The edge of the template 2 is shaped to the pattern desired to be cut.
A finger or projection n from the slide rest is held up to, and caused to follow
the pattern on the template p by a spring ?, or it may be by a weight or other
suitable means, which, combined with the action of the leading screw e, causes the
cutting or shaping tools to follow the pattern on the template p, and thereby
causes the wood or other material being turned to be cut to the pattern on the
template p; a cam f³ fixed to the lever facts upon a projection n³ from the slide
rest n when the lever fis depressed, so that when the nut fis removed from the
screw e the slide rest is at the same time drawn back, so as to remove the shaping
cutters from contact with the wood or other material being turned.
By increasing the number of poppet heads, headstocks, tool holders, with cutting
tools and hollow rotating bushes or supports for the wood, the machinery or
apparatus may be arranged to turn more than two articles simultaneously of tho
same pattern.
My Invention also relates to the form of the cutting tools and the angle at which
they are set.
When it is desired to produce patterns containing acute angles or sharp deep
mouldings or curves, it is essential that the cutting tool should partake largely of
the chisel form, as represented at Figures 11, and although not absolutely necessary
I find it beneficial to give clearance at both the back and front of the cutting end
by hollowing out the tool at very similar to a hollow ground razor. I also cause
the cutting edge of the tool to act in a nearly vertical line, and I round off the
heel or lower corner 13, keeping the curved or rounded part blunt in order to enable
it to act as a smoothing surface and polisher; it is obvious the thinner or longer the
cutting edge of the tool, the more intricate and delicate the pattern it is enabled to
produce. The tools are set in the holders m with their cutting edges at a cant or
angle forward inclining to the pitch of the leading screw e, that is to say, if straight
lines were drawn from both the upper and lower edges or corners 14, 1, of the tool l,
cutting the leading screw at a right angle, the line produced from the upper edge li
would be somewhat in advance of that from the lower edge ³.
Although not absolutely necessary, it is found that the best results are obtained
from a tool, the lower or rounded heel 3 of which protrudes in advance of the upper
edge, as represented in the accompanying Drawings.
I would here remark that these improved cutters may if desired be mounted in
rotating tool holders, and be used as flying or rotating cutters, as will be readily
understood.
Having thus described the nature of my said Invention and the mode in which
I carry the same into effect, I would have it understood that what I claim is,―
First. The employment of rotating hollow bushes or supports k for the material
to be turned and rotating at the same speed therewith, whereby I am enabled to
dispense with the roughing cutters heretofore required when employing fixed or

page_text: non-rotating bushes or supports to cut down the material to the bore of such fixed
or non-rotating bushes or supports.
Secondly, I claim giving rotary motion to the material being turned by means of
rotating hollow bushes or supports, whereby I am enabled to dispense with a head-
stock, and to mount the material to be turned between two poppet heads,
substantially as herein described.
And, Thirdly. I claim the employment of cutting tools 1, constructed, mounted,
and operating in manner substantially as herein shown and described.
In witness whereof, I, the said Andrew Charles Guy Thompson, have here-
unto set my hand and seal, this Nineteenth day of June, in the year of our
Lord. One thousand eight hundred and seventy-seven.